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Sample records for optimization significantly improves

  1. Codon Optimization Significantly Improves the Expression Level of α-Amylase Gene from Bacillus licheniformis in Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Jian-Rong Wang

    2015-01-01

    Full Text Available α-Amylase as an important industrial enzyme has been widely used in starch processing, detergent, and paper industries. To improve expression efficiency of recombinant α-amylase from Bacillus licheniformis (B. licheniformis, the α-amylase gene from B. licheniformis was optimized according to the codon usage of Pichia pastoris (P. pastoris and expressed in P. pastoris. Totally, the codons encoding 305 amino acids were optimized in which a total of 328 nucleotides were changed and the G+C content was increased from 47.6 to 49.2%. The recombinants were cultured in 96-deep-well microplates and screened by a new plate assay method. Compared with the wild-type gene, the optimized gene is expressed at a significantly higher level in P. pastoris after methanol induction for 168 h in 5- and 50-L bioreactor with the maximum activity of 8100 and 11000 U/mL, which was 2.31- and 2.62-fold higher than that by wild-type gene. The improved expression level makes the enzyme a good candidate for α-amylase production in industrial use.

  2. Significant improvements in InGaN/GaN nano-photoelectrodes for hydrogen generation by structure and polarization optimization.

    Science.gov (United States)

    Tao, Tao; Zhi, Ting; Liu, Bin; Li, Mingxue; Zhuang, Zhe; Dai, Jiangping; Li, Yi; Jiang, Fulong; Luo, Wenjun; Xie, Zili; Chen, Dunjun; Chen, Peng; Li, Zhaosheng; Zou, Zhigang; Zhang, Rong; Zheng, Youdou

    2016-02-08

    The photoelectrodes based on III-nitride semiconductors with high energy conversion efficiency especially for those self-driven ones are greatly desirable for hydrogen generation. In this study, highly ordered InGaN/GaN multiple-quantum-well nanorod-based photoelectrodes have been fabricated by a soft UV-curing nano-imprint lithography and a top-down etching technique, which improve the incident photon conversion efficiency (IPCE) from 16% (planar structure) to 42% (@ wavelength = 400 nm). More significantly, the turn-on voltage is reduced low to -0.6 V, which indicates the possibility of achieving self-driven. Furthermore, SiO2/Si3N4 dielectric distributed Bragg reflectors are employed to further improve the IPCE up to 60%. And the photocurrent (@ 1.1 V) is enhanced from 0.37 mA/cm(2) (original planar structure) to 1.5 mA/cm(2). These improvements may accelerate the possible applications for hydrogen generation with high energy-efficiency.

  3. Optimization of Deep Drilling Performance--Development and Benchmark Testing of Advanced Diamond Product Drill Bits & HP/HT Fluids to Significantly Improve Rates of Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Alan Black; Arnis Judzis

    2003-10-01

    This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2002 through September 2002. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit--fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. Accomplishments to date include the following: 4Q 2002--Project started; Industry Team was assembled; Kick-off meeting was held at DOE Morgantown; 1Q 2003--Engineering meeting was held at Hughes Christensen, The Woodlands Texas to prepare preliminary plans for development and testing and review equipment needs; Operators started sending information regarding their needs for deep drilling challenges and priorities for large-scale testing experimental matrix; Aramco joined the Industry Team as DEA 148 objectives paralleled the DOE project; 2Q 2003--Engineering and planning for high pressure drilling at TerraTek commenced; 3Q 2003--Continuation of engineering and design work for high pressure drilling at TerraTek; Baker Hughes INTEQ drilling Fluids and Hughes Christensen commence planning for Phase 1 testing--recommendations for bits and fluids.

  4. (Too) optimistic about optimism: the belief that optimism improves performance.

    Science.gov (United States)

    Tenney, Elizabeth R; Logg, Jennifer M; Moore, Don A

    2015-03-01

    A series of experiments investigated why people value optimism and whether they are right to do so. In Experiments 1A and 1B, participants prescribed more optimism for someone implementing decisions than for someone deliberating, indicating that people prescribe optimism selectively, when it can affect performance. Furthermore, participants believed optimism improved outcomes when a person's actions had considerable, rather than little, influence over the outcome (Experiment 2). Experiments 3 and 4 tested the accuracy of this belief; optimism improved persistence, but it did not improve performance as much as participants expected. Experiments 5A and 5B found that participants overestimated the relationship between optimism and performance even when their focus was not on optimism exclusively. In summary, people prescribe optimism when they believe it has the opportunity to improve the chance of success-unfortunately, people may be overly optimistic about just how much optimism can do. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  5. 优化起搏参数在提高心脏再同步化治疗疗效中的作用%Study on significance of optimal pacemaker parameters in improving the efficacy of cardiac resynchronization therapy

    Institute of Scientific and Technical Information of China (English)

    谢芳; 何亚峰; 邓成钢; 程光辉; 张劲林

    2015-01-01

    Objective To evaluate the efficacy of cardiac resynchronization therapy( CRT)in treatment of patients with AV or VV delay. Methods Forty-nine patients with chronic heart failure received cardiac resynchronous pacing,followed-up for 1 week,3 months,6 months and 1 year,the delay of AV had been optimized by ultrasound cardiography,and delay of VV had been optimized by tissue Doppler imaging. Re-sults Heart function in 45 cases had been improved after CRT. According to NYHA classification,these patients had been improved from classⅢ˜IV to class II˜III,and their 6 minutes walking distance had also been increased. The LVEF index and VTI of left ventricular systolic func-tion had been improved( P <0. 01). Left ventricular diastolic filling time was also increased. In 3 months and 6 months after the treatment,left ventricular end diastolic diameter and volume were significantly smaller than those before the treatment( P <0. 01,P <0. 05). Mitral regurgita-tion had been reduced,and the standard deviation of 12 segments time to peak had been decreased from(139 ± 33)ms to(110 ± 40)ms( P <0. 01). Conclusion Optimization of the pacemaker parameters is needed in order to enhance the efficacy of CRT.%目的:探讨优化A-V、V-V间期在提高心脏再同步化治疗( CRT)中的疗效。方法49例CRT治疗的慢性心力衰竭患者,于术后1周、3个月、6个月和12个月进行个体化参数程控(在超声心动图指导下优化A-V间期,在组织多普勒显像下优化V-V间期),观察心脏同步性和心功能变化,达到CRT最佳治疗目的。结果临床症状:45例CRT后心功能得到改善,心功能NYHA分级,从Ⅲ˜Ⅳ级提高为Ⅱ˜Ⅲ级,6分钟步行距离增加。超声指标:反映左室收缩功能的指标左室射血分数( P <0.01)、血流速度积分( VTI)增加,反映左室舒张功能的指标左室舒张充盈时间延长,评价心腔大小指标改善,术后3、6个月左心室舒张末期内

  6. Optimal PMU Placement By Improved Particle Swarm Optimization

    DEFF Research Database (Denmark)

    Rather, Zakir Hussain; Liu, Leo; Chen, Zhe;

    2013-01-01

    This paper presents an improved method of binary particle swarm optimization (IBPSO) technique for optimal phasor measurement unit (PMU) placement in a power network for complete system observability. Various effective improvements have been proposed to enhance the efficiency and convergence rate...... of conventional particle swarm optimization method. The proposed method of IBPSO ensures optimal PMU placement with and without consideration of zero injection measurements. The proposed method has been applied to standard test systems like 17 bus, IEEE 24-bus, IEEE 30-bus, New England 39-bus, IEEE 57-bus system...

  7. An improved group search optimizer for mechanical design optimization problems

    Institute of Scientific and Technical Information of China (English)

    Hai Shen; Yunlong Zhu; Ben Niu; Q.H. Wu

    2009-01-01

    This paper presents an improved group search optimizer (iGSO) for solving mechanical design optimization problems.In the pro-posed algorithm,subpopulations and a co-operation evolutionary strategy were adopted to improve the global search capability and convergence performance.The iGSO is evaluated on two optimization problems of classical mechanical design:spring and pressure vessel.The experimental results are analyzed in comparison with those reported in the literatures.The results show that iGSO has much better convergence performance and is easier to implement in comparison with other existing evolutionary algorithms.

  8. Improving Topology Optimization using Games

    DEFF Research Database (Denmark)

    Nobel-Jørgensen, Morten; Christiansen, Asger Nyman; Bærentzen, J. Andreas

    free of charge on iOS and Android devices1. The TopOptGame is inspired by puzzle-games (a genre of computer games), which constantly challenges the players and gives rewards when progress is made. This engagement loop will take the player on a journey starting with simple problems with few supports......, this will allow us to analyze the data to measure human performance of topology optimization and more importantly, in which cases people's intuition succeed or fail. The game is currently a working prototype and is scheduled for final release on both iOS and Android before WCSMO-10....

  9. Improved Propulsion Modeling for Low-Thrust Trajectory Optimization

    Science.gov (United States)

    Knittel, Jeremy M.; Englander, Jacob A.; Ozimek, Martin T.; Atchison, Justin A.; Gould, Julian J.

    2017-01-01

    Low-thrust trajectory design is tightly coupled with spacecraft systems design. In particular, the propulsion and power characteristics of a low-thrust spacecraft are major drivers in the design of the optimal trajectory. Accurate modeling of the power and propulsion behavior is essential for meaningful low-thrust trajectory optimization. In this work, we discuss new techniques to improve the accuracy of propulsion modeling in low-thrust trajectory optimization while maintaining the smooth derivatives that are necessary for a gradient-based optimizer. The resulting model is significantly more realistic than the industry standard and performs well inside an optimizer. A variety of deep-space trajectory examples are presented.

  10. Optimizing significance testing of astronomical forcing in cyclostratigraphy

    Science.gov (United States)

    Kemp, David B.

    2016-12-01

    The recognition of astronomically forced (Milankovitch) climate cycles in geological archives marked a major advance in Earth science, revealing a heartbeat within the climate system of general importance and key utility. Power spectral analysis is the primary tool used to facilitate identification of astronomical cycles in stratigraphic data, but commonly employed methods for testing the statistical significance of relatively high narrow-band variance of potential astronomical origin in spectra have been criticized for inadequately balancing the respective probabilities of type I (false positive) and type II (false negative) errors. This has led to suggestions that the importance of astronomical forcing in Earth history is overstated. It can be readily demonstrated, however, that the imperfect nature of the stratigraphic record and the quasiperiodicity of astronomical cycles sets an upper limit on the attainable significance of astronomical signals. Optimized significance testing is that which minimizes the combined probability of type I and type II errors. Numerical simulations of stratigraphically preserved astronomical signals suggest that optimum significance levels at which to reject a null hypothesis of no astronomical forcing are between 0.01 and 0.001 (i.e., 99-99.9% confidence level). This is lower than commonly employed in the literature (90-99% confidence levels). Nevertheless, in consonance with the emergent view from other scientific disciplines, fixed-value null hypothesis significance testing of power spectra is implicitly ill suited to demonstrating astronomical forcing, and the use of spectral analysis remains a difficult and subjective endeavor in the absence of additional supporting evidence.

  11. Optimization and improvement of Halbach cylinder design

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Bahl, Christian Robert Haffenden; Smith, Anders;

    2008-01-01

    that this parameter was optimal for long Halbach cylinders with small rex. Using the previously mentioned additional blocks of magnets can improve the parameter by as much as 15% as well as improve the homogeneity of the field in the cylinder bore. ©2008 American Institute of Physics......In this paper we describe the results of a parameter survey of a 16 segmented Halbach cylinder in three dimensions in which the parameters internal radius, rin, external radius, rex, and length, L, have been varied. Optimal values of rex and L were found for a Halbach cylinder with the least...

  12. Improved aerodynamic design of turbomachinery bladings by numerical optimization

    Energy Technology Data Exchange (ETDEWEB)

    Burguburu, St.; Le Pape, A. [Office National d' Etudes et de Recherches Aerospatiales (ONERA), Applied Aerodynamics Dept. 29, 92 - Chatillon (France)

    2003-06-01

    The aerodynamic optimization of a transonic compressor is reported in this paper. The Q3D Navier-Stokes solver COLIBRI is coupled to a gradient-based method (CONMIN) and to a genetic algorithm (GADO). The suction side of a 2-D blade is optimized by using both optimization methods with a significant efficiency improvement. In 3-D, the performance improvement is obtained by modifying the suction surface of a transonic compressor with a Bezier surface and by using the CANARI solver coupled to the gradient method (CONMIN). (authors)

  13. Optimization and improvement of Halbach cylinder design

    CERN Document Server

    Bjørk, R; Smith, A; Pryds, N

    2014-01-01

    In this paper we describe the results of a parameter survey of a 16 segmented Halbach cylinder in three dimensions in which the parameters internal radius, $r_{\\mathrm{\\scriptsize{in}}}$, external radius, $r_{\\mathrm{\\scriptsize{ex}}}$, and length, $L$, have been varied. Optimal values of $r_{\\mathrm{\\scriptsize{ex}}}$ and $L$ were found for a Halbach cylinder with the least possible volume of magnets with a given mean flux density in the cylinder bore. The volume of the cylinder bore could also be significantly increase by only slightly increasing the volume of the magnets, for a fixed mean flux density. Placing additional blocks of magnets on the end faces of the Halbach cylinder also improved the mean flux density in the cylinder bore, especially so for short Halbach cylinders with large $r_{\\mathrm{\\scriptsize{ex}}}$. Moreover magnetic cooling as an application for Halbach cylinders was considered. A magnetic cooling quality parameter, $\\Lambda_{\\mathrm{cool}}$, was introduced and results showed that this...

  14. Improved Particle Swarm Optimization for Global Optimization of Unimodal and Multimodal Functions

    Science.gov (United States)

    Basu, Mousumi

    2016-12-01

    Particle swarm optimization (PSO) performs well for small dimensional and less complicated problems but fails to locate global minima for complex multi-minima functions. This paper proposes an improved particle swarm optimization (IPSO) which introduces Gaussian random variables in velocity term. This improves search efficiency and guarantees a high probability of obtaining the global optimum without significantly impairing the speed of convergence and the simplicity of the structure of particle swarm optimization. The algorithm is experimentally validated on 17 benchmark functions and the results demonstrate good performance of the IPSO in solving unimodal and multimodal problems. Its high performance is verified by comparing with two popular PSO variants.

  15. Optimal nutrition for improved twin pregnancy outcome.

    Science.gov (United States)

    Goodnight, William; Newman, Roger

    2009-11-01

    Twin pregnancies contribute a disproportionate degree to perinatal morbidity, partly because of increased risks of low birth weight and prematurity. Although the cause of the morbidity is multifactorial, attention to twin-specific maternal nutrition may be beneficial in achieving optimal fetal growth and birth weight. Achievement of body mass index (BMI)-specific weight gain goals, micronutrient and macronutrient supplementation specific to the physiology of twin gestations, and carbohydrate-controlled diets are recommended for optimal twin growth and pregnancy outcomes. The daily recommended caloric intake for normal-BMI women with twins is 40-45 kcal/kg each day, and iron, folate, calcium, magnesium, and zinc supplementation is recommended beyond a usual prenatal vitamin. Daily supplementation of docosahexaenoic acid and vitamin D should also be considered. Multiple gestation-specific prenatal care settings with a focus on nutritional interventions improve birth weight and length of gestation and should be considered for the care of women carrying multiples. Antepartum lactation consultation can also improve the rate of postpartum breastfeeding in twin pregnancies. Twin gestation-specific nutritional interventions seem effective in improving the outcome of these pregnancies and should be emphasized in the antepartum care of multiple gestations. This review examines the available evidence and offers recommendations for twin pregnancy-specific nutritional interventions.

  16. Energy efficiency improvement by gear shifting optimization

    Directory of Open Access Journals (Sweden)

    Blagojevic Ivan A.

    2013-01-01

    Full Text Available Many studies have proved that elements of driver’s behavior related to gear selection have considerable influence on the fuel consumption. Optimal gear shifting is a complex task, especially for inexperienced drivers. This paper presents an implemented idea for gear shifting optimization with the aim of fuel consumption minimization with more efficient engine working regimes. Optimized gear shifting enables the best possible relation between vehicle motion regimes and engine working regimes. New theoretical-experimental approach has been developed using On-Board Diagnostic technology which so far has not been used for this purpose. The matrix of driving modes according to which tests were performed is obtained and special data acquisition system and analysis process have been developed. Functional relations between experimental test modes and adequate engine working parameters have been obtained and all necessary operations have been conducted to enable their use as inputs for the designed algorithm. The created Model has been tested in real exploitation conditions on passenger car with Otto fuel injection engine and On-Board Diagnostic connection without any changes on it. The conducted tests have shown that the presented Model has significantly positive effects on fuel consumption which is an important ecological aspect. Further development and testing of the Model allows implementation in wide range of motor vehicles with various types of internal combustion engines.

  17. Significant improvements in long trace profiler measurement performance

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, P.Z. [Brookhaven National Lab., Upton, NY (United States); Bresloff, C.J. [Argonne National Lab., IL (United States)

    1996-07-01

    A Modifications made to the Long Trace Profiler (LTP II) system at the Advanced Photon Source at Argonne National Laboratory have significantly improved the accuracy and repeatability of the instrument The use of a Dove prism in the reference beam path corrects for phasing problems between mechanical efforts and thermally-induced system errors. A single reference correction now completely removes both error signals from the measured surface profile. The addition of a precision air conditioner keeps the temperature in the metrology enclosure constant to within {+-}0.1{degrees}C over a 24 hour period and has significantly improved the stability and repeatability of the system. We illustrate the performance improvements with several sets of measurements. The improved environmental control has reduced thermal drift error to about 0.75 microradian RMS over a 7.5 hour time period. Measurements made in the forward scan direction and the reverse scan direction differ by only about 0.5 microradian RMS over a 500mm, trace length. We are now able to put 1-sigma error bar of 0.3 microradian on an average of 10 slope profile measurements over a 500mm long trace length, and we are now able to put a 0.2 microradian error bar on an average of 10 measurements over a 200mm trace length. The corresponding 1-sigma height error bar for this measurement is 1.1 run.

  18. Accuracy of pitch matching significantly improved by live voice model.

    Science.gov (United States)

    Granot, Roni Y; Israel-Kolatt, Rona; Gilboa, Avi; Kolatt, Tsafrir

    2013-05-01

    Singing is, undoubtedly, the most fundamental expression of our musical capacity, yet an estimated 10-15% of Western population sings "out-of-tune (OOT)." Previous research in children and adults suggests, albeit inconsistently, that imitating a human voice can improve pitch matching. In the present study, we focus on the potentially beneficial effects of the human voice and especially the live human voice. Eighteen participants varying in their singing abilities were required to imitate in singing a set of nine ascending and descending intervals presented to them in five different randomized blocked conditions: live piano, recorded piano, live voice using optimal voice production, recorded voice using optimal voice production, and recorded voice using artificial forced voice production. Pitch and interval matching in singing were much more accurate when participants repeated sung intervals as compared with intervals played to them on the piano. The advantage of the vocal over the piano stimuli was robust and emerged clearly regardless of whether piano tones were played live and in full view or were presented via recording. Live vocal stimuli elicited higher accuracy than recorded vocal stimuli, especially when the recorded vocal stimuli were produced in a forced vocal production. Remarkably, even those who would be considered OOT singers on the basis of their performance when repeating piano tones were able to pitch match live vocal sounds, with deviations well within the range of what is considered accurate singing (M=46.0, standard deviation=39.2 cents). In fact, those participants who were most OOT gained the most from the live voice model. Results are discussed in light of the dual auditory-motor encoding of pitch analogous to that found in speech. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  19. Improvements To Glowworm Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Piotr Oramus

    2010-01-01

    Full Text Available Glowworm Swarm Optimization algorithm is applied for the simultaneous capture of multipleoptima of multimodal functions. The algorithm uses an ensemble of agents, which scan thesearch space and exchange information concerning a fitness of their current position. Thefitness is represented by a level of a luminescent quantity called luciferin. An agent movesin direction of randomly chosen neighbour, which broadcasts higher value of the luciferin.Unfortunately, in the absence of neighbours, the agent does not move at all. This is anunwelcome feature, because it diminishes the performance of the algorithm. Additionally,in the case of parallel processing, this feature can lead to unbalanced loads. This paperpresents simple modifications of the original algorithm, which improve performance of thealgorithm by limiting situations, in which the agent cannot move. The paper provides resultsof comparison of an original and modified algorithms calculated for several multimodal testfunctions.

  20. Improving MEME via a two-tiered significance analysis.

    Science.gov (United States)

    Tanaka, Emi; Bailey, Timothy L; Keich, Uri

    2014-07-15

    With over 9000 unique users recorded in the first half of 2013, MEME is one of the most popular motif-finding tools available. Reliable estimates of the statistical significance of motifs can greatly increase the usefulness of any motif finder. By analogy, it is difficult to imagine evaluating a BLAST result without its accompanying E-value. Currently MEME evaluates its EM-generated candidate motifs using an extension of BLAST's E-value to the motif-finding context. Although we previously indicated the drawbacks of MEME's current significance evaluation, we did not offer a practical substitute suited for its needs, especially because MEME also relies on the E-value internally to rank competing candidate motifs. Here we offer a two-tiered significance analysis that can replace the E-value in selecting the best candidate motif and in evaluating its overall statistical significance. We show that our new approach could substantially improve MEME's motif-finding performance and would also provide the user with a reliable significance analysis. In addition, for large input sets, our new approach is in fact faster than the currently implemented E-value analysis. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. Improving topology optimization intuition through games

    DEFF Research Database (Denmark)

    Nobel-Jørgensen, Morten; Malmgren-Hansen, David; Bærentzen, J. Andreas

    2016-01-01

    This paper describes the educational game, TopOpt Game, which invites the player to solve various optimization challenges. The main purpose of gamifying topology optimization is to create a supplemental educational tool which can be used to introduce concepts of topology optimization to newcomers...

  2. Training Significantly Improves Fetoscopy Performance: A Pilot Randomized Controlled Trial.

    Science.gov (United States)

    Mietzsch, Stefan; Boettcher, Johannes; Yang, Sisi; Chantereau, Pierre; Romero, Philip; Bergholz, Robert; Reinshagen, Konrad; Boettcher, Michael

    2016-10-01

    Background Implementation of complex fetoscopic procedures that included intracorporeal suturing has been limited due to technical difficulties that might be surmounted with adequate training. Evaluating the impact of laparoscopic or fetoscopic training on fetoscopic performance was the aim of this study. Methods To evaluate fetoscopic performance after either laparoscopic or fetoscopic training, subjects were asked to perform four surgeon's square knots fetoscopically prior and post 2 hours of hands-on training. All subjects were medical students and novice in laparoscopic and fetoscopic interventions. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality, and fetoscopic performance were assessed. Results Forty-six subjects were included in the study; after simple randomization, 24 were trained fetoscopically and 22 laparoscopically. Both groups had comparable baseline characteristics and improved after training significantly regarding all aspects assessed in this study. Subjects who trained fetoscopically were superior in terms of suturing and knot-tying performance. Conclusion Training significantly improves fetoscopic performance and may indeed be the keystone for future complex fetoscopic interventions. It seems advisable to train rather fetoscopically than laparoscopically resulting in higher suture and knot-tying quality. Georg Thieme Verlag KG Stuttgart · New York.

  3. Evolutionary optimization of kernel weights improves protein complex comembership prediction.

    Science.gov (United States)

    Hulsman, Marc; Reinders, Marcel J T; de Ridder, Dick

    2009-01-01

    In recent years, more and more high-throughput data sources useful for protein complex prediction have become available (e.g., gene sequence, mRNA expression, and interactions). The integration of these different data sources can be challenging. Recently, it has been recognized that kernel-based classifiers are well suited for this task. However, the different kernels (data sources) are often combined using equal weights. Although several methods have been developed to optimize kernel weights, no large-scale example of an improvement in classifier performance has been shown yet. In this work, we employ an evolutionary algorithm to determine weights for a larger set of kernels by optimizing a criterion based on the area under the ROC curve. We show that setting the right kernel weights can indeed improve performance. We compare this to the existing kernel weight optimization methods (i.e., (regularized) optimization of the SVM criterion or aligning the kernel with an ideal kernel) and find that these do not result in a significant performance improvement and can even cause a decrease in performance. Results also show that an expert approach of assigning high weights to features with high individual performance is not necessarily the best strategy.

  4. Perspective texture synthesis based on improved energy optimization.

    Directory of Open Access Journals (Sweden)

    Syed Muhammad Arsalan Bashir

    Full Text Available Perspective texture synthesis has great significance in many fields like video editing, scene capturing etc., due to its ability to read and control global feature information. In this paper, we present a novel example-based, specifically energy optimization-based algorithm, to synthesize perspective textures. Energy optimization technique is a pixel-based approach, so it's time-consuming. We improve it from two aspects with the purpose of achieving faster synthesis and high quality. Firstly, we change this pixel-based technique by replacing the pixel computation with a little patch. Secondly, we present a novel technique to accelerate searching nearest neighborhoods in energy optimization. Using k- means clustering technique to build a search tree to accelerate the search. Hence, we make use of principal component analysis (PCA technique to reduce dimensions of input vectors. The high quality results prove that our approach is feasible. Besides, our proposed algorithm needs shorter time relative to other similar methods.

  5. An improved marriage in honey bees optimization algorithm for single objective unconstrained optimization.

    Science.gov (United States)

    Celik, Yuksel; Ulker, Erkan

    2013-01-01

    Marriage in honey bees optimization (MBO) is a metaheuristic optimization algorithm developed by inspiration of the mating and fertilization process of honey bees and is a kind of swarm intelligence optimizations. In this study we propose improved marriage in honey bees optimization (IMBO) by adding Levy flight algorithm for queen mating flight and neighboring for worker drone improving. The IMBO algorithm's performance and its success are tested on the well-known six unconstrained test functions and compared with other metaheuristic optimization algorithms.

  6. Improved extremal optimization for the asymmetric traveling salesman problem

    Science.gov (United States)

    Chen, Yu-Wang; Zhu, Yao-Jia; Yang, Gen-Ke; Lu, Yong-Zai

    2011-11-01

    This paper presents an improved extremal optimization (IEO) algorithm for solving the asymmetric traveling salesman problem (ATSP). At each update step, the IEO algorithm proceeds through two main steps: extremal dynamics and cooperative optimization. As an improvement of extremal optimization (EO), the IEO provides a general combinatorial optimization framework by emphasizing the step of cooperative optimization. In the paper, an effective cooperative optimization strategy with combination of greedy search and random walk is designed in terms of the microscopic characteristics of the ATSP solutions. Simulation results on a set of benchmark ATSP instances show that the proposed IEO algorithm provides satisfactory performance on computational effectiveness and efficiency.

  7. Sootblowing optimization for improved boiler performance

    Science.gov (United States)

    James, John Robert; McDermott, John; Piche, Stephen; Pickard, Fred; Parikh, Neel J

    2013-07-30

    A sootblowing control system that uses predictive models to bridge the gap between sootblower operation and boiler performance goals. The system uses predictive modeling and heuristics (rules) associated with different zones in a boiler to determine an optimal sequence of sootblower operations and achieve boiler performance targets. The system performs the sootblower optimization while observing any operational constraints placed on the sootblowers.

  8. Improving topology optimization intuition through games

    DEFF Research Database (Denmark)

    Nobel-Jørgensen, Morten; Malmgren-Hansen, David; Bærentzen, J. Andreas

    2016-01-01

    This paper describes the educational game, TopOpt Game, which invites the player to solve various optimization challenges. The main purpose of gamifying topology optimization is to create a supplemental educational tool which can be used to introduce concepts of topology optimization to newcomers...... that players achieve higher scores the more they play the game. The game is freely available for the iOS platform at Apple's App Store and at http://www.topopt.dtu.dk/?q=node/909 for Win-dows and OSX....

  9. Global optimization for ducted coaxial-rotors aircraft based on Kriging model and improved particle swarm optimization algorithm

    Institute of Scientific and Technical Information of China (English)

    杨璐鸿; 刘顺安; 张冠宇; 王春雪

    2015-01-01

    To improve the operational efficiency of global optimization in engineering, Kriging model was established to simplify the mathematical model for calculations. Ducted coaxial-rotors aircraft was taken as an example and Fluent software was applied to the virtual prototype simulations. Through simulation sample points, the total lift of the ducted coaxial-rotors aircraft was obtained. The Kriging model was then constructed, and the function was fitted. Improved particle swarm optimization (PSO) was also utilized for the global optimization of the Kriging model of the ducted coaxial-rotors aircraft for the determination of optimized global coordinates. Finally, the optimized results were simulated by Fluent. The results show that the Kriging model and the improved PSO algorithm significantly improve the lift performance of ducted coaxial-rotors aircraft and computer operational efficiency.

  10. Recent Improvements to the Copernicus Trajectory Design and Optimization System

    Science.gov (United States)

    Williams, Jacob; Senent, Juan S.; Ocampo, Cesar; Lee, David E.

    2012-01-01

    Copernicus is a software tool for spacecraft trajectory design and optimization. The latest version (v3.0.1) was released in October 2011. It is available at no cost to NASA centers, government contractors, and organizations with a contractual affiliation with NASA. This paper is a brief overview of the recent development history of Copernicus. An overview of the evolution of the software and a discussion of significant new features and improvements is given, and how the tool is used to design spacecraft missions

  11. Improving resource utilization in hierarchy network by optimizing topological structure

    Science.gov (United States)

    Liu, G. L.; Peng, H. P.; Li, L. X.; Sun, F.; Yang, Y. X.

    2012-02-01

    We study the performance of peer-to-peer (P2P) network built on the top of hierarchy topological structure of local area networks (LAN). We find that the topological structure of the underlying physical network has significant impacts on the resource utilization of the P2P overlay network. The larger size of the physical network is, the lower resource utilization of the overlay network is. Through optimizing the topological structure of physical network, we propose two novel schemes to improve the resource utilization. The experimental results show that in any case the resource utilization of P2P network can always achieve 100% by these two schemes.

  12. Methylphenidate significantly improves declarative memory functioning of adults with ADHD.

    NARCIS (Netherlands)

    Verster, J.C.; Bekker, E.M.; Kooij, J.J.; Buitelaar, J.K.; Verbaten, M.N.; Volkerts, E.R.; Olivier, B.

    2010-01-01

    BACKGROUND: Declarative memory deficits are common in untreated adults with attention-deficit hyperactivity disorder (ADHD), but limited evidence exists to support improvement after treatment with methylphenidate. The objective of this study was to examine the effects of methylphenidate on memory fu

  13. An Improved Marriage in Honey Bees Optimization Algorithm for Single Objective Unconstrained Optimization

    Directory of Open Access Journals (Sweden)

    Yuksel Celik

    2013-01-01

    Full Text Available Marriage in honey bees optimization (MBO is a metaheuristic optimization algorithm developed by inspiration of the mating and fertilization process of honey bees and is a kind of swarm intelligence optimizations. In this study we propose improved marriage in honey bees optimization (IMBO by adding Levy flight algorithm for queen mating flight and neighboring for worker drone improving. The IMBO algorithm’s performance and its success are tested on the well-known six unconstrained test functions and compared with other metaheuristic optimization algorithms.

  14. Declining numbers of pancreas transplantations but significant improvements in outcome.

    Science.gov (United States)

    Gruessner, A C; Gruessner, R W G

    2014-01-01

    In the United States, over the past 8 years, the number of pancreas transplantations has steadily declined. This decline comes as a surprise, because patient and graft outcomes have substantially improved during the same period of time. Patient survival rates at 1 year in all 3 recipient categories are >96%; graft survival rates are 82%-89%. Changes in immunosuppressive therapy have had a positive impact on outcome, as have better pancreas donor and recipient selection criteria and refined post-transplantation patient care. Although different factors may have contributed to the declining pancreas transplantation numbers, a more effective process of publicly promoting and widely communicating the improved results of pancreas transplantation is warranted.

  15. A significantly improved membrane for vanadium redox flow battery

    Science.gov (United States)

    Jia, Chuankun; Liu, Jianguo; Yan, Chuanwei

    A novel sandwich-type sulfonated poly(ether ether ketone) (SPEEK)/tungstophosphoric acid (TPA)/polypropylene (PP) composite membrane for a vanadium redox flow battery (VRB) has been developed with improved properties: the permeability of vanadium ions is greatly reduced and the performance of the VRB cell is greatly increased. The membrane is based on a traditional SPEEK membrane embedded with TPA but PP is used to enhance the membrane for the first time. Although its voltage efficiency (VE) is a little lower than that of a Nafion 212 membrane, it is expected to have good prospects for VRB systems because of its low cost and good performance.

  16. An Improved Particle Swarm Optimization for Feature Selection

    Institute of Scientific and Technical Information of China (English)

    Yuanning Liu; Gang Wang; Huiling Chen; Hao Dong; Xiaodong Zhu; Sujing Wang

    2011-01-01

    Particle Swarm Optimization (PSO) is a popular and bionic algorithm based on the social behavior associated with bird flocking for optimization problems. To maintain the diversity of swarms, a few studies of multi-swarm strategy have been reported. However, the competition among swarms, reservation or destruction of a swarm, has not been considered further. In this paper, we formulate four rules by introducing the mechanism for survival of the fittest, which simulates the competition among the swarms. Based on the mechanism, we design a modified Multi-Swarm PSO (MSPSO) to solve discrete problems,which consists of a number of sub-swarms and a multi-swarm scheduler that can monitor and control each sub-swarm using the rules. To further settle the feature selection problems, we propose an Improved Feature Selection (IFS) method by integrating MSPSO, Support Vector Machines (SVM) with F-score method. The IFS method aims to achieve higher generalization capability through performing kernel parameter optimization and feature selection simultaneously. The performance of the proposed method is compared with that of the standard PSO based, Genetic Algorithm (GA) based and the grid search based methods on 10 benchmark datasets, taken from UCI machine learning and StatLog databases. The numerical results and statistical analysis show that the proposed IFS method performs significantly better than the other three methods in terms of prediction accuracy with smaller subset of features.

  17. Knee dermolipectomy: a simple operation with significant functional improvement.

    Science.gov (United States)

    Bertheuil, N; Huguier, V; Beuzeboc, M; Aillet, S; Watier, E

    2013-02-01

    Obesity is a major public health problem in Western societies. It may lead to difficulties in daily life that have an impact on quality of life and create psychological disorders. After failure of diet and exercise, patients can undergo bariatric surgery, but some obese patients are not motivated to undergo a bariatric procedure. For such patients, plastic surgeons can correct some excess fat to improve their quality of life. This report describes an original technique for correcting the excess fat at the medial part of the knees to regain a normal walking perimeter. A 68-year-old woman was admitted to the authors' center for correction of a functional walking disorder. Indeed, her clinical examination found a static disorder, with a valgus knee morphotype related to a major excess of skin and fat in the medial part of the knees. She underwent a knee dermolipectomy to obtain a solely functional result. No complications were observed in the woman's postoperative course. At this writing, the result is stable 18 months after the surgical procedure, with a minimal visible scar hidden in the internal face of the knees. The woman has experienced a loss of her genu valgum and regained a walking distance longer than 1 km. She also has lost 10 kg of weight. Knee dermolipectomy is a simple procedure with good results and few complications that improves the quality of life for obese patients. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  18. Improving biconnectivity approximation via local optimization

    Energy Technology Data Exchange (ETDEWEB)

    Ka Wong Chong; Tak Wah Lam [Univ. of Hong Kong (Hong Kong)

    1996-12-31

    The problem of finding the minimum biconnected spanning subgraph of an undirected graph is NP-hard. A lot of effort has been made to find biconnected spanning subgraphs that approximate to the minimum one as close as possible. Recently, new polynomial-time (sequential) approximation algorithms have been devised to improve the approximation factor from 2 to 5/3 , then 3/2, while NC algorithms have also been known to achieve 7/4 + {epsilon}. This paper presents a new technique which can be used to further improve parallel approximation factors to 5/3 + {epsilon}. In the sequential context, the technique reveals an algorithm with a factor of {alpha} + 1/5, where a is the approximation factor of any 2-edge connectivity approximation algorithm.

  19. Improved Modeling of Intelligent Tutoring Systems Using Ant Colony Optimization

    Science.gov (United States)

    Rastegarmoghadam, Mahin; Ziarati, Koorush

    2017-01-01

    Swarm intelligence approaches, such as ant colony optimization (ACO), are used in adaptive e-learning systems and provide an effective method for finding optimal learning paths based on self-organization. The aim of this paper is to develop an improved modeling of adaptive tutoring systems using ACO. In this model, the learning object is…

  20. A designer bleomycin with significantly improved DNA cleavage activity.

    Science.gov (United States)

    Huang, Sheng-Xiong; Feng, Zhiyang; Wang, Liyan; Galm, Ute; Wendt-Pienkowski, Evelyn; Yang, Dong; Tao, Meifeng; Coughlin, Jane M; Duan, Yanwen; Shen, Ben

    2012-08-15

    The bleomycins (BLMs) are used clinically in combination with a number of other agents for the treatment of several types of tumors, and the BLM, etoposide, and cisplatin treatment regimen cures 90-95% of metastatic testicular cancer patients. BLM-induced pneumonitis is the most feared, dose-limiting side effect of BLM in chemotherapy, which can progress into lung fibrosis and affect up to 46% of the total patient population. There have been continued efforts to develop new BLM analogues in the search for anticancer drugs with better clinical efficacy and lower lung toxicity. We have previously cloned and characterized the biosynthetic gene clusters for BLMs from Streptomyces verticillus ATCC15003, tallysomycins from Streptoalloteichus hindustanus E465-94 ATCC31158, and zorbamycin (ZBM) from Streptomyces flavoviridis SB9001. Comparative analysis of the three biosynthetic machineries provided the molecular basis for the formulation of hypotheses to engineer novel analogues. We now report engineered production of three new analogues, 6'-hydroxy-ZBM, BLM Z, and 6'-deoxy-BLM Z and the evaluation of their DNA cleavage activities as a measurement for their potential anticancer activity. Our findings unveiled: (i) the disaccharide moiety plays an important role in the DNA cleavage activity of BLMs and ZBMs, (ii) the ZBM disaccharide significantly enhances the potency of BLM, and (iii) 6'-deoxy-BLM Z represents the most potent BLM analogue known to date. The fact that 6'-deoxy-BLM Z can be produced in reasonable quantities by microbial fermentation should greatly facilitate follow-up mechanistic and preclinical studies to potentially advance this analogue into a clinical drug.

  1. Improved Quantum Particle Swarm Optimization for Mangroves Classification

    Directory of Open Access Journals (Sweden)

    Zhehuang Huang

    2016-01-01

    Full Text Available Quantum particle swarm optimization (QPSO is a population based optimization algorithm inspired by social behavior of bird flocking which combines the ideas of quantum computing. For many optimization problems, traditional QPSO algorithm can produce high-quality solution within a reasonable computation time and relatively stable convergence characteristics. But QPSO algorithm also showed some unsatisfactory issues in practical applications, such as premature convergence and poor ability in global optimization. To solve these problems, an improved quantum particle swarm optimization algorithm is proposed and implemented in this paper. There are three main works in this paper. Firstly, an improved QPSO algorithm is introduced which can enhance decision making ability of the model. Secondly, we introduce synergetic neural network model to mangroves classification for the first time which can better handle fuzzy matching of remote sensing image. Finally, the improved QPSO algorithm is used to realize the optimization of network parameter. The experiments on mangroves classification showed that the improved algorithm has more powerful global exploration ability and faster convergence speed.

  2. Trust regions in Kriging-based optimization with expected improvement

    Science.gov (United States)

    Regis, Rommel G.

    2016-06-01

    The Kriging-based Efficient Global Optimization (EGO) method works well on many expensive black-box optimization problems. However, it does not seem to perform well on problems with steep and narrow global minimum basins and on high-dimensional problems. This article develops a new Kriging-based optimization method called TRIKE (Trust Region Implementation in Kriging-based optimization with Expected improvement) that implements a trust-region-like approach where each iterate is obtained by maximizing an Expected Improvement (EI) function within some trust region. This trust region is adjusted depending on the ratio of the actual improvement to the EI. This article also develops the Kriging-based CYCLONE (CYClic Local search in OptimizatioN using Expected improvement) method that uses a cyclic pattern to determine the search regions where the EI is maximized. TRIKE and CYCLONE are compared with EGO on 28 test problems with up to 32 dimensions and on a 36-dimensional groundwater bioremediation application in appendices supplied as an online supplement available at http://dx.doi.org/10.1080/0305215X.2015.1082350. The results show that both algorithms yield substantial improvements over EGO and they are competitive with a radial basis function method.

  3. An improved optimal elemental method for updating finite element models

    Institute of Scientific and Technical Information of China (English)

    Duan Zhongdong(段忠东); Spencer B.F.; Yan Guirong(闫桂荣); Ou Jinping(欧进萍)

    2004-01-01

    The optimal matrix method and optimal elemental method used to update finite element models may not provide accurate results. This situation occurs when the test modal model is incomplete, as is often the case in practice. An improved optimal elemental method is presented that defines a new objective function, and as a byproduct, circumvents the need for mass normalized modal shapes, which are also not readily available in practice. To solve the group of nonlinear equations created by the improved optimal method, the Lagrange multiplier method and Matlab function fmincon are employed. To deal with actual complex structures,the float-encoding genetic algorithm (FGA) is introduced to enhance the capability of the improved method. Two examples, a 7-degree of freedom (DOF) mass-spring system and a 53-DOF planar frame, respectively, are updated using the improved method.Thc example results demonstrate the advantages of the improved method over existing optimal methods, and show that the genetic algorithm is an effective way to update the models used for actual complex structures.

  4. [Research on improving spectrum resolution of optimized Wollaston prism array].

    Science.gov (United States)

    Zhang, Peng; Wang, Jian-Rong; Zhang, Guo-Chen; Hou, Wen

    2011-11-01

    In order to not affect the image quality of interference fringes on the basis of the structure by increasing the structure angle of Wollaston prism to improve spectrum resolution, the authors optimized the structure of Wollaston prism. Calculating the function of the splitting angle and the structure angle, analysis indicated that taking the isosceles triangle prism with the same nature of the second wedge-shaped prism after the Wollaston prism, which makes the o and e light parallel to the optical axis, and alpha=0 degrees, the imaging interference fringes are no longer affected by changes in the splitting angle. Several optimized Wollaston prisms were made as an array to improve the spectral resolution. Experiments used traditional and optimized Wollaston prism array to detect the spectrum of the 980 nm laser. Experimental data showed that using optimized Wollaston prism array gets a clearer contrast of interference fringes, and the spectral data with Fourier transform are more accurate with DSP.

  5. LGMS-FOA: An Improved Fruit Fly Optimization Algorithm for Solving Optimization Problems

    Directory of Open Access Journals (Sweden)

    Dan Shan

    2013-01-01

    Full Text Available Recently, a new fruit fly optimization algorithm (FOA is proposed to solve optimization problems. In this paper, we empirically study the performance of FOA. Six different nonlinear functions are selected as testing functions. The experimental results illustrate that FOA cannot solve complex optimization problems effectively. In order to enhance the performance of FOA, an improved FOA (named LGMS-FOA is proposed. Simulation results and comparisons of LGMS-FOA with FOA and other metaheuristics show that LGMS-FOA can greatly enhance the searching efficiency and greatly improve the searching quality.

  6. An Improved Particle Swarm Optimization for Traveling Salesman Problem

    Science.gov (United States)

    Liu, Xinmei; Su, Jinrong; Han, Yan

    In allusion to particle swarm optimization being prone to get into local minimum, an improved particle swarm optimization algorithm is proposed. The algorithm draws on the thinking of the greedy algorithm to initialize the particle swarm. Two swarms are used to optimize synchronously. Crossover and mutation operators in genetic algorithm are introduced into the new algorithm to realize the sharing of information among swarms. We test the algorithm with Traveling Salesman Problem with 14 nodes and 30 nodes. The result shows that the algorithm can break away from local minimum earlier and it has high convergence speed and convergence ratio.

  7. Support Vector Machine Optimized by Improved Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Xiang Chang Sheng

    2013-07-01

    Full Text Available Parameters of support vector machines (SVM which is optimized by standard genetic algorithm is easy to trap into the local minimum, in order to get the optimal parameters of support vector machine, this paper proposed a parameters optimization method for support vector machines based on improved genetic algorithm, the simulation experiment is carried out on 5 benchmark datasets. The simulation show that the proposed method not only can assure the classification precision, but also can reduce training time markedly compared with standard genetic algorithm.

  8. Optimizing municipal wastewater treatment plants using an improved multi-objective optimization method.

    Science.gov (United States)

    Zhang, Rui; Xie, Wen-Ming; Yu, Han-Qing; Li, Wen-Wei

    2014-04-01

    An improved multi-objective optimization (MOO) model was established and used for simultaneously optimizing the treatment cost and multiple effluent quality indexes (including effluent COD, NH4(+)-N, NO3(-)-N) of a municipal wastewater treatment plant (WWTP). Compared with previous models that were mainly based on the use of fixed decision factors and did not taken into account the treatment cost, this model introduces a relationship model based on back propagation algorithm to determine the set of decision factors according to the expected optimization targets. Thus, a more flexible and precise optimization of the treatment process was allowed. Moreover, a MOO of conflicting objectives (i.e., treatment cost and effluent quality) was achieved. Applying this method, an optimal balance between operating cost and effluent quality of a WWTP can be found. This model may offer a useful tool for optimized design and control of practical WWTPs.

  9. Improved hybrid optimization algorithm for 3D protein structure prediction.

    Science.gov (United States)

    Zhou, Changjun; Hou, Caixia; Wei, Xiaopeng; Zhang, Qiang

    2014-07-01

    A new improved hybrid optimization algorithm - PGATS algorithm, which is based on toy off-lattice model, is presented for dealing with three-dimensional protein structure prediction problems. The algorithm combines the particle swarm optimization (PSO), genetic algorithm (GA), and tabu search (TS) algorithms. Otherwise, we also take some different improved strategies. The factor of stochastic disturbance is joined in the particle swarm optimization to improve the search ability; the operations of crossover and mutation that are in the genetic algorithm are changed to a kind of random liner method; at last tabu search algorithm is improved by appending a mutation operator. Through the combination of a variety of strategies and algorithms, the protein structure prediction (PSP) in a 3D off-lattice model is achieved. The PSP problem is an NP-hard problem, but the problem can be attributed to a global optimization problem of multi-extremum and multi-parameters. This is the theoretical principle of the hybrid optimization algorithm that is proposed in this paper. The algorithm combines local search and global search, which overcomes the shortcoming of a single algorithm, giving full play to the advantage of each algorithm. In the current universal standard sequences, Fibonacci sequences and real protein sequences are certified. Experiments show that the proposed new method outperforms single algorithms on the accuracy of calculating the protein sequence energy value, which is proved to be an effective way to predict the structure of proteins.

  10. Improved symbiotic organisms search algorithm for solving unconstrained function optimization

    Directory of Open Access Journals (Sweden)

    Sukanta Nama

    2016-09-01

    Full Text Available Recently, Symbiotic Organisms Search (SOS algorithm is being used for solving complex problems of optimization. This paper proposes an Improved Symbiotic Organisms Search (I-SOS algorithm for solving different complex unconstrained global optimization problems. In the improved algorithm, a random weighted reflective parameter and predation phase are suggested to enhance the performance of the algorithm. The performances of this algorithm are compared with the other state-of-the-art algorithms. The parametric study of the common control parameter has also been performed.

  11. MULTICHANNEL COGNITIVE CROSS LAYER OPTIMIZATION FOR IMPROVED VIDEO TRANSMISSION

    Directory of Open Access Journals (Sweden)

    Manimekalai Thirunavukkarasu

    2013-01-01

    Full Text Available Multimedia applications particularly real-time video transmission in wireless networks, envisions end to end user perceived video quality as an important QoS parameter to be achieved. Cognitive Radio promising efficient spectrum utilization combined with Cross layer optimization is seen as a powerful combination to achieve the desired video quality. This study proposes Optimal Channel Sensed Multichannel Cognitive MAC (OCSM-CMAC, a QoS driven cross layer system for the joint optimization of different network parameters along the network protocol stack for the improved video transmission. The primary network activity and wireless propagation dependent channel quality are modeled. Depending on the availability of the primary channel and channel condition as provided by an optimal sensing scheme and the encoder parameter in the application layer, cognitive MAC scheduling and PHY layer modulation and coding for the secondary user are optimized to achieve the required QoS. The simulation of channel and the cognitive user activity is done in MATLAB, while the application video coding is performed by H.264/AVC JM 15.1 codec to obtain the results. The results of the proposed OCSM-CMAC scheme demonstrate that improved PSNR and delay performance is achieved under the optimal channel sensing scheme compared to the random sensing scheme.

  12. Optimal Reactive Power Dispatch using Improved Differential Evolution Algorithm

    Directory of Open Access Journals (Sweden)

    Hamid Falaghi

    2014-12-01

    Full Text Available Reactive power dispatch plays a key role in secure and economic operation of power systems. Optimal reactive power dispatch (ORPD is a non-linear optimization problem which includes both continues and discrete variables. Due to complex characteristics, heuristic and evolutionary based optimization approaches have become effective tools to solve the ORPD problem. In this paper, a new optimization approach based on improved differential evolution (IDE has been proposed to solve the ORPD problem. IDE is an improved version of differential evolution optimization algorithm in which new solutions are produced in respect to global best solution. In the proposed approach, IDE determines the optimal combination of control variables including generator voltages, transformer taps and setting of VAR compensation devices to obtain minimum real power losses. In order to demonstrate the applicability and efficiency of the proposed IDE based approach, it has been tested on the IEEE 14 and 57-bus test systems and obtained results are compared with those obtained using other existing methods. Simulation results show that the proposed approach is superior to the other existing methods.

  13. An Improved Particle Swarm Optimization Algorithm Based on Ensemble Technique

    Institute of Scientific and Technical Information of China (English)

    SHI Yan; HUANG Cong-ming

    2006-01-01

    An improved particle swarm optimization (PSO) algorithm based on ensemble technique is presented. The algorithm combines some previous best positions (pbest) of the particles to get an ensemble position (Epbest), which is used to replace the global best position (gbest). It is compared with the standard PSO algorithm invented by Kennedy and Eberhart and some improved PSO algorithms based on three different benchmark functions. The simulation results show that the improved PSO based on ensemble technique can get better solutions than the standard PSO and some other improved algorithms under all test cases.

  14. Application of Improved Genetic Algorithm in PID Controller Parameters Optimization

    Directory of Open Access Journals (Sweden)

    Ying Chen

    2013-01-01

    Full Text Available Ying Chen, Yong-jie Ma, Wen-xia Yun College of Physics and Electronic Engineering, Northwest Normal University, Anning Road no.967 ,Lanzhou,China,0931-7971503 e-mail:chenying1386685@126.com Abstract The setting and optimization of Proportion Integration Differentiation(PID parameters have been always the important study topics in the automatic control field. The current optimization design methods are often difficult to consider the system requirements for quickness ,reliability and robustness .So a method of PID controller parameters optimization based on Improved Genetic Algorithm(IGA is presented .Simulations with Matlab have proved that the control performance index based on IGA is better than that of the GA method and Z-N method, and is a method which has good practical value of the PID parameter setting and optimization .

  15. Topology Optimization - Improved Checker-Board Filtering With Sharp Contours

    DEFF Research Database (Denmark)

    Pedersen, Christian Gejl; Lund, Jeppe Jessen; Damkilde, Lars

    2006-01-01

    In topology optimization it is mandatory to use a filtering technique in order to prevent checker-boarder solutions. The paper examines a new filtering principle and demonstrates an improved sharpness in the contours. This was not realized in the original proposal of the filter. Furthermore...

  16. A new support vector machine optimized by improved particle swarm optimization and its application

    Institute of Scientific and Technical Information of China (English)

    LI Xiang; YANG Shang-dong; QI Jian-xun

    2006-01-01

    A new support vectormachine (SVM) optimized by an improved particle swarm optimization (PSO)combined with simulated annealing algorithm (SA) was proposed. By incorporating with the simulated annealing method, the global searching capacity of the particle swarm optimization(SAPSO) was enchanced, and the searching capacity of the particle swarm optimization was studied. Then, the improved particle swarm optimization algorithm was used to optimize the parameters of SVM (c, σ and ε). Based on the operational data provided by a regional power grid in north China, the method was used in the actual short term load forecasting. The results show that compared to the PSO-SVM and the traditional SVM, the average time of the proposed method in the experimental process reduces by 11.6 s and 31.1 s, and the precision of the proposed method increases by 1.24% and 3.18%, respectively. So, the improved method is better than the PSO-SVM and the traditional SVM.

  17. Improving Mathematical Optimization Techniques with the Aid of Exergy-Based Variables

    Directory of Open Access Journals (Sweden)

    George Tsatsaronis

    2009-06-01

    Full Text Available

    The design optimization of energy conversion plants requires sophisticated optimization techniques. The usefulness of mathematical programming approaches has been discussed in several papers. Usually, the quality of the computed solutions, concerning global optimality and the convergence speed, is not discussed in these papers and even the existence of local optimal solutions is not mentioned. Indeed, the optimization of nonconvex mixed integer non-linear problems (MINLP, such as the structural and design optimization of power plants, is a very difficult problem. However, knowledge of the real optimization potential can assist the design engineer in better understanding the optimization procedure. This article deals with the use of exergetic variables for improving the quality of results obtained from mathematical optimization techniques and their convergence speed. LaGO, the solver used to compute the discussed results, can evaluate the obtained solution of the discussed minimization problems by calculating lower bounds of the original problem based on a relaxed convex objective function. Here, the use of exergetic variables can help to increase the lower bounds significantly and thus, to improve the evaluation of the computed solutions and the convergence speed. The method is applied to different optimization tasks.

    • This paper is an updated version of a paper published in the ECOS'08 proceedings. 

  18. Improvement of Interior Ballistic Performance Utilizing Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Hazem El Sadek

    2014-01-01

    Full Text Available This paper investigates the interior ballistic propelling charge design using the optimization methods to select the optimum charge design and to improve the interior ballistic performance. The propelling charge consists of a mixture propellant of seven-perforated granular propellant and one-hole tubular propellant. The genetic algorithms and some other evolutionary algorithms have complex evolution operators such as crossover, mutation, encoding, and decoding. These evolution operators have a bad performance represented in convergence speed and accuracy of the solution. Hence, the particle swarm optimization technique is developed. It is carried out in conjunction with interior ballistic lumped-parameter model with the mixture propellant. This technique is applied to both single-objective and multiobjective problems. In the single-objective problem, the optimization results are compared with genetic algorithm and the experimental results. The particle swarm optimization introduces a better performance of solution quality and convergence speed. In the multiobjective problem, the feasible region provides a set of available choices to the charge’s designer. Hence, a linear analysis method is adopted to give an appropriate set of the weight coefficients for the objective functions. The results of particle swarm optimization improved the interior ballistic performance and provided a modern direction for interior ballistic propelling charge design of guided projectile.

  19. Improved simple optimization (SOPT algorithm for unconstrained non-linear optimization problems

    Directory of Open Access Journals (Sweden)

    J. Thomas

    2016-09-01

    Full Text Available In the recent years, population based meta-heuristic are developed to solve non-linear optimization problems. These problems are difficult to solve using traditional methods. Simple optimization (SOPT algorithm is one of the simple and efficient meta-heuristic techniques to solve the non-linear optimization problems. In this paper, SOPT is compared with some of the well-known meta-heuristic techniques viz. Artificial Bee Colony algorithm (ABC, Particle Swarm Optimization (PSO, Genetic Algorithm (GA and Differential Evolutions (DE. For comparison, SOPT algorithm is coded in MATLAB and 25 standard test functions for unconstrained optimization having different characteristics are run for 30 times each. The results of experiments are compared with previously reported results of other algorithms. Promising and comparable results are obtained for most of the test problems. To improve the performance of SOPT, an improvement in the algorithm is proposed which helps it to come out of local optima when algorithm gets trapped in it. In almost all the test problems, improved SOPT is able to get the actual solution at least once in 30 runs.

  20. Improved Quantum-Inspired Evolutionary Algorithm for Engineering Design Optimization

    Directory of Open Access Journals (Sweden)

    Jinn-Tsong Tsai

    2012-01-01

    Full Text Available An improved quantum-inspired evolutionary algorithm is proposed for solving mixed discrete-continuous nonlinear problems in engineering design. The proposed Latin square quantum-inspired evolutionary algorithm (LSQEA combines Latin squares and quantum-inspired genetic algorithm (QGA. The novel contribution of the proposed LSQEA is the use of a QGA to explore the optimal feasible region in macrospace and the use of a systematic reasoning mechanism of the Latin square to exploit the better solution in microspace. By combining the advantages of exploration and exploitation, the LSQEA provides higher computational efficiency and robustness compared to QGA and real-coded GA when solving global numerical optimization problems with continuous variables. Additionally, the proposed LSQEA approach effectively solves mixed discrete-continuous nonlinear design optimization problems in which the design variables are integers, discrete values, and continuous values. The computational experiments show that the proposed LSQEA approach obtains better results compared to existing methods reported in the literature.

  1. Improved clipped periodic optimal control for semi-active harmonic disturbance rejection

    Science.gov (United States)

    Couillard, Maxime; Micheau, Philippe; Masson, Patrice

    2008-12-01

    This paper presents a new approach for harmonic disturbance rejection using semi-active vibration control. The approach is illustrated through application to the problem of maximizing the energy dissipated by a semi-active damper under harmonic excitation. In order to establish a baseline for the evaluation of the performance of the semi-active damper, the effectiveness of the optimal passive and active cases are first presented. The study then examines the ability of the clipped optimal control (or clipping control) approach to improve the energy dissipation capacity of the semi-active damper over the optimal passive damper. An approximate solution to the nonlinear dynamic problem, obtained using the method of averaging, and a time integration based numerical method indicate that this approach improves the energy dissipated by the semi-active damper over the optimal passive damper. The approach presented in this paper intends to further "improve", or "fine tune", the control parameters given by the clipped optimal control approach. This is done using an approximated solution of the problem and an appropriate optimization algorithm. Results clearly indicate that this new approach provides significant improvement on energy dissipation over the clipped optimal control approach for the semi-active damper.

  2. Optimized Clustering Estimators for BAO Measurements Accounting for Significant Redshift Uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Ashley J. [Portsmouth U., ICG; Banik, Nilanjan [Fermilab; Avila, Santiago [Madrid, IFT; Percival, Will J. [Portsmouth U., ICG; Dodelson, Scott [Fermilab; Garcia-Bellido, Juan [Madrid, IFT; Crocce, Martin [ICE, Bellaterra; Elvin-Poole, Jack [Jodrell Bank; Giannantonio, Tommaso [Cambridge U., KICC; Manera, Marc [Cambridge U., DAMTP; Sevilla-Noarbe, Ignacio [Madrid, CIEMAT

    2017-05-15

    We determine an optimized clustering statistic to be used for galaxy samples with significant redshift uncertainty, such as those that rely on photometric redshifts. To do so, we study the BAO information content as a function of the orientation of galaxy clustering modes with respect to their angle to the line-of-sight (LOS). The clustering along the LOS, as observed in a redshift-space with significant redshift uncertainty, has contributions from clustering modes with a range of orientations with respect to the true LOS. For redshift uncertainty $\\sigma_z \\geq 0.02(1+z)$ we find that while the BAO information is confined to transverse clustering modes in the true space, it is spread nearly evenly in the observed space. Thus, measuring clustering in terms of the projected separation (regardless of the LOS) is an efficient and nearly lossless compression of the signal for $\\sigma_z \\geq 0.02(1+z)$. For reduced redshift uncertainty, a more careful consideration is required. We then use more than 1700 realizations of galaxy simulations mimicking the Dark Energy Survey Year 1 sample to validate our analytic results and optimized analysis procedure. We find that using the correlation function binned in projected separation, we can achieve uncertainties that are within 10 per cent of of those predicted by Fisher matrix forecasts. We predict that DES Y1 should achieve a 5 per cent distance measurement using our optimized methods. We expect the results presented here to be important for any future BAO measurements made using photometric redshift data.

  3. Optimization of significant insolation distribution parameters - A new approach towards BIPV system design

    Energy Technology Data Exchange (ETDEWEB)

    Paul, D. [SSBB and Senior Member-ASQ, Kolkata (India); Mandal, S.N. [Kalyani Govt Engg College, Kalyani (India); Mukherjee, D.; Bhadra Chaudhuri, S.R. [Dept of E. and T. C. Engg, B.E.S.U., Shibpur (India)

    2010-10-15

    System efficiency and payback time are yet to attain a commercially viable level for solar photovoltaic energy projects. Despite huge development in prediction of solar radiation data, there is a gap in extraction of pertinent information from such data. Hence the available data cannot be effectively utilized for engineering application. This is acting as a barrier for the emerging technology. For making accurate engineering and financial calculations regarding any solar energy project, it is crucial to identify and optimize the most significant statistic(s) representing insolation availability by the Photovoltaic setup at the installation site. Quality Function Deployment (QFD) technique has been applied for identifying the statistic(s), which are of high significance from a project designer's point of view. A MATLAB trademark program has been used to build the annual frequency distribution of hourly insolation over any module plane at a given location. Descriptive statistical analysis of such distributions is done through MINITAB trademark. For Building Integrated Photo Voltaic (BIPV) installation, similar statistical analysis has been carried out for the composite frequency distribution, which is formed by weighted summation of insolation distributions for different module planes used in the installation. Vital most influential statistic(s) of the composite distribution have been optimized through Artificial Neural Network computation. This approach is expected to open up a new horizon in BIPV system design. (author)

  4. Optimal Formation Reconfiguration Control of Multiple UCAVs Using Improved Particle Swarm Optimization

    Institute of Scientific and Technical Information of China (English)

    Hai-bin Duan; Guan-jun Ma; De-lin Luo

    2008-01-01

    Optimal formation reconfiguration control of multiple Uninhabited Combat Air Vehicles (UCAVs) is a complicated global optimum problem. Particle Swarm Optimization (PSO) is a population based stochastic optimization technique inspired by social behaviour of bird flocking or fish schooling. PSO can achieve better results in a faster, cheaper way compared with other bio-inspired computational methods, and there are few parameters to adjust in PSO. In this paper, we propose an improved PSO model for solving the optimal formation reconfiguration control problem for multiple UCAVs. Firstly, the Control Parameteri-zation and Time Discretization (CPTD) method is designed in detail. Then, the mutation strategy and a special mutation-escape operator are adopted in the improved PSO model to make particles explore the search space more efficiently. The proposed strategy can produce a large speed value dynamically according to the variation of the speed, which makes the algorithm explore the local and global minima thoroughly at the same time. Series experimental results demonstrate the feasibility and effectiveness of the proposed method in solving the optimal formation reconfiguration control problem for multiple UCAVs.

  5. Optimizing strategies to improve interprofessional practice for veterans, part 1

    Directory of Open Access Journals (Sweden)

    Bhattacharya SB

    2014-04-01

    Full Text Available Shelley B Bhattacharya,1–3 Michelle I Rossi,1,2 Jennifer M Mentz11Geriatric Research Education and Clinical Center (GRECC, Veteran's Affairs Pittsburgh Healthcare System, 2University of Pittsburgh Medical Center, Pittsburgh, PA, USA; 3Albert Schweitzer Fellowship Program, Pittsburgh, PA, USAIntroduction: Interprofessional patient care is a well-recognized path that health care systems are striving toward. The Veteran's Affairs (VA system initiated interprofessional practice (IPP models with their Geriatric Evaluation and Management (GEM programs. GEM programs incorporate a range of specialties, including but not limited to, medicine, nursing, social work, physical therapy and pharmacy, to collaboratively evaluate veterans. Despite being a valuable resource, they are now faced with significant cut-backs, including closures. The primary goal of this project was to assess how the GEM model could be optimized at the Pittsburgh, Pennsylvania VA to allow for the sustainability of this important IPP assessment. Part 1 of the study evaluated the IPP process using program, patient, and family surveys. Part 2 examined how well the geriatrician matched patients to specialists in the GEM model. This paper describes Part 1 of our study.Methods: Three strategies were used: 1 a national GEM program survey; 2 a veteran/family satisfaction survey; and 3 an absentee assessment.Results: Twenty-six of 92 programs responded to the GEM IPP survey. Six strategies were shared to optimize IPP models throughout the country. Of the 34 satisfaction surveys, 80% stated the GEM clinic was beneficial, 79% stated their concerns were addressed, and 100% would recommend GEM to their friends. Of the 24 absentee assessments, the top three reasons for missing the appointments were transportation, medical illnesses, and not knowing/remembering about the appointment. Absentee rate diminished from 41% to 19% after instituting a reminder phone call policy.Discussion: Maintaining the

  6. Combinatorial optimization problem solution based on improved genetic algorithm

    Science.gov (United States)

    Zhang, Peng

    2017-08-01

    Traveling salesman problem (TSP) is a classic combinatorial optimization problem. It is a simplified form of many complex problems. In the process of study and research, it is understood that the parameters that affect the performance of genetic algorithm mainly include the quality of initial population, the population size, and crossover probability and mutation probability values. As a result, an improved genetic algorithm for solving TSP problems is put forward. The population is graded according to individual similarity, and different operations are performed to different levels of individuals. In addition, elitist retention strategy is adopted at each level, and the crossover operator and mutation operator are improved. Several experiments are designed to verify the feasibility of the algorithm. Through the experimental results analysis, it is proved that the improved algorithm can improve the accuracy and efficiency of the solution.

  7. Improving Data Transfer Throughput with Direct Search Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Balaprakash, Prasanna; Morozov, Vitali; Kettimuthu, Rajkumar; Kumaran, Kalyan; Foster, Ian

    2016-01-01

    Improving data transfer throughput over high-speed long-distance networks has become increasingly difficult. Numerous factors such as nondeterministic congestion, dynamics of the transfer protocol, and multiuser and multitask source and destination endpoints, as well as interactions among these factors, contribute to this difficulty. A promising approach to improving throughput consists in using parallel streams at the application layer.We formulate and solve the problem of choosing the number of such streams from a mathematical optimization perspective. We propose the use of direct search methods, a class of easy-to-implement and light-weight mathematical optimization algorithms, to improve the performance of data transfers by dynamically adapting the number of parallel streams in a manner that does not require domain expertise, instrumentation, analytical models, or historic data. We apply our method to transfers performed with the GridFTP protocol, and illustrate the effectiveness of the proposed algorithm when used within Globus, a state-of-the-art data transfer tool, on productionWAN links and servers. We show that when compared to user default settings our direct search methods can achieve up to 10x performance improvement under certain conditions. We also show that our method can overcome performance degradation due to external compute and network load on source end points, a common scenario at high performance computing facilities.

  8. Radiotherapy Planning Using an Improved Search Strategy in Particle Swarm Optimization

    Science.gov (United States)

    Modiri, Arezoo; Gu, Xuejun; Hagan, Aaron M.; Sawant, Amit

    2016-01-01

    Objective Evolutionary stochastic global optimization algorithms are widely used in large-scale, non-convex problems. However, enhancing the search efficiency and repeatability of these techniques often requires well-customized approaches. This study investigates one such approach. Methods We use particle swarm optimization (PSO) algorithm to solve a 4-dimensional radiation therapy (RT) inverse planning problem, where the key idea is to use respiratory motion as an additional degree of freedom in lung cancer RT. The primary goal is to administer a lethal dose to the tumor target while sparing surrounding healthy tissue. Our iteratively adjusts radiation fluence-weights for all beam apertures across all respiratory phases. We implement three PSO-based approaches: conventionally-used unconstrained, hard-constrained and our proposed virtual search. As proof of concept, five lung cancer patient cases are optimized over ten runs using each PSO approach. For comparison, a dynamically penalized likelihood (DPL) algorithm- a popular RT optimization technique is also implemented and used. Results The proposed technique significantly improves the robustness to random initialization while requiring fewer iteration cycles to converge across all cases. DPL manages to find the global optimum in 2 out of 5 RT cases over significantly more iterations. Conclusion The proposed virtual search approach boosts the swarm search efficiency and, consequently, improves the optimization convergence rate and robustness for PSO. Significance RT planning is a large-scale, non-convex optimization problem, where finding optimal solutions in a clinically practical time is critical. Our proposed approach can potentially improve the optimization efficiency in similar time-sensitive problems. PMID:27362755

  9. Improving time to optimal Staphylococcus aureus treatment using a penicillin-binding protein 2a assay.

    Science.gov (United States)

    Rao, Sonia N; Wang, Sheila K; Gonzalez Zamora, Jose; Hanson, Amy P; Polisetty, Radhika S; Singh, Kamaljit

    2016-12-01

    The penicillin-binding protein 2a (PBP2a) assay is a quick, accurate and inexpensive test for determining methicillin susceptibility in Staphylococcus aureus. A pre-post-study design was conducted using a PBP2a assay with and without the impact of an antimicrobial stewardship intervention to improve time to optimal therapy for methicillin-susceptible and methicillin-resistant S. aureus isolates. Our results demonstrate significantly improved time to optimal therapy and support the use of a PBP2a assay as part of an programme for all healthcare facilities, especially those with limited resources.

  10. Optimal design of pressure vessel using an improved genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    Peng-fei LIU; Ping XU; Shu-xin HAN; Jin-yang ZHENG

    2008-01-01

    As the idea of simulated annealing(SA) is introduced into the fitness function,an improved genetic algorithm(GA) is proposed to perform the optimal design of a pressure vessel which aims to attain the minimum weight under burst pressure constraint.The actual burst pressure is calculated using the arc-length and restart analysis in finite element analysis(FEA).A penalty function in the fitness function is proposed to denl with the constrained problem.The erects of the population size and the number of generations in the GA on the weight and burst pressure of the vessel are explored.The optimization results using the proposed GA are also compared with those using the simple GA and the conventional Monte Carlo method.

  11. Improved Sensitivity Relations in State Constrained Optimal Control

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, Piernicola, E-mail: piernicola.bettiol@univ-brest.fr [Université de Bretagne Occidentale, Laboratoire de Mathematiques (France); Frankowska, Hélène, E-mail: frankowska@math.jussieu.fr [Université Pierre et Marie Curie (Paris 6), CNRS and Institut de Mathématiques de Jussieu (France); Vinter, Richard B., E-mail: r.vinter@imperial.ac.uk [Imperial College London, Department of Electrical and Electronic Engineering (United Kingdom)

    2015-04-15

    Sensitivity relations in optimal control provide an interpretation of the costate trajectory and the Hamiltonian, evaluated along an optimal trajectory, in terms of gradients of the value function. While sensitivity relations are a straightforward consequence of standard transversality conditions for state constraint free optimal control problems formulated in terms of control-dependent differential equations with smooth data, their verification for problems with either pathwise state constraints, nonsmooth data, or for problems where the dynamic constraint takes the form of a differential inclusion, requires careful analysis. In this paper we establish validity of both ‘full’ and ‘partial’ sensitivity relations for an adjoint state of the maximum principle, for optimal control problems with pathwise state constraints, where the underlying control system is described by a differential inclusion. The partial sensitivity relation interprets the costate in terms of partial Clarke subgradients of the value function with respect to the state variable, while the full sensitivity relation interprets the couple, comprising the costate and Hamiltonian, as the Clarke subgradient of the value function with respect to both time and state variables. These relations are distinct because, for nonsmooth data, the partial Clarke subdifferential does not coincide with the projection of the (full) Clarke subdifferential on the relevant coordinate space. We show for the first time (even for problems without state constraints) that a costate trajectory can be chosen to satisfy the partial and full sensitivity relations simultaneously. The partial sensitivity relation in this paper is new for state constraint problems, while the full sensitivity relation improves on earlier results in the literature (for optimal control problems formulated in terms of Lipschitz continuous multifunctions), because a less restrictive inward pointing hypothesis is invoked in the proof, and because

  12. Chain alignment for improved properties - Optimization of PLA and PHB-V by crystallization and reinforcement

    Science.gov (United States)

    Moser, K.; Bergmann, B.; Diemert, J.; Elsner, P.

    2014-05-01

    In this paper two promising ways to improve the material characteristics of PLA and PHB-V are presented by showing their positive effects on mechanical, optical, and thermal properties. The optimization is achieved by increasing the crystallization from the melt of the polymer chains and the other by means of a reinforcement of the matrices by bio-based materials. In the case of crystallization specific nucleating agents and optimized process parameters promote optimized crystallization conditions and lead particularly in toughness to significant improvements. In addition to crystallization the introduction of cellulose-based reinforcing materials is also a good alternative to improve the ductility of a biopolymer matrix considerably. Due to their polar surface structure cellulose fibres are favouring a very good interaction to the also polar biopolymers. In addition, the polar surfaces of both materials results in very homogeneous dispersion within the compound.

  13. Optimization of temperature, sugar concentration, and inoculum size to maximize ethanol production without significant decrease in yeast cell viability.

    Science.gov (United States)

    Laluce, Cecilia; Tognolli, João Olimpio; de Oliveira, Karen Fernanda; Souza, Crisla Serra; Morais, Meline Rezende

    2009-06-01

    Aiming to obtain rapid fermentations with high ethanol yields and a retention of high final viabilities (responses), a 2(3) full-factorial central composite design combined with response surface methodology was employed using inoculum size, sucrose concentration, and temperature as independent variables. From this statistical treatment, two well-fitted regression equations having coefficients significant at the 5% level were obtained to predict the viability and ethanol production responses. Three-dimensional response surfaces showed that increasing temperatures had greater negative effects on viability than on ethanol production. Increasing sucrose concentrations improved both ethanol production and viability. The interactions between the inoculum size and the sucrose concentrations had no significant effect on viability. Thus, the lowering of the process temperature is recommended in order to minimize cell mortality and maintain high levels of ethanol production when the temperature is on the increase in the industrial reactor. Optimized conditions (200 g/l initial sucrose, 40 g/l of dry cell mass, 30 degrees C) were experimentally confirmed and the optimal responses are 80.8 +/- 2.0 g/l of maximal ethanol plus a viability retention of 99.0 +/- 3.0% for a 4-h fermentation period. During consecutive fermentations with cell reuse, the yeast cell viability has to be kept at a high level in order to prevent the collapse of the process.

  14. Optimization of Transient Heat Exchanger Performance for Improved Energy Efficiency

    Science.gov (United States)

    Bran Anleu, Gabriela; Kavehpour, Pirouz; Lavine, Adrienne; Wirz, Richard

    2014-11-01

    Heat exchangers are used in a multitude of applications within systems for energy generation, energy conversion, or energy storage. Many of these systems (e.g. solar power plants) function under transient conditions, but the design of the heat exchangers is typically optimized assuming steady state conditions. There is a potential for significant energy savings if the transient behavior of the heat exchanger is taken into account in designing the heat exchanger by optimizing its operating conditions in relation to the transient behavior of the overall system. The physics of the transient behavior of a heat exchanger needs to be understood to provide design parameters for transient heat exchangers to deliver energy savings. A numerical model was used to determine the optimized mass flow rates thermal properties for a thermal energy storage system. The transient behavior is strongly linked to the dimensionless parameters relating fluid properties, the mass flow rates, and the temperature of the fluids at the inlet of each stream. Smart metals, or advanced heat exchanger surface geometries and methods of construction will be used to meet the three goals mentioned before: 1) energy and cost reduction, 2) size reduction, and 3) optimal performance for all modes of operation.

  15. Improved Ant Colony Optimization for Seafood Product Delivery Routing Problem

    Directory of Open Access Journals (Sweden)

    Baozhen Yao

    2014-02-01

    Full Text Available This paper deals with a real-life vehicle delivery routing problem, which is a seafood product delivery routing problem. Considering the features of the seafood product delivery routing problem, this paper formulated this problem as a multi-depot open vehicle routing problem. Since the multi-depot open vehicle routing problem is a very complex problem, a method is used to reduce the complexity of the problem by changing the multi-depot open vehicle routing problem into an open vehicle routing problem with a dummy central depot in this paper. Then, ant colony optimization is used to solve the problem. To improve the performance of the algorithm, crossover operation and some adaptive strategies are used. Finally, the computational results for the benchmark problems of the multi-depot vehicle routing problem indicate that the proposed ant colony optimization is an effective method to solve the multi-depot vehicle routing problem. Furthermore, the computation results of the seafood product delivery problem from Dalian, China also suggest that the proposed ant colony optimization is feasible to solve the seafood product delivery routing problem.

  16. Analytical Tools to Improve Optimization Procedures for Lateral Flow Assays

    Directory of Open Access Journals (Sweden)

    Helen V. Hsieh

    2017-05-01

    Full Text Available Immunochromatographic or lateral flow assays (LFAs are inexpensive, easy to use, point-of-care medical diagnostic tests that are found in arenas ranging from a doctor’s office in Manhattan to a rural medical clinic in low resource settings. The simplicity in the LFA itself belies the complex task of optimization required to make the test sensitive, rapid and easy to use. Currently, the manufacturers develop LFAs by empirical optimization of material components (e.g., analytical membranes, conjugate pads and sample pads, biological reagents (e.g., antibodies, blocking reagents and buffers and the design of delivery geometry. In this paper, we will review conventional optimization and then focus on the latter and outline analytical tools, such as dynamic light scattering and optical biosensors, as well as methods, such as microfluidic flow design and mechanistic models. We are applying these tools to find non-obvious optima of lateral flow assays for improved sensitivity, specificity and manufacturing robustness.

  17. Economic Dispatch Thermal Generator Using Modified Improved Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    M. Natsir Rahman

    2012-07-01

    Full Text Available Fuel cost of a thermal generator is its own load functions. In this research, Modified Improved Particle Swarm Optimization (MIPSO is applied to calculate economic dispatch. Constriction Factor Approach (CFA is used to modify IPSO algorithm because of the advantage to improve the ability of global searching and avoid local minimum so that the time needed to converge become faster. Simulation results achieved by using  MIPSO method at the time of peak load of of 9602 MW, obtained generation cost is Rp 7,366,912,798,34 per hour, while generation cost of real system is Rp. 7,724,012,070.30 per hour. From the simulation result can be concluded that MIPSO can reduce the generation cost of  500 kV Jawa Bali transmission system of Rp 357,099,271.96 per hour or equal to 4,64%.

  18. Economic Dispatch Thermal Generator Using Modified Improved Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    M. Natsir Rahman

    2012-09-01

    Full Text Available Fuel cost of a thermal generator is its own load functions. In this research, Modified Improved Particle Swarm Optimization (MIPSO is applied to calculate economic dispatch. Constriction Factor Approach (CFA is used to modify IPSO algorithm because of the advantage to improve the ability of global searching and avoid local minimum so that the time needed to converge become faster. Simulation results achieved by using  MIPSO method at the time of peak load of of 9602 MW, obtained generation cost is Rp 7,366,912,798,34 per hour, while generation cost of real system is Rp. 7,724,012,070.30 per hour. From the simulation result can be concluded that MIPSO can reduce the generation cost of  500 kV Jawa Bali transmission system of Rp 357,099,271.96 per hour or equal to 4,64%.

  19. An improved model for TPV performance predictions and optimization

    Science.gov (United States)

    Schroeder, K. L.; Rose, M. F.; Burkhalter, J. E.

    1997-03-01

    Previously a model has been presented for calculating the performance of a TPV system. This model has been revised into a general purpose algorithm, improved in fidelity, and is presented here. The basic model is an energy based formulation and evaluates both the radiant and heat source elements of a combustion based system. Improvements in the radiant calculations include the use of ray tracking formulations and view factors for evaluating various flat plate and cylindrical configurations. Calculation of photocell temperature and performance parameters as a function of position and incident power have also been incorporated. Heat source calculations have been fully integrated into the code by the incorporation of a modified version of the NASA Complex Chemical Equilibrium Compositions and Applications (CEA) code. Additionally, coding has been incorporated to allow optimization of various system parameters and configurations. Several examples cases are presented and compared, and an optimum flat plate emitter/filter/photovoltaic configuration is also described.

  20. Improved Rao-Blackwellized Particle Filter by Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Zeng-Shun Zhao

    2013-01-01

    Full Text Available The Rao-Blackwellized particle filter (RBPF algorithm usually has better performance than the traditional particle filter (PF by utilizing conditional dependency relationships between parts of the state variables to estimate. By doing so, RBPF could not only improve the estimation precision but also reduce the overall computational complexity. However, the computational burden is still too high for many real-time applications. To improve the efficiency of RBPF, the particle swarm optimization (PSO is applied to drive all the particles to the regions where their likelihoods are high in the nonlinear area. So only a small number of particles are needed to participate in the required computation. The experimental results demonstrate that this novel algorithm is more efficient than the standard RBPF.

  1. Improving IMRT-plan quality with MLC leaf position refinement post plan optimization.

    Science.gov (United States)

    Niu, Ying; Zhang, Guowei; Berman, Barry L; Parke, William C; Yi, Byongyong; Yu, Cedric X

    2012-08-01

    In intensity-modulated radiation therapy (IMRT) planning, reducing the pencil-beam size may lead to a significant improvement in dose conformity, but also increase the time needed for the dose calculation and plan optimization. The authors develop and evaluate a postoptimization refinement (POpR) method, which makes fine adjustments to the multileaf collimator (MLC) leaf positions after plan optimization, enhancing the spatial precision and improving the plan quality without a significant impact on the computational burden. The authors' POpR method is implemented using a commercial treatment planning system based on direct aperture optimization. After an IMRT plan is optimized using pencil beams with regular pencil-beam step size, a greedy search is conducted by looping through all of the involved MLC leaves to see if moving the MLC leaf in or out by half of a pencil-beam step size will improve the objective function value. The half-sized pencil beams, which are used for updating dose distribution in the greedy search, are derived from the existing full-sized pencil beams without need for further pencil-beam dose calculations. A benchmark phantom case and a head-and-neck (HN) case are studied for testing the authors' POpR method. Using a benchmark phantom and a HN case, the authors have verified that their POpR method can be an efficient technique in the IMRT planning process. Effectiveness of POpR is confirmed by noting significant improvements in objective function values. Dosimetric benefits of POpR are comparable to those of using a finer pencil-beam size from the optimization start, but with far less computation and time. The POpR is a feasible and practical method to significantly improve IMRT-plan quality without compromising the planning efficiency.

  2. An Improved Quantum-Behaved Particle Swarm Optimization Algorithm with Elitist Breeding for Unconstrained Optimization

    Directory of Open Access Journals (Sweden)

    Zhen-Lun Yang

    2015-01-01

    Full Text Available An improved quantum-behaved particle swarm optimization with elitist breeding (EB-QPSO for unconstrained optimization is presented and empirically studied in this paper. In EB-QPSO, the novel elitist breeding strategy acts on the elitists of the swarm to escape from the likely local optima and guide the swarm to perform more efficient search. During the iterative optimization process of EB-QPSO, when criteria met, the personal best of each particle and the global best of the swarm are used to generate new diverse individuals through the transposon operators. The new generated individuals with better fitness are selected to be the new personal best particles and global best particle to guide the swarm for further solution exploration. A comprehensive simulation study is conducted on a set of twelve benchmark functions. Compared with five state-of-the-art quantum-behaved particle swarm optimization algorithms, the proposed EB-QPSO performs more competitively in all of the benchmark functions in terms of better global search capability and faster convergence rate.

  3. An Improved Quantum-Behaved Particle Swarm Optimization Algorithm with Elitist Breeding for Unconstrained Optimization.

    Science.gov (United States)

    Yang, Zhen-Lun; Wu, Angus; Min, Hua-Qing

    2015-01-01

    An improved quantum-behaved particle swarm optimization with elitist breeding (EB-QPSO) for unconstrained optimization is presented and empirically studied in this paper. In EB-QPSO, the novel elitist breeding strategy acts on the elitists of the swarm to escape from the likely local optima and guide the swarm to perform more efficient search. During the iterative optimization process of EB-QPSO, when criteria met, the personal best of each particle and the global best of the swarm are used to generate new diverse individuals through the transposon operators. The new generated individuals with better fitness are selected to be the new personal best particles and global best particle to guide the swarm for further solution exploration. A comprehensive simulation study is conducted on a set of twelve benchmark functions. Compared with five state-of-the-art quantum-behaved particle swarm optimization algorithms, the proposed EB-QPSO performs more competitively in all of the benchmark functions in terms of better global search capability and faster convergence rate.

  4. Improving the performance of DCT-based fragile watermarking using intelligent optimization algorithms

    Science.gov (United States)

    Aslantas, Veysel; Ozer, Saban; Ozturk, Serkan

    2009-07-01

    The performance of a fragile watermarking method based on discrete cosine transform (DCT) has been improved in this paper by using intelligent optimization algorithms (IOA), namely genetic algorithm, differential evolution algorithm, clonal selection algorithm and particle swarm optimization algorithm. In DCT based fragile watermarking techniques, watermark embedding can usually be achieved by modifying the least significant bits of the transformation coefficients. After the embedding process is completed, transforming the modified coefficients from the frequency domain to the spatial domain produces some rounding errors due to the conversion of real numbers to integers. The rounding errors caused by this transformation process were corrected by the use of intelligent optimization algorithms mentioned above. This paper gives experimental results which show the feasibility of using these optimization algorithms for the fragile watermarking and demonstrate the accuracy of these methods. The performance comparison of the algorithms was also realized.

  5. An Improved Teaching-Learning-Based Optimization with the Social Character of PSO for Global Optimization

    Directory of Open Access Journals (Sweden)

    Feng Zou

    2016-01-01

    Full Text Available An improved teaching-learning-based optimization with combining of the social character of PSO (TLBO-PSO, which is considering the teacher’s behavior influence on the students and the mean grade of the class, is proposed in the paper to find the global solutions of function optimization problems. In this method, the teacher phase of TLBO is modified; the new position of the individual is determined by the old position, the mean position, and the best position of current generation. The method overcomes disadvantage that the evolution of the original TLBO might stop when the mean position of students equals the position of the teacher. To decrease the computation cost of the algorithm, the process of removing the duplicate individual in original TLBO is not adopted in the improved algorithm. Moreover, the probability of local convergence of the improved method is decreased by the mutation operator. The effectiveness of the proposed method is tested on some benchmark functions, and the results are competitive with respect to some other methods.

  6. Improving the Dynamic Characteristics of Body-in-White Structure Using Structural Optimization

    Directory of Open Access Journals (Sweden)

    Aizzat S. Yahaya Rashid

    2014-01-01

    Full Text Available The dynamic behavior of a body-in-white (BIW structure has significant influence on the noise, vibration, and harshness (NVH and crashworthiness of a car. Therefore, by improving the dynamic characteristics of BIW, problems and failures associated with resonance and fatigue can be prevented. The design objectives attempt to improve the existing torsion and bending modes by using structural optimization subjected to dynamic load without compromising other factors such as mass and stiffness of the structure. The natural frequency of the design was modified by identifying and reinforcing the structure at critical locations. These crucial points are first identified by topology optimization using mass and natural frequencies as the design variables. The individual components obtained from the analysis go through a size optimization step to find their target thickness of the structure. The thickness of affected regions of the components will be modified according to the analysis. The results of both optimization steps suggest several design modifications to achieve the target vibration specifications without compromising the stiffness of the structure. A method of combining both optimization approaches is proposed to improve the design modification process.

  7. Power plant maintenance scheduling using ant colony optimization: an improved formulation

    Science.gov (United States)

    Foong, Wai Kuan; Maier, Holger; Simpson, Angus

    2008-04-01

    It is common practice in the hydropower industry to either shorten the maintenance duration or to postpone maintenance tasks in a hydropower system when there is expected unserved energy based on current water storage levels and forecast storage inflows. It is therefore essential that a maintenance scheduling optimizer can incorporate the options of shortening the maintenance duration and/or deferring maintenance tasks in the search for practical maintenance schedules. In this article, an improved ant colony optimization-power plant maintenance scheduling optimization (ACO-PPMSO) formulation that considers such options in the optimization process is introduced. As a result, both the optimum commencement time and the optimum outage duration are determined for each of the maintenance tasks that need to be scheduled. In addition, a local search strategy is presented in this article to boost the robustness of the algorithm. When tested on a five-station hydropower system problem, the improved formulation is shown to be capable of allowing shortening of maintenance duration in the event of expected demand shortfalls. In addition, the new local search strategy is also shown to have significantly improved the optimization ability of the ACO-PPMSO algorithm.

  8. Using the Significant Learning Taxonomy and Active Learning to Improve Accounting Education

    Science.gov (United States)

    Killian, Larita J.; Brandon, Christopher D.

    2009-01-01

    Like other members of the academy, accounting professors are challenged to improve student learning. We must help students move beyond the "bean counter" role and develop higher-level skills such as analysis, synthesis, and problem-solving. The Significant Learning Taxonomy was used as a template to improve learning in an introductory accounting…

  9. Recent improvements to software used for optimization of SRF linacs

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Tom J. [JLAB

    2014-12-01

    This work describes a software tool that allows one to vary parameters and understand the effects on the optimized costs of construction plus 10 year operations of an SRF linac, where operation costs includes the cost of the electrical utilities but not the labor or other costs. The program includes estimates for the associated cryogenic facility, and controls hardware. The software interface provides the ability to vary the cost of the different aspects of the machine as well as to change the cryomodule and cavity types. Additionally, this work will describe the recent improvements to the software that allow one to estimate the costs of energy-recovery based linacs and to enter arbitrary values of the low field Q0 and Q0 slope. The initial goal when developing the software was to convert a spreadsheet format to a graphical interface and to allow the ability to sweep different parameter sets. The tools also allow one to compare the cost of the different facets of the machine design and operations so as to better understand tradeoffs. An example of how it was used to independently investigate cost optimization tradeoffs for the LCLS-II linac will also be presented.

  10. Efficiency Improvements of Antenna Optimization Using Orthogonal Fractional Experiments

    Directory of Open Access Journals (Sweden)

    Yen-Sheng Chen

    2015-01-01

    Full Text Available This paper presents an extremely efficient method for antenna design and optimization. Traditionally, antenna optimization relies on nature-inspired heuristic algorithms, which are time-consuming due to their blind-search nature. In contrast, design of experiments (DOE uses a completely different framework from heuristic algorithms, reducing the design cycle by formulating the surrogates of a design problem. However, the number of required simulations grows exponentially if a full factorial design is used. In this paper, a much more efficient technique is presented to achieve substantial time savings. By using orthogonal fractional experiments, only a small subset of the full factorial design is required, yet the resultant response surface models are still effective. The capability of orthogonal fractional experiments is demonstrated through three examples, including two tag antennas for radio-frequency identification (RFID applications and one internal antenna for long-term-evolution (LTE handheld devices. In these examples, orthogonal fractional experiments greatly improve the efficiency of DOE, thereby facilitating the antenna design with less simulation runs.

  11. Dendritic Immunotherapy Improvement for an Optimal Control Murine Model

    Directory of Open Access Journals (Sweden)

    J. C. Rangel-Reyes

    2017-01-01

    Full Text Available Therapeutic protocols in immunotherapy are usually proposed following the intuition and experience of the therapist. In order to deduce such protocols mathematical modeling, optimal control and simulations are used instead of the therapist’s experience. Clinical efficacy of dendritic cell (DC vaccines to cancer treatment is still unclear, since dendritic cells face several obstacles in the host environment, such as immunosuppression and poor transference to the lymph nodes reducing the vaccine effect. In view of that, we have created a mathematical murine model to measure the effects of dendritic cell injections admitting such obstacles. In addition, the model considers a therapy given by bolus injections of small duration as opposed to a continual dose. Doses timing defines the therapeutic protocols, which in turn are improved to minimize the tumor mass by an optimal control algorithm. We intend to supplement therapist’s experience and intuition in the protocol’s implementation. Experimental results made on mice infected with melanoma with and without therapy agree with the model. It is shown that the dendritic cells’ percentage that manages to reach the lymph nodes has a crucial impact on the therapy outcome. This suggests that efforts in finding better methods to deliver DC vaccines should be pursued.

  12. Significantly enhancing recombinant alkaline amylase production in Bacillus subtilis by integration of a novel mutagenesis-screening strategy with systems-level fermentation optimization

    OpenAIRE

    2016-01-01

    Background Alkaline amylase has significant potential for applications in the textile, paper and detergent industries, however, low yield of which cannot meet the requirement of industrial application. In this work, a novel ARTP mutagenesis-screening method and fermentation optimization strategies were used to significantly improve the expression level of recombinant alkaline amylase in B. subtilis 168. Results The activity of alkaline amylase in mutant B. subtilis 168 mut-16# strain was 1.34...

  13. Speed control of optimal designed PMBLDC motor using improved fuzzy particle swarm optimization

    Directory of Open Access Journals (Sweden)

    Reza Saravani

    2014-09-01

    Full Text Available Permanent brushless dc motors have been used in many areas. Considering to their vast advantages, researchers have studied extensively for speed control and reducing the torque ripple of this motors. But a little study was done for both speed control and optimum design of them. This paper presents for the optimal design of a PMBLDC motor with goal of reducing volume and building cost. In addition the speed control aim is considered using a multi-objective nonlinear cost function which is solved by fuzzy particle swarm optimization. First characteristics of motor are expressed as functions of motor geometries. Then cost function which combines the step response characteristic of motor speed, building cost and its volume is constructed and minimized. To reach this goal in this application the new improved fuzzy particle swam optimization is used for the first time. The results of simulations show that this method has good ability and efficiency in reaching global best point in compare of GA and PSO methods.

  14. Engineering an improved acellular nerve graft via optimized chemical processing.

    Science.gov (United States)

    Hudson, Terry W; Liu, Stephen Y; Schmidt, Christine E

    2004-01-01

    The long-term goal of our research is to engineer an acellular nerve graft for clinical nerve repair and for use as a model system with which to study nerve-extracellular matrix interactions during nerve regeneration. To develop this model acellular nerve graft we (1) examined the effects of detergents on peripheral nerve tissue, and (2) used that knowledge to create a nerve graft devoid of cells with a well-preserved extracellular matrix. Using histochemistry and Western analysis, the impact of each detergent on cellular and extracellular tissue components was determined. An optimized protocol was created with the detergents Triton X-200, sulfobetaine-16, and sulfobetaine-10. This study represents the most comprehensive examination to date of the effects of detergents on peripheral nerve tissue morphology and protein composition. Also presented is an improved chemical decellularization protocol that preserves the internal structure of native nerve more than the predominant current protocol.

  15. Difficulties in Evolutionary Multiobjective Optimization for Many-Objective Optimization Problems and Their Scalability Improvement Techniques

    Science.gov (United States)

    Tsukamoto, Noritaka; Nojima, Yusuke; Ishibuchi, Hisao

    In this paper, we examine the behavior of evolutionary multiobjective optimization (EMO) algorithms to clarify the difficulties in their scalability to many-objective optimization problems. Whereas EMO algorithms usually work well on two-objective problems, it has also been reported that they do not work well on many-objective problems. First, we examine the behavior of the most well-known and frequently-used Pareto-based EMO algorithm (i. e. , NSGA-II) on many-objective 0/1 knapsack problems. Experimental results show that the search ability of NSGA-II is severely deteriorated by the increase in the number of objectives. This is because the selection pressure toward the Pareto front is severely weakened by the increase in the number of non-dominated solutions. Next we briefly review some approaches to the scalability improvement of EMO algorithms to many-objective problems. Then we examine their effects on the search ability of NSGA-II. Experimental results show that the improvement in the convergence of solutions to the Pareto front often leads to the decrease in their diversity.

  16. Optimized passive sonar placement to allow improved interdiction

    Science.gov (United States)

    Johnson, Bruce A.; Matthews, Cameron

    2016-05-01

    The Art Gallery Problem (AGP) is the name given to a constrained optimization problem meant to determine the maximum amount of sensor coverage while utilizing the minimum number of resources. The AGP is significant because a common issue among surveillance and interdiction systems is obtaining an understanding of the optimal position of sensors and weapons in advance of enemy combatant maneuvers. The implication that an optimal position for a sensor to observe an event or for a weapon to engage a target autonomously is usually very clear after the target has passed, but for autonomous systems the solution must at least be conjectured in advance for deployment purposes. This abstract applies the AGP as a means to solve where best to place underwater sensor nodes such that the amount of information acquired about a covered area is maximized while the number of resources used to gain that information is minimized. By phrasing the ISR/interdiction problem this way, the issue is addressed as an instance of the AGP. The AGP is a member of a set of computational problems designated as nondeterministic polynomial-time (NP)-hard. As a member of this set, the AGP shares its members' defining feature, namely that no one has proven that there exists a deterministic algorithm providing a computationally-tractable solution to the AGP within a finite amount of time. At best an algorithm meant to solve the AGP can asymptotically approach perfect coverage with minimal resource usage but providing perfect coverage would either break the minimal resource usage constraint or require an exponentially-growing amount of time. No perfectly-optimal solution yet exists to the AGP, however, approximately optimal solutions to the AGP can approach complete area or barrier coverage while simultaneously minimizing the number of sensors and weapons utilized. A minimal number of underwater sensor nodes deployed can greatly increase the Mean Time Between Operational Failure (MTBOF) and logistical

  17. Mutagenesis breeding of high echinocandin B producing strain and further titer improvement with culture medium optimization.

    Science.gov (United States)

    Zou, Shu-Ping; Zhong, Wei; Xia, Chao-Jie; Gu, Ya-Nan; Niu, Kun; Zheng, Yu-Guo; Shen, Yin-Chu

    2015-10-01

    A combination of microbial strain improvement and statistical optimization is investigated to maximize echinocandin B (ECB) production from Aspergillus nidulans ZJB-0817. A classical sequential mutagenesis was studied first by using physical (ultraviolet irradiation at 254 nm) and chemical mutagens (lithium chloride and sodium nitrite). Mutant strain ULN-59 exhibited 2.1-fold increase in ECB production to 1583.1 ± 40.9 mg/L when compared with the parent strain (750.8 ± 32.0 mg/L). This is the first report where mutagenesis is applied in Aspergillus to improve ECB production. Further, fractional factorial design and central composite design were adopted to optimize the culture medium for increasing ECB production by the mutant ULN-59. Results indicated that four culture media including peptone, K2HPO4, mannitol and L-ornithine had significant effects on ECB production. The optimized medium provided another 1.4-fold increase in final ECB concentration to 2285.6 ± 35.6 mg/L compared to the original medium. The results of this study indicated the combined application of a classical mutation and medium optimization can improve effectively ECB production from A. nidulans and could be a promising tool to improve other secondary metabolites production by fungal strains.

  18. Power optimization and performance improvement for embedded Ethernet SOC

    Institute of Scientific and Technical Information of China (English)

    ZHENG Zhao-xia; ZOU Lian-ying; GAO Jun

    2008-01-01

    Information appliance is the combination of traditional home appliances and the internet technology. In this article, an Ethernet controller system-on-chip (SOC) solution for information appliances is presented. To achieve high performance, the embedded 8 bits 8051 micro control unit (MCU) is optimized by an independent instruction bus and a data bus. Besides, a two-stage pipeline feature is added. Compared with the existing 8051 core, the enhanced one-cycle MCU offers ten times improvement in instruction execution efficiency. Mean- while, the performance of media access control (MAC) circuit is greatly improved by adopting various techniques such as direct memory access (DMA) control, paging strategy, etc. To reduce the power consumption, clock gating, low power supply, and multi-working-clock are adopted. Moreover, to achieve rapid data communication in different clock frequency circuits, a simple ping-pong first in first out (FIFO) circuit is realized. The chip is implemented using TSMC 0.25 μm two-poly four-metal mixed signal complementary metal oxide semiconductor (CMOS) technology. Its die area is mm. The test results show that the maximum throughput of Ethernet packets can reach 7 Mb/s while the power consumption is rather low-the working current is just about 200 mA.

  19. Improved Aerodynamic Analysis for Hybrid Wing Body Conceptual Design Optimization

    Science.gov (United States)

    Gern, Frank H.

    2012-01-01

    This paper provides an overview of ongoing efforts to develop, evaluate, and validate different tools for improved aerodynamic modeling and systems analysis of Hybrid Wing Body (HWB) aircraft configurations. Results are being presented for the evaluation of different aerodynamic tools including panel methods, enhanced panel methods with viscous drag prediction, and computational fluid dynamics. Emphasis is placed on proper prediction of aerodynamic loads for structural sizing as well as viscous drag prediction to develop drag polars for HWB conceptual design optimization. Data from transonic wind tunnel tests at the Arnold Engineering Development Center s 16-Foot Transonic Tunnel was used as a reference data set in order to evaluate the accuracy of the aerodynamic tools. Triangularized surface data and Vehicle Sketch Pad (VSP) models of an X-48B 2% scale wind tunnel model were used to generate input and model files for the different analysis tools. In support of ongoing HWB scaling studies within the NASA Environmentally Responsible Aviation (ERA) program, an improved finite element based structural analysis and weight estimation tool for HWB center bodies is currently under development. Aerodynamic results from these analyses are used to provide additional aerodynamic validation data.

  20. Optimization Controller for Mechatronic Sun Tracking System to Improve Performance

    Directory of Open Access Journals (Sweden)

    Mustafa Engin

    2013-01-01

    Full Text Available An embedded system that contains hardware and software was developed for two-axis solar tracking system to improve photovoltaic panel utilization. The hardware section of the embedded system consists of a 32-bit ARM core microcontroller, motor driver circuits, a motion control unit, pyranometer, GPS receiver, and an anemometer. The real-time control algorithm enables the solar tracker to operate automatically without external control as a stand-alone system, combining the advantages of the open-loop and the closed-loop control methods. The pyranometer is employed to continuously send radiation data to the controller if the measured radiation is above the lower radiation limit the photovoltaic panel can generate power, guaranteeing the solar tracking process to be highly efficient. The anemometer is utilized in the system to ensure that the solar tracking procedure halts under high wind speed conditions to protect the entire system. Latitude, longitude, altitude, date, and real-time clock data are provided by GPS receiver. The algorithm calculates solar time using astronomical equations with GPS data and converts it to pulse-width modulated motor control signal. The overall objective of this study is to develop a control algorithm that improves performance and reliability of the two-axis solar tracker, focusing on optimization of the controller board, drive hardware, and software.

  1. Recent developments in KTF. Code optimization and improved numerics

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Javier; Avramova, Maria; Sanchez, Victor Hugo; Ivanov, Kostadin [Karlsruhe Institute of Technology (KIT) (Germany). Inst. for Neutron Physics and Reactor Technology (INR)

    2012-11-01

    The rapid increase of computer power in the last decade facilitated the development of high fidelity simulations in nuclear engineering allowing a more realistic and accurate optimization as well as safety assessment of reactor cores and power plants compared to the legacy codes. Thermal hydraulic subchannel codes together with time dependent neutron transport codes are the options of choice for an accurate prediction of local safety parameters. Moreover, fast running codes with the best physical models are needed for high fidelity coupled thermal hydraulic / neutron kinetic solutions. Hence at KIT, different subchannel codes such as SUBCHANFLOW and KTF are being improved, validated and coupled with different neutron kinetics solutions. KTF is a subchannel code developed for best-estimate analysis of both Pressurized Water Reactor (PWR) and BWR. It is based on the Pennsylvania State University (PSU) version of COBRA-TF (Coolant Boling in Rod Arrays Two Fluids) named CTF. In this paper, the investigations devoted to the enhancement of the code numeric and informatics structure are presented and discussed. By some examples the gain on code speed-up will be demonstrated and finally an outlook of further activities concentrated on the code improvements will be given. (orig.)

  2. The significance of crop co-states for receding horizon optimal control of greenhouse climate

    NARCIS (Netherlands)

    Straten, van G.; Willigenburg, van L.G.; Tap, R.F.

    2002-01-01

    While a tomato crop grows on the time-scale of weeks, the greenhouse climate changes on a time-scale of minutes. The economic optimal control problem of producing good quality crops against minimum input of resources is tackled by a two time-scale decomposition. First, the sub-problem associated to

  3. Parameter definition using vibration prediction software leads to significant drilling performance improvements

    Energy Technology Data Exchange (ETDEWEB)

    Amorim, Dalmo; Hanley, Chris Hanley; Fonseca, Isaac; Santos, Juliana [National Oilwell Varco, Houston TX (United States); Leite, Daltro J.; Borella, Augusto; Gozzi, Danilo [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    field monitoring. Vibration prediction diminishes the importance of trial-and-error procedures such as drill-off tests, which are valid only for short sections. It also solves an existing lapse in Mechanical Specific Energy (MSE) real-time drilling control programs applying the theory of Teale, which states that a drilling system is perfectly efficient when it spends the exact energy to overcome the in situ rock strength. Using the proprietary software tool this paper will examine the resonant vibration modes that may be initiated while drilling with different BHA's and drill string designs, showing that the combination of a proper BHA design along with the correct selection of input parameters results in an overall improvement to drilling efficiency. Also, being the BHA predictively analyzed, it will be reduced the potential for vibration or stress fatigue in the drill string components, leading to a safer operation. In the recent years there has been an increased focus on vibration detection, analysis, and mitigation techniques, where new technologies, like the Drilling Dynamics Data Recorders (DDDR), may provide the capability to capture high frequency dynamics data at multiple points along the drilling system. These tools allow the achievement of drilling performance improvements not possible before, opening a whole new array of opportunities for optimization and for verification of predictions calculated by the drill string dynamics modeling software tool. The results of this study will identify how the dynamics from the drilling system, interacting with formation, directly relate to inefficiencies and to the possible solutions to mitigate drilling vibrations in order to improve drilling performance. Software vibration prediction and downhole measurements can be used for non-drilling operations like drilling out casing or reaming, where extremely high vibration levels - devastating to the cutting structure of the bit before it has even touched bottom - have

  4. Improved self-protection using dynamically optimized expendable countermeasures

    Science.gov (United States)

    Hovland, Harald

    2007-04-01

    The use of expendable countermeasures is still found to be a viable choice for self protection against Man Portable Air Defense Systems (MANPADS) due to their simplicity, low cost, flexibility, recent improvements in decoy technology, the ability to handle multiple threats simultaneously and the off-board nature of these countermeasures. In civil aviation, the risk of general hazards linked to the use of pyrotechnics is the main argument against expendable countermeasures, whereas for military platforms, the limitation in capacity due to a limited number of rounds is often used as an argument to replace expendable countermeasures by laser-based countermeasures. This latter argument is in general not substantiated by modelling or figures of merit, although it is often argued that a laser based system allows for more false alarms, hence enabling a more sensitive missile approach warning system. The author has developed a model that accounts for the statistical effects of running out of expendable countermeasures during a mission, in terms of the overall mission survival probability. The model includes key parameters of the missile approach warning system (MAWS), and can handle multiple missile types and missile attack configurations, as well as various statistical models of missile attacks. The model enables quantitative comparison between laser based and expendable countermeasures, but also a dynamic optimization of the countermeasures in terms of whether to use small or large countermeasure programs, as well as the dynamic tuning of MAWS key parameters to optimize the overall performance. The model is also well suited for determination of the contributions of the different components of the system in the overall survival probability.

  5. An improved Harmony Search algorithm for optimal scheduling of the diesel generators in oil rig platforms

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Parikshit; Kumar, Rajesh; Panda, S.K.; Chang, C.S. [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore)

    2011-02-15

    Harmony Search (HS) algorithm is music based meta-heuristic optimization method which is analogous with the music improvisation process where musician continue to polish the pitches in order to obtain better harmony. The paper focuses on the optimal scheduling of the generators to reduce the fuel consumption in the oil rig platform. The accurate modeling of the specific fuel consumption is significant in this optimization. The specific fuel consumption has been modeled using cubic spline interpolation. The SFC curve is non-linear and discrete in nature, hence conventional methods fail to give optimal solution. HS algorithm has been used for optimal scheduling of the generators of both equal and unequal rating. Furthermore an Improved Harmony Search (IHS) method for generating new solution vectors that enhances accuracy and convergence rate of HS has been employed. The paper also focuses on the impacts of constant parameters on Harmony Search algorithm. Numerical results show that the IHS method has good convergence property. Moreover, the fuel consumption for IHS algorithm is lower when compared to HS and other heuristic or deterministic methods and is a powerful search algorithm for various engineering optimization problems. (author)

  6. An improved ant colony optimization approach for optimization of process planning.

    Science.gov (United States)

    Wang, JinFeng; Fan, XiaoLiang; Ding, Haimin

    2014-01-01

    Computer-aided process planning (CAPP) is an important interface between computer-aided design (CAD) and computer-aided manufacturing (CAM) in computer-integrated manufacturing environments (CIMs). In this paper, process planning problem is described based on a weighted graph, and an ant colony optimization (ACO) approach is improved to deal with it effectively. The weighted graph consists of nodes, directed arcs, and undirected arcs, which denote operations, precedence constraints among operation, and the possible visited path among operations, respectively. Ant colony goes through the necessary nodes on the graph to achieve the optimal solution with the objective of minimizing total production costs (TPCs). A pheromone updating strategy proposed in this paper is incorporated in the standard ACO, which includes Global Update Rule and Local Update Rule. A simple method by controlling the repeated number of the same process plans is designed to avoid the local convergence. A case has been carried out to study the influence of various parameters of ACO on the system performance. Extensive comparative experiments have been carried out to validate the feasibility and efficiency of the proposed approach.

  7. Improved Reliability-Based Optimization with Support Vector Machines and Its Application in Aircraft Wing Design

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2015-01-01

    Full Text Available A new reliability-based design optimization (RBDO method based on support vector machines (SVM and the Most Probable Point (MPP is proposed in this work. SVM is used to create a surrogate model of the limit-state function at the MPP with the gradient information in the reliability analysis. This guarantees that the surrogate model not only passes through the MPP but also is tangent to the limit-state function at the MPP. Then, importance sampling (IS is used to calculate the probability of failure based on the surrogate model. This treatment significantly improves the accuracy of reliability analysis. For RBDO, the Sequential Optimization and Reliability Assessment (SORA is employed as well, which decouples deterministic optimization from the reliability analysis. The improved SVM-based reliability analysis is used to amend the error from linear approximation for limit-state function in SORA. A mathematical example and a simplified aircraft wing design demonstrate that the improved SVM-based reliability analysis is more accurate than FORM and needs less training points than the Monte Carlo simulation and that the proposed optimization strategy is efficient.

  8. Improving hardness of electroless Ni-B coatings using optimized deposition conditions and annealing

    Energy Technology Data Exchange (ETDEWEB)

    Oraon, B. [Department of Mechanical Engineering, Jadavpur University, Kolkata 700 032 (India)], E-mail: b_oraon_65@yahoo.co.in; Majumdar, G. [Department of Mechanical Engineering, Jadavpur University, Kolkata 700 032 (India); Ghosh, B. [Advanced Materials and Solar Photovoltaic Division, School of Energy Studies, Jadavpur University, Kolkata 700 032 (India)

    2008-07-01

    The alkaline borohydride-reduced bath has been used to deposit electroless nickel-boron (Ni-B) coatings on a pure (99.99%) copper substrate. The hardness of the Ni-B coatings has been improved using optimized deposition conditions and thereafter by annealing. The electroless Ni-B deposition per unit area has been considered as the response variable and response surface method (RSM) has been used to optimize the process parameters and the deposition per unit area. The electroless Ni-B coatings have again been formed at the optimized deposition conditions and the as-deposited coating hardness has been evaluated using an empirical model and regression analysis. It has been observed that there is a significant improvement in as-deposited coating hardness. The Ni-B coated specimens formed at optimized deposition conditions have also been annealed at different temperatures ranging from 100 deg. C to 500 deg. C. The hardness of the annealed specimens has been estimated for different annealing temperatures and has been observed that the coating hardness increases with annealing temperature and then further increase in annealing temperature reduces the coating hardness. The coating hardness becomes the highest for annealing temperature of about 300 deg. C. Both the as-deposited and annealed coating hardness have been observed to be significantly higher than that reported by many researchers for electroless Ni-B coatings.

  9. Application of Genetic Algorithm and Particle Swarm Optimization techniques for improved image steganography systems

    Directory of Open Access Journals (Sweden)

    Jude Hemanth Duraisamy

    2016-01-01

    Full Text Available Image steganography is one of the ever growing computational approaches which has found its application in many fields. The frequency domain techniques are highly preferred for image steganography applications. However, there are significant drawbacks associated with these techniques. In transform based approaches, the secret data is embedded in random manner in the transform coefficients of the cover image. These transform coefficients may not be optimal in terms of the stego image quality and embedding capacity. In this work, the application of Genetic Algorithm (GA and Particle Swarm Optimization (PSO have been explored in the context of determining the optimal coefficients in these transforms. Frequency domain transforms such as Bandelet Transform (BT and Finite Ridgelet Transform (FRIT are used in combination with GA and PSO to improve the efficiency of the image steganography system.

  10. Application of Genetic Algorithm and Particle Swarm Optimization techniques for improved image steganography systems

    Science.gov (United States)

    Jude Hemanth, Duraisamy; Umamaheswari, Subramaniyan; Popescu, Daniela Elena; Naaji, Antoanela

    2016-01-01

    Image steganography is one of the ever growing computational approaches which has found its application in many fields. The frequency domain techniques are highly preferred for image steganography applications. However, there are significant drawbacks associated with these techniques. In transform based approaches, the secret data is embedded in random manner in the transform coefficients of the cover image. These transform coefficients may not be optimal in terms of the stego image quality and embedding capacity. In this work, the application of Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) have been explored in the context of determining the optimal coefficients in these transforms. Frequency domain transforms such as Bandelet Transform (BT) and Finite Ridgelet Transform (FRIT) are used in combination with GA and PSO to improve the efficiency of the image steganography system.

  11. AN IMPROVED GENETIC ALGORITHM FOR SEARCHING OPTIMAL PARAMETERS IN n—DIMENSIONAL SPACE

    Institute of Scientific and Technical Information of China (English)

    TangBin; HuGuangrui

    2002-01-01

    An improved genetic algorithm for searching optimal parameters in n-dimensional space is presented,which encodes movement direction and distance and searches from coarse to precise.The algorithm can realize global optimization and improve the search efficiency,and can be applied effectively in industrial optimization ,data mining and pattern recognition.

  12. AN IMPROVED GENETIC ALGORITHM FOR SEARCHING OPTIMAL PARAMETERS IN n-DIMENSIONAL SPACE

    Institute of Scientific and Technical Information of China (English)

    Tang Bin; Hu Guangrui

    2002-01-01

    An improved genetic algorithm for searching optimal parameters in n-dimensional space is presented, which encodes movement direction and distance and searches from coarse to precise. The algorithm can realize global optimization and improve the search efficiency, and can be applied effectively in industrial optimization, data mining and pattern recognition.

  13. A small electron donor in cobalt complex electrolyte significantly improves efficiency in dye-sensitized solar cells

    Science.gov (United States)

    Hao, Yan; Yang, Wenxing; Zhang, Lei; Jiang, Roger; Mijangos, Edgar; Saygili, Yasemin; Hammarström, Leif; Hagfeldt, Anders; Boschloo, Gerrit

    2016-12-01

    Photoelectrochemical approach to solar energy conversion demands a kinetic optimization of various light-induced electron transfer processes. Of great importance are the redox mediator systems accomplishing the electron transfer processes at the semiconductor/electrolyte interface, therefore affecting profoundly the performance of various photoelectrochemical cells. Here, we develop a strategy--by addition of a small organic electron donor, tris(4-methoxyphenyl)amine, into state-of-art cobalt tris(bipyridine) redox electrolyte--to significantly improve the efficiency of dye-sensitized solar cells. The developed solar cells exhibit efficiency of 11.7 and 10.5%, at 0.46 and one-sun illumination, respectively, corresponding to a 26% efficiency improvement compared with the standard electrolyte. Preliminary stability tests showed the solar cell retained 90% of its initial efficiency after 250 h continuous one-sun light soaking. Detailed mechanistic studies reveal the crucial role of the electron transfer cascade processes within the new redox system.

  14. Improved Ant Colony Optimization Algorithm based Expert System on Nephrology

    Directory of Open Access Journals (Sweden)

    Sri.N.V.Ramana Murty

    2010-07-01

    Full Text Available Expert system Nephrology is a computer program that exhibits, within a specific domain, a degree of expertise in problem solving that is comparable to that of a human expert. The knowledge base consistsof information about a particular problem area. This information is collected from domain experts (doctors. This system mainly contains two modules one is Information System and the other is Expert Advisory system. The Information System contains the static information about different diseases and drugs in the field of Nephrology. This information system helps the patients /users to know about the problems related to kidneys. The Nephrology Advisory system helps the Patients /users to get the required and suitable advice depending on their queries. This medical expert system is developedusing Java Server Pages (JSP as front-end and MYSQL database as Backend in such a way that all the activities are carried out in a user-friendly manner. Improved Ant Colony Optimization Algorithm (ACO along with RETE algorithm is also used for better results.

  15. Parameter definition using vibration prediction software leads to significant drilling performance improvements

    Energy Technology Data Exchange (ETDEWEB)

    Amorim, Dalmo; Hanley, Chris Hanley; Fonseca, Isaac; Santos, Juliana [National Oilwell Varco, Houston TX (United States); Leite, Daltro J.; Borella, Augusto; Gozzi, Danilo [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    field monitoring. Vibration prediction diminishes the importance of trial-and-error procedures such as drill-off tests, which are valid only for short sections. It also solves an existing lapse in Mechanical Specific Energy (MSE) real-time drilling control programs applying the theory of Teale, which states that a drilling system is perfectly efficient when it spends the exact energy to overcome the in situ rock strength. Using the proprietary software tool this paper will examine the resonant vibration modes that may be initiated while drilling with different BHA's and drill string designs, showing that the combination of a proper BHA design along with the correct selection of input parameters results in an overall improvement to drilling efficiency. Also, being the BHA predictively analyzed, it will be reduced the potential for vibration or stress fatigue in the drill string components, leading to a safer operation. In the recent years there has been an increased focus on vibration detection, analysis, and mitigation techniques, where new technologies, like the Drilling Dynamics Data Recorders (DDDR), may provide the capability to capture high frequency dynamics data at multiple points along the drilling system. These tools allow the achievement of drilling performance improvements not possible before, opening a whole new array of opportunities for optimization and for verification of predictions calculated by the drill string dynamics modeling software tool. The results of this study will identify how the dynamics from the drilling system, interacting with formation, directly relate to inefficiencies and to the possible solutions to mitigate drilling vibrations in order to improve drilling performance. Software vibration prediction and downhole measurements can be used for non-drilling operations like drilling out casing or reaming, where extremely high vibration levels - devastating to the cutting structure of the bit before it has even touched bottom - have

  16. Neuro-Linguistic Programming: Improving Rapport between Track/Cross Country Coaches and Significant Others

    Science.gov (United States)

    Helm, David Jay

    2017-01-01

    This study examines the background information and the components of N.L.P., being eye movements, use of predicates, and posturing, as they apply to improving rapport and empathy between track/cross country coaches and their significant others in the arena of competition to help alleviate the inherent stressors.

  17. Inhibition of class IIb histone deacetylase significantly improves cloning efficiency in mice.

    Science.gov (United States)

    Ono, Tetsuo; Li, Chong; Mizutani, Eiji; Terashita, Yukari; Yamagata, Kazuo; Wakayama, Teruhiko

    2010-12-01

    Since the first mouse clone was produced by somatic cell nuclear transfer, the success rate of cloning in mice has been extremely low. Some histone deacetylase inhibitors, such as trichostatin A and scriptaid, have improved the full-term development of mouse clones significantly, but the mechanisms allowing for this are unclear. Here, we found that two other specific inhibitors, suberoylanilide hydroxamic acid and oxamflatin, could also reduce the rate of apoptosis in blastocysts, improve the full-term development of cloned mice, and increase establishment of nuclear transfer-generated embryonic stem cell lines significantly without leading to obvious abnormalities. However, another inhibitor, valproic acid, could not improve cloning efficiency. Suberoylanilide hydroxamic acid, oxamflatin, trichostatin A, and scriptaid are inhibitors for classes I and IIa/b histone deacetylase, whereas valproic acid is an inhibitor for classes I and IIa, suggesting that inhibiting class IIb histone deacetylase is an important step for reprogramming mouse cloning efficiency.

  18. Significance of relative position of cellulases in designer cellulosomes for optimized cellulolysis.

    Directory of Open Access Journals (Sweden)

    Johanna Stern

    Full Text Available Degradation of cellulose is of major interest in the quest for alternative sources of renewable energy, for its positive effects on environment and ecology, and for use in advanced biotechnological applications. Due to its microcrystalline organization, celluose is extremely difficult to degrade, although numerous microbes have evolved that produce the appropriate enzymes. The most efficient known natural cellulolytic system is produced by anaerobic bacteria, such as C. thermocellum, that possess a multi-enzymatic complex termed the cellulosome. Our laboratory has devised and developed the designer cellulosome concept, which consists of chimaeric scaffoldins for controlled incorporation of recombinant polysaccharide-degrading enzymes. Recently, we reported the creation of a combinatorial library of four cellulosomal modules comprising a basic chimaeric scaffoldin, i.e., a CBM and 3 divergent cohesin modules. Here, we employed selected members of this library to determine whether the position of defined cellulolytic enzymes is important for optimized degradation of a microcrystalline cellulosic substrate. For this purpose, 10 chimaeric scaffoldins were used for incorporation of three recombinant Thermobifida fusca enzymes: the processive endoglucanase Cel9A, endoglucanase Cel5A and exoglucanase Cel48A. In addition, we examined whether the characteristic properties of the T. fusca enzymes as designer cellulosome components are unique to this bacterium by replacing them with parallel enzymes from Clostridium thermocellum. The results support the contention that for a given set of cellulosomal enzymes, their relative position within a scaffoldin can be critical for optimal degradation of microcrystaline cellulosic substrates.

  19. Substantial Progress Yet Significant Opportunity for Improvement in Stroke Care in China.

    Science.gov (United States)

    Li, Zixiao; Wang, Chunjuan; Zhao, Xingquan; Liu, Liping; Wang, Chunxue; Li, Hao; Shen, Haipeng; Liang, Li; Bettger, Janet; Yang, Qing; Wang, David; Wang, Anxin; Pan, Yuesong; Jiang, Yong; Yang, Xiaomeng; Zhang, Changqing; Fonarow, Gregg C; Schwamm, Lee H; Hu, Bo; Peterson, Eric D; Xian, Ying; Wang, Yilong; Wang, Yongjun

    2016-11-01

    Stroke is a leading cause of death in China. Yet the adherence to guideline-recommended ischemic stroke performance metrics in the past decade has been previously shown to be suboptimal. Since then, several nationwide stroke quality management initiatives have been conducted in China. We sought to determine whether adherence had improved since then. Data were obtained from the 2 phases of China National Stroke Registries, which included 131 hospitals (12 173 patients with acute ischemic stroke) in China National Stroke Registries phase 1 from 2007 to 2008 versus 219 hospitals (19 604 patients) in China National Stroke Registries phase 2 from 2012 to 2013. Multiple regression models were developed to evaluate the difference in adherence to performance measure between the 2 study periods. The overall quality of care has improved over time, as reflected by the higher composite score of 0.76 in 2012 to 2013 versus 0.63 in 2007 to 2008. Nine of 13 individual performance metrics improved. However, there were no significant improvements in the rates of intravenous thrombolytic therapy and anticoagulation for atrial fibrillation. After multivariate analysis, there remained a significant 1.17-fold (95% confidence interval, 1.14-1.21) increase in the odds of delivering evidence-based performance metrics in the more recent time periods versus older data. The performance metrics with the most significantly increased odds included stroke education, dysphagia screening, smoking cessation, and antithrombotics at discharge. Adherence to stroke performance metrics has increased over time, but significant opportunities remain for further improvement. Continuous stroke quality improvement program should be developed as a national priority in China. © 2016 American Heart Association, Inc.

  20. Improved Glowworm Swarm Optimization Algorithm for Multilevel Color Image Thresholding Problem

    OpenAIRE

    Lifang He; Songwei Huang

    2016-01-01

    The thresholding process finds the proper threshold values by optimizing a criterion, which can be considered as a constrained optimization problem. The computation time of traditional thresholding techniques will increase dramatically for multilevel thresholding. To greatly overcome this problem, swarm intelligence algorithm is widely used to search optimal thresholds. In this paper, an improved glowworm swarm optimization (IGSO) algorithm has been presented to find the optimal multilevel th...

  1. Group mindfulness-based therapy significantly improves sexual desire in women.

    Science.gov (United States)

    Brotto, Lori A; Basson, Rosemary

    2014-06-01

    At least a third of women across reproductive ages experience low sexual desire and impaired arousal. There is increasing evidence that mindfulness, defined as non-judgmental present moment awareness, may improve women's sexual functioning. The goal of this study was to test the effectiveness of mindfulness-based therapy, either immediately or after a 3-month waiting period, in women seeking treatment for low sexual desire and arousal. Women participated in four 90-min group sessions that included mindfulness meditation, cognitive therapy, and education. A total of 117 women were assigned to either the immediate treatment (n = 68, mean age 40.8 yrs) or delayed treatment (n = 49, mean age 42.2 yrs) group, in which women had two pre-treatment baseline assessments followed by treatment. A total of 95 women completed assessments through to the 6-month follow-up period. Compared to the delayed treatment control group, treatment significantly improved sexual desire, sexual arousal, lubrication, sexual satisfaction, and overall sexual functioning. Sex-related distress significantly decreased in both conditions, regardless of treatment, as did orgasmic difficulties and depressive symptoms. Increases in mindfulness and a reduction in depressive symptoms predicted improvements in sexual desire. Mindfulness-based group therapy significantly improved sexual desire and other indices of sexual response, and should be considered in the treatment of women's sexual dysfunction.

  2. Topology optimization for improving the performance of solar cells

    NARCIS (Netherlands)

    Gupta, D.K.; Langelaar, M.; Keulen, F. van; Barink, M.

    2014-01-01

    This work introduces the application of Topology Optimization (TO) to design optimal front metallization patterns for solar cells and increase their power output. A challenging aspect of the solar cell electrode design problem is the strong nonlinear relation between the active layer current and the

  3. An Improved Multiobjective Optimization Evolutionary Algorithm Based on Decomposition for Complex Pareto Fronts.

    Science.gov (United States)

    Jiang, Shouyong; Yang, Shengxiang

    2016-02-01

    The multiobjective evolutionary algorithm based on decomposition (MOEA/D) has been shown to be very efficient in solving multiobjective optimization problems (MOPs). In practice, the Pareto-optimal front (POF) of many MOPs has complex characteristics. For example, the POF may have a long tail and sharp peak and disconnected regions, which significantly degrades the performance of MOEA/D. This paper proposes an improved MOEA/D for handling such kind of complex problems. In the proposed algorithm, a two-phase strategy (TP) is employed to divide the whole optimization procedure into two phases. Based on the crowdedness of solutions found in the first phase, the algorithm decides whether or not to delicate computational resources to handle unsolved subproblems in the second phase. Besides, a new niche scheme is introduced into the improved MOEA/D to guide the selection of mating parents to avoid producing duplicate solutions, which is very helpful for maintaining the population diversity when the POF of the MOP being optimized is discontinuous. The performance of the proposed algorithm is investigated on some existing benchmark and newly designed MOPs with complex POF shapes in comparison with several MOEA/D variants and other approaches. The experimental results show that the proposed algorithm produces promising performance on these complex problems.

  4. Multirunway Optimization Schedule of Airport Based on Improved Genetic Algorithm by Dynamical Time Window

    Directory of Open Access Journals (Sweden)

    Hang Zhou

    2015-01-01

    Full Text Available Reasonable airport runway scheduling is an effective measure to alleviate air traffic congestion. This paper proposes a new model and algorithm for flight scheduling. Considering the factors such as operating conditions and flight safety interval, the runway throughput, flight delays cost, and controller workload composes a multiobjective optimization model. The genetic algorithm combined with sliding time window algorithm is used to solve the model proposed in this paper. Simulation results show that the algorithm presented in this paper gets the optimal results, the runway throughput is increased by 12.87%, the delay cost is reduced by 61.46%, and the controller workload is also significantly reduced compared with FCFS (first come first served. Meanwhile, compared with the general genetic algorithm, it also reduces the time complexity and improves real-time and work efficiency significantly. The analysis results can provide guidance for air traffic controllers to make better air traffic control.

  5. Histone deacetylase inhibitor significantly improved the cloning efficiency of porcine somatic cell nuclear transfer embryos.

    Science.gov (United States)

    Huang, Yongye; Tang, Xiaochun; Xie, Wanhua; Zhou, Yan; Li, Dong; Yao, Chaogang; Zhou, Yang; Zhu, Jianguo; Lai, Liangxue; Ouyang, Hongsheng; Pang, Daxin

    2011-12-01

    Valproic acid (VPA), a histone deacetylase inbibitor, has been shown to generate inducible pluripotent stem (iPS) cells from mouse and human fibroblasts with a significant higher efficiency. Because successful cloning by somatic cell nuclear transfer (SCNT) undergoes a full reprogramming process in which the epigenetic state of a differentiated donor nuclear is converted into an embryonic totipotent state, we speculated that VPA would be useful in promoting cloning efficiency. Therefore, in the present study, we examined whether VPA can promote the developmental competence of SCNT embryos by improving the reprogramming state of donor nucleus. Here we report that 1 mM VPA for 14 to 16 h following activation significantly increased the rate of blastocyst formation of porcine SCNT embryos constructed from Landrace fetal fibroblast cells compared to the control (31.8 vs. 11.4%). However, we found that the acetylation level of Histone H3 lysine 14 and Histone H4 lysine 5 and expression level of Oct4, Sox2, and Klf4 was not significantly changed between VPA-treated and -untreated groups at the blastocyst stage. The SCNT embryos were transferred to 38 surrogates, and the cloning efficiency in the treated group was significantly improved compared with the control group. Taken together, we have demonstrated that VPA can improve both in vitro and in vivo development competence of porcine SCNT embryos.

  6. Improving multi-objective reservoir operation optimization with sensitivity-informed dimension reduction

    Science.gov (United States)

    Chu, J.; Zhang, C.; Fu, G.; Li, Y.; Zhou, H.

    2015-08-01

    This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed method dramatically reduces the computational demands required for attaining high-quality approximations of optimal trade-off relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed dimension reduction and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform dimension reduction of optimization problems when solving complex multi-objective reservoir operation problems.

  7. Optimizing Combination of Units Commitment Based on Improved Genetic Algorithms

    Institute of Scientific and Technical Information of China (English)

    LAI Yifei; ZHANG Qianhua; JIA Junping

    2007-01-01

    GAs are general purpose optimization techniques based on principles inspired from the biological evolution using metaphors of mechanisms, such as natural selection, genetic recombination and survival of the fittest. By use of coding betterment, the dynamic changes of the mutation rate and the crossover probability, the dynamic choice of subsistence, the reservation of the optimal fitness value, a modified genetic algorithm for optimizing combination of units in thermal power plants is proposed.And through taking examples, test result are analyzed and compared with results of some different algorithms. Numerical results show available value for the unit commitment problem with examples.

  8. Optimization of the tumor microenvironment and nanomedicine properties simultaneously to improve tumor therapy.

    Science.gov (United States)

    Zhang, Bo; Shi, Wei; Jiang, Ting; Wang, Lanting; Mei, Heng; Lu, Heng; Hu, Yu; Pang, Zhiqing

    2016-09-20

    Effective delivery of nanomedicines to tumor tissues depends on both the tumor microenvironment and nanomedicine properties. Accordingly, tumor microenvironment modification or advanced design of nanomedicine was emerging to improve nanomedicine delivery to tumors. However, few studies have emphasized the necessity to optimize the tumor microenvironment and nanomedicine properties simultaneously to improve tumor treatment. In the present study, imatinib mesylate (IMA) was used to normalize the tumor microenvironment including platelet-derived growth factor receptor-β expression inhibition, tumor vessel normalization, and tumor perfusion improvement as demonstrated by immunofluorescence staining. In addition, the effect of tumor microenvironment normalization on tumor delivery of nanomedicines with different sizes was carefully investigated. It was shown that IMA treatment significantly reduced the accumulation of nanoparticles (NPs) around 110 nm but enhanced the accumulation of micelles around 23 nm by in vivo fluorescence imaging experiment. Furthermore, IMA treatment limited the distribution of NPs inside tumors but increased that of micelles with a more homogeneous pattern. Finally, the anti-tumor efficacy study displayed that IMA pretreatment could significantly increase the therapeutic effects of paclitaxel-loaded micelles. All-together, a new strategy to improve nanomedicine delivery to tumor was provided by optimizing both nanomedicine size and the tumor microenvironment simultaneously, and it will have great potential in clinics for tumor treatment.

  9. Optimization of the tumor microenvironment and nanomedicine properties simultaneously to improve tumor therapy

    Science.gov (United States)

    Jiang, Ting; Wang, Lanting; Mei, Heng; Lu, Heng; Hu, Yu; Pang, Zhiqing

    2016-01-01

    Effective delivery of nanomedicines to tumor tissues depends on both the tumor microenvironment and nanomedicine properties. Accordingly, tumor microenvironment modification or advanced design of nanomedicine was emerging to improve nanomedicine delivery to tumors. However, few studies have emphasized the necessity to optimize the tumor microenvironment and nanomedicine properties simultaneously to improve tumor treatment. In the present study, imatinib mesylate (IMA) was used to normalize the tumor microenvironment including platelet-derived growth factor receptor-β expression inhibition, tumor vessel normalization, and tumor perfusion improvement as demonstrated by immunofluorescence staining. In addition, the effect of tumor microenvironment normalization on tumor delivery of nanomedicines with different sizes was carefully investigated. It was shown that IMA treatment significantly reduced the accumulation of nanoparticles (NPs) around 110 nm but enhanced the accumulation of micelles around 23 nm by in vivo fluorescence imaging experiment. Furthermore, IMA treatment limited the distribution of NPs inside tumors but increased that of micelles with a more homogeneous pattern. Finally, the anti-tumor efficacy study displayed that IMA pretreatment could significantly increase the therapeutic effects of paclitaxel-loaded micelles. All-together, a new strategy to improve nanomedicine delivery to tumor was provided by optimizing both nanomedicine size and the tumor microenvironment simultaneously, and it will have great potential in clinics for tumor treatment. PMID:27566585

  10. Communication: Proper treatment of classically forbidden electronic transitions significantly improves detailed balance in surface hopping.

    Science.gov (United States)

    Sifain, Andrew E; Wang, Linjun; Prezhdo, Oleg V

    2016-06-01

    Surface hopping is the most popular method for nonadiabatic molecular dynamics. Many have reported that it does not rigorously attain detailed balance at thermal equilibrium, but does so approximately. We show that convergence to the Boltzmann populations is significantly improved when the nuclear velocity is reversed after a classically forbidden hop. The proposed prescription significantly reduces the total number of classically forbidden hops encountered along a trajectory, suggesting that some randomization in nuclear velocity is needed when classically forbidden hops constitute a large fraction of attempted hops. Our results are verified computationally using two- and three-level quantum subsystems, coupled to a classical bath undergoing Langevin dynamics.

  11. Collaborative Project: Building improved optimized parameter estimation algorithms to improve methane and nitrogen fluxes in a climate model

    Energy Technology Data Exchange (ETDEWEB)

    Mahowald, Natalie [Cornell Univ., Ithaca, NY (United States)

    2016-11-29

    earth science with limited numbers of simulations; and, c) will be (as part of the proposed research) significantly improved both by adding asynchronous parallelism, early truncation of unsuccessful simulations, and the improvement of both serial and parallel performance by the use of derivative and sensitivity information from global and local surrogate approximations S(x). The algorithm development and testing will be focused on the CLM-ME/N model application, but the methods are general and are expected to also perform well on optimization for parameter estimation of other climate models and other classes of continuous multimodal optimization problems arising from complex simulation models. In addition, this proposal will compile available datasets of emissions of methane, nitrous oxides and reactive nitrogen species and develop protocols for site level comparisons with the CLM-ME/N. Once the model parameters are optimized against site level data, the model will be simulated at the global level and compared to atmospheric concentration measurements for the current climate, and future emissions will be estimated using climate change as simulated by the CESM. This proposal combines experts in earth system modeling, optimization, computer science, and process level understanding of soil gas emissions in an interdisciplinary team in order to improve the modeling of methane and nitrogen gas emissions. This proposal thus meets the requirements of the SciDAC RFP, by integrating state-of-the-art computer science and earth system to build an improved earth system model.

  12. Significant performance improvement obtained in a wireless mesh network using a beamswitching antenna

    CSIR Research Space (South Africa)

    Lysko, AA

    2012-09-01

    Full Text Available , beamswitching, parasitic array I. INTRODUCTION The wireless communications experience significant growth, which can be expected to continue for at least one- two decades due to steadily growing demand and introduction of new technologies bandwidth hungry... to improve the throughput in a wireless network by an order of magnitude. . VI. REFERENCES [1] C. Balanis, Antenna Theory: Analysis and Design. 3rd Ed, Willey, 2005, 1136p. [2] C. Balanis, Introduction to Smart Antennas (Synthesis Lectures...

  13. Optimization of technical measures for improving high-temperature performance of asphalt-rubber mixture

    Institute of Scientific and Technical Information of China (English)

    Chuan Xiao; Tianqing Ling; Yanjun Qiu

    2013-01-01

    Asphalt-rubber pavements often become dam-aged in high-temperature regions and appear rutted or wavy, and experience slippage. To improve the high-tem-perature performance of the asphalt-rubber mixture, tech-nical measurements, such as, the optimal adjustment of gradation, technique of composite modification, and con-trol of compaction were investigated. An optimal adjust-ment of aggregate gradation based on stone matrix asphalt improves the high-temperature stability of the asphalt-rubber mixture significantly. Through composite modifi-cation, the effect of asphalt-rubber modification was enhanced, and the dynamic stability and relative defor-mation indices of the asphalt-rubber mixture were improved significantly. Furthermore, compaction parame-ters had a significant influence on the high-temperature stability of the asphalt-rubber mixture. The rolling times for compacting the asphalt-rubber mixture should be controlled to within 18-20 round-trips at a molding tem-perature at 180 ?C;if the rolling time is a 12 round-trip, the compaction temperature of the asphalt-rubber mixture should be controlled between 180 and 190 ?C.

  14. An improved technique for the prediction of optimal image resolution ...

    African Journals Online (AJOL)

    user

    2010-10-04

    Oct 4, 2010 ... Key words: Optimal resolution, savannah ecosystems, image noise index, land cover index, .... Most techniques, including those employed by Mugisha .... Resampling imagery using cubic convolution was used because it.

  15. Improved Large-Scale Process Cooling Operation through Energy Optimization

    Directory of Open Access Journals (Sweden)

    Kriti Kapoor

    2013-11-01

    Full Text Available This paper presents a study based on real plant data collected from chiller plants at the University of Texas at Austin. It highlights the advantages of operating the cooling processes based on an optimal strategy. A multi-component model is developed for the entire cooling process network. The model is used to formulate and solve a multi-period optimal chiller loading problem, posed as a mixed-integer nonlinear programming (MINLP problem. The results showed that an average energy savings of 8.57% could be achieved using optimal chiller loading as compared to the historical energy consumption data from the plant. The scope of the optimization problem was expanded by including a chilled water thermal storage in the cooling system. The effect of optimal thermal energy storage operation on the net electric power consumption by the cooling system was studied. The results include a hypothetical scenario where the campus purchases electricity at wholesale market prices and an optimal hour-by-hour operating strategy is computed to use the thermal energy storage tank.

  16. Optimal Compression of Floating-point Astronomical Images Without Significant Loss of Information

    CERN Document Server

    Pence, W D; Seaman, R

    2010-01-01

    We describe a compression method for floating-point astronomical images that gives compression ratios of 6 -- 10 while still preserving the scientifically important information in the image. The pixel values are first preprocessed by quantizing them into scaled integer intensity levels, which removes some of the uncompressible noise in the image. The integers are then losslessly compressed using the fast and efficient Rice algorithm and stored in a portable FITS format file. Quantizing an image more coarsely gives greater image compression, but it also increases the noise and degrades the precision of the photometric and astrometric measurements in the quantized image. Dithering the pixel values during the quantization process can greatly improve the precision of measurements in the images. This is especially important if the analysis algorithm relies on the mode or the median which would be similarly quantized if the pixel values are not dithered. We perform a series of experiments on both synthetic and real...

  17. Optimal Compression of Floating-Point Astronomical Images Without Significant Loss of Information

    Science.gov (United States)

    Pence, William D.; White, R. L.; Seaman, R.

    2010-01-01

    We describe a compression method for floating-point astronomical images that gives compression ratios of 6 - 10 while still preserving the scientifically important information in the image. The pixel values are first preprocessed by quantizing them into scaled integer intensity levels, which removes some of the uncompressible noise in the image. The integers are then losslessly compressed using the fast and efficient Rice algorithm and stored in a portable FITS format file. Quantizing an image more coarsely gives greater image compression, but it also increases the noise and degrades the precision of the photometric and astrometric measurements in the quantized image. Dithering the pixel values during the quantization process greatly improves the precision of measurements in the more coarsely quantized images. We perform a series of experiments on both synthetic and real astronomical CCD images to quantitatively demonstrate that the magnitudes and positions of stars in the quantized images can be measured with the predicted amount of precision. In order to encourage wider use of these image compression methods, we have made available a pair of general-purpose image compression programs, called fpack and funpack, which can be used to compress any FITS format image.

  18. PXD101 significantly improves nuclear reprogramming and the in vitro developmental competence of porcine SCNT embryos

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Jun-Xue; Kang, Jin-Dan; Li, Suo; Jin, Long; Zhu, Hai-Ying; Guo, Qing; Gao, Qing-Shan; Yan, Chang-Guo; Yin, Xi-Jun, E-mail: yinxj33@msn.com

    2015-01-02

    Highlights: • First explored that the effects of PXD101 on the development of SCNT embryos in vitro. • 0.5 μM PXD101 treated for 24 h improved the development of porcine SCNT embryos. • Level of AcH3K9 was significantly higher than control group at early stages. - Abstract: In this study, we investigated the effects of the histone deacetylase inhibitor PXD101 (belinostat) on the preimplantation development of porcine somatic cell nuclear transfer (SCNT) embryos and their expression of the epigenetic markers histone H3 acetylated at lysine 9 (AcH3K9). We compared the in vitro developmental competence of SCNT embryos treated with various concentrations of PXD101 for 24 h. Treatment with 0.5 μM PXD101 significantly increased the proportion of SCNT embryos that reached the blastocyst stage, in comparison to the control group (23.3% vs. 11.5%, P < 0.05). We tested the in vitro developmental competence of SCNT embryos treated with 0.5 μM PXD101 for various amounts of times following activation. Treatment for 24 h significantly improved the development of porcine SCNT embryos, with a significantly higher proportion of embryos reaching the blastocyst stage in comparison to the control group (25.7% vs. 10.6%, P < 0.05). PXD101-treated SCNT embryos were transferred into two surrogate sows, one of whom became pregnant and four fetuses developed. PXD101 treatment significantly increased the fluorescence intensity of immunostaining for AcH3K9 in embryos at the pseudo-pronuclear and 2-cell stages. At these stages, the fluorescence intensities of immunostaining for AcH3K9 were significantly higher in PXD101-treated embryos than in control untreated embryos. In conclusion, this study demonstrates that PXD101 can significantly improve the in vitro and in vivo developmental competence of porcine SCNT embryos and can enhance their nuclear reprogramming.

  19. Behaviorally inhibited individuals demonstrate significantly enhanced conditioned response acquisition under non-optimal learning conditions.

    Science.gov (United States)

    Holloway, J L; Allen, M T; Myers, C E; Servatius, R J

    2014-03-15

    Behavioral inhibition (BI) is an anxiety vulnerability factor associated with hypervigilance to novel stimuli, threat, and ambiguous cues. The progression from anxiety risk to a clinical disorder is unknown, although the acquisition of defensive learning and avoidance may be a critical feature. As the expression of avoidance is also central to anxiety development, the present study examined avoidance acquisition as a function of inhibited temperament using classical eyeblink conditioning. Individuals were classified as behaviorally inhibited (BI) or non-inhibited (NI) based on combined scores from the Adult and Retrospective Measures of Behavioural Inhibition (AMBI and RMBI, respectively). Acquisition was assessed using delay, omission, or yoked conditioning schedules of reinforcement. Omission training was identical to delay, except that the emission of an eyeblink conditioned response (CR) resulted in omission of the unconditioned airpuff stimulus (US) on that trial. Each subject in the yoked group was matched on total BI score to a subject in the omission group, and received the same schedule of CS and US delivery, resulting in a partial reinforcement training schedule. Delay conditioning elicited significantly more CRs compared to the omission and yoked contingencies, the latter two of which did not differ from each other. Thus, acquisition of an avoidance response was not apparent. BI individuals demonstrated enhanced acquisition overall, while partial reinforcement training significantly distinguished between BI and NI groups. Enhanced learning in BI may be a function of an increased defensive learning capacity, or sensitivity to uncertainty. Further work examining the influence of BI on learning acquisition is important for understanding individual differences in disorder etiology in anxiety vulnerable cohorts.

  20. Improvement of spergualin production by mutation and medium optimization

    Institute of Scientific and Technical Information of China (English)

    SHI Yingzi; MA Guangpeng; WU Xiangjin; JIANG Ling; WANG Xiangjing; BAI Hua

    2007-01-01

    In order to screen a high-yield spergualin-production strain and an optimal fermentation medium, large numbers of isolates were selected after ultraviolet (UV) mutation and self-tolerant mutation of Bacillus laterosporus A7. A high-yield strain A-94-7 was obtained and the spergualin productivity was 4.1-fold of the parent strain. The genetic stability of the high-yield strain Bacillus laterosporus A-94-7 was very good. After fermentation medium optimization, Bacillus laterosporus A-94-7 was able to produce 380 mg·L-1. The spergualin productivity in Bacillus laterosporus A7 was increased 4.75-fold by mutation and medium optimization.

  1. Improving Convergence of Iterative Feedback Tuning using Optimal External Perturbations

    DEFF Research Database (Denmark)

    Huusom, Jakob Kjøbsted; Hjalmarsson, Håkon; Poulsen, Niels Kjølstad

    2008-01-01

    Iterative feedback tuning constitutes an attractive control loop tuning method for processes in the absence of sufficient process insight. It is a purely data driven approach to optimization of the loop performance. The standard formulation ensures an unbiased estimate of the loop performance cost...... function gradient, which is used in a search algorithm. A slow rate of convergence of the tuning method is often experienced when tuning for disturbance rejection. This is due to a poor signal to noise ratio in the process data. A method is proposed for increasing the information content in data...... by introducing an optimal perturbation signal in the tuning algorithm. For minimum variance control design the optimal design of an external perturbation signal is derived in terms of the asymptotic accuracy of the iterative feedback tuning method....

  2. Significant Improvement in Survival after Unrelated Donor Hematopoietic Cell Transplantation in the Recent Era

    Science.gov (United States)

    Majhail, Navneet S; Chitphakdithai, Pintip; Logan, Brent; King, Roberta; Devine, Steven; Rossmann, Susan N; Hale, Gregory; Hartzman, Robert J; Karanes, Chatchada; Laport, Ginna G; Nemecek, Eneida; Snyder, Edward L; Switzer, Galen E; Miller, John; Navarro, Willis; Confer, Dennis L; Levine, John E

    2014-01-01

    Patients and physicians may defer unrelated donor hematopoietic cell transplantation (HCT) as curative therapy due to mortality risk associated with the procedure. Therefore, it is important for physicians to know the current outcomes data when counseling potential candidates. To provide this information, we evaluated 15,059 unrelated donor HCT recipients between 2000-2009. We compared outcomes before and after 2005 for four cohorts: age <18 years with malignant diseases (N=1,920), 18-59 years with malignant diseases (N=9,575), ≥60 years with malignant diseases (N=2,194), and non-malignant diseases (N=1,370). Three-year overall survival in 2005-2009 was significantly better in all four cohorts (<18 years: 55% vs. 45%, 18-59 years: 42% vs. 35%, ≥60 years: 35% vs. 25%, non-malignant diseases: 69% vs. 60%, P<0.001 for all comparisons). Multivariate analyses in leukemia patients receiving HLA 7-8/8 matched transplants showed significant reduction in overall and non-relapse mortality in the first 1-year after HCT among patients transplanted in 2005-2009; however, risks for relapse did not change over time. Significant survival improvements after unrelated donor HCT have occurred over the recent decade and can be partly explained by better patient selection (e.g., HCT earlier in the disease course and lower disease risk), improved donor selection (e.g., more precise allele-level matched unrelated donors) and changes in transplant practices. PMID:25445638

  3. Nasal irrigation with saline solution significantly improves oxygen saturation in infants with bronchiolitis.

    Science.gov (United States)

    Schreiber, Silvana; Ronfani, Luca; Ghirardo, Sergio; Minen, Federico; Taddio, Andrea; Jaber, Mohamad; Rizzello, Elisa; Barbi, Egidio

    2016-03-01

    Published guidelines do not recommend nasal irrigation in bronchiolitis, but it is common practice in Italy, despite a lack of data on its benefits or adverse effects. This single-blind, multicentre, randomised controlled trial compared nasal irrigation using either isotonic 0.9% sodium chloride or hypertonic 3% sodium chloride with simple supportive care in infants with bronchiolitis. We randomly assigned 133 infants up one year of age, who were admitted to the emergency department with bronchiolitis and an oxygen saturation (SpO2) of between 88 and 94%, to the isotonic (n = 47), hypertonic (n = 44) or standard care (n = 42) groups. Variations in SpO2 and the wheeze, air exchange, respiratory rate, muscle use (WARM) respiratory distress score were recorded at zero, five, 15, 20 and 50 minutes. Five minutes after the intervention, the median SpO2 value (95%) in the isotonic group was higher than both the hypertonic (94%) and the standard care (93%) groups. The differences between the isotonic and standard treatment groups were statistically significant at each time point, while the hypertonic group only reached significantly higher values after 50 minutes. However, the WARM score did not improve. A single nasal irrigation with saline solution significantly improved oxygen saturation in infants with bronchiolitis. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  4. Codon-optimized antibiotic resistance gene improves efficiency of transient transformation in Frankia

    Indian Academy of Sciences (India)

    Ken-ichi Kucho; Kentaro Kakoi; Masatoshi Yamaura; Mari Iwashita; Mikiko Abe; Toshiki Uchiumi

    2013-11-01

    Frankia is a unique actinobacterium having abilities to fix atmospheric dinitrogen and to establish endosymbiosis with trees, but molecular bases underlying these interesting characteristics are poorly understood because of a lack of stable transformation system. Extremely high GC content of Frankia genome (> 70%) can be a hindrance to successful transformation. We generated a synthetic gentamicin resistance gene whose codon usage is optimized to Frankia (fgmR) and evaluated its usefulness as a selection marker using a transient transformation system. Success rate of transient transformation and cell growth in selective culture were significantly increased by use of fgmR instead of a native gentamicin resistance gene, suggesting that codon optimization improved translation efficiency of the marker gene and increased antibiotic resistance. Our result shows that similarity in codon usage pattern is an important factor to be taken into account when exogenous transgenes are expressed in Frankia cells.

  5. An improved partial SPIHT with classified weighted rate-distortion optimization for interferential multispectral image compression

    Institute of Scientific and Technical Information of China (English)

    Keyan Wang; Chengke Wu; Fanqiang Kong; Lei Zhang

    2008-01-01

    Based on the property analysis of interferential multispectral images, a novel compression algorithm of partial set partitioning in hierarchical trees (SPIHT) with classified weighted rate-distortion optimization is presented.After wavelet decomposition, partial SPIHT is applied to each zero tree independently by adaptively selecting one of three coding modes according to the probability of the significant coefficients in each bitplane.Meanwhile the interferential multispectral image is partitioned into two kinds of regions in terms of luminous intensity, and the rate-distortion slopes of zero trees are then lifted with classified weights according to their distortion contribution to the constructed spectrum.Finally a global ratedistortion optimization truncation is performed.Compared with the conventional methods, the proposed algorithm not only improves the performance in spatial domain but also reduces the distortion in spectral domain.

  6. Experimental verification of optically optimized CuGaSe2 top cell for improving chalcopyrite tandems*

    Directory of Open Access Journals (Sweden)

    Lux-Steiner M. Ch.

    2010-10-01

    Full Text Available An efficient tandem solar cell requires a top cell which is highly transparent below the energy gap of its absorber. Previously we had reported on a theoretically optimized CuGaSe2 top cell stack based on realistic material properties. It promised a significant increase in optical transparency and, consequently, enhanced CuGaSe2/Cu(In,GaSe2 tandem efficiency. Here we present the first steps taken towards the experimental realization of this optimized tandem. We started with a mechanically stacked device which achieved 8.5% efficiency. Optical measurements of the improved top cells and corresponding photo current densities of the filtered bottom cell are reported. The experimental findings are in agreement with the optical modeling. These data are used to assess the level of tandem performance that could be accomplished in the near future and to discuss the priorities of further research.

  7. Performance Improvement of Adsorption Refrigerating Machines by the Application of a Global Optimization Method

    Science.gov (United States)

    Miyazaki, Takahiko; Akisawa, Atsushi; Kashiwagi, Takao; Akahira, Akira

    The study used the particle swarm optimization to maximize the specific cooling capacity (SCC) of a single-stage adsorption chiller, as well as to maximize the coefficient of performance (COP) at part load conditions of the chiller. The cycle time, which consists of adsorption/desorption time and pre-heating/ pre-cooling time, was chosen as a design parameter. The simulation results of a mathematical model showed a good agreement with experimental results on SCC and COP. It was shown that the SCC could be improved by the optimum cycle time as much as by 30% compared with that by the fixed cycle time. It was also presented that the part load COP would be significantly increased by the cycle time optimization at part load conditions.

  8. A peptide-retrieval strategy enables significant improvement of quantitative performance without compromising confidence of identification.

    Science.gov (United States)

    Tu, Chengjian; Shen, Shichen; Sheng, Quanhu; Shyr, Yu; Qu, Jun

    2017-01-30

    Reliable quantification of low-abundance proteins in complex proteomes is challenging largely owing to the limited number of spectra/peptides identified. In this study we developed a straightforward method to improve the quantitative accuracy and precision of proteins by strategically retrieving the less confident peptides that were previously filtered out using the standard target-decoy search strategy. The filtered-out MS/MS spectra matched to confidently-identified proteins were recovered, and the peptide-spectrum-match FDR were re-calculated and controlled at a confident level of FDR≤1%, while protein FDR maintained at ~1%. We evaluated the performance of this strategy in both spectral count- and ion current-based methods. >60% increase of total quantified spectra/peptides was respectively achieved for analyzing a spike-in sample set and a public dataset from CPTAC. Incorporating the peptide retrieval strategy significantly improved the quantitative accuracy and precision, especially for low-abundance proteins (e.g. one-hit proteins). Moreover, the capacity of confidently discovering significantly-altered proteins was also enhanced substantially, as demonstrated with two spike-in datasets. In summary, improved quantitative performance was achieved by this peptide recovery strategy without compromising confidence of protein identification, which can be readily implemented in a broad range of quantitative proteomics techniques including label-free or labeling approaches. We hypothesize that more quantifiable spectra and peptides in a protein, even including less confident peptides, could help reduce variations and improve protein quantification. Hence the peptide retrieval strategy was developed and evaluated in two spike-in sample sets with different LC-MS/MS variations using both MS1- and MS2-based quantitative approach. The list of confidently identified proteins using the standard target-decoy search strategy was fixed and more spectra/peptides with less

  9. The Improvement of Quantum Genetic Algorithm and Its Application on Function Optimization

    OpenAIRE

    Huaixiao Wang; Jianyong Liu; Jun Zhi; Chengqun Fu

    2013-01-01

    To accelerate the evolutionary process and increase the probability to find the optimal solution, the following methods are proposed to improve the conventional quantum genetic algorithm: an improved method to determine the rotating angle, the self-adaptive rotating angle strategy, adding the quantum mutation operation and quantum disaster operation. The efficiency and accuracy to search the optimal solution of the algorithm are greatly improved. Simulation test shows that the improved quantu...

  10. Improving Growth and Productivity of Oleiferous Brassicas under Changing Environment: Significance of Nitrogen and Sulphur Nutrition, and Underlying Mechanisms

    Directory of Open Access Journals (Sweden)

    Naser A. Anjum

    2012-01-01

    Full Text Available Mineral nutrients are the integral part of the agricultural systems. Among important plant nutrients, nitrogen (N and sulphur (S are known essential elements for growth, development, and various physiological functions in plants. Oleiferous brassicas (rapeseed and mustard require higher amounts of S in addition to N for optimum growth and yield. Therefore, balancing S-N fertilization, optimization of nutrient replenishment, minimization of nutrient losses to the environment, and the concept of coordination in action between S and N could be a significant strategy for improvement of growth and productivity of oleiferous brassicas. Additionally, positive interaction between S and N has been reported to be beneficial for various aspects of oilseed brassicas. The current paper updates readers on the significance of N and S for the improvement of plant growth, development, and productivity in detail. In addition, S-N nutrition-mediated control of major plant antioxidant defense system components involved in the removal and/or metabolism of stress-induced/generated reactive oxygen species in plants (hence, the control of plant growth, development, and productivity has been overviewed.

  11. Improving growth and productivity of Oleiferous Brassicas under changing environment: significance of nitrogen and sulphur nutrition, and underlying mechanisms.

    Science.gov (United States)

    Anjum, Naser A; Gill, Sarvajeet S; Umar, Shahid; Ahmad, Iqbal; Duarte, Armando C; Pereira, Eduarda

    2012-01-01

    Mineral nutrients are the integral part of the agricultural systems. Among important plant nutrients, nitrogen (N) and sulphur (S) are known essential elements for growth, development, and various physiological functions in plants. Oleiferous brassicas (rapeseed and mustard) require higher amounts of S in addition to N for optimum growth and yield. Therefore, balancing S-N fertilization, optimization of nutrient replenishment, minimization of nutrient losses to the environment, and the concept of coordination in action between S and N could be a significant strategy for improvement of growth and productivity of oleiferous brassicas. Additionally, positive interaction between S and N has been reported to be beneficial for various aspects of oilseed brassicas. The current paper updates readers on the significance of N and S for the improvement of plant growth, development, and productivity in detail. In addition, S-N nutrition-mediated control of major plant antioxidant defense system components involved in the removal and/or metabolism of stress-induced/generated reactive oxygen species in plants (hence, the control of plant growth, development, and productivity) has been overviewed.

  12. Describing Assay Precision-Reciprocal of Variance Is Correct, Not CV Percent: Its Use Should Significantly Improve Laboratory Performance.

    Science.gov (United States)

    Jelliffe, Roger W; Schumitzky, Alan; Bayard, David; Fu, Xiaowei; Neely, Michael

    2015-06-01

    Describing assay error as percent coefficient of variation (CV%) fails as measurements approach zero. Results are censored if below some arbitrarily chosen lower limit of quantification (LLOQ). CV% gives incorrect weighting to data obtained by therapeutic drug monitoring, with incorrect parameter values in the resulting pharmacokinetic models, and incorrect dosage regimens for patient care. CV% was compared with the reciprocal of the variance (1/var) of each assay measurement. This method has not been considered by the laboratory community. A simple description of assay standard deviation (SD) as a polynomial function of the assay measurement over its working range was developed, the reciprocal of the assay variance determined, and its results compared with CV%. CV% does not provide correct weighting of measured serum concentrations as required for optimal therapeutic drug monitoring. It does not permit optimally individualized models of the behavior of a drug in a patient, resulting in incorrect dosage regimens. The assay error polynomial described here, using 1/var, provides correct weighting of such data, all the way down to and including zero. There is no need to censor low results, and no need to set any arbitrary LLOQ. Reciprocal of variance is the correct measure of assay precision and should replace CV%. The information is easily stored as an assay error polynomial. The laboratory can serve the medical community better. There is no longer any need for LLOQ, a significant improvement. Regulatory agencies should implement this more informed policy.

  13. Improving multi-objective reservoir operation optimization with sensitivity-informed problem decomposition

    Science.gov (United States)

    Chu, J. G.; Zhang, C.; Fu, G. T.; Li, Y.; Zhou, H. C.

    2015-04-01

    This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce the computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed problem decomposition dramatically reduces the computational demands required for attaining high quality approximations of optimal tradeoff relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed problem decomposition and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform problem decomposition when solving the complex multi-objective reservoir operation problems.

  14. Optimizing Chinese character displays improves recognition and reading performance of simulated irregular phosphene maps.

    Science.gov (United States)

    Lu, Yanyu; Kan, Han; Liu, Jie; Wang, Jing; Tao, Chen; Chen, Yao; Ren, Qiushi; Hu, Jie; Chai, Xinyu

    2013-04-26

    A visual prosthesis may elicit an irregular phosphene map relative to a regular electrode array. This study used simulated irregular phosphene maps as a way of optimizing the display methods of Chinese characters (CCs) to improve recognition and reading performance. TWENTY SUBJECTS WITH NORMAL OR CORRECTED SIGHT PARTICIPATED IN TWO EXPERIMENTS (9 FEMALES, 11 MALES, 2030 YEARS OF AGE). EXPERIMENT 1: two character display methods were proposed: selecting phosphenes covered by character strokes on a simulated phosphene array (projection method) and finding the phosphene closest to the expected location in some range of an irregular phosphene array as a substitute (nearest neighbor search [NNS] method). The recognition accuracy of CCs was investigated using six levels for the coverage ratio of stroke and phosphene area and for search range, respectively, for two methods, for several irregularity levels. Experiment 2: reading accuracy (RA) and reading efficiency (RE) were measured using the regular array correspondence and NNS methods. EXPERIMENT 1: projection and NNS methods were significantly affected by coverage ratio or search range. NNS significantly improved CC recognition accuracy to the highest at 81.3 ± 2.7% and 59.1 ± 5.2%, respectively, for different irregularity levels, compared with the projection method. Experiment 2: RA and RE significantly decreased as the distortion level increased; NNS significantly improved RA (from approximately 40% to >80%) and RE (from approximately 13 char/min to >40 char/min) when reading more irregular paragraphs. The performance of CC recognition and paragraph reading when using an irregular phosphene array can be improved through optimizing the display method.

  15. Handling Practicalities in Agricultural Policy Optimization for Water Quality Improvements

    Science.gov (United States)

    Bilevel and multi-objective optimization methods are often useful to spatially target agri-environmental policy throughout a watershed. This type of problem is complex and is comprised of a number of practicalities: (i) a large number of decision variables, (ii) at least two inte...

  16. Improving Memory for Optimization and Learning in Dynamic Environments

    Science.gov (United States)

    2011-07-01

    Administration, 2004. [31] Dipankar Dasgupta and Douglas R. McGregor . Nonstationary function optimization using the structured genetic algorithm. In...implicit memories that use this concept of the dual include those by Gaspar and Collard [37] and Yang [104]. Dasgupta and McGregor created the

  17. Optimal spinneret size for improvement of fiber's mechanical property

    Directory of Open Access Journals (Sweden)

    Yang Zhanping

    2013-01-01

    Full Text Available The effect of spinneret size and place on diameter and tensile property of cellulose acetate fibers is studied, and a criterion for the maximal breaking energy is obtained, and the spinneret distribution can be optimized for each spinning condition.

  18. Strain improvement and optimization of the media composition of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-18

    Jul 18, 2008 ... All media were sterilized by autoclaving at 121oC for 15 min and the. pH was adjusted ... treated spores were diluted in sterile physiological saline, and 1 ml ..... Laccase production by Pleurotus ostreatus 1804: Optimization of.

  19. An Optimization Technique for Improved VoIP Performance over Wireless LAN

    Directory of Open Access Journals (Sweden)

    Tamal Chakraborty

    2012-03-01

    Full Text Available The performance of wireless LANs is greatly affected by pathloss, RF interference and other sources of signal attenuation, in addition to network congestion. The primary factors involved in effective real-time communication, namely delay and loss, must be within certain controlled limits in such a scenario. In this paper, we analyze the various factors driving IEEE 802.11b access points through extensive simulations and thereafter develop an optimization technique to configure the parameters of the access points. We simulate our test bed scenario and apply the developed algorithm. We then implement the configured parameters in our SIP enabled test bed to provide optimum Voice over IP (VoIP performance. Thereafter, we further analyze and optimize the parameters of the communicating nodes being realized through Xlite soft phones that enhance VoIP performance to a much better extent both for voice and video calls. Test bed results confirm an improvement from 22% packet loss to 3% considering both AP and node configurations together. Finally, we propose optimization algorithm for proper selection of threshold parameters in active queue management system. Results verify significant performance improvement in VoIP under congested scenarios. Simulation and measured results have also been included.

  20. Co-optimization of lithographic and patterning processes for improved EPE performance

    Science.gov (United States)

    Maslow, Mark J.; Timoshkov, Vadim; Kiers, Ton; Jee, Tae Kwon; de Loijer, Peter; Morikita, Shinya; Demand, Marc; Metz, Andrew W.; Okada, Soichiro; Kumar, Kaushik A.; Biesemans, Serge; Yaegashi, Hidetami; Di Lorenzo, Paolo; Bekaert, Joost P.; Mao, Ming; Beral, Christophe; Larivière, Stephane

    2017-03-01

    Complimentary lithography is already being used for advanced logic patterns. The tight pitches for 1D Metal layers are expected to be created using spacer based multiple patterning ArF-i exposures and the more complex cut/block patterns are made using EUV exposures. At the same time, control requirements of CDU, pattern shift and pitch-walk are approaching sub-nanometer levels to meet edge placement error (EPE) requirements. Local variability, such as Line Edge Roughness (LER), Local CDU, and Local Placement Error (LPE), are dominant factors in the total Edge Placement error budget. In the lithography process, improving the imaging contrast when printing the core pattern has been shown to improve the local variability. In the etch process, it has been shown that the fusion of atomic level etching and deposition can also improve these local variations. Co-optimization of lithography and etch processing is expected to further improve the performance over individual optimizations alone. To meet the scaling requirements and keep process complexity to a minimum, EUV is increasingly seen as the platform for delivering the exposures for both the grating and the cut/block patterns beyond N7. In this work, we evaluated the overlay and pattern fidelity of an EUV block printed in a negative tone resist on an ArF-i SAQP grating. High-order Overlay modeling and corrections during the exposure can reduce overlay error after development, a significant component of the total EPE. During etch, additional degrees of freedom are available to improve the pattern placement error in single layer processes. Process control of advanced pitch nanoscale-multi-patterning techniques as described above is exceedingly complicated in a high volume manufacturing environment. Incorporating potential patterning optimizations into both design and HVM controls for the lithography process is expected to bring a combined benefit over individual optimizations. In this work we will show the EPE

  1. Thermosensitive Hydrogel Mask Significantly Improves Skin Moisture and Skin Tone; Bilateral Clinical Trial

    Directory of Open Access Journals (Sweden)

    Anna Quattrone

    2017-06-01

    Full Text Available Objective: A temperature-sensitive state-changing hydrogel mask was used in this study. Once it comes into contact with the skin and reaches the body temperature, it uniformly and quickly releases the active compounds, which possess moisturizing, anti-oxidant, anti-inflammatory and regenerative properties. Methods: An open label clinical trial was conducted to evaluate the effects of the test product on skin hydration, skin tone and skin ageing. Subjects applied the product to one side of their face and underwent Corneometer® and Chromameter measurements, Visual assessment of facial skin ageing and facial photography. All assessments and Self-Perception Questionnaires (SPQ were performed at baseline, after the first application of the test product and after four applications. Results: After a single treatment we observed an increase in skin moisturisation, an improvement of skin tone/luminosity and a reduction in signs of ageing, all statistically significant. After four applications a further improvement in all measured parameters was recorded. These results were confirmed by the subjects’ own perceptions, as reported in the SPQ both after one and four applications. Conclusion: The hydrogel mask tested in this study is very effective in improving skin hydration, skin radiance and luminosity, in encouraging an even skin tone and in reducing skin pigmentation.

  2. E2F5 status significantly improves malignancy diagnosis of epithelial ovarian cancer

    KAUST Repository

    Kothandaraman, Narasimhan

    2010-02-24

    Background: Ovarian epithelial cancer (OEC) usually presents in the later stages of the disease. Factors, especially those associated with cell-cycle genes, affecting the genesis and tumour progression for ovarian cancer are largely unknown. We hypothesized that over-expressed transcription factors (TFs), as well as those that are driving the expression of the OEC over-expressed genes, could be the key for OEC genesis and potentially useful tissue and serum markers for malignancy associated with OEC.Methods: Using a combination of computational (selection of candidate TF markers and malignancy prediction) and experimental approaches (tissue microarray and western blotting on patient samples) we identified and evaluated E2F5 transcription factor involved in cell proliferation, as a promising candidate regulatory target in early stage disease. Our hypothesis was supported by our tissue array experiments that showed E2F5 expression only in OEC samples but not in normal and benign tissues, and by significantly positively biased expression in serum samples done using western blotting studies.Results: Analysis of clinical cases shows that of the E2F5 status is characteristic for a different population group than one covered by CA125, a conventional OEC biomarker. E2F5 used in different combinations with CA125 for distinguishing malignant cyst from benign cyst shows that the presence of CA125 or E2F5 increases sensitivity of OEC detection to 97.9% (an increase from 87.5% if only CA125 is used) and, more importantly, the presence of both CA125 and E2F5 increases specificity of OEC to 72.5% (an increase from 55% if only CA125 is used). This significantly improved accuracy suggests possibility of an improved diagnostics of OEC. Furthermore, detection of malignancy status in 86 cases (38 benign, 48 early and late OEC) shows that the use of E2F5 status in combination with other clinical characteristics allows for an improved detection of malignant cases with sensitivity

  3. Significant Improvements in the Practice Patterns of Adult Related Donor Care in US Transplantation Centers.

    Science.gov (United States)

    Anthias, Chloe; Shaw, Bronwen E; Kiefer, Deidre M; Liesveld, Jane L; Yared, Jean; Kamble, Rammurti T; D'Souza, Anita; Hematti, Peiman; Seftel, Matthew D; Norkin, Maxim; DeFilipp, Zachariah; Kasow, Kimberly A; Abidi, Muneer H; Savani, Bipin N; Shah, Nirali N; Anderlini, Paolo; Diaz, Miguel A; Malone, Adriana K; Halter, Joerg P; Lazarus, Hillard M; Logan, Brent R; Switzer, Galen E; Pulsipher, Michael A; Confer, Dennis L; O'Donnell, Paul V

    2016-03-01

    Recent investigations have found a higher incidence of adverse events associated with hematopoietic cell donation in related donors (RDs) who have morbidities that if present in an unrelated donor (UD) would preclude donation. In the UD setting, regulatory standards ensure independent assessment of donors, one of several crucial measures to safeguard donor health and safety. A survey conducted by the Center for International Blood and Marrow Transplant Research (CIBMTR) Donor Health and Safety Working Committee in 2007 reported a potential conflict of interest in >70% of US centers, where physicians had simultaneous responsibility for RDs and their recipients. Consequently, several international organizations have endeavored to improve practice through regulations and consensus recommendations. We hypothesized that the changes in the 2012 Foundation for the Accreditation of Cellular Therapy and the Joint Accreditation Committee-International Society for Cellular Therapy and European Society for Blood and Marrow Transplantation standards resulting from the CIBMTR study would have significantly impacted practice. Accordingly, we conducted a follow-up survey of US transplantation centers to assess practice changes since 2007, and to investigate additional areas where RD care was predicted to differ from UD care. A total of 73 centers (53%), performing 79% of RD transplantations in the United States, responded. Significant improvements were observed since the earlier survey; 62% centers now ensure separation of RD and recipient care (P < .0001). This study identifies several areas where RD management does not meet international donor care standards, however. Particular concerns include counseling and assessment of donors before HLA typing, with 61% centers first disclosing donor HLA results to an individual other than the donor, the use of unlicensed mobilization agents, and the absence of long-term donor follow-up. Recommendations for improvement are

  4. Significant improvements in the practice patterns of adult related donor care in US transplant centers

    Science.gov (United States)

    MBChB, Chloe Anthias; Shaw, Bronwen E; Kiefer, Deidre M; Liesveld, Jane L; Yared, Jean; Kambl, Rammurti T; D'Souza, Anita; Hematti, Peiman; Seftel, Matthew D; Norkin, Maxim; DeFilipp, Zachariah M; Kasow, Kimberly A; Abidi, Muneer H; Savani, Bipin N; Shah, Nirali N; Anderlini, Paolo; Diaz, Miguel A; Malone, Adriana K; Halter, Joerg P; Lazarus, Hillard M; Logan, Brent R; Switzer, Galen E; Pulsipher, Michael A; Confer, Dennis L; O'Donnell, Paul V

    2016-01-01

    Recent investigations have found a higher incidence of adverse events associated with hematopoietic cell donation in related donors (RDs) who have morbidities that if present in an unrelated donor (UD) would preclude donation. In the UD setting, regulatory standards ensure independent assessment of donors, one of several crucial measures to safeguard donor health and safety. A survey conducted by the Center for International Blood and Marrow Transplant Research (CIBMTR) Donor Health and Safety Working Committee in 2007 reported a potential conflict of interest in >70% US centers, where physicians had simultaneous responsibility for RDs and their recipients. Consequently, several international organizations have endeavored to improve practice through regulations and consensus recommendations. We hypothesized that the changes in the 2012 FACT-JACIE Standards, resulting from the CIBMTR study, will have significantly impacted practice. Accordingly, a follow-up survey of US transplant centers was conducted to assess practice changes since 2007, and investigate additional areas where RD care was predicted to differ from UD care. 73 centers (53%), performing 79% of US RD transplants responded. Significant improvements were observed since the earlier survey; 62% centers now ensure separation of RD and recipient care (P<0.0001). However, this study identifies several areas where RD management does not meet international donor care standards. Particular concerns include counseling and assessment of donors before HLA typing, with 61% centers first disclosing donor HLA results to an individual other than the donor, the use of unlicensed mobilization agents, and the absence of long-term donor follow-up. Recommendations for improvement are described. PMID:26597080

  5. An improved adaptive sampling and experiment design method for aerodynamic optimization

    Institute of Scientific and Technical Information of China (English)

    Huang Jiangtao; Gao Zhenghong; Zhou Zhu; Zhao Ke

    2015-01-01

    Experiment design method is a key to construct a highly reliable surrogate model for numerical optimization in large-scale project. Within the method, the experimental design criterion directly affects the accuracy of the surrogate model and the optimization efficient. According to the shortcomings of the traditional experimental design, an improved adaptive sampling method is pro-posed in this paper. The surrogate model is firstly constructed by basic sparse samples. Then the supplementary sampling position is detected according to the specified criteria, which introduces the energy function and curvature sampling criteria based on radial basis function (RBF) network. Sampling detection criteria considers both the uniformity of sample distribution and the description of hypersurface curvature so as to significantly improve the prediction accuracy of the surrogate model with much less samples. For the surrogate model constructed with sparse samples, the sample uniformity is an important factor to the interpolation accuracy in the initial stage of adaptive sam-pling and surrogate model training. Along with the improvement of uniformity, the curvature description of objective function surface gradually becomes more important. In consideration of these issues, crowdness enhance function and root mean square error (RMSE) feedback function are introduced in C criterion expression. Thus, a new sampling method called RMSE and crowd-ness enhance (RCE) adaptive sampling is established. The validity of RCE adaptive sampling method is studied through typical test function firstly and then the airfoil/wing aerodynamic opti-mization design problem, which has high-dimensional design space. The results show that RCE adaptive sampling method not only reduces the requirement for the number of samples, but also effectively improves the prediction accuracy of the surrogate model, which has a broad prospects for applications.

  6. Optimal Cooperative Relaying Schemes for Improving Wireless Physical Layer Security

    CERN Document Server

    Li, Jiangyuan; Weber, Steven

    2010-01-01

    We consider a cooperative wireless network in the presence of one of more eavesdroppers, and exploit node cooperation for achieving physical (PHY) layer based security. Two different cooperation schemes are considered. In the first scheme, cooperating nodes retransmit a weighted version of the source signal in a decode-and-forward (DF) fashion. In the second scheme, while the source is transmitting, cooperating nodes transmit weighted noise to confound the eavesdropper (cooperative jamming (CJ)). We investigate two objectives, i.e., maximization of achievable secrecy rate subject to a total power constraint, and minimization of total power transmit power under a secrecy rate constraint. For the first design objective with a single eavesdropper we obtain expressions for optimal weights under the DF protocol in closed form, and give an algorithm that converges to the optimal solution for the CJ scheme; while for multiple eavesdroppers we give an algorithm for the solution using the DF protocol that is guarantee...

  7. Optimal design of SAW-based gyroscope to improve sensitivity

    Science.gov (United States)

    Oh, Haekwan; Yang, Sangsik; Lee, Keekeun

    2010-02-01

    A surface acoustic wave (SAW)-based gyroscope was developed on a piezoelectric substrate. The developed gyroscope consists of two SAW oscillators, metallic dots, and absorber. Coupling of mode (COM) modeling was conducted to determine the optimal device parameters prior to fabrication. Depending on the angular velocity, the difference of the oscillation frequency was modulated. The obtained sensitivity was approximately 52.35 Hz/deg.s at an angular rate range of 0~1000 deg/s.

  8. The Improvement of Quantum Genetic Algorithm and Its Application on Function Optimization

    Directory of Open Access Journals (Sweden)

    Huaixiao Wang

    2013-01-01

    Full Text Available To accelerate the evolutionary process and increase the probability to find the optimal solution, the following methods are proposed to improve the conventional quantum genetic algorithm: an improved method to determine the rotating angle, the self-adaptive rotating angle strategy, adding the quantum mutation operation and quantum disaster operation. The efficiency and accuracy to search the optimal solution of the algorithm are greatly improved. Simulation test shows that the improved quantum genetic algorithm is more effective than the conventional quantum genetic algorithm to solve some optimization problems.

  9. On optimally partitioning a text to improve its compression

    CERN Document Server

    Ferragina, Paolo; Venturini, Rossano

    2009-01-01

    In this paper we investigate the problem of partitioning an input string T in such a way that compressing individually its parts via a base-compressor C gets a compressed output that is shorter than applying C over the entire T at once. This problem was introduced in the context of table compression, and then further elaborated and extended to strings and trees. Unfortunately, the literature offers poor solutions: namely, we know either a cubic-time algorithm for computing the optimal partition based on dynamic programming, or few heuristics that do not guarantee any bounds on the efficacy of their computed partition, or algorithms that are efficient but work in some specific scenarios (such as the Burrows-Wheeler Transform) and achieve compression performance that might be worse than the optimal-partitioning by a $\\Omega(\\sqrt{\\log n})$ factor. Therefore, computing efficiently the optimal solution is still open. In this paper we provide the first algorithm which is guaranteed to compute in $O(n \\log_{1+\\eps}...

  10. Improved mine blast algorithm for optimal cost design of water distribution systems

    Science.gov (United States)

    Sadollah, Ali; Guen Yoo, Do; Kim, Joong Hoon

    2015-12-01

    The design of water distribution systems is a large class of combinatorial, nonlinear optimization problems with complex constraints such as conservation of mass and energy equations. Since feasible solutions are often extremely complex, traditional optimization techniques are insufficient. Recently, metaheuristic algorithms have been applied to this class of problems because they are highly efficient. In this article, a recently developed optimizer called the mine blast algorithm (MBA) is considered. The MBA is improved and coupled with the hydraulic simulator EPANET to find the optimal cost design for water distribution systems. The performance of the improved mine blast algorithm (IMBA) is demonstrated using the well-known Hanoi, New York tunnels and Balerma benchmark networks. Optimization results obtained using IMBA are compared to those using MBA and other optimizers in terms of their minimum construction costs and convergence rates. For the complex Balerma network, IMBA offers the cheapest network design compared to other optimization algorithms.

  11. Improving agricultural water productivity: Between optimism and caution

    NARCIS (Netherlands)

    Molden, D.J.; Oweis, T.; Steduto, P.; Bindraban, P.S.; Hanjra, A.; Kijne, J.

    2010-01-01

    In its broadest sense, water productivity (WP) is the net return for a unit of water used. Improvement of water productivity aims at producing more food, income, better livelihoods and ecosystem services with less water. There is considerable scope for improving water productivity of crop, livestock

  12. A multi-objective improved teaching-learning based optimization algorithm for unconstrained and constrained optimization problems

    Directory of Open Access Journals (Sweden)

    R. Venkata Rao

    2014-01-01

    Full Text Available The present work proposes a multi-objective improved teaching-learning based optimization (MO-ITLBO algorithm for unconstrained and constrained multi-objective function optimization. The MO-ITLBO algorithm is the improved version of basic teaching-learning based optimization (TLBO algorithm adapted for multi-objective problems. The basic TLBO algorithm is improved to enhance its exploration and exploitation capacities by introducing the concept of number of teachers, adaptive teaching factor, tutorial training and self-motivated learning. The MO-ITLBO algorithm uses a grid-based approach to adaptively assess the non-dominated solutions (i.e. Pareto front maintained in an external archive. The performance of the MO-ITLBO algorithm is assessed by implementing it on unconstrained and constrained test problems proposed for the Congress on Evolutionary Computation 2009 (CEC 2009 competition. The performance assessment is done by using the inverted generational distance (IGD measure. The IGD measures obtained by using the MO-ITLBO algorithm are compared with the IGD measures of the other state-of-the-art algorithms available in the literature. Finally, Lexicographic ordering is used to assess the overall performance of competitive algorithms. Results have shown that the proposed MO-ITLBO algorithm has obtained the 1st rank in the optimization of unconstrained test functions and the 3rd rank in the optimization of constrained test functions.

  13. Significant Improvement of Organic Thin-Film Transistor Mobility Utilizing an Organic Heterojunction Buffer Layer

    Institute of Scientific and Technical Information of China (English)

    PAN Feng; QIAN Xian-Rui; HUANG Li-Zhen; WANG Hai-Bo; YAN Dong-Hang

    2011-01-01

    High-mobility vanadyl phthalocyanine (VOPc)/5,5″′-bis(4-fluorophenyl)-2,2′:5′,2″:5″,2″′-quaterthiophene (F2-P4T) thin-film transistors are demonstrated by employing a copper hexadecafluorophthalocyanine (F16 CuPc)/copper phthalocyanine (CuPc) heterojunction unit,which are fabricated at different substrate temperatures,as a buffer layer. The highest mobility of 4.08cm2/Vs is achieved using a F16CuPc/CuPc organic heterojunction buffer layer fabricated at high substrate temperature.Compared with the random small grain-like morphology of the room-temperature buffer layer,the high-temperature organic heterojunction presents a large-sized fiber-like film morphology,resulting in an enhanced conductivity.Thus the contact resistance of the transistor is significantly reduced and an obvious improvement in device mobility is obtained.

  14. Improved Glowworm Swarm Optimization Algorithm for Multilevel Color Image Thresholding Problem

    Directory of Open Access Journals (Sweden)

    Lifang He

    2016-01-01

    Full Text Available The thresholding process finds the proper threshold values by optimizing a criterion, which can be considered as a constrained optimization problem. The computation time of traditional thresholding techniques will increase dramatically for multilevel thresholding. To greatly overcome this problem, swarm intelligence algorithm is widely used to search optimal thresholds. In this paper, an improved glowworm swarm optimization (IGSO algorithm has been presented to find the optimal multilevel thresholds of color image based on the between-class variance and minimum cross entropy (MCE. The proposed methods are examined on standard set of color test images by using various numbers of threshold values. The results are then compared with those of basic glowworm swarm optimization, adaptive particle swarm optimization (APSO, and self-adaptive differential evolution (SaDE. The simulation results show that the proposed method can find the optimal thresholds accurately and efficiently and is an effective multilevel thresholding method for color image segmentation.

  15. pEPito: a significantly improved non-viral episomal expression vector for mammalian cells

    Directory of Open Access Journals (Sweden)

    Ogris Manfred

    2010-03-01

    Full Text Available Abstract Background The episomal replication of the prototype vector pEPI-1 depends on a transcription unit starting from the constitutively expressed Cytomegalovirus immediate early promoter (CMV-IEP and directed into a 2000 bp long matrix attachment region sequence (MARS derived from the human β-interferon gene. The original pEPI-1 vector contains two mammalian transcription units and a total of 305 CpG islands, which are located predominantly within the vector elements necessary for bacterial propagation and known to be counterproductive for persistent long-term transgene expression. Results Here, we report the development of a novel vector pEPito, which is derived from the pEPI-1 plasmid replicon but has considerably improved efficacy both in vitro and in vivo. The pEPito vector is significantly reduced in size, contains only one transcription unit and 60% less CpG motives in comparison to pEPI-1. It exhibits major advantages compared to the original pEPI-1 plasmid, including higher transgene expression levels and increased colony-forming efficiencies in vitro, as well as more persistent transgene expression profiles in vivo. The performance of pEPito-based vectors was further improved by replacing the CMV-IEP with the human CMV enhancer/human elongation factor 1 alpha promoter (hCMV/EF1P element that is known to be less affected by epigenetic silencing events. Conclusions The novel vector pEPito can be considered suitable as an improved vector for biotechnological applications in vitro and for non-viral gene delivery in vivo.

  16. Optimization of the reflux ratio for a stage distillation column based on an improved particle swarm algorithm

    DEFF Research Database (Denmark)

    Ren, Jingzheng; Tan, Shiyu; Dong, Lichun

    2010-01-01

    the searching ability of basic particle swarm algorithm significantly. An example of utilizing the improved algorithm to solve the mathematical model was demonstrated; the result showed that it is efficient and convenient to optimize the reflux ratio for a distillation column by using the mathematical model......A mathematical model relating operation profits with reflux ratio of a stage distillation column was established. In order to optimize the reflux ratio by solving the nonlinear objective function, an improved particle swarm algorithm was developed and has been proved to be able to enhance...

  17. An On-Chip RBC Deformability Checker Significantly Improves Velocity-Deformation Correlation

    Directory of Open Access Journals (Sweden)

    Chia-Hung Dylan Tsai

    2016-10-01

    Full Text Available An on-chip deformability checker is proposed to improve the velocity–deformation correlation for red blood cell (RBC evaluation. RBC deformability has been found related to human diseases, and can be evaluated based on RBC velocity through a microfluidic constriction as in conventional approaches. The correlation between transit velocity and amount of deformation provides statistical information of RBC deformability. However, such correlations are usually only moderate, or even weak, in practical evaluations due to limited range of RBC deformation. To solve this issue, we implemented three constrictions of different width in the proposed checker, so that three different deformation regions can be applied to RBCs. By considering cell responses from the three regions as a whole, we practically extend the range of cell deformation in the evaluation, and could resolve the issue about the limited range of RBC deformation. RBCs from five volunteer subjects were tested using the proposed checker. The results show that the correlation between cell deformation and transit velocity is significantly improved by the proposed deformability checker. The absolute values of the correlation coefficients are increased from an average of 0.54 to 0.92. The effects of cell size, shape and orientation to the evaluation are discussed according to the experimental results. The proposed checker is expected to be useful for RBC evaluation in medical practices.

  18. The Sensitivity of Adolescent School-Based Hearing Screens Is Significantly Improved by Adding High Frequencies.

    Science.gov (United States)

    Sekhar, Deepa L; Zalewski, Thomas R; Beiler, Jessica S; Czarnecki, Beth; Barr, Ashley L; King, Tonya S; Paul, Ian M

    2016-12-01

    High frequency hearing loss (HFHL), often related to hazardous noise, affects one in six U.S. adolescents. Yet, only 20 states include school-based hearing screens for adolescents. Only six states test multiple high frequencies. Study objectives were to (1) compare the sensitivity of state school-based hearing screens for adolescents to gold standard sound-treated booth testing and (2) consider the effect of adding multiple high frequencies and two-step screening on sensitivity/specificity. Of 134 eleventh-grade participants (2013-2014), 43 of the 134 (32%) did not pass sound-treated booth testing, and 27 of the 43 (63%) had HFHL. Sensitivity/specificity of the most common protocol (1,000, 2,000, 4,000 Hz at 20 dB HL) for these hearing losses was 25.6% (95% confidence interval [CI] = [13.5, 41.2]) and 85.7% (95% CI [76.8, 92.2]), respectively. A protocol including 500, 1,000, 2,000, 4,000, 6,000 Hz at 20 dB HL significantly improved sensitivity to 76.7% (95% CI [61.4, 88.2]), p < .001. Two-step screening maintained specificity (84.6%, 95% CI [75.5, 91.3]). Adolescent school-based hearing screen sensitivity improves with high frequencies.

  19. Significantly improved cyclability of lithium manganese oxide under elevated temperature by an easily oxidized electrolyte additive

    Science.gov (United States)

    Zhu, Yunmin; Rong, Haibo; Mai, Shaowei; Luo, Xueyi; Li, Xiaoping; Li, Weishan

    2015-12-01

    Spinel lithium manganese oxide, LiMn2O4, is a promising cathode for lithium ion battery in large-scale applications, because it possesses many advantages compared with currently used layered lithium cobalt oxide (LiCoO2) and olivine phosphate (LiFePO4), including naturally abundant resource, environmental friendliness and high and long work potential plateau. Its poor cyclability under high temperature, however, limits its application. In this work, we report a significant cyclability improvement of LiMn2O4 under elevated temperature by using dimethyl phenylphonite (DMPP) as an electrolyte additive. Charge/discharge tests demonstrate that the application of 0.5 wt.% DMPP yields a capacity retention improvement from 16% to 82% for LiMn2O4 after 200 cycles under 55 °C at 1 C (1C = 148 mAh g-1) between 3 and 4.5 V. Electrochemical and physical characterizations indicate that DMPP is electrochemically oxidized at the potential lower than that for lithium extraction, forming a protective cathode interphase on LiMn2O4, which suppresses the electrolyte decomposition and prevents LiMn2O4 from crystal destruction.

  20. AN IMPROVED ANT COLONY ALGORITHM IN CONTINUOUS OPTIMIZATION

    Institute of Scientific and Technical Information of China (English)

    Ling CHEN; Jie SHEN; Ling QIN; Hongjian CHEN

    2003-01-01

    A modified ant colony algorithm for solving optimization problem with continuous parameters is presented. In the method, groups of candidate values of the components are constructed, and each value in the group has its trail information. In each iteration of the ant colony algorithm, the method first chooses initial values of the components using the trail information. Then GA operations of crossover and mutation can determine the values of the components in the solution. Our experimental results on the problem of nonlinear programming show that our method has a much higher convergence speed and stability than those of simulated annealing (SA) and GA.

  1. Significant improvement in statin adherence and cholesterol levels after acute myocardial infarction

    DEFF Research Database (Denmark)

    Brogaard, Hilde Vaiva Tonstad; Køhn, Morten Ganderup; Berget, Oline Sofie

    2012-01-01

    Not all patients recovering from acute myocardial infarction (AMI) are optimally treated with statin, and their adherence to statin treatment may be inadequate. We set out to describe changes in statin treatment adherence and cholesterol values over time.......Not all patients recovering from acute myocardial infarction (AMI) are optimally treated with statin, and their adherence to statin treatment may be inadequate. We set out to describe changes in statin treatment adherence and cholesterol values over time....

  2. Tailored deep brain stimulation optimization for improved airway protective outcomes in Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Michelle S. Troche

    2016-09-01

    Full Text Available There is no consensus regarding the effects of deep brain stimulation (DBS surgery on swallowing outcomes in Parkinson's disease (PD. No prospective studies have compared airway protective outcomes following DBS to the subthalamic nucleus (STN versus globus pallidus interna (GPi. A recent retrospective study described swallowing outcomes pre- and post-STN vs. GPi DBS in a cohort of 34 patients with PD. The results revealed that the patients who received GPi DBS maintained their swallowing function post-DBS, while those in the STN group significantly worsened in swallowing safety. As DBS surgery becomes a common management option in PD it is important to understand the impact of DBS on airway protective outcomes; especially given that aspiration pneumonia is the leading cause of death in this population. We present a case report in which optimizing DBS settings with the goal of improving laryngeal function resulted in immediate improvements to swallowing safety.

  3. Determine Optimal Stimulus Amplitude for Using Vestibular Stochastic Stimulation to Improve Balance Function

    Science.gov (United States)

    Goel, R.; Kofman, I.; DeDios, Y. E.; Jeevarajan, J.; Stepanyan, V.; Nair, M.; Congdon, S.; Fregia, M.; Cohen, H.; Bloomberg, J.J.; Mulavara, A.P.

    2015-01-01

    Sensorimotor changes such as postural and gait instabilities can affect the functional performance of astronauts when they transition across different gravity environments. We are developing a method, based on stochastic resonance (SR), to enhance information transfer by applying non-zero levels of external noise on the vestibular system (vestibular stochastic resonance, VSR). Our previous work has shown the advantageous effects of VSR in a balance task of standing on an unstable surface [1]. This technique to improve detection of vestibular signals uses a stimulus delivery system that provides imperceptibly low levels of white noise-based binaural bipolar electrical stimulation of the vestibular system. The goal of this project is to determine optimal levels of stimulation for SR applications by using a defined vestibular threshold of motion detection. A series of experiments were carried out to determine a robust paradigm to identify a vestibular threshold that can then be used to recommend optimal stimulation levels for sensorimotor adaptability (SA) training applications customized to each crewmember. The amplitude of stimulation to be used in the VSR application has varied across studies in the literature such as 60% of nociceptive stimulus thresholds [2]. We compared subjects' perceptual threshold with that obtained from two measures of body sway. Each test session was 463s long and consisted of several 15s long sinusoidal stimuli, at different current amplitudes (0-2 mA), interspersed with 20-20.5s periods of no stimulation. Subjects sat on a chair with their eyes closed and had to report their perception of motion through a joystick. A force plate underneath the chair recorded medio-lateral shear forces and roll moments. Comparison of threshold of motion detection obtained from joystick data versus body sway suggests that perceptual thresholds were significantly lower. In the balance task, subjects stood on an unstable surface and had to maintain balance

  4. An Improved Genetic Algorithm for Allocation Optimization of Distribution Centers

    Institute of Scientific and Technical Information of China (English)

    钱晶; 庞小红; 吴智铭

    2004-01-01

    This paper introduced an integrated allocation model for distribution centers (DCs). The facility cost, inventory cost, transportation cost and service quality were considered in the model. An improved genetic algorithm (IGA) was proposed to solve the problem. The improvement of IGA is based on the idea of adjusting crossover probability and mutation probability. The IGA is supplied by heuristic rules too. The simulation results show that the IGA is better than the standard GA(SGA) in search efficiency and equality.

  5. Fabrication of CoZn alloy nanowire arrays: Significant improvement in magnetic properties by annealing process

    Energy Technology Data Exchange (ETDEWEB)

    Koohbor, M. [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Soltanian, S., E-mail: s.soltanian@gmail.com [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Department of Electrical and Computer Engineering, University of British Columbia, Vancouver (Canada); Najafi, M. [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Department of Physics, Hamadan University of Technology, Hamadan (Iran, Islamic Republic of); Servati, P. [Department of Electrical and Computer Engineering, University of British Columbia, Vancouver (Canada)

    2012-01-05

    Highlights: Black-Right-Pointing-Pointer Increasing the Zn concentration changes the structure of NWs from hcp to amorphous. Black-Right-Pointing-Pointer Increasing the Zn concentration significantly reduces the Hc value of NWs. Black-Right-Pointing-Pointer Magnetic properties of CoZn NWs can be significantly enhanced by appropriate annealing. Black-Right-Pointing-Pointer The pH of electrolyte has no significant effect on the properties of the NW arrays. Black-Right-Pointing-Pointer Deposition frequency has considerable effects on the magnetic properties of NWs. - Abstract: Highly ordered arrays of Co{sub 1-x}Zn{sub x} (0 {<=} x {<=} 0.74) nanowires (NWs) with diameters of {approx}35 nm and high length-to-diameter ratios (up to 150) were fabricated by co-electrodeposition of Co and Zn into pores of anodized aluminum oxide (AAO) templates. The Co and Zn contents of the NWs were adjusted by varying the ratio of Zn and Co ion concentrations in the electrolyte. The effect of the Zn content, electrodeposition conditions (frequency and pH) and annealing on the structural and magnetic properties (e.g., coercivity (Hc) and squareness (Sq)) of NW arrays were investigated using X-ray diffraction (XRD), scanning electron microscopy, electron diffraction, and alternating gradient force magnetometer (AGFM). XRD patterns reveal that an increase in the concentration of Zn ions of the electrolyte forces the hcp crystal structure of Co NWs to change into an amorphous phase, resulting in a significant reduction in Hc. It was found that the magnetic properties of NWs can be significantly improved by appropriate annealing process. The highest values for Hc (2050 Oe) and Sq (0.98) were obtained for NWs electrodeposited using 0.95/0.05 Co:Zn concentrations at 200 Hz and annealed at 575 Degree-Sign C. While the pH of electrolyte is found to have no significant effect on the structural and magnetic properties of the NW arrays, the electrodeposition frequency has considerable effects on

  6. Optimization of permeability for quality improvement by using factorial design

    Science.gov (United States)

    Said, Rahaini Mohd; Miswan, Nor Hamizah; Juan, Ng Shu; Hussin, Nor Hafizah; Ahmad, Aminah; Kamal, Mohamad Ridzuan Mohamad

    2017-05-01

    Sand castings are used worldwide by the manufacturing process in Metal Casting Industry, whereby the green sand are the commonly used sand mould type in the industry of sand casting. The defects on the surface of casting product is one of the problems in the industry of sand casting. The problems that relates to the defect composition of green sand are such as blowholes, pinholes shrinkage and porosity. Our objective is to optimize the best composition of green sand in order to minimize the occurrence of defects. Sand specimen of difference parameters (Bentonite, Green Sand, Cold dust and water) were design and prepared to undergo permeability test. The 24 factorial design experiment with four factors at difference composition were runs, and the total of 16 runs experiment were conducted. The developed models based on the experimental design necessary models were obtained. The model with a high coefficient of determination (R2=0.9841) and model for predicted and actual fitted well with the experimental data. Using the Analysis of Design Expert software, we identified that bentonite and water are the main interaction effect in the experiments. The optimal settings for green sand composition are 100g silica sand, 21g bentonite, 6.5 g water and 6g coal dust. This composition gives an effect of permeability number 598.3GP.

  7. Optimized, Unequal Pulse Spacing in Multiple Echo Sequences Improves Refocusing

    CERN Document Server

    Jenista, Elizabeth; Branca, Rosa; Warren, Warren

    2009-01-01

    A recent quantum computing paper (G. S. Uhrig, Phys Rev Lett 98 100504 (2007)) analytically derived optimal pulse spacings for a multiple spin echo sequence designed to remove decoherence in a two level system coupled to a bath. The spacings in what has been called a UDD sequence differ dramatically from the conventional, equal pulse spacing of a Carr-Purcell-Meiboom-Gill (CPMG) multiple spin echo sequence. The UDD sequence was derived for a model that is unrelated to magnetic resonance, but was recently shown theoretically to be more general. Here we show that the UDD sequence has theoretical advantages for magnetic resonance imaging of structured materials such as tissue, where diffusion in compartmentalized and microstructured environments leads to fluctuating fields on a range of different timescales. We also show experimentally, both in excised tissue and in a live mouse tumor model, that optimal UDD sequences produce different T2-weighted contrast than do CPMG sequences with the same number of pulses an...

  8. An optimal parametric design to improve chip cooling

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Y.-S. [Department of Engineering and System Science, National Tsing Hua University, Taiwan (China); Fu, H.-H. [Department of Business Administration, Shu-Te University, Taiwan (China); Hung, T.-C. [Department of Mechanical and Automation Engineering, I-Shou University, Kaohsiung County 840, Taiwan (China)]. E-mail: tchung@isu.edu.tw; Pei, B.-S. [Department of Engineering and System Science, National Tsing Hua University, Taiwan (China)

    2007-08-15

    The thermal problems of most electronic components have been solved in recent years by installing various cooling equipments. The passive cooling, which has no need of the fluid-driving devices, can be more reliable and achieved with less cost. In this paper, the Taguchi's method is applied on the optimization of the passive cooling for electronic systems, and a representative CFD (computational fluid dynamic) model is selectively implemented for statistical analysis. The selected parameters in this study are the power density, mother board orientation, chip geometry, opening between chips and the flow pattern. The optimal combination for thermal cooling is obtained by using a two-level statistical approach. Analysis results indicate that about 50% of the effort in performing experiments and simulations can be saved. Further, the results confirmed that the most important parameters affecting the thermal behaviors are the openings in the mother board, power density, and the flow pattern in sequence. Finally, the concept of opening increases the reliability, reduces the manufacturing cost, and simplifies the assembly procedures.

  9. Exchange inlet optimization by genetic algorithm for improved RBCC performance

    Science.gov (United States)

    Chorkawy, G.; Etele, J.

    2017-09-01

    A genetic algorithm based on real parameter representation using a variable selection pressure and variable probability of mutation is used to optimize an annular air breathing rocket inlet called the Exchange Inlet. A rapid and accurate design method which provides estimates for air breathing, mixing, and isentropic flow performance is used as the engine of the optimization routine. Comparison to detailed numerical simulations show that the design method yields desired exit Mach numbers to within approximately 1% over 75% of the annular exit area and predicts entrained air massflows to between 1% and 9% of numerically simulated values depending on the flight condition. Optimum designs are shown to be obtained within approximately 8000 fitness function evaluations in a search space on the order of 106. The method is also shown to be able to identify beneficial values for particular alleles when they exist while showing the ability to handle cases where physical and aphysical designs co-exist at particular values of a subset of alleles within a gene. For an air breathing engine based on a hydrogen fuelled rocket an exchange inlet is designed which yields a predicted air entrainment ratio within 95% of the theoretical maximum.

  10. Improved SpikeProp for Using Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Falah Y. H. Ahmed

    2013-01-01

    Full Text Available A spiking neurons network encodes information in the timing of individual spike times. A novel supervised learning rule for SpikeProp is derived to overcome the discontinuities introduced by the spiking thresholding. This algorithm is based on an error-backpropagation learning rule suited for supervised learning of spiking neurons that use exact spike time coding. The SpikeProp is able to demonstrate the spiking neurons that can perform complex nonlinear classification in fast temporal coding. This study proposes enhancements of SpikeProp learning algorithm for supervised training of spiking networks which can deal with complex patterns. The proposed methods include the SpikeProp particle swarm optimization (PSO and angle driven dependency learning rate. These methods are presented to SpikeProp network for multilayer learning enhancement and weights optimization. Input and output patterns are encoded as spike trains of precisely timed spikes, and the network learns to transform the input trains into target output trains. With these enhancements, our proposed methods outperformed other conventional neural network architectures.

  11. Aerodynamic Improvements of an Empty Timber Truck can Have the Potential of Significantly Reducing Fuel Consumption

    Science.gov (United States)

    Andersson, Magnus; Marashi, Seyedeh Sepideh; Karlsson, Matts

    2012-11-01

    In the present study, aerodynamic drag (AD) has been estimated for an empty and a fully loaded conceptual timber truck (TT) using Computational Fluid Dynamics (CFD). The increasing fuel prices have challenged heavy duty vehicle (HDV) manufactures to strive for better fuel economy, by e.g. utilizing drag reducing external devices. Despite this knowledge, the TT fleets seem to be left in the dark. Like HDV aerodynamics, similarities can be observed as a large low pressure wake is formed behind the tractor (unloaded) and downstream of the trailer (full load) thus generating AD. As TTs travel half the time without any cargo, focus on drag reduction is important. The full scaled TTs where simulated using the realizable k-epsilon model with grid adaption techniques for mesh independence. Our results indicate that a loaded TT reduces the AD significantly as both wake size and turbulence kinetic energy are lowered. In contrast to HDV the unloaded TTs have a much larger design space available for possible drag reducing devices, e.g. plastic wrapping and/or flaps. This conceptual CFD study has given an indication of the large AD difference between the unloaded and fully loaded TT, showing the potential for significant AD improvements.

  12. Significant improvement in one-dimensional cursor control using Laplacian electroencephalography over electroencephalography

    Science.gov (United States)

    Boudria, Yacine; Feltane, Amal; Besio, Walter

    2014-06-01

    Objective. Brain-computer interfaces (BCIs) based on electroencephalography (EEG) have been shown to accurately detect mental activities, but the acquisition of high levels of control require extensive user training. Furthermore, EEG has low signal-to-noise ratio and low spatial resolution. The objective of the present study was to compare the accuracy between two types of BCIs during the first recording session. EEG and tripolar concentric ring electrode (TCRE) EEG (tEEG) brain signals were recorded and used to control one-dimensional cursor movements. Approach. Eight human subjects were asked to imagine either ‘left’ or ‘right’ hand movement during one recording session to control the computer cursor using TCRE and disc electrodes. Main results. The obtained results show a significant improvement in accuracies using TCREs (44%-100%) compared to disc electrodes (30%-86%). Significance. This study developed the first tEEG-based BCI system for real-time one-dimensional cursor movements and showed high accuracies with little training.

  13. Significant improvement of survival by intrasplenic hepatocyte transplantation in totally hepatectomized rats.

    Science.gov (United States)

    Vogels, B A; Maas, M A; Bosma, A; Chamuleau, R A

    1996-01-01

    The effect of intrasplenic hepatocyte transplantation (HTX) was studied in an experimental model of acute liver failure in rats with chronic liver atrophy. Rats underwent a portacaval shunt operation on Day -14 to induce liver atrophy, and underwent total hepatectomy on Day 0 as a start of acute liver failure. Intrasplenic hepatocyte or sham transplantation was performed on Day -7,-3, or -1 (n = 4 to 6 per group). During the period following hepatectomy, mean arterial blood pressure was maintained above 80 mm Hg and hypoglycaemia was prevented. Severity of hepatic encephalopathy was assessed by clinical grading and EEG spectral analysis, together with determination of blood ammonia and plasma amino acid concentrations, and "survival" time. Histological examination of the spleen and lungs was performed after sacrifice. Intrasplenic hepatocyte transplantation resulted in a significant improvement in clinical grading in all transplanted groups (p 0.05), HTX at Day -3: 19.7 +/- 3.7 h vs. 6.5 +/- 0.3 h (p ammonia concentrations after total hepatectomy (p spleens after sacrifice showed clusters of hepatocytes in the red pulp. Hepatocytes present in the spleen for 3 and 7 days showed bile accumulation and spots of beginning necrosis. The present data show that in a hard model of complete liver failure in portacaval shunted rats, intrasplenic hepatocyte transplantation is able to prolong "survival" time significantly 2- to 3-fold. The relevance of this observation for human application is discussed.

  14. Construction of Pancreatic Cancer Classifier Based on SVM Optimized by Improved FOA

    Directory of Open Access Journals (Sweden)

    Huiyan Jiang

    2015-01-01

    Full Text Available A novel method is proposed to establish the pancreatic cancer classifier. Firstly, the concept of quantum and fruit fly optimal algorithm (FOA are introduced, respectively. Then FOA is improved by quantum coding and quantum operation, and a new smell concentration determination function is defined. Finally, the improved FOA is used to optimize the parameters of support vector machine (SVM and the classifier is established by optimized SVM. In order to verify the effectiveness of the proposed method, SVM and other classification methods have been chosen as the comparing methods. The experimental results show that the proposed method can improve the classifier performance and cost less time.

  15. Construction of Pancreatic Cancer Classifier Based on SVM Optimized by Improved FOA.

    Science.gov (United States)

    Jiang, Huiyan; Zhao, Di; Zheng, Ruiping; Ma, Xiaoqi

    2015-01-01

    A novel method is proposed to establish the pancreatic cancer classifier. Firstly, the concept of quantum and fruit fly optimal algorithm (FOA) are introduced, respectively. Then FOA is improved by quantum coding and quantum operation, and a new smell concentration determination function is defined. Finally, the improved FOA is used to optimize the parameters of support vector machine (SVM) and the classifier is established by optimized SVM. In order to verify the effectiveness of the proposed method, SVM and other classification methods have been chosen as the comparing methods. The experimental results show that the proposed method can improve the classifier performance and cost less time.

  16. AN IMPROVED OPTIMAL CHANNEL SHORTENING ALGORITHM FOR DMT MODULATION SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In Discrete Multi-Tone (DMT) modulation systems, the well-known technique to overcome the Inter-Carrier Interference (ICI)/Inter-Symbol Interference (ISI) caused by the inadequate Cyclic Prefix (CP) length is to use a Time-Domain Equalizer (TDE) at the receiver front-end. An algorithm used to calculate the coefficients of the optimal shortening Time Domain Equalizer (TDE) was given by Melsa. However, this al gorithm requires that the length of the TDE must be smaller than or equal to the memory length of the target impulse response. This paper modifies this algorithm and makes it not only fit for calculating the coefficients of the TDE with arbitrary length, but also have a much less computational time.

  17. Quantifying dynamic sensitivity of optimization algorithm parameters to improve hydrological model calibration

    Science.gov (United States)

    Qi, Wei; Zhang, Chi; Fu, Guangtao; Zhou, Huicheng

    2016-02-01

    It is widely recognized that optimization algorithm parameters have significant impacts on algorithm performance, but quantifying the influence is very complex and difficult due to high computational demands and dynamic nature of search parameters. The overall aim of this paper is to develop a global sensitivity analysis based framework to dynamically quantify the individual and interactive influence of algorithm parameters on algorithm performance. A variance decomposition sensitivity analysis method, Analysis of Variance (ANOVA), is used for sensitivity quantification, because it is capable of handling small samples and more computationally efficient compared with other approaches. The Shuffled Complex Evolution method developed at the University of Arizona algorithm (SCE-UA) is selected as an optimization algorithm for investigation, and two criteria, i.e., convergence speed and success rate, are used to measure the performance of SCE-UA. Results show the proposed framework can effectively reveal the dynamic sensitivity of algorithm parameters in the search processes, including individual influences of parameters and their interactive impacts. Interactions between algorithm parameters have significant impacts on SCE-UA performance, which has not been reported in previous research. The proposed framework provides a means to understand the dynamics of algorithm parameter influence, and highlights the significance of considering interactive parameter influence to improve algorithm performance in the search processes.

  18. Intestinal-borne dermatoses significantly improved by oral application of Escherichia coli Nissle 1917

    Science.gov (United States)

    Manzhalii, Elina; Hornuss, Daniel; Stremmel, Wolfgang

    2016-01-01

    AIM: To evaluate the effect of oral Escherichia coli (E. coli) Nissle application on the outcome of intestinal-borne dermatoses. METHODS: In a randomized, controlled, non-blinded prospective clinical trial 82 patients with intestinal-borne facial dermatoses characterized by an erythematous papular-pustular rash were screened. At the initiation visit 37 patients entered the experimental arm and 20 patients constituted the control arm. All 57 patients were treated with a vegetarian diet and conventional topical therapy of the dermatoses with ointments containing tetracycline, steroids and retinoids. In the experimental arm patients received a one month therapy with oral E. coli Nissle at a maintenance dose of 2 capsules daily. The experimental group was compared to a non-treatment group only receiving the diet and topical therapy. The primary outcome parameter was improvement of the dermatoses, secondary parameters included life quality and adverse events. In addition the immunological reaction profile (IgA, interleucin-8 and interferon-α) was determined. Furthermore the changes of stool consistency and the microbiota composition over the time of intervention were recorded. RESULTS: Eighty-nine percent of the patients with acne, papular-pustular rosacea and seborrhoic dermatitis responded to E. coli Nissle therapy with significant amelioration or complete recovery in contrast to 56% in the control arm (P 107 CFU/g stool) was observed in 79% and 63% of the patients, respectively (P 0.05). Accordingly, stool consistency, color and smell normalized in the E. coli Nissle treated patients. CONCLUSION: E. coli Nissle protects the mucus barrier by overgrowth of a favorable gut microbiota with less immunoreactive potential which finally leads to clinical improvement of intestinal borne dermatoses. PMID:27340358

  19. FES Training in Aging: interim results show statistically significant improvements in mobility and muscle fiber size

    Directory of Open Access Journals (Sweden)

    Helmut Kern

    2012-03-01

    Full Text Available Aging is a multifactorial process that is characterized by decline in muscle mass and performance. Several factors, including reduced exercise, poor nutrition and modified hormonal metabolism, are responsible for changes in the rates of protein synthesis and degradation that drive skeletal muscle mass reduction with a consequent decline of force generation and mobility functional performances. Seniors with normal life style were enrolled: two groups in Vienna (n=32 and two groups in Bratislava: (n=19. All subjects were healthy and declared not to have any specific physical/disease problems. The two Vienna groups of seniors exercised for 10 weeks with two different types of training (leg press at the hospital or home-based functional electrical stimulation, h-b FES. Demografic data (age, height and weight were recorded before and after the training period and before and after the training period the patients were submitted to mobility functional analyses and muscle biopsies. The mobility functional analyses were: 1. gait speed (10m test fastest speed, in m/s; 2. time which the subject needed to rise from a chair for five times (5x Chair-Rise, in s; 3. Timed –Up-Go- Test, in s; 4. Stair-Test, in s; 5. isometric measurement of quadriceps force (Torque/kg, in Nm/kg; and 6. Dynamic Balance in mm. Preliminary analyses of muscle biopsies from quadriceps in some of the Vienna and Bratislava patients present morphometric results consistent with their functional behaviors. The statistically significant improvements in functional testings here reported demonstrates the effectiveness of h-b FES, and strongly support h-b FES, as a safe home-based method to improve contractility and performances of ageing muscles.

  20. Cyclosporin A significantly improves preeclampsia signs and suppresses inflammation in a rat model.

    Science.gov (United States)

    Hu, Bihui; Yang, Jinying; Huang, Qian; Bao, Junjie; Brennecke, Shaun Patrick; Liu, Huishu

    2016-05-01

    Preeclampsia is associated with an increased inflammatory response. Immune suppression might be an effective treatment. The aim of this study was to examine whether Cyclosporin A (CsA), an immunosuppressant, improves clinical characteristics of preeclampsia and suppresses inflammation in a lipopolysaccharide (LPS) induced preeclampsia rat model. Pregnant rats were randomly divided into 4 groups: group 1 (PE) rats each received LPS via tail vein on gestational day (GD) 14; group 2 (PE+CsA5) rats were pretreated with LPS (1.0 μg/kg) on GD 14 and were then treated with CsA (5mg/kg, ip) on GDs 16, 17 and 18; group 3 (PE+CsA10) rats were pretreated with LPS (1.0 μg/kg) on GD 14 and were then treated with CsA (10mg/kg, ip) on GDs 16, 17 and 18; group 4 (pregnant control, PC) rats were treated with the vehicle (saline) used for groups 1, 2 and 3. Systolic blood pressure, urinary albumin, biometric parameters and the levels of serum cytokines were measured on day 20. CsA treatment significantly reduced LPS-induced systolic blood pressure and the mean 24-h urinary albumin excretion. Pro-inflammatory cytokines IL-6, IL-17, IFN-γ and TNF-α were increased in the LPS treatment group but were reduced in (LPS+CsA) group (PCyclosporine A improved preeclampsia signs and attenuated inflammatory responses in the LPS induced preeclampsia rat model which suggests that immunosuppressant might be an alternative management option for preeclampsia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Global optimal path planning for mobile robot based on improved Dijkstra algorithm and ant system algorithm

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A novel method of global optimal path planning for mobile robot was proposed based on the improved Dijkstra algorithm and ant system algorithm. This method includes three steps: the first step is adopting the MAKLINK graph theory to establish the free space model of the mobile robot, the second step is adopting the improved Dijkstra algorithm to find out a sub-optimal collision-free path, and the third step is using the ant system algorithm to adjust and optimize the location of the sub-optimal path so as to generate the global optimal path for the mobile robot. The computer simulation experiment was carried out and the results show that this method is correct and effective. The comparison of the results confirms that the proposed method is better than the hybrid genetic algorithm in the global optimal path planning.

  2. Improving Punctuality and Transfer Reliability by Railway Timetable Optimization

    NARCIS (Netherlands)

    Goverde, R.M.P.

    1999-01-01

    The Dutch railway network is operated close to capacity with the current safety system. This leaves little space for control by process operators by which a delayed train can cause severe delay propagation. The NS currently invest a large amount in punctuality improvement of the railway operations.

  3. An Improved Optimization Method for the Relevance Voxel Machine

    DEFF Research Database (Denmark)

    Ganz, Melanie; Sabuncu, M. R.; Van Leemput, Koen

    2013-01-01

    In this paper, we will re-visit the Relevance Voxel Machine (RVoxM), a recently developed sparse Bayesian framework used for predicting biological markers, e.g., presence of disease, from high-dimensional image data, e.g., brain MRI volumes. The proposed improvement, called IRVoxM, mitigates the ...

  4. Improving digital image watermarking by means of optimal channel selection

    NARCIS (Netherlands)

    Huynh-The, Thien; Banos, Oresti; Lee, Sungyoung; Yoon, Yongik; Le-Tien, Thuong

    2016-01-01

    Supporting safe and resilient authentication and integrity of digital images is of critical importance in a time of enormous creation and sharing of these contents. This paper presents an improved digital image watermarking model based on a coefficient quantization technique that intelligently encod

  5. AN IMPROVED MULTIVARIATE LOSS FUNCTION APPROACH TO OPTIMIZATION

    Institute of Scientific and Technical Information of China (English)

    Yizhong MA; Fengyu ZHAO

    2004-01-01

    The basic purpose of a quality loss function is to evaluate a loss to customers in a quantitative manner. Although there are several multivariate loss functions that have been proposed and studied in the literature, it has room for improvement. A good multivariate loss function should represent an appropriate compromise in terms of both process economics and the correlation structure among various responses. More important, it should be easily understood and implemented in practice.According to this criterion, we first introduce a pragmatic dimensionless multivariate loss function proposed by Artiles-Leon, then we improve the multivariate loss function in two respects: one is making it suitable for all three types of quality characteristics; the other is considering correlation structure among the various responses, which makes the improved multivariate loss function more adequate in the real world. On the bases of these, an example from industrial practice is provided to compare our improved method with other methods, and last, some reviews are presented in conclusion.

  6. Improving Punctuality and Transfer Reliability by Railway Timetable Optimization

    NARCIS (Netherlands)

    Goverde, R.M.P.

    1999-01-01

    The Dutch railway network is operated close to capacity with the current safety system. This leaves little space for control by process operators by which a delayed train can cause severe delay propagation. The NS currently invest a large amount in punctuality improvement of the railway operations.

  7. A small change in the design of a slit bioaerosol impactor significantly improves its collection characteristics.

    Science.gov (United States)

    Grinshpun, Sergey A; Adhikari, Atin; Cho, Seung-Hyun; Kim, Ki-Youn; Lee, Taekhee; Reponen, Tiina

    2007-08-01

    While several methods are available for bioaerosol monitoring, impaction remains the most common one, particularly for collecting fungal spores. Earlier studies have shown that the collection efficiency of many conventional single-stage bioaerosol impactors falls below 50% for spores with an aerodynamic diameter between 1.7 and 2.5 microm because their cut-off size is 2.5 microm or greater. The cut-off size reduction is primarily done by substantially increasing the sampling flow rate or decreasing the impaction jet size, W, to a fraction of a millimetre, with both measures often impractical to implement. Some success has recently been reported on the utilization of an ultra-low jet-to-plate distance, S (S/W bioaerosol impactors, Allergenco-D and Air-O-Cell, which feature the same jet dimensions and flow rate but have some design configuration differences that were initially thought to be of low significance. The collection efficiency and the spore deposit characteristics were determined in the laboratory using real-time aerosol spectrometry and different microscopic enumeration methods as the test impactors were challenged with the non-biological polydisperse NaCl aerosol and the aerosolized fungal spores of Cladosporium cladosporioides, Aspergillus versicolor, and Penicillium melinii. The tests showed that a relatively small reduction in the jet-to-plate distance of a single-stage, single-nozzle impactor with a tapered inlet nozzle, combined with adding a straight section of sufficient length, can significantly decrease the cut-off size to the level that is sufficient to efficiently collect spores of all fungal species. Furthermore, it appears that the slit jet design may improve the application of partial spore counting methodologies with respect to those applied to circular deposits. Data from a demonstration field study, conducted with the two samplers in environments containing a variety of fungal species, supported the laboratory findings.

  8. Significantly improving trace thallium removal from surface waters during coagulation enhanced by nanosized manganese dioxide.

    Science.gov (United States)

    Huangfu, Xiaoliu; Ma, Chengxue; Ma, Jun; He, Qiang; Yang, Chun; Jiang, Jin; Wang, Yaan; Wu, Zhengsong

    2017-02-01

    Thallium (Tl) is an element of high toxicity and significant accumulation in human body. There is an urgent need for the development of appropriate strategies for trace Tl removal in drinking water treatment plants. In this study, the efficiency and mechanism of trace Tl (0.5 μg/L) removal by conventional coagulation enhanced by nanosized manganese dioxide (nMnO2) were explored in simulated water and two representative surface waters (a river water and a reservoir water obtained from Northeast China). Experimental results showed that nMnO2 significantly improve Tl(I) removal from selected waters. The removal efficiency was dramatically higher in the simulated water, demonstrating by less than 0.1 μg/L Tl residual. The enhancement of trace Tl removal in the surface waters decreased to a certain extent. Both adjusting water pH to alkaline condition and preoxidation of Tl(I) to Tl(III) benefit trace Tl removal from surface waters. Data also indicated that competitive cation of Ca(2+) decreased the efficiency of trace Tl removal, resulting from the reduction of Tl adsorption on nMnO2. Humic acid could largely low Tl removal efficiency during nMnO2 enhanced coagulation processes. Trace elemental Tl firstly adsorbed on nMnO2 and then removed accompanying with nMnO2 settling. The information obtained in the present study may provide a potential strategy for drinking water treatment plants threatened by trace Tl.

  9. Optimizing in vitro culture conditions leads to a significantly shorter production time of human dermo-epidermal skin substitutes.

    Science.gov (United States)

    Pontiggia, Luca; Klar, Agnieszka; Böttcher-Haberzeth, Sophie; Biedermann, Thomas; Meuli, Martin; Reichmann, Ernst

    2013-03-01

    Autologous dermo-epidermal skin substitutes (DESS) generated in vitro represent a promising therapeutic means to treat full-thickness skin defects in clinical practice. A serious drawback with regard to acute patients is the relatively long production time of 3-4 weeks. With this experimental study we aimed to decrease the production time of DESS without compromising their quality. Two in vitro steps of DESS construction were varied: the pre-cultivation time of fibroblasts in hydrogels (1, 3, and 6 days), and the culture time of keratinocytes (3, 6, and 12 days) before transplantation of DESS on nude rats. Additionally, the impact of the air-liquid interface culture during 3 days before transplantation was investigated. 3 weeks after transplantation, the macroscopic appearance was evaluated and histological sections were produced to analyze structure and thickness of epidermis and dermis, the stratification of the epidermis, and the presence of a basal lamina. Optimal DESS formation was obtained with a fibroblast pre-cultivation time of 6 days. The minimal culture time of keratinocytes on hydrogels was also 6 days. The air-liquid interface culture did not improve graft quality. By optimizing our in vitro culture conditions, it was possible to very substantially reduce the production time for DESS from 21 to 12 days. However, pre-cultivation of fibroblasts in the dermal equivalent and proliferation of keratinocytes before transplantation remain crucial for an equilibrated maturation of the epidermis and cannot be completely skipped.

  10. Optimal Stimulus Amplitude for Vestibular Stochastic Stimulation to Improve Sensorimotor Function

    Science.gov (United States)

    Goel, R.; Kofman, I.; DeDios, Y. E.; Jeevarajan, J.; Stepanyan, V.; Nair, M.; Congdon, S.; Fregia, M.; Cohen, H.; Bloomberg, J. J.; Mulavara, A. P.

    2014-01-01

    standard deviation of the noise level in the baseline measurement) was detected by the sensors. The percentage time at each stimulation level for motion detection was normalized with respect to the largest value and a logistic regression curve fit was applied to these data. The threshold was defined at the 50% probability of motion detection. Comparison of threshold of motion detection obtained from joystick data versus body sway suggests that perceptual thresholds were significantly lower, and were not impacted by system noise. Further, in order to determine optimal stimulation amplitude to improve balance, two sets of experiments were carried out. In the first set of experiments, all subjects received the same level of stimuli and the intensity of optimal performance was projected back on subjects' vestibular threshold curve. In the second set of experiments, on different subjects, stimulation was administered from 20-400% of subjects' vestibular threshold obtained from joystick data. Preliminary results of our study show that, in general, using stimulation amplitudes at 40-60% of perceptual motion threshold improved balance performance significantly compared to control (no stimulation). The amplitude of vestibular stimulation that improved balance function was predominantly in the range of +/- 100 to +/- 400 micro A. We hypothesize that VSR stimulation will act synergistically with sensorimotor adaptability (SA) training to improve adaptability by increasing utilization of vestibular information and therefore will help us to optimize and personalize a SA countermeasure prescription. This combination will help to significantly reduce the number of days required to recover functional performance to preflight levels after long-duration spaceflight.

  11. Significantly improved photocurrent response of ZnS-reduced graphene oxide composites

    Energy Technology Data Exchange (ETDEWEB)

    Sookhakian, M., E-mail: m.sokhakian@gmail.com [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Amin, Y.M. [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Zakaria, R. [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Photonics Research Centre, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Basirun, W.J. [Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Institute of Nanotechnology & Catalysis Research (NanoCat), University Malaya, Kuala Lumpur 50603 (Malaysia); Mahmoudian, M.R. [Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Nasiri-Tabrizi, B.; Baradaran, S. [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Azarang, Majid [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia)

    2015-05-25

    Highlights: • ZnS/reduced graphene oxide nanoparticles by hydrothermal method. • ZnS nanoparticles in a gelatin medium without agglomeration. • Support of ZnS shows efficient photocurrent response. • The fabricated solar cell electrode improved in the presence of reduced graphene oxide. - Abstract: ZnS-nanoparticles (NPs) reduced graphene oxide (rGO) composites with a high degree of crystallinity and high dispersity were successfully synthesized via a facile solvothermal method in the gelatin medium, during which the formation of ZnS NPs, reduction of graphene oxide and loading of ZnS NPs into the rGO surface occur simultaneously. Gelatin, as a natural capping agent, plays a significant role in controlling the degree of dispersion and coverage of ZnS NPs. The effect of rGO on the crystalline structure and optical properties of ZnS NPs were determined via X-ray diffraction, UV–visible diffused reflectance spectroscopy and photoluminescence spectroscopy. The ZnS–rGO composites exhibit excellent potential for photocurrent generation compared with pure ZnS NPs under visible light irradiation, provided that efficient photoinduced charge separation and transportation can be achieved at the interface. The maximum photocurrent response was obtained for ZnS–rGO composite with a 3% mass fraction of rGO, which is 2 times that achieved on pure ZnS NPs.

  12. Activation of Big Grain1 significantly improves grain size by regulating auxin transport in rice.

    Science.gov (United States)

    Liu, Linchuan; Tong, Hongning; Xiao, Yunhua; Che, Ronghui; Xu, Fan; Hu, Bin; Liang, Chengzhen; Chu, Jinfang; Li, Jiayang; Chu, Chengcai

    2015-09-01

    Grain size is one of the key factors determining grain yield. However, it remains largely unknown how grain size is regulated by developmental signals. Here, we report the identification and characterization of a dominant mutant big grain1 (Bg1-D) that shows an extra-large grain phenotype from our rice T-DNA insertion population. Overexpression of BG1 leads to significantly increased grain size, and the severe lines exhibit obviously perturbed gravitropism. In addition, the mutant has increased sensitivities to both auxin and N-1-naphthylphthalamic acid, an auxin transport inhibitor, whereas knockdown of BG1 results in decreased sensitivities and smaller grains. Moreover, BG1 is specifically induced by auxin treatment, preferentially expresses in the vascular tissue of culms and young panicles, and encodes a novel membrane-localized protein, strongly suggesting its role in regulating auxin transport. Consistent with this finding, the mutant has increased auxin basipetal transport and altered auxin distribution, whereas the knockdown plants have decreased auxin transport. Manipulation of BG1 in both rice and Arabidopsis can enhance plant biomass, seed weight, and yield. Taking these data together, we identify a novel positive regulator of auxin response and transport in a crop plant and demonstrate its role in regulating grain size, thus illuminating a new strategy to improve plant productivity.

  13. Optimization and improvement of FOA corner cube algorithm

    Science.gov (United States)

    McClay, Wilbert A., III; Awwal, Abdul A. S.; Burkhart, Scott C.; Candy, James V.

    2004-11-01

    Alignment of laser beams based on video images is a crucial task necessary to automate operation of the 192 beams at the National Ignition Facility (NIF). The final optics assembly (FOA) is the optical element that aligns the beam into the target chamber. This work presents an algorithm for determining the position of a corner cube alignment image in the final optics assembly. The improved algorithm was compared to the existing FOA algorithm on 900 noise-simulated images. While the existing FOA algorithm based on correlation with a synthetic template has a radial standard deviation of 1 pixel, the new algorithm based on classical matched filtering (CMF) and polynomial fit to the correlation peak improves the radial standard deviation performance to less than 0.3 pixels. In the new algorithm the templates are designed from real data stored during a year of actual operation.

  14. Optimization and Improvement of FOA Corner Cube Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    McClay, W A; Awwal, A S; Burkhart, S C; Candy, J V

    2004-10-01

    Alignment of laser beams based on video images is a crucial task necessary to automate operation of the 192 beams at the National Ignition Facility (NIF). The final optics assembly (FOA) is the optical element that aligns the beam into the target chamber. This work presents an algorithm for determining the position of a corner cube alignment image in the final optics assembly. The improved algorithm was compared to the existing FOA algorithm on 900 noise-simulated images. While the existing FOA algorithm based on correlation with a synthetic template has a radial standard deviation of 1 pixel, the new algorithm based on classical matched filtering (CMF) and polynomial fit to the correlation peak improves the radial standard deviation performance to less than 0.3 pixels. In the new algorithm the templates are designed from real data stored during a year of actual operation.

  15. Combining optimization methods with response spectra curve-fitting toward improved damping ratio estimation

    Science.gov (United States)

    Brewick, Patrick T.; Smyth, Andrew W.

    2016-12-01

    The authors have previously shown that many traditional approaches to operational modal analysis (OMA) struggle to properly identify the modal damping ratios for bridges under traffic loading due to the interference caused by the driving frequencies of the traffic loads. This paper presents a novel methodology for modal parameter estimation in OMA that overcomes the problems presented by driving frequencies and significantly improves the damping estimates. This methodology is based on finding the power spectral density (PSD) of a given modal coordinate, and then dividing the modal PSD into separate regions, left- and right-side spectra. The modal coordinates were found using a blind source separation (BSS) algorithm and a curve-fitting technique was developed that uses optimization to find the modal parameters that best fit each side spectra of the PSD. Specifically, a pattern-search optimization method was combined with a clustering analysis algorithm and together they were employed in a series of stages in order to improve the estimates of the modal damping ratios. This method was used to estimate the damping ratios from a simulated bridge model subjected to moving traffic loads. The results of this method were compared to other established OMA methods, such as Frequency Domain Decomposition (FDD) and BSS methods, and they were found to be more accurate and more reliable, even for modes that had their PSDs distorted or altered by driving frequencies.

  16. Algorithmic and technical improvements: Optimal solutions to the (Generalized) Multi-Weber Problem

    NARCIS (Netherlands)

    K.E. Rosing (Kenneth); B. Harris (Britton)

    1992-01-01

    textabstractRosing has recently demonstrated a new method for obtaining optimal solutions to the (Generalized) Multi-Weber Problem and proved the optimality of the results. The method develops all convex hulls and then covers the destinations with disjoint convex hulls. This paper seeks to improve i

  17. A Cyclo-dissipativity Condition for Power Factor Improvement in Nonsinusoidal Systems with Significant Source Impedance

    NARCIS (Netherlands)

    del Puerto Flores, Dunstano; Scherpen, Jacquelien M.A.; Ortega, Romeo

    2010-01-01

    Recently, in [1] it has been established that the classical problem in electrical engineering of optimizing energy transfer from an alternating current (ac) source to a load with non-sinusoidal source (but periodic) voltage is equivalent to imposing the property of cyclo-dissipativity to the source

  18. An Improved Search Algorithm for Optimal Multiple-Sequence Alignment

    CERN Document Server

    Schroedl, S

    2011-01-01

    Multiple sequence alignment (MSA) is a ubiquitous problem in computational biology. Although it is NP-hard to find an optimal solution for an arbitrary number of sequences, due to the importance of this problem researchers are trying to push the limits of exact algorithms further. Since MSA can be cast as a classical path finding problem, it is attracting a growing number of AI researchers interested in heuristic search algorithms as a challenge with actual practical relevance. In this paper, we first review two previous, complementary lines of research. Based on Hirschbergs algorithm, Dynamic Programming needs O(kN^(k-1)) space to store both the search frontier and the nodes needed to reconstruct the solution path, for k sequences of length N. Best first search, on the other hand, has the advantage of bounding the search space that has to be explored using a heuristic. However, it is necessary to maintain all explored nodes up to the final solution in order to prevent the search from re-expanding them at hig...

  19. An Improved Chaos Genetic Algorithm for T-Shaped MIMO Radar Antenna Array Optimization

    Directory of Open Access Journals (Sweden)

    Xin Fu

    2014-01-01

    Full Text Available In view of the fact that the traditional genetic algorithm easily falls into local optimum in the late iterations, an improved chaos genetic algorithm employed chaos theory and genetic algorithm is presented to optimize the low side-lobe for T-shaped MIMO radar antenna array. The novel two-dimension Cat chaotic map has been put forward to produce its initial population, improving the diversity of individuals. The improved Tent map is presented for groups of individuals of a generation with chaos disturbance. Improved chaotic genetic algorithm optimization model is established. The algorithm presented in this paper not only improved the search precision, but also avoids effectively the problem of local convergence and prematurity. For MIMO radar, the improved chaos genetic algorithm proposed in this paper obtains lower side-lobe level through optimizing the exciting current amplitude. Simulation results show that the algorithm is feasible and effective. Its performance is superior to the traditional genetic algorithm.

  20. Signal-To Ratio Improvement in NMR via Receiver Hardware Optimization.

    Science.gov (United States)

    Duensing, George Randall

    The goal of this research was to increase available signal-to-noise ratio (SNR) in magnetic resonance imaging (MRI) by applying specific knowledge of the imaging system to improve receiver probes (coils) and receiving hardware. A brief history of improvements in MRI receiver and coil design is presented, including the transition from large linear volume coils to local surface coils and quadrature volume coils. Then quadrature surface coils are introduced and finally multi-coil arrays with independent acquisition systems. The research covers improvements in these areas and begins with a surface coil which is adjustable in size to optimize performance given the region of interest. By careful design of trombone-like coil elements, physical adjustment can be made without electrical adjustment. Second, new understanding of noise correlation and crosstalk between coils is developed and applied to multi-coil arrays. This provides the ability to increase available SNR for such systems. Third, a method for optimally combining multiple coils in a transverse (extending perpendicular to the static magnetic field) array into a single channel by proper signal combination is presented. This method is termed generalized quadrature because of the similarity of the method to standard quadrature combination, but with freedom in weighting and phasing in the combination process. Fourth, several methods of manipulating the multiple signals from an array to allow separation after acquisition are presented. These methods require new hardware demands but allow significant improvements in SNR for either transverse or longitudinal arrays. Fifth, several novel design methods are demonstrated, including an algorithm for impedance matching, a generalized quadrature combination method, transmission synchronized rf shielding and a bird-cage surface coil. Finally, the potential future applications and benefits of this research are presented.

  1. Significant improvement in dynamic visual acuity after cataract surgery: a promising potential parameter for functional vision.

    Directory of Open Access Journals (Sweden)

    Mingxin Ao

    Full Text Available PURPOSE: Dynamic visual acuity (DVA is a relatively independent parameter for evaluating the ability to distinguish details of a moving target. The present study has been designed to discuss the extent to which age-related cataract impacts DVA in elderly individuals and to determine whether it could be restored after bilateral phacoemulsification combined with intraocular lens implantation surgery. METHODS: Twenty-six elderly cataract patients scheduled for binocular cataract surgery and 30 elderly volunteers without cataract were enrolled in the study. DVA at 15, 30, 60 and 90 degree per second (dps was assessed, and velocity-dependent visual acuity decreases between consecutive speed levels were calculated. RESULTS: Compared with the control group, the patient group exhibited significantly worse DVA performance at all speed levels (p<0.001, and the decreases in velocity-dependent visual acuity were more serious in the patient group at the intervals of 0-15 dps (p<0.001, 15-30 dps (p = 0.007 and 30-60 dps (p = 0.008. Postoperatively, DVA performance at every speed level in the patient group clearly improved (p<0.001 and recovered to levels compatible to the control group. The decrease in visual acuity with increasing speed was less pronounced than during the preoperative phase (p0-15 dps = 0.001, p15-30 dps<0.001 and p30-60 dps = 0.001 and became similar to that of the control group. The postoperative visual benefit regarding DVA was more pronounced than the improvement in static visual acuity (p15 dps = 0.001 and p<0.001 at 30 dps, 60 dps and 90 dps. CONCLUSIONS: The impact of age-related cataract on DVA was more severe than its effects on static visual acuity. After cataract surgery, not only static vision of the patients was restored markedly, but also the dynamic vision. DVA could be an important adjunct to the current evaluation system of functional vision, thereby meriting additional attention in clinical assessment.

  2. Improved energy efficiency and optimization of microclimate in buildings

    Directory of Open Access Journals (Sweden)

    Trifunovič Dragišić Vesna

    2016-01-01

    Full Text Available Nowadays it is possible to reduce energy consumption without losing comfort as a result of using efficient energy saving technologies and advanced environment control methods for buildings. One of the measures to improve energy performance of buildings can be installation of decentralized air intake and exhaust mechanical ventilation systems with plate heat exchangers in apartments making it possible to «return» up to 85% of thermal energy. The article deals with the decentralized system controlled ventilation with heat recovery and alternative solutions heating supply air in residential buildings.

  3. Optimizing insulin pump therapy: a quality improvement project.

    Science.gov (United States)

    Meade, Lisa T; Rushton, Wanda E

    2013-01-01

    The purpose of the study was to assess insulin pump use and provide ongoing education. A quality improvement project using a pump assessment questionnaire was implemented at an endocrinology office in the southeastern United States. The questionnaire was designed to evaluate all aspects of insulin pump therapy, including pump operations, infusion set failure, management of acute complications, and usage of advanced device features. Eighty-nine patients (80% with type 1 diabetes and 20% with type 2 diabetes) completed the questionnaire at the endocrinology practice. A certified diabetes educator reviewed the questions with each patient, identifying deficiencies and training opportunities. The most common areas of deficiency identified after implementation of the assessment form included the following: expired or no basal insulin prescription in the event of pump failure or removal, no mupirocin (Bactroban®, GlaxoSmithKline, Research Triangle Park, North Carolina) prescription for suspected site infections, lack of insulin syringe if pump stopped working, failure to check urine ketones, no antiemetic prescription for sick day intervention, using manual bolus instead of bolus calculator, and lack of in-date glucagon kit. Use of a pump assessment questionnaire allows for focused discussion concerning patient behaviors related to pump operations, troubleshooting, and self-management. Incorporating use of a pump assessment questionnaire into routine practice may result in improved patient education and avoidance of adverse events specific to insulin pump therapy.

  4. Optimization of regional navigation satellite constellation by improved NSGA-II algorithm

    Science.gov (United States)

    Chang, Hui; Hu, Xiulin; Zhang, Yunyu; Zeng, Yujiang; Wang, Ying

    2009-12-01

    In this paper, the non-dominated sorting genetic algorithm II (NSGA-II) based on the concept of Pareto optimal is improved. A new algorithm with lower O(MNlogN) computational complexity to construct non-dominated set replaces the NSGA-II original fast non-dominated sorting algorithm with O(MN2) com-putational complexity. The new algorithm improves operating efficiency of NSGA-II significantly. Based on the combination of the improved NSGA-II algorithm and regional navigation satellite constellation design, a new idea to design regional navigation satellite constellation is proposed in this paper. The new idea is implemented by Satellite Tool Kits (STK) and Matlab: the improved NSGA-II algorithm is implemented by Matlab and the calculation of the objective function values is implemented by STK. STK/Connect interface is used to integrate STK and Matlab into one simulation. Simulation results show that new idea has some advantages over the traditional methods, being more efficient, more flexible and more comprehensive.

  5. The optimal code searching method with an improved criterion of coded exposure for remote sensing image restoration

    Science.gov (United States)

    He, Lirong; Cui, Guangmang; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2015-03-01

    Coded exposure photography makes the motion de-blurring a well-posed problem. The integration pattern of light is modulated using the method of coded exposure by opening and closing the shutter within the exposure time, changing the traditional shutter frequency spectrum into a wider frequency band in order to preserve more image information in frequency domain. The searching method of optimal code is significant for coded exposure. In this paper, an improved criterion of the optimal code searching is proposed by analyzing relationship between code length and the number of ones in the code, considering the noise effect on code selection with the affine noise model. Then the optimal code is obtained utilizing the method of genetic searching algorithm based on the proposed selection criterion. Experimental results show that the time consuming of searching optimal code decreases with the presented method. The restoration image is obtained with better subjective experience and superior objective evaluation values.

  6. Heat storage in forest biomass significantly improves energy balance closure particularly during stable conditions

    Directory of Open Access Journals (Sweden)

    A. Lindroth

    2009-08-01

    Full Text Available Temperature measurements in trunks and branches in a mature ca. 100 years-old mixed pine and spruce forest in central Sweden were used to estimate the heat storage in the tree biomass. The estimated heat flux in the sample trees and data on biomass distributions were used to scale up to stand level biomass heat fluxes. The rate of change of sensible and latent heat storage in the air layer below the level of the flux measurements was estimated from air temperature and humidity profile measurements and soil heat flux was estimated from heat flux plates and soil temperature measurements. The fluxes of sensible and latent heat from the forest were measured with an eddy covariance system in a tower. The analysis was made for a two-month period in summer of 1995. The tree biomass heat flux was the largest of the estimated storage components and varied between 40 and −35 W m−2 on summer days with nice weather. Averaged over two months the diurnal maximum of total heat storage was 45 W m−2 and the minimum was −35 W m−2. The soil heat flux and the sensible heat storage in air were out of phase with the biomass flux and they reached maximum values that were about 75% of the maximum of the tree biomass heat storage. The energy balance closure improved significantly when the total heat storage was added to the turbulent fluxes. The slope of a regression line with sum of fluxes and storage as independent and net radiation as dependent variable, increased from 0.86 to 0.95 for half-hourly data and the scatter was also reduced. The most significant finding was, however, that during nights with strongly stable conditions when the sensible heat flux dropped to nearly zero, the total storage matched the net radiation nearly perfectly. Another interesting result was that the mean energy imbalance started to increase when the Richardson number became more negative than ca. −0.1. In fact, the largest energy deficit

  7. Using gas modifiers to significantly improve sensitivity and selectivity in a cylindrical FAIMS device.

    Science.gov (United States)

    Purves, Randy W; Ozog, Allison R; Ambrose, Stephen J; Prasad, Satendra; Belford, Michael; Dunyach, Jean-Jacques

    2014-07-01

    Recent reports describing enhanced performance when using gas additives in a DMS device (planar electrodes) have indicated that comparable benefits are not attainable using FAIMS (cylindrical electrodes), owing to the non-homogeneous electric fields within the analyzer region. In this study, a FAIMS system (having cylindrical electrodes) was modified to allow for controlled delivery of gas additives. An experiment was carried out that illustrates the important distinction between gas modifiers present as unregulated contaminants and modifiers added in a controlled manner. The effect of contamination was simulated by adjusting the ESI needle position to promote incomplete desolvation, thereby permitting ESI solvent vapor into the FAIMS analyzer region, causing signal instability and irreproducible CV values. However, by actively controlling the delivery of the gas modifier, reproducible CV spectra were obtained. The effects of adding different gas modifiers were examined using 15 positive ions having mass-to-charge (m/z) values between 90 and 734. Significant improvements in peak capacity and increases in ion transmission were readily attained by adding acetonitrile vapor, even at trace levels (≤0.1%). Increases in signal intensity were greatest for the low m/z ions; for the six lowest molecular weight species, signal intensities increased by ∼10- to over 100-fold compared with using nitrogen without gas additives, resulting in equivalent or better signal intensities compared with ESI without FAIMS. These results confirm that analytical benefits derived from the addition of gas modifiers reported with a uniform electric field (DMS) also are observed using a non-homogenous electric field (FAIMS) in the analyser region.

  8. Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions.

    Science.gov (United States)

    Hengl, Tomislav; Heuvelink, Gerard B M; Kempen, Bas; Leenaars, Johan G B; Walsh, Markus G; Shepherd, Keith D; Sila, Andrew; MacMillan, Robert A; Mendes de Jesus, Jorge; Tamene, Lulseged; Tondoh, Jérôme E

    2015-01-01

    80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008-2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management--organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange capacity, total nitrogen, exchangeable acidity, Al content and exchangeable bases (Ca, K, Mg, Na). We specifically investigate differences between two predictive approaches: random forests and linear regression. Results of 5-fold cross-validation demonstrate that the random forests algorithm consistently outperforms the linear regression algorithm, with average decreases of 15-75% in Root Mean Squared Error (RMSE) across soil properties and depths. Fitting and running random forests models takes an order of magnitude more time and the modelling success is sensitive to artifacts in the input data, but as long as quality-controlled point data are provided, an increase in soil mapping accuracy can be expected. Results also indicate that globally predicted soil classes (USDA Soil Taxonomy, especially Alfisols and Mollisols) help improve continental scale soil property mapping, and are among the most important predictors. This indicates a promising potential for transferring pedological

  9. A Smartphone Application Significantly Improved Diabetes Self-Care Activities with High User Satisfaction

    Directory of Open Access Journals (Sweden)

    Yu Jin Kim

    2015-06-01

    Full Text Available BackgroundWe developed for the first time a smartphone application designed for diabetes self-management in Korea and registered a patent for the relevant algorithm. We also investigated the user satisfaction with the application and the change in diabetes related self-care activities after using the application.MethodsWe conducted a questionnaire survey on volunteers with diabetes who were using the application. Ninety subjects responded to the questionnaire between June 2012 and March 2013. A modified version of the Summary of Diabetes Self-Care Activities (SDSCA was used in this study.ResultsThe survey results exhibited a mean subject age of 44.0 years old, and males accounted for 78.9% of the subjects. Fifty percent of the subjects had diabetes for less than 3 years. The majority of respondents experienced positive changes in their clinical course after using the application (83.1% and were satisfied with the structure and completeness of the application (86.7%. Additionally, the respondents' answers indicated that the application was easy to use (96.7% and recommendable to others (97.7% and that they would continue using the application to manage their diabetes (96.7%. After using the Diabetes Notepad application, diabetes related self-care activities assessed by SDSCA displayed statistically significant improvements (P<0.05, except for the number of days of drinking.ConclusionThis smartphone-based application can be a useful tool leading to positive changes in diabetes related self-care activities and increase user satisfaction.

  10. Optimized Switch Allocation to Improve the Restoration Energy in Distribution Systems

    Science.gov (United States)

    Dezaki, Hamed H.; Abyaneh, Hossein A.; Agheli, Ali; Mazlumi, Kazem

    2012-01-01

    In distribution networks switching devices play critical role in energy restoration and improving reliability indices. This paper presents a novel objective function to optimally allocate switches in electric power distribution systems. Identifying the optimized location of the switches is a nonlinear programming problem (NLP). In the proposed objective function a new auxiliary function is used to simplify the calculation of the objective function. The output of the auxiliary function is binary. The genetic algorithm (GA) optimization method is used to solve this optimization problem. The proposed method is applied to a real distribution network and the results reveal that the method is successful.

  11. Improved VMAT planning for head and neck tumors with an advanced optimization algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Klippel, Norbert; Schmuecking, Michael; Terribilini, Dario; Geretschlaeger, Andreas; Aebersold, Daniel M.; Manser, Peter [Bern University Hospital - Inselspital (Switzerland). Div. of Medical Radiation Physics and Dept. of Radiation Oncology

    2015-07-01

    In this study, the ''Progressive Resolution Optimizer PRO3'' (Varian Medical Systems) is compared to the previous version PRO2'' with respect to its potential to improve dose sparing to the organs at risk (OAR) and dose coverage of the PTV for head and neck cancer patients. Materials and Methods For eight head and neck cancer patients, volumetric modulated arc therapy (VMAT) treatment plans were generated in this study. All cases have 2-3 phases and the total prescribed dose (PD) was 60-72 Gy in the PTV. The study is mainly focused on the phase 1 plans, which all have an identical PD of 54 Gy, and complex PTV structures with an overlap to the parotids. Optimization was performed based on planning objectives for the PTV according to ICRU83, and with minimal dose to spinal cord, and parotids outside PTV. In order to assess the quality of the optimization algorithms, an identical set of constraints was used for both, PRO2 and PRO3. The resulting treatment plans were investigated with respect to dose distribution based on the analysis of the dose volume histograms. Results For the phase 1 plans (PD = 54 Gy) the near maximum dose D{sub 2%} of the spinal cord, could be minimized to 22±5 Gy with PRO3, as compared to 32±12 Gy with PRO2, averaged for all patients. The mean dose to the parotids was also lower in PRO3 plans compared to PRO2, but the differences were less pronounced. A PTV coverage of V{sub 95%} = 97±1% could be reached with PRO3, as compared to 86±5% with PRO2. In clinical routine, these PRO2 plans would require modifications to obtain better PTV coverage at the cost of higher OAR doses. Conclusion A comparison between PRO3 and PRO2 optimization algorithms was performed for eight head and neck cancer patients. In general, the quality of VMAT plans for head and neck patients are improved with PRO3 as compared to PRO2. The dose to OARs can be reduced significantly, especially for the spinal cord. These reductions are achieved

  12. A Hybrid Improved Genetic Algorithm and Its Application in Dynamic Optimization Problems of Chemical Processes

    Institute of Scientific and Technical Information of China (English)

    SUN Fan; DU Wenli; QI Rongbin; QIAN Feng; ZHONG Weimin

    2013-01-01

    The solutions of dynamic optimization problems are usually very difficult due to their highly nonlinear and multidimensional nature.Genetic algorithm(GA)has been proved to be a feasible method when the gradient is difficult to calculate.Its advantage is that the control profiles at all time stages are optimized simultaneously,but its convergence is very slow in the later period of evolution and it is easily trapped in the local optimum.In this study,a hybrid improved genetic algorithm(HIGA)for solving dynamic optimization problems is proposed to overcome these defects.Simplex method(SM)is used to perform the local search in the neighborhood of the optimal solution.By using SM,the ideal searching direction of global optimal solution could be found as soon as possible and the convergence speed of the algorithm is improved.The hybrid algorithm presents some improvements,such as protecting the best individual,accepting immigrations,as well as employing adaptive crossover and Gaussian mutation operators.The efficiency of the proposed algorithm is demonstrated by solving several dynamic optimization problems.At last,HIGA is applied to the optimal production of secreted protein in a fed batch reactor and the optimal feed-rate found by HIGA is effective and relatively stable.

  13. Application of improved PSO to power transmission congestion management optimization model

    Institute of Scientific and Technical Information of China (English)

    李翔; 刘预胜; 杨淑霞

    2008-01-01

    The parameters of particles were encoded firstly, then the constraint conditions and fitness degree were processed, and the calculation steps of the improved PSO algorithm were presented. Finally, the issues with the adoption of the improved PSO algorithm were solved and the results were analyzed. The results show that it is beneficial to obtaining the optimal solution by increasing the number of particles but that will also increase the operation time. On the aspects of solving continuous differentiable non-linear optimization model with equality and inequality constraints, the optimization result of PSO algorithm is the same as that of the interior point method. Compared with genetic algorithms (GA), PSO algorithm is more effective in the local optimization, and unlike GA, it will not be early maturity. Meanwhile, PSO algorithm is also more effective in the boundary optimization than genetic algorithm.

  14. An improved model for the oPtImal Measurement Probes Allocation tool

    Energy Technology Data Exchange (ETDEWEB)

    Sterle, C., E-mail: claudio.sterle@unina.it [Consorzio CREATE/Dipartimento di Ingegneria Elettrica e delle Tecnologie dell’Informazione, Università degli Studi di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); Neto, A.C. [Fusion for Energy, 08019 Barcelona (Spain); De Tommasi, G. [Consorzio CREATE/Dipartimento di Ingegneria Elettrica e delle Tecnologie dell’Informazione, Università degli Studi di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy)

    2015-10-15

    Highlights: • The problem of optimally allocating the probes of a diagnostic system is tackled. • The problem is decomposed in two consecutive optimization problems. • Two original ILP models are proposed and sequentially solved to optimality. • The proposed ILP models improve and extend the previous work present in literature. • Real size instances have been optimally solved with very low computation time. - Abstract: The oPtImal Measurement Probes Allocation (PIMPA) tool has been recently proposed in [1] to maximize the reliability of a tokamak diagnostic system against the failure of one or more of the processing nodes. PIMPA is based on the solution of integer linear programming (ILP) problems, and it minimizes the effect of the failure of a data acquisition component. The first formulation of the PIMPA model did not support the concept of individual slots. This work presents an improved ILP model that addresses the above mentioned problem, by taking into account all the individual probes.

  15. Optimally oriented grooves on dental implants improve bone quality around implants under repetitive mechanical loading.

    Science.gov (United States)

    Kuroshima, Shinichiro; Nakano, Takayoshi; Ishimoto, Takuya; Sasaki, Muneteru; Inoue, Maaya; Yasutake, Munenori; Sawase, Takashi

    2017-01-15

    The aim was to investigate the effect of groove designs on bone quality under controlled-repetitive load conditions for optimizing dental implant design. Anodized Ti-6Al-4V alloy implants with -60° and +60° grooves around the neck were placed in the proximal tibial metaphysis of rabbits. The application of a repetitive mechanical load was initiated via the implants (50N, 3Hz, 1800 cycles, 2days/week) at 12weeks after surgery for 8weeks. Bone quality, defined as osteocyte density and degree of biological apatite (BAp) c-axis/collagen fibers, was then evaluated. Groove designs did not affect bone quality without mechanical loading; however, repetitive mechanical loading significantly increased bone-to-implant contact, bone mass, and bone mineral density (BMD). In +60° grooves, the BAp c-axis/collagen fibers preferentially aligned along the groove direction with mechanical loading. Moreover, osteocyte density was significantly higher both inside and in the adjacent region of the +60° grooves, but not -60° grooves. These results suggest that the +60° grooves successfully transmitted the load to the bone tissues surrounding implants through the grooves. An optimally oriented groove structure on the implant surface was shown to be a promising way for achieving bone tissue with appropriate bone quality. This is the first report to propose the optimal design of grooves on the necks of dental implants for improving bone quality parameters as well as BMD. The findings suggest that not only BMD, but also bone quality, could be a useful clinical parameter in implant dentistry.

  16. Study on optimal design to improve auto-body structural crashworthiness

    Institute of Scientific and Technical Information of China (English)

    WANG Hai-liang; LIN Zhong-qin

    2005-01-01

    In this paper the optimal model of the main energy absorbed structure in an auto-body "front rail",based on structural crashworthiness is built. For an optimal design on structure crashworthiness, the new method is based on a response surface model and Pareto GA, which improves the efficiency and flexibility of an optimal design, that is brought forward. The traditional optimal method can not be applied in the design of an impact structure due to the high nonlinearity and large time cost of crashworthiness FE analysis. So the method of an optimal design based on crashworthiness is brought forward. After constructing the response surface model of auto-body crashworthiness, the Pareto GA can be applied to find the multi-objective globally. The optimal solution set can then be used to provide many scheme combinations for choice structural parameters.To acquire the optimized structure parameters on front rail crashworthiness, this simplified model of an original design is built. After studying various ways of reinforcing the cross-section to control the structural failure mode, a better method has been found. On the precondition of not increasing the mass of the structure, an optimal design of the front rail is performed further. Finally, the optimized scheme is implemented in the full-car impact analysis and crashworthiness is studied. With proper measures to control deformation of the front rail structure the crashworthiness can be improved with minor structural modifications.

  17. Waste Minimization Improvements Achieved Through Six Sigma Analysis Result In Significant Cost Savings

    Energy Technology Data Exchange (ETDEWEB)

    Mousseau, Jeffrey, D.; Jansen, John, R.; Janke, David, H.; Plowman, Catherine, M.

    2003-02-26

    Improved waste minimization practices at the Department of Energy's (DOE) Idaho National Engineering and Environmental Laboratory (INEEL) are leading to a 15% reduction in the generation of hazardous and radioactive waste. Bechtel, BWXT Idaho, LLC (BBWI), the prime management and operations contractor at the INEEL, applied the Six Sigma improvement process to the INEEL Waste Minimization Program to review existing processes and define opportunities for improvement. Our Six Sigma analysis team: composed of an executive champion, process owner, a black belt and yellow belt, and technical and business team members used this statistical based process approach to analyze work processes and produced ten recommendations for improvement. Recommendations ranged from waste generator financial accountability for newly generated waste to enhanced employee recognition programs for waste minimization efforts. These improvements have now been implemented to reduce waste generation rates and are producing positive results.

  18. An optimized procedure greatly improves EST vector contamination removal

    Directory of Open Access Journals (Sweden)

    Wu Huan-Bin

    2007-11-01

    Full Text Available Abstract Background The enormous amount of sequence data available in the public domain database has been a gold mine for researchers exploring various themes in life sciences, and hence the quality of such data is of serious concern to researchers. Removal of vector contamination is one of the most significant operations to obtain accurate sequence data containing only a cDNA insert from the basecalls output by an automatic DNA sequencer. Popular bioinformatics programs to accomplish vector trimming include LUCY, cross_match and SeqClean. Results In a recent study, where the program SeqClean was used to remove vector contamination from our test set of EST data compiled through various library construction systems, however, a significant number of errors remained after preliminary trimming. These errors were later almost completely corrected by simply using a re-linearized form of the cloning vector to compare against the target ESTs. The modified trimming procedure for SeqClean was also compared with the trimming efficiency of the other two popular programs, LUCY2, and cross_match. Using SeqClean with a re-linearized form of the cloning vector significantly surpassed the other two programs in all tested conditions, while the performance of the other two programs was not influenced by the modified procedure. Vector contamination in dbEST was also investigated in this study: 2203 out of the 48212 ESTs sampled from dbEST (2007-04-18 freeze were found to match sequences in UNIVEC. Conclusion Vector contamination remains a serious concern to the data quality in the public sequence database nowadays. Based on the results presented here, we feel that our modified procedure with SeqClean should be recommended to all researchers for the task of vector removal from EST or genomic sequences.

  19. A BP Neural Network Based on Improved Particle Swarm Optimization and its Application in Reliability Forecasting

    Directory of Open Access Journals (Sweden)

    Heqing Li

    2013-07-01

    Full Text Available The basic Particle Swarm Optimization (PSO algorithm and its principle have been introduced, the Particle Swarm Optimization has low accelerate speed and can be easy to fall into local extreme value, so the Particle Swarm Optimization based on the improved inertia weight is presented. This method means using nonlinear decreasing weight factor to change the fundamental ways of PSO. To allow full play to the approximation capability of the function of BP neural network and overcome the main shortcomings of its liability to fall into local extreme value and the study proposed a concept of applying improved PSO algorithm and BP network jointly to optimize the original weight and threshold value of network and incorporating the improved PSO algorithm into BP network to establish a improved PSO-BP network system. This method improves convergence speed and the ability to search optimal value. We apply the improved particle swarm algorithm to reliability prediction. Compared with the traditional BP method, this kind of algorithm can minimize errors and improve convergence speed at the same time.

  20. Probability-Based Software for Grid Optimization: Improved Power System Operations Using Advanced Stochastic Optimization

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-02-24

    GENI Project: Sandia National Laboratories is working with several commercial and university partners to develop software for market management systems (MMSs) that enable greater use of renewable energy sources throughout the grid. MMSs are used to securely and optimally determine which energy resources should be used to service energy demand across the country. Contributions of electricity to the grid from renewable energy sources such as wind and solar are intermittent, introducing complications for MMSs, which have trouble accommodating the multiple sources of price and supply uncertainties associated with bringing these new types of energy into the grid. Sandia’s software will bring a new, probability-based formulation to account for these uncertainties. By factoring in various probability scenarios for electricity production from renewable energy sources in real time, Sandia’s formula can reduce the risk of inefficient electricity transmission, save ratepayers money, conserve power, and support the future use of renewable energy.

  1. Improved Genetic Algorithm Optimization for Forward Vehicle Detection Problems

    Directory of Open Access Journals (Sweden)

    Longhui Gang

    2015-07-01

    Full Text Available Automated forward vehicle detection is an integral component of many advanced driver-assistance systems. The method based on multi-visual information fusion, with its exclusive advantages, has become one of the important topics in this research field. During the whole detection process, there are two key points that should to be resolved. One is to find the robust features for identification and the other is to apply an efficient algorithm for training the model designed with multi-information. This paper presents an adaptive SVM (Support Vector Machine model to detect vehicle with range estimation using an on-board camera. Due to the extrinsic factors such as shadows and illumination, we pay more attention to enhancing the system with several robust features extracted from a real driving environment. Then, with the introduction of an improved genetic algorithm, the features are fused efficiently by the proposed SVM model. In order to apply the model in the forward collision warning system, longitudinal distance information is provided simultaneously. The proposed method is successfully implemented on a test car and evaluation experimental results show reliability in terms of both the detection rate and potential effectiveness in a real-driving environment.

  2. An Improved Brain Storm Optimization with Differential Evolution Strategy for Applications of ANNs

    Directory of Open Access Journals (Sweden)

    Zijian Cao

    2015-01-01

    Full Text Available Brain Storm Optimization (BSO algorithm is a swarm intelligence algorithm inspired by human being’s behavior of brainstorming. The performance of BSO is maintained by the creating process of ideas, but when it cannot find a better solution for some successive iterations, the result will be so inefficient that the population might be trapped into local optima. In this paper, we propose an improved BSO algorithm with differential evolution strategy and new step size method. Firstly, differential evolution strategy is incorporated into the creating operator of ideas to allow BSO jump out of stagnation, owing to its strong searching ability. Secondly, we introduce a new step size control method that can better balance exploration and exploitation at different searching generations. Finally, the proposed algorithm is first tested on 14 benchmark functions of CEC 2005 and then is applied to train artificial neural networks. Comparative experimental results illustrate that the proposed algorithm performs significantly better than the original BSO.

  3. Conditioning of sewage sludge with electrolysis: effectiveness and optimizing study to improve dewaterability.

    Science.gov (United States)

    Yuan, Haiping; Zhu, Nanwen; Song, Lijie

    2010-06-01

    The potential benefits of electrolysis-conditioned sludge dewatering treatment were investigated in this paper. Focuses were placed on effectiveness and factors affecting such novel application of electrolysis process. Experiments have demonstrated that a significant improvement of sludge dewaterability evaluated by capillary suction time (CST) could be obtained at a relative low value of electrolysis voltage. A Box-Behnken experimental design based on the response surface methodology (RSM) was applied to evaluate the optimum of the influencing variables. The optimal values for electrolysis voltage, electrode distance and electrolysis time are 21 V, 5 cm and 12 min, respectively, at which the CST reduction efficiency of 18.8+/-3.1% could be achieved, this agreed with that predicted by an established polynomial model in this study.

  4. Cross-functional clinical teams: significant improvement in operating room quality and productivity.

    Science.gov (United States)

    Davis, R N

    1993-01-01

    This paper will describe a successful application of Quality Improvement concepts to the complex Perioperative System at an academic medical center in the Northeast. The initiation of multi-disciplinary teams (including surgeons, anesthesiologists, and nurse managers) will be discussed, as will the steps, skills, and techniques employed. The paper will catalogue keys to success from those observed during this and five similar recent Quality Improvement engagements facilitated by such a process.

  5. An energy-based perturbation and a taboo strategy for improving the searching ability of stochastic structural optimization methods

    Science.gov (United States)

    Cheng, Longjiu; Cai, Wensheng; Shao, Xueguang

    2005-03-01

    An energy-based perturbation and a new idea of taboo strategy are proposed for structural optimization and applied in a benchmark problem, i.e., the optimization of Lennard-Jones (LJ) clusters. It is proved that the energy-based perturbation is much better than the traditional random perturbation both in convergence speed and searching ability when it is combined with a simple greedy method. By tabooing the most wide-spread funnel instead of the visited solutions, the hit rate of other funnels can be significantly improved. Global minima of (LJ) clusters up to 200 atoms are found with high efficiency.

  6. Improvement in Energy Optimization in Telecommunication Network Service

    Directory of Open Access Journals (Sweden)

    Kadiri Kamoru. O

    2014-09-01

    Full Text Available Energy-efficient operation is an important issue today in telecommunication networks and in the near future. Due to the fact that the energy consumption rises with the increased in demand for capacity and network speed, this arises a strategies for a sustainable network management. It is a well-known fact that traffic demands vary significantly over periods and areas, most notably in day/night- and in weekly cycles. This provides the main potential for energy-saving strategies. Here is the question of how much power is necessary to operate a network during peak or low-traffic times? How much energy is spent in the core and in metro regions of the network and how big are the savings in low-demand scenarios if we always assume the system power-minimum in these situations? The study respects realistic side constraints, such as protection requirements and routing schemes, and takes the special structure of an extensive nation-wide optical network, including backbone and regional sections, into account. This paper presents a comprehensive summary of recent work addressing energy efficient and low-power design within all layers of the telecommunication network

  7. Optimization of factors to obtain cassava starch films with improved mechanical properties

    Science.gov (United States)

    Monteiro, Mayra; Oliveira, Victor; Santos, Francisco; Barros Neto, Eduardo; Silva, Karyn; Silva, Rayane; Henrique, João; Chibério, Abimaelle

    2017-08-01

    In this study, was investigated the optimization of the factors that significantly influenced the mechanical property improvement of cassava starch films through complete factorial design 23. The factors to be analyzed were cassava starch, glycerol and modified clay contents. A regression model was proposed by the factorial analysis, aiming to estimate the condition of the individual factors investigated in the optimum state of the mechanical properties of the biofilm, using the following statistical tool: desirability function and response surface. The response variable that delimits the improvement of the mechanical property of the biofilm is the tensile strength, such improvement is obtained by maximizing the response variable. The factorial analysis showed that the best combination of factor configurations to reach the best response was found to be: with 5g of cassava starch, 10% of glycerol and 5% of modified clay, both percentages in relation to the dry mass of starch used. In addition, the starch biofilm showing the lowest response contained 2g of cassava starch, 0% of modified clay and 30% of glycerol, and was consequently considered the worst biofilm.

  8. Improving transition between power optimization and power limitation of variable speed/variable pitch wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.D.; Bindner, H. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark); Rebsdorf, A. [Vestas Wind Systems A/S, Lem (Denmark)

    1999-03-01

    The paper summarises and describes the main results of a recently performed study of improving the transition between power optimization and power limitation for variable speed/variable pitch wind turbines. The results show that the capability of varying the generator speed also can be exploited in the transition stage to improve the quality of the generated power. (au)

  9. Short term hydrothermal scheduling via improved honey-bee mating optimization algorithm

    Directory of Open Access Journals (Sweden)

    hamed baradaran tavakoli

    2012-11-01

    Full Text Available In this paper, a new approach for solving short term hydrothermal scheduling problem is suggested, to minimize the total production cost and to produce electrical energy in an optimized way, by using honey-bee mating optimization algorithm. In the proposed method, lots of the hydrothermal system constraints such as power balance, water balance, time delay between reservoirs, volume limits and the operation limits of hydro and thermal plants, are considered. Therefore, the problem of short term hydrothermal scheduling becomes a complicated and nonlinear problem. In this paper, in addition to implementing the honey-bee mating optimization on a sample system, the improved honey-bee mating optimization algorithm has also been tested and analyzed. With regard to the simulation results, it is apparent that the improved honey-bee mating optimization has far higher convergence speed and takes less time, and less total cost in comparison with honey-bee mating optimization algorithm, genetic algorithm, particle swarm optimization algorithm and other optimization methods.

  10. Improving the quality of sleep with an optimal pillow: a randomized, comparative study.

    Science.gov (United States)

    Jeon, Mi Yang; Jeong, HyeonCheol; Lee, SeungWon; Choi, Wonjae; Park, Jun Hyuck; Tak, Sa Jin; Choi, Dae Ho; Yim, Jongeun

    2014-07-01

    Because sleep comprises one-third of a person's life, using an optimal pillow for appropriate neck support to maintain cervical curve may contribute to improve quality of sleep. Design of orthopedic pillow conforms to orthopedic guidelines to ensure the right support of the cervical curve. The aim of this study was to investigate effect of different pillow shape and content on cervical curve, pillow temperature, and pillow comfort. A feather pillow is regarded as a standard pillow, and a memory foam pillow is one of the most popular pillows among pillow users. We, therefore, compared these two pillows with an orthopedic pillow. Twenty healthy subjects (10 men and 10 women; age range, 21-30 years) participated in the study. Each subject was asked to assume the supine position with 3 different pillows for 30 minute in each trial and then cervical curve, pillow temperature, and pillow comfort were measured. When comparing the cervical curve of the 3 different pillows, that of the orthopedic pillow was significantly higher than that of the other 2 pillows (p optimal pillow for sleep quality.

  11. Experimental verification of optically optimized CuGaSe2 top cell for improving chalcopyrite tandems

    Science.gov (United States)

    Schmid, M.; Caballero, R.; Klenk, R.; Krč, J.; Rissom, T.; Topi, M.; Lux-Steiner, M. Ch.

    2010-07-01

    An efficient tandem solar cell requires a top cell which is highly transparent below the energy gap of its absorber. Previously we had reported on a theoretically optimized CuGaSe2top cell stack based on realistic material properties. It promised a significant increase in optical transparency and, consequently, enhanced CuGaSe2/Cu(In,Ga)Se2tandem efficiency. Here we present the first steps taken towards the experimental realization of this optimized tandem. We started with a mechanically stacked device which achieved 8.5% efficiency. Optical measurements of the improved top cells and corresponding photo current densities of the filtered bottom cell are reported. The experimental findings are in agreement with the optical modeling. These data are used to assess the level of tandem performance that could be accomplished in the near future and to discuss the priorities of further research. This article has been previously published in PV Direct, the former name of EPJ Photovoltaics.

  12. Spot Welding Parameter Optimization to Improve Weld Characteristics for Dissimilar Metals

    Directory of Open Access Journals (Sweden)

    Aravinthan Arumugam

    2015-01-01

    Full Text Available Abstract Resistance spot welding is a process which is widely used in the automotive industry to join steel parts of various thicknesses and types. The current practice in the automotive industry in determining the welding schedule which will be used in the welding process is based on welding table or experiences. This however may not be the optimum welding schedule that will give the best spot weld quality. This work concentrates on the parameter optimization when spot welding steels with dissimilar thickness and type using Grey Based Taguchi Method. The experimentation in this work used a L9 orthogonal array with three factors with each factor having three levels. The three factors used are welding current weld time and electrode force. The three weld characteristics that were optimized are weld strength weld nugget diameter and weld indentation. The analysis of variance ANOVA that was carried out showed that welding current gave the most significant contribution in the optimum welding schedule. The comparison test that was carried out to compare the current welding schedule and the optimum welding schedule showed distinct improvement in the increase of weld diameter and weld strengthas well as decrease in electrode indentation.

  13. Integrated Medical Model (IMM) Optimization Version 4.0 Functional Improvements

    Science.gov (United States)

    Arellano, John; Young, M.; Boley, L.; Garcia, Y.; Saile, L.; Walton, M.; Kerstman, E.; Reyes, D.; Goodenow, D. A.; Myers, J. G.

    2016-01-01

    The IMMs ability to assess mission outcome risk levels relative to available resources provides a unique capability to provide guidance on optimal operational medical kit and vehicle resources. Post-processing optimization allows IMM to optimize essential resources to improve a specific model outcome such as maximization of the Crew Health Index (CHI), or minimization of the probability of evacuation (EVAC) or the loss of crew life (LOCL). Mass and or volume constrain the optimized resource set. The IMMs probabilistic simulation uses input data on one hundred medical conditions to simulate medical events that may occur in spaceflight, the resources required to treat those events, and the resulting impact to the mission based on specific crew and mission characteristics. Because IMM version 4.0 provides for partial treatment for medical events, IMM Optimization 4.0 scores resources at the individual resource unit increment level as opposed to the full condition-specific treatment set level, as done in version 3.0. This allows the inclusion of as many resources as possible in the event that an entire set of resources called out for treatment cannot satisfy the constraints. IMM Optimization version 4.0 adds capabilities that increase efficiency by creating multiple resource sets based on differing constraints and priorities, CHI, EVAC, or LOCL. It also provides sets of resources that improve mission-related IMM v4.0 outputs with improved performance compared to the prior optimization. The new optimization represents much improved fidelity that will improve the utility of the IMM 4.0 for decision support.

  14. Knee joint secondary motion accuracy improved by quaternion-based optimizer with bony landmark constraints.

    Science.gov (United States)

    Wang, Hongsheng; Zheng, Naiqaun Nigel

    2010-12-01

    Skin marker-based motion analysis has been widely used in biomechanical studies and clinical applications. Unfortunately, the accuracy of knee joint secondary motions is largely limited by the nonrigidity nature of human body segments. Numerous studies have investigated the characteristics of soft tissue movement. Utilizing these characteristics, we may improve the accuracy of knee joint motion measurement. An optimizer was developed by incorporating the soft tissue movement patterns at special bony landmarks into constraint functions. Bony landmark constraints were assigned to the skin markers at femur epicondyles, tibial plateau edges, and tibial tuberosity in a motion analysis algorithm by limiting their allowed position space relative to the underlying bone. The rotation matrix was represented by quaternion, and the constrained optimization problem was solved by Fletcher's version of the Levenberg-Marquardt optimization technique. The algorithm was validated by using motion data from both skin-based markers and bone-mounted markers attached to fresh cadavers. By comparing the results with the ground truth bone motion generated from the bone-mounted markers, the new algorithm had a significantly higher accuracy (root-mean-square (RMS) error: 0.7 ± 0.1 deg in axial rotation and 0.4 ± 0.1 deg in varus-valgus) in estimating the knee joint secondary rotations than algorithms without bony landmark constraints (RMS error: 1.7 ± 0.4 deg in axial rotation and 0.7 ± 0.1 deg in varus-valgus). Also, it predicts a more accurate medial-lateral translation (RMS error: 0.4 ± 0.1 mm) than the conventional techniques (RMS error: 1.2 ± 0.2 mm). The new algorithm, using bony landmark constrains, estimates more accurate secondary rotations and medial-lateral translation of the underlying bone.

  15. Vestibular Stochastic Resonance as a Method to Improve Balance Function: Optimization of Stimulus Characteristics

    Science.gov (United States)

    Mulavara, Ajitkumar; Fiedler, Matthew; Kofman, Igor; Peters, Brian; Wood, Scott; Serrador, Jorge; Cohen, Helen; Reschke, Millard; Bloomberg, Jacob

    2010-01-01

    Stochastic resonance (SR) is a mechanism by which noise can assist and enhance the response of neural systems to relevant sensory signals. Application of imperceptible SR noise coupled with sensory input through the proprioceptive, visual, or vestibular sensory systems has been shown to improve motor function. Specifically, studies have shown that that vestibular electrical stimulation by imperceptible stochastic noise, when applied to normal young and elderly subjects, significantly improved their ocular stabilization reflexes in response to whole-body tilt as well as balance performance during postural disturbances. The goal of this study was to optimize the characteristics of the stochastic vestibular signals for balance performance during standing on an unstable surface. Subjects performed a standardized balance task of standing on a block of 10 cm thick medium density foam with their eyes closed for a total of 40 seconds. Stochastic electrical stimulation was applied to the vestibular system through electrodes placed over the mastoid process behind the ears during the last 20 seconds of the test period. A custom built constant current stimulator with subject isolation delivered the stimulus. Stimulation signals were generated with frequencies in the bandwidth of 1-2 Hz and 0.01-30 Hz. Amplitude of the signals were varied in the range of 0- +/-700 micro amperes with the RMS of the signal increased by 30 micro amperes for each 100 micro amperes increase in the current range. Balance performance was measured using a force plate under the foam block and inertial motion sensors placed on the torso and head segments. Preliminary results indicate that balance performance is improved in the range of 10-25% compared to no stimulation conditions. Subjects improved their performance consistently across the blocks of stimulation. Further the signal amplitude at which the performance was maximized was different in the two frequency ranges. Optimization of the frequency and

  16. Improved quantum-behaved particle swarm optimization with local search strategy

    Directory of Open Access Journals (Sweden)

    Maolong Xi

    2017-03-01

    Full Text Available Quantum-behaved particle swarm optimization, which was motivated by analysis of particle swarm optimization and quantum system, has shown compared performance in finding the optimal solutions for many optimization problems to other evolutionary algorithms. To address the problem of premature, a local search strategy is proposed to improve the performance of quantum-behaved particle swarm optimization. In proposed local search strategy, a super particle is presented which is a collection body of randomly selected particles’ dimension information in the swarm. The selected probability of particles in swarm is different and determined by their fitness values. To minimization problems, the fitness value of one particle is smaller; the selected probability is more and will contribute more information in constructing the super particle. In addition, in order to investigate the influence on algorithm performance with different local search space, four methods of computing the local search radius are applied in local search strategy and propose four variants of local search quantum-behaved particle swarm optimization. Empirical studies on a suite of well-known benchmark functions are undertaken in order to make an overall performance comparison among the proposed methods and other quantum-behaved particle swarm optimization. The simulation results show that the proposed quantum-behaved particle swarm optimization variants have better advantages over the original quantum-behaved particle swarm optimization.

  17. A Novel Optimization Technique to Improve Gas Recognition by Electronic Noses Based on the Enhanced Krill Herd Algorithm.

    Science.gov (United States)

    Wang, Li; Jia, Pengfei; Huang, Tailai; Duan, Shukai; Yan, Jia; Wang, Lidan

    2016-08-12

    An electronic nose (E-nose) is an intelligent system that we will use in this paper to distinguish three indoor pollutant gases (benzene (C₆H₆), toluene (C₇H₈), formaldehyde (CH₂O)) and carbon monoxide (CO). The algorithm is a key part of an E-nose system mainly composed of data processing and pattern recognition. In this paper, we employ support vector machine (SVM) to distinguish indoor pollutant gases and two of its parameters need to be optimized, so in order to improve the performance of SVM, in other words, to get a higher gas recognition rate, an effective enhanced krill herd algorithm (EKH) based on a novel decision weighting factor computing method is proposed to optimize the two SVM parameters. Krill herd (KH) is an effective method in practice, however, on occasion, it cannot avoid the influence of some local best solutions so it cannot always find the global optimization value. In addition its search ability relies fully on randomness, so it cannot always converge rapidly. To address these issues we propose an enhanced KH (EKH) to improve the global searching and convergence speed performance of KH. To obtain a more accurate model of the krill behavior, an updated crossover operator is added to the approach. We can guarantee the krill group are diversiform at the early stage of iterations, and have a good performance in local searching ability at the later stage of iterations. The recognition results of EKH are compared with those of other optimization algorithms (including KH, chaotic KH (CKH), quantum-behaved particle swarm optimization (QPSO), particle swarm optimization (PSO) and genetic algorithm (GA)), and we can find that EKH is better than the other considered methods. The research results verify that EKH not only significantly improves the performance of our E-nose system, but also provides a good beginning and theoretical basis for further study about other improved krill algorithms' applications in all E-nose application areas.

  18. Bionic optimization in structural design stochastically based methods to improve the performance of parts and assemblies

    CERN Document Server

    Gekeler, Simon

    2016-01-01

    The book provides suggestions on how to start using bionic optimization methods, including pseudo-code examples of each of the important approaches and outlines of how to improve them. The most efficient methods for accelerating the studies are discussed. These include the selection of size and generations of a study’s parameters, modification of these driving parameters, switching to gradient methods when approaching local maxima, and the use of parallel working hardware. Bionic Optimization means finding the best solution to a problem using methods found in nature. As Evolutionary Strategies and Particle Swarm Optimization seem to be the most important methods for structural optimization, we primarily focus on them. Other methods such as neural nets or ant colonies are more suited to control or process studies, so their basic ideas are outlined in order to motivate readers to start using them. A set of sample applications shows how Bionic Optimization works in practice. From academic studies on simple fra...

  19. Parameter estimation for chaotic systems based on improved boundary chicken swarm optimization

    Science.gov (United States)

    Chen, Shaolong; Yan, Renhuan

    2016-10-01

    Estimating unknown parameters for chaotic system is a key problem in the field of chaos control and synchronization. Through constructing an appropriate fitness function, parameter estimation of chaotic system could be converted to a multidimensional parameter optimization problem. In this paper, a new method base on improved boundary chicken swarm optimization (IBCSO) algorithm is proposed for solving the problem of parameter estimation in chaotic system. However, to the best of our knowledge, there is no published research work on chicken swarm optimization for parameters estimation of chaotic system. Computer simulation based on Lorenz system and comparisons with chicken swarm optimization, particle swarm optimization, and genetic algorithm shows the effectiveness and feasibility of the proposed method.

  20. Reducing dysfunctional beliefs about sleep does not significantly improve insomnia in cognitive behavioral therapy.

    Science.gov (United States)

    Okajima, Isa; Nakajima, Shun; Ochi, Moeko; Inoue, Yuichi

    2014-01-01

    The present study examined to examine whether improvement of insomnia is mediated by a reduction in sleep-related dysfunctional beliefs through cognitive behavioral therapy for insomnia. In total, 64 patients with chronic insomnia received cognitive behavioral therapy for insomnia consisting of 6 biweekly individual treatment sessions of 50 minutes in length. Participants were asked to complete the Athens Insomnia Scale and the Dysfunctional Beliefs and Attitudes about Sleep scale both at the baseline and at the end of treatment. The results showed that although cognitive behavioral therapy for insomnia greatly reduced individuals' scores on both scales, the decrease in dysfunctional beliefs and attitudes about sleep with treatment did not seem to mediate improvement in insomnia. The findings suggest that sleep-related dysfunctional beliefs endorsed by patients with chronic insomnia may be attenuated by cognitive behavioral therapy for insomnia, but changes in such beliefs are not likely to play a crucial role in reducing the severity of insomnia.

  1. Optimization of Printed Antennas Using Genetic Algorithm Coupled with Improved Cavity Model

    Science.gov (United States)

    Sathi, Vahid; Ehteshami, Nasrin; Ghobadi, C.

    2012-06-01

    An accurate electromagnetic optimization tool for designing rectangular and circular microstrip antennas is proposed. This optimization method is based on the improved cavity model analysis in conjunction with the well-known genetic algorithm, which is employed to optimize the dimensions and feed point location of rectangular and circular microstrip antennas. Results obtained by this technique agree quite well with the measured data and the data obtained by the FEM based software HFSS by ANSOFT. This technique can be fruitfully used in microwave CAD applications.

  2. Optimal Location of Static Var Compensator Using Bat Algorithm for the Improvement of Voltage Profile

    Directory of Open Access Journals (Sweden)

    D. Venugopal

    2015-04-01

    Full Text Available This paper proposes optimal location of FACTS devices in power system using Evolutionary algorithms. The location of FACTS controllers, their type and rated values are optimized simultaneously by using the proposed algorithm. From the FACTS devices family, shunt device Static Var Compensator (SVC is considered. The proposed BAT algorithm is a very effective method for the optimal choice and placement of SVC device to improve the Voltage profile of power systems. The proposed algorithm has been applied to IEEE 30 bus system.

  3. Exploiting Additive Manufacturing Infill in Topology Optimization for Improved Buckling Load

    Directory of Open Access Journals (Sweden)

    Anders Clausen

    2016-06-01

    Full Text Available Additive manufacturing (AM permits the fabrication of functionally optimized components with high geometrical complexity. The opportunity of using porous infill as an integrated part of the manufacturing process is an example of a unique AM feature. Automated design methods are still incapable of fully exploiting this design freedom. In this work, we show how the so-called coating approach to topology optimization provides a means for designing infill-based components that possess a strongly improved buckling load and, as a result, improved structural stability. The suggested approach thereby addresses an important inadequacy of the standard minimum compliance topology optimization approach, in which buckling is rarely accounted for; rather, a satisfactory buckling load is usually assured through a post-processing step that may lead to sub-optimal components. The present work compares the standard and coating approaches to topology optimization for the MBB beam benchmark case. The optimized structures are additively manufactured using a filamentary technique. This experimental study validates the numerical model used in the coating approach. Depending on the properties of the infill material, the buckling load may be more than four times higher than that of solid structures optimized under the same conditions.

  4. Optimization of Damper Top Mount Characteristics to Improve Vehicle Ride Comfort and Harshness

    Directory of Open Access Journals (Sweden)

    Mina M. S. Kaldas

    2014-01-01

    Full Text Available A novel optimization technique for optimizing the damper top mount characteristics to improve vehicle ride comfort and harshness is developed. The proposed optimization technique employs a new combined objective function based on ride comfort, harshness, and impact harshness evaluation. A detailed and accurate damper top mount mathematical model is implemented inside a validated quarter vehicle model to provide a realistic simulation environment for the optimization study. The ride comfort and harshness of the quarter vehicle are evaluated by analyzing the body acceleration in different frequency ranges. In addition, the top mount deformation is considered as a penalty factor for the system performance. The influence of the ride comfort and harshness weighting parameters of the proposed objective function on the optimal damper top mount characteristics is studied. The dynamic stiffness of the damper top mount is used to describe the optimum damper top mount characteristics for different optimization case studies. The proposed optimization routine is able to find the optimum characteristics of the damper top mount which improve the ride comfort and the harshness performances together.

  5. Improved Genetic Algorithm with Two-Level Approximation for Truss Optimization by Using Discrete Shape Variables

    Directory of Open Access Journals (Sweden)

    Shen-yan Chen

    2015-01-01

    Full Text Available This paper presents an Improved Genetic Algorithm with Two-Level Approximation (IGATA to minimize truss weight by simultaneously optimizing size, shape, and topology variables. On the basis of a previously presented truss sizing/topology optimization method based on two-level approximation and genetic algorithm (GA, a new method for adding shape variables is presented, in which the nodal positions are corresponding to a set of coordinate lists. A uniform optimization model including size/shape/topology variables is established. First, a first-level approximate problem is constructed to transform the original implicit problem to an explicit problem. To solve this explicit problem which involves size/shape/topology variables, GA is used to optimize individuals which include discrete topology variables and shape variables. When calculating the fitness value of each member in the current generation, a second-level approximation method is used to optimize the continuous size variables. With the introduction of shape variables, the original optimization algorithm was improved in individual coding strategy as well as GA execution techniques. Meanwhile, the update strategy of the first-level approximation problem was also improved. The results of numerical examples show that the proposed method is effective in dealing with the three kinds of design variables simultaneously, and the required computational cost for structural analysis is quite small.

  6. Research on Demand Prediction of Fresh Food Supply Chain Based on Improved Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    He Wang

    2015-04-01

    Full Text Available Demand prediction of supply chain is an important content and the first premise in supply management of different enterprises and has become one of the difficulties and hot research fields for the researchers related. The paper takes fresh food demand prediction for example and presents a new algorithm for predicting demand of fresh food supply chain. First, the working principle and the root causes of the defects of particle swarm optimization algorithm are analyzed in the study; Second, the study designs a new cloud particle swarm optimization algorithm to guarantee the effectiveness of particles in later searching phase and redesigns its cloud global optimization searching method and crossover operation; Finally, a certain fresh food supply chain is taken for example to illustrate the validity and feasibility of the improved algorithm and the experimental results show that the improved algorithm can improve prediction accuracy and calculation efficiency when used for demand prediction of fresh food supply chain.

  7. Method of improving photoelectric efficiency for laser power beaming based on photovoltaic cell layout optimization

    Science.gov (United States)

    Li, Beibei; Li, Xiaojiang

    2017-02-01

    In accordance with the high impact of the uneven distribution of laser beam power on the photovoltaic efficiency of photovoltaic cell (PV) array, a method based on PV layout optimization is proposed to improve the photovoltaic efficiency. First of all, a mathematical model of series-parallel PV array is built, and by analyzing the influencing factors on photovoltaic efficiency, the idea and scheme to improve the photovoltaic efficiency based on PV layout optimization is provided; then, the MATLAB/Simulink simulation tool is used to simulate the effects of improving photoelectric efficiency. The simulation results show that compared to the traditional PV array, the optimized PV array can obtain higher photovoltaic efficiency, and compared to the situation with uneven temperature distribution, the array efficiency has higher efficiency under even temperature distribution.

  8. Simultaneous Camera Path Optimization and Distraction Removal for Improving Amateur Video.

    Science.gov (United States)

    Zhang, Fang-Lue; Wang, Jue; Zhao, Han; Martin, Ralph R; Hu, Shi-Min

    2015-12-01

    A major difference between amateur and professional video lies in the quality of camera paths. Previous work on video stabilization has considered how to improve amateur video by smoothing the camera path. In this paper, we show that additional changes to the camera path can further improve video aesthetics. Our new optimization method achieves multiple simultaneous goals: 1) stabilizing video content over short time scales; 2) ensuring simple and consistent camera paths over longer time scales; and 3) improving scene composition by automatically removing distractions, a common occurrence in amateur video. Our approach uses an L(1) camera path optimization framework, extended to handle multiple constraints. Two passes of optimization are used to address both low-level and high-level constraints on the camera path. The experimental and user study results show that our approach outputs video that is perceptually better than the input, or the results of using stabilization only.

  9. Breastfeeding in HIV exposed infants significantly improves child health: a prospective study.

    Science.gov (United States)

    Kindra, Gurpreet; Coutsoudis, Anna; Esposito, Francesca; Esterhuizen, Tonya

    2012-04-01

    Breastfeeding has been shown to benefit both maternal and child immune status. The impact of exclusive breastfeeding in the presence of HIV infection on maternal and child health is still unclear. Socio-economic factors make breast-feeding an important source of nutrition for an infant 6 months and under in the developing world. A prospective study was conducted to examine the impact of feeding mode on various maternal indices including anthropometry; body composition indicators (using FTIR); haematology and biochemical markers; as well as incidence rates of opportunistic infections and clinical disease progression. In infants we examined the impact on growth, development and morbidity. AFASS criteria (affordable, feasible, accessible, sustainable and safe) were fulfilled by 38.7% of the formula feeding mothers. No significant differences between the formula feeding and breastfeeding groups in terms of haematological, immunological and body composition changes were seen. Breastfeeding mothers had significantly lower events with high depression scores (P = 0.043). Breastfeeding infants had a significantly lower risk of diarrhoea and hospitalisation at 3 months (P = 0.006 and 0.014 respectively). Breastfeeding was significantly associated with better development scores and growth parameters. Breastfeeding is not harmful to the mother in the presence of HIV infection. Mothers are still choosing formula feeding inappropriately despite counselling about the AFASS criteria. Breastfeeding is beneficial to the infants especially in the first 3 months of life.

  10. Nitrite addition to acidified sludge significantly improves digestibility, toxic metal removal, dewaterability and pathogen reduction

    Science.gov (United States)

    Du, Fangzhou; Keller, Jürg; Yuan, Zhiguo; Batstone, Damien J.; Freguia, Stefano; Pikaar, Ilje

    2016-12-01

    Sludge management is a major issue for water utilities globally. Poor digestibility and dewaterability are the main factors determining the cost for sludge management, whereas pathogen and toxic metal concentrations limit beneficial reuse. In this study, the effects of low level nitrite addition to acidified sludge to simultaneously enhance digestibility, toxic metal removal, dewaterability and pathogen reduction were investigated. Waste activated sludge (WAS) from a full-scale waste water treatment plant was treated at pH 2 with 10 mg NO2‑-N/L for 5 h. Biochemical methane potential tests showed an increase in the methane production of 28%, corresponding to an improvement from 247 ± 8 L CH4/kg VS to 317 ± 1 L CH4/kg VS. The enhanced removal of toxic metals further increased the methane production by another 18% to 360 ± 6 L CH4/kg VS (a total increase of 46%). The solids content of dewatered sludge increased from 14.6 ± 1.4% in the control to 18.2 ± 0.8%. A 4-log reduction for both total coliforms and E. coli was achieved. Overall, this study highlights the potential of acidification with low level nitrite addition as an effective and simple method achieving multiple improvements in terms of sludge management.

  11. Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Kutchenreiter, Mark; Michalski, J.J.; Long, C.N.; Habte, Aron

    2017-05-22

    Accurate solar radiation measurements using pyranometers are required to understand radiative impacts on the Earth's energy budget, solar energy production, and to validate radiative transfer models. Ventilators of pyranometers, which are used to keep the domes clean and dry, also affect instrument thermal offset accuracy. This poster presents a high-level overview of the ventilators for single-black-detector pyranometers and black-and-white pyranometers. For single-black-detector pyranometers with ventilators, high-flow-rate (50-CFM and higher), 12-V DC fans lower the offsets, lower the scatter, and improve the predictability of nighttime offsets compared to lower-flow-rate (35-CFM), 120-V AC fans operated in the same type of environmental setup. Black-and-white pyranometers, which are used to measure diffuse horizontal irradiance, sometimes show minor improvement with DC fan ventilation, but their offsets are always small, usually no more than 1 W/m2, whether AC- or DC-ventilated.

  12. Targeted agri-environment schemes significantly improve the population size of common farmland bumblebee species.

    Science.gov (United States)

    Wood, Thomas J; Holland, John M; Hughes, William O H; Goulson, Dave

    2015-04-01

    Changes in agricultural practice across Europe and North America have been associated with range contractions and local extinction of bumblebees (Bombus spp.). A number of agri-environment schemes have been implemented to halt and reverse these declines, predominantly revolving around the provision of additional forage plants. Although it has been demonstrated that these schemes can attract substantial numbers of foraging bumblebees, it remains unclear to what extent they actually increase bumblebee populations. We used standardized transect walks and molecular techniques to compare the size of bumblebee populations between Higher Level Stewardship (HLS) farms implementing pollinator-friendly schemes and Entry Level Stewardship (ELS) control farms. Bumblebee abundance on the transect walks was significantly higher on HLS farms than ELS farms. Molecular analysis suggested maximum foraging ranges of 566 m for Bombus hortorum, 714 m for B. lapidarius, 363 m for B. pascuorum and 799 m for B. terrestris. Substantial differences in maximum foraging range were found within bumblebee species between farm types. Accounting for foraging range differences, B. hortorum (47 vs 13 nests/km(2) ) and B. lapidarius (45 vs 22 nests/km(2) ) were found to nest at significantly greater densities on HLS farms than ELS farms. There were no significant differences between farm type for B. terrestris (88 vs 38 nests/km(2) ) and B. pascuorum (32 vs 39 nests/km(2) ). Across all bumblebee species, HLS management had a significantly positive effect on bumblebee nest density. These results show that targeted agri-environment schemes that increase the availability of suitable forage can significantly increase the size of wild bumblebee populations.

  13. A Review of Research on Improvement and Optimization of Performance Measures for Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    C. R. Sanghani

    2014-01-01

    Full Text Available Electrical Discharge Machining (EDM is a non conventional machining method which can be used to machine electrically conductive work pieces irrespective of their shape, hardness and toughness. High cost of non conventional machine tools, compared to conventional machining, has forced us to operate these machines as efficiently as possible in order to reduce production cost and to obtain the required reimbursement. To achieve this task, machining parameters such as pulse on time, pulse off time, discharge current, gap voltage, flushing pressure, electrode material, etc. of this process should be selected such that optimal value of their performance measures like Material Removal Rate (MRR, Surface Roughness (SR, Electrode/Tool Wear Rate (EWR/TWR, dimensional accuracy, etc. can be obtained or improved. In past decades, intensive research work had been carried out by different researchers for improvement and optimization of EDM performance measures using various optimization techniques like Taguchi, Response Surface Methodology (RSM, Artificial Neural Network (ANN, Genetic Algorithm (GA, etc. This paper reviews research on improvement and optimization of various performance measures of spark erosion EDM and finally lists down certain areas that can be taken up for further research in the field of improvement and optimization for EDM process.

  14. Quantum chemistry calculation-aided structural optimization of combretastatin A-4-like tubulin polymerization inhibitors: improved stability and biological activity.

    Science.gov (United States)

    Jiang, Junhang; Zheng, Canhui; Zhu, Kongkai; Liu, Jia; Sun, Nannan; Wang, Chongqing; Jiang, Hualiang; Zhu, Ju; Luo, Cheng; Zhou, Youjun

    2015-03-12

    A potent combretastatin A-4 (CA-4) like tubulin polymerization inhibitor 22b was found with strong antitumor activity previously. However, it easily undergoes cis-trans isomerization under natural light, and the resulting decrease in activity limits its further applications. In this study, we used quantum chemistry calculations to explore the molecular basis of its instability. Aided by the calculations, two rounds of structural optimization of 22b were conducted. Accelerated quantitative light stability testing confirmed that the stability of these designed compounds was significantly improved as predicted. Among them, compounds 1 and 3b displayed more potent inhibitory activity on tumor cell growth than 22b. In addition, the potent in vivo antitumor activity of compound 1 was confirmed. Quantum chemistry calculations were used in the optimization of stilbene-like molecules, providing new insight into stilbenoid optimization and important implications for the future development of novel CA-4-like tubulin polymerization inhibitors.

  15. Improved design and optimization of subsurface flow constructed wetlands and sand filters

    Science.gov (United States)

    Brovelli, A.; Carranza-Díaz, O.; Rossi, L.; Barry, D. A.

    2010-05-01

    Subsurface flow constructed wetlands and sand filters are engineered systems capable of eliminating a wide range of pollutants from wastewater. These devices are easy to operate, flexible and have low maintenance costs. For these reasons, they are particularly suitable for small settlements and isolated farms and their use has substantially increased in the last 15 years. Furthermore, they are also becoming used as a tertiary - polishing - step in traditional treatment plants. Recent work observed that research is however still necessary to understand better the biogeochemical processes occurring in the porous substrate, their mutual interactions and feedbacks, and ultimately to identify the optimal conditions to degrade or remove from the wastewater both traditional and anthropogenic recalcitrant pollutants, such as hydrocarbons, pharmaceuticals, personal care products. Optimal pollutant elimination is achieved if the contact time between microbial biomass and the contaminated water is sufficiently long. The contact time depends on the hydraulic residence time distribution (HRTD) and is controlled by the hydrodynamic properties of the system. Previous reports noted that poor hydrodynamic behaviour is frequent, with water flowing mainly through preferential paths resulting in a broad HRTD. In such systems the flow rate must be decreased to allow a sufficient proportion of the wastewater to experience the minimum residence time. The pollutant removal efficiency can therefore be significantly reduced, potentially leading to the failure of the system. The aim of this work was to analyse the effect of the heterogeneous distribution of the hydraulic properties of the porous substrate on the HRTD and treatment efficiency, and to develop an improved design methodology to reduce the risk of system failure and to optimize existing systems showing poor hydrodynamics. Numerical modelling was used to evaluate the effect of substrate heterogeneity on the breakthrough curves of

  16. Adaptive control schemes for improving dynamic performance of efficiency-optimized induction motor drives.

    Science.gov (United States)

    Kumar, Navneet; Raj Chelliah, Thanga; Srivastava, S P

    2015-07-01

    Model Based Control (MBC) is one of the energy optimal controllers used in vector-controlled Induction Motor (IM) for controlling the excitation of motor in accordance with torque and speed. MBC offers energy conservation especially at part-load operation, but it creates ripples in torque and speed during load transition, leading to poor dynamic performance of the drive. This study investigates the opportunity for improving dynamic performance of a three-phase IM operating with MBC and proposes three control schemes: (i) MBC with a low pass filter (ii) torque producing current (iqs) injection in the output of speed controller (iii) Variable Structure Speed Controller (VSSC). The pre and post operation of MBC during load transition is also analyzed. The dynamic performance of a 1-hp, three-phase squirrel-cage IM with mine-hoist load diagram is tested. Test results are provided for the conventional field-oriented (constant flux) control and MBC (adjustable excitation) with proposed schemes. The effectiveness of proposed schemes is also illustrated for parametric variations. The test results and subsequent analysis confer that the motor dynamics improves significantly with all three proposed schemes in terms of overshoot/undershoot peak amplitude of torque and DC link power in addition to energy saving during load transitions.

  17. Significantly improved HIV inhibitor efficacy prediction employing proteochemometric models generated from antivirogram data.

    Directory of Open Access Journals (Sweden)

    Gerard J P van Westen

    Full Text Available Infection with HIV cannot currently be cured; however it can be controlled by combination treatment with multiple anti-retroviral drugs. Given different viral genotypes for virtually each individual patient, the question now arises which drug combination to use to achieve effective treatment. With the availability of viral genotypic data and clinical phenotypic data, it has become possible to create computational models able to predict an optimal treatment regimen for an individual patient. Current models are based only on sequence data derived from viral genotyping; chemical similarity of drugs is not considered. To explore the added value of chemical similarity inclusion we applied proteochemometric models, combining chemical and protein target properties in a single bioactivity model. Our dataset was a large scale clinical database of genotypic and phenotypic information (in total ca. 300,000 drug-mutant bioactivity data points, 4 (NNRTI, 8 (NRTI or 9 (PI drugs, and 10,700 (NNRTI 10,500 (NRTI or 27,000 (PI mutants. Our models achieved a prediction error below 0.5 Log Fold Change. Moreover, when directly compared with previously published sequence data, derived models PCM performed better in resistance classification and prediction of Log Fold Change (0.76 log units versus 0.91. Furthermore, we were able to successfully confirm both known and identify previously unpublished, resistance-conferring mutations of HIV Reverse Transcriptase (e.g. K102Y, T216M and HIV Protease (e.g. Q18N, N88G from our dataset. Finally, we applied our models prospectively to the public HIV resistance database from Stanford University obtaining a correct resistance prediction rate of 84% on the full set (compared to 80% in previous work on a high quality subset. We conclude that proteochemometric models are able to accurately predict the phenotypic resistance based on genotypic data even for novel mutants and mixtures. Furthermore, we add an applicability domain to

  18. An improved flower pollination algorithm with chaos theory for function optimization

    Science.gov (United States)

    Pauline, Ong; Meng, Ong Kok; Kiong, Sia Chee

    2017-08-01

    Flower pollination algorithm (FPA) is one of the newly developed bio-inspired optimization approaches, inspiring by the flower pollination process. In this study, an improved FPA was developed, in which the utilization of the chaos theory was performed, such that the variety of the initial population was enhanced. Ten different chaotic maps were considered, and various benchmark functions were employed to validate the performance of the chaotic FPA. Comparison results indicated that integration of the FPA with chaos theory led to improvement in terms of convergence characteristic, where the Circle chaotic map gave the best optimization performance.

  19. Improved step-by-step chromaticity compensation method for chromatic sextupole optimization

    CERN Document Server

    Liu, Gang-Wen; Jia, Qi-Ka; Li, Wei-Min; Wang, Lin

    2015-01-01

    The step-by-step chromaticity compensation method for chromatic sextupole optimization and dynamic aperture increase was proposed by E. Levichev and P. Piminov (E. Levichev and P. Piminov, 2006 [1]). Although this method can be used to enlarge the dynamic aperture of storage ring, it has some drawbacks. In this paper, we combined this method with evolutionary computation algorithms, and proposed an improved version of this method. In the improved method, the drawbacks are avoided, and thus better optimization results can be obtained.

  20. Significantly improved survival time in pigs with complete liver ischemia treated with a novel bioartificial liver.

    Science.gov (United States)

    Flendrig, L M; Calise, F; Di Florio, E; Mancini, A; Ceriello, A; Santaniello, W; Mezza, E; Sicoli, F; Belleza, G; Bracco, A; Cozzolino, S; Scala, D; Mazzone, M; Fattore, M; Gonzales, E; Chamuleau, R A

    1999-10-01

    Aim of the study was to evaluate treatment efficacy and safety of a scaled-up version of our porcine hepatocytes based BAL system in pigs with complete liver ischemia (LIS). Thirty-one pigs underwent total devascularization of the liver (LIS) by termino-lateral porta-caval shunts and sutures around the bile duct, the common hepatic and gastroduodenal arteries and their accessory branches. The hepato-duodenal ligament was completely transected. Four experimental groups were studied: the first control group (LIS Control, n = 10) received glucose infusion only, the second control group (LIS Plasmapheresis, n = 8) was connected to a centrifugal plasma-separator with a bottle representing the bioreactor volume, the third control group (LIS Empty-BAL, n = 5) received BAL treatment without cells, and the treated group (LIS Cell-BAL, n = 8) was connected for a maximum period of 24 hours to our scaled-up BAL seeded with around 14 billion viable primary porcine hepatocytes. BAL treatment significantly prolonged life in large animals (approximately 35 kg) with complete LIS (Controls, mean +/- SEM: 33.1 +/- 3 h, Cell-BAL: 51.1 +/- 3.4 h; p = 0.001; longest survivor 63 h). In addition, blood ammonia and total bilirubin levels decreased significantly, indicating metabolic activity of porcine hepatocytes in the bioreactor. No significant differences were noticed among the three control groups, indicating that there was no device effect and that the plasmapheresis procedure was well tolerated. No important adverse effects were observed.

  1. Hypoxic-Preconditioned Bone Marrow Stem Cell Medium Significantly Improves Outcome After Retinal Ischemia in Rats.

    Science.gov (United States)

    Roth, Steven; Dreixler, John C; Mathew, Biji; Balyasnikova, Irina; Mann, Jacob R; Boddapoti, Venkat; Xue, Lai; Lesniak, Maciej S

    2016-06-01

    We have previously demonstrated the protective effect of bone marrow stem cell (BMSC)-conditioned medium in retinal ischemic injury. We hypothesized here that hypoxic preconditioning of stem cells significantly enhances the neuroprotective effect of the conditioned medium and thereby augments the protective effect in ischemic retina. Rats were subjected to retinal ischemia by increasing intraocular pressure to 130 to 135 mm Hg for 55 minutes. Hypoxic-preconditioned, hypoxic unconditioned, or normoxic medium was injected into the vitreous 24 hours after ischemia ended. Recovery was assessed 7 days after injections by comparing electroretinography measurements, histologic examination, and apoptosis (TUNEL, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay). To compare proteins secreted into the medium in the groups and the effect of hypoxic exposure, we used rat cytokine arrays. Eyes injected with hypoxic BMSC-conditioned medium 24 hours after ischemia demonstrated significantly enhanced return of retinal function, decreased retinal ganglion cell layer loss, and attenuated apoptosis compared to those administered normoxic or hypoxic unconditioned medium. Hypoxic-preconditioned medium had 21 significantly increased protein levels compared to normoxic medium. The medium from hypoxic-preconditioned BMSCs robustly restored retinal function and prevented cell loss after ischemia when injected 24 hours after ischemia. The protective effect was even more pronounced than in our previous studies of normoxic conditioned medium. Prosurvival signals triggered by the secretome may play a role in this neuroprotective effect.

  2. An improved method to set significance thresholds forβdiversity testing in microbial community comparisons

    DEFF Research Database (Denmark)

    Gülay, Arda; Smets, Barth F.

    2015-01-01

    -community. The proposed technique was applied to several in silico generated operational taxonomic unit (OTU) libraries and experimental 16S rRNA pyrosequencing libraries. The latter represented microbial communities from different biological rapid sand filters at a full-scale waterworks. We observe that β diversity......, after subsampling, is inflated by intra-sample differences; this inflation is avoided in the proposed method. In addition, microbial community evenness (Gini > 0.08) strongly affects all β diversity estimations due to bias associated with rarefaction. Where published methods to test β significance often...

  3. "Passive-bending colonoscope" significantly improves cecal intubation in difficult cases

    Institute of Scientific and Technical Information of China (English)

    Takeshi Mizukami; Haruhiko Ogata; Toshihumi Hibi

    2012-01-01

    Colonoscopy sometimes causes pain during insertion,especially in difficult cases.Over-insufflation of air causes elongation or acute angulations of the colon,making passage of the scope difficult and causing pain.We previously reported a sedative-risk-free colonoscopy insertion technique,namely,"Water Navigation Colonoscopy".Complete air suction after water infusion not only improves the vision,but also makes water flow down to the descending colon,while the sigmoid colon collapses and shortens.While non-sedative colonoscopy can be carried out without pain in most cases,some patients do complain of pain.Most of these patients have abnormal colon morphology,and the pain is caused while negotiating the "hairpin" bends of the colon.The "hairpin" bends of the colon should be negotiated by gently pushing the full-angled colonoscope.The proximal 10-20 cm from the angulated part of the conventional colonoscope is stiff,with a wide turning radius,therefore,a conventional colonoscope cannot be negotiated through the "hairpin" bends of the colon without stretching them and causing pain.The "passive-bending colonoscope" has a flexible tip with a narrow turning radius,so that the scope can be negotiated through the "hairpin" bends of the colon with a minimum turning radius and minimal discomfort.Therefore,the intubation and pain-reducing performance of the "passive-bending colonoscope" was assessed in difficult cases.

  4. Improving reducibility of iron ore pellets by optimization of physical parameters

    Directory of Open Access Journals (Sweden)

    Pal J.

    2017-01-01

    Full Text Available Reducibility of iron bearing material is an important property which represents its suitability of reduction in iron making furnaces. It has direct influence on improving productivity and lowering energy consumption in iron making process. The reducibility of iron ore pellets of a specific chemistry can be improved by the optimization of physical parameters such as induration temperature, improving size distribution of fines, improving apparent porosity etc. In this study, the reference pellet is prepared in a typical plant condition and the properties of the reference pellet are considered as base value to improve reducibility index (RI maintaining other properties at the acceptable limit without altering pellet chemistry. Optimization of induration temperature at the 1250-1275ºC shows around 74 % RI, which is 5 points more than the base value of 69.5 %. Furthermore, on optimizing additives size, such as limestone fines and anthracite coal fines at -350 mesh and induration temperature of 1250-1275ºC, RI is improved to 77 %, i.e., 8 points improvement is achieved with respect to the base value.

  5. Using optimized wall section to improve low frequency response in a room

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiaotian; ZHU Zhemin; CHENG Jianchun

    2006-01-01

    Three different wall sections with step shape were applied in the finite element analysis models set up to investigate the effect on low frequency sound field by wall modification.The heights of the step in three cases are taken as equal, random and optimized. The optimized value is obtained by using an optimization process with an objective function of minimum fluctuation in sound field. The frequency responses of rooms with original and modified walls were calculated in a range from 60 Hz to 120 Hz. The results showed that the room with an optimized wall section had the flattest frequency response. Same thing was true as the ratio of the room was changed. The largest improvement on fluctuation reached 4.5 dB. In addition, wall section with semicircle and triangle were studied. The rooms that wall section had optimized radius and heights also gave a better performance than those that had fixed radius and heights.Therefore, it is possible to use optimized wall section to improve low frequency sound field.

  6. Optimization on the impeller of a low-specific-speed centrifugal pump for hydraulic performance improvement

    Science.gov (United States)

    Pei, Ji; Wang, Wenjie; Yuan, Shouqi; Zhang, Jinfeng

    2016-09-01

    In order to widen the high-efficiency operating range of a low-specific-speed centrifugal pump, an optimization process for considering efficiencies under 1.0 Q d and 1.4 Q d is proposed. Three parameters, namely, the blade outlet width b 2, blade outlet angle β 2, and blade wrap angle φ, are selected as design variables. Impellers are generated using the optimal Latin hypercube sampling method. The pump efficiencies are calculated using the software CFX 14.5 at two operating points selected as objectives. Surrogate models are also constructed to analyze the relationship between the objectives and the design variables. Finally, the particle swarm optimization algorithm is applied to calculate the surrogate model to determine the best combination of the impeller parameters. The results show that the performance curve predicted by numerical simulation has a good agreement with the experimental results. Compared with the efficiencies of the original impeller, the hydraulic efficiencies of the optimized impeller are increased by 4.18% and 0.62% under 1.0 Q d and 1.4Qd, respectively. The comparison of inner flow between the original pump and optimized one illustrates the improvement of performance. The optimization process can provide a useful reference on performance improvement of other pumps, even on reduction of pressure fluctuations.

  7. Significant improvement in Mn2O3 transition metal oxide electrical conductivity via high pressure

    Science.gov (United States)

    Hong, Fang; Yue, Binbin; Hirao, Naohisa; Liu, Zhenxian; Chen, Bin

    2017-01-01

    Highly efficient energy storage is in high demand for next-generation clean energy applications. As a promising energy storage material, the application of Mn2O3 is limited due to its poor electrical conductivity. Here, high-pressure techniques enhanced the electrical conductivity of Mn2O3 significantly. In situ synchrotron micro X-Ray diffraction, Raman spectroscopy and resistivity measurement revealed that resistivity decreased with pressure and dramatically dropped near the phase transition. At the highest pressure, resistivity reduced by five orders of magnitude and the sample showed metal-like behavior. More importantly, resistivity remained much lower than its original value, even when the pressure was fully released. This work provides a new method to enhance the electronic properties of Mn2O3 using high-pressure treatment, benefiting its applications in energy-related fields. PMID:28276479

  8. Significant improvement of pig cloning efficiency by treatment with LBH589 after somatic cell nuclear transfer.

    Science.gov (United States)

    Jin, Jun-Xue; Li, Suo; Gao, Qing-Shan; Hong, Yu; Jin, Long; Zhu, Hai-Ying; Yan, Chang-Guo; Kang, Jin-Dan; Yin, Xi-Jun

    2013-10-01

    The low success rate of animal cloning by somatic cell nuclear transfer (SCNT) associates with epigenetic aberrancy, including the abnormal acetylation of histones. Altering the epigenetic status by histone deacetylase inhibitors (HDACi) enhances the developmental potential of SCNT embryos. In the current study, we examined the effects of LBH589 (panobinostat), a novel broad-spectrum HDACi, on the nuclear reprogramming and development of pig SCNT embryos in vitro. In experiment 1, we compared the in vitro developmental competence of nuclear transfer embryos treated with different concentrations of LBH589. Embryos treated with 50 nM LBH589 for 24 hours showed a significant increase in the rate of blastocyst formation compared with the control or embryos treated with 5 or 500 nM LBH589 (32.4% vs. 11.8%, 12.1%, and 10.0%, respectively, P < 0.05). In experiment 2, we examined the in vitro developmental competence of nuclear transfer embryos treated with 50 nM LBH589 for various intervals after activation and 6-dimethylaminopurine. Embryos treated for 24 hours had higher rates of blastocyst formation than the other groups. In experiment 3, when the acetylation of H4K12 was examined in SCNT embryos treated for 6 hours with 50 nM LBH589 by immunohistochemistry, the staining intensities of these proteins in LBH589-treated SCNT embryos were significantly higher than in the control. In experiment 4, LBH589-treated nuclear transfer and control embryos were transferred into surrogate mothers, resulting in three (100%) and two (66.7%) pregnancies, respectively. In conclusion, LBH589 enhances the nuclear reprogramming and developmental potential of SCNT embryos by altering the epigenetic status and expression, and increasing blastocyst quality.

  9. Bayesian Species Identification under the Multispecies Coalescent Provides Significant Improvements to DNA Barcoding Analyses.

    Science.gov (United States)

    Yang, Ziheng; Rannala, Bruce

    2017-03-09

    DNA barcoding methods use a single locus (usually the mitochondrial COI gene) to assign unidentified specimens to known species in a library based on a genetic distance threshold that distinguishes between-species divergence from within-species diversity. Recently developed species delimitation methods based on the multispecies coalescent (MSC) model offer an alternative approach to individual assignment using either single-locus or multi-loci sequence data. Here we use simulations to demonstrate three features of an MSC method implemented in the program bpp. First, we show that with one locus, MSC can accurately assign individuals to species without the need for arbitrarily determined distance thresholds (as required for barcoding methods). We provide an example in which no single threshold or barcoding gap exists that can be used to assign all specimens without incurring high error rates. Second, we show that bpp can identify cryptic species that may be mis-identified as a single species within the library, potentially improving the accuracy of barcoding libraries. Third, we show that taxon rarity does not present any particular problems for species assignments using bpp, and that accurate assignments can be achieved even when only one or a few loci are available. Thus, concerns that have been raised that MSC methods may have problems analyzing rare taxa (singletons) are unfounded. Currently barcoding methods enjoy a huge computational advantage over MSC methods and may be the only approach feasible for massively large datasets, but MSC methods may offer a more stringent test for species that are tentatively assigned by barcoding. This article is protected by copyright. All rights reserved.

  10. Distribution Grid Reactive Power Optimization Based on Improved Cloud Particle Swarm Algorithm

    Directory of Open Access Journals (Sweden)

    Hongsheng Su

    2013-01-01

    Full Text Available To resolve the problems that cloud particle swarm optimization(CPSO was easily trapped in local minimum and possessed slow convergence speed and early-maturing during distribution grid reactive power optimization, CPSO algorithm was improved based on cloud digital features in this paper. The method firstly combined Local search with global search together based on solution space transform, where the crossover and mutation operation of the particles were implemented based on normal cloud operator. And then the dramatic achievements were acquired in time-consuming and storage-cost using the improved algorithm. Finally, applied in bus IEEE30 system, the simulation results show that the better global solution is attained using the improved CPSO algorithm, and its convergence speed and accuracy possesses a dramatic improvement.

  11. Omega-3 fatty acid therapy dose-dependently and significantly decreased triglycerides and improved flow-mediated dilation, however, did not significantly improve insulin sensitivity in patients with hypertriglyceridemia.

    Science.gov (United States)

    Oh, Pyung Chun; Koh, Kwang Kon; Sakuma, Ichiro; Lim, Soo; Lee, Yonghee; Lee, Seungik; Lee, Kyounghoon; Han, Seung Hwan; Shin, Eak Kyun

    2014-10-20

    Experimental studies demonstrate that higher intake of omega-3 fatty acids (n-3 FA) improves insulin sensitivity, however, we reported that n-3 FA 2g therapy, most commonly used dosage did not significantly improve insulin sensitivity despite reducing triglycerides by 21% in patients. Therefore, we investigated the effects of different dosages of n-3 FA in patients with hypertriglyceridemia. This was a randomized, single-blind, placebo-controlled, parallel study. Age, sex, and body mass index were matched among groups. All patients were recommended to maintain a low fat diet. Forty-four patients (about 18 had metabolic syndrome/type 2 diabetes mellitus) in each group were given placebo, n-3 FA 1 (O1), 2 (O2), or 4 g (O4), respectively daily for 2 months. n-3 FA therapy dose-dependently and significantly decreased triglycerides and triglycerides/HDL cholesterol and improved flow-mediated dilation, compared with placebo (by ANOVA). However, each n-3 FA therapy did not significantly decrease high-sensitivity C-reactive protein and fibrinogen, compared with placebo. O1 significantly increased insulin levels and decreased insulin sensitivity (determined by QUICKI) and O2 significantly decreased plasma adiponectin levels relative to baseline measurements. Of note, when compared with placebo, each n-3 FA therapy did not significantly change insulin, glucose, adiponectin, glycated hemoglobin levels and insulin sensitivity (by ANOVA). We observed similar results in a subgroup of patients with the metabolic syndrome. n-3 FA therapy dose-dependently and significantly decreased triglycerides and improved flow-mediated dilation. Nonetheless, n-3 FA therapy did not significantly improve acute-phase reactants and insulin sensitivity in patients with hypertriglyceridemia, regardless of dosages. Copyright © 2014. Published by Elsevier Ireland Ltd.

  12. Improved Data Transmission Scheme of Network Coding Based on Access Point Optimization in VANET

    Directory of Open Access Journals (Sweden)

    Zhe Yang

    2014-01-01

    Full Text Available VANET is a hot spot of intelligent transportation researches. For vehicle users, the file sharing and content distribution through roadside access points (AP as well as the vehicular ad hoc networks (VANET have been an important complement to that cellular network. So the AP deployment is one of the key issues to improve the communication performance of VANET. In this paper, an access point optimization method is proposed based on particle swarm optimization algorithm. The transmission performances of the routing protocol with random linear network coding before and after the access point optimization are analyzed. The simulation results show the optimization model greatly affects the VANET transmission performances based on network coding, and it can enhance the delivery rate by 25% and 14% and reduce the average delay of transmission by 38% and 33%.

  13. Improving the Hydraulic Efficiency of Centrifugal Pumps through Computational Fluid Dynamics Based Design optimization

    Directory of Open Access Journals (Sweden)

    Abdellah Ait moussa

    2014-08-01

    Full Text Available The design and optimization of turbo machine impellers such as those in pumps and turbines is a highly complicated task due to the complex three-dimensional shape of the impeller blades and surrounding devices. Small differences in geometry can lead to significant changes in the performance of these machines. We report here an efficient numerical technique that automatically optimizes the geometry of these blades for maximum performance. The technique combines, mathematical modeling of the impeller blades using non-uniform rational B-spline (NURBS, Computational fluid dynamics (CFD with Geometry Parameterizations in turbulent flow simulation and the Globalized and bounded Nelder-Mead (GBNM algorithm in geometry optimization.

  14. Study on Optimal Placement and Reasonable Number of Viscoelastic Dampers by Improved Weight Coefficient Method

    Directory of Open Access Journals (Sweden)

    Ji-ting Qu

    2013-01-01

    Full Text Available A new optimal method is presented by combining the weight coefficient with the theory of force analogy method. Firstly, a new mathematical model of location index is proposed, which deals with the determination of a reasonable number of dampers according to values of the location index. Secondly, the optimal locations of dampers are given. It can be specific from stories to spans. Numerical examples are illustrated to verify the effectiveness and feasibility of the proposed mathematical model and optimal method. At last, several significant conclusions are given based on numerical results.

  15. Optimizing MRI Logistics: Focused Process Improvements Can Increase Throughput in an Academic Radiology Department.

    Science.gov (United States)

    O'Brien, Jeremy J; Stormann, Jeremy; Roche, Kelli; Cabral-Goncalves, Ines; Monks, Annamarie; Hallett, Donna; Mortele, Koenraad J

    2017-02-01

    The purpose of this study was to describe and evaluate the effect of focused process improvements on protocol selection and scheduling in the MRI division of a busy academic medical center, as measured by examination and room times, magnet fill rate, and potential revenue increases and cost savings to the department. Focused process improvements, led by a multidisciplinary team at a large academic medical center, were directed at streamlining MRI protocols and optimizing matching protocol ordering to scheduling while maintaining or improving image quality. Data were collected before (June 2013) and after (March 2015) implementation of focused process improvements and divided by subspecialty on type of examination, allotted examination time, actual examination time, and MRI parameters. Direct and indirect costs were compiled and analyzed in consultation with the business department. Data were compared with evaluated effects on selected outcome and efficiency measures, as well as revenue and cost considerations. Statistical analysis was performed using a t test. During the month of June 2013, 2145 MRI examinations were performed at our center; 2702 were performed in March 2015. Neuroradiology examinations were the most common (59% in June 2013, 56% in March 2015), followed by body examinations (25% and 27%). All protocols and parameters were analyzed and streamlined for each examination, with slice thickness, TR, and echo train length among the most adjusted parameters. Mean time per examination decreased from 43.4 minutes to 36.7 minutes, and mean room time per patient decreased from 46.3 to 43.6 minutes (p = 0.009). Potential revenue from increased throughput may yield up to $3 million yearly (at $800 net revenue per scan) or produce cost savings if the facility can reduce staffed scanner hours or the number of scanners in its fleet. Actual revenue and expense impacts depend on the facility's fixed and variable cost structure, payer contracts, MRI fleet composition

  16. The Strasbourg Large Refractor and Dome: Significant Improvements and Failed Attempts

    Science.gov (United States)

    Heck, Andre

    2009-01-01

    Founded by the German Empire in the late 19th century, Strasbourg Astronomical Observatory featured several novelties from the start. According to Mueller (1978), the separation of observing buildings from the study area and from the astronomers' residence was a revolution in observatory construction. The instruments were, as much as possible, isolated from the vibrations of the buildings themselves. "Gas flames" and water were used to reduce temperature effects. Thus the Large Dome (ca 11m diameter), housing the Large Refractor (ca 49cm, then the largest in Germany) and covered by zinc over wood, could be cooled down by water running from the top. Reports (including by the French who took over the observatory after World War I) are however somehow nonexistent on the effective usage and actual efficiency of such a system (which must have generated locally a significant amount of humidity). The paper will detail these technical attempts as well as the specificities of the instruments installed in that new observatory intended as a showcase of German astronomy.

  17. Improved Sugar Production by Optimizing Planetary Mill Pretreatment and Enzyme Hydrolysis Process

    Directory of Open Access Journals (Sweden)

    Jeong Heo Kwon

    2015-01-01

    Full Text Available This paper describes an optimization of planetary mill pretreatment and saccharification processes for improving biosugar production. Pitch pine (Pinus rigida wood sawdust waste was used as biomass feedstock and the process parameters optimized in this study were the buffering media, the milling time, the enzyme quantity, and the incubation time. Glucose yields were improved when acetate buffer was used rather than citrate buffer. Initially, with each process variable tests, the optimal values were 100 minutes of milling, an enzyme concentration of 16 FPU/g-biomass, and a 12-hour enzymatic hydrolysis. Typically, interactions between these experimental conditions and their effects on glucose production were next investigated using RSM. Glucose yields from the Pinus rigida waste exceeded 80% with several of the conditions tested, demonstrating that milling can be used to obtain high levels of glucose bioconversion from woody biomass for biorefinery purposes.

  18. Optimization of Boiler Control for Improvement of Load Following Capabilities of Existing Power Plants

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Pedersen, Tom Søndergaard

    1997-01-01

    An An optimizing control system for improving the load following capabilities of power plant units has been developed. The system is implemented as a complement producing additive control signals to the existing boiler control system, a concept which has various practical advantages in terms...... of implementation and commissioning. The optimizing control system takes into account the multivariable and nonlinear characteristics of the boiler process as a gain-scheduled LQG-controller is utilized. Simulation results indicate that a reduction of steam temperature deviations of about 75% can be obtained.......optimizing control system for improving the load following capabilities of power plant units has been developed. The system is implemented as a complement producing additive control signals to the existing boiler control system, a concept which has various practical advantages in terms of implementation...

  19. An Improved Fruit Fly Optimization Algorithm Inspired from Cell Communication Mechanism

    Directory of Open Access Journals (Sweden)

    Chuncai Xiao

    2015-01-01

    Full Text Available Fruit fly optimization algorithm (FOA invented recently is a new swarm intelligence method based on fruit fly’s foraging behaviors and has been shown to be competitive with existing evolutionary algorithms, such as particle swarm optimization (PSO algorithm. However, there are still some disadvantages in the FOA, such as low convergence precision, easily trapped in a local optimum value at the later evolution stage. This paper presents an improved FOA based on the cell communication mechanism (CFOA, by considering the information of the global worst, mean, and best solutions into the search strategy to improve the exploitation. The results from a set of numerical benchmark functions show that the CFOA outperforms the FOA and the PSO in most of the experiments. Further, the CFOA is applied to optimize the controller for preoxidation furnaces in carbon fibers production. Simulation results demonstrate the effectiveness of the CFOA.

  20. Opposition-Based Improved PSO for Optimal Reactive Power Dispatch and Voltage Control

    Directory of Open Access Journals (Sweden)

    Shengrang Cao

    2015-01-01

    Full Text Available An opposition-based improved particle swarm optimization algorithm (OIPSO is presented for solving multiobjective reactive power optimization problem. OIPSO uses the opposition learning to improve search efficiency, adopts inertia weight factors to balance global and local exploration, and takes crossover and mutation and neighborhood model strategy to enhance population diversity. Then, a new multiobjective model is built, which includes system network loss, voltage dissatisfaction, and switching operation. Based on the market cost prices, objective functions are converted to least-cost model. In modeling process, switching operation cost is described according to the life cycle cost of transformer, and voltage dissatisfaction penalty is developed considering different voltage quality requirements of customers. The experiment is done on the new mathematical model. Through the simulation of IEEE 30-, 118-bus power systems, the results prove that OIPSO is more efficient to solve reactive power optimization problems and the model is more accurate to reflect the real power system operation.

  1. Diesel Engine performance improvement in a 1-D engine model using Particle Swarm Optimization

    Science.gov (United States)

    Karra, Prashanth

    2015-12-01

    A particle swarm optimization (PSO) technique was implemented to improve the engine development and optimization process to simultaneously reduce emissions and improve the fuel efficiency. The optimization was performed on a 4-stroke 4-cylinder GT-Power based 1-D diesel engine model. To achieve the multi-objective optimization, a merit function was defined which included the parameters to be optimized: Nitrogen Oxides (NOx), Nonmethyl hydro carbons (NMHC), Carbon Monoxide (CO), Brake Specific Fuel Consumption (BSFC). EPA Tier 3 emissions standards for non-road diesel engines between 37 and 75 kW of output were chosen as targets for the optimization. The combustion parameters analyzed in this study include: Start of main Injection, Start of Pilot Injection, Pilot fuel quantity, Swirl, and Tumble. The PSO was found to be very effective in quickly arriving at a solution that met the target criteria as defined in the merit function. The optimization took around 40-50 runs to find the most favourable engine operating condition under the constraints specified in the optimization. In a favourable case with a high merit function values, the NOx+NMHC and CO values were reduced to as low as 2.9 and 0.014 g/kWh, respectively. The operating conditions at this point were: 10 ATDC Main SOI, -25 ATDC Pilot SOI, 0.25 mg of pilot fuel, 0.45 Swirl and 0.85 tumble. These results indicate that late main injections preceded by a close, small pilot injection are most favourable conditions at the operating condition tested.

  2. A simple optimization can improve the performance of single feature polymorphism detection by Affymetrix expression arrays

    Directory of Open Access Journals (Sweden)

    Fujisawa Hironori

    2010-05-01

    Full Text Available Abstract Background High-density oligonucleotide arrays are effective tools for genotyping numerous loci simultaneously. In small genome species (genome size: Results We compared the single feature polymorphism (SFP detection performance of whole-genome and transcript hybridizations using the Affymetrix GeneChip® Rice Genome Array, using the rice cultivars with full genome sequence, japonica cultivar Nipponbare and indica cultivar 93-11. Both genomes were surveyed for all probe target sequences. Only completely matched 25-mer single copy probes of the Nipponbare genome were extracted, and SFPs between them and 93-11 sequences were predicted. We investigated optimum conditions for SFP detection in both whole genome and transcript hybridization using differences between perfect match and mismatch probe intensities of non-polymorphic targets, assuming that these differences are representative of those between mismatch and perfect targets. Several statistical methods of SFP detection by whole-genome hybridization were compared under the optimized conditions. Causes of false positives and negatives in SFP detection in both types of hybridization were investigated. Conclusions The optimizations allowed a more than 20% increase in true SFP detection in whole-genome hybridization and a large improvement of SFP detection performance in transcript hybridization. Significance analysis of the microarray for log-transformed raw intensities of PM probes gave the best performance in whole genome hybridization, and 22,936 true SFPs were detected with 23.58% false positives by whole genome hybridization. For transcript hybridization, stable SFP detection was achieved for highly expressed genes, and about 3,500 SFPs were detected at a high sensitivity (> 50% in both shoot and young panicle transcripts. High SFP detection performances of both genome and transcript hybridizations indicated that microarrays of a complex genome (e.g., of Oryza sativa can be

  3. An Improved Particle Swarm Optimization Based on Deluge Approach for Enhanced Hierarchical Cache Optimization in IPTV Networks

    Directory of Open Access Journals (Sweden)

    M. Somu

    2014-05-01

    Full Text Available In recent years, IP network has been considered as a new delivery network for TV services. A majority of the telecommunication industries have used IP network to offer on-demand services and linear TV services as it can offer a two-way and high-speed communication. In order to effectively and economically utilize the IP network, caching is the technique which is usually preferred. In IPTV system, a managed network is utilized to bring out TV services, the requests of Video on Demand (VOD objects are usually combined in a limited period intensively and user preferences are fluctuated dynamically. Furthermore, the VOD content updates often under the control of IPTV providers. In order to minimize this traffic and overall network cost, a segment of the video content is stored in caches closer to subscribers, for example, Digital Subscriber Line Access Multiplexer (DSLAM, a Central Office (CO and Intermediate Office (IO. The major problem focused in this approach is to determine the optimal cache memory that should be assigned in order to attain maximum cost effectiveness. This approach uses an effective Grate Deluge algorithm based Particle Swarm Optimization (GDPSO approach for attaining the optimal cache memory size which in turn minimizes the overall network cost. The analysis shows that hierarchical distributed caching can save significant network cost through the utilization of the GDPSO algorithm.

  4. Improvement of the Energy Resolution via an Optimized Digital Signal Processing in GERDA Phase I

    CERN Document Server

    Agostini, M; Bakalyarov, A M; Balata, M; Barabanov, I; Barros, N; Baudis, L; Bauer, C; Becerici-Schmidt, N; Bellotti, E; Belogurov, S; Belyaev, S T; Benato, G; Bettini, A; Bezrukov, L; Bode, T; Borowicz, D; Brudanin, V; Brugnera, R; Budjáš, D; Caldwell, A; Cattadori, C; Chernogorov, A; D'Andrea, V; Demidova, E V; di Vacri, A; Domula, A; Doroshkevich, E; Egorov, V; Falkenstein, R; Fedorova, O; Freund, K; Frodyma, N; Gangapshev, A; Garfagnini, A; Grabmayr, P; Gurentsov, V; Gusev, K; Hegai, A; Heisel, M; Hemmer, S; Heusser, G; Hofmann, W; Hult, M; Inzhechik, L V; Csáthy, J Janicskó; Jochum, J; Junker, M; Kazalov, V; Kihm, T; Kirpichnikov, I V; Kirsch, A; Klimenko, A; Knöpfle, K T; Kochetov, O; Kornoukhov, V N; Kuzminov, V V; Laubenstein, M; Lazzaro, A; Lebedev, V I; Lehnert, B; Liao, H Y; Lindner, M; Lippi, I; Lubashevskiy, A; Lubsandorzhiev, B; Lutter, G; Macolino, C; Majorovits, B; Maneschg, W; Medinaceli, E; Misiaszek, M; Moseev, P; Nemchenok, I; Palioselitis, D; Panas, K; Pandola, L; Pelczar, K; Pullia, A; Riboldi, S; Rumyantseva, N; Sada, C; Salathe, M; Schmitt, C; Schneider, B; Schönert, S; Schreiner, J; Schütz, A -K; Schulz, O; Schwingenheuer, B; Selivanenko, O; Shirchenko, M; Simgen, H; Smolnikov, A; Stanco, L; Stepaniuk, M; Ur, C A; Vanhoefer, L; Vasenko, A A; Veresnikova, A; von Sturm, K; Wagner, V; Walter, M; Wegmann, A; Wester, T; Wilsenach, H; Wojcik, M; Yanovich, E; Zavarise, P; Zhitnikov, I; Zhukov, S V; Zinatulina, D; Zuber, K; Zuzel, G

    2015-01-01

    An optimized digital shaping filter has been developed for the GERDA experiment which searches for neutrinoless double beta decay in 76Ge. The GERDA Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) at the 76Ge Q value for 0\

  5. Design of SVC Controller Based on Improved Biogeography-Based Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Feifei Dong

    2014-01-01

    Full Text Available Considering that common subsynchronous resonance controllers cannot adapt to the characteristics of the time-varying and nonlinear behavior of a power system, the cosine migration model, the improved migration operator, and the mutative scale of chaos and Cauchy mutation strategy are introduced into an improved biogeography-based optimization (IBBO algorithm in order to design an optimal subsynchronous damping controller based on the mechanism of suppressing SSR by static var compensator (SVC. The effectiveness of the improved controller is verified by eigenvalue analysis and electromagnetic simulations. The simulation results of Jinjie plant indicate that the subsynchronous damping controller optimized by the IBBO algorithm can remarkably improve the damping of torsional modes and thus effectively depress SSR, and ensure the safety and stability of units and power grid operation. Moreover, the IBBO algorithm has the merits of a faster searching speed and higher searching accuracy in seeking the optimal control parameters over traditional algorithms, such as BBO algorithm, PSO algorithm, and GA algorithm.

  6. An Improved Particle Swarm Optimization Algorithm with Harmony Strategy for the Location of Critical Slip Surface of Slopes

    Institute of Scientific and Technical Information of China (English)

    LI Liang; CHU Xue-song

    2011-01-01

    The determination of optimal values for three parameters required in the original particle swarm optimization algorithm is very difficult. It is proposed that two new parameters simulating the harmony search strategy can be adopted instead of the three parameters which are required in the original particle swarm optimization algorithm to update the positions of all the particles. The improved particle swarm optimization is used in the location of the critical slip surface of soil slope, and it is found that the improved particle swarm optimization algorithm is insensitive to the two parameters while the original particle swarm optimization algorithm can be sensitive to its three parameters.

  7. ABOUT OPTIMIZING OF INVESTMENT VOLUMES TO IMPROVE THE BASIC INDICATORS OF THE ENTERPRISE EFFECTIVENESS

    Directory of Open Access Journals (Sweden)

    Z. M. Gasanov

    2014-12-01

    Full Text Available Purpose. Profit and profitability of any, including transport enterprises are the main economic indicators of the enterprise effectiveness. These indicators reflect the results and successful performance of the enterprise. On the other hand the enterprise effectiveness in the long term, assurance of rapid development and competitiveness is largely determined by the level of investment activity and the range of investment activity. The purpose of this study is the feasibility of the method to determine optimal investments volume for improving these or others (selectable by the management principal economic indicators of the enterprise effectiveness. Methodology. The basis of the proposed methodology for determining the optimal investments volume is the theory of optimal control, in particular, the procedure of dynamic programming since a managed development process of the enterprise is a multiple stage. This procedure, using a phased plan, allows not only simplifying the solution of optimization problems, but also solving those, which are impossible to apply the methods of mathematical analysis. Findings. The expediency of performing the calculations to determine the optimal investments volume to ensure high rates of enterprise development was proved, it is a key to the effectiveness of the enterprise in the long term and it improves its competitiveness. Originality. It is shown that using methods of the optimum control theory one can calculate the minimum volume of capital investments for the improvement of economic indicators, which determine the enterprise effectiveness. The proposed method of calculation does not depend on the specific content of economic indicators. The effectiveness of this calculation method is demonstrated on a model example. Practical value. The proposed method of calculating the minimum volume of capital investments to improve the economic effectiveness of enterprises is quite simple, but at the same time enables, on

  8. Improved DQE by means of X-ray spectra and scintillator optimization for FFDM

    Science.gov (United States)

    Job, Isaias D.; Taie-Nobraie, Nima; Colbeth, Richard E.; Mollov, Ivan; Gray, Keith D.; Webb, Chris; Pavkovich, John M.; Zoghi, Fred; Tognina, Carlo A.; Roos, Pieter G.

    2012-03-01

    The focus of this work was to improve the DQE performance of a full-field digital mammography (FFDM) system by means of selecting an optimal X-ray tube anode-filter combination in conjunction with an optimal scintillator configuration. The flat panel detector in this work is a Varian PaxScan 3024M. The detector technology is comprised of a 2816 row × 3584 column amorphous silicon (a-Si) photodiode array with a pixel pitch of 83μm. The scintillator is cesium iodide and is deposited directly onto the photodiode array and available with configurable optical and x-ray properties. Two X-ray beam spectra were generated with the anode/filter combinations, Molybdenum/Molybdenum (Mo/Mo) and Tungsten/Aluminum (W/Al), to evaluate the imaging performance of two types of scintillators, high resolution (HR) type and high light output (HL) type. The results for the HR scintillator with W/Al anode-filter (HRW/ Al) yielded a DQE(0) of 67%, while HR-Mo/Mo was lower with a DQE(0) of 50%. In addition, the DQE(0) of the HR-W/Al configuration was comparable to the DQE(0) of the HL-Mo/Mo configuration. The significance of this result is the HR type scintillator yields about twice the light output with the W/Al spectrum, at about half the dose, as compared to the Mo/Mo spectrum. The light output or sensitivity was measured in analog-to-digital convertor units (ADU) per dose. The sensitivities (ADU/uGy) were 8.6, 16.8 and 25.4 for HR-Mo/Mo, HR-W/Al, HL-Mo/Mo, respectively. The Nyquist frequency for the 83 μm pixel is 6 lp/mm. The MTF at 5 lp/mm for HR-Mo/Mo and HR-W/Al were equivalent at 37%, while the HL-Mo/Mo MTF was 24%. According to the DQE metric, the more favorable anodefilter combination was W/Al with the HR scintillator. Future testing will evaluate the HL-W/Al configuration, as well as other x-ray filters materials and other scintillator optimizations. While higher DQE values were achieved, the more general conclusion is that the imaging performance can be tuned as required by

  9. Improvement of Power Flow Calculation with Optimization Factor Based on Current Injection Method

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2014-01-01

    Full Text Available This paper presents an improvement in power flow calculation based on current injection method by introducing optimization factor. In the method proposed by this paper, the PQ buses are represented by current mismatches while the PV buses are represented by power mismatches. It is different from the representations in conventional current injection power flow equations. By using the combined power and current injection mismatches method, the number of the equations required can be decreased to only one for each PV bus. The optimization factor is used to improve the iteration process and to ensure the effectiveness of the improved method proposed when the system is ill-conditioned. To verify the effectiveness of the method, the IEEE test systems are tested by conventional current injection method and the improved method proposed separately. Then the results are compared. The comparisons show that the optimization factor improves the convergence character effectively, especially that when the system is at high loading level and R/X ratio, the iteration number is one or two times less than the conventional current injection method. When the overloading condition of the system is serious, the iteration number in this paper appears 4 times less than the conventional current injection method.

  10. Improving Man-Optimal Stable Matchings by Minimum Change of Preference Lists

    Directory of Open Access Journals (Sweden)

    Shuichi Miyazaki

    2013-05-01

    Full Text Available In the stable marriage problem, any instance admits the so-called man-optimal stable matching, in which every man is assigned the best possible partner. However, there are instances for which all men receive low-ranked partners even in the man-optimal stable matching. In this paper we consider the problem of improving the man-optimal stable matching by changing only one man’s preference list. We show that the optimization variant and the decision variant of this problem can be solved in time O(n3 and O(n2, respectively, where n is the number of men (women in an input. We further extend the problem so that we are allowed to change k men’s preference lists. We show that the problem is W[1]-hard with respect to the parameter k and give O(n2k+1-time and O(nk+1-time exact algorithms for the optimization and decision variants, respectively. Finally, we show that the problems become easy when k = n; we give O(n2.5 log n-time and O(n2-time algorithms for the optimization and decision variants, respectively.

  11. Stiffener Layout Optimization of Inlet Structure for Electrostatic Precipitator by Improved Adaptive Growth Method

    Directory of Open Access Journals (Sweden)

    Jin Ji

    2014-11-01

    Full Text Available The inlet structure is the main part of an electrostatic precipitator, so its mechanical properties, including the static strength, stiffness, and vibration characteristics, play an important role in the structural safety. In order to achieve good mechanical performance and lightweight of the inlet structure, an optimal design method, which is based on growth mechanism of the branching systems in nature and optimality criteria, named the improved adaptive growth method, is suggested. The method is applied to optimize the stiffener layout of the inlet structure, and the multiobjective optimization mathematical model which consists of the minimum compliance and the maximum natural frequency is considered. The optimality criteria method is applied to solve the design problem. The design result shows that the suggested method is effective, compared with the empirical design of the inlet structure, the weight of the optimal structure is reduced by 3.0%, while the global stiffness and the first natural frequency are increased by 18.83% and 4.66%, respectively.

  12. Improved particle swarm optimization algorithm for android medical care IOT using modified parameters.

    Science.gov (United States)

    Sung, Wen-Tsai; Chiang, Yen-Chun

    2012-12-01

    This study examines wireless sensor network with real-time remote identification using the Android study of things (HCIOT) platform in community healthcare. An improved particle swarm optimization (PSO) method is proposed to efficiently enhance physiological multi-sensors data fusion measurement precision in the Internet of Things (IOT) system. Improved PSO (IPSO) includes: inertia weight factor design, shrinkage factor adjustment to allow improved PSO algorithm data fusion performance. The Android platform is employed to build multi-physiological signal processing and timely medical care of things analysis. Wireless sensor network signal transmission and Internet links allow community or family members to have timely medical care network services.

  13. Improved Optimization Study of Integration Strategies in Solar Aided Coal-Fired Power Generation System

    Directory of Open Access Journals (Sweden)

    Rongrong Zhai

    2015-01-01

    Full Text Available Solar aided coal-fired power generation system (SACFPGS combines solar energy and traditional coal-fired units in a particular way. This study mainly improves the solar thermal storage system. Genetic algorithm is used to optimize the SACFPGS. The best integration approach of the system, the collector area, and the corresponding thermal storage capacity to replace each high-pressure extraction are obtained when the amount of coal saving in unit solar investment per hour is at its largest. System performance before and after the improvement is compared. Results show that the improvement of the thermal storage system effectively increases the economic benefit of the integrated system.

  14. An Improved Particle Swarm Optimization Algorithm and Its Application in the Community Division

    Directory of Open Access Journals (Sweden)

    Jiang Hao

    2016-01-01

    Full Text Available With the deepening of the research on complex networks, the method of detecting and classifying social network is springing up. In this essay, the basic particle swarm algorithm is improved based on the GN algorithm. Modularity is taken as a measure of community division [1]. In view of the dynamic network community division, scrolling calculation method is put forward. Experiments show that using the improved particle swarm optimization algorithm can improve the accuracy of the community division and can also get higher value of the modularity in the dynamic community

  15. OPTIMIZING LIFESTYLE IMPROVES GLYCEMIC PROFILE IN PATIENTS AT RISK FOR DIABETES MELLITUS

    Directory of Open Access Journals (Sweden)

    Rucsandra Dănciulescu Miulescu

    2009-10-01

    Full Text Available There is a pandemic of type 2 diabetes mellitus due to urban and sedentary lifestyle, ageing and obesity.The most important means to prevent this disease is to optimize the lifestyle.Our study aimed to follow-up the effect of moderate caloric restriction and increase of physical activityon clinical and metabolic parameters in persons at risk to develop type 2 diabetes.Twenty-three overweight or obese patients with either altered fasting glucose or altered glucosetolerance were included in this study. They were followed up for 2 years for clinical progress and metabolicprofile, while on lifestyle counseling.The dietary and physical recommendations to improve lifestyle were followed by a small reduction inthe BMI, total cholesterol, systolic and diastolic blood pressure, together with an increase of HDL at 1 and 2years of dietary counseling. However there was a significant reduction in abdominal circumference, fastingglycemia and glycemia at 2 hours during oral glucose tolerance test.The small reduction in BMI indicates the need of a more intensive lifestyle conseling.

  16. Use of optimized 1D TOCSY NMR for improved quantitation and metabolomic analysis of biofluids

    Energy Technology Data Exchange (ETDEWEB)

    Sandusky, Peter [Eckerd College, Department of Chemistry (United States); Appiah-Amponsah, Emmanuel; Raftery, Daniel, E-mail: raftery@purdue.edu [Purdue University, Department of Chemistry (United States)

    2011-04-15

    One dimensional selective TOCSY experiments have been shown to be advantageous in providing improved data inputs for principle component analysis (PCA) (Sandusky and Raftery 2005a, b). Better subpopulation cluster resolution in the observed scores plots results from the ability to isolate metabolite signals of interest via the TOCSY based filtering approach. This report reexamines the quantitative aspects of this approach, first by optimizing the 1D TOCSY experiment as it relates to the measurement of biofluid constituent concentrations, and second by comparing the integration of 1D TOCSY read peaks to the bucket integration of 1D proton NMR spectra in terms of precision and accuracy. This comparison indicates that, because of the extensive peak overlap that occurs in the 1D proton NMR spectra of biofluid samples, bucket integrals are often far less accurate as measures of individual constituent concentrations than 1D TOCSY read peaks. Even spectral fitting approaches have proven difficult in the analysis of significantly overlapped spectral regions. Measurements of endogenous taurine made over a sample population of human urine demonstrates that, due to background signals from other constituents, bucket integrals of 1D proton spectra routinely overestimate the taurine concentrations and distort its variation over the sample population. As a result, PCA calculations performed using data matrices incorporating 1D TOCSY determined taurine concentrations produce better scores plot subpopulation cluster resolution.

  17. Improved detection of multiple environmental antibiotics through an optimized sample extraction strategy in liquid chromatography-mass spectrometry analysis.

    Science.gov (United States)

    Yi, Xinzhu; Bayen, Stéphane; Kelly, Barry C; Li, Xu; Zhou, Zhi

    2015-12-01

    A solid-phase extraction/liquid chromatography/electrospray ionization/multi-stage mass spectrometry (SPE-LC-ESI-MS/MS) method was optimized in this study for sensitive and simultaneous detection of multiple antibiotics in urban surface waters and soils. Among the seven classes of tested antibiotics, extraction efficiencies of macrolides, lincosamide, chloramphenicol, and polyether antibiotics were significantly improved under optimized sample extraction pH. Instead of only using acidic extraction in many existing studies, the results indicated that antibiotics with low pK a values (antibiotics with high pK a values (>7) were extracted more efficiently under neutral conditions. The effects of pH were more obvious on polar compounds than those on non-polar compounds. Optimization of extraction pH resulted in significantly improved sample recovery and better detection limits. Compared with reported values in the literature, the average reduction of minimal detection limits obtained in this study was 87.6% in surface waters (0.06-2.28 ng/L) and 67.1% in soils (0.01-18.16 ng/g dry wt). This method was subsequently applied to detect antibiotics in environmental samples in a heavily populated urban city, and macrolides, sulfonamides, and lincomycin were frequently detected. Antibiotics with highest detected concentrations were sulfamethazine (82.5 ng/L) in surface waters and erythromycin (6.6 ng/g dry wt) in soils. The optimized sample extraction strategy can be used to improve the detection of a variety of antibiotics in environmental surface waters and soils.

  18. Analysis and Improvement of TCP Congestion Control Mechanism Based on Global Optimization Model

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Network flow control is formulated as a global optimization problem of user profit. A general global optimization flow control model is established. This model combined with the stochastic model of TCP is used to study the global rate allocation characteristic of TCP. Analysis shows when active queue manage ment is used in network TCP rates tend to be allocated to maximize the aggregate of a user utility function Us (called Us fairness). The TCP throughput formula is derived. An improved TCP congestion control mecha nism is proposed. Simulations show its throughput is TCP friendly when competing with existing TCP and its rate change is smoother. Therefore, it is suitable to carry multimedia applications.

  19. Whether noninvasive optimization of AV and VV delays improves the response to cardiac resynchronization therapy.

    Science.gov (United States)

    Urbanek, Bożena; Chudzik, Michał; Klimczak, Artur; Rosiak, Marcin; Lewek, Joanna; Wranicz, Jerzy Krzysztof

    2013-01-01

    Device optimization is not routinely performed in patients who underwent cardiac resynchronization therapy (CRT) device implantation. Noninvasive optimization of CRT devices by measurement of cardiac output (CO) can be used as a simple method to assess ventricular systolic performance. The aim of this study was to assess whether optimization of atrioventricular (AV) and interventricular (VV) delay can improve hemodynamic response to CRT and whether this optimization should be performed for each patient individually. Twenty patients with advanced heart failure New York Heart Association (NYHA) class III/IV, left ventricular ejection fraction ≤ 35% and left bundle branch block (QRS ≥ 120 ms) in sinus rhythm were evaluated from 24 h to 48 h after implantation of a CRT device by means of impedance cardiography (ICG). CO was first measured at each patient's intrinsic rhythm. Patients then underwent adjustments of AV and VV delay from 80 ms to 140 ms and from -60 ms to +60 ms, respectively in 20 ms increment steps and CO at each setting was measured by ICG. Both AV and VV delays were programmed according to the greatest improvement in CO compared to intrinsic rhythm. There was a statistically signifi cant increase in CO measured at the intrinsic rhythm compared to different AV delay by mean of 21% (3.8 ± 1.0 vs. 4.6 ± 0.1 L/min, p AV/VV delays with left ventricle-preexcitation or simultaneous biventricular pacing caused additional increased CO from intrinsic rhythm by mean of 32.6% (3.8 ± 1.0 vs. 5.04 ± ± 1.0 L/min, p AV/VV setting delays also resulted in improved hemodynamic responses compared to VV factory setting delay. Both AV and VV delay optimization should be performed in clinical practice. Optimal AV delay improved outcome. However, combination of optimized AV/VV delays provided the best hemodynamic response. Optimized AV/VV delays with left ventricle-preexcitation or simultaneous biventricular pacing increased hemodynamic output compared to intrinsic

  20. Improved Fractal Space Filling Curves Hybrid Optimization Algorithm for Vehicle Routing Problem.

    Science.gov (United States)

    Yue, Yi-xiang; Zhang, Tong; Yue, Qun-xing

    2015-01-01

    Vehicle Routing Problem (VRP) is one of the key issues in optimization of modern logistics system. In this paper, a modified VRP model with hard time window is established and a Hybrid Optimization Algorithm (HOA) based on Fractal Space Filling Curves (SFC) method and Genetic Algorithm (GA) is introduced. By incorporating the proposed algorithm, SFC method can find an initial and feasible solution very fast; GA is used to improve the initial solution. Thereafter, experimental software was developed and a large number of experimental computations from Solomon's benchmark have been studied. The experimental results demonstrate the feasibility and effectiveness of the HOA.

  1. Small Signal Stability Improvement of Power Systems Using Optimal Load Responses in Competitive Electricity Markets

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Chen, Zhe;

    2011-01-01

    Since the hourly spot market price is available one day ahead in Denmark, the price could be transferred to the consumers and they may shift some of their loads from high price periods to the low price periods in order to save their energy costs. The optimal load response to an electricity price...... price is proposed. A 17-bus power system with high wind power penetrations, which resembles the Eastern Danish power system, is chosen as the study case. Simulation results show that the optimal load response to electricity prices is an effective measure to improve the small signal stability of power...

  2. A comparison of optimization software for mesh shape-quality improvement problems.

    Energy Technology Data Exchange (ETDEWEB)

    Freitag, L.; Knupp, P.; Munson, T.; Shontz, S.

    2002-08-19

    Simplicial mesh shape-quality can be improved by optimizing an objective function based on tetrahedral shape measures. If the objective function is formulated in terms of all elements in a given mesh rather than a local patch, one is confronted with a large-scale, nonlinear, constrained numerical optimization problem. We investigate the use of six general-purpose state-of-the-art solvers and two custom-developed methods to solve the resulting large-scale problem. The performance of each method is evaluated in terms of robustness, time to solution, convergence properties, and scalability on several two- and three-dimensional test cases.

  3. Improved Optimization for the Cluster Jastrow Antisymmetric Geminal Power and Tests on Triple-Bond Dissociations

    CERN Document Server

    Neuscamman, Eric

    2016-01-01

    We present a novel specialization of the variational Monte Carlo linear method for the optimization of the recently introduced cluster Jastrow antisymmetric geminal power ansatz, achieving a lower-order polynomial cost scaling than would be possible with a naive application of the linear method and greatly improving optimization performance relative to the previously employed quasi-Newton approach. We test the methodology on highly multi-reference triple-bond stretches, achieving accuracies superior to traditional coupled cluster theory and multi-reference perturbation theory in both the typical example of N$_2$ and the transition-metal-oxide example of [ScO]$^+$.

  4. Improved Fractal Space Filling Curves Hybrid Optimization Algorithm for Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Yi-xiang Yue

    2015-01-01

    Full Text Available Vehicle Routing Problem (VRP is one of the key issues in optimization of modern logistics system. In this paper, a modified VRP model with hard time window is established and a Hybrid Optimization Algorithm (HOA based on Fractal Space Filling Curves (SFC method and Genetic Algorithm (GA is introduced. By incorporating the proposed algorithm, SFC method can find an initial and feasible solution very fast; GA is used to improve the initial solution. Thereafter, experimental software was developed and a large number of experimental computations from Solomon’s benchmark have been studied. The experimental results demonstrate the feasibility and effectiveness of the HOA.

  5. Improved Fractal Space Filling Curves Hybrid Optimization Algorithm for Vehicle Routing Problem

    Science.gov (United States)

    Yue, Yi-xiang; Zhang, Tong; Yue, Qun-xing

    2015-01-01

    Vehicle Routing Problem (VRP) is one of the key issues in optimization of modern logistics system. In this paper, a modified VRP model with hard time window is established and a Hybrid Optimization Algorithm (HOA) based on Fractal Space Filling Curves (SFC) method and Genetic Algorithm (GA) is introduced. By incorporating the proposed algorithm, SFC method can find an initial and feasible solution very fast; GA is used to improve the initial solution. Thereafter, experimental software was developed and a large number of experimental computations from Solomon's benchmark have been studied. The experimental results demonstrate the feasibility and effectiveness of the HOA. PMID:26167171

  6. Tuning Monotonic Basin Hopping: Improving the Efficiency of Stochastic Search as Applied to Low-Thrust Trajectory Optimization

    Science.gov (United States)

    Englander, Jacob A.; Englander, Arnold C.

    2014-01-01

    Trajectory optimization methods using monotonic basin hopping (MBH) have become well developed during the past decade [1, 2, 3, 4, 5, 6]. An essential component of MBH is a controlled random search through the multi-dimensional space of possible solutions. Historically, the randomness has been generated by drawing random variable (RV)s from a uniform probability distribution. Here, we investigate the generating the randomness by drawing the RVs from Cauchy and Pareto distributions, chosen because of their characteristic long tails. We demonstrate that using Cauchy distributions (as first suggested by J. Englander [3, 6]) significantly improves monotonic basin hopping (MBH) performance, and that Pareto distributions provide even greater improvements. Improved performance is defined in terms of efficiency and robustness. Efficiency is finding better solutions in less time. Robustness is efficiency that is undiminished by (a) the boundary conditions and internal constraints of the optimization problem being solved, and (b) by variations in the parameters of the probability distribution. Robustness is important for achieving performance improvements that are not problem specific. In this work we show that the performance improvements are the result of how these long-tailed distributions enable MBH to search the solution space faster and more thoroughly. In developing this explanation, we use the concepts of sub-diffusive, normally-diffusive, and super-diffusive random walks (RWs) originally developed in the field of statistical physics.

  7. Optimization of oestradiol assays to improve utility in an in vitro fertilization setting.

    Science.gov (United States)

    Peavey, M; Akbas, N; Gibbons, W; Zarutskie, P; Devaraj, S

    2017-01-01

    Background The measurement of oestradiol is an integral component for the management of ovarian stimulation for in vitro fertilization. Automated immunoassays offer fast assay times and high throughput, with less sensitivity and specificity. The aim of this study is to optimize the oestradiol assay in patients undergoing ovarian stimulation for in vitro fertilization via comparison of oestradiol values obtained using two immunoassays compared with mass spectrometry. Methods Patients undergoing ovarian stimulation were prospectively recruited. Serum samples were analysed with ADVIA Centaur® CP Immunoassay, Abbott Architect i1000® immunoassay and AB Sciex 5500 liquid chromatography-tandem mass spectrometry (LC-MS/MS) systems. Per cent bias was determined for each system to report the average tendency of the values to be larger or smaller than the LC-MS/MS value. Linear regression of total follicular volume and oestradiol was computed. Results The ADVIA Centaur® CP assay had a positive bias of 20% compared with LC-MS/MS, while the Architect i1000® had a non-significant, negative bias of 0.3%. With regression fit, a clear, positive relationship was seen between follicular volume and oestradiol. The Architect i1000® assay had a greater correlation (R(2 )= 0.46) compared with Centaur® CP (R(2 )= 0.36), when oestradiol values were >1000 pg/mL (3670 pmol/L). Conclusions The Abbott Architect i1000® oestradiol assay exhibits greater agreement with LC-MS/MS and exhibited better correlation to follicular volume when oestradiol values are >1000 pg/mL (3670 pmol/L), prompting a change in the clinic's oestradiol platform. Attention to assay quality assurance via LC-MS/MS can improve the oestradiol accuracy and permit more informed clinical decisions for improved patient outcomes.

  8. State Feedback H∞ Control of Power Units Based on an Improved Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Zhongqiang Wu

    2015-01-01

    Full Text Available A new state feedback H∞ control scheme is presented used in the boiler-turbine power units based on an improved particle swarm optimizing algorithm. Firstly, the nonlinear system is transformed into a linear time-varying system; then the H∞ control problem is transformed into the solution of a Riccati equation. The control effect of H∞ controller depends on the selection of matrix P, so an improved particle swarm optimizing (PSO algorithm by introducing differential evolution algorithm is used to solve the Riccati equation. The main purpose is that mutation and crossover are introduced for a new population, and the population diversity is improved. It is beneficial to eliminate stagnation caused by premature convergence, and the algorithm convergence rate is improved. Finally, the real-time optimizing of the controller parameters is realized. Theoretical analysis and simulation results show that a state feedback H∞ controller can be obtained, which can ensure asymptotic stability of the system, and the double objectives of stabilizing system and suppressing the disturbance are got. The system can work well over a large range working point.

  9. Improved electrical properties of zinc-tin oxide TFTs by inkjet process optimization

    Science.gov (United States)

    Lee, Seung-Hyun; Choi, Woon-Seop

    2014-07-01

    Inkjet printing process was optimized to improve the electrical properties of inkjet-printed zinc-tin oxide thin-film transistors. Among the process conditions evaluated, inkjet voltage and substrate temperature were found to be the key factors for obtaining uniform thin-films and good thin-film transistors. The optimization process with a jetting voltage of 60 V and substrate temperature of 50°C gave good electrical properties, such as a field-effect mobility of 5.11 cm2/V s, a threshold voltage of 2.83 V, a subthreshold slope of 1.33 V/dec, and an on-to-off current ratio of 108. The electrical properties of the inkjet-optimized TFTs were superior to those of the unoptimized inkjet TFTs. A positive bias stability was also investigated.

  10. A Parameter Estimation Method for Nonlinear Systems Based on Improved Boundary Chicken Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Shaolong Chen

    2016-01-01

    Full Text Available Parameter estimation is an important problem in nonlinear system modeling and control. Through constructing an appropriate fitness function, parameter estimation of system could be converted to a multidimensional parameter optimization problem. As a novel swarm intelligence algorithm, chicken swarm optimization (CSO has attracted much attention owing to its good global convergence and robustness. In this paper, a method based on improved boundary chicken swarm optimization (IBCSO is proposed for parameter estimation of nonlinear systems, demonstrated and tested by Lorenz system and a coupling motor system. Furthermore, we have analyzed the influence of time series on the estimation accuracy. Computer simulation results show it is feasible and with desirable performance for parameter estimation of nonlinear systems.

  11. On the use of topology optimization for improving heat transfer in molding process

    Science.gov (United States)

    Agazzi, A.; LeGoff, R.; Truc-Vu, C.

    2016-10-01

    In the plastic industry, one of the key factor is to control heat transfer. One way to achieve that goal is to design an effective cooling system. But in some area of the mold, where it is not possible to design cooling system, the use of a highly conductive material, such as copper pin, is often used. Most of the time, the location, the size and the quantity of the copper pin are made by empirical considerations, without using optimization procedures. In this article, it is proposed to use topology optimization, in order to improve transient conductive heat transfer in an injection/blowing mold. Two methodologies are applied and compared. Finally, the optimal distribution of cooper pin in the mold is given.

  12. Optimal Placement of Static Compensators for Global Voltage Sag Mitigation and Power System Performance Improvement

    Directory of Open Access Journals (Sweden)

    M.A. Ali

    2015-06-01

    Full Text Available This study presents a new multi-objective approach for optimal placement of Static Compensator (STATCOM for global (overall voltage sag mitigation as well as for power system performance improvement. The problem is formulated as a non linear constrained multi-objective optimization problem and solved using Genetic Algorithm (GA. The proposed method determines optimal locations of STATCOMs which simultaneously minimizes the overall voltage sags at network buses, bus voltage deviation and system real power loss and maximizes the voltage stability margin of the system. The proposed approach has been applied on IEEE 24-bus Reliability Test System (RTS and IEEE 57-bus test systems. The details of implementation and simulation results are presented. The application results are promising and encouraging.

  13. Optimization of Camera Arrangement Using Correspondence Field to Improve Depth Estimation.

    Science.gov (United States)

    Fu, Shichao; Safaei, Farzad; Li, Wanqing

    2017-04-18

    Stereo matching algorithms attempt to estimate depth from the images obtained by two cameras. In most cases, the arrangement of cameras (their locations and orientations with respect to the scene) are determined based on human experience. In this paper, it is shown that the camera arrangement can be optimized using the concept of correspondence field (CF) for better acquisition of depth. Specifically, the paper demonstrates the relationship between the correspondence field of a pair of cameras and depth estimation accuracy and presents a method to optimize their arrangement based on the gradient of CF. The experimental results show that a pair of cameras optimized by the proposed method can improve the accuracy of depth estimation by as much as 30% compared to the conventional camera arrangements.

  14. Improved Relative-Entropy Method for Eccentricity Filtering in Roundness Measurement Based on Information Optimization

    Directory of Open Access Journals (Sweden)

    Xintao Xia

    2013-05-01

    Full Text Available In this study, we propose the improved relative-entropy of the ideal circle function to the measured information of the radius error of the workpiece surface to make an eccentricity filtering in roundness measurement. Along with a correct assessment for the parameters of the eccentricity filtering, the extracted information from the measured information is obtained by the minimization of the improved relative-entropy. The case studies show that the information optimization is characterized by decreasing the improved relative-entropy, the extracted information almost coincides with the real information, the improved relative-entropy has a strong immunity to the stochastic disturbance of the rough work piece-surface and the increase of the minimum of the improved relative-entropy counteracts the effect of the stochastic disturbance on the assessment for parameters in eccentricity filtering.

  15. An Improved Multiobjective Particle Swarm Optimization Algorithm Using Minimum Distance of Point to Line

    Directory of Open Access Journals (Sweden)

    Zhengwu Fan

    2017-01-01

    Full Text Available In a multiobjective particle swarm optimization algorithm, selection of the global best particle for each particle of the population from a set of Pareto optimal solutions has a significant impact on the convergence and diversity of solutions, especially when optimizing problems with a large number of objectives. In this paper, a new method is introduced for selecting the global best particle, which is minimum distance of point to line multiobjective particle swarm optimization (MDPL-MOPSO. Using the basic concept of minimum distance of point to line and objective, the global best particle among archive members can be selected. Different test functions were used to test and compare MDPL-MOPSO with CD-MOPSO. The result shows that the convergence and diversity of MDPL-MOPSO are relatively better than CD-MOPSO. Finally, the proposed multiobjective particle swarm optimization algorithm is used for the Pareto optimal design of a five-degree-of-freedom vehicle vibration model, which resulted in numerous effective trade-offs among conflicting objectives, including seat acceleration, front tire velocity, rear tire velocity, relative displacement between sprung mass and front tire, and relative displacement between sprung mass and rear tire. The superiority of this work is demonstrated by comparing the obtained results with the literature.

  16. Optimal setting of FACTS devices for voltage stability improvement using PSO adaptive GSA hybrid algorithm

    Directory of Open Access Journals (Sweden)

    Sai Ram Inkollu

    2016-09-01

    Full Text Available This paper presents a novel technique for optimizing the FACTS devices, so as to maintain the voltage stability in the power transmission systems. Here, the particle swarm optimization algorithm (PSO and the adaptive gravitational search algorithm (GSA technique are proposed for improving the voltage stability of the power transmission systems. In the proposed approach, the PSO algorithm is used for optimizing the gravitational constant and to improve the searching performance of the GSA. Using the proposed technique, the optimal settings of the FACTS devices are determined. The proposed algorithm is an effective method for finding out the optimal location and the sizing of the FACTS controllers. The optimal locations and the power ratings of the FACTS devices are determined based on the voltage collapse rating as well as the power loss of the system. Here, two FACTS devices are used to evaluate the performance of the proposed algorithm, namely, the unified power flow controller (UPFC and the interline power flow controller (IPFC. The Newton–Raphson load flow study is used for analyzing the power flow in the transmission system. From the power flow analysis, bus voltages, active power, reactive power, and power loss of the transmission systems are determined. Then, the voltage stability is enhanced while satisfying a given set of operating and physical constraints. The proposed technique is implemented in the MATLAB platform and consequently, its performance is evaluated and compared with the existing GA based GSA hybrid technique. The performance of the proposed technique is tested with the benchmark system of IEEE 30 bus using two FACTS devices such as, the UPFC and the IPFC.

  17. Multi-point optimization on meridional shape of a centrifugal pump impeller for performance improvement

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Ji; Wang, Wen Jie; Yuan, Shouqi [National Research Center of Pumps, Jiangsu University, Zhenjiang (China)

    2016-11-15

    A wide operating band is important for a pump to safely perform at maximum efficiency while saving energy. To widen the operating range, a multi-point optimization process based on numerical simulations in order to improve impeller performance of a centrifugal pump used in nuclear plant applications is proposed by this research. The Reynolds average Navier Stokes equations are utilized to perform the calculations. The meridional shape of the impeller was optimized based on the following four parameters; shroud arc radius, hub arc radius, shroud angle, and hub angle as the design variables. Efficiencies calculated under 0.6Qd, 1.0Qd and 1.62Qd were selected as the three optimized objectives. The Design of experiment method was applied to generate various impellers while 35 impellers were generated by the Latin hypercube sampling method. A Response surface function based on a second order function was applied to construct a mathematical relationship between the objectives and design variables. A multi-objective genetic algorithm was utilized to solve the response surface function to obtain the best optimized objectives as well as the best combination of design parameters. The results indicated that the pump performance predicted by numerical simulation was in agreement with the experimental performance. The optimized efficiencies based on the three operating conditions were increased by 3.9 %, 6.1 % and 2.6 %, respectively. In addition, the velocity distribution, pressure distribution, streamline and turbulence kinetic energy distribution of the optimized and reference impeller were compared and analyzed to illustrate the performance improvement.

  18. Natalizumab Significantly Improves Cognitive Impairment over Three Years in MS: Pattern of Disability Progression and Preliminary MRI Findings.

    Directory of Open Access Journals (Sweden)

    Flavia Mattioli

    Full Text Available Previous studies reported that Multiple Sclerosis (MS patients treated with natalizumab for one or two years exhibit a significant reduction in relapse rate and in cognitive impairment, but the long term effects on cognitive performance are unknown. This study aimed to evaluate the effects of natalizumab on cognitive impairment in a cohort of 24 consecutive patients with relapsing remitting MS treated for 3 years. The neuropsychological tests, as well as relapse number and EDSS, were assessed at baseline and yearly for three years. The impact on cortical atrophy was also considered in a subgroup of them, and are thus to be considered as preliminary. Results showed a significant reduction in the number of impaired neuropsychological tests after three years, a significant decrease in annualized relapse rate at each time points compared to baseline and a stable EDSS. In the neuropsychological assessment, a significant improvement in memory, attention and executive function test scores was detected. Preliminary MRI data show that, while GM volume did not change at 3 years, a significantly greater parahippocampal and prefrontal gray matter density was noticed, the former correlating with neuropsychological improvement in a memory test. This study showed that therapy with Natalizumab is helpful in improving cognitive performance, and is likely to have a protective role on grey matter, over a three years follow-up.

  19. How to Improve Academic Optimism? an Inquiry from the Perspective of School Resource and Investment

    Science.gov (United States)

    Wu, Jason Hsinchieh; Sheu, Tian-Ming

    2015-01-01

    Previous studies have identified many school variables which can have significant effect on academic optimism. However, most of these identified variables are leadership or psychological constructs; thus, it is often too abstract for school administrators to translate into real practice. Therefore, this study adopted the perspective of school…

  20. How to Improve Academic Optimism? an Inquiry from the Perspective of School Resource and Investment

    Science.gov (United States)

    Wu, Jason Hsinchieh; Sheu, Tian-Ming

    2015-01-01

    Previous studies have identified many school variables which can have significant effect on academic optimism. However, most of these identified variables are leadership or psychological constructs; thus, it is often too abstract for school administrators to translate into real practice. Therefore, this study adopted the perspective of school…

  1. Adaptive Wavelet Threshold Denoising Method for Machinery Sound Based on Improved Fruit Fly Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Jing Xu

    2016-07-01

    Full Text Available As the sound signal of a machine contains abundant information and is easy to measure, acoustic-based monitoring or diagnosis systems exhibit obvious superiority, especially in some extreme conditions. However, the sound directly collected from industrial field is always polluted. In order to eliminate noise components from machinery sound, a wavelet threshold denoising method optimized by an improved fruit fly optimization algorithm (WTD-IFOA is proposed in this paper. The sound is firstly decomposed by wavelet transform (WT to obtain coefficients of each level. As the wavelet threshold functions proposed by Donoho were discontinuous, many modified functions with continuous first and second order derivative were presented to realize adaptively denoising. However, the function-based denoising process is time-consuming and it is difficult to find optimal thresholds. To overcome these problems, fruit fly optimization algorithm (FOA was introduced to the process. Moreover, to avoid falling into local extremes, an improved fly distance range obeying normal distribution was proposed on the basis of original FOA. Then, sound signal of a motor was recorded in a soundproof laboratory, and Gauss white noise was added into the signal. The simulation results illustrated the effectiveness and superiority of the proposed approach by a comprehensive comparison among five typical methods. Finally, an industrial application on a shearer in coal mining working face was performed to demonstrate the practical effect.

  2. Improving Kinematic Accuracy of Soft Wearable Data Gloves by Optimizing Sensor Locations.

    Science.gov (United States)

    Kim, Dong Hyun; Lee, Sang Wook; Park, Hyung-Soon

    2016-05-26

    Bending sensors enable compact, wearable designs when used for measuring hand configurations in data gloves. While existing data gloves can accurately measure angular displacement of the finger and distal thumb joints, accurate measurement of thumb carpometacarpal (CMC) joint movements remains challenging due to crosstalk between the multi-sensor outputs required to measure the degrees of freedom (DOF). To properly measure CMC-joint configurations, sensor locations that minimize sensor crosstalk must be identified. This paper presents a novel approach to identifying optimal sensor locations. Three-dimensional hand surface data from ten subjects was collected in multiple thumb postures with varied CMC-joint flexion and abduction angles. For each posture, scanned CMC-joint contours were used to estimate CMC-joint flexion and abduction angles by varying the positions and orientations of two bending sensors. Optimal sensor locations were estimated by the least squares method, which minimized the difference between the true CMC-joint angles and the joint angle estimates. Finally, the resultant optimal sensor locations were experimentally validated. Placing sensors at the optimal locations, CMC-joint angle measurement accuracies improved (flexion, 2.8° ± 1.9°; abduction, 1.9° ± 1.2°). The proposed method for improving the accuracy of the sensing system can be extended to other types of soft wearable measurement devices.

  3. Improving Kinematic Accuracy of Soft Wearable Data Gloves by Optimizing Sensor Locations

    Directory of Open Access Journals (Sweden)

    Dong Hyun Kim

    2016-05-01

    Full Text Available Bending sensors enable compact, wearable designs when used for measuring hand configurations in data gloves. While existing data gloves can accurately measure angular displacement of the finger and distal thumb joints, accurate measurement of thumb carpometacarpal (CMC joint movements remains challenging due to crosstalk between the multi-sensor outputs required to measure the degrees of freedom (DOF. To properly measure CMC-joint configurations, sensor locations that minimize sensor crosstalk must be identified. This paper presents a novel approach to identifying optimal sensor locations. Three-dimensional hand surface data from ten subjects was collected in multiple thumb postures with varied CMC-joint flexion and abduction angles. For each posture, scanned CMC-joint contours were used to estimate CMC-joint flexion and abduction angles by varying the positions and orientations of two bending sensors. Optimal sensor locations were estimated by the least squares method, which minimized the difference between the true CMC-joint angles and the joint angle estimates. Finally, the resultant optimal sensor locations were experimentally validated. Placing sensors at the optimal locations, CMC-joint angle measurement accuracies improved (flexion, 2.8° ± 1.9°; abduction, 1.9° ± 1.2°. The proposed method for improving the accuracy of the sensing system can be extended to other types of soft wearable measurement devices.

  4. An Improved Genetic Algorithm for Optimal Stationary Energy Storage System Locating and Sizing

    Directory of Open Access Journals (Sweden)

    Bin Wang

    2014-10-01

    Full Text Available The application of a stationary ultra-capacitor energy storage system (ESS in urban rail transit allows for the recuperation of vehicle braking energy for increasing energy savings as well as for a better vehicle voltage profile. This paper aims to obtain the best energy savings and voltage profile by optimizing the location and size of ultra-capacitors. This paper firstly raises the optimization objective functions from the perspectives of energy savings, regenerative braking cancellation and installation cost, respectively. Then, proper mathematical models of the DC (direct current traction power supply system are established to simulate the electrical load-flow of the traction supply network, and the optimization objections are evaluated in the example of a Chinese metro line. Ultimately, a methodology for optimal ultra-capacitor energy storage system locating and sizing is put forward based on the improved genetic algorithm. The optimized result shows that certain preferable and compromised schemes of ESSs’ location and size can be obtained, acting as a compromise between satisfying better energy savings, voltage profile and lower installation cost.

  5. Improved nonlinear optimization in the storage ring of the modern synchrotron radiation light source

    Institute of Scientific and Technical Information of China (English)

    TIAN Shun-Qiang; LIU Gui-Min; HOU Jie; CHEN Guang-Ling; CHEN Sen-Yu

    2009-01-01

    In the storage ring of the third generation light sources,nonlinear optimization is an indispensable course in order to obtain ample dynamic acceptances and to reach high injection efficiency and long beam lifetime,especially in a low emittance lattice.An improved optimization algorithm based on the single resonance approach,which takes relative weight and initial Harmonic Sextupole Integral Strength (HSIS) as search variables,is discussed in this paper.Applications of the improved method in several test lattices are presented.Detailed analysis of the storage ring of the Shanghai Synchrotron Radiation Facility (SSRF) is particularly emphasized.Furthermore,cancellation of the driving terms is investigated to reveal the physical mechanism of the harmonic sextupole compensation.Sensitivity to the weight and the initial HSIS as well as dependence of the optimum solution on the convergent factor is analyzed.

  6. Fault Diagnosis of Power System Based on Improved Genetic Optimized BP-NN

    Directory of Open Access Journals (Sweden)

    Yuan Pu

    2015-01-01

    Full Text Available BP neural network (Back-Propagation Neural Network, BP-NN is one of the most widely neural network models and is applied to fault diagnosis of power system currently. BP neural network has good self-learning and adaptive ability and generalization ability, but the operation process is easy to fall into local minima. Genetic algorithm has global optimization features, and crossover is the most important operation of the Genetic Algorithm. In this paper, we can modify the crossover of traditional Genetic Algorithm, using improved genetic algorithm optimized BP neural network training initial weights and thresholds, to avoid the problem of BP neural network fall into local minima. The results of analysis by an example, the method can efficiently diagnose network fault location, and improve fault-tolerance and grid fault diagnosis effect.

  7. An Improved Cuckoo Search Optimization Algorithm for the Problem of Chaotic Systems Parameter Estimation

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2016-01-01

    Full Text Available This paper proposes an improved cuckoo search (ICS algorithm to establish the parameters of chaotic systems. In order to improve the optimization capability of the basic cuckoo search (CS algorithm, the orthogonal design and simulated annealing operation are incorporated in the CS algorithm to enhance the exploitation search ability. Then the proposed algorithm is used to establish parameters of the Lorenz chaotic system and Chen chaotic system under the noiseless and noise condition, respectively. The numerical results demonstrate that the algorithm can estimate parameters with high accuracy and reliability. Finally, the results are compared with the CS algorithm, genetic algorithm, and particle swarm optimization algorithm, and the compared results demonstrate the method is energy-efficient and superior.

  8. An Improved Cuckoo Search Optimization Algorithm for the Problem of Chaotic Systems Parameter Estimation.

    Science.gov (United States)

    Wang, Jun; Zhou, Bihua; Zhou, Shudao

    2016-01-01

    This paper proposes an improved cuckoo search (ICS) algorithm to establish the parameters of chaotic systems. In order to improve the optimization capability of the basic cuckoo search (CS) algorithm, the orthogonal design and simulated annealing operation are incorporated in the CS algorithm to enhance the exploitation search ability. Then the proposed algorithm is used to establish parameters of the Lorenz chaotic system and Chen chaotic system under the noiseless and noise condition, respectively. The numerical results demonstrate that the algorithm can estimate parameters with high accuracy and reliability. Finally, the results are compared with the CS algorithm, genetic algorithm, and particle swarm optimization algorithm, and the compared results demonstrate the method is energy-efficient and superior.

  9. Improving performance of flat-plate photobioreactors by installation of novel internal mixers optimized with computational fluid dynamics.

    Science.gov (United States)

    Huang, Jianke; Feng, Fei; Wan, Minxi; Ying, Jiangguo; Li, Yuanguang; Qu, Xiaoxing; Pan, Ronghua; Shen, Guomin; Li, Wei

    2015-04-01

    A novel mixer was developed to improve the performance of flat-plate photobioreactors (PBRs). The effects of mixer were theoretically evaluated using computational fluid dynamics (CFD) according to radial velocity of fluid and light/dark cycles within reactors. The structure parameters, including the riser width, top clearance, clearance between the baffles and walls, and number of the chambers were further optimized. The microalgae culture test aiming at validating the simulated results was conducted indoor. The results showed the maximum biomass concentrations in the optimized and archetype reactors were 32.8% (0.89 g L(-1)) and 19.4% (0.80 g L(-1)) higher than that in the control reactor (0.67 g L(-1)). Therefore, the novel mixer can significantly increase the fluid velocity along the light attenuation and light/dark cycles, thus further increased the maximum biomass concentration. The PBRs with novel mixers are greatly applicable for high-efficiency cultivation of microalgae.

  10. Improvement of the energy resolution via an optimized digital signal processing in GERDA Phase I

    Science.gov (United States)

    Agostini, M.; Allardt, M.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Barros, N.; Baudis, L.; Bauer, C.; Becerici-Schmidt, N.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode, T.; Borowicz, D.; Brudanin, V.; Brugnera, R.; Budjáš, D.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; D'Andrea, V.; Demidova, E. V.; Vacri, A. di; Domula, A.; Doroshkevich, E.; Egorov, V.; Falkenstein, R.; Fedorova, O.; Freund, K.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Hegai, A.; Heisel, M.; Hemmer, S.; Heusser, G.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Janicskó Csáthy, J.; Jochum, J.; Junker, M.; Kazalov, V.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Klimenko, A.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, ********************M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Majorovits, B.; Maneschg, W.; Medinaceli, E.; Misiaszek, M.; Moseev, P.; Nemchenok, I.; Palioselitis, D.; Panas, K.; Pandola, L.; Pelczar, K.; Pullia, A.; Riboldi, S.; Rumyantseva, N.; Sada, C.; Salathe, M.; Schmitt, C.; Schneider, B.; Schönert, S.; Schreiner, J.; Schütz, A.-K.; Schulz, O.; Schwingenheuer, B.; Selivanenko, O.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Stepaniuk, M.; Ur, C. A.; Vanhoefer, L.; Vasenko, A. A.; Veresnikova, A.; von Sturm, K.; Wagner, V.; Walter, M.; Wegmann, A.; Wester, T.; Wilsenach, H.; Wojcik, M.; Yanovich, E.; Zavarise, P.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.

    2015-06-01

    An optimized digital shaping filter has been developed for the Gerda experiment which searches for neutrinoless double beta decay in Ge. The Gerda Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) corresponding to 10 % at the value for decay in Ge is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping filter.

  11. Optimization of cycloidal water turbine and the performance improvement by individual blade control

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, In Seong; Lee, Yun Han; Kim, Seung Jo [School of Mechanical and Aerospace Engineering, Seoul National University, San 56-1, Sillim-dong, Gwanak-gu, Seoul, 151-742 (Korea)

    2009-09-15

    This paper investigates an advanced vertical axis turbine to enhance power generation from water energy. The turbine, known as a cycloidal water turbine, is a straight-bladed type adopting a cycloidal blade system that actively controls the rotor blades for improved turbine efficiency, according to the operating conditions. These characteristics enable the turbine to self-start and produce high electric power at a low flow speed, or under complex flow conditions. A parametric study has been carried out by CFD analysis, with various characteristics including different number of blades, chord length variations, variety of tip speed ratios, various hydrofoil shapes, and changing pitch and phase angles. Optimal parameters have been determined, and the performance of the turbine has achieved approximately 70% better performance than that of a fixed pitch turbine. An experimental study has also been carried out which shows that the results correlate quite well with the theoretical predictions although the power output was reduced due to the drag forces of the mechanical devices. Another numerical optimization was carried out to improve the rotor performance by adopting an individual blade control method. Controllable pitch angles were employed to maximize the rotor performance at various operating conditions. The optimized result obtained using genetic algorithm and parallel computing, shows an improvement in performance of around 25% compared with the cycloidal motion. (author)

  12. Psinsar Improvement Using Amplitude Dispersion Index Optimization of Dual Polarimetry Data

    Science.gov (United States)

    Esmaeili, M.; Motagh, M.

    2015-12-01

    Persistent Scatterer Interferometry for SAR data (PSInSAR) improves the ability of conventional InSAR time-series methods by detecting and analysing pixels where the portion of spatiotemporal decorrelations on the phase is negligible. Using dual/quad polarized SAR data provide us with an additional source of information to improve further the capability of InSAR analysis. In this paper, we present a method to enhance PSInSAR using polarimetric optimization method on multi-temporal polarimetric SAR data. The optimization process has been implemented to minimize the Amplitude dispersion Index (ADI) of pixels in SAR images over the time based on the best scattering mechanism. We evaluated the method on a dataset including 17 dual polarization SAR data (HH/VV) acquired by TerraSAR-X data from July 2013 to January 2014 over Tehran plain, Iran. The area has been affected by high rate (> 20 cm/yr.) of surface subsidence due to groundwater overexploitation. The effectiveness of the method is compared for both agricultural and urban regions affected by land subsidence. Furthermore single pole and optimized polarization results are compared together and with external observations from GPS measurements. The results reveal that using optimum scattering mechanism decreases the ADI values in urban and non-urban regions and increase the PS Candidate pixels (PSC) about three times and subsequently improves the PS density about 50% more than using single channel datasets.

  13. Manufacturing Supply Chain Optimization Problem with Time Windows Based on Improved Orthogonal Genetic Algorithm

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xinhua

    2006-01-01

    Aim to the manufacturing supply chain optimization problem with time windows, presents an improved orthogonal genetic algorithm to solve it. At first, we decompose this problem into two sub-problems (distribution and routing) plus an interface mechanism to allow the two algorithms to collaborate in a master-slave fashion, with the distribution algorithm driving the routing algorithm. At second, we describe the proposed improved orthogonal genetic algorithm for solving giving problem detailedly. Finally, the examples suggest that this proposed approach is feasible, correct and valid.

  14. Overall Traveling-Wave-Tube Efficiency Improved By Optimized Multistage Depressed Collector Design

    Science.gov (United States)

    Vaden, Karl R.

    2002-01-01

    results show the improvement in collector efficiency from 89.7 to 93.8 percent, resulting in an increase of three overall efficiency points. In addition, the time to design a highly efficient MDC was reduced from a month to a few days. All work was done in-house at Glenn for the High Rate Data Delivery Program. Future plans include optimizing the MDC and TWT interaction circuit in tandem to further improve overall TWT efficiency.

  15. Improving the Thermostability and Optimal Temperature of a Lipase from the Hyperthermophilic Archaeon Pyrococcus furiosus by Covalent Immobilization

    Directory of Open Access Journals (Sweden)

    Roberta V. Branco

    2015-01-01

    Full Text Available A recombinant thermostable lipase (Pf2001Δ60 from the hyperthermophilic Archaeon Pyrococcus furiosus (PFUL was immobilized by hydrophobic interaction on octyl-agarose (octyl PFUL and by covalent bond on aldehyde activated-agarose in the presence of DTT at pH = 7.0 (one-point covalent attachment (glyoxyl-DTT PFUL and on glyoxyl-agarose at pH 10.2 (multipoint covalent attachment (glyoxyl PFUL. The enzyme’s properties, such as optimal temperature and pH, thermostability, and selectivity, were improved by covalent immobilization. The highest enzyme stability at 70°C for 48 h incubation was achieved for glyoxyl PFUL (around 82% of residual activity, whereas glyoxyl-DTT PFUL maintained around 69% activity, followed by octyl PFUL (27% remaining activity. Immobilization on glyoxyl-agarose improved the optimal temperature to 90°C, while the optimal temperature of octyl PFUL was 70°C. Also, very significant changes in activity with different substrates were found. In general, the covalent bond derivatives were more active than octyl PFUL. The E value also depended substantially on the derivative and the conditions used. It was observed that the reaction of glyoxyl-DTT PFUL using methyl mandelate as a substrate at pH 7 presented the best results for enantioselectivity E=22 and enantiomeric excess (ee (% = 91.

  16. Discussion of skill improvement in marine ecosystem dynamic models based on parameter optimization and skill assessment

    Science.gov (United States)

    Shen, Chengcheng; Shi, Honghua; Liu, Yongzhi; Li, Fen; Ding, Dewen

    2016-07-01

    Marine ecosystem dynamic models (MEDMs) are important tools for the simulation and prediction of marine ecosystems. This article summarizes the methods and strategies used for the improvement and assessment of MEDM skill, and it attempts to establish a technical framework to inspire further ideas concerning MEDM skill improvement. The skill of MEDMs can be improved by parameter optimization (PO), which is an important step in model calibration. An efficient approach to solve the problem of PO constrained by MEDMs is the global treatment of both sensitivity analysis and PO. Model validation is an essential step following PO, which validates the efficiency of model calibration by analyzing and estimating the goodness-of-fit of the optimized model. Additionally, by focusing on the degree of impact of various factors on model skill, model uncertainty analysis can supply model users with a quantitative assessment of model confidence. Research on MEDMs is ongoing; however, improvement in model skill still lacks global treatments and its assessment is not integrated. Thus, the predictive performance of MEDMs is not strong and model uncertainties lack quantitative descriptions, limiting their application. Therefore, a large number of case studies concerning model skill should be performed to promote the development of a scientific and normative technical framework for the improvement of MEDM skill.

  17. Significant improvement in photoluminescence of ZnSe(S) alloyed quantum dots prepared in high pH solution.

    Science.gov (United States)

    Zan, Feng; Ren, Jicun

    2010-01-01

    In this paper, we described a simple approach for aqueous synthesis of highly luminescent ZnSe(S) alloyed quantum dots (QDs) in the presence of 3-mercaptopropionic acid as stabilizers using zinc chloride and NaHSe as precursors. The synthesis conditions were systematically investigated. We observed that the pH value of the Zn precursor solution had significant influence on the optical properties and the structure of the as-prepared ZnSe(S) QDs. The optimal pH value and molar ratio of Zn(2+) to HSe(-) were 12.0 and 25 : 1 respectively. Under the optimal conditions, we prepared highly photoluminescent ZnSe(S) QDs at up to 31% quantum yield (compared with Rhodamine 6G). The characterization of HRTEM and XRD showed that the ZnSe(S) QDs had good monodispersity and nice crystal structure. The fluorescence life time spectra demonstrated that ZnSe(S) QDs had a long lifetime in contrast to fluorescent dyes. Compared with the currently used organometallic approach, our method was 'green', the reaction condition was mild and the as-prepared ZnSe(S) QDs were water-soluble. More importantly, our method was low cost, and was very suitable for large-scale synthesis of highly luminescent ZnSe(S) QDs for the future applications. Copyright © 2009 John Wiley & Sons, Ltd.

  18. Parametric Study and Optimization of Ceiling Fan Blades for Improved Aerodynamic Performance

    Directory of Open Access Journals (Sweden)

    Ehsan Adeeb

    2016-01-01

    Full Text Available This paper includes parametric study and optimization of non-linear ceiling fan blades by combining the techniques of Design of Experiments (DOE, Response Surface Methods (RSM and Computational Fluid Dynamics (CFD. Specifically, the nonlinear (elliptical planform shape of ceiling fan blade is investigated in conjunction with blade tip width, root and tip angle of attack. Sixteen cases are designed for three blade ceiling fan using two level full factorial model. The flow field is modeled using Reynolds-Averaged-Navier-Stokes approach. The performance variables used to formulate a multi-objective optimization problem are volumetric flow rate, torque and energy efficiency. Response Surface Method is used to generate the optimized design for non-linear ceiling fan blade profile. The results reveal that the interactions between the design variables play a significant role in determining the performance. It is concluded that the nonlinear forward sweep has a moderate effect on response parameters.

  19. Regulated expression of an isopentenyltransferase gene (IPT) in peanut significantly improves drought tolerance and increases yield under field conditions.

    Science.gov (United States)

    Qin, Hua; Gu, Qiang; Zhang, Junling; Sun, Li; Kuppu, Sundaram; Zhang, Yizheng; Burow, Mark; Payton, Paxton; Blumwald, Eduardo; Zhang, Hong

    2011-11-01

    Isopentenyltransferase (IPT) is a critical enzyme in the cytokinin biosynthetic pathway. The expression of IPT under the control of a maturation- and stress-induced promoter was shown to delay stress-induced plant senescence that resulted in an enhanced drought tolerance in both monocot and dicot plants. This report extends the earlier findings in tobacco and rice to peanut (Arachis hypogaea L.), an important oil crop and protein source. Regulated expression of IPT in peanut significantly improved drought tolerance in both laboratory and field conditions. Transgenic peanut plants maintained higher photosynthetic rates, higher stomatal conductance and higher transpiration than wild-type control plants under reduced irrigation conditions. More importantly, transgenic peanut plants produced significantly higher yields than wild-type control plants in the field, indicating a great potential for the development of crops with improved performance and yield in water-limited areas of the world.

  20. OPTIMIZING LISTENING SKILLS TO IMPROVE THE TOEFL SCORE OF STAIN PEKALONGAN STUDENTS

    Directory of Open Access Journals (Sweden)

    Riskiana .

    2015-10-01

    Full Text Available The fact that the students have problems in the three micro-skills of listening namely recognizing the English stress patterns, the reduced forms of words, and words boundaries and that the teachers never teach the students how to listen have made them get low TOEFL scores on listening section. This research aims at: (1 finding out whether optimizing listening skills can improve the students’ TOEFL scores on listening; and (2 describing the class situation during the teaching of toefl listening by optimizing listening skills. This action research is conducted in two cycles each of which is divided into planning, acting, observing, and reflecting. There are two kinds of data. The qualitative data taken from observation, interview, and questionnaire are analyzed by using Constant Comparative Method. The quantitative data taken from the pre-test in the pre-research, post-test in cycle 1, and post-test in cycle 2 are analyzed by using descriptive statistics. The subjects of the research are the STAIN Pekalongan students taking English 3 class, the TOEFL Preparation Class, in the Academic Year 2014/2015. The result of the research shows that: (1 teaching toefl listening section by optimizing listening skills is able to overcome the students’ problems in the three micro-skills of listening and consequently improve the students’ TOEFL scores on listening. Their average scores improve from 101 in the pre-test to 118 in the post-test of cycle 1 and 129 in the post-test of cycle 2; (2 The class situation is attractive and the students are actively involved in the various activities done during the teaching and learning process. In line with the success of optimizing listening skills in teaching TOEFL listening, it is suggested that teachers should examine their students’ listening problems so as to be able to teach them what they need in listening to English.

  1. Optimism

    Science.gov (United States)

    Carver, Charles S.; Scheier, Michael F.; Segerstrom, Suzanne C.

    2010-01-01

    Optimism is an individual difference variable that reflects the extent to which people hold generalized favorable expectancies for their future. Higher levels of optimism have been related prospectively to better subjective well-being in times of adversity or difficulty (i.e., controlling for previous well-being). Consistent with such findings, optimism has been linked to higher levels of engagement coping and lower levels of avoidance, or disengagement, coping. There is evidence that optimism is associated with taking proactive steps to protect one's health, whereas pessimism is associated with health-damaging behaviors. Consistent with such findings, optimism is also related to indicators of better physical health. The energetic, task-focused approach that optimists take to goals also relates to benefits in the socioeconomic world. Some evidence suggests that optimism relates to more persistence in educational efforts and to higher later income. Optimists also appear to fare better than pessimists in relationships. Although there are instances in which optimism fails to convey an advantage, and instances in which it may convey a disadvantage, those instances are relatively rare. In sum, the behavioral patterns of optimists appear to provide models of living for others to learn from. PMID:20170998

  2. Performance Improvement of a Return Channel in a Multistage Centrifugal Compressor Using Multiobjective Optimization.

    Science.gov (United States)

    Nishida, Yoshifumi; Kobayashi, Hiromi; Nishida, Hideo; Sugimura, Kazuyuki

    2013-05-01

    The effect of the design parameters of a return channel on the performance of a multistage centrifugal compressor was numerically investigated, and the shape of the return channel was optimized using a multiobjective optimization method based on a genetic algorithm to improve the performance of the centrifugal compressor. The results of sensitivity analysis using Latin hypercube sampling suggested that the inlet-to-outlet area ratio of the return vane affected the total pressure loss in the return channel, and that the inlet-to-outlet radius ratio of the return vane affected the outlet flow angle from the return vane. Moreover, this analysis suggested that the number of return vanes affected both the loss and the flow angle at the outlet. As a result of optimization, the number of return vane was increased from 14 to 22 and the area ratio was decreased from 0.71 to 0.66. The radius ratio was also decreased from 2.1 to 2.0. Performance tests on a centrifugal compressor with two return channels (the original design and optimized design) were carried out using two-stage test apparatus. The measured flow distribution exhibited a swirl flow in the center region and a reversed swirl flow near the hub and shroud sides. The exit flow of the optimized design was more uniform than that of the original design. For the optimized design, the overall two-stage efficiency and pressure coefficient were increased by 0.7% and 1.5%, respectively. Moreover, the second-stage efficiency and pressure coefficient were respectively increased by 1.0% and 3.2%. It is considered that the increase in the second-stage efficiency was caused by the increased uniformity of the flow, and the rise in the pressure coefficient was caused by a decrease in the residual swirl flow. It was thus concluded from the numerical and experimental results that the optimized return channel improved the performance of the multistage centrifugal compressor.

  3. Fractional Order PID Controller Design for Level Control of Three Tank System Based on Improved Cuckoo Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Meysam Gheisarnezhad

    2015-01-01

    Full Text Available Fractional-order PID (FOPID controller is a generalization of standard PID controller using fractional calculus. Compared with the Standard PID controller, two adjustable variables “differential order” and “integral order” are added to the PID controller.Three tank system is a nonlinear multivariable process that is a good prototype of chemical industrial processes. Cuckoo Optimization Algorithm (COA, that was recently introduced has shown its good performance in optimization problems. In this study, Improved Cuckoo Optimization Algorithm (ICOA has been presented. The aim of the paper is to compare different controllers tuned with a Improved Cuckoo Optimization Algorithm (ICOA for Three Tank System. In order to compare the performance of the optimized FOPID controller with other controllers, Genetic Algorithm(GA, Particle swarm optimization (PSO, Cuckoo Optimization Algorithm (COA and Imperialist Competitive Algorithm (ICA.

  4. Quality Assured Optimal Resource Provisioning and Scheduling Technique Based on Improved Hierarchical Agglomerative Clustering Algorithm (IHAC

    Directory of Open Access Journals (Sweden)

    A. Meenakshi

    2016-08-01

    Full Text Available Resource allocation is the task of convenient resources to different uses. In the context of an resources, entire economy, can be assigned by different means, such as markets or central planning. Cloud computing has become a new age technology that has got huge potentials in enterprises and markets. Clouds can make it possible to access applications and associated data from anywhere. The fundamental motive of the resource allocation is to allot the available resource in the most effective manner. In the initial phase, a representative resource usage distribution for a group of nodes with identical resource usage patterns is evaluated as resource bundle which can be easily employed to locate a group of nodes fulfilling a standard criterion. In the document, an innovative clustering-based resource aggregation viz. the Improved Hierarchal Agglomerative Clustering Algorithm (IHAC is elegantly launched to realize the compact illustration of a set of identically behaving nodes for scalability. In the subsequent phase concerned with energetic resource allocation procedure, the hybrid optimization technique is brilliantly brought in. The novel technique is devised for scheduling functions to cloud resources which duly consider both financial and evaluation expenses. The efficiency of the novel Resource allocation system is assessed by means of several parameters such the reliability, reusability and certain other metrics. The optimal path choice is the consequence of the hybrid optimization approach. The new-fangled technique allocates the available resource based on the optimal path.

  5. Improved Cat Swarm Optimization for Simultaneous Allocation of DSTATCOM and DGs in Distribution Systems

    Directory of Open Access Journals (Sweden)

    Neeraj Kanwar

    2015-01-01

    Full Text Available This paper addresses a new methodology for the simultaneous optimal allocation of DSTATCOM and DG in radial distribution systems to maximize power loss reduction while maintaining better node voltage profiles under multilevel load profile. Cat Swarm Optimization (CSO is one of the recently developed powerful swarm intelligence-based optimization techniques that mimics the natural behavior of cats but usually suffers from poor convergence and accuracy while subjected to large dimension problem. Therefore, an Improved CSO (ICSO technique is proposed to efficiently solve the problem where the seeking mode of CSO is modified to enhance its exploitation potential. In addition, the problem search space is virtually squeezed by suggesting an intelligent search approach which smartly scans the problem search space. Further, the effect of network reconfiguration has also been investigated after optimally placing DSTATCOMs and DGs in the distribution network. The suggested measures enhance the convergence and accuracy of the algorithm without loss of diversity. The proposed method is investigated on 69-bus test distribution system and the application results are very promising for the operation of smart distribution systems.

  6. Optimization

    CERN Document Server

    Pearce, Charles

    2009-01-01

    Focuses on mathematical structure, and on real-world applications. This book includes developments in several optimization-related topics such as decision theory, linear programming, turnpike theory, duality theory, convex analysis, and queuing theory.

  7. Improving Wishart Classification of Polarimetric SAR Data Using the Hopfield Neural Network Optimization Approach

    Directory of Open Access Journals (Sweden)

    Íñigo Molina

    2012-11-01

    Full Text Available This paper proposes the optimization relaxation approach based on the analogue Hopfield Neural Network (HNN for cluster refinement of pre-classified Polarimetric Synthetic Aperture Radar (PolSAR image data. We consider the initial classification provided by the maximum-likelihood classifier based on the complex Wishart distribution, which is then supplied to the HNN optimization approach. The goal is to improve the classification results obtained by the Wishart approach. The classification improvement is verified by computing a cluster separability coefficient and a measure of homogeneity within the clusters. During the HNN optimization process, for each iteration and for each pixel, two consistency coefficients are computed, taking into account two types of relations between the pixel under consideration and its corresponding neighbors. Based on these coefficients and on the information coming from the pixel itself, the pixel under study is re-classified. Different experiments are carried out to verify that the proposed approach outperforms other strategies, achieving the best results in terms of separability and a trade-off with the homogeneity preserving relevant structures in the image. The performance is also measured in terms of computational central processing unit (CPU times.

  8. Development of Pangasius steaks by improved sous-vide technology and its process optimization.

    Science.gov (United States)

    Kumari, Namita; Singh, Chongtham Baru; Kumar, Raushan; Martin Xavier, K A; Lekshmi, Manjusha; Venkateshwarlu, Gudipati; Balange, Amjad K

    2016-11-01

    The present study embarked on the objective of optimizing improved sous-vide processing condition for development of ready-to-cook Pangasius steaks with extended shelf-life using response surface methodology. For the development of improved sous-vide cooked product, Pangasius steaks were treated with additional hurdles in various combinations for optimization. Based on the study, suitable combination of chitosan and spices was selected which enhanced antimicrobial and oxidative stability of the product. The Box-Behnken experimental design with 15 trials per model was adopted for designing the experiment to know the effect of independent variables, namely chitosan concentration (X1), cooking time (X2) and cooking temperature (X3) on dependent variable i.e. TBARS value (Y1). From RSM generated model, the optimum condition for sous-vide processing of Pangasius steaks were 1.08% chitosan concentration, 70.93 °C of cooking temperature and 16.48 min for cooking time and predicted minimum value of multiple response optimal condition was Y = 0.855 mg MDA/Kg of fish. The high correlation coefficient (R(2) = 0.975) between the model and the experimental data showed that the model was able to efficiently predict processing condition for development of sous-vide processed Pangasius steaks. This research may help the processing industries and Pangasius fish farmer as it provides an alternative low cost technology for the proper utilization of Pangasius.

  9. The Parameters Optimization of MCR-WPT System Based on the Improved Genetic Simulated Annealing Algorithm

    Directory of Open Access Journals (Sweden)

    Sheng Lu

    2015-01-01

    Full Text Available To solve the problem of parameter selection during the design of magnetically coupled resonant wireless power transmission system (MCR-WPT, this paper proposed an improved genetic simulated annealing algorithm. Firstly, the equivalent circuit of the system is analysis in this study and a nonlinear programming mathematical model is built. Secondly, in place of the penalty function method in the genetic algorithm, the selection strategy based on the distance between individuals is adopted to select individual. In this way, it reduces the excess empirical parameters. Meanwhile, it can improve the convergence rate and the searching ability by calculating crossover probability and mutation probability according to the variance of population’s fitness. At last, the simulated annealing operator is added to increase local search ability of the method. The simulation shows that the improved method can break the limit of the local optimum solution and get the global optimum solution faster. The optimized system can achieve the practical requirements.

  10. An improved switching control law for the optimized synchronous electric charge extraction circuit

    Science.gov (United States)

    Liu, Weiqun; Badel, Adrien; Formosa, Fabien; Liu, Congzhi; Hu, Guangdi

    2015-12-01

    Nonlinear switching interface circuits are considered as an efficient way to improve the performance of vibration energy harvesters. Among the various approaches, OSECE (Optimized Synchronous Electric Charge Extraction) exhibits satisfying properties: simple switching strategy, good performance in low coupling cases and low load dependency. However, the overdamping induced by the voltage inversion at maximal points leads to performance degeneration in high coupling cases. This paper presents an improved switching control law for the OSECE technique. The new OSECE_PT (OSECE with switching Phase Tuning) technique presented here is to let the switches act ahead or after the maximal point with a phase tuning. Theoretical analysis and numerical simulations show that the OSECE_PT technique can improve the power performance effectively and preserves desired load independence properties.

  11. Cast Off expansion plan by rapid improvement through Optimization tool design, Tool Parameters and using Six Sigma’s ECRS Technique

    Science.gov (United States)

    Gopalakrishnan, T.; Saravanan, R.

    2017-03-01

    Powerful management concepts step-up the quality of the product, time saving in producing the product thereby increase the production rate, improves tools and techniques, work culture, work place and employee motivation and morale. In this paper discussed about the case study of optimizing the tool design, tool parameters to cast off expansion plan according ECRS technique. The proposed designs and optimal tool parameters yielded best results and meet the customer demand without expansion plan. Hence the work yielded huge savings of money (direct and indirect cost), time and improved the motivation and more of employees significantly.

  12. Improved cuckoo search with particle swarm optimization for classification of compressed images

    Indian Academy of Sciences (India)

    Vamsidhar Enireddy; Reddi Kiran Kumar

    2015-12-01

    The need for a general purpose Content Based Image Retrieval (CBIR) system for huge image databases has attracted information-technology researchers and institutions for CBIR techniques development. These techniques include image feature extraction, segmentation, feature mapping, representation, semantics, indexing and storage, image similarity-distance measurement and retrieval making CBIR system development a challenge. Since medical images are large in size running to megabits of data they are compressed to reduce their size for storage and transmission. This paper investigates medical image retrieval problem for compressed images. An improved image classification algorithm for CBIR is proposed. In the proposed method, RAW images are compressed using Haar wavelet. Features are extracted using Gabor filter and Sobel edge detector. The extracted features are classified using Partial Recurrent Neural Network (PRNN). Since training parameters in Neural Network are NP hard, a hybrid Particle Swarm Optimization (PSO) – Cuckoo Search algorithm (CS) is proposed to optimize the learning rate of the neural network.

  13. Optimization Solutions for Improving the Performance of the Parallel Reduction Algorithm Using Graphics Processing Units

    Directory of Open Access Journals (Sweden)

    Ion LUNGU

    2012-01-01

    Full Text Available In this paper, we research, analyze and develop optimization solutions for the parallel reduction function using graphics processing units (GPUs that implement the Compute Unified Device Architecture (CUDA, a modern and novel approach for improving the software performance of data processing applications and algorithms. Many of these applications and algorithms make use of the reduction function in their computational steps. After having designed the function and its algorithmic steps in CUDA, we have progressively developed and implemented optimization solutions for the reduction function. In order to confirm, test and evaluate the solutions' efficiency, we have developed a custom tailored benchmark suite. We have analyzed the obtained experimental results regarding: the comparison of the execution time and bandwidth when using graphic processing units covering the main CUDA architectures (Tesla GT200, Fermi GF100, Kepler GK104 and a central processing unit; the data type influence; the binary operator's influence.

  14. Three-dimensional Path Planning for Underwater Vehicles Based on an Improved Ant Colony Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    L.Yang

    2015-12-01

    Full Text Available Three-dimensional path planning for underwater vehicles is an important problem that focuses on optimizing the route with consideration of various constraints in a complex underwater environment. In this paper, an improved ant colony optimization (IACO algorithm based on pheromone exclusion is proposed to solve the underwater vehicle 3D path planning problem. The IACO algorithm can balance the tasks of exploration and development in the ant search path, and enable the ants in the search process to explore initially and develop subsequently. Then, the underwater vehicle can find the safe path by connecting the chosen nodes of the 3D mesh while avoiding the threat area. This new approach can overcome common disadvantages of the basic ant colony algorithm, such as falling into local extremum, poor quality, and low accuracy. Experimental comparative results demonstrate that this proposed IACO method is more effective and feasible in underwater vehicle 3D path planning than the basic ACO model.

  15. Optimal Restoration Scheduling of Damaged Networks Under Uncertain Environment by Using Improved Genetic Algorithm

    Institute of Scientific and Technical Information of China (English)

    Hitoshi FURUTA; Ken ISHIBASHI; Koichiro NAKATSU; Shun HOTTA

    2008-01-01

    The purpose of this research is to propose an early restoration for lifeline systems after earthquake disasters. The previous researches show that the optimization of the restoration schedule by using genetic algorithm (GA) is powerful. However, those are not considering the uncertain environment after earthquake disasters. The circumstances of the damage at devastated areas are very changeable due to the aftershock,fire disaster and bad weather. In addition, the restoring works may delay by unexpected accidents. Therefore,it is necessary to obtain the restoration schedule which has robustness, because the actual restoring works could not progress smoothly under the uncertain environment. GA considering uncertainty (GACU) can treat various uncertainties involved, but it is difficult to obtain the robust schedule. In this study, an attempt is made to develop a decision support system of the optimal restoration scheduling by using the improved GACU.

  16. Optimizing Antibiotic Stewardship in Nursing Homes: A Narrative Review and Recommendations for Improvement.

    Science.gov (United States)

    Crnich, Christopher J; Jump, Robin; Trautner, Barbara; Sloane, Philip D; Mody, Lona

    2015-09-01

    The emerging crisis in antibiotic resistance and concern that we now sit on the precipice of a post-antibiotic era have given rise to advocacy at the highest levels for widespread adoption of programmes that promote judicious use of antibiotics. These antibiotic stewardship programmes, which seek to optimize antibiotic choice when clinically indicated and discourage antibiotic use when clinically unnecessary, are being implemented in an increasing number of acute care facilities, but their adoption has been slower in nursing homes. The antibiotic prescribing process in nursing homes is fundamentally different from that observed in hospital and clinic settings, with formidable challenges to implementation of effective antibiotic stewardship. Nevertheless, an emerging body of research points towards ways to improve antibiotic prescribing practices in nursing homes. This review summarizes the findings of this research and presents ways in which antibiotic stewardship can be implemented and optimized in the nursing home setting.

  17. A Synchrophasor Based Optimal Voltage Control Scheme with Successive Voltage Stability Margin Improvement

    Directory of Open Access Journals (Sweden)

    Heng-Yi Su

    2016-01-01

    Full Text Available This paper proposes an optimal control scheme based on a synchronized phasor (synchrophasor for power system secondary voltage control. The framework covers voltage stability monitoring and control. Specifically, a voltage stability margin estimation algorithm is developed and built in the newly designed adaptive secondary voltage control (ASVC method to achieve more reliable and efficient voltage regulation in power systems. This new approach is applied to improve voltage profile across the entire power grid by an optimized plan for VAR (reactive power sources allocation; therefore, voltage stability margin of a power system can be increased to reduce the risk of voltage collapse. An extensive simulation study on the IEEE 30-bus test system is carried out to demonstrate the feasibility and effectiveness of the proposed scheme.

  18. Functionalized Scaffold-mediated Interleukin 10 Gene Delivery Significantly Improves Survival Rates of Stem Cells In Vivo

    Science.gov (United States)

    Holladay, Carolyn; Power, Karen; Sefton, Michael; O'Brien, Timothy; Gallagher, William M.; Pandit, Abhay

    2011-01-01

    While stem cell transplantation could potentially treat a variety of disorders, clinical studies have not yet demonstrated conclusive benefits. This may be partly because transplanted stem cells have low survival rates, potentially due to host inflammation. The system described herein used two different gene therapy techniques to improve retention of rat mesenchymal stem cells. In the first, stem cells were transfected with interleukin-10 (IL-10) before being loaded into a collagen scaffold. In the second, unmodified stem cells were loaded into a collagen scaffold along with polymer-complexed IL-10 plasmids. The scaffolds were surgically implanted into the dorsum of syngeneic rats. At each endpoint, the scaffolds were explanted and cell retention, IL-10 level and inflammatory response were quantified. All treatment groups had statistically significant increases in cell retention after 7 days, but the group treated with 2 µg of IL-10 polyplexes had a significant improvement even at 21 days. This cell retention was associated with increased IL-10 and decreased levels of proinflammatory cytokines and apoptosis. The primary effect on the inflammatory response appeared to be on macrophage differentiation, encouraging the regulatory phenotype over the cytotoxic lineage. Improving cell survival may be an important step toward realization of the therapeutic potential of stem cells. PMID:21266957

  19. Early Attempts to Eradicate Helicobacter pylori after Endoscopic Resection of Gastric Neoplasm Significantly Improve Eradication Success Rates

    Science.gov (United States)

    Huh, Cheal Wung; Youn, Young Hoon; Jung, Da Hyun; Park, Jae Jun; Kim, Jie-Hyun; Park, Hyojin

    2016-01-01

    Purpose After endoscopic resection (ER) of gastric tumors, eradication of Helicobacter pylori (H. pylori) infection is advised to reduce metachronous recurrence. Optimal timing of such therapy (yet to be established) was investigated herein, examining early active and late scarring stages of post-ER iatrogenic ulcers. Materials and Methods Analysis included 514 patients who received proton-pump inhibitor (PPI)-based triple therapy for H. pylori eradication after ER for gastric neoplasms between January 2008 and June 2015. Clinicopathologic characteristics, particularly the timing of triple therapy, were used to compare eradication rates, assigning patients to early- (≤2 weeks), intermediate- (2–8 weeks), and late-phase (≥8 weeks) treatment groups. Results H. pylori eradication rates differed significantly by timing of triple therapy after ER (early, 90.0%; intermediate, 76.2%, late, 72.4%; p ulcer, and duration of therapeutic regimen. Early initiation of H. pylori eradication was also identified as a significant independent predictor of eradication success in multivariate analysis (Odds ratio = 3.67, 95% CI 2.18–6.16; p <.001). Conclusion In patients undergoing ER of gastric tumors, early post-ER attempts at eradication of H. pylori offer the best chance of eradication success. PMID:27588679

  20. Medium Optimization for Improved Ethanol Production in Very High Gravity Fermentation

    Institute of Scientific and Technical Information of China (English)

    胡纯铿; 秦晴; 高培培

    2011-01-01

    An optimal medium (300 g·L^-1 initial glucose) comprising 6.3 mmol·L^-1 Mg2+, 5.0 mmol·L^-1 Ca2+, 15.0 g·L^-1 peptone and 21.5 g·L^-1 yeast extract was determined by uniform design to improve very high gravity (VHG) ethanol fermentation, showing over 30% increase in final ethanol (from 13.1% to 17.1%, by volume), 29% decrease in fermentation time (from 84 to 60 h), 80% increase in biomass formation and 26% increase in glucose utilization. Experiments also revealed physiological aspects linked to the fermentation enhancements. Compared to the control, trehalose in the cells grown in optimal fermentation medium increased 17.9-, 2.8-, 1.9-, 1.8- and 1.9-fold at the fermentation time of 12, 24, 36, 48 and 60 h, respectively. Its sharp rise at the early stage of fermentation when there was a considerable osmotic stress suggested that trehalose played an important role in promoting fermentation. Meanwhile, at the identical five fermentation time, the plasma membrane ATPase activity of the cells grown in optimal medium was 2.3, 1.8, 1.6, 1.5 and 1.3 times that of the control, respectively. Their disparities in enzymatic activity became wider when the glucose levels were dramatically changed for ethanol production, suggesting this enzyme also contributed to the fermentation improvements. Thus, medium optimization for VHG ethanol fermentation was found to trigger the increased yeast trehalose accumulation and plasma membrane ATPase activity.

  1. Optimization of photonic crystal cavities

    DEFF Research Database (Denmark)

    Wang, Fengwen; Sigmund, Ole

    2017-01-01

    We present optimization of photonic crystal cavities. The optimization problem is formulated to maximize the Purcell factor of a photonic crystal cavity. Both topology optimization and air-hole-based shape optimization are utilized for the design process. Numerical results demonstrate...... that the Purcell factor of the photonic crystal cavity can be significantly improved through optimization....

  2. Improvement of antibiotic activity of Xenorhabdus bovienii by medium optimization using response surface methodology

    Science.gov (United States)

    2011-01-01

    Background The production of secondary metabolites with antibiotic properties is a common characteristic to entomopathogenic bacteria Xenorhabdus spp. These metabolites not only have diverse chemical structures but also have a wide range of bioactivities with medicinal and agricultural interests such as antibiotic, antimycotic and insecticidal, nematicidal and antiulcer, antineoplastic and antiviral. It has been known that cultivation parameters are critical to the secondary metabolites produced by microorganisms. Even small changes in the culture medium may not only impact the quantity of certain compounds but also the general metabolic profile of microorganisms. Manipulating nutritional or environmental factors can promote the biosynthesis of secondary metabolites and thus facilitate the discovery of new natural products. This work was conducted to evaluate the influence of nutrition on the antibiotic production of X. bovienii YL002 and to optimize the medium to maximize its antibiotic production. Results Nutrition has high influence on the antibiotic production of X. bovienii YL002. Glycerol and soytone were identified as the best carbon and nitrogen sources that significantly affected the antibiotic production using one-factor-at-a-time approach. Response surface methodology (RSM) was applied to optimize the medium constituents (glycerol, soytone and minerals) for the antibiotic production of X. bovienii YL002. Higher antibiotic activity (337.5 U/mL) was obtained after optimization. The optimal levels of medium components were (g/L): glycerol 6.90, soytone 25.17, MgSO4·7H2O 1.57, (NH4)2SO4 2.55, KH2PO4 0.87, K2HPO4 1.11 and Na2SO4 1.81. An overall of 37.8% increase in the antibiotic activity of X. bovienii YL002 was obtained compared with that of the original medium. Conclusions To the best of our knowledge, there are no reports on antibiotic production of X. boviebii by medium optimization using RSM. The results strongly support the use of RSM for medium

  3. An Improved Artificial Bee Colony Algorithm and Its Application to Multi-Objective Optimal Power Flow

    Directory of Open Access Journals (Sweden)

    Xuanhu He

    2015-03-01

    Full Text Available Optimal power flow (OPF objective functions involve minimization of the total fuel costs of generating units, minimization of atmospheric pollutant emissions, minimization of active power losses and minimization of voltage deviations. In this paper, a fuzzy multi-objective OPF model is established by the fuzzy membership functions and the fuzzy satisfaction-maximizing method. The improved artificial bee colony (IABC algorithm is applied to solve the model. In the IABC algorithm, the mutation and crossover operations of a differential evolution algorithm are utilized to generate new solutions to improve exploitation capacity; tent chaos mapping is utilized to generate initial swarms, reference mutation solutions and the reference dimensions of crossover operations to improve swarm diversity. The proposed method is applied to multi-objective OPF problems in IEEE 30-bus, IEEE 57-bus and IEEE 300-bus test systems. The results are compared with those obtained by other algorithms, which demonstrates the effectiveness and superiority of the IABC algorithm, and how the optimal scheme obtained by the proposed model can make systems more economical and stable.

  4. A simple and green route to transparent boron nitride/PVA nanocomposites with significantly improved mechanical and thermal properties

    Institute of Scientific and Technical Information of China (English)

    Zhi-Qiang Duan; Yi-Tao Liu; Xu-Ming Xie; Xiong-Ying Ye

    2013-01-01

    A simple and green method is developed to prepare hexagonal boron nitride (h-BN)/poly(vinyl alcohol) (PVA) nanocomposites by using water as a common solvent of h-BN nanosheets and PVA.The obtained hBN/PVA nanocomposites are highly transparent,and have significantly improved mechanical and thermal properties.They may outperform nano-clay and nano-alumina/PVA nanocomposites as flexible optoelectronic devices,optical windows and heat-releasing materials operated in oxidative or corrosive environment.

  5. Unit Risk Quotient (RQ) and Relative Significance of Radionuclide on Flora and Fauna to the EU-APR Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Keunsung [KHNP-CRI, Daejeon (Korea, Republic of); Kim, Sukhoon [FNC Technology Co., Ltd., Yongin (Korea, Republic of); Lee, Chonghui [KEPCO E and C, Yongin (Korea, Republic of)

    2015-05-15

    As part of the project for acquiring the certification from EUR organization, in accordance with Articles 4.8 and 5.5 specified in Section 2.20 of EUR Volume 2, the effects of ionizing radiation from the standard design of EU-APR on biota and ecosystems during operation and decommissioning phases shall be assessed. This assessment must be carried out according to the ERICA (i.e. Environmental Risk from Ionizing Contaminants: Assessment and management) integrated approach. This paper describes the evaluation results for unit risk quotient and relative significance by radionuclide derived from performing Tier 1 assessment on flora and fauna for the EU-APR design using ERICA Tool. As specified previously, Pa-231 and Th-228 are the most significant for the terrestrial and for the marine/freshwater ecosystems, respectively. And, in terms of environmental risk, those radionuclides having the most impact on flora and fauna are relatively more significant than isotope having the least impact by about 7 to 10 orders of magnitude.

  6. Optimization of caseinate-coated simvastatin-zein nanoparticles: improved bioavailability and modified release characteristics

    Directory of Open Access Journals (Sweden)

    Ahmed OA

    2015-01-01

    Full Text Available Osama AA Ahmed,1,2 Khaled M Hosny,1,3 Majid M Al-Sawahli,1,4 Usama A Fahmy11Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Minia University, Minia, Egypt; 3Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Beni Suef University, Beni Suef, Egypt; 4Holding Company for Biological Products & Vaccines (VACSERA, Cairo, EgyptAbstract: The current study focuses on utilization of the natural biocompatible polymer zein to formulate simvastatin (SMV nanoparticles coated with caseinate, to improve solubility and hence bioavailability, and in addition, to modify SMV-release characteristics. This formulation can be utilized for oral or possible depot parenteral applications. Fifteen formulations were prepared by liquid–liquid phase separation method, according to the Box–Behnken design, to optimize formulation variables. Sodium caseinate was used as an electrosteric stabilizer. The factors studied were: percentage of SMV in the SMV-zein mixture (X1, ethanol concentration (X2, and caseinate concentration (X3. The selected dependent variables were mean particle size (Y1, SMV encapsulation efficiency (Y2, and cumulative percentage of drug permeated after 1 hour (Y3. The diffusion of SMV from the prepared nanoparticles specified by the design was carried out using an automated Franz diffusion cell apparatus. The optimized SMV-zein formula was investigated for in vivo pharmacokinetic parameters compared with an oral SMV suspension. The optimized nanosized SMV-zein formula showed a 131 nm mean particle size and 89% encapsulation efficiency. In vitro permeation studies displayed delayed permeation characteristics, with about 42% and 85% of SMV cumulative amount released after 12 and 48 hours, respectively. Bioavailability estimation in rats revealed an augmentation in SMV bioavailability

  7. Improvement of the energy resolution via an optimized digital signal processing in GERDA Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, M.; Bode, T.; Budjas, D.; Janicsko Csathy, J.; Lazzaro, A.; Schoenert, S. [Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); Allardt, M.; Domula, A.; Lehnert, B.; Schneider, B.; Wester, T.; Wilsenach, H.; Zuber, K. [Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany); Bakalyarov, A.M.; Belyaev, S.T.; Lebedev, V.I.; Zhukov, S.V. [National Research Center ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Balata, M.; D' Andrea, V.; Di Vacri, A.; Junker, M.; Laubenstein, M.; Macolino, C.; Zavarise, P. [LNGS, Assergi (Italy); Barabanov, I.; Bezrukov, L.; Doroshkevich, E.; Fedorova, O.; Gurentsov, V.; Kazalov, V.; Kuzminov, V.V.; Lubsandorzhiev, B.; Moseev, P.; Selivanenko, O.; Veresnikova, A.; Yanovich, E. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Barros, N. [Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany); University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, PA (United States); Baudis, L.; Benato, G.; Walter, M. [Physik Institut der Universitaet Zuerich, Zurich (Switzerland); Bauer, C.; Heisel, M.; Heusser, G.; Hofmann, W.; Kihm, T.; Kirsch, A.; Knoepfle, K.T.; Lindner, M.; Maneschg, W.; Salathe, M.; Schreiner, J.; Schwingenheuer, B.; Simgen, H.; Smolnikov, A.; Stepaniuk, M.; Wagner, V.; Wegmann, A. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Becerici-Schmidt, N.; Caldwell, A.; Liao, H.Y.; Majorovits, B.; Palioselitis, D.; Schulz, O.; Vanhoefer, L. [Max-Planck-Institut fuer Physik, Munich (Germany); Bellotti, E. [Universita Milano Bicocca, Dipartimento di Fisica, Milan (Italy); INFN Milano Bicocca, Milan (Italy); Belogurov, S.; Kornoukhov, V.N. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bettini, A.; Brugnera, R.; Garfagnini, A.; Hemmer, S.; Medinaceli, E.; Sada, C.; Sturm, K. von [Universita di Padova, Dipartimento di Fisica e Astronomia, Padua (Italy); INFN Padova, Padua (Italy); Borowicz, D. [Jagiellonian University, Institute of Physics, Krakow (Poland); Joint Institute for Nuclear Research, Dubna (Russian Federation); Brudanin, V.; Egorov, V.; Kochetov, O.; Nemchenok, I.; Rumyantseva, N.; Zhitnikov, I.; Zinatulina, D. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Cattadori, C. [INFN Milano Bicocca, Milan (Italy); Chernogorov, A.; Demidova, E.V.; Kirpichnikov, I.V.; Vasenko, A.A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Falkenstein, R.; Freund, K.; Grabmayr, P.; Hegai, A.; Jochum, J.; Schmitt, C.; Schuetz, A.K. [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Frodyma, N.; Misiaszek, M.; Panas, K.; Pelczar, K.; Wojcik, M.; Zuzel, G. [Jagiellonian University, Institute of Physics, Krakow (Poland); Gangapshev, A. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Gusev, K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Center ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); Hult, M.; Lutter, G. [Institute for Reference Materials and Measurements, Geel (Belgium); Inzhechik, L.V. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Moscow (Russian Federation); Klimenko, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); International University for Nature, Society and Man ' ' Dubna' ' , Dubna (Russian Federation); Lippi, I.; Stanco, L.; Ur, C.A. [INFN Padova, Padua (Italy); Lubashevskiy, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Pandola, L. [INFN Laboratori Nazionali del Sud, Catania (Italy); Pullia, A.; Riboldi, S. [Universita degli Studi di Milano, Dipartimento di Fisica, Milan (Italy); INFN, Milano (Italy); Shirchenko, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Center ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Collaboration: GERDA Collaboration

    2015-06-15

    An optimized digital shaping filter has been developed for the Gerda experiment which searches for neutrinoless double beta decay in {sup 76}Ge. The GERDA Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) corresponding to 10% at the Q value for 0νββ decay in {sup 76}Ge is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping filter. (orig.)

  8. Improving the content uniformity of a low-dose tablet formulation through roller compaction optimization.

    Science.gov (United States)

    am Ende, Mary T; Moses, Sara K; Carella, Anthony J; Gadkari, Rashmi A; Graul, Timothy W; Otano, Angel L; Timpano, Robert J

    2007-01-01

    In this investigation, the potency distribution of a low-dose drug in a granulation was optimized through a two-part study using statistically designed experiments. The purpose of this investigation was to minimize the segregation potential by improving content uniformity across the granule particle size distribution, thereby improving content uniformity in the tablet. Initial operating parameters on the Gerteis 3-W-Polygran 250/100/3 Roller Compactor resulted in a U-shaped potency function (potency vs. granule particle size) with superpotent fines and large granules. The roller compaction optimization study was carried out in two parts. Study I used a full factorial design with roll force (RF) and average gap width (GW) as independent variables and Study II used a D-optimal response surface design with four factors: RF, GW, granulating sieve size (SS), and granulator speed (GS). The planned response variables for Study I were bypass weight % and potency of bypass. Response variables for Study II included mean granulation potency with % relative standard deviation (% RSD), granulation particle size, sieve cut potency % RSD, tablet potency with % RSD, compression force at 7 kP crushing strength, and friability of 7-kP tablets. A constraint on GW was determined in Study I by statistical analysis. Bypass and observations of ribbon splitting were minimized when GW was less than 2.6 mm. In Study II, granulation potency, granulation uniformity, and sieve cut uniformity were optimized when the SS was 0.8 mm. Higher RF during dry granulation produced better sieve cut uniformity and tablets with improved uniformity throughout the run, as measured by stratified tablet samples taken during compression and assayed for potency. The recommended optimum roller compaction and milling operating parameters that simultaneously met all constraints were RF = 9 kN, GW = 2.3 mm, SS = 0.8 mm, and GS = 50 rpm. These parameters became the operating parameter set points during a model

  9. Muscle synergies may improve optimization prediction of knee contact forces during walking.

    Science.gov (United States)

    Walter, Jonathan P; Kinney, Allison L; Banks, Scott A; D'Lima, Darryl D; Besier, Thor F; Lloyd, David G; Fregly, Benjamin J

    2014-02-01

    The ability to predict patient-specific joint contact and muscle forces accurately could improve the treatment of walking-related disorders. Muscle synergy analysis, which decomposes a large number of muscle electromyographic (EMG) signals into a small number of synergy control signals, could reduce the dimensionality and thus redundancy of the muscle and contact force prediction process. This study investigated whether use of subject-specific synergy controls can improve optimization prediction of knee contact forces during walking. To generate the predictions, we performed mixed dynamic muscle force optimizations (i.e., inverse skeletal dynamics with forward muscle activation and contraction dynamics) using data collected from a subject implanted with a force-measuring knee replacement. Twelve optimization problems (three cases with four subcases each) that minimized the sum of squares of muscle excitations were formulated to investigate how synergy controls affect knee contact force predictions. The three cases were: (1) Calibrate+Match where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously matched, (2) Precalibrate+Predict where experimental knee contact forces were predicted using precalibrated muscle model parameters values from the first case, and (3) Calibrate+Predict where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously predicted, all while matching inverse dynamic loads at the hip, knee, and ankle. The four subcases used either 44 independent controls or five synergy controls with and without EMG shape tracking. For the Calibrate+Match case, all four subcases closely reproduced the measured medial and lateral knee contact forces (R2 ≥ 0.94, root-mean-square (RMS) error force prediction. For the Precalibrate+Predict and Calibrate+Predict cases, synergy controls yielded better contact force predictions (0.61 force predictions improved when

  10. Improvement of the energy resolution via an optimized digital signal processing in GERDA Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, M. [Physik Department and Excellence Cluster Universe, Technische Universität München, Munich (Germany); Allardt, M. [Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden (Germany); Bakalyarov, A. M. [National Research Center “Kurchatov Institute”, Moscow (Russian Federation); Balata, M. [INFN Laboratori Nazionali del Gran Sasso, LNGS, and Gran Sasso Science Institute, GSSI, Assergi (Italy); Collaboration: GERDA Collaboration; and others

    2015-06-09

    An optimized digital shaping filter has been developed for the Gerda experiment which searches for neutrinoless double beta decay in {sup 76}Ge. The Gerda Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) corresponding to 10 % at the Q value for 0νββ decay in {sup 76}Ge is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping filter.

  11. Integrating digital image management software for improved patient care and optimal practice management.

    Science.gov (United States)

    Starr, Jon C

    2006-06-01

    Photographic images provide vital documentation of preoperative, intraoperative, and postoperative results in the clinical dermatologic surgery practice and can document histologic findings from skin biopsies, thereby enhancing patient care. Images may be printed as part of text documents, transmitted via electronic mail, or included in electronic medical records. To describe existing computer software that integrates digital photography and the medical record to improve patient care and practice management. A variety of computer applications are available to optimize the use of digital images in the dermatologic practice.

  12. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle;

    1998-01-01

    therefore been developed. The system is implemented as a complement, producing control signals to be added to those of the existing boiler control system, a concept which has various practical advantages in terms of implementation and commissioning. The optimizing control system takes account...... of the multivariable and load-de*pendent nonlinear characteristics of the boiler process, as a scheduled LQG controller with feedforward action is utilized. The LQG controller improves the control of critical pro*cess variables, making it possible to increase the load-following capability of a specific plant. Field...

  13. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle;

    therefore been developed. The system is implemented as a complement, producing control signals to be added to those of the existing boiler control system, a concept which has various practical advantages in terms of implementation and commissioning. The optimizing control system takes account...... of the multivariable and load-de*pendent nonlinear characteristics of the boiler process, as a scheduled LQG controller with feedforward action is utilized. The LQG controller improves the control of critical pro*cess variables, making it possible to increase the load-following capability of a specific plant. Field...

  14. A Time-Domain Structural Damage Detection Method Based on Improved Multiparticle Swarm Coevolution Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Shao-Fei Jiang

    2014-01-01

    Full Text Available Optimization techniques have been applied to structural health monitoring and damage detection of civil infrastructures for two decades. The standard particle swarm optimization (PSO is easy to fall into the local optimum and such deficiency also exists in the multiparticle swarm coevolution optimization (MPSCO. This paper presents an improved MPSCO algorithm (IMPSCO firstly and then integrates it with Newmark’s algorithm to localize and quantify the structural damage by using the damage threshold proposed. To validate the proposed method, a numerical simulation and an experimental study of a seven-story steel frame were employed finally, and a comparison was made between the proposed method and the genetic algorithm (GA. The results show threefold: (1 the proposed method not only is capable of localization and quantification of damage, but also has good noise-tolerance; (2 the damage location can be accurately detected using the damage threshold proposed in this paper; and (3 compared with the GA, the IMPSCO algorithm is more efficient and accurate for damage detection problems in general. This implies that the proposed method is applicable and effective in the community of damage detection and structural health monitoring.

  15. Optimal cost and allocation for UPFC using HRGAPSO to improve power system security and loadability

    Energy Technology Data Exchange (ETDEWEB)

    Marouani, I.; Guesmi, T.; Hadj Abdallah, H.; Ouali, A. [Sfax Engineering National School, Electrical Department, BP: W, 3038 Sfax (Tunisia)

    2011-07-01

    With the electricity market deregulation, the number of unplanned power exchanges increases. Some lines located on particular paths may become overload. It is advisable for the transmission system operator to have another way of controlling power flows in order to permit a more efficient and secure use of transmission lines. The FACTS devices (Flexible AC Transmission Systems) could be a mean to carry out this function. In this paper, unified power flow controller (UPFC) is located in order to maximize the system loadability and index security. The optimization problem is solved using a new evolutionary learning algorithm based on a hybrid of real genetic algorithm (RGA) and particle swarm optimization (PSO) called HRGAPSO. The Newton-Raphson load flow algorithm is modified to consider the insertion of the UPFC devices in the network. Simulations results validate the efficiency of this approach to improvement in security, reduction in losses of power system, minimizing the installation cost of UPFC and increasing power transfer capability of the existing power transmission lines. The optimization results was performed on 14-bus test system and implemented using MATLAB.

  16. A multi-criteria optimization and decision-making approach for improvement of food engineering processes

    Directory of Open Access Journals (Sweden)

    Alik Abakarov

    2013-04-01

    Full Text Available The objective of this study was to propose a multi-criteria optimization and decision-making technique to solve food engineering problems. This technique was demonstrated using experimental data obtained on osmotic dehydration of carrot cubes in a sodium chloride solution. The Aggregating Functions Approach, the Adaptive Random Search Algorithm, and the Penalty Functions Approach were used in this study to compute the initial set of non-dominated or Pareto-optimal solutions. Multiple non-linear regression analysis was performed on a set of experimental data in order to obtain particular multi-objective functions (responses, namely water loss, solute gain, rehydration ratio, three different colour criteria of rehydrated product, and sensory evaluation (organoleptic quality. Two multi-criteria decision-making approaches, the Analytic Hierarchy Process (AHP and the Tabular Method (TM, were used simultaneously to choose the best alternative among the set of non-dominated solutions. The multi-criteria optimization and decision-making technique proposed in this study can facilitate the assessment of criteria weights, giving rise to a fairer, more consistent, and adequate final compromised solution or food process. This technique can be useful to food scientists in research and education, as well as to engineers involved in the improvement of a variety of food engineering processes.

  17. Optimal cost and allocation for UPFC using HRGAPSO to improve power system security and loadability

    Directory of Open Access Journals (Sweden)

    Marouani I., Guesmi T., Hadj Abdallah H., Ouali A.

    2011-09-01

    Full Text Available With the electricity market deregulation, the number of unplanned power exchanges increases. Some lines located on particular paths may become overload. It is advisable for the transmission system operator to have another way of controlling power flows in order to permit a more efficient and secure use of transmission lines. The FACTS devices (Flexible AC Transmission Systems could be a mean to carry out this function. In this paper, unified power flow controller (UPFC is located in order to maximize the system loadability and index security. The optimization problem is solved using a new evolutionary learning algorithm based on a hybrid of real genetic algorithm (RGA and particle swarm optimization (PSO called HRGAPSO. The Newton-Raphson load flow algorithm is modified to consider the insertion of the UPFC devices in the network. Simulations results validate the efficiency of this approach to improvement in security, reduction in losses of power system, minimizing the installation cost of UPFC and increasing power transfer capability of the existing power transmission lines. The optimization results was performed on 14-bus test system and implemented using MATLAB.

  18. Spinning Reserve Requirements Optimization Based on an Improved Multiscenario Risk Analysis Method

    Directory of Open Access Journals (Sweden)

    Liudong Zhang

    2017-01-01

    Full Text Available This paper proposes a novel security-constrained unit commitment model to calculate the optimal spinning reserve (SR amount. The model combines cost-benefit analysis with an improved multiscenario risk analysis method capable of considering various uncertainties, including load and wind power forecast errors as well as forced outages of generators. In this model, cost-benefit analysis is utilized to simultaneously minimize the operation cost of conventional generators, the expected cost of load shedding, the penalty cost of wind power spillage, and the carbon emission cost. It remedies the defects of the deterministic and probabilistic methods of SR calculation. In cases where load and wind power generation are negatively correlated, this model based on multistep modeling of net demand can consider the wind power curtailment to maximize the overall economic efficiency of system operation so that the optimal economic values of wind power and SR are achieved. In addition, the impact of the nonnormal probability distributions of wind power forecast error on SR optimization can be taken into account. Using mixed integer linear programming method, simulation studies on a modified IEEE 26-generator reliability test system connected to a wind farm are performed to confirm the effectiveness and advantage of the proposed model.

  19. An Improved Harmony Search Based on Teaching-Learning Strategy for Unconstrained Optimization Problems

    Directory of Open Access Journals (Sweden)

    Shouheng Tuo

    2013-01-01

    Full Text Available Harmony search (HS algorithm is an emerging population-based metaheuristic algorithm, which is inspired by the music improvisation process. The HS method has been developed rapidly and applied widely during the past decade. In this paper, an improved global harmony search algorithm, named harmony search based on teaching-learning (HSTL, is presented for high dimension complex optimization problems. In HSTL algorithm, four strategies (harmony memory consideration, teaching-learning strategy, local pitch adjusting, and random mutation are employed to maintain the proper balance between convergence and population diversity, and dynamic strategy is adopted to change the parameters. The proposed HSTL algorithm is investigated and compared with three other state-of-the-art HS optimization algorithms. Furthermore, to demonstrate the robustness and convergence, the success rate and convergence analysis is also studied. The experimental results of 31 complex benchmark functions demonstrate that the HSTL method has strong convergence and robustness and has better balance capacity of space exploration and local exploitation on high dimension complex optimization problems.

  20. Energetic optimization as a result of improvement for social comfort: international example

    Energy Technology Data Exchange (ETDEWEB)

    Melandri, D.

    2007-07-01

    Comfort of human beings is related to the availability of energetic sources. In these terms, connection between comfort and energy becomes synonymous of connection between comfort and productivity. Thus Energy Management can be considered as a tool to optimize different parameters, with clear results on global efficiency of all processes. A clear energetic analysis, besides standard evaluation, can bring to optimization of following parameters: Lay out, Human resources, Internal logistic processes, Business productivity. Through energetic cost, for example, it is possible to have reference indicators useful for the lay out and number of employees optimization in offices. An International study has been conducted in this sense, with important and surprising results. A design for a building in Australia shows that an excellent energetic efficiency brings to an annual saving of 10 ml dollars, as a result of the improved efficiency of the working area. Similar examples can be found in several parts of the world. For these reasons, in civil and tertiary sector, some important pollution causes must be considered during the design of energy efficiency systems: atmospheric pollution due to chemical agents and radiations, acoustic pollution, vibration pollution, microclimate states, lighting. All these elements are part of the study. (auth)

  1. Review of improved Monte Carlo methods in uncertainty-based design optimization for aerospace vehicles

    Science.gov (United States)

    Hu, Xingzhi; Chen, Xiaoqian; Parks, Geoffrey T.; Yao, Wen

    2016-10-01

    Ever-increasing demands of uncertainty-based design, analysis, and optimization in aerospace vehicles motivate the development of Monte Carlo methods with wide adaptability and high accuracy. This paper presents a comprehensive review of typical improved Monte Carlo methods and summarizes their characteristics to aid the uncertainty-based multidisciplinary design optimization (UMDO). Among them, Bayesian inference aims to tackle the problems with the availability of prior information like measurement data. Importance sampling (IS) settles the inconvenient sampling and difficult propagation through the incorporation of an intermediate importance distribution or sequential distributions. Optimized Latin hypercube sampling (OLHS) is a stratified sampling approach to achieving better space-filling and non-collapsing characteristics. Meta-modeling approximation based on Monte Carlo saves the computational cost by using cheap meta-models for the output response. All the reviewed methods are illustrated by corresponding aerospace applications, which are compared to show their techniques and usefulness in UMDO, thus providing a beneficial reference for future theoretical and applied research.

  2. Improving the Performance of Dynamic Source Routing Protocol by Optimization of Neural Networks

    Directory of Open Access Journals (Sweden)

    Rajesh Gargi

    2012-07-01

    Full Text Available Dynamic Source Routing protocol is one of the most promising among on demand category of protocols for MANETs. Demands of network performance conflict with the demands of mobile networks . To enhance the QoS in a protocol like DSR we used ANN which helps to preserve the resources of the MANET leading to improvement in performance of DSR. While routing the data, If a legitimate node is mistaken as rogue node then also the QoS suffers and if a rogue node is not detected then also it can consume the resources of the network and deteriorate the QoS . In this work a neural network has been further optimized to improve its accuracy by varying the number of layers in it. A typical wireless network scenario of DSR has been simulated in NS2 and then a rogue node has been introduced to mimic attack. The parameters from the trace files have been used to train a neural network simulated in Matlab and its effectiveness has been improved to make the detection of intrusion more accurate. Although previous work has been reported in the area of application of neural networks for intrusion detection but there is a scope of improvement in this technique by varying the number of layers of ANN, making it more effective and improving the QoS of MANET.

  3. Improving CCTA-based lesions' hemodynamic significance assessment by accounting for partial volume modeling in automatic coronary lumen segmentation.

    Science.gov (United States)

    Freiman, Moti; Nickisch, Hannes; Prevrhal, Sven; Schmitt, Holger; Vembar, Mani; Maurovich-Horvat, Pál; Donnelly, Patrick; Goshen, Liran

    2017-03-01

    The goal of this study was to assess the potential added benefit of accounting for partial volume effects (PVE) in an automatic coronary lumen segmentation algorithm that is used to determine the hemodynamic significance of a coronary artery stenosis from coronary computed tomography angiography (CCTA). Two sets of data were used in our work: (a) multivendor CCTA datasets of 18 subjects from the MICCAI 2012 challenge with automatically generated centerlines and 3 reference segmentations of 78 coronary segments and (b) additional CCTA datasets of 97 subjects with 132 coronary lesions that had invasive reference standard FFR measurements. We extracted the coronary artery centerlines for the 97 datasets by an automated software program followed by manual correction if required. An automatic machine-learning-based algorithm segmented the coronary tree with and without accounting for the PVE. We obtained CCTA-based FFR measurements using a flow simulation in the coronary trees that were generated by the automatic algorithm with and without accounting for PVE. We assessed the potential added value of PVE integration as a part of the automatic coronary lumen segmentation algorithm by means of segmentation accuracy using the MICCAI 2012 challenge framework and by means of flow simulation overall accuracy, sensitivity, specificity, negative and positive predictive values, and the receiver operated characteristic (ROC) area under the curve. We also evaluated the potential benefit of accounting for PVE in automatic segmentation for flow simulation for lesions that were diagnosed as obstructive based on CCTA which could have indicated a need for an invasive exam and revascularization. Our segmentation algorithm improves the maximal surface distance error by ~39% compared to previously published method on the 18 datasets from the MICCAI 2012 challenge with comparable Dice and mean surface distance. Results with and without accounting for PVE were comparable. In contrast

  4. RH-01THE SIGNIFICANCE OF ACUTE INPATIENT REHABILITATION FOR GLIOMA PATIENTS: IMPROVING THE PHYSICAL FUNCTION, QUALITY OF LIFE AND SURVIVAL

    Science.gov (United States)

    Beverly Fu, D.; Bota, Daniela A.

    2014-01-01

    OBJECTIVE: To assess the effects of inpatient acute rehabilitation on overall function, quality of life and overall survival for glioma patients. DESIGN: A retrospective study of glioma patients treated at UCI Neuro-Oncology Program. PARTICIPANTS: We have identified 12 patients with glioma diagnosis who underwent inpatient acute rehabilitation program using our IRB approved neuro-oncology database. OUTCOME ASSESSMENT TOOLS: Functional status based upon Karnofsky performance scale (KPS), quality of life as assessed by Functional Assessment of Cancer Therapy Brain (FACT-Br) and overall survival. RESULTS: We identified on our study 3 patients with glioblastoma, 7 patients with anaplastic gliomas, and 2 patients with low grade gliomas. All of them had radiation and chemotherapy, except 2 patients with low grade gliomas who had radiation treatment only. The age range is from 26 to 77 and the mean age is 49-year-old. All the patients who underwent the acute inpatient rehabilitation program at our institution, not only improved their KPS scale significantly, but also enhanced their social and emotional well-being. The median KPS improvement is 30 points from a 3-6 weeks stay. Functional Assessment of Cancer Therapy Brain (FACT-Br) is obtained from 4 patients at this time (further information will be presented at SNO conference). The mean FACT-Br TOI is 60.8, and the total FACT0Br Score is 119.6. Survival data are still collected. CONCLUSIONS: The patients who underwent acute inpatient rehabilitation program, showed significant improvements in their functional status and quality of life. The observation from this pilot study warrants further research and demonstrates the acute inpatient rehabilitation may be beneficial to glioma patients with good physical functions and tolerance for 3 hours a day of physical, occupation and speech therapies.

  5. Statistical Optimization of Medium Components for Improved Product Ion of Recombinant Hyperthermophilic Esterase

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The optimization of nutrient levels for the production of recombinant hyperthermophilic esterase by E. coli was carried out with response surface methodology(RSM) based on the central composite rotatable design(CCRD). A 24central composite rotatable design was used to study the combined effect of the nutritional constituents like yeast extract, peptone, mineral salt and trace metals. The P-value of the coefficient for the linear effect of peptone concentration was 0. 0081 and trace metals solution was less than 0. 0001, suggesting that these were the principal variables with significant effect on the hyperthermophilic esterase production. The predicted optimal hyperthermophilic esterase yield was 269. 17 U/mL, whereas an actual experimental value of 284. 58 U/mL was obtained.

  6. DEVELOPMENT AND OPTIMIZATION OF GAS-ASSISTED GRAVITY DRAINAGE (GAGD) PROCESS FOR IMPROVED LIGHT OIL RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    Dandina N. Rao; Subhash C. Ayirala; Madhav M. Kulkarni; Thaer N.N. Mahmoud; Wagirin Ruiz Paidin

    2006-01-01

    This report describes the progress of the project ''Development And Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery'' for the duration of the thirteenth project quarter (Oct 1, 2005 to Dec 30, 2005). There are three main tasks in this research project. Task 1 is a scaled physical model study of the GAGD process. Task 2 is further development of a vanishing interfacial tension (VIT) technique for miscibility determination. Task 3 is determination of multiphase displacement characteristics in reservoir rocks. Section I reports experimental work designed to investigate wettability effects of porous medium, on secondary and tertiary mode GAGD performance. The experiments showed a significant improvement of oil recovery in the oil-wet experiments versus the water-wet runs, both in secondary as well as tertiary mode. When comparing experiments conducted in secondary mode to those run in tertiary mode an improvement in oil recovery was also evident. Additionally, this section summarizes progress made with regard to the scaled physical model construction and experimentation. The purpose of building a scaled physical model, which attempts to include various multiphase mechanics and fluid dynamic parameters operational in the field scale, was to incorporate visual verification of the gas front for viscous instabilities, capillary fingering, and stable displacement. Preliminary experimentation suggested that construction of the 2-D model from sintered glass beads was a feasible alternative. During this reporting quarter, several sintered glass mini-models were prepared and some preliminary experiments designed to visualize gas bubble development were completed. In Section II, the gas-oil interfacial tensions measured in decane-CO{sub 2} system at 100 F and live decane consisting of 25 mole% methane, 30 mole% n-butane and 45 mole% n-decane against CO{sub 2} gas at 160 F have been modeled using the Parachor and

  7. Voltage Profile Improvement in Distribution System Using Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    V.Veera Nagireddy

    2016-06-01

    Full Text Available The traditional method in electric power distribution is to have centralized plants distributing electricity through an extensive distribution network. Distributed generation (DG provides electric power at a site closer to the customer which reduces the transmission and distribution costs, reduces fossil fuel emissions, capital cost, reduce maintenance costs and improve the distribution feeder voltage profiles. In the case of small generation systems, the locations of DG and penetration level of DG are usually not priori known. In this paper, Particle Swarm Optimization (PSO algorithm attempts to calculate the boundaries of the randomly placed distributed generators in a distribution network. simulations are performed using MATLAB, and overall better improvements are determined with estimated DG size and location. The proposed PSO approach is compared with conventional method on IEEE 34 bus distribution feeder network

  8. Improved wavelet neural network combined with particle swarm optimization algorithm and its application

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    An improved wavelet neural network algorithm which combines with particle swarm optimization was proposed to avoid encountering the curse of dimensionality and overcome the shortage in the responding speed and learning ability brought about by the traditional models. Based on the operational data provided by a regional power grid in the south of China, the method was used in the actual short term load forecasting. The results show that the average time cost of the proposed method in the experiment process is reduced by 12.2 s, and the precision of the proposed method is increased by 3.43% compared to the traditional wavelet network. Consequently, the improved wavelet neural network forecasting model is better than the traditional wavelet neural network forecasting model in both forecasting effect and network function.

  9. Optimization of top polymer gratings to improve GaN LEDs light transmission

    Institute of Scientific and Technical Information of China (English)

    Xiaomin Jin; Bei Zhang; Tao Dai; Wei Wei; Xiangning; Guoyi Zhang; Simeon Trieu; Fei Wang

    2008-01-01

    @@ We present a grating model of two-dimensional (2D) rigorous coupled wave analysis (RCWA) to study top diffraction gratings on light-emitting diodes(LEDs). We compare the integrated-transmission of the non-grating,rectangular-grating,and triangular-grating cases for the same grating period of 6μm,and show that the triangular grating has the best performance. For the triangular grating with 6-μmperiod, the LED achieves the highest light transmission at 6-μ gratingbottom width and 2.9-μm grating depth. Compared with the non-grating case, the optimized light transmission improvement is about 74.6%.The simulation agrees with the experimental data of the thin ploymer grating encapsulated flip-chip(FC) GaN-based LEDs for the light extraction improvement.

  10. DNA extraction of birch leaves by improved CTAB method and optimization of its ISSR system

    Institute of Scientific and Technical Information of China (English)

    PAN hua; YANG Chuan-ping; WEI Zhi-gang; JIANG Jing

    2006-01-01

    The basic method of DNA extraction (CTAB) was improved as the multi-times STE-CTAB extraction method and used to extract the DNA of birch leaved in this experiment. Results showed that the improved method is suitable not only for genomic DNA extraction of birch but also for that of other plants. The purity of genomic DNA extracted by the multi-times STE-CTAB extraction method is higher than that by one time STE-CTAB method, and it does not need the process of RNase. The factors of influencing ISSR system were explored based on the genomic DNA of birch extracted by the two methods. The optimal conditions for ISSR system were determined as follows: cycles of denaturation for 30 s at 94℃, annealing for 30 s at 51 ℃, extension for 30 s at 72℃, and a final 7 min extension at 72 ℃.

  11. Optimization of the Design of Pre-Signal System Using Improved Cellular Automaton

    Directory of Open Access Journals (Sweden)

    Yan Li

    2014-01-01

    Full Text Available The pre-signal system can improve the efficiency of intersection approach under rational design. One of the main obstacles in optimizing the design of pre-signal system is that driving behaviors in the sorting area cannot be well evaluated. The NaSch model was modified by considering slow probability, turning-deceleration rules, and lane changing rules. It was calibrated with field observed data to explore the interactions among design parameters. The simulation results of the proposed model indicate that the length of sorting area, traffic demand, signal timing, and lane allocation are the most important influence factors. The recommendations of these design parameters are demonstrated. The findings of this paper can be foundations for the design of pre-signal system and show promising improvement in traffic mobility.

  12. Optimization of the design of pre-signal system using improved cellular automaton.

    Science.gov (United States)

    Li, Yan; Li, Ke; Tao, Siran; Wan, Xia; Chen, Kuanmin

    2014-01-01

    The pre-signal system can improve the efficiency of intersection approach under rational design. One of the main obstacles in optimizing the design of pre-signal system is that driving behaviors in the sorting area cannot be well evaluated. The NaSch model was modified by considering slow probability, turning-deceleration rules, and lane changing rules. It was calibrated with field observed data to explore the interactions among design parameters. The simulation results of the proposed model indicate that the length of sorting area, traffic demand, signal timing, and lane allocation are the most important influence factors. The recommendations of these design parameters are demonstrated. The findings of this paper can be foundations for the design of pre-signal system and show promising improvement in traffic mobility.

  13. An Improved Control Vector Iteration Approach for Nonlinear Dynamic Optimization. II. Problems with Path Constraints

    Institute of Scientific and Technical Information of China (English)

    胡云卿; 刘兴高; 薛安克

    2014-01-01

    This paper considers dealing with path constraints in the framework of the improved control vector it-eration (CVI) approach. Two available ways for enforcing equality path constraints are presented, which can be di-rectly incorporated into the improved CVI approach. Inequality path constraints are much more difficult to deal with, even for small scale problems, because the time intervals where the inequality path constraints are active are unknown in advance. To overcome the challenge, the l1 penalty function and a novel smoothing technique are in-troduced, leading to a new effective approach. Moreover, on the basis of the relevant theorems, a numerical algo-rithm is proposed for nonlinear dynamic optimization problems with inequality path constraints. Results obtained from the classic batch reactor operation problem are in agreement with the literature reports, and the computational efficiency is also high.

  14. Optimizing hyaluronidase dose and plasmid DNA delivery greatly improves gene electrotransfer efficiency in rat skeletal muscle

    DEFF Research Database (Denmark)

    Åkerström, Thorbjörn; Vedel, Kenneth; Needham Andersen, Josefine;

    2015-01-01

    delivery across the muscle by increasing the number of plasmid DNA injections further enhanced transfection efficiency whereas increasing plasmid dose from 0.2 to 1.6. μg/g b.w. or vehicle volume had no effect. The optimized protocol resulted in ~80% (CI95%: 79-84%) transfected muscle fibers......Transfection of rat skeletal muscle in vivo is a widely used research model. However, gene electrotransfer protocols have been developed for mice and yield variable results in rats. We investigated whether changes in hyaluronidase pre-treatment and plasmid DNA delivery can improve transfection...... with a homogenous distribution. We also show that transfection was stable over five weeks of regular exercise or inactivity. Our findings show that species-specific plasmid DNA delivery and hyaluronidase pre-treatment greatly improves transfection efficiency in rat skeletal muscle....

  15. An Umeclidinium membrane sensor; Two-step optimization strategy for improved responses.

    Science.gov (United States)

    Yehia, Ali M; Monir, Hany H

    2017-09-01

    In the scientific context of membrane sensors and improved experimentation, we devised an experimentally designed protocol for sensor optimization. Two-step strategy was implemented for Umeclidinium bromide (UMEC) analysis which is a novel quinuclidine-based muscarinic antagonist used for maintenance treatment of symptoms accompanied with chronic obstructive pulmonary disease. In the first place, membrane components were screened for ideal ion exchanger, ionophore and plasticizer using three categorical factors at three levels in Taguchi design. Secondly, experimentally designed optimization was followed in order to tune the sensor up for finest responses. Twelve experiments were randomly carried out in a continuous factor design. Nernstian response, detection limit and selectivity were assigned as responses in these designs. The optimized membrane sensor contained tetrakis-[3,5-bis(trifluoro- methyl)phenyl] borate (0.44wt%) and calix[6]arene (0.43wt%) in 50.00% PVC plasticized with 49.13wt% 2-ni-tro-phenyl octylether. This sensor, along with an optimum concentration of inner filling solution (2×10(-4)molL(-1) UMEC) and 2h of soaking time, attained the design objectives. Nernstian response approached 59.7mV/decade and detection limit decreased by about two order of magnitude (8×10(-8)mol L(-1)) through this optimization protocol. The proposed sensor was validated for UMEC determination in its linear range (3.16×10(-7) -1×10(-3)mol L(-1)) and challenged for selective discrimination of other congeners and inorganic cations. Results of INCRUSE ELLIPTA(®) inhalation powder analyses obtained from the proposed sensor and manufacturer's UPLC were statistically compared. Moreover the proposed sensor was successfully used for the determination of UMEC in plasma samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. An Improved Technique for Speech Signal De-noising Based on Wavelet Threshold and Invasive Weed Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Ali Shaban

    2017-07-01

    Full Text Available Speech signals play a significant role in the area of digital signal processing. When these signals pass through air as a channel of propagation, it interacts with noise. Therefore, it needs removing noise from corrupted signal without altering it. De-noising is a compromise between the removal of the largest possible amount of noise and the preservation of signal integrity. To improve the performance of the speech which displays high power fluctuations, a new speech de-noising method based on Invasive Weed Optimization (IWO is proposed. In addition, a theoretical model is modified to estimate the value of threshold without any priority of knowledge. This is done by implementing the IWO algorithm for kurtosis measuring of the residual noise signal to find an optimum threshold value at which the kurtosis function is maximum. It has been observed that the proposed method appeared better performance than other methods at the same condition. Moreover, the results show that the proposed IWO algorithm offered a better mean square error(MSE than Particle Swarm Optimization Algorithm (PSO for both one and multilevel decomposition. For instance, IWO brought an improvement in MSE in the range of 0.01 compared with PSO for multilevel decomposition.

  17. A six-month longitudinal evaluation significantly improves accuracy of predicting incipient Alzheimer's disease in mild cognitive impairment.

    Science.gov (United States)

    Mubeen, Asim M; Asaei, Ali; Bachman, Alvin H; Sidtis, John J; Ardekani, Babak A

    2017-07-01

    Early prediction of incipient Alzheimer's disease (AD) dementia in individuals with mild cognitive impairment (MCI) is important for timely therapeutic intervention and identifying participants for clinical trials at greater risk of developing AD. Methods to predict incipient AD in MCI have mostly utilized cross-sectional data. Longitudinal data enables estimation of the rate of change of variables, which along with the variable levels have been shown to improve prediction power. While some efforts have already been made in this direction, all previous longitudinal studies have been based on observation periods longer than one year, hence limiting their practical utility. It remains to be seen if follow-up evaluations within shorter intervals can significantly improve the accuracy of prediction in this problem. Our aim was to determine the added value of incorporating 6-month longitudinal data for predicting progression from MCI to AD. Using 6-months longitudinal data from 247 participants with MCI, we trained two Random Forest classifiers to distinguish between progressive MCI (n=162) and stable MCI (n=85) cases. These models utilized structural MRI, neurocognitive assessments, and demographic information. The first model (cross-sectional) only used baseline data. The second model (longitudinal) used data from both baseline and a 6-month follow-up evaluation allowing the model to additionally incorporate biomarkers' rate of change. The longitudinal model (AUC=0.87; accuracy=80.2%) performed significantly better (P<0.05) than the cross-sectional model (AUC=0.82; accuracy=71.7%). Short-term longitudinal assessments significantly enhance the performance of AD prediction models. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  18. Improving the coherence properties of solid-state spin ensembles via optimized dynamical decoupling

    Science.gov (United States)

    Farfurnik, D.; Jarmola, A.; Pham, L. M.; Wang, Z. H.; Dobrovitski, V. V.; Walsworth, R. L.; Budker, D.; Bar-Gill, N.

    2016-04-01

    In this work, we optimize a dynamical decoupling (DD) protocol to improve the spin coherence properties of a dense ensemble of nitrogen-vacancy (NV) centers in diamond. Using liquid nitrogen-based cooling and DD microwave pulses, we increase the transverse coherence time T2 from ˜ 0.7 ms up to ˜ 30 ms. We extend previous work of single-axis (Carr-Purcell-Meiboom-Gill) DD towards the preservation of arbitrary spin states. After performing a detailed analysis of pulse and detuning errors, we compare the performance of various DD protocols. We identify that the concatenated XY8 pulse sequences serves as the optimal control scheme for preserving an arbitrary spin state. Finally, we use the concatenated sequences to demonstrate an immediate improvement of the AC magnetic sensitivity up to a factor of two at 250 kHz. For future work, similar protocols may be used to increase coherence times up to NV-NV interaction time scales, a major step toward the creation of quantum collective NV spin states.

  19. TO THE QUESTION OF IMPROVING THE QUALITY OF DISSERTATIONS AND OPTIMIZATION OF DISSERTATION COUNCILS

    Directory of Open Access Journals (Sweden)

    Grigorash O. V.

    2015-11-01

    Full Text Available It is known, that the development of fundamental and applied sciences, besides research institutes, are the universities. Integration of scientific researches of higher school into production occurs in many forms and can be largely determined by the quality of the training, including defense of thesis, research and teaching staff of the university. The article criticized the Ministry of education and science of the Russian Federation, and the higher attestation Commission of Russian Academy of Sciences aimed at improving the quality of work of dissertation councils and of the level of theses, based on the optimization of the network of dissertation councils, including their union, raising the level of members of dissertation councils. We have suggested a number of measures and specific requirements for the content of dissertations and supervisors of theses, official opponents of the thesis councils and their members, employees of the HAC. Introduction of considered proposals concerning increasing the level of theses into practice of work of dissertation councils, one set of measures will allow to optimize the network of dissertation councils and to improve the quality of their work

  20. Optimizing of Make Up Air Performance for Commercial Kitchen Ventilation Improvement

    Directory of Open Access Journals (Sweden)

    Manshoor B.

    2014-07-01

    Full Text Available A commercial kitchen is a complicated environment where multiple components of a ventilation system including kitchen hood, exhaust fan, air supply, and make up air systems work together but not always in unison. For the commercial kitchen environment, make up air systems used to control the kitchen space from unwanted odor and thermal confort. Make air systems for commercial kitchen already established. However, an optimization is important to determine the most suitable make air systems and at the same time can improve the thermal comfort in the working space. In this study, a simulation work was conducted to investigate a suitable supply air velocity to optimize the make up air for kitchen ventilation system. In order to achieve the objectives, ANSYS FLUENT software (CFD was used to carry out the simulation and analysis. 3D kitchen space with 10m x 8m x 3m with air supply velocity was set to 0 m/s, 0.14 m/s, 0.28 m/s and 0.42 m/s. From the simulation work, the velocity of air flow tested which is 0.28 m/s is enough to control the heat and give an enough comfort to the working space for the size of kitchen simulated. Well implementation of the make up air in the kitchen hood can improve an air quality in the commercial kitchen and also keep the kitchen space comfortable to the workers.

  1. [Performance optimization of property-improved biodiesel manufacturing process coupled with butanol extractive fermentation].

    Science.gov (United States)

    Zhang, Longyun; Yang, Ying; Shi, Zhongping

    2008-11-01

    The products concentrations in traditional acetone-butanol (AB) fermentation are too low that large amount of energy has to be consumed in the distillation and product recovery process. Aiming at direct utilization of the fermentation products, in this study, optimization of property-improved biodiesel manufacturing process coupled with AB extractive fermentation was conducted, under the condition of using the biodiesel originated from waste cooking oil as the extractant and high concentrated corn flour medium. The effect of biodiesel/broth volume ratio, waste supernatant recycle ratio, and electronic carrier addition on the major process performance index was carefully investigated. Under the optimized condition, the biodiesel quality was improved with the cetane value increased from 51.4 to 54.4; "actual butanol yield" reached to a level of 18%, and waste supernatant recycle ratio exceeded 50%. In this way, elimination of energy-consuming product recovery process and realization of "energy-saving & waste minimization" industrial production target advocated by the state government, could be potentially expected.

  2. Improving the simultaneous production of laccase and lignin peroxidase from Streptomyces lavendulae by medium optimization.

    Science.gov (United States)

    Jing, Debing

    2010-10-01

    To improve laccase (Lac) and lignin peroxidase (LiP) production from Streptomyces lavendulae, the Lac and LiP activity models were constructed and the C-N sources formulation in the medium optimal for the simultaneous production of Lac-LiP complex was asparagine 16.44%, urea 23.48%, fructose 18.01%, malt extract 21.21%, (NH(4))(2)SO(4) 20.86%. By nutritional analysis, the optimal initial mole ratio of C/N for laccase and LiP production were 1.48, 1.43 with C, N levels of 1.298-1.308 mol L(-1) and 0.875-0.912 mol L(-1), respectively. Verification experiment revealed that the initial C/N ratio in medium was the key factor affecting laccase activity, and the combined C, N sources could improve ligninolytic enzymes activity. Thus, enzyme production cost could be cut down effectively, not only by the simultaneous fermentation of Lac-LiP complex, but also by maintaining the initial C/N mole ratio at 1.43-1.48 in the medium with low levels, and different kinds of C and N sources. Copyright 2010 Elsevier Ltd. All rights reserved.

  3. End to End Delay Improvement in Heterogeneous Multicast Network using Genetic Optimization

    Directory of Open Access Journals (Sweden)

    V. Chandrasekar

    2012-01-01

    Full Text Available Problem statement: Multicast is a concept of group communication which refers to transmitting the same data or messages from a source to multiple destinations in the network. This one-to-many group communication is a generalization of the concepts of one-to-one unicast and one-to-all broadcast. To deliver data from the sender to all receivers efficiently, routing plays an important role in multicast communication. In QoS multicast, every receiver must receive the data within their own specified QoS constraints. This becomes challenging especially if the network is a heterogeneous network made up of wired and wireless devices. Approach: This study investigates the performance of Protocol Independent Multicast-Sparse Mode (PIM-SM protocol in a heterogeneous network running an video conferencing application and proposes an enhanced routing protocol using Genetic Optimizing techniques to improve QOS parameters in the wireless part. Results and Conclusion: Extensive simulations were carried out using the proposed technique and existing PIM-SM. The proposed optimization technique not only improves the throughput of the network but also decreased the end to end delay."

  4. Contextual Cueing Improves Attentional Guidance, Even When Guidance Is Supposedly Optimal.

    Science.gov (United States)

    Harris, Anthony M; Remington, Roger W

    2017-02-23

    Visual search through previously encountered contexts typically produces reduced reaction times compared with search through novel contexts. This contextual cueing benefit is well established, but there is debate regarding its underlying mechanisms. Eye-tracking studies have consistently shown reduced number of fixations with repetition, supporting improvements in attentional guidance as the source of contextual cueing. However, contextual cueing benefits have been shown in conditions in which attentional guidance should already be optimal-namely, when attention is captured to the target location by an abrupt onset, or under pop-out conditions. These results have been used to argue for a response-related account of contextual cueing. Here, we combine eye tracking with response time to examine the mechanisms behind contextual cueing in spatially cued and pop-out conditions. Three experiments find consistent response time benefits with repetition, which appear to be driven almost entirely by a reduction in number of fixations, supporting improved attentional guidance as the mechanism behind contextual cueing. No differences were observed in the time between fixating the target and responding-our proxy for response related processes. Furthermore, the correlation between contextual cueing magnitude and the reduction in number of fixations on repeated contexts approaches 1. These results argue strongly that attentional guidance is facilitated by familiar search contexts, even when guidance is near-optimal. (PsycINFO Database Record

  5. Multi-objective Optimization of Biochemical System Production Using an Improve Newton Competitive Differential Evolution Method

    Directory of Open Access Journals (Sweden)

    Mohd Arfian Ismail

    2017-09-01

    Full Text Available In this paper, an improve method of multi-objective optimization for biochemical system production is presented and discussed in detail. The optimization process of biochemical system production become hard and difficult when involved a large biochemical system that contain with many components. In addition, the multi-objective problem also need to be considered. Due to that, this study proposed and improve method that comprises with Newton method, differential evolution algorithm (DE and competitive co-evolutionary algorithm(ComCA. The aim of the proposed method is to maximize the production and simultaneously minimize the total amount of chemical concentrations involves. The operation of the proposed method starts with Newton method by dealing with biochemical system production as a nonlinear equations system. Then DE and ComCA are used to represent the variables in nonlinear equation system and tune the variables in order to find the best solution. The used of DE is to maximize the production while ComCA is to minimize the total amount of chemical concentrations involves. The effectiveness of the proposed method is evaluated using two benchmark biochemical systems and the experimental results show that the proposed method perform well compared to other works.

  6. Suction against resistance: a new breathing technique to significantly improve the blood flow ratio of the superior and inferior vena cava.

    Science.gov (United States)

    Gutzeit, Andreas; Roos, Justus E; Hergan, Klaus; von Weymarn, Constantin; Wälti, Stephan; Reischauer, Carolin; Froehlich, Johannes M

    2014-12-01

    Optimal contrast within the pulmonary artery is achieved by the maximum amount of contrast-enhanced blood flowing through the superior vena cava (SVC), while minimum amounts of non-contrasted blood should originate from the inferior vena cava (IVC). This study aims to clarify whether "suction against resistance" might optimise this ratio. Phase-contrast pulse sequences on a 1.5T MRI magnet were used for flow quantification (mean flow (mL/s), stroke volume (Vol) in the SVC and IVC in volunteers. Different breathing manoeuvers were analysed repeatedly: free breathing; inspiration; expiration; suction against resistance, and Valsalva. To standardise breathing commands, volunteers performed suction and Valsalva manoeuvers with an MR-compatible manometer. Suction against resistance was associated with a significant drop of the IVC/SVC flow quotient (1.63 [range 1.3-2.0] p  0.05). Suction against resistance caused a significant drop in the IVC/SVC quotient. Theoretically, this breathing manoeuver might significantly improve the enhancement characteristics of CT angiography. Suction provokes reduction in blood flow in the inferior vena cava. Ratio between the inferior and superior vena cava blood flow diminished during suction. Manometer used during breathing standardises MR phase-contrast blood flow measurements.

  7. Improved Persistent Scatterer analysis using Amplitude Dispersion Index optimization of dual polarimetry data

    Science.gov (United States)

    Esmaeili, Mostafa; Motagh, Mahdi

    2016-07-01

    Time-series analysis of Synthetic Aperture Radar (SAR) data using the two techniques of Small BAseline Subset (SBAS) and Persistent Scatterer Interferometric SAR (PSInSAR) extends the capability of conventional interferometry technique for deformation monitoring and mitigating many of its limitations. Using dual/quad polarized data provides us with an additional source of information to improve further the capability of InSAR time-series analysis. In this paper we use dual-polarized data and combine the Amplitude Dispersion Index (ADI) optimization of pixels with phase stability criterion for PSInSAR analysis. ADI optimization is performed by using Simulated Annealing algorithm to increase the number of Persistent Scatterer Candidate (PSC). The phase stability of PSCs is then measured using their temporal coherence to select the final sets of pixels for deformation analysis. We evaluate the method for a dataset comprising of 17 dual polarization SAR data (HH/VV) acquired by TerraSAR-X data from July 2013 to January 2014 over a subsidence area in Iran and compare the effectiveness of the method for both agricultural and urban regions. The results reveal that using optimum scattering mechanism decreases the ADI values in urban and non-urban regions. As compared to single-pol data the use of optimized polarization increases initially the number of PSCs by about three times and improves the final PS density by about 50%, in particular in regions with high rate of deformation which suffer from losing phase stability over the time. The classification of PS pixels based on their optimum scattering mechanism revealed that the dominant scattering mechanism of the PS pixels in the urban area is double-bounce while for the non-urban regions (ground surfaces and farmlands) it is mostly single-bounce mechanism.

  8. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis.

    Science.gov (United States)

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-19

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants.

  9. Active surface model improvement by energy function optimization for 3D segmentation.

    Science.gov (United States)

    Azimifar, Zohreh; Mohaddesi, Mahsa

    2015-04-01

    This paper proposes an optimized and efficient active surface model by improving the energy functions, searching method, neighborhood definition and resampling criterion. Extracting an accurate surface of the desired object from a number of 3D images using active surface and deformable models plays an important role in computer vision especially medical image processing. Different powerful segmentation algorithms have been suggested to address the limitations associated with the model initialization, poor convergence to surface concavities and slow convergence rate. This paper proposes a method to improve one of the strongest and recent segmentation algorithms, namely the Decoupled Active Surface (DAS) method. We consider a gradient of wavelet edge extracted image and local phase coherence as external energy to extract more information from images and we use curvature integral as internal energy to focus on high curvature region extraction. Similarly, we use resampling of points and a line search for point selection to improve the accuracy of the algorithm. We further employ an estimation of the desired object as an initialization for the active surface model. A number of tests and experiments have been done and the results show the improvements with regards to the extracted surface accuracy and computational time of the presented algorithm compared with the best and recent active surface models.

  10. Numerical optimization of flow uniformity inside an under body- oval substrate to improve emissions of IC engines

    Directory of Open Access Journals (Sweden)

    Om Ariara Guhan C.P.

    2016-07-01

    Full Text Available Oval substrates are widely used in automobiles to reduce the exhaust emissions in Diesel oxidation Catalyst of CI engine. Because of constraints in space and packaging Oval substrate is preferred rather than round substrate. Obtaining the flow uniformity is very challenging in oval substrate comparing with round substrate. In this present work attempts are made to optimize the inlet cone design to achieve the optimal flow uniformity with the help of CATIA V5 which is 3D design tool and CFX which is 3D CFD tool. Initially length of inlet cone and mass flow rate of exhaust stream are analysed to understand the effects of flow uniformity and pressure drop. Then short straight cones and angled cones are designed. Angled cones have been designed by two methodologies. First methodology is rotating flow inlet plane along the substrate in shorter or longer axis. Second method is shifting the flow inlet plane along the longer axis. Large improvement in flow uniformity is observed when the flow inlet plane is shifted along the direction of longer axis by 10, 20 and 30 mm away from geometrical centre. When the inlet plane is rotated again based on 30 mm shifted geometry, significant improvement at rotation angle of 20° is observed. The flow uniformity is optimum when second shift is performed based on second rotation. This present work shows that for an oval substrate flow, uniformity index can be optimized when inlet cone is angled by rotation of flow inlet plane along axis of substrate.

  11. Optimization of FS Welding Parameters for Improving Mechanical Behavior of AA2024-T351 Joints Based on Taguchi Method

    Science.gov (United States)

    Vidal, C.; Infante, V.

    2013-08-01

    In the present study, the design of an experiment technique, the Taguchi method, has been used to optimize the friction stir welding (FSW) parameters for improving mechanical behavior of AA2024-T351 joints. The parameters considered were vertical downward forging force, tool travel speed, and probe length. An orthogonal array of L9 (34) was used; ANOVA analyses were carried out to identify the significant factors affecting tensile strength (Global Efficiency to Tensile Strength—GETS), bending strength (Global Efficiency to Bending—GEB), and hardness field. The percentage contribution of each parameter was also determined. As a result of the Taguchi analysis in this study, the probe length is the most significant parameter on GETS, and the tool travel speed is the most important parameter affecting both the GEB and the hardness field. An algebraic model for predicting the best mechanical performance, namely fatigue resistance, was developed and the optimal FSW combination was determined using this model. The results obtained were validated by conducting confirmation tests, the results of which verify the adequacy and effectiveness of this approach.

  12. New method of optimizing writing parameters in electron beam lithography systems for throughput improvement considering patterning fidelity constraints

    Science.gov (United States)

    Ng, Hoi-Tou; Shen, Yu-Tian; Chen, Sheng-Yung; Liu, Chun-Hung; Ng, Philip C. W.; Tsai, Kuen-Yu

    2012-07-01

    Low-energy electron beam lithography is one of the promising next-generation lithography technology solutions for the 21-nm half-pitch node and beyond because of fewer proximity effects, higher resist sensitivity, and less substrate damage compared with high-energy electron beam lithography. To achieve high-throughput manufacturing, low-energy electron beam lithography systems with writing parameters of larger beam size, larger grid size, and lower dosage are preferred. However, electron shot noise can significantly increase critical dimension deviation and line edge roughness. Its influence on patterning prediction accuracy becomes nonnegligible. To effectively maximize throughput while meeting patterning fidelity requirements according to the International Technology Roadmap for Semiconductors, a new method is proposed in this work that utilizes a new patterning prediction algorithm to rigorously characterize the patterning variability caused by the shot noise and a mathematical optimization algorithm to determine optimal writing parameters. The new patterning prediction algorithm can achieve a proper trade-off between computational effort and patterning prediction accuracy. Effectiveness of the new method is demonstrated on a static random-access memory circuit. The corresponding electrical performance is analyzed by using a gate-slicing technique and publicly available transistor models. Numerical results show that a significant improvement in the static noise margin can be achieved.

  13. Significant improvement of thermal stability for CeZrPrNd oxides simply by supercritical CO(2 drying.

    Directory of Open Access Journals (Sweden)

    Yunzhao Fan

    Full Text Available Pr and Nd co-doped Ce-Zr oxide solid solutions (CZPN were prepared using co-precipitation and microemulsion methods. It is found that only using supercritical CO(2 drying can result in a significant improvement of specific surface area and oxygen storage capacity at lower temperatures for CZPN after aging at 1000°C for 12 h in comparison with those using conventional air drying and even supercritical ethanol drying. Furthermore, the cubic structure was obtained in spite of the fact that the atomic ratio of Ce/(Ce+Zr+Pr+Nd is as low as 29%. The high thermal stability can be attributed to the loosely aggregated morphology and the resultant Ce enrichment on the nanoparticle surface, which are caused by supercritical CO(2 drying due to the elimination of surface tension effects on the gas-liquid interface.

  14. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    Science.gov (United States)

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system.

  15. Zero valent iron significantly enhances methane production from waste activated sludge by improving biochemical methane potential rather than hydrolysis rate.

    Science.gov (United States)

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-05

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system.

  16. Immunosuppression using the mammalian target of rapamycin (mTOR) inhibitor everolimus: pilot study shows significant cognitive and affective improvement.

    Science.gov (United States)

    Lang, U E; Heger, J; Willbring, M; Domula, M; Matschke, K; Tugtekin, S M

    2009-12-01

    Immunosuppression using calcineurin inhibitors (CNIs) is accompanied by neuropsychiatric side effects, which counteract longevity and quality of life benefits in 10% to 28% of patients. Following the availability of the mammalian target of rapamycin (mTOR) inhibitors, it became possible to replace CNI without increasing the risk of acute graft rejection. mTOR, a member of the phosphatidyl inositol 3' kinase family, is a downstream target of brain-derived neurotrophic factor, which has been implicated in the pathophysiology and treatment of several psychiatric disorders. Preclinical evidence has implicated the mTOR pathway in synaptic plasticity and fear memory consolidation and reconsolidation. In the present study we prospectively evaluated the psychiatric outcomes of CNI-free immunosuppression in adult maintenance heart transplant recipients (n = 9; age: 66.1 +/- 6.1) using the Wechsler Memory Scale-Revised (WMS-R), Symptom Checklist-90-Revised (SCL-90-R), Beck Depression Inventory (BDI), Trail Making Tests A and B, Digit Span (DS), and Hamilton Depression Scale (HAMD). Four weeks after switching to CNI-free immunosuppression using everolimus, BDI (Z = -1.14; P = .048), Trail Making tests A and B (Z = -2.52; P = .012), WMS-R (Z = 2.37; P = .018), and SCL-90-R (Z = -2.37; P = .018) were all significantly improved while DS (Z = -1.18; P = .236) and HAMD (Z = -0.595; P = .552) remained unchanged. This report describes favorable psychiatric outcome variables using everolimus in maintenance heart transplant recipients. CNI-free immunosuppression with everolimus might provide significant improvement in memory, concentration, and overall psychiatric symptoms among heart transplant recipients.

  17. An improved self-adaptive membrane computing optimization algorithm and its applications in residue hydrogenating model parameter estimation

    Institute of Scientific and Technical Information of China (English)

    芦会彬; 薄翠梅; 杨世品

    2015-01-01

    In order to solve the non-linear and high-dimensional optimization problems more effectively, an improved self-adaptive membrane computing (ISMC) optimization algorithm was proposed. The proposed ISMC algorithm applied improved self-adaptive crossover and mutation formulae that can provide appropriate crossover operator and mutation operator based on different functions of the objects and the number of iterations. The performance of ISMC was tested by the benchmark functions. The simulation results for residue hydrogenating kinetics model parameter estimation show that the proposed method is superior to the traditional intelligent algorithms in terms of convergence accuracy and stability in solving the complex parameter optimization problems.

  18. Land Surface Model and Particle Swarm Optimization Algorithm Based on the Model-Optimization Method for Improving Soil Moisture Simulation in a Semi-Arid Region.

    Directory of Open Access Journals (Sweden)

    Qidong Yang

    Full Text Available Improving the capability of land-surface process models to simulate soil moisture assists in better understanding the atmosphere-land interaction. In semi-arid regions, due to limited near-surface observational data and large errors in large-scale parameters obtained by the remote sensing method, there exist uncertainties in land surface parameters, which can cause large offsets between the simulated results of land-surface process models and the observational data for the soil moisture. In this study, observational data from the Semi-Arid Climate Observatory and Laboratory (SACOL station in the semi-arid loess plateau of China were divided into three datasets: summer, autumn, and summer-autumn. By combing the particle swarm optimization (PSO algorithm and the land-surface process model SHAW (Simultaneous Heat and Water, the soil and vegetation parameters that are related to the soil moisture but difficult to obtain by observations are optimized using three datasets. On this basis, the SHAW model was run with the optimized parameters to simulate the characteristics of the land-surface process in the semi-arid loess plateau. Simultaneously, the default SHAW model was run with the same atmospheric forcing as a comparison test. Simulation results revealed the following: parameters optimized by the particle swarm optimization algorithm in all simulation tests improved simulations of the soil moisture and latent heat flux; differences between simulated results and observational data are clearly reduced, but simulation tests involving the adoption of optimized parameters cannot simultaneously improve the simulation results for the net radiation, sensible heat flux, and soil temperature. Optimized soil and vegetation parameters based on different datasets have the same order of magnitude but are not identical; soil parameters only vary to a small degree, but the variation range of vegetation parameters is large.

  19. Looking ahead to significant improvements in mining safety and health through innovative research and effective diffusion into the industry

    Institute of Scientific and Technical Information of China (English)

    Jeffery L. Kohler

    2015-01-01

    Mining safety and health improvements over the past decades are remarkable by many metrics, and yet the expectation of society, and the goal of the mining industry, is zero harm. If we examine the underlying enablers for the significant gains that have been achieved, the key role that research to help understand the causes of problems and to develop lasting solutions is clear. Many of the remaining challenges have been resistant to solutions by various approaches. Some, such as fatalities and injuries from ground con-trol or powered haulage are prominent year after year. Different approaches are indicated and new solu-tions will be required if we are to achieve a goal of zero harm. These will originate with research, but into which topics, and what are some of these different approaches? This paper examines the current state of mine safety in the United States and highlights areas of significant opportunity for research that will lead to solutions. The likely direction of research that will enable realization of the ‘zero harm’ goal is described in terms of evolutionary and revolutionary approaches. Both are important, but the author’s view is that some of the largest gains will be made with trans-disciplinary approaches that break from the past. Topical areas of research are suggested and several research questions are given to illustrate the direction of future research in mining safety and health.

  20. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis

    Science.gov (United States)

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-01

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants.Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic

  1. Tunneled catheters with taurolidine-citrate-heparin lock solution significantly improve the inflammatory profile of hemodialysis patients.

    Science.gov (United States)

    Fontseré, Néstor; Cardozo, Celia; Donate, Javier; Soriano, Alex; Muros, Mercedes; Pons, Mercedes; Mensa, Josep; Campistol, Josep M; Navarro-González, Juan F; Maduell, Francisco

    2014-07-01

    Mortality and morbidity are significantly higher among patients with dialysis catheters, which has been associated with chronic activation of the immune system. We hypothesized that bacteria colonizing the catheter lumen trigger an inflammatory response. We aimed to evaluate the inflammatory profile of hemodialysis patients before and after locking catheters with an antimicrobial lock solution. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were measured in serum, and levels of mRNA gene expression of IL-6, IL-10, and TNF-α were analyzed in peripheral blood mononuclear cells (PBMC). Samples were obtained at baseline and again after 3 months' use of taurolidine-citrate-heparin lock solution (TCHLS) in 31 hemodialysis patients. The rate of catheter-related bloodstream infections (CRBSI) was 1.08 per 1,000 catheter-days in the heparin period and 0.04 in the TCHLS period (P = 0.023). Compared with the baseline data, serum levels of hs-CRP and IL-6 showed median percent reductions of 18.1% and 25.2%, respectively (P < 0.01), without significant changes in TNF-α or IL-10 levels. Regarding cytokine gene expression in PBMC, the median mRNA expression levels of TNF-α and IL-6 decreased by 20% (P < 0.05) and 19.7% (P = 0.01), respectively, without changes in IL-10 expression levels. The use of TCHLS to maintain the catheter lumen sterility significantly reduces the incidence of CRBSI and improves the inflammatory profile in hemodialysis patients with tunneled catheters. Further studies are needed to evaluate the potential beneficial effects on clinical outcomes.

  2. Optimized Policies for Improving Fairness of Location-based Relay Selection

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Olsen, Rasmus Løvenstein; Madsen, Tatiana Kozlova

    2013-01-01

    For WLAN systems in which relaying is used to improve throughput performance for nodes located at the cell edge, node mobility and information collection delays can have a significant impact on the performance of a relay selection scheme. In this paper we extend our existing Markov Chain modeling...

  3. Improved object optimal synthetic description, modeling, learning, and discrimination by GEOGINE computational kernel

    Science.gov (United States)

    Fiorini, Rodolfo A.; Dacquino, Gianfranco

    2005-03-01

    GEOGINE (GEOmetrical enGINE), a state-of-the-art OMG (Ontological Model Generator) based on n-D Tensor Invariants for n-Dimensional shape/texture optimal synthetic representation, description and learning, was presented in previous conferences elsewhere recently. Improved computational algorithms based on the computational invariant theory of finite groups in Euclidean space and a demo application is presented. Progressive model automatic generation is discussed. GEOGINE can be used as an efficient computational kernel for fast reliable application development and delivery in advanced biomedical engineering, biometric, intelligent computing, target recognition, content image retrieval, data mining technological areas mainly. Ontology can be regarded as a logical theory accounting for the intended meaning of a formal dictionary, i.e., its ontological commitment to a particular conceptualization of the world object. According to this approach, "n-D Tensor Calculus" can be considered a "Formal Language" to reliably compute optimized "n-Dimensional Tensor Invariants" as specific object "invariant parameter and attribute words" for automated n-Dimensional shape/texture optimal synthetic object description by incremental model generation. The class of those "invariant parameter and attribute words" can be thought as a specific "Formal Vocabulary" learned from a "Generalized Formal Dictionary" of the "Computational Tensor Invariants" language. Even object chromatic attributes can be effectively and reliably computed from object geometric parameters into robust colour shape invariant characteristics. As a matter of fact, any highly sophisticated application needing effective, robust object geometric/colour invariant attribute capture and parameterization features, for reliable automated object learning and discrimination can deeply benefit from GEOGINE progressive automated model generation computational kernel performance. Main operational advantages over previous

  4. Analysis and Improvement of the Energy Management of an Isolated Microgrid in Lencois Island based on a Linear Optimization Approach

    DEFF Research Database (Denmark)

    Federico, de Bosio; Hernández, Adriana Carolina Luna; de Sousa Ribeiro, Luiz Antonio;

    2016-01-01

    This paper proposes an optimization-based decision support strategy to enhance the management of the distributed energy sources of an islanded microgrid. The solutions provided by the optimization algorithm are compared with the current strategy, already implemented in a real site microgrid...... on Lencois’ island/Brazil. Significant economic and energy savings are achieved when the optimal management of the diesel generator is performed....

  5. Rapid Process Optimization: A Novel Process Improvement Methodology to Innovate Health Care Delivery.

    Science.gov (United States)

    Wiler, Jennifer L; Bookman, Kelly; Birznieks, Derek B; Leeret, Robert; Koehler, April; Planck, Shauna; Zane, Richard

    2016-03-26

    Health care systems have utilized various process redesign methodologies to improve care delivery. This article describes the creation of a novel process improvement methodology, Rapid Process Optimization (RPO). This system was used to redesign emergency care delivery within a large academic health care system, which resulted in a decrease: (1) door-to-physician time (Department A: 54 minutes pre vs 12 minutes 1 year post; Department B: 20 minutes pre vs 8 minutes 3 months post), (2) overall length of stay (Department A: 228 vs 184; Department B: 202 vs 192), (3) discharge length of stay (Department A: 216 vs 140; Department B: 179 vs 169), and (4) left without being seen rates (Department A: 5.5% vs 0.0%; Department B: 4.1% vs 0.5%) despite a 47% increased census at Department A (34 391 vs 50 691) and a 4% increase at Department B (8404 vs 8753). The novel RPO process improvement methodology can inform and guide successful care redesign.

  6. Approaches to Optimizing Animal Cell Culture Process: Substrate Metabolism Regulation and Protein Expression Improvement

    Science.gov (United States)

    Zhang, Yuanxing

    Some high value proteins and vaccines for medical and veterinary applications by animal cell culture have an increasing market in China. In order to meet the demands of large-scale productions of proteins and vaccines, animal cell culture technology has been widely developed. In general, an animal cell culture process can be divided into two stages in a batch culture. In cell growth stage a high specific growth rate is expected to achieve a high cell density. In production stage a high specific production rate is stressed for the expression and secretion of qualified protein or replication of virus. It is always critical to maintain high cell viability in fed-batch and perfusion cultures. More concern has been focused on two points by the researchers in China. First, the cell metabolism of substrates is analyzed and the accumulation of toxic by-products is decreased through regulating cell metabolism in the culture process. Second, some important factors effecting protein expression are understood at the molecular level and the production ability of protein is improved. In pace with the rapid development of large-scale cell culture for the production of vaccines, antibodies and other recombinant proteins in China, the medium design and process optimization based on cell metabolism regulation and protein expression improvement will play an important role. The chapter outlines the main advances in metabolic regulation of cell and expression improvement of protein in animal cell culture in recent years.

  7. Optimizing Bus Passenger Complaint Service through Big Data Analysis: Systematized Analysis for Improved Public Sector Management

    Directory of Open Access Journals (Sweden)

    Weng-Kun Liu

    2016-12-01

    Full Text Available With the advances in industry and commerce, passengers have become more accepting of environmental sustainability issues; thus, more people now choose to travel by bus. Government administration constitutes an important part of bus transportation services as the government gives the right-of-way to transportation companies allowing them to provide services. When these services are of poor quality, passengers may lodge complaints. The increase in consumer awareness and developments in wireless communication technologies have made it possible for passengers to easily and immediately submit complaints about transportation companies to government institutions, which has brought drastic changes to the supply–demand chain comprised of the public sector, transportation companies, and passengers. This study proposed the use of big data analysis technology including systematized case assignment and data visualization to improve management processes in the public sector and optimize customer complaint services. Taichung City, Taiwan, was selected as the research area. There, the customer complaint management process in public sector was improved, effectively solving such issues as station-skipping, allowing the public sector to fully grasp the service level of transportation companies, improving the sustainability of bus operations, and supporting the sustainable development of the public sector–transportation company–passenger supply chain.

  8. Approaches to optimizing animal cell culture process: substrate metabolism regulation and protein expression improvement.

    Science.gov (United States)

    Zhang, Yuanxing

    2009-01-01

    Some high value proteins and vaccines for medical and veterinary applications by animal cell culture have an increasing market in China. In order to meet the demands of large-scale productions of proteins and vaccines, animal cell culture technology has been widely developed. In general, an animal cell culture process can be divided into two stages in a batch culture. In cell growth stage a high specific growth rate is expected to achieve a high cell density. In production stage a high specific production rate is stressed for the expression and secretion of qualified protein or replication of virus. It is always critical to maintain high cell viability in fed-batch and perfusion cultures. More concern has been focused on two points by the researchers in China. First, the cell metabolism of substrates is analyzed and the accumulation of toxic by-products is decreased through regulating cell metabolism in the culture process. Second, some important factors effecting protein expression are understood at the molecular level and the production ability of protein is improved. In pace with the rapid development of large-scale cell culture for the production of vaccines, antibodies and other recombinant proteins in China, the medium design and process optimization based on cell metabolism regulation and protein expression improvement will play an important role. The chapter outlines the main advances in metabolic regulation of cell and expression improvement of protein in animal cell culture in recent years.

  9. Application of Fuzzy Sets for the Improvement of Routing Optimization Heuristic Algorithms

    Directory of Open Access Journals (Sweden)

    Mattas Konstantinos

    2016-12-01

    Full Text Available The determination of the optimal circular path has become widely known for its difficulty in producing a solution and for the numerous applications in the scope of organization and management of passenger and freight transport. It is a mathematical combinatorial optimization problem for which several deterministic and heuristic models have been developed in recent years, applicable to route organization issues, passenger and freight transport, storage and distribution of goods, waste collection, supply and control of terminals, as well as human resource management. Scope of the present paper is the development, with the use of fuzzy sets, of a practical, comprehensible and speedy heuristic algorithm for the improvement of the ability of the classical deterministic algorithms to identify optimum, symmetrical or non-symmetrical, circular route. The proposed fuzzy heuristic algorithm is compared to the corresponding deterministic ones, with regard to the deviation of the proposed solution from the best known solution and the complexity of the calculations needed to obtain this solution. It is shown that the use of fuzzy sets reduced up to 35% the deviation of the solution identified by the classical deterministic algorithms from the best known solution.

  10. Improved free-surface expression for frequency-domain elastic optimal mixed-grid modeling

    Science.gov (United States)

    Cao, Jian; Chen, Jing-Bo; Dai, Meng-Xue

    2016-07-01

    An accurate and efficient forward modeling is the foundation of full-waveform inversion (FWI). In elastic wave modeling, one of the key problems is how to deal with the free-surface boundary condition appropriately. For the representation of the free-surface boundary condition, conventional displacement-based approaches and staggered-grid approaches are often used in time-domain. In frequency-domain, considering the saving of storage and CPU time, we integrate the idea of physical parameter-modified staggered-grid approach in time-domain with an elastic optimal mixed-grid modeling scheme to design an improved parameter-modified free-surface expression. Accuracy analysis shows that an elastic optimal mixed-grid modeling scheme using the parameter-modified free-surface expression can provide more accurate solutions with only 4 grid points per smallest shear wavelength than conventional displacement-based approaches and is stable for most Poisson ratios. Besides, it also yields smaller condition number of the resulting impedance matrix than conventional displacement-based approaches in laterally varying complex media. These advantages reveal great potential of this free-surface expression in big-data practical application.

  11. An Improved Self-adaptive Control Parameter of Differential Evolution for Global Optimization

    Science.gov (United States)

    Jia, Liyuan; Gong, Wenyin; Wu, Hongbin

    Differential evolution (DE), a fast and robust evolutionary algorithm for global optimization, has been widely used in many areas. However, the success of DE for solving different problems mainly depends on properly choosing the control parameter values. On the other hand, DE is good at exploring the search space and locating the region of global minimum, but it is slow at exploiting the solution. In order to alleviate these drawbacks of DE, this paper proposes an improved self-adaptive control parameter of DE, referred to as ISADE, for global numerical optimization. The proposed approach employs the individual fitness information to adapt the parameter settings. Hence, it can exploit the information of the individual and generate the promising offspring efficiently. To verify the viability of the proposed ISADE, 10 high-dimensional benchmark problems are chosen from literature. Experiment results indicate that this approach is efficient and effective. It is proved that this approach performs better than the original DE in terms of the convergence rate and the quality of the final solutions. Moreover, ISADE obtains faster convergence than the original self-adaptive control parameter of DE (SADE).

  12. Improved Iterative Calibration for Triaxial Accelerometers Based on the Optimal Observation

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2012-06-01

    Full Text Available This paper presents an improved iterative nonlinear calibration method in the gravitational field for both low-grade and high-grade triaxial accelerometers. This calibration method assumes the probability density function of a Gaussian distribution for the raw outputs of triaxial accelerometers. A nonlinear criterion function is derived as the maximum likelihood estimation for the calibration parameters and inclination vectors, which is solved by the iterative estimation. First, the calibration parameters, including the scale factors, misalignments, biases and squared coefficients are estimated by the linear least squares method according to the multi-position raw outputs of triaxial accelerometers and the initial inclination vectors. Second, the sequence quadric program method is utilized to solve the nonlinear constrained optimization to update the inclination vectors according to the estimated calibration parameters and raw outputs of the triaxial accelerometers. The initial inclination vectors are supplied by normalizing raw outputs of triaxial accelerometers at different positions without any a priori knowledge. To overcome the imperfections of models, the optimal observation scheme is designed according to some maximum sensitivity principle. Simulation and experiments show good estimation accuracy for calibration parameters and inclination vectors.

  13. Evaluation of Optimal Pore Size of (3-Aminopropyltriethoxysilane Grafted MCM-41 for Improved CO2 Adsorption

    Directory of Open Access Journals (Sweden)

    Zhilin Liu

    2015-01-01

    Full Text Available An array of new MCM-41 with substantially larger average pore diameters was synthesized through adding 1,3,5-trimethylbenzene (TMB as the swelling agent to explore the effect of pore size on final adsorbent properties. The pore expanded MCM-41 was also grafted with (3-Aminopropyltriethoxysilane (APTES to determine the optimal pore size for CO2 adsorption. The pore-expanded mesoporous MCM-41s showed relatively less structural regularity but significant increments of pore diameter (4.64 to 7.50 nm; the fraction of mesopore volume also illustrated an increase. The adsorption heat values were correlated with the order of the adsorption capacities for pore expanded MCM-41s. After amine functionalization, the adsorption capacities and heat values showed a significant increase. APTES-grafted pore-expanded MCM-41s depicted a high potential for CO2 capture regardless of the major drawback of the high energy required for regeneration.

  14. Improved heterologous gene expression in Trichoderma reesei by cellobiohydrolase I gene (cbh1) promoter optimization

    Institute of Scientific and Technical Information of China (English)

    Ti Liu; Tianhong Wang; Xian Li; Xuan Liu

    2008-01-01

    To improve heterologous gene expression in Trichoderma reesei, a set of optimal artificial cellobiohydrolase I gene (cbh1) promoters was obtained. The region from-677 to -724 with three potential glucose repressor binding sites was deleted. Then the region from-620 to-820 of the modified cbh1 promoter, including the CCAAT box and the Ace2 binding site, was repeatedly inserted into the modified cbh1 promoter, obtaining promoters with copy numbers 2, 4,and 6. The results showed that the glucose repression effects were abolished and the expression level of the glucuronidase (gus) reporter gene regulated by these multi-copy promoters was markedly enhanced as the copy number increased simultaneously. The data showed the great promise of using the promoter artificial modification strategy to increase heterologous gene expression in filamentous fungi and provided a set of optional high-expression vectors for gene function investigation and strain modification.

  15. Optimal Conductor Selection in Radial Distribution Systems for Productivity Improvement Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Mahdi Mozaffari Legha

    2013-06-01

    Full Text Available Development of distribution systems result in higher system losses and poor voltage regulation. Consequently, an efficient and effective distribution system has become more urgent and important. Hence proper selection of conductors in the distribution system is important as it determines the current density and the resistance of the line. This paper examines the use of different evolutionary algorithms, genetic algorithm (GA, to optimal branch conductor selection in planning radial distribution systems with the objective to minimize the overall cost of annual energy losses and depreciation on the cost of conductors and reliability in order to improve productivity. Furthermore, The Backward-Forward sweep iterative method was adopted to solve the radial load flow analysis. Simulations are carried out on 69-bus radial distribution network using GA approach in order to show the accuracy as well as the efficiency of the proposed solution technique.

  16. Improving the energy balance of grass-based anaerobic digestion through harvesting optimization

    DEFF Research Database (Denmark)

    Tsapekos, Panagiotis; Kougias, Panagiotis; Egelund, H.

    to determine the treatment with the best energy balance, the energy demand during harvesting was compared to the practical methane yield. The biomethanation process was evaluated using triplicate batch assays under thermophilic conditions following the guidelines of the biochemical methane potential (BMP...... that the appropriate harvester can improve the energy output by approximately 2.4 GJ/ha under optimal conditions and subsequently, the overall sustainability of grass-based AD....... efficiency is still doubted and thus, they are not widely used in full-scale biogas plants. In addition, these methods are typically associated with increased costs or energy demands. Hence, there is a need to find effective and cost-efficient solutions that boost biomass decomposition. In this concept, one...

  17. Postoperative pain management in children has been improved, but can be further optimized

    DEFF Research Database (Denmark)

    Kart, T; van der Laan, K; Crombach, J

    1996-01-01

    and movement and incidence and severity of side effects were measured four times postoperatively. Fifty-nine children aged 3 to 15 years undergoing miscellaneous operations participated. All children received analgesic treatment. During the study period 26 children reported at least one episode of unacceptable...... pain, while unacceptable pruritus, nausea or vomiting were observed in 18 children. It was not possible to relate the incidence of pain and side effects to any particular analgesic treatment or type of surgery, but groups of children that might need additional attention were identified. Even though...... improvements have been obtained, it is still a challenge to optimize the postoperative pain management of children, and when doing so attention should be paid not only to pain relief, but also to side effects of the administered analgesics....

  18. Improved optimal steering law for SGCMG and adaptive attitude control of flexible spacecraft

    Institute of Scientific and Technical Information of China (English)

    Lu Wang; Yu Guo; Liping Wu; Qingwei Chen

    2015-01-01

    The issue of attitude maneuver of a flexible spacecraft is investigated with single gimbaled control moment gyroscopes (SGCMGs) as an actuator. To solve the inertia uncertainty of the system, an adaptive attitude control algorithm is designed by ap-plying a radial basis function (RBF) neural network. An improved steering law for SGCMGs is proposed to achieve the optimal out-put torque. It enables the SGCMGs not only to avoid singularity, but also to output more precise torque. In addition, global, uniform, ultimate bounded stability of the attitude control system is proved via the Lyapunov technique. Simulation results demonstrate the effectiveness of the new steering law and the algorithm of attitude maneuver of the flexible spacecraft.

  19. Optimizing hyaluronidase dose and plasmid DNA delivery greatly improves gene electrotransfer efficiency in rat skeletal muscle

    DEFF Research Database (Denmark)

    Åkerström, Thorbjörn; Vedel, Kenneth; Needham Andersen, Josefine

    2015-01-01

    Transfection of rat skeletal muscle in vivo is a widely used research model. However, gene electrotransfer protocols have been developed for mice and yield variable results in rats. We investigated whether changes in hyaluronidase pre-treatment and plasmid DNA delivery can improve transfection...... efficiency in rat skeletal muscle. We found that pre-treating the muscle with a hyaluronidase dose suitable for rats (0.56. U/g b.w.) prior to plasmid DNA injection increased transfection efficiency by >200% whereas timing of the pre-treatment did not affect efficiency. Uniformly distributing plasmid DNA...... delivery across the muscle by increasing the number of plasmid DNA injections further enhanced transfection efficiency whereas increasing plasmid dose from 0.2 to 1.6. μg/g b.w. or vehicle volume had no effect. The optimized protocol resulted in ~80% (CI95%: 79-84%) transfected muscle fibers...

  20. Design and optimization of a novel organic Rankine cycle with improved boiling process

    DEFF Research Database (Denmark)

    Andreasen, Jesper Graa; Larsen, U.; Knudsen, Thomas

    2015-01-01

    In this paper we present a novel organic Rankine cycle layout, named the organic split-cycle, designed for utilization of low grade heat. The cycle is developed by implementing a simplified version of the split evaporation concept from the Kalina split-cycle in the organic Rankine cycle in order....../pentane mixture which, for the 90 °C hot fluid inlet temperature case, achieves a 14.5% higher net power output than an optimized organic Rankine cycle using the same mixture. Two parameter studies suggest that optimum conditions for the organic split-cycle are when the temperature profile allows the minimum...... pinch point temperature difference to be reached at two locations in the boiler. Compared to the transcritical organic Rankine cycle, the organic split-cycle improves the boiling process without an entailing increase in the boiler pressure, thus enabling an efficient low grade heat to power conversion...

  1. Lipid Replacement Therapy Drink Containing a Glycophospholipid Formulation Rapidly and Significantly Reduces Fatigue While Improving Energy and Mental Clarity

    Directory of Open Access Journals (Sweden)

    Robert Settineri

    2011-08-01

    Full Text Available Background: Fatigue is the most common complaint of patients seeking general medical care and is often treated with stimulants. It is also important in various physical activities of relatively healthy men and women, such as sports performance. Recent clinical trials using patients with chronic fatigue have shown the benefit of Lipid Replacement Therapy in restoring mitochondrial electron transport function and reducing moderate to severe chronic fatigue. Methods: Lipid Replacement Therapy was administered for the first time as an all-natural functional food drink (60 ml containing polyunsaturated glycophospholipids but devoid of stimulants or herbs to reduce fatigue. This preliminary study used the Piper Fatigue Survey instrument as well as a supplemental questionnaire to assess the effects of the glycophospholipid drink on fatigue and the acceptability of the test drink in adult men and women. A volunteer group of 29 subjects of mean age 56.2±4.5 years with various fatigue levels were randomly recruited in a clinical health fair setting to participate in an afternoon open label trial on the effects of the test drink. Results: Using the Piper Fatigue instrument overall fatigue among participants was reduced within the 3-hour seminar by a mean of 39.6% (p<0.0001. All of the subcategories of fatigue showed significant reductions. Some subjects responded within 15 minutes, and the majority responded within one hour with increased energy and activity and perceived improvements in cognitive function, mental clarity and focus. The test drink was determined to be quite acceptable in terms of taste and appearance. There were no adverse events from the energy drink during the study.Functional Foods in Health and Disease 2011; 8:245-254Conclusions: The Lipid Replacement Therapy functional food drink appeared to be a safe, acceptable and potentially useful new method to reduce fatigue, sustain energy and improve perceptions of mental function.

  2. An improved chaotic fruit fly optimization based on a mutation strategy for simultaneous feature selection and parameter optimization for SVM and its applications.

    Science.gov (United States)

    Ye, Fei; Lou, Xin Yuan; Sun, Lin Fu

    2017-01-01

    This paper proposes a new support vector machine (SVM) optimization scheme based on an improved chaotic fly optimization algorithm (FOA) with a mutation strategy to simultaneously perform parameter setting turning for the SVM and feature selection. In the improved FOA, the chaotic particle initializes the fruit fly swarm location and replaces the expression of distance for the fruit fly to find the food source. However, the proposed mutation strategy uses two distinct generative mechanisms for new food sources at the osphresis phase, allowing the algorithm procedure to search for the optimal solution in both the whole solution space and within the local solution space containing the fruit fly swarm location. In an evaluation based on a group of ten benchmark problems, the proposed algorithm's performance is compared with that of other well-known algorithms, and the results support the superiority of the proposed algorithm. Moreover, this algorithm is successfully applied in a SVM to perform both parameter setting turning for the SVM and feature selection to solve real-world classification problems. This method is called chaotic fruit fly optimization algorithm (CIFOA)-SVM and has been shown to be a more robust and effective optimization method than other well-known methods, particularly in terms of solving the medical diagnosis problem and the credit card problem.

  3. Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognitive responses in urban children.

    Directory of Open Access Journals (Sweden)

    Lilian eCalderon-Garciduenas

    2013-08-01

    Full Text Available Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children. We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1 and/or inflammatory mediators in MCMA children. Thirty g of dark cocoa with 680 mg of total flavonols were given daily for 10.11± 3.4 days (range 9 to 24 days to 18 children (10.55yrs, SD =1.45; 11F/7M. Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p=0.0002. Fifteen children (83% showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer’s and Parkinson’s diseases.

  4. Medial grasping sutures significantly improve load to failure of the rotator cuff suture bridge repair.

    Science.gov (United States)

    Awwad, George E; Eng, Kevin; Bain, Gregory I; McGuire, Duncan; Jones, Claire F

    2014-05-01

    The suture bridge (SB) transosseous-equivalent rotator cuff repair reduces re-tear rates compared with single-row or other double-row constructs. However, failure rates continue to be high, especially in large and massive tears. The aim of this study was to assess the biomechanical performance of a new SB repair with use of a medial grasping suture compared with the traditional SB repair. Seven matched pairs of sheep infraspinatus tendons were randomly assigned to either SB or suture bridge with grasping suture (SBGS) repair. Each construct was subjected to cyclic loading and then loaded until failure under displacement control in a materials testing machine. Footprint displacement, ultimate load to failure, and mode of failure were assessed. The rotator cuff footprint displacement was less during tensile loading with the addition of the medial grasping suture. The ultimate load to failure was significantly greater for the SBGS repair group than for the SB repair group (334.0 N vs 79.8 N). The mode of failure was the tendon pulling off the footprint in all cases (type 1 tear). There were no failures in which the tendon tore at the medial row of anchors, leaving part of the tendon still on the footprint (type 2 tear). The addition of a medial grasping suture significantly improved the ultimate load to failure and reduced the footprint displacement of the SB rotator cuff repair in a biomechanical model. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  5. Optimizing available water capacity using microwave satellite data for improving irrigation management

    Science.gov (United States)

    Gupta, Manika; Bolten, John; Lakshmi, Venkat

    2015-04-01

    This work addresses the improvement of available water capacity by developing a technique for estimating soil hydraulic parameters through the utilization of satellite-retrieved near surface soil moisture. The prototype involves the usage of Monte Carlo analysis to assimilate historical remote sensing soil moisture data available from the Advanced Microwave Scanning Radiometer (AMSR-E) within the hydrological model. The main hypothesis used in this study is that near-surface soil moisture data contain useful information that can describe the effective hydrological conditions of the basin such that when appropriately In the method followed in this study the hydraulic parameters are derived directly from information on the soil moisture state at the AMSR-E footprint scale and the available water capacity is derived for the root zone by coupling of AMSR-E soil moisture with the physically-based hydrological model. The available capacity water, which refers to difference between the field capacity and wilting point of the soil and represent the soil moisture content at 0.33 bar and 15 bar respectively is estimated from the soil hydraulic parameters using the van Genuchten equation. The initial ranges of soil hydraulic parameters are taken in correspondence with the values available from the literature based on Soil Survey Geographic (SSURGO) database within the particular AMSR-E footprint. Using the Monte Carlo simulation, the ranges are narrowed in the region where simulation shows a good match between predicted and near-surface soil moisture from AMSR-E. In this study, the uncertainties in accurately determining the parameters of the nonlinear soil water retention function for large-scale hydrological modeling is the focus of the development of the Bayesian framework. Thus, the model forecasting has been combined with the observational information to optimize the model state and the soil hydraulic parameters simultaneously. The optimization process is divided into

  6. Experimental and Numerical Optimization of a High-Lift System to Improve Low-Speed Performance, Stability, and Control of an Arrow-Wing Supersonic Transport

    Science.gov (United States)

    Hahne, David E.; Glaab, Louis J.

    1999-01-01

    An investigation was performed to evaluate leading-and trailing-edge flap deflections for optimal aerodynamic performance of a High-Speed Civil Transport concept during takeoff and approach-to-landing conditions. The configuration used for this study was designed by the Douglas Aircraft Company during the 1970's. A 0.1-scale model of this configuration was tested in the Langley 30- by 60-Foot Tunnel with both the original leading-edge flap system and a new leading-edge flap system, which was designed with modem computational flow analysis and optimization tools. Leading-and trailing-edge flap deflections were generated for the original and modified leading-edge flap systems with the computational flow analysis and optimization tools. Although wind tunnel data indicated improvements in aerodynamic performance for the analytically derived flap deflections for both leading-edge flap systems, perturbations of the analytically derived leading-edge flap deflections yielded significant additional improvements in aerodynamic performance. In addition to the aerodynamic performance optimization testing, stability and control data were also obtained. An evaluation of the crosswind landing capability of the aircraft configuration revealed that insufficient lateral control existed as a result of high levels of lateral stability. Deflection of the leading-and trailing-edge flaps improved the crosswind landing capability of the vehicle considerably; however, additional improvements are required.

  7. Optimizing Vacuum Assisted Resin Transfer Moulding (VARTM) Processing Parameters to Improve Part Quality

    Science.gov (United States)

    Polowick, Christopher

    The Low Cost Composites (LCC) group at Carleton University is studying out-of-autoclave composite manufacturing processes such as Vacuum Assisted Resin Transfer Moulding (VARTM) and Closed Cavity Bag Moulding (CCBM). These processes are used to produce inexpensive and high performance components for the GeoSurv II, an Unmanned Aerial Vehicle (UAV) being developed at Carleton University. This research has focused on optimizing VARTM processing parameters to reduce the weight and improve the strength and surface finish of GeoSurv II composite components. A simulation was developed to model resin flow through in VARTM infusions and was used to simulate mould filling and resin emptying of the GeoSurv II inverted V-empennage and mission avionics hatch. The resin infusion schemes of these parts were designed to ensure full preform resin saturation, and minimize thickness variations. An experimental study of the effects of the presence of a corner on composite thickness, void content, and strength was conducted. It was found that inside corners result in local increases in thickness and void content due to poor preform compaction. A novel bagging technique was developed to improve corner compaction, and this technique was shown to reduce thickness variability and void content. The strength, void content, and thickness variation were found to be heavily dependent on corner radius, with corner radii greater than 6.4 mm displaying the greatest improvement in performance for the layups considered. The design of the empennage and hatch mould incorporated the results of this study to improve the quality of these components.

  8. Particle Swarm Optimization Based Feature Enhancement and Feature Selection for Improved Emotion Recognition in Speech and Glottal Signals

    Science.gov (United States)

    Muthusamy, Hariharan; Polat, Kemal; Yaacob, Sazali

    2015-01-01

    In the recent years, many research works have been published using speech related features for speech emotion recognition, however, recent studies show that there is a strong correlation between emotional states and glottal features. In this work, Mel-frequency cepstralcoefficients (MFCCs), linear predictive cepstral coefficients (LPCCs), perceptual linear predictive (PLP) features, gammatone filter outputs, timbral texture features, stationary wavelet transform based timbral texture features and relative wavelet packet energy and entropy features were extracted from the emotional speech (ES) signals and its glottal waveforms(GW). Particle swarm optimization based clustering (PSOC) and wrapper based particle swarm optimization (WPSO) were proposed to enhance the discerning ability of the features and to select the discriminating features respectively. Three different emotional speech databases were utilized to gauge the proposed method. Extreme learning machine (ELM) was employed to classify the different types of emotions. Different experiments were conducted and the results show that the proposed method significantly improves the speech emotion recognition performance compared to previous works published in the literature. PMID:25799141

  9. In vitro activity of colistin against biofilm by Pseudomonas aeruginosa is significantly improved under "cystic fibrosis-like" physicochemical conditions.

    Science.gov (United States)

    Pompilio, Arianna; Crocetta, Valentina; Pomponio, Stefano; Fiscarelli, Ersilia; Di Bonaventura, Giovanni

    2015-08-01

    The impact of physicochemical conditions observed in cystic fibrosis (CF) lung on colistin activity against both planktonic and biofilm P. aeruginosa cells was evaluated. MIC, minimum bactericidal concentration (MBC), and minimum biofilm eradication concentration (MBEC) values were assessed against 12 CF strains both under "CF-like" (anaerobiosis, pH6.4) and "standard" (aerobiosis, pH7.4) conditions. The activity of colistin was significantly higher under "CF-like" conditions compared to "standard" ones, both against planktonic (MIC90: 1 and 4 μg/mL, respectively) and biofilm (MBEC90: 512 and 1.024 μg/mL, respectively) cells, as confirmed by scanning electron microscopy. Improved activity was not related to biofilm matrix amount. It may be necessary to adequately "rethink" the protocols used for in vitro assessment of colistin activity, by considering physicochemical and microbiological features in the CF lung at the site of infection. This could provide a more favorable therapeutic index, rationale for administration of lower doses, probably resulting in reduced toxicity and emergence of resistant clones. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Preprocessing significantly improves the peptide/protein identification sensitivity of high-resolution isobarically labeled tandem mass spectrometry data.

    Science.gov (United States)

    Sheng, Quanhu; Li, Rongxia; Dai, Jie; Li, Qingrun; Su, Zhiduan; Guo, Yan; Li, Chen; Shyr, Yu; Zeng, Rong

    2015-02-01

    Isobaric labeling techniques coupled with high-resolution mass spectrometry have been widely employed in proteomic workflows requiring relative quantification. For each high-resolution tandem mass spectrum (MS/MS), isobaric labeling techniques can be used not only to quantify the peptide from different samples by reporter ions, but also to identify the peptide it is derived from. Because the ions related to isobaric labeling may act as noise in database searching, the MS/MS spectrum should be preprocessed before peptide or protein identification. In this article, we demonstrate that there are a lot of high-frequency, high-abundance isobaric related ions in the MS/MS spectrum, and removing isobaric related ions combined with deisotoping and deconvolution in MS/MS preprocessing procedures significantly improves the peptide/protein identification sensitivity. The user-friendly software package TurboRaw2MGF (v2.0) has been implemented for converting raw TIC data files to mascot generic format files and can be downloaded for free from https://github.com/shengqh/RCPA.Tools/releases as part of the software suite ProteomicsTools. The data have been deposited to the ProteomeXchange with identifier PXD000994.

  11. Sirolimus-based therapy following early cyclosporine withdrawal provides significantly improved renal histology and function at 3 years.

    Science.gov (United States)

    Mota, Alfredo; Arias, Manuel; Taskinen, Eero I; Paavonen, Timo; Brault, Yves; Legendre, Christophe; Claesson, Kerstin; Castagneto, Marco; Campistol, Josep M; Hutchison, Brian; Burke, James T; Yilmaz, Sedar; Häyry, Pekka; Neylan, John F

    2004-06-01

    Graft function and histology are predictive of renal transplant survival. The Rapamune Maintenance Regimen study demonstrated that early cyclosporine (CsA) withdrawal from a sirolimus (SRL)-CsA-steroid (ST) regimen improved renal function and blood pressure. We report the protocol-mandated biopsy findings from that study. Renal transplant patients (n = 430) receiving SRL-CsA-ST were randomized at 3 months after transplantation to remain on SRL-CsA-ST, or to have CsA withdrawn (SRL-ST group). Protocol-mandated biopsies were performed at engraftment and at 12 and 36 months. Two pathologists blindly evaluated 484 biopsies to obtain the Chronic Allograft Damage Index (CADI) scores. At 36 months among patients with serial biopsies (n = 63), the mean CADI score was significantly lower with SRL-ST(4.70 vs. 3.20, p = 0.003), as was the mean tubular atrophy score (0.77 vs. 0.32, p renal histology and function.

  12. A fast and portable Re-Implementation of Piskunov and Valenti's Optimal-Extraction Algorithm with improved Cosmic-Ray Removal and Optimal Sky Subtraction

    OpenAIRE

    Ritter, A.; Hyde, E. A.; Q. A. Parker

    2013-01-01

    We present a fast and portable re-implementation of Piskunov and Valenti's optimal-extraction algorithm (Piskunov & Valenti, 2002} in C/C++ together with full uncertainty propagation, improved cosmic-ray removal, and an optimal background-subtraction algorithm. This re-implementation can be used with IRAF and most existing data-reduction packages and leads to signal-to-noise ratios close to the Poisson limit. The algorithm is very stable, operates on spectra from a wide range of instruments (...

  13. Intravenous thrombolysis before endovascular therapy for large vessel strokes can lead to significantly higher hospital costs without improving outcomes.

    Science.gov (United States)

    Rai, Ansaar T; Boo, SoHyun; Buseman, Chelsea; Adcock, Amelia K; Tarabishy, Abdul R; Miller, Maurice M; Roberts, Thomas D; Domico, Jennifer R; Carpenter, Jeffrey S

    2017-01-06

    Limited efficacy of IV recombinant tissue plasminogen activator (rt-PA) for large vessel occlusions (LVO) raises doubts about its utility prior to endovascular therapy. To compare outcomes and hospital costs for anterior circulation LVOs (middle cerebral artery, internal carotid artery terminus (ICA-T)) treated with either primary endovascular therapy alone (EV-Only) or bridging therapy (IV+EV)). A single-center retrospective analysis was performed. Clinical and demographic data were collected prospectively and relevant cost data were obtained for each patient in the study. 90 consecutive patients were divided into EV-Only (n=52) and IV+EV (n=38) groups. There was no difference in demographics, stroke severity, or clot distribution. The mean (SD) time to presentation was 5:19 (4:30) hours in the EV-Only group and 1:46 (0:52) hours in the IV+EV group (pIV+EV 31 (81.6%) (p=0.12). Favorable outcome: EV-Only 26 (50%) versus IV+EV 22 (58%) (p=0.45). For patients presenting within 4.5 hours (n=64): Recanalization: EV-Only 21/26 (81%) versus IV+EV 31/38 (81.6%) (p=0.93). Favorable outcome: EV-Only 14/26 (54%) versus IV+EV 22/38 (58%) (p=0.75). There was no significant difference in rates of hemorrhage, mortality, home discharge, or length of stay. A stent retriever was used in 67 cases (74.4%), with similar recanalization, outcomes, and number of passes in the EV-Only and IV+EV groups. The mean (SD) total hospital cost was $33 810 (13 505) for the EV-Only group and $40 743 (17 177) for the IV+EV group (p=0.02). The direct cost was $23 034 (8786) for the EV-Only group and $28 711 (11 406) for the IV+EV group (p=0.007). These significantly higher costs persisted for the subgroup presenting in IV rt-PA administration independently predicted higher hospital costs. IV rt-PA did not improve recanalization, thrombectomy efficacy, functional outcomes, or length of stay. Combined therapy was associated with significantly higher total and direct hospital costs

  14. Optimization of frequency lowering algorithms for getting the highest speech intelligibility improvement by hearing loss simulation.

    Science.gov (United States)

    Arıöz, Umut; Günel, Banu

    2015-06-01

    High frequency hearing loss is a growing problem for both children and adults. To overcome this impairment, different frequency lowering methods (FLMs) were tried from 1930s, however no satisfaction was provided up to now. In this study, for getting higher speech intelligibility, eight combinations of FLMs which were designed originally were tried with simulated sounds onto normal hearing subjects. These improvements were calculated by the difference with standard hearing aid method, amplification. High frequency hearing loss was simulated with the combined suprathreshold effects. An offline study was carried out for each subject for determining the significant methods used in modified rhyme test (MRT) (Subjective measure for intelligibility). Significant methods were determined according to their speech intelligibility index (SII) (Objective measure for intelligibility). All different cases were tried under four noisy environments and a noise free environment. Twelve hearing impaired subjects were simulated by hearing loss simulation (HLS). MRT was developed for Turkish language as a first time. As the results of improvements, total 71 cases were statistically significant for twelve subjects. Eighty-three percent success of FLMs was achieved against amplification for being an alternative method of amplification in noisy environments. For four subjects, all significant methods gave higher improvements than amplification. As conclusion, specific method recommendations for different noisy environments were done for each subject for getting more speech intelligibility.

  15. Optimizing protein and energy intake in hospitals by improving individualized meal serving, hosting and the eating environment

    DEFF Research Database (Denmark)

    Holst, Mette; Beermann, Tina; Mortensen, Marie Nerup

    2017-01-01

    ). Energy intake improved for the entire group, albeit not significantly (P = 0.862). Patients reported being happy with the interventions regarding individualized food serving, nurse communication, and improved meal environments. CONCLUSION: Only insignificant improvements to overall energy intake were...

  16. Optimize BP Neural Network by an Improved Particle Swarm Optimization to Implement Nuclide Identification%一种改进粒子群算法优化BP神经网络实现核素识别方法

    Institute of Scientific and Technical Information of China (English)

    刘议聪; 朱泓光; 宋永强

    2016-01-01

    To get the global optimal point, propose an optimize BP neural network by an improved particle swarm optimization (PSO) to implement nuclide identification. It changes inertia weight and learning factor dynamically with self-adaption to optimize the weight value and threshold value of BP neural network. It gets the global optimal value of the particle swarm by training BP neural network to identify models. Finally, it implements nuclide identification by using the optimal weight and threshold value. The experiment shows our proposed method can not only converge to the optimal value faster but also do a good balance between local search and global search. Therefore, it significantly improves the convergence speed and the accuracy of nuclide identification.%为获得全局最优点,提出一种改进粒子群算法优化BP神经网络实现核素识别方法.该算法用一种动态改变惯性权重与学习因子的自适应方法,优化BP神经网络的阈值与权值,通过训练BP神经网络识别模型得到粒子群的全局最优解,利用最优权值与阈值实现核素识别.分析结果表明:该方法不仅能更快地收敛于最优解,同时能更好地平衡全局搜索和局部搜索能力,有效地改善算法的收敛速度和识别精度.

  17. Elastically Shaped Wing Optimization and Aircraft Concept for Improved Cruise Efficiency

    Science.gov (United States)

    Nguyen, Nhan; Trinh, Khanh; Reynolds, Kevin; Kless, James; Aftosmis, Michael; Urnes, James, Sr.; Ippolito, Corey

    2013-01-01

    This paper presents the findings of a study conducted tn 2010 by the NASA Innovation Fund Award project entitled "Elastically Shaped Future Air Vehicle Concept". The study presents three themes in support of meeting national and global aviation challenges of reducing fuel burn for present and future aviation systems. The first theme addresses the drag reduction goal through innovative vehicle configurations via non-planar wing optimization. Two wing candidate concepts have been identified from the wing optimization: a drooped wing shape and an inflected wing shape. The drooped wing shape is a truly biologically inspired wing concept that mimics a seagull wing and could achieve about 5% to 6% drag reduction, which is aerodynamically significant. From a practical perspective, this concept would require new radical changes to the current aircraft development capabilities for new vehicles with futuristic-looking wings such as this concept. The inflected wing concepts could achieve between 3% to 4% drag reduction. While the drag reduction benefit may be less, the inflected-wing concept could have a near-term impact since this concept could be developed within the current aircraft development capabilities. The second theme addresses the drag reduction goal through a new concept of elastic wing shaping control. By aeroelastically tailoring the wing shape with active control to maintain optimal aerodynamics, a significant drag reduction benefit could be realized. A significant reduction in fuel burn for long-range cruise from elastic wing shaping control could be realized. To realize the potential of the elastic wing shaping control concept, the third theme emerges that addresses the drag reduction goal through a new aerodynamic control effector called a variable camber continuous trailing edge flap. Conventional aerodynamic control surfaces are discrete independent surfaces that cause geometric discontinuities at the trailing edge region. These discontinuities promote

  18. Molecular characterization of forest soil based Paenibacillus elgii and optimization of various culture conditions for its improved antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Dileep eKumar BS

    2015-10-01

    Full Text Available Microorganisms have provided a bounty of bioactive secondary metabolites with very exciting biological activities such as antibacterial, antifungal antiviral, and anticancer, etc. The present study aims at the optimization of culture conditions for improved antimicrobial production of Paenibacillus elgii obtained from Wayanad forest of Western Ghats region of Kerala, India. A bacterial strain isolated from the Western Ghats forest soil of Wayanad, Kerala, India was identified as P. elgii by 16S rRNA gene sequencing. P. elgii recorded significant board spectrum activity against all human and plant pathogenic microorganism tested except Candida albicans. It has been well known that even minor variations in the fermentation medium may impact not only the quantity of desired bioactive metabolites but also the general metabolic profile of the producing microorganisms. Thus, further studies were carried out to assess the impact of medium components on the antimicrobial production of P. elgii and to optimize an ideal fermentation medium to maximize its antimicrobial production. Out of three media [nutrient broth (NA, Luria broth (LB and Trypticase soy broth (TSB] used for fermentation, TSB medium recorded significant activity. Glucose and meat peptone were identified as the best carbon and nitrogen sources, which significantly affected the antibiotic production when supplemented with TSB medium. Next the effect of various fermentation conditions such as temperature, pH and incubation time on the production of antimicrobial compounds was studied on TSB+glucose+meat peptone and an initial pH of 7 and a temperature of 30ºC for 3 days were found to be optimum for maximum antimicrobial production. The results indicate that medium composition in the fermentation media along with cultural parameters plays a vital role in the enhanced production of antimicrobial substances.

  19. The optimization of improved mean shift object tracking in embedded multicore DSP parallel system

    Science.gov (United States)

    Tian, Li; Zhou, Fugen; Meng, Cai; Hu, Congliang

    2014-11-01

    This paper proposes a more robust and efficient Mean Shift object tracking algorithm which is optimized for embedded multicore DSP Parallel system. Firstly, the RGB image is transformed into HSV image which is robust in many aspects such as lighting changes. Then, the color histogram model is used in the back projection process to generate the color probability distribution. Secondly, the size and position of search window are initialized in the first frame, and Mean Shift algorithm calculates the center position of the target and adjusts the search window automatically both in size and location, according to the result of the previous frame. Finally, since the multicore DSP system is commonly adopted in the embedded application such as seeker and an optical scout system, we implement the proposed algorithm in the TI multicore DSP system to meet the need of large amount computation. For multicore parallel computing, the explicit IPC based multicore framework is designed which outperforms OpenMP standard. Moreover, the parallelisms of 8 functional units and cross path data fetch capability of C66 core are utilized to accelerate the computation of iteration in Mean Shift algorithm. The experimental results show that the algorithm has good performance in complex scenes such as deformation, scale change and occlusion, simultaneously the proposed optimization method can significantly reduce the computation time.

  20. Optimization of low-NO{sub x} overfire air systems to improve boiler performance

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, R.E.; Shiomoto, G.H.; Quartucy [Fossil Energy Research Corporation, Laguna Hills, CA (United States)

    1996-05-01

    Overfire air (OFA) is a common post-retrofit NO{sub x} control measure that can adversely impact coal-fired utility boiler performance if not properly implemented. Some utilities have experienced a significant increase in fly ash carbon content, difficulty in maintaining efficient operating O{sub 2} levels, and changes in furnace heat absorption as the result of installing OFA systems. Although staged combustion conditions and coal properties have often been cited as reasons for increased fly ash carbon content and LOI, the importance of optimizing OFA system performance during post-retrofit commissioning and warranty testing has not been adequately recognized. This paper outlines combustion diagnostic and analysis techniques that have been successfully used to evaluate OFA mixing, penetration and combustion uniformity on typical coal-fired utility boilers. Field test data is provided illustrating the results of combustion diagnostic testing on several units where the distribution of air flow to the OFA ports was not well balanced or the OFA penetration and mixing, were not sufficient to achieve uniform combustion. The paper includes a discussion of instrumentation used to adjust OFA parameters to optimize both NO{sub x} emissions and boiler performance. OFA tuning at one 250 MW tangentially-fired unit reduced the O{sub 2} level where CO emissions were first encountered from 4.25 percent O{sub 2} to less than three percent O{sub 2} at the economizer exit.

  1. Improving Soft FEC Performance for Higher-Order Modulations by Bit Mapper Optimization

    CERN Document Server

    Häger, Christian; Brännström, Fredrik; Alvarado, Alex; Agrell, Erik

    2014-01-01

    Soft forward error correction with higher-order modulations is often implemented in practice via the pragmatic bit-interleaved coded modulation paradigm, where a single binary code is mapped to a nonbinary modulation. In this paper, we study the optimization of the mapping of the coded bits to the modulation bits for a polarization-multiplexed fiber-optical system without optical inline dispersion compensation. Our focus is on protograph-based low-density parity-check (LDPC) codes which allow for an efficient hardware implementation, suitable for high-speed optical communications. The optimization is applied to the ARJ4A protograph family, and further extended to protograph-based spatially coupled LDPC codes assuming a windowed decoder. Full field simulations via the split-step Fourier method are used to verify the analysis. The results show performance gains of up to 0.25 dB, which translate into a possible extension of the transmission reach by roughly up to 8%, without significantly increasing the system c...

  2. Networked Timetable Stability Improvement Based on a Bilevel Optimization Programming Model

    Directory of Open Access Journals (Sweden)

    Xuelei Meng

    2014-01-01

    Full Text Available Train timetable stability is the possibility to recover the status of the trains to serve as arranged according to the original timetable when the trains are disturbed. To improve the train timetable stability from the network perspective, the bilevel programming model is constructed, in which the upper level programming is to optimize the timetable stability on the network level and the lower is to improve the timetable stability on the dispatching railway segments. Timetable stability on the network level is defined with the variances of the utilization coefficients of the section capacity and station capacity. Weights of stations and sections are decided by the capacity index number and the degrees. The lower level programming focuses on the buffer time distribution plan of the trains operating on the sections and stations, taking the operating rules of the trains as constraints. A novel particle swarm algorithm is proposed and designed for the bilevel programming model. The computing case proves the feasibility of the model and the efficiency of the algorithm. The method outlined in this paper can be embedded in the networked train operation dispatching system.

  3. A novel fault tolerant permanent magnet synchronous motor with improved optimal torque control for aerospace application

    Directory of Open Access Journals (Sweden)

    Guo Hong

    2015-04-01

    Full Text Available Improving fault tolerant performance of permanent magnet synchronous motor has always been the central issue of the electrically supplied actuator for aerospace application. In this paper, a novel fault tolerant permanent magnet synchronous motor is proposed, which is characterized by two stators and two rotors on the same shaft with a circumferential displacement of mechanical angle of 4.5°. It helps to reduce the cogging torque. Each segment of the stator and the rotor can be considered as an 8-pole/10-slot five-phase permanent magnet synchronous motor with concentrated, single-layer and alternate teeth wound winding, which enhance the fault isolation capacity of the motor. Furthermore, the motor has high phase inductance to restrain the short-circuit current. In addition, an improved optimal torque control strategy is proposed to make the motor work well under the open-circuit fault and short-circuit fault conditions. Simulation and experiment results show that the proposed fault tolerant motor system has excellent fault tolerant capacity, which is able to operate continuously under the third open-circuit fault and second short-circuit fault condition without system performance degradation, which was not available earlier.

  4. Using Interior Point Method Optimization Techniques to Improve 2- and 3-Dimensional Models of Earth Structures

    Science.gov (United States)

    Zamora, A.; Gutierrez, A. E.; Velasco, A. A.

    2014-12-01

    2- and 3-Dimensional models obtained from the inversion of geophysical data are widely used to represent the structural composition of the Earth and to constrain independent models obtained from other geological data (e.g. core samples, seismic surveys, etc.). However, inverse modeling of gravity data presents a very unstable and ill-posed mathematical problem, given that solutions are non-unique and small changes in parameters (position and density contrast of an anomalous body) can highly impact the resulting model. Through the implementation of an interior-point method constrained optimization technique, we improve the 2-D and 3-D models of Earth structures representing known density contrasts mapping anomalous bodies in uniform regions and boundaries between layers in layered environments. The proposed techniques are applied to synthetic data and gravitational data obtained from the Rio Grande Rift and the Cooper Flat Mine region located in Sierra County, New Mexico. Specifically, we improve the 2- and 3-D Earth models by getting rid of unacceptable solutions (those that do not satisfy the required constraints or are geologically unfeasible) given the reduction of the solution space.

  5. MPPT for Photovoltaic System Using Multi-objective Improved Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Xuecheng Zhao

    2013-07-01

    Full Text Available Making full use of abundant renewable solar energy through the development of photovoltaic (PV technology is an effective means to solve the problems such as difficulty in electricity supply and energy shortages in remote rural areas. In order to improve the electricity generating efficiency of PV cells, it is necessary to track the maximum power point of PV array, which is difficult to make under partially shaded conditions due to the odds of the appearance of two or more local maximum power points., In this paper, a control algorithm of maximum power point tracking (MPPT based on improved particle swarm optimization (IPSO algorithm is presented for PV systems. Firstly, the current in maximum power point is searched with the IPSO algorithm, and then the real maximum power point is tracked through controlling the output current of PV array.,. The MPPT method based on IPSO algorithm is established and simulated with Matlab / Simulink, and meanwhile, the comparison between IPSO MPPT algorithm and traditional MPPT algorithm is also performed in this paper. It is proved through simulation and experimental results that the IPSO algorithm has good performances and very fast response even to partial shaded PV modules, , which ensures the stability of PV system.  

  6. Suction against resistance: a new breathing technique to significantly improve the blood flow ratio of the superior and inferior vena cava

    Energy Technology Data Exchange (ETDEWEB)

    Gutzeit, Andreas [Clinical Research Unit of St. Anna Hospital Luzern, Institute of Radiology and Nuclear Medicine, Luzern (Switzerland); Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Cantonal Hospital, Department of Radiology, Winterthur (Switzerland); Roos, Justus E. [Duke University, Department of Radiology, Durham, NC (United States); Hergan, Klaus [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Weymarn, Constantin von; Reischauer, Carolin; Froehlich, Johannes M. [Clinical Research Unit of St. Anna Hospital Luzern, Institute of Radiology and Nuclear Medicine, Luzern (Switzerland); Cantonal Hospital, Department of Radiology, Winterthur (Switzerland); Waelti, Stephan [Cantonal Hospital, Department of Radiology, Winterthur (Switzerland)

    2014-12-15

    Optimal contrast within the pulmonary artery is achieved by the maximum amount of contrast-enhanced blood flowing through the superior vena cava (SVC), while minimum amounts of non-contrasted blood should originate from the inferior vena cava (IVC). This study aims to clarify whether ''suction against resistance'' might optimise this ratio. Phase-contrast pulse sequences on a 1.5T MRI magnet were used for flow quantification mean flow (mL/s), stroke volume (Vol) in the SVC and IVC in volunteers. Different breathing manoeuvers were analysed repeatedly: free breathing; inspiration; expiration; suction against resistance, and Valsalva. To standardise breathing commands, volunteers performed suction and Valsalva manoeuvers with an MR-compatible manometer.??Suction against resistance was associated with a significant drop of the IVC/SVC flow quotient (1.63 [range 1.3-2.0] p < 0.05 at -10 mmHg and 1.48 [1.1-1.9] p < 0.01 at -20 mmHg) corresponding to increased blood flow from SVC and diminished flow originating from the IVC. The remaining breathing commands (free breathing 2.2; inspiration 2.4; expiration 2.4; Valsalva 10 mmHg 2.3; Valsalva 20 mmHg 2.6; and Valsalva 30 mmHg 2.2) showed no differences (p > 0.05).??Suction against resistance caused a significant drop in the IVC/SVC quotient. Theoretically, this breathing manoeuver might significantly improve the enhancement characteristics of CT angiography. (orig.)

  7. A Survey on Optimal Signal Processing Techniques Applied to Improve the Performance of Mechanical Sensors in Automotive Applications

    Science.gov (United States)

    Hernandez, Wilmar

    2007-01-01

    In this paper a survey on recent applications of optimal signal processing techniques to improve the performance of mechanical sensors is made. Here, a comparison between classical filters and optimal filters for automotive sensors is made, and the current state of the art of the application of robust and optimal control and signal processing techniques to the design of the intelligent (or smart) sensors that today's cars need is presented through several experimental results that show that the fusion of intelligent sensors and optimal signal processing techniques is the clear way to go. However, the switch between the traditional methods of designing automotive sensors and the new ones cannot be done overnight because there are some open research issues that have to be solved. This paper draws attention to one of the open research issues and tries to arouse researcher's interest in the fusion of intelligent sensors and optimal signal processing techniques.

  8. Study of Direction Probability and Algorithm of Improved Marriage in Honey Bees Optimization for Weapon Network System

    Institute of Scientific and Technical Information of China (English)

    YANG Chen-guang; TU Xu-yan; CHEN Jie

    2009-01-01

    To solve the weapon network system optimization problem against small raid objects with low attitude, the concept of direction probability and a new evaluation index system are proposed. By calculating the whole damaging probability that changes with the defending angle, the efficiency of the whole weapon network system can be subtly described. With such method, we can avoid the inconformity of the description obtained from the traditional index systems. Three new indexes are also proposed, I.e. Join index, overlap index and cover index, which help manage the relationship among several sub-weapon-networks. By normalizing the computation results with the Sigmoid function, the matching problem between the optimization algorithm and indexes is well settled. Also, the algorithm of improved marriage in honey bees optimization that proposed in our previous work is applied to optimize the embattlement problem. Simulation is carried out to show the efficiency of the proposed indexes and the optimization algorithm.

  9. Automatic Optimizer Generation Method Based on Location and Context Information to Improve Mobile Services

    Directory of Open Access Journals (Sweden)

    Yunsik Son

    2017-01-01

    Full Text Available Several location-based services (LBSs have been recently developed for smartphones. Among these are proactive LBSs, which provide services to smartphone users by periodically collecting background logs. However, because they consume considerable battery power, they are not widely used for various LBS-based services. Battery consumption, in particular, is a significant issue on account of the characteristics of mobile systems. This problem involves a greater service restriction when performing complex operations. Therefore, to successfully enable various services based on location, this problem must be solved. In this paper, we introduce a technique to automatically generate a customized service optimizer for each application, service type, and platform using location and situation information. By using the proposed technique, energy and computing resources can be more efficiently employed for each service. Thus, users should receive more effective LBSs on mobile devices, such as smartphones.

  10. A New Hybrid MGBPSO-GSA Variant for Improving Function Optimization Solution in Search Space

    Directory of Open Access Journals (Sweden)

    Narinder Singh

    2017-03-01

    Full Text Available In this article, a newly hybrid nature-inspired approach (MGBPSO-GSA is developed with a combination of Mean Gbest Particle Swarm Optimization (MGBPSO and Gravitational Search Algorithm (GSA. The basic inspiration is to integrate the ability of exploitation in MGBPSO with the ability of exploration in GSA to synthesize the strength of both approaches. As a result, the presented approach has the automatic balance capability between local and global searching abilities. The performance of the hybrid approach is tested on a variety of classical functions, ie, unimodal, multimodal, and fixed-dimension multimodal functions. Furthermore, Iris data set, Heart data set, and economic dispatch problems are used to compare the hybrid approach with several metaheuristics. Experimental statistical solutions prove empirically that the new hybrid approach outperforms significantly a number of metaheuristics in terms of solution stability, solution quality, capability of local and global optimum, and convergence speed.

  11. Significant improvement of near-UV electroluminescence from ZnO quantum dot LEDs via coupling with carbon nanodot surface plasmons.

    Science.gov (United States)

    Zhang, Cen; Zhu, Feifei; Xu, Haiyang; Liu, Weizhen; Yang, Liu; Wang, Zhongqiang; Ma, Jiangang; Kang, Zhenhui; Liu, Yichun

    2017-10-05

    Short-wavelength LEDs, a hot research topic in modern optoelectronics, have attracted tremendous attention in recent years because of their great application potential in both civil and military domains. Compared to conventional metallic surface-plasmons (SPs), carbon nanodot (CD) SPs with less optical loss and low cost, broader SP resonant frequency and good biocompatibility are expected to provide more prominent luminescence enhancement for light emitters. Herein, SP-enhanced near-UV emission quantum dot LEDs (Q-LED) were fabricated via introducing CDs into p-GaN/Al2O3/ZnO Q-LEDs by optimizing the molar ratio of ZnO quantum dots to CDs and a significant enhancement (∼20-fold) of the near-UV electroluminescence (EL) intensity from the ZnO-based Q-LEDs was achieved. Time-resolved spectroscopy studies reveal that the observed luminescence enhancement arises due to the resonant coupling between ZnO excitons and CD SPs. The current study not only demonstrates a feasible way to acquire near-UV emission from all-inorganic Q-LEDs, but also provides an effective strategy to enhance the EL intensity of these QD light emitters, which can further be extended to other types of light-emitting devices to improve EL efficiency.

  12. Development of olmesartan medoxomil optimized nanosuspension using the Box-Behnken design to improve oral bioavailability.

    Science.gov (United States)

    Nagaraj, K; Narendar, D; Kishan, V

    2017-03-27

    The aim of the present investigation was to enhance the oral bioavailability of olmesartan medoxomil by improving its solubility and dissolution rate by preparing nanosuspension (OM-NS), using the Box-Behnken design. In this, four factors were evaluated at three levels. Independent variables include: concentration of drug (X1), concentration of surfactant (X2), concentration of polymer (X3) and number of homogenization cycles (X4). Based on preliminary studies, the size (Y1), zeta potential (ZP) (Y2) and % drug release at 5 min (Y3) were chosen as dependent responses. OM-NS was prepared by high pressure homogenization method. The size, PDI, ZP, assay, in vitro release and morphology of OM-NS were characterized. Further, the pharmacokinetic (PK) behavior of OM-NS was evaluated in male wistar rats. Statistically optimized OM-NS formulation exhibited mean particle size of 492 nm, ZP of -27.9 mV and 99.29% release in 5 min. OM-NS showed more than four times increase in its solubility than pure OM. DSC and XRD analyses indicated that the drug incorporated into OM-NS was in amorphous form. The morphology of OM-NS was found to be nearly spherical with high dispersity by scanning electron microscopic studies. The PK results showed that OM lyophilized nanosuspension (NS) exhibited improved PK properties compared to coarse powder suspension and marketed tablet powder suspension (TS). Oral bioavailability of lyophilized NS was increased by 2.45 and 2.25 folds when compared to marketed TS and coarse powder suspension, respectively. Results of this study lead to conclusion that NS approach was effective in preparing OM formulations with enhanced dissolution and improved oral bioavailability.

  13. A quantitative approach for assessing significant improvements in elite sprint performance: has IGF-1 entered the arena?

    Science.gov (United States)

    Ernst, Simon; Simon, Perikles

    2013-06-01

    The introduction of doping substances and methods in sports triggers noticeable effects on physical performance in metric sports. Here, we use time series analysis to investigate the recent development in male and female elite sprinting performance. Time series displaying the average of the world's top 20 athletes were analyzed employing polynomial spline functions and moving averages. Outstanding changes in performance over time were statistically analyzed by Welch's t-test and by Cohen's measurements of effect. For validation we exemplarily show that our analysis is capable of indicating the effect of the introduction of in- and out-of-competition doping testing on women's shot put as well as the effects of the market introduction of erythropoietin (EPO) and the introduction of EPO and continuous erythropoiesis receptor activator (CERA) testing on 5000 m top 20 male performances. Time series analysis for 100 m men reveals a highly significant (p < 0.001) drop by more than 0.1 s from 2006 to 2011 with a large effect size of 0.952. This is roughly half of the effect size that can be found for the development of the 5000 m performance during the introduction of EPO between 1991 and 1996. While the men's 200 m sprinting performance shows a similar development, the women's 100 m and 200 m sprinting performances only show some minor abnormalities. We will discuss here why the striking sex-specific improvement in sprinting performance is indicative for a novel, very effective doping procedure with insulin-like growth factor-1 (IGF-1) being the primary candidate explaining the observed effects.

  14. Extended-release niacin/laropiprant significantly improves lipid levels in type 2 diabetes mellitus irrespective of baseline glycemic control

    Directory of Open Access Journals (Sweden)

    Bays HE

    2015-02-01

    Full Text Available Harold E Bays,1 Eliot A Brinton,2 Joseph Triscari,3 Erluo Chen,3 Darbie Maccubbin,3 Alexandra A MacLean,3 Kendra L Gibson,3 Rae Ann Ruck,3 Amy O Johnson-Levonas,3 Edward A O’Neill,3 Yale B Mitchel3 1Louisville Metabolic & Atherosclerosis Research Center (L-MARC, Louisville, KY, USA; 2Utah Foundation for Biomedical Research, Salt Lake City, UT, USA; 3Merck & Co, Inc., Whitehouse Station, NJ, USA Background: The degree of glycemic control in patients with type 2 diabetes mellitus (T2DM may alter lipid levels and may alter the efficacy of lipid-modifying agents. Objective: Evaluate the lipid-modifying efficacy of extended-release niacin/laropiprant (ERN/LRPT in subgroups of patients with T2DM with better or poorer glycemic control. Methods: Post hoc analysis of clinical trial data from patients with T2DM who were randomized 4:3 to double-blind ERN/LRPT or placebo (n=796, examining the lipid-modifying effects of ERN/LRPT in patients with glycosylated hemoglobin or fasting plasma glucose levels above and below median baseline levels. Results: At Week 12 of treatment, ERN/LRPT significantly improved low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C, non-high-density lipoprotein cholesterol, triglycerides, and lipoprotein (a, compared with placebo, with equal efficacy in patients above or below median baseline glycemic control. Compared with placebo, over 36 weeks of treatment more patients treated with ERN/LRPT had worsening of their diabetes and required intensification of antihyperglycemic medication, irrespective of baseline glycemic control. Incidences of other adverse experiences were generally low in all treatment groups. Conclusion: The lipid-modifying effects of ERN/LRPT are independent of the degree of baseline glycemic control in patients with T2DM (NCT00485758. Keywords: lipid-modifying agents, hyperglycemia, LDL, HDL, triglycerides

  15. Enhanced decomposition of dyes by hemin-ACF with significant improvement in pH tolerance and stability

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Yuyuan, E-mail: yyy0571@126.com; Mao, Yajun; Huang, Qunfeng; Wang, Lie; Huang, Zhengfu; Lu, Wangyang; Chen, Wenxing, E-mail: wxchen@zstu.edu.cn

    2014-01-15

    Highlights: • ACF-supported hemin allowed enhanced decomposition of dyes compared with bare hemin. • Hemin-ACF exhibited excellent pH tolerance over a wide pH range from acidic to alkaline. • The introduction of ACF accelerated the generation of reactive species by electron transfer from ACF to hemin. -- Abstract: In this study, we evaluated a novel heterogeneous catalytic system (hemin-ACF/H{sub 2}O{sub 2}) based on activated carbon fiber supported hemin for the rapid removal of dyes. Contrast experiments, effects of pH and temperature, and sustained catalytic stability of hemin-ACF for the catalytic decomposition of azo dye RR195 used as a model pollutant were investigated. Surprisingly, the introduction of ACF significantly enhanced the decomposition of dyes by hemin with an obvious improvement in pH tolerance and stability. Inhibition and probe studies combined with electron paramagnetic resonance (EPR) were conducted to ascertain the role of several radicals (·OH, O{sub 2}·{sup −}/HO{sub 2}·, {sup 1}O{sub 2} and Fe{sup IV}=O) on dye degradation. ACF are rich in free electrons, and the π-conjugated macrocyclic structure of hemin may present convenient channels for the transfer of free electrons from the ACF, promoting the generation of hydroxyl radicals and high-valence iron species. These results are promising because they offer new insight for the application of hemin as a catalyzer upon treatment of organic pollutants and contribute to identification of the interaction between support material and catalyzer from a new perspective.

  16. Absorber and gain chip optimization to improve performance from a passively modelocked electrically pumped vertical external cavity surface emitting laser<