On the multi-level solution algorithm for Markov chains
Energy Technology Data Exchange (ETDEWEB)
Horton, G. [Univ. of Erlangen, Nuernberg (Germany)
1996-12-31
We discuss the recently introduced multi-level algorithm for the steady-state solution of Markov chains. The method is based on the aggregation principle, which is well established in the literature. Recursive application of the aggregation yields a multi-level method which has been shown experimentally to give results significantly faster than the methods currently in use. The algorithm can be reformulated as an algebraic multigrid scheme of Galerkin-full approximation type. The uniqueness of the scheme stems from its solution-dependent prolongation operator which permits significant computational savings in the evaluation of certain terms. This paper describes the modeling of computer systems to derive information on performance, measured typically as job throughput or component utilization, and availability, defined as the proportion of time a system is able to perform a certain function in the presence of component failures and possibly also repairs.
A multi-level solution algorithm for steady-state Markov chains
Horton, Graham; Leutenegger, Scott T.
1993-01-01
A new iterative algorithm, the multi-level algorithm, for the numerical solution of steady state Markov chains is presented. The method utilizes a set of recursively coarsened representations of the original system to achieve accelerated convergence. It is motivated by multigrid methods, which are widely used for fast solution of partial differential equations. Initial results of numerical experiments are reported, showing significant reductions in computation time, often an order of magnitude or more, relative to the Gauss-Seidel and optimal SOR algorithms for a variety of test problems. The multi-level method is compared and contrasted with the iterative aggregation-disaggregation algorithm of Takahashi.
Leutenegger, Scott T.; Horton, Graham
1994-01-01
Recently the Multi-Level algorithm was introduced as a general purpose solver for the solution of steady state Markov chains. In this paper, we consider the performance of the Multi-Level algorithm for solving Nearly Completely Decomposable (NCD) Markov chains, for which special-purpose iteractive aggregation/disaggregation algorithms such as the Koury-McAllister-Stewart (KMS) method have been developed that can exploit the decomposability of the the Markov chain. We present experimental results indicating that the general-purpose Multi-Level algorithm is competitive, and can be significantly faster than the special-purpose KMS algorithm when Gauss-Seidel and Gaussian Elimination are used for solving the individual blocks.
Constrained Multi-Level Algorithm for Trajectory Optimization
Adimurthy, V.; Tandon, S. R.; Jessy, Antony; Kumar, C. Ravi
The emphasis on low cost access to space inspired many recent developments in the methodology of trajectory optimization. Ref.1 uses a spectral patching method for optimization, where global orthogonal polynomials are used to describe the dynamical constraints. A two-tier approach of optimization is used in Ref.2 for a missile mid-course trajectory optimization. A hybrid analytical/numerical approach is described in Ref.3, where an initial analytical vacuum solution is taken and gradually atmospheric effects are introduced. Ref.4 emphasizes the fact that the nonlinear constraints which occur in the initial and middle portions of the trajectory behave very nonlinearly with respect the variables making the optimization very difficult to solve in the direct and indirect shooting methods. The problem is further made complex when different phases of the trajectory have different objectives of optimization and also have different path constraints. Such problems can be effectively addressed by multi-level optimization. In the multi-level methods reported so far, optimization is first done in identified sub-level problems, where some coordination variables are kept fixed for global iteration. After all the sub optimizations are completed, higher-level optimization iteration with all the coordination and main variables is done. This is followed by further sub system optimizations with new coordination variables. This process is continued until convergence. In this paper we use a multi-level constrained optimization algorithm which avoids the repeated local sub system optimizations and which also removes the problem of non-linear sensitivity inherent in the single step approaches. Fall-zone constraints, structural load constraints and thermal constraints are considered. In this algorithm, there is only a single multi-level sequence of state and multiplier updates in a framework of an augmented Lagrangian. Han Tapia multiplier updates are used in view of their special role in
Multi-level Algorithm for the Anderson Impurity Model
Chandrasekharan, S.; Yoo, J.; Baranger, H. U.
2004-03-01
We develop a new quantum Monte Carlo algorithm to solve the Anderson impurity model. Instead of integrating out the Fermions, we work in the Fermion occupation number basis and thus have direct access to the Fermionic physics. The sign problem that arises in this formulation can be solved by a multi-level technique developed by Luscher and Weisz in the context of lattice QCD [JHEP, 0109 (2001) 010]. We use the directed-loop algorithm to update the degrees of freedom. Further, this algorithm allows us to work directly in the Euclidean time continuum limit for arbitrary values of the interaction strength thus avoiding time discretization errors. We present results for the impurity susceptibility and the properties of the screening cloud obtained using the algorithm.
A-MMLQ Algorithm for Multi-level Queue Scheduling
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Manupriya Hasija
2013-07-01
Full Text Available This being the era of advancement in computing domain, the emphasis is on better resource scheduling. Scheduling is not confined to dealing multiple tasks by a single processor. It’s a dawn with multiprocessing and multitasking. Although multiprocessor systems impose several overheads but still make the concept amazingly interesting. The scheduling field has taken a whirlwind after the notion of multiprocessing. Many of the uniprocessor algorithms do fit well under the multiprocessor systems but, still necessitating a further development aiming solely on multiprocessor scheduling. This paper thus sketches a new idea to modify and extend the well-known multi-level queue scheduling, taking into account the arrival time/ arrival sequence to conceptualize an innovative scheduling algorithm.
An adaptive multi-level simulation algorithm for stochastic biological systems.
Lester, C; Yates, C A; Giles, M B; Baker, R E
2015-01-14
Discrete-state, continuous-time Markov models are widely used in the modeling of biochemical reaction networks. Their complexity often precludes analytic solution, and we rely on stochastic simulation algorithms (SSA) to estimate system statistics. The Gillespie algorithm is exact, but computationally costly as it simulates every single reaction. As such, approximate stochastic simulation algorithms such as the tau-leap algorithm are often used. Potentially computationally more efficient, the system statistics generated suffer from significant bias unless tau is relatively small, in which case the computational time can be comparable to that of the Gillespie algorithm. The multi-level method [Anderson and Higham, "Multi-level Monte Carlo for continuous time Markov chains, with applications in biochemical kinetics," SIAM Multiscale Model. Simul. 10(1), 146-179 (2012)] tackles this problem. A base estimator is computed using many (cheap) sample paths at low accuracy. The bias inherent in this estimator is then reduced using a number of corrections. Each correction term is estimated using a collection of paired sample paths where one path of each pair is generated at a higher accuracy compared to the other (and so more expensive). By sharing random variables between these paired paths, the variance of each correction estimator can be reduced. This renders the multi-level method very efficient as only a relatively small number of paired paths are required to calculate each correction term. In the original multi-level method, each sample path is simulated using the tau-leap algorithm with a fixed value of τ. This approach can result in poor performance when the reaction activity of a system changes substantially over the timescale of interest. By introducing a novel adaptive time-stepping approach where τ is chosen according to the stochastic behaviour of each sample path, we extend the applicability of the multi-level method to such cases. We demonstrate the
An adaptive multi-level simulation algorithm for stochastic biological systems
Energy Technology Data Exchange (ETDEWEB)
Lester, C., E-mail: lesterc@maths.ox.ac.uk; Giles, M. B.; Baker, R. E. [Mathematical Institute, Woodstock Road, Oxford OX2 6GG (United Kingdom); Yates, C. A. [Department of Mathematical Sciences, University of Bath, Bath BA2 7AY (United Kingdom)
2015-01-14
Discrete-state, continuous-time Markov models are widely used in the modeling of biochemical reaction networks. Their complexity often precludes analytic solution, and we rely on stochastic simulation algorithms (SSA) to estimate system statistics. The Gillespie algorithm is exact, but computationally costly as it simulates every single reaction. As such, approximate stochastic simulation algorithms such as the tau-leap algorithm are often used. Potentially computationally more efficient, the system statistics generated suffer from significant bias unless tau is relatively small, in which case the computational time can be comparable to that of the Gillespie algorithm. The multi-level method [Anderson and Higham, “Multi-level Monte Carlo for continuous time Markov chains, with applications in biochemical kinetics,” SIAM Multiscale Model. Simul. 10(1), 146–179 (2012)] tackles this problem. A base estimator is computed using many (cheap) sample paths at low accuracy. The bias inherent in this estimator is then reduced using a number of corrections. Each correction term is estimated using a collection of paired sample paths where one path of each pair is generated at a higher accuracy compared to the other (and so more expensive). By sharing random variables between these paired paths, the variance of each correction estimator can be reduced. This renders the multi-level method very efficient as only a relatively small number of paired paths are required to calculate each correction term. In the original multi-level method, each sample path is simulated using the tau-leap algorithm with a fixed value of τ. This approach can result in poor performance when the reaction activity of a system changes substantially over the timescale of interest. By introducing a novel adaptive time-stepping approach where τ is chosen according to the stochastic behaviour of each sample path, we extend the applicability of the multi-level method to such cases. We demonstrate the
A cost benefit operator for efficient multi level genetic algorithm searches
Mitchell, George G.; McMullin, Barry; Decraene, James
2007-01-01
In this paper we present a novel cost benefit operator that assists multi level genetic algorithm searches. Through the use of the cost benefit operator, it is possible to dynamically constrain the search of the base level genetic algorithm, to suit the user’s requirements. Initially we review meta-evolutionary (multi-level genetic algorithm) approaches. We note that the current literature has abundant studies on meta-evolutionary GAs. However these approaches have not identified an effici...
Multi-level Threshold Image Segmentation Based on PSNR using Artificial Bee Colony Algorithm
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Cao Yun-Fei
2012-01-01
Full Text Available Image segmentation is still a crucial problem in image processing. It hasn yet been solved very well. In this study, we propose a novel multi-level thresholding image segmentation method based on PSNR using artificial bee colony algorithm (ABCA. PSNR is considered as an objective function of ABCA. The multi-level thresholds (t*1, t*2 ,...., t*n-1, t*n are those maximizing the PSNR. We compare entropy and PSNR in segmenting gray-level images. The experiments results demonstrate proposed method is effective and efficient.
A Novel Multi-Level Trust Algorithm for Mobile Ad Hoc Networks
Institute of Scientific and Technical Information of China (English)
YU Genjian; ZHENG Baoyu
2006-01-01
Firstly, a multilevel trust algorithm for MANET(mobile ad hoc networks) is presented in this paper and the trust level is defined as a three-tuple type in this multilevel trust algorithm. The paper introduces the multilevel trust into MANET, thereby controlling restricted classified information flows among nodes that have different trust levels. Secondly, the infrastructure of MANET that suit to our multi-level trust is presented. Some conclusions are given at lastly.
FUZZY MULTI-LEVEL WAREHOUSE LAYOUT PROBLEM: NEW MODEL AND ALGORITHM
Institute of Scientific and Technical Information of China (English)
Lixing YANG; Yuan FENG
2006-01-01
This paper deals with a multi-level warehouse layout problem under fuzzy environment, in which different types of items need to be placed in a multi-level warehouse and the monthly demand of each item type and horizontal distance traveled by clamp track are treated as fuzzy variables. In order to minimize the total transportation cost, chance-constrained programming model is designed for the problem based on the credibility measure and then tabu search algorithm based on the fuzzy simulation is designed to solve the model. Some mathematical properties of the model are also discussed when the fuzzy variables are interval fuzzy numbers or trapezoidal fuzzy numbers. Finally, a numerical example is presented to show the efficiency of the algorithm.
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M. Setak
2013-01-01
Full Text Available The hub location problem involves a network of origins and destinations over which transportation takes place. There are many studies associated with finding the location of hub nodes and the allocation of demand nodes to these located hub nodes to transfer the only one kind of commodity under one level of service. However, in this study, carrying different commodity types from origin to destination under various levels of services (e.g. price, punctuality, reliability or transit time is studied. Quality of services experienced by users such as speed, convenience, comfort and security of transportation facilities and services is considered as the level of service. In each system, different kinds of commodities with various levels of services can be transmitted. The appropriate level of service that a commodity can be transmitted through is chosen by customer preferences and the specification of the commodity. So, a mixed integer programming formulation for single allocation hub covering location problem, which is based on the idea of transferring multi commodity flows under multi levels of service is presented. These two are applied concepts, multi-commodity and multi-level of service, which make the model's assumptions closer to the real world problems. In addition, a differential evolution algorithm is designed to find near-optimal solutions. The obtained solutions using differential evolution (DE algorithm (upper bound, where its parameters are tuned by response surface methodology, are compared with exact solutions and computed lower bounds by linear relaxation technique to prove the efficiency of proposed DE algorithm.
MULTI-LEVEL KEY DISTRIBUTION ALGORITHM FOR SECRET KEY RECOVERY SYSTEM
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TANAPAT MAHAVEERAWAT
2015-02-01
Full Text Available Most of Multi Agent Key Recovery Systems are proposed from the assumption that Key Recovery Agents in the system have same availability of security service levelagreement and trust. Which mean, secret key will be shared to each Key Recovery Agent in equal secret’s portion. Practically, each Key Recovery Agent may have their own limitation in terms of securityservice level agreement according to economic cost, complexity and risks. This paper proposedMulti Level Key Distribution Algorithm,which the secret key can be managed into portionsharing and assignto each Key Recovery Agent (KRA according to user’s trust. Withproposed algorithm, the experimental result had shown the advantage in secret sharing size and the system had improved initssecurity from the advantage of multilevel secret key distribution capability.
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Siva Prasad Darla
2014-08-01
Full Text Available In this study, a multi level reverse logistics network is developed for a single product. Reverse logistics is a logistic activity beginning from intake of products returned by customers to selling of remanufactured or new products in market; so, it is considered that reverse flow of used products is from various sources like customers, dealers, retailers, manufacturers, etc., to remanufacturer and followed by transportation to secondary market. Due to uncertainties, any traditional supply chain approach to identify potential manufacturing facilities in this situation cannot be employed. Hence, Genetic Algorithm (GA is used for optimization and minimization of various costs involved in reverse logistics process. A sample numerical data is considered to test performance of the proposed model.
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Zhenyang Hui
2016-01-01
Full Text Available Filtering is one of the core post-processing steps for airborne LiDAR point cloud. In recent years, the morphology-based filtering algorithms have proven to be a powerful and efficient tool for filtering airborne LiDAR point cloud. However, most traditional morphology-based algorithms have difficulties in preserving abrupt terrain features, especially when using larger filtering windows. In order to suppress the omission error caused by protruding terrain features, this paper proposes an improved morphological algorithm based on multi-level kriging interpolation. This algorithm is essentially a combination of progressive morphological filtering algorithm and multi-level interpolation filtering algorithm. The morphological opening operation is performed with filtering window gradually downsizing, while kriging interpolation is conducted at different levels according to the different filtering windows. This process is iterative in a top to down fashion until the filtering window is no longer greater than the preset minimum filtering window. Fifteen samples provided by the ISPRS commission were chosen to test the performance of the proposed algorithm. Experimental results show that the proposed method can achieve promising results not only in flat urban areas but also in rural areas. Comparing with other eight classical filtering methods, the proposed method obtained the lowest omission error, and preserved protruding terrain features better.
Yu, Zhenhua; Fu, Xiao; Cai, Yuanli; Vuran, Mehmet C.
2011-01-01
A reliable energy-efficient multi-level routing algorithm in wireless sensor networks is proposed. The proposed algorithm considers the residual energy, number of the neighbors and centrality of each node for cluster formation, which is critical for well-balanced energy dissipation of the network. In the algorithm, a knowledge-based inference approach using fuzzy Petri nets is employed to select cluster heads, and then the fuzzy reasoning mechanism is used to compute the degree of reliability in the route sprouting tree from cluster heads to the base station. Finally, the most reliable route among the cluster heads can be constructed. The algorithm not only balances the energy load of each node but also provides global reliability for the whole network. Simulation results demonstrate that the proposed algorithm effectively prolongs the network lifetime and reduces the energy consumption. PMID:22163802
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Maryam Rouhani Nejad
2016-03-01
Full Text Available Segmentation is one of the most important operations in image processing and computer vision. Normally, all image processing and computer vision applications are related to segmentation as a pre-processing phase. Image thresholding is one of the most useful methods for image segmentation. Various methods have been represented for image thresholding. One method is Kapur thresholding, which is based on maximizing entropy criterion. In this study, a new meta-heuristic algorithm based on imperialist competition algorithm was proposed for multi-level thresholding based on Kapur's entropy. Also, imperialist competitive algorithm is combined with chaotic functions to enhance search potency in problem space. The results of the proposed method have been compared with particle optimization algorithm and genetic algorithm. The findings revealed that the proposed method was superior to other methods.
Two parameter-tuned metaheuristic algorithms for the multi-level lot sizing and scheduling problem
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S.M.T. Fatemi Ghomi
2012-10-01
Full Text Available This paper addresses the problem of lot sizing and scheduling problem for n-products and m-machines in flow shop environment where setups among machines are sequence-dependent and can be carried over. Many products must be produced under capacity constraints and allowing backorders. Since lot sizing and scheduling problems are well-known strongly NP-hard, much attention has been given to heuristics and metaheuristics methods. This paper presents two metaheuristics algorithms namely, Genetic Algorithm (GA and Imperialist Competitive Algorithm (ICA. Moreover, Taguchi robust design methodology is employed to calibrate the parameters of the algorithms for different size problems. In addition, the parameter-tuned algorithms are compared against a presented lower bound on randomly generated problems. At the end, comprehensive numerical examples are presented to demonstrate the effectiveness of the proposed algorithms. The results showed that the performance of both GA and ICA are very promising and ICA outperforms GA statistically.
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Saad M. Darwish
2016-10-01
Full Text Available Quantitative multilevel association rules mining is a central field to realize motivating associations among data components with multiple levels abstractions. The problem of expanding procedures to handle quantitative data has been attracting the attention of many researchers. The algorithms regularly discretize the attribute fields into sharp intervals, and then implement uncomplicated algorithms established for Boolean attributes. Fuzzy association rules mining approaches are intended to defeat such shortcomings based on the fuzzy set theory. Furthermore, most of the current algorithms in the direction of this topic are based on very tiring search methods to govern the ideal support and confidence thresholds that agonize from risky computational cost in searching association rules. To accelerate quantitative multilevel association rules searching and escape the extreme computation, in this paper, we propose a new genetic-based method with significant innovation to determine threshold values for frequent item sets. In this approach, a sophisticated coding method is settled, and the qualified confidence is employed as the fitness function. With the genetic algorithm, a comprehensive search can be achieved and system automation is applied, because our model does not need the user-specified threshold of minimum support. Experiment results indicate that the recommended algorithm can powerfully generate non-redundant fuzzy multilevel association rules.
多等级电动汽车充电站的选址与算法%Location and algorithm of multi-level electric vehicle charging stations
Institute of Scientific and Technical Information of China (English)
张国亮; 李波; 王运发
2011-01-01
作为电动汽车运营所必须的基础配套服务设施,充电站的建设位置与规模对推广电动汽车有着重要的意义。提出了一个多等级电动汽车充电站的选址与求解算法,考虑电动汽车用户分布的特性,基于目标规划思想,建立了使得充电站初始建设成本及用户充电总成本最小化的多等级充电站选址模型。为求解该模型,发展了一个改进的禁忌搜索算法。针对其中表示站址等级和相关用户分配的两个决策变量,设计了禁忌编码和初始解构建相结合的新颖设计方案,并采用2-opt邻域搜索策略,可同时确定出充电站的建址位置、建设的等级及各个需求点的分配。最后通过仿真算例表明,该算法具有很好的站址寻优能力及收敛性能,验证了本文提出的模型的有效性。%The charging station is part of the crucial infrastructure of the electric vehicle,and the location and scale of the charging stations are significant for the development of the electric vehicle industry.A location and solving algorithm of multi-level electric vehicle charging stations was proposed.Concerning the user＇ distributions,based on the objective program thought,the multi-level electric site model was developed to minimize the initial construction cost and the total users＇ charging service cost.An improved tabu search algorithm was presented to solve the model.The new combination of tabu coding and the generating of initial solutions were designed to characterize the two decision variables of the multi-level sites and the allocation to the users,using the strategy of 2-opt search neighbor,locating sites,station levels and the allocation of the demand points to the stations were simultaneously determined.Finally,a numerical example demonstrated that the algorithm had better global searching performance and convergence property and the proposed model was also effective.
Improved Chaff Solution Algorithm
2009-03-01
Programme de démonstration de technologies (PDT) sur l’intégration de capteurs et de systèmes d’armes embarqués (SISWS), un algorithme a été élaboré...technologies (PDT) sur l’intégration de capteurs et de systèmes d’armes embarqués (SISWS), un algorithme a été élaboré pour déterminer automatiquement...0Z4 2. SECURITY CLASSIFICATION (Overall security classification of the document including special warning terms if applicable .) UNCLASSIFIED
Liu, Peng; Wang, Qiong; Niu, Meixing; Wang, Dunyou
2017-08-10
Combining multi-level quantum mechanics theories and molecular mechanics with an explicit water model, we investigated the ring opening process of guanine damage by hydroxyl radical in aqueous solution. The detailed, atomic-level ring-opening mechanism along the reaction pathway was revealed in aqueous solution at the CCSD(T)/MM levels of theory. The potentials of mean force in aqueous solution were calculated at both the DFT/MM and CCSD(T)/MM levels of the theory. Our study found that the aqueous solution has a significant effect on this reaction in solution. In particular, by comparing the geometries of the stationary points between in gas phase and in aqueous solution, we found that the aqueous solution has a tremendous impact on the torsion angles much more than on the bond lengths and bending angles. Our calculated free-energy barrier height 31.6 kcal/mol at the CCSD(T)/MM level of theory agrees well with the one obtained based on gas-phase reaction profile and free energies of solvation. In addition, the reaction path in gas phase was also mapped using multi-level quantum mechanics theories, which shows a reaction barrier at 19.2 kcal/mol at the CCSD(T) level of theory, agreeing very well with a recent ab initio calculation result at 20.8 kcal/mol.
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Ykhlef Faycal
2010-01-01
Full Text Available Problem statement: : The objective of prosody modification is to change the amplitude, duration and pitch (F0 of speech segments without altering their spectral envelop. Applications are numerous, including, Text-To-Speech synthesis, transformation of voice characteristics and foreign language learning. Several approaches have been developed in the literature to achieve this goal. The main restrictions of these latter are in the modification range, the synthesized speech quality and naturalness of spoken language. The latest research studies provide evidence that the first Formant (F1 and F0 are dependent; suggesting that in order to preserve high quality and naturalness of the speech signal, any change to one of these parameters must be accompanied by a suitable modification of the other. Approach: This study introduced a prosody modification method using combining Synchronous Overlap and Add with Fixed-Synthesis (SOLAFS algorithm and a multi level decomposition based on Discrete Wavelet Transform (DWT to overcome the limitations cited above. It used Standard Arabic (SA sounds. For a purpose of comparison, two techniques based on frame by frame processing were proposed. The first one consists in a pitch synchronous processing of the mth approximation level time segments used in SOLAFS algorithm. It was aimed to modify the prosody of the input speech without affecting the spectral envelop. The second one explores the correlation between F1 and F0 in the corresponding approximation level of SA sounded and modified duration and both F0 and F1 scales. It was based on a re-sampling method using FFT interpolation. The use of multi level analysis was aimed to provide independent control over the spectral envelope. In both techniques, the decomposition level depends on the chosen sampling Frequency (FS. F0 marking was based on multi level peaks comparison. Both techniques use an automatic speech classification algorithm based on modified version of the
Chang, Ting-Kuo; Hsu, Ching-Chi; Chen, Kuan-Ting
2015-01-01
Anterior cervical discectomy and fusion is a common surgical procedure performed to remove a degenerative or herniated disc in cervical spine. Unfortunately, clinical complications of anterior cervical plate (ACP) systems still occur, such as weak fixation stability and implant loosening. Previous researchers have attempted to ameliorate these complications by varying screw orientations, but the screw orientations are mainly determined according to the investigator's experiences. Thus, the aim of this study was to discover the optimal screw orientations of ACP systems to achieve acceptable fixation stability using finite element simulations and engineering algorithms. Three-dimensional finite element models of C3-T2 multi-level segments with an ACP system were first developed to analyze the fixation stability using ANSYS Workbench 14.5. Then, artificial neural networks were applied to create one objective function, and the optimal screw orientations of an ACP system were discovered by genetic algorithms. Finally, the numerical models and the optimization study were validated using biomechanical tests. The results showed that the optimal design of the ACP system had highest fixation stability compared with other ACP designs. The neuro-genetic algorithm has effectively reduced the time and effort required for discovering for the optimal screw orientations of an ACP system. The optimum screw orientation of the ACP system could be successfully discovered, and it revealed excellent fixation stability for the treatment of cervical degenerative disc disease. This study could directly provide the biomechanical rationale and surgical suggestion to orthopedic surgeons.
On the Multilevel Solution Algorithm for Markov Chains
Horton, Graham
1997-01-01
We discuss the recently introduced multilevel algorithm for the steady-state solution of Markov chains. The method is based on an aggregation principle which is well established in the literature and features a multiplicative coarse-level correction. Recursive application of the aggregation principle, which uses an operator-dependent coarsening, yields a multi-level method which has been shown experimentally to give results significantly faster than the typical methods currently in use. When cast as a multigrid-like method, the algorithm is seen to be a Galerkin-Full Approximation Scheme with a solution-dependent prolongation operator. Special properties of this prolongation lead to the cancellation of the computationally intensive terms of the coarse-level equations.
Stigt, van Rien; Driessen, Peter P.J.; Spit, Tejo
2016-01-01
Devolution is advocated as a solution to scale mismatches in urban environmental governance. However, urban environmental quality is a multi-scalar issue: its various aspects – noise, soil, odour, air, water et cetera – are influenced by processes at multiple spatial and temporal scales. Decisions b
Lv, Jing; Zhang, Jingxue; Wang, Dunyou
2016-02-17
We employed a multi-level quantum mechanics and molecular mechanics approach to study the reaction NH2Cl + OH(-) in aqueous solution. The multi-level quantum method (including the DFT method with both the B3LYP and M06-2X exchange-correlation functionals and the CCSD(T) method, and both methods with the aug-cc-pVDZ basis set) was used to treat the quantum reaction region in different stages of the calculation in order to obtain an accurate potential of mean force. The obtained free energy activation barriers at the DFT/MM level of theory yielded a big difference of 21.8 kcal mol(-1) with the B3LYP functional and 27.4 kcal mol(-1) with the M06-2X functional respectively. Nonetheless, the barrier heights become very close when shifted from DFT to CCSD(T): 22.4 kcal mol(-1) and 22.9 kcal mol(-1) at CCSD(T)(B3LYP)/MM and CCSD(T)(M06-2X)/MM levels of theory, respectively. The free reaction energy obtained using CCSD(T)(M06-2X)/MM shows an excellent agreement with the one calculated using the available gas-phase data. Aqueous solution plays a significant role in shaping the reaction profile. In total, the water solution contributes 13.3 kcal mol(-1) and 14.6 kcal mol(-1) to the free energy barrier heights at CCSD(T)(B3LYP)/MM and CCSD(T)(M06-2X)/MM respectively. The title reaction at nitrogen is a faster reaction than the corresponding reaction at carbon, CH3Cl + OH(-).
Atak, Onur; Huybrechs, Daan; Pluymers, Bert; Desmet, Wim
2014-07-01
Sonic crystals can be used as acoustic lenses in certain frequencies and the design of such systems by creating vacancies and using genetic algorithms has been proven to be an effective method. So far, rigid cylinders have been used to create such acoustic lens designs. On the other hand, it has been proven that Helmholtz resonators can be used to construct acoustic lenses with higher refraction index as compared to rigid cylinders, especially in low frequencies by utilizing their local resonances. In this paper, these two concepts are combined to design acoustic lenses that are based on Helmholtz resonators. The Multi-Level Wave Based Method is used as the prediction method. The benefits of the method in the context of design procedure are demonstrated. In addition, symmetric boundary conditions are derived for more efficient calculations. The acoustic lens designs that use Helmholtz resonators are compared with the acoustic lens designs that use rigid cylinders. It is shown that using Helmholtz resonator based sonic crystals leads to better acoustic lens designs, especially at the low frequencies where the local resonances are pronounced.
Liu, Peng; Zhang, Jingxue; Wang, Dunyou
2017-06-07
A double-inversion mechanism of the F(-) + CH3I reaction was discovered in aqueous solution using combined multi-level quantum mechanics theories and molecular mechanics. The stationary points along the reaction path show very different structures to the ones in the gas phase due to the interactions between the solvent and solute, especially strong hydrogen bonds. An intermediate complex, a minimum on the potential of mean force, was found to serve as a connecting-link between the abstraction-induced inversion transition state and the Walden-inversion transition state. The potentials of mean force were calculated with both the DFT/MM and CCSD(T)/MM levels of theory. Our calculated free energy barrier of the abstraction-induced inversion is 69.5 kcal mol(-1) at the CCSD(T)/MM level of theory, which agrees with the one at 72.9 kcal mol(-1) calculated using the Born solvation model and gas-phase data; and our calculated free energy barrier of the Walden inversion is 24.2 kcal mol(-1), which agrees very well with the experimental value at 25.2 kcal mol(-1) in aqueous solution. The calculations show that the aqueous solution makes significant contributions to the potentials of mean force and exerts a big impact on the molecular-level evolution along the reaction pathway.
Discrete Riccati equation solutions: Distributed algorithms
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D. G. Lainiotis
1996-01-01
Full Text Available In this paper new distributed algorithms for the solution of the discrete Riccati equation are introduced. The algorithms are used to provide robust and computational efficient solutions to the discrete Riccati equation. The proposed distributed algorithms are theoretically interesting and computationally attractive.
A Multi-Step and Multi-Level Approach for Computer Aided Molecular Design
DEFF Research Database (Denmark)
Harper, Peter Mathias; Gani, Rafiqul
2001-01-01
. The problem formulation step incorporates a knowledge base for the identification and setup of the design criteria. Candidate compounds are identified using a multi-level generate and test CAMD solution algorithm capable of designing molecules having a high level of molecular detail. A post solution step...
Game tree algorithms and solution trees
W.H.L.M. Pijls (Wim); A. de Bruin (Arie)
1998-01-01
textabstractIn this paper, a theory of game tree algorithms is presented, entirely based upon the concept of solution tree. Two types of solution trees are distinguished: max and min trees. Every game tree algorithm tries to prune nodes as many as possible from the game tree. A cut-off criterion in
Multi-level decision making models, methods and applications
Zhang, Guangquan; Gao, Ya
2015-01-01
This monograph presents new developments in multi-level decision-making theory, technique and method in both modeling and solution issues. It especially presents how a decision support system can support managers in reaching a solution to a multi-level decision problem in practice. This monograph combines decision theories, methods, algorithms and applications effectively. It discusses in detail the models and solution algorithms of each issue of bi-level and tri-level decision-making, such as multi-leaders, multi-followers, multi-objectives, rule-set-based, and fuzzy parameters. Potential readers include organizational managers and practicing professionals, who can use the methods and software provided to solve their real decision problems; PhD students and researchers in the areas of bi-level and multi-level decision-making and decision support systems; students at an advanced undergraduate, master’s level in information systems, business administration, or the application of computer science.
Directory of Open Access Journals (Sweden)
Constanta Nicoleta BODEA
2008-01-01
Full Text Available Is an original paper, which contains a hierarchical model with three levels, for determining the linearized non-homogeneous and homogeneous credibility premiums at company level, at sector level and at contract level, founded on the relevant covariance relations between the risk premium, the observations and the weighted averages. We give a rather explicit description of the input data for the multi- level hierarchical model used, only to show that in practical situations, there will always be enough data to apply credibility theory to a real insurance portfolio.
Indian Academy of Sciences (India)
Sangeetha S; S Jeevananthan
2015-12-01
Genetic Algorithms (GA) has always done justice to the art of optimization. One such endeavor has been made in employing the roots of GA in a most proficient way to determine the switching moments of a cascaded H-bridge seven level inverter with equal DC sources. Evolutionary techniques have proved themselves efficient to solve such an obscurity. GA is one of the methods to achieve the objective through biological mimicking. The extraordinary property of crossover is extracted using Random 3-Point Neighbourhood Crossover (RPNC) and Multi Midpoint Selective Bit Neighbourhood crossover (MMSBNC). This paper deals with solving of the selective harmonic equations (SHE) using binary coded GA specific to knowledge based neighbourhood multipoint crossover technique. This is directly related to the switching moments of the multilevel inverter under consideration. Although the previous root-finding techniques such as N-R or resultant like methods endeavor the same, the latter offers faster convergence, better program reliability and wide range of solutions. With an acute algorithm developed in Turbo C, the switching moments are calculated offline. The simulation results closely agree with the hardware results.
A new algorithm for anisotropic solutions
Indian Academy of Sciences (India)
M Chaisi; S D Maharaj
2006-02-01
We establish a new algorithm that generates a new solution to the Einstein field equations, with an anisotropic matter distribution, from a seed isotropic solution. The new solution is expressed in terms of integrals of an isotropic gravitational potential; and the integration can be completed exactly for particular isotropic seed metrics. A good feature of our approach is that the anisotropic solutions necessarily have an isotropic limit. We find two examples of anisotropic solutions which generalise the isothermal sphere and the Schwarzschild interior sphere. Both examples are expressed in closed form involving elementary functions only.
Efficient Solution Algorithms for Factored MDPs
Guestrin, C; Parr, R; Venkataraman, S; 10.1613/jair.1000
2011-01-01
This paper addresses the problem of planning under uncertainty in large Markov Decision Processes (MDPs). Factored MDPs represent a complex state space using state variables and the transition model using a dynamic Bayesian network. This representation often allows an exponential reduction in the representation size of structured MDPs, but the complexity of exact solution algorithms for such MDPs can grow exponentially in the representation size. In this paper, we present two approximate solution algorithms that exploit structure in factored MDPs. Both use an approximate value function represented as a linear combination of basis functions, where each basis function involves only a small subset of the domain variables. A key contribution of this paper is that it shows how the basic operations of both algorithms can be performed efficiently in closed form, by exploiting both additive and context-specific structure in a factored MDP. A central element of our algorithms is a novel linear program decomposition te...
Multi-Level Audio Classification Architecture
Directory of Open Access Journals (Sweden)
Jozef Vavrek
2015-01-01
Full Text Available A multi-level classification architecture for solving binary discrimination problem is proposed in this paper. The main idea of proposed solution is derived from the fact that solving one binary discrimination problem multiple times can reduce the overall miss-classification error. We aimed our effort towards building the classification architecture employing the combination of multiple binary SVM (Support Vector Machine classifiers for solving two-class discrimination problem. Therefore, we developed a binary discrimination architecture employing the SVM classifier (BDASVM with intention to use it for classification of broadcast news (BN audio data. The fundamental element of BDASVM is the binary decision (BD algorithm that performs discrimination between each pair of acoustic classes utilizing decision function modeled by separating hyperplane. The overall classification accuracy is conditioned by finding the optimal parameters for discrimination function resulting in higher computational complexity. The final form of proposed BDASVM is created by combining four BDSVM discriminators supplemented by decision table. Experimental results show that the proposed classification architecture can decrease the overall classification error in comparison with binary decision trees SVM (BDTSVM architecture.
Directory of Open Access Journals (Sweden)
P. Avirajamanjula
2015-03-01
Full Text Available Multilevel Inverters (MLIs have drawn increasing attention in numerous applications, especially in drives, distributed energy resources area, utility etc. MLIs have the ability to synthesize a near sinusoidal output voltage wave with minimal Total Harmonic Distortion (THD in low frequency switching. Even though they offer lower THD, the presence of lower order harmonics is objectionable and harmonics elimination in Multilevel Inverters (MLIs has been receiving immense attention for the past few decades. Existing Selective Harmonic Elimination (SHE techniques can eliminate the objectionable lower order voltage harmonics with low switching frequency by solving the Fourier non-linear transcendental equations of the output voltage. The line current harmonics has a direct role to play on the magneto-motive force and results in increase of mismatching of air-gap permeance, vibrations, acoustic noise etc. This study proposes Normalized Least Mean Squares (NLMS algorithm based scheme to eliminate the selected dominant harmonics in load current using only the knowledge of the frequencies to be eliminated. The algorithm is simulated using MATLAB/SIMULINK tool for a three-phase VSI to eliminate the fifth and seventh harmonics. The informative simulation results verify the validity and effectiveness of the proposed algorithm. The system performance is analyzed based on the simulation results considering Total Harmonic Distortion (THD, magnitude of eliminated harmonics and frequency spectrum.
Energy Technology Data Exchange (ETDEWEB)
DuPont, Bryony; Cagan, Jonathan; Moriarty, Patrick
2016-07-01
This paper presents a system of modeling advances that can be applied in the computational optimization of wind plants. These modeling advances include accurate cost and power modeling, partial wake interaction, and the effects of varying atmospheric stability. To validate the use of this advanced modeling system, it is employed within an Extended Pattern Search (EPS)-Multi-Agent System (MAS) optimization approach for multiple wind scenarios. The wind farm layout optimization problem involves optimizing the position and size of wind turbines such that the aerodynamic effects of upstream turbines are reduced, which increases the effective wind speed and resultant power at each turbine. The EPS-MAS optimization algorithm employs a profit objective, and an overarching search determines individual turbine positions, with a concurrent EPS-MAS determining the optimal hub height and rotor diameter for each turbine. Two wind cases are considered: (1) constant, unidirectional wind, and (2) three discrete wind speeds and varying wind directions, each of which have a probability of occurrence. Results show the advantages of applying the series of advanced models compared to previous application of an EPS with less advanced models to wind farm layout optimization, and imply best practices for computational optimization of wind farms with improved accuracy.
Algebraic dynamics solution and algebraic dynamics algorithm of Burgers equations
Institute of Scientific and Technical Information of China (English)
2008-01-01
Algebraic dynamics solution and algebraic dynamics algorithm of nonlinear partial differential evolution equations in the functional space are applied to Burgers equation. The results indicate that the approach is effective for analytical solutions to Burgers equation, and the algorithm for numerical solutions of Burgers equation is more stable, with higher precision than other existing finite difference algo-rithms.
Iordache, Octavian
2011-01-01
This book is devoted to modeling of multi-level complex systems, a challenging domain for engineers, researchers and entrepreneurs, confronted with the transition from learning and adaptability to evolvability and autonomy for technologies, devices and problem solving methods. Chapter 1 introduces the multi-scale and multi-level systems and highlights their presence in different domains of science and technology. Methodologies as, random systems, non-Archimedean analysis, category theory and specific techniques as model categorification and integrative closure, are presented in chapter 2. Chapters 3 and 4 describe polystochastic models, PSM, and their developments. Categorical formulation of integrative closure offers the general PSM framework which serves as a flexible guideline for a large variety of multi-level modeling problems. Focusing on chemical engineering, pharmaceutical and environmental case studies, the chapters 5 to 8 analyze mixing, turbulent dispersion and entropy production for multi-scale sy...
Institute of Scientific and Technical Information of China (English)
苏志同; 王升; 李少华
2012-01-01
本文主要是针对在关联分析领域，多层关联分析算法中对事务集中连续数据的层次划分算法进行相关的研究与探讨。论述了不同数值型数据分层方法的利弊，同时提出了基于信息熵的数值型数据概念分层算法，验证了该算法在提高有效频繁项集数上相对于其他分层算法具有一定的优势。%This articleis mainlyrelated tothefieldofcorrelation analysis, and it focuses on dis cussing and researching continuous datatransaction-level partitioning algorithm in multi-level associationanalysis algorithms. Discussingthe pros and consofdifferentnumeric datalayered a pproach, and proposingthenumerical datahierarchicalalgorithm based on information entropyc oncept , andverifying that thealgorithmhas certain advantagesto improvethenumberofeffective frequentitems comparing tootherhierarchicalalgorithms.
一种多层次的云平台安全解决方案%A multi-level cloud platform security solution
Institute of Scientific and Technical Information of China (English)
董振江; 王雪; 胡洁; 华宇
2013-01-01
This solution is divided into several levels, which are container-level security, virtual machine-level security, network-level security. This paper focuses on solutions for PaaS Cloud platform, and makes the analysis of three aspects, which are the application security inside of the container, the container's own security, the intrusion prevention security outside of the container.%论述了云平台的整体安全解决方案.该方案分为应用级别安全、容器级别安全、网络级别安全等层次.着重阐述了针对PaaS云平台的解决方案,从容器内部应用安全、容器自身安全、容器外部的入侵防御安全三个方面做出了分析.
Institute of Scientific and Technical Information of China (English)
左龙; 彭小奇; 钟云飞; 彭曦; 唐英
2013-01-01
为了提高基于大容量指纹库的自动指纹识别系统的检索效率,提出一种基于独立分类特征的指纹多级分类算法.依据评测指标对输入指纹图像进行质量评估,若指纹质量不合格,则提醒用户重新输入；若指纹质量合格,则分别利用指纹图像的纹型类别,奇异点间脊线数、中心区域脊线平均频率3个相互独立的分类特征实现多级分类,从而逐级减小检索空间.实验结果表明,该分类算法检索效率高、鲁棒性强,为大容量指纹库提供了一种快速有效的索引机制,具有很强的实用性.%In order to improve retrieval efficiency of the automated fingerprint identification system for large-scale fingerprint database, a multi-level fingerprint classification algorithm based on independent classification features is proposed. Quality evaluation indexes could be applied to evaluate the quality of input fingerprints, remind the users to re-enter fingerprints if the quality is poor. For the good quality fingerprints, three independent features including grain type, number of ridges between singular points and average frequency of ridge line in central region are separately used to realise multi-level classification, which could decrease the retrieval space gradually. Experimental results show, the proposed classification algorithm has high retrieval efficiency and strong robustness, which provides a rapid and effective index mechanism for large-scale fingerprint database. It has good practicality.
Institute of Scientific and Technical Information of China (English)
胡中栋; 谢金伟
2014-01-01
应用遗传算法对车辆路径问题（VRP）求解时，由于遗传算法在解决VRP问题时，交叉操作难以保留优秀基因片段，可能导致算法收敛较慢等问题。在一定程度上影响了遗传算法解决VRP问题的实用性。在前人的基础上，通过一种多级正向变异方法，使变异最大程度向好的方向进行，拆除基因片段中较差的基因连接并建立新基因连接，从而得到较优的新基因片段，重复一定的变异次数，让变异达到最优效果。通过实验表明多级正向变异明显提高了遗传算法解决此类问题的效率。%When using genetic algorithm to solve VRP problem, a slower convergence problem may be generated because the crossover operation could not keep good genes, which affects the usefulness of genetic algorithms to solve the VRP problem to a certain extent. On the basis of our predecessors, we have created a multi-level forward mutation method which dismantles poor gene fragment connection and creates a new connection to get a better gene. A large number of experiments show that forward mutation can greatly improve the genetic algorithm to solve such problems efficiently.
Optimization of simulated moving bed (SMB) chromatography: a multi-level optimization procedure
DEFF Research Database (Denmark)
Jørgensen, Sten Bay; Lim, Young-il
2004-01-01
This paper presents a multi-level optimization strategy to obtain optimum operating conditions (four flowrates and cycle time) of nonlinear simulated moving bed chromatography. The multi-level optimization procedure (MLOP) approaches systematically from initialization to optimization with two...... objective functions (productivity and desorbent consumption), employing the standing wave analysis, the true moving bed (TMB) model and the simulated moving bed (SMB) model. The procedure is constructed on a non-worse solution property advancing level by level and its solution does not mean a global optimum....... That is, the lower desorbent consumption under the higher productivity is successively obtained on the basis of the SMB model, as the two SMB-model optimizations are repeated using a standard SQP (successive quadratic programming) algorithm. This approach takes advantage of the TMB model and surmounts...
Unconventional Coding Technique Applied to Multi-Level Polarization Modulation
Rutigliano, G. G.; Betti, S.; Perrone, P.
2016-05-01
A new technique is proposed to improve information confidentiality in optical-fiber communications without bandwidth consumption. A pseudorandom vectorial sequence was generated by a dynamic system algorithm and used to codify a multi-level polarization modulation based on the Stokes vector. Optical-fiber birefringence, usually considered as a disturbance, was exploited to obfuscate the signal transmission. At the receiver end, the same pseudorandom sequence was generated and used to decode the multi-level polarization modulated signal. The proposed scheme, working at the physical layer, provides strong information security without introducing complex processing and thus latency.
Massively Parallel Algorithms for Solution of Schrodinger Equation
Fijany, Amir; Barhen, Jacob; Toomerian, Nikzad
1994-01-01
In this paper massively parallel algorithms for solution of Schrodinger equation are developed. Our results clearly indicate that the Crank-Nicolson method, in addition to its excellent numerical properties, is also highly suitable for massively parallel computation.
SOLUTION OF THE SATELLITE TRANSFER PROBLEM WITH HYBRID MEMETIC ALGORITHM
Directory of Open Access Journals (Sweden)
A. V. Panteleyev
2014-01-01
Full Text Available This paper presents a hybrid memetic algorithm (MA to solve the problem of finding the optimal program control of nonlinear continuous deterministic systems based on the concept of the meme, which is one of the promising solutions obtained in the course of implementing the procedure for searching the extremes. On the basis of the proposed algorithm the software complex is formed in C#. The solution of satellite transfer problem is presented.
Handbook on multi-level governance
2010-01-01
Scholarship of multi-level governance has developed into one of the most innovative themes of research in political science and public policy. This accessible Handbook presents a thorough review of the wide-ranging literature, encompassing various theoretical and conceptual approaches to multi-level governance and their application to policy-making in domestic, regional and global contexts. The importance of multi-level governance in specific policy areas is highlighted, and the contribut...
Biodiversity optimal sampling: an algorithmic solution
Directory of Open Access Journals (Sweden)
Alessandro Ferrarini
2012-03-01
Full Text Available Biodiversity sampling is a very serious task. When biodiversity sampling is not representative of the biodiversity spatial pattern due to few data or uncorrected sampling point locations, successive analyses, models and simulations are inevitably biased. In this work, I propose a new solution to the problem of biodiversity sampling. The proposed approach is proficient for habitats, plant and animal species, in addition it is able to answer the two pivotal questions of biodiversity sampling: 1 how many sampling points and 2 where are the sampling points.
Multi level configuration of ETO products
DEFF Research Database (Denmark)
Petersen, Thomas Ditlev; Jørgensen, Kaj Asbjørn; Hvolby, Hans-Henrik
2007-01-01
The paper introduces and defines central concepts related to multi level configuration and analyzes which challenges an engineer to order company must deal with to be able to realize a multi level configuration system. It is argued that high flexibility can be achieved and focus can be directed i...
A solution quality assessment method for swarm intelligence optimization algorithms.
Zhang, Zhaojun; Wang, Gai-Ge; Zou, Kuansheng; Zhang, Jianhua
2014-01-01
Nowadays, swarm intelligence optimization has become an important optimization tool and wildly used in many fields of application. In contrast to many successful applications, the theoretical foundation is rather weak. Therefore, there are still many problems to be solved. One problem is how to quantify the performance of algorithm in finite time, that is, how to evaluate the solution quality got by algorithm for practical problems. It greatly limits the application in practical problems. A solution quality assessment method for intelligent optimization is proposed in this paper. It is an experimental analysis method based on the analysis of search space and characteristic of algorithm itself. Instead of "value performance," the "ordinal performance" is used as evaluation criteria in this method. The feasible solutions were clustered according to distance to divide solution samples into several parts. Then, solution space and "good enough" set can be decomposed based on the clustering results. Last, using relative knowledge of statistics, the evaluation result can be got. To validate the proposed method, some intelligent algorithms such as ant colony optimization (ACO), particle swarm optimization (PSO), and artificial fish swarm algorithm (AFS) were taken to solve traveling salesman problem. Computational results indicate the feasibility of proposed method.
Cashier Problem: a Greedy Algorithm and an optimal Solution
Directory of Open Access Journals (Sweden)
Nicolae GIURGITEANU
2006-01-01
Full Text Available We will remind briefly the cashier problem. A cashier has leeway a range of different fractional coins and has to pay a certain amount using the most reduced number of coins. If we mark the pay-desk monetary with P {p ,..., pn } 1 = , each pi having as denomination di and with A the final sum, the cashier must determine a coins subset { } m S q ,..., q 1 = of P, so that i m i id q A Σ==1. In order to solve this problem, there are several solutions consisting in greedy algorithms. Although there is an optimal solution, in the present article we will highlight a greedy algorithm and an optimal solution for this problem. The solution known at the time being use a lot of memory and, in addition, is difficult to justify, occurring the risk of misunderstanding by the reader. Our solution is simpler and uses little memory
MULTI LEVEL ENCRYPTION APPROACH TO SECURE CLOUD DATA
Mukesh Kumar Jha*, Veerendra Shrivastava
2016-01-01
Now A Days cloud computing become an extensive area of research where data and resource are sharing among the various user through public cloud .However protecting data and resources on cloud is a challenging issue. In the previous HDFS approach when HDFS file system need to secure this is create additional complicity of algorithm. To address this issue and ensuring data security in cloud storage we propose “MESCD” (Multi Level Encryption approach to secure cloud data) has been proposed. In t...
A Multi-step and Multi-level approach for Computer Aided Molecular Design
DEFF Research Database (Denmark)
A general multi-step approach for setting up, solving and solution analysis of computer aided molecular design (CAMD) problems is presented. The approach differs from previous work within the field of CAMD since it also addresses the need for a computer aided problem formulation and result analysis....... The problem formulation step incorporates a knowledge base for the identification and setup of the design criteria. Candidate compounds are identified using a multi-level generate and test CAMD solution algorithm capable of designing molecules having a high level of molecular detail. A post solution step...... using an Integrated Computer Aided System (ICAS) for result analysis and verification is included in the methodology. Keywords: CAMD, separation processes, knowledge base, molecular design, solvent selection, substitution, group contribution, property prediction, ICAS Introduction The use of Computer...
Multi-level methods and approximating distribution functions
Wilson, D.; Baker, R. E.
2016-07-01
Biochemical reaction networks are often modelled using discrete-state, continuous-time Markov chains. System statistics of these Markov chains usually cannot be calculated analytically and therefore estimates must be generated via simulation techniques. There is a well documented class of simulation techniques known as exact stochastic simulation algorithms, an example of which is Gillespie's direct method. These algorithms often come with high computational costs, therefore approximate stochastic simulation algorithms such as the tau-leap method are used. However, in order to minimise the bias in the estimates generated using them, a relatively small value of tau is needed, rendering the computational costs comparable to Gillespie's direct method. The multi-level Monte Carlo method (Anderson and Higham, Multiscale Model. Simul. 10:146-179, 2012) provides a reduction in computational costs whilst minimising or even eliminating the bias in the estimates of system statistics. This is achieved by first crudely approximating required statistics with many sample paths of low accuracy. Then correction terms are added until a required level of accuracy is reached. Recent literature has primarily focussed on implementing the multi-level method efficiently to estimate a single system statistic. However, it is clearly also of interest to be able to approximate entire probability distributions of species counts. We present two novel methods that combine known techniques for distribution reconstruction with the multi-level method. We demonstrate the potential of our methods using a number of examples.
New multi-level codes over GF(q)
Wu, Jiantian; Costello, Daniel J., Jr.
1990-01-01
Set partitioning to multi-dimensional signal spaces over GF(q), particularly GF sup q-1(q) and GF sup q (q), and show how to construct both multi-level block codes and multi-level trellis codes over GF(q). Two classes of multi-level (n, k, d) block codes over GF(q) with block length n, number of information symbols k, and minimum distance d sub min greater than or = d, are presented. These two classes of codes use Reed-Solomon codes as component codes. They can be easily decoded as block length q-1 Reed-Solomon codes or block length q or q + 1 extended Reed-Solomon codes using multi-stage decoding. Many of these codes have larger distances than comparable q-ary block codes, as component codes. Low rate q-ary convolutional codes, work error correcting convolutional codes, and binary-to-q-ary convolutional codes can also be used to construct multi-level trellis codes over GF(q) or binary-to-q-ary trellis codes, some of which have better performance than the above block codes. All of the new codes have simple decoding algorithms based on hard decision multi-stage decoding.
Combinatorial optimization problem solution based on improved genetic algorithm
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.
Energy Hole Solution Algorithm in Wireless Sensor Network
Directory of Open Access Journals (Sweden)
Yuting Lu
2014-04-01
Full Text Available Since the sensor nodes near the Sink take more communication load leading to excessive energy consumption and short its life cycle, this paper proposes a new energy hole solution algorithm. The algorithm adds some long chain to the Sink node to relieve energy hole of reducing data forwarding number around the Sink node, so as to prolong the lifecycle of the network. Firstly, The algorithm carries out the analysis of energy consumption to equidistance transmission network and puts forward adopting tactics of small world to alleviate energy hole and analyzes the position and number of long chain’ influence on energy consumption and the network life cycle. Finally, the thesis carries out the simulation experiment. The experimental results show that this algorithm can significantly improve the network lifetime and easy to implement in practice.
Naturally selecting solutions: the use of genetic algorithms in bioinformatics.
Manning, Timmy; Sleator, Roy D; Walsh, Paul
2013-01-01
For decades, computer scientists have looked to nature for biologically inspired solutions to computational problems; ranging from robotic control to scheduling optimization. Paradoxically, as we move deeper into the post-genomics era, the reverse is occurring, as biologists and bioinformaticians look to computational techniques, to solve a variety of biological problems. One of the most common biologically inspired techniques are genetic algorithms (GAs), which take the Darwinian concept of natural selection as the driving force behind systems for solving real world problems, including those in the bioinformatics domain. Herein, we provide an overview of genetic algorithms and survey some of the most recent applications of this approach to bioinformatics based problems.
Multi-level systems modeling and optimization for novel aircraft
Subramanian, Shreyas Vathul
This research combines the disciplines of system-of-systems (SoS) modeling, platform-based design, optimization and evolving design spaces to achieve a novel capability for designing solutions to key aeronautical mission challenges. A central innovation in this approach is the confluence of multi-level modeling (from sub-systems to the aircraft system to aeronautical system-of-systems) in a way that coordinates the appropriate problem formulations at each level and enables parametric search in design libraries for solutions that satisfy level-specific objectives. The work here addresses the topic of SoS optimization and discusses problem formulation, solution strategy, the need for new algorithms that address special features of this problem type, and also demonstrates these concepts using two example application problems - a surveillance UAV swarm problem, and the design of noise optimal aircraft and approach procedures. This topic is critical since most new capabilities in aeronautics will be provided not just by a single air vehicle, but by aeronautical Systems of Systems (SoS). At the same time, many new aircraft concepts are pressing the boundaries of cyber-physical complexity through the myriad of dynamic and adaptive sub-systems that are rising up the TRL (Technology Readiness Level) scale. This compositional approach is envisioned to be active at three levels: validated sub-systems are integrated to form conceptual aircraft, which are further connected with others to perform a challenging mission capability at the SoS level. While these multiple levels represent layers of physical abstraction, each discipline is associated with tools of varying fidelity forming strata of 'analysis abstraction'. Further, the design (composition) will be guided by a suitable hierarchical complexity metric formulated for the management of complexity in both the problem (as part of the generative procedure and selection of fidelity level) and the product (i.e., is the mission
Multi-level Hybrid Cache: Impact and Feasibility
Energy Technology Data Exchange (ETDEWEB)
Zhang, Zhe [ORNL; Kim, Youngjae [ORNL; Ma, Xiaosong [ORNL; Shipman, Galen M [ORNL; Zhou, Yuanyuan [University of California, San Diego
2012-02-01
Storage class memories, including flash, has been attracting much attention as promising candidates fitting into in today's enterprise storage systems. In particular, since the cost and performance characteristics of flash are in-between those of DRAM and hard disks, it has been considered by many studies as an secondary caching layer underneath main memory cache. However, there has been a lack of studies of correlation and interdependency between DRAM and flash caching. This paper views this problem as a special form of multi-level caching, and tries to understand the benefits of this multi-level hybrid cache hierarchy. We reveal that significant costs could be saved by using Flash to reduce the size of DRAM cache, while maintaing the same performance. We also discuss design challenges of using flash in the caching hierarchy and present potential solutions.
Parallel hybrid algorithm for solution in electrical impedance equation
Ponomaryov, Volodymyr; Robles-Gonzalez, Marco; Bucio-Ramirez, Ariana; Ramirez-Tachiquin, Marco; Ramos-Diaz, Eduardo
2015-02-01
This work is dedicated to the analysis of the forward and the inverse problem to obtain a better approximation to the Electrical Impedance Tomography equation. In this case, we employ for the forward problem the numerical method based on the Taylor series in formal power and for the inverse problem the Finite Element Method. For the analysis of the forward problem, we proposed a novel algorithm, which employs a regularization technique for the stability, additionally the parallel computing is used to obtain the solution faster; this modification permits to obtain an efficient solution of the forward problem. Then, the found solution is used in the inverse problem for the approximation employing the Finite Element Method. The algorithms employed in this work are developed in structural programming paradigm in C++, including parallel processing; the time run analysis is performed only in the forward problem because the Finite Element Method due to their high recursive does not accept parallelism. Some examples are performed for this analysis, in which several conductivity functions are employed for two different cases: for the analytical cases: the exponential and sinusoidal functions are used, and for the geometrical cases the circle at center and five disk structure are revised as conductivity functions. The Lebesgue measure is used as metric for error estimation in the forward problem, meanwhile, in the inverse problem PSNR, SSIM, MSE criteria are applied, to determine the convergence of both methods.
Types of Multi-Level Governance
Directory of Open Access Journals (Sweden)
Gary Marks
2001-10-01
Full Text Available The reallocation of authority upwards, downwards, and sideways from central states has drawn attention from a growing number of scholars in the social sciences. Yet beyond the bedrock agreement that governance has become (and should be multi-level, there is no convergence about how it should be organized. This paper draws on various literatures in distinguishing two types of multi-level governance. One type conceives of dispersion of authority to multi-task, territorially mutually exclusive jurisdictions in a relatively stable system with limited jurisdictional levels and a limited number of units. A second type of governance pictures specialized, territorially overlapping jurisdictions in a relatively flexible, non-tiered system with a large number of jurisdictions. We find that both types co-exist in different locations, and we explain some facets of this co-existence.
Influence Maximization in Social Networks: Towards an Optimal Algorithmic Solution
Borgs, Christian; Chayes, Jennifer; Lucier, Brendan
2012-01-01
Diffusion is a fundamental graph process, underpinning such phenomena as epidemic disease contagion and the spread of innovation by word-of-mouth. We address the algorithmic problem of finding a set of k initial seed nodes in a network so that the expected size of the resulting cascade is maximized, under the standard independent cascade model of network diffusion. Our main result is an algorithm for the influence maximization problem that obtains the near-optimal approximation factor of (1 - 1/e - epsilon), for any epsilon > 0, in time O((m+n)log(n) / epsilon^3) where n and m are the number of vertices and edges in the network. Our algorithm is nearly runtime-optimal (up to a logarithmic factor) as we establish a lower bound of Omega(m+n) on the runtime required to obtain a constant approximation. Our method also allows a provable tradeoff between solution quality and runtime: we obtain an O(1/beta)-approximation in time O(n log^3(n) * a(G) / beta) for any beta > 1, where a(G) denotes the arboricity of the d...
ALGORITHM OF SELECTION EFFECTIVE SOLUTIONS FOR REPROFILING OF INDUSTRIAL BUILDINGS
Directory of Open Access Journals (Sweden)
MENEJLJUK A. I.
2016-08-01
Full Text Available Raising of problem.Non-compliance requirements of today's industrial enterprises, which were built during the Soviet period, as well as significant technical progress, economic reform and transition to market principles of performance evaluation leading to necessity to change their target and functionality. The technical condition of many industrial buildings in Ukraine allows to exploit them for decades.Redesigning manufacturing enterprises allows not only to reduce the cost of construction, but also to obtain new facilities in the city. Despite the large number of industrial buildings that have lost their effectiveness and relevance, as well as a significant investor interest in these objects, the scope of redevelopment in the construction remains unexplored. Analysis researches on the topic. The problem of reconstruction of industrial buildings considered in Topchy D. [3], Travin V. [9], as well as in the work of other scientists. However, there are no rules in regulatory documents and system studies for improving the organization of the reconstruction of buildings at realigning. The purpose of this work is the development an algorithm of actions for selection of effective organizational decisions at the planning stage of a reprofiling project of industrial buildings. The proposed algorithm allows you to select an effective organizational and technological solution for the re-profiling of industrial buildings, taking into account features of the building, its location, its state of structures and existing restrictions. The most effective organizational solution allows realize the reprofiling project of an industrial building in the most possible short terms and with the lowest possible use of material resources, taking into account the available features and restrictions. Conclusion. Each object has a number of unique features that necessary for considering at choosing an effective reprofiling variant. The developed algorithm for selecting
Multi-level SLIC superpixels segmentation method based on edge detection operator
Ni, Sen; Fu, Dongmei; Yang, Tao
2016-10-01
Simple linear iterative clustering (SLIC) super-pixel algorithm for its excellent performance and efficient border holding computational efficiency is widely used in image processing. But with the increase of the number of super-pixels, there will be a lot of redundancy in the image merging process. In this paper, we propose a multi-level super-pixels method based SLIC algorithm, which focuses on the target area to set up edge detection operator for generating multi-level super-pixels. Simulation results show that the proposed method ensures the accuracy of extraction and improves the computational efficiency.
An Algorithm for Solution of an Interval Valued EOQ Model
Directory of Open Access Journals (Sweden)
Susovan CHAKRABORTTY
2013-01-01
Full Text Available This paper deals with the problem of determining the economic order quantity (EOQin the interval sense. A purchasing inventory model with shortages and lead time, whose carryingcost, shortage cost, setup cost, demand quantity and lead time are considered as interval numbers,instead of real numbers. First, a brief survey of the existing works on comparing and ranking anytwo interval numbers on the real line is presented. A common algorithm for the optimum productionquantity (Economic lot-size per cycle of a single product (so as to minimize the total average cost isdeveloped which works well on interval number optimization under consideration. A numerical exampleis presented for better understanding the solution procedure. Finally a sensitive analysis of the optimalsolution with respect to the parameters of the model is examined.
Algebraic dynamics solution to and algebraic dynamics algorithm for nonlinear advection equation
Institute of Scientific and Technical Information of China (English)
2008-01-01
Algebraic dynamics approach and algebraic dynamics algorithm for the solution of nonlinear partial differential equations are applied to the nonlinear advection equa-tion. The results show that the approach is effective for the exact analytical solu-tion and the algorithm has higher precision than other existing algorithms in nu-merical computation for the nonlinear advection equation.
Multi level programming Paradigm for Extreme Computing
Petiton, S.; Sato, M.; Emad, N.; Calvin, C.; Tsuji, M.; Dandouna, M.
2014-06-01
Abstract: In order to propose a framework and programming paradigms for post-petascale computing, on the road to exascale computing and beyond, we introduced new languages, associated with a hierarchical multi-level programming paradigm, allowing scientific end-users and developers to program highly hierarchical architectures designed for extreme computing. In this paper, we explain the interest of such hierarchical multi-level programming paradigm for extreme computing and its well adaptation to several large computational science applications, such as for linear algebra solvers used for reactor core physic. We describe the YML language and framework allowing describing graphs of parallel components, which may be developed using PGAS-like language such as XMP, scheduled and computed on supercomputers. Then, we propose experimentations on supercomputers (such as the "K" and "Hooper" ones) of the hybrid method MERAM (Multiple Explicitly Restarted Arnoldi Method) as a case study for iterative methods manipulating sparse matrices, and the block Gauss-Jordan method as a case study for direct method manipulating dense matrices. We conclude proposing evolutions for this programming paradigm.
Multi-Level Languages are Generalized Arrows
Megacz, Adam
2010-01-01
The lambda calculus, subject to typing restrictions, provides a syntax for the internal language of cartesian closed categories. This paper establishes a parallel result: staging annotations, subject to named level restrictions, provide a syntax for the internal language of (the codomain of) a functor which preserves a premonoidal enrichment. Such functors are uniquely determined by functors from an {\\it enriching} category to an {\\it enriched} category. An equational axiomatization for the latter form is given, and Arrows are shown to constitute a special case. This result is most useful when the enrichment is that of a category of types and terms in a category of judgments. In such a scenario, the proof of correspondence yields a translation from well typed multi-level terms to well typed one-level terms which are parameterized over an instance of a {\\it generalized arrow} (GArrow). The translation is defined by induction on the structure of the proof that the multi-level program is well typed, relying on i...
Three essays on multi-level optimization models and applications
Rahdar, Mohammad
The general form of a multi-level mathematical programming problem is a set of nested optimization problems, in which each level controls a series of decision variables independently. However, the value of decision variables may also impact the objective function of other levels. A two-level model is called a bilevel model and can be considered as a Stackelberg game with a leader and a follower. The leader anticipates the response of the follower and optimizes its objective function, and then the follower reacts to the leader's action. The multi-level decision-making model has many real-world applications such as government decisions, energy policies, market economy, network design, etc. However, there is a lack of capable algorithms to solve medium and large scale these types of problems. The dissertation is devoted to both theoretical research and applications of multi-level mathematical programming models, which consists of three parts, each in a paper format. The first part studies the renewable energy portfolio under two major renewable energy policies. The potential competition for biomass for the growth of the renewable energy portfolio in the United States and other interactions between two policies over the next twenty years are investigated. This problem mainly has two levels of decision makers: the government/policy makers and biofuel producers/electricity generators/farmers. We focus on the lower-level problem to predict the amount of capacity expansions, fuel production, and power generation. In the second part, we address uncertainty over demand and lead time in a multi-stage mathematical programming problem. We propose a two-stage tri-level optimization model in the concept of rolling horizon approach to reducing the dimensionality of the multi-stage problem. In the third part of the dissertation, we introduce a new branch and bound algorithm to solve bilevel linear programming problems. The total time is reduced by solving a smaller relaxation
Perspectives on Multi-Level Dynamics
Atay, Fatihcan M; Blanchard, Philippe; Cessac, Bruno; Olbrich, Eckehard; Volchenkov, Dima
2016-01-01
As Physics did in previous centuries, there is currently a common dream of extracting generic laws of nature in economics, sociology, neuroscience, by focalising the description of phenomena to a minimal set of variables and parameters, linked together by causal equations of evolution whose structure may reveal hidden principles. This requires a huge reduction of dimensionality (number of degrees of freedom) and a change in the level of description. Beyond the mere necessity of developing accurate techniques affording this reduction, there is the question of the correspondence between the initial system and the reduced one. In this paper, we offer a perspective towards a common framework for discussing and understanding multi-level systems exhibiting structures at various spatial and temporal levels. We propose a common foundation and illustrate it with examples from different fields. We also point out the difficulties in constructing such a general setting and its limitations.
Directory of Open Access Journals (Sweden)
Abolfazl Kazemi
2015-02-01
Full Text Available In this study, a bi-objective model for integrated planning of production-distribution in a multi-level supply chain network with multiple product types and multi time periods is presented. The supply chain network including manufacturers, distribution centers, retailers and final customers is proposed. The proposed model minimizes the total supply chain costs and transforming time of products for customers in the chain. The proposed model is in the class of linear integer programming problems. The complexity of the problem is large and in the literatur, this problem has been shown to be NP-hard. Therefore, for solving this problem, two multi objective meta-heuristic approaches based on Pareto method including non-dominated Sorting Genetic Algorithm-II (NSGA-II and non-dominated Ranking Genetic Algorithm (NRGA have been suggested. Since the output of meta- heuristic algorithms are highly dependent on the input parameters of the algorithm, Taguchi method (Taguchi is used to tune the parameters. Finally, in order to evaluate the performance of the proposed solution methods, different test problems with different dimensions have been produced and the performances of the proposed algorithms on the test problems have been analyzed.
Fast Combinatorial Algorithm for the Solution of Linearly Constrained Least Squares Problems
Van Benthem, Mark H.; Keenan, Michael R.
2008-11-11
A fast combinatorial algorithm can significantly reduce the computational burden when solving general equality and inequality constrained least squares problems with large numbers of observation vectors. The combinatorial algorithm provides a mathematically rigorous solution and operates at great speed by reorganizing the calculations to take advantage of the combinatorial nature of the problems to be solved. The combinatorial algorithm exploits the structure that exists in large-scale problems in order to minimize the number of arithmetic operations required to obtain a solution.
Sopov, E.; Semenkina, O.
2015-01-01
Genetic and distribution building algorithms with binary representation are analyzed. A property of convergence to the optimal solution is discussed. A novel convergence prediction method is proposed and investigated. The method is based on analysis of gene value probabilities distribution dynamics, thus it can predict gene values of the optimal solution to which the algorithm converges. The results of investigations for the optimal prediction algorithm performance are presented.
Kalligiannaki, Evangelia; Plechac, Petr
2012-01-01
We propose a hierarchy of multi-level kinetic Monte Carlo methods for sampling high-dimensional, stochastic lattice particle dynamics with complex interactions. The method is based on the efficient coupling of different spatial resolution levels, taking advantage of the low sampling cost in a coarse space and by developing local reconstruction strategies from coarse-grained dynamics. Microscopic reconstruction corrects possibly significant errors introduced through coarse-graining, leading to the controlled-error approximation of the sampled stochastic process. In this manner, the proposed multi-level algorithm overcomes known shortcomings of coarse-graining of particle systems with complex interactions such as combined long and short-range particle interactions and/or complex lattice geometries. Specifically, we provide error analysis for the approximation of long-time stationary dynamics in terms of relative entropy and prove that information loss in the multi-level methods is growing linearly in time, whic...
Multi level Programming in Multi Site Production Systems Analysis
Directory of Open Access Journals (Sweden)
N. Bakhshizadeh
2016-06-01
Full Text Available Considering the significance of the Supply Chain Management Systems and the due planning related to it, cause that researcher has gathered data on various modeling types about Multi Site Production planning Systems that are actually Supply Chains located in different places geographically. It is worth noting that the presented models are of very short history and they are just under the focus of study after 80's. In the present article, the writer has surveyed the Multi Level Programming Model and after studying the nature and application of such mathematical planning and its due relevance to the subject under the study, the Multi Site Production Systems were selected. It is completely obvious that the active elements in a Supply Chain may not be in total agreement and cooperation with each other and also they may not be in complete opposition with each other, therefore the modeling of the above mentioned systems does not seem to be proper through a usual one-zero or linear planning. The significant points in Multi Level Programming Model are: First, it is hierarchical and therefore it is more efficient in supply chains in which some active elements are more influential and powerful than the others. Second, in this system the decision makers in the upper levels determine their goals and decisions and ask the lower levels of the organization to optimize the goals separately. The lower-level decision makers would present their decisions to the upper-levels and the decisions would be reformed or modified by them, considering the general interests of the organization. The process continues to an optimal or a more satisfactory solution.Thus, the researcher has presented his analytical model (which is itself a consideration of just two steps of this chain: production and supply based on a two-level planning model and has eventually tested his model in a car company
Genetic algorithm in DNA computing:A solution to the maximal clique problem
Institute of Scientific and Technical Information of China (English)
LI Yuan; FANG Chen; OUYANG Qi
2004-01-01
Genetic algorithm is one of the possible ways to break the limit of brute-force method in DNA computing. Using the idea of Darwinian evolution, we introduce a genetic DNA computing algorithm to solve the maximal clique problem. All the operations in the algorithm are accessible with today's molecular biotechnology. Our computer simulations show that with this new computing algorithm, it is possible to get a solution from a very small initial data pool, avoiding enumerating all candidate solutions. For randomly generated problems, genetic algorithm can give correct solution within a few cycles at high probability. Although the current speed of a DNA computer is slow compared with silicon computers, our simulation indicates that the number of cycles needed in this genetic algorithm is approximately a linear function of the number of vertices in the network. This may make DNA computers more powerfully attacking some hard computational problems.
A Numerical Algorithm for the Solution of a Phase-Field Model of Polycrystalline Materials
Energy Technology Data Exchange (ETDEWEB)
Dorr, M R; Fattebert, J; Wickett, M E; Belak, J F; Turchi, P A
2008-12-04
We describe an algorithm for the numerical solution of a phase-field model (PFM) of microstructure evolution in polycrystalline materials. The PFM system of equations includes a local order parameter, a quaternion representation of local orientation and a species composition parameter. The algorithm is based on the implicit integration of a semidiscretization of the PFM system using a backward difference formula (BDF) temporal discretization combined with a Newton-Krylov algorithm to solve the nonlinear system at each time step. The BDF algorithm is combined with a coordinate projection method to maintain quaternion unit length, which is related to an important solution invariant. A key element of the Newton-Krylov algorithm is the selection of a preconditioner to accelerate the convergence of the Generalized Minimum Residual algorithm used to solve the Jacobian linear system in each Newton step. Results are presented for the application of the algorithm to 2D and 3D examples.
Towards Multi-level Optimization: Space-Mapping and Manifold-Mapping
Energy Technology Data Exchange (ETDEWEB)
Echeverria, D; Tong, C
2006-07-24
In this report we study space-mapping and manifold-mapping, two multi-level optimization techniques that aim at accelerating expensive optimization procedures with the aid of simple auxiliary models. Manifold-mapping improves in accuracy the solution given by space-mapping. In this report, the two mentioned techniques are basically described and then applied in the solving of two minimization problems. Several coarse models are tried, both from a two and a three level perspective. The results with these simple tests confirm the speed-up expected for the multi-level approach.
Optimized quantum random-walk search algorithm for multi-solution search
Institute of Scientific and Technical Information of China (English)
张宇超; 鲍皖苏; 汪翔; 付向群
2015-01-01
This study investigates the multi-solution search of the optimized quantum random-walk search algorithm on the hypercube. Through generalizing the abstract search algorithm which is a general tool for analyzing the search on the graph to the multi-solution case, it can be applied to analyze the multi-solution case of quantum random-walk search on the graph directly. Thus, the computational complexity of the optimized quantum random-walk search algorithm for the multi-solution search is obtained. Through numerical simulations and analysis, we obtain a critical value of the proportion of solutions q. For a given q, we derive the relationship between the success rate of the algorithm and the number of iterations when q is no longer than the critical value.
Application layer multicast routing solution based on genetic algorithms
Institute of Scientific and Technical Information of China (English)
Peng CHENG; Qiufeng WU; Qionghai DAI
2009-01-01
Application layer multicast routing is a multi-objective optimization problem.Three routing con-straints,tree's cost,tree's balance and network layer load distribution are analyzed in this paper.The three fitness functions are used to evaluate a multicast tree on the three indexes respectively and one general fitness function is generated.A novel approach based on genetic algorithms is proposed.Numerical simulations show that,compared with geometrical routing rules,the proposed algorithm improve all three indexes,especially on cost and network layer load distribution indexes.
AN EVOLUTIONARY ALGORITHM FOR THE SOLUTION OF WIND THERMAL DISPATCH
Directory of Open Access Journals (Sweden)
K. DHAYALINI
2013-06-01
Full Text Available In this paper, optimal wind and thermal generation dispatch is performed by Evolutionary Algorithm approach. To determine the optimal dispatch scheme that can integrate wind power efficiently and reliably into the conventional system, it is necessary to develop a better wind thermal coordination dispatch. In this paper Evolutionary Algorithm approach is used to coordinate the wind and thermal coordination dispatch. Also to minimize the total production cost in the economic dispatch scheme considering the wind power generation and valve point effect of the thermal units. For numerical simulation ten unit systems incorporating one wind power generation is utilized. Economic dispatch scheme with and without wind power production are simulated.
Adaptive Ant Colony Algorithm for the VRP Solution of Logistics Distribution
Directory of Open Access Journals (Sweden)
Yu-Ping Wang
2013-06-01
Full Text Available In order to conquer the premature convergence problem and lower the cost of computing of the basic Ant Colony Algorithm (ACA, we present an adaptive ant colony algorithm, named AACA, coupled with a Pareto Local Search (PLS algorithm and apply to the Vehicle Routing Problem (VRP and Capacitated VRP (CVRP. By using the information entropy, the algorithm adjusts the pheromone updating strategy adaptively. Experiments on various aspects of the algorithm and computational results for some benchmark problems are reported. We compare our approach with some classic, powerful meta-heuristics and show that the proposed approach can obtain the better quality of the solutions.
Segmentation of hand radiographs by using multi-level connected active appearance models
Kauffman, Joost A.; Slump, Cornelis H.; Bernelot Moens, Hein J.
2005-04-01
Robust and accurate segmentation methods are important for the computerized evaluation of medical images. For treatment of rheumatoid arthritis, joint damage assessment in radiographs of hands is frequently used for monitoring disease progression. Current clinical scoring methods are based on visual measurements that are time-consuming and subject to intra and inter-reader variance. A solution may be found in the development of partially automated assessment procedures. This requires reliable segmentation algorithms. Our work demonstrates a segmentation method based on multiple connected active appearance models (AAM) with multiple search steps using different quality levels. The quality level can be regulated by setting the image resolution and the number of landmarks in the AAMs. We performed experiments using two models of different quality levels for shape and texture information. Both models included AAMs for the carpal region, the metacarpals, and all phalanges. By starting an iterative search with the faster, low-quality model, we were able to determine the initial parameters of the second, high-quality model. After the second search, the results showed successful segmentation for 22 of 30 test images. For these images, 70% of the landmarks were found within 1.3 mm difference from manual placement by an expert. The multi-level search approach resulted in a reduction of 50% in calculation time compared to a search using a single model. Results are expected to improve when the model is refined by increasing the number of training examples and the resolution of the models.
Solution of optimal power flow using evolutionary-based algorithms
African Journals Online (AJOL)
This paper applies two reliable and efficient evolutionary-based methods named Shuffled Frog Leaping Algorithm ... Grey Wolf Optimizer (GWO) to solve Optimal Power Flow (OPF) problem. OPF is ..... The wolves search for the prey based on the alpha, beta, and delta positions. ..... Energy Conversion and Management, Vol.
Institute of Scientific and Technical Information of China (English)
WANG Shunjin; ZHANG Hua
2006-01-01
The problem of preserving fidelity in numerical computation of nonlinear ordinary differential equations is studied in terms of preserving local differential structure and approximating global integration structure of the dynamical system.The ordinary differential equations are lifted to the corresponding partial differential equations in the framework of algebraic dynamics,and a new algorithm-algebraic dynamics algorithm is proposed based on the exact analytical solutions of the ordinary differential equations by the algebraic dynamics method.In the new algorithm,the time evolution of the ordinary differential system is described locally by the time translation operator and globally by the time evolution operator.The exact analytical piece-like solution of the ordinary differential equations is expressd in terms of Taylor series with a local convergent radius,and its finite order truncation leads to the new numerical algorithm with a controllable precision better than Runge Kutta Algorithm and Symplectic Geometric Algorithm.
Directory of Open Access Journals (Sweden)
Khalid. W. Magld
2012-07-01
Full Text Available The Traveling salesman problem (TSP is to find a tour of a given number of cities (visiting each city exactly once where the length of this tour is minimized. Testing every possibility for an N city tour would be N! Math additions. Genetic algorithms (GA and Memetic algorithms (MA are a relatively new optimization technique which can be applied to various problems, including those that are NPhard. The technique does not ensure an optimal solution, however it usually gives good approximations in a reasonable amount of time. They, therefore, would be good algorithms to try on the traveling salesman problem, one of the most famous NP-hard problems. In this paper I have proposed a algorithm to solve TSP using Genetic algorithms (GA and Memetic algorithms (MA with the crossover operator Edge Assembly Crossover (EAX and also analyzed the result on different parameter like group size and mutation percentage and compared the result with other solutions.
Institute of Scientific and Technical Information of China (English)
刘雅蓉; 汪西莉
2012-01-01
In this paper, we propose an adaptive spectral clustering algorithm based on the Nystrom method with multilevel structures in LUV color space. First, we introduce the LUV color space, which can effectively avoid the influence of barely noticeable differences on the segmentation results, achieving better result in texture and edge regions. Second, we combine the spectral clustering algorithm based on multi-level structure and the Nystrom method. Our approach can reduce the operation time and solve the problem of memory overflow. Finally, in X-means, through the analysis of the eigengap to adaptive select the value of K, this approach can automatically determine the number of clusters. The proposed method is applied to image segmentation, respectively, in LUV color space and RGB color space. The experimental results show that in LUV color space we can obtain even better results. The data computation and operation time as well as the segmentation result of the proposed algorithm are superior, compared to the spectral clustering algorithm based on the Nystrom method (SC-N).%提出一种在LUV空间中基于多层次化结构Nystr(o)m方法的自适应谱聚类算法.首先引入LUV色彩空间,避免了RGB色彩空间中色彩辨别阈对分割的影响,在纹理、边缘区域取得了更好的分割效果；其次将谱聚类算法中基于多层次化结构的方法和基于Nystr(o)m采样的方法结合起来,有效减少了运算时间、解决了数据量较大时计算过程中内存溢出的问题；最后在K均值聚类中通过对特征间隙( eigengap)的分析,自适应地选择K值的大小,解决了自动确定聚类数目的问题.将提出的方法在LUV色彩空间中和RGB色彩空间中分别进行图像分割实验,结果表明在LUV色彩空间中取得效果更加理想.同时也将提出的算法与基于Nystr(o)m方法的谱聚类算法(spectral clustering-Nystr(o)m,SC-N)进行比较.实验结果表明,该算法在数据运算量、运行时
Goloviznin, V. M.; Kanaev, A. A.
2012-03-01
The CABARET computational algorithm is generalized to one-dimensional scalar quasilinear hyperbolic partial differential equations with allowance for inequality constraints on the solution. This generalization can be used to analyze seepage of liquid radioactive wastes through the unsaturated zone.
Solution of transient optimization problems by using an algorithm based on nonlinear programming
Teren, F.
1977-01-01
A new algorithm is presented for solution of dynamic optimization problems which are nonlinear in the state variables and linear in the control variables. It is shown that the optimal control is bang-bang. A nominal bang-bang solution is found which satisfies the system equations and constraints, and influence functions are generated which check the optimality of the solution. Nonlinear optimization (gradient search) techniques are used to find the optimal solution. The algorithm is used to find a minimum time acceleration for a turbofan engine.
Institute of Scientific and Technical Information of China (English)
Liu-chuan Zeng
2004-01-01
The purpose of this paper is to investigate the iterative algorithm for finding approximate solutions of a class of mixed variational-like inequalities in a real Hilbert space,where the iterative algorithm is presented by virtue of the auxiliary principle technique.On one hand,the existence of approximate solutions of this class of mixed variational-like inequalities is proven.On the other hand,it is shown that the approximate solutions converge strongly to the exact solution of this class of mixed variational-like inequalities.
Solution of transient optimization problems by using an algorithm based on nonlinear programming
Teren, F.
1977-01-01
A new algorithm is presented for solution of dynamic optimization problems which are nonlinear in the state variables and linear in the control variables. It is shown that the optimal control is bang-bang. A nominal bang-bang solution is found which satisfies the system equations and constraints, and influence functions are generated which check the optimality of the solution. Nonlinear optimization (gradient search) techniques are used to find the optimal solution. The algorithm is used to find a minimum time acceleration for a turbofan engine.
A genetic algorithm for the pareto optimal solution set of multi-objective shortest path problem
Institute of Scientific and Technical Information of China (English)
HU Shi-cheng; XU Xiao-fei; ZHAN De-chen
2005-01-01
Unlike the shortest path problem that has only one optimal solution and can be solved in polynomial time, the multi-objective shortest path problem (MSPP) has a set of pareto optimal solutions and cannot be solved in polynomial time. The present algorithms focused mainly on how to obtain a precisely pareto optimal solution for MSPP resulting in a long time to obtain multiple pareto optimal solutions with them. In order to obtain a set of satisfied solutions for MSPP in reasonable time to meet the demand of a decision maker, a genetic algorithm MSPP-GA is presented to solve the MSPP with typically competing objectives, cost and time, in this paper. The encoding of the solution and the operators such as crossover, mutation and selection are developed.The algorithm introduced pareto domination tournament and sharing based selection operator, which can not only directly search the pareto optimal frontier but also maintain the diversity of populations in the process of evolutionary computation. Experimental results show that MSPP-GA can obtain most efficient solutions distributed all along the pareto frontier in less time than an exact algorithm. The algorithm proposed in this paper provides a new and effective method of how to obtain the set of pareto optimal solutions for other multiple objective optimization problems in a short time.
Directory of Open Access Journals (Sweden)
Alkın Yurtkuran
2016-01-01
Full Text Available The artificial bee colony (ABC algorithm is a popular swarm based technique, which is inspired from the intelligent foraging behavior of honeybee swarms. This paper proposes a new variant of ABC algorithm, namely, enhanced ABC with solution acceptance rule and probabilistic multisearch (ABC-SA to address global optimization problems. A new solution acceptance rule is proposed where, instead of greedy selection between old solution and new candidate solution, worse candidate solutions have a probability to be accepted. Additionally, the acceptance probability of worse candidates is nonlinearly decreased throughout the search process adaptively. Moreover, in order to improve the performance of the ABC and balance the intensification and diversification, a probabilistic multisearch strategy is presented. Three different search equations with distinctive characters are employed using predetermined search probabilities. By implementing a new solution acceptance rule and a probabilistic multisearch approach, the intensification and diversification performance of the ABC algorithm is improved. The proposed algorithm has been tested on well-known benchmark functions of varying dimensions by comparing against novel ABC variants, as well as several recent state-of-the-art algorithms. Computational results show that the proposed ABC-SA outperforms other ABC variants and is superior to state-of-the-art algorithms proposed in the literature.
Institute of Scientific and Technical Information of China (English)
HOU XueLiang; LU Mei
2008-01-01
In order to seek the co-adaptability solution to conflict events in construction en-gineering projects,a new method referred to as segmented hierarchical algorithm is proposed in this paper by means of comparing co-adaptability evolution process of conflict events to the stackelberg model.By this new algorithm,local solutions to the first-order transformation of co-adaptability for conflict events can be ob-tained,based upon which,a global solution to the second-order transformation of co-adaptability for conflict events can also be decided by judging satisfaction de-gree of local solutions.The research results show that this algorithm can be used not only for obtaining co-adaptability solution to conflict events efficiently,but also for other general decision-making problems with multi-layers and multi-subsidi-aries in project management field.
Institute of Scientific and Technical Information of China (English)
2008-01-01
In order to seek the co-adaptability solution to conflict events in construction engineering projects, a new method referred to as segmented hierarchical algorithm is proposed in this paper by means of comparing co-adaptability evolution process of conflict events to the stackelberg model. By this new algorithm, local solutions to the first-order transformation of co-adaptability for conflict events can be obtained, based upon which, a global solution to the second-order transformation of co-adaptability for conflict events can also be decided by judging satisfaction degree of local solutions. The research results show that this algorithm can be used not only for obtaining co-adaptability solution to conflict events efficiently, but also for other general decision-making problems with multi-layers and multi-subsidi-aries in project management field.
Refined multi-level methodology in parallel computing environment for BWR RIA analysis
Solis-Rodarte, Jorge
2000-12-01
Best-estimate methodologies in boiling water reactor can reduce the traditional conservative thermal margins imposed on the designs and during the operation of this type of nuclear reactors. Traditional operating thermal margins are obtained based on simplified modeling techniques that are supplemented with the required dose of conservatism. For instance, much more realistic transient pin peaking distributions can be predicted by applying a dehomogenization algorithm, based on a flux reconstruction scheme which uses nodal results during both steady state and transient calculation at each time step. A subchannel analysis module for obtaining thermal margins supplements the calculation approach used. A multi-level methodology to extend the TRAC-BF1/NEM coupled code capability to obtain the transient fuel rod response has been implemented. To fulfill the development requirements some improved neutronic models were implemented into the NEM solution algorithm, namely the pin power reconstruction capability, and the simulation of a dynamic scram. The obtained results were coupled to a subchannel analysis module: COBRA-TF T-H subchannel analysis code. The objective of the pin power reconstruction capability of NEM is to locate the most limiting node (axial region of assembly/channel) within the core. The power information obtained from the NEM 3D neutronic calculation is used by the hot channel analysis module (COBRA-TF). COBRA-TF needs also the T-H conditions at the boundary nodes. This information is provided by TRACBF1 T-H system analysis code. The Subchannel analysis module uses this information to re-calculate the fluid, thermal and hydraulics conditions in the most limiting node (axial region of assembly/channel) within the core.
Protopopescu, V; Barhen, J
2003-01-01
A constant-time solution of the continuous global optimization problem (GOP) is obtained by using an ensemble algorithm. We show that under certain assumptions, the solution can be guaranteed by mapping the GOP onto a discrete unsorted search problem, whereupon Brueschweiler's ensemble search algorithm is applied. For adequate sensitivities of the measurement technique, the query complexity of the ensemble search algorithm depends linearly on the size of the function's domain. Advantages and limitations of an eventual NMR implementation are discussed. (letter to the editor)
Multi-Level Steganography: Improving Hidden Communication in Networks
Fraczek, Wojciech; Szczypiorski, Krzysztof
2011-01-01
The paper presents Multi-Level Steganography (MLS), which defines a new concept for hidden communication. In MLS, at least two steganographic methods are utilised simultaneously, in such a way that one method (called the upper-level) serves as a carrier for the second one (called the lower-level). Such a relationship between two (or more) information hiding solutions has several potential benefits. The most important is that the lower-level method steganographic bandwidth can be utilised to make the steganogram unreadable even after the detection of the upper-level method: e.g., it can carry a cryptographic key that deciphers the steganogram carried by the upper-level one. It can also be used to provide the steganogram with integrity. Another important benefit is that the lower-layer method may be used as a signalling channel in which to exchange information that affects the way that the upper-level method functions, thus possibly making the steganographic communication harder to detect. MLS is presented in t...
Directory of Open Access Journals (Sweden)
Özgür Başkan
2014-09-01
Full Text Available Differential Evolution algorithm has effectively been used to solve engineering optimization problems recently. The Differential Evolution algorithm, which uses similar principles with Genetic Algorithms, is more robust on obtaining optimal solution than many other heuristic algorithms with its simpler structure. In this study, Differential Evolution algorithm is applied to the transportation network design problems and its effectiveness on the solution is investigated. In this context, Differential Evolution based models are developed using bi-level programming approach for the solution of the transportation network design problem and determination of the on-street parking places in urban road networks. In these models, optimal investment and parking strategies are investigated on the upper level. On the lower level, deterministic traffic assignment problem, which represents drivers' responses, is solved using Frank-Wolfe algorithm and VISUM traffic modeling software. In order to determine the effectiveness of the proposed models, numerical applications are carried out on Sioux-Falls test network. Results showed that the Differential Evolution algorithm may effectively been used for the solution of transportation network design problems.
Directory of Open Access Journals (Sweden)
Ji-Huan He
2012-01-01
Full Text Available This paper applies an ancient Chinese algorithm to differential-difference equations, and a solitary-solution formulation is obtained. The discrete mKdV lattice equation is used as an example to elucidate the solution procedure.
The Geography of International Strategy: a multi-level framework
D. van den Berghe (Douglas)
2001-01-01
textabstractThis article introduces a multi-level framework to structure and analyse FDI patterns. It is argued that three internationalisation strategies currently simultaneously shape the globalisation of Foreign Direct Investment (FDI): classical internationalisation, emerging
The Geography of International Strategy: a multi-level framework
D. van den Berghe (Douglas)
2001-01-01
textabstractThis article introduces a multi-level framework to structure and analyse FDI patterns. It is argued that three internationalisation strategies currently simultaneously shape the globalisation of Foreign Direct Investment (FDI): classical internationalisation, emerging internationalisatio
PENERAPAN HIRARKI DATA SQL DALAM MULTI LEVEL MARKETING
National Research Council Canada - National Science Library
Sendi Novianto
2012-01-01
.... Multi Level Marketing (MLM) merupakan suatu strategi pemasaran di mana tenaga penjualan mendapatkan kompensasi tidak hanya untuk penjualan tapi, tetapi juga untuk penjualan orang lain yang mereka rekrut, menciptakan suatu...
Efficiency of algorithm for solution of vector radiative transfer equation in turbid medium slab
Budak, V. P.; Efremenko, D. S.; Shagalov, O. V.
2012-06-01
The numerical solution of the vectorial radiative transfer equation (VRTE) is possible only by its discretization, which requires elimination of the solution anisotropic part including all the singularities. Discretized VRTE for the turbid medium slab has the unique analytical solution in the matrix form. Modern packages of matrix (linear) algebra allow only one possible algorithm of VRTE solution by computer. Various realizations of such an algorithm differ by the method of the elimination of the solution anisotropic part. Methods of the solution anisotropic part elimination are analysed in the paper. The codes created by the authors of these methods are analysed in simple situations in order to define its influence on the code efficiency. It is shown that the most effective method is based on the small angle modification of the spherical harmonics method (MSH). The code based on MSH is investigated in details by the influence of different properties of hard and software.
Strategi Perekrutan Prospek di Multi Level Marketing TIENS Kota Medan
Vellayati, Naila
2013-01-01
This research entitled prospects recruitment strategy in multi level marketing of TIENS, Medan. This research’s aim is to recognize the recruiting strategy of the prospects and boundaries in recruiting the prospects in multi level marketing of TIENS, Medan. The research methodology that being used is descriptive method in which only describes a situation or event systematically and neither seeks nor explains the relationships, also neither hypotheses test nor make predictions. In a more st...
Integration of Finite Element Method with Runge – Kuta Solution Algorithm
Directory of Open Access Journals (Sweden)
Olawale Simon
2017-05-01
Full Text Available Runge – Kuta (RK method is reasonably simple and robust for numerical solution of differential equations but it requires an intelligent adaptive step-size routine; to achieve this, there is need to develop a good logical computer code. This study develops a finite element code in Java using Runge-Kuta method as a solution algorithm to predict dynamic time response of structural beam under impulse load. The solution obtained using direct integration and the present work is comparable.
Comparative study of fusion algorithms and implementation of new efficient solution
Besrour, Amine; Snoussi, Hichem; Siala, Mohamed; Abdelkefi, Fatma
2014-05-01
High Dynamic Range (HDR) imaging has been the subject of significant researches over the past years, the goal of acquiring the best cinema-quality HDR images of fast-moving scenes using an efficient merging algorithm has not yet been achieved. In fact, through the years, many efficient algorithms have been implemented and developed. However, they are not yet efficient since they don't treat all the situations and they have not enough speed to ensure fast HDR image reconstitution. In this paper, we will present a full comparative analyze and study of the available fusion algorithms. Also, we will implement our personal algorithm which can be more optimized and faster than the existed ones. We will also present our investigated algorithm that has the advantage to be more optimized than the existing ones. This merging algorithm is related to our hardware solution allowing us to obtain four pictures with different exposures.
AN EFFECTIVE CONTINUOUS ALGORITHM FOR APPROXIMATE SOLUTIONS OF LARGE SCALE MAX-CUT PROBLEMS
Institute of Scientific and Technical Information of China (English)
Cheng-xian Xu; Xiao-liang He; Feng-min Xu
2006-01-01
An effective continuous algorithm is proposed to find approximate solutions of NP-hard max-cut problems. The algorithm relaxes the max-cut problem into a continuous nonlinear programming problem by replacing n discrete constraints in the original problem with one single continuous constraint. A feasible direction method is designed to solve the resulting nonlinear programming problem. The method employs only the gradient evaluations of the objective function, and no any matrix calculations and no line searches are required.This greatly reduces the calculation cost of the method, and is suitable for the solution of large size max-cut problems. The convergence properties of the proposed method to KKT points of the nonlinear programming are analyzed. If the solution obtained by the proposed method is a global solution of the nonlinear programming problem, the solution will provide an upper bound on the max-cut value. Then an approximate solution to the max-cut problem is generated from the solution of the nonlinear programming and provides a lower bound on the max-cut value. Numerical experiments and comparisons on some max-cut test problems (small and large size) show that the proposed algorithm is efficient to get the exact solutions for all small test problems and well satisfied solutions for most of the large size test problems with less calculation costs.
An adaptive solution domain algorithm for solving multiphase flow equations
Katyal, A. K.; Parker, J. C.
1992-01-01
An adaptive solution domain (ASD) finite-element model for simulating hydrocarbon spills has been developed that is computationally more efficient than conventional numerical methods. Coupled flow of water and oil with an air phase at constant pressure is considered. In the ASD formulation, the solution domain for water- and oil-flow equations is restricted by eliminating elements from the global matrix assembly which are not experiencing significant changes in fluid saturations or pressures. When any nodes of an element exhibit changes in fluid pressures more than a stipulated tolerance τ, or changes in fluid saturations greater than tolerance τ 2 during the current time step, it is labeled active and included in the computations for the next iteration. This formulation achieves computational efficiency by solving the flow equations for only the part of the domain where changes in fluid pressure or the saturations take place above stipulated tolerances. Examples involving infiltration and redistribution of oil in 1- and 2-D spatial domains are described to illustrate the application of the ASD method and the savings in the processor time achieved by this formulation. Savings in the computational effort up to 84% during infiltration and 63% during redistribution were achieved for the 2-D example problem.
COMPARISON OF TDOA LOCATION ALGORITHMS WITH DIRECT SOLUTION METHOD
Institute of Scientific and Technical Information of China (English)
Li Chun; Liu Congfeng; Liao Guisheng
2011-01-01
For Time Difference Of Arrival (TDOA) location based on multi-ground stations scene,two direct solution methods are proposed to solve the target position in TDOA location.Therein,the solving methods are realized in the rectangular and polar coordinates.On the condition of rectangular coordinates,first of all,it solves the radial range between the target and reference station,then calculates the location of the target.In the case of polar coordinates,the azimuth between the target and reference station is solved first,then the radial range between the target and reference station is figured out,finally the location of the target is obtained.Simultaneously,the simulation and comparison analysis are given in detail,and show that the polar solving method has the better fuzzy performance than that of rectangular coordinate.
A 3D radiative transfer framework: XI. multi-level NLTE
Hauschildt, Peter H
2014-01-01
Multi-level non-local thermodynamic equilibrium (NLTE) radiation transfer calculations have become standard throughout the stellar atmospheres community and are applied to all types of stars as well as dynamical systems such as novae and supernovae. Even today spherically symmetric 1D calculations with full physics are computationally intensive. We show that full NLTE calculations can be done with fully 3 dimensional (3D) radiative transfer. With modern computational techniques and current massive parallel computational resources, full detailed solution of the multi-level NLTE problem coupled to the solution of the radiative transfer scattering problem can be solved without sacrificing the micro physics description. We extend the use of a rate operator developed to solve the coupled NLTE problem in spherically symmetric 1D systems. In order to spread memory among processors we have implemented the NLTE/3D module with a hierarchical domain decomposition method that distributes the NLTE levels, radiative rates,...
Preliminary Analysis on the Relative Solution Space Sizes for MTSP with Genetic Algorithm
Hao, Junling
It is well known that the chromosome design is pivotal to solve the multiple traveling salesman problems with genetic algorithm. A well-designed chromosome coding can eliminate or reduce the redundant solutions. One chromosome and two chromosome design methods and a recently proposed two-part chromosome design are firstly introduced in this paper. Then the preliminary quantitative comparison analysis of the solution spaces of three different chromosome design methods is presented when the number of cities is linear with the travelers. The concept of relative solution space is proposed in order to compare the relative size of the solution spaces. The solution space of two-part chromosome design is much smaller than those of the traditional chromosome design. The result given in this paper provides a good guideline for the possible algorithmic design and engineering applications.
A numerical solution algorithm and its application to studies of pulsed light fields propagation
Banakh, V. A.; Gerasimova, L. O.; Smalikho, I. N.; Falits, A. V.
2016-08-01
A new method for studies of pulsed laser beams propagation in a turbulent atmosphere was proposed. The algorithm of numerical simulation is based on the solution of wave parabolic equation for complex spectral amplitude of wave field using method of splitting into physical factors. Examples of the use of the algorithm in the case the propagation pulsed Laguerre-Gaussian beams of femtosecond duration in the turbulence atmosphere has been shown.
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.
Institute of Scientific and Technical Information of China (English)
YAN Zhen-Ya
2004-01-01
A Weierstrass elliptic function expansion method and its algorithm are developed in this paper. The method changes the problem solving nonlinear evolution equations into another one solving the correspondingsystem of nonlinear algebraic equations. With the aid of symbolic computation (e.g. Maple), the method is applied to the combined KdV-mKdV equation and (2+1)-dimensional coupled Davey-Stewartson equation. As a consequence, many new types of doubly periodic solutions are obtained in terms of the Weierstrass elliptic function. Jacobi elliptic function solutions and solitary wave solutions are also given as simple limits of doubly periodic solutions.
Institute of Scientific and Technical Information of China (English)
YANZhen-Ya
2004-01-01
A Weierstrass elliptic function expansion method and its algorithm are developed in this paper. The method changes the problem solving nonlinear evolution equations into another one solving the corresponding system of nonlinear algebraic equations. With the aid of symbolic computation (e.g. Maple), the method is applied to the combined KdV-mKdV equation and (2+1)-dimensional coupled Davey-Stewartson equation. As a consequence, many new types of doubly periodic solutions are obtained in terms of the Weierstrass elliptic function. Jacobi elliptic function solutions and solitary wave solutions are also given as simple limits of doubly periodic solutions.
Institute of Scientific and Technical Information of China (English)
ZENG Luchuan
2004-01-01
The purpose of this paper is to introduce and study a new class of generalized strongly mixed implicit quasi-variational inequalities in Hilbert spaces, which includes the known class of generalized mixed implicit quasi-variational inequalities as a special case.By applying the auxiliary variational principle technique, the existence of solutions for this class of quasi-variational inequalities is proved. Moreover, a new iterative algorithm for computing approximate solutions is constructed and the convergence criteria for this iterative algorithm are also established.
On multi-level thinking and scientific understanding
McIntyre, Michael Edgeworth
2017-10-01
Professor Duzheng YE's name has been familiar to me ever since my postdoctoral years at MIT with Professors Jule CHARNEY and Norman PHILLIPS, back in the late 1960s. I had the enormous pleasure of meeting Professor YE personally in 1992 in Beijing. His concern to promote the very best science and to use it well, and his thinking on multi-level orderly human activities, reminds me not only of the communication skills we need as scientists but also of the multi-level nature of science itself. Here I want to say something (a) about what science is; (b) about why multi-level thinking—and taking more than one viewpoint—is so important for scientific as well as for other forms of understanding; and (c) about what is meant, at a deep level, by "scientific understanding" and trying to communicate it, not only with lay persons but also across professional disciplines. I hope that Professor YE would approve.
Gaussian translation operator for Multi-Level Fast Multipole Method
DEFF Research Database (Denmark)
Borries, Oscar Peter; Hansen, Per Christian; Sorensen, Stig B.
2014-01-01
Results using a new translation operator for the Multi-Level Fast Multipole Method are presented. Based on Gaussian beams, the translation operator allows a significant portion of the plane-wave directions to be neglected, resulting in a much faster translation step.......Results using a new translation operator for the Multi-Level Fast Multipole Method are presented. Based on Gaussian beams, the translation operator allows a significant portion of the plane-wave directions to be neglected, resulting in a much faster translation step....
Lindegren, Lennart; Hobbs, David; O'Mullane, William; Bastian, Ulrich; Hernández, José
2011-01-01
The Gaia satellite will observe about one billion stars and other point-like sources. The astrometric core solution will determine the astrometric parameters (position, parallax, and proper motion) for a subset of these sources, using a global solution approach which must also include a large number of parameters for the satellite attitude and optical instrument. The accurate and efficient implementation of this solution is an extremely demanding task, but crucial for the outcome of the mission. We provide a comprehensive overview of the mathematical and physical models applicable to this solution, as well as its numerical and algorithmic framework. The astrometric core solution is a simultaneous least-squares estimation of about half a billion parameters, including the astrometric parameters for some 100 million well-behaved so-called primary sources. The global nature of the solution requires an iterative approach, which can be broken down into a small number of distinct processing blocks (source, attitude,...
Comparison of Nonequilibrium Solution Algorithms Applied to Chemically Stiff Hypersonic Flows
Palmer, Grant; Venkatapathy, Ethiraj
1995-01-01
Three solution algorithms, explicit under-relaxation, point implicit, and lower-upper symmetric Gauss-Seidel, are used to compute nonequilibrium flow around the Apollo 4 return capsule at the 62-km altitude point in its descent trajectory. By varying the Mach number, the efficiency and robustness of the solution algorithms were tested for different levels of chemical stiffness.The performance of the solution algorithms degraded as the Mach number and stiffness of the flow increased. At Mach 15 and 30, the lower-upper symmetric Gauss-Seidel method produces an eight order of magnitude drop in the energy residual in one-third to one-half the Cray C-90 computer time as compared to the point implicit and explicit under-relaxation methods. The explicit under-relaxation algorithm experienced convergence difficulties at Mach 30 and above. At Mach 40 the performance of the lower-upper symmetric Gauss-Seidel algorithm deteriorates to the point that it is out performed by the point implicit method. The effects of the viscous terms are investigated. Grid dependency questions are explored.
Institute of Scientific and Technical Information of China (English)
WANG Shundin; ZHANG Hua
2008-01-01
Using functional derivative technique In quantum field theory,the algebraic dy-namics approach for solution of ordinary differential evolution equations was gen-eralized to treat partial differential evolution equations.The partial differential evo-lution equations were lifted to the corresponding functional partial differential equations in functional space by Introducing the time translation operator.The functional partial differential evolution equations were solved by algebraic dynam-ics.The algebraic dynamics solutions are analytical In Taylor series In terms of both initial functions and time.Based on the exact analytical solutions,a new nu-merical algorithm-algebraic dynamics algorithm was proposed for partial differ-ential evolution equations.The difficulty of and the way out for the algorithm were discussed.The application of the approach to and computer numerical experi-ments on the nonlinear Burgers equation and meteorological advection equation indicate that the algebraic dynamics approach and algebraic dynamics algorithm are effective to the solution of nonlinear partial differential evolution equations both analytically and numerically.
Chatfield, David C.; Reeves, Melissa S.; Truhlar, Donald G.; Duneczky, Csilla; Schwenke, David W.
1992-01-01
Complex dense matrices corresponding to the D + H2 and O + HD reactions were solved using a complex generalized minimal residual (GMRes) algorithm described by Saad and Schultz (1986) and Saad (1990). To provide a test case with a different structure, the H + H2 system was also considered. It is shown that the computational effort for solutions with the GMRes algorithm depends on the dimension of the linear system, the total energy of the scattering problem, and the accuracy criterion. In several cases with dimensions in the range 1110-5632, the GMRes algorithm outperformed the LAPACK direct solver, with speedups for the linear equation solution as large as a factor of 23.
Rapid solution of kriging equations, using a banded Gauss elimination algorithm
Energy Technology Data Exchange (ETDEWEB)
Carr, J.R. (University of Nevada, Reno, NV (USA))
1990-12-01
A crucial concern when implementing computer algorithms for geostatistical analyses on microcomputers is speed of execution. Kriging, in particular, typically relies on a Gauss elimination algorithm to solve for weights. Because such an alogrithm is required for each estimate, the solution for weights can result in very slow program execution speed on a microcomputer. One approach to enhancing the efficiency of Gauss elimination is demonstrated herein. The upper triangle plus diagonal of the intersample covariance matrix is used in a modified banded Gauss elimination algorithm. Results show that such an algorithm yields approximately a two-fold reduction in execution time for kriging when the number of nearest neighbours used for estimation is large. 4 refs., 2 figs., 1 tab.
Multi-level Reconfigurable Self-organization in Overlay Services
Pournaras, E.
2013-01-01
Large-scale decentralized systems organized in overlay networks are complex to manage. Such systems integrate organizational complexity in the application-level resulting in low abstraction and modularity in their services. This thesis introduces a multi-level conceptual architecture for overlay
A Logic of Multi-Level Change of Routines
Nooteboom, B.
2005-01-01
This paper tries to account for endogenous change of multi-level routines in terms of nested cycles of discovery, in a hierarchy of scripts.Higher-level scripts constitute the selection environment for lower level ones.On any level, a cycle of discovery proceeds from established dominant designs.Whe
Multi-level Reconfigurable Self-organization in Overlay Services
Pournaras, E.
2013-01-01
Large-scale decentralized systems organized in overlay networks are complex to manage. Such systems integrate organizational complexity in the application-level resulting in low abstraction and modularity in their services. This thesis introduces a multi-level conceptual architecture for overlay ser
Multi-level Reconfigurable Self-organization in Overlay Services
Pournaras, E.
2013-01-01
Large-scale decentralized systems organized in overlay networks are complex to manage. Such systems integrate organizational complexity in the application-level resulting in low abstraction and modularity in their services. This thesis introduces a multi-level conceptual architecture for overlay ser
Multi-Level Strategies in Universities: Coordination, Contestation or Creolisation?
Stensaker, Bjørn; Fumasoli, Tatiana
2017-01-01
In contemporary research-intensive universities, strategies are not only found at the institutional level but also at various sub-levels in the organisation. In principle, such multi-level strategies are assumed to be a means for institutional coordination in the sense that more generic strategic objectives may give room for local adaptation…
Multi-Level Security Cannot Realise NEC Objectives
Schotanus, H.A.; Hartog, T.; Verkoelen, C.A.A.
2012-01-01
Multi-Level Security (MLS) is often viewed as the holy grail of information security, especially in those environments where information of different classifications is being processed. In this paper we argue that MLS cannot facilitate the right balance between need-to-protect and duty-to-share as r
Institute of Scientific and Technical Information of China (English)
曾六川
2003-01-01
A new class of general multivalued mixed implicit quasi-variational inequalities in a real Hilbert space was introduced, which includes the known class of generalized mixed implicit quasi-variational inequalities as a special case, introduced and studied by Ding Xieping. The auxiliary variational principle technique was applied to solve this class of general multivalued mixed implicit quasi-variational inequalities. Firstly, a new auxiliary variational inequality with a proper convex, lower semicontinuous, binary functional was defined and a suitable functional was chosen so that its unique minimum point is equivalent to the solution of such an auxiliary variational inequality. Secondly, this auxiliary variational inequality was utilized to construct a new iterative algorithm for computing approximate solutions to general multivalued mixed implicit quasi-variational inequalities. Here, the equivalence guarantees that the algorithm can generate a sequence of approximate solutions.Finally, the existence of solutions and convergence of approximate solutions for general multivalued mixed implicit quasi-variational inequalities are proved. Moreover, the new convergerce criteria for the algorithm were provided. Therefore, the results give an affirmative anwer to the open question raised by M . A. Noor , and extend and improve the earlier and recent results for various variational inequalities and complementarity problems including the corresponding results for mixed variational inequalities, mixed quasi-variational inequalities and quasi-complementarity problems involving the single-valued and set-valued mappings in the recent literature.
Directory of Open Access Journals (Sweden)
Liying Zhang
2013-11-01
Full Text Available Compared with the conventional control systems, networked control systems (NCSs are more open to the external network. As a result, they are more vulnerable to attacks from disgruntled insiders or malicious cyber-terrorist organizations. Therefore, the security issues of NCSs have been receiving a lot of attention recently. In this brief, we review the existing literature on security issues of NCSs and propose some security solutions for the DC motor networked control system. The typical Data Encryption Standard (DES algorithm is adopted to implement data encryption and decryption. Furthermore, we design a Detection and Reaction Mechanism (DARM on the basis of DES algorithm and the improved grey prediction model. Finally, our proposed security solutions are tested with the established models of deception and DOS attacks. According to the results of numerical experiments, it's clear to see the great feasibility and effectiveness of the proposed solutions above.
Multi-Level Round-Robin Multicast Scheduling with Look-Ahead Mechanism
DEFF Research Database (Denmark)
Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert
2011-01-01
In this paper, we propose a multi-level round-robin multicast scheduling (MLRRMS) algorithm with look-ahead (LA) mechanism for N×N input-queued switches. Fan-out splitting is applied, where a multicast cell can be transferred to all its destinations over any number of cell times. The scheduler...... constructs the Traffic Matrix before each cell transmission based on the fan-out vectors of the cells in the queues. A scheduling pointer independently moves on each column of the Traffic Matrix in a round-robin fashion and returns the decision to the Decision Matrix. The sync procedure is carried out...
Design and implementation of a DSP with multi-level low power strategies for cochlear implants
Institute of Scientific and Technical Information of China (English)
Mai Songping; Zhang Chun; Chao Jun; Wang Zhihua
2009-01-01
This paper presents the design and implementation of a low power digital signal processor (THUCIDSP-1) targeting at application for cochlear implants. Multi-level low power strategies including algorithm optimization, operand isolation, clock gating and memory partitioning are adopted in the processor design to reduce the power consumption. Experimental results show that the complexity of the Continuous Interleaved Sampling (CIS) algorithm is reduced by more than 80% and the power dissipation of the hardware alone is reduced by about 25% with the low power methods. The THUCIDSP-1 prototype, fabricated in 0.18-μm standard CMOS process, consumes only 1.91 mW when executing the CIS algorithm at 3 MHz.
Directory of Open Access Journals (Sweden)
Yudong Zhang
2011-04-01
Full Text Available This paper proposes a global multi-level thresholding method for image segmentation. As a criterion for this, the traditional method uses the Shannon entropy, originated from information theory, considering the gray level image histogram as a probability distribution, while we applied the Tsallis entropy as a general information theory entropy formalism. For the algorithm, we used the artificial bee colony approach since execution of an exhaustive algorithm would be too time-consuming. The experiments demonstrate that: 1 the Tsallis entropy is superior to traditional maximum entropy thresholding, maximum between class variance thresholding, and minimum cross entropy thresholding; 2 the artificial bee colony is more rapid than either genetic algorithm or particle swarm optimization. Therefore, our approach is effective and rapid.
Institute of Scientific and Technical Information of China (English)
2008-01-01
Using functional derivative technique in quantum field theory, the algebraic dy-namics approach for solution of ordinary differential evolution equations was gen-eralized to treat partial differential evolution equations. The partial differential evo-lution equations were lifted to the corresponding functional partial differential equations in functional space by introducing the time translation operator. The functional partial differential evolution equations were solved by algebraic dynam-ics. The algebraic dynamics solutions are analytical in Taylor series in terms of both initial functions and time. Based on the exact analytical solutions, a new nu-merical algorithm—algebraic dynamics algorithm was proposed for partial differ-ential evolution equations. The difficulty of and the way out for the algorithm were discussed. The application of the approach to and computer numerical experi-ments on the nonlinear Burgers equation and meteorological advection equation indicate that the algebraic dynamics approach and algebraic dynamics algorithm are effective to the solution of nonlinear partial differential evolution equations both analytically and numerically.
Alfonso, Lester; Zamora, Jose; Cruz, Pedro
2015-04-01
The stochastic approach to coagulation considers the coalescence process going in a system of a finite number of particles enclosed in a finite volume. Within this approach, the full description of the system can be obtained from the solution of the multivariate master equation, which models the evolution of the probability distribution of the state vector for the number of particles of a given mass. Unfortunately, due to its complexity, only limited results were obtained for certain type of kernels and monodisperse initial conditions. In this work, a novel numerical algorithm for the solution of the multivariate master equation for stochastic coalescence that works for any type of kernels and initial conditions is introduced. The performance of the method was checked by comparing the numerically calculated particle mass spectrum with analytical solutions obtained for the constant and sum kernels, with an excellent correspondence between the analytical and numerical solutions. In order to increase the speedup of the algorithm, software parallelization techniques with OpenMP standard were used, along with an implementation in order to take advantage of new accelerator technologies. Simulations results show an important speedup of the parallelized algorithms. This study was funded by a grant from Consejo Nacional de Ciencia y Tecnologia de Mexico SEP-CONACYT CB-131879. The authors also thanks LUFAC® Computacion SA de CV for CPU time and all the support provided.
Energy Technology Data Exchange (ETDEWEB)
Makeechev, V.A. [Industrial Power Company, Krasnopresnenskaya Naberejnaya 12, 123610 Moscow (Russian Federation); Soukhanov, O.A. [Energy Systems Institute, 1 st Yamskogo Polya Street 15, 125040 Moscow (Russian Federation); Sharov, Y.V. [Moscow Power Engineering Institute, Krasnokazarmennaya Street 14, 111250 Moscow (Russian Federation)
2008-07-15
This paper presents foundations of the optimization method intended for solution of power systems operation problems and based on the principles of functional modeling (FM). This paper also presents several types of hierarchical FM algorithms for economic dispatch in these systems derived from this method. According to the FM method a power system is represented by hierarchical model consisting of systems of equations of lower (subsystem) levels and higher level system of connection equations (SCE), in which only boundary variables of subsystems are present. Solution of optimization problem in accordance with the FM method consists of the following operations: (1) solution of optimization problem for each subsystem (values of boundary variables for subsystems should be determined on the higher level of model); (2) calculation of functional characteristic (FC) of each subsystem, pertaining to state of subsystem on current iteration (these two steps are carried out on the lower level of the model); (3) formation and solution of the higher level system of equations (SCE), which gives values of boundary and supplementary boundary variables on current iteration. The key elements in the general structure of the FM method are FCs of subsystems, which represent them on the higher level of the model as ''black boxes''. Important advantage of hierarchical FM algorithms is that results obtained with them on each iteration are identical to those of corresponding basic one level algorithms. (author)
Routing Flow-Shop with Buffers and Ready Times – Comparison of Selected Solution Algorithms
Directory of Open Access Journals (Sweden)
Józefczyk Jerzy
2014-12-01
Full Text Available This article extends the former results concerning the routing flow-shop problem to minimize the makespan on the case with buffers, non-zero ready times and different speeds of machines. The corresponding combinatorial optimization problem is formulated. The exact as well as four heuristic solution algorithms are presented. The branch and bound approach is applied for the former one. The heuristic algorithms employ known constructive idea proposed for the former version of the problem as well as the Tabu Search metaheuristics. Moreover, the improvement procedure is proposed to enhance the quality of both heuristic algorithms. The conducted simulation experiments allow evaluating all algorithms. Firstly, the heuristic algorithms are compared with the exact one for small instances of the problem in terms of the criterion and execution times. Then, for larger instances, the heuristic algorithms are mutually compared. The case study regarding the maintenance of software products, given in the final part of the paper, illustrates the possibility to apply the results for real-world manufacturing systems.
A multi-level approach to flood frequency regionalisation
Directory of Open Access Journals (Sweden)
C. De Michele
2002-01-01
Full Text Available A multi-level approach to flood frequency regionalisation is given. Based on observed flood data, it combines physical and statistical criteria to cluster homogeneous groups in a geographical area. Seasonality analysis helps identify catchments with a common flood generation mechanism. Scale invariance of annual maximum flood, as parameterised by basin area, is used to check the regional homogeneity of flood peaks. Homogeneity tests are used to assess the statistical robustness of the regions. The approach is based on the appropriate use of the index flood method (Dalrymple, 1960 in regions with complex climate and topography controls. An application to north-western Italy is presented. Keywords: homogeneity, multi-level approach, regionalisation, seasonality, scale invariance, similarity, tests
Multi-stage decoding of multi-level modulation codes
Lin, Shu; Kasami, Tadao; Costello, Daniel J., Jr.
1991-01-01
Various types of multi-stage decoding for multi-level modulation codes are investigated. It is shown that if the component codes of a multi-level modulation code and types of decoding at various stages are chosen properly, high spectral efficiency and large coding gain can be achieved with reduced decoding complexity. Particularly, it is shown that the difference in performance between the suboptimum multi-stage soft-decision maximum likelihood decoding of a modulation code and the single-stage optimum soft-decision decoding of the code is very small, only a fraction of dB loss in signal to noise ratio at a bit error rate (BER) of 10(exp -6).
A Study On Direct Selling Through Multi Level Marketing
Merlin, F. Mary
2012-09-01
Direct selling is a multi-level marketing in which the sales force is compensated not only for the sales they make but also for the sales done through their recruit. This recruited sales force is referred to as the participants who can provide multiple levels of compensation.A person's job would be to recruit others to sell their product, and in return, receive a percentage of their sales. The next person's job then is to recruit people even more so below them, and receive a percentage of their sales. Other terms for Multi-level marketing include network marketing and referral marketing. Commonly, the salespeople are expected to sell products directly to consumers by means of relationship through referrals marketing. Some people use direct selling as a synonym for MLM, although MLM is only one type of direct selling
Quantum state preparation using multi-level-atom optics
Energy Technology Data Exchange (ETDEWEB)
Busch, Th [Physics Department, University College Cork, Cork (Ireland); Deasy, K [Photonics Centre, Tyndall National Institute, Prospect Row, Cork (Ireland); Chormaic, S Nic [Physics Department, University College Cork, Cork (Ireland)
2007-10-15
One of the most important characteristics for controlling processes on the quantum scale is the fidelity or robustness of the techniques being used. In the case of single atoms localized in micro-traps, it was recently shown that the use of time-dependent tunnelling interactions in a multi-trap setup can be viewed as analogous to the area of multi-level optics. The atom's centre-of-mass can then be controlled with a high fidelity, using a STIRAP-type process. Here, we review previous work that led to the development of multi-level atom optics and present two examples of our most recent work on quantum state preparation.
Quantum state preparation using multi-level-atom optics
Busch, Th; Deasy, K.; Chormaic, S. Nic
2007-10-01
One of the most important characteristics for controlling processes on the quantum scale is the fidelity or robustness of the techniques being used. In the case of single atoms localized in micro-traps, it was recently shown that the use of time-dependent tunnelling interactions in a multi-trap setup can be viewed as analogous to the area of multi-level optics. The atom's centre-of-mass can then be controlled with a high fidelity, using a STIRAP-type process. Here, we review previous work that led to the development of multi-level atom optics and present two examples of our most recent work on quantum state preparation.
Zhu, Chun; Li, Run; Que, Li-Zhi; Zhu, Tuo; Chen, Guo-Qing
2014-07-01
The three-dimensional spectra of mixed solutions of allure red, sunset yellow and brilliant blue were obtained. Then the three synthetic food colors were determined by parallel factor analysis (PARAFAC) and alternating trilinear decomposition (ATLD) algorithms, respectively. The component number of model is three by core-consistency diagnostic. The average recoveries of allure red, sunset yellow and brilliant blue obtained by PARAFAC were 98.75% +/- 8.9%, 97.22% +/- 2.9% and 99.00% +/- 2.9% and those by ATLD algorithm were 99.78% +/- 5.9%, 92.52% +/- 5.5% and 97.23% +/- 5.8%, respectively. Results show that both of the algorithms can be used in direct and rapid determination of multi-components of mixtures. From further comparison, the PARAFAC is more stable and advantageous.
Institute of Scientific and Technical Information of China (English)
WANG Yi-bo; YANG Hai-tian; WU Rui-feng
2005-01-01
By modeling direct transient heat conduction problems via finite element method (FEM) and precise integral algorithm, a new approach is presented to solve transient inverse heat conduction problems with multi-variables. Firstly, the spatial space and temporal domain are discretized by FEM and precise integral algorithm respectively. Then, the high accuracy semi-analytical solution of direct problem can be got. Finally, based on the solution, the computing model of inverse problem and expression of sensitivity analysis are established. Single variable and variables combined identifications including thermal parameters, boundary conditions and source-related terms etc. are given to validate the approach proposed in 1-D and 2-D cases. The effects of noise data and initial guess on the results are investigated. The numerical examples show the effectiveness of this approach.
Directory of Open Access Journals (Sweden)
Uamporn Witthayarat
2012-01-01
Full Text Available The aim of this paper is to introduce an iterative algorithm for finding a common solution of the sets (A+M2−1(0 and (B+M1−1(0, where M is a maximal accretive operator in a Banach space and, by using the proposed algorithm, to establish some strong convergence theorems for common solutions of the two sets above in a uniformly convex and 2-uniformly smooth Banach space. The results obtained in this paper extend and improve the corresponding results of Qin et al. 2011 from Hilbert spaces to Banach spaces and Petrot et al. 2011. Moreover, we also apply our results to some applications for solving convex feasibility problems.
Investigation of ALEGRA shock hydrocode algorithms using an exact free surface jet flow solution.
Energy Technology Data Exchange (ETDEWEB)
Hanks, Bradley Wright.; Robinson, Allen C
2014-01-01
Computational testing of the arbitrary Lagrangian-Eulerian shock physics code, ALEGRA, is presented using an exact solution that is very similar to a shaped charge jet flow. The solution is a steady, isentropic, subsonic free surface flow with significant compression and release and is provided as a steady state initial condition. There should be no shocks and no entropy production throughout the problem. The purpose of this test problem is to present a detailed and challenging computation in order to provide evidence for algorithmic strengths and weaknesses in ALEGRA which should be examined further. The results of this work are intended to be used to guide future algorithmic improvements in the spirit of test-driven development processes.
Multi-Level Marketing as a business model
Directory of Open Access Journals (Sweden)
Bogdan Gregor
2013-03-01
Full Text Available Multi Level Marketing is a very popular business model in the Western countries. It is a kind of hybrid of the method of distribution of goods and the method of building a sales network. It is one of the safest (carries a very low risk ways of conducting a business activity. The knowledge about functioning of this business model, both among theoreticians (scanty literature on the subject and practitioners, is still insufficient in Poland. Thus, the presented paper has been prepared as — in the Authors' opinion — it, at least infinitesimally, bridges the gap in the recognition of Multi Level Marketing issues. The aim of the study was, first of all, to describe Multi Level Marketing, to indicate practical benefits of this business model as well as to present basic systems of calculating a commission, which are used in marketing plans of companies. The discussion was based on the study of literature and the knowledge gained in the course of free-form interviews with the leaders of the sector.
Optimal Solution for VLSI Physical Design Automation Using Hybrid Genetic Algorithm
Directory of Open Access Journals (Sweden)
I. Hameem Shanavas
2014-01-01
Full Text Available In Optimization of VLSI Physical Design, area minimization and interconnect length minimization is an important objective in physical design automation of very large scale integration chips. The objective of minimizing the area and interconnect length would scale down the size of integrated chips. To meet the above objective, it is necessary to find an optimal solution for physical design components like partitioning, floorplanning, placement, and routing. This work helps to perform the optimization of the benchmark circuits with the above said components of physical design using hierarchical approach of evolutionary algorithms. The goal of minimizing the delay in partitioning, minimizing the silicon area in floorplanning, minimizing the layout area in placement, minimizing the wirelength in routing has indefinite influence on other criteria like power, clock, speed, cost, and so forth. Hybrid evolutionary algorithm is applied on each of its phases to achieve the objective. Because evolutionary algorithm that includes one or many local search steps within its evolutionary cycles to obtain the minimization of area and interconnect length. This approach combines a hierarchical design like genetic algorithm and simulated annealing to attain the objective. This hybrid approach can quickly produce optimal solutions for the popular benchmarks.
Modular Multi-level converter based HVDC System for Grid Connection of Offshore Wind Power Plant
DEFF Research Database (Denmark)
Gnanarathna, U.N.; Chaudhary, Sanjay Kumar; Gole, A.M.;
2010-01-01
This paper explores the application of modular multi-level converters (MMC) as a means for harnessing the power from off-shore wind power plants. The MMC consists of a large number of simple voltage sourced converter (VSC) submodules that can be easily assembled into a converter for high......-voltage and high power. The paper shows that the MMC converter has a fast response and low harmonic content in comparison with a two-level VSC option. The paper discusses the modeling approach used, including a solution to the modeling challenge imposed by the very large number of switching devices in the MMC....
A Multi Level Multi Domain Method for Particle In Cell Plasma Simulations
Innocenti, M E; Markidis, S; Beck, A; Vapirev, A
2012-01-01
A novel adaptive technique for electromagnetic Particle In Cell (PIC) plasma simulations is presented here. Two main issues are identified in designing adaptive techniques for PIC simulation: first, the choice of the size of the particle shape function in progressively refined grids, with the need to avoid the exertion of self-forces on particles, and, second, the necessity to comply with the strict stability constraints of the explicit PIC algorithm. The adaptive implementation presented responds to these demands with the introduction of a Multi Level Multi Domain (MLMD) system (where a cloud of self-similar domains is fully simulated with both fields and particles) and the use of an Implicit Moment PIC method as baseline algorithm for the adaptive evolution. Information is exchanged between the levels with the projection of the field information from the refined to the coarser levels and the interpolation of the boundary conditions for the refined levels from the coarser level fields. Particles are bound to...
Ozcan, H. Kurtulus; Bilgili, Erdem; Sahin, Ulku; Ucan, O. Nuri; Bayat, Cuma
2007-09-01
Tropospheric ozone concentrations, which are an important air pollutant, are modeled by the use of an artificial intelligence structure. Data obtained from air pollution measurement stations in the city of Istanbul are utilized in constituting the model. A supervised algorithm for the evaluation of ozone concentration using a genetically trained multi-level cellular neural network (ML-CNN) is introduced, developed, and applied to real data. A genetic algorithm is used in the optimization of CNN templates. The model results and the actual measurement results are compared and statistically evaluated. It is observed that seasonal changes in ozone concentrations are reflected effectively by the concentrations estimated by the multilevel-CNN model structure, with a correlation value of 0.57 ascertained between actual and model results. It is shown that the multilevel-CNN modeling technique is as satisfactory as other modeling techniques in associating the data in a complex medium in air pollution applications.
Institute of Scientific and Technical Information of China (English)
H. Kurtulus OZCAN; Erdem BILGILI; Ulku SAHIN; O. Nuri UCAN; Cuma BAYAT
2007-01-01
Tropospheric ozone concentrations, which are an important air pollutant, are modeled by the use of an artificial intelligence structure. Data obtained from air pollution measurement stations in the city of Istanbul are utilized in constituting the model. A supervised algorithm for the evaluation of ozone concentration using a genetically trained multi-level cellular neural network (ML-CNN) is introduced, developed, and applied to real data. A genetic algorithm is used in the optimization of CNN templates. The model results and the actual measurement results are compared and statistically evaluated. It is observed that seasonal changes in ozone concentrations are reflected effectively by the concentrations estimated by the multilevel-CNN model structure, with a correlation value of 0.57 ascertained between actual and model results. It is shown that the multilevel-CNN modeling technique is as satisfactory as other modeling techniques in associating the data in a complex medium in air pollution applications.
Application of Harmony Search algorithm to the solution of groundwater management models
Tamer Ayvaz, M.
2009-06-01
This study proposes a groundwater resources management model in which the solution is performed through a combined simulation-optimization model. A modular three-dimensional finite difference groundwater flow model, MODFLOW is used as the simulation model. This model is then combined with a Harmony Search (HS) optimization algorithm which is based on the musical process of searching for a perfect state of harmony. The performance of the proposed HS based management model is tested on three separate groundwater management problems: (i) maximization of total pumping from an aquifer (steady-state); (ii) minimization of the total pumping cost to satisfy the given demand (steady-state); and (iii) minimization of the pumping cost to satisfy the given demand for multiple management periods (transient). The sensitivity of HS algorithm is evaluated by performing a sensitivity analysis which aims to determine the impact of related solution parameters on convergence behavior. The results show that HS yields nearly same or better solutions than the previous solution methods and may be used to solve management problems in groundwater modeling.
A new algorithm of ionospheric tomography——two-step solution
Wen, Debao
The inherent non-ideal geometry of ground-based global navigation satellite system (GNSS) observation stations distribution results in limited-angle tomographic inverse problems that are ill-posed. To cope with the above problem, a new tomographic algorithm, which is called two-step solution (TSS), is presented in this paper. In the new method, the electron density can be estimated by using two steps: 1) Phillips smoothing method (PSM) is first used to resolve the ill-posed problem in ionospheric tomography system; 2) The "coarse" solution of PSM is then input as the initial value of multiplicative algebraic reconstruction technique (MART) and improved by iterative mode. Numerical simulation experiment demonstrates that the two-step solution is feasible to GNSS-based ionospheric tomography and superior to PSM or MART alone.
Multi-level tree analysis of pulmonary artery/vein trees in non-contrast CT images
Gao, Zhiyun; Grout, Randall W.; Hoffman, Eric A.; Saha, Punam K.
2012-02-01
Diseases like pulmonary embolism and pulmonary hypertension are associated with vascular dystrophy. Identifying such pulmonary artery/vein (A/V) tree dystrophy in terms of quantitative measures via CT imaging significantly facilitates early detection of disease or a treatment monitoring process. A tree structure, consisting of nodes and connected arcs, linked to the volumetric representation allows multi-level geometric and volumetric analysis of A/V trees. Here, a new theory and method is presented to generate multi-level A/V tree representation of volumetric data and to compute quantitative measures of A/V tree geometry and topology at various tree hierarchies. The new method is primarily designed on arc skeleton computation followed by a tree construction based topologic and geometric analysis of the skeleton. The method starts with a volumetric A/V representation as input and generates its topologic and multi-level volumetric tree representations long with different multi-level morphometric measures. A new recursive merging and pruning algorithms are introduced to detect bad junctions and noisy branches often associated with digital geometric and topologic analysis. Also, a new notion of shortest axial path is introduced to improve the skeletal arc joining two junctions. The accuracy of the multi-level tree analysis algorithm has been evaluated using computer generated phantoms and pulmonary CT images of a pig vessel cast phantom while the reproducibility of method is evaluated using multi-user A/V separation of in vivo contrast-enhanced CT images of a pig lung at different respiratory volumes.
The Evolutionary Algorithm to Find Robust Pareto-Optimal Solutions over Time
Directory of Open Access Journals (Sweden)
Meirong Chen
2015-01-01
Full Text Available In dynamic multiobjective optimization problems, the environmental parameters change over time, which makes the true pareto fronts shifted. So far, most works of research on dynamic multiobjective optimization methods have concentrated on detecting the changed environment and triggering the population based optimization methods so as to track the moving pareto fronts over time. Yet, in many real-world applications, it is not necessary to find the optimal nondominant solutions in each dynamic environment. To solve this weakness, a novel method called robust pareto-optimal solution over time is proposed. It is in fact to replace the optimal pareto front at each time-varying moment with the series of robust pareto-optimal solutions. This means that each robust solution can fit for more than one time-varying moment. Two metrics, including the average survival time and average robust generational distance, are present to measure the robustness of the robust pareto solution set. Another contribution is to construct the algorithm framework searching for robust pareto-optimal solutions over time based on the survival time. Experimental results indicate that this definition is a more practical and time-saving method of addressing dynamic multiobjective optimization problems changing over time.
Directory of Open Access Journals (Sweden)
Nilson C. Roberty
2011-01-01
Full Text Available We introduce algorithms marching over a polygonal mesh with elements consistent with the propagation directions of the particle (radiation flux. The decision for adopting this kind of mesh to solve the one-speed Boltzmann transport equation is due to characteristics of the domain of the transport operator which controls derivatives only in the direction of propagation of the particles (radiation flux in the absorbing and scattering media. This a priori adaptivity has the advantages that it formulates a consistent scheme which makes appropriate the application of the Lax equivalence theorem framework to the problem. In this work, we present the main functional spaces involved in the formalism and a description of the algorithms for the mesh generation and the transport equation solution. Some numerical examples related to the solution of a transmission problem in a high-contrast model with absorption and scattering are presented. Also, a comparison with benchmarks problems for source and reactor criticality simulations shows the compatibility between calculations with the algorithms proposed here and theoretical results.
A solution algorithm for fluid-particle flows across all flow regimes
Kong, Bo; Fox, Rodney O.
2017-09-01
Many fluid-particle flows occurring in nature and in technological applications exhibit large variations in the local particle volume fraction. For example, in circulating fluidized beds there are regions where the particles are close-packed as well as very dilute regions where particle-particle collisions are rare. Thus, in order to simulate such fluid-particle systems, it is necessary to design a flow solver that can accurately treat all flow regimes occurring simultaneously in the same flow domain. In this work, a solution algorithm is proposed for this purpose. The algorithm is based on splitting the free-transport flux solver dynamically and locally in the flow. In close-packed to moderately dense regions, a hydrodynamic solver is employed, while in dilute to very dilute regions a kinetic-based finite-volume solver is used in conjunction with quadrature-based moment methods. To illustrate the accuracy and robustness of the proposed solution algorithm, it is implemented in OpenFOAM for particle velocity moments up to second order, and applied to simulate gravity-driven, gas-particle flows exhibiting cluster-induced turbulence. By varying the average particle volume fraction in the flow domain, it is demonstrated that the flow solver can handle seamlessly all flow regimes present in fluid-particle flows.
CMT: a constrained multi-level thresholding approach for ChIP-Seq data analysis.
Directory of Open Access Journals (Sweden)
Iman Rezaeian
Full Text Available Genome-wide profiling of DNA-binding proteins using ChIP-Seq has emerged as an alternative to ChIP-chip methods. ChIP-Seq technology offers many advantages over ChIP-chip arrays, including but not limited to less noise, higher resolution, and more coverage. Several algorithms have been developed to take advantage of these abilities and find enriched regions by analyzing ChIP-Seq data. However, the complexity of analyzing various patterns of ChIP-Seq signals still needs the development of new algorithms. Most current algorithms use various heuristics to detect regions accurately. However, despite how many formulations are available, it is still difficult to accurately determine individual peaks corresponding to each binding event. We developed Constrained Multi-level Thresholding (CMT, an algorithm used to detect enriched regions on ChIP-Seq data. CMT employs a constraint-based module that can target regions within a specific range. We show that CMT has higher accuracy in detecting enriched regions (peaks by objectively assessing its performance relative to other previously proposed peak finders. This is shown by testing three algorithms on the well-known FoxA1 Data set, four transcription factors (with a total of six antibodies for Drosophila melanogaster and the H3K4ac antibody dataset.
Antecedents of Organisational Creativity: A Multi-Level Approach
Directory of Open Access Journals (Sweden)
Ritu Gupta
2016-06-01
Full Text Available The purpose of this literature review is to provide a better understanding of the antecedents of organisational creativity with a multi-level approach. Organisational creativity is a sum total of the creativity accounted for by the individual employees of the organisation, the cumulative creativity of a team or group and creativity arising out of different structural components of an organisation. Some of the antecedents identified from the literature include personality, intrinsic motivation, group cohesion, social inhibition, cognitive interference, leader member exchange, organisational culture and climate, amongst others at individual, group and organisational level. Based on the literature review, suggestions for future research and research propositions have been proposed.
Detecting bots using multi-level traffic analysis
DEFF Research Database (Denmark)
Stevanovic, Matija; Pedersen, Jens Myrup
2016-01-01
Botnets, as networks of compromised “zombie” computers, represent one of the most serious security threats on the Internet today. This paper explores how machines compromised with bot malware can be identified at local and enterprise networks in accurate and time-efficient manner. The paper...... introduces a novel multi-level botnet detection approach that performs network traffic analysis of three protocols widely considered as the main carriers of botnet Command and Control (C&C) and attack traffic, i.e. TCP, UDP and DNS. The proposed method relies on supervised machine learning for identifying...
Fast Algorithm of Numerical Solutions for Strong Nonlinear Partial Differential Equations
Directory of Open Access Journals (Sweden)
Tongjing Liu
2014-07-01
Full Text Available Because of a high mobility ratio in the chemical and gas flooding for oil reservoirs, the problems of numerical dispersion and low calculation efficiency also exist in the common methods, such as IMPES and adaptive implicit methods. Therefore, the original calculation process, “one-step calculation for pressure and multistep calculation for saturation,” was improved by introducing a velocity item and using the fractional flow in a direction to calculate the saturation. Based on these developments, a new algorithm of numerical solution for “one-step calculation for pressure, one-step calculation for velocity, and multi-step calculation for fractional flow and saturation” was obtained, and the convergence condition for the calculation of saturation was also proposed. The simulation result of a typical theoretical model shows that the nonconvergence occurred for about 6,000 times in the conventional algorithm of IMPES, and a high fluctuation was observed in the calculation steps. However, the calculation step of the fast algorithm was stabilized for 0.5 d, indicating that the fast algorithm can avoid the nonconvergence caused by the saturation that was directly calculated by pressure. This has an important reference value in the numerical simulations of chemical and gas flooding for oil reservoirs.
Energy Technology Data Exchange (ETDEWEB)
Svensson, Urban [Computer-aided Fluid Engineering AB, Norrkoeping (Sweden)
2001-04-01
A particle tracking algorithm, PARTRACK, that simulates transport and dispersion in a sparsely fractured rock is described. The main novel feature of the algorithm is the introduction of multiple particle states. It is demonstrated that the introduction of this feature allows for the simultaneous simulation of Taylor dispersion, sorption and matrix diffusion. A number of test cases are used to verify and demonstrate the features of PARTRACK. It is shown that PARTRACK can simulate the following processes, believed to be important for the problem addressed: the split up of a tracer cloud at a fracture intersection, channeling in a fracture plane, Taylor dispersion and matrix diffusion and sorption. From the results of the test cases, it is concluded that PARTRACK is an adequate framework for simulation of transport and dispersion of a solute in a sparsely fractured rock.
Júdice, Joaquim; Raydan, Marcos; Rosa, Silvério; Santos, Sandra
2008-04-01
This paper is devoted to the eigenvalue complementarity problem (EiCP) with symmetric real matrices. This problem is equivalent to finding a stationary point of a differentiable optimization program involving the Rayleigh quotient on a simplex (Queiroz et al., Math. Comput. 73, 1849-1863, 2004). We discuss a logarithmic function and a quadratic programming formulation to find a complementarity eigenvalue by computing a stationary point of an appropriate merit function on a special convex set. A variant of the spectral projected gradient algorithm with a specially designed line search is introduced to solve the EiCP. Computational experience shows that the application of this algorithm to the logarithmic function formulation is a quite efficient way to find a solution to the symmetric EiCP.
Multi-Level Bitmap Indexes for Flash Memory Storage
Energy Technology Data Exchange (ETDEWEB)
Wu, Kesheng; Madduri, Kamesh; Canon, Shane
2010-07-23
Due to their low access latency, high read speed, and power-efficient operation, flash memory storage devices are rapidly emerging as an attractive alternative to traditional magnetic storage devices. However, tests show that the most efficient indexing methods are not able to take advantage of the flash memory storage devices. In this paper, we present a set of multi-level bitmap indexes that can effectively take advantage of flash storage devices. These indexing methods use coarsely binned indexes to answer queries approximately, and then use finely binned indexes to refine the answers. Our new methods read significantly lower volumes of data at the expense of an increased disk access count, thus taking full advantage of the improved read speed and low access latency of flash devices. To demonstrate the advantage of these new indexes, we measure their performance on a number of storage systems using a standard data warehousing benchmark called the Set Query Benchmark. We observe that multi-level strategies on flash drives are up to 3 times faster than traditional indexing strategies on magnetic disk drives.
Multi-Level Bitmap Indexes for Flash Memory Storage
Energy Technology Data Exchange (ETDEWEB)
Wu, Kesheng; Madduri, Kamesh; Canon, Shane
2010-07-23
Due to their low access latency, high read speed, and power-efficient operation, flash memory storage devices are rapidly emerging as an attractive alternative to traditional magnetic storage devices. However, tests show that the most efficient indexing methods are not able to take advantage of the flash memory storage devices. In this paper, we present a set of multi-level bitmap indexes that can effectively take advantage of flash storage devices. These indexing methods use coarsely binned indexes to answer queries approximately, and then use finely binned indexes to refine the answers. Our new methods read significantly lower volumes of data at the expense of an increased disk access count, thus taking full advantage of the improved read speed and low access latency of flash devices. To demonstrate the advantage of these new indexes, we measure their performance on a number of storage systems using a standard data warehousing benchmark called the Set Query Benchmark. We observe that multi-level strategies on flash drives are up to 3 times faster than traditional indexing strategies on magnetic disk drives.
On decoding of multi-level MPSK modulation codes
Lin, Shu; Gupta, Alok Kumar
1990-01-01
The decoding problem of multi-level block modulation codes is investigated. The hardware design of soft-decision Viterbi decoder for some short length 8-PSK block modulation codes is presented. An effective way to reduce the hardware complexity of the decoder by reducing the branch metric and path metric, using a non-uniform floating-point to integer mapping scheme, is proposed and discussed. The simulation results of the design are presented. The multi-stage decoding (MSD) of multi-level modulation codes is also investigated. The cases of soft-decision and hard-decision MSD are considered and their performance are evaluated for several codes of different lengths and different minimum squared Euclidean distances. It is shown that the soft-decision MSD reduces the decoding complexity drastically and it is suboptimum. The hard-decision MSD further simplifies the decoding while still maintaining a reasonable coding gain over the uncoded system, if the component codes are chosen properly. Finally, some basic 3-level 8-PSK modulation codes using BCH codes as component codes are constructed and their coding gains are found for hard decision multistage decoding.
Optimal control of multi-level quantum systems
Energy Technology Data Exchange (ETDEWEB)
Fisher, Robert M.
2010-12-02
This thesis is concerned with the control of quantum systems. Given a Hamiltonian model of a quantum system, we are interested in finding controls - typically shaped electromagnetic pulses - that steer the evolution of the system toward a desired target operation. For this we employ a numerical optimisation method known as the GRAPE algorithm. For particular experimental systems, we design control schemes that respect constraints of robustness and addressability, and are within the reach of the experimental hardware. A general procedure is given for specifying a Hamiltonian model of a driven N-level system and converting it to an appropriate rotating frame. This is then applied together with the numerical algorithm to design improved schemes for two different systems, where laser fields manipulate orbital and hyperfine states of Pr{sup 3+} and Rb. The generation of cluster states in Ising-coupled systems is also studied. We find that, in the ideal case, the solution of evolving only under the coupling Hamiltonian is not time-optimal. This surprising result is in contrast to the known cases for unitary gates. For a symmetrised three-qubit example, we provide a geometrical interpretation of this. Numerically optimised control schemes are then developed for a nonideal coupling topology, modelling an experimental configuration of trapped ions. Controls for the implementation of the two-qubit Deutsch and Grover algorithms are designed for a pair of {sup 13}C nuclear spins at a nitrogen vacancy center in diamond. These implementations are robust to experimental errors, and found to be reproduced with high accuracy on a VFG-150 pulse generator. We also consider two-qubit gate synthesis in a system of superconducting qubits coupled by microwave resonators known as the cavity grid. We find that the optimised schemes allow two-qubit operations to be performed between an arbitrary qubit pair on the grid with only a small time overhead, with speedups of 2-4 over the existing
Adachi, Kohei
2013-01-01
Rubin and Thayer ("Psychometrika," 47:69-76, 1982) proposed the EM algorithm for exploratory and confirmatory maximum likelihood factor analysis. In this paper, we prove the following fact: the EM algorithm always gives a proper solution with positive unique variances and factor correlations with absolute values that do not exceed one,…
Adachi, Kohei
2013-01-01
Rubin and Thayer ("Psychometrika," 47:69-76, 1982) proposed the EM algorithm for exploratory and confirmatory maximum likelihood factor analysis. In this paper, we prove the following fact: the EM algorithm always gives a proper solution with positive unique variances and factor correlations with absolute values that do not exceed one,…
Directory of Open Access Journals (Sweden)
Eman Ali Hussain
2015-01-01
Full Text Available Absract In this project A new method for solving Stochastic Differential Equations SDEs deriving by Wiener process numerically will be construct and implement using Accelerated Genetic Algorithm AGA. An SDE is a differential equation in which one or more of the terms and hence the solutions itself is a stochastic process. Solving stochastic differential equations requires going away from the recognizable deterministic setting of ordinary and partial differential equations into a world where the evolution of a quantity has an inherent random component and where the expected behavior of this quantity can be described in terms of probability distributions. We applied our method on the Ito formula which is equivalent to the SDE to find approximation solution of the SDEs. Numerical experiments illustrate the behavior of the proposed method.
Design of attitude solution algorithm for tail-sitter VTOL UAV
Directory of Open Access Journals (Sweden)
Donghui LIU
2016-02-01
Full Text Available The tail-sitter Vertical Takeoff and Landing (VTOL Unmanned Aerial Vehicle(UAV, flying in a fixed-wing model, overcomes many shortcomings of traditional fixed-wing UAVs, and inherits the advantage of high overall efficiency, which means it has great development potential and very broad application prospects. The attitude of tail-sitter VTOL UAV shows a wide change range in its takeoff and landing stages, and when the attitude sensor changes more than 90 degrees in pitch direction, the Euler angles converted by the Quaternions will have singular points, which means gimbal deadlock appears. From the solution algorithm, this paper provides a method of changing the order of rotation to avoid the appearance of singular points. The results show that this method can be well applied to the attitude solution of the VTOL UAV.
Introduction of Parallel GPGPU Acceleration Algorithms for the Solution of Radiative Transfer
Godoy, William F.; Liu, Xu
2011-01-01
General-purpose computing on graphics processing units (GPGPU) is a recent technique that allows the parallel graphics processing unit (GPU) to accelerate calculations performed sequentially by the central processing unit (CPU). To introduce GPGPU to radiative transfer, the Gauss-Seidel solution of the well-known expressions for 1-D and 3-D homogeneous, isotropic media is selected as a test case. Different algorithms are introduced to balance memory and GPU-CPU communication, critical aspects of GPGPU. Results show that speed-ups of one to two orders of magnitude are obtained when compared to sequential solutions. The underlying value of GPGPU is its potential extension in radiative solvers (e.g., Monte Carlo, discrete ordinates) at a minimal learning curve.
A Multi-level Security Mechanism for Secure Data Transmission in SCTP
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P. Venkadesh
2014-03-01
Full Text Available In this study we propose a multi-level security mechanism to provide secure data transmission in Stream Control Transmission Protocol (SCTP. During the time of TCP/IP protocols the computers were single-homed and nowadays there is a need for mobility, therefore new protocols were designed to support the mobility and multi-homing facilities. SCTP is a newly designed protocol that supports more interesting features such as Multi-homing and Multi-streaming when compared to the existing protocols. Since SCTP is designed for telecommunication its native design does not consider the security issues for data transmission. In this study we analyzed and identified the possibility places for hiding and exchanging of secret information in SCTP and proposed a dynamic encryption algorithm to provide a secure end-to-end data transmission between two nodes by altering the basic structure of the existing SCTP multi-homed protocol so that the attacker does not know the algorithm used since the algorithm is dynamic and the key for the encryption algorithm is hidden in the heartbeat signal of the SCTP and also suggest a method to detect the hacker incase of any attacks against the transmitted packets and finds an alternate path to transmit the remaining packets using the multi-homing options of SCTP.
Directory of Open Access Journals (Sweden)
Annabelle Littoz-Monnet
2010-04-01
Full Text Available This article aims to fill a gap in the theoretical literature on European integration by providing a dynamic and multi-level explanatory framework of the dynamics of European integration – defined as the locus of governance shifts from the national to the European level. While with the development of governance approaches, the multi-actorness of the EU has been taken into account, the objective of understanding how interactions between different actors explain dynamics of integration has been abandoned. Thus, the article shows that by focusing on dynamic patterns of interaction between subnational, state and supranational actors, some core dynamics of the European integration process can be better captured. A dynamic and multi-level model of interaction, termed ‘reversed intergovernmentalism’, is proposed here. The model posits that governments’ intervention at the EU level often takes place as a reaction to developments orchestrated by Community institutions, but that, through their reaction, states in turn foster both the process of integration and another form of EU intervention in such a way that the very nature of EU integration can also divert from initial EU agendas. Setting itself against existing theories of European integration, the argument shows that integration dynamics can only be fully understood within a process of interaction and reciprocal feedback between actors at different levels of governance.
Optimization of the K-means algorithm for the solution of high dimensional instances
Pérez, Joaquín; Pazos, Rodolfo; Olivares, Víctor; Hidalgo, Miguel; Ruiz, Jorge; Martínez, Alicia; Almanza, Nelva; González, Moisés
2016-06-01
This paper addresses the problem of clustering instances with a high number of dimensions. In particular, a new heuristic for reducing the complexity of the K-means algorithm is proposed. Traditionally, there are two approaches that deal with the clustering of instances with high dimensionality. The first executes a preprocessing step to remove those attributes of limited importance. The second, called divide and conquer, creates subsets that are clustered separately and later their results are integrated through post-processing. In contrast, this paper proposes a new solution which consists of the reduction of distance calculations from the objects to the centroids at the classification step. This heuristic is derived from the visual observation of the clustering process of K-means, in which it was found that the objects can only migrate to adjacent clusters without crossing distant clusters. Therefore, this heuristic can significantly reduce the number of distance calculations from an object to the centroids of the potential clusters that it may be classified to. To validate the proposed heuristic, it was designed a set of experiments with synthetic and high dimensional instances. One of the most notable results was obtained for an instance of 25,000 objects and 200 dimensions, where its execution time was reduced up to 96.5% and the quality of the solution decreased by only 0.24% when compared to the K-means algorithm.
Management Of Large Scale Osmotic Dehydration Solution Using The Pearsons Square Algorithm
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Oladejo Duduyemi
2015-01-01
Full Text Available ABSTRACT Osmotic dehydration is a widely researched and advantageous pre-treatment process in food preservation but has not enjoyed industrial acceptance because if its highly concentrated and voluminous effluent. The Pearsons square algorithm was employed to give a focussed attack to the problem by developing a user-friendly template for reconstituting effluents for recycling purposes using Java script programme. Outflow from a pilot scale plant was reactivated and introduced into a scheme of operation for continuous OD of fruits and vegetables. Screened and re-concentrated effluent were subjected to statistical analysis in comparison to initial concentrations solution at confidence limit of p0.05. The template proven to be an adequate representation of the Pearsons square algorithm it is sufficiently good in reconstituting used osmotic solutions for repetitive usage. This protocol if adopted in the industry is not only environmentally friendly but also promises significant economic improvement of OD process. Application Recycling of non-reacting media and as a template for automation in continuous OD processing.
Chang, Weng-Long; Ren, Ting-Ting; Feng, Mang
2015-01-01
In this paper, it is shown that the proposed quantum algorithm for implementing Boolean circuits generated from the DNA-based algorithm solving the vertex-cover problem of any graph G with m edges and n vertices is the optimal quantum algorithm. Next, it is also demonstrated that mathematical solutions of the same biomolecular solutions are represented in terms of a unit vector in the finite-dimensional Hilbert space. Furthermore, for testing our theory, a nuclear magnetic resonance (NMR) experiment of three quantum bits to solve the simplest vertex-cover problem is completed.
Automatic Multi-Level Thresholding Segmentation Based on Multi-Objective Optimization
Directory of Open Access Journals (Sweden)
L. DJEROU,
2012-01-01
Full Text Available In this paper, we present a new multi-level image thresholding technique, called Automatic Threshold based on Multi-objective Optimization "ATMO" that combines the flexibility of multi-objective fitness functions with the power of a Binary Particle Swarm Optimization algorithm "BPSO", for searching the "optimum" number of the thresholds and simultaneously the optimal thresholds of three criteria: the between-class variances criterion, the minimum error criterion and the entropy criterion. Some examples of test images are presented to compare our segmentation method, based on the multi-objective optimization approach with Otsu’s, Kapur’s and Kittler’s methods. Our experimental results show that the thresholding method based on multi-objective optimization is more efficient than the classical Otsu’s, Kapur’s and Kittler’s methods.
Multi-Level Marketing - a Tool of Relationship Marketing
Directory of Open Access Journals (Sweden)
Constantin C.
2009-12-01
Full Text Available This paper aims to analyse the opportunity of using multi-level marketing (MLM as a tool of relationship marketing. The research is firstly based on an analysis regarding the issues about the legality of MLM techniques in the context of EU and US regulation systems. The outcomes of this research stress the main characteristics of legal network marketing and how a person which wants to become independent distributor could avoid the cooperation with an illegal pyramid scheme. The second research is based on a case study at the level of an insurance broker, which emphasizes the benefits that all parties involved in a transaction (broker, distributor and customer could obtain by using an MLM scheme.
PENERAPAN HIRARKI DATA SQL DALAM MULTI LEVEL MARKETING
Directory of Open Access Journals (Sweden)
Sendi Novianto
2012-05-01
Full Text Available Sebagian besar pengguna pada satu waktu pasti pernah berurusan dengan hirarki data dalam database SQL dan tidak diragukan lagi belajar bahwa pengelolaan data hirarkis bukanlah apa yang dimaksudkan oleh database relasional. Tabel database relasional tidaklah hirarkis (seperti XML, tetapi hanya sebuah daftar. Data hirarkis memiliki hubungan parents-child yang tidak biasanya direpresentasikan dalam tabel database relasional. Multi Level Marketing (MLM merupakan suatu strategi pemasaran di mana tenaga penjualan mendapatkan kompensasi tidak hanya untuk penjualan tapi, tetapi juga untuk penjualan orang lain yang mereka rekrut, menciptakan suatu downline distributor dan hirarki dari berbagai tingkat kompensasi. Istilah lainnya untuk MLM termasuk jaringan pemasaran, penjualan dan pemasaran piramida rujukan. Data Hirarki penting di MLM untuk melacak catatan aktivitas penjualan, sehingga mereka dapat termotivasi setiap saat. Kata kunci : MLM, hirarki data, SQL, marketing.
Z - Source Multi Level Inverter Based PV Generation System
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T. Lakhmi kanth
2014-09-01
Full Text Available In this paper a novel technique of Z-Source multilevel Inverter based PV Generation system is implemented and simulated using MATLAB-Simulink simulation software. The Photovoltaic cells are healthier option for converting solar energy into electricity. Due to high capital cost and low efficiency PV cells have not yet been a fully smart choice for electricity users. To enhance the performance of the system, Z-Source multi level inverter can be used in place of conventional Voltage Source Inverter (VSI in Solar Power Generation System. The PV cell model is developed using circuit mathematical equations. The Z-Source multilevel inverter is modeled to realize boosted DC to AC conversion (inversion with low THD. Outcome shows that the energy conversion efficiency of ZSMLI is a lot improved as compared to conventional voltage Source Inverter (VSI. By doing FFT analysis we can know the total THD.
A Multi-Leveled Coordinate for Multibody Mechanics
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Shen Fan
2016-01-01
Full Text Available For a proper way of modelling and simulation, as well as the precise and completeness, and a new multi-level method named homogeneous tensor coordinate(HTC was developed by improving the absolute nodal coordinate formulation(ANCF and the homogeneous coordinates(HC. In HTC, a new form of 2×2 matrix was employed instead of angles, when the capacity of expression and calculation was increased at the same time. HTC has good performance in traditional rigid body mechanics, which especially suitable for multibody modelling. Therefore, the robotic engineering may benefit from this finding, and a new formulation for scientific research may also affect the physics although some mathematical problems are raised in matrix theory.
Multi-level spherical moments based 3D model retrieval
Institute of Scientific and Technical Information of China (English)
LIU Wei; HE Yuan-jun
2006-01-01
In this paper a novel 3D model retrieval method that employs multi-level spherical moment analysis and relies on voxelization and spherical mapping of the 3D models is proposed. For a given polygon-soup 3D model, first a pose normalization step is done to align the model into a canonical coordinate frame so as to define the shape representation with respect to this orientation. Afterward we rasterize its exterior surface into cubical voxel grids, then a series of homocentric spheres with their center superposing the center of the voxel grids cut the voxel grids into several spherical images. Finally moments belonging to each sphere are computed and the moments of all spheres constitute the descriptor of the model. Experiments showed that Euclidean distance based on this kind of feature vector can distinguish different 3D models well and that the 3D model retrieval system based on this arithmetic yields satisfactory performance.
Development of the Multi-Level Seismic Receiver (MLSR)
Energy Technology Data Exchange (ETDEWEB)
Sleefe, G.E.; Engler, B.P.; Drozda, P.M.; Franco, R.J.; Morgan, J.
1995-02-01
The Advanced Geophysical Technology Department (6114) and the Telemetry Technology Development Department (2664) have, in conjunction with the Oil Recovery Technology Partnership, developed a Multi-Level Seismic Receiver (MLSR) for use in crosswell seismic surveys. The MLSR was designed and evaluated with the significant support of many industry partners in the oil exploration industry. The unit was designed to record and process superior quality seismic data operating in severe borehole environments, including high temperature (up to 200{degrees}C) and static pressure (10,000 psi). This development has utilized state-of-the-art technology in transducers, data acquisition, and real-time data communication and data processing. The mechanical design of the receiver has been carefully modeled and evaluated to insure excellent signal coupling into the receiver.
Politics of innovation in multi-level water governance systems
Daniell, Katherine A.; Coombes, Peter J.; White, Ian
2014-11-01
Innovations are being proposed in many countries in order to support change towards more sustainable and water secure futures. However, the extent to which they can be implemented is subject to complex politics and powerful coalitions across multi-level governance systems and scales of interest. Exactly how innovation uptake can be best facilitated or blocked in these complex systems is thus a matter of important practical and research interest in water cycle management. From intervention research studies in Australia, China and Bulgaria, this paper seeks to describe and analyse the behind-the-scenes struggles and coalition-building that occurs between water utility providers, private companies, experts, communities and all levels of government in an effort to support or block specific innovations. The research findings suggest that in order to ensure successful passage of the proposed innovations, champions for it are required from at least two administrative levels, including one with innovation implementation capacity, as part of a larger supportive coalition. Higher governance levels can play an important enabling role in facilitating the passage of certain types of innovations that may be in competition with currently entrenched systems of water management. Due to a range of natural biases, experts on certain innovations and disciplines may form part of supporting or blocking coalitions but their evaluations of worth for water system sustainability and security are likely to be subject to competing claims based on different values and expertise, so may not necessarily be of use in resolving questions of "best courses of action". This remains a political values-based decision to be negotiated through the receiving multi-level water governance system.
Thermodynamically Consistent Algorithms for the Solution of Phase-Field Models
Vignal, Philippe
2016-02-11
Phase-field models are emerging as a promising strategy to simulate interfacial phenomena. Rather than tracking interfaces explicitly as done in sharp interface descriptions, these models use a diffuse order parameter to monitor interfaces implicitly. This implicit description, as well as solid physical and mathematical footings, allow phase-field models to overcome problems found by predecessors. Nonetheless, the method has significant drawbacks. The phase-field framework relies on the solution of high-order, nonlinear partial differential equations. Solving these equations entails a considerable computational cost, so finding efficient strategies to handle them is important. Also, standard discretization strategies can many times lead to incorrect solutions. This happens because, for numerical solutions to phase-field equations to be valid, physical conditions such as mass conservation and free energy monotonicity need to be guaranteed. In this work, we focus on the development of thermodynamically consistent algorithms for time integration of phase-field models. The first part of this thesis focuses on an energy-stable numerical strategy developed for the phase-field crystal equation. This model was put forward to model microstructure evolution. The algorithm developed conserves, guarantees energy stability and is second order accurate in time. The second part of the thesis presents two numerical schemes that generalize literature regarding energy-stable methods for conserved and non-conserved phase-field models. The time discretization strategies can conserve mass if needed, are energy-stable, and second order accurate in time. We also develop an adaptive time-stepping strategy, which can be applied to any second-order accurate scheme. This time-adaptive strategy relies on a backward approximation to give an accurate error estimator. The spatial discretization, in both parts, relies on a mixed finite element formulation and isogeometric analysis. The codes are
Integrating R and Java for Enhancing Interactivity of Algorithmic Data Analysis Software Solutions
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Titus Felix FURTUNĂ
2016-06-01
Full Text Available Conceiving software solutions for statistical processing and algorithmic data analysis involves handling diverse data, fetched from various sources and in different formats, and presenting the results in a suggestive, tailorable manner. Our ongoing research aims to design programming technics for integrating R developing environment with Java programming language for interoperability at a source code level. The goal is to combine the intensive data processing capabilities of R programing language, along with the multitude of statistical function libraries, with the flexibility offered by Java programming language and platform, in terms of graphical user interface and mathematical function libraries. Both developing environments are multiplatform oriented, and can complement each other through interoperability. R is a comprehensive and concise programming language, benefiting from a continuously expanding and evolving set of packages for statistical analysis, developed by the open source community. While is a very efficient environment for statistical data processing, R platform lacks support for developing user friendly, interactive, graphical user interfaces (GUIs. Java on the other hand, is a high level object oriented programming language, which supports designing and developing performant and interactive frameworks for general purpose software solutions, through Java Foundation Classes, JavaFX and various graphical libraries. In this paper we treat both aspects of integration and interoperability that refer to integrating Java code into R applications, and bringing R processing sequences into Java driven software solutions. Our research has been conducted focusing on case studies concerning pattern recognition and cluster analysis.
Energy Technology Data Exchange (ETDEWEB)
Nanda, T.; Bijwe, P.R.; Kothari, D.P.
1982-10-01
This paper presents the development of a highly effective piecewise fast developed load flow algorithm which has a promising potential for practical application. The algorithm requires minimal storage which is almost independent of the sytem size thus enabling power flow solutions of large systems being accomplished on available small size computers and microprocessors. The potential of the suggested algorithm for practical application has been demonstrated by obtaining the load flow results for a few sample systems. It is envisaged that the algorithm would immensely appeal to the utility engineers, since the engineer not only needs the minimum memory for solving the problem but also can develop the program with utmost care and confidence since the algorithm is devoid of such programming complexities like sparsity exploitation and optimal ordering inherent with modern load flow programs. It is believed that the algorithm would find great popularity with the utilities.
A robust algorithm for moving interface of multi-material fluids based on Riemann solutions
Institute of Scientific and Technical Information of China (English)
Xueying Zhang; Ning Zhao
2006-01-01
In the paper,the numerical simulation of interface problems for multiple material fluids is studied.The level set function is designed to capture the location of the material interface.For multi-dimensional and multi-material fluids,the modified ghost fluid method needs a Riemann solution to renew the variable states near the interface.Here we present a new convenient and effective algorithm for solving the Riemann problem in the normal direction.The extrapolated variables are populated by Taylor series expansions in the direction.The anti-diffusive high order WENO difference scheme with the limiter is adopted for the numerical simulation.Finally we implement a series of numerical experiments of multi-material flows.The obtained results are satisfying,compared to those by other methods.
Institute of Scientific and Technical Information of China (English)
YAN Shiliang; WANG Yinling
2007-01-01
Travelling Salesman Problem (TSP) is a classical optimization problem and it is one of a class of NP-Problem. The purposes of this work is to apply data mining methodologies to explore the patterns in data generated by an Ant Colony Algorithm (ACA) performing a searching operation and to develop a rule set searcher which approximates the ACA'S searcher. An attribute-oriented induction methodology was used to explore the relationship between an operations' sequence and its attributes and a set of rules has been developed. At the end of this paper, the experimental results have shown that the proposed approach has good performance with respect to the quality of solution and the speed of computation.
Missing values in multi-level simultaneous component analysis
Josse, Julie; Timmerman, Marieke E.; Kiers, Henk A. L.
2013-01-01
Component analysis of data with missing values is often performed with algorithms of iterative imputation. However, this approach is prone to overfitting problems. As an alternative, Josse et al. (2009) proposed a regularized algorithm in the framework of Principal Component Analysis (PCA). Here we
Musharavati, Farayi; Hamouda, Abdelmagid Salem
2015-01-01
Multiple parts process planning (MPPP) is a hard optimization problem that requires the rigor and intensity of metaheuristic-based algorithms such as simulated annealing and genetic algorithms. In this paper, a solution method for this problem is developed based on genetic algorithms. Genetic algorithms solve problems by exploring a given search space. To do this, a landscape over which the search traverses is constructed based on a number of algorithm choices. Key algorithm choices include (...
Experiments of Multi-Level Read-Only Recording Using Readout Signal Wave-Shape Modulation
Institute of Scientific and Technical Information of China (English)
TANG Yi; PEI Jing; PAN Long-Fa; NI Yi; HU Hua; ZHANG Bu-Qing
2008-01-01
An innovative multilevel read-only recording method is proposed.In this method,a short pit/land is deliberately inserted to the original land/pit.This modifies the wave-shape of readout signal.Taking the wave-shape as the symbol of level detection,a signal wave-shape modulation (SWSM) multilevel method is realized.This method is carried out and validated on the DVD read-only manufacture and readout system.A capacity of 15 GB can be expected,and a bit error rate of 10-4 is achieved.The capacity can meet the demand of high definition movie publication.This method also provides a potential multi-level solution for other storage formats and systems.
Multi-level Governance as an Alternative: The Municipality of Barcelona and the Ciutat Refugi Plan
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Ezgi Irgil
2016-12-01
Full Text Available This paper analyses the response of the Municipality of Barcelona to the Syrian refugee crisis in Europe as an alternative solution that challenges the national government’s restrictive approach. This response introduces the Ciutat Refugi Plan with a city-to-city network at the municipal level that involves other European cities in creating safe routes for refugees at the local government level. In line with multi-level governance theory, I argue that central governments’ inaction has pressured local governments to take action during the Syrian refugee influx. Relying on the influence of local government networks, the Municipality of Barcelona uses discourse as a tool of action in opening discursive spaces for humanitarian political responses to the refugee crisis. Using critical discourse analysis, I test this argument by examining in-depth interviews, speeches of people in power that have appeared in news articles, and statements on official websites.
Multi-level molecular modelling for plasma medicine
Bogaerts, Annemie; Khosravian, Narjes; Van der Paal, Jonas; Verlackt, Christof C. W.; Yusupov, Maksudbek; Kamaraj, Balu; Neyts, Erik C.
2016-02-01
Modelling at the molecular or atomic scale can be very useful for obtaining a better insight in plasma medicine. This paper gives an overview of different atomic/molecular scale modelling approaches that can be used to study the direct interaction of plasma species with biomolecules or the consequences of these interactions for the biomolecules on a somewhat longer time-scale. These approaches include density functional theory (DFT), density functional based tight binding (DFTB), classical reactive and non-reactive molecular dynamics (MD) and united-atom or coarse-grained MD, as well as hybrid quantum mechanics/molecular mechanics (QM/MM) methods. Specific examples will be given for three important types of biomolecules, present in human cells, i.e. proteins, DNA and phospholipids found in the cell membrane. The results show that each of these modelling approaches has its specific strengths and limitations, and is particularly useful for certain applications. A multi-level approach is therefore most suitable for obtaining a global picture of the plasma-biomolecule interactions.
Multi-level segment analysis: definition and applications in turbulence
Wang, Lipo
2015-11-01
The interaction of different scales is among the most interesting and challenging features in turbulence research. Existing approaches used for scaling analysis such as structure-function and Fourier spectrum method have their respective limitations, for instance scale mixing, i.e. the so-called infrared and ultraviolet effects. For a given function, by specifying different window sizes, the local extremal point set will be different. Such window size dependent feature indicates multi-scale statistics. A new method, multi-level segment analysis (MSA) based on the local extrema statistics, has been developed. The part of the function between two adjacent extremal points is defined as a segment, which is characterized by the functional difference and scale difference. The structure function can be differently derived from these characteristic parameters. Data test results show that MSA can successfully reveal different scaling regimes in turbulence systems such as Lagrangian and two-dimensional turbulence, which have been remaining controversial in turbulence research. In principle MSA can generally be extended for various analyses.
Evolution of neuroarchitecture, multi-level analyses and calibrative reductionism.
Berntson, Gary G; Norman, Greg J; Hawkley, Louise C; Cacioppo, John T
2012-02-06
Evolution has sculpted the incredibly complex human nervous system, among the most complex functions of which extend beyond the individual to an intricate social structure. Although these functions are deterministic, those determinants are legion, heavily interacting and dependent on a specific evolutionary trajectory. That trajectory was directed by the adaptive significance of quasi-random genetic variations, but was also influenced by chance and caprice. With a different evolutionary pathway, the same neural elements could subserve functions distinctly different from what they do in extant human brains. Consequently, the properties of higher level neural networks cannot be derived readily from the properties of the lower level constituent elements, without studying these elements in the aggregate. Thus, a multi-level approach to integrative neuroscience may offer an optimal strategy. Moreover, the process of calibrative reductionism, by which concepts and understandings from one level of organization or analysis can mutually inform and 'calibrate' those from other levels (both higher and lower), may represent a viable approach to the application of reductionism in science. This is especially relevant in social neuroscience, where the basic subject matter of interest is defined by interacting organisms across diverse environments.
Developing Multi-Level Institutions from Top-Down Ancestors
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Martha Dowsley
2007-11-01
Full Text Available The academic literature contains numerous examples of the failures of both top-down and bottom-up common pool resource management frameworks. Many authors agree that management regimes instead need to utilize a multi-level governance approach to meet diverse objectives in management. However, many currently operating systems do not have that history. This paper explores the conversion of ancestral top-down regimes to complex systems involving multiple scales, levels and objectives through the management of the polar bear (Ursus maritimus in its five range countries. The less successful polar bear management systems continue to struggle with the challenges of developing institutions with the capacity to learn and change, addressing multiple objectives while recognizing the conservation backbone to management, and matching the institutional scale with biophysical, economic and social scales. The comparatively successful institutions incorporate these features, but reveal on-going problems with vertical links that are partially dealt with through the creation of links to other groups.
Multi-level and hybrid modelling approaches for systems biology.
Bardini, R; Politano, G; Benso, A; Di Carlo, S
2017-01-01
During the last decades, high-throughput techniques allowed for the extraction of a huge amount of data from biological systems, unveiling more of their underling complexity. Biological systems encompass a wide range of space and time scales, functioning according to flexible hierarchies of mechanisms making an intertwined and dynamic interplay of regulations. This becomes particularly evident in processes such as ontogenesis, where regulative assets change according to process context and timing, making structural phenotype and architectural complexities emerge from a single cell, through local interactions. The information collected from biological systems are naturally organized according to the functional levels composing the system itself. In systems biology, biological information often comes from overlapping but different scientific domains, each one having its own way of representing phenomena under study. That is, the different parts of the system to be modelled may be described with different formalisms. For a model to have improved accuracy and capability for making a good knowledge base, it is good to comprise different system levels, suitably handling the relative formalisms. Models which are both multi-level and hybrid satisfy both these requirements, making a very useful tool in computational systems biology. This paper reviews some of the main contributions in this field.
PELAKSANAAN JUAL BELI MELALUI SISTEM MULTI LEVEL MARKETING PERSPEKTIF HUKUM ISLAM
Directory of Open Access Journals (Sweden)
Ayu Dewi Utami
2016-03-01
Full Text Available Bisnis Multi Level Marketing (MLM cukup berperan dalam menggerakkan roda perekonomian masyarakat. Dalam sejumlah kasus, Multi Level Marketing (MLM kerap dijadikan kedok dari bisnis money game dan mendewakan passive income. Bertolak dari kasus kasus seperti itulah, Majelis Ulama Indonesia (MUI telah menggodok prinsip-prinsip bisnis ini secara syariah termasuk marketing plannya. Tujuannya untuk melindungi pengusaha dan mitra bisnisnya (masyarakat dari praktik bisnis yang haram atau syubhat. Dari prinsip-prinsip yang ditentukan oleh Majelis Ulama Indonesia (MUI, peneliti mengadakan penelitian ini dengan tujuan untuk mengetahui bagaimana mekanisme bisnis Multi Level Marketing (MLM, serta untuk mengetahui bagaimana bisnis Multi Level Marketing (MLM menurut hukum Islam. Metode yang digunakan dalam penelitian ini adalah menggunakan metode pendekatan yuridis normatif, spesifikasi penelitian yang digunakan adalah deskriptif analitis, sedangkan penentuan sampel menggunakan metode Non Random sampling. Alat penelitian meliputi studi kepustakaan dan wawancara. Metode analisis data dilakukan dengan analisis kualitatif. Ada dua aspek untuk menilai apakah bisnis Multi Level Marketing (MLM itu sesuai dengan syariah atau tidak, yaitu aspek produk atau jasa yang dijual dan sistem dari Multi Level Marketing (MLM itu sendiri. Bagaimana sistem pemberian bonus yang terdapat dalam perusahaan Multi Level Marketing (MLM apakah terbebas dari unsus garar maupun maisir. Penelitian ini bertujuan untuk mengkaji lebih dalam tentang Multi Level Marketing (MLM khususnya dalam Hukum Islam. Sisi negatif yang terdapat pada sistem Multi Level Marketing (MLM tidak mewakili keharaman secara keseluruhan terhadap bisnis yang berbasis Multi Level Marketing (MLM lainnya.
Development of Gis Tool for the Solution of Minimum Spanning Tree Problem using Prim's Algorithm
Dutta, S.; Patra, D.; Shankar, H.; Alok Verma, P.
2014-11-01
minimum spanning tree (MST) of a connected, undirected and weighted network is a tree of that network consisting of all its nodes and the sum of weights of all its edges is minimum among all such possible spanning trees of the same network. In this study, we have developed a new GIS tool using most commonly known rudimentary algorithm called Prim's algorithm to construct the minimum spanning tree of a connected, undirected and weighted road network. This algorithm is based on the weight (adjacency) matrix of a weighted network and helps to solve complex network MST problem easily, efficiently and effectively. The selection of the appropriate algorithm is very essential otherwise it will be very hard to get an optimal result. In case of Road Transportation Network, it is very essential to find the optimal results by considering all the necessary points based on cost factor (time or distance). This paper is based on solving the Minimum Spanning Tree (MST) problem of a road network by finding it's minimum span by considering all the important network junction point. GIS technology is usually used to solve the network related problems like the optimal path problem, travelling salesman problem, vehicle routing problems, location-allocation problems etc. Therefore, in this study we have developed a customized GIS tool using Python script in ArcGIS software for the solution of MST problem for a Road Transportation Network of Dehradun city by considering distance and time as the impedance (cost) factors. It has a number of advantages like the users do not need a greater knowledge of the subject as the tool is user-friendly and that allows to access information varied and adapted the needs of the users. This GIS tool for MST can be applied for a nationwide plan called Prime Minister Gram Sadak Yojana in India to provide optimal all weather road connectivity to unconnected villages (points). This tool is also useful for constructing highways or railways spanning several
SOLA-DM: A numerical solution algorithm for transient three-dimensional flows
Energy Technology Data Exchange (ETDEWEB)
Wilson, T.L.; Nichols, B.D.; Hirt, C.W.; Stein, L.R.
1988-02-01
SOLA-DM is a three-dimensional time-explicit, finite-difference, Eulerian, fluid-dynamics computer code for solving the time-dependent incompressible Navier-Stokes equations. The solution algorithm (SOLA) evolved from the marker-and-cell (MAC) method, and the code is highly vectorized for efficient performance on a Cray computer. The computational domain is discretized by a mesh of parallelepiped cells in either cartesian or cylindrical geometry. The primary hydrodynamic variables for approximating the solution of the momentum equations are cell-face-centered velocity components and cell-centered pressures. Spatial accuracy is selected by the user to be first or second order; the time differencing is first-order accurate. The incompressibility condition results in an elliptic equation for pressure that is solved by a conjugate gradient method. Boundary conditions of five general types may be chosen: free-slip, no-slip, continuative, periodic, and specified pressure. In addition, internal mesh specifications to model obstacles and walls are provided. SOLA-DM also solves the equations for discrete particle dynamics, permitting the transport of marker particles or other solid particles through the fluid to be modeled. 7 refs., 7 figs.
Energy Technology Data Exchange (ETDEWEB)
Nanda, J.; Bijwe, P.R.; Kothari, D.P.
1982-10-01
A highly effective piecewise fast developed load flow algorithm has been developed which has a promising potential for practical application. The algorithm requires minimal storage which is almost independent of the systems size thus enabling power flow solutions of large systems being accomplished on available small size computers and microprocessors. The potential of the suggested algorithm for practical applications has been demonstrated by obtaining the load flow results for a few sample systems. It is envisaged that the algorithm would immensely appeal to utility engineers who not only need the minimum memory for solving the problem but also can develop the program with utmost care and confidence since the algorithm i devoid of such programming complexities like sparsity exploitation and optimal ordering inherent with modern load programs.
Energy Technology Data Exchange (ETDEWEB)
Bagheri, Saman; Nikkar, Ali [University of Tabriz, Tabriz (Iran, Islamic Republic of)
2014-11-15
This paper deals with the determination of approximate solutions for a model of column buckling using two efficient and powerful methods called He's variational approach and variational iteration algorithm-II. These methods are used to find analytical approximate solution of nonlinear dynamic equation of a model for the column buckling. First and second order approximate solutions of the equation of the system are achieved. To validate the solutions, the analytical results have been compared with those resulted from Runge-Kutta 4th order method. A good agreement of the approximate frequencies and periodic solutions with the numerical results and the exact solution shows that the present methods can be easily extended to other nonlinear oscillation problems in engineering. The accuracy and convenience of the proposed methods are also revealed in comparisons with the other solution techniques.
Antibiotic resistance shaping multi-level population biology of bacteria.
Baquero, Fernando; Tedim, Ana P; Coque, Teresa M
2013-01-01
Antibiotics have natural functions, mostly involving cell-to-cell signaling networks. The anthropogenic production of antibiotics, and its release in the microbiosphere results in a disturbance of these networks, antibiotic resistance tending to preserve its integrity. The cost of such adaptation is the emergence and dissemination of antibiotic resistance genes, and of all genetic and cellular vehicles in which these genes are located. Selection of the combinations of the different evolutionary units (genes, integrons, transposons, plasmids, cells, communities and microbiomes, hosts) is highly asymmetrical. Each unit of selection is a self-interested entity, exploiting the higher hierarchical unit for its own benefit, but in doing so the higher hierarchical unit might acquire critical traits for its spread because of the exploitation of the lower hierarchical unit. This interactive trade-off shapes the population biology of antibiotic resistance, a composed-complex array of the independent "population biologies." Antibiotics modify the abundance and the interactive field of each of these units. Antibiotics increase the number and evolvability of "clinical" antibiotic resistance genes, but probably also many other genes with different primary functions but with a resistance phenotype present in the environmental resistome. Antibiotics influence the abundance, modularity, and spread of integrons, transposons, and plasmids, mostly acting on structures present before the antibiotic era. Antibiotics enrich particular bacterial lineages and clones and contribute to local clonalization processes. Antibiotics amplify particular genetic exchange communities sharing antibiotic resistance genes and platforms within microbiomes. In particular human or animal hosts, the microbiomic composition might facilitate the interactions between evolutionary units involved in antibiotic resistance. The understanding of antibiotic resistance implies expanding our knowledge on multi-level
Design of a Multi-Level/Analog Ferroelectric Memory Device
MacLeod, Todd C.; Phillips, Thomas A.; Ho, Fat D.
2006-01-01
Increasing the memory density and utilizing the dove1 characteristics of ferroelectric devices is important in making ferroelectric memory devices more desirable to the consumer. This paper describes a design that allows multiple levels to be stored in a ferroelectric based memory cell. It can be used to store multiple bits or analog values in a high speed nonvolatile memory. The design utilizes the hysteresis characteristic of ferroelectric transistors to store an analog value in the memory cell. The design also compensates for the decay of the polarization of the ferroelectric material over time. This is done by utilizing a pair of ferroelectric transistors to store the data. One transistor is used as a reference to determine the amount of decay that has occurred since the pair was programmed. The second transistor stores the analog value as a polarization value between zero and saturated. The design allows digital data to be stored as multiple bits in each memory cell. The number of bits per cell that can be stored will vary with the decay rate of the ferroelectric transistors and the repeatability of polarization between transistors. It is predicted that each memory cell may be able to store 8 bits or more. The design is based on data taken from actual ferroelectric transistors. Although the circuit has not been fabricated, a prototype circuit is now under construction. The design of this circuit is different than multi-level FLASH or silicon transistor circuits. The differences between these types of circuits are described in this paper. This memory design will be useful because it allows higher memory density, compensates for the environmental and ferroelectric aging processes, allows analog values to be directly stored in memory, compensates for the thermal and radiation environments associated with space operations, and relies only on existing technologies.
Design of a Multi-Level/Analog Ferroelectric Memory Device
MacLeod, Todd C.; Phillips, Thomas A.; Ho, Fat D.
2006-01-01
Increasing the memory density and utilizing the dove1 characteristics of ferroelectric devices is important in making ferroelectric memory devices more desirable to the consumer. This paper describes a design that allows multiple levels to be stored in a ferroelectric based memory cell. It can be used to store multiple bits or analog values in a high speed nonvolatile memory. The design utilizes the hysteresis characteristic of ferroelectric transistors to store an analog value in the memory cell. The design also compensates for the decay of the polarization of the ferroelectric material over time. This is done by utilizing a pair of ferroelectric transistors to store the data. One transistor is used as a reference to determine the amount of decay that has occurred since the pair was programmed. The second transistor stores the analog value as a polarization value between zero and saturated. The design allows digital data to be stored as multiple bits in each memory cell. The number of bits per cell that can be stored will vary with the decay rate of the ferroelectric transistors and the repeatability of polarization between transistors. It is predicted that each memory cell may be able to store 8 bits or more. The design is based on data taken from actual ferroelectric transistors. Although the circuit has not been fabricated, a prototype circuit is now under construction. The design of this circuit is different than multi-level FLASH or silicon transistor circuits. The differences between these types of circuits are described in this paper. This memory design will be useful because it allows higher memory density, compensates for the environmental and ferroelectric aging processes, allows analog values to be directly stored in memory, compensates for the thermal and radiation environments associated with space operations, and relies only on existing technologies.
Bittig, Arne; Uhrmacher, Adelinde
2016-08-03
Spatio-temporal dynamics of cellular processes can be simulated at different levels of detail, from (deterministic) partial differential equations via the spatial Stochastic Simulation algorithm to tracking Brownian trajectories of individual particles. We present a spatial simulation approach for multi-level rule-based models, which includes dynamically hierarchically nested cellular compartments and entities. Our approach ML-Space combines discrete compartmental dynamics, stochastic spatial approaches in discrete space, and particles moving in continuous space. The rule-based specification language of ML-Space supports concise and compact descriptions of models and to adapt the spatial resolution of models easily.
Novel Genetic Algorithm Based Solutions for Optimal Power Flow under Contingency Conditions
Directory of Open Access Journals (Sweden)
S. V. Durga Bhavani,
2014-06-01
Full Text Available Power system throughout the world is undergoing tremendous changes and developments due to rapid Restructuring, Deregulation and Open-access policies. Greater liberalization, larger market and increasing dependency on the electricity lead to the system operators to work on limited spinning reserve and to operate on vicinities to maximize the economy compromising on the reliability and security of the system for greater profits, which lead to establishment of a monitoring authority and accurate electronic system to prevent any untoward incidents like Blackouts. In any power system, unexpected outages of lines or transformers occur due to faults or other disturbances. These events may cause significant overloading of transmission lines or transformers, which in turn may lead to a viability crisis of the power system. The main role of power system control is to maintain a secure system state, i.e., to prevent the power system, moving from secure state into emergency state over the widest range of operating conditions. Security Constrained Optimal Power Flow (SCOPF is major tool used to improve the security of the system. In this work, Genetic algorithm has been used to solve the OPF and SCOPF problems. As initial effort conventional GA (binary coded based OPF and SCOPF is going to be attempted. The difficulties of binary coded GA in handling continuous search space lead to the evolution of real coded GA‟s. Solutions obtained using both the algorithms are compared. Case studies are made on the IEEE30 bus test system to demonstrate the ability of real coded GA in solving the OPF and SCOPF problems.
Institute of Scientific and Technical Information of China (English)
周红霞; 张安妮; 周方勇
2013-01-01
利用灰色聚类算法从地理条件、旅游资源和区域位置3个方面对济南西部湿地发展生态旅游进行了综合评价。结果表明，济南西部湿地在水体质量、文化古迹、交通条件等5个指标上评价为优类；在自然生态、土地开发、城镇分布等10个指标上评价为良类；在基础设施指标上评价为中类。说明其区域位置优于旅游资源，旅游资源优于地理条件，该结果可为济西湿地未来创造品牌，实现生态保护与经济发展的互动，建立可持续性的发展模式提供了依据。% Using the gray clustering algorithm, Jinan western wetland developing eco-tourism from the geographical conditions, tourism resources and regional location was conducted on a comprehensive evaluation. The results showed that the quality of water body, the cultural monuments, traffic conditions were evaluated as gifted class; assessment was good in the ten indicators including the natural ecology, land development and urban distribution class; class in this indicator evaluation infrastructure. The results indicated that the regional position was superior to tourism resources, the tourism resources was better than the geographical condi-tions. The results could provide basis to create the Jixi wetlands brand value in the future, ec-ological protection and economic development, and to create a sustainable to real live the in-structive of development model.
Palmer, Grant; Venkatapathy, Ethiraj
1993-01-01
Three solution algorithms, explicit underrelaxation, point implicit, and lower upper symmetric Gauss-Seidel (LUSGS), are used to compute nonequilibrium flow around the Apollo 4 return capsule at 62 km altitude. By varying the Mach number, the efficiency and robustness of the solution algorithms were tested for different levels of chemical stiffness. The performance of the solution algorithms degraded as the Mach number and stiffness of the flow increased. At Mach 15, 23, and 30, the LUSGS method produces an eight order of magnitude drop in the L2 norm of the energy residual in 1/3 to 1/2 the Cray C-90 computer time as compared to the point implicit and explicit under-relaxation methods. The explicit under-relaxation algorithm experienced convergence difficulties at Mach 23 and above. At Mach 40 the performance of the LUSGS algorithm deteriorates to the point it is out-performed by the point implicit method. The effects of the viscous terms are investigated. Grid dependency questions are explored.
Domínguez, Luis F.
2012-06-25
An algorithm for the solution of convex multiparametric mixed-integer nonlinear programming problems arising in process engineering problems under uncertainty is introduced. The proposed algorithm iterates between a multiparametric nonlinear programming subproblem and a mixed-integer nonlinear programming subproblem to provide a series of parametric upper and lower bounds. The primal subproblem is formulated by fixing the integer variables and solved through a series of multiparametric quadratic programming (mp-QP) problems based on quadratic approximations of the objective function, while the deterministic master subproblem is formulated so as to provide feasible integer solutions for the next primal subproblem. To reduce the computational effort when infeasibilities are encountered at the vertices of the critical regions (CRs) generated by the primal subproblem, a simplicial approximation approach is used to obtain CRs that are feasible at each of their vertices. The algorithm terminates when there does not exist an integer solution that is better than the one previously used by the primal problem. Through a series of examples, the proposed algorithm is compared with a multiparametric mixed-integer outer approximation (mp-MIOA) algorithm to demonstrate its computational advantages. © 2012 American Institute of Chemical Engineers (AIChE).
Detailed Modeling, Design, and Evaluation of a Scalable Multi-level Checkpointing System
Energy Technology Data Exchange (ETDEWEB)
Moody, A T; Bronevetsky, G; Mohror, K M; de Supinski, B R
2010-04-09
High-performance computing (HPC) systems are growing more powerful by utilizing more hardware components. As the system mean-time-before-failure correspondingly drops, applications must checkpoint more frequently to make progress. However, as the system memory sizes grow faster than the bandwidth to the parallel file system, the cost of checkpointing begins to dominate application run times. A potential solution to this problem is to use multi-level checkpointing, which employs multiple types of checkpoints with different costs and different levels of resiliency in a single run. The goal is to design light-weight checkpoints to handle the most common failure modes and rely on more expensive checkpoints for less common, but more severe failures. While this approach is theoretically promising, it has not been fully evaluated in a large-scale, production system context. To this end we have designed a system, called the Scalable Checkpoint/Restart (SCR) library, that writes checkpoints to storage on the compute nodes utilizing RAM, Flash, or disk, in addition to the parallel file system. We present the performance and reliability properties of SCR as well as a probabilistic Markov model that predicts its performance on current and future systems. We show that multi-level checkpointing improves efficiency on existing large-scale systems and that this benefit increases as the system size grows. In particular, we developed low-cost checkpoint schemes that are 100x-1000x faster than the parallel file system and effective against 85% of our system failures. This leads to a gain in machine efficiency of up to 35%, and it reduces the the load on the parallel file system by a factor of two on current and future systems.
B-Spline with Symplectic Algorithm Method for Solution of Time-Dependent Schr(o)dinger Equations
Institute of Scientific and Technical Information of China (English)
BIAN Xue-Bin; QIAO Hao-Xue; SHI Ting-Yun
2006-01-01
@@ A B-spline with the symplectic algorithm method for the solution of time-dependent Schr(o)dinger equations(TDSEs) is introduced. The spatial part of the wavefunction is expanded by B-spline and the time evolution is given in a symplectic scheme.
Directory of Open Access Journals (Sweden)
Tarek Bouktir
2012-06-01
Full Text Available This paper presents solution of optimal power flow (OPF problem of a power system via Differential Evolution (DE algorithm. The purpose of an electric power system is to deliver real power to the greatest number of users at the lowest possible cost all the time. So the objective is to minimize the total fuel cost of the generating units and also maintaining an acceptable system performance in terms of limits on generator reactive power outputs, bus voltages, Static VAR Compensator (SVC parameters and overload in transmission lines. CPU times can be reduced by decomposing the problem in two subproblems, the first subproblem minimize the fuel cost of generation and the second subproblem is a reactive power dispatch so optimum bus voltages can be determined and reduce the losses by controlling tap changes of the transformers and the static Var Compensators (SVC. To verify the proposed approach and for comparison purposes, we perform simulations on the Algerian network with 114 buses, 175 branches (lines and transformers and 15 generators. The obtained results indicate that DE is an easy to use, fast, robust and powerful optimization technique compared to the other global optimization methods such as PSO and GA.
Directory of Open Access Journals (Sweden)
Ari Muzakir
2017-05-01
Full Text Available Ease of deployment of digital image through the internet has positive and negative sides, especially for owners of the original digital image. The positive side of the ease of rapid deployment is the owner of that image deploys digital image files to various sites in the world address. While the downside is that if there is no copyright that serves as protector of the image it will be very easily recognized ownership by other parties. Watermarking is one solution to protect the copyright and know the results of the digital image. With Digital Image Watermarking, copyright resulting digital image will be protected through the insertion of additional information such as owner information and the authenticity of the digital image. The least significant bit (LSB is one of the algorithm is simple and easy to understand. The results of the simulations carried out using android smartphone shows that the LSB watermarking technique is not able to be seen by naked human eye, meaning there is no significant difference in the image of the original files with images that have been inserted watermarking. The resulting image has dimensions of 640x480 with a bit depth of 32 bits. In addition, to determine the function of the ability of the device (smartphone in processing the image using this application used black box testing.
Liu, Jianzhou; Zhang, Juan
2011-08-01
In this article, applying the properties of M-matrix and non-negative matrix, utilising eigenvalue inequalities of matrix's sum and product, we firstly develop new upper and lower matrix bounds of the solution for discrete coupled algebraic Riccati equation (DCARE). Secondly, we discuss the solution existence uniqueness condition of the DCARE using the developed upper and lower matrix bounds and a fixed point theorem. Thirdly, a new fixed iterative algorithm of the solution for the DCARE is shown. Finally, the corresponding numerical examples are given to illustrate the effectiveness of the developed results.
Directory of Open Access Journals (Sweden)
McDermott Drew
2009-08-01
Full Text Available Abstract Background Proteins interact through specific binding interfaces that contain many residues in domains. Protein interactions thus occur on three different levels of a concept hierarchy: whole-proteins, domains, and residues. Each level offers a distinct and complementary set of features for computationally predicting interactions, including functional genomic features of whole proteins, evolutionary features of domain families and physical-chemical features of individual residues. The predictions at each level could benefit from using the features at all three levels. However, it is not trivial as the features are provided at different granularity. Results To link up the predictions at the three levels, we propose a multi-level machine-learning framework that allows for explicit information flow between the levels. We demonstrate, using representative yeast interaction networks, that our algorithm is able to utilize complementary feature sets to make more accurate predictions at the three levels than when the three problems are approached independently. To facilitate application of our multi-level learning framework, we discuss three key aspects of multi-level learning and the corresponding design choices that we have made in the implementation of a concrete learning algorithm. 1 Architecture of information flow: we show the greater flexibility of bidirectional flow over independent levels and unidirectional flow; 2 Coupling mechanism of the different levels: We show how this can be accomplished via augmenting the training sets at each level, and discuss the prevention of error propagation between different levels by means of soft coupling; 3 Sparseness of data: We show that the multi-level framework compounds data sparsity issues, and discuss how this can be dealt with by building local models in information-rich parts of the data. Our proof-of-concept learning algorithm demonstrates the advantage of combining levels, and opens up
Survey of Collaboration Technologies in Multi-level Security Environments
2014-04-28
Dickson. 1996. "Teams in Organizations: Recent Research on Performance and Effectiveness". Annual Review of Psychology , 47:307-338. [32] Hall, D.L... Psychology , 94, 2, 535-546. [48] Moore, J.A. (2002). JView: an information visualization paradigm. Proc. SPIE, Vol. 4716, 367-374. In Enabling...date. Multilevel security solutions like the Multi-Layer Access Solution were developed by Gestalt and MAXIM Systems before these companies became
Vendor managed inventory in multi level supply chain
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Hamid Bani-Asadi
2017-01-01
Full Text Available Vendor managed inventory (VMI is one of the most effective methods for reducing bullwhip effect. This paper presents a mathematical VMI model where there are three levels of central storage, multi distribution centers and various retailors. The problem is formulated as a mixed integer programming by considering uncertainty on different input parameters. To cope with uncertainty, the study uses rectangular fuzzy numbers. We also propose two metaheuristics; namely, genetic algorithm and particle swarm optimization to solve the resulted problems for some large instances. The preliminary results have indicated that genetic algorithm could solve the proposed model faster than particle swarm optimization in terms of CPU time reaching to slightly better objective functions.
Multi-level fuzzy comprehensive appraisal on social effects of projects
Institute of Scientific and Technical Information of China (English)
孙立新; 李良宝; 李晓东; 王强
2004-01-01
The application of multi-level fuzzy comprehensive appraisal on social effects of projects has been studied. The principles for setting up an index system have been analyzed and the index system has been set up according to projects of construction. Models for multi-level fuzzy comprehensive appraisal have been offered and relative calculation steps have been given according to project instances.
Multi-level Governance in Environmental Risk Management
Directory of Open Access Journals (Sweden)
Petra Hiller
2013-04-01
Full Text Available The article examines regulatory strategies in the field of ecological disaster management with reference to the sociology of risk. The risk perspective draws attention to the fact that political strategies of regulation are to be understood as processes of risk transformation. The behavior of regulatory agencies is related to their perception of risks and opportunities. From this point of view, efforts in the field of disaster management appear as processes that turn perceived environmental threats into risks and opportunities for the agencies involved. The article shows the course of such a governance process which transforms environmental disasters into organizational risks and opportunities. This leads to the following research question: Which types of organizations favor strategies of risk avoidance and which organizations rather allow active pursuit of opportunities? The empirical part of this study is based on data obtained by field research in a multi-level negotiation system set up for managing hazardous wastes. Empirical findings support the assumption that organizational stability is a central condition for active pursuit of opportunities whereas organizational instability supports an orientation towards the avoidance of organizational risk. El artículo examina las estrategias reguladoras en el ámbito de la gestión de los desastres ecológicos, haciendo referencia a la sociología del riesgo. La perspectiva de riesgo pone su atención sobre el hecho de que las estrategias políticas de regulación se deben entender como procesos de transformación de riesgos. El comportamiento de las agencias reguladoras se relaciona con su percepción de los riesgos y oportunidades. Desde este punto de vista, los esfuerzos en el campo de la gestión de catástrofes se convierten en procesos que transforman las amenazas medioambientales (percibidas en riesgos y oportunidades para las agencias involucradas. El artículo muestra el desarrollo de este
Drift-Implicit Multi-Level Monte Carlo Tau-Leap Methods for Stochastic Reaction Networks
Ben Hammouda, Chiheb
2015-05-12
In biochemical systems, stochastic e↵ects can be caused by the presence of small numbers of certain reactant molecules. In this setting, discrete state-space and stochastic simulation approaches were proved to be more relevant than continuous state-space and deterministic ones. These stochastic models constitute the theory of stochastic reaction networks (SRNs). Furthermore, in some cases, the dynamics of fast and slow time scales can be well separated and this is characterized by what is called sti↵ness. For such problems, the existing discrete space-state stochastic path simulation methods, such as the stochastic simulation algorithm (SSA) and the explicit tau-leap method, can be very slow. Therefore, implicit tau-leap approxima- tions were developed to improve the numerical stability and provide more e cient simulation algorithms for these systems. One of the interesting tasks for SRNs is to approximate the expected values of some observables of the process at a certain fixed time T. This is can be achieved using Monte Carlo (MC) techniques. However, in a recent work, Anderson and Higham in 2013, proposed a more computationally e cient method which combines multi-level Monte Carlo (MLMC) technique with explicit tau-leap schemes. In this MSc thesis, we propose new fast stochastic algorithm, particularly designed 5 to address sti↵ systems, for approximating the expected values of some observables of SRNs. In fact, we take advantage of the idea of MLMC techniques and drift-implicit tau-leap approximation to construct a drift-implicit MLMC tau-leap estimator. In addition to accurately estimating the expected values of a given observable of SRNs at a final time T , our proposed estimator ensures the numerical stability with a lower cost than the MLMC explicit tau-leap algorithm, for systems including simultane- ously fast and slow species. The key contribution of our work is the coupling of two drift-implicit tau-leap paths, which is the basic brick for
Massive fungal biodiversity data re-annotation with multi-level clustering.
Vu, Duong; Szöke, Szániszló; Wiwie, Christian; Baumbach, Jan; Cardinali, Gianluigi; Röttger, Richard; Robert, Vincent
2014-10-30
With the availability of newer and cheaper sequencing methods, genomic data are being generated at an increasingly fast pace. In spite of the high degree of complexity of currently available search routines, the massive number of sequences available virtually prohibits quick and correct identification of large groups of sequences sharing common traits. Hence, there is a need for clustering tools for automatic knowledge extraction enabling the curation of large-scale databases. Current sophisticated approaches on sequence clustering are based on pairwise similarity matrices. This is impractical for databases of hundreds of thousands of sequences as such a similarity matrix alone would exceed the available memory. In this paper, a new approach called MultiLevel Clustering (MLC) is proposed which avoids a majority of sequence comparisons, and therefore, significantly reduces the total runtime for clustering. An implementation of the algorithm allowed clustering of all 344,239 ITS (Internal Transcribed Spacer) fungal sequences from GenBank utilizing only a normal desktop computer within 22 CPU-hours whereas the greedy clustering method took up to 242 CPU-hours.
Multidimensional Scaling and Genetic Algorithms : A Solution Approach to Avoid Local Minima
Etschberger, Stefan; Hilbert, Andreas
2002-01-01
Multidimensional scaling is very common in exploratory data analysis. It is mainly used to represent sets of objects with respect to their proximities in a low dimensional Euclidean space. Widely used optimization algorithms try to improve the representation via shifting its coordinates in direction of the negative gradient of a corresponding fit function. Depending on the initial configuration, the chosen algorithm and its parameter settings there is a possibility for the algorithm to termin...
Directory of Open Access Journals (Sweden)
Anan Mungwattana
2016-06-01
Full Text Available This paper deals with the vehicle routing problem with time windows (VRPTW. The VRPTW routes a set of vehicles to service customers having two-sided time windows, i.e. earliest and latest start of service times. The demand requests are served by capacitated vehicles with limited travel times to return to the depot. The purpose of this paper is to develop a hybrid algorithm that uses the modified push forward insertion heuristic (MPFIH, a λ-interchange local search descent method (λ-LSD and a genetic algorithm to solve the VRPTW with two objectives. The first objective aims to determine the minimum number of vehicles required and the second is to find the solution that minimizes the total travel time. A set of well-known benchmark problems are used to compare the quality of solutions. The results show that the proposed algorithm provides effective solutions compared with best found solutions and better than another heuristic used for comparison.
Bouallègue, Fayçal Ben; Crouzet, Jean-François; Comtat, Claude; Fourcade, Marjolaine; Mohammadi, Bijan; Mariano-Goulart, Denis
2007-07-01
This paper presents an extended 3-D exact rebinning formula in the Fourier space that leads to an iterative reprojection algorithm (iterative FOREPROJ), which enables the estimation of unmeasured oblique projection data on the basis of the whole set of measured data. In first approximation, this analytical formula also leads to an extended Fourier rebinning equation that is the basis for an approximate reprojection algorithm (extended FORE). These algorithms were evaluated on numerically simulated 3-D positron emission tomography (PET) data for the solution of the truncation problem, i.e., the estimation of the missing portions in the oblique projection data, before the application of algorithms that require complete projection data such as some rebinning methods (FOREX) or 3-D reconstruction algorithms (3DRP or direct Fourier methods). By taking advantage of all the 3-D data statistics, the iterative FOREPROJ reprojection provides a reliable alternative to the classical FOREPROJ method, which only exploits the low-statistics nonoblique data. It significantly improves the quality of the external reconstructed slices without loss of spatial resolution. As for the approximate extended FORE algorithm, it clearly exhibits limitations due to axial interpolations, but will require clinical studies with more realistic measured data in order to decide on its pertinence.
Hybrid algorithm: A cost efficient solution for ONU placement in Fiber-Wireless (FiWi) network
Bhatt, Uma Rathore; Chouhan, Nitin; Upadhyay, Raksha
2015-03-01
Fiber-Wireless (FiWi) network is a promising access technology as it integrates the technical merits of optical and wireless access networks. FiWi provides large bandwidth and high stability of optical network and lower cost of wireless network respectively. Therefore, FiWi gives users to access broadband services in an "anywhere-anytime" way. One of the key issues in FiWi network is its deployment cost, which depends on the number of ONUs in the network. Therefore optimal placement of ONUs is desirable to design a cost effective network. In this paper, we propose an algorithm for optimal placement of ONUs. First we place an ONU in the center of each grid then we form a set of wireless routers associated with each ONU according to wireless hop number. The number of ONUs are minimized in such a way, that all the wireless routers can communicate to at least one of the ONUs. The number of ONUs in the network further reduced by using genetic algorithm. The effectiveness of the proposed algorithm is tested by considering Internet traffic as well as peer-to-peer (p2p) traffic in the network, which is a current need. Simulation results show that the proposed algorithm is better than existing algorithms in minimizing number of ONUs in the network for both types of traffics. Hence proposed algorithm offers cost effective solution to design the FiWi network.
Hunziker, J.; Thorbecke, J.; Slob, E. C.
2014-12-01
Commonly, electromagnetic measurements for exploring and monitoring hydrocarbon reservoirs are inverted for the subsurface conductivity distribution by minimizing the difference between the actual data and a forward modeled dataset. The convergence of the inversion process to the correct solution strongly depends on the shape of the solution space. Since this is a non-linear problem, there exist a multitude of minima of which only the global one provides the correct conductivity values. To easily find the global minimum we desire it to have a broad cone of attraction, while it should also feature a very narrow bottom in order to obtain the subsurface conductivity with high resolution. In this study, we aim to determine which combination of input data corresponds to a favorable shape of the solution space. Since the solution space is N-dimensional, with N being the number of unknown subsurface parameters, plotting it is out of the question. In our approach, we use a genetic algorithm (Goldberg, 1989) to probe the solution space. Such algorithms have the advantage that every run of the same problem will end up at a different solution. Most of these solutions are expected to lie close to the global minimum. A situation where only few runs end up in the global minimum indicates that the solution space consists of a lot of local minima or that the cone of attraction of the global minimum is small. If a lot of runs end up with a similar data-misfit but with a large spread of the subsurface medium parameters in one or more direction, it can be concluded that the chosen data-input is not sensitive with respect to that direction. Compared to the study of Hunziker et al. 2014, we allow also to invert for subsurface boundaries and include more combinations of input datasets. The results so far suggest that it is essential to include the magnetic field in the inversion process in order to find the anisotropic conductivity values. ReferencesGoldberg, D. E., 1989. Genetic
Quantum algorithms for biomolecular solutions of the satisfiability problem on a quantum machine.
Chang, Weng-Long; Ren, Ting-Ting; Luo, Jun; Feng, Mang; Guo, Minyi; Weicheng Lin, Kawuu
2008-09-01
In this paper, we demonstrate that the logic computation performed by the DNA-based algorithm for solving general cases of the satisfiability problem can be implemented more efficiently by our proposed quantum algorithm on the quantum machine proposed by Deutsch. To test our theory, we carry out a three-quantum bit nuclear magnetic resonance experiment for solving the simplest satisfiability problem.
Orazbayev, B. B.; Orazbayeva, K. N.; Kurmangaziyeva, L. T.; Makhatova, V.E.
2015-01-01
Mathematical equations for the multi-criteria task of the optimisation of chemical engineering systems, for example for the optimisation of working regimes for industrial installations for benzene production, have been formulated and developed, and based on fuzzy mathematical methods, algorithms for their solution have been developed. Since the chemical engineering system, which is being researched, is characterised by multiple criteria and often functions in conditions of uncertainty, the presenting problem is formulated in the form of multi-criteria equations for fuzzy mathematical programming. New mathematical formulations for the problems being solved in a fuzzy environment and heuristic algorithms for their solution have been developed by the modification of various optimisation principles based on fuzzy mathematical methods.
Orazbayev, B B; Orazbayeva, K N; Kurmangaziyeva, L T; Makhatova, V E
2015-01-01
Mathematical equations for the multi-criteria task of the optimisation of chemical engineering systems, for example for the optimisation of working regimes for industrial installations for benzene production, have been formulated and developed, and based on fuzzy mathematical methods, algorithms for their solution have been developed. Since the chemical engineering system, which is being researched, is characterised by multiple criteria and often functions in conditions of uncertainty, the presenting problem is formulated in the form of multi-criteria equations for fuzzy mathematical programming. New mathematical formulations for the problems being solved in a fuzzy environment and heuristic algorithms for their solution have been developed by the modification of various optimisation principles based on fuzzy mathematical methods.
Institute of Scientific and Technical Information of China (English)
Bian Xue-Bin; Qiao Hao-Xue; Shi Ting-Yun
2007-01-01
A pseudospectral method with symplectic algorithm for the solution of time-dependent Schr(o)dinger equations(TDSE) is introduced. The spatial part of the wavefunction is discretized into sparse grid by pseudospectral method and the time evolution is given in symplectic scheme. This method allows us to obtain a highly accurate and stable solution of TDSE. The effectiveness and efficiency of this method is demonstrated by the high-order harmonic spectra of one-dimensional atom in strong laser field as compared with previously published work. The influence of the additional static electric field is also investigated.
Selçuk K. İşleyen; Ö. Faruk Baykoç
2008-01-01
We define a special case for the vehicle routing problem with stochastic demands (SC-VRPSD) where customer demands are normally distributed. We propose a new linear model for computing the expected length of a tour in SC-VRPSD. The proposed model is based on the integration of the “Traveling Salesman Problem” (TSP) and the Assignment Problem. For large-scale problems, we also use an Iterated Local Search (ILS) algorithm in order to reach an effective solution.
K—Dimensional Optimal Parallel Algorithm for the Solution of a General Class of Recurrence Equations
Institute of Scientific and Technical Information of China (English)
高庆狮; 刘志勇
1995-01-01
This paper proposes a parallel algorithm,called KDOP (K-Dimensional Optimal Parallel algorithm),to solve a general class of recurrence equations efficiently.The KDOP algorithm partitions the computation into a series of subcomputations,each of which is executed in the fashion that all the processors work simultaneously with each one executing an optimal sequential algorithm to solve a subcomputation task.The algorithm solves the equations in O(N/P) steps in EREW PRAM model (Exclusive Read Exclusive Write Parallel Random Access Machine model) using p≤N1-∈ processors,where N is the size of the problem,and ∈ is a given constant.This is an optimal algorithm (its sepeedup is O(p)) in the case of p≤N1-∈.Such an optimal speedup for this problem was previously achieved only in the case of p≤N0.5.The algorithm can be implemented on machines with multiple processing elements or pipelined vector machines with parallel memory systems.
Multi-level trellis coded modulation and multi-stage decoding
Costello, Daniel J., Jr.; Wu, Jiantian; Lin, Shu
1990-01-01
Several constructions for multi-level trellis codes are presented and many codes with better performance than previously known codes are found. These codes provide a flexible trade-off between coding gain, decoding complexity, and decoding delay. New multi-level trellis coded modulation schemes using generalized set partitioning methods are developed for Quadrature Amplitude Modulation (QAM) and Phase Shift Keying (PSK) signal sets. New rotationally invariant multi-level trellis codes which can be combined with differential encoding to resolve phase ambiguity are presented.
Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha
2014-10-01
In a companion manuscript (Frolov et al 2014 New J. Phys. 16 art. no.) , we developed a novel optimization method for the placement, sizing, and operation of flexible alternating current transmission system (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide series compensation (SC) via modification of line inductance. In this sequel manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (˜2700 nodes and ˜3300 lines). The results from the 30-bus network are used to study the general properties of the solutions, including nonlocality and sparsity. The Polish grid is used to demonstrate the computational efficiency of the heuristics that leverage sequential linearization of power flow constraints, and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, we can use the algorithm to solve a Polish transmission grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (i) uniform load growth, (ii) multiple overloaded configurations, and (iii) sequential generator retirements.
Energy Technology Data Exchange (ETDEWEB)
Frolov, Vladimir [Moscow Inst. of Physics and Technology (MIPT), Moscow (Russian Federation); Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chertkov, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2014-01-14
In a companion manuscript, we developed a novel optimization method for placement, sizing, and operation of Flexible Alternating Current Transmission System (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide Series Compensation (SC) via modification of line inductance. In this manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (~2700 nodes and ~3300 lines). The results on the 30-bus network are used to study the general properties of the solutions including non-locality and sparsity. The Polish grid is used as a demonstration of the computational efficiency of the heuristics that leverages sequential linearization of power flow constraints and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, the algorithm is able to solve an instance of Polish grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (a) uniform load growth, (b) multiple overloaded configurations, and (c) sequential generator retirements
Munhoven, G.
2013-03-01
The total alkalinity-pH equation, which relates total alkalinity and pH for a given set of total concentrations of the acid-base systems that contribute to total alkalinity in a given water sample, is reviewed and its mathematical properties established. We prove that the equation function is strictly monotone and always has exactly one positive root. Different commonly used approximations are discussed and compared. An original method to derive appropriate initial values for the iterative solution of the cubic polynomial equation based upon carbonate-borate-alkalinity is presented. We then review different methods that have been used to solve the total alkalinity-pH equation, with a main focus on biogeochemical models. The shortcomings and limitations of these methods are made out and discussed. We then present two variants of a new, robust and universally convergent algorithm to solve the total alkalinity-pH equation. This algorithm does not require any a priori knowledge of the solution. The iterative procedure is shown to converge from any starting value to the physical solution. The extra computational cost for the convergence security is only 10-15% compared to the fastest algorithm in our test series.
Institute of Scientific and Technical Information of China (English)
李春景; 顾传青
2003-01-01
Two efficient recursive algorithms epsilon- algorithm and eta-algorithm are approximants were used to accelerate the convergence of the power series with functionvalued coefficients and to estimate characteristic value of the integral equations. Famous two algorithms.
Optimized Graph Search Using Multi-Level Graph Clustering
Kala, Rahul; Shukla, Anupam; Tiwari, Ritu
Graphs find a variety of use in numerous domains especially because of their capability to model common problems. The social networking graphs that are used for social networking analysis, a feature given by various social networking sites are an example of this. Graphs can also be visualized in the search engines to carry search operations and provide results. Various searching algorithms have been developed for searching in graphs. In this paper we propose that the entire network graph be clustered. The larger graphs are clustered to make smaller graphs. These smaller graphs can again be clustered to further reduce the size of graph. The search is performed on the smallest graph to identify the general path, which may be further build up to actual nodes by working on the individual clusters involved. Since many searches are carried out on the same graph, clustering may be done once and the data may be used for multiple searches over the time. If the graph changes considerably, only then we may re-cluster the graph.
Solution for integer linear bilevel programming problems using orthogonal genetic algorithm
Institute of Scientific and Technical Information of China (English)
Hong Li; Li Zhang; Yongchang Jiao
2014-01-01
An integer linear bilevel programming problem is firstly transformed into a binary linear bilevel programming problem, and then converted into a single-level binary implicit program-ming. An orthogonal genetic algorithm is developed for solving the binary linear implicit programming problem based on the ortho-gonal design. The orthogonal design with the factor analysis, an experimental design method is applied to the genetic algorithm to make the algorithm more robust, statistical y sound and quickly convergent. A crossover operator formed by the orthogonal array and the factor analysis is presented. First, this crossover operator can generate a smal but representative sample of points as off-spring. After al of the better genes of these offspring are selected, a best combination among these offspring is then generated. The simulation results show the effectiveness of the proposed algo-rithm.
Cutting path as a Rural Postman Problem: solutions by Memetic Algorithms
Directory of Open Access Journals (Sweden)
Ana Maria Rodrigues
2012-01-01
Full Text Available The Rural Postman Problem (RPP is a particular Arc Routing Problem (ARP which consists of determining a minimum cost circuit on a graph so that a given subset of required edges is traversed. The RPP is an NP-hard problem with significant real-life applications. This paper introduces an original approach based on Memetic Algorithms - the MARP algorithm - to solve the RPP and, also deals with an interesting Industrial Application, which focuses on the path optimization for component cutting operations. Memetic Algorithms are a class of Metaheuristics which may be seen as a population strategy that involves cooperation and competition processes between population elements and integrates “social knowledge”, using a local search procedure. The MARP algorithm is tested with different groups of instances and the results are compared with those gathered from other publications. MARP is also used in the context of various real-life applications.
Deb, Kalyanmoy; Mohan, Manikanth; Mishra, Shikhar
2005-01-01
Since the suggestion of a computing procedure of multiple Pareto-optimal solutions in multi-objective optimization problems in the early Nineties, researchers have been on the look out for a procedure which is computationally fast and simultaneously capable of finding a well-converged and well-distributed set of solutions. Most multi-objective evolutionary algorithms (MOEAs) developed in the past decade are either good for achieving a well-distributed solutions at the expense of a large computational effort or computationally fast at the expense of achieving a not-so-good distribution of solutions. For example, although the Strength Pareto Evolutionary Algorithm or SPEA (Zitzler and Thiele, 1999) produces a much better distribution compared to the elitist non-dominated sorting GA or NSGA-II (Deb et al., 2002a), the computational time needed to run SPEA is much greater. In this paper, we evaluate a recently-proposed steady-state MOEA (Deb et al., 2003) which was developed based on the epsilon-dominance concept introduced earlier(Laumanns et al., 2002) and using efficient parent and archive update strategies for achieving a well-distributed and well-converged set of solutions quickly. Based on an extensive comparative study with four other state-of-the-art MOEAs on a number of two, three, and four objective test problems, it is observed that the steady-state MOEA is a good compromise in terms of convergence near to the Pareto-optimal front, diversity of solutions, and computational time. Moreover, the epsilon-MOEA is a step closer towards making MOEAs pragmatic, particularly allowing a decision-maker to control the achievable accuracy in the obtained Pareto-optimal solutions.
Integration of multi-level marketing management systems geographically industry development
Directory of Open Access Journals (Sweden)
Aleksandr Lavrov
2015-05-01
Full Text Available In the article the authors attempt to develop a multi-level management system territorially industry development in market conditions, built in the widespread use of various types of marketing and their horizontal and vertical integration.
GROUND WATER MONITORING AND SAMPLING: MULTI-LEVEL VERSUS TRADITIONAL METHODS – WHAT’S WHAT?
Recent studies have been conducted to evaluate different sampling techniques for determining VOC concentrations in groundwater. Samples were obtained using multi-level and traditional sampling techniques in three monitoring wells at the Raymark Superfund site in Stratford, CT. Ve...
Proactive Decision Support Via Narrative-Integrated Multi-Level Support System (NIMSS)
2014-11-30
30/2014 Final Report 07/11/2014 - 11/30/2014 Final Report - Proactive Decision Support Via Narrative -Integrated Multi-Level Support System (NIMSS...think, demonstrated via a realistic Naval/Marine Corps warfighting domain. Context-driven decision making; proactive decision support; narrative ...0005, CDRL B001 Proactive Decision Support via Narrative -Integrated Multi-level Support System (NIMSS) CHI Project # 14002 Purchase Order: N00014
PELAKSANAAN JUAL BELI MELALUI SISTEM MULTI LEVEL MARKETING PERSPEKTIF HUKUM ISLAM
Ayu Dewi Utami; Nurul Maghfiroh; Bambang Tjatur Iswanto
2016-01-01
Bisnis Multi Level Marketing (MLM) cukup berperan dalam menggerakkan roda perekonomian masyarakat. Dalam sejumlah kasus, Multi Level Marketing (MLM) kerap dijadikan kedok dari bisnis money game dan mendewakan passive income. Bertolak dari kasus kasus seperti itulah, Majelis Ulama Indonesia (MUI) telah menggodok prinsip-prinsip bisnis ini secara syariah termasuk marketing plannya. Tujuannya untuk melindungi pengusaha dan mitra bisnisnya (masyarakat) dari praktik bisnis yang haram atau syubhat....
Rapid Solution of Finite Element Equations on Locally Refined Grids by Multi-Level Methods.
1980-05-01
oscillatory eigenfunctions. For practical purposes many possible smoothing iterations would be acceptable. Jacobi, Gauss -Seidel, and symmetric SOR are...considerable work with rectangular tensor product elements on locally refined grids, Cannon (1980). 55 Figure 10. Support of a Basis Function Figure 11...uses a symmetric Gauss -Seidel -4 - im 66 smoothing iteration rather than the simultaneous displacement iteration used here. While comparisons for quasi
Multi-Level Wavelet Shannon Entropy-Based Method for Single-Sensor Fault Location
Directory of Open Access Journals (Sweden)
Qiaoning Yang
2015-10-01
Full Text Available In actual application, sensors are prone to failure because of harsh environments, battery drain, and sensor aging. Sensor fault location is an important step for follow-up sensor fault detection. In this paper, two new multi-level wavelet Shannon entropies (multi-level wavelet time Shannon entropy and multi-level wavelet time-energy Shannon entropy are defined. They take full advantage of sensor fault frequency distribution and energy distribution across multi-subband in wavelet domain. Based on the multi-level wavelet Shannon entropy, a method is proposed for single sensor fault location. The method firstly uses a criterion of maximum energy-to-Shannon entropy ratio to select the appropriate wavelet base for signal analysis. Then multi-level wavelet time Shannon entropy and multi-level wavelet time-energy Shannon entropy are used to locate the fault. The method is validated using practical chemical gas concentration data from a gas sensor array. Compared with wavelet time Shannon entropy and wavelet energy Shannon entropy, the experimental results demonstrate that the proposed method can achieve accurate location of a single sensor fault and has good anti-noise ability. The proposed method is feasible and effective for single-sensor fault location.
求解FJSP的混合遗传一蚁群算法%Hybrid genetic algorithm-ant colony optimization for FJSP solution
Institute of Scientific and Technical Information of China (English)
董蓉; 何卫平
2012-01-01
为更有效地求解柔性作业车间调度问题，综合考虑其中的机器分配与工序排序问题，建立了相关析取图模型，提出一种混合遗传一蚁群算法。该算法首先通过遗传算法获取问题的较优解，据此给出蚁群算法的信息素初始分布；之后充分利用蚁群算法的正反馈性进行求解，采用精英策略对蚁群的信息素进行局部更新；最后借鉴遗传算法交叉算子的邻域搜索特性扩大蚁群算法解的搜索空间，从而改善解的质量。通过3个经典算例的实验仿真，以及与其他算法的比较，验证了所提算法的可行性与有效性。%To solve Flexible Job-Shop Scheduling Problem(FJSP)more effectively, a related disjunctive graph model was built and a hybrid Genetic Algorithm(GA)-Ant Colony Optimization( ACO) was proposed by considering equip- ments arrangement and operation sequencing. In this algorithm, a better solution to the problem was obtained by ge- netic algorithm, and pheromones initial distribution of ACO was provided on this basis. The positive feedback of ACO was used to solve the problem, and the local update of the pheromones were conducted by elitist strategy. The neighborhood searching feature of crossover operator in GA was used to increase the search space of ACO, thus the quality of solution was improved. Through the experimental simulation of 3 classical examples, the feasibility and effectiveness of proposed algorithm were verified.
Librino, Federico; Zorzi, Michele
2012-01-01
A novel iterative algorithm for the efficient computation of the intersection areas of an arbitrary number of circles is presented. The algorithm, based on a trellis-structure, hinges on two geometric results which allow the existence-check and the computation of the area of the intersection regions generated by more than three circles by simple algebraic manipulations of the intersection areas of a smaller number of circles. The presented algorithm is a powerful tool for the performance analysis of wireless networks, and finds many applications, ranging from sensor to cellular networks. As an example of practical application, an insightful study of the uplink outage probability of in a wireless network with cooperative access points as a function of the transmission power and access point density is presented.
Current algorithmic solutions for peptide-based proteomics data generation and identification.
Hoopmann, Michael R; Moritz, Robert L
2013-02-01
Peptide-based proteomic data sets are ever increasing in size and complexity. These data sets provide computational challenges when attempting to quickly analyze spectra and obtain correct protein identifications. Database search and de novo algorithms must consider high-resolution MS/MS spectra and alternative fragmentation methods. Protein inference is a tricky problem when analyzing large data sets of degenerate peptide identifications. Combining multiple algorithms for improved peptide identification puts significant strain on computational systems when investigating large data sets. This review highlights some of the recent developments in peptide and protein identification algorithms for analyzing shotgun mass spectrometry data when encountering the aforementioned hurdles. Also explored are the roles that analytical pipelines, public spectral libraries, and cloud computing play in the evolution of peptide-based proteomics.
SOLUTION OF NONLINEAR PROBLEMS IN WATER RESOURCES SYSTEMS BY GENETIC ALGORITHM
Directory of Open Access Journals (Sweden)
Ahmet BAYLAR
1998-03-01
Full Text Available Genetic Algorithm methodology is a genetic process treated on computer which is considering evolution process in the nature. The genetic operations takes place within the chromosomes stored in computer memory. By means of various operators, the genetic knowledge in chromosomes change continuously and success of the community progressively increases as a result of these operations. The primary purpose of this study is calculation of nonlinear programming problems in water resources systems by Genetic Algorithm. For this purpose a Genetic Algoritm based optimization program were developed. It can be concluded that the results obtained from the genetic search based method give the precise results.
A Sequential Quadratic Programming Algorithm Using An Incomplete Solution of the Subproblem
1993-05-01
Research Stanford University tDept. de Estadistica y Econometria Universidad Carlos III de Madrid Abstract We analyze sequential quadratic programming...xEK- NP s.t. c(x) > 0, where F : R " --+ R and c : R1 --+ Rm. Since we shall not assume second derivatives are known, computing x*, a point satisfying...algorithm We first present an outline of the algorithm. Given Ho positive definite, z0 and A0, select P-1 0 O, 0 < a < r 1,/7 < > jc-(xo)lo,, _ Ž IIAoll
A sequential quadratic programming algorithm using an incomplete solution of the subproblem
Energy Technology Data Exchange (ETDEWEB)
Murray, W. [Stanford Univ., CA (United States). Systems Optimization Lab.; Prieto, F.J. [Universidad `Carlos III` de Madrid (Spain). Dept. de Estadistica y Econometria
1993-05-01
We analyze sequential quadratic programming (SQP) methods to solve nonlinear constrained optimization problems that are more flexible in their definition than standard SQP methods. The type of flexibility introduced is motivated by the necessity to deviate from the standard approach when solving large problems. Specifically we no longer require a minimizer of the QP subproblem to be determined or particular Lagrange multiplier estimates to be used. Our main focus is on an SQP algorithm that uses a particular augmented Lagrangian merit function. New results are derived for this algorithm under weaker conditions than previously assumed; in particular, it is not assumed that the iterates lie on a compact set.
El-Ajou, Ahmad; Arqub, Omar Abu; Momani, Shaher
2015-07-01
In this paper, explicit and approximate solutions of the nonlinear fractional KdV-Burgers equation with time-space-fractional derivatives are presented and discussed. The solutions of our equation are calculated in the form of rabidly convergent series with easily computable components. The utilized method is a numerical technique based on the generalized Taylor series formula which constructs an analytical solution in the form of a convergent series. Five illustrative applications are given to demonstrate the effectiveness and the leverage of the present method. Graphical results and series formulas are utilized and discussed quantitatively to illustrate the solution. The results reveal that the method is very effective and simple in determination of solution of the fractional KdV-Burgers equation.
GLOBAL OPTIMIZATION OF PUMP CONFIGURATION PROBLEM USING EXTENDED CROWDING GENETIC ALGORITHM
Institute of Scientific and Technical Information of China (English)
Zhang Guijun; Wu Tihua; Ye Rong
2004-01-01
An extended crowding genetic algorithm (ECGA) is introduced for solving optimal pump configuration problem,which was presented by T.Westerlund in 1994.This problem has been found to be non-convex,and the objective function contained several local optima and global optimality could not be ensured by all the traditional MINLP optimization method.The concepts of species conserving and composite encoding are introduced to crowding genetic algorithm (CGA) for maintain the diversity of population more effectively and coping with the continuous and/or discrete variables in MINLP problem.The solution of three-levels pump configuration got from DICOPT++ software (OA algorithm) is also given.By comparing with the solutions obtained from DICOPT++,ECP method,and MIN-MIN method,the ECGA algorithm proved to be very effective in finding the global optimal solution of multi-levels pump configuration via using the problem-specific information.
Eavesdropping in a quantum secret sharing protocol based on Grover algorithm and its solution
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
A detailed analysis has showed that the quantum secret sharing protocol based on the Grover algorithm (Phys Rev A, 2003, 68: 022306) is insecure. A dishonest receiver may obtain the full information without being detected. A quantum secret-sharing protocol is presents here, which mends the security loophole of the original secret-sharing protocol, and doubles the information capacity.
Solution to the problem of ant being stuck by ant colony routing algorithm
Institute of Scientific and Technical Information of China (English)
ZHAO Jing; TONG Wei-ming
2009-01-01
Many ant colony routing (ACR) algorithms have been presented in recent years, but few have studied the problem that ants will get stuck with probability in any terminal host when they are searching paths to route packets around a network. The problem has to be faced when designing and implementing the ACR algorithm. This article analyzes in detail the differences between the ACR and the ant colony optimization (ACO). Besides, particular restrictions on the ACR are pointed out and the three causes of ant being-stuck problem are obtained. Furthermore, this article proposes a new ant searching mechanism through dual path-checking and online routing loop removing by every intermediate node an ant visited and the destination host respectively, to solve the problem of ant being stuck and routing loop simultaneously. The result of numerical simulation is abstracted from one real network. Compared with existing two typical ACR algorithms, it shows that the proposed algorithm can settle the problem of ant being stuck and achieve more effective searching outcome for optimization path.
Institute of Scientific and Technical Information of China (English)
Gao Chao
2008-01-01
This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct (PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power components,overall system loss and magnetic component selection based upon the single-level boost PFC switch converter. Besides,relying on the application of mi-croprocessor in power converter technology and DSP (Digital Signal Processing) chip's strong cal-culating capacity,the letter presents the adoption of modified scheme of tri-level boost PFC converter under the control of predictive control algorithm. Moreover,the operating principle and control method are specified,the results of circuit test and analysis are provided and the advantages of pre-dictive control technology-based multi-level boost PFC converter is verified.
Institute of Scientific and Technical Information of China (English)
Xie Ping DING
2012-01-01
Some classes of mixed equilibrium problems and bilevel mixed equilibrium problems are introduced and studied in reflexive Banach spaces.First,by using a minimax inequality,some new existence results of solutious and the behavior of solution set for the mixed equilibrium problems and the bilevel mixed equilibrium problems are proved under suitable assumptions without the coercive conditions.Next,by using auxiliary principle technique,some new iterative algorithms for solving the mixed equilibrium problems and the bilevel mixed equilibrium problems are suggested and analyzed.The strong convergence of the iterative sequences generated by the proposed algorithms is proved under suitable assumptions without the coercive conditions.These results are new and generalize some recent results in this field.
DEFF Research Database (Denmark)
Ipsen, Christine; Poulsen, Signe; Gish, Liv
2014-01-01
be addressed and how prevention of work-related stress can be understood. In addition to supporting a new understanding of prevention, the use of the model also results in concrete changes which become solutions to the work-place’s current and specific problems. The use of the PoWRS model thus enables an SME...... development of organizational level changes. By employing the model the companies became capable of developing new work practices in a multi-level participatory process using local in-house resources as facilitators. The PoWRS model was developed as part of the research project:”Productivity and Well......-being”. The aim of the research project was to develop and test a multi-level participatory intervention model which could be applied by SMEs which are often characterized by their lack of resources such as not having access to HR-resources to facilitate change processes. The PoWRS model targets the work (primary...
Directory of Open Access Journals (Sweden)
2009-03-01
Full Text Available We define a special case for the vehicle routing problem with stochastic demands (SC-VRPSD where customer demands are normally distributed. We propose a new linear model for computing the expected length of a tour in SC-VRPSD. The proposed model is based on the integration of the “Traveling Salesman Problem” (TSP and the Assignment Problem. For large-scale problems, we also use an Iterated Local Search (ILS algorithm in order to reach an effective solution.
DEFF Research Database (Denmark)
Sousa, Tiago; Morais, Hugo; Castro, Rui
2016-01-01
. The proposed algorithms have been developed as modules to be more flexible their use by other metaheuristics than just simulated annealing. The simulated annealing with different initial solution algorithms has been tested in a 37-bus distribution network with distributed resources, especially electric...
Directory of Open Access Journals (Sweden)
Ambarish Panda
2016-09-01
Full Text Available A new evolutionary hybrid algorithm (HA has been proposed in this work for environmental optimal power flow (EOPF problem. The EOPF problem has been formulated in a nonlinear constrained multi objective optimization framework. Considering the intermittency of available wind power a cost model of the wind and thermal generation system is developed. Suitably formed objective function considering the operational cost, cost of emission, real power loss and cost of installation of FACTS devices for maintaining a stable voltage in the system has been optimized with HA and compared with particle swarm optimization algorithm (PSOA to prove its effectiveness. All the simulations are carried out in MATLAB/SIMULINK environment taking IEEE30 bus as the test system.
Problèmes de type obstacle : algorithmes de résolution
African Journals Online (AJOL)
discrétisation de l'inéquation variationnelle par la méthode des éléments finis linéaires conduit à l'étude de trois ... Mots clés : Problème de l'obstacle - Inéquation variationnelle - Eléments finis- Algorithmes ...... John Wiley and ... North-Holland.
Directory of Open Access Journals (Sweden)
Tushar Tyagi
2016-11-01
Full Text Available This paper presents solution of multi-objective optimal dispatch (MOOD problem of solar-wind-thermal system by improved stochastic fractal search (ISFSA algorithm. Stochastic fractal search (SFSA is inspired by the phenomenon of natural growth called fractal. It utilizes the concept of creating fractals for conducting a search through the problem domain with the help of two main operations diffusion and updating. To improve the exploration and exploitation capability of SFSA, scale factor is used in place of random operator. The SFSA and proposed ISFSA is implemented and tested on six different multi objective complex test systems of power system. TOPSIS is used here as a decision making tool to find the best compromise solution between the two conflicting objectives. The outcomes of simulation results are also compared with recent reported methods to confirm the superiority and validation of proposed approach.
Directory of Open Access Journals (Sweden)
Alvarado-Cárdenas R.
2012-07-01
Full Text Available In this research it is proposed a genetic algorithm with “natural crossover” that was applied to a continuous-discrete representation in order to optimize truss structures. The objective is to reduce the weight by restraining node displacement and limiting the cross sections to use. The solutions are combined applying two types of crossovers to the same representation, thus allowing to effectively explore the search space. The results are validated by comparing those found herein against those found in current literature for the case of the design of a 70 m span bridge truss structure. Solutions obtained are lighter and with different topology. Additionally, a case study is proposed, a greenhouse roof truss structure, in order to generate an actual application that is built in a practical scale and it is loaded afterwards to verify its strength.
A Hybrid Multi-Tenant Database Schema for Multi-Level Quality of Service
Directory of Open Access Journals (Sweden)
Ahmed I. Saleh
2014-11-01
Full Text Available Software as a Service (SaaS providers can serve hundreds of thousands of customers using sharable resources to reduce costs. Multi-tenancy architecture allows SaaS providers to run a single application and a database instance, which support multiple tenants with various business needs and priorities. Until now, the database management systems (DBMSs have not had the notion of multi-tenancy, and they have not been equipped to handle customization or scalability requirements, that are typical in multi-tenant applications. The multi-tenant database performance should adapt to tenants workloads and fit their special requirements. In this paper, we propose a new multi-tenant database schema design approach, that adapts to multi-tenant application requirements, in addition to tenants needs of data security, isolation, queries performance and response time speed. Our proposed methodology provides a trade-off between the performance and the storage space. This proposal caters for the diversity in tenants via defining multi-level quality of service for the different types of tenants, depending on tenant rate and system rate. The proposal presents a new technique to distribute data in a multi-tenant database horizontally to a set of allotment tables using an isolation point, and vertically to a set of extension tables using a merger point. Finally, we present a prototype implementation of our method using a real-world case study, showing that the proposed solution can achieve high scalability and increase performance for tenants who need speedy performance and economize storage space for tenants who do not have demanding quality of service.
Enabling the MLSpOC (Multi-Level Space Operations Center) of the Future
Missal, D.
2012-09-01
accredited today at multiple sites both CONUS and OCONUS. It is designed to assist information systems developers achieve DCID 6/3 Protection Level 4 or 5 (PL4 or PL5) or DoD SABI C&A for SECRET-to-UNCLASSIFIED systems (PL3). The product is on the DoD/DNI Unified Cross-domain Management Office's (UCDMO) Baseline of accredited solutions, and is the only solution on the Baseline which the Government considers to be an "All-in-One" approach to the Cross-domain Security challenge. Our solution is also the only PL-4 Cloud in existence and that is deployed and operational in the entire world today (at DIA). The Space marketplace is a very unique cross-domain challenge, as a need exists for Unclassified SSA Data Sharing at a deeper and more fundamental level than anywhere else in the IC or DoD. For instance, certain Agencies and/or Programs have a requirement to share information with Partner Nations that are not considered to be "friendly" (e.g. China). Our Solution is the ONLY solution in the world today that's achieved C&A, and that is uniquely positioned to enable the Multi-level Space Operations Center (MLSpOC) of the Future.
DEFF Research Database (Denmark)
Liu, Hui; Ma, Ke; Loh, Poh Chiang;
2016-01-01
The modular multi-level converter has become an interesting candidate in high-voltage DC systems due to its higher voltage levels and modular construction. Low-voltage ride-through is an important grid requirement for modular multi-level converter–high-voltage DC since not only causes control...... challenges but may also result in overstressed components for the modular multi-level converter. However, the thermal loading of the modular multi-level converter under various grid faults has not yet been clarified. In this article, the power loss and thermal performance of the modular multi-level converter...... during grid voltage dips are studied. The impacts of two typical grid faults to the modular multi-level converter in terms of operating and loading conditions are analytically researched and simulated. It has been found that the operating and loading conditions of the modular multi-level converter under...
An efficient dissipative particle dynamics-based algorithm for simulating electrolyte solutions
Medina, Stefan; Wang, Zhen-Gang; Schmid, Friederike
2014-01-01
We propose an efficient simulation algorithm based on the dissipative particle dynamics (DPD) method for studying electrohydrodynamic phenomena in electrolyte fluids. The fluid flow is mimicked with DPD particles while the evolution of the concentration of the ionic species is described using Brownian pseudo particles. The method is designed especially for systems with high salt concentrations, as explicit treatment of the salt ions becomes computationally expensive. For illustration, we apply the method to electro-osmotic flow over patterned, superhydrophobic surfaces. The results are in good agreement with recent theoretical predictions.
Ghazzai, Hakim
2012-01-01
The Base Station (BS) sleeping strategy has become a well-known technique to achieve energy savings in cellular networks by switching off redundant BSs mainly for lightly loaded networks. Besides, the exploitation of renewable energies, as additional power sources in smart grids, becomes a real challenge to network operators to reduce power costs. In this paper, we propose a method based on genetic algorithms that decreases the energy consumption of a Long-Term Evolution (LTE) cellular network by not only shutting down underutilized BSs but also by optimizing the amounts of energy procured from the smart grid without affecting the desired Quality of Service. © 2012 Springer-Verlag.
2012-03-01
Rao discusses the most common gradient search algorithms in [71] along with some heuristic ones that use some added randomness to direct the search... aircrews and mission planners who have interest in this type of problem. 98 Target T=Threat T x1 x2 B ou nd ar y B ou nd ar y T θ V (tf , x1(tf ), x2(tf...processing. The most valuable product to mission planners and aircrews is not the set of statistics describing expected values, variances, and covariances and
Algorithmic and technical improvements: Optimal solutions to the (Generalized) Multi-Weber Problem
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
1980-10-01
superior to projected SOR and modified block SOR (see TalbIs 5.3 and 6.3, and Section 4). 3. For high accuracy solutions of the discrete LCP, one should use...of variational inequalities. Math. Computation, 28(1974), pp. 963-971. R. GLOWINSKI. La methode de relaxation. Rendiconti di Matematica , 14 (1971
Displacement measurement with multi-level spiral phase filtering in speckle interferometry
Aguilar, Alberto; Dávila, Abundio; Landgrave, J. E. A.
2014-01-01
A multi-level spiral phase filter is proposed in electronic speckle pattern interferometry (ESPI) for out-of-plane displacement measurements. This filter generates a particular kind of speckle pattern that results from the convolution of standard speckles with the filter point spread function (Fourier transform). We shall refer to it as a vortex-filtered speckle pattern (VF-SP). It is shown here that if unresolved and fully developed VF-SPs are generated, then each speckle contains embedded phase terms which can be controlled by the multi-level spiral filter rotation. This mechanism effectively allows the application of standard phase extraction procedures for displacement measurements. Numerical simulations of an interferometer working with VF-SPs were done to verify this technique. Experimental validation was achieved with an out-of-plane electronic speckle pattern interferometer, in which an Liquid Crystal on Silicon (LCoS) was used to generate the multi-level spiral phase filters.
A Multi-Level Decision Fusion Strategy for Condition Based Maintenance of Composite Structures
Directory of Open Access Journals (Sweden)
Zahra Sharif Khodaei
2016-09-01
Full Text Available In this work, a multi-level decision fusion strategy is proposed which weighs the Value of Information (VoI against the intended functions of a Structural Health Monitoring (SHM system. This paper presents a multi-level approach for three different maintenance strategies in which the performance of the SHM systems is evaluated against its intended functions. Level 1 diagnosis results in damage existence with minimum sensors covering a large area by finding the maximum energy difference for the guided waves propagating in pristine structure and the post-impact state; Level 2 diagnosis provides damage detection and approximate localization using an approach based on Electro-Mechanical Impedance (EMI measures, while Level 3 characterizes damage (exact location and size in addition to its detection by utilising a Weighted Energy Arrival Method (WEAM. The proposed multi-level strategy is verified and validated experimentally by detection of Barely Visible Impact Damage (BVID on a curved composite fuselage panel.
NOVEL MULTI-LEVEL OPTIMIZATION METHOD FOR CHEMICAL COMPLEX USING INTELLIGENT AGENT
Institute of Scientific and Technical Information of China (English)
Xiaojun LI; Huanjun YU; Shangxu HU
2003-01-01
Multi-level optimization of complex chemical complex was comprehensively analyzed, including the optimization of management plan, production scheme, operating conditions, etc. The software framework of multi-level optimization of chemical complex was worked out. Basing upon the frame of multi-level optimization, the intelligent agent technique was adopted to search for global optimum. The organization, function, design and the implementation of a series of intelligent agents were discussed. According to the strategy that to spend most computing time in optimization solving and much less time in exchanging information regarding the tasks and results of optimization through network, the communication mechanism and cooperation rules for Multi-Agent System for hierarchically optimizing chemical complex was proposed.
Debbarma, Sanjoy; Saikia, Lalit Chandra; Sinha, Nidul
2014-03-01
Present work focused on automatic generation control (AGC) of a three unequal area thermal systems considering reheat turbines and appropriate generation rate constraints (GRC). A fractional order (FO) controller named as I(λ)D(µ) controller based on crone approximation is proposed for the first time as an appropriate technique to solve the multi-area AGC problem in power systems. A recently developed metaheuristic algorithm known as firefly algorithm (FA) is used for the simultaneous optimization of the gains and other parameters such as order of integrator (λ) and differentiator (μ) of I(λ)D(µ) controller and governor speed regulation parameters (R). The dynamic responses corresponding to optimized I(λ)D(µ) controller gains, λ, μ, and R are compared with that of classical integer order (IO) controllers such as I, PI and PID controllers. Simulation results show that the proposed I(λ)D(µ) controller provides more improved dynamic responses and outperforms the IO based classical controllers. Further, sensitivity analysis confirms the robustness of the so optimized I(λ)D(µ) controller to wide changes in system loading conditions and size and position of SLP. Proposed controller is also found to have performed well as compared to IO based controllers when SLP takes place simultaneously in any two areas or all the areas. Robustness of the proposed I(λ)D(µ) controller is also tested against system parameter variations.
Approximated Vector Diffraction Theory for Readout Signal of Multi-Level Run-Length-Limited Discs
Institute of Scientific and Technical Information of China (English)
SONG Jie; XIA Si-Fei; XU Duan-Yi
2008-01-01
Multi-level run-length-limited read-only optical storage is a kind of high density storage method. The width and height of recording marks are varied with different levels, which is the key technology for the optical storage. When the readout signal of these discs with complex recording marks is computed by vector analysis method, it is very hard and time-consuming. Approximated vector computation combines the convenience of scalar method and precision of vector method, which is effective for multi-level run-length-limited read-only optical storage.
Off-resonant transitions in the collective dynamics of multi-level atomic ensembles
DEFF Research Database (Denmark)
Miroshnychenko, Yevhen; Mølmer, Klaus
2013-01-01
We study the contributions of off-resonant transitions to the dynamics of a system of N multi-level atoms sharing one excitation and interacting with the quantized vector electromagnetic field. The rotating wave approximation significantly simplifies the derivation of the equations of motion...... the photon mode frequencies are extended to incorporate negative values. We explicitly derive the atom–atom interaction for multi-level atoms, coupled to the full vector electromagnetic field, and we recover also in this general case the validity of the results obtained by the extension to negative...
DEFF Research Database (Denmark)
Kofoed, Jens Peter
2007-01-01
This paper presents an expression describing the vertical distribution of overtopping, the experimental work leading to this, as well as the use of the expression for numerical optimization of the geometrical layout of the multi level overtopping based wave energy converter Seawave Slot-cone Gene......This paper presents an expression describing the vertical distribution of overtopping, the experimental work leading to this, as well as the use of the expression for numerical optimization of the geometrical layout of the multi level overtopping based wave energy converter Seawave Slot...
Axelsson, Robert; Angelstam, Per; Myhrman, Lennart; Sädbom, Stefan; Ivarsson, Milis; Elbakidze, Marine; Andersson, Kenneth; Cupa, Petr; Diry, Christian; Doyon, Frederic; Drotz, Marcus K; Hjorth, Arne; Hermansson, Jan Olof; Kullberg, Thomas; Lickers, F Henry; McTaggart, Johanna; Olsson, Anders; Pautov, Yurij; Svensson, Lennart; Törnblom, Johan
2013-03-01
To implement policies about sustainable landscapes and rural development necessitates social learning about states and trends of sustainability indicators, norms that define sustainability, and adaptive multi-level governance. We evaluate the extent to which social learning at multiple governance levels for sustainable landscapes occur in 18 local development initiatives in the network of Sustainable Bergslagen in Sweden. We mapped activities over time, and interviewed key actors in the network about social learning. While activities resulted in exchange of experiences and some local solutions, a major challenge was to secure systematic social learning and make new knowledge explicit at multiple levels. None of the development initiatives used a systematic approach to secure social learning, and sustainability assessments were not made systematically. We discuss how social learning can be improved, and how a learning network of development initiatives could be realized.
Cui, Ganglong; Yang, Weitao
2011-05-28
The significance of conical intersections in photophysics, photochemistry, and photodissociation of polyatomic molecules in gas phase has been demonstrated by numerous experimental and theoretical studies. Optimization of conical intersections of small- and medium-size molecules in gas phase has currently become a routine optimization process, as it has been implemented in many electronic structure packages. However, optimization of conical intersections of small- and medium-size molecules in solution or macromolecules remains inefficient, even poorly defined, due to large number of degrees of freedom and costly evaluations of gradient difference and nonadiabatic coupling vectors. In this work, based on the sequential quantum mechanics and molecular mechanics (QM/MM) and QM/MM-minimum free energy path methods, we have designed two conical intersection optimization methods for small- and medium-size molecules in solution or macromolecules. The first one is sequential QM conical intersection optimization and MM minimization for potential energy surfaces; the second one is sequential QM conical intersection optimization and MM sampling for potential of mean force surfaces, i.e., free energy surfaces. In such methods, the region where electronic structures change remarkably is placed into the QM subsystem, while the rest of the system is placed into the MM subsystem; thus, dimensionalities of gradient difference and nonadiabatic coupling vectors are decreased due to the relatively small QM subsystem. Furthermore, in comparison with the concurrent optimization scheme, sequential QM conical intersection optimization and MM minimization or sampling reduce the number of evaluations of gradient difference and nonadiabatic coupling vectors because these vectors need to be calculated only when the QM subsystem moves, independent of the MM minimization or sampling. Taken together, costly evaluations of gradient difference and nonadiabatic coupling vectors in solution or
Spectral bisection algorithm for solving Schrodinger equation using upper and lower solutions
Directory of Open Access Journals (Sweden)
Qutaibeh Deeb Katatbeh
2007-10-01
Full Text Available This paper establishes a new criteria for obtaining a sequence of upper and lower bounds for the ground state eigenvalue of Schr"odinger equation $ -Deltapsi(r+V(rpsi(r=Epsi(r$ in $N$ spatial dimensions. Based on this proposed criteria, we prove a new comparison theorem in quantum mechanics for the ground state eigenfunctions of Schrodinger equation. We determine also lower and upper solutions for the exact wave function of the ground state eigenfunctions using the computed upper and lower bounds for the eigenvalues obtained by variational methods. In other words, by using this criteria, we prove that the substitution of the lower(upper bound of the eigenvalue in Schrodinger equation leads to an upper(lower solution. Finally, two proposed iteration approaches lead to an exact convergent sequence of solutions. The first one uses Raielgh-Ritz theorem. Meanwhile, the second approach uses a new numerical spectral bisection technique. We apply our results for a wide class of potentials in quantum mechanics such as sum of power-law potentials in quantum mechanics.
Fast sweeping algorithm for accurate solution of the TTI eikonal equation using factorization
bin Waheed, Umair
2017-06-10
Traveltime computation is essential for many seismic data processing applications and velocity analysis tools. High-resolution seismic imaging requires eikonal solvers to account for anisotropy whenever it significantly affects the seismic wave kinematics. Moreover, computation of auxiliary quantities, such as amplitude and take-off angle, rely on highly accurate traveltime solutions. However, the finite-difference based eikonal solution for a point-source initial condition has an upwind source-singularity at the source position, since the wavefront curvature is large near the source point. Therefore, all finite-difference solvers, even the high-order ones, show inaccuracies since the errors due to source-singularity spread from the source point to the whole computational domain. We address the source-singularity problem for tilted transversely isotropic (TTI) eikonal solvers using factorization. We solve a sequence of factored tilted elliptically anisotropic (TEA) eikonal equations iteratively, each time by updating the right hand side function. At each iteration, we factor the unknown TEA traveltime into two factors. One of the factors is specified analytically, such that the other factor is smooth in the source neighborhood. Therefore, through the iterative procedure we obtain accurate solution to the TTI eikonal equation. Numerical tests show significant improvement in accuracy due to factorization. The idea can be easily extended to compute accurate traveltimes for models with lower anisotropic symmetries, such as orthorhombic, monoclinic or even triclinic media.
Zlotnik, V.A.; McGuire, V.L.
1998-01-01
Using the developed theory and modified Springer-Gelhar (SG) model, an identification method is proposed for estimating hydraulic conductivity from multi-level slug tests. The computerized algorithm calculates hydraulic conductivity from both monotonic and oscillatory well responses obtained using a double-packer system. Field verification of the method was performed at a specially designed fully penetrating well of 0.1-m diameter with a 10-m screen in a sand and gravel alluvial aquifer (MSEA site, Shelton, Nebraska). During well installation, disturbed core samples were collected every 0.6 m using a split-spoon sampler. Vertical profiles of hydraulic conductivity were produced on the basis of grain-size analysis of the disturbed core samples. These results closely correlate with the vertical profile of horizontal hydraulic conductivity obtained by interpreting multi-level slug test responses using the modified SG model. The identification method was applied to interpret the response from 474 slug tests in 156 locations at the MSEA site. More than 60% of responses were oscillatory. The method produced a good match to experimental data for both oscillatory and monotonic responses using an automated curve matching procedure. The proposed method allowed us to drastically increase the efficiency of each well used for aquifer characterization and to process massive arrays of field data. Recommendations generalizing this experience to massive application of the proposed method are developed.Using the developed theory and modified Springer-Gelhar (SG) model, an identification method is proposed for estimating hydraulic conductivity from multi-level slug tests. The computerized algorithm calculates hydraulic conductivity from both monotonic and oscillatory well responses obtained using a double-packer system. Field verification of the method was performed at a specially designed fully penetrating well of 0.1-m diameter with a 10-m screen in a sand and gravel alluvial
Sotoodeh, Pedram
This dissertation presents the design of a novel multi-level inverter with FACTS capability for small to mid-size (10-20kW) permanent-magnet wind installations using modular multi-level converter (MMC) topology. The aim of the work is to design a new type of inverter with D-STATCOM option to provide utilities with more control on active and reactive power transfer of distribution lines. The inverter is placed between the renewable energy source, specifically a wind turbine, and the distribution grid in order to fix the power factor of the grid at a target value, regardless of wind speed, by regulating active and reactive power required by the grid. The inverter is capable of controlling active and reactive power by controlling the phase angle and modulation index, respectively. The unique contribution of the proposed work is to combine the two concepts of inverter and D-STATCOM using a novel voltage source converter (VSC) multi-level topology in a single unit without additional cost. Simulations of the proposed inverter, with 5 and 11 levels, have been conducted in MATLAB/Simulink for two systems including 20 kW/kVAR and 250 W/VAR. To validate the simulation results, a scaled version (250 kW/kVAR) of the proposed inverter with 5 and 11 levels has been built and tested in the laboratory. Experimental results show that the reduced-scale 5- and 11-level inverter is able to fix PF of the grid as well as being compatible with IEEE standards. Furthermore, total cost of the prototype models, which is one of the major objectives of this research, is comparable with market prices.
Reconstruction of cylindrically layered media using an iterative algorithm with a stable solution
Institute of Scientific and Technical Information of China (English)
CHENG Ji-zhen; NIU Zuo-yuan; CHENG Chong-hu
2007-01-01
The reconstruction of cylindrically layered media is investigated in this article. The inverse problem is modeled using a source-type integral equation with a series of cylindrical waves as incidences, and a conventional Born iterative procedure is modified for solving the integral equation. In the modified iterative procedure, a conventional single-point approximation for the calculation of the field inside media is replaced by a multi-points approximation to improve the numerical stability of its solution. Numerical simulations for different permittivity distributions are demon- strated in terms of artificial scattering data with the procedure. The result shows that the procedure enjoys both accuracy and stability in the numerical computation.
Energy Technology Data Exchange (ETDEWEB)
Fischer, P.F. [Brown Univ., Providence, RI (United States)
1996-12-31
Efficient solution of the Navier-Stokes equations in complex domains is dependent upon the availability of fast solvers for sparse linear systems. For unsteady incompressible flows, the pressure operator is the leading contributor to stiffness, as the characteristic propagation speed is infinite. In the context of operator splitting formulations, it is the pressure solve which is the most computationally challenging, despite its elliptic origins. We seek to improve existing spectral element iterative methods for the pressure solve in order to overcome the slow convergence frequently observed in the presence of highly refined grids or high-aspect ratio elements.
Institute of Scientific and Technical Information of China (English)
LIChun-jing; GUChuan-qing
2003-01-01
Two efficient recursive algorithms epsilon-algorithm and eta-algorithm are introduced to compute the generalized inverse function-valued Pade approximants.The approximants were used to accelearte the convergence of the power with function-valued coefficinets and to estimate characteristic value of the integra equations.Famous Wynn identitles of the Pade appraxlmants is also established by means of the connection of two algorithms.
Developing the multi-level functioning interface framework for DER models
DEFF Research Database (Denmark)
Han, Xue; Bindner, Henrik W.; You, Shi
2013-01-01
The paper summarises several modelling applications of distributed energy resources (DERs) for various purposes, and describes the related operational issues regarding the complexity of the future distribution grid. Furthermore, a multi-level functioning interface framework is proposed for DER mo....... The information mapping for photovoltaic panel (PV) modelling is also provided as an example....
Device Independent Layout and Style Editing Using Multi-Level Style Sheets
Dees, Walter
This paper describes a layout and styling framework that is based on the multi-level style sheets approach. It shows some of the techniques that can be used to add layout and style information to a UI in a device-independent manner, and how to reuse the layout and style information to create user interfaces for different devices
A Bayesian Multi-Level Factor Analytic Model of Consumer Price Sensitivities across Categories
Duvvuri, Sri Devi; Gruca, Thomas S.
2010-01-01
Identifying price sensitive consumers is an important problem in marketing. We develop a Bayesian multi-level factor analytic model of the covariation among household-level price sensitivities across product categories that are substitutes. Based on a multivariate probit model of category incidence, this framework also allows the researcher to…
PENGEMBANGAN MEDIA LUBANG MULTI LEVEL UNTUK PEMBELAJARAN LEMPAR TANGKAP BOLA KECIL
Directory of Open Access Journals (Sweden)
Tri Aryo Trubus Anom
2017-02-01
Full Text Available This research aims to develop a media Hole Multi Level to capture the small ball throwing learning grade IV elementary school level that can increase students roll control. The model of the research is the development of research and data analysis in the form of a percentage of data types with a description of the qualitative and quantitative. Procedure development include; 1 Potential problems, 2 Data collection, 3 Early media product design Multi Level Hole, 4 Design Validation by expert penjas and learning experts, 5 Revision products I, 6 Trials I in MI Ma’arif NU Darmakradenan, 7 Product revision II, 8 Trial II at four elementary school in the village of Darmakradenan, 9 Product revision III, 10 And products. The results of expert validation against the media Pit Multi Level was 80%, I Test of 83,23%, and II trials of 85.97%. Those results can be concluded that the development of the media Pit Multi Level can be used to capture the small ball throwing learning grade IV elementary school level.
Graduate Attribute Attainment in a Multi-Level Undergraduate Geography Course
Mager, Sarah; Spronken-Smith, Rachel
2014-01-01
We investigated students' perceptions of graduate attributes in a multi-level (second and third year) geography course. A case study with mixed methodology was employed, with data collected through focus groups and a survey. We found that undergraduate geography students can identify the skills, knowledge and attributes that are developed through…
INVERTER MULTI LEVEL TIPE JEMBATAN SATU FASA TIGA TINGKAT DENGAN MIKROKONTROLER AT89S51
Directory of Open Access Journals (Sweden)
A. Warsito A. Warsito
2012-02-01
Full Text Available Inverter is a power electronics circuit which is used to convert DC voltage and current to AC voltage andcurrent. In conventional inverter, most commonly used, only has three level voltage, those are +Vdc, -Vdc,and zero. Meanwhile both square inverters and SWPM inverter has big harmonic distortion. In SPWMinverter scheme, high frequency switching must be used to minimize total harmonic distortion (THD. Multilevel inverter is a type of inverter that has more than one level of voltage and current output.The major advantages of multi level inverters are a good voltage waveform, small harmonic dirtortion,switching component operated under low frequency, and it can supply a big power.This paper will discuse the construction of single phase three level multi level inverters, hardware testinginclude output waveform THD, and the comparisson of multilevel inverter with other conventional invertersscheme suc as PWM inverters modulation, and square waveform inverter. Atmel’s AT89S51 microcontrollerused to control switching scheme in this multi level inverter. By this power electronic circuit, it is expected alow cost and reliable multi level inverters prototipe.
A Bayesian Multi-Level Factor Analytic Model of Consumer Price Sensitivities across Categories
Duvvuri, Sri Devi; Gruca, Thomas S.
2010-01-01
Identifying price sensitive consumers is an important problem in marketing. We develop a Bayesian multi-level factor analytic model of the covariation among household-level price sensitivities across product categories that are substitutes. Based on a multivariate probit model of category incidence, this framework also allows the researcher to…
A Multi-Level Analysis of Risk Factors for Campylobacter spp. in Broiler Chickens in Iceland
Introduction We carried out a longitudinal study of the broiler industry in Iceland between May 2001 and September 2004. Using multi-level statistical methods, our objective was to determine which aspects of the birds, their management and/or their housing may be most useful for applying interventi...
EU directives and multi-level governance - can lessons be drawn from cooperative federalism?
Vandamme, T.
2014-01-01
In this contribution, an attempt will be made to draw lines between the concepts of (cooperative) federalism, multi-level governance (MLG) and the European directive as a multi-tiered instrument. Can directives be regarded as federal by nature? And if so, what normative conclusions might one draw th
Evidencing Learning Outcomes: A Multi-Level, Multi-Dimensional Course Alignment Model
Sridharan, Bhavani; Leitch, Shona; Watty, Kim
2015-01-01
This conceptual framework proposes a multi-level, multi-dimensional course alignment model to implement a contextualised constructive alignment of rubric design that authentically evidences and assesses learning outcomes. By embedding quality control mechanisms at each level for each dimension, this model facilitates the development of an aligned…
An ANN Based Capicitor Voltage Balancing Method For Neutral Point Clamped Multi-Level Inverter
Directory of Open Access Journals (Sweden)
P.J.S. Praveen,
2015-11-01
Full Text Available Multi-level inverters are became popular for usage in medium voltage, low voltage power applications due to flexibility in control and better performance characteristics in terms of harmonic regulation. Neutral point clamped are popular as they require less number of sources as their input when compared with their counter parts i.e. cascaded multi-level inverters and found to be reliable when compared with flying capacitor based multi-level inverters. But when neutral clamped technologies are used for generation of three-phase voltages, the capacitors that are connected at input side experiences imbalance in their voltages, this makes neutral point clamped multi-level inverters less reliable. In the proposed work an attempt is made to study circuits that balances the capacitor voltages and a scheme is investigated for balancing the capacitor voltages. Method proposed in [1] uses PID controller for balancing the capacitor voltages. In this project PI based control scheme and artificial neural network (ANN based control scheme for the front end circuit shown in [1] are designed for achieving balance among the capacitor voltages. The proposed control scheme is simulated with the help of Simpowersystems block set and neural network toolbox of MATLAB software for different load conditions. Results obtained from ANN based controller and PI controller are presented.
Multi-level ILU-factorizations for eigenvalue computation and continuation
Wubs, F; Tiesinga, G.; Henry, D; Bergeon, A
2000-01-01
In recent years substantial progress has been made in the development of multi-level ILU-factorizations. In some cases, current versions already show (near) grid-independent convergence and therefore are attractive for very large problems. In this paper a variant called MRILU is described and applie
Multi-level Control Framework for Enhanced Flexibility of Active Distribution Network
DEFF Research Database (Denmark)
Nainar, Karthikeyan; Pokhrel, Basanta Raj; Pillai, Jayakrishnan Radhakrishna
2017-01-01
the selected control objectives and provides enhanced flexibility. The control architecture is supported by generation/load forecasting and distribution state estimation techniques to improve the controllability of the network. The multi-level control architecture consists of three levels of hierarchical...
Governing the energy challenge : Canada and Germany in a multi-level regional and global context
Energy Technology Data Exchange (ETDEWEB)
Eberlein, B. [York Univ., Toronto, ON (Canada). Schulich School of Business; Doern, G.B. [Carleton Univ., Ottawa, ON (Canada). School of Public Policy and Administration; Exeter Univ., (United Kingdom). Dept. of Politics] (eds.)
2009-07-01
This book features essays by leading energy and public policy specialists from Canada and Germany. It originated in the Transatlantic Energy Conference which was hosted by the Canadian Centre for German and European Studies at Toronto's York University in September 2005. The conference was attended by leading energy scholars and experts from Canadian and European universities, research institutes and governmental and non-governmental organizations. The purpose of this book was to compare the dynamics of multi-level energy regulatory governance in Germany and Canada, notably the energy policy challenges that include energy security, environmental sustainability and a competitive resource economy. Many strategies to produce more efficient and sustainable energy are presented in the book. Part 1 of the book focuses on the energy industry, with particular emphasise on electricity, nuclear energy and natural gas. Part 2 of the book focuses on domestic patterns of multi-level energy governance and regulation in the two countries. As a member of the European Union, Germany is more advanced in dealing with multi-level governmental and sustainability constraints than Canada is as a member of the North American Free Trade Agreement (NAFTA). The book focuses on the influence that the energy sector and multi-level institutional arrangements have on energy governance, with particular attention to the link between environmental study, climate change issues and economic market reforms. The growing differences between NAFTA and European Union member countries were highlighted. refs., tabs., figs.
Analytic Solution for Estimating the Tracking Capability of the RLS Algorithm for Smart Antenna
Institute of Scientific and Technical Information of China (English)
GU Qijun; JIAO Bingli
2001-01-01
Although smart antenna will be intro-duced in the third generation mobile communicationfor its great improvements on the capacity, it is not asimple task to commercialize this technique to prac-tical fields, mainly because the overall procedure re-quires an enormous amount of computation. For mostadaptive processors, the calculation burden can be at-tributed to the calculation complexity required by thealgorithm at each iteration and the iteration rate re-quired by adaptivity of system in time-varying chan-nels. The presented paper presents an analytic solu-tion for estimating the tracking capability of the Re-cursive Least Square (RLS). This approach is formedby the simulation results.
Java Based Computer Algorithms for the Solution of a Business Mathematics Model
Directory of Open Access Journals (Sweden)
A. D. Chinedu
2014-10-01
Full Text Available A novel approach is proposed as a framework for working out uncertainties associated with decisions between the choices of leasing and procurement of capital assets in a manufacturing industry. The mathematical concept of the tool is discussed while the technique adopted is much simpler to implement and initialize. The codes were developed in Java-programming language and text-run and executed on a computer system running on Windows 7 operating system. This was done in order to solve a model that illustrates a case study in actuarial mathematics. Meanwhile the solution obtained proves to be stable and proffers to suit the growing frenzy for software for similar recurring cases in business. In addition, it speeds up the computational results. The results obtained using the empirical method is compared with the output and adjudged excellent in terms of accuracy and adoption.
Algorithms of common solutions to quasi variational inclusion and fixed point problems
Institute of Scientific and Technical Information of China (English)
ZHANG Shi-sheng; LEE Joseph H. W.; CHAN Chi Kin
2008-01-01
The purpose of this paper is to present an iterative scheme for finding a common element of the set of solutions to the variational inclusion problem with multi-valued maximal monotone mapping and inverse-strongly monotone mappings and the set of fixed points of nonexpansive mappings in Hilbert space. Under suitable conditions, some strong convergence theorems for approximating this common elements are proved. The results presented in the paper not only improve and extend the main results in Korpelevich (Ekonomika i Matematicheskie Metody, 1976, 12(4):747-756), but also extend and replenish the corresponding results obtained by Iiduka and Takahashi (Nonlinear Anal TMA, 2005, 61(3):341-350), Takahashi and Toyoda (J Optim Theory Appl, 2003,118(2):417-428), Nadezhkina and Takahashi (J Optim Theory Appl, 2006, 128(1):191-201), and Zeng and Yao (Taiwanese Journal of Mathematics, 2006, 10(5):1293-1303).
Directory of Open Access Journals (Sweden)
Hadi Mokhtari
2013-01-01
Full Text Available In this paper, the problem of received order scheduling by a manufacturer, with the measure of maximum completion times of orders, has been formulated and then an analytical approach has been devised for its solution. At the beginning of a planning period, the manufacturer receives a number of orders from customers, each of which requires two different stages for processing. In order to minimize the work in process inventories, the no-wait condition between two operations of each order is regarded. Then, the equality of obtained schedules is proved by machine idle time minimization, as objective, with the schedules obtained by maximum completion time minimization. A concept entitled “Order pairing” has been defined and an algorithm for achieving optimal order pairs which is based on symmetric assignment problem has been presented. Using the established order pairs, an upper bound has been developed based on contribution of every order pair out of total machines idle time. Out of different states of improving upper bound, 12 potential situations of order pairs sequencing have been also evaluated and then the upper bound improvement has been proved in each situation, separately. Finally, a heuristic algorithm has been developed based on attained results of pair improvement and a case study in printing industry has been investigated and analyzed to approve its applicability.
Zheng, Ying; Yeh, Chen-Wei; Yang, Chi-Da; Jang, Shi-Shang; Chu, I-Ming
2007-08-31
Biological information generated by high-throughput technology has made systems approach feasible for many biological problems. By this approach, optimization of metabolic pathway has been successfully applied in the amino acid production. However, in this technique, gene modifications of metabolic control architecture as well as enzyme expression levels are coupled and result in a mixed integer nonlinear programming problem. Furthermore, the stoichiometric complexity of metabolic pathway, along with strong nonlinear behaviour of the regulatory kinetic models, directs a highly rugged contour in the whole optimization problem. There may exist local optimal solutions wherein the same level of production through different flux distributions compared with global optimum. The purpose of this work is to develop a novel stochastic optimization approach-information guided genetic algorithm (IGA) to discover the local optima with different levels of modification of the regulatory loop and production rates. The novelties of this work include the information theory, local search, and clustering analysis to discover the local optima which have physical meaning among the qualified solutions.
Energy Technology Data Exchange (ETDEWEB)
Jollands, Nigel; Gasc, Emilien; Pasquier, Sara Bryan
2009-12-15
Despite creating a plethora of national and international regulations and voluntary programmes to improve energy efficiency, countries are far from achieving full energy efficiency potential across all sectors of the economy. One major challenge, among numerous barriers, is policy implementation. One strategy that many national governments and international organisations have used to address the implementation issue is to engage regional and local authorities. To that end, many programmes have been created that foster energy efficiency action and collaboration across levels of government. The aim of this report is to identify trends and detail recent developments in multi-level governance in energy efficiency (MLGEE). By sharing lessons learned from daily practitioners in the field, the IEA hopes energy efficiency policy makers at all levels of government will be able to identify useful multilevel governance (MLG) practices across geographical and political contexts and use these to design robust programmes; modify existing programmes, and connect and share experiences with other policy makers in this field.
Multi-level manual and autonomous control superposition for intelligent telerobot
Hirai, Shigeoki; Sato, T.
1989-01-01
Space telerobots are recognized to require cooperation with human operators in various ways. Multi-level manual and autonomous control superposition in telerobot task execution is described. The object model, the structured master-slave manipulation system, and the motion understanding system are proposed to realize the concept. The object model offers interfaces for task level and object level human intervention. The structured master-slave manipulation system offers interfaces for motion level human intervention. The motion understanding system maintains the consistency of the knowledge through all the levels which supports the robot autonomy while accepting the human intervention. The superposing execution of the teleoperational task at multi-levels realizes intuitive and robust task execution for wide variety of objects and in changeful environment. The performance of several examples of operating chemical apparatuses is shown.
Multi-level denoising and enhancement method based on wavelet transform for mine monitoring
Institute of Scientific and Technical Information of China (English)
Yanqin Zhao
2013-01-01
Based on low illumination and a large number of mixed noises contained in coal mine,denoising with one method usually cannot achieve good results,So a multi-level image denoising method based on wavelet correlation relevant inter-scale is presented.Firstly,we used directional median filter to effectively reduce impulse noise in the spatial domain,which is the main cause of noise in mine.Secondly,we used a Wiener filtration method to mainly reduce the Gaussian noise,and then finally used a multi-wavelet transform to minimize the remaining noise of low-light images in the transform domain.This multi-level image noise reduction method combines spatial and transform domain denoising to enhance benefits,and effectively reduce impulse noise and Gaussian noise in a coal mine,while retaining good detailed image characteristics of the underground for improving quality of images with mixing noise and effective low-light environment.
Multi-level Split Cord Malformation: Do We Need a New Classification?
Directory of Open Access Journals (Sweden)
Gmaan A Alzhrani
2014-01-01
Full Text Available Split cord malformations (SCMs are thought to be rare abnormalities representing 3.8-5% of all spinal cord anomalies. The prevalence is estimated to be 1 in 5499 live births (0.02%, with a slight female predominance (1.3:1. Although the estimates of prevalence vary, Type I SCM occurs more frequently than Type II SCM. In this paper, we are reporting the clinical presentation and imaging findings of multi-level SCM in a 27-year-old male. A literature review of the embryological background of SCM and pathological hypothesis for this entity is provided. A systematic review has been conducted to identify multi-level SCM cases reported in the literature, followed by proposing a new classification system to further our understanding and management of SCMs.
Loose architecture of multi-level massive geospatial data based on virtual quadtree
Institute of Scientific and Technical Information of China (English)
2008-01-01
This paper proposed a virtual quadtree (VQT) based loose architecture of multi-level massive geospatial data for integrating massive geospatial data dispersed in the departments of different hierarchies in the same sector into a unified GIS (Geographic Information System) platform. By virtualizing the nodes of the quad-tree,the VQT separates the structure of data organization from data storage,and screens the difference between the data storage in local computer and in the re-mote computers in network environment. And by mounting,VQT easily integrates the data from the remote computers into the local VQT so as to implement seam-less integration of distributed multi-level massive geospatial data. Based on that mode,the paper built an application system with geospatial data over 1200 GB distributed in 12 servers deployed in 12 cities. The experiment showed that all data can be seamlessly rapidly traveled and performed zooming in and zooming out smoothly.
Domain decomposition, multi-level integration and exponential noise reduction in lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Ce, Marco [Scuola Normale Superiore, Pisa (Italy); INFN, Sezione di Pisa (Italy); Giusti, Leonardo [Univ. di Milano-Bicocca (Italy). Dipt. di Fisica; INFN, Sezione di Milano-Bicocca (Italy); Schaefer, Stefan [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC
2016-01-15
We explore the possibility of computing fermionic correlators on the lattice by combining a domain decomposition with a multi-level integration scheme. The quark propagator is expanded in series of terms with a well defined hierarchical structure. The higher the order of a term, the (exponentially) smaller its magnitude, the less local is its dependence on the gauge field. Once inserted in a Wick contraction, the gauge-field dependence of the terms in the resulting series can be factorized so that it is suitable for multi-level Monte Carlo integration. We test the strategy in quenched QCD by computing the disconnected correlator of two flavor-diagonal pseudoscalar densities, and a nucleon two-point function. In either cases we observe a significant exponential increase of the signal-to-noise ratio.
Habit, custom, and power: a multi-level theory of population health.
Zimmerman, Frederick J
2013-03-01
In multi-level theory, individual behavior flows from cognitive habits, either directly through social referencing, rules of thumb, or automatic behaviors; or indirectly through the shaping of rationality itself by framing or heuristics. Although behavior does not arise from individually rational optimization, it generally appears to be rational, because the cognitive habits that guide behavior evolve toward optimality. However, power imbalances shaped by particular social, political, and economic structures can distort this evolution, leading to individual behavior that fails to maximize individual or social well-being. Replacing the dominant rational-choice paradigm with a multi-level theoretical paradigm involving habit, custom, and power will enable public health to engage in rigorous new areas of research.
Neural Network Based Multi-level Fuzzy Evaluation Model for Mechanical Kinematic Scheme
Institute of Scientific and Technical Information of China (English)
BO Ruifeng; LI Ruiqin
2006-01-01
To implement a quantificational evaluation for mechanical kinematic scheme more effectively, a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly, the structure of evaluation model is constructed according to evaluation indicator system. Then evaluation samples are generated and provided to train this model. Thus it can reflect the relation between attributive value and evaluation result, as well as the weight of evaluation indicator. Once evaluation indicators of each candidate are fuzzily quantified and fed into the trained network model, the corresponding evaluation result is outputted and the best alternative can be selected. Under this model, expert knowledge can be effectively acquired and expressed, and the quantificational evaluation can be implemented for kinematic scheme with multi-level evaluation indicator system. Several key problems on this model are discussed and an illustration has demonstrated that this model is feasible and can be regarded as a new idea for solving kinematic scheme evaluation.
Multi-level Split Cord Malformation: Do We Need a New Classification?
Alzhrani, Gmaan A; Al-Jehani, Hosam M; Melançon, Denis
2014-01-01
Split cord malformations (SCMs) are thought to be rare abnormalities representing 3.8-5% of all spinal cord anomalies. The prevalence is estimated to be 1 in 5499 live births (0.02%), with a slight female predominance (1.3:1). Although the estimates of prevalence vary, Type I SCM occurs more frequently than Type II SCM. In this paper, we are reporting the clinical presentation and imaging findings of multi-level SCM in a 27-year-old male. A literature review of the embryological background of SCM and pathological hypothesis for this entity is provided. A systematic review has been conducted to identify multi-level SCM cases reported in the literature, followed by proposing a new classification system to further our understanding and management of SCMs.
Institute of Scientific and Technical Information of China (English)
程晓良; 徐渊辑; 孟炳泉
2005-01-01
An algorithm for numerical solution of discrete Hamilton-Jacobi-Bellman equations is proposed.The method begins with a suitable initial guess value of the solution,then finds a suitable matrix to linearize the system and constructs an iteration algorithm to generate the monotone sequence.The convergence of the algorithm for nonlinear discrete Hamilton-Jacobi-Bellman equations is proved.Some numerical examples are presented to confirm the effciency of this algorithm.
A System for Generating Operational Sketches Based on the Multi-level Graphic Library
Institute of Scientific and Technical Information of China (English)
BAO Zhen-qiang; WANG Ning-sheng
2001-01-01
This paper points out the limitations of both parametric and geometric model methodscommonly applied to generate operational sketches in CAPP. The ideas of multi-level graphic library areintroduced and a new generative method based on this library which combines parametric method withgeometric model method is presented. The principles and characteristics of the construction of the library aredescribed in detail and the feature data structure corresponding with the library is also presented.
DEFF Research Database (Denmark)
Margheritini, Lucia; Victor, L.; Kofoed, Jens Peter
2009-01-01
In multi-level wave energy converters the water from incoming waves is stored in reservoirs one on top of the other. Prevision formula for the overtopping flow rates in the individual reservoirs is fundamental for dimensioning correctly the turbines and optimizing the device. Having a number...... words, the opening between two consecutive reservoirs. 13 different geometries have been tested in 2D irregular waves and a new formulation for prediction of overtopping in multilevel structures is presented....
A Formal Model of Trust Chain based on Multi-level Security Policy
Directory of Open Access Journals (Sweden)
Kong Xiangying
2013-07-01
Full Text Available Trust chain is the core technology of trusted computing. A formal model of trust chain based on finite state automata theory is proposed. We use communicating sequential processes to describe the system state transition in trust chain and by combining with multi-level security strategy give the definition of trust system and trust decision theorem of trust chain transfer which is proved meantime. Finally, a prototype system is given to show the efficiency of the model.
Happaerts, Sander
2013-01-01
This paper analyzes subnational climate policies in Belgium as a crucial case of multi-level policy-making in Europe. In Belgian federalism, the subnational governments have a large autonomy to conduct their own climate policies, while the scope to act at the federal level is very limited. Moreover, the federal system had produced complex and ineffective coordination patterns, where the federal and the subnational governments each have the possibility to block agreements, e.g. on the intra-Be...
Li, Xiucan; Wang, Yiguo; Zhao, Yongfei; Liu, Jianheng; Xiao, Songhua; Mao, Keya
2017-05-11
A unique case report. A three-dimensional (3D) printing technology is proposed for reconstructing multi-level cervical spine (C2-C4) after resection of metastatic papillary thyroid carcinoma in a middle-age female patient. Papillary thyroid carcinoma is a malignant neoplasm with a relatively favorable prognosis. A metastatic lesion in multi-level cervical spine (C2-C4) destroys neurological functions and causes local instability. Radical excision of the metastasis and reconstruction of the cervical vertebrae sequence conforms with therapeutic principles, while the special-shaped multi-level upper-cervical spine requires personalized implants. 3D printing is an additive manufacturing technology that produces personalized products by accurately layering material under digital model control via a computer. Reporting of this recent technology for reconstructing multi-level cervical spine (C2-C4) is rare in the literature. Anterior-posterior surgery was performed in one stage. Radical resection of the metastatic lesion (C2-C4) and thyroid gland, along with insertion of a personalized implant manufactured by 3D printing technology, were performed to rebuild the cervical spine sequences. The porous implant was printed in Ti6AL4 V with perfect physicochemical properties and biological performance, such as biocompatibility and osteogenic activity. Finally, lateral mass screw fixation was performed via a posterior approach. Patient neurological function gradually improved after the surgery. The patient received 11/17 on the Japanese Orthopedic Association scale and ambulated with a personalized skull-neck-thorax orthosis on postoperative day 11. She received radioiodine I therapy. The plane X-rays and computed tomography revealed no implant displacement or subsidence at the 12-month follow-up mark. The presented case substantiates the use of 3D printing technology, which enables the personalization of products to solve unconventional problems in spinal surgery. 5.
DEFF Research Database (Denmark)
Liu, Hui; Ma, Ke; Loh, Poh Chiang;
2016-01-01
The modular multi-level converter has become an interesting candidate in high-voltage DC systems due to its higher voltage levels and modular construction. Low-voltage ride-through is an important grid requirement for modular multi-level converter–high-voltage DC since not only causes control cha...... be of importance for the design of the cooling system....
Directory of Open Access Journals (Sweden)
Daniel J. Garcia
2015-07-01
Full Text Available The water footprint of energy systems must be considered, as future water scarcity has been identified as a major concern. This work presents a general life cycle network modeling and optimization framework for energy-based products and processes using a functional unit of liters of water consumed in the processing pathway. We analyze and optimize the water-energy nexus over the objectives of water footprint minimization, maximization of economic output per liter of water consumed (economic efficiency of water, and maximization of energy output per liter of water consumed (energy efficiency of water. A mixed integer, multiobjective nonlinear fractional programming (MINLFP model is formulated. A mixed integer linear programing (MILP-based branch and refine algorithm that incorporates both the parametric algorithm and nonlinear programming (NLP subproblems is developed to boost solving efficiency. A case study in bioenergy is presented, and the water footprint is considered from biomass cultivation to biofuel production, providing a novel perspective into the consumption of water throughout the value chain. The case study, optimized successively over the three aforementioned objectives, utilizes a variety of candidate biomass feedstocks to meet primary fuel products demand (ethanol, diesel, and gasoline. A minimum water footprint of 55.1 ML/year was found, economic efficiencies of water range from −$1.31/L to $0.76/L, and energy efficiencies of water ranged from 15.32 MJ/L to 27.98 MJ/L. These results show optimization provides avenues for process improvement, as reported values for the energy efficiency of bioethanol range from 0.62 MJ/L to 3.18 MJ/L. Furthermore, the proposed solution approach was shown to be an order of magnitude more efficient than directly solving the original MINLFP problem with general purpose solvers.
Multi-stage decoding for multi-level block modulation codes
Lin, Shu
1991-01-01
In this paper, we investigate various types of multi-stage decoding for multi-level block modulation codes, in which the decoding of a component code at each stage can be either soft-decision or hard-decision, maximum likelihood or bounded-distance. Error performance of codes is analyzed for a memoryless additive channel based on various types of multi-stage decoding, and upper bounds on the probability of an incorrect decoding are derived. Based on our study and computation results, we find that, if component codes of a multi-level modulation code and types of decoding at various stages are chosen properly, high spectral efficiency and large coding gain can be achieved with reduced decoding complexity. In particular, we find that the difference in performance between the suboptimum multi-stage soft-decision maximum likelihood decoding of a modulation code and the single-stage optimum decoding of the overall code is very small: only a fraction of dB loss in SNR at the probability of an incorrect decoding for a block of 10(exp -6). Multi-stage decoding of multi-level modulation codes really offers a way to achieve the best of three worlds, bandwidth efficiency, coding gain, and decoding complexity.
Shi, Qi; Abdel-Aty, Mohamed; Yu, Rongjie
2016-03-01
In traffic safety studies, crash frequency modeling of total crashes is the cornerstone before proceeding to more detailed safety evaluation. The relationship between crash occurrence and factors such as traffic flow and roadway geometric characteristics has been extensively explored for a better understanding of crash mechanisms. In this study, a multi-level Bayesian framework has been developed in an effort to identify the crash contributing factors on an urban expressway in the Central Florida area. Two types of traffic data from the Automatic Vehicle Identification system, which are the processed data capped at speed limit and the unprocessed data retaining the original speed were incorporated in the analysis along with road geometric information. The model framework was proposed to account for the hierarchical data structure and the heterogeneity among the traffic and roadway geometric data. Multi-level and random parameters models were constructed and compared with the Negative Binomial model under the Bayesian inference framework. Results showed that the unprocessed traffic data was superior. Both multi-level models and random parameters models outperformed the Negative Binomial model and the models with random parameters achieved the best model fitting. The contributing factors identified imply that on the urban expressway lower speed and higher speed variation could significantly increase the crash likelihood. Other geometric factors were significant including auxiliary lanes and horizontal curvature.
Lomsky-Feder, Edna; Sasson-Levy, Orna
2015-03-01
With the growing elusiveness of the state apparatus in late modernity, military service is one of the last institutions to be clearly identified with the state, its ideologies and its policies. Therefore, negotiations between the military and its recruits produce acting subjects of citizenship with long-lasting consequences. Arguing that these negotiations are regulated by multi-level (civic, group, and individual) contracts, we explore the various meanings that these contracts obtain at the intersectionality of gender, class, and ethnicity; and examine how they shape the subjective experience of soldierhood and citizenship. More particularly, we analyse the meaning of military service in the retrospective life stories of Israeli Jewish women from various ethno-class backgrounds who served as army secretaries - a low-status, feminine gender-typed occupation within a hyper-masculine organization. Findings reveal that for women of the lower class, the organizing cultural schema of the multi-level contract is that of achieving respectability through military service, which means being included in the national collective. Conversely, for middle-class women, it is the sense of entitlement that shapes their contract with the military, which they expect to signify and maintain their privileged status. Thus, while for the lower class, the multi-level contract is about inclusion within the boundaries of the national collective, for the dominant groups, this contract is about reproducing social class hierarchies within national boundaries. © London School of Economics and Political Science 2014.
Multi-level governance of forest resources (Editorial to the special feature
Directory of Open Access Journals (Sweden)
Esther Mwangi
2012-08-01
Full Text Available A major challenge for many researchers and practitioners relates to how to recognize and address cross-scale dynamics in space and over time in order to design and implement effective governance arrangements. This editorial provides an overview of the concept of multi-level governance (MLG. In particular we highlight definitional issues, why the concept matters as well as more practical concerns related to the processes and structure of multi-level governance. It is increasingly clear that multi-level governance of forest resources involves complex interactions of state, private and civil society actors at various levels, and institutions linking higher levels of social and political organization. Local communities are increasingly connected to global networks and influences. This creates new opportunities to learn and address problems but may also introduce new pressures and risks. We conclude by stressing the need for a much complex approach to the varieties of MLG to better understand how policies work as instruments of governance and to organize communities within systems of power and authority.
A Multi-level Fuzzy Evaluation Method for Smart Distribution Network Based on Entropy Weight
Li, Jianfang; Song, Xiaohui; Gao, Fei; Zhang, Yu
2017-05-01
Smart distribution network is considered as the future trend of distribution network. In order to comprehensive evaluate smart distribution construction level and give guidance to the practice of smart distribution construction, a multi-level fuzzy evaluation method based on entropy weight is proposed. Firstly, focus on both the conventional characteristics of distribution network and new characteristics of smart distribution network such as self-healing and interaction, a multi-level evaluation index system which contains power supply capability, power quality, economy, reliability and interaction is established. Then, a combination weighting method based on Delphi method and entropy weight method is put forward, which take into account not only the importance of the evaluation index in the experts’ subjective view, but also the objective and different information from the index values. Thirdly, a multi-level evaluation method based on fuzzy theory is put forward. Lastly, an example is conducted based on the statistical data of some cites’ distribution network and the evaluation method is proved effective and rational.
Rahman, Md. Saifur; Lee, Yiu-Yin
2017-10-01
In this study, a new modified multi-level residue harmonic balance method is presented and adopted to investigate the forced nonlinear vibrations of axially loaded double beams. Although numerous nonlinear beam or linear double-beam problems have been tackled and solved, there have been few studies of this nonlinear double-beam problem. The geometric nonlinear formulations for a double-beam model are developed. The main advantage of the proposed method is that a set of decoupled nonlinear algebraic equations is generated at each solution level. This heavily reduces the computational effort compared with solving the coupled nonlinear algebraic equations generated in the classical harmonic balance method. The proposed method can generate the higher-level nonlinear solutions that are neglected by the previous modified harmonic balance method. The results from the proposed method agree reasonably well with those from the classical harmonic balance method. The effects of damping, axial force, and excitation magnitude on the nonlinear vibrational behaviour are examined.
Liu, Peng; Li, Chen; Wang, Dunyou
2017-09-25
The Cl(-) + CH3I → CH3Cl + I(-) reaction in water was studied using combined multi-level quantum mechanism theories and molecular mechanics with an explicit water solvent model. The study shows a significant influence of aqueous solution on the structures of the stationary points along the reaction pathway. A detailed, atomic-level evolution of the reaction mechanism shows a concerted one-bond-broken and one-bond-formed mechanism, as well as a synchronized charge-transfer process. The potentials of mean force calculations with the CCSD(T) and DFT treatments of the solute produce a free activation barrier at 24.5 kcal/mol and 19.0 kcal/mol respectively, which agrees with the experimental one at 22.0 kcal/mol. The solvent effects have also been quantitatively analyzed: in total, the solvent effects raise the activation energy by 20.2 kcal/mol, which shows a significant impact on this reaction in water.
Gong, Yi-long; Yan, Li
2015-05-01
The present paper proposes a new building change detection method combining Lidar point cloud with aerial image, using multi-level rules classification algorithm, to solve building change detection problem between these two kinds of heterogeneous data. Then, a morphological post-processing method combined with area threshold is proposed. Thus, a complete building change detection processing flow that can be applied to actual production is proposed. Finally, the effectiveness of the building change detection method is evaluated, processing the 2010 airborne LiDAR point cloud data and 2009 high resolution aerial image of Changchun City, Jilin province, China; in addition, compared with the object-oriented building change detection method based on support vector machine (SVM) classification, more analysis and evaluation of the suggested method is given. Experiment results show that the performance of the proposed building change detection method is ideal. Its Kappa index is 0. 90, and correctness is 0. 87, which is higher than the object-oriented building change detection method based on SVM classification.
Christen, Matthias; Del Medico, Luca; Christen, Heinz; Christen, Beat
2017-01-01
Recent advances in lower-cost DNA synthesis techniques have enabled new innovations in the field of synthetic biology. Still, efficient design and higher-order assembly of genome-scale DNA constructs remains a labor-intensive process. Given the complexity, computer assisted design tools that fragment large DNA sequences into fabricable DNA blocks are needed to pave the way towards streamlined assembly of biological systems. Here, we present the Genome Partitioner software implemented as a web-based interface that permits multi-level partitioning of genome-scale DNA designs. Without the need for specialized computing skills, biologists can submit their DNA designs to a fully automated pipeline that generates the optimal retrosynthetic route for higher-order DNA assembly. To test the algorithm, we partitioned a 783 kb Caulobacter crescentus genome design. We validated the partitioning strategy by assembling a 20 kb test segment encompassing a difficult to synthesize DNA sequence. Successful assembly from 1 kb subblocks into the 20 kb segment highlights the effectiveness of the Genome Partitioner for reducing synthesis costs and timelines for higher-order DNA assembly. The Genome Partitioner is broadly applicable to translate DNA designs into ready to order sequences that can be assembled with standardized protocols, thus offering new opportunities to harness the diversity of microbial genomes for synthetic biology applications. The Genome Partitioner web tool can be accessed at https://christenlab.ethz.ch/GenomePartitioner.
Directory of Open Access Journals (Sweden)
Sara Nakhjirkan
2017-09-01
in green supply chain. Vehicle routing between distribution centres and customers has been considered in the model. Establishment place of distribution centres among potential places is determined by the model. The distributors use continuous review policy (r, Q to control the inventory. The proposed model object is to find an optimal supply chain with minimum costs. To validate the proposed model and measure its compliance with real world problems, GAMS IDE/Cplex has been used. In order to measure the efficiency of the proposed model in large scale problems, a genetic algorithm has been used. The results confirm the efficiency of the proposed model as a practical tool for decision makers to solve location-inventory-routing problems in green supply chain. The proposed GA could reduce the solving time by 85% while reaching on the average 97% of optimal solution compared with exact method.
Walker, Joel W.
2014-08-01
The M T2, or "s-transverse mass", statistic was developed to associate a parent mass scale to a missing transverse energy signature, given that escaping particles are generally expected in pairs, while collider experiments are sensitive to just a single transverse momentum vector sum. This document focuses on the generalized extension of that statistic to asymmetric one- and two-step decay chains, with arbitrary child particle masses and upstream missing transverse momentum. It provides a unified theoretical formulation, complete solution classification, taxonomy of critical points, and technical algorithmic prescription for treatment of the event scale. An implementation of the described algorithm is available for download, and is also a deployable component of the author's selection cut software package AEAC uS (Algorithmic Event Arbiter and C ut Selector). appendices address combinatoric event assembly, algorithm validation, and a complete pseudocode.
Multi level optimization of burnable poison utilization for advanced PWR fuel management
Yilmaz, Serkan
The objective of this study was to develop an unique methodology and a practical tool for designing burnable poison (BP) pattern for a given PWR core. Two techniques were studied in developing this tool. First, the deterministic technique called Modified Power Shape Forced Diffusion (MPSFD) method followed by a fine tuning algorithm, based on some heuristic rules, was developed to achieve this goal. Second, an efficient and a practical genetic algorithm (GA) tool was developed and applied successfully to Burnable Poisons (BPs) placement optimization problem for a reference Three Mile Island-1 (TMI-1) core. This thesis presents the step by step progress in developing such a tool. The developed deterministic method appeared to perform as expected. The GA technique produced excellent BP designs. It was discovered that the Beginning of Cycle (BOC) Kinf of a BP fuel assembly (FA) design is a good filter to eliminate invalid BP designs created during the optimization process. By eliminating all BP designs having BOC Kinf above a set limit, the computational time was greatly reduced since the evaluation process with reactor physics calculations for an invalid solution is canceled. Moreover, the GA was applied to develop the BP loading pattern to minimize the total Gadolinium (Gd) amount in the core together with the residual binding at End-of-Cycle (EOC) and to keep the maximum peak pin power during core depletion and Soluble boron concentration at BOC both less than their limit values. The number of UO2/Gd2O3 pins and Gd 2O3 concentrations for each fresh fuel location in the core are the decision variables and the total amount of the Gd in the core and maximum peak pin power during core depletion are in the fitness functions. The use of different fitness function definition and forcing the solution movement towards to desired region in the solution space accelerated the GA runs. Special emphasize is given to minimizing the residual binding to increase core lifetime as
Examining multi-level effects on corporate social responsibility and irresponsibility
Directory of Open Access Journals (Sweden)
Mazzei Matthew J.
2015-10-01
Full Text Available What influences firms to engage in socially responsible (irresponsible activities? Corporate social responsibility (CSR, the efforts of firms to create a positive and desirable impact on society, and corporate social irresponsibility (CSI, contrary actions of unethical behavior that negatively influence society, have become an important focus of discussion for both corporations and scholars. Despite this interest, our understanding of organizations’ socially responsible (irresponsible actions and their antecedents is still developing. A dearth of knowledge about the multi-level nature of the drivers of CSR and CSI continues to exist. Utilizing a longitudinal sample composed of 899 firms in 66 industries, we follow a prominent model to empirically examine industry-, firm-, and individual-level effects on CSR and CSI. Employing variance decomposition analysis, our results confirm that all three levels of investigation do indeed influence CSR and CSI. More substantively, our analysis estimates the magnitude of the effects attributable to each of the three levels for both CSR and CSI. We also compare multi-level influences on two separate CSR strategies, those targeting primary stakeholders (strategic CSR and those targeting secondary stakeholders (social CSR. We find greater industry- and firmlevel effects on social CSR, and higher individual-level effects on strategic CSR. Our results build on the conceptual work of previous authors by providing empirical analyses to confirm multilevel influences on CSR and extending prior multi-level theory to the concept of CSI. Further, we add to the emerging literature regarding stakeholder demands by examining the various influences on CSR strategies targeting different stakeholder groups.
Push pull microfluidics on a multi-level 3D CD.
Thio, Tzer Hwai Gilbert; Ibrahim, Fatimah; Al-Faqheri, Wisam; Moebius, Jacob; Khalid, Noor Sakinah; Soin, Norhayati; Kahar, Maria Kahar Bador Abdul; Madou, Marc
2013-08-21
A technique known as thermo-pneumatic (TP) pumping is used to pump fluids on a microfluidic compact disc (CD) back towards the CD center against the centrifugal force that pushes liquids from the center to the perimeter of the disc. Trapped air expands in a TP air chamber during heating, and this creates positive pressure on liquids located in chambers connected to that chamber. While the TP air chamber and connecting channels are easy to fabricate in a one-level CD manufacturing technique, this approach provides only one way pumping between two chambers, is real-estate hungry and leads to unnecessary heating of liquids in close proximity to the TP chamber. In this paper, we present a novel TP push and pull pumping method which allows for pumping of liquid in any direction between two connected liquid chambers. To ensure that implementation of TP push and pull pumping also addresses the issue of space and heating challenges, a multi-level 3D CD design is developed, and localized forced convection heating, rather than infra-red (IR) is applied. On a multi-level 3D CD, the TP features are placed on a top level separate from the rest of the microfluidic processes that are implemented on a lower separate level. This approach allows for heat shielding of the microfluidic process level, and efficient usage of space on the CD for centrifugal handling of liquids. The use of localized forced convection heating, rather than infra-red (IR) or laser heating in earlier implementations allows not only for TP pumping of liquids while the CD is spinning but also makes heat insulation for TP pumping and other fluidic functions easier. To aid in future implementations of TP push and pull pumping on a multi-level 3D CD, study on CD surface heating is also presented. In this contribution, we also demonstrate an advanced application of pull pumping through the implementation of valve-less switch pumping.
Overweight and obesity in India: policy issues from an exploratory multi-level analysis.
Siddiqui, Md Zakaria; Donato, Ronald
2016-06-01
This article analyses a nationally representative household dataset-the National Family Health Survey (NFHS-3) conducted in 2005 to 2006-to examine factors influencing the prevalence of overweight/obesity in India. The dataset was disaggregated into four sub-population groups-urban and rural females and males-and multi-level logit regression models were used to estimate the impact of particular covariates on the likelihood of overweight/obesity. The multi-level modelling approach aimed to identify individual and macro-level contextual factors influencing this health outcome. In contrast to most studies on low-income developing countries, the findings reveal that education for females beyond a particular level of educational attainment exhibits a negative relationship with the likelihood of overweight/obesity. This relationship was not observed for males. Muslim females and all Sikh sub-populations have a higher likelihood of overweight/obesity suggesting the importance of socio-cultural influences. The results also show that the relationship between wealth and the probability of overweight/obesity is stronger for males than females highlighting the differential impact of increasing socio-economic status on gender. Multi-level analysis reveals that states exerted an independent influence on the likelihood of overweight/obesity beyond individual-level covariates, reflecting the importance of spatially related contextual factors on overweight/obesity. While this study does not disentangle macro-level 'obesogenic' environmental factors from socio-cultural network influences, the results highlight the need to refrain from adopting a 'one size fits all' policy approach in addressing the overweight/obesity epidemic facing India. Instead, policy implementation requires a more nuanced and targeted approach to incorporate the growing recognition of socio-cultural and spatial contextual factors impacting on healthy behaviours.
Munhoven, G.
2013-08-01
The total alkalinity-pH equation, which relates total alkalinity and pH for a given set of total concentrations of the acid-base systems that contribute to total alkalinity in a given water sample, is reviewed and its mathematical properties established. We prove that the equation function is strictly monotone and always has exactly one positive root. Different commonly used approximations are discussed and compared. An original method to derive appropriate initial values for the iterative solution of the cubic polynomial equation based upon carbonate-borate-alkalinity is presented. We then review different methods that have been used to solve the total alkalinity-pH equation, with a main focus on biogeochemical models. The shortcomings and limitations of these methods are made out and discussed. We then present two variants of a new, robust and universally convergent algorithm to solve the total alkalinity-pH equation. This algorithm does not require any a priori knowledge of the solution. SolveSAPHE (Solver Suite for Alkalinity-PH Equations) provides reference implementations of several variants of the new algorithm in Fortran 90, together with new implementations of other, previously published solvers. The new iterative procedure is shown to converge from any starting value to the physical solution. The extra computational cost for the convergence security is only 10-15% compared to the fastest algorithm in our test series.
Massive fungal biodiversity data re-annotation with multi-level clustering
DEFF Research Database (Denmark)
Vu, D.; Szoke, S.; Wiwie, Christian
2014-01-01
identification of large groups of sequences sharing common traits. Hence, there is a need for clustering tools for automatic knowledge extraction enabling the curation of large-scale databases. Current sophisticated approaches on sequence clustering are based on pairwise similarity matrices. This is impractical...... for databases of hundreds of thousands of sequences as such a similarity matrix alone would exceed the available memory. In this paper, a new approach called MultiLevel Clustering (MLC) is proposed which avoids a majority of sequence comparisons, and therefore, significantly reduces the total runtime...
A Guide to Visual Multi-Level Interface Design From Synthesis of Empirical Study Evidence
Lam, Heidi
2010-01-01
Displaying multiple levels of data visually has been proposed to address the challenge of limited screen space. Although many previous empirical studies have addressed different aspects of this question, the information visualization research community does not currently have a clearly articulated consensus on how, when, or even if displaying data at multiple levels is effective. To shed more light on this complex topic, we conducted a systematic review of 22 existing multi-level interface studies to extract high-level design guidelines. To facilitate discussion, we cast our analysis findings
Multi-level adaptive simulation of transient two-phase flow in heterogeneous porous media
Chueh, C.C.
2010-10-01
An implicit pressure and explicit saturation (IMPES) finite element method (FEM) incorporating a multi-level shock-type adaptive refinement technique is presented and applied to investigate transient two-phase flow in porous media. Local adaptive mesh refinement is implemented seamlessly with state-of-the-art artificial diffusion stabilization allowing simulations that achieve both high resolution and high accuracy. Two benchmark problems, modelling a single crack and a random porous medium, are used to demonstrate the robustness of the method and illustrate the capabilities of the adaptive refinement technique in resolving the saturation field and the complex interaction (transport phenomena) between two fluids in heterogeneous media. © 2010 Elsevier Ltd.
A longitudinal, multi-level comparative study of quality and safety in European hospitals
DEFF Research Database (Denmark)
Robert, Glenn B; Anderson, Janet E; Burnett, Susan J
2011-01-01
these impact on the quality of health care; the findings will be designed to help policy makers, payers and hospital managers understand the factors and processes that enable hospitals in Europe to achieve-and sustain-high quality services for their patients. METHODS/DESIGN: in-depth multi-level (macro, meso...... and micro-system) analysis of healthcare quality policies and practices in 5 European countries, including longitudinal case studies in a purposive sample of 10 hospitals. The project design has three major features: • a working definition of quality comprising three components: clinical effectiveness...
Critical network effect induces business oscillations in multi-level marketing systems
Juanico, Dranreb Earl
2012-01-01
The "social-networking revolution" of late (e.g., with the advent of social media, Facebook, and the like) has been propelling the crusade to elucidate the embedded networks that underlie economic activity. An unexampled synthesis of network science and economics uncovers how the web of human interactions spurred by familiarity and similarity could potentially induce the ups and downs ever so common to our economy. Zeroing in on the million-strong global industry known as multi-level marketing, this study finds that such a socially-powered enterprise can only work stably through discrimination about who to make entrepreneurial connections with.
Multi-level governance-perspective on management of nuclear waste disposal. A comparative analysis
Energy Technology Data Exchange (ETDEWEB)
Brunnengraeber, Achim; Haefner, Daniel
2015-07-01
The primary aim of the project is to conduct a detailed social and political analysis of the preconditions for the development of an acceptable strategy for nuclear waste disposal in Germany. This includes the identification of stakeholders and their interests, responsibilities, value systems, views and expectations as well as paths for a constructive approach to dialogue and problem-solving. A focus of the research project will be an international comparative multi-level governance analysis of acceptance patterns and steering mechanisms for conflict resolution.
Fabrication and characterization of injection molded multi level nano and microfluidic systems
DEFF Research Database (Denmark)
Matteucci, Marco; Christiansen, Thomas Lehrmann; Tanzi, Simone
2013-01-01
We here present a method for fabrication of multi-level all-polymer chips by means of silicon dry etching, electroplating and injection molding. This method was used for successful fabrication of microfluidic chips for applications in the fields of electrochemistry, cell trapping and DNA elongation......-treated foils and presentation of a simple model for estimating the delamination pressure. With UV surface treatments, foils of 100μm thickness were found to withstand pressures up to 9atm in Ø4mm cylindrical inlets when thermally bonded to micropatterned substrates of 2mm thickness....
Accelerated Multi-Level Atoms in an Electromagnetic Vacuum and Fulling-Davies-Unruh Effect
Institute of Scientific and Technical Information of China (English)
ZHU Zhi-Ying; YU Hong-Wei
2008-01-01
We consider,from the point of view of a coaccelerated frame,a uniformly accelerated multi-level atom in interaction with vacuum quantum electromagnetic fields in the multi-polar coupling scheme,and calculate the rate of change of the atom's energy assuming a thermal bath at a finite temperature T in the Rindler wedge.Comparison with the spontaneous excitation rate of the atom calculated in the instantaneous inertial frame of the atom shows that both the inertial and coaccelerated observer would agree with each other only when the temperature of the thermal bath equals the FDU value TFDV = a/2π.
A Dynamic Multi-Level Factor Model with Long-Range Dependence
DEFF Research Database (Denmark)
Ergemen, Yunus Emre; Rodríguez-Caballero, Carlos Vladimir
A dynamic multi-level factor model with stationary or nonstationary global and regional factors is proposed. In the model, persistence in global and regional common factors as well as innovations allows for the study of fractional cointegrating relationships. Estimation of global and regional...... is then applied to the Nord Pool power market for the analysis of price comovements among different regions within the power grid. We find that the global factor can be interpreted as the system price of the power grid as well as a fractional cointegration relationship between prices and the global factor....
Coherent control in strongly driven multi-level systems: quantum vs classical features
Ivanov, Misha; Bartram, David; Smirnova, Olga
2012-08-01
We look at wavepacket dynamics in multi-level systems driven by resonant two-colour fields. We show that control of this dynamics, performed by controlling the relative phase between the driving fields, can be mapped on a problem of molecular alignment and orientation on a plane. Changing the relative phase between the two colours corresponds to changing the angle between aligning and orienting fields. This map offers physically transparent qualitative and quantitative insight into the seemingly complex dynamics, including the analysis of quantum versus classical features of the two-colour coherent control.
Multi-level Expression Design Language: Requirement level (MEDL-R) system evaluation
1980-01-01
An evaluation of the Multi-Level Expression Design Language Requirements Level (MEDL-R) system was conducted to determine whether it would be of use in the Goddard Space Flight Center Code 580 software development environment. The evaluation is based upon a study of the MEDL-R concept of requirement languages, the functions performed by MEDL-R, and the MEDL-R language syntax. Recommendations are made for changes to MEDL-R that would make it useful in the Code 580 environment.
Options for future effective water management in Lombok: A multi-level nested framework
Sjah, Taslim; Baldwin, Claudia
2014-11-01
Previous research on water use in Lombok identified reduced water available in springs and limits on seasonal water availability. It foreshadowed increasing competition for water resources in critical areas of Lombok. This study examines preliminary information on local social-institutional arrangements for water allocation in the context of Ostrom's rules for self-governing institutions. We identify robust customary mechanisms for decision-making about water sharing and rules at a local level and suggest areas of further investigation for strengthening multi-level networked and nested frameworks, in collaboration with higher levels of government.
The Application of Multi-level Fuzzy Judgement in the Appraisement of Green Products
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The appraisement of "the green level" for a green p ro duct is a problem that has to deal with multi-aspect and multi-stratification. According to the property of the items that affect "the green level" of the pro duct, they can be divided into aspects, elements and factors. These make appreci able grades. The multi-level fuzzy judgement can solve the appraisement problem that considers the influences of design, manufacture, use and recovery in all- life cycle or multi-life cycle of product. In the judgin...
Design of QoS-Aware Multi-Level MAC-Layer for Wireless Body Area Network.
Hu, Long; Zhang, Yin; Feng, Dakui; Hassan, Mohammad Mehedi; Alelaiwi, Abdulhameed; Alamri, Atif
2015-12-01
With the advances in wearable computing and various wireless technologies, there is an increasing trend to outsource body signals from wireless body area network (WBAN) to outside world including cyber space, healthcare big data clouds, etc. Since the environmental and physiological data collected by multimodal sensors have different importance, the provisioning of quality of service (QoS) for the sensory data in WBAN is a critical issue. This paper proposes multiple level-based QoS design at WBAN media access control layer in terms of user level, data level and time level. In the proposed QoS provisioning scheme, different users have different priorities, various sensory data collected by different sensor nodes have different importance, while data priority for the same sensor node varies over time. The experimental results show that the proposed multi-level based QoS provisioning solution in WBAN yields better performance for meeting QoS requirements of personalized healthcare applications while achieving energy saving.
1973-07-01
COMPUTER ALGORITHMS FOR THE SOLUTION OF THE SHALLOW-FLUID EQUATIONS AS A MEANS OF COMPUTING TERRAIN INFLUENCES ON WIND FIELDS APPENDICES A, B, C AND D By...2- .A. .C-42 AD-A129 066 STUDY AND INVESTIGATION OF COMPUTER ALGORITHMS FOR THE I SOLUTION OF THE SN.. (U) CRAMER (H E) CO INC SALT LAKE CITY UT A G
多层次RFID数据流上复杂事件检测%Detection of complex event over RFID data streams with multi-levels
Institute of Scientific and Technical Information of China (English)
彭商濂; 李战怀; 李强; 陈群
2011-01-01
For the problems that exist in event detection over multi-levels of RFID （radio frequency identification） data streams, complex event processing over multi-levels （item-level, case level, pallet level） of RFID event streams were investigated. Encoding schemas between different levels of RFID objects were proposed to maintain relationship and state transfer between the encoding objects. Corresponding event detection algorithms based on encoding schemas were presented. Firstly, the event model and motivation example were illustrated. Then the encoding schemas and event detection algorithms were explained in detail. At last, extensive experiments were carried out to verify the proposed algorithms. The experimental results illustrate the soundness and effectiveness of proposed methods.%针对多粒度RFID数据流复杂事件检测存在的问题，研究多粒度RFID数据流（如物品级、箱子级、托盘级）上复杂事件检测问题．提出了不同层次目标间关系的编码方案，并在此编码基础上提出了相应的复杂事件检测算法．使用编码方法表示不同层次RFID对象的关系及状态变化．首先给出了事件模型和动机实例；然后详细阐述了编码方法和复杂事件检测算法．实验结果表明提出的方法是可行和有效的．
Design of all-optical multi-level regenerators based on Mach-Zehnder interferometer
Kong, Xiangjian; Wu, Baojian; Zhou, Xingyu; Wan, Qingyao; Jiang, Shanglong; Wen, Feng; Qiu, Kun
2016-12-01
We propose a design method for all-optical multi-level regenerators by mimicking the normalized power transfer function (PTF) in the first-order approximation to the ideal step-like PTF, in which a key step is to appropriately select the amplitude and phase conditions of Mach-Zehnder-interferometer (MZI)-based regenerators. As an example, we describe the design process of the self-phase-modulation (SPM)-based MZI regenerator constructed by a section of nonlinear fiber and an optical phase shifter (OPS). It is shown that the parameter of reference power level (RPL) can be regarded as the upper limit of input power, which is useful for the measure of the multi-level regeneration performance. The number of regenerative power levels increases with the RPL parameter. For 4-level pulse amplitude modulated (4PAM) optical signals degraded by the Gaussian noises with the standard deviation of 0.02, the SPM-based MZI regenerator has an average noise reduction ratio (NRR) of 6.5 dB, better than that of 1st-order regenerator by about 5 dB.
Agent-based model with multi-level herding for complex financial systems
Chen, Jun-Jie; Tan, Lei; Zheng, Bo
2015-02-01
In complex financial systems, the sector structure and volatility clustering are respectively important features of the spatial and temporal correlations. However, the microscopic generation mechanism of the sector structure is not yet understood. Especially, how to produce these two features in one model remains challenging. We introduce a novel interaction mechanism, i.e., the multi-level herding, in constructing an agent-based model to investigate the sector structure combined with volatility clustering. According to the previous market performance, agents trade in groups, and their herding behavior comprises the herding at stock, sector and market levels. Further, we propose methods to determine the key model parameters from historical market data, rather than from statistical fitting of the results. From the simulation, we obtain the sector structure and volatility clustering, as well as the eigenvalue distribution of the cross-correlation matrix, for the New York and Hong Kong stock exchanges. These properties are in agreement with the empirical ones. Our results quantitatively reveal that the multi-level herding is the microscopic generation mechanism of the sector structure, and provide new insight into the spatio-temporal interactions in financial systems at the microscopic level.
Multi-level perspective on high-order harmonic generation in solids
Wu, Mengxi; Gaarde, Mette B
2016-01-01
We investigate high-order harmonic generation in a solid, modeled as a multi-level system dressed by a strong infrared laser field. We show that the cutoff energies and the relative strengths of the multiple plateaus that emerge in the harmonic spectrum can be understood both qualitatively and quantitatively by considering a combination of adiabatic and diabatic processes driven by the strong field. Such a model was recently used to interpret the multiple plateaus exhibited in harmonic spectra generated by solid argon and krypton [Ndabashimiye {\\it et al.}, Nature 534, 520 (2016)]. We also show that when the multi-level system originates from the Bloch state at the $\\Gamma$ point of the band structure, the laser-dressed states are equivalent to the Houston states [Krieger {\\it el al.} Phys. Rev. B 33, 5494 (1986)] and will therefore map out the band structure away from the $\\Gamma$ point as the laser field increases. This leads to a semi-classical three-step picture in momentum space that describes the high-o...
Multi-level functionality of social media in the aftermath of the Great East Japan Earthquake.
Jung, Joo-Young; Moro, Munehito
2014-07-01
This study examines the multi-level functionalities of social media in the aftermath of the Great East Japan Earthquake of 11 March 2011. Based on a conceptual model of multi-level story flows of social media (Jung and Moro, 2012), the study analyses the multiple functionalities that were ascribed to social media by individuals, organisations, and macro-level social systems (government and the mass media) after the earthquake. Based on survey data, a review of Twitter timelines and secondary sources, the authors derive five functionalities of social media: interpersonal communications with others (micro level); channels for local governments; organisations and local media (meso level); channels for mass media (macro level); information sharing and gathering (cross level); and direct channels between micro-/meso- and macro-level agents. The study sheds light on the future potential of social media in disaster situations and suggests how to design an effective communication network to prepare for emergency situations. © 2014 The Author(s). Disasters © Overseas Development Institute, 2014.
Integrating Climate Projections into Multi-Level City Planning: A Texas Case Study
Hayhoe, K.; Gelca, R.; Baumer, Z.; Gold, G.
2016-12-01
Climate change impacts on energy and water are a serious concern for many cities across the United States. Regional projections from the National Assessment process, or state-specific efforts as in California and Delaware, are typically used to quantify impacts at the regional scale. However, these are often insufficient to provide information at the scale of decision-making for an individual city. Here, we describe a multi-level approach to developing and integrating usable climate information into planning, using a case study from the City of Austin in Texas, a state where few official climate resources are available. Spearheaded by the Office of Sustainability in collaboration with Austin Water, the first step was to characterize observed trends and future projections of how global climate change might affect Austin's current climate. The City then assembled a team of city experts, consulting engineers, and climate scientists to develop a methodology to assess impacts on regional hydrology as part of its Integrated Water Resource Plan, Austin's 100-year water supply and demand planning effort, an effort which included calculating a range of climate indicators and developing and evaluating a new approach to generating climate inputs - including daily streamflow and evaporation - for existing water availability models. This approach, which brings together a range of public, private, and academic experts to support a stakeholder-initiated planning effort, provides concrete insights into the critical importance of multi-level, long-term engagement for development and application of actionable climate science at the local to regional scale.
In situ multi-level analysis of viscoelastic deformation mechanisms in tendon collagen.
Gupta, H S; Seto, J; Krauss, S; Boesecke, P; Screen, H R C
2010-02-01
Tendon is a hydrated multi-level fibre composite, in which time-dependent behaviour is well established. Studies indicate significant stress relaxation, considered important for optimising tissue stiffness. However, whilst this behaviour is well documented, the mechanisms associated with the response are largely unknown. This study investigates the sub-structural mechanisms occurring during stress relaxation at both the macro (fibre) and nano (fibril) levels of the tendon hierarchy. Stress relaxation followed a two-stage exponential behaviour, during which structural changes were visible at the fibre and fibril levels. Fibril relaxation and fibre sliding showed a double exponential response, while fibre sliding was clearly the largest contributor to relaxation. The amount of stress relaxation and sub-structural reorganisation increased with increasing load increments, but fibre sliding was consistently the largest contributor to stress relaxation. A simple model of tendon viscoelasticity at the fibril and fibre levels has been developed, capturing this behaviour by serially coupling a Voigt element (collagen fibril), with two Maxwell elements (non-collagenous matrix between fibrils and fibres). This multi-level analysis provides a first step towards understanding how sub-structural interactions contribute to viscoelastic behaviour. It indicates that nano- and micro-scale shearing are significant dissipative mechanisms, and the kinetics of relaxation follows a two-stage exponential decay, well fitted by serially coupled viscoelastic elements.
Cross-Ontology multi-level association rule mining in the Gene Ontology.
Directory of Open Access Journals (Sweden)
Prashanti Manda
Full Text Available The Gene Ontology (GO has become the internationally accepted standard for representing function, process, and location aspects of gene products. The wealth of GO annotation data provides a valuable source of implicit knowledge of relationships among these aspects. We describe a new method for association rule mining to discover implicit co-occurrence relationships across the GO sub-ontologies at multiple levels of abstraction. Prior work on association rule mining in the GO has concentrated on mining knowledge at a single level of abstraction and/or between terms from the same sub-ontology. We have developed a bottom-up generalization procedure called Cross-Ontology Data Mining-Level by Level (COLL that takes into account the structure and semantics of the GO, generates generalized transactions from annotation data and mines interesting multi-level cross-ontology association rules. We applied our method on publicly available chicken and mouse GO annotation datasets and mined 5368 and 3959 multi-level cross ontology rules from the two datasets respectively. We show that our approach discovers more and higher quality association rules from the GO as evaluated by biologists in comparison to previously published methods. Biologically interesting rules discovered by our method reveal unknown and surprising knowledge about co-occurring GO terms.
Agent-based model with multi-level herding for complex financial systems.
Chen, Jun-Jie; Tan, Lei; Zheng, Bo
2015-02-11
In complex financial systems, the sector structure and volatility clustering are respectively important features of the spatial and temporal correlations. However, the microscopic generation mechanism of the sector structure is not yet understood. Especially, how to produce these two features in one model remains challenging. We introduce a novel interaction mechanism, i.e., the multi-level herding, in constructing an agent-based model to investigate the sector structure combined with volatility clustering. According to the previous market performance, agents trade in groups, and their herding behavior comprises the herding at stock, sector and market levels. Further, we propose methods to determine the key model parameters from historical market data, rather than from statistical fitting of the results. From the simulation, we obtain the sector structure and volatility clustering, as well as the eigenvalue distribution of the cross-correlation matrix, for the New York and Hong Kong stock exchanges. These properties are in agreement with the empirical ones. Our results quantitatively reveal that the multi-level herding is the microscopic generation mechanism of the sector structure, and provide new insight into the spatio-temporal interactions in financial systems at the microscopic level.
Vantamay, Somphol
2009-03-01
This study investigates factors affecting alcohol consumption among university students through a social ecological approach as a theoretical framework. A multistage sampling technique was used to select 1,200 university students in Bangkok, Thailand. Data were collected by a self-administered questionnaire. Descriptive statistics and multiple regression analysis at the 0.05 level of statistical significance were used to analyze the data. The results showed that all 22 independent variables can copredict alcohol consumption among university students at 41.2% (Adjusted = 40.1%). However, there were only 13 variables that affected alcohol consumption significantly: gender, age, monthly income, living arrangement, attitude toward alcohol use, perceived susceptibility of alcohol use, perceived self-efficacy, peer drinking, relatives drinking, accessibility of alcohol around university, accessibility of alcohol around community, exposure to anti-alcohol campaign, and exposure to alcohol advertising. The findings suggested that alcohol consumption was not only affected by the individual-level factor, but it was also affected by multi-level environmental factors, including interpersonal-level, institutional-level, community-level, and societal-level factors. Consequently, multi-level preventions should be urgently considered to prevent alcohol use among university students in Thailand.
Castrillon, Julio
2015-11-10
We develop a multi-level restricted Gaussian maximum likelihood method for estimating the covariance function parameters and computing the best unbiased predictor. Our approach produces a new set of multi-level contrasts where the deterministic parameters of the model are filtered out thus enabling the estimation of the covariance parameters to be decoupled from the deterministic component. Moreover, the multi-level covariance matrix of the contrasts exhibit fast decay that is dependent on the smoothness of the covariance function. Due to the fast decay of the multi-level covariance matrix coefficients only a small set is computed with a level dependent criterion. We demonstrate our approach on problems of up to 512,000 observations with a Matérn covariance function and highly irregular placements of the observations. In addition, these problems are numerically unstable and hard to solve with traditional methods.
Directory of Open Access Journals (Sweden)
Maria de Hoyos Guajardo, Ph.D. Candidate, M.Sc., B.Eng.
2004-11-01
Full Text Available The theory that is presented below aims to conceptualise how a group of undergraduate students tackle non-routine mathematical problems during a problem-solving course. The aim of the course is to allow students to experience mathematics as a creative process and to reflect on their own experience. During the course, students are required to produce a written ‘rubric’ of their work, i.e., to document their thoughts as they occur as well as their emotionsduring the process. These ‘rubrics’ were used as the main source of data.Students’ problem-solving processes can be explained as a three-stage process that has been called ‘solutioning’. This process is presented in the six sections below. The first three refer to a common area of concern that can be called‘generating knowledge’. In this way, generating knowledge also includes issues related to ‘key ideas’ and ‘gaining understanding’. The third and the fourth sections refer to ‘generating’ and ‘validating a solution’, respectively. Finally, once solutions are generated and validated, students usually try to improve them further before presenting them as final results. Thus, the last section deals with‘improving a solution’. Although not all students go through all of the stages, it may be said that ‘solutioning’ considers students’ main concerns as they tackle non-routine mathematical problems.
Nouizi, F.; Erkol, H.; Luk, A.; Marks, M.; Unlu, M. B.; Gulsen, G.
2016-10-01
We previously introduced photo-magnetic imaging (PMI), an imaging technique that illuminates the medium under investigation with near-infrared light and measures the induced temperature increase using magnetic resonance thermometry (MRT). Using a multiphysics solver combining photon migration and heat diffusion, PMI models the spatiotemporal distribution of temperature variation and recovers high resolution optical absorption images using these temperature maps. In this paper, we present a new fast non-iterative reconstruction algorithm for PMI. This new algorithm uses analytic methods during the resolution of the forward problem and the assembly of the sensitivity matrix. We validate our new analytic-based algorithm with the first generation finite element method (FEM) based reconstruction algorithm previously developed by our team. The validation is performed using, first synthetic data and afterwards, real MRT measured temperature maps. Our new method accelerates the reconstruction process 30-fold when compared to a single iteration of the FEM-based algorithm.
Walker, Joel W
2014-01-01
The MT2 or "s-transverse mass", statistic was developed to cope with the difficulty of associating a parent mass scale with a missing transverse energy signature, given that models of new physics generally predict production of escaping particles in pairs, while collider experiments are sensitive to just a single vector sum over all sources of missing transverse momentum. This document focuses on the generalized extension of that statistic to asymmetric one- and two-step decay chains, with arbitrary child particle masses and upstream missing transverse momentum. It provides a unified theoretical formulation, complete solution classification, taxonomy of critical points, and technical algorithmic prescription for treatment of the MT2 event scale. An implementation of the described algorithm is available for download, and is also a deployable component of the author's fully-featured selection cut software package AEACuS (Algorithmic Event Arbiter and Cut Selector).
Rowe, Arthur J.; Jones, S. W.; Thomas, D.; Harding, Stephen E.
1989-11-01
The equilibrium distribution of particles dispersed in an aqueous solute situated in a centrifugal accelerative field is routinely studied by means of an optical trace recorded photographically. Rayleigh interferometric fringe patterns have been widely used to give this trace, in which the displacement of the parallel fringes is directly related to particle concentration differences. We have developed a simple but highly efficient frameshift algorithm for automatic interpretation of these patternsl . Results obtained from extensive use and further definition of this algorithm confirm its validity and utility. We have also studied algorithms for the interpretation of Fresnel fringe patterns yielded by an alternative optical system. These more complex patterns involving non parallel fringes can be analysed successfully, subject to certain conditions, with a precision similar to that obtained using Rayleigh interference optics.
Guturu, Parthasarathy; Dantu, Ram
2008-06-01
Many graph- and set-theoretic problems, because of their tremendous application potential and theoretical appeal, have been well investigated by the researchers in complexity theory and were found to be NP-hard. Since the combinatorial complexity of these problems does not permit exhaustive searches for optimal solutions, only near-optimal solutions can be explored using either various problem-specific heuristic strategies or metaheuristic global-optimization methods, such as simulated annealing, genetic algorithms, etc. In this paper, we propose a unified evolutionary algorithm (EA) to the problems of maximum clique finding, maximum independent set, minimum vertex cover, subgraph and double subgraph isomorphism, set packing, set partitioning, and set cover. In the proposed approach, we first map these problems onto the maximum clique-finding problem (MCP), which is later solved using an evolutionary strategy. The proposed impatient EA with probabilistic tabu search (IEA-PTS) for the MCP integrates the best features of earlier successful approaches with a number of new heuristics that we developed to yield a performance that advances the state of the art in EAs for the exploration of the maximum cliques in a graph. Results of experimentation with the 37 DIMACS benchmark graphs and comparative analyses with six state-of-the-art algorithms, including two from the smaller EA community and four from the larger metaheuristics community, indicate that the IEA-PTS outperforms the EAs with respect to a Pareto-lexicographic ranking criterion and offers competitive performance on some graph instances when individually compared to the other heuristic algorithms. It has also successfully set a new benchmark on one graph instance. On another benchmark suite called Benchmarks with Hidden Optimal Solutions, IEA-PTS ranks second, after a very recent algorithm called COVER, among its peers that have experimented with this suite.
Montagnier, Olivier
2011-01-01
This study deals with the optimisation of subcritical and supercritical laminated composite drive shafts, based on a genetic algorithm. The first part focuses on the modelling of a composite drive shaft. Flexural vibrations in a simply supported composite drive shaft mounted on viscoelastic supports, including shear effects are studied. In particular, an analytic stability criterion is developed to ensure the integrity of the system. The torsional strength is then computed with the maximum stress criterion, assuming the coupling effects to be null. Torsional buckling of thin walled composite tubes is modelled using a combination between laminate theory and Fl\\"ugge theory. In the second part, the genetic algorithm is developed. The last part presents a comparative study between various composite materials solutions on a helicopter tail rotor driveline. In particular, hybrid tubes consisting of high modulus and high resistance carbon/epoxy plies are studied. These solutions make it possible to replace the conv...
Institute of Scientific and Technical Information of China (English)
宋丽娜; 王维国
2012-01-01
By constructing the iterative formula with a so-called convergence-control parameter, the generalized two-dimensional differential transform method is improved. With the enhanced technique, the nonlinear fractional Kolmogorov-Petrovskii-Piskunov equations are dealt analytically and approximate solutions are derived. The results show that the employed approach is a promising tool for solving many nonlinear fractional partial differential equations. The algorithm described in this work is expected to be employed to solve more problems in fractional calculus.
Energy Technology Data Exchange (ETDEWEB)
Toshinsky, Vladimir G.; Sekimoto, Hiroshi E-mail: hsekimot@nr.titech.ac.jp; Toshinsky, Georgy I
2000-03-01
A method to improve the optimization performance of a genetic algorithm (GA) for multiobjective optimization problems is proposed. It is based on niche induction among nondominated solutions that is fulfilled by the control on their reproduction potential by using a sharing function. It is applied to an equilibrium cycle fuel reloading pattern for a Self-Fuel-Providing Reactor, and it provides better results compared to ones obtained with an adaptation of a conventional method.
Song, Li-Na; Wang, Wei-Guo
2012-08-01
By constructing the iterative formula with a so-called convergence-control parameter, the generalized two-dimensional differential transform method is improved. With the enhanced technique, the nonlinear fractional Kolmogorov-Petrovskii-Piskunov equations are dealt analytically and approximate solutions are derived. The results show that the employed approach is a promising tool for solving many nonlinear fractional partial differential equations. The algorithm described in this work is expected to be employed to solve more problems in fractional calculus.
Energy Technology Data Exchange (ETDEWEB)
McLay, R.T.; Carey, G.F.
1996-12-31
In this study we consider parallel solution of sparse linear systems arising from discretized PDE`s. As part of our continuing work on our parallel PCG Solver package, we have made improvements in two areas. The first is improving the performance of the matrix-vector product. Here on regular finite-difference grids, we are able to use the cache memory more efficiently for smaller domains or where there are multiple degrees of freedom. The second problem of interest in the present work is the construction of preconditioners in the context of the parallel PCG solver we are developing. Here the problem is partitioned over a set of processors subdomains and the matrix-vector product for PCG is carried out in parallel for overlapping grid subblocks. For problems of scaled speedup, the actual rate of convergence of the unpreconditioned system deteriorates as the mesh is refined. Multigrid and subdomain strategies provide a logical approach to resolving the problem. We consider the parallel trade-offs between communication and computation and provide a complexity analysis of a representative algorithm. Some preliminary calculations using the parallel package and comparisons with other preconditioners are provided together with parallel performance results.
Directory of Open Access Journals (Sweden)
Motasem Aldiab
2008-01-01
Full Text Available Traditionally, the Internet provides only a “best-effort” service, treating all packets going to the same destination equally. However, providing differentiated services for different users based on their quality requirements is increasingly becoming a demanding issue. For this, routers need to have the capability to distinguish and isolate traffic belonging to different flows. This ability to determine the flow each packet belongs to is called packet classification. Technology vendors are reluctant to support algorithmic solutions for classification due to their nondeterministic performance. Although content addressable memories (CAMs are favoured by technology vendors due to their deterministic high-lookup rates, they suffer from the problems of high-power consumption and high-silicon cost. This paper provides a new algorithmic-architectural solution for packet classification that mixes CAMs with algorithms based on multilevel cutting of the classification space into smaller spaces. The provided solution utilizes the geometrical distribution of rules in the classification space. It provides the deterministic performance of CAMs, support for dynamic updates, and added flexibility for system designers.
Batistic, S.; Cerne, Matej; Vogel, Bernd
2016-01-01
The use of multi-level theories and methodologies in leadership has gained momentum in recent years. However, the leadership field still suffers from a fragmented and unclear evolution and practice of multi-level approaches. The questions of how and to what extent multi-level research has evolved in
National Research Council Canada - National Science Library
王林芳 刘加 刘小青 李明
2011-01-01
Digital mobile telecommunication systems, such as the global system for mobile （GSM） system, want to further improve speech communication quality without changing the channel encoders and decoders...
A parallel algorithm for multi-level logic synthesis using the transduction method. M.S. Thesis
Lim, Chieng-Fai
1991-01-01
The Transduction Method has been shown to be a powerful tool in the optimization of multilevel networks. Many tools such as the SYLON synthesis system (X90), (CM89), (LM90) have been developed based on this method. A parallel implementation is presented of SYLON-XTRANS (XM89) on an eight processor Encore Multimax shared memory multiprocessor. It minimizes multilevel networks consisting of simple gates through parallel pruning, gate substitution, gate merging, generalized gate substitution, and gate input reduction. This implementation, called Parallel TRANSduction (PTRANS), also uses partitioning to break large circuits up and performs inter- and intra-partition dynamic load balancing. With this, good speedups and high processor efficiencies are achievable without sacrificing the resulting circuit quality.
NSGA-Ⅱ中重复个体的控制%The Control of Overlapping Solutions in NSGA-H Algorithm
Institute of Scientific and Technical Information of China (English)
王广博; 韩庆; 钟小平
2011-01-01
The introduction of elitism strategy of NSGA-II, which can help preventing the loss of good solutions by choosing the best solutions from the merged population that merges the current population and the offspring population to construct the next population, enables easier production of overlapping individuals. The existence of overlapping individuals in the evolution populations means overlapping regions in the searching space, which makes the algorithm much less efficiently in exploiting new feasible region. In consideration of computational complexity and strengthen effectively of solution set. A remove strategy is presented to improve the NSGA-II algorithm. The numerical examples demonstrate that eliminating overlapping solutions make the NSGA-II algorithm more steady and gain a solution set with better distribution.%由于NSGA-Ⅱ引入了精英策略,为保留父代中优秀个体直接进入子代,在每一代将父代和子代所有个体混合后再选择新种群,所以在新种群中很容易产生重复个体.而进化种群中出现重复个体意味着搜索区域的重叠,使得算法探索新可行区域的效率降低.考虑到计算复杂度和增强解集的有效性,提出了一种删除策略对NSGA-Ⅱ算法进行了改进.算例表明该改进算法能获得分布更加均匀的解集,且具有更强的稳定性.
Multi-level and Multi-component Bitmap Encoding for Efficient Search Operations
Directory of Open Access Journals (Sweden)
Madhu BHAN, Department of Computer Applications
2012-12-01
Full Text Available The growing interest in data warehousing for decision makers is becoming more and more crucial to make faster and efficient decisions. On-line decision needs short response times. Many indexing techniques have been created to achieve this goal in read only environments. Indexing technique that has attracted attention in multidimensional databases is Bitmap Indexing. The paper discusses the various existing bitmap indexing techniques along with their performance characteristics. The paper proposes two new bitmap indexing techniques in the class of multi-level and multi-component encoding schemes and prove that the two techniques have better space–time performance than some of the existing techniques used for range queries. We provide an analytical model for comparing the performance of our proposed encoding schemes with that of the existing ones.
RH 1.5D: Polarized multi-level radiative transfer with partial frequency distribution
Pereira, Tiago M. D.; Uitenbroek, Han
2015-02-01
RH 1.5D performs Zeeman multi-level non-local thermodynamical equilibrium calculations with partial frequency redistribution for an arbitrary amount of chemical species. Derived from the RH code and written in C, it calculates spectra from 3D, 2D or 1D atmospheric models on a column-by-column basis (or 1.5D). It includes optimization features to speed up or improve convergence, which are particularly useful in dynamic models of chromospheres. While one should be aware of its limitations, the calculation of spectra using the 1.5D or column-by-column is a good approximation in many cases, and generally allows for faster convergence and more flexible methods of improving convergence. RH 1.5D scales well to at least tens of thousands of CPU cores.
Mapping and navigating transitions - The multi-level perspective compared with arenas of development
DEFF Research Database (Denmark)
Jørgensen, Ulrik
2012-01-01
Transitions of socio-technical systems imply the reconfiguration of institutions and politics making made evident the need to understand and intervene in existing patterns of growth and socio-technical practices in more sustainable directions. In recent decades, theories of transitions have been ...... that support sustainable transitions. (C) 2012 Elsevier B.V. All rights reserved.......Transitions of socio-technical systems imply the reconfiguration of institutions and politics making made evident the need to understand and intervene in existing patterns of growth and socio-technical practices in more sustainable directions. In recent decades, theories of transitions have been...... introduced, which include the multi-level approach indicating ways to govern transitions through understanding the interactions between niches, regimes and landscapes. An alternative approach is suggested, which takes its outset in arenas of development and increased awareness of actors and their way...
Entanglement and non-Markovianity of a multi-level atom decaying in a cavity
Zi-Long, Fan; Yu-Kun, Ren; Hao-Sheng, Zeng
2016-01-01
We present a paradigmatic method for exactly studying non-Markovian dynamics of a multi-level V-type atom interacting with a zero-temperature bosonic bath. Special attention is paid to the entanglement evolution and the dynamical non-Markovianity of a three-level V-type atom. We find that the entanglement negativity decays faster and non-Markovianity is smaller in the resonance regions than those in the non-resonance regions. More importantly, the quantum interference between the dynamical non-Markovianities induced by different transition channels is manifested, and the frequency domains for constructive and destructive interferences are found. Project supported by the National Natural Science Foundation of China (Grant Nos. 11275064 and 11075050), the Specialized Research Fund for the Doctoral Program of Higher Education, China (Grant No. 20124306110003), and the Construct Program of the National Key Discipline, China.
Multi-level segment analysis: definition and application in turbulent systems
Wang, L. P.; Huang, Y. X.
2015-06-01
For many complex systems the interaction of different scales is among the most interesting and challenging features. It seems not very successful to extract the physical properties in different scale regimes by the existing approaches, such as the structure-function and Fourier spectrum method. Fundamentally, these methods have their respective limitations, for instance scale mixing, i.e. the so-called infrared and ultraviolet effects. To make improvements in this regard, a new method, multi-level segment analysis (MSA) based on the local extrema statistics, has been developed. Benchmark (fractional Brownian motion) verifications and the important case tests (Lagrangian and two-dimensional turbulence) show that MSA can successfully reveal different scaling regimes which have remained quite controversial in turbulence research. In general the MSA method proposed here can be applied to different dynamic systems in which the concepts of multiscale and multifractality are relevant.
The Multi-level Recovery of Main-memory Real-time Database Systems with ECBH
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
Storing the whole database in the main-memory is a common method to process real-time transaction in real-time database systems. The recovery mechanism of Main-memory Real-time Database Systems (MMRTDBS) should reflect the characteristics of the main-memory database and real-time database because their structures are quite different from other conventional database systems. In this paper, therefore, we propose a multi-level recovery mechanism for main-memory real-time database systems with Extendible Chained Bucket Hashing (ECBH). Owing to the occurrence of real-time data in real-time systems, we should also consider it in our recovery mechanism. According to our performance test, this mechanism can improve the transaction concurrency, reducing transactions' deadline missing rate.
Analyzing the Role of Multi-level Learning in Implementing computerized HIS in Developing Countries
DEFF Research Database (Denmark)
Mengiste, Shegaw Anagaw
2008-01-01
and implementation of computerised HIS in Ethiopia, the paper analyses the learning mechanisms, learning outcomes and obstacles for learning at individual, group, and organizational levels. Empirical data on two distinct phases of software development and customization (District health Information Software (DHIS......) versions 1.3 and 2.0) are contrasted. More specifically, we tried to show the dynamics of learning and the specific learning mechanisms by analysing and contrasting the interaction between IS developers and public health care domain experts, technological capacity at individual, group, and organizational......This paper presents a perspective for looking at the development and implementation of large scale computerised HIS as a multi-level learning process. Drawing on the empirical evidences from the ongoing Health Information systems program ( HISP) initiatives on the development, customization...
Shim, Jae-Jun; Doh, Jae-Won; Yoon, Seok-Mann; Bae, Hack-Gun; Yun, Il-Gyu
2004-01-01
Acute neurologic deterioration is not a rare event in the surgical decompression for thoracic spinal stenosis. We report a case of transient paraparesis after decompressive laminectomy in a 50-yr-old male patient with multi-level thoracic ossification of the ligamentum flavum and cervical ossification of the posterior longitudinal ligament. Decompressive laminectomy from T9 to T11 was performed without gross neurological improvement. Two weeks after the first operation, laminoplasty from C4 to C6 and additional decompressive laminectomies of T3, T4, T6, and T8 were performed. Paraparesis developed 3 hr after the second operation, which recovered spontaneously 5 hr thereafter. CT and MRI were immediately performed, but there were no corresponding lesions. Vascular compromise of the borderlines of the arterial supply by microthrombi might be responsible for the paraparesis. PMID:15308861
Modelling and simulation of complex systems: an approach based on multi-level agents
Fougères, Alain-Jérôme
2012-01-01
A complex system is made up of many components with many interactions. So the design of systems such as simulation systems, cooperative systems or assistance systems includes a very accurate modelling of interactional and communicational levels. The agent-based approach provides an adapted abstraction level for this problem. After having studied the organizational context and communicative capacities of agentbased systems, to simulate the reorganization of a flexible manufacturing, to regulate an urban transport system, and to simulate an epidemic detection system, our thoughts on the interactional level were inspired by human-machine interface models, especially those in "cognitive engineering". To provide a general framework for agent-based complex systems modelling, we then proposed a scale of four behaviours that agents may adopt in their complex systems (reactive, routine, cognitive, and collective). To complete the description of multi-level agent models, which is the focus of this paper, we illustrate ...
Analyzing the Role of Multi-level Learning in Implementing computerized HIS in Developing Countries
DEFF Research Database (Denmark)
Mengiste, Shegaw Anagaw
2008-01-01
This paper presents a perspective for looking at the development and implementation of large scale computerised HIS as a multi-level learning process. Drawing on the empirical evidences from the ongoing Health Information systems program ( HISP) initiatives on the development, customization...... and implementation of computerised HIS in Ethiopia, the paper analyses the learning mechanisms, learning outcomes and obstacles for learning at individual, group, and organizational levels. Empirical data on two distinct phases of software development and customization (District health Information Software (DHIS......) versions 1.3 and 2.0) are contrasted. More specifically, we tried to show the dynamics of learning and the specific learning mechanisms by analysing and contrasting the interaction between IS developers and public health care domain experts, technological capacity at individual, group, and organizational...
Lee, G; Yoo, J H; Lee, Geunbae; Lee, Jong-Hyeok; Yoo, JinHee
1996-01-01
Most of the post-processing methods for character recognition rely on contextual information of character and word-fragment levels. However, due to linguistic characteristics of Korean, such low-level information alone is not sufficient for high-quality character-recognition applications, and we need much higher-level contextual information to improve the recognition results. This paper presents a domain independent post-processing technique that utilizes multi-level morphological, syntactic, and semantic information as well as character-level information. The proposed post-processing system performs three-level processing: candidate character-set selection, candidate eojeol (Korean word) generation through morphological analysis, and final single eojeol-sequence selection by linguistic evaluation. All the required linguistic information and probabilities are automatically acquired from a statistical corpus analysis. Experimental results demonstrate the effectiveness of our method, yielding error correction r...
Planarization for three-dimensional photonic crystals and other multi-level nanoscale structures.
Subramania, G
2007-01-24
We describe an approach for achieving local as well as global planarization in the fabrication of multi-level nanoscale structures. Using a 'pre-fill-in' technique, where trenches are filled with SiO(2) prior to the application of a planarizing liquid, we demonstrate that the global degree of planarization can be improved from a mere approximately 25% to over approximately 90%. The first layer of a woodpile photonic lattice with a period of approximately 0.5 microm and a minimum feature size of approximately 0.2 microm is used as an example structure to illustrate the issues involved in planarization. This method provides an attractive and simpler alternative to the traditional chemical mechanical polishing approach, which can be quite complicated at nanoscale features involving non-traditional materials.
Multi-level annotation of the specialized Corpus of Dialogs of Disabled Polish Speakers
Directory of Open Access Journals (Sweden)
Joanna Trzebińska
2014-09-01
Full Text Available Multi-level annotation of the specialized Corpus of Dialogs of Disabled Polish Speakers While Polish language is relatively well represented in general purpose corpora such as National Polish Language Corpus still there are groups of speakers that are underrepresented in reference corpora. One of such sub-groups is the disabled people community. On the other hand there is a growing need for understanding how disability influences social and cognitive abilities, language in particular. In this paper, we present a specialized Corpus of Dialogs of Disabled Speakers. The process of compiling, transcription and annotation of pragmatic, semantic and morphosyntactic features will be described, as well as Corpus applications will be discussed.
Multi-Level, Multi-Component Approaches to Community Based Interventions for Healthy Living
DEFF Research Database (Denmark)
Mikkelsen, Bent Egberg; Novotny, Rachel; Gittelsohn, Joel
2016-01-01
There is increasing interest in integrated and coordinated programs that intervene in multiple community settings/institutions at the same time and involve policy and system changes. The purpose of the paper is to analyse three comparable cases of Multi Level, Multi Component intervention programs...... the potential of ML-MC community-based public health nutrition interventions to create sustainable change. The paper proposes methodology, guidelines and directions for future research through analysis and examination strengths and weaknesses in the programs. Similarities are that they engage and commit local...... stakeholders in a structured approach to integrate intervention components in order to create dose and intensity. In that way, they all make provisions for post intervention impact sustainability. All programs target the child and family members' knowledge, attitudes, behavior, the policy level...
Multi-level segment analysis: definition and application in turbulent systems
Wang, L P
2015-01-01
For many complex systems the interaction of different scales is among the most interesting and challenging features. It seems not very successful to extract the physical properties in different scale regimes by the existing approaches, such as structure-function and Fourier spectrum method. Fundamentally these methods have their respective limitations, for instance scale mixing, i.e. the so-called infrared and ultraviolet effects. To make improvement in this regard, a new method, multi-level segment analysis (MSA) based on the local extrema statistics, has been developed. Benchmark (fractional Brownian motion) verifications and the important case tests (Lagrangian and two-dimensional turbulence) show that MSA can successfully reveal different scaling regimes, which has been remaining quite controversial in turbulence research. In general the MSA method proposed here can be applied to different dynamic systems in which the concepts of multiscaling and multifractal are relevant.
The Application of Multi-level Fuzzy Judgement in the Appraisement of Green Products
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The appraisement of "the green level" fora green product is a problem that has to deal with multi-aspects and multi-stratification. According to the property of the items that affect "the green level" of the product, they can be divided into aspects, elements and factors. These make appreciable grades. Multi-level fuzzy judgement can solve the appraisement problem that considers the influences of design, manufacture, use and recovery in all-life cycle or multi-life cycle of a product. In the judging process it not only deals with the action of all factors, but also continues to have all messages in grade judgement. The power coefficients stand out as the main items. An example is given to show the judgement process.
An Automatic Optic Disk Detection and Segmentation System using Multi-level Thresholding
Directory of Open Access Journals (Sweden)
KARASULU, B.
2014-05-01
Full Text Available Optic disk (OD boundary localization is a substantial problem in ophthalmic image processing research area. In order to segment the region of OD, we developed an automatic system which involves a multi-level thresholding. The OD segmentation results of the system in terms of average precision, recall and accuracy for DRIVE database are 98.88%, 99.91%, 98.83%, for STARE database are 98.62%, 97.38%, 96.11%, and for DIARETDB1 database are 99.29%, 99.90%, 99.20%, respectively. The experimental results show that our system works properly on retinal image databases with diseased retinas, diabetic signs, and a large degree of quality variability.
Directory of Open Access Journals (Sweden)
Hedong Xu
2014-01-01
Full Text Available The reconstruction of destroyed paper documents is of more interest during the last years. This topic is relevant to the fields of forensics, investigative sciences, and archeology. Previous research and analysis on the reconstruction of cross-cut shredded text document (RCCSTD are mainly based on the likelihood and the traditional heuristic algorithm. In this paper, a feature-matching algorithm based on the character recognition via establishing the database of the letters is presented, reconstructing the shredded document by row clustering, intrarow splicing, and interrow splicing. Row clustering is executed through the clustering algorithm according to the clustering vectors of the fragments. Intrarow splicing regarded as the travelling salesman problem is solved by the improved genetic algorithm. Finally, the document is reconstructed by the interrow splicing according to the line spacing and the proximity of the fragments. Computational experiments suggest that the presented algorithm is of high precision and efficiency, and that the algorithm may be useful for the different size of cross-cut shredded text document.
Directory of Open Access Journals (Sweden)
Chunhua Ju
2012-01-01
Full Text Available Managing multiple project is a complex task involving the unrelenting pressures of time and cost. Many studies have proposed various tools and techniques for single-project scheduling; however, the literature further considering multimode or multiproject issues occurring in the real world is rather scarce. In this paper, design structure matrix (DSM and an improved artificial immune network algorithm (aiNet are developed to solve a multi-mode resource-constrained scheduling problem. Firstly, the DSM is used to simplify the mathematic model of multi-project scheduling problem. Subsequently, aiNet algorithm comprised of clonal selection, negative selection, and network suppression is adopted to realize the local searching and global searching, which will assure that it has a powerful searching ability and also avoids the possible combinatorial explosion. Finally, the approach is tested on a set of randomly cases generated from ProGen. The computational results validate the effectiveness of the proposed algorithm comparing with other famous metaheuristic algorithms such as genetic algorithm (GA, simulated annealing algorithm (SA, and ant colony optimization (ACO.
Building a traceable climate model hierarchy with multi-level emulators
Tran, Giang T.; Oliver, Kevin I. C.; Sóbester, András; Toal, David J. J.; Holden, Philip B.; Marsh, Robert; Challenor, Peter; Edwards, Neil R.
2016-04-01
To study climate change on multi-millennial timescales or to explore a model's parameter space, efficient models with simplified and parameterised processes are required. However, the reduction in explicitly modelled processes can lead to underestimation of some atmospheric responses that are essential to the understanding of the climate system. While more complex general circulations are available and capable of simulating a more realistic climate, they are too computationally intensive for these purposes. In this work, we propose a multi-level Gaussian emulation technique to efficiently estimate the outputs of steady-state simulations of an expensive atmospheric model in response to changes in boundary forcing. The link between a computationally expensive atmospheric model, PLASIM (Planet Simulator), and a cheaper model, EMBM (energy-moisture balance model), is established through the common boundary condition specified by an ocean model, allowing for information to be propagated from one to the other. This technique allows PLASIM emulators to be built at a low cost. The method is first demonstrated by emulating a scalar summary quantity, the global mean surface air temperature. It is then employed to emulate the dimensionally reduced 2-D surface air temperature field. Even though the two atmospheric models chosen are structurally unrelated, Gaussian process emulators of PLASIM atmospheric variables are successfully constructed using EMBM as a fast approximation. With the extra information gained from the cheap model, the multi-level emulator of PLASIM's 2-D surface air temperature field is built using only one-third the amount of expensive data required by the normal single-level technique. The constructed emulator is shown to capture 93.2 % of the variance across the validation ensemble, with the averaged RMSE of 1.33 °C. Using the method proposed, quantities from PLASIM can be constructed and used to study the effects introduced by PLASIM's atmosphere.
Multi-level bootstrap analysis of stable clusters in resting-state fMRI.
Bellec, Pierre; Rosa-Neto, Pedro; Lyttelton, Oliver C; Benali, Habib; Evans, Alan C
2010-07-01
A variety of methods have been developed to identify brain networks with spontaneous, coherent activity in resting-state functional magnetic resonance imaging (fMRI). We propose here a generic statistical framework to quantify the stability of such resting-state networks (RSNs), which was implemented with k-means clustering. The core of the method consists in bootstrapping the available datasets to replicate the clustering process a large number of times and quantify the stable features across all replications. This bootstrap analysis of stable clusters (BASC) has several benefits: (1) it can be implemented in a multi-level fashion to investigate stable RSNs at the level of individual subjects and at the level of a group; (2) it provides a principled measure of RSN stability; and (3) the maximization of the stability measure can be used as a natural criterion to select the number of RSNs. A simulation study validated the good performance of the multi-level BASC on purely synthetic data. Stable networks were also derived from a real resting-state study for 43 subjects. At the group level, seven RSNs were identified which exhibited a good agreement with the previous findings from the literature. The comparison between the individual and group-level stability maps demonstrated the capacity of BASC to establish successful correspondences between these two levels of analysis and at the same time retain some interesting subject-specific characteristics, e.g. the specific involvement of subcortical regions in the visual and fronto-parietal networks for some subjects.
Post-stroke balance rehabilitation under multi-level electrotherapy: a conceptual review
Directory of Open Access Journals (Sweden)
Anirban eDutta
2014-12-01
Full Text Available Stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to respond to intrinsic or extrinsic stimuli by reorganizing its structure, function and connections is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. It has been shown that active cortical participation in a closed-loop brain machine interface (BMI can induce neuroplasticity in cortical networks where the brain acts as a controller, e.g., during a visuomotor task. Here, the motor task can be assisted with neuromuscular electrical stimulation (NMES where the BMI will act as a real-time decoder. However, the cortical control and induction of neuroplasticity in a closed-loop brain machine interface is also dependent on the state of brain, e.g., visuospatial attention during visuomotor task performance. In fact, spatial neglect is a hidden disability that is a common complication of stroke and is associated with prolonged hospital stays, accidents, falls, safety problems and chronic functional disability. This hypothesis and theory article presents a multi-level electrotherapy paradigm towards motor rehabilitation in virtual reality that postulates that while the brain acts as a controller in a closed-loop BMI to drive NMES, the state of brain can be can be altered towards improvement of visuomotor task performance with non-invasive brain stimulation. This leads to a multi-level electrotherapy paradigm where a virtual reality-based adaptive response technology is proposed for post-stroke balance rehabilitation. In this article, we present a conceptual review of the related
Wang, S; Huang, G H; Zhou, Y
2016-05-01
In this study, a multi-level factorial-vertex fuzzy-stochastic programming (MFFP) approach is developed for optimization of water resources systems under probabilistic and possibilistic uncertainties. MFFP is capable of tackling fuzzy parameters at various combinations of α-cut levels, reflecting distinct attitudes of decision makers towards fuzzy parameters in the fuzzy discretization process based on the α-cut concept. The potential interactions among fuzzy parameters can be explored through a multi-level factorial analysis. A water resources management problem with fuzzy and random features is used to demonstrate the applicability of the proposed methodology. The results indicate that useful solutions can be obtained for the optimal allocation of water resources under fuzziness and randomness. They can help decision makers to identify desired water allocation schemes with maximized total net benefits. A variety of decision alternatives can also be generated under different scenarios of water management policies. The findings from the factorial experiment reveal the interactions among design factors (fuzzy parameters) and their curvature effects on the total net benefit, which are helpful in uncovering the valuable information hidden beneath the parameter interactions affecting system performance. A comparison between MFFP and the vertex method is also conducted to demonstrate the merits of the proposed methodology.
Karimaghaloo, Zahra; Arnold, Douglas L; Arbel, Tal
2016-01-01
Detection and segmentation of large structures in an image or within a region of interest have received great attention in the medical image processing domains. However, the problem of small pathology detection and segmentation still remains an unresolved challenge due to the small size of these pathologies, their low contrast and variable position, shape and texture. In many contexts, early detection of these pathologies is critical in diagnosis and assessing the outcome of treatment. In this paper, we propose a probabilistic Adaptive Multi-level Conditional Random Fields (AMCRF) with the incorporation of higher order cliques for detecting and segmenting such pathologies. In the first level of our graphical model, a voxel-based CRF is used to identify candidate lesions. In the second level, in order to further remove falsely detected regions, a new CRF is developed that incorporates higher order textural features, which are invariant to rotation and local intensity distortions. At this level, higher order textures are considered together with the voxel-wise cliques to refine boundaries and is therefore adaptive. The proposed algorithm is tested in the context of detecting enhancing Multiple Sclerosis (MS) lesions in brain MRI, where the problem is further complicated as many of the enhancing voxels are associated with normal structures (i.e. blood vessels) or noise in the MRI. The algorithm is trained and tested on large multi-center clinical trials from Relapsing-Remitting MS patients. The effect of several different parameter learning and inference techniques is further investigated. When tested on 120 cases, the proposed method reaches a lesion detection rate of 90%, with very few false positive lesion counts on average, ranging from 0.17 for very small (3-5 voxels) to 0 for very large (50+ voxels) regions. The proposed model is further tested on a very large clinical trial containing 2770 scans where a high sensitivity of 91% with an average false positive
Maimoun, Mousa; Madani, Kaveh; Reinhart, Debra
2016-04-15
Historically, the U.S. waste collection fleet was dominated by diesel-fueled waste collection vehicles (WCVs); the growing need for sustainable waste collection has urged decision makers to incorporate economically efficient alternative fuels, while mitigating environmental impacts. The pros and cons of alternative fuels complicate the decisions making process, calling for a comprehensive study that assesses the multiple factors involved. Multi-criteria decision analysis (MCDA) methods allow decision makers to select the best alternatives with respect to selection criteria. In this study, two MCDA methods, Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Simple Additive Weighting (SAW), were used to rank fuel alternatives for the U.S. waste collection industry with respect to a multi-level environmental and financial decision matrix. The environmental criteria consisted of life-cycle emissions, tail-pipe emissions, water footprint (WFP), and power density, while the financial criteria comprised of vehicle cost, fuel price, fuel price stability, and fueling station availability. The overall analysis showed that conventional diesel is still the best option, followed by hydraulic-hybrid WCVs, landfill gas (LFG) sourced natural gas, fossil natural gas, and biodiesel. The elimination of the WFP and power density criteria from the environmental criteria ranked biodiesel 100 (BD100) as an environmentally better alternative compared to other fossil fuels (diesel and natural gas). This result showed that considering the WFP and power density as environmental criteria can make a difference in the decision process. The elimination of the fueling station and fuel price stability criteria from the decision matrix ranked fossil natural gas second after LFG-sourced natural gas. This scenario was found to represent the status quo of the waste collection industry. A sensitivity analysis for the status quo scenario showed the overall ranking of diesel and
Institute of Scientific and Technical Information of China (English)
王赟松; 刘钦龙; 高卫中
2004-01-01
标准BP神经网络算法收敛速度慢是限制其广泛应用的主要原因.为此,以标准BP算法为基础,应用最小二乘法理论,提出了一种收敛速度快的BP算法--NLMSBP算法.仿真结果表明,和标准BP算法及其它改进形式比较,NLMSBP算法收敛速度大大提高,稳定性并未降低,这为BP神经网络应用于实时性要求高的场合提供了算法基础.该算法缺点是计算量大,所需计算机内存大,不适于大型网络的计算.%That standard backpropagation(BP) algorithm for training neural networks converges slowly is the main reason why it cannot be used widely in practical applications. Therefore, a new kind of BP algorithm, called the NLMSBP algorithm for short, is put forward in this paper by using solutions for a nonlinear least mean square problem. The experimental results have proved that the algorithm converges very fast and has good stability compared with the standard BP algorithm and the other modifications. It is suitable for training the network with a few thousands of weights and offsets and high training precision demand. If the computer memory is enough, the superiority of the algorithm over the others is very notable. Indeed, it is worth popularizing.
Directory of Open Access Journals (Sweden)
Nasri Abdelfatah
2011-01-01
Full Text Available The Reactive power flow’s is one of the most electrical distribution systems problem wich have great of interset of the electrical network researchers, it’s cause’s active power transmission reduction, power losses decreasing, and the drop voltage’s increase. In this research we described the efficiency of the FLC-GAO approach to solve the optimal power flow (OPF combinatorial problem. The proposed approach employ tow algorithms, Fuzzy logic controller (FLC algorithm for critical nodal detection and gentic algorithm optimization (GAO algorithm for optimal seizing capacitor.GAO method is more efficient in combinatory problem solutions. The proposed approach has been examined and tested on the standard IEEE 57-bus the resulats show the power loss minimization denhancement, voltage profile, and stability improvement. The proposed approach results have been compared to those that reported in the literature recently. The results are promising and show the effectiveness and robustness of the proposed approach.
Barriers to Uptake of Conservation Agriculture in southern Africa: Multi-level Analyses from Malawi
Dougill, Andrew; Stringer, Lindsay; Whitfield, Stephen; Wood, Ben; Chinseu, Edna
2015-04-01
Conservation agriculture is a key set of actions within the growing body of climate-smart agriculture activities being advocated and rolled out across much of the developing world. Conservation agriculture has purported benefits for environmental quality, food security and the sustained delivery of ecosystem services. In this paper, new multi-level analyses are presented, assessing the current barriers to adoption of conservation agriculture practices in Malawi. Despite significant donor initiatives that have targeted conservation agriculture projects, uptake rates remain low. This paper synthesises studies from across 3 levels in Malawi: i.) national level- drawing on policy analysis, interviews and a multi-stakeholder workshop; ii.) district level - via assessments of development plans and District Office and extension service support, and; iii) local level - through data gained during community / household level studies in Dedza District that have gained significant donor support for conservation agriculture as a component of climate smart agriculture initiatives. The national level multi-stakeholder Conservation Agriculture workshop identified three areas requiring collaborative research and outlined routes for the empowerment of the National Conservation Agriculture Task Force to advance uptake of conservation agriculture and deliver associated benefits in terms of agricultural development, climate adaptation and mitigation. District level analyses highlight that whilst District Development Plans are now checked against climate change adaptation and mitigation criteria, capacity and knowledge limitations exist at the District level, preventing project interventions from being successfully up-scaled. Community level assessments highlight the need for increased community participation at the project-design phase and identify a pressing requirement for conservation agriculture planning processes (in particular those driven by investments in climate
Sabeur, Zoheir; Chakravarthy, Ajay; Bashevoy, Maxim; Modafferi, Stefano
2013-04-01
The rapid increase in environmental observations which are conducted by Small to Medium Enterprise communities and volunteers using affordable in situ sensors at various scales, in addition to the more established observatories set up by environmental and space agencies using airborne and space-borne sensing technologies is generating serious amounts of BIG data at ever increasing speeds. Furthermore, the emergence of Future Internet technologies and the urgent requirements for the deployment of specific enablers for the delivery of processed environmental knowledge in real-time with advanced situation awareness to citizens has reached paramount importance. Specifically, it has become highly critical now to build and provide services which automate the aggregation of data from various sources, while surmounting the semantic gaps, conflicts and heterogeneity in data sources. The early stage aggregation of data will enable the pre-processing of data from multiple sources while reconciling the temporal gaps in measurement time series, and aligning their respective a-synchronicities. This low level type of data fusion process needs to be automated and chained to more advanced level of data fusion services specialising in observation forecasts at spaces where sensing is not deployed; or at time slices where sensing has not taken place yet. As a result, multi-level fusion services are required among the families of specific enablers for monitoring environments and spaces in the Future Internet. These have been intially deployed and piloted in the ongoing ENVIROFI project of the FI-PPP programme [1]. Automated fusion and modelling of in situ and remote sensing data has been set up and the experimentation successfully conducted using RBF networks for the spatial fusion of water quality parameters measurements from satellite and stationary buoys in the Irish Sea. The RBF networks method scales for the spatial data fusion of multiple types of observation sources. This
Directory of Open Access Journals (Sweden)
van der Bij Wim
2005-09-01
Full Text Available Abstract Background In longitudinal studies on Health Related Quality of Life (HRQL it frequently occurs that patients have one or more missing forms, which may cause bias, and reduce the sample size. Aims of the present study were to address the problem of missing data in the field of lung transplantation (LgTX and HRQL, to compare results obtained with different methods of analysis, and to show the value of each type of statistical method used to summarize data. Methods Results from cross-sectional analysis, repeated measures on complete cases (ANOVA, and a multi-level analysis were compared. The scores on the dimension 'energy' of the Nottingham Health Profile (NHP after transplantation were used to illustrate the differences between methods. Results Compared to repeated measures ANOVA, the cross-sectional and multi-level analysis included more patients, and allowed for a longer period of follow-up. In contrast to the cross sectional analyses, in the complete case analysis, and the multi-level analysis, the correlation between different time points was taken into account. Patterns over time of the three methods were comparable. In general, results from repeated measures ANOVA showed the most favorable energy scores, and results from the multi-level analysis the least favorable. Due to the separate subgroups per time point in the cross-sectional analysis, and the relatively small number of patients in the repeated measures ANOVA, inclusion of predictors was only possible in the multi-level analysis. Conclusion Results obtained with the various methods of analysis differed, indicating some reduction of bias took place. Multi-level analysis is a useful approach to study changes over time in a data set where missing data, to reduce bias, make efficient use of available data, and to include predictors, in studies concerning the effects of LgTX on HRQL.
Progressive geometric algorithms
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Sander P.A. Alewijnse
2015-01-01
Full Text Available Progressive algorithms are algorithms that, on the way to computing a complete solution to the problem at hand, output intermediate solutions that approximate the complete solution increasingly well. We present a framework for analyzing such algorithms, and develop efficient progressive algorithms for two geometric problems: computing the convex hull of a planar point set, and finding popular places in a set of trajectories.
Institute of Scientific and Technical Information of China (English)
Ken K. Chin
2011-01-01
For semiconductors with localized intrinsic/impurity defects,intentionally doped or unintentionally incorporated,that have multiple transition energy levels among charge states,the general formulation of the local charge neutrality condition is given for the determination of the Fermi level and the majority carrier density.A graphical method is used to illustrate the solution of the problem.Relations among the transition energy levels of the multi-level defect are derived using the graphical method.Numerical examples are given for p-doping of the CdTe thin film used in solar panels and semi-insulating Si to illustrate the relevance and importance of the issues discussed in this work.
DESTINY: A Comprehensive Tool with 3D and Multi-Level Cell Memory Modeling Capability
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Sparsh Mittal
2017-09-01
Full Text Available To enable the design of large capacity memory structures, novel memory technologies such as non-volatile memory (NVM and novel fabrication approaches, e.g., 3D stacking and multi-level cell (MLC design have been explored. The existing modeling tools, however, cover only a few memory technologies, technology nodes and fabrication approaches. We present DESTINY, a tool for modeling 2D/3D memories designed using SRAM, resistive RAM (ReRAM, spin transfer torque RAM (STT-RAM, phase change RAM (PCM and embedded DRAM (eDRAM and 2D memories designed using spin orbit torque RAM (SOT-RAM, domain wall memory (DWM and Flash memory. In addition to single-level cell (SLC designs for all of these memories, DESTINY also supports modeling MLC designs for NVMs. We have extensively validated DESTINY against commercial and research prototypes of these memories. DESTINY is very useful for performing design-space exploration across several dimensions, such as optimizing for a target (e.g., latency, area or energy-delay product for a given memory technology, choosing the suitable memory technology or fabrication method (i.e., 2D v/s 3D for a given optimization target, etc. We believe that DESTINY will boost studies of next-generation memory architectures used in systems ranging from mobile devices to extreme-scale supercomputers. The latest source-code of DESTINY is available from the following git repository: https://bitbucket.org/sparshmittal/destinyv2.
A novel method for a multi-level hierarchical composite with brick-and-mortar structure.
Brandt, Kristina; Wolff, Michael F H; Salikov, Vitalij; Heinrich, Stefan; Schneider, Gerold A
2013-01-01
The fascination for hierarchically structured hard tissues such as enamel or nacre arises from their unique structure-properties-relationship. During the last decades this numerously motivated the synthesis of composites, mimicking the brick-and-mortar structure of nacre. However, there is still a lack in synthetic engineering materials displaying a true hierarchical structure. Here, we present a novel multi-step processing route for anisotropic 2-level hierarchical composites by combining different coating techniques on different length scales. It comprises polymer-encapsulated ceramic particles as building blocks for the first level, followed by spouted bed spray granulation for a second level, and finally directional hot pressing to anisotropically consolidate the composite. The microstructure achieved reveals a brick-and-mortar hierarchical structure with distinct, however not yet optimized mechanical properties on each level. It opens up a completely new processing route for the synthesis of multi-level hierarchically structured composites, giving prospects to multi-functional structure-properties relationships.
An Adaptive Hybrid Multi-level Intelligent Intrusion Detection System for Network Security
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P. Ananthi
2014-04-01
Full Text Available Intrusion Detection System (IDS plays a vital factor in providing security to the networks through detecting malicious activities. Due to the extensive advancements in the computer networking, IDS has become an active area of research to determine various types of attacks in the networks. A large number of intrusion detection approaches are available in the literature using several traditional statistical and data mining approaches. Data mining techniques in IDS observed to provide significant results. Data mining approaches for misuse and anomaly-based intrusion detection generally include supervised, unsupervised and outlier approaches. It is important that the efficiency and potential of IDS be updated based on the criteria of new attacks. This study proposes a novel Adaptive Hybrid Multi-level Intelligent IDS (AHMIIDS system which is the combined version of anomaly and misuse detection techniques. The anomaly detection is based on Bayesian Networks and then the misuse detection is performed using Adaptive Neuro Fuzzy Inference System (ANFIS. The outputs of both anomaly detection and misuse detection modules are applied to Decision Table Majority (DTM to perform the final decision making. A rule-base approach is used in this system. It is observed from the results that the proposed AHMIIDS performs better than other conventional hybrid IDS.
Robust point cloud classification based on multi-level semantic relationships for urban scenes
Zhu, Qing; Li, Yuan; Hu, Han; Wu, Bo
2017-07-01
The semantic classification of point clouds is a fundamental part of three-dimensional urban reconstruction. For datasets with high spatial resolution but significantly more noises, a general trend is to exploit more contexture information to surmount the decrease of discrimination of features for classification. However, previous works on adoption of contexture information are either too restrictive or only in a small region and in this paper, we propose a point cloud classification method based on multi-level semantic relationships, including point-homogeneity, supervoxel-adjacency and class-knowledge constraints, which is more versatile and incrementally propagate the classification cues from individual points to the object level and formulate them as a graphical model. The point-homogeneity constraint clusters points with similar geometric and radiometric properties into regular-shaped supervoxels that correspond to the vertices in the graphical model. The supervoxel-adjacency constraint contributes to the pairwise interactions by providing explicit adjacent relationships between supervoxels. The class-knowledge constraint operates at the object level based on semantic rules, guaranteeing the classification correctness of supervoxel clusters at that level. International Society of Photogrammetry and Remote Sensing (ISPRS) benchmark tests have shown that the proposed method achieves state-of-the-art performance with an average per-area completeness and correctness of 93.88% and 95.78%, respectively. The evaluation of classification of photogrammetric point clouds and DSM generated from aerial imagery confirms the method's reliability in several challenging urban scenes.
Networking health: multi-level marketing of health products in Ghana.
Droney, Damien
2016-01-01
Multi-level marketing (MLM0), a business model in which product distributors are compensated for enrolling further distributors as well as for selling products, has experienced dramatic growth in recent decades, especially in the so-called global South. This paper argues that the global success of MLM is due to its involvement in local health markets. While MLM has been subject to a number of critiques, few have analyzed the explicit health claims of MLM distributors. The majority of the products distributed through MLM are health products, which are presented as offering transformative health benefits. Based on interviews with MLM distributors in Ghana, but focusing on the experiences of one woman, this paper shows that MLM companies become intimately entwined with Ghanaian quests for health by providing their distributors with the materials to become informal health experts, allowing their distributors to present their products as medicines, and presenting MLM as an avenue to middle class cosmopolitanism. Ghanaian distributors promote MLM products as medically powerful, and the distribution of these products as an avenue to status and profit. As a result, individuals seeking health become a part of ethically questionable forms of medical provision based on the exploitation of personal relationships. The success of MLM therefore suggests that the health industry is at the forefront of transnational corporations' extraction of value from informal economies, drawing on features of health markets to monetize personal relationships.
Ecological relevance of Sentinels' biomarker responses: a multi-level approach.
Seabra Pereira, Camilo D; Abessa, Denis M S; Choueri, Rodrigo B; Almagro-Pastor, Victor; Cesar, Augusto; Maranho, Luciane A; Martín-Díaz, María Laura; Torres, Ronaldo J; Gusso-Choueri, Paloma K; Almeida, João E; Cortez, Fernando S; Mozeto, Antonio A; Silbiger, Helcy L N; Sousa, Eduinetty C P M; Del Valls, Tommas Angel; Bainy, Afonso C D
2014-05-01
In response to the need for more sensitive and rapid indicators of environmental quality, sublethal effects on the lowest levels of biological organization have been investigated. The ecological relevance of these responses assumes a prevailing role to assure effectiveness as indicator of ecological status. This study aimed to investigate the linkages between biomarker responses of caged bivalves and descriptive parameters of macrobenthic community structure. For this purpose a multi-level environmental assessment of marine and estuarine zones was performed in São Paulo coast, Brazil. Multivariate analysis was applied to identify linkages between biological responses and ecological indices, as well as to characterizing the studied stations. Individuals of the marine mussel Perna perna caged along Santos Bay showed signs of oxidative stress, lysosomal membrane destabilization, histological alterations and reduced embryonic development. The estuarine oyster Crassostrea rhizophorae caged along Santos Port Channel showed alterations on biotransformation enzymes and antioxidant system, DNA damage and lysosomal membrane destabilization. The benthic community analysis showed reduced richness and diversity in the same areas of the Santos bay and estuary where biomarker responses were altered. Our results revealed that xenobiotics are inducing physiological stress, which may lead to changes of the benthic community structure and deterioration of the ecological status over time. Integrating biomarker responses and ecological indexes improved certainty that alterations found at community level could be related to xenobiotic as stressors, which was very useful to improve the discriminatory power of the environmental assessment. Copyright © 2013 Elsevier Ltd. All rights reserved.
MKEM: a Multi-level Knowledge Emergence Model for mining undiscovered public knowledge
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Song Min
2010-04-01
Full Text Available Abstract Background Since Swanson proposed the Undiscovered Public Knowledge (UPK model, there have been many approaches to uncover UPK by mining the biomedical literature. These earlier works, however, required substantial manual intervention to reduce the number of possible connections and are mainly applied to disease-effect relation. With the advancement in biomedical science, it has become imperative to extract and combine information from multiple disjoint researches, studies and articles to infer new hypotheses and expand knowledge. Methods We propose MKEM, a Multi-level Knowledge Emergence Model, to discover implicit relationships using Natural Language Processing techniques such as Link Grammar and Ontologies such as Unified Medical Language System (UMLS MetaMap. The contribution of MKEM is as follows: First, we propose a flexible knowledge emergence model to extract implicit relationships across different levels such as molecular level for gene and protein and Phenomic level for disease and treatment. Second, we employ MetaMap for tagging biological concepts. Third, we provide an empirical and systematic approach to discover novel relationships. Results We applied our system on 5000 abstracts downloaded from PubMed database. We performed the performance evaluation as a gold standard is not yet available. Our system performed with a good precision and recall and we generated 24 hypotheses. Conclusions Our experiments show that MKEM is a powerful tool to discover hidden relationships residing in extracted entities that were represented by our Substance-Effect-Process-Disease-Body Part (SEPDB model.
A frozen Gaussian approximation-based multi-level particle swarm optimization for seismic inversion
Energy Technology Data Exchange (ETDEWEB)
Li, Jinglai, E-mail: jinglaili@sjtu.edu.cn [Institute of Natural Sciences, Department of Mathematics, and MOE Key Laboratory of Scientific and Engineering Computing, Shanghai Jiao Tong University, Shanghai 200240 (China); Lin, Guang, E-mail: lin491@purdue.edu [Department of Mathematics, School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907 (United States); Computational Sciences and Mathematics Division, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Yang, Xu, E-mail: xuyang@math.ucsb.edu [Department of Mathematics, University of California, Santa Barbara, CA 93106 (United States)
2015-09-01
In this paper, we propose a frozen Gaussian approximation (FGA)-based multi-level particle swarm optimization (MLPSO) method for seismic inversion of high-frequency wave data. The method addresses two challenges in it: First, the optimization problem is highly non-convex, which makes hard for gradient-based methods to reach global minima. This is tackled by MLPSO which can escape from undesired local minima. Second, the character of high-frequency of seismic waves requires a large number of grid points in direct computational methods, and thus renders an extremely high computational demand on the simulation of each sample in MLPSO. We overcome this difficulty by three steps: First, we use FGA to compute high-frequency wave propagation based on asymptotic analysis on phase plane; Then we design a constrained full waveform inversion problem to prevent the optimization search getting into regions of velocity where FGA is not accurate; Last, we solve the constrained optimization problem by MLPSO that employs FGA solvers with different fidelity. The performance of the proposed method is demonstrated by a two-dimensional full-waveform inversion example of the smoothed Marmousi model.
Presenting a Multi-level Superstructure Optimization Approach for Mechatronic System Design
DEFF Research Database (Denmark)
Pedersen, Henrik C.; Andersen, Torben Ole; Bech, Michael Møller
2010-01-01
Synergism and integration in the design process is what sets apart a Mechatronic System from a traditional, multidisciplinary system. However the typical design approach has been to divide the design problem into sub problems for each technology area (mechanics, electronics and control) and descr......Synergism and integration in the design process is what sets apart a Mechatronic System from a traditional, multidisciplinary system. However the typical design approach has been to divide the design problem into sub problems for each technology area (mechanics, electronics and control......) and describe the interface between the technologies, whereas the lack of well-established, systematic engineering methods to form the basic set-off in analysis and design of complete mechatronic systems has been obvious. The focus of the current paper is therefore to present an integrated design approach...... for mechatronic system design, utilizing a multi-level superstructure optimization based approach. Finally two design examples are presented and the possibilities and limitations of the approach are outlined....
Interevent time distributions of human multi-level activity in a virtual world
Mryglod, O.; Fuchs, B.; Szell, M.; Holovatch, Yu.; Thurner, S.
2015-02-01
Studying human behavior in virtual environments provides extraordinary opportunities for a quantitative analysis of social phenomena with levels of accuracy that approach those of the natural sciences. In this paper we use records of player activities in the massive multiplayer online game Pardus over 1238 consecutive days, and analyze dynamical features of sequences of actions of players. We build on previous work where temporal structures of human actions of the same type were quantified, and provide an empirical understanding of human actions of different types. This study of multi-level human activity can be seen as a dynamic counterpart of static multiplex network analysis. We show that the interevent time distributions of actions in the Pardus universe follow highly non-trivial distribution functions, from which we extract action-type specific characteristic 'decay constants'. We discuss characteristic features of interevent time distributions, including periodic patterns on different time scales, bursty dynamics, and various functional forms on different time scales. We comment on gender differences of players in emotional actions, and find that while males and females act similarly when performing some positive actions, females are slightly faster for negative actions. We also observe effects on the age of players: more experienced players are generally faster in making decisions about engaging in and terminating enmity and friendship, respectively.
Multi-level Simulation of a Real Time Vibration Monitoring System Component
Robertson, Bryan A.; Wilkerson, Delisa
2005-01-01
This paper describes the development of a custom built Digital Signal Processing (DSP) printed circuit board designed to implement the Advanced Real Time Vibration Monitoring Subsystem proposed by Marshall Space Flight Center (MSFC) Transportation Directorate in 2000 for the Space Shuttle Main Engine Advanced Health Management System (AHMS). This Real Time Vibration Monitoring System (RTVMS) is being developed for ground use as part of the AHMS Health Management Computer-Integrated Rack Assembly (HMC-IRA). The HMC-IRA RTVMS design contains five DSPs which are highly interconnected through individual communication ports, shared memory, and a unique communication router that allows all the DSPs to receive digitized data fiom two multi-channel analog boards simultaneously. This paper will briefly cover the overall board design but will focus primarily on the state-of-the-art simulation environment within which this board was developed. This 16-layer board with over 1800 components and an additional mezzanine card has been an extremely challenging design. Utilization of a Mentor Graphics simulation environment provided the unique board and system level simulation capability to ascertain any timing or functional concerns before production. By combining VHDL, Synopsys Software and Hardware Models, and the Mentor Design Capture Environment, multiple simulations were developed to verify the RTVMS design. This multi-level simulation allowed the designers to achieve complete operability without error the first time the RTVMS printed circuit board was powered. The HMC-IRA design has completed all engineering and deliverable unit testing. P
Modelling and simulation of complex systems: an approach based on multi-level agents
Directory of Open Access Journals (Sweden)
Alain-Jerome Fougeres
2011-11-01
Full Text Available A complex system is made up of many components with many interactions. So the design of systems such as simulation systems, cooperative systems or assistance systems includes a very accurate modelling of interactional and communicational levels. The agent-based approach provides an adapted abstraction level for this problem. After having studied the organizational context and communicative capacities of agent-based systems, to simulate the reorganization of a flexible manufacturing, to regulate an urban transport system, and to simulate an epidemic detection system, our thoughts on the interactional level were inspired by human-machine interface models, especially those in cognitive engineering To provide a general framework for agent-based complex systems modelling, we then proposed a scale of four behaviours that agents may adopt in their complex systems (reactive, routine, cognitive, and collective. To complete the description of multi-level agent models, which is the focus of this paper, we illustrate our modelling and discuss our ongoing work on each level.
MK4MDD: a multi-level knowledge base and analysis platform for major depressive disorder.
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Liyuan Guo
Full Text Available BACKGROUND: Major depressive disorder (MDD is a complex neuropsychiatric syndrome with high heterogeneity. There are different levels of biological components that underlie MDD and interact with each other. To uncover the disease mechanism, large numbers of studies at different levels have been conducted. There is a growing need to integrate data from multiple levels of research into a database to provide a systematic review of current research results. The cross level integration will also help bridge gaps of different research levels for further understanding on MDD. So far, there has been no such effort for MDD. DESCRIPTIONS: We offer researchers a Multi-level Knowledge base for MDD (MK4MDD to study the interesting interplay of components in the pathophysiological cascade of MDD from genetic variations to diagnostic syndrome. MK4MDD contains 2,341 components and 5,206 relationships between components based on reported experimental results obtained by diligent literature reading with manual curation. All components were well classified with careful curation and supplementary annotation. The powerful search and visualization tools make all data in MK4MDD form a cross-linked network to be applied to a broad range of both basic and applied research. CONCLUSIONS: MK4MDD aims to provide researchers with a central knowledge base and analysis platform for MDD etiological and pathophysiological mechanisms research. MK4MDD is freely available at http://mdd.psych.ac.cn.
Directory of Open Access Journals (Sweden)
H. Frey
2010-02-01
Full Text Available In the course of glacier retreat, new glacier lakes can develop. As such lakes can be a source of natural hazards, strategies for predicting future glacier lake formation are important for an early planning of safety measures. In this article, a multi-level strategy for the identification of overdeepened parts of the glacier beds and, hence, sites with potential future lake formation, is presented. At the first two of the four levels of this strategy, glacier bed overdeepenings are estimated qualitatively and over large regions based on a digital elevation model (DEM and digital glacier outlines. On level 3, more detailed and laborious models are applied for modeling the glacier bed topography over smaller regions; and on level 4, special situations must be investigated in-situ with detailed measurements such as geophysical soundings. The approaches of the strategy are validated using historical data from Trift Glacier, where a lake formed over the past decade. Scenarios of future glacier lakes are shown for the two test regions Aletsch and Bernina in the Swiss Alps. In the Bernina region, potential future lake outbursts are modeled, using a GIS-based hydrological flow routing model. As shown by a corresponding test, the ASTER GDEM and the SRTM DEM are both suitable to be used within the proposed strategy. Application of this strategy in other mountain regions of the world is therefore possible as well.
Multi-levelling and externalizing migration and asylum: lessons from the southern European islands
Directory of Open Access Journals (Sweden)
Anna Triandafyllidou
2014-05-01
Full Text Available Southern European countries have come to constitute the most vulnerable external border of the European Union (EU over the last decade. Irregular migration pressures have been acutely felt on the EU’s southern sea borders, and particularly on four sets of islands: Canary Islands (Spain, Lampedusa and Linosa (Italy, Malta, and Aegean Islands (Greece. This quartet is, to a large extent, used as stepping stones by irregular migrants and asylum seekers to reach the European continent. This paper studies the role of these islands as ‘outposts’ of a framework of externalization. It starts by discussing the notion of externalization and its different facets. It considers how externalization is linked to both fencing and gate-keeping strategies of migration and asylum control. The second part of the paper focuses on the special role of the island quartet with respect to the externalization web cast by national and EU-wide migration policies. It concludes with a critical reflection on the multi-level character of externalization policies and practices that occur both within the EU and between the EU and third countries.
Re-configurable multi-level temperature sensing by ultrasonic "spring-like" helical waveguide
Periyannan, Suresh; Rajagopal, Prabhu; Balasubramaniam, Krishnan
2016-04-01
This paper introduces a novel technique for multi-level temperature measurement using a single reconfigurable ultrasonic wire waveguide that is configured in the form of a helical spring. In this embodiment, the multiple sensing levels located along the length of the helical waveguide wire can be repositioned by stretching or collapsing the spring to provide measurements at different desired spacing in a given area/volume. This method can measure over a wide range of temperatures. The transduction is performed using Piezo-electric crystals that are attached to one end of the waveguide which act as transmitter as well as receiver. The wire will have multiple reflector embodiments (notches was used here) that allow reflections of input L(0,1) mode guided ultrasonic wave, in pulse echo mode, back to the crystal. Using the time of fight measurement at multiple predefined reflector locations, the local average temperatures are measured and compared with co-located thermocouples. The finite element modeling simulation was used to study the effect of excitation frequency and the mean coil diameter of the "spring-like" waveguide. This technique improves on the limitations of a straight waveguide technique earlier reported.
MetricForensics: A Multi-Level Approach for Mining Volatile Graphs
Energy Technology Data Exchange (ETDEWEB)
Henderson, Keith [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Eliassi-Rad, Tina [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Faloutsos, Christos [Carnegie Mellon Univ., Pittsburgh, PA (United States); Akoglu, Leman [Carnegie Mellon Univ., Pittsburgh, PA (United States); Li, Lei [Carnegie Mellon Univ., Pittsburgh, PA (United States); Maruhashi, Koji [Fujitsu Laboratories Ltd., Kanagawa (Japan); Prakash, B. Aditya [Carnegie Mellon Univ., Pittsburgh, PA (United States); Tong, H [Carnegie Mellon Univ., Pittsburgh, PA (United States)
2010-02-08
Advances in data collection and storage capacity have made it increasingly possible to collect highly volatile graph data for analysis. Existing graph analysis techniques are not appropriate for such data, especially in cases where streaming or near-real-time results are required. An example that has drawn significant research interest is the cyber-security domain, where internet communication traces are collected and real-time discovery of events, behaviors, patterns and anomalies is desired. We propose MetricForensics, a scalable framework for analysis of volatile graphs. MetricForensics combines a multi-level “drill down" approach, a collection of user-selected graph metrics and a collection of analysis techniques. At each successive level, more sophisticated metrics are computed and the graph is viewed at a finer temporal resolution. In this way, MetricForensics scales to highly volatile graphs by only allocating resources for computationally expensive analysis when an interesting event is discovered at a coarser resolution first. We test MetricForensics on three real-world graphs: an enterprise IP trace, a trace of legitimate and malicious network traffic from a research institution, and the MIT Reality Mining proximity sensor data. Our largest graph has »3M vertices and »32M edges, spanning 4:5 days. The results demonstrate the scalability and capability of MetricForensics in analyzing volatile graphs; and highlight four novel phenomena in such graphs: elbows, broken correlations, prolonged spikes, and strange stars.
OAHG: an integrated resource for annotating human genes with multi-level ontologies
Cheng, Liang; Sun, Jie; Xu, Wanying; Dong, Lixiang; Hu, Yang; Zhou, Meng
2016-01-01
OAHG, an integrated resource, aims to establish a comprehensive functional annotation resource for human protein-coding genes (PCGs), miRNAs, and lncRNAs by multi-level ontologies involving Gene Ontology (GO), Disease Ontology (DO), and Human Phenotype Ontology (HPO). Many previous studies have focused on inferring putative properties and biological functions of PCGs and non-coding RNA genes from different perspectives. During the past several decades, a few of databases have been designed to annotate the functions of PCGs, miRNAs, and lncRNAs, respectively. A part of functional descriptions in these databases were mapped to standardize terminologies, such as GO, which could be helpful to do further analysis. Despite these developments, there is no comprehensive resource recording the function of these three important types of genes. The current version of OAHG, release 1.0 (Jun 2016), integrates three ontologies involving GO, DO, and HPO, six gene functional databases and two interaction databases. Currently, OAHG contains 1,434,694 entries involving 16,929 PCGs, 637 miRNAs, 193 lncRNAs, and 24,894 terms of ontologies. During the performance evaluation, OAHG shows the consistencies with existing gene interactions and the structure of ontology. For example, terms with more similar structure could be associated with more associated genes (Pearson correlation γ2 = 0.2428, p < 2.2e–16). PMID:27703231
Directory of Open Access Journals (Sweden)
Kennon M. Sheldon
2009-12-01
Full Text Available This article begins with a consideration of what is missing in positive psychology – namely, an integrative framework within which to view the entire person, especially as nested within more-or-less supportive social contexts and cultures. Thus, I presented a multi-level hierarchical framework for considering and explaining human behavior, arguing that all levels of the framework are necessary for complete exposition. From this point of view, personality processes cannot be reduced to "mere" cognitive processes; there are trans-cognitive rules and laws operating at this higher level. I also considered a four level sub-framework within the personality level of analysis, consisting of organismic needs/characteristics, traits/dispositions, goals/intentions, and self/self-narratives. I contended that each of these spheres of the person operates via unique rules and regularities, processes that cannot be reduced to lower levels of analysis (such as biological, neurological, and cognitive levels of analysis. Finally, I described some recent research that simultaneously examines factors at multiple levels of the SLOPIC model, showing that each has influence for predicting SWB, and moreover, that all of these effects are mediated by basic need satisfaction. Hopefully this line of research will prove useful for other positive psychologists seeking "the big picture" on human flourishing.
DReAM: Demand Response Architecture for Multi-level District Heating and Cooling Networks
Energy Technology Data Exchange (ETDEWEB)
Bhattacharya, Saptarshi; Chandan, Vikas; Arya, Vijay; Kar, Koushik
2017-05-19
In this paper, we exploit the inherent hierarchy of heat exchangers in District Heating and Cooling (DHC) networks and propose DReAM, a novel Demand Response (DR) architecture for Multi-level DHC networks. DReAM serves to economize system operation while still respecting comfort requirements of individual consumers. Contrary to many present day DR schemes that work on a consumer level granularity, DReAM works at a level of hierarchy above buildings, i.e. substations that supply heat to a group of buildings. This improves the overall DR scalability and reduce the computational complexity. In the first step of the proposed approach, mathematical models of individual substations and their downstream networks are abstracted into appropriately constructed low-complexity structural forms. In the second step, this abstracted information is employed by the utility to perform DR optimization that determines the optimal heat inflow to individual substations rather than buildings, in order to achieve the targeted objectives across the network. We validate the proposed DReAM framework through experimental results under different scenarios on a test network.
分层电力市场刍议%A MULTI-LEVEL ELECTRICITY MARKET APPROACH
Institute of Scientific and Technical Information of China (English)
傅书逖; 白晓民
2001-01-01
提出了一种分层电力市场模式，即在省级电力市场之上还有区域级的电力市场，两者同时并存而协调工作。论文指出，只要全网采用统一的市场结算价格(MCP), 就可以达到与集中模式同样的效果，而且无论送电省或受电省都可以从中受益。文中附有简单例题。%In this paper a multi-level electricity market approach is presented.In this approach one regional electricity market and several provincial electricity markets may co-exist and operate in coordination. It has been shown that if a unified MCP is used in all provincial electricity markets, same effect as the centralized model can be achieved, and both the sending provinces and receiving provinces would be benefited. A simplified numerical example is attached.
Presenting a Multi-level Superstructure Optimization Approach for Mechatronic System Design
DEFF Research Database (Denmark)
Pedersen, Henrik C.; Andersen, Torben Ole; Bech, Michael Møller
2010-01-01
Synergism and integration in the design process is what sets apart a Mechatronic System from a traditional, multidisciplinary system. However the typical design approach has been to divide the design problem into sub problems for each technology area (mechanics, electronics and control) and descr......Synergism and integration in the design process is what sets apart a Mechatronic System from a traditional, multidisciplinary system. However the typical design approach has been to divide the design problem into sub problems for each technology area (mechanics, electronics and control......) and describe the interface between the technologies, whereas the lack of well-established, systematic engineering methods to form the basic set-off in analysis and design of complete mechatronic systems has been obvious. The focus of the current paper is therefore to present an integrated design approach...... for mechatronic system design, utilizing a multi-level superstructure optimization based approach. Finally two design examples are presented and the possibilities and limitations of the approach are outlined....
Economic sustainability, water security and multi-level governance of local water schemes in Nepal
Directory of Open Access Journals (Sweden)
Emma Hakala
2017-07-01
Full Text Available This article explores the role of multi-level governance and power structures in local water security through a case study of the Nawalparasi district in Nepal. It focuses on economic sustainability as a measure to address water security, placing this thematic in the context of a complicated power structure consisting of local, district and national administration as well as external development cooperation actors. The study aims to find out whether efforts to improve the economic sustainability of water schemes have contributed to water security at the local level. In addition, it will consider the interactions between water security, power structures and local equality and justice. The research builds upon survey data from the Nepalese districts of Nawalparasi and Palpa, and a case study based on interviews and observation in Nawalparasi. The survey was performed in water schemes built within a Finnish development cooperation programme spanning from 1990 to 2004, allowing a consideration of the long-term sustainability of water management projects. This adds a crucial external influence into the intra-state power structures shaping water management in Nepal. The article thus provides an alternative perspective to cross-regional water security through a discussion combining transnational involvement with national and local points of view.
Westra, Daan; Angeli, Federica; Carree, Martin; Ruwaard, Dirk
2017-08-01
Cooperative inter-organizational relations are salient to healthcare delivery. However, they do not match with the pro-competitive healthcare reforms implemented in several countries. Healthcare organizations thus need to balance competition and cooperation in a situation of 'coopetition'. In this paper we study the individual and organizational determinants of coopetition versus those of cooperation in the price-competitive specialized care sector of the Netherlands. We use shared medical specialists as a proxy of collaboration between healthcare organizations. Based on a sample of 15,431 medical specialists and 371 specialized care organizations from March 2016, one logistic multi-level model is used to predict medical specialists' likelihood to be shared and another to predict their likelihood to be shared to a competitor. We find that different organizations share different specialists to competitors and non-competitors. Cooperation and coopetition are hence distinct organizational strategies in health care. Cooperation manifests through spin-off formation. Coopetition occurs most among organizations in the price-competitive market segment but in alternative geographical markets. Hence, coopetition in health care does not appear to be particularly anti-competitive. However, healthcare organizations seem reluctant to share their most specialized human resources, limiting the knowledge-sharing effects of this type of relation. Therefore, it remains unclear whether coopetition in health care is beneficial to patients. Copyright © 2017 Elsevier Ltd. All rights reserved.
Institute of Scientific and Technical Information of China (English)
Chang-yin Zhou; Guo-ping He; Yong-li Wang
2006-01-01
In this paper,we propose a feasible QP-free method for solving nonlinear inequality constrained optimization problems. A new working set is proposed to estimate the active set. Specially,to determine the working set,the new method makes use of the multiplier information from the previous iteration,eliminating the need to compute a multiplier function. At each iteration,two or three reduced symmetric systems of linear equations with a common coefficient matrix involving only constraints in the working set are solved,and when the iterate is sufficiently close to a KKT point,only two of them are involved.Moreover,the new algorithm is proved to be globally convergent to a KKT point under mild conditions. Without assuming the strict complementarity,the convergence rate is superlinear under a condition weaker than the strong second-order sufficiency condition. Numerical experiments illustrate the efficiency of the algorithm.
Carracciuolo, Luisa; D'Amore, Luisa; Murli, Almerico
1998-10-01
We explore the filtering properties of wavelets functions in order to develop accurate and efficient numerical algorithms for Image Restoration problems. We propose a parallel implementation for MIMD distributed memory environments. The key insight of our approach is the use of distributed versions of Level 3 Basic Linear Algebra Subprograms as computational building blocks and the use of Basic Linear Algebra Communication Subprograms as communication building blocks for advanced architecture computers. The use of these low-level mathematical software libraries guarantees the development of efficient, portable and scalable high-level algorithms and hides many details of the parallelism from the user's point of view. Numerical experiments on a simulated image restoration applications are shown. The parallel software has been tested on a 12 nodes IBM SP2 available at the Center for Research on Parallel Computing and Supercomputers in Naples, Italy).
Liu, Ming; Zhao, Lindu
2012-08-01
Demand for emergency resources is usually uncertain and varies quickly in anti-bioterrorism system. Besides, emergency resources which had been allocated to the epidemic areas in the early rescue cycle will affect the demand later. In this article, an integrated and dynamic optimisation model with time-varying demand based on the epidemic diffusion rule is constructed. The heuristic algorithm coupled with the MATLAB mathematical programming solver is adopted to solve the optimisation model. In what follows, the application of the optimisation model as well as a short sensitivity analysis of the key parameters in the time-varying demand forecast model is presented. The results show that both the model and the solution algorithm are useful in practice, and both objectives of inventory level and emergency rescue cost can be controlled effectively. Thus, it can provide some guidelines for decision makers when coping with emergency rescue problem with uncertain demand, and offers an excellent reference when issues pertain to bioterrorism.
Hassink, J.; Grin, J.; Hulsink, W.
2013-01-01
Care farming is a promising example of multifunctional agriculture: it is an innovation at the crossroads of the agricultural and healthcare sectors. Our objective is to develop a framework for understanding the success of initiatives in this field. We link empirical data with the multi-level perspe
Hassink, J.; Grin, J.; Hulsink, W.
2013-01-01
Care farming is a promising example of multifunctional agriculture: it is an innovation at the crossroads of the agricultural and healthcare sectors. Our objective is to develop a framework for understanding the success of initiatives in this field. We link empirical data with the multi-level perspe
Doyle, Louise; Kelliher, Felicity; Harrington, Denis
2016-01-01
The aim of this paper is to review the relevant literature on organisational learning and offer a preliminary conceptual framework as a basis to explore how the multi-levels of individual learning and team learning interact in a public healthcare organisation. The organisational learning literature highlights a need for further understanding of…
Vieira, Rodrigo Drumond; Kelly, Gregory J.
2014-01-01
In this paper, we present and apply a multi-level method for discourse analysis in science classrooms. This method is based on the structure of human activity (activity, actions, and operations) and it was applied to study a pre-service physics teacher methods course. We argue that such an approach, based on a cultural psychological perspective,…
Hatzichristiou, Chryse; Issari, Philia; Lykitsakou, Konstantina; Lampropoulou, Aikaterini; Dimitropoulou, Panayiota
2011-01-01
This article proposes a multi-level model for crisis preparedness and intervention in the Greek educational system. It presents: a) a brief overview of leading models of school crisis preparedness and intervention as well as cultural considerations for contextually relevant crisis response; b) a description of existing crisis intervention…
Hassink, J.; Grin, J.; Hulsink, W.
2013-01-01
Care farming is a promising example of multifunctional agriculture: it is an innovation at the crossroads of the agricultural and healthcare sectors. Our objective is to develop a framework for understanding the success of initiatives in this field. We link empirical data with the multi-level
Tessema Abissa, Fisseha; Tessema Abissa, Fisseha
2014-01-01
This thesis examines the relationships between multi-leveled decision structures for climate technology transfer through an analysis of top-down macro-policy and bottom-up micro-implementation. It examines how international climate technology transfer policy under the UNFCCC filters down to the
Tessema Abissa, Fisseha
2014-01-01
This thesis examines the relationships between multi-leveled decision structures for climate technology transfer through an analysis of top-down macro-policy and bottom-up micro-implementation. It examines how international climate technology transfer policy under the UNFCCC filters down to the nati
Vieira, Rodrigo Drumond; Kelly, Gregory J.
2014-01-01
In this paper, we present and apply a multi-level method for discourse analysis in science classrooms. This method is based on the structure of human activity (activity, actions, and operations) and it was applied to study a pre-service physics teacher methods course. We argue that such an approach, based on a cultural psychological perspective,…
Optimal Mixing Evolutionary Algorithms
Thierens, D.; Bosman, P.A.N.; Krasnogor, N.
2011-01-01
A key search mechanism in Evolutionary Algorithms is the mixing or juxtaposing of partial solutions present in the parent solutions. In this paper we look at the efficiency of mixing in genetic algorithms (GAs) and estimation-of-distribution algorithms (EDAs). We compute the mixing probabilities of
Energy Technology Data Exchange (ETDEWEB)
Moeini, R.; Afshar, M.H.
2011-07-15
Hydropower is currently the number one source of electricity production in the world. For the design and construction of such systems, mathematical modelling is often use for reservoir operations. As conventional methods present some shortcomings in solving reservoir operation problems, a new method is presented here. It consists in an arc-based formulation of hydropower reservoir operation problems which can be applied to ant colony optimization algorithms. This paper first described this formulation and then applied it to solve two hydropower reservoir operation problems. The results showed that this formulation can optimally solve large-scale hydropower reservoir operation problems while offering a clear definition of heuristic information.
多级网络编码方案%Multi-level network coding scheme
Institute of Scientific and Technical Information of China (English)
宋雪; 周异辉; 师军; 吴振强
2015-01-01
目前安全网络编码的研究有信息论安全和密码学安全两种方法。信息论安全的编码方案中，中继节点编码主要是使用随机线性网络编码（RLNC）生成编码矩阵，但是此方法并不能保证生成的矩阵一定满秩，从而影响方案的解码率。提出了一个多级网络编码（MLNC）方案，该方案通过在源端使用对角矩阵对消息进行编码，以降低编码复杂度；在中继节点，让入度大于等于2的节点作为编码节点，使用多级的网络编码使混淆效果更好，编码节点随机生成满秩的下三角矩阵和上三角矩阵，用它们的乘积作为编码矩阵，这样能保证编码矩阵满秩，接收节点可以成功解码。Matlab仿真结果表明，MLNC编码矩阵达到k-安全概率优于RLNC编码矩阵，并证明MLNC方案满足信息论安全。%The current secure network coding has two methods.They are information-theoretic security and cryptography security. Among the encoding methods of information-theoretic security, the encoding scheme of the relay node uses the Random Linear Network Coding(RLNC)to generate the encoding matrix. But this method does not guarantee that the resulting matrix must be full rank and affects the decoding rate. This paper proposes a Multi-Level Network Coding(MLNC) scheme. The scheme uses the triangle matrix to encode source message. On the relay node, the node whose degree is greater than or equal to 2 is used as coding node, using multi-level network coding can make the message encode mix better. The encoding nodes generate the full rank lower triangular matrix and the full rank upper triangular matrix randomly. It uses their product as an encoding matrix. This scheme will ensure encoding matrix must be full rank. The receiving node can successfully decode the data. The result of the Matlab simulation shows that the probability of the coding matrix of MLNC satisfying k-secure can be better than RLNC. And the scheme
Multi-level intervention to prevent influenza infections in older low income and minority adults.
Schensul, Jean J; Radda, Kim; Coman, Emil; Vazquez, Elsie
2009-06-01
In this paper we describe a successful multi-level participatory intervention grounded in principles of individual and group empowerment, and guided by social construction theory. The intervention addressed known and persistent inequities in influenza vaccination among African American and Latino older adults, and associated infections, hospitalizations and mortality. It was designed to increase resident ability to make informed decisions about vaccination, and to build internal and external infrastructure to support sustainability over time. The intervention brought a group of social scientists, vaccine researchers, geriatricians, public health nurses, elder services providers and advocates together with senior housing management and activist African American and Latino residents living in public senior housing in a small east coast city. Two buildings of equal size and similar ethnic composition were randomized as intervention and control buildings. Pre and post intervention surveys were conducted in both buildings, measuring knowledge, attitudes and peer norms. Processes and outcomes were documented at four levels: Influenza Strategic Alliance (macro and exo levels), building management (meso level), building resident committee (meso level) and individual residents. The Influenza Strategic Alliance (I.S.A.) provided ongoing resources, information and vaccine; the building management provided economic and other in-kind resources and supported residents to continue flu clinics in the building. The V.I.P. Resident Committee conducted flu campaigns with flu clinics in English and Spanish. The vaccination rate in the intervention building at post test exceeded the study goal of 70% and showed a significant improvement over the control building. The intervention achieved desired outcomes at all four levels and resulted in a significant increase in influenza vaccination, and improvements in pro-vaccination knowledge, beliefs, and understanding of health consequences.
Pictorial AR Tag with Hidden Multi-Level Bar-Code and Its Potential Applications
Directory of Open Access Journals (Sweden)
Huy Le
2017-09-01
Full Text Available For decades, researchers have been trying to create intuitive virtual environments by blending reality and virtual reality, thus enabling general users to interact with the digital domain as easily as with the real world. The result is “augmented reality” (AR. AR seamlessly superimposes virtual objects on to a real environment in three dimensions (3D and in real time. One of the most important parts that helps close the gap between virtuality and reality is the marker used in the AR system. While pictorial marker and bar-code marker are the two most commonly used marker types in the market, they have some disadvantages in visual and processing performance. In this paper, we present a novelty method that combines the bar-code with the original feature of a colour picture (e.g., photos, trading cards, advertisement’s figure. Our method decorates on top of the original pictorial images additional features with a single stereogram image that optically conceals a multi-level (3D bar-code. Thus, it has a larger capability of storing data compared to the general 1D barcode. This new type of marker has the potential of addressing the issues that the current types of marker are facing. It not only keeps the original information of the picture but also contains encoded numeric information. In our limited evaluation, this pictorial bar-code shows a relatively robust performance under various conditions and scaling; thus, it provides a promising AR approach to be used in many applications such as trading card games, educations, and advertisements.
A multi-level assessment of a program to teach medical students to teach.
Blatt, Benjamin; Greenberg, Larrie
2007-02-01
Few longitudinal programs exist to teach senior students (MS4s) to be teachers, nor have there been any reports of comprehensive program evaluation in this area. The primary objectives of this study were to describe our ongoing faculty development effort and to develop a multi-level program evaluation, using Dixon's model. The TALKS (Teaching and Learning Communication Skills) program is a senior elective and open to all MS4s. We evaluated our program through assessment of its participants at three levels: level 1, opinion; level 2, competence; and level 3, performance; but not level 4, patient outcomes. The authors used a retrospective, pre-post questionnaire to assess MS4 attitudes about their educational experiences, a traditional instrument to assess their teaching, an interaction analysis technique using Bloom's taxonomy to assess MS4s' feedback skills, and a SP exam to assess MS4 communication skills. The authors hypothesized that MS4s participating in TALKS would view medical education more positively and informatively, would demonstrate important principles in giving feedback, would be assessed as excellent teachers, and would perform better than controls in an SP exam emphasizing communication skills. Results revealed that MS4s' ratings as teachers were very good to excellent, with the highest scores on the items "knowledgeable, supportive of me, and answering questions clearly." (Level 1, Opinion) MS4s' perceptions of their knowledge, attitudes and skills increased significantly from the pre to the post-questionnaire. (Level 2, Competence) MS4 feedback skills to MS2s revealed they did more talking than ideal, often at the lowest levels of Bloom's taxonomy. (Level 3, Performance) MS4s demonstrated better communication skills than controls on an evaluation by professional SPs. (Level 3, Performance).
龙虾树的多级距离标号%The Multi-level Distance Labeling for Lobster Tree
Institute of Scientific and Technical Information of China (English)
侯丽霞; 左连翠
2011-01-01
连通图G的多级距离标号是指顶点集y(G)到{0,1,2,…}的一个映射f,它使得对于任意的u,u∈y(G)满足:|f(u) - f(v)|≥diam(G)+1-d(u,u),其中diam(G)是图G的直径,d(u,v)是两点u,u之间的距离.函数f的跨度是指max u,v∈V(G){f(u)-f(v)}.图G的多级距离数是指它的所有多级距离标号的最小跨度.本文研究了一类关于权中心点对称的龙虾树,并得出了它的多级距离数的一个下界,进而得出了它在某些特殊情况下的多级距离数的确切值.%The multi-level distance labeling for a connected graph G is a function f : V(G) →{0,1,2, …}, so that the following is satisfied for u,v ∈ V(G): ∣f(u) - f(v)∣ ≥ diam (G) + 1 - d(u, v), where diam (G) is the diameter of G, d(u, v) is the distance between u,v. The span of / is denned as max {f(u) - f(v)}. The multi-level distance number ofu,v∈V(G)G is the minimum span of a multi-level distance labeling for G. A class of symmetric lobster tree about weight center is investigated, and it's a lower bound of the multi-level distance number is obtained, and then the exact number in some special cases of the multi-level distance number is obtained.
Directory of Open Access Journals (Sweden)
DAHIYA, P.
2015-05-01
Full Text Available This paper presents the application of hybrid opposition based disruption operator in gravitational search algorithm (DOGSA to solve automatic generation control (AGC problem of four area hydro-thermal-gas interconnected power system. The proposed DOGSA approach combines the advantages of opposition based learning which enhances the speed of convergence and disruption operator which has the ability to further explore and exploit the search space of standard gravitational search algorithm (GSA. The addition of these two concepts to GSA increases its flexibility for solving the complex optimization problems. This paper addresses the design and performance analysis of DOGSA based proportional integral derivative (PID and fractional order proportional integral derivative (FOPID controllers for automatic generation control problem. The proposed approaches are demonstrated by comparing the results with the standard GSA, opposition learning based GSA (OGSA and disruption based GSA (DGSA. The sensitivity analysis is also carried out to study the robustness of DOGSA tuned controllers in order to accommodate variations in operating load conditions, tie-line synchronizing coefficient, time constants of governor and turbine. Further, the approaches are extended to a more realistic power system model by considering the physical constraints such as thermal turbine generation rate constraint, speed governor dead band and time delay.
Chen, Tinggui; Xiao, Renbin
2014-01-01
Due to fierce market competition, how to improve product quality and reduce development cost determines the core competitiveness of enterprises. However, design iteration generally causes increases of product cost and delays of development time as well, so how to identify and model couplings among tasks in product design and development has become an important issue for enterprises to settle. In this paper, the shortcomings existing in WTM model are discussed and tearing approach as well as inner iteration method is used to complement the classic WTM model. In addition, the ABC algorithm is also introduced to find out the optimal decoupling schemes. In this paper, firstly, tearing approach and inner iteration method are analyzed for solving coupled sets. Secondly, a hybrid iteration model combining these two technologies is set up. Thirdly, a high-performance swarm intelligence algorithm, artificial bee colony, is adopted to realize problem-solving. Finally, an engineering design of a chemical processing system is given in order to verify its reasonability and effectiveness.
Solution for Travelling Salesman Problem Based on Flowing Water Algorithm%基于流水算法的旅行商问题求解
Institute of Scientific and Technical Information of China (English)
王庆; 刘学鹏
2014-01-01
为了求解旅行商问题，本文借用“水无常形，水往低处流，水流千里归大海”的自然规律，提出新型元启发式求解算法：流水算法。新算法主要包括流水局部搜索、水漫溢出、流水凿洞、蒸发-下雨4个算子，同时具有禁忌搜索和正反馈机制特点，兼顾全局搜索和局部搜索能力。最后，本文应用MATLAB平台对算例进行仿真，并与其他经典的元启发式算法进行比较，结果表明流水算法是求解旅行商问题的有效方法，具有较好的收敛性。%To solve the travelling salesman problem, this paper proposes a novel meta-heuristics algorithm, called Flowing Water Algorithm, by borrowing the natural laws of “water has no unchanging shape”, “water flows downwards” and“water flows eventually into sea” and integrating the concept of self-adaptation and elite solution strategy. The new proposed FWA integrates mainly four operators including local search operator, overflowing operator, drilling water tunnel operator and evaporation-rain operator. This algorithm has global and local search capabilities as well as functions of tabu search and positive feedback. By simulating the cases based on MATLAB and analyzing the simulation results, this paper proves the effectiveness of FWA in the application of the travelling salesman problem. Besides, this novel algorithm has better convergence.
Hamiltonian Algorithm Sound Synthesis
大矢, 健一
2013-01-01
Hamiltonian Algorithm (HA) is an algorithm for searching solutions is optimization problems. This paper introduces a sound synthesis technique using Hamiltonian Algorithm and shows a simple example. "Hamiltonian Algorithm Sound Synthesis" uses phase transition effect in HA. Because of this transition effect, totally new waveforms are produced.
Chew, W. C.; Song, J. M.; Lu, C. C.; Weedon, W. H.
1995-01-01
In the first phase of our work, we have concentrated on laying the foundation to develop fast algorithms, including the use of recursive structure like the recursive aggregate interaction matrix algorithm (RAIMA), the nested equivalence principle algorithm (NEPAL), the ray-propagation fast multipole algorithm (RPFMA), and the multi-level fast multipole algorithm (MLFMA). We have also investigated the use of curvilinear patches to build a basic method of moments code where these acceleration techniques can be used later. In the second phase, which is mainly reported on here, we have concentrated on implementing three-dimensional NEPAL on a massively parallel machine, the Connection Machine CM-5, and have been able to obtain some 3D scattering results. In order to understand the parallelization of codes on the Connection Machine, we have also studied the parallelization of 3D finite-difference time-domain (FDTD) code with PML material absorbing boundary condition (ABC). We found that simple algorithms like the FDTD with material ABC can be parallelized very well allowing us to solve within a minute a problem of over a million nodes. In addition, we have studied the use of the fast multipole method and the ray-propagation fast multipole algorithm to expedite matrix-vector multiplication in a conjugate-gradient solution to integral equations of scattering. We find that these methods are faster than LU decomposition for one incident angle, but are slower than LU decomposition when many incident angles are needed as in the monostatic RCS calculations.
Salama, Amgad
2015-06-01
In this work, the experimenting fields approach is applied to the numerical solution of the Navier-Stokes equation for incompressible viscous flow. In this work, the solution is sought for both the pressure and velocity fields in the same time. Apparently, the correct velocity and pressure fields satisfy the governing equations and the boundary conditions. In this technique a set of predefined fields are introduced to the governing equations and the residues are calculated. The flow according to these fields will not satisfy the governing equations and the boundary conditions. However, the residues are used to construct the matrix of coefficients. Although, in this setup it seems trivial constructing the global matrix of coefficients, in other setups it can be quite involved. This technique separates the solver routine from the physics routines and therefore makes easy the coding and debugging procedures. We compare with few examples that demonstrate the capability of this technique.
Directory of Open Access Journals (Sweden)
Aminreza Noghrehabadi
2012-01-01
Full Text Available A hybrid power series and artificial bee colony algorithm (PS-ABC method is applied to solve a system of nonlinear differential equations arising from the distributed parameter model of multiwalled carbon nanotube (MWCNT cantilevers in the vicinity of thin and thick graphite sheets subject to intermolecular forces. The intermolecular forces are modeled using van der Waals forces. A trial solution of the differential equation is defined as sum of two polynomial parts. The first part satisfies the boundary conditions and does contain two adjustable parameters. The second part is constructed as not to affect the boundary conditions, which involves adjustable parameters. The ABC method is applied to find adjustable parameters of trial solution (in first and second part. The obtained results are compared with numerical results as well as analytical solutions those reported in the literature. The results of the presented method represent a remarkable accuracy in comparison with numerical results. The minimum initial gap and the detachment length of the actuator that does not stick to the substrate due to the intermolecular forces, as important parameters in pull-in instability of MWCNT actuator, are evaluated by obtained power series.
Multi-level significance of vulnerability indicators. Case study: Eastern Romania
Stanga, I. C.; Grozavu, A.
2012-04-01
Vulnerability assessment aims, most frequently, to emphasize internal fragility of a system comparing to a reference standard, to similar systems or in relation to a given hazard. Internal fragility, either biophysical or structural, may affect the capacity to predict, to prepare for, to cope with or to recover from a disaster. Thus, vulnerability is linked to resilience and adaptive capacity. From local level to global one, vulnerability factors and corresponding indicators are different and their significance must be tested and validated in a well-structured conceptual and methodological framework. In this paper, the authors aim to show the real vulnerability of rural settlements in Eastern Romania in a multi-level approach. The research area, Tutova Hills, counts about 3421 sq.km and more than 200.000 inhabitants in 421 villages characterized by deficient accessibility, lack of endowments, subsistential agriculture, high pressure on natural environment (especially on forest and soil resources), poverty and aging process of population. Factors that could influence the vulnerability of these rural settlements have been inventoried and assigned into groups through a cluster analysis: habitat and technical urban facilities, infrastructure, economical, social and demographical indicators, environment quality, management of emergency situations etc. Firstly, the main difficulty was to convert qualitative variable in quantitative indicators and to standardize all values to make possible mathematical and statistical processing of data. Secondly, the great variability of vulnerability factors, their different measuring units and their high amplitude of variation require different method of standardization in order to obtain values between zero (minimum vulnerability) and one (maximum vulnerability). Final vulnerability indicators were selected and integrated in a general scheme, according to their significance resulted from an appropriate factor analysis: linear and
RNA-Seq and molecular docking reveal multi-level pesticide resistance in the bed bug
Directory of Open Access Journals (Sweden)
Mamidala Praveen
2012-01-01
Full Text Available Abstract Background Bed bugs (Cimex lectularius are hematophagous nocturnal parasites of humans that have attained high impact status due to their worldwide resurgence. The sudden and rampant resurgence of C. lectularius has been attributed to numerous factors including frequent international travel, narrower pest management practices, and insecticide resistance. Results We performed a next-generation RNA sequencing (RNA-Seq experiment to find differentially expressed genes between pesticide-resistant (PR and pesticide-susceptible (PS strains of C. lectularius. A reference transcriptome database of 51,492 expressed sequence tags (ESTs was created by combining the databases derived from de novo assembled mRNA-Seq tags (30,404 ESTs and our previous 454 pyrosequenced database (21,088 ESTs. The two-way GLMseq analysis revealed ~15,000 highly significant differentially expressed ESTs between the PR and PS strains. Among the top 5,000 differentially expressed ESTs, 109 putative defense genes (cuticular proteins, cytochrome P450s, antioxidant genes, ABC transporters, glutathione S-transferases, carboxylesterases and acetyl cholinesterase involved in penetration resistance and metabolic resistance were identified. Tissue and development-specific expression of P450 CYP3 clan members showed high mRNA levels in the cuticle, Malpighian tubules, and midgut; and in early instar nymphs, respectively. Lastly, molecular modeling and docking of a candidate cytochrome P450 (CYP397A1V2 revealed the flexibility of the deduced protein to metabolize a broad range of insecticide substrates including DDT, deltamethrin, permethrin, and imidacloprid. Conclusions We developed significant molecular resources for C. lectularius putatively involved in metabolic resistance as well as those participating in other modes of insecticide resistance. RNA-Seq profiles of PR strains combined with tissue-specific profiles and molecular docking revealed multi-level insecticide
Change of cervical balance following single to multi-level interbody fusion with cage.
Lin, Hung-Lin; Cho, Der-Yang; Liu, Yu-Fang; Lee, Wen-Yuan; Lee, Han-Chung; Chen, Chun-Chung
2008-12-01
Postoperative limitation of cervical movement and adjacent disc degeneration are major causes of postoperative neck pain after anterior cervical discectomy and interbody fusion (ACDF). We present a retrospective study of dynamic radiographic change following ACDF with cages. We performed ACDF in 50 patients with cervical degenerative diseases, divided into three groups based on the level of interbody fusion (Group A: one-level; Group B: two-level; Group C: three-level). Preoperative and postoperative flexion-extension X-rays were acquired and cervical range of motion (ROM), lordosis, fusion rate, cage subsidence rate, postoperative neck pain as evaluated by visual analogue scale (VAS) and upper adjacent level segmental movement were evaluated. The average following time was 14.6 months. The mean change in lordotic curve was -2.31 +/- 9.53 degrees for Group A, 5.60 +/- 6.96 degrees for Group B, and 3.23 +/- 7.50 degrees for Group C (p value = 0.03). The mean change in flexion angle was -5.46 +/- 8.69 degrees for Group A, -10.2 +/- 7.38 degrees for Group B, and -13.86 +/- 10.33 degrees for Group C (p value = 0.039). The mean change in total cervical ROM was -3.85 +/- 18.74 degrees for Group A, -12.73 +/- 10.31 degrees for Group B, and -16.95 +/- 10.57 degrees for Group C (p value = 0.02). Follow-up cervical MRI for patients with persistent neck pain showed no evidence of adjacent level degeneration. There were no significant differences between the three groups with respect to postoperative change in cervical extension angle, upper adjacent level segmental movement, neck pain VAS, fusion rate or cage subsidence rate. The further decrease in total cervical ROM and flexion movement after multi-level ACDF was observed. However, a more long-term follow-up was needed to assess the actual aetiologies of upper adjacent level degeneration.
Web搜索结果多层聚类方法研究%Research on Multi-level Clustering for Web Search Results
Institute of Scientific and Technical Information of China (English)
庞观松; 蒋盛益; 张黎莎; 区雄发; 赖旭明
2011-01-01
In order to facilitate the browse of the search results produced by search engines, this paper proposed a TFIDF-based new mechod to calculate the similarity of the documents and Web search results multi-level clustering by using one-pass clustering algorithm with linear time complexity. At the same time, we proposed a strategy to extract cluster keyword from multi-texts: selected noun or noun phrase as candidate cluster keywords, and took term frequency, the position of term occurring, the length of term and text into consideration to set a weighting function to compute every words weights of the search results, then automatically extracted the weightiest candidate keyword for each cluster generated by multi-level clustering without the intervene of human and the assistance of corpus. Experimental results on Baidu, ODP corpus and user investigation show the efficient and acceptance of our algorithm.%为了便于用户浏览搜索引擎返回结果,本文提出了一种基于TFIDF新的文本相似度计算方法,并提出使用具有近似线性时间复杂度的增量聚类算法对文本进行多层聚类的策略.同时,提出了一种从多文本中提取关键词的策略:提取簇中的名词或名词短语作为候选关键词,综合考虑每个候选关键词的词频、出现位置、长度和文本长度设置加权函数来计算其权重,不需要人工干预以及语料库的协助,自动提取权重最大的候选关键词作为类别关键词.在收集的百度、ODP语料以及公开测试的实验结果表明本文提出方法的有效性.
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Eusebio Eduardo Hernández Martinez
2013-01-01
Full Text Available In robotics, solving the direct kinematics problem (DKP for parallel robots is very often more difficult and time consuming than for their serial counterparts. The problem is stated as follows: given the joint variables, the Cartesian variables should be computed, namely the pose of the mobile platform. Most of the time, the DKP requires solving a non‐linear system of equations. In addition, given that the system could be non‐convex, Newton or Quasi‐Newton (Dogleg based solvers get trapped on local minima. The capacity of such kinds of solvers to find an adequate solution strongly depends on the starting point. A well‐known problem is the selection of such a starting point, which requires a priori information about the neighbouring region of the solution. In order to circumvent this issue, this article proposes an efficient method to select and to generate the starting point based on probabilistic learning. Experiments and discussion are presented to show the method performance. The method successfully avoids getting trapped on local minima without the need for human intervention, which increases its robustness when compared with a single Dogleg approach. This proposal can be extended to other structures, to any non‐linear system of equations, and of course, to non‐linear optimization problems.
Energy Technology Data Exchange (ETDEWEB)
Siqueira, A. F. de, E-mail: siqueiraaf@gmail.com; Cabrera, F. C., E-mail: flavioccabrera@yahoo.com.br [UNESP – Univ Estadual Paulista, Dep de Física, Química e Biologia (Brazil); Pagamisse, A., E-mail: aylton@fct.unesp.br [UNESP – Univ Estadual Paulista, Dep de Matemática e Computação (Brazil); Job, A. E., E-mail: job@fct.unesp.br [UNESP – Univ Estadual Paulista, Dep de Física, Química e Biologia (Brazil)
2014-12-15
This study consolidates multi-level starlet segmentation (MLSS) and multi-level starlet optimal segmentation (MLSOS) techniques for photomicrograph segmentation, based on starlet wavelet detail levels to separate areas of interest in an input image. Several segmentation levels can be obtained using MLSS; after that, Matthews correlation coefficient is used to choose an optimal segmentation level, giving rise to MLSOS. In this paper, MLSOS is employed to estimate the concentration of gold nanoparticles with diameter around 47 nm, reduced on natural rubber membranes. These samples were used for the construction of SERS/SERRS substrates and in the study of the influence of natural rubber membranes with incorporated gold nanoparticles on the physiology of Leishmania braziliensis. Precision, recall, and accuracy are used to evaluate the segmentation performance, and MLSOS presents an accuracy greater than 88 % for this application.
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Yu Qi
2017-03-01
Full Text Available The biological performance of artificial biomaterials is closely related to their structure characteristics. Cell adhesion, migration, proliferation, and differentiation are all strongly affected by the different scale structures of biomaterials. Silk fibroin (SF, extracted mainly from silkworms, has become a popular biomaterial due to its excellent biocompatibility, exceptional mechanical properties, tunable degradation, ease of processing, and sufficient supply. As a material with excellent processability, SF can be processed into various forms with different structures, including particulate, fiber, film, and three-dimensional (3D porous scaffolds. This review discusses and summarizes the various constructions of SF-based materials, from single structures to multi-level structures, and their applications. In combination with single structures, new techniques for creating special multi-level structures of SF-based materials, such as micropatterning and 3D-printing, are also briefly addressed.
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Mark Scully
2010-04-01
Full Text Available We demonstrate an automated, multi-level method to segment white matter brain lesions and apply it to lupus. The method makes use of local morphometric features based on multiple MR sequences, including T1-weighted, T2-weighted, and Fluid Attenuated Inversion Recovery. After preprocessing, including co-registration, brain extraction, bias correction, and intensity standardization, 49 features are calculated for each brain voxel based on local morphometry. At each level of segmentation a supervised classifier takes advantage of a different subset of the features to conservatively segment lesion voxels, passing on more difficult voxels to the next classifier. This multi-level approach allows for a fast lesion classification method with tunable trade-offs between sensitivity and specificity producing accuracy comparable to a human rater.
Qi, Yu; Wang, Hui; Wei, Kai; Yang, Ya; Zheng, Ru-Yue; Kim, Ick Soo; Zhang, Ke-Qin
2017-01-01
The biological performance of artificial biomaterials is closely related to their structure characteristics. Cell adhesion, migration, proliferation, and differentiation are all strongly affected by the different scale structures of biomaterials. Silk fibroin (SF), extracted mainly from silkworms, has become a popular biomaterial due to its excellent biocompatibility, exceptional mechanical properties, tunable degradation, ease of processing, and sufficient supply. As a material with excellent processability, SF can be processed into various forms with different structures, including particulate, fiber, film, and three-dimensional (3D) porous scaffolds. This review discusses and summarizes the various constructions of SF-based materials, from single structures to multi-level structures, and their applications. In combination with single structures, new techniques for creating special multi-level structures of SF-based materials, such as micropatterning and 3D-printing, are also briefly addressed. PMID:28273799
Paduszyński, Kamil
2016-08-22
The aim of the paper is to address all the disadvantages of currently available models for calculating infinite dilution activity coefficients (γ(∞)) of molecular solutes in ionic liquids (ILs)-a relevant property from the point of view of many applications of ILs, particularly in separations. Three new models are proposed, each of them based on distinct machine learning algorithm: stepwise multiple linear regression (SWMLR), feed-forward artificial neural network (FFANN), and least-squares support vector machine (LSSVM). The models were established based on the most comprehensive γ(∞) data bank reported so far (>34 000 data points for 188 ILs and 128 solutes). Following the paper published previously [J. Chem. Inf. Model 2014, 54, 1311-1324], the ILs were treated in terms of group contributions, whereas the Abraham solvation parameters were used to quantify an impact of solute structure. Temperature is also included in the input data of the models so that they can be utilized to obtain temperature-dependent data and thus related thermodynamic functions. Both internal and external validation techniques were applied to assess the statistical significance and explanatory power of the final correlations. A comparative study of the overall performance of the investigated SWMLR/FFANN/LSSVM approaches is presented in terms of root-mean-square error and average absolute relative deviation between calculated and experimental γ(∞), evaluated for different families of ILs and solutes, as well as between calculated and experimental infinite dilution selectivity for separation problems benzene from n-hexane and thiophene from n-heptane. LSSVM is shown to be a method with the lowest values of both training and generalization errors. It is finally demonstrated that the established models exhibit an improved accuracy compared to the state-of-the-art model, namely, temperature-dependent group contribution linear solvation energy relationship, published in 2011 [J. Chem
Minimizing End-to-End Interference in I/O Stacks Spanning Shared Multi-Level Buffer Caches
Patrick, Christina M.
2011-01-01
This thesis presents an end-to-end interference minimizing uniquely designed high performance I/O stack that spans multi-level shared buffer cache hierarchies accessing shared I/O servers to deliver a seamless high performance I/O stack. In this thesis, I show that I can build a superior I/O stack which minimizes the inter-application interference…
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Natalia Torres Zúñiga
2013-12-01
Full Text Available This article addresses diverse perspectives concerning relationship between reviewing (laws for compliance and the process of putting international law of human rights on a constitutional footing. Therefore, a parallel is established between reviewing (laws for compliance and constitutional review (laws in order to outline features and application impact of this research. The design of a multi-level protection system for fundamental rights in Latin America is also discussed in this article.
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Jianqiang Mo
Full Text Available For multi-level spondylolysis patients, surgeons commonly choose to fix all the segments with pars interarticularis defect even those without slippage and not responsible for clinical symptoms. In this study, we tried to study the necessity of the preventative long-segment surgery for the defected segment without slippage in treatment of multi-level spondylolysis patients from a biomechanical perspective.We established a bi-level spondylolysis model with pars defects at L4 and L5 segments, and simulated posterior lumbar interbody fusion (PLIF and pedicle screw fixation at L5-S1 level. Then we compared the biomechanical changes at L4 segment before and after surgery in neutral, flexion, extension, lateral bending and axial rotation position.The stress on L4 pars interarticularis was very similar before and after surgery, and reached the highest in axial rotation. The L3-L4 intradiscal pressure was almost the same, while L4-L5 intradiscal pressure changed a little in lateral bending (increase from 1.993 to 2.160 MPa and axial rotation (decrease from 1.639 to 1.307 MPa after surgery. The PLIF surgery caused a little increase of range of motion at adjacent L4-L5 and L3-L4 levels, but the change is very tiny (1 degree.The PLIF surgery will not cause significant biomechanical change at adjacent segment with pars defect in multi-level spondylolysis. On the contrary, excessive long-segment surgery will damage surrounding soft tissues which are important for maintaining the stability of spine. So a preventative long-segment surgery is not necessary for multi-level spondylolysis as long as there are no soft tissue degeneration signs at adjacent level.
Witt, Michael; Krefting, Dagmar
2016-01-01
Human sample data is stored in biobanks with software managing digital derived sample data. When these stand-alone components are connected and a search infrastructure is employed users become able to collect required research data from different data sources. Data protection, patient rights, data heterogeneity and access control are major challenges for such an infrastructure. This dissertation will investigate concepts for a multi-level security architecture to comply with these requirements.
Minimizing End-to-End Interference in I/O Stacks Spanning Shared Multi-Level Buffer Caches
Patrick, Christina M.
2011-01-01
This thesis presents an end-to-end interference minimizing uniquely designed high performance I/O stack that spans multi-level shared buffer cache hierarchies accessing shared I/O servers to deliver a seamless high performance I/O stack. In this thesis, I show that I can build a superior I/O stack which minimizes the inter-application interference…
Kim, Woo-Keun; Jung, Jinho
2016-06-01
The integration of biomarker responses ranging from the molecular to the individual level is of great interest for measuring the toxic effects of hazardous chemicals or effluent mixtures on aquatic organisms. This study evaluated the effects of wastewater treatment plant (WWTP) effluents on the freshwater pale chub Zacco platypus by using multi-level biomarker responses at molecular [mRNA expression of catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), and metallothionein (MT)], biochemical (enzyme activities of CAT, SOD, GST, and concentration of MT), and physiological [condition factor (CF) and liver somatic index (LSI)] levels. The mRNA expression levels of GST and MT in Z. platypus from a site downstream of a WWTP significantly increased by 2.2- and 4.5-fold (penzyme activities of CAT, SOD, and GST in fish from the downstream site significantly decreased by 43%, 98%, and 13%, respectively (p<0.05), except for an increase in MT concentration (41%). In addition, a significant increase in LSI (46%) was observed in Z. platypus from the downstream site (p<0.05). Concentrations of Cu, Zn, Cd, and Pb in the liver of Z. platypus were higher (530%, 353%, 800%, and 2,200%, respectively) in fish from a downstream site than in fish from an upstream location, and several multi-level biomarker responses were significantly correlated with the accumulated metals in Z. platypus (p<0.05). Integrated biomarker responses at molecular, biochemical, and physiological levels (multi-level IBR) were much higher (about 4-fold) at the downstream site than at the upstream site. This study suggests that the multi-level IBR approach is very useful for quantifying in situ adverse effects of WWTP effluents.
De Vos, Jaqueline
2012-01-01
Workplace bullying is recognised as a major psychosocial stressor in various professions and can have severe effects on health. Teachers are distinguished as an occupational group that is severely affected by this phenomenon. The general objectives of this research study were to firstly investigate teachers’ experiences of workplace bullying and its effects on health, and secondly, to develop a multi-level intervention programme that can be implemented to address workplace bullying and its ef...
Almer, Alexander; Schnabel, Thomas; Perko, Roland; Raggam, Johann; Köfler, Armin; Feischl, Richard
2016-04-01
-fighting missions. The ongoing development focuses on the following topics: (1) Development of a multi-level management solution to coordinate and guide different airborne and terrestrial deployed firefighting modules as well as related data processing and data distribution activities. (2) Further, a targeted control of the thermal sensor based on a rotating mirror system to extend the "area performance" (covered area per hour) in time critical situations for the monitoring requirements during forest fire events. (3) Novel computer vision methods for analysis of thermal sensor signatures, which allow an automatic classification of different forest fire types and situations. (4) A module for simulation-based decision support for planning and evaluation of resource usage and the effectiveness of performed fire-fighting measures. (5) Integration of wearable systems to assist ground teams in rescue operations as well as a mobile information system into innovative command and fire-fighting vehicles. In addition, the paper gives an outlook on future perspectives including a first concept for the integration of the near real-time multilevel forest fire fighting management system into an "EU Civil Protection Team" to support the EU civil protection modules and the Emergency Response Coordination Centre in Brussels. Keywords: Airborne sensing, multi sensor imaging, near real-time fire monitoring, simulation-based decision support, forest firefighting management, firefighting impact analysis.
Kode, Swathi; Kallemeyn, Nicole A; Smucker, Joseph D; Fredericks, Douglas C; Grosland, Nicole M
2014-01-01
Laminectomy has been regarded as a standard treatment for multi-level cervical stenosis. Concern for complications such as kyphosis has limited the indication of multi-level laminectomy; hence it is often augmented with an instrumented fusion. Laminoplasty has emerged as a motion preserving alternative. The purpose of this study was to compare the multidirectional flexibility of the cervical spine in response to a plate-only open door laminoplasty, double door laminoplasty, and laminectomy using a computational model. A validated three-dimensional finite element model of a specimen-specific intact cervical spine (C2-T1) was modified to simulate each surgical procedure at levels C3-C6. An additional goal of this work was to compare the instrumented computational model to our multi-specimen experimental findings to ensure similar trends in response to the surgical procedures. Model predictions indicate that mobility was retained following open and double door laminoplasty with a 5.4% and 20% increase in flexion, respectively, compared to the intact state. Laminectomy resulted in 57% increase in flexion as compared to the intact state, creating a concern for eventual kyphosis--a known risk/complication of multi-level laminectomy in the absence of fusion. Increased disc stresses were observed at the altered and adjacent segments post-laminectomy in flexion.
Multi-Level Reduced Order Modeling Equipped with Probabilistic Error Bounds
Abdo, Mohammad Gamal Mohammad Mostafa
This thesis develops robust reduced order modeling (ROM) techniques to achieve the needed efficiency to render feasible the use of high fidelity tools for routine engineering analyses. Markedly different from the state-of-the-art ROM techniques, our work focuses only on techniques which can quantify the credibility of the reduction which can be measured with the reduction errors upper-bounded for the envisaged range of ROM model application. Our objective is two-fold. First, further developments of ROM techniques are proposed when conventional ROM techniques are too taxing to be computationally practical. This is achieved via a multi-level ROM methodology designed to take advantage of the multi-scale modeling strategy typically employed for computationally taxing models such as those associated with the modeling of nuclear reactor behavior. Second, the discrepancies between the original model and ROM model predictions over the full range of model application conditions are upper-bounded in a probabilistic sense with high probability. ROM techniques may be classified into two broad categories: surrogate construction techniques and dimensionality reduction techniques, with the latter being the primary focus of this work. We focus on dimensionality reduction, because it offers a rigorous approach by which reduction errors can be quantified via upper-bounds that are met in a probabilistic sense. Surrogate techniques typically rely on fitting a parametric model form to the original model at a number of training points, with the residual of the fit taken as a measure of the prediction accuracy of the surrogate. This approach, however, does not generally guarantee that the surrogate model predictions at points not included in the training process will be bound by the error estimated from the fitting residual. Dimensionality reduction techniques however employ a different philosophy to render the reduction, wherein randomized snapshots of the model variables, such as the
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Jantien Stoter
2017-05-01
Full Text Available This article reports on the first 3D cadastral registration in The Netherlands, accomplished in March 2016. The solution was sought within the current cadastral, organisational, and technical frameworks to obtain a deeper knowledge on the optimal way of implementing 3D registration, while avoiding discussions between experts from different domains. The article presents the developed methodology to represent legal volumes in an interactive 3D visualisation that can be registered in the land registers. The source data is the 3D Building Information Model (BIM. The methodology is applied to two cases: (1 the case of the railway station in Delft, resulting in the actual 3D registration in 2016; and (2 a building complex in Amsterdam, improving the Delft-case and providing the possibility to describe a general workflow from design data to a legal document. An evaluation provides insights for an improved cadastral registration of multi-level property rights. The main conclusion is that in specific situations, a 3D approach has important advantages for cadastral registration over a 2D approach. Further study is needed to implement the solution in a standardised and uniform way, from registration to querying and updating in the future, and to develop a formal registration process accordingly.
Decherchi, Sergio; Colmenares, José; Catalano, Chiara Eva; Spagnuolo, Michela; Alexov, Emil; Rocchia, Walter
2013-01-01
The definition of a molecular surface which is physically sound and computationally efficient is a very interesting and long standing problem in the implicit solvent continuum modeling of biomolecular systems as well as in the molecular graphics field. In this work, two molecular surfaces are evaluated with respect to their suitability for electrostatic computation as alternatives to the widely used Connolly-Richards surface: the blobby surface, an implicit Gaussian atom centered surface, and the skin surface. As figures of merit, we considered surface differentiability and surface area continuity with respect to atom positions, and the agreement with explicit solvent simulations. Geometric analysis seems to privilege the skin to the blobby surface, and points to an unexpected relationship between the non connectedness of the surface, caused by interstices in the solute volume, and the surface area dependence on atomic centers. In order to assess the ability to reproduce explicit solvent results, specific software tools have been developed to enable the use of the skin surface in Poisson-Boltzmann calculations with the DelPhi solver. Results indicate that the skin and Connolly surfaces have a comparable performance from this last point of view.
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Gh. Assadipour
2012-01-01
Full Text Available
ENGLISH ABSTRACT:The trade-off between time, cost, and quality is one of the important problems of project management. This problem assumes that all project activities can be executed in different modes of cost, time, and quality. Thus a manager should select each activity’s mode such that the project can meet the deadline with the minimum possible cost and the maximum achievable quality. As the problem is NP-hard and the objectives are in conflict with each other, a multi-objective meta-heuristic called CellDE, which is a hybrid cellular genetic algorithm, is implemented as the optimisation method. The proposed algorithm provides project managers with a set of non-dominated or Pareto-optimal solutions, and enables them to choose the best one according to their preferences. A set of problems of different sizes is generated and solved using the proposed algorithm. Three metrics are employed for evaluating the performance of the algorithm, appraising the diversity and convergence of the achieved Pareto fronts. Finally a comparison is made between CellDE and another meta-heuristic available in the literature. The results show the superiority of CellDE.
AFRIKAANSE OPSOMMING: ‘n Balans tussen tyd, koste en gehalte is een van die belangrike probleme van projekbestuur. Die vraagstuk maak gewoonlik die aanname dat alle projekaktiwiteite uitgevoer kan word op uiteenlopende wyses wat verband hou met koste, tyd en gehalte. ‘n Projekbestuurder selekteer gewoonlik die uitvoeringsmetodes sodanig per aktiwiteit dat gehoor gegegee word aan minimum koste en maksimum gehalte teen die voorwaarde van voltooiingsdatum wat bereik moet word.
Aangesien die beskrewe problem NP-hard is, word dit behandel ten opsigte van konflikterende doelwitte met ‘n multidoelwit metaheuristiese metode (CellDE. Die metode is ‘n hibride-sellulêre genetiese algoritme. Die algoritme lewer aan die besluitvormer ‘n versameling van ongedomineerde of Pareto