Roles of Working Memory Performance and Instructional Strategy in Complex Cognitive Task Performance

Science.gov (United States)

Cevik, V.; Altun, A.

2016-01-01

This study aims to investigate how working memory (WM) performances and instructional strategy choices affect learners' complex cognitive task performance in online environments. Three different e-learning environments were designed based on Merrill's (2006a) model of instructional strategies. The lack of experimental research on his framework is…

Joining Distributed Complex Objects: Definition and Performance

NARCIS (Netherlands)

Teeuw, W.B.; Teeuw, Wouter B.; Blanken, Henk

1992-01-01

The performance of a non-standard distributed database system is strongly ifluenced by complex objects. The effective exploitation of parallelism in querying them and a suitable structure to store them are required in order to obtain acceptable response times in these database environments where

Procurement of complex performance in public infrastructure: a process perspective

OpenAIRE

Hartmann, Andreas; Roehrich, Jens; Davies, Andrew; Frederiksen, Lars; Davies, J.; Harrington, T.; Kirkwood, D.; Holweg, M.

2011-01-01

The paper analyzes the process of transitioning from procuring single products and services to procuring complex performance in public infrastructure. The aim is to examine the change in the interactions between buyer and supplier, the emergence of value co-creation and the capability development during the transition process. Based on a multiple, longitudinal case study the paper proposes three generic transition stages towards increased performance and infrastructural complexity. These stag...

Does complexity matter? Meta-analysis of learner performance in artificial grammar tasks.

Science.gov (United States)

Schiff, Rachel; Katan, Pesia

2014-01-01

Complexity has been shown to affect performance on artificial grammar learning (AGL) tasks (categorization of test items as grammatical/ungrammatical according to the implicitly trained grammar rules). However, previously published AGL experiments did not utilize consistent measures to investigate the comprehensive effect of grammar complexity on task performance. The present study focused on computerizing Bollt and Jones's (2000) technique of calculating topological entropy (TE), a quantitative measure of AGL charts' complexity, with the aim of examining associations between grammar systems' TE and learners' AGL task performance. We surveyed the literature and identified 56 previous AGL experiments based on 10 different grammars that met the sampling criteria. Using the automated matrix-lift-action method, we assigned a TE value for each of these 10 previously used AGL systems and examined its correlation with learners' task performance. The meta-regression analysis showed a significant correlation, demonstrating that the complexity effect transcended the different settings and conditions in which the categorization task was performed. The results reinforced the importance of using this new automated tool to uniformly measure grammar systems' complexity when experimenting with and evaluating the findings of AGL studies.

Complexities and constraints influencing learner performance in physical science

Directory of Open Access Journals (Sweden)

Mavhungu Abel Mafukata

2016-01-01

Full Text Available This paper explores complexities and constraints affecting performance and output of physical science learners in Vhembe District, Limpopo Province, South Africa. The study was motivated by the desire of the researcher to establish, profile and characterise the complexities and constraints reminiscence of poor performance of learners in physical science as measured through end-of-year Grade 12 (final year of high school education examination results. Twenty six schools (n=26 were purposively selected from three circuits of education (n=3. From these schools, two learners were randomly selected (n=52 for interviews. In addition, two circuit managers (n=2 were conveniently selected as part of Key Informant Interviews (KII. For the Focus Group Discussions (FGDs, twelve (n=12 parents were randomly selected to form two groups of six members each. Multi-factor complexities and constraints impeding performance of learners were discovered. Intensive teacher in-service programme is recommended. Community engagement should be encouraged to educate parents on the value of involvement in the education of their children. Free access learner support structures such as Homework and Extra-lessons Assistance Centre (H&EACs should be established.

Cooperative decoding in femtocell networks: Performance-complexity tradeoff

KAUST Repository

Benkhelifa, Fatma

2012-06-01

Femtocells, which are low cost low power, stand alone cellular access points, are a potential solution to provide good indoor coverage with high data rate. However, the femtocell deployment may also increase the co-channel interference (CCI) by reducing the distance reuse of the spectrum. In this paper, we introduce methods to cancel out the interference among the femtocells while considering that macrocells operate orthogonally to the femtocells. The femtocells may also cooperate through joint detection of the received signal and improve the overall error performance at the expense of an increased computational complexity. In this paper, the performance-complexity tradeoff of cooperative detection is investigated for uplink transmissions. Numerical results show that the cooperative detection gain may reach 10 dB at a Bit-Error Rate (BER) of 10 -2 when compared to the case without cooperation. © 2012 IEEE.

Cooperative decoding in femtocell networks: Performance-complexity tradeoff

KAUST Repository

Benkhelifa, Fatma; Rezki, Zouheir; Alouini, Mohamed-Slim

2012-01-01

Femtocells, which are low cost low power, stand alone cellular access points, are a potential solution to provide good indoor coverage with high data rate. However, the femtocell deployment may also increase the co-channel interference (CCI) by reducing the distance reuse of the spectrum. In this paper, we introduce methods to cancel out the interference among the femtocells while considering that macrocells operate orthogonally to the femtocells. The femtocells may also cooperate through joint detection of the received signal and improve the overall error performance at the expense of an increased computational complexity. In this paper, the performance-complexity tradeoff of cooperative detection is investigated for uplink transmissions. Numerical results show that the cooperative detection gain may reach 10 dB at a Bit-Error Rate (BER) of 10 -2 when compared to the case without cooperation. © 2012 IEEE.

Complex matrix multiplication operations with data pre-conditioning in a high performance computing architecture

Science.gov (United States)

Eichenberger, Alexandre E; Gschwind, Michael K; Gunnels, John A

2014-02-11

Mechanisms for performing a complex matrix multiplication operation are provided. A vector load operation is performed to load a first vector operand of the complex matrix multiplication operation to a first target vector register. The first vector operand comprises a real and imaginary part of a first complex vector value. A complex load and splat operation is performed to load a second complex vector value of a second vector operand and replicate the second complex vector value within a second target vector register. The second complex vector value has a real and imaginary part. A cross multiply add operation is performed on elements of the first target vector register and elements of the second target vector register to generate a partial product of the complex matrix multiplication operation. The partial product is accumulated with other partial products and a resulting accumulated partial product is stored in a result vector register.

42 CFR 493.1453 - Condition: Laboratories performing high complexity testing; clinical consultant.

Science.gov (United States)

2010-10-01

... Condition: Laboratories performing high complexity testing; clinical consultant. The laboratory must have a... 42 Public Health 5 2010-10-01 2010-10-01 false Condition: Laboratories performing high complexity testing; clinical consultant. 493.1453 Section 493.1453 Public Health CENTERS FOR MEDICARE & MEDICAID...

Product variety, product complexity and manufacturing operational performance: A systematic literature review

DEFF Research Database (Denmark)

Trattner, Alexandria Lee; Hvam, Lars; Herbert-Hansen, Zaza Nadja Lee

Manufacturing in the twenty-first century has been wrought with the struggle to satisfy the rising demand for greater product variety and more complex products while still maintaining efficient manufacturing operations. However, the literature lacks an overview of which operational performance...... measures are most affected by increased variety and complexity. This study presents a systematic literature review of the recent scholarly literature on variety, complexity and manufacturing operational performance (MOP). Results show that product variety has a consistently negative relationship with MOP...... across different time, cost, quality and flexibility measures while product complexity lacks evidence of strong relationships with MOP measures....

The Role of Task Complexity, Modality, and Aptitude in Narrative Task Performance

Science.gov (United States)

Kormos, Judit; Trebits, Anna

2012-01-01

The study reported in this paper investigated the relationship between components of aptitude and the fluency, lexical variety, syntactic complexity, and accuracy of performance in two types of written and spoken narrative tasks. We also addressed the question of how narrative performance varies in tasks of different cognitive complexity in the…

Radioactive Waste Management Complex performance assessment: Draft

Energy Technology Data Exchange (ETDEWEB)

Case, M.J.; Maheras, S.J.; McKenzie-Carter, M.A.; Sussman, M.E.; Voilleque, P.

1990-06-01

A radiological performance assessment of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory was conducted to demonstrate compliance with appropriate radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the general public. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the general public via air, ground water, and food chain pathways. Projections of doses were made for both offsite receptors and individuals intruding onto the site after closure. In addition, uncertainty analyses were performed. Results of calculations made using nominal data indicate that the radiological doses will be below appropriate radiological criteria throughout operations and after closure of the facility. Recommendations were made for future performance assessment calculations.

Radioactive Waste Management Complex performance assessment: Draft

International Nuclear Information System (INIS)

Case, M.J.; Maheras, S.J.; McKenzie-Carter, M.A.; Sussman, M.E.; Voilleque, P.

1990-06-01

A radiological performance assessment of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory was conducted to demonstrate compliance with appropriate radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the general public. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the general public via air, ground water, and food chain pathways. Projections of doses were made for both offsite receptors and individuals intruding onto the site after closure. In addition, uncertainty analyses were performed. Results of calculations made using nominal data indicate that the radiological doses will be below appropriate radiological criteria throughout operations and after closure of the facility. Recommendations were made for future performance assessment calculations

Procuring complex performance:case: public infrastructure projects

OpenAIRE

Leppänen, T. (Tero)

2015-01-01

Abstract This research studies procuring complex performance (PCP) in the case of public infrastructure projects. Focus of the research is on the interface between public clients and private sector contractors. Purpose of this research is to find out what are the main challenges of different project delivery methods according to literature (RQ1) and what are the practical challenges of public procurement (RQ2). As an end re...

Performances and improvement of copper-hydrazine complexation deoxidising resin

International Nuclear Information System (INIS)

Liu Fenfen; Zhang Hao; Sun Haijun; Liu Xiaojie

2012-01-01

Copper-hydrazine complexation deoxidising resin is tested to examine its performances including effluent water quality and capacity of deoxidisation. By the means of changing the resin type and regeneration, the deoxidising capacity of the resin can be improved to 13 times more than before. At the same time, physical performances of the resin are also greatly improved while maintaining its velocity of deoxidisation and effluent quality. (authors)

High performance parallel computing of flows in complex geometries: II. Applications

International Nuclear Information System (INIS)

Gourdain, N; Gicquel, L; Staffelbach, G; Vermorel, O; Duchaine, F; Boussuge, J-F; Poinsot, T

2009-01-01

Present regulations in terms of pollutant emissions, noise and economical constraints, require new approaches and designs in the fields of energy supply and transportation. It is now well established that the next breakthrough will come from a better understanding of unsteady flow effects and by considering the entire system and not only isolated components. However, these aspects are still not well taken into account by the numerical approaches or understood whatever the design stage considered. The main challenge is essentially due to the computational requirements inferred by such complex systems if it is to be simulated by use of supercomputers. This paper shows how new challenges can be addressed by using parallel computing platforms for distinct elements of a more complex systems as encountered in aeronautical applications. Based on numerical simulations performed with modern aerodynamic and reactive flow solvers, this work underlines the interest of high-performance computing for solving flow in complex industrial configurations such as aircrafts, combustion chambers and turbomachines. Performance indicators related to parallel computing efficiency are presented, showing that establishing fair criterions is a difficult task for complex industrial applications. Examples of numerical simulations performed in industrial systems are also described with a particular interest for the computational time and the potential design improvements obtained with high-fidelity and multi-physics computing methods. These simulations use either unsteady Reynolds-averaged Navier-Stokes methods or large eddy simulation and deal with turbulent unsteady flows, such as coupled flow phenomena (thermo-acoustic instabilities, buffet, etc). Some examples of the difficulties with grid generation and data analysis are also presented when dealing with these complex industrial applications.

Performance in complex motor tasks deteriorates in hyperthermic humans

DEFF Research Database (Denmark)

Piil, Jacob Feder; Lundbye-Jensen, Jesper; Trangmar, Steven J

2017-01-01

-motor tracking performance was reduced by 10.7 ± 6.5% following exercise-induced hyperthermia when integrated in the multipart protocol and 4.4 ± 5.7% when tested separately (bothP 1.3% (P math tasks...... of information or decision-making prior to responding. We hypothesized that divergences could relate to task complexity and developed a protocol consisting of 1) simple motor task [TARGET_pinch], 2) complex motor task [Visuo-motor tracking], 3) simple math task [MATH_type], 4) combined motor-math task [MATH...

Complex Hand Dexterity: A Review of Biomechanical Methods for Measuring Musical Performance

Directory of Open Access Journals (Sweden)

Cheryl Diane Metcalf

2014-05-01

Full Text Available Complex hand dexterity is fundamental to our interactions with the physical, social and cultural environment. Dexterity can be an expression of creativity and precision in a range of activities, including musical performance. Little is understood about complex hand dexterity or how virtuoso expertise is acquired, due to the versatility of movement combinations available to complete any given task. This has historically limited progress of the field because of difficulties in measuring movements of the hand. Recent developments in methods of motion capture and analysis mean it is now possible to explore the intricate movements of the hand and fingers. These methods allow us insights into the neurophysiological mechanisms underpinning complex hand dexterity and motor learning. They also allow investigation into the key factors that contribute to injury, recovery and functional compensation.The application of such analytical techniques within musical performance provides a multidisciplinary framework for purposeful investigation into the process of learning and skill acquisition in instrumental performance. These highly skilled manual and cognitive tasks present the ultimate achievement in complex hand dexterity. This paper will review methods of assessing instrumental performance in music, focusing specifically on biomechanical measurement and the associated technical challenges faced when measuring highly dexterous activities.

Investigation of human-robot interface performance in household environments

Science.gov (United States)

Cremer, Sven; Mirza, Fahad; Tuladhar, Yathartha; Alonzo, Rommel; Hingeley, Anthony; Popa, Dan O.

2016-05-01

Today, assistive robots are being introduced into human environments at an increasing rate. Human environments are highly cluttered and dynamic, making it difficult to foresee all necessary capabilities and pre-program all desirable future skills of the robot. One approach to increase robot performance is semi-autonomous operation, allowing users to intervene and guide the robot through difficult tasks. To this end, robots need intuitive Human-Machine Interfaces (HMIs) that support fine motion control without overwhelming the operator. In this study we evaluate the performance of several interfaces that balance autonomy and teleoperation of a mobile manipulator for accomplishing several household tasks. Our proposed HMI framework includes teleoperation devices such as a tablet, as well as physical interfaces in the form of piezoresistive pressure sensor arrays. Mobile manipulation experiments were performed with a sensorized KUKA youBot, an omnidirectional platform with a 5 degrees of freedom (DOF) arm. The pick and place tasks involved navigation and manipulation of objects in household environments. Performance metrics included time for task completion and position accuracy.

Optimation and Determination of Fe-Oxinate Complex by Using High Performance Liquid Chromatography

Science.gov (United States)

Oktavia, B.; Nasra, E.; Sary, R. C.

2018-04-01

The need for iron will improve the industrial processes that require iron as its raw material. Control of industrial iron waste is very important to do. One method of iron analysis is to conduct indirect analysis of iron (III) ions by complexing with 8-Hydroxyquinoline or oxine. In this research, qualitative and quantitative tests of iron (III) ions in the form of complex with oxine. The analysis was performed using HPLC at a wavelength of 470 nm with an ODS C18 column. Three methods of analysis were performed: 1) Fe-oxinate complexes were prepared in an ethanol solvent so no need for separation anymore, (2) Fe-oxinate complexes were made in chloroform so that a solvent extraction was required before the complex was injected into the column while the third complex was formed in the column, wherein the eluent contains the oxide and the metal ions are then injected. The resulting chromatogram shows that the 3rd way provides a better chromatogram for iron analysis.

Where to from here? Future applications of mental models of complex performance

International Nuclear Information System (INIS)

Hahn, H.A.; Nelson, W.R.; Blackman, H.S.

1988-01-01

The purpose of this paper is to raise issues for discussion regarding the applications of mental models in the study of complex performance. Applications for training, expert systems and decision aids, job selection, workstation design, and other complex environments are considered. 1 ref

Task complexity, student perceptions of vocabulary learning in EFL, and task performance.

Science.gov (United States)

Wu, Xiaoli; Lowyck, Joost; Sercu, Lies; Elen, Jan

2013-03-01

The study deepened our understanding of how students' self-efficacy beliefs contribute to the context of teaching English as a foreign language in the framework of cognitive mediational paradigm at a fine-tuned task-specific level. The aim was to examine the relationship among task complexity, self-efficacy beliefs, domain-related prior knowledge, learning strategy use, and task performance as they were applied to English vocabulary learning from reading tasks. Participants were 120 second-year university students (mean age 21) from a Chinese university. This experiment had two conditions (simple/complex). A vocabulary level test was first conducted to measure participants' prior knowledge of English vocabulary. Participants were then randomly assigned to one of the learning tasks. Participants were administered task booklets together with the self-efficacy scales, measures of learning strategy use, and post-tests. Data obtained were submitted to multivariate analysis of variance (MANOVA) and path analysis. Results from the MANOVA model showed a significant effect of vocabulary level on self-efficacy beliefs, learning strategy use, and task performance. Task complexity showed no significant effect; however, an interaction effect between vocabulary level and task complexity emerged. Results from the path analysis showed self-efficacy beliefs had an indirect effect on performance. Our results highlighted the mediating role of self-efficacy beliefs and learning strategy use. Our findings indicate that students' prior knowledge plays a crucial role on both self-efficacy beliefs and task performance, and the predictive power of self-efficacy on task performance may lie in its association with learning strategy use. © 2011 The British Psychological Society.

The effects of physical threat on team processes during complex task performance

NARCIS (Netherlands)

Kamphuis, W.; Gaillard, A.W.K.; Vogelaar, A.L.W.

2011-01-01

Teams have become the norm for operating in dangerous and complex situations. To investigate how physical threat affects team performance, 27 threeperson teams engaged in a complex planning and problem-solving task, either under physical threat or under normal conditions. Threat consisted of the

A low complexity visualization tool that helps to perform complex systems analysis

International Nuclear Information System (INIS)

Beiro, M G; Alvarez-Hamelin, J I; Busch, J R

2008-01-01

In this paper, we present an extension of large network visualization (LaNet-vi), a tool to visualize large scale networks using the k-core decomposition. One of the new features is how vertices compute their angular position. While in the later version it is done using shell clusters, in this version we use the angular coordinate of vertices in higher k-shells, and arrange the highest shell according to a cliques decomposition. The time complexity goes from O(n√n) to O(n) upon bounds on a heavy-tailed degree distribution. The tool also performs a k-core-connectivity analysis, highlighting vertices that are not k-connected; e.g. this property is useful to measure robustness or quality of service (QoS) capabilities in communication networks. Finally, the actual version of LaNet-vi can draw labels and all the edges using transparencies, yielding an accurate visualization. Based on the obtained figure, it is possible to distinguish different sources and types of complex networks at a glance, in a sort of 'network iris-print'.

A low complexity visualization tool that helps to perform complex systems analysis

Science.gov (United States)

Beiró, M. G.; Alvarez-Hamelin, J. I.; Busch, J. R.

2008-12-01

In this paper, we present an extension of large network visualization (LaNet-vi), a tool to visualize large scale networks using the k-core decomposition. One of the new features is how vertices compute their angular position. While in the later version it is done using shell clusters, in this version we use the angular coordinate of vertices in higher k-shells, and arrange the highest shell according to a cliques decomposition. The time complexity goes from O(n\\sqrt n) to O(n) upon bounds on a heavy-tailed degree distribution. The tool also performs a k-core-connectivity analysis, highlighting vertices that are not k-connected; e.g. this property is useful to measure robustness or quality of service (QoS) capabilities in communication networks. Finally, the actual version of LaNet-vi can draw labels and all the edges using transparencies, yielding an accurate visualization. Based on the obtained figure, it is possible to distinguish different sources and types of complex networks at a glance, in a sort of 'network iris-print'.

The Effect of Performance-Contingent Incentives when Task Complexity is Manipulated through Instruction

Directory of Open Access Journals (Sweden)

Monte Wynder

2010-12-01

Full Text Available When, and how, performance-contingent incentives improve performance is an important question fororganisations. Empirical results have been mixed – performance-contingent incentives sometimes increaseperformance, sometimes decrease performance, and sometimes have no effect. Theorists have called forfurther research to identify the effect of various moderating variables, including knowledge and taskcomplexity. This study responds by considering the role of instruction in providing the necessary knowledgeto reduce task complexity. The results suggest that a performance-contingent penalty can be a particularlyeffective means of directing effort for a simple task. For a complex task, performance can be improvedthrough instruction. The type of instruction is important – with rule-based instruction effectively directingeffort – however principle-based instruction is necessary to facilitate problem investigation and problemsolving.

HIGH PERFORMANCE PIAA CORONAGRAPHY WITH COMPLEX AMPLITUDE FOCAL PLANE MASKS

International Nuclear Information System (INIS)

Guyon, Olivier; Martinache, Frantz; Belikov, Ruslan; Soummer, Remi

2010-01-01

We describe a coronagraph approach where the performance of a Phase-Induced Amplitude Apodization (PIAA) coronagraph is improved by using a partially transmissive phase-shifting focal plane mask and a Lyot stop. This approach combines the low inner working angle offered by phase mask coronagraphy, the full throughput and uncompromized angular resolution of the PIAA approach, and the design flexibility of Apodized Pupil Lyot Coronagraph. A PIAA complex mask coronagraph (PIAACMC) is fully described by the focal plane mask size, or, equivalently, its complex transmission which ranges from 0 (opaque) to -1 (phase shifting). For all values of the transmission, the PIAACMC theoretically offers full on-axis extinction and 100% throughput at large angular separations. With a pure phase focal plane mask (complex transmission = -1), the PIAACMC offers 50% throughput at 0.64 λ/D while providing total extinction of an on-axis point source. This performance is very close to the 'fundamental performance limit' of coronagraphy derived from first principles. For very high contrast level, imaging performance with PIAACMC is in practice limited by the angular size of the on-axis target (usually a star). We show that this fundamental limitation must be taken into account when choosing the optimal value of the focal plane mask size in the PIAACMC design. We show that the PIAACMC enables visible imaging of Jupiter-like planets at ∼1.2 λ/D from the host star, and can therefore offer almost three times more targets than a PIAA coronagraph optimized for this type of observation. We find that for visible imaging of Earth-like planets, the PIAACMC gain over a PIAA is probably much smaller, as coronagraphic performance is then strongly constrained by stellar angular size. For observations at 'low' contrast (below ∼ 10 8 ), the PIAACMC offers significant performance enhancement over PIAA. This is especially relevant for ground-based high contrast imaging systems in the near-IR, where

Variations in task constraints shape emergent performance outcomes and complexity levels in balancing.

Science.gov (United States)

Caballero Sánchez, Carla; Barbado Murillo, David; Davids, Keith; Moreno Hernández, Francisco J

2016-06-01

This study investigated the extent to which specific interacting constraints of performance might increase or decrease the emergent complexity in a movement system, and whether this could affect the relationship between observed movement variability and the central nervous system's capacity to adapt to perturbations during balancing. Fifty-two healthy volunteers performed eight trials where different performance constraints were manipulated: task difficulty (three levels) and visual biofeedback conditions (with and without the center of pressure (COP) displacement and a target displayed). Balance performance was assessed using COP-based measures: mean velocity magnitude (MVM) and bivariate variable error (BVE). To assess the complexity of COP, fuzzy entropy (FE) and detrended fluctuation analysis (DFA) were computed. ANOVAs showed that MVM and BVE increased when task difficulty increased. During biofeedback conditions, individuals showed higher MVM but lower BVE at the easiest level of task difficulty. Overall, higher FE and lower DFA values were observed when biofeedback was available. On the other hand, FE reduced and DFA increased as difficulty level increased, in the presence of biofeedback. However, when biofeedback was not available, the opposite trend in FE and DFA values was observed. Regardless of changes to task constraints and the variable investigated, balance performance was positively related to complexity in every condition. Data revealed how specificity of task constraints can result in an increase or decrease in complexity emerging in a neurobiological system during balance performance.

Does model performance improve with complexity? A case study with three hydrological models

Science.gov (United States)

Orth, Rene; Staudinger, Maria; Seneviratne, Sonia I.; Seibert, Jan; Zappa, Massimiliano

2015-04-01

In recent decades considerable progress has been made in climate model development. Following the massive increase in computational power, models became more sophisticated. At the same time also simple conceptual models have advanced. In this study we validate and compare three hydrological models of different complexity to investigate whether their performance varies accordingly. For this purpose we use runoff and also soil moisture measurements, which allow a truly independent validation, from several sites across Switzerland. The models are calibrated in similar ways with the same runoff data. Our results show that the more complex models HBV and PREVAH outperform the simple water balance model (SWBM) in case of runoff but not for soil moisture. Furthermore the most sophisticated PREVAH model shows an added value compared to the HBV model only in case of soil moisture. Focusing on extreme events we find generally improved performance of the SWBM during drought conditions and degraded agreement with observations during wet extremes. For the more complex models we find the opposite behavior, probably because they were primarily developed for prediction of runoff extremes. As expected given their complexity, HBV and PREVAH have more problems with over-fitting. All models show a tendency towards better performance in lower altitudes as opposed to (pre-) alpine sites. The results vary considerably across the investigated sites. In contrast, the different metrics we consider to estimate the agreement between models and observations lead to similar conclusions, indicating that the performance of the considered models is similar at different time scales as well as for anomalies and long-term means. We conclude that added complexity does not necessarily lead to improved performance of hydrological models, and that performance can vary greatly depending on the considered hydrological variable (e.g. runoff vs. soil moisture) or hydrological conditions (floods vs. droughts).

Can motto-goals outperform learning and performance goals? Influence of goal setting on performance and affect in a complex problem solving task

Directory of Open Access Journals (Sweden)

Miriam S. Rohe

2016-09-01

Full Text Available In this paper, we bring together research on complex problem solving with that on motivational psychology about goal setting. Complex problems require motivational effort because of their inherent difficulties. Goal Setting Theory has shown with simple tasks that high, specific performance goals lead to better performance outcome than do-your-best goals. However, in complex tasks, learning goals have proven more effective than performance goals. Based on the Zurich Resource Model (Storch & Krause, 2014, so-called motto-goals (e.g., "I breathe happiness" should activate a person’s resources through positive affect. It was found that motto-goals are effective with unpleasant duties. Therefore, we tested the hypothesis that motto-goals outperform learning and performance goals in the case of complex problems. A total of N = 123 subjects participated in the experiment. In dependence of their goal condition, subjects developed a personal motto, learning, or performance goal. This goal was adapted for the computer-simulated complex scenario Tailorshop, where subjects worked as managers in a small fictional company. Other than expected, there was no main effect of goal condition for the management performance. As hypothesized, motto goals led to higher positive and lower negative affect than the other two goal types. Even though positive affect decreased and negative affect increased in all three groups during Tailorshop completion, participants with motto goals reported the lowest rates of negative affect over time. Exploratory analyses investigated the role of affect in complex problem solving via mediational analyses and the influence of goal type on perceived goal attainment.

A Novel Method for Assessing Task Complexity in Outpatient Clinical-Performance Measures.

Science.gov (United States)

Hysong, Sylvia J; Amspoker, Amber B; Petersen, Laura A

2016-04-01

Clinical-performance measurement has helped improve the quality of health-care; yet success in attaining high levels of quality across multiple domains simultaneously still varies considerably. Although many sources of variability in care quality have been studied, the difficulty required to complete the clinical work itself has received little attention. We present a task-based methodology for evaluating the difficulty of clinical-performance measures (CPMs) by assessing the complexity of their component requisite tasks. Using Functional Job Analysis (FJA), subject-matter experts (SMEs) generated task lists for 17 CPMs; task lists were rated on ten dimensions of complexity, and then aggregated into difficulty composites. Eleven outpatient work SMEs; 133 VA Medical Centers nationwide. Clinical Performance: 17 outpatient CPMs (2000-2008) at 133 VA Medical Centers nationwide. Measure Difficulty: for each CPM, the number of component requisite tasks and the average rating across ten FJA complexity scales for the set of tasks comprising the measure. Measures varied considerably in the number of component tasks (M = 10.56, SD = 6.25, min = 5, max = 25). Measures of chronic care following acute myocardial infarction exhibited significantly higher measure difficulty ratings compared to diabetes or screening measures, but not to immunization measures ([Formula: see text] = 0.45, -0.04, -0.05, and -0.06 respectively; F (3, 186) = 3.57, p = 0.015). Measure difficulty ratings were not significantly correlated with the number of component tasks (r = -0.30, p = 0.23). Evaluating the difficulty of achieving recommended CPM performance levels requires more than simply counting the tasks involved; using FJA to assess the complexity of CPMs' component tasks presents an alternate means of assessing the difficulty of primary-care CPMs and accounting for performance variation among measures and performers. This in turn could be used in designing

The disruptive effects of pain on complex cognitive performance and executive control.

Directory of Open Access Journals (Sweden)

Edmund Keogh

Full Text Available Pain interferes and disrupts attention. What is less clear is how pain affects performance on complex tasks, and the strategies used to ensure optimal outcomes. The aim of the current study was to examine the effect of pain on higher-order executive control processes involved in managing complex tasks. Sixty-two adult volunteers (40 female completed two computer-based tasks: a breakfast making task and a word generation puzzle. Both were complex, involving executive control functions, including goal-directed planning and switching. Half of those recruited performed the tasks under conditions of thermal heat pain, and half with no accompanying pain. Whilst pain did not affect central performance on either task, it did have indirect effects. For the breakfast task, pain resulted in a decreased ability to multitask, with performance decrements found on the secondary task. However, no effects of pain were found on the processes thought to underpin this task. For the word generation puzzle, pain did not affect task performance, but did alter subjective accounts of the processes used to complete the task; pain affected the perceived allocation of time to the task, as well as switching perceptions. Sex differences were also found. When studying higher-order cognitive processes, pain-related interference effects are varied, and may result in subtle or indirect changes in cognition.

The disruptive effects of pain on complex cognitive performance and executive control.

Science.gov (United States)

Keogh, Edmund; Moore, David J; Duggan, Geoffrey B; Payne, Stephen J; Eccleston, Christopher

2013-01-01

Pain interferes and disrupts attention. What is less clear is how pain affects performance on complex tasks, and the strategies used to ensure optimal outcomes. The aim of the current study was to examine the effect of pain on higher-order executive control processes involved in managing complex tasks. Sixty-two adult volunteers (40 female) completed two computer-based tasks: a breakfast making task and a word generation puzzle. Both were complex, involving executive control functions, including goal-directed planning and switching. Half of those recruited performed the tasks under conditions of thermal heat pain, and half with no accompanying pain. Whilst pain did not affect central performance on either task, it did have indirect effects. For the breakfast task, pain resulted in a decreased ability to multitask, with performance decrements found on the secondary task. However, no effects of pain were found on the processes thought to underpin this task. For the word generation puzzle, pain did not affect task performance, but did alter subjective accounts of the processes used to complete the task; pain affected the perceived allocation of time to the task, as well as switching perceptions. Sex differences were also found. When studying higher-order cognitive processes, pain-related interference effects are varied, and may result in subtle or indirect changes in cognition.

Benchmarking in pathology: development of a benchmarking complexity unit and associated key performance indicators.

Science.gov (United States)

Neil, Amanda; Pfeffer, Sally; Burnett, Leslie

2013-01-01

This paper details the development of a new type of pathology laboratory productivity unit, the benchmarking complexity unit (BCU). The BCU provides a comparative index of laboratory efficiency, regardless of test mix. It also enables estimation of a measure of how much complex pathology a laboratory performs, and the identification of peer organisations for the purposes of comparison and benchmarking. The BCU is based on the theory that wage rates reflect productivity at the margin. A weighting factor for the ratio of medical to technical staff time was dynamically calculated based on actual participant site data. Given this weighting, a complexity value for each test, at each site, was calculated. The median complexity value (number of BCUs) for that test across all participating sites was taken as its complexity value for the Benchmarking in Pathology Program. The BCU allowed implementation of an unbiased comparison unit and test listing that was found to be a robust indicator of the relative complexity for each test. Employing the BCU data, a number of Key Performance Indicators (KPIs) were developed, including three that address comparative organisational complexity, analytical depth and performance efficiency, respectively. Peer groups were also established using the BCU combined with simple organisational and environmental metrics. The BCU has enabled productivity statistics to be compared between organisations. The BCU corrects for differences in test mix and workload complexity of different organisations and also allows for objective stratification into peer groups.

Executive Functioning and School Performance Among Pediatric Survivors of Complex Congenital Heart Disease

Science.gov (United States)

Gerstle, Melissa; Beebe, Dean W.; Drotar, Dennis; Cassedy, Amy; Marino, Bradley S.

2016-01-01

Objective To investigate the presence and severity of real-world impairments in executive functioning– responsible for children’s regulatory skills (metacognition, behavioral regulation) – and its potential impact on school performance among pediatric survivors of complex congenital heart disease (CHD). Study design Survivors of complex CHD aged 8–16 years (n=143)and their parents/guardians from a regional CHD survivor registry participated (81% participation rate). Parents completed proxy measures of executive functioning, school competency, and school-related quality of life (QOL). Patients also completed a measure of school QOL and underwent IQ testing. Patients were categorized into two groups based on heart lesion complexity: two-ventricle or single-ventricle. Results Survivors of complex CHD performed significantly worse than norms for executive functioning, IQ, school competency, and school QOL. Metacognition was more severely affected than behavioral regulation, and metacognitive deficits were more often present in older children. Even after taking into account demographic factors, disease severity, and IQ, metacognition uniquely and strongly predicted poorer school performance. In exploratory analyses, patients with single-ventricle lesions were rated as having lower school competency and school QOL, and patients with two-ventricle lesions were rated as having poorer behavioral regulation. Conclusions Survivors of complex CHD experience greater executive functioning difficulties than healthy peers, with metacognition particularly impacted and particularly relevant for day-to-day school performance. Especially in older children, clinicians should watch for metacognitive deficits, such as problems with organization, planning, self-monitoring, and follow-through on tasks. PMID:26875011

Measuring cognitive load: performance, mental effort and simulation task complexity.

Science.gov (United States)

Haji, Faizal A; Rojas, David; Childs, Ruth; de Ribaupierre, Sandrine; Dubrowski, Adam

2015-08-01

Interest in applying cognitive load theory in health care simulation is growing. This line of inquiry requires measures that are sensitive to changes in cognitive load arising from different instructional designs. Recently, mental effort ratings and secondary task performance have shown promise as measures of cognitive load in health care simulation. We investigate the sensitivity of these measures to predicted differences in intrinsic load arising from variations in task complexity and learner expertise during simulation-based surgical skills training. We randomly assigned 28 novice medical students to simulation training on a simple or complex surgical knot-tying task. Participants completed 13 practice trials, interspersed with computer-based video instruction. On trials 1, 5, 9 and 13, knot-tying performance was assessed using time and movement efficiency measures, and cognitive load was assessed using subjective rating of mental effort (SRME) and simple reaction time (SRT) on a vibrotactile stimulus-monitoring secondary task. Significant improvements in knot-tying performance (F(1.04,24.95)  = 41.1, p cognitive load (F(2.3,58.5)  = 57.7, p load among novices engaged in simulation-based learning. These measures can be used to track cognitive load during skills training. Mental effort ratings are also sensitive to small differences in intrinsic load arising from variations in the physical complexity of a simulation task. The complementary nature of these subjective and objective measures suggests their combined use is advantageous in simulation instructional design research. © 2015 John Wiley & Sons Ltd.

Effects of orientation on Rey complex figure performance.

Science.gov (United States)

Ferraro, F Richard; Grossman, Jennifer; Bren, Amy; Hoverson, Allysa

2002-10-01

An experiment was performed that examined the impact of stimulus orientation on performance on the Rey complex figure. A total of 48 undergraduates (24 men, 24 women) were randomly assigned to one of four Rey figure orientation groups (0 degrees, 90 degrees, 180 degrees, and 270 degrees ). Participants followed standard procedures for the Rey figure, initially copying it in whatever orientation group they were assigned to. Next, all participants performed a 15-20 min lexical decision experiment, used as a filler task. Finally, and unbeknownest to them, participants were asked to recall as much of the figure as they could. As expected, results revealed a main effect of Task (F = 83.92, p orientation was not significant, nor did orientation interact with task (Fs .57). The results are important from an applied setting, especially if testing conditions are less than optimal and a fixed stimulus position is not possible (e.g., testing at the bedside).

42 CFR 493.1415 - Condition: Laboratories performing moderate complexity testing; clinical consultant.

Science.gov (United States)

2010-10-01

... § 493.1415 Condition: Laboratories performing moderate complexity testing; clinical consultant. The laboratory must have a clinical consultant who meets the qualification requirements of § 493.1417 of this... 42 Public Health 5 2010-10-01 2010-10-01 false Condition: Laboratories performing moderate...

Atmospheric stability and topography effects on wind turbine performance and wake properties in complex terrain

DEFF Research Database (Denmark)

Han, Xingxing; Liu, Deyou; Xu, Chang

2018-01-01

This paper evaluates the influence of atmospheric stability and topography on wind turbine performance and wake properties in complex terrain. To assess atmospheric stability effects on wind turbine performance, an equivalent wind speed calculated with the power output and the manufacture power...... and topography have significant influences on wind turbine performance and wake properties. Considering effects of atmospheric stability and topography will benefit the wind resource assessment in complex terrain....

The Influence of Time Pressure and Case Complexity on Physicians׳ Diagnostic Performance

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Dalal A. ALQahtani

2016-12-01

Conclusions: Time pressure did not impact the diagnostic performance, whereas the complexity of the clinical case negatively influenced the diagnostic accuracy. Further studies with the enhanced experimental manipulation of time pressure are needed to reveal the effect of time pressure, if any, on a physician׳s diagnostic performance.

Performance and Complexity Evaluation of Iterative Receiver for Coded MIMO-OFDM Systems

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Rida El Chall

2016-01-01

Full Text Available Multiple-input multiple-output (MIMO technology in combination with channel coding technique is a promising solution for reliable high data rate transmission in future wireless communication systems. However, these technologies pose significant challenges for the design of an iterative receiver. In this paper, an efficient receiver combining soft-input soft-output (SISO detection based on low-complexity K-Best (LC-K-Best decoder with various forward error correction codes, namely, LTE turbo decoder and LDPC decoder, is investigated. We first investigate the convergence behaviors of the iterative MIMO receivers to determine the required inner and outer iterations. Consequently, the performance of LC-K-Best based receiver is evaluated in various LTE channel environments and compared with other MIMO detection schemes. Moreover, the computational complexity of the iterative receiver with different channel coding techniques is evaluated and compared with different modulation orders and coding rates. Simulation results show that LC-K-Best based receiver achieves satisfactory performance-complexity trade-offs.

Performance Analysis with Network-Enhanced Complexities: On Fading Measurements, Event-Triggered Mechanisms, and Cyber Attacks

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Derui Ding

2014-01-01

Full Text Available Nowadays, the real-world systems are usually subject to various complexities such as parameter uncertainties, time-delays, and nonlinear disturbances. For networked systems, especially large-scale systems such as multiagent systems and systems over sensor networks, the complexities are inevitably enhanced in terms of their degrees or intensities because of the usage of the communication networks. Therefore, it would be interesting to (1 examine how this kind of network-enhanced complexities affects the control or filtering performance; and (2 develop some suitable approaches for controller/filter design problems. In this paper, we aim to survey some recent advances on the performance analysis and synthesis with three sorts of fashionable network-enhanced complexities, namely, fading measurements, event-triggered mechanisms, and attack behaviors of adversaries. First, these three kinds of complexities are introduced in detail according to their engineering backgrounds, dynamical characteristic, and modelling techniques. Then, the developments of the performance analysis and synthesis issues for various networked systems are systematically reviewed. Furthermore, some challenges are illustrated by using a thorough literature review and some possible future research directions are highlighted.

Software Performs Complex Design Analysis

Science.gov (United States)

2008-01-01

Designers use computational fluid dynamics (CFD) to gain greater understanding of the fluid flow phenomena involved in components being designed. They also use finite element analysis (FEA) as a tool to help gain greater understanding of the structural response of components to loads, stresses and strains, and the prediction of failure modes. Automated CFD and FEA engineering design has centered on shape optimization, which has been hindered by two major problems: 1) inadequate shape parameterization algorithms, and 2) inadequate algorithms for CFD and FEA grid modification. Working with software engineers at Stennis Space Center, a NASA commercial partner, Optimal Solutions Software LLC, was able to utilize its revolutionary, one-of-a-kind arbitrary shape deformation (ASD) capability-a major advancement in solving these two aforementioned problems-to optimize the shapes of complex pipe components that transport highly sensitive fluids. The ASD technology solves the problem of inadequate shape parameterization algorithms by allowing the CFD designers to freely create their own shape parameters, therefore eliminating the restriction of only being able to use the computer-aided design (CAD) parameters. The problem of inadequate algorithms for CFD grid modification is solved by the fact that the new software performs a smooth volumetric deformation. This eliminates the extremely costly process of having to remesh the grid for every shape change desired. The program can perform a design change in a markedly reduced amount of time, a process that would traditionally involve the designer returning to the CAD model to reshape and then remesh the shapes, something that has been known to take hours, days-even weeks or months-depending upon the size of the model.

Performance of community health workers:situating their intermediary position within complex adaptive health systems

OpenAIRE

Kok, Maryse. C; Broerse, Jacqueline E.W; Theobald, Sally; Ormel, Hermen; Dieleman, Marjolein; Taegtmeyer, Miriam

2017-01-01

Health systems are social institutions, in which health worker performance is shaped by transactional processes between different actors. This analytical assessment unravels the complex web of factors that influence the performance of community health workers (CHWs) in low- and middle-income countries. It examines their unique intermediary position between the communities they serve and actors in the health sector, and the complexity of the health systems in which they operate. The assessment...

Measuring working memory in aphasia: Comparing performance on complex span and N-back tasks

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Maria Ivanova

2014-04-01

No significant correlations were observed between performance on complex span task and N-back tasks.Furthermore, performance on the modified listening span was related to performance on the comprehension subtest of the QASA, while no relationship was found for 2-back and 0-back tasks.Our results mirror studies in healthy controls that demonstrated no relationship between performance on the two tasks(Jaeggi et al., 2010; Kane et al., 2007. Thus although N-back tasks seem similar to traditional complex span measures and may also index abilities related to cognitive processing, the evidence to date does not warrant their direct association with the construct of WM. Implications for future investigation of cognitive deficits in aphasia will be discussed.

Polerovirus protein P0 prevents the assembly of small RNA-containing RISC complexes and leads to degradation of ARGONAUTE1.

Science.gov (United States)

Csorba, Tibor; Lózsa, Rita; Hutvágner, György; Burgyán, József

2010-05-01

RNA silencing plays an important role in plants in defence against viruses. To overcome this defence, plant viruses encode suppressors of RNA silencing. The most common mode of silencing suppression is sequestration of double-stranded RNAs involved in the antiviral silencing pathways. Viral suppressors can also overcome silencing responses through protein-protein interaction. The poleroviral P0 silencing suppressor protein targets ARGONAUTE (AGO) proteins for degradation. AGO proteins are the core component of the RNA-induced silencing complex (RISC). We found that P0 does not interfere with the slicer activity of pre-programmed siRNA/miRNA containing AGO1, but prevents de novo formation of siRNA/miRNA containing AGO1. We show that the AGO1 protein is part of a high-molecular-weight complex, suggesting the existence of a multi-protein RISC in plants. We propose that P0 prevents RISC assembly by interacting with one of its protein components, thus inhibiting formation of siRNA/miRNA-RISC, and ultimately leading to AGO1 degradation. Our findings also suggest that siRNAs enhance the stability of co-expressed AGO1 in both the presence and absence of P0.

The effect of two complexity factors on the performance of emergency tasks-An experimental verification

International Nuclear Information System (INIS)

Park, Jinkyun; Jung, Wondea; Jung, Kwangtae

2008-01-01

It is well known that the use of procedures is very important in securing the safety of process systems, since good procedures effectively guide human operators by providing 'what should be done' and 'how to do it', especially under stressful conditions. At the same time, it has been emphasized that the use of complicated procedures could drastically impair operators' performance. This means that a systematic approach that can properly evaluate the complexity of procedures is indispensable for minimizing the side effects of complicated procedures. For this reason, Park et al. have developed a task complexity measure called TACOM that can be used to quantify the complexity of tasks stipulated in emergency operating procedures (EOPs) of nuclear power plants (NPPs). The TACOM measure consists of five sub-measures that can cover five important factors making the performance of emergency tasks complicated. However, a verification activity for two kinds of complexity factors-the level of abstraction hierarchy (AH) and engineering decision (ED)-seems to be insufficient. In this study, therefore, an experiment is conducted by using a low-fidelity simulator in order to clarify the appropriateness of these complexity factors. As a result, it seems that subjects' performance data are affected by the level of AH as well as ED. Therefore it is anticipate that both the level of AH and ED will play an important role in evaluating the complexity of EOPs

Obesity-specific neural cost of maintaining gait performance under complex conditions in community-dwelling older adults.

Science.gov (United States)

Osofundiya, Olufunmilola; Benden, Mark E; Dowdy, Diane; Mehta, Ranjana K

2016-06-01

Recent evidence of obesity-related changes in the prefrontal cortex during cognitive and seated motor activities has surfaced; however, the impact of obesity on neural activity during ambulation remains unclear. The purpose of this study was to determine obesity-specific neural cost of simple and complex ambulation in older adults. Twenty non-obese and obese individuals, 65years and older, performed three tasks varying in the types of complexity of ambulation (simple walking, walking+cognitive dual-task, and precision walking). Maximum oxygenated hemoglobin, a measure of neural activity, was measured bilaterally using a portable functional near infrared spectroscopy system, and gait speed and performance on the complex tasks were also obtained. Complex ambulatory tasks were associated with ~2-3.5 times greater cerebral oxygenation levels and ~30-40% slower gait speeds when compared to the simple walking task. Additionally, obesity was associated with three times greater oxygenation levels, particularly during the precision gait task, despite obese adults demonstrating similar gait speeds and performances on the complex gait tasks as non-obese adults. Compared to existing studies that focus solely on biomechanical outcomes, the present study is one of the first to examine obesity-related differences in neural activity during ambulation in older adults. In order to maintain gait performance, obesity was associated with higher neural costs, and this was augmented during ambulatory tasks requiring greater precision control. These preliminary findings have clinical implications in identifying individuals who are at greater risk of mobility limitations, particularly when performing complex ambulatory tasks. Copyright © 2016 Elsevier Ltd. All rights reserved.

High-Speed, High-Performance DQPSK Optical Links with Reduced Complexity VDFE Equalizers

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Maki Nanou

2017-02-01

Full Text Available Optical transmission technologies optimized for optical network segments sensitive to power consumption and cost, comprise modulation formats with direct detection technologies. Specifically, non-return to zero differential quaternary phase shift keying (NRZ-DQPSK in deployed fiber plants, combined with high-performance, low-complexity electronic equalizers to compensate residual impairments at the receiver end, can be proved as a viable solution for high-performance, high-capacity optical links. Joint processing of the constructive and the destructive signals at the single-ended DQPSK receiver provides improved performance compared to the balanced configuration, however, at the expense of higher hardware requirements, a fact that may not be neglected especially in the case of high-speed optical links. To overcome this bottleneck, the use of partially joint constructive/destructive DQPSK equalization is investigated in this paper. Symbol-by-symbol equalization is performed by means of Volterra decision feedback-type equalizers, driven by a reduced subset of signals selected from the constructive and the destructive ports of the optical detectors. The proposed approach offers a low-complexity alternative for electronic equalization, without sacrificing much of the performance compared to the fully-deployed counterpart. The efficiency of the proposed equalizers is demonstrated by means of computer simulation in a typical optical transmission scenario.

Wind turbine power performance verification in complex terrain and wind farms

DEFF Research Database (Denmark)

Friis Pedersen, Troels; Gjerding, S.; Enevoldsen, P.

2002-01-01

is a power performance verification procedure for individual wind turbines. The third is a power performance measurement procedure of whole wind farms, and the fourth is a power performance measurement procedurefor non-grid (small) wind turbines. This report presents work that was made to support the basis......The IEC/EN 61400-12 Ed 1 standard for wind turbine power performance testing is being revised. The standard will be divided into four documents. The first one of these is more or less a revision of the existing document on power performance measurementson individual wind turbines. The second one...... then been investigated in more detail. The work has given rise to a range of conclusionsand recommendations regarding: guaranties on power curves in complex terrain; investors and bankers experience with verification of power curves; power performance in relation to regional correction curves for Denmark...

The Effects of Differential Goal Weights on the Performance of a Complex Financial Task.

Science.gov (United States)

Edmister, Robert O.; Locke, Edwin A.

1987-01-01

Determined whether people could obtain outcomes on a complex task that would be in line with differential goal weights corresponding to different aspects of the task. Bank lending officers were run through lender-simulation exercises. Five performance goals were weighted. Demonstrated effectiveness of goal setting with complex tasks, using group…

Improving performance of DS-CDMA systems using chaotic complex Bernoulli spreading codes

Science.gov (United States)

Farzan Sabahi, Mohammad; Dehghanfard, Ali

2014-12-01

The most important goal of spreading spectrum communication system is to protect communication signals against interference and exploitation of information by unintended listeners. In fact, low probability of detection and low probability of intercept are two important parameters to increase the performance of the system. In Direct Sequence Code Division Multiple Access (DS-CDMA) systems, these properties are achieved by multiplying the data information in spreading sequences. Chaotic sequences, with their particular properties, have numerous applications in constructing spreading codes. Using one-dimensional Bernoulli chaotic sequence as spreading code is proposed in literature previously. The main feature of this sequence is its negative auto-correlation at lag of 1, which with proper design, leads to increase in efficiency of the communication system based on these codes. On the other hand, employing the complex chaotic sequences as spreading sequence also has been discussed in several papers. In this paper, use of two-dimensional Bernoulli chaotic sequences is proposed as spreading codes. The performance of a multi-user synchronous and asynchronous DS-CDMA system will be evaluated by applying these sequences under Additive White Gaussian Noise (AWGN) and fading channel. Simulation results indicate improvement of the performance in comparison with conventional spreading codes like Gold codes as well as similar complex chaotic spreading sequences. Similar to one-dimensional Bernoulli chaotic sequences, the proposed sequences also have negative auto-correlation. Besides, construction of complex sequences with lower average cross-correlation is possible with the proposed method.

Cognitive function predicts listening effort performance during complex tasks in normally aging adults

Directory of Open Access Journals (Sweden)

Jennine Harvey

2017-01-01

Full Text Available Purpose: This study examines whether cognitive function, as measured by the subtests of the Woodcock–Johnson III (WCJ-III assessment, predicts listening-effort performance during dual tasks across the adults of varying ages. Materials and Methods: Participants were divided into two groups. Group 1 consisted of 14 listeners (number of females = 11 who were 41–61 years old [mean = 53.18; standard deviation (SD = 5.97]. Group 2 consisted of 15 listeners (number of females = 9 who were 63–81 years old (mean = 72.07; SD = 5.11. Participants were administered the WCJ-III Memory for Words, Auditory Working Memory, Visual Matching, and Decision Speed subtests. All participants were tested in each of the following three dual-task experimental conditions, which were varying in complexity: (1 auditory word recognition + visual processing, (2 auditory working memory (word + visual processing, and (3 auditory working memory (sentence + visual processing in noise. Results: A repeated measures analysis of variance revealed that task complexity significantly affected the performance measures of auditory accuracy, visual accuracy, and processing speed. Linear regression revealed that the cognitive subtests of the WCJ-III test significantly predicted performance across dependent variable measures. Conclusion: Listening effort is significantly affected by task complexity, regardless of age. Performance on the WCJ-III test may predict listening effort in adults and may assist speech-language pathologist (SLPs to understand challenges faced by participants when subjected to noise.

Complex Analysis of Financial State and Performance of Construction Enterprises

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Algirdas Krivka

2015-12-01

Full Text Available The paper analyses the financial state and performance of large constructions enterprises by applying financial indicators. As there is no one single decisive financial indicator enabling to objectively assess enterprise performance, the multi-criteria decision making (MCDM methods are applied with four groups of financial ratios (profitability, liquidity, solvency and asset turnover acting as evaluation criteria, while the alternatives assessed are two enterprises compared throughout the reference period of three years, also with the average indicator values of the whole construction sector. The weights of the criteria have been estimated by involving competent experts with chi-square test employed to check the degree of agreement of expert estimates. The research methodology contributes to the issue of complex evaluation of enterprise financial state and performance, while the result of the multi-criteria assessment – the ranking of enterprises and sector average with respect to financial state and performance – could be considered worth attention from business owners, potential investors, customers or other possible stakeholders.

Performance of community health workers : situating their intermediary position within complex adaptive health systems

NARCIS (Netherlands)

Kok, Maryse C; Broerse, Jacqueline E W; Theobald, Sally; Ormel, Hermen; Dieleman, Marjolein; Taegtmeyer, Miriam

2017-01-01

Health systems are social institutions, in which health worker performance is shaped by transactional processes between different actors.This analytical assessment unravels the complex web of factors that influence the performance of community health workers (CHWs) in low- and middle-income

Pitch Sequence Complexity and Long-Term Pitcher Performance

Directory of Open Access Journals (Sweden)

Joel R. Bock

2015-03-01

Full Text Available Winning one or two games during a Major League Baseball (MLB season is often the difference between a team advancing to post-season play, or “waiting until next year”. Technology advances have made it feasible to augment historical data with in-game contextual data to provide managers immediate insights regarding an opponent’s next move, thereby providing a competitive edge. We developed statistical models of pitcher behavior using pitch sequences thrown during three recent MLB seasons (2011–2013. The purpose of these models was to predict the next pitch type, for each pitcher, based on data available at the immediate moment, in each at-bat. Independent models were developed for each player’s most frequent four pitches. The overall predictability of next pitch type is 74:5%. Additional analyses on pitcher predictability within specific game situations are discussed. Finally, using linear regression analysis, we show that an index of pitch sequence predictability may be used to project player performance in terms of Earned Run Average (ERA and Fielding Independent Pitching (FIP over a longer term. On a restricted range of the independent variable, reducing complexity in selection of pitches is correlated with higher values of both FIP and ERA for the players represented in the sample. Both models were significant at the α = 0.05 level (ERA: p = 0.022; FIP: p = 0.0114. With further development, such models may reduce risk faced by management in evaluation of potential trades, or to scouts assessing unproven emerging talent. Pitchers themselves might benefit from awareness of their individual statistical tendencies, and adapt their behavior on the mound accordingly. To our knowledge, the predictive model relating pitch-wise complexity and long-term performance appears to be novel.

Performance and Complexity Co-evaluation of the Advanced Video Coding Standard for Cost-Effective Multimedia Communications

Directory of Open Access Journals (Sweden)

Saponara Sergio

2004-01-01

Full Text Available The advanced video codec (AVC standard, recently defined by a joint video team (JVT of ITU-T and ISO/IEC, is introduced in this paper together with its performance and complexity co-evaluation. While the basic framework is similar to the motion-compensated hybrid scheme of previous video coding standards, additional tools improve the compression efficiency at the expense of an increased implementation cost. As a first step to bridge the gap between the algorithmic design of a complex multimedia system and its cost-effective realization, a high-level co-evaluation approach is proposed and applied to a real-life AVC design. An exhaustive analysis of the codec compression efficiency versus complexity (memory and computational costs project space is carried out at the early algorithmic design phase. If all new coding features are used, the improved AVC compression efficiency (up to 50% compared to current video coding technology comes with a complexity increase of a factor 2 for the decoder and larger than one order of magnitude for the encoder. This represents a challenge for resource-constrained multimedia systems such as wireless devices or high-volume consumer electronics. The analysis also highlights important properties of the AVC framework allowing for complexity reduction at the high system level: when combining the new coding features, the implementation complexity accumulates, while the global compression efficiency saturates. Thus, a proper use of the AVC tools maintains the same performance as the most complex configuration while considerably reducing complexity. The reported results provide inputs to assist the profile definition in the standard, highlight the AVC bottlenecks, and select optimal trade-offs between algorithmic performance and complexity.

Effect of action verbs on the performance of a complex movement.

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Tahar Rabahi

Full Text Available The interaction between language and motor action has been approached by studying the effect of action verbs, kinaesthetic imagery and mental subtraction upon the performance of a complex movement, the squat vertical jump (SVJ. The time of flight gave the value of the height of the SVJ and was measured with an Optojump® and a Myotest® apparatuses. The results obtained by the effects of the cognitive stimuli showed a statistically significant improvement of the SVJ performance after either loudly or silently pronouncing, hearing or reading the verb saute (jump in French language. Action verbs specific for other motor actions (pince = pinch, lèche = lick or non-specific (bouge = move showed no or little effect. A meaningless verb for the French subjects (tiáo = jump in Chinese showed no effect as did rêve (dream, tombe (fall and stop. The verb gagne (win improved significantly the SVJ height, as did its antonym perds (lose suggesting a possible influence of affects in the subjects' performance. The effect of the specific action verb jump upon the heights of SVJ was similar to that obtained after kinaesthetic imagery and after mental subtraction of two digits numbers from three digits ones; possibly, in the latter, because of the intervention of language in calculus. It appears that the effects of the specific action verb jump did seem effective but not totally exclusive for the enhancement of the SVJ performance. The results imply an interaction among language and motor brain areas in the performance of a complex movement resulting in a clear specificity of the corresponding action verb. The effect upon performance may probably be influenced by the subjects' intention, increased attention and emotion produced by cognitive stimuli among which action verbs.

Simulating the Daylight Performance of Complex Fenestration Systems Using Bidirectional Scattering Distribution Functions within Radiance

Energy Technology Data Exchange (ETDEWEB)

Ward, Gregory; Mistrick, Ph.D., Richard; Lee, Eleanor; McNeil, Andrew; Jonsson, Ph.D., Jacob

2011-01-21

We describe two methods which rely on bidirectional scattering distribution functions (BSDFs) to model the daylighting performance of complex fenestration systems (CFS), enabling greater flexibility and accuracy in evaluating arbitrary assemblies of glazing, shading, and other optically-complex coplanar window systems. Two tools within Radiance enable a) efficient annual performance evaluations of CFS, and b) accurate renderings of CFS despite the loss of spatial resolution associated with low-resolution BSDF datasets for inhomogeneous systems. Validation, accuracy, and limitations of the methods are discussed.

A review of human factors challenges of complex adaptive systems: discovering and understanding chaos in human performance.

Science.gov (United States)

Karwowski, Waldemar

2012-12-01

In this paper, the author explores a need for a greater understanding of the true nature of human-system interactions from the perspective of the theory of complex adaptive systems, including the essence of complexity, emergent properties of system behavior, nonlinear systems dynamics, and deterministic chaos. Human performance, more often than not, constitutes complex adaptive phenomena with emergent properties that exhibit nonlinear dynamical (chaotic) behaviors. The complexity challenges in the design and management of contemporary work systems, including service systems, are explored. Examples of selected applications of the concepts of nonlinear dynamics to the study of human physical performance are provided. Understanding and applications of the concepts of theory of complex adaptive and dynamical systems should significantly improve the effectiveness of human-centered design efforts of a large system of systems. Performance of many contemporary work systems and environments may be sensitive to the initial conditions and may exhibit dynamic nonlinear properties and chaotic system behaviors. Human-centered design of emergent human-system interactions requires application of the theories of nonlinear dynamics and complex adaptive system. The success of future human-systems integration efforts requires the fusion of paradigms, knowledge, design principles, and methodologies of human factors and ergonomics with those of the science of complex adaptive systems as well as modern systems engineering.

ASYMMETRIC PRICE TRANSMISSION MODELING: THE IMPORTANCE OF MODEL COMPLEXITY AND THE PERFORMANCE OF THE SELECTION CRITERIA

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Henry de-Graft Acquah

2013-01-01

Full Text Available Information Criteria provides an attractive basis for selecting the best model from a set of competing asymmetric price transmission models or theories. However, little is understood about the sensitivity of the model selection methods to model complexity. This study therefore fits competing asymmetric price transmission models that differ in complexity to simulated data and evaluates the ability of the model selection methods to recover the true model. The results of Monte Carlo experimentation suggest that in general BIC, CAIC and DIC were superior to AIC when the true data generating process was the standard error correction model, whereas AIC was more successful when the true model was the complex error correction model. It is also shown that the model selection methods performed better in large samples for a complex asymmetric data generating process than with a standard asymmetric data generating process. Except for complex models, AIC's performance did not make substantial gains in recovery rates as sample size increased. The research findings demonstrate the influence of model complexity in asymmetric price transmission model comparison and selection.

Circadian Effects on Simple Components of Complex Task Performance

Science.gov (United States)

Clegg, Benjamin A.; Wickens, Christopher D.; Vieane, Alex Z.; Gutzwiller, Robert S.; Sebok, Angelia L.

2015-01-01

The goal of this study was to advance understanding and prediction of the impact of circadian rhythm on aspects of complex task performance during unexpected automation failures, and subsequent fault management. Participants trained on two tasks: a process control simulation, featuring automated support; and a multi-tasking platform. Participants then completed one task in a very early morning (circadian night) session, and the other during a late afternoon (circadian day) session. Small effects of time of day were seen on simple components of task performance, but impacts on more demanding components, such as those that occur following an automation failure, were muted relative to previous studies where circadian rhythm was compounded with sleep deprivation and fatigue. Circadian low participants engaged in compensatory strategies, rather than passively monitoring the automation. The findings and implications are discussed in the context of a model that includes the effects of sleep and fatigue factors.

Economic Complexity and Human Development: DEA performance measurement in Asia and Latin America

OpenAIRE

Ferraz, Diogo; Moralles, Hérick Fernando; Suarez Campoli, Jéssica; Ribeiro de Oliveira, Fabíola Cristina; do Nascimento Rebelatto, Daisy Aparecida

2018-01-01

Economic growth is not the unique factor to explain human development. Due to that many authors have prioritized studies to measure the Human Development Index. However, these indices do not analyze how Economic Complexity can increase Human Development. The aim of this paper is to determine the efficiency of a set of nations from Latin America and Asia, to measure a country’s performance in converting Economic Complexity into Human Development, between 2010 and 2014. The method used was Data...

Soft plasma electrolysis with complex ions for optimizing electrochemical performance

Science.gov (United States)

Kamil, Muhammad Prisla; Kaseem, Mosab; Ko, Young Gun

2017-03-01

Plasma electrolytic oxidation (PEO) was a promising surface treatment for light metals to tailor an oxide layer with excellent properties. However, porous coating structure was generally exhibited due to excessive plasma discharges, restraining its performance. The present work utilized ethylenediaminetetraacetic acid (EDTA) and Cu-EDTA complexing agents as electrolyte additives that alter the plasma discharges to improve the electrochemical properties of Al-1.1Mg alloy coated by PEO. To achieve this purpose, PEO coatings were fabricated under an alternating current in silicate electrolytes containing EDTA and Cu-EDTA. EDTA complexes were found to modify the plasma discharging behaviour during PEO that led to a lower porosity than that without additives. This was attributed to a more homogeneous electrical field throughout the PEO process while the coating growth would be maintained by an excess of dissolved Al due to the EDTA complexes. When Cu-EDTA was used, the number of discharge channels in the coating layer was lower than that with EDTA due to the incorporation of Cu2O and CuO altering the dielectric behaviour. Accordingly, the sample in the electrolyte containing Cu-EDTA constituted superior corrosion resistance to that with EDTA. The electrochemical mechanism for excellent corrosion protection was elucidated in the context of equivalent circuit model.

Analyzing complex wake-terrain interactions and its implications on wind-farm performance.

Science.gov (United States)

Tabib, Mandar; Rasheed, Adil; Fuchs, Franz

2016-09-01

Rotating wind turbine blades generate complex wakes involving vortices (helical tip-vortex, root-vortex etc.).These wakes are regions of high velocity deficits and high turbulence intensities and they tend to degrade the performance of down-stream turbines. Hence, a conservative inter-turbine distance of up-to 10 times turbine diameter (10D) is sometimes used in wind-farm layout (particularly in cases of flat terrain). This ensures that wake-effects will not reduce the overall wind-farm performance, but this leads to larger land footprint for establishing a wind-farm. In-case of complex-terrain, within a short distance (say 10D) itself, the nearby terrain can rise in altitude and be high enough to influence the wake dynamics. This wake-terrain interaction can happen either (a) indirectly, through an interaction of wake (both near tip vortex and far wake large-scale vortex) with terrain induced turbulence (especially, smaller eddies generated by small ridges within the terrain) or (b) directly, by obstructing the wake-region partially or fully in its flow-path. Hence, enhanced understanding of wake- development due to wake-terrain interaction will help in wind farm design. To this end the current study involves: (1) understanding the numerics for successful simulation of vortices, (2) understanding fundamental vortex-terrain interaction mechanism through studies devoted to interaction of a single vortex with different terrains, (3) relating influence of vortex-terrain interactions to performance of a wind-farm by studying a multi-turbine wind-farm layout under different terrains. The results on interaction of terrain and vortex has shown a much faster decay of vortex for complex terrain compared to a flatter-terrain. The potential reasons identified explaining the observation are (a) formation of secondary vortices in flow and its interaction with the primary vortex and (b) enhanced vorticity diffusion due to increased terrain-induced turbulence. The implications of

Ligand effect on the performance of organic light-emitting diodes based on europium complexes

International Nuclear Information System (INIS)

Fang Junfeng; You Han; Gao Jia; Lu Wu; Ma Dongge

2007-01-01

A series of europium complexes were synthesized and their electroluminescent (EL) characteristics were studied. It was found by comparison that the different substituted groups, such as methyl, chlorine, and nitryl, on ligand 1,10-phenanthroline affect significantly the EL performance of devices based on these complexes. The more methyl-substituted groups on ligand 1,10-phenanthroline led to higher device efficiency. A chlorine-substituted group showed the approximate EL performance as two methyl-substituted groups, whereas a nitryl substituent reduced significantly the EL luminous efficiency. However, β-diketonate ligand TTA and DBM exhibited similar EL performance. The improved EL luminous efficiency by proper substituted groups on the 1,10-phenanthroline was attributed to the reduction of the energy loss caused by light hydrogen atom vibration, as well as concentration quenching caused by intermolecular interaction, and the match of energy level between the ligand and Eu 3+

High-performance liquid chromatography of metal complexes of pheophytins a and b

International Nuclear Information System (INIS)

Brykina, G.D.; Lazareva, E.E.; Uvarova, M.I.; Shpigun, O.A.

1997-01-01

Cu(2), Zn(2), Pb(2), Hg(2), and Ce(4) complexes of phenophytins a and b were synthesized. The chromatographic retention parameters of pheophytins a and b, chlorophylls a and b, and the above complexes were determined under conditions of normal-phase and reversed-phase high-performance liquid chromatography (HPLC). The adsorption of metal pheophytinates in the hexane-n-butanol (96:4)-Silasorb 600 and acetonitrile-ethanol-acetic acid (40:40:16)-Nucleosil C 18 systems was studied by HPLC. Factors that affect the chromatographic and adsorption characteristics of compounds (structural differences between pheophytinates of the a and b series, the nature of the central metal atom, and the nature of the mobile and stationary phases) are discussed. It is demonstrated that pheophytins a and b their metal complexes can be identified and quantiatively determined by HPLC in the concentration range (0.6-44.0)[10 -6 M

High performance ultrasonic field simulation on complex geometries

Science.gov (United States)

Chouh, H.; Rougeron, G.; Chatillon, S.; Iehl, J. C.; Farrugia, J. P.; Ostromoukhov, V.

2016-02-01

Ultrasonic field simulation is a key ingredient for the design of new testing methods as well as a crucial step for NDT inspection simulation. As presented in a previous paper [1], CEA-LIST has worked on the acceleration of these simulations focusing on simple geometries (planar interfaces, isotropic materials). In this context, significant accelerations were achieved on multicore processors and GPUs (Graphics Processing Units), bringing the execution time of realistic computations in the 0.1 s range. In this paper, we present recent works that aim at similar performances on a wider range of configurations. We adapted the physical model used by the CIVA platform to design and implement a new algorithm providing a fast ultrasonic field simulation that yields nearly interactive results for complex cases. The improvements over the CIVA pencil-tracing method include adaptive strategies for pencil subdivisions to achieve a good refinement of the sensor geometry while keeping a reasonable number of ray-tracing operations. Also, interpolation of the times of flight was used to avoid time consuming computations in the impulse response reconstruction stage. To achieve the best performance, our algorithm runs on multi-core superscalar CPUs and uses high performance specialized libraries such as Intel Embree for ray-tracing, Intel MKL for signal processing and Intel TBB for parallelization. We validated the simulation results by comparing them to the ones produced by CIVA on identical test configurations including mono-element and multiple-element transducers, homogeneous, meshed 3D CAD specimens, isotropic and anisotropic materials and wave paths that can involve several interactions with interfaces. We show performance results on complete simulations that achieve computation times in the 1s range.

42 CFR 493.1467 - Condition: Laboratories performing high complexity testing; cytology general supervisor.

Science.gov (United States)

2010-10-01

... testing; cytology general supervisor. 493.1467 Section 493.1467 Public Health CENTERS FOR MEDICARE....1467 Condition: Laboratories performing high complexity testing; cytology general supervisor. For the subspecialty of cytology, the laboratory must have a general supervisor who meets the qualification...

Influence of step complexity and presentation style on step performance of computerized emergency operating procedures

Energy Technology Data Exchange (ETDEWEB)

Xu Song [Department of Industrial Engineering, Tsinghua University, Beijing 100084 (China); Li Zhizhong [Department of Industrial Engineering, Tsinghua University, Beijing 100084 (China)], E-mail: zzli@tsinghua.edu.cn; Song Fei; Luo Wei; Zhao Qianyi; Salvendy, Gavriel [Department of Industrial Engineering, Tsinghua University, Beijing 100084 (China)

2009-02-15

With the development of information technology, computerized emergency operating procedures (EOPs) are taking the place of paper-based ones. However, ergonomics issues of computerized EOPs have not been studied adequately since the industrial practice is quite limited yet. This study examined the influence of step complexity and presentation style of EOPs on step performance. A simulated computerized EOP system was developed in two presentation styles: Style A: one- and two-dimensional flowcharts combination; Style B: two-dimensional flowchart and success logic tree combination. Step complexity was quantified by a complexity measure model based on an entropy concept. Forty subjects participated in the experiment of EOP execution using the simulated system. The results of data analysis on the experiment data indicate that step complexity and presentation style could significantly influence step performance (both step error rate and operation time). Regression models were also developed. The regression analysis results imply that operation time of a step could be well predicted by step complexity while step error rate could only partly predicted by it. The result of a questionnaire investigation implies that step error rate was influenced not only by the operation task itself but also by other human factors. These findings may be useful for the design and assessment of computerized EOPs.

Wind turbine power performance verification in complex terrain and wind farms

Energy Technology Data Exchange (ETDEWEB)

Friis Pedersen, T.; Gjerding, S.; Ingham, P.; Enevoldsen, P.; Kjaer Hansen, J.; Kanstrup Joergensen, H.

2002-04-01

The IEC/EN 61400-12 Ed 1 standard for wind turbine power performance testing is being revised. The standard will be divided into four documents. The first one of these is more or less a revision of the existing document on power performance measurements on individual wind turbines. The second one is a power performance verification procedure for individual wind turbines. The third is a power performance measurement procedure of whole wind farms, and the fourth is a power performance measurement procedure for non-grid (small) wind turbines. This report presents work that was made to support the basis for this standardisation work. The work addressed experience from several national and international research projects and contractual and field experience gained within the wind energy community on this matter. The work was wide ranging and addressed 'grey' areas of knowledge regarding existing methodologies, which has then been investigated in more detail. The work has given rise to a range of conclusions and recommendations regarding: guaranties on power curves in complex terrain; investors and bankers experience with verification of power curves; power performance in relation to regional correction curves for Denmark; anemometry and the influence of inclined flow. (au)

Managing project complexity : A study into adapting early project phases to improve project performance in large engineering projects

NARCIS (Netherlands)

Bosch-Rekveldt, M.G.C.

2011-01-01

Engineering projects become increasingly more complex and project complexity is assumed to be one of the causes for projects being delivered late and over budget. However, what this project complexity actually comprised of was unclear. To improve the overall project performance, this study focuses

Radioactive Waste Management Complex low-level waste radiological performance assessment

Energy Technology Data Exchange (ETDEWEB)

Maheras, S.J.; Rood, A.S.; Magnuson, S.O.; Sussman, M.E.; Bhatt, R.N.

1994-04-01

This report documents the projected radiological dose impacts associated with the disposal of radioactive low-level waste at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. This radiological performance assessment was conducted to evaluate compliance with applicable radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the public and the environment. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses were made for both offsite receptors and individuals inadvertently intruding onto the site after closure. In addition, uncertainty and sensitivity analyses were performed. The results of the analyses indicate compliance with established radiological criteria and provide reasonable assurance that public health and safety will be protected.

Radioactive Waste Management Complex low-level waste radiological performance assessment

International Nuclear Information System (INIS)

Maheras, S.J.; Rood, A.S.; Magnuson, S.O.; Sussman, M.E.; Bhatt, R.N.

1994-04-01

This report documents the projected radiological dose impacts associated with the disposal of radioactive low-level waste at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. This radiological performance assessment was conducted to evaluate compliance with applicable radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the public and the environment. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses were made for both offsite receptors and individuals inadvertently intruding onto the site after closure. In addition, uncertainty and sensitivity analyses were performed. The results of the analyses indicate compliance with established radiological criteria and provide reasonable assurance that public health and safety will be protected

Impact of the motion and visual complexity of the background on players' performance in video game-like displays.

Science.gov (United States)

Caroux, Loïc; Le Bigot, Ludovic; Vibert, Nicolas

2013-01-01

The visual interfaces of virtual environments such as video games often show scenes where objects are superimposed on a moving background. Three experiments were designed to better understand the impact of the complexity and/or overall motion of two types of visual backgrounds often used in video games on the detection and use of superimposed, stationary items. The impact of background complexity and motion was assessed during two typical video game tasks: a relatively complex visual search task and a classic, less demanding shooting task. Background motion impaired participants' performance only when they performed the shooting game task, and only when the simplest of the two backgrounds was used. In contrast, and independently of background motion, performance on both tasks was impaired when the complexity of the background increased. Eye movement recordings demonstrated that most of the findings reflected the impact of low-level features of the two backgrounds on gaze control.

How students process equations in solving quantitative synthesis problems? Role of mathematical complexity in students’ mathematical performance

Directory of Open Access Journals (Sweden)

Bashirah Ibrahim

2017-10-01

Full Text Available We examine students’ mathematical performance on quantitative “synthesis problems” with varying mathematical complexity. Synthesis problems are tasks comprising multiple concepts typically taught in different chapters. Mathematical performance refers to the formulation, combination, and simplification of equations. Generally speaking, formulation and combination of equations require conceptual reasoning; simplification of equations requires manipulation of equations as computational tools. Mathematical complexity is operationally defined by the number and the type of equations to be manipulated concurrently due to the number of unknowns in each equation. We use two types of synthesis problems, namely, sequential and simultaneous tasks. Sequential synthesis tasks require a chronological application of pertinent concepts, and simultaneous synthesis tasks require a concurrent application of the pertinent concepts. A total of 179 physics major students from a second year mechanics course participated in the study. Data were collected from written tasks and individual interviews. Results show that mathematical complexity negatively influences the students’ mathematical performance on both types of synthesis problems. However, for the sequential synthesis tasks, it interferes only with the students’ simplification of equations. For the simultaneous synthesis tasks, mathematical complexity additionally impedes the students’ formulation and combination of equations. Several reasons may explain this difference, including the students’ different approaches to the two types of synthesis problems, cognitive load, and the variation of mathematical complexity within each synthesis type.

Collaborative crew performance in complex operational systems: L'Efficacité du travail en équipage dans des systèmes opérationnel complexes

National Research Council Canada - National Science Library

1999-01-01

.... As we progress towards the next millennium, complex operations will increasingly require consideration and integration of the collaborative element wherein crew performance becomes a critical factor for success...

Enhancing the Photovoltaic Performance of Perovskite Solar Cells with a Down-Conversion Eu-Complex.

Science.gov (United States)

Jiang, Ling; Chen, Wangchao; Zheng, Jiawei; Zhu, Liangzheng; Mo, Li'e; Li, Zhaoqian; Hu, Linhua; Hayat, Tasawar; Alsaedi, Ahmed; Zhang, Changneng; Dai, Songyuan

2017-08-16

Organometal halide perovskite solar cells (PSCs) have shown high photovoltaic performance but poor utilization of ultraviolet (UV) irradiation. Lanthanide complexes have a wide absorption range in the UV region and they can down-convert the absorbed UV light into visible light, which provides a possibility for PSCs to utilize UV light for higher photocurrent, efficiency, and stability. In this study, we use a transparent luminescent down-converting layer (LDL) of Eu-4,7-diphenyl-1,10-phenanthroline (Eu-complex) to improve the light utilization efficiency of PSCs. Compared with the uncoated PSC, the PSC coated with Eu-complex LDL on the reverse of the fluorine-doped tin oxide glass displayed an enhancement of 11.8% in short-circuit current density (J sc ) and 15.3% in efficiency due to the Eu-complex LDL re-emitting UV light (300-380 nm) in the visible range. It is indicated that the Eu-complex LDL plays the role of enhancing the power conversion efficiency as well as reducing UV degradation for PSCs.

The Impact of Technology, Job Complexity and Religious Orientation on Managerial Performance

Directory of Open Access Journals (Sweden)

Jesmin Islam

2011-12-01

Full Text Available This paper explores the impact of technology, job complexity and religious orientation on the performance of managers in the financial services industries. Data were collected from bank managers representing Islamic and conventional banks in Bangladesh. Path models were used to analyse the data. The results provide supportfor the hypothesis that a management accounting systems (MAS adequacy gap exists in the financial sector in a developing country such as Bangladesh. These Islamic and conventional banks also experienced varied outcomes regarding the impact of the MAS adequacy gap on managerial effectiveness. Significant results emerged concerning the direct influence of technology and job complexity on managerial effectiveness, although these findings again differed across religious and conventional banks. Significant intervening effects of both MAS adequacy gap and job complexity on the relationships between contingency factors and managers' effectiveness were also found. Overall the findings showed that the type of religious orientation in Islamic banks wielded an important influence on the sensitivity of the MAS adequacy gap. Religious orientation served as a control device for the relationships between job-related contingency factors andmanagerial effectiveness.

Task complexity and task, goal, and reward interdependence in group performance : a prescriptive model

NARCIS (Netherlands)

Vijfeijken, van H.T.G.A.; Kleingeld, P.A.M.; Tuijl, van H.F.J.M.; Algera, J.A.; Thierry, H.

2002-01-01

A prescriptive model on how to design effective combinations of goal setting and contingent rewards for group performance management is presented. The model incorporates the constructs task complexity, task interdependence, goal interdependence, and reward interdependence and specifies optimal fit

Modeling and Performance Considerations for Automated Fault Isolation in Complex Systems

Science.gov (United States)

Ferrell, Bob; Oostdyk, Rebecca

2010-01-01

The purpose of this paper is to document the modeling considerations and performance metrics that were examined in the development of a large-scale Fault Detection, Isolation and Recovery (FDIR) system. The FDIR system is envisioned to perform health management functions for both a launch vehicle and the ground systems that support the vehicle during checkout and launch countdown by using suite of complimentary software tools that alert operators to anomalies and failures in real-time. The FDIR team members developed a set of operational requirements for the models that would be used for fault isolation and worked closely with the vendor of the software tools selected for fault isolation to ensure that the software was able to meet the requirements. Once the requirements were established, example models of sufficient complexity were used to test the performance of the software. The results of the performance testing demonstrated the need for enhancements to the software in order to meet the demands of the full-scale ground and vehicle FDIR system. The paper highlights the importance of the development of operational requirements and preliminary performance testing as a strategy for identifying deficiencies in highly scalable systems and rectifying those deficiencies before they imperil the success of the project

Performance of community health workers: situating their intermediary position within complex adaptive health systems.

Science.gov (United States)

Kok, Maryse C; Broerse, Jacqueline E W; Theobald, Sally; Ormel, Hermen; Dieleman, Marjolein; Taegtmeyer, Miriam

2017-09-02

Health systems are social institutions, in which health worker performance is shaped by transactional processes between different actors.This analytical assessment unravels the complex web of factors that influence the performance of community health workers (CHWs) in low- and middle-income countries. It examines their unique intermediary position between the communities they serve and actors in the health sector, and the complexity of the health systems in which they operate. The assessment combines evidence from the international literature on CHW programmes with research outcomes from the 5-year REACHOUT consortium, undertaking implementation research to improve CHW performance in six contexts (two in Asia and four in Africa). A conceptual framework on CHW performance, which explicitly conceptualizes the interface role of CHWs, is presented. Various categories of factors influencing CHW performance are distinguished in the framework: the context, the health system and intervention hardware and the health system and intervention software. Hardware elements of CHW interventions comprise the supervision systems, training, accountability and communication structures, incentives, supplies and logistics. Software elements relate to the ideas, interests, relationships, power, values and norms of the health system actors. They influence CHWs' feelings of connectedness, familiarity, self-fulfilment and serving the same goals and CHWs' perceptions of support received, respect, competence, honesty, fairness and recognition.The framework shines a spotlight on the need for programmes to pay more attention to ideas, interests, relationships, power, values and norms of CHWs, communities, health professionals and other actors in the health system, if CHW performance is to improve.

Spoken commands control robot that handles radioactive materials

International Nuclear Information System (INIS)

Phelan, P.F.; Keddy, C.; Beugelsdojk, T.J.

1989-01-01

Several robotic systems have been developed by Los Alamos National Laboratory to handle radioactive material. Because of safety considerations, the robotic system must be under direct human supervision and interactive control continuously. In this paper, we describe the implementation of a voice-recognition system that permits this control, yet allows the robot to perform complex preprogrammed manipulations without the operator's intervention. To provide better interactive control, we connected to the robot's control computer, a speech synthesis unit, which provides audible feedback to the operator. Thus upon completion of a task or if an emergency arises, an appropriate spoken message can be reported by the control computer. The training programming and operation of this commercially available system are discussed, as are the practical problems encountered during operations

Model Complexity and Out-of-Sample Performance: Evidence from S&P 500 Index Returns

NARCIS (Netherlands)

Kaeck, Andreas; Rodrigues, Paulo; Seeger, Norman J.

We apply a range of out-of-sample specification tests to more than forty competing stochastic volatility models to address how model complexity affects out-of-sample performance. Using daily S&P 500 index returns, model confidence set estimations provide strong evidence that the most important model

A complex symbol signal-to-noise ratio estimator and its performance

Science.gov (United States)

Feria, Y.

1994-01-01

This article presents an algorithm for estimating the signal-to-noise ratio (SNR) of signals that contain data on a downconverted suppressed carrier or the first harmonic of a square-wave subcarrier. This algorithm can be used to determine the performance of the full-spectrum combiner for the Galileo S-band (2.2- to 2.3-GHz) mission by measuring the input and output symbol SNR. A performance analysis of the algorithm shows that the estimator can estimate the complex symbol SNR using 10,000 symbols at a true symbol SNR of -5 dB with a mean of -4.9985 dB and a standard deviation of 0.2454 dB, and these analytical results are checked by simulations of 100 runs with a mean of -5.06 dB and a standard deviation of 0.2506 dB.

BETWEEN PARCIMONY AND COMPLEXITY: COMPARING PERFORMANCE MEASURES FOR ROMANIAN BANKING INSTITUTIONS

Directory of Open Access Journals (Sweden)

ANCA MUNTEANU

2012-01-01

Full Text Available The main objective of this study is to establish the relationship between traditional measures of performance (ROE, ROA and NIM and EVA in order to gain some insight about the relevance of using more sophisticated performance measurements tools. Towards this end the study uses two acknowledged statistical measures: Kendall’s Tau and Spearman rank correlation Index. Using data from 12 Romanian banking institutions that report under IFRS for the period 2006-2010 the results suggest that generally EVA is highly correlated with Residual Income in the years that present positive operational profits whereas for the years with negative outcome the correlation is low. ROA and ROE are the measure that best correlates with EVA for the entire period and thus -applying Occam’s razor- could be used as a substitute for more complex shareholder earnings measures.

Integrated modeling tool for performance engineering of complex computer systems

Science.gov (United States)

Wright, Gary; Ball, Duane; Hoyt, Susan; Steele, Oscar

1989-01-01

This report summarizes Advanced System Technologies' accomplishments on the Phase 2 SBIR contract NAS7-995. The technical objectives of the report are: (1) to develop an evaluation version of a graphical, integrated modeling language according to the specification resulting from the Phase 2 research; and (2) to determine the degree to which the language meets its objectives by evaluating ease of use, utility of two sets of performance predictions, and the power of the language constructs. The technical approach followed to meet these objectives was to design, develop, and test an evaluation prototype of a graphical, performance prediction tool. The utility of the prototype was then evaluated by applying it to a variety of test cases found in the literature and in AST case histories. Numerous models were constructed and successfully tested. The major conclusion of this Phase 2 SBIR research and development effort is that complex, real-time computer systems can be specified in a non-procedural manner using combinations of icons, windows, menus, and dialogs. Such a specification technique provides an interface that system designers and architects find natural and easy to use. In addition, PEDESTAL's multiview approach provides system engineers with the capability to perform the trade-offs necessary to produce a design that meets timing performance requirements. Sample system designs analyzed during the development effort showed that models could be constructed in a fraction of the time required by non-visual system design capture tools.

A model of R-D performance evaluation for Rate-Distortion-Complexity evaluation of H.264 video coding

DEFF Research Database (Denmark)

Wu, Mo; Forchhammer, Søren

2007-01-01

This paper considers a method for evaluation of Rate-Distortion-Complexity (R-D-C) performance of video coding. A statistical model of the transformed coefficients is used to estimate the Rate-Distortion (R-D) performance. A model frame work for rate, distortion and slope of the R-D curve for inter...... and intra frame is presented. Assumptions are given for analyzing an R-D model for fast R-D-C evaluation. The theoretical expressions are combined with H.264 video coding, and confirmed by experimental results. The complexity frame work is applied to the integer motion estimation....

Comparative Visual Analysis of Structure-Performance Relations in Complex Bulk-Heterojunction Morphologies

KAUST Repository

Aboulhassan, A.

2017-07-04

The structure of Bulk-Heterojunction (BHJ) materials, the main component of organic photovoltaic solar cells, is very complex, and the relationship between structure and performance is still largely an open question. Overall, there is a wide spectrum of fabrication configurations resulting in different BHJ morphologies and correspondingly different performances. Current state-of-the-art methods for assessing the performance of BHJ morphologies are either based on global quantification of morphological features or simply on visual inspection of the morphology based on experimental imaging. This makes finding optimal BHJ structures very challenging. Moreover, finding the optimal fabrication parameters to get an optimal structure is still an open question. In this paper, we propose a visual analysis framework to help answer these questions through comparative visualization and parameter space exploration for local morphology features. With our approach, we enable scientists to explore multivariate correlations between local features and performance indicators of BHJ morphologies. Our framework is built on shape-based clustering of local cubical regions of the morphology that we call patches. This enables correlating the features of clusters with intuition-based performance indicators computed from geometrical and topological features of charge paths.

Comparative Visual Analysis of Structure-Performance Relations in Complex Bulk-Heterojunction Morphologies

KAUST Repository

Aboulhassan, A.; Sicat, R.; Baum, D.; Wodo, O.; Hadwiger, Markus

2017-01-01

The structure of Bulk-Heterojunction (BHJ) materials, the main component of organic photovoltaic solar cells, is very complex, and the relationship between structure and performance is still largely an open question. Overall, there is a wide spectrum of fabrication configurations resulting in different BHJ morphologies and correspondingly different performances. Current state-of-the-art methods for assessing the performance of BHJ morphologies are either based on global quantification of morphological features or simply on visual inspection of the morphology based on experimental imaging. This makes finding optimal BHJ structures very challenging. Moreover, finding the optimal fabrication parameters to get an optimal structure is still an open question. In this paper, we propose a visual analysis framework to help answer these questions through comparative visualization and parameter space exploration for local morphology features. With our approach, we enable scientists to explore multivariate correlations between local features and performance indicators of BHJ morphologies. Our framework is built on shape-based clustering of local cubical regions of the morphology that we call patches. This enables correlating the features of clusters with intuition-based performance indicators computed from geometrical and topological features of charge paths.

Innovation in user-centered skills and performance improvement for sustainable complex service systems.

Science.gov (United States)

Karwowski, Waldemar; Ahram, Tareq Z

2012-01-01

In order to leverage individual and organizational learning and to remain competitive in current turbulent markets it is important for employees, managers, planners and leaders to perform at high levels over time. Employee competence and skills are extremely important matters in view of the general shortage of talent and the mobility of employees with talent. Two factors emerged to have the greatest impact on the competitiveness of complex service systems: improving managerial and employee's knowledge attainment for skills, and improving the training and development of the workforce. This paper introduces the knowledge-based user-centered service design approach for sustainable skill and performance improvement in education, design and modeling of the next generation of complex service systems. The rest of the paper cover topics in human factors and sustainable business process modeling for the service industry, and illustrates the user-centered service system development cycle with the integration of systems engineering concepts in service systems. A roadmap for designing service systems of the future is discussed. The framework introduced in this paper is based on key user-centered design principles and systems engineering applications to support service competitiveness.

The COMPASS Tokamak Plasma Control Software Performance

Science.gov (United States)

Valcarcel, Daniel F.; Neto, André; Carvalho, Ivo S.; Carvalho, Bernardo B.; Fernandes, Horácio; Sousa, Jorge; Janky, Filip; Havlicek, Josef; Beno, Radek; Horacek, Jan; Hron, Martin; Panek, Radomir

2011-08-01

The COMPASS tokamak has began operation at the IPP Prague in December 2008. A new control system has been built using an ATCA-based real-time system developed at IST Lisbon. The control software is implemented on top of the MARTe real-time framework attaining control cycles as short as 50 μs, with a jitter of less than 1 μs. The controlled parameters, important for the plasma performance, are the plasma current, position of the plasma current center, boundary shape and horizontal and vertical velocities. These are divided in two control cycles: slow at 500 μs and fast at 50 μs. The project has two phases. First, the software implements a digital controller, similar to the analog one used during the COMPASS-D operation in Culham. In the slow cycle, the plasma current and position are measured and controlled with PID and feedforward controllers, respectively, the shaping magnetic field is preprogrammed. The vertical instability and horizontal equilibrium are controlled with the faster 50-μs cycle PID controllers. The second phase will implement a plasma-shape reconstruction algorithm and controller, aiming at optimized plasma performance. The system was designed to be as modular as possible by breaking the functional requirements of the control system into several independent and specialized modules. This splitting enabled tuning the execution of each system part and to use the modules in a variety of applications with different time constraints. This paper presents the design and overall performance of the COMPASS control software.

On improving the performance of nonphotochemical quenching in CP29 light-harvesting antenna complex

Science.gov (United States)

Berman, Gennady P.; Nesterov, Alexander I.; Sayre, Richard T.; Still, Susanne

2016-03-01

We model and simulate the performance of charge-transfer in nonphotochemical quenching (NPQ) in the CP29 light-harvesting antenna-complex associated with photosystem II (PSII). The model consists of five discrete excitonic energy states and two sinks, responsible for the potentially damaging processes and charge-transfer channels, respectively. We demonstrate that by varying (i) the parameters of the chlorophyll-based dimer, (ii) the resonant properties of the protein-solvent environment interaction, and (iii) the energy transfer rates to the sinks, one can significantly improve the performance of the NPQ. Our analysis suggests strategies for improving the performance of the NPQ in response to environmental changes, and may stimulate experimental verification.

Task complexity and task, goal, and reward interdependence in group performance management : A prescriptive model

NARCIS (Netherlands)

van Vijfeijken, H.; Kleingeld, A.; van Tuijl, H.; Algera, J.A.; Thierry, Hk.

2002-01-01

A prescriptive model on how to design effective combinations of goal setting and contingent rewards for group performance management is presented. The model incorporates the constructs task complexity, task interdependence, goal interdependence, and reward interdependence and specifies optimal fit

Front-office/back-office configurations and operational performance in complex health services.

Science.gov (United States)

Gemmel, Paul; van Steenis, Thomas; Meijboom, Bert

2014-01-01

Acquired brain injury (ABI) occurs from various causes at different ages and leads to many different types of healthcare needs. Several Dutch ABI-networks installed a local co-ordination and contact point (CCP) which functions as a central and easily accessible service for people to consult when they have questions related to ABI. To explore the relationship between front/back office design and operational performance by investigating the particular enquiry service provided by different CCPs for people affected by an ABI. In-depth interviews with 14 FO/BO employees from three case organizations, complemented with information from desk research and three one-day field visits. The CCPs applied different FO/BO configurations in terms of customer contact and in terms of grouping of front and/or back office activities into tasks for one employee. It is the complexity of the enquiry that determines which approach is more appropriate. For complex enquiries, the level of decoupling is high in all CCPs. This allows multiple experts to be involved in the process. For regular enquiries, CCPs have a choice: either working in the same way as in the complex enquiries or coupling FO/BO activities to be able to serve clients faster and without handovers.

Influence of complexing agents on the mechanical performances of the cement conditioning matrix

International Nuclear Information System (INIS)

Nicu, M.; Mihai, F.; Turcanu, C.

1998-01-01

The safety of the radioactive waste disposal is a priority demand concerning the protection of the environment and population. For this reason, an engineering multi-barrier system is studied in order to be improved. This study aims to establish the influence of the complexing agents on the mechanical performances of the cement conditioning matrix. Radioactive effluents which contain agents as oxalic and citric acids are generated during the radioactive decontamination operation using chemical methods. The conditioning of these wastes by cementing process imposed the experimental determination of the mechanical performances of the matrix and the upper permissible level of complexing agent concentration. To determine the influence of complexing agents on the mechanical performances of cement conditioning matrix, cubic samples (20 mm x 20 mm x 20 mm) were prepared using commercial Portland cement and solutions of organic complexing acids or salts (citric acid, oxalic acid, tartaric acid, sodium citrate and ammonium oxalate). The complexation concentration varied between 0.25% and 1% in distilled and drinking water, respectively. The selected cement/water ratio was 0.5. The experiments were focused on: - establishing the firmness of the Pa 35 cement pastes and mortars in dependence on the water/cement ratio, by classical methods (Tetmeyer probe for pastes and standard cone for mortars) and by triclinic time through a funnel with 15 mm aperture; - studying the influence of the tartaric, oxalic, citric acids, ammonium oxalate and sodium citrate solution concentrations on water quantities used to obtain pastes with normal firmness and on Pa 35 cement setting; - the influence of oxalic acid, tartaric acid and ammonium oxalate solution concentrations on the strength of compression of the pastes with normal firmness; - for testing, standard test bar cubes with 20 mm sides were used and the strength of compression was tested at 28 days; - establishing the behaviour in time of

The effects of overtime work and task complexity on the performance of nuclear plant operators: A proposed methodology

International Nuclear Information System (INIS)

Banks, W.W.; Potash, L.

1985-01-01

This document presents a very general methodology for determining the effect of overtime work and task complexity on operator performance in response to simulated out-of-limit nuclear plant conditions. The independent variables consist of three levels of overtime work and three levels of task complexity. Multiple dependent performance measures are proposed for use and discussion. Overtime work is operationally defined in terms of the number of hours worked by nuclear plant operators beyond the traditional 8 hours per shift. Task complexity is operationalized in terms of the number of operator tasks required to remedy a given plant anomalous condition and bring the plant back to a ''within limits'' or ''normal'' steady-state condition. The proposed methodology would employ a 2 factor repeated measures design along with the analysis of variance (linear) model

The Influence of Business Environmental Dynamism, Complexity and Munificence on Performance of Small and Medium Enterprises in Kenya

Directory of Open Access Journals (Sweden)

Washington Oduor Okeyo

2014-08-01

Full Text Available The main purpose of this article is to examine how business environment affects small and medium enterprises. The paper is motivated by the important contributions small and medium enterprises have in many countries, especially Kenya towards job creation, poverty reduction and economic development. Literature however argues that effectiveness of the contributions is conditioned by the state of business environmental factors such as politics, economy, socio-culture, technology, ecology and laws/regulations. Dynamism, complexity and munificence of these factors are therefore vital to achievement of organizational objectives and overall performance. Even so, a review of literature reveals contradictory views regarding the effect of these factors on performance of organizations. Furthermore, studies focusing on these factors in the Kenyan context, particularly with regard to their effect on performance of small and medium firms, are scarce. This article bridges this gap based on a study focusing on 800 manufacturing organizations in Nairobi – Kenya. A sample of 150 enterprises was selected through stratification by business sector followed by simple random sampling. The research design was cross sectional survey where data was collected using a structured questionnaire over a period of one month at the end of which 95 organizations responded giving a response rate of 64%. Reliability and validity of the instrument were determined through Cronbach’s alpha tests and expert reviews. Statistical Package for Social Sciences was used to determine normality through descriptive statistics and study hypotheses tested using inferential statistics. The study established that business environment had an overall impact on organizational performance. Specifically, dynamism, complexity and munificence each had a direct influence on the enterprises in the study. Furthermore the combined effect on performance was found to be greater than that of dynamism and

Effects of Maize Source and Complex Enzymes on Performance and Nutrient Utilization of Broilers

Directory of Open Access Journals (Sweden)

Defu Tang

2014-12-01

Full Text Available The objective of this study was to investigate the effect of maize source and complex enzymes containing amylase, xylanase and protease on performance and nutrient utilization of broilers. The experiment was a 4×3 factorial design with diets containing four source maize samples (M1, M2, M3, and M4 and without or with two kinds of complex enzyme A (Axtra XAP and B (Avizyme 1502. Nine hundred and sixty day old Arbor Acres broiler chicks were used in the trial (12 treatments with 8 replicate pens of 10 chicks. Birds fed M1 diet had better body weight gain (BWG and lower feed/gain ratio compared with those fed M3 diet and M4 diet (p0.05, respectively. The fresh feces output was significantly decreased by the addition of enzyme B (p<0.05. Maize source affects the nutrients digestibility and performance of broilers, and a combination of amylase, xylanase and protease is effective in improving the growth profiles of broilers fed maize-soybean-rapeseed-cotton mixed diets.

A series of copper complexes with carbazole and oxadiazole moieties: Synthesis, characterization and luminescence performance

Energy Technology Data Exchange (ETDEWEB)

Bai Weiyang, E-mail: baiwy02@163.com [College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054 (China); Sun Li [Graduate University of Chinese Academy of Sciences, Beijing 100049 (China)

2012-10-15

In this paper, various moieties of ethyl, carbazole and oxadiazole are attached to 2-thiazol-4-yl-1H-benzoimidazole to form a series of diamine ligands. Their corresponding Cu(I) complexes are also synthesized using bis(2-(diphenylphosphanyl)phenyl) ether as the auxiliary ligand. Crystal structures, thermal property, electronic nature and luminescence property of these Cu(I) complexes are discussed in detail. These Cu(I) complexes are found to be efficient green-emitting ones in solutions and the emissive parameters are improved largely by the incorporation of substituent moieties. Detailed analysis suggests that the effective suppression of solvent-induced exciplex quenching is responsible for this phenomenon. On the other hand, the introduction of substituent moieties exerts no obvious influence on molecular structure, thermal stability and emitting-energy of the Cu(I) complexes, owing to their absence from inner coordination sphere. - Highlights: Black-Right-Pointing-Pointer Diamine ligands with various moieties and Cu(I) complexes are synthesized. Black-Right-Pointing-Pointer Crystal structures and photophysical property are discussed in detail. Black-Right-Pointing-Pointer The incorporation of substituent moieties improves luminescence performance. Black-Right-Pointing-Pointer Solvent-induced exciplex quenching is suppressed by substituent moieties.

High-performance execution of psychophysical tasks with complex visual stimuli in MATLAB

Science.gov (United States)

Asaad, Wael F.; Santhanam, Navaneethan; McClellan, Steven

2013-01-01

Behavioral, psychological, and physiological experiments often require the ability to present sensory stimuli, monitor and record subjects' responses, interface with a wide range of devices, and precisely control the timing of events within a behavioral task. Here, we describe our recent progress developing an accessible and full-featured software system for controlling such studies using the MATLAB environment. Compared with earlier reports on this software, key new features have been implemented to allow the presentation of more complex visual stimuli, increase temporal precision, and enhance user interaction. These features greatly improve the performance of the system and broaden its applicability to a wider range of possible experiments. This report describes these new features and improvements, current limitations, and quantifies the performance of the system in a real-world experimental setting. PMID:23034363

A (Small) complexity performance contest: SPT versus LBFS

DEFF Research Database (Denmark)

Nielsen, Erland Hejn

2002-01-01

When discussing the nature of loading rules relevant to continuous dynamic job/flow shop systems, the general understanding is that results obtained in simpler structures of 2 to 4 machines are invariant to scaling and can be generalised without problems to more complex structures. The SPT...... results on pure re-entrant flow shop structures emerges. It now seems that alternative loading rules as for instance the LBFS (Last Buffer First Served) due to its strong long run stabilising property attracts quite some interest. To be more precise about the complexity aspect, complexity in job...... are not entirely only of theoretical interest, as well as results from a standard serial job/flow shop set-up, but with resource limitations that prevent the independent operations of the individual stations in the system....

A (Small) Complexity Performance Contest: SPT versus LBFS

DEFF Research Database (Denmark)

Nielsen, Erland Hejn

2002-01-01

When discussing the nature of loading rules relevant to continuous dynamic job/flow shop systems, the general understanding is that results obtained in simpler structures of 2 to 4 machines are invariant to scaling and can be generalised without problems to more complex structures. The SPT...... results on pure re-entrant flow shop structures emerges. It now seems that alternative loading rules as for instance the LBFS (Last Buffer First Served) due to its strong long run stabilising property attracts quite some interest. To be more precise about the complexity aspect, complexity in job...... are not entirely only of theoretical interest, as well as results from a standard serial job/flow shop set-up, but with resource limitations that prevent the independent operations of the individual stations in the system....

A Low-Complexity and High-Performance 2D Look-Up Table for LDPC Hardware Implementation

Science.gov (United States)

Chen, Jung-Chieh; Yang, Po-Hui; Lain, Jenn-Kaie; Chung, Tzu-Wen

In this paper, we propose a low-complexity, high-efficiency two-dimensional look-up table (2D LUT) for carrying out the sum-product algorithm in the decoding of low-density parity-check (LDPC) codes. Instead of employing adders for the core operation when updating check node messages, in the proposed scheme, the main term and correction factor of the core operation are successfully merged into a compact 2D LUT. Simulation results indicate that the proposed 2D LUT not only attains close-to-optimal bit error rate performance but also enjoys a low complexity advantage that is suitable for hardware implementation.

Effects of Task Performance and Task Complexity on the Validity of Computational Models of Attention

NARCIS (Netherlands)

Koning, L. de; Maanen, P.P. van; Dongen, K. van

2008-01-01

Computational models of attention can be used as a component of decision support systems. For accurate support, a computational model of attention has to be valid and robust. The effects of task performance and task complexity on the validity of three different computational models of attention were

The Impact of Environmental Complexity and Team Training on Team Processes and Performance in Multi-Team Environments

National Research Council Canada - National Science Library

Cobb, Marshall

1999-01-01

This study examined how manipulating the level of environmental complexity and the type of team training given to subject volunteers impacted important team process behaviors and performance outcomes...

Profiles of Motor Laterality in Young Athletes' Performance of Complex Movements: Merging the MOTORLAT and PATHoops Tools

Science.gov (United States)

Castañer, Marta; Andueza, Juan; Hileno, Raúl; Puigarnau, Silvia; Prat, Queralt; Camerino, Oleguer

2018-01-01

Laterality is a key aspect of the analysis of basic and specific motor skills. It is relevant to sports because it involves motor laterality profiles beyond left-right preference and spatial orientation of the body. The aim of this study was to obtain the laterality profiles of young athletes, taking into account the synergies between the support and precision functions of limbs and body parts in the performance of complex motor skills. We applied two instruments: (a) MOTORLAT, a motor laterality inventory comprising 30 items of basic, specific, and combined motor skills, and (b) the Precision and Agility Tapping over Hoops (PATHoops) task, in which participants had to perform a path by stepping in each of 14 hoops arranged on the floor, allowing the observation of their feet, left-right preference and spatial orientation. A total of 96 young athletes performed the PATHoops task and the 30 MOTORLAT items, allowing us to obtain data about limb dominance and spatial orientation of the body in the performance of complex motor skills. Laterality profiles were obtained by means of a cluster analysis and a correlational analysis and a contingency analysis were applied between the motor skills and spatial orientation actions performed. The results obtained using MOTORLAT show that the combined motor skills criterion (for example, turning while jumping) differentiates athletes' uses of laterality, showing a clear tendency toward mixed laterality profiles in the performance of complex movements. In the PATHoops task, the best spatial orientation strategy was “same way” (same foot and spatial wing) followed by “opposite way” (opposite foot and spatial wing), in keeping with the research assumption that actions unfolding in a horizontal direction in front of an observer's eyes are common in a variety of sports. PMID:29930527

Performance Measurement of Complex Event Platforms

Directory of Open Access Journals (Sweden)

Eva Zámečníková

2016-12-01

Full Text Available The aim of this paper is to find and compare existing solutions of complex event processing platforms (CEP. CEP platforms generally serve for processing and/or predicting of high frequency data. We intend to use CEP platform for processing of complex time series and integrate a solution for newly proposed method of decision making. The decision making process will be described by formal grammar. As there are lots of CEP solutions we will take the following characteristics under consideration - the processing in real time, possibility of processing of high volume data from multiple sources, platform independence, platform allowing integration with user solution and open license. At first we will talk about existing CEP tools and their specific way of use in praxis. Then we will mention the design of method for formalization of business rules used for decision making. Afterwards, we focus on two platforms which seem to be the best fit for integration of our solution and we will list the main pros and cons of each approach. Next part is devoted to benchmark platforms for CEP. Final part is devoted to experimental measurements of platform with integrated method for decision support.

A swarm of autonomous miniature underwater robot drifters for exploring submesoscale ocean dynamics.

Science.gov (United States)

Jaffe, Jules S; Franks, Peter J S; Roberts, Paul L D; Mirza, Diba; Schurgers, Curt; Kastner, Ryan; Boch, Adrien

2017-01-24

Measuring the ever-changing 3-dimensional (3D) motions of the ocean requires simultaneous sampling at multiple locations. In particular, sampling the complex, nonlinear dynamics associated with submesoscales (swarm of 16 independent vehicles whose 3D trajectories are measured near-continuously, underwater. As the vehicles drift with the ambient flow or execute preprogrammed vertical behaviours, the simultaneous measurements at multiple, known locations resolve the details of the flow within the swarm. We describe the design, construction, control and underwater navigation of the M-AUE. A field programme in the coastal ocean using a swarm of these robots programmed with a depth-holding behaviour provides a unique test of a physical-biological interaction leading to plankton patch formation in internal waves. The performance of the M-AUE vehicles illustrates their novel capability for measuring submesoscale dynamics.

Three propositions on why characteristics of performance management systems converge across policy areas with different levels of task complexity

DEFF Research Database (Denmark)

Bjørnholt, Bente; Lindholst, Andrej Christian; Agger Nielsen, Jeppe

2014-01-01

of task complexity amidst a lack of formal and overarching, government-wide policies. We advance our propositions from a case study comparing the characteristics of performance management systems across social services (eldercare) and technical services (park services) in Denmark. Contrary to expectations......This article investigates the differences and similarities between performance management systems across public services. We offer three propositions as to why the characteristics of performance management systems may still converge across policy areas in the public sector with different levels...... for divergence due to differences in task complexity, the characteristics of performance management systems in the two policy areas are observed to converge. On the basis of a case study, we propose that convergence has occurred due to 1) similarities in policy-specific reforms, 2) institutional pressures, and 3...

Product Complexity Impact on Quality and Delivery Performance

OpenAIRE

Nielsen, Jeppe Bjerrum; Hvam, Lars

2011-01-01

Existing literature on product portfolio complexity is mainly focused on cost related aspects. It is widely acknowledged that an increase in a company’s product portfolio will lead to an increase in complexity related costs such as order management, procurement and inventory. The objective of this article is to examine which other factors that might be affected when a company is expanding its product portfolio, if initiatives are not taken to accommodate this increase. Empirical work carried ...

Effects of Enzyme Complex Supplementation to a Paddy-based Diet on Performance and Nutrient Digestibility of Meat-type Ducks

Directory of Open Access Journals (Sweden)

P. Kang

2013-02-01

Full Text Available Paddy rice is rarely used as a feed because of its high fiber content. In this study, two experiments were conducted to study the effects of supplementing an enzyme complex consisting of xylanase, beta-glucanase and cellulase, to paddy-based diets on the performance and nutrient digestibility in meat-type ducks. In the both experiments, meat-type ducks (Cherry Valley were randomly assigned to four treatments. Treatment 1 was a basal diet of corn-soybean; treatment 2 was a basal diet of corn-paddy-soybean; treatment 3, had enzyme complex added to the corn-paddy-soybean basal diet at levels of 0.5 g/kg diet; and treatment 4, had enzyme complex added to the corn-paddy-soybean diet at levels of 1.0 g/kg diet. The results showed that the enzyme complex increased the ADG, and decreased the ADFI and F/G significantly (p0.05. The outcome of this research indicates that the application of enzyme complex made up of xylanase, beta-glucanase, and cellulase, in the corn-paddy-soybean diet, can improve performance and nutrition digestibility in meat-type ducks.

Shifting effects in randomised controlled trials of complex interventions: a new kind of performance bias?

Science.gov (United States)

Gold, C; Erkkilä, J; Crawford, M J

2012-11-01

Randomised controlled trials (RCTs) aim to provide unbiased estimates of treatment effects. However, the process of implementing trial procedures may have an impact on the performance of complex interventions that rely strongly on the intuition and confidence of therapists. We aimed to examine whether shifting effects over the recruitment period can be observed that might indicate such impact. Three RCTs investigating music therapy vs. standard care were included. The intervention was performed by experienced therapists and based on established methods. We examined outcomes of participants graphically, analysed cumulative effects and tested for differences between first vs. later participants. We tested for potential confounding population shifts through multiple regression models. Cumulative differences suggested trends over the recruitment period. Effect sizes tended to be less favourable among the first participants than later participants. In one study, effects even changed direction. Age, gender and baseline severity did not account for these shifting effects. Some trials of complex interventions have shifting effects over the recruitment period that cannot be explained by therapist experience or shifting demographics. Replication and further research should aim to find out which interventions and trial designs are most vulnerable to this new kind of performance bias. © 2012 John Wiley & Sons A/S.

Will hypertension performance measures used for pay-for-performance programs penalize those who care for medically complex patients?

Science.gov (United States)

Petersen, Laura A; Woodard, Lechauncy D; Henderson, Louise M; Urech, Tracy H; Pietz, Kenneth

2009-06-16

There is concern that performance measures, patient ratings of their care, and pay-for-performance programs may penalize healthcare providers of patients with multiple chronic coexisting conditions. We examined the impact of coexisting conditions on the quality of care for hypertension and patient perception of overall quality of their health care. We classified 141 609 veterans with hypertension into 4 condition groups: those with hypertension-concordant (diabetes mellitus, ischemic heart disease, dyslipidemia) and/or -discordant (arthritis, depression, chronic obstructive pulmonary disease) conditions or neither. We measured blood pressure control at the index visit, overall good quality of care for hypertension, including a follow-up interval, and patient ratings of satisfaction with their care. Associations between condition type and number of coexisting conditions on receipt of overall good quality of care were assessed with logistic regression. The relationship between patient assessment and objective measures of quality was assessed. Of the cohort, 49.5% had concordant-only comorbidities, 8.7% had discordant-only comorbidities, 25.9% had both, and 16.0% had none. Odds of receiving overall good quality after adjustment for age were higher for those with concordant comorbidities (odds ratio, 1.78; 95% confidence interval, 1.70 to 1.87), discordant comorbidities (odds ratio, 1.32; 95% confidence interval, 1.23 to 1.41), or both (odds ratio, 2.25; 95% confidence interval, 2.13 to 2.38) compared with neither. Findings did not change after adjustment for illness severity and/or number of primary care and specialty care visits. Patient assessment of quality did not vary by the presence of coexisting conditions and was not related to objective ratings of quality of care. Contrary to expectations, patients with greater complexity had higher odds of receiving high-quality care for hypertension. Subjective ratings of care did not vary with the presence or absence of

Selecting a change and evaluating its impact on the performance of a complex adaptive health care delivery system

Directory of Open Access Journals (Sweden)

Malaz A Boustani

2010-05-01

Full Text Available Malaz A Boustani1,2,3,4, Stephanie Munger1,2, Rajesh Gulati3,4, Mickey Vogel4, Robin A Beck3,4, Christopher M Callahan1,2,3,41Indiana University Center for Aging Research, 2Regenstrief Institute Inc., 3Indiana University School of Medicine, Department of Medicine, Division of General Internal Medicine and Geriatrics, 4Indiana University Medical Group-Primary Care; Indianapolis, IN USAAbstract: Complexity science suggests that our current health care delivery system acts as a complex adaptive system (CAS. Such systems represent a dynamic and flexible network of individuals who can coevolve with their ever changing environment. The CAS performance fluctuates and its members’ interactions continuously change over time in response to the stress generated by its surrounding environment. This paper will review the challenges of intervening and introducing a planned change into a complex adaptive health care delivery system. We explore the role of the “reflective adaptive process” in developing delivery interventions and suggest different evaluation methodologies to study the impact of such interventions on the performance of the entire system. We finally describe the implementation of a new program, the Aging Brain Care Medical Home as a case study of our proposed evaluation process.Keywords: complexity, aging brain, implementation, complex adaptive system, sustained change, care delivery

Electrochemically fabricated polypyrrole-cobalt-oxygen coordination complex as high-performance lithium-storage materials.

Science.gov (United States)

Guo, Bingkun; Kong, Qingyu; Zhu, Ying; Mao, Ya; Wang, Zhaoxiang; Wan, Meixiang; Chen, Liquan

2011-12-23

Current lithium-ion battery (LIB) technologies are all based on inorganic electrode materials, though organic materials have been used as electrodes for years. Disadvantages such as limited thermal stability and low specific capacity hinder their applications. On the other hand, the transition metal oxides that provide high lithium-storage capacity by way of electrochemical conversion reaction suffer from poor cycling stability. Here we report a novel high-performance, organic, lithium-storage material, a polypyrrole-cobalt-oxygen (PPy-Co-O) coordination complex, with high lithium-storage capacity and excellent cycling stability. Extended X-ray absorption fine structure and Raman spectroscopy and other physical and electrochemical characterizations demonstrate that this coordination complex can be electrochemically fabricated by cycling PPy-coated Co(3)O(4) between 0.0 V and 3.0 V versus Li(+)/Li. Density functional theory (DFT) calculations indicate that each cobalt atom coordinates with two nitrogen atoms within the PPy-Co coordination layer and the layers are connected with oxygen atoms between them. Coordination weakens the C-H bonds on PPy and makes the complex a novel lithium-storage material with high capacity and high cycling stability. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Does strategy instruction on the Rey-Osterrieth Complex Figure task lead to transferred performance improvement on the Modified Taylor Complex Figure task? A randomized controlled trial in school-aged children.

Science.gov (United States)

Resch, Christine; Keulers, Esther; Martens, Rosa; van Heugten, Caroline; Hurks, Petra

2018-04-05

Providing children with organizational strategy instruction on the Rey Osterrieth Complex Figure (ROCF) has previously been found to improve organizational and accuracy performance on this task. It is unknown whether strategy instruction on the ROCF would also transfer to performance improvement on copying and the recall of another complex figure. Participants were 98 typically developing children (aged 9.5-12.6 years, M = 10.6). Children completed the ROCF (copy and recall) as a pretest. Approximately a month later, they were randomized to complete the ROCF with strategy instruction in the form of a stepwise administration of the ROCF or again in the standard format. All children then copied and recalled the Modified Taylor Complex Figure (MTCF). All productions were assessed in terms of organization, accuracy and completion time. Organization scores for the MTCF did not differ for the two groups for the copy production, but did differ for the recall production, indicating transfer. Accuracy and completion times did not differ between groups. Performance on all measures, except copy accuracy, improved between pretest ROCF and posttest MTCF production for both groups, suggesting practice effects. Findings indicate that transfer of strategy instruction from one complex figure to another is only present for organization of recalled information. The increase in RCF-OSS scores did not lead to a higher accuracy or a faster copy or recall.

An evaluation of the performance of two binaural beamformers in complex and dynamic multitalker environments.

Science.gov (United States)

Best, Virginia; Mejia, Jorge; Freeston, Katrina; van Hoesel, Richard J; Dillon, Harvey

2015-01-01

Binaural beamformers are super-directional hearing aids created by combining microphone outputs from each side of the head. While they offer substantial improvements in SNR over conventional directional hearing aids, the benefits (and possible limitations) of these devices in realistic, complex listening situations have not yet been fully explored. In this study we evaluated the performance of two experimental binaural beamformers. Testing was carried out using a horizontal loudspeaker array. Background noise was created using recorded conversations. Performance measures included speech intelligibility, localization in noise, acceptable noise level, subjective ratings, and a novel dynamic speech intelligibility measure. Participants were 27 listeners with bilateral hearing loss, fitted with BTE prototypes that could be switched between conventional directional or binaural beamformer microphone modes. Relative to the conventional directional microphones, both binaural beamformer modes were generally superior for tasks involving fixed frontal targets, but not always for situations involving dynamic target locations. Binaural beamformers show promise for enhancing listening in complex situations when the location of the source of interest is predictable.

Probabilistic performance assessment of complex energy process systems - The case of a self-sustained sanitation system.

Science.gov (United States)

Kolios, Athanasios; Jiang, Ying; Somorin, Tosin; Sowale, Ayodeji; Anastasopoulou, Aikaterini; Anthony, Edward J; Fidalgo, Beatriz; Parker, Alison; McAdam, Ewan; Williams, Leon; Collins, Matt; Tyrrel, Sean

2018-05-01

A probabilistic modelling approach was developed and applied to investigate the energy and environmental performance of an innovative sanitation system, the "Nano-membrane Toilet" (NMT). The system treats human excreta via an advanced energy and water recovery island with the aim of addressing current and future sanitation demands. Due to the complex design and inherent characteristics of the system's input material, there are a number of stochastic variables which may significantly affect the system's performance. The non-intrusive probabilistic approach adopted in this study combines a finite number of deterministic thermodynamic process simulations with an artificial neural network (ANN) approximation model and Monte Carlo simulations (MCS) to assess the effect of system uncertainties on the predicted performance of the NMT system. The joint probability distributions of the process performance indicators suggest a Stirling Engine (SE) power output in the range of 61.5-73 W with a high confidence interval (CI) of 95%. In addition, there is high probability (with 95% CI) that the NMT system can achieve positive net power output between 15.8 and 35 W. A sensitivity study reveals the system power performance is mostly affected by SE heater temperature. Investigation into the environmental performance of the NMT design, including water recovery and CO 2 /NO x emissions, suggests significant environmental benefits compared to conventional systems. Results of the probabilistic analysis can better inform future improvements on the system design and operational strategy and this probabilistic assessment framework can also be applied to similar complex engineering systems.

Impact of Business Interoperability on the Performance of Complex Cooperative Supply Chain Networks: A Case Study

Directory of Open Access Journals (Sweden)

Izunildo Cabral

2018-01-01

Full Text Available This paper proposes an agent-based model for evaluating the effect of business interoperability on the performance of cooperative supply chain networks. The model is based on insights from the Industrial Marketing and Purchasing network approach and the complex systems theory perspective. To demonstrate its applicability, an explanatory case study regarding a Portuguese reverse logistics cooperative supply chain network is presented. Face-to-face interviews and forms were used to collect data. The findings show that the establishment of appropriate levels of business interoperability has helped to reduce several non-value-added interaction processes and consequently improve the operational performance of the Valorpneu network. Regarding the research implications, this paper extends the current knowledge on business interoperability and an important problem in business: how business interoperability gaps in dyadic organizational relationships affect the network of companies that the two companies belong to—network effect. In terms of practical implications, managers can use the proposed model as a starting point to simulate complex interactions between supply chain network partners and understand better how the performance of their networks emerges from these interactions and from the adoption of different levels of business interoperability.

On improving the performance of nonphotochemical quenching in CP29 light-harvesting antenna complex

Energy Technology Data Exchange (ETDEWEB)

Berman, Gennady P. [Theoretical Division, T-4, Los Alamos National Laboratory, and the New Mexico Consortium, Los Alamos, NM 87544 (United States); Nesterov, Alexander I., E-mail: nesterov@cencar.udg.mx [Departamento de Física, CUCEI, Universidad de Guadalajara, Av. Revolución 1500, Guadalajara, CP 44420, Jalisco (Mexico); Sayre, Richard T. [Biological Division, B-11, Los Alamos National Laboratory, and the New Mexico Consortium, Los Alamos, NM 87544 (United States); Still, Susanne [Department of Information and Computer Sciences, and Department of Physics and Astronomy, University of Hawaii at Mānoa, 1860 East–West Road, Honolulu, HI 96822 (United States)

2016-03-22

We model and simulate the performance of charge-transfer in nonphotochemical quenching (NPQ) in the CP29 light-harvesting antenna-complex associated with photosystem II (PSII). The model consists of five discrete excitonic energy states and two sinks, responsible for the potentially damaging processes and charge-transfer channels, respectively. We demonstrate that by varying (i) the parameters of the chlorophyll-based dimer, (ii) the resonant properties of the protein-solvent environment interaction, and (iii) the energy transfer rates to the sinks, one can significantly improve the performance of the NPQ. Our analysis suggests strategies for improving the performance of the NPQ in response to environmental changes, and may stimulate experimental verification. - Highlights: • Improvement of the efficiency of the charge-transfer nonphotochemical quenching in CP29. • Strategy for restoring the NPQ efficiency when the environment changes. • By changing of energy transfer rates to the sinks, one can significantly improve the performance of the NPQ.

Childhood school performance, education and occupational complexity: a life-course study of dementia in the Kungsholmen Project.

Science.gov (United States)

Dekhtyar, Serhiy; Wang, Hui-Xin; Fratiglioni, Laura; Herlitz, Agneta

2016-08-01

Cognitive reserve hypothesis predicts that intellectually demanding activities over the life course protect against dementia. We investigate if childhood school performance remains associated with dementia once education and occupational complexity are taken into account. A cohort of 440 individuals aged 75+ from the Kungsholmen Project was followed up for 9 years to detect dementia. To measure early-life contributors to reserve, we used grades at age 9-10 extracted from the school archives. Data on formal education and occupational complexity were collected at baseline and first follow-up. Dementia was ascertained through comprehensive clinical examination. Cox models estimated the relationship between life-course cognitive reserve measures and dementia. Dementia risk was elevated [hazard ratio (HR): 1.54, 95% confidence interval (CI): 1.03 to 2.29] in individuals with low early-life school grades after adjustment for formal educational attainment and occupational complexity. Secondary education was associated with a lower risk of dementia (HR: 0.72, 95% CI: 0.50 to 1.03), although the effects of post-secondary and university degrees were indistinguishable from baseline. Occupational complexity with data and things was not related to dementia. However, an association was found between high occupational complexity with people and dementia, albeit only in women (HR: 0.39, 95% CI: 0.14 to 0.99). The pattern of results remained unchanged after adjustment for genetic susceptibility, comorbidities and depressive symptoms. Low early-life school performance is associated with an elevated risk of dementia, independent of subsequent educational and occupational attainment. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Mitigation of Corrosion in 5 Series Al-Mg Alloys in Marine Environments: Grain Boundary Engineering and Cold Spray Coating Approaches

Science.gov (United States)

2014-03-26

34 thick walls was custom fabricated and bolted to six 5/8" threaded rod studs epoxied into the floor of the lab. Upon installation of the robot, a...mm while performing pre-programmed movements/operations. The robot required a stand that bolted to the floor to ensure the robot would not move or tip

The Effects of Enzyme Complex on Performance, Intestinal Health and Nutrient Digestibility of Weaned Pigs

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J. Q. Yi

2013-08-01

Full Text Available Two experiments were conducted to evaluate the effect of supplementing a corn-soybean meal-based diet with an enzyme complex containing amylase, protease and xylanase on the performance, intestinal health, apparent ileal digestibility of amino acids and nutrient digestibility of weaned pigs. In Exp. 1, 108 piglets weaned at 28 d of age were fed one of three diets containing 0 (control, 100, or 150 ppm enzyme complex for 4 wks, based on a two-phase feeding program namely 1 to 7 d (phase 1 and 8 to 28 d (phase 2. At the end of the experiment, six pigs from the control group and the group supplemented with 150 ppm enzyme complex were chosen to collect digesta samples from intestine to measure viscosity and pH in the stomach, ileum, and cecum, as well as volatile fatty acid concentrations and composition of the microflora in the cecum and colon. There were linear increases (p<0.01 in weight gain, gain: feed ratio and digestibility of gross energy with the increasing dose rate of enzyme supplementation during the whole experiment. Supplementation with enzyme complex increased the digesta viscosity in the stomach (p<0.05 and significantly increased (p<0.01 the concentrations of acetic, propionic and butyric acid in the cecum and colon. Enzyme supplementation also significantly increased the population of Lactobacilli (p<0.01 in the cecum and decreased the population of E. coli (p<0.05 in the colon. In Exp. 2, six crossbred barrows (initial body weight: 18.26±1.21 kg, fitted with a simple T-cannula at the distal ileum, were assigned to three dietary treatments according to a replicated 3×3 Latin Square design. The experimental diets were the same as the diets used in phase 2 in Exp. 1. Apparent ileal digestibility of isoleucine (p<0.01, valine (p<0.05 and aspartic acid (p<0.05 linearly increased with the increasing dose rate of enzyme supplementation. In conclusion, supplementation of the diet with an enzyme complex containing amylase, protease and

Self-Efficacy, Task Complexity and Task Performance: Exploring Interactions in Two Versions of Vocabulary Learning Tasks

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Wu, Xiaoli; Lowyck, Joost; Sercu, Lies; Elen, Jan

2012-01-01

The present study aimed for better understanding of the interactions between task complexity and students' self-efficacy beliefs and students' use of learning strategies, and finally their interacting effects on task performance. This investigation was carried out in the context of Chinese students learning English as a foreign language in a…

Effects of task complexity on rhythmic reproduction performance in adults.

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Iannarilli, Flora; Vannozzi, Giuseppe; Iosa, Marco; Pesce, Caterina; Capranica, Laura

2013-02-01

The aim of the present study was to investigate the effect of task complexity on the capability to reproduce rhythmic patterns. Sedentary musically illiterate individuals (age: 34.8±4.2 yrs; M±SD) were administered a rhythmic test including three rhythmic patterns to be reproduced by means of finger-tapping, foot-tapping and walking. For the quantification of subjects' ability in the reproduction of rhythmic patterns, qualitative and quantitative parameters were submitted to analysis. A stereophotogrammetric system was used to reconstruct and evaluate individual performances. The findings indicated a good internal stability of the rhythmic reproduction, suggesting that the present experimental design is suitable to discriminate the participants' rhythmic ability. Qualitative aspects of rhythmic reproduction (i.e., speed of execution and temporal ratios between events) varied as a function of the perceptual-motor requirements of the rhythmic reproduction task, with larger reproduction deviations in the walking task. Copyright © 2013 Elsevier B.V. All rights reserved.

A Human-Robot Co-Manipulation Approach Based on Human Sensorimotor Information.

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Peternel, Luka; Tsagarakis, Nikos; Ajoudani, Arash

2017-07-01

This paper aims to improve the interaction and coordination between the human and the robot in cooperative execution of complex, powerful, and dynamic tasks. We propose a novel approach that integrates online information about the human motor function and manipulability properties into the hybrid controller of the assistive robot. Through this human-in-the-loop framework, the robot can adapt to the human motor behavior and provide the appropriate assistive response in different phases of the cooperative task. We experimentally evaluate the proposed approach in two human-robot co-manipulation tasks that require specific complementary behavior from the two agents. Results suggest that the proposed technique, which relies on a minimum degree of task-level pre-programming, can achieve an enhanced physical human-robot interaction performance and deliver appropriate level of assistance to the human operator.

Effects of long-term practice and task complexity on brain activities when performing abacus-based mental calculations: a PET study

International Nuclear Information System (INIS)

Wu, Tung-Hsin; Chen, Chia-Lin; Huang, Yung-Hui; Liu, Ren-Shyan; Hsieh, Jen-Chuen; Lee, Jason J.S.

2009-01-01

The aim of this study was to examine the neural bases for the exceptional mental calculation ability possessed by Chinese abacus experts through PET imaging. We compared the different regional cerebral blood flow (rCBF) patterns using 15 O-water PET in 10 abacus experts and 12 non-experts while they were performing each of the following three tasks: covert reading, simple addition, and complex contiguous addition. All data collected were analyzed using SPM2 and MNI templates. For non-experts during the tasks of simple addition, the observed activation of brain regions were associated with coordination of language (inferior frontal network) and visuospatial processing (left parietal/frontal network). Similar activation patterns but with a larger visuospatial processing involvement were observed during complex contiguous addition tasks, suggesting the recruitment of more visuospatial memory for solving the complex problems. For abacus experts, however, the brain activation patterns showed slight differences when they were performing simple and complex addition tasks, both of which involve visuospatial processing (bilateral parietal/frontal network). These findings supported the notion that the experts were completing all the calculation process on a virtual mental abacus and relying on this same computational strategy in both simple and complex tasks, which required almost no increasing brain workload for solving the latter. In conclusion, after intensive training and practice, the neural pathways in an abacus expert have been connected more effectively for performing the number encoding and retrieval that are required in abacus tasks, resulting in exceptional mental computational ability. (orig.)

The cognitive complexity of concurrent cognitive-motor tasks reveals age-related deficits in motor performance

DEFF Research Database (Denmark)

Oliveira, Anderson Souza; Reiche, Mikkel Staall; Vinescu, Cristina Ioana

2018-01-01

Aging reduces cognitive functions, and such impairments have implications in mental and motor performance. Cognitive function has been recently linked to the risk of falls in older adults. Physical activities have been used to attenuate the declines in cognitive functions and reduce fall incidence......, but little is known whether a physically active lifestyle can maintain physical performance under cognitively demanding conditions. The aim of this study was to verify whether physically active older adults present similar performance deficits during upper limb response time and precision stepping walking...... tasks when compared to younger adults. Both upper limb and walking tasks involved simple and complex cognitive demands through decision-making. For both tasks, decision-making was assessed by including a distracting factor to the execution. The results showed that older adults were substantially slower...

Effect of micro lesions of the basal ganglia on ballistic movements in patients with deep brain stimulation.

Science.gov (United States)

Singh, Arun; Mehrkens, Jan H; Bötzel, Kai

2012-03-15

Bradykinesia and hypokinesia are the prominent symptoms of substantia nigra degeneration in Parkinson's disease (PD). In segmental dystonia, movements of not affected limbs are not impaired. Here we studied the impact of the mere implantation of stimulation electrodes on the performance of fast movements in these two groups. We investigated 9 PD patients with subthalamic electrodes and 9 patients with segmental dystonia with electrodes in the globus pallidus internum. Patients were studied on the first postoperative day without electrical stimulation of the electrodes. Subjects had to perform boxing movements with either touching the target or stopping the fist in front of the target. PD subjects performed significantly faster movements in the touch-task only as compared to dystonic patients. No difference was seen in the stopping task. In conclusion, our findings suggest that a small subthalamic lesion in individuals with PD specifically reverses bradykinesia during simple ballistic movements (touch) but not during complex ones requiring more pre-programming (no-touch paradigm). Copyright © 2011 Elsevier B.V. All rights reserved.

The Effect of Focus on Form and Task Complexity on L2 Learners' Oral Task Performance

Science.gov (United States)

Salimi, Asghar

2015-01-01

Second Language learners' oral task performance has been one of interesting and research generating areas of investigations in the field of second language acquisition specially, task-based language teaching and learning. The main purpose of the present study is to investigate the effect of focus on form and task complexity on L2 learners' oral…

High-performance mussel-inspired adhesives of reduced complexity.

Science.gov (United States)

Ahn, B Kollbe; Das, Saurabh; Linstadt, Roscoe; Kaufman, Yair; Martinez-Rodriguez, Nadine R; Mirshafian, Razieh; Kesselman, Ellina; Talmon, Yeshayahu; Lipshutz, Bruce H; Israelachvili, Jacob N; Waite, J Herbert

2015-10-19

Despite the recent progress in and demand for wet adhesives, practical underwater adhesion remains limited or non-existent for diverse applications. Translation of mussel-inspired wet adhesion typically entails catechol functionalization of polymers and/or polyelectrolytes, and solution processing of many complex components and steps that require optimization and stabilization. Here we reduced the complexity of a wet adhesive primer to synthetic low-molecular-weight catecholic zwitterionic surfactants that show very strong adhesion (∼50 mJ m(-2)) and retain the ability to coacervate. This catecholic zwitterion adheres to diverse surfaces and self-assembles into a molecularly smooth, thin (adhesive for nanofabrication. This study significantly simplifies bio-inspired themes for wet adhesion by combining catechol with hydrophobic and electrostatic functional groups in a small molecule.

The role of human performance in safe operation of complex plants

International Nuclear Information System (INIS)

Preda, Irina Aida; Lazar, Roxana Elena; Croitoru, Cornelia

1999-01-01

According to statistics, about 20-30% from the failures occurring in plants are caused directly or indirectly by human errors. Furthermore, it was established that 10-15 percents of the global failures are related to the human errors. These are mainly due to the wrong actions, maintenance errors, and misinterpretation of instruments. The human performance is influenced by: professional ability, complexity and danger of the plant, experience in the same working place, level of skills, events in personal and/or professional life, discipline, social ambience and somatic health. The human performances assessment in the probabilistic safety assessment offers the possibility of evaluation for human contribution to the events sequences outcome. A human error may be recovered before the unwanted consequences had been occurred on system. This paper presents the possibilities to use the probabilistic methods (event tree, fault tree) to identify the solution for human reliability improvement in order to minimise the risk in industrial plant operation. Also, are defined the human error types and their causes and the 'decision tree method' is presented as technique in our analyses for human reliability assessment. The exemplification of human error analysis method was achieved based on operation data for Valcea heavy water pilot plant. (authors)

Performance-oriented Architecture and the Spatial and Material Organisation Complex. Rethinking the Definition, Role and Performative Capacity of the Spatial and Material Boundaries of the Built Environment

Directory of Open Access Journals (Sweden)

Michael Ulrich Hensel

2011-03-01

Full Text Available This article is based on the proposition that performance-oriented design is characterised by four domains of ‘active agency’: the human subject, the spatial and material organisation complex and the environment (Hensel, 2010. While these four domains are seen to be interdependent and interacting with one another, it is nevertheless necessary to examine each in its own right. However, the spatial and material organisation complex contains both the spatial and material domains, which are interdependent to such a degree that these need to be examined in relation to one another and also in relation to the specific environment they are set within and interacting with. To explore this combined domain within the context of performance-oriented design is the aim of this article, in particularly in relation to the question of the definition and performative capacity of spatial and material boundaries. The various sections are accompanied by research by design efforts undertaken in specified academic contexts, which are intended as examples of modes and areas of inquiry relative to the purpose of this article.

Impact of Cognitive Abilities and Prior Knowledge on Complex Problem Solving Performance – Empirical Results and a Plea for Ecologically Valid Microworlds

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Heinz-Martin Süß

2018-05-01

Full Text Available The original aim of complex problem solving (CPS research was to bring the cognitive demands of complex real-life problems into the lab in order to investigate problem solving behavior and performance under controlled conditions. Up until now, the validity of psychometric intelligence constructs has been scrutinized with regard to its importance for CPS performance. At the same time, different CPS measurement approaches competing for the title of the best way to assess CPS have been developed. In the first part of the paper, we investigate the predictability of CPS performance on the basis of the Berlin Intelligence Structure Model and Cattell’s investment theory as well as an elaborated knowledge taxonomy. In the first study, 137 students managed a simulated shirt factory (Tailorshop; i.e., a complex real life-oriented system twice, while in the second study, 152 students completed a forestry scenario (FSYS; i.e., a complex artificial world system. The results indicate that reasoning – specifically numerical reasoning (Studies 1 and 2 and figural reasoning (Study 2 – are the only relevant predictors among the intelligence constructs. We discuss the results with reference to the Brunswik symmetry principle. Path models suggest that reasoning and prior knowledge influence problem solving performance in the Tailorshop scenario mainly indirectly. In addition, different types of system-specific knowledge independently contribute to predicting CPS performance. The results of Study 2 indicate that working memory capacity, assessed as an additional predictor, has no incremental validity beyond reasoning. We conclude that (1 cognitive abilities and prior knowledge are substantial predictors of CPS performance, and (2 in contrast to former and recent interpretations, there is insufficient evidence to consider CPS a unique ability construct. In the second part of the paper, we discuss our results in light of recent CPS research, which predominantly

Impact of Cognitive Abilities and Prior Knowledge on Complex Problem Solving Performance – Empirical Results and a Plea for Ecologically Valid Microworlds

Science.gov (United States)

Süß, Heinz-Martin; Kretzschmar, André

2018-01-01

The original aim of complex problem solving (CPS) research was to bring the cognitive demands of complex real-life problems into the lab in order to investigate problem solving behavior and performance under controlled conditions. Up until now, the validity of psychometric intelligence constructs has been scrutinized with regard to its importance for CPS performance. At the same time, different CPS measurement approaches competing for the title of the best way to assess CPS have been developed. In the first part of the paper, we investigate the predictability of CPS performance on the basis of the Berlin Intelligence Structure Model and Cattell’s investment theory as well as an elaborated knowledge taxonomy. In the first study, 137 students managed a simulated shirt factory (Tailorshop; i.e., a complex real life-oriented system) twice, while in the second study, 152 students completed a forestry scenario (FSYS; i.e., a complex artificial world system). The results indicate that reasoning – specifically numerical reasoning (Studies 1 and 2) and figural reasoning (Study 2) – are the only relevant predictors among the intelligence constructs. We discuss the results with reference to the Brunswik symmetry principle. Path models suggest that reasoning and prior knowledge influence problem solving performance in the Tailorshop scenario mainly indirectly. In addition, different types of system-specific knowledge independently contribute to predicting CPS performance. The results of Study 2 indicate that working memory capacity, assessed as an additional predictor, has no incremental validity beyond reasoning. We conclude that (1) cognitive abilities and prior knowledge are substantial predictors of CPS performance, and (2) in contrast to former and recent interpretations, there is insufficient evidence to consider CPS a unique ability construct. In the second part of the paper, we discuss our results in light of recent CPS research, which predominantly utilizes the

Stop: a fast procedure for the exact computation of the performance of complex probabilistic systems

International Nuclear Information System (INIS)

Corynen, G.C.

1982-01-01

A new set-theoretic method for the exact and efficient computation of the probabilistic performance of complex systems has been developed. The core of the method is a fast algorithm for disjointing a collection of product sets which is intended for systems with more than 1000 components and 100,000 cut sets. The method is based on a divide-and-conquer approach, in which a multidimensional problem is progressively decomposed into lower-dimensional subproblems along its dimensions. The method also uses a particular pointer system that eliminates the need to store the subproblems by only requiring the storage of pointers to those problems. Examples of the algorithm and the divide-and-conquer strategy are provided, and comparisons with other significant methods are made. Statistical complexity studies show that the expected time and space complexity of other methods is O(me/sup n/), but that our method is O(nm 3 log(m)). Problems which would require days of Cray-1 computer time with present methods can now be solved in seconds. Large-scale systems that can only be approximated with other techniques can now also be evaluated exactly

Complexities in innovation management in companies from the European industry. A path model of innovation project performance determinants

NARCIS (Netherlands)

Tepic, M.; Kemp, R.G.M.; Omta, S.W.F.; Fortuin, F.T.J.M.

2013-01-01

Purpose – The purpose of this paper is to provide an integrated framework of complex relations among innovation characteristics, organizational capabilities, innovation potential and innovation performance. Design/methodology/approach – The model is tested using partial least squares (PLS) modeling

Comparison of surface extraction techniques performance in computed tomography for 3D complex micro-geometry dimensional measurements

DEFF Research Database (Denmark)

Torralba, Marta; Jiménez, Roberto; Yagüe-Fabra, José A.

2018-01-01

micro-geometries as well (i.e., in the sub-mm dimensional range). However, there are different factors that may influence the CT process performance, being one of them the surface extraction technique used. In this paper, two different extraction techniques are applied to measure a complex miniaturized......The number of industrial applications of computed tomography (CT) for dimensional metrology in 100–103 mm range has been continuously increasing, especially in the last years. Due to its specific characteristics, CT has the potential to be employed as a viable solution for measuring 3D complex...... dental file by CT in order to analyze its contribution to the final measurement uncertainty in complex geometries at the mm to sub-mm scales. The first method is based on a similarity analysis: the threshold determination; while the second one is based on a gradient or discontinuity analysis: the 3D...

Product Complexity Impact on Quality and Delivery Performance

DEFF Research Database (Denmark)

Nielsen, Jeppe Bjerrum; Hvam, Lars

2011-01-01

Existing literature on product portfolio complexity is mainly focused on cost related aspects. It is widely acknowledged that an increase in a company’s product portfolio will lead to an increase in complexity related costs such as order management, procurement and inventory. The objective...... is increased, but it is not the only factor affected. We can document that there is a tendency towards increasing lead times as well as a drop in on time delivery and quality for newly introduced product variants. This means that the company experiences a reduced ability to deliver on time while also receiving...... of this article is to examine which other factors that might be affected when a company is expanding its product portfolio, if initiatives are not taken to accommodate this increase. Empirical work carried out in a large international engineering company having a market leader position confirms that cost...

Complexity Control of Fast Motion Estimation in H.264/MPEG-4 AVC with Rate-Distortion-Complexity optimization

DEFF Research Database (Denmark)

Wu, Mo; Forchhammer, Søren; Aghito, Shankar Manuel

2007-01-01

A complexity control algorithm for H.264 advanced video coding is proposed. The algorithm can control the complexity of integer inter motion estimation for a given target complexity. The Rate-Distortion-Complexity performance is improved by a complexity prediction model, simple analysis of the pa...... statistics and a control scheme. The algorithm also works well for scene change condition. Test results for coding interlaced video (720x576 PAL) are reported.......A complexity control algorithm for H.264 advanced video coding is proposed. The algorithm can control the complexity of integer inter motion estimation for a given target complexity. The Rate-Distortion-Complexity performance is improved by a complexity prediction model, simple analysis of the past...

Subjective task complexity in the control room

International Nuclear Information System (INIS)

Braarud, Per Oeivind

2000-05-01

Understanding of what makes a control room situation difficult to handle is important when studying operator performance, both with respect to prediction as well as improvement of the human performance. Previous exploratory work on complexity showed a potential for prediction and explanation of operator performance. This report investigates in further detail the theoretical background and the structure of operator rated task complexity. The report complements the previous work on complexity to make a basis for development of operator performance analysis tools. The first part of the report outlines an approach for studying the complexity of the control room crew's work. The approach draws upon man-machine research as well as problem solving research. The approach identifies five complexity-shaping components: 'task work characteristics', 'teamwork characteristics', 'individual skill', 'teamwork skill', and 'interface and support systems'. The crew's work complexity is related to concepts of human performance quality and human error. The second part of the report is a post-hoc exploratory analysis of four empirical HRP studies, where operators' conception of the complexity of control room work is assessed by questionnaires. The analysis deals with the structure of complexity questionnaire ratings, and the relationship between complexity ratings and human performance measures. The main findings from the analysis of structure was the identification of three task work factors which were named Masking, Information load and Temporal demand, and in addition the identification of one interface factor which was named Navigation. Post-hoc analysis suggests that operator's subjective complexity, which was assessed by questionnaires, is related to workload, task and system performance, and operator's self-rated performance. (Author). 28 refs., 47 tabs

COMPLEX TRAINING: A BRIEF REVIEW

Directory of Open Access Journals (Sweden)

William P. Ebben

2002-06-01

Full Text Available The effectiveness of plyometric training is well supported by research. Complex training has gained popularity as a training strategy combining weight training and plyometric training. Anecdotal reports recommend training in this fashion in order to improve muscular power and athletic performance. Recently, several studies have examined complex training. Despite the fact that questions remain about the potential effectiveness and implementation of this type of training, results of recent studies are useful in guiding practitioners in the development and implementation of complex training programs. In some cases, research suggests that complex training has an acute ergogenic effect on upper body power and the results of acute and chronic complex training include improved jumping performance. Improved performance may require three to four minutes rest between the weight training and plyometrics sets and the use of heavy weight training loads

Multi-scalar agent-based complex design systems - the case of CECO (Climatic -Ecologies) Studio; informed generative design systems and performance-driven design workflows

NARCIS (Netherlands)

Mostafavi, S.; Yu, S.; Biloria, N.M.

2014-01-01

This paper illustrates the application of different types of complex systems for digital form finding and design decision making with underlying methodological and pedagogical aims to emphasize performance-driven design solutions via combining generative methods of complex systems with simulation

Risk Management Capability Maturity and Performance of Complex Product and System (CoPS Projects with an Asian Perspective

Directory of Open Access Journals (Sweden)

Ren, Y.

2014-07-01

Full Text Available Complex Products and Systems (CoPS are high value, technology and engineering-intensive capital goods. The motivation of this study is the persistent high failure rate of CoPS projects, Asian CoPS provider’s weak capability and lack of specific research on CoPS risk management. This paper evaluates risk management maturity level of CoPS projects against a general CoPS risk management capability maturity model (RM-CMM developed by the authors. An Asian based survey was conducted to investigate the value of RM to project performance, and Asian (non-Japanese CoPS implementers’ perceived application of RM practices, their strengths and weaknesses. The survey result shows that higher RM maturity level leads to higher CoPS project performance. It also shows project complexity and uncertainty moderates the relationship between some RM practices and project performance, which implies that a contingency approach should be adopted to manage CoPS risks effectively. In addition, it shows that Asian CoPS implementers are weak in RM process and there are also rooms for improvement in the softer aspects of organizational capabilities and robustness.

Good distractions: Testing the effects of listening to an audiobook on driving performance in simple and complex road environments.

Science.gov (United States)

Nowosielski, Robert J; Trick, Lana M; Toxopeus, Ryan

2018-02-01

Distracted driving (driving while performing a secondary task) causes many collisions. Most research on distracted driving has focused on operating a cell-phone, but distracted driving can include eating while driving, conversing with passengers or listening to music or audiobooks. Although the research has focused on the deleterious effects of distraction, there may be situations where distraction improves driving performance. Fatigue and boredom are also associated with collision risk and it is possible that secondary tasks can help alleviate the effects of fatigue and boredom. Furthermore, it has been found that individuals with high levels of executive functioning as measured by the OSPAN (Operation Span) task show better driving while multitasking. In this study, licensed drivers were tested in a driving simulator (a car body surrounded by screens) that simulated simple or complex roads. Road complexity was manipulated by increasing traffic, scenery, and the number of curves in the drive. Participants either drove, or drove while listening to an audiobook. Driving performance was measured in terms of braking response time to hazards (HRT): the time required to brake in response to pedestrians or vehicles that suddenly emerged from the periphery into the path of the vehicle, speed, standard deviation of speed, standard deviation of lateral position (SDLP). Overall, braking times to hazards were higher on the complex drive than the simple one, though the effects of secondary tasks such as audiobooks were especially deleterious on the complex drive. In contrast, on the simple drive, driving while listening to an audiobook lead to faster HRT. We found evidence that individuals with high OSPAN scores had faster HRTs when listening to an audiobook. These results suggest that there are environmental and individual factors behind difference in the allocation of attention while listening to audiobooks while driving. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using iMCFA to Perform the CFA, Multilevel CFA, and Maximum Model for Analyzing Complex Survey Data.

Science.gov (United States)

Wu, Jiun-Yu; Lee, Yuan-Hsuan; Lin, John J H

2018-01-01

To construct CFA, MCFA, and maximum MCFA with LISREL v.8 and below, we provide iMCFA (integrated Multilevel Confirmatory Analysis) to examine the potential multilevel factorial structure in the complex survey data. Modeling multilevel structure for complex survey data is complicated because building a multilevel model is not an infallible statistical strategy unless the hypothesized model is close to the real data structure. Methodologists have suggested using different modeling techniques to investigate potential multilevel structure of survey data. Using iMCFA, researchers can visually set the between- and within-level factorial structure to fit MCFA, CFA and/or MAX MCFA models for complex survey data. iMCFA can then yield between- and within-level variance-covariance matrices, calculate intraclass correlations, perform the analyses and generate the outputs for respective models. The summary of the analytical outputs from LISREL is gathered and tabulated for further model comparison and interpretation. iMCFA also provides LISREL syntax of different models for researchers' future use. An empirical and a simulated multilevel dataset with complex and simple structures in the within or between level was used to illustrate the usability and the effectiveness of the iMCFA procedure on analyzing complex survey data. The analytic results of iMCFA using Muthen's limited information estimator were compared with those of Mplus using Full Information Maximum Likelihood regarding the effectiveness of different estimation methods.

Pediatric Neurosurgical Outcomes Following a Neurosurgery Health System Intervention at Mulago National Referral Hospital in Uganda.

Science.gov (United States)

Fuller, Anthony T; Haglund, Michael M; Lim, Stephanie; Mukasa, John; Muhumuza, Michael; Kiryabwire, Joel; Ssenyonjo, Hussein; Smith, Emily R

2016-11-01

Pediatric neurosurgical cases have been identified as an important target for impacting health disparities in Uganda, with over 50% of the population being less than 15 years of age. The objective of the present study was to evaluate the effects of the Duke-Mulago collaboration on pediatric neurosurgical outcomes in Mulago National Referral Hospital. We performed retrospective analysis of all pediatric neurosurgical cases who presented at Mulago National Referral Hospital in Kampala, Uganda, to examine overall, preprogram (2005-2007), and postprogram (2008-2013) outcomes. We analyzed mortality, presurgical infections, postsurgical infections, length of stay, types of procedures, and significant predictors of mortality. Data on neurosurgical cases was collected from surgical logbooks, patient charts, and Mulago National Referral Hospital's yearly death registry. Of 820 pediatric neurosurgical cases, outcome data were complete for 374 children. Among children who died within 30 days of a surgical procedure, the largest group was less than a year old (45%). Postinitiation of the Duke-Mulago collaboration, we identified an overall increase in procedures, with the greatest increase in cases with complex diagnoses. Although children ages 6-18 years of age were 6.66 times more likely to die than their younger counterparts preprogram, age was no longer a predictive variable postprogram. When comparing pre- and postprogram outcomes, mortality among pediatric patients within 30 days after a neurosurgical procedure increased from 4.3% to 10.0%, mortality after 30 days increased slightly from 4.9% to 5.0%, presurgical infections decreased by 4.6%, and postsurgery infections decreased slightly by 0.7%. Our data show the provision of more complex neurological procedures does not necessitate improved outcomes. Rather, combining these higher-level procedures with essential pre- and postoperative care and continued efforts in health system strengthening for pediatric neurosurgical

The role of human performance in the safety complex plants' operation

International Nuclear Information System (INIS)

Preda, Irina Aida; Lazar, Roxana Elena; Croitoru, Cornelia

1999-01-01

According to statistics, about 20-30% from the failures occurred in the plants are caused directly or indirectly by human errors. Furthermore, it was established that 10-15% of the global failures are related with the human errors. These are mainly due to the wrong actions, maintenance errors, and misinterpretation of instruments. The human performance is influenced by: professional ability, complexity and danger to the plant experience in the working place, level of skills, events in personal and/or professional life, discipline, social ambience, somatic health. The human performances' assessment in the probabilistic safety assessment offers the possibility of evaluation of human contribution to the events sequences outcome. Not all the human errors have impact on the system. A human error may be recovered before the unwanted consequences had been occurred on system. This paper presents the possibilities to use the probabilistic method (event tree, fault tree) to identify the solutions for human reliability improved in order to minimize the risk in industrial plants' operation. Also, the human error types and their causes are defined and the 'decision tree method' as technique in our analysis for human reliability assessment is presented. The exemplification of human error analysis method was achieved based on operation data for Valcea Heavy Water Pilot Plant. As initiating event for the accident state 'the steam supply interruption' event has been considered. The human errors' contribution was analysed for the accident sequence with the worst consequences. (authors)

"One Task Fits All"? The Roles of Task Complexity, Modality, and Working Memory Capacity in L2 Performance

Science.gov (United States)

Zalbidea, Janire

2017-01-01

The present study explores the independent and interactive effects of task complexity and task modality on linguistic dimensions of second language (L2) performance and investigates how these effects are modulated by individual differences in working memory capacity. Thirty-two intermediate learners of L2 Spanish completed less and more complex…

Explaining high and low performers in complex intervention trials: a new model based on diffusion of innovations theory.

Science.gov (United States)

McMullen, Heather; Griffiths, Chris; Leber, Werner; Greenhalgh, Trisha

2015-05-31

Complex intervention trials may require health care organisations to implement new service models. In a recent cluster randomised controlled trial, some participating organisations achieved high recruitment, whereas others found it difficult to assimilate the intervention and were low recruiters. We sought to explain this variation and develop a model to inform organisational participation in future complex intervention trials. The trial included 40 general practices in a London borough with high HIV prevalence. The intervention was offering a rapid HIV test as part of the New Patient Health Check. The primary outcome was mean CD4 cell count at diagnosis. The process evaluation consisted of several hundred hours of ethnographic observation, 21 semi-structured interviews and analysis of routine documents (e.g., patient leaflets, clinical protocols) and trial documents (e.g., inclusion criteria, recruitment statistics). Qualitative data were analysed thematically using--and, where necessary, extending--Greenhalgh et al.'s model of diffusion of innovations. Narrative synthesis was used to prepare case studies of four practices representing maximum variety in clinicians' interest in HIV (assessed by level of serological testing prior to the trial) and performance in the trial (high vs. low recruiters). High-recruiting practices were, in general though not invariably, also innovative practices. They were characterised by strong leadership, good managerial relations, readiness for change, a culture of staff training and available staff time ('slack resources'). Their front-line staff believed that patients might benefit from the rapid HIV test ('relative advantage'), were emotionally comfortable administering it ('compatibility'), skilled in performing it ('task issues') and made creative adaptations to embed the test in local working practices ('reinvention'). Early experience of a positive HIV test ('observability') appeared to reinforce staff commitment to recruiting

Comparative Performance of Complex-Valued B-Spline and Polynomial Models Applied to Iterative Frequency-Domain Decision Feedback Equalization of Hammerstein Channels.

Science.gov (United States)

Chen, Sheng; Hong, Xia; Khalaf, Emad F; Alsaadi, Fuad E; Harris, Chris J

2017-12-01

Complex-valued (CV) B-spline neural network approach offers a highly effective means for identifying and inverting practical Hammerstein systems. Compared with its conventional CV polynomial-based counterpart, a CV B-spline neural network has superior performance in identifying and inverting CV Hammerstein systems, while imposing a similar complexity. This paper reviews the optimality of the CV B-spline neural network approach. Advantages of B-spline neural network approach as compared with the polynomial based modeling approach are extensively discussed, and the effectiveness of the CV neural network-based approach is demonstrated in a real-world application. More specifically, we evaluate the comparative performance of the CV B-spline and polynomial-based approaches for the nonlinear iterative frequency-domain decision feedback equalization (NIFDDFE) of single-carrier Hammerstein channels. Our results confirm the superior performance of the CV B-spline-based NIFDDFE over its CV polynomial-based counterpart.

Performance and Complexity Analysis of Blind FIR Channel Identification Algorithms Based on Deterministic Maximum Likelihood in SIMO Systems

DEFF Research Database (Denmark)

De Carvalho, Elisabeth; Omar, Samir; Slock, Dirk

2013-01-01

We analyze two algorithms that have been introduced previously for Deterministic Maximum Likelihood (DML) blind estimation of multiple FIR channels. The first one is a modification of the Iterative Quadratic ML (IQML) algorithm. IQML gives biased estimates of the channel and performs poorly at low...... to the initialization. Its asymptotic performance does not reach the DML performance though. The second strategy, called Pseudo-Quadratic ML (PQML), is naturally denoised. The denoising in PQML is furthermore more efficient than in DIQML: PQML yields the same asymptotic performance as DML, as opposed to DIQML......, but requires a consistent initialization. We furthermore compare DIQML and PQML to the strategy of alternating minimization w.r.t. symbols and channel for solving DML (AQML). An asymptotic performance analysis, a complexity evaluation and simulation results are also presented. The proposed DIQML and PQML...

A Simple and High Performing Rate Control Initialization Method for H.264 AVC Coding Based on Motion Vector Map and Spatial Complexity at Low Bitrate

Directory of Open Access Journals (Sweden)

Yalin Wu

2014-01-01

Full Text Available The temporal complexity of video sequences can be characterized by motion vector map which consists of motion vectors of each macroblock (MB. In order to obtain the optimal initial QP (quantization parameter for the various video sequences which have different spatial and temporal complexities, this paper proposes a simple and high performance initial QP determining method based on motion vector map and temporal complexity to decide an initial QP in given target bit rate. The proposed algorithm produces the reconstructed video sequences with outstanding and stable quality. For any video sequences, the initial QP can be easily determined from matrices by target bit rate and mapped spatial complexity using proposed mapping method. Experimental results show that the proposed algorithm can show more outstanding objective and subjective performance than other conventional determining methods.

Performance and complexity of tunable sparse network coding with gradual growing tuning functions over wireless networks

OpenAIRE

Garrido Ortiz, Pablo; Sørensen, Chres W.; Lucani Roetter, Daniel Enrique; Agüero Calvo, Ramón

2016-01-01

Random Linear Network Coding (RLNC) has been shown to be a technique with several benefits, in particular when applied over wireless mesh networks, since it provides robustness against packet losses. On the other hand, Tunable Sparse Network Coding (TSNC) is a promising concept, which leverages a trade-off between computational complexity and goodput. An optimal density tuning function has not been found yet, due to the lack of a closed-form expression that links density, performance and comp...

A study on the identification of cognitive complexity factors related to the complexity of procedural steps

Energy Technology Data Exchange (ETDEWEB)

Park, Jin Kyun; Jeong, Kwang Sup; Jung, Won Dea [KAERI, Taejon (Korea, Republic of)

2004-07-01

In complex systems, it is well recognized that the provision of understandable procedures that allow operators to clarify 'what needs to be done' and 'how to do it' is one of the requisites to confirm their safety. In this regard, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is evinced from the comparisons between SC scores and operators' performance data. To this end, the comparisons between operators' performance data with their behavior in conducting prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect operators' cognitive burden are identified. Although a well-designed experiment is indispensable in confirming the appropriateness of cognitive complexity factors, it is strongly believed that the change of an operator's performance can be more authentically explained if they are taken into consideration.

A study on the identification of cognitive complexity factors related to the complexity of procedural steps

International Nuclear Information System (INIS)

Park, Jin Kyun; Jeong, Kwang Sup; Jung, Won Dea

2004-01-01

In complex systems, it is well recognized that the provision of understandable procedures that allow operators to clarify 'what needs to be done' and 'how to do it' is one of the requisites to confirm their safety. In this regard, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is evinced from the comparisons between SC scores and operators' performance data. To this end, the comparisons between operators' performance data with their behavior in conducting prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect operators' cognitive burden are identified. Although a well-designed experiment is indispensable in confirming the appropriateness of cognitive complexity factors, it is strongly believed that the change of an operator's performance can be more authentically explained if they are taken into consideration

A simple behaviour provides accuracy and flexibility in odour plume tracking--the robotic control of sensory-motor coupling in silkmoths.

Science.gov (United States)

Ando, Noriyasu; Kanzaki, Ryohei

2015-12-01

Odour plume tracking is an essential behaviour for animal survival. A fundamental strategy for this is to move upstream and then across-stream. Male silkmoths, Bombyx mori, display this strategy as a pre-programmed sequential behaviour. They walk forward (surge) in response to the female sex pheromone and perform a zigzagging 'mating dance'. Though pre-programmed, the surge direction is modulated by bilateral olfactory input and optic flow. However, the nature of the interaction between these two sensory modalities and contribution of the resultant motor command to localizing an odour source are still unknown. We evaluated the ability of the silkmoth to localize an odour source under conditions of disturbed sensory-motor coupling, using a silkmoth-driven mobile robot. The significance of the bilateral olfaction of the moth was confirmed by inverting the olfactory input to the antennae, or its motor output. Inversion of the motor output induced consecutive circling, which was inhibited by covering the visual field of the moth. This suggests that the corollary discharge from the motor command and the reafference of self-generated optic flow generate compensatory signals to guide the surge accurately. Additionally, after inverting the olfactory input, the robot successfully tracked the odour plume by using a combination of behaviours. These results indicate that accurate guidance of the reflexive surge by integrating bilateral olfactory and visual information with innate pre-programmed behaviours increases the flexibility to track an odour plume even under disturbed circumstances. © 2015. Published by The Company of Biologists Ltd.

On Measuring the Complexity of Networks: Kolmogorov Complexity versus Entropy

Directory of Open Access Journals (Sweden)

Mikołaj Morzy

2017-01-01

Full Text Available One of the most popular methods of estimating the complexity of networks is to measure the entropy of network invariants, such as adjacency matrices or degree sequences. Unfortunately, entropy and all entropy-based information-theoretic measures have several vulnerabilities. These measures neither are independent of a particular representation of the network nor can capture the properties of the generative process, which produces the network. Instead, we advocate the use of the algorithmic entropy as the basis for complexity definition for networks. Algorithmic entropy (also known as Kolmogorov complexity or K-complexity for short evaluates the complexity of the description required for a lossless recreation of the network. This measure is not affected by a particular choice of network features and it does not depend on the method of network representation. We perform experiments on Shannon entropy and K-complexity for gradually evolving networks. The results of these experiments point to K-complexity as the more robust and reliable measure of network complexity. The original contribution of the paper includes the introduction of several new entropy-deceiving networks and the empirical comparison of entropy and K-complexity as fundamental quantities for constructing complexity measures for networks.

Improvement of a three-dimensional atmospheric dynamic model and examination of its performance over complex terrain

International Nuclear Information System (INIS)

Nagai, Haruyasu; Yamazawa, Hiromi

1994-11-01

A three-dimensional atmospheric dynamic model (PHYSIC) was improved and its performance was examined using the meteorological data observed at a coastal area with a complex terrain. To introduce synoptic meteorological conditions into the model, the initial and boundary conditions were improved. By this improvement, the model can predict the temporal change of wind field for more than 24 hours. Moreover, the model successfully simulates the land and sea breeze observed at Shimokita area in the summer of 1992. (author)

Low-Complexity Interference-Free Downlink Channel Assignment with Improved Performance in Coordinated Small Cells

KAUST Repository

Radaydeh, Redha M.

2015-05-01

This paper proposes a low-complexity interference-free channel assignment scheme with improved desired downlink performance in coordinated multi-antenna small-coverage access points (APs) that employ the open-access control strategy. The adopted system treats the case when each user can be granted an access to one of the available channels at a time. Moreover, each receive terminal can suppress a limited number of resolvable interfering sources via its highly-correlated receive array. On the other hand, the operation of the deployed APs can be coordinated to serve active users, and the availability of multiple physical channels and the use of uncorrelated transmit antennas at each AP are exploited to improve the performance of supported users. The analysis provides new approaches to use the transmit antenna array at each AP, the multiple physical channels, the receive antenna array at each user in order to identify interference-free channels per each user, and then to select a downlink channel that provides the best possible improved performance. The event of concurrent interference-free channel identification by different users is also treated to further improve the desired link associated with the scheduled user. The analysis considers the practical scenario of imperfect identification of interference-free channel by an active user and/or the imperfectness in scheduling concurrent users requests on the same channel. The developed formulations can be used to study any performance metric and they are applicable for any statistical and geometric channel models. © 2015 IEEE.

Estimating the operator's performance time of emergency procedural tasks based on a task complexity measure

International Nuclear Information System (INIS)

Jung, Won Dae; Park, Jink Yun

2012-01-01

It is important to understand the amount of time required to execute an emergency procedural task in a high-stress situation for managing human performance under emergencies in a nuclear power plant. However, the time to execute an emergency procedural task is highly dependent upon expert judgment due to the lack of actual data. This paper proposes an analytical method to estimate the operator's performance time (OPT) of a procedural task, which is based on a measure of the task complexity (TACOM). The proposed method for estimating an OPT is an equation that uses the TACOM as a variable, and the OPT of a procedural task can be calculated if its relevant TACOM score is available. The validity of the proposed equation is demonstrated by comparing the estimated OPTs with the observed OPTs for emergency procedural tasks in a steam generator tube rupture scenario.

A high performance, low power computational platform for complex sensing operations in smart cities

KAUST Repository

Jiang, Jiming; Claudel, Christian

2017-01-01

This paper presents a new wireless platform designed for an integrated traffic/flash flood monitoring system. The sensor platform is built around a 32-bit ARM Cortex M4 microcontroller and a 2.4GHz 802.15.4802.15.4 ISM compliant radio module. It can be interfaced with fixed traffic sensors, or receive data from vehicle transponders. This platform is specifically designed for solar-powered, low bandwidth, high computational performance wireless sensor network applications. A self-recovering unit is designed to increase reliability and allow periodic hard resets, an essential requirement for sensor networks. A radio monitoring circuitry is proposed to monitor incoming and outgoing transmissions, simplifying software debugging. We illustrate the performance of this wireless sensor platform on complex problems arising in smart cities, such as traffic flow monitoring, machine-learning-based flash flood monitoring or Kalman-filter based vehicle trajectory estimation. All design files have been uploaded and shared in an open science framework, and can be accessed from [1]. The hardware design is under CERN Open Hardware License v1.2.

A high performance, low power computational platform for complex sensing operations in smart cities

KAUST Repository

Jiang, Jiming

2017-02-02

This paper presents a new wireless platform designed for an integrated traffic/flash flood monitoring system. The sensor platform is built around a 32-bit ARM Cortex M4 microcontroller and a 2.4GHz 802.15.4802.15.4 ISM compliant radio module. It can be interfaced with fixed traffic sensors, or receive data from vehicle transponders. This platform is specifically designed for solar-powered, low bandwidth, high computational performance wireless sensor network applications. A self-recovering unit is designed to increase reliability and allow periodic hard resets, an essential requirement for sensor networks. A radio monitoring circuitry is proposed to monitor incoming and outgoing transmissions, simplifying software debugging. We illustrate the performance of this wireless sensor platform on complex problems arising in smart cities, such as traffic flow monitoring, machine-learning-based flash flood monitoring or Kalman-filter based vehicle trajectory estimation. All design files have been uploaded and shared in an open science framework, and can be accessed from [1]. The hardware design is under CERN Open Hardware License v1.2.

Performance of predictive models in phase equilibria of complex associating systems: PC-SAFT and CEOS/GE

Directory of Open Access Journals (Sweden)

N. Bender

2013-03-01

Full Text Available Cubic equations of state combined with excess Gibbs energy predictive models (like UNIFAC and equations of state based on applied statistical mechanics are among the main alternatives for phase equilibria prediction involving polar substances in wide temperature and pressure ranges. In this work, the predictive performances of the PC-SAFT with association contribution and Peng-Robinson (PR combined with UNIFAC (Do through mixing rules are compared. Binary and multi-component systems involving polar and non-polar substances were analyzed. Results were also compared to experimental data available in the literature. Results show a similar predictive performance for PC-SAFT with association and cubic equations combined with UNIFAC (Do through mixing rules. Although PC-SAFT with association requires less parameters, it is more complex and requires more computation time.

The complexities of complex span: explaining individual differences in working memory in children and adults.

Science.gov (United States)

Bayliss, Donna M; Jarrold, Christopher; Gunn, Deborah M; Baddeley, Alan D

2003-03-01

Two studies are presented that investigated the constraints underlying working memory performance in children and adults. In each case, independent measures of processing efficiency and storage capacity are assessed to determine their relative importance in predicting performance on complex span tasks,which measure working memory capacity. Results show that complex span performance was independently constrained by individual differences in domain-general processing efficiency and domain-specific storage capacity. Residual variance, which may reflect the ability to coordinate storage and processing, also predicted academic achievement. These results challenge the view that complex span taps a limited-capacity resource pool shared between processing and storage operations. Rather, they are consistent with a multiple-component model in which separate resource pools support the processing and storage functions of working memory.

Thyroid Uptake Measurement System

International Nuclear Information System (INIS)

Nguyen Duc Tuan; Nguyen Thi Bao My; Nguyen Van Sy

2007-01-01

The NED-UP.M7 is a complete thyroid uptake and analysis system specifically designed for nuclear medicine. Capable of performing a full range of studies this system provides fast, accurate results for Uptake Studies. The heart of the NED-UP.M7 is a microprocessor-controlled 2048 channel Compact Multi-Channel Analyzer, coupled to a 2 inch x 2 inch NaI(Tl) detector with a USB personal computer interface. The system offers simple, straight-forward operation using pre-programmed isotopes, and menudriven prompts to guide the user step by step through each procedure. The pre-programmed radionuclides include I-123, I-125, I-131, Tc-99m and Cs-137. The user-defined radionuclides also allow for isotope identification while the printer provides hard copy printouts for patient and department record keeping. The included software program running on PC (Windows XP-based) is a user friendly program with menudriven and graphic interface for easy controlling the system and managing measurement results of patient on Excel standard form. (author)

Initial operation of NSTX with plasma control

International Nuclear Information System (INIS)

Gates, D.; Bell, M.; Ferron, J.; Kaye, S.; Menard, J.; Mueller, D.; Neumeyer, C.; Sabbagh, S.

2000-01-01

First plasma, with a maximum current of 300kA, was achieved on NSTX in February 1999. These results were obtained using preprogrammed coil currents. The first controlled plasmas on NSTX were made starting in August 1999 with the full 1MA plasma current achieved in December 1999. The controlled quantities were plasma position (R, Z) and current (Ip). Variations in the plasma shape are achieved by adding preprogrammed currents to those determined by the control parameters. The control system is fully digital, with plasma position and current control, data acquisition, and power supply control all occurring in the same four-processor real time computer. The system uses the PCS (Plasma Control Software) system designed at General Atomics. Modular control algorithms, specific to NSTX, were written and incorporated into the PCS. The application algorithms do the actual control calculations, with the PCS handling data passing. The control system, including planned upgrades, will be described, along with results of the initial controlled plasma operations. Analysis of the performance of the control system will also be presented

General Synthesis of Transition-Metal Oxide Hollow Nanospheres/Nitrogen-Doped Graphene Hybrids by Metal-Ammine Complex Chemistry for High-Performance Lithium-Ion Batteries.

Science.gov (United States)

Chen, Jiayuan; Wu, Xiaofeng; Gong, Yan; Wang, Pengfei; Li, Wenhui; Mo, Shengpeng; Peng, Shengpan; Tan, Qiangqiang; Chen, Yunfa

2018-02-09

We present a general and facile synthesis strategy, on the basis of metal-ammine complex chemistry, for synthesizing hollow transition-metal oxides (Co 3 O 4 , NiO, CuO-Cu 2 O, and ZnO)/nitrogen-doped graphene hybrids, potentially applied in high-performance lithium-ion batteries. The oxygen-containing functional groups of graphene oxide play a prerequisite role in the formation of hollow transition-metal oxides on graphene nanosheets, and a significant hollowing process occurs only when forming metal (Co 2+ , Ni 2+ , Cu 2+ , or Zn 2+ )-ammine complex ions. Moreover, the hollowing process is well correlated with the complexing capacity between metal ions and NH 3 molecules. The significant hollowing process occurs for strong metal-ammine complex ions including Co 2+ , Ni 2+ , Cu 2+ , and Zn 2+ ions, and no hollow structures formed for weak and/or noncomplex Mn 2+ and Fe 3+ ions. Simultaneously, this novel strategy can also achieve the direct doping of nitrogen atoms into the graphene framework. The electrochemical performance of two typical hollow Co 3 O 4 or NiO/nitrogen-doped graphene hybrids was evaluated by their use as anodic materials. It was demonstrated that these unique nanostructured hybrids, in contrast with the bare counterparts, solid transition-metal oxides/nitrogen-doped graphene hybrids, perform with significantly improved specific capacity, superior rate capability, and excellent capacity retention. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Performance and Complexity of Tunable Sparse Network Coding with Gradual Growing Tuning Functions over Wireless Networks

DEFF Research Database (Denmark)

Garrido, Pablo; Sørensen, Chres Wiant; Roetter, Daniel Enrique Lucani

2016-01-01

Random Linear Network Coding (RLNC) has been shown to be a technique with several benefits, in particular when applied over wireless mesh networks, since it provides robustness against packet losses. On the other hand, Tunable Sparse Network Coding (TSNC) is a promising concept, which leverages...... a trade-off between computational complexity and goodput. An optimal density tuning function has not been found yet, due to the lack of a closed-form expression that links density, performance and computational cost. In addition, it would be difficult to implement, due to the feedback delay. In this work...

Building on the EGIPPS performance assessment: the multipolar framework as a heuristic to tackle the complexity of performance of public service oriented health care organisations.

Science.gov (United States)

Marchal, Bruno; Hoerée, Tom; da Silveira, Valéria Campos; Van Belle, Sara; Prashanth, Nuggehalli S; Kegels, Guy

2014-04-17

Performance of health care systems is a key concern of policy makers and health service managers all over the world. It is also a major challenge, given its multidimensional nature that easily leads to conceptual and methodological confusion. This is reflected by a scarcity of models that comprehensively analyse health system performance. In health, one of the most comprehensive performance frameworks was developed by the team of Leggat and Sicotte. Their framework integrates 4 key organisational functions (goal attainment, production, adaptation to the environment, and values and culture) and the tensions between these functions.We modified this framework to better fit the assessment of the performance of health organisations in the public service domain and propose an analytical strategy that takes it into the social complexity of health organisations. The resulting multipolar performance framework (MPF) is a meta-framework that facilitates the analysis of the relations and interactions between the multiple actors that influence the performance of health organisations. Using the MPF in a dynamic reiterative mode not only helps managers to identify the bottlenecks that hamper performance, but also the unintended effects and feedback loops that emerge. Similarly, it helps policymakers and programme managers at central level to better anticipate the potential results and side effects of and required conditions for health policies and programmes and to steer their implementation accordingly.

Cognitive performance modeling based on general systems performance theory.

Science.gov (United States)

Kondraske, George V

2010-01-01

General Systems Performance Theory (GSPT) was initially motivated by problems associated with quantifying different aspects of human performance. It has proved to be invaluable for measurement development and understanding quantitative relationships between human subsystem capacities and performance in complex tasks. It is now desired to bring focus to the application of GSPT to modeling of cognitive system performance. Previous studies involving two complex tasks (i.e., driving and performing laparoscopic surgery) and incorporating measures that are clearly related to cognitive performance (information processing speed and short-term memory capacity) were revisited. A GSPT-derived method of task analysis and performance prediction termed Nonlinear Causal Resource Analysis (NCRA) was employed to determine the demand on basic cognitive performance resources required to support different levels of complex task performance. This approach is presented as a means to determine a cognitive workload profile and the subsequent computation of a single number measure of cognitive workload (CW). Computation of CW may be a viable alternative to measuring it. Various possible "more basic" performance resources that contribute to cognitive system performance are discussed. It is concluded from this preliminary exploration that a GSPT-based approach can contribute to defining cognitive performance models that are useful for both individual subjects and specific groups (e.g., military pilots).

Trauma to the nail complex

Directory of Open Access Journals (Sweden)

Jefferson Braga Silva

2014-04-01

Full Text Available OBJECTIVE: to analyze the results from surgical intervention to treat trauma of the nail complex.METHODS: we retrospectively reviewed a series of 94 consecutive patients with trauma of the nail complex who were treated between 2000 and 2009. In 42 patients, nail bed suturing was performed. In 27 patients, nail bed suturing was performed subsequent to osteosynthesis of the distal phalanx. In 15, immediate grafting was performed, and in 10, late-stage grafting of the nail bed. The growth, size and shape of the nail were evaluated in comparison with the contralateral finger. The results were obtained by summing scores and classifying them as good, fair or poor.RESULTS: the results were considered to be good particularly in the patients who underwent nail bed suturing or nail bed suturing with osteosynthesis of the distal phalanx. Patients who underwent immediate or late-stage nail grafting had poor results.CONCLUSION: trauma of the nail complex without loss of substance presented better results than did deferred treatment for reconstruction of the nail complex.

Salt-induced phase separation for the determination of metals as their diethyldithiocarbamate complexes by high-performance liquid chromatography

International Nuclear Information System (INIS)

Mueller, B.J.; Lovett, R.J.

1987-01-01

Reversed-phase high-performance liquid chromatography with ultraviolet detection can be used to determine trace levels of Pt(II), Pd(II), Rh(III), Co(III), Ru(III), and Ir in aqueous solution following complexation with diethyldithiocarbamate. The metal complexes are extracted into acetonitrile from aqueous solution by the addition of a saturated salt solution. Quantitative metal recovery from aqueous solution is achievable for most metals for a wide solution pH range. Detection limits for the metals are <3 ng of metal/mL of original aqueous sample. Analyses of real samples are highly reproducible and sensitive. Ir an interfere in the determination of Pt(II) and Rh(III). A general protocol for chromatographic separation and determination of Pt(II), Pd(II), Rh(III), Ru(III), and Ir in aqueous solution is presented

Using LSTM recurrent neural networks for monitoring the LHC superconducting magnets

OpenAIRE

Wielgosz, Maciej; Skoczeń, Andrzej; Mertik, Matej

2016-01-01

The superconducting LHC magnets are coupled with an electronic monitoring system which records and analyzes voltage time series reflecting their performance. A currently used system is based on a range of preprogrammed triggers which launches protection procedures when a misbehavior of the magnets is detected. All the procedures used in the protection equipment were designed and implemented according to known working scenarios of the system and are updated and monitored by human operators. T...

Impact of automation: Measurement of performance, workload and behaviour in a complex control environment.

Science.gov (United States)

Balfe, Nora; Sharples, Sarah; Wilson, John R

2015-03-01

This paper describes an experiment that was undertaken to compare three levels of automation in rail signalling; a high level in which an automated agent set routes for trains using timetable information, a medium level in which trains were routed along pre-defined paths, and a low level where the operator (signaller) was responsible for the movement of all trains. These levels are described in terms of a Rail Automation Model based on previous automation theory (Parasuraman et al., 2000). Performance, subjective workload, and signaller activity were measured for each level of automation running under both normal operating conditions and abnormal, or disrupted, conditions. The results indicate that perceived workload, during both normal and disrupted phases of the experiment, decreased as the level of automation increased and performance was most consistent (i.e. showed the least variation between participants) with the highest level of automation. The results give a strong case in favour of automation, particularly in terms of demonstrating the potential for automation to reduce workload, but also suggest much benefit can achieved from a mid-level of automation potentially at a lower cost and complexity. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Complex Systems and Dependability

CERN Document Server

Zamojski, Wojciech; Sugier, Jaroslaw

2012-01-01

Typical contemporary complex system is a multifaceted amalgamation of technical, information, organization, software and human (users, administrators and management) resources. Complexity of such a system comes not only from its involved technical and organizational structure but mainly from complexity of information processes that must be implemented in the operational environment (data processing, monitoring, management, etc.). In such case traditional methods of reliability analysis focused mainly on technical level are usually insufficient in performance evaluation and more innovative meth

Real-Time and Real-Fast Performance of General-Purpose and Real-Time Operating Systems in Multithreaded Physical Simulation of Complex Mechanical Systems

Directory of Open Access Journals (Sweden)

Carlos Garre

2014-01-01

Full Text Available Physical simulation is a valuable tool in many fields of engineering for the tasks of design, prototyping, and testing. General-purpose operating systems (GPOS are designed for real-fast tasks, such as offline simulation of complex physical models that should finish as soon as possible. Interfacing hardware at a given rate (as in a hardware-in-the-loop test requires instead maximizing time determinism, for which real-time operating systems (RTOS are designed. In this paper, real-fast and real-time performance of RTOS and GPOS are compared when simulating models of high complexity with large time steps. This type of applications is usually present in the automotive industry and requires a good trade-off between real-fast and real-time performance. The performance of an RTOS and a GPOS is compared by running a tire model scalable on the number of degrees-of-freedom and parallel threads. The benchmark shows that the GPOS present better performance in real-fast runs but worse in real-time due to nonexplicit task switches and to the latency associated with interprocess communication (IPC and task switch.

Eye growth and myopia development: Unifying theory and Matlab model.

Science.gov (United States)

Hung, George K; Mahadas, Kausalendra; Mohammad, Faisal

2016-03-01

The aim of this article is to present an updated unifying theory of the mechanisms underlying eye growth and myopia development. A series of model simulation programs were developed to illustrate the mechanism of eye growth regulation and myopia development. Two fundamental processes are presumed to govern the relationship between physiological optics and eye growth: genetically pre-programmed signaling and blur feedback. Cornea/lens is considered to have only a genetically pre-programmed component, whereas eye growth is considered to have both a genetically pre-programmed and a blur feedback component. Moreover, based on the Incremental Retinal-Defocus Theory (IRDT), the rate of change of blur size provides the direction for blur-driven regulation. The various factors affecting eye growth are shown in 5 simulations: (1 - unregulated eye growth): blur feedback is rendered ineffective, as in the case of form deprivation, so there is only genetically pre-programmed eye growth, generally resulting in myopia; (2 - regulated eye growth): blur feedback regulation demonstrates the emmetropization process, with abnormally excessive or reduced eye growth leading to myopia and hyperopia, respectively; (3 - repeated near-far viewing): simulation of large-to-small change in blur size as seen in the accommodative stimulus/response function, and via IRDT as well as nearwork-induced transient myopia (NITM), leading to the development of myopia; (4 - neurochemical bulk flow and diffusion): release of dopamine from the inner plexiform layer of the retina, and the subsequent diffusion and relay of neurochemical cascade show that a decrease in dopamine results in a reduction of proteoglycan synthesis rate, which leads to myopia; (5 - Simulink model): model of genetically pre-programmed signaling and blur feedback components that allows for different input functions to simulate experimental manipulations that result in hyperopia, emmetropia, and myopia. These model simulation programs

Brain regions involved in voluntary movements as revealed by radioisotopic mapping of CBF or CMR-glucose changes

DEFF Research Database (Denmark)

Lassen, N A; Ingvar, D H

1990-01-01

Mapping of cortical and subcortical grey matter active during voluntary movements by means of measurements of local increases of CBF or CMR-Glucose is reviewed. Most of the studies concern observations in man during hand movements using the intracarotid Xenon-133 injection technique, an approach...... that only allows to image the cortex of the hemisphere on one side (the injected side) of the brain. The results show that simple static or repetitive movements mainly activate the contralateral primary hand area (MI and SI); complex preprogrammed or spontaneous purposeful movements the supplementary motor...... area SMA on both sides increase in CBF/CMR-glucose and even internally ("mentally") going through the trained movements, causes such changes; complex purposeful movements also activate the premotor cortex, a response that is bilateral with greatest response contralaterally. Studies in patients...

Identifying cognitive complexity factors affecting the complexity of procedural steps in emergency operating procedures of a nuclear power plant

International Nuclear Information System (INIS)

Park, Jinkyun; Jeong, Kwangsup; Jung, Wondea

2005-01-01

In complex systems such as a nuclear and chemical plant, it is well known that the provision of understandable procedures that allow operators to clarify what needs to be done and how to do it is one of the requisites to secure their safety. As a previous study in providing understandable procedures, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is raised. To this end, the comparisons between operators' performance data measured by the form of a step performance time with their behavior in carrying out the prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect an operator's cognitive burden are identified. Although a well-designed experiment is indispensable for confirming the appropriateness of the additional complexity factors, it is strongly believed that the change of operators' performance data can be more authentically explained if the additional complexity factors are taken into consideration

Identifying cognitive complexity factors affecting the complexity of procedural steps in emergency operating procedures of a nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Park, Jinkyun [Integrated Safety Assessment Division, Korea Atomic Energy Research Institute, P.O. Box 105, Duckjin-Dong, Yusong-Ku, Taejon 305-600 (Korea, Republic of)]. E-mail: kshpjk@kaeri.re.kr; Jeong, Kwangsup [Integrated Safety Assessment Division, Korea Atomic Energy Research Institute, P.O. Box 105, Duckjin-Dong, Yusong-Ku, Taejon 305-600 (Korea, Republic of); Jung, Wondea [Integrated Safety Assessment Division, Korea Atomic Energy Research Institute, P.O. Box 105, Duckjin-Dong, Yusong-Ku, Taejon 305-600 (Korea, Republic of)

2005-08-01

In complex systems such as a nuclear and chemical plant, it is well known that the provision of understandable procedures that allow operators to clarify what needs to be done and how to do it is one of the requisites to secure their safety. As a previous study in providing understandable procedures, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is raised. To this end, the comparisons between operators' performance data measured by the form of a step performance time with their behavior in carrying out the prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect an operator's cognitive burden are identified. Although a well-designed experiment is indispensable for confirming the appropriateness of the additional complexity factors, it is strongly believed that the change of operators' performance data can be more authentically explained if the additional complexity factors are taken into consideration.

Identifying cognitive complexity factors affecting the complexity of procedural steps in emergency operating procedures of a nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Jinkyun Park; Kwangsup Jeong; Wondea Jung [Korea Atomic Energy Research Institute, Taejon (Korea). Integrated Safety Assessment Division

2005-08-15

In complex systems such as a nuclear and chemical plant, it is well known that the provision of understandable procedures that allow operators to clarify what needs to be done and how to do it is one of the requisites to secure their safety. As a previous study in providing understandable procedures, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is raised. To this end, the comparisons between operator' performance data measured by the form of a step performance time with their behavior in carrying out the prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect an operator's cognitive burden are identified. Although a well-designed experiment is indispensable for confirming the appropriateness of the additional complexity factors, it is strongly believed that the change of operators' performance data can be more authentically explained if the additional complexity factors are taken into consideration. (author)

Study of complex modes

International Nuclear Information System (INIS)

Pastrnak, J.W.

1986-01-01

This eighteen-month study has been successful in providing the designer and analyst with qualitative guidelines on the occurrence of complex modes in the dynamics of linear structures, and also in developing computer codes for determining quantitatively which vibration modes are complex and to what degree. The presence of complex modes in a test structure has been verified. Finite element analysis of a structure with non-proportional dumping has been performed. A partial differential equation has been formed to eliminate possible modeling errors

Analysis of the existing Standard on Power performance measurement and its application in complex terrain

International Nuclear Information System (INIS)

Cuerva, A.

1997-01-01

There are some groups working on the improvement of the existing Standard and recommendation on WECS power performance measurement and analysis. One of them, besides the one working in this project, is the MEASNET expert group. This one is trying to adequate the main reference, the IEC1400-12 Ref. [9]. to the current requirements on technical quality and trueness. Within this group and the MEASNET one, many deficiencies have been detected in the procedure followed up to now. Several of them belong to general aspects of the method (calculations, assumptions, etc. ) but the most critical fact regards to the inherent characteristics of complex terrain and to the issue of site calibration and uncertainties due to it, specifically. (Author)

Analysis of the existing Standard on Power performance measurement and its application in complex terrain

Energy Technology Data Exchange (ETDEWEB)

Cuerva, A.

1997-10-01

There are some groups working on the improvement of the existing Standard and recommendation on WECS power performance measurement and analysis. One of them, besides the one working in this project, is the MEASNET expert group. This one is trying to adequate the main reference, the IEC 1400-12 Re.[9]. to the current requirements on technical quality and trueness. Within this group and the MEASNET one, many deficiencies have been detected in the procedure followed up to now. Several of them belong to general aspects of the method (calculations, assumptions, etc.) but the most critical fact regards to the inherent characteristics of complex terrain and to the issue of site calibration and uncertainties due to it, specifically. (Author)

A simple approach to enhance the performance of complex-coefficient filter-based PLL in grid-connected applications

DEFF Research Database (Denmark)

Ramezani, Malek; Golestan, Saeed; Li, Shuhui

2018-01-01

In recent years, a large number of three-phase phase-locked loops (PLLs) have been developed. One of the most popular ones is the complex coefficient filterbased PLL (CCF-PLL). The CCFs benefit from a sequence selective filtering ability and, hence, enable the CCF-PLL to selectively reject/extract...... disturbances before the PLL control loop while maintaining an acceptable dynamic behavior. The aim of this paper is presenting a simple yet effective approach to enhance the standard CCF-PLL performance without requiring any additional computational load....

Adaptive Beamforming Based on Complex Quaternion Processes

Directory of Open Access Journals (Sweden)

Jian-wu Tao

2014-01-01

Full Text Available Motivated by the benefits of array signal processing in quaternion domain, we investigate the problem of adaptive beamforming based on complex quaternion processes in this paper. First, a complex quaternion least-mean squares (CQLMS algorithm is proposed and its performance is analyzed. The CQLMS algorithm is suitable for adaptive beamforming of vector-sensor array. The weight vector update of CQLMS algorithm is derived based on the complex gradient, leading to lower computational complexity. Because the complex quaternion can exhibit the orthogonal structure of an electromagnetic vector-sensor in a natural way, a complex quaternion model in time domain is provided for a 3-component vector-sensor array. And the normalized adaptive beamformer using CQLMS is presented. Finally, simulation results are given to validate the performance of the proposed adaptive beamformer.

Performance and evaluation of a coupled prognostic model TAPM over a mountainous complex terrain industrial area

Science.gov (United States)

Matthaios, Vasileios N.; Triantafyllou, Athanasios G.; Albanis, Triantafyllos A.; Sakkas, Vasileios; Garas, Stelios

2018-05-01

Atmospheric modeling is considered an important tool with several applications such as prediction of air pollution levels, air quality management, and environmental impact assessment studies. Therefore, evaluation studies must be continuously made, in order to improve the accuracy and the approaches of the air quality models. In the present work, an attempt is made to examine the air pollution model (TAPM) efficiency in simulating the surface meteorology, as well as the SO2 concentrations in a mountainous complex terrain industrial area. Three configurations under different circumstances, firstly with default datasets, secondly with data assimilation, and thirdly with updated land use, ran in order to investigate the surface meteorology for a 3-year period (2009-2011) and one configuration applied to predict SO2 concentration levels for the year of 2011.The modeled hourly averaged meteorological and SO2 concentration values were statistically compared with those from five monitoring stations across the domain to evaluate the model's performance. Statistical measures showed that the surface temperature and relative humidity are predicted well in all three simulations, with index of agreement (IOA) higher than 0.94 and 0.70 correspondingly, in all monitoring sites, while an overprediction of extreme low temperature values is noted, with mountain altitudes to have an important role. However, the results also showed that the model's performance is related to the configuration regarding the wind. TAPM default dataset predicted better the wind variables in the center of the simulation than in the boundaries, while improvement in the boundary horizontal winds implied the performance of TAPM with updated land use. TAPM assimilation predicted the wind variables fairly good in the whole domain with IOA higher than 0.83 for the wind speed and higher than 0.85 for the horizontal wind components. Finally, the SO2 concentrations were assessed by the model with IOA varied from 0

Moessbauer study of iron-sugar complexes

International Nuclear Information System (INIS)

Tonkovic, M.; Music, S.; Hadzija, O.; Nagy-Czako, I.; Vertes, A.

1982-01-01

Ferric-fructose complex has been prepared using FeCl 3 and Fe(NO 3 ) 3 solutions. Molecular weight determination and Moessbauer spectroscopic measurements proved that the ferric-fructose complex is polymeric in solid state and also in aqueous solution. The synthesis of a new iron-sorbose complex has been performed. Its Moessbauer spectra indicate a structure similar to that of the iron-fructose complex. (author)

Metric for Calculation of System Complexity based on its Connections

Directory of Open Access Journals (Sweden)

João Ricardo Braga de Paiva

2017-02-01

Full Text Available This paper proposes a methodology based on system connections to calculate its complexity. Two study cases are proposed: the dining Chinese philosophers’ problem and the distribution center. Both studies are modeled using the theory of Discrete Event Systems and simulations in different contexts were performed in order to measure their complexities. The obtained results present i the static complexity as a limiting factor for the dynamic complexity, ii the lowest cost in terms of complexity for each unit of measure of the system performance and iii the output sensitivity to the input parameters. The associated complexity and performance measures aggregate knowledge about the system.

Team dynamics in complex projects

NARCIS (Netherlands)

Oeij, P.; Vroome, E.E.M. de; Dhondt, S.; Gaspersz, J.B.R.

2012-01-01

Complexity of projects is hotly debated and a factor which affects innovativeness of team performance. Much attention in the past is paid to technical complexity and many issues are related to natural and physical sciences. A growing awareness of the importance of socioorganisational issues is

Markov counting and reward processes for analysing the performance of a complex system subject to random inspections

International Nuclear Information System (INIS)

Ruiz-Castro, Juan Eloy

2016-01-01

In this paper, a discrete complex reliability system subject to internal failures and external shocks, is modelled algorithmically. Two types of internal failure are considered: repairable and non-repairable. When a repairable failure occurs, the unit goes to corrective repair. In addition, the unit is subject to external shocks that may produce an aggravation of the internal degradation level, cumulative damage or extreme failure. When a damage threshold is reached, the unit must be removed. When a non-repairable failure occurs, the device is replaced by a new, identical one. The internal performance and the external damage are partitioned in performance levels. Random inspections are carried out. When an inspection takes place, the internal performance of the system and the damage caused by external shocks are observed and if necessary the unit is sent to preventive maintenance. If the inspection observes minor state for the internal performance and/or external damage, then these states remain in memory when the unit goes to corrective or preventive maintenance. Transient and stationary analyses are performed. Markov counting and reward processes are developed in computational form to analyse the performance and profitability of the system with and without preventive maintenance. These aspects are implemented computationally with Matlab. - Highlights: • A multi-state device is modelled in an algorithmic and computational form. • The performance is partitioned in multi-states and degradation levels. • Several types of failures with repair times according to degradation levels. • Preventive maintenance as response to random inspection is introduced. • The performance-profitable is analysed through Markov counting and reward processes.

Iron complexes of pharmaceutical interest: Antianemics

Directory of Open Access Journals (Sweden)

Cakić Milorad D.

2003-01-01

Full Text Available Preparations based on different compounds of bi- and trivalent iron are curently used for the prevention and therapy of sideropenic anemia in human and veterinary medicine. The application of preparations based on dextran started about 1950. Up to now, synthesis and production of preparations were performed with the purpose of improving pharmacological performance by using dextran oligosaccharides with different weight - average molar masses and their oxidized and hydrogenated derivatives. Synthesis of polynuclear iron(lll complexs with other oligosaccharides (inulin and pullulan and their derivatives was developed, with potential or valid pharmacological activity for sideropenic anemia treatment.A Review of iron(lll complexes with different oligosaccharides, their physico-chemical characterization pharmaco-biological performance, global structure, further research and possible applications of then complexes, are presented in this paper.

Remote maintenance development

International Nuclear Information System (INIS)

Zook, C.R.

1979-01-01

The concept of remote maintenance as it pertains to nuclear fuel fabrication facilities is quite unique. The future may require completely remote facilities where maintenance will be performed by hybrid manipulators/robots. These units will be capable of being preprogrammed for automatic operation or manually operated with the operator becoming a part of the closed loop control system. These robots will mesh television, computer control, and direct force feedback manual control in a usable new concept of robotics

Performance of four Dactylorhiza species over a complex trophic gradient

NARCIS (Netherlands)

Dijk, E; Grootjans, AB

Spontananeous distribution and survival in experimental plots of four marsh orchids (Dactylorhiza spp.) in a hay-meadow complex were related to mineral composition of groundwater, soil nutrient availability and species composition of the vegetation. Differences in Ca2+ contents of the groundwater

Driver’s Cognitive Workload and Driving Performance under Traffic Sign Information Exposure in Complex Environments: A Case Study of the Highways in China

Directory of Open Access Journals (Sweden)

Nengchao Lyu

2017-02-01

Full Text Available Complex traffic situations and high driving workload are the leading contributing factors to traffic crashes. There is a strong correlation between driving performance and driving workload, such as visual workload from traffic signs on highway off-ramps. This study aimed to evaluate traffic safety by analyzing drivers’ behavior and performance under the cognitive workload in complex environment areas. First, the driving workload of drivers was tested based on traffic signs with different quantities of information. Forty-four drivers were recruited to conduct a traffic sign cognition experiment under static controlled environment conditions. Different complex traffic signs were used for applying the cognitive workload. The static experiment results reveal that workload is highly related to the amount of information on traffic signs and reaction time increases with the information grade, while driving experience and gender effect are not significant. This shows that the cognitive workload of subsequent driving experiments can be controlled by the amount of information on traffic signs. Second, driving characteristics and driving performance were analyzed under different secondary task driving workload levels using a driving simulator. Drivers were required to drive at the required speed on a designed highway off-ramp scene. The cognitive workload was controlled by reading traffic signs with different information, which were divided into four levels. Drivers had to make choices by pushing buttons after reading traffic signs. Meanwhile, the driving performance information was recorded. Questionnaires on objective workload were collected right after each driving task. The results show that speed maintenance and lane deviations are significantly different under different levels of cognitive workload, and the effects of driving experience and gender groups are significant. The research results can be used to analyze traffic safety in highway

Annual Performance Assessment of Complex Fenestration Systems in Sunny Climates Using Advanced Computer Simulations

Directory of Open Access Journals (Sweden)

Chantal Basurto

2015-12-01

Full Text Available Complex Fenestration Systems (CFS are advanced daylighting systems that are placed on the upper part of a window to improve the indoor daylight distribution within rooms. Due to their double function of daylight redirection and solar protection, they are considered as a solution to mitigate the unfavorable effects due to the admission of direct sunlight in buildings located in prevailing sunny climates (risk of glare and overheating. Accordingly, an adequate assessment of their performance should include an annual evaluation of the main aspects relevant to the use of daylight in such regions: the indoor illuminance distribution, thermal comfort, and visual comfort of the occupant’s. Such evaluation is possible with the use of computer simulations combined with the bi-directional scattering distribution function (BSDF data of these systems. This study explores the use of available methods to assess the visible and thermal annual performance of five different CFS using advanced computer simulations. To achieve results, an on-site daylight monitoring was carried out in a building located in a predominantly sunny climate location, and the collected data was used to create and calibrate a virtual model used to carry-out the simulations. The results can be employed to select the CFS, which improves visual and thermal interior environment for the occupants.

Falling with Style: Bats Perform Complex Aerial Rotations by Adjusting Wing Inertia.

Directory of Open Access Journals (Sweden)

Attila J Bergou

Full Text Available The remarkable maneuverability of flying animals results from precise movements of their highly specialized wings. Bats have evolved an impressive capacity to control their flight, in large part due to their ability to modulate wing shape, area, and angle of attack through many independently controlled joints. Bat wings, however, also contain many bones and relatively large muscles, and thus the ratio of bats' wing mass to their body mass is larger than it is for all other extant flyers. Although the inertia in bat wings would typically be associated with decreased aerial maneuverability, we show that bat maneuvers challenge this notion. We use a model-based tracking algorithm to measure the wing and body kinematics of bats performing complex aerial rotations. Using a minimal model of a bat with only six degrees of kinematic freedom, we show that bats can perform body rolls by selectively retracting one wing during the flapping cycle. We also show that this maneuver does not rely on aerodynamic forces, and furthermore that a fruit fly, with nearly massless wings, would not exhibit this effect. Similar results are shown for a pitching maneuver. Finally, we combine high-resolution kinematics of wing and body movements during landing and falling maneuvers with a 52-degree-of-freedom dynamical model of a bat to show that modulation of wing inertia plays the dominant role in reorienting the bat during landing and falling maneuvers, with minimal contribution from aerodynamic forces. Bats can, therefore, use their wings as multifunctional organs, capable of sophisticated aerodynamic and inertial dynamics not previously observed in other flying animals. This may also have implications for the control of aerial robotic vehicles.

Social dimension and complexity differentially influence brain responses during feedback processing.

Science.gov (United States)

Pfabigan, Daniela M; Gittenberger, Marianne; Lamm, Claus

2017-10-30

Recent research emphasizes the importance of social factors during performance monitoring. Thus, the current study investigated the impact of social stimuli -such as communicative gestures- on feedback processing. Moreover, it addressed a shortcoming of previous studies, which failed to consider stimulus complexity as potential confounding factor. Twenty-four volunteers performed a time estimation task while their electroencephalogram was recorded. Either social complex, social non-complex, non-social complex, or non-social non-complex stimuli were used to provide performance feedback. No effects of social dimension or complexity were found for task performance. In contrast, Feedback-Related Negativity (FRN) and P300 amplitudes were sensitive to both factors, with larger FRN and P300 amplitudes after social compared to non-social stimuli, and larger FRN amplitudes after complex positive than non-complex positive stimuli. P2 amplitudes were solely sensitive to feedback valence and social dimension. Subjectively, social complex stimuli were rated as more motivating than non-social complex ones. Independently of each other, social dimension and visual complexity influenced amplitude variation during performance monitoring. Social stimuli seem to be perceived as more salient, which is corroborated by P2, FRN and P300 results, as well as by subjective ratings. This could be explained due to their given relevance during every day social interactions.

Analysis of the low-level waste radionuclide inventory for the Radioactive Waste Management Complex performance assessment

Energy Technology Data Exchange (ETDEWEB)

Plansky, L.E.; Hoiland, S.A.

1992-02-01

This report summarizes the results of a study to improve the estimates of the radionuclides in the low-level radioactive waste (LLW) inventory which is buried in the Idaho National Engineering Laboratory (INEL) Radioactive Waste Management Complex (RWMC) Subsurface Disposal Area (SDA). The work is done to support the RWMC draft performance assessment (PA). Improved radionuclide inventory estimates are provided for the INEL LLW generators. Engineering, environmental assessment or other research areas may find use for the information in this report. It may also serve as a LLW inventory baseline for data quality assurance. The individual INEL LLW generators, their history and their activities are also described in detail.

Analysis of the low-level waste radionuclide inventory for the Radioactive Waste Management Complex performance assessment

International Nuclear Information System (INIS)

Plansky, L.E.; Hoiland, S.A.

1992-02-01

This report summarizes the results of a study to improve the estimates of the radionuclides in the low-level radioactive waste (LLW) inventory which is buried in the Idaho National Engineering Laboratory (INEL) Radioactive Waste Management Complex (RWMC) Subsurface Disposal Area (SDA). The work is done to support the RWMC draft performance assessment (PA). Improved radionuclide inventory estimates are provided for the INEL LLW generators. Engineering, environmental assessment or other research areas may find use for the information in this report. It may also serve as a LLW inventory baseline for data quality assurance. The individual INEL LLW generators, their history and their activities are also described in detail

Complexity measures of music

Science.gov (United States)

Pease, April; Mahmoodi, Korosh; West, Bruce J.

2018-03-01

We present a technique to search for the presence of crucial events in music, based on the analysis of the music volume. Earlier work on this issue was based on the assumption that crucial events correspond to the change of music notes, with the interesting result that the complexity index of the crucial events is mu ~ 2, which is the same inverse power-law index of the dynamics of the brain. The search technique analyzes music volume and confirms the results of the earlier work, thereby contributing to the explanation as to why the brain is sensitive to music, through the phenomenon of complexity matching. Complexity matching has recently been interpreted as the transfer of multifractality from one complex network to another. For this reason we also examine the mulifractality of music, with the observation that the multifractal spectrum of a computer performance is significantly narrower than the multifractal spectrum of a human performance of the same musical score. We conjecture that although crucial events are demonstrably important for information transmission, they alone are not suficient to define musicality, which is more adequately measured by the multifractality spectrum.

Bell Inequalities for Complex Networks

Science.gov (United States)

2015-10-26

AFRL-AFOSR-VA-TR-2015-0355 YIP Bell Inequalities for Complex Networks Greg Ver Steeg UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES Final Report 10/26...performance report PI: Greg Ver Steeg Young Investigator Award Grant Title: Bell Inequalities for Complex Networks Grant #: FA9550-12-1-0417 Reporting...October 20, 2015 Final Report for “Bell Inequalities for Complex Networks” Greg Ver Steeg Abstract This effort studied new methods to understand the effect

Conversation, coupling and complexity

DEFF Research Database (Denmark)

Fusaroli, Riccardo; Abney, Drew; Bahrami, Bahador

We investigate the linguistic co-construction of interpersonal synergies. By applying a measure of coupling between complex systems to an experimentally elicited corpus of joint decision dialogues, we show that interlocutors’ linguistic behavior displays increasing signature of multi-scale coupling......, known as complexity matching, over the course of interaction. Furthermore, we show that stronger coupling corresponds with more effective interaction, as measured by collective task performance....

Recent advances in improving performances of the lightweight complex hydrides Li-Mg-N-H system

Directory of Open Access Journals (Sweden)

Bao Zhang

2017-02-01

Full Text Available A brief review of state-of-the art advances in improving performances of the lightweight complex hydrides Li-Mg-N-H system is reported. Among the hydrogen storage materials, Li-Mg-N-H combination systems are regarded as one of the most potential candidates for the vehicular applications owing to their high hydrogen storage capacity (>5 wt% H and a more appropriate thermodynamic properties of hydrogen absorption and desorption. In the Li-Mg-N-H systems, tremendous efforts have been devoted to improving the hydrogen storage properties by adjusting composition, revealing reaction mechanisms, adding catalysts and refining the microstructures, etc. During the studies, different mechanisms, such as the coordinated two-molecule or multimolecule reaction mechanism and the ammonia-mediated mechanism, are proposed and applied under some certain conditions. Catalysis and nanosizing are very effective in enhancing the kinetic properties and thermodynamic destabilization of Li-Mg-N-H systems. Due to nano effects, the space-confinement and nanoconfinement seems to be more effective for improving the hydrogen storage performance, and it is great significant to develop hydrogen storage materials by studying the nanoconfined effects on the Li-Mg-N-H systems.

Studies concerning the preparation of the 153Sm complex with EDTMP (ethylenediaminetetra methylenephosphonic acid) and other 153Sm complexes with other phosphonates, at room temperature

International Nuclear Information System (INIS)

Gasiglia, Haroldo Taurian

2000-01-01

This work presents a study on the preparation of the complexes 1 53S m - EDTMP, 153 Sm - HEDP, 153 Sm - NTMP, 153 Sm - DTPMP and 153 Sm - HDTMP at room temperature. The preparation of the complex 153 Sm - HDTMP, under heating (70 - 72 deg C), was also studied. Several factors affecting the 153 Sm - EDTMP complexing yields were studied, due to its importance for use in Nuclear Medicine. These factors were: the molar ratio [ligand] / [metal], the ligand concentration and the incubation time of the mixture ligand-metal. The preparation of this complex, in low molar ratios, was also investigated. A study of the 153 Sm - EDTMP concerning the 'in vitro' stability, when this complex was prepared in low radioactive concentrations was performed. A study on the temperature influence on its degradation, when this complex was obtained in higher radioactive concentrations, was also performed. The preparation of the complexes 153 Sm - HEDP, 153 Sm - NTMP, 153 Sm - DTPMP and 153 Sm - HDTMP was investigated by preparing the complexes in two situations: high molar ratio and ligand concentration and low molar ratio and ligand concentration. The 'in vitro' stability of each complex, obtained in low radioactive concentration was studied. In the specific case of the complex 153 Sm - HDTMP, its biological distribution in mice was performed. All the complexes were investigated by high performance liquid chromatography (HPLC) and its complexing yields were determined by other three chromatographic processes: ionic exchange, thin layer chromatography (TLC - SG) and paper chromatography. The chromatographic processes were performed by association with specific radiochemical techniques. This work also presents a comparative study on the chromatograms obtained by thin layer chromatography (TLC - SG) and paper chromatography, when evaluated by the technique of cutting the strips into pieces and the chromatograms performed directly on a radiochromatography. The shape of the chromatograms and R

Chitosan–Zinc(II Complexes as a Bio-Sorbent for the Adsorptive Abatement of Phosphate: Mechanism of Complexation and Assessment of Adsorption Performance

Directory of Open Access Journals (Sweden)

Maryam Roza Yazdani

2017-12-01

Full Text Available This study examines zinc(II–chitosan complexes as a bio-sorbent for phosphate removal from aqueous solutions. The bio-sorbent is prepared and is characterized via Fourier Transform Infrared Spectroscopy (FT-IR, Scanning Electron Microscopy (SEM, and Point of Zero Charge (pHPZC–drift method. The adsorption capacity of zinc(II–chitosan bio-sorbent is compared with those of chitosan and ZnO–chitosan and nano-ZnO–chitosan composites. The effect of operational parameters including pH, temperature, and competing ions are explored via adsorption batch mode. A rapid phosphate uptake is observed within the first three hours of contact time. Phosphate removal by zinc(II–chitosan is favored when the surface charge of bio-sorbent is positive/or neutral e.g., within the pH range inferior or around its pHPZC, 7. Phosphate abatement is enhanced with decreasing temperature. The study of background ions indicates a minor effect of chloride, whereas nitrate and sulfate show competing effect with phosphate for the adsorptive sites. The adsorption kinetics is best described with the pseudo-second-order model. Sips (R2 > 0.96 and Freundlich (R2 ≥ 0.95 models suit the adsorption isotherm. The phosphate reaction with zinc(II–chitosan is exothermic, favorable and spontaneous. The complexation of zinc(II and chitosan along with the corresponding mechanisms of phosphate removal are presented. This study indicates the introduction of zinc(II ions into chitosan improves its performance towards phosphate uptake from 1.45 to 6.55 mg/g and provides fundamental information for developing bio-based materials for water remediation.

Hydrodynamic Data for Manoeuvring and Control of an AUV Determined by Tank Tests and Free-Sailing Trials

DEFF Research Database (Denmark)

Aage, Christian

1998-01-01

Autonomous Underwater Vehicles (AUV's) can be used for a large number of subsea acitivities in different modes of operation varying from the ROV-mode with on-line control and power supply from the surface, to the true AUV-mode where the vehicle performs its pre-programmed tasks with full autonomy...... manoeuvres, such as turning circles and zigzag tests. Similar free-sailing manoeuvrability trials are described and compared to the simulations. The free-sailing manoeuvres were monitored by the Differential Global Positioning System (DGPS)....

Why performance-based contracting failed in Uganda--an "open-box" evaluation of a complex health system intervention.

Science.gov (United States)

Ssengooba, Freddie; McPake, Barbara; Palmer, Natasha

2012-07-01

Performance-based contracting (PBC) is a tool that links rewards to attainment of measurable performance targets. Significant problems remain in the methods used to evaluate this tool. The primary focus of evaluations on the effects of PBC (black-box) and less attention to how these effects arise (open-box) generates suboptimal policy learning. A black-box impact evaluation of PBC pilot by the Development Research Group of the World Bank (DRG) and the Ministry of Health (MOH) concluded that PBC was ineffective. This paper reports a theory-based case study intended to clarify how and why PBC failed to achieve its objectives. To explain the observed PBC implementation and responses of participants, this case study employed two related theories i.e. complex adaptive system and expectancy theory respectively. A prospective study trailed the implementation of PBC (2003-2006) while collecting experiences of participants at district and hospital levels. Significant problems were encountered in the implementation of PBC that reflected its inadequate design. As problems were encountered, hasty adaptations resulted in a de facto intervention distinct from the one implied at the design stage. For example, inadequate time was allowed for the selection of service targets by the health centres yet they got 'locked-in' to these poor choices. The learning curve and workload among performance auditors weakened the validity of audit results. Above all, financial shortfalls led to delays, short-cuts and uncertainty about the size and payment of bonuses. The lesson for those intending to implement similar interventions is that PBC should not be attempted 'on the cheap'. It requires a plan to boost local institutional and technical capacities of implementers. It also requires careful consideration of the responses of multiple actors - both insiders and outsiders to the intended change process. Given the costs and complexity of PBC implementation, strengthening conventional approaches

Bureaucratic Complexity and Impacts of Corruption in Utilities

OpenAIRE

Tøndel, Line; Søreide, Tina

2008-01-01

This paper explores how the relationship between bureaucratic complexity and corruption affects the performance in utilities. We observe considerable variation in the performance of the utilities across countries, also across countries which appear to be relatively similar in terms of GDP per capita. Our hypothesis is that corruption is an important explanatory factor. In particular, corruption coupled with a complex regulatory structure can have negative effects on performance in this sector...

Model for measuring complex performance in an aviation environment

International Nuclear Information System (INIS)

Hahn, H.A.

1988-01-01

An experiment was conducted to identify models of pilot performance through the attainment and analysis of concurrent verbal protocols. Sixteen models were identified. Novice and expert pilots differed with respect to the models they used. Models were correlated to performance, particularly in the case of expert subjects. Models were not correlated to performance shaping factors (i.e. workload). 3 refs., 1 tab

A FPGA-Based Broadband EIT System for Complex Bioimpedance Measurements—Design and Performance Estimation

Directory of Open Access Journals (Sweden)

Roman Kusche

2015-07-01

Full Text Available Electrical impedance tomography (EIT is an imaging method that is able to estimate the electrical conductivity distribution of living tissue. This work presents a field programmable gate array (FPGA-based multi-frequency EIT system for complex, time-resolved bioimpedance measurements. The system has the capability to work with measurement setups with up to 16 current electrodes and 16 voltage electrodes. The excitation current has a range of about 10 µA to 5 mA, whereas the sinusoidal signal used for excitation can have a frequency of up to 500 kHz. Additionally, the usage of a chirp or rectangular signal excitation is possible. Furthermore, the described system has a sample rate of up to 3480 impedance spectra per second (ISPS. The performance of the EIT system is demonstrated with a resistor-based phantom and tank phantoms. Additionally, first measurements taken from the human thorax during a breathing cycle are presented.

Training complex judgment: The effects of critical thinking and complex judgment

NARCIS (Netherlands)

Helsdingen, Anne; Van Gog, Tamara; Van Merriënboer, Jeroen

2010-01-01

Helsdingen, A. S., Van Gog, T., & Van Merrienboer, J. J. G. (2009). Training complex judgment: The effects of critical thinking and contextual interference. Paper presented at the International Center for Learning, Education and Performance Systems (ICLEPS). Talahassee, Florida: Florida State

A Qualitative Method to Estimate HSI Display Complexity

International Nuclear Information System (INIS)

Hugo, Jacques; Gertman, David

2013-01-01

There is mounting evidence that complex computer system displays in control rooms contribute to cognitive complexity and, thus, to the probability of human error. Research shows that reaction time increases and response accuracy decreases as the number of elements in the display screen increase. However, in terms of supporting the control room operator, approaches focusing on addressing display complexity solely in terms of information density and its location and patterning, will fall short of delivering a properly designed interface. This paper argues that information complexity and semantic complexity are mandatory components when considering display complexity and that the addition of these concepts assists in understanding and resolving differences between designers and the preferences and performance of operators. This paper concludes that a number of simplified methods, when combined, can be used to estimate the impact that a particular display may have on the operator's ability to perform a function accurately and effectively. We present a mixed qualitative and quantitative approach and a method for complexity estimation

Complex terrain and wind lidars

Energy Technology Data Exchange (ETDEWEB)

Bingoel, F.

2009-08-15

This thesis includes the results of a PhD study about complex terrain and wind lidars. The study mostly focuses on hilly and forested areas. Lidars have been used in combination with cups, sonics and vanes, to reach the desired vertical measurement heights. Several experiments are performed in complex terrain sites and the measurements are compared with two different flow models; a linearised flow model LINCOM and specialised forest model SCADIS. In respect to the lidar performance in complex terrain, the results showed that horizontal wind speed errors measured by a conically scanning lidar can be of the order of 3-4% in moderately-complex terrain and up to 10% in complex terrain. The findings were based on experiments involving collocated lidars and meteorological masts, together with flow calculations over the same terrains. The lidar performance was also simulated with the commercial software WAsP Engineering 2.0 and was well predicted except for some sectors where the terrain is particularly steep. Subsequently, two experiments were performed in forested areas; where the measurements are recorded at a location deep-in forest and at the forest edge. Both sites were modelled with flow models and the comparison of the measurement data with the flow model outputs showed that the mean wind speed calculated by LINCOM model was only reliable between 1 and 2 tree height (h) above canopy. The SCADIS model reported better correlation with the measurements in forest up to approx6h. At the forest edge, LINCOM model was used by allocating a slope half-in half out of the forest based on the suggestions of previous studies. The optimum slope angle was reported as 17 deg.. Thus, a suggestion was made to use WAsP Engineering 2.0 for forest edge modelling with known limitations and the applied method. The SCADIS model worked better than the LINCOM model at the forest edge but the model reported closer results to the measurements at upwind than the downwind and this should be

CyNC - towards a General Tool for Performance Analysis of Complex Distributed Real Time Systems

DEFF Research Database (Denmark)

Schiøler, Henrik; Jessen, Jan Jakob; Nielsen, Jens F. Dalsgaard

2005-01-01

The paper addresses the current state and the ongoing activities of a tool for performance analysis of complex real time systems. The tool named CyNC is based on network calculus allowing for the computation of backlogs and delays in a system from specified lower and upper bounds of external...... workflow and computational resources. The current version of the tool implements an extension to previous work in that it allows for general workflow and resource bounds and provides optimal solutions even to systems with cyclic dependencies. Despite the virtues of the current tool, improvements...... and extensions still remain, which are in focus of ongoing activities. Improvements include accounting for phase information to improve bounds, whereas the tool awaits extension to include flow control models, which both depend on the possibility of accounting for propagation delay. Since the current version...

Self-Assembly of Octopus Nanoparticles into Pre-Programmed Finite Clusters

Science.gov (United States)

Halverson, Jonathan; Tkachenko, Alexei

2012-02-01

The precise control of the spatial arrangement of nanoparticles (NP) is often required to take full advantage of their novel optical and electronic properties. NPs have been shown to self-assemble into crystalline structures using either patchy surface regions or complementary DNA strands to direct the assembly. Due to a lack of specificity of the interactions these methods lead to only a limited number of structures. An emerging approach is to bind ssDNA at specific sites on the particle surface making so-called octopus NPs. Using octopus NPs we investigate the inverse problem of the self-assembly of finite clusters. That is, for a given target cluster (e.g., arranging the NPs on the vertices of a dodecahedron) what are the minimum number of complementary DNA strands needed for the robust self-assembly of the cluster from an initially homogeneous NP solution? Based on the results of Brownian dynamics simulations we have compiled a set of design rules for various target clusters including cubes, pyramids, dodecahedrons and truncated icosahedrons. Our approach leads to control over the kinetic pathway and has demonstrated nearly perfect yield of the target.

Performance-complexity tradeoff in sequential decoding for the unconstrained AWGN channel

KAUST Repository

Abediseid, Walid; Alouini, Mohamed-Slim

2013-01-01

channel has been studied only under the use of the minimum Euclidean distance decoder that is commonly referred to as the lattice decoder. Lattice decoders based on solutions to the NP-hard closest vector problem are very complex to implement

Supply chain integration and performance : the moderating effect of supply complexity

NARCIS (Netherlands)

Giménez, C.; van der Vaart, T.; van Donk, D.P.

2012-01-01

Purpose - The purpose of this paper is to investigate the effectiveness of supply chain integration in different contexts. More specifically, it aims to show that supply chain integration is only effective in buyer-supplier relationships characterised by high supply complexity.

Cyclometallated ruthenium(II) carbonyl complexes with 1 ...

Indian Academy of Sciences (India)

The characterization of the complexes having the ... Electronic spectra of the complexes display multiple strong absorptions in the ... Microanalyses (CHN) were performed by using a ..... proton.47,49 Absence of this signal in the spectra of.

High performance parallel computing of flows in complex geometries: I. Methods

International Nuclear Information System (INIS)

Gourdain, N; Gicquel, L; Montagnac, M; Vermorel, O; Staffelbach, G; Garcia, M; Boussuge, J-F; Gazaix, M; Poinsot, T

2009-01-01

Efficient numerical tools coupled with high-performance computers, have become a key element of the design process in the fields of energy supply and transportation. However flow phenomena that occur in complex systems such as gas turbines and aircrafts are still not understood mainly because of the models that are needed. In fact, most computational fluid dynamics (CFD) predictions as found today in industry focus on a reduced or simplified version of the real system (such as a periodic sector) and are usually solved with a steady-state assumption. This paper shows how to overcome such barriers and how such a new challenge can be addressed by developing flow solvers running on high-end computing platforms, using thousands of computing cores. Parallel strategies used by modern flow solvers are discussed with particular emphases on mesh-partitioning, load balancing and communication. Two examples are used to illustrate these concepts: a multi-block structured code and an unstructured code. Parallel computing strategies used with both flow solvers are detailed and compared. This comparison indicates that mesh-partitioning and load balancing are more straightforward with unstructured grids than with multi-block structured meshes. However, the mesh-partitioning stage can be challenging for unstructured grids, mainly due to memory limitations of the newly developed massively parallel architectures. Finally, detailed investigations show that the impact of mesh-partitioning on the numerical CFD solutions, due to rounding errors and block splitting, may be of importance and should be accurately addressed before qualifying massively parallel CFD tools for a routine industrial use.

A Qualitative Method to Estimate HSI Display Complexity

Energy Technology Data Exchange (ETDEWEB)

Hugo, Jacques; Gertman, David [Idaho National Laboratory, Idaho (United States)

2013-04-15

There is mounting evidence that complex computer system displays in control rooms contribute to cognitive complexity and, thus, to the probability of human error. Research shows that reaction time increases and response accuracy decreases as the number of elements in the display screen increase. However, in terms of supporting the control room operator, approaches focusing on addressing display complexity solely in terms of information density and its location and patterning, will fall short of delivering a properly designed interface. This paper argues that information complexity and semantic complexity are mandatory components when considering display complexity and that the addition of these concepts assists in understanding and resolving differences between designers and the preferences and performance of operators. This paper concludes that a number of simplified methods, when combined, can be used to estimate the impact that a particular display may have on the operator's ability to perform a function accurately and effectively. We present a mixed qualitative and quantitative approach and a method for complexity estimation.

Crystal structures and catalytic performance of three new methoxy substituted salen type nickel(II) Schiff base complexes derived from meso-1,2-diphenyl-1,2-ethylenediamine

Science.gov (United States)

Ghaffari, Abolfazl; Behzad, Mahdi; Pooyan, Mahsa; Amiri Rudbari, Hadi; Bruno, Giuseppe

2014-04-01

Three new nickel(II) complexes of a series of methoxy substituted salen type Schiff base ligands were synthesized and characterized by IR, UV-Vis and 1H NMR spectroscopy and elemental analysis. The ligands were synthesized from the condensation of meso-1,2-diphenyl-1,2-ethylenediamine with n-methoxysalicylaldehyde (n = 3, 4 and 5). Crystal structures of these complexes were determined. Electrochemical behavior of the complexes was studied by means of cyclic voltammetry in DMSO solutions. Catalytic performance of the complexes was studied in the epoxidation of cyclooctene using tert-butylhydroperoxide (TBHP) as oxidant under various conditions to find the optimum operating parameters. Low catalytic activity with moderate epoxide selectivity was observed in in-solvent conditions but in the solvent-free conditions, enhanced catalytic activity with high epoxide selectivity was achieved.

Reduced-Complexity Deterministic Annealing for Vector Quantizer Design

Directory of Open Access Journals (Sweden)

Ortega Antonio

2005-01-01

Full Text Available This paper presents a reduced-complexity deterministic annealing (DA approach for vector quantizer (VQ design by using soft information processing with simplified assignment measures. Low-complexity distributions are designed to mimic the Gibbs distribution, where the latter is the optimal distribution used in the standard DA method. These low-complexity distributions are simple enough to facilitate fast computation, but at the same time they can closely approximate the Gibbs distribution to result in near-optimal performance. We have also derived the theoretical performance loss at a given system entropy due to using the simple soft measures instead of the optimal Gibbs measure. We use thederived result to obtain optimal annealing schedules for the simple soft measures that approximate the annealing schedule for the optimal Gibbs distribution. The proposed reduced-complexity DA algorithms have significantly improved the quality of the final codebooks compared to the generalized Lloyd algorithm and standard stochastic relaxation techniques, both with and without the pairwise nearest neighbor (PNN codebook initialization. The proposed algorithms are able to evade the local minima and the results show that they are not sensitive to the choice of the initial codebook. Compared to the standard DA approach, the reduced-complexity DA algorithms can operate over 100 times faster with negligible performance difference. For example, for the design of a 16-dimensional vector quantizer having a rate of 0.4375 bit/sample for Gaussian source, the standard DA algorithm achieved 3.60 dB performance in 16 483 CPU seconds, whereas the reduced-complexity DA algorithm achieved the same performance in 136 CPU seconds. Other than VQ design, the DA techniques are applicable to problems such as classification, clustering, and resource allocation.

The carbonate complexation of plutonium(IV)

International Nuclear Information System (INIS)

Hobart, D.E.; Palmer, P.D.; Newton, T.W.

1985-01-01

Plutonium(IV) carbonate complexes are expected to be of particular importance in typical groundwaters at the Yucca Mountain site of the candidate nuclear waste repository being studied by the Nevada Nuclear Waste Storage Investigations Project. The chemistry of these complexes is also important in the areas of nuclear fuel reprocessing and purification, actinide separations, and environmental studies. This report describes initial experiments performed to determine the identity and equilibrium quotients of plutonium(IV) carbonate complexes. These experiments were performed at pH values between 7.2 and 9.6 using a spectrophotometric method. In addition, a brief review of the published literature on Pu(IV) carbonate complexes is presented. Since Pu(IV) exhibits low solubility in the near-neutral pH range, a complex-competition reaction where citrate ligands compete with carbonate ions for the plutonium will be employed. This will permit us to study the pure carbonate system; study the mixed carbonate/citrate system, and confirm and extend the literature work on the pure citrate system. The current experiments have demonstrated the existence of at least three distinct species in the pH region studied. This work will continue in the extended study of the pure citrate system, followed by the investigation of the citrate/carbonate complex/competition reaction. 9 refs., 4 figs., 2 tabs

Embedded image processing engine using ARM cortex-M4 based STM32F407 microcontroller

International Nuclear Information System (INIS)

Samaiya, Devesh

2014-01-01

Due to advancement in low cost, easily available, yet powerful hardware and revolution in open source software, urge to make newer, more interactive machines and electronic systems have increased manifold among engineers. To make system more interactive, designers need easy to use sensor systems. Giving the boon of vision to machines was never easy, though it is not impossible these days; it is still not easy and expensive. This work presents a low cost, moderate performance and programmable Image processing engine. This Image processing engine is able to capture real time images, can store the images in the permanent storage and can perform preprogrammed image processing operations on the captured images

Embedded image processing engine using ARM cortex-M4 based STM32F407 microcontroller

Energy Technology Data Exchange (ETDEWEB)

Samaiya, Devesh, E-mail: samaiya.devesh@gmail.com [Assistant Professor, School of Technology, The Glocal University, Mirzapur Pole, Saharanpur, Uttar Pradesh (India)

2014-10-06

Due to advancement in low cost, easily available, yet powerful hardware and revolution in open source software, urge to make newer, more interactive machines and electronic systems have increased manifold among engineers. To make system more interactive, designers need easy to use sensor systems. Giving the boon of vision to machines was never easy, though it is not impossible these days; it is still not easy and expensive. This work presents a low cost, moderate performance and programmable Image processing engine. This Image processing engine is able to capture real time images, can store the images in the permanent storage and can perform preprogrammed image processing operations on the captured images.

A deep learning approach for fetal QRS complex detection.

Science.gov (United States)

Zhong, Wei; Liao, Lijuan; Guo, Xuemei; Wang, Guoli

2018-04-20

Non-invasive foetal electrocardiography (NI-FECG) has the potential to provide more additional clinical information for detecting and diagnosing fetal diseases. We propose and demonstrate a deep learning approach for fetal QRS complex detection from raw NI-FECG signals by using a convolutional neural network (CNN) model. The main objective is to investigate whether reliable fetal QRS complex detection performance can still be obtained from features of single-channel NI-FECG signals, without canceling maternal ECG (MECG) signals. A deep learning method is proposed for recognizing fetal QRS complexes. Firstly, we collect data from set-a of the PhysioNet/computing in Cardiology Challenge database. The sample entropy method is used for signal quality assessment. Part of the bad quality signals is excluded in the further analysis. Secondly, in the proposed method, the features of raw NI-FECG signals are normalized before they are fed to a CNN classifier to perform fetal QRS complex detection. We use precision, recall, F-measure and accuracy as the evaluation metrics to assess the performance of fetal QRS complex detection. The proposed deep learning method can achieve relatively high precision (75.33%), recall (80.54%), and F-measure scores (77.85%) compared with three other well-known pattern classification methods, namely KNN, naive Bayes and SVM. the proposed deep learning method can attain reliable fetal QRS complex detection performance from the raw NI-FECG signals without canceling MECG signals. In addition, the influence of different activation functions and signal quality assessment on classification performance are evaluated, and results show that Relu outperforms the Sigmoid and Tanh on this particular task, and better classification performance is obtained with the signal quality assessment step in this study.

Scalable high-performance algorithm for the simulation of exciton-dynamics. Application to the light harvesting complex II in the presence of resonant vibrational modes

DEFF Research Database (Denmark)

Kreisbeck, Christoph; Kramer, Tobias; Aspuru-Guzik, Alán

2014-01-01

high-performance many-core platforms using the Open Compute Language (OpenCL). For the light-harvesting complex II (LHC II) found in spinach, the HEOM results deviate from predictions of approximate theories and clarify the time-scale of the transfer-process. We investigate the impact of resonantly...

ASIC For Complex Fixed-Point Arithmetic

Science.gov (United States)

Petilli, Stephen G.; Grimm, Michael J.; Olson, Erlend M.

1995-01-01

Application-specific integrated circuit (ASIC) performs 24-bit, fixed-point arithmetic operations on arrays of complex-valued input data. High-performance, wide-band arithmetic logic unit (ALU) designed for use in computing fast Fourier transforms (FFTs) and for performing ditigal filtering functions. Other applications include general computations involved in analysis of spectra and digital signal processing.

Communication complexity and information complexity

Science.gov (United States)

Pankratov, Denis

Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

Motor preparation is modulated by the resolution of the response timing information.

Science.gov (United States)

Carlsen, Anthony N; Mackinnon, Colum D

2010-03-31

In the present experiment, the temporal predictability of response time was systematically manipulated to examine its effect on the time course of motor pre-programming and release of the intended movement by an acoustic startle stimulus. Participants performed a ballistic right wrist extension task in four different temporal conditions: 1) a variable foreperiod simple RT task, 2) a fixed foreperiod simple RT task, 3) a low resolution countdown anticipation-timing task, and 4) a high resolution anticipation-timing task. For each task, a startling acoustic stimulus (124dB) was presented at several intervals prior to the "go" signal ("go" -150ms, -500ms, and -1500ms). Results from the startle trials showed that the time course of movement pre-programming was affected by the temporal uncertainty of the imperative "go" cue. These findings demonstrate that the resolution of the timing information regarding the response cue has a marked effect on the timing of movement preparation such that under conditions of low temporal resolution, participants plan the movement well in advance in accordance with the anticipated probability of onset of the cue, whereas movement preparation is delayed until less than 500ms prior to response time when continuous temporal information is provided. Copyright 2010 Elsevier B.V. All rights reserved.

From metamorphosis to maturity in complex life cycles: equal performance of different juvenile life history pathways.

Science.gov (United States)

Schmidt, Benedikt R; Hödl, Walter; Schaub, Michael

2012-03-01

Performance in one stage of a complex life cycle may affect performance in the subsequent stage. Animals that start a new stage at a smaller size than conspecifics may either always remain smaller or they may be able to "catch up" through plasticity, usually elevated growth rates. We study how size at and date of metamorphosis affected subsequent performance in the terrestrial juvenile stage and lifetime fitness of spadefoot toads (Pelobates fuscus). We analyzed capture-recapture data of > 3000 individuals sampled during nine years with mark-recapture models to estimate first-year juvenile survival probabilities and age-specific first-time breeding probabilities of toads, followed by model selection to assess whether these probabilities were correlated with size at and date of metamorphosis. Males attained maturity after two years, whereas females reached maturity 2-4 years after metamorphosis. Age at maturity was weakly correlated with metamorphic traits. In both sexes, first-year juvenile survival depended positively on date of metamorphosis and, in males, also negatively on size at metamorphosis. In males, toads that metamorphosed early at a small size had the highest probability to reach maturity. However, because very few toadlets metamorphosed early, the vast majority of male metamorphs had a very similar probability to reach maturity. A matrix projection model constructed for females showed that different juvenile life history pathways resulted in similar lifetime fitness. We found that the effects of date of and size at metamorphosis on different juvenile traits cancelled each other out such that toads that were small or large at metamorphosis had equal performance. Because the costs and benefits of juvenile life history pathways may also depend on population fluctuations, ample phenotypic variation in life history traits may be maintained.

Compressive Sensing Based Bayesian Sparse Channel Estimation for OFDM Communication Systems: High Performance and Low Complexity

Science.gov (United States)

Xu, Li; Shan, Lin; Adachi, Fumiyuki

2014-01-01

In orthogonal frequency division modulation (OFDM) communication systems, channel state information (CSI) is required at receiver due to the fact that frequency-selective fading channel leads to disgusting intersymbol interference (ISI) over data transmission. Broadband channel model is often described by very few dominant channel taps and they can be probed by compressive sensing based sparse channel estimation (SCE) methods, for example, orthogonal matching pursuit algorithm, which can take the advantage of sparse structure effectively in the channel as for prior information. However, these developed methods are vulnerable to both noise interference and column coherence of training signal matrix. In other words, the primary objective of these conventional methods is to catch the dominant channel taps without a report of posterior channel uncertainty. To improve the estimation performance, we proposed a compressive sensing based Bayesian sparse channel estimation (BSCE) method which cannot only exploit the channel sparsity but also mitigate the unexpected channel uncertainty without scarifying any computational complexity. The proposed method can reveal potential ambiguity among multiple channel estimators that are ambiguous due to observation noise or correlation interference among columns in the training matrix. Computer simulations show that proposed method can improve the estimation performance when comparing with conventional SCE methods. PMID:24983012

Post-weaning and whole-of-life performance of pigs is determined by live weight at weaning and the complexity of the diet fed after weaning

Directory of Open Access Journals (Sweden)

Cherie L. Collins

2017-12-01

Full Text Available The production performance and financial outcomes associated with weaner diet complexity for pigs of different weight classes at weaning were examined in this experiment. A total of 720 weaner pigs (360 entire males and 360 females were selected at weaning (27 ± 3 d and allocated to pens of 10 based on individual weaning weight (light weaning weight: pigs below 6.5 kg; medium weaning weight: 6.5 to 8 kg; heavy weaning weight: above 8.5 kg. Pens were then allocated in a 3 × 2 × 2 factorial arrangement of treatments with the respective factors being weaning weight (heavy, medium and light; H, M and L, respectively, weaner diet complexity (high complexity/cost, HC; low complexity/cost, LC, and gender (male and female. Common diets were fed to both treatment groups during the final 4 weeks of the weaner period (a period of 39 days. In the first 6 d after weaning, pigs offered the HC diets gained weight faster and used feed more efficiently than those offered the LC diets (P = 0.031. Pigs fed a HC diet after weaning tended to be heavier at the sale live weight of 123 d of age compared with pigs fed the LC diet (P = 0.056. There were no other main effects of the feeding program on growth performance through to slaughter. Weaning weight had a profound influence on lifetime growth performance and weight at 123 d of age, with H pigs at weaning increasing their weight advantage over the M and L pigs (101.3, 97.1, 89.6 kg respectively, P < 0.001. Cost-benefit analyses suggested there was a minimal benefit in terms of cost per unit live weight gain over lifetime when pigs were offered a HC feeding program to L, with a lower feed cost/kg gain. The results from this investigation confirm the impact of weaning weight on lifetime growth performance, and suggest that a HC feeding program should be focused on L weaner pigs (i.e., weaning weight less than 6.5 kg at 27 d of age in order to maximise financial returns.

Visual-Motor Control in Baseball Batting

Directory of Open Access Journals (Sweden)

Rob Gray

2011-05-01

Full Text Available With margins for error of a few milliseconds and fractions of an inch it is not surprising that hitting a baseball is considered to be one of the most difficult acts in all of sports. We have been investigating this challenging behavior using a virtual baseball batting setup in which simulations of an approaching ball, pitcher, and field are combined with real-time recording of bat and limb movements. I will present evidence that baseball batting involves variable pre-programmed control in which the swing direction and movement time (MT are set prior to the initiation of the action but can take different values from swing-to-swing. This programming process utilizes both advance information (pitch history and count and optical information picked-up very early in the ball's flight (ball time to contact TTC and rotation direction. The pre-programmed value of MT is used to determine a critical value of TTC for swing initiation. Finally, because a baseball swing is an action that is occasionally interrupted online (i.e., a “check swing”, I will discuss experiments that examine when this pre-programmed action can be stopped and the sources of optical information that trigger stopping.

Using video and theater to increase knowledge and change attitudes-Why are gorillas important to the world and to Congo?

Science.gov (United States)

Breuer, Thomas; Mavinga, Franck Barrel; Evans, Ron; Lukas, Kristen E

2017-10-01

Applying environmental education in primate range countries is an important long-term activity to stimulate pro-conservation behavior. Within captive settings, mega-charismatic species, such as great apes are often used to increase knowledge and positively influence attitudes of visitors. Here, we evaluate the effectiveness of a short-term video and theater program developed for a Western audience and adapted to rural people living in two villages around Nouabalé-Ndoki National Park, Republic of Congo. We assessed the knowledge gain and attitude change using oral evaluation in the local language (N = 111). Overall pre-program knowledge about Western gorillas (Gorilla gorilla) was high. Detailed multivariate analysis of pre-program knowledge revealed differences in knowledge between two villages and people with different jobs while attitudes largely were similar between groups. The short-term education program was successful in raising knowledge, particularly of those people with less pre-program knowledge. We also noted an overall significant attitude improvement. Our data indicate short-term education programs are useful in quickly raising knowledge as well improving attitudes. Furthermore, education messages need to be clearly adapted to the daily livelihood realities of the audience, and multi-variate analysis can help to identify potential target groups for education programs. © 2017 Wiley Periodicals, Inc.

Anomaly Detection for Complex Systems

Data.gov (United States)

National Aeronautics and Space Administration — In performance maintenance in large, complex systems, sensor information from sub-components tends to be readily available, and can be used to make predictions about...

Modeling OPC complexity for design for manufacturability

Science.gov (United States)

Gupta, Puneet; Kahng, Andrew B.; Muddu, Swamy; Nakagawa, Sam; Park, Chul-Hong

2005-11-01

Increasing design complexity in sub-90nm designs results in increased mask complexity and cost. Resolution enhancement techniques (RET) such as assist feature addition, phase shifting (attenuated PSM) and aggressive optical proximity correction (OPC) help in preserving feature fidelity in silicon but increase mask complexity and cost. Data volume increase with rise in mask complexity is becoming prohibitive for manufacturing. Mask cost is determined by mask write time and mask inspection time, which are directly related to the complexity of features printed on the mask. Aggressive RET increase complexity by adding assist features and by modifying existing features. Passing design intent to OPC has been identified as a solution for reducing mask complexity and cost in several recent works. The goal of design-aware OPC is to relax OPC tolerances of layout features to minimize mask cost, without sacrificing parametric yield. To convey optimal OPC tolerances for manufacturing, design optimization should drive OPC tolerance optimization using models of mask cost for devices and wires. Design optimization should be aware of impact of OPC correction levels on mask cost and performance of the design. This work introduces mask cost characterization (MCC) that quantifies OPC complexity, measured in terms of fracture count of the mask, for different OPC tolerances. MCC with different OPC tolerances is a critical step in linking design and manufacturing. In this paper, we present a MCC methodology that provides models of fracture count of standard cells and wire patterns for use in design optimization. MCC cannot be performed by designers as they do not have access to foundry OPC recipes and RET tools. To build a fracture count model, we perform OPC and fracturing on a limited set of standard cells and wire configurations with all tolerance combinations. Separately, we identify the characteristics of the layout that impact fracture count. Based on the fracture count (FC) data

Simulation in Complex Modelling

DEFF Research Database (Denmark)

Nicholas, Paul; Ramsgaard Thomsen, Mette; Tamke, Martin

2017-01-01

This paper will discuss the role of simulation in extended architectural design modelling. As a framing paper, the aim is to present and discuss the role of integrated design simulation and feedback between design and simulation in a series of projects under the Complex Modelling framework. Complex...... performance, engage with high degrees of interdependency and allow the emergence of design agency and feedback between the multiple scales of architectural construction. This paper presents examples for integrated design simulation from a series of projects including Lace Wall, A Bridge Too Far and Inflated...... Restraint developed for the research exhibition Complex Modelling, Meldahls Smedie Gallery, Copenhagen in 2016. Where the direct project aims and outcomes have been reported elsewhere, the aim for this paper is to discuss overarching strategies for working with design integrated simulation....

Nonparametric Bayesian Modeling of Complex Networks

DEFF Research Database (Denmark)

Schmidt, Mikkel Nørgaard; Mørup, Morten

2013-01-01

an infinite mixture model as running example, we go through the steps of deriving the model as an infinite limit of a finite parametric model, inferring the model parameters by Markov chain Monte Carlo, and checking the model?s fit and predictive performance. We explain how advanced nonparametric models......Modeling structure in complex networks using Bayesian nonparametrics makes it possible to specify flexible model structures and infer the adequate model complexity from the observed data. This article provides a gentle introduction to nonparametric Bayesian modeling of complex networks: Using...

Show and Tell: Video Modeling and Instruction Without Feedback Improves Performance but Is Not Sufficient for Retention of a Complex Voice Motor Skill.

Science.gov (United States)

Look, Clarisse; McCabe, Patricia; Heard, Robert; Madill, Catherine J

2018-02-02

Modeling and instruction are frequent components of both traditional and technology-assisted voice therapy. This study investigated the value of video modeling and instruction in the early acquisition and short-term retention of a complex voice task without external feedback. Thirty participants were randomized to two conditions and trained to produce a vocal siren over 40 trials. One group received a model and verbal instructions, the other group received a model only. Sirens were analyzed for phonation time, vocal intensity, cepstral peak prominence, peak-to-peak time, and root-mean-square error at five time points. The model and instruction group showed significant improvement on more outcome measures than the model-only group. There was an interaction effect for vocal intensity, which showed that instructions facilitated greater improvement when they were first introduced. However, neither group reproduced the model's siren performance across all parameters or retained the skill 1 day later. Providing verbal instruction with a model appears more beneficial than providing a model only in the prepractice phase of acquiring a complex voice skill. Improved performance was observed; however, the higher level of performance was not retained after 40 trials in both conditions. Other prepractice variables may need to be considered. Findings have implications for traditional and technology-assisted voice therapy. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Lie and Noether symmetries of systems of complex ordinary ...

Indian Academy of Sciences (India)

2014-07-02

Jul 2, 2014 ... Abstract. The Lie and Noether point symmetry analyses of a kth-order system of m complex ordi- nary differential equations (ODEs) with m dependent variables are performed. The decomposition of complex symmetries of the given system of complex ODEs yields Lie- and Noether-like opera- tors.

The effects of sampling bias and model complexity on the predictive performance of MaxEnt species distribution models.

Science.gov (United States)

Syfert, Mindy M; Smith, Matthew J; Coomes, David A

2013-01-01

Species distribution models (SDMs) trained on presence-only data are frequently used in ecological research and conservation planning. However, users of SDM software are faced with a variety of options, and it is not always obvious how selecting one option over another will affect model performance. Working with MaxEnt software and with tree fern presence data from New Zealand, we assessed whether (a) choosing to correct for geographical sampling bias and (b) using complex environmental response curves have strong effects on goodness of fit. SDMs were trained on tree fern data, obtained from an online biodiversity data portal, with two sources that differed in size and geographical sampling bias: a small, widely-distributed set of herbarium specimens and a large, spatially clustered set of ecological survey records. We attempted to correct for geographical sampling bias by incorporating sampling bias grids in the SDMs, created from all georeferenced vascular plants in the datasets, and explored model complexity issues by fitting a wide variety of environmental response curves (known as "feature types" in MaxEnt). In each case, goodness of fit was assessed by comparing predicted range maps with tree fern presences and absences using an independent national dataset to validate the SDMs. We found that correcting for geographical sampling bias led to major improvements in goodness of fit, but did not entirely resolve the problem: predictions made with clustered ecological data were inferior to those made with the herbarium dataset, even after sampling bias correction. We also found that the choice of feature type had negligible effects on predictive performance, indicating that simple feature types may be sufficient once sampling bias is accounted for. Our study emphasizes the importance of reducing geographical sampling bias, where possible, in datasets used to train SDMs, and the effectiveness and essentialness of sampling bias correction within MaxEnt.

Functional Mitochondrial Complex I Is Required by Tobacco Leaves for Optimal Photosynthetic Performance in Photorespiratory Conditions and during Transients1

Science.gov (United States)

Dutilleul, Christelle; Driscoll, Simon; Cornic, Gabriel; De Paepe, Rosine; Foyer, Christine H.; Noctor, Graham

2003-01-01

The importance of the mitochondrial electron transport chain in photosynthesis was studied using the tobacco (Nicotiana sylvestris) mutant CMSII, which lacks functional complex I. Rubisco activities and oxygen evolution at saturating CO2 showed that photosynthetic capacity in the mutant was at least as high as in wild-type (WT) leaves. Despite this, steady-state photosynthesis in the mutant was reduced by 20% to 30% at atmospheric CO2 levels. The inhibition of photosynthesis was alleviated by high CO2 or low O2. The mutant showed a prolonged induction of photosynthesis, which was exacerbated in conditions favoring photorespiration and which was accompanied by increased extractable NADP-malate dehydrogenase activity. Feeding experiments with leaf discs demonstrated that CMSII had a lower capacity than the WT for glycine (Gly) oxidation in the dark. Analysis of the postillumination burst in CO2 evolution showed that this was not because of insufficient Gly decarboxylase capacity. Despite the lower rate of Gly metabolism in CMSII leaves in the dark, the Gly to Ser ratio in the light displayed a similar dependence on photosynthesis to the WT. It is concluded that: (a) Mitochondrial complex I is required for optimal photosynthetic performance, despite the operation of alternative dehydrogenases in CMSII; and (b) complex I is necessary to avoid redox disruption of photosynthesis in conditions where leaf mitochondria must oxidize both respiratory and photorespiratory substrates simultaneously. PMID:12529534

Complex Heat Exchangers for Improved Performance

Science.gov (United States)

Bran, Gabriela Alejandra

After a detailed literature review, it was determined that there was a need for a more comprehensive study on the transient behavior of heat exchangers. Computational power was not readily available when most of the work on transient heat exchangers was done (1956 - 1986), so most of these solutions have restrictions, or very specific assumptions. More recently, authors have obtained numerical solutions for more general problems (2003 - 2013), but they have investigated very specific conditions, and cases. For a more complex heat exchanger (i.e. with heat generation), the transient solutions from literature are no longer valid. There was a need to develop a numerical model that relaxes the restrictions of current solutions to explore conditions that have not been explored. A one dimensional transient heat exchanger model was developed. There are no restrictions on the fluids and wall conditions. The model is able to obtain a numerical solution for a wide range of fluid properties and mass flow rates. Another innovative characteristic of the numerical model is that the boundary and initial conditions are not limited to constant values. The boundary conditions can be a function of time (i.e. sinusoidal signal), and the initial conditions can be a function of position. Four different cases were explored in this work. In the first case, the start-up of a system was investigated where the whole system is assumed to be at the same temperature. In the second case, the new steady state in case one gets disrupted by a smaller inlet temperature step change. In the third case, the new steady state in case one gets disrupted by a step change in one of the mass flow rates. The response of these three cases show that there are different transient behaviors, and they depend on the conditions imposed on the system. The fourth case is a system that has a sinusoidal time varying inlet temperature for one of the flows. The results show that the sinusoidal behavior at the inlet

Considerations on the hyperbolic complex Klein-Gordon equation

International Nuclear Information System (INIS)

Ulrych, S.

2010-01-01

This article summarizes and consolidates investigations on hyperbolic complex numbers with respect to the Klein-Gordon equation for fermions and bosons. The hyperbolic complex numbers are applied in the sense that complex extensions of groups and algebras are performed not with the complex unit, but with the product of complex and hyperbolic unit. The modified complexification is the key ingredient for the theory. The Klein-Gordon equation is represented in this framework in the form of the first invariant of the Poincare group, the mass operator, in order to emphasize its geometric origin. The possibility of new interactions arising from hyperbolic complex gauge transformations is discussed.

Energetic lanthanide complexes: coordination chemistry and explosives applications

International Nuclear Information System (INIS)

Manner, V W; Barker, B J; Sanders, V E; Laintz, K E; Scott, B L; Preston, D N; Sandstrom, M; Reardon, B L

2014-01-01

Metals are generally added to organic molecular explosives in a heterogeneous composite to improve overall heat and energy release. In order to avoid creating a mixture that can vary in homogeneity, energetic organic molecules can be directly bonded to high molecular weight metals, forming a single metal complex with Angstrom-scale separation between the metal and the explosive. To probe the relationship between the structural properties of metal complexes and explosive performance, a new series of energetic lanthanide complexes has been prepared using energetic ligands such as NTO (5-nitro-2,4-dihydro-1,2,4-triazole-3-one). These are the first examples of lanthanide NTO complexes where no water is coordinated to the metal, demonstrating novel control of the coordination environment. The complexes have been characterized by X-ray crystallography, NMR and IR spectroscopies, photoluminescence, and sensitivity testing. The structural and energetic properties are discussed in the context of enhanced blast effects and detection. Cheetah calculations have been performed to fine-tune physical properties, creating a systematic method for producing explosives with 'tailor made' characteristics. These new complexes will be benchmarks for further study in the field of metalized high explosives.

On the Concept Image of Complex Numbers

Science.gov (United States)

Nordlander, Maria Cortas; Nordlander, Edvard

2012-01-01

A study of how Swedish students understand the concept of complex numbers was performed. A questionnaire was issued reflecting the student view of own perception. Obtained answers show a variety of concept images describing how students adopt the concept of complex numbers. These concept images are classified into four categories in order to…

Mining Important Nodes in Directed Weighted Complex Networks

Directory of Open Access Journals (Sweden)

Yunyun Yang

2017-01-01

Full Text Available In complex networks, mining important nodes has been a matter of concern by scholars. In recent years, scholars have focused on mining important nodes in undirected unweighted complex networks. But most of the methods are not applicable to directed weighted complex networks. Therefore, this paper proposes a Two-Way-PageRank method based on PageRank for further discussion of mining important nodes in directed weighted complex networks. We have mainly considered the frequency of contact between nodes and the length of time of contact between nodes. We have considered the source of the nodes (in-degree and the whereabouts of the nodes (out-degree simultaneously. We have given node important performance indicators. Through numerical examples, we analyze the impact of variation of some parameters on node important performance indicators. Finally, the paper has verified the accuracy and validity of the method through empirical network data.

On the interconnection of stable protein complexes: inter-complex hubs and their conservation in Saccharomyces cerevisiae and Homo sapiens networks.

Science.gov (United States)

Guerra, Concettina

2015-01-01

Protein complexes are key molecular entities that perform a variety of essential cellular functions. The connectivity of proteins within a complex has been widely investigated with both experimental and computational techniques. We developed a computational approach to identify and characterise proteins that play a role in interconnecting complexes. We computed a measure of inter-complex centrality, the crossroad index, based on disjoint paths connecting proteins in distinct complexes and identified inter-complex hubs as proteins with a high value of the crossroad index. We applied the approach to a set of stable complexes in Saccharomyces cerevisiae and in Homo sapiens. Just as done for hubs, we evaluated the topological and biological properties of inter-complex hubs addressing the following questions. Do inter-complex hubs tend to be evolutionary conserved? What is the relation between crossroad index and essentiality? We found a good correlation between inter-complex hubs and both evolutionary conservation and essentiality.

Molecular architecture of the yeast Mediator complex

Science.gov (United States)

Robinson, Philip J; Trnka, Michael J; Pellarin, Riccardo; Greenberg, Charles H; Bushnell, David A; Davis, Ralph; Burlingame, Alma L; Sali, Andrej; Kornberg, Roger D

2015-01-01

The 21-subunit Mediator complex transduces regulatory information from enhancers to promoters, and performs an essential role in the initiation of transcription in all eukaryotes. Structural information on two-thirds of the complex has been limited to coarse subunit mapping onto 2-D images from electron micrographs. We have performed chemical cross-linking and mass spectrometry, and combined the results with information from X-ray crystallography, homology modeling, and cryo-electron microscopy by an integrative modeling approach to determine a 3-D model of the entire Mediator complex. The approach is validated by the use of X-ray crystal structures as internal controls and by consistency with previous results from electron microscopy and yeast two-hybrid screens. The model shows the locations and orientations of all Mediator subunits, as well as subunit interfaces and some secondary structural elements. Segments of 20–40 amino acid residues are placed with an average precision of 20 Å. The model reveals roles of individual subunits in the organization of the complex. DOI: http://dx.doi.org/10.7554/eLife.08719.001 PMID:26402457

Corrosion protective performance of amino trimethylene phosphonic acid-metal complex layers fabricated on the cold-rolled steel substrate via one-step assembly

Science.gov (United States)

Yan, Ru; He, Wei; Zhai, Tianhua; Ma, Houyi

2018-06-01

Seeing that amino trimethylene phosphonic acid (ATMP) possesses very strong complexation ability to metal ions and the phosphonic acid group has good affinity for the oxidized iron surface, herein a simple and rapid film-forming method (one-step assembly method) was developed to construct the ATMP-Zn complex conversion layers (ATMP-Zn layers for short) on the cold-rolled steel (CRS) substrate. Zinc ions were found to participate in the formation process of ATMP-based composite film, which made the Zn-containing ATMP film significantly different in appearance, thickness, microstructure and film-forming mechanisms from the Zn-free ATMP film. There was mainly iron (ш) phosphonate in the Zn-free ATMP film, whereas there were Zn2+-ATMP complex and a certain amount of ZnO in the ATMP-Zn composite film. In addition, electrochemical test results clearly indicate that corrosion resistance of ATMP-Zn composite film was greatly enhanced due to the presence of Zn component. Moreover, the corrosion resistance performance could be controlled by adjusting film-forming time, pH and ATMP concentration in the film-forming solutions. The present study provides a new method for the design and fabrication of high-quality environmentally-friendly conversion layers.

Finding optimal interaction interface alignments between biological complexes

KAUST Repository

Cui, Xuefeng

2015-06-13

Motivation: Biological molecules perform their functions through interactions with other molecules. Structure alignment of interaction interfaces between biological complexes is an indispensable step in detecting their structural similarities, which are keys to understanding their evolutionary histories and functions. Although various structure alignment methods have been developed to successfully access the similarities of protein structures or certain types of interaction interfaces, existing alignment tools cannot directly align arbitrary types of interfaces formed by protein, DNA or RNA molecules. Specifically, they require a \\'blackbox preprocessing\\' to standardize interface types and chain identifiers. Yet their performance is limited and sometimes unsatisfactory. Results: Here we introduce a novel method, PROSTA-inter, that automatically determines and aligns interaction interfaces between two arbitrary types of complex structures. Our method uses sequentially remote fragments to search for the optimal superimposition. The optimal residue matching problem is then formulated as a maximum weighted bipartite matching problem to detect the optimal sequence order-independent alignment. Benchmark evaluation on all non-redundant protein-DNA complexes in PDB shows significant performance improvement of our method over TM-align and iAlign (with the \\'blackbox preprocessing\\'). Two case studies where our method discovers, for the first time, structural similarities between two pairs of functionally related protein-DNA complexes are presented. We further demonstrate the power of our method on detecting structural similarities between a protein-protein complex and a protein-RNA complex, which is biologically known as a protein-RNA mimicry case. © The Author 2015. Published by Oxford University Press.

Stability studies on 99mTechnetium(III) complexes with tridentate/monodentate thiol ligands and phosphine ('3+1+1' complexes)

International Nuclear Information System (INIS)

Seifert, Sepp; Drews, Antje; Gupta, Antje; Pietzsch, Hans-Juergen; Spies, Hartmut; Johannsen, Bernd

2000-01-01

The preparation and characterisation of 3+1+1 technetium complexes of the general formula [Tc(SES)(RS)(PMe 2 Ph)] (SES=tridentate dithiol ligand, E=S, O, NMe; RSH=monothiol ligand) at the n.c.a. level is described. The Tc(III) complexes are prepared in a one-step procedure starting from pertechnetate in yields of 85-95% of radiochemical purity. A comparison of their chromatographic data with the fully characterised 99 Tc complexes indicate the identity of the investigated compounds. Stability studies show that the 99m Tc complexes undergo some alteration in solution. They are oxidised to the 3+1 oxotechnetium (V) complexes and/or decompose in aqueous solution. In challenge experiments performed with glutathione, exchange of the monothiolato ligand occurs in the same manner as known for the 3+1 complexes

Terpyridine and Quaterpyridine Complexes as Sensitizers for Photovoltaic Applications

Directory of Open Access Journals (Sweden)

Davide Saccone

2016-02-01

Full Text Available Terpyridine and quaterpyridine-based complexes allow wide light harvesting of the solar spectrum. Terpyridines, with respect to bipyridines, allow for achieving metal-complexes with lower band gaps in the metal-to-ligand transition (MLCT, thus providing a better absorption at lower energy wavelengths resulting in an enhancement of the solar light-harvesting ability. Despite the wider absorption of the first tricarboxylate terpyridyl ligand-based complex, Black Dye (BD, dye-sensitized solar cell (DSC performances are lower if compared with N719 or other optimized bipyridine-based complexes. To further improve BD performances several modifications have been carried out in recent years affecting each component of the complexes: terpyridines have been replaced by quaterpyridines; other metals were used instead of ruthenium, and thiocyanates have been replaced by different pinchers in order to achieve cyclometalated or heteroleptic complexes. The review provides a summary on design strategies, main synthetic routes, optical and photovoltaic properties of terpyridine and quaterpyridine ligands applied to photovoltaic, and focuses on n-type DSCs.

Application of high performance liquid chromatography for the profiling of complex chemical mixtures with the aid of chemometrics.

Science.gov (United States)

Ni, Yongnian; Zhang, Liangsheng; Churchill, Jane; Kokot, Serge

2007-06-15

In this paper, chemometrics methods were applied to resolve the high performance liquid chromatography (HPLC) fingerprints of complex, many-component substances to compare samples from a batch from a given manufacturer, or from those of different producers. As an example of such complex substances, we used a common Chinese traditional medicine, Huoxiang Zhengqi Tincture (HZT) for this research. Twenty-one samples, each representing a separate HZT production batch from one of three manufacturers were analyzed by HPLC with the aid of a diode array detector (DAD). An Agilent Zorbax Eclipse XDB-C18 column with an Agilent Zorbax high pressure reliance cartridge guard-column were used. The mobile phase consisted of water (A) and methanol (B) with a gradient program of 25-65% (v/v, B) during 0-30min, 65-55% (v/v, B) during 30-35min and 55-100% (v/v, B) during 35-60min (flow rate, 1.0mlmin(-1); injection volume, 20mul; and column temperature-ambient). The detection wavelength was adjusted for maximum sensitivity at different time periods. A peak area matrix with 21objectsx14HPLC variables was obtained by sampling each chromatogram at 14 common retention times. Similarities were then calculated to discriminate the batch-to-batch samples and also, a more informative multi-criteria decision making methodology (MCDM), PROMETHEE and GAIA, was applied to obtain more information from the chromatograms in order to rank and compare the complex HZT profiles. The results showed that with the MCDM analysis, it was possible to match and discriminate correctly the batch samples from the three different manufacturers. Fourier transform infrared (FT-IR) spectra taken from samples from several batches were compared by the common similarity method with the HPLC results. It was found that the FT-IR spectra did not discriminate the samples from the different batches.

School Performance

Science.gov (United States)

Lamas, Héctor A.

2015-01-01

The school performance study of students is, due to its relevance and complexity, one of the issues of major controversy in the educational research, and it has been given special attention in the last decades. This study is intended to show a conceptual approach to the school performance construct, contextualizing the reality in the regular basic…

The impact of traffic noise on mental performance considering complexity of activities

Directory of Open Access Journals (Sweden)

I. Alimohammadi

2015-12-01

  Conclusion: One of the most significant findings emerged from this study is that traffic noise seems to have no effect on the mentioned variables under simple activity condition. However, traffic noise has devastating effects on median reaction time, number of appeared stimuli and reactions under complex activity condition.

Complex Decision Making Theory and Practice

CERN Document Server

Qudrat-Ullah, Hassan; Spector, J Michael

2007-01-01

The increasingly complex environment of today's world, characterized by technological innovation and global communication, generates myriads of possible and actual interactions while limited physical and intellectual resources severely impinge on decision makers, be it in the public or private domains. At the core of the decision-making process is the need for quality information that allows the decision maker to better assess the impact of decisions in terms of outcomes, nonlinear feedback processes and time delays on the performance of the complex system invoked. This volume is a timely review on the principles underlying complex decision making, the handling of uncertainties in dynamic envrionments and of the various modeling approaches used. The book consists of five parts, each composed of several chapters: I: Complex Decision Making: Concepts, Theories and Empirical Evidence II: Tools and Techniques for Decision Making in Complex Environments and Systems III: System Dynamics and Agent-Based Modeling IV:...

How and when Does Complex Reasoning Occur? Empirically Driven Development of a Learning Progression Focused on Complex Reasoning about Biodiversity

Science.gov (United States)

Songer, Nancy Butler; Kelcey, Ben; Gotwals, Amelia Wenk

2009-01-01

In order to compete in a global economy, students are going to need resources and curricula focusing on critical thinking and reasoning in science. Despite awareness for the need for complex reasoning, American students perform poorly relative to peers on international standardized tests measuring complex thinking in science. Research focusing on…

Bright electroluminescence from a chelate phosphine oxide Eu{sup III} complex with high thermal performance

Energy Technology Data Exchange (ETDEWEB)

Xu Hui [School of Chemistry and Materials, Heilongjiang University, 74 Xuefu Road, Nangang District, Harbin 150080, Heilongjiang Province (China); Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 66 Xinmofan Road, Nanjing 21003, Jiangsu Province (China); Yin Kun; Wang Lianhui [Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 66 Xinmofan Road, Nanjing 21003, Jiangsu Province (China); Huang Wei [Institute of Advanced Materials (IAM), Fudan University, 220 Handan Road, Shanghai 200433 (China)], E-mail: wei-huang@njupt.edu.cn

2008-10-01

The chelate phosphine oxide ligand 1,8-bis(diphenylphosphino)naphthalene oxide (NaPO) was used to prepare complex 1 tris(2-thenoyltrifluoroacetonate)(1,8-bis(diphenylphosphino)naphthalene oxide)europium(III). The rigid structure of NaPO makes 1 have more compact structure resulting in a temperature of glass transition as high as 147 deg. C, which is the highest in luminescent Eu{sup III} complexes, and a higher decomposition temperature of 349 deg. C. The improvement of carrier transfer ability of NaPO was proved by Gaussian simulation. The multi-layered electroluminescent device based on 1 had a low turn-on voltage of 6.0 V, the maximum brightness of 601 cd m{sup -2} at 21.5 V and 481.4 mA cm{sup -2}, and the excellent voltage-independent spectral stability. These properties demonstrated NaPO cannot only be favorable to form the rigid and compact complex structure, and increase the thermal and morphological stability of the complex, but also reduce the formation of the exciplex.

Robot Learning from Demonstration: A Task-level Planning Approach

Directory of Open Access Journals (Sweden)

Staffan Ekvall

2008-09-01

Full Text Available In this paper, we deal with the problem of learning by demonstration, task level learning and planning for robotic applications that involve object manipulation. Preprogramming robots for execution of complex domestic tasks such as setting a dinner table is of little use, since the same order of subtasks may not be conceivable in the run time due to the changed state of the world. In our approach, we aim to learn the goal of the task and use a task planner to reach the goal given different initial states of the world. For some tasks, there are underlying constraints that must be fulfille, and knowing just the final goal is not sufficient. We propose two techniques for constraint identification. In the first case, the teacher can directly instruct the system about the underlying constraints. In the second case, the constraints are identified by the robot itself based on multiple observations. The constraints are then considered in the planning phase, allowing the task to be executed without violating any of them. We evaluate our work on a real robot performing pick-and-place tasks.

Fingerprinting of complex mixtures with the use of high performance liquid chromatography, inductively coupled plasma atomic emission spectroscopy and chemometrics

International Nuclear Information System (INIS)

Ni Yongnian; Peng Yunyan; Kokot, Serge

2008-01-01

The molecular and metal profile fingerprints were obtained from a complex substance, Atractylis chinensis DC-a traditional Chinese medicine (TCM), with the use of the high performance liquid chromatography (HPLC) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) techniques. This substance was used in this work as an example of a complex biological material, which has found application as a TCM. Such TCM samples are traditionally processed by the Bran, Cut, Fried and Swill methods, and were collected from five provinces in China. The data matrices obtained from the two types of analysis produced two principal component biplots, which showed that the HPLC fingerprint data were discriminated on the basis of the methods for processing the raw TCM, while the metal analysis grouped according to the geographical origin. When the two data matrices were combined into a one two-way matrix, the resulting biplot showed a clear separation on the basis of the HPLC fingerprints. Importantly, within each different grouping the objects separated according to their geographical origin, and they ranked approximately in the same order in each group. This result suggested that by using such an approach, it is possible to derive improved characterisation of the complex TCM materials on the basis of the two kinds of analytical data. In addition, two supervised pattern recognition methods, K-nearest neighbors (KNNs) method, and linear discriminant analysis (LDA), were successfully applied to the individual data matrices-thus, supporting the PCA approach

The Role of Awareness for Complex Planning Task Performance: A Microgaming Study

Science.gov (United States)

Lukosch, Heide; Groen, Daan; Kurapati, Shalini; Klemke, Roland; Verbraeck, Alexander

2016-01-01

This study introduces the concept of microgames to support situated learning in order to foster situational awareness (SA) of planners in seaport container terminals. In today's complex working environments, it is often difficult to develop the required level of understanding of a given situation, described as situational awareness. A container…

Simultaneous determination of trace amounts of metals by high-performance liquid chromatography after preconcentration with adsorption on chlorotrifluoroethylene polymer as their hexamethylenedithiocarbamate complexes

International Nuclear Information System (INIS)

Shijo, Yoshio; Yoshida, Hideaki; Uehara, Nobuo; Kitamura, Teruo; Yoshimoto, Eiji.

1996-01-01

A method for the simultaneous determination of Bi, Cd, Cu, In, Ni and Pb by high-performance liquid chromatography is presented. These metals are preconcentrated on poly(chlorotrifluoroethylene) resin particles as their hexamethylenedithiocarbamate (HMDC) complexes, and eluted with dimethyl sulfoxide, followed by HPLC separation and determination using an ODS column. The conditions for the adsorption of metal-HMDC complexes, such as the pH, HMDC concentration, amount of the resin particles and elution times with dimethyl sulfoxide, are discussed. The resulting solution is suitable for injection into reversed-phase HPLC. The detection limits for the metals were found to be at sub μgl -1 levels. The application of this principle to the trace analysis of Bi, Cd, Cu, In, Ni and Pb in high-purity aluminum is demonstrated. (author)

Collectives and the design of complex systems

CERN Document Server

Wolpert, David

2004-01-01

Increasingly powerful computers are making possible distributed systems comprised of many adaptive and self-motivated computational agents. Such systems, when distinguished by system-level performance criteria, are known as "collectives." Collectives and the Design of Complex Systems lays the foundation for a science of collectives and describes how to design them for optimal performance. An introductory survey chapter is followed by descriptions of information-processing problems that can only be solved by the joint actions of large communities of computers, each running its own complex, decentralized machine-learning algorithm. Subsequent chapters analyze the dynamics and structures of collectives, as well as address economic, model-free, and control-theory approaches to designing complex systems. The work assumes a modest understanding of basic statistics and calculus. Topics and Features: Introduces the burgeoning science of collectives and its practical applications in a single useful volume Combines ap...

Three perspectives on complexity: entropy, compression, subsymmetry

Science.gov (United States)

Nagaraj, Nithin; Balasubramanian, Karthi

2017-12-01

There is no single universally accepted definition of `Complexity'. There are several perspectives on complexity and what constitutes complex behaviour or complex systems, as opposed to regular, predictable behaviour and simple systems. In this paper, we explore the following perspectives on complexity: effort-to-describe (Shannon entropy H, Lempel-Ziv complexity LZ), effort-to-compress (ETC complexity) and degree-of-order (Subsymmetry or SubSym). While Shannon entropy and LZ are very popular and widely used, ETC is relatively a new complexity measure. In this paper, we also propose a novel normalized complexity measure SubSym based on the existing idea of counting the number of subsymmetries or palindromes within a sequence. We compare the performance of these complexity measures on the following tasks: (A) characterizing complexity of short binary sequences of lengths 4 to 16, (B) distinguishing periodic and chaotic time series from 1D logistic map and 2D Hénon map, (C) analyzing the complexity of stochastic time series generated from 2-state Markov chains, and (D) distinguishing between tonic and irregular spiking patterns generated from the `Adaptive exponential integrate-and-fire' neuron model. Our study reveals that each perspective has its own advantages and uniqueness while also having an overlap with each other.

Measuring the Complexity of Urban Form and Design

OpenAIRE

Boeing, Geoff

2017-01-01

Complex systems have become a popular lens for conceptualizing cities, and complexity has substantial implications for urban performance and resilience. This paper develops a typology of methods and measures for assessing the complexity of the built form at the scale of urban design. It extends quantitative methods from urban planning, network science, ecosystems studies, fractal geometry, and information theory to the physical urban form and the analysis of qualitative human experience. Metr...

Performance objectives for the Hanford Immobilized Low-Activity Waste (ILAW) performance assessment

International Nuclear Information System (INIS)

MANN, F.M.

1999-01-01

Performance objectives for the disposal of low activity waste from Hanford Waste Tanks have been developed. These objectives have been based on DOE requirements, programmatic requirements, and public involvement. The DOE requirements include regulations that direct the performance assessment and are cited within the Radioactive Waste Management Order (DOE Order 435.1). Performance objectives for other DOE complex performance assessments have been included

Estimates of Fermilab Tevatron collider performance

International Nuclear Information System (INIS)

Dugan, G.

1991-09-01

This paper describes a model which has been used to estimate the average luminosity performance of the Tevatron collider. In the model, the average luminosity is related quantitatively to various performance parameters of the Fermilab Tevatron collider complex. The model is useful in allowing estimates to be developed for the improvements in average collider luminosity to be expected from changes in the fundamental performance parameters as a result of upgrades to various parts of the accelerator complex

Information Distribution in Complex Systems to Improve Team Performance

National Research Council Canada - National Science Library

Sperling, Brian K; Pritchett, Amy; Estrada, Arthur; Adam, Gina E

2006-01-01

.... Specifically, this study hypothesizes that providing task specific information to individual team members will improve coordination and decision-making, and therefore team performance, at time-critical tasks...

Complex anal fistulas: plug or flap?

Science.gov (United States)

Muhlmann, Mark D; Hayes, Julian L; Merrie, Arend E H; Parry, Bryan R; Bissett, Ian P

2011-10-01

Rectal mucosal advancement flaps (RMAF) and fistula plugs (FP) are techniques used to manage complex anal fistulas. The purpose of this study was to review and compare the results of these methods of repair. A retrospective review of all complex anal fistulas treated by either a RMAF or a FP at Auckland City Hospital from 2004 to 2008. Comparisons were made in terms of successful healing rates, time to failure and the use of magnetic resonance imaging. Overall, 70 operations were performed on 55 patients (55.7% male). The mean age was 44.9 years. Twenty-one patients (30%) had had at least one previous unsuccessful repair. Indications for repair included 57 high cryptoglandular anal (81%), 4 Crohn's anal (6%), 7 rectovaginal (10%), 1 rectourethral (1%) and 1 pouch-vaginal fistula (1%). All patients were followed up with a mean of 4.5 months. Forty-eight RMAFs (69% of total) were performed with 16 successful repairs (33%). Twenty-two FPs (31% of total) were performed with 7 successful repairs (32%, P = 0.9). In failed repairs, there was no difference in terms of mean time to failure (RMAF 4.8 months versus FP 4.1 months, P = 0.62). Magnetic resonance imaging was performed in 21 patients (37%) before the repair. The success rate in these patients was 20%. The results of treatment of complex anal fistulas are disappointing. The choice of operation of either a RMAF or a FP did not alter the poor healing rates of about one third of patients in each group.

Task Complexity, Student Perceptions of Vocabulary Learning in EFL, and Task Performance

Science.gov (United States)

Wu, Xiaoli; Lowyck, Joost; Sercu, Lies; Elen, Jan

2013-01-01

Background: The study deepened our understanding of how students' self-ef?cacy beliefs contribute to the context of teaching English as a foreign language in the framework of cognitive mediational paradigm at a ?ne-tuned task-speci?c level. Aim: The aim was to examine the relationship among task complexity, self-ef?cacy beliefs, domain-related…

Acute social stress before the planning phase improves memory performance in a complex real life-related prospective memory task.

Science.gov (United States)

Glienke, Katharina; Piefke, Martina

2016-09-01

Successful execution of intentions, but also the failure to recall are common phenomena in everyday life. The planning, retention, and realization of intentions are often framed as the scientific concept of prospective memory. The current study aimed to examine the influence of acute stress on key dimensions of complex "real life" prospective memory. To this end, we applied a prospective memory task that involved the planning, retention, and performance of intentions during a fictional holiday week. Forty healthy males participated in the study. Half of the subjects were stressed with the Socially Evaluated Cold Pressor Test (SECPT) before the planning of intentions, and the other half of the participants underwent a control procedure at the same time. Salivary cortisol was used to measure the effectiveness of the SECPT stress induction. Stressed participants did not differ from controls in planning accuracy. However, when we compared stressed participants with controls during prospective memory retrieval, we found statistically significant differences in PM across the performance phase. Participants treated with the SECPT procedure before the planning phase showed improved prospective memory retrieval over time, while performance of controls declined. Particularly, there was a significant difference between the stress and control group for the last two days of the holiday week. Interestingly, control participants showed significantly better performance for early than later learned items, which could be an indicator of a primacy effect. This differential effect of stress on performance was also found in time- and event-dependent prospective memory. Our results demonstrate for the first time, that acute stress induced before the planning phase may improve prospective memory over the time course of the performance phase in time- and event-dependent prospective memory. Our data thus indicate that prospective memory can be enhanced by acute stress. Copyright © 2016

Division in a Binary Representation for Complex Numbers

Science.gov (United States)

Blest, David C.; Jamil, Tariq

2003-01-01

Computer operations involving complex numbers, essential in such applications as Fourier transforms or image processing, are normally performed in a "divide-and-conquer" approach dealing separately with real and imaginary parts. A number of proposals have treated complex numbers as a single unit but all have foundered on the problem of the…

Abstract

African Journals Online (AJOL)

PROF. O. E. OSUAGWU

An Authoring system is a software with pre-programmed elements which allows both programmers ... doing things in all aspects of human endeavour. ... learning is offered through an Internet .... based or problem-based learning environment.

Feasible quantum communication complexity protocol

International Nuclear Information System (INIS)

Galvao, Ernesto F.

2002-01-01

I show that a simple multiparty communication task can be performed more efficiently with quantum communication than with classical communication, even with low detection efficiency η. The task is a communication complexity problem in which distant parties need to compute a function of the distributed inputs, while minimizing the amount of communication between them. A realistic quantum optical setup is suggested that can demonstrate a five-party quantum protocol with higher-than-classical performance, provided η>0.33

Effect of squatting on sprinting performance and repeated exposure to complex training in male rugby players.

Science.gov (United States)

Comyns, Thomas M; Harrison, Andrew J; Hennessy, Liam K

2010-03-01

This study was undertaken to examine the effect of a heavy weight training exercise on sprinting performance and on the effect of repeated exposure to a complex training protocol. Eleven male rugby union players (age 20.9 +/- 3.1 years) participated in the study, which involved 5 separate testing sessions. Back squat 3 repetition maximum (3RM) was established in session 1. Sessions 2-5 were identical and involved the subjects completing a 30-m sprint before and after a 3RM back squat protocol. Four minutes of rest was given between the back squatting and the posttest 30-m sprint. All sprint trials were measured with a laser measurement device (LAVEG, Jenoptik, Jena, Germany). Sprint time and instantaneous, average, and maximum velocity were the dependent variables. The criterion for significance was set at an alpha level of p > or = 0.05. No significant improvement was evident for any of the testing sessions (p > or = 0.05). In session 1, there was a significant increase in 30-m time and a significant reduction in average 30-m velocity and maximum velocity (p benefits in sprinting may not have been realized because of intra and intersubject variations in sprint technique. The session x phase interaction revealed a significant improvement in the pre to posttest changes in instantaneous velocity at 20 m (p = 0.035) and 30 m (p = 0.036) from session 1 to session 4. This indicates that the rugby players may be able to learn to apply the potentiation effects of complex training. From a practical perspective, players may need repeated exposure to this training modality to gain benefit from it, and this should be reflected in program planning.

FPGA implementation of low complexity LDPC iterative decoder

Science.gov (United States)

Verma, Shivani; Sharma, Sanjay

2016-07-01

Low-density parity-check (LDPC) codes, proposed by Gallager, emerged as a class of codes which can yield very good performance on the additive white Gaussian noise channel as well as on the binary symmetric channel. LDPC codes have gained lots of importance due to their capacity achieving property and excellent performance in the noisy channel. Belief propagation (BP) algorithm and its approximations, most notably min-sum, are popular iterative decoding algorithms used for LDPC and turbo codes. The trade-off between the hardware complexity and the decoding throughput is a critical factor in the implementation of the practical decoder. This article presents introduction to LDPC codes and its various decoding algorithms followed by realisation of LDPC decoder by using simplified message passing algorithm and partially parallel decoder architecture. Simplified message passing algorithm has been proposed for trade-off between low decoding complexity and decoder performance. It greatly reduces the routing and check node complexity of the decoder. Partially parallel decoder architecture possesses high speed and reduced complexity. The improved design of the decoder possesses a maximum symbol throughput of 92.95 Mbps and a maximum of 18 decoding iterations. The article presents implementation of 9216 bits, rate-1/2, (3, 6) LDPC decoder on Xilinx XC3D3400A device from Spartan-3A DSP family.

MYCOBACTERIUM COMPLEX IDENTIFICATION BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Directory of Open Access Journals (Sweden)

S.A HAWAII

2001-12-01

Full Text Available Introduction: There are different ways for identification of Mycobacteria. One of the most sensitive method is HPLC of phenacyl esters of mycolic acids of Mycobacteria for rapid identification of them after their primary cultures. This study uses HPLC for rapid identification and dissociation of Mycobacterium tuberculosis complex. Methods: In this study we use HPLC patterns of mycolic acids for identification three important species of mycobacteria (M. tuberculosis, M. bovis, M. bovis BCG from other mycobacterial species. All the strains were obtained from Tuberculosis and Pulmonary Diseases Research Center. HPLC conditions was as follows: HPLC: Model 1200 Cecil, Column: URP C-18 25X4.6 mm, Detector: U.V variable wave length at 254 nm, Elution: Gradient of methanol/chloroform. Flow rate: 2.5 ml/min. Results: HPLC leads to obtaining chromatograms which on its X-axis retention times (of different peaks which exist in the sample and on its Y-axis U.V absorbance (of these peaks were drown. These chromatograms in M. bovis and M. tuberculosis samples are similar with each other but differs from BCG ones. Discussion: On the basis of different retention times and numbers of the peaks which present in each chromatogram, we can differentiate between M. bovis, M. tuberculosis and BCG from other Mycobacteria. Also, with this method we can identify BCG from M. bovis and M. tuberculosis (because BCG has 9 and M. bovis and M. tuberculosis has 7 characteristic peaks in their chromatograms.

Low-Complexity Combining Schemes in Dual-Hop AF Relaying Systems

KAUST Repository

Gaaloul, Fakhreddine

2011-07-18

This paper investigates the performance of different low-complexity combining schemes in the context of dual-hop amplify-and-forward (AF) relaying networks. It is assumed that the relay uses single transmit (receive) antenna due to space limitation and to reduce the processing complexity. On the other hand, the transmitter and the receiver use antenna arrays to improve the overall diversity gain. However, this gain is achieved at the expense of increased processing complexity and power consumption. To this end, some combining schemes aiming at reducing the processing complexity and decreasing the number of active receive channels are investigated. Through the analysis, new formulas for the end-to-end signal-to-noise ratio (SNR) statistics in slowly varying and frequency flat Rayleigh fading channels are derived, which are then used to present some performance measures. Numerical and simulation results are presented to clarify the trade-off between the achieved diversity gain and the receive processing complexity. © 2011 IEEE.

Electrolytic conductivity of synthetic organomineral complexes

Directory of Open Access Journals (Sweden)

Ksiezopolska Alicja

2005-01-01

Full Text Available The mechanism of the formation of organomineral complexes in soils is very complex and still little known. Examination of the complexes in unaltered form, as isolated from the soil, is very difficult due to the dispersing effect of all extraction agents which break the complexes up, destroying their natural properties. It is much easier to perform most of the tests on preparations of organomineral complexes obtained under laboratory conditions. This paper is concerned with model research on the formation of synthetic complexes of humic acids with minerals: Na-montmorillonite, mica, kaolinite at various pH values (3-7 and in the presence of aluminum ions. The aim of the research was to develop an optimum reaction of suspension for the synthesis of organomineral complexes, to study the role of aluminum ions, and to attempt to determine the degree of their complexity on the basis of the electrolytic conductivity (EC. An important influence of the suspension pH value on the value of EC was observed. The greatest correlation was found in the organomineral preparations with kaolinite and with aluminum (r = 0.93***. Generally, it can be stated that the degree of reaction of humic acids with minerals depended most of all on the type of mineral, on the pH value, and on the presence of aluminum.

Organic Donor-Acceptor Complexes as Novel Organic Semiconductors.

Science.gov (United States)

Zhang, Jing; Xu, Wei; Sheng, Peng; Zhao, Guangyao; Zhu, Daoben

2017-07-18

Organic donor-acceptor (DA) complexes have attracted wide attention in recent decades, resulting in the rapid development of organic binary system electronics. The design and synthesis of organic DA complexes with a variety of component structures have mainly focused on metallicity (or even superconductivity), emission, or ferroelectricity studies. Further efforts have been made in high-performance electronic investigations. The chemical versatility of organic semiconductors provides DA complexes with a great number of possibilities for semiconducting applications. Organic DA complexes extend the semiconductor family and promote charge separation and transport in organic field-effect transistors (OFETs) and organic photovoltaics (OPVs). In OFETs, the organic complex serves as an active layer across extraordinary charge pathways, ensuring the efficient transport of induced charges. Although an increasing number of organic semiconductors have been reported to exhibit good p- or n-type properties (mobilities higher than 1 or even 10 cm 2 V -1 s -1 ), critical scientific challenges remain in utilizing the advantages of existing semiconductor materials for more and wider applications while maintaining less complicated synthetic or device fabrication processes. DA complex materials have revealed new insight: their unique molecular packing and structure-property relationships. The combination of donors and acceptors could offer practical advantages compared with their unimolecular materials. First, growing crystals of DA complexes with densely packed structures will reduce impurities and traps from the self-assembly process. Second, complexes based on the original structural components could form superior mixture stacking, which can facilitate charge transport depending on the driving force in the coassembly process. Third, the effective use of organic semiconductors can lead to tunable band structures, allowing the operation mode (p- or n-type) of the transistor to be

Detection of prostate cancer with complexed PSA and complexed/total PSA ratio - is there any advantage?

OpenAIRE

Strittmatter, F; Stieber, P; Nagel, D; Füllhase, C; Walther, S; Stief, CG; Waidelich, R

2011-01-01

Abstract Objective To evaluate the performance of total PSA (tPSA), the free/total PSA ratio (f/tPSA), complexed PSA (cPSA) and the complexed/total PSA ratio (c/tPSA) in prostate cancer detection. Methods Frozen sera of 442 patients have been analysed for tPSA, free PSA (fPSA) and cPSA. 131 patients had prostate cancer and 311 patients benign prostatic hyperplasia. Results Differences in the distribution of the biomarkers were seen as follows: tPSA, cPSA and c/tPSA were significantly higher i...

Investigation of anticancer properties of caffeinated complexes via computational chemistry methods

Science.gov (United States)

Sayin, Koray; Üngördü, Ayhan

2018-03-01

Computational investigations were performed for 1,3,7-trimethylpurine-2,6-dione, 3,7-dimethylpurine-2,6-dione, their Ru(II) and Os(III) complexes. B3LYP/6-311 ++G(d,p)(LANL2DZ) level was used in numerical calculations. Geometric parameters, IR spectrum, 1H-, 13C and 15N NMR spectrum were examined in detail. Additionally, contour diagram of frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP) maps, MEP contour and some quantum chemical descriptors were used in the determination of reactivity rankings and active sites. The electron density on the surface was similar to each other in studied complexes. Quantum chemical descriptors were investigated and the anticancer activity of complexes were more than cisplatin and their ligands. Additionally, molecular docking calculations were performed in water between related complexes and a protein (ID: 3WZE). The most interact complex was found as Os complex. The interaction energy was calculated as 342.9 kJ/mol.

Performance Assessment/Composite Analysis Modeling to Support a Holistic Strategy for the Closure of F Area, a Large Nuclear Complex at the Savannah River Site

International Nuclear Information System (INIS)

COOK, JAMES

2004-01-01

A performance-based approach is being used at the Savannah River Site to close the F area Complex. F Area consists of a number of large industrial facilities including plutonium separations, uranium fuel fabrication, tanks for storing high level waste and a number of smaller operations. A major part of the overall closure strategy is the use of techniques derived from the Performance Assessment and Composite Analysis requirements for low level waste disposal at DOE sites. This process will provide a means of demonstrating the basis for deactivation, decommissioning and closure decisions to management, stakeholders and regulators

Defining and Assessing Chinese Syntactic Complexity via TC-Units

Science.gov (United States)

Yu, Qiaona

2016-01-01

The triad dimensions of complexity, accuracy, and fluency (CAF) has been widely used for assessing second language performance and development. Unlike accuracy and fluency, the construct of Chinese syntactic complexity has not been comprehensibly conceptualized or operationalized. Moreover, not tailored to the typological differences such as the…

Simulating complex noise barrier reflections

NARCIS (Netherlands)

Eerden, F.J.M. van der; Lutgendorf, D.; Roo, F. de

2011-01-01

Within the EU FP7 QUIESST project, QUIeting the Environment for a Sustainable Surface Transport, a test method is being developed for the reflectivity of noise barriers. The method needs to account for a complex shape of barriers and the use of various types of absorbing materials. The performance

The complexes of Ho with methylenediphosphonate and 1 hydroxyethylidenephosphonate

International Nuclear Information System (INIS)

Vanura, P.; Jedinakova-Krizova, V.; Hakenova, L.; Munesawa, Y.

1999-01-01

The composition and stability of holmium methylenediphosphonate (MDP) and 1-hydroxyethylidenephosphonate (HEDP) complexes in the aqueous solution of 0.1 M NaCl at the temperature of 25 grad C were studied by potentiometric titration methods. The complexes of the composition HoH n L have been found in the aqueous solution if the concentration of the ligand is higher than the concentration of holmium. The protonation constants of both acids and stability constants of all complexes were determined and the comparison with literature data of analogical complexes of other lanthanides was performed. (authors)

Performance of the new automated Abbott RealTime MTB assay for rapid detection of Mycobacterium tuberculosis complex in respiratory specimens.

Science.gov (United States)

Chen, J H K; She, K K K; Kwong, T-C; Wong, O-Y; Siu, G K H; Leung, C-C; Chang, K-C; Tam, C-M; Ho, P-L; Cheng, V C C; Yuen, K-Y; Yam, W-C

2015-09-01

The automated high-throughput Abbott RealTime MTB real-time PCR assay has been recently launched for Mycobacterium tuberculosis complex (MTBC) clinical diagnosis. This study would like to evaluate its performance. We first compared its diagnostic performance with the Roche Cobas TaqMan MTB assay on 214 clinical respiratory specimens. Prospective analysis of a total 520 specimens was then performed to further evaluate the Abbott assay. The Abbott assay showed a lower limit of detection at 22.5 AFB/ml, which was more sensitive than the Cobas assay (167.5 AFB/ml). The two assays demonstrated a significant difference in diagnostic performance (McNemar's test; P = 0.0034), in which the Abbott assay presented significantly higher area under curve (AUC) than the Cobas assay (1.000 vs 0.880; P = 0.0002). The Abbott assay demonstrated extremely low PCR inhibition on clinical respiratory specimens. The automated Abbott assay required only very short manual handling time (0.5 h), which could help to improve the laboratory management. In the prospective analysis, the overall estimates for sensitivity and specificity of the Abbott assay were both 100 % among smear-positive specimens, whereas the smear-negative specimens were 96.7 and 96.1 %, respectively. No cross-reactivity with non-tuberculosis mycobacterial species was observed. The superiority in sensitivity of the Abbott assay for detecting MTBC in smear-negative specimens could further minimize the risk in MTBC false-negative detection. The new Abbott RealTime MTB assay has good diagnostic performance which can be a useful diagnostic tool for rapid MTBC detection in clinical laboratories.

Prediction of Biomolecular Complexes

KAUST Repository

Vangone, Anna; Oliva, Romina; Cavallo, Luigi; Bonvin, Alexandre M. J. J.

2017-01-01

Almost all processes in living organisms occur through specific interactions between biomolecules. Any dysfunction of those interactions can lead to pathological events. Understanding such interactions is therefore a crucial step in the investigation of biological systems and a starting point for drug design. In recent years, experimental studies have been devoted to unravel the principles of biomolecular interactions; however, due to experimental difficulties in solving the three-dimensional (3D) structure of biomolecular complexes, the number of available, high-resolution experimental 3D structures does not fulfill the current needs. Therefore, complementary computational approaches to model such interactions are necessary to assist experimentalists since a full understanding of how biomolecules interact (and consequently how they perform their function) only comes from 3D structures which provide crucial atomic details about binding and recognition processes. In this chapter we review approaches to predict biomolecular complexesBiomolecular complexes, introducing the concept of molecular dockingDocking, a technique which uses a combination of geometric, steric and energetics considerations to predict the 3D structure of a biological complex starting from the individual structures of its constituent parts. We provide a mini-guide about docking concepts, its potential and challenges, along with post-docking analysis and a list of related software.

Prediction of Biomolecular Complexes

KAUST Repository

Vangone, Anna

2017-04-12

Almost all processes in living organisms occur through specific interactions between biomolecules. Any dysfunction of those interactions can lead to pathological events. Understanding such interactions is therefore a crucial step in the investigation of biological systems and a starting point for drug design. In recent years, experimental studies have been devoted to unravel the principles of biomolecular interactions; however, due to experimental difficulties in solving the three-dimensional (3D) structure of biomolecular complexes, the number of available, high-resolution experimental 3D structures does not fulfill the current needs. Therefore, complementary computational approaches to model such interactions are necessary to assist experimentalists since a full understanding of how biomolecules interact (and consequently how they perform their function) only comes from 3D structures which provide crucial atomic details about binding and recognition processes. In this chapter we review approaches to predict biomolecular complexesBiomolecular complexes, introducing the concept of molecular dockingDocking, a technique which uses a combination of geometric, steric and energetics considerations to predict the 3D structure of a biological complex starting from the individual structures of its constituent parts. We provide a mini-guide about docking concepts, its potential and challenges, along with post-docking analysis and a list of related software.

Ferric and cobaltous hydroacid complexes for forward osmosis (FO) processes

KAUST Repository

Ge, Qingchun; Fu, Fengjiang; Chung, Neal Tai-Shung

2014-01-01

Cupric and ferric hydroacid complexes have proven their advantages as draw solutes in forward osmosis in terms of high water fluxes, negligible reverse solute fluxes and easy recovery (Ge and Chung, 2013. Hydroacid complexes: A new class of draw solutes to promote forward osmosis (FO) processes. Chemical Communications 49, 8471-8473.). In this study, cobaltous hydroacid complexes were explored as draw solutes and compared with the ferric hydroacid complex to study the factors influencing their FO performance. The solutions of the cobaltous complexes produce high osmotic pressures due to the presence of abundant hydrophilic groups. These solutes are able to dissociate and form a multi-charged anion and Na+ cations in water. In addition, these complexes have expanded structures which lead to negligible reverse solute fluxes and provide relatively easy approaches in regeneration. These characteristics make the newly synthesized cobaltous complexes appropriate as draw solutes. The FO performance of the cobaltous and ferric-citric acid (Fe-CA) complexes were evaluated respectively through cellulose acetate membranes, thin-film composite membranes fabricated on polyethersulfone supports (referred as TFC-PES), and polybenzimidazole and PES dual-layer (referred as PBI/PES) hollow fiber membranes. Under the conditions of DI water as the feed and facing the support layer of TFC-PES FO membranes (PRO mode), draw solutions at 2.0M produced relatively high water fluxes of 39-48 LMH (Lm-2hr-1) with negligible reverse solute fluxes. A water flux of 17.4 LMH was achieved when model seawater of 3.5wt.% NaCl replaced DI water as the feed and 2.0M Fe-CA as the draw solution under the same conditions. The performance of these hydroacid complexes surpasses those of the synthetic draw solutes developed in recent years. This observation, along with the relatively easy regeneration, makes these complexes very promising as a novel class of draw solutes. © 2014 Elsevier Ltd.

Ferric and cobaltous hydroacid complexes for forward osmosis (FO) processes

KAUST Repository

Ge, Qingchun

2014-07-01

Cupric and ferric hydroacid complexes have proven their advantages as draw solutes in forward osmosis in terms of high water fluxes, negligible reverse solute fluxes and easy recovery (Ge and Chung, 2013. Hydroacid complexes: A new class of draw solutes to promote forward osmosis (FO) processes. Chemical Communications 49, 8471-8473.). In this study, cobaltous hydroacid complexes were explored as draw solutes and compared with the ferric hydroacid complex to study the factors influencing their FO performance. The solutions of the cobaltous complexes produce high osmotic pressures due to the presence of abundant hydrophilic groups. These solutes are able to dissociate and form a multi-charged anion and Na+ cations in water. In addition, these complexes have expanded structures which lead to negligible reverse solute fluxes and provide relatively easy approaches in regeneration. These characteristics make the newly synthesized cobaltous complexes appropriate as draw solutes. The FO performance of the cobaltous and ferric-citric acid (Fe-CA) complexes were evaluated respectively through cellulose acetate membranes, thin-film composite membranes fabricated on polyethersulfone supports (referred as TFC-PES), and polybenzimidazole and PES dual-layer (referred as PBI/PES) hollow fiber membranes. Under the conditions of DI water as the feed and facing the support layer of TFC-PES FO membranes (PRO mode), draw solutions at 2.0M produced relatively high water fluxes of 39-48 LMH (Lm-2hr-1) with negligible reverse solute fluxes. A water flux of 17.4 LMH was achieved when model seawater of 3.5wt.% NaCl replaced DI water as the feed and 2.0M Fe-CA as the draw solution under the same conditions. The performance of these hydroacid complexes surpasses those of the synthetic draw solutes developed in recent years. This observation, along with the relatively easy regeneration, makes these complexes very promising as a novel class of draw solutes. © 2014 Elsevier Ltd.

Self-Assembly of Hierarchical DNA Nanotube Architectures with Well-Defined Geometries.

Science.gov (United States)

Jorgenson, Tyler D; Mohammed, Abdul M; Agrawal, Deepak K; Schulman, Rebecca

2017-02-28

An essential motif for the assembly of biological materials such as actin at the scale of hundreds of nanometers and beyond is a network of one-dimensional fibers with well-defined geometry. Here, we demonstrate the programmed organization of DNA filaments into micron-scale architectures where component filaments are oriented at preprogrammed angles. We assemble L-, T-, and Y-shaped DNA origami junctions that nucleate two or three micron length DNA nanotubes at high yields. The angles between the nanotubes mirror the angles between the templates on the junctions, demonstrating that nanoscale structures can control precisely how micron-scale architectures form. The ability to precisely program filament orientation could allow the assembly of complex filament architectures in two and three dimensions, including circuit structures, bundles, and extended materials.

4D printing of polymeric materials for tissue and organ regeneration.

Science.gov (United States)

Miao, Shida; Castro, Nathan; Nowicki, Margaret; Xia, Lang; Cui, Haitao; Zhou, Xuan; Zhu, Wei; Lee, Se-Jun; Sarkar, Kausik; Vozzi, Giovanni; Tabata, Yasuhiko; Fisher, John; Zhang, Lijie Grace

2017-12-01

Four dimensional (4D) printing is an emerging technology with great capacity for fabricating complex, stimuli-responsive 3D structures, providing great potential for tissue and organ engineering applications. Although the 4D concept was first highlighted in 2013, extensive research has rapidly developed, along with more-in-depth understanding and assertions regarding the definition of 4D. In this review, we begin by establishing the criteria of 4D printing, followed by an extensive summary of state-of-the-art technological advances in the field. Both transformation-preprogrammed 4D printing and 4D printing of shape memory polymers are intensively surveyed. Afterwards we will explore and discuss the applications of 4D printing in tissue and organ regeneration, such as developing synthetic tissues and implantable scaffolds, as well as future perspectives and conclusions.

Development evolving:The origins and meanings of instinct

Science.gov (United States)

Blumberg, Mark S.

2015-01-01

How do migratory birds, herding dogs, and navigating sea turtles do the amazing things that they do? For hundreds of years, scientists and philosophers have struggled over possible explanations. In time, one word came to dominate the discussion: instinct. It became the catch-all explanation for those adaptive and complex abilities that do not obviously result from learning or experience. Today, various animals are said to possess a survival instinct, migratory instinct, herding instinct, maternal instinct, or language instinct. But a closer look reveals that these and other “instincts” are not satisfactorily described as inborn, pre-programmed, hardwired, or genetically determined. Rather, research in this area teaches us that species-typical behaviors develop—and they do so in every individual under the guidance of species-typical experiences occurring within reliable ecological contexts. PMID:27906515

SABRE: a computer-based system for the assessment of body radioactivity by photon spectrometry. Part 4

International Nuclear Information System (INIS)

Venn, J.B.

1982-02-01

A PDP-11/10 computer system is described for the acquisition and processing of pulse height spectra from detectors used for the measurement of body radioactivity. Version 4 of SABRE (System for the Assessment of Body Radioactivity) provides control of multiple detection systems from visual display consoles by means of a command language. A wide range of facilities is available for the display, processing and storage of acquired spectra and complex operations may be pre-programmed by means of the SABRE MACRO language. The hardware includes a CAMAC interface to the detection systems, disc cartridge drives for mass storage of data and programs, and data-links to other computers. The software is written in assembler language and includes special features for the dynamic allocation of computer memory and for safeguarding acquired data. (author)

A computer-based spectrometry system for assessment of body radioactivity

International Nuclear Information System (INIS)

Venn, J.B.

1985-01-01

This paper describes a PDP-11 computer system operating under RT-11 for the acquisition and processing of pulse height spectra in the measurement of body radioactivity. SABRA (system for the assessment of body radioactivity) provides control of multiple detection systems from visual display consoles by means of a command language. A wide range of facilities is available for the display, processing and storage of acquired spectra and complex operations may be pre-programmed by means of the SABRE MACRO language. The hardware includes a CAMAC interface to the detection systems, disc cartridge drives for mass storage of data and programs, and data-links to other computers. The software is written in assembler language and includes special features for the dynamic allocation of computer memory and for safeguarding acquired data. (orig.)

Determinants of alliance portfolio complexity and its effect on innovative performance of companies

NARCIS (Netherlands)

Duijsters, G.M.; Lokshin, B.

2011-01-01

Alliance formation is often described as a mechanism used by firms to increase voluntary knowledge transfers. Access to external knowledge has been increasingly recognized as a main source of a firm's innovativeness. A phenomenon that has recently emerged is alliance portfolio complexity. In line

Can Different Complex Training Improve the Individual Phenomenon of Post-Activation Potentiation?

Science.gov (United States)

Chen, Zong-Rong; Lo, Shin-Liang; Wang, Min-Hsien; Yu, Ching-Fang; Peng, Hsien-Te

2017-02-01

The aims of the present study were (a) to determine whether the two types of complex training and vibration complex training would improve the individual phenomenon of post-activation potentiation (PAP) for every athlete in a team setting; and (b) to compare the acute effect of resistance and plyometric exercise, whole body vibration, complex training and vibration complex training on vertical jump performance. The participants were ten male division I college volleyball and basketball players. They were asked to perform three vertical jumps as a pre-test and were then randomly assigned to one of five PAP protocols, resistance exercise using half squat exercise, plyometric exercise using drop jumps with individualized drop height, whole body vibration using squats on a vibration plate, complex training combining resistance exercise with plyometric exercise, vibration complex training combining whole body vibration with plyometric exercise. Three vertical jumps were performed four minutes after the PAP protocol as a post-test. A two-way repeated-measures analysis of variance was used to examine the differences among the five PAP protocols and between the two testing times. Our results showed that the post-test results were significantly improved compared to the pre-test for the vertical jump height (p = .015) in all PAP protocols. There was, however, an individual phenomenon of PAP in the response to all PAP protocols. In conclusion, this study found that resistance and plyometric exercise, whole body vibration, complex training and vibration complex training induce similar group PAP benefits. However, some athletes decreased their performances in some of the exercises in the study. Therefore, it is not recommended for coaches to arrange the exercises in a team setting.

High-performance liquid chromatography coupled with post-column dual-bioactivity assay for simultaneous screening of xanthine oxidase inhibitors and free radical scavengers from complex mixture.

Science.gov (United States)

Li, D Q; Zhao, J; Li, S P

2014-06-06

Xanthine oxidase (XO) can catalyze hypoxanthine and xanthine to generate uric acid and reactive oxygen species (ROS), including superoxide anion radical (O₂(•-)) and hydrogen peroxide. XO inhibitors and free radical scavengers are beneficial to the treatment of gout and many related diseases. In the present study, an on-line high-performance liquid chromatography (HPLC) coupled with post-column dual-bioactivity assay was established and successfully applied to simultaneously screening of XO inhibitors and free radical scavengers from a complex mixture, Oroxylum indicum extract. The integrated system of HPLC separation, bioactivity screening and mass spectrometry identification was proved to be simple and effective for rapid and sensitive screening of individual bioactive compounds in complex mixtures. Copyright © 2014 Elsevier B.V. All rights reserved.

Complex effects of fertilization on plant and herbivore performance in the presence of a plant competitor and activated carbon.

Science.gov (United States)

Mahdavi-Arab, Nafiseh; Meyer, Sebastian T; Mehrparvar, Mohsen; Weisser, Wolfgang W

2014-01-01

Plant-herbivore interactions are influenced by host plant quality which in turn is affected by plant growth conditions. Competition is the major biotic and nutrient availability a major abiotic component of a plant's growth environment. Yet, surprisingly few studies have investigated impacts of competition and nutrient availability on herbivore performance and reciprocal herbivore effects on plants. We studied growth of the specialist aphid, Macrosiphoniella tanacetaria, and its host plant tansy, Tanacetum vulgare, under experimental addition of inorganic and organic fertilizer crossed with competition by goldenrod, Solidago canadensis. Because of evidence that competition by goldenrod is mediated by allelopathic compounds, we also added a treatment with activated carbon. Results showed that fertilization increased, and competition with goldenrod decreased, plant biomass, but this was likely mediated by resource competition. There was no evidence from the activated carbon treatment that allelopathy played a role which instead had a fertilizing effect. Aphid performance increased with higher plant biomass and depended on plant growth conditions, with fertilization and AC increasing, and plant competition decreasing aphid numbers. Feedbacks of aphids on plant performance interacted with plant growth conditions in complex ways depending on the relative magnitude of the effects on plant biomass and aphid numbers. In the basic fertilization treatment, tansy plants profited from increased nutrient availability by accumulating more biomass than they lost due to an increased number of aphids under fertilization. When adding additional fertilizer, aphid numbers increased so high that tansy plants suffered and showed reduced biomass compared with controls without aphids. Thus, the ecological cost of an infestation with aphids depends on the balance of effects of growth conditions on plant and herbivore performance. These results emphasize the importance to investigate both

Complex effects of fertilization on plant and herbivore performance in the presence of a plant competitor and activated carbon.

Directory of Open Access Journals (Sweden)

Nafiseh Mahdavi-Arab

Full Text Available Plant-herbivore interactions are influenced by host plant quality which in turn is affected by plant growth conditions. Competition is the major biotic and nutrient availability a major abiotic component of a plant's growth environment. Yet, surprisingly few studies have investigated impacts of competition and nutrient availability on herbivore performance and reciprocal herbivore effects on plants. We studied growth of the specialist aphid, Macrosiphoniella tanacetaria, and its host plant tansy, Tanacetum vulgare, under experimental addition of inorganic and organic fertilizer crossed with competition by goldenrod, Solidago canadensis. Because of evidence that competition by goldenrod is mediated by allelopathic compounds, we also added a treatment with activated carbon. Results showed that fertilization increased, and competition with goldenrod decreased, plant biomass, but this was likely mediated by resource competition. There was no evidence from the activated carbon treatment that allelopathy played a role which instead had a fertilizing effect. Aphid performance increased with higher plant biomass and depended on plant growth conditions, with fertilization and AC increasing, and plant competition decreasing aphid numbers. Feedbacks of aphids on plant performance interacted with plant growth conditions in complex ways depending on the relative magnitude of the effects on plant biomass and aphid numbers. In the basic fertilization treatment, tansy plants profited from increased nutrient availability by accumulating more biomass than they lost due to an increased number of aphids under fertilization. When adding additional fertilizer, aphid numbers increased so high that tansy plants suffered and showed reduced biomass compared with controls without aphids. Thus, the ecological cost of an infestation with aphids depends on the balance of effects of growth conditions on plant and herbivore performance. These results emphasize the importance

Route complexity and simulated physical ageing negatively influence wayfinding

NARCIS (Netherlands)

Zijlstra, Emma; Hagedoorn, Mariet; Krijnen, Wim P.; Schans, van der Cornelis; Mobach, Mark P.

The aim of this age-simulation field experiment was to assess the influence of route complexity and physical ageing on wayfinding. Seventy-five people (aged 18-28) performed a total of 108 wayfinding tasks (i.e., 42 participants performed two wayfinding tasks and 33 performed one wayfinding task),

100 Gbps IM/DD links using quad-polarization: Performance, complexity, and power dissipation

DEFF Research Database (Denmark)

Saldaña Cercos, Silvia; Piels, Molly; Estaran Tolosa, Jose Manuel

2015-01-01

A computational complexity, power consumption, and receiver sensitivity analysis for three different scenarios for short-range direct detection links is presented: 1) quad-polarization, 2) wavelength division multiplexing (WDM), and 3) parallel optics. Results show that the power consumption pena...... sensitivity of 4.4 dBm...

Exploring the dynamic and complex integration of sustainability performance measurement into product development

DEFF Research Database (Denmark)

Rodrigues, Vinicius Picanco; Morioka, S.; Pigosso, Daniela Cristina Antelmi

2016-01-01

In order to deal with the complex and dynamic nature of sustainability integration into the product development process, this research explore the use of a qualitative System Dynamics approach by using the causal loop diagram (CLD) tool. A literature analysis was followed by a case study, aiming ...

Forward osmosis for oily wastewater reclamation: Multi-charged oxalic acid complexes as draw solutes

KAUST Repository

Ge, Qingchun

2017-06-11

Forward osmosis (FO) has demonstrated its merits in hybrid FO seawater desalination. However, FO may have a potential for other applications if suitable draw solutes are available. In this study, a series of novel draw solutes based on oxalic acid (OA)-transitional metal complexes are presented. Influential factors of FO performance have been systematically investigated by varying the transitional metals, cations of the complex draw solutes as well as the experimental conditions. Compared to NaCl and other recently synthesized draw solutes, the OA complexes show superior FO performance in terms of high water fluxes up to 27.5 and 89.1 LMH under the respective FO and PRO (pressure retarded osmosis) modes, both with negligible reverse solute fluxes. The features of octahedral geometry, abundant hydrophilic groups and ionic species are crucial for the OA complexes as appropriate draw solutes with satisfactory FO performance. Among the synthesized OA complexes, the ammonium salt of chromic complex (NH4-Cr-OA) outperforms others due to the presence of more ionic species in its complex system. NH4-Cr-OA also performs better than the typical NaCl draw solute in FO oily wastewater treatment with higher water recovery and negligible reverse fluxes. Dilute solutions of OA complexes have been reconcentrated through membrane distillation (MD) and reused to new round of FO processes. The OA complexes have demonstrated their suitability and superiority as a novel class of draw solutes for the FO process in this study.

Polyelectrolyte Complex Based Interfacial Drug Delivery System with Controlled Loading and Improved Release Performance for Bone Therapeutics

Directory of Open Access Journals (Sweden)

David Vehlow

2016-03-01

Full Text Available An improved interfacial drug delivery system (DDS based on polyelectrolyte complex (PEC coatings with controlled drug loading and improved release performance was elaborated. The cationic homopolypeptide poly(l-lysine (PLL was complexed with a mixture of two cellulose sulfates (CS of low and high degree of substitution, so that the CS and PLL solution have around equal molar charged units. As drugs the antibiotic rifampicin (RIF and the bisphosphonate risedronate (RIS were integrated. As an important advantage over previous PEC systems this one can be centrifuged, the supernatant discarded, the dense pellet phase (coacervate separated, and again redispersed in fresh water phase. This behavior has three benefits: (i Access to the loading capacity of the drug, since the concentration of the free drug can be measured by spectroscopy; (ii lower initial burst and higher residual amount of drug due to removal of unbound drug and (iii complete adhesive stability due to the removal of polyelectrolytes (PEL excess component. It was found that the pH value and ionic strength strongly affected drug content and release of RIS and RIF. At the clinically relevant implant material (Ti40Nb similar PEC adhesive and drug release properties compared to the model substrate were found. Unloaded PEC coatings at Ti40Nb showed a similar number and morphology of above cultivated human mesenchymal stem cells (hMSC compared to uncoated Ti40Nb and resulted in considerable production of bone mineral. RIS loaded PEC coatings showed similar effects after 24 h but resulted in reduced number and unhealthy appearance of hMSC after 48 h due to cell toxicity of RIS.

Low complexity symbol-wise beamforming for MIMO-OFDM systems

KAUST Repository

Lee, Hyun Ho

2011-12-01

In this paper, we consider a low complexity symbol-wise beamforming for MIMO-OFDM systems. We propose a non-iterative algorithm for the symbol-wise beamforming, which can provide the performance approaching that of the conventional symbol-wise beamforming based on the iterative algorithm. We demonstrate that our proposed scheme can reduce the computational complexity significantly. From our simulation results, it is evident that our proposed scheme leads to a negligible performance loss compared to the conventional symbol-wise beamforming regardless of spatial correlation or presence of co-channel interference. © 2011 IEEE.

Non-equilibrium phase transitions in complex plasma

International Nuclear Information System (INIS)

Suetterlin, K R; Raeth, C; Ivlev, A V; Thomas, H M; Khrapak, S; Zhdanov, S; Rubin-Zuzic, M; Morfill, G E; Wysocki, A; Loewen, H; Goedheer, W J; Fortov, V E; Lipaev, A M; Molotkov, V I; Petrov, O F

2010-01-01

Complex plasma being the 'plasma state of soft matter' is especially suitable for investigations of non-equilibrium phase transitions. Non-equilibrium phase transitions can manifest in dissipative structures or self-organization. Two specific examples are lane formation and phase separation. Using the permanent microgravity laboratory PK-3 Plus, operating onboard the International Space Station, we performed unique experiments with binary mixtures of complex plasmas that showed both lane formation and phase separation. These observations have been augmented by comprehensive numerical and theoretical studies. In this paper we present an overview of our most important results. In addition we put our results in context with research of complex plasmas, binary systems and non-equilibrium phase transitions. Necessary and promising future complex plasma experiments on phase separation and lane formation are briefly discussed.

Techniques for Automated Performance Analysis

Energy Technology Data Exchange (ETDEWEB)

Marcus, Ryan C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2014-09-02

The performance of a particular HPC code depends on a multitude of variables, including compiler selection, optimization flags, OpenMP pool size, file system load, memory usage, MPI configuration, etc. As a result of this complexity, current predictive models have limited applicability, especially at scale. We present a formulation of scientific codes, nodes, and clusters that reduces complex performance analysis to well-known mathematical techniques. Building accurate predictive models and enhancing our understanding of scientific codes at scale is an important step towards exascale computing.

Structured analysis and modeling of complex systems

Science.gov (United States)

Strome, David R.; Dalrymple, Mathieu A.

1992-01-01

The Aircrew Evaluation Sustained Operations Performance (AESOP) facility at Brooks AFB, Texas, combines the realism of an operational environment with the control of a research laboratory. In recent studies we collected extensive data from the Airborne Warning and Control Systems (AWACS) Weapons Directors subjected to high and low workload Defensive Counter Air Scenarios. A critical and complex task in this environment involves committing a friendly fighter against a hostile fighter. Structured Analysis and Design techniques and computer modeling systems were applied to this task as tools for analyzing subject performance and workload. This technology is being transferred to the Man-Systems Division of NASA Johnson Space Center for application to complex mission related tasks, such as manipulating the Shuttle grappler arm.

Characterizing Complexity of Containerized Cargo X-ray Images

Energy Technology Data Exchange (ETDEWEB)

Wang, Guangxing [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Martz, Harry [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Glenn, Steven [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Divin, Charles [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Birrer, Nat [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2016-08-19

X-ray imaging can be used to inspect cargos imported into the United States. In order to better understand the performance of X-ray inspection systems, the X-ray characteristics (density, complexity) of cargo need to be quantified. In this project, an image complexity measure called integrated power spectral density (IPSD) was studied using both DNDO engineered cargos and stream-of-commerce (SOC) cargos. A joint distribution of cargo density and complexity was obtained. A support vector machine was used to classify the SOC cargos into four categories to estimate the relative fractions.

Characterizing Complexity of Containerized Cargo X-ray Images

International Nuclear Information System (INIS)

Wang, Guangxing; Martz, Harry; Glenn, Steven; Divin, Charles; Birrer, Nat

2016-01-01

X-ray imaging can be used to inspect cargos imported into the United States. In order to better understand the performance of X-ray inspection systems, the X-ray characteristics (density, complexity) of cargo need to be quantified. In this project, an image complexity measure called integrated power spectral density (IPSD) was studied using both DNDO engineered cargos and stream-of-commerce (SOC) cargos. A joint distribution of cargo density and complexity was obtained. A support vector machine was used to classify the SOC cargos into four categories to estimate the relative fractions.

Association Between Gross-Motor and Executive Function Depends on Age and Motor Task Complexity

DEFF Research Database (Denmark)

Spedden, Meaghan E; Malling, Anne Sofie B; Andersen, Ken K

2017-01-01

The objective was to examine associations between motor and executive function across the adult lifespan and to investigate the role of motor complexity in these associations. Young, middle-aged and older adults (n = 82; 19-83y) performed two gross-motor tasks with different levels of complexity...... and a Stroop-like computer task. Performance was decreased in older adults. The association between motor and cognitive performance was significant for older adults in the complex motor task (p = 0.03, rs = -0.41), whereas no significant associations were found for young or middle-aged groups, suggesting...... that the link between gross-motor and executive function emerges with age and depends on motor complexity....

The CEO performance effect : Statistical issues and a complex fit perspective

NARCIS (Netherlands)

Blettner, D.P.; Chaddad, F.R.; Bettis, R.

2012-01-01

How CEOs affect strategy and performance is important to strategic management research. We show that sophisticated statistical analysis alone is problematic for establishing the magnitude and causes of CEO impact on performance. We discuss three problem areas that substantially distort the

Environmental layout complexity affects neural activity during navigation in humans.

Science.gov (United States)

Slone, Edward; Burles, Ford; Iaria, Giuseppe

2016-05-01

Navigating large-scale surroundings is a fundamental ability. In humans, it is commonly assumed that navigational performance is affected by individual differences, such as age, sex, and cognitive strategies adopted for orientation. We recently showed that the layout of the environment itself also influences how well people are able to find their way within it, yet it remains unclear whether differences in environmental complexity are associated with changes in brain activity during navigation. We used functional magnetic resonance imaging to investigate how the brain responds to a change in environmental complexity by asking participants to perform a navigation task in two large-scale virtual environments that differed solely in interconnection density, a measure of complexity defined as the average number of directional choices at decision points. The results showed that navigation in the simpler, less interconnected environment was faster and more accurate relative to the complex environment, and such performance was associated with increased activity in a number of brain areas (i.e. precuneus, retrosplenial cortex, and hippocampus) known to be involved in mental imagery, navigation, and memory. These findings provide novel evidence that environmental complexity not only affects navigational behaviour, but also modulates activity in brain regions that are important for successful orientation and navigation. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Autonomous Task Primitives for Complex Manipulation Operations

Data.gov (United States)

National Aeronautics and Space Administration — The goal of this research effort is to enable robots to autonomously perform the complex manipulation tasks that are necessary to maintain a spacecraft. Robots, like...

Metalloantibiotic Mn(II)-bacitracin complex mimicking manganese superoxide dismutase

International Nuclear Information System (INIS)

Piacham, Theeraphon; Isarankura-Na-Ayudhya, Chartchalerm; Nantasenamat, Chanin; Yainoy, Sakda; Ye Lei; Buelow, Leif; Prachayasittikul, Virapong

2006-01-01

Superoxide dismutase (SOD) activities of various metallobacitracin complexes were evaluated using the riboflavin-methionine-nitro blue tetrazolium assay. The radical scavenging activity of various metallobacitracin complexes was shown to be higher than those of the negative controls, e.g., free transition metal ions and metal-free bacitracin. The SOD activity of the complex was found to be in the order of Mn(II) > Cu(II) > Co(II) > Ni(II). Furthermore, the effect of bacitracin and their complexation to metals on various microorganisms was assessed by antibiotic susceptibility testing. Moreover, molecular modeling and quantum chemical calculation of the metallobacitracin complex was performed to evaluate the correlation of electrostatic charge of transition metal ions on the SOD activity

Yellow-green electroluminescence of samarium complexes of 8-hydroxyquinoline

Energy Technology Data Exchange (ETDEWEB)

Behzad, Sara Karimi; Najafi, Ezzatollah [Department of Chemistry Shahid Beheshti University G.C., Tehran 1983963113 (Iran, Islamic Republic of); Amini, Mostafa M., E-mail: m-pouramini@sbu.ac.ir [Department of Chemistry Shahid Beheshti University G.C., Tehran 1983963113 (Iran, Islamic Republic of); Janghouri, Mohammad; Mohajerani, Ezeddin [Laser Research Institute Shahid Beheshti University G.C., Tehran 1983963113 (Iran, Islamic Republic of); Ng, Seik Weng [Department of Chemistry, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2014-12-15

Four novel samarium complexes were prepared by reacting samarium(III) nitrate with 8-hydroxyquinoline, 2-methyl-8-hydroxyquinoline, and 1,10-phenanthroline and utilized as emitting materials in the electroluminescence device. All complexes were characterized by elemental analysis, infrared, UV–vis and {sup 1}H NMR spectroscopes and the molecular structure of a representative complex, [Sm{sub 2}(Me-HQ){sub 4}(NO{sub 3}){sub 6}] (1), was determined by single-crystal X-ray diffraction. Utilization of a π-conjugated (phenanthroline) ligand as a second ligand in the structure of the samarium complexes resulted in red shifts in both absorption and fluorescence spectra of complexes and moderately enhanced the photoluminescence intensity and the fluorescence quantum yield. The maximum emission peaks showed that a good correlation exists between the nature of the substituent group on the 8-hydroxyquinoline and the addition of the π-conjugated ligand in the structure of samarium complexes and emission wavelength. Devices with samarium(III) complexes with structure of ITO/PEDOT:PSS (90 nm)/PVK:PBD:Sm(III) complexes (75 nm)/Al (180 nm) were fabricated. In the electroluminescence (EL) spectra of the devices, a strong ligand-centered emission and narrow bands arising from the {sup 4}G{sub 5/2}→{sup 6}H{sub J} transitions (J=7/2, 9/2, and 11/2) of the samarium ion were observed for the complexes. The electroluminescent spectra of the samarium complexes were red-shifted as compared with the PVK:PBD blend. We believe that the electroluminescence performance of OLED devices based on samarium complexes relies on overlaps between the absorption of the samarium compounds and the emission of PVK:PBD. This revealed that it is possible to evaluate the electroluminescence performance of the samarium compounds-doped OLED devices based on the emission of PVK:PBD and the absorption of the dopants. - Highlights: • Four novel photoluminescence samarium complexes have been synthesized. �

pincer complex in Suzuki–Miyaura cross-coupling reaction under

Indian Academy of Sciences (India)

The recent focus of interest on pincer complexes is due to their extended utility in the field of homogeneous catalysis.1 Pincer complexes offer interesting possibili- ties both in terms of mechanistic understanding and cat- alytic performance.1b The high catalytic efficiency is attributed to the stable and compact geometry of the.

Virtual machine performance benchmarking.

Science.gov (United States)

Langer, Steve G; French, Todd

2011-10-01

The attractions of virtual computing are many: reduced costs, reduced resources and simplified maintenance. Any one of these would be compelling for a medical imaging professional attempting to support a complex practice on limited resources in an era of ever tightened reimbursement. In particular, the ability to run multiple operating systems optimized for different tasks (computational image processing on Linux versus office tasks on Microsoft operating systems) on a single physical machine is compelling. However, there are also potential drawbacks. High performance requirements need to be carefully considered if they are to be executed in an environment where the running software has to execute through multiple layers of device drivers before reaching the real disk or network interface. Our lab has attempted to gain insight into the impact of virtualization on performance by benchmarking the following metrics on both physical and virtual platforms: local memory and disk bandwidth, network bandwidth, and integer and floating point performance. The virtual performance metrics are compared to baseline performance on "bare metal." The results are complex, and indeed somewhat surprising.

Determination of 24-hour insulin infusion pattern by an artificial endocrine pancreas for intravenous insulin infusion with a miniature pump

DEFF Research Database (Denmark)

Kølendorf, K; Christiansen, J S; Bojsen, J

1981-01-01

UNLABELLED: Intravenous insulin infusion with a glucose controlled insulin infusion system (GCIIS) is known to restore glucose homeostasis. A simpler approach to improve blood glucose regulation is preprogrammed intravenous insulin infusion with portable pumps without sensor-mediated feedback. We...... report a study designed to evaluate whether the preprogrammed insulin infusion pattern to be used in the miniature insulin infusion pump (MIIP) could be optimized by concomitant employment of the GCIIS for blood glucose control. Six juvenile-onset insulin-dependent diabetics (mean age 31 yrs) were...... studied. Mean blood glucose (MBG) was 6.2 mmol/l +/- 0.5 (SD) during glucose controlled infusion and 5.3 +/- 0.6 during the combined MIIP + GCIIS-day. The insulin requirements calculated from the s.c. regimen (56 U +/- 10 SD) were identical to the GCIIS-measured (51 U +/- 14) and to the amounts delivered...

Enduring the shipboard stressor complex: a systems approach.

Science.gov (United States)

Comperatore, Carlos A; Rivera, Pik Kwan; Kingsley, Leonard

2005-06-01

A high incidence of physiological and psychological stressors characterizes the maritime work environment in many segments of the commercial maritime industry and in the military. Traditionally, crewmembers work embedded in a complex of stressors. Stressors rarely act independently because most occur concurrently, simultaneously taxing physical and mental resources. Stressors such as extreme environmental temperatures, long work hours, heavy mental and physical workload, authoritative leadership, isolation from family and loved ones, lack of exercise, and unhealthy diets often combine to degrade crewmember health and performance, particularly on long voyages. This complex system of interacting stressors affects the ability of maritime crewmembers to maintain adequate levels of alertness and performance. An analytical systems approach methodology is described here as a viable method to identify workplace stressors and track their systemic interactions. A systems-based program for managing the stressor complex is then offered, together with the empirical research supporting its efficacy. Included is an example implementation of a stressor-control program aboard a U.S. Coast Guard cutter.

Prevalence of E/A wave fusion and A wave truncation in DDD pacemaker patients with complete AV block under nominal AV intervals.

Directory of Open Access Journals (Sweden)

Wolfram C Poller

Full Text Available Optimization of the AV-interval (AVI in DDD pacemakers improves cardiac hemodynamics and reduces pacemaker syndromes. Manual optimization is typically not performed in clinical routine. In the present study we analyze the prevalence of E/A wave fusion and A wave truncation under resting conditions in 160 patients with complete AV block (AVB under the pre-programmed AVI. We manually optimized sub-optimal AVI.We analyzed 160 pacemaker patients with complete AVB, both in sinus rhythm (AV-sense; n = 129 and under atrial pacing (AV-pace; n = 31. Using Doppler analyses of the transmitral inflow we classified the nominal AVI as: a normal, b too long (E/A wave fusion or c too short (A wave truncation. In patients with a sub-optimal AVI, we performed manual optimization according to the recommendations of the American Society of Echocardiography.All AVB patients with atrial pacing exhibited a normal transmitral inflow under the nominal AV-pace intervals (100%. In contrast, 25 AVB patients in sinus rhythm showed E/A wave fusion under the pre-programmed AV-sense intervals (19.4%; 95% confidence interval (CI: 12.6-26.2%. A wave truncations were not observed in any patient. All patients with a complete E/A wave fusion achieved a normal transmitral inflow after AV-sense interval reduction (mean optimized AVI: 79.4 ± 13.6 ms.Given the rate of 19.4% (CI 12.6-26.2% of patients with a too long nominal AV-sense interval, automatic algorithms may prove useful in improving cardiac hemodynamics, especially in the subgroup of atrially triggered pacemaker patients with AV node diseases.

Performance Support Systems: Integrating AI, Hypermedia, and CBT to Enhance User Performance.

Science.gov (United States)

McGraw, Karen L.

1994-01-01

Examines the use of a performance support system (PSS) to enhance user performance on an operational system. Highlights include background information that describes the stimulus for PSS development; discussion of the major PSS components and the technology they require; and discussion of the design of a PSS for a complex database system.…

Forward osmosis for oily wastewater reclamation: Multi-charged oxalic acid complexes as draw solutes.

Science.gov (United States)

Ge, Qingchun; Amy, Gary Lee; Chung, Tai-Shung

2017-10-01

Forward osmosis (FO) has demonstrated its merits in hybrid FO seawater desalination. However, FO may have a potential for other applications if suitable draw solutes are available. In this study, a series of novel draw solutes based on oxalic acid (OA)-transitional metal complexes are presented. Influential factors of FO performance have been systematically investigated by varying the transitional metals, cations of the complex draw solutes as well as the experimental conditions. Compared to NaCl and other recently synthesized draw solutes, the OA complexes show superior FO performance in terms of high water fluxes up to 27.5 and 89.1 LMH under the respective FO and PRO (pressure retarded osmosis) modes, both with negligible reverse solute fluxes. The features of octahedral geometry, abundant hydrophilic groups and ionic species are crucial for the OA complexes as appropriate draw solutes with satisfactory FO performance. Among the synthesized OA complexes, the ammonium salt of chromic complex (NH 4 -Cr-OA) outperforms others due to the presence of more ionic species in its complex system. NH 4 -Cr-OA also performs better than the typical NaCl draw solute in FO oily wastewater treatment with higher water recovery and negligible reverse fluxes. Dilute solutions of OA complexes have been reconcentrated through membrane distillation (MD) and reused to new round of FO processes. The OA complexes have demonstrated their suitability and superiority as a novel class of draw solutes for the FO process in this study. Copyright © 2017 Elsevier Ltd. All rights reserved.

School Performance

Directory of Open Access Journals (Sweden)

Héctor A. Lamas

2015-03-01

Full Text Available The school performance study of students is, due to its relevance and complexity, one of the issues of major controversy in the educational research, and it has been given special attention in the last decades. This study is intended to show a conceptual approach to the school performance construct, contextualizing the reality in the regular basic education classrooms. The construct of learning approaches is presented as one of the factors that influences the school performance of students. Besides, an outlook of the empirical research works related to variables that are presented as relevant when explaining the reason for a specific performance in students is shown. Finally, some models and techniques allowing an appropriate study of school performance are presented.

Computer Program for Calculation of Complex Chemical Equilibrium Compositions, Rocket Performance, Incident and Reflected Shocks, and Chapman-Jouguet Detonations. Interim Revision, March 1976

Science.gov (United States)

Gordon, S.; Mcbride, B. J.

1976-01-01

A detailed description of the equations and computer program for computations involving chemical equilibria in complex systems is given. A free-energy minimization technique is used. The program permits calculations such as (1) chemical equilibrium for assigned thermodynamic states (T,P), (H,P), (S,P), (T,V), (U,V), or (S,V), (2) theoretical rocket performance for both equilibrium and frozen compositions during expansion, (3) incident and reflected shock properties, and (4) Chapman-Jouguet detonation properties. The program considers condensed species as well as gaseous species.

Feedback stabilization experiments using l = 2 equilibrium windings in Scyllac

International Nuclear Information System (INIS)

Bartsch, R.R.; Cantrell, E.L.; Gribble, R.F.; Freese, K.B.; Handy, L.E.; Kristal, R.; Miller, G.; Quinn, W.E.

1977-01-01

The confinement time in the Scyllac Sector Feedback Experiment has been extended with a pre-programmed equilibrium compensation force. This force was produced by driving a current with a flexible waveform in an additional set of l = 2 windings

Auditory Brainstem Response to Complex Sounds Predicts Self-Reported Speech-in-Noise Performance

Science.gov (United States)

Anderson, Samira; Parbery-Clark, Alexandra; White-Schwoch, Travis; Kraus, Nina

2013-01-01

Purpose: To compare the ability of the auditory brainstem response to complex sounds (cABR) to predict subjective ratings of speech understanding in noise on the Speech, Spatial, and Qualities of Hearing Scale (SSQ; Gatehouse & Noble, 2004) relative to the predictive ability of the Quick Speech-in-Noise test (QuickSIN; Killion, Niquette,…

Computations, Complexity, Experiments, and the World Outside Physics

International Nuclear Information System (INIS)

Kadanoff, L.P

2009-01-01

Computer Models in the Sciences and Social Sciences. 1. Simulation and Prediction in Complex Systems: the Good the Bad and the Awful. This lecture deals with the history of large-scale computer modeling mostly in the context of the U.S. Department of Energy's sponsorship of modeling for weapons development and innovation in energy sources. 2. Complexity: Making a Splash-Breaking a Neck - The Making of Complexity in Physical System. For ages thinkers have been asking how complexity arise. The laws of physics are very simple. How come we are so complex? This lecture tries to approach this question by asking how complexity arises in physical fluids. 3. Forrester, et. al. Social and Biological Model-Making The partial collapse of the world's economy has raised the question of whether we could improve the performance of economic and social systems by a major effort on creating understanding via large-scale computer models. (author)

The step complexity measure for emergency operating procedures: measure verification

International Nuclear Information System (INIS)

Park, Jinkyun; Jung, Wondea; Ha, Jaejoo; Park, Changkue

2002-01-01

In complex systems, such as nuclear power plants (NPPs) or airplane control systems, human errors play a major role in many accidents. Therefore, to prevent an occurrence of accidents or to ensure system safety, extensive effort has been made to identify significant factors that can cause human errors. According to related studies, written manuals or operating procedures are revealed as one of the most important factors, and the understandability is pointed out as one of the major reasons for procedure-related human errors. Many qualitative checklists are suggested to evaluate emergency operating procedures (EOPs) of NPPs. However, since qualitative evaluations using checklists have some drawbacks, a quantitative measure that can quantify the complexity of EOPs is very necessary to compensate for them. In order to quantify the complexity of steps included in EOPs, Park et al. suggested the step complexity (SC) measure. In addition, to ascertain the appropriateness of the SC measure, averaged step performance time data obtained from emergency training records for the loss of coolant accident and the excess steam dump event were compared with estimated SC scores. Although averaged step performance time data show good correlation with estimated SC scores, conclusions for some important issues that have to be clarified to ensure the appropriateness of the SC measure were not properly drawn because of lack of backup data. In this paper, to clarify remaining issues, additional activities to verify the appropriateness of the SC measure are performed using averaged step performance time data obtained from emergency training records. The total number of available records is 36, and training scenarios are the steam generator tube rupture and the loss of all feedwater. The number of scenarios is 18 each. From these emergency training records, averaged step performance time data for 30 steps are retrieved. As the results, the SC measure shows statistically meaningful

Control of complex physically simulated robot groups

Science.gov (United States)

Brogan, David C.

2001-10-01

Actuated systems such as robots take many forms and sizes but each requires solving the difficult task of utilizing available control inputs to accomplish desired system performance. Coordinated groups of robots provide the opportunity to accomplish more complex tasks, to adapt to changing environmental conditions, and to survive individual failures. Similarly, groups of simulated robots, represented as graphical characters, can test the design of experimental scenarios and provide autonomous interactive counterparts for video games. The complexity of writing control algorithms for these groups currently hinders their use. A combination of biologically inspired heuristics, search strategies, and optimization techniques serve to reduce the complexity of controlling these real and simulated characters and to provide computationally feasible solutions.

Frontal cortex and hippocampus neurotransmitter receptor complex level parallels spatial memory performance in the radial arm maze.

Science.gov (United States)

Shanmugasundaram, Bharanidharan; Sase, Ajinkya; Miklosi, András G; Sialana, Fernando J; Subramaniyan, Saraswathi; Aher, Yogesh D; Gröger, Marion; Höger, Harald; Bennett, Keiryn L; Lubec, Gert

2015-08-01

Several neurotransmitter receptors have been proposed to be involved in memory formation. However, information on receptor complexes (RCs) in the radial arm maze (RAM) is missing. It was therefore the aim of this study to determine major neurotransmitter RCs levels that are modulated by RAM training because receptors are known to work in homo-or heteromeric assemblies. Immediate early gene Arc expression was determined by immunohistochemistry to show if prefrontal cortices (PFC) and hippocampi were activated following RAM training as these regions are known to be mainly implicated in spatial memory. Twelve rats per group, trained and untrained in the twelve arm RAM were used, frontal cortices and hippocampi were taken, RCs in membrane protein were quantified by blue-native PAGE immunoblotting. RCs components were characterised by co-immunoprecipitation followed by mass spectrometrical analysis and by the use of the proximity ligation assay. Arc expression was significantly higher in PFC of trained as compared to untrained rats whereas it was comparable in hippocampi. Frontal cortical levels of RCs containing AMPA receptors GluA1, GluA2, NMDA receptors GluN1 and GluN2A, dopamine receptor D1, acetylcholine nicotinic receptor alpha 7 (nAChR-α7) and hippocampal levels of RCs containing D1, GluN1, GluN2B and nAChR-α7 were increased in the trained group; phosphorylated dopamine transporter levels were decreased in the trained group. D1 and GluN1 receptors were shown to be in the same complex. Taken together, distinct RCs were paralleling performance in the RAM which is relevant for interpretation of previous and design of future work on RCs in memory studies. Copyright © 2015 Elsevier B.V. All rights reserved.

The Use of Conjunctions in Cognitively Simple versus Complex Oral L2 Tasks

Science.gov (United States)

Michel, Marije C.

2013-01-01

The present study explores the use of conjunctions in simple versus complex argumentative tasks performed by second language (L2) learners as a specific measure for the amount of reasoning involved in task performance. The Cognition Hypothesis (Robinson, 2005) states that an increase in cognitive task complexity promotes improvements in L2…

The Importance of Team Sex Composition in Team-Training Research Employing Complex Psychomotor Tasks.

Science.gov (United States)

Jarrett, Steven M; Glaze, Ryan M; Schurig, Ira; Arthur, Winfred

2017-08-01

The relationship between team sex composition and team performance on a complex psychomotor task was examined because these types of tasks are commonly used in the lab-based teams literature. Despite well-documented sex-based differences on complex psychomotor tasks, the preponderance of studies-mainly lab based-that use these tasks makes no mention of the sex composition of teams across or within experimental conditions. A sample of 123 four-person teams with varying team sex composition learned and performed a complex psychomotor task, Steal Beasts Pro PE. Each team completed a 5-hr protocol whereby they conducted several performance missions. The results indicated significant large mean differences such that teams with larger proportions of males had higher performance scores. These findings demonstrate the potential effect of team sex composition on the validity of studies that use complex psychomotor tasks to explore and investigate team performance-related phenomena when (a) team sex composition is not a focal variable of interest and (b) it is not accounted for or controlled. Given the proclivity of complex psychomotor action-based tasks used in lab-based team studies, it is important to understand and control for the impact of team sex composition on team performance. When team sex composition is not controlled for, either methodologically or statistically, it may affect the validity of the results in teams studies using these types of tasks.

Application of colony complex algorithm to nuclear component optimization design

International Nuclear Information System (INIS)

Yan Changqi; Li Guijing; Wang Jianjun

2014-01-01

Complex algorithm (CA) has got popular application to the region of nuclear engineering. In connection with the specific features of the application of traditional complex algorithm (TCA) to the optimization design in engineering structures, an improved method, colony complex algorithm (CCA), was developed based on the optimal combination of many complexes, in which the disadvantages of TCA were overcame. The optimized results of benchmark function show that CCA has better optimizing performance than TCA. CCA was applied to the high-pressure heater optimization design, and the optimization effect is obvious. (authors)

Cost and performance analysis of physical security systems

International Nuclear Information System (INIS)

Hicks, M.J.; Yates, D.; Jago, W.H.; Phillips, A.W.

1998-04-01

Analysis of cost and performance of physical security systems can be a complex, multi-dimensional problem. There are a number of point tools that address various aspects of cost and performance analysis. Increased interest in cost tradeoffs of physical security alternatives has motivated development of an architecture called Cost and Performance Analysis (CPA), which takes a top-down approach to aligning cost and performance metrics. CPA incorporates results generated by existing physical security system performance analysis tools, and utilizes an existing cost analysis tool. The objective of this architecture is to offer comprehensive visualization of complex data to security analysts and decision-makers

Individual differences in bodily freezing predict emotional biases in decision making

NARCIS (Netherlands)

Ly, V.; Huys, Q.; Stins, J.F.; Roelofs, K.; Cools, R.

2014-01-01

Instrumental decision making has long been argued to be vulnerable to emotional responses. Literature on multiple decision making systems suggests that this emotional biasing might reflect effects of a system that regulates innately specified, evolutionarily preprogrammed responses. To test this

Quantum chemical investigation of levofloxacin-boron complexes: A computational approach

Science.gov (United States)

Sayin, Koray; Karakaş, Duran

2018-04-01

Quantum chemical calculations are performed over some boron complexes with levofloxacin. Boron complex with fluorine atoms are optimized at three different methods (HF, B3LYP and M062X) with 6-31 + G(d) basis set. The best level is determined as M062X/6-31 + G(d) by comparison of experimental and calculated results of complex (1). The other complexes are optimized by using the best level. Structural properties, IR and NMR spectrum are examined in detail. Biological activities of mentioned complexes are investigated by some quantum chemical descriptors and molecular docking analyses. As a result, biological activities of complex (2) and (4) are close to each other and higher than those of other complexes. Additionally, NLO properties of mentioned complexes are investigated by some quantum chemical parameters. It is found that complex (3) is the best candidate for NLO applications.

A Performance Assessment of an Airborne Separation Assistance System Using Realistic Complex Traffic Flows

Science.gov (United States)

Smith, Jeremy C.; Bussink, Frank J. L.

2008-01-01

This paper presents the results from a study that investigates the performance of a tactical Airborne Separation Assistance System (ASAS) in en route airspace, under varying demand levels, with realistic traffic flows. The ASAS concept studied here allows flight crews of equipped aircraft to perform separation from other air traffic autonomously. This study addresses the tactical aspects of an ASAS using aircraft state data (i.e. position and velocity) to detect and resolve projected conflicts. In addition, use of a conflict prevention system helps ASAS-equipped aircraft avoid maneuvers that may cause new conflicts. ASAS-capable aircraft are equipped with satellite-based navigation and Automatic Dependent Surveillance Broadcast (ADS-B) for transmission and receipt of aircraft state data. In addition to tactical conflict detection and resolution (CD&R), a complete, integrated ASAS is likely to incorporate a strategic CD&R component with a longer look-ahead time, using trajectory intent information. A system-wide traffic flow management (TFM) component, located at the FAA command center helps aircraft to avoid regions of excessive traffic density and complexity. A Traffic Alert and Collision Avoidance System (TCAS), as used today is the system of last resort. This integrated approach avoids sole reliance on the use of the tactical CD&R studied here, but the tactical component remains a critical element of the complete ASAS. The focus of this paper is to determine to what extent the proposed tactical component of ASAS alone can maintain aircraft separation at demand levels up to three times that of current traffic. The study also investigates the effect of mixing ASAS-equipped aircraft with unequipped aircraft (i.e. current day) that do not have the capability to self-separate. Position and velocity data for unequipped aircraft needs to be available to ASASequipped. Most likely, for this future concept, state data would be available from instrument flight rules (IFR

Synthesis and structure determination of a stable organometallic uranium(V) imine complex and its isolobal anionic U(IV)-ate complex

Energy Technology Data Exchange (ETDEWEB)

Sharma, M.; Botoshanskii, M.; Eisen, M.S. [Schulich Faculty of Chemistry, and Institute of Catalysis Science and Technology, Technion Israel Institute of Technology, Haifa (Israel); Bannenberg, Th.; Tamm, M. [Institut fur Anorganische und Analytische Chemie, Technische Universitat Braunschweig (Germany)

2010-06-15

The reaction of one equivalent of Cp*{sub 2}UCl{sub 2} with 2-(trimethylsilyl-imino)-1,3-di-tert-butyl-imidazoline in boiling toluene afforded a one electron oxidation of the uranium metal and the opening of the N-heterocyclic ring, resulting in the formation of an organometallic uranium(V) imine complex. This complex crystallized with one molecule of toluene in the unit cell, and its solid-state structure was determined by X-ray diffraction analysis. When the same reaction was performed in perdeuterated toluene, a myriad of organometallic complexes were obtained, however, when equimolar amounts of water were used in toluene, the same complex was obtained, and its solid state characterization shows two independent molecules in the unit cell with an additional water molecule. For comparison of the geometric parameters, the corresponding isolobal anionic uranium(IV) complex [Cp*{sub 2}UCl{sub 3}]{sup -} was synthesized by the reaction of Cp*{sub 2}UCl{sub 2} with 1,3-di-tert-butyl-imidazolium chloride, and the resulting U(IV)-ate complex was characterized by X-ray diffraction analysis. (authors)

Performing Brexit

DEFF Research Database (Denmark)

Adler-Nissen, Rebecca; Galpin, Charlotte; Rosamond, Ben

2017-01-01

constructed from the outside. Brexit signifies more than the technical complexities of the UK withdrawing from the European Union. It works both as a promise of a different future and performatively to establish a particular past. Brexit works as a frame with potential to shape perceptions in three domains...

Advances in ultra-high performance liquid chromatography coupled to tandem mass spectrometry for sensitive detection of several food allergens in complex and processed foodstuffs.

Science.gov (United States)

Planque, M; Arnould, T; Dieu, M; Delahaut, P; Renard, P; Gillard, N

2016-09-16

Sensitive detection of food allergens is affected by food processing and foodstuff complexity. It is therefore a challenge to detect cross-contamination in food production that could endanger an allergic customer's life. Here we used ultra-high performance liquid chromatography coupled to tandem mass spectrometry for simultaneous detection of traces of milk (casein, whey protein), egg (yolk, white), soybean, and peanut allergens in different complex and/or heat-processed foodstuffs. The method is based on a single protocol (extraction, trypsin digestion, and purification) applicable to the different tested foodstuffs: chocolate, ice cream, tomato sauce, and processed cookies. The determined limits of quantitation, expressed in total milk, egg, peanut, or soy proteins (and not soluble proteins) per kilogram of food, are: 0.5mg/kg for milk (detection of caseins), 5mg/kg for milk (detection of whey), 2.5mg/kg for peanut, 5mg/kg for soy, 3.4mg/kg for egg (detection of egg white), and 30.8mg/kg for egg (detection of egg yolk). The main advantage is the ability of the method to detect four major food allergens simultaneously in processed and complex matrices with very high sensitivity and specificity. Copyright © 2016 Elsevier B.V. All rights reserved.

Discovering functional interdependence relationship in PPI networks for protein complex identification.

Science.gov (United States)

Lam, Winnie W M; Chan, Keith C C

2012-04-01

Protein molecules interact with each other in protein complexes to perform many vital functions, and different computational techniques have been developed to identify protein complexes in protein-protein interaction (PPI) networks. These techniques are developed to search for subgraphs of high connectivity in PPI networks under the assumption that the proteins in a protein complex are highly interconnected. While these techniques have been shown to be quite effective, it is also possible that the matching rate between the protein complexes they discover and those that are previously determined experimentally be relatively low and the "false-alarm" rate can be relatively high. This is especially the case when the assumption of proteins in protein complexes being more highly interconnected be relatively invalid. To increase the matching rate and reduce the false-alarm rate, we have developed a technique that can work effectively without having to make this assumption. The name of the technique called protein complex identification by discovering functional interdependence (PCIFI) searches for protein complexes in PPI networks by taking into consideration both the functional interdependence relationship between protein molecules and the network topology of the network. The PCIFI works in several steps. The first step is to construct a multiple-function protein network graph by labeling each vertex with one or more of the molecular functions it performs. The second step is to filter out protein interactions between protein pairs that are not functionally interdependent of each other in the statistical sense. The third step is to make use of an information-theoretic measure to determine the strength of the functional interdependence between all remaining interacting protein pairs. Finally, the last step is to try to form protein complexes based on the measure of the strength of functional interdependence and the connectivity between proteins. For performance evaluation

A comparative investigation on absorption performances of three expanded graphite-based complex materials for toluene

International Nuclear Information System (INIS)

Li Shande; Tian Shuanghong; Feng Yunfeng; Lei Jiajia; Wang, Piaopiao; Xiong Ya

2010-01-01

Three kinds of expanded graphite-based complex materials were prepared to absorb toluene by dispersing plant oil, animal oil and mineral oil on the surface of expanded graphite, respectively. These complex materials were characterized by scanning electronic micrograph, contact angle meter and Brunauer-Emmett-Teller surface area. And their absorption capacities for toluene were comparatively investigated. The results showed that the surfaces of the three types of sorbents were very hydrophobic and nonporous, but they all had excellent absorption capacities for toluene. And their absorption capacities were proportional to the toluene concentration in streams and decreased differently with increasing the absorption temperature. It was noteworthy that the absorption capacities varied with the unsaturated degree of the complex materials and kept unchanged under different relative humidities of streams. Moreover, the regeneration experiments showed that after 15-run regeneration the absorption capacities of expanded graphite modified by mineral oil almost kept unchanged, while that of expanded graphite loaded plant oil and animal oil dropped by 157 and 93.6 mg g -1 , respectively. The losses of their absorption capacities were ascribed to the destruction of their unsaturated carbon bounds.

Toward a Learning Science for Complex Crowdsourcing Tasks

Science.gov (United States)

Doroudi, Shayan; Kamar, Ece; Brunskill, Emma; Horvitz, Eric

2016-01-01

We explore how crowdworkers can be trained to tackle complex crowdsourcing tasks. We are particularly interested in training novice workers to perform well on solving tasks in situations where the space of strategies is large and workers need to discover and try different strategies to be successful. In a first experiment, we perform a comparison…

Complex chemistry

International Nuclear Information System (INIS)

Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

2006-06-01

This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.

Harnessing Photochemical Shrinkage in Direct Laser Writing for Shape Morphing of Polymer Sheets.

Science.gov (United States)

Bauhofer, Anton A; Krödel, Sebastian; Rys, Jan; Bilal, Osama R; Constantinescu, Andrei; Daraio, Chiara

2017-11-01

Structures that change their shape in response to external stimuli unfold possibilities for more efficient and versatile production of 3D objects. Direct laser writing (DLW) is a technique based on two-photon polymerization that allows the fabrication of microstructures with complex 3D geometries. Here, it is shown that polymerization shrinkage in DLW can be utilized to create structures with locally controllable residual stresses that enable programmable, self-bending behavior. To demonstrate this concept, planar and 3D-structured sheets are preprogrammed to evolve into bio-inspired shapes (lotus flowers and shark skins). The fundamental mechanisms that control the self-bending behavior are identified and tested with microscale experiments. Based on the findings, an analytical model is introduced to quantitatively predict bending curvatures of the fabricated sheets. The proposed method enables simple fabrication of objects with complex geometries and precisely controllable shape morphing potential, while drastically reducing the required fabrication times for producing 3D, hierarchical microstructures over large areas in the order of square centimeters. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Managing airlines: the cost of complexity

Energy Technology Data Exchange (ETDEWEB)

Trapote-Barreira, C.; Deutschmann, A.; Robuste, F.

2016-07-01

This paper is dedicated to the structure of airline networks as a sink of efficient airline operations. Parameters of complexity were derived and mirrored on level of service as well as efficiency parameters. Airlines usually considerers an operational overhead to predict the total flight operation cost. This parameter includes the expected cost for disruptions and delays. When an airline has to mobilize an aircraft in a base for recovering the service or for breaking an emergent dynamic, then it is running extra costs. The cost of managing complexity in the airline industry has a direct impact on profit and loss account. Therefore, this paper presents an integrated approach to evaluate this cost, based on padding and aircrafts dedicated to recover disruptions. Finally, some additional indicators are derived to evaluate reliability improvement as part of complex performance. (Author)

Combined effect of using near-infrared spectroscopy for nutritional evaluation of feed ingredients and non-starch polysaccharide carbohydrase complex on performance of broiler chickens.

Science.gov (United States)

Montanhini Neto, Roberto; N'Guetta, Eric; Gady, Cecile; Francesch, Maria; Preynat, Aurélie

2017-12-01

This study was carried out to evaluate the combined effect of using near-infrared spectroscopy (NIRS) for nutritional evaluation of feed ingredients and the addition of non-starch polysaccharide carbohydrase complex (NSP enzymes) on the growth performance of broilers fed diets produced with low-quality wheat and soybean meal. A 2 × 2 trial design was performed, with seven replicates of 40 male Ross 308 broilers per treatment, evaluating the effect of the addition of NSP enzymes and the ingredients' nutritional matrix based on table values or NIRS values. Diets without added enzymes were formulated to reach nutritional requirements, whereas diets with enzymes were reformulated, reducing the apparent metabolizable energy (AME) by 85 kcal/kg. In the overall period (days 0-35), broilers fed diets formulated using NIRS values had higher (P nutritional approaches are efficient in improving broilers' performances by themselves and even more so when they are combined. © 2017 Japanese Society of Animal Science.

Younger and older jurors: the influence of environmental supports on memory performance and decision making in complex trials.

Science.gov (United States)

Fitzgerald, J M

2000-11-01

This study compared memory and decision making by younger (aged 19-35) and older (aged 55-75) adults who had viewed a 2-hr video of a complex civil trial. Participants were tested for free recall, recognition memory, source identification, and the accuracy of their verdicts. The experiment manipulated (a) note taking during the trial and (b) timing of judicial instructions: either before (preinstructed) or after (standard) the presentation of relevant evidence. Judicial instructions provide jurors with a framework for understanding legal concepts such as liability and compensatory damages. Both younger and older adults provided more detailed and cohesive accounts when they were given judicial instructions before the evidence. Other benefits of preinstruction to memory and decision making were limited to older adults. Note-taking effects were generally limited but were consistent across age groups. The results highlight the potential value of relatively simple interventions for improving cognitive performance in a real-world setting.

Finding optimal interaction interface alignments between biological complexes

KAUST Repository

Cui, Xuefeng; Naveed, Hammad; Gao, Xin

2015-01-01

Motivation: Biological molecules perform their functions through interactions with other molecules. Structure alignment of interaction interfaces between biological complexes is an indispensable step in detecting their structural similarities, which

On-Line QRS Complex Detection Using Wavelet Filtering

National Research Council Canada - National Science Library

Szilagyi, L

2001-01-01

...: first a wavelet transform filtering is applied to the signal, then QRS complex localization is performed using a maximum detection and peak classification algorithm The algorithm has been tested...

Humanoid assessing rehabilitative exercises.

Science.gov (United States)

Simonov, M; Delconte, G

2015-01-01

This article is part of the Focus Theme of Methods of Information in Medicine on "New Methodologies for Patients Rehabilitation". The article presents the approach in which the rehabilitative exercise prepared by healthcare professional is encoded as formal knowledge and used by humanoid robot to assist patients without involving other care actors. The main objective is the use of humanoids in rehabilitative care. An example is pulmonary rehabilitation in COPD patients. Another goal is the automated judgment functionality to determine how the rehabilitation exercise matches the pre-programmed correct sequence. We use the Aldebaran Robotics' NAO humanoid to set up artificial cognitive application. Pre-programmed NAO induces elderly patient to undertake humanoid-driven rehabilitation exercise, but needs to evaluate the human actions against the correct template. Patient is observed using NAO's eyes. We use the Microsoft Kinect SDK to extract motion path from the humanoid's recorded video. We compare human- and humanoid-operated process sequences by using the Dynamic Time Warping (DTW) and test the prototype. This artificial cognitive software showcases the use of DTW algorithm to enable humanoids to judge in near real-time about the correctness of rehabilitative exercises performed by patients following the robot's indications. One could enable better sustainable rehabilitative care services in remote residential settings by combining intelligent applications piloting humanoids with the DTW pattern matching algorithm applied at run time to compare humanoid- and human-operated process sequences. In turn, it will lower the need of human care.

Geometric and Algebraic Approaches in the Concept of Complex Numbers

Science.gov (United States)

Panaoura, A.; Elia, I.; Gagatsis, A.; Giatilis, G.-P.

2006-01-01

This study explores pupils' performance and processes in tasks involving equations and inequalities of complex numbers requiring conversions from a geometric representation to an algebraic representation and conversions in the reverse direction, and also in complex numbers problem solving. Data were collected from 95 pupils of the final grade from…

Real and complex boson expansions in even-even deformed nuclei

International Nuclear Information System (INIS)

Silvestre-Brac, B.; Piepenbring, R.

1977-01-01

Analysis of real and complex boson expansions of the Kishimoto-Tamura type is performed in a deformed basis in order to allow a further study of the anharmonicities of vibrations in deformed nuclei. It is shown that complex solutions cannot be found in the cases where no real one exists. (Auth.)

MEASURING ACCURACY AND COMPLEXITY OF AN L2 LEARNER’S ORAL PRODUCTION

Directory of Open Access Journals (Sweden)

Teguh Khaerudin

2015-03-01

Full Text Available This paper aims at examining the influence of different tasks on the degree of task performance in a second language learner’s oral production. The underlying assumption is that among the three aspects of language performance in L2, i.e. fluency, accuracy, and complexity, learners may prioritize only one of them (Ellis & Barkhuizen, 2005, p. 150 and that their decision to prioritize one particular area of language performance may be determined by the characteristics of the task given to the learners (Skehan & Foster, 1997. Having a written record of an oral production, the writer focuses this study on determining the degree of complexity and accuracy, and analyzing whether the different tasks change the level of learner’s oral performance. The results show that learner’s accuracy from both tasks remains in the same level. However, both task conditions, which do not allow speech plan, result in no improvement in accuracy level and a minor improvement in the complexity level.

IC-tagged proteins are able to interact with each other and perform complex reactions when integrated into muNS-derived inclusions.

Science.gov (United States)

Brandariz-Nuñez, Alberto; Otero-Romero, Iria; Benavente, Javier; Martinez-Costas, Jose M

2011-09-20

We have recently developed a versatile tagging system (IC-tagging) that causes relocation of the tagged proteins to ARV muNS-derived intracellular globular inclusions. In the present study we demonstrate (i) that the IC-tag can be successfully fused either to the amino or carboxyl terminus of the protein to be tagged and (ii) that IC-tagged proteins are able to interact between them and perform complex reactions that require such interactions while integrated into muNS inclusions, increasing the versatility of the IC-tagging system. Also, our studies with the DsRed protein add some light on the structure/function relationship of the evolution of DsRed chromophore. Copyright © 2011 Elsevier B.V. All rights reserved.

The effects of familiarity and complexity on appraisal of complex songs by cochlear implant recipients and normal hearing adults.

Science.gov (United States)

Gfeller, Kate; Christ, Aaron; Knutson, John; Witt, Shelley; Mehr, Maureen

2003-01-01

The purposes of this study were (a) to develop a test of complex song appraisal that would be suitable for use with adults who use a cochlear implant (assistive hearing device) and (b) to compare the appraisal ratings (liking) of complex songs by adults who use cochlear implants (n = 66) with a comparison group of adults with normal hearing (n = 36). The article describes the development of a computerized test for appraisal, with emphasis on its theoretical basis and the process for item selection of naturalistic stimuli. The appraisal test was administered to the 2 groups to determine the effects of prior song familiarity and subjective complexity on complex song appraisal. Comparison of the 2 groups indicates that the implant users rate 2 of 3 musical genres (country western, pop) as significantly more complex than do normal hearing adults, and give significantly less positive ratings to classical music than do normal hearing adults. Appraisal responses of implant recipients were examined in relation to hearing history, age, performance on speech perception and cognitive tests, and musical background.

Application of a Complex Lead Compensator for a Laser Guided Missile

Science.gov (United States)

Akhila, M. R.; Gopika, S.; Abraham, R. J.

2013-01-01

This paper discusses the application of a lead compensator with complex pole and complex zero for a missile. It is compared with a lead compensator with real pole and real zero. A typical laser guided missile control system is considered for the performance comparison of both the compensators. Simulation studies carried out with MATLAB brings out the scope of using complex compensator in missile guided systems.

A low complexity VBLAST OFDM detection algorithm for wireless LAN systems

NARCIS (Netherlands)

Wu, Y.; Lei, Zhongding; Sun, Sumei

2004-01-01

A low complexity detection algorithm for VBLAST OFDM system is presented. Using the fact that the correlation among neighboring subcarriers is high for wireless LAN channels, this algorithm significantly reduces the complexity of VBLAST OFDM detection. The performance degradation of the proposed

The ESTER particle and plasma analyzer complex for the Phobos mission

Energy Technology Data Exchange (ETDEWEB)

Afonin, V.V.; Shutte, N.M. (AN SSSR, Moscow (USSR). Inst. Kosmicheskikh Issledovanij); McKenna-Lawlor, S.; Rusznyak, P. (Space Technology Ireland Ltd., Maynooth (Ireland)); Kiraly, P.; Szabo, L.; Szalai, S.; Szucs, I.T.; Varhalmi, L. (Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics); Marsden, R. (European Space Agency, Noordwijk (Netherlands). Space Science Dept.); Richter, A.; Witte, M. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau (Germany, F.R.))

1990-05-01

The ESTER particle and plasma analyzer system for the Phobos Mission comprised a complex of three instruments (LET, SLED and HARP) serviced by a common Data Processing Unit. An account is provided of this complex, its objectives and excellent performance in space. (orig.).

SUPERCOMPUTER SIMULATION OF CRITICAL PHENOMENA IN COMPLEX SOCIAL SYSTEMS

Directory of Open Access Journals (Sweden)

Petrus M.A. Sloot

2014-09-01

Full Text Available The paper describes a problem of computer simulation of critical phenomena in complex social systems on a petascale computing systems in frames of complex networks approach. The three-layer system of nested models of complex networks is proposed including aggregated analytical model to identify critical phenomena, detailed model of individualized network dynamics and model to adjust a topological structure of a complex network. The scalable parallel algorithm covering all layers of complex networks simulation is proposed. Performance of the algorithm is studied on different supercomputing systems. The issues of software and information infrastructure of complex networks simulation are discussed including organization of distributed calculations, crawling the data in social networks and results visualization. The applications of developed methods and technologies are considered including simulation of criminal networks disruption, fast rumors spreading in social networks, evolution of financial networks and epidemics spreading.

Towards exoskeletons with balance capacities

NARCIS (Netherlands)

van der Kooij, Herman; van Asseldonk, Edwin H.F.; Vlutters, Mark; González-Vargas, José; Ibáñez, Jaime; Contreras-Vidal, Jose L.; van der Kooij, Herman; Pons, José Luis

2017-01-01

Current exoskeletons replay pre-programmed trajectories at the actuated joints. Towards the employment of exoskeletons with more flexible and adaptive behavior, we investigate human balance control during gait. We study human balance control by applying brief force pulses at the pelvis in different

A framework for handling and combining inaccuracy propagation in robot subtasks for industrial assembly

DEFF Research Database (Denmark)

Buch, Jacob P.; Petersen, Henrik G.

2017-01-01

time can be substantial. Hence, hard automation is only suitable for large batch sizes. However, with the upcoming programming paradigms based on joining preprogrammed subtasks (skills) to a complete solution, the programming time can be shortened significantly. Skills are subtasks with well defined...

Automatic QRS complex detection using two-level convolutional neural network.

Science.gov (United States)

Xiang, Yande; Lin, Zhitao; Meng, Jianyi

2018-01-29

The QRS complex is the most noticeable feature in the electrocardiogram (ECG) signal, therefore, its detection is critical for ECG signal analysis. The existing detection methods largely depend on hand-crafted manual features and parameters, which may introduce significant computational complexity, especially in the transform domains. In addition, fixed features and parameters are not suitable for detecting various kinds of QRS complexes under different circumstances. In this study, based on 1-D convolutional neural network (CNN), an accurate method for QRS complex detection is proposed. The CNN consists of object-level and part-level CNNs for extracting different grained ECG morphological features automatically. All the extracted morphological features are used by multi-layer perceptron (MLP) for QRS complex detection. Additionally, a simple ECG signal preprocessing technique which only contains difference operation in temporal domain is adopted. Based on the MIT-BIH arrhythmia (MIT-BIH-AR) database, the proposed detection method achieves overall sensitivity Sen = 99.77%, positive predictivity rate PPR = 99.91%, and detection error rate DER = 0.32%. In addition, the performance variation is performed according to different signal-to-noise ratio (SNR) values. An automatic QRS detection method using two-level 1-D CNN and simple signal preprocessing technique is proposed for QRS complex detection. Compared with the state-of-the-art QRS complex detection approaches, experimental results show that the proposed method acquires comparable accuracy.

Predictive modelling of complex agronomic and biological systems.

Science.gov (United States)

Keurentjes, Joost J B; Molenaar, Jaap; Zwaan, Bas J

2013-09-01

Biological systems are tremendously complex in their functioning and regulation. Studying the multifaceted behaviour and describing the performance of such complexity has challenged the scientific community for years. The reduction of real-world intricacy into simple descriptive models has therefore convinced many researchers of the usefulness of introducing mathematics into biological sciences. Predictive modelling takes such an approach another step further in that it takes advantage of existing knowledge to project the performance of a system in alternating scenarios. The ever growing amounts of available data generated by assessing biological systems at increasingly higher detail provide unique opportunities for future modelling and experiment design. Here we aim to provide an overview of the progress made in modelling over time and the currently prevalent approaches for iterative modelling cycles in modern biology. We will further argue for the importance of versatility in modelling approaches, including parameter estimation, model reduction and network reconstruction. Finally, we will discuss the difficulties in overcoming the mathematical interpretation of in vivo complexity and address some of the future challenges lying ahead. © 2013 John Wiley & Sons Ltd.

Power performance assessment. Final report

International Nuclear Information System (INIS)

Frandsen, S.

1998-12-01

In the increasingly commercialised wind power marketplace, the lack of precise assessment methods for the output of an investment is becoming a barrier for wider penetration of wind power. Thus, addressing this problem, the overall objectives of the project are to reduce the financial risk in investment in wind power projects by significantly improving the power performance assessment methods. Ultimately, if this objective is successfully met, the project may also result in improved tuning of the individual wind turbines and in optimisation methods for wind farm operation. The immediate, measurable objectives of the project are: To prepare a review of existing contractual aspects of power performance verification procedures of wind farms; to provide information on production sensitivity to specific terrain characteristics and wind turbine parameters by analyses of a larger number of wind farm power performance data available to the proposers; to improve the understanding of the physical parameters connected to power performance in complex environment by comparing real-life wind farm power performance data with 3D computational flow models and 3D-turbulence wind turbine models; to develop the statistical framework including uncertainty analysis for power performance assessment in complex environments; and to propose one or more procedures for power performance evaluation of wind power plants in complex environments to be applied in contractual agreements between purchasers and manufacturers on production warranties. Although the focus in this project is on power performance assessment the possible results will also be of benefit to energy yield forecasting, since the two tasks are strongly related. (au) JOULE III. 66 refs.; In Co-operation Renewable Energy System Ltd. (GB); Centre for Renewable Energy (GR); Aeronautic Research Centre (SE); National Engineering Lab. (GB); Public Power Cooperation (GR)

Thrive or overload? The effect of task complexity on novices' simulation-based learning.

Science.gov (United States)

Haji, Faizal A; Cheung, Jeffrey J H; Woods, Nicole; Regehr, Glenn; de Ribaupierre, Sandrine; Dubrowski, Adam

2016-09-01

Fidelity is widely viewed as an important element of simulation instructional design based on its purported relationship with transfer of learning. However, higher levels of fidelity may increase task complexity to a point at which novices' cognitive resources become overloaded. In this experiment, we investigate the effects of variations in task complexity on novices' cognitive load and learning during simulation-based procedural skills training. Thirty-eight medical students were randomly assigned to simulation training on a simple or complex lumbar puncture (LP) task. Participants completed four practice trials on this task (skill acquisition). After 10 days of rest, all participants completed one additional trial on their assigned task (retention) and one trial on a 'very complex' simulation designed to be similar to the complex task (transfer). We assessed LP performance and cognitive load on each trial using multiple measures. In both groups, LP performance improved significantly during skill acquisition (p ≤ 0.047, f = 0.29-0.96) and was maintained at retention. The simple task group demonstrated superior performance compared with the complex task group throughout these phases (p ≤ 0.002, d = 1.13-2.31). Cognitive load declined significantly in the simple task group (p Education.

A dedicated scholarly research program in an adult and pediatric neurology residency program.

Science.gov (United States)

Robbins, Matthew S; Haut, Sheryl R; Lipton, Richard B; Milstein, Mark J; Ocava, Lenore C; Ballaban-Gil, Karen; Moshé, Solomon L; Mehler, Mark F

2017-04-04

To describe and assess the effectiveness of a formal scholarly activity program for a highly integrated adult and pediatric neurology residency program. Starting in 2011, all graduating residents were required to complete at least one form of scholarly activity broadly defined to include peer-reviewed publications or presentations at scientific meetings of formally mentored projects. The scholarly activity program was administered by the associate residency training director and included an expanded journal club, guided mentorship, a required grand rounds platform presentation, and annual awards for the most scholarly and seminal research findings. We compared scholarly output and mentorship for residents graduating within a 5-year period following program initiation (2011-2015) and during the preceding 5-year preprogram baseline period (2005-2009). Participation in scholarship increased from the preprogram baseline (24 of 53 graduating residents, 45.3%) to the postprogram period (47 of 57 graduating residents, 82.1%, p Neurology.

Relationships between the handball-specific complex test, non-specific field tests and the match performance score in elite professional handball players.

Science.gov (United States)

Hermassi, Souhail; Chelly, Mohamed-Souhaiel; Wollny, Rainer; Hoffmeyer, Birgit; Fieseler, Georg; Schulze, Stephan; Irlenbusch, Lars; Delank, Karl-Stefan; Shephard, Roy J; Bartels, Thomas; Schwesig, René

2018-06-01

This study assessed the validity of the handball-specific complex test (HBCT) and two non-specific field tests in professional elite handball athletes, using the match performance score (MPS) as the gold standard of performance. Thirteen elite male handball players (age: 27.4±4.8 years; premier German league) performed the HBCT, the Yo-Yo Intermittent Recovery (YYIR) test and a repeated shuttle sprint ability (RSA) test at the beginning of pre-season training. The RSA results were evaluated in terms of best time, total time, and fatigue decrement. Heart rates (HR) were assessed at selected times throughout all tests; the recovery HR was measured immediately post-test and 10 minutes later. The match performance score was based on various handball specific parameters (e.g., field goals, assists, steals, blocks, and technical mistakes) as seen during all matches of the immediately subsequent season (2015/2016). The parameters of run 1, run 2, and HR recovery at minutes 6 and 10 of the RSA test all showed a variance of more than 10% (range: 11-15%). However, the variance of scores for the YYIR test was much smaller (range: 1-7%). The resting HR (r2=0.18), HR recovery at minute 10 (r2=0.10), lactate concentration at rest (r2=0.17), recovery of heart rate from 0 to 10 minutes (r2=0.15), and velocity of second throw at first trial (r2=0.37) were the most valid HBCT parameters. Much effort is necessary to assess MPS and to develop valid tests. Speed and the rate of functional recovery seem the best predictors of competitive performance for elite handball players.

Allergen-containing immune complexes used for immunotherapy of allergic asthma. Preparation of complexes and evaluation of their clinical performance in guinea pigs

DEFF Research Database (Denmark)

Poulsen, L K; Lundberg, L; Søndergaard, I

1989-01-01

Guinea pigs inbred for their ability to develop respiratory anaphylaxis to experimental antigens have been used for comparison of different forms of immunotherapy (IT). Passive, active and combined (immune complexes between antigen and specific IgG) IT were compared with placebo. The bronchial re...... groups surprisingly recovered their original sensitivity to inhalation of the antigen....

The Complexity of Mitochondrial Complex IV: An Update of Cytochrome c Oxidase Biogenesis in Plants

Science.gov (United States)

Mansilla, Natanael; Racca, Sofia; Gras, Diana E.; Gonzalez, Daniel H.

2018-01-01

Mitochondrial respiration is an energy producing process that involves the coordinated action of several protein complexes embedded in the inner membrane to finally produce ATP. Complex IV or Cytochrome c Oxidase (COX) is the last electron acceptor of the respiratory chain, involved in the reduction of O2 to H2O. COX is a multimeric complex formed by multiple structural subunits encoded in two different genomes, prosthetic groups (heme a and heme a3), and metallic centers (CuA and CuB). Tens of accessory proteins are required for mitochondrial RNA processing, synthesis and delivery of prosthetic groups and metallic centers, and for the final assembly of subunits to build a functional complex. In this review, we perform a comparative analysis of COX composition and biogenesis factors in yeast, mammals and plants. We also describe possible external and internal factors controlling the expression of structural proteins and assembly factors at the transcriptional and post-translational levels, and the effect of deficiencies in different steps of COX biogenesis to infer the role of COX in different aspects of plant development. We conclude that COX assembly in plants has conserved and specific features, probably due to the incorporation of a different set of subunits during evolution. PMID:29495437

Mixed-ligand Al complex-a new approach for more high efficient OLEDs

Energy Technology Data Exchange (ETDEWEB)

Petrova, Petia K., E-mail: petia@clf.bas.bg [Institute of Optical Materials and Technologies ' Acad. J. Malinowski' , Bulgarian Academy of Sciences, Acad. G Bonchev st., bl. 109, 1113 Sofia (Bulgaria); Tomova, Reni L.; Stoycheva-Topalova, Rumiana T. [Institute of Optical Materials and Technologies ' Acad. J. Malinowski' , Bulgarian Academy of Sciences, Acad. G Bonchev st., bl. 109, 1113 Sofia (Bulgaria); Kaloyanova, Stefka S.; Deligeorgiev, Todor G. [Applied Organic Chemistry, Faculty of Chemistry, University of Sofia, Sofia 1164 (Bulgaria)

2012-02-15

The mixed-ligand Aluminum bis(8-hydroxyquinoline) acetylacetonate (Alq{sub 2}Acac) complex was presented and its performance as electroluminescent and electron transporting layer for OLED was studied. The photophysical properties of the novel complex were investigated and compared with the properties of the parent Alq{sub 3}. Highly efficient OLED based on the mixed-ligand Al complex was developed with two times higher luminescence and efficiency compared to the identical OLED based on the conventional Alq{sub 3} The better performance of the devices make the novel Al complex a very promising material for OLEDs. - Highlights: Black-Right-Pointing-Pointer A novel electroluminescent Alq{sub 2}Acac complex is presented as material for OLED. Black-Right-Pointing-Pointer Electroluminescent emission of Alq{sub 2}Acac is very similar to that of commercial Alq{sub 3}. Black-Right-Pointing-Pointer Devices with Alq{sub 2}Acac show better characteristics compared to those with Alq{sub 3}.

NetProt: Complex-based Feature Selection.

Science.gov (United States)

Goh, Wilson Wen Bin; Wong, Limsoon

2017-08-04

Protein complex-based feature selection (PCBFS) provides unparalleled reproducibility with high phenotypic relevance on proteomics data. Currently, there are five PCBFS paradigms, but not all representative methods have been implemented or made readily available. To allow general users to take advantage of these methods, we developed the R-package NetProt, which provides implementations of representative feature-selection methods. NetProt also provides methods for generating simulated differential data and generating pseudocomplexes for complex-based performance benchmarking. The NetProt open source R package is available for download from https://github.com/gohwils/NetProt/releases/ , and online documentation is available at http://rpubs.com/gohwils/204259 .

Detection of protein complex from protein-protein interaction network using Markov clustering

International Nuclear Information System (INIS)

Ochieng, P J; Kusuma, W A; Haryanto, T

2017-01-01

Detection of complexes, or groups of functionally related proteins, is an important challenge while analysing biological networks. However, existing algorithms to identify protein complexes are insufficient when applied to dense networks of experimentally derived interaction data. Therefore, we introduced a graph clustering method based on Markov clustering algorithm to identify protein complex within highly interconnected protein-protein interaction networks. Protein-protein interaction network was first constructed to develop geometrical network, the network was then partitioned using Markov clustering to detect protein complexes. The interest of the proposed method was illustrated by its application to Human Proteins associated to type II diabetes mellitus. Flow simulation of MCL algorithm was initially performed and topological properties of the resultant network were analysed for detection of the protein complex. The results indicated the proposed method successfully detect an overall of 34 complexes with 11 complexes consisting of overlapping modules and 20 non-overlapping modules. The major complex consisted of 102 proteins and 521 interactions with cluster modularity and density of 0.745 and 0.101 respectively. The comparison analysis revealed MCL out perform AP, MCODE and SCPS algorithms with high clustering coefficient (0.751) network density and modularity index (0.630). This demonstrated MCL was the most reliable and efficient graph clustering algorithm for detection of protein complexes from PPI networks. (paper)

How Complex Do Movie Channel Contracts Need to Be?

OpenAIRE

Sumit Raut; Sanjeev Swami; Eunkyu Lee; Charles B. Weinberg

2008-01-01

The motion picture industry is characterized by a dynamic market environment, limited shelf space and product category management, and consequently, complex channel contracts specifying the split of box office revenue between distributors and exhibitors. Although such a contracting practice creates a considerable administrative effort and channel conflict, it is not clear whether such complexity is necessary for superior channel performance. This study investigates this question by analyzing ...

Fabrication of Tiron-TiO{sub 2} charge-transfer complex with excellent visible-light photocatalytic performance

Energy Technology Data Exchange (ETDEWEB)

Yao, Binghua, E-mail: bhyao@xaut.edu.cn [Department of Applied Chemistry, Xi' an University of Technology, Xi' an 710048 (China); The Key Laboratory of Northwest Water Resources and Environmental Ecology of Ministry of Education, Xi' an University of Technology, Xi' an 710048 (China); Peng, Chao; Lu, Pan; He, Yangqing [Department of Applied Chemistry, Xi' an University of Technology, Xi' an 710048 (China); Zhang, Wen, E-mail: wenzhang@uark.edu [Department of Civil Engineering, University of Arkansas, Fayetteville 72701 (United States); Zhang, Qinku [Department of Applied Chemistry, Xi' an University of Technology, Xi' an 710048 (China); The Key Laboratory of Northwest Water Resources and Environmental Ecology of Ministry of Education, Xi' an University of Technology, Xi' an 710048 (China)

2016-12-01

A new charge-transfer(CT) complex (Tiron-TiO{sub 2}) was prepared via the 1,2-dihydroxy-3,5-benzenedisulfonic acid disodium salt (Tiron) as chelate sensitizer. The phase structures and morphologies were measured by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results demonstrated that the as-prepared Tiron-TiO{sub 2} is of anatase microspheres with size range between 300 and 350 nm. The analysis of FT-IR and XPS revealed that the binding structure of the Tiron-TiO{sub 2} CT complex is of the characteristic of bidentate binuclear binding-bridging. UV–vis analysis showed that the formation of CT complex on the surface of TiO{sub 2} through Tiron significantly extends the photoresponse of Tiron-TiO{sub 2} nanoparticles to visible light range (400–600 nm). Compared with unmodified TiO{sub 2}, Tiron-modified TiO{sub 2}(Tiron-TiO{sub 2}) exhibited excellent photocatalytic activity for the photocatalytic degradation of methylene blue(MB) and three kind of antibiotics under visible light irradiation (λ > 400 nm). - Highlights: • The Tiron-TiO{sub 2} charge transfer complex was synthesized. • The incorporation of Tiron with TiO{sub 2} extended TiO{sub 2} response to visible light region. • Tiron-TiO{sub 2} exhibited significant photocatalytic degradation for antibiotics. • Tiron-TiO{sub 2} showed the long-term stability and reusability.

Complex multimaterial insulating frames for windows with evacuated glazing

Energy Technology Data Exchange (ETDEWEB)

Fang, Yueping; Eames, Philip C.; Hyde, Trevor J. [Centre for Sustainable Technologies, School of the Built Environment, University of Ulster, Newtownabbey, N. Ireland BT37 0QB (United Kingdom); Norton, Brian [Dublin Institute of Technology, Aungier Street, Dublin 2 (Ireland)

2005-09-01

The thermal performance of a complex multimaterial frame consisting of an exoskeleton framework and cavities filled with insulant materials enclosing an evacuated glazing was simulated using a two-dimensional finite element model and the results were validated experimentally using a guarded hot box calorimeter. The analysed 0.5m by 0.5m evacuated glazing consisted of two low-emittance film coated glass panes supported by an array of 0.32mm diameter pillars spaced 25mm apart, contiguously sealed by a 10mm wide metal edge seal. Thermal performance of windows employing evacuated glazing set in various complex multimaterial frames were analysed in detail. Very good agreement was found between simulations and experimental measurements of surface temperatures of the evacuated glazing window system. The heat loss from a window with an evacuated glazing and a complex multimaterial frame is about 80% of that for a window comprised of an evacuated glazing set in a single material solid frame. (author)

Complex multimaterial insulating frames for windows with evacuated glazing

Energy Technology Data Exchange (ETDEWEB)

Yueping Fang; Eames, P.C.; Hyde, T.J. [University of Ulster, Newtonabbey (United Kingdom). Centre for Sustainable Technologies; Norton, B. [Dublin Institute of Technology, Dublin (Ireland)

2005-09-01

The thermal performance of a complex multimaterial frame consisting of an exoskeleton framework and cavities filled with insulant materials enclosing an evacuated glazing was simulated using a two-dimensional finite element model and the results were validated experimentally using a guarded hot box calorimeter. The analysed 0.5 m by 0.5 m evacuated glazing consisted of two low-emittance film coated glass panes supported by an array of 0.32 mm diameter pillars spaced 25 mm apart, contiguously sealed by a 10 mm wide metal edge seal. Thermal performance of windows employing evacuated glazing set in various complex multimaterial frames were analysed in detail. Very good agreement was found between simulations and experimental measurements of surface temperatures of the evacuated glazing window system. The heat loss from a window with an evacuated glazing and a complex multimaterial frame is about 80% of that for a window comprised of an evacuated glazing set in a single material solid frame. (author)

Low-complexity R-peak detection for ambulatory fetal monitoring

International Nuclear Information System (INIS)

Rooijakkers, Michael J; Rabotti, Chiara; Mischi, Massimo; Oei, S Guid

2012-01-01

Non-invasive fetal health monitoring during pregnancy is becoming increasingly important because of the increasing number of high-risk pregnancies. Despite recent advances in signal-processing technology, which have enabled fetal monitoring during pregnancy using abdominal electrocardiogram (ECG) recordings, ubiquitous fetal health monitoring is still unfeasible due to the computational complexity of noise-robust solutions. In this paper, an ECG R-peak detection algorithm for ambulatory R-peak detection is proposed, as part of a fetal ECG detection algorithm. The proposed algorithm is optimized to reduce computational complexity, without reducing the R-peak detection performance compared to the existing R-peak detection schemes. Validation of the algorithm is performed on three manually annotated datasets. With a detection error rate of 0.23%, 1.32% and 9.42% on the MIT/BIH Arrhythmia and in-house maternal and fetal databases, respectively, the detection rate of the proposed algorithm is comparable to the best state-of-the-art algorithms, at a reduced computational complexity. (paper)

Low-complexity R-peak detection for ambulatory fetal monitoring.

Science.gov (United States)

Rooijakkers, Michael J; Rabotti, Chiara; Oei, S Guid; Mischi, Massimo

2012-07-01

Non-invasive fetal health monitoring during pregnancy is becoming increasingly important because of the increasing number of high-risk pregnancies. Despite recent advances in signal-processing technology, which have enabled fetal monitoring during pregnancy using abdominal electrocardiogram (ECG) recordings, ubiquitous fetal health monitoring is still unfeasible due to the computational complexity of noise-robust solutions. In this paper, an ECG R-peak detection algorithm for ambulatory R-peak detection is proposed, as part of a fetal ECG detection algorithm. The proposed algorithm is optimized to reduce computational complexity, without reducing the R-peak detection performance compared to the existing R-peak detection schemes. Validation of the algorithm is performed on three manually annotated datasets. With a detection error rate of 0.23%, 1.32% and 9.42% on the MIT/BIH Arrhythmia and in-house maternal and fetal databases, respectively, the detection rate of the proposed algorithm is comparable to the best state-of-the-art algorithms, at a reduced computational complexity.

A cross-sectional retrospective analysis of the regionalization of complex surgery.

Science.gov (United States)

Studnicki, James; Craver, Christopher; Blanchette, Christopher M; Fisher, John W; Shahbazi, Sara

2014-08-16

The Veterans Health Administration (VHA) system has assigned a surgical complexity level to each of its medical centers by specifying requirements to perform standard, intermediate or complex surgical procedures. No study to similarly describe the patterns of relative surgical complexity among a population of United States (U.S) civilian hospitals has been completed. single year, retrospective, cross-sectional. the study used Florida Inpatient Discharge Data from short-term acute hospitals for calendar year 2009. Two hundred hospitals with 2,542,920 discharges were organized into four quartiles (Q 1, 2, 3, 4) based on the number of complex procedures per hospital. The VHA surgical complexity matrix was applied to assign relative complexity to each procedure. The Clinical Classification Software (CCS) system assigned complex procedures to clinically meaningful groups. For outcome comparisons, propensity score matching methods adjusted for the surgical procedure, age, gender, race, comorbidities, mechanical ventilator use and type of admission. in-hospital mortality and length-of-stay (LOS). Only 5.2% of all inpatient discharges involve a complex procedure. The highest volume complex procedure hospitals (Q4) have 49.8% of all discharges but 70.1% of all complex procedures. In the 133,436 discharges with a primary complex procedure, 374 separate specific procedures are identified, only about one third of which are performed in the lowest volume complex procedure (Q1) hospitals. Complex operations of the digestive, respiratory, integumentary and musculoskeletal systems are the least concentrated and proportionately more likely to occur in the lower volume hospitals. Operations of the cardiovascular system and certain technology dependent miscellaneous diagnostic and therapeutic procedures are the most concentrated in high volume hospitals. Organ transplants are only done in Q4 hospitals. There were no significant differences in in-hospital mortality rates and the

Luminescent zinc(ii) and copper(i) complexes for high-performance solution-processed monochromic and white organic light-emitting devices.

Science.gov (United States)

Cheng, Gang; So, Gary Kwok-Ming; To, Wai-Pong; Chen, Yong; Kwok, Chi-Chung; Ma, Chensheng; Guan, Xiangguo; Chang, Xiaoyong; Kwok, Wai-Ming; Che, Chi-Ming

2015-08-01

The synthesis and spectroscopic properties of luminescent tetranuclear zinc(ii) complexes of substituted 7-azaindoles and a series of luminescent copper(i) complexes containing 7,8-bis(diphenylphosphino)-7,8-dicarba- nido -undecaborate ligand are described. These complexes are stable towards air and moisture. Thin film samples of the luminescent copper(i) complexes in 2,6-dicarbazolo-1,5-pyridine and zinc(ii) complexes in poly(methyl methacrylate) showed emission quantum yields of up to 0.60 (for Cu-3 ) and 0.96 (for Zn-1 ), respectively. Their photophysical properties were examined by ultrafast time-resolved emission spectroscopy, temperature dependent emission lifetime measurements and density functional theory calculations. Monochromic blue and orange solution-processed OLEDs with these Zn(ii) and Cu(i) complexes as light-emitting dopants have been fabricated, respectively. Maximum external quantum efficiency (EQE) of 5.55% and Commission Internationale de l'Eclairage (CIE) coordinates of (0.16, 0.19) were accomplished with the optimized Zn-1 -OLED while these values were, respectively 15.64% and (0.48, 0.51) for the optimized Cu-3 -OLED. Solution-processed white OLEDs having maximum EQE of 6.88%, CIE coordinates of (0.42, 0.44), and colour rendering index of 81 were fabricated by using these luminescent Zn(ii) and Cu(i) complexes as blue and orange light-emitting dopant materials, respectively.

TFTR plasma feedback systems

International Nuclear Information System (INIS)

Efthimion, P.; Hawryluk, R.J.; Hojsak, W.; Marsala, R.J.; Mueller, D.; Rauch, W.; Tait, G.D.; Taylor, G.; Thompson, M.

1985-01-01

The Tokamak Fusion Test Reactor employs feedback control systems for four plasma parameters, i.e. for plasma current, for plasma major radius, for plasma vertical position, and for plasma density. The plasma current is controlled by adjusting the rate of change of current in the Ohmic Heating (OH) coil system. Plasma current is continuously sensed by a Rogowski coil and its associated electronics; the error between it and a preprogrammed reference plasma current history is operated upon by a ''proportional-plusintegral-plus-derivative'' (PID) control algorithm and combined with various feedforward terms, to generate compensating commands to the phase-controlled thyristor rectifiers which drive current through the OH coils. The plasma position is controlled by adjusting the currents in Equilibrium Field and Horizontal Field coil systems, which respectively determine the vertical and radial external magnetic fields producing J X B forces on the plasma current. The plasma major radius position and vertical position, sensed by ''B /sub theta/ '' and ''B /sub rho/ '' magnetic flux pickup coils with their associated electronics, are controlled toward preprogrammed reference histories by allowing PID and feedforward control algorithms to generate commands to the EF and HF coil power supplies. Plasma density is controlled by adjusting the amount of gas injected into the vacuum vessel. Time-varying gains are used to combine lineaveraged plasma density measurements from a microwave interferometer plasma diagnostic system with vacuum vessel pressure measurements from ion gauges, with various other measurements, and with preprogrammed reference histories, to determine commands to piezoelectric gas injection valves

Facile fabrication of uniaxial nanopatterns on shape memory polymer substrates using a complete bottom-up approach

Science.gov (United States)

Chen, Zhongbi; Krishnaswamy, Sridhar

2014-03-01

In earlier work, we have demonstrated an assisted self-assembly fabrication method for unidirectional submicron patterns using pre-programmed shape memory polymers (SMP) as the substrate in an organic/inorganic bilayer structure. In this paper, we propose a complete bottom-up method for fabrication of uniaxial wrinkles whose wavelength is below 300 nm. The method starts with using the aforementioned self-assembled bi-layer wrinkled surface as the template to make a replica of surface wrinkles on a PDMS layer which is spin-coated on a pre-programmed SMP substrate. When the shape recovery of the substrate is triggered by heating it to its transition temperature, the substrate has been programmed in such a way that it shrinks uniaxially to return to its permanent shape. Consequently, the wrinkle wavelength on PDMS reduces accordingly. A subsequent contact molding process is carried out on the PDMS layer spin-coated on another pre-programmed SMP substrate, but using the wrinkled PDMS surface obtained in the previous step as the master. By activating the shape recovery of the substrate, the wrinkle wavelength is further reduced a second time in a similar fashion. Our experiments showed that the starting wavelength of 640 nm decreased to 290 nm after two cycles of recursive molding. We discuss the advantages and limitations of our recursive molding approach compared to the prevalent top-down fabrication methods represented by lithography. The present study is expected to o er a simple and cost-e ective fabrication method of nano-scale uniaxial wrinkle patterns with the potential for large-scale mass-production.

Anion-π aromatic neutral tweezers complexes: are they stable in polar solvents?

Science.gov (United States)

Sánchez-Lozano, Marta; Otero, Nicolás; Hermida-Ramón, Jose M; Estévez, Carlos M; Mandado, Marcos

2011-03-17

The impact of the solvent environment on the stabilization of the complexes formed by fluorine (T-F) and cyanide (T-CN) substituted tweezers with halide anions has been investigated theoretically. The study was carried out using computational methodologies based on density functional theory (DFT) and symmetry adapted perturbation theory (SAPT). Interaction energies were obtained at the M05-2X/6-31+G* level. The obtained results show a large stability of the complexes in solvents with large dielectric constant and prove the suitability of these molecular tweezers as potential hosts for anion recognition in solution. A detailed analysis of the effects of the solvent on the electron withdrawing ability of the substituents and its influence on the complex stability has been performed. In particular, the interaction energy in solution was split up into intermonomer and solvent-complex terms. In turn, the intermonomer interaction energy was partitioned into electrostatic, exchange, and polarization terms. Polar resonance structures in T-CN complexes are favored by polar solvents, giving rise to a stabilization of the intermonomer interaction, the opposite is found for T-F complexes. The solvent-complex energy increases with the polarity of the solvent in T-CN complexes, nonetheless the energy reaches a maximum and then decreases slowly in T-F complexes. An electron density analysis was also performed before and after complexation, providing an explanation to the trends followed by the interaction energies and their different components in solution.

Characterization of pioglitazone cyclodextrin complexes: Molecular modeling to in vivo evaluation

Directory of Open Access Journals (Sweden)

Dinesh M Bramhane

2016-01-01

Full Text Available Aims: The objective of present study was to study the influence of different β-cyclodextrin derivatives and different methods of complexation on aqueous solubility and consequent translation in in vivo performance of Pioglitazone (PE. Material and Methods: Three cyclodextrins: β-cyclodextrin (BCD, hydroxypropyl-β-cyclodextrin (HPBCD and Sulfobutylether-7-β-cyclodextrin (SBEBCD were employed in preparation of 1:1 Pioglitazone complexes by three methods viz. co-grinding, kneading and co-evaporation. Complexation was confirmed by phase solubility, proton NMR, Fourier Transform Infrared spectroscopy, Differential Scanning Calorimetry (DSC and X-Ray diffraction (XRD. Mode of complexation was investigated by molecular dynamic studies. Pharmacodynamic study of blood glucose lowering activity of PE complexes was performed in Alloxan induced diabetic rat model. Results: Aqueous solubility of PE was significantly improved in presence of cyclodextrin. Apparent solubility constants were observed to be 254.33 M–1 for BCD-PE, 737.48 M–1 for HPBCD-PE and 5959.06 M–1 for SBEBCD-PE. The in silico predictions of mode of inclusion were in close agreement with the experimental proton NMR observation. DSC and XRD demonstrated complete amorphization of crystalline PE upon inclusion. All complexes exhibited >95% dissolution within 10 min compared to drug powder that showed <40% at the same time. Marked lowering of blood glucose was recorded for all complexes. Conclusion: Complexation of PE with different BCD significantly influenced its aqueous solubility, improved in vitro dissolution and consequently translated into enhanced pharmacodynamic activity in rats

Performance analysis and prediction in triathlon.

Science.gov (United States)

Ofoghi, Bahadorreza; Zeleznikow, John; Macmahon, Clare; Rehula, Jan; Dwyer, Dan B

2016-01-01

Performance in triathlon is dependent upon factors that include somatotype, physiological capacity, technical proficiency and race strategy. Given the multidisciplinary nature of triathlon and the interaction between each of the three race components, the identification of target split times that can be used to inform the design of training plans and race pacing strategies is a complex task. The present study uses machine learning techniques to analyse a large database of performances in Olympic distance triathlons (2008-2012). The analysis reveals patterns of performance in five components of triathlon (three race "legs" and two transitions) and the complex relationships between performance in each component and overall performance in a race. The results provide three perspectives on the relationship between performance in each component of triathlon and the final placing in a race. These perspectives allow the identification of target split times that are required to achieve a certain final place in a race and the opportunity to make evidence-based decisions about race tactics in order to optimise performance.

Switching Performance Evaluation of Commercial SiC Power Devices (SiC JFET and SiC MOSFET) in Relation to the Gate Driver Complexity

DEFF Research Database (Denmark)

Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.

2013-01-01

and JFETs. The recent introduction of SiC MOSFET has proved that it is possible to have highly performing SiC devices with a minimum gate driver complexity; this made SiC power devices even more attractive despite their device cost. This paper presents an analysis based on experimental results...... of the switching losses of various commercially available Si and SiC power devices rated at 1200 V (Si IGBTs, SiC JFETs and SiC MOSFETs). The comparison evaluates the reduction of the switching losses which is achievable with the introduction of SiC power devices; this includes analysis and considerations...

Improvement an enterprises marketing performance measurement system

Directory of Open Access Journals (Sweden)

Stanković Ljiljana

2013-01-01

Full Text Available Business conditions in which modern enterprises do business are more and more complex. The complexity of the business environment is caused by activities of external and internal factors, which imposes the need for the turn in management focus. One of key turns is related to the need of adaptation and development of new business performance evaluation systems. The evaluation of marketing contribution to business performance is very important however a complex task as well. The marketing theory and practice indicates the need for developing adequate standards and systems for evaluating the efficiency of marketing decisions. The better understanding of marketing standards and ways that managers use is a very important factor that affects the efficiency of strategic decision-making. The paper presents the results of researching the way in which managers perceive and apply marketing performance measures. The data that were received through the field research sample enabled the consideration of the managers' attitudes on practical ways of implementing marketing performance measurement and identifying measures that managers imply as used mostly in business practice.

The forearm complex: anatomy, biomechanics and clinical considerations.

Science.gov (United States)

LaStayo, Paul C; Lee, Michael J

2006-01-01

The forearm complex is comprised of the proximal radioulnar joint, middle radioulnar joint/interosseous membrane, and the distal radioulnar joint. These three areas function in a coordinated manner to rotate the hand in space and allow performance of functional tasks. If a structure or structures in one of these three areas is disrupted, this can adversely affect the function at any of the other two remaining areas. Surgical intervention focuses on restoring anatomical alignment to preserve the function of the forearm complex. Rehabilitation is guided by the relationships between the three areas of the forearm complex and the awareness of clinical signs, symptoms, and complications. The purposes of this paper are to 1) describe the anatomy and biomechanical function of the forearm complex and 2) discuss clinical correlates pertaining to select forearm injuries (excluding peripheral nerve injuries) that may affect forearm function.

A low-complexity interacting multiple model filter for maneuvering target tracking

KAUST Repository

Khalid, Syed Safwan; Abrar, Shafayat

2017-01-01

In this work, we address the target tracking problem for a coordinate-decoupled Markovian jump-mean-acceleration based maneuvering mobility model. A novel low-complexity alternative to the conventional interacting multiple model (IMM) filter is proposed for this class of mobility models. The proposed tracking algorithm utilizes a bank of interacting filters where the interactions are limited to the mixing of the mean estimates, and it exploits a fixed off-line computed Kalman gain matrix for the entire filter bank. Consequently, the proposed filter does not require matrix inversions during on-line operation which significantly reduces its complexity. Simulation results show that the performance of the low-complexity proposed scheme remains comparable to that of the traditional (highly-complex) IMM filter. Furthermore, we derive analytical expressions that iteratively evaluate the transient and steady-state performance of the proposed scheme, and establish the conditions that ensure the stability of the proposed filter. The analytical findings are in close accordance with the simulated results.

A low-complexity interacting multiple model filter for maneuvering target tracking

KAUST Repository

Khalid, Syed Safwan

2017-01-22

In this work, we address the target tracking problem for a coordinate-decoupled Markovian jump-mean-acceleration based maneuvering mobility model. A novel low-complexity alternative to the conventional interacting multiple model (IMM) filter is proposed for this class of mobility models. The proposed tracking algorithm utilizes a bank of interacting filters where the interactions are limited to the mixing of the mean estimates, and it exploits a fixed off-line computed Kalman gain matrix for the entire filter bank. Consequently, the proposed filter does not require matrix inversions during on-line operation which significantly reduces its complexity. Simulation results show that the performance of the low-complexity proposed scheme remains comparable to that of the traditional (highly-complex) IMM filter. Furthermore, we derive analytical expressions that iteratively evaluate the transient and steady-state performance of the proposed scheme, and establish the conditions that ensure the stability of the proposed filter. The analytical findings are in close accordance with the simulated results.

On the complex analysis of the reliability, safety, and economic efficiency of atomic electric power stations

International Nuclear Information System (INIS)

Emel'yanov, I.Ya.; Klemin, A.I.; Polyakov, E.F.

1977-01-01

The problem is posed of effectively increasing the engineering performance of nuclear electric power stations (APS). The principal components of the engineering performance of modern large APS are considered: economic efficiency, radiation safety, reliability, and their interrelationship. A nomenclature is proposed for the quantitative indices which most completely characterize the enumerated properties and are convenient for the analysis of the engineering performance. The urgent problem of developing a methodology for the complex analysis and optimization of the principal performance components is considered; this methodology is designed to increase the efficiency of the work on high-performance competitive APS. The principle of complex optimization of the reliability, safety, and economic-efficiency indices is formulated; specific recommendations are made for the practical realization of this principle. The structure of the complex quantiative analysis of the enumerated performance components is given. The urgency and promise of the complex approach to solving the problem of APS optimization is demonstrated, i.e., the solution of the problem of creating optimally reliable, fairly safe, and maximally economically efficient stations

Electrodermal complexity during the Stroop colour word test.

Science.gov (United States)

Svetlak, Miroslav; Bob, Petr; Cernik, Michal; Kukleta, Miloslav

2010-01-15

Several recent studies suggest that quantitative description of signal complexity using algorithms of nonlinear analysis could uncover new information about the autonomic system that is not reflected using common methods applied to measures of autonomic activity. With this aim we have performed complexity analysis of electrodermal activity (EDA) assessed in 106 healthy university students during rest conditions and non-conflicting and conflicting Stroop task. Complexity analysis applied to EDA was performed using Skinner's algorithm for pointwise correlation dimension (PD2). Results have shown that EDA responses during the Stroop Colour Word test are related to significantly increased or decreased complexity. Particularly significant result is that PD2 has a unique ability to predict to an extent the change in EDA response to stress i.e. that subjects with low initial PD2 tended to respond to experimental stress by its increase and subjects with high initial PD2 values tended to respond by its decrease. This response was not found in EDA measures where increase of the EDA presented predominant response to experimental stress in majority of the subjects. These findings suggest that PD2 is more sensitive to subtle aspects of functionally and spatially distributed modulatory influences of various parts of the brain that are involved in the EDA modulation and provides novel information in comparison to traditional methods.

Variability and Variation in Second Language Acquisition Orders : A Dynamic Reevaluation

NARCIS (Netherlands)

Lowie, Wander; Verspoor, Marjolijn

2015-01-01

The traditional morpheme order studies in second language acquisition have tried to demonstrate the existence of a fixed order of acquisition of English morphemes, regardless of the second language learner's background. Such orders have been taken as evidence of the preprogrammed nature of language

The Influence of Advertising on Attendance at Park Programs

Science.gov (United States)

Reyburn, Jerry H.; Knudson, Douglas M.

1975-01-01

Investigated were the effects on attendance of four types of pre-program advertising: no advertising, personal invitation, signs, and innovation. All three advertising treatments increased program attendance over no advertising. Each advertising technique has advantages and disadvantages. Signs are impersonal, but effective. Personal invitation is…

76 FR 186 - Notice of Buy American Waiver Under the American Recovery and Reinvestment Act of 2009

Science.gov (United States)

2011-01-03

... system set-up. 8. Pre-programmed with 150 channels for the existing facsimile stations world-wide and... successful operation world-wide. Eighteen (18) potential vendors were identified with only six (6... NATIONAL SCIENCE FOUNDATION Notice of Buy American Waiver Under the American Recovery and...

Electrolytic formation of technetium complexes with π-acceptor ligands

International Nuclear Information System (INIS)

Cerda, F.; Kremer, C.; Gambino, D.; Kremer, E.

1994-01-01

Electrolytic reduction of pertechnetate was performed in aqueous solution containing π-acceptor ligands. Cyanide and 1,10-phenanthroline were the selected ligands. In both cases, electrolyses produced a cathodic TcO 2 deposit and soluble Tc complexes. When cyanide was the ligand, the complexes formed were [Tc(CN) 6 ] 5- and [TcO 2 (CN) 4 ] 3- . When working with the amine, [Tc(phen) 3 ] 2+ and another positively charged species were found after reaction. Results are compared with previous studies with amines, and the usefulness of the electrolytic route to obtain Tc complexes is evaluated. (author) 11 refs.; 2 figs.; 1 tab

Entanglement entropy and complexity for one-dimensional holographic superconductors

Science.gov (United States)

Kord Zangeneh, Mahdi; Ong, Yen Chin; Wang, Bin

2017-08-01

Holographic superconductor is an important arena for holography, as it allows concrete calculations to further understand the dictionary between bulk physics and boundary physics. An important quantity of recent interest is the holographic complexity. Conflicting claims had been made in the literature concerning the behavior of holographic complexity during phase transition. We clarify this issue by performing a numerical study on one-dimensional holographic superconductor. Our investigation shows that holographic complexity does not behave in the same way as holographic entanglement entropy. Nevertheless, the universal terms of both quantities are finite and reflect the phase transition at the same critical temperature.

Complex diffusion process for noise reduction

DEFF Research Database (Denmark)

Nadernejad, Ehsan; Barari, A.

2014-01-01

equations (PDEs) in image restoration and de-noising prompted many researchers to search for an improvement in the technique. In this paper, a new method is presented for signal de-noising, based on PDEs and Schrodinger equations, named as complex diffusion process (CDP). This method assumes that variations...... for signal de-noising. To evaluate the performance of the proposed method, a number of experiments have been performed using Sinusoid, multi-component and FM signals cluttered with noise. The results indicate that the proposed method outperforms the approaches for signal de-noising known in prior art....

Magnetic resonance imaging in complex partial seizures

International Nuclear Information System (INIS)

Furune, Sunao; Negoro, Tamiko; Maehara, Mitsuo; Nomura, Kazushi; Miura, Kiyokuni; Takahashi, Izumi; Watanabe, Kazuyoshi

1989-01-01

Magnetic resonance imaging (MRI) and computed tomography (CT) were performed on 45 patients with intractable complex partial seizures. MRI was performed with a superconducting whole-body scanner operating at 0.5 tesla (T) and 1.5 T. In patients with temporal lobe epilepsy, 8 of 24 patients had abnormal CT, but 16 or 24 patients showed abnormal MRI. 1.5 T MRI detected more abnormality than 0.5 T MRI when CT was normal. In patients with frontal lobe epilepsy, 5 of 7 patients had normal CT and MRI. In 2 other patients, MRI demonstrated an arachnoid cyst and increased signal intensity area on the T2-weighted images which were not detected by CT. In patients with occipital lobe epilepsy, 5 of 6 patients show abnormal CT and MRI. In patients with tuberous sclerosis, MRI revealed some increased signal intensity areas on the T2-weighted images in the occipital and temporal lobe, which were not detected by CT. Most surface EEG foci corresponded with the side of MRI abnormality. These data indicate that MRI is more informative than CT in complex partial seizures. MRI is the imaging technique of choice in the diagnosis of complex partial seizures. (author)

THE ROLE OF PERFORMANCE APPRAISAL IN THE CONTEXT OF PERFORMANCE MANAGEMENT SYSTEMS

Directory of Open Access Journals (Sweden)

Maria HERMEL-STĂNESCU

2015-04-01

Full Text Available Performance management is a complex concept that integrates all business activities and creates a continuous system for improvement. One of the key ingredients in an efficient performance management system is a well-designed performance appraisal that integrates the individual goals with the team and organization goals. When designing a performance appraisal system one has to consider the many existing techniques, tools and sources of error. Also, when defining the expected results and KPI’s for measurement, it is important to know the difference between output and outcome. The present paper aims to synthetize, through a literature review, the main aspects of performance appraisal in the context of performance management, pointing out its advantages and disadvantages.

Predictive performance models and multiple task performance

Science.gov (United States)

Wickens, Christopher D.; Larish, Inge; Contorer, Aaron

1989-01-01

Five models that predict how performance of multiple tasks will interact in complex task scenarios are discussed. The models are shown in terms of the assumptions they make about human operator divided attention. The different assumptions about attention are then empirically validated in a multitask helicopter flight simulation. It is concluded from this simulation that the most important assumption relates to the coding of demand level of different component tasks.

High-performance-vehicle technology. [fighter aircraft propulsion

Science.gov (United States)

Povinelli, L. A.

1979-01-01

Propulsion needs of high performance military aircraft are discussed. Inlet performance, nozzle performance and cooling, and afterburner performance are covered. It is concluded that nonaxisymmetric nozzles provide cleaner external lines and enhanced maneuverability, but the internal flows are more complex. Swirl afterburners show promise for enhanced performance in the high altitude, low Mach number region.

Modeling Complex Workflow in Molecular Diagnostics

Science.gov (United States)

Gomah, Mohamed E.; Turley, James P.; Lu, Huimin; Jones, Dan

2010-01-01

One of the hurdles to achieving personalized medicine has been implementing the laboratory processes for performing and reporting complex molecular tests. The rapidly changing test rosters and complex analysis platforms in molecular diagnostics have meant that many clinical laboratories still use labor-intensive manual processing and testing without the level of automation seen in high-volume chemistry and hematology testing. We provide here a discussion of design requirements and the results of implementation of a suite of lab management tools that incorporate the many elements required for use of molecular diagnostics in personalized medicine, particularly in cancer. These applications provide the functionality required for sample accessioning and tracking, material generation, and testing that are particular to the evolving needs of individualized molecular diagnostics. On implementation, the applications described here resulted in improvements in the turn-around time for reporting of more complex molecular test sets, and significant changes in the workflow. Therefore, careful mapping of workflow can permit design of software applications that simplify even the complex demands of specialized molecular testing. By incorporating design features for order review, software tools can permit a more personalized approach to sample handling and test selection without compromising efficiency. PMID:20007844

HPLC-ESR techniques for detection of complex trapped radicals

International Nuclear Information System (INIS)

Tu Tiecheng; Dong Jirong; Lin Nianyun; Xie Leidong; Liu Rengzhong

1992-01-01

High performance liquid chromatography (HPLC) and ESR combined examination of radical species is an advanced techniques for separation and identification of complex radical species. At SRCL, Waters 990 HPLC has been used to separate the complex trapped radicals and Varian E-112 ESR spectrometer to record the spectra of single trapped radicals after HPLC separation. The advantages of the combined techniques are described as bellow: HPLC is used to separate the long-lived complex trapped radicals derived from reaction of short-lived radicals with spin trap. ESR spectra from single trapped radicals, obtained following HPLC separation of complex trapped radicals, are recorded one by one and well resolved. The structures of short-lived radicals can be inferred from the ESR spectra of the long-lived trapped radicals

Influence of cueing on the preparation and execution of untrained and trained complex motor responses

Directory of Open Access Journals (Sweden)

S.R. Alouche

2012-05-01

Full Text Available This study investigated the influence of cueing on the performance of untrained and trained complex motor responses. Healthy adults responded to a visual target by performing four sequential movements (complex response or a single movement (simple response of their middle finger. A visual cue preceded the target by an interval of 300, 1000, or 2000 ms. In Experiment 1, the complex and simple responses were not previously trained. During the testing session, the complex response pattern varied on a trial-by-trial basis following the indication provided by the visual cue. In Experiment 2, the complex response and the simple response were extensively trained beforehand. During the testing session, the trained complex response pattern was performed in all trials. The latency of the untrained and trained complex responses decreased from the short to the medium and long cue-target intervals. The latency of the complex response was longer than that of the simple response, except in the case of the trained responses and the long cue-target interval. These results suggest that the preparation of untrained complex responses cannot be completed in advance, this being possible, however, for trained complex responses when enough time is available. The duration of the 1st submovement, 1st pause and 2nd submovement of the untrained and the trained complex responses increased from the short to the long cue-target interval, suggesting that there is an increase of online programming of the response possibly related to the degree of certainty about the moment of target appearance.

Integrated pollution control for oil refinery complexes

Energy Technology Data Exchange (ETDEWEB)

Kiperstok, A [Bahia Univ., Salvador, BA (Brazil); Sharratt, P N [Manchester Univ. (United Kingdom). Inst. of Science and Technology

1994-12-31

Improving environmental performance of oil refineries is a complex task. Emission limits, operating constraints, available technologies, operating techniques, and local environment sensitivity must all be considered. This work describes efforts to build an interactive software to deal with this problem. 8 refs., 5 figs.

Integrated pollution control for oil refinery complexes

Energy Technology Data Exchange (ETDEWEB)

Kiperstok, A. [Bahia Univ., Salvador, BA (Brazil); Sharratt, P.N. [Manchester Univ. (United Kingdom). Inst. of Science and Technology

1993-12-31

Improving environmental performance of oil refineries is a complex task. Emission limits, operating constraints, available technologies, operating techniques, and local environment sensitivity must all be considered. This work describes efforts to build an interactive software to deal with this problem. 8 refs., 5 figs.

Westinghouse loading pattern search methodology for complex core designs

International Nuclear Information System (INIS)

Chao, Y.A.; Alsop, B.H.; Johansen, B.J.; Morita, T.

1991-01-01

Pressurized water reactor core designs have become more complex and must meet a plethora of design constraints. Trends have been toward longer cycles with increased discharge burnup, increased burnable absorber (BA) number, mixed BA types, reduced radial leakage, axially blanketed fuel, and multiple-batch feed fuel regions. Obtaining economical reload core loading patterns (LPs) that meet design criteria is a difficult task to do manually. Automated LP search tools are needed. An LP search tool cannot possibly perform an exhaustive search because of the sheer size of the combinatorial problem. On the other hand, evolving complexity of the design features and constraints often invalidates expert rules based on past design experiences. Westinghouse has developed a sophisticated loading pattern search methodology. This methodology is embodied in the LPOP code, which Westinghouse nuclear designers use extensively. The LPOP code generates a variety of LPs meeting design constraints and performs a two-cycle economic evaluation of the generated LPs. The designer selects the most appropriate patterns for fine tuning and evaluation by the design codes. This paper describes the major features of the LPOP methodology that are relevant to fulfilling the aforementioned requirements. Data and examples are also provided to demonstrate the performance of LPOP in meeting the complex design needs

Threatening the Patriarchy: Teaching as Performance

Science.gov (United States)

Falter, Michelle M.

2016-01-01

This article brings into conversation theories of performance and performativity to argue that the analogy of a teacher as a performer is a very complex discourse that both empowers and disempowers women teachers. As the field of teachers is increasingly comprised of women and the education policy and administrative leadership fields is…

The Computational Complexity, Parallel Scalability, and Performance of Atmospheric Data Assimilation Algorithms

Science.gov (United States)

Lyster, Peter M.; Guo, J.; Clune, T.; Larson, J. W.; Atlas, Robert (Technical Monitor)

2001-01-01

The computational complexity of algorithms for Four Dimensional Data Assimilation (4DDA) at NASA's Data Assimilation Office (DAO) is discussed. In 4DDA, observations are assimilated with the output of a dynamical model to generate best-estimates of the states of the system. It is thus a mapping problem, whereby scattered observations are converted into regular accurate maps of wind, temperature, moisture and other variables. The DAO is developing and using 4DDA algorithms that provide these datasets, or analyses, in support of Earth System Science research. Two large-scale algorithms are discussed. The first approach, the Goddard Earth Observing System Data Assimilation System (GEOS DAS), uses an atmospheric general circulation model (GCM) and an observation-space based analysis system, the Physical-space Statistical Analysis System (PSAS). GEOS DAS is very similar to global meteorological weather forecasting data assimilation systems, but is used at NASA for climate research. Systems of this size typically run at between 1 and 20 gigaflop/s. The second approach, the Kalman filter, uses a more consistent algorithm to determine the forecast error covariance matrix than does GEOS DAS. For atmospheric assimilation, the gridded dynamical fields typically have More than 10(exp 6) variables, therefore the full error covariance matrix may be in excess of a teraword. For the Kalman filter this problem can easily scale to petaflop/s proportions. We discuss the computational complexity of GEOS DAS and our implementation of the Kalman filter. We also discuss and quantify some of the technical issues and limitations in developing efficient, in terms of wall clock time, and scalable parallel implementations of the algorithms.

Visual search in ecological and non-ecological displays: evidence for a non-monotonic effect of complexity on performance.

Directory of Open Access Journals (Sweden)

Philippe Chassy

Full Text Available Considerable research has been carried out on visual search, with single or multiple targets. However, most studies have used artificial stimuli with low ecological validity. In addition, little is known about the effects of target complexity and expertise in visual search. Here, we investigate visual search in three conditions of complexity (detecting a king, detecting a check, and detecting a checkmate with chess players of two levels of expertise (novices and club players. Results show that the influence of target complexity depends on level of structure of the visual display. Different functional relationships were found between artificial (random chess positions and ecologically valid (game positions stimuli: With artificial, but not with ecologically valid stimuli, a "pop out" effect was present when a target was visually more complex than distractors but could be captured by a memory chunk. This suggests that caution should be exercised when generalising from experiments using artificial stimuli with low ecological validity to real-life stimuli.

Dynamics of complexation of a charged dendrimer by linear polyelectrolyte: Computer modelling

NARCIS (Netherlands)

Lyulin, S.V.; Darinskii, A.A.; Lyulin, A.V.

2007-01-01

Brownian-dynamics simulations have been performed for complexes formed by a charged dendrimer and a long oppositely charged linear polyelectrolyte when overcharging phenomenon is always observed. After a complex formation the orientational mobility of the individual dendrimer bonds, the fluctuations

Cross-modal links among vision, audition, and touch in complex environments.

Science.gov (United States)

Ferris, Thomas K; Sarter, Nadine B

2008-02-01

This study sought to determine whether performance effects of cross-modal spatial links that were observed in earlier laboratory studies scale to more complex environments and need to be considered in multimodal interface design. It also revisits the unresolved issue of cross-modal cuing asymmetries. Previous laboratory studies employing simple cues, tasks, and/or targets have demonstrated that the efficiency of processing visual, auditory, and tactile stimuli is affected by the modality, lateralization, and timing of surrounding cues. Very few studies have investigated these cross-modal constraints in the context of more complex environments to determine whether they scale and how complexity affects the nature of cross-modal cuing asymmetries. Amicroworld simulation of battlefield operations with a complex task set and meaningful visual, auditory, and tactile stimuli was used to investigate cuing effects for all cross-modal pairings. Significant asymmetric performance effects of cross-modal spatial links were observed. Auditory cues shortened response latencies for collocated visual targets but visual cues did not do the same for collocated auditory targets. Responses to contralateral (rather than ipsilateral) targets were faster for tactually cued auditory targets and each visual-tactile cue-target combination, suggesting an inhibition-of-return effect. The spatial relationships between multimodal cues and targets significantly affect target response times in complex environments. The performance effects of cross-modal links and the observed cross-modal cuing asymmetries need to be examined in more detail and considered in future interface design. The findings from this study have implications for the design of multimodal and adaptive interfaces and for supporting attention management in complex, data-rich domains.

Speeding up the MATLAB complex networks package using graphic processors

International Nuclear Information System (INIS)

Zhang Bai-Da; Wu Jun-Jie; Li Xin; Tang Yu-Hua

2011-01-01

The availability of computers and communication networks allows us to gather and analyse data on a far larger scale than previously. At present, it is believed that statistics is a suitable method to analyse networks with millions, or more, of vertices. The MATLAB language, with its mass of statistical functions, is a good choice to rapidly realize an algorithm prototype of complex networks. The performance of the MATLAB codes can be further improved by using graphic processor units (GPU). This paper presents the strategies and performance of the GPU implementation of a complex networks package, and the Jacket toolbox of MATLAB is used. Compared with some commercially available CPU implementations, GPU can achieve a speedup of, on average, 11.3×. The experimental result proves that the GPU platform combined with the MATLAB language is a good combination for complex network research. (interdisciplinary physics and related areas of science and technology)

Design, Construction and Performance Evaluation of Multiple ...

African Journals Online (AJOL)

The complex casting machine has been designed to perform the following techniques: gravity casting, stir casting, squeeze casting, vacuum casting, compocasting and thixoforming. All these casting techniques have been integrated into this complex casting machine as different units which work with the help of automation.

Authentic Performance of Complex Problem-Solving Tasks with an EPSS.

Science.gov (United States)

Leighton, Chet; McCabe, Cynthia

Just-In-Time Learning (JIT Learning) is a semester-long graduate course that teaches corporate trainers and instructional designers how to design performance improvement interventions. This course is part of a Master's program in Instructional Technology at San Francisco State University. The course has been offered three times and has been…

Safety KPIs - Monitoring of safety performance

Directory of Open Access Journals (Sweden)

Andrej Lališ

2014-09-01

Full Text Available This paper aims to provide brief overview of aviation safety development focusing on modern trends represented by implementation of Safety Key Performance Indicators. Even though aviation is perceived as safe means of transport, it is still struggling with its complexity given by long-term growth and robustness which it has reached today. Thus nowadays safety issues are much more complex and harder to handle than ever before. We are more and more concerned about organizational factors and control mechanisms which have potential to further increase level of aviation safety. Within this paper we will not only introduce the concept of Key Performance Indicators in area of aviation safety as an efficient control mechanism, but also analyse available legislation and documentation. Finally we will propose complex set of indicators which could be applied to Czech Air Navigation Service Provider.

Robots that can adapt like animals.

Science.gov (United States)

Cully, Antoine; Clune, Jeff; Tarapore, Danesh; Mouret, Jean-Baptiste

2015-05-28

Robots have transformed many industries, most notably manufacturing, and have the power to deliver tremendous benefits to society, such as in search and rescue, disaster response, health care and transportation. They are also invaluable tools for scientific exploration in environments inaccessible to humans, from distant planets to deep oceans. A major obstacle to their widespread adoption in more complex environments outside factories is their fragility. Whereas animals can quickly adapt to injuries, current robots cannot 'think outside the box' to find a compensatory behaviour when they are damaged: they are limited to their pre-specified self-sensing abilities, can diagnose only anticipated failure modes, and require a pre-programmed contingency plan for every type of potential damage, an impracticality for complex robots. A promising approach to reducing robot fragility involves having robots learn appropriate behaviours in response to damage, but current techniques are slow even with small, constrained search spaces. Here we introduce an intelligent trial-and-error algorithm that allows robots to adapt to damage in less than two minutes in large search spaces without requiring self-diagnosis or pre-specified contingency plans. Before the robot is deployed, it uses a novel technique to create a detailed map of the space of high-performing behaviours. This map represents the robot's prior knowledge about what behaviours it can perform and their value. When the robot is damaged, it uses this prior knowledge to guide a trial-and-error learning algorithm that conducts intelligent experiments to rapidly discover a behaviour that compensates for the damage. Experiments reveal successful adaptations for a legged robot injured in five different ways, including damaged, broken, and missing legs, and for a robotic arm with joints broken in 14 different ways. This new algorithm will enable more robust, effective, autonomous robots, and may shed light on the principles

Complex chemistry of Np(V) in aqueous solutions

International Nuclear Information System (INIS)

Inoue, Yasushi

1989-01-01

Despite the importance of Np(V) in both the nuclear chemical engineering and the actinoid chemistry, little work has been performed on the complex chemistry of Np(V) in aqueous solutions, since Np(V) reacts less readily with various ligands. The author has directed his effort to understand the chemical behavior of Np(V) in aqueous solutions, especially the determination of the stability constants of Np(V) complexes with various ligands. A part of the results obtained so far is presented in the following order. (1) The synergistic extraction of Np(V) as a method for studying the complex chemistry of Np(V): TTA-MTOA(methyltrioctylammonium chloride), TTA-phen and TTA-TOPO. (2) The determination of the stability constants of Np(V) complexes with 22 organic- and 5 inorganic ligands by means of the solvent extraction. (3) The distribution of the chemical species of Np(V) in solutions under various conditions

Impact of gastrectomy procedural complexity on surgical outcomes and hospital comparisons.

Science.gov (United States)

Mohanty, Sanjay; Paruch, Jennifer; Bilimoria, Karl Y; Cohen, Mark; Strong, Vivian E; Weber, Sharon M

2015-08-01

Most risk adjustment approaches adjust for patient comorbidities and the primary procedure. However, procedures done at the same time as the index case may increase operative risk and merit inclusion in adjustment models for fair hospital comparisons. Our objectives were to evaluate the impact of surgical complexity on postoperative outcomes and hospital comparisons in gastric cancer surgery. Patients who underwent gastric resection for cancer were identified from a large clinical dataset. Procedure complexity was characterized using secondary procedure CPT codes and work relative value units (RVUs). Regression models were developed to evaluate the association between complexity variables and outcomes. The impact of complexity adjustment on model performance and hospital comparisons was examined. Among 3,467 patients who underwent gastrectomy for adenocarcinoma, 2,171 operations were distal and 1,296 total. A secondary procedure was reported for 33% of distal gastrectomies and 59% of total gastrectomies. Six of 10 secondary procedures were associated with adverse outcomes. For example, patients who underwent a synchronous bowel resection had a higher risk of mortality (odds ratio [OR], 2.14; 95% CI, 1.07-4.29) and reoperation (OR, 2.09; 95% CI, 1.26-3.47). Model performance was slightly better for nearly all outcomes with complexity adjustment (mortality c-statistics: standard model, 0.853; secondary procedure model, 0.858; RVU model, 0.855). Hospital ranking did not change substantially after complexity adjustment. Surgical complexity variables are associated with adverse outcomes in gastrectomy, but complexity adjustment does not affect hospital rankings appreciably. Copyright © 2015 Elsevier Inc. All rights reserved.

ComplexViewer: visualization of curated macromolecular complexes.

Science.gov (United States)

Combe, Colin W; Sivade, Marine Dumousseau; Hermjakob, Henning; Heimbach, Joshua; Meldal, Birgit H M; Micklem, Gos; Orchard, Sandra; Rappsilber, Juri

2017-11-15

Proteins frequently function as parts of complexes, assemblages of multiple proteins and other biomolecules, yet network visualizations usually only show proteins as parts of binary interactions. ComplexViewer visualizes interactions with more than two participants and thereby avoids the need to first expand these into multiple binary interactions. Furthermore, if binding regions between molecules are known then these can be displayed in the context of the larger complex. freely available under Apache version 2 license; EMBL-EBI Complex Portal: http://www.ebi.ac.uk/complexportal; Source code: https://github.com/MICommunity/ComplexViewer; Package: https://www.npmjs.com/package/complexviewer; http://biojs.io/d/complexviewer. Language: JavaScript; Web technology: Scalable Vector Graphics; Libraries: D3.js. colin.combe@ed.ac.uk or juri.rappsilber@ed.ac.uk. © The Author 2017. Published by Oxford University Press.

In vitro/in vivo performance of different complexes of itraconazole used in the treatment of vaginal candidiasis

Directory of Open Access Journals (Sweden)

Mohammad Aamir Mirza

2012-12-01

Full Text Available A large majority of new chemical entities and many existing drug molecules exhibit poor aqueous solubility, which may limit their potential use in developing drug formulations, with optimum bioavailability. One of the approaches to improve the solubility of a poorly water soluble drug and eventually its bioavailability is complexation with agents like humic acid (HA, fulvic acid (FA, β-cyclodextrin (β-CD, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD and caffeine (Caff. The current work emphasized at employing these agents to prepare different complexes and their in vitro/in vivo assessment. All the complexes evaluated for their complexation efficiency and authenticated by molecular modeling; conformational analysis, differential scanning calorimetry (DSC, X-ray diffraction (XRD, nuclear magnetic resonance (NMR and mass spectroscopy. Furthermore, the complexes were assessed in an in vivo, rat vaginal model for their efficacy in treatment of vaginal candidiasis. Amongst the five tested complexes, fulvic acid-itraconazole complex yielded better solubility as well as in vivo efficacy and therefore may further be explored for developing a commercial formulation for treating vaginal candidiasis.A maioria das novas entidades químicas e muitas moléculas de fármacos existentes apresenta fraca solubilidade em água, o que pode limitar seu uso potencial no desenvolvimento de formulações com biodisponibilidade ideal. Uma das abordagens para melhorar a solubilidade de um fármaco pouco solúvel em água e, eventualmente, a sua biodisponibilidade é a complexação com agentes como o ácido húmico (HA, ácido fúlvico (FA, β-ciclodextrina (β-CD, 2-hidroxipropil-β-ciclodextrina (HP-β-CD e cafeína (Caff. O presente trabalho baseia-se no uso desses agentes para preparar diferentes complexos e suas avaliações in vitro/in vivo. Todos os complexos foram avaliados quanto à eficiência de complexação por modelação molecular, análise conformacional

Efficient organic light-emitting devices with platinum-complex emissive layer

KAUST Repository

Yang, Xiaohui

2011-01-18

We report efficient organic light-emitting devices having a platinum-complex emissive layer with the peak external quantum efficiency of 17.5% and power efficiency of 45 lm W−1. Variation in the device performance with platinum-complex layer thickness can be attributed to the interplay between carrier recombination and intermolecular interactions in the layer. Efficient white devices using double platinum-complex layers show the external quantum efficiency of 10%, the Commission Internationale d’Énclairage coordinates of (0.42, 0.41), and color rendering index of 84 at 1000 cd m−2.

Efficient organic light-emitting devices with platinum-complex emissive layer

KAUST Repository

Yang, Xiaohui; Wu, Fang-Iy; Haverinen, Hanna; Li, Jian; Cheng, Chien-Hong; Jabbour, Ghassan E.

2011-01-01

We report efficient organic light-emitting devices having a platinum-complex emissive layer with the peak external quantum efficiency of 17.5% and power efficiency of 45 lm W−1. Variation in the device performance with platinum-complex layer thickness can be attributed to the interplay between carrier recombination and intermolecular interactions in the layer. Efficient white devices using double platinum-complex layers show the external quantum efficiency of 10%, the Commission Internationale d’Énclairage coordinates of (0.42, 0.41), and color rendering index of 84 at 1000 cd m−2.

A Novel Modified Algorithm with Reduced Complexity LDPC Code Decoder

Directory of Open Access Journals (Sweden)

Song Yang

2014-10-01

Full Text Available A novel efficient decoding algorithm reduced the sum-product algorithm (SPA Complexity with LPDC code is proposed. Base on the hyperbolic tangent rule, modified the Check node update with two horizontal process, which have similar calculation, Motivated by the finding that sun- min (MS algorithm reduce the complexity reducing the approximation error in the horizontal process, simplify the information weight small part. Compared with the exiting approximations, the proposed method is less computational complexity than SPA algorithm. Simulation results show that the author algorithm can achieve performance very close SPA.

Myocardial ischemia analysis based on electrocardiogram QRS complex

International Nuclear Information System (INIS)

Song, J.; Yan, H.; Xu, Z.; Yu, X.; Zhu, R.

2011-01-01

Full text: Electrocardiogram (ECG) is an economic, convenient, and non-invasive detecting tool in myocardial ischemia (MI), and its clinical appearance is mainly exhibited by the changes in ST-T complex. Recently, QRS complex characters were proposed to analyze MI by more and more researchers. In this paper, various QRS complex characters were extracted in ECG signals, and their relationship was analyzed systematically. As a result, these characters were divided into two groups, and there existed good relationship among them for each group, while the poor relationship between the groups. Then these QRS complex characters were applied for statistical analysis on MI, and five characters had significant differences after ECG recording verification, which were: QRS upward and downward slopes, transient heart rate, angle R and angle Q. On the other hand, these QRS complex characters were analyzed in frequency domain. Experimental results showed that the frequency features of RR interval series (Heart Rate Variability, HRV), and QRS barycenter sequence had signjficant differences between MI states and normal states. Moreover, QRS barycenter sequence performed better. (author)

Design, Manufacturing, and In Vitro Testing of a Patient-Specific Shape-Memory Expander for Nose Reconstruction With Forehead Flap Technique.

Science.gov (United States)

Borghi, Alessandro; Rodgers, Will; Schievano, Silvia; Ponniah, Allan; O'Hara, Justine; Jeelani, Owase; Dunaway, David

2016-01-01

Forehead skin is widely acknowledged as a good donor site for total nasal reconstruction, thanks to its matching color, texture, and abundant vascularity. The forehead flap technique uses an axial pattern flap forehead skin to replace missing nasal tissue. To increase the amount of available tissue and reduce the size of the tissue defect after flap mobilization, tissue expanders may be used. Although this is a relatively established technique, limitations include reduced moldability of the forehead skin (which is thicker than the nasal skin), and the need for multiple sessions of expansion to achieve a sufficient yield to close the forehead.Shape-memory metals, such as nitinol, can be programmed to "remember" complex shapes. In this work, the methodology for producing a prototype of nitinol tissue expander able to mold the skin in a predetermined patient-specific skin shape is described. A realistic nose mold was manufactured using metal rapid prototyping; nitinol sheet and mesh were molded into nose-shape constructs, having hyperelastic as well as shape-memory capability. Computed tomography scanning was performed to assess the ability of the structure to regain its shape after phase transformation upon cooling within 2% of initial dimensions. The prototypes were implanted in a pig forehead to test its ability to impose a nose shape to the forehead skin.The shape-memory properties of nitinol offer the possibility of producing bespoke tissue expanders able to deliver complex, precisely designed skin envelopes. The hyperelastic properties of nitinol allow constant preprogrammed expansion forces to be generated throughout the expansion process.

Organization Features and School Performance