Developing countries SMEs innovation characteristics and performance

DEFF Research Database (Denmark)

Vang, Jan; Rezaei, Shahamak; Baklanov, Nikita

An econometric study analysing developing countries’ SMEs innovation characteristics and their correlation with performance.......An econometric study analysing developing countries’ SMEs innovation characteristics and their correlation with performance....

Solving the multigroup adjoint transport equations using the method of cyclic characteristics

Energy Technology Data Exchange (ETDEWEB)

Assawaroongruengchot, M.; Marleau, G. [Ecole Polytechnique de Montreal, Inst. de genie nucleaire, Montreal, Quebec (Canada)]. E-mail: monchai.assawar@polymtl.ca

2005-07-01

The adjoint transport solution algorithm based on the method of cyclic characteristics (MOCC) is developed for the heterogeneous 2D geometries. The adjoint characteristics equation associated with a cyclic tracking line is formulated, then a closed form for adjoint angular flux can be determined. The acceleration techniques are implemented using the group-reduction and group-splitting techniques. To demonstrate the efficacy of the algorithm, the calculations are performed on the 37 pin CANDU cell and on the Watanabe-Maynard benchmark problem. Comparisons of adjoint flux and k{sub eff} results obtained by MOCC and collision probability (CP) methods are performed. The mathematical relationship between pseudo-adjoint flux obtained by CP method and adjoint flux by MOCC method is presented. (author)

Board characteristics, governance objectives, and hospital performance

DEFF Research Database (Denmark)

Thiel, Andrea; Winter, Vera; Büchner, Vera Antonia

2018-01-01

membership relates to board characteristics and financial performance. METHODOLOGY: Using factor analysis, we identify latent classes of governance objectives and use hierarchical cluster analysis to detect distinct clusters with varying emphasis on the classes. We then use multinomial regression to explore...... the associations between cluster membership and board characteristics (size, gender diversity, and occupational diversity) and examine the associations between clusters and financial performance using OLS regression. RESULTS: Classes of objectives reflecting three governance theories-agency theory, stewardship...... and hospital financial performance, with two of three groups performing significantly better than the reference group. CONCLUSION: High performance in hospitals can be the result of governance logics, which, compared to simple board characteristics, are associated with better financial outcomes. PRACTICE...

An efficient preconditioning technique using Krylov subspace methods for 3D characteristics solvers

International Nuclear Information System (INIS)

Dahmani, M.; Le Tellier, R.; Roy, R.; Hebert, A.

2005-01-01

The Generalized Minimal RESidual (GMRES) method, using a Krylov subspace projection, is adapted and implemented to accelerate a 3D iterative transport solver based on the characteristics method. Another acceleration technique called the self-collision rebalancing technique (SCR) can also be used to accelerate the solution or as a left preconditioner for GMRES. The GMRES method is usually used to solve a linear algebraic system (Ax=b). It uses K(r (o) ,A) as projection subspace and AK(r (o) ,A) for the orthogonalization of the residual. This paper compares the performance of these two combined methods on various problems. To implement the GMRES iterative method, the characteristics equations are derived in linear algebra formalism by using the equivalence between the method of characteristics and the method of collision probability to end up with a linear algebraic system involving fluxes and currents. Numerical results show good performance of the GMRES technique especially for the cases presenting large material heterogeneity with a scattering ratio close to 1. Similarly, the SCR preconditioning slightly increases the GMRES efficiency

Spectral analysis of an algebraic collapsing acceleration for the characteristics method

International Nuclear Information System (INIS)

Le Tellier, R.; Hebert, A.

2005-01-01

A spectral analysis of a diffusion synthetic acceleration called Algebraic Collapsing Acceleration (ACA) was carried out in the context of the characteristics method to solve the neutron transport equation. Two analysis were performed in order to assess the ACA performances. Both a standard Fourier analysis in a periodic and infinite slab-geometry and a direct spectral analysis for a finite slab-geometry were investigated. In order to evaluate its performance, ACA was compared with two competing techniques used to accelerate the convergence of the characteristics method, the Self-Collision Re-balancing technique and the Asymptotic Synthetic Acceleration. In the restricted framework of 1-dimensional slab-geometries, we conclude that ACA offers a good compromise between the reduction of the spectral radius of the iterative matrix and the resources to construct, store and solve the corrective system. A comparison on a monoenergetic 2-dimensional benchmark was performed and tends to confirm these conclusions. (authors)

COMPETENCY, ENTREPRENEUR CHARACTERISTIC AND BUSINESS PERFORMANCE: STUDY OF THE PEMPEK BUSINESS IN PALEMBANG

Directory of Open Access Journals (Sweden)

Fransiska Soejono

2015-01-01

Full Text Available The purpose of this study was to examine empirically the effects of entrepreneurial compe-tencies and characteristics on business performance. Previous studies found that competencies and entrepreneurial characteristics significantly influenced business performance. A quantita-tive method was used and 122 respondents were involved as the sample in this study, who were pempek business owners in Palembang, South Sumatra. The results indicated an effect from entrepreneurial competencies on business performance. It was also found that the entrepre-neurs’ characteristics (owners’ ages significantly affected the businesses’ performance. This implication requires some sort of course or program for the entrepreneurs to improve their competence to direct the owners to gain better business performance. The growing age of the business owners requires equal insights to ensure age does not stop the owners from improving their business’ performance.

Model Of Emergency Department Nurse Performance Improvement Based on Association of Individual Characteristic, Organization Characteristic and Job Characteristic

OpenAIRE

Bogar, Maria Margaretha; Nursalam, Nursalam; Dewi, Yulis Setiya

2017-01-01

Introduction: Nursing care is integral part of health care and having important role in management of patient with emergency condition. The purpose of this research was to develop nurse performance improvement model based on individual, organization and job characteristics association in Emergency Department of RSUD dr TC Hillers Maumere. Method: This was an explanative survey by cross sectional approach held on July -August 2012. Respondents in this study were 22 nurses and 44 patients were ...

Optimization of performance and emission characteristics of PPCCI engine fuelled with ethanol and diesel blends using grey-Taguchi method

Science.gov (United States)

Natarajan, S.; Pitchandi, K.; Mahalakshmi, N. V.

2018-02-01

The performance and emission characteristics of a PPCCI engine fuelled with ethanol and diesel blends were carried out on a single cylinder air cooled CI engine. In order to achieve the optimal process response with a limited number of experimental cycles, multi objective grey relational analysis had been applied for solving a multiple response optimization problem. Using grey relational grade and signal-to-noise ratio as a performance index, a combination of input parameters was prefigured so as to achieve optimum response characteristics. It was observed that 20% premixed ratio of blend was most suitable for use in a PPCCI engine without significantly affecting the engine performance and emissions characteristics.

Investigating the effect of K-characteristic radiation on the performance of nuclear medicine scintillators by Monte Carlo methods

International Nuclear Information System (INIS)

Liaparinos, Panagiotis; Kandarakis, Ioannis; Cavouras, Dionisis; Delis, Harry; Panayiotakis, George

2006-01-01

The aim of this study was to evaluate the effect of K-characteristic radiation on the performance of scintillator crystals incorporated in nuclear medicine detectors (LSO, BGO, GSO). K-characteristic radiation is produced within materials of at least one high atomic number element (e.g. Lu, Gd, Bi). This radiation may either be reabsorbed or it may escape the scintillator. In both cases the light emission efficiency of the scintillator may be affected resulting in either spatial or energy resolution degradation. A computational program, based on Monte Carlo methods, was developed in order to simulate the transport of K-characteristic radiation within the most commonly used scintillator materials. Crystal thickness was allowed to vary from 0.5 up to 15 mm. A monoenergetic pencil beam, with energy varying from 0.60 to 0.511 MeV was considered to fall on the center of the crystal surface. The dominant γ-ray interactions (elastic and inelastic scattering and photoelectric absorption) were taken into account in the simulation. Results showed that, depending on crystal thickness, incident photon energy and scintillator's intrinsic properties (L or K-fluorescence yield, effective atomic number and density), the scintillator's emission efficiency may be significantly reduced and affect spatial or energy resolution

The method of modular characteristic direction probabilities in MPACT

Energy Technology Data Exchange (ETDEWEB)

Liu, Z. [School of Nuclear Science and Technology, Xi' an Jiaotong University, No. 28 Xianning west road, Xi' an, Shaanxi 710049 (China); Kochunas, B.; Collins, B.; Downar, T. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2200 Bonisteel, Ann Arbor, MI 48109 (United States); Wu, H. [School of Nuclear Science and Technology, Xi' an Jiaotong University, No. 28 Xianning west road, Xi' an, Shaanxi 710049 (China)

2013-07-01

The method of characteristic direction probabilities (CDP) is based on a modular ray tracing technique which combines the benefits of the collision probability method (CPM) and the method of characteristics (MOC). This past year CDP was implemented in the transport code MPACT for 2-D and 3-D transport calculations. By only coupling the fine mesh regions passed by the characteristic rays in the particular direction, the scale of the probabilities matrix is much smaller compared to the CPM. At the same time, the CDP has the same capacity of dealing with the complicated geometries with the MOC, because the same modular ray tracing techniques are used. Results from the C5G7 benchmark problems are given for different cases to show the accuracy and efficiency of the CDP compared to MOC. For the cases examined, the CDP and MOC methods were seen to differ in k{sub eff} by about 1-20 pcm, and the computational efficiency of the CDP appears to be better than the MOC for some problems. However, in other problems, particularly when the CDP matrices have to be recomputed from changing cross sections, the CDP does not perform as well. This indicates an area of future work. (authors)

Investigation on multi-objective performance optimization algorithm application of fan based on response surface method and entropy method

Science.gov (United States)

Zhang, Li; Wu, Kexin; Liu, Yang

2017-12-01

A multi-objective performance optimization method is proposed, and the problem that single structural parameters of small fan balance the optimization between the static characteristics and the aerodynamic noise is solved. In this method, three structural parameters are selected as the optimization variables. Besides, the static pressure efficiency and the aerodynamic noise of the fan are regarded as the multi-objective performance. Furthermore, the response surface method and the entropy method are used to establish the optimization function between the optimization variables and the multi-objective performances. Finally, the optimized model is found when the optimization function reaches its maximum value. Experimental data shows that the optimized model not only enhances the static characteristics of the fan but also obviously reduces the noise. The results of the study will provide some reference for the optimization of multi-objective performance of other types of rotating machinery.

Modeling Nanoscale FinFET Performance by a Neural Network Method

Directory of Open Access Journals (Sweden)

Jin He

2017-07-01

Full Text Available This paper presents a neural network method to model nanometer FinFET performance. The principle of this method is firstly introduced and its application in modeling DC and conductance characteristics of nanoscale FinFET transistor is demonstrated in detail. It is shown that this method does not need parameter extraction routine while its prediction of the transistor performance has a small relative error within 1 % compared with measured data, thus this new method is as accurate as the physics based surface potential model.

Performance and combustion characteristics of direct-injection stratified-charge rotary engines

Science.gov (United States)

Nguyen, Hung Lee

1987-01-01

Computer simulations of the direct-injection stratified-charge (DISC) Wankel engine have been used to calculate heat release rates and performance and efficiency characteristics of the 1007R engine. Engine pressure data have been used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine performance data are compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the Wankel engine with faster combustion, reduced leakage, higher compression ratio, and turbocharging is presented.

Control characteristics and heating performance analysis of automatic thermostatic valves for radiant slab heating system in residential apartments

Energy Technology Data Exchange (ETDEWEB)

Ahn, Byung-Cheon [Department of Building Equipment System Engineering, Kyungwon University, Seongnam City (Korea); Song, Jae-Yeob [Graduate School, Building Equipment System Engineering, Kyungwon University, Seongnam City (Korea)

2010-04-15

Computer simulations and experiments are carried out to research the control characteristics and heating performances for a radiant slab heating system with automatic thermostatic valves in residential apartments. An electrical equivalent R-C circuit is applied to analyze the unsteady heat transfer in the house. In addition, the radiant heat transfer between slabs, ceilings and walls in the room is evaluated by enclosure analysis method. Results of heating performance and control characteristics were determined from control methods such as automatic thermostatic valves, room air temperature-sensing method, water-temperature-sensing method, proportional control method, and On-Off control method. (author)

Research about reactor operator's personality characteristics and performance

International Nuclear Information System (INIS)

Wei Li; He Xuhong; Zhao Bingquan

2003-01-01

To predict and evaluate the reactor operator's performance by personality characteristics is an important part of reactor operator safety assessment. Using related psychological theory combined with the Chinese operator's fact and considering the effect of environmental factors to personality analysis, paper does the research about the about the relationships between reactor operator's performance and personality characteristics, and offers the reference for operator's selection, using and performance in the future. (author)

Parametric study of geohydrologic performance characteristics for geologic waste repositories

International Nuclear Information System (INIS)

Bailey, C.E.; Marine, I.W.

1980-11-01

One of the major objectives of the National Waste Terminal Storage Program is to identify potential geologic sites for storage and isolation of radioactive waste (and possibly irradiated fuel). Potential sites for the storage and isolation of radioactive waste or spent fuel in a geologic rock unit are being carefully evaluated to ensure that radionuclides from the stored waste or fuel will never appear in the biosphere in amounts that would constitute a hazard to the health and safety of the public. The objective of this report is to quantify and present in graphical form the effects of significant geohydrologic and other performance characteristics that would influence the movement of radionuclides from a storage site in a rock unit to the biosphere. The effort in this study was focused on transport by groundwater because that is the most likely method of radionuclide escape. Graphs of the major performance characteristics that influence the transport of radionuclides from a repository to the biosphere by groundwater are presented. The major characteristics addressed are radioactive decay, leach rate, hydraulic conductivity, porosity, groundwater gradient, hydrodynamic dispersion, ion exchange, and distance to the biosphere. These major performance characteristics are combind with each other and with the results of certain other combinations and presented in graphical form to provide the interrelationships of values measured during field studies. The graphical form of presentation should be useful in the screening process of site selection. An appendix illustrates the use of these graphs to assess the suitability of a site

Theory and analysis of accuracy for the method of characteristics direction probabilities with boundary averaging

International Nuclear Information System (INIS)

Liu, Zhouyu; Collins, Benjamin; Kochunas, Brendan; Downar, Thomas; Xu, Yunlin; Wu, Hongchun

2015-01-01

Highlights: • The CDP combines the benefits of the CPM’s efficiency and the MOC’s flexibility. • Boundary averaging reduces the computation effort with losing minor accuracy. • An analysis model is used to justify the choice of optimize averaging strategy. • Numerical results show the performance and accuracy. - Abstract: The method of characteristic direction probabilities (CDP) combines the benefits of the collision probability method (CPM) and the method of characteristics (MOC) for the solution of the integral form of the Botlzmann Transport Equation. By coupling only the fine regions traversed by the characteristic rays in a particular direction, the computational effort required to calculate the probability matrices and to solve the matrix system is considerably reduced compared to the CPM. Furthermore, boundary averaging is performed to reduce the storage and computation but the capability of dealing with complicated geometries is preserved since the same ray tracing information is used as in MOC. An analysis model for the outgoing angular flux is used to analyze a variety of outgoing angular flux averaging methods for the boundary and to justify the choice of optimize averaging strategy. The boundary average CDP method was then implemented in the Michigan PArallel Characteristic based Transport (MPACT) code to perform 2-D and 3-D transport calculations. The numerical results are given for different cases to show the effect of averaging on the outgoing angular flux, region scalar flux and the eigenvalue. Comparison of the results with the case with no averaging demonstrates that an angular dependent averaging strategy is possible for the CDP to improve its computational performance without compromising the achievable accuracy

Study of the method to estimate the hydraulic characteristics in rock masses by using elastic wave

International Nuclear Information System (INIS)

Katsu, Kenta; Ohnishi, Yuzo; Nishiyama, Satoshi; Yano, Takao; Ando, Kenichi; Yoshimura, Kimitaka

2008-01-01

In the area of radioactive waste repository, estimating radionuclide migration through the rock mass is an important factor for assessment of the repository. The purpose of this study is to develop a method to estimate hydraulic characteristics of rock masses by using elastic wave velocity dispersion. This method is based on dynamics poroelastic relations such as Biot and BISQ theories. These theories indicate relations between velocity dispersion and hydraulic characteristics. In order to verify the validity of these theories in crystalline rocks, we performed laboratory experiments. The results of experiments show the dependency of elastic wave velocity on its frequency. To test the applicability of this method to real rock masses, we performed in-situ experiment for tuff rock masses. The results of in-situ experiment show the possibility as a practical method to estimate the hydraulic characteristics by using elastic wave velocity dispersion. (author)

Nonlinear Performance Characteristics of Flux-Switching PM Motors

Directory of Open Access Journals (Sweden)

E. Ilhan

2013-01-01

Full Text Available Nonlinear performance characteristics of 3-phase flux-switching permanent magnet motors (FSPM are overviewed. These machines show advantages of a robust rotor structure and a high energy density. Research on the FSPM is predominated by topics such as modeling and machine comparison, with little emphasis given on its performance and limits. Performance characteristics include phase flux linkage, phase torque, and phase inductance. In the paper, this analysis is done by a cross-correlation of rotor position and armature current. Due to the high amount of processed data, which cannot be handled analytically within an acceptable time period, a multistatic 2D finite element model (FEM is used. For generalization, the most commonly discussed FSPM topology, 12/10 FSPM, is chosen. Limitations on the motor performance due to the saturation are discussed on each characteristic. Additionally, a focused overview is given on energy conversion loops and dq-axes identification for the FSPM.

Numerical investigation and performance characteristic mapping of an Archimedean screw hydroturbine

Science.gov (United States)

Schleicher, W. Chris

Computational Fluid Dynamics (CFD) is a crucial tool in the design and analysis of hydraulic machinery, especially in the design of a micro hydro turbine. The micro hydro turbine in question is for a low head (less than 60 meters), low volumetric flow rate (0.005 m3/s to 0.5 m 3/s) application with rotation rates varying from 200 RPM to 1500 RPM. The design of the runner geometry is discussed, specifically a non-uniform Archimedean Spiral with an outer diameter of 6 inches and length of 19.5 inches. The transient simulation method, making use of a frame of reference change and a rotating mesh between time-steps, is explained as well as the corresponding boundary conditions. Both simulation methods are compared and are determined to produce similar results. The rotating frame of reference method was determined to be the most suitable method for the mapping of performance characteristic such as required head, torque, power, and efficiency. Results of simulations for a non-uniform Archimedean Spiral are then presented. First, a spectral and temporal convergence study is conducted to make sure that the results are independent of time-step and mesh selection. Performance characteristics of a non-uniform pitched blade turbine are determined for a wide range of volumetric flow rates and rotation rates. The maximum efficiency of the turbine is calculated around 72% for the design of the turbine blade considered in the present study.

Split-Cell Exponential Characteristic Transport Method for Unstructured Tetrahedral Meshes

International Nuclear Information System (INIS)

Brennan, Charles R.; Miller, Rodney L.; Mathews, Kirk A.

2001-01-01

The nonlinear, exponential characteristic (EC) method is extended to unstructured meshes of tetrahedral cells in three-dimensional Cartesian coordinates. The split-cell approach developed for the linear characteristic (LC) method on such meshes is used. Exponential distributions of the source within a cell and of the inflow flux on upstream faces of the cell are assumed. The coefficients of these distributions are determined by nonlinear root solving so as to match the zeroth and first moments of the source or entering flux. Good conditioning is achieved by casting the formulas for the moments of the source, inflow flux, and solution flux as sums of positive functions and by using accurate and robust algorithms for evaluation of those functions. Various test problems are used to compare the performance of the EC and LC methods. The EC method is somewhat less accurate than the LC method in regions of net out leakage but is strictly positive and retains good accuracy with optically thick cells, as in shielding problems, unlike the LC method. The computational cost per cell is greater for the EC method, but the use of substantially coarser meshes can make the EC method less expensive in total cost. The EC method, unlike the LC method, may fail if negative cross sections or angular quadrature weights are used. It is concluded that the EC and LC methods should be practical, reliable, and complimentary schemes for these meshes

Growth performance, carcass and hematological characteristics of ...

African Journals Online (AJOL)

Growth performance, carcass and hematological characteristics of rabbits fed graded levels of tiger nuts ( Cyperus esculentus ) ... (p>0.05) difference between treatments. Results demonstrated that (Cyperus esculentus) could be used up to 5% in rabbit's diets without adverse effect on the animals' performance and health.

CFD method research on characteristics cells in rod bundle fuel assembly

International Nuclear Information System (INIS)

Chen Jie; Chen Bingyan; Zhang Hong

2011-01-01

Two characteristic cells are in AFA-3G fuel assembly, that is typical cell and control rod guide cell. And there are some rules on the arrangement of mixing vanes. For the two characteristic cells, mixing capability is evaluated axially from the point of the first and second kind of sub-channel with CFD method. Mass mixing and heat mixing are interaction but different with each other. Although the mass mixing in the first kind of sub-channel is stronger, the thermal capability of the two is to some tune from the point of heat transfer. In the experiment research on thermal-hydraulic performance of AFA-3G fuel assembly, the arrangements of mixing vanes should refer to the two spacer grids of characteristic cells. (authors)

Performance characteristics of the Mayo/IBM PACS

Science.gov (United States)

Persons, Kenneth R.; Gehring, Dale G.; Pavicic, Mark J.; Ding, Yingjai

1991-07-01

The Mayo Clinic and IBM (at Rochester, Minnesota) have jointly developed a picture archiving system for use with Mayo's MRI and Neuro CT imaging modalities. The communications backbone of the PACS is a portion of the Mayo institutional network: a series of 4-Mbps token rings interconnected by bridges and fiber optic extensions. The performance characteristics of this system are important to understand because they affect the response time a PACS user can expect, and the response time for non-PACS users competing for resources on the institutional network. The performance characteristics of each component and the average load levels of the network were measured for various load distributions. These data were used to quantify the response characteristics of the existing system and to tune a model developed by North Dakota State University Department of Computer Science for predicting response times of more complex topologies.

Performative Schizoid Method

DEFF Research Database (Denmark)

Svabo, Connie

2016-01-01

is presented and an example is provided of a first exploratory engagement with it. The method is used in a specific project Becoming Iris, making inquiry into arts-based knowledge creation during a three month visiting scholarship at a small, independent visual art academy. Using the performative schizoid......A performative schizoid method is developed as a method contribution to performance as research. The method is inspired by contemporary research in the human and social sciences urging experimentation and researcher engagement with creative and artistic practice. In the article, the method...... method in Becoming Iris results in four audio-visual and performance-based productions, centered on an emergent theme of the scholartist as a bird in borrowed feathers. Interestingly, the moral lesson of the fable about the vain jackdaw, who dresses in borrowed peacock feathers and becomes a castout...

Development of methods for measuring materials nuclear characteristics, Phases, I, II, II and IV

International Nuclear Information System (INIS)

Maglic, R.

1963-04-01

This report contains the following phases of the project 'measurement of nuclear characteristics of reactor materials': nuclear performances of the neutron chopper; method for measuring total effective cross sections by transmission method on the chopper; review of methods for measuring activation cross sections; measurement of neutron spectra of the RA reactor and measurement of total effective cross section of gold by using the chopper

Operator performance evaluation using multi criteria decision making methods

Science.gov (United States)

Rani, Ruzanita Mat; Ismail, Wan Rosmanira; Razali, Siti Fatihah

2014-06-01

Operator performance evaluation is a very important operation in labor-intensive manufacturing industry because the company's productivity depends on the performance of its operators. The aims of operator performance evaluation are to give feedback to operators on their performance, to increase company's productivity and to identify strengths and weaknesses of each operator. In this paper, six multi criteria decision making methods; Analytical Hierarchy Process (AHP), fuzzy AHP (FAHP), ELECTRE, PROMETHEE II, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) and VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) are used to evaluate the operators' performance and to rank the operators. The performance evaluation is based on six main criteria; competency, experience and skill, teamwork and time punctuality, personal characteristics, capability and outcome. The study was conducted at one of the SME food manufacturing companies in Selangor. From the study, it is found that AHP and FAHP yielded the "outcome" criteria as the most important criteria. The results of operator performance evaluation showed that the same operator is ranked the first using all six methods.

Covariance of engineering management characteristics with engineering employee performance

Science.gov (United States)

Hesketh, Andrew Arthur

1998-12-01

As business in the 1990's grapples with the impact of continuous improvement and quality to meet market demands, there is an increased need to improve the leadership capabilities of our managers. Engineers have indicated desire for certain managerial characteristics in their leadership but there have been no studies completed that approached the problem of determining what managerial characteristics were best at improving employee performance. This study addressed the idea of identifying certain managerial characteristics that enhance employee performance. In the early 1990's, McDonnell Douglas Aerospace in St. Louis used a forced distribution system and allocated 35% of its employees into a "exceeds expectations" category and 60% into a "meets expectations" category. A twenty-question 5 point Likert scale survey on managerial capabilities was administered to a sample engineering population that also obtained their "expectations" category. A single factor ANOVA on the survey results determined a statistical difference between the "exceeds" and "meets" employees with four of the managerial capability questions. The "exceeds expectations" employee indicated that supervision did a better job of supporting subordinate development, clearly communicating performance expectations, and providing timely performance feedback when compared to the "meets expectations" employee. The "meets expectations" employee felt that their opinions, when different from their supervisor's, were more often ignored when compared to the "exceeds expectations" employee. These four questions relate to two specific managerial characteristics, "gaining (informal) authority and support" or "control" characteristic and "providing assistance and guidance" or "command" characteristic, that can be emphasized in managerial training programs.

A review of hospital characteristics associated with improved performance.

Science.gov (United States)

Brand, Caroline A; Barker, Anna L; Morello, Renata T; Vitale, Michael R; Evans, Sue M; Scott, Ian A; Stoelwinder, Johannes U; Cameron, Peter A

2012-10-01

The objective of this review was to critically appraise the literature relating to associations between high-level structural and operational hospital characteristics and improved performance. The Cochrane Library, MEDLINE (Ovid), CINAHL, proQuest and PsychINFO were searched for articles published between January 1996 and May 2010. Reference lists of included articles were reviewed and key journals were hand searched for relevant articles. and data extraction Studies were included if they were systematic reviews or meta-analyses, randomized controlled trials, controlled before and after studies or observational studies (cohort and cross-sectional) that were multicentre, comparative performance studies. Two reviewers independently extracted data, assigned grades of evidence according to the Australian National Health and Medical Research Council guidelines and critically appraised the included articles. Data synthesis Fifty-seven studies were reported within 12 systematic reviews and 47 observational articles. There was heterogeneity in use and definition of performance outcomes. Hospital characteristics investigated were environment (incentives, market characteristics), structure (network membership, ownership, teaching status, geographical setting, service size) and operational design (innovativeness, leadership, organizational culture, public reporting and patient safety practices, information technology systems and decision support, service activity and planning, workforce design, staff training and education). The strongest evidence for an association with overall performance was identified for computerized physician order entry systems. Some evidence supported the associations with workforce design, use of financial incentives, nursing leadership and hospital volume. There is limited, mainly low-quality evidence, supporting the associations between hospital characteristics and healthcare performance. Further characteristic-specific systematic reviews are

Nanotechnological inventions considerably improve performance characteristics

Directory of Open Access Journals (Sweden)

VLASOV Vladimir Alexeevich

2014-06-01

Full Text Available The invention «The method of production of carbon nanomaterial (RU 2509053» can be used as an additive for concretes and polymers which significantly improves their performance characteristics. The method of production of carbon nanomaterial consists of the following stages: preliminary preparation of sphagnous moss when it is refined from foreign admixtures, dried up to 10% humidity and ground, then ground material is exposed to pyrolysis under the temperature 850–950оC for 1–2 hours and cooled up to the environment temperature. After that amorphous carbon obtained in pyrolysis is treated with mechanical activation in the variable planetary mill for 7–10 hours. The invention makes it possible to provide increased outcome of nanotubes with high cleanliness. The invention «The method of production of nanodispersed metal powders and alloys of them (RU 2509626» relates to the powder metallurgy. Powder metal chloride or powder mixture at least of two metal chlorides is treated in the environment of the water steam which is supplied in reaction space at the rate of 50–100 ml/min at the temperature 400–800оC at the presence of absorbent carbon or introducing carbon oxide (II obtained during dissolution of formic acid HCOOH. The invention provides reliable production of nanodispersed metal powders and alloys of them from 3-d metal range: Ni, Co, Cu, Fe, Zn which can be used in powder metallurgy to improve baking process, in chemical industry as the fillers of polymers and reaction catalysts; as additives to anticorrosive covers, etc.

Influence of course characteristics, student characteristics, and behavior in learning management systems on student performance

OpenAIRE

Conijn, Rianne; Kleingeld, Ad; Matzat, Uwe; Snijders, Chris; van Zaanen, Menno

2016-01-01

The use of learning management systems (LMS) in education make it possible to track students’ online behavior. This data can be used for educational data mining and learning analytics, for example, by predicting student performance. Although LMS data might contain useful predictors, course characteristics and student characteristics have shown to influence student performance as well. However, these different sets of features are rarely combined or compared. Therefore, in the current study we...

Proteus-MOC: A 3D deterministic solver incorporating 2D method of characteristics

International Nuclear Information System (INIS)

Marin-Lafleche, A.; Smith, M. A.; Lee, C.

2013-01-01

A new transport solution methodology was developed by combining the two-dimensional method of characteristics with the discontinuous Galerkin method for the treatment of the axial variable. The method, which can be applied to arbitrary extruded geometries, was implemented in PROTEUS-MOC and includes parallelization in group, angle, plane, and space using a top level GMRES linear algebra solver. Verification tests were performed to show accuracy and stability of the method with the increased number of angular directions and mesh elements. Good scalability with parallelism in angle and axial planes is displayed. (authors)

Proteus-MOC: A 3D deterministic solver incorporating 2D method of characteristics

Energy Technology Data Exchange (ETDEWEB)

Marin-Lafleche, A.; Smith, M. A.; Lee, C. [Argonne National Laboratory, 9700 S. Cass Avenue, Lemont, IL 60439 (United States)

2013-07-01

A new transport solution methodology was developed by combining the two-dimensional method of characteristics with the discontinuous Galerkin method for the treatment of the axial variable. The method, which can be applied to arbitrary extruded geometries, was implemented in PROTEUS-MOC and includes parallelization in group, angle, plane, and space using a top level GMRES linear algebra solver. Verification tests were performed to show accuracy and stability of the method with the increased number of angular directions and mesh elements. Good scalability with parallelism in angle and axial planes is displayed. (authors)

Hydrodynamic characteristics of high speed settling clarifiers by radiotracer method

International Nuclear Information System (INIS)

Griffith Martinez, Jose; Damera Martinez, A.; Ramos Espinosa, K.

2003-01-01

Results achieved in the evaluation of two high-speed settling cane juice Clarifiers, one denominated ICINAZ The Express and the other one a modified SRI, both located at the sugar factory Orlando Gonzalez employing the well established radiotracer method (Tc-99m) are presented Several trials performed simultaneously at the two Clarifiers demonstrated that the modified SRI was capable to assimilate the whole flow capacity of the factory with adequate characteristic of the pattern flux and residence time in the environment of 1 hour. In the other side, ICINAZ The Express Clarifier could only work at relative low flow capacity of the factory with residence time closely to the two hours and achieving occasionally a pattern flux seriously affected by fluctuations in the milling process. The non-availability of a flow meter did not allow to extract more information related to some pattern flux anomalies, nevertheless, the radiotracer method was able to detect certain differences between the two clear juice outlet of the modified SRI Clarifier, probably due some problems in the construction of this equipment. This fact so as other goals achieved in this work, show once more the potentiality of the radiotracer method for this type of study related to the hydrodynamic characteristics of industrial facilities. (Author)

The Influence of Top Management Team Characteristics on BPD Performance

Directory of Open Access Journals (Sweden)

Joy Elly Tulung

2015-12-01

Full Text Available Based on ”upper echelons theory”, this paper investigates the relation between top management team composition and BPD performance. For top management team characteristics, we employ age, level of education, background of education, gender, and functional background, while for measured the BPD performance we employ return on asset (ROA, return on equity (ROE, capital adequacy ratio (CAR, net interest margin (NIM, loan to deposit ratio (LDR, non-performing loan (NPL and operation expenses to operation income (BOPO. The results show that all characteristics have positive significant influences on BPD performance.

Research about reactor operator's personability characteristics and performance

Energy Technology Data Exchange (ETDEWEB)

Wei Li; He Xuhong; Zhao Bingquan [Tsinghua Univ., Institute of Nuclear Energy Technology, Beijing (China)

2003-03-01

To predict and evaluate the reactor operator's performance by personality characteristics is an important part of reactor operator safety assessment. Using related psychological theory combined with the Chinese operator's fact and considering the effect of environmental factors to personality analysis, paper does the research about the about the relationships between reactor operator's performance and personality characteristics, and offers the reference for operator's selection, using and performance in the future. (author)

Relationship Between Job Characteristics And Job Performance Of ...

African Journals Online (AJOL)

The agricultural extension agent is a key stakeholder in extension systems. The nature of their work is so important that it has overriding effect on their job performance. This study investigates the relationship between job characteristics and job performance of agricultural extension agents in Imo and Rivers States, Nigeria.

Impacts of teachers’ competency on job performance in research universities with industry characteristics: Taking academic atmosphere as moderator

Directory of Open Access Journals (Sweden)

Anguo Xu

2014-10-01

Full Text Available Purpose: Research universities with industry characteristics play an irreplaceable role in national economic development and social development. With the rapid development of research universities with industry characteristics in China, these universities face new challenges in managing teachers and promoting their quality. This paper aims to examine the impact of teachers’ competency on job performance in research university with industry characteristics Design/methodology/approach: Based on the behavioral event interview and questionnaire methods, a four-dimension (i.e. basic quality, teaching ability, industry awareness and research capacity competency model was proposed, the influence mechanism of competency on job performance was examined using empirical research. Findings: We found that there is a significant positive correlation between the teachers’ competency level, four dimensions and job performance in research universities with industry characteristics, especially between research capacity, teaching ability, industry awareness and job performance. And academic atmosphere plays a regulatory role in the interaction between the competency and job performance. Practical implications: Our findings can help to improve the management level of teachers in research universities with industry characteristics.Originality/value: The paper introduces the competency theory to the teacher management in research universities with industry characteristics, and gives some interesting findings.

Relationships between Isometric Force-Time Characteristics and Dynamic Performance

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Thomas Dos’Santos

2017-09-01

Full Text Available The purpose of this study was to explore the relationships between isometric mid-thigh pull (IMTP force-time characteristics (peak force and time-specific force vales (100–250 ms and dynamic performance and compare dynamic performance between stronger and weaker athletes. Forty-three athletes from different sports (rowing, soccer, bicycle motocross, and hockey performed three trials of the squat jump (SJ, countermovement jump (CMJ, and IMTP, and performed a one repetition maximum power clean (PC. Reactive strength index modified (RSImod was also calculated from the CMJ. Statistically significant large correlations between IMTP force-time characteristics and PC (ρ = 0.569–0.674, p < 0.001, and moderate correlations between IMTP force-time characteristics (excluding force at 100 ms and RSImod (ρ = 0.389–0.449, p = 0.013–0.050 were observed. Only force at 250 ms demonstrated a statistically significant moderate correlation with CMJ height (ρ = 0.346, p = 0.016 and no statistically significant associations were observed between IMTP force-time characteristics and SJ height. Stronger athletes (top 10 demonstrated statistically significantly greater CMJ heights, RSImods, and PCs (p ≤ 0.004, g = 1.32–1.89 compared to weaker (bottom 10 athletes, but no differences in SJ height were observed (p = 0.871, g = 0.06. These findings highlight that the ability to apply rapidly high levels of force in short time intervals is integral for PC, CMJ height, and reactive strength.

INFLUENCE OF POLYMERIC-DISPERSED REINFORCEMENT ADDITIVES ON THE PERFORMANCE CHARACTERISTICS OF ASPHALT CONCRETE

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Chernov Sergey Anatolevych

2017-07-01

Full Text Available The technique and results of the studies of the influence of a polymeric-dispersed reinforcement additive on the performance characteristics of road hot asphalt concrete, namely, its resistance to fatigue failures, rutting and development of residual deformation are described. It is shown that the proposed method of modification of asphalt-concrete mixtures ensures an increase in the durability of layers of pavement road surface.

South African exporter performance: new research into firm-specific and market characteristics

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Christopher May

2012-05-01

Full Text Available The export marketing performance of any firm is influenced by a multitude of different factors. Given the multi-faceted nature of the export market, this research study investigated specific factors such as how firm-specific characteristics, product characteristics, market characteristics and export marketing strategies impact on the export marketing performance of South African manufacturing firms. Some of the findings of this research study indicated that firm size, investment commitment and careful planning, as firm-specific characteristics, had a significant influence on export marketing performance. The relationship between export experience and export marketing performance was insignificant. The degree of pricing adaptation and product adaptation had a significant effect on export marketing performance, while this was not the case with respect to the degree of promotion adaptation and distributor support.

Linear source approximation scheme for method of characteristics

International Nuclear Information System (INIS)

Tang Chuntao

2011-01-01

Method of characteristics (MOC) for solving neutron transport equation based on unstructured mesh has already become one of the fundamental methods for lattice calculation of nuclear design code system. However, most of MOC codes are developed with flat source approximation called step characteristics (SC) scheme, which is another basic assumption for MOC. A linear source (LS) characteristics scheme and its corresponding modification for negative source distribution were proposed. The OECD/NEA C5G7-MOX 2D benchmark and a self-defined BWR mini-core problem were employed to validate the new LS module of PEACH code. Numerical results indicate that the proposed LS scheme employs less memory and computational time compared with SC scheme at the same accuracy. (authors)

Classification of methods for measuring current-voltage characteristics of semiconductor devices

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Iermolenko Ia. O.

2014-06-01

Full Text Available It is shown that computer systems for measuring current-voltage characteristics are very important for semiconductor devices production. The main criteria of efficiency of such systems are defined. It is shown that efficiency of such systems significantly depends on the methods for measuring current-voltage characteristics of semiconductor devices. The aim of this work is to analyze existing methods for measuring current-voltage characteristics of semiconductor devices and to create the classification of these methods in order to specify the most effective solutions in terms of defined criteria. To achieve this aim, the most common classifications of methods for measuring current-voltage characteristics of semiconductor devices and their main disadvantages are considered. Automated and manual, continuous, pulse, mixed, isothermal and isodynamic methods for measuring current-voltage characteristics are analyzed. As a result of the analysis and generalization of existing methods the next classification criteria are defined: the level of automation, the form of measurement signals, the condition of semiconductor device during the measurements, and the use of mathematical processing of the measurement results. With the use of these criteria the classification scheme of methods for measuring current-voltage characteristics of semiconductor devices is composed and the most effective methods are specified.

Structural Model for the Effects of Environmental Elements on the Psychological Characteristics and Performance of the Employees of Manufacturing Systems.

Science.gov (United States)

Realyvásquez, Arturo; Maldonado-Macías, Aidé Aracely; García-Alcaraz, Jorge; Cortés-Robles, Guillermo; Blanco-Fernández, Julio

2016-01-05

This paper analyzes the effects of environmental elements on the psychological characteristics and performance of employees in manufacturing systems using structural equation modeling. Increasing the comprehension of these effects may help optimize manufacturing systems regarding their employees' psychological characteristics and performance from a macroergonomic perspective. As the method, a new macroergonomic compatibility questionnaire (MCQ) was developed and statistically validated, and 158 respondents at four manufacture companies were considered. Noise, lighting and temperature, humidity and air quality (THAQ) were used as independent variables and psychological characteristics and employees' performance as dependent variables. To propose and test the hypothetical causal model of significant relationships among the variables, a data analysis was deployed. Results found that the macroergonomic compatibility of environmental elements presents significant direct effects on employees' psychological characteristics and either direct or indirect effects on the employees' performance. THAQ had the highest direct and total effects on psychological characteristics. Regarding the direct and total effects on employees' performance, the psychological characteristics presented the highest effects, followed by THAQ conditions. These results may help measure and optimize manufacturing systems' performance by enhancing their macroergonomic compatibility and quality of life at work of the employees.

Evaluation of the productive performance characteristics of red ...

African Journals Online (AJOL)

Evaluation of the productive performance characteristics of red tilapia ( Oreochromis sp.) injected with shark DNA into skeletal muscles and maintained diets containing different levels of probiotic and amino yeast.

Performance and carcass characteristics of Yankasa ram fed with ...

African Journals Online (AJOL)

Remember me ... and 50% maize and wheat offal mixture, were better when compared to the control (B0) and other test diet in terms of performance and carcass characteristics. ... Key words: Performance, carcass, biscuit waste, Yankasa ram.

Effects of Egg Incubation Methods on Locomotor Performances of Green Turtle (Chelonia mydas) Hatchlings

International Nuclear Information System (INIS)

Mohd Uzair Rusli; Joseph, J.; Hock-Chark, L.; Zainudin Bachol

2015-01-01

Effects of different incubation methods on crawling and swimming ability of post-emergence green sea turtle (Chelonia mydas) hatchlings at Cherating (Kuantan, Pahang) and Chagar Hutang (Pulau Redang, Terengganu) Turtle Sanctuary were analysed during nesting season in 2009. Mean crawling speed of hatchlings incubated in styrofoam box, beach hatchery and in situ were at 0.042±0.008, 0.136±0.026 and 0.143±0.045 m/ s, respectively. Crawling performance of hatclings from styrofoam box can be improved by keeping them for at least 48 h after their emergence. For swimming performance, all types of incubation methods showed significant differences in mean power-stroke rate during their early swimming effort ranging at 93-114 strokes/ min. However, no correlation was found between morphological characteristics of hatchlings and swimming performance. The results from this study may give different perspective in evaluating hatchling production, which is in terms of hatchling morphological characteristics and their locomotor performance. (author)

Growth performance, blood parameters and carcass characteristics ...

African Journals Online (AJOL)

This study was carried out with one hundred and twenty (120) day-old marshal chicks to investigate the effect of Maxigrain® enzyme supplementation of corn bran based diets on growth performance, carcass characteristics, haematology and serum biochemistry of broilers in an eight weeks experiment. Four experimental ...

Preconditioned characteristic boundary conditions based on artificial compressibility method for solution of incompressible flows

Science.gov (United States)

Hejranfar, Kazem; Parseh, Kaveh

2017-09-01

The preconditioned characteristic boundary conditions based on the artificial compressibility (AC) method are implemented at artificial boundaries for the solution of two- and three-dimensional incompressible viscous flows in the generalized curvilinear coordinates. The compatibility equations and the corresponding characteristic variables (or the Riemann invariants) are mathematically derived and then applied as suitable boundary conditions in a high-order accurate incompressible flow solver. The spatial discretization of the resulting system of equations is carried out by the fourth-order compact finite-difference (FD) scheme. In the preconditioning applied here, the value of AC parameter in the flow field and also at the far-field boundary is automatically calculated based on the local flow conditions to enhance the robustness and performance of the solution algorithm. The code is fully parallelized using the Concurrency Runtime standard and Parallel Patterns Library (PPL) and its performance on a multi-core CPU is analyzed. The incompressible viscous flows around a 2-D circular cylinder, a 2-D NACA0012 airfoil and also a 3-D wavy cylinder are simulated and the accuracy and performance of the preconditioned characteristic boundary conditions applied at the far-field boundaries are evaluated in comparison to the simplified boundary conditions and the non-preconditioned characteristic boundary conditions. It is indicated that the preconditioned characteristic boundary conditions considerably improve the convergence rate of the solution of incompressible flows compared to the other boundary conditions and the computational costs are significantly decreased.

3D large-scale calculations using the method of characteristics

International Nuclear Information System (INIS)

Dahmani, M.; Roy, R.; Koclas, J.

2004-01-01

An overview of the computational requirements and the numerical developments made in order to be able to solve 3D large-scale problems using the characteristics method will be presented. To accelerate the MCI solver, efficient acceleration techniques were implemented and parallelization was performed. However, for the very large problems, the size of the tracking file used to store the tracks can still become prohibitive and exceed the capacity of the machine. The new 3D characteristics solver MCG will now be introduced. This methodology is dedicated to solve very large 3D problems (a part or a whole core) without spatial homogenization. In order to eliminate the input/output problems occurring when solving these large problems, we define a new computing scheme that requires more CPU resources than the usual one, based on sweeps over large tracking files. The huge capacity of storage needed in some problems and the related I/O queries needed by the characteristics solver are replaced by on-the-fly recalculation of tracks at each iteration step. Using this technique, large 3D problems are no longer I/O-bound, and distributed CPU resources can be efficiently used. (author)

Psychosocial Characteristics of Optimum Performance in Isolated and Confined Environments (ICE)

Science.gov (United States)

Palinkas, Lawrence A.; Keeton, Kathryn E.; Shea, Camille; Leveton, Lauren B.

2010-01-01

The Behavioral Health and Performance (BHP) Element addresses human health risks in the NASA Human Research Program (HRP), including the Risk of Adverse Behavioral Conditions and the Risk of Psychiatric Disorders. BHP supports and conducts research to help characteristics and mitigate the Behavioral Medicine risk for exploration missions, and in some instances, current Flight Medical Operations. The Behavioral Health and Performance (BHP) Element identified research gaps within the Behavioral Medicine Risk, including Gap BMed6: What psychosocial characteristics predict success in an isolated, confined environment (ICE)? To address this gap, we conducted an extensive and exhaustive literature review to identify the following: 1) psychosocial characteristics that predict success in ICE environments; 2) characteristics that are most malleable; and 3) specific countermeasures that could enhance malleable characteristics.

Research of psychological characteristics and performance relativity of operators

International Nuclear Information System (INIS)

Fang Xiang; He Xuhong; Zhao Bingquan

2008-01-01

Based on the working tasks of an operator being taken into full consideration in this paper, on the one hand the table of measuring psychological characteristics is designed through the selection of special dimensions; on the other hand the table of performance appraisal is drafted through the choice of suitable standards of an operator. The paper analyzes the results of two aspects, sets relevant nuclear power plant operators as the research objective, and obtains the psychological characteristics and performance relativity of operators. The research can be as important and applied reference for the selection, evaluation and use of operators

Performance characteristics of long-track speed skaters: a literature review.

Science.gov (United States)

Konings, Marco J; Elferink-Gemser, Marije T; Stoter, Inge K; van der Meer, Dirk; Otten, Egbert; Hettinga, Florentina J

2015-04-01

Speed skating is an intriguing sport to study from different perspectives due to the peculiar way of motion and the multiple determinants for performance. This review aimed to identify what is known on (long-track) speed skating, and which individual characteristics determine speed skating performance. A total of 49 studies were included. Based on a multidimensional performance model, person-related performance characteristics were categorized in anthropometrical, technical, physiological, tactical, and psychological characteristics. Literature was found on anthropometry, technique, physiology, and tactics. However, psychological studies were clearly under-represented. In particular, the role of self-regulation might deserve more attention to further understand mechanisms relevant for optimal performance and for instance pacing. Another remarkable finding was that the technically/biomechanically favourable crouched skating technique (i.e. small knee and trunk angle) leads to a physiological disadvantage: a smaller knee angle may increase the deoxygenation of the working muscles. This is an important underlying aspect for the pacing tactics in speed skating. Elite speed skaters need to find the optimal balance between obtaining a fast start and preventing negative technical adaptations later on in the race by distributing their available energy over the race in an optimal way. More research is required to gain more insight into how this impacts on the processes of fatigue and coordination during speed skating races. This can lead to a better understanding on how elite speed skaters can maintain the optimal technical characteristics throughout the entire race, and how they can adapt their pacing to optimize all identified aspects that determine performance.

LEAKAGE CHARACTERISTICS OF BASE OF RIVERBANK BY SELF POTENTIAL METHOD AND EXAMINATION OF EFFECTIVENESS OF SELF POTENTIAL METHOD TO HEALTH MONITORING OF BASE OF RIVERBANK

Science.gov (United States)

Matsumoto, Kensaku; Okada, Takashi; Takeuchi, Atsuo; Yazawa, Masato; Uchibori, Sumio; Shimizu, Yoshihiko

Field Measurement of Self Potential Method using Copper Sulfate Electrode was performed in base of riverbank in WATARASE River, where has leakage problem to examine leakage characteristics. Measurement results showed typical S-shape what indicates existence of flow groundwater. The results agreed with measurement results by Ministry of Land, Infrastructure and Transport with good accuracy. Results of 1m depth ground temperature detection and Chain-Array detection showed good agreement with results of the Self Potential Method. Correlation between Self Potential value and groundwater velocity was examined model experiment. The result showed apparent correlation. These results indicate that the Self Potential Method was effective method to examine the characteristics of ground water of base of riverbank in leakage problem.

Hospital ownership, decisions on supervisory board characteristics, and financial performance.

Science.gov (United States)

Kuntz, Ludwig; Pulm, Jannis; Wittland, Michael

2016-01-01

Dynamic and complex transformations in the hospital market increase the relevance of good corporate governance. However, hospital performance and the characteristics of supervisory boards differ depending on ownership. The question therefore arises whether hospital owners can influence performance by addressing supervisory board characteristics. The objective of this study is to explain differences in the financial performance of hospitals with regard to ownership by studying the size and composition of supervisory boards. The AMADEUS database was used to collect information on hospital financial performance in 2009 and 2010. Business and quality reports, hospital websites, and data from health insurer were used to obtain information on hospital and board characteristics. The resulting sample consisted of 175 German hospital corporations. We utilized ANOVA and regression analysis to test a mediation hypothesis that investigated whether decisions regarding board size and composition were associated with financial performance and could explain performance differences. Financial performance and board size and composition depend on ownership. An increase in board size and greater politician participation were negatively associated with all five tested measures of financial performance. Furthermore, an increase in physician participation was positively associated with one dimension of financial performance, whereas one negative relationship was identified for nurse and economist participation. For clerics, no associations were found. Decisions concerning board size and composition are important as they relate to hospital financial performance. We contribute to existing research by showing that, in addition to board size and physician participation, the participation of other professionals can also influence financial performance.

Investigation of Material Performance Degradation for High-Strength Aluminum Alloy Using Acoustic Emission Method

Directory of Open Access Journals (Sweden)

Yibo Ai

2015-02-01

Full Text Available Structural materials damages are always in the form of micro-defects or cracks. Traditional or conventional methods such as micro and macro examination, tensile, bend, impact and hardness tests can be used to detect the micro damage or defects. However, these tests are destructive in nature and not in real-time, thus a non-destructive and real-time monitoring and characterization of the material damage is needed. This study is focused on the application of a non-destructive and real-time acoustic emission (AE method to study material performance degradation of a high-strength aluminum alloy of high-speed train gearbox shell. By applying data relative analysis and interpretation of AE signals, the characteristic parameters of materials performance were achieved and the failure criteria of the characteristic parameters for the material tensile damage process were established. The results show that the AE method and signal analysis can be used to accomplish the non-destructive and real-time detection of the material performance degradation process of the high-strength aluminum alloy. This technique can be extended to other engineering materials.

Insulation Coordination of Arcing Horns on HVDC Electrode Lines: Protection Performance Evaluation, Influence Factors and Improvement Method

Directory of Open Access Journals (Sweden)

Xiandong Li

2018-02-01

Full Text Available Arcing horns are widely used in high voltage overhead lines to protect insulator strings from being destroyed by the free burning arcs caused by lightening faults. In this paper, we focus on the insulation coordination of arcing horns on the electrode lines of a 5000 MW, ±800 kV high voltage direct current (HVDC system. The protection performance of arcing horns are determined by the characteristics of not only the external system but also the fault arc. Therefore, the behaviors and characteristics of long free burning arcs are investigated by the experiments at first. In order to evaluate the protection performance of arcing horns, the static stability criterion U-I characteristic method is introduced. The influence factors on the protection performance of arcing horns are analyzed theoretically. Finally, the improvement methods for the protection performance of arcing horns are proposed, and the diversified configuration strategy of arcing horns is recommended for cost saving.

Calculating the albedo characteristics by the method of transmission probabilities

International Nuclear Information System (INIS)

Lukhvich, A.A.; Rakhno, I.L.; Rubin, I.E.

1983-01-01

The possibility to use the method of transmission probabilities for calculating the albedo characteristics of homogeneous and heterogeneous zones is studied. The transmission probabilities method is a numerical method for solving the transport equation in the integrated form. All calculations have been conducted as a one-group approximation for the planes and rods with different optical thicknesses and capture-to-scattering ratios. Above calculations for plane and cylindrical geometries have shown the possibility to use the numerical method of transmission probabilities for calculating the albedo characteristics of homogeneous and heterogeneous zones with high accuracy. In this case the computer time consumptions are minimum even with the cylindrical geometry, if the interpolation calculation of characteristics is used for the neutrons of the first path

Accurate Point-of-Care Detection of Ruptured Fetal Membranes: Improved Diagnostic Performance Characteristics with a Monoclonal/Polyclonal Immunoassay

Directory of Open Access Journals (Sweden)

Linda C. Rogers

2016-01-01

Full Text Available Objective Accurate and timely diagnosis of rupture of membranes (ROM is imperative to allow for gestational age-specific interventions. This study compared the diagnostic performance characteristics between two methods used for the detection of ROM as measured in the same patient. Methods Vaginal secretions were evaluated using the conventional fern test as well as a point-of-care monoclonal/polyclonal immunoassay test (ROM Plus® in 75 pregnant patients who presented to labor and delivery with complaints of leaking amniotic fluid. Both tests were compared to analytical confirmation of ROM using three external laboratory tests. Diagnostic performance characteristics were calculated including sensitivity, specificity, positive predictive value (PPV, negative predictive value (NPV, and accuracy. Results Diagnostic performance characteristics uniformly favored ROM detection using the immunoassay test compared to the fern test: sensitivity (100% vs. 77.8%, specificity (94.8% vs. 79.3%, PPV (75% vs. 36.8%, NPV (100% vs. 95.8%, and accuracy (95.5% vs. 79.1%. Conclusions The point-of-care immunoassay test provides improved diagnostic accuracy for the detection of ROM compared to fern testing. It has the potential of improving patient management decisions, thereby minimizing serious complications and perinatal morbidity.

Reader characteristics linked to detection of pulmonary nodules on radiographs: ROC vs. JAFROC analyses of performance

Science.gov (United States)

Kohli, Akshay; Robinson, John W.; Ryan, John; McEntee, Mark F.; Brennan, Patrick C.

2011-03-01

The purpose of this study is to explore whether reader characteristics are linked to heightened levels of diagnostic performance in chest radiology using receiver operating characteristic (ROC) and jackknife free response ROC (JAFROC) methodologies. A set of 40 postero-anterior chest radiographs was developed, of which 20 were abnormal containing one or more simulated nodules, of varying subtlety. Images were independently reviewed by 12 boardcertified radiologists including six chest specialists. The observer performance was measured in terms of ROC and JAFROC scores. For the ROC analysis, readers were asked to rate their degree of suspicion for the presence of nodules by using a confidence rating scale (1-6). JAFROC analysis required the readers to locate and rate as many suspicious areas as they wished using the same scale and resultant data were used to generate Az and FOM scores for ROC and JAFROC analyses respectively. Using Pearson methods, scores of performance were correlated with 7 reader characteristics recorded using a questionnaire. JAFROC analysis showed that improved reader performance was significantly (pchest specialty (pchest radiographs (pchest readings per year (pchest radiographs (pchest specialty, hours reading per week and number of radiographs read per year. Also, JAFROC is a more powerful predictor of performance as compared to ROC.

Performance measurement of employee using an integrated 360° feedback system and AHP method: A case study of municipality

Directory of Open Access Journals (Sweden)

Younos Vakil Alroaia

2012-08-01

Full Text Available Performance measurement plays an essential role on accelerating the efficiency of any organization. There are literally different methods for measuring the relative performance of a particular unit and many of them are involved considering various criteria. In this paper, we propose 360° feedback system for performance measurement of all employees who work for municipality of the city of Tabas located in east part of Iran. The proposed model of this paper also uses hierarchical method to cluster different attributes based on various characteristics and implements analytical hierarchy process to find the relative importance of all items. The survey uses five personal characteristics including cognitive, technical, personal and human skills and for each major item, the proposed model considers various sub-criteria. The results indicate that technical and cognitive skills are the most important personal characteristics followed by human and personal characteristics. The results of this survey show that responsibility and quality of work are the most important employee characteristics.

Physics methods for calculating light water reactor increased performances

International Nuclear Information System (INIS)

Vandenberg, C.; Charlier, A.

1988-01-01

The intensive use of light water reactors (LWRs) has induced modification of their characteristics and performances in order to improve fissile material utilization and to increase their availability and flexibility under operation. From the conceptual point of view, adequate methods must be used to calculate core characteristics, taking into account present design requirements, e.g., use of burnable poison, plutonium recycling, etc. From the operational point of view, nuclear plants that have been producing a large percentage of electricity in some countries must adapt their planning to the need of the electrical network and operate on a load-follow basis. Consequently, plant behavior must be predicted and accurately followed in order to improve the plant's capability within safety limits. The Belgonucleaire code system has been developed and extensively validated. It is an accurate, flexible, easily usable, fast-running tool for solving the problems related to LWR technology development. The methods and validation of the two computer codes LWR-WIMS and MICROLUX, which are the main components of the physics calculation system, are explained

Haematological characteristics and performance of West African ...

African Journals Online (AJOL)

The effects of feeding crude petroleum contaminated forage on haematological characteristics and performance of 36 young West African Dwarf (WAD) goats was investigated in order to simulate the impact of real crude oil spillage on livestock and game. Graded levels (0.0, 1.5 and 3.0 g per kg forage) of stabilized “Bonny ...

Anthropometric, physiological and performance characteristics of elite team-handball players.

Science.gov (United States)

Chaouachi, Anis; Brughelli, Matt; Levin, Gregory; Boudhina, Nahla Ben Brahim; Cronin, John; Chamari, Karim

2009-01-15

The objective of this study was to provide anthropometric, physiological, and performance characteristics of an elite international handball team. Twenty-one elite handball players were tested and categorized according to their playing positions (goalkeepers, backs, pivots, and wings). Testing consisted of anthropometric and physiological measures of height, body mass, percentage body fat and endurance (VO(2max)), performance measures of speed (5, 10, and 30 m), strength (bench press and squat), unilateral and bilateral horizontal jumping ability, and a 5-jump horizontal test. Significant differences were found between player positions for some anthropometric characteristics (height and percentage body fat) but not for the physiological or performance characteristics. Strong correlations were noted between single leg horizontal jumping distances with 5-, 10-, and 30-m sprint times (r = 0.51-0.80; P team-handball players appear to be very similar. Single leg horizontal jumping distance could be a specific standardized test for predicting sprinting ability in elite handball players.

Neural Interfaces for Intracortical Recording: Requirements, Fabrication Methods, and Characteristics.

Science.gov (United States)

Szostak, Katarzyna M; Grand, Laszlo; Constandinou, Timothy G

2017-01-01

Implantable neural interfaces for central nervous system research have been designed with wire, polymer, or micromachining technologies over the past 70 years. Research on biocompatible materials, ideal probe shapes, and insertion methods has resulted in building more and more capable neural interfaces. Although the trend is promising, the long-term reliability of such devices has not yet met the required criteria for chronic human application. The performance of neural interfaces in chronic settings often degrades due to foreign body response to the implant that is initiated by the surgical procedure, and related to the probe structure, and material properties used in fabricating the neural interface. In this review, we identify the key requirements for neural interfaces for intracortical recording, describe the three different types of probes-microwire, micromachined, and polymer-based probes; their materials, fabrication methods, and discuss their characteristics and related challenges.

A Comparison Study between Two MPPT Control Methods for a Large Variable-Speed Wind Turbine under Different Wind Speed Characteristics

Directory of Open Access Journals (Sweden)

Dongran Song

2017-05-01

Full Text Available Variable speed wind turbines (VSWTs usually adopt a maximum power point tracking (MPPT method to optimize energy capture performance. Nevertheless, obtained performance offered by different MPPT methods may be affected by the impact of wind turbine (WT’s inertia and wind speed characteristics and it needs to be clarified. In this paper, the tip speed ratio (TSR and optimal torque (OT methods are investigated in terms of their performance under different wind speed characteristics on a 1.5 MW wind turbine model. To this end, the TSR control method based on an effective wind speed estimator and the OT control method are firstly presented. Then, their performance is investigated and compared through simulation test results under different wind speeds using Bladed software. Comparison results show that the TSR control method can capture slightly more wind energy at the cost of high component loads than the other one under all wind conditions. Furthermore, it is found that both control methods present similar trends of power reduction that is relevant to mean wind speed and turbulence intensity. From the obtained results, we demonstrate that, to further improve MPPT capability of large VSWTs, other advanced control methods using wind speed prediction information need to be addressed.

Fast computation of the characteristics method on vector computers

International Nuclear Information System (INIS)

Kugo, Teruhiko

2001-11-01

Fast computation of the characteristics method to solve the neutron transport equation in a heterogeneous geometry has been studied. Two vector computation algorithms; an odd-even sweep (OES) method and an independent sequential sweep (ISS) method have been developed and their efficiency to a typical fuel assembly calculation has been investigated. For both methods, a vector computation is 15 times faster than a scalar computation. From a viewpoint of comparison between the OES and ISS methods, the followings are found: 1) there is a small difference in a computation speed, 2) the ISS method shows a faster convergence and 3) the ISS method saves about 80% of computer memory size compared with the OES method. It is, therefore, concluded that the ISS method is superior to the OES method as a vectorization method. In the vector computation, a table-look-up method to reduce computation time of an exponential function saves only 20% of a whole computation time. Both the coarse mesh rebalance method and the Aitken acceleration method are effective as acceleration methods for the characteristics method, a combination of them saves 70-80% of outer iterations compared with a free iteration. (author)

Multidimensional performance characteristics and standard of performance in talented youth field hockey players : A longitudinal study

NARCIS (Netherlands)

Elferink-Gemser, Marije T.; Visscher, Chris; Lemmink, Koen A. P. M.; Mulder, Theo

2007-01-01

To identify performance characteristics that could help predict future elite field hockey players, we measured the anthropometric, physiological, technical, tactical, and psychological characteristics of 30 elite and 35 sub-elite youth players at the end of three consecutive seasons. The mean age of

Adaptive variational mode decomposition method for signal processing based on mode characteristic

Science.gov (United States)

Lian, Jijian; Liu, Zhuo; Wang, Haijun; Dong, Xiaofeng

2018-07-01

Variational mode decomposition is a completely non-recursive decomposition model, where all the modes are extracted concurrently. However, the model requires a preset mode number, which limits the adaptability of the method since a large deviation in the number of mode set will cause the discard or mixing of the mode. Hence, a method called Adaptive Variational Mode Decomposition (AVMD) was proposed to automatically determine the mode number based on the characteristic of intrinsic mode function. The method was used to analyze the simulation signals and the measured signals in the hydropower plant. Comparisons have also been conducted to evaluate the performance by using VMD, EMD and EWT. It is indicated that the proposed method has strong adaptability and is robust to noise. It can determine the mode number appropriately without modulation even when the signal frequencies are relatively close.

Study on evaluation methods for Rayleigh wave dispersion characteristic

Science.gov (United States)

Shi, L.; Tao, X.; Kayen, R.; Shi, H.; Yan, S.

2005-01-01

The evaluation of Rayleigh wave dispersion characteristic is the key step for detecting S-wave velocity structure. By comparing the dispersion curves directly with the spectra analysis of surface waves (SASW) method, rather than comparing the S-wave velocity structure, the validity and precision of microtremor-array method (MAM) can be evaluated more objectively. The results from the China - US joint surface wave investigation in 26 sites in Tangshan, China, show that the MAM has the same precision with SASW method in 83% of the 26 sites. The MAM is valid for Rayleigh wave dispersion characteristic testing and has great application potentiality for site S-wave velocity structure detection.

Job Characteristics, Work Involvement, and Job Performance of Public Servants

Science.gov (United States)

Johari, Johanim; Yahya, Khulida Kirana

2016-01-01

Purpose: The primary purpose of this study is to assess the predicting role of job characteristics on job performance. Dimensions in the job characteristics construct are skill variety, task identity, task significance, autonomy and feedback. Further, work involvement is tested as a mediator in the hypothesized link. Design/methodology/approach: A…

General performance characteristics of an irreversible ferromagnetic Stirling refrigeration cycle

International Nuclear Information System (INIS)

Lin, G.; Tegus, O.; Zhang, L.; Brueck, E.

2004-01-01

A new magnetic-refrigeration-cycle model using ferromagnetic materials as a cyclic working substance is set up, in which finite-rate heat transfer, heat leak and regeneration time are taken into account. On the basis of the thermodynamic properties of a ferromagnetic material, the general performance characteristics of the ferromagnetic Stirling refrigeration cycle are investigated and the effects of some key irreversibilities on the performance of the cycle are revealed. By using the optimal-control theory, the optimal relation between the coefficient of performance and the cooling rate is derived and some important performance bounds, e.g., the maximum cooling rate, the maximum coefficient of performance, are determined. Moreover, the optimal operating regions for cooling rate, coefficient of performance and the optimal operating temperatures of a cyclic working substance in the two heat-transfer processes are obtained. Furthermore, the influences of magnetization and magnetic field on the performance characteristics of the cycle are discussed. The results obtained here have general significance and can be deduced to the related ones of the Stirling refrigeration cycle using paramagnetic salt as a cyclic working substance

Nonlinear performance characteristics of flux-switching PM motors

NARCIS (Netherlands)

Ilhan, E.; Kremers, M.F.J.; Motoasca, T.E.; Paulides, J.J.H.; Lomonova, E.

2013-01-01

Nonlinear performance characteristics of 3-phase flux-switching permanent magnet motors (FSPM) are overviewed. These machines show advantages of a robust rotor structure and a high energy density. Research on the FSPM is predominated by topics such as modeling and machine comparison, with little

Electrical conductivity characteristic of TiO2 nanowires from hydrothermal method

International Nuclear Information System (INIS)

Othman, Mohd Azlishah; Amat, Noor Faridah; Ahmad, Badrul Hisham; Rajan, Jose

2014-01-01

One dimensional nanostructures of titanium dioxide (TiO 2 ) were synthesized via hydrothermal method by mixing TiO 2 as precursor in aqueous solution of NaOH as solvent. Then, heat and washing treatment was applied. Thus obtained wires had diameter ∼15 nm. TiO 2 nanowires will be used as a network in solar cell such dye-sensitized solar cell in order to improve the performance of electron movement in the device. To improve the performance of electron movement, the characteristics of TiO 2 nanowires have been analyses using field emission scanning electron microscopy (FESEM) analysis, x-ray diffractometer (XRD) analysis and brunauer emmett teller (BET) analysis. Finally, electrical conductivity of TiO 2 nanowires was determined by measuring the resistance of the TiO 2 nanowires paste on microscope glass.

Epistemic characteristics of Mapuche educational methods

Directory of Open Access Journals (Sweden)

Daniel Quilaqueo Rapimán

2016-01-01

Full Text Available This article presents the main epistemic characteristics of the educational methods used in Mapuche family education in communities in the Araucanía region, in Chile. The concept of epistemology is considered with regards to the production of practical, technical, symbolical and spiritual knowledge, as an epistemological critique of the monocultural nature of the school curriculum. The methodology used is qualitative research, based on Grounded Theory; the results shed light on the educational methods used in the learning and teaching of content relating to individuals and society, the setting in time and place, and spatial awareness. It is concluded that this kind of education is organized considering distinctive methods formulated on the basis of the rationale of Mapuche educational knowledge.

Performance characteristics of CdTe drift ring detector

Science.gov (United States)

Alruhaili, A.; Sellin, P. J.; Lohstroh, A.; Veeramani, P.; Kazemi, S.; Veale, M. C.; Sawhney, K. J. S.; Kachkanov, V.

2014-03-01

CdTe and CdZnTe material is an excellent candidate for the fabrication of high energy X-ray spectroscopic detectors due to their good quantum efficiency and room temperature operation. The main material limitation is associated with the poor charge transport properties of holes. The motivation of this work is to investigate the performance characteristics of a detector fabricated with a drift ring geometry that is insensitive to the transport of holes. The performance of a prototype Ohmic CdTe drift ring detector fabricated by Acrorad with 3 drift rings is reported; measurements include room temperature current voltage characteristics (IV) and spectroscopic performance. The data shows that the energy resolution of the detector is limited by leakage current which is a combination of bulk and surface leakage currents. The energy resolution was studied as a function of incident X-ray position with an X-ray microbeam at the Diamond Light Source. Different ring biasing schemes were investigated and the results show that by increasing the lateral field (i.e. the bias gradient across the rings) the active area, evaluated by the detected count rate, increased significantly.

Neural Interfaces for Intracortical Recording: Requirements, Fabrication Methods, and Characteristics

Directory of Open Access Journals (Sweden)

Katarzyna M. Szostak

2017-12-01

Full Text Available Implantable neural interfaces for central nervous system research have been designed with wire, polymer, or micromachining technologies over the past 70 years. Research on biocompatible materials, ideal probe shapes, and insertion methods has resulted in building more and more capable neural interfaces. Although the trend is promising, the long-term reliability of such devices has not yet met the required criteria for chronic human application. The performance of neural interfaces in chronic settings often degrades due to foreign body response to the implant that is initiated by the surgical procedure, and related to the probe structure, and material properties used in fabricating the neural interface. In this review, we identify the key requirements for neural interfaces for intracortical recording, describe the three different types of probes—microwire, micromachined, and polymer-based probes; their materials, fabrication methods, and discuss their characteristics and related challenges.

Study on transient hydrodynamic performance and cavitation characteristic of high-speed mixed-flow pump

International Nuclear Information System (INIS)

Chen, T; Liu, Y L; Sun, Y B; Wang, L Q; Wu, D Z

2013-01-01

In order to analyse the hydrodynamic performance and cavitation characteristic of a high-speed mixed-flow pump during transient operations, experimental studies were carried out. The transient hydrodynamic performance and cavitation characteristics of the mixed-flow pump with guide vane during start-up operation processes were tested on the pump performance test-bed. Performance tests of the pump were carried out under various inlet pressures and speed-changing operations. The real-time instantaneous external characteristics such as rotational speed, hydraulic head, flow rate, suction pressure and discharge pressure of the pump were measured. Based on the experimental results, the effect of fluid acceleration on the hydrodynamic performances and cavitation characteristics of the mixed-flow pump were analysed and evaluated

Job characteristics, flow, and performance: the moderating role of conscientiousness.

Science.gov (United States)

Demerouti, Evangelia

2006-07-01

The present article aims to show the importance of positive work-related experiences within occupational health psychology by examining the relationship between flow at work (i.e., absorption, work enjoyment, and intrinsic work motivation) and job performance. On the basis of the literature, it was hypothesized that (a) motivating job characteristics are positively related to flow at work and (b) conscientiousness moderates the relationship between flow and other ratings of (in-role and out-of-role) performance. The hypotheses were tested on a sample of 113 employees from several occupations. Results of moderated structural equation modeling analyses generally supported the hypotheses. Motivating job characteristics were predictive of flow, and flow predicted in-role and extra-role performance, for only conscientious employees.

RELATIONSHIPS BETWEEN MUSCLE FATIGUE CHARACTERISTICS AND MARKERS OF ENDURANCE PERFORMANCE

Directory of Open Access Journals (Sweden)

Martyn G. Morris

2008-12-01

Full Text Available The aim of this study was to examine the relationship of a range of in-vivo whole muscle characteristics to determinants of endurance performance. Eleven healthy males completed a cycle ergometer step test to exhaustion for the determination of the lactate threshold, gross mechanical efficiency, peak power and VO2max. On two separate occasions, contractile and fatigue characteristics of the quadriceps femoris were collected using a specially designed isometric strength-testing chair. Muscle fatigue was then assessed by stimulating the muscle for 3 minutes. Force, rate of force development and rates of relaxation were calculated at the beginning and end of the 3 minute protocol and examined for reliability and in relation to lactate threshold, VO2max, gross mechanical efficiency and peak power. Muscle characteristics, rate of force development and relaxation rate were demonstrated to be reliable measures. Force drop off over the 3 minutes (fatigue index was related to lactate threshold (r = -0.72 p < 0.01 but not to VO2max. The rate of force development related to the peak power at the end of the cycle ergometer test (r = -0.75 p < 0.01. Rates of relaxation did not relate to any of the performance markers. We found in-vivo whole muscle characteristics, such as the fatigue index and rate of force development, relate to specific markers of peripheral, but not to central, fitness components. Our investigation suggests that muscle characteristics assessed in this way is reliable and could be feasibly utilised to further our understanding of the peripheral factors underpinning performance

Analysis of External Treatment Methods and Technical Characteristics of External Treatment

Science.gov (United States)

Zhang, Rui; Miao, Mingsan; Bai, Ming

2018-01-01

Chinese medicine external therapy is a treatment method of Chinese medicine with Chinese characteristics. The effect of traditional Chinese medicine external treatment, convenient operation, external treatment and technology has great prospects for development. The traditional Chinese medicine external treatment method and technical characteristics were analyzed.

Design and performance characteristic analysis of servo valve-type water hydraulic poppet valve

International Nuclear Information System (INIS)

Park, Sung Hwan

2009-01-01

For water hydraulic system control, the flow or pressure control using high-speed solenoid valve controlled by PWM control method could be a good solution for prevention of internal leakage. However, since the PWM control of on-off valves cause extensive flow and pressure fluctuation, it is difficult to control the water hydraulic actuators precisely. In this study, the servo valve-type water hydraulic valve using proportional poppet as the main valve is designed and the performance characteristics of the servo valve-type water hydraulic valve are analyzed. Furthermore, it is demonstrated through experiments that a decline in control chamber pressure that follows the change of pilot flow is caused by the occurrence of cavitation around the proportional poppet, and that fundamental characteristics of the developed valve remain unaffected by the occurrence of cavitation

Characteristics and Performance of Existing Load Disaggregation Technologies

Energy Technology Data Exchange (ETDEWEB)

Mayhorn, Ebony T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sullivan, Greg P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Butner, Ryan S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hao, He [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Baechler, Michael C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-04-10

Non-intrusive load monitoring (NILM) or non-intrusive appliance load monitoring (NIALM) is an analytic approach to disaggregate building loads based on a single metering point. This advanced load monitoring and disaggregation technique has the potential to provide an alternative solution to high-priced traditional sub-metering and enable innovative approaches for energy conservation, energy efficiency, and demand response. However, since the inception of the concept in the 1980’s, evaluations of these technologies have focused on reporting performance accuracy without investigating sources of inaccuracies or fully understanding and articulating the meaning of the metrics used to quantify performance. As a result, the market for, as well as, advances in these technologies have been slowly maturing.To improve the market for these NILM technologies, there has to be confidence that the deployment will lead to benefits. In reality, every end-user and application that this technology may enable does not require the highest levels of performance accuracy to produce benefits. Also, there are other important characteristics that need to be considered, which may affect the appeal of NILM products to certain market targets (i.e. residential and commercial building consumers) and the suitability for particular applications. These characteristics include the following: 1) ease of use, the level of expertise/bandwidth required to properly use the product; 2) ease of installation, the level of expertise required to install along with hardware needs that impact product cost; and 3) ability to inform decisions and actions, whether the energy outputs received by end-users (e.g. third party applications, residential users, building operators, etc.) empower decisions and actions to be taken at time frames required for certain applications. Therefore, stakeholders, researchers, and other interested parties should be kept abreast of the evolving capabilities, uses, and characteristics

Performance characteristics of a Kodak computed radiography system.

Science.gov (United States)

Bradford, C D; Peppler, W W; Dobbins, J T

1999-01-01

The performance characteristics of a photostimulable phosphor based computed radiographic (CR) system were studied. The modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE) of the Kodak Digital Science computed radiography (CR) system (Eastman Kodak Co.-model 400) were measured and compared to previously published results of a Fuji based CR system (Philips Medical Systems-PCR model 7000). To maximize comparability, the same measurement techniques and analysis methods were used. The DQE at four exposure levels (30, 3, 0.3, 0.03 mR) and two plate types (standard and high resolution) were calculated from the NPS and MTF measurements. The NPS was determined from two-dimensional Fourier analysis of uniformly exposed plates. The presampling MTF was determined from the Fourier transform (FT) of the system's finely sampled line spread function (LSF) as produced by a narrow slit. A comparison of the slit type ("beveled edge" versus "straight edge") and its effect on the resulting MTF measurements was also performed. The results show that both systems are comparable in resolution performance. The noise power studies indicated a higher level of noise for the Kodak images (approximately 20% at the low exposure levels and 40%-70% at higher exposure levels). Within the clinically relevant exposure range (0.3-3 mR), the resulting DQE for the Kodak plates ranged between 20%-50% lower than for the corresponding Fuji plates. Measurements of the presampling MTF with the two slit types have shown that a correction factor can be applied to compensate for transmission through the relief edges.

CSR organisational taxonomy and job characteristics on performance: SME case studies

Directory of Open Access Journals (Sweden)

Thanalechumy Seeramulu

2017-05-01

Full Text Available This study examines the relationship between the CSR of organizational structure and job characteristics that influence employee job performance in the Malaysian context. Hence, it is important to study and analyze these two factors within the CSR taxonomy describing how these factors significantly influence employee job performance and to make recommendations how performance can be promoted among employees. This paper is based on a quantitative research approach where responses were gathered from the working population within Malaysia SMEs. The results from this study will help to point out the influence of these factors on the employee job performance and provide guidance to an organization for which these aspects should be emphasized in order to increase employees’ job performance to align performance with organizational goals. The analysis includes two dimensions of CSR taxonomy of organizational structure namely, centralization and formalization, as well as a set of five dimensions of job characteristics, such as task identity, task significance, skill variety, autonomy and feedback. The results of these findings show that job characteristics such as task significance, autonomy, feedback, and skill variety, positively influence job performance with autonomy having highest predictive power on job performance. The results of these findings reveal that the organizational structure does not contribute to the prediction of job performance even though a significant positive correlation exists between the structure and job performance in the Pearson correlation coefficient test. Therefore, this study will enrich the existing knowledge in the area of human resource management by focusing on job performance management.

The effect of environmental performance and accounting characteristics to earnings informativeness

Science.gov (United States)

Herawaty, V.

2018-01-01

The objective of this empirical study is to analyze the influence of environmental performance and company’s accounting characteristics to earnings informativeness proxied by earnings response coefficient (ERC) on manufacturing companies listed on Indonesia Stock Exchange and consistently follow the PROPER assessment in 2010-2014. One of the company’s considerations is to create the green environment reflecting its environmental measures, drawing investors to respond to the company’s environmental performance. The data were obtained from Indonesian Capital Market Directory (ICMD), the Indonesia Stock Exchange homepage, the company’s annual reports, the decree of the Minister of Environment. The samples used in this research are 27 go public manufacturing companies listed on Indonesia Stock Exchange that consistently follow the PROPER in 2010-2014. The sampling technique used was the purposive method. This research uses multiple regression analysis. The results show that the environmental performance and profitability have a positive influence to earnings informativeness, while leverage has a negative influence to earnings informativeness. Growth opportunities as a control variable has a positive effect on earnings informativeness. This research has proved that the environmental performance is crucial through observing the investors’ reaction in the capital market.

Growth performance, carcass and organ characteristics of growing ...

African Journals Online (AJOL)

An experiment was conducted at the Department of Animal Science teaching and research farm, Bayero University Kano, to evaluate the effect of feeding graded levels of Moringa oleifera leaf meal (MOLM) in diets on growth performance, carcass and organ characteristics of weaned rabbits. Twenty eight grower rabbits of ...

Experimental investigation on Performance and Emission Characteristics of J20, P20, N20 Biodiesel blends and Sound Characteristics of P20 Biodiesel blend Used in Single Cylinder Diesel Engine

Science.gov (United States)

rajasekar, R.; karthik, N.; Xavier, Goldwin

2017-05-01

Present work provides the effect of biodiesel blends and Sound Characteristics of P20 Biodiesel blend compared with Performance and emission Characteristics of diesel. Methods and analysis biodiesel blends was prepared by the Transesterification Process. Experiments were conducted in single cylinder constant speed direct injection diesel engine for various test fuels. Research is mainly focused on pongamia oil. It was observed that a 20% Pongamia oil blends and its properties were similar to diesel. The results showed that 20% Pongamia oil blends gave better performance, less in noise and emission compared with ester of Jatropha and neem oil blends. Hence Pongamia blends can be used in existing diesel engine without compromising the engine performance.

Study of two-stage turbine characteristic and its influence on turbo-compound engine performance

International Nuclear Information System (INIS)

Zhao, Rongchao; Zhuge, Weilin; Zhang, Yangjun; Yang, Mingyang; Martinez-Botas, Ricardo; Yin, Yong

2015-01-01

Highlights: • An analytical model was built to study the interactions between two turbines in series. • The impacts of HP VGT and LP VGT on turbo-compound engine performance were investigated. • The fuel reductions obtained by HP VGT at 1900 rpm and 1000 rpm are 3.08% and 7.83% respectively. • The optimum value of AR ranged from 2.0 to 2.5 as the turbo-compound engine speed decreases. - Abstract: Turbo-compounding is an effective way to recover waste heat from engine exhaust and reduce fuel consumption for internal combustion engine (ICE). The characteristics of two-stage turbine, including turbocharger turbine and power turbine, have significant effects on the overall performance of turbo-compound engine. This paper investigates the interaction between two turbines in a turbo-compound engine and its impact on the engine performance. Firstly an analytical model is built to investigate the effects of turbine equivalent flow area on the two-stage turbine characteristics, including swallowing capacity and load split. Next both simulation and experimental method are carried out to study the effects of high pressure variable geometry turbine (HP VGT), low pressure variable geometry turbine (LP VGT) and combined VGT on the engine overall performance. The results show that the engine performance is more sensitive to HP VGT compared with LP VGT at all the operation conditions, which is caused by the larger influences of HP VGT on the total expansion ratio and engine air–fuel ratio. Using the HP VGT method, the fuel reductions of the turbo-compound engine at 1900 rpm and 1000 rpm are 3.08% and 7.83% respectively, in comparison with the baseline engine. The corresponding optimum values of AR are 2.0 and 2.5

CHARACTERISTICS OF MIRR METHOD IN EVALUATION OF INVESTMENT PROJECTS' EFFECTIVENESS

OpenAIRE

P. Kukhta

2014-01-01

There were analyzed characteristics of the Modified Internal Rate of Return method in the evaluation of investment projects, restrictions connected with its application, advantages and disadvantages compared with indicators of the original Internal Rate of Return and Net Present Value for projects with certain baseline characteristics. It was determined opportunities to adapt the method of Modified Internal Rate of Return to alternative computational approaches of the project cash flows evalu...

On the integration scheme along a trajectory for the characteristics method

International Nuclear Information System (INIS)

Le Tellier, Romain; Hebert, Alain

2006-01-01

The issue of the integration scheme along a trajectory which appears for all tracking-based transport methods is discussed from the point of view of the method of characteristics. The analogy with the discrete ordinates method in slab geometry is highlighted along with the practical limitation in transposing high-order S N schemes to a trajectory-based method. We derived an example of such a transposition starting from the linear characteristic scheme. This new scheme is compared with the standard flat-source approximation of the step characteristic scheme and with the diamond differencing scheme. The numerical study covers a 1D analytical case, 2D one-group critical and fixed-source benchmarks and finally a realistic multigroup calculation on a BWR-MOX assembly

A method of network topology optimization design considering application process characteristic

Science.gov (United States)

Wang, Chunlin; Huang, Ning; Bai, Yanan; Zhang, Shuo

2018-03-01

Communication networks are designed to meet the usage requirements of users for various network applications. The current studies of network topology optimization design mainly considered network traffic, which is the result of network application operation, but not a design element of communication networks. A network application is a procedure of the usage of services by users with some demanded performance requirements, and has obvious process characteristic. In this paper, we first propose a method to optimize the design of communication network topology considering the application process characteristic. Taking the minimum network delay as objective, and the cost of network design and network connective reliability as constraints, an optimization model of network topology design is formulated, and the optimal solution of network topology design is searched by Genetic Algorithm (GA). Furthermore, we investigate the influence of network topology parameter on network delay under the background of multiple process-oriented applications, which can guide the generation of initial population and then improve the efficiency of GA. Numerical simulations show the effectiveness and validity of our proposed method. Network topology optimization design considering applications can improve the reliability of applications, and provide guidance for network builders in the early stage of network design, which is of great significance in engineering practices.

Hydrodynamic characteristics of high speed settling clarifiers by radiotracer method

International Nuclear Information System (INIS)

Griffith Martinez, J.; Flores Juan, P.; Cuesta Borges, J.; Damera Martinez, A.; Ramos Espinosa, K. A

2005-01-01

Results achieved in the evaluation of two high-speed settling cane juice Clarifiers, one denominated ICINAZ The Express and the other one with Low Residence Time (BTR), both located at the sugar factory Orlando Gonzalez employing the well established radiotracer method (Tc-99m) are presented. Several trials performed at the two Clarifiers demonstrated that the one identified as BTR was capable to assimilate the whole flow capacity of the factory with adequate characteristic of the pattern flux and residence time in the environment of 1 hour. In the other side, ICINAZ The Express Clarifier could only work at relative low flow capacity of the factory with residence time closely to the two hours and achieving occasionally a pattern flux seriously affected by fluctuations in the milling process. The radiotracer method was able to detect certain differences between the two clear juice outlet of the BTR Clarifier, probably due some problems in the construction of this equipment

PERFORMANCE CHARACTERISTIC MEMS-BASED IMUs FOR UAVs NAVIGATION

Directory of Open Access Journals (Sweden)

H. A. Mohamed

2015-08-01

Full Text Available Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK, and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS signal outage.

Performance Characteristic Mems-Based IMUs for UAVs Navigation

Science.gov (United States)

Mohamed, H. A.; Hansen, J. M.; Elhabiby, M. M.; El-Sheimy, N.; Sesay, A. B.

2015-08-01

Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs) are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS) or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK), and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS) signal outage.

CHARACTERISTICS OF MIRR METHOD IN EVALUATION OF INVESTMENT PROJECTS' EFFECTIVENESS

Directory of Open Access Journals (Sweden)

P. Kukhta

2014-09-01

Full Text Available There were analyzed characteristics of the Modified Internal Rate of Return method in the evaluation of investment projects, restrictions connected with its application, advantages and disadvantages compared with indicators of the original Internal Rate of Return and Net Present Value for projects with certain baseline characteristics. It was determined opportunities to adapt the method of Modified Internal Rate of Return to alternative computational approaches of the project cash flows evaluation.

Performance and Carcass Characteristics of Broiler Finisher Birds ...

African Journals Online (AJOL)

Sixty (60) 4 weeks old Anak broiler strain were subjected to 28 days feeding trial at the Poultry Unit of the Teaching and Research Farm, Evan Enwerem, Owerri, Nigeria, to determine the dietary effect of pineapple wine sediment (PWSM) on their performance and carcass characteristics. The birds were divided into four ...

Performance characteristics of proximity focused ultraviolet image converters

Science.gov (United States)

Williams, J. T.; Feibelman, W. A.

1973-01-01

Performance characteristics of Bendix type BX 8025-4522 proximity focused image tubes for UV to visible light conversion are presented. Quantum efficiency, resolution, background, geometric distortion, and environmental test results are discussed. The converters use magnesium fluoride input windows with Cs-Te photocathodes and P-11 phosphors on fiber optic output windows.

Computer Drawing Method for Operating Characteristic Curve of PV Power Plant Array Unit

Science.gov (United States)

Tan, Jianbin

2018-02-01

According to the engineering design of large-scale grid-connected photovoltaic power stations and the research and development of many simulation and analysis systems, it is necessary to draw a good computer graphics of the operating characteristic curves of photovoltaic array elements and to propose a good segmentation non-linear interpolation algorithm. In the calculation method, Component performance parameters as the main design basis, the computer can get 5 PV module performances. At the same time, combined with the PV array series and parallel connection, the computer drawing of the performance curve of the PV array unit can be realized. At the same time, the specific data onto the module of PV development software can be calculated, and the good operation of PV array unit can be improved on practical application.

Improved inference in the evaluation of mutual fund performance using panel bootstrap methods

OpenAIRE

Blake, David; Caulfield, Tristan; Ioannidis, Christos; Tonks, I P

2014-01-01

Two new methodologies are introduced to improve inference in the evaluation of mutual fund performance against benchmarks. First, the benchmark models are estimated using panel methods with both fund and time effects. Second, the non-normality of individual mutual fund returns is accounted for by using panel bootstrap methods. We also augment the standard benchmark factors with fund-specific characteristics, such as fund size. Using a dataset of UK equity mutual fund returns, we find that fun...

Influence of prey body characteristics and performance on predator selection.

Science.gov (United States)

Holmes, Thomas H; McCormick, Mark I

2009-03-01

At the time of settlement to the reef environment, coral reef fishes differ in a number of characteristics that may influence their survival during a predatory encounter. This study investigated the selective nature of predation by both a multi-species predator pool, and a single common predator (Pseudochromis fuscus), on the reef fish, Pomacentrus amboinensis. The study focused on the early post-settlement period of P. amboinensis, when mortality, and hence selection, is known to be highest. Correlations between nine different measures of body condition/performance were examined at the time of settlement, in order to elucidate the relationships between different traits. Single-predator (P. fuscus) choice trials were conducted in 57.4-l aquaria with respect to three different prey characteristics [standard length (SL), body weight and burst swimming speed], whilst multi-species trials were conducted on open patch reefs, manipulating prey body weight only. Relationships between the nine measures of condition/performance were generally poor, with the strongest correlations occurring between the morphological measures and within the performance measures. During aquaria trials, P. fuscus was found to be selective with respect to prey SL only, with larger individuals being selected significantly more often. Multi-species predator communities, however, were selective with respect to prey body weight, with heavier individuals being selected significantly more often than their lighter counterparts. Our results suggest that under controlled conditions, body length may be the most important prey characteristic influencing prey survival during predatory encounters with P. fuscus. In such cases, larger prey size may actually be a distinct disadvantage to survival. However, these relationships appear to be more complex under natural conditions, where the expression of prey characteristics, the selectivity fields of a number of different predators, their relative abundance, and

Mechanical/structural performance test method of a spacer grid

International Nuclear Information System (INIS)

Yoon, Kyung Ho

2000-06-01

The spacer grid is one of the main structural components in the fuel assembly, which supports the fuel rods, guides cooling water, and protects the system from an external impact load, such as earthquakes. In order to develop the spacer grid with the high mechanical performance, the mechanical and structural properties of the spacer grids must be extensively examined while designing it. In this report, the mechanical/structural test methods, i.e. the characteristic test of a spacer grid spring or dimple, static buckling test of a partial or full size spacer grid and dynamic impact test of them are described. The characteristic test of a spacer grid spring or dimple is accomplished with universal tensile test machine, a specimen is fixed with test fixture and then applied compressive load. The characteristic test data is saved at loading and unloading event. The static buckling test of a partial or full size spacer grid is executed with the same universal tensile testing machine, a specimen is fixed between cross-heads and then applied the compressive load. The buckling strength is decided the maximum strength at load vs. displacement curve. The dynamic impact test of a partial or full size spacer grid is performed with pendulum type impact machine and free fall shock test machine, a specimen is fixed with test fixture and then applied the impact load by impact hammer. Specially, the pendulum type impact test machine is also possible under the operating temperature because a furnace is separately attached with test machine

Wu’s Characteristic Set Method for SystemVerilog Assertions Verification

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Xinyan Gao

2013-01-01

Full Text Available We propose a verification solution based on characteristic set of Wu’s method towards SystemVerilog assertion checking over digital circuit systems. We define a suitable subset of SVAs so that an efficient polynomial modeling mechanism for both circuit descriptions and assertions can be applied. We present an algorithm framework based on the algebraic representations using characteristic set of polynomial system. This symbolic algebraic approach is a useful supplement to the existent verification methods based on simulation.

How Partner Characteristics Can Affect Performance of Alliances with Different Time Frames?

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Seyed Hossein JALALI

2017-11-01

Full Text Available Firms increasingly adopt cooperative strategies and form strategic alliances with foreign partners to be prosperous in entering to international market. Most of scholars have typically focused on generic, conceptual models for alliances partner selection, addressing only limited dimensions of the partner characteristics. This paper presents a new empirical framework that considering the effect of partner characteristics on export performance of alliances, in the case of short/mediumterm alliances and long-term ones. The study explores the effective partner characteristics for each type of alliances based on a sample of 540 alliances which rooted in East European region and also, have at least one Iranian partner. The findings stress the differences between varied partner characteristics in short/medium-term and long-term alliances. More specifically, results introduce a framework that addresses certain and specific partner characteristics to improve the export performance of alliances, due to the time frame of strategic alliances.

The Influence of Top Management Team Characteristics on BPD Performance (P.155-166

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Joy Elly Tulung

2017-01-01

Full Text Available Based on ”upper echelons theory”, this paper investigates the relation between top management team composition and BPD performance. For top management team characteristics, we employ age, level of education, background of education, gender, and functional background, while for measured the BPD performance we employ return on asset (ROA, return on equity (ROE, capital adequacy ratio (CAR, net interest margin (NIM, loan to deposit ratio (LDR, non-performing loan (NPL and operation expenses to operation income (BOPO. The results show that all characteristics have positive significant influences on BPD performance.Keywords: Top Management Team,BPD Performance, Upper Echelons Theory 

A Modeling of BWR-MOX assemblies based on the characteristics method combined with advanced self-shielding models

International Nuclear Information System (INIS)

Le Tellier, R.; Hebert, A.; Le Tellier, R.; Santamarina, A.; Litaize, O.

2008-01-01

Calculations based on the characteristics method and different self-shielding models are presented for 9 x 9 boiling water reactor (BWR) assemblies fully loaded with mixed-oxide (MOX) fuel. The geometry of these assemblies was recovered from the BASALA experimental program. We have focused our study on three configurations simulating the different voiding conditions that an assembly can undergo in a BWR pressure vessel. A parametric study was carried out with respect to the spatial discretization, the tracking parameters, and the anisotropy order. Comparisons with Monte Carlo calculations in terms of k eff , radiative capture, and fission rates were performed to validate the computational tools. The results are in good agreement between the stochastic and deterministic approaches. The mutual self-shielding model recently introduced within the framework of the Ribon extending self-shielding method appears to be useful for this type of assemblies. Indeed, in the calculation of these MOX benchmarks, the overlapping of resonances, especially between 238 U and 240 Pu, plays an important role due to the spectral strengthening of the flux as the voiding percentage is increased. The method of characteristics is shown to be adequate to perform accurate calculations handling a fine spatial discretization. (authors)

Performance and ileal characteristics of finishing broilers fed diets ...

African Journals Online (AJOL)

An experiment was conducted to evaluate the effect of prebiotics supplemented diets on performance characteristics and gut morphology of broiler chickens. The study involved 320 day-old Anak broiler chicks, used to assess the utilization of prebiotics [Mannose oligosaccharides (MOS) and Lactose oligosaccharides ...

Parametric study of geohydrologic performance characteristics for nuclear-waste repositories

International Nuclear Information System (INIS)

Bailey, C.E.; Marine, I.W.

1981-01-01

Purpose of this study was to present geohydrologic information in graphical form covering a wide range of parameters to aid in determining site specifications based on functional criteria. Graphs of the major performance characteristics that influence the transport of radionuclides from a repository to the biosphere by groundwater were developed. The major characteristics addressed are radioactive decay, leach rate, hydraulic conductivity, porosity, groundwater gradient, hydrodynamic dispersion, ion exchange, and distance to the biosphere

Standard Test Method for Electrical Performance of Concentrator Terrestrial Photovoltaic Modules and Systems Under Natural Sunlight

CERN Document Server

American Society for Testing and Materials. Philadelphia

2009-01-01

1.1 This test method covers the determination of the electrical performance of photovoltaic concentrator modules and systems under natural sunlight using a normal incidence pyrheliometer. 1.2 The test method is limited to module assemblies and systems where the geometric concentration ratio specified by the manufacturer is greater than 5. 1.3 This test method applies to concentrators that use passive cooling where the cell temperature is related to the air temperature. 1.4 Measurements under a variety of conditions are allowed; results are reported under a select set of concentrator reporting conditions to facilitate comparison of results. 1.5 This test method applies only to concentrator terrestrial modules and systems. 1.6 This test method assumes that the module or system electrical performance characteristics do not change during the period of test. 1.7 The performance rating determined by this test method applies only at the period of the test, and implies no past or future performance level. 1.8...

MULTICRITERIA METHODS IN PERFORMING COMPANIES’ RESULTS USING ELECTRONIC RECRUITING, CORPORATE COMMUNICATION AND FINANCIAL RATIOS

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Ivana Bilić

2011-02-01

Full Text Available Human resources represent one of the most important companies’ resources responsible in creation of companies’ competitive advantage. In search for the most valuable resources, companies use different methods. Lately, one of the growing methods is electronic recruiting, not only as a recruitment tool, but also as a mean of external communication. Additionally, in the process of corporate communication, companies nowadays use the electronic corporate communication as the easiest, the cheapest and the simplest form of business communication. The aim of this paper is to investigate relationship between three groups of different criteria; including main characteristics of performed electronic recruiting, corporate communication and selected financial performances. Selected companies were ranked separately by each group of criteria by usage of multicriteria decision making method PROMETHEE II. The main idea is to research whether companies which are the highest performers by certain group of criteria obtain the similar results regarding other group of criteria or performing results.

Performance and emissions characteristics of biodiesel from soybean oil

Energy Technology Data Exchange (ETDEWEB)

Canakci, M. [Kocaeli University, Izmit (Turkey). Faculty of Technical Education

2005-07-15

Biodiesel is an alternative diesel fuel that can be produced from renewable feedstocks such as vegetable oils, waste frying oils, and animal fats. It is an oxygenated, non-toxic, sulphur-free, biodegradable, and renewable fuel. Many engine manufacturers have included this fuel in their warranties since it can be used in diesel engines without significant modification. However, the fuel properties such as cetane number, heat of combustion, specific gravity, and kinematic viscosity affect the combustion, engine performance and emission characteristics. In this study, the engine performance and emissions characteristics of two different petroleum diesel fuels (No. 1 and No. 2 diesel fuels) and biodiesel from soybean oil and its 20 per cent blends with No. 2 diesel fuel were compared. The results showed that the engine performance of the neat biodiesel and its blend was similar to that of No. 2 diesel fuel with nearly the same brake fuel conversion efficiency, and slightly higher fuel consumption. CO{sub 2} emission for the biodiesel was slightly higher than for the No. 2 diesel fuel. Compared with diesel fuels, biodiesel produced lower exhaust emissions, except NO{sub x}. (author)

Prediction of multi performance characteristics of wire EDM process using grey ANFIS

Science.gov (United States)

Kumanan, Somasundaram; Nair, Anish

2017-09-01

Super alloys are used to fabricate components in ultra-supercritical power plants. These hard to machine materials are processed using non-traditional machining methods like Wire cut electrical discharge machining and needs attention. This paper details about multi performance optimization of wire EDM process using Grey ANFIS. Experiments are designed to establish the performance characteristics of wire EDM such as surface roughness, material removal rate, wire wear rate and geometric tolerances. The control parameters are pulse on time, pulse off time, current, voltage, flushing pressure, wire tension, table feed and wire speed. Grey relational analysis is employed to optimise the multi objectives. Analysis of variance of the grey grades is used to identify the critical parameters. A regression model is developed and used to generate datasets for the training of proposed adaptive neuro fuzzy inference system. The developed prediction model is tested for its prediction ability.

Relations between mental health team characteristics and work role performance.

Science.gov (United States)

Fleury, Marie-Josée; Grenier, Guy; Bamvita, Jean-Marie; Farand, Lambert

2017-01-01

Effective mental health care requires a high performing, interprofessional team. Among 79 mental health teams in Quebec (Canada), this exploratory study aims to 1) determine the association between work role performance and a wide range of variables related to team effectiveness according to the literature, and to 2) using structural equation modelling, assess the covariance between each of these variables as well as the correlation with other exogenous variables. Work role performance was measured with an adapted version of a work role questionnaire. Various independent variables including team manager characteristics, user characteristics, team profiles, clinical activities, organizational culture, network integration strategies and frequency/satisfaction of interactions with other teams or services were analyzed under the structural equation model. The later provided a good fit with the data. Frequent use of standardized procedures and evaluation tools (e.g. screening and assessment tools for mental health disorders) and team manager seniority exerted the most direct effect on work role performance. While network integration strategies had little effect on work role performance, there was a high covariance between this variable and those directly affecting work role performance among mental health teams. The results suggest that the mental healthcare system should apply standardized procedures and evaluation tools and, to a lesser extent, clinical approaches to improve work role performance in mental health teams. Overall, a more systematic implementation of network integration strategies may contribute to improved work role performance in mental health care.

Performance characteristics of broiler chicks fed kidney bean as ...

African Journals Online (AJOL)

An experiment was conducted to investigate the effect of replacing soybean meal and groundnut cake meal with cooked and decorticated kidney bean seed meals on the performance characteristics of broilers. One hundred and eighty day old broiler chicks of Anak strain were raised on six experimental diets.

Xeroradiography. Principles, characteristics and method indications

International Nuclear Information System (INIS)

Uemura, L.; Forni, S.S.; Abreu Neto, B.P.; Broccoli Neto, J.; Abilio, S.O.

1987-01-01

The xeroradiography is an entirely photoeletric process to obtain the radiographic image, employing a selenium plate instead of the conventional radiologic film. A revision of the physical principles and technical aspects of the method is presented, and the characteristics of xeroradiographic images are explained. The applications of xeroradiography include evaluation of breast, structures of the neck soft tissues tumors and some bone tumors for soft tissue components, foreign body detection in soft issues and visualization of the smaller skeletal structures of the extremeties. (Author) [pt

Study on Performance Shaping Factors (PSFs) Quantification Method in Human Reliability Analysis (HRA)

International Nuclear Information System (INIS)

Kim, Ar Ryum; Jang, Inseok Jang; Seong, Poong Hyun; Park, Jinkyun; Kim, Jong Hyun

2015-01-01

The purpose of HRA implementation is 1) to achieve the human factor engineering (HFE) design goal of providing operator interfaces that will minimize personnel errors and 2) to conduct an integrated activity to support probabilistic risk assessment (PRA). For these purposes, various HRA methods have been developed such as technique for human error rate prediction (THERP), simplified plant analysis risk human reliability assessment (SPAR-H), cognitive reliability and error analysis method (CREAM) and so on. In performing HRA, such conditions that influence human performances have been represented via several context factors called performance shaping factors (PSFs). PSFs are aspects of the human's individual characteristics, environment, organization, or task that specifically decrements or improves human performance, thus respectively increasing or decreasing the likelihood of human errors. Most HRA methods evaluate the weightings of PSFs by expert judgment and explicit guidance for evaluating the weighting is not provided. It has been widely known that the performance of the human operator is one of the critical factors to determine the safe operation of NPPs. HRA methods have been developed to identify the possibility and mechanism of human errors. In performing HRA methods, the effect of PSFs which may increase or decrease human error should be investigated. However, the effect of PSFs were estimated by expert judgment so far. Accordingly, in order to estimate the effect of PSFs objectively, the quantitative framework to estimate PSFs by using PSF profiles is introduced in this paper

COMPANY PERFORMANCE MEASUREMENT AND REPORTING METHODS

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Nicu Ioana Elena

2012-12-01

Full Text Available One of the priorities of economic research has been and remains the re-evaluation of the notion of performance and especially exploring and finding some indicators that would reflect as accurately as possible the subtleties of the economic entity. The main purpose of this paper is to highlight the main company performance measurement and reporting methods. Performance is a concept that raises many question marks concerning the most accurate or the best method of reporting the performance at the company level. The research methodology has aimed at studying the Romanian and foreign specialized literature dealing with the analyzed field, studying magazines specialized on company performance measurement. If the financial performance measurement indicators are considered to offer an accurate image of the situation of the company, the modern approach through non-financial indicators offers a new perspective upon performance measurement, which is based on simplicity. In conclusion, after the theoretical study, I have noticed that the methods of performance measurement, reporting and interpretation are various, the opinions regarding the best performance measurement methods are contradictive and the companies prefer resorting to financial indicators that still play a more important role in the consolidation of the company performance measurement than the non-financial indicators do.

Description and performance characteristics for the neutron Coincidence Collar for the verification of reactor fuel assemblies

International Nuclear Information System (INIS)

Menlove, H.O.

1981-08-01

An active neutron interrogation method has been developed for the measurement of 235 U content in fresh fuel assemblies. The neutron Coincidence Collar uses neutron interrogation with an AmLi neutron source and coincidence counting the induced fission reaction neutrons from the 235 U. This manual describes the system components, operation, and performance characteristics. Applications of the Coincidence Collar to PWR and BWR types of reactor fuel assemblies are described

Comparing the performance characteristics of CSF-TRUST and CSF-VDRL for syphilis: a cross-sectional study

OpenAIRE

Gu, Weiming; Yang, Yang; Wu, Lei; Yang, Sheng; Ng, Lai-King

2013-01-01

Objective In this study, we aimed to determine the performance characteristics of toluidine red unheated serum test on cerebrospinal fluids (CSF-TRUST) as compared to venereal disease research laboratory test on cerebrospinal fluids (CSF-VDRL) for laboratory the diagnosis of neurosyphilis. Design A cross-sectional study. Setting Sexually transmitted infections (STIs) clinics. Participants and methods CSF and serum samples were collected from 824 individual STD clinic patients who have syphili...

Prediction Method for the Complete Characteristic Curves of a Francis Pump-Turbine

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Wei Huang

2018-02-01

Full Text Available Complete characteristic curves of a pump-turbine are essential for simulating the hydraulic transients and designing pumped storage power plants but are often unavailable in the preliminary design stage. To solve this issue, a prediction method for the complete characteristics of a Francis pump-turbine was proposed. First, based on Euler equations and the velocity triangles at the runners, a mathematical model describing the complete characteristics of a Francis pump-turbine was derived. According to multiple sets of measured complete characteristic curves, explicit expressions for the characteristic parameters of characteristic operating point sets (COPs, as functions of a specific speed and guide vane opening, were then developed to determine the undetermined coefficients in the mathematical model. Ultimately, by combining the mathematical model with the regression analysis of COPs, the complete characteristic curves for an arbitrary specific speed were predicted. Moreover, a case study shows that the predicted characteristic curves are in good agreement with the measured data. The results obtained by 1D numerical simulation of the hydraulic transient process using the predicted characteristics deviate little from the measured characteristics. This method is effective and sufficient for a priori simulations before obtaining the measured characteristics and provides important support for the preliminary design of pumped storage power plants.

Production, performance, slaughter characteristics, and meat quality of Ziwuling wild crossbred pigs.

Science.gov (United States)

Chen, Guoshun; Sui, Yanan

2018-02-01

Wild boars, because of their large size and ability to survive adverse conditions, are usually used to cross with domestic breeds to improve the quality of domesticated pigs. This study aimed to investigate the growth performance, slaughter performance, and meat quality of Ziwuling crossbred pigs. Crossbred pigs in four groups (n = 8 per group, 4 boars and 4 sows, all aged 100 days), F 1 [wild × B (Bamei)], F 1  × B, F 1  × Y (Yorkshire), and F 1  × F 1 , were selected at a commercial pig farm. Growth performance, slaughter performance, and meat quality of these crossbred pigs were determined. Characteristics of fatty acids, amino acids, and longissimus muscle fiber in relation to growth, carcass, and meat quality traits were also investigated. Pigs in F 1 and F 1  × F 1 groups had lower average daily weight gain, water and storage loss rates, larger meat color score, higher muscle amino acid levels, larger muscle fiber diameter, and higher ratio of flavor amino acids to unsaturated fatty acids compared to other groups. Crossbred pigs with higher rate of wild boar's consanguinity could improve production performance, slaughter performance, and meat quality. Thus, crossbreeding wild pig with domestic breeds might be an effective method to improve meat quality and flavor.

Performance characteristics of plane-wall venturi-like reverse flow diverters

International Nuclear Information System (INIS)

Smith, G.V.; Counce, R.M.

1982-01-01

The results of an analytical and experimental study of plane-wall venturi-like reverse flow diverters (RFD) are presented. In general, the flow characteristics of the RFD are reasonably well predicted by the mathematical model of the RFD, although a divergence between theory and data is observed for the output characteristics in the reverse flow mode as the output impedance is reduced. Overall, the performance of these devices indicates their usefulness in fluid control and fluid power systems, such as displacement pumping systems

Managerial Characteristics and its Impact on Organizational Performance: Evidence from Syria

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Elias Milana

2015-06-01

Full Text Available This study aims to explore impact of managerial human capital in performance of a Syrian public organization, Directorate of Finance of province of Damascus, through use some of managerial characteristics are age, level of education, tenure and functional track. This study applied on a sample of 12 managers and 138 employees. The study reveals that there are no significant effect of age, level of education and functional track in performance of Directorate of Finance of province of Damascus, while there is a positive, strong and significant effect of tenure manager in organizational performance, which indicates that managerial characteristics almost irrelevant with performance of Directorate of Finance of the province of Damascus, and the public sector in general. Such results appear a need for efforts are invested in the formulation and implementation of human resource procedures and policies which can bring about effective change in behaviours and roles of the public managers and employees.

Differences in daily disposable circle lens performance characteristics

Directory of Open Access Journals (Sweden)

Schafer JM

2014-04-01

Full Text Available Jeffery M Schafer, William T Reindel, Marjorie J Rah, Osbert Chan, Lening Zhang Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: The purpose of this evaluation was to compare the performance characteristics of two cosmetically tinted contact lenses in the circle lens category that differ in lens design, lens material, and pigment print pattern: etafilcon A (1-Day Acuvue Define; Johnson & Johnson Vision Care and hilafilcon B (Naturelle; Bausch & Lomb Incorporated. Methods: Two hundred Asian subjects (400 eyes were enrolled in this 1-month parallel, bilateral, randomized study at ten investigative sites. Study lenses were dispensed at a screening/dispensing visit, and follow-up visits occurred at 2 weeks and 1 month. Lenses were worn on a daily disposable basis. Fit characteristics were evaluated at each visit, and slit-lamp evaluations were completed at each follow-up visit. Results: Of the 200 patients enrolled, 172 (344 eyes completed the study. The proportion of eyes with fully centered lenses was statistically significantly higher for the hilafilcon B group at the 2-week and 1-month visits, P<0.05. Over all visits, 0.6% of hilafilcon B eyes demonstrated incomplete corneal coverage, whereas for the etafilcon A group, 8.5% of eyes demonstrated incomplete corneal coverage and/or edge lift. The proportion of eyes with adequate lens movement was statistically significantly higher for the hilafilcon B group, P<0.05. Over all visits, none of the hilafilcon B eyes was reported to have excessive movement, whereas for etafilcon A lenses, 10.2% of eyes were reported to have excessive movement. Conclusions: Etafilcon A lenses were significantly less likely to be fully centered and significantly more likely to have incomplete corneal coverage and/or edge lift compared with the hilafilcon B lenses. Keywords: cosmetic contact lens, circle contact lens

Board Characteristics and Firm Performance: Evidence from Indonesia

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Athalia Ariati Hidayat

2015-12-01

Full Text Available This research examines the effect of board characteristics (comprising in different sized proportions: family commissioners, family directors, independent commissioners, ex-government officer commissioners, and board of commissioners size to firm performance. Using fixed-effects data panel regression, this research investigates 293 firms listed on the Indonesian Stock Exchange during 2008-2012. Firm performance is proxied by market measure (Tobin’s Q and accounting measure (ROA. The findings of this research suggest that the proportion of family commissioners and family directors have positive impact only to Tobin’s Q value, while the proportion of independent directors can increase both Tobin’s Q and ROA. On the other hand, this research finds that the proportion of ex-government officers in the board gives no impact to firm performance. This research also finds that the board size has U-shaped non-linear relationship with firm performance as proxied by Tobin’s Q and ROA.

Identification of a Multicriteria Decision-Making Model Using the Characteristic Objects Method

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Andrzej Piegat

2014-01-01

Full Text Available This paper presents a new, nonlinear, multicriteria, decision-making method: the characteristic objects (COMET. This approach, which can be characterized as a fuzzy reference model, determines a measurement standard for decision-making problems. This model is distinguished by a constant set of specially chosen characteristic objects that are independent of the alternatives. After identifying a multicriteria model, this method can be used to compare any number of decisional objects (alternatives and select the best one. In the COMET, in contrast to other methods, the rank-reversal phenomenon is not observed. Rank-reversal is a paradoxical feature in the decision-making methods, which is caused by determining the absolute evaluations of considered alternatives on the basis of the alternatives themselves. In the Analytic Hierarchy Process (AHP method and similar methods, when a new alternative is added to the original alternative set, the evaluation base and the resulting evaluations of all objects change. A great advantage of the COMET is its ability to identify not only linear but also nonlinear multicriteria models of decision makers. This identification is based not on a ranking of component criteria of the multicriterion but on a ranking of a larger set of characteristic objects (characteristic alternatives that are independent of the small set of alternatives analyzed in a given problem. As a result, the COMET is free of the faults of other methods.

Digital virtual flight testing and evaluation method for flight characteristics airworthiness compliance of civil aircraft based on HQRM

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Fan Liu

2015-02-01

Full Text Available In order to incorporate airworthiness requirements for flight characteristics into the entire development cycle of electronic flight control system (EFCS equipped civil aircraft, digital virtual flight testing and evaluation method based on handling qualities rating method (HQRM is proposed. First, according to HQRM, flight characteristics airworthiness requirements of civil aircraft in EFCS failure states are determined. On this basis, digital virtual flight testing model, comprising flight task digitized model, pilot controlling model, aircraft motion and atmospheric turbulence model, is used to simulate the realistic process of a pilot controlling an airplane to perform assigned flight tasks. According to the simulation results, flight characteristics airworthiness compliance of the airplane can be evaluated relying on the relevant regulations for handling qualities (HQ rating. Finally, this method is applied to a type of passenger airplane in a typical EFCS failure state, and preliminary conclusions concerning airworthiness compliance are derived quickly. The research results of this manuscript can provide important theoretical reference for EFCS design and actual airworthiness compliance verification of civil aircraft.

Numerical simulation of flow characteristics behind the aerodynamic performances on an airfoil with leading edge protuberances

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Ming Zhao

2017-01-01

Full Text Available This article presents a numerical investigation of the effects of leading-edge protuberances on airfoil stall and post-stall performance. An improved delayed detached eddy simulation (IDDES method was adopted. As a result, to clarify the effects of ‘bi-periodic’ phenomenon around stall region, it was found that the flow separation at troughs was the main inducement of aerodynamic lift degradation within pre-stall regime and the flow pattern where vortices diverged was predominant. It was also found that the variations in flow patterns led to the gentle stall process. Furthermore, to study the statistical characteristics of unsteady vortex shedding, corresponding spectrum characteristics were also analyzed from another perspective, suggesting that the vortex shedding frequency was higher where vortices converged. Eventually, the improved performances of tubercled airfoil within post-stall regime could be attributed to the strong streamwise vortices generated by the leading-edge protuberances. Deploying the methods of vortex dynamics, the generation and evolution of the streamwise vortices were depicted. It turned out that the primary and secondary vortices were induced by spanwise pressure gradient at airfoil surface; meanwhile, vortex stretching played a key role in primary vortex evolution, which initially enhanced the strength of vortices corresponding to the acceleration of streamwise velocity.

Generalized perturbation theory based on the method of cyclic characteristics

Energy Technology Data Exchange (ETDEWEB)

Assawaroongruengchot, M.; Marleau, G. [Institut de Genie Nucleaire, Departement de Genie Physique, Ecole Polytechnique de Montreal, 2900 Boul. Edouard-Montpetit, Montreal, Que. H3T 1J4 (Canada)

2006-07-01

A GPT algorithm for estimation of eigenvalues and reaction-rate ratios is developed for the neutron transport problems in 2D fuel assemblies with isotropic scattering. In our study the GPT formulation is based on the integral transport equations. The mathematical relationship between the generalized flux importance and generalized source importance functions is applied to transform the generalized flux importance transport equations into the integro-differential forms. The resulting adjoint and generalized adjoint transport equations are then solved using the method of cyclic characteristics (MOCC). Because of the presence of negative adjoint sources, a biasing/decontamination scheme is applied to make the generalized adjoint functions positive in such a way that it can be used for the multigroup re-balance technique. To demonstrate the efficiency of the algorithms, perturbative calculations are performed on a 17 x 17 PWR lattice. (authors)

Generalized perturbation theory based on the method of cyclic characteristics

International Nuclear Information System (INIS)

Assawaroongruengchot, M.; Marleau, G.

2006-01-01

A GPT algorithm for estimation of eigenvalues and reaction-rate ratios is developed for the neutron transport problems in 2D fuel assemblies with isotropic scattering. In our study the GPT formulation is based on the integral transport equations. The mathematical relationship between the generalized flux importance and generalized source importance functions is applied to transform the generalized flux importance transport equations into the integro-differential forms. The resulting adjoint and generalized adjoint transport equations are then solved using the method of cyclic characteristics (MOCC). Because of the presence of negative adjoint sources, a biasing/decontamination scheme is applied to make the generalized adjoint functions positive in such a way that it can be used for the multigroup re-balance technique. To demonstrate the efficiency of the algorithms, perturbative calculations are performed on a 17 x 17 PWR lattice. (authors)

Performance Characteristics of an Armature Voltage Controlled D.C. ...

African Journals Online (AJOL)

In this paper, the performance study of a separately excited d. c. motor whose speed is controlled by armature voltage variation is presented. Both the open loop and the closed loop steady state and transient characteristics are reported. The speed controllers considered in the closed loop mode are the proportional and the ...

Do the Managerial Characteristics of Schools Influence Their Performance?

Science.gov (United States)

Agasisti, Tommaso; Bonomi, Francesca; Sibiano, Piergiacomo

2012-01-01

Purpose: The purpose of this paper is to investigate the role of governance and managerial characteristics of schools. More specifically, the aim is to individuate the factors that are associated to higher schools' performances, as measured through student achievement. Design/methodology/approach: The research is conducted by means of a survey in…

Performance characteristics of an excimer laser (XeCl) with single ...

Indian Academy of Sciences (India)

2017-01-10

Jan 10, 2017 ... Performance characteristics of an excimer laser (XeCl) with single-stage magnetic ... the stress can increase the lifetime of the switches and ..... work. References. [1] Ying-Tung Chen, Kris Naessens, Roel Bates, Yunn-Shiuan.

Application of the Characteristic Basis Function Method Using CUDA

Directory of Open Access Journals (Sweden)

Juan Ignacio Pérez

2014-01-01

Full Text Available The characteristic basis function method (CBFM is a popular technique for efficiently solving the method of moments (MoM matrix equations. In this work, we address the adaptation of this method to a relatively new computing infrastructure provided by NVIDIA, the Compute Unified Device Architecture (CUDA, and take into account some of the limitations which appear when the geometry under analysis becomes too big to fit into the Graphics Processing Unit’s (GPU’s memory.

Characteristics explaining performance in downhill mountain biking.

Science.gov (United States)

Chidley, Joel B; MacGregor, Alexandra L; Martin, Caoimhe; Arthur, Calum A; Macdonald, Jamie H

2015-03-01

To identify physiological, psychological, and skill characteristics that explain performance in downhill (DH) mountain-bike racing. Four studies were used to (1) identify factors potentially contributing to DH performance (using an expert focus group), (2) develop and validate a measure of rider skill (using video analysis and expert judge evaluation), (3) evaluate whether physiological, psychological, and skill variables contribute to performance at a DH competition, and (4) test the specific contribution of aerobic capacity to DH performance. STUDY 1 identified aerobic capacity, handgrip endurance, anaerobic power, rider skill, and self-confidence as potentially important for DH. In study 2 the rider-skill measure displayed good interrater reliability. Study 3 found that rider skill and handgrip endurance were significantly related to DH ride time (β=-0.76 and -0.14, respectively; R2=.73), with exploratory analyses suggesting that DH ride time may also be influenced by self-confidence and aerobic capacity. Study 4 confirmed aerobic capacity as an important variable influencing DH performance (for a DH ride, mean oxygen uptake was 49±5 mL·kg(-1)·min(-1), and 90% of the ride was completed above the 1st ventilatory threshold). In order of importance, rider skill, handgrip endurance, self-confidence, and aerobic capacity were identified as variables influencing DH performance. Practically, this study provides a novel assessment of rider skill that could be used by coaches to monitor training and identify talent. Novel intervention targets to enhance DH performance were also identified, including self-confidence and aerobic capacity.

Operational characteristics, strategies and performance of foreign and demestic banks in India

OpenAIRE

Keshari, Pradeep Kumar

2013-01-01

This paper has tried to examine the relative characteristics and performance of foreign and domestic banks operating in India. A comparison of their characteristics undoubtedly suggest that foreign banks as a group differ significantly from domestic banks. It was also found that foreign banks enjoyed higher profitability than the domestic banks. The higher profitability of the former was a reflection of their particular operational characteristics, strategies and the favourable attitude of t...

The performance characteristics of the Philips Gemini PET/CT scanner

International Nuclear Information System (INIS)

O'Keefe, G.J.; Papenfuss, A.T.; Scott, A.M.; Rowe, C.C.

2002-01-01

Full text: The Department of Nuclear Medicine, Centre for PET at the ARMC is commissioning a next generation PET/CT scanner based on gadolinium silicic dioxide (GSO) crystal technology to replace the BGO crystal PET scanner that has been in operation since 1992. The Gemini PET/CT scanner is a fully 3D PET system which offers significantly increased resolution and sensitivity allowing wholebody scans in under 30 minutes. Until the late 90's, PET scanners were largely used with septa for neurological imaging and the performance characteristics of PET scanners were presented according to the NEMA-NU2-94 standard which specifically addresses the performance of PET scanners for neurological applications. PET is now largely used without septa for oncological imaging and as such, the NEMA-NU2-94 standard does not adequately reflect performance. The NEMA-NU2-2001 standard was designed to incorporate the effects of out-of-FOV activity and its contribution to performance by virtue of the increased scatter and randoms that result when performing wholebody scans without the use of septa. As part of the acceptance program of the Allegro/Gemini systems, the NEMA-NU2-2001 standard will be used to characterise the spatial resolution, sensitivity, randoms and scatter contributions and the Noise Equivalent Count rate (NECr). These results will be presented and compared with the ECAT 951/31R performance characteristics. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

Development of Numerical Technique to Analyze the Flow Characteristics of Porous Media Using Lattice Boltzmann Method

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyung Min [Kyonggi Univ., Suwon (Korea, Republic of)

2016-11-15

The performance of proton exchange membrane fuel cells (PEMFC) is strongly related to the water flow and accumulation in the gas diffusion layer (GDL) and catalyst layer. Understanding the behavior of fluid from the characteristics of the media is crucial for the improvement of the performance and design of the GDL. In this paper, a numerical method is proposed to calculate the design parameters of the GDL, i.e., permeability, tortuosity, and effective diffusivity. The fluid flow in a channel filled with randomly packed hard spheres is simulated to validate the method. The flow simulation was performed by lattice Boltzmann method with bounce back condition for the solid volume fraction in the porous media, with different values of porosities. Permeability, which affects the flow, was calculated from the average pressure drop and the velocity in the porous media. Tortuosity, calculated by the ratio the average path length of the randomly injected massless particles to the thickness of the porous media, and the resultant effective diffusivity were in good agreement with the theoretical model. The suggested method can be used to calculate the parameters of real GDL accurately without any modification.

Do positive psychological characteristics modify associations of physical performance with functional decline and institutionalization? Findings from the Longitudinal Aging Study Amsterdam

NARCIS (Netherlands)

Cooper, R.; Huisman, M.; Kuh, D; Deeg, D.J.H.

2011-01-01

Objectives. To investigate whether 3 positive psychological characteristics, related to sense of control, modify the associations of physical performance levels with subsequent functional decline and institutionalization. Method. One thousand five hundred and thirty-two men and women participating

Characteristics and performances of electronic personal dosemeters

International Nuclear Information System (INIS)

Aubert, B.

2002-01-01

The regulations have made obligation for 2 years to measure and analyse the amounts of radiations actually received during an operation. The whole of these measurements taken uninterrupted for an immediate reading is indicated like the operational dosimetry, which is carried out with the means of personal electronic dosemeters. This study analyses the legislation relating to this type of dosimetry as well as the requirements in medical environment, and presents an assessment of the characteristics and performances of the devices available on the French market at the beginning of 2002 starting from the information provided by the various manufacturers. (author)

Uncertainty characteristics of EPA's ground-water transport model for low-level waste performance assessment

International Nuclear Information System (INIS)

Yim, Man-Sung

1995-01-01

Performance assessment is an essential step either in design or in licensing processes to ensure the safety of any proposed radioactive waste disposal facilities. Since performance assessment requires the use of computer codes, understanding the characteristics of computer models used and the uncertainties of the estimated results is important. The PRESTO-EPA code, which was the basis of the Environmental Protection Agency's analysis for low-level-waste rulemaking, is widely used for various performance assessment activities in the country with no adequate information available for the uncertainty characteristics of the results. In this study, the groundwater transport model PRESTO-EPA was examined based on the analysis of 14 C transport along with the investigation of uncertainty characteristics

Unstructured characteristic method embedded with variational nodal method using domain decomposition techniques

Energy Technology Data Exchange (ETDEWEB)

Girardi, E.; Ruggieri, J.M. [CEA Cadarache (DER/SPRC/LEPH), 13 - Saint-Paul-lez-Durance (France). Dept. d' Etudes des Reacteurs; Santandrea, S. [CEA Saclay, Dept. Modelisation de Systemes et Structures DM2S/SERMA/LENR, 91 - Gif sur Yvette (France)

2005-07-01

This paper describes a recently-developed extension of our 'Multi-methods,multi-domains' (MM-MD) method for the solution of the multigroup transport equation. Based on a domain decomposition technique, our approach allows us to treat the one-group equation by cooperatively employing several numerical methods together. In this work, we describe the coupling between the Method of Characteristics (integro-differential equation, unstructured meshes) with the Variational Nodal Method (even parity equation, cartesian meshes). Then, the coupling method is applied to the benchmark model of the Phebus experimental facility (Cea Cadarache). Our domain decomposition method give us the capability to employ a very fine mesh in describing a particular fuel bundle with an appropriate numerical method (MOC), while using a much large mesh size in the rest of the core, in conjunction with a coarse-mesh method (VNM). This application shows the benefits of our MM-MD approach, in terms of accuracy and computing time: the domain decomposition method allows us to reduce the Cpu time, while preserving a good accuracy of the neutronic indicators: reactivity, core-to-bundle power coupling coefficient and flux error. (authors)

Unstructured characteristic method embedded with variational nodal method using domain decomposition techniques

International Nuclear Information System (INIS)

Girardi, E.; Ruggieri, J.M.

2005-01-01

This paper describes a recently-developed extension of our 'Multi-methods,multi-domains' (MM-MD) method for the solution of the multigroup transport equation. Based on a domain decomposition technique, our approach allows us to treat the one-group equation by cooperatively employing several numerical methods together. In this work, we describe the coupling between the Method of Characteristics (integro-differential equation, unstructured meshes) with the Variational Nodal Method (even parity equation, cartesian meshes). Then, the coupling method is applied to the benchmark model of the Phebus experimental facility (Cea Cadarache). Our domain decomposition method give us the capability to employ a very fine mesh in describing a particular fuel bundle with an appropriate numerical method (MOC), while using a much large mesh size in the rest of the core, in conjunction with a coarse-mesh method (VNM). This application shows the benefits of our MM-MD approach, in terms of accuracy and computing time: the domain decomposition method allows us to reduce the Cpu time, while preserving a good accuracy of the neutronic indicators: reactivity, core-to-bundle power coupling coefficient and flux error. (authors)

Facebook use, personality characteristics and academic performance: A correlational study

OpenAIRE

Sapsani, Georgia; Tselios, Nikolaos

2017-01-01

The present paper examines the relationship between the students personality, use of social media and their academic performance and engagement. In specific, the aim of this study is to examine the relationship of students facebook (fb) use and personality characteristics using the Big Five Personality Test with (a) student engagement, (b) time spent preparing for class, (c) time spent in co-curricular activities and (d) academic performance. Results illustrate that fb time was significantly ...

A general modeling method for I-V characteristics of geometrically and electrically configured photovoltaic arrays

International Nuclear Information System (INIS)

Liu Guangyu; Nguang, Sing Kiong; Partridge, Ashton

2011-01-01

Highlights: → A novel and general method is proposed for modeling PV arrays or modules. → A robust algorithm is used for the first time to improve the convergence to solution. → Auxiliary functions in other general methods are not compulsory in our method. → It is novel that geometric configuration is also incorporated. → A case study is performed to show the approach's advantages and unique features. - Abstract: A general method for modeling typical photovoltaic (PV) arrays and modules is proposed to find the exact current and voltage relationship of PV arrays or modules of geometrically and electrically different configurations. Nonlinear characteristic equations of electrical devices in solar array or module systems are numerically constructed without adding any virtual electrical components. Then, a robust damped Newton method is used to find exact I-V relationship of these general nonlinear equations, where the convergence is guaranteed. The model can deal with different mismatch effects such as different configurations of bypass diodes, and partial shading. Geometry coordinates of PV components are also considered to facilitate the modeling of the actual physical configuration. Simulation of a PV array with 48 modules, partially shaded by a concrete structure, is performed to verify the effectiveness and advantages of the proposed method.

An analytical method for the calculation of static characteristics of linear step motors for control rod drives in nuclear reactors

International Nuclear Information System (INIS)

Khan, S.H.; Ivanov, A.A.

1995-01-01

An analytical method for calculating static characteristics of linear dc step motors (LSM) is described. These multiphase passive-armature motors are now being developed for control rod drives (CRD) in large nuclear reactors. The static characteristics of such LSM is defined by the variation of electromagnetic force with armature displacement and it determines motor performance in its standing and dynamic modes of operation. The proposed analytical technique for calculating this characteristic is based on the permeance analysis method applied to phase magnetic circuits of LSM. Reluctances of various parts of phase magnetic circuit is calculated analytically by assuming probable flux paths and by taking into account complex nature of magnetic field distribution in it. For given armature positions stator and armature iron saturations are taken into account by an efficient iterative algorithm which gives fast convergence. The method is validated by comparing theoretical results with experimental ones which shows satisfactory agreement for small stator currents and weak iron saturation

Evaluation of the performance characteristic for mammography by using edge device

Energy Technology Data Exchange (ETDEWEB)

Kim, Ki Won [Dept. of Radiology, Kyung Hee University Hospital at Gang-dong, Seoul (Korea, Republic of); Choi, Jwan Woo [Dept. of Radiology, Asan Medical Center, Seoul (Korea, Republic of); Jeong, Hoi Woun [Dept. of Radiological Technology, The Baekseok Culture University, Cheonan (Korea, Republic of); Jang, Seo Goo [Dept. of Medical Science, The Soonchunhyang University, Asan (Korea, Republic of); Lee, Eul Kyu [Dept. of Radiology, Inje Paik University Hospital Jeo-dong, Seoul (Korea, Republic of); Son, Soon Yong [Dept. of Radiological Technology, The Wonkwang Health Science University, Iksan (Korea, Republic of); Son, Jin Hyun; Min, Jung Whan [Dept. of Radiological Technology, The Shingu University, Sungnam (Korea, Republic of)

2016-09-15

The purpose of this study was to evaluation of the performance characteristic for mammography by using edge device that mammography equipment improves essential in the correct diagnosis for the maintenance. We measured the modulation transfer function (MTF), the noise power spectrum (NPS), and the detective quantum efficiency (DQE) using the 61267 RQA-M2 based on commission standard international electro-technical commission (IEC). As a results, spatial resolution of dimensions tomo and lorad selenia mammography were maintained at 10 mm-1 and NPS and DQE including the low nyquist frequency indicated to 6.0 mm-1. Therefore, regularly QA of mammography system should be necessary. This study can be contribute to evaluate QA for performance characteristic of mammography of DDR system.

Performance Characteristics of Long-Track Speed Skaters : A Literature Review

NARCIS (Netherlands)

Konings, Marco J.; Elferink-Gemser, Marije T.; Stoter, Inge K.; van der Meer, Dirk; Otten, Egbert; Hettinga, Florentina J.

Speed skating is an intriguing sport to study from different perspectives due to the peculiar way of motion and the multiple determinants for performance. This review aimed to identify what is known on (long-track) speed skating, and which individual characteristics determine speed skating

The influence of system quality characteristics on health care providers’ performance: Empirical evidence from Malaysia

Directory of Open Access Journals (Sweden)

Mohd Idzwan Mohd Salleh

2016-11-01

Full Text Available Summary: Background: The Ministry of Health Malaysia initiated the total hospital information system (THIS as the first national electronic health record system for use in selected public hospitals across the country. Since its implementation 15 years ago, there has been the critical requirement for a systematic evaluation to assess its effectiveness in coping with the current system, task complexity, and rapid technological changes. The study aims to assess system quality factors to predict the performance of electronic health in a single public hospital in Malaysia. Methods: Non-probability sampling was employed for data collection among selected providers in a single hospital for two months. Data cleaning and bias checking were performed before final analysis in partial least squares-structural equation modeling. Results and conclusions: Convergent and discriminant validity assessments were satisfied the required criterions in the reflective measurement model. The structural model output revealed that the proposed adequate infrastructure, system interoperability, security control, and system compatibility were the significant predictors, where system compatibility became the most critical characteristic to influence an individual health care provider’s performance. The previous DeLone and McLean information system success models should be extended to incorporate these technological factors in the medical system research domain to examine the effectiveness of modern electronic health record systems. In this study, care providers’ performance was expected when the system usage fits with patients’ needs that eventually increased their productivity. Keywords: Electronic health records system, System quality characteristics, Care providers’ performance, Evaluation, Partial least squares-structural equation modeling

Performance Characteristic of Cold Recycled Mixture with Asphalt Emulsion and Chemical Additives

Directory of Open Access Journals (Sweden)

Shaowen Du

2015-01-01

Full Text Available Three types of chemical additives were used to modify asphalt emulsion recycled mixture. These chemical additives include composite Portland cement (CPC, hydrated lime (HL, and a combination of hydrated lime and ground-granulated blast-furnace slag (GGBF. The influence of different additives on the recycled mixture performance was investigated by volumetric and strength tests, moisture susceptibility test, rutting resistance test, and low temperature bending test. To better understand its performance characteristic, the microstructure images of the recycled mixture were observed by environmental scanning electron microscope (ESEM. Test results demonstrate that the performance improvement of the emulsion recycled mixture depends on the types and content of chemical additives. Several recommendations are presented for the selection of chemical materials. Based on ESEM image analysis, the interface bonding mechanism is proposed to explain the performance characteristic of the recycled mixture with asphalt emulsion and cementitious materials.

Board Characteristics and Accounting Performance in Banking Industry: The Indonesian Experience

Directory of Open Access Journals (Sweden)

Muhammad Agung Prabowo

2018-02-01

Full Text Available This paper examines the effect of board characteristics on accounting return in Indonesian banking industry. The conceptual framework borrows from agency theory claiming that board is held liable for monitoring responsibilities and that monitoring effectiveness will lead to higher corporate achievement. Yet the theory predicts that board characteristics matter in constituting firm performance. It is hypothesized that leadership structure, representation of independent directors, board size, and the rank of college board chairperson attended are necessary attributes enable the board to deliver better performance. The investigation is based on a dataset consisting of 83 banks during 2009-2015. Panel data analysis reveal that the proportion of independent directors, board leadership structure, and board size shows insignificant influence. The rank of universities the board chairperson graduated is found to have an impact on accounting earnings. The impact is robust after the type of controlling owners is taken into account. Yet the association between university rank and performance is more pronounced in the listed-banks.

Analysis of a MOX-UO2 interface by the method of characteristics

International Nuclear Information System (INIS)

Chetaine, A.; Erradi, L.; Sanchez, R.; Zmijarevic, I.; Aniel-Buchheit, S.

2005-01-01

In the last few years many studies have been done to improve the ability of core reactors (PWR and BWR) to burn Plutonium fuel, either in mixed UO 2 /MOX pattern or full MOX pattern. The analysis of a MOX-UO 2 interface with the method of characteristics has been carried out. Comparisons with Monte Carlo and collision-probability calculations show that our results are in good agreement with those obtained by reference methods and qualify the method of characteristic as a reliable technique for such calculations. (authors)

Performance characteristics of a quantum Diesel refrigeration cycle

International Nuclear Information System (INIS)

He Jizhou; Wang Hao; Liu Sanqiu

2009-01-01

The Diesel refrigeration cycle using an ideal quantum gas as the working substance is called quantum Diesel refrigeration cycle, which is different from Carnot, Ericsson, Brayton, Otto and Stirling refrigeration cycles. For ideal quantum gases, a corrected equation of state, which considers the quantum behavior of gas particles, is used instead of the classical one. The purpose of this paper is to investigate the effect of quantum gas as the working substance on the performance of a quantum Diesel refrigeration cycle. It is found that coefficients of performance of the cycle are not affected by the quantum degeneracy of the working substance, which is the same as that of the classical Diesel refrigeration cycle. However, the refrigeration load is different from those of the classical Diesel refrigeration cycle. Lastly, the influence of the quantum degeneracy on the performance characteristics of the quantum Diesel refrigeration cycle operated in different temperature regions is discussed

Characteristic Value Method of Well Test Analysis for Horizontal Gas Well

Directory of Open Access Journals (Sweden)

Xiao-Ping Li

2014-01-01

Full Text Available This paper presents a study of characteristic value method of well test analysis for horizontal gas well. Owing to the complicated seepage flow mechanism in horizontal gas well and the difficulty in the analysis of transient pressure test data, this paper establishes the mathematical models of well test analysis for horizontal gas well with different inner and outer boundary conditions. On the basis of obtaining the solutions of the mathematical models, several type curves are plotted with Stehfest inversion algorithm. For gas reservoir with closed outer boundary in vertical direction and infinite outer boundary in horizontal direction, while considering the effect of wellbore storage and skin effect, the pseudopressure behavior of the horizontal gas well can manifest four characteristic periods: pure wellbore storage period, early vertical radial flow period, early linear flow period, and late horizontal pseudoradial flow period. For gas reservoir with closed outer boundary both in vertical and horizontal directions, the pseudopressure behavior of the horizontal gas well adds the pseudosteady state flow period which appears after the boundary response. For gas reservoir with closed outer boundary in vertical direction and constant pressure outer boundary in horizontal direction, the pseudopressure behavior of the horizontal gas well adds the steady state flow period which appears after the boundary response. According to the characteristic lines which are manifested by pseudopressure derivative curve of each flow period, formulas are developed to obtain horizontal permeability, vertical permeability, skin factor, reservoir pressure, and pore volume of the gas reservoir, and thus the characteristic value method of well test analysis for horizontal gas well is established. Finally, the example study verifies that the new method is reliable. Characteristic value method of well test analysis for horizontal gas well makes the well test analysis

Numerical investigations on coupled heat transfer and synthetical performance of a pressurized volumetric receiver with MCRT–FVM method

International Nuclear Information System (INIS)

Cheng, Z.D.; He, Y.L.; Cui, F.Q.

2013-01-01

This paper presents an axisymmetric steady-state computational fluid dynamics model and further studies on the complex coupled heat transfer combined radiation–convection–conduction in the pressurized volumetric receiver (PVR), by combining the Finite Volume Method (FVM) and the Monte Carlo Ray-Trace (MCRT) method. Based on this, effects of geometric parameters of the compound parabolic concentrator (CPC) and properties of the porous absorber on synthetical characteristics and performance of the photo-thermal conversion process in the PVR are further analyzed and discussed detailedly. It is found that the solar flux density distributions are always very heterogeneous with large nonuniformities, and the variation trends of the corresponding temperature distributions are very similar to these but with much lower order of magnitude. The CPC shape determined by the CPC exit aperture has much larger effects on synthetical characteristics and performance of the PVR than that of the CPC entry aperture with a constant acceptance angle. And a suitable or optimal thickness of the porous absorber could be determined by examining where the drastic decreasing trends occur at the curves of variations of synthetical characteristics and performance with the porosity. - Highlights: ► An axisymmetric steady-state CFD model of PVR is presented with MCRT–FVM method. ► The complex coupled heat transfer and synthetical performance of the PVR are studied. ► The effects of geometric parameters and porous properties are analyzed and discussed. ► Solar flux and temperature in PVR are very heterogeneous with large nonuniformities. ► An optimal absorber thickness can be determined by examining the effects of porosity.

Intercomparison of performance characteristics of OSLDs and TLDs used for individual monitoring

International Nuclear Information System (INIS)

Meye, Phillipe Ondo

2016-07-01

This research work performed an intercomparison on some important performance characteristics of optically stimulated luminescence (OSL) and thermoluminescence (TL) dosimetry systems used by dosimetry services in Gabon and Ghana, respectively. The study verified the status of the selected performance indicators and propose ways to improve the performances of individual monitoring services of Ghana and Gabon if found necessary. The performance indicators assessed included the zero - dose, the minimum detectability and some important reader performance characteristics. These tests were performed using statistical and experimental methods. The overall uncertainty in measurement of the dosimetry systems of Ghana and Gabon for Hp(10) was determined using the IEC technical report TR 62461, and comparisons were carried out with IAEA 99, PTB 99, IEC 1066 and IEC1283 series performance standards. The IEC 62387 standard was used to assess the linearity dependence of the response and the coefficient of variation of the two dosimetry systems. For the Harshaw TLD 6600 system of the dosimetry service of Ghana, the Reference light QC test meets the requirement given in the user manual. For the OSL system microStar of the dosimetry system of Gabon, the three QC tests, DRK count, CAL count and LED count, meet the user manual requirements. However all these tests failed the statistical test that is part of counting statistics. This led to the conclusion that there may be some abnormalities in the counting system, and that the statistical abnormalities suspected have apparently no impact on the results of the reading. It was also concluded that since the DRK count and the CAL count failed the Chi - squared test by very small margin, a Gaussian distribution could still be considered as an approximation of the experimental data distributions of these two QC measurements. The zero dose for the Harshaw 6600 and the microStar system were found to be 0.026 mSv and 0.08 mSv respectively

The characteristics of ultra-high performance concrete and cracking behavior of reinforced concrete tensile specimens

Directory of Open Access Journals (Sweden)

H.A. Rahdar

2016-09-01

Full Text Available The tensile behavior of concrete depends on some factors such as member dimensions, reinforcement ratio, diameter of rebar, strength and elasticity modulus of material. In this research the experimental method is used to examine the characteristics and the behavior of ultra-high performance concrete on the tensile behavior of concrete members reinforced by steel rebar. The results show that increasing the rebar cover on diameter rebar ratio (C/d increases the initial stiffening before the cracking stage in concrete. Also, by increasing of reinforcement ratio the cracking space decreased.

The research on AP1000 nuclear main pumps’ complete characteristics and the normalization method

International Nuclear Information System (INIS)

Zhu, Rongsheng; Liu, Yong; Wang, Xiuli; Fu, Qiang; Yang, Ailing; Long, Yun

2017-01-01

Highlights: • Complete characteristics of main pump are researched into. • The quadratic character of head and torque under some operatings. • The characteristics tend to be the same under certain conditions. • The normalization method gives proper estimations on external characteristics. • The normalization method can efficiently improve the security computing. - Abstract: The paper summarizes the complete characteristics of nuclear main pumps based on experimental results and makes a detailed study, and then draws a series of important conclusions: with regard to the overall flow area, the runaway operating and 0-revolving-speed operating of nuclear main pumps both have quadratic characteristics; with regard to the infinite flow, the braking operation and the 0-revolving-speed operation show consistent external characteristics. To remedy the shortcomings of the traditional complete-characteristic expression with regards to only describing limited flow sections at specific revolving speeds, the paper proposes a normalization method. As an important boundary condition of the security computing of unstable transient process of the primary reactor coolant pump and the nuclear island primary circuit and secondary circuit, the precision of complete-characteristic data and curve impacts the precision of security computing. A normalization curve obtained by applying the normalization method to process complete-characteristic data could correctly, completely and precisely express the complete characteristics of the primary reactor coolant pump under any rotational speed and full flow, and is capable of giving proper estimations on external characteristics of the flow outside the test range and even of the infinite flow. These advantages are of great significance for the improvement of security computing of transient processes of the primary reactor coolant pump and the circuit system.

Frequency characteristic measurement of a fiber optic gyroscope using a correlation spectrum analysis method based on a pseudo-random sequence

International Nuclear Information System (INIS)

Li, Yang; Chen, Xingfan; Liu, Cheng

2015-01-01

The frequency characteristic is an important indicator of a system’s dynamic performance. The identification of a fiber optic gyroscope (FOG)’s frequency characteristic using a correlation spectrum analysis method based on a pseudo-random sequence is proposed. Taking the angle vibrator as the source of the test rotation stimulation and a pseudo-random sequence as the test signal, the frequency characteristic of a FOG is calculated according to the power spectral density of the rotation rate signal and the cross-power spectral density of the FOG’s output signal and rotation rate signal. A theoretical simulation is done to confirm the validity of this method. An experiment system is built and the test results indicate that the measurement error of the normalized amplitude–frequency response is less than 0.01, that the error of the phase–frequency response is less than 0.3 rad, and the overall measurement accuracy is superior to the traditional frequency-sweep method. By using this method, the FOG’s amplitude–frequency response and phase–frequency response can be measured simultaneously, quickly, accurately, and with a high frequency resolution. The described method meets the requirements of engineering applications. (paper)

Comparison of two different methods for evaluating the hydrodynamic performance of an industrial-scale fish-rearing unit

DEFF Research Database (Denmark)

Rasmussen, Michael R.; McLean, Ewen

2004-01-01

Laboratory-scale physical and mathematical models were evaluated for their utility in examining the hydrodynamic performance of a commercial fish-rearing tank. Each method was appraised with the common objective of predicting characteristic hydrodynamic behaviour of a full-scale tank. The two...

Postural Response Signal Characteristics Identified by Method of Developed Statokinesigram

Directory of Open Access Journals (Sweden)

Barbolyas Boris

2015-12-01

Full Text Available Human postural system is taken as complex biological system with specific input and output time characteristics, in this study. Evaluation of measured output characteristics is useful in medical diagnostics or in describing postural system disorders. System theory principle provide suitable basis for postural signals analysis. Participating volunteers were instructed to maintain quiet upright stance posture on firm support surface of stabilometric platform for 60s. Postural system actuation was realized by vibration stimuli applied bilaterally on Achilles tendons for 20s. Postural reaction signal, its time profile and static and dynamic characteristics were evaluated by Method of Developed Statokinesigram Trajectory (MDST.

Reliability of Lyapunov characteristic exponents computed by the two-particle method

Science.gov (United States)

Mei, Lijie; Huang, Li

2018-03-01

For highly complex problems, such as the post-Newtonian formulation of compact binaries, the two-particle method may be a better, or even the only, choice to compute the Lyapunov characteristic exponent (LCE). This method avoids the complex calculations of variational equations compared with the variational method. However, the two-particle method sometimes provides spurious estimates to LCEs. In this paper, we first analyze the equivalence in the definition of LCE between the variational and two-particle methods for Hamiltonian systems. Then, we develop a criterion to determine the reliability of LCEs computed by the two-particle method by considering the magnitude of the initial tangent (or separation) vector ξ0 (or δ0), renormalization time interval τ, machine precision ε, and global truncation error ɛT. The reliable Lyapunov characteristic indicators estimated by the two-particle method form a V-shaped region, which is restricted by d0, ε, and ɛT. Finally, the numerical experiments with the Hénon-Heiles system, the spinning compact binaries, and the post-Newtonian circular restricted three-body problem strongly support the theoretical results.

PERFORMANCE AND CHARACTERISTICS OF MUTUAL FUNDS: EVIDENCE FROM THE PORTUGUESE MARKET

Directory of Open Access Journals (Sweden)

Júlio Lobão

2015-12-01

Full Text Available In this paper we aim to study the relation between fund performance and fund attributes in the Portuguese market. The sample includes 124 equity funds, bond funds and money market funds that traded in the 2004-2011 period. A comprehensive set of fund-specific characteristics, never used before in conjunction in the literature, was considered. The methodology which was adopted had two distinct phases. Firstly, we compared the returns of each category of funds with the appropriate reference markets. Secondly, the fund performance, measured by the Jensen’s alpha, was used in a multi-factor model with panel data in which the independent variables were the fund attributes. The results show that Portuguese funds were, in general, not able to beat the benchmarks which is consistent with the existence of efficient financial markets. Only the fixed income mutual funds performed well. Moreover, it is possible to conclude that, for each category of mutual funds, their characteristics are useful to the investor in the moment of choosing the best funds. For example, in the case of funds that invest in Portuguese stocks, the best performance occurs among older and larger funds, funds with higher costs, funds with good past performance and funds whose trading activity is low.

A new method for the coefficients of the characteristic polynomial

International Nuclear Information System (INIS)

Gonzalez, H.E.

2006-01-01

In linear algebra, one can associate an equation to each square matrix: its characteristic equation or secular equation. Starting from this equation, the one characteristic polynomial that codes several important properties of the matrix is obtained: its own values, it determinant and it appearance. The first method to calculate those coefficients of this polynomial were proposed by the french astronomer Urbain Jean Joseph Le Verrier (1811-1877), from then on, many methods have intended to calculate these coefficients. In this work the author proposes a new one method and a bibliographical citation is given where the calculations with others methods that know each other for it, taking like reference the matrix used by Le Verrier are explained. It was concluded that it here proposed, besides being the only mexican method that is knew, has the advantage of being very easy of understanding and of calculating well, in the operations that it carries out, it doesn't use the division and it avoids fractions in matrices whose entrances are whole. This has a great importance for their use in the classroom for their great didactic value and in nuclear reactors and Genetic Engineering. (Author)

Transport theory calculation for a heterogeneous multi-assembly problem by characteristics method with direct neutron path linking technique

International Nuclear Information System (INIS)

Kosaka, Shinya; Saji, Etsuro

2000-01-01

A characteristics transport theory code, CHAPLET, has been developed for the purpose of making it practical to perform a whole LWR core calculation with the same level of calculational model and accuracy as that of an ordinary single assembly calculation. The characteristics routine employs the CACTUS algorithm for drawing ray tracing lines, which assists the two key features of the flux solution in the CHAPLET code. One is the direct neutron path linking (DNPL) technique which strictly connects angular fluxes at each assembly interface in the flux solution separated between assemblies. Another is to reduce the required memory storage by sharing the data related to ray tracing among assemblies with the same configuration. For faster computation, the coarse mesh rebalance (CMR) method and the Aitken method were incorporated in the code and the combined use of both methods showed the most promising acceleration performance among the trials. In addition, the parallelization of the flux solution was attempted, resulting in a significant reduction in the wall-clock time of the calculation. By all these efforts, coupled with the results of many verification studies, a whole LWR core heterogeneous transport theory calculation finally became practical. CHAPLET is thought to be a useful tool which can produce the reference solutions for analyses of an LWR (author)

Development of a particle method of characteristics (PMOC) for one-dimensional shock waves

Science.gov (United States)

Hwang, Y.-H.

2018-03-01

In the present study, a particle method of characteristics is put forward to simulate the evolution of one-dimensional shock waves in barotropic gaseous, closed-conduit, open-channel, and two-phase flows. All these flow phenomena can be described with the same set of governing equations. The proposed scheme is established based on the characteristic equations and formulated by assigning the computational particles to move along the characteristic curves. Both the right- and left-running characteristics are traced and represented by their associated computational particles. It inherits the computational merits from the conventional method of characteristics (MOC) and moving particle method, but without their individual deficiencies. In addition, special particles with dual states deduced to the enforcement of the Rankine-Hugoniot relation are deliberately imposed to emulate the shock structure. Numerical tests are carried out by solving some benchmark problems, and the computational results are compared with available analytical solutions. From the derivation procedure and obtained computational results, it is concluded that the proposed PMOC will be a useful tool to replicate one-dimensional shock waves.

A Performance Prediction Method for Pumps as Turbines (PAT Using a Computational Fluid Dynamics (CFD Modeling Approach

Directory of Open Access Journals (Sweden)

Emma Frosina

2017-01-01

Full Text Available Small and micro hydropower systems represent an attractive solution for generating electricity at low cost and with low environmental impact. The pump-as-turbine (PAT approach has promise in this application due to its low purchase and maintenance costs. In this paper, a new method to predict the inverse characteristic of industrial centrifugal pumps is presented. This method is based on results of simulations performed with commercial three-dimensional Computational Fluid Dynamics (CFD software. Model results have been first validated in pumping mode using data supplied by pump manufacturers. Then, the results have been compared to experimental data for a pump running in reverse. Experimentation has been performed on a dedicated test bench installed in the Department of Civil Construction and Environmental Engineering of the University of Naples Federico II. Three different pumps, with different specific speeds, have been analyzed. Using the model results, the inverse characteristic and the best efficiency point have been evaluated. Finally, results have been compared to prediction methods available in the literature.

A hybrid CFD/characteristics method for fast characterization of hypersonic blunt forebody/inlet flow

Science.gov (United States)

Gao, WenZhi; Li, ZhuFei; Yang, JiMing

2015-10-01

A hybrid CFD/characteristic method (CCM) was proposed for fast design and evaluation of hypersonic inlet flow with nose bluntness, which targets the combined advantages of CFD and method of characteristics. Both the accuracy and efficiency of the developed CCM were verified reliably, and it was well demonstrated for the external surfaces design of a hypersonic forebody/inlet with nose bluntness. With the help of CCM method, effects of nose bluntness on forebody shock shapes and the flowfield qualities which dominate inlet performance were examined and analyzed on the two-dimensional and axisymmetric configurations. The results showed that blunt effects of a wedge forebody are more substantial than that of related cone cases. For a conical forebody with a properly blunted nose, a recovery of the shock front back to that of corresponding sharp nose is exhibited, accompanied with a gradually fading out of entropy layer effects. Consequently a simplification is thought to be reasonable for an axisymmetric inlet with a proper compression angle, and a blunt nose of limited radius can be idealized as a sharp nose, as the spillage and flow variations at the entrance are negligible, even though the nose scale increases to 10% cowl lip radius. Whereas for two-dimensional inlets, the blunt effects are substantial since not only the inlet capturing/starting capabilities, but also the flow uniformities are obviously degraded.

Performance characteristics and parametric optimization of an irreversible magnetic Ericsson heat-pump

International Nuclear Information System (INIS)

Wei Fang; Lin Guoxing; Chen Jincan; Brueck, Ekkes

2011-01-01

Taking into account the finite-rate heat transfer in the heat-transfer processes, heat leak between the two external heat reservoirs, regenerative loss, regeneration time, and internal irreversibility due to dissipation of the cycle working substance, an irreversible magnetic Ericsson heat-pump cycle is presented. On the basis of the thermodynamic properties of magnetic materials, the performance characteristics of the irreversible magnetic Ericsson heat-pump are investigated and the relationship between the optimal heating load and the coefficient of performance (COP) is derived. Moreover, the maximum heating load and the corresponding COP as well as the maximum COP and the corresponding heating load are obtained. Furthermore, the other optimal performance characteristics are discussed in detail. The results obtained here may provide some new information for the optimal parameter design and the development of real magnetic Ericsson heat-pumps. -- Research Highlights: →The effects of multi-irreversibilities on the performance of a magnetic heat-pump are revealed. →Mathematical expressions of the heating load and the COP are derived and the optimal performance and operating parameters are analyzed and discussed. →Several important performance bounds are determined.

Investigation and Verification of the Aerodynamic Performance of a Fan/Booster with Through-flow Method

Science.gov (United States)

Liu, Xiaoheng; Jin, Donghai; Gui, Xingmin

2018-04-01

Through-flow method is still widely applied in the revolution of the design of a turbomachinery, which can provide not merely the performance characteristic but also the flow field. In this study, a program based on the through-flow method was proposed, which had been verified by many other numerical examples. So as to improve the accuracy of the calculation, abundant loss and deviation models dependent on the real geometry of engine were put into use, such as: viscous losses, overflow in gaps, leakage from a flow path through seals. By means of this program, the aerodynamic performance of a certain high through-flow commercial fan/booster was investigated. On account of the radial distributions of the relevant parameters, flow deterioration in this machine was speculated. To confirm this surmise, 3-D numerical simulation was carried out with the help of the NUMECA software. Through detailed analysis, the speculation above was demonstrated, which provide sufficient evidence for the conclusion that the through-flow method is an essential and effective method for the performance prediction of the fan/booster.

Effect of Lime Addition Methods on Performance Related Properties of Asphalt Concrete Mixture

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Amjad Hamd Khalil Albayati

2016-09-01

Full Text Available In the recent years, some of the newly constructed asphalt concrete pavements in Baghdad as well as other cities across Iraq showed premature failures with consequential negative impact on both roadway safety and economy. Frequently, load associated mode of failure (rutting and fatigue as well as, occasionally, moisture damage in some poorly drained sections are the main failure types found in those newly constructed road. In this research, hydrated lime was introduced into asphalt concrete mixtures of wearing course in two methods. The first one was the addition of dry lime on dry aggregate and the second one was the addition of dry lime on saturated surface dry aggregate moisturized by 2.0 to 3.0 percent of water. For each type of addition, five different percentages of lime as a partial replacement of ordinary limestone mineral filler were used; these were; 1.0, 1.5, 2.0, 2.5, and 3 percent by weight of aggregate besides a control mixture that did not contain lime. Marshall Mix design method was used and the performance properties of moisture damage, resilient modulus, permanent deformation and fatigue characteristics were evaluated using indirect tensile strength, uniaxial repeated loading and repeated flexural beam tests. Also, VESYS5W software was implemented to evaluate the pavements performance in terms of rut depth and fatigue area for a typical pavement structure. The main conclusion withdrawn from this research revealed that the use of 2.5 percent hydrated lime in dry addition method and wet addition method showed an improved fatigue and permanent deformation characteristics, lower moisture susceptibility and high resilient modulus.

Systematic Design Method and Experimental Validation of a 2-DOF Compliant Parallel Mechanism with Excellent Input and Output Decoupling Performances

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Yao Jiang

2017-06-01

Full Text Available The output and input coupling characteristics of the compliant parallel mechanism (CPM bring difficulty in the motion control and challenge its high performance and operational safety. This paper presents a systematic design method for a 2-degrees-of-freedom (DOFs CPM with excellent decoupling performance. A symmetric kinematic structure can guarantee a CPM with a complete output decoupling characteristic; input coupling is reduced by resorting to a flexure-based decoupler. This work discusses the stiffness design requirement of the decoupler and proposes a compound flexure hinge as its basic structure. Analytical methods have been derived to assess the mechanical performances of the CPM in terms of input and output stiffness, motion stroke, input coupling degree, and natural frequency. The CPM’s geometric parameters were optimized to minimize the input coupling while ensuring key performance indicators at the same time. The optimized CPM’s performances were then evaluated by using a finite element analysis. Finally, a prototype was constructed and experimental validations were carried out to test the performance of the CPM and verify the effectiveness of the design method. The design procedure proposed in this paper is systematic and can be extended to design the CPMs with other types of motion.

Standard guide for evaluating performance characteristics of phased-Array ultrasonic testing instruments and systems

CERN Document Server

American Society for Testing and Materials. Philadelphia

2008-01-01

1.1 This guide describes procedures for evaluating some performance characteristics of phased-array ultrasonic examination instruments and systems. 1.2 Evaluation of these characteristics is intended to be used for comparing instruments and systems or, by periodic repetition, for detecting long-term changes in the characteristics of a given instrument or system that may be indicative of impending failure, and which, if beyond certain limits, will require corrective maintenance. Instrument characteristics measured in accordance with this guide are expressed in terms that relate to their potential usefulness for ultrasonic examinations. Other electronic instrument characteristics in phased-array units are similar to non-phased-array units and may be measured as described in E 1065 or E 1324. 1.3 Ultrasonic examination systems using pulsed-wave trains and A-scan presentation (rf or video) may be evaluated. 1.4 This guide establishes no performance limits for examination systems; if such acceptance criteria ar...

Breeder design for enhanced performance and safety characteristics

International Nuclear Information System (INIS)

Fischer, G.J.; Atefi, B.; Yang, J.W.; Galperin, A.; Segev, M.

1980-01-01

A fast breeder reactor design has been created which offers a considerably extended fuel cycle and excellent performance characteristics. An example of a core designed to operate on a ten-year fuel cycle is described in some detail. Use of metal fuel along with a moderator such as beryllium oxide dispersed throughout the core provides both design flexibility and safety advantages such as a strong Doppler feedback and limited sodium void reactivity gain. Local power variations are small for the entire cycle; control requirements are also modest, and fuel cycle costs are low

Design characteristics of metallic fuel rod on its in-LMR performance

International Nuclear Information System (INIS)

Hwang, Woan; Kang Hee Young; Nam, Cheol; Kim, Jong Oh

1997-01-01

Fuel design is a key feature to assure LMR safety goals. To date, a large effort had been devoted to develop metallic fuels at ANL's experimental breeder reactor (EBR-II). The major design and performance parameters investigated include; thermal conductivity and temperature profile; smear density; axial plenum; FCMI and cladding deformation including creep, and fission gas release. In order to evaluate the sensitivity of each parameter, in-LMR performances of metallic fuels are not only reviewed by the experiment results in literatures, but also key design characteristics according to the variation of metallic fuel rod design parameters are analyzed by using the MACSIS code which simulates in-reactor behaviors of metal fuel rod. In this study, key design characteristics and the criteria which must be considered to design fuel rod in LMR, are proposed and discussed. (author). 14 refs., 4 figs

Effect of drying methods on the rheological characteristics and ...

African Journals Online (AJOL)

The effect of drying methods (sun and oven-drying) on the rheological properties and colour of amala, a thick paste from yam flour, was investigated using two varieties of yam (Dioscorea rotundata and. Dioscorea alata). The yam flour produced was later reconstituted to produce amala of different pasting characteristics, ...

PRODUCT OPTIMIZATION METHOD BASED ON ANALYSIS OF OPTIMAL VALUES OF THEIR CHARACTERISTICS

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Constantin D. STANESCU

2016-05-01

Full Text Available The paper presents an original method of optimizing products based on the analysis of optimal values of their characteristics . Optimization method comprises statistical model and analytical model . With this original method can easily and quickly obtain optimal product or material .

Kinanthropometric and performance characteristics of elite and non-elite female softball players.

Science.gov (United States)

Singh, S; Singh, M; Rathi, B

2013-12-01

The purpose of the present study was to compare the kinanthropometric and performance characteristics of elite and non-elite female softball players. A total forty elite and non-elite level female softball players were selected from the different colleges affiliated to the Guru Nanak Dev University, Amritsar, for the present study. The height of subjects was measured by using the standard anthropometric rod. Weight was measured with portable weighing machine. Widths and diameters of body parts were measured by using digital caliper. Girths and lengths were taken with steel tape. Skinfold thickness measurements were taken using the Slimguide skinfold caliper. All subjects were also assessed for performance tests i.e. vertical jump, 50m sprint, medicine ball throw, 10×4m shuttle run and reaction time. Independent samples t-test reveals that elite female softball players were significantly taller (Psoftball players also had significantly greater biacromial (Psoftball players. The non-elite female softball players were found to have significantly greater thigh circumference (Psoftball players. The non-elite players were also found to have significantly higher percentage body fat (Psoftball players. The elite female softball players had significantly greater kinanthropometric characteristics, body composition and performance characteristics than the non-elite female softball players.

Investigation of transfer characteristics of high performance graphene flakes.

Science.gov (United States)

Venugopal, Gunasekaran; Krishnamoorthy, Karthikeyan; Kim, Sang-Jae

2013-05-01

In this article, we attempted a study on field effect transport characteristics of graphene flakes. These graphene flakes were exfoliated by mechanical peeling-off technique and the electrical contacts were patterned by photo-lithographic method. Graphene devices have shown better transfer characteristics which was obtained even in low-voltage (graphene transistors were patterned on oxidized silicon wafers. A clear n-type to p-type transition at Dirac point and higher electron drain-current modulation in positive back-gate field with current minimum (the Dirac point) were observed at V(GS) = -1.7 V. The carrier mobility was determined from the measured transconductance. The transconductance of the graphene transistors was observed as high as 18.6 microS with a channel length of 68 microm. A maximum electron mobility of 1870 +/- 143 cm2/V x s and hole mobility of 1050 +/- 35 cm2/V x s were achieved at a drain bias 2.1 V which are comparatively higher values among reported for mechanically exfoliated graphene using lithographic method. The fabricated devices also sustained with high-current density for 40 hr in continuous operation without any change in device resistance, which could be applied for robust wiring applications.

A method of clustering observers with different visual characteristics

Energy Technology Data Exchange (ETDEWEB)

Niimi, Takanaga [Nagoya University School of Health Sciences, Department of Radiological Technology, 1-1-20 Daiko-minami, Higashi-ku, Nagoya 461-8673 (Japan); Imai, Kuniharu [Nagoya University School of Health Sciences, Department of Radiological Technology, 1-1-20 Daiko-minami, Higashi-ku, Nagoya 461-8673 (Japan); Ikeda, Mitsuru [Nagoya University School of Health Sciences, Department of Radiological Technology, 1-1-20 Daiko-minami, Higashi-ku, Nagoya 461-8673 (Japan); Maeda, Hisatoshi [Nagoya University School of Health Sciences, Department of Radiological Technology, 1-1-20 Daiko-minami, Higashi-ku, Nagoya 461-8673 (Japan)

2006-01-15

Evaluation of observer's image perception in medical images is important, and yet has not been performed because it is difficult to quantify visual characteristics. In the present study, we investigated the observer's image perception by clustering a group of 20 observers. Images of a contrast-detail (C-D) phantom, which had cylinders of 10 rows and 10 columns with different diameters and lengths, were acquired with an X-ray screen-film system with fixed exposure conditions. A group of 10 films were prepared for visual evaluations. Sixteen radiological technicians, three radiologists and one medical physicist participated in the observation test. All observers read the phantom radiographs on a transillumination image viewer with room lights off. The detectability was defined as the shortest length of the cylinders of which border the observers could recognize from the background, and was recorded using the number of columns. The detectability was calculated as the average of 10 readings for each observer, and plotted for different phantom diameter. The unweighted pair-group method using arithmetic averages (UPGMA) was adopted for clustering. The observers were clustered into two groups: one group selected objects with a demarcation from the vicinity, and the other group searched for the objects with their eyes constrained. This study showed a usefulness of the cluster method to select personnel with the similar perceptual predisposition when a C-D phantom was used in image quality control.

A method of clustering observers with different visual characteristics

International Nuclear Information System (INIS)

Niimi, Takanaga; Imai, Kuniharu; Ikeda, Mitsuru; Maeda, Hisatoshi

2006-01-01

Evaluation of observer's image perception in medical images is important, and yet has not been performed because it is difficult to quantify visual characteristics. In the present study, we investigated the observer's image perception by clustering a group of 20 observers. Images of a contrast-detail (C-D) phantom, which had cylinders of 10 rows and 10 columns with different diameters and lengths, were acquired with an X-ray screen-film system with fixed exposure conditions. A group of 10 films were prepared for visual evaluations. Sixteen radiological technicians, three radiologists and one medical physicist participated in the observation test. All observers read the phantom radiographs on a transillumination image viewer with room lights off. The detectability was defined as the shortest length of the cylinders of which border the observers could recognize from the background, and was recorded using the number of columns. The detectability was calculated as the average of 10 readings for each observer, and plotted for different phantom diameter. The unweighted pair-group method using arithmetic averages (UPGMA) was adopted for clustering. The observers were clustered into two groups: one group selected objects with a demarcation from the vicinity, and the other group searched for the objects with their eyes constrained. This study showed a usefulness of the cluster method to select personnel with the similar perceptual predisposition when a C-D phantom was used in image quality control

A numerical study on the flow and performance characteristics of a piezoelectric micropump with electromagnetic resistance for electrically conducting fluids

International Nuclear Information System (INIS)

An, Yong Jun; Choi, Chung Ryul; Kim, Chang Nyung

2008-01-01

A numerical analysis has been conducted for flow characteristics and performance of a micropump with piezodisk and MHD (MagnetoHydroDynamics) fluid. Various micro systems which could not be considered in the past have been recently growing with the development of MEMS (Micro Electro Mechanical System) and micro machining technology. Especially, micropumps, essential part of micro fluidic devices, are being lively studied by many researchers. In the present study, the piezo electric micropump with electromagnetic resistance for electrically conducting fluids is considered. The prescribed grid deformation method is used for the displacement of the membrane. The change of the performance of the micropump and flow characteristics of the electrically conducting fluid with the magnitude of the magnetic fields, duct size, the position of the inlet and outlet duct are investigated in the present study

Survey of engineering computational methods and experimental programs for estimating supersonic missile aerodynamic characteristics

Science.gov (United States)

Sawyer, W. C.; Allen, J. M.; Hernandez, G.; Dillenius, M. F. E.; Hemsch, M. J.

1982-01-01

This paper presents a survey of engineering computational methods and experimental programs used for estimating the aerodynamic characteristics of missile configurations. Emphasis is placed on those methods which are suitable for preliminary design of conventional and advanced concepts. An analysis of the technical approaches of the various methods is made in order to assess their suitability to estimate longitudinal and/or lateral-directional characteristics for different classes of missile configurations. Some comparisons between the predicted characteristics and experimental data are presented. These comparisons are made for a large variation in flow conditions and model attitude parameters. The paper also presents known experimental research programs developed for the specific purpose of validating analytical methods and extending the capability of data-base programs.

Study of the test method for prediction of air conditioning equipment seasonal performance

Energy Technology Data Exchange (ETDEWEB)

Thomas, S.B.

1980-05-01

The test procedure, Method of Testing, Rating and Estimating the Seasonal Performance of Central Air-Conditioners and Heat Pumps Operating in the Cooling Mode, has been analyzed. The analysis of the test procedure incorporated two main functions: (1) to determine the validity of the test procedure; and (2) to determine if there are other alternate methods of obtaining the same results with less testing burden. Data were collected from industry and analyzed for any significant trends. Certain conclusions are drawn about the energy efficiency ratios, degradation coefficients and seasonal energy efficiency ratios. An error analysis was performed on the test procedure to determine the approximate amount of error when using this procedure. A semi-empirical model assuming a first order system response was developed to determine the factors that affect the part-load and cooling-load factors. The corresponding transient characteristics are then determined in terms of a single time constant. A thermostat demand cycle is used to determine the relationship between on-time and cycle-time. Recommendations are made regarding an alternate method being used to determine the seasonal energy efficiency ratio.

Apparatus and method for determining characteristics of subsurface formations

International Nuclear Information System (INIS)

Coates, G.R.

1978-01-01

A method for the determination of a composite parameter of the formation water in formations surrounding a borehole using capture cross section data (or the conductivity) of the formation water is described and its use for the accurate determination of characteristics such as water saturation even in shaly regions, is demonstrated. (UK)

A massively parallel method of characteristic neutral particle transport code for GPUs

International Nuclear Information System (INIS)

Boyd, W. R.; Smith, K.; Forget, B.

2013-01-01

Over the past 20 years, parallel computing has enabled computers to grow ever larger and more powerful while scientific applications have advanced in sophistication and resolution. This trend is being challenged, however, as the power consumption for conventional parallel computing architectures has risen to unsustainable levels and memory limitations have come to dominate compute performance. Heterogeneous computing platforms, such as Graphics Processing Units (GPUs), are an increasingly popular paradigm for solving these issues. This paper explores the applicability of GPUs for deterministic neutron transport. A 2D method of characteristics (MOC) code - OpenMOC - has been developed with solvers for both shared memory multi-core platforms as well as GPUs. The multi-threading and memory locality methodologies for the GPU solver are presented. Performance results for the 2D C5G7 benchmark demonstrate 25-35 x speedup for MOC on the GPU. The lessons learned from this case study will provide the basis for further exploration of MOC on GPUs as well as design decisions for hardware vendors exploring technologies for the next generation of machines for scientific computing. (authors)

Seismic Performance of a Corroded Reinforce Concrete Frame Structure Using Pushover Method

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Meng Zhang

2018-01-01

Full Text Available SAP2000 software was used to build the finite element model of a six-storey-three-span reinforced concrete (RC frame structure. The numerical simulation of the seismic performance of the RC frame structure incorporating different levels of rebar corrosion was conducted using pushover analysis method. The degradation characteristics of the seismic performance of the corroded structure under severe earthquake were also analyzed. The results show that the seismic performance of the RC frame decreased significantly due to corrosion of the longitudinal rebars. And the interstory drift ratios increase dramatically with the increasing of the corrosion rate. At the same time, the formation and development of plastic hinges (beam hinges or column hinges will accelerate, which leads to a more aggravated deformation of the structure under rare earthquake action, resulting in a negative effect to the seismic bearing capacity of the structure.

Computer-aided detection of pulmonary nodules: influence of nodule characteristics on detection performance

International Nuclear Information System (INIS)

Marten, K.; Engelke, C.; Seyfarth, T.; Grillhoesl, A.; Obenauer, S.; Rummeny, E.J.

2005-01-01

AIM: To evaluate prospectively the influence of pulmonary nodule characteristics on detection performances of a computer-aided diagnosis (CAD) tool and experienced chest radiologists using multislice CT (MSCT). MATERIALS AND METHODS: MSCT scans of 20 consecutive patients were evaluated by a CAD system and two independent chest radiologists for presence of pulmonary nodules. Nodule size, position, margin, matrix characteristics, vascular and pleural attachments and reader confidence were recorded and data compared with an independent standard of reference. Statistical analysis for predictors influencing nodule detection or reader performance included chi-squared, retrograde stepwise conditional logistic regression with odds ratios and nodule detection proportion estimates (DPE), and ROC analysis. RESULTS: For 135 nodules, detection rates for CAD and readers were 76.3, 52.6 and 52.6%, respectively; false-positive rates were 0.55, 0.25 and 0.15 per examination, respectively. In consensus with CAD the reader detection rate increased to 93.3%, and the false-positive rate dropped to 0.1/scan. DPEs for nodules ≤5 mm were significantly higher for ICAD than for the readers (p<0.05). Absence of vascular attachment was the only significant predictor of nodule detection by CAD (p=0.0006-0.008). There were no predictors of nodule detection for reader consensus with CAD. In contrast, vascular attachment predicted nodule detection by the readers (p=0.0001-0.003). Reader sensitivity was higher for nodules with vascular attachment than for unattached nodules (sensitivities 0.768 and 0.369; 95% confidence intervals=0.651-0.861 and 0.253-0.498, respectively). CONCLUSION: CAD increases nodule detection rates, decreases false-positive rates and compensates for deficient reader performance in detection of smallest lesions and of nodules without vascular attachment

Physical Characteristics and Performance of Japanese Top-Level American Football Players.

Science.gov (United States)

Yamashita, Daichi; Asakura, Masaki; Ito, Yoshihiko; Yamada, Shinzo; Yamada, Yosuke

2017-09-01

Yamashita, D, Asakura, M, Ito, Y, Yamada, S, and Yamada, Y. Physical characteristics and performance of Japanese top-level American football players. J Strength Cond Res 31(9): 2455-2461, 2017-This study aimed to compare the physical characteristics and performance between top-level nonprofessional football players in Japan and National Football League (NFL) Combine invited players and between top-level and middle-level players in Japan to determine the factors that enhance performance in international and national competitions. A total of 168 American football players (>20 years) in Japan participated in an anthropometric (height and weight) and physical (vertical jump, long jump, 40-yard dash, pro-agility shuttle, 3-cone drill, and bench press repetition test) measurement program based on the NFL Combine program to compete in the selection of candidates for the Senior World Championship. All players were categorized into 1 of the 3 position groups based on playing position: skill players, big skill players, and linemen. Japanese players were additionally categorized into selected and nonselected players for the second tryout. The NFL Combine candidates had significantly better performance than selected Japanese players on all variables except on performance related to quickness among the 3 position groups. Compared with nonselected players, selected Japanese skill players had better performance in the 40-yard dash and bench press test and big skill players had better performance in the vertical jump, broad jump, and 40-yard dash. Selected and nonselected Japanese linemen were not different in any measurements. These results showed the challenges in American football in Japan, which include not only improving physical performance of top-level players, but also increasing the number of football players with good physical performance.

Free Vibration Characteristics of Cylindrical Shells Using a Wave Propagation Method

Directory of Open Access Journals (Sweden)

A. Ghoshal

2001-01-01

Full Text Available In the present paper, concept of a periodic structure is used to study the characteristics of the natural frequencies of a complete unstiffened cylindrical shell. A segment of the shell between two consecutive nodal points is chosen to be a periodic structural element. The present effort is to modify Mead and Bardell's approach to study the free vibration characteristics of unstiffened cylindrical shell. The Love-Timoshenko formulation for the strain energy is used in conjunction with Hamilton's principle to compute the natural propagation constants for two shell geometries and different circumferential nodal patterns employing Floquet's principle. The natural frequencies were obtained using Sengupta's method and were compared with those obtained from classical Arnold-Warburton's method. The results from the wave propagation method were found to compare identically with the classical methods, since both the methods lead to the exact solution of the same problem. Thus consideration of the shell segment between two consecutive nodal points as a periodic structure is validated. The variations of the phase constants at the lower bounding frequency for the first propagation band for different nodal patterns have been computed. The method is highly computationally efficient.

Anatomic and histological characteristics of vagina reconstructed by McIndoe method

Directory of Open Access Journals (Sweden)

Kozarski Jefta

2009-01-01

Full Text Available Background/Aim. Congenital absence of vagina is known from ancient times of Greek. According to the literature data, incidence is 1/4 000 to 1/20 000. Treatment of this anomaly includes non-operative and operative procedures. McIndoe procedure uses split skin graft by Thiersch. The aim of this study was to establish anatomic and histological characteristics of vagina reconstructed by McIndoe method in Mayer Küster-Rockitansky Hauser (MKRH syndrome and compare them with normal vagina. Methods. The study included 21 patients of 18 and more years with congenital anomaly known as aplasio vaginae within the Mayer Küster-Rockitansky Hauser syndrome. The patients were operated on by the plastic surgeon using the McIndoe method. The study was a retrospective review of the data from the history of the disease, objective and gynecological examination and cytological analysis of native preparations of vaginal stain (Papanicolau. Comparatively, 21 females of 18 and more years with normal vaginas were also studied. All the subjects were divided into the groups R (reconstructed and C (control and the subgroups according to age up to 30 years (1 R, 1C, from 30 to 50 (2R, 2C, and over 50 (3R, 3C. Statistical data processing was performed by using the Student's t-test and Mann-Writney U-test. A value of p < 0.05 was considered statistically significant. Results. The results show that there are differences in the depth and the wideness of reconstructed vagina, but the obtained values are still in the range of normal ones. Cytological differences between a reconstructed and the normal vagina were found. Conclusion. A reconstructed vagina is smaller than the normal one regarding depth and width, but within the range of normal values. A split skin graft used in the reconstruction, keeps its own cytological, i.e. histological and, so, biological characteristics.

The analogy method for the description of external characteristic of inner combustion engines

Directory of Open Access Journals (Sweden)

A. Stonys

2004-10-01

Full Text Available The original data for the evaluation of vehicle motion dynamics is external characteristic of its engine, which consists of three parameters: torque, power and specific fuel consumption. It is very important to have the dependences of these characteristics on revs for various engine load cases, creating a vehicle model under real motion conditions. Load cases are defined by a load coefficient. Car-makers usually don’t declare full engine external characteristics, which overtake all load coefficient variation interval. The purpose of this article is to research, how to get full description of engine torque function without its full data. The analogy method, which is used in polymers and composites mechanics, was employed for the description of a torque function. The method is based on the creation of summarized characteristic, making horizontal and vertical shifts of torque dependences. From the curve it is possible to get a proper characteristic at a chosen load coefficient.

A time-dependent neutron transport method of characteristics formulation with time derivative propagation

Energy Technology Data Exchange (ETDEWEB)

Hoffman, Adam J., E-mail: adamhoff@umich.edu; Lee, John C., E-mail: jcl@umich.edu

2016-02-15

A new time-dependent Method of Characteristics (MOC) formulation for nuclear reactor kinetics was developed utilizing angular flux time-derivative propagation. This method avoids the requirement of storing the angular flux at previous points in time to represent a discretized time derivative; instead, an equation for the angular flux time derivative along 1D spatial characteristics is derived and solved concurrently with the 1D transport characteristic equation. This approach allows the angular flux time derivative to be recast principally in terms of the neutron source time derivatives, which are approximated to high-order accuracy using the backward differentiation formula (BDF). This approach, called Source Derivative Propagation (SDP), drastically reduces the memory requirements of time-dependent MOC relative to methods that require storing the angular flux. An SDP method was developed for 2D and 3D applications and implemented in the computer code DeCART in 2D. DeCART was used to model two reactor transient benchmarks: a modified TWIGL problem and a C5G7 transient. The SDP method accurately and efficiently replicated the solution of the conventional time-dependent MOC method using two orders of magnitude less memory.

A time-dependent neutron transport method of characteristics formulation with time derivative propagation

International Nuclear Information System (INIS)

Hoffman, Adam J.; Lee, John C.

2016-01-01

A new time-dependent Method of Characteristics (MOC) formulation for nuclear reactor kinetics was developed utilizing angular flux time-derivative propagation. This method avoids the requirement of storing the angular flux at previous points in time to represent a discretized time derivative; instead, an equation for the angular flux time derivative along 1D spatial characteristics is derived and solved concurrently with the 1D transport characteristic equation. This approach allows the angular flux time derivative to be recast principally in terms of the neutron source time derivatives, which are approximated to high-order accuracy using the backward differentiation formula (BDF). This approach, called Source Derivative Propagation (SDP), drastically reduces the memory requirements of time-dependent MOC relative to methods that require storing the angular flux. An SDP method was developed for 2D and 3D applications and implemented in the computer code DeCART in 2D. DeCART was used to model two reactor transient benchmarks: a modified TWIGL problem and a C5G7 transient. The SDP method accurately and efficiently replicated the solution of the conventional time-dependent MOC method using two orders of magnitude less memory.

Characteristics of ovulation method acceptors: a cross-cultural assessment.

Science.gov (United States)

Klaus, H; Labbok, M; Barker, D

1988-01-01

Five programs of instruction in the ovulation method (OM) in diverse geographic and cultural settings are described, and characteristics of approximately 200 consecutive OM acceptors in each program are examined. Major findings include: the religious background and family size of acceptors are variable, as is the level of previous contraceptive use. Acceptors are drawn from a wide range of socioeconomic and religious backgrounds; however, family planning intention was similarly distributed in all five countries. In sum, the ovulation method is accepted by persons from a variety of backgrounds within and between cultural setting.

Workplace-related generational characteristics of nurses: A mixed-method systematic review.

Science.gov (United States)

Stevanin, Simone; Palese, Alvisa; Bressan, Valentina; Vehviläinen-Julkunen, Katri; Kvist, Tarja

2018-06-01

The aim of this study was to describe and summarize workplace characteristics of three nursing generations: Baby Boomers, Generations X and Y. Generational differences affect occupational well-being, nurses' performance, patient outcomes and safety; therefore, nurse managers, administrators and educators are interested increasingly in making evidence-based decisions about the multigenerational nursing workforce. Mixed-method systematic review. Medline, CINAHL, PsycINFO and Scopus (January 1991-January 2017). (1) The Joanna Briggs Institute's method for conducting mixed-method systematic reviews; (2) the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and (3) the Enhancing Transparency in Reporting the Synthesis of Qualitative Research guidelines. The studies' methodological quality was assessed with the Mixed-Methods Appraisal Tool. Quantitative and mixed-method studies were transformed into qualitative methods using a convergent qualitative synthesis and qualitative findings were combined with a narrative synthesis. Thirty-three studies were included with three main themes and 11 subthemes: (1) Job attitudes (work engagement; turnover intentions, reasons for leaving; reasons, incentives/disincentives to continue nursing); (2) Emotion-related job aspects (stress/resilience; well-being/job satisfaction; affective commitment; unit climate; work ethic) and (3) Practice and leadership-related aspects (autonomy; perceived competence; leadership relationships and perceptions). Baby Boomers reported lower levels of stress and burnout than did Generations X and Y, different work engagement, factors affecting workplace well-being and retention and greater intention to leave compared with Generation Y, which was less resilient, but more cohesive. Although several studies reported methodological limitations and conflicting findings, generational differences in nurses' job attitudes, emotional, practice and leadership factors should be considered to enhance

Algebraic collapsing acceleration of the characteristics method with anisotropic scattering

International Nuclear Information System (INIS)

Le Tellier, R.; Hebert, A.; Roy, R.

2004-01-01

In this paper, the characteristics solvers implemented in the lattice code Dragon are extended to allow a complete anisotropic treatment of the collision operator. An efficient synthetic acceleration method, called Algebraic Collapsing Acceleration (ACA), is presented. Tests show that this method can substantially speed up the convergence of scattering source iterations. The effect of boundary conditions, either specular or white reflections, on anisotropic scattering lattice-cell problems is also considered. (author)

A Rapid Aeroelasticity Optimization Method Based on the Stiffness characteristics

OpenAIRE

Yuan, Zhe; Huo, Shihui; Ren, Jianting

2018-01-01

A rapid aeroelasticity optimization method based on the stiffness characteristics was proposed in the present study. Large time expense in static aeroelasticity analysis based on traditional time domain aeroelasticity method is solved. Elastic axis location and torsional stiffness are discussed firstly. Both torsional stiffness and the distance between stiffness center and aerodynamic center have a direct impact on divergent velocity. The divergent velocity can be adjusted by changing the cor...

A method for optimizing the performance of buildings

DEFF Research Database (Denmark)

Pedersen, Frank

2007-01-01

needed for solving the optimization problem. Furthermore, the algorithm uses so-called domain constraint functions in order to ensure that the input to the simulation software is feasible. Using this technique avoids performing time-consuming simulations for unrealistic design decisions. The algorithm......This thesis describes a method for optimizing the performance of buildings. Design decisions made in early stages of the building design process have a significant impact on the performance of buildings, for instance, the performance with respect to the energy consumption, economical aspects......, and the indoor environment. The method is intended for supporting design decisions for buildings, by combining methods for calculating the performance of buildings with numerical optimization methods. The method is able to find optimum values of decision variables representing different features of the building...

Performance ratio hardness characteristics polystyrene-metal composite materials

International Nuclear Information System (INIS)

Klepikov, V.F.; Prokhorenko, E.M.; Lytvynenko, V.V.; Zakharchenko, A.A.; Hazhmuradov, M.A.

2015-01-01

The methods of measuring the hardness of layered polystyrene-metallic composite materials. It is proposed to use powder-like tungsten and powder-like steel as radiation-protective layer. A measurement of the hardness of composites of different composition, and given its dependence on the particle size and their form. The possibility of increasing the hardness of the composites reinforced with metallic additives. Radiation-protective characteristics were calculated for the studied species of composite materials. Influence of the quantitative composition of the metal components is studied on the change of the absorbed dose of gamma radiation

A Modelling Method of Bolt Joints Based on Basic Characteristic Parameters of Joint Surfaces

Science.gov (United States)

Yuansheng, Li; Guangpeng, Zhang; Zhen, Zhang; Ping, Wang

2018-02-01

Bolt joints are common in machine tools and have a direct impact on the overall performance of the tools. Therefore, the understanding of bolt joint characteristics is essential for improving machine design and assembly. Firstly, According to the experimental data obtained from the experiment, the stiffness curve formula was fitted. Secondly, a finite element model of unit bolt joints such as bolt flange joints, bolt head joints, and thread joints was constructed, and lastly the stiffness parameters of joint surfaces were implemented in the model by the secondary development of ABAQUS. The finite element model of the bolt joint established by this method can simulate the contact state very well.

A method to stabilize the temperature dependent performance of G-APD arrays

Energy Technology Data Exchange (ETDEWEB)

Huh, Yoonsuk [Molecular Imaging Research and Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Sungkyunkwan University, School of Medicine, Seoul (Korea, Republic of); Choi, Yong; Ho Jung, Jin; Jung, Jiwoong [Molecular Imaging Research and Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of)

2015-02-01

This paper presents a compensation method to stabilize the temperature dependent performance of Geiger-mode Avalanche Photodiode (G-APD) arrays for Positron Emission Tomography (PET). The compensation method is used to identify the bias voltage range that provides stable performance even at different temperatures using the G-APD’s characteristics, and to control the photo-peak variation as a function of temperature using the preamplifier gain within the identified bias voltage range. A pair of G-APD detectors and temperature sensors were located in the temperature chamber and the preamplifiers which can control the gain of the detectors using the digital potentiometer were positioned outside the chamber. The performance of the G-APD detector, especially energy resolution and coincidence timing resolution, was characterized as a function of bias voltage at different temperatures from 20 °C to 40 °C at 5 °C increments; the energy resolution, coincidence timing resolution, and photo-peak position of all channels of G-APD PET detectors before and after the preamplifier gain correction were then measured and compared. The results of this study demonstrated that the optimal bias voltage range providing the good energy and coincidence timing resolution, 12.1±1.2% and 1.30±0.09 ns, respectively, could be identified at the temperature range and the photo-peak variation and the performance at different temperatures could be stabilized by adjusting the preamplifier gain within the identified bias voltage range. We concluded the proposed method to be reliable and useful for the development of the PET system using G-APD arrays.

Enhanced affordable methods for assessment of material characteristics and consolidation effects on stone and mortar

Science.gov (United States)

Drdacky, M.; Slizkova, Z.

2012-04-01

In situ considerate testing of surface cohesion of historic stone and mortar materials suffers from a lack of suitable affordable non-destructive methods. The problem is mainly important for assessment of surface degradation characteristics and/or evaluation of effectiveness of consolidation treatment of degraded historic materials. The paper presents two innovations of simple testing methods which provide reliable data on material cohesion and water uptake. The so called "Scotch Tape Test" or peeling test has been introduced into the field of conservation for testing the cohesion qualities of historic materials mainly stone and renders in sixties without any standards or reliably verified recommendations for the above mentioned application in the conservation practice. Licentious use without adequate knowledge and sufficient understanding leads to non-comparable and non-reproducible as well as in many cases incorrect and severely biased results and assessments. Therefore, the authors after a research and comparative testing have established limits for its application, reliable procedures and a "standard" protocol for testing of cohesion characteristics of brittle and quasi brittle materials mainly mortars and stones. This article presents a detailed analysis of the peeling test procedures, and suggests recommendations for performing peeling tests and for evaluating the obtained results. Also in situ testing of material water uptake is a very basic and indispensable technique in conservation practice and it correlates significantly with some other material characteristics. The capillary properties of porous materials can be measured in situ using a Karsten tube and modified tools or methods which are quite cumbersome, and cannot be performed on inclined surfaces, e.g. vaults or ceilings. There are other difficulties with Karsten tube measurements, e.g. problems with fixing a heavy glass tube on vertical surfaces, a need for two operators, and soiling of the surface

Methods for calculating the speed-up characteristics of steam-water turbines

International Nuclear Information System (INIS)

Golovach, E.A.

1981-01-01

The methods of approximate and specified calculations of speed- up characteristics of steam-water turbines are considered. The specified non-linear method takes into account change of thermal efficiency, heat drop and losses in the turbine as well as vacuum break-up the condenser. Speed-up characteristics of the K-1000-60-1500 turbine are presented. The calculational results obtained by the non-linear method are compared with the calculations conducted by the approximate linearized method. Differences in the frequency speed up of the turbine rotor rotation calculated by the two methods constitute only 0.5-2.0%. That is why it is necessary to take into account in the specified calculations first of all the most important factors following the rotor speed- up in the following consequence: valve shift of the high pressure cylinder (HPC); steam volume in front of the HPC; shift of the valves behind the separator-steam superheater (SSS); steam volumes and moisture boiling in the SSS; steam consumption for regenerating heating of feed water, steam volumes at the intermediate elements of the turbine, losses in the turbine, heat drop and thermal efficiency [ru

Performance characteristics of the DIII-D advanced divertor cryopump

International Nuclear Information System (INIS)

Menon, M.M.; Maingi, R.; Wade, M.R.; Baxi, C.B.; Campbell, G.L.; Holtrop, K.L.; Hyatt, A.W.; Laughon, G.J.; Makariou, C.C.; Mahdavi, M.A.; Reis, E.E.; Schaffer, M.J.; Schaubel, K.M.; Scoville, J.T.; Smith, J.P.; Stambaugh, R.D.

1993-10-01

A cryocondensation pump, cooled by forced flow of two-phase helium, has been installed for particle exhaust from the divertor region of the DIII-D tokamak. The Inconel pumping surface is of coaxial geometry, 25.4 mm in outer diameter and 11.65 m in length. Because of the tokamak environment, the pump is designed to perform under relatively high pulsed heat loads (300 Wm -2 ). Results of measurements made on the pumping characteristics for D 2 , H 2 , and Ar are discussed

Preventive Care Quality of Medicare Accountable Care Organizations: Associations of Organizational Characteristics With Performance.

Science.gov (United States)

Albright, Benjamin B; Lewis, Valerie A; Ross, Joseph S; Colla, Carrie H

2016-03-01

Accountable Care Organizations (ACOs) are a delivery and payment model aiming to coordinate care, control costs, and improve quality. Medicare ACOs are responsible for 8 measures of preventive care quality. To create composite measures of preventive care quality and examine associations of ACO characteristics with performance. This is a cross-sectional study of Medicare Shared Savings Program and Pioneer participants. We linked quality performance to descriptive data from the National Survey of ACOs. We created composite measures using exploratory factor analysis, and used regression to assess associations with organizational characteristics. Of 252 eligible ACOs, 246 reported on preventive care quality, 177 of which completed the survey (response rate=72%). In their first year, ACOs lagged behind PPO performance on the majority of comparable measures. We identified 2 underlying factors among 8 measures and created composites for each: disease prevention, driven by vaccines and cancer screenings, and wellness screening, driven by annual health screenings. Participation in the Advanced Payment Model, having fewer specialists, and having more Medicare ACO beneficiaries per primary care provider were associated with significantly better performance on both composites. Better performance on disease prevention was also associated with inclusion of a hospital, greater electronic health record capabilities, a larger primary care workforce, and fewer minority beneficiaries. ACO preventive care quality performance is related to provider composition and benefitted by upfront investment. Vaccine and cancer screening quality performance is more dependent on organizational structure and characteristics than performance on annual wellness screenings, likely due to greater complexity in eligibility determination and service administration.

Performance Analysis of a Maximum Power Point Tracking Technique using Silver Mean Method

Directory of Open Access Journals (Sweden)

Shobha Rani Depuru

2018-01-01

Full Text Available The proposed paper presents a simple and particularly efficacious Maximum Power Point Tracking (MPPT algorithm based on Silver Mean Method (SMM. This method operates by choosing a search interval from the P-V characteristics of the given solar array and converges to MPP of the Solar Photo-Voltaic (SPV system by shrinking its interval. After achieving the maximum power, the algorithm stops shrinking and maintains constant voltage until the next interval is decided. The tracking capability efficiency and performance analysis of the proposed algorithm are validated by the simulation and experimental results with a 100W solar panel for variable temperature and irradiance conditions. The results obtained confirm that even without any perturbation and observation process, the proposed method still outperforms the traditional perturb and observe (P&O method by demonstrating far better steady state output, more accuracy and higher efficiency.

Numerical investigation of the variable nozzle effect on the mixed flow turbine performance characteristics

Science.gov (United States)

Meziri, B.; Hamel, M.; Hireche, O.; Hamidou, K.

2016-09-01

There are various matching ways between turbocharger and engine, the variable nozzle turbine is the most significant method. The turbine design must be economic with high efficiency and large capacity over a wide range of operational conditions. These design intents are used in order to decrease thermal load and improve thermal efficiency of the engine. This paper presents an original design method of a variable nozzle vane for mixed flow turbines developed from previous experimental and numerical studies. The new device is evaluated with a numerical simulation over a wide range of rotational speeds, pressure ratios, and different vane angles. The compressible turbulent steady flow is solved using the ANSYS CFX software. The numerical results agree well with experimental data in the nozzleless configuration. In the variable nozzle case, the results show that the turbine performance characteristics are well accepted in different open positions and improved significantly in low speed regime and at low pressure ratio.

The Relationship Among Teaching Methods, Student Characteristics, and Student Involvement in Learning

Science.gov (United States)

Anderson, Lorin W.; Soctt, Corinne C.

1978-01-01

Individual students tend to benefit differently from different teaching methods; however, when little or nothing is known of the entering students' characteristics regarding learning involvement, the high school teacher would be wise to use the classroom discourse method of teaching. (JD)

Study on performance and emission characteristics of a single cylinder diesel engine using exhaust gas recirculation

Directory of Open Access Journals (Sweden)

Anantha Raman Lakshmipathi

2017-01-01

Full Text Available Exhaust gas re-circulation is a method used in compression ignition engines to control and reduce NOx emission. These emissions are controlled by reducing the oxygen concentration inside the cylinder and thereby reducing the flame temperature of the charge mixture inside the combustion chamber. In the present investigation, experiments were performed to study the effect of exhaust gas re-circulation on performance and emission characteristics in a four stroke single cylinder, water cooled and constant speed diesel engine. The experiments were performed to study the performance and emissions for different exhaust gas re-circulation ratios of the engine. Performance parameters such as brake thermal efficiency, indicated thermal efficiency, specific fuel consumption, total fuel consumption and emission parameters such as oxides of nitrogen, unburned hydrocarbons, carbon monoxide, carbon dioxide and smoke opacity were measured. Reductions in NOx and CO2 were observed but other emissions like HC, CO, and smoke opacity were found to have increased with the usage of exhaust gas re-circulation. The 15% exhaust gas re-circulation was found optimum for the engine in the aspects of performance and emission.

Talent in Female Gymnastics: a Survival Analysis Based upon Performance Characteristics.

Science.gov (United States)

Pion, J; Lenoir, M; Vandorpe, B; Segers, V

2015-11-01

This study investigated the link between the anthropometric, physical and motor characteristics assessed during talent identification and dropout in young female gymnasts. 3 cohorts of female gymnasts (n=243; 6-9 years) completed a test battery for talent identification. Performance-levels were monitored over 5 years of competition. Kaplan-Meier and Cox Proportional Hazards analyses were conducted to determine the survival rate and the characteristics that influence dropout respectively. Kaplan-Meier analysis indicated that only 18% of the female gymnasts that passed the baseline talent identification test survived at the highest competition level 5 years later. The Cox Proportional Hazards Model indicated that gymnasts with a score in the best quartile for a specific characteristic significantly increased chances of survival by 45-129%. These characteristics being: basic motor skills (129%), shoulder strength (96%), leg strength (53%) and 3 gross motor coordination items (45-73%). These results suggest that tests batteries commonly used for talent identification in young female gymnasts may also provide valuable insights into future dropout. Therefore, multidimensional test batteries deserve a prominent place in the selection process. The individual test results should encourage trainers to invest in an early development of basic physical and motor characteristics to prevent attrition. © Georg Thieme Verlag KG Stuttgart · New York.

Study on Fault Diagnostics of a Turboprop Engine Using Inverse Performance Model and Artificial Intelligent Methods

Science.gov (United States)

Kong, Changduk; Lim, Semyeong

2011-12-01

Recently, the health monitoring system of major gas path components of gas turbine uses mostly the model based method like the Gas Path Analysis (GPA). This method is to find quantity changes of component performance characteristic parameters such as isentropic efficiency and mass flow parameter by comparing between measured engine performance parameters such as temperatures, pressures, rotational speeds, fuel consumption, etc. and clean engine performance parameters without any engine faults which are calculated by the base engine performance model. Currently, the expert engine diagnostic systems using the artificial intelligent methods such as Neural Networks (NNs), Fuzzy Logic and Genetic Algorithms (GAs) have been studied to improve the model based method. Among them the NNs are mostly used to the engine fault diagnostic system due to its good learning performance, but it has a drawback due to low accuracy and long learning time to build learning data base if there are large amount of learning data. In addition, it has a very complex structure for finding effectively single type faults or multiple type faults of gas path components. This work builds inversely a base performance model of a turboprop engine to be used for a high altitude operation UAV using measured performance data, and proposes a fault diagnostic system using the base engine performance model and the artificial intelligent methods such as Fuzzy logic and Neural Network. The proposed diagnostic system isolates firstly the faulted components using Fuzzy Logic, then quantifies faults of the identified components using the NN leaned by fault learning data base, which are obtained from the developed base performance model. In leaning the NN, the Feed Forward Back Propagation (FFBP) method is used. Finally, it is verified through several test examples that the component faults implanted arbitrarily in the engine are well isolated and quantified by the proposed diagnostic system.

Personality Characteristics and Level of Performance of Male County Extension Agents in Wisconsin.

Science.gov (United States)

Pandya, Dasharathrai Navnitrai

The major purpose of this study was to determine the relationship between selected personality characteristics and attitudes of male extension agents in Wisconsin, and their level of job performance. The relationships between selected background factors and the level of agent's job performance were also studied. Subjects were 79 male county agents…

Work-group characteristics and performance in collectivistic and individualistic cultures.

Science.gov (United States)

Sosik, John J; Jung, Dong I

2002-02-01

The authors conducted a cross-cultural longitudinal investigation of the effects of culture (individualism-collectivism dichotomy) on group characteristics (functional heterogeneity, preference for teamwork, group potency, outcome expectation) and on performance of 83 work groups performing 2 decision-making tasks over a 15-week period. The individualists (U.S. students) reported higher levels of functional heterogeneity and group potency and attained higher levels of group performance than did the collectivists (Korean students). In addition, culture and time interacted to influence ratings of group potency and outcome expectation. The difference in ratings of group potency between individualists and collectivists increased over time. Outcome expectation was greater among the collectivists in Time 1 and among the individualists in Time 2. The authors discuss implications for future cross-cultural group research and international management.

Performance characteristics of digital vs film screen mammography in community practice.

Science.gov (United States)

Dabbous, Firas; Dolecek, Therese A; Friedewald, Sarah M; Tossas-Milligan, Katherine Y; Macarol, Tere; Summerfelt, Wm Thomas; Rauscher, Garth H

2018-05-01

We compared the performance characteristics of 297 629 full field digital (FFDM) and 416 791 screen film mammograms (SFM). Sensitivity increased with age, decreased with breast density, and was lower for more aggressive and lobular tumors. While sensitivity did not differ significantly by modality, specificity was generally 1%-2% points higher for FFDM than for SFM across age and breast density categories. The lower recall rate for FFDM vs SFM in our study may partially explain performance differences by modality. In this large health care organization, modest gains in performance were achieved with the introduction of FFDM as a replacement for SFM. © 2017 Wiley Periodicals, Inc.

How do task characteristics affect learning and performance? The roles of variably mapped and dynamic tasks.

Science.gov (United States)

Macnamara, Brooke N; Frank, David J

2018-05-01

For well over a century, scientists have investigated individual differences in performance. The majority of studies have focused on either differences in practice, or differences in cognitive resources. However, the predictive ability of either practice or cognitive resources varies considerably across tasks. We are the first to examine task characteristics' impact on learning and performance in a complex task while controlling for other task characteristics. In 2 experiments we test key theoretical task characteristic thought to moderate the relationship between practice, cognitive resources, and performance. We devised a task where each of several key task characteristics can be manipulated independently. Participants played 5 rounds of a game similar to the popular tower defense videogame Plants vs. Zombies where both cognitive load and game characteristics were manipulated. In Experiment 1, participants either played a consistently mapped version-the stimuli and the associated meaning of their properties were constant across the 5 rounds-or played a variably mapped version-the stimuli and the associated meaning of their properties changed every few minutes. In Experiment 2, participants either played a static version-that is, turn taking with no time pressure-or played a dynamic version-that is, the stimuli moved regardless of participants' response rates. In Experiment 1, participants' accuracy and efficiency were substantially hindered in the variably mapped conditions. In Experiment 2, learning and performance accuracy were hindered in the dynamic conditions, especially when under cognitive load. Our results suggest that task characteristics impact the relative importance of cognitive resources and practice on predicting learning and performance. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

GeneNetWeaver: in silico benchmark generation and performance profiling of network inference methods.

Science.gov (United States)

Schaffter, Thomas; Marbach, Daniel; Floreano, Dario

2011-08-15

Over the last decade, numerous methods have been developed for inference of regulatory networks from gene expression data. However, accurate and systematic evaluation of these methods is hampered by the difficulty of constructing adequate benchmarks and the lack of tools for a differentiated analysis of network predictions on such benchmarks. Here, we describe a novel and comprehensive method for in silico benchmark generation and performance profiling of network inference methods available to the community as an open-source software called GeneNetWeaver (GNW). In addition to the generation of detailed dynamical models of gene regulatory networks to be used as benchmarks, GNW provides a network motif analysis that reveals systematic prediction errors, thereby indicating potential ways of improving inference methods. The accuracy of network inference methods is evaluated using standard metrics such as precision-recall and receiver operating characteristic curves. We show how GNW can be used to assess the performance and identify the strengths and weaknesses of six inference methods. Furthermore, we used GNW to provide the international Dialogue for Reverse Engineering Assessments and Methods (DREAM) competition with three network inference challenges (DREAM3, DREAM4 and DREAM5). GNW is available at http://gnw.sourceforge.net along with its Java source code, user manual and supporting data. Supplementary data are available at Bioinformatics online. dario.floreano@epfl.ch.

Electromagnetic characteristics and static torque of a solid salient poles synchronous motor computed by 3D-finite element method magnetics

International Nuclear Information System (INIS)

Popnikolova Radevska, Mirka; Cundev, Milan; Petkovska, Lidija

2002-01-01

In these paper is presented a methodology for numerical determination and complex analysis of the electromagnetic characteristics of the Solid Salient Poles Synchronous Motor, with rated data: 2.5 kW, 240 V and 1500 r.p.m.. A mathematical model and original algorithm for the nonlinear and iterative calculations by using Finite Element Method in 3D domain will be given. The program package FEM-3D will be used to perform automatically mesh generation of the finite elements in the 3D domain, calculation of the magnetic field distribution, as well as electromagnetic characteristics and Static torque in SSPSM. (Author)

Comparisons and Analyses of Gifted Students' Characteristics and Learning Methods

Science.gov (United States)

Lu, Jiamei; Li, Daqi; Stevens, Carla; Ye, Renmin

2017-01-01

Using PISA 2009, an international education database, this study compares gifted and talented (GT) students in three groups with normal (non-GT) students by examining student characteristics, reading, schooling, learning methods, and use of strategies for understanding and memorizing. Results indicate that the GT and non-GT gender distributions…

Fundamental characteristics and simplified evaluation method of dynamic earth pressure

International Nuclear Information System (INIS)

Nukui, Y.; Inagaki, Y.; Ohmiya, Y.

1989-01-01

In Japan, a method is commonly used in the evaluation of dynamic earth pressure acting on the underground walls of a deeply embedded nuclear reactor building. However, since this method was developed on the basis of the limit state of soil supported by retaining walls, the behavior of dynamic earth pressure acting on the embedded part of a nuclear reactor building may differ from the estimated by this method. This paper examines the fundamental characteristics of dynamic earth pressure through dynamic soil-structure interaction analysis. A simplified method to evaluate dynamic earth pressure for the design of underground walls of a nuclear reactor building is described. The dynamic earth pressure is fluctuating earth pressure during earthquake

Seismic Hazard Assessment for a Characteristic Earthquake Scenario: Probabilistic-Deterministic Method

Science.gov (United States)

mouloud, Hamidatou

2016-04-01

The objective of this paper is to analyze the seismic activity and the statistical treatment of seismicity catalog the Constantine region between 1357 and 2014 with 7007 seismic event. Our research is a contribution to improving the seismic risk management by evaluating the seismic hazard in the North-East Algeria. In the present study, Earthquake hazard maps for the Constantine region are calculated. Probabilistic seismic hazard analysis (PSHA) is classically performed through the Cornell approach by using a uniform earthquake distribution over the source area and a given magnitude range. This study aims at extending the PSHA approach to the case of a characteristic earthquake scenario associated with an active fault. The approach integrates PSHA with a high-frequency deterministic technique for the prediction of peak and spectral ground motion parameters in a characteristic earthquake. The method is based on the site-dependent evaluation of the probability of exceedance for the chosen strong-motion parameter. We proposed five sismotectonique zones. Four steps are necessary: (i) identification of potential sources of future earthquakes, (ii) assessment of their geological, geophysical and geometric, (iii) identification of the attenuation pattern of seismic motion, (iv) calculation of the hazard at a site and finally (v) hazard mapping for a region. In this study, the procedure of the earthquake hazard evaluation recently developed by Kijko and Sellevoll (1992) is used to estimate seismic hazard parameters in the northern part of Algeria.

LOO: a low-order nonlinear transport scheme for acceleration of method of characteristics

International Nuclear Information System (INIS)

Li, Lulu; Smith, Kord; Forget, Benoit; Ferrer, Rodolfo

2015-01-01

This paper presents a new physics-based multi-grid nonlinear acceleration method: the low-order operator method, or LOO. LOO uses a coarse space-angle multi-group method of characteristics (MOC) neutron transport calculation to accelerate the fine space-angle MOC calculation. LOO is designed to capture more angular effects than diffusion-based acceleration methods through a transport-based low-order solver. LOO differs from existing transport-based acceleration schemes in that it emphasizes simplified coarse space-angle characteristics and preserves physics in quadrant phase-space. The details of the method, including the restriction step, the low-order iterative solver and the prolongation step are discussed in this work. LOO shows comparable convergence behavior to coarse mesh finite difference on several two-dimensional benchmark problems while not requiring any under-relaxation, making it a robust acceleration scheme. (author)

Performance characteristics of a Vertical Axis Wind Turbine (VAWT) under transient conditions

OpenAIRE

Colley, Gareth; Mishra, Rakesh

2011-01-01

The present work investigates the performance characteristics of a novel Vertical Axis Wind Turbine (VAWT) for use in the urban environment. Here the performance of the wind turbine has been analyzed experimentally using a full scale prototype measuring 2.0m diameter and 1.0m in height. The turbine was located at the exit of a 0.6m x 0.6m wind tunnel section and was subjected to a jet flow. The performance output from the turbine has been obtained using a torque transducer unit which provides...

Performance and characteristics of carcass and non-carcass components of lambs fed peach-palm by-product.

Science.gov (United States)

dos Santos Cabral, Ícaro; Azevêdo, José Augusto Gomes; de Almeida, Flávio Moreira; Pereira, Luiz Gustavo Ribeiro; de Araújo, Gherman Garcia Leal; dos Santos Cruz, Cristiane Leal; Nogueira, Abdon Santos; Souza, Lígia Lins; de Oliveira, Gisele Andrade

2013-11-01

The objective of this study was to evaluate the effects of supplying the by-product of peach-palm (Bactris gasipaes) on performance and characteristics of carcass and non-carcass components of feedlot lambs. Twenty Santa Ines lambs of 150 days average age and 22.4 ± 3.4 kg body weight were confined in individual pens. A completely randomized design was utilized with four experimental diets composed of: fresh peach-palm by-product enriched with urea, fresh peach-palm by-product + concentrate, silage of peach-palm by-product + concentrate, and silage of peach-palm by-product enriched with 15 % corn meal + concentrate. Intake was evaluated daily, and at the end of 42 days of experiments, lambs were slaughtered and the characteristics of carcass and non-carcass parts were evaluated. Performance and carcass characteristics showed differences between the animals' intake of total mixed rations (TMR) and only the diet with roughage. For the lambs that intaked TMR, the form of utilization of roughage (fresh or as silage) affected animal performance but did not change the carcass characteristics. Dry matter intake and feed conversion were influenced by the form of utilization of the silage (with and without additive). Providing fresh by-product plus concentrate improves lamb performance but does not interfere in the carcass characteristics, compared with the use of by-product in the form of silage.

Effects of Selected Corporate Governance Characteristics on Firm Performance: Empirical Evidence from Kenya

Directory of Open Access Journals (Sweden)

Vincent Okoth Ongore

2011-01-01

Full Text Available This paper examines the interrelations among ownership, board and manager characteristics and firm performance in a sample of 54 firms listed at the Nairobi Stock Exchange (NSE. These governance characteristics, designed to minimize agency problems between principals and agents are operationalized in terms of ownership concentration, ownership identity, board effectiveness and managerial discretion. The typical ownership identities at the NSE are government, foreign, institutional, manager and diverse ownership forms. Firm performance is measured using Return on Assets (ROA, Return on Equity (ROE and Dividend Yield (DY. Using PPMC, Logistic Regression and Stepwise Regression, the paper presents evidence of significant positive relationship between foreign, insider, institutional and diverse ownership forms, and firm performance. However, the relationship between ownership concentration and government, and firm performance was significantly negative. The role of boards was found to be of very little value, mainly due to lack of adherence to board member selection criteria. The results also show significant positive relationship between managerial discretion and performance. Collectively, these results are consistent with pertinent literature with regard to the implications of government, foreign, manager (insider and institutional ownership forms, but significantly differ concerning the effects of ownership concentration and diverse ownership on firm performance.

Biological characteristics of crucian by quantitative inspection method

Science.gov (United States)

Chu, Mengqi

2015-04-01

Biological characteristics of crucian by quantitative inspection method Through quantitative inspection method , the biological characteristics of crucian was preliminary researched. Crucian , Belongs to Cypriniformes, Cyprinidae, Carassius auratus, is a kind of main plant-eating omnivorous fish,like Gregarious, selection and ranking. Crucian are widely distributed, perennial water all over the country all have production. Determine the indicators of crucian in the experiment, to understand the growth, reproduction situation of crucian in this area . Using the measured data (such as the scale length ,scale size and wheel diameter and so on) and related functional to calculate growth of crucian in any one year.According to the egg shape, color, weight ,etc to determine its maturity, with the mean egg diameter per 20 eggs and the number of eggs per 0.5 grams, to calculate the relative and absolute fecundity of the fish .Measured crucian were female puberty. Based on the relation between the scale diameter and length and the information, linear relationship between crucian scale diameter and length: y=1.530+3.0649. From the data, the fertility and is closely relative to the increase of age. The older, the more mature gonad development. The more amount of eggs. In addition, absolute fecundity increases with the pituitary gland.Through quantitative check crucian bait food intake by the object, reveals the main food, secondary foods, and chance food of crucian ,and understand that crucian degree of be fond of of all kinds of bait organisms.Fish fertility with weight gain, it has the characteristics of species and populations, and at the same tmes influenced by the age of the individual, body length, body weight, environmental conditions (especially the nutrition conditions), and breeding habits, spawning times factors and the size of the egg. After a series of studies of crucian biological character, provide the ecological basis for local crucian's feeding, breeding

Dynamic Performance Characteristic Tests of Real Scale Lead Rubber Bearing for the Evaluation of Performance Criteria

International Nuclear Information System (INIS)

Kim, Min Kyu; Kim, Jung-Han; Choi, In-Kil

2014-01-01

Dynamic characteristic tests of full scale lead rubber bearing were performed for the evaluation of performance criteria of isolation system for nuclear power plants. For the dynamic test for a full scale rubber bearing, two 1500mm diameter lead rubber bearings were manufactured. The viewpoints of this dynamic test are determination of an ultimate shear strain level of lead rubber bearing, behavior of rubber bearing according to static and dynamic input motion, sinusoidal and random (earthquake) motion, and 1-dimentional and 2-dimensional input motion. In this study, seismic isolation device tests were performed for the evaluation of performance criteria of isolation system. Through this test, it can be recognized that in the case of considering a mechanical property test, dynamic and multi degree of loading conditions should be determined. But these differences should be examined how much affect to the global structural behavior

Investigating the effect of communication characteristics on crew performance under the simulated emergency condition of nuclear power plants

International Nuclear Information System (INIS)

Park, Jinkyun; Jung, Wondea; Yang, Joon-Eon

2012-01-01

It is well known that the safety of large process control systems could be significantly affected by the communication characteristics of crews that have a responsibility for their operations. Accordingly, many researchers have spent huge amount of effort to grasp the relationship between the characteristics of crew communications and the associated crew performance. Unfortunately, in the case of nuclear power plants (NPPs), it seems that most of existing studies have tried to identify the relationship between the characteristics of crew communications and the associated crew performance using empirical observations without a firm technical underpinning. For these reasons, Park suggested a novel framework that is able to represent the characteristics of crew communications based on social network analysis (SNA) metrics. In order to confirm the appropriateness of the suggested framework, in this study, the characteristics of crew communications that are gathered from the simulated emergency condition of NPPs are additionally compared with the associated crew performance data. As a consequence, it is observed that there are significant relationships between communication characteristics and the associated crew performance. Therefore, it is reasonable to expect that the characteristics of crew communications can be properly grasped using the suggested framework. - Highlights: ► Communication data of MCR operating crews are collected from a simulated emergency condition. ► Communication characteristics are represented by the associated SNA metrics. ► Identified communication characteristics are compared with the results of existing studies. ► SNA metrics are meaningful for explaining the characteristics of crew communications.

78 FR 15112 - Rulemaking Advisory Committee; Transport Airplane Performance and Handling Characteristics-New Task

Science.gov (United States)

2013-03-08

... Committee; Transport Airplane Performance and Handling Characteristics--New Task AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of new task assignment for the Aviation Rulemaking Advisory Committee... findings. The Task The FAA tasked ARAC to consider several areas within the airplane performance and...

Dynamic load-sharing characteristic analysis of face gear power-split gear system based on tooth contact characteristics

Science.gov (United States)

Dong, Hao; Hu, Yahui

2018-04-01

The bend-torsion coupling dynamics load-sharing model of the helicopter face gear split torque transmission system is established by using concentrated quality standard, to analyzing the dynamic load-sharing characteristic. The mathematical models include nonlinear support stiffness, time-varying meshing stiffness, damping, gear backlash. The results showed that the errors collectively influenced the load sharing characteristics, only reduce a certain error, it is never fully reached the perfect loading sharing characteristics. The system load-sharing performance can be improved through floating shaft support. The above-method will provide a theoretical basis and data support for its dynamic performance optimization design.

Object-Based Dense Matching Method for Maintaining Structure Characteristics of Linear Buildings.

Science.gov (United States)

Su, Nan; Yan, Yiming; Qiu, Mingjie; Zhao, Chunhui; Wang, Liguo

2018-03-29

In this paper, we proposed a novel object-based dense matching method specially for the high-precision disparity map of building objects in urban areas, which can maintain accurate object structure characteristics. The proposed framework mainly includes three stages. Firstly, an improved edge line extraction method is proposed for the edge segments to fit closely to building outlines. Secondly, a fusion method is proposed for the outlines under the constraint of straight lines, which can maintain the building structural attribute with parallel or vertical edges, which is very useful for the dense matching method. Finally, we proposed an edge constraint and outline compensation (ECAOC) dense matching method to maintain building object structural characteristics in the disparity map. In the proposed method, the improved edge lines are used to optimize matching search scope and matching template window, and the high-precision building outlines are used to compensate the shape feature of building objects. Our method can greatly increase the matching accuracy of building objects in urban areas, especially at building edges. For the outline extraction experiments, our fusion method verifies the superiority and robustness on panchromatic images of different satellites and different resolutions. For the dense matching experiments, our ECOAC method shows great advantages for matching accuracy of building objects in urban areas compared with three other methods.

Object-Based Dense Matching Method for Maintaining Structure Characteristics of Linear Buildings

Directory of Open Access Journals (Sweden)

Nan Su

2018-03-01

Full Text Available In this paper, we proposed a novel object-based dense matching method specially for the high-precision disparity map of building objects in urban areas, which can maintain accurate object structure characteristics. The proposed framework mainly includes three stages. Firstly, an improved edge line extraction method is proposed for the edge segments to fit closely to building outlines. Secondly, a fusion method is proposed for the outlines under the constraint of straight lines, which can maintain the building structural attribute with parallel or vertical edges, which is very useful for the dense matching method. Finally, we proposed an edge constraint and outline compensation (ECAOC dense matching method to maintain building object structural characteristics in the disparity map. In the proposed method, the improved edge lines are used to optimize matching search scope and matching template window, and the high-precision building outlines are used to compensate the shape feature of building objects. Our method can greatly increase the matching accuracy of building objects in urban areas, especially at building edges. For the outline extraction experiments, our fusion method verifies the superiority and robustness on panchromatic images of different satellites and different resolutions. For the dense matching experiments, our ECOAC method shows great advantages for matching accuracy of building objects in urban areas compared with three other methods.

Performance characteristics of counter flow wet cooling towers

International Nuclear Information System (INIS)

Khan, Jameel-Ur-Rehman; Yaqub, M.; Zubair, Syed M.

2003-01-01

Cooling towers are one of the biggest heat and mass transfer devices that are in widespread use. In this paper, we use a detailed model of counter flow wet cooling towers in investigating the performance characteristics. The validity of the model is checked by experimental data reported in the literature. The thermal performance of the cooling towers is clearly explained in terms of varying air and water temperatures, as well as the driving potential for convection and evaporation heat transfer, along the height of the tower. The relative contribution of each mode of heat transfer rate to the total heat transfer rate in the cooling tower is established. It is demonstrated with an example problem that the predominant mode of heat transfer is evaporation. For example, evaporation contributes about 62.5% of the total rate of heat transfer at the bottom of the tower and almost 90% at the top of the tower. The variation of air and water temperatures along the height of the tower (process line) is explained on psychometric charts

Transonic Performance Characteristics of Several Jet Noise Suppressors

Science.gov (United States)

Schmeer, James W.; Salters, Leland B., Jr.; Cassetti, Marlowe D.

1960-01-01

An investigation of the transonic performance characteristics of several noise-suppressor configurations has been conducted in the Langley 16-foot transonic tunnel. The models were tested statically and over a Mach number range from 0.70 to 1.05 at an angle of attack of 0 deg. The primary jet total-pressure ratio was varied from 1.0 (jet off) to about 4.5. The effect of secondary air flow on the performance of two of the configurations was investigated. A hydrogen peroxide turbojet-engine simulator was used to supply the hot-jet exhaust. An 8-lobe afterbody with centerbody, short shroud, and secondary air had the highest thrust-minus-drag coefficients of the six noise-suppressor configurations tested. The 12-tube and 12-lobe afterbodies had the lowest internal losses. The presence of an ejector shroud partially shields the external pressure distribution of the 8-lobe after-body from the influence of the primary jet. A ring-airfoil shroud increased the static thrust of the annular nozzle but generally decreased the thrust minus drag at transonic Mach numbers.

Performance and cavitation characteristics of bi-directional hydrofoils

Science.gov (United States)

Nedyalkov, Ivaylo; Wosnik, Martin

2013-11-01

Tidal turbines extract energy from flows which reverse direction. One way to address this bi-directionality in horizontal axis turbines that avoid the use of complex and maintenance-intensive yaw or blade pitch mechanisms, is to design bi-directional blades which perform (equally) well in either flow direction. A large number of proposed hydrofoil designs were investigated using numerical simulations. Selected candidate foils were also tested (at various speeds and angles of attack) in the High-Speed Cavitation Tunnel (HICaT) at the University of New Hampshire. Lift and drag were measured using a force balance, and cavitation inception and desinence were recorded. Experimental and numerical results were compared, and the foils were compared to each other and to reference foils. Bi-directional hydrofoils may provide a feasible solution to the problem of reversing flow direction, when their performance and cavitation characteristics are comparable to those for unidirectional foils, and the penalty in decreased energy production is outweighed by the cost reduction due to lower complexity and respectively lower installation and maintenance costs.

Method for Measuring Small Nonlinearities of Electric Characteristics

DEFF Research Database (Denmark)

Guldbrandsen, Tom; Meyer, Niels I; Schjær-Jacobsen, Jørgen

1965-01-01

A method is described for measuring very small deviations from linearity in electric characteristics. The measurement is based on the harmonics generated by the nonlinear element when subjected to a sine wave signal. A special bridge circuit is used to balance out the undesired harmonics...... of the signal generator together with the first harmonic frequency. The set-up measures the small-signal value and the first and second derivative with respect to voltage. The detailed circuits are given for measuring nonlinearities in Ohmic and capacitive components. In the Ohmic case, a sensitivity...

An extended step characteristic method for solving the transport equation in general geometries

International Nuclear Information System (INIS)

DeHart, M.D.; Pevey, R.E.; Parish, T.A.

1994-01-01

A method for applying the discrete ordinates method to solve the Boltzmann transport equation on arbitrary two-dimensional meshes has been developed. The finite difference approach normally used to approximate spatial derivatives in extrapolating angular fluxes across a cell is replaced by direct solution of the characteristic form of the transport equation for each discrete direction. Thus, computational cells are not restricted to the geometrical shape of a mesh element characteristic of a given coordinate system. However, in terms of the treatment of energy and angular dependencies, this method resembles traditional discrete ordinates techniques. By using the method developed here, a general two-dimensional space can be approximated by an irregular mesh comprised of arbitrary polygons. Results for a number of test problems have been compared with solutions obtained from traditional methods, with good agreement. Comparisons include benchmarks against analytical results for problems with simple geometry, as well as numerical results obtained from traditional discrete ordinates methods by applying the ANISN and TWOTRAN-II computer programs

Some performance characteristics of a fluidized bed heat recovery unit

International Nuclear Information System (INIS)

Militzer, J.; Basu, P.; Adaikkappan, N.

1985-01-01

The advantages of using fluidized bed heat recovery units with diesel engines are well documented. Two of those are: significantly less tube fouling and heat transfer coefficient four to five time higher than that of conventional shell and tube heat exchangers. The high concentration of soot in the exhaust gases of diesel engines make fouling a major concern in design of any kind of heat recovery unit. In the experiment a conventional fluidized bed heat exchanger was connected to the exhaust of a diesel engine mounted on a dynamometer. With this arrangement it was possible to test the heat recovery unit under a wide range of operating conditions. The main objective of this experiment was the determination of the performance characteristics of the heat recovery unit, especially with reference to its heat transfer and fouling characteristics. (author)

Drag Reduction and Performance Improvement of Hydraulic Torque Converters with Multiple Biological Characteristics

Directory of Open Access Journals (Sweden)

Liu Chunbao

2016-01-01

Full Text Available Fish-like, dolphin-like, and bionic nonsmooth surfaces were employed in a hydraulic torque converter to achieve drag reduction and performance improvement, which were aimed at reducing profile loss, impacting loss and friction loss, respectively. YJSW335, a twin turbine torque converter, was bionically designed delicately. The biological characteristics consisted of fish-like blades in all four wheels, dolphin-like structure in the first turbine and the stator, and nonsmooth surfaces in the pump. The prediction performance of bionic YJSW335, obtained by computational fluid dynamics simulation, was improved compared with that of the original model, and then it could be proved that drag reduction had been achieved. The mechanism accounting for drag reduction of three factors was also investigated. After bionic design, the torque ratio and the highest efficiencies of YJSW335 were both advanced, which were very difficult to achieve through traditional design method. Moreover, the highest efficiency of the low speed area and high speed area is 85.65% and 86.32%, respectively. By economic matching analysis of the original and bionic powertrains, the latter can significantly reduce the fuel consumption and improve the operating economy of the loader.

Development of a high performance liquid chromatography method ...

African Journals Online (AJOL)

Development of a high performance liquid chromatography method for simultaneous ... Purpose: To develop and validate a new low-cost high performance liquid chromatography (HPLC) method for ..... Several papers have reported the use of ...

Construction Professionals Job Performance and Characteristics: A Comparison of Indigenous and Expatriate Construction Companies in Nigeria

Directory of Open Access Journals (Sweden)

Henry Ndubuisi Onukwube

2011-06-01

Job performance is considered one of the most important constructs in human resources management because it helps to explain the value and utility that each employee adds to the organisation. The professionals in the Nigerian construction companies are not exception to the perceived low job performance rate within the industry. Extant literature points to the fact that job characteristics of employees can account for variance in their job performance rate.This study compares the job performance rate and job characteristics of construction professionals in indigenous and expatriate construction companies with a view to establish a relationship between job performance and job characteristics of construction professionals. A total of 762 questionnaires were collected and used for the study.  Eighty one (81 construction companies, 50 (62% indigenous and 31 (38% expatriate were selected using stratified random sampling technique. Data collected were analysed using mean item score, spearman rank correlation, linear regression analysis where appropriate. Findings of the study revealed that the relationship between job characteristics and job performance of construction professionals in construction companies in Nigeria is positive but low and the correlation coefficient is higher in expatriate construction companies. Based on the above finding, the study recommends that construction companies in Nigeria should endeavour and improve on their current core job dimensions (task significance, skill variety, task identity, autonomy and feedback inherent in various jobs designed within their respective organizations as this will constitute as one of the variants that will improve the job performance rate of construction professionals.

The effect of individual characteristics of decision making and judgment on stock-flow performance

NARCIS (Netherlands)

Raaijmakers, S.; Korzilius, H.P.L.M.; Rouwette, E.A.J.A.; Vennix, J.A.M.

2012-01-01

Extending the line of research on stock-flow performance we examined the impact of personality characteristics on task performance. It was assumed that the need for cognition, the need for closure and the preference for intuition and deliberation would relate to individual variations in

Performance characteristics of NuVal and the Overall Nutritional Quality Index (ONQI).

Science.gov (United States)

Katz, David L; Njike, Valentine Y; Rhee, Lauren Q; Reingold, Arthur; Ayoob, Keith T

2010-04-01

Improving diets has considerable potential to improve health, but progress in this area has been limited, and advice to increase fruit and vegetable intake has largely gone unheeded. Our objective was to test the performance characteristics of the Overall Nutritional Quality Index (ONQI), a tool designed to help improve dietary patterns one well-informed choice at a time. The ONQI was developed by a multidisciplinary group of nutrition and public health scientists independent of food industry interests and is the basis for the NuVal Nutritional Guidance System. Dietary guidelines, existing nutritional scoring systems, and other pertinent scientific literature were reviewed. An algorithm incorporating >30 entries that represent both micro- and macronutrient properties of foods, as well as weighting coefficients representing epidemiologic associations between nutrients and health outcomes, was developed and subjected to consumer research and testing of performance characteristics. ONQI and expert panel rankings correlated highly (R = 0.92, P consumer testing, approximately 80% of >800 study participants indicated that the ONQI would influence their purchase intent. ONQI scoring distinguished the more-healthful DASH (Dietary Approaches to Stop Hypertension) diet (mean score: 46) from the typical American diet according to the National Health and Nutrition Examination Survey (NHANES) 2003-2006 (mean score: 26.5; P purchase patterns and significant correlation with health outcomes in large cohorts of men and women followed for decades. NuVal offers universally applicable nutrition guidance that is independent of food industry interests and is supported by consumer research and scientific evaluation of its performance characteristics.

''In situ'' electronic testing method of a neutron detector performance

International Nuclear Information System (INIS)

Gonzalez, J.M.; Levai, F.

1987-01-01

The method allows detection of any important change in the electrical characteristics of a neutron sensor channel. It checks the response signal produced by an electronic detector circuit when a pulse generator is connected as input signal in the high voltage supply. The electronic circuit compares the detector capacitance value, previously measured, against a reference value, which is adjusted in a window type comparator electronic circuit to detect any important degrading condition of the capacitance value in a detector-cable system. The ''in-situ'' electronic testing method of neutron detector performance has been verified in a laboratory atmosphere to be a potential method to detect any significant change in the capacitance value of a nuclear sensor and its connecting cable, also checking: detector disconnections, cable disconnections, length changes of the connecting cable, electric short-opened circuits in the sensor channel, and any electrical trouble in the detector-connector-cable system. The experimental practices were carried out by simulation of several electric changes in a nuclear sensor-cable system from a linear D.C. channel which measures reactor power during nuclear reactor operation. It was made at the Training Reactor Electronic Laboratory. The results and conclusions obtained at the Laboratory were proved, satisfactorily, in the Electronic Instrumentation of Budapest Technical University Training Reactor, Hungary

Class modality, student characteristics, and performance in a community college introductory STEM course

Science.gov (United States)

Fogle, Thomas Ty

Research on introductory STEM course performance has indicated that student characteristics (age, ethnicity and gender) and Grade Point Average (G.P.A.) can be predictive of student performance, and by implication, a correlation among these factors can help determine course design interventions to help certain types of students perform well in introductory STEM courses. The basis of this study was a community college Visual Basic programming course taught in both online and hybrid format. Beginning students in this course represented a diverse population residing in a large, mid-western, city and surrounding communities. Many of these students were defined as "at-Risk" or "non-traditional, which generally means any combination of socio-economic, cultural, family and employment factors that indicate a student is non-traditional. Research has shown these students struggle academically in technologically dense STEM courses, and may require student services and support to achieve their individual performance goals. The overall number in the study range was 392 distance students and 287 blended course students. The main question of this research was to determine to what extent student characteristics in a community college context, and previous success, as measured in overall G.P.A., were related to course performance in an introductory Visual Basic programming (STEM) course; and, whether or not a combination of these factors and course modality was predictive of success. The study employed a quantitative, quasi-experimental design to assess whether students' course performance was linked to course modality, student characteristics and overall G.P.A. The results indicated that the only predictor of student performance was overall G.P.A. Despite the research analyzed in Chapter 2, there was no statistically significant relationship to modality, age, ethnicity, or gender to performance in the course. Cognitive load is significant in a computer programming course and it

METHODS AND TECHNIQUES OF PREDICTION OF KEY PERFORMANCE INDICATORS FOR IMPLEMENTATION OF CHANGES IN MAINTENANCE ORGANISATION

Directory of Open Access Journals (Sweden)

Andrzej WIECZOREK

2012-01-01

Full Text Available The article presents the concept of how to assess the future state of the organization in the area of using and maintenance of technical means, basing on the combination of "classic" prognostic model with models ‐ components of the selected computer tools. Presentation of this concept was preceded by the definition and characteristics of maintenance key performance indicators. It also presents a requirements and method of KPIs selection.

Combining multiple FDG-PET radiotherapy target segmentation methods to reduce the effect of variable performance of individual segmentation methods

Energy Technology Data Exchange (ETDEWEB)

McGurk, Ross J. [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Bowsher, James; Das, Shiva K. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Lee, John A [Molecular Imaging and Experimental Radiotherapy Unit, Universite Catholique de Louvain, 1200 Brussels (Belgium)

2013-04-15

different between 128 Multiplication-Sign 128 and 256 Multiplication-Sign 256 grid sizes for either method (MJV, p= 0.0519; STAPLE, p= 0.5672) but was for SMASD values (MJV, p < 0.0001; STAPLE, p= 0.0164). The best individual method varied depending on object characteristics. However, both MJV and STAPLE provided essentially equivalent accuracy to using the best independent method in every situation, with mean differences in DSC of 0.01-0.03, and 0.05-0.12 mm for SMASD. Conclusions: Combining segmentations offers a robust approach to object segmentation in PET. Both MJV and STAPLE improved accuracy and were robust against the widely varying performance of individual segmentation methods. Differences between MJV and STAPLE are such that either offers good performance when combining volumes. Neither method requires a training dataset but MJV is simpler to interpret, easy to implement and fast.

A Novel Characteristic Frequency Bands Extraction Method for Automatic Bearing Fault Diagnosis Based on Hilbert Huang Transform

Directory of Open Access Journals (Sweden)

Xiao Yu

2015-11-01

Full Text Available Because roller element bearings (REBs failures cause unexpected machinery breakdowns, their fault diagnosis has attracted considerable research attention. Established fault feature extraction methods focus on statistical characteristics of the vibration signal, which is an approach that loses sight of the continuous waveform features. Considering this weakness, this article proposes a novel feature extraction method for frequency bands, named Window Marginal Spectrum Clustering (WMSC to select salient features from the marginal spectrum of vibration signals by Hilbert–Huang Transform (HHT. In WMSC, a sliding window is used to divide an entire HHT marginal spectrum (HMS into window spectrums, following which Rand Index (RI criterion of clustering method is used to evaluate each window. The windows returning higher RI values are selected to construct characteristic frequency bands (CFBs. Next, a hybrid REBs fault diagnosis is constructed, termed by its elements, HHT-WMSC-SVM (support vector machines. The effectiveness of HHT-WMSC-SVM is validated by running series of experiments on REBs defect datasets from the Bearing Data Center of Case Western Reserve University (CWRU. The said test results evidence three major advantages of the novel method. First, the fault classification accuracy of the HHT-WMSC-SVM model is higher than that of HHT-SVM and ST-SVM, which is a method that combines statistical characteristics with SVM. Second, with Gauss white noise added to the original REBs defect dataset, the HHT-WMSC-SVM model maintains high classification accuracy, while the classification accuracy of ST-SVM and HHT-SVM models are significantly reduced. Third, fault classification accuracy by HHT-WMSC-SVM can exceed 95% under a Pmin range of 500–800 and a m range of 50–300 for REBs defect dataset, adding Gauss white noise at Signal Noise Ratio (SNR = 5. Experimental results indicate that the proposed WMSC method yields a high REBs fault

Do firm characteristics influence mutual fund performance? An empirical study for European mutual funds

NARCIS (Netherlands)

de Jong, F.C.J.M.; Wingens, L.

2013-01-01

This study investigates the influence of fund management firm characteristics on mutual fund performance. Using a sample of European domiciled open-end equity funds for the period 1998-2008, this study finds that the funds of private companies have performed better than the funds of public

Performance of various mathematical methods for calculation of radioimmunoassay results

International Nuclear Information System (INIS)

Sandel, P.; Vogt, W.

1977-01-01

Interpolation and regression methods are available for computer aided determination of radioimmunological end results. We compared the performance of eight algorithms (weighted and unweighted linear logit-log regression, quadratic logit-log regression, Rodbards logistic model in the weighted and unweighted form, smoothing spline interpolation with a large and small smoothing factor and polygonal interpolation) on the basis of three radioimmunoassays with different reference curve characteristics (digoxin, estriol, human chorionic somatomammotropin = HCS). Great store was set by the accuracy of the approximation at the intermediate points on the curve, ie. those points that lie midway between two standard concentrations. These concentrations were obtained by weighing and inserted as unknown samples. In the case of digoxin and estriol the polygonal interpolation provided the best results while the weighted logit-log regression proved superior in the case of HCS. (orig.) [de

Performance characteristics of broilers fed graded levels of Moringa oleifera leaf meal

OpenAIRE

Ayo-Ajasa, O.Y.; Abiona, J.A.; Fafiolu, A.O.; Egbeyale, L.T.; Njoku1, C.P.; Omotayo1, I.G.; Odeyemi1, A.Y.; Abel, F.A.S.

2016-01-01

Cost of conventional protein sources is on the increase recently; hence, there is the need for cheaper alternative sources that will not compromise the performance characteristics of broiler birds taking into consideration the cost of production. Moringa leaf meal has been reported to increase the performance of broiler birds due to its rich protein content. Two hundred day-old broiler chicks were used to assess the effects of partial replacement of soya bean meal with Moringa (Moringa oleife...

Relationship of nurses' intrapersonal characteristics with work performance and caring behaviors: A cross-sectional study.

Science.gov (United States)

Geyer, Nelouise-Marié; Coetzee, Siedine K; Ellis, Suria M; Uys, Leana R

2018-02-28

This study aimed to describe intrapersonal characteristics (professional values, personality, empathy, and job involvement), work performance as perceived by nurses, and caring behaviors as perceived by patients, and to examine the relationships among these variables. A cross-sectional design was employed. A sample was recruited of 218 nurses and 116 patients in four private hospitals and four public hospitals. Data were collected using self-report measures. Data analysis included descriptive statistics, exploratory and confirmatory factor analyses, hierarchical linear modelling, correlations, and structural equation modeling. Nurses perceived their work performance to be of high quality. Among the intrapersonal characteristics, nurses had high scores for professional values, and moderately high scores for personality, empathy and job involvement. Patients perceived nurses' caring behaviors as moderately high. Professional values of nurses were the only selected intrapersonal characteristic with a statistically significant positive relationship, of practical importance, with work performance as perceived by nurses and with caring behaviors as perceived by patients at ward level. Managers can enhance nurses' work performance and caring behaviors through provision of in-service training that focuses on development of professional values. © 2018 John Wiley & Sons Australia, Ltd.

Identifying the performance characteristics of a winning outcome in elite mixed martial arts competition.

Science.gov (United States)

James, Lachlan P; Robertson, Sam; Haff, G Gregory; Beckman, Emma M; Kelly, Vincent G

2017-03-01

To determine those performance indicators that have the greatest influence on classifying outcome at the elite level of mixed martial arts (MMA). A secondary objective was to establish the efficacy of decision tree analysis in explaining the characteristics of victory when compared to alternate statistical methods. Cross-sectional observational. Eleven raw performance indicators from male Ultimate Fighting Championship bouts (n=234) from July 2014 to December 2014 were screened for analysis. Each raw performance indicator was also converted to a rate-dependent measure to be scaled to fight duration. Further, three additional performance indicators were calculated from the dataset and included in the analysis. Cohen's d effect sizes were employed to determine the magnitude of the differences between Wins and Losses, while decision tree (chi-square automatic interaction detector (CHAID)) and discriminant function analyses (DFA) were used to classify outcome (Win and Loss). Effect size comparisons revealed differences between Wins and Losses across a number of performance indicators. Decision tree (raw: 71.8%; rate-scaled: 76.3%) and DFA (raw: 71.4%; rate-scaled 71.2%) achieved similar classification accuracies. Grappling and accuracy performance indicators were the most influential in explaining outcome. The decision tree models also revealed multiple combinations of performance indicators leading to victory. The decision tree analyses suggest that grappling activity and technique accuracy are of particular importance in achieving victory in elite-level MMA competition. The DFA results supported the importance of these performance indicators. Decision tree induction represents an intuitive and slightly more accurate approach to explaining bout outcome in this sport when compared to DFA. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Distributed utility technology cost, performance, and environmental characteristics

Energy Technology Data Exchange (ETDEWEB)

Wan, Y; Adelman, S

1995-06-01

Distributed Utility (DU) is an emerging concept in which modular generation and storage technologies sited near customer loads in distribution systems and specifically targeted demand-side management programs are used to supplement conventional central station generation plants to meet customer energy service needs. Research has shown that implementation of the DU concept could provide substantial benefits to utilities. This report summarizes the cost, performance, and environmental and siting characteristics of existing and emerging modular generation and storage technologies that are applicable under the DU concept. It is intended to be a practical reference guide for utility planners and engineers seeking information on DU technology options. This work was funded by the Office of Utility Technologies of the US Department of Energy.

A mathematical modeling method for determination of local vibroacoustic characteristics of structures

Science.gov (United States)

Tartakovskiy, B. D.; Dubner, A. B.

1973-01-01

A method is proposed for determining vibroacoustic characteristics from the results of measurements of the distribution of vibrational energy in a structure. The method is based on an energy model of a structure studied earlier. Equations are written to describe the distribution of vibrational energy in a hypothetical diffuse energy state in structural elements.

Relationship between musical characteristics and temporal breathing pattern in piano performance

Directory of Open Access Journals (Sweden)

Yutaka Sakaguchi

2016-07-01

Full Text Available Although there is growing evidence that breathing is modulated by various motor and cognitive activities, the nature of breathing in musical performance has been little explored. The present study examined the temporal breath pattern in piano performance, aiming to elucidate how breath timing is related to musical organization/events and performance. In the experiments, the respiration of 15 professional and amateur pianists, playing 10 music excerpts in total (from four-octave C major scale, Hanon’s exercise, J. S. Bach’s Invention, Mozart’s Sonatas, and Debussy’s Clair de lune, was monitored by capnography. The relationship between breathing and musical characteristics was analyzed. Five major results were obtained. 1 Mean breath interval was shortened for excerpts in faster tempi. 2 Fluctuation of breath intervals was reduced for the pieces for finger exercise and those in faster tempi. Pianists showing large within-trial fluctuation also exhibited large inter-excerpt difference. 3 Inter-trial consistency of the breath patterns depended on the excerpts. Consistency was generally reduced for the excerpts that could be performed mechanically (i.e., pieces for finger exercise, but interestingly, one third of the participant showed consistent patterns for the simple scale, correlated with the ascending/descending sequences. 4 Pianists tended to exhale just after the music onsets, inhale at the rests, and inhibit inhale during the slur parts. There was correlation between breathing pattern and two-voice polyphonic structure for several participants. 5 Respiratory patterns were notably different among the pianists. Every pianist showed his or her own characteristic features commonly for various musical works. These findings suggest that breathing in piano performance depends not only on musical parameters and organization written in the score but also some pianist-dependent factors which might be ingrained to individual pianists.

Relationship between Musical Characteristics and Temporal Breathing Pattern in Piano Performance.

Science.gov (United States)

Sakaguchi, Yutaka; Aiba, Eriko

2016-01-01

Although there is growing evidence that breathing is modulated by various motor and cognitive activities, the nature of breathing in musical performance has been little explored. The present study examined the temporal breath pattern in piano performance, aiming to elucidate how breath timing is related to musical organization/events and performance. In the experiments, the respiration of 15 professional and amateur pianists, playing 10 music excerpts in total (from four-octave C major scale, Hanon's exercise, J. S. Bach's Invention, Mozart's Sonatas, and Debussy's Clair de lune), was monitored by capnography. The relationship between breathing and musical characteristics was analyzed. Five major results were obtained. (1) Mean breath interval was shortened for excerpts in faster tempi. (2) Fluctuation of breath intervals was reduced for the pieces for finger exercise and those in faster tempi. Pianists showing large within-trial fluctuation also exhibited large inter-excerpt difference. (3) Inter-trial consistency of the breath patterns depended on the excerpts. Consistency was generally reduced for the excerpts that could be performed mechanically (i.e., pieces for finger exercise), but interestingly, one third of the participant showed consistent patterns for the simple scale, correlated with the ascending/descending sequences. (4) Pianists tended to exhale just after the music onsets, inhale at the rests, and inhibit inhale during the slur parts. There was correlation between breathing pattern and two-voice polyphonic structure for several participants. (5) Respiratory patterns were notably different among the pianists. Every pianist showed his or her own characteristic features commonly for various musical works. These findings suggest that breathing in piano performance depends not only on musical parameters and organization written in the score but also some pianist-dependent factors which might be ingrained to individual pianists.

METRIC CHARACTERISTICS OF VARIOUS METHODS FOR NUMERICAL DENSITY ESTIMATION IN TRANSMISSION LIGHT MICROSCOPY – A COMPUTER SIMULATION

Directory of Open Access Journals (Sweden)

Miroslav Kališnik

2011-05-01

Full Text Available In the introduction the evolution of methods for numerical density estimation of particles is presented shortly. Three pairs of methods have been analysed and compared: (1 classical methods for particles counting in thin and thick sections, (2 original and modified differential counting methods and (3 physical and optical disector methods. Metric characteristics such as accuracy, efficiency, robustness, and feasibility of methods have been estimated and compared. Logical, geometrical and mathematical analysis as well as computer simulations have been applied. In computer simulations a model of randomly distributed equal spheres with maximal contrast against surroundings has been used. According to our computer simulation all methods give accurate results provided that the sample is representative and sufficiently large. However, there are differences in their efficiency, robustness and feasibility. Efficiency and robustness increase with increasing slice thickness in all three pairs of methods. Robustness is superior in both differential and both disector methods compared to both classical methods. Feasibility can be judged according to the additional equipment as well as to the histotechnical and counting procedures necessary for performing individual counting methods. However, it is evident that not all practical problems can efficiently be solved with models.

The effect of management team characteristics on performance and style extremity of mutual fund portfolios

Directory of Open Access Journals (Sweden)

Liu Qiong

2014-01-01

Full Text Available Purpose: Along with mutual funds’ scale and quantity expanding for our country, it is common for fund management companies hiring new managers or the original fund managers mobilizing from one to another. The high liquidity of fund managers makes different managers regroup to manage the funds that belong to the same fund management company in each fund year. The characteristics of these different management team will influence the fund performance, and also affect the earnings of the fund management company and portfolio investors. The purpose of this paper is as follows. First, evaluating the effect of management team characteristics on portfolio characteristics: risk, performance, and extremity. Second, testing the hypothesis that the ranking of mid-year performance have effect on investment style extremity and research what relationship exists between this phenomenon and management team characteristics in depth.Design/methodology/approach: On the analysis of the relationships between the management team characteristics and portfolio characteristics, a series of OLS regressions is run where the time series regression model (the factor model and cross-sectional regression are included based on using the STATA, EVIEWS and MATLAB. The validity and practicability of the model will be verified in the paper. All of the above are aimed at achieving portfolio optimization and realizing the maximization of the interests of fund management companies and investors.Findings: The main findings are as follows. Teams with more doctors or MBA (CPA and CFA hold more risky portfolios, while teams with long team tenure hold less. More members and large gender diversity have negative effect on performance, and the opposite is age diversity. Teams with more members and long tenure tend to hold less extreme style decisions, but age diversity is related to more. Besides, tournament hypothesis does exist in China investment funds industry especially when the

The influence of tyre characteristics on measures of rolling performance during cross-country mountain biking.

Science.gov (United States)

Macdermid, Paul William; Fink, Philip W; Stannard, Stephen R

2015-01-01

This investigation sets out to assess the effect of five different models of mountain bike tyre on rolling performance over hard-pack mud. Independent characteristics included total weight, volume, tread surface area and tread depth. One male cyclist performed multiple (30) trials of a deceleration field test to assess reliability. Further tests performed on a separate occasion included multiple (15) trials of the deceleration test and six fixed power output hill climb tests for each tyre. The deceleration test proved to be reliable as a means of assessing rolling performance via differences in initial and final speed (coefficient of variation (CV) = 4.52%). Overall differences between tyre performance for both deceleration test (P = 0.014) and hill climb (P = 0.032) were found, enabling significant (P < 0.0001 and P = 0.049) models to be generated, allowing tyre performance prediction based on tyre characteristics. The ideal tyre for rolling and climbing performance on hard-pack surfaces would be to decrease tyre weight by way of reductions in tread surface area and tread depth while keeping volume high.

Novel method to control antenna currents based on theory of characteristic modes

Science.gov (United States)

Elghannai, Ezdeen Ahmed

Characteristic Mode Theory is one of the very few numerical methods that provide a great deal of physical insight because it allows us to determine the natural modes of the radiating structure. The key feature of these modes is that the total induced antenna current, input impedance/admittance and radiation pattern can be expressed as a linear weighted combination of individual modes. Using this decomposition method, it is possible to study the behavior of the individual modes, understand them and therefore control the antennas behavior; in other words, control the currents induced on the antenna structure. This dissertation advances the topic of antenna design by carefully controlling the antenna currents over the desired frequency band to achieve the desired performance specifications for a set of constraints. Here, a systematic method based on the Theory of Characteristic Modes (CM) and lumped reactive loading to achieve the goal of current control is developed. The lumped reactive loads are determined based on the desired behavior of the antenna currents. This technique can also be used to impedance match the antenna to the source/generator connected to it. The technique is much more general than the traditional impedance matching. Generally, the reactive loads that properly control the currents exhibit a combination of Foster and non-Foster behavior. The former can be implemented with lumped passive reactive components, while the latter can be implemented with lumped non-Foster circuits (NFC). The concept of current control is applied to design antennas with a wide band (impedance/pattern) behavior using reactive loads. We successfully applied this novel technique to design multi band and wide band antennas for wireless applications. The technique was developed to match the antenna to resistive and/or complex source impedance and control the radiation pattern at these frequency bands, considering size and volume constraints. A wide band patch antenna was

Ion counting method and it's operational characteristics in gas chromatography-mass spectrometry

International Nuclear Information System (INIS)

Fujii, Toshihiro

1976-01-01

Ion counting method with continuous channel electron multiplier which affords the direct detection of very small ion currents and it's operational characteristics were studied in gas chromatography-mass spectrometry. Then this method was applied to the single ion detection technique of GC-MS. A detection limit was measured, using various standard samples of low level concentration. (auth.)

Hospital Value-Based Purchasing Performance: Do Organizational and Market Characteristics Matter?

Science.gov (United States)

Spaulding, Aaron; Edwardson, Nick; Zhao, Mei

The hospital value-based purchasing (HVBP) program of the Centers for Medicare & Medicaid Services challenges hospitals to deliver high-quality care or face a reduction in Medicare payments. How do different organizational structures and market characteristics enable or inhibit successful transition to this new model of value-based care? To address that question, this study employs an institutional theory lens to test whether certain organizational structures and market characteristics mediate hospitals' ability to perform across HVBP domains.Data from the 2014 American Hospital Association Annual Survey Database, Area Health Resource File, the Medicare Hospital Compare Database, and the association between external environment and hospital performance are assessed through multiple regression analysis. Results indicate that hospitals that belong to a system are more likely than independent hospitals to score highly on the domains associated with the HVBP incentive arrangement. However, varying and sometimes counterintuitive market influences bring different dimensions to the HVBP program. A hospital's ability to score well in this new value arrangement may be heavily based on the organization's ability to learn from others, implement change, and apply the appropriate amount of control in various markets.

Performance characteristics of solar air heater with surface mounted obstacles

International Nuclear Information System (INIS)

Bekele, Adisu; Mishra, Manish; Dutta, Sushanta

2014-01-01

Highlights: • Solar air heater with delta shaped obstacles have been studied. • Obstacle angle of incidence strongly affects the thermo-hydraulic performance. • Thermal performance of obstacle mounted collectors is superior to smooth collectors. • Thermo-hydraulic performance of the present SAH is higher than those in previous studies. - Abstract: The performance of conventional solar air heaters (SAHs) can be improved by providing obstacles on the heated wall (i.e. on the absorber plate). Experiments have been performed to collect heat transfer and flow-friction data from an air heater duct with delta-shaped obstacles mounted on the absorber surface and having an aspect ratio 6:1 resembling the conditions close to the solar air heaters. This study encompassed for the range of Reynolds number (Re) from 2100 to 30,000, relative obstacle height (e/H) from 0.25 to 0.75, relative obstacle longitudinal pitch (P l /e) from 3/2 to 11/2, relative obstacle transverse pitch (P t /b) from 1 to 7/3 and the angle of incidence (α) varied from 30° to 90°. The thermo-hydraulic performance characteristics of SAH have been compared with the previous published works and the optimum range of the geometries have been explored for the better performance of such air-heaters compared to the other designs of solar air heaters

A New Identification Method of Both Magnetization Characteristic and Parameters of an Unloaded Transformer

Directory of Open Access Journals (Sweden)

Petr Orsag

2008-01-01

Full Text Available In this paper a new method of identification of both the magnetization characteristic and the instantaneous parameters G(t and K(t of a single-phase transformer under a sinusoidal supply voltage is proposed. The instantaneous conductance G(t and inverse inductance K(t of the transformer cross section are determined by the scalar product of time functions. The magnetization characteristic is derived by means of the inverse inductance K(t. The method is practically applied to an isolating transformer.

Adsorption characteristics of methane on Maxsorb III by gravimetric method

KAUST Repository

Thu, Kyaw

2014-11-01

Adsorption characteristics of CH4 on the carbonaceous porous material is evaluated for possible application in adsorbed natural gas (ANG) system. Adsorption uptakes at assorted temperatures (25-80 °C) and pressures ranging from ambient to relatively high pressure i.e., 8.0 MPa are experimentally investigated. Surface characteristics such as pore surface area, micropore volume and pore size distribution of the adsorbent (Maxsorb III) are first evaluated using Classical Volumetric Method i.e., the manometric method with N2 gas adsorption at 77 K. The sorption measurements for methane, CH4 gas are carried out by thermogravimetric (TGA) method using magnetic suspension balance coupled with the automatic dosing system. The buoyancy measurements were first conducted using Helium gas as adsorbate. Buoyancy correction is applied to all sets of measured data and the specific uptake capacities (g/g of adsorbent) at various temperatures and pressures were calculated. The isotherm data were then fitted using Langmuir and Tòth isotherm models. It is observed that the data can be satisfactorily fitted using Tòth model with excellent fitting accuracy around 2.2% within the experimental range. The outcome of the present study especially the adsorption data at high pressures is applicable to accurate design and modeling of Adsorbed Natural Gas (ANG) systems. © 2014 Elsevier Ltd. All rights reserved.

One-dimensional calculation of flow branching using the method of characteristics

International Nuclear Information System (INIS)

Meier, R.W.; Gido, R.G.

1978-05-01

In one-dimensional flow systems, the flow often branches, such as at a tee or manifold. The study develops a formulation for calculating the flow through branch points with one-dimensional method of characteristics equations. The resultant equations were verified by comparison with experimental measurements

Performance of adsorbent-embedded heat exchangers using binder-coating method

KAUST Repository

Li, Ang

2016-01-01

The performance of adsorption (AD) chillers or desalination cycles is dictated by the rates of heat and mass transfer of adsorbate in adsorbent-packed beds. Conventional granular-adsorbent, packed in fin-tube heat exchangers, suffered from poor heat transfer in heating (desorption) or cooling (adsorption) processes of the batch-operated cycles, with undesirable performance parameters such as higher footprint of plants, low coefficient of performance (COP) of AD cycles and higher capital cost of the machines. The motivation of present work is to mitigate the heat and mass "bottlenecks" of fin-tube heat exchangers by using a powdered-adsorbent cum binder coated onto the fin surfaces of exchangers. Suitable adsorbent-binder pairs have been identified for the silica gel adsorbent with pore surface areas up to 680 m2/g and pore diameters less than 6 nm. The parent silica gel remains largely unaffected despite being pulverized into fine particles of 100 μm, and yet maintaining its water uptake characteristics. The paper presents an experimental study on the selection and testing processes to achieve high efficacy of adsorbent-binder coated exchangers. The test results indicate 3.4-4.6 folds improvement in heat transfer rates over the conventional granular-packed method, resulting a faster rate of water uptake by 1.5-2 times on the suitable silica gel type. © 2015 Elsevier Ltd. All rights reserved.

EXPERIMENTAL ANALYSIS OF THE CHARACTERISTIC PERFORMANCE OF STANDALONE PHOTOVOLTAIC SYSTEM

OpenAIRE

Birendra Kishore; Anirban Nandy*; O.P. Pandey

2016-01-01

This paper demonstrates an insight solar PV Stand Alone system which is a practical model with a halogen light source. At different situations the performance of solar PV cells are analyzed. The system produces power with depending on the change in halogen light intensity & temperature. A theoretical & experimental analysis of the PV cell can be achieved. In this paper the I-V & P-V characteristic of the solar photovoltaic cells with changes in temperature and isolation have been showed. With...

Three-dimensional ordered particulate structures: Method to retrieve characteristics from photonic band gap data

International Nuclear Information System (INIS)

Miskevich, Alexander A.; Loiko, Valery A.

2015-01-01

A method to retrieve characteristics of ordered particulate structures, such as photonic crystals, is proposed. It is based on the solution of the inverse problem using data on the photonic band gap (PBG). The quasicrystalline approximation (QCA) of the theory of multiple scattering of waves and the transfer matrix method (TMM) are used. Retrieval of the refractive index of particles is demonstrated. Refractive indices of the artificial opal particles are estimated using the published experimental data. - Highlights: • A method to retrieve characteristics of photonic crystals is proposed. • The method is based on the inverse problem solution using the photonic band gap data. • Retrieval of the refractive index of photonic crystal particles is demonstrated. • Retrieval results show inhomogeneous distribution of synthetic opal particle pores

Robust Navier-Stokes method for predicting unsteady flowfield and aerodynamic characteristics of helicopter rotor

Directory of Open Access Journals (Sweden)

Qijun ZHAO

2018-02-01

Full Text Available A robust unsteady rotor flowfield solver CLORNS code is established to predict the complex unsteady aerodynamic characteristics of rotor flowfield. In order to handle the difficult problem about grid generation around rotor with complex aerodynamic shape in this CFD code, a parameterized grid generated method is established, and the moving-embedded grids are constructed by several proposed universal methods. In this work, the unsteady Reynolds-Averaged Navier-Stokes (RANS equations with Spalart-Allmaras are selected as the governing equations to predict the unsteady flowfield of helicopter rotor. The discretization of convective fluxes is accomplished by employing the second-order central difference scheme, third-order MUSCL-Roe scheme, and fifth-order WENO-Roe scheme. Aimed at simulating the unsteady aerodynamic characteristics of helicopter rotor, the dual-time scheme with implicit LU-SGS scheme is employed to accomplish the temporal discretization. In order to improve the computational efficiency of hole-cells and donor elements searching of the moving-embedded grid technology, the “disturbance diffraction method” and “minimum distance scheme of donor elements method” are established in this work. To improve the computational efficiency, Message Passing Interface (MPI parallel method based on subdivision of grid, local preconditioning method and Full Approximation Storage (FAS multi-grid method are combined in this code. By comparison of the numerical results simulated by CLORNS code with test data, it is illustrated that the present code could simulate the aerodynamic loads and aerodynamic noise characteristics of helicopter rotor accurately. Keywords: Aerodynamic characteristics, Helicopter rotor, Moving-embedded grid, Navier-Stokes equations, Upwind schemes

Experimental studies on the combustion characteristics and performance of a direct injection engine fueled with biodiesel/diesel blends

International Nuclear Information System (INIS)

Qi, D.H.; Chen, H.; Geng, L.M.; Bian, Y. ZH.

2010-01-01

Biodiesel is an alternative diesel fuel that can be produced from different kinds of vegetable oils. It is an oxygenated, non-toxic, sulphur-free, biodegradable, and renewable fuel and can be used in diesel engines without significant modification. However, the performance, emissions and combustion characteristics will be different for the same biodiesel used in different types of engine. In this study, the biodiesel produced from soybean crude oil was prepared by a method of alkaline-catalyzed transesterification. The effects of biodiesel addition to diesel fuel on the performance, emissions and combustion characteristics of a naturally aspirated DI compression ignition engine were examined. Biodiesel has different properties from diesel fuel. A minor increase in brake specific fuel consumption (BSFC) and decrease in brake thermal efficiency (BTE) for biodiesel and its blends were observed compared with diesel fuel. The significant improvement in reduction of carbon monoxide (CO) and smoke were found for biodiesel and its blends at high engine loads. Hydrocarbon (HC) had no evident variation for all tested fuels. Nitrogen oxides (NOx) were slightly higher for biodiesel and its blends. Biodiesel and its blends exhibited similar combustion stages to diesel fuel. The use of transesterified soybean crude oil can be partially substituted for the diesel fuel at most operating conditions in terms of the performance parameters and emissions without any engine modification.

Effects of Pretreatment Methods on Electrodes and SOFC Performance

Directory of Open Access Journals (Sweden)

Guo-Bin Jung

2014-06-01

Full Text Available Commercially available tapes (anode, electrolyte and paste (cathode were choosen to prepare anode-supported cells for solid oxide fuel cell applications. For both anode-supported cells or electrolyte-supported cells, the anode needs pretreatment to reduce NiO/YSZ to Ni/YSZ to increase its conductivity as well as its catalytic characteristics. In this study, the effects of different pretreatments (open-circuit, closed-circuit on cathode and anodes as well as SOFC performance are investigated. To investigate the influence of closed-circuit pretreatment on the NiO/YSZ anode alone, a Pt cathode is utilized as reference for comparison with the LSM cathode. The characterization of the electrical resistance, AC impedance, and SOFC performance of the resulting electrodes and/or anode-supported cell were carried out. It’s found that the influence of open-circuit pretreatment on the LSM cathode is limited. However, the influence of closed-circuit pretreatment on both the LSM cathode and NiO/YSZ anode and the resulting SOFC performance is profound. The effect of closed-circuit pretreatment on the NiO/YSZ anode is attributed to its change of electronic/pore structure as well as catalytic characteristics. With closed-circuit pretreatment, the SOFC performance improved greatly from the change of LSM cathode (and Pt reference compared to the Ni/YSZ anode.

Performance and emission characteristics of double biodiesel blends with diesel

Directory of Open Access Journals (Sweden)

Kuthalingam Arun Balasubramanian

2013-01-01

Full Text Available Recent research on biodiesel focused on performance of single biodiesel and its blends with diesel. The present work aims to investigate the possibilities of the application of mixtures of two biodiesel and its blends with diesel as a fuel for diesel engines. The combinations of Pongamia pinnata biodiesel, Mustard oil biodiesel along with diesel (PMD and combinations of Cotton seed biodiesel, Pongamia pinnata biodiesel along with diesel (CPD are taken for the experimental analysis. Experiments are conducted using a single cylinder direct-injection diesel engine with different loads at rated 3000 rpm. The engine characteristics of the two sets of double biodiesel blends are compared. For the maximum load, the value of Specific Fuel consumption and thermal efficiency of CPD-1 blend (10:10:80 is close to the diesel values. CPD blends give better engine characteristics than PMD blends. The blends of CPD are suitable alternative fuel for diesel in stationary/agricultural diesel engines.

Development of methods for measuring materials nuclear characteristics, Phases, I, II, II and IV; Razvijanje metoda merenja nuklearnih karakteristika materijala, I, II, II i VI faza

Energy Technology Data Exchange (ETDEWEB)

Maglic, R [Boris Kidric Institute of Nuclear Sciences Vinca, Belgrade (Yugoslavia)

1963-04-15

This report contains the following phases of the project 'measurement of nuclear characteristics of reactor materials': nuclear performances of the neutron chopper; method for measuring total effective cross sections by transmission method on the chopper; review of methods for measuring activation cross sections; measurement of neutron spectra of the RA reactor and measurement of total effective cross section of gold by using the chopper.

Improvement of numerical analysis method for FBR core characteristics. 3

International Nuclear Information System (INIS)

Takeda, Toshikazu; Yamamoto, Toshihisa; Kitada, Takanori; Katagi, Yousuke

1998-03-01

As the improvement of numerical analysis method for FBR core characteristics, studies on several topics have been conducted; multiband method, Monte Carlo perturbation and nodal transport method. This report is composed of the following three parts. Part 1: Improvement of Reaction Rate Calculation Method in the Blanket Region Based on the Multiband Method; A method was developed for precise evaluation of the reaction rate distribution in the blanket region using the multiband method. With the 3-band parameters obtained from the ordinary fitting method, major reaction rates such as U-238 capture, U-235 fission, Pu-239 fission and U-238 fission rate distributions were analyzed. Part 2: Improvement of Estimation Method for Reactivity Based on Monte-Carlo Perturbation Theory; Perturbation theory based on Monte-Carlo perturbation theory have been investigated and introduced into the calculational code. The Monte-Carlo perturbation code was applied to MONJU core and the calculational results were compared to the reference. Part 3: Improvement of Nodal Transport Calculation for Hexagonal Geometry; A method to evaluate the intra-subassembly power distribution from the nodal averaged neutron flux and surface fluxes at the node boundaries, was developed based on the transport theory. (J.P.N.)

Evaluation of the dosimetric performance characteristic of fluoroscopy system used in medicine

International Nuclear Information System (INIS)

Qi Xuesong; Wei Kedao; Cheng Yuxi; Zhou Qifu; Ge Lijuan; Hou Changsong

2001-01-01

Objective: To discuss establishment of diagnostic reference dose value in fluoroscopic examinations for survey of 16 different types of fluoroscopy systems. Methods: Choosing dosimetric characteristic parameters including: IIESDR, ESDR (typical value) and ESDR max (ESDR maximum), and DAP, which was calibrated in situ on the X-ray unit. Results: Results of dose survey are summarized in three tables, from these we could get wide changes in accordance with those in many other countries resulting from maximum and minimum of IIESDR, ESDR and ESDRmax when measurements were performed at same entrance field size on I.I. Image Intensifier of the 15 fluoroscopy systems and under conditions of ABC. And also we could get less changes of DAP mean values, though differences for patient weight, technological parameters of fluoroscopic exam setting, fluoroscopic time and number of film were more remarkable. Conclusions: Measurements on IIESDR, ESDR (typical value) and ESDRmax (ESDR maximum) are not satisfied as diagnostic reference level. But it is suggested that DAP values, in fluoroscopic exam, are used as a tool to achieve this. (author)

Performance characteristics of a continuous-flow fluidic pump

International Nuclear Information System (INIS)

Robinson, S.M.; Counce, R.M.; Smith, G.V.

1987-01-01

The fluidic pump is a type of positive-displacement pump in which basic fluid mechanics phenomena are utilized to eliminate valves and other moving parts that are exposed to the fluid being transferred. The version described in this article is powered by gas pressure serving as gas pistons and is virtually maintenance-free. It utilizes two displacement vessels and is designed to produce a steady and continuous liquid flow. This type of pump may be very useful for the transfer of radioactive or hazardous liquids where mechanical maintenance may be difficult or exposure of personnel to the fluid is undesirable. This paper presents experimental and model-predicted characteristics of such systems. The effects of several geometric parameters and operating conditions on the performance of the pump are briefly discussed

Effects of dimethyl ether on the performance characteristics of a direct methanol fuel cell

International Nuclear Information System (INIS)

Seo, Sang Hern; Lee, Chang Sik

2013-01-01

Highlights: • Activation loss is significantly reduced in fuel cell with DME-methanol. • DME crossover through the membrane reduces. • The open circuit voltage of DME-methanol the fuel cell increases. • The overall efficiency of the mixed fuel cell is higher than that of DMFC. - Abstract: The objective of this study was to determine the effects of dimethyl ether (DME) on the performance characteristics of a direct methanol fuel cell. Impedance and crossover experiments were performed in order to investigate the performance losses such as ohmic loss, activation loss and crossover loss accurately. The DME was pressurized to 5 bar to supply with liquid phase was and blended with an aqueous methanol solution. In this experiment, the membrane electrode assembly (MEA) was composed of Nafion 115, anode catalyst loaded Pt–Ru and cathode catalyst loaded Pt-Black. Experimental results showed that fuel cells with DME-methanol enhanced performance when compared to fuel cells with methanol only. Such performance enhancement was due to a decrease in activation losses by DME oxidation reactions. As the DME crossover through the membrane was reduced, the open circuit voltage (OCV) of the fuel cell increased. Other output characteristics are also discussed

Comparison of different methods for the determination of dynamic characteristics of low velocity anemometers

DEFF Research Database (Denmark)

Melikov, Arsen Krikor; Popiolek, Z.

2004-01-01

Three methods for determining the dynamic characteristics of low velocity thermal anemometers were compared. They were: step-up velocity change and step-down velocity change methods and a method based on sinusoidal type velocity fluctuations. Two low velocity thermal anemometers with omnidirectio......Three methods for determining the dynamic characteristics of low velocity thermal anemometers were compared. They were: step-up velocity change and step-down velocity change methods and a method based on sinusoidal type velocity fluctuations. Two low velocity thermal anemometers...... with omnidirectional velocity sensors were tested. The results identify differences in frequency response of low velocity anemometers determined by the three methods. The time constant and the response time determined by the step-up velocity change method and the step-down velocity change method may be substantially...... different and insufficient for describing the frequency response of all low velocity thermal anemometers. Therefore the upper frequency, determined in tests with sinusoidal velocity fluctuations, is recommended to be used in indoor climate standards as a single parameter describing the dynamic...

The OpenMOC method of characteristics neutral particle transport code

International Nuclear Information System (INIS)

Boyd, William; Shaner, Samuel; Li, Lulu; Forget, Benoit; Smith, Kord

2014-01-01

Highlights: • An open source method of characteristics neutron transport code has been developed. • OpenMOC shows nearly perfect scaling on CPUs and 30× speedup on GPUs. • Nonlinear acceleration techniques demonstrate a 40× reduction in source iterations. • OpenMOC uses modern software design principles within a C++ and Python framework. • Validation with respect to the C5G7 and LRA benchmarks is presented. - Abstract: The method of characteristics (MOC) is a numerical integration technique for partial differential equations, and has seen widespread use for reactor physics lattice calculations. The exponential growth in computing power has finally brought the possibility for high-fidelity full core MOC calculations within reach. The OpenMOC code is being developed at the Massachusetts Institute of Technology to investigate algorithmic acceleration techniques and parallel algorithms for MOC. OpenMOC is a free, open source code written using modern software languages such as C/C++ and CUDA with an emphasis on extensible design principles for code developers and an easy to use Python interface for code users. The present work describes the OpenMOC code and illustrates its ability to model large problems accurately and efficiently

Research on Radiation Characteristic of Plasma Antenna through FDTD Method

Directory of Open Access Journals (Sweden)

Jianming Zhou

2014-01-01

Full Text Available The radiation characteristic of plasma antenna is investigated by using the finite-difference time-domain (FDTD approach in this paper. Through using FDTD method, we study the propagation of electromagnetic wave in free space in stretched coordinate. And the iterative equations of Maxwell equation are derived. In order to validate the correctness of this method, we simulate the process of electromagnetic wave propagating in free space. Results show that electromagnetic wave spreads out around the signal source and can be absorbed by the perfectly matched layer (PML. Otherwise, we study the propagation of electromagnetic wave in plasma by using the Boltzmann-Maxwell theory. In order to verify this theory, the whole process of electromagnetic wave propagating in plasma under one-dimension case is simulated. Results show that Boltzmann-Maxwell theory can be used to explain the phenomenon of electromagnetic wave propagating in plasma. Finally, the two-dimensional simulation model of plasma antenna is established under the cylindrical coordinate. And the near-field and far-field radiation pattern of plasma antenna are obtained. The experiments show that the variation of electron density can introduce the change of radiation characteristic.

Research on radiation characteristic of plasma antenna through FDTD method.

Science.gov (United States)

Zhou, Jianming; Fang, Jingjing; Lu, Qiuyuan; Liu, Fan

2014-01-01

The radiation characteristic of plasma antenna is investigated by using the finite-difference time-domain (FDTD) approach in this paper. Through using FDTD method, we study the propagation of electromagnetic wave in free space in stretched coordinate. And the iterative equations of Maxwell equation are derived. In order to validate the correctness of this method, we simulate the process of electromagnetic wave propagating in free space. Results show that electromagnetic wave spreads out around the signal source and can be absorbed by the perfectly matched layer (PML). Otherwise, we study the propagation of electromagnetic wave in plasma by using the Boltzmann-Maxwell theory. In order to verify this theory, the whole process of electromagnetic wave propagating in plasma under one-dimension case is simulated. Results show that Boltzmann-Maxwell theory can be used to explain the phenomenon of electromagnetic wave propagating in plasma. Finally, the two-dimensional simulation model of plasma antenna is established under the cylindrical coordinate. And the near-field and far-field radiation pattern of plasma antenna are obtained. The experiments show that the variation of electron density can introduce the change of radiation characteristic.

Singular characteristic tracking algorithm for improved solution accuracy of the discrete ordinates method with isotropic scattering

International Nuclear Information System (INIS)

Duo, J. I.; Azmy, Y. Y.

2007-01-01

A new method, the Singular Characteristics Tracking algorithm, is developed to account for potential non-smoothness across the singular characteristics in the exact solution of the discrete ordinates approximation of the transport equation. Numerical results show improved rate of convergence of the solution to the discrete ordinates equations in two spatial dimensions with isotropic scattering using the proposed methodology. Unlike the standard Weighted Diamond Difference methods, the new algorithm achieves local convergence in the case of discontinuous angular flux along the singular characteristics. The method also significantly reduces the error for problems where the angular flux presents discontinuous spatial derivatives across these lines. For purposes of verifying the results, the Method of Manufactured Solutions is used to generate analytical reference solutions that permit estimating the local error in the numerical solution. (authors)

An improved method for predicting the evolution of the characteristic parameters of an information system

Science.gov (United States)

Dushkin, A. V.; Kasatkina, T. I.; Novoseltsev, V. I.; Ivanov, S. V.

2018-03-01

The article proposes a forecasting method that allows, based on the given values of entropy and error level of the first and second kind, to determine the allowable time for forecasting the development of the characteristic parameters of a complex information system. The main feature of the method under consideration is the determination of changes in the characteristic parameters of the development of the information system in the form of the magnitude of the increment in the ratios of its entropy. When a predetermined value of the prediction error ratio is reached, that is, the entropy of the system, the characteristic parameters of the system and the depth of the prediction in time are estimated. The resulting values of the characteristics and will be optimal, since at that moment the system possessed the best ratio of entropy as a measure of the degree of organization and orderliness of the structure of the system. To construct a method for estimating the depth of prediction, it is expedient to use the maximum principle of the value of entropy.

Discontinuous finite element and characteristics methods for neutrons transport equation solution in heterogeneous grids

International Nuclear Information System (INIS)

Masiello, E.

2006-01-01

The principal goal of this manuscript is devoted to the investigation of a new type of heterogeneous mesh adapted to the shape of the fuel pins (fuel-clad-moderator). The new heterogeneous mesh guarantees the spatial modelling of the pin-cell with a minimum of regions. Two methods are investigated for the spatial discretization of the transport equation: the discontinuous finite element method and the method of characteristics for structured cells. These methods together with the new representation of the pin-cell result in an appreciable reduction of calculation points. They allow an exact modelling of the fuel pin-cell without spatial homogenization. A new synthetic acceleration technique based on an angular multigrid is also presented for the speed up of the inner iterations. These methods are good candidates for transport calculations for a nuclear reactor core. A second objective of this work is the application of method of characteristics for non-structured geometries to the study of double heterogeneity problem. The letters is characterized by fuel material with a stochastic dispersion of heterogeneous grains, and until now was solved with a model based on collision probabilities. We propose a new statistical model based on renewal-Markovian theory, which makes possible to take into account the stochastic nature of the problem and to avoid the approximations of the collision probability model. The numerical solution of this model is guaranteed by the method of characteristics. (author)

A Fast Optimization Method for Reliability and Performance of Cloud Services Composition Application

Directory of Open Access Journals (Sweden)

Zhao Wu

2013-01-01

Full Text Available At present the cloud computing is one of the newest trends of distributed computation, which is propelling another important revolution of software industry. The cloud services composition is one of the key techniques in software development. The optimization for reliability and performance of cloud services composition application, which is a typical stochastic optimization problem, is confronted with severe challenges due to its randomness and long transaction, as well as the characteristics of the cloud computing resources such as openness and dynamic. The traditional reliability and performance optimization techniques, for example, Markov model and state space analysis and so forth, have some defects such as being too time consuming and easy to cause state space explosion and unsatisfied the assumptions of component execution independence. To overcome these defects, we propose a fast optimization method for reliability and performance of cloud services composition application based on universal generating function and genetic algorithm in this paper. At first, a reliability and performance model for cloud service composition application based on the multiple state system theory is presented. Then the reliability and performance definition based on universal generating function is proposed. Based on this, a fast reliability and performance optimization algorithm is presented. In the end, the illustrative examples are given.

Performance characteristics of dedicated molecular breast imaging systems at low doses

Energy Technology Data Exchange (ETDEWEB)

Long, Zaiyang; Conners, Amy L.; Hunt, Katie N.; Hruska, Carrie B.; O’Connor, Michael K., E-mail: mkoconnor@mayo.edu [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)

2016-06-15

Purpose: The purpose of this study was to compare the system performance characteristics and lesion detection capability of two molecular breast imaging (MBI) systems: a multicrystal sodium iodide (NaI)-based single-head system and a cadmium zinc telluride (CZT)-based dual-head system at low administered doses (150–300 MBq) of Tc-99m sestamibi. Methods: System performance characteristics including count sensitivity, uniformity, energy resolution, and spatial resolution were measured using standard NEMA methods, or a modified version thereof in cases where the standard NEMA protocol could not be applied. A contrast-detail phantom with 48 lesions at varying depths from the collimator surface was used to assess lesion contrast-to-noise-ratio (CNR) using background count densities comparable to those observed in patient studies performed with administered doses of 150 MBq Tc-99m sestamibi. Lesions with CNR >3 were deemed to be detectable. Thirty patients undergoing MBI examinations with administered doses of 150–300 MBq were scanned for an additional view on the pixelated NaI system. CNR was calculated for lesions observed on patient images. Background count densities of patient images were measured and compared between the two systems. Results: Over the central field of view, integral and differential uniformity were 6.1% and 4.2%, respectively, for the pixelated NaI system, and 3.8% and 2.7%, respectively, for the CZT system. Count sensitivity was 10.8 kcts/min/MBq for the NaI system and 32.9 kcts/min/MBq for the CZT system. Energy resolution was 13.5% on the pixelated NaI system and 4.5% on the CZT system. Spatial resolution (full-width at half-maximum) for the pixelated NaI detector was 4.2 mm at a distance of 1.2 cm from the collimator and 5.2 mm at 3.1 cm. Spatial resolution of a single CZT detector was 2.9 mm at a distance of 1.2 cm from the collimator and 4.7 mm at 3.1 cm. Effective spatial resolution obtained with dual-head CZT was below 4.7 mm throughout

On the use of LDA performance as a metric of feature extraction methods for a P300 BCI classification task

International Nuclear Information System (INIS)

Gareis, Iván; Atum, Yanina; Gentiletti, Gerardo; Acevedo, Rubén; Bañuelos, Verónica Medina; Rufiner, Leonardo

2011-01-01

Brain computer interfaces (BCIs) translate brain activity into computer commands. To enhance the performance of a BCI, it is necessary to improve the feature extraction techniques being applied to decode the users' intentions. Objective comparison methods are needed to analyze different feature extraction techniques. One possibility is to use the classifier performance as a comparative measure. In this work the effect of several variables that affect the behaviour of linear discriminant analysis (LDA) has been studied when used to distinguish between electroencephalographic signals with and without the presence of event related potentials (ERPs). The error rate (ER) and the area under the receiver operating characteristic curve (AUC) were used as performance estimators of LDA. The results show that the number of characteristics, the degree of balance of the training patterns set and the number of averaged trials affect the classifier's performance and therefore, must be considered in the design of the integrated system.

Experimental study for flow characteristics and performance evaluation of butterfly valves

International Nuclear Information System (INIS)

Kim, C K; Shin, M S; Yoon, J Y

2010-01-01

The industrial butterfly valves have been applied to transport a large of fluid with various fields of industry. Also, these are mainly used a control of fluid flux to the water and waste-water pipeline. Present, butterfly valves are manufacturing for multiplicity shape of bodies and discs with many producers. However, appropriate performance evaluation was not yet accomplished to compare about these valves through experiments. This study is performed the experiment of flow characteristics and performance of manufactured 400A butterfly valves for the water and waste pipeline, and compared experimental results. We performed experiments that were controlled fixed a differential pressure condition (1 psi) and the range of the flow rate conditions (500 m 3 /hr ∼ 2500 m 3 /hr), and also opened the disc of valves to a range of angle from 9 degree to 90 degree. We investigated and compared the valve flow coefficient and the valve loss coefficient of results through experiments with each butterfly valve.

Characteristics of shift work and their impact on employee performance and wellbeing: A literature review.

Science.gov (United States)

Dall'Ora, Chiara; Ball, Jane; Recio-Saucedo, Alejandra; Griffiths, Peter

2016-05-01

To identify the characteristics of shift work that have an effect on employee's performance (including job performance, productivity, safety, quality of care delivered, errors, adverse events and client satisfaction) and wellbeing (including burnout, job satisfaction, absenteeism, intention to leave the job) in all sectors including healthcare. A scoping review of the literature was undertaken. We searched electronic databases (CINAHL, MEDLINE, PsychINFO, SCOPUS) to identify primary quantitative studies. The search was conducted between January and March 2015. Studies were drawn from all occupational sectors (i.e. health and non health), meeting the inclusion criteria: involved participants aged ≥18 who have been working shifts or serve as control group for others working shifts, exploring the association of characteristics of shift work with at least one of the selected outcomes. Reference lists from retrieved studies were checked to identify any further studies. 35 studies were included in the review; 25 studies were performed in the health sector. A variety of shift work characteristics are associated with compromised employee's performance and wellbeing. Findings from large multicentre studies highlight that shifts of 12h or longer are associated with jeopardised outcomes. Working more than 40h per week is associated with adverse events, while no conclusive evidence was found regarding working a 'Compressed Working Week'; working overtime was associated with decreased job performance. Working rotating shifts was associated with worse job performance outcomes, whilst fixed night shifts appeared to enable resynchronisation. However, job satisfaction of employees working fixed nights was reduced. Timely breaks had a positive impact on employee fatigue and alertness, whilst quick returns between shifts appeared to increase pathologic fatigue. The effect of shift work characteristics on outcomes in the studies reviewed is consistent across occupational sectors

Application of Monte Carlo method in determination of secondary characteristic X radiation in XFA

International Nuclear Information System (INIS)

Roubicek, P.

1982-01-01

Secondary characteristic radiation is excited by primary radiation from the X-ray tube and by secondary radiation of other elements so that excitations of several orders result. The Monte Carlo method was used to consider all these possibilities and the resulting flux of characteristic radiation was simulated for samples of silicate raw materials. A comparison of the results of these computations with experiments allows to determine the effect of sample preparation on the characteristic radiation flux. (M.D.)

Performance characteristics of single effect lithium bromide/ water absorption chiller for small data centers

Science.gov (United States)

Mysore, Abhishek Arun Babu

A medium data center consists of servers performing operations such as file sharing, collaboration and email. There are a large number of small and medium data centers across the world which consume more energy and are less efficient when compared to large data center facilities of companies such as GOOGLE, APPLE and FACEBOOK. Such companies are making their data center facilities more environmental friendly by employing renewable energy solutions such as wind and solar to power the data center or in data center cooling. This not only reduces the carbon footprint significantly but also decreases the costs incurred over a period of time. Cooling of data center play a vital role in proper functioning of the servers. It is found that cooling consumes about 50% of the total power consumed by the data center. Traditional method of cooling includes the use of mechanical compression chillers which consume lot of power and is not desirable. In order to eliminate the use of mechanical compressor chillers renewable energy resources such as solar and wind should be employed. One such technology is solar thermal cooling by means of absorption chiller which is powered by solar energy. The absorption chiller unit can be coupled with either flat plate or evacuated tube collectors in order to achieve the required inlet temperature for the generator of the absorption chiller unit. In this study a modular data center is considered having a cooling load requirement of 23kw. The performance characteristics of a single stage Lithium Bromide/ water refrigeration is presented in this study considering the cooling load of 23kw. Performance characteristics of each of the 4 heat exchangers within the unit is discussed which helps in customizing the unit according to the users' specific needs. This analysis helps in studying the importance of different properties such as the effect of inlet temperatures of hot water for generator, inlet temperatures of cooling water for absorber and

Organizational characteristics, financial performance measures, and funding sources of faith based organizations.

Science.gov (United States)

Lampkin, Lynne; Raghavan, Kamala

2008-01-01

This study examined the impact of organizational characteristics and financial performance measures of faith based organizations (FBOS) in Pennsylvania and Ohio on the decisions of the funding sources. Organizational characteristics of size, age, and type of service, and financial performance measures such as expense, liquidity, and solvency ratios were gathered from the data on IRS form 990 for 97 FBOS for the period of 1995 to 2004. The study found that the 1996 Charitable Choice provisions and the 2001 Office of Faith-Based and Community Initiatives have led to increased government funding for FBOS. The results showed that government funding of FBOS is affected positively by age of the FBO, and negatively by its size. For smaller FBOS, savings ratio had a negative relationship to government funding and a positive relationship to direct public support. For social service FBOS government funding was positively affected by age and negatively affected by size and debt ratio, while days-cash-on-hand had a negative impact on direct public support. All of the above relationships were statistically significant.

Systems, methods and computer-readable media for modeling cell performance fade of rechargeable electrochemical devices

Science.gov (United States)

Gering, Kevin L

2013-08-27

A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware periodically samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics of the electrochemical cell. The computing system also develops a mechanistic level model of the electrochemical cell to determine performance fade characteristics of the electrochemical cell and analyzing the mechanistic level model to estimate performance fade characteristics over aging of a similar electrochemical cell. The mechanistic level model uses first constant-current pulses applied to the electrochemical cell at a first aging period and at three or more current values bracketing a first exchange current density. The mechanistic level model also is based on second constant-current pulses applied to the electrochemical cell at a second aging period and at three or more current values bracketing the second exchange current density.

Application of the DSA preconditioned GMRES formalism to the method of characteristics - First results

International Nuclear Information System (INIS)

Le Tellier, R.; Hebert, A.

2004-01-01

The method of characteristics is well known for its slow convergence; consequently, as it is often done for SN methods, the Generalized Minimal Residual approach (GMRES) has been investigated for its practical implementation and its high reliability. GMRES is one of the most effective Krylov iterative methods to solve large linear systems. Moreover, the system has been 'left preconditioned' with the Algebraic Collapsing Acceleration (ACA) a variant of the Diffusion Synthetic Acceleration (DSA) based on I. Suslov's former works. This paper presents the first numerical results of these methods in 2D geometries with material discontinuities. Indeed, previous investigations have shown a degraded effectiveness of Diffusion Synthetic Accelerations with this kind of geometries. Results are presented for 9 x 9 Cartesian assemblies in terms of the speed of convergence of the inner iterations (fixed source) of the method of characteristics. It shows a significant improvement on the convergence rate. (authors)

Systems, methods and computer-readable media to model kinetic performance of rechargeable electrochemical devices

Science.gov (United States)

Gering, Kevin L.

2013-01-01

A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics. The computing system also analyzes the cell information of the electrochemical cell with a Butler-Volmer (BV) expression modified to determine exchange current density of the electrochemical cell by including kinetic performance information related to pulse-time dependence, electrode surface availability, or a combination thereof. A set of sigmoid-based expressions may be included with the modified-BV expression to determine kinetic performance as a function of pulse time. The determined exchange current density may be used with the modified-BV expression, with or without the sigmoid expressions, to analyze other characteristics of the electrochemical cell. Model parameters can be defined in terms of cell aging, making the overall kinetics model amenable to predictive estimates of cell kinetic performance along the aging timeline.

Comparing the performance of biomedical clustering methods

DEFF Research Database (Denmark)

Wiwie, Christian; Baumbach, Jan; Röttger, Richard

2015-01-01

expression to protein domains. Performance was judged on the basis of 13 common cluster validity indices. We developed a clustering analysis platform, ClustEval (http://clusteval.mpi-inf.mpg.de), to promote streamlined evaluation, comparison and reproducibility of clustering results in the future......Identifying groups of similar objects is a popular first step in biomedical data analysis, but it is error-prone and impossible to perform manually. Many computational methods have been developed to tackle this problem. Here we assessed 13 well-known methods using 24 data sets ranging from gene....... This allowed us to objectively evaluate the performance of all tools on all data sets with up to 1,000 different parameter sets each, resulting in a total of more than 4 million calculated cluster validity indices. We observed that there was no universal best performer, but on the basis of this wide...

Characteristic performance evaluation of a photon counting Si strip detector for low dose spectral breast CT imaging

Science.gov (United States)

Cho, Hyo-Min; Barber, William C.; Ding, Huanjun; Iwanczyk, Jan S.; Molloi, Sabee

2014-01-01

Purpose: The possible clinical applications which can be performed using a newly developed detector depend on the detector's characteristic performance in a number of metrics including the dynamic range, resolution, uniformity, and stability. The authors have evaluated a prototype energy resolved fast photon counting x-ray detector based on a silicon (Si) strip sensor used in an edge-on geometry with an application specific integrated circuit to record the number of x-rays and their energies at high flux and fast frame rates. The investigated detector was integrated with a dedicated breast spectral computed tomography (CT) system to make use of the detector's high spatial and energy resolution and low noise performance under conditions suitable for clinical breast imaging. The aim of this article is to investigate the intrinsic characteristics of the detector, in terms of maximum output count rate, spatial and energy resolution, and noise performance of the imaging system. Methods: The maximum output count rate was obtained with a 50 W x-ray tube with a maximum continuous output of 50 kVp at 1.0 mA. A109Cd source, with a characteristic x-ray peak at 22 keV from Ag, was used to measure the energy resolution of the detector. The axial plane modulation transfer function (MTF) was measured using a 67 μm diameter tungsten wire. The two-dimensional (2D) noise power spectrum (NPS) was measured using flat field images and noise equivalent quanta (NEQ) were calculated using the MTF and NPS results. The image quality parameters were studied as a function of various radiation doses and reconstruction filters. The one-dimensional (1D) NPS was used to investigate the effect of electronic noise elimination by varying the minimum energy threshold. Results: A maximum output count rate of 100 million counts per second per square millimeter (cps/mm2) has been obtained (1 million cps per 100 × 100 μm pixel). The electrical noise floor was less than 4 keV. The energy resolution

Parallel 3-D method of characteristics in MPACT

International Nuclear Information System (INIS)

Kochunas, B.; Dovvnar, T. J.; Liu, Z.

2013-01-01

A new parallel 3-D MOC kernel has been developed and implemented in MPACT which makes use of the modular ray tracing technique to reduce computational requirements and to facilitate parallel decomposition. The parallel model makes use of both distributed and shared memory parallelism which are implemented with the MPI and OpenMP standards, respectively. The kernel is capable of parallel decomposition of problems in space, angle, and by characteristic rays up to 0(104) processors. Initial verification of the parallel 3-D MOC kernel was performed using the Takeda 3-D transport benchmark problems. The eigenvalues computed by MPACT are within the statistical uncertainty of the benchmark reference and agree well with the averages of other participants. The MPACT k eff differs from the benchmark results for rodded and un-rodded cases by 11 and -40 pcm, respectively. The calculations were performed for various numbers of processors and parallel decompositions up to 15625 processors; all producing the same result at convergence. The parallel efficiency of the worst case was 60%, while very good efficiency (>95%) was observed for cases using 500 processors. The overall run time for the 500 processor case was 231 seconds and 19 seconds for the case with 15625 processors. Ongoing work is focused on developing theoretical performance models and the implementation of acceleration techniques to minimize the number of iterations to converge. (authors)

Analytic Method on Characteristic Parameters of Bacteria in Water by Multiwavelength Transmission Spectroscopy

Directory of Open Access Journals (Sweden)

Yuxia Hu

2017-01-01

Full Text Available An analytic method together with the Mie scattering theory and Beer-Lambert law is proposed for the characteristic parameter determination of bacterial cells (Escherichia coli 10389 from multiwavelength transmission spectroscopy measurements. We calculate the structural parameters of E. coli cells, and compared with the microscopy, the relative error of cell volume is 7.90%, the cell number is compared with those obtained by plate counting, the relative error is l.02%, and the nucleic content and protein content of single E. coli cells are consistent with the data reported elsewhere. The proposed method can obtain characteristic parameters of bacteria as an excellent candidate for the rapid detection and identification of bacteria in the water.

Effect of Exhaust Gas Recirculation (EGR) on the Performance Characteristics of a Direct Injection Multi Cylinders Diesel Engine

OpenAIRE

Khalil Ibrahim Abaas

2016-01-01

Owing  to  the  energy  crisis  and  pollution  problems  of  today  investigations  have  concentrated  on decreasing  fuel  consumption  and  on  lowering  the  concentration  of  toxic  components  in  combustion products by using exhaust gas after treatments methods like PM filters and EGR for NOx reduction. In this study, the combustion characteristics of diesel fuel were compared with that pr oduced from adding EGR at several percentages to air manifold. The tests were performed in a fo...

A location-based multiple point statistics method: modelling the reservoir with non-stationary characteristics

Directory of Open Access Journals (Sweden)

Yin Yanshu

2017-12-01

Full Text Available In this paper, a location-based multiple point statistics method is developed to model a non-stationary reservoir. The proposed method characterizes the relationship between the sedimentary pattern and the deposit location using the relative central position distance function, which alleviates the requirement that the training image and the simulated grids have the same dimension. The weights in every direction of the distance function can be changed to characterize the reservoir heterogeneity in various directions. The local integral replacements of data events, structured random path, distance tolerance and multi-grid strategy are applied to reproduce the sedimentary patterns and obtain a more realistic result. This method is compared with the traditional Snesim method using a synthesized 3-D training image of Poyang Lake and a reservoir model of Shengli Oilfield in China. The results indicate that the new method can reproduce the non-stationary characteristics better than the traditional method and is more suitable for simulation of delta-front deposits. These results show that the new method is a powerful tool for modelling a reservoir with non-stationary characteristics.

Teacher characteristics and student performance: An analysis using hierarchical linear modelling

Directory of Open Access Journals (Sweden)

Paula Armstrong

2015-12-01

Full Text Available This research makes use of hierarchical linear modelling to investigate which teacher characteristics are significantly associated with student performance. Using data from the SACMEQ III study of 2007, an interesting and potentially important finding is that younger teachers are better able to improve the mean mathematics performance of their students. Furthermore, younger teachers themselves perform better on subject tests than do their older counterparts. Identical models are run for Sub Saharan countries bordering on South Africa, as well for Kenya and the strong relationship between teacher age and student performance is not observed. Similarly, the model is run for South Africa using data from SACMEQ II (conducted in 2002 and the relationship between teacher age and student performance is also not observed. It must be noted that South African teachers were not tested in SACMEQ II so it was not possible to observe differences in subject knowledge amongst teachers in different cohorts and it was not possible to control for teachers’ level of subject knowledge when observing the relationship between teacher age and student performance. Changes in teacher education in the late 1990s and early 2000s may explain the differences in the performance of younger teachers relative to their older counterparts observed in the later dataset.

Generic anthropometric and performance characteristics among elite adolescent boys in nine different sports.

Science.gov (United States)

Pion, Johan; Segers, Veerle; Fransen, Job; Debuyck, Gijs; Deprez, Dieter; Haerens, Leen; Vaeyens, Roel; Philippaerts, Renaat; Lenoir, Matthieu

2015-01-01

The aim of the present study was to evaluate the Flemish Sports Compass (FSC), a non-sport-specific generic testing battery. It was hypothesised that a set of 22 tests would have sufficient discriminant power to allocate athletes to their own sport based on a unique combination of test scores. First, discriminant analyses were applied to the 22 tests of anthropometry, physical fitness and motor coordination in 141 boys under age 18 (16.1 ± 0.8 years) and post age at peak height velocity (maturity offset = 2.674 ± 0.926) from Flemish Top Sport Academies for badminton, basketball, gymnastics, handball, judo, soccer, table tennis, triathlon and volleyball. Second, nine sequential discriminant analyses were used to assess the ability of a set of relevant performance characteristics classifying participants and non-participants for the respective sports. Discriminant analyses resulted in a 96.4% correct classification of all participants for the nine different sports. When focusing on relevant performance characteristics, 80.1% to 97.2% of the total test sample was classified correctly within their respective disciplines. The discriminating characteristics were briefly the following: flexibility in gymnastics, explosive lower-limb strength in badminton and volleyball, speed and agility in badminton, judo, soccer and volleyball, upper-body strength in badminton, basketball and gymnastics, cardiorespiratory endurance in triathletes, dribbling skills in handball, basketball and soccer and overhead-throwing skills in badminton and volleyball. The generic talent characteristics of the FSC enable the distinction of adolescent boys according to their particular sport. Implications for talent programmes are discussed.

Performance and flow characteristics of MHD seawater thruster

Energy Technology Data Exchange (ETDEWEB)

Doss, E.D.

1990-01-01

The main goal of the research is to investigate the effects of strong magnetic fields on the electrical and flow fields inside MHD thrusters. The results of this study is important in the assessment of the feasibility of MHD seawater propulsion for the Navy. To accomplish this goal a three-dimensional fluid flow computer model has been developed and applied to study the concept of MHD seawater propulsion. The effects of strong magnetic fields on the current and electric fields inside the MHD thruster and their interaction with the flow fields, particularly those in the boundary layers, have been investigated. The results of the three-dimensional computations indicate that the velocity profiles are flatter over the sidewalls of the thruster walls in comparison to the velocity profiles over the electrode walls. These nonuniformities in the flow fields give rise to nonuniform distribution of the skin friction along the walls of the thrusters, where higher values are predicted over the sidewalls relative to those over the electrode walls. Also, a parametric study has been performed using the three-dimensional MHD flow model to analyze the performance of continuous electrode seawater thrusters under different operating parameters. The effects of these parameters on the fluid flow characteristics, and on the thruster efficiency have been investigated. Those parameters include the magnetic field (10--20 T), thruster diameter, surface roughness, flow velocity, and the electric load factor. The results show also that the thruster performance improves with the strength of the magnetic field and thruster diameter, and the efficiency decreases with the flow velocity and surface roughness.

SELECTION OF ENDOCRINOLOGY SUBSPECIALTY TRAINEES: WHICH APPLICANT CHARACTERISTICS ARE ASSOCIATED WITH PERFORMANCE DURING FELLOWSHIP TRAINING?

Science.gov (United States)

Natt, Neena; Chang, Alice Y; Berbari, Elie F; Kennel, Kurt A; Kearns, Ann E

2016-01-01

To determine which residency characteristics are associated with performance during endocrinology fellowship training as measured by competency-based faculty evaluation scores and faculty global ratings of trainee performance. We performed a retrospective review of interview applications from endocrinology fellows who graduated from a single academic institution between 2006 and 2013. Performance measures included competency-based faculty evaluation scores and faculty global ratings. The association between applicant characteristics and measures of performance during fellowship was examined by linear regression. The presence of a laudatory comparative statement in the residency program director's letter of recommendation (LoR) or experience as a chief resident was significantly associated with competency-based faculty evaluation scores (β = 0.22, P = .001; and β = 0.24, P = .009, respectively) and faculty global ratings (β = 0.85, P = .006; and β = 0.96, P = .015, respectively). The presence of a laudatory comparative statement in the residency program director's LoR or experience as a chief resident were significantly associated with overall performance during subspecialty fellowship training. Future studies are needed in other cohorts to determine the broader implications of these findings in the application and selection process.

A method to enhance the curve negotiation performance of HTS Maglev

Science.gov (United States)

Che, T.; Gou, Y. F.; Deng, Z. G.; Zheng, J.; Zheng, B. T.; Chen, P.

2015-09-01

High temperature superconducting (HTS) Maglev has attracted more and more attention due to its special self-stable characteristic, and much work has been done to achieve its actual application, but the research about the curve negotiation is not systematic and comprehensive. In this paper, we focused on the change of the lateral displacements of the Maglev vehicle when going through curves under different velocities, and studied the change of the electromagnetic forces through experimental methods. Experimental results show that setting an appropriate initial eccentric distance (ED), which is the distance between the center of the bulk unit and the center of the permanent magnet guideway (PMG), when cooling the bulks is favorable for the Maglev system’s curve negotiation. This work will provide some available suggestions for improving the curve negotiation performance of the HTS Maglev system.

Comprehensive Deployment Method for Technical Characteristics Base on Multi-failure Modes Correlation Analysis

Science.gov (United States)

Zheng, W.; Gao, J. M.; Wang, R. X.; Chen, K.; Jiang, Y.

2017-12-01

This paper put forward a new method of technical characteristics deployment based on Reliability Function Deployment (RFD) by analysing the advantages and shortages of related research works on mechanical reliability design. The matrix decomposition structure of RFD was used to describe the correlative relation between failure mechanisms, soft failures and hard failures. By considering the correlation of multiple failure modes, the reliability loss of one failure mode to the whole part was defined, and a calculation and analysis model for reliability loss was presented. According to the reliability loss, the reliability index value of the whole part was allocated to each failure mode. On the basis of the deployment of reliability index value, the inverse reliability method was employed to acquire the values of technology characteristics. The feasibility and validity of proposed method were illustrated by a development case of machining centre’s transmission system.

Mammography in Norway: Image quality and total performance

International Nuclear Information System (INIS)

Olsen, J.B.; Skretting, A.; Widmark, A.

1997-04-01

This report describes a method for assessing the total performance in mammography based on Receiver Operating Characteristic (ROC) analysis. In the time period from December 1993 to March 1994 the method was applied to assess the total performance of all the 45 Norwegian mammography laboratories operative at that time. Image quality characteristics in each laboratory was established by use of well-known phantoms

A method for optimizing the performance of buildings

Energy Technology Data Exchange (ETDEWEB)

Pedersen, Frank

2006-07-01

This thesis describes a method for optimizing the performance of buildings. Design decisions made in early stages of the building design process have a significant impact on the performance of buildings, for instance, the performance with respect to the energy consumption, economical aspects, and the indoor environment. The method is intended for supporting design decisions for buildings, by combining methods for calculating the performance of buildings with numerical optimization methods. The method is able to find optimum values of decision variables representing different features of the building, such as its shape, the amount and type of windows used, and the amount of insulation used in the building envelope. The parties who influence design decisions for buildings, such as building owners, building users, architects, consulting engineers, contractors, etc., often have different and to some extent conflicting requirements to buildings. For instance, the building owner may be more concerned about the cost of constructing the building, rather than the quality of the indoor climate, which is more likely to be a concern of the building user. In order to support the different types of requirements made by decision-makers for buildings, an optimization problem is formulated, intended for representing a wide range of design decision problems for buildings. The problem formulation involves so-called performance measures, which can be calculated with simulation software for buildings. For instance, the annual amount of energy required by the building, the cost of constructing the building, and the annual number of hours where overheating occurs, can be used as performance measures. The optimization problem enables the decision-makers to specify many different requirements to the decision variables, as well as to the performance of the building. Performance measures can for instance be required to assume their minimum or maximum value, they can be subjected to upper or

Characteristics of medical teachers using student-centered teaching methods.

Science.gov (United States)

Kim, Kyong-Jee; Hwang, Jee-Young

2017-09-01

This study investigated characteristics of medical teachers who have adopted student-centered teaching methods into their teaching. A 24-item questionnaire consisted of respondent backgrounds, his or her use of student-centered teaching methods, and awareness of the school's educational objectives and curricular principles was administered of faculty members at a private medical school in Korea. Descriptive statistics and chi-square analysis were conducted to compare faculty use of student-centered approaches across different backgrounds and awareness of curricular principles. Overall response rate was 70% (N=140/200), approximately 25% (n=34) of whom were using student-centered teaching methods. Distributions in the faculty use of student-centered teaching methods were significantly higher among basic sciences faculty (versus clinical sciences faculty), with teaching experiences of over 10 years (versus less than 10 years), and who were aware of the school's educational objectives and curricular principles. Our study indicates differences in medical faculty's practice of student-centered teaching across disciplines, teaching experiences, and their understanding of the school's educational objectives curricular principles. These findings have implications for faculty development and institutional support to better promote faculty use of student-centered teaching approaches.

Cathodoluminescence characteristics of polycrystalline diamond films grown by cyclic deposition method

International Nuclear Information System (INIS)

Seo, Soo-Hyung; Park, Chang-Kyun; Park, Jin-Seok

2002-01-01

Polycrystalline diamond films were deposited using a cyclic deposition method where the H 2 plasma for etching (t E ) and the CH 4 +H 2 plasma for growing (t G ) are alternately modulated with various modulation ratios (t E /t G ). From the measurement of full width at half maximum and I D /I G intensity ratio obtained from the Raman spectra, it was found that diamond defects and non-diamond carbon phases were reduced a little by adopting the cyclic deposition method. From the cathodoluminescence (CL) characteristics measured for deposited films, the nitrogen-related band (centered at approximately 590 nm) as well as the so-called band-A (centered at approximately 430 nm) were observed. As the cyclic ratio t E /t G increased, the relative intensity ratio of band-A to nitrogen-related band (I A /I N ) was found to monotonically decrease. In addition, analysis of X-ray diffraction spectra and scanning electron microscope morphologies showed that CL characteristics of deposited diamond films were closely related to their crystal orientations and morphologies

The Relationship between Anthropometric Characteristics and Crawl and Breaststroke Performance in Adolescent Girl Swimmers

Directory of Open Access Journals (Sweden)

Shirin Yazdani

2017-03-01

Full Text Available Objective: The aim of this study was to investigate the relationship between anthropometric characteristics and crawl and breaststroke performance in adolescent girl swimmers with an emphasis on ratio of length and width of limbs to the height of subjects. Methods: Twenty adolescent female swimmers voluntarily participated in this study. Anthropometric variables, including height , length of thigh, leg, foot, arm, forearm and hand , arm span, widths of pelvic, shoulders, knees, wrists and ankles were measured using a tape measure and caliper. Then the ratio of length and width of limbs to the height of subjects was calculated. Pearson correlation test at a significance level of 0.05 was used for statistical analysis. Results: Significant relationship were found between crawl record and subjects’ height, thigh, arm and forearm lengths, arm span, shoulder width, the ratios of arm, palm and foot length to the height and ratio of arm span to height (p<0.05. Also, the relationship between breaststroke record and subjects’ height, arm and thigh lengths, arm span, shoulder and palm widths, the ratios of forearm and thigh lengths to the height, ratio of shoulder girdle width to height and ratio of shoulder girdle to pelvic width were all found to be significant (p<0.05. Conclusion: In addition to the effect of anthropometric characteristics such as height, arm, forearm, thigh lengths, arm span, palm and shoulder girdle widths on the performance of adolescent girl swimmers, the ratios of limb lengths and widths to the height and ratio of shoulder girdle to pelvic width were positively related with swimming record. Thus, it is recommended that to achieve better results in swimming talent, coaches consider the ratio of limbs to the height.

Realization of method of characteristics based on customization of AutoCAD

International Nuclear Information System (INIS)

Chen Qichang; Wu Hongchun; Cao Liangzhi

2009-01-01

The method of characteristics (MOC) solves the neutron transport equation along each characteristics line. Theoretically, it is independent of the geometry shape of boundary and region. However, the geometry should be described, and ray tracing should be carried out firstly. In most of the existing MOC codes, the geometry description and ray tracing still have more or less limitation. To wipe off these geometry limitations for using MOC in more complex fuel assembly calculation, a new MOC code AutoMOC based on the customization of AutoCAD was developed. The numerical results show that AutoMOC not only has high flexibility in geometry but also gives accurate solutions in comparison with state-of-the-art methodologies. (authors)

Study on method of characteristics based on cell modular ray tracing

International Nuclear Information System (INIS)

Tang Chuntao; Zhang Shaohong

2009-01-01

To address the issue of accurately solving neutron transport problem in complex geometry, method of characteristics (MOC) is studied in this paper, and a quite effective and memory saving cell modular ray tracing (CMRT) method is developed and related angle discretization and boundary condition handling issues are discussed. A CMRT based MOC code-PEACH is developed and tested against C5G7 MOX benchmark problem. Numerical results demonstrate that PEACH can give excellent accuracy for both k eff and pin power distribution for neutron transport problem. (authors)

Statistical learning methods: Basics, control and performance

Energy Technology Data Exchange (ETDEWEB)

Zimmermann, J. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, 80805 Munich (Germany)]. E-mail: zimmerm@mppmu.mpg.de

2006-04-01

The basics of statistical learning are reviewed with a special emphasis on general principles and problems for all different types of learning methods. Different aspects of controlling these methods in a physically adequate way will be discussed. All principles and guidelines will be exercised on examples for statistical learning methods in high energy and astrophysics. These examples prove in addition that statistical learning methods very often lead to a remarkable performance gain compared to the competing classical algorithms.

Statistical learning methods: Basics, control and performance

International Nuclear Information System (INIS)

Zimmermann, J.

2006-01-01

The basics of statistical learning are reviewed with a special emphasis on general principles and problems for all different types of learning methods. Different aspects of controlling these methods in a physically adequate way will be discussed. All principles and guidelines will be exercised on examples for statistical learning methods in high energy and astrophysics. These examples prove in addition that statistical learning methods very often lead to a remarkable performance gain compared to the competing classical algorithms

Gradient High Performance Liquid Chromatography Method ...

African Journals Online (AJOL)

Purpose: To develop a gradient high performance liquid chromatography (HPLC) method for the simultaneous determination of phenylephrine (PHE) and ibuprofen (IBU) in solid ..... nimesulide, phenylephrine. Hydrochloride, chlorpheniramine maleate and caffeine anhydrous in pharmaceutical dosage form. Acta Pol.

Firm performance: The role of CEOs' emotional and cognitive characteristics

Directory of Open Access Journals (Sweden)

Kleanthis K. Katsaros

2015-08-01

Full Text Available The paper examines the relationships between CEOs’ personal traits, emotions, attitudes and tolerance of ambiguity; and subsequently, the influence of CEOs’ ambiguity tolerance in firms' performance. Design/methodology/approach – Survey data were collected from 256 ICT firms established in Greece. Their CEOs completed questionnaires examining TOA, personal traits, emotions and attitudes in the workplace. Principal components analysis and ordinary least-squares regressions were used to explore the hypotheses of the paper. Findings – Three factors characterize CEOs' emotions, namely pleasure, dominance and arousal; two factors their involvement, namely importance and interest; and, respectively, one their emotional intelligence namely, empathy/handling relationships. Further, locus of control; importance; arousal; empathy/handling relationships and interest affect decisively CEOs' tolerance of ambiguity, which in turn, seems to influence positively firms' performance. Research limitations/implications – Further research is required in Greek ICT industry regarding the influence of CEOs' emotional and cognitive attributes in organizations' financial performance. Likewise, this research should be expanded to other industries. Originality/value – The originality of this study lies in the finding that emotional and cognitive characteristics affect CEOs' TOA, which, in turn, influences significantly firms' performance. Another significant contributing factor is that the study is carried out in Greece, where few studies have been conducted in this area.

Progress in the study of PCHE performance with various stacking methods; PCHEs and test facility

International Nuclear Information System (INIS)

Kim, Ji Eun; Kim, Eun Ho; Yoon, Sung Ho; Kim, Moo Hwan; Park, Gun Yeop

2012-01-01

Printed Circuit Heat Exchanger (PCHE) is famous with its superior compactness and relatively higher resistance to pressure which came from its manufacturing process. PCHE is made by diffusion bonding of thin metal plates having various flow channel shapes on them. Diffusion bonding makes stack of plates become a monolithic block by grain growth between the surfaces of each plates near the melting temperature of material. With these characteristics, it has become a promising heat exchanger type in oil and gas industry, power plant and chemical reactors fields, despite of its relatively short history than others. From many researches, it is known that the flow channel and the stacking method of plates are the major design factors of PCHE. Flow channels have been studied by relatively many researchers, and there are several well known channel types like zigzag channel, S shape fin, and airfoil fin shape. On the other hands, there is little research about stacking method so called 'bank type'. By Kim et al., it was showed that stacking method of PCHE influences the heat transfer rate and pressure drop, but the comparison of the different stacking method was not conducted. In this research, heat transfer and pressure drop characteristics of PCHEs with various bank types will be studied. And this article will introduce three kinds of PCHEs fabricated by different bank types, and the test facility for performance test of these heat exchangers

Parametric methods of describing and extrapolating the characteristics of long-term strength of refractory materials

International Nuclear Information System (INIS)

Tsvilyuk, I.S.; Avramenko, D.S.

1986-01-01

This paper carries out the comparative analysis of the suitability of parametric methods for describing and extrapolating the results of longterm tests on refractory materials. Diagrams are presented of the longterm strength of niobium based alloys tested in a vacuum of 1.3 X 10 -3 Pa. The predicted values and variance of the estimate of endurance of refractory alloys are presented by parametric dependences. The longterm strength characteristics can be described most adequately by the Manson-Sakkop and Sherby-Dorn methods. Several methods must be used to ensure the reliable extrapolation of the longterm strength characteristics to the time period an order of magnitude longer than the experimental data. The most suitable method cannot always be selected on the basis of the correlation ratio

Understanding Team Communication Characteristics using Social Network Analysis

International Nuclear Information System (INIS)

Kim, Ar Ryum; Lee, Seung Woo; Seong, Poong Hyun; Park, Jin Kyun

2011-01-01

An important aspect of human behavior in nuclear power plants (NPPs) is team interaction since operating NPPs involves the coordination of several team members among and within workplaces. Since operators in main control room (MCR) get a great deal of information through communication to perform a task, communication is one of the important characteristics for team characteristics. Many researchers have been studying how to understand the characteristics of communication. Social network analysis (SNA) which is considered as an objective and easily applicable method has been already applied in many fields to investigate characteristics of team communication. Henttonen (2010) has struggled to perform the research on the impact of social networks in a team and he found some team communication characteristics could be obtained using some properties of SNA. In this paper, SNA is used to understand communication characteristics within operators in NPPs

BICEPP: an example-based statistical text mining method for predicting the binary characteristics of drugs

Directory of Open Access Journals (Sweden)

Tsafnat Guy

2011-04-01

Full Text Available Abstract Background The identification of drug characteristics is a clinically important task, but it requires much expert knowledge and consumes substantial resources. We have developed a statistical text-mining approach (BInary Characteristics Extractor and biomedical Properties Predictor: BICEPP to help experts screen drugs that may have important clinical characteristics of interest. Results BICEPP first retrieves MEDLINE abstracts containing drug names, then selects tokens that best predict the list of drugs which represents the characteristic of interest. Machine learning is then used to classify drugs using a document frequency-based measure. Evaluation experiments were performed to validate BICEPP's performance on 484 characteristics of 857 drugs, identified from the Australian Medicines Handbook (AMH and the PharmacoKinetic Interaction Screening (PKIS database. Stratified cross-validations revealed that BICEPP was able to classify drugs into all 20 major therapeutic classes (100% and 157 (of 197 minor drug classes (80% with areas under the receiver operating characteristic curve (AUC > 0.80. Similarly, AUC > 0.80 could be obtained in the classification of 173 (of 238 adverse events (73%, up to 12 (of 15 groups of clinically significant cytochrome P450 enzyme (CYP inducers or inhibitors (80%, and up to 11 (of 14 groups of narrow therapeutic index drugs (79%. Interestingly, it was observed that the keywords used to describe a drug characteristic were not necessarily the most predictive ones for the classification task. Conclusions BICEPP has sufficient classification power to automatically distinguish a wide range of clinical properties of drugs. This may be used in pharmacovigilance applications to assist with rapid screening of large drug databases to identify important characteristics for further evaluation.

Evaluation of deformation-strength characteristics of Fiber-cement-stabilized soil by using Distinct Element Method

Science.gov (United States)

Satomi, Tomoaki; Konda, Naoki; Takahashi, Hiroshi

Fiber-cement-stabilized soil method is an effective way to recycle high-water content mud. The modified soil has several advantages such as high failure stress and high failure strain. However, the quality of the modified soil is not constant and depends on the water content of the mud and additives. Therefore, experimental verification to obtain the strength characteristics of the modified soil is necessary, but conducting experiments under various conditions is ineffective and uneconomic. In this study, a numerical model to estimate deformation-strength characteristics of the modified soil is investigated by using Distinct Element Method (DEM). It was shown that the developed model was effective way to estimate deformation-strength characteristics. Moreover, it was confirmed that the modified soil had high earthquake resistance.

Students' Demographic, Academic Characteristics and Performance in Registered General Nursing Licensing Examination in Ghana

Science.gov (United States)

Doe, Patience Fakornam; Oppong, Elizabeth Agyeiwaa; Sarfo, Jacob Owusu

2018-01-01

The decreasing performance of student nurses in the professional licensure examinations (LE) in Ghana is a major concern to stakeholders, especially at a time when the nurse-patient ratio stands at 1: 1500. The study sought to determine the effect of students' demographic and academic characteristics on performance in the Registered General…

Acoustic Characteristics of Simulated Respiratory-Induced Vocal Tremor

Science.gov (United States)

Lester, Rosemary A.; Story, Brad H.

2013-01-01

Purpose: The purpose of this study was to investigate the relation of respiratory forced oscillation to the acoustic characteristics of vocal tremor. Method: Acoustical analyses were performed to determine the characteristics of the intensity and fundamental frequency (F[subscript 0]) for speech samples obtained by Farinella, Hixon, Hoit, Story,…

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...

The impact of ownership and other corporate characteristics on performance of V4 companies

Directory of Open Access Journals (Sweden)

David Procházka

2017-06-01

Full Text Available The objective of this paper is to assess financial performance of Czech, Hungarian, Polish, and Slovak unlisted companies. The sample retrieved from the Amadeus database contains 171,095 firm-year observations for the period of 2010-2014. A linear regression model (weighted least squares with robust correction for standard errors is run to regress Return on Assets (ROA as the dependent variable against selected entity-specific factors, including ownership characteristics. Empirical evidence uncovers several findings. Firstly, the performance of V4 companies is comparable except for Hungary, where companies report lower ROA on average. Secondly, firms established after the failure of communist regimes outperform the privatised companies. Thirdly, the ownership characteristics do matter. Having domestic owners is not a disadvantage, as only the companies with controlling shareholders from the Anglo-Saxon countries perform better. Other jurisdictions of parents lead either to comparable (e.g., old EU members, developed Asian countries or even worse (e.g., new EU members, post-Soviet bloc performance as compared to domestic ownership. Similarly, family firms perform significantly better than the companies controlled by institutional owners or by public sector, but worse than the firms controlled by financial institutions. The listing status of a parent is not an influential factor of performance. Fourthly, the size of a company also matters, as small enterprises report better performance in their financial statements than medium and large undertakings. Fifthly, higher leverage undermines performance. Finally, there is a wide dispersion in average performance across the industries. The study results might be relevant for policy makers while choosing between direct and indirect support for diverse types of businesses.

The impact of green roof ageing on substrate characteristics and hydrological performance

Science.gov (United States)

De-Ville, Simon; Menon, Manoj; Jia, Xiaodong; Reed, George; Stovin, Virginia

2017-04-01

Green roofs contribute to stormwater management through the retention of rainfall and the detention of runoff. However, there is very limited knowledge concerning the evolution of green roof hydrological performance with system age. This study presents a non-invasive technique which allows for repeatable determination of key substrate characteristics over time, and evaluates the impact of observed substrate changes on hydrological performance. The physical properties of 12 green roof substrate cores have been evaluated using non-invasive X-ray microtomography (XMT) imaging. The cores comprised three replicates of two contrasting substrate types at two different ages: unused virgin samples; and 5-year-old samples from existing green roof test beds. Whilst significant structural differences (density, pore and particle sizes, tortuosity) between virgin and aged samples of a crushed brick substrate were observed, these differences did not significantly affect hydrological characteristics (maximum water holding capacity and saturated hydraulic conductivity). A contrasting substrate based upon a light expanded clay aggregate experienced increases in the number of fine particles and pores over time, which led to increases in maximum water holding capacity of 7%. In both substrates, the saturated hydraulic conductivity estimated from the XMT images was lower in aged compared with virgin samples. Comparisons between physically-derived and XMT-derived substrate hydrological properties showed that similar values and trends in the data were identified, confirming the suitability of the non-invasive XMT technique for monitoring changes in engineered substrates over time. The observed effects of ageing on hydrological performance were modelled as two distinct hydrological processes, retention and detention. Retention performance was determined via a moisture-flux model using physically-derived values of virgin and aged maximum water holding capacity. Increased water holding

An acceleration of the characteristics by a space-angle two-level method using surface discontinuity factors

Energy Technology Data Exchange (ETDEWEB)

Grassi, G. [Commissariat a l' Energie Atomique, CEA de Saclay, DM2S/SERMA/LENR, 91191, Gif-sur-Yvette (France)

2006-07-01

We present a non-linear space-angle two-level acceleration scheme for the method of the characteristics (MOC). To the fine level on which the MOC transport calculation is performed, we associate a more coarsely discretized phase space in which a low-order problem is solved as an acceleration step. Cross sections on the coarse level are obtained by a flux-volume homogenisation technique, which entails the non-linearity of the acceleration. Discontinuity factors per surface are introduced as additional degrees of freedom on the coarse level in order to ensure the equivalence of the heterogeneous and the homogenised problem. After each fine transport iteration, a low-order transport problem is iteratively solved on the homogenised grid. The solution of this problem is then used to correct the angular moments of the flux resulting from the previous free transport sweep. Numerical tests for a given benchmark have been performed. Results are discussed. (authors)

An acceleration of the characteristics by a space-angle two-level method using surface discontinuity factors

International Nuclear Information System (INIS)

Grassi, G.

2006-01-01

We present a non-linear space-angle two-level acceleration scheme for the method of the characteristics (MOC). To the fine level on which the MOC transport calculation is performed, we associate a more coarsely discretized phase space in which a low-order problem is solved as an acceleration step. Cross sections on the coarse level are obtained by a flux-volume homogenisation technique, which entails the non-linearity of the acceleration. Discontinuity factors per surface are introduced as additional degrees of freedom on the coarse level in order to ensure the equivalence of the heterogeneous and the homogenised problem. After each fine transport iteration, a low-order transport problem is iteratively solved on the homogenised grid. The solution of this problem is then used to correct the angular moments of the flux resulting from the previous free transport sweep. Numerical tests for a given benchmark have been performed. Results are discussed. (authors)

Implementation of palm biodiesel based on economic aspects, performance, emission, and wear characteristics

International Nuclear Information System (INIS)

Mosarof, M.H.; Kalam, M.A.; Masjuki, H.H.; Ashraful, A.M.; Rashed, M.M.; Imdadul, H.K.; Monirul, I.M.

2015-01-01

Highlights: • Global environmental protection of using alternative fuel. • Economic aspects of palm oil biodiesel in Malaysia. • Tribological characteristics of palm oil biodiesel in engine components. • Engine performance and emission of palm oil biodiesel. • Effect of temperature on density and kinematic viscosity for various biodiesel. - Abstract: The high cost of energy supplies and the growing concern over the dependency on fossil fuels have impelled many countries to search for renewable and alternative energy sources. The extensive use of fossil fuels for transportation and power generation all over the world have caused the supply of fossil fuels to continuously decrease and have aggravated environmental pollution. Searching for alternative fuels has become imperative to reduce pollution and address the problems on fossil fuels. Vegetable oil fuels, such as palm oil biodiesel, serve as alternative forms of energy and are currently being studied, particularly as a diesel fuel substitute. The purpose of this study is to review the potential of palm oil as an energy source and alternative diesel fuel in terms of its performance, environmental impact, wear characteristics, and economic considerations. Compared with other vegetable oils, palm oil is a relatively sustainable, environment-friendly, less expensive, and economically beneficial potential source of energy. Palm oil plantation and production is a major industry in Malaysia, contributing to the economic growth and development of the country. The properties of palm oil biodiesel, namely, high oxidation stability, good cold properties, cetane number, and higher viscosity, makes it a suitable diesel substitute. Compared with other vegetable oils and petroleum diesel fuels, palm oil is associated with better engine performance, higher specific fuel consumption, and shorter ignition delay. Use of palm oil also reduces exhaust emission of hydrocarbon, carbon monoxide, carbon dioxide, and smoke, but

Validated High Performance Liquid Chromatography Method for ...

African Journals Online (AJOL)

Purpose: To develop a simple, rapid and sensitive high performance liquid chromatography (HPLC) method for the determination of cefadroxil monohydrate in human plasma. Methods: Schimadzu HPLC with LC solution software was used with Waters Spherisorb, C18 (5 μm, 150mm × 4.5mm) column. The mobile phase ...

Analysis of the Effect of Individual Characteristics, Employees’ Competency and Organizational Climate on Job Satisfaction and Employees’ Performance at a State-Owned Trading Company in Indonesia

Directory of Open Access Journals (Sweden)

SYAIFUDDIN

2017-08-01

Full Text Available Job satisfaction and employees’ performance are important for the organization to improve the company's competitive value. This research aims to know the influence of individual characteristic, employees’ competency and organizational climate toward job satisfaction and its implication on employees’ performance. The research method used in this research is cross sectional survey. The population of this research was from 4 cities with a total sample of 51 employees. Moreover, this research applied structural equation modeling with Partial Least Square approach for analyzing the data. The results showed that individual characteristics do not effect on job satisfaction, while employees’ competency and organizational climate have a significant effect on job satisfaction. Then, job satisfaction has a significant effect on employees’ performance. It is necessary to conduct training and education programs along with flexible structural support and adequate rewards for the employees to improve the job satisfaction. Those aspects are expected to improve the employees’ performance.

A variable-order time-dependent neutron transport method for nuclear reactor kinetics using analytically-integrated space-time characteristics

International Nuclear Information System (INIS)

Hoffman, A. J.; Lee, J. C.

2013-01-01

A new time-dependent neutron transport method based on the method of characteristics (MOC) has been developed. Whereas most spatial kinetics methods treat time dependence through temporal discretization, this new method treats time dependence by defining the characteristics to span space and time. In this implementation regions are defined in space-time where the thickness of the region in time fulfills an analogous role to the time step in discretized methods. The time dependence of the local source is approximated using a truncated Taylor series expansion with high order derivatives approximated using backward differences, permitting the solution of the resulting space-time characteristic equation. To avoid a drastic increase in computational expense and memory requirements due to solving many discrete characteristics in the space-time planes, the temporal variation of the boundary source is similarly approximated. This allows the characteristics in the space-time plane to be represented analytically rather than discretely, resulting in an algorithm comparable in implementation and expense to one that arises from conventional time integration techniques. Furthermore, by defining the boundary flux time derivative in terms of the preceding local source time derivative and boundary flux time derivative, the need to store angularly-dependent data is avoided without approximating the angular dependence of the angular flux time derivative. The accuracy of this method is assessed through implementation in the neutron transport code DeCART. The method is employed with variable-order local source representation to model a TWIGL transient. The results demonstrate that this method is accurate and more efficient than the discretized method. (authors)

Improved power performance assessment methods

Energy Technology Data Exchange (ETDEWEB)

Frandsen, S; Antoniou, I; Dahlberg, J A [and others

1999-03-01

The uncertainty of presently-used methods for retrospective assessment of the productive capacity of wind farms is unacceptably large. The possibilities of improving the accuracy have been investigated and are reported. A method is presented that includes an extended power curve and site calibration. In addition, blockage effects with respect to reference wind speed measurements are analysed. It is found that significant accuracy improvements are possible by the introduction of more input variables such as turbulence and wind shear, in addition to mean wind speed and air density. Also, the testing of several or all machines in the wind farm - instead of only one or two - may provide a better estimate of the average performance. (au)

Usage of performance measurement and evaluation systems : the impact of evaluator characteristics

OpenAIRE

Gelderman, Maarten

1998-01-01

This paper discusses the relation between characteristics of the evaluating manager and the way performance measurement and evaluation information is used. First a discussion is provided about the dependent variable. It is recognized that categorization into archetypes (e.g., evaluative styles) is unsatisfactory. Instead the information content/emphasis dimensions financial-non- financial, quantitative-qualitative, process-outcome, past-future and external-internal, along with the dimension f...

The Effect of Chinese Propolis Supplementation on Ross Broiler Performance and Carcass Characteristics

Directory of Open Access Journals (Sweden)

Usama T. Mahmoud

2013-10-01

Full Text Available The experiment was conducted to investigate the effects of Ether Extract of Propolis (EEP on Ross (308 broiler performance and carcass characteristics. This experiment was carried out in a completely randomized design with 5 treatments (different levels of propolis including 0, 100, 250, 500 and 750 mg/kg diet for 6 weeks. The mean weight gain, feed consumption and feed conversion ratio were recorded weekly. In addition At 42 days old the total body weight, total body weight gain, carcass and some internal organs relative weights were recorded. The results clarified that, the weight gain was significantly reduced in the 4th and 6th week (P0.05 reduced for propolis fed birds in comparison to those fed control diet, Furthermore, inclusion of 100, 250, 500 and 750 mg/kg diet Propolis significantly reduced body weight at 42 days old and total body weight gain in comparison to control diet (P < 0.05. Under the condition of this experiment, prolonged use of propolis had adverse effect on performance of broilers. Also, all doses of propolis had non-significant negative effect on liver, heart, gizzard and carcass relative weight. In conclusion, EEP has no beneficial effect on performance and Carcass characteristics of Broilers.

Metformin: A Review of Characteristics, Properties, Analytical Methods and Impact in the Green Chemistry.

Science.gov (United States)

da Trindade, Mariana Teixeira; Kogawa, Ana Carolina; Salgado, Hérida Regina Nunes

2018-01-02

Diabetes mellitus (DM) is considered a public health problem. The initial treatment consists of improving the lifestyle and making changes in the diet. When these changes are not enough, the use of medication becomes necessary. The metformin aims to reduce the hepatic production of glucose and is the preferred treatment for type 2. The objective is to survey the characteristics and properties of metformin, as well as hold a discussion on the existing analytical methods to green chemistry and their impacts for both the operator and the environment. For the survey, data searches were conducted by scientific papers in the literature as well as in official compendium. The characteristics and properties are shown, also, methods using liquid chromatography techniques, titration, absorption spectrophotometry in the ultraviolet and the infrared region. Most of the methods presented are not green chemistry oriented. It is necessary the awareness of everyone involved in the optimization of the methods applied through the implementation of green chemistry to determine the metformin.

Performance prediction method for a multi-stage Knudsen pump

Science.gov (United States)

Kugimoto, K.; Hirota, Y.; Kizaki, Y.; Yamaguchi, H.; Niimi, T.

2017-12-01

In this study, the novel method to predict the performance of a multi-stage Knudsen pump is proposed. The performance prediction method is carried out in two steps numerically with the assistance of a simple experimental result. In the first step, the performance of a single-stage Knudsen pump was measured experimentally under various pressure conditions, and the relationship of the mass flow rate was obtained with respect to the average pressure between the inlet and outlet of the pump and the pressure difference between them. In the second step, the performance of a multi-stage pump was analyzed by a one-dimensional model derived from the mass conservation law. The performances predicted by the 1D-model of 1-stage, 2-stage, 3-stage, and 4-stage pumps were validated by the experimental results for the corresponding number of stages. It was concluded that the proposed prediction method works properly.

The method of projected characteristics for the evolution of magnetic arches

Science.gov (United States)

Nakagawa, Y.; Hu, Y. Q.; Wu, S. T.

1987-01-01

A numerical method of solving fully nonlinear MHD equation is described. In particular, the formulation based on the newly developed method of projected characteristics (Nakagawa, 1981) suitable to study the evolution of magnetic arches due to motions of their foot-points is presented. The final formulation is given in the form of difference equations; therefore, the analysis of numerical stability is also presented. Further, the most important derivation of physically self-consistent, time-dependent boundary conditions (i.e. the evolving boundary equations) is given in detail, and some results obtained with such boundary equations are reported.

The effect of morphological characteristics on the physical and physiological performance of Turkish soccer referees and assistant referees

Directory of Open Access Journals (Sweden)

Bozdoğan Tuba Kızılet

2017-01-01

Full Text Available Physical fitness and physiological status play an important role in the referees’ performance. Therefore, the aim of this study was to analyze the body structure and morphological characteristics of Turkish Ssccer refereesand assistant referees and to determine the effect of these variables on physical performance. A sample of 158 male referees and 55 asisstant referees (mean age 31.8 ± 4.2 and 37.4 ± 3.3 yearswas evaluated. Physical assesment were conducted using the Yo-Yo Intermittent Recovery Test Level 1 (YYIRTL1 and Repeated Sprint Ability (RSA for referees and Active Recovery Intermittent Endurance Test (ARIET and the RSA for assistant referees. We analyzed heart rate assesments. The measures used to assess morphological characteristics were age, weight, body mass index (BMI, body fat (BF, body mass, and fat free mass.The ANOVA test (Tukey testwas used to determine the result. Correlations between the referees’ fitness test performance and their morphological characteristics were examined using Pearson’s correlation (p<0.05. To result of this study, point to the existence of a strong correlation between morphological and physical and physiological characteristics. According to the literature, we found that greater BF and a higher BMI may negatively affect areferee’s running performance.

Method of characteristics - Based sensitivity calculations for international PWR benchmark

International Nuclear Information System (INIS)

Suslov, I. R.; Tormyshev, I. V.; Komlev, O. G.

2013-01-01

Method to calculate sensitivity of fractional-linear neutron flux functionals to transport equation coefficients is proposed. Implementation of the method on the basis of MOC code MCCG3D is developed. Sensitivity calculations for fission intensity for international PWR benchmark are performed. (authors)

The effect of surface characteristics of reduced graphene oxide on the performance of a pseudocapacitor

International Nuclear Information System (INIS)

Chang, M S; Kim, T; Kang, J H; Park, J; Park, C R

2015-01-01

In this research, we have analyzed the electrochemical characteristics of the different rGO/Co 3 O 4 composites prepared by controlling the rGO surface characteristics and its relationship between the growth of Co 3 O 4 nanoparticles and the performance of the pseudocapacitor. Reduced graphene oxide/cobalt oxide (rGO/Co 3 O 4 ) nanocomposites of different morphologies were prepared through the simple hydrothermal method. First, different kinds of graphite precursors, crumpled and planar with different properties, were used to determine the most suitable substrate to grow Co 3 O 4 nanoparticles. As a result, rGO/Co 3 O 4 composite synthesized from planar graphite shows a higher specific capacitance of 207.2, 170.1, and 141.5 Fg −1 at 1, 2, and 5 Ag −1 than the one prepared from crumpled graphite. In the second part, planar graphite, confirmed to be the most suitable substrate from the previous part, was oxidized under various oxidation conditions to increase the oxygen functional groups attached on the GO surfaces and observed to see how it affects the growth of Co 3 O 4 nanoparticles and its influence on the electrochemical performance of the rGO/Co 3 O 4 pseudocapacitor. As a result, the one with the largest amount of functional groups had the Co 3 O 4 nanoparticles well dispersed and grown on the rGO substrate in small nanoparticle sizes, as small as 5.9 nm, leading to an improved electrochemical performance. Thus, the specific capacitance with the least amount of oxygen functional groups are 207.2, 170.1, and 141.5 Fg −1 and for the largest amount of functional groups are 411.5, 371.4, and 292.7 Fg −1 , at 1, 2, and 5 Ag −1 respectively. This approach could become a guideline for the ideal fabrication of rGO/metal oxide composite for further research involving rGO based pseudocapacitors. (paper)

Method and apparatus for determining characteristics of clay-bearing formations

International Nuclear Information System (INIS)

Fertl, W.H.; Ruhovets, N.

1986-01-01

This invention relates to methods and apparatus for determining characteristics of clay-bearing geological formations by radioactivity well logging. In its broadest aspect, the invention comprises the steps of determining the volume of clay contained in the earth formations; determining a first property of the formations functionally related to the volume of clay; and determining a second property functionally related to the first property, the second property indicating potential clay swelling. In particular, the volume of clay is determined using electrical signals generated in response to the energy and frequency of detected radiations. The method is carried out with a well logging instrument that includes a high-resolution gamma ray spectrometer that traverses a borehole, whereby natural radiation strikes a scintillation crystal contained therein

Flow characteristics and performance evaluation of butterfly valves using numerical analysis

International Nuclear Information System (INIS)

Jeon, S Y; Shin, M S; Yoon, J Y

2010-01-01

The industrial butterfly valves have been applied to various fields that transport fluid in volume, especially water supply and drainage pipeline for flow control. The butterfly valves in various shapes are manufactured, but a fitting performance comparison is not made up. For this reason, we carried out numerical analysis of some kind of butterfly valves for water supply and drainage pipeline using commercial CFD code FLUENT, and made a comparative study of these results. Also, the flow coefficient, the loss coefficient, and pressure distribution of valves according to valve opening rate were compared each other and the influence of these design variables on valve performance were checked over. Through flow around the valve disk, such as pressure distribution, flow pattern, velocity vectors, and form of vortex, we grasped flow characteristics.

Roasted sesame hulls improve broiler performance without affecting carcass characteristics

Directory of Open Access Journals (Sweden)

Kamel Z. Mahmoud

2015-09-01

Full Text Available An experiment was conducted to evaluate the effect of using graded levels of roasted sesame hulls (RSH on growth performance and meat quality characteristics in broiler chickens. A total of 360 day-old Lohmann chicks were randomly allocated into 24 floor pens and raised over 42 days. One of four dietary treatments was assigned to each group of six pens in a completely randomized fashion. The chicks in the control group were fed a corn-soybean based diet (RSH-0, while the chicks in treatments two, three, and four were fed graded levels of RSH at 4% (RSH-4, 8% (RSH-8, and 12% (RSH-12, respectively. Diets were formulated to meet broiler chicks’ requirements according to the National Research Council for both starter and finisher rations. The results showed that RSH inclusion increased (P<0.05 feed intake and final body weight without adversely affecting the feed conversion ratio. Broiler chicks fed RSH-12 had heavier (P<0.05 breast and leg cuts compared to the control-fed group with no change to their chemical composition. Water holding capacity (WHC, cooking loss (CL, and shear force (SF reported similar results in all dietary groups. The chemical composition of both thigh and breast cuts was not affected by the RSH. After one day of thawing, colour coordinates of breast cuts behaved similarly in all dietary groups. The results of this study suggest that the addition of RSH to broiler diets up to 12% improves their growth performance; nevertheless, carcass characteristics and meat quality showed no alterations compared to the control-fed group.

Optimization method development of the core characteristics of a fast reactor in order to explore possible high performance solutions (a solution being a consistent set of fuel, core, system and safety)

International Nuclear Information System (INIS)

Ingremeau, J.-J.X.

2011-01-01

In the study of any new nuclear reactor, the design of the core is an important step. However designing and optimising a reactor core is quite complex as it involves neutronics, thermal-hydraulics and fuel thermomechanics and usually design of such a system is achieved through an iterative process, involving several different disciplines. In order to solve quickly such a multi-disciplinary system, while observing the appropriate constraints, a new approach has been developed to optimise both the core performance (in-cycle Pu inventory, fuel burn-up, etc...) and the core safety characteristics (safety estimators) of a Fast Neutron Reactor. This new approach, called FARM (Fast Reactor Methodology) uses analytical models and interpolations (Meta-models) from CEA reference codes for neutronics, thermal-hydraulics and fuel behaviour, which are coupled to automatically design a core based on several optimization variables. This global core model is then linked to a genetic algorithm and used to explore and optimise new core designs with improved performance. Consideration has also been given to which parameters can be best used to define the core performance and how safety can be taken into account.This new approach has been used to optimize the design of three concepts of Gas cooled Fast Reactor (GFR). For the first one, using a SiC/SiCf-cladded carbide-fuelled helium-bonded pin, the results demonstrate that the CEA reference core obtained with the traditional iterative method was an optimal core, but among many other possibilities (that is to say on the Pareto front). The optimization also found several other cores which exhibit some improved features at the expense of other safety or performance estimators. An evolution of this concept using a 'buffer', a new technology being developed at CEA, has hence been introduced in FARM. The FARM optimisation produced several core designs using this technology, and estimated their performance. The results obtained show that

Effects of ractopamine hydrochloride on growth performance and carcass characteristics in wool and hair lambs

Directory of Open Access Journals (Sweden)

Ángel M. Romero-Maya

2013-06-01

Full Text Available This study aimed at evaluating the effects of ractopamine hydrochloride (RAC on growth performance and carcass characteristics of wool and hair lambs. For this purpose, 48 lambs averaging 31.3 kg body weight, of which twenty were wool (Ramboullet x Suffolk and twenty eight were hair (Tabasco lambs, and four levels of RAC (0, 10, 20, and 30 mg/kg diet, dry matter basis were used. Wool lambs fed 20 and 30 mg RAC had higher (P<0.05 total gain weight and lower feed conversion than 0 and 10 mg RAC. Wool lambs fed 20 mg RAC had the highest carcass weight, dressing, legs weight and longissimus area as compared to 0, 10 and 30 mg RAC.  In hair lambs there were not effect of RAC on growth performance and carcass characteristics.It was concluded that addition of RAC to finishing diets offered the best growth performance and carcass traits in wool lambs as compared to hair lambs. 

HVDC System Characteristics and Simulation Models

Energy Technology Data Exchange (ETDEWEB)

Moon, S.I.; Han, B.M.; Jang, G.S. [Electric Enginnering and Science Research Institute, Seoul (Korea)

2001-07-01

This report deals with the AC-DC power system simulation method by PSS/E and EUROSTAG for the development of a strategy for the reliable operation of the Cheju-Haenam interconnected system. The simulation using both programs is performed to analyze HVDC simulation models. In addition, the control characteristics of the Cheju-Haenam HVDC system as well as Cheju AC system characteristics are described in this work. (author). 104 figs., 8 tabs.

Convergence analysis of CMADR acceleration for the method of characteristics

International Nuclear Information System (INIS)

Park, Young Ryong; Cho, Nam Zin

2005-01-01

As the nuclear reactor core becomes more complex, heterogeneous, and geometrically irregular, the method of characteristics (MOC) is gaining its wide use in the neutron transport calculations. However, the long computer times require good acceleration methods. In our previous paper, the concept of coarse-mesh angular dependent rebalance (CMADR) acceleration was described and applied to the MOC calculations. The method is based on angular dependent rebalance factors defined on the coarse-mesh boundaries; a coarse-mesh consists of several fine meshes that may be (1) heterogeneous and (2) of mixed geometries with irregular or unstructured mesh shapes. In addition, (3) the coarse-mesh boundaries may not coincide with the structural interfaces of the problem and can be chosen artificially for convenience. The CMADR acceleration method on the MOC scheme that enables the very desirable features (1), (2), and (3) above is new in the neutron transport literature to the best of the authors knowledge. In this paper, we analyze the convergence of CMADR acceleration for MOC calculation in x-y-z (infinite) geometry by using Fourier analysis

Epilepsy in the School Aged Child: Cognitive-Behavioral Characteristics and Effects on Academic Performance.

Science.gov (United States)

Black, Kathryn C.; Hynd, George W.

1995-01-01

Children with epilepsy frequently display cognitive sequelae that are overlooked or misunderstood by educational personnel, yet may adversely impact academic performance. Reviews common cognitive-behavioral characteristics of children with epilepsy, typical effects of anticonvulsant medications, and various periictal phenomena and their relative…

Investigation of Thermal Performance for Atria: a Method Overview

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Moosavi Leila

2016-01-01

Full Text Available The importance of low energy design in large buildings has encouraged researchers to implement different methods for predicting a building’s thermal performance. Atria, as energy efficient features, have been implemented to improve the indoor thermal environment in large modern buildings. Though widely implemented, the thorough study of atrium performance is restricted due to its large size, complex thermodynamic behavior and the inaccuracies and limitations of available prediction tools. This study reviews the most common research tools implemented in previous researches on atria thermal performance, to explore the advantages and limitation of different methods for future studies. The methods reviewed are analytical, experimental, computer modelling and a combination of any or all of these methods. The findings showed that CFD (computational fluid dynamic models are the most popular tools of recent due to their higher accuracy, capabilities and user-friendly modification. Although the experimental methods were reliable for predicting atria thermal and ventilation performance, they have mostly been used to provide data for validation of CFD models. Furthermore, coupling CFD with other experimental models could increase the reliability and accuracy of the models and provide a more comprehensive analysis.

Personality, Assessment Methods and Academic Performance

Science.gov (United States)

Furnham, Adrian; Nuygards, Sarah; Chamorro-Premuzic, Tomas

2013-01-01

This study examines the relationship between personality and two different academic performance (AP) assessment methods, namely exams and coursework. It aimed to examine whether the relationship between traits and AP was consistent across self-reported versus documented exam results, two different assessment techniques and across different…

How Do Board Characteristics Influence Business Performance? Evidence from Non-life Insurance Firms in Zimbabwe

Directory of Open Access Journals (Sweden)

Maxwell Sandada

2015-08-01

Full Text Available The purpose of this study was to contribute to the corporate governance literature by establishing the relationship between board characteristics and corporate performance within the nonlife insurance firms in Zimbabwe. The study sought to provide some insights on corporate governance since the phenomenon is relatively an emerging discipline in Zimbabwe. The paper sought to complement other corporate governance studies that were conducted in other environments by producing evidence on the phenomenon from a developing country context. A quantitative research approach was adopted and respondents were selected through a stratified random sampling. The results of the study confirm that board characteristics (board composition, diversity, and size exhibit a statistically significant positive predictive relationship with the performance of non-life insurance firms measured by gross premium written and customer retention. However, CEO/Chairman duality showed a negative relationship with business performance. Non-life insurance companies need to be cognizant of board characteristics in order to improve their performance. Moreover , the findings in this research has practical relevance for the selection process of directors as it highlights the importance of having a sizeable number of board members as well as an appropriate mix of competences and qualifications on the board. Although corporate governance is has been extensively researched, there is limited study in this area from a developing country like Zimbabwe with relatively less developed capital markets. It would be wrong to assume that the findings found in other countries can apply here because the conditions are different.

Estimating grass and grass silage degradation characteristics by in situ and in vitro gas production methods

Directory of Open Access Journals (Sweden)

Danijel Karolyi

2010-01-01

Full Text Available Fermentation characteristics of grass and grass silage at different maturities were studied using in situ and in vitro gas production methods. In situ data determined difference between grass and silage. Degradable fraction decreased as grass matured while the undegradable fraction increased. Rate of degradation (kd was slower for silage than fresh grass. Gas production method (GP data showed that fermentation of degradable fraction was different between stage of maturity in both grass and silage. Other data did not show any difference with the exception for the rate of GP of soluble and undegradable fraction. The in situ degradation characteristics were estimated from GP characteristics. The degradable and undegradable fractions could be estimated by multiple relationships. Using the three-phases model for gas production kd and fermentable organic matter could be estimated from the same parameters. The only in situ parameter that could not be estimated with GP parameters was the soluble fraction. The GP method and the three phases model provided to be an alternative to the in situ method for animal feed evaluations.

An Online Premium? Characteristics and Performance of Online versus Face-to-Face Students in Principles of Microeconomics

Science.gov (United States)

Dendir, Seife

2016-01-01

The author uses data from two Principles of Microeconomics courses to examine differences in characteristics and performance of online versus face-to-face students. The analysis indicates that even in a traditional institution, the two delivery modes may be serving students with distinctly different backgrounds and characteristics. In terms of…

Supervisors' Performance Ratings Correlated with Selected Personal Characteristics of Attendants in a Mental Retardation Developmental Center.

Science.gov (United States)

Frederick, Joseph; And Others

A research study investigated the relationship between personal characteristics and selected demographic data of 75 attendants in a mental retardation developmental center and the assessment by 24 administrators of the attendants' job performance. Instruments used included a 20-item Direct Care Performance Scale and the Demographic Data Scale,…

Development of a consistent Monte Carlo-deterministic transport methodology based on the method of characteristics and MCNP5

International Nuclear Information System (INIS)

Karriem, Z.; Ivanov, K.; Zamonsky, O.

2011-01-01

This paper presents work that has been performed to develop an integrated Monte Carlo- Deterministic transport methodology in which the two methods make use of exactly the same general geometry and multigroup nuclear data. The envisioned application of this methodology is in reactor lattice physics methods development and shielding calculations. The methodology will be based on the Method of Long Characteristics (MOC) and the Monte Carlo N-Particle Transport code MCNP5. Important initial developments pertaining to ray tracing and the development of an MOC flux solver for the proposed methodology are described. Results showing the viability of the methodology are presented for two 2-D general geometry transport problems. The essential developments presented is the use of MCNP as geometry construction and ray tracing tool for the MOC, verification of the ray tracing indexing scheme that was developed to represent the MCNP geometry in the MOC and the verification of the prototype 2-D MOC flux solver. (author)

A New Processing Method Combined with BP Neural Network for Francis Turbine Synthetic Characteristic Curve Research

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Junyi Li

2017-01-01

Full Text Available A BP (backpropagation neural network method is employed to solve the problems existing in the synthetic characteristic curve processing of hydroturbine at present that most studies are only concerned with data in the high efficiency and large guide vane opening area, which can hardly meet the research requirements of transition process especially in large fluctuation situation. The principle of the proposed method is to convert the nonlinear characteristics of turbine to torque and flow characteristics, which can be used for real-time simulation directly based on neural network. Results show that obtained sample data can be extended successfully to cover working areas wider under different operation conditions. Another major contribution of this paper is the resampling technique proposed in the paper to overcome the limitation to sample period simulation. In addition, a detailed analysis for improvements of iteration convergence of the pressure loop is proposed, leading to a better iterative convergence during the head pressure calculation. Actual applications verify that methods proposed in this paper have better simulation results which are closer to the field and provide a new perspective for hydroturbine synthetic characteristic curve fitting and modeling.

Specific smartphone usage and cognitive performance affect gait characteristics during free-living and treadmill walking.

Science.gov (United States)

Niederer, Daniel; Bumann, Anke; Mühlhauser, Yvonne; Schmitt, Mareike; Wess, Katja; Engeroff, Tobias; Wilke, Jan; Vogt, Lutz; Banzer, Winfried

2018-04-06

Mobile phone tasks like texting, typing, and dialling during walking are known to impact gait characteristics. Beyond that, the effects of performing smartphone-typical actions like researching and taking self-portraits (selfie) on gait have not been investigated yet. We aimed to investigate the effects of smartphone usage on relevant gait characteristics and to reveal potential association of basic cognitive and walking plus smartphone dual-task abilities. Our cross-sectional, cross-over study on physically active, healthy participants was performed on two days, interrupted by a 24-h washout in between. Assessments were: 1) Cognitive testing battery consisting of the trail making test (TMT A and B) and the Stroop test 2) Treadmill walking under five smartphone usage conditions: no use (control condition), reading, dialling, internet searching and taking a selfie in randomized order. Kinematic and kinetic gait characteristics were assessed to estimate conditions influence. In our sample of 36 adults (24.6 ± 1 years, 23 female, 13 male), ANCOVAs followed by post-hoc t-tests revealed that smartphone usage impaired all tested gait characteristics: gait speed (decrease, all conditions): F = 54.7, p smartphone usage was systematically associated with the TMT B time regarding cadence and double stride length for reading (r = -0.37), dialling (r = -0.35) and taking a selfie (r = -0.34). Smartphone usage substantially impacts walking characteristics in most situations. Changes of gait patterns indicate higher cognitive loads and lower awareness. Copyright © 2018 Elsevier B.V. All rights reserved.

Influence of the receiver’s back surface radiative characteristics on the performance of a heat-pipe evacuated-tube solar collector

International Nuclear Information System (INIS)

Zheng, Hongfei; Xiong, Jianying; Su, Yuehong; Zhang, Haiyin

2014-01-01

Highlights: • A model for describing the heat transfer characteristics of the ETSC is derived. • A method by performing roughness treatment is proposed to change the emissivity. • Increasing the receiver’s back surface emissivity can greatly affect the heat loss. • Real weather test verifies the proposed method in controlling overheat phenomenon. - Abstract: The receiver’s back surface radiative characteristics of a heat-pipe evacuated-tube solar collector (ETSC) may have a significant influence on its performance. This influence is generally related to the back surface emissivity and temperature; however it has been not studied previously. This paper firstly presents a heat transfer model for the ETSC, which is then derived to characterize the relationship between the heat loss and the back surface emissivity of the ETSC. A steady state experiment has been also performed to measure the heat loss of ETSC with different back surface emissivity values. The experimental results indicate that the heat loss of the ETSC increases with the increase of the back surface emissivity, but the rate of increase differs for different operation temperatures. When the back surface emissivity increases from 0.03 to 0.12, the heat loss of ETSC only increases by 31% when the operation temperature is below 100 °C, but the heat loss will increase to 96% when the operation temperature is over 200 °C. This means that the change of back surface emissivity can significantly affect the performance of the ETSC at higher temperature but affect little at lower temperature. Based on this, a novel method by performing roughness treatment on the receiver’s back surface is proposed to solve the overheating problem of ETSC in summer. Two solar water heaters including 6 ETSCs with standard and roughness-treated tubes were tested under real weather condition. Experiment reveals that when the water temperature in tank is below 60 °C, the two solar water heaters own similar temperature

A study on the performance and emission characteristics of esterified pinnai oil tested in VCR engine.

Science.gov (United States)

Ashok Kumar, T; Chandramouli, R; Mohanraj, T

2015-11-01

Biodiesel is a clean renewable fuel derived from vegetable oils and animal fats. It is biodegradable, oxygenated, non toxic and free from sulfur and aromatics. The biodiesel prepared from pinnai oil undergoes acid esterification followed by alkaline transesterification process. The fatty acid methyl esters components were identified using gas chromatography and compared with the standard properties. The properties of biodiesel are comparable with diesel. The yield of the biodiesel production depends upon the process parameters such as reaction temperature, pH, time duration and amount of catalyst. The yield of biodiesel by transesterification process was 73% at 55°C. This fuel was tested in a variable compression ratio engine with blend ratios of B10 and B20. During the test runs the compression ratio of the engine was varied from 15:1 to 18:1 and the torque is adjusted from zero to maximum value of 22Nm. The performance characteristics such as the brake thermal efficiency, brake specific energy consumption and exhaust gas temperature of the engine are analyzed. The combustion characteristics of biodiesel like ignition delay, combustion duration and maximum gas temperature and the emission characteristics are also analyzed. The performance characteristics, combustion characteristics and engine emission are effective in the variable compression ratio engine with biodiesel and it is compared with diesel. Copyright © 2015 Elsevier Inc. All rights reserved.

Physical performance characteristics of high-level female soccer players 12-21 years of age.

Science.gov (United States)

Vescovi, J D; Rupf, R; Brown, T D; Marques, M C

2011-10-01

Performance assessment has become an invaluable component of monitoring player development and within talent identification programs in soccer, yet limited performance data are available for female soccer players across a wide age range. The aim of this study was to describe the physical performance characteristics of female soccer players ranging in age from 12 to 21 years. High-level female soccer players (n=414) were evaluated on linear sprinting (36.6 m with 9.1 m splits), countermovement jump (CMJ), and two agility tests. Separate one-way ANOVAs were used to compare performance characteristics between (1) each year of chronological age and (2) three age groups: 12-13 years, n=78, 14-17 years, n=223, and 18-21 years, n=113. Mean linear sprint speed over 9.1 m was similar across all chronological ages, however sprint speed over the final 9.1 m, CMJ height and agility scores improved until approximately 15-16 years. Outcomes from the group data indicated better performance on all tests for the 14-17-year-old group compared with the 12-13-year-old group. Additionally, sprint speed on the second and fourth 9.1 m splits and 36.6 m sprint speed as well as performance on the Illinois agility test was better in the 18-21-year-old group compared with the 14-17-year-old group. The findings from this study indicate that marked improvements of high intensity short duration work occur up until 15-16 years. Smaller gains in performance were observed beyond 16 years of age as evidenced by better performance on 36.6 m sprint speed, several sprint splits and the Illinois agility test in the college aged players (i.e., 18-21-year-old group). © 2010 John Wiley & Sons A/S.

Performance Characteristics of Hero's Turbine Using Hot Water as a Working Fluid

OpenAIRE

FUJII, Terushige; OHTA, Jun-ichi; AKAGAWA, Koji; NAKAMURA, Toshi; ASANO, Hitoshi

1992-01-01

From the viewpoint of energy conservation and the development of new energy resources,it is important to utilize geothermal resources and waste heat from factories. Among energy conversion device,there is a radial outflow reaction turbine,i.e.,Hero's turbine. Performance characteristics of Hero's turbine are analytically and experimentally clarified for flashing expansion of initially subcooled hot water. It is found that: (a)there is an optimum number of revolutions at which maximum tubine e...

Resource Isolation Method for Program’S Performance on CMP

Science.gov (United States)

Guan, Ti; Liu, Chunxiu; Xu, Zheng; Li, Huicong; Ma, Qiang

2017-10-01

Data center and cloud computing are more popular, which make more benefits for customers and the providers. However, in data center or clusters, commonly there is more than one program running on one server, but programs may interference with each other. The interference may take a little effect, however, the interference may cause serious drop down of performance. In order to avoid the performance interference problem, the mechanism of isolate resource for different programs is a better choice. In this paper we propose a light cost resource isolation method to improve program’s performance. This method uses Cgroups to set the dedicated CPU and memory resource for a program, aiming at to guarantee the program’s performance. There are three engines to realize this method: Program Monitor Engine top program’s resource usage of CPU and memory and transfer the information to Resource Assignment Engine; Resource Assignment Engine calculates the size of CPU and memory resource should be applied for the program; Cgroups Control Engine divide resource by Linux tool Cgroups, and drag program in control group for execution. The experiment result show that making use of the resource isolation method proposed by our paper, program’s performance can be improved.

Study of performance and emission characteristics of a partially coated LHR SI engine blended with n-butanol and gasoline

Directory of Open Access Journals (Sweden)

Nitesh Mittal

2013-09-01

Full Text Available To meet the present requirements of the automotive industry, there is continuous search to improve the performance, exhaust emission, and life of the IC engines. The meet the first two challenges, researchers are working both on newer engine technologies and fuels. Some of the published work indicates that coating on the combustion surface of the engine with ceramic material results in improved performance and reduced emission levels when fueled with alternate fuel blended fuels, and this serves as a base for this work. Normal-Butanol has molecular structure that is adaptable to gasoline, and it is considered as one of the alternative fuels for SI engines. Blending butanol with gasoline changes the properties of the fuel and alters the engine performance and emission characteristics. This is because heat which is released at a rate as a result of combustion of the compressed air–fuel mixture in the combustion chamber gets changed with respect to change fuel properties, air fuel ratio, and engine speed. An experimental investigation is carried out on a partially insulated single cylinder SI engine to study the performance and emission characteristics when fueled with two different blends of butanol and gasoline. The cylinder head surface and valves are coated with a ceramic material consisting of Zirconium dioxide (ZrO2 with 8% by weight of Yttrium Oxide (Y2O3 to a thickness of 0.3 mm by plasma spray method. Two different fuel blends containing 10% and 15% by volume of butanol in Gasoline are tested on an engine dynamometer using the uncoated and ceramic coated engines. The results strongly indicate that combination of ceramic coated engine and butanol gasoline blended fuel has potential to improve the engine performance.

ANFIS-Based Modeling for Photovoltaic Characteristics Estimation

Directory of Open Access Journals (Sweden)

Ziqiang Bi

2016-09-01

Full Text Available Due to the high cost of photovoltaic (PV modules, an accurate performance estimation method is significantly valuable for studying the electrical characteristics of PV generation systems. Conventional analytical PV models are usually composed by nonlinear exponential functions and a good number of unknown parameters must be identified before using. In this paper, an adaptive-network-based fuzzy inference system (ANFIS based modeling method is proposed to predict the current-voltage characteristics of PV modules. The effectiveness of the proposed modeling method is evaluated through comparison with Villalva’s model, radial basis function neural networks (RBFNN based model and support vector regression (SVR based model. Simulation and experimental results confirm both the feasibility and the effectiveness of the proposed method.

Performance Characteristics of a Cross-Flow Hydrokinetic Turbine under Unsteady Conditions

Science.gov (United States)

Flack, Karen; Lust, Ethan; Bailin, Ben

2017-11-01

Performance characteristics are presented for a cross-flow hydrokinetic turbine designed for use in a riverine environment. The test turbine is a 1:6 scale model of a three-bladed device (9.5 m span, 6.5 m diameter) that has been proposed by the Department of Energy. Experiments are conducted in the large towing tank (116 m long, 7.9 m wide, 5 m deep) at the United States Naval Academy. The turbine is towed beneath a moving carriage at a constant speed in combination with a shaft motor to achieve the desired tip speed ratio (TSR) range. The measured quantities of turbine thrust, torque and RPM result in power and thrust coefficients for a range of TSR. Results will be presented for cases with quiescent flow at a range of Reynolds numbers and flow with mild surface waves, representative of riverine environments. The impact of unsteady flow conditions on the average turbine performance was not significant. Unsteady flow conditions did have an impact on instantaneous turbine performance which operationally would result in unsteady blade loading and instantaneous power quality.

Are there any differences in power performance and morphological characteristics of Croatian adolescent soccer players according to the team position?

Science.gov (United States)

Sporis, Goran; Vucetić, Vlatko; Jovanović, Mario; Milanović, Zoran; Rucević, Marijan; Vuleta, Dinko

2011-12-01

The aim of the study was to analyze differences in power performance and morphological characteristics of young Croatian soccer players with respect to their team positions and to establish correlations between the power performance variables. Anthropometric characteristics and jumping and sprint performances were analyzed for 45 soccer players (age 14-15; mean body height 175.4 +/- 6.61 cm; body weight 63.6 +/- 8.06 kg) according to their team positions (defender, midfielder, forward). Pearsons coefficient of correlation was used to determine the relationship between the power performance variables. There were no significant differences (p > 0.05) in the power performance of players according to their team position. The only significant differences between players were in some of the anthropometric characteristics, such as height and weight linear relationship was determined between almost all the power performance variables. Since the players in this study were very young and their sports careers have not reached their peak performance, it is possible that their nominal team positions may change during their soccer careers.

The study of structural characteristic of yttrium(3+) aquaion by density functional methods

International Nuclear Information System (INIS)

Buz'ko, V.Yu.; Sukhno, I.V.; Polushin, A.A.; Panyushkin, V.T.

2006-01-01

Structural characteristics of the yttrium aquaion Y(H 2 O) 8 3+ are calculated by DFT technique using density functionals SVWN5, B3LYP, B3P86, O3LYP, B3PW91, B1LYP, B971, MPW1PW9, PBE1PBE, BHandH and BNandHLYP. All calculations are carried out by means of GAUSSIAN-03 code. Structural characteristics of the Y(H 2 O) 8 3+ aquaion obtained by the use of the density functional method agree satisfactorily with the experiment. Hybrid nonlocal GGA-functionals foretell worse the structural characteristics of the Y(H 2 O) 8 3+ aquaion as compared with the reasonable simple combined functional BHandH and the simplest functional SVWN5 of the LSDA theory [ru

Performance Characteristic of a CsI(Tl) Flat Panel Detector Radiography System

International Nuclear Information System (INIS)

Jeong, Hoi Woun; Min, Jung Hwan; Kim, Jung Min; Park, Min Seok; Lee, Gaung Young

2012-01-01

The purpose of this work was to evaluate an amorphous silicon cesium iodide based indirect flat-panel detector (FPD) in terms of their modulation transfer function (MTF), Wiener spectrum (WS, or noise power spectrum, NPS), and detective quantum efficiency (DQE). Measurements were made on flat-panel detector using the International Electrotechnical Commission (IEC) defined RQA3, RQA5, RQA7, and RQA9 radiographic technique. The MTFs of the systems were measured using an edge method. The WS(NPS) of the systems were determined for a range of exposure levels by two-dimensional (2D). Fourier analysis of uniformly exposed radiographs. The DQEs were assessed from the measured MTF, WS(NPS), exposure, and estimated ideal signal-to-noise ratios. Characteristic curve in the RQA3 showed difference in the characteristic curve from RQA5, RQA7, RQA9. MTFs were not differences according to x-ray beam quality. WS(NPS) was reduced with increasing dose, and RQA 3, RQA5, RQA7, RQA9 as the order is reduced. DQE represented the best in the 1mR, RQA 3, RQA5, RQA7, RQA9 decrease in the order. The physical imaging characteristics of FPD may also differ from input beam quality. This study gives an initial motivation that the physical imaging characteristics of FPD is an important issue for the right use of digital radiography system.

Performance Characteristic of a CsI(Tl) Flat Panel Detector Radiography System

Energy Technology Data Exchange (ETDEWEB)

Jeong, Hoi Woun [Dept. of Radiological Science, Baekseok Culture University, Seoul (Korea, Republic of); Min, Jung Hwan [Dept. of Radiological Technology, Shingu University, Seongnam (Korea, Republic of); Kim, Jung Min [Dept. of Radiological Science, Korea University, Health Science College, Seoul (Korea, Republic of); Park, Min Seok [Korea Institue of Radiological and Medical Sicences, Research Institute of Radiologycal and Medical Sciences, Seoul (Korea, Republic of); Lee, Gaung Young [National Institute of Food and Drug Safety Evaluation, Seoul (Korea, Republic of)

2012-06-15

The purpose of this work was to evaluate an amorphous silicon cesium iodide based indirect flat-panel detector (FPD) in terms of their modulation transfer function (MTF), Wiener spectrum (WS, or noise power spectrum, NPS), and detective quantum efficiency (DQE). Measurements were made on flat-panel detector using the International Electrotechnical Commission (IEC) defined RQA3, RQA5, RQA7, and RQA9 radiographic technique. The MTFs of the systems were measured using an edge method. The WS(NPS) of the systems were determined for a range of exposure levels by two-dimensional (2D). Fourier analysis of uniformly exposed radiographs. The DQEs were assessed from the measured MTF, WS(NPS), exposure, and estimated ideal signal-to-noise ratios. Characteristic curve in the RQA3 showed difference in the characteristic curve from RQA5, RQA7, RQA9. MTFs were not differences according to x-ray beam quality. WS(NPS) was reduced with increasing dose, and RQA 3, RQA5, RQA7, RQA9 as the order is reduced. DQE represented the best in the 1mR, RQA 3, RQA5, RQA7, RQA9 decrease in the order. The physical imaging characteristics of FPD may also differ from input beam quality. This study gives an initial motivation that the physical imaging characteristics of FPD is an important issue for the right use of digital radiography system.

Performance characteristics of axisymmetric venturi-like reverse-flow diverters. Consolidated Fuel Reprocessing Program

International Nuclear Information System (INIS)

Smith, G.V.; Counce, R.M.

1984-01-01

This paper presents experimental and model-predicted pressure-flow characteristics of axisymmetric venturi-like reverse-flow diverters (RFDs), the key component of fluid pumping systems utilized for the transport of hazardous fluids. The effects of several key geometric parameters, operating conditions, and fluid properties on the performance of the RFD are presented and compared to model predictions. The results indicate good agreement between data and theory over a large portion of the range of variables studied. Cavitation is observed to be the primary factor in limiting the performance of the RFD at small values of load impedances

Simulation and Experimental Investigation of Structural Dynamic Frequency Characteristics Control

Directory of Open Access Journals (Sweden)

Bing Li

2012-04-01

Full Text Available In general, mechanical equipment such as cars, airplanes, and machine tools all operate with constant frequency characteristics. These constant working characteristics should be controlled if the dynamic performance of the equipment demands improvement or the dynamic characteristics is intended to change with different working conditions. Active control is a stable and beneficial method for this, but current active control methods mainly focus on vibration control for reducing the vibration amplitudes in the time domain or frequency domain. In this paper, a new method of dynamic frequency characteristics active control (DFCAC is presented for a flat plate, which can not only accomplish vibration control but also arbitrarily change the dynamic characteristics of the equipment. The proposed DFCAC algorithm is based on a neural network including two parts of the identification implement and the controller. The effectiveness of the DFCAC method is verified by several simulation and experiments, which provide desirable results.

Performance and carcass characteristics of lambs fed on diets supplemented with glycerin from biodiesel production

Directory of Open Access Journals (Sweden)

Marco Antonio Bensimon Gomes

2011-10-01

Full Text Available This study was carried out to evaluate the influence of diets supplemented with glycerin as an alternative ingredient to corn on the performance and carcass characteristics of Santa Inês confined lambs. The study involved 27 lambs aged 90 days, having an average initial weight of 26.33 ± 0.15 kg. Lambs were randomly distributed into a control group and groups with diets containing 15 and 30% glycerin in the total feed. Diet was formulated with 40% roughage and 60% concentrate. The experimental design was completely randomized, and the production performance and carcass characteristics were analyzed by analysis of variance, and the subjective carcass characteristics, by general linear models. The daily average gain was 0.21, 0.24 and 0.23 kg/day; feeding conversion was 6.39, 5.73 and 5.92 kg of diet/kg BW for control animals, and those fed with 15 or 30% glycerin, respectively, without treatment differences. Lambs were slaughtered, weighing 34 to 36 kg, and average weight of the cold carcass and commercial carcass yield were evaluated. The results were, respectively, 15.97 kg and 49.18%, for control, 15.96 kg and 48.31% for animals fed with 15% glycerin, and 15.79 kg and 47.87% for those treated with 30% glycerin, with no treatment effects. Meat tenderness and cooking loss averages were not affected by diets, with 5.07 kg and 40.45%, 5.10 kg and 40.81%, and 5.27 kg and 39.04%, respectively, for control, and those fed with 15 or 30% glycerin. Therefore, it is possible to conclude that up to 30% of medium purity glycerin in the dry matter of the diet can be used to replace corn, without any negative effect on lamb performance or carcass characteristics.

Analysis of Professional and Pre-Accession Characteristics and Junior Naval Officer Performance

Science.gov (United States)

2018-03-01

OIC Officer in Charge OPINS Officer Personnel Information System PES Performance Evaluation System PET Performance Evaluation Transformation RL...identify and promote talent, the Navy is undergoing a Performance Evaluation Transformation (PET) aimed at tracking performance and professional...method the Navy uses to identify skills, education , training, experience and capabilities related to both officer personnel and manpower requirements

Thermoluminescent characteristics of synthetic hydroxyapatite (SHAp)

International Nuclear Information System (INIS)

Alvarez, R.; Rivera, T.; Guzman, J.; Piña-Barba, M.C.; Azorin, J.

2014-01-01

This paper presents the experimental results of the thermoluminescent (TL) characteristics of synthetic hydroxyapatite (SHAp) obtained by the sol–gel method. For preparation of the SHAp powders, phosphorus pentoxide (P 2 O 5 ) and calcium nitrate tetrahydrated (Ca(NO 3 ) 2 –4H 2 O) were used. The powders obtained were submitted at different temperatures. The structural and morphological characterization were carried out using X-ray diffraction (XRD) and scanning electron microscopy techniques. TL glow curve exhibited two peaks centered at around 200 °C and 300 °C. TL response of SHAp as a function of gamma absorbed dose was linear over a wide dose range. Fading of the storage information in the samples irradiated was also studied. The experimental results show that the synthetic hydroxyapatite obtained by the sol–gel method may have used in gamma radiation dosimetry applications. - highlights: • Dosimetric characteristics of SHAp under gamma irradiation effect were analyzed • SHAp powders were obtained by Sol–Gel method • Fading anomalous of HAp was performed showing 15% during 90 days • SHAp showed good dosimetric characteristics. • Dosimetric characteristics of SHAp have not been reported yet in the literature before this paper

A study on the characteristics of the spacer spring by finite element method

Energy Technology Data Exchange (ETDEWEB)

Park, Sung Keun; Kim, Hyung Kyu; Kim, Kyu Tae [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-06-01

The mechanical integrity of spacer springs in KOFA was certified through the mechanical tests by KWU. In this report, the spacer spring characteristics were obtained by using a commercial FEM code ANSYS, and the calculated results were compared with the mechanical test results. It has been found that the analytical results from ANSYS were in good agreement with the test results in the actual working range of the spacer springs even though some errors occurred in the range of initial spring deflection. The errors were thought to occur due to the simplified boundary conditions and the nominal dimensions which are used in calculations rather than the as-fabricated dimensions. Though the results from ANSYS are not fully satisfied, the analytical method in this report has been verified to be used as a method for investigating the characteristic of spacer springs roughly before conducting mechanical tests. 8 tabs., 25 figs (Author) .new.

Integrated Safety and Security Risk Assessment Methods: A Survey of Key Characteristics and Applications

OpenAIRE

Chockalingam, Sabarathinam; Hadziosmanovic, Dina; Pieters, Wolter; Teixeira, Andre; van Gelder, Pieter

2017-01-01

Over the last years, we have seen several security incidents that compromised system safety, of which some caused physical harm to people. Meanwhile, various risk assessment methods have been developed that integrate safety and security, and these could help to address the corresponding threats by implementing suitable risk treatment plans. However, an overarching overview of these methods, systematizing the characteristics of such methods, is missing. In this paper, we conduct a systematic l...

Investigation of the spray characteristics for a secondary fuel injection nozzle using a digital image processing method

Science.gov (United States)

Jeong, Haeyoung; Lee, Kihyung; Ikeda, Yuji

2007-05-01

There are many ways to reduce diesel engine exhaust emissions. However, NOx emission is difficult to reduce because the hydrocarbon (HC) concentration in a diesel engine is not sufficient for NOx conversion. Therefore, in order to create stoichiometric conditions in the De-NOx catalyst, a secondary injection system is designed to inject liquid HC into the exhaust pipe. The atomization and distribution characteristics of the HC injected from a secondary injector are key technologies to obtain a high NOx conversion because inhomogeneous droplets of injected HC cause not only high fuel consumption but also deterioration of NOx emission. This paper describes the spray characteristics of a secondary injector including the spray angle, penetration length and breakup behaviour of the spray to optimize the reduction rate of the NOx catalyst. In this study, various optical diagnostics were applied to investigate these spray characteristics, the atomization mechanism and spray developing process. The visualization and image processing method for the spray pulsation were developed by high speed photography. The influence of the fuel supply pressure on the spray behaviour and a more detailed spray developing process have been analysed experimentally using image processing. Finally, the experimental results were used to correlate the spray structure to the injection system performance and to provide a design guide for a secondary injector nozzle.

Performance characteristics for advanced control systems

International Nuclear Information System (INIS)

Kisner, R.A.

1989-01-01

A growing collection of control techniques is becoming available to the design engineer. This make selection of the most appropriate technique for a given application a difficult task. A systematic approach to evaluating alternative control schemes is needed. The approach discussed in this paper expands the traditional concepts of quantitative performance analysis to include other relevant factors such as robustness of the technique, resource requirements, and effects on operators and other personnel. This collection of factors, termed measures of utility, may be used as qualitative and quantitative means of evaluating and comparing properties of alternative control system designs. This paper, although not an in-depth study, serves to outline several measures of utility and suggests a general structure for control system development. This method of comparing the usefulness of alternative control system will prove valuable to the ORNL Advanced Controls Program (ACTO) for optimizing compatibility with actual systems and equipment

Performance characteristics of magnetic resonance imaging without contrast agents or sedation in pediatric appendicitis.

Science.gov (United States)

Didier, Ryne A; Hopkins, Katharine L; Coakley, Fergus V; Krishnaswami, Sanjay; Spiro, David M; Foster, Bryan R

2017-09-01

Magnetic resonance imaging (MRI) has emerged as a promising modality for evaluating pediatric appendicitis. However optimal imaging protocols, including roles of contrast agents and sedation, have not been established and diagnostic criteria have not been fully evaluated. To investigate performance characteristics of rapid MRI without contrast agents or sedation in the diagnosis of pediatric appendicitis. We included patients ages 4-18 years with suspicion of appendicitis who underwent rapid MRI between October 2013 and March 2015 without contrast agent or sedation. After two-radiologist review, we determined performance characteristics of individual diagnostic criteria and aggregate diagnostic criteria by comparing MRI results to clinical outcomes. We used receiver operating characteristic (ROC) curves to determine cut-points for appendiceal diameter and wall thickness for optimization of predictive power, and we calculated area under the curve (AUC) as a measure of test accuracy. Ninety-eight MRI examinations were performed in 97 subjects. Overall, MRI had a 94% sensitivity, 95% specificity, 91% positive predictive value and 97% negative predictive value. Optimal cut-points for appendiceal diameter and wall thickness were ≥7 mm and ≥2 mm, respectively. Independently, those cut-points produced sensitivities of 91% and 84% and specificities of 84% and 43%. Presence of intraluminal fluid (30/33) or localized periappendiceal fluid (32/33) showed a significant association with acute appendicitis (Pappendicitis when multiple diagnostic criteria are considered in aggregate. Individual diagnostic criteria including optimized cut-points of ≥7 mm for diameter and ≥2 mm for wall thickness demonstrate high sensitivities but relatively low specificities. Nonvisualization of the appendix favors a negative diagnosis.

Effects of sorghum wet distillers grains plus solubles in steam-flaked corn-based finishing diets on steer performance, carcass characteristics, and digestibility characteristics

Science.gov (United States)

Two studies were conducted to evaluate the effects of sorghum wet distillers grains (SWDGS) in finishing diets on steer performance, carcass characteristics, and nutrient digestibility. In Exp. 1, 240 steers (initial BW = 379 +/-1 kg) were fed steam-flaked corn (SFC)-based diets with or without 25%...

Performance Characteristics of Hero's Turbine Using Hot Water as a Working Fluid

OpenAIRE

藤井, 照重; 太田, 淳一; 赤川, 浩爾; 中村, 登志; 浅野, 等

1990-01-01

From the view point of energy saving and the development of new energy resources,it is important to utilize geothermal resources and waste heat from factories. As one of the energy conversion expanders,there is a radial outflow reaction turbine(that is,Hero's turbine). Performance characteristics of Hero's turbine using subcooled hot water as a working fluid are clarified analytically and experimentally. It is found that:(a)there is an optimum rotational speed at which maximum turbine efficie...

Performance characteristics of mobile MOSFET dosimeter for kilovoltage X-rays used in image guided radiotherapy.

Science.gov (United States)

Kumar, A Sathish; Singh, I Rabi Raja; Sharma, S D; Ravindran, B Paul

2015-01-01

The main objective of this study was to investigate the characteristics of metal oxide semiconductor field effect transistor (MOSFET) dosimeter for kilovoltage (kV) X-ray beams in order to perform the in vivo dosimetry during image guidance in radiotherapy. The performance characteristics of high sensitivity MOSFET dosimeters were investigated for 80, 90, 100, 110, 120, and 125 kV X-ray beams used for imaging in radiotherapy. This study was performed using Clinac 2100 C/D medical electron linear accelerator with on-board imaging and kV cone beam computed tomography system. The characteristics studied in this work include energy dependence, angular dependence, and linearity. The X-ray beam outputs were measured as per American Association of Physicists in Medicine (AAPM) TG 61 recommendations using PTW parallel plate (PP) ionization chamber, which was calibrated in terms of air kerma (Nk) by the National Standard Laboratory. The MOSFET dosimeters were calibrated against the PP ionization chamber for all the kV X-ray beams and the calibration coefficient was found to be 0.11 cGy/mV with a standard deviation of about ±1%. The response of MOSFET was found to be energy independent for the kV X-ray energies used in this study. The response of the MOSFET dosimeter was also found independent of angle of incidence for the gantry angles in the range of 0° to 360° in-air as well as at 3 cm depth in tissue equivalent phantom.

Numerical study of influence of biofuels on the combustion characteristics and performance of aircraft engine system

International Nuclear Information System (INIS)

Zhou, Li; Liu, Zeng-wen; Wang, Zhan-xue

2015-01-01

The atomization and combustion flowfield of the combustion chamber with swirl-nozzle were simulated using different biofuels; the thermodynamic cycle of the aircraft engine system were also analyzed, influences of biofuels on the combustion characteristics and performance of aircraft engine system were explored. Results show that viscosity and caloric value are key factors affecting the atomization and combustion characteristics of biofuels, and then dominate the distribution of the temperature and NO concentration. Due to the characteristic of low viscosity and low caloric value for biofuels adopted, the biofuels accumulate near the head of combustion chamber, and the corresponding NO emission is lower than that it has for conventional kerosene. When biofuels with low caloric value are used under the operation condition which is same as the condition for the conventional kerosene, lower turbine inlet temperature, lower thrust and higher specific fuel consumption would be achieved for the aircraft engine. - Highlights: • Influences of biofuels properties on combustion characteristic are explored. • Effects of biofuels on cycle parameters of aircraft engine are discussed. • Viscosity and caloric value are key factors affecting combustion of biofuels. • NO emission becomes lower when biofuels with low caloric value is adopted. • The performance of aircraft engine becomes worse for biofuels with low caloric value.

The gender gap reloaded: are school characteristics linked to labor market performance?

Science.gov (United States)

Konstantopoulos, Spyros; Constant, Amelie

2008-06-01

This study examines the wage gender gap of young adults in the 1970s, 1980s, and 2000 in the US. Using quantile regression we estimate the gender gap across the entire wage distribution. We also study the importance of high school characteristics in predicting future labor market performance. We conduct analyses for three major racial/ethnic groups in the US: Whites, Blacks, and Hispanics, employing data from two rich longitudinal studies: NLS and NELS. Our results indicate that while some school characteristics are positive and significant predictors of future wages for Whites, they are less so for the two minority groups. We find significant wage gender disparities favoring men across all three surveys in the 1970s, 1980s, and 2000. The wage gender gap is more pronounced in higher paid jobs (90th quantile) for all groups, indicating the presence of a persistent and alarming "glass ceiling."

Passive performance monitoring and traffic characteristics on the SLAC internet border

International Nuclear Information System (INIS)

Logg, C.; Cottrell, L.

2001-01-01

Understanding how the Internet is used by HEP is critical to optimizing the performance of the inter-lab computing environment. Typically use requirements have been defined by discussions between collaborators. However, later analysis of the actual traffic has show this is often misunderstood and actual use is significantly different to that predicted. Passive monitoring of the real traffic provides insight into the true communications requirements and the performance of a large number of inter-communicating nodes. It may be useful in identifying performance problems that are due to factors other than Internet congestion, especially when compared to other methods such as active monitoring where traffic is generated specifically to measure its performance. Controlled active monitoring between dedicated servers often gives an indication of what can be achieved on a network. Passive monitoring of the real traffic gives a picture of the true performance. The authors will discuss the method and results of collecting and analyzing flows of data obtained from the SLAC Internet border. The insights this has brought to understanding the network will be reviewed and the benefit it can bring to engineering networks will be discussed

Transformational leadership and safety performance among nurses: the mediating role of knowledge-related job characteristics.

Science.gov (United States)

Lievens, Ilse; Vlerick, Peter

2014-03-01

To report the impact of transformational leadership on two dimensions of nurses' safety performance (i.e. safety compliance and safety participation) and to study the mediating role of knowledge-related job characteristics in this relationship. Safety performance refers to the behaviours that employees exhibit to adhere to safety guidelines and to promote health and safety at their workplace. Nurses' safety performance is a major challenge for healthcare settings, urging the need to identify the key determinants and psychological mechanisms that influence it. A cross-sectional survey study. The study was carried out in September 2010 in a large Belgian hospital. We used self-administered questionnaires; 152 nurses participated. The hypotheses were tested using hierarchical regression analyses. In line with our first hypothesis, the results show that transformational leadership exerted a significant positive impact on both dimensions of nurses' safety performance. This positive relation was mediated by knowledge-related job characteristics, supporting our second hypothesis. Head nurses' transformational leadership can enhance nurses' compliance with and participation in safety. Furthermore, transformational head nurses are able to influence the perception that their nurses have about the kind and amount of knowledge in their job, which can also lead to increases in both dimensions of nurses' safety performance. This study therefore demonstrates the key impact that transformational head nurses have, both directly and indirectly, on the safety performance of their nurses. © 2013 John Wiley & Sons Ltd.

Neuromuscular activity during bench press exercise performed with and without the preexhaustion method.

Science.gov (United States)

Brennecke, Allan; Guimarães, Thiago M; Leone, Ricardo; Cadarci, Mauro; Mochizuki, Luiz; Simão, Roberto; Amadio, Alberto Carlos; Serrão, Júlio C

2009-10-01

The purpose of the present study was to investigate the effects of exercise order on the tonic and phasic characteristics of upper-body muscle activity during bench press exercise in trained subjects. The preexhaustion method involves working a muscle or a muscle group combining a single-joint exercise immediately followed by a multi-joint exercise (e.g., flying exercise followed by bench press exercise). Twelve subjects performed 1 set of bench press exercises with and without the preexhaustion method following 2 protocols (P1-flying before bench press; P2-bench press). Both exercises were performed at a load of 10 repetition maximum (10RM). Electromyography (EMG) sampled at 1 kHz was recorded from the pectoralis major (PM), anterior deltoid (DA), and triceps brachii (TB). Kinematic data (60 Hz) were synchronized to define upward and downward phases of exercise. No significant (p > 0.05) changes were seen in tonic control of PM and DA muscles between P1 and P2. However, TB tonic aspect of neurophysiologic behavior of motor units was significantly higher (p 0.05). The kinematic pattern of movement changed as a result of muscular weakness in P1. Angular velocity of the right shoulder performed during the upward phase of the bench press exercise was significantly slower (p < 0.05) during P1. Our results suggest that the strategies set by the central nervous system to provide the performance required by the exercise are held constant throughout the exercise, but the tonic aspects of the central drive are increased so as to adapt to the progressive occurrence of the neuromuscular fatigue. Changes in tonic control as a result of the muscular weakness and fatigue can cause changes in movement techniques. These changes may be related to limited ability to control mechanical loads and mechanical energy transmission to joints and passive structures.

Channel Characteristics and Transmission Performance for Various Channel Configurations at 60 GHz

Directory of Open Access Journals (Sweden)

Yang Haibing

2007-01-01

Full Text Available Extensive measurements are conducted in room environments at 60 GHz to analyze the channel characteristics for various channel configurations. Channel parameters retrieved from measurements are presented and analyzed based on generic channel models. Particularly, a simple single-cluster model is applied for the parameter retrieval and performance evaluation. By this model, power delay profiles are simply described by a -factor, a root-mean-squared delay spread, and a shape parameter. The considered channels are configured with the combination of omnidirectional, fan-beam, and pencil-beam antennas at transmitter and receiver sides. Both line-of-sight (LOS and non-LOS (NLOS channels are considered. Further, to evaluate the transmission performance, we analyze the link budget in the considered environments, then design and simulate an OFDM system with a data rate of 2 Gbps to compare the bit-error-rate (BER performance by using the measured and modeled channels. Both coded and uncoded OFDM systems are simulated. It is observed that the BER performance agrees well for the measured and modeled channels. In addition, directive configurations can provide sufficient link margins and BER performance for high data rate communications. To increase the coverage and performance in the NLOS area, it is preferable to apply directive antennas.

Channel Characteristics and Transmission Performance for Various Channel Configurations at 60 GHz

Directory of Open Access Journals (Sweden)

Haibing Yang

2007-05-01

Full Text Available Extensive measurements are conducted in room environments at 60 GHz to analyze the channel characteristics for various channel configurations. Channel parameters retrieved from measurements are presented and analyzed based on generic channel models. Particularly, a simple single-cluster model is applied for the parameter retrieval and performance evaluation. By this model, power delay profiles are simply described by a K-factor, a root-mean-squared delay spread, and a shape parameter. The considered channels are configured with the combination of omnidirectional, fan-beam, and pencil-beam antennas at transmitter and receiver sides. Both line-of-sight (LOS and non-LOS (NLOS channels are considered. Further, to evaluate the transmission performance, we analyze the link budget in the considered environments, then design and simulate an OFDM system with a data rate of 2 Gbps to compare the bit-error-rate (BER performance by using the measured and modeled channels. Both coded and uncoded OFDM systems are simulated. It is observed that the BER performance agrees well for the measured and modeled channels. In addition, directive configurations can provide sufficient link margins and BER performance for high data rate communications. To increase the coverage and performance in the NLOS area, it is preferable to apply directive antennas.

Effects of cooking methods and temperatures on nutritional and quality characteristics of anchovy (Engraulis encrasicholus).

Science.gov (United States)

Uran, Harun; Gokoglu, Nalan

2014-04-01

The aim of this study was to determine the nutritional and quality characteristics of anchovy after cooking. The fish were cooked by different methods (frying, baking and grilling) at two different temperatures (160 °C, 180 °C). Crude ash, crude protein and crude fat contents of cooked fish increased due to rise in dry matter contents. While cooking methods affected mineral content of anchovy, cooking temperature did not affect. The highest values of monounsaturated fatty acids were found in baked samples. Polyunsaturated fatty acids in baked samples were also high and similar in fried samples. Fried samples, which were the most preferred, lost its nutritional characteristics more than baked and grilled samples. Grilled and baked fish samples can be recommended for healthy consumption. However, grilled fish samples had hard texture due to more moisture loss than other methods. Therefore, it is concluded that baking is the best cooking method for anchovy.

Manufacturing methods and magnetic characteristics of magnetic wood

International Nuclear Information System (INIS)

Oka, H.; Hojo, A.; Osada, H.; Namizaki, Y.; Taniuchi, H.

2004-01-01

The relationship between wood construction and DC magnetic characteristics for three types of magnetic wood was experimentally investigated. The results show that the magnetic characteristics of each type of magnetic wood are dependent on the magnetic materials, the density of the magnetic material and the construction of the wood. Furthermore, it was determined that the relationship between the fiber direction and the magnetic path direction of the magnetic wood influenced the wood's magnetic characteristics

A Longitudinal Examination of The Impact of Founding Owner Operator Characteristics on Nascent Venture Performance: Evidence from the Kauffman Firm Survey

Directory of Open Access Journals (Sweden)

Augustine Y. Dzathor

2013-07-01

Full Text Available This study attempts to revive and clarify the debate on ‘the entrepreneurial man’. We longitudinally examined the effects of seven founding-owner-operator characteristics (prior industry experience, level of formal education, age, gender, ethnicity and time committed to business operations on nascent venture performance. Our results indicate that owner work experience, level of education and hours worked in the business have significant effect on nascent venture performance, while inadequate owner reputation and luck of ethnic social capital may negatively affect nascent venture performance. Our findings also suggest that characteristic of the ‘entrepreneurial man’ are dynamic and leans towards a temporal contingency model. Different entrepreneur characteristics seem to assume prominence in firm performance at different times in a nascent venture’s life trajectory.

Associations between Otolaryngology Applicant Characteristics and Future Performance in Residency or Practice: A Systematic Review.