Final Performance Evaluation Research Articles

Multiple Linear Regression Models for Predicting Nonpoint-Source Pollutant Discharge from a Highland Agricultural Region

Sediment runoff from dense highland field areas greatly affects the quality of downstream lakes and drinking water sources. In this study, multiple linear regression (MLR) models were built to predict diffuse pollutant discharge using the environmental parameters of a basin. Explanatory variables that influence the sediment and pollutant discharge can be identified with the model, and such research could play an important role in limiting sediment erosion in the dense highland field area. Pollutant load per event, event mean concentration (EMC), and pollutant load per area were estimated from stormwater survey data from the Lake Soyang basin. During the wet season, heavy rains cause large amounts of suspended sediment and the occurrence of such rains is increasing due to climate change. The explanatory variables used in the MLR models are the percentage of fields, subbasin area, and mean slope of subbasin as topographic parameters, and the number of preceding dry days, rainfall intensity, rainfall depth, and rainfall duration as rainfall parameters. In the MLR modeling process, four types of regression equations with and without log transformation of the explanatory and response variables were examined to identify the best performing regression model. The performance of the MLR models was evaluated using the coefficient of determination (R2), root mean square error (RMSE), coefficient of variation of the root mean square error (CV(RMSE)), the ratio of the RMSE to the standard deviation of the observed data (RSR) and the Nash–Sutcliffe model efficiency (NSE). The performance of the MLR models of pollutant load except total nitrogen (TN) was good under the condition of RSR, and satisfactory for the NSE and R2. In the EMC and load/area models, the performance for suspended solids (SS) and total phosphorus (TP) was good for the RSR, and satisfactory for the NSE and R2. The standardized coefficients for the models were analyzed to identify the influential explanatory variables in the models. In the final performance evaluation, the results of jackknife validation indicate that the MLR models are robust.

Balanced scorecard-based performance evaluation of Chinese county hospitals in underdeveloped areas.

ObjectiveSince the Guangxi government implemented public county hospital reform in 2009, there have been no studies of county hospitals in this underdeveloped area of China. This study aimed to establish an evaluation indicator system for Guangxi county hospitals and to generate recommendations for hospital development and policymaking.MethodsA performance evaluation indicator system was developed based on balanced scorecard theory. Opinions were elicited from 25 experts from administrative units, universities and hospitals and the Delphi method was used to modify the performance indicators. The indicator system and the Topsis method were used to evaluate the performance of five county hospitals randomly selected from the same batch of 2015 Guangxi reform pilots.ResultsThere were 4 first-level indicators, 9 second-level indicators and 36 third-level indicators in the final performance evaluation indicator system that showed good consistency, validity and reliability. The performance rank of the hospitals was B > E > A > C > D.ConclusionsThe performance evaluation indicator system established using the balanced scorecard is practical and scientific. Analysis of the results based on this indicator system identified several factors affecting hospital performance, such as resource utilisation efficiency, medical service price, personnel structure and doctor–patient relationships.

Effectiveness of a multicenter training programme to teach point-of-care vascular ultrasound for the detection of peripheral arterial disease in people with diabetes

BackgroundThe primary aim of this study was to evaluate the effectiveness of a training programme to teach a focused bedside ultrasound scan (PAD-scan; Podiatry Ankle Duplex Scan) for the detection of arterial disease in people with diabetes.MethodsFive podiatrists and one diabetologist across two hospitals were enrolled in a structured training programme consisting of a training course (1-day), supervised scanning (5-weeks), independent scanning (3-weeks) and a final evaluation of performance (1-day).Time, technical skills (Duplex Ultrasound Objective Structured Assessment of Technical Skills tool (DUOSATS); minimum score = 6, maximum score = 26) and accuracy (level of agreement with vascular scientist PAD-scan assessment) were assessed for every supervised scan and again for the final evaluation of performance.ResultsA total of 90 PAD-scans in 65 patients were performed during the supervised phase. Participants demonstrated significant improvements in median time (19 min(IQR 13.9–25.5) vs 9.3 min (IQR 7.3–10.5);p = 0.028) and DUOSATS scores (17.5 (IQR 16.8–21) vs 25 (IQR 24–25.3); p = 0.027). At the final evaluation, participants completed scans in 5.4 min (IQR 5.3–5.9), achieved full DUOSAT scores and perfect agreement with the vascular scientist.ConclusionA structured training programme, integrated into diabetic foot clinics, was effective in teaching the PAD-scan

Interview Scores Correlate with Fellow Microsurgical Skill and Performance

The interview process for surgical trainees aims to select those individuals who will perform best during training and have the greatest potential as future surgeons. The objective of this study was to evaluate the relationship between criteria assessed at interview, technical skills, and performance, for the first time, to optimize the selection process for a Microsurgery fellowship. Twenty microsurgery fellows in three consecutive annual cohorts at a single academic center were prospectively evaluated. At interview, subjects were scored for multiple standardized domains. At the start and at end of the fellowship, microsurgical technical skill was assessed both in the laboratory and operating room (OR) using a validated assessment tool. At the end of the fellowship, there was a final evaluation of performance. At the start, microsurgical skill significantly correlated with almost all domains evaluated at interview, most closely with prior plastic surgery training experience. At the end of the fellowship, skill level improved in all trainees, with the greatest improvement made by the lowest ranked and skilled trainees. The highest ranked trainees, however, made the greatest improvement in speed. The results of this study, for the first time, validate the current interview process to correctly select the highest performing and most skilled candidates and support the effectiveness of a 1-year microsurgical fellowship in improving microsurgical skill in all trainees, irrespective of their initial ability. The importance of valuing the relative quality of prior training and experience at selection is also highlighted.

A Novel Steering System for a Space-Saving 4WS4WD Electric Vehicle: Design, Modeling, and Road Tests

In this paper, we present a steering system for a space-saving four-wheel steering and four-wheel drive (4WS4WD) electric vehicle (EV) with higher maneuverability and flexibility. The proposed system consists of three main parts, namely, an improved two-front-wheel steering (2FWS) mechanism, an omnidirectional independent steering (OIS) mechanism integrated with steer-by-wire, and a control strategy for the space-saving steering system of an EV. First, the 2FWS mechanism of the proposed 4WS4WD EV is designed to control the front wheels via the redesigned steering system when the vehicle is traveling at high speeds. Second, a retrofitted OIS mechanism is proposed to achieve an angle range of $-\!\text{35}^{\circ}\sim+\text{90}^{\circ}$ , which is a solid basis for zero radius turning (ZRT) and lateral parking (LP) motion. The driver can control the OIS to turn the four wheels independently, which is assisted by steer-by-wire technologies. Finally, the control strategy for the space-saving steering system of the EV is redefined for the integrated 2FWS and OIS, which can easily handle the EV for high-speed driving or high-maneuverability turning, such as ZRT and LP motion. This system was field tested on a homemade 4WS4WD EV, and the final system simulation and performance evaluation demonstrated the validity of the proposed steering system for the space-saving 4WS4WD EV.

Abstract: Trainee Selection and the Correlation between Cognitive and Technical Skill Evaluation

INTRODUCTION: The selection process for surgical trainees aims to identify those who will perform best during training and have the greatest potential as future surgeons. Better understanding the predictive relationship between interview performance, level of technical skill, and performance during training will allow optimization of the interview and evaluation process to identify the best candidates.1–3 MATERIALS AND METHODS: Three annual cohorts of Reconstructive Microsurgery fellows at the Department of Plastic Surgery at the University of Texas MD Anderson Cancer Center, comprising 20 trainees, were included in the study. At interview, subjects were rated using seven criteria, as well as given a score for overall impression. At the start and end of the fellowship, microsurgical technical skill was assessed both in the OR and laboratory using a validated tool. At the end of the fellowship there was a final evaluation of performance using criteria adapted from the six Accreditation Council for Graduate Medical Education (ACGME) core competencies. Scores at interview, technical skill assessment, and final evaluation scores were all compared in multiple ways to determine associations and predictive factors. RESULTS: Microsurgical skill assessment in the OR at the start of training correlated with all domains evaluated at interview, most closely with Plastic Surgery Training Experience. Microsurgical skill assessment in the OR at the end of training also correlated with scores on the majority of final assessment criteria based on ACGME core competencies, with the highest correlations with Patient Care and Medical Knowledge. Assessment of microsurgical skill in the laboratory at the start of the fellowship did not improve the predictive relationship between interview scores and ACGME core competency evaluations. CONCLUSION: Microsurgical technical skill in the OR tracked with all domains evaluated at interview, and also with the majority of ACGME core competency evaluations. These results validate the use of the current selection process in choosing candidates with the highest level of both cognitive and technical skill, and also support the effectiveness of the one-year microsurgical fellowship at improving microsurgical skill in all trainees. DISCLOSURE/FINANCIAL SUPPORT:None of the authors has a financial interest in any of the products, devices, or drugs mentioned in this manuscript. REFERENCES: 1. Selber JC, Chang EI, Liu J, Suami H, Adelman DM, Garvey P, Hanasono MM, Butler CE. Tracking the learning curve in microsurgical skill acquisition. Plast Reconstr Surg. 2012;130:550. 2. Selber JC, Tong W, Koshy J, Ibrahim A, Liu J, Butler C. Correlation between Trainee Candidate Selection Criteria and Subsequent Performance. J Am Coll Surg. 2014; 219:951–7. 3. Alrasheed T, Liu J, Hanasono MM, Butler CE, Selber JC. Robotic microsurgery: validating an assessment tool and plotting the learning curve. Plast Reconstr Surg. 2014;134:794–803.

A Novel Vehicle Reversing Speed Control Based on Obstacle Detection and Sparse Representation

In this paper we present a vehicle safety method for reversing speed control based on obstacle detection and sparse representation. The proposed system consists of three main steps, namely, binocular camera obstacle detection and segmentation, obstacle tracking and recognition, and vehicle reversing speed control algorithm. First of all, a binocular camera system is used to detect obstacles as a vehicle is reversing. Using disparity computation and triangulation, we can get all objects' distance information in the rear of a vehicle. Second, the framework of particle filter and sparse representation are used to track and identify the main obstacles such as human or animal bodies, vehicles, or any other objects. Finally, the vehicle reversing speed control algorithm, which controls the electronic throttle opening and automatic braking prior to collisions, makes the reversing control safer and more reliable. This system has been field tested on a Dodge sport utility vehicle by which the final performance evaluation demonstrates the validity of the proposed vehicle reversing speed control.

Multi-fidelity optimization strategy for the industrial aerodynamic design of helicopter rotor blades

The industrial aerodynamic design of helicopter rotor blades needs to consider simultaneously the two typical flight conditions of hover and forward flight. In the present work this multi-objective design problem is tackled using a genetic algorithm, coupled to rotor performance simulation tools. The turn-around time of an optimization loop is acceptable in an industrial design loop when using low-cost, low-fidelity tools such as the comprehensive rotorcraft code HOST, but becomes excessively high when employing high-fidelity models like CFD methods. To incorporate high-fidelity models into the optimization loop while maintaining a moderate computational cost, a Multi-Fidelity Optimization (MFO) strategy is proposed: as a preliminary step, a HOST-based genetic algorithm optimization is used to reduce the parameter space and select a set of blade geometries used to initialize the high-fidelity stage. Secondly, the selected blades are re-evaluated by CFD and used to construct a high-fidelity surrogate model. Finally, a Surrogate Based Optimization (SBO) is carried out and the Pareto optimal individuals according to the SBO are recomputed by CFD for final performance evaluation. The proposed strategy is validated step by step. It is shown that an industrially acceptable number of CFD-simulations is sufficient to obtain blade designs with significantly higher performances than the baseline and SBO results issued from a standard Latin-Hypercube-Sampling initialization. The proposed MFO strategy represents an efficient method for the simultaneous optimization of rotor blade geometries in hover and forward flight.

Final Clarifier Performance Evaluation and Capacity Assessment at the City of Atlanta’s South River Water Reclamation Center

Final Clarifier Performance Evaluation and Capacity Assessment at the City of Atlanta’s South River Water Reclamation Center

Naturally-Forced Slug Flow Expander for Application in a Waste-Heat Recovery Cycle

This paper investigates a slug-flow expander (SFE) for conversion of high-pressure gas/vapor into kinetic energy of liquid slugs. The energy transfer from high-pressure to kinetic energy is quantified using thrust plate measurements. Non-dimensional thrust data is used to quantify performance by normalizing measured thrust by thrust for the same water flow rate at zero air flow rate. A total of 13 expander configurations are investigated and geometries with the shortest cavity length and the smallest exit diameter are found to result in the largest non-dimensional thrust increase. Results show that thrust augmentation increases with the initiation of slug flow in the SFE. The analysis performed on the normalized thrust readings suggested that as the water and air flow were increased to critical conditions, the liquid slugs produced by the SFE augmented the thrust measurements. The final performance evaluation was based on linear regression of the normalized thrust measurements where slug flow was generated for each SFE architecture. Greater magnitudes of the slope from the linear regression indicated the propensity of the SFE to augment thrust. This analysis confirmed that for the SFE configurations over the range of values investigated, the SFE increased thrust up to three times its original value at no air flow. Given the inherent multiphase nature of the slug-flow expander, application to systems involving expansion of wetting fluids (water as part of a waste-heat recovery system) or air with water droplet formation (as part of a compressed-air energy storage system) could be considered.

Assessing Competence for Reentry

Assessing Competence for Reentry

Disaster and exercise performance information collection tool: Capturing observations in four minutes or less

The objectives of the work described in this paper were to: (a) identify existing gaps in data collection, processing and dissemination across all types of emergencies; (b) build a tool that permits documentation, manipulation and propagation of relevant observations in emergency preparedness exercises or real-world incidents to inform critical decision makers in real time and to facilitate the elaboration of lessons learned, best practices and pioneering strategies for the management of future disasters; (c) validate the efficacy of the tool for collecting, processing and disseminating disaster-related information, through its integration in a series of exercises. The disaster and exercise performance information collection tool (DEPICT) was developed to address needs identified via the analysis of survey responses provided by representatives of military and civilian organisations with disaster response experience. Consensus discussions were held to identify criteria and operational parameters for the tool. As the development of DEPICT progressed, feedback and recommendations for improvements were provided to the developers, who incorporated the recommendations in successive iterations, resulting in increased refinements of the tool. DEPICT was subsequently tested for feasibility through operations-based exercises centred on catastrophic earthquakes in three diverse geographic locations of the USA. Feedback regarding DEPICT’s functional performance during the exercises was used to inform further refinements to the program. The authors developed the DEPICT software on a PHP platform to accomplish two goals: (1) offer a core that supports user interaction and data management requirements (eg data capture, transmission and storage); (2) present a user-friendly interface with a shallow learning curve to facilitate a better user experience. DEPICT is a user-friendly, web-based application that is accessible through various mobile web-enabled devices. The application allows responders, emergency planners and exercise evaluators to capture written and photographic field observations, on average, in four minutes or less per observation. These observations may be further processed or formatted offsite by analysts, prior to their submission for final exercise performance evaluation. Ultimately, the data form the basis of after-action reports, which, in turn, underpin future decision making and improved disaster response practices.

유리섬유강화콘크리트를 이용한 자연형 경관석의 성능기준 연구

This study aims to establish the performance standard for natural type landscape stone GFRC. The required performance such as material performance, structural safety performance, durability performance, and landscape performance were selected through an examination of domestic and overseas performance related references and examples, and through the questionnaires obtained from 40 experts, and the verified items and performance standards were proposed. Among the required performances, the material performance(glass fiber content, air-dried gravity), structural safety performance(flexural strength, compressive strength), durability performance(crack, corrosion resistance), and landscape performance(texture, efflorescence) were selected through the questionnaires obtained from the experts. In the case of material performance and structural safety performance with the corresponding standards that existed, final performance evaluation standard was proposed by conducting a test and comparing it with the existing standard sample, and in the case of durability performance and landscape performance on which standard does not existed, they were verified by measuring directly through field examination of formative landscape items such as artificial waterfall etc. In this study, performance standard for the material on natural type landscaping rocks GFRC and items which can be evaluated after construction such as material performance, structural safety performance, durability performance, landscape performance, and so forth were proposed, however, follow up study for pro-environmental and ecological performance standard which were recently gaining force would be required through a continuous monitoring for the construction samples afterwards.

Quantitative structure/eluent–retention relationships in reversed-phase high-performance liquid chromatography based on the solvatochromic method

Some predictive approaches aimed at modelling the combined effect of solute molecular structure and mobile phase composition on retention in reversed-phase high-performance chromatography (RP-HPLC) have been developed in the literature. These models are established for a given binary eluent (normally acetonitrile-water or methanol-water) by non-linear (curvilinear or artificial neural network) regression assuming as the mobile phase descriptor the volume fraction φ of the organic modifier. In the present investigation, we propose a model applicable simultaneously to acetonitrile-water and methanol-water eluents. To this end, the Kamlet-Taft solvatochromic descriptors of the eluent and the solvatochromic descriptors of the analytes are considered as the input variables of a multi-layer artificial neural network (ANN) providing the solute retention as the response. This approach is applied to a set of 31 molecules analyzed with five different columns in the φ range 20-70 % at 10 % steps for both acetonitrile- and methanol-containing mobile phases. For each column, an ANN-based model is built using retention data of 25 molecules selected by the Kennard-Stones algorithm while retention data of the unselected six solutes are considered in the final evaluation of predictive performance of the trained network. To test cross-eluent prediction, the network optimized for a given column was successively trained with data collected in eight out of 12 eluents and applied to deduce retention in the four remaining mobile phases. The results reveal that RP-HPLC behavior of external solutes is quite accurately modelled in the whole explored composition range of acetonitrile- and methanol-water mobile phases. Moreover, the model exhibits a promising capability of deducing retention of external solutes even in unknown eluents.

Sustaining iterative game playing processes in DGBL: The relationship between motivational processing and outcome processing

Digital game-based learning (DGBL) has become a viable instructional option in recent years due to its support of learning motivation. Recent studies have mostly focused on identifying motivational factors in digital games (e.g., curiosity, rules, control) that support intrinsic motivation. These findings, however, are limited in two fronts. First, they did not depict the interactive nature of the motivational processing in DGBL. Second, they excluded the outcome processing (learners’ final effort versus performance evaluation) as a possible motivation component to sustain the iterative game playing cycle. To address these problems, situated in the integrative theory of Motivation, Volition, and Performance (MVP), this study examined the relationship between motivational processing and outcome processing in an online instructional game. The study surveyed 264 undergraduate students after playing the Trade Ruler online game. Based on the data collected by ARCS-based Instructional Materials Motivational Survey (IMMS), a regression analysis revealed a significant model between motivational processing (attention, relevance, and confidence) and the outcome processing (satisfaction). The finding preliminarily suggests that both motivational processing and outcome processing need to be considered when designing DGBL. Furthermore, the finding implies a potential relationship between intrinsic motives and extrinsic rewards in DGBL.

Maximizing area under ROC curve for biometric scores fusion

The receiver operating characteristics (ROC) curve has been extensively used for performance evaluation in multimodal biometrics fusion. However, the processes of fusion classifier design and the final ROC performance evaluation are usually conducted separately. This has been inevitable because the ROC, when taken from the error counting point of view, does not have a well-posed structure linking to the fusion classifier of interest. In this work, we propose to optimize the ROC performance directly according to the fusion classifier design. The area under the ROC curve (AUC) will be used as the optimization objective since it provides a good representation of the ROC performance. Due to the piecewise cumulative structure of the AUC, a smooth approximate formulation is proposed. This enables a direct optimization of the AUC with respect to the classifier parameters. When a fusion classifier has linear parameters, computation of the solution to optimize a quadratic AUC approximation is surprisingly simple and yet effective. Our empirical experiments on biometrics fusion show strong evidences regarding the potential of the proposed method.

HAIRVEQ 2006: Evolution of laboratories’ performance after different educational actions

HAIRVEQ is a proficiency testing program for hair analysis of illicit drugs organized by the Istituto Superiore di Sanità (Rome, Italy) and the Institut Municipal d’Investigació Mèdica (Barcelona, Spain). The aim of the three exercises performed in 2006 was the evaluation of 32 laboratories’ performance when analyzing the same hair sample containing opiates, cocaine and methadone, after carrying out some specific educational interventions. In the first round, the sample was sent to be analyzed following laboratory routine methodology. In the second round, standard operating procedures (SOP) for hair testing including sample preparation, method validation and qualitative and quantitative data evaluation, and an open hair sample for SOP training were also sent together with other hair samples including the one used for performance evaluation. After the second round, a workshop was held with participant laboratories to discuss methodological issues and interpretation of obtained results. An additional amount of open samples was distributed to the laboratories for implementing the SOPs. In the third round, the same unknown sample containing opiates, cocaine and methadone was resent for the final evaluation of laboratory performance. In the first round, 11 incorrect qualitative results (10 false negative and 1 false positive) were reported by seven laboratories (22%), in the second round, a reduction in the number of incorrect results was observed (4 false negatives and 1 false positive were reported by four laboratories, 13%) and in the third round, 5 false positives and 5 false negatives were reported by seven laboratories (22%). Concerning quantitative results, the scatter was similar between the three rounds and similar to the ones reported by other proficiency tests in hair analysis. More educational actions should be addressed to a group of laboratories, which did not yet show satisfying qualitative and quantitative results.

댐 안전성 평가를 위한 여수로 피어부의 정적 거동 분석

Seismic performance evaluation for dam safety evaluation has been continually conducted. However the behavior analysis for the spillway pier which is known as the weak point of dam is seldom reported. Therefore, this study performed the static loading tests for a prototype structures as elementary tests for the final seismic performance evaluation of dam safety. The prototype of pier structure has 1/20 scale and it adopts to strength model. And cracking loads and ultimate loads of real structures are calculated through numerical analysis using commercial FEM program (ABAQUS). The results of this study show some difference between the results of prototype tests and the results of numerical analysis. Also, the ultimate and cracking loads can be estimated through the prototype loading test and numerical analysis.

An analysis of searchers' perceptions of sponsored and non‐sponsored links using nested design

AbstractThis paper examines the effects of sponsored links' reputation. We pursued this study through a mature design of experiment method – the nested design – in order to investigate this fast growing segment of online advertising. In this study, we firstly analyze the adaptability of the nested design to find out whether the reputation of sponsored links will bias searchers. We then carefully contrived a user study to investigate this phenomenon. We used 56 participants engaged in six ecommerce Web searching tasks. The tasks were extracted from the transaction log of a Web search engine so that they could represent actual ecommerce searching information needs. We controlled the study by switching non‐sponsored and sponsored links on half of the tasks for each participant. By doing this, we could use the nested design statistical method to detect the impact of the sponsored links' reputation on the final evaluations of these results. During the study, we collected 2,435 interactions with links from search engine results page and 961 utterance evaluations of these links. The results indicate that the reputation or the location of the sponsored links will show strong significance on the final evaluation of the search engine performance. We give some perspectives and discussion which could benefit search engine providers to improve their services.

Combined Laboratory/Field Study on the Use of Nitrate for in Situ Bioremediation of a Fuel-Contaminated Aquifer

A pilot demonstration project was conducted at Eglin Air Force Base, FL, to compare the extent of bioremediation of a fuel-contaminated aquifer using sprinkler application with and without nitrate addition on two adjacent 30 m × 30 m cells. Target compound groups included both BTEXTMB (benzene, toluene, ethylbenzene, xylenes, and trimethylbenzenes) and the JP-4 jet fuel. Bioremediation performance was monitored through the use of groundwater quality measurements as well as periodic core analyses. Operation began April 1994, and an interim performance evaluation was conducted August 1994. The final performance evaluation was conducted May 1995. Minimal remediation occurred during the first four months. Water quality analyses showed that the nitrate cell subsurface was actively denitrifying, but lysimeter samples indicated that much of the nitrate was consumed within the rhizosphere above the fuel-contaminated interval. A 9 m × 9 m plot inside each cell was therefore stripped of vegetative cover and covered with a weed barrier to enhance nitrate transfer into the subsurface. After an additional 8 months operation, lysimeter samples showed increased nitrate transfer to the contaminated interval beneath the nitrate cell stripped plot, and there was higher fractional removal of contaminant groups beneath the stripped plots as well. On the basis of core data, BTEXTMB was reduced by 66 ± 1% in both treatment cells, equivalent to a mass loss of 106 and 21 kg in the nitrate cell and control cell, respectively. Monitoring well data provided evidence of sulfate reduction in the control cell but not in the nitrate cell. In addition, post-test treatability studies using core material from both cells demonstrated removal of alkylbenzenes under denitrifying and iron-reducing conditions, with different profiles for each cell. One year after completion of the project, BTEXTMB reductions in downgradient monitoring wells remained consistent with the core data. Collective laboratory and field data indicated that contaminant reduction occurred as a result of anaerobic bioremediation as well as soil washing and that different anaerobic processes predominated in the control cell due to circulation of endogenous electron acceptors.