Proposed Performance Index Research Articles

Alternative methodology for assessing cracking resistance of hot mix asphalt mixtures with overlay tester

Several highway agencies have either implemented or considered implementing performance tests to predict the cracking potential of asphalt concrete (AC) mixes in the laboratory setting. One such test, the overlay tester (OT), simulates the opening and closing of the cracks induced by daily temperature variations and tensile strain generated by the traffic load. The variability of the OT results is expressed as a major concern in reliably characterising cracking potential of the AC mixes. A more fundamental analysis process and more mechanistic performance indicators were implemented that consider the two stages of the cracking mechanism (i.e. crack initiation and crack propagation). The repeatability of the proposed performance indices, critical fracture energy and crack progression rate, seems to be better than the current criterion based on the number of cycles to dissipate 93% of the initial maximum peak load. The proposed cracking methodology and associated preliminary failure limits seem to characterise and discriminate satisfactorily the cracking resistance of AC mixes. Given its promise in this study, the proposed OT test method is recommended as a routine test during the mix-design process of AC mixes to predict and screen their cracking susceptibility.

Systematic comparison of two-stage analytical rutting models of asphalt mixtures

The performance of 18 analytical models was investigated based on statistical analysis of R2, limiting deviation error, as well as their ability to predict long term rutting of AC-13 and AC-20 asphalt mixtures. An R2>95% on fitting could not guarantee well simulated initial rutting values or accurate long term rutting predictions. However, a model showing a maximum of 200 initial cycles exceeding a deviation error of 20%, could guarantee rutting curve fittings with R2>95%. The ability to accurately predict long term rutting was considered the best indicator of good models. Among the 18 models, only Theng – Lytton, Paute – 1, Paute – 2 and Monismith – 1 models satisfied the limiting values of the proposed performance indicators. Nonetheless, these same models required correction factors to accurately predict long term rutting when fitted to early age rutting results. Theng-Lytton model was considered the most reliable model, and a related rutting index was developed which could well be used for mixture design and optimisation.

GROUND OF BASIC ECONOMIC INDICATORS OF EFFECTIVENESS OF MACHINEBUILDING ENTERPRISES

The main objectives of the article are to determine the main economic indicators of the effectiveness of machinebuilding enterprises in the monitoring system. To optimize, you need to know what is wrong or ineffective, so it is necessary to measure various aspects of business processes that reflect the performance of the enterprise. To do this, use the monitoring system of economic performance indicators of the enterprise. So in the article existing approaches to evaluating business performance and results analysis using their validity are generalized. the criteria of evaluation of integral index of effectiveness of machine-building enterprise are certain, and also his components that is determined by basic business processes and business processes of development. The partial indicators of effectiveness are considered in the context of three-dimensional criterion format "cost - time - quality". The criteria for indicators of the individual components and the integral performance indicator based on typical Harrington scale intervals are defined and meet the following levels: high, sufficient, satisfactory, inadequate and critical level. Evaluating the effectiveness of the proposed methodological approach provides a basis for defining a list of existing problems and providing substantiated proposals for the implementation of corrective and / or preventive measures aimed at improving the company's performance. Using such an assessment will provide managers with the opportunity to receive regular analytical information to monitor the performance of the enterprise, assess the relevance of the company's current activities to strategic goals and prospects of development, timely response to organizational changes. Prospects for further research, we see in determining the ratio of proposed performance indicators to the traditional economic indicators of machine-building enterprises.

Anchorage performance of headed deformed bars in exterior beam-column joints under cyclic loading

The anchorage performance of headed deformed bars anchored in inter-story exterior beam-column joints under cyclic load was examined based on a test database with 118 test data. A proposed performance index based on the ACI 318 development length equation was used to evaluate the anchorage performance of the headed deformed bars of the specimens in the database. The results of the evaluation showed that the anchorage performance was positively correlated with the axial load, amount of joint transverse reinforcement parallel to the direction of applied shear, and head bearing area ratio, and was negatively correlated with the clear bar spacing and column moment ratio. Based on the evaluation, limits on design parameters (i.e., the minimum clear bar spacing, head bearing area ratio, concrete and steel strengths) were proposed. It was found that all the specimens in the test database showed satisfactory seismic performance if they satisfied the development length equation of the ACI 318 code and the proposed limits on design parameters.

Correlation of a new index with energy-based damage indices

The extent of damage to structures after an earthquake can be quantified by using damage indices in performance-based seismic design. Several damage indicators are discussed and evaluated for their applicability in seismic damage evaluation. The correlation between a new performance index proposed previously by some of the authors and energy-based damage indicators is studied numerically. To this aim, a six-storey reinforced-concrete frame structure is designed according to current seismic codes. Pushover analyses with three load patterns, as well as dynamic time histories for typical ground motions scaled for varying intensities, are performed on the structure. The grade of interdependency between the proposed performance index and the energy-based damage indices is quantified using a correlation coefficient. The results show that the proposed performance index exhibits high correlation with the energy-based damage indicators; some are almost perfectly correlated. What is more, this index is proved to be not sensitive to the lateral load patterns of pushover analysis. Therefore, it is recommended that the proposed performance index can be used as a substitute for energy-based damage measures to assess the seismic performance of structures.

Margin-Based Framework for Online Contingency Selection in Unbalanced Networks

A framework for performing fast online contingency selection in unbalanced power systems is presented in this paper. Selection methods are typically based on the principle of identifying the effect of contingencies on multiple normalized performance indices and ranking them using the results. Presently used performance indices are highly nonlinear and they are known to mask the effects of single contingencies leading to misclassifications. In this paper, we propose two new methods, one relying on margin-based performance indices and another based on state sensitivity. New performance indices are proposed based on margins of 1) circuit loading, 2) bus voltages, and 3) reactive power. In addition, a state sensitivity method is proposed which estimates a system's post contingency operating state via a single iteration of the quadratized power flow model and provides estimates of post contingency line loading, bus voltages, and reactive power levels. Numerical experiments on a three phase version of the IEEE Reliability Test System show that the proposed performance indices yield more accurate results, at a computational cost comparable to a single power flow iteration. The state sensitivity method is more accurate in identifying critical contingencies but its computational cost is higher. The method has been also demonstrated in the larger PEGASE systems.

Kalman Filter With Dynamical Setting of Optimal Process Noise Covariance

We propose a dynamical way to set the process error covariance matrix (Q) for a constant velocity (CV) model Kalman filter. We are able to achieve the best possible solution for the estimated state, in the sense of forecast error, while significantly reducing the convergence time at no significant computational cost. No assumptions regarding the statistical nature of the observed process are made and no prior knowledge of the system is required. To achieve this, we adopt a recently proposed performance index for the Kalman filter, we map the best Q for an ample range of model deviations (accelerations) and dynamically set the best possible Q for the CV filter by identifying the average acceleration of the measured signal online. We demonstrate our scheme ability by filtering simulated trajectories with low, medium, and high signal-to-noise ratios. We also track a real erratic target and compare our filter prediction with the best possible a posteriori CV filter.

Performance Assessment of Cross-Directional Control for Paper Machines

The minimum variance controller has been extensively used as a benchmark in the performance assessment of both univariate and multivariate control loops when time delay is the fundamental performance limitation. In this paper, the spatial and temporal performance limitations in the cross-directional (CD) control of paper machines are analyzed. The idea of minimum variance benchmarking is extended to the CD process based on these performance limitations. Based on an industrial CD controller, a user-specified benchmark, which is more practical and less aggressive, is also proposed. In addition, several related performance indices are proposed for the CD process based on both the minimum variance benchmark and the user-specified benchmark. Illustrative examples from a paper machine simulator and industrial data sets are provided to show the effectiveness of the proposed performance indices.

Maritime environmental performance indicators for urban waterways in Amsterdam

Owing to new regulations starting from 2025, all commercial canal boats have to comply to zero local emission standards in Amsterdam. It is therefore vital that a clear emission indicator is made available for vessels with a varying operational profile, such as canal boats. In this paper, it is argued that current indicators, such as the Energy Efficiency Design Index, are not suitable for these (passenger) vessels. This paper proposes environmental performance indicators that can quantify emissions, (non-dimensional) energy and fuel usage based on an operational profile set in the design phase. This profile includes part load operation and auxiliary consumers and it can compare new designed concepts with current baseline vessels based on the ‘benefit for society’ of different vessel types. In the proposed environmental performance indicators, several operational modes can be defined, in contrast with the currently proposed Energy Efficiency Design Index, which is a point index at 75% of installed power. To gauge not only local emissions but also global emissions, the environmental performance indicator methodology is used to determine a minimum efficiency from any power generation method. This minimum efficiency follows from a comparison between baseline vessels and concepts that are more energy efficient and emission friendly. The proposed environmental performance indicators were validated using measurements on typical propulsion configurations of canal boats in Amsterdam. Three full electric concepts were designed and compared with the measured baseline vessels. As full electric concepts do not have local emissions, the method of power generation must satisfy the requirement to have less global emissions than the mechanical baseline. Furthermore, an energy efficiency of at least 33% is calculated from a fossil-fuelled land-based power plant (including transport) to the boundary from quay to boat to be required for newly designed electric concepts to be more energy efficient than the mechanical baseline.

New performance indices for the optimization of controller gains of automatic generation control of an interconnected thermal power system

Abstract This paper proposes four new performance index (PI) criteria for the optimal tuning of controller gains of automatic generation control. The peak sum squared error (PSSE), peak sum time multiple squared error (PSTSE), peak sum absolute error (PSAE) and peak sum time multiple absolute error (PSTAE) are the new performance Index criteria which have been proposed against the existing criteria given as integral squared error (ISE), integral time multiple squared error (ITSE), integral absolute error (IAE) and integral time multiple absolute error (ITAE), respectively. To demonstrate the robustness of the proposed performance index criteria, the investigations are carried out for non-reheat as well as reheat interconnected thermal power system. Further, the dynamic performance of the proposed performance index criteria have been investigated over the continuous and discrete AGC systems. To firmly testify the superiority of the proposed criteria, discrete AGC system has been analyzed for the wide range of sampling periods. The study also reveals some new findings in discrete data automatic generation control system.

Performance indices and evaluation of algorithms in building energy efficient design optimization

Building energy efficient design optimization is an emerging technique that is increasingly being used to design buildings with better overall performance and a particular emphasis on energy efficiency. To achieve building energy efficient design optimization, algorithms are vital to generate new designs and thus drive the design optimization process. Therefore, the performance of algorithms is crucial to achieving effective energy efficient design techniques. This study evaluates algorithms used for building energy efficient design optimization. A set of performance indices, namely, stability, robustness, validity, speed, coverage, and locality, is proposed to evaluate the overall performance of algorithms. A benchmark building and a design optimization problem are also developed. Hooke–Jeeves algorithm, Multi-Objective Genetic Algorithm II, and Multi-Objective Particle Swarm Optimization algorithm are evaluated by using the proposed performance indices and benchmark design problem. Results indicate that no algorithm performs best in all six areas. Therefore, when facing an energy efficient design problem, the algorithm must be carefully selected based on the nature of the problem and the performance indices that matter the most.

Optimizing Tire Vertical Stiffness Based on Ride, Handling, Performance, and Fuel Consumption Criteria

Researchers mostly focus on the role of suspension system characteristics on vehicle dynamics. However tire characteristics are also influential on the vehicle dynamics behavior. In this paper, the effects of tire vertical stiffness on the ride, handling, accelerating/braking performance, and fuel consumption of a vehicle are analytically investigated. Furthermore, a method for determining the optimum vertical stiffness of tires is presented. For these purposes, first an appropriate mathematical criterion for the ride, handling, accelerating/braking performance, and fuel consumption is developed. Next, to achieve the optimum tire characteristic, a performance index, which contains all of the above-mentioned criteria, is defined and optimized. In the proposed performance index, the tire vertical stiffness is a design variable and its optimization provides a compromise among ride, handling, accelerating/braking performance, and fuel consumption of the vehicle. Last, the analytical optimization results are confirmed by performing precise numerical simulations.

Risk Analysis Using Earned Value

Control and feedback in complex and sensitive systems with different resources and properties in uncertainty conditions are one of the significant challenges for project managers. Therefore, in this paper an integrated model with quantitative and qualitative approach based on Earned value management and risk analysis methods proposed to decrease deviations in time and cost estimation at complete (EAC(t) & EAC). Using the proposed performance indexes based on risk scores obtained by non-parametric resampling technique, namely bootstrap, calculating more accurate estimations of final cost and duration at lower and upper band with various confidence levels will be possible. Finally, an illustrative case study presented demonstrating the proposed model can be efficiently applied through real case software projects.

Performance Index for Water Distribution Networks under Multiple Loading Conditions

AbstractPrevious studies have naturally related water distribution network performance to the ability to deliver sufficient pressure and flow. The present paper emphasizes that performance also depends on the efficiency of delivering these requirements. Accordingly, an efficiency-based performance index is proposed. It is the geometric average of four performance metrics: reliability, vulnerability, resilience, and connectivity. These are themselves based on the energy efficiency, hydraulic capacity, and structural ability of the system to deliver water under a range of conditions. The metrics are applied to two example networks and variations of these, enabling the assessment of their relevance, their sensitivity to system changes, and permitting a comparison to existing metrics. Variations represent different redundancy increasing strategies, recognized for improving performance. The proposed performance index generally follows a similar trend as the previous indices, increasing with network pressure. N...

Performance indices for quantitative measurement of R&D results in private construction companies

As the investment in Research and Development (R&D) projects is increasing in private construction companies in Korea, the necessity to evaluate the effects of the investment in terms of company's finance is growing. However, there has not been an applicable system to properly and quantitatively measure the result and effectiveness of R&D efforts in Korea. In order to evaluate R&D results, R&D performance indices and their monetarily performance are required. Therefore, the purpose of this study is to develop performance indices capable of measuring the R&D performance quantitatively in private construction companies. To accomplish this purpose, development direction of performance indices has been established, through the analysis on current R&D measurement standards in major Korean private construction companies and through carrying out questionnaire survey. The development of performance indices has been implemented through the applicability evaluation of public R&D performance indices, the analysis on evaluation criteria in major Korean private construction companies, and the analysis on actual data of R&D projects of a Korean private construction company. 20 Performance indices are proposed by 5×5 matrix with performance areas (such as productivity, knowledge accumulation, application, publication, and standardization) and R&D purposes (such as product development, construction process/method development, specification development, standardization development, and others). The effectiveness of proposed performance indices was verified to be appropriate for R&D projects in private construction companies in Korea, through questionnaire survey with evaluation criteria such as comparability, measurability and validity. The primary contribution of this study is to establish private R&D performance indices essential to convert the R&D efforts into monitory term. As a result, they can help company executives to make decision to invest on R&D based on the reliable quantitation of R&D outcome.

Automatic Parameter Setting Method for an Accurate Kalman Filter Tracker Using an Analytical Steady-State Performance Index

We present an automatic parameter setting method to achieve an accurate second-order Kalman filter tracker based on a steady-state performance index. First, we propose an efficient steady-state performance index that corresponds to the root-mean-square (rms) prediction error in tracking. We then derive an analytical relationship between the proposed performance index and the generalized error covariance matrix of the process noise, for which the automatic determination using the derived relationship is presented. The model calculated by the proposed method achieves better accuracy than the conventional empirical model of process noise. Numerical analysis and simulations demonstrate the effectiveness of the proposed method for targets with accelerating motion. The rms prediction error of the tracker designed by the proposed method is 63.8% of that with the conventional empirically selected model for a target accelerating at 10 m/s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .

Project time and cost estimate at completion based on non-parametric resampling with interval risk

Control and feedback in complex and sensitive systems with different resources and properties in uncertainty conditions are one of the significant challenges for project managers. Therefore, in this paper, an integrated model with quantitative and qualitative approach based on earned value management and risk analysis methods proposed to decrease deviations in time and cost estimation at complete (EAC(t) and EAC). Using the proposed performance indexes based on risk scores obtained by non-parametric resampling technique, namely bootstrap, calculating more accurate estimations of final cost and duration at lower and upper band with various confidence levels will be possible. Finally, an illustrative case study presented demonstrating the proposed model can be efficiently applied through real case software projects.

Performance indices for water network partitioning and sectorization

Water network partitioning in district metering areas, or sectorization, is an important process for improving water network management. It can help water utilities to implement active leakage control, conduct pressure management, and prevent network contamination. It is generally achieved by closing some network pipes, thus reducing pipe redundancy and affecting system performance. No systematic set of performance indices has been defined to evaluate a sectorization design and thus allow for a comparison of different possible sectorizations on a formal basis. In this paper, several performance indices for water network partitioning are proposed and tested using two real water supply systems: Parete in Italy and Matamoros in Mexico. Both systems' sectorizations were previously designed by a novel effective automatic technique recently developed by the authors. For both the original and sectorized networks, the proposed performance indices considered energy dissipated in the network, network resilience, pressure variation, fire-fighting capacity, water age, and mechanical redundancy. Network resilience appears to be the most representative index for the entire network, whereas pressure variation indices are more appropriate for describing individual districts. Except for fire-fighting capacity in one network, system performance did not appear to be affected significantly after sectorization.

Optimal Control for Unknown Discrete-Time Nonlinear Markov Jump Systems Using Adaptive Dynamic Programming

In this paper, we develop and analyze an optimal control method for a class of discrete-time nonlinear Markov jump systems (MJSs) with unknown system dynamics. Specifically, an identifier is established for the unknown systems to approximate system states, and an optimal control approach for nonlinear MJSs is developed to solve the Hamilton-Jacobi-Bellman equation based on the adaptive dynamic programming technique. We also develop detailed stability analysis of the control approach, including the convergence of the performance index function for nonlinear MJSs and the existence of the corresponding admissible control. Neural network techniques are used to approximate the proposed performance index function and the control law. To demonstrate the effectiveness of our approach, three simulation studies, one linear case, one nonlinear case, and one single link robot arm case, are used to validate the performance of the proposed optimal control method.

High Performance Reduced Order Models for Wind Turbines with Full-Scale Converters Applied on Grid Interconnection Studies

Wind power has achieved technological evolution, and Grid Code (GC) requirements forced wind industry consolidation in the last three decades. However, more studies are necessary to understand how the dynamics inherent in this energy source interact with the power system. Traditional energy production usually contains few high power unit generators; however, Wind Power Plants (WPPs) consist of dozens or hundreds of low-power units. Time domain simulations of WPPs may take too much time if detailed models are considered in such studies. This work discusses reduced order models used in interconnection studies of synchronous machines with full converter technology. The performance of all models is evaluated based on time domain simulations in the Simulink/MATLAB environment. A detailed model is described, and four reduced order models are compared using the performance index, Normalized Integral of Absolute Error (NIAE). Models are analyzed during wind speed variations and balanced voltage dip. During faults, WPPs must be able to supply reactive power to the grid, and this characteristic is analyzed. Using the proposed performance index, it is possible to conclude if a reduced order model is suitable to represent the WPPs dynamics on grid studies.