Performance Criteria Research Articles

Discrete heating of turbulent FSI in a vented lid-driven enclosure

Heat dissipation from a segmental heat source confined in a vented cavity with a moving lid is investigated numerically. The left wall is made flexible with an opening to force the cooling fluid with Rein. The fluid is discharged out from another opening located in the opposite right wall. The lid of the cavity is driven by a speed four times greater than the inlet velocity, ReLid = 4Rein. The κ -ε turbulent model together with the interaction of the fluid with the flexible wall (FSI) are solved numerically using the method of finite element. The impacts of Reynolds, Richardson Ri and Prandtl Pr numbers, elasticity of the flexible wall and the location of the inlet ports are scrutinized. It is found that the location of the inlet port and the Prandtl number play crucial roles in improving the overall performance. It is found that the lower position of the inlet port gives better performance than the higher position, where the performance criterion is 1.69 at Ri = 100. Results reveal that the lower Prandtl number (0.71) gives higher Nusselt number, where at Ri = 100, setting Pr at 0.71 the Nusselt number increases by 125% more than Pr = 6.5. It is concluded that the flexible wall either promotes the Nusselt number or alleviates the pressure drop.

A Survey on Maximum Ratio Combination: Applications, Evaluation and Future Directions

With the rapid development of wireless communications, the occupation of time and frequency resources becomes more crowded. The exploitation of space resources is necessary and the diversity combining techniques have substantial applications. Diversity combining achieves great diversity gains and improves the ability to combat multipath fading, among which the maximum ratio combining (MRC) performs as the optimal linear combining approach. However, MRC suffers from detrimental factors such as channel fading and no Gaussian noise in practical scenarios. In this paper, we focus on a comprehensive investigation of MRC. Starting from the MRC principle and system model, we summarize typical scenarios and analyze the channel fading statistics. For the influential factors, we further review related literature on channel correlation, cochannel interference (CCI) and impulsive noise. Major performance criteria and performance bounds are derived and compared. MRC confronts new developing challenges and the major development directions are reviewed. The paper finally discusses recent works and open problems for MRC applications and development. Emerging techniques such as artificial intelligence provide novel solutions for MRC performance improvements. The paper aims to present a summarized insight to assist readers in clarifying the analyzed methodology of MRC, so as to motivate new technology integration and extensive applications of advanced communication systems.

Economic/sustainability optimization/analysis of an environmentally friendly trigeneration biomass gasification system using advanced machine learning

The present research presents an innovative thermal integration model for a biomass-based power plant to generate power, coolant, and liquefied hydrogen. This integrated arrangement comprises biomass gasification, gas turbine cycle, organic flash-bi-evaporator refrigeration cycle, multi-effect desalination, solid oxide electrolyzer, and Claude cycle. The selection of an eco-friendly fluid for the electricity-cooling production cycle is conduced relying on a comparative analysis. The subsequent examination evaluates the economic-sustainability performance criteria through sensitivity and contour analyses. The comparative assessment identifies R1234ze(Z) as the most suitable working fluid. Four objective functions are scrutinized, and two optimization scenarios are devised based on a machine learning approach using artificial neural networks and a multi-objective gray wolf optimization technique. In Scenario A, the focused objectives are the total destructed exergy and the cost of producing liquefied hydrogen. Meanwhile, Scenario B integrates the sustainability index and the overall system cost rate as primary criteria. Scenario A exhibits more favorable operational conditions and outcomes than scenario B, showing the objectives mentioned as 9955 kW and 3.25 $/kg, respectively. In this scenario, the sustainability index, the overall investment cost rate, and the net present value are obtained to be 1.74, 236 $/h, and 205 M$, correspondingly.

Improving Supervisory Consultant Performance in Construction Projects: Assessments in the LKPP's SIKaP Application for Enhanced Efficiency

This article focuses on enhancing the performance of supervisory consultants in construction projects through assessments conducted in the LKPP's SIKaP application. Supervision plays a crucial role in ensuring the smooth execution of construction activities and addressing potential obstacles. The quality and safety of construction operations have become increasingly important, necessitating effective supervision. The article highlights the importance of conducting assessments to measure the success of supervisory consultants in meeting project objectives and adhering to established standards. It emphasizes the evaluation of various performance criteria, including human resources, equipment, materials, costs, time, and quality. The assessment process enables the identification of strengths and weaknesses, facilitating corrective measures and improving future performance. The article also emphasizes the interconnectedness of construction supervision and project management, with project management playing a pivotal role in achieving project goals. Communication management is highlighted as a crucial aspect for effective project execution. The regulatory framework governing technical supervision activities in construction projects is discussed, along with the roles and responsibilities of construction management and construction supervision service providers. The article emphasizes the importance of on-site inspections, project administration, progress monitoring, and quality management in construction supervision. Lastly, the article discusses the evaluation of providers' performance in goods/services procurement, emphasizing the importance of quality, cost efficiency, and adherence to standards. The implementation of the SIKaP application is seen as a means to enhance transparency, accountability, and project quality in the construction industry, fostering a culture of continuous improvement and industry benchmarking.

Evaluation of aircraft engine performance during takeoff phase with machine learning methods

During the takeoff phase, aircraft engines reach maximum speed and temperature to achieve the required thrust. Due to these harsh operating conditions, the performance of aircraft engines may decrease. This decrease in performance increases both fuel consumption and environmental damage. Reducing or eliminating the damages caused by aircraft is among the objectives of ICAO. In order to achieve this goal, aircraft engines are compulsorily tested, evaluated by experts and certified. The data obtained during the test process is recorded and stored in the engine emission databank (EEDB). During the takeoff phase, there is no system that can evaluate aircraft engines without dismantling and without expert knowledge. In this study, EEDB 2019 and 2021 takeoff phase data sets were used. Fuel flow T/O parameter is an important parameter used both in the calculation of aircraft emissions and in the evaluation of engine performance. Gaussian process regression (GPR), support vector machine (SVM) and multilayer perceptron (MLP) models were used to estimate the fuel flow T/O parameter. The results obtained were compared according to error performance criteria and the best model was selected. In MATLAB® environment, confidence intervals were plotted with the estimated fuel flow T/O value at 99% confidence level. This study demonstrates that the performance evaluation of aircraft engines during the takeoff phase can be performed without the need for expert knowledge.

Development and validation of a multiresidue method for the determination of antibiotic residues in crawfish using LCMS/MS

ABSTRACT This study developed a rapid multi-class method for determining 29 antibiotic residues in crawfish using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. A quick and affordable extraction method was employed, and sample preparation was performed using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) technique. The extraction process involved adding acetonitrile to crawfish samples. The sample was homogenised with a solution of sodium citrate buffer and sodium EDTA, followed by a cleanup step. The method was validated according to European Union (EU) guidelines 2002/657/EC. The limit of quantitation (LOQ) for all antibiotics was 5 µg/kg, except for flumequine and trimethoprim, which had LOQs of 2.5 µg/kg. The LOQ for the tetracycline group was 25 µg/kg, and for chloramphenicol, it was 0.015 µg/kg. The average recoveries at different concentration levels varied between 60–120%. The precision, expressed as repeatability and reproducibility, was calculated to be less than 16%. Thirty crawfish samples collected from local Egyptian market were monitored for antibiotic residues. The results revealed contamination with antibiotics belonging to three different groups. Of the thirty samples, 27% were contaminated with ciprofloxacin and enrofloxacin, 17% with chlortetracycline and oxytetracycline, 7% with oxolinic acid, and 3% with sulphamethazine. The applicability of the developed method was proven through successful proficiency testing. The developed method met performance criteria and is suitable for monitoring these antibiotics in crawfish.

Generalized and novel iterative scheme for best approximate solution of large and sparse augmented linear systems

This article presents a generalized novel iterative technique for obtaining the approximate solution of systems of linear equations(ABBT0)(xy)=(pq). Parameters involved in the scheme play a vital role to obtain the rapid and best approximate solution. The technique is applied to some important problems and the results are presented in detail. The article compares the effectiveness of the new presented iterative scheme with modified SOR-like method, generalized SOR and SOR-like method for solving large systems of linear equations. The convergence criteria for the iterative scheme are also analysed and it can be observed in the article that the theoretical derivation is supported by numerical calculations and graphical exhibition. Overall, the article provides a new and effective method with a detailed analysis of its performance and convergence criteria for solving systems of linear equations of the form presented. The newly derived technique has potential applications in various fields of science and engineering where systems of linear equations arise and need to be solved.

Five-Repetition Sit-to-Stand Test as Predictor of Mortality in High Risk COPD Patients

ObjectiveTo determine if adding performance on the five-repetition sit-to-stand test (5-STS) to chronic obstructive pulmonary disease (COPD) high-risk criteria, proposed by the Spanish COPD guidelines (GesEPOC), affects mortality prognosis. MethodsObservational study of COPD outpatients involved prospective follow-up for 5 years. Patients were classified based on 5-STS performance and risk criteria proposed by GesEPOC version 2021. Outcome measures were 5-year mortality timing and rate. Kaplan–Meier curves and univariate and multivariate Cox proportional-hazard analyses, analysis of variance, and univariate and multivariate linear and logistic regression models were used. ResultsOne hundred and thirty-seven patients were included. Mean age was 66±8.3 years, and 87.6% were men. Of them, 115 (83.9%) were classified as high risk, 43 (34.4%) of whom had poor performance on the 5-STS. Overall mortality at 5 years was 27% and was significantly higher in the high-risk (29.6%) compared with the low-risk (13.6%) group. Among high-risk patients, mortality at 5 years was significantly worse with poor 5-STS performance (60.5%) compared with non-poor performance (11.1%). Poor performance on the 5-STS was independently associated with increased 5-year mortality risk (HR 4.70; 95% CI: 1.96–11.27) in a model adjusted for history of heart disease and dyspnea. ConclusionAmong high-risk COPD patients, those with poor performance on the 5-STS have a significantly higher mortality at 5 years than those with non-poor 5-STS performance.

Determination of riding comfort on cycleways using a smartphone application

Well maintained cycleways will encourage more people to cycle, as the condition of cycleways is important for the safety, accessibility and riding comfort of cyclists. Despite that, only a few models used to describe the quality of service for cyclists take the surface condition into account. Objective measuring methods are needed to enable reliable and effective assessment of surface conditions, and measurable performance criteria related to the needs of cyclists should be developed. The purpose of this study has been to test the reliability and validity of using accelerometers in smartphones to assess the riding comfort on cycleways. A smartphone application converting three-dimensional accelerometer measurements into a single indicator for cycleways has been used to assess road surfaces in two field studies, in Sweden and Norway, respectively. Both studies assessed test sections of varying quality. To relate the measurements to subjective riding comfort assessments by cyclists, recruited cyclists collected quantitative data using the app, whilst also rating their perceived riding comfort by completing a survey. Measurements were also related to standard road surface condition indicators, generated from a road surface tester equipped with 19 laser sensors: international roughness index (IRI), mega- and macrotexture. The results show that it is possible to describe the unevenness of a cycleway using the technology present in smartphones. A software application can be used to collect and analyse data from the acceleration sensors in the phone, which can then be used to describe the riding comfort of cyclists. It is mainly the unevenness in the 50–1000 mm size-range that create the greatest discomfort for cyclists, and intermittent vibrations are perceived as more uncomfortable than more evenly distributed vibrations. Therefore, IRI is not a relevant measurement for describing the riding comfort of cyclists.

A Comprehensive Survey On Machine Learning-Based Intrusion Detection System for Vehicular Area Network Architectures

Today, the development of communication technologies causes changes in many different areas. One of these areas is VANET (Vehicular Area Network) application area. With the increase in usage areas in the VANET field, ensuring VANET network security has become more critical. Many different systems have been developed to detect attacks on VANET networks. Machine learning-based systems are one of the most widely used methods in developing these intrusion detection systems (IDS). In this article, research on machine learning-based VANET IDS, which has been done recently in the literature, has been carried out. First, VANET architecture and security requirements are presented, then a comprehensive literature summary is given, and comparisons are made on different parameters. As a result, it has been determined that many different machine learning models are used in IDSs and perform high-performance detection. In addition to the machine learning algorithm used in the performance of IDSs, it has been shown that many different parameters play a critical role in the performance. The paper aims to guide new studies in this field with the gains that will increase the performance of intrusion detection systems because of the literature comparison (considering criteria such as machine learning model, simulation tools, dataset, machine learning algorithm, and performance criteria).

Performance of Robust Type-2 Fuzzy Sliding Mode Control Compared to Various Conventional Controls of Doubly-Fed Induction Generator for Wind Power Conversion Systems

This paper presents a novel hybrid type-2 fuzzy sliding mode control approach for regulating active and reactive power exchanged with the utility grid by a doubly-fed induction generator in a wind energy conversion system. The main objective of this hybridization is to eliminate the steady-state chattering phenomenon inherent in sliding mode control while improving the transient delays caused by type-2 fuzzy controllers. In addition, the proposed control approach has proven to be successful in coping with varying generator parameters and exhibited good reference tracking. An in-depth comparative study with state-of-the-art advanced control techniques is also the focus of the present paper. The comparative study has three objectives, namely: a qualitative comparative study that aims to compare response times and reference tracking capabilities; a quantitative evaluation that takes into account time-integrated performance criteria; and finally, robustness capabilities. The simulation results, carried out in the Matlab/Simulink environment, have demonstrated the effectiveness and best performance of the proposed hybrid type-2 fuzzy sliding mode control with respect to other advanced techniques included in the comparison study.

Environmental assessment of hospital waste management practices: A study of hospitals in Kermanshah, Iran

This research aims to identify current procedures of hospital waste management in educational hospitals, in western Iran. This study examined upon to be current procedures of medical waste management focusing on the management of hazardous medical waste, under a circular economy. Three criteria environmental situation, environmental management, and environmental performance. The environmental assessment was done by pair matrixes between criteria and sub-criteria, and between scale levels of the indicators were done. The questionnaire structure adopted in the Romero and Carnero study. The Analytic Hierarchy Process method indicates that aspect of the hazardous waste improvement program is essential. The results demonstrated that 56 % of the total environmental criteria score was VERY DEFICIENT in the scale factors classification. The lowest values indicated in the environmental management aspect and 63 % of the total score was VERY DEFICIENT. The results indicated a deficient value in environmental criteria based on the values received for the commitment to environmental policy standards and waste management procedures. The results of environmental performance criteria have shown; that no data was on atmospheric emission. The lack of rules in green purchasing and renewable energy was indicated. In waste management criteria, the total value was reasonable, but there weren't comprehensive rules for redefining waste types and staff training obligations. However, the redefinition of rules, public and staff training, using new technologies, and determination of specific budgets and green teams by proper supervising cycle can be essential to improve hazardous waste management.

Occurrence and human risk assessment of pharmaceutically active compounds (PhACs) in indoor dust from homes, schools and offices

This study investigates the current situation and possible health risks due to pharmaceutically active compounds (PhACs) including analgesics, antibiotics, antifungals, anti-inflammatories, psychiatric and cardiovascular drugs, and metabolites, in indoor environments. To achieve this objective, a total of 85 dust samples were collected in 2022 from three different Spanish indoor environments: homes, classrooms, and offices. The analytical method was validated meeting SANTE/2020/12830 and SANTE/12682/2019 performance criteria. All indoor dust samples except one presented at least one PhAC. Although concentration levels ranged from < LOQ to 18 µg/g, only acetaminophen, thiabendazole, clotrimazole, and anhydroerythromycin showed quantification frequencies (Qf %) above 19% with median concentrations of 166 ng/g, 74 ng/g, 25 ng/g and 14 ng/g, respectively. The PhAC distribution between dust deposited on the floor and settled on elevated (> 0.5 m) surfaces was assessed but no significant differences (p > 0.05, Mann–Whitney U-test) were found. However, concentrations quantified at the three types of locations showed significant differences (p < 0.05, Kruskal–Wallis H-test). Homes turned out to be the indoor environment with higher pharmaceutical concentrations, especially acetaminophen (678 ng/g, median). The use of these medicines and their subsequent removal from the body were identified as the main PhAC sources in indoor dust. Relationships between occupant habits, building characteristics, and/or medicine consumption and PhAC concentrations were studied. Finally, on account of concentration differences, estimated daily intakes (EDIs) for inhalation, ingestion and dermal adsorption exposure pathways were calculated for toddlers, adolescents and adults in homes, classrooms and offices separately. Results proved that dust ingestion is the main route of exposure, contributing more than 99% in all indoor environments. Moreover, PhAC intakes for all studied groups, at occupational locations (classrooms and offices) are much lower than that obtained for homes, where hazard indexes (HIs) obtained for acetaminophen (7%—12%) and clotrimazole (4%-7%) at the worst scenario (P95) highlight the need for continuous monitoring.

Development of Ground Control Station for Unmanned Aerial Vehicles

Unmanned aerial vehicles (UAVs) have emerged as important tools in various industries, from military research to civilian applications such as agriculture, disaster management and research. This paper examines the technological development of GCS and current state-of-the-art developments, including advances in hardware, software, and human-machine interfaces. Through a systematic review of recent research, we identify key policy considerations, performance criteria, and challenges associated with GCS development. In addition, we explore autonomy, artificial intelligence integration, cybersecurity, interoperability standards, and other development trends that are changing the UAV industry landscape. Combining insights from academic literature, industry reports, and technology developments, this review provides a comprehensive understanding and new idea of the state of GCS technology and valuable perspectives on future research directions and practical applications in UAV systems.

TINJAUAN TEBAL PERKERASAN PADA RUAS JALAN MARISA-MOTOLOHU IV KABUPATEN POHUWATO

Review of Pavement Thickness on Marisa Motolohu IV Road Section, Pohuwato Regency Marisa – Motolohu IV Road is a collector road which is a very useful transportation in the community and a road to agropolitan access in Pohuwato Regency, Gorontalo Province. In improving the road, adequate studies are needed to achieve optimal benefits. Road pavement thickness planning uses the SNI/AASHTO 93 method. Traffic enumeration surveys are carried out on road sections located in the study area. Subgrade research to find representative CBR values. In this planning stage, the criteria considered in this planning are traffic volume, time limits, traffic loads, reliability, environmental conditions, road performance criteria, drainage factors. Field conditions (existing) on ​​the Marisa – Motolohu IV section are (D1) 5.0 cm, base layer (D2) 10.0 cm, subbase layer (D3) 15 cm. The results of the study obtained the thickness of each pavement, namely: surface layer (D1) 8.0 cm, upper foundation layer (D2) 13 cm, lower foundation layer (D3) 19 cm. This study can be used as a comparison in previous planning using different methods.

Application of Analytical Quality by Design to the development and validation of reduced and non-reduced capillary electrophoresis analytical procedures for mAb purity determination

Capillary electrophoresis-sodium dodecyl sulfate (CE-SDS) is a common analytical procedure used to quantitate critical quality attributes relating to the purity and glycosylation of monoclonal antibodies (mAbs). In this study, the application of an Analytical Quality by Design framework incorporating Design of Experiments was used to develop and validate both non-reduced (CE-NR) and reduced (CE-R) versions of this analytical procedure. Formal risk assessments were used to identify critical method attributes for optimization based on their potential impacts to performance criteria outlined in an analytical target profile. The resulting response surfaces connecting these critical factors to method performance were then utilized to generate a harmonized procedure to reduce execution risk across CE-R and CE-NR applications. Validation of these procedures according to regulatory guidelines support that they meet their required performance criteria, and a multivariate assessment of procedure robustness indicates that method parameters are in a sufficient state of control to ensure appropriate quantitation of mAb quality. Overall, this study demonstrates the utility of adopting an Analytical Quality by Design framework to leverage multidimensional knowledge from multiple critical method parameters to ensure an analytical procedure is fit-for-purpose.

Aerothermodynamic similarity criteria for turbines operating within non-periodic transition processes

The aerothermodynamic performance test is a prerequisite for investigating the turbine transition process. To enhance the safety and feasibility of the experiments while reducing energy costs, the target high-temperature transition processes must be converted to low-temperature ones based on the similarity criteria. However, the commonly used similarity criteria for turbine aerothermal performance are only applicable to steady states, rather than transition processes. This study presents a set of similarity criteria for turbines operating within non-periodic transition processes, according to the similarity of the dimensionless Navier-Stokes equations and time-variant definite conditions. Furthermore, the proposed similarity method ensures the similarity of the hysteresis effect by maintaining the uniformity of the dimensionless moments between the high- and low-temperature operating conditions. Comprehensive validations are carried out on two different turbines operating within transition processes, covering periodic processes with different pulsating frequencies and amplitudes, as well as non-periodic ones. Both the proposed and commonly used similarity methods are applied to obtain low-temperature performance curves, and the two curves are compared with the target high-temperature curve to evaluate the similarity accuracy of the corresponding methods. Regarding the deviations in the reduced power output between the high- and low-temperature operating conditions, the proposed similarity method exhibits similarity errors of no more than 2 %, which is only approximately 20 % of the errors produced by the commonly used method. Thus, the proposed similarity method has a high accuracy and is applicable to non-periodic transition processes.

Modeling and Implementation of PID Controller in Vehicle Ride Comfort Improvement Using Bond Graph

The proportional integral derivative (PID) controller method is a famous and influential approach used in a variety of engineering domain systems. This paper presents Bond Graph modelling and implementation of PID controller in the active quarter-vehicle suspension system for the purpose of achieving better ride comfort. Bond graph is a better tool for modelling multi-domain energy systems with control hardware associated with it. SYMBOL SHAKTI software is used to simulate the active vehicle suspension system, which is theoretically represented as a 4-DOF human Bio-dynamic model combined with a 3-DOF quarter automobile system. The suggested PID Controller's performance is contrasted with that of the passive model. To measure the effectiveness of the suggested PID controller suspension system, time domain evaluations of systems performance criteria are conducted. The findings show that a significant improvement in ride comfort is offered by the suggested Bond graph PID controller model of the active vehicle suspension.

Testing seismic isolators for the effect of maximum earthquake based on measure of cumulative energy

AbstractThis paper presents results on what the conditions of testing for assessing the adequacy of seismic isolators in the maximum considered earthquake should be by utilizing an approach in which the cumulative dissipated energy history is used as the performance parameter. This test is what is described as Item 4 in section 17.8.2.2 of standard ASCE/SEI 7. The approach used follows the paradigm of another study in which the history of temperature at the sliding interfaces or in the bulk of the lead core of isolators was used. In conducting this work, many isolation systems (a total of 96 systems, single friction pendulum, triple friction pendulum, and lead‐rubber) were used, with isolator models capable of simulating the effects of heating on the strength of the isolators. The study utilized a large set of bi‐directional ground motions with short‐ and long‐duration characteristics (71 pairs of short‐ and long‐duration ground motions, 96 isolation systems, three seismic intensities, for a total of 40,896 ground motion pairs). The adequacy tests were designed to reproduce various percentile cumulative energy histories obtained in the response history analysis. The requirements of these tests are compared to the testing requirements obtained by the use of temperature history as the performance criterion, and the test currently prescribed as test item 4 of section 17.8.2.2 of standard ASCE/SEI‐7. The study shows that use of the cumulative dissipated energy as the performance criterion for designing tests to represent the effects of maximum earthquake results in onerous testing requirements. This is because the cumulative energy increases monotonically without accounting for fluctuations in the seismic ground motion intensity, unlike the history of temperature at the sliding interfaces or the lead core of isolators. Accordingly, tests designed using the temperature as the performance criterion are recommended for use in specifications for testing.

Topology optimization of periodic cellular materials employing the finite-volume theory

Topology optimization is a technique used in engineering to determine the optimal distribution of material within a defined design domain. This technique has been applied to the design of cellular materials to create an efficient microstructural arrangement that meets the necessary performance criteria and minimizes the weight of the material. This article presents an innovative approach that combines topology optimization, a homogenization method based on the unit cell concept and finite-volume theory to design highly efficient periodic cellular materials with optimized macroscopic elastic properties. To determine the optimal microstructural topology, specific linear combinations of components of the homogenized elastic matrix are considered to obtain optimized elastic properties, such as maximum shear/bulk moduli, considering a prescribed volume fraction constraint of solid material. Numerical examples are analysed, and the results demonstrate the exceptional performance of this approach in achieving optimal designs of cellular materials characterized by chequerboard-free patterns without filtering techniques.