Computer modeling of a ventilated Trombe Wall—With actual performance results

Solar Energy ◽  
1980 ◽  
Vol 25 (3) ◽  
pp. 207-213 ◽  
Author(s):  
F.V. Robbins ◽  
C.K. Spillman
Keyword(s):  
Computer Modeling ◽  
Actual Performance ◽  
Trombe Wall ◽  
Performance Results

Modelling, analysis and experimental verification of air disc brake used in heavy duty vehicles

2021 ◽  
pp. 095440622110520
Author(s):  
İbrahim Can Güleryüz ◽  
Barış Yılmaz
Keyword(s):  
Design Stage ◽  
Maximum Deviation ◽  
Disc Brake ◽  
Commercial Vehicles ◽  
Actual Performance ◽  
Test Fixture ◽  
Simulink Model ◽  
Proposed Model ◽  
Mathematical Equations ◽  
Performance Results

This paper proposes a reliable mathematical model that can be used for design stage of new air disc brake (ADB) development projects. All three phases of braking mechanism (brake apply, brake release and automatic adjustment) are modelled by Matlab Simulink in consideration of hysteresis and adjuster performance experiments. Firstly, mathematical relations of each friction interfaces of air disc brake components are derived and mathematical equations adapted to the Simulink model. To ensure the accuracy of ADB system model, hysteresis and adjuster performance experiments are conducted on a prototype disc brake mechanism supported by a test fixture. This prototype single piston disc brake mechanism is fitted to wheel size in 17.5″ used in heavy commercial vehicles. The predicted clamping force, mechanical ratio, brake efficiency and adjuster rate results are verified by using experimental data. The maximum deviation in hysteresis results is 3.08%. Besides, the maximum deviation in adjuster performance results is 7.15%. The numerically and experimentally obtained hysteresis and adjuster performance results show good agreement. The proposed model is modified in consideration of mechanism supported by a brake calliper for predicting actual performance of single piston brake mechanism on the brake level. The hysteresis and the adjuster performance analyses are conducted by using modified ADB model to calculate the hysteresis based brake efficiency and the adjuster rate. The brake efficiency of new single piston brake design provides similar efficiency as the twin piston disc brake used in heavy commercial vehicles.

scholarly journals Flawed self-assessment: Investigating self- and other-perception of second language speech

2014 ◽  
Vol 19 (1) ◽  
pp. 122-140 ◽  
Author(s):  
PAVEL TROFIMOVICH ◽  
TALIA ISAACS ◽  
SARA KENNEDY ◽  
KAZUYA SAITO ◽  
DUSTIN CROWTHER
Keyword(s):  
Second Language ◽  
Cognitive Skills ◽  
Self Assessment ◽  
Actual Performance ◽  
Self And Other ◽  
Grammatical Accuracy ◽  
L2 Perception ◽  
Performance Results ◽  
The Relationship ◽  
Measures Of Performance

This study targeted the relationship between self- and other-assessment of accentedness and comprehensibility in second language (L2) speech, extending prior social and cognitive research documenting weak or non-existing links between people's self-assessment and objective measures of performance. Results of two experiments (N = 134) revealed mostly inaccurate self-assessment: speakers at the low end of the accentedness and comprehensibility scales overestimated their performance; speakers at the high end of each scale underestimated it. For both accent and comprehensibility, discrepancies in self- versus other-assessment were associated with listener-rated measures of phonological accuracy and temporal fluency but not with listener-rated measures of lexical appropriateness and richness, grammatical accuracy and complexity, or discourse structure. Findings suggest that inaccurate self-assessment is linked to the inherent complexity of L2 perception and production as cognitive skills and point to several ways of helping L2 speakers align or calibrate their self-assessment with their actual performance.

scholarly journals Comparison of Concept Transferring Procedures of Basic Idea between Handmade Design and Computer Modeling

2018 ◽  
Vol 3 (12) ◽  
pp. 43
Author(s):  
Pracha Pijukkana ◽  
Yanin Rugwongwan
Keyword(s):  
Academic Achievement ◽  
Open Access ◽  
Product Design ◽  
Computer Modeling ◽  
Publishing House ◽  
Industrial Product ◽  
Modeling Process ◽  
International Publishing ◽  
Performance Results ◽  
Open Access Article

This research aims to make a comparative study of the performance results between creating the basic idea designs by handmade design process and by computer modeling process. The study of product design by using handmade process and computer modeling process has the same objectives which are to generate ideas and encourage creativity in product design. Though these two processes are done by using different tools, they have the same idea of using the interactive between brain, hand, and forms that appear on the paper or on the computer to improve and Idea Development, Sketch Design. Also, these two processes are used as an approach to teach and learn industrial product design, they can be chosen to suit students with different features and can be used to increase academic achievement performance.Keywords: Basic Idea; Handmade Design; Computer Modeling; Industrial Product Design.eISSN 2398-4279 © 2018. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. https://doi.org/10.21834/ajqol.v3i11.116

Benchmarking for Competitive Advantage

1996 ◽  
Author(s):  
David Korpach ◽  
Mark Hutchison
Keyword(s):  
Cost Effective ◽  
Business Practices ◽  
Actual Performance ◽  
The Past ◽  
Cost Structures ◽  
Doing Business ◽  
Industry Standards ◽  
Cost Reductions ◽  
Reducing Costs ◽  
Performance Results

Both liquids pipeline and natural gas transportation companies have been confronted with increasing competition over the past several years. Shippers have become far more demanding, insisting that transporters provide more cost effective rates. As a result, pipeline companies are under increased pressure to reduce transportation rates. This scenario is also true for regulated pipelines where shippers are joining forces to pressure transporters to be more creative in their ways of doing business so they can provide lower tolls. In order to assess their current cost structures and identify the most appropriate areas of their business to focus improvement efforts, pipeline companies have benchmarked their performance against competitors and leaders in the industry. Companies have used the results from these benchmarking studies for several purposes: a) understand cost / activity driver relationships; b) obtain empirical versus anecdotal information; c) assess their current level of performance; d) identify opportunities for improvement, focusing efforts on areas with the greatest potential for cost reductions; e) establishing realistic performance improvement targets; f) challenge corporate “myths and legends”; and g) provide insights into leading business practices that have been used by other companies to improve efficiencies. Results from the benchmarking studies suggest that the pipeline industry is, in general, reacting to this pressure for lower transportation costs. Over the past three years, based on a sample of North American pipeline companies, both liquids and gas pipelines have reported improvements in operating costs on a unitized/normalized basis. These cost reductions have resulted from focusing improvement efforts on key areas of the business where performance was not up to industry standards. Modifying business practices in these areas has been critical in assisting these organizations in reducing costs. This paper will present a comprehensive approach to conducting pipeline benchmarking studies. Actual performance results for both gas transportation and liquids carriers will be discussed. The results will focus both on current cost levels as well as industry trends. In addition, it will provide insights into initiatives that have been successful in helping reduce cost structures, moving them towards being the “shipper of choice”.

scholarly journals A Calibration of the Solar Load Ratio Method to Determine the Heat Gain in PV-Trombe Walls

Energies ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 328
Author(s):  
Roberto Bruno ◽  
Piero Bevilacqua ◽  
Daniela Cirone ◽  
Stefania Perrella ◽  
Antonino Rollo
Keyword(s):  
Dimensionless Parameter ◽  
Load Ratio ◽  
Empirical Method ◽  
Ratio Method ◽  
Passive System ◽  
Actual Performance ◽  
Simulation Tools ◽  
Trombe Wall ◽  
Visual Impact ◽  
Energy Gains

The Trombe wall is a passive system used in buildings that indirectly transfers thermal energy to the adjacent environment by radiation and convection, and directly by the thermo-circulation that arises in the air cavity delimited between a transparent and an absorbing surface. Nevertheless, the latter is painted black to increase the energy gains, but this produces a negative visual impact and promotes the overheating risk in summer. To mitigate these aspects, a hybrid Trombe wall equipped with PV panels can be employed. The PV installation results in a more pleasing wall appearance and the overheating risk reduces because part of the absorbed solar radiation is transformed into electricity. To determine the actual performance of a such system, transient simulation tools are required to consider properly the wall thermal storage features, variation of the optical properties, air thermo-circulation, and PV power production. Alternatively, regarding the traditional Trombe wall, the literature provides a simplified empirical method based on the dimensionless parameter solar load ratio (SLR) that allows for preliminary evaluations and design. In this paper, the SLR method was calibrated to determine the monthly auxiliary energy to be supplied in buildings equipped with PV-Trombe walls in heating applications. The SLR method was tuned by a multiple linear regression by data provided by TRNSYS simulation that allowed to obtain the energy performances in actual conditions of PV-Trombe walls installed on the same building but located in different localities. The comparison between the TRNSYS results and the calibrated SLR method determined average errors ranging between 0.7% and 1.4%, demonstrating the validity of the proposed methodology.

Pessimistic Bias in Predictions of Performance Results

1995 ◽  
Vol 77 (3_suppl) ◽  
pp. 1363-1366
Author(s):  
Vadim Subbotin
Keyword(s):  
University Students ◽  
The Other ◽  
Practice Trial ◽  
Actual Performance ◽  
Functional Perspective ◽  
Performance Predictions ◽  
Performance Results

Realism in the performance predictions of 60 university students was investigated. After a practice trial on a task of creativity, one group of subjects were asked to state their expectations and the other group their hopes for their performance scores on the first and second test trials before each one. Both groups were unrealistically pessimistic about their performance: the first and second trial predictions of the expectation group as well as of the hope group were lower than their actual performance scores. In all cases (except the second-trial prediction of the hope group) the differences reached significance. Results are explained from the functional perspective. It is suggested that unrealistically low predictions may serve an affective function (feeling better).

Predictive Workload Models and Multiple-Task Performance

1992 ◽  
Vol 36 (1) ◽  
pp. 12-16 ◽  
Author(s):  
Kenneth J. Sarno ◽  
Christopher D. Wickens
Keyword(s):  
Task Performance ◽  
Cognitive Processing ◽  
Task Demands ◽  
Actual Performance ◽  
Predicting Performance ◽  
Model Predictions ◽  
Exclusive Or ◽  
Performance Results ◽  
Workload Models ◽  
Multiple Task

The goal of the present study was to evaluate three workload models, VACP (Aldrich, Szabo, and Bierbaum, 1988), TLAP (Parks and Boucek, 1988), and WINDEX (North & Riley, 1988), in terms of how well they account for task performance results gathered from a laboratory experiment. The models are discussed in terms of their treatment of five timesharing issues: 1) the nature of workload components (mutually exclusive or partially overlapping); 2) the utility of distinguishing between cognitive processing codes; 3) classifying voice response (psychomotor function or separate component; 4) qualitative vs. quantitative coding of task demands; and 5) the utility of an overload red-line. A correlational analysis was performed on model predictions versus actual performance for 16 different task loading conditions, to evaluate each of the three workload models. All three models did a good job of predicting performance differences across conditions, accounting for between 61% and 77% of the variance, with the TLAP model providing the best prediction. In addition, a hybrid model was developed (using the “optimal” assumptions concerning the five timesharing issues) which accounted for 85% of the variance. The results are discussed in terms of the viability of the assumptions made by each of the models with respect to the five timesharing issues.

scholarly journals Low-power ultra-small Edge AI Accelerators for Image Recognition with Convolution Neural Networks: Analysis and Future Directions

2021 ◽  
Author(s):  
Weison Lin ◽  
Adewale Adetomi ◽  
Tughrul Arslan
Keyword(s):  
Low Power ◽  
Image Recognition ◽  
Performance Metrics ◽  
Actual Performance ◽  
Performance Targets ◽  
Future Design ◽  
Prior Art ◽  
Actual Evaluation ◽  
Performance Results ◽  
Hostile Environments

Edge AI accelerators have been emerging as a solution for near customers’ applications in areas such as unmanned aerial vehicles (UAVs), image recognition sensors, wearable devices, robotics, and remote sensing satellites. These applications not only require meeting performance targets but also meeting strict reliability and resilience constraints due to operations in harsh and hostile environments. Numerous research articles have been proposed, but not all of these include full specifications. Most of these tend to compare their architecture with other existing CPUs, GPUs, or other reference research. This implies that the performance results of the articles are not comprehensive. Thus, this work lists the three key features in the specifications such as computation ability, power consumption, and the area size of prior art edge AI accelerators and the CGRA accelerators during the past few years to define and evaluate the low power ultra-small edge AI accelerators. We introduce the actual evaluation results showing the trend in edge AI accelerator design about key performance metrics to guide designers on the actual performance of existing edge AI accelerators’ capability and provide future design directions and trends for other applications with challenging constraints.

scholarly journals Comparison of Concept Transferring Procedures of Basic Idea between Handmade Design and Computer Modeling

2017 ◽  
Vol 2 (5) ◽  
pp. 121
Author(s):  
Pracha Pijukkana ◽  
Yanin Rugwongwan
Keyword(s):  
Academic Achievement ◽  
Open Access ◽  
Product Design ◽  
Computer Modeling ◽  
Publishing House ◽  
Industrial Product ◽  
Modeling Process ◽  
International Publishing ◽  
Performance Results ◽  
Open Access Article

This research aims to make a comparative study of the performance results between creating the basic idea designs by handmade design process and by computer modeling process. The study of product design by using handmade process and computer modeling process has the same objectives which are to generate ideas and encourage creativity in product design. Though these two processes are done by using different tools, they have the same idea of using the interactive between brain, hand, and forms that appear on the paper or on the computer to improve and Idea Development, Sketch Design. Also, these two processes are used as an approach to teach and learn industrial product design, they can be chosen to suit students with different features and can be used to increase academic achievement performance.Keywords: Basic Idea, Handmade Design, Computer Modeling, Industrial Product Design.ISSN: 2398-4287© 2017. The Authors. Published for AMER ABRA by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, UniversitiTeknologi MARA, Malaysia.

Monitoring Microturbine Generators Installed in the South Coast Air Basin

2005 ◽  
Author(s):  
Marc Medrano ◽  
Richard L. Hack ◽  
Steve Lee ◽  
Vincent G. McDonell ◽  
Scott Samuelsen ◽  
...  
Keyword(s):  
Distributed Generation ◽  
South Coast ◽  
Total Output ◽  
Air Quality Management ◽  
The South ◽  
Actual Performance ◽  
Operational Characteristics ◽  
Natural Gas Prices ◽  
South Coast Air Basin ◽  
Performance Results

Microturbine generators offer an interesting early commercial strategy for implementation of distributed generation. Through a program sponsored by the South Coast Air Quality Management District (SCAQMD), 207 microturbines of 30 and 60kW output are deployed or in the process of being deployed at 47 sites throughout the SCAQMD. These units are being monitored for general operational characteristics such as hours operated, number of starts, total output. In addition, several of the sites have been outfitted with additional sensors that facilitate the collection of efficiency information. Performance results from two of these sites are presented along with corresponding economic evaluation. The results indicate that actual performance does not reach the manufacturer’s specifications and that the recent increases in natural gas prices have increased the projected payback period for the equipment.

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