scholarly journals System efficiency prediction of a 1kW capacity grid-tied photovoltaic inverter

2021 ◽  
Vol 12 (2) ◽  
pp. 1177
Author(s):  
Saurav Das ◽  
Dhiman Chowdhury ◽  
Md. Abdur Razzak
Keyword(s):  
Meteorological Data ◽  
Performance Assessments ◽  
Performance Ratio ◽  
Medium Voltage ◽  
System Parameters ◽  
Optimum Energy ◽  
Solar Plant ◽  
And Performance ◽  
The Impact ◽  
Angle Calculation

<p>This article presents the system design and prediction performance of a 1kW capacity grid-tied photovoltaic inverter applicable for low or medium-voltage electrical distri-bution networks. System parameters, for instance, the longitude and latitude of the solar plant location, panel orientation, tilt and azimuth angle calculation, feasibility testing, optimal sizing of installment are analyzed in the model and the utility is sim-ulated precisely to construct an efficient solar power plant for residential applications. In this paper, meteorological data are computed to discuss the impact of environmen-tal variables. As regards ensuring reliability and sustenance, a simulation model of the system of interest is tested in the PVsyst software package. Simulation results yield that the optimum energy injected to the national grid from the solar plant, specific pro-duction, and performance ratio are 1676kWh/year, 1552kWh/kWp/year, and 79.29% respectively. Moreover, the predicted carbon footprint reduction is 23.467 tons during the 30 years lifetime of the system. Therefore, the performance assessments affirm the effectiveness of the proposed research.</p>

scholarly journals Age and Gender Differences in Performance at Cross Triathlon World Championships

2018 ◽  
Vol 25 (3) ◽  
pp. 17-22 ◽  
Author(s):  
Oscar Romero-Ramos ◽  
Emilio Fernández-Rodríguez ◽  
Rafael Merino-Marbán ◽  
Daniel Mayorga-Vega ◽  
Robert Podstawski
Keyword(s):  
Age Groups ◽  
Performance Ratio ◽  
Age Group ◽  
Men And Women ◽  
Race Time ◽  
Age Related ◽  
And Performance ◽  
And Gender ◽  
High Level ◽  
The Impact

Abstract Introduction. Cross triathlon is a sport consisting of three segments: swimming, off-road cycling, and running. Our study analyses the differences in performance between genders and changes in performance in selected age categories at the ITU Cross World Championships held between 2011 and 2016. Material and methods. During this period, a total of 1,933 triathletes were analysed (1,472 men and 461 women). Two-way analyses of variance (ANOVA) were used to examine the impact of sex differences and age-related changes on performance (time, percentage of time, and performance ratio) in swimming, cycling, running, and total race. Results. The age groups with the highest level of participation were persons aged 40-44 and 45-49 years among men and women, respectively. With regards to performance in the different age groups, in men and women, its high level was maintained between 25 and 49 years, and it decreased significantly from the age of 50-54. In men, the best results in cycling and total race time were obtained in the 30-34 age group and in swimming and running in the 40-44 group. Women obtained the best results in running in the 25-29 age group, in cycling in the 30-34 group, and in swimming and total race time in the 35-39 group. Conclusions. The results of the study have confirmed that there is a demand for sports in 40+ age groups. As for performance in the different age groups, it was on a high level between 25 and 49 years and decreased significantly from the age of 50-54 onwards. According to these results, the sports training of these triathletes should be oriented so that they obtain their best results between 30 and 35 years of age.

Analyzing the Robustness of Two-Scale Command Shaping for Reducing Powertrain Vibration During Engine Restart

2016 ◽  
Author(s):  
J. Justin Wilbanks ◽  
Michael J. Leamy
Keyword(s):  
Hybrid Electric Vehicle ◽  
Initial Conditions ◽  
Combustion Engine ◽  
Perturbation Technique ◽  
Successful Implementation ◽  
Time Varying ◽  
Command Shaping ◽  
System Parameters ◽  
And Performance ◽  
The Impact

This paper analyzes the robustness of a two-scale command shaping strategy for reducing vibrations in hybrid electric vehicle (HEV) powertrains during engine restart. Propagation of HEVs through the automobile market depends on their perceived quality and performance. In this work, a two-scale command shaping strategy addresses the drivability of the vehicle by focusing on the reduction of noise, vibration, and harshness (NVH) issues associated with restarting the internal combustion engine (ICE) during a mode transition. The strategy tailors the electric machine (EM) torque profile, which consists of a linear and time-varying component, to significantly mitigate the powertrain and chassis vibrations for a smoother ICE startup. The time-varying EM torque component is calculated by applying a perturbation technique for separating the scales of an analytical ICE model, which isolates the ICE nonlinear response. Command shaping is then applied to the linear problem governed by the remaining scale. Simulations confirm that the two-scale command shaping strategy is a straightforward technique for reducing powertrain and chassis vibrations during ICE restart. In real-time implementation, inaccuracies or variations in system parameters and initial conditions arising from the operating condition or from general wear during a vehicle’s life cycle will occur. Therefore, successful implementation of the two-scale command shaping strategy relies upon the robustness of the perturbation technique and command shaping to these variations. This paper validates the perturbation technique’s robustness to variations in the ICE parameters and initial conditions. Robust command shaping methods are also explored to decrease the impact of system parameter variations on the efficacy of command shaping. Improving the overall robustness of the two-scale command shaping strategy will increase the applicability to consumer HEVs by ensuring its performance under variations in system parameters.

Impact of Risk Attitude on Risk, Opportunity, and Performance Assessment of Construction Projects

2021 ◽  
pp. 875697282098567
Author(s):  
Abroon Qazi ◽  
Abdelkader Daghfous ◽  
M. Sajid Khan
Keyword(s):  
Construction Industry ◽  
Construction Projects ◽  
Risk Attitude ◽  
Project Performance ◽  
Performance Assessments ◽  
Multiple Dimensions ◽  
Expected Performance ◽  
Project Uncertainty ◽  
And Performance ◽  
The Impact

This article explores the impact of risk attitude on the assessment of project uncertainty encompassing both risk and opportunity and expected project performance. A survey was conducted involving project risk management experts from the construction industry, and the data collected were analyzed using various statistical techniques. The findings reveal that the impact of risk attitude significantly varies across multiple dimensions of project uncertainty and project performance. To the best of the authors’ knowledge, the association between risk attitude and project uncertainty and expected performance assessments has never been explored while capturing multiple dimensions of project uncertainty and performance.

scholarly journals Novel availability and performance ratio for internal transportation and manufacturing processes in job shop company

2020 ◽  
Vol 13 (1) ◽  
pp. 1
Author(s):  
Perumal Puvanasvaran ◽  
Yong Siang Teoh ◽  
Teruaki Ito
Keyword(s):  
Production System ◽  
Lead Time ◽  
Performance Ratio ◽  
Manufacturing Processes ◽  
Customer Demand ◽  
Demand Fulfillment ◽  
Transportation Process ◽  
And Performance ◽  
Equipment Utilization ◽  
The Impact

Purpose: Purpose of this study includes the quantification of the impact of transportation efficiency onto the workstations the transportation serves in term of throughput and total lead time elapsed by product. Besides, it aims to synchronize the capacity available among workstations throughout a production line by studying the upper limit of throughput could be afforded by each workstation as well as their connection with each other. This study is also done on the purpose of promoting fulfillment of customer demand at shorter delivery time and minimal equipment utilization. Investigation on implementation of Overall Equipment Effectiveness (OEE) in an aerospace part-manufacturing company is studied to track out the potential opportunities to be improved.Design/methodology/approach: Site observation is conducted on all the five manufacturing workstations in the aforementioned aerospace part manufacturing company. Time data of both automated processes and manual processes are collected and they are used to construct simulation model. From that, various scenarios of transportation efficiency are simulated in Experiment 1. In addition, Experiment 2 is also set to examine the maximum capacity of each workstation. All of these are to highlight the relationship between workstation and processes and to verify the condition of imbalanced capacity among workstations in the company. In short, this has necessitated the integration of workstation and transportation activities within the company. These are followed by proposal of measures to quantify the wastes identified.Findings: The paper finds that implementation of OEE alone does not consider the reasonability of customer demand fulfillment. The results show that both transportation efficiency and imbalanced capacity throughout production system are not emphasized by OEE implementation in the case company. Therefore, responsibility of all workstations and transportation process in delivering demand on time are quantified. Transportation process which serves as the connectors of manufacturing processes is quantified and monitored by proposed Transportation Measure (TM) whereas workstations are measured using novel availability and performance ratio.Research limitations/implications: Future research should be conducted to examine the impact of other station within a company such as warehouse and logistic department to the performance of equipment and materials in manufacturing workstation. Besides, the material availability as well as the skills or performance of man power could be further incorporated into the measures to consider all the entities involved in manufacturing processes.Practical implications: The proposed availability and performance ratio for both transportation and manufacturing processes, which are related to each other, help in promoting better effectiveness of production system in terms of production amount and lead time. Besides, reasonable utilization equipment and minimal consumption of material are incorporated in the measures to promote Lean way in fulfilling customer demand. The effectiveness of entire production line is examined as a unity with joint responsibility under varying transportation efficiency and cycle time of each workstation. Both measures could be implemented together to optimize the production system and quantify the hidden wastes which are neglected in the OEE implementation.Originality/value: The novel availability and performance ratio are proposed to consider customer demand, historical equipment utilization and Takt time of each workstation to examine the possibility and reasonability of demand fulfillment. This prevents both over-processing and overproduction issues which are invisible in OEE. Furthermore, delay propagation throughout production system and interrelationship between processes are quantified under transportation measure. Other novelty of the paper is that it monitors the waiting time and lead time spent in each workstation at the same time considering utilization of workstation. The proposed Transportation Measure (TM) aims to reduce the queue length and waiting time at destination workstation at minimal utilization of forklift. It also promotes less capacity investment in transportation and prioritizes its scheduling according to urgency of destination workstation.

scholarly journals Buried Treasure: Contradictions in the Perception and Reality of Women's Leadership

2021 ◽  
Vol 12 ◽  
Author(s):  
Margaret M. Hopkins ◽  
Deborah Anne O'Neil ◽  
Diana Bilimoria ◽  
Alison Broadfoot
Keyword(s):  
Financial Services ◽  
Leadership Behaviors ◽  
Negative Relationship ◽  
Women's Leadership ◽  
Performance Assessments ◽  
Senior Leaders ◽  
Leadership Performance ◽  
Leadership Potential ◽  
And Performance ◽  
The Impact

The impact of gender on assessments of leadership performance and leadership potential was examined through two clusters of leadership behaviors, one set related to traditional constructions of leadership labeled directing others and another associated with contemporary constructions of leadership labeled engaging others. Based on data collected from a sample of 91 senior leaders in one US financial services organization over a 3-year period prior to Covid-19, the results showed a negative relationship between directing others behaviors and leadership potential ratings for females and a positive relationship between these variables for males. A negative relationship between engaging others behaviors and performance assessments was also found for females. This study highlights the continuing bias in leadership assessments of women and explores the contradictions between the perception and the reality of women's leadership.

The Impact of Property Characteristics on Economic Performance of Russian Industrial Enterprises

2005 ◽  
pp. 53-68 ◽  
Author(s):  
R. Kapeliushnikov ◽  
N. Demina
Keyword(s):  
Detailed Analysis ◽  
Economic Performance ◽  
Ownership Concentration ◽  
Corporate Sector ◽  
Concentrated Ownership ◽  
Industrial Enterprises ◽  
Russian Industry ◽  
Control Premium ◽  
And Performance ◽  
The Impact

The paper provides new survey evidence on effects of concentrated ownership upon investment and performance in Russian industrial enterprises. Authors trace major changes in their ownership profile, assess pace of post-privatization redistribution of shareholdings and provide evidence on ownership concentration in the Russian industry. The major econometric findings are that the first largest shareholding is negatively associated with the firm’s investment and performance but surprisingly the second largest shareholding is positively associated with them. Moreover, these relationships do not depend on identity of majority shareholders. These results are consistent with the assumption that the entrenched controlling owners are engaged in extracting "control premium" but sizable shareholdings accumulated by other blockholders may put brakes on their expropriating behavior and thus be conductive for efficiency enhancing. The most interesting topic for further more detailed analysis is formation, stability and roles of coalitions of large blockholders in the corporate sector of post-socialist countries.

The Impact of Women’s Employment on Marital Stability in Qatar Society

2019 ◽  
Vol 10 (2) ◽  
pp. 144-151
Author(s):  
Noora Ahmed Lari ◽  
Keyword(s):  
Work Motivation ◽  
Marital Stability ◽  
Female Employment ◽  
Social Constraints ◽  
Primary Data ◽  
Family Policies ◽  
Insufficient Time ◽  
And Performance ◽  
The Impact ◽  
The Relationship

The State of Qatar has implemented several family policies in order to improve the wellbeing of Qatari families and ensure fair distribution of development benefits for both men and women. However, there is a linkage between female employment outside the home and instability in the marriages of Qatari families. This paper investigates the impact of female employment on marital stability, based on the results of primary data collected in Qatar, a questionnaire that consisted of several sections such as challenges in the workplace, supervisor, family and spouse relations, work motivation and performance. Of the 824 questionnaires that were returned, 807 were completed and valid for analysis. Regression analysis and an ANOVA test have been used to test the relationship between the variables. The results of the research have produced mixed findings about how wives’ employment increases marital instability and have yielded few significant differences on mean scores of discuss on work demands, insufficient time together, housework, financial matters, communication, relatives and rearing children. The results indicates that in general Qatar working women face several challenges in relation to their marital life as part of cultural and social constraints.

The Role of Research and Innovation in the Transformation of Agri-Food Systems

2018 ◽  
Vol 12 (2) ◽  
pp. 60-63
Author(s):  
Mariana Sandu ◽  
Stefan Mantea
Keyword(s):  
Technological Progress ◽  
Food Systems ◽  
Food System ◽  
Agricultural Research ◽  
Research And Innovation ◽  
And Performance ◽  
The Impact ◽  
Determinant Factor ◽  
Rapid Transformation

Abstract Agri-food systems include branching ramifications, which connect in the upstream the input suppliers with farmers, and downstream farmers, processors, retailers and consumers. In the last decades, at the level of the regions, food systems have undergone rapid transformation as a result of technological progress. The paper analyzes the changes made to the structure, behavior and performance of the agri-food system and the impact on farmers and consumers. Also, the role of agricultural research as a determinant factor of transformation of agri-food system is analyzed. The research objective is to develop technologies that cover the entire food chain (from farm to fork) and meet the specific requirements of consumers (from fork to farm) through scientific solutions in line with the principles of sustainable agriculture and ensuring the safety and food safety of the population.

Analyzing the impact of financial momentum on the development of the economy

2020 ◽  
Vol 26 (2) ◽  
pp. 299-315
Author(s):  
V.V. Smirnov
Keyword(s):  
Financial Regulation ◽  
Systems Approach ◽  
Financial System ◽  
Modern Economic ◽  
And Performance ◽  
The Interest Rate ◽  
National Economies ◽  
Economic Ties ◽  
The Impact ◽  
Global Financial System

Subject. The article discusses the momentum in finance. Objectives. The study reveals the impact of financial momentum as the unity of antipodes in the development of the national economy. Methods. The study is based on a systems approach and methods of descriptive statistics. Results. I discover the ultimate goal of globalization, i.e. the substantive simplification of national economies and strengthening of global economic ties. The goals determine the logic tendency of national economies for reducing the interest rate so as to gain the financial momentum and, consequently, fanning the crisis risk in the global financial system. The global financial system became the substance of global economic processes, which determined development opportunities of national economies. I reveal what countries have the high and low financial momentum. Conclusions and Relevance. Being the unity of antipodes in the modern economic development, financial momentum causes countries to lose their economic identity, making them just functions of the global financial system. The cyclical development model of national economies is replaced with the metron model that rests on fluctuating advanced economies with the low financial momentum at its bottom and emerging economies at its top. The findings crystallize the concept and new competencies for a person who decide on the determination and performance of financial regulation activities.

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