• Journal of Power Electronics
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• 제3권4호
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• pp.230-238
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• 2003

Electric vehicles (EV) demands for greater acceleration, performance and vehicle range in pure electric vehicles plus mandated requirements to further reduce emissions in hybrid electric vehicles (HEV) increase the appeal for combined on-board energy storage systems and generators. And the power electronics plays an important role in providing an interface between fuel cells (FC) and loads. This paper deals with a multiple input DC-DC power converter devoted to combine the power flowing of multi-source on energy systems. The multi-source is composed of (i) FC system as a prime power demands, (ii) super capacitor banks as energy storage devices for high and intense power demands, (iii) superconducting magnetic energy storage system (SMES), (iv) multiple input DC-DC power converter and (v) a three phase inverter-fed permanent magnet synchronous motor as a drive. In this system, It is used super capacitor banks and superconducting magnetic energy replaces from the battery system. The modeling and transient performance simulation is effective for reducing transient influence caused by sudden charge of effective load. The main purpose of power electronic converters is to convert the DC power output from the fuel cell and other to a suitable AC voltage, which can be connected to electric loads directly (PMSM). The fuel cell and other output is connected to the DC-DC converter, which regulates the DC link voltage.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권10호
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• pp.4072-4091
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• 2015

A separation of text and non-text elements plays an important role in document layout analysis. A number of approaches have been proposed but the quality of separation result is still limited due to the complex of the document layout. In this paper, we present an efficient method for the classification of text and non-text components in document image. It is the combination of whitespace analysis with multi-layer homogeneous regions which called recursive filter. Firstly, the input binary document is analyzed by connected components analysis and whitespace extraction. Secondly, a heuristic filter is applied to identify non-text components. After that, using statistical method, we implement the recursive filter on multi-layer homogeneous regions to identify all text and non-text elements of the binary image. Finally, all regions will be reshaped and remove noise to get the text document and non-text document. Experimental results on the ICDAR2009 page segmentation competition dataset and other datasets prove the effectiveness and superiority of proposed method.

• The Journal of Asian Finance, Economics and Business
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• 제8권5호
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• pp.1-9
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• 2021

The purpose of this study is to examine the effects of economic uncertainty on MNC investment in Malaysia from 2009 to 2019 by employing an ARDL method. The results revealed that Economic Policy Uncertainty (EPU) has a positive association with the capital expenditures of Nestle, British American Tobacco, and Public Bank in the long run. In a similar period, the Gross Domestic Product (GDP) is positively significant with the capital expenditures of British America Tobacco and Heineken. However, inflation is negatively related to the capital expenditures of British America Tobacco and Heineken. Additionally, the exchange rate has a significant and negative relationship with the capital expenditures of Nestle and Petronas, while the ECT value is negative and significant in the short run, hence confirming that co-integration exists. In view of this, it is imperative that the government plays a prerogative role to support MNC operations, as MNCs foster the developing countries' economic development through facilitating full employment. This study sets to enhance the personal knowledge of those with a strong interest in the Malaysian financial market. As long as MNCs believe that the Malaysian market has the potential to grow, they will continue to invest for the benefit of the country.

• 공학교육연구
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• 제22권4호
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• pp.32-42
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• 2019

This study is aim to the effects of job satisfaction on the major satisfaction of science and engineering college students and also analyzed the mediating effects of future outlook of job and major relevance in career choice. To do this, structural equation modeling(SEM) and multi-group SEM were applied to data from 2016 Graduate Occupational Mobility Survey(GOMS). In the results of this study, the major satisfaction, future outlook of job and major relevance were positive effects on job satisfaction and the mediating effects of future outlook of job and major relevance were verified. And results of analysis according to gender difference, the coefficient of woman was smaller than man. Among major satisfaction had a positive effect on job satisfaction, job satisfaction fell for women who value their relevance to the major when choosing a job. Based on such results, universities need to further strengthen their role in helping them enhance their expertise through skills and learning about their majors.

• East Asian Economic Review
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• 제23권1호
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• pp.27-53
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• 2019

I employ search-and-matching to a multi-country and multi-sector Ricardian model with input-output linkages, trade in intermediate goods, and sectoral heterogeneity, in order to quantify the welfare effects from tariff changes. The paper shows that labor market frictions can be a source of comparative advantage in the sense that better labor market conditions contribute to lower cost in production. Labor market frictions play a critical role in determining the probability of exporting goods to trading partners, and interact with bilateral trade share, price, expenditures, etc. Unemployment and changes in unemployment rates due to tariff reductions contribute welfare changes across countries, implying that welfare effects based on quantitative trade models with full-employment are likely to be biased. I confirm the biased welfare effects by revisiting Caliendo and Parro (2015), who conduct an analysis of the welfare effects from the NAFTA from 1993 to 2005. I show that the welfare gap between theirs and mine has a positive correlation with changes in observed unemployment rates across countries. With the constructed model, I further conduct counterfactual exercises by asking what would happen if China's tariffs remain unchanged from 2006 to 2015. It turns out that there are mild welfare effects to trading partners in the world trading system.

• Advances in concrete construction
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• 제11권2호
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• pp.163-171
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• 2021

This paper studies the effect of using multi-scale reinforcement additives on mechanical strengths, damage performance, microstructure, and water absorption of cementitious composites. Small dosages of carbon nanotubes (CNTs) or polypropylene (PP) microfibers; 0.05%, 0.1%, and 0.2% by weight of cement; were added either separately or simultaneously into cement mortar. The experimental results show the ability of these additives to enhance the mechanical behavior of the mortar. The best improvement in compressive and flexural strengths of cement mortar reaches 28% in the case of adding a combination of 0.1% CNTs and 0.2% PP fibers for compression, and a combination of 0.2% CNTs and 0.2% PP fibers for flexure. Adding CNTs does not change the brittle mode of failure of plain mortar whereas the presence of PP fibers changes it into ductile failure and clearly enhances the fracture energy of the specimens. Scanning electron microscopic (SEM) images of the fracture surfaces highlights the role of CNTs in improving the adhesion between the PP fibers and the hydration products and thus enhance the ability of the fibers to mitigate cracks propagation and to enhance the mechanical performance of the mortar.

• International Journal of Computer Science & Network Security
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• 제22권4호
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• pp.17-26
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• 2022

Sensor Nodes play a major role to monitor and sense the variations in physical space in various real-time application scenarios. These nodes are powered by limited battery resources and replacing those resource is highly tedious task along with this it increases implementation cost. Thus, maintaining a good network lifespan is amongst the utmost important challenge in this field of WSN. Currently, energy efficient routing techniques are considered as promising solution to prolong the network lifespan where multi-hop communications are performed by identifying the most energy efficient path. However, the existing scheme suffer from performance related issues. To solve the issues of existing techniques, a novel hybrid technique by merging particle swarm optimization and game theory model is presented. The PSO helps to obtain the efficient number of cluster and Cluster Head selection whereas game theory aids in finding the best optimized path from source to destination by utilizing a path selection probability approach. This probability is obtained by using conditional probability to compute payoff for agents. When compared to current strategies, the experimental study demonstrates that the proposed GTPSO strategy outperforms them.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2488-2498
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• 2021

The wall film-wise condensation plays an important role in the heat transfer processes of heat exchangers, refrigerators, and air conditioner. In the field of nuclear engineering, steam condensation is often utilized in safety systems to remove the core decay heat under both transient and accident conditions. In particular, passive containment cooling system (PCCS), are designed to ensure containment safety under severe accident conditions. A computational fluid dynamics (CFD) scale analysis has been conducted to calculate the heat transfer rate of the PCCS. However, despite the increase in computing power, there are challenges in the long-term transient simulation of containment using CFD scale codes. In this study, a heat structure coupling between the CFD and system analysis codes was performed to efficiently analyze PCCS. In addition, the component unstructured program for interfacial dynamics (CUPID) was improved to analyze the condensation behavior of ternary gas mixtures. Thereafter, the condensation heat transfer on the primary side was calculated using the improved CUPID and CFD code, whereas that on the secondary side was simulated using MARS. Both the coupled codes were validated against the CONAN facility database. Finally, conjugate heat transfer simulations with wall condensation in the presence of non-condensable gases were appropriately performed.

• 품질경영학회지
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• 제50권3호
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• pp.407-424
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• 2022

Purpose: This study examines the relationship between the environment, society, and governance (ESG) perception of service providers and service quality by considering job satisfaction as a mediator in the Korean parcel delivery context. Methods: This study uses a multi-level analysis by incorporating organizational and individual levels of analysis. It employs a survey method for measuring the ESG perception of parcel delivery persons and service quality ratings from the Korean government. A hierarch regression analysis with 241 responses was used to test hypotheses. Results: The results of this study provide evidence that the ESG perception, particularly its social dimension, of parcel delivery persons is positively associated with service quality. This study also finds the positive effect of the ESG perception on job satisfaction. However, the mediating effect of job satisfaction between the ESG perception and service quality was not confirmed. Conclusion: This study presents significant implications for scholars and practitioners. Parcel delivery companies should implement relevant ESG activities and communicate them with their service persons to improve delivery service quality. The ESG perception of employees plays a critical role in the moment of truth in parcel service delivery to enhance customer satisfaction and service quality.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.70-75
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• 2002

The penetration potential of TIG welding in one single run is limited, though the process itself generates high quality welds with good weld cosmetics. This is one of the main reasons, which has contributed to its development in high duty applications such as those encountered in aeronautical, aerospace, nuclear & power plant applications. For these applications, stainless steels, titanium k nickel based alloys are most often used. As these materials remain very sensible to weld heat input k atmospheric pollution, stringent processing conditions are imposed. For example welding of titanium alloys requires argon shielding of weld zone and for 5 mm thick plates multi-pass runs & filler additions are required. This multi-run operation not only raises the welding cost, but also increases defect risks. In recent years, extensive interest has been raised by the possibility to increase weld penetrations through flux applications & the process is designated ATIG-activated TIG, or FBTIG-flux bounded TIG. The improved welding performance of such flux assisted TIG is related to arc constriction and surface tension effects on weld pool. The research work by authors has lead to the formulation of welding fluxes for stainless steels k titanium alloys with TIG Process. These fluxes are now commercialized & some applications in industry have already been carried out. FBTIG for aluminum has been proposed with silica application for AC mode TIG welding. The paper highlights the fundamentals of flux role in TIG welding and illustrates some industrial applications.