• International Journal of Automotive Technology
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• v.7 no.7
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• pp.785-793
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• 2006

The topic of this study is the control strategy of a mild hybrid electric vehicle (HEV) equipped with a continuously variable transmission (CVT). A brief powertrain and vehicle configuration is introduced followed by the control strategy of the HEV with emphasis on two key parts. One of them is an ideal operating surface (IOS) that operates the CVT powertrain optimally from the viewpoint of the tank-to-wheel efficiency. The other is a charge sustaining energy management to maintain the battery state of charge (SOC) within an appropriate level. The fuel economy simulation results of the HEV over standard driving cycles were compared with those of the baseline vehicle. Depending on the driving cycle, 1.3-20% fuel saving potential is predicted by the mild hybridisation using an integrated starter alternator (ISA). The detailed energy flow analysis shows that the majority of the improvement comes from the idle stop function and the benefits for electrical accessories. Additionally, the differences between the initial and the final SOC are in the range $-1.0{\sim}+3.8%$ in the examined cycle.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.641-646
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• 2009

This study examines the effects of water shortage on agricultural wages in Northwest Bangladesh. For this study, meteorological data including information on the monthly temperature, precipitation, wind speed, hour of sunshine and humidity of six weather stations have been utilized during the monitoring period from 1985 to 2005. With the objective to analyze water surplus and water deficiency, a simple soil-water balance model and the modified Penman formula were applied to the Northwest Bangladesh. The seasonality of Mann-Kendell trend statistics has been used to identify the spatial variation of water surplus and deficiency throughout the region. For micro level verification of the result, a detailed field survey has been conducted within the study area. The results showed that the values of the potential evapotranspiration estimated by the modified Penmen equation were negative for certain periods. In this instance, the water deficiency of the district of Rajshahi was observed significantly in the period of pre-monsoon and post-monsoon. The field study also verified that because of such deficiency in water, the agricultural scenario of the area was widely influenced which lead to less agricultural production and less economic benefits.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.149-157
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• 2004

A Piston assembly is very important because it directly receives the energy generated during combustion process. Surely, the friction and lubrication of piston ring pack do an important role in the performance and fuel economy of an engine. in fact, the friction loss in piston ring pack is the biggest portion to the whole engine friction. Therefore, the improvement of lubrication quality and friction loss in piston ring pack will be directly related with the improvement in the performance and fuel economy of an engine. Meanwhile, the oil consumption and blow-by gas through piston-cylinder-ring crevices have to be controlled as less as possible. In these two aspects, the study on the optimized design of piston ring pack has to be carried out. In this study, for the efficient design of piston ring pack, it is focused to develop a basic computer program that predicts the inter-ring pressure, the motion of ring and the blow-by gas through a crevice volume model between adjacent rings, and the oil film thickness and the friction computed by lubrication theories.

• Industrial Engineering and Management Systems
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• v.4 no.2
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• pp.198-206
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• 2005

The single sourcing policy, in which an automobile manufacturer purchases identical or similar parts from one supplier, has an advantage of scale economy. Meanwhile, multiple sourcing policy, which allows procuring similar parts from multiple suppliers, has benefits of dispersing risks and promoting competition among suppliers. This paper analyzes the procurement policies by presenting a model of the Japanese automobile parts trade. It concludes that maturity of technology involved should be taken into account besides above-mentioned factors which have traditionally been recognized. For parts produced using evolving technologies, the single sourcing enhances purchaser’s benefits because of the scale economy in learning process. In the meantime, multiple sourcing is more beneficial to the purchaser if the parts are based on mature technologies. In either policy, if the technology involved is evolving, motivating suppliers by returning a great part of cost reduction as a reward to them may eventually increase profit for the purchaser. The conclusion supports the situation where the number of suppliers is being cut down as the trend of modularization and system deliveries of parts progresses in the auto parts industry, and suggests that returning part of benefits to parts suppliers may be encouraged from the viewpoint of auto manufacturers’ own interest.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.1110-1116
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• 1993

A study on optimum operation performances of power efficiency, economy and exhaust emissions for a tractor was conducted. A mathematical model of multiple degree polynomial equation was applied to established the function of solid multiple parameter curves for specific fuel consumption (ge), cabon monoxide (CO) ,hydrcarbons (HC) and cabonaceous smoke (Rb). The optimum operation theorems for economy operation indicated by ge and for exhaust emissions described by Co , HC and Rb were obtained from analytical method and performance test data. The optimum operation theorems could exhibit optimum operation working points, curves, and regions. The optimum matching relations of engine speed and transmission parameters were analyzed by using computer simulation methods in accordance with the tractor specifications , actual farm working conditions in a typical drawbar pull work such as plowing , the optimum operation objective function, the ideal transmission ratio, practical gear shif ing positions and practical travel speed of the tractor TN55 medel. The results of the anlayzes indicated clearly that the optimum power efficient operation, energy saving and pollution reducing would be realized if the tractor would be operated according to theoptimum operation methods.

• Journal of Distribution Science
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• v.17 no.6
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• pp.15-23
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• 2019

Purpose - This study evaluates the effects of e-marketing communication on brand loyalty in the mobile communication market in Kosovo. given that no prior studies of this nature are found. It explores the relationships, between e-marketing communication, brand image and customer satisfaction, and their impact on the brand loyalty. Research design, data, and methodology - The research model of four constructs was developed. The data was collected via online surveys, 423 completed surveys from mobile subscribers were received. To test the relationship between the individual variables and multiple variables with the dependent variable several test were performed including data validity and reliability, bivariate correlation, simple linear and multiple regression analysis using stepwise method. Results - Positive significant effect of e-Marketing communication on brand loyalty, as well its significant effect on both brand image and customer satisfaction, which subsequently have significant impact on brand loyalty as it was confirmed by previous studies. Conclusions - The findings confirm that e-Marketing communication is key factor in building well perceived brand image, fostering customer satisfaction, and leading to customer commitment and loyalty towards brands of mobile operators in Kosovo.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.2
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• pp.35-42
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• 2018

In recent decades, financial crises in various countries have often been preceded by the rise in non-performing loans (NPLs) in the banks' asset portfolios. The increase in NPLs is proven to have adverse impact on the banking sector so that understanding the determinant of NPLs is immensely crucial to ensure the efficiency and soundness of the overall economy. This study aims to shed light on bank-specific factors that affect loan default problems in developing countries whose banking sectors play a major role in the overall economy. This study analyzes panel data sets of 36 commercial banks listed in the Indonesian Stock Exchange during the period 2008-2015. Applying fixed-effects panel regression model reveals that Indonesian banks' profitability and credit growth negatively influence the number of NPLs. Moreover, banks with higher profitability are proven to have lower NPLs because they can afford adequate credit management practices. Likewise, banks with higher credit growth evidently have lower NPLs in the sense that they demonstrate more specialized lending activity and thus have better credit management systems. These findings imply that, in order to lower loan defaults that can deteriorate banks' asset quality, banks should maintain their level of profitability and increase, rather than decrease, their credit supply to debtors.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.2
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• pp.43-51
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• 2018

We study the impact of economic policy uncertainty (EPU) of Asian four countries such as Korea, Japan, Hong Kong, and China on housing market returns in Korea. Also, we document the relationship between the EPU index of those four countries and the housing market including macroeconomic indicators in Korea. The EPU index of those four countries has significantly a negative effect on the housing purchase price index, housing lease price index in Korea. The EPU index in Korea and Japan has significantly a negative effect on the CPI. The EPU index in only Japan has significantly a negative effect on the PPI. The EPU index in Hong Kong and Korea has significantly a negative effect but the EPU index in China significantly has a positive effect on the stock price index in construction industry. The EPU index in only Korea has significantly a negative effect the stock price index in banking industry. This study shows the EPU index of the Korea has the negative relationships on the housing market economy rather than other countries by VECM. And this study has an important evidence of the spillover of several macroeconomic indicators in Korea for the EPU index of the Asian four countries.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12B
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• pp.1087-1098
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• 2006

This study is unlike common Input-Output Analysis in the point that both RAS and methods are applied to the dynamic Input-Output Model simultaneously. We have analyzed the propagation effects on the regional economy from the investment generated by u-City construction in Wha-sung and Dong-tan City. The main results of the study are as follows. The total induced effect on production according to u-City construction in Wha-sung and Dong-tan City is estimated about 2.9 times. On the other hand, u-City industry is appreciated as a industry which a forward linkage effect is very high while a backward linkage effect is not that high.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.11
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• pp.434-443
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• 2016

The evaporation of water from an aqueous solution is widely used in the food, desalination, pulp, and chemical industries. Usually, a large amount of energy is consumed in the evaporation process to boil off water due to atmospheric pressure. As a way of improving the energy efficiency of the evaporation process, the combination of multiple effect evaporation and thermal vapor recompression has been proposed and has become a successful technique. In this study, 4 multiple-effect falling film type evaporators for sugar solution are designed and the energy efficiency of the system is analyzed in response to the selection of the steam ejector position. Energy efficiency is increased and vapor is more compressed in the steam ejector as the Thermal Vapor Recompression (TVR) is arranged in the rear part of the evaporator system. A simplified 0-dimensional evaporator model is developed using non-linear equations derived from mass balances, energy balances, and heat transfer equations. Steam economy is calculated to compare the evaporation performance of the 4 proposed evaporators. The entrainment ratio, compression ratio, and expansion ratio are computed to check the ejector performance.