• 한국자동차공학회논문집
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• 제15권1호
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• pp.16-22
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• 2007

Fuel efficiency is one of the major issues in regard to energy and environment. As customers desire more comfortable vehicles, increase of accessory traction force is necessary. Air conditioning system (ACS) consumes the biggest traction force among accessories, especially during summer. This means ACS is the primary object deteriorating fuel economy among accessories. Since direct measurement of traction force and fuel consumption in practical vehicle is difficult, comparison analysis is taken between vehicle with and without ACS working. For this comparison, real time measurements are carried out to know ACS traction force and fuel consumption. As a result of the comparison, a vehicle without ACS operation was 15.92% superior to a vehicle with ACS operating. It could be used as a fundamental material for improvement ACS for better fuel efficiency.

• The Journal of Asian Finance, Economics and Business
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• 제10권1호
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• pp.49-55
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• 2023

Business is an important entity in every economy with its role in job creation, budget contribution, and national output. It can be said that enterprises are also one of the leading units that play a key role in implementing digital transformation, grasping science and technology, and improving labor productivity. Developing a team of enterprises that are both strong in quantity and strong in quality is an urgent requirement in many countries, including Vietnam. Vietnam is a developing country and home to many textile and garment enterprises operating due to the advantages of cheap labor and a large market, the textile and garment industry is capable of creating many jobs for the economy. Studying the factors affecting corporate financial performance across 250 textile and garment enterprises in Hanoi capital and Bac Ninh province, the research results show that when enterprises have the ability to mobilize capital, the cost is cheap, appropriate, and optimal, most businesses often achieve higher business efficiency and financial performance. In contrast, enterprises that are difficult to raise capital in the economy often achieve low financial efficiency and financial performance. The study also confirms the role of human capital in enterprises, enterprises with high human capital often achieve high profits.

• 유통과학연구
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• 제15권8호
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• pp.75-86
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• 2017

Purpose - The online-to-offline (O2O) business model has brought considerable changes to the traditional Chinese business model. The main difference between O2O and pure online consumption is that O2O offers a richer experience and word-of-mouth. it is easier to trigger online word-of-mouth. However, few scholars have been concerned about the impact of experiential value on customer satisfaction and online word-of-mouth (e-WOM) in the study of O2O. This study takes the O2O business model in China's catering industry as its research object and uses structural equation modelling to analyze the impact of online and offline experiential values on customer satisfaction and e-WOM. Research design, data, and methodology - According to previous researches, consumer experiential value is mainly divided into return on investment (economy and efficiency), service excellence, playfulness and aesthetics. According to the characteristics of O2O in China's catering industry, this study divides the online experience value into efficiency and economy (return on investment). The offline part is divided into return on investment (economy and efficiency), service excellence, playfulness and aesthetics. Using a web-based survey, we collected 303 valid samples. Structural equation modelling was used to create the research model. Results - The results show that efficiency (online) and service excellence (offline) have a significant effect on customer satisfaction. Economics (online) and playfulness (offline) have a positive impact on customers' e-WOM. In addition, the higher the customer satisfaction, the greater the positive impact on the spread by word of mouth. However, aesthetic(offline) and return on investment(offline) have no significant impact to customer satisfaction and e-WOM. Conclusions - The study findings show that the key to boost customer satisfaction in the catering industry is to improve product quality and service. Although traditional competitive strategies such as online discount have been questioned by many scholars about their decreasing effectiveness, they are indispensable means to attract online traffic and trigger e-WOM. The traditional enterprises can reconstruct traditional business processes through the O2O model to effectively improve customer satisfaction and word of mouth by improving the experiential value of economy and efficiency. Additionally, it can be used as the natural advantages of online communication to induce customers to engage in word of mouth and attract more potential customers.

• 한국자동차공학회논문집
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• 제18권2호
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• pp.7-13
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• 2010

To satisfy the needs on fuel economy and engine performance, continuous variable valve lift systems are applying to engines. In the CVVL system, fuel economy can be improved by reducing pumping loss during the induction process, and engine performance can be also improved by controlling volumetric efficiency and the residual gas fraction. Because the residual gas fraction directly affects volumetric efficiency, engine performance, combustion efficiency and emissions in SI engines, controlling residual gas fraction is one of the important things in engine development process. This analysis investigates the residual gas fraction and volumetric efficiency with changes of intake valve lifts and intake valve timings. In this study, unsteady state solutions were solved during exhaust and induction processes. Results show variation of the residual gas fraction and volumetric efficiency by changing intake valve timing and lift. Decreasing intake valve lift leads to increase the residual gas fraction and to decrease volumetric efficiency.

• 한국응용과학기술학회지
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• 제35권3호
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• pp.667-675
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• 2018

점차 강화되는 배출가스 규제와 적은 연료로 많은 거리를 주행할 수 있는 고효율 자동차에 대한 요구로 에너지소비효율에 대한 관심이 점차 늘어나고 있다. 국내의 에너지소비효율은 도심주행모드와 고속도로 모드를 주행하여 복합연비로 산정하고 5-Cycle 보정식을 이용하여 최종 에너지소비효율을 표시하고 있다. 에너지소비효율의 경우 카본발란스법에 의하여 산출되는데 이때 배출가스에 의해 계산이 됨에 따라 연소에 사용되는 연료는 자동차 성능과 에너지소비효율에 매우 중요한 역할을 하게 된다. 자동차 연료의 경우 국내에서는 석유 및 석유대체연료 사업법 품질기준에 따라 국내에 유통되고 있는데 정유사의 정제 방법이나 원유에 따라 품질 기준 내에서 물성 차이를 보일 수 있다. 일정 품질기준을 정하고 있음에 따라 연료별 큰 차이는 나지 않을 것으로 보이나 자동차의 성능에는 영향을 미칠 수 있어 그에 따른 연구가 필요한 실정이다. 따라서, 본 연구에서는 시중에서 유통되고 있는 연료 중 여름철에 판매되는 경유를 정유사 직영점을 통해 구매하였으며, 각 시료별 물성을 분석하고 그에 따른 에너지소비효율을 측정하였다. 에너지소 비효율의 경우 현행 경유 자동차의 에너지소비효율 산정식과 휘발유 에너지소비효율에서 사용되는 산출식을 이용하여 물성 적용에 따른 변화를 살펴보았다. 그 결과 시료별 밀도는 최대 약 0.9%의 차이를 보였으며, 순발열량은 1.6%의 차이를 보였으며, 현행 에너지소비효율 산출 결과에서는 도심모드에서 약 1%, 고속모드에서 1.4% 차이를 보였다. 휘발유 산출식을 이용한 산출에서는 현행 에너지소비효율 산출때 보다 약 6%정도 낮은 수치를 보였으며, 각 시료별 에너지소비효율은 최대 도심과 고속에서 최대 약 1.4%의 차이를 보였다.

• 한국의류학회지
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• 제41권3호
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• pp.548-555
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• 2017

This study focuses on how clothing can increase in the age of the shared economy and as an alternative to the capitalist economy of the 21st century. This study investigates how infants and children use clothes as they undergo many changes based on physical growth, identifies use and disposal methods for surplus clothing from the perspective of a shared economy and explores plans to foster an environment for the healthy use of clothes. The objectives of this study are as follows. First, identify the need for new clothes based on physical changes in the human body; second, propose an alternative to permanent disposal by making used clothes appropriate for temporary disposal (renting and leasing). In sharing services, the condition and quality of the product were found to be the most important factors. The condition and quality of the product (70.0%) were the most important factors in sharing services. The sharing services for clothes and goods of infants and children could become popular quickly if there was a reliability guarantee offered by such sharing services. In addition, providing trial services and aggressive publicity for sharing services is urgent for the expansion of opportunities for general consumers.

• International Journal of Computer Science & Network Security
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• 제23권9호
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• pp.29-36
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• 2023

Blockchain is an emerging technology that is used to address ownership, centrality, and security issues in different fields. The blockchain technology has converted centralized applications into decentralized and distributed ones. In existing sharing economy applications, there are issues related to low efficiency and high complexity of services. However, blockchain technology can be adopted to overcome these issues by effectively opening up secure information channels of the sharing economy industry and other related parties, encouraging industry integration and improving the ability of sharing economy organizations to readily gain required information. This paper discusses blockchain technology to enhance the development of insurance services by proposing a five-layer decentralized model. The Najm for Insurance Services Company in Saudi Arabia was employed in a case study for applying the proposed model to effectively solve the issue of online underwriting, and to securely and efficiently enhance the verification and validation of transactions. The paper concludes with a review of the lessons learned and provides suggestions for blockchain application development process.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.429-436
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• 2005

In this paper, operation algorithms are evaluated for a fuel cell hybrid electric vehicle (FCHEV). Power assist, load leveling and equivalent fuel algorithm are proposed and implemented in the FCHEV performance simulator. It is found from the simulation results that the load leveling algorithm shows poor fuel economy due to the system charge and discharge efficiency. In the power assist and equivalent fuel algorithm, the fuel cell stack is operated in a relatively better efficiency region owing to the battery power assist, which provides the improved fuel economy.

• International Journal of Automotive Technology
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• 제5권4호
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• pp.287-295
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• 2004

A performance simulator for the fuel cell hybrid electric vehicle (FCHEV) is developed to evaluate the potentials of hybridization for fuel cell electric vehicle. Dynamic models of FCHEV's electric powertrain components such as fuel cell stack, battery, traction motor, DC/DC converter, etc. are obtained by modular approach using MATLAB SIMULINK. In addition, a thermodynamic model of the fuel cell is introduced using bondgraph to investigate the temperature effect on the vehicle performance. It is found from the simulation results that the hybridization of fuel cell electric vehicle (FCEV) provides better hydrogen fuel economy especially in the city driving owing to the braking energy recuperation and relatively high efficiency operation of the fuel cell. It is also found from the thermodynamic simulation of the FCEV that the fuel economy and acceleration performance are affected by the temperature due to the relatively low efficiency and reduced output power of the fuel cell stack at low temperature.

• 한국분무공학회지
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• 제16권2호
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• pp.97-103
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• 2011

The electronically controlled diesel engine was converted to dual fuel engine system. Test engine was set up for investigating the power output, thermal efficiency and emissions. ND 13-mode tests were employed for the engine test cycle. The emission result of dual fuel mode meets Euro-4 (K2006) regulation and the engine performance of dual fuel engine was comparable to the performance of diesel engine. To estimate economical efficiency, test vehicles have been operated on a certain driving route repeatedly. Fuel economy, maximum driving distance per refueling and driveability were examined on the road including free ways. Developed vehicle can be operated over 500 km with dual fuel mode and shows 80% of diesel substitution ratio. Driveability of dual fuel mode is similar with that of diesel mode.