• Journal of the korean Society of Automotive Engineers
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• v.3 no.2
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• pp.18-26
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• 1981

The purpose of this paper is to study the possibility of practical use of gasoline-methanol mixed fuel as an alternative fuel of gasoline engines in the light of engine performances and harmful exhaust emissions as well as mixings and separations of the mixed fuels. When the methanol of 99.8% purity is mixed with super or regular gasoline available on the market today, the experimental results obtained without modifying carburetor in this study are as follows; 1.The separation ratio depends upon the gasoline-methanol mixing ratio only, regardless of fuel temperature and fuel additives for preventing separation of phase. 2.The critical absorption ratio is affected by the gasoline-methanol mixing ratio, its temperature and the quantity of fuel additives. 3.Concerning the distillation temperature, the initial point of all sorts of fuels is almost same,but 10% point and 35-60% point of mixed fuels are lower than those of gasoline only. 4.In case of throttle valve opening set, engine output using the mixed fuels is decreased compared to gasoline, but thermal efficiency is increased as a consequence of decreasing specific energy consumption. 5.In case of fixed load test, thermal efficiency is increased at low engine speed even under low part-load as well as under comparatively high part-load including full load. 6.CO and NOx emissions are reduced remarkably with the mixed fuels.

• Journal of KIBIM
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• v.7 no.2
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• pp.44-55
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• 2017

Recently, there has been a growing interest in the life cycle management field of buildings through the introduction of BIM. And as BIM application is expanded, BIM ordering guidelines and guidelines are becoming popular. Also, as diverse forms of buildings including super high-rise building have been generalized, attention to the importance of curtain walls that are advantageous for construction period shortening, building lighting and quality homogenization has been increasing. However, all BIM information from the design stage to the maintenance stage is not accumulated in stages. And the input information is not improved in proportion to the level of appearance of the BIM model. Also, current curtain wall designs rely heavily on curtain wall consulting firms or utilize accumulated data from existing processes. In this study, curtain wall components, shape and property information were derived by analyzing BIM guidelines and curtain wall construction standards to contribute to solving these problems. And the curtain wall smart BIM library which can be converted according to LOD(Level of Development) has been produced and its applicability has been verified. Through the library, curtain wall information can be systematically managed in the library from design to construction and maintenance. And the library will contribute to the expansion and activation of the BIM library market in the future.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.287-296
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• 2010

The purpose of this research is to analyze priority of the elderly user interface (UI) evaluation criteria based on user's lifestyle. Since the elderly population will occupy over 20% of the all Korean population in the near future, we need to know older users' needs and information because elderly users will be main customers in the super-aged society. This paper investigated the definition of elderly users and characteristics demographically, socio-economically, and physically/cognitively. A total of 238 questionnaires from older users were analyzed based on a segmentation table for the elderly developed by the previous study. According to factor analysis and cluster analysis, 6 types of lifestyle and 4 groups of the elderly users were classified, respectively. The priority of UI evaluation criteria for large electronic home appliances and mobile products was analyzed by analyses of variance (ANOVAs). The results indicated that the priority of (physical, emotional, and cognitive) UI criteria was significantly different among elderly users' lifestyles for both home appliances and mobile products. Consequently, the results of this study may help the company develop some competitive silver products and give higher satisfaction to the elderly users by suggesting different priority of UI evaluation criteria according to the target elderly group. The results may also contribute to revitalize national economy by significantly increasing senior market shares.

• Journal of the Korean Ceramic Society
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• v.48 no.2
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• pp.121-126
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• 2011

The study investigates the effects of a body that influences the nucleation and growth of crystal by experiment the application of zinc crystalline glaze to five of the most favorably used kinds of bodies sold in the market. As a result, in all bodies used in the test, willemite crystal is appeared on the surface and in the case of white porcelain, super white and white porcelain sculpture clay, beautiful crystals is developed. The reason that crystal does not grow and trickle down by sticking to the body in celadon clay and Sanchung clay is the large surface tension of glaze by ingredient CaO which is more often present compared to other bodies. In glaze, the ingredients $Al_2O_3$ and RO greatly influences the surface tension, and adhesion of the glaze and the body is completed by the glaze's power to stick, which is determined by the reaction of both the glaze and the body. However, in the case of Sanchung clay, the CaO in body reacts to the glaze, and glaze, on Sanchung clay, has tendency to run more compared with other bodies. It is supposed that this mechanism influences the growth of willemite crystal and the glaze's adhesion to the body.

• Journal of Internet Computing and Services
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• v.17 no.3
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• pp.129-136
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• 2016

Crucial aspects to successfully realizing the re-emergence of a contemporary and sustainable supercomputing community in South Korea will involve the devoted efforts and support from key government and R&D organizations. We suggest various supplementation plans regarding the roles of support for the statutory plan. This includes the committee and the plans which are often missing necessary support systems that help competent ministries to plan properly according to the missions of the research center. This dissertation suggests that adjustment in the HPC trends will depend upon exposing and correcting problems in the law as well as overall improvement of the law. Also, the total development of a super computing market is necessary. The results of these guidelines will create a spread of demand for supercomputing for national IT resource sharing, and will foster the development of supercomputer specialists worldwide. Other major end results include significant increases in research productivity and increased rates of product development.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.11
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• pp.3937-3954
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• 2014

With the increasing electricity consumption and the wide application of renewable energy sources, energy auction attracts a lot of attention due to its economic benefits. Many schemes have been proposed to support energy auction in smart grid. However, few of them can achieve range query, ranked search and personalized search. In this paper, we propose an efficient multi-keyword range query (EMRQ) scheme, which can support range query, ranked search and personalized search simultaneously. Based on the homomorphic Paillier cryptosystem, we use two super-increasing sequences to aggregate multidimensional keywords. The first one is used to aggregate one buyer's or seller's multidimensional keywords to an aggregated number. The second one is used to create a summary number by aggregating the aggregated numbers of all sellers. As a result, the comparison between the keywords of all sellers and those of one buyer can be achieved with only one calculation. Security analysis demonstrates that EMRQ can achieve confidentiality of keywords, authentication, data integrity and query privacy. Extensive experiments show that EMRQ is more efficient compared with the scheme in [3] in terms of computation and communication overhead.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.04a
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• pp.51-54
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• 2007

This study investigates the properties of paste and mortar from different types and forms of silica fume on cement binder for ultra high strength. Although most Silica Fumes distributed in the market fulfill the KS quality standard, each type showed different levels of loss of ignition. When evaluating cement binder for ultra high strength in a form of paste. Flow, viscosity and moving freely time show great difference depending on the Silica Fume's form and type of primary particle's dispersibility. The evaluation of Silica Fume's dispersibility can be possible with the paste test since there is a high correlation of flow quality between paste and mortar. The compressive strength when using Silica Fume was correlated to the SiO2 content. Synthetically, selecting Silica Fume with the most the ideal primary particle is the key to optimizing the formation for cement binder for ultra high strength.

• Journal of Information Technology Services
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• v.15 no.4
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• pp.175-191
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• 2016

This paper investigates changing processes of new product development (NPD) systems. In order to continuously develop first-class products, world wide super-class products and hit products, R&D (Research & Development) must be competitive. Firms must achieve competitiveness in terms of quality and cost by launching new products. Most films focus on improving effectiveness and efficiency of NPD process. However, sometimes, they face to the critical challenge of transforming NPD processes entirely reflecting dramatic change of their core products. Transforming of NPD process is difficult in that it involves technological and organizational changes in marketing, R&D, Engineering and manufacturing systems. The purpose of this paper is to shed light on processes and factors affecting successful transformation of new product development systems. We present a case study on the changing processes of S company's NPD process. S company has changed new product development systems successfully from a major IT equipment supplier to an automotive supplier. Empirical results show successful changes of 10 core NPD processes from understanding the market and customers process to after sales process. In case of transformation of NPD, adaption of attribute of business is crucial for success factors in the process innovation. This paper shows the bridging the gap between IT and automotive industrial dynamics and growth through adaption of two processes in the NPD.

• The Journal of Information Technology
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• v.3 no.3
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• pp.39-55
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• 2000

Internet Trade is the new type of business transaction, which sells and advertises the product and services by using the Internet, which is spreaded rapidly to the world. Under these circumstance, our country should discuss the proper position and role as the center in the trade amount in the world trade market, and face the irresistible changes of trade environment. First, in the institution and legal aspect. Second, the price payment system of the internet trade. Third, the so-called infra construction, the physical sector for activating the internet trade, the comprehensive plan of super-highway information communication net work by the government authorities is expected to be promoted. There is no perfect solution that internet trade could be completely done in front of monitor and will be solved one by one along with the development of electronic commerce. At last, the government's and industry's joint positive concern and participation in the rapidly changing new world trade trends of internet trade is expected fit for our position in the world.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.15 no.3
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• pp.172-179
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• 2015

Because of the development of computers and high-technology applications, all devices that we use have become more intelligent. In recent years, security and surveillance systems have become more complicated as well. Before new technologies included video surveillance systems, security cameras were used only for recording events as they occurred, and a human had to analyze the recorded data. Nowadays, computers are used for video analytics, and video surveillance systems have become more autonomous and automated. The types of security cameras have also changed, and the market offers different kinds of cameras with integrated software. Even though there is a variety of hardware, their capabilities leave a lot to be desired. Therefore, this drawback is trying to compensate by dint of computer program solutions. Image processing is a very important part of video surveillance and security systems. Capturing an image exactly as it appears in the real world is difficult if not impossible. There is always noise to deal with. This is caused by the graininess of the emulsion, low resolution of the camera sensors, motion blur caused by movements and drag, focus problems, depth-of-field issues, or the imperfect nature of the camera lens. This paper reviews image processing, pattern recognition, and image digitization techniques, which will be useful in security services, to analyze bio-images, for image restoration, and for object classification.