• Journal of Drive and Control
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• v.17 no.3
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• pp.47-56
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• 2020

As a shift control of automatic transmission was managed with the electronic control unit (ECU), shift quality which is a measure of shift shock during gear change has markedly improved. However, the initial clutch pressure control of the clutch filling phase should continue to rely on the predetermined control input since the input and output speeds are unchanged until the shifting process attains the inertia phase. It is critical to minimize the clutch response time and control the clutch pressure accurately at the end of clutch fill to achieve quick shift response and smoothness. Advanced transmission companies have adopted an auto calibration method which establishes the databases for the clutch piston fill-up attributes and the frictional characteristics of the disks. In this study, a distinctive auto calibration algorithm for forklift transmission under development is proposed and verified with the real-vehicle test. The experimental calibration results showed consistent turbine dynamics at the initial stage of shifts with the properly calibrated clutch-fill control parameters. By using this technique, it is necessary to finalize the shift control for the various operation conditions.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.04a
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• pp.94-97
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• 1997

The December 13, 1996 Yeongweol earthquake of magnitude 4.5 was felt almost everywhere in southern part of the Korean Peninsula and Cheju Island, even though not feld in Tsushima Island at other places in Japan near to Korea. Production lines of semiconductor disk in electronic engineering companies of Gumi manufacturing complex were seriously affected by the shake of this earthquake. Total 17 earthquakes of magnitude 4 or above occurred within the area of 50km radius from Yeongweol in the period from the year 1400 to 1996. This group of earthquakes includes 12 events of magnitude 5.0 or above and 3 events of magnitude 6.0 or above. Among these events, 13 earthquakes are historical events of years 1400-1904. Most of them occurred in 15-16 centuries. The February 21, 1596 Jungseon-Pyeongchang event of magnitude 6.5 is the largest one up to now in the area. There are four instrumental earthquakes (years 1905-1996) of magnitude 4.0 or above in this area. An earthquake of magnitude 4.4 occurred on 5th of November, 1919 at almost the same place as the December 13, 1996 earthquake of magnitude 4.5. Thus this event is preceded with the previous one by 77 years.

• Journal of the Korea Safety Management & Science
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• v.17 no.4
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• pp.335-342
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• 2015

The increasing interests on patents have led many individuals and companies to apply for many patents in various areas. Applied patents are stored in the forms of electronic documents. The search and categorization for these documents are issues of major fields in data mining. Especially, the keyword extraction by which we retrieve the representative keywords is important. Most of techniques for it is based on vector space model. But this model is simply based on frequency of terms in documents, gives them weights based on their frequency and selects the keywords according to the order of weights. However, this model has the limit that it cannot reflect the relations between keywords. This paper proposes the advanced way to extract the more representative keywords by overcoming this limit. In this way, the proposed model firstly prepares the candidate set using the vector model, then makes the graph which represents the relation in the pair of candidate keywords in the set and selects the keywords based on this relationship graph.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.47
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• pp.239-260
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• 2010

The purpose of this study would like to investigate the critical success factors of the e-procurement which means on-line purchase of goods and services for organizations. This action represents one of the largest expense items in a firm's cost structure. In order to draw CSFs of e-procurement system, we have surveyed questionnaire to the related firms. The basic variables used in this survey are taken from many precedent researches in relation to the e-procurement. On the other hand, the research data is collected from companies which had used the MRO e-marketplace. Through factor analysis of those data, four-factor resulted as follows: (1) factor one suggests the rationalization of the firm's management of its suppliers; (2) factor two calls for redesigning affected business processes and influencing end-user/employee procurement-related behaviors; (3) factor three refers to carefully orchestrating an e-procurement technology planning process with one's suppliers and using intelligence in designing the software and mining the data it produces; and (4) factor four relates to selecting an e-procurement solution and/or simultaneously participating in a number of electronic environments supporting e-procurement. In conclusion, these four factors are regarded as critical success factors for the application of e-procurement system and then suppliers should take care the effective planning of e-procurement structure.

• Proceedings of the Korea Association of Information Systems Conference
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• 2004.11a
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• pp.431-443
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• 2004

Many e-Learning companies are incorporated for the last five years, but most of them are failed or merged by the other company. The main reasons are the absence of competitive strategies and recognition of critical success factors. There are many researches on the critical success factors of Information System (IS) and Electronic Commerce (EC) . We derived e-Learning success factors from the previous IS and EC researches. We classified the success factors into five dimensions, (1) contents management, (2) learner management, (3) business strategy, (4) organizational support and ability, (5) learning management system (LMS), and each dimension has 9 or more success factors measurement items. We surveyed the perceived importance of the success factors from the manager of South Korea e-Learning firms. The paper categorized the items into two or more factors for each dimension by the exploratory factor analysis. Finally, we conducted one-way ANOVA for each success factors by the business model. As a result, there is different importance level for each success factors by the business model. We concluded that each e-Learning company needs different strategies to their business model.

• Journal of Navigation and Port Research
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• v.42 no.2
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• pp.97-106
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• 2018

Despite the development of safety measures and improvements in preventive systems technologies, maritime traffic accidents that involve ships carrying hazardous and noxious substances (HNS) continuously occur owing to increased amount of HNS goods transported and the growing number of HNS fleet. To prevent maritime traffic accidents involving ships carrying HNS, this study proposes an intuitive route risk assessment technique using risk contours that can be visually and quantitatively analyzed. The proposed technique offers continuous information based on quantified values. It determines and structures route risk factors classified as absolute danger, absolute factors, and influential factors within the assessment area. The route risk is assessed in accordance with the proposed algorithmic procedures by means of contour maps overlaid on electronic charts for visualization. To verify the effectiveness of the proposed route risk assessment technique, experimental case studies under various conditions were conducted to compare results obtained by the proposed technique to actual route plans used by five representative companies operating the model ship carrying HNS. This technique is beneficial not only for assessing the route risk of ships carrying HNS, but also for identifying better route options such as recommended routes and enhancing navigation safety. Furthermore, this technique can be used to develop optimized route plans for current maritime conditions in addition to future autonomous navigation application.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.6
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• pp.48-54
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• 2012

In recent years, developments in the semiconductor and electronic industries have brought a rapid increase in the use of large size silicon. However, for many companies, it is hard to produce 400mm or 450mm wafers, because of excesive funds for exchange the equipments. Therefore, it is necessary to investigate 300mm wafer to obtain a better efficiency and a good property rate. Polishing is one of the important methods in manufacturing of Si wafers and in thinning of completed device wafers. This research investigated the surface characteristics that apply variable machining conditions and Taguchi Method was used to obtain more flexible and optimal condition. In this study, the machining conditions have head speed, oscillation speed and polishing time. By using optimum condition, it achieves a ultra precision mirror like surface.

• Management & Information Systems Review
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• v.4
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• pp.1-28
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• 2000

CALS(Commerce At Light Speed)/EC(Electronic Commerce) is drawing considerable interest as strategic part of efforts for computerization of the government and companies and for industry-wide innovation, using Internet and information superhighway that is widely expanding world-wide with the development of computers and information communication technology. In the current industry infrastructure, standardization is difficult but very important among the parties that want to share the added value, as external environmental components increase since the advent of computers. However, information security technology is not permitted to be exported in light of national interest or high amount of royalty should be paid. Moreover, if we cannot fully analyze the international standard and imported technology in order to verify the safety of using them, domestic information can be exposed according to the desire of the country exporting the technology. In particular, information security technology should be developed by ourselves, considering technology Protection and export Prevention Policies of foreign countries. Therefore, this paper presents information security technology and standardization trends for several application fields regarding CALS/EC implementation in our and foreign countries. This paper also analyzes such trends and proposes strategic direction for standardization suited for domestic environment.

• Journal of the Korea Society of Computer and Information
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• v.20 no.2
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• pp.197-208
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• 2015

Pharmaceutical companies over the world are exposed to risks of lessened sales and negative impact on corporate image due to circulation of counterfeit drugs, which eventually threatens safety of patients. thus, in order to eradicate distribution of counterfeit drugs, many countries are taking initiatives to legalize and set serialization through e-Pedigree, which is based on RFID technology or barcode system to track and trace distribution of drugs from point of manufacturing to usage. therefore, this study contemplates domestic and international management system of medical drugs and suggests application methods of e-Pedigree based on RFID technology that promotes safety of patients and distribution of drugs.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.5
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• pp.823-834
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• 2020

In the past, when the personal information leakage incident of the three card companies, the computer program development was followed by the same strict electronic financial supervision regulations as the operating environment. However, when developing a computerized program, the application data is being verified with the integrity of the test data being compromised because the identification of the scope of conversion of the test data associated with the application is unclear. Therefore, in this paper, we proved by presenting a process and algorithm for selecting a range of sufficient test data conversion targets associated with a specific application.