• 센서학회지
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• 제28권6호
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• pp.414-419
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• 2019

An ultrasonic based magnetostrictive position sensor (MPS) provides an indication of real target position. It determines the real target position by multiplying the propagation speed of ultrasonic wave and the time-of-flight between the receiving signals; one is the initial signal by an excitation current and the other is the reflection signal by the ultrasonic wave. The propagation speed of the ultrasonic wave depends on the temperature of the waveguide. Hence, the change of the propagation speed in various environments is a critical factor in terms of the positioning accuracy in the MPS. This means that the influence of the changes in the waveguide temperature needs to be compensated. In this paper, we presents a novel way to improve the positioning accuracy of MPSs using temperature compensation for waveguide. The proposed method used the inherent measurement blind area for the structure of the MPS, which can simultaneously measure the position of the moving target and the temperature of the waveguide without any additional devices. The average positional error was approximately -23.9 mm and -1.9 mm before and after compensation, respectively. It was confirmed that the positioning accuracy was improved by approximately 93%.

• 한국분말재료학회지
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• 제15권3호
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• pp.196-203
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• 2008

The densification behavior of Al-20Si-5.5Fe-1.2Mg-0.5Mn powders was investigated through micro-structure analysis of sintered specimens. The specimens sintered in vacuum or in high purity (99.999%) nitrogen showed porous near-surface microstructures. The densification of near-surface part was enhanced by means of ultra-high purity (99.9999%) nitrogen atmosphere. The relationship between slow densification and oxide surfaces of Al alloy powders was discussed. And the effects of Mg addition, nitrogen gas, and humidity on densification were discussed. In addition, the rapid growth of primary Si crystals above the critical temperature was reported.

• 한국항공우주학회지
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• 제34권10호
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• pp.92-98
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• 2006

2006년에 발사된 다목적실용위성은 자세제어 등에 필요한 추력과 모멘트를 발생하기 위해 NASA의 1lbf급 단일추진제 표준 추력기인 MRE-1을 사용하고 있다. 단일추진제 추력기는 추진제와 촉매와의 열분해 반응에 의해 추력을 발생시키는데 이때 발생되는 분해열은 상대적으로 온도가 낮은 주변 구조물 및 전자부품으로 과도한 복사열전달을 발생시키는 열원이 된다. 따라서 추력기와 타 부품 사이에 과도한 복사 열전달을 방지하기 위해서는 복사 열차폐막이 필요하다. 본 논문에서는 열차폐막의 설계/해석 및 제작 등 전반적인 개발 과정에 대해 설명하였다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2000년도 춘계 학술대회 및 국제 감성공학 심포지움 논문집 Proceeding of the 2000 Spring Conference of KOSES and International Sensibility Ergonomics Symposium
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• pp.212-217
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• 2000

The purpose of this study was to develop a design process for a functional and sensible brassiere for muddle - aged women. As a methodology, an engineering design process QFD (Quality Function Deployment) was adopted to translate the consumer's needs into product design parameters. the customer needs for the wear comfort of brassieres were extracted from a survey of 100 women aged 30 - 40. To select which items were critical and which could be traded off for other attributed or benefits. the importance ratings for the customer needs were determined. Customer needs were translated into technical language by various physical test methods and wear tests. The customer competitive assessment was generated by wear tests of 10 commercial brassieres under controlled environmental conditions of 28${\pm}$1$^{\circ}C$, 65${\pm}$3% RH. The relationship matrix between the customer needs and the means of delivering the needs was developed. Using the QFD methodology, design elements for developing a brassiere for middle-aged women could be analyzed and organized efficiently.

• 한국실내디자인학회논문집
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• 제23권5호
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• pp.41-50
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• 2014

In relation to spatial expression, the remediation theory of Jay David Bolter & Richard Grusin shows a sufficient possibility of providing extended idea and experience through the space of critical representation. The remediation theory discussed in the scope of new media says about the existence method and the development process of media through immersion into media and awakening, and one attribute of remediation which aims at the extension of another realistic experience and recognition through various media, contains common denominators which display diversity and complexity of installation space, and use the audience as expression elements. Therefore, this study aims to apply the remediation theory in order to interpret space using more diverse and multisensory expression methods. For achieving this purpose, this study found the connection among characteristics of hypermediacy which is an axis of installation and remediation theory, and analyzed diverse cases regarding installation space and characteristics of hypermediacy, depending on external aspects of form and expression and internal aspects of experience and cognition. The method of hypermediation expression in installation space converts the recognition about the basic custom of new experience, space and representation. This means that the logic of remediation could approach space by leading to more extended form and recognition. In conclusion, the characteristics of space and the possibility of extended expression revealed in the relationship between installation space and hypermediacy logic would provide another developmental significance for research on space design.

• 한국안전학회지
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• 제27권5호
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• pp.203-210
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• 2012

Traffic accident risk of young drivers(less than 25) is reported to have 8 times as high as that of middle aged drivers(between 30 and 49). Despite the rise of traffic accident risk, few have been attempted to take a look into driving characteristics of young drivers. The purpose of this paper is to analyze age-specific risks of young driver by means of database of insurance and vehicle inspection, thereby collecting data such as age, vehicle mileage, injuries and so on. We conducted Data-Mining(CART) and Portfolio analysis according to age groups(every 10 years). The conclusions which can be drawn from this empirical study are as follows: (1) Despite the fact that young drivers have low vehicle mileage, the rate of fatality is relatively high. (2) Being concerned of vehicle mileage, 24,000km of driving experience is thought to be critical in differing in fatality rate. Having annual average mileage fewer than 24,169 km, accident frequency is relatively lower than that exceeding 24,169 km(1,571 cases). Backed upon these, some recommendations about driver's license system for young driver to improve are given.

• 경영과학
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• 제19권2호
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• pp.1-23
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• 2002

It has been considered as a means for sustaining a competitive advantage for companies to build and maintain long-term relationships with customers. It is without any doubt that many companies have tried to initiate Customer Relationship Management (CRM). For the effective management of customer relationships, it is critical that they acquire. share and use customer information and knowledge. In this paper, we deduced 9 important factors affecting the qualify of customer information and knowledge from the literature reviews on CRM, and developed the questionnaire to measure these factors. The factors are again categorized into organizational system, employees and IT. We analyzed data collected from 30 companies in service industries such as the finance. distribution and communication industries. The result of data analysis demonstrates that the employees' analytical shills and appraisal and reward systems are closely related to the quality of customer information, and analytical skills and IT support for communications with customers are associated with the quality of customer knowledge. implications of findings and future research directions are discussed.

• 산경연구논집
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• 제11권10호
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• pp.39-48
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• 2020

Purpose: Management of water is a crucial issue globally and is becoming more critical due to climate change. The purpose of this study is to explore water resource management by considering price and water usage based on river basins and to suggest more efficient residential water demand management in South Korea. Research Design, data, and methodology: This study applied data of water usage and water price of 15 regions in four major river basins by considering up and downstream locations from 1997 to 2017 collected by Ministry of Environment in Korea. This study applied regression analyses, ANOVA, and 2-Way ANOVA to verify its claims. Results: The results found that effects of price on water usage showed significant in many cities. The results also showed that means of water usages differ based on location (upstream and downstream) and river basins. Conclusion: The findings provide important policy and management implications for the improvement of water resource management in terms of demand. The results also indicate that water price should be reconsidered by comparing water price levels with those of OECD countries. Furthermore, the results imply that water management in Korea needs to improve in terms of supply to cope with climate change.

• Architectural research
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• 제20권2호
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• pp.35-43
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• 2018

This article explores the complex modes of experiencing the modern city that are engaging and disengaging by nature, which thus negates any simple ways of understanding what it means by 'the urban' in a Manichean comparison. What follows is an in-depth case study of Gordon Matta-Clark's 1976 film titled City Slivers. Influenced by the countercultural practices prevalent in the 1960s and 1970s, Matta-Clark produced a number of works roughly grouped together under the rubric of "building cuts." Among many others, City Slivers is distinctive among Matta-Clark's extensive cutting projects, in the sense that he actively utilizes film as a primary expressive medium and poetically reassembles fragmentary images of cityscape in order to bring forth an alternative urban scenario where the tension between institution-bound urbanization and dispersed daily urban practices is highlighted. Instead of simply being critical against the changing urban conditions of Manhattan in the 1970s, Matta-Clark aims to actively grasp ambivalent instances of urban life that are at once attractive and alienating, thereby excavating the subconscious terrain of contemporary urbanism that is prevalent but often dismissed over glamorous urban projects.

• 한국농공학회논문집
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• 제54권1호
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• pp.1-9
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• 2012

This study aims to assess the mobile information technology as an alternative means for managing information of irrigation facilities. Traditional irrigation facility management which is operated manually has faced to critical limitations, such as delayed and loss in data handling and facilities misidentification. Real time download, collection, and update the information about the irrigation structure conditions in terms of operation and maintenance can provide a better support of the management efforts. Thus this study suggested mobile information technology using RFID (Radio Frequency IDentification) and QR (Quick Response) code for real time information management of irrigation facilities. This paper describes the applications and implementation results of real-time mobile technology for the field information communication of the irrigation facilities. The system was tested in I-dong irrigation districts in Gyounggi-province, Korea and the assessment of operability demonstrated beneficial usability for inspection of agricultural irrigation facilities in the irrigation district. The tests showed that RFID was preferred method expected to improve operability although these had some limitation. The mobile technologies are expected to increase efficiency and effectiveness of irrigation facilities management.