• Journal of Digital Convergence
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• v.18 no.6
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• pp.255-269
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• 2020

This paper aims to analyze the factors influencing consumer's choice of smartphone purchase channel in multichannel environments. Recently, smartphone purchase channels are becoming more complex and diverse. A smartphone with a short purchase cycle is a product applying advanced technology, the research of this topic would be significant. The major findings of this study are as follows. First, depending on the consumer's shopping orientation, the consumer group was classified into three groups of preference 1. Active shopping, 2. Convenient shopping, and 3. Rational shopping. Second, it was analyzed that the consumer's shopping orientation influenced the decisions of the information search channel and the purchase channel. Third, there was a significant difference between the search and purchase channels in the three groups. Finally, in the channel experience, there was a significant difference in price satisfaction by group. The results of these studies are expected to provide practical implications for establishing a customized multi-channel strategy. This study provides a desirable model for research on smartphone purchase channels.

• Journal of Korea Water Resources Association
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• v.44 no.11
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• pp.903-913
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• 2011

In this paper important factors in determining improvement priorities for water pipes were categorized into the effects of a pipe failure to entire pipe network and the characteristics of individual pipe. Subsequently, mathematical models that can quantify these factors were developed using the Fuzzy techniques. The effects of a pipe failure to entire pipe network and the characteristics of individual pipe that were estimated byFuzzy techniques were coined as Fuzzy Importance Index and Fuzzy Characteristic Index, respectively. The Fuzzy Characteristic Index was further categorized into Fuzzy Deterioration Index and Fuzzy Difficulty Index. Considerations were given to applying weights to specific factors in the developed model depending on the circumstances of model applications. To provide an example of the methodology an example pipe network, Net3, of the EPANET program was used. The Fuzzy Importance Index (FII) and Fuzzy Deterioration Index (FDI) were calculated for the Net3 network by considering the hydraulic effects of a pipe failure on the entire pipe network and the pipe deterioration as one of the individual pipe characteristics. Subsequently, the improvement priorities of the pipes in the Net3 pipe network were established based on the FII and FDI.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.10a
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• pp.73-77
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• 1996

정보는 의사결정자들의 수주에 있을 때 기업에 있어 강력한 경쟁무기가 된다. 의사결정자들의 정보에 대한 이러한 필요성을 충족시키기 위해서 데이타는 운영시스템(Operational System)에서 추출되어 데이타웨어하우스에 저장된다. 데이타웨어하우스는 핵심 비지니스영역(key business dimension)에 의해 정리된 historical data를 저장한다. 이러한 의사결정자들을 위한 데이타웨어하우스 정보의 전달은 기존의 클라이언트/서버 시스템 하에서는 많은 지원을 요구한다. 즉 기존 클라이언트/서버 시스템 하에서는 사용자들의 접근을 위해 데이타가 추출되고 조직화되어지고 나면, 반드시 분석 소프트웨어가 각 사용자의 컴퓨터에 설치되어야 하고 외부의 사용자를 위한 새로운 운영자가 고용되어야 한다. 사용자의 다양한 요구 그리고 계속적 사용자의 교체는 사용자 지원에 있어 심각한 기업부담으로 작용한다. 또한 클라이언트/서버 시스템에서는 기업외부의 정보 이용자들에게 정보를 제공하는데 있어 장소적 한계점을 가지고 잇다. 인트라넷과 인터넷은 이러한 클라이언트/서버 시스템 환경의 문제에 대해 해답을 제시한다. 인트라넷은 데이타웨어하우스로의 접근을 간단히 할뿐만 아니라 의사결정자들의 정보의 공유와 상호분석의 새로운 단계를 제공한다. 그리고 인터넷은 기업 외부 어디에서나 기업이 제공하는 정보를 이용하고자 하는 사람들에게 접근의 편의성을 제공한다. 즉 데이타웨어하우스의 목표와 인트라넷, 인터넷의 목표는 데이타로의 손쉬운 접근이라는 점에서 동일하다. 이러한 점에 착안하여 인트라넷과 인터넷하에서 운용되는 데이타웨어하우스 시스템 구축을 위한 방안을 제시하고자 한다.다(학생군:8.16kg 작업자군:12.9kg). 심박수를 이용한 생리학적 연구에서는 평균 심박수가 거의 100 이하를 유지하므로써 피실험자들이 8시간 작업기준으로 보아 무리가 없는 최대허용 하중을 결정하였음을 보였다. 또한 각 운반작업에 대한 최대허용 하중을 예측하는 회귀모형을 제시하였다.아직 정립되어 있지 않은 분산 환경하에서의 관계형 데이타베이스의 데이타관리의 분류체계를 나름대로 정립하였다는데 그 의의가 있다. 또한 이것의 응용은 현재 분산데이타베이스 구축에 있어 나타나는 기술적인 문제점들을 어느정도 보완할 수 있다는 점에서 그 중요성이 있다.ence of a small(IxEpc),hot(Tex> SOK) core which contains two tempegatlue peaks at -15" east and north of MDS. The column density of HCaN is (1-3):n1014cm-2. Column density at distant position from MD5 is larger than that in the (:entral region. We have deduced that this hot-core has a mass of 10sR1 which i:s about an order of magnitude larger those obtained by previous studies.previous studies.업순서들의 상관관계를 고려하여 보다 개선된 해를 구하기 위한 연구가 요구된다. 또한, 준비작업비용을 발생시키는 작업장의 작업순서결정에 대해서도 연구를 행하여, 보완작업비용과 준비비용을 고려한 GMMAL 작업순서문제를 해

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.1
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• pp.17-30
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• 2018

Currently, the global climate change response paradigm has been changed to a universal response system in which all nations, not the developed countries, participate. Korea has also set a target of 25.9 million tons of transportation greenhouse gas reduction targets by 2030. Korean society is expected to enter the super aging society in 2026. In this study, to reduce the greenhouse gas emissions in public transport and to improve the convenience of transportation vulnerable, we estimate the willingness to pay(WTP) and social benefits assuming that the existing feeder buses are replaced with medium-sized low floor electric buses. To this end, survey was conducted on bus users in the metropolitan area and WTP was estimated by using contingent valuation method(CVM), which is one of the non-market value evaluation methods. As a result of estimation of WTP, the average WTP is 51.4 (won / time person), estimated the economic benefits were 50 million won on weekdays and 40 million won on weekends in Gyeonggi Province in 2014.

• Journal of Radiation Protection and Research
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• v.9 no.2
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• pp.90-96
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• 1984

Estimated dose rates in spent fuel pool storage with the extended fuel cycle core management were reviewed and compared with design limit after calculation with the aid of DLC-23/CASK(22 n, 18 g) nuclear data and ANISN code. Radioactivity and gamma spectrum within spent fuel assemblies were calculated with ORIGEN code by extended fuel cycle model. In the calculation of dose rate, the fuel pool geometry was assumed to be infinite slab. Also, composition materials and radiation source within assemblies which are being stored in pool storage were assumed to be uniformly distributed throughout all the assemblies. As a result of culculation of dose rate from stored assemblies and waterborne radionuclides in pool water, the calculated dose rates appear to be lower than design basis limit under normal condition as well as abnormal condition.

• Environmental and Resource Economics Review
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• v.29 no.2
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• pp.219-246
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• 2020

From the Phase II (2018~2020) of K-ETS, the offset credit from 'CDM projects that domestic companies and others have carried out in foreign countries' can be used in the K-ETS. As a result, stakeholders in the K-ETS market are actively developing overseas CDM projects, such as the 'high-efficiency cook stove project'. which can secure a large amount of credits while marginal cost is relatively low. This paper develops the investment decision-making model of offset project for the 'high-efficiency cook stove project' using the real option approach. Under the uncertainty of the emission allowance price, the optimal investment threshold (p^⁎) is derived and sensitivity analysis is conducted. As a result, in the standard scenario (PoA-S), the optimal investment threshold is 29,054won/ton, which is lower than the stock price (p^⁎_spot). However, allocation entities are not only economics in the CDM project, but also CDM risk factors such as non-renewable biomass ratio, cook stove replacement ratio, equity ratio with host country, investment period and submission limitation of emission allowance. In addition, offset project developers will be able to derive the optimal investment threshold for each business stage and use it for economic feasibility checks.

• Fire Science and Engineering
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• v.33 no.2
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• pp.114-123
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• 2019

The paper relates to a study on the changes in performance of insulation sheath resulting from accelerated degradation of IV and HIV insulated wire. To assume insulation degradation of IV and HIV insulated wire, accelerated life tests using Arrhenius equation were conducted among accelerated life test models, and experimental samples of 0 year, 10 years, 20 years, 30 years, and 40 years in equivalent life were produced. Whereas the maximum tensile load were increased as accelerated degradation of IV and HIV insulated wire progressed, elongation percentage, rupture time, and flexibility of insulated wires were found to be gradually reduced. According to the additional surface analysis results for the insulated wires per equivalent life using a scanning electron microscope, mechanical properties of the insulator were observed to be reduced as insulation degradation resulting from aging progressed since phenomena such as formation of crystalline structures and perforation, etc. occurred on the sample surface with progression of accelerated degradation. Consequently, institutional replacement of insulated wires and preparation of repair times considering performance degradation of the insulator installed inside buildings are considered necessary in order to prevent in advance the risks of electrical fire resulting from degradation in insulation performance.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.227-235
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• 2021

The purpose of this study was to investigate the association factors of dental infection control by applying the health belief model in the dental hygienists. This study subject was 142 dental hygienists from 15 to July 5, 2020. Data were analyzed by chi-square test ANOVA, correlation analysis, and multiple regression analysis using SPSS version 23.0. The performance of dental infection control in accordance with the general characteristics of research subjects was high in case when they had educational experiences of infection control, and when they 'always' did medical examinations by interview about infectious diseases(p<0.01). The group of dental hygienists working for dental clinics with less than average 50 patients a day showed the highest rate of wearing a mask and latex gloves as personal protective gears(p<0.05),(p<0.01). When the wearing of protective goggles(face shield) and the frequency of exchanging masks after the outbreak of COVID-19 were more, the performance for infection control was increasing(p<0.05),(p<0.01),(p<0.001). In this study, it is difficult to generalize the results of the study because the research area and the subject are limited by selecting the subjects by convenience extraction, and focusing on the degree of awareness of infection control by dental hygienists, the actual status of infection control in dentistry is carefully illuminated. What you didn't do can be seen as a limitation. Considering the results of this study, the performance of infection control could be increased by removing obstacles and increasing the importance and perceived benefits of infection control of dental hygienists.

• Journal of Appropriate Technology
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• v.7 no.1
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• pp.51-58
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• 2021

This study proposes the design and implementation of a low-cost emergency ventilator which can be helpful during the COVID-19 pandemic where the supply of automatic ventilators is not smooth compared with the urgent demand worldwide. Easy implementation and lower price were made possible by using AMBU-bag and off-the-shelf embedded micro-controller board. Moreover, while 3D printing is used by companies and experts around the world to build prototype hardware, materials which are readily available from surrounding environments so that people in countries where it is difficult to access many advanced technologies could manufacture the system. The design features AMBU-bag automation, not use 3D printing, and it can contrl speed. By allowing speed control, ventilation can be performed according to the conditions of the patient being used. A complementary point in the study is that it is difficult to fix the start point of the wiper motor used first. A method for complementing this is a method for replacing the brush DC motor with a position feedback function. Secondly, the AMBU-bag may wear out in the long-term process of compressing the AMBU-bag because the arm and the fixing frame are made of wood. To complement this, the part of fixing frame and arm parts that the AMBU-bag touches need to be wrapped in a material such as silicon to minimize friction.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.509-523
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• 2023

The high-level nuclear waste (HLW) repository is exposed to complex environmental conditions consisting of high temperature, high humidity, and radiation, resulting in structural deterioration. Therefore, structural health monitoring is essential, and piezo sensors are used to detect cracks and estimate strength. However, since the monitoring sensors installed in the disposal tunnel and disposal container cannot be replaced or removed, the quantitative life of the monitoring sensor and its suitability must be assessed. In this study, the life of a piezo sensor for monitoring was assessed using an accelerated life test (ALT). The failure mode and mechanism of the piezo sensor under high temperature conditions were determined, and temperature stress's influence on the piezo sensor's life was analyzed. ALT was conducted on temperature stress and the relationship between temperature stress and piezo sensor life was suggested. The life of the piezo sensor was assessed using the Weibull probability distribution and the Arrhenius acceleration model. The suggested relationship can be used in multiple stress ALT designs for more precise life assessment.