• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.7
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• pp.757-764
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• 2014

In this study, the effect of shape parameters on the J-R curves of curved CT specimens was evaluated using the limit load method. Fracture toughness tests considering the shape factors L/W and $R_m/t$ of the specimens were also performed. Thereafter, the J-R curves of the curved CT specimens were compared using the J-integral equation proposed in the ASTM (American Society for Testing and Materials) and limit load solution. The J-R curves of the curved CT specimens were also compared with those of the CWP (curved wide plate), which is regarded to be similar to real pipe and standard specimens. Finally, the effectiveness of the J-R curve of each curved CT specimen was evaluated. The results of this study can be used for assessing the applicability of curved CT specimens in the accurate evaluation of the fracture toughness of real pipes.

• Archives of design research
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• v.16 no.2
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• pp.49-56
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• 2003

In order to design a product for old people, it is important to identify usability problems through usability test and solve such problems in design process. So, we performed a study on design evaluation and improvement focusing on washing machine, that is one of the most useful electric home appliances in old people's daily life. Also, we studied the method that the goniometer can be used in usability evaluation for a specific part of product and the result can be used in product design. And, methods for the decision of design concept and direction, the development of design alternatives, design evaluation, model making, and comparison test through human factors theory and experiment were studied. The result can be used as an important data in the development of washing machine for old people and the proposed methodology can be used in other products for old people as well as washing machine.

• Journal of Korean Society of Transportation
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• v.28 no.6
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• pp.55-62
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• 2010

The purpose of this research is to provide an a basic data for setting design standards and proposing improvement for public open space by analysis one which is the factor that quite influences public open space by factor analysis. First, Extract main design factors by survey and field investigation of the Public Open Space of Centum and Seomyeon in Pusan. After the extraction, Control and simulation of main design factors which selected by survey for making better improved public open space and resolving problems of it. Based on simulation data, the five-factors drawed by psychological estimation and factor analysis are Accessibility, Intimacy, Openness, Amenity, Convenience. By use of a result, Multiple Regression Analysis is implemented for correlation analysis between five-factors and user's satisfaction in the public open space. Therefore the it which influenced user's satisfaction in the public open space most was Accessibility. So, the public open space must be designed to improve Accessibility and Intimacy, Openness, Amenity, Convenience which influenced user's satisfaction were reviewed primary.

• Environmental and Resource Economics Review
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• v.28 no.4
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• pp.645-673
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• 2019

The hypothetical nature of stated preferences can lead to a hypothetical bias that might work as a normative pressure, influencing survey responses. This paper aims to test the impact of social desirability bias by comparing economic estimates based on both subjective and objective valuation questions. The case study is about an urban riverine restoration project in Deajeon, South Korea. As valuation methods both contingent valuation and choice experiments were comparatively applied. Based on a nationally representative sample of 1,000 respondents, the test results offered contrasting conclusions between two test approaches. Accroding to the estimation results based on the conventional valuation, the marginal willingness to pay estimates are 10,500 KRW from CV; and 18,600 KRW for improving water quality, 2,200 KRW for the inside view, 8,900 KRW for the outside view, and 5,800 KRW for biodiversity from CE. A segmentation-based approach is a conventionally used method, which showed a limited impact of social desirability on willingness to pay estimates. The alternative parameterization-based approach measures a model-wide impact of social desirability, proving a significant bias. Although the study positioned a cheap-talk statement before the valuation section of the survey questionnaires, which might have pre-screened the bias, the overall implications of the results suggest a caution in reducing and observing hypothetical bias. There might remain a significant and substantial hypothetical bias even after cheap-talk, particularly in situations with strong social desirability, so that the potential role of objective valuation questions is guaranteed.

• Proceedings of the Korean Reliability Society Conference
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• 2002.06a
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• pp.147-155
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• 2002

본 연구에서는 옥외에서 사용하는 소재의 신뢰성 평가(내후성)에 관한 연구를 수행하였는데 국내와 일본의 옥외환경시험장에 시험편을 동시에 폭로하여 기상인자 및 주변환경에 따른 시험편의 특성 변화를 상호 비교ㆍ평가하였고 인공 촉진내후성 시험을 실시하여 옥외내후성과의 상관관계를 관찰하였으며 그 결과는 다음과 같다. 국내 지역의 옥외환경시험장 중에서는 인천 옥외환경시험장에 폭로한 시험편에서 가장 많은 변화를 나타내고 있으며, 일본 지역은 가혹한 기상환경을 나타내는 미야고지마 옥외환경시험장에 폭로한 시험편에서 많은 변화가 나타남을 관찰할 수 있었는데 국내 지역보다는 온도와 습도 등 기상제조건이 더 가혹한 일본 지역의 옥외환경시험장에 폭로한 시험편의 노화가 더 빠르게 진행됨을 관찰하였다.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.35-48
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• 2021

With the advent of the Fourth Industrial Revolution, startups are leading the proliferation of logistics in life services in countries across the world. Logistics in life startups aim to differentiate themselves for traditional logistics companies by offering customized services that penetrate niche logistics market and enhance customer convenience and satisfaction. Through the development of mobile applications(apps) and platform a variety of life-enhancing services are becoming increasingly available to customers, such as on-demand, online-to-offline, convenience, reverse logistics, as well as last-mile delivery. In particular, logistics in life services are expanding into areas that include food delivery, home moving, cargo transport, laundry delivery, car washing, and car repair. In order for the logistics in life startups to succeed, they needs to offer highly usable apps to increase customer satisfaction and loyalty. Due to the nature of mobile phones, different evaluation criteria than those for websits should be used to determine the usability of apps. The purpose of this study is to evaluate the usability of representative Korean logistics in life apps through usability testing, discuss implications and offer improvement recommendations. Finally, the best Korean logistics app is compared with a top ranked app on Google Play for benchmarking purposes.

• Fire Science and Engineering
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• v.32 no.3
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• pp.116-122
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• 2018

In Chemical, Biological, Radiological and Nuclear (CBRN) disaster, integrated and optimized equipment package including stretcher, isolation unit, patient monitoring and treatment equipment is essential to achieve proper treatment and prevent secondary contamination. The purpose of this study was to evaluate the efficiency and ease of use of integrated CBRN disaster equipment package for disaster medical response. This study was a randomized crossover study using a manikin simulation for emergency medical technitian (EMT). All participants used the existing devices and prototype of integrated CBRN disaster equipment package alternately. Efficiency was measured by time from vital sign change to detection or treatment application. Ease was use was measured by questionnaires for each patient monitor, stretcher care and isolation unit. 12 EMTs were enrolled. hypoxia-detection time of integrated equipment group was significantly shorter than existing equipment group (4.9 s (3.8-3.9) vs 3.5 s (2.5-3.9), p < 0.05). There was decreasing tendency of ECG change detection and facial mask oxygen supply but no statistical significance was observed. Overall satisfaction of patient monitoring device in integrated equipment group was significantly higher than existing devices (4(3.5-5) vs 3(3-3), p < 0.05). The use of integrated CBRN disaster equipment package shortened the hypoxia detection time and improved usability of vital sign monitor compared to existing devices.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.1
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• pp.3-11
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• 2011

This paper aims to develop a web based GIS system which is able to evaluate and visualize the overall degree (in terms of pleasantness and aesthetics) of pedestrian friendliness of the environment, as well as pedestrians' convenience through a Walkability Indicators that simplify pedestrian environment elements into a quantitative index in accordance with characteristics of pedestrian space. To make this goal come true, we developed and applied Walkability index which can measure the pedestrian environment through reflecting quantitative Indicators based on GIS supplementing the limit of Literature Review. In addition, in order to develop index we utilized AHP(Analytic Hierarchy Process) and we displayed measurement result on study area through web GIS Services. The proposed pedestrian measurement system is expected to be applicable in the visualization of pedestrian movements and the evaluation of convenience levels of pedestrian environment.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.2
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• pp.227-234
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• 2019

A user-friendly modeling interface is developed for a process-based total system performance assessment framework (APro) specialized for a generic geological disposal system for high-level radioactive waste. The APro modeling interface is constructed using MATLAB, and the operator splitting scheme is used to combine COMSOL for simulation of multiphysics and PHREEQC for the calculation of geochemical reactions. As APro limits the modeling domain to the generic disposal system, the degree of freedom of the model is low. In contrast, the user-friendliness of the model is improved. Thermal, hydraulic, mechanical and chemical processes considered in the disposal system are modularized, and users can select one of multiple modules: "Default process" and multi "Alternative process". APro mainly consists of an input data part and calculation execution part. The input data are prepared in a single EXCEL file with a given format, and the calculation part is coded using MATLAB. The final results of the calculation are created as an independent COMSOL file for further analysis.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.783-793
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• 2003

The effects of various kinds of starch (mungbean, potato, corn and a blend of potato and com starch) on the quality characteristics of muhwakwa-pyun were studied according to the storage duration. The sweetness, pH and total acidity of muhwakwa extract were analyzed, as were the Visco/Amylograph viscosity profile and DSC thermodynamic characteristics of starches. For quality characteristics, color difference, instrumental texture characteristics and sensory characteristics were compared. The sweetness of muhwakwa extract was satisfactory but the total acidity was low for Kwa-pyun manufacture. Therefore, its pH was adjusted to 3.4 by adding 10％ citric acid with an amount of 1％ of total liquid. From the Visco/Amylograph viscosity profile and DSC thermodynamic characteristics of starches, a blend of potato and com starch was found to be easy to cook and form a gel but a little more resistant than the other starches in terms of retrogradatin. Lightness (L) and yellowness (b) of Kwa-pyun increased while its redness (a) decreased by the storage. The color became whiter and the clarity decrease regardless of the kinds of starch, which became obvious after 3 days of storage. The hardness, springiness, adhesiveness and cohesiveness tended to decrease with storage, which was weak in a blend starch. The overall acceptability of Kwa-pyun made with a blend of potato and com starch was evaluated as being the best among the samples tested. Therefore, for traditional kwa-pyun manufacture manufacture mungbean starch might be replaced with a blend of potato and corn starch which is less expensive and easily available in the market nowadays.