• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.5
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• pp.149-161
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• 2022

Because the speed limit affects moving speed, it is closely related to traffic accidents as well as traffic flow. The existing speed limit calculation methods consider various engineering factors such as lanes, intersection spacing, driveways, crosswalks, 85 percentile speed, land uses, and roadway geometric characteristics etc. However, it can be said that the engineering analysis is insufficient because the traffic impact analysis considering traffic volume is not carried out. In addition, only 85 percentile speed, which is the spot speed, does not reflect the characteristics of the traffic flow on the road. In this paper, the effect of the speed limit change on the moving speed and the travel speed was analyzed in detail accordinr to the variation of intersection spacing and traffic volume. And by using the results, we proposed a speed limit calculation method that maintains the same service level as before the speed limit change, thereby increasing the speed improvement effect and reducing the difference between moving speed and travel speed. In addition, a variable speed limit operation method according to the change in traffic volume was also suggested. This method is expected to be effective in terms of safety by reducing the speed difference, which affects the severity of traffic accidents, while securing the speed improvement effect, and increasing the speed limit compliance rate of drivers by operating the speed limit that reflects the speed change due to the variation of traffic volume.

• KDI Journal of Economic Policy
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• v.33 no.1
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• pp.125-148
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• 2011

Although the patient's problem with access to health information has been improved due to rapidly developing information technologies, such as the internet, some patients still do not have enough ability to understand, interpret, and analyze the health information. Given this view on the patient's asymmetric information problem, if a doctor provides sufficient effort to help patients understand and interpret medical information, the efficiency of patient's medical care use could be improved. This paper shows firstly that the patient's inefficient use of medical care originates from his information problems, such as the misperception of the effectiveness of medical care and secondly suggests that if the doctor makes sufficient effort to correct patient's information problems, the inefficiency can be ameliorated. This paper also suggests the manipulation of a doctor's payment method can lead a doctor to provide optimal level of efforts which can in turn lead patients to use the optimal level of medical care. With an optimal level of effort, a doctor can more easily achieve a patient's compliance with the newly recommended amount of medical care.

• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.195-204
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• 2004

Poisson's ratio due to multiaxial creep of concrete reported by existing experimental works was controversial. Poisson's ratio calculated from measured strain is very sensitive to small experimental error. This sensitivity make it difficult to find out whether the Poisson's ratio varies with time or remain constant, and whether the Poisson's ratio has different value with stress states or not. A new approach method is needed to resolve the discrepancy and obtain reliable results. This paper presents analytical study on multiaxial creep test results. Microplane model as a new approach method is applied to optimally fitting the test data extracted from experimental studies on multiaxial creep of concrete. Double-power law is used as a model to present volumetric and deviatoric creep evolutions on a microplane. Six parameters representing the volumetric and deviatoric compliance functions are determined from regression analysis and the optimum fits accurately describe the test data. Poisson's ratio is calculated from the optimum fits and its value varies with time. Regression analysis is also performed assuming that Poisson's ratio remains constant with time. Four parameters are determined for this condition, and the error between the optimum fits and the test data is slightly larger than that for six parameter regression results. The constant Poisson's ratio with time is obtained from four parameter analysis results and the constant value can be used in practice without serious error.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.9
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• pp.809-815
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• 2017

STS 304 steel is used as pressure vessel material, and although it exhibits excellent mechanical characteristics at a low temperature, it is heavier than other materials. To address this issue, a method using cold-stretching techniques for STS 304 can be applied. In this study, a cold-stretching part and welded joint specimen were directly obtained from a cold-stretching pressure vessel manufactured according to ASME code. Fatigue crack propagation tests were carried out at room temperature and $-170^{\circ}C$ using the compliance method for stress ratios of 0.1 and 0.5. The results indicate that crack growth rate of the welded joint is higher than that of the cold-stretching part within the same stress intensity factor range. The outcome of this work is expected to serve as a basis for the development of a cold-stretched STS 304 pressure vessel.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.3
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• pp.337-352
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• 2015

This study selected a case study method conforming to qualitative research in order to analyzed how each type of fashion enterprises uses SNS in-side of fashion marketing based on content the researcher monitored and selected from the Facebook website for each enterprise. The standard to select fashion brands in this study is a graded list made based on ranking 5 analysis sites on social media (Socialbakers, socialDigm, Pulse K, BigFoot9, L2). The researcher sorted and then analyzed 2 brands that have many fan joiners and followers among fashion brands that were ranked top of the graded list, work in Facebook animatedly, and had representativeness in each type (SPA, Sports Brands). The study was conducted from January 2013 to March 2013, and the index of Facebook consisted of 3 kinds of elements (comment, like, and share). Each numerical value was counted to decide the monthly ranking. Content analysis was divided into public relations about brand, public relations about products, and customer participation and activities; consequently, the researcher investigated which content was post conforming to the ranking. The study analyzed the analysis results of each brand derived through the method of study compared to other brands. The results are as follows. In case of SPA brands, the category accounting for high rank in index analysis are public relation events to attract customer attention and products and offering information. The results of the monthly trend about whole post category were also similarly analyzed so the promotion goal that the brand wants to seek in priority coincides with the customer compliance rate. Next, in the case of sports brand, public relations for products offering information, event for arousing customer concern, and participation activities accounted for a high rank in the index analysis and posted the most in the analysis of the monthly trend for whole post category. The researcher came to understand that the direction of content for brands shown through Facebook coincides with customer sympathy.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.4
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• pp.355-361
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• 2011

Sedative method and its effect are affected by diverse variables: dosage and intake method of drug, weight, gender, patient compliance, sleeping hours prior to procedure, treatment hours, health status, type of used drugs are the factors. This study is conducted with empirical observation that shorter the sleeping hours before the day of chloral hydrate sedation, the effectiveness is larger; and therefore to actually recognize the correlation between chloral hydrate/hydroxyzine sedation and sleeping hours of child patient prior to sedation. The subjects were those children whose sleeping hours were similar to each other at the ages ranging from 2 to 5 years old totaling 37 children. Total 11 of them received pulp treatment. Sedative effect was evaluated by the same assessor with Houpt's rating scale. Sedative effect in relation with prior day's sleeping hours evaluated with simple regression analysis. Sedative effect in relation with pulp treatment was analyzed with independent t-test. Sleeping hours prior to sedation and sedation effect have negative correlation. No significant correlation is found between pulp treatment and sedation effect(p>0.05).

• Resources Recycling
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• v.25 no.6
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• pp.13-22
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• 2016

This study is aimed at compare and evaluate the environmental impact of End-of-Life Vehicle(ELV) on the eco-friendly technology dismantling and recycling system, using Life Cycle Assessment (LCA) method. In this study, it was analyzed for the environmental impacts of raw materials, disassemble process, recycle parts separation and waste treatment into the process of ELV treatment by greenhouse gas and resource consumption, etc. Through this study, the indoor rail type dismantling technology were recycling rate applied on the alternate system was increased by approximately 8%. As a result, it was 3 to 88% by improving the environmental impact category. In addition, the added benefit of approximately 8 - 62% in pre-market occurred through the recycling rate, improve parts reuse rate of ELV. Through the results of this study, legal compliance, improved reuse and recycling ratio, used parts market reach, enable exports has identified the need for the effort that the dissemination and diffusion of eco-friendly technology.

• The Journal of Bigdata
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• v.3 no.2
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• pp.19-33
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• 2018

Owing to the increase of FTA, food trade, and versatile preferences of consumers, food import has increased at tremendous rate every year. While the inspection check of imported food accounts for about 20% of the total food import, the budget and manpower necessary for the government's import inspection control is reaching its limit. The sudden import food accidents can cause enormous social and economic losses. Therefore, predictive system to forecast the compliance of food import with its preemptive measures will greatly improve the efficiency and effectiveness of import safety control management. There has already been a huge data accumulated from the past. The processed foods account for 75% of the total food import in the import food sector. The analysis of big data and the application of analytical techniques are also used to extract meaningful information from a large amount of data. Unfortunately, not many studies have been done regarding analyzing the import food and its implication with understanding the big data of food import. In this context, this study applied a variety of classification algorithms in the field of machine learning and suggested a data preprocessing method through the generation of new derivative variables to improve the accuracy of the model. In addition, the present study compared the performance of the predictive classification algorithms with the general base classifier. The Gaussian Naïve Bayes prediction model among various base classifiers showed the best performance to detect and predict the nonconformity of imported food. In the future, it is expected that the application of the abnormality detection model using the Gaussian Naïve Bayes. The predictive model will reduce the burdens of the inspection of import food and increase the non-conformity rate, which will have a great effect on the efficiency of the food import safety control and the speed of import customs clearance.

• Food Science and Industry
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• v.55 no.1
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• pp.58-73
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• 2022

Due to the recent demand for low-calorie foods, consumers are looking for alternative sweeteners that can control blood sugar, low risk of tooth decay and low calories. Regulations for permitted sweeteners in food vary from every country, and it is important for the government and the food industry to monitor products containing these sweeteners to ensure global compliance. Therefore, rapid, precise, and accurate analysis for food matrices should be applied to quality control, market surveillance, monitoring, and evaluation of food additive intake in the food industry. To analyze sweeteners simultaneously, it is essential to develop an efficient and rapid analytical method and to perform appropriate pretreatment steps such as solvent extraction and purification. This study presented the recent analysis trends about the suitable extraction method for food matrices focusing on non-nutritive sweeteners. Additionally, techniques for multi-compounds analysis using HPLC and LC-MS/MS and non-destructive analysis techniques using FT-IR were comprehensively described.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.284-298
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• 2022

It is necessary to acquire information on traffic safety facilities installed on the roadways specifically for the operation of autonomous vehicles. The purpose of this study is to prepare a Korean version of an integrated message-set design as a way to provide to autonomous vehicles standardized information on traffic safety facilities. In this study, necessary facilities are classified according to four criteria (no legal basis; not providing information to autonomous vehicles; providing duplicate information; not standardized, and too difficult to generalize) based on information that must be provided to operate autonomous vehicles. The priority of information delivery (gross negligence followed by behavior change) was classified according to the importance of the information to be provided during autonomous driving, and the form was defined for the classification code in the information delivered. Finally, the information location and delivery method of traffic facilities for compliance with SAE J2735 were identified. This study is meaningful in that it provides a plan for roadway operations by suggesting a method for providing information to autonomously driven vehicles.