• Review of Culture and Economy
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• v.20 no.2
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• pp.149-171
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• 2017

This paper presents empirical findings about the market inefficiency field in the korean horse track. We first use the place betting data instead of the win betting data inevitably depended on by past studies, and discuss the degree of the long shot anomaly and the bettor's risk attitude sequentially in the place betting market. The empirical result of betting simulations using the place winning function in this study reveals persistently higher returns than the expected payoff in korean racetrack betting market. The clear departures from perfect efficiency in horse-racing betting imply that much of the market information is insufficient and less accurate. This market asymmetry aggravates popular speculations exquisitely since people are attracted by the higher odds figures in the racetrack display although those are much uncertain in future. The findings suggest the more objective and credible information of winning possibilities such as the place winning function including the smart information of marginal odds needs to be available to the betting decision of the public, which contributes to reducing the speculative spirit in korean racetrack.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.4
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• pp.304-309
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• 2015

To evaluate the degree of contamination caused by oil spill accident in the sea, the in-situ sensors which are based on the scientific method are needed in the real site. The sensors which are based on the fluorescence detection theory can provide the useful data, such as the concentration of oil. However these kinds of sensors commonly are composed of the ultraviolet (UV) light source such as UV mercury lamp, the multiple excitation/emission filters and the optical sensor which is mainly photomultiplier tube (PMT) type. Therefore, the size of the total sensing platform is large not suitable to be handled in the oil spill field and also the total price of it is extremely expensive. To overcome these drawbacks, we designed the fluorimeter for the oil spill detection which has compact size and cost effectiveness. Before the detail design process, we conducted the experiments to measure the excitation and emission spectrum of oils using five different kinds of crude oils and three different kinds of processed oils. And the fluorescence spectrometer were used to analyze the excitation and emission spectrum of oil samples. We have compared the spectrum results and drawn the each common spectrum regions of excitation and emission. In the experiments, we can see that the average gap between maximum excitation and emission peak wavelengths is near 50 nm for the every case. In the experiment which were fixed by the excitation wavelength of 365 nm and 405 nm, we can find out that the intensity of emission was weaker than that of 280 nm and 325 nm. So, if the light sources having the wavelength of 365 nm or 405 nm are used in the design process of fluorimeter, the optical sensor needs to have the sensitivity which can cover the weak light intensity. Through the results which were derived by the experiment, we can define the important factors which can be useful to select the effective wavelengths of light source, photo detector and filters.

• Journal of Intelligence and Information Systems
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• v.20 no.3
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• pp.93-108
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• 2014

To support business decision making, interests and efforts to analyze and use transaction data in different perspectives are increasing. Such efforts are not only limited to customer management or marketing, but also used for monitoring and detecting fraud transactions. Fraud transactions are evolving into various patterns by taking advantage of information technology. To reflect the evolution of fraud transactions, there are many efforts on fraud detection methods and advanced application systems in order to improve the accuracy and ease of fraud detection. As a case of fraud detection, this study aims to provide effective fraud detection methods for auction exception agricultural products in the largest Korean agricultural wholesale market. Auction exception products policy exists to complement auction-based trades in agricultural wholesale market. That is, most trades on agricultural products are performed by auction; however, specific products are assigned as auction exception products when total volumes of products are relatively small, the number of wholesalers is small, or there are difficulties for wholesalers to purchase the products. However, auction exception products policy makes several problems on fairness and transparency of transaction, which requires help of fraud detection. In this study, to generate fraud detection rules, real huge agricultural products trade transaction data from 2008 to 2010 in the market are analyzed, which increase more than 1 million transactions and 1 billion US dollar in transaction volume. Agricultural transaction data has unique characteristics such as frequent changes in supply volumes and turbulent time-dependent changes in price. Since this was the first trial to identify fraud transactions in this domain, there was no training data set for supervised learning. So, fraud detection rules are generated using outlier detection approach. We assume that outlier transactions have more possibility of fraud transactions than normal transactions. The outlier transactions are identified to compare daily average unit price, weekly average unit price, and quarterly average unit price of product items. Also quarterly averages unit price of product items of the specific wholesalers are used to identify outlier transactions. The reliability of generated fraud detection rules are confirmed by domain experts. To determine whether a transaction is fraudulent or not, normal distribution and normalized Z-value concept are applied. That is, a unit price of a transaction is transformed to Z-value to calculate the occurrence probability when we approximate the distribution of unit prices to normal distribution. The modified Z-value of the unit price in the transaction is used rather than using the original Z-value of it. The reason is that in the case of auction exception agricultural products, Z-values are influenced by outlier fraud transactions themselves because the number of wholesalers is small. The modified Z-values are called Self-Eliminated Z-scores because they are calculated excluding the unit price of the specific transaction which is subject to check whether it is fraud transaction or not. To show the usefulness of the proposed approach, a prototype of fraud transaction detection system is developed using Delphi. The system consists of five main menus and related submenus. First functionalities of the system is to import transaction databases. Next important functions are to set up fraud detection parameters. By changing fraud detection parameters, system users can control the number of potential fraud transactions. Execution functions provide fraud detection results which are found based on fraud detection parameters. The potential fraud transactions can be viewed on screen or exported as files. The study is an initial trial to identify fraud transactions in Auction Exception Agricultural Products. There are still many remained research topics of the issue. First, the scope of analysis data was limited due to the availability of data. It is necessary to include more data on transactions, wholesalers, and producers to detect fraud transactions more accurately. Next, we need to extend the scope of fraud transaction detection to fishery products. Also there are many possibilities to apply different data mining techniques for fraud detection. For example, time series approach is a potential technique to apply the problem. Even though outlier transactions are detected based on unit prices of transactions, however it is possible to derive fraud detection rules based on transaction volumes.

• Korea journal of population studies
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• v.9 no.1
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• pp.89-99
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• 1986

이 연구는 우리나라에 있어서의 도시로의 인구이동과 도시매력도와의 관계를 <인지-행태>론적인 관점에서 설명하려데 그 목적이 있다. Julian Wolpert (1965)의 "장소효용접근방법"으로 체계화된 이 이론의 요지는 사람들이 이주대상지를 결정함에 있어서 그 대상지의 객과적인 매력도 보다는 자신들이 갖고 있는 정보를 토대로 주관적으로 판단한 이른바 "인지된 매력도"에 좌우된다는 점이다. 이 연구에서는 우리나라의 자료를 토대로 Wolpert의 가설을 검증하여 보았다. 인구이동의 관점에서 본 도시매력도의 구성요소를 (1) 소득수준, (2) 취업기회, (3) 교육기회, (4) 주거사정, (5) 도시시설의 질, (6) 이주시 도움을 받을 수 있는 친지의 유무, (7) 사회적 성장기회 등 7개 항목으로 분류하여 우리나라의 도시들을 객관적인 매력도와 주관적인 매력도로 계량화하였다. 객관적인 매력도는 기존의 통계자료를 지표화하여 측정하였고, 주관적인 매력도는 충청북도 주민들을 대상으로 1983년 현재 인구 10만 이상의 36개 도시에 대한 매력도 순위 설문조사를 통해 계량화하였다. 이들 매력도를 독립변수로 하고 충북으로부터 각 도시로 전출된 인구를 종속변수로 하여 통계적 분석을 한 결과 객관적인 매력도는 인구이동 현상을 55-58% 설명하였으나, 주관적인 매력도는 약 95%정도 설명하는 것으로 나타나 인구이동 의사결정이 주민들에게 인지된 주관적 매력도에 크게 의존하고 있음이 판명되었다. 따라서 학교교육이나 대중매체를 이용한 장기적인 <인포메이션 프로그램>을 개발하여 농촌생활이나 중소도시에서의 생활의 장점을 널리 계몽하여 도시의 주관적 매력도와 객관적 매력도간의 간격을 좁혀주는 정책도 매우 유용한 대도시 인구분석정책대안의 하나가 될수 있을 것이다.정책대안의 하나가 될수 있을 것이다.다. 고로 본고에서는 주사제의 처방설계및 제조(방법, 공정)에 관하여 개괄적으로 논하고자 한다.약화되어 저적면적빈도분포가 정상분포 단계에 도달되기 전에 바로 platykurtic분포로 되는 것이 아니고 leptokurtic 분포적 단계를 거친다고 본다때 시간의 경과를 따라 생성되어지는 Cyclodextrin의 함량의 변화를 추적하여 4시간전후에서 최고량이 되는 것을 볼 수 있으며 동시에 포위화합물을 형성시킬수 있을때는 그 생성률이 큰 영향을 이르킬수 있는 것을 지적할 수 있다.한 특성을 보여 식품제조, 식육연화 등 식품산업 분야에서의 활용가능성이 높을 것으로 보이며, 나아가 단백질이 갖는 식품학적 기능성을 높이는 데에도 사용할 수 있을 것으로 판단된다.를 한 후 저온 냉장차를 이용하여 유통한다면 관행 유통 구조보다 고품질의 포도를 유통시킬 수 있는 것으로 사료되며 앞으로는 완숙된 고 당도(12.0~15.0Bx)$^{\circ}$ 포도를 수확 한 즉시 예냉 처리하고 저온 유통한다면 보다 신선한 과일을 소비자에게 전달 할 수 있을 것이다.갈변물질이 생성되었다. 이와 같은 결과로 볼 때, BAAG의 처리는 BAAC의 경우보다 가격은 저렴하면서도 항균력은 우수한 천연 항균복합제재로써 농산물 식품원료에 적용하여 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다. 과일 등의 포장제로서 이용할 가능성을 확인하였다.로 [-wh] 겹의문사는 복수 의미를 지닐 수 없 다. 그러면 단수 의미는 어떻게 생성되는가\ulcorner 본 논문에서는 표면적 형태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elements)로 가정한다. 즉, [+wh] 의미의 겹의문사는

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1750-1758
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• 2015

The purposes of this study were to investigate the effects of university foodservice quality attributes on Chinese students' satisfaction, as well as the mediating effects of perceived value on the relationship between foodservice quality attributes and satisfaction. A total of 250 university students in Daejeon were surveyed, and 216 responses were returned. Excluding responses with significant missing data, 196 responses were used for data analysis. The reasons for using university foodservice were 'meal plan' (37.8%) and 'time saving' (22.4%), whereas the reasons for not using university foodservice were 'untasty food' (33.2%) and 'limited menu selection' (27.6%). Results confirm that enhanced performance of food quality, service quality, sanitation, and convenience had favorable effects on perceived value and satisfaction. Further, perceived value had a significant positive influence on satisfaction. In analyzing the mediating role, the effect of foodservice quality attributes on satisfaction was partially mediated by perceived value.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.93-102
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• 2016

Vehicle-to-Grid (V2G) system, bi-direction power trading technology, enables drivers possessing electric vehicle to sell the spare electricity charged in the vehicle to power distribution company. The drivers gain profit by charging electricity in the day time of high electricity rate. In this regard, the government is preparing the policies of building and supporting V2G infrastructure and demanding the potential consumers' preference for the V2G system. This paper attempts to analyze the consumers' preference using the data from obtained a survey of randomly selected 1,000 individuals. To this end, choice experiment, an economic technique, is employed here. The attributes considered in the study are residual amount of electricity, electricity trading hours, required plug-in time, and price measured as an amount additional to current gasoline vehicle price. The multinomial logit model, which requires the assumption of 'independence of irrelevant alternatives', is applied but the assumption could not be satisfied in our data. Thus, we finally utilized nested logit model which does not require the assumption. All the parameter estimates in the utility function are statistically significant at the 10% level. The estimation results show that the marginal willingness to pay (MWTP) for one hour increase in electricity trading hours is estimated to be KRW 1,601,057. On the other hand, a one percent reduction in residual amount of electricity and one hour reduction in required plug-in time in V2G system are computed to be KRW -91,911 and -470,619, respectively. The findings can provide policy makers with useful information for decision-making about introducing and managing V2G system.

• Journal of Korean Society of Forest Science
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• v.71 no.1
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• pp.14-21
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• 1985

This study was carried out in order to prevent the devaluation of wood itself and wood products causing by anisotropy, hygroscopicity, shrinkage and swelling - properties that wood itself only have, in order to improve utility of wood, by emphasizing the natural beautiful figures of wood, to develop the dimensional stabilization techniques of wood with PEG that it is a cheap, non-toxic and the impregnation treatment is not difficult, on the effects of PEG molecular weights (200, 400, 600, 1000, 1500, 2000, 4000, 6000) and species (Pinus densiflora S. et Z., Larix leptolepis Gordon., Cryptomeria japonica D. Don., Cornus controversa Hemsl., Quercus variabilis Blume., Prunus sargentii Rehder.). The results were as follows; 1) PEG loading showed the maximum value (137.22%, Pinus densiflora, in PEG 400), the others showed that relatively slow decrease. The lower specific gravity, the more polymer loading. 2) Bulking coefficient didn't particularly show the correlation with specific gravity, for the most part, indicated the maximum values in PEG 600, except that the bulking coefficient of Quercus variabilis distributed between the range of 12-18% in PEG 400-2000. In general, the bulking coefficient of hardwood was higher than that of softwood. 3) Although there was more or less an exception according to species, volumetric swelling reduction was the greatest in PEG 400. That is, its value of Cryptomeria japonica was the greatest value with 95.0%, the others indicated more than 80% except for Prunus sargentii, while volumetric swelling reduction was decreased less than 70% as the molecular weight increase more than 1000. 4) The relative effectiveness of hardwood with high specific gravity was outstandingly higher than softwood. In general, the relative effectiveness of low molecular weight PEG was superior to those of high molecular weight PEG except that Quercus variabilis showed more than 1.6 to the total molecular weight range, while it was no significant difference as the molecular weight increase more than 4000. 5) According to the analysis of the results mentioned above, the dimensional stabilization of hardwood was more effective than softwood. Although volumetric swelling reduction was the greatest at a molecular weight of 400. In the view of polymer loading, bulking coefficiency reduction of swelling and relative effectiveness, it is desirable to use the mixture of PEG of molecular weight in the range of 200-1500. To practical use, it is recommended to study about the effects on the mixed ratio on the bulking coefficient, reduction of swelling and relative effectiveness.