• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.665-672
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• 2002

인터넷 공동구매가 실무적으로 많은 관심과 주목을 받고 있음에도 불구하고 공동구매에 대한 학술직인 논의는 그리 많이 이루어지지 못하고 있으며 특히 인터넷 공동구매를 소비자 행동론적 관점에서 실증적으로 분석한 연구는 찾아보기 힘들다. 본 논문에서그 인터넷 소비자들이 공동구매사이트를 통한 인터넷 공동구매에 대해 기지고 있는 태도와 의도에 영향을 주는 요소를 인터넷 개별구매와의 장단점 비교에 의해 분석하였다. 이론적인 검토를 통해 인터넷 공동구매가 인터넷 개별구매에 대해 가질 수 있는 상대적 장점으로 가격절감, 위험감소, 거래비용 절감을 설정하였고, 제품다양성의 부족 및 시간지연을 상대적 단점으로 하였다. 제안된 연구모형의 타당성을 입증하기 위해 각 변수에 대한 측정척도를 미련하여 설문지를 작성배부하였고, 이 가운데 타당하다고 인정되는 355부의 설문지를 분석하였다. 결과적으로 구조방정식에 대한 만족할만한 모형 적합도를 구했고, 위험감소와 인터넷 공동구매 태도와 관련된 가설을 제외한 모든 가설이 채택되었다. 본 연구는 인터넷 공동구매를 소비자 지각의 입장에서 새로운 연구모형을 제시하였고 이에 대한 실증적 검증을 통해 타당성을 입증하였다는 점에서 이론적으로는 물론이고 실무적으로도 큰 의의를 지니고 있다.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.597-602
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• 2007

데이터 마이닝 분야에서 앙상블 모형의 유용성은 널리 인정되고 있다. 앙상블을 구성하는 단위모형들 사이의 다양성이 보장되는 경우, 최종 모형의 정확성 및 안정성이 향상되기 때문이다. 하지만, 얼마나 많은 단위 모형들이 어떤 방식으로 결합되어야 하는가에 대해서는 아직도 더 많은 연구가 필요하다. 본 연구에서는 신용카드 부정사용 유형 중 하나인 현금불법융통 문제에 대해 앙상블 모형의 유용성을 검증하고자 한다. 부정행위 적발 모형은 전형적인 분류 문제의 한 유형이나, 클래스간 불균형이 매우 심하다는 특징이 있다. 따라서, 현금불법융통 문제에 적합한 다양성(Diversity) 척도를 개발하여 최소한의 단위모형들로 앙상블 모형을 구성하는 방안을 제시하였다. 축소된 앙상블 모형이 많은 수의 모형을 결합한 앙상블 모형과 거의 같은 정확성 및 안정성을 보임을 국내 신용카드사의 실제 자료를 사용하여 입증하였다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.6
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• pp.508-516
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• 2017

The M&S (Model and Simulation) has been increasingly used in the wide area of applications and the official certification or accreditation of the M&S are becoming a mandatory requirement to prevent the risks and mishaps caused by the usage of inadequate M&Ss or by misuses of the M&S. This paper threats the VV&A (Verification, Validation, and Accreditation) for the M&S used in the development of the aerospace systems, where most M&S used in the development are derived from the physical laws and the final validation data are typically obtained through a series of flight tests after the prototype production. Considering these unique features, the paper proposes the M&S life-cycle model and development paradigm suitable for the aerospace-system development and accesses the proposed ones by comparative investigation on the relevant regulations and related literatures.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.2
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• pp.223-230
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• 2013

Recently, a large number of corporations are adopting cloud solution in order to reduce IT-related costs. By the way, Digital Trace should have admissibility to be accepted as digital evidence in court, and integrity is one of the factors for admissibility. In this context, this research implemented integrity verification test to VM Data which was collected by well-known private cloud solutions such as Citrix, VMware, and MS Hyper-V. This paper suggests the effective way to verify integrity of VM data collected in private cloud computing environment based on the experiment and introduces the error that EnCase fails to mount VHD (Virtual Hard Disk) files properly.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.69-77
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• 2011

This study is to suggest a methodology to overcome the uncertainty and lack of reliability of data. The fuzzy reasoning model and the neural network model were developed in order to overcome the potential lack of reliability which may occur during the process of data collection. According to the result of comparison with the Poisson regression model, the suggested models showed better performance in the accuracy of the accident frequency prediction. It means that the more accurate accident frequency prediction model can be developed by the process of the uncertainty of raw data and the adjustment of errors in data by learning. Among the suggested models, the performance of the neural network model was better than that of the fuzzy reasoning model. The suggested models can evaluate the safety of signalized intersections in operation and/or planning, and ultimately contribute the reduction of accidents.

• Information Systems Review
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• v.5 no.1
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• pp.49-60
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• 2003

The purpose of this study is to empirically and practically verify the applicability of visualization data mining tool in detecting real-word insurance frauds that are now emerged as one of the most serious problems socially and economically. For the verification, Analyst's Notebook by i2, which has been known as the most effective visualization data mining tool, was adopted. With Analyst's Notebook, fraud-probable insurance transactions from a very large insurance claims are selected and then substantiation for insurance frauds are attempted. The results show that Analyst's Notebook not only detects insurance fraud transactions from a vast number of insurance claims, but is also able to pinpoint organized crime group by associating one fraud transaction to another fraud transaction. Therefore, it is safe to conclude that visualization data mining is very effective in detecting false transactions and crime behaviors including insurance fraud.

• The Journal of the Korea Contents Association
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• v.13 no.5
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• pp.354-365
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• 2013

The purpose of the study was to develop the home fall prevention checklist for community-dwelling older adults. And the validity and reliability of the checklist were tested. The preliminary questions were developed through content validity by twenty experts using the CVI(Content Validity Index). Following the establishment of content validity, 52 items of the checklist were developed. Responses of 299 community-dwelling older adults were analyzed to further establish both reliability and validity of the checklist. Reliability using cohen's kappa coefficient and test-retest reliability(rate of concordance(%)), and construct validity using known-group comparison technique were tested. 51 items were over 0.80 in the cohen's kappa coefficient of the checklist, 45 items were over 80.0% in test-retest reliability. Construct validity was established by known-group comparison(t=3.50, p=.001). Validity and reliability of the checklist were confirmed. This checklist will help further studies to develop more safe environment to prevent falls.

• Korean Journal of Poultry Science
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• v.31 no.3
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• pp.145-150
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• 2004

Two experiments were conducted to evaluate the nutritional values of rice bran and to examine effects of its dietary supplementation on broiler performances. In the first experiment, true metabolizable energy(TME), nitrogen corrected true metabolizable energy(TMEn), and true amino acid availability(TAAA) values of the rice bran were determined by force-feeding sixteen roosters(ISA-Brown). In the second experiment, 3-week-old male broiler chickens(Avian) were divided into four groups and fed each one of four experimental diets containing 0, 5, 10 or 15% rice bran for 21 days. TME and TMEn values of the rice bran(dry matter basis) were 3.25 kcal/g and 3.12 kcal/g, respectively, and the average TAAA value of the 16 amino acids was 76.21%. The average feed intake and body weight gain of the birds fed diets containing rice bran were apparently greater than those of the control group although the differences were not significant statistically. From the results, it can be concluded that feed formulation using bioavailability values, such as TMEn and TAAA, is an effective method for protecting the high variation in growth performances and that rice bran can be used for broiler feeds to 15% without any significant negative effects.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.83-99
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• 2008

Images of Seong-Nam appears different according to diverse conditions. This study was intended to analyze the differences of cognition by personal characteristics such as age, gender, location, and period when an individual evaluates an urban image. This research focused on the interpretation of the visualized results from Multidimensional Scaling (MDS) and Individual Difference Scaling (INDSCAL) with two questionnaires. This study can be summarized as follows: 1. Namhan Sansung was ranked as the first symbolic property by citizens in Seong-Nam. Next was Yuldong Park, followed by Bundang Central Park, Seohyun Station including Samsung Plaza, and, finally, Moran Market. This trend also similarly appeared in the selection of preferred places. 2. There were no statistical differences in trends of choice of symbolic landmarks and preferred places according to age, gender, and period; however, there were meaningful differences according to location. 3. The total image of Seong-Nam was positioned to be separated from images of other districts and landmarks on the image spatial plot by MDS; however, images of the old and new district were plotted close to symbolic landmarks where located around each district. 4. INDSCAL illustrated that men weighted the historical meaning while women weighted preference and city size when evaluating an urban image. On the other hand, there was no difference in cognitive trends according to age, location, and period. Until now, an individual difference in the cognition and evaluation of an urban image was a socially accepted notion. However, this study verified the difference according to personal characteristics and developed a practical tool to analyze an individual cognition trend about a city image.

• Economic and Environmental Geology
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• v.45 no.2
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• pp.169-180
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• 2012

The ESBs (Environmental Specimen Banks) have monitoring functions for the contemporary environmental qualities and also offer the future generation tangible information on the past environment by preserving the specimens. This entails the sampling of the representative specimen for each distinctive ecosystem, which is performed under a strict and stipulated procedure and a condition that does not allow any change in the component so that a retrospective analysis can be readily done even in the distant future. It has been more than 30 years that some developing countries started collecting a broad spectrum of specimens to vindicate the effectiveness of an environmental policy and to monitor the long-term variations of background concentrations of environmental pollutants. Though being late, the National Institute of Environmental Research (NIER), Korea, has successfully launched the National Environmental Specimen Bank (NESB) in 2009 equipped with its state-of-the-art automated cryogenic tanks. Since then, the researchers at the NESB have been doing their best to excel the existing ESBs around the world by learning and improving the expertise. To do so, they conducted a pilot study for developing and testing their own Standard Operating Procedure (SOP) based on the analysis of the examples of the other ESBs. The problems from the pilot study had been reviewed to improve the SOP to meet the requirements for an ESB, that is to say, preserving representative environmental specimens in cryogenic condition and enhancing the analytical method. Furthermore, they also need to prepare themselves to address the future challenges by providing some additional functions, which makes it distinguishable from the other ESBs. If successful, this will be a step further to be recognized as a full-fledged member of the ESB society of the world.