• 제목/요약/키워드: bid rate

검색결과 87건 처리시간 0.02초

경매 시스템에서 시계열 분석에 기반한 낙찰 예정가 추천 방법 (Reserve Price Recommendation Methods for Auction Systems Based on Time Series Analysis)

  • 고민정;이용규
    • Journal of Information Technology Applications and Management
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    • 제12권1호
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    • pp.141-155
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    • 2005
  • It is very important that sellers provide reasonable reserve prices for auction items in internet auction systems. Recently, an agent has been proposed to generate reserve prices automatically based on the case similarity of information retrieval theory and the moving average of time series analysis. However, one problem of the previous approaches is that the recent trend of auction prices is not well reflected on the generated reserve prices, because it simply provides the bid price of the most similar item or an average price of some similar items using the past auction data. In this paper. in order to overcome the problem. we propose a method that generates reserve prices based on the moving average. the exponential smoothing, and the least square of time series analysis. Through performance experiments. we show that the successful bid rate of the new method can be increased by preventing sellers from making unreasonable reserve prices compared with the previous methods.

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인터넷 경매 시스템에서의 낙찰 예정가 자동 생성 에이전트 (A Reserve Price Generation Agent for an Internet Auction System)

  • 고민정;김신우;박성은;이용규
    • 정보처리학회논문지D
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    • 제9D권5호
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    • pp.955-962
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    • 2002
  • 최근에 전자상거래가 보편화되면서 전자경매를 통한 거래가 급증하고 있다. 그러나, 기존 전자경매 시스템들은 낙찰 예정가 결정을 판매자에게만 의존하고 있으므로, 물품의 낙찰가가 낮게 결정되거나 유찰되는 경우가 많다. 본 논문에서는 이러한 문제점을 해결하고자, 과거의 경매 기록과 인터넷 전자상거래 사이트의 가격 정보로부터 사례 유사도를 적용하여 적합한 낙찰 예정가를 자동으로 생성하고 이를 판매자에게 추천하는 시스템을 제안한다. 성능실험 결과 추천된 낙찰 예정가를 사용할 경우 지나치게 높은 낙찰 예정가로 인한 유찰을 줄임으로써 경매 성공률이 향상될 뿐만 아니라, 물품에 대한 낮은 평가를 방지할 수 있음을 보인다. 또한, 본 논문에서는 낙찰 예정가 자동 생성에이전트를 이용하여 인터넷 경매 시스템을 설계 및 구현한다.

THREE-STAGED RISK EVALUATION MODEL FOR BIDDING ON INTERNATIONAL CONSTRUCTION PROJECTS

  • Wooyong Jung;Seung Heon Han
    • 국제학술발표논문집
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    • The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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    • pp.534-541
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    • 2011
  • Risk evaluation approaches for bidding on international construction projects are typically partitioned into three stages: country selection, project classification, and bid-cost evaluation. However, previous studies are frequently under attack in that they have several crucial limitations: 1) a dearth of studies about country selection risk tailored for the overseas construction market at a corporate level; 2) no consideration of uncertainties for input variable per se; 3) less probabilistic approaches in estimating a range of cost variance; and 4) less inclusion of covariance impacts. This study thus suggests a three-staged risk evaluation model to resolve these inherent problems. In the first stage, a country portfolio model that maximizes the expected construction market growth rate and profit rate while decreasing market uncertainty is formulated using multi-objective genetic analysis. Following this, probabilistic approaches for screening bad projects are suggested through applying various data mining methods such as discriminant logistic regression, neural network, C5.0, and support vector machine. For the last stage, the cost overrun prediction model is simulated for determining a reasonable bid cost, while considering non-parametric distribution, effects of systematic risks, and the firm's specific capability accrued in a given country. Through the three consecutive models, this study verifies that international construction risk can be allocated, reduced, and projected to some degree, thereby contributing to sustaining stable profits and revenues in both the short-term and the long-term perspective.

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IT 시대의 대체투자재가 근린상가 낙찰가율에 미치는 영향에 관한 연구 (Study on Effects of Alternative Investment Goods in the Era of IT in Relation to Bid Rate of Neighboring Shopping Area)

  • 정찬국;김동현
    • 한국전자통신학회논문지
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    • 제9권3호
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    • pp.377-386
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    • 2014
  • 본 연구는 근린상가 시장에 대한 대체투자재의 영향을 분석하여 근린상가의 투자시장과 관련된 이해당사자 들에게 합리적 의사결정의 기준을 제시하였으며, 근린상가 낙찰가율에 대한 영향의 형태와 설명력을 추정한 결과 다음과 같은 결론을 얻었다. 부동산 경기를 포함한 대표적인 거시경제지표인 종합주가지수와 지가변동률의 상승은 경기활성화의 방증으로 근린상가 시장에 긍정적인 영향을 미치나 대체투자재인 이자율의 상승은 근린상가에 대한 상대적 수익률을 감소시켜 근린상가시장의 투자에 대한 매력을 감소시킨다. 소비재 특성을 지닌 주택과 자본재 특성을 지닌 근린상가는 상호 영향적 측면에서 이질적인 시장으로 나타나 큰 영향을 미치지 않음을 알 수 있다.

위탁급식업체 선정에 영향을 미치는 요인에 대한 개발영업사원의 인식도 조사 (A Study on the Factors Affecting the Foodservice Management Contract Perceived by Salesperson of the Foodservice Company)

  • 김현아;양일선;이보숙;박진영
    • 대한영양사협회학술지
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    • 제10권2호
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    • pp.190-196
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    • 2004
  • The purposes of this study were to investigate the importance level on factors affecting the foodservice management contract perceived by the salespersons in the foodservice company. To get the data on the perceived importance level on the affecting the foodservice management contract, the questionnaires were developed by the delphi technique and modified by the pilot test. The questionnaires consisted of 4 categories and 19 items on the factors affecting the foodservice management contract and the importance level on the factors were measured by 5-likert scale. From March 12 to April 13 in 2003, the self-administrative questionnaires were mailed to the 60 salespersons. The questionnaires were responded from the 48 salespersons(respondent rate : 77 %). As a result, the salesperson.perceived importance level of "the sales ability" was higher than those of the other categories in the private contract and the salesperson.perceived importance level of "the evaluation of the foodservice company" was higher than those of the other categories in the competitive bid. The importance of the "the evaluation of the foodservice company" between the private contract and the competitive bid was significantly different(p<.05), and the importance of "the sales ability" of the competitive bid was significantly higher than that of the private contract(p<.001).

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자궁경부암 병기 IIB의 방사선치료결과 (Radiotherapy Results in Stage IIB Uterine Cervix Cancer)

  • 길훈종;전미선;강승희;오영택;유희석;주희재;이은주
    • Radiation Oncology Journal
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    • 제19권4호
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    • pp.345-352
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    • 2001
  • 목적 : 자궁경부암 병기 IIB 환자에서 근치적 목적의 방사선 단독 치료의 성적을 분석하고 예후 인자들을 확인하였다. 대상 및 방법 : 1994년 9월부터 1999년 12월까지 자궁 경부암으로 진단받고 방사선치료를 받은 환자들 중 FIGO병기 IIB 환자 90명을 대상으로 후향적 분석을 시행하였다. 환자들의 연령은 중앙값 57세($28\~79$세)였고, 종양의 크기는 최대 직경 4 cm 미만이 26명, 4 cm 이상이 64명이었다. 치료전 SCC 값(ng/ml) 측정이 75 명의 환자에서 시행되었고, 10 초과인 환자가 23 명이었다. 29명이 통상적 방사선치료(QD 치료군)를, 61 명이 변형된 다분할 방사선치료 (18 Gy/fx, 1일 1회, 10일간 $\rightarrow$ 1.5 Gy/fx, 1일 2회, 6일간:BID 치료군)를 받았다. BID 치료군 중 54명이 4 cm 이상의 종양을 가지고 있었다. $30.6\~39.6\;Gy$에서 골반 중심부 차폐를 하였고, 골반부위에 4 Gy까지 조사한 후 자궁주위 조직에 총 $49\~60\;Gy$ (중앙값 53 Gy)까지 추가 조사하였다. 근접 방사선치료는 A점에 4 Gy, 7회(52명) 또는 5 Gy, 6회(38명)를 시행하였다. 추적 관찰 기간은 38개월($9\~76$개월)이었다. 결과 : 5년 전체 생존율(OS)은 $73.4\%$, 무병 생존율(DFS)은 $71.6\%$이었다. 국소 재발(LR)은 9명$(10\%)$에서, 원격 전이(DM)는 17 명$(18.9\%)$에서 있었다. 그 중 3명은 LR과 DM가 동반되어 있었다. QD 군의 LR은 $17.2\%$ (5/29)에서, DM는 $10.3\%$ (3/29)에서 있었다. BID 군의 LR은 $6.6\%$ (4/61), DM은 $22.7\%$ (14/61)이었다. 5년 OS는 종양의 크기와 연관이 있었다.$(<4cm:95.2\%,\;\geq4cm:63.4\%,\;p<0.05)$. 반면에 5년 DFS은 종양의 크기 및 치료천 SCC 값과 유의한 상관 관계가 있었다$(<4cm:91.4\%,\;\geq4cm;63.4\%,\;SCC\;\leq10:76.4\%,\;SCC\;>10:53.1\%,\;p<0.05)$. 결론 : 종양의 크기가 큰 병기 IIB 자궁경부암에서 화학요법없이 변형된 다분할 방사선치료만을 시행하여 동시화학방사선요법의 결과와 비교할만한 좋은 5년 생존율을 얻었다. 특히 국소 재발율의 현저한 감소가 있었다$(7.4\%)$. 그러나 림프절 전이가 있는 4 cm 이상의 환자에서 $33\%$의 높은 원격 전이율을 보여, 이러한 고위험 환자군에서 화학요법의 추가가 도움이 될것으로 판단된다.

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화상부위에 이차감염이 발생한 개에서 Hydrophilic Polyurethane Foam의 임상적 적용 (Clinical Application of Hydrophilic Polyurethane Foam in a Dog with Secondary Infection in the Burned Area)

  • 김세은;심경미;배춘식;최석화;강성수
    • 한국임상수의학회지
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    • 제27권1호
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    • pp.121-124
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    • 2010
  • Thermal burn occurred in the anesthetized dog as a result of using hot pack to treat hypothermia. After hospital discharge, thermal burn leaded to secondary infection due to dog bites of the other dog in the house. After secondary infection, the treatment was performed with medication and bandaging. Because of the pain and infection from the wound, carprofen (2 mg/kg bid) and amoxicillin (20 mg/kg bid) were administrated orally for 40 days. And for 35 days, wet-to-dry gauze dressing was used to absorb purulent exudate. During this period, the burn eschar was removed completely from the burn site. After 35 days, the hydrophilic polyurethane foam ($Medifoam^{(R)}$, Ildong Pharm, Co., Korea) was admitted to the burn site for 30 days. $Medifoam^{(R)}$ made healing rate of the wound faster because the inner layer did not adhered to the wound, and newly formed tissue was protected. The second layer, hydrophilic absorptive layer absorbed excessive fluid and kept the wound surface moist. After 65 days after thermal burn, the wound was healed completely.

온라인 경매에의 카드깡 탐지요인에 대한 실증적 연구 (An Empirical Study on the Detection of Phantom Transaction in Online Auction)

  • 채명신;조형준;이병채
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2004년도 추계학술대회 및 정기총회
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    • pp.68-98
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    • 2004
  • Although the internet is useful for transferring information, Internet auction environments make fraud more attractive to offenders because the chance of detection and punishment are decreased. One of fraud is phantom transaction which is a colluding transaction by the buyer and seller to commit illegal discounting of credit card. They pretend to fulfill the transaction paid by credit card, without actual selling products, and the seller receives cash from credit card corporations. Then seller lends it out buyer with quite high interest rate whose credit score is so bad that he cannot borrow money from anywhere. The purpose of this study is to empirically investigate the factors to detect of the phantom transaction in online auction. Based up on the studies that explored behaviors of buyers and sellers in online auction, bidding numbers, bid increments, sellers' credit, auction length, and starting bids were suggested as independent variables. We developed an Internet-based data collection software agent and collect data on transactions of notebook computers each of which winning bid was over 1,000,000 won. Data analysis with logistic regression model revealed that starting bids, sellers' credit, and auction length were significant in detecting the phantom transaction.

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온라인 경매에서의 신용카드 허위거래 탐지 요인에 대한 실증 연구 (An Empirical Study on the Detection of Phantom Transaction in Online Auction)

  • 채명신;조형준;이병태
    • 경영과학
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    • 제21권2호
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    • pp.273-289
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    • 2004
  • Although the Internet is useful for transferring information, Internet auction environments make fraud more attractive to offenders, because the chance of detection and punishment is decreased. One of these frauds is the phantom transaction, which is a colluding transaction by the buyer and seller to commit the illegal discounting of a credit card. They pretend to fulfill the transaction paid by credit card, without actually selling products, and the seller receives cash from the credit card corporations. Then the seller lends it out with quite a high interest rate to the buyer, whose credit rating is so poor that he cannot borrow money from anywhere else. The purpose of this study is to empirically investigate the factors necessary to detect phantom transactions in an online auction. Based upon studies that have explored the behaviors of buyers and sellers in online auctions, the following have been suggested as independent variables: bidding numbers, bid increments, sellers' credit, auction lengths, and starting bids. In this study. we developed Internet-based data collection software and collected data on transactions of notebook computers, each of which had a winning bid of over W one million. Data analysis with a logistic regression model revealed that starting bids, sellers' credit, and auction length were significant in detecting the phantom transactions.

위탁급식 업체선정에 영향 미치는 요인에 대한 고객사의 중요도 인식 조사 (A Study of the Client′s Importance Perception on the Factors Affecting the Foodservice Management Contract)

  • 김현아;양일선;이보숙;박진영
    • Journal of Nutrition and Health
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    • 제37권5호
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    • pp.406-414
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    • 2004
  • The purposes of this study were 1) to investigate the importance level on factors affecting the foodservice management contract perceived by the clients in the office building, government and public offices and manufacturing company in Seoul and Kyungi 2) to compare the perceived importance levels of the present contract and future contract 3) to compare the perceived importance levels of the competitive bid with those of the private contract. To collect the data on the perceived importance level on the affecting the foodservice management contract, the questionnaires were developed by the delphi technique and modified by the pilot test. The questionnaires consisted of 4 categories and 19 items on the factors affecting the foodservice management contract and the importance level on the factors were measured by 5-likert scale. From March 12 to April 13 in 2003, the self-administrative questionnaires were mailed to 280 clients. The questionnaires were responded from the 50 clients (respondent rate: 25%). On the factors affecting the present contract and the future contract, among the 4 categories (the appropriateness of foodservice operation plan, the evaluation of the foodservice company, sales ability, the conditions of the cost in the contract), the importance level of the appropriateness of foodservice operation plan was higher than those of the other categories. In the comparison of the perceived importance level between the present contract and the future contract, the importance level of 4 items (sanitation and safety management plan, menu management plan, service management plan, food cost per meal) in the future contract were significantly higher than those in the present contract (p<.01, p<.05, p<.05, p<.01). There were the significant differences between the private contract and competitive bid on the factors affecting the present contract in the 3 items, which were $\ulcorner$renewal plan for interior and environment$\lrcorner$, $\ulcorner$strategic alliance with the contractor$\lrcorner$, $\ulcorner$lobby of the foodservice company$\lrcorner$ (p<.05, p<.05, p<.05). And on the factors affecting the future contract, there were significant differences in the 2 items, which were $\ulcorner$renewal plan for interior and environment$\lrcorner$and $\ulcorner$cost per meal$\lrcorner$in comparing the competitive bid and private contract (p<.05, p<.01). The clients perceived the appropriateness of foodservice operation plan was more important than the other categories in the future foodservice management contract. It was proposed that the foodservice management contract company should focus on the foodservice operation to satisfy the customers and clients in order to get more contract in the future.