• Title/Summary/Keyword: Decision Making and Information Source

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A surrogate model-based framework for seismic resilience estimation of bridge transportation networks

  • Sungsik Yoon ;Young-Joo Lee
    • Smart Structures and Systems
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    • v.32 no.1
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    • pp.49-59
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    • 2023
  • A bridge transportation network supplies products from various source nodes to destination nodes through bridge structures in a target region. However, recent frequent earthquakes have caused damage to bridge structures, resulting in extreme direct damage to the target area as well as indirect damage to other lifeline structures. Therefore, in this study, a surrogate model-based comprehensive framework to estimate the seismic resilience of bridge transportation networks is proposed. For this purpose, total system travel time (TSTT) is introduced for accurate performance indicator of the bridge transportation network, and an artificial neural network (ANN)-based surrogate model is constructed to reduce traffic analysis time for high-dimensional TSTT computation. The proposed framework includes procedures for constructing an ANN-based surrogate model to accelerate network performance computation, as well as conventional procedures such as direct Monte Carlo simulation (MCS) calculation and bridge restoration calculation. To demonstrate the proposed framework, Pohang bridge transportation network is reconstructed based on geographic information system (GIS) data, and an ANN model is constructed with the damage states of the transportation network and TSTT using the representative earthquake epicenter in the target area. For obtaining the seismic resilience curve of the Pohang region, five epicenters are considered, with earthquake magnitudes 6.0 to 8.0, and the direct and indirect damages of the bridge transportation network are evaluated. Thus, it is concluded that the proposed surrogate model-based framework can efficiently evaluate the seismic resilience of a high-dimensional bridge transportation network, and also it can be used for decision-making to minimize damage.

Assessment of Breast Cancer Risk in an Iranian Female Population Using Bayesian Networks with Varying Node Number

  • Rezaianzadeh, Abbas;Sepandi, Mojtaba;Rahimikazerooni, Salar
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.11
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    • pp.4913-4916
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    • 2016
  • Objective: As a source of information, medical data can feature hidden relationships. However, the high volume of datasets and complexity of decision-making in medicine introduce difficulties for analysis and interpretation and processing steps may be needed before the data can be used by clinicians in their work. This study focused on the use of Bayesian models with different numbers of nodes to aid clinicians in breast cancer risk estimation. Methods: Bayesian networks (BNs) with a retrospectively collected dataset including mammographic details, risk factor exposure, and clinical findings was assessed for prediction of the probability of breast cancer in individual patients. Area under the receiver-operating characteristic curve (AUC), accuracy, sensitivity, specificity, and positive and negative predictive values were used to evaluate discriminative performance. Result: A network incorporating selected features performed better (AUC = 0.94) than that incorporating all the features (AUC = 0.93). The results revealed no significant difference among 3 models regarding performance indices at the 5% significance level. Conclusion: BNs could effectively discriminate malignant from benign abnormalities and accurately predict the risk of breast cancer in individuals. Moreover, the overall performance of the 9-node BN was better, and due to the lower number of nodes it might be more readily be applied in clinical settings.

Estimating the Weight of Ginseng Using an Image Analysis (영상 분석을 이용한 수삼의 중량추정)

  • Jeong, Seokhoon;Ko, Kuk Won;Lee, Ji-Yeon;Lee, Jinho;Seo, Hyeonseok;Lee, Sangjoon
    • KIPS Transactions on Software and Data Engineering
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    • v.5 no.7
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    • pp.333-338
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    • 2016
  • This study is to estimate proximity without direct measurement of the weight of fresh ginseng. For this work, we developed a ginseng image acquiring instrument and obtained 126 ginseng images using the instrument. Image analysis and parameter extraction process was used C language based Labwindows/CVI development tools and open source library OpenCV. Estimation formula is made by weighing the sample with image analysis of fresh ginseng. We analyzed the correlation between the pixel number and the weight of ginseng using a linear regression approach. It was obtained a strong positive correlation coefficient of 0.9162 with a linearity value.

The Prediction of DEA based Efficiency Rating for Venture Business Using Multi-class SVM (다분류 SVM을 이용한 DEA기반 벤처기업 효율성등급 예측모형)

  • Park, Ji-Young;Hong, Tae-Ho
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.139-155
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    • 2009
  • For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

A Study on the Systematic Integration of WASP5 Water Quality Model with a GIS (GIS와 WASP5 수질모델의 유기적 통합에 관한 연구)

  • 최성규;김계현
    • Spatial Information Research
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    • v.9 no.2
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    • pp.291-307
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    • 2001
  • In today's environmental engineering practice, many technologies such as GIS have been adopted to analyze chemical and biological process in water bodies and pollutants movements on the land surface. However, the linkage between spatially represented land surface pollutants and the in-stream processes has been relatively weak. This lack of continuity needs to develop a method in order to link the spatially-based pollutant source characterization with the water quality modeling. The objective of this thesis was to develop a two-way(forward and backward) link between ArcView GIS software and the USEPA water quality model, WASP5. This thesis includes a literature review, the determination of the point source and non-point source loadings from WASP5 modeling, and the linkage of a GIS with WASP5 model. The GIS and model linkage includes pre-processing of the input data within a GIS to provide necessary information for running a model in the forms of external input files. The model results has been post-processed and stored in the GIS database to be reviewed in a user defined form such as a chart, or a table. The interface developed from this study would provide efficient environment to support the easier decision making form water quality management.

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Efficiency Rating by Types of Public Institutions and Identification of Inefficiency Sources (공공기관의 유형별 효율성 평가와 비효율성 원인의 규명에 관한 연구)

  • Kim, Hyun Jung
    • Journal of the Korean Operations Research and Management Science Society
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    • v.40 no.1
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    • pp.75-89
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    • 2015
  • In recent years, attention to the high debt ratio in public institutions has pushed the government to make efforts in reducing the debt ratio. However, in order to stimulate the economy, the government needs drastically innovative measures that reduce debt by improving efficiency rather than moderate approaches that focus solely on debt reduction. Despite this need, no study has yet systematically analyzed the overall efficiency of domestic public institutions and identified the source of inefficiencies in each public entity. Therefore, largely two research questions are examined. First, this study compares the efficiency levels by types of public institutions. Second, this study identifies the cause of inefficiencies in each public institution and proposes directions for improving efficiency. Based on a 5-year data of 302 public institutions published in public business information systems and organizational websites from 2009 to 2013, Data Envelopment Analysis (DEA) was performed. The input variables include the number of employees and total costs while the output variables include sales and net income. Reflecting the characteristics of public institutions, the input-oriented CCR model and input-oriented BCC model were utilized. Analysis results are as follows. First, market-oriented public institutions showed the highest efficiency while fund management quasi-governmental agencies showed the highest inefficiency. Second, scale efficiency score was measured by applying the CCR model and the BCC model on the organizations with the lowest efficiency level, fund management quasi-governmental agencies. Based on these analysis results, the source of inefficiency and detailed directions for improvement were proposed for Decision Making Units (DMUs) with low CCR and BCC scores.

Exploring Purchase Behavior of Digital Items and Actual Usage in a Social Network Site: A Longitudinal Perspective (소셜 네트워크 서비스 사용자의 디지털 아이템 구매와 실제 사용에 관한 연구: 종단적 관점에서)

  • Kim, Byoung-Soo;Han, Se-Hee;Kang, Young-Sik
    • The Journal of Information Systems
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    • v.21 no.2
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    • pp.97-114
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    • 2012
  • Given the rapid growth of social network services (SNS) such as Facebook and Cyworld, it is important to understand SNS users' decision-making processes such as purchasing and continuance intention. Especially, as a number of SNS providers such as Cyworld and Habbo Hotel recognize the sales of digital items as the main source of their profits, it is critical to in-depth understand SNS users' purchasing behaviors. In this regard, this study explores continued usage behaviors and purchase behaviors of digital items in an SNS environment using a longitudinal research method. This paper develops a theoretical model to deeply understand the key drivers of purchase behavior of digital items through constructs prescribed by two established research streams on information systems, namely continuance usage and habitual usage. Moreover, this study examines the effects of actual and ideal self-image congruity on SNS continuance intention and habit. The research model was tested by using survey data collected from 307 users who have experience with Cyworld. The analysis results show that SNS actual usage directly influence purchase behavior of digital items. SNS users' continuance intention and habit are key drivers to enhance the level of actual usage of the SNS. Both actual and ideal self-image congruity play a key role in enhancing continuance usage and habitual usage. The implication of research and discussions provides reference for SNS providers in marketing and IT strategy.

YouTube videos provide low-quality educational content about rotator cuff disease

  • Kunze, Kyle N.;Alter, Kevin H.;Cohn, Matthew R.;Vadhera, Amar S.;Verma, Nikhil N.;Yanke, Adam B.;Chahla, Jorge
    • Clinics in Shoulder and Elbow
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    • v.25 no.3
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    • pp.217-223
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    • 2022
  • Background: YouTube has become a popular source of healthcare information in orthopedic surgery. Although quality-based studies of YouTube content have been performed for information concerning many orthopedic pathologies, the quality and accuracy of information on the rotator cuff have yet to be evaluated. The purpose of the current study was to evaluate the reliability and educational content of YouTube videos concerning the rotator cuff. Methods: YouTube was queried for the term "rotator cuff." The first 50 videos from this search were evaluated. Video reliability was assessed using the Journal of the American Medical Association (JAMA) benchmark criteria (range, 0-5). Educational content was assessed using the global quality score (GQS; range, 0-4) and the rotator cuff-specific score (RCSS; range, 0-22). Results: The mean number of views was 317,500.7±538,585.3. The mean JAMA, GQS, and RCSS scores were 2.7±2.0, 3.7±1.0, and 5.6±3.6, respectively. Non-surgical intervention content was independently associated with a lower GQS (β=-2.19, p=0.019). Disease-specific video content (β=4.01, p=0.045) was the only independent predictor of RCSS. Conclusions: The overall quality and educational content of YouTube videos concerned with the rotator cuff were low. Physicians should caution patients in using such videos as resources for decision-making and should counsel them appropriately.

A Basic Study on the Implementation of Knowledge Management for Design (디자인에 있어서 지식경영의 도입에 관한 기초연구)

  • 서홍석
    • Science of Emotion and Sensibility
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    • v.5 no.4
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    • pp.33-43
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    • 2002
  • The world is in the great change by the digital revolution and is changing fast to knowledge-based society beyond information society. That is to say, Knowledge is the most powerful source of competitiveness. This change of environment needs new paradigm in design. As of today, There is need to study systematically and approach practically about knowledge management. So that, we are intend to reconstruct theoretical system from design-oriented viewpoint and propose knowledge-creation paradigm through the importing technique of knowledge management into design. This study is to develop theoretical frame work of knowledge management in design as a basic study on the implementation of knowledge management for design. By the method of study for this, It was studied literature and precedent. Further more, proposed the appropriate direction of knowledge management implementation in design. Also, It was composed knowledge management system of the infra system, information system, decision-making support system and knowledge competency. Finally, The technical feature of knowledge management system was analyzed from a information technology point of view.

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A Study of Factors Influencing on Receivers' Communication Style in Internet Shopping Mall Contents (인터넷 쇼핑몰 콘텐츠에서 정보수신자의 커뮤니케이션 스타일에 미치는 영향요인에 관한 연구)

  • Chun Myung-Hwan
    • The Journal of the Korea Contents Association
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    • v.6 no.3
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    • pp.75-84
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    • 2006
  • The internet has the capabilities of supporting and facilitating several forms of consumer interaction including one-to-one, one to many, or many-to-many interactions. Especially, previous studies revealed that the Online Word-of-Mouth communication is widely used as a source of customer's information seeking and purchase decision making. Even with this importance of the Online Word-of-Mouth communication on internet, few research has systematically addressed the issue. This study investigates the effect of interpersonal communication on consumers' information search activities and develops a model that depicts the key antecedents and mediating variables of interpersonal communication in internet shopping environment. The results are as follows: First, choice uncertainty, perceived risk, and knowledge uncertainty play an important role for perceived usefulness. Second, perceived usefulness has directly affected interactive communication of consumers' communication style. Thus, it is essential for internet companies to find ways to encourage their customers to engage in word-of-mouth communication.

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