• Title/Summary/Keyword: Size-based selection

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A Contingent Study of Information System Planning (정보시스템 계획의 상황적인 연구)

  • Cho Hyun-Dal
    • Management & Information Systems Review
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    • v.4
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    • pp.137-159
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    • 2000
  • Recently, the importance of ISP(Information System Planning) has been increased because of rapid change and severe competition in business environments. Furthermore, the role of IS in the organization has included not only the supportive activities but also the strategic activities. Organizations can get the competitive advantages through the strategic use of IT by establishing effective and systematic ISP implementation. The main focus of this study is investigate the relationship among three subunits(organizational factors, the role of IS and effective ISP) based on the contingent settings which the process of ISP is implemented. The reasons that conceptual framework of this study is based on the contingent theory are as follow: First, ISP process itself has a series of complicated work which various elements in a company are involved. ISP externally must have the process to evaluate information technology (technology related with IS). Internally ISP process has a serious of works including determining information requirements to develop successful IS for other functional departments and identifying strategic opportunity of IS aligned with business strategy. Secondly, the activity of ISP is occurring on the continual basis. Business environments in which ISP process has implemented are changing continuously. Specific ISP methodology which was appropriate in a certain period of time does not work any more because of the rapid changes in business environments. For this reason managers can hardly expect successful ISP without considering external environments or internal environments such as organizational or management side. For this study, 240 survey questionnaires were mailed and 71 questionnaires were returned. 57 samples were used for the final analysis and 14 samples were excluded from analysis in that they didn't exercise official and systematic ISP. As the result of analysis, among the internal factors(organizational size, time frame of decision making, budget, management style, organizational culture) organizational culture, management style and time frame of decision making are identified as contingent factors on the effective ISP. The result of this study may have meaning in suggesting the way to develop effective ISP through the formalization of business process, more favorable users attitude toward IS and selection of an appropriate ISP methodology.

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Tangible Interaction : Application for A New Interface Method for Mobile Device -Focused on development of virtual keyboard using camera input - (체감형 인터랙션 : 모바일 기기의 새로운 인터페이스 방법으로서의 활용 -카메라 인식에 의한 가상 키보드입력 방식의 개발을 중심으로 -)

  • 변재형;김명석
    • Archives of design research
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    • v.17 no.3
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    • pp.441-448
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    • 2004
  • Mobile devices such as mobile phones or PDAs are considered as main interlace tools in ubiquitous computing environment. For searching information in mobile device, it should be possible for user to input some text as well as to control cursor for navigation. So, we should find efficient interlace method for text input in limited dimension of mobile devices. This study intends to suggest a new approach to mobile interaction using camera based virtual keyboard for text input in mobile devices. We developed a camera based virtual keyboard prototype using a PC camera and a small size LCD display. User can move the prototype in the air to control the cursor over keyboard layout in screen and input text by pressing a button. The new interaction method in this study is evaluated as competitive compared to mobile phone keypad in left input efficiency. And the new method can be operated by one hand and make it possible to design smaller device by eliminating keyboard part. The new interaction method can be applied to text input method for mobile devices requiring especially small dimension. And this method can be modified to selection and navigation method for wireless internet contents on small screen devices.

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A New Deadlock Detection Mechanism in Wormhole Networks (웜홀 네트웍을 위한 새로운 교착상태 발견 기법)

  • Lee, Su-Jung
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.5_6
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    • pp.280-289
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    • 2003
  • Deadlock recovery-based routing algorithms in wormhole networks have gained attraction due to low hardware complexity and high routing adaptability Progressive deadlock recovery techniques require a few dedicated resources to transmit deadlocked packets rather than killing them. Selection of deadlocked packets is primarily based on time-out value which should be carefully determined considering various traffic patterns or packet length. By its nature, current techniques using time-out accompany unignorable number of false deadlock detections especially in a heavy-loaded network or with long packet size. Moreover, when a deadlock occurs, more than one packet may be marked as deadlocked, which saturate the resources allocated for recovery. This paper proposes more accurate deadlock detection scheme which does not make use of time-out to declare deadlock. The proposed scheme reduces the probability to detect false deadlocks considerably. Furthermore, a single message is selected as deadlocked for each cycle of blocked messages, thereby eliminating recovery overheads.

Rotation-Invariant Iris Recognition Method Based on Zernike Moments (Zernike 모멘트 기반의 회전 불변 홍채 인식)

  • Choi, Chang-Soo;Seo, Jeong-Man;Jun, Byoung-Min
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.2
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    • pp.31-40
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    • 2012
  • Iris recognition is a biometric technology which can identify a person using the iris pattern. It is important for the iris recognition system to extract the feature which is invariant to changes in iris patterns. Those changes can be occurred by the influence of lights, changes in the size of the pupil, and head tilting. In this paper, we propose a novel method based on Zernike Moment which is robust to rotations of iris patterns. we utilized a selection of Zernike moments for the fast and effective recognition by selecting global optimum moments and local optimum moments for optimal matching of each iris class. The proposed method enables high-speed feature extraction and feature comparison because it requires no additional processing to obtain the rotation invariance, and shows comparable performance to the well-known previous methods.

Repair of sports bone injury based on multifunctional nanomaterial particles

  • Dongbai Guo
    • Structural Engineering and Mechanics
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    • v.86 no.4
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    • pp.487-501
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    • 2023
  • Nanoparticles have lower size and larger specific surface area, good stability and less toxic and side effects. In recent years, with the development of nanotechnology, its application range has become wider and wider, especially in the field of biomedicine, which has received more and more attention. Bone defect repair materials with high strength, high elasticity and high tissue affinity can be prepared by nanotechnology. The purpose of this paper was to study how to analyze and study the composite materials for sports bone injury based on multifunctional nanomaterials, and described the electrospinning method. In this paper, nano-sized zirconia (ZrO2) filled micro-sized hydroxyapatite (HAP) composites were prepared according to the mechanical properties of bone substitute materials in the process of human rehabilitation. Through material tensile and compression experiments, the performance parameters of ZrO2/HAP composites with different mass fraction ratios were analyzed, the influence of filling ZrO2 particles on the mechanical properties of HAP matrix materials was clarified, and the effect of ZrO2 mass fraction on the mechanical properties of matrix materials was analyzed. From the analysis of the compressive elastic modulus, when the mass fraction of ZrO2 was 15%, the compressive elastic modulus of the material was 1222 MPa, and when 45% was 1672 MPa. From the analysis of compression ratio stiffness, when the mass fraction of ZrO2 was 15%, the compression ratio stiffness was 658.07 MPa·cm3/g, and when it was 45%, the compression ratio stiffness is 943.51MPa·cm3/g. It can be seen that by increasing the mass fraction of ZrO2, the stiffness of the composite material can be effectively increased, and the ability of the material to resist deformation would be increased. Typically, the more stressed the bone substitute material, the greater the stiffness of the compression ratio. Different mass fractions of ZrO2/HAP filling materials can be selected to meet the mechanical performance requirements of sports bone injury, and it can also provide a reference for the selection of bone substitute materials for different patients.

Development of Forest Road Network Model Using Digital Terrain Model (수치지형(數値地形)모델을 이용(利用)한 임도망(林道網) 배치(配置)모델의 개발(開發))

  • Lee, Jun Woo
    • Journal of Korean Society of Forest Science
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    • v.81 no.4
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    • pp.363-371
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    • 1992
  • This study was aimed at developing a computer model to determine rational road networks in mountainous forests. The computer model is composed of two major subroutines for digital terrain analyses and route selection. The digital terrain model(DTM) provides various information on topographic and vegetative characteristics of forest stands. The DTM also evaluates the effectiveness of road construction based on slope gradients. Using the results of digital terrain analyses, the route selection subroutine, heuristically, determines the optimal road layout satisfying the predefined road densities. The route selection subroutine uses the area-partitioning method in order to fully of roads. This method leads to unbiased road layouts in forest areas. The size of the unit partitiones area can be calculated as a function of the predefined road density. In addition, the user-defined road density of the area-partitioning method provides flexibility in applying the model to real situations. The rational road network can be easily achived for varying road densities, which would be an essential element for network design of forest roads. The optimality conditions are evaluated in conjuction with longitudinal gradients, investment efficiency earthwork quantity or the mixed criteria of these three. The performance of the model was measured and, then, compared with those of conventional ones in terns of average skidding distance, accessibility of stands, development index and circulated road network index. The results of the performance analysis indicate that selection of roading routes for network design using the digital terrain analysis and the area-partitioning method improves performance of the network design medel.

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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 Suggestion of Mix, Construction Method and Quality Control Criteria of Fine-size Exposed Aggregate PCC Pavement by Experimental Construction (시험시공을 통한 소입경 골재노출 콘크리트 포장의 배합, 시공 및 품질관리 기준 제안)

  • Lee, Seung-Woo;Kim, Young-Kyu;Choi, Don-Hwa;Shim, Jae-Won;Yoo, Tae-Seok
    • International Journal of Highway Engineering
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    • v.13 no.3
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    • pp.51-63
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    • 2011
  • Surface of fine-size exposed aggregate portland cement concrete pavements(FS-EAPCC) is consist by exposed coarse aggregate to remove upper 2~3mm mortar of concrete slabs. Advantages of FS-EAPCC are maintaining low-noise and adequate skid-resistance level during the performance period. However, FS-EAPCC is required rational management criteria for field application, since it is early stage for application. Design construction and quality control criteria of FS-EAPCC was temporary laboratory tests which including optimum mix and exposing method, selection of adequate aggregate, resistance against, environmental loading and etc. However, these criteria need to be validated base on field application. In this study, experimental constructions were performed and construction procedure and quality control criteria were suggested based on the performance of the FS-EAPCC.

Mesh Selectivity in Trammel Net for Flat Fish (가자미 삼중자망의 망목 선택성)

  • 김성훈;이주희
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.38 no.2
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    • pp.91-100
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    • 2002
  • The field experiments were carried out to examine for the mesh selectivity in trammel net and optimum mesh size, during Aug. 10~13, Non 9~13 2000 in Jumunjin, Kangwon-Do and during Jun. 1~27 2001 in Suyong-Bay, Busan. The experiments in Jumunjin area were conducted by using trammel nets with seven different mesh sizes (60, 75, 90, 105, 135, 150, 180mm) and those in Suyong-Bay were done by using trammel nets and gill nets with three different mesh sizes (60, 75, 90mm) in order to compare two types of nets of same structure. The mesh selectivity analysis was done mainly with flat fish(Eopsetta grigorjewi) that was occupied 60% out of total catches. And the mesh selectivity was written by extension of Kitahara's method included master curve with function type. The results obtained are summarized as follows 1. Total number of catch by, trammel net was 2,331 and that of gill net was 1,433, and flat fishes occupied 59.8 ~60% in total catches. 2. The value of optimum l/m by, trammel net was higher about 0.1 than that of gill net according as trammel net was 2.56, and gill net was 2.47. 3. The 50% selection range by, trammel net was wider about 1.5 time than that of gill net according as trammel net was 1.88~3.36(1.48) and gill net was 2.00~3.02(1.02). 4. The optimum mesh size(OMS) was estimated that trammel net was about 141mm and gill net was about 132mm on first maturity length(FML) 265mm of flat fish. 5. On the optimum mesh size based on the first maturity length of flat fish, The 50% range by, trammel net was wider about 76mm than that of gill net according as trammel net was 265 mm~474mm and gill net was 265mm~398mm.

Non-Contrast Cine Cardiac Magnetic Resonance Derived-Radiomics for the Prediction of Left Ventricular Adverse Remodeling in Patients With ST-Segment Elevation Myocardial Infarction

  • Xin A;Mingliang Liu;Tong Chen;Feng Chen;Geng Qian;Ying Zhang;Yundai Chen
    • Korean Journal of Radiology
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    • v.24 no.9
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    • pp.827-837
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    • 2023
  • Objective: To investigate the predictive value of radiomics features based on cardiac magnetic resonance (CMR) cine images for left ventricular adverse remodeling (LVAR) after acute ST-segment elevation myocardial infarction (STEMI). Materials and Methods: We conducted a retrospective, single-center, cohort study involving 244 patients (random-split into 170 and 74 for training and testing, respectively) having an acute STEMI (88.5% males, 57.0 ± 10.3 years of age) who underwent CMR examination at one week and six months after percutaneous coronary intervention. LVAR was defined as a 20% increase in left ventricular end-diastolic volume 6 months after acute STEMI. Radiomics features were extracted from the oneweek CMR cine images using the least absolute shrinkage and selection operator regression (LASSO) analysis. The predictive performance of the selected features was evaluated using receiver operating characteristic curve analysis and the area under the curve (AUC). Results: Nine radiomics features with non-zero coefficients were included in the LASSO regression of the radiomics score (RAD score). Infarct size (odds ratio [OR]: 1.04 (1.00-1.07); P = 0.031) and RAD score (OR: 3.43 (2.34-5.28); P < 0.001) were independent predictors of LVAR. The RAD score predicted LVAR, with an AUC (95% confidence interval [CI]) of 0.82 (0.75-0.89) in the training set and 0.75 (0.62-0.89) in the testing set. Combining the RAD score with infarct size yielded favorable performance in predicting LVAR, with an AUC of 0.84 (0.72-0.95). Moreover, the addition of the RAD score to the left ventricular ejection fraction (LVEF) significantly increased the AUC from 0.68 (0.52-0.84) to 0.82 (0.70-0.93) (P = 0.018), which was also comparable to the prediction provided by the combined microvascular obstruction, infarct size, and LVEF with an AUC of 0.79 (0.65-0.94) (P = 0.727). Conclusion: Radiomics analysis using non-contrast cine CMR can predict LVAR after STEMI independently and incrementally to LVEF and may provide an alternative to traditional CMR parameters.