• 제목/요약/키워드: selection principle

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Deveolping clinical pathways of acute appendicitis patients in emergency room (응급실 급성 충수염 환자의 임상경로 개발)

  • Park, Cheol-Yong;Kim, Yoon-Nyun;Choi, Hyun-Seok;Shin, A-Mi
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.3
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    • pp.427-435
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    • 2010
  • In this study, we develop clinical pathways for test and medical treatment items of acute appendicitis patients in emergency room. In order to develop the clinical pathways, we first employ the order selection method by Park et al. (2010), and then display the selected orders in such a way that associated orders are tied together. More specifically the order selection method that we employ is based on lift and, starting from the orders with higher frequencies, sequentially removes the negatively associated orders with lift values less than 0.9. The way associated orders are selected and tied together is similar to that of the order selection method. More specifically, starting from the selected orders with higher frequencies, the orders with lift values greater than 1.1 are considered associated and displayed to the right of the corresponding order. Therefore, in the diagram of clinical pathways, the orders at the left hand side, in principle, are not associated with each other and upper orders have higher frequencies, and associated orders are located to the right of corresponding order at the left hand side and more left orders, in principle, have higher frequencies.

Temporal distritution analysis of design rainfall by significance test of regression coefficients (회귀계수의 유의성 검정방법에 따른 설계강우량 시간분포 분석)

  • Park, Jin Heea;Lee, Jae Joon
    • Journal of Korea Water Resources Association
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    • v.55 no.4
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    • pp.257-266
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    • 2022
  • Inundation damage is increasing every year due to localized heavy rain and an increase of rainfall exceeding the design frequency. Accordingly, the importance of hydraulic structures for flood control and defense is also increasing. The hydraulic structures are designed according to its purpose and performance, and the amount of flood is an important calculation factor. However, in Korea, design rainfall is used as input data for hydrological analysis for the design of hydraulic structures due to the lack of sufficient data and the lack of reliability of observation data. Accurate probability rainfall and its temporal distribution are important factors to estimate the design rainfall. In practice, the regression equation of temporal distribution for the design rainfall is calculated using the cumulative rainfall percentage of Huff's quartile method. In addition, the 6th order polynomial regression equation which shows high overall accuracy, is uniformly used. In this study, the optimized regression equation of temporal distribution is derived using the variable selection method according to the principle of parsimony in statistical modeling. The derived regression equation of temporal distribution is verified through the significance test. As a result of this study, it is most appropriate to derive the regression equation of temporal distribution using the stepwise selection method, which has the advantages of both forward selection and backward elimination.

Combining A* and Genetic Algorithm for Efficient Path Search (효율적인 경로 탐색을 위한 A*와 유전자 알고리즘의 결합)

  • Kim, Kwang Baek
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.7
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    • pp.943-948
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    • 2018
  • In this paper, we propose a hybrid approach of combining $A^*$ and Genetic algorithm in the path search problem. In $A^*$, the cost from a start node to the intermediate node is optimized in principle but the path from that intermediate node to the goal node is generated and tested based on the cumulated cost and the next node in a priority queue is chosen to be tested. In that process, we adopt the genetic algorithm principle in that the group of nodes to generate the next node from an intermediate node is tested by its fitness function. Top two nodes are selected to use crossover or mutation operation to generate the next generation. If generated nodes are qualified, those nodes are inserted to the priority queue. The proposed method is compared with the original sequential selection and the random selection of the next searching path in $A^*$ algorithm and the result verifies the superiority of the proposed method.

An Analysis of Theoretical Orientations and Methodologies of Archival Appraisal (기록평가의 이론적 지향과 방법론 분석)

  • Seol, Moon-Won
    • The Korean Journal of Archival Studies
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    • no.75
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    • pp.5-39
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    • 2023
  • More than 20 years after introducing the public records management system in Korea, the criteria and methodologies for archival appraisal and selection are still unclear. Modern archival appraisal theories have developed in two orientations, such as provenance and pertinence. This study aims to investigate the methodological implications of each theoretical orientation of archival appraisal and to suggest some directions for improving the appraisal practices and policies. Firstly, archival appraisal theories are analyzed according two orientations. Secondly, four methodologies are derived from combining the macro/micro dimension and theoretical orientations. Thirdly, the methodological orientations of the criteria for selecting permanent records presented in the Public Records Management Act are analyzed. Finally, based on these analyses, appraisal policies and practices for selecting the records with permanent value are proposed to be improved.

Selection Criteria of Target Systems for Quality Management of National Defense Data (국방데이터 품질관리를 위한 대상 체계 선정 기준)

  • Jiseong Son;Yun-Young Hwang
    • Journal of Internet Computing and Services
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    • v.24 no.6
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    • pp.155-160
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    • 2023
  • In principle, data from all databases and systems managed by the Ministry of Defense or public institutions must be guaranteed to have a certain level of quality or higher, but since most information systems are built and operated, data quality management for all systems is realistically limited. Most defense data is not disclosed due to the nature of the work, and many systems are strategically developed or integrated and managed by the military depending on the need and importance of the work. In addition, many types of data that require data quality management are being accumulated and generated, such as sensor data generated from weapon systems, unstructured data, and artificial intelligence learning data. However, there is no data quality management guide for defense data and a guide for selecting quality control targets, and the selection criteria are ambiguous to select databases and systems for quality control of defense data according to the standards of the public data quality management manual. Depends on the person in charge. Therefore, this paper proposes criteria for selecting a target system for quality control of defense data, and describes the relationship between the proposed selection criteria and the selection criteria in the existing manual.

Discriminative Power Feature Selection Method for Motor Imagery EEG Classification in Brain Computer Interface Systems

  • Yu, XinYang;Park, Seung-Min;Ko, Kwang-Eun;Sim, Kwee-Bo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.13 no.1
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    • pp.12-18
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    • 2013
  • Motor imagery classification in electroencephalography (EEG)-based brain-computer interface (BCI) systems is an important research area. To simplify the complexity of the classification, selected power bands and electrode channels have been widely used to extract and select features from raw EEG signals, but there is still a loss in classification accuracy in the state-of- the-art approaches. To solve this problem, we propose a discriminative feature extraction algorithm based on power bands with principle component analysis (PCA). First, the raw EEG signals from the motor cortex area were filtered using a bandpass filter with ${\mu}$ and ${\beta}$ bands. This research considered the power bands within a 0.4 second epoch to select the optimal feature space region. Next, the total feature dimensions were reduced by PCA and transformed into a final feature vector set. The selected features were classified by applying a support vector machine (SVM). The proposed method was compared with a state-of-art power band feature and shown to improve classification accuracy.

Hopf Bifurcation Study of Inductively Coupled Power Transfer Systems Based on SS-type Compensation

  • Xia, Chenyang;Yang, Ying;Peng, Yuxiang;Hu, Aiguo Patrick
    • Journal of Power Electronics
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    • v.19 no.3
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    • pp.655-664
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    • 2019
  • In order to analyze the nonlinear phenomena of the bifurcation and chaos caused by the switching of nonlinear switching devices in inductively coupled power transfer (ICPT) systems, a Jacobian matrix model, based on discrete mapping numerical modeling, is established to judge the system stability of the periodic closed orbit and to study the nonlinear behavior of Hopf bifurcation in a system under full resonance. The general flow of the parameter design, based on the stability principle for ICPT systems, is proposed to avoid the chaos and bifurcation phenomena caused by unreasonable parameter selection. Firstly, based on the state equation of SS-type compensation, a three-dimensional bifurcation diagram with the coupling coefficient as the bifurcation parameter is established with a numerical simulation to observe the nonlinear phenomena in the system. Then Filippov's method based on a Jacobian matrix model is adopted to deduce the boundary of stable operation and to judge the type of the bifurcation in the system. Then the general flow of the parameter design based on the stability principle for ICPT systems is proposed through the above analysis to realize stable operation under the conditions of weak coupling. Finally, an experimental platform is built to confirm the correctness of the numerical simulation and modeling.

A Study on the Clinical Application of Five-Transport-Points in Huangdineijing - Focused on Frequency of Application and Selection (황제내경의 오수혈 임상 활용 연구 - 사용 빈도와 선혈을 중심으로)

  • Kim, Do-Hoon;Baik, Yousang
    • Korean Journal of Acupuncture
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    • v.37 no.4
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    • pp.276-283
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    • 2020
  • Objectives : In each section of Huangdineijing, we reviewed how the actual clinical application of Five-Transport-points was reflected and looked at the pattern of the application at the time. Methods : The contents related to Five-Transport-points in Huangdineijing were collected from each part, and analyzed. Results : There was a great difference in the number and contents of the clinical application of each Five-Transport-point for each 12 meridian, and only 28.3% of all Five-Transport-points had been related to clinical treatment. In addition, in specific applications, spring point, stream point, and sea point were used more often than well point, and Five-Transport-points between the same meridian or different meridians were used in combination as needed. Conclusions : Five-Transport-points described in Huangdineijing are intended to be operated within the overall framework structurally or functionally with a certain principle, but as a result of comprehensive analysis of specific examples of clinical application, there was a difference in the application between Five-Transport-points. This indicates that at the time of the establishment of Huangdineijing, which was the early stage of the development of Traditional East Asian Medicine, a variety of miscellaneous acupuncture methodologies were used in addition to those based on five elements principle.

Time Series Data Cleaning Method Based on Optimized ELM Prediction Constraints

  • Guohui Ding;Yueyi Zhu;Chenyang Li;Jinwei Wang;Ru Wei;Zhaoyu Liu
    • Journal of Information Processing Systems
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    • v.19 no.2
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    • pp.149-163
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    • 2023
  • Affected by external factors, errors in time series data collected by sensors are common. Using the traditional method of constraining the speed change rate to clean the errors can get good performance. However, they are only limited to the data of stable changing speed because of fixed constraint rules. Actually, data with uneven changing speed is common in practice. To solve this problem, an online cleaning algorithm for time series data based on dynamic speed change rate constraints is proposed in this paper. Since time series data usually changes periodically, we use the extreme learning machine to learn the law of speed changes from past data and predict the speed ranges that change over time to detect the data. In order to realize online data repair, a dual-window mechanism is proposed to transform the global optimal into the local optimal, and the traditional minimum change principle and median theorem are applied in the selection of the repair strategy. Aiming at the problem that the repair method based on the minimum change principle cannot correct consecutive abnormal points, through quantitative analysis, it is believed that the repair strategy should be the boundary of the repair candidate set. The experimental results obtained on the dataset show that the method proposed in this paper can get a better repair effect.

Selecting Climate Change Scenarios Reflecting Uncertainties (불확실성을 고려한 기후변화 시나리오의 선정)

  • Lee, Jae-Kyoung;Kim, Young-Oh
    • Atmosphere
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    • v.22 no.2
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    • pp.149-161
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    • 2012
  • Going by the research results of the past, of all the uncertainties resulting from the research on climate change, the uncertainty caused by the climate change scenario has the highest degree of uncertainty. Therefore, depending upon what kind of climate change scenario one adopts, the projection of the water resources in the future will differ significantly. As a matter of principle, it is highly recommended to utilize all the GCM scenarios offered by the IPCC. However, this could be considered to be an impractical alternative if a decision has to be made at an action officer's level. Hence, as an alternative, it is deemed necessary to select several scenarios so as to express the possible number of cases to the maximum extent possible. The objective standards in selecting the climate change scenarios have not been properly established and the scenarios have been selected, either at random or subject to the researcher's discretion. In this research, a new scenario selection process, in which it is possible to have the effect of having utilized all the possible scenarios, with using only a few principal scenarios and maintaining some of the uncertainties, has been suggested. In this research, the use of cluster analysis and the selection of a representative scenario in each cluster have efficiently reduced the number of climate change scenarios. In the cluster analysis method, the K-means clustering method, which takes advantage of the statistical features of scenarios has been employed; in the selection of a representative scenario in each cluster, the selection method was analyzed and reviewed and the PDF method was used to select the best scenarios with the closest simulation accuracy and the principal scenarios that is suggested by this research. In the selection of the best scenarios, it has been shown that the GCM scenario which demonstrated high level of simulation accuracy in the past need not necessarily demonstrate the similarly high level of simulation accuracy in the future and various GCM scenarios were selected for the principal scenarios. Secondly, the "Maximum entropy" which can quantify the uncertainties of the climate change scenario has been used to both quantify and compare the uncertainties associated with all the scenarios, best scenarios and the principal scenarios. Comparison has shown that the principal scenarios do maintain and are able to better explain the uncertainties of all the scenarios than the best scenarios. Therefore, through the scenario selection process, it has been proven that the principal scenarios have the effect of having utilized all the scenarios and retaining the uncertainties associated with the climate change to the maximum extent possible, while reducing the number of scenarios at the same time. Lastly, the climate change scenario most suitable for the climate on the Korean peninsula has been suggested. Through the scenario selection process, of all the scenarios found in the 4th IPCC report, principal climate change scenarios, which are suitable for the Korean peninsula and maintain most of the uncertainties, have been suggested. Therefore, it is assessed that the use of the scenario most suitable for the future projection of water resources on the Korean peninsula will be able to provide the projection of the water resources management that maintains more than 70~80% level of uncertainties of all the scenarios.