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Construction and Application of Intelligent Decision Support System through Defense Ontology - Application example of Air Force Logistics Situation Management System (국방 온톨로지를 통한 지능형 의사결정지원시스템 구축 및 활용 - 공군 군수상황관리체계 적용 사례)

  • Jo, Wongi;Kim, Hak-Jin
    • Journal of Intelligence and Information Systems
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    • v.25 no.2
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    • pp.77-97
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    • 2019
  • The large amount of data that emerges from the initial connection environment of the Fourth Industrial Revolution is a major factor that distinguishes the Fourth Industrial Revolution from the existing production environment. This environment has two-sided features that allow it to produce data while using it. And the data produced so produces another value. Due to the massive scale of data, future information systems need to process more data in terms of quantities than existing information systems. In addition, in terms of quality, only a large amount of data, Ability is required. In a small-scale information system, it is possible for a person to accurately understand the system and obtain the necessary information, but in a variety of complex systems where it is difficult to understand the system accurately, it becomes increasingly difficult to acquire the desired information. In other words, more accurate processing of large amounts of data has become a basic condition for future information systems. This problem related to the efficient performance of the information system can be solved by building a semantic web which enables various information processing by expressing the collected data as an ontology that can be understood by not only people but also computers. For example, as in most other organizations, IT has been introduced in the military, and most of the work has been done through information systems. Currently, most of the work is done through information systems. As existing systems contain increasingly large amounts of data, efforts are needed to make the system easier to use through its data utilization. An ontology-based system has a large data semantic network through connection with other systems, and has a wide range of databases that can be utilized, and has the advantage of searching more precisely and quickly through relationships between predefined concepts. In this paper, we propose a defense ontology as a method for effective data management and decision support. In order to judge the applicability and effectiveness of the actual system, we reconstructed the existing air force munitions situation management system as an ontology based system. It is a system constructed to strengthen management and control of logistics situation of commanders and practitioners by providing real - time information on maintenance and distribution situation as it becomes difficult to use complicated logistics information system with large amount of data. Although it is a method to take pre-specified necessary information from the existing logistics system and display it as a web page, it is also difficult to confirm this system except for a few specified items in advance, and it is also time-consuming to extend the additional function if necessary And it is a system composed of category type without search function. Therefore, it has a disadvantage that it can be easily utilized only when the system is well known as in the existing system. The ontology-based logistics situation management system is designed to provide the intuitive visualization of the complex information of the existing logistics information system through the ontology. In order to construct the logistics situation management system through the ontology, And the useful functions such as performance - based logistics support contract management and component dictionary are further identified and included in the ontology. In order to confirm whether the constructed ontology can be used for decision support, it is necessary to implement a meaningful analysis function such as calculation of the utilization rate of the aircraft, inquiry about performance-based military contract. Especially, in contrast to building ontology database in ontology study in the past, in this study, time series data which change value according to time such as the state of aircraft by date are constructed by ontology, and through the constructed ontology, It is confirmed that it is possible to calculate the utilization rate based on various criteria as well as the computable utilization rate. In addition, the data related to performance-based logistics contracts introduced as a new maintenance method of aircraft and other munitions can be inquired into various contents, and it is easy to calculate performance indexes used in performance-based logistics contract through reasoning and functions. Of course, we propose a new performance index that complements the limitations of the currently applied performance indicators, and calculate it through the ontology, confirming the possibility of using the constructed ontology. Finally, it is possible to calculate the failure rate or reliability of each component, including MTBF data of the selected fault-tolerant item based on the actual part consumption performance. The reliability of the mission and the reliability of the system are calculated. In order to confirm the usability of the constructed ontology-based logistics situation management system, the proposed system through the Technology Acceptance Model (TAM), which is a representative model for measuring the acceptability of the technology, is more useful and convenient than the existing system.

A Study on the Framework of Cutover Decision Making on Large-scale IS Development Projects: A Core Banking Development Case of D Bank (대규모 정보시스템 개발 프로젝트의 컷오버 의사결정 프레임워크에 관한 연구: D은행 코어뱅킹 시스템 구축 사례를 중심으로)

  • Jeong, Cheon-Su;Ahn, Hyun-Chul;Jeong, Seung-Ryul
    • Information Systems Review
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    • v.14 no.1
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    • pp.1-19
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    • 2012
  • A large-scale IS development project takes a long time, thus its project manager needs to be more careful on risk management. In particular, appropriate cutover decision making is critical in large-scale IS development projects because the opening of the large-scale IS significantly impacts the organization. Regardless of its importance, cutover decision making in conventional IS development projects has been done in a quite simple way. Conventional cutover decisions have been made by considering just whether the new IS operates or not from the system, application, and data implementation perspectives. However, this approach may lead to unsatisfactory performance or system failure in complex large-scale IS development. Under this background, we propose a new framework for cutover decision making on large-scale IS projects. To validate the applicability, we applied the framework to a core banking system development case. The case study shows that our framework is effective in proper cutover decision making.

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Data Deduplication Method using PRAM Cache in SSD Storage System (SSD 스토리지 시스템에서 PRAM 캐시를 이용한 데이터 중복제거 기법)

  • Kim, Ju-Kyeong;Lee, Seung-Kyu;Kim, Deok-Hwan
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.4
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    • pp.117-123
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    • 2013
  • In the recent cloud storage environment, the amount of SSD (Solid-State Drive) replacing with the traditional hard disk drive is increasing. Management of SSD for its space efficiency has become important since SSD provides fast IO performance due to no mechanical movement whereas it has wearable characteristics and does not provide in place update. In order to manage space efficiency of SSD, data de-duplication technique is frequently used. However, this technique occurs much overhead because it consists of data chunking, hasing and hash matching operations. In this paper, we propose new data de-duplication method using PRAM cache. The proposed method uses hierarchical hash tables and LRU(Least Recently Used) for data replacement in PRAM. First hash table in DRAM is used to store hash values of data cached in the PRAM and second hash table in PRAM is used to store hash values of data in SSD storage. The method also enhance data reliability against power failure by maintaining backup of first hash table into PRAM. Experimental results show that average writing frequency and operation time of the proposed method are 44.2% and 38.8% less than those of existing data de-depulication method, respectively, when three workloads are used.

The Role of Angled Blade Plate in Treatment of Bone Tumor Occurred in Femur (대퇴골 골종양의 치료에 있어서의 Angled Blade Plate의 역할)

  • Kim, Tai-Seung;Kang, Chang-Nam;Chung, Ung-Seo
    • The Journal of the Korean bone and joint tumor society
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    • v.11 no.2
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    • pp.175-182
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    • 2005
  • Purpose: Bone tumor occurred in femur frequently involve proximal intertrochanteric region or distal metaphyseal region. Sometimes, the pathologic fracture can happen according to the size of tumor due to the substantial biomechanical stresses. Therefore, the prognosis can be improved biomechanically by the angled blade plate considering the anatomic configuration after the excision of tumor. Materials and Methods: Between October 1991 and April 2005, there were a total of 16 patients(17 cases) who were treated by the excision of tumor and internal fixation with the angled blade plate for bone tumor occurred in femur. After the excision of tumor, we filled the cavity by bone graft in 11 cases and bone cement in 6 cases. The internal fixation was used by angled blade plate in all cases. Result: The average follow-up time was 55.5 months(6-144 months) in 16 patients(17 cases). No metal failure occurred after the operation. Reoperation was performed in 4 cases due to tumor recurrence, and the internal fixation was firm until that. Conclusion: The angled blade plate can prevent the fracture until grafted bone incorporated to host bone, and protect fragile connection between cement and host bone.

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Study on Landslide Flume Tests Using Stability Analysis of the Unsaturated Infinite Slope (불포화 무한사면의 안정해석을 활용한 산사태 모형실험에 관한 연구)

  • Song, Hyo-Sung;Chae, Byung-Gon;Song, Young-Suk;Choi, Jung-Hae;Seo, Won-Gyo;Woo, Ik
    • The Journal of Engineering Geology
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    • v.29 no.4
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    • pp.541-552
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    • 2019
  • In this study, landslide flume tests were performed to analyze characteristics of ground characteristics and landslide occurrence due to rainfall infiltration. As test materials, weathered granite soil and gneiss soil, the most frequent landslides in Korea, were used, and landslides were triggered by heavy rain (Intensity = 200 mm/hr). The measurement sensors were installed with 3 sets at toe, slope, top part and shallow (GL-0.2 m), middle (GL-0.4 m), and deep (GL-0.6 m) depth in the slope and measured at 10 second intervals. After landslide flume tests, the slope stability analysis was performed by applying the unsaturated soil theory based on the change of ground characteristics and compared with actual landslide occurrence from flume test. As a result of the analysis, factor of safety reflected the landslide occurrence from flume test and factor of safety decreased as rainfall infiltration, leading to slope failure. Finally we compared to the factor of safety below 1 and actual landslide occurrence time, the average difference was 1,600 seconds for weathered granite soil and 5,400 seconds for weathered gneiss soil.

Development on Prediction Algorithm of Sediment Discharge by Debris Flow for Decision of Location and Scale of the Check Dam (사방댐 위치 및 규모 결정을 위한 토석류 토사유출량 예측 알고리즘 개발)

  • Kim, Kidae;Woo, Choongshik;Lee, Changwoo;Seo, Junpyo;Kang, Minjeng
    • Journal of the Society of Disaster Information
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    • v.16 no.3
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    • pp.586-593
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    • 2020
  • Purpose: This study aims to develop an algorithm for predicting sediment discharge by debris flow, and develop GIS-based decision support system for optimal arrangement of check dam. Method: The average stream width and flow length were used to predict the cumulative sediment discharge by debris flow. At this time, the amount of slope failure on source area and average flow length were utilized as input factors. Result: The predicted sediment discharge calculated through the algorithm was 1.1 times different on average compared to the actual sediment discharge by debris flow. In addition, the program is an objective indicator that selects the location and size of the check dam, and it can help practitioners make rational decisions. Conclusion: The soil erosion control works are being implemented every year. Therefore, it is expected that the GIS-based decision support system for location and size of the check dam will contribute to the prevention of sediment-related disasters.

A Surgical Treatment of Coronary artery Occlusive disease. (A Report of 8 cases) (관상동맥협착증의 외과적 치험)

  • 김병열
    • Journal of Chest Surgery
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    • v.21 no.6
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    • pp.1020-1029
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    • 1988
  • The authors evaluated 153 patients who had undergone cardiac valve replacement between October 1979 and July 1988. The results are as follows: l. Out of 153 patients, there were 56 males and 97 females ranging from 15 to 62 years of age with a mean of 37 years. 2. Isolated mitral valve replacement took place in 82 patients, aortic valve replacement[AVR] in 16, double valve replacement[DVR] in 34, AVR combined with open mitral commissurotomy in 19, and tricuspid valve replacement[TVR] was done in 2 patients. 3. 153 patients had 187 prosthetic valves replaced with Ionescu-Shiley valves[16], Carpentier-Edwards[36], Bjork-Shiley[19], St. Jude Medical[108], and Duromedics[8]. 4. Our of 98 patients with atrial fibrillation[ 64% of a total 153 patients ] during the preoperative period, 22 patients recovered NSR[ 22/98, NSR recovery rate 22.4%] after valvular surgery and remaining 76 patients revealed persisting atrial fibrillation[76/153, 49.7% ]. 5. Preoperative episodes of systemic arterial embolization were attained in 9 patients[9/153, 6% ], and left atrial thrombi were confirmed in 22 patients intraoperatively[ 22/153, 14% ]. Of these, only one patient, however, demonstrated the correspondence of preoperative embolization and intraoperative existence of LA thrombi. 6. With mechanical prostheses, anticoagulant therapy was begun 48 hours after operation with sodium warfarin[2.5-5.0mg/day], maintaining the prothrombin time between 16 and 18 seconds or 30 to 50% of control values and continued for life. With tissue prostheses, sodium warfarin was continued for 3 to 6 months and converted into buffered ASA[ 325 mg/day ] for one year. 7. The mean follow-up for the survivors was 30.1 months, with a range from 3 months to 9 years. All suspected or confirmed thromboembolic episodes counted as events and occurred in 4 patients[ 1.04%/patient-year] with mechanical valve replacement. No persistent paralysis or death was noted. Late complications have not yet occurred in the patients with isolated MVR and AVR. 8. There were remarkable structural failures of tissue valves in 3 patients[ 1.9%/patient-year ], while no instance of failure of a mechanical valve. 9. There were 10 operative early deaths[10/153, 6.5%] and 5 late deaths[5/153, 3.3%]. Consequently, overall mortality was 9.8%[ 15/153] during follow-up period. 10. We currently favor using the St. Jude Medical valve in all patients requiring valve replacement except in those who can not take warfarin anticoagulation.

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A Case Report of Heart-Lung Transplantation (심장-폐 이식 증례 보고)

  • 노준량;허재학;오삼세;김영태;이정렬;이기봉;오병희;한성구
    • Journal of Chest Surgery
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    • v.31 no.10
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    • pp.1004-1008
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    • 1998
  • We report a case of heart-lung transplantation in a 32 year-old female with Eisenmenger syndrome secondary to patent ductus arteriosus. She has been suffered from congestive heart failure since June 1996 and repeatedly treated at Intensive Care Unit with intravenous inotropic support since July 1997. Preoperative echocardiography showed a patent ductus arteriosus with right to left shunt, severe regurgitation of tricuspid valve and estimated right ventricular systolic pressure of 100mmHg. The brain-dead donor was an 18 year-old male with head trauma from traffic accident 3 days ago. Heart-lung block procurement was performed at another general hospital and was transported to the Seoul National University Hospital by ambulance. Total ischemic time of the transplanted heart and lung were 249 minutes and 270 minutes, respectively. The immunosuppressive therapy was commenced preoperatively with cyclosporine and azathioprine. Corticosteroid was not used until postoperative 3 weeks in order to avoid infection and delayed healing at the tracheal anastomotic site. The patient was discharged at 31st postoperative day, and has been regularly followed up at outpatient clinic without specific complication. The follow-up bronchoscopy, performed 2 weeks and 4 months after surgery, revealed no evidence of cellular rejection.

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CLINICAL CATEGORIES OF ADOLESCENT BORDERLINE STATE (청소년 경계선 상태의 임상적 분류)

  • Hong, Kang-E;Jeon, Seong-Ill;Shin, Min-Sup
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.6 no.1
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    • pp.18-33
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    • 1995
  • The Purpose of this article is to identify the specific characteristics of borderline disorder in adolescence to conceptualize the borderline state as an adolescent process different from borderline personality disorder in adult, and to classify them according to it's unique clinical feature, porcess and outcome. The development of borderline disorder in adolescent, epidemiology, comorbid disorders and differential diagnosis, pre-existing sub-classification systems, and etiology in theories of psychodynamics, biological theories, experimental studies, and follow-up studies are reviewed. The authors conceptualize the adolescent borderline state include all clinical states generated by re-emergence of unresolved rapproachement conflicts in adolescent, and propose that there are four subgroups in adolescent borderline state. (1) Borderline state as an adolescent process. (2) Borderline state associated with psychotic disorders (3) Borderline state as an initial stnge of typical borderline personality disorder (4) Borderline state associated with organic problems. Conceptually, borderline state in adolescence is not a simple continuation of primary failure of separation-individuation but a struggle for mastering unresolved separation-individuation conflicts in adolesance i.e., the second separation-individuation state, and if it fails this time, the struggle might continue into adult life as borderline personality disorder.

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Bioequivalence of Stapin ER Tablet to Splendil ER Tablet (Felodipine 5 mg) (스프렌딜 지속정(펠로디핀 5 mg)에 대한 스타핀 지속정의 생물학적동등성)

  • Cho, Hea-Young;Kang, Hyun-Ah;Lee, Suk;Baek, Seung-Hee;Park, Eun-Ja;Choi, Hoo-Kyun;Moon, Jai-Dong;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.33 no.4
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    • pp.311-317
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    • 2003
  • Felodipine is a calcium antagonist that lowers blood pressure by reducing peripheral resistance by meas of a direct, selective action on smooth muscle in arterial resistance vessels. Futhermore, it have been approved for the effective in angina pectoris and cardiac failure. The purpose of the present study was to evaluate the bioequivalence of two felodipine extended release (ER) tablets, Splendil (YuHan Corporation) and Stapin (Hana Pharmaceutial Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The felodipine release from the two felodipine formulations in vitro was tested using KP VIII Apparatus II method at pH 6.5 buffer solution. Twenty six healthy male subjects, $22.73{\pm}1.78$ years in age and $66.66{\pm}7.28\;kg$ in body weight, were divided into two groups and a radomized $2{\times}2$ cross-over study was employed. After two tablets containing 5 mg as felodipine were orally administered, blood sample was taken at predetermined time intervals and the concentrations of felodipine in serum were determined using column-switching HPLC method with UV detector. The dissolution profiles of two formulations were similar at pH 6.5 buffer solution. Besides, the pharmacokinetic parameters such as $AUC_t,\;C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t\;and\;C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the Splendil were 2.53%, 1.32% and 18.32% for $AUC_t,\;C_{max}\;and\;T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance rage of log(0.86) to log(1.25) $(e.g.,\;log(0.86){\sim}log(1.20)\;and\;log(0.89){\sim}log(1.23)\;for\;AUC_t,\;C_{max},\;respectively)$. Thus, the criteria of the KFDA guidelines for the bioequivalence was satisfied, indicating Stapin ER tablet and Splendil ER tablet are bioequivalent.