• Title/Summary/Keyword: Event Characteristic

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A Study to Improve the Database for the Efficiency on Railway Traffic Control System (철도관제 시스템의 효율성을 위한 데이터베이스 개선 방안 연구)

  • Jung, Hye-Ran;Cho, Woo-Sic
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.1275-1281
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    • 2011
  • Most of the railway traffic control systems are using in the DBMS(Database Management System)is a disk-based DBMS. When the train schedule and the event data is inputted and referred at real time on Disk-based DBMS, it is characteristic of the slow access time and the data is preserved permanently. For this reason, this paper suggests the way of improving for Railway Traffic Control System by the hybrid DBMS using a combination of memory and disk. We apply the Hybrid DBMS to Railway Traffic Control System and compare the existing method with suggested one using the same data. As a result of comparison, we have come to the conclusion that suggested method is far more performance to shorten data access time and process a mass information than the previous methods.

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African American Race and Low Income Neighborhoods Decrease Cause Specific Survival of Endometrial Cancer: A SEER Analysis

  • Cheung, Min Rex
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.4
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    • pp.2567-2570
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    • 2013
  • Background: This study analyzed Surveillance, Epidemiology and End Results (SEER) data to assess if socio-economic factors (SEFs) impact on endometrial cancer survival. Materials and Methods: Endometrial cancer patients treated from 2004-2007 were included in this study. SEER cause specific survival (CSS) data were used as end points. The areas under the receiver operating characteristic (ROC) curve were computed for predictors. Time to event data were analyzed with Kaplan-Meier method. Univariate and multivariate analyses were used to identify independent risk factors. Results: This study included 64,710 patients. The mean follow up time (S.D.) was 28.2 (20.8) months. SEER staging (ROC area of 0.81) was the best pretreatment predictor of CSS. Histology, grade, race/ethnicity and county level family income were also significant pretreatment predictors. African American race and low income neighborhoods decreased the CSS by 20% and 3% respectively at 5 years. Conclusions: This study has found significant endometrial survival disparities due to SEFs. Future studies should focus on eliminating socio-economic barriers to good outcomes.

Surgical Treatment of Supravalvular Aortic Stenosis - Report of a case - (대동맥 판상부 협착증 치험 1례)

  • 조영철
    • Journal of Chest Surgery
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    • v.22 no.4
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    • pp.680-686
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    • 1989
  • Supravalvular aortic stenosis may be defined as an obstructive congenital deformity of the ascending aorta which originates just distal to the level of the origin of the coronary arteries. It may occur in several different anatomical form. Three type have been described; the hourglass, the hypoplastic and the membranous type, each term identifying the gross characteristic of the lesion causing by the aortic obstruction. Non cardiovascular condition commonly associated with supravalvular aortic stenosis are mental retardation, facial anomalies, hypercalcemia, etc. The diagnosis can be established preoperatively by left heart catheterization and selective angiography. Recently, we experienced a case of multiple localized supravalvular aortic stenosis involving, just above the sinus Valsalva and just proximal of the innominate artery. The surgical correction which was performed by a vertical incision across the each narrowing of aorta with replacement of diamond shaped double velour Woven Dacron patch under the CPB. He was discharged without any event.

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Response Characteristics Of Steel Frame Structuresw With Added Elastic Dampers (탄성 댐퍼가 추가된 대형철골 구조물의 응답특성)

  • Bae, Chun-Hee;Cho, Cheul-Whan;Yang, Kyeong-Hyeon;Park, Young-Pil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.593-598
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    • 2002
  • Coupling adjacent steel frame using elastic dampers for control of response to low and moderate dynamic event is investigated in this paper. The complex modal superposition method is first used to determine dynamic characteristic, mainly modal damping ratio and modal frequency, of damper linked linear adjacent steel frame for fractical use. Dynamic response of steel frame linked by hydraulic-excitation method. This combined method can efectively and accurately determine dynamic response of non-clasically damped systems in the frequency domain. Parametric studties are finally performed to identify optimal parameters of elastic dampers for achieving the maximum modal damping ratio or the maximum response reduction of steel frame. It is demonstrated that using discrete elasatic dampers of proper parameters to link steel frame can reduce dynamic response significantly.

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Vibration based damage localization using MEMS on a suspension bridge model

  • Domaneschi, Marco;Limongelli, Maria Pina;Martinelli, Luca
    • Smart Structures and Systems
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    • v.12 no.6
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    • pp.679-694
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    • 2013
  • In this paper the application of the Interpolation Damage Detection Method to the numerical model of a suspension bridge instrumented with a network of Micro-Electro-Mechanical System sensors is presented. The method, which, in its present formulation, belongs to Level II damage identification method, can identify the presence and the location of damage from responses recorded on the structure before and after a seismic damaging event. The application of the method does not require knowledge of the modal properties of the structure nor a numerical model of it. Emphasis is placed herein on the influence of recorded signals noise on the reliability of the results given by the Interpolation Damage Detection Method. The response of a suspension bridge to seismic excitation is computed from a numerical model and artificially corrupted with random noise characteristic of two families of Micro-Electro-Mechanical System accelerometers. The reliability of the results is checked for different damage scenarios.

The optimum damper retrofit of cabinet structures by genetic (유전자알고리즘을 이용한 캐비닛 구조의 최적감쇠보강)

  • 이계희;최익창;하동호
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.10a
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    • pp.379-386
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    • 2004
  • The optimal seismic retrofitting of NPP(Nuclear Power Plant) cabinet structures that contained class 1 relays were studies in this paper. During earthquake event, the failure modes of relays are not appeared in form of structural failure, but are appeared in form of contact chatter of relay. Therefore, the retrofitting of cabinet has to be aimed to the reducing of the structural response, such as acceleration. In this study, the optimal characteristic values of dampers were searched by μ-GA (micro-Genetic Algorithm) scheme for several installation patterns. To keep accuracy and efficiency of analysis, the structural models of cabinet were considered as a frame structure. The responses of structure were obtained in form of acceleration response spectra derived from the results of nonlinear time history analysis including damping nonlinearity. The fitness function of the optimum procedure was constructed based on the ratio of maximum spectral value and target GERS (General Equipment Ruggedness Spectra). The results show the good improvements of fitness fur adequate retrofitting pattern. Especially, the improvements of fitness were remarkable when the damping exponents are proper.

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Design of Cavitation-Resistive Pump Inducer (공동현상을 고려한 펌프 인듀서 설계)

  • Jung, Keun-Hwa;Ahn, Kwang-Woon;Lee, Seungbae;Kim, Jin-Hwa;Kang, Shin-Hyoung
    • 유체기계공업학회:학술대회논문집
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    • 2001.11a
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    • pp.185-190
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    • 2001
  • The cavitation causes suction performance and efficiency of the high-speed pump to be reduced significantly To diminish these effects, the inducer has been used. Most of the inducer is designed at a maximum efficiency point of the pump, therefore suction performance drop due to effects of flow separation and inlet inverse flow is often observed at off-design point. The objective of this study is to find out the cavitation modes at various conditions by applying event detection technique and to design an inducer reducing cavitation. The pressure fluctuations at each cavitating condition were measured at inducer inlet and outlet locations using pressure transducers, which were located 90 degrees apart from each other to identify the cavitation modes. The time-frequency characteristics were analyzed by using Choi-williams distribution. In the second part of this paper, the inducer design method which uses nominal performance characteristic and onset condition of cavitation is introduced and applied to real situation.

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A Macro Parametric Data Representation far CAD Model Exchange using XML (CAD 모델 교환을 위한 매크로 파라메트릭 정보의 XML 표현)

  • 양정삼;한순흥;김병철;박찬국
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.12
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    • pp.2061-2071
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    • 2003
  • The macro-parametric approach, which is a method of CAD model exchange, has recently been proposed. CAD models can be exchanged in the form of a macro file, which is a sequence of modeling commands. As an event-driven commands set, the standard macro file can transfer design intents such as parameters, features and constraints. Moreover it is suitable for the network environment because the standard macro commands are open, explicit, and the data size is small. This paper introduces the concept of the macro-parametric method and proposes its representation using XML technology. Representing the macro-parametric data using XML allows managing vast amount of dynamic contents, Web-enabled distributed applications, and inherent characteristic of structure and validation.

Analysis on the Composite Laminated Plate Subjected to Low Velocity Impact (저속 충격을 받는 복합재료 적층판의 손상해석)

  • Lee, Ho-Chul;Lee, Young-Shin;Kim, Jae-Hoon;Jeon, Je-Choon
    • Proceedings of the KSME Conference
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    • 2000.11a
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    • pp.244-249
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    • 2000
  • Recently, composite material which has much excellent mechanical characteristics has been applied in many industries. However, it has a brittle characteristic under impact event. Especially, its invisible characteristics of the damaged area has been the motivation of many engineers investigation, and the nonlinearity of the impact mechanism is one of the main reason to assume the damaged area too simple. The damage mechanism of the composite laminated plate subjected to low velocity impact using ABAQUS/Standard & user subroutine was presented here.

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Fuzzy Syntactic Pattern Recognition Approach for Extracting and Classifying Flaw Patterns from and Eddy-Current Signal Waveform

  • Kang, Soon-Ju
    • Journal of Electrical Engineering and information Science
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    • v.2 no.4
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    • pp.59-65
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    • 1997
  • In this paper, a general fuzzy syntactic method for recognition of flaw patterns and for the measurement of flaw characteristic parameters for a non-destructive inspections signal, called eddy-current, is presented. Solutions are given to the subtasks of primitive pattern selection, signal to symbol transformation, pattern grammar formulation, and event-synchronous flaw pattern extraction based on the grammars. Fuzzy attribute grammars are used as the model for the pattern grammar because of their descriptive power in the face of uncertain constraints caused by nose or distortion in the signal waveform, due to their ability to handle syntactic as well as semantic information. This approach has been implemented and the performance of eh resultant system has been evaluated using a library of law patterns obtained from steam generator tubes in nuclear power plants by an eddy current-based non-destructive inspection method.

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