• Title/Summary/Keyword: slips

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Studies on Flowfields Around Axisymmetric Bodies in the Rarefied Gas Regime Using the Direct Simulation Monte Carlo Method (희박기체영역에서의 직접모사법에 의한 축대칭 형상 주위의 유동장 해석에 관한 연구)

  • Lee Dong-Dae;Park Hyeong-Gu
    • 한국전산유체공학회:학술대회논문집
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    • 1998.11a
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    • pp.71-77
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    • 1998
  • In this study we calculated the flowfields around the axisymmetric bodies in the rarefied gas regime by using the DSMC. A flat-ended cylinder was selected as a representative axisymmetric body and the gas used for all calculations was nitrogen. With zero angle of attack, an increasingly rapid rise in density and the effect of shock waves near the flat-ended face were examined. And on the cylinder surface velocity slips and boundary layers could be observed in the results. Larsen-Borgnakke model was used for the energy redistribution in inelastic collisions. And by considering all internal energy modes, the distributions of translational, rotational and vibrational temperatures were plotted. The calculations were peformed for various Knudsen numbers, Especially the rotational temperatures calculated for a case were compared with the experimental results. And the simulation results show good agreements with the experimental ones.

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A Study on the Domestic and International Safety Regulation for Slip, Trip and Fall Prevention (낙상사고 예방을 위한 국내·외 관련 규정 분석 연구)

  • Choi, Hyung Jin;Kim, Jung Soo
    • Journal of the Korea Safety Management & Science
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    • v.16 no.3
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    • pp.317-326
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    • 2014
  • Slips and falls are associated with many public injuries in Korea. It is also estimated that slipping are major contributors to slip, trip and fall injury burden. The primary purpose of the present study is to determine if, and to what extent, the standard could be improved in present environment. In order to fulfill our objective, the regulations in Korea and foreign countries were investigated and reviewed. Many kind of standard, mandatory documents and guideline were also reviewed. And then, regulations, standard, guideline etc. reviewed were compared with each others. Also, some criteria was developed in this study. Standard and criteria developed in this study will help to prevent slip, trip, and fall injuries.

Korean Amount Recognizer in Bank Slips (은행 전표에서 한글 금액 인식기의 구현)

  • 지태창;김은진;이일병
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10c
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    • pp.369-371
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    • 1998
  • 본 논문에서는 은행 전표의 한글 금액열을 인식하는 시스템을 제안한다. 한글의 낱자를 인식하는 연구가 활발히 진해되고 있는데 반하여, 본 연구에서는 한글의 낱자 인식 결과를 가지고 후처리를 한 후, 그 결과를 금액 숫자의 인식결과와 통합하는 시스템을 구성하였다. 한글 낱자 인식기는 MDC(Minimum Distance Classifier) 기법을 응용한 방법을 사용하였고, 그 후처리는 금액의 구조적인 특징을 사용하였다. 마지막으로 숫자 인식기의 결과와 상호 참조하여 인식기를 완성하였다. 인식 결과를 보면 한글 금액 문자열의 낱자에 대해서는 후처리를 하기 전에는 96.29%, 후처리를 한 후에는 97.72%의 인식률을 보였고, 한글 금액 문자열에 대해서는 후처리를 하기 전에는 79.96%, 후처리를 한 후에는 98.24%의 신뢰도를 보였다.

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Analysis of Herbal combination frequence on Clicical Herbal formulation (임상한의사 처방의 약물 배합 빈도 분석)

  • Cha, Woong-Seok;Lee, Tae-Hyung;Lee, Byung-Wook
    • Herbal Formula Science
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    • v.19 no.2
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    • pp.1-10
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    • 2011
  • Objectives : Since its enactment in 1987, the 56 standard prescriptions covered by insurance have remained unchanged from its original version. In this study, we tried to discover most frequently used herbal combinations by analyzing prescriptions used in actual clinical settings. Methods : We have built Structured Query Language to analyze herbal combination and progressed this analysis through analyzing the frequencies of medicinal herb combinations in medical prescription slips. Results : We have found out that traditional Korean medical doctors use about 13 herbs in a prescriptions and usually use 253 kinds of herb. And We have found out the most frequently used herbal combination. Conclusions : In this study, We can suggest new method to decide what do we need on insurance prescriptions.

Development of Correction Algorithm for Integrated Strapdown INS/GPS by using Kalman Filter

  • Lee, Sang-Jong;Naumenko, C.;Kim, Jong-Chul
    • International Journal of Aeronautical and Space Sciences
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    • v.2 no.1
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    • pp.55-66
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    • 2001
  • The Global Positioning System(GPS) and the Strapdown Inertial Navigation System(SDINS) techniques have been widely utilized in many applications. However each system has its own weak point when used in a stand-alone mode. SDINS suffers from fast error accumulation dependent on an operating time while GPS has problem of cycle slips and just provides low update rate. The best solution is to integrate the GPS and SDINS system and its integration allows compensation for each shortcomings. This paper, first, is to define and derive error equations of integrated SDINS/GPS system before it will be applied on a real hardware system with gyro, accelerometer and GPS receiver. Second, the accuracy, availability and performance of this mechanization are verified on the simulation study.

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Real- time Precise Positioning Algorithm with Float Ambiguity and Performance Analysis (실수 미지정수를 이용한 실시간 정밀위치 결정기법 및 성능분석)

  • 이영식;지규인;한훈택
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.51-51
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    • 2000
  • The ambiguity resolution is an essential task for the precise carrier phase differential GPS. In practice, however, there are still many problems in resolving the ambiguity in kinematic mode, especially in the urban areas. The multipath in received signal, the frequent change in visible satellites, and the cyclic slips make the ambiguity resolution very difficult task in real-time operation. In this paper, we consider a differential positioning with the float ambiguity that is free from the integer constraint. The float ambiguity estimation if carried out by the Kalman filter. The float and fixed ambiguities are combined together to determine the position in real-time kinematic mode.

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Combined burst synchronization/error detection systems maximizing bit slip correction ranges (최대 비트슬립 정정범위를 가지는 복합 버스트 동기/에러 검출 시스템)

  • 최양호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.7
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    • pp.1477-1486
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    • 1997
  • Conventioally the decoding methods and the design of coset codes for burst synchronization and error detection have been based on the concept that slips occuring to the right or to the left with respect to a reference timing are corrected. In this paper we newly approach to the design of coset codes relying on the condition that only a single code word can exists in an observation interval, which provides an extentended view on the conventional approach. A theorem concerning the condition is presented. A combined burst synchronization and error detection system with maximum slip correction capability have been devised based on the theorem and a detection method is falsely accepted in the presented of channel errors. The false acceptance probabilities of the system are derived and its performance is analyzed through computer computation using the derived results.

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A Study on the Plasticity Enhancement of Coal Fry Ash-Clay Bodies (석탄회-점토계 소지의 가소성 증진에 관한 연구)

  • 이기강;이효진;박천주;김동원;김유택;김석범
    • Journal of the Korean Ceramic Society
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    • v.33 no.2
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    • pp.135-142
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    • 1996
  • Fly Ashes which are produced from coal-fired powder plants and classified as general waste can be used as raw materials for bricks and tiles because of their compositional similarity with clays. There was a limit of substituting fly ash for clay because plasticity decreased with increasing fly ash additions. Accordingly this study tried to suggest a feastibility of enhancing the substitution ratio by controlling the interfacial properties of fly ash. The slip with 1:1 volume ratio showed that best dispersive characteristics under the condition of pH 2 Filter pressed cakes made of pH 2 slips also showed better plastickity than those of untreated ones. of pH 2 Filter pressed cakes made of pH 2 also shwoed better plasticity than those of untreated ones.

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Rheological Properties of Si3N4 Suspension and Microstructure of Slip Cast Si3N4 (Si3N4의 슬립물성과 Slip Cast Si3N4의 미세구조에 관한 연구)

  • 박정현;김진숙;박한수
    • Journal of the Korean Ceramic Society
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    • v.25 no.6
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    • pp.615-622
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    • 1988
  • To develope good slip and microstructure of Si3N4 the knowledge of the interaction of particles in liquid systems is required. In this work polyethyleneimines was tested as a stabilizer for Si3N4-water system. The stability of slip dispersed with polyethyleneimines was good over a wide range of pH and concentrated slips with low viscosity could be cast. This work comprises a systematic investigation including determination of electrical mobility in order to estimate the particle surface charge, determination of sedimentation rate, as well as measurements of the viscosity as a function of dispersants, pH and shear rates. The influence of deflocculation on the microstructure of slip cast Si3N4 was discussed.

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Industrial Accident Compensation Insurance Coverage and Industrial Accidents among Concrete Mixer Truck Drivers (콘크리트믹서트럭운전자의 산재보험 적용과 산업재해)

  • Kim, Min Ji;Choi, Eunsuk
    • Korean Journal of Occupational Health Nursing
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    • v.29 no.2
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    • pp.106-113
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    • 2020
  • Purpose: This study aimed to analyze industrial accident compensation insurance coverage and industrial accidents among concrete mixer truck drivers. Methods: Original data on industrial accidents from 2012 to 2017 were analyzed through descriptive statistics. Results: Industrial accident compensation insurance coverage was 44.6% in 2017. Most concrete mixer truck drivers were affiliated with small businesses. A total of 61 industrial accidents occurred in 2012, 65 in 2014, and 80 in 2017. The major types of industrial accident were falls, slips, and crushes. Conclusion: Because concrete mixer truck drivers are at high risk for industrial accidents, industrial accident compensation insurance coverage and industrial accident prevention should be strongly enforced.