• Title/Summary/Keyword: Great Point

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Thermo-Mechanical Analysis of Continuous-Adjustment Thruster using Explosion Pressure (폭압을 사용하는 연속조정 추진구조체의 열-구조해석)

  • Kim, Kyung-Sik;Kwon, Young-Doo;Kwon, Soon-Bum;Gil, Hyuck-Moon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.24 no.6
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    • pp.699-705
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    • 2011
  • High-maneuver missile is a projectile which demands a strong momentum at short time. To produce a necessary thrust for the flight, the gas of high temperature and pressure is generated through explosive combustion of solid propellant, and a great thrust can be obtained by expanding this high temperature and pressure gas. Although the operating time of a rocket motor is less than a few seconds, a failure of part or ablation near the throat of nozzle may take place during the expansion of high temperature and pressure gas for great thrust. In other words, for the precise control of a missile an exact stress analysis considering both, the thermal stress caused by the heat transfer between combustion gas and wall, and the mechanical stress caused by the pressure change in the flow, should be considered first. In this connection, this study investigated the safety, as a point of view of stress and melting point of the material, of the pre-designed thrust generating structure which is subjected to high temperature and pressure as a function of motor operating time.

Synthetic Conception of Ten Heavenly Stems and Twelve Earthly Branches According to Mathematical Principle (수리(數理)를 통해 살펴본 십간(十干)과 십이지(十二支)의 종합적 개념)

  • Han, Gook;Yun, Chang-Yeol
    • Journal of Korean Medical classics
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    • v.33 no.1
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    • pp.29-50
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    • 2020
  • Objectives : Objectiveness and accuracy of numbers could allow for a new way of understanding the principle of Ten Heavenly Stems(THS) and Twelve Earthly Branches(TEB) when applied. Methods : The order of the THS and TEB, the Five phases of direction and change, conversion of other, conversion of self of the Stems and Branches were examined through numbers. Results & Conclusions : The numerical combination of the Stems and Branches depends on the identification of the Three Points. Conversion of self of the Heavenly Stems are as follows: for 甲 3+5=8, for 乙 8+4=12, for 丙 7+1=8, for 丁 2+8=10, for 戊 5+7=12, for 己 10+10=20, for 庚 9+9=18, for 辛 4+6=10, for 壬 1+3=4, for 癸 6+2=8. Conversion of self of the Earthly Branches are as follows: for 子 1+2=3, for 丑 5+5=10, for 寅 3+2=5, for 卯 8+4=12, for 辰 5+1=6, for 巳 2+8=10, for 午 7+7=14, for 未 10+10=20, for 申 9+7=16, for 酉 4+9=13, for 戌 5+6=11, for 亥 6+3=9. Here the Stems and Branches could be understood intensively. Among the Stems and Branches, the Great Points are 壬, 癸, 戌, 亥, 子, Emperor Points are 甲, 戊, 丑, 午, and Empty Points are 己, 未.

A Study on Shifting of Pivoting Point in accordance with Configuration of Ships (선형에 따른 전심의 이동에 관한 연구)

  • 최명식
    • Journal of the Korean Institute of Navigation
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    • v.10 no.2
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    • pp.83-96
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    • 1986
  • In the restricted sea way such as fair way in harbor, narrow channel etc, the safe ship-handling is a very important problem, which is greatly related with turning ability of ships. It is of great importance that ship-handlers can grasp the position of pivoting point varying with time increase at any moment for relevant steering activities. Mean while, in advanced ship-building countries they study and investigated pivoting point related with turning characteristics, hut their main interest lies in ship design, not in safe ship controlling and maneuvering. In this regards it is the purpose of this paper to provide ship-handlers better under standing of pivoting point location together with turning characteristics and then to help them in safe ship-handling by presenting fact that pivoting points vary according to configuration of ships. The author calculated the variation of pivoting point as per time increase for various type of vessels, based on the hydrodynamic derivatives obtained at test of Davidson Laboratory of Stevens Institutes of Technology , New Jersey, U.S.A. The results were classified and investigated according to the magnitude of block coefficient , length-beam ratio, length-draft ratio, rudder area ratio ete, and undermentioned results were obtained. (1) The trajectory of pivoting point due to variation of rudder angle are all the same at any time, though the magenitude of turning circle are changed variously. (2) The moving of pivoting point is affected by the magnitude of block coefficient, length-beam ratio, length-draft ratio, however the effect by rudder area ratio might be disregarded. (3) In controlling and maneuvering of vessels in harbor, ship-handlers might regard that the pivoting point would be placed on 0.2~0.3L forward from center of gravity at initial stage. (4) The pivoting point of VLCC or container feeder vessels which have block coefficient more than 0.8 and length-beam ratio less than 6.5 are located on or over bow in the steady turning. (5) When a vessel intends to avoid some floating obstruction such as buoy forward around her eourse, the ship-handler might consider that the pivoting point would be close by bow in ballast condition and cloase by center of gravity in full-loaded condition.

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The study on necessity of equipment ship phone and improvement of concerning laws in small ships (소형 선박의 SHIP PHONE 설치 필요성 및 관계 법규 개선에 관한 연구)

  • 신현식
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.1 no.1
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    • pp.13-20
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    • 1997
  • Tens of domestic maritime accidents that happen in around 5 toned small ships cause great loss of lives every year. Ship phones in small ships, the communication equipment usable in accidents, can remove factors that cause great loss of lives and properties. Thus we studied on the ship phones on a national point of view to reduce loss that caused by maritime accidents.

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A Model Feasibility Analysis of Commerce Building (상업건축물의 사업타당성 분석 모형 구축)

  • Kook, Dong-Hoon;Son, Ki-Young;Kim, Sun-Kuk
    • KIEAE Journal
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    • v.7 no.3
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    • pp.71-79
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    • 2007
  • The starting point of successful building production process is the feasibility study of the project. If the feasibility study is poor which is affected in direct production processes such as designing and engineering, it incurs a great unrecoverable loss to the company. The government institutionalized the feasibility study for projects that budgets over 50billion won in an effort to ensure competitiveness of the construction industry after IMF; however, the system and effort to created systematic studies or guidance preparation for private construction development projects are lacking in great deal. Therefore, the objective of this study is to establish the analysis factors of feasibility study and evaluation standard by systematic analysis in consideration of the changes of various variables and mutual relationships using system dynamics technique for office buildings among commercial buildings.

A Study on the Environmental Improvement in the Interior Construction Fields with the check-list (실내건축의 작업환경 개선을 위한 기본적 관리방안에 관한 연구)

  • 이용의
    • Korean Institute of Interior Design Journal
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    • no.9
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    • pp.10-17
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    • 1996
  • With the ever-increasing important of high-speed information in society as we move towards the 21 st century. Interior design and it's working condition has been changed a great deal included a sort of each special character and make a difference against the others. It used to be find a great poles asunder of worker's safety and project quality according to the environmental dimension of interior construction field as if they should be a pleasantness or poor condition. This research aimed to improvement of environmental construction field of interior with construction engineers and particular interior labors in 4 phases as : ⅠThe preparatory phase : -Secure a Budget, Environmental safety supervisor -Fix of Design quality, Construction period. -Choice of Construction method, Sub constructing Ⅱ. Starting work phase ; -Capacity , Safety of temporary power line. -Carriage, Stock of Material -Safety of Electronic tools, -Personal protector. Ⅲ. Working period ; -Ventilation, I illumination of working place. -Measurement of environmental working condition Ⅳ.Finish working phase ; -Analysis of measurement data. -Evaluation and making up for the weak point. -Keeping data.

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Potential Profiles and Capacitances of an Ideally Polarizable Electrode/Hard Sphere Electrolyte System

  • Kim, Sang-Youl;Vedam, K.
    • Bulletin of the Korean Chemical Society
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    • v.11 no.6
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    • pp.487-493
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    • 1990
  • A complete potential profile of an electrical double layer is calculated from a distribution function of charged particles based upon a model where the effect of a charged electrode and the finite size of ion are explicitly included. Electrons which are distributed on the electrode surface are assumed not to penetrate the electrode/electrolyte boundary. Formation of the constant density regions and their effects on potential and the electrical double layer capacitances are studied in great detail. The distribution of surface electrons as well as the constant density regions are found to be essential in characterizing the electrical double layer. The introduction of the ion size into the prior electrical double layer model of an ideally polarizable electrode/point charged electrolyte system, shows a great improvement in its characteristics mostly at negative potential region.

Efficient Digitizing in Reverse Engineering By Sensor Fusion (역공학에서 센서융합에 의한 효율적인 데이터 획득)

  • Park, Young-Kun;Ko, Tae-Jo;Kim, Hrr-Sool
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.9
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    • pp.61-70
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    • 2001
  • This paper introduces a new digitization method with sensor fusion for shape measurement in reverse engineering. Digitization can be classified into contact and non-contact type according to the measurement devices. Important thing in digitization is speed and accuracy. The former is excellent in speed and the latter is good for accuracy. Sensor fusion in digitization intends to incorporate the merits of both types so that the system can be automatized. Firstly, non-contact sensor with vision system acquires coarse 3D point data rapidly. This process is needed to identify and loco]ice the object located at unknown position on the table. Secondly, accurate 3D point data can be automatically obtained using scanning probe based on the previously measured coarse 3D point data. In the research, a great number of measuring points of equi-distance were instructed along the line acquired by the vision system. Finally, the digitized 3D point data are approximated to the rational B-spline surface equation, and the free-formed surface information can be transferred to a commercial CAD/CAM system via IGES translation in order to machine the modeled geometric shape.

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Watershed Management Measures for Water Quality Conservation of the Hwaseong Reservoir using BASINS/HSPF Model (BASINS/HSPF 모델을 이용한 화성호 수질보전을 위한 상류 유역 수질개선방안 연구)

  • Kang, Hyeongsik;Jang, Jae Ho
    • Journal of Korean Society on Water Environment
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    • v.29 no.1
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    • pp.36-44
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    • 2013
  • HSPF model based on BASINS was applied to analyze effects of watershed management measures for water quality conservation in the Hwaseong Reservoir watershed. The model was calibrated against the field measurements of meteorological data, streamflow and water qualities ($BOD_5$, T-N, T-P) at each observatory for 4 years (2007-2010). The water quality characteristics of inflow streams were evaluated. The 4 scenarios for the water quality improvement were applied to inflow streams and critical area from water pollution based on previous researches. The reduction efficiency of point and non-point sources in inflow streams was evaluated with each scenario. The results demonstrate that the expansion of advanced treatment system within wastewater treatment plants (WWTPs) and construction of pond-wetlands would be great effective management measures. In order to satisfactory the target water quality of reservoir, the measures which can control both point source and non-point source pollutants should be implemented in the watershed.

Study on Ego states in the view of Transactional analysis, Coping style and Health states of Nursing Students (상호교류분석으로 본 간호학생의 자아상태와 스트레스 대처방법 및 건강상태에 관한 연구)

  • Won, Jeong-Sook;Kim, Jeong-Hwa
    • Journal of East-West Nursing Research
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    • v.7 no.1
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    • pp.68-81
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    • 2002
  • The purpose of this study is to analyze the type of ego states and stress coping style on female college students who are in the course of nursing study. This study is performed in the view of Transactional Analysis and designed to scrutinize descriptive correlations between the type of ego states and stress coping style. The subject is consists of 144 freshmen and sophomore, 138 junior and senior students group, who are students of K nursing college located in Seoul. The sampling investigation period is on Sept. 14, 2002 to Oct. 26, 2002. The measuring instrument used for Transactional Analysis ego state is 50 items Ego-gram research paper devised by Dusay(1997). For studying coping style, Folkman & Lazarus's measurement(1984) was adopted, which is translated and modified by Han, and Oh,(1990). Health states is adopted by standardized health inspecting instrumental table (Cornell Medical Index:CMI) which is designed for Korean people by Ko and Park(1980) Statistic average and standard deviation were generated by using SPSS PC+, t=test and Pearson correlation. The results were as follows: 1) In the type of ego states on both groups indicated the arithmetic apex NP(maximum value), then the point A was high and the data made a down slope to point AC. In the comparison to type of ego states between two groups, only at point CP, the data value of upper year students represented higher than that of lower year ones by c(t=2.28, p=.023). 2) Stress coping style of whole students were highly and affirmatively dedicated to research. Especially hopeful aspect(t=.67, p=.05), relaxation of tension(t=-2.16, p=.03) made significant difference each other in the view of arithmetic calculation. 3) In view of nursing students' physical health states, there is significant difference in past history(t=2.50, p=.013) and in case of mental health states, there are considerable discrepancies between lower group(73.52) and upper group(75.11)(p<.05). In view of all field, state of tension(t=2.13, p=.048) has difference. 4) While verifying coping style in terms of ego states level between lower and upper students group, In type CP, high level ego states group indicated significant difference on stress coping style area than low leveled group and made such sequences as the central point of problem, In type NP, sequences such as the central point of problem, In type A, the central point of problem, In type FC, hopeful aspect and In type AC, hopeful aspect and indifference were derived significantly different (p<.05). 5) While verifying health state differences in the level of lower and upper ego states, In type FC, low level group(150.29) marked higher point than upper group(145.19), there is remarkable discrepancy and so did whole health state(p=.014), In type AC both mental state(p=.000) and whole health state (p=.015) showed differences. 6) When analyzing correlations between whole students' ego states, copying style and health state, all type of ego state showed differences(p<.001). In correlations between ego state and health state, in type FC physical state had an apex and there are inverse correlations among the other types. Especially, type FC showed inverse correlations with great discrepancies(p<.05). In mental state, type NP(${\gamma}=.198$, p<.001) and type A(${\gamma}=.166$, p<.05) represented straight correlations with remarkable differences. Especially, In type AC showed inverse correlations(${\gamma}=.282$, p<.001). In case of correlations between copying style and health state, indifference(${\gamma}=-.157$) and relaxation of tension(${\gamma}=-.158$) presented great difference(p<.05). In mental state, central point of problem and search for social support showed straight correlations with great discrepancies(p<.05), hopeful aspect and indifference showed inverse correlations with considerable differences(p<.001).

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