• Title/Summary/Keyword: Burn-back Analysis

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The LAE Burn Strategy Planning for Geostationary Satellite (정지궤도 위성의 LAE Burn Strategy Planning)

  • Kim, Bang-Yeop;Lee, Ho-Hyoung
    • Aerospace Engineering and Technology
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    • v.6 no.2
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    • pp.96-103
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    • 2007
  • A program for LAE (liquid Apogee Engine) firing strategy calculation was developed. This program can be used as the first stage of transfer orbit analysis, which process receives input parameters as like initial orbit elements, ground TT&C stations positions, satellite performances and makes firing user-selectable strategies. The developed program is dedicated to GEO satellites which using LAE generally and it can calculate six back-up strategies and deals situation its maximum firing number is six. The MS-EXCEL software was used for the input and output process. And the numerical calculation part was embodied with MATLAB functions.

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Study of Hybrid Optimization Technique for Grain Optimum Design

  • Oh, Seok-Hwan;Kim, Yong-Chan;Cha, Seung-Won;Roh, Tae-Seong
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.4
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    • pp.780-787
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    • 2017
  • The propellant grain configuration is a design variable that determines the shape and performance of a solid rocket motor. Grain configuration variables have complicated effects on the motor performance; so the global optimization problem has to be solved in order to design the configuration variables. The grain performance has been analyzed by means of the grain burn-back and internal ballistic analysis, and the optimization technique searches for the configuration variables that satisfy the requirements. The deterministic and stochastic optimization techniques have been applied for the grain optimization, but the results are imperfect. In this study, the optimization design of the configuration variables has been performed using the hybrid optimization technique, which combines those two techniques. As a result, the hybrid optimization technique has proved to be efficient for the grain optimization design.

Content Analysis of Wormwood Smoke(Ssukjahun) Experiences in Women (여성의 쑥좌훈 경험에 대한 내용분석)

  • Lee, Kwang-Ok;Jang, Sun-Bok;Yoo, Ji-Soo
    • Journal of East-West Nursing Research
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    • v.14 no.1
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    • pp.68-77
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    • 2008
  • Purpose: This Study aims to explore the Wormwood smoke(Ssukjahun) experiences of women and to provide the data to develop Korean traditional nursing intervention for women. Methods: A sample of 15 women aged between 20 to 60 years with Ssukjahun experiences was interviewed and content analysis was used to analyze the data. Results: Six categories and Thirty attributes were derived for Ssukjahun experiences in women. The reason of Ssukjahun is related to illness included vaginitis, insomnia, mental depression, circulation down of hand and feet, repeat abortion, dysmenorrhea, hemorrhoids, disc, rheumatism, and asthma. The place of Ssukjahun was home, oriental hospital and Ssukjahun room. Also method of Ssukjahun included steam methods and burn the wormwood. The time-consuming of Ssukjahun was about 30 minutes. The response and effect in Ssukjahunincluded relax, decreasing rhinitis, weight reduction, feel better, increasing circulation, sleep well, reducing constipation, insomnia, hemorrhoid, back pain, asthma, and dysmenorrhea. The negative effect of Ssukjahun included vesicle, headache, itching sense, generalache, acne, and edema. However, women who did Ssukjahun believed that is the belligerent reaction because it is gone after several times. The preference of Ssukjahun than hospital treatment is related to side effect of medication, temporary method for reducing symptom. Recommends: It is recommended for nurses to understand experience of Ssukjahun in women. If Ssukjahun is to be own nursing intervention, it has to find solutions to encourage positive experiences and overcome negative experiences. Also it recommended research for experience of men.

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A Study on the Steady-State Characteristics of Symmetric Pintle Nozzle with Varying Position of Pintle and Change in Altitude (대칭형 핀틀 노즐의 핀틀 위치와 고도 변화에 대한 정상상태 특성 연구)

  • Jeong, Kiyeon;Kang, Dong-Gi;Jung, Eunhee;Lee, Daeyeon;Choi, JaeSung
    • Journal of the Korean Society of Propulsion Engineers
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    • v.23 no.1
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    • pp.33-45
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    • 2019
  • In this study, numerical simulations were performed to investigate the steady-state characteristics of a symmetric pintle nozzle by varying the position of the pintle and the altitude. The pintle nozzle shape was used in a linear pintle nozzle that had been analyzed prior to the study, and the boundary conditions of the chamber were considered to be according to the propellant burn-back characteristics. A software was used to perform a verification analysis of the square nozzle, pintle nozzle, and high-altitude conditions with an appropriate analytical technique. The pintle position had three different nozzle throat area conditions-: fully closed, half open, and fully open, and the altitude was set at 0, 5, and 20 km. The study compared the thrust, pintle drive load, and static stability at each condition.

Survey on Personal Medicines in Cheju Island (제주도 민간요법에 관한 조사연구)

  • Lee, Kyung-Hee
    • Journal of East-West Nursing Research
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    • v.2 no.1
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    • pp.37-53
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    • 1997
  • The purpose is to inspect the personal medicines in Cheju island that are used traditionally and to get their characteristics. The subjectives are 39 Cheju people, men 10, women 29, who were horned, grown up in Cheju and agreed with this study. The ranges of age are 10 persons(m : 1, w: 9) over 40 less 50 years old, 14(m : 7, w : 7) over 50 less 60, 5(m : 1, w : 4) over 60 less 70, 6(m : 0, w : 6) over 70 less 80, and 4(m : 1, w : 3) over 80. The average age is 64.5 years old. The method to collect the data is 20 structured opening questionaires that are based on references. The duration to collect datas is 11days from 4th, Aprill 1997 to 14th, Aprill 1997. The workers who are trainned the interview methods went their villages and got answers after explaining the purpose and contents to them. Somtimes they used to record the answers. The analysis was identified the subjectives to four regions of Cheju, arranged answers with items, rearranged the same answers, counted with number and percentage. And classified the materials and characteristics. The results of this study are followed: The things that is used as personal medicines are the effects through experiences ans misteries that have hand down by word of mouth, even though they are not scientific. People used the materials arround their circumference. It is an accumulation of experiences. The ways used in eating, doing acupuncture or sting, exposing to smoke, wheedling, fixing after pounding. Almost materials are plants. Mugwort is effective in fever, gastritis, hemorrhoid, diarrhea, edematous hands or feet and dermatitis. Citron and Arrowroot in fever, gastritis. Seeds of Pumpkin in indigestive, hemorrhoid, edematous hands or feet. Gallic in fever, diarrhea, frostbite, dermatitis, and toothache. Motherwort in diarrhea, gastritis. Radish juice in indigestive, jaundice. Bean paste in burn, wound. Acupuncture in fever, gastritis, indigestive, back pain, edematous hands or feet. Sting as similar with it in fever, indigestive, edematous hands or feet. Cigarrette in hemorrhoid, wound, toothache. Cowstools in edematous hands or feet, wound. Sault is usded a lot in fever, gastritis, indigestive, hemorrhoid, uneffective voiding, edematous hands or feet, dermatitis, having a boil around the mouth, toothache, and eye disease. Japanese Parsley in fever, gastritis. Egg Apple in diarrhea, edematous hands or feet, frostbite. And Wild Chrysanthemum is effective in jaundice. In the conclusion, people used the things arround. A things is effective in several symptoms. If these are not effective, they would used the magic as god's anger. As locally, they used the grasses and fruits in the middle of Mt. Halla and seafood on the sea village.

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