• Title/Summary/Keyword: Space Experiment

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The Precision Validation of the Precise Baseline Determination for Satellite Formation

  • Choi, Jong-Yeoun;Lee, Sang-Jeong
    • Journal of Astronomy and Space Sciences
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    • v.28 no.1
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    • pp.63-70
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    • 2011
  • The needs for satellite formation flying are gradually increasing to perform the advanced space missions in remote sensing and observation of the space or Earth. Formation flying in low Earth orbit can perform the scientific missions that cannot be realized with a single spacecraft. One of the various techniques of satellite formation flying is the determination of the precise baselines between the satellites within the formation, which has to be in company with the precision validation. In this paper, the baseline of Gravity Recovery and Climate Experiment (GRACE) A and B was determined with the real global positioning system (GPS) measurements of GRACE satellites. And baseline precision was validated with the batch and sequential processing methods using K/Ka-band ranging system (KBR) biased range measurements. Because the proposed sequential method validate the baseline precision, removing the KBR bias with the epoch difference instead of its estimation, the validating data (KBR biased range) are independent of the data validated (GPS-baseline) and this method can be applied to the real-time precision validation. The result of sequential precision validation was 1.5~3.0 mm which is similar to the batch precision validation.

RESULTS OF THE TOTAL DOSE EXPERIMENT ON KITSAT-1 (우리별 1호에서의 총 방사선 측정 실험)

  • 이대희;신영훈;민경욱
    • Journal of Astronomy and Space Sciences
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    • v.14 no.1
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    • pp.80-86
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    • 1997
  • High energy particles in the earth's radiation belts cause transient and long term effects on electronic materials, devices, and integrated circuits on board the satellites. Hence, it is very important to have the information on the space radiation environment and the damage on the electronics caused by the se high energy particles. One of the radiation monitor devices frequently used in space is RADFET, a specially designed MOSFET with a thick gate oxide region. The present study focuses on the calibration of RADFET TOT500 using the $Co^{60}{\gamma}-ray$ source. The result shows that the response of RADFET is very sensitive to the change of temperature. The peculiar behavior observed in the TDE (Total Dose Experiment) on board the KITSAT-1 is identified as the thermal effect due to the change in the eclipse rate of the satellite.

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A Study on the Visual Interpretation of the Clothing Image as Clothing m Form and Dot Space Variation. (의복형태와 물방울무늬 공간변화에 따른 이미지의 시각적 평가)

  • 문삼련;이경희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.18 no.1
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    • pp.3-14
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    • 1994
  • This study is intended to identify the clothing mage as clothing form and dot space variation. This study consists of pre-experiment for setting the space between dot which shows the difference of the image and main experiment and also is made of factorial design for two variables-clothing form(H-line, A-line, V-line, X-line) dot (dot 1.0, dot 2.2, dot 3.4, dot 5.8) Qestionaire consists of 21 semantic differential scale expressing clothing form and .dot. Data is obtained from 50 female students maforing clothing and textile. The results of this study are as follows. 1) The image by the clothing form and the space dot variation is composed 5 factors' attention, activity, attraction, maturity, boldness. 2) The image by variation in clothing form dot has significant differences in attractive and attention factors, especially shows remarkable differences in attention. By choosing narrow space dot for attentive image, broden space dot for attractive image, you would be able to create the image you want. 3) The image by variation in dot clothing form has almost signific and differences in all factors, especially shows remarkable differences in activity. By choosing A-line for active image, V-line for mature and fashionable image, X-line for attractive, pretty and delicate mage, you would be able to create the image you want. 4) The interaction effect between clothing form and space dot was in attraction and maturity factor, V-line, X-line, dot 3.4 and dot 5.8 intensify attractive image, V-line and dot 1.0 mature image, X-line and dot 5.8 young image.

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Variations of SCN Space in Metabolic Acidosis and Alkalosis in Rabbits (대사성 산증 및 알칼리증에 있어서 SCN 공간의 변화)

  • Earm, Yung-E;Nam, Kee-Yong
    • The Korean Journal of Physiology
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    • v.5 no.2
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    • pp.41-44
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    • 1971
  • Thiocyanate space was determined in 23 bilaterally nephrectomized rabbits in acute metabolic acidosis and alkalosis. Acid-base disturbances were induced by the infusion of 0.3 N HCI or 0.3 N NaOH solution intravenously with the rate of 1 ml/min for 40 to 60 minutes. The blood pressure was monitored throughout the experiment and no changes in blood pressure was confirmed. The following results were obtained. 1. In the saline infused control rabbits, PH was 7.385 with negligible change in pH after the infusion, SCN space was 23.6% of body weight. 2. In the metabolic acidosis group, pH dropped from 7.417 to 7 130 and SCN space was 22.8% of body weight and suggested a negligible change in the extracellular space volume. 3. In the metabolic alkalosis group, pH increased from 7.393 to 7.478 and SCN space was 25.7% of body weight which confirmed a significant increase in the extracellular space volume.

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Design of a menu on a limited screen space (제한된 화면공간에서의 메뉴설계)

  • 곽지영;최재호;조항준;한성호
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1994.04a
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    • pp.93-102
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    • 1994
  • An experiment was conducted to provide guidelines for the design a menu on a limited screen space. Printers, facsimiles, copiers, etc. usually employ a small LCD, which provides either 8 or 16 characters to present functions and system status. Menu type, menu structure, and experience in menu structure were manipulated by using a within-subjects experimental design. The results imply that design recommendations for a menu on a limited screen space should be different from those for an ordinary CRT screen.

국제우주정거장 가압모듈 활용분야 및 전망 분석

  • 이주희;최기혁
    • Bulletin of the Korean Space Science Society
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    • 2004.04a
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    • pp.48-48
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    • 2004
  • 국제우주정거장 (International Space Station; ISS) 프로그램을 통하여 미국을 비롯한 15개 참여 국가들은 우주공간의 과학 연구 및 산업적 활용을 위한 전초기지를 만들어 나가고 있다. ISS에는 미세중력 (Microgravity) 환경을 이용하여 각종 실험을 수행하기 위한 공간으로 총 6개의 가압모듈 (Pressurized Module; PM)이 설치되었거나 설치될 예정이다. 현재 설치되어 있는 PM으로는 2001년 2월 ISS에 부착된 미국 NASA의 Destiny 실험모듈이 있으며, 향후 미국의 Centrifuge Accommodation Module (CAM), 일본의 Japanese Experiment Module- Pressurized Module (JEM-PM), 유럽연합의 Columbus Module, 러시아의 Research Module 등이 설치될 예정이다. (중략)

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A Study on the increase of space debris from Chinese Anti-Satellite and breach of the Outer Space Treaty (자국위성(自國衛星)의 파괴(破壞)에 따른 우주잔해의 증가와 우주조약위반(宇宙條約違反) 여부에 관한 소고(小考) - 중국의 자국위성파괴와 관련하여 -)

  • Kim, Sun-Ihee
    • The Korean Journal of Air & Space Law and Policy
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    • v.28 no.2
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    • pp.259-294
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    • 2013
  • After its experiment involving the exploding of a satellite in space in 2007, China proudly aired news on TV and ran articles in newspapers. However, the event was internationally criticized and drew widespread attention. Many countries denounced the explosion by pointing out that it could be part of the nation's plan to expand its military power to space or that it could pose a danger to the peaceful use of space. However, there is no talk of whether the experiment that produced a huge amount of space debris could have violated an international law, namely the Outer Space Treaty. Although space garbage has been said to be a serious problem, the amount is still on the increase. If we continue to launch new space launch vehicles into orbit at this rate, we will not be able to use it anytime soon like we do today. As the commercial use of space is likely to increase, the situation will certainly get worse. The international community is fully aware of the seriousness of the problem and working together to reduce the amount of space garbage. However, despite the fact that the United States and Soviet Union's ASAT(Anti-Satellite) programs have been implemented for a long time, there have been no complaints about them in terms of military expansion or breach of the Outer Space Treaty. Also, the recent Chinese test is largely viewed to be in accordance with international law. A lot of research has been undertaken with regard to the problem of space garbage. Now people's awareness of dangers being posed has been fully raised. Under the circumstances, the dismissing of China's satellite smashing, leaving a big mess in its wake, as nothing more than an experiment, is a red flag to, if not many, at least some people. By means of this thesis, I would like to review whether the Chinese test has violated an international space law. This thesis presents an overview of the issues surrounding the event and examines the possibility of violating the Outer Space Treaty, formally the Treaty on Principle Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies. After the China test, the UN Scientific and Technical Subcommittee first adopted space debris mitigation guidelines, I'll introduce the content of the guidelines and discuss the characteristics of the guidelines and what can be done to address the issue.

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Optimization of Sigmoid Activation Function Parameters using Genetic Algorithms and Pattern Recognition Analysis in Input Space of Two Spirals Problem (유전자알고리즘을 이용한 시그모이드 활성화 함수 파라미터의 최적화와 이중나선 문제의 입력공간 패턴인식 분석)

  • Lee, Sang-Wha
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.10-18
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    • 2010
  • This paper presents a optimization of sigmoid activation function parameter using genetic algorithms and pattern recognition analysis in input space of two spirals benchmark problem. To experiment, cascade correlation learning algorithm is used. In the first experiment, normal sigmoid activation function is used to analyze the pattern classification in input space of the two spirals problem. In the second experiment, sigmoid activation functions using different fixed values of the parameters are composed of 8 pools. In the third experiment, displacement of the sigmoid function to determine the value of the three parameters is obtained using genetic algorithms. The parameter values applied to the sigmoid activation functions for candidate neurons are used. To evaluate the performance of these algorithms, each step of the training input pattern classification shows the shape of the two spirals.

The Development of the Child's Conception of Space (유아(幼兒) 및 아동(兒童)의 공간개념(空間槪念) 발달(發達) - Piaget의 연구(硏究)를 중심(中心)으로 -)

  • Kim, Hang Ja
    • Korean Journal of Child Studies
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    • v.3
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    • pp.35-48
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    • 1982
  • The purpose of this study is to investigate the Piaget's theory of the child's conception of space, which explains the stage of child's congnitive development. This thesis consists of 4 Chapters, including introduction, which examines the concept of space perception, and the development of arithmetic conception, and suggests the outline of this study. In the Chapter II, the brief history of topological Psychology, and the current situation of this theory has been explained. According to Piaget's theory of the conception of space, the child's development of the conception of space develops orderly three stages, that is to say, the stage of conception of space by the topological relations, the stage of projective conception of space, and finally the stage of the Euclidian, conception of space. Children's development of the conception of space continuously, and orderly has been made by these stages. Also, in this Chapter, Piaget's experiment about the development of child's conception of space has been explained. In the Chapter III, the children's conception of geometry has been examined. Here explains the development of space representation, and of seriation or classification. In the Chapter IV, some theories of the conception of space has been examined, and some points of view has been made as a conclusion.

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A Study on the Acoustic Characteristics Proposal of Won Buddhist Sanctums by Psychoacoustics Experiment (청감실험을 통한 원불교 대법당의 음향특성 제안에 관한 연구)

  • Han, Kyeong-Yeon;Seo, Jung-Seok;Kim, Jae-Soo
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2003.11a
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    • pp.59-65
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    • 2003
  • The present article has the purpose of evaluating subjective response of Won Buddhism sanctums by psychoacoustics experiment. Furthermore, basing on this experiment, the present article makes a suggestion of a physical sound-evaluating index. To achieve the purpose, I conducted an psychoacoustics experiment at 6 sanctuaries out of the representing 40 sanctuaries of Won Buddhism sanctums, which size is bigger than 1,000 m$^3$. I made a reanalysis with 3 Buddhist sanctums out of the subjects of psychoacoustics experiment which are generally rated superior. From the result, I can make each evaluation type into two types, sound clarity and space sense of sound. Also, I make various suggestions of physical parameter, with which I can evaluate the proper sound condition for Won Buddhism sanctums.

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