• Title/Summary/Keyword: moon

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Design of Orbit Simulation Tool for Lunar Navigation Satellite System

  • Hojoon Jeong;Jaeuk Park;Junwon Song;Minjae Kang;Changdon Kee
    • Journal of Positioning, Navigation, and Timing
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    • v.12 no.4
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    • pp.335-342
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    • 2023
  • Lunar Navigation Satellite System refers to a constellation of satellite providing PNT services on the moon. LNSS consists of main satellite and navigation satellites. Navigation satellites orbiting around the moon and a main satellite moves the area between the moon and the L2 point. The navigation satellite performs the same role as the Earth's GNSS satellite, and the main satellite communicates with the Earth for time synchronization. Due to the effect of the non-uniform shape of the moon, it is necessary to focus on the influence of the lunar gravitational field when designing the orbit simulation for navigation satellite. Since the main satellite is farther away from the moon than the navigation satellite, both the earth's gravity and the moon's gravity must be considered simultaneously when designing the orbit simulation for main satellite. Therefore, the main satellite orbit simulation must be designed through the three-body problem between the Earth, the moon, and the main satellite. In this paper, the orbit simulation tool for main satellite and navigation satellite required for LNSS was designed. The orbit simulation considers the environment characteristics of the moon. As a result of comparing long-term data (180 days) with the commercial program GMAT, it was confirmed that there was an error of about 1 m.

Diagnostic Accuracy of Clinical Test for Anterior Cruciate Ligament Injury: Systematic Review

  • Deniz Yasemin;Sang-Woo Pyun;HyungSu Lee;Seong-Eun Kim;SunGyu Han;Dongyeop Lee;Ji-Heon Hong;Jae-Ho Yu;Jin-Seop Kim;Seong-gil Kim
    • The Journal of Korean Physical Therapy
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    • v.35 no.3
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    • pp.57-63
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    • 2023
  • Purpose: The aim of this study was to conduct a systematic review of randomized controlled studies from 2012 to present that explore the diagnostic accuracy of clinical tests used for diagnosing anterior cruciate ligament (ACL) injury. Methods: Study design: Systematic review. Literature search of the PubMed and Scholar databases was conducted using keywords related to diagnostic accuracy of clinical tests for ACL injury. The PRISMA Guidelines were followed to conduct this study. The Cochrane Risk of Bias Tool was utilized to assess the quality of each included study. Results: As a result, 8 studies were included, and 6 clinical tests used in ACL tears were evaluated for diagnostic accuracy. The pivot shift test was reported as having the highest +LR (29.5) value with a sensitivity of 59% and a specificity of 98%. However, the test with the lowest -LR value was the lever test, and the values were as follows: -LR (0.08), +LR (4.7), specificity (80%), sensitivity (94%). Conclusion: In this study, it was concluded that a single clinical test is not sufficient to determine the presence of ACL injury. Test combinations have a higher diagnostic accuracy than a single test. In this study, the accuracy of the clinical tests was examined without considering the amount of ACL rupture and acute-chronic condition. Further research is required to examine the impact of these two factors on diagnostic accuracy of clinical test.

The Types of Secondary School Students' Preconceptions on the Motion of the Earth and the Moon (계통도를 이용한 중.고등학생의 지구와 달의 운동에 관한 개념 유형 연구)

  • Woo, Jong-Ok;Lee, Hang-Ro;Min, Jun-Gyu
    • Journal of The Korean Association For Science Education
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    • v.15 no.4
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    • pp.379-393
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    • 1995
  • In spite of school science learning, the students' conceptions have not been changed easily. Therefore, to make students overcome their non scientific conceptions has been an important issue in science education. The purpose of this study was to identify the conceptions of students and teachers on the motion of the earth and the moon. The instrument was developed for estimating students' understandings of the concepts related to the motion of the earth and the moon. The validity of the instrument was examined by the specialists in Science Educator and Astronomer. At the same time, the two field trials had been executed, and the items were modified. Also, it consists of 12 items including 9 two-tier multiple choice items and 3 multiple choice items. The population of this study consists of 250 eighth-, 299 tenth-, 292 eleventh-grade students, 134 science teachers in secondary school. SPSS/PC+ was adopted for the statistical analysis. The type of misconceptions possessed students were as follows: 1) At 12:00 noon, the sun is directly overhead. 2) First quarter moon is a half of overall surface of the moon. 3) Air don't rotate with the earth surface because it keeps apart from the earth surface. 4) Summer is warmer than winter, because the earth is nearer from the sun in summer. 5) Whenever season is changed, the direction of rotation axis of the earth is changed. 6) The moon is the brightest at the position of new moon, because the distance between the moon and the sun is the shortest and the moon is received strongest sunlight. 7) The moon is not seen at the position of real full moon, because it is covered with shadow of the earth. 8) When the moon is not seen in the earth, sunlight is not reached at the moon. The major findings were as follows : 1) The middle school students had more misconceptions than those of high school students. And female students had more misconceptions than those of male ones. 2) The rate of correct answer and the type of conception in the tenth grade students were very similar with eleventh grade students. 3) The higher cognitive level, the better development of scientific conception and the less misconception. Also, the correlation coefficient between scientific conception score and GALT score was 0.57. 4) The students in scientific part had higher the rate of correct answer than those of students in human part and the former had less misconception than the latter. 5) The rate of correct answer about model and figure items was lower than descriptive ones, because they did not understand about figures itselves. These types of misconceptions will be used for science instruction and studies of other conceptions need.

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Identification of 2-Deoxy-scyllo-inosose Synthase in Aminoglycoside Producer Streptomyces

  • Kharel, Madan-Kumar;Subba, Bimala;Lee, Hei-Chan;Liou, Kwang-Kyoung;Woo, Jin-Suk;Kim, Dong-Hwan;Moon, Young-Ho;Sohng, Jae-Kyung
    • Journal of Microbiology and Biotechnology
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    • v.13 no.5
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    • pp.828-831
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    • 2003
  • Although most of the DOS containing aminoglycosides are produced by Streptomyces, very little information is available about their biosynthesis. In the present paper, we report a method to isolate DOI synthase, a key enzyme in the biosynthesis of DOS, from aminoglycoside producer Streptomyces. PCR primers based on conserved region of DOI synthases were specific and reliable for the isolation of the biosynthetic genes of DOS containing aminoglycosides or the screening of the aminoglycoside producers. The use of DOI synthase as a probe could save both time and cost of cloning aminoglycoside biosynthetic genes.

A case of Laurence Moon-Bardet Biedl Syndrome with Chronic Renal Failure (만성 신부전을 동반한 Laurence Moon-Bardet Biedl 증후군 1례)

  • Park Lae Kyong;Lee Dong Hwan;Moon Chul;Kim Eun Mi
    • Childhood Kidney Diseases
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    • v.2 no.2
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    • pp.200-203
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    • 1998
  • The Laurence Moon-Bardet Biedl syndrome is characterized by obesity, mental retardation, visual impairment with retinitis pigmentosa, polydactyly, hypogonadism and renal manifestations. We experienced an 11 years old female with Laurence Moon-Baret Biedl syndrome associated chronic renal failure. She was diagnosed to have LMB syndrom according to the clinical manifestations of polydactyly on hands and feet, mental retardation, obesity, retinitis pigmentosa and chronic renal failure. She is on maintenance hemodialysis now.

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Ultra High-speed 3-dimensional Profilometry Using a Laser Grating Projection System

  • Park, Yoon-Chang;Ahn, Seong-Joon;Kang, Moon-Ho;Kwon, Young-Chul;Ahn, Seung-Joon
    • Journal of the Optical Society of Korea
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    • v.13 no.4
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    • pp.464-467
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    • 2009
  • The grating projection method with phase-shifting technique is very useful in measuring the 3-dimensional (3D) shape with high accuracy and speed. In this work, we have developed an ultra high-speed digital laser grating projection system using a high-power laser diode and a highsensitivity CMOS camera. With our system, the optical measurement required to find out the profile of a 3D object could be carried out within 2.6 ms, which is a significant ($\sim$10 times) improvement compared with those of the previous studies.

Motioncapture program development by using Kinect (Kinect를 이용한 모션캡쳐 프로그램 개발)

  • Kim, Seul-Gi;Kim, Min-Jae;Park, Gi-Hyun;Lee, Yu-Yong;Heo, Woong;Kim, Jong-Hee
    • Annual Conference of KIPS
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    • 2012.11a
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    • pp.492-494
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    • 2012
  • 본 논문에서는 Kinect 장비를 이용하여 모션캡쳐를 할 수 있는 툴을 제작하여 제공한다. 자신이 캡쳐한 모션 데이터를 Web상에 공유하여 다른 사용자들이 볼 수 있게 한다. 궁극적인 목표로는 보급형 모션캡쳐장비 Kinect 사용한다면 간단하고 비교적 저렴하게 모션캡쳐를 사용할 수 있을 것이며, 모션캡쳐라는 생소함을 해소시키고자 함에 목표를 두었다.

SEARCH FOR RADIO TECHNOSIGNATURE FROM THE FARSIDE OF THE MOON (달 뒷면의 전파망원경을 이용한 기술문명징후 탐색)

  • Minsun Kim;Sungwook E. Hong;Taehyun Jung;Hyunwoo Kang;Min-Su Shin;Bong Won Sohn
    • Publications of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.59-73
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    • 2023
  • Since the farside of the moon is a place to avoid artificial radio frequency interference (RFI) created by human civilization, it is a most suitable place for searching technosignature, which are signs of technological civilization in the universe, in the radio band. The RFI is a factor that makes the study of searching technosignature quite complicated because it is difficult to distinguish between technological signals produced by human and extraterrestrial civilizations. In this paper, we review why the farside of the moon is the best place to detect technosignature and also introduce radio observatories on the farside of the moon that have been proposed in radio astronomy. The SETI (Search for Extraterrestrial Intelligence) project on the farside of the moon is expected to be one of the main candidates for international collaboration research topics on lunar surface observatory.

The Attendance Management System Using The Embedded terminal for Facial Recognition (얼굴 인식용 임베디드 단말기를 이용한 출석관리 시스템)

  • Um, Ik-Jung;Park, Yoon-Young;Heo, Jin-Man;Yoon, Nam-Sik;Lee, Chang-Jin;Han, Cheol-Ho
    • Annual Conference of KIPS
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    • 2011.04a
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    • pp.53-56
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    • 2011
  • 본 논문에서는 얼굴 인식을 위해 제작된 임베디드 단말기와 모바일 환경에서 사용할 수 있는 안드로이드용 애플리케이션을 구현하여 얼굴 인식용 임베디드 단말기를 이용한 출석관리 시스템을 설계 및 제작하였다. 현재 진행중인 이 연구는 특수 기능을 위해 제작된 임베디드 단말기와 스마트폰에 장착되어 있는 카메라를 이용하여 얼굴을 촬영하고, 촬영된 사진을 PC 서버를 통하여 기존 데이터에 등록된 사람인지 아닌지를 판별하는 시스템이다. 이 시스템을 이용하여 인증 불가시 대리인증이나 결석 여부를 판별할 수 있는 출석관리뿐만 아니라, 근태관리 시스템으로도 사용하는 것을 목표로 하고 있다.

Implementation of E.M.P.Z for Video Mashup (동영상을 매쉬업하기 위한 E.M.P.Z의 구현)

  • Lee, Sun-Soo;Kim, Jong-Hyun;Lee, Gun-Joo;Lee, Chang-Hoon;Choi, Hyun-Sik;Hwang, Suk-Hyung
    • Annual Conference of KIPS
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    • 2011.11a
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    • pp.1403-1404
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    • 2011
  • 본 논문에서는 동영상과 다양한 데이터들을 매쉬업하여 통합미디어컨텐츠(UMC : United Media Contnets)를 수월하게 제작하고 재생시켜주는 E.M.P.Z(Editor Media Player Zone)의 개발에 대해 기술한다. E.M.P.Z는 에디터를 사용하여 다양한 데이터를 편집하는 기능과 UMC를 재생하기 위한 플레이어 기능, 그리고 웹기반환경에서 검색 및 플레이기능 등을 제공하며, 학습을 위한 동영상강의, 스포츠중계, 광고 등의 다양한 분야에서 활용 가능하다.