• Title/Summary/Keyword: pointing method

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PERFORMANCE OF THE SRAO 6-METER RADIO TELESCOPE

  • KOO BON-CHUL;PARK YONG-SUN;HONG SEUNG SOO;YUN HONG-SIK;LEE SANG-GAK;BYUN DO-YOUNG;LEE JUNG-WON;CHOI HAN-KyU;LEE SANG-SUNG;YOON YOUNG-ZOO;KIM KEE-TAE;KANG HYUN WOO;LEE JUNG-EuN
    • Journal of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.43-48
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    • 2003
  • We introduce and describe performance of the 6-meter telescope of Seoul Radio Astronomy Observatory (SRAO). All the softwares and instruments except the antenna structure and its driving system are developed for ourselves. The SIS mixer type receiver resulted in the receiver noise temperature less than 50 K (DSB) over the whole 3-mm radio window. An autocorrelation spectrometer, developed first in Korea, provides maximum 50 MHz band width over 1024 channels. Antenna surface is measured and adjusted using template method and radio holography which resulted in a superb surface accuracy bet-ter than 30${\mu}m$. Accordingly, the aperture and beam efficiences amount to $70\%$ and $75\%$, respectively, largely independent of frequency in the 85 - 115 GHz range. It is also found that telescope pointing errors are less than 10" in both azimuth and elevation and that antenna gain is almost constant against elevation greater than $20^{\circ}$, without adjusting sub-reflector position. The SRAO 6-meter telescope is now fully operational and all these characteristics verify that observations are carried out with high precision and fidelity.

The Effect of Reflection and Mentoring Based on Gender - Sensitive Teaching Strategies (성인지적 교수전략을 바탕으로 한 수업 성찰과 멘토링 효과)

  • Hong, Kyung-Sun;Kim, Dong-Ik;Gu, Su-Yeon;Ahn, Jin-Kyung
    • Journal of Engineering Education Research
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    • v.14 no.2
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    • pp.40-50
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    • 2011
  • This study is to investigate an effective instruction for female students in an engineering classroom through gender -sensitive teaching strategies by analysing recorded classroom instruction, reflective journals of professor, and mentoring instructions of A professor teaching "non-steel materials and design" in an engineering classroom. This study which used a qualitative approach for data collection and analysis showed changes of A professor in his way of teaching. The changes are: making rough lesson plan ${\rightarrow}$ making detailed lesson plan being satisfied with his teaching skills ${\rightarrow}$ trying to improve his teaching skills, using negative feedback ${\rightarrow}$ using positive feedback, pointing weaknesses as pre-engineers ${\rightarrow}$ providing detailed information needed to be engineers. This paper deals with the theory comparison between a conventional engineering education and new engineering education, in which conventional models may fail to give satisfactory results. Finally, we provide real application examples to evaluate the feasibility and generality of the proposed method in this paper.

Development of Korean Preliminary Lunar Mission Design Software (한국형 달탐사 임무 예비 설계 소프트웨어의 개발)

  • Song, Young-Joo;Park, Sang-Young;Choi, Kyu-Hong;Shim, Eun-Seop
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.36 no.4
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    • pp.357-367
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    • 2008
  • Preparing for future Korean Lunar missions, preliminary Lunar mission design software is developed using a impulsive thrusting method. Developed software is capable of design and analysis every required mission phases to design Lunar mission, including the Earth departure, Lunar transfer, Lunar arrival and mission operation phases. Also, assuming that KSLV-II is selected as a launch vehicle, future Korean Lunar explorer's mass budget is estimated based on driven optimal trajectory characteristics. Tracking analysis is also performed using Deep Space Network including angle geometry analysis between Earth - Moon - Lunar explorer - Sun which are very important for communication, solar panel pointing strategy and eclipse analysis when Lunar missions are under designing phase.

PRECISION IDENTIFICATION OF ACTUATOR DISTURBANCE PARAMETER BY FREQUENCY COMPENSATION (주파수 보정법에 의한 구동기 외란 파라미터 정밀 결정)

  • Lee Hyunho;Cheon Dong-Ik;Oh Hwa-Suk
    • Bulletin of the Korean Space Science Society
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    • 2005.04a
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    • pp.138-142
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    • 2005
  • A reaction wheel, an actuator for satellite attitude control, produces disturbance torque and force as well as its axial control torque. The disturbances have an influence on the pointing stability of high precision satellites. The measurement of disturbances for such a satellite, therefore, is necessary. The wheel's rotation, however, causes the vibration of the table and its vibration induces measurement errors, especially large near the resonance frequency of the Measurement table. For the purpose of overcoming these defects, a calibration method using frequency compensation is suggested in this paper. Disturbance parameters are identified from data examined by frequency compensation. Measurement frequency range can be expanded far higher than the resonance frequency, since the degradation of data accuracy caused by its vibration is well alleviated even in the resonance area.

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A Study on the Theory of Stomach and Lung in Suwen·Kailun (『소문(素問)·해론(欬論)』의 '취어위(聚於胃), 관어폐(關於肺)' 조문(條文)에 대한 고찰(考察))

  • Baik, Yousang;Kim, Jong-hyun
    • Journal of Korean Medical classics
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    • v.30 no.3
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    • pp.167-180
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    • 2017
  • Objectives : The purpose of this paper is to extinguish the debates surrounding the sentences found in Suwen Kailun that deal with flocking to stomach and closure in lung. The paper seeks to do this through studying the assertions of historical doctors and their theories regarding the topic. Methods : The interpretations of annotators regarding these sentences were studied, and text DB was searched to collect and analyze materials related to the theories of the relationship between stomach and lung. Results : The sentences of flocking to stomach and closure in lung, judging from their contexts, seem to be related to the symptom of Sanjiao ke or Liufu ke. However, they may be pointing to internal organs' ke as a whole based on the close relationship between stomach and lung. They could mean either the abnormality of mechanism of stomach and lung could cuase ke or that Zhuoqi could accumulate inside of stomach to cause phlegm-fluids thereby blocking thorax and causing cough. Theory of Warm disease, too, provides a number of treatment suggestions for stomach, lung damages such as supporting Yin and dispersing dampness. Conclusions : The study of the sentences regarding flocking to tomach and closure in lung is expected to not only provide an analysis of the sentences, but also provide a perspective and a method for clinical treatments.

Statistical Properties of Geomagnetic Activity Indices and Solar Wind Parameters

  • Kim, Jung-Hee;Chang, Heon-Young
    • Journal of Astronomy and Space Sciences
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    • v.31 no.2
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    • pp.149-157
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    • 2014
  • As the prediction of geomagnetic storms is becoming an important and practical problem, conditions in the Earth's magnetosphere have been studied rigorously in terms of those in the interplanetary space. Another approach to space weather forecast is to deal with it as a probabilistic geomagnetic storm forecasting problem. In this study, we carry out detailed statistical analysis of solar wind parameters and geomagnetic indices examining the dependence of the distribution on the solar cycle and annual variations. Our main findings are as follows: (1) The distribution of parameters obtained via the superimposed epoch method follows the Gaussian distribution. (2) When solar activity is at its maximum the mean value of the distribution is shifted to the direction indicating the intense environment. Furthermore, the width of the distribution becomes wider at its maximum than at its minimum so that more extreme case can be expected. (3) The distribution of some certain heliospheric parameters is less sensitive to the phase of the solar cycle and annual variations. (4) The distribution of the eastward component of the interplanetary electric field BV and the solar wind driving function BV2, however, appears to be all dependent on the solar maximum/minimum, the descending/ascending phases of the solar cycle and the equinoxes/solstices. (5) The distribution of the AE index and the Dst index shares statistical features closely with BV and $BV^2$ compared with other heliospheric parameters. In this sense, BV and $BV^2$ are more robust proxies of the geomagnetic storm. We conclude by pointing out that our results allow us to step forward in providing the occurrence probability of geomagnetic storms for space weather and physical modeling.

A Study on preference of Italian Cuisine (이태리 요리의 선호도 분석 및 운영개선방안에 관한 연구 )

  • 정진우
    • Culinary science and hospitality research
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    • v.2
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    • pp.169-181
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    • 1996
  • Today we are inclined to dine out more frequently according as the national income is increased and Women enter into the Social life, 'This tendency results in the universality of foodculture and the food made of fresh food stuff as well as the Pollution-free food is preferable as everyone warits to eat natural food or health food and escapes from the pollution. Moreover we have socail problems like fatress and adult disease which result from the small amount of activity or the food with high calory and high gat. under this circumstance. the most adeguate food seems to be Italian good. It stand in the spottight of food world and is most preferable for everyone today. The sphere of food and beverage has a low value-added-rate compartry to the high increasing rate of customers and profit, so, the efficient managing method for the cost of food and beverage and the operating skill in the kitchen are the principal factors leading to success or failure. Therefore, this research is to show some remedies as follows, pointing out the operating problems of an selected Italian restaurant at the top class hotel. First, most Italian restaurant at the hotel are located in the best place and investing the big capital, But they are open for only 8 hours through a day. This should be improved not to bring a enormous loss to the hotel The brealefast menus such as vegetables or fish food, pizza and pasta which modern man can easily enjoy should be developed open the restaurants for morning gours. Second, the business hours are not made continously. As a result, all the emplyees should stay in the company all day long without taking any advantage of the losed time, This will be the loss for both the company and the employees, By veloping the morning menus, employees shald be classified into morning and afternoon staffs and the opening and closing hour at 3 and 6 O'clock should be used so that minimum number of employees may operate the company. Third, the characteristic of Italian food is in the use of fresh food stuff, The proper purchase of food stuff and the simple distributing system will help Italian restaurant show its character istcc as a hzgh-grade restaurant. Fourth, the most popular Italian food such as pizza or pasta should be market with Priority.

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PERFORMANCE OF THE TRAO 13.7-M TELESCOPE WITH NEW SYSTEMS

  • Jeong, Il-Gyo;Kang, Hyunwoo;Jung, Jaehoon;Lee, Changhoon;Byun, Do-Young;Je, Do-Heung;Kang, Sung-Ju;Lee, Youngung;Lee, Chang Won
    • Journal of The Korean Astronomical Society
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    • v.52 no.6
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    • pp.227-233
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    • 2019
  • We report the performance of the 13.7-meter Taeduk Radio Astronomy Observatory (TRAO) radio telescope. The telescope has been equipped with a new receiver, SEQUOIA-TRAO, a new backend system, FFT2G, and a new VxWorks operating system. The receiver system features a 16-pixel focal plane array using high-performance MMIC preamplifiers; it shows very low system noise levels, with system noise temperatures from 150 K to 450 K at frequencies from 86 to 115 GHz. With the new backend system, we can simultaneously obtain 32 spectra, each with a velocity coverage of 163 km s-1 and a resolution of 0.04 km s-1 at 115 GHz. The new operating system, VxWorks, has successfully handled the LMTMC-TRAO observing software. The main observing method is the on-the-fly (OTF) mapping mode; a position-switching mode is available for small-area observations. Remote observing is provided. The antenna surface has been newly adjusted using digital photogrammetry, achieving a rms surface accuracy better than 130 ㎛. The pointing uncertainty is found to be less than 5" over the entire sky. We tested the new receiver system with multi-frequency observations in OTF mode. The aperture efficiencies are 43±1%, 42±1%, 37±1%, and 33±1%, the beam efficiencies are 45±2%, 48±2%, 46±2%, and 41±2% at 86, 98, 110, and 115 GHz, respectively.

Oral Cancer Awareness of the General Public in Gorakhpur City, India

  • Agrawal, Mamta;Pandey, Sushma;Jain, Shikha;Maitin, Shipra
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.10
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    • pp.5195-5199
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    • 2012
  • Objectives: Global cancer statistical data show that India has one of the highest incidence rates of oral cancer worldwide. Early detection is extremely important as it results in lower morbidity and death rates. The present study was undertaken to assess awareness of oral cancer and knowledge of its early signs and risk factors in the general public of the semi-urban Gorakhpur area of Uttar Pradesh (India). It was also intended to educate the same population for early detection by increasing their ability to recognize signs and risk factors. Method: A questionnaire-based household survey was conducted over a period of one month in different parts of Gorakhpur district, a region where tobacco use is apparently very high. A total of 2,093 persons participated in the survey. The collected data were analyzed using SPSS software to assess and associate oral cancer awareness with the prevalence, and abstract risk factors, as well as other confounding variables. Results: The general awareness, knowledge of signs and risk factors of oral cancer were found to be proportionate to the literacy level with the highest rate of awareness being among high school and graduates and lowest among illiterates. It was also observed that on most of these dimensions the younger age groups (<30 years) were significantly more knowledgeable. Conclusion: Overall, the awareness of oral cancer in the high-risk population of Gorakhpur was not satisfactory, pointing to a need for further dissemination of information on this issue and its associated risks. This is especially important for the youngsters, as this may possibly help them keep away from the deleterious habit of tobacco indulgence in any form. If necessary risk factor cessation counselling should be provided.

A Study on the Effective Visual Form Following the Numerical Information Types (수치정보 유형에 따른 효과적인 시각적 형태 연구)

  • Kim, Jae-Young;Kim, Duk-Yong
    • The Journal of the Korea Contents Association
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    • v.16 no.4
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    • pp.624-633
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    • 2016
  • Although a number of information is emerging in the big data era and studies on the infographic studies for delivering it effectively are becoming an issue, the visualization study on the numerical information delivered through the credit card statement is very poor compared to its importance. The effective visualization method following each information characteristics was by analyzing the numerical information types focusing on the credit card statement. The type of the figure information classified into the comparative analysis, progress of time change, proportion, relationship, scope, and distribution, and it was made into the graph form proper to the nature of each information to study the most effective and ideal visual form. Therefore, this study is significant because it suggests a control point of the visualization by pointing out an effective visual form for delivering the numerical information that appears on the credit card statement with the figure characteristics.