• Title/Summary/Keyword: Space Technology(ST)

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국제우주법의 기본특성과 정책환경 분석

  • Ju, Seong-Hwan
    • Satellite Communications and Space Industry
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    • v.2 no.3
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    • pp.83-92
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    • 1994
  • Outer Space is existing as the opening-up frontier. The space activities included benefit-and-risk are now confronted with the challenge of arriving at just and effective rules for the use of space serving many technical, practical and conflicting legal, economic, political and military interests. Therefore many governments have developed domestic and international policies to respond to the opportunities and constraints engendered by space exploration and exploitation. the challenges of outer space toward the 21st century are being internationalized, commercialized, and privatized, militarized through the international cooperation and competition in space activities. For the future of mankind, futhermore the right to live of humankind, we must be positively interested in international space law which may give rise to international repercussions. I suggeste that many issues be resolved by international coordinating organization.

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Comparison of Efficiency for Different Switching Tables in Six-Phase Induction Motor DTC Drive

  • Taheri, Asghar;Rahmati, Abdolreza;Kaboli, Shahriyar
    • Journal of Power Electronics
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    • v.12 no.1
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    • pp.128-135
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    • 2012
  • In this paper, different switching tables proposed for the Direct Torque Controlled (DTC) of a six-phase induction machine are simulated and implemented. A six-phase induction motor has 64 space voltage vectors which result in increased complexity in the selecting of inverters switching. The unsuitable selection of a switching table leads to large harmonics especially at low speed and it also reduces drive efficiency. A six-phase induction machine has large zero sequence harmonic currents of the order $6{\kappa}{\pm}1$. These harmonic currents are varied in various techniques. Decreasing this loss is essential in a six-phase induction machine. The main purpose of this paper is to improve the ST-DTC of six-phase induction machines to reduce the voltage and current harmonics and the torque pulsation. Selecting a suitable method for minimizing these harmonics is very important.

Identification of two common types of forest cover, Pinus densiflora(Pd) and Querqus mongolica(Qm), using the 1st harmonics of a Discrete Fourier Transform

  • Cha, Su-Young;Pi, Ung-Hwan;Yi, Jong-Hyuk;Park, Chong-Hwa
    • Korean Journal of Remote Sensing
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    • v.27 no.3
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    • pp.329-338
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    • 2011
  • The time-series normalized difference vegetation index (NDVI) product has proven to be a powerful tool to investigate the phenological information because it can monitor the change of the forests with very high time-resolution, This study described the application of the DFT analysis over the 9 year MODIS data for the identification of the two types of vegetation cover, Pinus densiflora(Pd) and Querqus mongolica(Qm) which are dominant species of evergreen and broadleaved deciduous forest, respectively, The total number of samples was 5148 reference cycles which consist of 2160 Pd and 2988 Qm. They were extracted from the pixel-based MODIS scenes over the 9 years from 2000 to 2008 of South Korea. The DFT analysis was mainly focused on the 0th and $1^{st}$ harmonic components, each of which represents the mean value and the variation amplitude of the NDVI over the years, respectively. The $0^{th}$ harmonic values of the vegetation Pd and Qm averaged over the 9 years were 0.74 and 0.65, respectively. This implies that Pd has a higher NDVI than Qm. Similarly obtained $1^{st}$ harmonic values of Pd and Qm were 0.19 and 0.27, respectively. This can be intuitively understood considering that the seasonal variation of Qm is much larger than Pd. This distinctive difference of the $1^{st}$ harmonic value has been used to identify evergreen and deciduous forests. Overall agreement between the Fourier analysis-based map and the actal vegetation map has been estimated to be as high as 75%. This study found that the DFT analysis can be a concise and repeatable method to separate and trace the changes of evergreen and deciduous forest using the annual NDVI cycles.

Web-based Real Environment Monitoring Using Wireless Sensor Networks

  • Lee, Gil-Jae;Kong, Jong-Uk;Kim, Min-Ah;Byeon, Ok-Hwan
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.207-210
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    • 2005
  • Ubiquitous computing is one of the key technology areas in the "Project on Development of Ubiquitous computing and network technology" promoted by the Ministry of Science and Technology as a frontier business of the $21^{st}$ century in Korea, which is based on the new concept merging physical space and computer-based cyber space. With recent advances in Micro Electro Mechanical System (MEMS) technology, low cost and low-power consumption wireless micro sensor nodes have been available. Using these smart sensor nodes, there are many activities to monitor real world, for example, habitat monitoring, earthquake monitoring and so on. In this paper, we introduce web-based real environment monitoring system incorporating wireless sensor nodes. It collects sensing data produced by some wireless sensor nodes and stores them into a database system to analyze. Our environment monitoring system is composed of a networked camera and environmental sensor nodes, which are called Mica2 and developed by University of California at Berkeley. We have modified and ported network protocols over TinyOS and developed a monitoring application program using the MTS310 and MTS420 sensors that are able to observe temperature, relative humidity, light and accelerator. The sensed data can be accessed user-friendly because our environment monitoring system supports web-based user interface. Moreover, in this system, we can setup threshold values so the system supports a function to inform some anomalous events to administrators. Especially, the system shows two useful pre-processed data as a kind of practical uses: a discomfort index and a septicity index. To make both index values, the system restores related data from the database system and calculates them according to each equation relatively. We can do enormous works using wireless sensor technologies, but just environment monitoring. In this paper, we show just one of the plentiful applications using sensor technologies.

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The Study on the Development Trend of the Times toward Digital Clothing (디지털 의류[Digital Clothing]의 시대적 개발 경향 연구)

  • Kwak, Tai-Gi
    • Journal of the Korean Society of Costume
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    • v.59 no.4
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    • pp.111-125
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    • 2009
  • The period from the early years of the 21st Century, when the birth of Digital Clothing received as a kind of digital cultures in the modern information society, to the present time, the period is studied on as a social transition in the revolutionary digital technology in parallel with the fashion changes which have an effect on our thoughts and our life style. After the 2000's, when digital was perceived as a culture, information technology came into being owing to the technological development in the network and informative and communicative technology. This study tried to grasp the tendency of the times to Digital Clothing, which occurred in the new situation of Digital Technology, and then on the base of it, tried to classify the expressive characteristics in the Digital Clothing as the Cyberspace, Global Network, high functionality Smart Textiles and digital technology. The social reformation by the revolutionary digital technology is coming forth in the New Fashion of the digital Clothing, with the development of technology and network in the Cyberspace and real space. the Digital Clothing which led to the revolutionary change in New Fashion occurred, and by the same time, gradually the phenomena of Digital Consuming Culture is expansive.

Experimental Investigation for the Shroud Separation in the Supersonic Flow (초음속 비행환경 조건에서의 슈라우드 분리시험 연구)

  • Kim, Jung-Young;Lee, Dong-Min
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.45 no.7
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    • pp.539-549
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    • 2017
  • In this paper, experimental studies on the shroud separation were performed to investigate characteristics of the shroud separation at mach 3. Shroud separation tests were carried out in the vertical free-jet wind tunnel that is capable of testing separable structures. A shroud model was miniaturized to meet test objectives and test section dimensions of the wind tunnel. Pneumatic Locking and separation mechanisms were designed considering external force due to free stream. High speed cameras were used to record the shroud motion and unsteady shock patterns over the deploying shrouds during the shroud separation process. Also, unsteady pressures on the nose surface were measured by using the pressure sensors. Through the tests, the measurement data necessary for researches on the shroud separation technology were obtained. Shroud separation behaviors and characteristics of unsteady pressure on the nose surface for each external flow conditions were analyzed.

A study of the Investigation Offices' Planning Standard and Criteria of the Police Station - By Analyzing the Actual Situation Survey of the Prototypes - (경찰서 수사부서 표준설계 공간모형과 지침 연구 - 환경개선 시범사례 실태조사를 중심으로 -)

  • Cho, Hyeonmi
    • Korean Institute of Interior Design Journal
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    • v.27 no.1
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    • pp.140-155
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    • 2018
  • In response to the development of IT technology in the 21st century and the advancement of the public human rights consciousness, it has become necessary to continuously evolve the office environments to support the changes of organizational structure and work methods of the police investigation departments. As a facility standard, continuous researches on standardized design space models and guidelines of the police investigation departments are needed. In respond to the organizational changes for the convenience of the working police investigators and the protection of the human rights of the visiting public, the environmental improvement projects for the office of the investigation department of the police stations are going on since 2014. In this study, analyzation and verification of the 3 cases of pilot projects for the improvement of police investigation departments would be done, based on the policy research project in 2014: 'the standard design direction of police officers for the protection of human rights and benefit of police investigation process.' The purpose of this study is, first of all, the actual situation survey for presenting the standard design space model and guidelines of investigation department of the police department. Secondly, the validation of the spatial model adequacy for for the past 3 years' case study of the police investigation department's environmental improvements by the application of standardized design space models and guidelines. The result of this study would be to enable the more effective police department investigation environment improvement policy by presenting the standard design space models and guidelines of the investigation departments of the police facilities.

A Study on the educational direction of Dental Technology Department in the 21st century (21C 치과 기공과 교육의 방향에 대한 연구)

  • Park, J.H.
    • Journal of Technologic Dentistry
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    • v.21 no.1
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    • pp.153-163
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    • 1999
  • The 21st centurt, the era of change-space, is requesting us to readjust our education system. In other words, we should renew it by looking back into the past cultivate more advanced ideas. As a matter of fact junior colleges have been considered just as miniture of universities in every way such as curriculum, prossor emploment, school affairs, etc. Therefore we should change our existing education system not to be criticized for the next century. May students are trained for industry as dental technicians in our department of college. We should educate experiment and practice substantially as college professors as well as exert ourselves in developing our abilities to adapt to high diverse industrial technique, putting emphasis on practice more than theory. It is mecessary for us to sufficiently teach the technique to good students and make them display their abilities in order to produce high quality goods. Reinvestment ineducation is a condition precedent. Dental laboratories have just employed the students that graduated from our college. However it's time for a change. They should pay attention to our education and assist us in all respects with the thought of equally educating professional dental technicians together with us. The field practice system is subject to reinforcement so that our students have more opporunities of utilizing the tools and materials for practice. Finally we should not only carry out new reserch more deeply no less than dental technicians who are experienced in business for development of education system but endeavor to meet pratical education by adding what is pratically needed in dental laboratories to the existing education system.

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『The Death of a Salesman』 reinterpreted by Media Transformation: Focusing on (2017) by Asghar Farhadi (매체 변환을 통해 재해석된 『세일즈맨의 죽음』: 아쉬가르 파라디 감독의 영화 <세일즈맨>(2017))

  • Choi, Young-hee;Lee, Hyun-Kyung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.4
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    • pp.193-198
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    • 2022
  • Arthur Miller's play has been reproduced for a long time, and has been made into a film several times. Director Asghar Farhadi made a film set in Iran in the 21st century, showing the film (2017), which excludes "Death" from the original title. is not just a movie of . In , the play is summoned in the form of performing a play. There are many movies in this form, but is an exquisite fabrication so that the reality outside the play and the content in the play harmonize with each other. The play depicts the tragedy of the head of the family who falls at the end of the American dream. The movie transforms this tragedy into a conflict between a young couple living in Iran in the 21st century. In addition, is completed as an independent work that not only rearranged the space and characters of the original work, but also reinterpreted the meaning of death, creating the effect of media conversion such as theater and film.

The Issue of Treating Information by Digital Media in Contemporary Design (현대디자인에 있어서 디지털 미디어에 의한 정보처리의 문제)

  • 박기웅
    • Archives of design research
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    • v.15 no.3
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    • pp.201-212
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    • 2002
  • This thesis is to study about The Issue of Treating Information, according to the circumstance of Digital Media in Contemporary Design. The Digital Design is being able to be organized by developed Science and Technology. Ultra fashionable mode of digital design is leading human life more comfortable and serviceable: and proceeded by technology aheaded by science Developed Computer will help the Space science and virtual reality. and They will lead more developed industrial culture. The design is influencing international society and economic circumstance, and it's making the changedness of product and commercial route. virtual reality and simulation made by developed science is resulting in new design revolution in our society. Especially, it is able to make more bigger result in image breaking and reassimilation. The technology of developed information treating infra is able to transmit & receive a message, which are beyond our sensual boundary and is the meaning of the human-being's progressive development of science culture. Developed information treating methodology made by technology and science of restoration will be Neo-reality for artists and are the cause of great changedness in 21st century's art & design.

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