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A Power Control-Based MF-TDMA Resource Allocation Scheme for Next Generation Military Satellite Communication Systems (차기 군 위성통신망 체계에서 이기종 단말 운용을 고려한 전력제어 기반 MF-TDMA 자원할당 기법)

  • Woo, Soon;Park, Hyung-Won;Lee, Ho-Sub;Yoo, Youn-Sang;Jung, Byung-Gi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37C no.11
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    • pp.1138-1147
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    • 2012
  • In this paper, an efficient power control based MF-TDMA resource allocation scheme is proposed for next generation military satellite communication systems. The proposed scheme has the flexibility is used to support heterogeneous terminals with differ in transmission capabilities. The method can be divided into two parts : burst size calculation and burst structure determination. At first, we estimate the link budget taken into account a dynamic satellite link state variation. Then, applicable ACM level and burst size is chosen. In burst structure determination phase, we reorganize the burst structure in time-frequency domain by controlling limited power, bandwidth, time resources. In particular, we compensate the power spectral density among different terminals to integrate them in same transponder, Furthermore, we increase the packing efficiency by controlling the ACM level of the burst in applicable power spectral density range. Simulation results show that the method increase the spectral efficiency and burst packing efficiency. In addition, slot allocation rejection ratio is successfully reduced.

Business Ecosystem-focused Commercialization Strategy for Real-time Monitoring and Detection Technology for Landslides (실시간 산사태 모니터링 및 탐지기술에 대한 비즈니스 생태계 기반 기술사업화 전략 연구)

  • Sawng, Yeong-Wha;Lim, Dong-Hyun;Chae, Byung-Gon;Choi, Junghae
    • The Journal of Engineering Geology
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    • v.26 no.2
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    • pp.223-233
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    • 2016
  • This study establishes a commercialization strategy for technology that can monitor and detect landslides in real time. An effective commercialization strategy was sought through both qualitative and quantitative analyses. The qualitative analysis considered the business environment in detail, while the quantitative analysis examined technologically strong and weak areas by visualizing the links between IPC (International Patent Classification) code structure and patent applicants. The results from both analyses are considered together, with particular attention paid to the business environment. The resulting integrated analysis comprehensively explores the degree of technological development and the current state of real-time monitoring and detection technology for landslides. The integrated analysis identified complementary assets in the business environment, as there is strong development and many research entities in this area. This suggests positive reinforcement for commercialization with two sub-strategies: (1) exploring demand with complementary assets, and (2) providing technology information for explored demand, which should facilitate successful commercialization. Exploiting this positive reinforcement for technology commercialization could reduce the high uncertainty of the technology and the market, and thus increase the probability of successful commercialization. It is also expected to contribute to long-term success by strengthening collaboration between the supply and demand sides.

Development of Acquisition and Analysis System of Radar Information for Small Inshore and Coastal Fishing Vessels - Position Tracking and Real-Time Monitoring- (연근해 소형 어선의 레이더 정보 수록 및 해석 시스템 개발 -위치 추적 및 실시간 모니터링 -)

  • 이대재;김광식;신형일;변덕수
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.4
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    • pp.337-346
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    • 2003
  • This paper describes on the system and method for automatically tracking and real-time monitoring the position of target ships relative to the own ship using a PC based radar system that displays radar images and electronic charts together on a single PC screen. This system includes a simulator for generating the GGA and VTG information of target ships and a simulator for generating the TTM and OSD outputs from a ARPA radar and then host computer accepts NMEA0183 sentences on the maneuvering information of target ships from these simulators. The results obtained are summarized as follows;1. The system developed this study can be used as a range finder for measuring the distance between two ships and as a device for providing the maneuvering information such as distance and bearing to target ships from own ship on ECS screen. 2. From the result of position tracking for a selected target ship tracked with an update rate of 5 seconds using the $\alpha$-$\beta$ tracker, we concluded that the smoothing effect by the $\alpha$-$\beta$tracker was very effective and stable except in the time interval until about one minute after the target is detected. 3. From the fact that the real-time maneuvering information of tracked ship targets via a local area network (LAN) from a host computer installed a radar target extractor was successfully transferred to various monitoring computers of ship, we concluded that this system can be used as a sub-monitoring system of ARPA radar.

Vehicle Headlight and Taillight Recognition in Nighttime using Low-Exposure Camera and Wavelet-based Random Forest (저노출 카메라와 웨이블릿 기반 랜덤 포레스트를 이용한 야간 자동차 전조등 및 후미등 인식)

  • Heo, Duyoung;Kim, Sang Jun;Kwak, Choong Sub;Nam, Jae-Yeal;Ko, Byoung Chul
    • Journal of Broadcast Engineering
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    • v.22 no.3
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    • pp.282-294
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    • 2017
  • In this paper, we propose a novel intelligent headlight control (IHC) system which is durable to various road lights and camera movement caused by vehicle driving. For detecting candidate light blobs, the region of interest (ROI) is decided as front ROI (FROI) and back ROI (BROI) by considering the camera geometry based on perspective range estimation model. Then, light blobs such as headlights, taillights of vehicles, reflection light as well as the surrounding road lighting are segmented using two different adaptive thresholding. From the number of segmented blobs, taillights are first detected using the redness checking and random forest classifier based on Haar-like feature. For the headlight and taillight classification, we use the random forest instead of popular support vector machine or convolutional neural networks for supporting fast learning and testing in real-life applications. Pairing is performed by using the predefined geometric rules, such as vertical coordinate similarity and association check between blobs. The proposed algorithm was successfully applied to various driving sequences in night-time, and the results show that the performance of the proposed algorithms is better than that of recent related works.

The proposal of download based IPTV system using user-specific channel management (사용자 맞춤형 채널 관리를 이용한 다운로드 기반의 IPTV 시스템 제안)

  • Kim, Dae-Jin;Choi, Hong-Sub
    • Journal of Digital Contents Society
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    • v.10 no.1
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    • pp.61-71
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    • 2009
  • While the broadband network and multimedia technology are being developed, the commercial market on digital contents as well as IPTV has been widely spreading. Especially IPTV is providing various useful services since it makes using multimedia contents easier and more convenient by combining the strong points of both TV and PC system. Until now, IPTV system has been focused on VoD service as a general usages. However, various IPTV services are recently demanded since they can have special features for some specific places and occasions. So in this paper, we propose a design of the download based IPTV system using user-specific channel management. At first, program contents previously scheduled by users are downloaded and are played at settop-box according to the prescribed time table. This system has some advantages of giving users easy access to any wanted media contents in anytime that is IPTV's characteristics. And we can increase stability of services by using time slot distributed download for contents. Because this service can be constructed and maintained at relatively low cost, we confirm that this service model is more suitable to some companies with small infrastructure and special purposes. Accordingly, in this paper, we look into necessary elements and define some protocols for system in order to help other developer build this system.

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The Legal Protection Scope and Limitation of Information (정보의 법적 보호범위와 한계)

  • Kim, Hyung-Man;Yang, Myung-Sub
    • Journal of Digital Convergence
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    • v.10 no.11
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    • pp.691-699
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    • 2012
  • "Information", which is circulated in society by information technology development represented by computer, has brought innovation not only to physical civilization, but also deep into our daily lives. This is to say that information has brought fundamental change to its form of existence, and value system through being faster regarding the circulation and the way of management being diverse. As time goes by, this kind of change would stimulate more changes to be made as the development of scientific civilization. Therefore, informatization is one of the important characteristic that defines modern society's essence, but on the other side, information has been taken advantage of that temperament and abused in a lot of different ways. "The Law Regarding Computer Network Diffusion Expansion and Usage Promotion"(1986), as a counterplan of informatization is our nation's first Act about informatization, which enacts national policy and system about this issue. Since then, many laws has been enacted down to "Private Information Protection Act"(2011), forming a comprehensive system. The basic background of these laws are based upon the premise that even if the place where the information is managed is virtual space, rules that are considered valid in the real world should be basically applied in the virtual space. Therefore, the violation of the law in the real world is also considered the violation in the virtual space. This direction of current law regarding information is shared with both the theories and the reality. However, current law system and notion are based upon the premise that the law regards material objects, thus the characteristic of the information, which is "Immaterial Being" is not reflected. Also, the management and approach to this issue is allopathic, exposing many problems. Thus, this paper examines the way of protecting information stipulated in the current law, contemplates its protection scope and limitation, and seeks the direction of the improvement, based on the critical mind explained above.

Restoration Plan of Changwon and Nam Streams Based on the Results of Diagnostic Assessment (생태적 진단결과에 기초한 창원천과 남천의 복원계획)

  • An, Ji Hong;Lim, Chi Hong;Jung, Song Hie;Kim, A Reum;Woo, Dong Min;Lee, Chang Seok
    • Journal of Korean Society on Water Environment
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    • v.33 no.5
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    • pp.511-524
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    • 2017
  • This study was carried out for the purpose of creating a restoration plan to improve the ecological quality of the Changwon and Nam streams. Based upon the results of comprehensive diagnostic assessment, restoration priority was given to the upstream reach, where conservation status is relatively superior. Restoration level was usually determined to practice active restoration as conservation, and the states of both Changwon and Nam streams were not so good. Restoration plans, by reach, were classified into "upstream", "midstream", and "downstream" were suggested in both terms of horizontal section frame and vegetation-based on the result of diagnostic assessment and the reference information. "Upstream", "mid-stream" and the "downstream" of Changwon and Nam streams were classified into "small-gravel- mountainous", "small-sand-plain", and "small-clay-plain streams" respectively (based on scale, and substrate and slope of river bed). The spatial arrangement of vegetation was laid out in diagram form by reflecting micro-topography and the water level of the horizontal section of river. Information regarding species composition was recommended as dominant species, which appear frequently in three vegetation zones composed of herbaceous plants, shrubs and trees and sub-tree- dominated zones divided by reflecting disturbance regime, depending on position on the horizontal section of river. Moreover, there have been prepared not only plans to improve the terrestrial ecosystems around the streams but also plans to create ecological networks, which can serve to improve the ecologic quality of the whole regional environment by serving to connect streams and terrestrial ecosystems, a process probably necessary and definitely recommended to realize true (genuine) restoration. Plans for ecological parks and networks were prepared by mimicking the species composition of Alnus japanica community, Zelkova serrata community, Carpinus laxiflora community, Quercus aliena community, and Q. serrata community.

Magnetic Markers-based Autonomous Navigation System for a Personal Rapid Transit (PRT) Vehicle (PRT 차량을 위한 자기표지 기반 무인 자율주행 시스템)

  • Byun, Yeun-Sub;Um, Ju-Hwan;Jeong, Rag-Gyo;Kim, Baek-Hyun;Kang, Seok-Won
    • Journal of Digital Convergence
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    • v.13 no.1
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    • pp.297-304
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    • 2015
  • Recently, the demand for a PRT(Personal Rapid Transit) system based on autonomous navigation is increasing. Accordingly, the applicability investigations of the PRT system on rail tracks or roadways have been widely studied. In the case of unmanned vehicle operations without physical guideways on roadways, to monitor the position of the vehicle in real time is very important for stable, robust and reliable guidance of an autonomous vehicle. The Global Positioning System (GPS) has been commercially used for vehicle positioning. However, it cannot be applied in environments as tunnels or interiors of buildings. The PRT navigation system based on magnetic markers reference sensing that can overcome these environmental restrictions and the vehicle dynamics model for its H/W configuration are presented in this study. In addition, the design of a control S/W dedicated for unmanned operation of a PRT vehicle and its prototype implementation for experimental validation on a pilot network were successfully achieved.

USN's Efforts to Rebuild its Combat Power in an Era of Great Power Competition (강대국 간의 경쟁시대와 미 해군의 증강 노력)

  • Jung, Ho-Sub
    • Strategy21
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    • s.44
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    • pp.5-27
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    • 2018
  • The purpose of this paper is to look at USN's efforts to rebuild its combat power in the face of a reemergence of great powers competition, and to propose some recommendations for the ROKN. In addition to the plan to augment its fleet towards a 355-ships capacity, the USN is pursuing to improve exponentially combat lethality(quality) of its existing fleet by means of innovative science and technology. In other words, the USN is putting its utmost efforts to improve readiness of current forces, to modernize maintenance facilities such as naval shipyards, and simultaneously to invest in innovative weapons system R&D for the future. After all, the USN seems to pursue innovations in advanced military Science & Technology as the best way to ensure continued supremacy in the coming strategic competition between great powers. However, it is to be seen whether the USN can smoothly continue these efforts to rebuild combat strength vis-a-vis its new competition peers, namely China and Russian navy, due to the stringent fiscal constraints, originating, among others, from the 2011 Budget Control Act effective yet. Then, it seems to be China's unilateral and assertive behaviors to expand its maritime jurisdiction in the South China Sea that drives the USN's rebuild-up efforts of the future. Now, some changes began to be perceived in the basic framework of the hitherto regional maritime security, in the name of declining sea control of the USN as well as withering maritime order based on international law and norms. However, the ROK-US alliance system is the most excellent security mechanism upon which the ROK, as a trading power, depends for its survival and prosperity. In addition, as denuclearization of North Korea seems to take significant time and efforts to accomplish in the years to come, nuclear umbrella and extended deterrence by the US is still noting but indispensible for the security of the ROK. In this connection, the naval cooperation between ROKN and USN should be seen and strengthened as the most important deterrents to North Korean nuclear and missile threats, as well as to potential maritime provocation by neighboring countries. Based on these observations, this paper argues that the ROK Navy should try to expand its own deterrent capability by pursuing selective technological innovation in order to prevent this country's destiny from being dictated by other powers. In doing so, however, it may be too risky for the ROK to pursue the emerging, disruptive innovative technologies such as rail gun, hypersonic weapon... etc., due to enormous budget, time, and very thin chance of success. This paper recommends, therefore, to carefully select and extensively invest on the most cost-effective technological innovations, suitable in the operational environments of the ROK. In particular, this paper stresses the following six areas as most potential naval innovations for the ROK Navy: long range precision strike; air and missile defense at sea; ASW with various unmanned maritime system (UMS) such as USV, UUV based on advanced hydraulic acoustic sensor (Sonar) technology; network; digitalization for the use of AI and big data; and nuclear-powered attack submarines as a strategic deterrent.

Research on Text Classification of Research Reports using Korea National Science and Technology Standards Classification Codes (국가 과학기술 표준분류 체계 기반 연구보고서 문서의 자동 분류 연구)

  • Choi, Jong-Yun;Hahn, Hyuk;Jung, Yuchul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.1
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    • pp.169-177
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    • 2020
  • In South Korea, the results of R&D in science and technology are submitted to the National Science and Technology Information Service (NTIS) in reports that have Korea national science and technology standard classification codes (K-NSCC). However, considering there are more than 2000 sub-categories, it is non-trivial to choose correct classification codes without a clear understanding of the K-NSCC. In addition, there are few cases of automatic document classification research based on the K-NSCC, and there are no training data in the public domain. To the best of our knowledge, this study is the first attempt to build a highly performing K-NSCC classification system based on NTIS report meta-information from the last five years (2013-2017). To this end, about 210 mid-level categories were selected, and we conducted preprocessing considering the characteristics of research report metadata. More specifically, we propose a convolutional neural network (CNN) technique using only task names and keywords, which are the most influential fields. The proposed model is compared with several machine learning methods (e.g., the linear support vector classifier, CNN, gated recurrent unit, etc.) that show good performance in text classification, and that have a performance advantage of 1% to 7% based on a top-three F1 score.