• 제목/요약/키워드: modem

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A Design of Wireless Sensor Node Using Embedded System (임베디드 시스템을 활용한 무선 센서 노드설계)

  • Cha, Jin-Man;Lee, Young-Ra;Park, Yeon-Sik
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제13권3호
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    • pp.623-628
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    • 2009
  • The emergence of compact and low-power wireless communication sensors and actuators in the technology supporting the ongoing miniaturization of processing and storage allows for entirely the new kinds of embedded systems. These systems are distributed and deployed in environments where they may have been designed into a particular control method, and are often very dynamic. Collection of devices can communicate to achieve a higher level of coordinated behavior. Wireless sensor nodes deposited in various places provide light, temperature, and activity measurements. Wireless sensor nodes attached to circuits or appliances sense the current or control the usage. Together they form a dynamic and multi-hop routing network connecting each node to more powerful networks and processing resources. Wireless sensor networks are a specific-application and therefore they have to involve both software and hardware. They also use protocols that relate to both applications and the wireless network. Wireless sensor networks are consumer devices supporting multimedia applications such as personal digital assistants, network computers, and mobile communication devices. Wireless sensor networks are becoming an important part of industrial and military applications. The characteristics of modem embedded systems are the capable of communicating adapting the different operating environments. In this paper, We designed and implemented sensor network system which shows through host PC sensing temperature and humidity data transmitted for wireless sensor nodes composed wireless temperature and humidity sensor and designs sensor nodes using embedded system with the intention of studying USN.

Holocene sea-level rise and paleoenvironmental changes in Korea Strait shelf (대한해협 대륙붕 해역의 홀로세 해수면 상승과 고환경변화)

  • 남승일;장정해;공기수;김성필;유동근
    • The Korean Journal of Quaternary Research
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    • 제17권1호
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    • pp.7-16
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    • 2003
  • A 31m-long sediment core (SSDP-102) was taken from the inner shelf (about 40m water-depth) off the northwestern coast of the Korea Strait. Detailed lithofacies and organic-geochemical analyses were performed to establish a high-resolution stratigraphy in the Korea Strait shelf and to reconstruct the paleoenvironmental changes associated with the Holocene marine transgression. The stratigraphic framework of the core was primarily established using 6 AMS $^{14}C$ ages. The sedimentary record of the core SSDP-102 allows for the reconstruction of the paleoenvironmental changes during the last 12.1 ka BP. According to the high-resolution seismic reflection profiles, lithofacies and organic-geochemical data, the core SSDP-102 can be divided into three units (III to I in ascending order) above the acoustic basement. The three units reflect distinct changes of depositional environments resulted from the post-glacial marine transgression. Therefore, it is suggested that three phases of sea-level change have occurred within the inner shelf of the Korea Strait following the Holocene marine transgression. (1) estuarine environments from ca. 12.1 to 6.2 ka BP; (2) near-shore environments with a period of decreased rising of sea level between 6.2 and 5.1 ka BP; (3) near-shore to modem marine environments after 5.1 ka BP. In particular, the present marine conditions influenced by the warm Tsushima Current have been gradually established after ca. 5.1 ka BP.

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Textural Characters of the Sediments from Neolithic site Moonamni Coastal Zone, East Sea of Korea -Implication of the Holocene High Stand Sea Level (강원도 동해안 문암리 신석기 유적지 퇴적층의 조직 특성)

  • 박용안;김수정;최진용
    • The Korean Journal of Quaternary Research
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    • 제17권1호
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    • pp.27-37
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    • 2003
  • The Neolithic relics containing sedimentary deposits have been found in the Moonamni coastal zone of the East Sea, Korea. The purpose of this research is to establish the late Quaternary stratigraphy of the coastal dune deposit and to elucidate its depositional environment of the Neolithic-site sediments on the basis of analytical properties of grain size population and mineralogy of the sediments. As a result, the vertical sections of the sediments from three trenches are characterized by three major stratigraphic depositional units of Unit 3, Unit 2 and Unit 1 in ascending order. Unit 3 and 2 can be further divided into tow sub-units. Unit 3 is composed of massive sands in the lower part and muddy sand in the upper part. It is considered that the Unit 3 is a typical dune deposit showing well-sorted sands. Unit 2 is characterized by the cross-bedding, and include archaeological remains such as pottery shards. This unit can be further divided into two sub-units of muddy sand in the lower part and sand in the upper part. Unit 1 occupies the top section and consists of modem dune sediment. The Neolithic cultural remains would be accumulated in the coastal dune area in relation to dynamic condition of beach system under the high stand of Holocene sea-level at about 7,800∼6,500 yr B.P. or so.

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The Cultural Revolution and the Political Map of the Minority Nationality Region : A Case Study on the Inner Mongolia Autonomous District and the Oroqen Autonomous Banner (문화대혁명(文化大革命)과 소수민족지구(少數民族地區)의 정치지도(政治地圖) : 내몽고자치구와 어룬춘자치기의 사례)

  • Lee, Kang-Won
    • Journal of the Korean association of regional geographers
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    • 제8권1호
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    • pp.1-19
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    • 2002
  • The Cultural Revolution(wenhuadageming) is one of the most important political movement in the modem China. The studies on the movement done in recent years concentrated on the political conspiracy or the struggle over political line, so they did not pay attention to the political geographical dimension of the movement. This paper proposes that the Cultural Revolution practised in the area of minority nationalities at least is well understood through the political geographical perspective. Through the discussion on the Cultural Revolution practised in the Inner Mongolia autonomous district and the Oroqen minority nationality autonomous banner, this paper suggest that the socialist Chinese leader group considers the frontier area(bianjiang) or the minority nationality regions(xiaoshuminzudiqu) important as 'region' or 'space' not as 'the area of minority nationalities (minzu)'. Especially, in the period of the movement, the leader group of the revolution manipulated the space by using the index of nationality or manipulated the nationality by using the index of space. Therefore this paper assert that the Cultural Revolution in the area of minority nationality autonomous region was a integration process of the people and national territory through the reorganization of the nationalities into classes and of autonomous region into region in general meaning.

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Segregation of the Lowest Social Class and Transformation of Communal Consciousness : As a Case Study of Douwa District in Yao City, Osaka (사회적 최하층계급의 거주지분리와 공동체의식의 변화 : 대판부(大阪府) 팔미시(八尾市)의 동화지구를 사례로)

  • Jo, Hyun-Mi
    • Journal of the Korean association of regional geographers
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    • 제15권6호
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    • pp.803-819
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    • 2009
  • This study explores of the lowest social class segregation in the residential area of Yao city of the Osaka Prefecture. The Buraku people, who constitute a social class that was the object of societal discrimination and exclusion since the beginning of modem times, formed a segregated residential area of their own. During the process of an organized struggle against discrimination that was institutionally recognized, communal consciousness among the constituents was consolidated. Moreover, in the Yao city, Korean immigrants in Japan, another discriminated group, as well as Vietnamese refugees and Chinese, who are also social minorities, increased in number. Also, activities by the Buraku people and Korean immigrants in Japan to defend human rights and the rights of social minorities began to unfold. Recently, the number of small scale factories in the Buraku's Douwa District decreased due to relocation of manufacturing companies elsewhere throughout Japan and to the effects of depression. New non-Buraku houses began to appear one by one on the site where factories started to disappear. While the spatial separatism of Yao city, as part of the isolated Douwa District, is weakening, the struggle based on communal consciousness among the social minorities and continued human rights activity is exerting great influence upon the administrative policy of Yao city. In the case of Yao city, while the visual appearance of spatial segregation is weakening, the communal consciousness among the regional residents remains. From this perspective, it can be said that this case represents a modified form of isolated space or the social pattern of segregation which is in the stage of extinction.

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A Study on the Flexural Capacity of Reinforced Timber Beams with the Inserting Method of CFRP Plates (탄소섬유판 삽입공법으로 보강된 목재보 휨강도에 관한 연구)

  • Kwon, Ki-Hyuk;Yu, Hye-Ran;Lee, Jin-Hyuk;Choi, Min-Seok
    • Journal of the Korean Society of Hazard Mitigation
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    • 제8권1호
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    • pp.1-7
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    • 2008
  • When historical or cultural buildings need to be repaired or reinforced, the changes of original features should be minimized, and the strengths of structures should be improved. Among the existing methods to reinforce historical wood structures, the carbon fiber reinforcement polymer (CFRP) installation method is one of the best ones to achieve the afore-mentioned requirements. Therefore, this study aims at investigating the reinforcing effects and failure modes of timber beams reinforced with the inserted CFRP, a part of roof trusses in modern wood structures, and at providing the fundamental test data to estimate the CFRP rein-forced timber beam in the application of this reinforcing method. The primary parameters in this study were the layout and amount of CFRP. It was observed that, when $0.3{\sim}0.7%$ of CFRP were installed, the strengths of reinforced timber beams increased up to 173% compared to its original strength, but their strengthening effects were heavily influenced by the characteristics of timber such as burls. In order to improve the applicability of this strengthening method, fundamental understandings on the characteristics of wood would be necessary, and there would be in need of researches on the non-destructive test for wood structures as well.

Development of a Real-time OS Based Control System for Laparoscopic Surgery Robot (복강경 수술로봇을 위한 실시간 운영체제 기반 제어 시스템의 개발)

  • Song, Seung-Joon;Park, Jun-Woo;Shin, Jung-Wook;Kim, Yun-Ho;Lee, Duk-Hee;Jo, Yung-Ho;Choi, Jae-Seoon;Sun, Kyung
    • Journal of Biomedical Engineering Research
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    • 제29권1호
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    • pp.32-39
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    • 2008
  • This paper reports on a realtime OS based master-slave configuration robot control system for laparoscopic surgery robot which enables telesurgery and overcomes shortcomings with conventional laparoscopic surgery. Surgery robot system requires control system that can process large volume information such as medical image data and video signal from endoscope in real-time manner, as well as precisely control the robot with high reliability. To meet the complex requirements, the use of high-level real-time OS (Operating System) in surgery robot controller is a must, which is as common as in many of modem robot controllers that adopt real-time OS as a base system software on which specific functional modules are implemened for more reliable and stable system. The control system consists of joint controllers, host controllers, and user interface units. The robot features a compact slave robot with 5 DOF (Degree-Of-Freedom) expanding the workspace of each tool and increasing the number of tools operating simultaneously. Each master, slave and Gill (Graphical User Interface) host runs a dedicated RTOS (Real-time OS), RTLinux-Pro (FSMLabs Inc., U.S.A.) on which functional modules such as motion control, communication, video signal integration and etc, are implemented, and all the hosts are in a gigabit Ethernet network for inter-host communication. Each master and slave controller set has a dedicated CAN (Controller Area Network) channel for control and monitoring signal communication with the joint controllers. Total 4 pairs of the master/slave manipulators as current are controlled by one host controller. The system showed satisfactory performance in both position control precision and master-slave motion synchronization in both bench test and animal experiment, and is now under further development for better safety and control fidelity for clinically applicable prototype.

A Study on the Concentration of CO(Carbon Monoxide) by the Length of the Straight Exhaust Tube for Gas Boiler (가스보일러 직관 배기통의 길이에 따른 폐가스(CO)농도 고찰)

  • Leem, Sa-Hwan;Huh, Yong-Jeong;Lee, Jong-Rark;Kim, Cheol-Jin;Park, In-Soo;Ha, Tae-Young;Kim, Il-Woo;Choi, Rack-Bum
    • Journal of the Korean Institute of Gas
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    • 제11권2호통권35호
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    • pp.5-9
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    • 2007
  • There have been 3E problems of energy, economy and environment since the earth has its history. Especially, the energy and environment problems have been getting serious after the modem industry revolution. Therefore, the demand of gas as an eco-friendly energy source is getting increased. With the demand of gas, the installation and use of gas boiler is also increased, so human life injury by the waste gas(CO) of boiler goes on increasing every you. Hence, we want to find out the harm to human body through the study on the concentration of CO by the length of the straight exhaust tube of gas boiler. The allowable concentration of CO is 50 ppm. The 3 m of once bended tube starts exceeding the allowable concentration of CO after 5 minutes, and the 4 m and 5 m starts exceeding after 3 minutes.

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A Quality Comparison of Traditional Korean Papers: Mixtures of Bast-Fiber with Straw pulp(Rice straw paper) in Different Composition Ratio (고정(藁精) 혼합비율에 따른 한지의 물성 비교)

  • Jung, Sun-Young
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • 제39권1호
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    • pp.48-55
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    • 2007
  • The aim of this article is to review the general property of the famous traditional Korean paper, "rice straw paper"(Bast-Fiber mixed with straw pulp), and to compare the paper qualities varying with the composition ratio of straw pulp, in order to revive the traditional paper in modem Korea. The experiment was carried out by making first the two different mixture papers, i. e., one is the paper of 50% bast fiber mixed with 50% straw pulp, and the other is the paper of 75% bast fiber with 25% oats straw pulp, and finally the 100% bast fiber paper was made for the purpose of comparison. The qualitative properties of these three kinds of paper with the different mixing ratio of the straw pulp were evaluated, and the findings of the experiment can be summarized as follow: 1. As to the quality aspects of the paper strength like tensile strength, breaking length, elongation, and tear strength, the test proved the 100% bast fiber paper as best, and the 50% mixed paper as the next good one. 2. In aspect of the printing adaptability such as density, opacity, brightness, whiteness, lab colors, air permeability, and roughness, the 50% mixed paper proved to be the best, due to the short cells in the straw pulp. 3. As to the air permeability, the larger ratio of straw pulp was found to be the lesser, and 75% bast fiber with 25% straw pulp mixture paper and the 100% bast fiber one were found 1/5 degree efficient. 4. In terms of the water absorption degree, 100% bast fiber paper was the fastest, but in case of mixture paper, 50% mixed one was a little faster up to the point of 1cm, while the two kinds of mixed ones appear to be almost similar to each other beyond the point. 5. The straw pulp mixed paper, especially the 50% mixed one was evaluated as the highest by the calligraphers who had experienced using the papers in terms of movement and feeling of the caligraphy and painting. In addition, although the 25% mixed paper is judged to be good for book printing because of the strength, the 50% mixed paper can be thought to be more desirable for painting and calligraphy. In conclusion, we will be able to make the quality paper with durability, by mixing the straw pulp with the bast fiber in proper ratio, following the tradition of Korean paper making.

A Use-case based Component Mining Approach for the Modernization of Legacy Systems (레거시 시스템을 현대화하기 위한 유스케이스 기반의 컴포넌트 추출 방법)

  • Kim, Hyeon-Soo;Chae, Heung-Seok;Kim, Chul-Hong
    • Journal of KIISE:Software and Applications
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    • 제32권7호
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    • pp.601-611
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    • 2005
  • Due to not only proven stability and reliability but a significant investment and years of accumulated -experience and knowledge, legacy systems have supported the core business applications of a number of organizations over many years. While the emergence of Web-based e-business environments requires externalizing core business processes to the Web. This is a competitive advantage in the new economy. Consequently, organizations now need to mine the business value buried in the legacy systems for reuse in new e-business applications. In this paper we suggest a systematic approach to mining components that perform specific business services and that consist of the legacy system's assets to be leveraged on the modem platform. The proposed activities are divided into several tasks. First, use cases that realize the business processes are captured. Secondly, a design model is constructed for each identified use case in order to integrate the use cases with the similar functionalities. Thirdly, we identify component candidates from the design model and then adjust the component candidates by considering common elements among the candidate components. And also business components are divided into three more fine-grained components to deploy them onto J2EE/EJB environments. finally, we define the interfaces of components which provide functionalities of the components as operations.