• Title/Summary/Keyword: 통신기기

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The Case on Valuation of IT Enterprise (IT 기업의 가치평가 사례연구)

  • Lee, Jae-Il;Yang, Hae-Sul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.4
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    • pp.881-893
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    • 2007
  • IT(Information Technology)-based industries have caused a recent digital revolution and the appearance of various types' information service, being largely expanded toward info-communication device company, info-communication service company, software company etc.. Therefore, the needs to evaluate the company value of IT business for M&A or liquidation are growing tremendously. Unlike other industries, however, IT industry has a short lift cycle and so it doesn't have not only a company value-evaluating model for general businesses but the objective one for IT companies yet. So, this thesis analyzes various value-evaluating technique and newly rising ROV. DCF, the change method of company's cash flow including tangible assets into future value, had been applied during the past industrialization economy era and has been persuasively applied to the present. However, the DCF valuation has no option but to make many mistakes because IT companies have more intangible assets than tangible assets. Accordingly, it is ROV, recognized as the new method of evaluating companies' various options normally and quantitatively, that is brought up recently. But the evaluation on the companies' various options is too subjective and theoretical up to now and due to the lack of objective ground and options, it's not possible to be applied to reality. In this thesis, it is found that ROV is more accurate than DCF, comparing DCF and ROV through four examples. As the options applied to ROV are excessively limited, we tried to develop ROV into a new method by deriving five invisible value factors within IT companies. Therefore, on this occasion, we should set up the basic valuation methods on IT companies and should research and develop an effective and various valuation methods suitable to each company like an internet-based company, a S/W developing enterprise, a network-related company among IT companies.

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Comparison of Measured and Calculated Carboxylation Rate, Electron Transfer Rate and Photosynthesis Rate Response to Different Light Intensity and Leaf Temperature in Semi-closed Greenhouse with Carbon Dioxide Fertilization for Tomato Cultivation (반밀폐형 온실 내에서 탄산가스 시비에 따른 광강도와 엽온에 반응한 토마토 잎의 최대 카복실화율, 전자전달율 및 광합성율 실측값과 모델링 방정식에 의한 예측값의 비교)

  • Choi, Eun-Young;Jeong, Young-Ae;An, Seung-Hyun;Jang, Dong-Cheol;Kim, Dae-Hyun;Lee, Dong-Soo;Kwon, Jin-Kyung;Woo, Young-Hoe
    • Journal of Bio-Environment Control
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    • v.30 no.4
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    • pp.401-409
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    • 2021
  • This study aimed to estimate the photosynthetic capacity of tomato plants grown in a semi-closed greenhouse using temperature response models of plant photosynthesis by calculating the ribulose 1,5-bisphosphate carboxylase/oxygenase maximum carboxylation rate (Vcmax), maximum electron transport rate (Jmax), thermal breakdown (high-temperature inhibition), and leaf respiration to predict the optimal conditions of the CO2-controlled greenhouse, for maximizing the photosynthetic rate. Gas exchange measurements for the A-Ci curve response to CO2 level with different light intensities {PAR (Photosynthetically Active Radiation) 200µmol·m-2·s-1 to 1500µmol·m-2·s-1} and leaf temperatures (20℃ to 35℃) were conducted with a portable infrared gas analyzer system. Arrhenius function, net CO2 assimilation (An), thermal breakdown, and daylight leaf respiration (Rd) were also calculated using the modeling equation. Estimated Jmax, An, Arrhenius function value, and thermal breakdown decreased in response to increased leaf temperature (> 30℃), and the optimum leaf temperature for the estimated Jmax was 30℃. The CO2 saturation point of the fifth leaf from the apical region was reached at 600ppm for 200 and 400µmol·m-2·s-1 of PAR, at 800ppm for 600 and 800µmol·m-2·s-1 of PAR, at 1000ppm for 1000µmol of PAR, and at 1500ppm for 1200 and 1500µmol·m-2·s-1 of PAR levels. The results suggest that the optimal conditions of CO2 concentration can be determined, using the photosynthetic model equation, to improve the photosynthetic rates of fruit vegetables grown in greenhouses.

Fabrication of Portable Self-Powered Wireless Data Transmitting and Receiving System for User Environment Monitoring (사용자 환경 모니터링을 위한 소형 자가발전 무선 데이터 송수신 시스템 개발)

  • Jang, Sunmin;Cho, Sumin;Joung, Yoonsu;Kim, Jaehyoung;Kim, Hyeonsu;Jang, Dayeon;Ra, Yoonsang;Lee, Donghan;La, Moonwoo;Choi, Dongwhi
    • Korean Chemical Engineering Research
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    • v.60 no.2
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    • pp.249-254
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    • 2022
  • With the rapid advance of the semiconductor and Information and communication technologies, remote environment monitoring technology, which can detect and analyze surrounding environmental conditions with various types of sensors and wireless communication technologies, is also drawing attention. However, since the conventional remote environmental monitoring systems require external power supplies, it causes time and space limitations on comfortable usage. In this study, we proposed the concept of the self-powered remote environmental monitoring system by supplying the power with the levitation-electromagnetic generator (L-EMG), which is rationally designed to effectively harvest biomechanical energy in consideration of the mechanical characteristics of biomechanical energy. In this regard, the proposed L-EMG is designed to effectively respond to the external vibration with the movable center magnet considering the mechanical characteristics of the biomechanical energy, such as relatively low-frequency and high amplitude of vibration. Hence the L-EMG based on the fragile force equilibrium can generate high-quality electrical energy to supply power. Additionally, the environmental detective sensor and wireless transmission module are composed of the micro control unit (MCU) to minimize the required power for electronic device operation by applying the sleep mode, resulting in the extension of operation time. Finally, in order to maximize user convenience, a mobile phone application was built to enable easy monitoring of the surrounding environment. Thus, the proposed concept not only verifies the possibility of establishing the self-powered remote environmental monitoring system using biomechanical energy but further suggests a design guideline.

A study on the developmental plan of Alarm Monitoring Service (기계경비의 발전적 대응방안에 관한 연구)

  • Chung, Tae-Hwang;So, Seung-Young
    • Korean Security Journal
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    • no.22
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    • pp.145-168
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    • 2010
  • Since Alarm Monitoring Service was introduced in Korea in 1981, the market has been increasing and is expected to increase continually. Some factors such as the increase of social security need and the change of safety consciousness, increase of persons who live alone could be affected positively on Alarm Monitoring Service industry. As Alarm Monitoring Service come into wide use, the understanding of electronic security service is spread and consumer's demand is difficult, so consideration about new developmental plan is need to respond to the change actively. Electronic security system is consist of various kinds of element, so every element could do their role equally. Alarm Monitoring Service should satisfy consumer's various needs because it is not necessary commodity, also electronic security device could be easily operated and it's appearance has to have a good design. To solve the false alarm problem, detection sensor's improvement should be considered preferentially and development of new type of sensor that operate dissimilarly to replace former sensor is needed. On the other hand, to settle the matter that occurred by response time, security company could explain the limit on Alarm Monitoring System to consumer honestly and ask for an understanding. If consumer could be joined into security activity by security agent's explanation, better security service would be provided with mutual confidence. To save response time the consideration on the introduction of GIS(Global Information System) is needed rather than GPS(Global Positioning System). Although training program for security agents is important, several benefits for security agents should be considered together. The development of new business model is required for preparation against market stagnation and the development of new commodity to secure consumer for housing service rather than commercial facility service. for the purpose of those, new commodity related to home-network system and video surveillance system could be considered, also new added service with network between security company and consumer for a basis is to be considered.

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Design of Intersection Simulation System for Monitoring and Controlling Real-Time Traffic Flow (실시간 교통흐름의 모니터링 및 제어를 위한 교차로 시뮬레이션 시스템 설계)

  • Jeong Chang-Won;Shin Chang-Sun;Joo Su-Chong
    • Journal of Internet Computing and Services
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    • v.6 no.6
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    • pp.85-97
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    • 2005
  • In this paper, we construct the traffic information database by using the acquired data from the traffic information devices installed in road network, and, by referring to this database, propose the intersection simulation system which can dynamically manage the real-time traffic flow for each section of road from the intersections, This system consists of hierarchical 3 parts, The lower layer is the physical layer where the traffic information is acquired on an actual road. The traffic flow control framework exists in the middle layer. The framework supports the grouping of intersection, the collection of real-time traffic flow information, and the remote monitoring and control by using the traffic information of the lower layer, This layer is designed by extending the distributed object group framework we developed. In upper layer, the intersection simulator applications controlling the traffic flow by grouping the intersections exist. The components of the intersection application in our system are composed of the implementing objects based on the Time-triggered Message-triggered Object(TMO) scheme, The intersection simulation system considers the each intersection on road as an application group, and can apply the control models of dynamic traffic flow by the road's status. At this time, we use the real-time traffic information collected through inter-communication among intersections. For constructing this system, we defined the system architecture and the interaction of components on the traffic flow control framework which supports the TMO scheme and the TMO Support Middleware(TMOSM), and designed the application simulator and the user interface to the monitoring and the controlling of traffic flow.

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A Study on File Transfer Methods on IEEE-1394 Serial Bus (IEEE-1394 버스에서의 파일 전송 기법에 연구)

  • 편기현;강성일;이흥규
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10a
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    • pp.261-263
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    • 1998
  • IEEE-1394 버스(이하 13394 버스)는 가정용 가전기기와 컴퓨터를 서로연결 할 수 있는 버스로 100Mbps, 200Mbps, 400Mbps의 광대역폭을 제공하고 데이터를 전달하는 방법으로 비동기 (asynchromous)전송뿐만 아니라 등시성(isochronous)전송도 제공한다. 비동기 전송은 시간의 제약이 없고 정확한 전달이 필요한 데이터에 적합한 반면 등시성 전송은 실시간을 요구하고정확한 전잘이 필요없는 데이터에 적합한 특성을 가진다. 1394 버스는 멀티미디어 데이터를 생성하고 편집하는 장치들을 서로 연결시키고 기존의 LAN이 갖는 대역폭의 부족과 프로토콜살의 실시간 전송 방법의 부재 때문에 진정한 의미의 실시간 구현이 어려웠던 화상 전화기, 화상회의 시스템, 비디오편집 시스템을 가능하게 한다. 이러한 멀티미디어 응용 시스템은1)대용향의 멀티미디어 파일 전송을 필요로 하고 화상전화기 혹은 화상회의 시스템은 2) 고속의 파일 전송을 요구하게 된다. 또 두사람이 화상 전화기를 통해 통신을 하면서 여러 가지 문서를 교환하는 경우 최대한 빠르게 파일 전송이 완료될 필요가 있다. 현재 1394버스에서 IP가 올리는 일이 진행중이므로 기존의 FTP는 사용할 수 없다. 게다가 1394 버스에 IP가 올라가더라도 1394 버스 내에서 대용량의 파일을 더 빠르고 정확하게 전달하기 위해서는 IP오버헤드가 없고 1394 버스의 특성을 직접 이용한 새로운 파일 전송 기법이 필요하다. 1394 버스내에서 대용량의 파일을 빠르고 정확하게 전송하는 기법을 찾기 위해서는 비동기 전송과 등기성 전송의 특성을 잘 이해해야하고 각 전송 방법으로 파일을 전송 할 때 생기는 장단점들을 파악해야한다. 본 논문에서는 비동기 전송과 등기성 전송을 이용한 팔일 전송 기법을 각각 제시하고 실험을 통해 이들의 특성을 비교분석하였다.미에서 uronic acid 함량이 두 배 이상으로 나타났다. 흑미의 uronic acid 함량이 가장 많이 용출된 분획은 sodium hydroxide 부분으로서 hemicellulose구조가 polyuronic acid의 형태인 것으로 사료된다. 추출획분의 구성단당은 여러 곡물연구의 보고와 유사하게 glucose, arabinose, xylose 함량이 대체로 높게 나타났다. 점미가 수가용성분에서 goucose대비 용출함량이 고르게 나타나는 경향을 보였고 흑미는 알칼리가용분에서 glucose가 상당량(0.68%) 포함되고 있음을 보여주었고 arabinose(0.68%), xylose(0.05%)도 다른 종류에 비해서 다량 함유한 것으로 나타났다. 흑미는 총식이섬유 함량이 높고 pectic substances, hemicellulose, uronic acid 함량이 높아서 콜레스테롤 저하 등의 효과가 기대되며 고섬유식품으로서 조리 특성 연구가 필요한 것으로 사료된다.리하였다. 얻어진 소견(所見)은 다음과 같았다. 1. 모년령(母年齡), 임신회수(姙娠回數), 임신기간(姙娠其間), 출산시체중등(出産時體重等)의 제요인(諸要因)은 주산기사망(周産基死亡)에 대(對)하여 통계적(統計的)으로 유의(有意)한 영향을 미치고 있어 $25{\sim}29$세(歲)의 연령군에서, 2번째 임신과 2번째의 출산에서 그리고 만삭의 임신 기간에, 출산시체중(出産時體重) $3.50{\sim}3.99kg$사이의 아이에서 그 주산기사망률(周産基死亡率)이 각각 가장 낮았다. 2. 사산(死産)과 초생아사망(初生兒死亡)을 구분(區分)하여 고려해 볼때 사산(死産)은 모성(母性)의 임신력(姙娠歷)과 매우 밀접한 관련이 있는 것으로 사료(思料)되었고 초생아사망(初生兒死亡)은 미숙아(未熟兒)와 이에 관련된 병발이 거의 결정

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u-EMS : An Emergency Medical Service based on Ubiquitous Sensor Network using Bio-Sensors (u-EMS : 바이오 센서 네트워크 기반의 응급 구조 시스템)

  • Kim, Hong-Kyu;Moon, Seung-Jin
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.7
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    • pp.433-441
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    • 2007
  • The bio-Sensors, which are sensing the vital signs of human bodies, are largely used by the medical equipment. Recently, the sensor network technology, which composes of the sensor interface for small-seize hardware, processor, the wireless communication module and battery in small sized hardware, has been extended to the area of bio-senor network systems due to the advances of the MEMS technology. In this paper we have suggested a design and implementation of a health care information system(called u-EMS) using a bio-sensor network technology that is a combination of the bio-sensor and the sensor network technology. In proposed system, we have used the following vital body sensors such as EKG sensor, the blood pressure sensor, the heart rate sensor, the pulse oximeter sensor and the glucose sensor. We have collected various vital sign data through the sensor network module and processed the data to implement a health care measurement system. Such measured data can be displayed by the wireless terminal(PDA, Cell phone) and the digital-frame display device. Finally, we have conducted a series of tests which considered both patient's vital sign and context-awared information in order to improve the effectiveness of the u-EMS.

A Study of Shielding Property of Magnetic Field for the Film Impregnated with Soft Magnetic Powder (연자성 합금분말을 함침시킨 필름의 자계 차폐 특성 연구)

  • Park, Jong-Hyun;Ra, Keuk-Hwan;Kang, Eun-Kyun;Kim, Jin-Woo
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.1
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    • pp.211-218
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    • 2014
  • In this paper the magnetic field properties of the soft magnetic alloys (Fe-Si-Cr and Fe-Ni-Cr) are studied in advance for the development of electro-magnetic shielding films, which could be used in the IT Devices (NFC, mobile phone, computer, etc.).As a result each of the selected soft magnetic alloy melts of the corresponding compositions is water-dispersed into the disk-shaped grains, which are soaked in polymer resin, and of which two types of thin film of thickness 0.1mm and 1mm are made by passing through the heating calendar roller. And the magnetic permeability and the shielding effectiveness of the polymer films containing the soft magnetic alloy grains are measured over the whole frequency bands from the low frequency to 10GHz. Before the experiments of the soft magnetic alloy, a special equation is proposed to estimate the permeability of the alloy, and the equation is verified with the pre-published data by MATLAB, and from which the most optimal compositions can be decided. And the SE(Shielding Effectiveness) of the polymer films containing the soft magnetic alloy grains is simulated by the HFSS.

An Exploratory Study on the Proper Length of Article in Mobile Era (모바일 시대의 기사 길이에 관한 탐색적 연구)

  • Cheong, Yeon Goo;Cheong, Ye Hyun;Guo, YaQi;Lee, Pu Reum
    • Korean journal of communication and information
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    • v.79
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    • pp.140-164
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    • 2016
  • What is an appropriate length of an article in the mobile era producing new tastes of contents combining computing and mobile communication? Is it still valid to have a lengthy article as high level journalism even in the mobile era? Is there any possibility to have a short article combination to give us readability and the amount of information? This study aims to find some answers to these questions. The length of articles were controlled with a field experiment; from an article of 346 syllables(including spaces between syllables) which does not need finger scrolling on a mobile phone to articles of 633, 1033, 1368 syllables(including spaces between syllables) which frequently appear in newspapers and broadcasting news program. All the main themes were same for 4 articles which have different length. Three hundred and eighty four students viewed one of the 4 articles through mobile phone or newspaper. Each participant checked their preference and evaluated quality on the article, were asked to recall contents of the article. In newspaper group, articles with 346 or 1033 syllables were highly evaluated. Mobile group seemed to prefer articles of 346 or 633 syllables. In conclusion, we need to consider various strategies shortening the length of an article into 346 or 633 syllables as a basic format to meet the neEds of mobile era.

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A Study of Factors Influencing on Digital Textbook Satisfaction of Elementary School (초등학생의 디지털교과서 활용 만족도에 영향을 미치는 변인 분석)

  • Song, Moonhyeon;Kim, Jamee;Kim, Hyeoncheol
    • Journal of The Korean Association of Information Education
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    • v.19 no.3
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    • pp.287-298
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    • 2015
  • Digital textbook is noted as a new education materials to realize a new education paradigm with changes in digitalized society. The purposes of this study is investigation of key factors on digital textbook satisfaction by selecting of the three factors(domestic environment factor, teachers factor, school environment factor), analysis of awareness of effect factors on digital textbook satisfaction, and verification for each effect factors' influence on elementary school. 201 elementary school students, 201 their parents, and 12 teachers in Chung-nam were surveyed and factors which influenced on digital textbook satisfaction were analyzed. According to the results, firstly, there was a statistical significant difference in domestic internet environment, device owned environments, the utilization of the internet for the purpose of education and using time, device type of teachers, lesson time of digital textbook used in class and time ratio. Secondly, multiple regression analysis was conducted to find out the influence on digital textbook, the Awareness of parents about digital textbook, The lesson time using digital textbook by teacher, The utilization of the internet for the purpose of education affected satisfactions significantly in the order. This study has significant implications about which we have provided the effort needed to use digital textbook.