• 제목/요약/키워드: Network-engine

검색결과 480건 처리시간 0.026초

위성의 전이궤도 열해석 (TRANSFER ORBIT THERMAL ANALYSIS FOR SATELLITE)

  • 전형열;김정훈;김성훈;양군호
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2007년도 추계 학술대회논문집
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    • pp.227-231
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    • 2007
  • COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and has been developing by KARI for communication and ocean and meteorological observations. It will be launched by ARIANE 5. Ka-band components are installed on South panel, where single solar array wing is mounted. Radiators, embedded heat pipes, external heat pipe, insulation blankets and heaters are utilized for the thermal control of the satellite. The Ka-band payload section is divided several areas based on unit operating temperature in order to optimize radiator area and maximize heat rejection capability. Other equipment for sensors and bus are installed on North panel. The ocean and meteorological sensors are installed on optical benches on the top floor to decouple thermally from the satellite. During the transfer orbit operation, satellite will be under severe thermal environments due to low dissipation of components, satellite attitudes and LAE(Liquid Apogee Engine) firing. This paper presents temperature and heater power prediction and validation of thermal control design during transfer orbit operation.

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New Trends and Challenges of Internet Marketing

  • Nosshi, Anthony;Saad, Aziza;Senousy, M. Badr
    • Asia pacific journal of information systems
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    • 제25권2호
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    • pp.337-355
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    • 2015
  • The Internet has become one of the most important channels for people to communicate and for companies to implement their sales promotion activities, such as advertising. Marketing and advertising attempt to influence customers' attitude to persuade them to choose to buy the advertisers' products instead of the competitors'. With the different forms of online marketing, such as search engine marketing, email marketing, and mobile marketing, advertisers can find more effective strategies to attract the attention of more targeted audiences. With the emergence of the social web (web 2.0), a new platform was introduced called social networks. This paper presents the current work in internet marketing activities until web 2.0, and conducts a social network analysis to aid in data extraction. Marketing and advertising companies have understood the power of information for a very long time. The more knowledge these companies have on the demographics, consumer habits, and preferences of particular customer types, the more they can tailor their product offerings, and the more sales they can make. This paper aims to understand the internet marketing concepts as well as present challenges and work directions in internet marketing.

가정용 지능형 경비 로봇 시스템 개발 (Development of an Intelligent Security Robot System for Home Surveillance)

  • 박정호;신동관;우춘규;김형철;권용관;최병욱
    • 제어로봇시스템학회논문지
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    • 제13권8호
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    • pp.810-816
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    • 2007
  • A security robot system named EGIS-SR is a mobile security robot through one of the new growth engine project in robotic industries. It allows home surveillance through an autonomous mobile platform using onboard cameras and wireless security sensors. EGIS-SR has many sensors to allow autonomous navigation, hierarchical control architecture to handle lots of situations in monitoring home surveillance and mighty networks to achieve unmanned security services. EGIS-SR is tightly coupled with a networked security environment, where the information of the robot is remotely connected with the remote cockpit and patrol man. It achieved an intelligent unmanned security service. The robot is a two-wheeled mobile robot and has casters and suspension to overcome a doorsill. The dynamic motion is verified through $ADAMS^{TM}$ simulation. For the main controller, PXA270 based hardware platform based on linux kernel 2.6 is developed. In the linux platform, data handling for various sensors and the localization algorithm are performed. Also, a local path planning algorithm for object avoidance with ultrasonic sensors and localization using $StarGazer^{TM}$ is developed. Finally, for the automatic charging, a docking algorithm with infrared ray system is implemented.

퍼지 제어를 이용한 ATM망에서 PM에 관한 연구 (A Study on Policing Mechanism in ATM Network using Fuzzy Control)

  • 신관철;박세준;양태규
    • 한국정보통신학회논문지
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    • 제5권5호
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    • pp.931-940
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    • 2001
  • 본 논문에서는 ATM 네트워크에서 예측할 수 없고 폭주가 가능한 입력의 트래픽 제어를 위한 Fuzzy Policing Mechanism(FPM)을 제안한다. FPM은 카운터, 감산기와 퍼지논리제어기(FLC)로 구성된다 FLC는 퍼지화기, 추론 엔진, 비퍼지화기로 구성된다. FLC의 출력은 감산기에 입력되어 카운터상태를 일정하게 조절하며 카운터는 셀의 전송을 제어하게 된다. 시뮬레이션에서는 Fluid Flow 방법에 의한 Leaky Bucket algorithm(LBM)과 FPM의 셀 손실 확률과 특성성능을 비교하였다. 시뮬레이션 결과, FPM은 LBM보다 작은 셀 손실 확률을 얻었으며 가변적인 트래픽 자원을 효율적으로 제어했다. 그리고 특성성능에서 FPM이 좋은 응답 특성 및 선택도를 보였다.

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NMEA2000을 이용한 임베디드 선박 모니터링 시스템의 개발 (Development of Embedded Vessel Monitoring System Using NMEA2000)

  • 이창의;김달용;유영호;신옥근
    • Journal of Advanced Marine Engineering and Technology
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    • 제33권5호
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    • pp.746-755
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    • 2009
  • Recently, NMEA2000 became the de facto standard of the communication protocol for the instrument level network in vessels, and it is anticipated that most of the vessels will be equipped with the sensors and actuators based on this protocol. The conventional serial communication specifications such as RS-232, RS-485, or even NMEA0183 are single-talker/multiple-listener and interconnection among multiple sensors and/or actuators usually results in a bundle of wires. On the other hand, NMEA2000 is a true bus type(multiple-talker/multiple-listener) protocol and theoretically up to 256 instruments can be hot-plugged. With the advent of the protocol, it is necessary to consider a new type of monitoring system for the instruments in vessels: In most traditional serial communication environments, a dedicated monitor or user interface was necessary for each sensor or actuator as it was simply not easy to collect data in a single place. With NMEA2000, the collection of various types of information is simple. An embedded system can be employed to combine, to arrange and to display informations from various types of devices. Assuming that the actuators and sensors on a vessel are interconnected by NMEA2000 standard, we devise a tentative interactive vessel monitoring system in which the following 4 kinds of informations are collected and delivered: the navigation, engine, weather and tanks informations.

ELPA: Emulation-Based Linked Page Map Analysis for the Detection of Drive-by Download Attacks

  • Choi, Sang-Yong;Kim, Daehyeok;Kim, Yong-Min
    • Journal of Information Processing Systems
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    • 제12권3호
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    • pp.422-435
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    • 2016
  • Despite the convenience brought by the advances in web and Internet technology, users are increasingly being exposed to the danger of various types of cyber attacks. In particular, recent studies have shown that today's cyber attacks usually occur on the web via malware distribution and the stealing of personal information. A drive-by download is a kind of web-based attack for malware distribution. Researchers have proposed various methods for detecting a drive-by download attack effectively. However, existing methods have limitations against recent evasion techniques, including JavaScript obfuscation, hiding, and dynamic code evaluation. In this paper, we propose an emulation-based malicious webpage detection method. Based on our study on the limitations of the existing methods and the state-of-the-art evasion techniques, we will introduce four features that can detect malware distribution networks and we applied them to the proposed method. Our performance evaluation using a URL scan engine provided by VirusTotal shows that the proposed method detects malicious webpages more precisely than existing solutions.

Movie Recommendation System Based on Users' Personal Information and Movies Rated Using the Method of k-Clique and Normalized Discounted Cumulative Gain

  • Vilakone, Phonexay;Xinchang, Khamphaphone;Park, Doo-Soon
    • Journal of Information Processing Systems
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    • 제16권2호
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    • pp.494-507
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    • 2020
  • This study proposed the movie recommendation system based on the user's personal information and movies rated using the method of k-clique and normalized discounted cumulative gain. The main idea is to solve the problem of cold-start and to increase the accuracy in the recommendation system further instead of using the basic technique that is commonly based on the behavior information of the users or based on the best-selling product. The personal information of the users and their relationship in the social network will divide into the various community with the help of the k-clique method. Later, the ranking measure method that is widely used in the searching engine will be used to check the top ranking movie and then recommend it to the new users. We strongly believe that this idea will prove to be significant and meaningful in predicting demand for new users. Ultimately, the result of the experiment in this paper serves as a guarantee that the proposed method offers substantial finding in raw data sets by increasing accuracy to 87.28% compared to the three most successful methods used in this experiment, and that it can solve the problem of cold-start.

소아를 주요 대상으로 하는 한의원 웹사이트의 분석 및 고찰 (Analysis of Oriental Pediatrics Clinic Web Sites in Korea)

  • 김장현;서영민
    • 대한한방소아과학회지
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    • 제20권2호
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    • pp.45-57
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    • 2006
  • Objectives : The Internet is closely related to the live of modern people in the 21st Century. With increasing interest in health and disease of children, the public has access to a growing supply of information on oriental pediatrics clinic through Internet. The purpose of this study is to collect and analyze the Internet web sites concerning oriental pediatrics clinic in Korea, and study the effectiveness of internet toward oriental pediatrics. Methods : We selected 42 web sites by searching for such keyword as child and oriental Medical clinic at korea major web search engine. The sites were evaluated and analyzed on the basis of 24 is under three evaluation criteria such as quality of contents, the easy of use, reliability of web sites. Results: Study results indicated that 34% of web sites were built in 2004, 58% of oriental pediatrics clinic was located in Seoul & Kyunggi and 84% of them was connected network medical system. About health information was supplied in oriental pediatrics clinic web sites, the growth was high frequent information, 50% of web sites supplied high quality information and 19% of them was supplied high diversity information. Conclusions: It is necessary to control system as information certification system in the area of oriental pediatrics clinic web sites.

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신 개발 차종에 대한 소비자 음질평가 예측에 관한 연구 (The Research for Predicting Customer's Evaluation of Sound Quality for a New Vehicle)

  • 이상권;조병옥;박동철;이민섭;정승균
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.1437-1442
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    • 2006
  • The international competition in car markets has continuously required the research about the sound quality of a car. The domestic carmakers have also invested a lot of money for the research and development of interior sound quality of passenger cars. Therefore, the aim of this research is to predict the customer's evaluation of a new vehicle. There are two major research works to achieve this goal in this research. The first one is to search questionnaires about the sound quality, which customers prefer, to identify the relationship between these questionnaires and sound metrics that is a psychoacoustics parameters, and to development sound indexes for the questionnaires. All tests for this work is proceed on the road test during acceleration. The second one is to balance the sound component (engine noise, booming noise, road noise and wind noise) of a passenger. This wok will be tested on the constant speed. All of research results will be contributed to the development of brand sound quality of a new passenger car.

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디지털보호계전기를 이용한 기중차단기 제어 및 모니터링 (Control And Monitoring Of Air Circuit Breaker Using Digital Protective Relay)

  • 이성환;박상배;안인석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 A
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    • pp.240-242
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    • 2001
  • On this research, to catch up with international trend on the power system utilities move to be digitalized and move to network is certainly technological on the global business world, to compete with advanced foreign countries in the range of transmit and distribute power system and to take possession of first market share within country, we talked over a monitoring system to diagnose, monitor ACB(Air Circuit Breaker) only which is operated on the low level voltage Power plant. AMS(ACB Monitoring System) have be configured with several modules such as engine module which acquire engineering data from HICM360/860(Communication Control Units) and analyze and save it, database module which restore data and can be inquired, system monitoring view module which reflects fields information within a second, realtime trend window, historical trend window, reports as daily and yearly. In a near future, AMS must upgrade GUI to have easy to handle and have to have a field test to fit on real plants, so it will have faith in system reliability as it can apply power plant monitoring system in wide.

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