• 제목/요약/키워드: Wireless Distribution System

검색결과 285건 처리시간 0.029초

Survey and Analysis of Mobile B2B Demand (모바일 B2B 수요에 대한 조사 분석 연구)

  • Kim, Chul-Whan
    • The Journal of Society for e-Business Studies
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    • 제10권2호
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    • pp.1-19
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    • 2005
  • Due to the phenomenal growth in mobile internet users, mobile business as a type of applications of mobile internet has attracted the related industries' and academic researchers' attentions. However, most researchers focus on the issues of Mobile B2C collecting survey questions from consumers or internet users. This paper points out that Mobile B2B has distinct service sector and analyzes the current trend and demand of Mobile B2B in Korea by collecting survey questionnaire from specialists in mobile industries and people in universities and research institutes. Survey fields include business, market, contents/application, research and development and legal system. According to the survey results, Mobile B2B business will rise in distribution, finance, sales, and logistics industries from the beginning of 2005 using wireless PDA and the important preconditions will be security, certification, and standardization.

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Design and Implementation of the Extended SLDS for Real-time Location Based Services (실시간 위치 기반 서비스를 위한 확장 SLDS 설계 및 구현)

  • Lee, Seung-Won;Kang, Hong-Koo;Hong, Dong-Suk;Han, Ki-Joon
    • Journal of Korea Spatial Information System Society
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    • 제7권2호
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    • pp.47-56
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    • 2005
  • Recently, with the rapid development of mobile computing, wireless positioning technologies, and the generalization of wireless internet, LBS (Location Based Service) which utilizes location information of moving objects is serving in many fields. In order to serve LBS efficiently, the location data server that periodically stores location data of moving objects is required. Formerly, GIS servers have been used to store location data of moving objects. However, GIS servers are not suitable to store location data of moving objects because it was designed to store static data. Therefore, in this paper, we designed and implemented an extended SLDS(Short-term Location Data Subsystem) for real-time Location Based Services. The extended SLDS is extended from the SLDS which is a subsystem of the GALIS(Gracefully Aging Location Information System) architecture that was proposed as a cluster-based distributed computing system architecture for managing location data of moving objects. The extended SLDS guarantees real-time service capabilities using the TMO(Time-triggered Message-triggered Object) programming scheme and efficiently manages large volume of location data through distributing moving object data over multiple nodes. The extended SLDS also has a little search and update overhead because of managing location data in main memory. In addition, we proved that the extended SLDS stores location data and performs load distribution more efficiently than the original SLDS through the performance evaluation.

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A Study on the Design of Data Collection System for Growing Environment of Crops (작물 근권부 생장 환경 Data 수집 시스템 설계에 관한 연구)

  • Lee, Ki-Young;Jeong, Jin-Hyoung;Kim, Su-Hwan;Lim, Chang-Mok;Lee, Sang-Sik
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • 제11권6호
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    • pp.764-771
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    • 2018
  • Domestic and foreign agricultural environments nowadays are undergoing various changes such as aging of agricultural population, increase of earned population, rapid climate change, diversification of agricultural product distribution structure, depletion of water resources and limited cultivation area. In order to respond to various environmental changes in recent agriculture, practical use of Smart Greenhouse to easily record, store and manage crop production information such as crop growing information, growth environment and agriculture work log, Interest is growing. In this paper, we propose a system that collects the situation information necessary for growth such as temperature, humidity, solar radiation, CO2 concentration, and monitor the collected data, which can be measured in the rhizosphere of the crop. We have developed a system that collects data such as temperature, humidity, radiation, and growth environment data, which are measured by data obtained from the rhizosphere measuring section of a growing crop and measured by a sensor, and transmitted to a wireless communication gateway of 400 MHz. We developed the integrated SW that can monitor the rhythm environment data and visualize the data by using cloud based data. We can monitor by graph format and data format for visualization of data. The existing smart farm managed crops and facilities using only the data within the farm, and this study suggested the most efficient growth environment by collecting and analyzing the weather and growth environment of the farms nationwide.

RFID System with Localization Function Based on Zigbee RSSI (Zigbee RSSI 기반의 위치추정 기능을 탑재한 RFID 시스템)

  • Kim, Tae-Yun;Hwang, Suk-Seung
    • The Journal of the Korea institute of electronic communication sciences
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    • 제11권12호
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    • pp.1201-1208
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    • 2016
  • Radio Frequency Identification (RFID) technology has a significant attraction throughout various industry sites, along with the development of wireless communication technologies. The typical applications of RFID include medical, logistics, and distribution, and, specially, it is effectively applied to non-contact environments, because it employs radio waves. Although, recently, construction cases of the RFID management systems for the inventory management of the construction materials have been increased, the related researches and experiments for the reused materials are not actively performed. In this paper, we propose the RFID system with the localization function for effectively managing the reuse of the construction materials, adding to the conventional inventory management system. The proposed system consists of a RFID reader unit and a receiver unit, and the location information of the material with the attached RFID tag is obtained by estimating the position of a RFID reader. The distance value for estimating the reader position is calculated using the Received Signal Strength Indicator (RSSI) value of Zigbee, and the performance evaluation of the proposed system is performed in the indoor space of $5m{\times}5m$.

Spin Test of 5 kWh Composite Flywheel Rotor (5 kWh 복합재 플라이휠 로터의 회전 시험)

  • Han, Hoon-Hee;Ha, Sung-Kyu;Kim, Jae-Hyuk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제11권9호
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    • pp.3135-3140
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    • 2010
  • A 5 kWh composite flywheel rotor was designed and manufactured, and its spin test was performed to monitor strain distribution and burst speed. Strain distribution in radial and circumferential directions of the rotor were measured using a wireless telemetry system based on bluetooth technology for real-time strain measurement. The strains was compared with pre-calculated design values to verify the initial rotor design. We noticed the rotor failed at 19,499 rpm in the spin test, 11 % lower than the predicted burst speed of 22,000 rpm. Failure occurred at the hub which connects the shaft and the composite rotor. The performance of the composite rotor was confirmed in a general sense, and the danger of unexpected failure of composite rotor during high-speed spinning was also demonstrated in this paper. Special attention should be paid to not only composite rotor but also hub when designing a flywheel energy storage system. The telemetry system needs to be further developed, especially enduring the high centrifugal forces, and can be used in a real time monitoring system for the flywheel energy storage system.

Development of Permanent Reference Electrode for Corrosion Monitoring of Underground Metallic Structures (지중 금속구조물 부식감시를 위한 영구매설용 기준전극 개발)

  • Ha, Y.C.;Bae, J.H.;Ha, T.H.;Lee, H.G.;Lee, J.D.;Kim, D.K.
    • Proceedings of the KIEE Conference
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.532-534
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    • 2004
  • The advancement of electronics and telecommunication technologies has forced the risk management system for underground metallic structures to evolve into the remote monitoring and control system. Especially, facilities such as gas pipelines, oil pipelines and water distribution lines might make hazardous effect on human safety without continuous monitoring and control. As a result, pipeline engineers have applied cathodic protection system to prevent the degradation of their facilities by corrosion and carried out a periodic monitoring of the pipe-to-soil (P/S) potentials at numberous test boxes along their pipelines. The latter action on a road in downtowns, however, is so much dangerous that the inspectors should be ready to suffer the threatening of their lives and maintenance. In order to minimize these social costs and hazards, a stand-alone type corrosion monitoring equipment which can be installed in test box, store the P/S data for given Belied and send the data by wired/wireless telecommunications is under development. In order to obtain the exact P/S data, however, a reference electrode should be located as close to the pipeline as possible. Actually, the measured potential by a conventional portable reference electrode contain inevitably an IR drop portion caused by the current flow from the cathodic protection rectifier or the subway railroad. To minimize this error, it is recommended that the reference electrode should be buried within 10 cm from the pipeline. In this paper, we describe the design parameters for fabricating the permanent type reference electrode and the characteristics of the developed reference electrode.

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Implementation of the wearable PTT measurement system for health monitoring during daily life (일상생활 건강 모니터링을 위한 착용형 PTT 측정 시스템의 구현)

  • Ye, Soo-Young;Noh, Yun-Hong;Jeong, Do-Un
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제15권1호
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    • pp.220-226
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    • 2011
  • Device of the ECG and pulse signal was made to measure PTT signal using non-invasive method and possible to wearable. PTT alterations were observed according to position change using implemented system.It was needed to ECG and pulse to detect the PTT, used the photoplethymorgraphy appeared to change the blood volume. And also wireless sensor node which was able to Zigbee compatibility was used to transfer the detected ECG and pulse signal to PC. Noise was removed from transit data and algorithm was applied to calculate the PTT. After the evaluation of both the conventional measuring systems and the proposed photoplethymography measuring system, a highly effective and efficient formation and distribution sequences were found within the proposed photoplethymography measuring system.

A Study of LMDS System Structure and Link Budget Analysis Against Output Power Variation of HUB Station In KOREA Environment (국내환경 LMDS 시스템의 구조와 기지국 출력 변화에 따른 링크버짓 분석)

  • Youm, Jee-Woon;Choi, Kwang-Joo;Oh, Sung-Hwan
    • Journal of the Korean Institute of Telematics and Electronics D
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    • 제36D권6호
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    • pp.1-12
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    • 1999
  • This paper illustrates and analyzes system structure, link budget and cell coverage to accommodate Korea environment about LMDS systems that are expected to play an important role as the future wireless infrastructure of the information superhighway. In the mean time, many parameters used for the analysis apply to the allocated frequency bandwidth (Up-stream : 24.25GHz-24.75GHz, Down-stream : 25.5GHz-27.5GHz) of Ministry of Information and Communication. The modem and channel coding must be developed to accommodate specifications of DAVIC protocol. The materials about atmospheric phenomena refer to apply specifications of ITU-R. This paper will be need to disign the network structure and system configuration of LMDS system.

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An Adaptive Storage System for Enhancing Data Reliability in Solar-powered Sensor Networks (태양 에너지 기반 센서 네트워크에서 데이터의 안정성을 향상시키기 위한 적응형 저장 시스템)

  • Noh, Dong-Kun
    • Journal of KIISE:Computer Systems and Theory
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    • 제36권5호
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    • pp.360-370
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    • 2009
  • Using solar power in wireless sensor networks requires a different approach to energy optimization from networks with battery-based nodes. Solar energy is an inexhaustible supply which can potentially allow a system to run forever, but there are several issues to be considered such as the uncertainty of energy supply and the constraint of rechargeable battery capacity. In this paper, we present SolarSS: a reliable storage system for solar-powered sensor networks, which provides a set of functions, in separate layers, such as sensory data collection, replication to prevent failure-induced data loss, and storage balancing to prevent depletion-induced data loss. SolarSS adapts the level of layers activated dynamically depending on solar energy availability, and provides an efficient resource allocation and data distribution scheme to minimize data loss.

Vehicle Location Data Generator based on a User (사용자 지정 시나리오에 기반한 차량 위치 데이터 생성기)

  • Jung Young-Jin;Cho Eun-Sun;Ryu Keun-Ho
    • Journal of the Korea Society of Computer and Information
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    • 제11권2호
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    • pp.101-110
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    • 2006
  • ADevelopment of various geographic observations, GPS, and Wireless Communication technologies make it easy to control many moving objects and to build an intelligent transport system and transport vehicle management system. However it is difficult to make a suitable system in the real world with a variety of tests to evaluate the performance fairly because real vehicle data are not enough as evaluating and testing the transport plan in the system. Therefore some moving object data generator would be used in most researches. However they can not generate vehicle trajectory according to a user scenario defined to be applied to transport plan, because the existing data generators consider only a gauss distribution, road network. In this paper we design and implement a vehicle data generator for creating vehicle trajectory data based on the user-defined scenario. The designed data generator could make the vehicle location depending on user's transport plan. Besides we store the scenario as patterns and reutilize the used scenario.

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