• Title/Summary/Keyword: Local Network

Search Result 2,883, Processing Time 0.036 seconds

DUAL BAND SLOT COUPLED MULTIPLE PATCH ANTENNA WITH BROAD BANDWIDTH AND HIGH DIRECTIVITY FOR WIRELESS ACCESS POINT (무선 액세스 포인트용 광대역의 고지향성 이중대역 슬롯 결합 다중 패치안테나)

  • Yeom, Insu;Kang, Seonghun;Jung, Changwon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.5
    • /
    • pp.3074-3078
    • /
    • 2014
  • We implemented a dual-band slot-coupled patch (SCP) antenna for the external access point (AP) of the wireless local area network (WLAN) band. The antennas consist of two radiators on three layers. The first radiator is a slotted bow tie antenna operating at the 2.4-2.483 GHz band. The second radiator is a patch antenna with parasitic elements operating at 4.095-5.845 GHz. The high gain and broad bandwidth is important element of wireless access. To enhance the bandwidth, a coupled feeding was used in the first radiator and a parasitic patch was used in the second radiator. We used a parasitic patch and chock to improve the directivity and isolation in both radiators. The porposed antenna was designed by EM simulation tool and measured. The S11 of the antenna was less than -11dB (VSWR 1.8:1) at operating frequency. The peak gain was more than 6 dBi in the first antenna and more than 8 dBi in the second antenna.

HVIA-GE: A Hardware Implementation of Virtual Interface Architecture Based On Gigabit Ethernet (HVIA-GE: 기가비트 이더넷에 기반한 Virtual Interface Architecture의 하드웨어 구현)

  • 박세진;정상화;윤인수
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.31 no.5_6
    • /
    • pp.371-378
    • /
    • 2004
  • This paper presents the implementation and performance of the HVIA-GE card, which is a hardware implementation of the Virtual Interface Architecture (VIA) based on Gigabit Ethernet. The HVIA-GE card is a 32-bit/33MHz PCI adapter containing an FPGA for the VIA protocol engine and a Gigabit Ethernet chip set to construct a high performance physical network. HVIA-GE performs virtual-to-physical address translation, Doorbell, and send/receive completion operations in hardware without kernel intervention. In particular, the Address Translation Table (ATT) is stored on the local memory of the HVIA-GE card, and the VIA protocol engine efficiently controls the address translation process by directly accessing the ATT. As a result, the communication overhead during send/receive transactions is greatly reduced. Our experimental results show the maximum bandwidth of 93.7MB/s and the minimum latency of 11.9${\mu}\textrm{s}$. In terms of minimum latency HVIA-GE performs 4.8 times and 9.9 times faster than M-VIA and TCP/IP, respectively, over Gigabit Ethernet. In addition, the maximum bandwidth of HVIA-GE is 50.4% and 65% higher than M-VIA and TCP/IP respectively.

Design and Implementation of the Digital Photo Frame based on Ubiquitous (유비쿼터스 기반 전자액자의 설계 및 구현)

  • Lee, Joa-Hyoung;Park, Chong-Myung;Heo, Nan-Sook;Jo, Young-Tae;Kwon, Young-Wan;Han, Woo-Ram;Seon, Ju-Ho;Kim, Jong-Wook;Yoo, Jae-Wook;Lee, Kang-Hee;Jung, In-Bum
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.12 no.9
    • /
    • pp.1703-1710
    • /
    • 2008
  • As the performance of digital camera keeps going on, the digital camera becomes into wide use recently so that the number of digital images taken by digital camera is increased rapidly. Given the augmentation of digital images, the digital photo frame has appeared for storing and enjoying the digital image and receives attention as the price of digital frame becomes down. However, users with the existing digital frame only could display the digital images and stream media stored in local disk. In the paper, we design and implement a new digital photo frame baled on ubiquitous which could provide a more variety of service to the user. With the proposed digital photo frame, the user could obtain the environment information and the digital image from multimedia sensor network. The users also could enjoy the various stream media stored in the remote streaming server seamlessly. In addition, the user could update the digital image through the web site at anywhere.

Efficient Multi-spot Monitoring System Using PTZ Camera and Wireless Sensor Network (PTZ 카메라와 무선 센서 네트워크를 이용한 효율적인 다중 지역 절전형 모니터링 시스템)

  • Seo, Dong-kyu;Son, Cheol-su;Yang, Su-yeong;Cho, Byung-lok;Kim, Won-jung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2009.10a
    • /
    • pp.581-584
    • /
    • 2009
  • Recently, the cameras which used for observation are installed in children protection area and local crime prevention area in order to protect life and property and by its work being recognized and are installed more. Normal cameras have cost problem to observe multiple area and detail, because they can observe only one place. PTZ camera can observe multiple area by moving focus by schedule or remote control, but it can't automatically move the focus of it to the place where event occurred, because it can't recognize the place. In this study, we can monitor multiple area effectively, by installing a wireless sensor node equipped with temperature, lighting, gas and human detection sensor to each area, to monitor many place low-price and actively and to move the focus of PTZ camera to preset position, and send recorded video to the user, when the various sensor data received from wireless sensors in observation area are to be determined abnormal by analyzing. In addition, at night we can record a scene using infrared, but to reduce power consumption of lighting system which are installed to improve resolution, it supplies power to the lighting system when event occurred. So we were able to implement low power green monitoring system.

  • PDF

Installation of Very Broadband Seismic Stations to Observe Seismic and Cryogenic Signals, Antarctica (남극 지진 및 빙권 신호 관측을 위한 초광대역 지진계 설치)

  • Lee, Won-Sang;Park, Yong-Cheol;Yun, Suk-Young;Seo, Ki-Weon;Yee, Tae-Gyu;Choe, Han-Jin;Yoon, Ho-Il;Chae, Nam-Yi
    • Geophysics and Geophysical Exploration
    • /
    • v.15 no.3
    • /
    • pp.144-149
    • /
    • 2012
  • Korea Polar Research Institute (KOPRI) has successfully installed two autonomous very broadband three-component seismic stations at the King George Island (KGI), Antarctica, during the 24th KOPRI Antarctic Summer Expedition (2010 ~ 2011). The seismic observation system is originally designed by the Incorporated Research Institutions for Seismology Program for Array Seismic Studies of the Continental Lithosphere Instrument Center, which is fully compatible with the Polar Earth Observing Network seismic system. The installation is to achieve the following major goals: 1. Monitoring local earthquakes and icequakes in and around the KGI, 2. Validating the robustness of seismic system operation under harsh environment. For further intensive studies, we plan to move and install them adding a couple more stations at ice shelf system, e.g., Larsen Ice Shelf System, Antarctica, in 2013 to figure out ice dynamics and physical interaction between lithosphere and cryosphere. In this article, we evaluate seismic station performance and characteristics by examining ambient noise, and provide operational system information such as frequency response and State-Of-Health information.

Assessment of the Effect of Geographic Factors and Rainfall on Erosion and Deposition (지형학적 인자 및 강우량에 따른 침식 및 퇴적의 영향 평가)

  • Yu, Wan-Sik;Lee, Gi-Ha;Jung, Kwan-Sue
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.11 no.2
    • /
    • pp.103-112
    • /
    • 2011
  • This study aims to demonstrate the relationship between various factors and soil erosion or deposition, simulated from distributed rainfall-sediment-runoff model applications. We selected area, overland flow length, local slope as catchment representative characteristics among many important geographic factors and also used the grid-based accumulated rainfall as a representative hydro-climatic factor to assess the effect of these two different types of factors on erosion and deposition. The study catchment was divided based on the Strahler's stream order method for analysis of the relationship between area and erosion or deposition. Both erosion and deposition increased linearly as the catchment area became larger. Erosion occurred widely throughout the catchment, whereas deposition was observed at the grid-cells near the channel network with short overland flow lengths and mild slopes. In addition, the relationship results between grid-based accumulated rainfall and soil erosion or deposition showed that erosion increased gradually as rainfall amount increased, whereas deposition responded irregularly to variations in rainfall. Within the context of these results, it can be concluded that deposition is closely related with the geographic factors used in this study while erosion is significantly affected by rainfall.

A Study on the Measurement of Knowledge Relatedness Density and Technological Complexity in South-east Region (동남권 지역의 지식 간 연관성 밀도와 기술 복합성 측정에 관한 연구)

  • Park, Gi-Woong;Kim, Donghyun
    • Journal of the Korean Regional Science Association
    • /
    • v.37 no.3
    • /
    • pp.3-18
    • /
    • 2021
  • The fourth Industrial Revolution is transforming the industrial structure of the region, and it is necessary to develop new industries and technologies that reflect regional characteristics. The purpose of this study is to measure the knowledge relatedness and technological complexity in Busan, Ulsan, and Gyeongnam, and to identify technologies with potential for regional industrial differentiation strategies. Using patent data from 2015 to 2019, co-occurrence matrices were derived from 652 IPC codes, and the knowledge relatedness density and technology complexity index were calculated. Network analysis was performed using the knowledge relatedness density. As a result of analysis, it was found that mechanical engineering occupied a large proportion, followed by chemistry and electrical engineering. As a result of applying the risk-benefit framework to derive technologies with the potential to differentiate local industries, the technological capabilities of low-risk-high-benefit were different. Among mechanical engineering, technologies such as engine, machine operation, and transportation were included in Busan. In Ulsan, environmental technology in chemical and materials, and heat treatment technology in mechanical engineering were technologies with low-risk and high-benefit capabilities. Gyeongnam showed competence in mechanical engineering, chemistry, and electrical engineering in some areas such as Gimhae, Yangsan, and Changwon. The results of this study are meaningful in that they identified technologies with potential for selecting and deriving strategic industries for regional growth based on latent knowledge in the region.

A Study on the Characteristics and Policy Demand of the Unmanned Vehicle Industry in Gyeonggi-do (경기도 무인이동체 산업 특성과 정책수요)

  • Kim, Myung Jin
    • Journal of the Economic Geographical Society of Korea
    • /
    • v.24 no.3
    • /
    • pp.283-299
    • /
    • 2021
  • As the intelligent revolution triggered by digital technology, unmanned vehicles such as self-driving cars, robots, and drones appeared, which brought about innovative changes in the industry. Gyeonggi Local government has established both an ordinance and a basic plan regarding unmanned vehicles. It is time to prepare a data-based policy by understanding the current state of the unmanned vehicle industry in the province. As a result of the survey, the unmanned vehicle industry in Gyeonggi Province is 25% of the nationwide, and more than 88% is concentrated in the southern part of Gyeonggi Province. The land sector such as the robot and autonomous vehicles are focused on 71.4% and the aviation sector such as drones are 26.7%. However, unmanned vehicle companies in Gyeonggi-do are mostly small-sized businesses with less than 10 years of experience and are in the stage of introduction and growth level. They have a plan to improve technology through continuous R&D by hiring human resources. Therefore, Gyeonggi-do needs to consider policy support for sustainable growth of start-up and small enterprises and for fostering professional manpower and technical skills as well as for establishing an unmanned vehicle industry network to create, share, and spread knowledge.

Risk Issue Analysis of Disaster Vulnerable Groups -Focusing on Cases of Children and Pregnant Women (재난취약계층의 위험이슈분석 -어린이, 임산부 사례를 중심으로-)

  • Kim, Shin Hye;Kwon, Seol A
    • The Journal of the Korea Contents Association
    • /
    • v.21 no.7
    • /
    • pp.291-303
    • /
    • 2021
  • In the modern society, the number of people in disaster vulnerable groups is rapidly increasing such as the elderly, the disabled, foreigners, and children. The common characteristics of the groups vulnerable to disasters are that they live in residence types that are exposed to disasters because they are impoverished and if they are exposed to disasters, recovery is a slow process. The purpose of this study is to identify the new risk issues by performing risk issue analysis on the targets of disaster vulnerable group and provide base data for the development of the policies. For the research method, this study centered on the cases of children and pregnant women out of the disaster vulnerable groups and focused on the issue data of social media throughout the past 10 years ('10~'19) and performed social network analysis. As a result, first, the development of the issue showed relevance in the occurrence of specific cases. Second, the awareness about the types, targets, and management method of crisis management was analyzed. Third, an analysis was performed on the sentiment words that considered the solution measures of risk issues or the characteristics of the targets and it was analyzed that there were word that triggered negative emotions. Therefore, it is anticipated for the base data to be used for the government and also for the local government to build an effective crisis management system of the rapidly changing disaster environment on the basis of the sentiment analysis performed on the people of the nation as well as public awareness.

The Internationalization of Korean Software-related New Venture on Resource Based Perspectives - The Bundle of Tangible and Intangible Resources - (자원기반관점에서의 한국 소프트웨어개발 벤처기업의 국제화 - 가시적 자원과 비가시적 자원의 조합을 중심으로 -)

  • Lee, Keun-Hee;Kim, Jung-Po
    • International Area Studies Review
    • /
    • v.13 no.2
    • /
    • pp.393-416
    • /
    • 2009
  • This paper explores the technology resource-based determinants influencing internationalization performance of Korean software-related new ventures. On the ground of the study by Zahra et al.(2003), this paper aims to test empirically in Korea how interaction effects of tangible and intangible technological resources, as firm capability, are related to software new ventures' internationalization performance. The test results shows that intangible technological resource represented by R&D intensity is not significantly related to internationalization performance, but reveals that intangible technological resource represented by strength of technological cooperation network and technological reputation is positively and significantly associated with internationalization performance. Internationalization performance is more significantly and positively associated with the interactions of tangible technological resource and intangible technological resource than those resources respectively. The implication for the findings in the paper is that cutting edge technological capability of software new ventures can be more closely associated with internationalization performance if those resources are fully utilized or leveraged by intangible resources acquired by cooperation with local networks and created through technological reputation of new ventures.