• Title/Summary/Keyword: B-MAC

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Authenticated IPv4 Address Allocation Using Human Recognition in DSTM Server (Human Recognition 방법을 적용한 DSTM 서버의 IPv4 주소 할당 인증 방법)

  • Choi, Jae-Duck;Kim, Young-Han;Kwon, Taek-Jung;Jung, Sou-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.11B
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    • pp.979-986
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    • 2006
  • DSTM is one of the 1Pv6/IPv4 transition mechanisms using IPv4-in-IPv6 tunneling for communication between IPv6 node with dual stack and Ipv4-only node. In DSTM, the DSTM server using the DHCPv6 is vulnerable to DoS attacks which can exhaust the IPv4 address pool. In this paper, an authentication model using a HRAA (Human Recognition Address Allocation) scheme was proposed to protect DHCP server against DoS attacks. The proposed authentication model in DSTM that uses an image file for verification is effective because only human can respond to the challenge for authenticated address allocation. The proposed model can be used anytime and anywhere in a DSTM domain, and is secure against DoS attacks.

Effects of Nelumbo nucifera on the Regional Cerebral Blood Flow and Blood Pressure in Rats (연근의 열수 추출물이 흰쥐의 국소 뇌혈류량과 혈압에 미치는 영향)

  • Park Sung-Hye;Sihn Eon-Hwan;Koo Jae-Geun;Lee Tae-Hun;Han Jong-Hyun
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.1
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    • pp.49-56
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    • 2005
  • The purpose of this study was to measure the changes of regional cerebral blood flow(rCBF) and blood pressure(BP) in rats, following the intravenous injection of Nelumbo nucifera water extract. The measurement was continually monitored by laser-doppler flowmeter and pressure transducer in anesthetized adult Sprague-Dawley rats for about 2 to 2 and half hours through the data acquisition system composed of MacLab and Macintosh computer. The results of this experiment were as follows. Nelumbo nucifera significantly increased the changes of rCBF in rats. The rCBF of Nelumbo nucifera was not changed by pretreated propranolol, atropine, L-NNA and indomethacin. But the rCBF of Nelumbo nucifera was decreased by pretreated methylene blue. Nelumbo nucifera decreased the BP significantly. The BP of Nelumbo nucifera was not changed by pretreated propranolol, atropine, L-NNA and indomethacin. But the BP of Nelumbo nucifera was decreased by pretreated methylene blue. These results indicated that Nelumbo nucifera might increase the rCBF and decrease the BP which related to guanylyl cyclase activity.

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Priority Collision Resolution Algorithm on HFC Networks (우선 순위를 고려한 HFC 망의 충돌 해소 알고리즘)

  • 김변곤;박준성;정경택;전병실
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.7B
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    • pp.1252-1260
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    • 1999
  • The HFC network has a architecture of a star topology in fiber optic trunks, and tree and branch topology is used in the part of coaxial cable. It is well known that the HFC upstream channel is noisy. Ingress, common mode distortion and impulse noise exist in the upstream channel. In order to provide Quality of Service(QoS) to users with real-time data such as voice, video and interactive services, the evolving IEEE 802.14 standard for HFC networks must include an effective priority scheme. The scheme separates and resolves collisions between stations in a priority order. It is important to simulate protocols under a practical environment. The proposed algorithm in this paper is simulated with the assumption that the collision detector made certain mistake due to noises. Simulation results show that the proposed algorithm is more efficient than existing tree-based algorithm under practical environment.

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Power Consumption Analysis of Sensor Node According to Beacon Signal Interval in IEEE 802.15.4 Wireless Star Sensor Network (IEEE 802.15.4 무선 스타 센서 네트워크에서 비콘 신호 주기에 따른 센서 노드 전력소모량 분석)

  • Yoo Young-Dae;Choi Jung-Han;Kim Nam
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.9B
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    • pp.811-820
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    • 2006
  • In this paper, The correlation of the power consumption of sensor node is analyzed according to the analyze parameter in IEEE 802.15.4 star sensor network. And It is studied the influence on analysis parameter. The power consumption of sensor network in transmission process and average transmission power consumption drives to numerical formula. And CSEM WiseNET system measurement value is used. As a simulation result, The power consumption of sensor node in star network consist of 10 sensor nodes is more than 20 % that in single network in average. When beacon signal interval is 0.1 second in all frequency bands, the power consumption of sensor node in up-link is more than 2.5 times that in down-link in average. When beacon signal interval is 1 second and the number of sensor nodes increases to 100 and sensing data increases to 100 byte, the power consumption of sensor node increases to 2.3 times. And The superior performance of 2.4 GHz frequency band has than 868/915 MHz frequency band up to $6{\sim}12$ times.

Extraction of Computer Image Analysis Information by Desk Top Computer from Beef Carcass Cross Sections

  • Karnuah, A.B.;Moriya, K.;Sasaki, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.8
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    • pp.1171-1176
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    • 1999
  • The precision and reliability of the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section scans was evaluated by the repeatability (R) and coefficient of variation (CV) for error variance. The 6th and 7th ribs cross section of carcasses from 55 fattened Japanese Black steers were used. The image analysis was conducted using a desk top computer (Macintosh-Apple Vision 1710 Display) connected to a scanner and an image capture camera. Two software applications, Adobe Photoshop and Mac Scope were used interchangeably. The information extracted and measured were individual muscle area, circumference length, long and short axes lengths, muscle direction; distance between any two muscle centers of gravity; cross section total area, lean, fat, and bone. The information was extracted after the processes of scanning, digitization, masking, muscle separation, and binarization. When using the Computer Image Analysis technique by desk top computer, proper digitization and selection of scanning resolution are very important in order to obtain accurate information. The R-values for muscle area, circumference, long and axes lengths, and direction ranged from 0.95 to 0.99, whereas those of the distance between any two muscle centers of gravity ranged from 0.96 to 0.99, respectively. For the cross section total area, lean, fat, and bone it ranged from 0.83 to 0.99. Excellent repeatability measurements were observed for muscle direction and distance between any two muscle centers of gravity. The results indicate that the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section is reliable and has high precision.

The Study of Sensor Network for Information Retrieval and Communication Protocol High Performance Algorithm (센서 네트워크의 정보검색 및 통신프로토콜 성능향상 알고리즘에 관한 연구)

  • Kang, Jeong-Yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.5B
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    • pp.816-823
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    • 2010
  • Recently research efforts for ubiquitous technology that includes RFID(Radio Frequency Deification and sensor networks are conducted very actively The architectural framework of the USN sensor network discovery service. The survey of the USN technology is conducted on four technological visions that contain USN system technology USN networking technology and USN middleware along with the service platform, With respect to each technological division domestic and worldwide leading research projects are primarily explored with their technical features and research projects are primarily explored with their technical features and research outputs. Boasted on the result of the survey we establish a USN software model that includes data sensing, sensor data storage sensor data storage sensor data naming and sensor feed name service. This main objective of this model is to provide a reference model for the facilitation of USN application developments.

Dynamic Allocation of Channel Times based on Link Quality of HR-WPAN (HR-WPAN에서 링크 상태에 따른 동적 채널 타임 할당 기법)

  • Kang, Jae-Eun;Byun, Sung-Won;Lee, Jong-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.3B
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    • pp.264-273
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    • 2009
  • For IEEE 802.15.3 HR-WPAN, we propose the DABL algorithm that PNC can allocate the channel times to the DEV in super frame in order that system frame throughput is increased and the delay is decreased. In detail, the DABL algorithm allows to dynamically allocate channel time as well as to adaptively apply the modulation and coding scheme based on the link quality of the DEV. In addition, due to the facts that QoS is quite different depending on service types, we provide the DABL algorithm taking into account RT(Real Time) traffic and Non-RT traffic respectively. Finally, we show simulation results of the DABL algorithm compared to the conventional algorithm that the PNC equally allocates channel times to the DEV regardless of the link quality of the DEV.

Communication Event-driven Power Management for Energy Efficient Wireless Sensor Network (에너지 효율적인 무선 센서 네트워크를 위한 통신 이벤트 기반의 전력 관리 방안에 관한 연구)

  • Hwang, Kwang-Il
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.7B
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    • pp.411-421
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    • 2007
  • It is well known that the biggest problem of wireless sensor networks is power conservation. There have been two major approaches to efficiently use energy in wireless sensor networks. One is to use a dynamic power management scheme and the other is to use energy efficient protocols. In the former, the power manager is responsible for managing the proper power state of CPU and each I/O with respect to the events, but the power manager does not concern about the internal operation of the underlying network protocols. Thus such conventional power managers can waste unpredicted power during communication period. On the other hand, the energy efficient protocols are just focused on the power saving operation of the radio PHY. In this paper, we introduce an energy-efficient power saving mechanism that can significantly reduce unwanted power consumption of wireless sensor nodes through the communication event-driven power management. We show that our scheme improves the energy conservation in the entire network through simulations.

A Study on Manufacturing System Integration with a 3D printer based on the Cloud Network (클라우드 기반 3D 프린팅 활용 생산 시스템 통합 연구)

  • Kim, Chi-yen;Espaline, David;MacDonald, Eric;Wicker, Ryan B.;Kim, Da-Hye;Sung, Ji-Hyun;Lee, Jae-Wook
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.3
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    • pp.15-20
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    • 2015
  • After the US government declared 3D printing technology a next-generation manufacturing technology, there have been many practical studies conducted to expand 3D printing technology to manufacturing technologies, called AMERICA MAKES. In particular, the Keck Center, located at the University of Texas at El Paso, has studied techniques for easily combing the 3D stacking process with space mobility and expanded these techniques to simultaneous staking techniques for multiple materials. Additionally, it developed convergence manufacturing techniques, such as direct inking techniques, in order to produce a module structure that combines electronic circuits and components, such as CUBESET. However, in these studies, it is impossible to develop a unified system using traditional independent through simple sequencing connections. This is because there are many problems in the integration between the stacking modeling of 3D printers and post-machining, such as thermal deformations, the precision accuracy of 3D printers, and independently driven coordinate problems among process systems. Therefore, in this paper, the integration method is suggested, which combines these 3D printers and subsequent machining process systems through an Internet-based cloud. Additionally, the sequential integrated system of a 3D printer, an NC milling machine, machine vision, and direct inking are realized.

Effects of Various Calcium Powders as Replacers for Synthetic Phosphate on the Quality Properties of Ground Pork Meat Products

  • Bae, Su Min;Cho, Min Guk;Jeong, Jong Youn
    • Food Science of Animal Resources
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    • v.37 no.3
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    • pp.456-463
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    • 2017
  • The aim of this study was to identify the optimal and superior type of natural calcium for replacing phosphate in cooked ground pork products. To achieve this, 0.5% eggshell calcium (ESC), oyster shell calcium (OSC), marine algae calcium (MAC), or milk calcium (MC) was added to ground pork meat products. The effect of this substitution was studied by comparing the substituted products with products containing 0.3% phosphate blend (control). ESC was considered an ideal phosphate replacer for minimizing the cooking loss, which likely resulted from the increase in the pH of the product. Among the other natural calcium types, OSC treatment did not cause a significant increase in pH, but it lowered the cooking loss. CIE $L^*$ values were higher (p<0.05) in products treated with OSC or MC than the control, and lowest (p<0.05) in the products with ESC. However, products with ESC had higher (p<0.05) CIE $a^*$ and CIE $b^*$ values than the control and products treated with other powders. Compared to the control, products treated with ESC and OSC had similar substitution effects on the textural properties of the products. Therefore, the results of this study suggested that the combined use of ESC and OSC could be a potentially effective method for replacing synthetic phosphate in ground pork products.