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Effect of Histamine on the production of Interleukin-1 from Macrophage-like Cell Line (Macrophage-like 세포로 부터 interleukin-1의 생성에 미치는 Histamine의 영향)

  • 오찬호;최동성
    • KSBB Journal
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    • v.5 no.2
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    • pp.113-118
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    • 1990
  • This experiment was carried out to investigate the immuno-regulatory effects of histamine on IL-1 synthesis and Ca2+ uptake in P388Dl macrophage-like cell line. The addition of histamine (10-8-10-3 M) increased IL-1 production in P388D1, cells, in a dose dependent manner, the treatment of EGTA (10-7-10-4M) and Co2+ ion (10-5-10-4M) decreased macrophage-derived IL-1 activity, and the pretreatment of histamine at the peak of 10-4M significantly enhanced Ca2+ uptake to P388Dl Cells. These results suggested that exogenous histamine was effective on IL-1 production from macrophage and the intracellular Ca2+ uptake play a important role in histamine-stimulated IL-1 synthesis.

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CSMA/CA based Transmission Scheme for QoS Assurance and Energy Efficiency of WPAN Systems (CSMA/CA 경쟁방식 기반의 WPAN 시스템을 위한 QoS 보장 및 에너지 효율적 전송방식)

  • Joo, Yang-Ick;Lee, Yeon-Woo;Jung, Min-A;Jang, Bong-Seog;Lee, Seong-Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.3B
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    • pp.135-143
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    • 2008
  • In this paper, we propose a QoS guaranteed and energy-efficient transmission scheme for Wireless Personal Area Networks (WPANs), which operate in conjunction with contention-based access protocols such as CSMA/CA. Energy consumption is one of the most important issues in WPAN systems, because WPAN devices are often required to operate under limited battery capacity. Furthermore, if the WPAN adopts a contention-based medium access protocol, the energy consumption problem becomes even more critical due to the collisions caused by independent channel access trials. Therefore, in this paper, we propose an algorithm that selects the optimum fragment size, modulation level, and transmission power, in order to minimize the energy consumption and guaranteethe QoS (Quality of Service) requirements, simultaneously. Our simulation results show that the proposed algorithm has better performance than the previous ones.

The Case Report of Degenerative Diseases of Knee Joint with Harpagophytum Radix Pharmacopuncture (천수근 약침을 이용한 퇴행성 슬관절질환 치험 1례)

  • Lee, Seung-Yeol;Kim, Hee-Jung;Bae, Sang-Eun;Kim, Heung-Su;Lee, Jin-Ho;Ha, In-Hyuck;Kim, Chul-Su
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.8 no.2
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    • pp.123-130
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    • 2013
  • Objectives : The purpose of this clinical case is to evaluate the efficacy of Harpagophytum radix. Pharmacopuncture on Degenerative diseases of knee joint. Methods : We used Korean Medicine treatment and Harpagophytum radix. pharmacopuncture, for this patients. This case is measured and assessed by Neumerical Rating Scale(NRS), Korea Western Ontario MacMaster Universities Osteoarthritis Index(KWOMAC) and Physical examination of knee joint. Results : The NRS decreased from 8 to 5(Left knee joint) & 5 to 4(Right knee joint) and KWOMAC total points decreased from 77 to 41. Also Physical examination of knee joint improved. Conclusions : Harpagophytum radix. pharmacopuncture with Korean Medicine treatment is proved to be helpful to the pain relief and function recovery of knee joint.

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Hybrid reservation request algorithm for dynamic reservation TDMA/TDD protocol (혼합 예약 요청 알고리즘을 이용한 동적 예약 TDMA/TDD 프로토콜)

  • 박선현;최덕규
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.05a
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    • pp.132-132
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    • 2001
  • 본 논문에서는 혼합예약요청(hybrid reservation request) 알고리즘을 적용한 새로운 동적 예약 TDMA 프로토콜을 제안한다. 제안된 혼합 예약 요청 알고리즘은 기존의 랜덤접속방식과 기지국의 중재 없이 단말간 직접 신호교환을 통하여 이웃 단말의 새로운 예약 요청을 대신 전송하는 방식을 혼합해서 사용하는 방법이다. 이 알고리즘은 기존 slotted-ALOHA 방식을 이용한 예약 요청의 비효율성을 개선하여 새로운 단말의 예약 요청실패로 인한 셀 전송지연 및 호 봉쇄 확률(call blocking probability)을 줄이기 위한 목적으로 제안되었다. 제안한 알고리즘은 새로 전송할 데이터를 가진 단말이 많은 경우에 특히 효율적이다. 본 논문에서 제안하는 프로토콜은 모든 종류의 트래픽이 예약을 통한 전송방식으로 전송된다. 즉, 단말들로부터의 예약 요청을 바탕으로, 기지국이 스케줄링을 하여 트래픽 별로 접근 슬랏을 할당해 주는 방식이다. 이 경우, 예약 요청을 하는 방법은 새로 전송을 개시하는 단말과 이미 전송중인 단말의 경우가 다른데, 새로운 전송을 위한 예약이 필요한 단말은 제안하는 알고리즘을 이용하며, 이미 예약에 성공한 단말은 기존에 사용하던 자신의 버스트헤더(burst header)에 피기백(piggybacking)하는 방법을 이용한다. 제안한 알고리즘에 따라, 새로 접속하는 단말이나 새로운 예약 요청이 필요한 단말은 두 단계로 요청을 전송할 수 있다. 첫 번째 단계는 이미 예약에 성공하여 전송중인 이웃단말에게 전송요청신호를 보내 간접적으로 기지국에게 예약을 요청하는 방법이며, 두 번째 단계는 첫 번째 방법이 실패했을 경우 기존의 랜덤접속방법에 참가하는 것이다 먼저 첫 번째 방법에서는 단말이 랜덤접근 구간의 예약요청구간(resonation request)중 하나의 미니 슬랏을 선택해 이웃 단말들에게 한번 방송(broadcast) 한다 이후 ACK 응답구간(ACK receive)에서 응답을 받으면 예약요청성공이라 간주하고, 그렇지 않으면 실패로 판단, 뒤이어 오는 랜덤접근구간(normal random access period)에 참가하여 기지국에게 직접 예약 요청을 한다. 시뮬레이션은 기존 slotted-ALOHA방식으로 랜덤 접속을 할 경우와 제안한 방식과의 성공률을 비교해 제안한 방식의 call blocking probability가 낮음을 보였다.

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A Dynamic Behavior Analysis of composite Few Plate Girder Railway Bridge under Variety of Track systems (소수주형 철도교의 궤도시스템 변화에 따른 동적거동 분석)

  • Lee Hong-Joon;Choi Jung-Youl;Eom Mac;Park Yong-Gul
    • Proceedings of the KSR Conference
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    • 2005.11a
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    • pp.1171-1176
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    • 2005
  • The latest technical development of steel plate girder railway bridge are developing in ways to maximize its durability of materials in use of high strength steel and efficiency of maintenance and management by the introduction of simplified and standardization ideas. In addition to this, it is also expected to reduce the cost of bridge construction and to simplify the process of bridge manufacturing. Referring to this, composite few plate girder railway bridge is highly recommendable that is very economical with the fine exterior. In this paper, it will analyse the variation of dynamic behavior of existing composite few plate girder railway bridge with ballast caused by modified Slab Track through interpretation of limited enzyme in order to obtain the existing data for improvement of Slab Track system from Ballast Track system. Consequently, it can help maximize economic efficiency and structural capability. As a results, although the natural frequency by modified Slab Track are decreased, it is hardly influencing on the safety of railway bridges. It is also evident in the case of slab deck with a reduced scale in comparison with Ballast Track. Therefore, it is expected to reduce the cost of a railway bridge plan. And, it can expect the synergistic effect of the ensure long term durability of bridge caused by decreased stresses of bottom flange due to reduced dead load. As a result, the analytical study are carried out to investigate the composite few plate girder railway bridge could be the optimal design method for the dynamic safety of a girder section.

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Numerical Simulation of Wave Breaking Near Ship Bow

  • Lee, Young-Gill;Kim, Nam-Chul;Yu, Jin-Won;Choi, Si-Young
    • Journal of Ship and Ocean Technology
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    • v.12 no.1
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    • pp.16-27
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    • 2008
  • The interaction between advancing ships and the waves generated by them plays important roles in wave resistances and ship motions. Wave breaking phenomena near the ship bow at different speeds are investigated both numerically and experimentally. Numerical simulations of free surface profiles near the fore bodies of ships are performed and visualized to grasp the general trend or the mechanism of wave breaking phenomena from moderate waves rather than concentrating on local chaotic irregularities as ship speeds increase. Navier-Stokes equations are differentiated based on the finite difference method. The Marker and Cell (MAC) Method and Marker-Density Method are employed, and they are compared for the description of free surface conditions associated with the governing equations. Extra effort has been directed toward the realization of extremely complex free surface conditions at wave breaking. For this purpose, the air-water interface is treated with marker density, which is used for two layer flows of fluids with different properties. Adaptation schemes and refinement of the numerical grid system are also used at local complex flows to improve the accuracy of the solutions. In addition to numerical simulations, various model tests are performed in a ship model towing tank. The results are compared with numerical calculations for verification and for realizing better, more efficient research performance. It is expected that the present research results regarding wave breaking and the geometry of the fore body of ship will facilitate better hull form design productivity at the preliminary ship design stage, especially in the case of small and fast ship design. Also, the obtained knowledge on the impact due to the interaction of breaking waves and an advancing hull surface is expected to be applicable to investigation of the ship bow slamming problem as a specific application.

Nutritional Management by Dietitian at Elderly Nursing Homes in Gyeonggi-do (경기도 일부 노인요양시설의 영양사 유무에 따른 영양관리 현황)

  • Yoon, Mi-Ock;Moon, Hyun-Kyung;Jeon, Ju-Young;Sohn, Cheong-Min
    • Journal of the Korean Dietetic Association
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    • v.19 no.4
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    • pp.400-415
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    • 2013
  • The purpose of the study was to examine the current status of nutritional management at elderly nursing homes. A survey was performed of 83 nursing homes from January 5, 2011 to January 21, 2011 via mail. A total of 34 nursing homes responded to the survey and 149 elderly subjects were analyzed according to the presence of a dietitian. Among the 34 nursing homes, 70.6% had a dietitian on duty. All of the facilities with a dietitian had the dietitian making the meal plan, whereas 70% of the facilities without dietitian served meals planned by a non-professional person. Overall, however, a low proportion of nursing homes implemented dietetic treatments for residents with diseases. For the nutritional assessment of these residents, a mini nutritional assessment (MNA) was performed. MNA scores were significantly associated with body mass index (BMI), mid-arm circumference (MAC), calf circumference (CC), ingestion problems, and weight loss during the last 3 months (P<0.001). Among the elderly studied, 5.4% were malnourished, and 36.9% were at risk for malnutrition by MNA score. The results of this survey show that the current management of nutrition at nursing homes is insufficient because the elderly who needed dietetic treatment did not receive proper care. Dietetic management is the most important service in all nursing homes. Therefore, to improve the nutritional status of elderly residents in nursing homes, systematic nutrition management by nutrition experts should be implemented.

A Study on an Efficient Routing Scheme for using a priority scheme in Wireless Sensor Networks (무선 센서 네트워크 환경에서 우선순위 기법을 이용한 효율적인 경로 설정에 대한 연구)

  • Won, Dae-Ho;Yang, Yeon-Mo
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.4
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    • pp.40-46
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    • 2011
  • Wireless Sensor Networks(WSNs) have shown a lot of good outcomes in providing a various functions depending on industrial expectations by deploying ad-hoc networking with helps of light loaded and battery powered sensor nodes. In particular, it is strongly requested to develop an algorithm of cross-layer control between 2-layer and 3-layer to deriver the sensing data from the end node to the sink node on time. In this paper, based on the above observation we have proposed an IEEE802.15.4 based self priority routing scheme under UC Berkely TinyOS platform. The proposed beacon based priority routing (BPR) algorithm scheme utilizes beacon periods in sending message with embedding the high priority data and thus provides high quality of service(QoS) in the given criteria. The performance measures are the packet Throughput, delivery, latency, total energy consumption. Simulation results under TinyOS Simulator(TOSSIM) have shown the proposed scheme outcome the conventional Ad hoc On-Demand Distance Vector(AODV) Routing.

Routing considering Channel Contention in Wireless Communication Networks with Multiple Radios and Multiple Channels (다수 라디오와 채널을 갖는 무선통신망에서 채널경쟁을 고려한 라우팅)

  • Ko, Sung-Won;Kang, Min-Su;Kang, Nam-Hi;Kim, Young-Han
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.5
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    • pp.7-15
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    • 2007
  • In wireless communication networks, single-radio single-channel architecture degrades throughput and end-to-end delay due to half-duplex transmission of wireless node and route intra interference. Also, In contention-based MAC (Medium Access Control) architecture, channel contention reduces throughput and packet collision enlarges end-to-end delay. In this paper, we use multi-radio multi-channel architecture which will make wireless node to operate in full duplex mode, and exclude route intra interference. Based on this architecture, we propose a new link metric, ccf which reflects the characteristics of a contention-based wireless link, and propose a routing path metric MCCR considering channel switching delay and route intra interference. MCCR is compared with MCR by simulation, the performance of a route established by MCCR outperforms the performance of a route by MCR in terms of throughput and end-to-end delay.

A Low Complex and Low Power Baseband IR-UWB Transceiver for Wireless Sensor Network (무선 센서 네트워크 응용을 위한 초광대역 임펄스 통신용 저복잡도, 저전력 베이스밴드 트랜시버)

  • Lee, Soon-Woo;Park, Young-Jin;Kang, Ji-Myung;Kim, Young-Hwa;Kim, Kwan-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.7
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    • pp.38-44
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    • 2008
  • In this paper, we introduce an low complexity and low power IR-UWB (impulse radio ultra wideband) baseband transceiver for wireless sensor network. The proposed baseband, implemented by TSMC 0.18um CMOS technology, has a simple structure in which a simplified packet structure and a digital synchronizer with 1-bit sampler to detect incoming pulses are used. Besides, clock gating method using gated clock cell as well as customized clock domain division can reduce the total power consumption drastically. As a result, the proposed baseband has about 23K digital gates with an internal memory of 2Kbytes and achieves about 1.8mW@1Mbps power consumption.