• Title/Summary/Keyword: rss

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A Study on Cooperative Based Location Estimation Algorithm in Wireless Sensor Networks (무선 센서 네트워크에서 상호 협력 기반 위치추정 알고리즘 연구)

  • Jeong, Seung-Heui;Lee, Hyun-Jae;Oh, Chang-Heon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.857-860
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    • 2008
  • In this paper, we proposed cooperative based localization algorithm for wireless sensor networks, which can estimate to unknown node position using received signal strength table set. The unknown nodes are monitor to RSS from neighbor nodes and exclude existence possibility area of sensor node in sensor field. Finally, we can calculate the centroid position for each unknown node with cooperative localization algorithm. Furthermore, these processes are applied iteratively about all nodes which is recorded to RSS table and can estimate for unknown nodes.

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A Received Signal Strength-based Primary User Localization Scheme for Cognitive Radio Sensor Networks Using Underlay Model-based Spectrum Access

  • Lee, Young-Doo;Koo, Insoo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.8
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    • pp.2663-2674
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    • 2014
  • For cognitive radio sensor networks (CRSNs) that use underlay-based spectrum access, the location of the primary user (PU) plays an important role in the power control of the secondary users (SUs), because the SUs must keep the minimum interference level required by the PU. Received signal strength (RSS)-based localization schemes provide low-cost implementation and low complexity, thus it is suitable for the PU localization in CRSNs. However, the RSS-based localization schemes have a high localization error because they use an inexact path loss exponent (PLE). Thus, applying a RSS-based localization scheme into the PU localization would cause a high interference to the PU. In order to reduce the localization error and improve the channel reuse rate, we propose a RSS-based PU localization scheme that uses distance calibration for CRSNs using underlay model-based spectrum access. Through the simulation results, it is shown that the proposed scheme can provide less localization error as well as more spectrum utilization than the RSS-based PU localization using the mean and the maximum likelihood calibration.

Performance Improvement of T-50 Fine Tracking Using Pilot Prefilter (조종사 필터에 의한 T-50 정밀추적 성능 향상)

  • Kim, Chong-Sup;Bae, Myung-Whan;Hwang, Byung-Moon;Koh, Gi-Oak;Kang, Cheul;Sung, Duck-Yong
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.625-630
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    • 2004
  • An advanced method of Relaxed Static Stability (RSS) is utilized for improving the aerodynamic performance of modern version supersonic jet fighter aircraft. The laws of flight control system utilize RSS criteria in both longitudinal and lateral-directional axes to achieve performance enhancements. Particularly, the design of longitudinal control laws for utilizing RSS methods greatly affects the performance of the aircraft in Air-to-Air Tracking and Air-to-Ground modes, which improves weapon delivery. In the area of Airto- Air Tracking, the development of longitudinal control laws aids in the fine tracking and gross acquisition of other aircraft. This paper proposes that Air-to-Air fine tracking can be improved via RSS control law design methods without effecting Air-to-Air gross acquisition.

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Experimental and Computational Studies of FSS-RSS Phenomena in an Over-Expanded Nozzle (과팽창 노즐 내에 발생하는 FSS-RSS 현상에 관한 실험적 및 수치해석적 연구)

  • Lee, Jong-Sung;Kim, Heuy-Dong
    • Journal of the Korean Society of Visualization
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    • v.8 no.3
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    • pp.56-62
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    • 2010
  • The interaction patterns between shock wave and boundary layer in a rocket nozzle are mainly classified into two categories, FSS(Free Shock Separation) and RSS(Restricted Shock Separation), both of which are associated with the thrust characteristics as well as side loads of the engine. According to the previous investigations, strong side loads of the engine are produced during the period of transition from FSS to RSS or vice versa. The present work aims at investigating the unsteady behavior of the separation shock waves in a two-dimensional supersonic nozzle, using experimental method and CFD. Schlieren optical method was employed to visualize the time-mean and time-dependent shock motions in the nozzle. The unsteady, compressible N-S equations with SST K-$\omega$ turbulence closure were solved using a fully implicit finite volume scheme. The results obtained show the separation shock motions during the transition of the interaction pattern.

Effects of Rice Straw (RS) on Allergic Contact Dermatitis (ACD) Induced by DNCB in Mice (볏집 도초(稻草)이 DNCB로 유발된 생쥐의 알레르기성 접촉성 피부염에 미치는 영향)

  • Park, Jem Ma;Chae, Joong Won
    • The Journal of Pediatrics of Korean Medicine
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    • v.27 no.4
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    • pp.39-49
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    • 2013
  • Objectives In the theory of Korean medicine, rice straw (RS) has been used effectively as treatments for dyspepsia, diarrhea, enteritis, inflammatory epigastric diseases and various dermatitis. However, the theory has not been studied intensively yet about anti-inflammatory effects for human. This study was to investigate effects of RS for a treatment of allergic contact dermatitis (ACD) induced by 2,4-dinitrochlorobezene (DNCB) in mice. Methods In this experiment, effects of RS were investigated on changes in body weights, dorsum skin thickness, clinical aspects on the dorsum skin, spleen and body weight among these four groups; normal group (NOR), control group (CON), RS spread group (RSS) and RS spread and administer group (RSS+Adm). In addition, the effects on proliferations of splenocytes were also investigated in vitro and in vivo study. Results RSS group and RSS+Adm group showed increasing in body weights, diminished dorsum skin thickness and treated dermatitis on dorsum skin. In RSS+Adm group, spleen weights were lowered significantly compared to CON group. Conclusions In conclusion, these data suggest that RS can decrease symptoms of ACD significantly, and it shows the anti-inflammatory and immunosuppressant effect as well. Therefore, RS can be useful to treat patients with ACD.

A Method to Improve Location Estimation of Sensor Node (센서노드 위치 측정 정확도 향상 방법)

  • Han, Hyeun-Jin;Kwon, Tae-Wook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12B
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    • pp.1491-1497
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    • 2009
  • Existing methods to measure are based on ToA (Timer of Arrival), RSS (Received Signal Strength), AoA(Angle of Arrival) and other methods. In this paper, we propose a compensation of ToA and RSS methods to measure more precisely the distance of nodes. The comparison experiments with the traditional ToA method show that the average error value of proposed method is reduced 30%. We believe that this proposal can improve location estimation of sensor nodes in wireless sensor networks.

RSS Service Method Using the User's Concerned Area and the QoS of Wireless Devices (사용자의 관심영역과 무선 단말기의 QoS를 고려한 RSS 서비스 방법)

  • Lee, Jong-Kap;Ryu, Dong-Yeop;Kong, Ran-Sook;Lim, Young-Hwan
    • The KIPS Transactions:PartC
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    • v.16C no.1
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    • pp.125-132
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    • 2009
  • The pre-generated web contents or various devices have to be used in order to execute UMA(UMA:Universal Multimedia Access). However, an HTLM web page for PC is not very compatible with wireless internet because of its unnecessary advertisements, high resolution, and various multimedia data. This is because the main focus when creating it was on high speed. In this paper indicates with the RSS channel, converted from the main part of the HTML web page, which users show interest in, a wireless compatible internet page can easily be created. Consequently, web administrators could create a wireless page easily and quickly, and wireless users would be able to find information in the same manner.

Realtime Adaptation Transcoding Service, supporting wireless mobile devices and RSS by using Web Structure Analysis (웹 컨텐츠의 구조 분석을 이용한 무선 단말기와 RSS로의 실시간 적응 변환 서비스)

  • Ryu Dong-Yeop;Han Seung-Hyun;Lim Young-Whan
    • Journal of the Korea Society of Computer and Information
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    • v.11 no.4 s.42
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    • pp.61-68
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    • 2006
  • As high speed Internet service technology develops. many people are accessing wireless internet service by using mobile devices. However. an HTLM web page for PC is not very compatible with wireless internet because of its unnecessary advertisements, high resolution. and various multimedia data. This is because the main focus when creating it was on high speed. As this research indicates with the RSS channel. converted from the main part of the HTLM web page, which users show interest in. a wireless compatibleinternet page can easily be created. Consequently, web administrators could create a wireless page easily and quickly, and wireless users would be able to find information in the same manner.

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On the Integrated process of RSS model and ISO / DIS 21448 (SOTIF) for securing autonomous vehicle safety (자율주행 자동차 안전성 확보를 위한 RSS 모델 및 ISO/DIS 21448 (SOTIF) 통합 프로세스 구축에 관한 선행연구)

  • Kim, Min Joong;Kim, Tong Hyun;Kim, Young Min
    • Journal of the Korean Society of Systems Engineering
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    • v.17 no.2
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    • pp.129-138
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    • 2021
  • Today, as the number of vehicles equipped with autonomous driving functions increases, the use of various sensors increases, and the complexity of system configuration increases. The ISO 26262 standard was published to prevent caused by systematic errors. Recently, the issue of external environmental factors rather than mechanical failure has increased. This issue is a problem outside of the scope of ISO 26262, and the ISO/DIS 21448 standard was published to solve this problem. Also, Mobileye proposed the RSS model that defined safe distance for dangerous situations in order to secure the safety of autonomous vehicles and who is responsible in case of an accident. In this paper, integrated process of ISO 21448 and RSS model, and through these results, we expect that possible to contribute to securing the safety and reliability of autonomous vehicles in the future.

Comparison of Anti-Inflammation Effects of Specimens Before and After the Oil Extraction of Raphanus sativus L. Seed in RAW 264.7 Macrophage Activated by LPS

  • Sunyoung Park;Dahyun Mun;Gunwoo Lee;Youngsun Kwon;Hye-yeon Kang;Jeom-Yong Kim
    • CELLMED
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    • v.13 no.6
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    • pp.7.1-7.6
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    • 2023
  • Raphanus sativus L. has been reported to have anti-inflammatory and anti-tumor activity. However, the anti-inflammatory effect and mechanism of action of the Raphanus sativus L. seeds (RSS) with or without oil are still unknown. This study was undertaken to investigate the in-vitro anti-inflammatory effect with or without oil in the RSS on RAW 264.7 cells stimulated by lipopolysaccharide (LPS). Results showed the suppressed LPS-induced secretion of pro-inflammatory mediators such as nitric oxide (NO), inflammatory cytokine (IL-6, TNF-α). Additionally, a decrease in protein expression of iNOS was observed, but nuclear translocation of NF-κB p65 was not inhibited. To elucidate the underlying mechanism of the anti-inflammatory effect of RSS, the involvement of mitogen-activated protein kinase (MAPK) signaling pathways was examined. We also found that RSS blocked LPS-induced phosphorylation of c-Jun N-terminal kinase/stress-activated protein kinase (JNK) signaling but did not affect the phosphorylation of p38 MAPK and extracellular signal-regulated kinase (ERK) 1/2. These results suggest that RSS may have potential as an anti-inflammatory agent through the inhibition of LPS-induced inflammatory cytokine production via regulation of the JNK pathway.