• 제목/요약/키워드: Isolated Nodes

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WSN Lifetime Analysis: Intelligent UAV and Arc Selection Algorithm for Energy Conservation in Isolated Wireless Sensor Networks

  • Perumal, P.Shunmuga;Uthariaraj, V.Rhymend;Christo, V.R.Elgin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권3호
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    • pp.901-920
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    • 2015
  • Wireless Sensor Networks (WSNs) are widely used in geographically isolated applications like military border area monitoring, battle field surveillance, forest fire detection systems, etc. Uninterrupted power supply is not possible in isolated locations and hence sensor nodes live on their own battery power. Localization of sensor nodes in isolated locations is important to identify the location of event for further actions. Existing localization algorithms consume more energy at sensor nodes for computation and communication thereby reduce the lifetime of entire WSNs. Existing approaches also suffer with less localization coverage and localization accuracy. The objective of the proposed work is to increase the lifetime of WSNs while increasing the localization coverage and localization accuracy. A novel intelligent unmanned aerial vehicle anchor node (IUAN) is proposed to reduce the communication cost at sensor nodes during localization. Further, the localization computation cost is reduced at each sensor node by the proposed intelligent arc selection (IAS) algorithm. IUANs construct the location-distance messages (LDMs) for sensor nodes deployed in isolated locations and reach the Control Station (CS). Further, the CS aggregates the LDMs from different IUANs and computes the position of sensor nodes using IAS algorithm. The life time of WSN is analyzed in this paper to prove the efficiency of the proposed localization approach. The proposed localization approach considerably extends the lifetime of WSNs, localization coverage and localization accuracy in isolated environments.

무선센서네트워크에서 에너지 효율을 위한 혼합적 라우팅 프로토콜 (Hybrid Routing protocol for Energy Efficiency in Wireless Sensor Networks)

  • 김진수
    • 디지털융복합연구
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    • 제10권9호
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    • pp.363-368
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    • 2012
  • 클러스터 기반의 라우팅 프로토콜은 네트워크 내의 노드들의 에너지를 균등하게 소비하나 고립 노드가 발생하여 에너지 효율을 저해하며, 홉 기반의 라우팅 프로토콜은 대규모 네트워크나 동적으로 변경되는 환경에는 적당하나, 정기적인 플러딩과 싱크 주변 노드들의 급격한 에너지 손실로 인해 네트워크 생존 시간을 줄어들게 한다. 따라서 본 논문에서는 무선 센서 네트워크 내의 노드들의 제한된 에너지 자원을 균등하게 소모하기 위해 클러스터링 기반의 라우팅 방법을 사용하고 클러스터에 포함되지 않은 고립 노드들을 근접 클러스터에 홉 방식을 적용하였다. 참여 못한 고립 노드들을 클러스터에 포함시킬 때 노드들의 에너지 부하를 균등하게 하기 위해 피보나치수열을 이용하여 클러스터에 참여하는 노드 수를 조절하였다. 본 논문에서 제안한 프로토콜이 기존의 방법에 비해 고립 노드의 수를 줄여 에너지 효율이 높아짐을 보였다.

Improved Detection of Metastases by Step Sectioning and Immuno-Histochemical Staining of Axillary Sentinel Nodes in Patients with Breast Carcinoma

  • Ensani, Fereshteh;Enayati, Ladan;Rajabiani, Afsaneh;Omranipour, Ramesh;Alavi, Nasrinalsadat;Mosahebi, Sara
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권10호
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    • pp.5731-5734
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    • 2013
  • Background: The object of this study was to examine whether a new protocol including step-sectioning and immunohistochemistry (IHC) staining of axillary sentinel nodes (SN) would lead to detection of more metastases in patients with breast cancer. Materials and Methods: Sixty-nine tumor free sentinel lymph nodes were examined. Step frozen sectioning was performed on formalin fixed SN and stained both by hematoxylin and eosin (H and E) and cytokeratin markers using IHC. Any tumoral cell in IHC stained slides were considered as a positive result. Metastases up to 0.2 mm were considered as isolated tumor cells and 0.2 up to 2 mm as micrometastasis. Results: Mean age of the patients was $48.7{\pm}12.2$ years. Step sectioning of the SN revealed 11 involved by metastasis which was statistically significant (p<0.001). Furthermore, 15 (21.7%) of the patients revealed positive results in IHC staining for pan-CK marker and this was also statistically significant (p=0.001). Ten patients had tumoral involvement in lymph nodes harvested from axillary dissection and 4 out of 15 lymph nodes with positive result for CK marker were isolated tumor cells. However, 4 of 10 patients with tumor positive lymph nodes in axillary dissection were negative for CK marker and in contrast 6 of the pan-CK positive SN were in patients with tumor-free axillary lymph nodes. Conclusions: Both IHC and step sectioning improve the detection rate of metastases. Considering the similar power of these two methods, we recommend using either IHC staining or step sectioning for better evaluation of harvested SNs.

대구시(大邱市) 도축장(屠畜場)에서 처리(處理)된 돼지의 Salmonella 속균(屬菌)의 보균상태(保菌狀態) (Carriage of Salmonella in Pigs Slaughtered at Daegu Slaughter-house)

  • 탁련빈
    • 대한수의학회지
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    • 제18권1호
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    • pp.15-18
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    • 1978
  • Ten strains of Salmonella were isolated from feces and lymph nodes of swine slaughtered at Daegu slaughter-house and the rate of isolation was 6.0 percent. Nine strains of Salmonella were isolated by enrichment in selenite F broth and one strain by direct culture on SS agar, but none of Salmonella were isolated from MacConkey ager and in SS broth. Among Salmonella isolated, Salmonella typhimurium occupied over half (6 strains) and the importance of Salmonella in swine for the incidence of food poisoning in man was discussed.

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The Security DV-Hop Algorithm against Multiple-Wormhole-Node-Link in WSN

  • Li, Jianpo;Wang, Dong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권4호
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    • pp.2223-2242
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    • 2019
  • Distance Vector-Hop (DV-Hop) algorithm is widely used in node localization. It often suffers the wormhole attack. The current researches focus on Double-Wormhole-Node-Link (DWNL) and have limited attention to Multi-Wormhole-Node-Link (MWNL). In this paper, we propose a security DV-Hop algorithm (AMLDV-Hop) to resist MWNL. Firstly, the algorithm establishes the Neighbor List (NL) in initialization phase. It uses the NL to find the suspect beacon nodes and then find the actually attacked beacon nodes by calculating the distances to other beacon nodes. The attacked beacon nodes generate and broadcast the conflict sets to distinguish the different wormhole areas. The unknown nodes take the marked beacon nodes as references and mark themselves with different numbers in the first-round marking. If the unknown nodes fail to mark themselves, they will take the marked unknown nodes as references to mark themselves in the second-round marking. The unknown nodes that still fail to be marked are semi-isolated. The results indicate that the localization error of proposed AMLDV-Hop algorithm has 112.3%, 10.2%, 41.7%, 6.9% reduction compared to the attacked DV-Hop algorithm, the Label-based DV-Hop (LBDV-Hop), the Secure Neighbor Discovery Based DV-Hop (NDDV-Hop), and the Against Wormhole DV-Hop (AWDV-Hop) algorithm.

돈군의 Salmonella 모니터링을 위한 림프절 추출액 사용에 대한 평가 (Evaluation of the extract from lymph nodes for Salmonella monitoring in pig herds)

  • 정병열;추지훈;김지훈;정재윤
    • 대한수의학회지
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    • 제46권2호
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    • pp.119-125
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    • 2006
  • The objective of this study was to investigate the use of extract from mesenteric lymph nodes as an alternative to serum for ELISA to detect Salmonella antibodies in slaughter pigs. Among 324 slaughter pigs, 65 (20.1 %) were positive in the serum ELISA and 76 (23.5%) were positive in the ELISA with extract from lymph nodes. A total of 24 (7.4%) Salmonella representing 6 serotypes were isolated from mesenteric lymph nodes and 35 (10.8%) Salmonella belonging to 2 serotypes were also recovered from cecal contents of slaughter pig samples, respectively. The most prevalent serogroup was B (55.9% of isolates) and serotype was Typhimurium (52.5% of isolates). In the comparison of the results of between the serum ELISA and Salmonella isolation, kappa value was 0.28 with mesenteric lymph nodes and 0.37 with cecal contents, respectively. However, the extract ELISA had sensitivity of 98.5%, specificity of 95.4% and kappa value of 0.88 as compared with the serum ELISA. Because high degree of concordance between the serum ELISA and the extract ELISA was observed (P=0.24), extract from lymph nodes could be used as an alternative to serum for the detection of Salmonella antibodies in the ELISA.

Expression of IgG1 Germline Transcripts in Germinal Center B Cells of Mouse Popliteal Lymph Nodes

  • Lee, In-Woo;Kim, Jin-Ho;Chung, Gook-Hyun
    • BMB Reports
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    • 제29권2호
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    • pp.127-132
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    • 1996
  • Germinal centers (GCs) are formed in peripheral lymphoid tissues in response to protein antigens. In order to see if immunoglobulin isotype switching takes place in GC B-cells, we isolated GC B-cells (PNA positive cells) from mouse popliteal lymph nodes by a flow cytometer after the staining of lymph node cells with PNA-FITC and anti-B220-PE, and determined the expression of ${\gamma}1$ germline transcript and ${\gamma}1$ mRNA by RT-PCR. ${\gamma}1$ germline transcript and ${\gamma}1$ mRNA were amplified specifically in cDNAs from hybridoma expressing IgG1 or splenocytes stimulated LPS plus IL-4. Germinal center B-cells formed in popliteal lymph nodes of mice immunized with chicken ovalbumin were isolated 7 days after immunization. We sorted GC B-cells five times. Immunoglobulin ${\gamma}1$ germline transcripts were expressed in germinal center B-cells in three out of five sorts whereas two out of five sorts did not express ${\gamma}1$ germline transcripts in GC B-cells. The contents of GC B-cells ranged from 5 to 7% of total lymph node cells in most flow cytometric analyses but those of two sorted cells which did not express ${\gamma}1$ germline transcripts were out of normal range. These results imply that isotype switching of immunoglobulins may take place in GCs.

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다층퍼셉트론의 성능향상을 위한 출력노드 수 증가 (Increasing Output Nodes for Performance Improvement of Multilayer Perceptrons)

  • 오상훈
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2006년도 추계 종합학술대회 논문집
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    • pp.13-15
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    • 2006
  • 다층퍼셉트론을 패턴인식 문제에 적용하는 경우 대부분 하나의 클래스 당 하나의 출력노드를 할당한다. 이 논문에서는 class 당 출력노드 수를 증가시키는 경우에 다층퍼셉트론의 성능이 향상되는 지 고립단어 인식 문제의 시뮬레이션을 통하여 고찰하였다. 시뮬레이션 결과 출력노드 수가 하나인 경우보다 증가시킨 경우 더 나은 성능을 얻었다.

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Location-based Support Multi-path Multi-rate Routing for Grid Mesh Networks

  • Hieu, Cao Trong;Hong, Choong Seon
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2009년도 춘계학술발표대회
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    • pp.1264-1266
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    • 2009
  • We introduce a location-based routing model applied for grid backbone nodes in wireless mesh network. The number of paths with nearest distance between two nodes is calculated and used as key parameter to execute routing algorithm. Node will increase the transmission range that makes a trade off with data rate to reach its neighbors when node itself is isolated. The routing model is lightweight and oriented thanks to the simple but efficient routing algorithm.

An Efficient Energy Charging Scheme for Wireless Sensor Networks Using a Mobile Sink Capable of Wireless Power Transmission

  • Park, Kyoung nam;Yoon, Ikjune
    • 한국컴퓨터정보학회논문지
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    • 제24권5호
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    • pp.1-9
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    • 2019
  • In this paper, we propose the algorithms which determine 1) the efficient anchor-node visiting route of mobile sink in terms of energy supply and 2) the efficient energy amount to be charged to each anchor node, by using the information of each anchor node and the mobile sink. Wireless sensor networks (WSNs) using mobile sinks can be deployed in more challenging environments such as those that are isolated or dangerous, and can also achieve a balanced energy consumption among sensors which leads to prolong the network lifetime. Most mobile sinks visit only some anchor nodes which store the data collected by the nearby sensor nodes because of their limited energy. The problem of these schemes is that the lifetime of the anchor nodes can be shorten due to the increased energy consumption, which rapidly reduces the overall lifetime of WSN. This study utilizes a mobile sink capable of wireless power transmission to solve this problem, so a mobile sink can gather data from anchor nodes while charging energy to them. Through the performance verification, it is confirmed that the number of blackout nodes and the amount of collected data are greatly improved regardless of the size of the network.