• 제목/요약/키워드: node importance

검색결과 127건 처리시간 0.027초

On Location Security Solutions in Vehicular Ad Hoc Networks

  • Hussain, Rasheed;Son, Junggab;Oh, Heekuck
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2012년도 추계학술발표대회
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    • pp.1053-1056
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    • 2012
  • Location information is considered to be of prime importance in Vehicular Ad Hoc NETworks (VANETs) because important decisions are made based on accurate and sound location information. Vehicles exchange their whereabouts in the form of scheduled beacon messages with their neighbors. These messages contain location, speed, time, and lane information etc. In this paper we aim at the location security in VANET and emphasize on the confidentiality and integrity of location information in case of Nonline-of-Sight (NLoS). For location confidentiality we propose a geolock-based mechanism whereas for location integrity we leverage cooperation among neighbors. In case of NLoS, the verifier vehicle asks its one-hop neighbors in an efficient way to verify the claimed location of the node on his behalf. On the basis of trust values and weightage assigned to neighbors, it is decided whether the verification is sound.

A novel approach for designing of variability aware low-power logic gates

  • Sharma, Vijay Kumar
    • ETRI Journal
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    • 제44권3호
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    • pp.491-503
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    • 2022
  • Metal-oxide-semiconductor field-effect transistors (MOSFETs) are continuously scaling down in the nanoscale region to improve the functionality of integrated circuits. The scaling down of MOSFET devices causes short-channel effects in the nanoscale region. In nanoscale region, leakage current components are increasing, resulting in substantial power dissipation. Very large-scale integration designers are constantly exploring different effective methods of mitigating the power dissipation. In this study, a transistor-level input-controlled stacking (ICS) approach is proposed for minimizing significant power dissipation. A low-power ICS approach is extensively discussed to verify its importance in low-power applications. Circuit reliability is monitored for process and voltage and temperature variations. The ICS approach is designed and simulated using Cadence's tools and compared with existing low-power and high-speed techniques at a 22-nm technology node. The ICS approach decreases power dissipation by 84.95% at a cost of 5.89 times increase in propagation delay, and improves energy dissipation reliability by 82.54% compared with conventional circuit for a ring oscillator comprising 5-inverters.

센서 네트워크 환경에서 최적화된 분산 R-tree를 이용한 에너지 인식 질의 처리 방법 (Power-Aware Query Processing Using Optimized Distributed R-tree in Sensor Networks)

  • 수라즈반데;어상훈;김호석;배해영
    • 정보처리학회논문지D
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    • 제13D권1호
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    • pp.23-28
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    • 2006
  • 본 논문에서는 센서 네트워크 환경에서 최적화된 분산 R-tree를 사용하여 공간 범위 질의 처리시 센서들의 에너지 소모를 최소화하는 방법을 제안한다. 제안된 기법은 센서 네트워크를 이용하는 공간 범위 질의 처리시 센서들의 공간상의 위치에 대한 색인을 이용하는 새로운 방법이다. 최근들어 센서 네트워크 환경에서의 공간 범위 질의는 특정 지역에 대한 센서 노드들의 집계 값을 계산하는 방법으로 더욱 중요시되어지고 있다. 기존 연구들은 공간 범위 질의 처리의 중요성을 많이 언급을 하였지만 현재까지 이에 대한 효율적인 방법에 대해서는 제안하지 못하고 있는 실정이다. 제안된 기법에서 센서 네트워크 상의 각각의 센서 노드들은 자신과 자신의 자식 노드들의 위치를 포함하는 MBR을 갖는다. 공간 범위 질의는 제안하는 분산 R-tree를 기반으로 센서들의 공간상의 위치와 질의 범위가 서로 겹치는 지역에 대하여 평가된다. 이러한 접근방법은 공간 범위 질의에 대한 평가를 수행함에 있어 참여하지 않는 불필요한 노드들과의 통신을 방지하여 센서 노드들의 에너지 소모를 최소화한다.

도합유사도를 이용한 한국어 문서요약 시스템 (A Korean Text Summarization System Using Aggregate Similarity)

  • 김재훈;김준홍
    • 인지과학
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    • 제12권1_2호
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    • pp.35-42
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    • 2001
  • 본 논문에서 문서는 문서관계도라고 하는 가중치 그래프로 표현된다. 노드는 문서의 구성요소인 문장을 명사벡터로 표현하고, 링크는 노드들 간의 의미적인 관계를 표현하며 의미적 유사도를 가중치로 가지고 있다. 한 노드의 인접한 노드를 사이의 유사도 합을 도합유사도라고 하며, 이를 문서에서 문장의 중요도로 간주한다. 본 논문에서는도합유사도를 이용한 한국어 문서요약 시스템을 기술한다. 실험에 사용된 평가용 요약문서는 정보처리관련 분야에서 수집된 논문 100편과 KORDIC에서 구축한 신문기사 105건을 이용하였다. 문서요약 시스템에 의해서 생상된 요약문서와 크기가 본문의 20%이고 평가용 요약문서가 논문(서론과 결론)일 경우, 재현율과 정확률은 각각 46.6%와 76.9%를 보였으며, 또한 평가용 요약문서가 신문기사일 경우, 재현율과 정확률은 각각 30.5%과 42.3%를 보였다.

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인공지능 학습을 위한 웹 컴파일러 설계 및 구현 (Design and Implementation of Web Compiler for Learning of Artificial Intelligence)

  • 박진태;김현국;문일영
    • 한국항행학회논문지
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    • 제21권6호
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    • pp.674-679
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    • 2017
  • 4차 산업혁명과 ICT 기술의 중요성이 증가함에 따라 소프트웨어 중심 사회가 초래되었다. 기존 소프트웨어 교육은 학습 환경구성에 제한적이었으며, 초기에 많은 비용이 발생하였다. 이를 해결하기 위하여 웹 컴파일러를 활용하는 형태의 학습 방법이 개발되었다. 웹 컴파일러는 다양한 소프트웨어 언어를 지원하며, 컴파일 결과를 사용자에게 웹을 통해 보여준다. 하지만 4차 산업혁명의 핵심기술인 인공지능에 대한 웹 컴파일러는 아직 미비한 상황이다. 본 논문에서는 구글 인공지능 라이브러리인 텐서플로우 기반의 웹 컴파일러를 설계, 구현하였다. nodeJS 기반의 서버에 텐서플로우와 텐서플로우 서빙, 파이썬 주피터를 구현하고, meteorJS 기반의 웹 서버를 구축하여 인공지능 학습을 위한 시스템을 구현하였다. 소프트웨어 중심 사회에서 인공지능 학습을 위한 도구로써의 활용이 가능할 것으로 기대된다.

알러젠 제거 옻나무 추출물 투여로 삶의 질이 개선된 불응성 직장암 환자 1례 (Quality of Life Improved with Allergen-removed Rhus Verniciflua Stokes based Traditional Korean Medicine on a Patient with Refractory Rectal cancer : Single Case Report)

  • 김나희;박재우;김경석;정현식;최원철;윤성우
    • 대한암한의학회지
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    • 제13권1호
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    • pp.55-61
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    • 2008
  • Nearly 800,000 new colorectal cancer cases are believed to be occur each year, which account for approximately 10% of all incident cancers, and mortality from colorectal cancer is estimated at nearly 450,000 per year. We report one patient with rectal cancer of stage III. The patient had a rectal cancer(StageIII T3N2M0) and underwent low anterior resection in 2004 followed by chemotherapy and radiotherapy. Lymph node metastases were found in 2005 and the patient was treated by palliative chemotherapy, which could not supress the lymph node metastases increase. The patient visited Kyunghee University East-West Neo Medical Center(KHNMC) in 2006 and was treated using allergen-removed Rhus Verniciflua Stokes(aRVS). Radiotherapy was done simultaneously in 2006. There was no evidence of recurrence since then. The patient showed no side effects. This case report brings forth the importance of a thorough study in rectal cancer in the traditional Korean medical point of view, along with the long-term effect of aRVS.

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괴사성 림프절염에 대한 임상적 고찰 (A Clinical Consideration of Necrotizing Lymphadenitis)

  • 유명종;조우령;김학선;이재동;김명구
    • 대한기관식도과학회지
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    • 제6권2호
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    • pp.164-171
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    • 2000
  • Background and Objectives: Necrotizing lymphadenitis or Kikuchi's disease is characterized by cervical lymphadenopathy of unknown etiology with unique histologic findings in young female patients. The importance of this disease lies in the fact that it can be easily misdiagnosed as malignant lymphoma, hence, clinicians need to aware of this disease entity. The purpose of this study is to report the clinicopathologic findings, radiographic findings, and many laboratory tests in order to contribute to the diagnosis and treatment of necrotizing lymphadenitis. Materials and Methods: We evaluated 31 patients, who were diagnosed as necrotizing lymphadenitis by excisional biopsy or fine needle aspiration cytology or ultrasound guided 18G cutting needle biopsy, retrospectively. Result : The median age was 24.8 years (range 12 to 43 years) and the male to female ratio was 1 : 2.4(9:22), with 14 females (45.1%) under 30 years. The common chief complaints were neck mass, easy fatigue and fever. Lymph node enlargement was limited to the cervical area in most cases (28cases : 90.3%). The involved lymph nodes were usually multiple (20cases : 64.5%), unilateral (26cases 83.9%) and small sized. Leukopenia (19cases : 61.3%) and elevation of ESR (18cases : 58.1%) appeared most frequently in the abnormal laboratory data. These symptoms will be gone spontaneoulsy without any specific treatment in several weeks or months. Conclusion : We should consider open biopsy or fine needle aspiration cytology or ultrasound guided cutting needle biopsy with lymph node in patients who have cervical lymphadenopathy with easy fatigue and fever, especially young women to exclude other conditions such as malignant lymphoma and tuberculosis, etc.

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Physiological Effects of GLT1 Modulation in Saccharomyces cerevisiae Strains Growing on Different Nitrogen Sources

  • Brambilla, Marco;Manuela Adamo, Giusy;Frascotti, Gianni;Porro, Danilo;Branduardi, Paola
    • Journal of Microbiology and Biotechnology
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    • 제26권2호
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    • pp.326-336
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    • 2016
  • Saccharomyces cerevisiae is one of the most employed cell factories for the production of bioproducts. Although monomeric hexose sugars constitute the preferential carbon source, this yeast can grow on a wide variety of nitrogen sources that are catabolized through central nitrogen metabolism (CNM). To evaluate the effects of internal perturbations on nitrogen utilization, we characterized strains deleted or overexpressed in GLT1, encoding for one of the key enzymes of the CNM node, the glutamate synthase. These strains, together with the parental strain as control, have been cultivated in minimal medium formulated with ammonium sulfate, glutamate, or glutamine as nitrogen source. Growth kinetics, together with the determination of protein content, viability, and reactive oxygen species (ROS) accumulation at the single cell level, revealed that GLT1 modulations do not significantly influence the cellular physiology, whereas the nitrogen source does. As important exceptions, GLT1 deletion negatively affected the scavenging activity of glutamate against ROS accumulation, when cells were treated with H2O2, whereas Glt1p overproduction led to lower viability in glutamine medium. Overall, this confirms the robustness of the CNM node against internal perturbations, but, at the same time, highlights its plasticity in respect to the environment. Considering that side-stream protein-rich waste materials are emerging as substrates to be used in an integrated biorefinery, these results underline the importance of preliminarily evaluating the best nitrogen source not only for media formulation, but also for the overall economics of the process.

Role of E-cadherin and cyclin D1 as predictive markers of aggression and clonal expansion in head and neck squamous cell carcinoma

  • Shergill, Khushdeep;Sen, Arijit;Pillai, Hari Janardanan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제44권4호
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    • pp.182-190
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    • 2018
  • Objectives: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide. Inconsistency in various histopathologic features for predicting nodal metastasis and overall prognosis and a better understanding of molecular mechanisms of tumourigenesis have shifted the focus to a search for more definitive predictive markers. To identify the role of two immunohistochemical (IHC) markers, E-cadherin and cyclin D1, as predictive markers of aggressiveness in HNSCC and to assess clonal expansion of tumour cells. Materials and Methods: A total of 66 cases of HNSCC with neck node dissection were studied. IHC was performed on primary tumour sections and lymph nodes showing metastatic deposits. Histopathological parameters such as tumour grade and TNM stage together with nodal status were compared according to expression of the two markers. Fischer's chi-square test was used to assess the correlation between the two markers and histopathological parameters. Results: Out of 66 cases studied, 37 showed LN metastasis. Most of the patients were male, and the most common tumour site was buccal mucosa. We found a significant association between loss of E-cadherin and node metastasis (P<0.001) and higher TNM stage (P<0.001). Cyclin D1 overexpression was significantly associated with only nodal metastasis (P=0.007). No significant association with tumour grade was found for either marker. The subgroup of E-cadherin loss with cyclin D1 overexpression was associated with the maximum incidence of nodal metastasis and higher TNM stage, highlighting the importance of using a combination of these two markers. A significant association was noted between the expression of markers at the primary site and at nodal deposits, indicating clonal expansion. Conclusion: A combination of the two markers E-cadherin and cyclin D1 can predict prognosis in HNSCC, although tumour heterogeneity may affect this association in some cases.

급성 신손상을 동반한 가와사키 쇼크증후군 1예 (Kawasaki Disease Shock Syndrome with Acute Kidney Injury and Hypertension)

  • 최재홍;김윤주;김영돈;한경희
    • Pediatric Infection and Vaccine
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    • 제24권2호
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    • pp.112-116
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    • 2017
  • 가와사키병은 다른 원인이 없는 발열과 함께 피부점막에 특징적인 병변을 보이는, 소아에서는 비교적 흔한 질환으로 일반적으로 급성기에는 혈역학적으로 안정적이다. 저자들은 심한 저혈압과 함께 급성 신손상이 있는 상태에서 내원한 8세 남아가 치료 중에 가와사키병으로 진단된 증례를 경험하였다. 최근에는 가와사키병 초기에 불안정한 혈역학적 상태를 가와사키병 쇼크증후군이라는 개념으로 정의하고 있다. 환아는 면역글로불린 치료 후 임상적으로 회복되었으나 관상동맥 확장 합병증이 확인되어 아스피린을 복용하고 있으며, 가와사키병의 합병증으로서는 비교적 드문 고혈압이 확인되어 베타 차단제를 사용하고 있다. 본 증례를 통해 가와사키병 쇼크증후군의 임상 양상을 알고, 혈관염이라는 가와사키병의 특성을 고려해볼 때 혈압 모니터링의 중요성을 깨닫게 되었다.