• Title/Summary/Keyword: SAFE

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VANET 환경에서 신뢰적인 에이전트 선출을 이용한 Safe-Tunneling Zone (Safe-Tunneling Zone using election the reliable agent in VANET)

  • 오하나;김아란;신용태
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2010년도 한국컴퓨터종합학술대회논문집 Vol.37 No.1(D)
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    • pp.371-374
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    • 2010
  • 본 논문은 Vehicular Ad-hoc Network(VANET)환경에서 V2V간의 신뢰적 통신을 지원하기 위해 Safe-Tunneling Zone을 제안한다. 기존의 무선 환경에서는 신뢰적인 경로산출을 위해 ARAN에서 제안된 hop-by-hop 인증을 사용하여 신뢰성은 충족되나 많은 시간과 자원을 소비하는 단점이 있다. 그러나 본 논문에서 제안한 Safe-Tunneling Zone은 송 수신 하고자하는 차량이 각각 신뢰적 에이전트를 선택하고, 선택된 에이전트는 서로의 ID, Rn을 바탕으로 생성된 세션키를 교환함으로서 상호간의 인증을 수행한다. 이와 같이 본 논문에서는 Safe-Tunneling Zone을 통해 기존의 신뢰적 경로 산출 기법보다 수행과정 절차의 간소화, 자원소비 감소, 종단 간의 신뢰적 경로를 통한 데이터의 기밀성 또한 제공 가능하도록 한다.

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가계의 위험자산과 안전자산 투자분석 -금융자산을 중심으로- (The Household's investment on risky and safe financial assets)

  • 양정순
    • 가정과삶의질연구
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    • 제14권3호
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    • pp.109-120
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    • 1996
  • While theories of portfolio selection have been developed very little is known about how individuals actually go about constructing their asset potfolios. This study investigates empirically the characteristics of household's assets and which factor associated with risky and safe asset amount. Data used in this study consisted of 2,164 households and the statistics employed to analyze the data are univariate procedure Logit analysis and OLS. The results of this study were as follows: Among 2,164 households 505 housholds(23.3%) had risky assets. Average risky asset amount is 8,351,500 won and average safe asset amount is 7,086,900 won. Region education and occupation of household head home ownership transfer and other income and total expenditure had significant effects on either and other income and total expenditure had significant effects on either household having risky asset or safe asset. Financial income transfer and other income and total expenditure had significantly p sitive relation with the risky asset amount. Whereas age and the occupation of household head the sense of economic wellbeing earned financial tranfer and other income and total expenditure had significantly positive relation with safe asset amount.

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A Study on the Method of Safe Shiphandling in Violently Rough Sea by Typoon or Hurricane

  • Lee, Chun-Ki
    • 한국항해항만학회지
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    • 제34권2호
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    • pp.123-129
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    • 2010
  • The object of this study is to develop the method of safe conducting of a vessel through stormy sea when we encounter typoon or hurricane on ocean. The scope of investigation in this paper will be limited to safe maneuvering related only with rolling motions of a vessel. The processes of investigations are as follows; Firstly, we decide a CPA(Closest Point of Approach) with the center of the storm and decide significant wave height($H_{1/3}$) by SMB method and then calculate wave height of the highest of 1000 waves($H_{1/1000}$) and other data. Secondly, we make mathematical model of rolling motions of the vessel on the stormy sea and calculate the biggest rolling angle of the vessel and etc. Thirdly, we decide the most safe maneuvering method to ride out the stormy sea. By the above mentioned method we are able to calculate the status of the stormy sea and ships motions to be encountered and ride out safely through violently rough sea.

안전항 판례동향과 시사점에 관한 연구 (A study on the precedent trend of safe port and its Implication)

  • 김태우;이원정
    • 대한안전경영과학회지
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    • 제12권3호
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    • pp.93-99
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    • 2010
  • As more than 90% of global trade is carried by sea there is little doubt that the safety of the ports at which the world's trading fleet call is of critical concern. The concept of 'safe port' continues to be an area of critical concern for charterers and ship-owners. In light of increased global security and health risks the recognised principles are under security. This paper examines the nature of safe port, and analyses the precedent trend of safe port and its Implication

NC 밀링에서 짧은 공구설치 방법으로 생산성 향상 (NC Milling Productivity Incensement by Short Milling Tool Setting Method)

  • 김수진
    • 한국정밀공학회지
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    • 제25권5호
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    • pp.60-68
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    • 2008
  • The tool overhang length affects tool deflection and chatter that should be reduced for machined surface quality, productivity and long tool lift. The shortest tool setting algorithm that uses a safe space is proposed and applied with simulation software in NC machining. The safe space in the coordinate fixed in the tool is computed by the virtual machining system that simulates NC machining by stock model, tool model and NC code. The optimal tool assembly that has largest diameter and shortest length is possible using the safe space. This algorithm has been applied over fifty companies for safe and rigid tool setting. The collision accident between holder and stock was reduced from 3 to 0 a year and the productivity was incensed about 15% by using faster feed rate acceptable for shorten tool length.

Re-SSS: Rebalancing Imbalanced Data Using Safe Sample Screening

  • Shi, Hongbo;Chen, Xin;Guo, Min
    • Journal of Information Processing Systems
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    • 제17권1호
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    • pp.89-106
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    • 2021
  • Different samples can have different effects on learning support vector machine (SVM) classifiers. To rebalance an imbalanced dataset, it is reasonable to reduce non-informative samples and add informative samples for learning classifiers. Safe sample screening can identify a part of non-informative samples and retain informative samples. This study developed a resampling algorithm for Rebalancing imbalanced data using Safe Sample Screening (Re-SSS), which is composed of selecting Informative Samples (Re-SSS-IS) and rebalancing via a Weighted SMOTE (Re-SSS-WSMOTE). The Re-SSS-IS selects informative samples from the majority class, and determines a suitable regularization parameter for SVM, while the Re-SSS-WSMOTE generates informative minority samples. Both Re-SSS-IS and Re-SSS-WSMOTE are based on safe sampling screening. The experimental results show that Re-SSS can effectively improve the classification performance of imbalanced classification problems.

속력을 고려한 선박충돌회피모델에 관한 연구 (A Study on the Ship Collision Avoidance Model considered Speed)

  • 양형선
    • 한국항해항만학회지
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    • 제30권10호
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    • pp.779-785
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    • 2006
  • 선박의 충돌회피 방법을 제시하는 관점에 있어, 두 선박의 조우각도에 따라 속력이 충분히 고려되어야 할 것이다. 하지만 선박의 충돌회피를 위해 새롭게 연구된 근접상황 선박충돌회피지원 모델의 안전경계영역(Safe-Guard Ring) 설정은 본선과 상대선박의 속력비가 약 1.7이하로 제한되어 있으므로 제한된 범위 이외의 경우에서 충돌 위험이 존재 할 수 있다. 따라서 본 연구에서는 두 선박이 조우하는 각도 및 속력을 고려한 안전경계영역 설정을 연구함으로써 안전한 충돌회피 조종을 위한 선박충돌회피모델을 제시하고자 한다.

의도적 재식술을 위한 비외상성 안전 발치법 (Atraumatic Safe Extraction for Intentional Replantation)

  • 최용훈;배지현;김영균
    • 대한치과의사협회지
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    • 제48권7호
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    • pp.531-537
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    • 2010
  • Intentional replantation is useful for failed cases of conventional dental treatment - including root canal treatment - to restore the tooth in question. Based on a recent study, it is relatively very successful; prognosis is good for a long period. On the other hand, a tooth that becomes an indication of intentional replantation is often severely weakened throughout several treatments. Moreover, with multi-rooted teeth, extracting without root fracture is difficult. Safe extraction that is free of coronal or root fracture is important, but little information is known as to a concrete, safe way of extraction. There are a few considerations for safe extraction. First, a tooth with orthodontic extrusion force is easier for extraction due to its increased mobility; it increases the amount of the periodontal ligament, which is essential for re-attachment. As a safe way of extraction, the use of physics forceps has been introduced recently; it minimizes damage to the gingiva and alveolar hone. This paper reports the good result of using atraumatic safe extraction via both orthodontic extrusion and physics forceps$^{(R)}$.

안전한 주행을 위한 정보 격자지도 기반의 경로계획 (Path Planning Using an Information Grid Map for Safe Navigation)

  • 정민국;박중태;송재복
    • 대한기계학회논문집A
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    • 제36권6호
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    • pp.623-628
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    • 2012
  • 기존의 경로계획 방법은 최단거리의 경로를 생성하는 것에 목적을 둔다. 그러나 이렇게 선택된 최적의 경로가 안전한 주행을 보장해주지는 못하는데, 이는 종종 좁은 통로나 이동 장애물이 많은 영역으로 경로를 생성하기 때문이다. 그러므로 로봇은 정보 격자지도를 이용하여 안전하게 이동할 수 있는 경로를 생성하는 것이 필요하다. 이 정보 격자지도는 기존의 지도가 가지고 있는 영역의 정보 외에 유도지역과 위험지역을 포함한다. 안전한 경로는 인력과 척력을 이용하여 위험지역을 우회하고 유도지역으로 접근되어 생성된다. 실험 및 시뮬레이션은 제안된 방법이 안전한 영역으로 경로를 생성시켜, 안전하게 주행하는 데 유용하다는 것을 보여준다.