• Proceedings of the Korean Information Science Society Conference
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• 2010.06d
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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.

• Journal of Families and Better Life
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• v.14 no.3
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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.

• Journal of Navigation and Port Research
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• v.34 no.2
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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.

• Journal of the Korea Safety Management & Science
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• v.12 no.3
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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

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.197-197
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• 2017

• Journal of the Korean Society for Precision Engineering
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• v.25 no.5
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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.

• Journal of Information Processing Systems
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• v.17 no.1
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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.

• Journal of Navigation and Port Research
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• v.30 no.10 s.116
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• pp.779-785
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• 2006

From a point of view of suggesting the method to avoid ship's collision, the speed of ships has to be considered sufficiently according to encounter angle of ships. But the new safe-guard ring of ship's collision avoidance support model in the close quarters is established assuming that the ratio of own ship' speed to a target ship's speed is less than about 1.7. Therefore in this paper, as doing a study concerned with the establishment of safe-guard ring reflected the encounter angle and the speed of ships, we will propose the new model of ship collision avoidance for safe maneuver of ship's collision avoidance.

• The Journal of the Korean dental association
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• v.48 no.7
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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$^{(R)}$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.6
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• pp.623-628
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• 2012

Conventional path planning methods have focused on the generation of an optimal shortest path to the goal. However, this optimal path cannot guarantee safe navigation, because it can often lead to a narrow area. Therefore, we propose a Coulomb's law-based safe path planning method that uses an information grid map. The information grid map includes four types of information: occupied, empty, guide, and dangerous areas. A safe path can be generated away from the dangerous area and close to the guide area by repulsive and attractive forces, respectively. Experiments and simulations show that the proposed method can generate paths inside the safe region and is useful for safe navigation.