• 한국해양공학회지
• /
• 제21권1호
• /
• pp.64-68
• /
• 2007

Recently, there has been considerable research in the field of application of Laser-Arc hybrid welding for superstructures, such as ship-structures, transport vehicles etc. However, the study on heat distribution and welding residual stress of hybrid weld by numerical simulation leaves much to be desired. Therefore, in this study, an optimized welding condition and numerical simulation for hybrid welding, using previous numerical analysis to calculate the heat source for hybrid welding, has been analyzed. For this purpose, fundamental welding phenomena of the hybrid process, using Laser and, is investigated. In order to calculate temperature and residual stress distribution in hybrid welds, a finite element heat source model is developed on the basis of experimental results and characteristics of temperature. Residual stress distribution in hybrid welds are understood from the result of simulation, and compared with the experimental values.

• Carbon letters
• /
• 제14권2호
• /
• pp.105-109
• /
• 2013

Effects of the amount of nickel powder (Ni) in Ni-carbon fiber (CF) hybrid filler systems on the conductivity(or resistivity) and thermal coefficient of resistance (TCR) of filled high density polyethylene were studied. Increases of the resistivity and TCR with increasing Ni concentration at a given hybrid filler content were observed. Using the fiber contact model, we showed that the main role of Ni in the hybrid filler system is to decrease the interfiber contact resistance when Ni concentration is less than the threshold point. The formation of structural defects leading to reduced reinforcing effect resulted in both a reduction of strength and an increase of the coefficient of thermal expansion in the composite film; these changes are responsible for the increases of both resistivity and TCR with increasing Ni concentration in the hybrid filler system.

• 복합신소재구조학회 논문집
• /
• 제4권2호
• /
• pp.25-30
• /
• 2013

In this study a hybrid safety barrier system consisting of steel rail and carbon fiber reinforced polymer (CFRP) post is considered. W hile CFRP post is selected for impact energy reflection due to its high strength, steel rail is selected for impact energy absorption due to its high ductility. A numerical model considering the elastoplastic behavior of steel is formulated to simulate the dynamic responses of the hybrid system subject to an impact load. A hybrid roadside guard rail system of steel rail and CFRP post is proposed and analyzed with a case study. The numerical model for the hybrid roadside guard rail system is used to find optimized design of the proposed hybrid system.

• 한국소음진동공학회논문집
• /
• 제13권7호
• /
• pp.524-531
• /
• 2003

This paper presents an active vibration control of a flexible beam structure using a hybrid mount which consists of elastic rubber and Piezoelectric material. After identifying stiffness and damping properties of the rubber and piezoelectric elements, a mechanical model of the hybrid mount is established. The mount model is then Incorporated into the beam structure, and the governing equation of motion is obtained in a state space. A sliding mode controller is designed in order to actively attenuate the vibration of the beam structure subjected to high frequency and small magnitude excitations. The controller is experimentally realized and control responses such as acceleration of the beam structure and force transmission through the hybrid mount are evaluated. In addition. a comparative work is done between the passive and hybrid mount systems.

• 반도체디스플레이기술학회지
• /
• 제20권4호
• /
• pp.10-15
• /
• 2021

Cache bypassing schemes have been studied to remove unnecessary updating the data in cache blocks. Among them, a statistics-based cache bypassing method for asymmetric-access caches is one of the most efficient approach for non-voliatile memories and shows the lowest cache access latency. However, it is proposed under the condition of the normal cache system, so further study is required for the hybrid cache architecture. This paper proposes a novel cache bypassing scheme, called hybrid bypassing block selector. In the proposal, the new model is established considering the SRAM region and the non-volatile memory region separately. Based on the model, hybrid bypassing decision block is implemented. Experiments show that the hybrid bypassing decision block saves overall energy consumption by 21.5%.

• 한국실내디자인학회논문집
• /
• 제24권3호
• /
• pp.146-155
• /
• 2015

It is an undeniable fact that the modern people's interest in knowledge and information and their roles are some of the core factors used to define the modern society. Besides, as phenomena indicating and leading the modern society, we have fusion, hybrid and convergence, etc. that combine several different elements into a new one. Such changes in social, cultural and technological circumstances require a paradigm shift for the composition of knowledge and information facilities and space. However, more diversified and advanced recently, interfaces for the delivery of knowledge and information cause users to show new behaviors and even change the spatial concept with space composition elements hybridized. Especially for the space of libraries, it is necessary to access and utilize any forms of knowledge and information data (digital + analog) regardless of time and space limitations and approach with an integrated spatial concept likely to change flexibly depending on social demands. In this light, this study aims to make a basic proposal for sustainable integrated-type hybrid space for the space of a public library in this era of knowledge and information. Particularly, this study intends to seek a way to establish a hybrid space model that can effectively converge the most important factors of the space of libraries (human-space(network)-information). With 18 different cases, this study analyzed knowledge and information composition systems, knowledge and information delivery systems and users' space systems. As a result, this study extracted 3 kinds of models, an information-based model, a culture-based model and an education-based model, with the integrated hybrid space model of knowledge and information facilities

• 한국콘텐츠학회논문지
• /
• 제16권2호
• /
• pp.513-524
• /
• 2016

본 연구는 하이브리드 수업 구성에 따른 효과를 분석하기 위하여 인성교양과목 중의 하나인 '21세기 리더십' 과목을 선정하고, 이를 동일한 과목으로 2개 반을 개설하여 격주형 모형과 혼합형 모형으로 수행하고 이를 비교 분석하였다. 이를 위해 해당 과목을 수강했던 64명을 대상으로 자료를 수집하였고, SPSS 21.0프로그램을 통해 자료를 분석하였다. 연구결과, 첫째, 리더십 지식은 격주형과 혼합형 모두 유의하게 향상되었으며, 총괄평가인 기말고사 성적은 혼합형에서 유의하게 높은 것으로 나타났다. 둘째, 무조건적인 자기수용의 경우, 혼합형에서만 유의한 증가가 있었다. 셋째, 리더십 생활기술의 증진은 혼합형에서만 유의한 증가가 있었다. 이러한 연구결과를 바탕으로 리더십 과목의 경우, 학생들의 만족도를 높이고 동시에 학습효과도 함께 극대화할 수 있도록 혼합형 하이브리드 모형을 채택하되, 학생들이 참여와 실습을 통해 인간관계를 경험하고 리더십을 개발할 수 있도록 온라인 강의보다는 오프라인 강의에 비중을 더 두는 것이 효과적일 것임을 결론짓고 본 연구에 대한 제한점과 후속연구에 대한 제언을 논의하였다.

• 한국공간구조학회논문집
• /
• 제11권2호
• /
• pp.101-110
• /
• 2011

현재 건축 및 토목 구조물의 진동제어에 있어서 준능동제어에 대한 연구가 많이 수행되고 있으며 준능동제어 시스템은 수동제어와 능동제어의 장점을 가지고 있다. 최근 적은 전기 에너지로 제어가 가능한 MR 감쇠기가 개발되어 준능동제어 분야에 적용되고 있으며 이러한 MR 감쇠기를 스마트 감쇠기라 불리고 있다. 본 논문에서는 실시간으로 제어가 가능한 MR 감쇠기를 인접한 두 건축물 사이에 설치하여 제어성능을 알아보고자 한다. 또한, groundhook과 skyhook 제어 알고리즘을 결합한 복합제어 모델을 인접한 건축물의 진동제어에 적용하여 복합제어 모델의 제어성능을 알아보고자 한다. 복합제어 모델을 적용하여 인접한 두 건축물의 진동제어 성능을 분석한 결과, 복합제어 모델이 인접한 두 건축물의 진동제어에 매우 효과적인 것을 알 수 있었다.

• 한국자동차공학회논문집
• /
• 제18권4호
• /
• pp.18-30
• /
• 2010

As the automobile industry is developing, the number of deaths and injuries has increased. To reduce the damages from automobile accidents, the government of each country proposes experimental conditions for reproducing the accident and establishes the vehicle safety regulations. Automotive manufacturers are trying to make safer vehicles by satisfying the requirements. The Hybrid III crash test dummy is a standard Anthropomorphic Test Device (ATD) used for measuring the occupant's injuries in a frontal impact test. Since a real crash test using a vehicle is fairly expensive, a computer simulation using the Finite Element Method (F.E.M.) is widely used. Therefore, a detailed and robust F.E. dummy model is needed to acquire more accurate occupant injury data and behavior during the crash test. To achieve this goal, a detailed F.E. model of the Hybrid III 5th percentile female dummy is constructed by using the reverse engineering technique in this research. A modeling process is proposed to construct the F.E. model. The proposed modeling process starts from disassembling the physical dummy. Computer Aided Design (CAD) geometry data is constructed by three-dimensional (3-D) scanning of the disassembled physical dummy model. Based on the geometry data, finite elements of each part are generated. After mesh generation, each part is assembled with other parts using the joints and rigid connection elements. The developed F.E. model of dummy is simulated based on the FMVSS 572 validation regulations. The results of simulation are compared with the results of physical tests.

• Journal of Information Technology Applications and Management
• /
• 제23권1호
• /
• pp.45-59
• /
• 2016

An ensemble classifier is a method that combines output of multiple classifiers. It has been widely accepted that ensemble classifiers can improve the prediction accuracy. Recently, ensemble techniques have been successfully applied to the bankruptcy prediction. Bagging and random subspace are the most popular ensemble techniques. Bagging and random subspace have proved to be very effective in improving the generalization ability respectively. However, there are few studies which have focused on the integration of bagging and random subspace. In this study, we proposed a new hybrid ensemble model to integrate bagging and random subspace method using genetic algorithm for improving the performance of the model. The proposed model is applied to the bankruptcy prediction for Korean companies and compared with other models in this study. The experimental results showed that the proposed model performs better than the other models such as the single classifier, the original ensemble model and the simple hybrid model.