• Title/Summary/Keyword: Engine Selection

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Change of Mechanical Properties of Injection-Molded Glass-Fiber-Reinforced Plastic (GFRP) According to Temperature and Water Absorption for Vehicle Weight Reduction (차량 경량화를 위한 사출성형 유리섬유강화플라스틱의 온도 및 수분 흡수에 따른 기계적 물성 변화)

  • Chun, Doo-Man;Ahn, Sung-Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.2
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    • pp.199-204
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    • 2013
  • Owing to the global energy crisis, studies have strongly focused on realizing energy savings through vehicle weight reduction using light metal alloys or polymer composites. Polymer composites afford many advantages including enabling the fabrication of complex shapes by injection molding, and glass and carbon fibers offer improved mechanical properties. However, the high temperature in an engine room and the high humidity during the rainy season can degrade the mechanical properties of the polymer. In this study, the mechanical properties of injection-molded glass-fiber-reinforced polymer were assessed at a temperature of $85^{\circ}C$ and the maximum moisture absorption conditions. The result showed a 23% reduction in the maximum tensile strength under high temperature, 30% reduction under maximum moisture absorption, and 70% reduction under both heat and moisture conditions. For material selection during the design process, the effects of high temperature and high humidity should be considered.

Application Method of Task Ontology Technology for Recommendation of Automobile Parts (자동차부품 추천을 위한 태스크 온톨로지 기술의 적용방법)

  • Kim, Gui-Jung;Han, Jung-Soo
    • Journal of Digital Convergence
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    • v.10 no.6
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    • pp.275-281
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    • 2012
  • This research proposes the method to develop the recommendation system of automobile parts using task ontology technology. The proposed intelligent recommendation system is designed to learn the assembly process of automobile parts and the automobile parts are composed by ontology method for the recommendation of the parts. Using hierarchical taxonomy based on is-a relationship, the relationship between each part that makes up automotive engine was set. Each part has each different weighted value according to the knowledge of automobile experts. The weighted value is created by the number of selection that the users of the automobile recommendation system select while using the system and the final value calculated by the multiplication of the weighted value, which is recorded within the system. As a result, the users can easily identify which factor in which part is important by the output in the order of the priority. The intelligent recommendation system for automobile parts is a system to inform of the assembly, the usage and the importance of automobile parts without any specialized knowledge by expressing the parts that are closely related with the applicable parts when selecting any part on the basis of the generated data for the automobile parts that are difficult to access by users.

Study on Priority Selection of Export Strategic Core Technologies for IT Fusion Next Generation Agricultural Machines (IT융합 차세대 농기계 수출전략형 핵심기술 우선순위 선정에 관한 연구)

  • Chang, Dong-Il;Cho, Byoung-Kwan;Lee, Hoon-Soo;Chung, Sun-Ok;Park, Seung-Jae;Kim, Chul-Soo;Lee, Young-Hee
    • Journal of Biosystems Engineering
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    • v.36 no.6
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    • pp.491-499
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    • 2011
  • The objective of this study was to develop the export strategic core technologies for IT fusion next generation agricultural machines by the analysis of comprehensive and cooperative systems of industries, universities, and institutes. In order to achieve the objective of this study, an expert panel was formed and operated. The first survey was conducted by the Delphi method. For this the export strategic core technologies were surveyed and analyzed using the questionnaire. Based on the results of the first survey, the second survey was conducted. The questionnaire used for the second survey was designed by results of the first survey. The results of the second survey was analyzed by AHP method. The third survey was conducted based on the second one, and the final results were analyzed and the export strategic core technologies were developed through the expert meeting. The study results showed six export strategic core technologies as the followings : 1) environment-friendly engine technology for high performance 2) high performance/high efficiency power transmission system technology 3) development of measurement system technology for safety of agricultural products 4) field application of sensor networks 5) large size combine development technology for high performance 6) quality evaluation technology for agricultural products.

Chemical Genomics with Natural Products

  • Jung, Hye-Jin;Ho, Jeong-Kwon
    • Journal of Microbiology and Biotechnology
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    • v.16 no.5
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    • pp.651-660
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    • 2006
  • Natural products are a rich source of biologically active small molecules and a fertile area for lead discovery of new drugs [10, 52]. For instance, 5% of the 1,031 new chemical entities approved as drugs by the US Food and Drug Administration (FDA) were natural products between 1981 and 2002, and another 23% were natural product-derived molecules [53]. These molecules have evolved through millions of years of natural selection to interact with biomolecules in the cells or organisms and offer unrivaled chemical and structural diversity [14, 37]. Nonetheless, a large percentage of nature remains unexplored, in particular, in the marine and microbial environments. Therefore, natural products are still major valuable sources of innovative therapeutic agents for human diseases. However, even when a natural product is found to exhibit biological activity, the cellular target and mode of action of the compound are mostly mysterious. This is also true of many natural products that are currently under clinical trials or have already been approved as clinical drugs [11]. The lack of information on a definitive cellular target for a biologically active natural product prevents the rational design and development of more potent therapeutics. Therefore, there is a great need for new techniques to expedite the rapid identification and validation of cellular targets for biologically active natural products. Chemical genomics is a new integrated research engine toward functional studies of genome and drug discovery [40, 69]. The identification and validation of cellular receptors of biologically active small molecules is one of the key goals of the discipline. This eventually facilitates subsequent rational drug design, and provides valuable information on the receptors in cellular processes. Indeed, several biologically crucial proteins have already been identified as targets for natural products using chemical genomics approach (Table 1). Herein, the representative case studies of chemical genomics using natural products derived from microbes, marine sources, and plants will be introduced.

Two-Way Car Ferry Thrust Shaft Primary Support Part Structural Integrity Evaluation (양방향 카페리 추진축 1차 지지부 구조건전성 평가)

  • Kang, Byoung-Mo;Oh, Young-Cheol;Bae, Dong-Gyun;Ko, Jae-Yong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2013.10a
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    • pp.163-164
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    • 2013
  • Two-Way CAR-FERRY land and islands, islands to islands, the connection between sustainable marine transportation in conjunction with the increasing demand of tourists, according to the associated coastal maritime tourism and passenger transport has a role. Subsequent Two-Way CAR-FERRY and the increased ease of use due to berthing maritime accidents can be reduced. Two-Way CAR-FERRY as the draft (even) in the state on both sides of the propeller, because the propeller due to the small diameter, low speed forward flight by the reaction at the shaft and propeller damage can occur. Engine output accordingly, linear and torsional vibration reducer by, elastic coupling selection transverse vibration and shaft alignment (Shaft alignment) considering the shaft design (bearing size, width, thickness) and the primary drive shaft support portion of the hull structure of evaluated for quality.

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Inverse Document Frequency-Based Word Embedding of Unseen Words for Question Answering Systems (질의응답 시스템에서 처음 보는 단어의 역문헌빈도 기반 단어 임베딩 기법)

  • Lee, Wooin;Song, Gwangho;Shim, Kyuseok
    • Journal of KIISE
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    • v.43 no.8
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    • pp.902-909
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    • 2016
  • Question answering system (QA system) is a system that finds an actual answer to the question posed by a user, whereas a typical search engine would only find the links to the relevant documents. Recent works related to the open domain QA systems are receiving much attention in the fields of natural language processing, artificial intelligence, and data mining. However, the prior works on QA systems simply replace all words that are not in the training data with a single token, even though such unseen words are likely to play crucial roles in differentiating the candidate answers from the actual answers. In this paper, we propose a method to compute vectors of such unseen words by taking into account the context in which the words have occurred. Next, we also propose a model which utilizes inverse document frequencies (IDF) to efficiently process unseen words by expanding the system's vocabulary. Finally, we validate that the proposed method and model improve the performance of a QA system through experiments.

The Development of a Trial Curriculum Classification and Coding System Using Group Technology

  • Lee, Sung-Youl;Yu, Hwa-Young;Ahn, Jung-A;Park, Ga-Eun;Choi, Woo-Seok
    • Journal of Engineering Education Research
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    • v.17 no.4
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    • pp.43-47
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    • 2014
  • The rapid development of science & technology and the globalization of society have accelerated the fractionation and specialization of academic disciplines. Accordingly, Korean colleges and universities are continually dropping antiquated courses to make room for new courses that better meet societal demands. With emphasis placed on providing students with a broader range of choices in terms of course selection, compulsory courses have given way to elective courses. On average, 4 year institutions of higher learning in Korea currently offer somewhere in the neighborhood of 1,000 different courses yearly. The classification of an ever growing list of courses offered and the practical use of such data would not be possible without the aid of computers. For example, if we were able to show the pre/post requisite relationship among various courses as well as the commonalities in substance among courses, such data generated regarding the interrelationship of different courses would undoubtedly greatly benefit the students, as well as the professors, during course registration. Furthermore, the GT system's relatively simple approach to course classification and coding will obviate the need for the development of a more complicated keyword based search engine, and hopefully contribute to the standardization of the course coding scheme in the future..Therefore, as a sample case project, this study will use GT to classify and code all courses offered at the College of Engineering of K University, thereby developing a system that will facilitate the scanning of relevant courses.

The Effect of technical competence according to commercialize the company's technology incubator support and management performance stage (창업보육기업의 기술사업화에 따른 기술역량이 지원과 경영성과단계에 미치는 영향)

  • Jeon, In-Oh
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.325-340
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    • 2012
  • The present study, the technology commercialization through support of government enterprise incubator, incubator companies examined, and the support of the government in accordance with the technical competence necessary steps management performance steps, support conditions required were investigated. Government support of technology commercialization support business performance necessary steps to support the needs of the incubator companies and step conditions. Therefore, need funding and funding support, and the time and duration of the condition of the steps in the support business performance, the conduct of the government's support is the most needed step, showed a new growth engine projects of the application and selection screening, sector was.

The Hydrodynamical Study on the Selection of Planing Hull Forms. (Planing Hull의 선형선택(船型選擇)에 따르는 유체역학적(流體力學的) 고찰(考察))

  • Sun-Young,Pak;Sang-Hyouk,Choi
    • Bulletin of the Society of Naval Architects of Korea
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    • v.2 no.1
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    • pp.9-14
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    • 1965
  • Ship designers make every efforts to get faster ships in accordance with the development of the Naval Architecture. But for the speed lying over factor length ratio 2.5-3.0, we could put a powerful engine into the conventional round bottom displacement type vessels, but it is very difficult in view point of economy, weight and volume. The principal cause of these speed obstacles is the wave making resistance and researchers are trying to decrease this resistance. One of the resolving ways, planing hulls were applied to small high boats. Planing hull's advantage is not restricted to speed, but the workmanship of the planing hull is easier than those of displacement type vessels of round bottom. Planing hull, therefore, are widely applicable to the intermediate speed boats, which don't have enough high speed to take planing advantage, as well as high speed boats. We will discuss related phenomena of the planing hull in details and this paper we particularly interested in the interjection point(speed length ratio 3.0-3.5 by Mr. D. De Groots) between semi-planing and full planing hulls on the resistance characteristic curve. The paper by Prof. Keuck Chun Kim, "Some Characteristics of Straight Framed V-bottom Hull Forms", Journal of the society of Naval Architects of Korea, Vol.1, No.1, Dec.5, 1964, is referred to the V-bottom hull forms belonging to low speed region and determines practical applicable limit of the speed length ratio combined with construction costs, under which are still used by large commercial vessels. This is the interesting contrast between his and authors. We will further discuss the speed length ratio which is considered as a beginning point to planing effect. For this analysis, we choose 3 model ships: Model (1) and (2) have the same principal dimensions, model 3 varied dimension. Model (1) is full-planing hull, (2) is semi-planing hull and (3) is complete planing hull. They are aimed to collect proper design data for purposed ships.

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Examining Categorical Transition and Query Reformulation Patterns in Image Search Process (이미지 검색 과정에 나타난 질의 전환 및 재구성 패턴에 관한 연구)

  • Chung, Eun-Kyung;Yoon, Jung-Won
    • Journal of the Korean Society for information Management
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    • v.27 no.2
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    • pp.37-60
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    • 2010
  • The purpose of this study is to investigate image search query reformulation patterns in relation to image attribute categories. A total of 592 sessions and 2,445 queries from the Excite Web search engine log data were analyzed by utilizing Batley's visual information types and two facets and seven sub-facets of query reformulation patterns. The results of this study are organized with two folds: query reformulation and categorical transition. As the most dominant categories of queries are specific and general/nameable, this tendency stays over various search stages. From the perspective of reformulation patterns, while the Parallel movement is the most dominant, there are slight differences depending on initial or preceding query categories. In examining categorical transitions, it was found that 60-80% of search queries were reformulated within the same categories of image attributes. These findings may be applied to practice and implementation of image retrieval systems in terms of assisting users' query term selection and effective thesauri development.