검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 334

        82.
        2018.04 구독 인증기관 무료, 개인회원 유료
        Since the 2010 year, an occurring number of grand scale earthquakes which above magnitude 5.0 have increased in the world. Many types of research that deal with reducing the damage to the structure from a large-scale earthquake have proceeded. A system which could mitigate strong vertical earthquake's acceleration might apply to structure, since big earthquake cases that occurred lots of loss in Tokyo and Kobe of Japan. A plenty of bearings have installed to mitigate vibration but many parts of these lack efficient ability what we want. In addition, former vertical isolation bearings to apply for the structure have both price and size limits according to material characteristics. Therefore, this paper proposes a new type of device that is made by utilized engineering plastic and improves hitherto used vertical isolation bearing's fault.
        3,000원
        83.
        2018.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 고준위폐기물 처분기술 개발과 관련하여 현장실증 연구를 위해 사용될 공학규모 이상의 균질 완충재 블록 을 제작하기 위한 새로운 방법론을 제시하는 것이다. 이와 관련하여 플롯팅 다이(floating die) 방식의 프레스 재하 및 냉간 등방압프레스(CIP; Cold Isostatic Press) 기법을 국내 최초로 완충재 제작에 적용하였다. 또한 소요 밀도기준을 충족하는 완충재 블록을 생산하기 위한 최적의 제작조건(프레스 및 CIP의 소요 압력)과 현장 적용성을 분석하였다. 상기 기법의 적용을 통해 완충재 블록 내 밀도분포 편차가 현저히 감소하였으며, 이와 동시에 평균 건조밀도가 소폭 상승하고 약 5%의 크기가 감소하였다. 또한 CIP 적용을 통해 응력이완(stress release) 현상이 감소하고, 이로 인해 시간 경과에 따른 표면균열 발생이 현저히 저감됨을 시험제작을 통해 확인하였다. 본 연구에서 제시된 방법론은 공학규모 이상의 균질한 완충재 블럭을 성형할 수 있으며, 또한 이는 선진핵주기 고준위폐기물처분시스템(AKRS; Advanced Korea Reference Disposal System of HLW)의 완충재 소요 밀도기준을 충족하는 것으로 분석되었다.
        4,600원
        84.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In the international businesses human resource elements acquired in different countries might have different values in varied industries due to the different quality of education and experiences in the original countries. Using selection models to evaluate expected values in earnings equation of human resource elements such as education and experiences etc. acquired in sending countries, system equations are expanded to examine also the values of science and engineering degrees in technology jobs with selectivity bias correction. This paper used the US census survey data of 2015 on earnings, academic degrees, occupations etc. The US has long maintained the policy of accepting more STEM workers than any other countries and helped maintaining own technological leadership. Assuming per capita GDP gap between the sending country and the US downgrades immigrant human resource quality, it rarely affects occupational selection but depresses earnings on average by two or more years’ worth of education. Immigrant quality index in the sense of GDP gap appears to be a valid tool to assess the expected earnings of the worker with. Engineering degrees increase significantly the probability of selecting not only engineering jobs but also general management jobs, as well as increasing the expected earning additionally over nine years’worth of education. Getting a technology job is additionally worth about four years of education. Economics and business degrees are worth additionally almost six years of education but humanities degrees depress expected earnings. Since years after immigration does not very fast enhance earnings capacity, education level and English language ability might be more useful criteria to expect better future earnings by.
        4,000원
        85.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to provide basic data to help ensure the safety and enhance industrial competitiveness of plant construction projects by analyzing the safety management status of, mainly, chemical engineering plant construction projects, and proposing specific measures and models to reduce human/educational, technical/systemic, institutional disasters. This study was done using literature research and case study/empirical study methods. The results of this study are summarized as follows. First, we classified the major disasters from the quarterly released ‘major diaster cases in construction business’from Korea Occupational Safety and Health Agency according to the type of construction and presented the causes and prevention measures.
        4,000원
        89.
        2017.11 구독 인증기관·개인회원 무료
        광에너지 상향 전환 기술(이하 Upconversion, UC)은, ‘낮은 에너지의 두 개 혹은 그 이상의 광자를 이용해 높은 에너지를 가지는 하나의 광자를 생산해내는 기술’로 비전통적인 광에너지 전환기술의 하나이다. UC 는 광자가 에너지원으로 이용되는 다양한 광학기반 기기(예 : 태양전지)의 광감응 효율을 향상시킬 수 있는 새로운 기술로 평가받고 있으며, 이외에도 Bioimaging 이나 광학센서 등에 높은 활용가치를 지니고 있다. 본 연구발표에서는 삼중항 소멸에 기반한 UC 기술의 기본원리를 소개하고 최신 기술개발 단계와 차기 환경-에너지 공학에의 응용가능분야를 살펴본다. 또한 실제로 본 연구진에서 개발한 다양한 UC 물질의 제조법을 소개하고, Sub-bandgap 에너지의 광자 조사시 UC 에 의해 광촉매가 광활성화된 연구결과와 이외의 다양한 응용분야에 대해 살펴본다.
        91.
        2017.10 구독 인증기관·개인회원 무료
        In international businesses human resource elements acquired in different countries might have different values in varied industries due to different quality of education and experiences in original countries. Using existing models to evaluate expected values of human resource elements such as education and experience setc. acquired in sending countries they are expanded to examine also the values of science and engineering degrees in technology jobs with selectivity bias correction. This paper used the US census survey data of 2015 on earnings, academic degrees etc. to contrast qualitative effects with quantitative effects of human resource elements compared to those in the native and/or white group.
        92.
        2017.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        ZnO micro/nanocrystals with different morphologies were synthesized by thermal evaporation of various zinc source materials in an air atmosphere. Zinc acetate, zinc carbonate and zinc iodide were used as the source materials. No catalysts or substrates were used in the synthesis of the ZnO crystals. The scanning electron microscope(SEM) image showed that the morphology of ZnO crystals was strongly dependent on the source materials, which suggests that source material is one of the key factors in controlling the morphology of the obtained ZnO crystals. Tetrapods, nanogranular shaped crystals, spherical particles and crayon-shaped crystals were obtained using different source materials. The X-ray diffraction(XRD) pattern revealed that the all the ZnO crystals had hexagonal wurtzite crystalline structures. An ultraviolet emission was observed in the cathodoluminescence spectrum of the ZnO crystals prepared via thermal evaporation of Zn powder. However, a strong green emission centered at around 500 nm was observed in the cathodoluminescence spectra of the ZnO crystals prepared using zinc salts as the source materials.
        3,000원
        93.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Urban planning and engineering undergraduate students need to understand the earth physical systems and that how human beings interact with the earth systems to planning and engineering urban area. The eco-friendly or geofriendly design and planning of an urban area is a critical issue not only for economic benefits but more importantly for the sustainable future of urban life. However, little study has been done dealing with the urban engineering students’ understanding of the earth as a system and what pedagogical approach is appropriate to improve their understanding of the earth as a system. This study is to investigate the impact of a purposely designed ESS course on urban engineering students’ understanding of the earth as a system and their perceptions about the instructional approaches of the course on their learning competency. This study utilized a mixed-methodology with three main data sources: concept maps, student’s perception survey about their learning competency, and course contents. Both the survey and concept maps were analyzed quantitatively as well as qualitatively. The result of this study showed that the urban engineering students’ experience of team-based research about the topic they chose based on their own interest had a positive impact on their understanding of the earth as a system and their learning competency. The results of this study suggest that structuring and presenting the earth system contents in the context of engineering students’ understanding and their future career be effective not only for the improvement of students’ content knowledge but also for the enhancement of their learning competency such as creativity and problem-solving skills in everyday life situation
        4,000원
        94.
        2017.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 논문에서는 쌍동형 카페리에 대한 기본구조설계 및 구조해석을 위한 기법을 제시한다. 카페리와 같이 길이가 50미터 이상이 고, 길이/폭의 비가 12보다 큰 중/소형 고속선박의 강도해석에 대한 규정이나 방법론은 아직까지 명확하게 제시되지 않고 있다. 따라서 본 논문에서는 한국선급 규정을 이용하여 부재 스캔틀링을 수행하였고, 설계안에 대한 구조강도 검증을 위해서 카페리 전용선박 기준을 추 가적으로 적용하여 검토하였다. 특히, 카페리 전용선박 기준을 이용하여, 선체거더 최종강도를 추가적으로 수행하였으며, 기존 기준에 의 한 설계의 모호성을 극복하도록 제안하였다. 본 연구를 통해 도출된 연구 결과는 앞으로 고속 쌍동형 카페리의 구조설계 및 구조해석에 관련된 기본적인 자료로 유용하게 활용될 것으로 예상되며, 현재 설계된 쌍동형 카페리의 부재 치수는 한국선급 기준에 충분히 만족하면 서 구조적으로 안전하다.
        4,000원
        96.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        BIM(building information modeling) has been actively applied to construction industries and to maximize its application through the life cycle of structure, various relevant technologies have been proposed. In particular, 4D sequencing management and 5D cost-related management were introduced as an improved version of the design review and interface control by 3D information design. On the other hand, the virtual construction using virtual construction equipment can sophisticatedly handle capacity, dynamic movement, collision boundaries of actual construction machines but it still stays at a low level in a technical sense. In this study, simulation systems based on BIM involving virtual construction equipment have been developed; then it is applied to the actual construction project to evaluate the safety and efficiency of construction equipments. It was confirmed that the simulation systems can be utilized to construct virtual construction site by using an effective 3D library of construction equipment and can plays a key role to secure construction safety and economic feasibility. Specifically, the simulation system are very useful for decision making by construction managers to select the optimum equipment and construction method with a better understanding for safety and cost-saving.
        4,000원
        97.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        When evaluating effectiveness of a R&D program, there is a tendency to simply compare the performances of the beneficiaries before and after the program or to compare the differences in the performances of the beneficiaries and the non-beneficiaries before-after the program. However, these ways of evaluating effectiveness of a program have some problems because they can not differentiate between complement effect, which facilitates corporate R&D investment, and substitute effect, which, literally, substitutes corporate R&D investment. Therefore, these problems could bring about wrong policies concerning R&D programs.In this paper, a new approach using path analysis is suggested as a means to overcome these problems and it is utilized, as an application, to evaluate the effectiveness of Plant Engineering Program conducted by Ministry of Trade, Industry & Energy, Korea. First, the direct impact of government R&D investment on corporate R&D investment is analyzed, through which it is identified which of crowding-in effect (complement effect) and crowding-out effect (substitute effect) is dominant. Next, the direct effect of government R&D investment on corporate performance and the direct effect of corporate R&D investment on corporate performance is analyzed respectively. Finally, by combining the two previous analysis, the total effect of government R&D investment on corporate performance is identified.As a result, it turns out that, in Plant Engineering Program, crowding-in effect is more dominant than crowding-out effect and that Plant Engineering Program has definitely positive effect on the beneficiary in terms of corporate performance indirectly and directly.
        4,000원
        100.
        2017.04 구독 인증기관 무료, 개인회원 유료
        SSG(self-healing smart grouting) method, has the characteristics such as an improvement of durability and waterproofing, prevention of leaching and pollution. In this study, several tests were performed such as gel-time measurement, uniaxial compression test, permeability test, chemical resistance test to compare the engineering properties of SSG with the other chemical grouting method(LW, SGR). As results of tests, the SSG method has low possibility of groundwater and ground pollution caused by leaching, furthermore, it has advantages like long/short term waterproofing, strength and durability. Therefore the SSG method can be applicable in the fields as an alternative method where is the problems of existing chemical grouting method.
        3,000원
        1 2 3 4 5