• Journal of The Korean Association For Science Education
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• v.32 no.4
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• pp.775-788
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• 2012

This study was done at a scientific camp sponsored by Nara Women's University Secondary School, Japan. In this school, $10^{th}$ grade students from 4 East Asian countries: Korea, Japan, Taiwan, and Singapore, participated. We made a research on students' perceptions about nuclear energy. Sample populations include 77 students in total, with 12 Korean, 46 Japanese, 9 Taiwanese and 10 Singaporean students. Overall perceptions comparison about nuclear energy shows average values from the order of highest Korea, Taiwan, Singapore, and to lowest, Japan. We implemented a T-test to identify perception differences about nuclear energy, with one group that include 3 countries (Korea, Taiwan and Singapore) and another group that includes all the Japanese students. T-test results of perceptions about nuclear energy shows students from the 3 countries of Korea, Taiwan and Singapore having higher average than Japanese students. (p<.05). Korean average scores regarding overall perceptions about nuclear energy show as the highest in all 4 East Asian countries and also highest in all subcategories. On the contrary in Japan, they have lower and negative perceptions of nuclear energy. In spite of these facts, perceptions of Japanese students about nuclear energy seem lowest and negative mainly because of the recent Fukushima nuclear power plant disaster, caused by the tsunami and its subsequent damages and fears of radiation leaks, etc. This shows that negative information about future disasters and its resulting damages like the Chernobyl nuclear accident could influence more on people's risk perception than general information like nuclear energy-related technologies or the news that the plant is operating normally, etc. Even if the possibility of this kind of accident is very low, just one accident could bring abnormal risks to technology itself. This strong signal makes negative image and strengthens its perceptions to the people. This could bring a stigma about nuclear energy. This study shows that Government's policy about the highest priority for nuclear energy safety is most important. As long as such perception and decision are fixed, we found that it might not be easy to get changed again because they were already fortified and maintained.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.93-98
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• 2019

The purpose of this study was to identify and analyze the rate of change of air respirator consumption based on field fire fighting activities, The results of the experiment are as follows. The mean air consumption of the Five subjects was $15.56{\ell}/min$ when standing still, $32.43{\ell}/min$ when walking with normal pace, $43.07{\ell}/min$ when the fire hoses was expanded and arranged, $55.28{\ell}/min$ when climbing stairs, The situation of running up the stairs and hitting the hammer continuously increases to $127.14{\ell}/min$, which means that the consumption of air increases according to the energy consumption. Despite being the oldest, Experimental subject A was $13.23{\ell}/min$ when standing still, $29.33{\ell}/min$ when walking normally, and $41.08{\ell}/min$ when the fire hose was deployed and arranged. This is a result of familiarity with deep and slow breathing methods. The average respiratory use rate of subjects D was $63.58{\ell}/min$. The reason for this is that obesity seems to increase the air consumption, and it is considered that the physical strength is exhausted by the action of the hammer, which has a greater influence on the increase of air consumption. The subject E had significantly lower air respiratory use rate of $49.90{\ell}/min$. The reason for this is that the age of E is the youngest among the subjects, and it is presumed that it possesses strong physical strength.

• Journal of the Korean Chemical Society
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• v.57 no.4
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• pp.432-438
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• 2013

We report a contact angle goniometer that can be easily assembled and used in high school and general chemistry experiments. It consists of an LED flash, a sample stand, and a camera fixed on an optical bread board, and the sample area is covered to block light from outside with a box with holes on both sides. ImageJ, free image analyzing software and a JAVA plugin (Drop_analysis) were used to determine the contact angle of liquid drop resting on solid surface. The contact angles of various liquids were successfully measured on various surfaces. The solid surface energies have also been determined using the Owen-Wendt method from the contact angles of $H_2O$ and $CH_2I_2$. The results reasonably agree with the previously reported values, showing the surface characteristics and modification as well as the dispersive and polar contributions. These contact angle goniometer and method for determination of the contact angle and surface energy can be applied to observation of various surface properties including wettability, hydrophilicity, and water repelling. Students can learn how the surface properties are related to the intermolecular interactions and gain experience about the equilibrium between the related forces, optics, and mathematical derivations.

• Journal of Technology Innovation
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• v.21 no.1
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• pp.303-330
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• 2013

Korea has started new value creation which is the post catch-up innovation system from the catch-up innovation. Post catch-up innovation system is becoming the main R&D issue for Korea and is needed for the new concept of R&D management and planning frame. This study posed questionnaires : how to promote the knowledge creation in technology planning and what the role of organizational learning in the technology planning is. This paper suggests the relationship of success factors of knowledge creation in technology planning which is organized and operated by experts with different background. Based on the prior research on organizational learning, communications and collaborative interactions, four hypotheses that factors of knowledge creation in technology planning have positive relationship with organizational learning are extracted. This study adopts Structural Equation Modeling(SEM) to analyze the relationship between organizational learning and successful technology planning. The approach based on organizational learning and interaction will be useful for constructing the planning framework in the era of post catch-up innovation. This paper, therefore, suggests the possibility of new theoretical development and new research agenda.

• International Journal of Highway Engineering
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• v.6 no.1 s.19
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• pp.47-56
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• 2004

To determine the pure bond strength between substrate and its overlayed concrete material, a direct pull-off test method was introduced by using a bi-material cylinder with which a penny-shaped crack was mountained at its interface. First, to evaluate the stress magnification or concentration at the interface, the energy release rates of a penny-shaped interface crack in remote tension loading on a bi-material cylinder were determined in terms of different modulus ratios and undonded area ratios(crack ratios) using a commercial finite element program. Then the energy release rates were calibrated as non-dimensional values in consideration of structural dimensions and applied forces. And to evaluate whether this new pull-off test method gives sound test results, three different sizes of unbended area ratios were incorporated along their interface in bi-material cylinders(sulphur polymer concrete + old concrete). Test results showed that all specimens were broken off at their interfaces as intended. Also the FEM analyses and test results indicated that a bi-material specimen with unbended area ratio of 0.4$\sim$0.6 is suitable for best accurate testing.

• Journal of Korea Port Economic Association
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• v.26 no.4
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• pp.329-353
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• 2010

This paper deal with government logistics policy in related low carbon in China. The government policy of promoting low-carbon way is more dependent on the top-down enforcement rather than voluntary market principles. It will succeeded in transforming the environment-friendly image, to focus on creating a mindset the company can go on voluntary carbon-reduction. The three factors of low-carbon economy and the new energy and industrial development policy is technology and funding, and that most of the government's policy has a crucial role. Due to the nature of the Chinese economy, government policies impact on the development of the industry is very important, and even for China's industrial restructuring of the logistics industry in the areas of government policy support for green economic growth, its role is expected to be very large. In Future, Chinese government will promote low carbon policies through the optimization of the logistics network to reduce energy waste, pursue the low carbon-reduction of logistics machinery and equipment, and develop an mode to appropriate demand for green low-carbon economic growth.

• JOURNAL OF ELECTRICAL WORLD
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• s.286
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• pp.64-69
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• 2000

20세기에 있어서의 비약하는 산업계의 주축으로서 철강시장은 급속히 확대되었고 그와 더불어 신기술의 개발과 도입에서도 선도적 역할을 다하여 왔다. 특히 이 4반세기는 반도체기술의 진보와 함께 컴퓨터, 플랜트 컨트롤러, 드라이브 시스템 등 전기제품은 비약적인 진화를 이루어 왔다. 현재는 중국$\cdot$아시아$\cdot$남미를 중심으로 철강제품의 수요가 증가하여 설비투자도 확대되고 있다. 그러나 북미$\cdot$유럽$\cdot$일본에서는 생산능력과 수요와의 사이에 수급공백이 있어 이전과 같은 시장만큼의 신장은 기대할 수 없는 실정이다. 이와 같은 상황하에서 철강유저의 투자목적을 합리화$\cdot$성력화$\cdot$제품품질의 향상에 두고 있어, 미쓰비시전기는 ''경쟁력 있는 제품을 만들기와 총투자코스트의 최소화''를 서포트하는 제철플랜트용 전기제품의 제공을 지향하여, 그림에 표시하는 것과 같은 4개의 어프로치로 이에 대응하고 있다. 고품질화와 자동화에 대하여는 종래의 품질제어를 능가하는 초안정화 시스템의 적용, 프로세스의 이상 검지와 자동복구에 의한 완전 노터치 오퍼레이션의 실현, 인텔리전트 센서에 의한 프로세스의 가시화로 오퍼레이터가 최종판단을 용이하고 정확하게 할 수 있는 환경을 제공한다. 고효율화$\cdot$에너지 사용합리화에 대하여는 고역률 전원을 추구하여 고효율 드라이브장치와 모터를 제공한다. 글로벌 스탠더드화에의 대응으로서는 네트워크의 오픈화에 의한 멀티벤더 환경, 범용 하드웨어에 의한 오픈 HMI(Human Machine Interface)을 제공하고 있다. 플랜트의 신속한 가동과 리모트 메인터넌스 환경을 실현하기 위하여 플랜트 시뮬레이션 시험의 실시로 공장출하 품질의 향상을 도모한다. 또한 연구센터로부터의 원격감시와 트러블해석 서포트를 쉽게 할 수가 있다. 나아가 최근에는 급격한 기세로 신장되어 온 멀티미디어 기술, 인터넷 기술, 인트라넷 기술, 모바일단말, 화상압축기술 등에 의하여 원격집중감시, 현장과 중앙 쌍방향 협조보수작업, 버추얼 리얼리티 응용시스템이 현실화 되고있는 실정이다. 이들 IT(Information Technology)솔류션은 금후의 제철플랜트의 시스템을 크게 바꾸어 나가는 것은 물론 사업 경쟁력 강화의 키 테크놀로지가 될 것이다. 앞으로 미쓰비시전기는 제철플랜트에 대하여 유저니즈를 IT 솔루션으로 전개, 제공해 나가고자 한다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.3
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• pp.116-129
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• 2000

The interaction of incident monochromatic waves with a tensioned, flexible, circular membrane submerged horizontally below free surface is investigated in the frame of three-dimensional linear hydro-elastic theory. The velocity potential is split into two parts i.e. the diffraction potential representing the scattering of incident waves by a rigid circular disk and the radiation potential describing motion induced waves by elastic responses of flexible membrane. The fluid domain is divided into three regions, and the diffraction and radiation potentials in each region are expressed by the Fourier Bessel series. The displacement of circular membrane is expanded with a set of natural functions, which satisfy the membrane equation of motion and boundary conditions. The unknown coefficients in each region are determined by applying the continuity of pressure and normal velocity at the matching boundaries. The results show that various types of wave focusing are possible by controlling the size, submergence depth, and tension of membrane.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.5
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• pp.343-354
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• 2020

Bi-stable mechanism is a system that has two different stable equilibrium positions within its range of motion. It has an ability to stay in two different positions without external power input and despite small disturbances. One of the most bi-stable applied mechanism is a morphing system, such as deployable structures, switch systems, and robot grippers. However, due to the complexity of mechanism and limitation of structure configuration, it is difficult to apply on a morphing system with rotating link mechanism. In this paper, an implementation method of rotational bi-stable mechanism using cylindrical permanent magnets is proposed. The magnetic field and the magnetic force were calculated from electromagnet model of the cylindrical permanent magnet. Based on the model, the force relation between two links containing the cylindrical permanent magnets was estimated. An array of cylindrical permanent magnets was selected for symmetric bi-stability, and an experiment on the link structure with the proposed bi-stable mechanism was performed to investigate the stability against a external torque.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.83-83
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• 2011

나노섬유는 마이크로 섬유에 비해 $10^3$배 정도의 넓은 표면적을 가지며, 다른 섬유와 비교하여 유연성, 투습성과 같은 특성이 우수하다. 나노섬유의 제조방법은 여러 가지가 있으나, 상용화의 가능성, 적용 고분자의 다양성, 제조공정의 단순성, 다양한 제품기술에의 응용성 등을 고려하여 선택하여야 한다. 나노섬유의 제조기술은 방법에 따라 전기방사, 복합방사, 멜트블로운 공정, 에어레이드 공정, 습식 공정 등으로 나눌 수 있다. 전기방사 등 나노섬유를 대량생산하여 상용화하려는 노력을 지속적으로 하고 있으나 나노섬유의 염색가공에 관련되어 기술적 한계로 제품전개에 많은 어려움을 겪고 있다. 그리하여 본 연구에서는 나노섬유 단독으로 제품화하기에는 강도 등의 문제로 PET에 워터펀칭한 복합소재로 개발하여 900nm 이하의 나노섬유에 대한 최적의 날염조건과 현장적용 생산기술을 개발하고자 하였다. 나노섬유 복합소재에 대하여 Brown, Red, Blue, Black 색상의 안료와 Urethane, Rubber, Acrylic, Eco Binder를 사용하여 날염 실험하였으며, 최적의 조건으로 현장생산에 적용하여 생산하였다. 안료의 고착성을 높여 날염성과 염색견뢰도를 증진시키기 위하여 원적외선 열처리기를 개발하여 현장생산에 접목시켰다. 원적외선 열처리기는 벙커C유 또는 가스 등을 사용하는 텐터나 증열기와는 다르게 전기를 에너지원으로 하여 원적외선 램프를 이용한 건열시스템의 형태로 저공해 및 그린 형태의 열처리기 시스템으로, 섬유에 대한 원적외선의 조사거리, 원적외선 램프의 간격, 적용 온도, 원단이송 속도 등에 따른 최적의 원적외선 열처리기 날염조건을 설정하였다. 바인더에 따른 날염성은 우레탄계 바인더를 사용하였을 경우에 가장 선명하고 깊은 색상을 보였으며, 아크릴계 바인더의 경우가 가장 낮은 색상을 보였으며 염색견뢰도는 대체적으로 양호한 결과를 얻었다. 그리고, 최근 환경적인 추세에 맞추어 에코 바인더를 사용하여 날염한 결과 염색성과 내구성 등은 우레탄계와 아크릴계 바인더의 중간 정도의 결과를 보였다.