• Asia pacific journal of information systems
• /
• 제26권4호
• /
• pp.542-560
• /
• 2016

This study determines whether or not firms can achieve high productivity growth through external technology acquisition. It also identifies the key factors affecting adopting firms' productivity growth by employing the Malmquist productivity index (MPI) methodology, which features computational ease, low data dependency, and decomposition of productivity growth into technical efficiency change and technical change. Results showed that the effects of productivity growth arising from technology transfer became stronger over time. Moreover, patent transfer guaranteed firms' productivity growth, but no evidence was found that factors such as age and size could increase productivity. Finally, cultural similarity could be another factor conditioning the effectiveness of technology transfer in the productivity of adopting firms.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
• /
• pp.1199-1200
• /
• 2006

In this paper, I try to measure the electrical characteristics of PV cell for lanterns with solar simulator and simulated with PC1D software. I keep my eye on the characteristics variation of PV cell as a temperature change. Therefore, I try to increase a temperature of controlled block from $10^{\circ}C$ to $50^{\circ}C$ while measuring the PV cell. As a result, A variation caused by voltage have an effect on the efficacy of PV cell. Hence, it is an important variable when a designer plan to make a solar cell for lanterns.

• Geomechanics and Engineering
• /
• 제17권2호
• /
• pp.157-164
• /
• 2019

The effect of electrochemical modification of the physical and mechanical properties of sandstone from Paleozoic coal measure strata was investigated by means of liquid nitrogen physical adsorption, X-ray diffraction and uniaxial compressive strength (UCS) tests using purified water, 1 mol/L NaCl, 1 mol/L $CaCl_2$ and 1 mol/L $AlCl_3$ aqueous solution as electrolytes. Electrochemical corrosion of electrodes and wire leads occurred mainly in the anodic zone. After electrochemical modification, pore morphology showed little change in distribution, decrease in total pore specific surface area and volume, and increased average pore diameter. The total pore specific surface area in the anodic zone was greater than in the cathodic zone, but total pore volume was less. Mineralogical composition was unchanged by the modification. Changes in UCS were caused by a number of factors, including corrosion, weakening by aqueous solutions, and electrochemical cementation, and electrochemical cementation stronger than corrosion and weakening by aqueous solutions.

• 한국가정과교육학회지
• /
• 제34권2호
• /
• pp.95-113
• /
• 2022

본 연구의 목적은 2015 개정 교육과정에 따라 집필된 12종의 중학교 기술·가정 교과서에 나타난 '기후변화 대응 실천역량'을 분석하고 활동과제의 개선 방안을 제안하는 것이다. 분석 결과는 첫째, 교과서에 나타난 기후변화 대응 실천역량은 '기후변화 관련 지식'의 빈도가 가장 높았고 '기후변화 의사소통능력'이 가장 낮았다. 둘째, 12종의 모든 교과서가 기후변화대응 실천역량 중 '기후변화 관련 지식'을 가장 많이 다루고 있었고 그 외의 역량은 출판사별로 빈도에 차이가 있었으며 셋째, 기후변화 대응 실천역량은 가정교과 핵심개념 중 '관리'에서 가장 많이 다루어졌으며, '생애설계'에서는 전혀 다루어지지 않았다. 가정학 세부 학문별로는 의생활 영역이 가장 많았고, 가족생활 영역이 가장 적게 나타났다. 위의 분석 결과를 토대로 기후변화 대응 실천역량이 가정교과의 전반적 영역에서 다루어져야 함을 제안하였다. 본 연구는 가정교과의 기후변화 관련 기초 연구로서 의미가 있으며, 앞으로 가정과 교육을 통해 기후변화 행동을 실천할 수 있는 다양한 연구 및 교육 프로그램이 실행되기를 기대한다.

• International Journal of Automotive Technology
• /
• 제6권1호
• /
• pp.45-52
• /
• 2005

Interrupted creep tests for investigating the structural degradation during creep were conducted for a Mod.9Cr-1Mo steel in the range of stress from 71 to 167 MPa and temperature from 873 to 923 K. The change of hardness and tempered martensitic lath width was measured in grip and gauge parts of interrupted creep specimens. The lath structure was thermally stable in static conditions. However, it was not stable during creep, and the structural change was enhanced by creep strain. The relation between the change in lath width and creep strain was described quantitatively. The change in Vickers hardness was expressed by a single valued function of creep LCR(life consumption ratio). Based on the empirical relation between strain and lath width, a model was proposed to describe the relation between change in hardness and creep LCR. The comparison of the model with the empirical relation suggests that about 65% of hardness loss is due to the decrease of dislocation density accompanied by the movement of lath boundaries. The role of precipitates on subboundaries was discussed in connection with the abnormal subgrain growth appearing in low stress regime.

• 한국실내디자인학회논문집
• /
• 제25권6호
• /
• pp.15-22
• /
• 2016

Recent changes in the Korean education policies are promoting the advances in science and technology and cultivating people of convergence talent. STEAM (science, technology, engineering, art and math) educational program is Korean styled convergence program for creative competent human resources. Therefore, Therefore the aim of this study is developing convergence hand-on educational program coping with climate change for elementary school students. For development of the program, we investigated the curriculum of the elementary school about the climate change, and allocated in the creative learning standard frame. Also, we selected themes related the climate change in the curriculum and learning activity. For more effective program to build the convergence competency, we analyzed the program based on creative problem based learning process and 4 core competency(creativity, communication, convergence, caring) elements. In conclusion, the STEAM program needs to develop by school curriculum and leaner's ability. For elementary school students, the STEAM program consists with creative problem based learning process. And the convergence educational program would analyze by the creative PBL process and convergence competency elements. So, this developing program has brought the promotion of the creative convergence competent talented person for the future global environment.

• Ocean and Polar Research
• /
• 제33권4호
• /
• pp.507-516
• /
• 2011

Tropical Atmosphere Ocean/Triangle Trans-Ocean Buoy Network (TAO/TRITON) Array is the series of buoys for the international ocean research project, which is mostly supported by National Ocean and Atmosphere Administration (NOAA) and Japan Agency for Marine-Earth Science and Technology (JAMSTEC). We can determine the effect of the equatorial and Pacific Ocean conditions on global climate change from buoy array measurement data. The TAO/TRITON array comprises around 70 measurement buoys from $10^{\circ}$ north to $10^{\circ}$ south in the tropics and between Galpagos and New Guinea. NOAA maintains ATLAS buoys in the central and eastern Pacific between $165^{\circ}E$ and $95^{\circ}W$, and JAMSTEC maintains the 12 buoys in the western Pacific along $137^{\circ}E$, $147^{\circ}E$, and $156^{\circ}E$. The KA-10-03 cruise excursion provided us with a good opportunity to obtain knowledge on oceanic buoy operation and maintenance. Further, we learned advanced techniques and know-how on buoy operation and maintenance. Once we are confident with our buoy management and maintenance techniques, both KORDI and NOAA technicians may be able to help each other when needed and share available resources.

• 한국환경복원기술학회지
• /
• 제2권3호
• /
• pp.38-46
• /
• 1999

The purpose of the study is to analyze the effect of urbanization, the degree of development in urban scale and the comparative analysis of landuse change in order to construct the important basic data for establishing development direction and characterizing each city. To analyze the urban growth patterns a land cover classification using Landsat TM data was performed : 1987 and 1997 for the change detection of each land cover. The results of this study demonstrates that urban areas increased on while forest areas had decreased all over the Korean cities. Especially, in case of the analysis on landuse conversion rate, we found out that the forest areas was first changed into agricultural areas, then it is consequently developed into urban areas in most rural areas. This study concludes that the insufficiency of the number of knowledged officials in the local administration and a government official in one's charge, tight financial conditions and absence of recognition of cities' characteristics, urban development following unrefined development patterns, inappropriate urban planning and policy of metropolitan cities and the negligence of peculiar development patterns of each city.

• 한국환경복원기술학회지
• /
• 제15권2호
• /
• pp.149-162
• /
• 2012

Habitat loss and fragmentation are ongoing major anthropogenic impacts on landscapes, which can strongly affect ecosystems, populations and species. The studies on forest fragmentation have been progressed, but the studies on definition of forest fragmentation and their synthetic trend in South Korea still leaves much to be desired. Therefore we set the definition of forest fragmentation and reviewed the related papers. We can give a definition that forest fragmentation is not only a process of spatial landscape transformation, but also a process of ecosystem change by it. The trend of studies on forest fragmentation divided into two fields, landscape and ecosystem changes. Forest fragmentation caused by land change altered the composition and configuration of forest patches. Most studies related on that analyzed the change using landscape index. The effects of forest fragmentation on ecosystem subdivided into three fields : biodiversity, edge effects, and invasive species, but the studies in South Korea is short. The study on relations between forest fragmentation and ecosystem change is necessary to face the Convention on Biological Diversity in South Korea. In addition, the fundamental studies on biodiversity is important to mitigate against forest fragmentation.

• Journal of Magnetics
• /
• 제21권1호
• /
• pp.57-60
• /
• 2016

Non Destructive Testing (NDT) methods that are capable of detecting the wall thinning and defects through insulation and cladding sheets are necessary. In this study we developed a Pulsed Eddy Current (PEC) system to detect wall thinning of ferro magnetic steel pipes covered with 95 mm thick fiber glass thermal insulator and shielded with aluminum plate of thickness 0.4 mm. In order to confirm the thickness change due to wall thinning, two different sensors, a hall sensor and a search coil sensor were used as a detecting element. In both the cases, the experimental data indicates a considerable change in the detected pulse corresponding to the change in sample thickness. The thickness of the tube was made to change such as 2.5 mm, 5 mm and 8 mm from the inner surface to simulate wall thinning. Fast Fourier Transform (FFT) was calculated using window approach and the results were summarized which shows a clear identification of thickness change in the test specimen by comparing the magnitude spectra.