• Journal of the Korean Electrochemical Society
• /
• v.4 no.2
• /
• pp.70-76
• /
• 2001

The present work describes the capabilities of laser beam deflection (LBD) technique for the analysis of the stresses developed during hydrogen diffusion through Pd foil electrode. First, we explain briefly the elasto-diffusive (Gorsky effect) and diffusion-elastic phenomena. A model for the diffusion-elastic phenomenon is theoretically derived from the solution of the Fick's equation for given initial and boundary conditions, Vegard's second law and Hooke's law. Second, we introduce how to apply the principle of LBD technique to the study on the stresses generated during hydrogen diffusion. From the comparison of the deflection transients numerically calculated with those experimentally measured, we finally discuss the change in the tensile deflection with time in terms of hydrogen concentration profile transient and hydrogen diffusivity.

• Investigative Magnetic Resonance Imaging
• /
• v.11 no.2
• /
• pp.110-118
• /
• 2007

Purpose: The objective of this work to construct eigenvalue maps that have information of magnitude of three primary diffusion directions using diffusion tensor images. Materials and Methods: To construct eigenvalue maps, we used a 3.0T MRI scanner. We also compared the Moore-Penrose pseudo-inverse matrix method and the SVD (single value decomposition) method to calculate magnitude of three primary diffusion directions. Eigenvalue maps were constructed by calculating of magnitude of three primary diffusion directions. We did investigate the relationship between eigenvalue maps and fractional anisotropy map. Results: Using Diffusion Tensor Images by diffusion tensor imaging sequence, we did construct eigenvalue maps of three primary diffusion directions. Comparison between eigenvalue maps and Fractional Anisotropy map shows what is difference of Fractional Anisotropy value in brain anatomy. Furthermore, through the simulation of variable eigenvalues, we confirmed changes of Fractional Anisotropy values by variable eigenvalues. And Fractional anisotropy was not determined by magnitude of each primary diffusion direction, but it was determined by combination of each primary diffusion direction. Conclusion: By construction of eigenvalue maps, we can confirm what is the reason of fractional anisotropy variation by measurement the magnitude of three primary diffusion directions on lesion of brain white matter, using eigenvalue maps and fractional anisotropy map.

• Archives of design research
• /
• v.18 no.1 s.59
• /
• pp.81-90
• /
• 2005

Universal Design is comprised of three main concepts known as barrier-free, adaptive and life-span design. It does not focus on accessibility for the disabled, but rather expands its breadth to the comfortable use and easy access in ail physical environments and facilities. In this study, the researcher views the present and future of universal design through the cases of kitchen design. Based on the market changes in design guidelines and the changes of time uncovered from past studies, this researcher suggests that universal design would develop through mass customization for personalized use, application of new technology and consideration of psychological aspects. Additionally, for the diffusion of universal design appropriate solution in economic cost problem, social recognition and conversion of problem cognizance in designing is needed. In Korea design models of universal design concepts are not yet in production over various fields. In order to develop and study universal design which suits our country, cultural and regional characteristics should be considered as well as physical, perceptual, psychological aspects.

• Journal of Korean Library and Information Science Society
• /
• v.44 no.3
• /
• pp.5-27
• /
• 2013

The purpose of this study is to examine the characteristics and continuity of 'One Book, One City' community reading campaign in the U.S.A. An analysis of 584 'One Book' projects registered in the Library of Congress, the Center for the Books shows that this innovative model of reading campaign has been diffused through three stages: the beginning(1998-2001), the growth (2002-2006), and the second take-off(2007-present). The stability of more than fifty 'One Book' projects was confirmed and the continuing diffusion of 'One Book' model through 'The Big Read' Initiative and some projects' attempt to try new directions seem worth observing.

• Journal of Energy Engineering
• /
• v.23 no.3
• /
• pp.7-12
• /
• 2014

This paper suggest mandatory target predestinator of natural gas wholesale and retail provider will set appropriate target. To analysis natural gas energy saving trend forecast, reduce natural gas forecast and using technology and forecast analysis for equipment is draw based on result of developing tool that more detailed gas field. Also this paper calculate effect on energy saving through various scenarios, efficiency consideration of gas equipment and subsidy condition.

• Journal of Korean Library and Information Science Society
• /
• v.50 no.2
• /
• pp.237-260
• /
• 2019

In this study, the use statistics by type of data in the A university of a Institutional Repository(IR) with exponential growth in usage and the trend of changes in the access path for users to access A-IR were analyzed. In particular, it was verified that securing various exposure paths contributed to the spread of A-IR by focusing on the change in the approach path, and also confirmed that the method of communication between the ages, such as SNS, is used as the approach path of A-IR. Through this process, the company was planning to suggest the direction of operation, including diversification of exposure paths that activate the institutional repository.

• Journal of Energy Engineering
• /
• v.17 no.1
• /
• pp.31-37
• /
• 2008

At present, the target amount of demand-side management and investment cost of EE (Energy Efficiency) program, which consists of high-efficiency appliances, has been estimated simply by the diffusion function based on the real historical data in the past or last year. In the internal and external condition, the penetration amount of each appliance has been estimated by Bass diffusion model which is expressed by time and three coefficients. And enough acquisition of real historical data is necessary for reasonable estimation of coefficients. In energy efficiency, to estimate the target amount of demand-side management, the penetration amount of each appliance should be primarily forecasted by Bass diffusion model in Korea. On going programs, however, lightings, inverters, vending machine and motors have a insufficient real historical data which is a essential condition to forecast the penetration amount using a Bass diffusion model due to the short period of program progress. In other words, the forecast of penetration amount may not be exact, so that it is necessary for the method of forecast to apply improvement of method. In this paper, the penetration amount of high-efficiency appliances is forecasted by Bass, virtual Bass, Logistic and Lawrence & Lawton diffusion models to analyze the diffusion progress. And also, by statistic standards, each penetration is compared with historical data for model suitability by characteristic of each appliance. Based on the these result, in the forecast of penetration amount by diffusion model, the reason for error occurrence caused by simple application of diffusion model and preferences of each diffusion model far a characteristic of data are analyzed.

• Proceedings of the KOR-KST Conference
• /
• 1998.10b
• /
• pp.452-452
• /
• 1998

1. 세계 항공시장의 동향 ○ 항공운송산업의 규제완화 및 항공자유화 추세의 확산 -78년 미국의 규제완화 이후 유럽, 대양주, 아시아 등으로 파급 ○ 미국의 항공자유의 정책(Open skies Policy)은 EU의 역대 완전자유화와 함께 세계항공시장의 자유화 촉진 ○ 항공사간 전략적 제휴의 확산 -British Connection, Star Alliance, Southern Comfort, Dutch Treat 등 4대 범세계적 제휴가 결성 또는 추진 중. 2. 우리나라 항공운송산업의 현황 ○ 세계 10위권 항공운송국가로 성장 -화물 세계5위, 여객 11위(97 ICAO통계) -김포공항은 97년 중 36.5백만명 처리로 세계9위 차지 ○ IMF체계의 영향과 경영수지 변화 추이 -98년 내국인 출국자는 감소하였으나, 외국인 관광객은 증가(10.8%) * 98. 1∼8전년대비 수송수요 국제선 17%, 국내선 26% 감소 -97년 양 항공사 적자규모 약 4,000억원으로 대폭 증가, 98상반기 회복추세. 3. 21세기 국제항공정책 방향 ○ 적극적인 항공시장 개방정책 추진과 역내 주요도시간 셔틀화 ○ 세계 주요 항공사와의 전략적 제휴를 지원하여 세계항공시장에서의 경쟁력 제고 * KAL-이, AAR-AA -인천국제공항의 HUB화 추진(민간 경영기법 도입, 항공개방정책 등) ○ 항공사가 최적의 노선망과 경제성을 갖도록 하는 적정 성장방안 강구 ○ 선진국 수준의 획기적 항공안정 체계 확립

• Korea journal of population studies
• /
• v.28 no.2
• /
• pp.183-203
• /
• 2005

Over the past four decades reproductive behavior has changed rapidly in much of the developing countries. The average total fertility rate has fallen by half from six or more to near three today. Between 1960 and 2000 the largest fertility decline occurred in Asia and Latin America. The mortality rate has decreased in most developing countries. The purpose of this study is to review the pattern of demographic transition in developing countries. At first, this study focuses on the regional fertility transition. In Africa, the total fertility rate has decreased from 6.59 to 4.85 between 1960 and 2000. However, the rate has rapidly fallen from 5.76 to 2.34 in East Asia. The same pattern is found in Latin America. The mortality rate has also decreased in most of developing countries. It is also interesting to find that there is a clear difference among developing countries. In terms of crude death rate, Latin American countries show the lowest rate, while African countries remain still high rate. The study also shows the relationship between socioeconomic indicators and fertility/mortality in developing countries. The result supports the hypothesized relationship between education and fertility. However, the effects of urbanization and income on fertility do not show consistent result. About mortality rate, however, the study shows the significant relationship between urbanization and infant mortality rate, between income and mortality. The study finally emphasizes that we should include 'AIDS' in the study of mortality in African countries.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.6
• /
• pp.780-787
• /
• 2019

As a carbon-free, green growth alternative, internal and external interest in hydrogen energy and technology is growing. Hydrogen was added to co-axial methane, methane-propane, and methane-propane-ethane diffusion flames, which are the main ingredients of LNG, to evaluate its effect on flame formation and combustion products. The variation in combustion products produced by adding hydrogen gradually to diffusion pyrolysis at room temperature and normal pressure conditions was observed experimentally by using a gas analyzer, and the shape of diffusion pyrolysis was observed step by step using a digital camera. The experimental results showed that the production volume of nitrogen oxides tended to increase and became close to linear as hydrogen was added to the diffusion pyrotechnic. This is because the relatively high temperature of heat insulation and fast combustion speed of hydrogen facilitated the production of thermal NOx. On the other hand, CO2 production tended to decrease as hydrogen was added to reduce the overall carbon ratio contained in the mixed diffusion flame of methane, methane-propane, and methane-ethane-propane. This means that the mixed fuel use of LNG-hydrogen in ships may potentially reduce emissions of CO2, a greenhouse gas.