• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.539-541
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• 2007

유채유를 이용한 바이오디젤의 실질적인 가치는 배럴당 355,000원으로, 현재의 가격은 평가절하되어 있으며 에머지 생산비율(EYR)은 1.27으로서 석유의 8.4에 비하여 효율이 낮아 대체에너지로서의 경쟁력은 없으나 1보다 높아 에너지 소비 절감의 효과는 있다. 환경부하비율(ELR)은 2.46으로 수력발전의 3.3과 Bioethanol의 7.7보다 낮아 환경에 미치는 영향은 작은 것으로 나타났다. 에머지 지속가능성지수(ESI)는 0.52로 재생불가능한 에너지와 외부에서 구입한 재화와 용역에 대한 의존도가 높으므로 지속성이 낮은 것으로 나타났다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.135-136
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• 2000

1970년대 지구적 차원의 에너지 부족, 인플레이션, 과도한 경제성장 그리고 환경보전에 대한 관심고조는 자연환경과 경제활동에 대한 지금까지의 양상과는 다른 인식전환을 요구하였다. 1992년 Rome Club에서 발표된 "Limits to Growth"에서 인류에 대한 위기를 지적, 우리의 미래에 대한 Sustainability의 개념은 새로운 이슈가 되었다. 1992년 $\ulcorner$리우환경선언$\lrcorner$ 에서 앞으로 인류가 나아가야만 하는 미래의 방향으로 ESSD(Environmentally Sound and Sustainable Development)를 제시하였다. 한국의 경우, 환경에 대한 고려는 최근까지도 정부의 경제성장 우선 정책에 의해서 뒷전으로 밀려나 있었다. (중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.814-817
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• 2004

It is a challenging task to make the paraplegic to walk with out the assist of the caregiver. So, we have developed various type of gait orthosis for paraplegic during the five years lately. The purpose of this study ultimately is energy consumption test of serveral type gait orthosis for developing the high efficiency gait orthosis. From the experimental results, the oxygen consumption rate were 6.9$\pm$3.3ml/kg in RGO gait, 5.3$\pm$1.3ml/kg in PGO, and 6.2$\pm$3ml/kg in HGO gait. The maximum hip flexion angle were 16$^{\circ}$ in RGO , 15$^{\circ}$ in PGO, and 47.5$^{\circ}$. in HGO. As a result It was found that. Hybrid Gait Orthosis need high energy consumption more than PGO for walking, but it is small weight and strengthened muscle.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.147-152
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• 2012

Supply chain including transportation expend the 21% of domestic energy consumption. It is necessary to diminish the excess energy usage at entire supply chain. This paper deals with the application of MFCA(Material Flow Cost Accounting) for SCM to save energy consumption. We construct the material center corresponding to each logistics function in order to apply the MFCA for GCM(Green Chain Management). We also construct the MFCA framework which consists of MFCA Database Management, MFCA Visualization, GCM Data Integration, GCM Data Tracking, and MFCA Data Predict & Assignment. We expect to help determining the range of logistics function to apply the MFCA for GCM.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.421-424
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• 2006

종래의 개발은 양면성을 가지고 있다. 하나는 개발로 인한 경제적 효율성과 편리성 부분이고, 다른 하나는 그러한 개발로 인한 자연훼손 및 생태계 파괴이다. 이로 인해 개발과 보전은 양립할 수 없는 상반적인 개념으로 받아들여져 왔고, 개발론과 보전론의 대립적 구도가 지속되어 왔다. 우리나라는 국토의 65% 이상이 산지이기 때문에 산지의 부분적 개발은 피할 수 없는 사회적 요구인 동시에, 산지는 자연생태계의 보고로서 생태계 보전이 필수적인 지역이다. 이러한 산지 개발과 보전에 대한 상반적 이해를 통합하여 자연과 인간의 공생체계를 갖추기 위해서는 인간중심의 사고에서 탈피하여 사람과 생태계 그리고 자연을 하나로 보는 총체적인 측면에서 접근하는 새로운 패러다임이 설정되어야 한다. 본 연구에서는 산지의 정량적인 가치를 평가하기 위해 시 공간적으로 다양한 인자들에 대해 시스템적인 관점에서 그 중요성을 고려하고자 하는 에머지 개념을 통해 산지 본래의 가치를 평가하였다. 에머지 개념은 그 동안 생태계가치평가, 개발사업의 편익-비용평가, 환경수용력 평가, 개발대안 평가, 환경계정, 환경훼손 소송관련 비용 평가 등에 적용되었다. 이러한 에머지 개념을 이용한 평가 방법을 통한 의사결정이 이루어지면 산지뿐만이 아닌 생태계의 지속가능한 이용을 실현하기 위한 적절한 정책의 선택과 이의 이행 실효성을 높일 수 있을 것으로 기대되며, 자연환경 가치의 정량적 평가를 통해서 우리는 한층 더 자연환경 및 자원의 다원적 기능에 대한 자각을 할 수 있을 것으로 판단된다.

• Journal of Environmental Science International
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• v.17 no.9
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• pp.969-980
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• 2008

This research was performed to simulate shellfish production systems and sales in Gamak Bay, South Korea. To study the way the shellfish system generates maxima, a numerical model was developed to simulate the model under a control and a number of different scenarios. The program calculates the EMERGY flows by multiplying the flows of energy and materials by the appropriate solar transformity. In this study, an energy systems model was built to simulate the variation of sustainability for oyster aquaculture. The results of the simulation based on 2005 data that as oyster production yield slightly increases, money and assets increase to a steady state. When the program is run control simulation, the system reaches carrying capacity after 8 years. The simulation of models with price of purchased inputs increased with 3.5% inflation rate per year showed maximum benefit of shellfish production occurs after 6 years but amounts are less than control simulation, and then decreases slightly in money and yield results. The results with 3.5% inflation and increase of oyster price annually showed steady and slightly increase of money and yield.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.593-597
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• 1995

To measure theological properties of the starch dough, an Extrusion Capillary Viscometer(ECV) cell was self-made and attached to Instron machine(Model 1140). Apparent viscosities of corn and waxy corn starch doughs were measured and their gelatinization degrees were determined by enzymatic analysis. The effects of heating temperature on the viscosity of starch dough with $36{\sim}52%$ moisture contents were examined in terms of Arrhenius equation. The activation emergy(Ea) of the dough viscosity from the effect of heating temperatures changed from negative(-) to positive(+), as the moisture content increased from 44% to 48% in the corn starch dough and from 44% to 44% in the waxy corn starch dough.

• Journal of the Korean Regional Science Association
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• v.15 no.2
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• pp.131-153
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• 1999

Since 1980's there have been two trends that obviously developed in the would -- economics globalization and urban internationalization. China, with is reform and opening-up policy and rapid economic growth, keeps pace with these two trends. The term "International City" has no putative standard or definition. If we make an analogue of urban functional hierarchy in the world with a pyramid, the International Citiesa are the few elites on its top. The highest level international cities can be called "World City" or "Global City". In today's new international division of labor, they are diversified leading cities with control capacity on a world scale, like New York, London, and Tokyo. The secondary international cities are either diversified cities with influence and regulative functions on multinational scale or specialized cities on politics, economics, culture, or other aspects with worldwide impact. Judged by different criteria, there is no city that is qualified as International City with the exception of Hong Kong, which was returned to the P.R. of China in 1997. Nevertheless, Some favorable conditions for the development of the international city still exist in China. This country is already the sixth largest economic entity in the world, and the second largest economic entity in the world, and the second largest one if GNP estimated by ppp. Furthermore its import and export value make up for 40% of its GNP, indicating that China is repidly merging into global economy. In this 1, 2 billion-population country, the difference of economic levels between urban and rural, coastal and inland regions is so big that a few metropolises in the coastal region have the possibilities and potentials to develop into international cities regardless of rather low GNP per capita of the whole country. This article will focus on analysis from several perspectives, such as the proportion of foreign trade values in GDP, the proportion of imports and exports by foreign funded enterprises in total foreign trade value; distribution of the 500 largest foreign-funded enterprises; distribution of the 500 enterprises with largest import and export values; distrigbution of foreign computer and telecom companies with offices in China; the number of outward flights per week and the international tourists; the value of foreign capital used in cities and so on. From this analysis, it is predicted that Chinese international cities will surely emergy from the eastern coastal regions and they must be the core cities of metropolitan interlocking regions that have been formed or in the process of forming. Those international cities will arise from south to north in turn : Hong Kong-Guangzhu, Shanghai, Beijing-Tianjin, and perhaps the last one is Dalian-Shenyang. The other side of this issue is that there is a long way for the coming international cities in China except Hong Kong. At least China and these core cities must continually devote to (1) improve the regional composition of foreign capital sources. (2) improve the composition of export commodities. (3) improve the investment environment (including hard and soft environment) to attract more transnational corporations to settle. (4) deepen the reform of state-owned enterprises and establish Chinese own transnational corporations to enter the world market.ons to enter the world market.

• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.21-35
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• 1997

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-20Pd-20Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electic furace and centrifugal casting machine in Ar atmoshpere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age-hardening characteristics of the small Au-containing Ag-pPd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, emergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, I. e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the Llo type face centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affedted by the Cu concentration. In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase(L1o type) and an Agrich ${\alpha}2$ phase occurred and a discontiunous precipitation occurred at the grain boundary. Form the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}\to{\alpha}+{\alpha}2+PdCu\to{\alpha}1+{\alpha}2+PdCu$ at Pd/Cu = 1 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.