• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.33-34
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• 2000

The effect of $Y^{3+}$ addition to $SrTiO_3:Pr^{3+}$ on the photoluminescence and cathodoluminescence was studied. We discovered that light emitting levels of $Pr^{3+}$ vary by addition of $Y^{3+}$. In $(Sr_{1-x}Y_x)TiO_3:Pr^{3+}$, both the green and red emission are discovered while the red emission prevails in $Sr(Ti_{1-x}Y_x)O_3:Pr^{3+}$ . $Sr(Ti_{1-x}Y_x)O_3:Pr^{3+}$ shows enhancement of red emission by two kinds of enhancement process.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.9
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• pp.434-437
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• 2001

ZnSe, ZnSe:Ho/sup 3+/, Mg/sub x/Zn/sub 1-x/Se and Mg/sub x/Zn/sub 1-x/Se:Ho/sup 3+/ crystals were grown by the chemical transport reaction method. The crystal structures and optical energy band gaps of the single crystals were investigated. Their photoluminescence(PL) spectra were measured at 10 [K]. Sharp emission peaks in the blue-green wavelength range and broad emission peaks in the yellow-red wavelength range were observed. The single crystals doped with 1.0 [mol%] of holmium did not show the sharp emission peaks because of defects which were thought to be originated to the holmium dopant.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2175-2180
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• 2008

Oxy-fuel combustion has been gaining its significance as a means of migrating the green house effects. Some experimental measurements were conducted to investigate the characteristics of oxy-fuel combustion and to aid a fundamental design of a lab-scale oxy-fuel combustor with a coaxial burner. CO emission was measured along the combustor centerline while combustion of methane and oxygen diluted by CO2 took place. Substitution of CO2 with N2 indicates a possibility that some CO is formed by dissociation of CO2. Some parametric tests were also performed to see the mixing effects of reactant gases on CO emission by changing the gas injection velocity at the burner nozzles with various heat loads. The overall results indicate that CO emission was reduced when the reactants are injected at higher velocities of similar magnitude.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.366-366
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• 2018

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1013-1016
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• 2005

ZnO nanostructure was fabricated by catalyst-free method using Zn powder in air. The growth temperature was controlled from 450$^{\circ}$C to 600$^{\circ}$C, and the structural and optical properties were investigated by scanning electron microscopy (SEM), photoluminescence (PL), energy dispersive X-ray spectroscopy (EDX) and cathodoluminescence (CL). From all samples both ZnO tetrapods and clusters were observed. No significant dispersion was observed from the ZnO tetrapods, however, ZnO clusters show considerable change in density and size. From the EDX results, atomic composition difference was found. The clusters have O-deficiencies, while tetrapods have stoichiometric composition. Strong luminescence was observed at room temperature. From room temperature PL, UV emission at 380 nm and green emission at 500 nm were observed, and the intensity ratio ($I_{uv}/I_{green}$) increased as growth temperature increases. CL measurements show that the UV emission is closely related with tetrapods and the green emission is dominated from the clusters.

• KIEAE Journal
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• v.11 no.5
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• pp.3-12
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• 2011

Industrialization and development of technology satisfied various humanly needs and lay the basis of numerous benefit and profit. New technologies like these mostly required large amounts of fossil Fuel, Fossil energy depletion rate was increasing rapidly. However, technical development for Human race required absolute sacrifice of the environment. Especially, 'City' which had been focused as stage of human activities, allowed to continue to have fossil energy dependent activities, and it shows in many data that the city is responsible for the 75-80% of the green house gas by human. In order to solve the problem relating climate changes and energy, European countries already made progress studies on many of the low carbon green city and pilot case construction. Especially, Germany, Austria, Holland, Sweden who had been playing leader role on environmental awareness and ecological concept, are actively constructing low carbon green city project based on Ecological city planning scheme. These projects positively utilize planning scheme that limits carbon emission using Urban Metabolism concept. Therefore, throughout this study, I would like to present planning and direction of future domestic low carbon green city by analyzing theories relative theories and best practices in Europe.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.4
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• pp.42-50
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• 2001

In this paper, the reduction of CO₂ gas emission and exhaust gas emission by using the shift of coastal transport from land transport for import-export container cargo was proposed. At first, the domestic CO₂ gas emission, exhaust gas emission and the transportation of import-export container cargo are investigated. And also, we investigated the reduction of CO₂ gas emission and exhaust gas emission by the shift of coastal transport from land transport for the transportation of import-export container cargo between Kyongin area and Pusan Port. Finally, the change of NOx gas emission due to the change of the share of coastal transportation and using the 320TEU container ship are investigated. The research results show that the shift of coastal transport from land transport was effective to reduce the CO₂ gas emission and exhaust gas emission.

• Proceedings of the Safety Management and Science Conference
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• 2009.11a
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• pp.405-409
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• 2009

Most countries have been focused on the CDM(Clean Development Mechanism). According to Wikipedia, the free encyclopedia, CDM is an arrangement under the Kyoto Protocol allowing industrialized countries with a greenhouse gas reduction commitment to invest in projects that reduce emissions in developing countries as an alternative to more expensive emission reductions in their own countries. There are many environmental problems which resulted from development of IT field. The main objective of this paper is to find an effective methodology as an initial stage for applications of green IT in a real life. Therefore this paper addresses worldwide reviews on green IT products.

• Journal of the Korean Ceramic Society
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• v.48 no.3
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• pp.251-256
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• 2011

The luminescence properties of polycrystalline ZnO annealed in reducing ambience ($H_2/N_2$) have been studied. An effective quenching of green luminescence with enhanced UV emission from polycrystalline ZnO is observed for the reduced ZnO. The variations of the UV and green luminescence band upon reduction treatment are investigated as a function of temperature in the range between 20 and 300 K. Upon annealing treatment in reducing ambience, the optical quality of polycrystalline ZnO is improved. The UV to green intensity ratio of sintered ZnO approaches close to zero (~0.05). However, this ratio reaches more than 13 at room temperature for polycrystalline ZnO annealed at $800^{\circ}C$ in reducing ambience. Furthermore, the full width at half maximum (FWHM) of the UV band of polycrystalline ZnO is reduced compared to unannealed polycrystalline ZnO. Electron paramagnetic resonance (EPR) measurements clearly show that there is no direct correlation between the green luminescence and oxygen vacancy concentration for reduced polycrystalline ZnO.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.2
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• pp.112-121
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• 2010

With the global climate changes, a global concerns on building energy uses and $CO_2$ emission to improve the environment friendly has been increasingly growing. To achieve this global goal, the Korea government has been seeking an environment-friendly and sustainable development. As the results, the government started Green Building Certification Criteria system. however the certificate system has still been at the basic stage. To upgrade and advance it's level, it's necessary to identify the current status. This study aims to pick out the items requiring improvement for the Ecology of Education Facilities. We expect that the results of this study will be helpful for the next design works of certificate system.