• Clean Technology
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• v.9 no.3
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• pp.115-124
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• 2003

Bio industry had rapidly grown up to about 32% annualy mean since '90. To overcome a trade barrier related with environmental issues, which were needed to reduce and reuse pollutants generated from the manufacturing process of product to develop and apply cleaner technology. In this paper, the usefulness of membrane process were surveyed for economical and effective treatment of waste water which were discharged from the production of polymannuronic acid. Concentration efficiencies for U/F 10k, U/F 1k, and N/F were 40%, 60%, and 80% by batch operation. Concentration efficiencies for a combination process of U/F 1k and N/F were 90% by continuous operation. There were a lot of loss of product, which could improve 25% of productivity with recovering product by introducing membrane process.

• Korean Journal of Organic Agriculture
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• v.12 no.4
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• pp.411-425
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• 2004

The aim of this experiment was to investigate the effects of applying times and dilution rates of cattle slurry with water on dry matter yields and feed values of orchard grass. Cattle slurry was applied at the rates of average nitrogen fertilizer equivalent to 150kg/ha/year in 3 cutting frequency. Significantly higher dry matter yields than that of no fertilization (7.36 ton DM/ha) were recorded in the application of diluted cattle slurry (10.74~13.54 ton DM/ha) (p<0.05). Especially, this tendency was shown with higher annual dry matter yields at the partitioned dressing times, such as at the applications for 1st and 3rd growth, 2nd and 3rd growth, and 1st, 2nd and 3rd growth respectively. The yields of annual dry matter at fertilizing phosphorus, potassium and nitrogen were higher than no fertilization as 12.42 tons per ha. However, with application of diluted cattle slurry, dry matter yields per year (11.96 ton DM/ha) were significantly higher than those of fertilizing phosphorus and potassium (7.52 ton DM/ha) (p<0.05). The efficiencies of dry matter production with mineral and cattle slurry nitrogen application (kg DM/kg N) were 32.7 and 13.4~26.9kg DM/kg N respectively. Especially, these tendencies were higher in diluted application plots than in no-diluted application plots of cattle slurry. The contents of crude protein (CP, %), neutral detergent Eber (NDF, %), acid detergent fiber (ADF, %), annual yields of CP (kg/ha) and total digestible nutrient (TDNY, kg/ha) of orchardgrass were significantly higher at the application of diluted cattle Slurry than those at non-fertilizer application (p<0.05).

• Environmental and Resource Economics Review
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• v.22 no.2
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• pp.329-365
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• 2013

The purpose of this paper is to measure economy and environment efficiencies under fossil fuel and environment regulation by countries for 2000-2009. Distinguishing 83 countries with three groups of OECD, upper-middle, and low countries, we compare four models such as environment oriented, economy-oriented, environment-economy oriented, and two-stage types, which include a desirable output, GDP and an undesirable output, pollutant together in the production possibility set. OECD countries relatively showed high economy efficiency and low environment efficiency, whereas Non-OECD countries showed high environment efficiency and low economy efficiency. OECD countries reported a higher possibility to reduce fossil fuel and $CO_2$ emission.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.955-962
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• 2005

Power efficiency, lifetime and stable manufacturing processes are the crucial parameters for the success of organic light emitting diodes (OLEDs) in display and lighting applications. Highest power efficiencies of PIN-OLEDs for all principal colours and for bottom and top emission OLED structures have been demonstrated. The PIN structure, which means the incorporation of intentionally doped charge carrier transport layer in a suitable OLED layer setup, lowers the operating voltage to achieve highest power efficiencies. Up to now the n-doping of the electron transport layer has been done by alkali metal co-deposition. This has main draw-backs in terms of manufacturability, since the handling of large amounts of pure Cs is a basic issue in production lines. Here we present in detail results on PIN-OLEDs comprising a newly developed molecular n-dopant. All the previous OLED performance data based on PIN-OLEDs with alkali metal doping could be reproduced and will be further improved in the future. Hence, for the first time, a full manufacturing compatible PIN-OLED is available.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.698-701
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• 2000

To prevent surface and underground water pollution, wastewater treatment is essential. Four bench-scale activated sludge units (10 L operational volumes) were operated at 5, 10 and $20^{\circ}C$ for evaluation of treatment efficiencies with typical wastewater from swine housing. The units were set for a 24-hour cycle. As compared to the conventional process, high removal efficiencies for organic substances, nitrogen and phosphorus in swine wastewater were obtained simultaneously with an intermittent aeration process (lAP). The NOx-N produced during an aeration period was immediately reduced to nitrogen gas (e.g. $N_2$ or $N_2O$) in the subsequent non-aeration periods, and nitrification in aeration periods occurred smoothly. Under these conditions, phosphorus removal occurred with the release of phosphorus during the non-aeration periods followed by the excess uptake of phosphorus in the activated sludge during aeration periods. It was confirmed that the lAP had a better ability to remove pollutants under both low temperatures and high nitrogen loading conditions than the ordinary method did. In addition to that, the total emission of $N_2O$ from lAP was reduced to approximately 1/50 of the conventional process for the same loading. By adopting an adequate aeration programme for individual swine wastewater treatment, this system will provide a promising means for nitrogen and phosphorus control without pH control or addition of methanol.

• Journal of Environmental Policy
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• v.11 no.1
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• pp.75-97
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• 2012

The purpose of the paper is to estimate the functions of the energy input efficiency and the energy intensity efficiency, and measure their energy efficiencies for the reduction of greenhouse gases focusing on OECD countries. The efficiency of the traditional energy intensity was rarely connected with the energy efficiencies of the stochastic frontier function. It seems that the energy efficiency by the function of energy input efficiency sensitively responds to the order of GDP, capital stock, labor, and energy input quantity as explanatory variables. In the future, we need to reduce energy quantities by the optimal mix of inputs, and pursuit low-carbon economic growth through the production of the goods consuming small energy.

• Journal of Environmental Impact Assessment
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• v.14 no.3
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• pp.109-115
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• 2005

This study was conducted to evaluate the efficiency of indoor air cleaners and to inform how to select them correctly to the users. The efficiencies of removing suspended bacteria per hour were $64.3{\pm}13.1%$ for filter, wet, and complex type, respectively, which showed the complex type was the most efficient. The removal efficiencies of formaldehyde (HCHO) after two hours operation of air cleaners showed 88.3% and 81.1% for filter and wet type, respectively. The efficiency of complex type, with removal rate of 55.5~58.4%, was decreased after 30 minutes operation. Therefore, it is recommended to perform over 60 minutes when doing air cleaner certification test for HCHO removal efficiency. Generally, air cleaners having low wind volume showed higher efficiency. All tested air cleaners had no potential for removing of volatile organic compounds (VOCs), which is toxic substances, and it is desirable to develop a device which can control these substances. The results also confirmed that there was no ozone production from all tested air cleaners. And it is recommended to ventilate for 20 minutes every four hours to maintain 50% ventilation status.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05a
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• pp.38-42
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• 2004

A pilot-scale experiment for the treatment of red tide in the enclosure was done in sea area of Shandong Province, P. R. China on Aug. 25, 2002. With the method of strong dielectric barrier discharge in microgap, $O_2$in air and $H_2O$ in seawater are ionized and dissociated into large numbers of OHㆍradicals, and then dissolved into a part of seawater to form OHㆍsolution of high concentration. With OH' concentration of 0.68mg/L, the kill efficiencies of 29 kinds of red tide organisms such as Chaetoceros lorenzianus and so on reached 99.89%, in which the kill efficiencies of bacterium and vibrio were 100%, and that of Gonyaulax cysts and Prei. Cysts were up to 100%. At the same time, the content of chlorophyll-a was decreased into the lowest limit of test. DO saturation of seawater was greatly increased to 100% because the residual OHㆍradical was decomposed into $H_2O$ and $O_2$after 20 minutes, Therefore the treatment of red tide using OHㆍradicals is a kind of advanced oxidation technology, which realizes zero pollution, zero emission and zero residual in the process of the production of OHㆍradicals and the treatment of red tide.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.181-185
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• 2005

We investigated the fermentative production of lactic acid from cheese whey and corn steep liquor as cheap raw materials using Lactobacillus sp. RKY2 to reduce the manufacturing cost of lactic acid. Lactic acid yields were obtained at more than 0.98 g/g from medium containing whey lactose. Lactic aid productivities and yields obtained from whey lactose were slightly higher than those obtained from pure lactose. The final concentration of lactic acid increased with increase, in whey lactose concentration, whereas the lactic acid productivity decreased probably due to substrate inhibition. The fermentation efficiencies were improved by addition of more corn steep liquor to the medium.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.101-105
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• 1987

A new probabilistic production costing simulation model has been developed based on the effective load and economic load dispatch. The best model must be able to simulate the real world exactly and the computing efficiencies are also reasonable. This proposed model is a new concept for the probabilistic production costing simulation model. This model is compared with the available existing ones through two sample systems, and the excellent results are shown.