• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.50-50
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• 2004

• Journal of Powder Materials
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• v.19 no.1
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• pp.79-86
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• 2012

• 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.

• Clean Technology
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• v.1 no.1
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• pp.34-46
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• 1995

Clean Technology goes beyond Clean-UP (or "End of PiPe) Technologies to include Pollution prevention, waste minimisation, and cleaner production. However, the concept of Clean Technology goes deeper than changes in technology, to ways in which human needs can be satisfied sustainably. In other words, Clean Technology, concentrates on delivering a human benefit rather than making a product. Introducing cleaner technology may therefore involve new commercial relationships as well as new technological practices. In some economic sectors, this involves leasing or providing a service rather than selling a product. Life Cycle Assessment (LCA) is an important tool in Clean Technology. LCA involves determining all the resources used and all the wastes and emissions produced in providing the human benefit. Use of LCA ensures that improved environmental performance in one part of the Life Cycle is not achieved merely at the expense of more environmental damage elsewhere. Going beyond LCA, the concepts of Life Cycle Design and "metabolised" use of materials are approaches to obtain maximum benefit from materials as they pass through the human economy. "Closed-loop" use can be a component of clean technology. Looking beyond simple re-use and recycling, a material may pass through a "cascade of uses". typically a series of applications with progressively lower performance specifications. Closed-loop use necessarily involves a change in commercial practice, because the material or product must be recovered after use.

• Journal of Distribution Science
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• v.20 no.7
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• pp.47-56
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• 2022

Purpose: As the need to transition into the distribution of cleaner energy has garnered corporate and scholarly interests, this study aims to track the research trends in sustainable energy supply chains for five years before 2021. Research methodology: This study was conducted by a bibliometric literature review and analysis to map the field's evolution between 2016 and 2020. Out of an initial title search result of 2,484 papers from the Scopus engine, filtering led to 180 documents obtained. The data was exported in excel format (CSV) to VOSviewer software to generate and analyze network visualization of sustainable energy supply chain trends. Results: The results revealed China's the highest publishing country, with 36 research papers. The Journal of Cleaner Production was the top publishing source, with 22 papers per year. These findings showed five clusters formed in the bibliographic coupling of countries. Circular Economy and Green Supply Chain Management represent the current hot topics. Research gaps identified in the field included limited cross-industry testing and modifying sustainable supply chain models. Conclusion: This paper contributes to the sustainability literature on supply chains by providing an overview of trends and research directions for scholars' and practitioners' consideration in future research.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.3
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• pp.169-180
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• 2002

Rayleigh scattering and laser induced predissociative fluorescence are used to obtain two-dimensional images of temperature and species concentration in a laminar non-premixed flame of a diluted hydrogen jet. Rayleigh scattering cross-sections are experimentally obtained at 248nm. Planar images of OH and $O_2$ with tunable KrF excimer laser which has a) $0.5cm^{-1}$ linewidth, b) 0.5nm tuning range, c) 150mJ pulse energy, and d) 20ns pulse width are obtained to determine spatial distributions of OH and $O_2$. The technique is based on planar laser induced predissociative fluorescence (PLIPF) in which collisional quenching is almost avoided because of the fast predissociation. Dispersed LIPF spectra of OH and $O_2$ are also measured in a flame in order to confirm the excitation of single vibronic state of OH and $O_2$. OH and $O_2$ are excited on the $P_2$(8) and $Q_1$(11) line of the $A^2{\Sigma}^{+}({\nu}^{'}=3)-X^{2}{\Pi}({\nu}^{''}=o)$ band and R(17) line of the Schumann-Runge band $B^{3}{\Sigma}_{u}{^-}(\nu^{'}=0)-X^{3}{\Sigma}_{g}{^-}({\nu}^{''}=6)$, respectively. Fluorescence spectra of OH and Hot $O_2$ are captured and two-dimensional images of the hydrogen flame field are successfully visualized.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.651-659
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• 2000

The characteristics of ammonia removal by natural neutralizer were studied by using a scrubber type equipment. As operation parameters, neutralizer dilution ratio, neutralizer inlet flowrate, air flowrate and initial ammonia concentration were selected and their effects on ammonia removal efficiency were investigated. The optimal removal effect was achieved at neutralizer dilution ratio of 1.0% and neutralizer inlet flowrate of $60m{\ell}/min$. On the other hand, with respect to air flowrate and initial ammonia concentration, there was no significant effect on removal efficiency, when loading rate was considered. In addition, ammonia removal reaction was investigated by analyzing the ammonia oxides, such as nitrites and nitrates, after reacting ammonium solution with natural neutralizer. The result shows a partial oxidation by natural neutralizer besides dominant absorption of ammonia.

• 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.

• Clean Technology
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• v.22 no.1
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• pp.62-72
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• 2016

These days, it seems to be a core time to build proactive prevention systems for small and medium sized enterprises due to the reinforced safety in the production process and the strong environmental regulations (ES) both at home and abroad. On the other hand, a network of experts that combines the industrial environment and production safety as well as even the knowledge services companies are not quite enough to prepare to support them. In this study, through a survey of experts the current statue of the convergence of industrial environment and production safety were reviewed, and the structure of knowledge ES cluster was proposed to overcome this current state. Detailed strategies such as the development and distribution of ES convergence methodology, ES efficiency analysis and an ES roundtable.

• Journal of Animal Environmental Science
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• v.12 no.3
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• pp.133-140
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• 2006

The climate of stall significantly influences on animal production ability. High concentration of ammonia gas, $CO_2$ and lots of dust are found in modern densely raising stall system, as results, they provide a negative influence on animal and farmer health, and production ability. Therefore, it is necessary to keep clean the inside air of stall to increase the productivity. An air cleaner of wet type, consisting of a fan, a motor, rotating discs, a dust collector, a water bowl, an ozone generator etc, has been developed to clean the stall air. The work principle is that the inside air is sucked through the fan, and the rotating discs make water into fineness spray and blow into the stall. The rest water flows down to the dust collector. In the present study, we measured the dust, ammonia gas, odor, temperature and humidity in a swine stall that were installed two wet air cleaners with 700 fattening swine with On-mode and Off-mode of wet air cleaners. The dust measure was divided into 3 categories, TSP, $PM_{10}$, and $PM_{2.5}$. In summer, the TSP in on-mode were maximum $0.259mg/m^3$ and minimum $0.128mg/m^3$, and the average was $0.195mg/m^3$. These are comparable to the data from Off-mode stall that maximum $0.308mg/m^3$, minimum $0.139mg/m^3$, and average $0.277mg/m^3$. However, $PM_{10}$ and $PM_{2.5}$ showed any significant differences between the tests. The concentrations of ammonia gas in Off-mode stall were maximum 13.8 ppm and minimum 5.9 ppm, and the average was 8.47 ppm. However in On-mode stall the ammonia gas concentrations were maximum 10.5 ppm and minimum 5.5 ppm, and the average was 7.63 ppm. The concentration of ammonia gas in On-mode was 10% in average lower than off-mode stall. Odor was measured by olfactometer. In the Off-mode stall, the odor unit were maximum 420 $Ou/m^3$ and minimum $300\;OU/m^3$, and the average was $367\;OU/m^3$, but in the On-mode stall the odor unit were maximum $330\;OU/m^3$ and minimum $210\;OU/m^3$, and the average was $253\;OU/m^3$. Odor removal efficiency was about 31% in On-mode stall.