• Environmental and Resource Economics Review
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• v.17 no.3
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• pp.31-59
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• 2008

This paper is intended to analyze the toxic substances transmission between South Korea and U.S. through international trade, based on 2000 international input-output data and both country's toxic substances. According to result, The high TEI sectors are metal, chemical and general machinery in Korea, and the high TEI sectors of America are electric & electronics, Chemicals, Rubber and Plastics. Korea's export structure to America is more pollutant than America's export structure to Korea.

• Environmental and Resource Economics Review
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• v.20 no.2
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• pp.291-308
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• 2011

The success of a target of 'low-carbon green growth' depends on whether installing energy-saving capital would result in an increase in industry's productivity growth. Defining total factor productivity from a dual cost function, this paper estimates the contribution of energy efficiency investment to productivity growth by analyzing the sources of growth of productivity index for the primary metal industries. Empirical results show that, on average, energy efficiency investment increased the annual rate of productivity growth by 1.16 percentage points over th period 1982~2006. In addition, The scale effect positively affected the contribution of energy efficiency investment on productivity growth.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.549-556
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• 2007

The study was carried out to examine on the refiner discharge from Alaska pollock as a collagen resource by characterizing biochemical and functional properties of collagen. The refiner discharge from Alaska pollock surimi manufacturing was a good resource for collagen extraction according to the results of total protein, heavy metal, volatile basic nitrogen, collagen content, amino acid composition, and thermal denaturation temperature (TDT). TDT of acid soluble collagen from refiner discharge showed $20.7^{\circ}C$, which was similar to that of collagen from Alaska pollock muscle and was higher than that of collagen from Alaska pollock skin. TDT of acid-soluble collagen from refiner discharge was, however, lower than those of skin collagens from warm fish and land animal. Acid-soluble collagen from refiner discharge of Alaska pollock could be used as a functional ingredient for food and industrial applications according to the results of water and oil absorption capacities, and emulsion properties. In addition, if the thermal stability of the acid-soluble collagens is improved, collagen from refiner discharge from Alaska pollock could be more effectively used.

• Applied Science and Convergence Technology
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• v.23 no.1
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• pp.14-26
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• 2014

Copper is an important component from coin metal to electronic wire, integrated circuit, and to lithium battery. Copper oxides, mainly including $Cu_2O$ and CuO, are important semiconductors for the wide applications in solar cell, catalysis, lithium-ion battery, and sensor. Due to their low cost, low toxicity, and easy synthesis, copper oxides have received much research interest in recent year. Herein, we review the crystallization of copper oxides by designing various chemical reaction routes, for example, the synthesis of $Cu_2O$ by reduction route, the oxidation of copper to $Cu_2O$ or CuO, the chemical transformation of $Cu_2O$ to CuO, the chemical precipitation of CuO. In the designed reaction system, ligands, pH, inorganic ions, temperature were used to control both chemical reactions and the crystallization processes, which finally determined the phases, morphologies and sizes of copper oxides. Furthermore, copper oxides with different structures as electrode materials for lithium-ion batteries were also reviewed. This review presents a simple route to study the reaction-crystallization-performance relationship of Cu-based materials, which can be extended to other inorganic oxides.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.2
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• pp.173-181
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• 2019

The paper aims to evaluate the combination of strategies that influence the success of New Technology Based Firms (NTBFs) located in isolated areas with resource constraints. We utilize the Kauffman Firm Survey to construct a subset of 224 firms operating in primary metal manufacturing industries and who are located in non-thriving areas. We focus on the impact of technological strategy, in the form of Inward Technology Licensing (ITL), combined with financial strategy, in the form of increased financial slack. Using a negative binomial-specification technique to model these relations, we find that ITL positively impacts internal innovation in the firm and this relation is strengthened by the presence of greater financial slack. This positive impact of financial slack supports the behavioral theory of the firm rather than agency theory in that financial slack enables further innovation rather than stifling it. This research confirms the importance of resource acquisition, suggesting that entrepreneurs may utilize external sources of knowledge in an effort to build a favorable situation when facing the challenges of location. Finally, by presenting evidence showing the compatibility of a financial strategy with a knowledge strategy (ITL), this study emphasizes the importance to entrepreneurs of choosing the proper combination of varying strategies.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.4
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• pp.291-297
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• 2019

Phosphorus is a vital resource for sustaining agriculture and nutrition, but a limited non-renewable resource. Thus, the recovery of phosphorus from waste activated sludge(WAS) was attempted by microwave heating and magnesium ammonium phosphorus(MAP) crystallization. Polyphosphate-accumulating organisms(PAOs) in WAS release phosphate from the cell when they are exposed to high temperature environments. Microwave heating caused phosphorus and ammonia to release from WAS. The amount was increased with increasing temperature, showing that 88.5% of polyphosphate present in the cells were released in the form of phosphate at $80^{\circ}C$. A similar result was also observed in the release of ammonia. On the other hand, both phosphorus and ammonia were crystallized with magnesium, and then was harvested as MAP. Phosphorus recovery rate reached almost 97.8%, but the ammonia was about 13.4%. These results cleary indicate that phosphorus could be recovered from WAS using a physiological trait of PAOs. Heavy metal analyses also show that the MAP crystal is useful and safe as a phosphorus fertilizer.

• Journal of Korea Society of Waste Management
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• v.35 no.7
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• pp.616-626
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• 2018

The quality standards of solid refuse fuel (SRF) define the values for 12 physico-chemical properties, including moisture, lower heating value, and metal compounds, according to Article 20 of the Enforcement Rules of the Act on Resource Saving and Recycling Promotion. These parameters are evaluated via various SRF Quality Test Methods, but problems related to the heavy metal content have been observed in the microwave acid digestion method. Therefore, these methods and their applicability need improvement. In this study, the appropriate testing conditions were derived by varying the parameters of microwave acid digestion, such as microwave power and pre-treatment time. The pre-treatment of SRF as a function of the microwave power revealed an incomplete decomposition of the sample at 600 W, and the heavy metal content analysis was difficult to perform under 9 mL of nitric acid and 3 mL of hydrochloric acid. The experiments with the reference materials under nitric acid at 600 W lasted 30 minutes, and 1,000 W for 20 or 30 minutes were considered optimal conditions. The results confirmed that a mixture of SRF and an acid would take about 20 minutes to reach $180^{\circ}C$, requiring at least 30 minutes of pre-treatment. The accuracy was within 30% of the standard deviation, with a precision of 70 ~ 130% of the heavy metal recovery rate. By applying these conditions to SRF, the results for each condition were not significantly different and the heavy metal standards for As, Pb, Cd, and Cr were satisfied.

• Resources Recycling
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• v.29 no.2
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• pp.69-77
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• 2020

With rapid increasing production and installation, recycling of photovoltaic modules has become the main issue. According to the research, the accumulation of waste modules will reach to 8600 tons in 2030. Moreover, Crystalline-silicon (c-Si) Photovoltaic modules account for more than 90% of the waste. C-Si PV modules contain 1.3% of weight of photovoltaic ribbon inside which contains the most of lead, tin and copper in the PV modules, which would cause environmental and humility problem. This study provided a valuable metal separation process for PV ribbons. Ribbons content 82.1% of Cu, 8.9% of Sn, 5.2% of Pb, and 3.1% of Ag. All of them were leached by 3M of hydrochloric acid in the optimal condition. Ag was halogenated to AgCl and precipitated. Cu ion was extracted and separated from Pb and Sn by Lix984N then stripped by 3M H2SO4. The effect of the optimal parameters of extraction was also studied in this essay. The maximum extraction efficiency of Cu ion was 99.64%. The separation condition of Pb and Sn were obtained by adjusting the pH value to 4 thought ammonia to precipitate and separate Pb and Sn. The recovery of Pb and Sn can reach 99%.

• Design & Manufacturing
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• v.13 no.4
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• pp.17-22
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• 2019

Currently, studies on weight reduction and fuel efficiency increase are the most important topics in the automotive industry and many studies are under way. Among them, weight reduction is the best way to raise fuel efficiency and solve environmental pollution and resource depletion. Materials such as aluminum, magnesium and carbon curing materials can be found in lightweight materials. Among these, research on improvement of bonding technology and manufacturing method of materials and improvement of material properties through study of ultrahigh strength steel sheet is expected to be the biggest part of material weight reduction. As the strength of the ultra hight strength steel sheet increases during forming, it is difficult to obtain the dimensional accuracy as the elastic restoring force increases compared to the hardness or high strength steel sheet. It is known that the spring back phenomenon is affected by various factors depending on the raw material and processing process. We have conducted analytical evaluations and studies to analyze the springback that occurs according to the cross-sectional shape of the ultra high tensile steel sheet.

• Journal of the Korea Furniture Society
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• v.27 no.2
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• pp.80-90
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• 2016

The idea of Sustainable, first mentioned in "Our Future (Bruntdland)" from the United Nations report released in 1987 has been highly affect design disciplines in developed countries in 21st century. It relocated industrial society and structure's attentions to nature and recourse conservation and reuse. Designed and manufactured products eventually disposed and it leads to waste of resources as well as creates environmental issues. Unfortunately, vast majority of designers starts designing without anticipation of this matter and produce more believing this leads to more sales. However shorter life of a product will create bigger increase of resource consumption and waste than, importance of re-usage and recycle will eventually increase. In modern furniture industry metal and plastics are frequently used beside wood that material has been diverse than in past. However, there are lack of plans and regulations of re-usage of those material due to difficulties of separating each different materials and collecting due to it's size. This study would like to look into recycling rate, methods and usage of three major materials (wood, metal, plastic) that is typically used in current furniture industries. Furthermore, see the potential of sustainable furniture by analyzing furniture practices made by each different recycled material from old furniture and what designers should consider to achieve feasibility of sustainable furniture.