• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.254-260
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• 2015

This paper assesses the tariff reduction on imported wood products that will have impact on the demand for domestic wood products in South Korea, by estimating the Armington substitution elasticities based on the assumption that they are imperfect substitutes. Results indicate that domestic and foreign wood products are far from perfect substitutes to each other. The substitution elasticities in plywood and fiberboard appeared to be high, implying that tariff reduction may have negative effects on those industries. On the contrary, imported and domestic particleboard showed a low substitution elasticity. The decline of fiberboard industry may lead to the decline in forestry since fiberboard is produced mainly by thinned woods supplied from domestic forests. Therefore, effective countermeasures to enhance the competitiveness of wood products industry are needed to cope with the market opening.

• Resources Recycling
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• v.29 no.5
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• pp.64-72
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• 2020

When the multi-stage combustion process is applied to the cement kiln to reduce nitrogen oxide emissions in the cement industry, oxidation/reduction section that can increase combustion efficiency by reducing NO_x to NO and completely burning unburned materials is essential In this study, when applied the oxidation/reduction system of the cement kiln preheater and calciner, the optimal oxidation/reduction calcination crisis that can secure the quality stability of the final product, cement clinker, was to be observed macroscopically, and the mass change of raw materials according to the burning conditions, decarbonation rate, and calcination rate were investigated. The results showed that the thermal decomposition of raw materials tends to be promoted in the oxidation condition rather than in the reduction condition, and that the thermal decomposition of limestone, which has a relatively high CaO content, is carried out later than that of cement raw meal, which is thought to be caused by the CO₂ fractionation in the kiln. The thermal decomposition properties of raw materials according to oxidation/reducing burning condition showed a relatively large difference in temperature range lower than normal limestone themal decomposition temperature, which is thought to be expected to improve the thermal efficiency of raw materials according to the formation of oxidation condition in the section 750℃ of burning temperature. However, for this study, lab scale. Because there is a difference from the field process as a scale study, it is deemed necessary to verify the actual test results of the pilot scale.

• Clean Technology
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• v.14 no.2
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• pp.144-151
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• 2008

Life cycle assessment was carried out to evaluate the environmental values of dimethylas a diesel alternative fuel with the assumption of dimethyl ether production from natural gas via synthesis gas. The whole life cycles from raw material acquisitions to the final usages of diesel and dimethyl ether were involved in the assessment. Inventory analysis showed that the most significant environmental impacts came from resource depletions and air emissions. Impact assessment revealed that dimethyl ether was environmentally better in the aspect of human health and ecosystem quality but worse in resource depletions compared with diesel fuel. Suggestions for environmental improvement of dimethyl ether as a diesel alternative fuel were prepared based on the assessment results.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.4
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• pp.627-639
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• 1996

Charateristics of Ansan and Boryong coal fly ashes collected at different seasons were investigated for the recycling them as ceramic raw materials. The effect of pH treatment on the classification of Ansan coal fly ashes by elutriation was discussed. Charateristics of ansan and boryong coal fly ashes were not significantly changed with power plants and seasons. major crystalline phases were mullite and quartz. These results suggested that coal fly ashes cab be used as raw materials instead of clay minerals. However, particle size distribution was very broad from a few $\mu\textrm{m}$ to over $100\;\mu\textrm{m}$. Especially, ansan coal fly ashes have various morphologies. Therefore, coal fly ashes should be classified before using as raw materials. Because of higher dispersion by pH treatment, spherical cenospheres were mainly collected in the 4th step and particle size distribusion was also decreased by elutriation for the ansan coal fly ashes. The specific surface area of the sample collected in the 4th step was $1.24\;m^{2}/g$ which was smaller than that of not treated Ansan coal fly ashes.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.403-410
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• 2021

This paper aimed to increase the functionality and competitiveness of rice bran, which is used as an alternative food and cosmetic raw material, through fermentation. As a result of comparing the enzyme activity of 𝛼-amylase, CMCase, 𝛽-glucosidase, protease, etc. of fermented rice bran using standard strains with 6 strains with excellent enzyme activity among 50 strains of Saccharomycopsis fibuligera isolated from 5 types of Nuruk, A8 strain showed excellent enzyme activity of 13.7%, 21.1%, 50.3%, and 10.0% compared to the KCTC 7806 strain. As a result of the ABTS and DPPH tests as a result of fermentation, it was confirmed that rice bran fermented with A8 had 1.12 times and 1.28 times more antioxidant activity than rice bran fermented with KCTC 7806 strain. In this paper, it was possible to confirm the S. fibuligera A8 strain superior to the standard S. fibuligera strain KCTC 7806.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.340-360
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• 2010

The depletion of fossil fuels, ecological problems associated with $CO_2$ emissions climate change, growing world population, and future energy supplies are forcing the development of alternative resources for energy (heat and electricity), transport fuels and chemicals: the replacement of fossil resources with $CO_2$ neutral biomass. Several options exist to cover energy supplies of the future, including solar, wind, and water power; however, chemical carbon source can get from biomass only. When used in combination with environmental friend production and processing technology, the use of biomass can be seen as a sustainable alternative to conventional chemical feedstocks. The biorefinery concept is analogous to today's petroleum refinery, which produce multiple fuels and chemical products from petroleum. A biorefinery is a facility that integrates biomass conversion processes and equipment to produce fuels, power, and value-added chemicals from biomass. Biorefinery is the co-production of a spectrum of bio-based products (food, feed, materials, and chemicals) and energy (fuels, power, and heat) from biomass [definition IEA Bioenergy Task 42]. By producing multiple products, a biorefinery takes advantage of the various components in biomass and their intermediates therefore maximizing the value derived from the biomass feedstocks. A biorefinery could, for example, produce one or several low-volume, but high-value, chemical or nutraceutical products and a low-value, but high-volume liquid transportation fuel such as biodiesel or bioethanol. Future biorefinery may play a major role in producing chemicals and materials as a bridge between agriculture and chemistry that are traditionally produced from petroleum. Industrial biotechnology is expected to significantly complement or replace the current petroleum-based industry and to play an important role.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.11a
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• pp.14-14
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• 2001

현재 제지용 펄프 및 펼프 원료의 국내 자급상태는 매우 낮은 수준이다. 따라서 원료 가격변동과 환율에 따라 수익성은 물론, 원료 수급에도 큰 영향을 받게 된다. 최근 버 진펄프의 가격상승은 재생펄프 사용량과 고지수입량을 더욱 늘리고 있으며, 이들의 사 용에 따른 품질저하 개선노력도 꾸준히 행해지고 있다. 그러나 원가절감과 품질유지라 는 두 마리 토끼를 한꺼번에 잡는 것은 그리 쉬운 일이 아니며 그 효과 또한 점점 미 미해 지고 있는 실정이다. 외국의 경우 이러한 문제점들을 펄프소재면에서 접근하여 해 결하고자 하는 시도가 있었다. 중국은 벗짚펄프를 제지용으로 적용하여 오랜 시행착오 끝에 성공을 거두고 있으며, 남미에서도 수수 등을 이용한 제지용 펼프 개발에 노력과 투자를 아끼지 않고 있다. 이는 제한된 원료의 사용만으로 직면하고 있는 여러 문제점 들을 해결하기가 힘들다는 언식에서 출발한 것이며, 새로운 원료개발 자체가 그 해결방 안으로서 충분한 가치가 있음을 보여준다고 하겠다. 이와 같은 맥락에 따라 국내에서 적용이 가능한 소재를 조사하였으며 우선적으로 신서란을 선택하게 되었다. 신서란은 뉴질랜드가 원산지로 알려져 있으며 오래전부터 제주도에 자생하고 있는 다년생 초본류이다. 수많은 경질섬유(hard fiber)중에서도 경제적으로 재배되는 유일한 작물로 선박용 로프, 그물, 범포 등의 원료로 사용되었으나 현재는 화학섬유로 대체되 어 그 사용이 전무한 실정이다. 선서란은 고강도와 우수한 유연성, 탄력성 및 양호한 광학적 성질을 가지고 있으며 무엇보다 척박한 땅에서도 생장이 왕성하여 재배가 쉽다 는 것이 가장 큰 장점이다. 본 연구는 펄프용 섬유로서 양호한 기본특성을 가진 신서란 을 이용한 펄프를 기존 제지공정에 일정량 투입함으로써 얻고자 하는 종이의 일반물성 개선 및 특수기능 향상에 도움이 되는 제지용 펄프로서의 가능성을 알아보고자 하였다.이어서 몇십%의 현을 억제하지는 못한다는 결론을 도출할 수 있었다. 연구의 결과를 요약하면 다음과 같다. 첫째, 한국과 미국 패션제품의 지난 십년간의 가격 과 품질의 상관관계는 매우 약한 정(+)의 상관을 가지고 있었다. 한국패션제품의 전체 서열상관계수의 평균은 0.091이었고, 미국의 상관계수 평균은 0.192였 다. 상관계수의 수치만으로 볼 때 한국보다는 미국 패션제품의 가격과 품질간의 상관관계가 조금 높게 나타났으나, 양국간 통계적인 차이는 없었다. 또한, 한국 패션제품의 경우에는 제품군의 가격대별 상관관계를 살펴보았는데, 그 결과 1만원 미만의 저가 제품군과 330만원이상의 고가의 제품군의 경우 부(-)의 상관계수를 나타냈다. 둘째. 1990년대 한국과 미국 패션시장의 가격과 품질간의 상관계수의 범위는 제품군별. 산업범주별 로 상이한 분포를 보이고 있었다. 패션제품군별로 보 면, 한국의 경우는 가장 높은 '여행용가방(r = 0.707)' 에서 가장 낮은 '자외선 차단화장품(r = -0.58)'까지, 그리고 미국 패션제품군의 상관계수의 범위는 '팬티 스타킹'의 0.820에서 '남성용 런닝슈즈'의 -0.472까지의 분포를 나타냈다. 마지막으로, 제품의 가격과 품질에 대한 정보를 소비자가 알 경우 얻을 수 있는 소비자의 구매이득 을 추산한 결과 패션제품시장에서 완전한 품질정보를 가지고 있다고 가정한 '현명한 사람'은, 최고가격의 제품만을 구입한다고 가정한 '부유한 사람들'의 구입방식에 비해 최고 좋은 품질의 상품을 총 지불액의 비율로 보아, 한국의 소비자는 약 50% 정도를, 미국의 소비자는 약 91%나 되는 액수를 절약하여 구매할 수 있는 것으로 나타났다. 이상의 본 연구의 결과를 종합하여 볼 때 한국과 미국 모두 제품군별, 그리고 산업범주별로 상관관계가 차이를 보이고 있어, 양국의 소비자들이 패션제품 의 품질을 평가함에 있어 오로지 가격에 대한

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.25-32
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• 1973

Noodles and cookies were made from composite flours based on domestic resources and their quality was assessed to obtain the following results. 1) Various flours containing $10{\sim}20%$ defatted soy flour did not form belt in noodle-making process, but the use of 1.5% GMS + 2% Methocel as binder was very effective in noodle-belt formation and cooking quality. 2) Out of four raw flours, naked barley flour was most suitable for noodle-making. Addition of wheat flour at 25% or 50% level into the four composite flours greatly improved the quality of noodles and particularly that based on naked barley was similar to wheat flour in color and gave rather palatable taste. 3) Though cookie could be made from any composite flours without using GMS or CSL, naked barley flour was the best in sensory evaluation of the product. 4) Addition of wheat flour at 25% or 50% level into above composite flours gave cookies comparable to standard wheat product except the case of composite flour based on defatted rice bran.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.3
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• pp.50-59
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• 2010

A pilot-scale test for production of biogas was conducted in an specially designed anaerobic digester (KH-ABC) in which the highly concentrated organic waste (food-waste and piggery-manure) was treated. The effect of inhibitive material to the reaction on anaerobic digestion and the feasibility of digested fluid for the liquefied fertilizer were investigated. The production rate of biogas, the concentration of methane($CH_4$) in biogas, and the digesting rate of volatile solid(VS) were analyzed in the variance of the operating conditions ; the influent rate, the mixture ratio of food waste and piggery manure, and the hydraulic retention time(HRT), etc. The production rate of biogas increased from 1.2 to $2.0kg-VS/m^3{\cdot}d$ with the organic loading rate(OLR). The most suitable operating conditions were recorded at $6m^3/day$ of an influent rate, 2:3 of the raw material mixture ratio(food waste : piggery manure) and 25 days of HRT, respectively. Under those conditions, the production rate of biogas, the concentration of methane($CH_4$) in biogas and the digesting rate of volatile solid(VS) were $220m^3/day$, 64%, and 70%, respectively. The concentration of inhibitive materials was below toxic standard and the anaerobic digested fluid(raw material mixture ratio of 3:7) could meet the condition of the liquefied fertilizer.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.101-101
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• 2011

재생 셀룰로스 섬유의 원료로 사용되는 셀룰로스는 면, 마, 목재 등 고등식물의 주성분으로 매년 수십억톤이 광합성에 의하여 생산되어지고 있다. 따라서 석유류와 같은 화석연료의 가격 변동에 영향을 받지 않고 안정적으로 수입되고 있다. 또한, 셀룰로스에는 면이나 마류 등과 같이 간단한 정제 처리에 의해 의류용 섬유로서 사용될 수 있는 것과 목재 섬유와 같이 펄프화하여 종이, 인견섬유, 필름 등으로 사용되어지는 것이 있으며, 셀룰로스 유도체도 제조할 수 있다. 현재까지 개발된 섬유들 중 대표적인 셀룰로스계 재생섬유인 비스코스 레이온(Viscose rayon)은 그 제조 방법이 환경적으로 치명적인 문제를 안고 있으나 고유의 우수한 드레이프성, 흡습성, 독특한 광택, 시원한 촉감 등을 가지고 있어 그 소비는 꾸준한 상황이다. 이러한 Viscose rayon을 대체하기 위하여 친환경적인 공법을 이용하여 개발된 Lyocell 제품이 각광을 받고 있다. 면 셀룰로스 재생섬유는 기존의 Lyocell섬유에 비해 신도는 높고 모듈러스가 낮아 Modal과 같은 촉감을 가지고, 피브릴 발생이 없어 방사공정에서 가교반응이 필요치 않는 것으로 기대된다. 친환경 공법인 Lyocell 공법으로 개발된 면 린터 원료를 이용하여 면 린터 셀룰로스 재생섬유 제조기술을 개발하고자 한다. 따라서 본 연구에서는 면 린터 셀룰로스 재생섬유의 기술적인 신뢰성을 검증하기 위해 면 린터 셀룰로스 재생섬유소재 피브릴화 정도의 표준화 시험법을 연구하고자 한다. 사용원단으로 Tencel A-100, Tencel standard, Modal, Lyocell LF, 면 린터 섬유를 사용하였으며, 세탁, 염색, 알칼리조건 처리에 따른 물성 변화를 알아보았다. 물성 변화는 전자현미경으로 측정하였다.