• 한국가구학회지
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• 제11권2호
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• pp.45-53
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• 2000

This study was carried out to determine the suitability of 3 months old bamboo species of Phyllostachys bambusoides S. et Z., Phyllostachys Pubescens Mazel and Phyllostachys nigra var henonis Stapf as raw materials for the manufacture of strandboard. Total of 108 strandboards were made using urea-formaldehyde resin content level of 12% and one percent of liquid wax emulsion. The strandboard consisted of three layers the top and the bottom layer of which were oriented to the same direction and weighted 25% of the strandboard each. The middle core layer weighed 50% of the board and was perpendicular to the outer top and bottom layers. Analysis was performed to determine the effect of strand lengths and Uowing years of 3 months, 2 years and 3 years on strandboard properties. The physical and mechanical properties of bamboo species and boards were measured and compared to the standard requirements of strandboards. The results are as follows; 1. The more the growing years the higher the density of bamboo. Top part of bamboo indicated higher density value than that of bottom part. 2. Bamboo showed higher static bending strength compared to the main wood species. Longer growing years of bamboo generally inclosed the static tending strength out there were no statistical significancies for Phyllostachys bmbusoides S. et Z. and Phyllostachys pubescens Mazel. 3. Strand length indicated no difference on density and moisture content of strandboard. 5 cm of strand length gave the best static bending strength and internal bonding strength. Bamboo strandboard exhibited lesser extents of thickness swelling than that of CSA standard. 4. 3 months old bamboo gave higher static bending strength of strandboard than those of 2 years and 3 years old bamboo. In case of Phyllostachys nigra var henonis Stapf, 3 months old bamboo indicated higher internal bonding strength than those of 2 years and 3years old bamboo. but in Phyllostachys bambusoides S. et Z., Phyllostachys pubescens Mazel, there were no difference among growing years. Growing years showed no different physical properties of bamboo strandboard.

• Architectural research
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• 제15권1호
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• pp.25-33
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• 2013

The amount of construction waste increased to 176,447 ton/day in 2008 from 28,400 ton/day in 2000, a 6-fold increase in just 10 years. Such dramatic increase in the waste of concrete, asphalt concrete, wood and metals was due to demolition of old buildings as well as a great number of building redevelopment projects and hurried city industrialization. Many buildings targeted for demolition today were built in line with the government policy to provide affordable housing to citizens in the shortest time possible and consequently, said buildings underwent rapid deterioration and required periodic repairs and reconstruction. Based on the above, we predict that construction waste will continue to increase for the foreseeable future. In particular, due to limited availability of suitable space to construct apartments and residential buildings in the city, old buildings are being torn down to make space for new development, further increasing construction waste. In light of that, efforts to recycle as well as reduce generated waste are urgently required.

• 펄프종이기술
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• 제46권6호
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• pp.34-40
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• 2014

Wood fibers for medium density fiberboard (MDF) was used in the filler layer of the white duplex board for increasing thickness and bulk of the board. The MDF fibers and the old corrugated container (OCC) furnish were refined, and mixed together to form paperboard. At optimum mixing ratios and refining degrees, stiffness and tensile strength of the MDF fiber-containing board were higher than those of the board with 100% OCC. It was found that there was possibility to reduced basis weight of the filler layer down to 90% of the all OCC furnish by judicious selection of the mixing ratio and the refining method of the MDF fibers. Drainage rate increase and potential drying energy savings were additional benefits.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2001년도 제18차 정기총회 및 학술발표 PROCEEDINGS
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• pp.61-63
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• 2001

Two experiments were conducted to investigate the feeding influence of wood vinegar and mixed with probiotics on performance and physiological related of broiler chicks for five weeks. Diets contained 21.5%, 3,100kcal/kg and 19.0% CP, 3,100kcal/kg ME for starting and finishing period, respectively. In Expt 1, Four levels of wood vinegar(0, 0.05, 0.10, 0.20%) were fed into two hundred forty chicks with four replicates. In Expt 2, 0, 0.1% wood vinegar(W), 0, 0.1% lactobacillus casei(L) and bacillus subtilis (B) were applied to 2${\times}$2${\times}$2 facotrial design for eight treatments with four replicates. Weight gain, feed intake, feed cholesterol were detected at five weeks old in each experiment. In Expt 1, Weight gain of chicks fed 0.1% wood vinegar(WV) was increased upto 1645.8g, but was not significantly different. However, chicks fed 0.2% WV showed the highest gain and siginificantly different compared to that of control (P＜0.05) for finishing period. Feed intake also showed similar tendency with weight gain. There were no statistical difference in feed conversion. Abdominal fat seemed to be decreased in WV supplemental groups, whereas ND antibody titer tended to increase in those treatments. In Expt 2, 0, 0.1% WV, lactobacillus, bacillus were combined with each other(W$\sub$0/L$\sub$0/B$\sub$0/, W$\sub$0/L$\sub$1/B$\sub$0/, W$\sub$0/L$\sub$0/B$\sub$1/, W$\sub$0/L$\sub$1/B$\sub$1/, W$\sub$1/L$\sub$0/B$\sub$0/, W$\sub$1/L$\sub$1/B$\sub$0/, W$\sub$1/L$\sub$1/ B$\sub$0/, W$\sub$1/L$\sub$0/B$\sub$1/, W$\sub$1/L$\sub$1/B$\sub$1). WV supplemental groups significantly improved feed conversion of all treatments(P＜0.05). There were no interaction in weight gain and feed intake. Total cholesterol was signficantly decreased in WV plus lactobacillus and ladtobacillus plus bacillus treatments. Liver to body ratio(%) of lactobacillus plus WV significantly decreased compared to that of other treatments. The results of these experiments showed that wood vinegar tended to improve the performance of broiler chicks, but was not effect in its combination with lactobacillus or bacillus treatments.

• 한국가금학회지
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• 제33권4호
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• pp.283-293
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• 2006

본 연구의 목적은 목초액 함유 활성탄(activated charcoal mixed with wood vinegar, AC)의 급여가 육계의 생산성 및 산란계에서 혈중 및 계란내 항생제 수준에 미치는 영향을 규명하기 위하여 본 연구를 실시하였다. 실험 1은 450수의 1일령 육용종 Ross 수평아리를 공시하여 처리당 3반복 반복당 25수씩 완전임의 배치하고, 항생제 0%(T1), 항생제 0.1%(T2), AC 1%(T3), AC 1% + 항생제 0.1%(T4), AC 2% (T5), AC 2% + 항생제 0.1%(T6)를 함유하는 실험 사료를 각각 5주간 급여하였다. 사료 섭취량과 증체량은 주 단위로 조사하여 성장 성적에 미치는 영향을 평가하였다. 실험 5주차 종료시에 각 처리구별로 10수씩 선발하여 도살하였고, 간, 복강지방, 가슴육, 기타 기관의 상대적 중량을 측정함으로서 도체 특성을 조사하였다. 가식성 근육의 물리적 특성은 가열 감량, 전단력가, 보수력, 육색을 측정하였고, 육질의 관능적 특성은 연도, 맛, 풍미, 다즙성 등을 측정하였다. 장 내 균 총 변화에 미치는 영향에서 총 균수, 대장균 및 유산균수를 조사하였다. 실험 2는 40주령의 Hy-Line Brown 산란계 90수를 공시하여 항생제 0.5%에 AC 0%(C), AC 1.0%(T1), AC 2.0%(T2)를 함유하는 실험 사료를 각각 2주간 급여하였다. 종료 후 혈액 채취 및 계란을 수거하여 혈액 및 계란 내 항생제 잔류 수준을 측정하였다. 실험 1에서 사료 섭취량, 증체량 및 사료 요구율은 처리구간에 통계적으로 유의한 차이는 없었다. 대사 에너지, 조 단백질 및 기타 필수 영양소 수준을 고려하면 AC의 급여가 성장에 부정적인 영향은 없는 것으로 판단되었다. 간, 복강 지방, 가슴육, 기타 기관의 상대적 중량에서는 처리간에 통계적으로 유의한 차이는 인정되지 않았다. 보수력과 가열감량 항목에서는 처리간에 큰 차이가 없었으나, 전단력가는 대조구에 비해 AC 첨가구에서 유의하게 높아지는(P<0.05) 경향을 나타내었다. 대조구에 비해 실험구에서 적색도는 낮아지는 경향을, 황색도는 증가하는 경향을 나타내었다. 풍미, 연도, 다즙성 및 총체적 선호도 항목 모두 처리간에 유의한 차이는 인정되지 않았다. 장 내 총균수, coli form 및 lactic acid bacteria 수는 항생제를 첨가한 (+) 대조구와 AC를 첨가한 처리구가 항생제를 첨가하지 않은 (-) 대조구에 비해 유의하게 낮은 수준이거나(P<0.05), 낮은 경향을 보였다. 실험 2에서는 AC 급여에 의해 혈청 및 계란 내 항생제 잔류량이 유의하게 감소하는 결과가 관찰되었다(P<0.05). 특히 AC급여 수준이 증가함에 따라 계란 내 항생제 잔류량은 유의하게 감소하였다. 본 연구에서는 육계 사료 내 AC의 첨가 급여가 생산된 계육의 외관적 특성을 개선시키는 효과가 시사되었고, 장내 총균수, 대장균 및 유산균수를 감소시키는 시키는 결과를 보였다. 산란계 사료 내 AC의 첨가 급여가 혈청 및 계란 내 항생제 잔류를 감소시키는 결과를 나타내었다.

• 한국농촌건축학회논문집
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• 제24권4호
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• pp.59-66
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• 2022

This study is to investigate the old buildings that have been built more than 50 years ago, targeting the areas of Seongan and Jungang-dong, the historic urban area of Cheongju. Their types and distribution characteristics are as follows. 1) First, the old buildings existing in downtown Cheongju account for 21.4% of 1,070 out of the total 5,000 buildings. Among them, wooden buildings before the 1950s accounted for 60% of them, resulting in severe aging. 2) Second, by use, 728 detached houses and 276 neighborhood living facilities account for 93.8% of the total, with 16 offices and 12 religious facilities. By structure, there are wood 65%, masonry 30%, and reinforced concrete 5% (54 buildings). By number of floors, the first floor 90%, the second floor 7.3%, and the third floor or higher 2.7% (30 buildings). The roof material is 51.6% of earthenware, followed by slate, cement, and slab. 3) Third, the old buildings are scattered all over the streets, and are concentrated in Namju-dong, Nammun-ro 1-ga-dong, Seoun-dong, and Sudong at the foot of Uamsan Mountain, a former refugee village. Also old buildings are distributed in Seoun-dong and Seokgyo-dong where hanok(korean traditional houses) are concentrated, in Namju and Nammunro 1 ga-dong blocks connected by alleys, and in cul-de-sac all over the place.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 춘계학술발표논문집
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• pp.167-173
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• 2006

Deinking is a series of unit operations designed to detach ink from cellulose fibers and separate the dispersed ink from the pulp slurry. Deinking chemicals are process aids that enable expensive mill equipment used in these unit operations to operate more efficiently - often much more efficiently. We propose the blended deinking agent with cellulolutic enzymes and synthetic collector in deinking pulp of conventional alkaline method. The deinking efficiency of old news print in alkaline pH was enhanced with enzyme treatments. The brightness of deinked pulp was increased with less residual ink particles and yield of enzymatic deinked pulp was improved compared to the deinked pulp of conventional alkaline method. Enzymes in biomass were use to Chemical Deinking for reduce environment pollution through surfactant and improve surfactants. examining into compatibility Enzymes and surfactants, these new materials are studied efficiency of deinking efficiency.

• 한국가구학회지
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• 제27권2호
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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.

• Journal of the Korean Wood Science and Technology
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• 제23권2호
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• pp.37-46
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• 1995

The substitution of carboxymethylated hydroxyl group in pulp revealed more hydrophilic than hydroxyl group. And then fibers were more flexible, swell more which leads to better conformation between fibers in turn this raise paper strength. In this paper, we tried to chemical modifyings of recycled fiber, OCCs(old corrugated containers). Many researchers have examined chemical modification of papermaking fiber by partial carboxymethylation(PCM) using a organic solvent processes. We made modified PCM processes adapted waters m replace of the organic solvent. Our testings for the optimum conditions on the new method, conditions as reaction time, temperature, liquor ratios were designed likely plant system. Freenesses(SR$^{\circ}$) were increased following on carboxyl content of the samples. Handsheets of untreated samples and partial carboxymethylated OCCs were made by optimum conditions on different concentrations of the reagent. As results, maximum 25% strength increasing effects were obtained by the new method.

• 농업과학연구
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• 제39권2호
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• pp.189-194
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• 2012

It is well-known fact that woodworking activity could contribute in enhancing creativity, scientific problem-solving ability, spatial perception ability and prosocial behavior of children. However, there is little chance that children experience woodworking at home or in kindergarten. This study was conducted to know how much children and adults have done woodworking in there daily life and how they perceived children's woodworking activity. Woodworking activities for children (N=207, 5 and 6 year old kids) with adults (N=271, only fathers) were carried out in 10 kindergartens of Cheongju. Actually, the survey result shows that very few children and adults experienced woodworking in their daily life. 62.8% of children and 34.3% of adults surveyed responded that they had never done woodworking. However, the greater part of children and adults evaluated the woodworking activity positively. Over 95% of children surveyed responded that their woodworking activity was fun and they want to play woodworking again. Over 73% of adults surveyed responded that children's woodworking activity was safe, and over 99% of adults surveyed responded that they can recommend children's woodworking activity to others. In conclusion, the development of safe tools and programs for children's woodworking activity helps its spread and activation.