• 열처리공학회지
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• 제12권2호
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• pp.108-116
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• 1999

Gray cast iron with a high damping capacity has been used for controlling the vibration and noise in various mechanical structures. Nevertheless, its usage has been often restricted due to its poor tensile strength. Therefore, it is necessary to improve tensile strength at the expense of a loss in damping capacity. This study is aimed at finding the best combination of tensile strength and damping capacity by varying austempering time and temperature range from $320^{\circ}C$ to $380^{\circ}C$ after austenization at $900^{\circ}C$ for 1hr. The effect of austempering condition on hardness and the volume fraction of retained austenite is investigated as well. The results obtained are summarized as follows : (1) With an increase in austempering temperature, both tensile strength and hardness decrease while damping capacity improves. (2) Austempering at $350^{\circ}C$, resulting in a mixture of upper and lower bainite with partially retained austenite, exhibits the optimum combination of tensile strength and damping capacity.

• Journal of Korean Neurosurgical Society
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• 제42권2호
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• pp.135-140
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• 2007

It is not the best way to treat a hopeless patient with life-sustaining medical devices until the heart beats stop. Advanced medical technology may prolong the life for a significant period without recovery from the disease. However, it would give an unbearable economic burden to the family and the society. In 2006, we decided not to operate 9 patients with traumatic intracranial hematomas. We examined those patients with special references to possible legal and ethical problems. It is reasonable to withhold a treatment after documentation that the family never wants any life sustaining treatment when the treatment does not guarantee the meaningful life.

• Mycobiology
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• 제30권4호
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• pp.208-212
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• 2002

For comparison of mycelial colonization of Phellinus linteus on logs, several techniques of inoculation were tested; sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation. The mycelial colonization of P. linteus on logs was good in the treatment of sterilized short log inoculation, but poor in the traditional methods such as drilling inoculation and log-end sandwich inoculation. The initial mycelial growth and the full mycelial colonization of P. linteus in logs were the best in case of 20 cm logs under the condition of 42% moisture content. Also, the initial mycelial growth of P. linteus was accelerated over 12 hours of sterilization. Burying method of logs after $5{\sim}6$ months of incubation was the best for formation of basidiocarps of P. linteus. The formation of fruiting body of P. linteus was quite good in the cultivation house at $31{\sim}35^{\circ}C$ and over 96% of relative humidity.

• 반도체디스플레이기술학회지
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• 제10권3호
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• pp.7-13
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• 2011

In Korea, the car mobile phone service had started in 1961 and with this Korea Mobile Telecommunications Services was established in 1984. Its service was mainly focused on the mobile phone service for the car which led the popularity of the full-scale mobile phone service. There are many kinds of materials, colors and patterns which are the elements of surface coating techniques. In light of that, we are focused on the UV coating that is ranked as an important part of the techniques in this study. In the first, the use of various materials for the cellular phone and surface processing techniques for the cellular phone were searched. On the basis of the results, the experiments of actual consumer experience with the exfoliation of the surface were done and through that we proposed the best way of processing the surface for the cellular phone and the materials. The result of the Wear Test showed that thick coating was detached more slowly and each company differed in their results with UV paints despite the same thickness of UV coating. The seal (UV) exfoliation of cellular phone is deeply related with the film thickness and the film formation when the users use the cellular phones and the exfoliation of the cellular phone surface will be decreased if the manufacturers meet the best conditions for the cellular phone.

• 자원환경지질
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• 제38권5호
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• pp.599-606
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• 2005

전 세계적으로 수많은 나라의 지하수에 용존 되어있는 비소는 매우 독성이 강한 오염물질이다. 이로 인해서 지하수에 있는 비소를 제거하기 위한 수많은 처리기술들이 개발되고 있다. 미국 환경청에서는 비소를 처리하기 위한 가장 적합한 기술로써 여러 가지의 기술들을 추천하고 있다. 미국 환경청의 분류를 기준으로 비소처리기술은 침전, 멤브레인, 이온교환 및 흡착의 네 가지 처리기술로 나눌 수 있다. 미국에서 최근 $50{\mu}g/L$에서 $10{\mu}g/L$로의 비소 음용수 기준의 개정은 비소오염지하수에 있는 비소를 제거하기 위한 기술의 선택과 적용에 많은 영향을 주고 있다. 침전기술은 비소처리를 위해서 가장 많이 이용되는 기술로 대규모 수처리 설비로 비소를 처리하는데 적용할 수 있는 있지만, 멤브레인, 이온교환 및 흡착기술은 소규모 수처리 시설에 사용된다 최근에 미국과 유럽에서는 설치비와 유지비가 적고 운전이 간편한 흡착기술을 이용한 소규모 비소처리 시설에 많은 관심을 가지고 있는 추세이다 비소로 오염된 지하수를 처리하기 위한 처리기술들의 원리와 비소제거에 영향을 미치는 인자 및 실제 처리시설들의 비소처리효율을 본 논문에서 소개하고자 한다.

• 생태와환경
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• 제38권3호통권113호
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• pp.281-288
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• 2005

폐수배출시설별 BAT 평가제도는 폐수특성을 고려한 배출시설별 배출허용기준 설정, 오염총량관리기본계획 및 시행계획에 따른 오염부하삭감 가능량 산정, 신규오염물질에 대한 배출허용기준 산정 등 효율적인 산업폐수관리를 위해서 도입할 필요가 있다. 본 연구에서는 외국사례와 국내 폐수배출시설들의 현황 등을 조사하여 국내여건에 적합한 BAT 평가방안을 제시하였다. 본 평가절차의 핵심은 폐수배출시설별 처리시설에 대한 환경인자, 경제적 수용가능성, 기술적 인자 및 경제성 등을 객관성 있고 전문적인 판단이 가능토록 한데 있다. 본 BAT 평가방안은 처리수준에 근거한 폐수배출시설별 배출허용기준마련 및 오염총량관리를 위한 기초 자료로 활용할 수 있으며, 신규오염물질 및 유해오염물질의 배출허용기준 마련 등 정책적${\cdot}$법적 제도개선에 유용하게 활용할 수 있을 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권1호
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• pp.1-7
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• 1998

A total of 120 pigs $(L\;{\times}\;LW\;{\times}\;D)$ averaged 14.16 kg of body weight were reared under six dietary treatments to evaluate the effects of amino acid supplementation on their performances. Treatments were 1) 18% CP diet (control); 2) 15% CP+0.28% Lys (B, 15L); 3) B+0.06% Met (15LM); 4) B+0.13% Thr (15LT) ; 5) B+0.06% Met+0.13% Thr (15LMT); 6) B+0.06% Met+0.13% Thr+0.05% Trp (15LMTT). Each treatment had 4 replicates with 5 pigs per replicate. The daily weight gains were statistically similar in 15LMT, 15LMTT and control groups. Threonine and methionine supplementation resulted in improved growth performance and nutrient digestibilities, while tryptophan supplementation had little beneficial effect. However, the best feed conversion was found in the control group. Dry. matter and CP digestibilities were improved in the 15LMT and 15LMTT groups. Gross energy, crude fat and phosphorus digestibilities were not affected by the treatment. Among the 15% CP groups, nitrogen digestibility showed the tendency to be increased as the more synthetic amino acids were added. Dry matter and nitrogen excretions were significantly reduced by feeding low protein, amino acid fortified diets, while phosphorus excretion was not influenced. Essential amino acids digestibility was higher in 15LT, 15LMT and 15LMTT groups and lower in the control. The 15LT group showed the best lysine digestibility, and methionine digestibilities were higher in all treated groups than control one. Threonine digestibilities higher in 15LT 15LMT, and 15LMTT than the control. The result shows that threonine and methionine should be added to the diet containing 15% CP diet, fortified with lysine to get same performance of 18% CP diet.

• 한국염색가공학회지
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• 제29권3호
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• pp.122-130
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• 2017

In the direct digital textile printing process, the pre-treatment process is an essential condition for products by forming a clear pattern by sticking and penetration of DTP dye without spreading on the fabric. Recently, pre-treatment agent is changing from high viscosity to low viscosity in order to reduce defects of fabric during pre-treatment process. In this study, pre-treatment agent of acrylic polymer with low viscosity(less than 50cps) was prepared according to the solid content of the polymer, pre-treated on the cotton fabric, and direct DTP printing was performed to compare the color and sharpness. As a result, it showed high color at a viscosity of 50cps or less. When the solid content of the polyacrylic acid having a high molecular weight(A1) was 2.5wt%, when the solid content of the polyacrylic acid having a low molecular weight(A2) was 1 - 1.5wt%, the color was the best. And when the solid content of A1 and A2 was 1.5wt%, the degree of spreading was small and A1 was superior to A2 at the sharpness.

• 접착 및 계면
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• 제4권2호
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• pp.21-29
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• 2003

Hot AC anodising has been evaluated us pre-treatment for aluminium prior to structural adhesive bonding. Phosphoric and sulphuric acid hot AC anodising showed very promising adhesion promoter capabilities with durability comparable with the best standard DC anodising procedures. AC anodising does not required etching prior to anodising and offers u pre-treatment time down to 20 seconds. The interface/interphase between the aluminium substrate and the adhesive was investigated in order to get a better understanding of the involved adhesion mechanisms and to explain the long-tenn properties. The alkaline medium formed at the oxide layer/adhesive interface has been shown to induce a partial dissolution of the oxide layer leading to the formation of metallic ions which diffuse in the adhesive (EPMA measurements). The effect of diffusion of the Al ions on adhesion and joint durability is still uncertain but studies showed that pre-bond moisture affected the joints durability and to some extent the diffusion length. specially for DC anodised samples. So far no direct correlation could be established between the diffusion length d and the joints durability but new trials with better control over the elapsed time between bonding and adhesive curing are expected to help getting a better understanding of the involved mechanisms.

• 한국포장학회지
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• 제18권1_2호
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• pp.9-14
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• 2012

곶감은 상온 유통 시 분과 갈변이 발생하고 조직이 단단해지는 현상이 일어난다. 이런 문제점들을 해결하기 위한 방법으로 계피추출액에 침지 후 포장재에 따른 저장 곶감의 품질변화를 $0^{\circ}C$에서 160일 저장하면서 조사하였다. Nylon/LDPE 필름으로 포장시 가장 적은 변화를 보였다. 이 포장구에서 중량감소도 거의 없었으며, 분과 곰팡이 발생도 거의 발생하지 않았고, 갈변도와 경도 또한 가장 적은 변화를 나타내어 상품으로써의 가치가 가장 높았음을 알 수 있었다. 계피추출물 처리가 품질유지에 효과를 가지는 것으로 나타났다.