• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.67-72
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• 2004

Wood/polyethylene panels were manufactured from Populus alba × glandulosa particles and low density polyethylene particles at three mixing rates, 50:50, 60:40, and 70:30. A total of 15 wood/polyethylene panels was made at 145℃ and 5 minutes hot-press time. Wood/polyethylene panels were tested for internal bond, bending, and dimensional stabilities such as thickness swell and water absorption. Panel performance data were analyzed using the SAS programing package. The test results of the wood/polyethylene panels showed that as the polyethylene mixing rates were increased, the panel property values increased. Based on panels' dimensional stabilities, the optimum wood/polyethylene mixing ratio appeared to be 60:40.

• The Optical Journal
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• s.135
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• pp.17-19
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• 2011

광학산업에 관한한 척박했던 국내 여건 속에서도 지난 1997년 자체 기술연구소를 통해 국내 최초로 카메라 폰에 들어가는 비구면 플라스틱 렌즈를 개발하며 연간 1억 개가 넘는 카메라 렌즈를 만들어내는 세코닉스(대표 박원희, www.sekonix.com)는 이제 세계시장에서도 주목받는 글로벌 기업으로 성장했다. 매출액의 15%를 연구개발비로 출연할 만큼 기술개발에 매진한 결과 플라스틱 렌즈가 들어가는 주요 영상기기 및 응용기기에는 세코닉스의 기술이 심어졌다고 해도 과언이 아니다. 이처럼 앞선 미래를 바라보는 연구개발을 통해 무한질주를 거듭하고 있는 세코닉스 기술연구소를 다녀왔다.

• The Optical Journal
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• s.102
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• pp.46-48
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• 2006

2002년 설립된 씨에이프로(주)(대표·이길호/www.caepro.co.kr)는 플라스틱 사출성형해석 솔루션 전문기업으로서 현재 사출성형해석 솔루션인‘3D-TIMON’을 한국 및 중국에 독점공급하고 있으며 이와 관련된 컨설팅 서비스를 제공하고 있다. 현재 다수의 광학관련 중소기업으로부터 구매 검토를 위한 BMT를 통해 결과의 신뢰도와 현업 적용가능성에 대해 좋은 호응을 받고 있는 가운데 국내에‘3D-TIMON’을 활용한 초정밀 광학부품 사출성형과 관련한 활발한 교육사업을 펼치고 있으며‘3D-TIMON’이 향후 플라스틱 광학부품의 양산기술 표준솔루션으로 자리잡을 것을 기대하고 있다.

• Journal of Energy Engineering
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• v.14 no.2 s.42
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• pp.159-166
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• 2005

In Korea, although the generation of waste plastic has been increasing, the rate of recycling is considerably low and moreover, there is no suitable method for the treatment of waste plastics. However, pyrolysis, which is appropriate for the treatment of highly polymerized compounds, such as plastics, has recently gained much interest. In this study, a property of the products from the pyrolysis of mixed waste plastics, with a possible practical use for the recycling oil produced, were assessed. First of all, in order to investigate the pyrolysis characteristic of waste plastics, TGA (Thermogravimetric analysis) and DCS (Differential Scanning Calorimetry) were performed on a number of different plastics, including PP, LDPE, HDPE, PET and PS, as well as others. According to the result, it appeared that PP was the most efficiently pyrolyzed by changing the temperature, followed by LDPE, HDPE, PET, PS and the other plastics, in that order. From the results, the optimum conditions f3r pyrolysis were set up, and the different waste plastics pyrolyzed. The recycling oil produced from the flammable gases generated during the pyrolysis was com-pared with fuel oil by an analysis using the petroleum quality inspection method on KS(Korea industrial Standard). The results of the analysis showed the recycling oil was of a similar standard to fuel oil, with the exception of the ignition point, with a quality somewhere between that of paraffin oil and diesel fuel. With respect to these results, the quality of the recycling oil produced by the pyrolysis of waste plastics was suf-ficient for use as fuel oil.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.702-708
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• 2017

The heat generation rate in a telecommunications cabinet keeps increasing due to the increased usage of mobile devices. Insufficient removal of the heat increases the cabinet temperature, which results in the malfunction of the electronic devices. In this study, tests were conducted on aluminum and plastic heat exchangers for cooling a telecommunications cabinet, and the results were compared with theoretical predictions. The aluminum heat exchanger comprised counter flow parallel channels with 4.5-mm pitch, and the plastic heat exchangers comprised cross or cross-counter flow triangular channels with 2.0-mm pitch. The volume of the cross flow heat exchanger was the same as that of the aluminum heat exchanger, and the volume of the cross-counter heat exchanger was 33% larger than that of the aluminum heat exchanger. The results show that the heat transfer rate is the highest for the cross-counter heat exchanger and lowest for the aluminum one. The temperature efficiency of the cross-counter heat exchanger was 56% higher than that of the aluminum one and 20% higher than that of the cross flow heat exchanger. The pressure drop of the cross-counter heat exchanger was approximately the same as that of the aluminum one. The heat exchange efficiency was the highest for the cross-counter heat exchanger and lowest for the cross flow heat exchanger. The theoretical analysis somewhat overestimated or underestimated the data.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.1
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• pp.109-119
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• 2002

This study is to estimate that food waste bags with biodegradable plastic are really decomposed by microorganism in composting with food waste and to examinate how biodegradable plastic affects composting. 6 kinds of 30%, 4 kinds of 100% and 2 kinds of none biodegradable plastics were used in d1is study. In 30% biodegradable plastics the highest Degradation rare is 6% in meso-condition and 10% in thermal-condition. Srain at auto break decreased to 150% in meso-condition and 120% in thermal-condition. Stress at max load were also reduced to $180kgf/cm^2$ in mesocondition and $200kgf/cm^2$ in thermal-condition. Usually, LLDPE decreased larger than HDPE in physical characreristics but HDPE is higher in degradation rate. 1n stain at auto break and stress ar max load 100% biodegradable plastic declined to 230% and to $380kgf/cm^2$ in meso-condition and to 440% and to $400/cm^2$ in thermal-condition respectively. 100% biodegradable plastics showed higher biodegradation and decomposition then 30%. They appeared clearly through SEM observation. As a result, it was not appropriate to use 30% biodegradable plastics as food waste bag because they were not decomposed perfectly. It is possible to use 100% biodegradable plastic as it but cost is too high. So development of technique is needed.

• Journal of Mushroom
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• v.22 no.1
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• pp.31-36
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• 2024

Plastics are widely used in industries in human society and because of their structural stability, degradation is a serious global issue. To estimate the degradation of plastic, 31 edible mushrooms were cultured with the selected plastic films (polyethylene [PE], polystyrene [PS], and poly(ethylene terephthalate) [PET]) for 3 months at 25 ℃. Measuring the weight of the films showed that four species of mushrooms, namely Porostereum spadiceum, Ganoderma lucidum, Coprinellus micaceus, and Pleurotus ostreatus, exhibited the highest degrees of plastic degradation. In addition, the mushrooms and fungi that exhibited the most significant plastic degradation were cross-cultured to promote this degradation. As a result, cross-cultivation of G. lucidum and Aspergillus niger showed a weight loss of 2.49% for the PET film. For the PS film, Aspergillus nidulans showed a weight loss of 4.06%. Cross-cultivation of A. nidulans and C. micaceus, which showed a weight loss of 2.95%, was noted as an alternative for PS biodegradation, but is harmful to humans. These bio-degradation effects of edible mushroom will contribute to the development of alternatives for eco-friendly plastic degradation.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.556-559
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• 2006

벌크형태의 태양전지 기판을 대체할 목적으로 연성기판을 적응한 태양전지 개발이 활발하게 진행되고 있으며, 주재료는 플라스틱 기판, 금속기판 등이 있다 그러나 기존의 연성기판인 플라스틱의 경우 열과, 내구성, 화학약품에 약하다는 단점이 있으며, 금속기판은 높은 생산원가, 박막화의 어려움 등의 문제를 안고 있다 이러한 문제를 극복하기 위해 전주성형법으로 제조된 철-니켈계 연성기판을 개발하였다. 이 연성기판의 경우 고온의 공정조건에서도 열팽창율이 플라스틱 기판보다 낮으며, 기존의 금속기판 보다 저렴한 생산단가로 쉽게 극박화 할 수 있다는 것이다. 전주성형법을 적용하여 40Ni, 45Ni, 52Ni 연성기관을 제조하였으며, TMA 장비를 사용하여 각 연성기판의 열팽창 계수를 측정한 결과 6.36, 6.78, $10.93{\mu}m/m^{\circ}C$로 기존의 연성기판인 플라스틱, 금속에 비해 낮은 열팽창 계수를 가짐으로서 고온 공정 중에 안정성 요구를 충분히 충족시킬 수 있다.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.307-312
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• 2015

Mammography improves image quality that is on the increase day by day and get a picture with the pressure it is essential to reduce the dose. However, because due to the thickness of the cuff itself may increase the dose scattering lines is necessary study on the cuff material. Material that is currently being used in clinical Polycarbonate is a plastic and family. If you try to reduce the exposure of patients than itgie need to consider for the better material in this study to compare against a radiolucent line for amorphous plastic material of the plastic. results radiolucent and half layer, transmitting dose Pixel values HIPS, GPPS, ABS, Tritan, PC, PMMA showed high results in the net.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.637-641
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• 2007

화석연료의 고갈이 가시화됨에 따라 이를 해결하기 위한 대체에너지원의 확보를 위해 다양한 연구가 수행되어 왔다. 본 연구에서는 폐기물 특히 플라스틱 폐기물의 안정적인 처리 및 청정가스의 생산방법을 연구하기 위해서 선행적으로 플라스틱 폐기물의 열분해 특성을 조사하였으며, 그 반응모델을 제시하여 열분해로의 설계인자의 도출하고자 하였다. 대상 폐 플라스틱류로서 PE, PP, PVC, RPF 등을 이용하였고, 열중량분석기와 tube furnace를 통해서 온도에 따른 분해반응 특성을 확인하였다. 열분해 특성조사를 한 결과 PE, PP 등은 잔류 char가 없이 $400^{\circ}C$ 전후에서 완전 분해하였으며, PVC의 경우 $400^{\circ}C$ 이후에도 약 20% 이상의 char가 잔류함을 확인하였고, RPF의 경우에도 약 10%의 char이 잔류함을 확인하였다. 또한 각각의 열분해 특성을 DTG/TGA분석을 통해서 적정체류시간을 구할 수 있었고, 다단열분해 가스화기를 이용하여 합성가스를 제조한 결과 2500 kcal / $Nm^3$의 높은 발열량을 가진 합성가스를 제조할 수 있었다.