• 한국주조공학회지
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• 제25권5호
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• pp.203-208
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• 2005

The main emphasis of this study is to optimize the process variables for manufacturing aluminum foam materials by direct foaming of remelted aluminum scraps. Aluminum foams were fabricated from two different raw materials, pure aluminum and used beverage cans. For both cases, $TiH_{2}$ was used as a foaming agent. Calcium was added as a thickener for the foaming of pure aluminum and no thickener was added for that of used beverage Cans because the pre-existing oxides of the used beverage cans are used as a thickener. Calcium and $TiH_{2}$ content varies from 0.5wt.% to 2.0wt.% and from 0.5wt.% to 1.5wt.%, respectively. The processing conditions, such as the effect of calcium on the melt viscosity, foaming temperature, and the optimum amount of the foaming agent with regard to the melt viscosity were discussed.

• 디지털산업정보학회논문지
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• 제19권1호
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• pp.119-127
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• 2023

Recently, deep learning has been used in the development of various institutional devices and services to help the visually impaired people in their daily lives. This is because not only are there few products and facility guides written in braille, but less than 10% of the visually impaired can use braille. In this paper, we propose a system that recognizes beverage cans in real time and outputs the beverage can name with sound for the convenience of the visually impaired. Five commercially available beverage cans were selected, and a CNN model and a YOLO model were designed to recognize the beverage cans. After augmenting the image data, model training was performed. The accuracy of the proposed CNN model and YOLO model is 91.2% and 90.8%, respectively. For practical verification, a system was built by attaching a camera and speaker to a Raspberry Pi. In the system, the YOLO model was applied. It was confirmed that beverage cans were recognized and output as sound in real time in various environments.

• 자원리싸이클링
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• 제9권2호
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• pp.3-10
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• 2000

알루미늄 폐캔은 중요한 재활용 자원으로서 알루미늄 캔용 원소재 판재는 물론 알루미늄의 국내소요량을 전량 수입에 의존하고 있는 우리나라로서는 활용 가능한 알루미늄폐캔의 재활용율을 높여야 하는 것은 외화절약과 환경보호 측면에서 대단히 중요하다. 사용한 알루미늄 캔을 다시 캔으로 재활용 하는 단계는 폐캔의 수집, 파쇄, 선별, 도료제거, 용해 및 2차지금을 제조하는 단계와 이 2차지금을 이용하여 열처리, 열간 및 냉간압연, 중간소둔처리 등을 거쳐 다시 캔을 성형하는 2단계로 나눌수 있다. 본 자료에서는 이러한 알루미늄 캔의 재활용 기술에 대한 우리나라와 선진국들의 현황과 전망을 소개하였다.

• 자원리싸이클링
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• 제9권2호
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• pp.46-52
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• 2000

사용한 알루미늄 캔을 다시 캔으로 재활용 하는 단계는 폐캔의 수집, 폐쇄, 선별, 도료제거, 용해 및 2차지금을 제작하는 단계와 이 2차지금을 이용하여 열처리, 열간 및 냉간압연, 중간소둔처리 등을 거쳐 다시 캔을 성형하는 단계로 나눌수 있다. 본 연구에서는 2차지금에서 켄성형까지의 과정에서 중요한 요소인 미세조직 및 열간압연후의 집합조직에 미치는 합금원소의 영향을 조사하였다. 폐캔을 이용하여 다시 캔을 제조하기 위한 판재가공에서는 주조시 형성된 공석상들의 구형화와 $\alpha$상 ($Al_{12}(Fe, Mn)_3Si)$)으로의 상변화 제어가 필요한데, 열처리에 의한 석출거동을 조사하여 $615^{\circ}C$, 5시간 균질화 처리조건에서 최적의 미세조직을 얻을 수 있었다. 2차자금을 이용하여 캔소재를 제조한 결과, Mn량이 증가할수록 고용효과에 의해 전기전도도는 감소하고 집합조직의 발달이 억제되었다. Si 과 Fe는 금속간화합물 형태로 존재하며, 함량이 증가할수록 석출효과에 의해 전기전도도가 증가하고 변형집합조직의 발달이 촉진되었다. 캔은 냉간압연후 다른처리 없이 바로 제조되기 때문에 집합조직의 제어는 열간압연 및 소둔처리 단계에서 제어되어야 한다.

• 소성∙가공
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• 제24권2호
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• pp.115-120
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• 2015

Deep drawing of cylindrical cups is one of the most fundamental and important processes in sheet metal forming. Circular cups are widely used in industrial fields such as automobile and electronic appliances. Some of these cups are formed by a one-stage process, others such as battery cases and beverage cans are made by a multi-stage process. In the current study the multi-stage deep drawing of aluminum sheet metal is examined. The process consists of two deep drawing operations followed by two ironing operations. The press die, which can be used for the four-stage forming process, was manufactured allowing punch and die components to be easily changed for various experiments. The rolling direction of both the sheet and the drawn cups was always positioned toward the horizontal x-direction on the die face to minimize experimental errors during the progressive forming. The dimensional accuracy of the cylindrical cups formed at each stage and the earing defect due to the anisotropy of sheet were investigated. The influence of anisotropy on the thickness distribution was also examined. Both the thickness and the outer diameter of the cups were measured and compared for each set of experimental conditions. It was found that the dimensional accuracy of cups rapidly improves by employing the ironing process and also by increasing the amount of ironing.

• 자원리싸이클링
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• 제26권4호
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• pp.71-78
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• 2017

본 연구는 UBC 재활용 용해공정 중 발생한 블랙 드로스 내 금속 알루미늄을 회수하기 위해 압축 및 충격 파쇄 공정에 따른 알루미늄 회수율에 대하여 조사하였다. 초기 알루미늄 블랙 드로스는 대부분 구형의 형상으로 약 10~40 mm 크기였다. 또한 블랙 드로스의 주요 구성 성분은 할라이트(NaCl), 실바이트(KCl), 스피넬($MgAl_2O_4$) 및 알루미나($Al_2O_3$)로 나타났다. 알루미늄 금속의 회수율 시험은 서로 다른 파쇄 기구를 갖는 죠 크러셔와 햄머밀 공정으로 진행하였다. 파쇄 기구에 따른 알루미늄 금속 회수 실험결과, 죠 크러셔 공정은 금속과 비금속 혼합물을 분리할 수 있었으나 햄머밀 공정은 금속과 비금속의 분리가 어려운 것으로 관찰되었으며 알루미늄 블랙드로스 내 금속 알루미늄을 회수하기 위한 파쇄 공정은 죠 크러셔 공정이 더 효과적인 것으로 보여진다.

• 자원리싸이클링
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• 제11권6호
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• pp.31-37
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• 2002

폐알루미늄 캔으로 제조된 2차지금과 신지금의 혼합비율에 따라 캔용 소재를 주조하고 미세조직을 조사하였다. 또한 주조후 열처리에 따른 상변화의 거동을 조사하였다. 2차지금의 혼합비율(20, 30, 40, 50, 60%)에 따라 캔용 소재를 전기로로 용해하고, ceramic filter를 사용하여 주조하였다. 주조후에는 주조조직 제어를 위해 균질화 열처리($615^{\circ}C$$\times$10hrs)를 하였다. 주조상태에서는 $\alpha$ 상($Al_{12}$ $(Fe,Mn)_3$Si), $\beta$상($Al_{6}$/(Fe,Mn)), 그리고 미세한 $Mg_2$Si상이 알루미늄 기지에 존재하며, 특히 가공성에 나쁜 영향을 미치는 것으로 알려진 $\beta$상이 많이 존재하였다. 그러나 균질화 열처리에 의해 이러한 $\beta$상은 유해성이 없는 $\alpha$상으로의 상변태가 일어났다. 기지내의 미세한 $Mg_2$Si상도 열처리에 의해 $\alpha$상으로 변화하였다. 주조시 여과된 조직을 분석한 결과 Fe, Cu, Si 등의 금속간화합물이 검출되었다.

• Clinical and Experimental Reproductive Medicine
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• 제38권2호
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• pp.75-81
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• 2011

Objective: Bisphenol A (BPA) is a chemical used extensively to manufacture plastics and epoxy resin liners for food and beverage cans. BPA, with properties similar to estrogen, has endocrine-disrupting effects. In the present study, we examined the effects of early prepubertal BPA exposure on the onset of puberty and reproductive parameters such as estrous cycle and reproductive organ weights in female mice. Methods: Female mice were injected subcutaneously at postnatal day (PND) 8 with BPA (0.1, 1, 10, 100 mg/kg) in sesame oil or with sesame oil alone. Body weight was measured from PND 10 to 70. Vaginal opening and estrous cycle were monitored from PND 20 to 29. Animals were sacrificed at PND 25, 30, and 70, and the ovary and uterus weights were measured. Results: Early prepubertal exposure to BPA (10 and 100 mg/kg) significantly decreased body weight from PND 18 to 30. BPA treated mice at testing dose levels showed early opening of the vagina compared to the control group. The number of estrous cycle and days of estrus were significantly decreased in high dose (100 mg/kg) BPA treated mice. The ovary weight at PND 25 and 30 was significantly decreased in all BPA treatment groups. Conclusion: Early prepubertal exposure to BPA accelerated the onset of puberty but decreased reproductive parameters in female mice.

• Toxicological Research
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• 제34권3호
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• pp.231-239
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• 2018

Bisphenol A, an everywhere chemical, is applied as a plasticizer in polycarbonate plastics, which often used in our everyday products and in epoxy resins as protective coatings and linings for food and beverage cans for decades. Human exposure to BPA may lead to adverse effects by interfering with oestrogen receptors. Our present study was conducted to investigate the protective effects of selenium (Se) and vitamin E (Vit E) on BPA-induced damage in the liver of male rats. Animals were randomly divided into four groups: the first group received olive oil and served as control. The second group received both (Se + Vit E) (0.5 mg/kg diet; 100 mg/kg of diet). The third one treated orally by (10 mg/kg b.w.) of BPA. The last group received (Se + Vit E) (0.5 mg/kg diet; 100 mg/kg of diet) concomitantly with (10 mg/kg b.w.) BPA. Exposure to BPA for three weeks engendered a hepatic disorder. An increased AST and ALT enzymatic activity was noticed in BPA-treated group as compared to other groups. Furthermore, a change in glucose, cholesterol, LDL-C, HDL-C, albumin, and bilirubin level was remarkable. Moreover, exposure to BPA increased malondialdehyde levels while reduced gluthatione content was decreased in the liver homogenate. A decrease in glutathione peroxidase, glutathione s-transferase and catalase activities was observed in the same group. Administration of selenium and vitamin E through the diet in BPA treated rats ameliorated the biochemical parameters cited above. In addition, an improvement in activities of liver enzymes was recorded. The histological findings confirmed the biochemical results. The model of this study that we employed characterized the relationships between BPA-induced hepatotoxicity and its alleviation by natural antioxidants like selenium and vitamin E.