• Title/Summary/Keyword: School Recycling

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Properties of the Sintered Eco-brick according to the Unburned Carbon Content of the Coal Briquette Ash (연탄재(煉炭滓)의 미연탄소(未燃炭素) 함량(含量)에 따른 소성(燒成) 에코벽돌 특성(特性))

  • Park, Hong-Kyu;Yoo, Seung-Woo;Jung, Moon-Young
    • Resources Recycling
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    • v.19 no.3
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    • pp.16-23
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    • 2010
  • Coal briquette use has dramatically increased because of high oil prices. Hence, it is necessary to develop an environment-friendly recycling technique of the coal briquette ash. The coal briquette ash contains a large amount of an unburned carbon content and a mullite with high thermal property, so it is considered to be used as raw materials of sintered eco-brick. This study aimed to investigate on how the unburned carbon affects properties of the sintered eco-brick. The eco-brick was mixed with the ratio of 50 wt% coal briquette ash having the unburned carbon 10.5 wt% and 50 wt% cullet, then being sintered at $950^{\circ}C$, which of the compressive strength was in line with the first class of the sintered clay brick standard(KS L 4201). In particular, the compressive strength of the sintered eco-brick was equal to the first class of the KS L 4201 despite the increase of mixing ratio for coal briquette ash with 1.0 wt% unburned carbon to 70 wt%.

Phosphorylation of REPS1 at Ser709 by RSK attenuates the recycling of transferrin receptor

  • Kim, Seong Heon;Cho, Jin-hwa;Park, Bi-Oh;Park, Byoung Chul;Kim, Jeong-Hoon;Park, Sung Goo;Kim, Sunhong
    • BMB Reports
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    • v.54 no.5
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    • pp.272-277
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    • 2021
  • RalBP1 associated EPS domain containing 1 (REPS1) is conserved from Drosophila to humans and implicated in the endocytic system. However, an exact role of REPS1 remains largely unknown. Here, we demonstrated that mitogen activated protein kinase kinase (MEK)-p90 ribosomal S6 Kinase (RSK) signaling pathway directly phosphorylated REPS1 at Ser709 upon stimulation by epidermal growth factor (EGF) and amino acid. While REPS2 is known to be involved in the endocytosis of EGF receptor (EGFR), REPS1 knockout (KO) cells did not show any defect in the endocytosis of EGFR. However, in the REPS1 KO cells and the KO cells reconstituted with a non-phosphorylatable REPS1 (REPS1 S709A), the recycling of transferrin receptor (TfR) was attenuated compared to the cells reconstituted with wild type REPS1. Collectively, we suggested that the phosphorylation of REPS1 at S709 by RSK may have a role of the trafficking of TfR.

A STUDY ON THE CHEMICAL RECYCLING METHOD OF METAL BRACKET (금속(金屬) Bracket의 화학적(化學的) 재생처리(再生處理) 방법(方法)에 관(關)한 연구(硏究))

  • Bang, Sang-Yong;Lee, Dong-Joo
    • The korean journal of orthodontics
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    • v.20 no.1
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    • pp.103-110
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    • 1990
  • Metal brackets were recycled by variable methods for economic reason. Such recycling methods had a great effect on bracket slot width and bonding strength. Therefore, the recycling methods that don't change the properties of original bracket were suggested. In this study, debonded brackets were recycled with 30 kinds of solvents and bracket surfaces were examined by S.E.M. (Super IIIA, ISI International Scientific Instruments, Japan) and Stero Microscope (Sz-Tr, Olympus Tokyo, Japan) methods. The following results were obtained. 1. Thermosetting resin adhesives (eq. $Monolok^{(R)}$, $Concise^{(R)}$) were swelled most in sulfuric acid (assays 95%) and slightly in alcohol groups. 2. The solvent was exchanged every 24 hours during the brackets were recycled with sulfuric acid (assays 95%). As the passage of time, the adhesives were removed more clearly, and after 72 hours adhesives were nearly detached from bracket base. 3. Chemical recycled metal bracket surface showed no irregular structure by S.E.M. method.

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Sustainability in PET Packaging

  • Shin, Yang-Jai;Kang, Dong-Ho
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.15 no.3
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    • pp.105-111
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    • 2009
  • In this work, source reduction of poly ethylene terephthalate (PET) packaging are discussed as aspect of sustainability, such as reuse, refill and recycling through the various treatment methods and historical studies for municipal solid waste (MSW) disposal. Since PET has good chemical, physical and mechanical properties, and provides good oxygen and carbon dioxide barrier properties, PET is one of the most widely used thermoplastic polyester in the U.S. and around the world. As the demand for non-renewable PET is increasing, several approaches have been developed to meet economical feasibility and environmental responsibility without degrading material performance. Several companies, such as Coca-Cola Co., Easterform Packaging Co. and Kraft, have tried to develop lightweight PET bottle, and some of lightweight PET bottles are already commercialized. Reuse and refilling for PET container is well developed in Europe, such as Denmark, German and Netherland by supportive legislation and policies. Recycling process is the best way to economically reduce PET waste. In consequence, advanced technique and further development must be provided due to increasing PET packaging waste.

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3D Racing Game for Education and Publicity of Resource Recycling (자원재활용 교육.홍보를 위한 3차원 레이싱 게임)

  • Jun, Byung-Hwan;Kim, Young-Won;Phan, The-Hung;Hyun, Ai-Ryun
    • Proceedings of the Korean Institute of Resources Recycling Conference
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    • 2003.10a
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    • pp.85-89
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    • 2003
  • 본 연구에서는 어린이들이 따분하고 어렵게 느낄 수 있는 재활용 교육 방식을 지양하고, 재활용품의 수집 및 분류 그리고 재활용 공정을 자연스럽게 체험할 수 있도록 하기 위해 어린이들의 흥미를 유발시키고 과학적인 호기심을 충족시키는 방식으로 3DMax와 DirectX를 이용하여 3차원 재활용 레이싱 게임을 개발한다. 결과적으로, 재활용 관련 전시관에서 어린이들이 직접 사용해 볼 수 있는 자료로 활용되거나 교육기관 및 관련 관공서에서 홍보 및 교육용 매체로 활용될 수 있을 것으로 기대된다.

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Optimal Operation for Green Supply Chain with Quality of Recyclable Parts and Contract for Recycling Activity

  • Kusukawa, Etsuko;Alozawa, Sho
    • Industrial Engineering and Management Systems
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    • v.14 no.3
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    • pp.248-274
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    • 2015
  • This study discusses a contract to promote collection and recycling of used products in a green supply chain (GSC). A collection incentive contract is combined with a reward-penalty contract. The collection incentive contract for used products is made between a retailer and a manufacturer. The reward-penalty contract for recycling used products is made between a manufacturer and an external institution. A retailer pays an incentive for collecting used products from customers and delivers them to a manufacturer with a product order quantity under uncertainty in product demand. A manufacturer remanufactures products using recyclable parts with acceptable quality levels and covers a part of the retailer's incentive from the recycled parts by sharing the reward from an external institution. Product demand information is assumed as (i) the distribution is known (ii) mean and variance are known. Besides, the optimal decisions for product quantity, collection incentive of used products and lower limit of quality level for recyclable parts under decentralized integrated GSCs. The analysis numerically investigates how (1) contract for recycling activity, (ii) product demand information and (iii) quality of recyclable parts affect the optimal operation for each GSC. Supply chain coordination to shift IGSC is discussed by adopting Nash Bargaining solution.

A STUDY OF BONDING STRENGTH AND CHANGE OF BRACKET SLOT WIDTH OF CHEMICALLY RECYCLED METAL BRACKETS (화학적(化學的)으로 재생(再生)된 금속(金屬) bracket의 접착(接着) 강도(强度)와 slot폭경(幅徑) 변화(變化)에 관(關)한 연구(硏究))

  • Ko, Young-Sam;Lee, Dong-Joo
    • The korean journal of orthodontics
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    • v.20 no.2
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    • pp.283-291
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    • 1990
  • The purpose of this study was to measure and compare tensile and shear strength for 4 types of new direct-bonding brackets and same brackets after recycling and to evaluate the change of bracket slot width after recycling. Four types of new direct-bond brackets were bonded to recently extracted human premolar teeth and the tensile and shear strength was measured by Universal Testing Machine. The brackets were recycled by chemical process and the tensile and shear test was repeated. To evaluate the change of the bracket slot width, slot width was measured by the Topcon Universal Measuring Microscope before and after recycling. Following results were obtained: 1. There was no satistically significant difference between the tensile and shear strength of recycled brackets and those of new brackets. 2. In both new and recycled brackets, the tensile and shear strength of perforated base bracket was lower than those of photoetched, foilmesh and contou-lok mesh base brackets. (P<0.01) 3. There was no statistically significant difference in bonding strengths of control group bonded only once and two times. 4. There was no statistically significant difference in the change of the bracket slow width after recycling process. 5. Of the failure, the combination type (58%) in the tensile strength and the tooth adhesive interface (65%) in the shear strength was the most common type.

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Risk assessment in international EV battery closed loop supply chain: developing a conceptual framework

  • Nataliia Grekova;Dong-WookKwak
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2022.06a
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    • pp.201-203
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    • 2022
  • Increasing global market of used electric vehicle (EV) battery encourages international firms to establish its subsidiary companies or business units specializing in battery recycling. Such kind of companies predominantly use closed loop supply chain (CLSC) for their operations of battery manufacturing and used battery recycling/reusing in global scale. However, EV battery recycling, as a relatively new industry, makes its global CLSC be exposed to various types of risks, which leads to inefficiency of supply processes and makes supply chains more complicated and vulnerable. Identifying, evaluating, and analyzing possible risks in CLSC has a great importance for optimization and increasing effectiveness for the global supply chain of used EV battery. Itwill assist to elaborate the efficient CLSC management and possible risk mitigation strategies to keep the global EV battery supply chain resilient and sustainable. This study aims to develop a conceptual framework for risk assessment in this new sector. Therefore, it will populate the framework with possible failure modes identified from various literature on EV battery recycling and closed loop supply chains so that future research can validate and utilize the conceptual framework.

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Study on the recycling of the construction wastes and reformation of the system (건설폐기물의 재활용 활성화 방안에 관한 연구)

  • Kim, Young-Jun;Chung, Myung-Hee
    • Journal of the Korea Organic Resources Recycling Association
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    • v.20 no.2
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    • pp.27-35
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    • 2012
  • Concrete produced from the construction wastes has been largely used as the recycled aggregate. These wastes, however, is mostly used as filling materials. For any recycled aggregate like waste concrete to be used as normal construction materials, it is necessary to actively find out the proper market places as much as possible with the improved quality. In this study, we have investigated the present status on the occurrence and treatment of both domestic and abroad construction wastes, and also the recycling status and related legislation with some inhibitory factors. Based on these investigations, we suggested some effective ways to increase the recycling of construction wastes.