• Title/Summary/Keyword: E-Waste Management

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An analysis of research trends on living modified organisms in Korea through questionnaire surveys (전수조사를 통만 국내 유전자변형생물체의 연구 동향 분석)

  • Yi, Hoon-Bok;Choi, Kyung-Hwa;Chung, Soon-Gee;Kim, Yong-Ho;Kim, Hwan-Mook
    • Journal of Plant Biotechnology
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    • v.35 no.1
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    • pp.31-39
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    • 2008
  • We analyzed the current research trends of living modified organisms (LMO) by questionnaires in the interest of making biosaftey laws and policies in Korea. We executed a pre-survey at the Crop Functional Genomics 2004 conference and obtained LMO research information from 423 LMO research organizations, including 32 national research institutes, 314 universities, and 77 industries. We found that the total 59 kinds of hosts including 26 kinds of plants, 15 kinds of animals, and 18 kinds of microbes were used for LMO research and E. coli was the most common host. The risk of the most experimental hosts was below a biosafety level of 1 (73.8%) and 2 (25.9%). LMO development use purpose was implemented in various developmental uses: 51.3% in test and research use, 19% in health and medical use, and 12.9% in agriculture use. The experiment product, waste product, and products of host for LMO development were 327.2, 223.6, and 13.5 in number of plants; 280.6, 52.4, and 8.7 in number of animals; and $8.3\;{\times}\;10^{11}CFU$, $7.7\;{\times}\;10^{11}CFU$, and $6.5\;{\times}\;10^{11}CFU$ in microbes in 2004. The survey results about how to possess the LMO were very unreliable, because only 10.6% of the researchers returned the questionnaires. Consequently, we strongly suggest the scientific organizations as well as scientists should have more interests in biosafety of LMO research and an LMO biosafety management system should be developed for Korea's future biotechnology.

Impact of Complex Hemodynamics to the Management of ArterioVenous(AV) Fistula (동정맥루의 복합성 혈류학 소견이 그 관리에 미치는 영향)

  • Lee Byung-Boons
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.9-10
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    • 2002
  • Human circulatory system between heart and tissue is not directly connected in normal condition but mandatory to go through the capillary system in order to fulfill its physiologic aim to deliver oxygen and nutrients, etc. to the tissue and retrieve used blood together with waste products from the tissue properly. When abnormal connection between arterial and venous system (AV fistula), these two circulatory systems respond differently to the hemodynamic impact of this abnormal connection between high pressure (artery) and low pressure (vein) system. Depending upon the location and/or degree (e.g. size and flow) of fistulous condition, each circulatory system exerts different compensatory hemodynamic response to this newly developed abnormal inter-relationship between two systems in order to minimize its hemodynamic impact to own system of different hemodynamic characteristics. Pump action of the heart can assist the failing arterial system directly to maintain arterial circulation against newly established low peripheral resistance by the AV fistula during the compensation period, while it affects venous system in negative way with increased venous loading. However, the negative impact of increased heart action to the venous system is partly compensated by the lymphatic system which is the third circulatory system to assist venous system independently with different hemodynamics. The lymphatic system with own unique Iymphodynamics based on peristaltic circulation from low resistance to high resistance condition, also increases its circulation to assist the compensation of overloaded venous system. Once these compensation mechanisms should fail to fight to newly established hemodynamic condition due to this abnormal AV connection, each system start to show different physiologic ${\underline{de}compensation}$ including heart and lymphatic system. The vicious cycle of decompensation between arterial and vein, two circulatory system affecting each other by mutually negative way steadily progresses to show series of hemodynamic change throughout entire circulation system altogether including heart. Clinical outcome of AV fistula from the compensated status to decompensated status is closely affected by various biological and mechanical factors to make the hemodynmic status more complicated. Proper understanding of these crucial biomechanical factors iii particular on hemodyanmic point of view is mandatory for the advanced assessment of biomechanical impact of AV fistula, since this new advanced concept of AY fistula based on blomechanical information will be able to improve clinical control of the complicated AV fistula, either congenital or acquired.

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Effect of Organic Acids Fermented from the Settled Sludge and Animal Organic Wastes on the Denitrification (침전 슬러지와 가축분의 유기산화 및 발효유기산이 탈질반응에 미치는 영향)

  • Weon, Seung-Yeon;Park, Seung-Kook;Min, Kyung-Kook;Chung, Keun-Yook;Jun, Byong-Hee;Lee, Sang-Ill
    • Journal of Korean Society on Water Environment
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    • v.21 no.2
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    • pp.147-152
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    • 2005
  • Fermentation efficiencies of organic wastes from the variety of sources were evaluated based on the production of total volatile acids(TVA) in batch reactor. Mixing and pH were not significant factors in producing TVA from the organic wastes. After a 10-day fermentation, final TVA concentrations in piggery, cattle, poultry, and primary settled sludge of domestic wastewater were 8,900, 2,900, 7,370 and 1,630 mg/L, respectively. The pH of organic wastes was decreased from neutral to 5.7. The ratio of TVA to $NH_4{^+}-N$ produced from the animal waste ranged from 11.5 to 30.1, whereas, that in the primary settled sludge of domestic wastewater, was 5.4. Possibility of fermented organic wastes as the electron donors for denitrification in the activated sludge was investigated. In both acclimated and nonacclimated activated sludge, higher denitrification rates were obtained with fermented piggery sludge added than with either methanol or acetate added. The fermented organic acids derived from the primary settled sludge gave the higher denitrification rate ($4.2mg\;NO_3-N/g\;vss{\cdot}hr$) in the acclimated activated sludge. Denitrification rate was $1.5mg\;NO_3-N/g\;vss{\cdot}hr$ in the nonacclimated sludge with the fermented acids from the primary settled sludge of domestic wastewater added.

An Investigation for Air Pollutants Emitted from Small-Scale Incinerators in Highway Service Area (고속도로 휴게소의 소형소각로에서 배출되는 대기오염물질 조사)

  • Jang, Young-Kee;Choi, Sang-Jin;Kim, Kwan;Hong, Min-Sun;Choi, Join-In;Moon, Su-Ho;Kim, Soon-Tae;Kim, Seung-Do
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.6
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    • pp.539-546
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    • 2002
  • The physicochemical properties of solid wastes generated from seven highway service areas, four branch offices, and one construction site were analyzed in concert with air pollutants including heavy metals emitted from near-by small-scale incinerators. The amount of solid wastes generated from highway areas has been increasing with recent increases in the number of highways and passengers. Twelve incinerators examined in this study generally had capacity smaller than 100 kg/hr, most of which were equipped with cyclone for dust removal. It was seen that the concentrations of the gas-phase air pollutants (e.g., SO$_2$, NO$_{x}$, HCl and H$_2$S) were above the acceptable emission standards except one or two sites. CO concentrations at all incinerators were also higher due to incomplete combustion. In addition, particulate matters showed concentration six times higher at their maximum. The results of heavy metal analysis showed that the concentrations of Cu, Cd, and Ni satisfied the emission standards. whereas Pb at one site and Zn at five sites exceeded the standards. Cr measurement results indicated that 9 of 12 incinerators had higher values than the standard; especially one branch office showed nine times higher than normal concentration. In order to satisfy more stringent emission standards in the near future, it is necessary to install air pollution control system and to develop an intensified management plan.n.

Spatial Patterns of Methane Oxidation and Methanotrophic Diversity in Landfill Cover Soils of Southern China

  • Chi, Zi-Fang;Lu, Wen-Jing;Wang, Hong-Tao
    • Journal of Microbiology and Biotechnology
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    • v.25 no.4
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    • pp.423-430
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    • 2015
  • Aerobic CH4 oxidation is an important CH4 sink in landfills. To investigate the distribution and community diversity of methanotrophs and link with soil characteristics and operational parameters (e.g., concentrations of O2, CH4), cover soil samples were collected at different locations and depths from the Mengzi semi-aerobic landfill (SAL) in Yunnan Province of southern China. Specific PCR followed by denaturing gradient gel electrophoresis and realtime PCR were used to examine methanotrophs in the landfill cover soils. The results showed that different locations did harbor distinct methanotroph communities. Methanotrophs were more abundant in areas near the venting pipes because of the higher O2 concentrations. The depth of 20-25 cm, where the ratio of the CH4 to O2 was within the range from 1.3 to 8.6, was more conducive to the growth of CH4-oxidizing bacteria. Type II methanotrophs dominated in all samples compared with Type I methanotrophs, as evidenced by the high ratio of Type II to Type I methanotrophic copy numbers (from 1.76 to 11.60). The total copy numbers of methanotrophs detected were similar to other ecosystems, although the CH4 concentration was much higher in SAL cover soil. Methylobacter and Methylocystis were the most abundant Type I and Type II methanotrophs genera, respectively, in the Mengzi SAL. The results suggested that SALs could provide a special environment with both high concentrations of CH4 and O2 for methanotrophs, especially around the vertical venting pipes.

System dynamics simulation of the thermal dynamic processes in nuclear power plants

  • El-Sefy, Mohamed;Ezzeldin, Mohamed;El-Dakhakhni, Wael;Wiebe, Lydell;Nagasaki, Shinya
    • Nuclear Engineering and Technology
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    • v.51 no.6
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    • pp.1540-1553
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    • 2019
  • A nuclear power plant (NPP) is a highly complex system-of-systems as manifested through its internal systems interdependence. The negative impact of such interdependence was demonstrated through the 2011 Fukushima Daiichi nuclear disaster. As such, there is a critical need for new strategies to overcome the limitations of current risk assessment techniques (e.g. the use of static event and fault tree schemes), particularly through simulation of the nonlinear dynamic feedback mechanisms between the different NPP systems/components. As the first and key step towards developing an integrated NPP dynamic probabilistic risk assessment platform that can account for such feedback mechanisms, the current study adopts a system dynamics simulation approach to model the thermal dynamic processes in: the reactor core; the secondary coolant system; and the pressurized water reactor. The reactor core and secondary coolant system parameters used to develop system dynamics models are based on those of the Palo Verde Nuclear Generating Station. These three system dynamics models are subsequently validated, using results from published work, under different system perturbations including the change in reactivity, the steam valve coefficient, the primary coolant flow, and others. Moving forward, the developed system dynamics models can be integrated with other interacting processes within a NPP to form the basis of a dynamic system-level (systemic) risk assessment tool.

Comparative Assessment of Good Agricultural Practices Standards in Agricultural Product Quality Control Act with respect to Produce Safety Rule in Food Safety Modernization Act (식품안전현대화법의 농산물안전규칙과 농산물품질관리법의 농산물우수관리기준 비교평가)

  • Yoon, Deok-Hoon
    • Journal of Food Hygiene and Safety
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    • v.33 no.1
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    • pp.12-22
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    • 2018
  • The US government has enacted the Food Safety Modernization Act (FSMA) in 2011, which is being phased in and planned. The final Rules of Produce Safety focus on biological hazards related to agricultural production, harvesting, packaging and storage, which are being phased in since 2017 depending on farm scale. As a result of comparison with the Korean-GAP (Good Agricultural Practices) standards, it is difficult to compare the two standards to be compared with each other by 1:1. However, many of the Korean-GAP standards are similar to FSMA Produce Safety rules. However, the Korean-GAP standards can be judged differently according to the evaluator as a comprehensive standard, so the details of the standards need to be reinforced. In terms of the provisions, the Korean-GAP standards are the most appropriate for the safety of workers (FSMA Subpart D), followed by livestock and wild animals (FSMA Subpart I), buildings, equipment and tools (FSMA Subpart L) and harvesting activities (FSMA Sub-part K). However, there are some weaknesses in the field of agricultural water management (FSMA Subpart E) and farm manager's qualifications and training (FSMA Subpart C), and the response to the biological soil amendments of animal origin and human waste (FSMA Subpart F) is weak. The FSMA regulation is not a certification standard, but it is expected that the marbling effect, which is the standard laid down by the United States leading the world food safety standards, is expected to be considerable. Therefore, we hope that the review of the Korean-GAP standards will help improve the quality of agricultural products and expand our exports, since the standard for responding to microbiological safety emphasized in the FSMA regulations is the Korean-GAP standard.

The Present and the Future of Biogas Purification and Upgrading Technologies (바이오가스 정제 및 고질화 기술 현황 및 전망)

  • Heo, Namhyo;Park, Jaekyu;Kim, Kidong;Oh, Youngsam;Cho, Byounghak
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.172-172
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    • 2011
  • Anaerobic digestion(AD) has successfully been used for many applications that have conclusively demonstrated its ability to recycle biogenic wastes. AD has been successfully applied in industrial waste water treatment, stabilsation of sewage sludge, landfill management and recycling of biowaste and agricultural wastes as manure, energy crops. During AD, i.e. organic materials are decomposed by anaerobic forming bacteria and fina1ly converted to excellent fertilizer and biogas which is primarily composed of methane(CH4) and carbon dioxide(CO2) with smaller amounts of hydrogen sulfide(H2S) and ammonia(NH3), trace gases such as hydrogen(H2), nitrogen(N2), carbon monoxide(CO), oxygen(O2) and contain dust particles and siloxanes. The production and utilisation of biogas has several environmental advantages such as i)a renewable energy source, ii)reduction the release of methane to the atomsphere, iii)use as a substitute for fossil fuels. In utilisation of biogas, most of biogas produced from small scale plant e.g. farm-scale AD plant are used to provide as energy source for cooking and lighting, in most of the industrialised countries for energy recovery, environmental and safety reasons are used in combined heat and power(CHP) engines or as a supplement to natural. In particular, biogas to use as vehicle fuel or for grid injection there different biogas treatment steps are necessary, it is important to have a high energy content in biogas with biogas purification and upgrading. The energy content of biogas is in direct proportion to the methane content and by removing trace gases and carbon dioxide in the purification and upgrading process the energy content of biogas in increased. The process of purification and upgrading biogas generates new possibilities for its use since it can then replace natural gas, which is used extensively in many countries, However, those technologies add to the costs of biogas production. It is important to have an optimized purification and upgrading process in terms of low energy consumption and high efficiency giving high methane content in the upgraded gas. A number of technologies for purification and upgrading of biogas have been developed to use as a vehicle fuel or grid injection during the passed twenty years, and several technologies exist today and they are continually being improved. The biomethane which is produced from the purification and the upgrading process of biogas has gained increased attention due to rising oil and natural gas prices and increasing targets for renewable fuel quotes in many countries. New plants are continually being built and the number of biomethane plants was around 100 in 2009.

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A Political Proposal for the Reverse Logistics Activation (역물류 활성화를 위한 정책적 제언)

  • Sun, Il-Suck
    • Journal of Distribution Research
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    • v.15 no.5
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    • pp.61-79
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    • 2010
  • As the interest and the importance of environmental protection increases rapidly, the environment considers to be not only the item that requires a control and a duty fundamental element but the fundamental element to enhance the internection icompetitiveness n so. Along with the collapse of the foreign trade barrier and the quality improvement of a customer's life qu life of a an object is shortened liforder to sectsfy the customer's lemands and as the result of it quaother critical issues rmparding the waste treatment and recasles are now thought to be momentou onlyaddition to the issue of the greenhou e gases reduction that is considered as one of me q issues among many internection ienvironmental issues. To keep up the pace with the environmental flow qube notd countries have nlreal iput their attempts to solve this environmental problems through a number of rmpulactios and acctios and they have showed a great concern for it as it is an internection iproblem that they should aasroaeronlythe aspect of not just a compan isr a country but of the wte e globn ivillage. Sueroenvironmental flow alemaned the logistic stratmpy of a compan iand it brought up the demand for the reverse logistics in a supply chain. For the reason above, the concept of reverse logistics and classification, the comparison with any similar concepts and its necessity are studied in this research through the theoretical consideration and the current state of the reverse logistics is organized in this research by acknowledging the domestic development process and the properties regarding the recycles of resources. In addition, the way to apply to the nation was investigated by comparing with the environmentalism development process, the reverse logistics policies and examples of advanced countries in logistics. The research proposed building of intimate cooperative system between a shipper and logistic service provider for the reverse logistics throughout the whole supply chain, the financial support, amendment of regulations, support Eco-friendly logistic technology development and the propagation, effective logistic system development and others and it is expected to bring a significant meaning to the reverse logistic policy and operation later on.

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Dynamic Characteristics of Liquidity Filling Materials Mixed with Reclaimed Ash (매립석탄회를 혼합한 유동성 충진재의 동적거동특성)

  • Chae, Deokho;Kim, Kyoungo;Shin, Hyunyoung;Cho, Wanjei
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.4
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    • pp.5-11
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    • 2014
  • Recently, there have been various lifeline installations constructed in the underground space of urban area due to the effective use of land. For newly installed lifelines or the management of the installed lifelines, many construction activities of excavation and backfilling are observed. Around these area, there are possibilities of collapse or excessive settlement due to the leaking of the pipe or unsatisfactory compaction of backfill material. Besides, construction costs can be saved since the on-site soils are used. The application of this liquidity filling material is not only to the lifeline installation but also to underpin the foundation under the vibrating machinery. On the evaluation of the applicability of this method to this circumstance, the strength should be investigated against the static load from the machine load as well as the vibration load from the activation of the machine. In this study, the applicability of the liquidity fill material on the foundation under the vibrating machinery is assessed via uniaxial compression and resonant column tests. The liquidity filling material consisting of the on-site soils with loess and kaolinite are tested to investigate the static and dynamic characteristics. Furthermore, the applicability of the reclaimed ash categorized as an industrial waste is evaluated for the recycle of the waste to the construction materials. The experimental results show that the shear modulus and 7 day uniaxial strength of the liquidity filling material mixed with reclaimed ash show higher than those with the on-site soils. However, the damping ratio does not show any tendency on the mixed materials.