• Title/Summary/Keyword: Various Contamination

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Overview of Coffee Waste and Utilization for Biomass Energy Production in Vietnam

  • Thriveni, Thenepalli;Kim, Minsuk;Whan, Ahn Ji
    • Journal of Energy Engineering
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    • v.26 no.1
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    • pp.76-83
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    • 2017
  • In this paper, the carbon resources recycling of the overview of coffee waste generation in Vietnam. Since few years, there has been a significant research studies was done in the areas of coffee waste generation areas and also waste water generation from coffee production. The coffee residue (solid) and waste water (liquid) both are caused the underground water contamination and also soil contamination. These residues contain high organic matter and acid content leads to the severe threat to environment. In second stage of coffee production process, the major solid residue was generated. Various solid residues such as spent coffee grounds, defective coffee beans and coffee husks) pose several environmental concerns and specific problems associated with each type of residue. Due to the unlimited usage of coffee, the waste generation is high. At the same time, some researchers have been investigated the spent coffee wastes are the valuable sources for various valuable compounds. Biodiesel or biomass productions from coffee waste residues are the best available utilization method for preventing the landfill problems of coffee waste residues.

A study on the classification of various defects in concrete based on transfer learning (전이학습 기반 콘크리트의 다양한 결함 분류에 관한 연구)

  • Younggeun Yoon;Taekeun Oh
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.2
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    • pp.569-574
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    • 2023
  • For maintenance of concrete structures, it is necessary to identify and maintain various defects. With the current method, there are problems with efficiency, safety, and reliability when inspecting large-scale social infrastructure, so it is necessary to introduce a new inspection method. Recently, with the development of deep learning technology for images, concrete defect classification research is being actively conducted. However, studies on contamination and spalling other than cracks are limited. In this study, a variety of concrete defect type classification models were developed through transfer learning on a pre-learned deep learning model, factors that reduce accuracy were derived, and future development directions were presented. This is expected to be highly utilized in the field of concrete maintenance in the future.

Survey for contamination and study for reduction of ochratoxin A and aflatoxin in red pepper (고추 중 오크라톡신 A와 아플라톡신의 오염도 조사 및 저감화방안 연구)

  • Kim, Dong-Ho;Jang, Han-Sub;Kim, Yeong-Min;Ahn, Jong-Sung
    • Journal of Food Hygiene and Safety
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    • v.24 no.4
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    • pp.299-306
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    • 2009
  • Aflatoxin (AF) and Ochratoxin A (OTA) are carcinogenic and possible carcinogenic mycotoxins respectively produced by Aspergillus spp or Penicillium spp. The study for contamination survey and proposal for reduction of mycotoxin in red pepper were carried out. 192 samples were collected at such various stages and markets as pre/post-harvest stages, internet shopping mall /super-market and small stakeholder mill/geographically indicated company. As only 2 samples were positive for aflatoxin, so contamination rate was 1.04%. In the meanwhile, contamination rate for ochratoxin A was 21.88% and a various amount of OTA was detected in 42 positive samples. 6 samples were found to be contaminated at higher level than $5\;{\mu}gkg^{-1}$ for ochratoxin A, which was established recently as a maximum permissible limit in korea. There was no difference in degree of contamination with regard to cultivation type because any mycotoxin was not found at all in both organically and conventionally grown red pepper. But, there was statistically significant difference in the process of manufacturing. Finished products were OTA-contaminated at a level of $2.32\;{\pm}\;6.54\;{\mu}gkg^{-1}$(mean ${\pm}$ SD), even though OTA was not detected in deep frozen red peppers right after long term storage. And contamination for OTA was a level of $0.33\;{\pm}\;0.91\;{\mu}gkg^{-1}$(mean ${\pm}$ SD) in red paprika powder after uv sterilization, while the contamination for OTA was $2.78\;{\pm}\;4.49\;{\mu}kg^{-1}$(mean ${\pm}$ SD) in non-uv sterilized powder. In addition, our investigation shows that higher OTA contamination occurred in some of famous brand products sold in super-market and domestic products than products collected through on-line shopping or from small stakeholder mills and imported products respectively, however, difference was not statistically significant.

Construction of the evaluating facilities against contamination characteristic for power installation (전력설비에 대한 내오손특성 평가설비 구축)

  • Lee, J.G.;Kim, M.K.;Jeong, J.Y.;Kim, I.S.;Moon, I.W.;Kang, Y.S.;Sung, M.J.
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.1851-1853
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    • 2004
  • The important consideration in laboratory designing and construction of the artificial pollution testing facilities including 300kV, 1800kVA AC test system, which enable to test and evaluate the UHV dielectric performance of power insulators up to transmission class, has been dealt in this paper. To evaluate the performance characteristics against contamination for various power installation, especially for the insulators and kinds of bushings, brief investigation and an analysis of test objects and related international codes and standards have been conducted. With the special consideration concerning other matters in designing of these testing facilities have been described with the fixed ratings and references.

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Effect of Gamma Irradiation on the Microbial Safety and Biological Activities of Tuna Cooking Juices (감마선 조사에 따른 참치 자숙액의 위생화 및 기능성 변화 연구)

  • Byun, Myung-Woo
    • KSBB Journal
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    • v.27 no.4
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    • pp.222-226
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    • 2012
  • In this study, the effect of gamma irradiation on the microbial contamination and biological activities of tuna cooking juices was investigated. Tuna cooking juice was by-produced during the canning processing, and had various functional components. But, it was shown that the tuna cooking juice was seriously contaminated. Gamma irradiation effectively reduced the microbial population in tuna cooking juice. Also, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, tyrosinse inhibitory activity, and ACE inhibitory activity of tuna cooking juices were all increased as a result of gamma irradiation. These results suggest that wasted tuna cooking juices can be used as a functional component in the food and cosmetic industries if the irradiation technology were applied.

A Comparison Study of Survival Regression Models Based on Data Depths (뎁스를 이용한 생존회귀모형들의 비교연구)

  • Kim, Jee-Yun;Hwang, Jin-Soo
    • The Korean Journal of Applied Statistics
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    • v.20 no.2
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    • pp.313-322
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    • 2007
  • Several robust censored depth regression methods are compared under contamination. Park and Hwang(2003) suggested a way to circumvent the censoring issue by incorporating Kaplan-Meier type weight in halfspace regression depth and Park(2003) used a similar technique to simplicial regression depth. Hubert et al. (2001) suggested a high breakdown point regression depth based on projection called rcent. A new method to implement censoring in rcent is suggested and compared with two precedents under various contamination and censoring schemes.

Hygienic Aspects of Campylobacter Enteritis (Campylobacter장염에 의한 식품위생학적인 고찰)

  • 이용욱;홍종해
    • Journal of Food Hygiene and Safety
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    • v.1 no.1
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    • pp.57-66
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    • 1986
  • Campylobacter jejuni has been recognized as one of the causes of human gastroenteritis. The feces of a variety of reservoir animals contain c. jejuni as commensals in the intestinal tracts, and are fundamental source of contamination. The intestinal organisms contaminate carcasses, equipment tools hands of the processing line workers and air of the processing facility. Once the contamination happens in the slaughterhouses or the meat processing facilities, it is very difficult to keep the carcasses free from the infection of c. jejuni. Various disinfectants are effective in minimizing the number of Campylobacter infections in the processing facilities by washing contaminated carcasses, tools, and hands. Direct contact with infected animals has been incriminated in transmission of infection caused by C. jejuni. Freezing, cooling with dry air and gamma irradiation are an effective way for preserving the meat and eliminating the transmission, but broad and enforced studies are needed for the practical use.

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Melamine testing of meat, eggs and diary products sold in Incheon

  • Ra, Do-Kyung;Hong, Seong-Hee;Lee, Jeong-Gu;Lee, Sung-Mo
    • Korean Journal of Veterinary Service
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    • v.32 no.4
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    • pp.381-383
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    • 2009
  • From Oct. 2008 to Oct. 2009, 619 livestock products sold in Incheon were examined for melamine contamination. HPLC was used to detect the melamine concentration from various products. $C_{18}$ column $(3.9\times150mm,\;4{\mu}m)$ was applied with a phase composed of 10mM citric acid and 10mM sodium octane sulfonate : acetonitrile (in ratio 90:10) pumped isocratically at 1.0ml/min. Melamine was not detected from any of the products at the level of LOD 0.03mg/kg and LOQ 0.08mg/kg, suggesting that no melamine contamination was ascertained in livestock products in Incheon area. However, further tests should be done to detect other melamine analogues for the evaluation of toxicity and safety of melamine and cyanuric acid in the future.

An Experimental Study on the Measurement of Soot Contamination in a Diesel Engine Oil (디젤 엔진오일 내 Soot 함량 증가에 따른 오염도 측정에 관한 실험적 고찰)

  • 공호성;조성용;윤의성;한흥구;정동윤
    • Tribology and Lubricants
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    • v.19 no.5
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    • pp.251-258
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    • 2003
  • New method and device for the on-line measurement of soot concentration in a diesel engine oil are proposed, where the measurement principle is based mainly on attenuated internal total reflection. The detector were evaluated in various ranges of contaminated oils by carbon black particles. It was found that the proposed detector could be well used to monitor the oil deterioration due to soot contamination. Operational range of the detector was found from 0 to 5 mass percentage of soot content. Test results with water and fuel dilution showed that these effects were not remarkable. However, adsorption of carbon black particles onto the measurement surface was considered to be a critical problem of the detector. Effects of particle deposition on the interface was experimentally evaluated with the oil temperature and flow turbulence and discussed throughout this work.

Numerical Investigation of Contamination Particle's Trajectory in a Head/slider Disk Interface (헤드/디스크 인터페이스 내에서 오염 입자의 거동에 관한 수치적 연구)

  • Park, Hee-Sung;Hwang, Jung-Ho;Choa, Sung-Hoon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.3
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    • pp.477-484
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    • 2000
  • Microcontamination caused by particle deposition on the head disk interface threatens the reliability of hard disk drive. Design of slider rail to control contamination becomes an important issue in magnetic recording. In this paper, how particles adhere to the slider and the disk is examined. To investigate accumulation mechanism of the particles, trajectory of the particles in a slider/disk interface is simulated with considering various forces including drag force, gravitational force, Saffman lift force, and electrostatic force. It is found that the charged particles can easily adhere to the slider or disk surface, if an electric field exists between the slider and the disk. It is supposed that the vertical motion of the particles should be related with not only Saffman force but also electrostatic force.