• 제목/요약/키워드: Tolerance limits

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잔류기준 설정을 위한 식품원료의 분류 및 명칭 (Classification and Nomenclature of Raw Food Materials for Tolerance Setting of Chemical Residues and Contaminants)

  • 이서래
    • 한국환경농학회지
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    • 제19권3호
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    • pp.259-269
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    • 2000
  • 식품원료인 농수축산물은 생산측면과 소비측면에서 각각 관행적으로 분류되어 사용되어 왔다. 한편 식품원료 중 잔류농약, 가축의약품, 환경오염물질과 같은 화학잔류물의 기준설정 및 규제를 위해서는 잔류가능성을 감안한 분류방식이 요구되고 있으나 식품원료의 분류방식이 통일되지 못하여 많은 혼란을 가져왔다. 본 연구에서는 농산물 중 농약잔류 허용기준을 적용하는데 있어서 국내외적으로 나타난 문제들을 지적하였으며 국제식품규격위원회의 Codex 기준을 무난히 수용할 수 있는 농수축산물 분류방식을 제시하였다. 이와 아울러 여기에서 제시한 분류법을 이용하여 잔류농약을 비롯한 다른 화학물질의 오염기준을 설치할 경우의 고려할 점을 제시하였다.

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화학반응 공정에서의 공정조건 및 허용차설계 (Parameter and Tolerance Designs of the Chemical Reaction Process)

  • 안종석;윤원영
    • 품질경영학회지
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    • 제30권1호
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    • pp.97-117
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    • 2002
  • We apply Taguchi method to the process optimization problem of chemical reaction process, and some case studies are done to find out the way for cost reduction and quality improvement The parameter and tolerance designs of Taguchi mettled are done with operation data of a chemical process and we propose a procedure how to use and analyze the operation data to find the optimal process conditions and tolerance limits. In order to use the continuous values in experiment conditions, it is suggested how to determine the interval of each level by discrete values and to treat any missing values caused from discrete 4 levels.

Mechanisms of immune tolerance to allergens in children

  • Kucuksezer, Umut C.;Ozdemir, Cevdet;Akdis, Mubeccel;Akdis, Cezmi A.
    • Clinical and Experimental Pediatrics
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    • 제56권12호
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    • pp.505-513
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    • 2013
  • Because the prevalence of allergic diseases has significantly increased in recent years, understanding the causes and mechanisms of these disorders is of high importance, and intense investigations are ongoing. Current knowledge pinpoints immune tolerance mechanisms as indispensable for healthy immune response to allergens in daily life. It is evident that development and maintenance of allergen-specific T cell tolerance is of vital importance for a healthy immune response to allergens. Such tolerance can be gained spontaneously by dose-dependent exposures to allergens in nature or by allergen-specific immunotherapy. Allergen-specific immunotherapy induces regulatory T cells with the capacity to secrete interleukin-10 and transforming growth factor-${\beta}$, limits activation of effector cells of allergic inflammation (such as mast cells and basophils), and switches antibody isotype from IgE to the noninflammatory type IgG4. Although allergen-specific immunotherapy is the only method of tolerance induction in allergic individuals, several factors, such as long duration of treatment, compliance problems, and life-threatening side effects, have limited widespread applicability of this immunomodulatory treatment. To overcome these limitations, current research focuses on the introduction of allergens in more efficient and safer ways. Defining the endotypes and phenotypes of allergic diseases might provide the ability to select ideal patients, and novel biomarkers might ensure new custom-tailored therapy modalities.

급격한 저염분 노출에 따른 참돔 Pagrus major 치어의 단기 행동반응 및 내성 한계에 관한 연구 (Short-term behavioral responses and tolerance limits of red seabream Pagrus major fingerlings following sudden low salinity exposure)

  • 윤성진
    • 환경생물
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    • 제39권4호
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    • pp.495-506
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    • 2021
  • In this study, using a continuous behavior measurement technique, the short-term behavioral responses and tolerance limits of red seabream Pagrus major fingerlings to sudden exposure to low salinity in a controlled environment were observed. The activity of the fingerlings suddenly exposed to 21.4, 17.3, and 9.8 psu increased temporarily at the initial exposure to show irregular swimming behavior, but then recovered a stable activity pattern through rapid salinity adaptation. However, the organisms suddenly exposed to 7.3 and 4.3 psu could not withstand the salinity stress, and their swimming behavior was severely disturbed and all individuals died within 48 hours. The findings suggest that red seabream underwent a temporary salinity stress process at the beginning of the exposure to concentrations of 10.0 psu or higher. At these concentrations, osmotic control was possible within at least 11 hours, so stable metabolic activity was also possible. However, organisms suddenly exposed to concentrations below 5.0 psu exceeded the tolerance to low salinity and the sublethal limit. In red seabream exposed to this concentration range, severe behavioral and metabolic disturbances were observed, and death was observed due to osmotic control failure. In conclusion, a salinity range of 5.0 to 10.0 psu can be predicted to correspond to a concentration range in which the osmotic control ability of the red seabream fingerlings is lost, and sub-lethal reactions occur.

Physicochemical tolerance ranges and ecological characteristics in two different populations of Carassius auratus and Cyprinus carpio

  • Kang, Seung Gu;Choi, Ji-Woong;An, Kwang-Guk
    • Journal of Ecology and Environment
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    • 제38권2호
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    • pp.195-211
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    • 2015
  • The objectives of this research were to determine mean and maximum tolerance ranges of Carassius auratus ($C_a$) and Cyprinus carpio ($C_c$) populations on various physico-chemical parameters and ecological indicator metrics. Little is known about chemical tolerance ranges of the two species, even though these species are widely distributed species in aquatic ecosystems. Maximum tolerance ranges of $C_a$-population to total nitrogen (TN) and total phosphorus (TP) were $20.3mgL^{-1}$ and $2.0mgL^{-1}$, respectively. Optimal ranges of TN and TP in the $C_a$-population were $1.7-5.0mgL^{-1}$ and $0.06-0.30mgL^{-1}$, respectively. Such nutrient regimes of the $C_a$-population were evaluated as hypereutrophy, indicating high tolerance limits. The $C_c$-population had similar ecological characteristics to $C_a$-population, but the mean tolerance ranges of TN, TP, BOD, and COD were significantly (p < 0.05) greater than the $C_a$-population. Ecological patterns of trophic composition and tolerance guilds in the $C_a$-population were similar to those of the $C_c$-population. The model value of Index of Biological Integrity (IBI) of the habitat where C. auratus and C. carpio co-occurred averaged $15.0{\pm}4.3$ and $12.9{\pm}3.6$, respectively. Based on the modified criteria of the United States Environmental Protection Agency (Klemm et al. 1993), it indicated poor ecological health of both species. These results suggest that both species are highly tolerant to chemical and physical habitat conditions of waterbodies, and that the chemical tolerance range of $C_c$-population was higher than $C_a$-population.

국제기구 및 외국에서 농산물중 농약잔류 허용기준의 설정절차 (Procedures in Establishing Residue Limits of Pesticides on Food Crops in Codex Alimentarius Commission and Foreign Countries)

  • 이미경;홍무기;박건상;최동미;임무혁;이서래
    • 한국환경농학회지
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    • 제24권1호
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    • pp.45-55
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    • 2005
  • This study was undertaken to find out necessary measures to improve the tolerance setting system of pesticide residues on food crops in Korea which is scientifically reasonable and harmonizable with international standards. Information on tolerance setting systems of pesticide residues by Codex Alimentarius Commission, Joint FAO/WHO Meeting of Experts on Pesticide Residues, USA, EU, Japan and Taiwan was collected and analyzed. On the basis of information in the above countries, necessary actions to be taken by the Korean regulatory authorities were recommended with respect to priority setting, maximum residue limits (MRLs) setting based on field residue data, group MRLs, minor crop problems, quantitation limit and dietary intake assessment.

Clinical and preclinical tolerance protocols for vascularized composite allograft transplantation

  • Yang, Jerry Huanda;Johnson, Ariel C.;Colakoglu, Salih;Huang, Christene A.;Mathes, David Woodbridge
    • Archives of Plastic Surgery
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    • 제48권6호
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    • pp.703-713
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    • 2021
  • The field of vascularized composite allografts (VCAs) has undergone significant advancement in recent decades, and VCAs are increasingly common and accepted in the clinical setting, bringing hope of functional recovery to patients with debilitating injuries. A major obstacle facing the widespread application of VCAs is the side effect profile associated with the current immunosuppressive regimen, which can cause a wide array of complications such as infection, malignancy, and even death. Significant concerns remain regarding whether the treatment outweighs the risk. The potential solution to this dilemma would be achieving VCA tolerance, which would allow recipients to receive allografts without significant immunosuppression and its sequelae. Promising tolerance protocols are being studied in kidney transplantation; four major trials have attempted to withdraw immunosuppressive treatment with various successes. The common theme in all four trials is the use of radiation treatment and donor cell transplantation. The knowledge gained from these trials can provide valuable insight into the development of a VCA tolerance protocol. Despite similarities, VCAs present additional barriers compared to kidney allografts regarding tolerance induction. VCA donors are likely to be deceased, which limits the time for significant pre-conditioning. VCA donors are also more likely to be human leukocyte antigen-mismatched, which means that tolerance must be induced across major immunological barriers. This review also explores adjunct therapies studied in large animal models that could be the missing element in establishing a safe and stable tolerance induction method.

정규분포 공정 가정하에서의 공정능력지수 $C_{pmk}$ 에 관한 효율적인 신뢰한계 (Better Confidence Limits for Process Capability Index $C_{pmk}$ under the assumption of Normal Process)

  • 조중재;박병선;박효일
    • 품질경영학회지
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    • 제32권4호
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    • pp.229-241
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    • 2004
  • Process capability index is used to determine whether a production process is capable of producing items within a specified tolerance. The index $C_{pmk}$ is the third generation process capability index. This index is more powerful than two useful indices $C_p$ and $C_{pk}$. Whether a process distribution is clearly normal or nonnormal, there may be some questions as to which any process index is valid or should even be calculated. As far as we know, yet there is no result for statistical inference with process capability index $C_{pmk}$. However, asymptotic method and bootstrap could be studied for good statistical inference. In this paper, we propose various bootstrap confidence limits for our process capability Index $C_{pmk}$. First, we derive bootstrap asymptotic distribution of plug-in estimator $C_{pmk}$ of our capability index $C_{pmk}$. And then we construct various bootstrap confidence limits of our capability index $C_{pmk}$ for more useful process capability analysis.

오차의 허용범위를 고려한 수동형 필터의 특성 해석 (Performance Analysis for Passive Filter Considering Allowable Limits of Tolerance)

  • 김종겸;김일증
    • 전기학회논문지P
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    • 제58권1호
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    • pp.38-43
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    • 2009
  • Reactors are connected with capacitors to passive filter circuits for reducing harmonics caused by power conversion application. This passive filter frequently gets out of order by voltage and current stress. Especially filter reactor has too much voltage harmonics components, its trouble rate is higher than capacitor. In this paper, we analyzed voltage and current of reactor and capacitor used for passive filter by simulation and measurement. If reactor has a tolerance on variation of reactance value, series resonance frequency is different from originally filter design frequency and parallel resonance can be generated at the close point of the former. Because filter absorbs harmonic component of non-linear load, much of harmonic voltage has been impacted on reactor.

Mechanical and electro-mechanical analysis in differently stabilized GdBCO coated conductor tapes with stainless steel substrate

  • Nisay, Arman R.;Shin, Hyung-Seop
    • 한국초전도ㆍ저온공학회논문지
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    • 제15권2호
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    • pp.29-33
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    • 2013
  • The understanding of the strain dependence of critical current, $I_c$, in the reversible region is important for the evaluation of the performance of coated conductor (CC) tapes in practical applications. In this study, the stress/strain tolerance of $I_c$ in GdBCO CC tapes with stainless steel substrate stabilized by additional Cu and brass laminate was analyzed quantitatively through $I_c$-strain measurement at 77 K under self-field. The variation in irreversible strain limits of CC tapes by the addition of stabilizing layers was analyzed through the consideration of the pre-strain induced on the GdBCO coating film. The results were then compared with the ones previously reported for GdBCO CC tapes with Hastelloy substrate. As a result, GdBCO CC tapes with stainless steel substrate showed much higher strain tolerance of $I_c$ as compared with those adopting Hastelloy substrate.