• 제목/요약/키워드: Tolerance factor

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ASME BPVC Section XI Appendix L의 결함허용평가에 따른 허용운전주기 민감도 분석 (Sensitivity Analysis for Allowable Operating Period Based on the Flaw Tolerance Evaluation of ASME BPVC Section XI Appendix L)

  • 오창식;조두호;정명조
    • 한국압력기기공학회 논문집
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    • 제17권2호
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    • pp.126-136
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    • 2021
  • During operation of nuclear power plants, the fatigue assessment should be conducted repeatedly, considering changes of operating environments. For the case that cumulative usage factors (CUFs) may exceed the acceptance limit, flaw tolerance evaluation can be an alternative method to meet the regulatory requirements. In this respect, this paper analyzes the effects of the input variables for flaw tolerance evaluation based on ASME BPVC Section XI Appendix L. The reference analysis is performed for the example problem in NUREG/CR-6934. Then effects of the crack orientation, stress intensity factor solutions, thermal stress profiles, fatigue stress decomposition and fatigue crack growth curves are considered for the sensitivity analysis. The results show that the stress analysis considering the actual environment plays a crucial role in flaw tolerance evaluation.

K-척도와 인터넷 사용 내성정도를 이용한 인터넷 중독 진단 방법의 비교 연구 (Comparative study of K-scale and the internet addiction diagnosis method using tolerance degree for internet use)

  • 김희재;김종완
    • 컴퓨터교육학회논문지
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    • 제15권2호
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    • pp.47-55
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    • 2012
  • 한국정보화진흥원에서 개발한 4가지 부류의 20문항으로 구성된 한국형 성인 인터넷 중독 자가진단 척도 (K-척도)의 4가지 요인 가운데 '내성 및 몰입 요인'이 인터넷 중독 진단에 가장 큰 영향을 주는 요인임을 데이터마이닝 기법으로 밝힌다. 본 연구에서는 이를 토대로 사용자의 직무 무관 인터넷 이용 활동에 대한 내성정도를 이용하여 인터넷 중독 진단을 수행하는 새로운 방법을 제시한다. K-척도와 제안된 내성정도를 이용한 인터넷 중독 진단 방법에 대하여 설문조사에 참여한 일부 사용자 대상으로 피드백을 받은 결과, 제안된 사용자 중심의 진단 방식이 사용자 고의에 의한 미발견 중독자 발견에 효과가 있음을 확인하였다.

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Service Deployment Strategy for Customer Experience and Cost Optimization under Hybrid Network Computing Environment

  • Ning Wang;Huiqing Wang;Xiaoting Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제17권11호
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    • pp.3030-3049
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    • 2023
  • With the development and wide application of hybrid network computing modes like cloud computing, edge computing and fog computing, the customer service requests and the collaborative optimization of various computing resources face huge challenges. Considering the characteristics of network environment resources, the optimized deployment of service resources is a feasible solution. So, in this paper, the optimal goals for deploying service resources are customer experience and service cost. The focus is on the system impact of deploying services on load, fault tolerance, service cost, and quality of service (QoS). Therefore, the alternate node filtering algorithm (ANF) and the adjustment factor of cost matrix are proposed in this paper to enhance the system service performance without changing the minimum total service cost, and corresponding theoretical proof has been provided. In addition, for improving the fault tolerance of system, the alternate node preference factor and algorithm (ANP) are presented, which can effectively reduce the probability of data copy loss, based on which an improved cost-efficient replica deployment strategy named ICERD is given. Finally, by simulating the random occurrence of cloud node failures in the experiments and comparing the ICERD strategy with representative strategies, it has been validated that the ICERD strategy proposed in this paper not only effectively reduces customer access latency, meets customers' QoS requests, and improves system service quality, but also maintains the load balancing of the entire system, reduces service cost, enhances system fault tolerance, which further confirm the effectiveness and reliability of the ICERD strategy.

Alteration of macronutrients, metal translocation and bioaccumulation as potential indicators of nickel tolerance in three Vigna species

  • Ishtiaq, Shabnam;Mahmood, Seema;Athar, Mohammad
    • Advances in environmental research
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    • 제3권1호
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    • pp.71-86
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    • 2014
  • Macronutrients ($Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$), yield and yield components, bioaccumulation and translocation of metal in plant parts of three Vigna species (V. cylindrica, V. mungo, V. radiata) were evaluated at 0, 50, 100 and $150mgkg^{-1}$ soil of Nickel (Ni). A marked inhibition (p < 0.001) in the distribution of various macronutrients was noticed in these Vigna species except for $Mg^{2+}$ content of the shoot and leaves. Similarly, all species retained more $Ca^{2+}$ in their roots (p < 0.05) as compared to the aerial tissues. Ni induced a drastic decline (p < 0.001) for various yield and yield attributes except for 100 seed weight. Toxicity and accumulation of Ni in plant tissues considerably increased in a concentration dependent manner. Vigna species signify an exclusion approach for Ni tolerance as both bioaccumulation factor (BF) and translocation factor (TF) were less than 1.0. The Ni content of plants being root > shoot > leaves > seeds. Scoring for percentage stimulation and inhibition (respective to control) at varying levels of Ni revealed tolerance of the species in an order of V. radiata > V. cylindrica > V. mungo. The acquisition of Ni tolerance in V. radiata seems to occur through an integrated mechanism of metal tolerance that includes sustainable macronutrients uptake, stronger roots due to greater deposition of $Ca^{2+}$in the roots, restricted transfer of Ni to above ground tissues and seeds as well as exclusion capacity of the roots to bind appreciable amount of metal to them. Thus, metal tolerant potential of V. radiata could be of great significance to remediate metal contaminated soil owing lesser impact of Ni on macro-nutrients, hence the yield.

Application of the Combination of Soybean Lecithin and Whey Protein Concentrate 80 to Improve the Bile Salt and Acid Tolerance of Probiotics

  • Gou, Xuelei;Zhang, Libo;Zhao, Shiwei;Ma, Wanping;Yang, Zibiao
    • Journal of Microbiology and Biotechnology
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    • 제31권6호
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    • pp.840-846
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    • 2021
  • To improve the bile salt and acid tolerance of probiotics against gastrointestinal stresses, we investigated the effects of soybean lecithin and whey protein concentrate (WPC) 80 on the bile salt tolerance of Lacticaseibacillus paracasei L9 using a single-factor methodology, which was optimized using response surface methodology (RSM). The survival rate of L. paracasei L9 treated with 0.3% (w/v) bile salt for 2.5 h, and combined with soybean lecithin or WPC 80, was lower than 1%. After optimization, the survival rate of L. paracasei L9 incubated in 0.3% bile salt for 2.5 h reached 52.5% at a ratio of 0.74% soybean lecithin and 2.54% WPC 80. Moreover, this optimized method improved the survival rate of L. paracasei L9 in low pH condition and can be applied to other lactic acid bacteria (LAB) strains. Conclusively, the combination of soybean lecithin and WPC 80 significantly improved the bile salt and acid tolerance of LAB. Our study provides a novel approach for enhancing the gastrointestinal tolerance of LAB by combining food-derived components that have different properties.

한국형 안경조제의 광학적 허용오차 설정 (The Optical Tolerances' Decision of the Ophthalmic Dispensing for Korean Models)

  • 김용근
    • 한국안광학회지
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    • 제3권1호
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    • pp.189-199
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    • 1998
  • 완성안경의 광학적 허용요차에 대한 system을 안경처방서 작성시 환경, 주시거리, 하방 주시각, 테의 늘어남, 정정간 거리(VD), 토릭렌즈의 축, 렌즈의 기울기 등의 누적 오차 합 형태로 만들었다. 굴절력(D)에 따른 $O{\cdot}C$의 허용치 크기(T) 관계를 $T=T_0e^{-aD}$으로 주어지고 여기서, $T_0$는 굴절력이 0인 평면렌즈의 허용치 크기이고, ${\alpha}$는 허용치 factor이다. RAL-915에 대응하는 새로운 형태의 허용오차를 적용하는 경우, 허용오차가 큰 방향에 대해서는 허용치 factor ${\alpha}$$0.166(T_0=5.90)$이고, 허용오차가 작은 방향에 대해서는 허용치 factor ${\alpha}$$0.166(T_0=2.95)$ 값을 갖는다.

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Roc10, a Rice HD-Zip transcription factor gene, modulates lignin biosynthesis for drought tolerance

  • Bang, Seung Woon;Lee, Dong-Keun;Jung, Harin;Chung, Pil Joong;Kim, Youn Shic;Choi, Yang Do;Suh, Joo-Won;Kim, Ju-Kon
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.159-159
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    • 2017
  • Drought, a common environmental constraint, induces a range of physiological, biochemical and molecular changes in plants, and can cause severe reductions in crop yield. Consequently, understanding the molecular mechanisms of drought tolerance is an important step towards crop biotechnology. Here, we report that the rice (Oryza sativa) homeodomain-leucine zipper class IV transcription factor gene, ${\underline{R}ice}$ ${\underline{o}utermost}$ ${\underline{c}ell-specific}$ gene 10 (Roc10), enhances drought tolerance and grain yield by increasing lignin accumulation in ground tissues. Overexpression of Roc10 in rice significantly increased drought tolerance at the vegetative stages of growth and promoted both more effective photosynthesis and a reduction in water loss rate, compared with non-transgenic controls or RNAi transgenic plants. Importantly, Roc10 overexpressing plants had a higher drought tolerance at the reproductive stage of growth and a higher grain yield compared with the controls under field-drought conditions. Roc10 is mainly expressed in outer cell layers including the epidermis and the vasculature of the shoots, which coincides with areas of cell wall lignification. Roc10 overexpression elevated the expression levels of lignin biosynthetic genes in shoots, with a concomitant increase in the accumulation of lignin, while the overexpression and RNAi lines showed opposite patterns of lignin accumulation. We identified downstream target genes of Roc10 by performing RNA-seq and chromatin immunoprecipitation (ChIP)-seq analyses of shoot tissues. Roc10 was found to directly bind to the promoter of PEROXIDASEN/PEROXIDASE38, a key gene in lignin biosynthesis. Together, our findings suggest that Roc10 confers drought stress tolerance by promoting lignin biosynthesis in ground tissues.

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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.

야외시험장과 전자파 완전 무반사실과의 상관계수를 이용한 완전 무반사실의 허용 기준 제안 (Limits of Fully Anechoic Room for Radiated Disturbance Using Correlation Factor)

  • 이순용;정연춘;최재훈
    • 한국전자파학회논문지
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    • 제21권12호
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    • pp.1401-1411
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    • 2010
  • 본 논문에서는 전자파 장해 측정용 야외시험장과 전자파 내성 시험장인 완전 무반사실과의 상관계수를 이용하여 완전 무반사실에서 전자파 허용 기준을 제시하였다. FAR Project(SMT4-CT96-2133), CISPR/A/665/DTR, CISPR A/665/DTR 문서들을 분석하고, 이 문서들과 이론적인 수식들을 이용하여 야외시험장과 완전 무반사실의 이론적인 상관계수를 도출하였다. 실험적인 상관계수를 도출하기 위해서 피시험기기를 제작하였으며, 제작된 피시험기기의 전기장 세기를 10 m 야외시험장과 3 m 완전 무반사실에서 측정하였다. 또한, 다중 소스원을 갖는 피시험기기를 위한 허용 기준을 제시하기 위해서, 전기 다이폴과 자기 다이폴의 방사 이론을 프로그램화 하였다. 이 프로그램을 이용하여 다중 소스원을 갖는 피시험기기를 위한 상관계수를 도출하였다. 이론적, 실험적 상관계수를 이용하여 완전 무반사실에서 전자파 허용 기준을 새롭게 제시함으로써 완전 무반사실이 야외시험장의 전자파 방사(EMI) 대체 시험장으로서 활용될 수 있음을 확인하였다.

Over-expression of Cu/ZnSOD Increases Cadmium Tolerance in Arabidopsis thaliana

  • Cho, Un-Haing
    • Journal of Ecology and Environment
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    • 제30권3호
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    • pp.257-264
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    • 2007
  • Over-expression of a copper/zinc superoxide dismutase (Cu/ZnSOD) resulted in substantially increased tolerance to cadmium exposure in Arabidopsis thaliana. Lower lipid peroxidation and $H_2O_2$ accumulation and the higher activities of $H_2O_2$ scavenging enzymes, including catalase (CAT) and ascorbate peroxidase (APX) in transformants (CuZnSOD-tr) compared to untransformed controls (wt) indicated that oxidative stress was the key factor in cadmium tolerance. Although progressive reductions in the dark-adapted photochemical efficiency (Fv/Fm) and quantum efficiency yield were observed with increasing cadmium levels, the chlorophyll fluorescence parameters were less marked in CuZnSOD-tr than in wi. These observations indicate that oxidative stress in the photosynthetic apparatus is a principal cause of Cd-induced phytotoxicity, and that Cu/ZnSOD plays a critical role in protection against Cd-induced oxidative stress.