• 제목/요약/키워드: high sensitivity

검색결과 4,990건 처리시간 0.031초

Three-Dimensional Modelling and Sensitivity Analysis for the Stability Assessment of Deep Underground Repository

  • Kwon, S.;Park, J.H.;Park, J.W.;Kang, C.H.
    • Nuclear Engineering and Technology
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    • 제33권6호
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    • pp.605-618
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    • 2001
  • For the mechanical stability assessment of a deep underground high-level waste repository. computer simulations using FLAC3D were carried out and important parameters including stress ratio, depth, tunnel size, joint spacing, and joint properties were chosen from sensitivity analysis. The main effect as well as the interaction effect between the important parameters could be investigated effectively using fractional factorial design . In order to analyze the stability of the disposal tunnel and deposition hole in a discontinuous rock mass, different modelings were performed under different conditions using 3DEC and the influence of joint distribution and properties, rock properties and stress ratio could be determined. From the three dimensional modelings, it was concluded that the conceptual repository design was mechanically stable even in a discontinuous rock mass.

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푸리에 변환과 주파수 민감도를 이용한 시변자장 시스템에서의 과도상태 해석 (Transient Analysis of Magnetodynamic Systems Using Fourier Transform and Frequency Sensitivity)

  • 최명준;김창현;박일한
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 A
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    • pp.64-66
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    • 1998
  • This paper presents a new efficient method for transient analysis in magnetodynamic systems of linear eddy current problems. This mehtod employs the Fourier transform and the high-order frequency sensitivity of harmonic finite element method. By taking into account the time-constant of magnetodynamic system, the Fourier integral of continuous frequency is converted into the Fourier series of discrete frequency. And with the results of Fourier series expansion of converted input wave form, the responses of each sinusoids is superposed to give the total response of the magnetodynamic systems. But, if the frequency band of input wave form is broad, it takes long computational time since all responses for each sinusoids must be calculated. Therefore, the high-order frequency sensitivity method is employed to estimate the response variation to frequency. The proposed algorithm is applied to an induction heating system to validate its numerical efficiency.

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전류측정감도 개선을 위한 로고우스키 코일의 설계 (Design of Rogowski coil to improve of current measurement sensitivity)

  • 박정남;이청;장용무;강성화;임기조;나동희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.609-612
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    • 2001
  • Rogowski coil is made having no ferromagnetic material in a core. So the coil cannot be driven into saturation. This result in that Rogowski coils may be calibrated at relatively low currents, and used with confidence at very high currents. However the lowest level of current that can be measured is limited by the sensitivity of the voltage measuring instrument and system noise. Therefore, geometrical effects were investigated in order to measure high sensitivity of low level current and the significant source of error wa examined as well. n the results, the source of error was associated with coil designs, i.e. shape and uniformity of coil and a geometrical location of current source inside and outside of the Rogowski coil.

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오스테나이트계 스테인리스강의 용접성과 내식성에 미치는 합금원소의 영향(I) - 응고균열 감수성을 중심으로 - (The Effect of Alloying Elements on Weldability and Corrosion Resistance of Austenitic Stainless Steels(I))

  • 정호신;이윤용;배동수
    • Journal of Welding and Joining
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    • 제30권3호
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    • pp.57-65
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    • 2012
  • The interest of austenitic heat resistant stainless steels containing high Si has increased because they have higher resistance of oxidation and higher strength at high temperature than STS 310. This study carried out Varestraint test for evaluation of solidification cracking sensitivity of 14 different stainless steels. As a result of Varestraint test, all specimens solidified as primary ferrite, and solidification crack sensitivity increased with adding $N_2$ to shielding gas. Nb and W had beneficial effect on solidification crack resistance in case of less than FN 2 containing, but crack sensitivity increased with Nb and W in case of more than FN 2. Ce had beneficial effect on solidification crack resistance but impaired weld bead appearance.

다감각 운동이 여성노인의 발 바닥 압력감각, 균형에 미치는 영향 (The Effect of Multisensory Exercise on Foot Pressure Sensitivity, Balance for the Elderly)

  • 강지은;이경옥;이태용
    • 한국운동역학회지
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    • 제25권1호
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    • pp.95-101
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    • 2015
  • Objective : The purpose of this study was to analyze the effects of multisensory exercise on foot pressure sensitivity and balance for the elderly. Method : The subjects were 17 elderly women (11 for the experimental group and 6 for the control group) with a mean age of 83. The subjects all lived in senior residence centers in Seoul. Multisensory exercise was done twice a week for 40 minutes during a 12 week period. Exercise programs were changed every 3 weeks according to the principal of gradual progress of the exercise. In order to train the vision system subjects were asked to open and close their eyes during exercise. When it came to training the vestibular system, subjects stood and walked on high elastic mats with their bare feet. For the somatasensory system subjects always stood and walked with their bare feet. The sub-Metatarsal Pad Elasticity Acquisition Instrument (MPEAI) was used to measure foot pressure sensitivity. MFT Balance test (V1.7) was used to measure anterior / posterior and medial / lateral directional balance. For the statistical analysis the IBM SPSS 21.0 was used to perform Repeatde measured ANOVA and Wilcoxon ranked test. Results : For the multisensory exercise group Hallux (after 6 weeks, 12 weeks), heel (after 6 weeks) and 2nd Metartarsal $40^{\circ}$ (after 6 weeks) pressure sensitivity increased statistically, but the control group didn't change. Also, balance didn't change for the experimental and control group statistically. Conclusion : Exercise with bare feet on a high elastic mat had a partially positive effect on foot sensitivity.

An association of urinary sodium-potassium ratio with insulin resistance among Korean adults

  • Park, Yeong Mi;Kwock, Chang Keun;Park, Seyeon;Eicher-Miller, Heather A.;Yang, Yoon Jung
    • Nutrition Research and Practice
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    • 제12권5호
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    • pp.443-448
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    • 2018
  • BACKGROUND/OBJECTIVES: This study was conducted to investigate the effects of sodium-potassium ratio on insulin resistance and sensitivity in Korean adults. SUBJECTS/METHODS: Subjects were 3,722 adults (1,632 men and 2,090 women) aged 40-69 years participating in the Korean genome and epidemiology study_Ansan and Ansung study. Insulin resistance was assessed using homeostasis model assessment of insulin resistance (HoMA-IR) and fasting insulin, and insulin sensitivity was assessed by using the quantitative insulin sensitivity check index (QUICKI). The 24-h urinary sodium and potassium excretion were estimated from spot urinary samples using the Tanaka formula. The generalized linear model was applied to determine the association between urinary sodium-potassium ratio and insulin resistance. RESULTS: HoMA-IR (P-value = 0.029, P-trend = 0.008) and fasting insulin (P-value = 0.017, P-trend = 0.005) levels were positively associated with 24-h estimated urinary sodium-potassium ratio in the multivariable model. QUICKI was inversely associated with 24-h estimated urinary sodium-potassium ratio in all models (P-value = 0.0002, P-trend < 0.0001 in the multivariate model). CONCLUSION: The present study suggests that high sodium-potassium ratio is related to high insulin resistance and low insulin sensitivity. Decreasing sodium intake and increasing potassium intake are important for maintaining insulin sensitivity. Further studies are needed to confirm these findings in longitudinal studies.

Effects of Critical Thinking Disposition and Empathy on Cultural Competency in Dental Hygiene Students

  • Hwang, Ji-Min;Han, Ji-Hyoung
    • 치위생과학회지
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    • 제18권1호
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    • pp.24-31
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    • 2018
  • This study investigated the effects of critical thinking and empathy on the cultural competence of dental hygienists and students. A total of 529 dental hygiene students were randomly sampled and included as subjects. PASW Statistics for Windows ver. 18.0 was used to obtain the following results. Among the critical thinking sub-domains, cognitive integration was the highest and the lowest. Empathic ability had the highest acceptance factor among the sub-domains. Cultural competence was the highest among the sub-domains, while cultural knowledge was the lowest. According to their general characteristics, subject age, grade, religion, and economic level influenced the cultural capacity. Cultural awareness and sensitivity were high when there were foreign visiting experiences. Cultural awareness, sensitivity, skills, and knowledge were high when subjects had experienced multicultural education (p<0.05). Cultural awareness, sensitivity, skill, experience, and knowledge were correlated with critical thinking and cultural competence, among which cultural sensitivity showed the highest correlation (p<0.001). There was a correlation between cultural awareness and sensitivity, skill, and experience among the empathy and cultural competency sub-domains (p<0.001). The factors influencing cultural awareness included intellectual integration, openness, prudence, and perspective-taking (p<0.001). The factors influencing cultural sensitivity included intellectual integration, openness, and empathic concern (p<0.001). The factors influencing cultural skill included intellectual integration, creativity, and conductivity (p<0.001). The factors influencing cultural experience included prudence, objectivity, perspective-taking, and personal distress (p<0.001). Finally, the factors influencing cultural knowledge included creativity and conductivity (p<0.001). The results indicate that dental hygiene students should be equipped with cultural competence to enhance critical thinking and empathy required by the modern society and optimized dental hygiene courses should be provided for multicultural subjects.

다이아그리드 구조 시스템의 횡적 거동에 대한 민감도 해석 (Sensitivity Analysis on the Lateral Behavior of Diagrid Structure)

  • 안근우;양재광;박성수
    • 한국구조물진단유지관리공학회 논문집
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    • 제19권3호
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    • pp.73-82
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    • 2015
  • 지진하중 풍하중 등에 의한 횡적 거동 분석시, 민감도 해석은 구조 모델의 입력변수의 변화에 따른 횡적 거동의 특성을 분석하고 그에 따른 상대적 주요 변수를 찾는 것을 목적으로 한다. 따라서 민감도 해석은 건축물의 구조 진단과 보수 보강 분야에서 특히 중요하다. 본 논문에서는 동일한 높이에서 다이아그리드 가새부재의 설치 각도를 변화 시키면서 TDA이론을 적용한 선형정적 해석법으로 민감도 해석을 수행하였다. 지진하중의 영향이 큰 중층 건축물에서는 모듈의 설치 각도가 $58^{\circ}$일 때 가새부재가 가장 주요한 변수로 판별되었고, 풍하중의 영향이 큰 고층 건축물에서는 모듈의 설치 각도가 $67.4^{\circ}$일 경우 가새부재가 가장 주요한 변수로 판별되어 시스템 적용의 효율성을 입증하였다. 또한 구간별 민감도는 12층에서 36층 모델의 경우 중상층부에서 가장 크게 나타났으며, 고층 건축물의 경우 하부에서 가장 큰 민감도값이 산출되었다.

Sensitivity of the Pyrenophora teres Population in Algeria to Quinone outside Inhibitors, Succinate Dehydrogenase Inhibitors and Demethylation Inhibitors

  • Lammari, Hamama-Imene;Rehfus, Alexandra;Stammler, Gerd;Benslimane, Hamida
    • The Plant Pathology Journal
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    • 제36권3호
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    • pp.218-230
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    • 2020
  • Net blotch of barley caused by Pyrenophora teres (Died.) Drechsler, is one of the most destructive diseases on barley in Algeria. It occurs in two forms: P. teres f. teres and P. teres f. maculata. A total of 212 isolates, obtained from 58 fields sampled in several barley growing areas, were assessed for fungicide sensitivity by target gene analysis. F129L and G137R mitochondrial cytochrome b substitution associated with quinone outside inhibitors (QoIs) resistance, and succinate dehydrogenase inhibitors (SDHIs) related mutations (B-H277, C-N75S, C-G79R, C-H134R, and C-S135R), were analyzed by pyrosequencing. In vitro sensitivity of 45 isolates, towards six fungicides belonging to three chemical groups (QoI, demethylase inhibitor, and SDHI) was tested by microtiter technique. Additionally, sensitivity towards three fungicides (azoxystrobin, fluxapyroxad, and epoxiconazole) was assessed in planta under glasshouse conditions. All tested isolates were QoI-sensitive and SDHI-sensitive, no mutation that confers resistance was identified. EC50 values showed that pyraclostrobin and azoxystrobin are the most efficient fungicides in vitro, whereas fluxapyroxad displayed the best disease inhibition in planta (81% inhibition at 1/9 of the full dose). The EC50 values recorded for each form of net blotch showed no significant difference in efficiency of QoI treatments and propiconazole on each form. However, in the case of fluxapyroxad, epoxiconazole and tebuconazole treatments, analysis showed significant differences in their efficiency. To our knowledge, this study is the first investigation related to mutations associated to QoI and SDHI fungicide resistance in Algerian P. teres population, as well as it is the first evaluation of the sensitivity of P. teres population towards these six fungicides.