• 제목/요약/키워드: sensitivity study

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The Changes in Contrast Sensitivity and Glare Sensitivity when Wearing Circle Contact Lenses after the Refractive Surgery (시력교정술 후 써클콘택트렌즈 착용 시 대비감도 및 눈부심감도 변화)

  • Kwon, Ki Nam;Park, Sang Hee;Kim, So Ra;Park, Mijung
    • Journal of Korean Ophthalmic Optics Society
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    • v.21 no.1
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    • pp.23-34
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    • 2016
  • Purpose: In the present study, the effect of circle contact lenses wear on contrast sensitivity and glare sensitivity in a refractive surgery group was investigated. Methods: The contrast sensitivity and glare sensitivity were evaluated using by CGT-1000 for a non-refractive surgery group as control group(40 eyes) and a refractive surgery group(30 eyes) applied plano circle contact lenses, and pupil size was also measured. The correlation between contrast/glare sensitivity and the pupil size was analyzed. Results: In the refractive surgery group, contrast sensitivity in the range of high spatial frequency decreased with wearing circle contact lenses, and amount of decrease for the refractive surgery group was larger than for the control group. The correlation between pupil size and the change of contrast sensitivity was decreased by wearing circle contact lenses, and the correlation was lower in the refractive surgery group than the control group. Furthermore, the wear of circle contact lenses affected on glare sensitivity. In analyzing the change of glare sensitivity by pupil size, the glare was larger in the refractive surgery group than control group. Circle contact lenses in refractive surgery group were not fitted on the center of cornea. Conclusions: In the present study, it is suggested that the sufficient understanding and consideration about the decrease of contrast sensitivity and the increase of glare by wearing circle contact lenses after the refractive surgery is necessary.

Accuracy, Sensitivity and Specificity of Fine Needle Aspiration Biopsy for Salivary Gland Tumors: A Retrospective Study from 2006 to 2011

  • Silva, William P P;Stramandinoli-Zanicotti, Roberta T;Schussel, Juliana L;Ramos, Gyl H A;Ioshi, Sergio O;Sassi, Laurindo M
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.11
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    • pp.4973-4976
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    • 2016
  • Objective: This article concerns evaluation of the sensitivity, specificity and accuracy of FNAB for pre-surgical diagnosis of benign and malignant lesions of major and minor salivary glands of patients treated in the Department of Head and Neck Surgery of Erasto Gartner Hospital. Methods: This retrospective study analyzed medical records from January 2006 to December 2011 from patients with salivary gland lesions who underwent preoperative FNAB and, after surgical excision of the lesion, histopathological examination. Results: The study had a cohort of 130 cases, but 34 cases (26.2%) were considered unsatisfactory regarding cytology analyses. Based on the data, sensitivity was 66.7% (6/9), specificity was 81.6% (71/87), accuracy was 80.2% (77/96), the positive predictive value was 66,7% (6/9) and the negative predictive value was 81.6% (71/87). Conclusion: Despite the high rate of inadequate samples obtained in the FNAB in this study the technique offers high specificity, accuracy and acceptable sensitivity.

Estimating Ozone Sensitivity Coefficients to NOx and VOC Emissions Using BFM and HDDM for A 2007 June Episode (HDDM과 BFM을 이용한 NOx와 VOC 배출량에 대한 오존민감도계수 산정 및 결과 비교: 2007년 6월 수도권 사례)

  • Kim, Soon-Tae
    • Journal of Environmental Science International
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    • v.20 no.11
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    • pp.1465-1481
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    • 2011
  • The accuracy of ozone sensitivity coefficients estimated with HDDM (High-order Decoupled Direct Method) can vary depending on the $NO_x$ (Nitrogen Oxides) and VOC (Volatile Organic Compound) conditions. In order to evaluate the applicability of HDDM over the Seoul Metropolitan Area (SMA) during a high ozone episode in 2007 June, we compare BFM (Brute Force Method) and HDDM in terms of the $1^{st}$-order ozone sensitivity coefficient to explain ozone change in response to changes in NOx and VOC emissions, and the $2^{nd}$-order ozone sensitivity coefficient to represent nonlinear response of ozone to the emission changes. BFM and HDDM estimate comparable ozone sensitivity coefficients, exhibiting similar spatial and temporal variations over the SMAduring the episode. NME (Normalized Mean Error) between BFM and HDDM for the episode average $1^{st}$- and $2^{nd}$-order ozone sensitivity coefficients to NOx and VOC emissions are less than 3% and 9%, respectively. For the daily comparison, NME for the $1^{st}$- and $2^{nd}$-order ozone sensitivity coefficients are less than 4% ($R^2$ > 0.96) and 15% ($R^2$ > 0.90), respectively. Under the emission conditions used in this study, two methods show negative episode average $1^{st}$-order ozone sensitivity coefficient to $NO_x$ emissions over the core SMA. The $2^{nd}$-order ozone sensitivity coefficient to $NO_x$ emissions leads ozone to respond muchnonlinear to the reduction in $NO_x$ emissions over Seoul. Nonlinear ozone response to reduction in VOC emissions is mitigated due to the $2^{nd}$-order ozone sensitivity coefficient which is much smaller than the $1^{st}$-order ozone sensitivity coefficient to the emissions in the magnitude.

Sensitivity Analysis for Generalized Nonlinear Implicit Quasi-variational Inclusions

  • Jeong, Jae Ug
    • Kyungpook Mathematical Journal
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    • v.46 no.3
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    • pp.345-356
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    • 2006
  • In this paper, by using the concept of the resolvent operator, we study the behavior and sensitivity analysis of the solution set for a new class of parametric generalized nonlinear implicit quasi-variational inclusion problem in $L_p(p{\geq}2)$ spaces. The results presented in this paper are new and generalize many known results in this field.

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A Study on the Sensitivity Analysis of GERT Network (GERT Network의 감도분석(感度分析)에 관한 고찰(考察))

  • Lee, Sang-Do;Jeong, Jung-Hui;Park, Gi-Ju
    • Journal of Korean Institute of Industrial Engineers
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    • v.9 no.2
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    • pp.47-53
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    • 1983
  • In this paper, a sensitivity analysis is proceeded to improve the network of manufacturing process by converting the qualitative network into GERT Network and by finding equivalent probability, MFG's of variables and sensitivity equation in GERT Network. Sensitivity analysis of GERT Network is important in evaluating, reviewing and improving system. System improvement in GERT Network is achieved by increasing the equivalent probability and by decreasing the equivalent time.

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Sensitivity Enhancement of a Vertical-Type CMOS Hall Device for a Magnetic Sensor

  • Oh, Sein;Jang, Byung-Jun;Chae, Hyungil
    • Journal of electromagnetic engineering and science
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    • v.18 no.1
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    • pp.35-40
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    • 2018
  • This study presents a vertical-type CMOS Hall device with improved sensitivity to detect a 3D magnetic field in various types of sensors or communication devices. To improve sensitivity, trenches are implanted next to the current input terminal, so that the Hall current becomes maximum. The effect of the dimension and location of trenches on sensitivity is simulated in the COMSOL simulator. A vertical-type Hall device with a width of $16{\mu}m$ and a height of $2{\mu}m$ is optimized for maximum sensitivity. The simulation result shows that it has a 23% better result than a conventional vertical-type CMOS Hall device without a trench.

Low-discrepancy sampling for structural reliability sensitivity analysis

  • Cao, Zhenggang;Dai, Hongzhe;Wang, Wei
    • Structural Engineering and Mechanics
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    • v.38 no.1
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    • pp.125-140
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    • 2011
  • This study presents an innovative method to estimate the reliability sensitivity based on the low-discrepancy sampling which is a new technique for structural reliability analysis. Two advantages are contributed to the method: one is that, by developing a general importance sampling procedure for reliability sensitivity analysis, the partial derivative of the failure probability with respect to the distribution parameter can be directly obtained with typically insignificant additional computations on the basis of structural reliability analysis; and the other is that, by combining various low-discrepancy sequences with the above importance sampling procedure, the proposed method is far more efficient than that based on the classical Monte Carlo method in estimating reliability sensitivity, especially for problems of small failure probability or problems that require a large number of costly finite element analyses. Examples involving both numerical and structural problems illustrate the application and effectiveness of the method developed, which indicate that the proposed method can provide accurate and computationally efficient estimates of reliability sensitivity.

Sensitivity Analysis of Fiber Optic Hydrophone for Hollow Cylindrical Mandrel (중공 원통형 광섬유 하이드로폰의 감도 해석)

  • 김정석;윤형규;설재수;남성현
    • Journal of KSNVE
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    • v.9 no.3
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    • pp.565-569
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    • 1999
  • Recently, fiber optic hydrophone is a subject which has attracted as a underwater acoustic sensor. In this study, Finite element modeling of fiber optic hydrophone for hollow cylindrical mandrel was performed and the acoustic sensitivity was calculated to estimate the performance of single element fiber optic hydrophone. And acoustic sensitivity was measured in acoustic water tank to verify the result of simulation. The result of FE analysis and experiment is -126 dB re rad/$\mu$ Pa and -128 dB re rad/$\mu$ Pa respectively.

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TOPOLOGICAL SENSITIVITY AND ITS STRONGER FORMS ON SEMIFLOWS

  • Ruchi Das;Devender Kumar;Mohammad Salman
    • Bulletin of the Korean Mathematical Society
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    • v.61 no.1
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    • pp.247-262
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    • 2024
  • In this paper we introduce and study the notions of topological sensitivity and its stronger forms on semiflows and on product semiflows. We give a relationship between multi-topological sensitivity and thick topological sensitivity on semiflows. We prove that for a Urysohn space X, a syndetically transitive semiflow (T, X, 𝜋) having a point of proper compact orbit is syndetic topologically sensitive. Moreover, it is proved that for a T3 space X, a transitive, nonminimal semiflow (T, X, 𝜋) having a dense set of almost periodic points is syndetic topologically sensitive. Also, wherever necessary examples/counterexamples are given.

Price Sensitivity, Repurchasing and Switching Intention of Internet Fashion Consumers (인터넷 패션 소비자의 가격민감도와 재구매 및 전환의도에 관한 연구)

  • Lee, Eun-Jin
    • Journal of the Korean Society of Clothing and Textiles
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    • v.39 no.1
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    • pp.106-120
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    • 2015
  • This study analyzed the effects of website and consumer's characteristics on price sensitivity as well as the effects of price sensitivity on repurchasing and switching intention. It ascertains differences in: website and consumer's characteristics, price sensitivity, and repurchasing and switching intention according to type of internet shopping mall. A survey was conducted from July 10 to August 20 in 2013, and 492 responses were used for data analysis. As a result, the reputation, ease of price search, and depth of product information positively influenced the price search and the interactivity of website characteristics positively influenced price importance. Product knowledge and information search of fashion consumers positively influenced price sensitivity. Also, the price sensitivity of internet fashion consumer positively influenced repurchasing intention. The price search positively affected the switching intention, while the price importance negatively affected the switching intention. Last, there were significant differences in the reputation, ease of price search, information search, price sensitivity, repurchasing and switching intention according to type of internet shopping mall.