• Title/Summary/Keyword: Reliability Sensitivity

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A Study on the Fire Safety Assessment of a Ship (선박의 화재안전도에 관한 연구)

  • Jung-Hoon Lee;Jae-Ohk Lee;Young-Soon Yang
    • Journal of the Society of Naval Architects of Korea
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    • v.38 no.1
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    • pp.116-122
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    • 2001
  • In this paper, to make a base of the fire safety assessment about ship's fire protection design and Classification Society rule, statistical informations and modeling techniques for the fire safety engineering are investigated and probabilistic safety assessment methods in the structural reliability engineering are introduced. FSEM(Fire Safety Evaluation Module) developed in this paper calculates the probability of fatality, which can be used as an index of fire safety. FSEM is used to calculate the probability of fatality of the evacuees in a small room installed according to the rules for fire-proof. Sensitivity analysis is executed to investigate FSEM's applicability to ship. From results, the necessity of new criterion for ship's fire safety design, the need to study the human behavior in the evacuation from fire, and the development of new fire progress model considering special situations in ships are acknowledged.

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New K-Ar dating system in Korea Basic Science Institute: Summary and Performance (한국기초과학지원연구원에 도입된 K-Ar 연대 측정시스템: 개요 및 성능)

  • 김정민
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.172-178
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    • 2001
  • K-Ar dating system of Korea Basic Science Institute (KBSI) was installed in 1997 and has been used since then. The system consists of high temperature graphite furnace, gas purification system, and mass spectrometer with data acquisition system. K-Ar age is determined by the measurement of the concentrations of Ar and K through isotope dilution method using $^{38}Ar$ as spike and flame spectroscopy, respectively. The accuracy and reliability for the K-Ar age are checked using the several K-Ar standard materials. Although the exact age determination for young samples of less than 1 Ma is hampered by small fluctuations of sensitivity and mass discrimination, the present system yields the reliable K-Ar age compared to the standard materials of Tertiary and Mesozoic age. The measurements for the SORI93 biotite with the recommended K-Ar age of $92.6\pm$0.6 Ma and Bern4M muscovite of $18.5\pm$0.6 Ma yield the reliable age of $92.1\pm$1.1 Ma and $17.8\pm$0.2 Ma, respectively.

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Validity of Needle Aspiration Cytology and Frozen Section in Thyroid Tumor (갑상선 결절에서 세침흡인검사와 동결조직검사의 의의)

  • Kim Jae-Won;Lee Jang-Won;Bae Sung-Ho;Ko Kook-Jin;Yoon Suk-Young;Kim Young-Mo
    • Korean Journal of Head & Neck Oncology
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    • v.20 no.2
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    • pp.143-146
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    • 2004
  • Background and Object: The role of fine needle aspiration cytology (FNAC) and frozen section (FS) in management of thyroid neoplasms continues to generate considerable controversy. We reviewed our current experience to determine the clinical utility of FNAC and FS in our surgical management and investigated reliability of FNAC and FS in planning the extent of thyroid resection. Material and Method: 212 patients who had operations for thyroid disease from May 1996 to November 2003 were included our retrospective study. FNAC was undertaken in 175 patients and FS was done in 148 patients. Result: The sensitivity and specificity of FNAC were 72.1% and 100%, respectively, and those of FS were 67.2% and 100%. The results of FNAC were benign (n=72) , malignancy (n=31), indeterminate (n=9), and nondiagnostic (n=63). The results of FS were benign (n=95), and malignancy (n=53). The 9 indeterminate cases on FNAC were benign (n=6) and malignancy (n=3) on final pathology, and benign (n=7) and malignancy (n=2) on FS. The false negative of FNAC were micro papillary carcinoma (n=6) and follicular carcinoma (n=6). The false negative of FS were micropapillary carcinoma (n=10) and follicular carcinoma (n=2). Conclusion: When results of FNAC are interpreted as indeterminate, FS is a valuable tool. FS is helpful in determining the extent of thyroidectomy when results of FNAC were follicular neoplasm. However we always concerned about micropapillary carcinoma and follicular carcinoma although FNAC and FS were benign.

Drivers' Acceptable levels of the Accuracy of Travel Time Information and Their Valuations (통행시간 정보 정확도에 대한 운전자들의 허용수준과 화폐가치)

  • Yu, Jeong Whon;Choi, Seo Yoon
    • International Journal of Highway Engineering
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    • v.14 no.6
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    • pp.139-148
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    • 2012
  • PURPOSES : The accuracy of travel time information is a key measure of effectiveness and reliability of advanced traveler information systems. This study aims at investigating drivers' perception on the acceptable level of information accuracy and their corresponding valuations. METHODS : A questionnaire survey was executed for collecting driver perception data to capture the expectation level of travel time information provided and their willingness to pay for the information. A Tobit model was adopted for exploring the relationship among the acceptable level, driver socioeconomic characteristics and travel attributes. Since drivers' willingness to pay for accurate travel time information can be different according to their travel lengths, a piecewise linear regression model was developed to capture the sensitivity of values of travel time information to travel length. RESULTS : The analysis results suggest that trip purpose and travel time are two dominant factors to determine drivers' acceptable level of travel time information. For business and short trips, drivers want more accurate information than for non-business and long trips. Drivers' willingness to pay for travel time information also varies depending on their incomes, trip purposes and travel lengths. The results also show that drivers' valuation of travel time information provided is sensitive to their travel length. For longer trips, drivers are less sensitive to travel time information and then put less value on the information provided. CONCLUSIONS : Censored nonlinear regression models are developed to estimate drivers' acceptable accuracy for travel time information and their valuation using questionnaire survey data. The findings on drivers perception to the required accuracy of travel time information and their corresponding willingness to pay can be used in the design and deployment of advanced traveler information system to improve its effectiveness and usefulness through high compliance.

Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

  • Lee, Jae Eun;Lee, Jae Young;Kim, Hong Rye;Shin, Hyun Young;Lin, Tao;Jin, Dong Il
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.6
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    • pp.788-795
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    • 2015
  • Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum.

The use of data mining methods for dystocia detection in Polish Holstein-Friesian Black-and-White cattle

  • Zaborski, Daniel;Proskura, Witold S.;Grzesiak, Wilhelm
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.11
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    • pp.1700-1713
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    • 2018
  • Objective: The aim of this study was to verify the usefulness of artificial neural networks (ANN), multivariate adaptive regression splines (MARS), naïve Bayes classifier (NBC), general discriminant analysis (GDA), and logistic regression (LR) for dystocia detection in Polish Holstein-Friesian Black-and-White heifers and cows and to indicate the most influential predictors of calving difficulty. Methods: A total of 1,342 and 1,699 calving records including six categorical and four continuous predictors were used. Calving category (difficult vs easy or difficult, moderate and easy) was the dependent variable. Results: The maximum sensitivity, specificity and accuracy achieved for heifers on the independent test set were 0.855 (for ANN), 0.969 (for NBC), and 0.813 (for GDA), respectively, whereas the values for cows were 0.600 (for ANN), 1.000 and 0.965 (for NBC, GDA, and LR), respectively. With the three categories of calving difficulty, the maximum overall accuracy for heifers and cows was 0.589 (for MARS) and 0.649 (for ANN), respectively. The most influential predictors for heifers were an average calving difficulty score for the dam's sire, calving age and the mean yield of the farm, where the heifer was kept, whereas for cows, these additionally included: calf sex, the difficulty of the preceding calving, and the mean daily milk yield for the preceding lactation. Conclusion: The potential application of the investigated models in dairy cattle farming requires, however, their further improvement in order to reduce the rate of dystocia misdiagnosis and to increase detection reliability.

Validation of Electrical Impedance Tomography Qualitative and Quantitative Values and Comparison of the Numeric Pain Distress Score against Mammography

  • Juliana, Norsham;Shahar, Suzana;Chelliah, Kanaga Kumari;Ghazali, Ahmad Rohi;Osman, Fazilah;Sahar, Mohd Azmani
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.14
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    • pp.5759-5765
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    • 2014
  • Electrical impedance tomography (EIT) is a potential supplement for mammogram screening. This study aimed to evaluate and feasibility of EIT as opposed to mammography and to determine pain perception with both imaging methods. Women undergoing screening mammography at the Radiology Department of National University of Malaysia Medical Centre were randomly selected for EIT imaging. All women were requested to give a pain score after each imaging session. Two independent raters were chosen to define the image findings of EIT. A total of 164 women in the age range from 40 to 65-year-old participated and were divided into two groups; normal and abnormal. EIT sensitivity and specificity for rater 1 were 69.4% and 63.3, whereas for rater 2 they were 55.3% and 57.0% respectively. The reliability for each rater ranged between good to very good (p<0.05). Quantitative values of EIT showed there were significant differences in all values between groups (ANCOVA, p<0.05). Interestingly, EIT scored a median pain score of $1.51{\pm}0.75$ whereas mammography scored $4.15{\pm}0.87$ (Mann Whitney U test, p<0.05). From these quantitative values, EIT has the potential as a health discriminating index. Its ability to replace image findings from mammography needs further investigation.

A study on the Severity Scoring Systems of Atopic Dermatitis ; comparison, Analysis and Establishment of childhood patients in Oriental Medicine (아토피 피부염의 중증도 평가방법에 대한 제언 ; 비교 분석 및 소아 환자의 평가방법에 대한 설립)

  • Seo, Jung-Min;Kim, Sang-Chan;Hwang, Sun-Yi;Hwang, Bo-Min;Jee, Seon Young;Lee, Sang-Gon;Baek, Jung-Han
    • The Journal of Pediatrics of Korean Medicine
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    • v.20 no.1
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    • pp.1-14
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    • 2006
  • Objective : As prevalence of atopic dermatitis(AD) rises and medicine of atopic dematitis develops, the methods of measurement for atopic dermatitis have developed. Therefore, we aimed to establish a new sconring system in oriental medicine for a childhood atopic dematitis, by comparison, analysis of various sconing systems. Method : We searched for the data related to severity sconing systems of atopic dermatitis in Entrez PubMed on abroad thesis and KISS(Korenstdued Information Service System) on domestic thesis from 1990 to 2005. Result : Severity sconing systems for atopic dermatitis satisfy validity, reliability, sensitivity of change and verification of this. The essential items of severity sconing systems are extent, intensity and subjective symptoms. The lesion is divided into 9 areas(head and neck, upper limbs, elbow, hands, trunk, hip and inguinal, lower limbs, knee, feet). The items of intensity are erythema, oedema and induration and papulation, oozing and weeping and erosion, excorition, scaling, lichenification. The subjective symptom is pruritis, evaluated according to sleep loss and obstruction of play and study. The extent and intensity is evaluated in combination. We suggested that extent and intensity occupied for 70% and subject symptoms accounted for 30% of total score.

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Studies on Probabilistic Nonlinear First Ply Failure Loads and Buckling Loads of Laminated Composite Panels (적층복합재료 패널의 확률론적 비선형 초기파단하중 및 좌굴하중에 관한 연구)

  • Bang, Je-Sung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.6
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    • pp.1-10
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    • 2013
  • Probabilistic nonlinear first ply failure loads of flat composite panels and nonlinear buckling loads of curved composite panels with cutouts are estimated to provide the more reliable main load carrying structure in the renewable energy industry and offshore structures. The response surface method approximates limit state surface to a second order polynomial form of random variables with the results of deterministic finite element analyses at given sampling design points. Furthermore, the iterative linear interpolation scheme is used to obtain a more accurate approximation of the limit state surface near the most probable failure point (MPFP). The advanced first order second moment method and the Monte Carlo method are performed on an approximated limit state surface to evaluate the probability of failure. Finally, the sensitivity of the reliability index with respect to transformed random variables is investigated to figure out the main random variables that have an effect on failures.

Fault Detection Performance Analysis of GNSS Integrity RAIM (GNSS 무결성을 위한 RAIM 기법의 고장검출 성능 분석)

  • Kim, Ji Hye;Park, Kwan Dong;Kim, Du Sik
    • Journal of Korean Society for Geospatial Information Science
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    • v.20 no.3
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    • pp.49-56
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    • 2012
  • Performance analysis on RAIM, which is one of the techniques for monitoring integrity to ensure the reliability of GPS, was conducted in this study. RAIM is such a method which allows its user to monitor integrity in the stand-alone mode. Among the existing RAIM procedures, the representative methods including the RCM (Range Comparison Method), LSRM (Least Square Residual Method), Parity approach and WRAIM (Weighted RAIM) were evaluated, and their performance was analyzed. To validate the performance of the implemented algorithms, fault detection was tried on the clock malfunctioning event of PRN 23 occurred on January 1st, 2004. As a result, it was identified that the LSRM and the WRAIM detected all the faults happened in the event. In the case of RCM, all the states of fault were detected except for the error which occurred as a false alarm at one epoch. Furthermore, simulated biases were added for each satellite to analyze the sensitivity of each algorithm. Consequently, when biases of the 9-13 meters range were simulated for the RCM and LSRM algorithm, all the malfunctions were detected. For the WRAIM method, it could detect range biases greater than 15 meters.