• Title/Summary/Keyword: cutoff point

Search Result 103, Processing Time 0.029 seconds

A study of coupling mechanism between two dipoles integrated within a conductor-backed thin dieelectric layer above earth using asymptotic evaluation (점근적 근사를 사용한 지표면 위에 놓여 있는 한쪽 면이 도체로 된 얇은 유전체 층 내부의 두 다이폴 사이의 상호 결합 원리에 관한 연구)

  • 박동국;라정웅
    • Journal of the Korean Institute of Telematics and Electronics D
    • /
    • v.34D no.1
    • /
    • pp.8-13
    • /
    • 1997
  • An electric field due to point dipole within conductor-backed thin dielectric layer above the earth is calculated by using saddle point method When the dielectric layer is thin enough to support a cutoff mdoe, we show that the field may be approximated by sum of contributions of branch points of TE mode and poles of tM mode and that the branch points and poles contributions are interpreted as an evanescent lateral waves and leaky waves, respectively.

  • PDF

Hemoglobin, Hematocrit and Serum Ferritin as Markers of Iron Status (빈혈판정 지표로서의 헤모글로빈, 헤마토크릿 및 혈청 페리틴)

  • 정해랑;문현경;송범호;김미경
    • Journal of Nutrition and Health
    • /
    • v.24 no.5
    • /
    • pp.450-457
    • /
    • 1991
  • The iron status of 57 female college students was evaluated by measurements of hemoglobinCHb). hematocritCHct) and serum ferritin(Ferritin). Mean values for Hb, Hct and Ferritin were $13.9\pm$ 0.96g/dl, $41.4\pm$ 2.85% and $20.7\pm$ l5.5ng/mL respectively. Ferritin as well as Hb. Hct were not statistically different from normal distribution. although ferritin were skewed to the right. The prevalence of anemia defined by Hb < 12g/dI. Hct ~36 % and Ferritin <12ng/ml were found to be 5.3, 10.3 and 36.8%, respectively. By using Hb as a screening tool at a cutoff point of 12g/dI. 2.8% of healthy subjects will be incorrectly classified as anemic and 90.5 % of anemic as healthy. Sensitivity and specificity were calculated at various cutoff points of Hb and Hct. The estimates of sensitivity and specificity allow Hb 14.0g/dl as cutoff point for good predictor of anemia.

  • PDF

The cutoff criterion and the accuracy of the polygraph test for crime investigation (범죄수사를 위한 거짓말탐지 검사(polygraph test)의 판정기준과 정확성)

  • Yu Hwa Han ;Kwangbai Park
    • Korean Journal of Culture and Social Issue
    • /
    • v.14 no.4
    • /
    • pp.103-117
    • /
    • 2008
  • The polygraph test administered by the Korean Prosecutors Office for crime investigations customarily uses the score of -12 as the cutoff point separating the subjects who lie from those who tell the truth. The criterion used by the KPO is different from the one (-13) suggested by Backster (1963) who invented the particular method for lie detection. Based on the signal detection theory applied to the real polygraph test data obtained from real crime suspects by the KPO, the present study identified the score of -8 as an optimal criterion resulting in the highest overall accuracy of the polygraph test. The classification of the subjects with the score of -8 as the criterion resulted in the highest accuracy (83.17%) compared with the accuracies of classifications with the Backster's criterion (76.24%) and the KPO's criterion (80.20%). However, the new criterion was also found to result in more false-positive cases. Based on the results from the present study, it was recommended to use the score of -8 as the criterion when the overall accuracy is important but the score of -12 or -13 when avoiding false-positive is more important than securing the overall accuracy.

  • PDF

What will be the Proper Criteria for Impaired Fasting Glucose for Korean Men? - Based on Medical Screening Data from a General Hospital - (공복혈당장애의 기준 하한치에 관한 코호트연구 - 일개병원 종합건강자료를 중심으로 -)

  • Ryu, Seung-Ho;Kim, Dong-Il;Suh, Byung-Seong;Kim, Woon-Sool;Chang, Yoo-Soo
    • Journal of Preventive Medicine and Public Health
    • /
    • v.38 no.2
    • /
    • pp.203-207
    • /
    • 2005
  • Objectives: Recently, the American Diabetes Association (ADA) redefined the criteria of prediabetes, which has lowered the diagnostic level of fasting plasma glucose (FPG) from 110 to 125 mg/dl, down to levels between 100 to 125mg/dl. The purpose of this study was to determine the predictive cutoff level of FPG as a risk for the development of diabetes mellitus in Korean men. Methods: A retrospective cohort study was conducted on 11,423 (64.5%) out of 17,696 males $\leq$30 years of age, and who met the FPG of $\leq$125 mg/dl and hemoglobin A1c of $\leq$ 6.4% criteria, without a history of diabetes, and who were enrolled at the screening center of a certain university hospital between January and December 1999. The subjects were followed from January 1999 to December 2002 (mean follow-up duration; 2.3(${\pm}0.7$) years). They were classified as normal (FPG <100mg/dl), high glucose (FPG $\geq$100mg/dl and <110mg/dl) and impaired fasting glucose (FPG $\geq$110mg/dl and $\leq$125mg/dl) on the basis of their fasting plasma glucose level measured in 1999. We compared the incidence of diabetes between the 3 groups by performing Cox proportional hazards model and used receiver operating characteristic analyses of the FPG level, in order to estimate the optimal cut-off values as predictors of incident diabetes. Results: At the baseline, most of the study subjects were in age in their 30s to 40s (mean age, 41.8(${\pm}7.1$) year). The incidence of diabetes mellitus in this study was 1.19 per 1,000 person-years (95% CI=0.68-1.79), which was much lower than the results of a community-based study that was 5.01 per 1,000 person-years. The relative risks of incident diabetes in the high glucose and impaired fasting glucose groups, compared with the normal glucose group, were 10.3 (95% CI=2.58-41.2) and 95.2 (95% CI= 29.3-309.1), respectively. After adjustment for age, body mass index, and log triglyceride, a FPG greater than 100mg/dl remained significant predictors of incident diabetes. Using the receiver operating characteristic (ROC) curve, the optimal cutoff level of FPG as a predictor of incident diabetes was 97.5 mg/dl, with a sensitivity and a specificity of 81.0% and 86.0%, respectively. Conclusion: These results suggest that lowering the criteria of impaired fasting glucose is needed in Korean male adults. Future studies on community-based populations, including women, will be required to determine the optimal cutoff level of FPG as a predictor of incident diabetes.

Validation of Critical Care Non-verbal Pain Scale for Critically Ill Patients (중환자 통증사정 도구의 타당성 평가)

  • Choi, Eun Hee;Kim, Jin Hee;Ko, Mi Suk;Kim, Ji Yang;Kwon, Eun Ok;Jang, In Sun
    • Journal of Korean Clinical Nursing Research
    • /
    • v.19 no.2
    • /
    • pp.245-254
    • /
    • 2013
  • Purpose: This study was done to examine predictive validity of Critical Care Non-verbal Pain Scale (CNPS) and develop criteria for pain assessment using CNPS with critically ill patients who have communication problems. Methods: Data were collected from intensive care units at three major general hospitals in Seoul and Kyunggi province. During each observation, a nurse assessed pain severity using CNPS ratings (range 0-9) at four treatment stages: at rest, during central catheter dressing change (nonpainful procedure), position change and suctioning (routine painful procedures). Patients also assessed their pain using a self-report 4-point VRS-4. Results: There were significant differences between the four treatment stages except between "at rest" and "nonpainful procedure". Strong correlations were found between CNPS and VRS-4 for "at rest" (r=.552, p<.001), central catheter dressing change (r=.505, p<.001), position change (r=.709, p<.001), and suctioning (r=.662, p<.001). ROC curve analysis of CNPS based on 3 point on VRS-4 showed the cutoff point was 3 for CNPS, the starting point for pain management with 73% sensitivity, 92.2% specificity, 73% positive predictive value, and 92.8% negative predictive value. Conclusion: Results indicate that CNPS is a valid tool for measuring pain in critically ill patients with communication problems and 3 point should be the standardized pain treatment point.

Diagnostic Potential of Strain Ratio Measurement and a 5 Point Scoring Method for Detection of Breast Cancer: Chinese Experience

  • Parajuly, Shyam Sundar;Lan, Peng Yu;Yun, Ma Bu;Gang, Yang Zhi;Hua, Zhuang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.4
    • /
    • pp.1447-1452
    • /
    • 2012
  • Aim: To evaluate the differential diagnostic potential of lesion stiffness assessed by the sonoelastographic strain index ratio (SR) and elastographic color scoring system (UE) for breast lesions. Materials and Methods: Three hundred and forty two breast masses (158 benign and 184 malignant) from 325 consecutive patients (mean age 44.2 years; range 16-81)who had been scheduled for a sonographically guided core biopsy were examined proposed by Itoh et al, with scoring 1-3=benign and 4-5=malignant. Strain and area ratios of each lesion were calculated within the same machine. Histological diagnosis was used as the reference standard. The area under the curve (AUC) and cut-off point were obtained by receiver operating curve and the cross table Fischer Test was carried out for assessing diagnostic value. Sensitivity, specificity, PPV, NPV, accuracy and false-discovery rates were compared. Results: The mean strain ratios for benign and malignant lesions were 1.87 and 7.9 respectively. (P<0.0001). When a cutoff point of 3.54 was used, SR had a sensitivity of 94.6%, a specificity 94.3%, a PPV of 95.1%, an NPV of 93.7% and an accuracy of 94.4%. The AUC values were 0.90 for the 5 point scoring system (UE) and 0.96 for the strain index ratio. The overall diagnostic performance was SR method was better (P<0.05). Conclusions: Strain ratio measurement could be another effective predictor in elastography imaging besides 5 the point scoring system for differential diagnosis of breast lesions.

Development of Ceramic Filter Using Non Radiative Microstrip Line In Millimeter-Wave (비방사 마이크로 스트립 선로를 이용한 밀리미터 대역의 세라믹 필터 개발)

  • Shin, Cheon-Woo;Kim, Tae-Heon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.32 no.6A
    • /
    • pp.648-656
    • /
    • 2007
  • This paper is about band pass filter, using Ceramics in the condition of center frequency 370Hz at milli-wave. The band pass filter is applied to Broadband Convergence Network, representing WLL(Wireless Local Loop) and LMDS(Local Multi-point Distribution Service). Sticking ceramic between strip line on a dielectric material substrate with which conductor's covers upper and basal surface, One will house the exterior by using structural resonance. In this Non Radiative Microstrip Line Filter structure, based upon simulations, generalized the two formulas finding resonant frequency of 1step ceramic resonator and bandwidth of 4step ceramic resonator. Also, As a result of experiment, using Network Analyzer, about created a experiment of structure based on the simulation result of 4-step ceramic resonator, It showed good characteristic of targeted bandwidth, comparing simulated result of 36.58GHz$\sim$37.650GHz with experimented result of 36.6GHz$\sim$37.65GHz.

A Model for Effective Customer Classification Using LTV and Churn Probability : Application of Holistic Profit Method (고객의 이탈 가능성과 LTV를 이용한 고객등급화 모형개발에 관한 연구)

  • Lee, HoonYoung;Yang, JooHwan;Ryu, Chi Hun
    • Journal of Intelligence and Information Systems
    • /
    • v.12 no.4
    • /
    • pp.109-126
    • /
    • 2006
  • An effective customer classification has been essential for the successful customer relationship management. The typical customer rating is carried out by the proportionally allocating the customers into classes in terms of their life time values. However, since this method does not accurately reflect the homogeneity within a class along with the heterogeneity between classes, there would be many problems incurred due to the misclassification. This paper suggests a new method of rating customer using Holistic profit technique, and validates the new method using the customer data provided by an insurance company. Holistic profit is one of the methods used for deciding the cutoff score in screening the loan application. By rating customers using the proposed techniques, insurance companies could effectively perform customer relationship management and diverse marketing activities.

  • PDF

Utility of False Profile View for Screening of Ischiofemoral Impingement

  • Kwak, Dae-Kyung;Yang, Ick-Hwan;Kim, Sungjun;Lee, Sang-Chul;Park, Kwan-Kyu;Lee, Woo-Suk
    • Hip & pelvis
    • /
    • v.30 no.4
    • /
    • pp.219-225
    • /
    • 2018
  • Purpose: Ischiofemoral impingement (IFI)-primarily diagnosed by magnetic resonance imaging (MRI)-is an easily overlooked disease due to its low incidence. The purpose of this study was to evaluate the usefulness of false profile view as a screening test for IFI. Materials and Methods: Fifty-eight patients diagnosed with IFI between June 2013 and July 2017 were enrolled in this retrospective study. A control group (n=58) with matching propensity scores (age, gender, and body mass index) were also included. Ischiofemoral space (IFS) was measured as the shortest distance between the lateral cortex of the ischium and the medial cortex of lesser trochanter in weight bearing hip anteroposterior (AP) view and false profile view. MRI was used to measure IFS and quadratus femoris space (QFS). The receiver operating characteristics (ROC), area under the ROC curve (AUC) and cutoff point of the IFS were measured by false profile images, and the correlation between the IFS and QFS was analyzed using the MRI scans. Results: In the false profile view and hip AP view, patients with IFI had significantly decreased IFS (P<0.01). In the false profile view, ROC AUC (0.967) was higher than in the hip AP view (0.841). Cutoff value for differential diagnosis of IFI in the false profile view was 10.3 mm (sensitivity, 88.2%; specificity, 88.4%). IFS correlated with IFS (r=0.744) QFS (0.740) in MRI and IFS (0.621) in hip AP view (P<0.01). Conclusion: IFS on false profile view can be used as a screening tool for potential IFI.

A Multicenter Pilot Study of Biliary Atresia Screening Using Digital Stool Color Imaging

  • Kannamon Waitayagitgumjon;Wannisa Poocharoen;Suchin Trirongjitmoah;Kriengsak Treeprapin;Arada Suttiwongsing;Thetiya Wirifai;Chira Trirongchitmoh;Pitiporn Tangkabuanbutr
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • v.27 no.3
    • /
    • pp.168-175
    • /
    • 2024
  • Purpose: The presence of alcoholic stool in biliary atresia (BA) patients is the basis of a stool color card (SCC), a screening tool that has led to more patients receiving Kasai portoenterostomy earlier. This study aimed to evaluate the color image processing of stool images captured using smartphones. We propose that measuring digital color parameters is a more objective method for identifying BA stools and may improve the sensitivity of BA screening. Methods: A prospective study was conducted in five hospitals in Thailand between October 1, 2020, and December 31, 2021. Stools from infants presenting with jaundice, acholic stool, or dark-colored urine were photographed. Digital image color analysis was performed, and software was developed based on the color on the original SCC. Sensitivity and specificity for predicting BA stools were compared between the SCC and the software. Results: Of 33 infants eligible for data collection, 19 were diagnosed with BA. Saturation and blue were two potential digital color parameters used to differentiate BA stools. The receiver operating characteristic curve was used to determine the optimum cutoff point of both values, and when saturation ≤56 or blue ≥61 was set as a threshold for detecting BA stool, high accuracy was achieved at 81.8% and 78.8%, respectively. Conclusion: Digital image processing is a promising technology. With appropriate cutoff values of saturation in hue, saturation, value and blue in red, green, blue color models, BA stools can be identified, and equivocal-colored stools of non-BA patients can be differentiated with acceptable accuracy in infants presenting with jaundice.