• 제목/요약/키워드: area under curve

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로지스틱 회귀분석과 의사결정나무 분석을 이용한 일 대도시 주민의 우울 예측요인 비교 연구 (Comparative Analysis of Predictors of Depression for Residents in a Metropolitan City using Logistic Regression and Decision Making Tree)

  • 김수진;김보영
    • 한국콘텐츠학회논문지
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    • 제13권12호
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    • pp.829-839
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    • 2013
  • 본 연구는 로지스틱 회귀분석과 의사결정나무 분석을 활용하여 일 대도시 주민의 우울에 영향을 주는 요인을 예측하고 비교하고자 시도된 서술적 조사연구이다. 연구대상은 20세에서 65세 미만의 일 대도시 주민 462명이었다. 자료 수집은 2011년 10월 7일부터 10월 21일까지이었으며, 자료 분석은 SPSS 18.0 프로그램을 이용하여 빈도, 백분율, 평균과 표준편차 및 ${\chi}^2$-test, t-test, 로지스틱 회귀분석, roc curve, 의사결정나무 분석으로 분석하였다. 본 연구 결과, 로지스틱 회귀분석과 의사결정나무 분석에서 공통적으로 나타난 우울 예측요인은 사회부적응, 주관적 신체증상 및 가족 지지이었다. 로지스틱 회귀분석에서 특이도 93.8%, 민감도 42.5%이었고, 본 연구의 모형 적합도를 roc curve 검증 한 결과 AUC=.84으로 본 연구 모형은 적합(p=<.001)하다고 할 수 있다. 우울예측에 대한 의사결정나무 분석은 분류에 대한 예측 정확도에서 특이도 98.3%, 민감도 20.8%이었고, 전체 분류 정확도는 로지스틱 회귀분석은 82.0%, 의사결정나무 분석은 80.5% 이었다. 본 연구 결과 민감성과 분류 정확도와 더 높게 나타난 로지스틱 회귀분석 방법이 지역 주민의 우울 예측 모형을 구축하는데 더 유용한 자료로 사용될 수 있으리라 사료된다.

주요 곡류의 혈당반응 및 쌀기준 혈당지수 측정 (Blood Glucose Response to Some Cereals and Determination of Their Glycemic Index to Rice as Standard Food)

  • 이정선
    • Journal of Nutrition and Health
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    • 제30권10호
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    • pp.1170-1179
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    • 1997
  • This study was designed to determine blood glucose responses to some cereals produced in Korea. The levels of blood glucose were measured over 2 hours after feeding healthy vounteers with 50g carbohydrate portions. The glycemic index(GI)k and glycemic index-rice(GI-rice) of a food has been defined as : GI=mean of (blood glucose response area of test food/ blood glucose response area of glucose taken by the same indicidual) $\times$100 and GI-rice=mean of (blood glucose response area of test food/blood glucose response area of rice taken by the same individual) $\times$100. The area under the curve is taken to be the area above the fasting value calculated geometrically from blood glucose increments. The GI of barely to glucose as the standard(57$\pm$7) was significantly (p<0.05) lower than those of other cereals whereas the GI of glutinous rice (110$\pm$8) was significantly (p<0.05) higher than other those of cereals. The GI values to rice as the standard were 63 $\pm$6 for barley, 79$\pm$5 for buckwheat, 85$\pm$6 for foxtail millet, 90$\pm$12 for unpolished rice, 100$\pm$0 for rice, 102$\pm$7 for glutinous rice, 106 $\pm$6 for unpolished glutinous rice, 115$\pm$13 for glutinous millet, 116$\pm$13 fro job's tear, and 122 $\pm$ 4 glutinous sorghum. The mean GI-rice was identical to the mean of the adjusted GI values, with a correlation coefficient of r=0.964(p<0.0001). This finding suggests that white rice could be used as standard food for the determination of GI.

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The Effect of Uncinate Process Resection on Subsidence Following Anterior Cervical Discectomy and Fusion

  • Lee, Su Hun;Lee, Jun Seok;Sung, Soon Ki;Son, Dong Wuk;Lee, Sang Weon;Song, Geun Sung
    • Journal of Korean Neurosurgical Society
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    • 제60권5호
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    • pp.550-559
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    • 2017
  • Objective : Subsidence is a frequent complication of anterior cervical discectomy and fusion. Postoperative segmental micromotion, thought to be a causative factor of subsidence, has been speculated to increase with uncinate process resection area (UPR). To evaluate the effect of UPR on micro-motion, we designed a method to measure UPR area based on pre- and postoperative computed tomography images and analyzed the relationship between UPR and subsidence as a proxy of micro-motion. Methods : We retrospectively collected clinical and radiological data from January 2011 to June 2016. A total of 38 patients (53 segments) were included. All procedures included bilateral UPR and anterior plate fixation. UPR area was evaluated with reformatted coronal computer tomography images. To reduce level-related bias, we converted UPR area to the proportion of UPR to the pre-operative UP area (pUPR). Results : Subsidence occurred in 18 segments (34%) and positively correlated with right-side pUPR, left-side pUPR, and the sum of bilateral pUPR (sum pUPR) (R=0.310, 301, 364; p=0.024, 0.029, 0.007, respectively). Multiple linear regression analysis revealed that subsidence could be estimated with the following formula : $subsidence=1.522+2.7{\times}sum\;pUPR$($R^2=0.133$, p=0.007). Receiver-operating characteristic analysis determined that sum $pUPR{\geq}0.38$ could serve as a threshold for significantly increased risk of subsidence (p=0.005, area under curve=0.737, sensitivity=94%, specificity=51%). This threshold was confirmed by logistic regression analysis for subsidence (p=0.009, odds ratio=8.471). Conclusion : The UPR measurement method confirmed that UPR was correlated with subsidence. Particularly when the sum of pUPR is ${\geq}38%$, the possibility of subsidence increased.

African American Race and Low Income Neighborhoods Decrease Cause Specific Survival of Endometrial Cancer: A SEER Analysis

  • Cheung, Min Rex
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권4호
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    • pp.2567-2570
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    • 2013
  • Background: This study analyzed Surveillance, Epidemiology and End Results (SEER) data to assess if socio-economic factors (SEFs) impact on endometrial cancer survival. Materials and Methods: Endometrial cancer patients treated from 2004-2007 were included in this study. SEER cause specific survival (CSS) data were used as end points. The areas under the receiver operating characteristic (ROC) curve were computed for predictors. Time to event data were analyzed with Kaplan-Meier method. Univariate and multivariate analyses were used to identify independent risk factors. Results: This study included 64,710 patients. The mean follow up time (S.D.) was 28.2 (20.8) months. SEER staging (ROC area of 0.81) was the best pretreatment predictor of CSS. Histology, grade, race/ethnicity and county level family income were also significant pretreatment predictors. African American race and low income neighborhoods decreased the CSS by 20% and 3% respectively at 5 years. Conclusions: This study has found significant endometrial survival disparities due to SEFs. Future studies should focus on eliminating socio-economic barriers to good outcomes.

A Comparative Study of Phishing Websites Classification Based on Classifier Ensemble

  • Tama, Bayu Adhi;Rhee, Kyung-Hyune
    • 한국멀티미디어학회논문지
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    • 제21권5호
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    • pp.617-625
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    • 2018
  • Phishing website has become a crucial concern in cyber security applications. It is performed by fraudulently deceiving users with the aim of obtaining their sensitive information such as bank account information, credit card, username, and password. The threat has led to huge losses to online retailers, e-business platform, financial institutions, and to name but a few. One way to build anti-phishing detection mechanism is to construct classification algorithm based on machine learning techniques. The objective of this paper is to compare different classifier ensemble approaches, i.e. random forest, rotation forest, gradient boosted machine, and extreme gradient boosting against single classifiers, i.e. decision tree, classification and regression tree, and credal decision tree in the case of website phishing. Area under ROC curve (AUC) is employed as a performance metric, whilst statistical tests are used as baseline indicator of significance evaluation among classifiers. The paper contributes the existing literature on making a benchmark of classifier ensembles for web phishing detection.

Mechanical properties of concrete beams reinforced with CFRP prestressed prisms under reverse cyclic loading

  • Liang, Jiongfeng;Yu, Deng;Wang, Jianbao;Yi, Pinghua
    • Earthquakes and Structures
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    • 제11권2호
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    • pp.315-326
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    • 2016
  • This paper presents the results of cyclic loading tests on concrete beams reinforced with various reinforcement, including ordinary steel bars, CFRP bars and CFRP prestressed concrete prisms(PCP). The main variable in the test program was the level of prestress and the cross section of PCP. The seismic performance indexes including hysteretic loops, skeleton curve, ductility, energy dissipation capacity and stiffness degradation were analyzed. The results show that the CFRP prestressed concrete prisms as flexural reinforcement of concrete beams has good seismic performance. And the ductility and the energy dissipation capacity were good, the hysteresis loops were full and had large area.

천연산물로부터 항산화물질의 탐색

  • 김종덕;김민용;배승권;김대현;김학주;김봉조;공재열
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 춘계학술발표대회
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    • pp.596-599
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    • 2000
  • 30 kinds of natural products were considered for developing natural antioxidants by improved D.O. analyzing method including simple calculation of Area Under Curve. Several natural products such as Cimicifuge Rhizoma, Epimedii Herba, Atractylodis Rhizoma Alba, Acori Graminei Rhizoma, Mori Cortex Radicis, Aurantii Nobilis Pericarpium were bore nearly same antioxidant effects compared to synthetic powerful antioxidant BHT and also expressed powerful antioxidant effect than ${\beta}-carotene$ such as Eucommiae Cortex, Cinnamomi Cortex, Angelicae Gigantis Radix, Lycii Furctus, Acanthopanacis Cortex, Sophorae Radix, Paeoniae Radix, Geranii Herba. Another method of DPPH was performed for searching natural antioxidant from natural product. Sophorae Radix, Puerariae Radix, Aurantii Nobilis Pericarpium, Atractylodis Rhizoma Alba, Acori Graminei Rhizoma, Corni Fructus, Angelicae Gigantis Radix, Paeoniae Radix were carried higher antioxidant capacity than ${\beta}-carotene$ by DPPH method.

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가토에서 정맥투여시 생체리듬이 아세부토롤의 약물동태에 미친영향 (The Effect of Circadian Rhythm on the Pharmacokinetics of Acebutolol after Intravenous Administration to Rabbits)

  • 최준식
    • 한국임상약학회지
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    • 제11권2호
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    • pp.57-61
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    • 2001
  • The effect of circadian rhythm on the pharmacokinetics of acebutolol was studied in rabbits administered intravenous 5 mg/kg dose of acebutolol at 09:00 in the morning (a.m) and 22:00 in the evening (p.m). A significant effect of circadian rhythm of pbarmacokinetic parameters as a function of time of day was noted in rabbits, showing lower total body clearance (CLt), higher plasma concentration and the area under the plasma concentration time curve (AUC) when acebutolol was given in the evening. The plasma concentration of acebutolol was increased significantly (p<0.05) at 12-24 hr after dosing in the evening. The AUC was greater in the evening $(111\%)$ than that in the morning and $CL_t$, was higher when acebutolol was given in the morning ($1.12\pm0.24$ ml/hr) versus in the evening ($1.01\pm0.22$ ml/hr), but those were not significant. Therefore, It is reasonable to consider individual circadian rhythm for effective dosage regimen of acebutolol in clinical chronotherapeutics.

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딜티아젬 전처리 가토에서 페니토인의 약물동태학적 연구 (Pharmacokinetics of Phenytoin in Rabbits Pretreated with Diltiazem)

  • 박정미;이진환;최준식;범진필
    • 한국임상약학회지
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    • 제3권2호
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    • pp.139-145
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    • 1993
  • This study was attempted to investigate the pharmacokinetics of phenytoin(4mg/kg iv,) in rabbits pretreated with diltiazem(l and 2.5mg/kg) for 7 days. The plasma concentration and area under the curve(AUC) of phenytoin were increased significantly(p<0.05) in rabbits pretreated with diltiazem(2.5mg/kg) compared with those of control rabbits. Volume of distribution and total body clearance were decreased significantly(p<0,05) in rabbits pretreated with diltiazem compared with those of control rabbits. From the results of this experiment, it is desirable that dosage ragimen of phenytoin should be adjusted and that therapeutic drug monitoring should be practiced for reduction of side or toxic effect when phenytoin will be administered with diltiazem in clinical practice.

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Hypoglycemic Effect of Sargassum ringgoldianum Extract in STZ-induced Diabetic Mice

  • Lee, Chae-Won;Han, Ji-Sook
    • Preventive Nutrition and Food Science
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    • 제17권1호
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    • pp.8-13
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    • 2012
  • This study was designed to investigate whether Sargassum ringgoldianum extract may inhibit ${\alpha}$-glucosidase and ${\alpha}$-amylase activities, and alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. The $IC_{50}$ values of Sargassum ringgoldianum extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.12 mg/mL and 0.18 mg/mL, respectively, which evidenced higher activities than those of acarbose. The blood glucose levels of the Sargassum ringgoldianum extract administered group were significantly lower compared to the control group in the streptozotocin-induced diabetic mice. Moreover, the area under the two-hour blood glucose response curve was significantly reduced and the absorption of dietary carbohydrates was delayed after administration of Sargassum ringgoldianum extract in the diabetic mice. Therefore, these results indicated that Sargassum ringgoldianum extract may help decrease the postprandial blood glucose level via inhibiting ${\alpha}$-glucosidase.