• Title/Summary/Keyword: Hazard ratio

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A Development of Simplified Method for the Detention Pond Design with Runoff Reduction (유출저감용 저류지 설계를 위한 간이기법 개발)

  • Lee, Jae-Joon;Kwak, Chang-Jae;Kim, Ho-Nyun;Lee, Sang-Won
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.632-635
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    • 2007
  • Detention pond has an important role in peak flow reduction to mitigate flood damage. Design of detention pond is accomplished through the preliminary stage, planning stage, and design stage in general. New development projects produce increased peak flow and flow amounts. In this case it is necessary to design the detention pond easily and simply. The simple procedure of detention pond design is proposed in this study. The relevant variables are peak flow ratio ($\alpha$) for the before and after development, and storage ratio which is ratio of storage volume to flow amounts. Simplified method for the detention pond design with runoff reduction is easily used for practical purposes.

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FEM Analysis for the Prediction of Void Closure On the Open Die Forging Process (자유단조공정에서 기공폐쇄 예측을 위한 유한요소해석)

  • Min, K.Y.;Lim, S.J.;Choi, H.J.;Choi, S.;Park, Y.B.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.05a
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    • pp.71-74
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    • 2008
  • In order to resolve the problems which appear after the clean large ingot production process, the impurities which are involved in the steel smelting process should be removed by developing cleaner materials. Through the rationalization of cogging process that is the first forging process of large ingot the quality is to be improved. For the sake of the optimization of an open die forging process and the improvement of the subject matter frequency ratio, a hazard precise die forging process must be developed and a Near Net Shape Forming accomplished. As a result, energy can be reduced by minimizing an after control process. In order to produce large axes and other forming parts, processing techniques are to be developed. In this context, this paper is a study about a reduction ratio, dies width ratio and rotary angles, the amount of overlap, and intends to analysis cogging processes, utilizing Deform-3D cogging module

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Odds ratio of major risk factors associated with delirium by Bayesian network (베이지안 네트워크를 활용한 정신장애 질병 섬망의 주요 위험인자와 오즈비)

  • Lee, Jea-Young;Choi, Young-Jin
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.2
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    • pp.217-225
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    • 2011
  • It is important to find risk factors associated with mental disorder. Also the hazard ratio that represent the relationship of risk factors with illness is main interest in medicine. Thus we used odds ratio to explore the relationship between mental disorder and risk factors. On this paper, when we applied Bayesian network to delirium of mental disorder, we selected major risk factors and calculated odds ratio. Especially we identified odds ratio of single risk factors and multiple risk factors.

Black Hispanic and Black Non-Hispanic Breast Cancer Survival Data Analysis with Half-normal Model Application

  • Khan, Hafiz Mohammad Rafiqullah;Saxena, Anshul;Vera, Veronica;Abdool-Ghany, Faheema;Gabbidon, Kemesha;Perea, Nancy;Stewart, Tiffanie Shauna-Jeanne;Ramamoorthy, Venkataraghavan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9453-9458
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    • 2014
  • Background: Breast cancer is the second leading cause of cancer death for women in the United States. Differences in survival of breast cancer have been noted among racial and ethnic groups, but the reasons for these disparities remain unclear. This study presents the characteristics and the survival curve of two racial and ethnic groups and evaluates the effects of race on survival times by measuring the lifetime data-based half-normal model. Materials and Methods: The distributions among racial and ethnic groups are compared using female breast cancer patients from nine states in the country all taken from the National Cancer Institute's Surveillance, Epidemiology, and End Results cancer registry. The main end points observed are: age at diagnosis, survival time in months, and marital status. The right skewed half-normal statistical probability model is used to show the differences in the survival times between black Hispanic (BH) and black non-Hispanic (BNH) female breast cancer patients. The Kaplan-Meier and Cox proportional hazard ratio are used to estimate and compare the relative risk of death in two minority groups, BH and BNH. Results: A probability random sample method was used to select representative samples from BNH and BH female breast cancer patients, who were diagnosed during the years of 1973-2009 in the United States. The sample contained 1,000 BNH and 298 BH female breast cancer patients. The median age at diagnosis was 57.75 years among BNH and 54.11 years among BH. The results of the half-normal model showed that the survival times formed positive skewed models with higher variability in BNH compared with BH. The Kaplan-Meir estimate was used to plot the survival curves for cancer patients; this test was positively skewed. The Kaplan-Meier and Cox proportional hazard ratio for survival analysis showed that BNH had a significantly longer survival time as compared to BH which is consistent with the results of the half-normal model. Conclusions: The findings with the proposed model strategy will assist in the healthcare field to measure future outcomes for BH and BNH, given their past history and conditions. These findings may provide an enhanced and improved outlook for the diagnosis and treatment of breast cancer patients in the United States.

Pyogenic Liver Abscess as a Warning Sign for Primary Liver Cancer: A Nationwide Population-based Study

  • Huang, Wen-Kuan;Lin, Yung-Chang;Chiou, Meng-Jiun;Yang, Tsai-Sheng;Chang, John Wen-Cheng;Yu, Kuang-Hui;Kuo, Chang-Fu;See, Lai-Chu
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4727-4731
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    • 2013
  • Background: There have been no large-scale population-based studies to estimate the subsequent risk of primary liver cancer (PLC) among patients with pyogenic liver abscess (PLA). This study aimed to provide relevant data. Materials and Methods: The Taiwan Longitudinal Health Insurance Database for the years 2000 and 2005 was used. The PLA group were adult inpatients who were newly diagnosed with PLA from 2000 to 2008. The control group was randomly selected and matched with the PLA group in terms of age, sex, and date in which medical treatment was sought other than for PLA. Results: There were 1,987 patients each in the PLA and control groups. In total, 56 had PLC, 48 (2.4%, 601.5 per 100,000 person-years) from the PLA group, and 8 from the control group. After adjusting for potential covariates, the hazard ratio of PLC for the PLA group was 3.4 times that of the control group (95% confidence interval = 1.6-7.3, p <0.001). The PLC risk for the PLA group was significantly higher within the first year after PLA diagnosis (hazard ratio: 35.4) as compared with the control group and became insignificant (hazard ratio: 2.0, 95% confidence interval = 0.8-4.9) more than one year after PLA diagnosis. Conclusions: Patients with PLA have a higher rate of PLC than matched controls, especially within the first year after the diagnosis of PLA, suggesting PLA is a warning sign for PLC.

Comparative analysis of forest fire danger rating on the forest characteristics of thinning area and non-thinning area on forest fire burnt area (산불피해지역에서 숲 가꾸기 실행유무가 산불에 미치는 영향)

  • Lee, Si-Young;Lee, Myung-Woog;Yeom, Chan-Ho;Kwon, Chun-Geun
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.153-156
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    • 2008
  • Comparative analysis of forest fire danger rating on the forest characteristics of thinning area and non-thinning area on forest fire burnt area was studied in this work. To investigate the effect of thinning slash in forest fire, Gangneung-si Wangsan-myeon, Ulgin-gun Wonnam-Myeon, Samchok-si Gagok-Myeon, in which forest fire broke out, were selected. As a result that investigated forest fire danger ratio between thinning slash and non-thinning slash, leeward scorching ratio(36%), crown damage ratio(29%), mortality of branch at the former are higher than those at the latter, leeward scorching ratio of tree, where thinning slash is around, is 10%-20% higher than that of independent tree. So I estimate that thinning slash has a some effect on the intensity of forest fire. And the result to investigate damage of forest fire according to tree species shows that leeward scorching ratio of conifer is 5% higher than that of non-conifer, and mortality of branch of the former is 19% higher than that of the latter. It is considered that forest fire may affect directly to a tree trunk if it diffuse to piled thinning tree because there was no space between thinning trees and trees. Furthermore, it was found that re-ignition had a chance to occur due to lots of piled thinning trees.

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Novel cystography parameter to predict early recovery from urinary continence after radical prostatectomy for prostate cancer: a retrospective study

  • Yeong Uk Kim
    • Journal of Yeungnam Medical Science
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    • v.40 no.3
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    • pp.252-258
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    • 2023
  • Background: The purpose of this study was to investigate whether postoperative cystography findings can predict early and longterm recovery from incontinence after radical prostatectomy (RP), compared with the other cystography parameters. Methods: I retrospectively reviewed 118 patients who underwent robot-assisted RP (RARP) for localized prostate cancer at single institution between January 2016 and April 2021. One hundred and seven patients were included in the study. Postoperative cystography was routinely performed 7 days after surgery. The bladder neck to pubic symphysis ratio, vesicourethral angle, and bladder neck anteroposterior length (BNAP) ratio (the bladder neck-posterior margin distances divided by the anteroposterior lengths) were evaluated. Continence was defined as cessation of pad use. The association between these variables and urinary incontinence was also analyzed. Results: The urinary incontinence recovery rates 1, 3, 6, and 12 months after RARP were 43.92%, 66.35%, 87.85%, and 97.19%, respectively. Multivariate logistic regression analysis demonstrated that a lower BNAP ratio and wider vesicourethral angle were significantly associated with continence restoration at 1, 3, and 6 months after surgery. In addition, in terms of days of pad usage, lower BNAP ratio, wider vesicourethral angle, and bladder neck preservation were significantly associated with recovery from urinary incontinence within 12 months as assessed by Cox proportional hazard analysis. Conclusion: This study demonstrated that vesicourethral angle and BNAP ratio were independent predictors of early recovery from post-prostatectomy incontinence. I suggest that both the sagittal and coronal views of postoperative cystography help anticipate early continence restoration after RARP.

Pathogens and Prognotic Factors for Early Onset Sepsis in Very Low Birth Weight Infants (극소 저체중 출생아에서 조기 패혈증의 원인균과 예후인자)

  • Kim, Yi-Sun;Kim, Jin-Kyu;Yoo, Hye-Soo;Ahn, So-Yoon;Seo, Hyun-Ju;Choi, Seo-Heui;Park, Soo-Kyung;Jung, Yu-Jin;Kim, Myo-Jing;Jeon, Ga-Won;Koo, Soo-Hyun;Lee, Kyung-Hoon;Chang, Yun-Sil;Park, Won-Soon
    • Neonatal Medicine
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    • v.16 no.2
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    • pp.163-171
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    • 2009
  • Purpose: This study was conducted to determine the incidence, causative pathogens, risk factors and mortality for early onset sepsis in the first three days in very low birth weight infants. Methods: The medical records of 1,124 very low birth weight infants admitted to the neonatal intensive care unit of Samsung Medical Center between November 1994 and December 2008 were retrospectively reviewed. The incidence, causative pathogens, risk factors, and mortality for early onset sepsis in the first 3 days of life in very low birth weight infants were evaluated. Results: Early onset sepsis, as confirmed by positive blood cultures, was present in 17 of 1,124 infants (1.5%). Sixty-four percent of the isolated pathogens were gram-positive bacteria and 35% of the isolated pathogens were gram-negative bacteria. The dominant pathogens of early onset sepsis included Staphylococcus aureus (23.5%), Esherichia coli (23.5%), and Enterococcus (17.6%). Vaginal delivery (adjusted odds ratio [OR], 3.7; 95% confidence interval [CI], 1.3-10.3; P=0.01) was associated with early onset sepsis. The overall mortality (adjusted hazard ratio, 3.0; 95% CI, 1.4-6.5; adjusted P=0.0039) and mortality within 72 hours of life (adjusted hazard ratio, 6.5; 95% CI, 2.2-18.9; adjusted P=0.0005) of infants with early onset sepsis were higher than that of uninfected infants. Conclusion: Early onset sepsis remains an uncommon, but potentially lethal problem among very low birth weight infants. Knowledge of the likely causative organisms and risk factors for early onset sepsis can aid in instituting prompt and appropriate therapy, in order to minimize mortality.

Analysis of Flood Characteristics at Confluence by Lateral Inflow (횡유입에 의한 합류부 홍수특성 분석)

  • Choi, Hung-Sik;Cho, Min-Suk;Park, Young-Seop
    • Journal of the Korean Society of Hazard Mitigation
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    • v.6 no.1 s.20
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    • pp.59-68
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    • 2006
  • Flow separation of recirculation zone by increasing of flow and change of its direction at confluence results in backwater due to conveyance reduction. The hydraulic characteristics of flow separation are analysed by experimental results of flow ratios of tributary and main streams and approaching angles. The boundary of flow separation by dimensionless length and width is defined by the streamline of zero and this definition agrees well to the existing investigation. Because flow separation doesn't appear in small flow ratio and approaching angle of $30^{\circ}$, the equation of flow separation with flow ratio and approaching angle is provided. In flow separation consideration and comparing with previous results, the existing equations of dimensionless length and width ratios by function of approaching angle, flow ratio, and downstream Froude number are modified and also contraction coefficient and shape factor are analysed. Dimensionless length and width ratios are proportional to the flow ratio and approaching angle. In analysis of water surface profiles, the backwater effects are proportional to the flow ratio and approaching angle and the magnitude at outside wall is greater than that of inside wall of main stream. The length, $X_l$ from the beginning of confluence to downstream of uniform flow, where the depth is equal to uniform depth, is characterized by width of stream, flow ratio, approaching angle, and contraction coefficient. The ratios between maximum water depth by backwater and minimum depth at separation are analysed.

An Experimental Study of Fatigue and Static Behavior for Composite Deck Member (복합재료 바닥판 부재의 정적 및 피로거동에 관한 실험적 연구)

  • Kim, Young-Chan;Park, Tai-Young;Kim, Doo-Hwan
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.479-482
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    • 2007
  • For making an application in construction parts of the composite material's complicated theory needs to accumulation of data by the help of study and experiment(demonstrate). Thus, this study is conducted research and analysis about the Influence of repeated loading cycles on Strength Ratio of the high quality material which is Carbon/Epoxy Composite Laminates through the test of tensile and fatigue Characteristics, based on it, construction engineers will can apply composite materials to construction technical without difficulty.

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