• 제목/요약/키워드: A case control study

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Intelligent cooling control for mass concrete relating to spiral case structure

  • Ning, Zeyu;Lin, Peng;Ouyang, Jianshu;Yang, Zongli;He, Mingwu;Ma, Fangping
    • Advances in concrete construction
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    • 제14권1호
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    • pp.57-70
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    • 2022
  • The spiral case concrete (SCC) used in the underground powerhouse of large hydropower stations is complex, difficult to pour, and has high requirements for temperature control and crack prevention. In this study, based on the closed-loop control theory of "multi-source sensing, real analysis, and intelligent control", a new intelligent cooling control system (ICCS) suitable for the SCC is developed and is further applied to the Wudongde large-scale underground powerhouse. By employing the site monitoring data, numerical simulation, and field investigation, the temperature control quality of the SCC is evaluated. The results show that the target temperature control curve can be accurately tracked, and the temperature control indicators such as the maximum temperature can meet the design requirements by adopting the ICCS. Moreover, the numerical results and site investigation indicate that a safety factor of the spiral case structure was sure, and no cracking was found in the concrete blocks, by which the effectiveness of the system for improving the quality of temperature control of the SCC is verified. Finally, an intelligent cooling control procedure suitable for the SCC is proposed, which can provide a reference for improving the design and construction level for similar projects.

청소년 고혈압 관련 유전자의 연관성 분석: Kangwha Study (Association Analysis of the Essential Hypertension Susceptibility Genes in Adolescents: Kangwha Study)

  • 서일;남정모;김성주;신동직;허남욱;강대룡
    • Journal of Preventive Medicine and Public Health
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    • 제39권2호
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    • pp.177-183
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    • 2006
  • Objectives : In this study we examined the association between the genetic markers ACE (A-240T, C-93T, I/D, A2350G), AGT (M235T), AT1R (A1166C), CYP11B2 (T344C, V386A), REN (G2646A), ADRB2 (G46A, C79G, T47C, T1641), GNB3 (C825T) and ADD1 (G460W) and the presence of essential hypertension in adolescents. Methods : The Kangwha Study is an 18-year prospective study that is aimed at elucidating the determinants of the blood pressure level from childhood to early adulthood. For this study, we constructed a case-control dataset of size of 277 and 40 family trios data from the Kangwha Study. For this purpose, we perform a single locus-based case-control association study and a single locus-based TDT (transmission/disequilibrium test) study. Results : In the case-control study, the single locus-based association study indicated that the ADD1 (G460W) (p=0.0403), AGT (M235T) (p=0.0002), and REN (G2646A) (p=0.0101) markers were significantly associated with the risk of hypertension. These results were not confirmed on the TDT study. This study showed that genetic polymorphisms of the ADD1, AGT and REN genes might be related to the hypertension in Korean adolescents. Conclusions : This study provided useful information on genetics markers related to blood pressure. Further study will be needed to confirm the effect of the alpha adducin gene, the angiotensinogen gene and the renin gene on essential hypertension.

산업재해 예방정책에 대한 평가모형 (Assessment Model for Industrial Accidents Prevention Policy)

  • 김영선;조진남;백재욱
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제17권1호
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    • pp.38-49
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    • 2017
  • Purpose: The purpose of this study is to introduce the assessment model for industrial accidents prevention policy. Methods: 10 years of industrial accidents data are explored through EDA approach. Case control study is tried in order to assess the effectiveness of the measures taken by Korea Safety and Health Agency, Civilian, and 'Ministry of Employment and Labor'. Propensity score matching is used to match the characteristics of the two groups compared, and then case control study is again conducted. Next, logistic and Poisson regressions are used to assess the risk factors. Results: According to case control study involvement of 'Korea Safety and Health Agency' and 'Ministry of Employment and Labor' were not effective, but Civilian was. Propensity score matching leads to the same conclusion. Poisson regression reveals the impact of the risk factors on the industrial accidents. Industrial accidents occur more often as the number of employees grows. Mining, farming, fishing, 'transportation storage and telecommunication' and forestry have a higher level of industrial accidents but service industry has a lower level. It is odd that more involvement of Korea Safety and Health Agency, Civilian, and Ministry of Employment and Labor means more industrial accidents. Conclusion: 'Korea Safety and Health Agency', Civilian, and 'Ministry of Employment and Labor' seem to visit those industries with more industrial accidents.

참여 중심 어린이 교통안전교육 프로그램 효과 평가 (The Effectiveness of a Participatory Road Traffic Safety Education Program for the Elementary School Students)

  • 손주현;이명선
    • 보건교육건강증진학회지
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    • 제27권1호
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    • pp.49-60
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    • 2010
  • Objectives: The purpose was to evaluate the effectiveness of participatory road safety education program for the lower grade in elementary schools. This program was developed based on the Activated Health Education model. Methods: Study design was compromise experimental group pre-post design. 456 students in 8 schools were nonrandomly assigned to study group(n=224) or control(n=232). The students finished self-administered questionnaire before and after education. Collected data was analyzed by using the SPSS. Results: 1. The common relevant factors in road safety knowledge and attitude were 'residential state' and 'experience of traffic accident'. 2. The knowledge showed that the case and control scored at 6.48 and 6.41 points before. After this intervention, the case and control scored at 8.38 and 6.51. The difference of the case was significant(p<0.001). 3. The attitude showed that the case and control scored at 19.67 and 19.63 before. After this, the case and control scored at 19.86 and 19.63. The difference of the case was significant(p<0.05). Conclusion: In order to implement the road safety education, children's socio-demographic characteristics were considered. Because this education was effective in both improving knowledge and attitude and bringing interest, various participatory program will be applied in road safety education for children.

Colorectal Cancer and its Association with the Metabolic Syndrome: a Malaysian Multi-Centric Case-Control Study

  • Ulaganathan, V.;Kandiah, M.;Zalilah, M.S.;Faizal, J.A.;Fijeraid, H.;Normayah, K.;Gooi, B.H.;Othman, R.
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권8호
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    • pp.3873-3877
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    • 2012
  • Objective: Colorectal cancer (CRC) and the metabolic syndrome (MetS) are both on the rise in Malaysia. A multi-centric case-control study was conducted from December 2009 to January 2011 to determine any relationship between the two. Methods: Patients with confirmed CRC based on colonoscopy findings and cancer free controls from five local hospitals were assessed for MetS according to the International Diabetes Federation (IDF) definition. Each index case was matched for age, gender and ethnicity with two controls (140: 280). Results: MetS among cases was highly prevalent (70.7%), especially among women (68.7%). MetS as an entity increased CRC risk by almost three fold independently (OR=2.61, 95%CI=1.53-4.47). In men MetS increased the risk of CRC by two fold (OR=2.01, 95%CI, 1.43-4.56), demonstrating an increasing trend in risk with the number of Mets components observed. Conclusion: This study provides evidence fora positive association between the metabolic syndrome and colorectal cancer. A prospective study on the Malaysian population is a high priority to confirm these findings.

공단지역의 대기배출시설을 대상으로 한 악취성분의 처리효율에 관한 연구 - 반월공단 지역을 중심으로 (A Study of Control Efficiency for Odorous Pollutants in Various Emission Control Units in the Ban-Wall Industrial Complex)

  • 최여진;전의찬;김기현
    • 한국대기환경학회지
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    • 제23권1호
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    • pp.110-124
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    • 2007
  • In this study, the control efficiency of odorous compounds was measured from diverse control process units of 14 individual companies located within the Ban-Wall industrial complex of Ansan city, Korea (January to July 2005), To quantify the control efficiency levels of major odorous compounds, we collected odor samples from both the front and rear side of 17 control process units ($N=17{\times}2=34$). If the control efficiency is compared for each of 32 compounds between different process units, wet scrubber (WS) was found to be the most effective unit in terms of the sum of pollutants showing the positive control signals. Although the WS system shows generally a good control pattern for VOC, it is not the case for most index odorous pollutants; only 3 out of 12 index compounds were found to show positive control efficiencies. The results of the study also indicated that the control efficiency differ greatly between different industrial sectors and/or control process types. In the case of leather industry, carbonyl compounds were found to exhibit the highest control efficiency with its values varying from 19 to 90%. On the other hand, in the case of metal production sector, VOC recorded the maximum control efficiency with values varying from 18 to 79%. According to this study, most air pollution control facilities operated in most companies show fairly poor control efficiencies for most malodor compounds. Hence, to obtain best control efficiency of odorous pollutant emission, acquisition of better information on source characteristics and establishment of effective control technologies are highly demanding.

Control Variables of Remote Joint Analysis Realization on the M2M Case

  • Lim, Sung-Ryel;Choi, Bo-Yun;Lee, Hong-Chul
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제6권1호
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    • pp.98-115
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    • 2012
  • New trend called ubiquitous leads the recent business by standardization and integration. It should be the main issue how to guarantee the integration and accountability on each business, especially in mission critical system which is mainly supported by M2M (Machine to Machine) control mechanism. This study is from the analysis of digital forensics case study that is from the M2M Sensing Control Mechanism problem of the "Imjin River" case in 2009, where a group of family is swept away to death by water due to M2M control error. The ubiquitous surroundings bring the changes in the field of criminal investigation to real time controls such as M2M systems. The needs of digital forensics on M2M control are increasing on every crime scene but we suffer from the lack of control metrics to get this done efficiently. The court asks for more accurately analyzed results accounting high quality product development design. Investigators in the crime scene need real-time analysis against the crime caused by poor quality of mission critical systems. It seems to be every need of Real-Time-Enterprise, so called ubiquitous society on the case. We try to find the efficiency and productivity in discovering non-functional design defects in M2M convergence products focusing on three metrics in study model with quick implementation. Digital forensics system in present status depends on know-how of each investigator and is hard to expect professional analysis on every field. This study set up a hypothesis "Co-working of professional investigators on each field will qualify Performance and Integrity" especially in mission critical system such as M2M and suggests "Online co-work analysis model" to efficiently detect and prevent mission critical errors in advance. At the conclusion, this study proved the statistical research that was surveyed by digital forensics specialists around M2M crime scene cases with quick implementation of dash board.

Stressful Life Events and Risk of Colorectal Cancer: A Case-Control Study of Iran

  • Azizi, Hosein;Esmaeili, Elham Davtalab
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권6호
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    • pp.2403-2407
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    • 2015
  • Background: Very few analytical studies are available on any association between stressful life events (SLE) and colorectal cancer (CRC), at least in Iran. The aim of this case control study was to determine the association between stressful life events (SLE) and colorectal cancer. Materials and Methods: This study was conducted in four hospital colonoscopy units in Tabriz city of Iran including 414 participants aged 40-75 years: 207 cases with CRC confirmed by pathology and colonoscopy findings and 207 controls free of neoplastic conditions were selected (from the same hospitals at the same period for the cases and after matching for age and sex). Stressful life events were assessed using a 43-item Holmes and Rahe Life Events Questionnaire. Multivariate logistic regression was used to estimate adjusted odds ratios for SLE and risk of CRC. Results: The stressful life event mean score in the case group was 141.3, in contrast to 63.8 in the control group (p<0.011). After adjusting for confounders, death of dear ones increased the risk of CRC (OR: 2.49; 95%CI: 1.41-5.13). Other types of stressful life events (family and husband disputes, serious occupational problems, unemployment of > 6 months, and Serious financial problems) were also associated with CRC, but without statistical significance. Conclusions: According to our findings, it seems that SLE may increase the risk of CRC.

2단계 사례-대조자료를 위한 로지스틱 회귀모형의 추론 (Estimation of Logistic Regression for Two-Stage Case-Control Data)

  • 신미영;신은순
    • 응용통계연구
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    • 제13권2호
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    • pp.237-245
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    • 2000
  • 이 논문에서는 2단계 계획 하에서의 사례-대조 자료를 로지스틱 회귀 모형에 적합시키고 WESML방법으로 모수를 추정하며 추정량의 점근분포를 찾는다. 또한 WESML,방법과 CML 방법으로 얻은 모수의 추정량과 표준오차를 실제 자료를 이용하여 비교한다.

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Risk Factors of Breast Cancer in Kyzylorda Oblast of Kazakhstan: a Case-Control Study

  • Toleutay, Ulpan;Reznik, Vitaly;Kalmatayeva, Zhanna;Smigelskas, Kastytis
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권10호
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    • pp.5961-5964
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    • 2013
  • Background: Breast cancer in Kazakhstan and its Kyzylorda oblast is the most prevalent cancer in women and features increasing trends of incidence. The aim of study was to reveal risk factors for breast cancer among women of Kyzylorda oblast of Kazakhstan. Materials and Methods: A hospital-based case-control study was conducted at Kyzylorda oblast Oncology Center, including 114 cases of breast cancer and 196 controls. Binary logistic regression analysis was performed. Results: Social and behavioral risk factors for breast cancer were evaluated, among which unfavorable living conditions, chronic stress, unilateral breastfeeding, breastfeeding less than 3 months and over 2 years, abortions, and hereditary predisposition were found to be related with increased breast cancer risk. Breastfeeding for 6-24 months was found to be protective. Conclusions: The findings may have significant impact on activity planning aimed towards breast cancer reduction among women in Kazakhstan.