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검색결과 539건 처리시간 0.031초

치과기공사의 업무스트레스에 관한 연구 (A Study on the Work Stress of Dental Technicians)

  • 권은자;김지환
    • 대한치과기공학회지
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    • 제23권2호
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    • pp.105-119
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    • 2002
  • This study was designed to grasp the degree of job stress affecting dental technicians and the degree of the symptoms of their job stress. With this in mind, the researcher selected a total of 170 dental technicians living in Seoul and Incheon, conducting a research in a period ranging from August 1,2001, to August 20, 2001. The researcher made use of a structured questionnaire whose reliability and feasibility are proved. The questionnaire is composed of a total of 55 questions: thirteen questions related to the subjects' general characteristics; 28 questions connected to the measurement of job stress and fourteen questions linked with the measurement of job-stress symptoms. The researcher analyzed the findings with the aid of SPSS(Statistical Package for Social Sciences). The research came to draw the following conclusions on the basis of frequency, percentage, T-test, and F-test, multiple regression. I. The analysis into the job stress of the subjects indicates that there is a significant difference in difficult questions among their work places, working hours, academic background, job satisfaction and jobs(P<.05). The job stress stands at 3.48 on the average, and the area of conflict among too much work and job performance turns out to be highly perceived. 2. The analysis into the degree of the symptoms of the job stress of the subjects shows that there is a significant difference in work place, working hours, job satisfaction and the continual maintenance of job(P<.05). The symptoms of job stress accounts for 2.65 on the average. Physical symptoms turn out to be highly perceived; The response 'My arms and legs are killing me' proves to stand for 3.03. 3. The correlation between job stress and the symptoms of job stress turns out to be significant(r=0.519, P<0.001), and there is a significant correlation between the average points of each job-stress area and the average points of the symptoms of job stress. All in all, it is necessary that dental technicians themselves should make positive efforts to control and relieve stress and that more efficient programs should be implemented with a view to dealing with stress.

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일부 고등학생들의 학교보건교육이 건강증진행위에 미치는 영향 (The Effects of School Health Education on Health Promotion Behavior Among Selected High School Students)

  • 이창국;이명선;서승희;한성현
    • 보건교육건강증진학회지
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    • 제22권1호
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    • pp.17-40
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    • 2005
  • This study was aimed to analyze the status of the a health education and the health behavior, and to identify the effected factors of health promotion behavior based on Green's PRECEDE Model among high school students The data was collected by interview survey with self-administration questionnaire from the selected high school students during the end of the second semester, 2001, and 1,591 students are analyzed. The statistical method of the analysing for effected factors of health promotion behavior was used the Multiple Linear Regression Analysis by SPSS package program. The results of this study are as fellows. 1. The index of the health educational contents shows the 18.14 points per 86 points, 18.96 points in girl students, 17.53 points in boy students. 2. In the index of health promotion behaviors was 84.9 points per 140 full points in all average; 61 points per 100 points. The experienced rate of smoking was $35\%$ of all students, $38.5\%$ of boy students, $30.6\%$ of girl students each. The experienced rate of drinking was $62.2\%$ of all students, $61.6\%$ of boy students, $69.4\%$ of girl students. 3. The effected factors of the health promotions behaviors to analyse by multiple linear regression model was sports activity, the degree of satisfaction of their school life, the academic records of school, the present health conditions, their awareness for hazard of smoking for their health, the experiences of the smoking, their stresses(R$^2$ =0.174). and the factors as the experiences of drinking, their stresses, and the indexes for the health education contents in their school were added in girls students.

한국 성인 남성의 피부색 분류와 선호색에 대한 연구 (Clustering of Skin Colors on Korean Adult Males and Their Preference Colors)

  • 김구자
    • 한국의류학회지
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    • 제27권11호
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    • pp.1338-1349
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    • 2003
  • The color of apparels has the close interdependency on the skin colors of the wearers. This study was carried out to group the skin colors of Korean males into several similar skin colors and to analyze their preference colors. The skin colors were measured quantitatively and classified into several clusters that has similar hue, value and chroma with Munsell color system that is internationally used to communicate the colors. Sample size was 420 Korean males. With color spectrometer, JX-777, 4 points of the body were measured. All subjects had been shown with 40 color chips and answered their preference colors. Data were analysed by K-means Cluster analysis, Duncan test, Frequency and Chi square test using SPSS WIN 10 statistical package. Findings were as follows: 1. The skin colors of Korean males were mixed with skin colors of YR, R, and Y. 2. 420 subjects who have YR color were clustered in 3 kinds of skin color groups. 3. The average face color of total subjects was 4.81YR 5.91/4.97 in Munsell color system, 60.74 in L value, 13.71 in a value, 24.54 in b value. 136 observations out of 420 subjects were composed of Type 1: 4.50YR 6.35/4.87 and 192 observations were composed of Type 2: 4.62YR 5.86/5.12 and 92 observations were composed of Type 3: 5.67YR 5.37/4.79. 4. The average skin color of total 420 subjects was 6.26YR 6.07/4.41 and 62.33 in L value, 10.64 in a value, 23.48 in b value. The average skin color of Type 1 was 6.27YR 6.44/4.27 and of Type 2 was 6.15YR 5.91/4.49 and of Type 3 was 6.49YR 5.84/4.43 respectively. 5. 3 groups showed that the most preference color of sport$.$casual was 2.5Y 8/16 and 7.5PB 4/16 and the most preference color to their skins was 7.5PB 4/16 and 7.5YR 7/16.

무연솔더 접합부의 미세조직 특성 (Microstructural Charicteristics of Pb-free Solder Joints)

  • 유아미;장재원;김목순;이종현;김준기
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2010년도 춘계학술발표대회 초록집
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    • pp.82-82
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    • 2010
  • 표면실장 공법을 통해 CSP 패키지를 보드에 실장 하는데 있어 무연솔더 접합부의 신뢰성에 영향을 미치는 인자 중 가장 중요한 것은 접합부에 형성되는 IMC (Intermetallic compound, 금속간화합물)인 것으로 알려져 있다. 접합부의 칩 부분에는 솔더와 칩의 UBM (Under bump metalization)이 접합하여 IMC가 형성되나, 보드 부분에는 솔더와 보드의 UBM 뿐만 아니라 그 사이에 솔더 페이스트가 함께 접합되어 IMC가 형성된다. 본 연구에서는 패키지의 신뢰성 연구를 위해 솔더 페이스트의 유무 및 두께에 따른 무연 솔더 접합부의 미세조직의 변화를 분석하였다. 본 실험에서는 Sn-3.0(Wt.%)Ag-0.5Cu 조성과 본 연구진에 의해 개발된 Sn-Ag-Cu-In 조성의 직경 $450{\mu}m$ 솔더 볼을 사용하였으며, 솔더 페이스트는 상용 Sn-3.0Ag-0.5Cu (ALPHA OM-325)를 사용하였다. 칩은 ENIG (Electroless nickel immersion gold) finish pad가 형성된 CSP (Chip scale package)를, 보드는 OSP (Organic solderability preservative)/Cu finish pad가 형성된 것을 사용하였다. 실험 방법은 보드를 솔더 페이스트 없이 플라즈마 처리 한 것, 솔더 페이스트를 $30{\mu}m$ 두께로 인쇄한 것, $120{\mu}m$의 두께로 인쇄한 것, 이렇게 3가지 조건으로 준비한 후, 솔더 볼이 bumping된 칩을 mounting하여, $242^{\circ}C$의 peak 온도 조건의 oven(1809UL, Heller)에서 reflow를 실시하여 패키지를 형성하였다. 이후 시편은 정밀 연마한 후, OM(Optical Microscopic)과 SEM(scanning electron microscope) 및 EDS(energy dispersive spectroscope)를 사용하여 솔더 접합부 IMC의 미세조직을 관찰, 분석하였다.

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불완전한 관측틈을 가진 재발 사건 소요시간에 대한 자료 분석 (Statistical analysis of recurrent gap time events with incomplete observation gaps)

  • 신슬비;김양진
    • Journal of the Korean Data and Information Science Society
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    • 제25권2호
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    • pp.327-336
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    • 2014
  • 재발 사건 자료란 연구대상이 같은 종류의 사건을 반복적으로 경험할 때 발생하는 자료이다. 이러한 재발 사건은 사회과학, 자연과학, 공학, 의약학 등 다양한 분야에서 나타날 수 있다. 재발 사건자료를 분석할 때 연구자의 관심에 따라 사건 발생시간이나 사건 발생간의 소요시간을 이용하여 분석할 수 있다. 이 논문에서는 사건 발생시점간의 소요시간을 이용하여 불완전한 관측을 가진 재발 사건자료를 분석하고자 한다. 이 자료의 특징은 일부 관측대상들이 일정기간 동안 연구에서 제외되는 관측틈을 갖는다는 것이다. 이 때 관측틈은 불완전한 형태로 나타나게 되는데 그 이유는 관측틈의 시작시점은 알고 있지만 종료시점은 알 수 없기 때문이다. 이러한 미지의 종료시점을 추정하기 위해서 구간 중도 절단 방법이 적용된다. 따라서 종료시점이 추정된 후 프레일티를 포함한 회귀모형을 적용하여 공변량이 사건 재발에 미치는 영향을 알아볼 수 있다. 또한 제안한 방법을 실제자료에 적용하여 관측틈을 고려한 경우와 고려하지 않은 경우를 비교하고자 한다.

Bayesian Survival Analysis of High-Dimensional Microarray Data for Mantle Cell Lymphoma Patients

  • Moslemi, Azam;Mahjub, Hossein;Saidijam, Massoud;Poorolajal, Jalal;Soltanian, Ali Reza
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권1호
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    • pp.95-100
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    • 2016
  • Background: Survival time of lymphoma patients can be estimated with the help of microarray technology. In this study, with the use of iterative Bayesian Model Averaging (BMA) method, survival time of Mantle Cell Lymphoma patients (MCL) was estimated and in reference to the findings, patients were divided into two high-risk and low-risk groups. Materials and Methods: In this study, gene expression data of MCL patients were used in order to select a subset of genes for survival analysis with microarray data, using the iterative BMA method. To evaluate the performance of the method, patients were divided into high-risk and low-risk based on their scores. Performance prediction was investigated using the log-rank test. The bioconductor package "iterativeBMAsurv" was applied with R statistical software for classification and survival analysis. Results: In this study, 25 genes associated with survival for MCL patients were identified across 132 selected models. The maximum likelihood estimate coefficients of the selected genes and the posterior probabilities of the selected models were obtained from training data. Using this method, patients could be separated into high-risk and low-risk groups with high significance (p<0.001). Conclusions: The iterative BMA algorithm has high precision and ability for survival analysis. This method is capable of identifying a few predictive variables associated with survival, among many variables in a set of microarray data. Therefore, it can be used as a low-cost diagnostic tool in clinical research.

Application of Bayesian Multilevel Space-Time Models to Study Relative Risk of Esophageal Cancer in Iran 2005-2007 at a County Level

  • Rastaghi, Sedigheh;Jafari-Koshki, Tohid;Mahaki, Behzad
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권14호
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    • pp.5787-5792
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    • 2015
  • Background: Reported age standardized incidence rates for esophageal cancer in Iran are 0.88 and 6.15 for females and males, at fifth and the eighth ranks, respectively, of cancers overall. The present study aimed to map relative risk using more realistic and less problematic methods than common estimators. Materials and Methods: In this ecological investigation, the studied population consisted of all esophageal cancer patients in Iran from 2005 to 2007. The Bayesian multilevel space-time model with three levels of county, province, and time was used to measure the relative risk of esophageal cancer. Analyses were conducted using R package INLA. Results: The total number of registered patients was 7,160. According to the results, the three-level model with adjustment for risk factors of physical activity and smoking had the best fit among all models. The overall temporal trend was significantly increasing. At county level, Ahar, Marand, Salmas, Bojnoord, Saghez, Sarakhs, Shahroud and Torbatejam had the highest relative risks. Physical activity was found to have significant direct association with risk of developing esophageal cancer. Conclusions: Given to great variation across geographical areas, many different factors affect the incidence of esophageal cancer. Conducting further studies at the individual level in areas with high incidence could provide more detailed information on risk factors of esophageal cancer.

Ro-Ro 구역용 미분무 소화설비의 개발을 위한 실험적 연구 (An experimental study on development of water mist fire-fighting systems for Ro-Ro spaces)

  • 곽지현;김영한
    • Journal of Advanced Marine Engineering and Technology
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    • 제37권8호
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    • pp.946-952
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    • 2013
  • 선박의 Ro-Ro 구역이나 특별범주구역의 화재방호를 위해 설치하는 고정식 수계소화설비의 개발 및 실용화를 위해, 특히 방수량이 적으며 관련기준에서 요구하는 성능요건을 만족하는 미분무 노즐을 개발하고자 실물화재실험을 수행하였다. 본 설비의 화재시나리오는 크게 두 가지로 트럭화물화재와 승용차화재로 구분되며, 각각 고정 설치된 미분무 노즐과 화원과의 세 가지 위치에 대한 시나리오로 이루어져 있다. 모든 화재실험은 30분간 진행되었으며 천장부의 가스온도와 우드펠릿의 손상율, 타깃합판의 착화여부로 판단되었다. 본 논문은 두 가지 화재실험 중 조건이 더욱 까다로운 트럭화재용 미분무 노즐의 결과를 위주로 방수압력과 방수량, 미분무수의 유동특성에 따른 화재실험결과와 화재진압특성을 고찰하였으며, 수십 회의 반복실험 결과 분당 약 40 L의 유량을 가지는 저압 미분무 노즐로 Ro-Ro구역의 화재진압이 가능한 것으로 나타났다.

Improved Diagnostic Accuracy of Pancreatic Diseases with a Combination of Various Novel Serum Biomarkers - Case Control Study from Manipal Teaching Hospital, Pokhara, Nepal

  • Farooqui, Mohammad Shamim;Mittal, Ankush;Poudel, Bibek;Mall, Suhas Kumar;Sathian, Brijesh;Tarique, Mohammad;Farooqui, Mohammad Hibban
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권5호
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    • pp.2171-2174
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    • 2012
  • Background: Pancreatic cancer is a distressing disease with a miserable prospects and early recognition remains a challenge due to ubiquitous symptomatic presentation, deep anatomical location, and aggressive etiology. False positives and problems in distinguishing pancreatitis from adenocarcinoma limit the use of CA 19-9 as both disorders can present with similar symptoms and share radiographic physiognomies. This study aimed to assess the relative increase in accuracy of diagnosing the patients with chronic pancreatitis, benign neoplasm of pancreas and adenocarcinomas with CA 19-9, haptoglobin, and serum amyloid A in comparison to CA 19-9 alone. Materials and Methods: This hospital based case control study was carried out in the Departments of Medicine and Biochemistry of Manipal Teaching Hospital, Pokhara, Nepal, between $1^{st}$ January 2010 and $31^{st}$ December 2011. The variables assessed were age, gender, serum CA19-9, serum haptoglobulin, serum Amyloid A. The data were analyzed using Excel 2003, R 2.8.0 Statistical Package for the Social Sciences (SPSS) for Windows Version 16.0 (SPSS Inc; Chicago, IL, USA) and the EPI Info 3.5.1 Windows Version. Results: Out of 197 cases of pancreatic disease, maximum number of assumed cases were of adenocarcinoma of pancreas (95). Number of males (59) were more than females (36) in assumed cases of adenocarcinoma of pancreas. The mean values of CA19-9 raised considerably in cases of chronic pancreatitis, benign neoplasm and adenocarcinoma of pancreas when compared to controls. The highest augmention in CA19-9 values were in cases of adenocarcinoma of pancreas. The p-value indicates that in cases of chronic pancreatitis, there was not significant increase in precision of diagnosis. Conclusions: These statistics established that haptoglobin and SAA are useful in discriminating cancer from benign conditions as well as healthy controls.

Role of Hyperinsulinemia in Increased Risk of Prostate Cancer: A Case Control Study from Kathmandu Valley

  • Pandeya, Dipendra Raj;Mittal, Ankush;Sathian, Brijesh;Bhatta, Bibek
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권2호
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    • pp.1031-1033
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    • 2014
  • Aim: To investigate the effect of hyperglycemia and hyperinsulinemia on prostate cancer risk. Materials and Methods: This hospital based study was carried out using data retrieved from the register maintained in the Department of Biochemistry of a tertiary care hospital of Kathmandu, Nepal between $31^{st}$ December, 2011 and $31^{st}$ October, 2013. The variables collected were age, serum cholesterol, serum calcium, PSA, fasting blood glucose, serum insulin. Analysis was performed by descriptive statistics and testing of hypothesis using Excel 2003, R 2.8.0, Statistical Package for the Social Sciences (SPSS) for Windows Version 16.0 (SPSS Inc; Chicago, IL, USA) and the EPI Info 3.5.1 Windows Version. Results: Of the total 125 subjects enrolled in our present study, 25 cases were of PCa and 100 were healthy controls. The mean value of fasting plasma glucose was 95.5 mg/dl in cases of prostatic carcinoma and the mean value of fasting plasma insulin was $5.78{\mu}U/ml$ (p value: 0.0001*). The fasting insulin levels ${\mu}U/ml$ were categorized into the different ranges starting from ${\leq}2.75$, >2.75 to ${\leq}4.10$, >4.10 to ${\leq}6.10$, > $6.10{\mu}U/ml$. The maximum number of cases of prostatic carcinoma of fasting insulin levels falls in range of > $6.10{\mu}U/ml$. The highest insulin levels (> $6.10{\mu}U/ml$) were seen to be associated with an 2.55 fold risk of prostatic carcinoma when compared with fasting insulin levels of (< $2.75{\mu}U/ml$). Conclusions: Elevated fasting levels of serum insulin appear to be associated with a higher risk of prostate cancer.