• Title/Summary/Keyword: Retrospective Study

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Retrospective Exposure Assessment of Wafer Fabrication Workers in the Semiconductor Industry (반도체 웨이퍼 가공 공정 역학 조사에서 과거 노출 평가 방법 고찰)

  • Park, Dong-Uk
    • Journal of Environmental Health Sciences
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    • v.37 no.1
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    • pp.12-21
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    • 2011
  • The objective of this study is to review retrospective exposure assessment methods used in wafer fabrication operations to determine whether adverse health effects including mortality or cancer incidence are related to employment in particular work activities and to recommend an appropriate approach for retrospective exposure assessment methods for epidemiological study. The goal of retrospective exposure assessment for such studies is to assign each study subject to a workgroup in such a way that differences in exposure within the workgroups are minimized, as well as to maximize the contrasts in exposure between workgroups. To reduce the misclassification of exposure and to determine if adverse health effects including mortality or cancer incidence are related to particular work activities of wafer fabrication workers, a minimum requirement of work history information on the wafer manufacturing eras, job and department at which they were exposed should be assessed. Retrospective assessment of the task that semiconductor workers performed should be conducted to determine not only the effect of a particular job on the development of adverse health effects including mortality or cancer incidence, but also to adjust for the healthy worker effect. In order to identify specific hazardous agents that may cause adverse health effects, past exposure to a specific agent or agent matrices should also be assessed.

A study on retrospective structure in narrative comics -Focusing on webtoon - (서사만화에서의 회상구조 연구 -웹툰 <무빙>을 중심으로-)

  • Kim, Seong-jae;Lee, Hae-kwang
    • Cartoon and Animation Studies
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    • s.46
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    • pp.107-128
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    • 2017
  • Time is an indispensable element in creating a story. This makes comics artists use various time techniques such as prolepsis, summary, ellipsis and flashback to increase immersion in story when they create comics. This is intended to make a study on retrospective structure among various temporal structures. Retrospective structure means progress in different time sequence, and increases immersion by making readers become strained or relaxed. Besides, retrospective structure plays a role of increasing or decreasing the pace of story. The person who systematically put the retrospective structure into shape is $G\acute{e}rard$ Genette. He in his book "Narrative Discourse" classified retrospective structure into three types. These are made up of structure of analepse externes, analepse internes and analepse mixted. This makes a study on retrospective structure in narrative comics based on $G\acute{e}rard$ Genette's retrospective structure. To this end, Kang Full's webtoon was analyzed. The reason to analyze Kang Full's is that this work has storyline where things happening in parental generation is interwined with things in offspring generation, accordingly this is work suitable for studying the retrospective structure. This study is intended to examine whether three retrospective structures suggested by $G\acute{e}rard$ Genette are actually used through an analysis of , and as a result, it is intended to prove the fact that retrospective structure has an effect on immersion in work.

A Validation Study of Retrospective Pre-post Testin the Affective Domain in Science Learning:for Scientifically Gifted Elementary Students (과학학습의 정의적 영역에서 사전-사후 통합 검사 설계의 타당화 연구: 과학영재를 대상으로)

  • Lim, Chae-Seong;Park, Hyoung-Min
    • Journal of Korean Elementary Science Education
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    • v.36 no.3
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    • pp.219-226
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    • 2017
  • In this study, the reliability and validity of the retrospective pre-post test were analyzed in order to solve the problem of traditional pre-post test including response shift bias. Samples of the study were 162 elementary school students who are studying at the S university gifted education center in Seoul. Before completion of the field trip, we conducted pre test of science-related attitudes. After completion of the field trip, respondents were asked to compare their responses of pre and post science-related attitudes to quantitatively analyze the commonalities and differences of the two tests. To find out more characteristics, qualitative data such as daily records and interview were also gathered and analyzed. The major results of the study are as follows. First, for the paired t-test, there was no statistically significant difference between separate pre-test scores and retrospective pre-test. There was a very high correlation between the separate pre-test scores and the retrospective pre-test. Second, there were significant differences in all seven sub-factors of science-related attitudes between the retrospective pre-test and the post-test. Third, the separate pre-test scores showed a slightly higher tendency than the retrospective pre-test scores. This suggests that the response shift bias appears when it is performed the separate pre-test in affective domain. As a result of the interview, it was found that the evaluation standards of separate pre-test did not match with those of post-test. Forth, internal consistency reliability of the retrospective pre-test was higher than that of the separate pre-test. However, there were significant differences in six factors of science-related attitudes excluding the 'social implications of science' between the separate pre-test and the post-test. Based on these results, the retrospective pre-post test design provides simplicity and convenience to both respondents and investigators, as it is done with one test. The retrospective pre-post test design can be regarded as a valid design for the self-report measurement of affective domain on a single experimental group.

Review of the Retrospective Drug Utilization Review Program from Foreign Countries' Experience (외국의 후향적 DUR 제도 현황과 정책적 함의)

  • Kim, Dong-Sook;Kim, Su-Kyeong;Jang, Sun-Mee
    • YAKHAK HOEJI
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    • v.55 no.3
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    • pp.173-184
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    • 2011
  • The purpose of this study was to review foreign retrospective Drug Utilization Review(DUR), and so to suggest a development plan suitable for use with domestic situation. Literature review of foreign retrospective DUR program and domestic project such as DUR and prescribing analysis project were reviewed. To improve prescribing quality, developed countries such as US, Canada, UK, France, and Australia have implemented various forms of policy. Based on the review of foreign retrospective DUR program, we suggested to apply practical implementation of retrospective DUR program.

Canine Demodicosis - A Ten-year Retrospective Study (개의 모낭충증-최근 10년간의 발생동향)

  • 김상기
    • Journal of Veterinary Clinics
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    • v.14 no.1
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    • pp.136-139
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    • 1997
  • A retrospective study on 72 dogs with demodicosis, presented to Veterinary Teaching Hospital of Chonnam National University between 1987 and 1996, is reported. About 18% of the dogs with skin disease had demodicosis. About 75% of the patients with demodicosis were purebred dogs, and the short-haired breeds had a much higher incidence than do long-haired breeds. The age of the patient ranged from 1 month to 3 years, and about 63% of the patients were less than a year of age. Sex and seasons have been shown to have no effect on the development of demodicosis. A hereditary predisposition of generalized demodicosis has been observed from an affected litter.

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RETROSPECTIVE MULTICENTER STUDY OF CSM ENDOSSEOUS DENTAL IMPLANT

  • Park, Eun-Young
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.3
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    • pp.321-328
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    • 2007
  • Statement of problem. To work the economic limitation of dental implant usage, some types of domestic implant have been developing. But, there have been seldom reported about the clinical success rate of them as yet. Purpose. The aim of this retrospective multicenter study was to evaluate the performance of CSM implants(CSM company, Daegu, Korea). Material and methods. Thirty-five patients were rehabilitated with 150 CSM implants in this multicenter study. Results. The success rate was 96.2%. CSM Titanium fixtures can obtain slightly higher success rate when a cover screw was not used for implant installation than when used. However it doesn't show significant difference(p=.7615, Fisher's Exact test). Conclusion. This multicenter retrospective study demonstrated the efficacy of the CSM implant in the treatment of variety of clinical manifestation of tooth loss. And it can be assumed that whether a cover screw is used or not should no influence on the osseointegration.

Menstrual Cycle Characteristics and Premenstrual Syndrome Prevalence Based on the Daily Record of Severity of Problems in Korean Young Adult Women

  • Kim, Yae-Ji;Park, Young-Joo
    • Journal of Korean Academy of Nursing
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    • v.50 no.1
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    • pp.147-157
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    • 2020
  • Purpose: This descriptive study aimed to identify the menstrual cycle characteristics and premenstrual syndrome (PMS) prevalence in Korean young adult women using the retrospective and prospective Daily Record of Severity of Problems (DRSP). Methods: In the first stage, participants included 151 nursing students studying in a university located in Seoul. Data were collected from April 20 to June 2, 2017, using the questionnaire on menstrual characteristics, pictorial blood assessment chart, and retrospective DRSP. In the second stage, participants included 17 students with PMS, based on the screening conducted in the first stage. Data were collected using the prospective DRSP from May 29 to 2 September 2, 2017. Results: Of the study sample, 104 participants (68.9%) had regular periods. Those with regular periods had 11.97 periods annually with a menstrual cycle of 29.38 days and a period duration of 5.72 days. Fifty-five participants (37.4%) showed menorrhagia. Sixty-four participants (42.4%) were found to have PMS based on their retrospective DRSP. When the ratio of women (52.9%) with PMS shown in the prospective DRSP was used as a positive predictive value, the estimated PMS prevalence was 22.4%. Conclusion: This study provides clinically significant PMS prevalence among Korean young adult women, positive predictive value of the retrospective DRSP, and valid data to basically understand the menstrual cycle characteristics experienced by these women.

Retrospective Study of Crystalluria and Urinary Tract Symptoms in Dogs (개에서 발생한 결정뇨와 요로증후군에 대한 후향적 연구)

  • Oh, Won-Seok;Oh, Tae-Ho
    • Journal of Veterinary Clinics
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    • v.27 no.4
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    • pp.386-391
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    • 2010
  • This retrospective study was performed in 40 cases of canine crystalluria and urinary tract symptoms. Breed, age, sex, diet history and common clinical signs were investigated for patient information. CBC, serum chemistry, urinalysis, urine culture, urine sediment and urinary stone analysis were undertaken for clinicopathological diagnosis. Crystalluria and urinary tract symptoms occurred from 6 months till 14 years in this clinical investigation and the average age was 4.68 years. It had taken an average 7.4 weeks to correct crystalluria and urinary tract symptoms treated by supportive therapy and dietary management. In conclusion, regular clinical pathologic examination, treatment and diet management should be needed to prevent the formation of urolithiasis and urinary tract diseases in dogs with crystalluria and urinary tract symptoms.

Logistic Regression for Retrospective Studies

  • Shin, Mi-Young
    • Journal of Korean Society for Quality Management
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    • v.22 no.4
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    • pp.111-119
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    • 1994
  • We consider logistic models based on retrospective, case-control data with stratified samples and study the Weighted Exogeneous Sampling Maximum Likelihood (WESMU) We develop a consistent estimator of the asymptotic covariance matrix of the WESML estimator.

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The Assessment of the Breath Hold and the Free Breath Methods about the Blood Flow Evaluation by Using Phase Contrast MRI (위상대조도 자기공명영상을 이용한 심장 혈류평가에 있어서 호흡정지 기법과 비 호흡정지 기법의 비교평가)

  • Kim, Seong-Ho
    • Journal of radiological science and technology
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    • v.39 no.2
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    • pp.149-156
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    • 2016
  • Measurement of cardiac blood flow using the magnetic resonance imaging has been limited due to breathing and involuntary movements of the heart. The present study attempted to improve the accuracy of cardiac blood flow testing through phase contrast magnetic resonance imaging by presenting the adequate breathing method and imaging variables by comparing the measurement values of cardiac blood flow. Each was evaluated by comparing the breath hold retrospective 1NEX and non breath hold retrospective 1-3NEX in the ascending aorta and descending aorta. As a result, the average blood flow amount/velocity of the breath hold retrosepctive 1NEX method in the ascending aorta were $96.17{\pm}19.12ml/sec$, $17.04{\pm}4.12cm/sec$ respectively, which demonstrates a statistically significant difference(p<0.05) with the non-breath hold retrospective method 1NEX of $72.31{\pm}13.27ml$ and $12.32{\pm}3.85$. On the other hand, the average 2NEX blood flow and mean flow velocity is $101.90{\pm}24.09$, $16.84{\pm}4.32$, 3NEX $103.06{\pm}25.49$, $16.88{\pm}4.19$ did not show statistically significant differences(p>0.05).The average blood flow amount/ velocity of the breath hold retrospective 1NEX method in the descending aorta were $76.68{\pm}19.72ml/s$, and $22.23{\pm}4.8$, which did not demonstrate a significant difference in comparison to non-breath hold retrospective method 1-3 NEX. Therefore, the non breath hold retrospective method does not significantly differ in terms of cardiac blood flow in comparison with the breath hold retrospective method in accordance with the increase of NEX, so pediatric patients or patients who are not able to breathe well must have the diagnostic value of their cardiac blood flow tests improved.