• Genomics & Informatics
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• 제5권3호
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• pp.113-117
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• 2007

The development of microarray technology has facilitated the understanding of gene expression profiles. Despite its convenience, the cause of dye-bias that confounds data interpretation in dual-color DNA microarray experiments is not well known. In order to economize time and money, it is necessary to identify the cause of dye bias, since designing dye-swaps to reduce the dye-specific bias tends to be very expensive. Hence, we sought to determine the reliable cause of systematic dye bias after treating murine macrophage RAW 264.7 cells with 2-keto-3-deoxyoctonate (KDO), interferon-beta $(IFN-{\beta})$, and 8-bromoadenosine (8-BR). To find the cause of systematic dye bias from the point of view of fluorescence quenching, we examined the correlation between systematic dye bias and the proportion of each nucleotide in mRNA and oligonucleotide probe sequence. Cy3-dye bias was highly correlated with the proportion of adenines. Our results support the fact that systematic dye bias is affected by fluorescence quenching of each feature. In addition, we also found that the strength of fluorescence quenching is based on not only dye-dye interactions but also dye-nucleotide interactions as well.

• PNF and Movement
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• 제20권2호
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• pp.147-156
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• 2022

Objective: Electrical stimulation is an assistive technology used to aid the recovery of upper limb use after stroke. The purpose of this systematic review was to determine the effects of electrical stimulation on upper extremity function in individuals with hemiparetic stroke and to develop an evidence base that supports the use of electrical stimulation for upper limb recovery after stroke. Design: A systematic review based on randomized controlled trials (RCTs). Methods: Studies published before April 20 2021 were collected for this review by searching PubMed, four other databases, and RCTs that reported the effects of electrical stimulation on upper extremity function in individuals with the characteristic stroke type. Information on the following parameters was extracted from each study: surname of first author, published year, country, participants, intervention, intervention's intensity, comparison, outcomes, additional therapy, and summary of results. This review also evaluated the bias within each study, including any selection bias, performance bias, detection bias, attrition bias, and reporting bias. Results: This review included five RCTs, and 208 stroke patients were included in the analysis. Stroke patients who underwent electrical stimulation showed significantly improved grip and pinch strengths, wrist range of motion, and basic daily living compared to those in the control group; however, there was no improvement in upper extremity function. Of the selected papers, 60% showed a "high risk" of performance bias, and 20% showed a "high risk" of detection bias. Conclusions: The results of this systematic review suggest that electrical stimulation provides some benefits to stroke patients, such as improved hand strength and range of motion. However, future studies are needed to provide clinical evidence of the effects of electrical stimulation on upper extremity function in stroke patients.

• Journal of Positioning, Navigation, and Timing
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• 제13권2호
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• pp.179-187
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• 2024

The performance of a Strapdown Inertial Navigation System (SDINS) relies heavily on the accuracy of sensor error calibration. Systematic calibration is usually employed when only a 2-axis turntable is available. For systematic calibration, the body frame is commonly defined with respect to sensor axes for ease of computation. The drawback of this approach is that sensor axes may undergo time-varying deflection under temperature change, causing pseudo gyro bias. The effect of pseudo gyro bias on navigation performance is negligible for low grade navigation systems. However, for higher grade systems undergoing rapid temperature change, the error is no longer negligible. This paper describes in detail conditions leading to the presence of pseudo gyro bias, and proposes two techniques for mitigating the error. Experimental results show that applying these techniques improves navigation performance for precision SDINS, especially under rapid temperature change.

• 한국조사연구학회지:조사연구
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• 제12권3호
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• pp.25-48
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• 2011

본 연구에서는 선거 출구조사에서 발생하는 편향을 분석하기 위해, 먼저 2010년 전국동시지방선거 출구조사의 표본설계와 표본추출오차, 그리고 무응답 현황 및 예측오차 등을 살펴보고, 이를 토대로 출구조사에서 체계적으로 발생하는 지역별 편향 문제를 다루었다. 출구조사에서 발생하는 편향을 통계적으로 검증하기 위해 Martin et al.(2005)이 제안한 예측 정확성 척도인 통계량 A를 사용하였다. 2010년 지방선거를 포함해 2006년 지방선거와 2007년 대통령 선거 방송사 출구조사 자료를 토대로 시 도 단위에서 지역별 편향을 분석해 본 결과, 여당 성향이 강한 지역에서는 여당 후보를 과대 추정하는 편향이 체계적으로 발생하고 있으며, 여당 성향이 강해질수록 이런 편향이 더 강해진다는 것을 확인할 수 있었다. 이런 연구결과는 향후 출구조사의 정확성 제고를 위한 방안을 모색하는 데 크게 기여할 수 있을 것으로 기대된다.

• 한국항해항만학회지
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• 제37권5호
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• pp.447-452
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• 2013

해상교통관제시스템(VTS)은 선박의 위치, 속도, 침로 등 해상 교통 정보를 획득하기 위하여 다수의 해상감시레이더를 주요 센서로 이용하고 있으며, 거리 및 방위각 바이어스와 같은 2차원 해상감시레이더의 시스템 오차는 레이더 영상 및 표적 추적정보의 정확도를 크게 저하시킬 수 있다. 따라서 해상교통관제시스템에서 정확한 표적정보를 제공하기 위하여 레이더의 시스템 오차는 정밀하게 보정되어야 한다. 본 논문에서는 VTS 관제영역에 설치된 항로표지의 위치정보를 이용하여 2차원 해상감시레이더의 거리 및 방위각 오차를 보정하기 위한 방법을 제안한다. 2차원 레이더 측정값의 표준오차 모델과 항로표지 위치정보로부터 측정 잔차 모델을 유도하고, 레이더 시스템 오차를 추정하기 위한 선형 칼만필터를 설계한다. Monte-Carlo 모의실험을 통하여 제안한 방법을 검증하고, 항로표지 정보의 개수에 따른 레이더 시스템 오차 추정의 수렴 특성 및 정확도를 분석한다.

• Journal of Acupuncture Research
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• 제32권3호
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• pp.135-146
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• 2015

Objectives : This study was designed to evaluate clinical evidence of moxibustion treatment for knee pain. Methods : All processes were independently carried out by three investigators. A literature search was performed in 3 databases from their inception to May 2015. Ten reports were found based on their title, abstract and text. Following this, data extraction and analysis were done using a risk of bias(ROB) and through an assessment of multiple systematic reviews(AMSTAR). Results : 10 studies(6RCT, 2SR, 2CR) were included. Generally, indirect moxibustion was used for knee pain, but only one study indicated the use of direct moxibustion. Moxibustion was shown to be effective in treating knee pain, and the number of required treatments was fourteen on average. In assessing risk of bias, indefinite and uncertain information made all included trials subject to a high risk of bias. On the other hand, SR showed all evaluation items in the assessment of multiple systematic reviews, with the exception of an included or excluded studies list. Conclusions : Because of deficient study design or limited research planning, there is not sufficient evidence to allow for any conclusion about the efficacy of moxibustion for knee pain. Therefore, well-designed high quality trials are needed from now on.

• 응용통계연구
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• 제22권2호
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• pp.375-385
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• 2009

2007년 12월의 대통령선거 과정에서 행해진 수많은 전화 여론조사에서 이명박 후보가 일관되게 앞자리를 지켰다. 많은 수의 여론조사가 시행되는 경우 개별 여론조사의 표본추출오차는 상쇄되어 소멸한다. 그러나 일정한 편향은 많은 수의 조사가 실행된다 하더라도 잔존하므로 중요한 문제가 아닐 수 없다. 우리나라의 전화조사는 지역, 성과 연령대를 고려한 할당추출(quota sampling)을 사용하며 대부분 전화번호부를 표집 틀로 한다. 조사 거절률도 높은 편이다. 이에 따라 조사표본들이 할당변인 외의 인구사회적 속성에서 모집단을 잘 대표하지 못할 수 있다. 이 연구의 목적은 허명회 등 (2004)의 연구 방법른을 2007년에 수행된 대통령선거 여론조사 L8개 사례에 적용하여 다음 물음에 답하는 데 목적이 있다. - 물음 1. 각후보에 대한 선호도 또는 지지율에 체계적 편향이 있지 않았는가? - 물음 2. 편향이 있었다면, 그 원인이 어디에 있는가? 첫째 물음에 답하기 위하여 2007년 11월 이후 시행된 11개 사례 자료에 지역, 성과 연령대 외에 직업과 학력까지 고려한 반복비례가중법(rim weighting)을 적용해보았다. 그 결과, 이명박 후보의 지지율이 평균 1.4%P 과다 추정되었던 것으로 나타났다. 반면, 정동영 후보의 지지율은 평균 0.6%P 과소 추정되었고 이에 따라 두 후보간 지지율 차이가 2.0%P (= 1.4+0.6) 과다하게 추정되었던 것으로 보여진다. 둘째 물음에 답하기 위하여 위의 11개 사례 자료에서 이명박 후보 지지를 종속변수로 하는 로지스틱 회귀 분석을 하였다. 그 결과, 전화조사 표본에서의 저학력자 과소 및 가정주부의 과다가 이명박 편향의 원인이 되는 것으로 밝혀졌다.

• 한방안이비인후피부과학회지
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• 제30권3호
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• pp.166-181
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• 2017

Objectives : The study was done to verify the relation between early-onset androgenetic alopecia(AGA) and metabolic syndrome(MetS). Methods : Data were collected through electronic database including KoreaMed, National Assembly Library, KMBASE, NDSL, KCI, KERIS, Google Scholar, Pubmed, Cochrane CENTRAL and EBSCO MEDLINE. A total of 13 case-control studies related to the MetS of early-onset alopecia patients were used for the systematic review and meta-analysis. Risk of bias of included studies were assessed by RoBANS tool. RevMan5.3, CMA3 were used for the meta-analysis. Results : In 13 evaluated articles, most frequent bias was the participant selection bias that was found in 10 articles. Significant association between early-onset AGA and MetS was found in 10(76.9%) out of 13 articles in the systematic review. In meta-analysis, early-onset male AGA was associated with increased risk of metabolic syndrome(OR: 3.73, 95% CI:2.49 -5.61). Conclusions : AGA, particularly early -onset male AGA, is significantly associated with MetS. Therefore all patients with early onset male AGA should be suggested to take preventive treatment to reduce the risk of MetS and various problems associated with it.

• 여성건강간호학회지
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• 제26권4호
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• pp.274-284
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• 2020

Purpose: The purpose of this study was to investigate the effects and characteristics of health care programs for pregnant women with gestational diabetes mellitus (GDM) in Korea. Methods: This study was conducted according to the Cochrane Collaboration's systematic literature review handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guideline. We searched eight international and domestic electronic databases for relevant studies. Two reviewers independently selected the studies and extracted data. For each study, information on the research method, participants, characteristics of the program, and results were extracted using a previously established coding table. The National Evidence-based Healthcare Collaborating Agency's risk of bias assessment tool for non-randomized studies was used to assess the risk of bias of the included articles. A qualitative review of the selected studies was performed because the interventions differed considerably and the measured outcomes varied. Results: Out of 128 initially identified papers, seven were included in the final analysis. The risk of bias was evaluated as generally low. Health care programs for pregnant women with GDM showed positive effects on blood glucose control. Anxiety and depression were reduced, and self-management and self-care behavior, self-efficacy, and maternal identity improved. Conclusion: Our study provides clinical evidence for the effectiveness of health care programs for pregnant women with GDM, and its results can be used to support the development of health care programs for GDM. More well-designed research is needed on GDM, especially studies that deal with emotional stress and apply a family-oriented approach.

• Physical Therapy Rehabilitation Science
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• 제10권2호
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• pp.185-196
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• 2021

Objective: Falling is one of main accident to facilitate the physical injuries in order adults. The purpose of the systematic review was to determine the effects of postural balance training whether the recovery of falls in elderly with normal physical function or not throughout summing the selected studies quantitatively. Design: A systematic review Methods: MEDLINE and other four databases were searched up to April 20, 2021 and randomized controlled trials (RCTs) evaluating postural balance approaches on fall risks in elderly. The researched studies excluded the double studies, titles and abstract, and finally full-reported study. The selected RCTs studies were extracted characteristics of the studies and summary of results based on PICOS-SD (population, intervention, comparison, outcomes, and setting- study design) model to synthesize the papers qualitatively. Results: The review involved 22 RCT reports with 4,847 community older adults aged 65 years or over. Nineteen of the selected RCT studies reported dual or multimodal exercises show the beneficial effect for older adults compared to one-type treatment or no intervention. All of selected showed low risk in the selection, attrition, and reporting bias. However, detection bias showed low risk at 75% records of the involved RCTs and performance bias was low risk at only three records. Conclusions: The results of the systematic review propose that a standardized therapeutic approach and the intensity are needed for improving risk of falls in older adults.