• International Journal of Precision Engineering and Manufacturing
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• 제2권2호
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• pp.65-72
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• 2001

The design of multi-stage gear drives is a time-consuming process, since on includes more complicated problems, which are not considered in the design of single-stage gear drives. The designer has th determine the number of reduction stages and the gear ratios of each reduction state. In addition, the design problems include not only the dimensional design but also the configuration design of gear drive elements. There is no definite rule and principle for these types of design problems. Thus the design practices largely depend on the sense and the experiences of the designer , and consequently result in undesirable design solution. We propose a new generalized design algorithm to support the designer at the preliminary design phase of multi-stage gear drives. The proposed design algorithm automates the design process by integrating the dimensional design and the configuration design process. The algorithm consists of four steps. In the first step, a designer determines the number of reduction stage. In the second step. gear ratios se chosen by using the random search method. In the third step, the values of basic design parameter are chosen by using the generate and test method. Then, the values of other dimension, such ad pitch diameter, outer diameter, and face width, are calculated for the configuration design in the final step. The strength and durability of a gear is guaranteed by the bending strength and the pitting resistance rating practices by using the AGMA rating formulas. In the final step, the configuration design is carried out b using the simulated annealing algorithm. The positions of gears and shafts are determined to minimize the geometrical volume(size) of a gearbox, while satisfying spatial constraints between them. These steps are carried out iteratively until a desirable solution is acquired. The propose design algorithm has been applied to the preliminary design of four-stage gear drives in order to validate the availability. The design solution have shown considerably good results in both aspects of the dimensional and the configuration design.

• Journal of Preventive Medicine and Public Health
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• 제32권4호
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• pp.491-498
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• 1999

Objectives : To determine the relations between seven blood lipids such as total cholesterol(TC), triglyceride(TG), HDL-cholesterol(HDL), LDL-cholesterol(LDL), apolipoprotein A-1(Apo A1), apolipoprotein B(Apo B) and lipoprotein(a)(Lp(A)) and the coronary heart diseases(CHD), the quantitative techniques of meta-analysis were applied to studios of blood lipids and CHD in Koreans. Methods : We searched the Korean and the English literature published from 1980 to August, 1997 by manual search and bibliography review. Information on sample size, study design, participant characteristics(gender, age) and blood lipid levels were abstracted by reviewers using inclusion criteria. Estimates of the effect sizes of blood lipid levels on CHD in Koreans and corresponding 95% confidence intervals were calculated using random-effect models. Results : We identified 16 case-control studies to apply meta-analysis. The overall effect sizes for CHD were 20.3(95% CI: 14.23-20.22) in TC, 24.8(95% CI: 12.6-36.86) in TG, 15.16(95% CI: 3.99-26.33) in LDL, -3.48(95% CI: -5.79 - -1.17) in HDL, -9.78(95% CI: -16.98 - -2.58) in Apo-a1, 17.88(95% CI: 9.72-26.05) in Apo B and 18.95(95% CI: 17.88-20.02) in Lp(a). Conclusions : Our results suggested that seven blood lipids were significantly associated with CHD in Koreans. Well-designed and prospective studies between blood lipids and CMD in Koreans should be peformed.

• 대한한의학원전학회지
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• 제21권3호
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• pp.297-306
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• 2008

Background : Gigong(氣功, Qigong) is one energy-healing intervention used to prevent and cure ailments and to improve health through regular practice. Although Gigong(氣功, Qigong) - neither itself nor its postulated mechanism of action - are within the paradigm of modern Western medical science, effects on the human body could be possible. Objectives : This study aims to review the bibliography, biological responses and therapeutic effects of Gigong. In the process, this review will grasp trends in this field of studies and will direct further researches into the right direction. Method : The computerized Korean databases were searched from their respective inceptions up to January 2008. The search terms used were 'Gi(氣, Qi)', 'Gigong(氣功, Qigong)', 'Doin(導引)', 'Training', 'Bioenergy', 'life nurturing' and random or Korean language terms related to Gigong. Several specialized journals were also manually searched for relevant articles. Result : Since the 1990's, Gigong papers in the Korean Literature is increased. Clinical research studies are among the most control design study. Research subjects are less patient than the general public. The most common treatment disease was Musculo-skeletal disorder Conclusions : The depth study for the each Gigong(氣功, Qigong) is needed. Specifically, I think it should be a clinical studies and qualitative research methods for evaluation are needed.

• 대한한방내과학회지
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• 제39권3호
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• pp.426-442
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• 2018

Objective: This study aimed to compare the effects of Zusanli and nonacupoint electroacupuncture stimulation on ultrasonographic gastric emptying and vital signs in eight healthy participants. Gastric emptying and its rate of change were analyzed to search for correlation with physical characteristics such as body mass index (BMI), sternocostal angle, and abdominal wall thickness. Methods: Eight healthy participants with no gastrointestinal disorders were enrolled in this study. Each participant went through three abdominal sonographies for gastric emptying assessment. At the second and third visits, participants received Zusanli and nonacupoint electroacupuncture stimulation in a random order. During the study period, we examined the BMI, sternocostal angle, and abdominal wall thickness of all participants. Vital signs (blood pressure, heart rate, and temperature) were also examined before and after the electroacupuncture stimulation. Results: Electroacupuncture stimulation at Zusanli significantly improved gastric emptying when compared to nonacupoint stimulation. Gastric emptying showed a positive correlation with BMI, sternocostal angle, and abdominal wall thickness, but this correlation was statistically insignificant. The improvement rate of gastric emptying by Zusanli electroacupuncture stimulation showed a positive correlation with BMI and sternocostal angle and a negative correlation with abdominal wall thickness. However, such results were also statistically insignificant. Among vital signs, only heart rate showed a significant decrease according to Zusanli electroacupuncture stimulation. Conclusions: A significant effect of Zusanli electroacupuncture was confirmed through ultrasonographic gastric emptying in healthy participants.

• 정보관리학회지
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• 제33권3호
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• pp.321-343
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• 2016

본 연구의 목적은 1) 소설 속 지명 데이터베이스(DB)를 구축하고, 2) 확장 가능한 지명 DB를 위해 자동으로 지명을 추출하여 데이터베이스를 갱신하며, 3) 데이터베이스 내의 소설지명과 용례를 검색하고 시각화하는 파일럿시스템을 구현하는 데 있다. 특히, 학습자료(training)에 해당하는 말뭉치(corpus)를 확보하기 어려운, 소설지명과 같이 현재 잘 쓰이지 않는 개체명을 자동으로 추출하는 것은 매우 어려운 문제이다. 효과적인 지명 정보 추출용 학습자료 말뭉치 확보 문제를 해결하기 위해 본 논문에서는 이미 수작업으로 구축된 웹 지식(어휘사전)을 활용하여 학습에 필요한 충분한 양의 학습말뭉치를 확보하는 방안을 적용하였다. 이렇게 확보된 학습용 코퍼스와 학습된 자동추출 모듈을 가지고, 새로운 지명 용례를 찾아 추가하는 지명 데이터베이스 확장 도구를 만들었으며, 소설지명을 지도 위에 시각화하는 시스템을 설계하였다. 또한, 시범시스템을 구현함으로써 실험적으로 그 타당성을 입증하였다. 끝으로, 현재 시스템의 보완점을 제시하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10421-10425
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• 2015

Background: While the incidence of non-Hodgkins lymphoma (NHL) has been rising worldwide, the reasons remain undefined. Recent research has focused on effect of red andf processed meat intake as a risk factor, but with inconclusive results. We therefore conducted a meta-analysis of data published to date, to ascertain the overall association between intake and NHL. Materials and Methods: A published literature search was performed through Pubmed, Cochrane Library, Medline, and Science Citation Index Expanded databases for articles published in English. Pooled odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated using random or fixed effects models. Heterogeneity was assessed using Chi-square and I2 statistics. Dissemination bias was evaluated by funnel plot analysis.We performed a formal meta-analysis using summary measures from these studies. Results: In total, 11 published studies were included in the final analysis. The combined analysis revealed that there was significant association between the red meat and NHL risk (OR=1.10, 95%CI: 1.02 to 1.19, p=0.01). Additionally, there was showed significance association between processed red meat and NHL risk (OR=1.17, 95%CI: 1.06 to 1.29, p=0.001). In subgroup analysis, a statistical significant association was noted between diffuse large B-cell lymphoma (DLBCL) (OR=1.20, 95%CI: 1.04 to 2.37, P=0.01) and red meat intake. Conclusions: In this meta-Analysis, there was evidence for association between consumption of red meat, or processed meat and risk of NHL, particularly with the DLBCL subtype in the red meat case.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6863-6869
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• 2014

Objectives: Several preclinical and observational studies have shown that anti-diabetic medications (ADMs) may modify the risk of lung cancer. We performed a systematic review and meta-analysis evaluating the effect of metformin, sulfonylureas (SUs), thiazolidinediones (TZDs), and insulin on the risk of lung cancer in patients with diabetes mellitus (DM). Materials and Methods: We conducted a systematic search of Pubmed and Web of Science, up to August 20, 2013. We also searched the Conference Proceedings Citation Index (CPCI) and China National Knowledge Infrastructure (CNKI) for abstracts from major meetings. Fixed or random effect pooled measures were selected based on heterogeneity among studies, which was evaluated using Q test and the I2 of Higgins and Thompson. Meta-regression was used to explore the sources of between-study heterogeneity. Publication bias was analyzed by Begg's funnel plot and Egger's regression test. Associations were assessed by odds ratios (ORs) with 95% confidence intervals (CIs). Results: A total of 15 studies (11 cohort, 4 case-control) were included in this meta-analysis. In observational studies no significant association between metformin (n=11 studies; adjusted OR=0.99, 95%CI: 0.87-1.12), SUs (n=5 studies; adjusted OR=0.98, 95%CI: 0.79-1.22), or TZDs (n=7 studies; adjusted OR=0.92, 95%CI: 0.75-1.13), insulin (n=6 studies; adjusted OR=1.13, 95%CI: 0.79-1.62) use and risk of developing lung cancer was noted. There was considerable inherent heterogeneity between studies not explained by study design, setting, or location. Conclusions: Meta-analysis of existing studies does not support a protective or harmful association between ADMs use and risk of lung cancer in patients with DM. There was considerable heterogeneity across studies, and future, well-designed, prospective studies would be required for better understanding of any association.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2571-2576
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• 2014

Background: Published studies on the association between the exonuclease 1 (EXO1) Glu589Lys polymorphism and cancer susceptibility have yielded conflicting results. Thus, a meta-analysis of published studies was performed to assess the possible association. Materials and Methods: All eligible case-control studies published up to January 2013 on the association between the EXO1 Glu589Lys polymorphism and cancer susceptibility were identified by searching PubMed, Web of Science, Science Direct and hand search. Either fixed-effect or random-effect models were used to calculate pooled odds ratios (ORs) with 95% confidence intervals (CIs) using the Comprehensive Meta-Analysis software version 2.2. Results: A total of 4,391 cancer cases and 4,339 controls from 10 studies were included. Overall, no significant association between the EXO1 Glu589Lys polymorphism and cancer susceptibility was observed in either genetic model. However; in subgroup analyses by cancer type, a significant association between EXO1 Glu589Lys and lung cancer risk was found (Lys vs Glu: OR=1.23, 95%CI=1.07-1.41, $p_{heterogeneity}$=0.05). Further, subgroup analysis by ethnicity indicated that there was a statistically increased cancer risk in Asians (Lys vs Glu: OR=1.42, 95%CI=1.30-1.55, $p_{heterogeneity}$=0.07; Lys/Lys vs Glu/Glu: OR=1.93, 95%CI=1.20-3.12, $p_{heterogeneity}$=0.01; Lys/Lys+Glu/Lys vs Glu/Glu: OR=1.52, 95%CI=1.37-1.68, $p_{heterogeneity}$=0.42; Lys/Lys vs Glu/Lys+Glu/Glu: OR=1.68, 95%CI=1.07-2.65, $p_{heterogeneity}$=0.02). However, significant association was absent in Caucasians. Conclusions: This meta-analysis suggests, for the first time, that the EXO1 Glu589Lys polymorphism is not associated with overall cancer susceptibility, although marginal associations were found for lung cancer and Asian subgroups. Additional well-designed studies with larger sample size focusing on different ethnicities and cancer types are needed to confirm these findings.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2857-2861
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• 2014

More and more evidence indicates that the G801A polymorphism in the CXCL12 gene might be associated with susceptibility to breast carcinoma in humans being. However, individually published results have been inconsistent. The purpose of this meta-analysis was to investigate the association between the G801A polymorphism in the CXCL12 gene and breast carcinoma risk. A complete search strategy was done by the electronic databases including PubMed and Chinese Biomedical Literature Database. A meta-analysis including seven individual studies was carried out in order to explore the association between the G801A polymorphism in the CXCL12 gene polymorphisms and breast carcinoma. The pooled odds ratios (ORs) and their corresponding 95% confidence intervals (95%CIs) between the G801A polymorphism in the CXCL12 gene and breast carcinoma risk were assessed by the random-effects model. A significant relationship between the G801A polymorphism in the CXCL12 gene and breast carcinoma was discovered in an allelic genetic model (OR: 1.214, 95%CI: 1.085-1.358, p=0.001), a homozygote model (OR: 1.663, 95%CI: 1.240-2.232, p=0.001), a heterozygote model (OR: 1.392, 95%CI: 1.190-1.629, p=0.000), a recessive genetic model (OR: 1.407, 95%CI: 1.060-1.868, p=0.018) and a dominant genetic model (OR: 1.427, 95%CI: 1.228-1.659, p=0.000). On sub-group analysis based on ethnicity, significance was observed between the European group and the mixed group. A significant relationship was found between the G801A polymorphism in the CXCL12 gene and breast carcinoma risk. Individuals with the A allele of the G801A polymorphism in the CXCL12 gene are under a higher risk for breast carcinoma.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9085-9091
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• 2014

Background: Epidemiology studies have shown an inconclusive relationship between phytoestrogen intake and ovarian cancer risk and there have been no relevant meta-analyses directly regarding this topic. The purpose of the present meta-analysis was therefore to investigate any association between phytoestrogen intake and ovarian cancer in detail. Materials and Methods: We conducted a search of PubMed, EMBASE, EBSCO, the Cochrane Library, CNKI and Chinese Biomedical Database (up to April 2014) using common keywords for studies that focused on phytoestrogen and ovarian cancer risk. Study-specific risk estimates (RRs) were pooled using fixed effect or random-effect models. Results: Ten epidemiologic studies were finally included in the meta-analysis. The total results indicated higher phytoestrogen intake was associated with a reduced ovarian cancer risk (RR, 0.70; 95%CI: 0.56-0.87). The association was similar in sensitivity analysis. Meta regression analysis demonstrated sources and possibly types and regions as heterogeneous factors. Subgroup analysis of types, sources and regions showed that isoflavones (RR: 0.63; 95%CI: 0.46, 0.86), soy foods (RR: 0.51; 95%CI: 0.39, 0.68) and an Asian diet (RR: 0.48; 95%CI: 0.37, 0.63) intake could reduce the incidence of ovarian cancer. Conclusions: Our findings show possible protection by phytoestrogens against ovarian cancer. We emphasize specific phytoestrogens from soy foods, but not all could reduce the risk. The habit of plentiful phytoestrogen intake by Asians is worthy to recommendation. However, we still need additional larger well designed observational studies to fully characterize underlying associations.