• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.719-720
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• 2008

This paper deals with analytical approach for rotor loss prediction of permanent magnet synchronous generator(PMSG). The rotor losses of synchronous generator are induced by the magnets. Since stator of our model is skewed, slotting effect can be negligible for our PM wind turbine generator. In order to calculate eddy current, this paper derives analytical solutions by the magnetic vector potential. Finally this paper compared analytical result with eddy current density obtained from finite element(FE) calculations using phase current harmonics analysis.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.97-102
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• 2005

This paper presents feed rate optimizaton of a PMLSM driven feed-slide for mininum vibrations by smoothing velocity curve with finite jerk. First of all, the PMLSM was designed and made to reduce detent force. Next, a PMLSM driven feed-slide system was mathematically modeled as a 4-degree-of-freedom lumped parameter model. The key idea of our vibration minimization method is to find out the most appropriate smooth velocity curve with finite jerk. The validity of our proposed method has been verified by comparing computer simulation results of the feed-slide model with experimental ones.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.8
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• pp.351-357
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• 2005

This paper presents vibration minimization of a PMLSM driven feed-slide by using optimized smooth velocity curve with finite jerk. First of all, the PMLSM was designed and made to reduce detent force. Next, a PMLSM driven feed-slide system was mathematically modeled as a 4-degree-of-freedom lumped parameter model. The key idea of our vibration minimization method is to find out the most appropriate smooth velocity(feedrate) curve with finite jerk. The validity of our proposed method has been verified by comparing computer simulation results of the feed-slide model with experimental ones.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.7
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• pp.75-80
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• 2014

The small wind turbines has the merits of setting up with low costs by individuals, and get the energy saving effects that, it has the secured, separate markets from the big range systems, and the developing of it is continuously proceeding. The objective of this paper is to provide the design characteristics analysis of a permanent magnet synchronous generator(PMSG) skewed for magnet of rotor, the main advantage to be explored with the use of a split core design is the reduction in manufacturing costs and its simplicity in manufacture, compared to the manufacturing costs of a core skew PM machine. This thesis is aiming mainly analyzing the characteristics of the prototype to verify through Finite Element Method(FEM) and tests.

• ALGAE
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• v.27 no.1
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• pp.33-42
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• 2012

Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and frond sizes between epilithic and epiphytic populations. Harvest shores were gently sloping boulder fields with boulders typically about 0.5-1.0 m with dense cover of P. palmata on many of the rocks. Non-harvest shores (with or without P. palmata) consisted of boulders that were smaller or larger than harvest shores, or bedrock; when P. palmata was present on nonharvest sites it was typically epiphytic on other algae (e.g., Fucus spp., Mastocarpus stellatus, Devaleraea ramentacea). Harvestable epiphytic populations occurred only in high current areas. While there was little difference in average cover of P. palmata harvest and non-harvest shores ($31.2{\pm}13.7%$ vs. $19.4{\pm}7.3%$, mean ${\pm}$ standard deviation [SD]), the cover of P. palmata on harvest shores was highly skewed such that individual boulders often had >90% cover while adjacent rocks had little. Frond length of large fronds was greater on harvested shores, and mean frond density ($g\;m^{-2}$) was three times higher than the mean density on the non-harvested shores. Frond lengths of entire epiphytic and epilithic frond complements of 119 thalli from harvest beaches showed no difference in mean size of the largest fronds, and no difference in frond number per holdfast when epiphytic and epilithic thalli were compared.

• Journal of Nutrition and Health
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• v.24 no.5
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• pp.450-457
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• 1991

The iron status of 57 female college students was evaluated by measurements of hemoglobinCHb). hematocritCHct) and serum ferritin(Ferritin). Mean values for Hb, Hct and Ferritin were $13.9\pm$ 0.96g/dl, $41.4\pm$ 2.85% and $20.7\pm$ l5.5ng/mL respectively. Ferritin as well as Hb. Hct were not statistically different from normal distribution. although ferritin were skewed to the right. The prevalence of anemia defined by Hb < 12g/dI. Hct ~36 % and Ferritin <12ng/ml were found to be 5.3, 10.3 and 36.8%, respectively. By using Hb as a screening tool at a cutoff point of 12g/dI. 2.8% of healthy subjects will be incorrectly classified as anemic and 90.5 % of anemic as healthy. Sensitivity and specificity were calculated at various cutoff points of Hb and Hct. The estimates of sensitivity and specificity allow Hb 14.0g/dl as cutoff point for good predictor of anemia.

• The Journal of the Korean life insurance medical association
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• v.3 no.1
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• pp.103-141
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• 1986

The present study was undertaken to establish the decision standard of builds for the insured by using the ratio of weight-for-height as build index. Materials being examined were the ratio of weight-for-height being calculated from the actually measured heights and weights of a total of 15,838 insured persons who were examined medically at Honam Medical Department of Dong Bang Life Insurance Company, Ltd. from June, 1979 to September, 1985. The ratio of weight-for-height is calculated by the following formula. The ratio of weight-for-height(%)=$\frac{weight(kg){\times}100}{\{height(cm)-100\}{\times}0.9(kg)$ The results were as follows: 1. The distribution of the ratio of weight. for-height of the 15,838 insureds follows Log normal distribution being skewed to the left(the direction of underweight). 2. The ratio of weight-for-height were Log transformed to lead to a sym metrical pattern of distribution in which statistical rules are known to be applied more exactly. Thereafter, the establishment of dicision standard of builds was undertaken by using the log of the ratio of weight-for-height as build index. Through all ages in male, the ratio of weight-for-height indicating the range of standard lives including slight overweighted and underweighted lives besides normal lives is 80-130%, and corresponds to $"M-2{\delta}"-"M+1.5{\delta}"$ and to $M{\pm}20%$ ; in female, 85-135%, and corresponds to $"M-2{\delta}"-"M+1.5{\delta}"$ and to $M{\pm}20%$. Through all ages in male, the ratio of weight-for-height indicating the initial level of super-overweighted and super-underweighted lives is 130-150% and 75-80%,and corresponds to $M+3{\delta}\;and\;M-3{\delta}$ and to M+40% and M-25% respectively;in female, 140-160% and 75-80%, and corresponds to $M+3{\delta}\;and\;M-3{\delta}$ and to M+40%-+50% and M-25% respectively. 3. Author's rating table model for builds(a table of weight per height) is proposed. On the table, the ratings for builds, i. e. standard, super-weighted and super-underweighted lives, are listed.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.155-163
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• 1998

The purpose of this study was to determine the association between blood lipids, fibrinogen, fasting blood sugar, lifestyle-related factors and lipoprotein(a). This study was performed with 140 healthy adults (male:80, female:60) among the teachers in primary, middle, and high school in Seoul in November 1996. Lipoprotein(a) concentration was measured with an enzyme-linked-immunosorbents assay(ELISA), and the results showed that the distribution was highly skewed and the average concentrations of male and female were $16.94{\pm}12.70\;mg/dL\;and\;17.92{\pm}7.58\;mg/dL$, respectively. The percentage of subject with lipoprotein(a) concentrations higher than 30 mg/dL was 26.4%. Univariate analysis showed significant association between lipoprotein(a) and age, alcohol, meat, and NaCl consumption (p<0.05). In multivariate analysis, lipoprotein(a) correlated positively with age (p<0.05) and meat consumption (p<0.01). These data suggest that lifestyle-related factors may affect the lipoprotein(a) concentration regarded as a risk factor of atherosclerosis disease.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.136-138
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• 2005

무선 브로드캐스트 환경에서는 모바일 클라이언트의 제한된 배터리와 클라이언트에서 서버로의 제한된 상향 대역폭 등의 문제로 기존의 동시성 제어 기법을 그대로 사용할 수 없다. 이런 문제를 해결하고자 많은 동시성 제어 기법들이 연구되어 왔는데, 지금까지 제안된 기법들은 편향된 데이터의 접근 패턴을 반영한 브로드캐스트 환경을 고려하지 못하고 있다. 무선 브로드캐스트 환경에서 서버는 일반적으로 모바일 클라이언트의 접근 패턴을 고려하여 편향된 접근 빈도를 갖는 데이터 아이템을 브로드캐스트 한다. 본 논문에서는 무선 브로드캐스트 환경에서 편향된 데이터 접근 패턴을 고려한 동시성 제어 기법을 제안한다. 제안하는 기법은 브로드캐스트 디스크 모델에서 전체 메이저 브로드캐스트 주기마다. 모바일 트랜잭션을 위한 제어 정보를 보내는 것이 아니라 일정한 마이너 브로드캐스트 주기마다. 제어 정보를 전송한다. 이는 접근 빈도가 놓은 데이터가 갱신된 경우 갱신된 내용을 마이너 그룹마다 반영하므로 읽기 전용 트랜잭션이 접근하는 데이터가 최신 정보임을 보장할 뿐만 아니라 갱신 트랜잭션이 최종 검증을 위해서 상향 통신 대역폭을 이용하는 횟수를 줄이고, 보다. 빠른 재실행을 통해 모바일 트랜잭션의 평균 응답시간을 줄여줄 수 있다. 또한 모바일 트랜잭션의 요청이 편향된 경우, 반복적인 트랜잭션의 중단, 재실행으로 인한 성능 저하를 개선하고자 정적 백오프 기법을 이용하여 모바일 트랜잭션 간 충돌 가능성을 줄여준다. 마지막으로 시뮬레이션을 통해 기존의 기법들에 비해 평균 접근 시간, 상향 통신 대역폭 등의 사용량이 현저히 줄어드는 것을 보임으로써 제안하는 기법의 성능을 검증한다.한 평균 access time을 최소화하는 동시에 클라이언트들의 제한된 에너지 소비를 최소화하는데 목적이 있다. 제안기법에 대한 평가는 수학적 분석을 통해 HIDAF 기법과 기존의 브로드캐스트 기법의 성능을 비교 분석한다.하였으나 사료효율은 증진시켰으며, 후자(사양, 사료)와의 상호작용은 나타나지 않았다. 이상의 결과는 거세비육돈에서 1) androgen과 estrogen은 공히 자발적인 사료섭취와 등지방 침적을 억제하고 IGF-I 분비를 증가시키며, 2) 성선스테로이드호르몬의 이 같은 성장에 미치는 효과의 일부는 IGF-I을 통해 매개될 수도 있을을 시사한다. 약 $70 {\~} 90\%$의 phenoxyethanol이 유상에 존재하였다. 또한, 미생물에 대한 항균력도 phenoxyethanol이 수상에 많이 존재할수록 증가하는 경향을 나타내었다. 따라서, 제형 내 oil tomposition을 변화시킴으로써 phenoxyethanol의 사용량을 줄일 수 있을 뿐만 아니라, 피부 투과를 감소시켜 보다 피부 자극이 적은 저자극 방부시스템 개발이 가능하리라 보여 진다. 첨가하여 제조한 curd yoghurt는 저장성과 관능적인 면에서 우수한 상품적 가치가 인정되는 새로운 기능성 신제품의 개발에 기여할 수 있을 것으로 사료되었다. 여자의 경우 0.8이상이 되어서 심혈관계 질환의 위험 범위에 속하는 수준이었다. 삼두근의 두겹 두께는 남녀 각각 $20.2\pm8.58cm,\;22.2\pm4.40mm$으로 남녀간에 유의한 차이는 없었다. 조사대상자의 식습관 상태는 전체 대상자의 $84.4\%$가 대부분

• Journal of Nutrition and Health
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• v.49 no.1
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• pp.28-35
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• 2016

Purpose: Vitamin D status is associated with several chronic diseases related to obesity. In this study, we evaluate the nutritional status of vitamin D and its relation to obesity indices in Korean women. Methods: A total of 156 healthy women participated. Vitamin D status (serum $25-OH-vitamin\;D_3$ level) and obesity indices (body mass index, body fat mass, waisthip ratio, and body fat percentage etc.) and serum lipid profiles and serum adipokine (leptin and adiponectin) levels were analyzed. Results: The $25(OH)D_3$ level showed an extremely skewed distribution from 4.1 ng/ml to 24.4 ng/ml and mean $25(OH)D_3$ level was $9.0{\pm}4.0ng/ml$. With cut-off level for vitamin D deficiency (< 12.0 ng/ml), insufficiency (12-19.9 ng/ml) and sufficiency (${\geq}20ng/ml$), 77.6%, 19.2%, and 3.2% of subjects showed vitamin D deficiency, insufficiency, and sufficiency status, respectively. The $25(OH)D_3$ level showed positive correlation with weight (r = 0.2461, p < 0.01), body mass index (r = 0.2913, p < 0.001), body fat contents (r = 0.1691, p < 0.05), fat free mass (r = 0.2330, p < 0.01), and waist hip ratio (r = 0.1749, p < 0.05) after adjusted by age. The $25(OH)D_3$ level showed no significant correlation with serum lipid profiles and adipokine levels. Conclusion: Most subjects (76.6%) in this study, who had a vitamin D deficient status and serum $25(OH)D_3$ level, showed positive correlation with several obesity indices, however further research based on a large Korean population is needed to confirm the relationship.