• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권5호
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• pp.295-304
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• 2004

This paper deals with characteristic analysis method using d-q axis equivalent circuit considering iron loss in a single-phase line-start permanent magnet synchronous motor. The iron loss resistance to account for the iron loss is included in the equivalent circuit to improve the modeling accuracy. Furthermore, for the improved calculation of the iron loss, the iron loss is calculated from the magnetic flux density by 2-dimensional finite element method. The result is represented as the iron loss resistance and connected in parallel with the total induced voltage. Therefore, the currents can be expressed as the summation the output current with the current corresponding to the iron loss. Finally, the steady state characteristic analysis results are compared with the experimental results to verify this approach.

• 대한지역사회영양학회지
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• 제8권1호
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• pp.26-32
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• 2003

This study was designed to assess the nutritional iron status and anemia of middle school girls. Three-hundred-fifty- three female subjects in Ulsan metropolitan city were evaluated using a questionnaire, and hematological indices. The average height and weight of the respondents were 157.19 $\pm$ 5.57 cm and 51.06 $\pm$ 9.42 kg respectively. The average Body Mass Index (BMI, $kg/m^2$) was 20.63 $\pm$ 3.23, which was within the normal range. With regard to clinical symptoms, the greatest number of respondents reported that they experienced 'decreased ability to concentrate'. The total caloric intake of each subject was 1743.28 $\pm$ 343.47 kcal(83.01% of the Korean RDA) and the calcium intake was 634.98 $\pm$ 201.43 mg (79.37% of the Korean RDh) . The mean daily intake of iron was 14.76 : 4.36 mg (92.25% of the Korean RDh) and the heme iron intake was 6.12 $\pm$ 2.30 mg, which was 41.5% of the total iron intake. The average hemoglobin (Hb) concentration of the subjects was 13.24 $\pm$ 1.01 g/dl, and the average hematocrit (Hct) level was 37.79 $\pm$ 4.10%. The transferrin saturation {TS (%)} was 19.41 $\pm$ 9.21%, and the ferritin level was 26.26 $\pm$ 18.60 ng/ml. The iron deficiency anemia among the subjects was estimated at 6.1% by using Hb (< 12 g/ml), 20.5% by using Hct (< 36%), 30.8% by using 75 (< 14%) , and 23.1% by using ferritin (< 12 ng/ml) The total iron binding capacity (TIBC) showed a negative correlation with the Hb, iron, ferritin and 75. With regard to the correlation between blood biochemistry and clinical symptoms related to anemia, the Hb concentration was negatively correlated with 'pale face'(p < 0.05) . In addition, the level of iron was significantly and negatively correlated with 'poor memory' (p<0.01) and the ferritin concentration was negatively correlated with 'no appetite '(p < 0.05) ,'pale face (p < 0.05) . These results suggest that the prevalence of iron deficiency among middle school girls is very high; therefore, guidelines on dietary support and nutritional education to improve their dietary iron status should be provided.

• 한국식품영양과학회지
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• 제27권2호
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• pp.296-304
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• 1998

The effects of common Korean dietary fiber-rich foods(dried sea mustard, Lentinus edodes and Korean radish leaves) on total gut transit time of diet, serum cholesterol level and mineral apparent absorption ration and tissue level were investigated. Twenty eight male were divided into 4 groups and were fed a control diet(containing 2% cellulose) and three fiber supplementary diet mixed with 10% of the above dietary fiber rich foods for 4 weeks, respectively. Body weight gain and food efficiency ration were not affected by the supplementary diet of fiber but the total gut transit time of diet was shortened in all dietary fiber groups. The Lentinus edodes reduced significantly serum total cholesterol and increased the HDL-cholesterol/total cholesterol ratio at 4th week without and effect on calcium and iron apparent absorptions and tissue levels of the minerals. Radish leaves decreased significantly iron apparent absorption ration with a tendency to increase iron retention in spleen and did not alter serum cholesterol level. Serum cholesterol concentration and calcium and iron apparent absorptions were not significantly altered by the ingestion of sea mustard, while it had more soluble dietary fiber than mushroom and radish leaves.

• Preventive Nutrition and Food Science
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• 제8권1호
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• pp.70-74
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• 2003

This study investigated the relationship of Helicobacter pylori (H. pylori) infection to iron-deficiency anemia in high school girls. Four hundred and fourty-five subjects resided in Ulsan City in Korea were evaluated by questionnaire or blood analysis for serum indicators of iron status, daily nutrient intakes, symptoms of anemia, and H. pylori IgG antibody status. In H. pylori infected subjects, total energy intake of was 1534.14±350.81 kcal (73.0% of the Korean RDA), the iron intake of subjects was 11.38±3.90 mg (71.1% of Korean RDA) and calcium intake was 467.63±175.96 mg (58.3% of the Korean RDA). Carbohydrate (p < 0.05), vitamin A (p < 0.05), vitamin C (p < 0.01) intakes were significantly lower in infected subjects than in non-infected subjects. The prevalence of anemia (hemoglobin (Hb) < 12 g/dL.) in H. pylori infected subjects was 22.7% as compared to 14.7% in non-infected subjects. The mean serum ferritin of infected subjects (21.71±21.50 ng/mL) was significantly lower than in non-infected subjects (p < 0.05) (as was the mean Hb concentration (12.54±1.51 g/dL) and hematocrit (37.99±3.64%)). Total iron binding capacity (TIBC) of H. pylori infected subjects (449.09±78.23 ㎍/dL) was significantly higher than that of non-infected subjects (432.99＋76.15 ㎍/dL) (P < 0.05). The levels of iron, red blood cell (RBC) and transferrin saturation were similar in infected and non-infected subjects. Two symptoms of anemia, 'pale face (p < 0.01)' and 'decreased ability to concentrate (p < 0.005)', were significantly higher in H. pylori infected subjects than in non-infected subjects. High school girls are known to be more vulnerable to iron deficiency than other age groups, and this research demonstrates that infection with H. pylori increases their risk of iron-deficiency anemia.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권2호
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• pp.16-24
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• 2014

To test the potential effects of extracellular electron shuttles (EES) on the rate and extent of heavy metal release from contaminated soils during microbial iron reduction, we created anaerobic batch systems with anthraquinone-2,6-disulfonate (AQDS) as a surrogate of EES, and with contaminated soils as mixed iron (hydr)oxides and microbial sources. Two types of soils were tested: Zn-contaminated soil A and As/Pb-contaminated soil B. In soil A, the rate of iron reduction was fastest in the presence of AQDS and > 3500 mg/L of total Fe(II) was produced within 2 d. This suggests that indigenous microorganisms can utilize AQDS as EES to stimulate iron reduction. In the incubations with soil B, the rate and extent of iron reduction did not increase in the presence of AQDS likely because of the low pH (< 5.5). In addition, less than 2000 mg/L of total Fe(II) was produced in soil B within 52 d suggesting that iron reduction by subsurface microorganisms in soil B was not as effective as that in soil A. Relatively high amount of As (~500 mg/L) was released to the aqueous phase during microbial iron reduction in soil B. The release of As might be due to the reduction of As-associated iron (hydr)oxides and/or direct enzymatic reduction of As(V) to As(III) by As-reducing microorganisms. However, given that Pb in liquid phase was < 0.3 mg/L for the entire experiment, the microbial reduction As(V) to As(III) by As-reducing microorganisms has most likely occurred in this system. This study suggests that heavy metal release from contaminated soils can be strongly controlled by subsurface microorganisms, soil pH, presence of EES, and/or nature of heavy metals.

• Food Quality and Culture
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• 제1권1호
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• pp.46-57
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• 2007

The purpose of the present study was to examine the nutrient intake status of elderly dementia patients. We surveyed the dietary intake of 50 demented elderly patients receiving a regular diet, who were hospitalized in a geriatric hospital in Yongin, Gyeonggi-do. The average age of the subjects was $79.6{\pm}6.5$ for the males and $80.5{\pm}6.3$ for the females. The average heights were $169.5{\pm}6.0\;cm$ (males) and $154.6{\pm}5.2\;cm$ (females), and the average weights were $58.5{\pm}7.4$ (males) and $51.7{\pm}8.9\;kg$ (females). Depending on the type of dementia, the male patients showed significant differences in their intakes of vegetable protein, fiber, total iron, and non-heme iron between the Alzheimer's disease (AD) and the vascular dementia (VD) groups, and the female patients showed significant differences in their intakes of total protein, phosphorus, zinc, and vitamin $B_6$ between the two groups. The male patients showed significant differences in their intakes of animal-source calcium and carotene according to ability to self-feed. According to physical activity, the male patients showed significant differences in vegetable fat and vitamin A intake, and the females showed significant differences in their intakes of total protein, animal protein, fiber, ash, total calcium, vegetable-source calcium, animal-source calcium, phosphorous, total iron, non-heme iron, heme iron, sodium, vitamins $B_1$, $B_2$, $B_6$, niacin, vitamin C, folate, and potassium. We found that the patients consumed excessive protein, but low amounts of calcium, vitamin $B_2$, and folate. Also, the patients' physical activity abilities appeared to affect their nutrient intakes.

• 한국산학기술학회논문지
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• 제18권10호
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• pp.603-610
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• 2017

탄약을 포함한 다양한 산업 분야에서 사용되는 철강 재료는 부식에 취약하므로, 표면 그대로 사용하는 것은 바람직하지 않다. 따라서 도금, 도장, 화성처리와 같은 표면 처리 이후 사용하여야 하는데, 탄약 제조 과정에서는 주로 아연계 인산염 피막 처리가 사용되고 있다. 표면 처리 기법 중 하나인 아연계 인산염 피막은 금속 표면을 화학적으로 처리하여 안정성이 높은 화합물 층을 표면에 고착시키는 방법으로, 크게 도장 하지용 경인산염 피막과 부식 방지용 중인산염 피막으로 나뉘어지는데, 아연계 인산염 피막은 전산도, 철 함량과 같은 여러 가지 인자에 의해 피막의 품질과 내식성이 결정된다. 본 연구에서는 전산도 및 철 함량이 탄약 부식 방지 목적으로 사용되는 아연계 중인산염 피막의 중량 및 내식성에 미치는 영향에 대하여 알아보았다. 철 함량에 따라 피막의 구조가 치밀해지며, 내식성이 향상되는 결과를 확인할 수 있었으나, 전산도는 피막의 두께와 중량에만 영향을 주고 내식성에는 큰 영향을 주지 못하였다. 위 결과를 토대로 탄약 제조 과정에서 사용되는 인산염 피막 처리 공정의 최적 제어 수준을 제시하였다.

• Journal of Nutrition and Health
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• 제35권9호
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• pp.943-951
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• 2002

This study was designed to investigate the effects of iron supplementation and nutrition education on the iron status and anemia of high school girls. The subjects resided in Ulsan city in Korea and were already diagnosed as having anemia or iron deficiency. Over a period of three months, one iron tablet (80 mg Fe as ferrous sulfate/day) was administered to the iron deficient subjects and two tablets (160 mg Fe as ferrous sulfate/day) were administered to the anemia subjects. The average height and weight of anemia subjects were 161.24 $\pm$ 4.50 cm and 50.87 $\pm$ 5.86 kg, respectively. The average BMI (kg/$m^2$ )was 19.58 $\pm$ 2.03 and the PIBW(percent ideal body weight) were 92.52 $\pm$ 9.84%. Except for vitamin A and vitamin C intakes, the intake levels of all other nutrients were below the RDA. Total calorie intakes of anemia subjects were 73.5% of RDA. The iron intakes of subjects from food were 69. 1% of RDA and the Ca intakes were 59.1% of RDA. The basal hemoglobin(Hb) concentration of anemia subjects averaged 10.77 $\pm$ 1.33 g/dl, and this increased significantly (p < 0.001) to 12.12 $\pm$ 1.08 g/dl, after iron supplementation. The basal ferritin, and transferrin saturations ｛TS (%)｝of anemia subjects were 12.51 $\pm$ 15.19 ng/$m\ell$ and 8.43 $\pm$ 7.56%, respectively, and these significantly increased to 20.59 $\pm$ 22.39 ng/$m\ell$ and 15.56 $\pm$ 12.87%, respectively. The level of total iron binding protein (TIBC) significantly decreased from the initial 486.80 $\pm$ 70.16 $\mu\textrm{g}$/dl to 417.86 $\pm$ 67.73 $\mu\textrm{g}$/dl (p < 0.001) after iron supplementation. For the iron deficiency subjects, the ferritin, iron and TS(%) levels were increased significantly (p < 0.001) and the TIBC levels were significantly (p <0.001) decreased after iron supplementation. Anemia symptoms such as 'Feeling blue (p<0.05)', 'Decreased ability to concentrate (p<0.001)' and 'Poor memory (p<0.05)' improved significantly after iron supplementation in the anemia subjects. The number of tablets administered was positively correlated with changes in serum hemoglobin (t=0.194, p< 0.01), serum ferritin (t=0.181, p<0.01), TS(%) (t=0.141, p<0.05), and hematocrit (t=0.254, p<0.01), and was negatively correlated with changes in TIBC (t=-0.143. p<0.05) and red cell distribution width (RDW, t=-0.140, p<0.05). In conclusion, daily iron supplementation was effective in improving the iron status and reducing symptoms of anemia in high school girls. (Korean J Nutrition 35 (9) : 943~951,2002)

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제5권2호
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• pp.129-135
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• 2002

목 적: 철분 결핍에 노출되기 쉬운 사춘기 소아에서 H. pylori 감염과 철 결핍성 빈혈의 상관 관계를 알아보고자 하였다. 방 법: 혈색소, 혈청 철, 총 철 결합능, 혈청 페리틴, H. pylori에 대한 변역글로붙린 G 항체를 937명(남자 475명, 여자 462명)을 대상으로 측정하였다. 이들의 연령은 10세에서 18세였다. H. pylori 감염의 유병률은 빈혈, 저 페리틴혈증, 철 결핍, 철 결핍성빈혈 유무에 따라 두 군으로 비교하였다. 또한 H. pylori 감염 유무에 따라 혈색소, 혈청 철, 총 철 결합능, 트랜스페린 포화도, 혈청 페리틴의 농도를 비교하였다. 결 과: 빈혈, 철 결핍, 철 결핍성 빈혈, H. pylori 감염에 대한 각각의 유병률은 8.1%, 9.1%, 3.1%, 20.8%였다. 빈혈, 저 페리틴혈증, 철 결핍 각각의 군에서 H. pylori 감염율은 34.2%, 29.5%, 35.3% 이었고, 빈혈이 없는 군에서는 H. pylori 감염률이 19.6%, 저 페리틴혈증이 없는 군은 19.2%, 철 결핍성 빈혈이 없는 군은 19.4%이었다. H. pylori 감염율은 철 결핍성 빈혈군에서 44.8%, 정상군에서 20.0%이었다. 혈색소와 철분 농도는 유의한 차이가 없었지만 혈철 페리틴 농도는 H. pylori 감염군에서 유의하게 감소하였다. 결 론: H. pylori 감염은 사춘기 청소년에서 철결핍과 관련있을 것으로 생각된다.

• Journal of Nutrition and Health
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• 제26권6호
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• pp.692-702
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• 1993

To evaluate iron nutritional status and to compare biochemical indices used for evaluation of iron nutriture, fasting blood sample was taken from 96 Korean female college student and hemoglobin(Hb) concentration, hematocrit(Hct), serum iron, total iron binding capacity(TIBC) and serum ferritin concentration were measured and transferrin(TF) saturation was calculated. Prevalence of iron deficiency varied from 4.2% when judged from Hb concentration and Hct to 38.5% and 40.6% when TIBC and serum ferritin concentration were used. TIBC was negatively correlated with serum ferritin(r=0.4561, p<0.001), while other indices showed positive but less significant correlations(p<0.05). Regarding iron status judged by serum ferritin was regarded as true iron status, the present cutoff points of Hb, Hct, serum iron, TF saturation were very insensitive in identifying the subjects with iron deficiency. Only TIBC was suitable for detecting iron deficiency in the study subjects. It is concluded from the study results that iron deficiency in young Korean adult women would be significantly underestimated with presently used biochemical measurements except TIBC and new cutoff points of these indices were proposed based on sensitivity, specificity measured prevalence, and positive and negative predictive values.