• Proceedings of the KSCN Conference
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• 2000.11a
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• pp.62-62
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• 2000

• Korean Journal of Human Ecology
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• v.4 no.1
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• pp.36-45
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• 2001

This study was performed to determine the changes of maternal iron status during pregnancy cross sectionally, and to evaluate the appropriateness of the cut-off points of hemoglobin (Hb). hematocrit (Hct), serum transferrin receptor (sTfR) and sTfR : ferritin ratio for assessing iron deficiency status based on serum ferritin level (< 12${\mu}g$/L). Serum Hb concentrations in the first trimester were significantly higher (p < 0.05) than those in the second and third trimester. Serum levels of iron and ferritin in the third trimester were significantly lower (p < 0.05) than those in the first and second trimester. On the other hand, sTfR:ferritin ratios in the third trimester were significantly higher (p < 0.05) than those in the first and second trimester. sTfR concentrations did not change significantly during pregnancy. The appropriate cut-off points of Hb were 11.5g/dL for whole period of pregnancy. 12.0g/dL for 1st trimester. and 11.5g/dL for both 2nd and 3rd trimester. The good cut-off points of Hct were 34% for whole period of pregnancy. 36% for 1st trimester. and 34% for both 2nd and 3rd trimester The suitable cut-off points of TIBC were 400${\mu}g$/dL for whole period of pregnancy. 360${\mu}g$/dL for 1st trimester, and 400${\mu}g$/dL for both 2nd and 3rd trimester. Any cut-off point of sTfR could not be selected because of its low sensitivity and specificity. The proper cut-off point of sTfR : ferritin ratio was 600 or 650 for all the periods determined except the first trimester. In conclusion, there were no reliable cut-off levels of sTfR and those of sTfR : ferritin ratio showed low specificity. The cut-off values of Hb and Hct for assessing iron deficiency were slightly higher than the values used to evaluate anemia. Thus, if appropriate cut-off levels were applied, Hb. Hct, or TIBC might be useful indices for evaluating iron deficiency as well as anemia.

• Clinical and Experimental Pediatrics
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• v.58 no.1
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• pp.15-19
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• 2015

Purpose: Soluble transferrin receptor (sTfR) is a truncated extracellular form of the membrane transferrin receptor produced by proteolysis. Concentrations of serum sTfR are related to iron status and erythropoiesis in the body. We investigated whether serum sTfR levels can aid in diagnosis and treatment of iron deficiency anemia (IDA) in children. Methods: Ninety-eight patients with IDA were enrolled and were classified according to age at diagnosis. Group 1 comprised 78 children, aged 6-59 months, and group 2 comprised 20 adolescents, aged 12-16 years. Results: In group 1, patients' serum sTfR levels correlated negatively with mean corpuscular volume; hemoglobin (Hb), ferritin, and serum iron levels; and transferrin saturation and positively with total iron binding capacity (TIBC) and red cell distribution width. In group 2, patients' serum sTfR levels did not correlate with ferritin levels and TIBC, but had a significant relationship with other iron indices. Hb and serum sTfR levels had a significant inverse relationship in both groups; however, in group 1, there was no correlation between Hb and serum ferritin levels. In 30 patients of group 1, serum sTfR levels were significantly decreased with an increase in Hb levels after iron supplementation for 1 month. Conclusion: Serum sTfR levels significantly correlated with other diagnostic iron parameters of IDA and inversely correlated with an increase in Hb levels following iron supplementation. Therefore, serum sTfR levels can be a useful marker for the diagnosis and treatment of IDA in children.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.435-440
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• 2009

Purpose : The concentration of soluble transferrin receptor (sTfR) is estimated as an iron parameter to evaluate erythropoiesis and iron status. The aim of our study is to evaluate the correlation between sTfR concentration and inflammatory parameters and to distinguish iron deficiency anemia from anemia of inflammation. Methods : One hundred and forty-four infants younger than two years of age who visited Gyeongsang University Hospital for 7 years from 2000 to 2006 were enrolled. Patients who had hemoglobin (Hb) <11 g/dL and ferritin <12 mg/L were excluded. Routine hematologic lab, serum ferritin, sTfR, and inflammatory markers [C-reactive protein(CRP), interleukin-6(IL-6), and absolute neutrophil count (ANC)] were investigated. Results : In all patients, the sTfR concentration showed a correlation with Hb, ferritin, MCV, and ANC, but not with CRP and IL-6. In multiple regression models, positive correlations were found between sTfR concentration and IL-6 (r=0.078, P=0.043), and negative correlations were found between sTfR concentration and ANC (r=-0.117, P=0.033) and MCV (r=-0.027, P=0.009). Conclusion : sTfR concentration was influenced by inflammatory parameters. Therefore, sTfR does not appear to be a useful parameter for discriminating between iron deficiency anemia and anemia of inflammation in infants.

• Korean Journal of Community Nutrition
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• v.5 no.4
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• pp.754-754
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• 2000

• Journal of Community Nutrition
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• v.4 no.1
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• pp.3-11
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• 2002

The purpose of this study is to evaluate the iron nutritional status by investigating dietary intake and analyzing the hematological iron status indices including serum transferrin receptor (sTfR) in 8 to 28 month old infants md young children taking supplementary foods. The nutrient intake of 60 healthy infants and young children from 8 to 24 months of age was investigated by means of a 24-hour recall method, and the subjects were divided into 2 groups (8- 12 months and 13-28 months) according to age. Venous blood samples from these groups were collected and measured for the following : hemoglobin(Hb), hematocrit(Hct) , mean corpuscular volume (MCV), mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration (MCHC), serum ferritin, serum iron, total iron binding capacity (TIBC), and sTfR. Anemia is defined as hemoglobin < 11g /dl , serum ferritin level < 10ng1m1 for iron deficiency , serum transferring receptor(sTfR) > 4.5mg / 1 for iron deficient erythropoiesis. Total daily calorie intake was 934.6 ${\pm}$ 284.5kcal (98.32% of RDA) on average. Average daily iron intake in infants aged 8 to 12 months was 8.92 ${\pm}$ 3.32mg. The mean daily iron intake in infants aged 13 to 28 months was 7.15 ${\pm}$ 3.35mg (90% of Recommended Dietary Allowance, RDA). Mean values for Hb, Hct sew ferritin and sTfR were 12.10 ${\pm}$ 0.77g141,36.02 ${\pm}$ 2.31%,20.91 ${\pm}$ 11.58ng/m1 and 3.78 ${\pm}$ 1.47mg /1, respectively. In the young children from 13 to 28 months of age, the prevalence of anemia was 5.6%. The prevalence of iron deficiency was 9.5% in those from 8 to 12 months of age, and 27.8% in those from 13 to 28 months of age. The prevalence of iron deficient erythropoiesis was 16.7% in infants aged 8 to 12 months and 44.4% in those aged 13 to 28 months. The prevalence of both serum ferritin level < 10ng/m1 sTfR > 4.5mg/1 was 22% in the young children aged 13 to 28 months. The measureand ment of sTfR may be a promising new tool in diagnosis of iron deficiency in early childhood when the iron deficiency is prevalent. It seems appropriate to emphasize nutritional education and evaluation to promote the iron nutritional status of infants and young children.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.283-290
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• 2000

The present study was carried out to investigate the blood markers of Cheju horses. The blood protein types (biochemical polymorphism) were tested from 73 Cheju native horses (CNH) and 118 Cheju racehorses(CRH) by horizontal polyacrylamide gel electrophoresis (HPAGE), isoelectric focusing (IEF) and starch gel electrophoresis (SGE). At the same time, their phenotypes and gene frequencies were studied. The biochemical polymorphism phenotypes observed with high frequency were A1B-KK(97.3%), ALB-AB(49.3%), AP-SS(100%), ES-II(30.1%), GC-FF(87.7%), HB-BIBI(49.3%), TF-F2R(41.1%), TF-EF2(8.2%), PGD-FF(97.3%), PGM-SS(50.7%), GPI-II(74.0%) in CNH, While A1B-KK(99.2%), ALB-BB(50.8%), AP-SS(99.2%), ES-II(42.4%), ES-IS(14.4%), GC-FF(95.8%), HBB-IB II(39.8%), TF-F2R(21.2%), PGD-FF(77.1%), PGD-SS(4.3%), PGM-SS(72.9%), GPI-II(90.7%) in CRH. Alleles observed with high frequency were $AlB^{K}$(0.986), $ALB^{B}$(0.616), $AP^{S}$(1.000), $ES^{I}$(0.479), $ES^{F}$(0.274), $GC^{F}$(0.938), $GPI^{I}$(0.856), $HB^{BI}$(0.685), $PGD^{F}$(0.993), $PGM^{S}$(0.753), $TF^{F2}$(0.404), $TF^{R}$(0.397) in CNH and $AlB^{K}$(0.996), $ALB^{B}$(0.720), $AP^{S}$(0.996), $ES^{I}$(0.661), $ES^{F}$(0.203), $GC^{F}$(0.979), $GPI^{I}$(0.936), $HB^{BI}$(0.534), $PGD^{F}$(0.864), $PGM^{S}$(0.852), $TF^{F2}$(0.428), $TF^{R}$(0.272) in CRH. $TF^{E}$(0.041) allele and silent gene($ES^{I{^*}}$ : 0.014) were observed in CNH. The mean heterozygosity in CNH and CRH was observed 0.2974 and 0.2864, respectively.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.435-437
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• 2006

KSTAR (Korea Superconducting Tokamak Advanced Research) 장치는 Tokamak 개념의 핵융합 연구 장치로서 플라즈마를 가두기 위한 자장을 발생하는 토로이달 자장(Toroidal Field, TF) 코일과 플라즈마 발생 및 형상 조정을 위한 폴로이달 자장 (Poloidal Filed, PF) 코일로 구성되며, 초전도 코일을 이용한다. TF코일의 전원장치로는 40 kA급의 안정된 직류 전원장치가 필요하며, PF 코일의 전원장치로는 빠른 전류상승 및 피드백 기능을 갖춘 정밀 대전류 전원을 필요로 한다. 또한 초전도 코일의 ??????치현상 발생 시 코일과 전원장치 보호를 위한 대전류 직류 차단시스템을 필요로 한다. KSTAR 장치의 설계에 의하면 상하 7쌍의 초전도 PF 코일에 약 1MA/sec급의 고속 전류구동을 운전 시나리오에 따라 인가하여 핵융합 연구를 위한 플라즈마를 생성한다. 본 논문은 TF 및 PF 코일에 대전류를 인가하기 위해서 개발된 전원장치 (Power Supply, PS)에 관한 연구이다.

• The Journal of Korean Association of Computer Education
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• v.22 no.3
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• pp.67-78
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• 2019

The purpose of this study is to explore information ethics issues based on academic big data from Web of Science (WoS) and to provide implications for information ethics education in informatics subject. To this end, 318 published papers from WoS related to information ethics were text mined. Specifically, this paper analyzed the frequency of key-words(TF, DF, TF-IDF), information ethics issues using topic modeling, and frequency of appearances by year for each issue. This paper used 'tm', 'topicmodel' package of R for text mining. The main results are as follows. First, this paper confirmed that the words 'digital', 'student', 'software', and 'privacy' were the main key-words through TF-IDF. Second, the topic modeling analysis showed 8 issues such as 'Professional value', 'Cyber-bullying', 'AI and Social Impact' et al., and the proportion of 'Professional value' and 'Cyber-bullying' was relatively high. This study discussed the implications for information ethics education in Korea based on the results of this analysis.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.2
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• pp.185-200
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• 2023

The Korea Augmentation Satellite System (KASS) is the first satellite navigation enhancement system in Korea developed in compliance with international standards. Technologies accumulated during the development process should be spread to industries such as academia and serve as the basis for developing the domestic satellite navigation field. This paper introduces the development process from design to implementation, testing, and verification of KASS control systems (KCS). First, development standards, milestones, requirements, and interface standards are presented as KCS development methods, and major functional design, physical design, and hardware/software implementation are described based on the allocated requirements. Subsequently, the verification environment, procedures, and results of the development product are covered and the developed operational and maintenance procedures are described. In addition, based on the experience gained through the development, suggestions were made for beneficial technology development and organization when promoting satellite navigation projects in the future. Since this work has important historical value for the development of domestic satellite navigation, it is expected that the development results will be shared with academia and industry in the future and be used as basic data for similar development.