• 천문학회보
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• 제43권2호
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• pp.29.1-29.1
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• 2018

With their complex structure that includes a thin disc, spiral arms, and often a bar, galaxies have been regarded as something beyond the human perceptions. Hence, the studies on galaxy formation in the 20th century have almost exclusively based on schematic scenarios. With markedly improved knowledge on cosmology over the last couple of decades, we have finally acquired a base from which galaxy formation can be studied from the first principles of physics. I review the modern history of the study of galaxy formation and present some preliminary results from the most recent numerical simulations that provide more realistic pictures of galaxy formation than was available ever before. In terms of galaxy formation, the age of scenarios is fading away, while the age of physical understanding is rising over the horizon.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.231-236
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• 2000

In this study, to present the use of the blase furnace slag fly ash derived from a large amount of the industrial products with the early strength reduction of it prevented, the initial strength is measured after a large quantity of fly ash and the required stimulus agent for the high development of the initial strength was added in blast furnace slag cement. As the results, in spite of the much addition of fly ash in blast furnace slag, the long-age strength of blast furnace slag cement was able to be improved by a proper amount of stimulus agent, and was as high as that of ordinary portland cement.

• 천문학회보
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• 제45권1호
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• pp.50.3-50.3
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• 2020

We present deep UBVIc and Hα photometry for the young open cluster IC 1590 which is at the center of the HII region NGC 281. From Ha index, 39 Hα emission stars and 15 Hα emission candidates are selected. The reddening law toward IC 1590 is slightly abnormal (RV,cl = 3.6 ± 0.2). The distance modulus of IC 1590 obtained from the reddening-free (Q', QVλ) diagrams is 12.4 ± 0.1 mag (d = 3.02 ± 0.14 kpc), which is consistent with distance d = 2.91 ± 0.42 kpc from the parallax of Gaia DR2 catalogue within the error range. We also determined the age and mass function of IC 1590 using the stellar evolution models and PMS evolutionary tracks. The median age of PMS stars is 2.4 ± 2.2 Myr. The initial mass function (IMF) of IC 1590 is the Salpeter-type IMF with a slope of �� = -1.26 ± 0.14 for m > 1 M⊙ stars.

• 생명과학회지
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• 제9권2호
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• pp.182-193
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• 1999

SAMP6의 성별 및 가령에 따른 생물학적인 특성을 알아보기 위하여 3, 5, 18개월령의 SAMP6 암컷, 수컷의 체중, 장기중량, 혈액학적 및 혈액생화학적 수치, 골의 무게, 비중, 두께 및 골의 화학적 분석을 위해 인과 칼슘을 측정하였다. 1. 체중은 수컷에서 7개월령부터 감소를 나타내었으나, 암컷은 18개월령부터 체중이 감소되기 시작했다. 장기중량을 보면, 간, 신장, 폐의 중량은 수컷이 암컷보다 무거웠으며, 흉선은 암컷이 수컷보다 무겁게 나타났다. 2. 혈액학적 및 혈액생화학적 검사결과 백혈구수가 수컷이 암컷보다 높게 나타났으며, 적혈구수는 암컷이 높게 나타났다. GOT는 5, 7개월령에, BUN은 전체개월령에서 수컷이 암컷보다 높게 나타났다. alkaline phosphatase 활성은 3개월령과 비교하여, 전체 개월령에서 유의성있는 감소가 관찰되었다. 3. 골두께를 측정한 결과 대퇴골에서 암수 모두 7개월령 부터 골두께의 급격한 감소가 나타났다. Cortical thickness index를 측정한 결과 대퇴골에서 암수 모두 5개월령에서 최고치에 다다랐으며, 이후 계속 감소하였다. 4. 골의 칼슘량을 정한 결과, 대퇴골에서 암수 모두 5개월령에 칼슘량이 최고치에 달했으며, 이후 계속 감소하였고, 인량은 수컷에서 5개월령, 암컷에서는 7개월령에 최고치에 달하였고, 이후 계속 감소하였다. 결론적으로 본 실험에서 사용한 골다공증 모델동물인 SAMP6의 특성발현은 5개월 이후 동물에서 나타나고 있으며 따라서 이들 동물을 골다공증 약물 개발을 위한 약효검색에 이용할 때에는 5개월령 이후 7개월령의 동물을 사용하는 것이 바람직하며 본 실험에서 유의성 있는 특성발현이 나타난 골 두께 및 골의 칼슘과 인량, alkaline phosphatase 활성 측정등을 약효 검색에 사용할 수 있을것으로 사료된다.

• 한국가축번식학회지
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• 제9권2호
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• pp.124-132
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• 1985

The work was conducted to clarify the development of testes and histological changes of the Seminiferous tubules that is the Surface area, diameter, length of the tubules and the process of Spermatic cells growth in Seminal epithelium in relation to Sexual maturity of the meat-type cockerels. In addition the present experiments were planned to gain some basic data helpful for the study of reproductive physiology in meat-type cockerels and also to compare the histological changes Seminiferous tubules between egg and general purpose type cockerels. 1. The growth pattern of body weight, testes and comb was classified into four phase according to age. Body weight increased up to about 2kg at 2nd stage and to 4.3kg at 4th stage while at 3rd stage the growth rate of body weight was slower. The tests developed slowly until 22 weeks of age with no correlation to the growth of body weight. However, it grew rapidly afterwards, reaching 27.79$\pm$9.26gm and 42.46$\pm$5.33 gm at 24 and 28 weeks of age, respectively. The spermatozoa was seen first at 24 weeks of age. On the other hand, comb grew at similar rate to the testes, weighing on the average 21.78$\pm$6.48gm and 41.42$\pm$1.25gm at 24 and 28 weeks of age, respectively. 2. The areal rate of the Seminiferous tubules to interstitial tissues was 66%:34% at 2 weeks of age and the rate of the former increased in comparison to that of the latter as they grew older, becoming 94%:7% between at 24 weeks of age, when the testes weight increased rapidly too. 3. Diameter of Seminiferous tubules at 2 weeks of age was 42.76$\pm$1.04$\mu$m and then it gradually increased as the testes grew until 22 weeks of age, when it grew rapidly, increasing about 2.9 times of those of 2 weeks and at last increased up to 5 times at 24 weeks. 4. Length of Seminiferous tubules was 4.5cm at 2 weeks and then it was gradually increased. At 22 weeks old the length of tubules was icnreased rapidly being 321 meter and increased more than double, being 658 meter at 24 weeks old. 5. The cells of Seminal epithelium developed poorly and the number of cells were relatively few until 16 weeks old. Afterwards the cells increased rapidly in number and at 18 weeks, the number became twice of those of 16 weeks, reaching 140.43$\pm$43.6. At 24 weeks the cells increased more rapidly, reaching to 10 layers and Spermatozoa were first time seen.

• 수산해양기술연구
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• 제17권1호
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• pp.13-18
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• 1981

한국국적을 가진 일반화물선 30척과 원목운반선 15척의 외판부식도를 선령별로 조사한 결과는 다음과 같다. 1. 일반화물선 1) 전평균부식도는 어느 선령급에서나 경흘수선부가 가장 크다. 2) 선수미방향의 전평균부식도는 어느 선령급에서나 선수부가 중앙부나 선미부보다 크나, 큰 차이는 없다. 3) 깊이 방향의 부식도는 선령 16년 이하에서 건현부, 만재흘수선부, 하부만곡부, 경흘수선부의 순으로 크다. 또 35년에 있어 부식도는 경흘수선부와 만재흘수선부는 건현중앙부에 약 3배, 상부만곡부는 그것의 약 2배 되어 수선부가 가장 부식이 심함을 나타낸다. 2. 원목운반선 1) 전평균부식도는 어느 선령급에서나 상부만곡부가 가장 크다. 2) 선수미방향의 부식도는 어느 선령급에서나 선수부가 가장 크나, 큰 차이는 없다. 3) 깊이 방향의 부식도는 어느 선령급에서나 건현부가 가장 작고, 상부만곡부가 가장 커서 그 부식도는 건현부의 약 2배가 된다. 3. 일반화물선과 원목운반선. 원목운반선의 부식도의 전평균은 일반화물선의 그것의 약 3배나 된다.

• 대한가정학회지
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• 제42권8호
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• pp.169-185
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• 2004

This study was performed to investigate the characteristics of meal patterns among Koreans of different age groups. The study subjects consisted of preschool children (PC), elementary school children (EC), high school students (HS), college students (CS), and adults over 30 years old living in Seoul and the surrounding areas. A dietary survey was conducted using 24-hour recall method from 1996-1998 and data were collected from 2392 subjects. The subjects over 30 years old were classified as 30∼49 years, 50∼69 years, and over 70 years. EC, HS, and CS groups consumed less than 20％ of their total energy intake from breakfast. PC and EC consumed over 30％ of their energy from snacks. In all age groups, the proportion of subjects who skipped a meal was highest for breakfast and lowest for dinner. Especially, 31.4％ of the CS group skipped breakfast. Breakfast and snacks provided higher quality meals than the others when each meal was assessed by the index of nutritional quality (INQ). Especially, lunch of the HS group, each meal of the EC group and subjects over 70 years of age had a lower diet quality than the others did. The major snack items for PC, EC, HS, and CS groups were milk, ice cream, and snack cakes, but those for subjects over 30 years of age were fruits. The PC group obtained 35.5％ of their energy from snacks, but the proportion of snack energy decreased with increasing age. PC and EC groups obtained a great proportion of calcium, vitamin B2, fat, and cholesterol intake from snacks. Snack foods provided 53.2％, 42.4％, 45.4％, and 24.6％ of those nutrients, respectively, for the PC group and 54.2％, 43.5％, 37.4％, and 26.8％, respectively, for the EC group. These results suggested that each age group had specific meal patterns. Especially, breakfast and snack intake seemed to complement overall diet quality. However, more intervention is needed to improve overall dietary nutrition, e.g., efforts to decrease fat and cholesterol proportion and increase breakfast consumption. These dietary characteristics among different age groups present foundation data for the development of methods to resolve the nutritional problems of each age group.

• 자원환경지질
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• 제42권6호
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• pp.541-548
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• 2009

한반도 남동부에 위치한 동래온천은 우리나라의 대표적인 고온성 온천중의 하나이다. 동래온천수의 수질형태는 Na-Cl형이고, 상부의 일반 천부지하수는Ca(-Na)-$HCO_3$ 형으로서 서로 간에 연결성이 매우 미약하다. 이 논문에서는 동래 온천수의 $^{87}Sr/^{86}Sr$비와 AMS를 이용하여 측정한 $^{14}C$ 동위원소 년대를 토대로 동래온천수의 나이 즉 온천수-지하수-지표수-천수간의 순환속도를 토의하고자 한다. 연구결과, 2008년도의 2차례에 걸쳐 채취된 동래온천수의 $^{87}Sr/^{86}Sr$비는 0.705663-0.705688로 매우 안정된 값을 갖고 있으며, 이는 천부지하수, 지표수, 해수 및 천수보다 낮은 값이다. $^{14}C$ 동위원소 연대에 의하면, 온천수는 1271년에서 2467년 비보정연대(BP)를 보여주고, 지표수는 -495년으로 나타났다. 이는 동래온천수의 순환속도가 적어도 2500년 이상임을 지시해준다. 이와 같은 순환연대는 현재 사용되고 있는 동래온천수는 과거에 가열된 고온의 물과 현재의 천부지하수와의 혼합수임을 지시해주는 것이다.

• 대한수의학회지
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• 제28권2호
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• pp.285-297
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• 1988

The present study was conducted in order to get the normal hematologic values of Korean Jindo dogs. Blood samples were taken from 328(♂ 92, ♂ 236) healthy Jindo dogs in Jindo area. The results obtained in this study were summarized as follows: 1. The mean values of red blood cell(RBC) count, hemoglobin(Hb) content and packed cell volume(PCV) in the age group of less than one year were 6.77(♂ 6.80, ♂ 6.76)${\times}10^6/{\mu}l$, 13.14 (♂ 13.53, ♂ 12.99)g/100ml and 43.28(♂ 44.47, ♂ 42.79)ml/100ml, respectively, whereas the RBC count, Hb content and PCV in the age group of one year and more were 7.42(♂ 7.44, ♂ 7.42)${\times}10^6/{\mu}l$, 14.98(♂ 15.56, ♂ 14.76)g/100ml and 47.18 (♂ 48.43, ♂ 46.71)ml/100ml, respectively. The values of RBC count, Hb content and PCV appeared to be higher in the male than in the female and it increased with aging in the age group of less than one year. 2. The mean values of mean corpuscular volume(MCV), mean corpuscular hemoglobin(MCH) and mean corpuscular hemoglobin content(MCHC) in the age group of less than one year were 63.93(♂ 65.40, ♂ 63.30)fl, 19.41(♂ 19.90, ♂ 19.22) pg and 30.36(♂ 30.43, ♂ 30.36)g/100ml respectively, whereas the MCV, MCH and MCHC in the age group of one year and more were 63.58(♂ 65.09, ♂ 62.95)fl, 20. 19(♂ 20.91, ♂ 19.89) pg and 31.75(♂ 32.13, ♂ 31.60)g/100ml respectively. The values of MCV, MCH and MCHC appeared to be higher in the male than in the female. No differences were found in the MCV and MCH between age groups. The MCHC appeared to be higher in older age group. 3. The mean values of white blood cell(WBC) count in the age group of less than one year were 14,356(♂ 13,878, ♂ 14,551)/${\mu}l$, whereas the values of WBC count in the age group of one year and more were 13,394(♂ 12,656, ♂ 13,672)/${\mu}l$. The WBC count appeared to be higher in the female than in the male. No differences were found between age groups in the WBC count. 4. In WBC differential count the mean percentage of lymphocyte, monocyte, neutrophil and eosinophil of the age group less than one year were 33.45(♂ 31. 64, ♂ 34.18), 2.77(♂ 3.00, ♂ 2.68), 57.40(♂ 58.18, ♂ 57.08) and 6.38(♂ 7.18, ♂ 6.06)% respectively, while those of the age group one year and more were 30. 22(♂ 28.38, ♂ 30.90), 3.03(♂ 3.23, ♂ 2.95), 60.93(♂ 63.34, ♂ 60.03) and 5.82(♂ 5.04, ♂ 6.11)% respectively. Lymphocyte count appeared to be higher in the female and in the age group below one year than in the male and in the age group of one year and more, whereas the reverse was the case with neutrophil and monocyte counts. 5. Mean platelet count in the age group of less than one year was 377,391(♂ 398,778, ♂ 368,721)/${\mu}l$, whereas mean platelet count in the age group of one year and more was 354,657 (♂ 373,660, ♂ 347,512)/${\mu}l$. The platelet count appeared to be higher in the male than in the female and especially lower in the age group of three years and more($305,513/{\mu}l$) than in the other age groups.

• 대한예방한의학회지
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• 제16권3호
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• pp.37-51
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• 2012

Objectives : The objective of this study is to determine the present state of patients with breast cancer use of Korean medicine(KM) and predictive factors for the use. Through this, the present study is intended to present reasonable treatment approaches for patients with breast cancer as well as communicating correct information on KM to healthcare providers and presenting objective alternatives for patients with breast cancer management based on the subjects' experience in health benefits obtained from their use of KM. Methods : To collect data for the present study, questionnaire surveys were conducted on outpatients who visited four hospitals located in Seoul, Korea during around three weeks from May 31, 2012. Although the total number of the questionnaire sheet distributed in the form of directly asking questionnaire questions was 300, 12 incomplete questionnaire sheets were excluded. Therefore, the number of questionnaire sheets actually used in analyses was 288 and thus the collect rate was 96%. Results : Major results of this study are as follows. First, the number of subjects who responded to the questionnaire was 288 in total. Forty-six percent of the patients reported KM usage and the most commonly used ginseng and qigong/exercise. KM use was found to be associated with age, experiencing side effects of cancer treamnent. Factors that affect the use of KM were analyzed by Linear Logistic Regression and the results showed that age, experiencing side effects of cancer treatment, effectiveness of cancer treatment, and satisfaction of the treatment were factors that were related with relatively more frequent use of KM. Conclusions : Comparing the previous studies, it could be seen that patients with breast cancer were highly interested in and used KM in which conventional medicine and KM are used simultaneously. Knowledge on the integrative use of KM and conventional therapies is necessary for cancer physicians and traditional Korean medical doctors to help patients make informed choices. KM use may play a role in the positive benefits associated with process of breast center treatment. Healthcare providers should communicate correct information on the KM use that has been scientifically verified and talk with each other openly. The fact that the significant correlation between predictive factors for the use of KM was identified trough the present study is quite meaningful.