• Title/Summary/Keyword: present-age

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The present status and future perspective of the latest communication transmission technology (최신의 통신전송기술의 현황과 전망-( I ))

  • 조규심
    • Journal of the Korean Professional Engineers Association
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    • v.24 no.1
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    • pp.95-103
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    • 1991
  • The communication transmission engineering plays the most important role in electrical communications engineering. Recently, it has been making remarkable progress as an infrastructure supporting informationaged society. Specially, the start of television conference and service of high speed digital transmission can be said it is announcing a raising curtain of high speed broad band age. Together with high speed broad band service needs a capacity as much as several or several hundred times of telephone with one circuit, various kinds of service forms are anticipated to emerge, it is anticipated to give a big impact to the way of future communications newtork. At present, telecommunication network is transforming telephone voice information by analog technology into a flexible higher system disposable of a variety of information such as pictures or data other than telephone by the introduction of digital technology. Consequently, the development of hereafter for the following respective technologies is desired.

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The present status and future perspective of the latest communication transmission technology (최신의 통신전송기술의 현황과 전망-(II))

  • 조규심
    • Journal of the Korean Professional Engineers Association
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    • v.24 no.2
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    • pp.127-136
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    • 1991
  • The communication transmission engineering plays the most important role in electrical communications engineering. Recently, it has been making remarkable progress as an infrastructure supporting informationaged society. Specially, the start of television conference and service of high speed digital transmission can be said it is announcing a raising curtain of high speed broad band age. Together with high speed broad band service needs a capacity as much as several or several hundred times of telephone with one circuit, various kinds of service forms are anticipated to emerge, it is anticipated to give a big impact to the way of future communications network. At present, telecommunication network is transforming telephone voice information by analog technology into a flexible higher system disposable of a variety of information such as pictures or data other than telephone by the introduction of digital technology. Consequently, the development of the hereafter for the following respective technologies is desired.

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Clinical evaluation of atrial septal defect (심방중격결손증의 외과적 고찰)

  • Kim, Hyeon-Sun;Seo, Gyeong-Pil
    • Journal of Chest Surgery
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    • v.16 no.4
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    • pp.511-517
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    • 1983
  • For the purpose of clinical analysis of secundum atrial septal defect, the patients with atrial septal defect operated on during the period from Aug. 1959 to Aug. 1983 were analysed. The age of the patients was ranged from 3 months to 60 years and there were 132 males [45.3%] patients and 145 female patients [54.6%] in this series. The most frequent type was oval type defect in 219 [86.9%]. The PAPVC were present in 7 patients of high defect group. Clinical analysis revealed 53 patients [19.9%] were asymptomatic. The QP/QS above than 3.61 were 45 patients and less than 1.5 were 24 patients. The pulmonary artery pressure was 10 to 100 mmHg. The majority of the defects were closed in primary suture and closed with a Dacron patch in 19 patients. The postoperative complications occurred in 35 patients [13.1%] and the most frequent complication was wound problem which was present in 10 patients. The hospital mortality rate was 1.6%.

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A Study on The Compressive Strength Correlation by Various Nondestructive Test Method (각종 비파괴 검사법에 의한 압축강도 상관연구)

  • 최원호;신도철;이대우
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10b
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    • pp.767-772
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    • 1998
  • schumidt hammer and ultra-sonic method are commonly used for concrete compressive strength test in a construction field. At present, various kinds of equations for estimation of strength are present, which have been used in a construction field. The purpose of this study is to evaluate the correlation between estimation strength by presentation equations and destructive strength to test specimen, and find out which is a suitable equation for this construction site. In this study, a strength test was carried out destructive test by means of core sampling. Non destructive test was conducted Schumidt hammer and ultra-sonic method, the experimental parameter were concrete age, test method and strength level. It is demonstrated that the correlation behavior of concrete strength in this study good due to the performs analysis of correlation between core strength and nondestructive strength.

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Prenatal Development of Gonadotropin Releasing Hormone (GnRH) Neurons in the Rat Brain (흰쥐 태아 뇌에서 GnRH 신경세포의 초기발생과정)

  • 이영기;최완성
    • The Korean Journal of Zoology
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    • v.34 no.4
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    • pp.491-499
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    • 1991
  • The present experiment was carried out 1) to study the developmental topography of GnRH neuronal system and 2) to characterize the cellular localization of GnRH neurons in the prenatal brain development of the rat. At embryonic day (I) 14.5, immunoreactive cell bodies of GnRH were first seen in the nasal septum and in the ganglion terminate located in the ventral protion of the caudal olfactory bulb. Two days later (E 16.5), GnRH-containing neurons were observed at the level of olfactory tubercle and diagonal band of Broca, which is the first appearance in the intracerebral region. From 118.5, the topographic pattern of immunoreactive GnRH perikarya was similar to that of adult rats. The present data suggest that GnRH neurons were originated from the nasal septum and gradually extended to the hvpothalamic regions with increasing fetal age.

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Generation of Miniaturized Ovaries by In Vitro Culture from Mouse Gonads

  • Jang, Si Won;Choi, Hyun Woo
    • Development and Reproduction
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    • v.25 no.3
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    • pp.173-183
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    • 2021
  • The incidence of infertility among individuals of reproductive age has been growing due to genetic and environmental factors, and considerable research efforts are focused on solving this issue. Ovarian development is an overly complex process in the body, involving the interaction between primordial germ cells and gonad somatic cells. However, follicles located in the center of the in vitro ovary are poorly formed owing to ovarian complexity, nutrient deficiency, and signaling deficiency. In the present study, we optimized methods for dissociating gonads and culture conditions for the in vitro generation of miniaturized ovaries. The gonads from embryos were dissociated into cell masses and cultured on a Transwell-COL membrane for 3-5 weeks. Approximately 12 follicles were present per in vitro ovary. We observed that miniaturized ovaries successfully matured to MII oocytes in vitro from 150 to 100 ㎛ gonad masses. This method will be useful for investigating follicle development and oocyte production.

Testicular Cell Indices and Peripheral Blood Testosterone Concentrations in Relation to Age and Semen Quality in Crossbred (Holstein Friesian×Tharparkar) Bulls

  • Rajak, S.K.;Kumaresan, A.;Gaurav, M.K.;Layek, S.S.;Mohanty, T.K.;Aslam, M.K. Muhammad;Tripathi, U.K.;Prasad, Shiv;De, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.11
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    • pp.1554-1561
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    • 2014
  • Present study analyzed the changes in peripheral blood testosterone concentrations and testicular cytogram in relation to age and semen quality in crossbred males. Three different age groups of crossbred males viz. bull calves (6 months, n = 5), young bulls (15 months, n = 5) and adult bulls (4 to 6 years, n = 8) were utilized for the study. Testicular fine needle aspiration cytology technique was used to quantify testicular cytology and their indices. Peripheral blood testosterone concentrations were measured using enzyme-linked immunosorbent assay method. Semen samples collected from adult bulls were microscopically evaluated for quality parameters. Mean peripheral blood testosterone concentrations in bull calves, young bulls and adult bulls were $2.28{\pm}0.09ng/mL$, $1.42{\pm}0.22ng/mL$ and $5.66{\pm}1.08ng/mL$ respectively, and that in adult bulls were significantly different (p<0.01) from young bulls and bull calves. There was no significant difference between the proportion of different testicular cells in bull calves and young bulls. Between young and adult bulls, significant differences (p<0.01) were observed in the proportion of spermatocytes, spermatozoa, and sperm: Sertoli cell ratio. The proportions of Sertoli cells showed a significant difference (p<0.01) between the three age groups. The number of primary spermatocytes had a positive correlation with peripheral blood testosterone concentrations in bull calves (r = 0.719, p<0.01). Number of Sertoli cells per 100 germ cells was negatively correlated with blood testosterone concentration in young bulls (r = -0.713, p<0.01). Among different semen parameters in adult bulls, ejaculate volume (r = 0.790, p<0.05) had positive relationship, and sperm motility had significant negative correlation (r = -0.711, p<0.05) with testosterone concentrations. The number of Sertoli cells and Sertoli cell index had a positive correlation with various semen quality parameters (p<0.001). Results of the present study conclude that number of Sertoli cells and Sertoli cell index are good indicators of semen quality, but peripheral blood testosterone concentrations may not have a direct relationship with various seminal attributes in crossbred bulls.

Repair of Aortic Coarctation and Arch Hypoplasia in Infants and Children (영아 및 소아에서의 대동맥궁의 형성부전을 포함한 대동맥 교약증의 수술요법 -21년간의 수술 경험-)

  • Sin, Yun-Cheol;Lee, Jeong-Ryeol;Kim, Yong-Jin;No, Jun-Ryang
    • Journal of Chest Surgery
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    • v.29 no.3
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    • pp.285-291
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    • 1996
  • We have reviewed 157 cases of coarctation of aorta in the age of infancy and children from March 1973 to december 1994. Patients were 9) males and 64 females, and their age ranged from one month to fifteen years (23.8 $\pm$ 41.6months) with 113 infant cases. In the infantile age, congestive heart failure was the most common chief complaint (781113), and above that age, asymptom was most common (15/44). Isolated coarctation was present in 31 patients, and 9 patients had additional atrial septal defect (group I), 73 patients had associated ventricular septal defect (group II), and 44 patients had associated complex intracardiac lesions(group III). Aortic arch hypoplasia was present in 17 patients. , The operations perf'ormed were subclavian flap angioplasty in 71 patients, resection and anastomosis in 32 patients, patch aortoplasty in 26 patients, resd extended end-!o-end anastomosis in 27 patients, and direct angioplasty with resection of web in 1 patient. The early mortality was 17.2% (27/157) and re-coarctation rate was 18.0% (281157). The most common complication was respiratory problem in infants and postoperative hypertension in children.

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Bite Force and Lip Closing Force Measurement in Preschool Children (학령 전 어린이의 교합력과 구순 폐쇄력)

  • Cho, Nayoung;Kim, Hyeongun;Kim, Jaegon;Baik, Byeongju;Yang, Yeonmi
    • Journal of the korean academy of Pediatric Dentistry
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    • v.42 no.3
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    • pp.233-241
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    • 2015
  • The aim of this study was to determine the bite force and lip closing force in preschool children and to analyze the correlation between these forces by age, height and weight, respectively. Data were obtained from 98 children (56 males, 42 females) ranging from 3 to 6 years of age. The magnitude of the bite force was measured bilaterally corresponding with the 2nd primary molars using a bite force gauge, $GM10^{(R)}$ (Nagano Keiki) and the force of lip closure was measured using LIP DE $CUM^{(R)}$ (Cosmo Instruments). The averages of bite force for boys and girls were 217.69 N and 205.05 N, respectively. The relationship between bite force with age, height, and weight present significant positive correlation (p < 0.001, p < 0.001, and p < 0.001, respectively). The averages of lip closing force for boys and girls were 4.81 N and 4.07 N respectively. The relationship between lip closing force with age, height, and weight present significant positive correlation (p < 0.001, p < 0.001, and p < 0.001, respectively). No significant differences were observed between boys and girls (p > 0.05) in both forces. A significant correlation was observed between lip closing force and bite force (p = 0.002).

Comparative Study on Maternal Health Status With Island and Land Women in A Middle City Area (중도시내(中都市內) 도서(島嶼)와 육지거주부인(陸地居住婦人)의 모성보건실태비교(母性保健實態比較))

  • Kim, Kyu-Chul
    • Journal of Preventive Medicine and Public Health
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    • v.9 no.1
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    • pp.65-75
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    • 1976
  • To compare the maternal health status between women in island and land, the study was conducted to adjacent land (kukdong) and island (kyonghodong) areas in Yosoo city during April 1976. The results obtained from 174 interviewee in island and 192 in land areas were the same as follow, 1. General characteristics of both area. Age: Land, group 20-29 year of age was the largest. Island, 30-39 year of age was the largest. Education; Low educated group, less than primary grade (land 88.6%, island 93.1%), was predominant in both area. Occupation of herself; agriculture and labor was the main occupation (land 50%, island 82.2%) in both area. Occupation of husband: labor and fishery was general (81.2%) in land, and agriculture and fishery was general (81.6%) in island. Duration of residence; Land, 25.0% being resided here more than 10 years. Island, 64.3% being resided here more than 10 years. 2. Marriage, Pregnancy, and Present children. Average age at marriage; Land, 20.7 years. Island, 20.9 years. Average frequency of pregnancy; Land, 4.4 times. Island, 4.3 times. Wastage of pregnancies: Land, 236 per 1000 pregnancies. Island, 151 per 1000 pregnancies. Wastage occupied by induced abortion; land, 73.5%. island, 60.5%. Number and sex of present children; Land, 3.3 per family, sex ratio 52.4 to 47.6. Island, 3.6 per family, sex ratio 53.3 to 46.7. 3. Prenatal and postnatal care. Prenatal consutation: Land, 16.1% received by doctor or midwife. Island 9.2% received by doctor or midwife. Complications during last pregnancy; Land, 46.6% complained. Island, 51.1% complained. Return to work within 1 week after delivery; Land, 40.6%. Island, 50.6%. 4. Delivery environment Home delivery; Land, 97.4% Island, 97.3%. Delivery attdended by non medical professions at home; Land, 80.2% Island, 93.7%. Solo home delivery; Land, 13.0%, Island, 12.9%. Delivery attended by layman without taking any disinfective preparations; Land, 48.1%, Island, 49.1%. Material mainly used to cut umbilical cord at home; Land, scissors (97.4%). Island, scissora (98.8%). Cord cutting material used without giving any disinfective preparations; Land, 79.9%, Island, 84.0%. Delivery sheets used at home; Cement bag paper (land 50.0%, island, 31.3%). Vinyl sheets (land,17.5%, island, 27.6%). News paper (land, 3.2%. island, 11.7%). No sheets (land 19.5%. island, 12.9%). etc. Maternal Meal; Seaweed soup with rice was the most general in both area. (land 95.3%, island, 91.4%).

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