• Title/Summary/Keyword: early ages

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Temperature Patterns in Concrete Pavements at Very Early Ages (콘크리트 도로 포장의 초기 온도 분포 분석)

  • Kim, Seong-Min;Nam, Jeong-Hee
    • International Journal of Highway Engineering
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    • v.7 no.3 s.25
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    • pp.79-91
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    • 2005
  • The temperature patterns in Portland cement concrete (PCC) pavements were measured and comprehensively analyzed from the beginning of the concrete placement based on the temperature measurement technique developed using innovative and inexpensive temperature measurement sensors. The temperature measurements in PCC pavements were taken at several different locations forvarious slab thicknesses. The concrete temperature patterns in the vertical and longitudinal directions of the pavement were analyzed and the effects of the pavement surface reflectivity, shading, and covering on the concrete temperatures were evaluated. The results of this study showed that the significant differences in the maximum concrete temperatures on the placement day were observed according to the concrete placement time. Since the zero-stress temperature is a function of the maximum concrete temperature on the placement day, the placement time would be an important factor that affects the behavior and performance of concrete pavements. The surface conditions of the pavement, such as the surface color, shading, and covering also affected the temperature patterns in PCC pavements significantly.

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Characteristics of Compressive Strength of Concrete due to Form Curing Condition (거푸집 양생 조건에 따른 콘크리트의 압축강도 특성)

  • Kim, Kyoungnam;Park, Sangyeol;Moon, Kyoungtae;Shim, Jaeyong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.38 no.1
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    • pp.19-28
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    • 2018
  • The time for form removal is an important factor for ensuring the safety and economical efficiency of concrete structures, because it affects the quality, period, and cost of construction. Although local specifications suggest the form curing time, there is a problem of low quality of concrete due to early removing of form. This is because they do not fully understand effect of curing condition, and they want to shorten construction period in the field. Therefore, this research evaluates the effect of curing condition according to the time for form removal by testing specimen. As a result, the concrete compressive strength at the age of 28 days decreased about 40% in the condition of form removal after 12 hours, while the strength in the condition of form removal after 28 days decreased about 7%. Finally, this paper suggests an estimating equation for the concrete compressive strength due to the time for form removal considering various curing temperatures as equivalent ages. The proposed equation can be used in the field for evaluating the strength after form removal.

Petrochemical Study on the Precambrian Granitic Rocks in the Basement Area of Hambaeg Basin (함백익지(咸白益地) 기반지역(基盤地域)에 분포(分布)하는 선(先)캠브리아 화강암질암류(花崗岩質岩類)의 암석화학적(岩石化學的) 연구(硏究))

  • Yun, Hyun Sao;Lee, Dai Sung
    • Economic and Environmental Geology
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    • v.19 no.1
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    • pp.35-55
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    • 1986
  • The area of this study is located in the Sang dong district, Youngwol Gun, Kangwon Do, where the Ogcheon fold belt comes into contact with the Ryongnam massif. The area is covered by the Precambrian metasedimentary rocks of Yulri Group in the south from the line of Ungyosan-Maebongsan-Jansan-Taebaegsan Mountains and by the Cambro-Ordovician sedimentary rocks of Choseon Supergroup in the north. The Choseon Supergroup unconformably overlies the Yulri group. Several granitic intrusives occur in the Precambrian and Cambro-Ordovician terrain. The purpose of this study is to clarify the geochronology, mineralogical composition, geochemical characteristics, petrogenesis and tectonic settings of the Precambrian granitic rocks, and to evaluate the P.T. conditions of granitic intrusions. The K/Ar ages obtained from the muscovite of Nonggeori Granite, Naedeogri granite and pegmatite intruded into the Yulri Group are Early Proterozoic ($1805{\pm}18Ma$ to $1642{\pm}23Ma$), and those from the migmatitic pegmatite are Late Carboniferous ($305{\pm}4Ma$), respectively. The Precambrian granitic rocks are characterized by the presence of muscovite, tourmaline and grey feldspar with faint lineation of mafic minerals. In terms of mineralogical and chemical composition, the granitic rocks are felsic, calc-alkalic, peraluminous and S-type (ilmenite-series). The geochemical characteristics of major and trace elements indicate that the granitic rocks belong to syn-collision setting at the compressional plate margin. They were formed by progressive melting of relatively homogeneous crustal materials under 1~3kb and $670^{\circ}{\sim}720^{\circ}C$ in aqueous fluid conditions, and the Naedeogri granite was more fractionated than the Nonggeori granite. During the Taebaeg disturbance, Nonggeori granite, Naedeogri granite and pegmatite were intruded and emplaced into the Yulri Group. Migmatitic pegmatite occurring in the southwestern area, however, gave much younger muscovite age than the pegmatite intruded into the Yulri Group in rest of the area did, that might be due to the regional metamorphism of the Post-Choseon disturbance. The Geodo granitic mass and the Imog granite were intruded during the Bulgugsa disturbance.

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A Study on the Pattern Making of Men's Classic Jackets - For ages of the early in the twenties - (남성의 클래식 재킷원형에 관한 연구 -20대 초반의 남성을 중심으로-)

  • 이정임;남윤자
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.5
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    • pp.654-663
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    • 1998
  • The purpose of this study is to improve the classic jacket pattern for Korean young men whose chest circumference is 91~94cm, status is 170~175 cm, and drop value between chest and waist circumference is 15. The study was carried out by the following procedures. 1. Through the comparative investigation on the conventional classic jacket patterns of Hyung-sook Lee's, 문화's in Japan, and SMA's and the clothing experiment, the characteristics of every three patterns were found. 2. According to correct the unsuitable point in Hyung-sook Lee's pattern which was found more suitable than other two patterns and to refer to the product size of the ready-made classic jackets for men, the new suitable classic jacket pattern was achieved. 3. The sensory evaluation for appearance and comfort and one to one comparison was applied to evaluate the new classic jacket pattern by comparing with the Hyung-sook Lee' s jacket pattern. From the result of the sensory evaluation and one to one comparison, it was found that the new classic jacket pattern was more suitable for appearance and comfort. 4. From the result of this study, the suitable surplus of men's classic jacket at present is about 23~24cm on the chest circumference, 31~32 cm on the waist circumference, 14~15 cm on the hip circumference, 13~14 cm on the upper arm circumference, and 14 cm on the wrist circumference and the ease is about 3.5 cm on the armhole circumference. This size is not the absolute size but it helps to make the surplus in any other clothes for Korean young men.

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The Geometric Analysis of Fractures near the Yangsan Fault in Eonyang Area (언양지역(彦陽地域) 양산단층(梁山斷層) 부근(附近) 단열(斷裂)의 기하(幾何) 분석(分析))

  • Chang, Tae Woo;Chang, Chun Joong;Kim, Young Ki
    • Economic and Environmental Geology
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    • v.26 no.2
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    • pp.227-237
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    • 1993
  • Lineaments in the Kyungsang basin most intensely develop in the East coast domain including the Yangsan fault, which dominantly run in NNE direction. The geometry of small fault population near or along the Yangsan fault represents the dominant strikes of N35E, high angle dips and shallowly plunging rakes with dextral movement sense. Stereographic solution on the Yangsan fault geometry gives the dip of 88SE, the slip direction of 17,024 and the slip rake of 18, which were determined from the strike (N23E) of the fault measured on map, and the average attitude (N35E, 84SE) and fault striation (16, 037) of small fault population considered as Riedel shears. It is judged from the geometry of small fault population to the main Yangsan fault and dragging features of bedding attitude near the fault that the Yangsan fault was produced from dextrally strike-slip movement. The movement of the Yangsan and the adjacent parallel faults is thought to be taken place much later than the other fault sets in the Kyungsang basin. It might occur during the geologic age from Eocence to early Miocene according to the consideration of K-Ar ages of the igneous rocks near the fault. The estimated paleostress state indicates ENE shortening and NNW extension. The displacement of the Yangsan fault in the study area is not constant along the fault but decreases from the south to the north. Taking the northern end of the study area as a separating point the whole extension of the Yangsan fault may be divided into southern and northern segments.

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Fashion Market Research of Kwangju Metropolitan City - Focusing on the Distribution and Characteristics of Each Market - (광주광역시(光州廣域市) 패션상권(商圈) 조사연구(調査硏究) - 패션상권(商圈)의 분포(分布)와 특성(特性)을 중심(中心)으로 -)

  • Bae, Soo-Jeong;Choi, Mee-Sung
    • Journal of Fashion Business
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    • v.5 no.2
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    • pp.87-104
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    • 2001
  • The purpose of this study is to understand the distributions of fashion market and it's characteristics by investigating the attributes and changes of three representative fashion markets i. e. Chungjang Street Market, Underground Shopping arcades, Department Stores in Kwangju Metropolitan city. This study might contribute to the construction of more attractive fashion markets and also to consumer convenience by providing information about fashion. The method of investigation is by direct market visiting and interview from 2000. 7. 11 until 7. 30. The result is as follows; 1. Chungjang Street: This is the most famous and fashionable area, situated mainly on Chungjang street and Hwangkum-dong. The various kind of designer's boutiques, national brands, wedding shops, multi-shops etc. take place. Teenagers and people in their early twenties are the main customers. This point should be born in mind in a strategy of marketing. 2. Underground Shopping arcades: This market is open to customers of all ages and to the passengers crossing the streets and the purposeful visitors, even in rainy or snow days. However it is hard for novices to find it. 3. Department Stores: There are three department stores which are very competitive with each other by granting not only spacious and comfortable shopping areas but also places for children and cultural activities. The strategy of exhibiting unique items unparalleled in it's quality, might be needed with providing a comfortable parking lot, high quality commodes, appropriate sales program and more effective sales managements.

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A Study on the Estimation of Adhesive Stability According to Organic.lnorganic Mixed Tile Bond Type for Application of Polishing Tile to Dry Wall System (건식벽체에 폴리싱타일을 적용하기 위한 유기.무기질 혼합계 타일접착제 종류에 따른 부착안정성 평가에 관한 연구)

  • Oh, Sang-Keun;Lee, Gi-Jang;Yoo, Jae-Kang;Kim, Su-Ryun;Lee, Sung-Il
    • Journal of the Korea Institute of Building Construction
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    • v.2 no.3
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    • pp.163-170
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    • 2002
  • Recently, polishing tile(porcelain homogeneous polished tile) was used in the construction field as a finishing material. But, there happened some problems such as tile exfoliation by construction condition in early ages. Also, for use of polishing tile in the dry wall system which used to lightweight wall, the examination of adhesive stability of polishing tile is needed. In this study, adhesive strength of Polishing tile was investigated by tile bond types on gypsum board and non asbestos board coated by tar-urethane and Polymer modified cementitious waterproofing membrane(Series I). Then, the effect of heat stress and vibration was estimated on gypsum and non asbestos board(Series II). As the result of study are the follows; (1) Polishing tile(600$\times$400mm) construction on waterproofing layer : Both laboratory estimation and spot examination sieve were happened that fall of tile because their hardening speed is late. (2) To using powder style adhesives in the dry wail with waterproofing layer : Adhesive strength of tile is Influenced by interface bond area and base side condition. (3) Shock and heat stresses : obvious decline of adhesive strength is not happened

The status of anemia of high school girls in the large cities and an analysis of the related factors (대도시 여고생의 빈혈 실태와 이와 영향을 미치는 요인 분석)

  • 백준남
    • Journal of the Korean Home Economics Association
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    • v.30 no.2
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    • pp.73-80
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    • 1992
  • This study was attempted to investigate the prevalence of anemia and to obtain nutritional education data for high school girls by analyzing the factors influencing on anemia. Total fo 113 subjects(21 female high school students in Seoul and 92 female students in Inchon) were participated in this study from July 1 to July 15, 1990. Hb and Hct values were measured to evaluate the iron status. Duncan's multiple range test were performed for the comparison between the mean values of the various group. Correlations among various factors were analyzed by Pearson's correlation coefficient. The results of this study are summarized as follows. 1. The maen Hb and Hct values were 13.2g/dl and 41.3%. The rate of anemia of the subjects was 5.3% by the criteria of Hb concentration and 2.7% by the Hct value according to World Health Organization. 2. Subjects who had an early menarche had significantly higher weight and triceps than the ones ofr the girls with a late menarche. 3. There were positive relationships among Hb and Hct values, ages of memarche and cycle of menstruation. Hb, Hct values were significantly higher in the subjects who had frequent bed time snack, high intakes of meats and fishes group and vitamin A, and low calcium intake. In conculsion, the prevalence of anemia of the subjects was much lower than the previous years. There were positive relationships among Hb and Hct values, age of menarche, night snack, and intakes of meats and fishes and fruits. Therefore, it could be concluded that nutrition education should be emphasized for the high school girls to improve the quality of diet and prevent anemia.

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The study on the TH(tyrosine hydroxylase) immunoreactive cells in forebrain of developing mongolian gerbil (발달중인 Mongolian gerbil의 전뇌에서 TH 면역반응세포의 분포에 관한 연구)

  • Lee, Kyoung-youl;park, Il-kwon;Kwon, Hyo-jung;Park, Mi-sun;Song, Chi-won;Kim, Moo-kang;Chang, Kyu-tae;Lee, Kang-iee;Kim, Won-sik;Park, Won-hark
    • Korean Journal of Veterinary Research
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    • v.41 no.2
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    • pp.147-155
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    • 2001
  • The immunocytochemical localization of tyrosine hydroxylase(TH) is examined in the developmental forebrain of mongolian gerbil in order to determine changes in the distribution and cytology of neurons. At each of the different developmental stage, including prenatal(E)14, E16, E18, E20, postnatal(P)0, P2, P4 days, mongolian gerbils were sacrificed. In E14, TH-IR cells were predominantly round or oval in shape and their processes were very short. In olfactory blub, TH-IR cells were begun to appear from E20. In the striatum, we observed only fibers of TH-IR at all ages. From E16, TH-IR perikarya and fiber were present in periventricular nucleus and paraventricular nucleus of hypothalamus. The changes from the early to the late prenatal stages of development appear to be the result of an increase in number of TH-IR perikarya and processes. These results were shown slight differences to other rodents.

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Selecting QA Items & Guidelines for Hospital Safety Management (병원내 안전관리 향상을 위한 항목 및 지침 선정)

  • Park, Jee-Won;Kim, Yong-Soon;Jin, Hye-Young
    • Quality Improvement in Health Care
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    • v.3 no.1
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    • pp.78-93
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    • 1996
  • Background : The goal of this study was to establish the QA items and guidelines for preventing and improving of safety management. Therefore we investigated the nurses' recognition and knowledge of the safety and risk procedures and policies, and the agreement between the nurses beliefs on the degree of importance of those procedures and policies, with actual implementation in hospitals. Method : The subjects of this study were 201 nurses who participated in a program called continuing education for nurses, which held in December, 1993. Result: The results of this study were as follows: 1. Among 18 types of hospital risks, the items that scored highest or the need of closer attention in safety management was the needle stick, medication errors, falling, and bed sores. 2. In most questions of the 18 incidences, the nurses showed that the estimated result would have positive signs except for hospital infections, burns, and bed sores. 3. Even though the survey shows that incidences and types of occurences varies according to the person's age and the time of incident, they mostly occur between midnight to 6AM. Falls and bed sores can be seen more in the elderly. Medications errors, hospital infections and burns are frequently found between the ages of one through twenty. 4. There was a higher mean score for recognizing the importance of those items than the importance of implementing them. Conclusion : In summary, nurses did perceive the need of safety management but the hospital policy for proper safety management was not established. So we recommended that the hospital administration would undertake an early detection and proper management system for hospital precautions, based on QA items & guidelines presented in this study.

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