검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 118

        104.
        1997.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The BV photographic photometry was made for 1714 stars (V < 19.5m) in NGC 6752, using 83 photoelectric stars and many secondary photographic standard stars over the area of 3.3' - 11.3' from the cluster center. Their data and finding chart are presented.
        5,400원
        107.
        1992.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        反復혜重올 받는 짧은 I 보 (Beam) 의 慣-비틀림 座때(Lateral-Torsional Buckling) 에 대한 흩윌뼈한 Parametric Study 를 逢行하여 보의 座맴現象올 좀 더 깊이 考흉하고자 한다. 有限한 비틀림햇形의 뒤틀림 (Warping) 이외에 m 少한 맺톨JTft形의 뒤틀립도 고려한 幾何學적 (完全) 非綠形의 一次7ê 보를 껴¥析的 모델 로 사용하고, 또한 金!홉의 周期的뺑性(Cyclic Plasticity) 쌓:tJJ을 보다 잘 나타내기 위해 多빼 週期的뿔性 모 덴올 Consistent Return Mapping Algorithm과 결합시켜 遭用한다. :한ì.ffI때 단방에서 아래와 갇은 여러가지 Parameter Study를 끊行함으로써 反復휴重을 받는 짧은 I 보의 함 -비블립 座며의 -압的 應홈을 ι~.흉한다 : 材料의 降ik~옳度, 降ik플래토 (Yield Plateau) , 뿔形率硬化,U-:tJJ 硬化(Kinematic Hardening) , 웰留應力, 作用倚重의 f.1端中心에 대 한 {f,í ι、率, 作用倚훌의 보 톰面에 대 한 높 이, 作用혜훨의 보 김이방향의 位置, 보 뻐f 面의 置f!{, 作用倚重으로 부터 멀리 떨어진 支持端의 固定度.
        4,600원
        108.
        1992.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Lateral bracing has long been used in design practice to enhance the carrying capacity of the lateral buckling of the beam. Many factors. critically important to lateral bracing performance. do not appear in design formulas. Some of these factors are discussed in this study for the application to short 1 - beams under repeated loadings through parametric studies with an analytical model : the brace 10' cation along the length of the beam. the height of the bracing above the shear center of the beam. and the strength and stiffness of the brace. The parametric studies are carried out using a propped cantilever arrangement. and also using a geometrically (fully) nonlinear beam model for the brace as well as the beam to capture the system buckling. An idealized bracing system is configured to restrain lateral motion. but not rotation. A multiaxial cyclic plasticity model is also implemented to better represent cyclic metal plasticity in con. junction with a consistent return mapping algorithm.
        4,000원
        109.
        2013.11 서비스 종료(열람 제한)
        Due to rapid industrialization and population growth uncontrolled release of heavy metals are entered into the waters. Among these heavy metals Pb(II) is one of the major toxic metal and in recent years the production and consumption of lead is increasing worldwide. Pb(II) can be entered to aqueous streams from several industries and can enter into the humans food chain through drinking water and crop irrigation. Lead can causes severe damage to the kidney, nervous system, reproductive system, liver and brain. The permissible level for lead in drinking water is 0.05 mg/l. Thus in recent years a number of methods and materials were developed to removal Pb(II) from aqueous solutions. Among these material bio-chars obtained from plant materials have gained special attention due to their low-cost and abundant nature. In present investigation we have developed magnetic bio-char composite from pine bark. Pine trees are wide spread throughout the South Korea and the bark from pine tree has no commercial use and is available as waste. Thus we have utilized this waste inexpensive material from preparing bio-char composite. The pin bark obtained was initially made into fine powder and washed several times with water and was filtered. To this powder an appropriate amounts of nitrate salts of cobalt and iron dissolved in ethanol solution was added and stirred for 15 minutes. This solution was oven dried at 70℃ and this was further calcined at 900℃ in nitrogen atmosphere. As obtained material was washed several times with water and dried in oven over night. This was used as adsorbent for treating lead contaminated aqueous solutions. As obtained bio-char composite was used to remove Pb(II) from aqueous solutions. Various parameters influencing Pb(II) removal like initial pH, contact time and initial concentration were studied. Effect of pH on Pb(II) removal was studied in the pH range from 2-8 at Pb(II) concentration 10 mg/L using an adsorbent dose of 300 mg. At below pH 3 a lower percent removal was observed whereas above pH 4>90% removal was observed. Further effect of contact time on Pb(II) removal was studied from time range between 10-180 min. Two kinetic models pseudo-first, pseudo-second-order models were used to evaluated the kinetic data and found that the data was better fitted to the pseudo-second-order model. From the overall results it was found that as prepared magnetic bio-char composite prepared from pin bark waste was effective and economic for treating Pb(II) contaminated aqueous solutions.
        110.
        2013.08 서비스 종료(열람 제한)
        Soluble-NSF attachment protein receptor (SNARE) proteins play a role in vesicle fusion, exocytosis, and intracellular trafficking in neuronal cells as well as in fertilization and embryogenesis. We investigated the expression patterns of two SNARE proteins, SNAP-25 and synaptotagmin VII (SytVII), and their regulation by pregnant mare serum gonadotropin (PMSG) during mouse ovarian follicular development. Ovaries were obtained at 0, 12, 24, 36, and 48 h post-PMSG injection of immature mice. SNAP-25 and SytVII mRNA expression levels increased gradually in a time-dependant manner. However, protein levels revealed different patterns of expression, suggesting different translational regulation following PMSG stimulation. SNAP-25 and SytVII expression was closely associated with thickening of the granulosa cell (GC) layer and follicle morphological changes from a flattened to a cuboidal shape. To explore follicle stimulating hormone receptor (FSHR)-mediated regulation of their expression, GCs from preantral follicles were cultured to examine the effects of FSHR siRNA knockdown. FSHR siRNA abolished upregulation of the SNAREs in both PMSG and FSH-stimulated GCs. This abolished gene expression was rescued by adding dibutyryl cyclic AMP to the cultures. These results suggest that SNAP-25 and SytVII expression is regulated via the FSHR-cAMP pathway during follicular development.
        111.
        2009.03 KCI 등재 서비스 종료(열람 제한)
        "Early Valley", is an early maturing potato cultivar with high yield potential. "Early Valley" is a clonal selection resulting from the cross between 'Suncrisp' and 'A87109-10'. It has medium plant height and light green foliage. "Early Valley" has medium flowering habit and white flowers. Tubers are smooth, yellow skin, light yellow flesh, round tuber shape, medium eye depth, and medium dormancy and good keeping quality. It has stable yield under wide range of climatic conditions. "Early Valley" is resistance to late blight, but moderately susceptible to common scab and hollow heart. This cultivar is also resistant to potato rotting at harvesting during the raining season. "Early Valley" has high level of antioxidant activity (about three times higher) and vitamin C (higher by 40%) than the 'Superior'. This cultivar has high level of tuber uniformity and capable of yielding 36.56 t/ha which is 17.07% higher than the control potato cultivar 'Superior' under optimum agronomical practices.
        113.
        2003.09 서비스 종료(열람 제한)
        Bovine embryos produced by in vitro maturation, feretilization and development was examined for presevation and transfer. The fertilization medium used BO medium with 5 mM/ caffeine and 10/ heparin and adjusted to a pH of 7.2 to 7.4. The final concentration of spermatozoa was adjusted to 1 cells/ motile sperm during fertilization in vitro. At 8~10 hrs after insemination, the oocytes were transferred into CR1aa medium and cultured for 7 days. Embryos were preserved by vitrification method for transfer. When the embryos of early, blastocyst and expanded blastocyst stages were frozen-thawed, the proportions of embryos with normal morphology 83.6, 88.1 and 85.2%. (중략)
        114.
        2003.09 서비스 종료(열람 제한)
        The purpose of this is to investigate the effects of vitrification in open pulled straws (OPS) on in vitro survival of porcine embryos. Blastocysts were produced by in vitro fertilization of slaughterhouse-derived, in vitro matured oocytes with frozen-thawed boar semen, and subsequent culture on granulosa cell monolayer. After frozen-thawing, embryos were culture in NCSU-23 medium with 5 mM hypotaurine, 4 mg/ BSA and 10 ng/ for 48 hrs to survival tests. When blastocysts were frozen-thawed by OPS methods, the embryos with normal morphology were 32.1, 34.5 and 38.9 % in early blastocyst, blastocyst and expanded blastocyat stages. The rates of partial damaged embryos were significantly (P<0.05) higher in early biastocysts than expanded blastocysts. In another experiment, the embryos frozen by OPS methods were cultured for 48 hrs for survival and developmental rates in vitro. The proportions of embryos hatched were 11.8, 20.2 and 33.3% in embryos frozen-thawed at stages of early blastocyst, blastocyst and expanded embryos. On the other hand, The proportions of embryo with normal morphology after culture were 23.5, 25.0 and 33.3% in embryos frozen-thawed at stages of early blastocyst, blastocyst and expanded embryos. These finding indicate the possible broader application for OPS methods that this procedure described is relatively harmless, that it can be used for blastocysts of different developmental stages.
        115.
        2003.06 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to determine the effects of two plant populations (28 and 14 plants per m2 ) and two toppings in conventional plant population (28 plants per m2 ) on soybean (Glycine max L. cv. Pungsannamulkong) cultivated in the paddy field. The two topping time were taken at 6th to 7th and 8th to 9th trifoliolate leaf stages in the conventional plant population. Experimental design for growth data was a randomized complete block with three replications, and samples were taken at R1 (July 31), R3 (August 19), R5 (September 2) and R7 (September 23) growth stages. The branch number of soybean was relatively higher in the low plant population (14 plants per m2 ) and with the topping at the 6th to 7th leaf stage, in the conventional plant population (28 plants per m2 ), and with topping at the 8th to 9th trifoliolate leaf stage in descending order. The highest average branch length of soybean was observed in the low population and the longest branch length was observed from the soybean with topping at the 6th to 7th leaf stage. The leaf number per plant was decreased in order of in the low population, with the topping at 6th to 7th trifoliolate leaf stage, with the topping at 8th to 9th trifoliolate leaf stage, and in the conventional population. The leaf area was high in the low population and with topping at 6th to 7th trifoliolate leaf stage and was relatively low in the conventional population and with the topping at 8th to 9th trifoliolate leaf stage in soybean. The dry weight of leaves and branches was high in the low population and with the topping at 6th to 7th trifoliolate leaf stage and was relatively low in the conventional population and with topping at 8th to 9th trifoliolate leaf stage. The leaf number per plant was high in the low population and with topping at 6th to 7th trifoliolate leaf stage and was relatively low in the conventional population and with topping at 8th to 9th trifoliolate leaf stage. The grain yield per 10a was high with the topping at 6th to 7th trifoliolate leaf stage.
        6