검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 874

        501.
        2010.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This paper presents a study of the influence of cutting parameters on surface finish obtained by face milling. Cutting conditions have significantly great effect on surface quality in high-precision machining. Fundamentally, surface roughness are strongly correlated with cutting parameters such as feed rate, cutting speed and depth of cut. Optimal selection of the cutting parameters can obtain better surface roughness. Therefore, optimization of the cutting parameters in a face milling based on the parameter design of the Taguchi method is adopted in this paper to improve surface roughness. And optimal cutting parameters based on the results of the S/N ratio and ANOVA analyses to performance high-precision machining is obtained and verified by confirmation test.
        4,000원
        502.
        2010.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        For an effective management of fisheries resources, we need fisheries informations necessary for the establishment of reasonable fishing effort and TAC distribution. To study the present state of by-catch and discard of gill-net fishery in the East Sea, we carried out fishing research using trammel nets in the coastal sea of Susan-port (Yangyang), Jangho-port (Samcheok) and Hupo-port (Uljin). As a result, a total of catch of Susan was 259,172g and that of Hopo was 577,638g. Thus Catch of Susan was 1.49 times more than that of Hupo considering the number of used fishing gear. And catch of Janho was 7.4 times more than that of Susan considering the number of experiment. Two methods of by-catch analysis in this study were used, one method is standardizing of listed species catching possible in fishing license, another method is regarding catch species under 1% of total catch as by-catch. As a result of by-catch analysis of two method, by-catch rate of Susan was 6.55% and 5.87% respectively, that of Hupo was 44.70% and 5.24% and that of Jangho was 0.96% and 2.31%. Discard rate of fish in Susan, Hupo and Jangho were 1.59%, 3.42%, 2.23% respectively.
        4,300원
        503.
        2010.03 구독 인증기관 무료, 개인회원 유료
        Oocyte enucleation is essential for somatic cell nuclear transfer (SCNT) in the production of cloned animals or embryonic stem cells from adult somatic cells. Most studies of oocyte enucleation have been performed using micromanipulator-based techniques, which are technically demanding, time-consuming, and expensive. Several recent studies have used chemical-induced oocyte enucleation; however, each has been plagued by low efficiency and toxicity. In this study, I found that the co-treatment of murine oocytes with demecolcine and BMI-1026, a potent cdk1 inhibitor, resulted in a high enucleation rate (97%). This method is entirely independent of a micromanipulator and is suitable for the large-scale production of enucleated oocytes. This new method of enucleation will be useful in SCNT and in the development of handmade cloning techniques.
        4,000원
        505.
        2009.12 KCI 등재 구독 인증기관·개인회원 무료
        표고(Lentinula edodes )는 대표적인 임산버섯으로서 국내 연간버섯 생산량 중 수위를 차지하고 있으며 전통적으로 원 목재배를 통하여 생산되는 임가의 소득증대에 크게 기여해 왔다. 그러나 최근 원목, 인건비 등의 급격한 상승, 농촌인구 의 고령화 , 버섯가격의 하락으로 인하여 수익성이 악화고 있 어 이에 대한 대안으로서 톱밥재배가 높은 관심을 받고 있다. 90년대 초반부터 우리나라에 도입된 표고 톱밥재배는 국내 에서 아직까지 광범위하게 보급되지 못하고 있다. 더욱이 우 리나라 기후에 알맞고 우수한 특성을 가진 품종을 육성하여 국내 표고 톱밥재배 활성화에 기여하고자 산조702호를 개 발하였다. 산조702호는 산조701호(중고온성)와 FMRI26- 04(중온성)의 일핵균주간 교잡을 통하여 육성되었으며 3년 간의 재배시험을 통하여 자실체형태가 우수하고 생산량이 높아 최종선발 하였다. 산조702호는 톱밥재배용 표고 품종 으로 국내에서 재배되고 있는 지면봉지재배, 균상재배에 알 맞은 생표고 생산용 품종이다. 배지의 배양은 20-25℃에서 100일 내외가 알맞으며 발생 및 생육적온은 15-23℃이다. 톱밥배지에서 균사의 생장속도가 빨라 기존 산조701호보다 버섯발생 최성기까지 기간이 약 5개월로 1개월 빠르고, 버섯 발생이 쉽다. 자실체는 중대엽형이고 갓색깔은 황갈색이며 갓형태는 편평형이다.
        507.
        2009.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        두 가지 다른 기질의 담체를 이용하여 살조세균 Pseudomonas fluorescens HYK0210-SK09의 포집율과 microcosm에서 Stephanodiscus hantzschii의 살조능을 파악하였다. Active carbon polyvinyl alcohol (ACPA)담체가 cellulose sponge (CS)담체보다 SK09를 높게 포집하였다. 이를 이용한 microcosm에서 ACPA담체가 CS담체보다 S. hantzschii의 살조
        4,000원
        508.
        2009.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Wireless LAN systems have been widely implemented for supporting the sireless internet services especially in the hotspot areas such as hospitals, homes, conference rooms, and so on. Compared with wired LAN systems, wireless LAN systems have the advantage
        4,000원
        511.
        2009.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study focused on changes in form and spatial uses of Urban Hanok in Bukchon, Seoul. There are 10 representative cases which have been renovated through the policy of ‘Preservation & Regeneration of Bukchon' by Seoul metropolitan government and other experts. Changes in form and spatial uses of Urban Hanok in Buckon are as follows. First, changes of scale. Trough removing extension parts, facade of renovated Hanoks are ‘transformed’ into recovering their identity. Using basements or lofts, intensive application of spaces is transformation which promotes the vitality of Hanoks. Second, changes of space organization. As Hanok changes its function from residence to commercial or cultural use, it also changes space character or reorganizes space organization. It is important that deciding function of Hanok has to adjust its scale and organization. Third, changes of construction performance. Through introducing new material and constructing method, performance of wall has been changed respecting its wooden structure and interior-exterior figure. However, technical studies must back it up not to destroy its value of eco-friendly architecture. Fourth, changes of facility systems, like floor heating system. They changes floor level of Hanok equally, and then sections of Hanok have became simple. Furthermore, inserting new facility space, such as boiler room, stand-up kitchen, bathroom and toilet, organization of space also changed. It is necessary that wise alternative proposal through the method of transformation or mutation must be presented. These four changes can be classification into method of ‘transformation’ and ‘mutation’. Changes of scale are method of transformation and changes of space organization are method of mutation. Also, while changes of construction performance are mutation, changes of facility systems are transformation. Recently, as price of lots have been increased, a lot of Hanoks have been commercialized, The commercial energy threat ‘the identity of Bukchon as residential area’. From now on, to operate ‘identity’ and ‘vitality’ complementary, it is necessary to make up for the preservation policy of Hanok and consolidate renovating standards of Hanok which correspond to characterof particular region and building usage.
        5,100원
        513.
        2008.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        SnO nanosheets were prepared at room temperature through a reaction between an aqueous solution of SnCl2, N2F4, and NaOH and were converted into SnO2 nanosheets without a morphological change. The SnO nanosheets were formed through a dissolution-recrystallization mechanism. Uniform and well-dispersed SnO nanosheets with the round-shape morphology were attained when the solution was treated by ultrasonic sound immediately after the addition of NaOH. The SnO2 nanosheets prepared by means of solution reduction under the ultrasonic treatment, and subsequent oxidation at 600˚C showed a high level of gas sensitivity to C2H5OH and CH3COCH3.
        4,000원
        515.
        2007.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        통영 바다목장 해역에서 식물플랑크톤 군집에 미치는 물리 화학적 환경요인을 파악하기 위하여 2000년 4월부터 2007년 1월까지 10개 정점의 표.저층에서 계절별 조사를 원칙으로 총 24회 조사하였다. 수온은 각 계절별 차이가 뚜렷한 전형적인 온대성 기후의 영향을 받고 있었으며, 염분은 쿠로시오 난류의 영향에 따른 고염분과 여름철 장마와 폭우에 따라 낮은 염분농도를 보였다. 부유물질은 표층보다 저층이 높은 농도를 보였으며, 투명도는 계절별로 여름철에 6
        4,000원
        516.
        2007.06 구독 인증기관 무료, 개인회원 유료
        Previous studies have shown that BMI-1026 is a potent inhibitor of the cyclin-dependent kinases (cdk). In cell culture, the compound also arrests G2/M strongly and G1/S and S weakly. Two key kinases, cdk1 (p34cdc2 kinase) and mitogen-activated protein (MAP) kinase (erk1 and 2), perform crucial roles during oocyte maturation and, later, metaphase II (MII) arrest. In mammalian oocytes, both kinases are activated gradually around the time of germinal vesicle breakdown (GVBD) and maintain high activity in eggs arrested at metaphase II. In this study, we examined the effects of BMI-1026 on GVBD and MII arrest in mouse oocytes. BMI-1026 inhibited GVBD of immature oocytes and activated MII-arrested oocytes in a concentration-dependent manner, with more than 90% of oocytes exhibiting GVBD inhibition and MII activation at 100 nM. This is approximately 500~1,000 times more potent than the activity reported for the cdk inhibitors roscovitine (~50 M) and butyrolactone (~100 M). Based on the results of previous in vitro kinase assays, we expected BMI-1026 to inhibit only cdk1 activation in oocytes and eggs, not MAP kinase. However, in our cell-based system, it inhibited the activity of both kinases. We also found that the effect of BMI-1026 is reversible. Our results suggest that BMI-1026 inhibits GVBD and activates MII-arrested oocytes efficiently and reversibly and that it also inhibits both cdk1/histone H1 kinase and MAP kinase in mouse oocytes.
        4,000원
        518.
        2007.04 KCI 등재 구독 인증기관·개인회원 무료
        Heat shock p1'otein (Hsp) 40 acts as a co-cha perone of Hsp70 by fac ilitating the ATPase activity of Hsp70 as well as promoting the protein fo lding and rena turation by Hsp70. In the present study. Hsp40 gene was fu sed with a gene f’ragment encoding the HJV-l TAT protein transduction domain(YGRKKRRQRRR) in a bacterial exp1' ession vector pTAT-HA to produce the TAT-fused Hsp40(TAT- Hsp40). Purified TAT-Hsp40 was effectively t 1'ansduced into the HEK 293 cells in a time- and dose-dependent manne1' To examine the effec t of TAT- Hsp40 upon oxidalive stress, HEK293 cells were exposed to H2Û2. Oxidative stress induced the ra pid increase of proteasome activity foll owed by celJ death in HEK 293 cells However ‘ HEK 293 cells t 1'ansduced by TAT- Hsp40 showed r esistance against oxidative st 1'ess induced cytot oxicity, TAT- Hsp40 transduced cell s showed dec1'eased p1'oteasome activity and inhibi ted Hs p70 degradation. These results suggest that Hs p40 rnight protect cell death f rom oxida tive st1'ess by p1'ese1'ving the cellula1' level of Hs p70.