RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
          펼치기
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재

        강건 실험계획법을 이용한 열화자료의 분석

        서순근,하천수 한국품질경영학회 2004 품질경영학회지 Vol.32 No.1

        The reliability of the product can be improved by making the product less sensitive to noises. Especially, it is important to make products robust against various noise factors encountered in production and field environments. In this paper, the phenomenon of degradation assumes a simple random coefficient degradation model to present analysis procedures of degradation data for robust experimental design. To alleviate weak points of previous studies, such as Taguchi's, Wasserman's, and pseudo failure time methods, novel techniques for analysis of degradation data using the cross array that regards amount of degradation as a dynamic characteristic for time are proposed. Analysis approach for degradation data using robust experimental design are classified by assumptions on parametric or nonparametric degradation rate(or slope). Also, a simulation study demonstrates the superiority of proposed methods over some previous works.

      • KCI등재

        불확정 모형하에서 가속수명시험의 최적 설계

        서순근,하천수,김갑석 한국품질경영학회 2001 품질경영학회지 Vol.29 No.3

        This paper presents new compromise ALT plan which is applied to situations that true relationship between stress and parameters is not known exactly. The assumed failure distribution of this study is one of location-scale family, i. e., exponential, Weibull, and lognormal distributions which have been ones of the popular choices of failure distributions. The method of applying the stress is constant, and the censoring mechanism is Type I censoring. Compared with existing compromise plans under true simple linear model in terms of statistical efficiency, the efficiency of new compromise plan is better than the corresponding other compromise ones in most cases. For case when true model is quadratic, this plan can be used without any severe loss in statistical efficiency. The proposed new compromise ALT plan is illustrated with a numerical example and sensitivity analyses are conducted to study effects of pre-estimates of design parameters.

      • KCI등재

        Dynamic characteristics of a planetary gear system based on contact status of the tooth surface

        Ruibo Chen,Jianxing Zhou,Wenlei Sun 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.1

        Studies on the planetary gear have attracted considerable attention because of its advantages, such as compactness, large torque-toweight ratio, vibrations, and high efficiency, which have resulted in its wide applications in industry, wind turbine, national defense, and aerospace fields. We have established a novel dynamic model of the planetary gear transmission by using Newton’s theory, in which some key factors such as time-variant meshing stiffness, phase relationships, and tooth contact characteristics are considered. The influences of gear axial tipping, operating conditions, and the meshing phase on the contact characteristics and the dynamic characteristics were researched systematically. It was found that the contact area of the tooth surface was moved due to the axial gear tipping, which obviously affected the meshing stiffness. With the increase in the inclination angle of the sun gear, the meshing stiffness decreases, which produces an evident influence on the high natural frequency in the planetary transmission system. In terms of the dynamic characteristics of the system, the component of rotating frequency appeared in the dynamic meshing force of the sun gear and the planetary gear. Moreover, the floating track of the center wheel varied significantly and exhibited an oval distribution as the inclination angle of the sun gear changed. When the inclination angle of the sun gear increased, the rotating frequency component increased significantly, but the other meshing frequency components remained unchanged; meanwhile, the deformation of the floating track also increased. If the inclination angle of the sun gear changes, the vibration state of the system and the collision impact could become more serious, and the lifetime of the planetary transmission system will reduce. Furthermore, when the load was increased, we found that the gear-tooth contact zone transformed from line contact to surface contact, the meshing stiffness increased, the effect of high natural frequency on the planetary transmission system became more evident, but its low-order natural frequency remained stable. With regard to the dynamic characteristics of the system, the components of the major frequency at the external gearing remained unchanged, but the rotation frequency of the sun gear and the meshing frequency amplitude increased linearly with the increase in load. In conclusion, the variation in the meshing stiffness of the planetary gear system had minor impact on the low-order natural frequency, but had a significant impact on the high natural frequency of the planetary transmission system due to the phase variation of the gear.

      • SCIESCOPUSKCI등재

        Effects of maternal dietary energy restriction on laying performance, embryonic development, and lipid metabolism in broilers

        Sun, Hao,Chen, Zhihui,Ma, Chengzhan,Lian, Lina,Zhao, Zeyu,Niu, Shupeng,Xu, Liangmei,Sun, Jinhua Asian Australasian Association of Animal Productio 2022 Animal Bioscience Vol.35 No.5

        Objective: The objective of this study was to investigate the effects of different degrees of maternal dietary energy restriction on lipid deposition in embryonic tissues during the medium laying period (37 to 39 weeks) in Arbor Acres (AA) broiler breeders. Methods: A single factor design was adopted, and 400 AA broiler breeders (20 weeks of age) with a similar weight were randomly allocated into four groups. The birds in the control group were fed a corn-soybean meal based diet, and those in trial groups were fed diets with 80%, 70%, and 50% energy levels of the basal diet. Incubated eggs from the medium laying period were collected. Samples of developing embryos at various stages were prepared for composition analysis. Results: The embryo weight in the 80% energy group was higher than those of the other groups on embryonic day (E) 13, but at 21 E, they were significantly decreased with decreasing energy intake of the broiler breeders (p<0.05). Additionally, the levels of crude fat in tissues in the restriction groups were significantly decreased (p<0.05). The long axis and area of adipocytes in breast muscle, thigh muscle and the liver were significantly decreased (p<0.05) at 21 E in the 80%, 70%, and 50% energy groups. Conclusion: The effects of the 80% maternal dietary energy restriction energy affects egg production performance, egg quality, and nutrient deposition in egg weights, which then directly impacts on the developmental process of embryos, especially on fat utilization and deposition.

      • SCIESCOPUSKCI등재

        Proteomic analysis of amino acid metabolism differences between wild and cultivated Panax ginseng

        Sun, Hang,Liu, Fangbing,Sun, Liwei,Liu, Jianzeng,Wang, Manying,Chen, Xuenan,Xu, Xiaohao,Ma, Rui,Feng, Kai,Jiang, Rui The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.2

        Background: The present study aimed to compare the relative abundance of proteins and amino acid metabolites to explore the mechanisms underlying the difference between wild and cultivated ginseng (Panax ginseng Meyer) at the amino acid level. Methods: Two-dimensional polyacrylamide gel electrophoresis and isobaric tags for relative and absolute quantitation were used to identify the differential abundance of proteins between wild and cultivated ginseng. Total amino acids in wild and cultivated ginseng were compared using an automated amino acid analyzer. The activities of amino acid metabolism-related enzymes and the contents of intermediate metabolites between wild and cultivated ginseng were measured using enzyme-linked immunosorbent assay and spectrophotometric methods. Results: Our results showed that the contents of 14 types of amino acids were higher in wild ginseng compared with cultivated ginseng. The amino acid metabolism-related enzymes and their derivatives, such as glutamate decarboxylase and S-adenosylmethionine, all had high levels of accumulation in wild ginseng. The accumulation of sulfur amino acid synthesis-related proteins, such as methionine synthase, was also higher in wild ginseng. In addition, glycolysis and tricarboxylic acid cycle-related enzymes as well as their intermediates had high levels of accumulation in wild ginseng. Conclusion: This study elucidates the differences in amino acids between wild and cultivated ginseng. These results will provide a reference for further studies on the medicinal functions of wild ginseng.

      • KCI등재

        Smad4 mediates malignant behaviors of human ovarian carcinoma cell through the effect on expressions of E-cadherin, plasminogen activator inhibitor-1 and VEGF

        ( Chen Chen ),( Ming Zhong Sun ),( Shu Qing Liu ),( Dong Mei Yeh ),( Li Jun Yu ),( Yang Song ),( Lin Lin Gong ),( Li Hong Hao ),( Jun Hu ),( Shu Juan Shao ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2010 BMB Reports Vol.43 No.8

        Smad4 is involved in cancer progression and metastasis. Using a pair of human syngeneic epithelial ovarian cancer cells with low (HO-8910) and high (HO-8910PM) metastatic abilities, we aimed to reveal the role of Smad4 in ovarian cancer metastasis in vitro. Smad4 was down-regulated in HO-8910PM cell line relative to HO-8910 by implicating Smad4 was probably a potential tumor suppressor gene for ovarian cancer. Re-expression of Smad4 decreased the migration ability and inhibited the invasion capacity of HO-8910PM, while promoted the cell adhesion capacity for HO-8910PM. The stable expression of Smad4 increased the expression of E-cadherin, reduced the expression of plasminogen activator inhibitor-1 (PAI-1) and slightly down-regulated the expression of VEGF. Smad4 suppresses human ovarian cancer cell metastasis potential through its effect on the expressions of PAI-1, E-cadherin and VEGF. Results from current work implicate Smad4 might suppress the invasion and metastasis of human ovarian tumor cells through a TGF-β/Smad-mediated pathway. [BMB reports 2010; 43(8): 554-560]

      • SCIESCOPUSKCI등재

        Effects of processing method on the pharmacokinetics and tissue distribution of orally administered ginseng

        Chen, Jianbo,Li, Meijia,Chen, Lixue,Wang, Yufang,Li, Shanshan,Zhang, Yuwei,Zhang, Lei,Song, Mingjie,Liu, Chang,Hua, Mei,Sun, Yinshi The Korean Society of Ginseng 2018 Journal of Ginseng Research Vol.42 No.1

        Background: The use of different methods for the processing of ginseng can result in alterations in its medicinal properties and efficacy. White ginseng (WG), frozen ginseng (FG), and red ginseng (RG) are produced using different methods. WG, FG, and RG possess different pharmacological properties. Methods: WG, FG, and RG extracts and pure ginsenosides were administered to rats to study the pharmacokinetics and tissue distribution characteristics of the following ginsenosides-DRg1, Re, Rb1, and Rd. The concentrations of the ginsenosides in the plasma and tissues were determined using UPLC-MS/MS. Results: The rate and extent of absorption of Rg1, Re, Rb1, and Rd appeared to be affected by the different methods used in processing the ginseng samples. The areas under the plasma drug concentration-time curves (AUCs) of Rg1, Re, Rb1, and Rd were significantly higher than those of the pure ginsenosides. In addition, the AUCs of Rg1, Re, Rb1, and Rd were different for WG, FG, and RG. The amounts of Rg1, Re, Rd, and Rb1 were significantly (p < 0.05) higher in the tissues than those of the pure ginsenosides. The amounts of Re, Rb1, and Rd from the RG extract were significantly higher than those from the WG and FG extracts in the heart, lungs, and kidneys of the rats. Conclusion: Our results show that the use of different methods to process ginseng might affect the pharmacokinetics and oral bioavailability of ginseng as well as the tissue concentrations of Rg1, Re, Rd, and Rb1.

      • SCISCIESCOPUS

        Direct Chemical Vapor Deposition-Derived Graphene Glasses Targeting Wide Ranged Applications

        Sun, Jingyu,Chen, Yubin,Priydarshi, Manish Kr.,Chen, Zhang,Bachmatiuk, Alicja,Zou, Zhiyu,Chen, Zhaolong,Song, Xiuju,Gao, Yanfeng,Rü,mmeli, Mark H.,Zhang, Yanfeng,Liu, Zhongfan American Chemical Society 2015 NANO LETTERS Vol.15 No.9

        <P>Direct growth of graphene on traditional glasses is of great importance for various daily life applications. We report herein the catalyst-free atmospheric-pressure chemical vapor deposition approach to directly synthesizing large-area, uniform graphene films on solid glasses. The optical transparency and sheet resistance of such kinds of graphene glasses can be readily adjusted together with the experimentally tunable layer thickness of graphene. More significantly, these graphene glasses find a broad range of real applications by enabling the low-cost construction of heating devices, transparent electrodes, photocatalytic plates, and smart windows. With a practical scalability, the present work will stimulate various applications of transparent, electrically and thermally conductive graphene glasses in real-life scenarios.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2015/nalefd.2015.15.issue-9/acs.nanolett.5b01936/production/images/medium/nl-2015-019367_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl5b01936'>ACS Electronic Supporting Info</A></P>

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼