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

      오늘 본 자료

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

        Changes in Dust Activity in Spring over East Asia under a Global Warming Scenario

        Qi Zong,Rui Mao,Dao-Yi Gong,Chenglai Wu,Bing Pu,Xingya Feng,Yijie Sun 한국기상학회 2021 Asia-Pacific Journal of Atmospheric Sciences Vol.57 No.4

        Dust activity not only influences human health through dust storms but also affects climate at local and regional scales through the direct effects of dust aerosols on both solar and longwave radiative heating. In this study, based on dust simulations from seven Coupled Model Intercomparison Project Phase 5 (CMIP5) models, the spatial and temporal changes in dust activity over East Asia under a Representative Concentration Pathway 8.5 global warming scenario were examined for the periods of 2016– 2035 (P1), 2046–2065 (P2) and 2080–2099 (P3). The results show that the multimodel ensemble mean (MME) of the CMIP5 models largely captures the spatial distribution of dust emissions and dust optical depth (DOD) over East Asia during 1986–2005 (P0). The MME reproduces the increasing trend in dust emissions and DOD over dust sources in East Asia during P0. Accompanying emission reductions during P1 to P3, the DOD simultaneously decreases, and the evident DOD decline can also be found over downwind areas in eastern China and the Korean Peninsula. Simulations project increases in precipitation and the LAI (leaf area index). Simultaneously, the weakened East Asian trough leads to anomalous southerly winds and lower wind speeds at the surface. All these results indicate unfavorable conditions for dust emissions over the sources regions, resulting in a decreased DOD over East Asia during P1 to P3.

      • KCI등재
      • SCISCIESCOPUS

        <sub> L 1 </sub> finite-time stabilization for positive semi-Markovian switching systems

        Qi, Wenhai,Park, Ju H.,Zong, Guangdeng,Cheng, Jun Elsevier science 2019 Information sciences Vol.477 No.-

        <P><B>Abstract</B></P> <P>This paper investigates robust finite-time stabilization scheme for positive semi-Markovian switching systems (S-MSSs). Semi-Markovian process (SMP), external disturbances, and transient performances at a finite-time level may appear in a controlled system. A more general system model for S-MSSs that covers Markovian switching systems (MSSs) as a special case is suitable for describing some complex systems that are subject to random abrupt changes in structure and parameter. The main motivation for this is that finite-time problems can be used to describe the transient performance of practical industrial control processes. First, under the framework of stochastic semi-Markovian Lyapunov functions theory, some sufficient conditions for finite-time boundedness (FTBs) and <SUB> L 1 </SUB> FTBs criteria for positive S-MSSs are proposed for all admissible disturbances. Then, a novel <SUB> L 1 </SUB> finite-time controller design method that employs the gain matrix decomposition method is presented to reduce some conservativeness, thereby guaranteeing that the resulting closed-loop system (RLCS) could achieve positivity, FTBs, and attain a prescribed <SUB> L 1 </SUB> noise attenuation performance index in standard linear programming (LP). Finally, a practical example is introduced to show the effectiveness of the main theory</P>

      • KCI등재

        Anti-Obesity and Hypolipidemic Effects of Ethanolic Extract from Alpinia officinarum Hance (Zingiberaceae) in Rats Fed High-Fat Diet

        Dao-Zong Xia,Xin-Fen Yu,Hui-Ming Wang,Qi-Ya Ren,Bing-Mei Chen 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.4

        To investigate the anti-obesity and hypolipidemic effects of Alpinia officinarum ethanolic extract (AOE) for the first time, anti-obesity models in vivo were used. Ten male Sprague-Dawley rats were fed normal control diet (NC); other groups of rats were fed a high-fat diet (HFD) with or without different proportions of AOE (AOE-1, 3%; AOE-2, 5%) for 6 weeks to examine feed intake, body and adipose tissue weight, serum total cholesterol (Total-C), triacylglycerol (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and leptin levels, alanine aminotransferase (ALT) and aspartate aminotranferase activities, hepatic Total-C and TG levels, and the pathological changes in liver and epididymal adipose tissues. Interestingly, feed intakes among the experimental groups were not significantly different. Body weight gains were significantly lowered in the AOE-1 and AOE-2 groups compared with the HFD group (P<.05) and near to the level of the NC group. AOE also improved the lipid profile in serum and the pathological changes in liver and adipose tissue and decreased the relative weights of epididymal and perirenal white adipose tissues. They improved lipid profile by lowering serum Total-C, TG, and LDL-C concentrations, leptin content, and the atherogenic index compared with the HFD group. The HDL-C concentration and the ratio of HDL-C/Total-C significantly increased compared with those of the HFD group. The serum ALT activity of the AOE-2 group was notably lower than that of the HFD group. Our data suggest that AOE can be considered as an anti-obesity agent that is effective for suppressing body weight gain and decreasing lipid profile.

      • SCIESCOPUS
      • KCI등재

        Monazites reveal timing and genesis of Nb-REE mineralization in trachyte from the Pingli area, North Daba Mountain, China

        Xiao Nie,Zong-qi Wang,Lei Chen,Jingwu Yin,Gang Wang 한국지질과학협의회 2021 Geosciences Journal Vol.25 No.5

        In recent years, several Nb-rare-earth-element (REE) deposits have been discovered in trachyte from the Pingli–Zhenping area of the North Daba Mountain. Of these, the Zhujiayuan Nb (-REE) deposit is particularly rich in monazite. In this study, electron probe microanalysis (EPMA) and laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) were used to better understand the genesis of the deposit and constrain the timing of Nb-REE mineralization. The results show that most monazite in the deposit is closely related to various alteration minerals (biotite, sericite, albite, quartz, pyrite, and calcite), and monazite often has a lower ThO2 content (0.09–1.32 wt%), indicating its hydrothermal origin. Monazite and the dominant Nb-bearing mineral (columbite) have a close paragenetic relationship, indicating that Nb and REE were mineralized in the same period. LA-ICP-MS U-Pb dating on hydrothermal monazite grains shows a weighted average 206Pb/238U age of 237.2 ± 7.9 Ma, which represents the timing of REE mineralization. The origin of monazite, in combination with the alteration mineralogy and ore-forming age, suggests that fluid exsolved from the Early Mesozoic alkaline felsic melt induced widespread hydrothermal alteration and the formation of the Zhujiayuan Nb-REE deposit.

      • KCI등재

        A Grey Probability Measure Set based Mobile Robot Position Estimation Algorithm

        Peng Wang,Zong-Hai Chen,Qi-Bin Zhang 제어·로봇·시스템학회 2015 International Journal of Control, Automation, and Vol.13 No.4

        A novel algorithm for the position estimation of a mobile robot is proposed, which is based on probability statistics and grey system theory. For the proposed algorithm, the grey probability measure set is established, which is composed of a base set and the corresponding grey probability measure. The base set is used to represent the uncertain information and the grey probability measure distributes probability on the base set. Moreover, the integrating rules are formulated using the grey probability measure set and the q-satisfied rule to estimate the position of a mobile robot. In addition to providing a new way of representing the uncertain information, results of the proposed algorithm are also more reliable in the presence of error and outliers. The algorithm is applied in the position estimation of a Pioneer 3-DX robot in a corridor-office environment. Experimental results have shown that the estimation accuracy of the algorithm is as good as that of the particle filter and better than that of the extended Kalman filter.

      • KCI등재

        Research on the Tensile Mechanical Properties and Fracture Characteristics of GFRP Mortar Tubes under Impact Loads

        Hao Wang,Qi Zong,Haibo Wang 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.4

        To investigate the protective effect of glass fiber-reinforced plastic (GFRP) pipes on cement mortar, dynamic splitting tests were carried out on cement mortar and GFRP-mortar pipe specimens by using a 74 mm diameter Hopkinson pressure bar (SHPB) test device combined with a high-speed video camera device to obtain the crack expansion process and rupture and fragmentation morphology of the specimens. The results show that the tensile strength of cement mortar rings is lower and that the stress?strain curve is single-peaked. Compared with cement mortar rings, the tensile strength of GFRP-mortar ring specimens increases significantly, and the stress-strain curve is bimodal. For 0.5 MPa air pressure and wall thicknesses of 0, 2, 3, and 4 mm, the hollow rate of the 0.187 specimen peak stress is 3.21, 1.02, 1.05, and 1.26 times that of the 0.292 specimen. For 0.5 MPa air pressure and a hollow rate of 0.187, the wall thickness of the 2, 3, and 4 mm specimen peak stress is 1.06, 1.31, and 1.69 times that of the 0 mm specimen. The increase in the wall thickness, the decrease in the hollow rate and the increase in the strain rate make the dynamic tensile strength of the specimens increase. The dynamic modulus of elasticity of the GFRP-mortar pipe specimens was lower than that of the mortar specimens, and the increase in strain rate and the thickness of the GFRP pipe wall resulted in an increase in the dynamic modulus of elasticity of the specimens. The cement mortar specimen under impact load was split and tensile damage occurred; the GFRP-mortar specimen suffered tensile damage at the two ends of the applied force, and the upper and lower ends were crushed. With the increase in the strain rate, the GFRP-mortar specimens transitioned from cracks to the formation of “V” area damage, and the specimen crushing degree increased, but the existence of GFRP pipe can have a protective effect on the mortar, reducing the degree of specimen rupture and crushing. The increase in the hollow ratio reduces the ability of the specimen to resist the external load, and the degree of specimen rupture and fragmentation increases.

      • KCI등재

        Mineralogy and isotope geochemical characteristics for Xiaozhen copper deposit, Langao County, Shaanxi Province and their constraint on genesis of the deposit

        Gang Wang,Zong-qi Wang,Rui Shi,Ying-li Zhang,Kun-ming Wang 한국지질과학협의회 2015 Geosciences Journal Vol.19 No.2

        The Xiaozhen copper deposit is a typical deposit in the North Daba Mountain area polymetallic metallogenic belt. With the exception of geological prospecting research, however, few studies have been reported on the genesis of the deposit. This paper focuses on the mineralogical and isotope geochemical characteristics for the Xiaozhen copper deposit. Detailed field-work and microscope observations suggest that the ore’s structural fabric and mineral assemblages feature a medium–low-temperature hydrothermal pattern of metallogeny. The results of electron microprobe analysis indicate that chalcopyrite atomic ratio ΣMe/S = ~0.95–1.03, which suggests that they may not be of sedimentary origin. In addition, the S content of the pyrite is from 50.57 wt% to 53.16 wt% that is less than standard the value of 53.45 wt%, the Fe/S value is from 0.878 to 0.955, and the Ni content in pyrite is high even up to 0.38 wt%. These results, combined with Ni-Co graphic projection, indicate that the pyrite is of magmatic hydrothermal origin. Moreover, most of the sphalerites contain Se, and their calculated w(FeS) content ranging from 4.60 wt% to 10.37 wt% suggest magmatic origin and a formation temperature of approximately 300 °C. Further, the content of χ(Fe) is from 46.55 wt% to 46.97 wt% for pyrrhotites, suggesting they are clino-pyrrhotites. This result, combined with mineral assemblages and the Fe-S system diagram, indicates a mineralization temperature of approximately 310 °C. The δ34S values of the sulfide range from 2.6‰ to 11.5‰, indicating multisource properties. The 208Pb/204Pb has wider ratios (~38.897–39.918), reflecting that they contain abundant radiogenic lead. The Pb isotope tectonic setting and genetic classification plot show that the ore lead was provided mainly by the upper crust in addition to a few magma materials. The analytical results of fluid inclusions in the chalcopyrite show that the 3He/4He ratios are ~0.268–0.326 R/Ra, which is higher than the crustal ratios but grossly lower than that of the mantle fluid and that the 40Ar/36Ar ratios are higher than the argon isotopic composition of the atmosphere. Moreover, the He-Ar isotope system suggests that the source of the ore-forming fluids is predominantly meteoric low-temperature underground water, with a small amount of mantle fluid. In summary, this study has determined that the Xiaozhen copper deposit is a medium-temperature magmatic hydrothermal deposit. This finding is combined with metallogenic age to briefly describe the mineralization process.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼