• 제목/요약/키워드: Change Laboratory

검색결과 2,092건 처리시간 0.033초

Climate changes impact on water resourcesinYellowRiverBasin,China

  • Zhu, Yongnan;Lin, Zhaohui;Wang, Jianhua;Zhao, Yong
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2016년도 학술발표회
    • /
    • pp.203-203
    • /
    • 2016
  • The linkage between climate change and water security, i.e., the response of water resource to the future climate change, have been of great concern to both scientific community and policy makers. In this study, the impact of future climate on water resources in Yellow River Basin in North of China has been investigated using the Coupled Land surface and Hydrology Model System (CLHMS) and IPCC AR5 projected future climate change in the basin. Firstly, the performances of 14 IPCC AR5 models in reproducing the observed precipitation and temperature in China, especially in North of China, have been evaluated, and it's suggested most climate models do show systematic bias compared with the observation, however, CNRM-CM5、HadCM5 and IPSL-CM5 model are generally the best models among those 14 models. Taking the daily projection results from the CNRM-CM5, along with the bias-correction technique, the response of water resources in Yellow river basin to the future climate change in different emission scenarios have been investigated. All the simulation results indicate a reduction in water resources. The current situation of water shortage since 1980s will keep continue, the water resources reduction varies between 28 and 23% for RCP 2.6 and 4.5 scenarios. RCP 8.5 scenario simulation shows a decrease of water resources in the early and mid 21th century, but after 2080, with the increase of rainfall, the extreme flood events tends to increase.

  • PDF

온도변화에 따른 인레이 왁스의 유동성 변화 (The flow change of the inlay waxes at various temperatures)

  • 남상용;이덕수
    • 대한치과기공학회지
    • /
    • 제28권2호
    • /
    • pp.367-373
    • /
    • 2006
  • This study was performed to observe the flow change of the inlay waxes at various temperatures. The flow of inlay waxes was tested according to the treatment conditions, for 10 minutes at 40$^{\circ}C$, 41$^{\circ}C$, 42$^{\circ}C$, 43$^{\circ}C$, 44$^{\circ}C$, and 45$^{\circ}C$ The flow of inlay waxes at various temperatures was measured with an electro dial gauge. The results were as fellows: 1. The flow change of the inlay waxes at various temperatures was shown to increase in the order of wax A, B, D, C. 2. Wax A was close to ADA specification with 3% flow at 40$^{\circ}C$ and 71% flow at 45$^{\circ}C$, but wax B and D did not reach up to ADA specification with 40% flow at 45$^{\circ}C$. 3. Wax C came up with 3% flow at 40$^{\circ}C$ and 7% flow at 45$^{\circ}C$, and it revealed a very low flow change at 5$^{\circ}C$.

  • PDF

Relationship between Tree Species Diversity and Carbon Stock Density in Moist Deciduous Forest of Western Himalayas, India

  • Shahid, Mohommad;Joshi, Shambhu Prasad
    • Journal of Forest and Environmental Science
    • /
    • 제33권1호
    • /
    • pp.39-48
    • /
    • 2017
  • With the growing global concern about climate change, relationship between carbon stock density and tree species has become important for international climate change mitigation programmes. In this study, 150 Quadrats were laid down to assess the diversity, biomass and carbon stocks in each of the forest ranges (Barkot Range, Lachchiwala Range and Thano Range) of Dehra Dun Forest Division in Doon Valley, Western Himalaya, India. Community level carbon stock density was analyzed using Two Way Indicator Species Analysis. Species Richness and Shannon Weiner index was correlated with the carbon stocks of Doon Valley. Positive and weak relationship was found between the carbon stock density and Shannon Weiner Index, and between carbon stock density and Species Richness.

Activity Change of Sphingomyelin Anabolic Enzymes during Dimethylnitrosamine-induced Hepatic Fibrosis in Rats

  • Sacket, Santosh J.;Im, Dong-Soon
    • Biomolecules & Therapeutics
    • /
    • 제16권3호
    • /
    • pp.243-248
    • /
    • 2008
  • In the present study, we investigated activity change of sphingomyelin anabolic enzymes such as sphingomyelin synthase and ceramide synthase. Sprague-Dawley male rats treated with 10 mg/kg of DMN intraperitoneally were used as a hepatic fibrosis model. Sphingomyelin synthase and ceramide synthase activities were measured in 1-week, 2-week, 3-week and 4-week DMN-treated rats along with respective control group rats. We found the increased sphingomyelin synthase activity in 4-week DMN-treated liver but not in kidney. Ceramide synthase activity was significantly increased in DMN-treated kidney after 2-week treatment and in DMN-treated liver after 3-week treatment. Although further investigation is necessary to elucidate meanings of sphingolipid metabolites during the liver fibrosis, activity change of sphingolipid anabolic enzymes may imply that sphingolipid metabolism and sphingolipid metabolites could be involved in liver fibrosis especially under oxidative stress.

하천 감조부에 있어서 질소의 장기변동에 관한 연구 (Study on the Long-term Change of nitrogen in the Tidal Area of River)

  • 김원규;강주복
    • 물과 미래
    • /
    • 제25권2호
    • /
    • pp.67-78
    • /
    • 1992
  • Several field surveys were conducted to investigate changes of water quality with time in a tidal river. Results indicated that nitrification process were dependent on the change of salinity and suspended solids concenttration. Therefore laboratory batch experiments were conducted, using suspended solids and sediment taken from a tidal river, to study the effect of salinity on nitrification and to estimate kinetic parameters of it in the tidal river. suspended solids and sediment were sampled at a point in the middle stream. Sediments were collect from the aerobic layer of mud. The change of nitrogen concentration with time was clearly explained with Monod groth model and kinetic parameters were obtained by curve fitting method. Changes in NH4-N, NO2-N, and NO3-N concentrations in the river ROKKAU with time were simulated well using Lagrangian reference frame and parameter values obtained in the laboratory tests. T도 mechanism of nitrification by suspended solids and sediment in a tidal river is shown to depend on tidal effects.

  • PDF

플라즈마 용사된 부분안정화 지르코니아 코팅의 상온 마모거동에 미치는 열처리온도 및 분위기의 영향 (The Effects of the Annealing Temperature and Environments on Room Temperature Wear Behavior of Plasma-Sprayed Partially Stabilized Zirconia Coatings)

  • 김장엽;임대순
    • 한국세라믹학회지
    • /
    • 제31권10호
    • /
    • pp.1176-1180
    • /
    • 1994
  • The sliding wear behavior of the plasma-sprayed zirconia containing 3 mol% yttria was investigated after the annealing at room temperature to 80$0^{\circ}C$ in various concentrations of humid atmosphere as laboratory, humid, dry argon atmosphere. Both of the friction coefficient and the wear loss increased with increasing temperature up to 80$0^{\circ}C$. Surface morphology of the worn samples changed with annealing temperature. The change of monoclinic/tetragonal (m/t) x-ray peak intensity ratio effected the wear behavior. The m/t ratio had maximum value at 20$0^{\circ}C$ and decreased with increased temperature in laboratory and humid atmosphere. In argon atmosphere the m/t ratio had no maximum value and decreased with increasing temperature. At all the annealing temperature humid atmosphere had more the m/t ratio value than any other atmosphere. The change of toughness was showed the inversed result of m/t ratio change. The results indicated that the resudial stress which was induced by the different amount of phase transformation takes a detrimental role in wear behavior.

  • PDF

열처리에 따른 치과도재용 합금의 표면특성에 관한 연구 (The Surface Property Change of the Heat Treated Dental Porcelain Alloy)

  • 남상용;김치영
    • 대한치과기공학회지
    • /
    • 제19권1호
    • /
    • pp.13-19
    • /
    • 1997
  • The purpose of this study was carried out by oberserving to composition of an oxide on the surface of Dental porcelain alloy according to the conditions of its heat treatment and analysing the change composition on its surface. Morphological change of the heat treated dental porcelain alloy have been investigated with SEM and EDX. The result of this study is summarized ad follows. The surface indium concentration of specimens increased as the heat treatment temperature and the oxygen partial pressure increased.

  • PDF

Global DNA Methylation of Porcine Embryos during Preimplantation Development

  • Yeo, S.E.;Kang, Y.K.;Koo, D.B.;Han, J.S.;Yu, K.;Kim, C.H.;Park, H.;Chang, W.K.;Lee, K.K.;Han, Y.M.
    • 한국가축번식학회지
    • /
    • 제27권4호
    • /
    • pp.309-315
    • /
    • 2003
  • DNA methylation at CpG sites, which is a epigenetic modification, is associated with gene expression without change of DNA sequences. During early mouse embryogenesis, dynamic changes of DNA methylation occur. In this study, DNA methylation patterns of porcine embryos produced in vivo and in vitro were examined at various developmental stages by the immunocytochemical staining method. Interestingly, active demethylation was not observed on the paternal pronucleus of porcine zygotes. However, differences were detected in the passive demethylation process between in vivo and in vitro embryos. There was no change in the DNA methylation state until the blastocyst stage of in vivo embryos, whereas partial demethylation was observed in several blastomeres from a 4 cell stage to a morula stage of in vitro embryos. The whole genome of inner cell mass (ICM) and trophectoderm (TE) cells in porcine blastocysts were evenly methylated without de novo methylation. Our findings demonstrate that genome-wide demethylation does not occur in pig embryos during preimplantation development unlike murine and bovine embryos. It indicates that the machinery regulating epigenetic reprogramming may be different between species.

Framework for False Alarm Pattern Analysis of Intrusion Detection System using Incremental Association Rule Mining

  • Chon Won Yang;Kim Eun Hee;Shin Moon Sun;Ryu Keun Ho
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
    • /
    • pp.716-718
    • /
    • 2004
  • The false alarm data in intrusion detection systems are divided into false positive and false negative. The false positive makes bad effects on the performance of intrusion detection system. And the false negative makes bad effects on the efficiency of intrusion detection system. Recently, the most of works have been studied the data mining technique for analysis of alert data. However, the false alarm data not only increase data volume but also change patterns of alert data along the time line. Therefore, we need a tool that can analyze patterns that change characteristics when we look for new patterns. In this paper, we focus on the false positives and present a framework for analysis of false alarm pattern from the alert data. In this work, we also apply incremental data mining techniques to analyze patterns of false alarms among alert data that are incremental over the time. Finally, we achieved flexibility by using dynamic support threshold, because the volume of alert data as well as included false alarms increases irregular.

  • PDF