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Zavkhan River and Its Catchment Area Delineation Using Satellite Image
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作者 Ochir Altansukh Munkhjargal Munkhdavaa +1 位作者 Bat-Erdene Ariunsanaa Tsetsgee Solongo 《Journal of Water Resource and Protection》 2013年第10期919-929,共11页
The purpose of this research is to define initial parameters of Khyargas Lake-Zavkhan River and its catchment area using satellite images. The study has been done by two datasets: 1) Shuttle Radar Topography Mission (... The purpose of this research is to define initial parameters of Khyargas Lake-Zavkhan River and its catchment area using satellite images. The study has been done by two datasets: 1) Shuttle Radar Topography Mission (SRTM) at a horizontal spatial resolution of 90 meters, 2) The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) at a horizontal spatial resolution of 30 meters, using two different models of ArcHydro and Integrated Land and Water Information System (ILWIS) softwares. Main methods of models, that were used in this research are the Deterministic-8, the steepest slope, the spread, the seek computations and the trace analysis. Moreover, input data of the modeling are digital elevation model (DEM) and lake position, outlet location of the river. DEM based ArcHydro model was run on the both datasets, and ILWIS model was run on SRTM data. Several intermediate results were produced while the models run, and initial parameters of the Zavkhan River, its catchment area have been defined at the end of the model. Moreover, final results of the models were compared with each other and with the result of previous research, and with the reality. The result of this study can be used in baseline and advanced research on the catchment area. Besides of that, the result can define a spatial boundary of study on Zavkhan River and its catchment area. Moreover, it would have support for decision-making on ground and surface water resource, distribution and management. Further research, which will cover the entire territory of Mongolia, has to be done using same methodology. The 332nd decision on “River catchment areas of Mongolia” of the Minister of Nature, Environment and Tourism in 2009 has to renew, if a result of that study would be accepted from vocational organization and experts. 展开更多
关键词 Khyargas Lake-Zavkhan RIVER CATCHMENT Area INITIAL Parameters of the RIVER Satellite Image mod-eling
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Mathematical Modeling of the Influence of the Wind Field Structure in the Atmosphere on the Cloud Formation Processes
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作者 Boris A. Ashabokov Lyudmila M. Fedchenko +4 位作者 Alexander V. Shapovalov Khazhbara M. Kalov Ruslan Kh. Kalov Alla A. Tashilova Vitaly A. Shapovalov 《Atmospheric and Climate Sciences》 2018年第1期84-96,共13页
The state of the physics of convective clouds and cloud seeding is discussed briefly. It is noted that at the present time there is a transition from the stage of investigation of “elementary” processes in the cloud... The state of the physics of convective clouds and cloud seeding is discussed briefly. It is noted that at the present time there is a transition from the stage of investigation of “elementary” processes in the clouds to the stage of studying the formation of macro- and microstructural characteristics of clouds as a whole, taking into account their system properties. The main directions of the development of cloud physics at the upcoming stage of its development are discussed. The paper points out that one of these areas is the determination of the structure-forming factors for the clouds and the study of their influence on their formation and evolution. It is noted that one of such factors is the interaction of clouds with their surrounding atmosphere, and the main method of studying its role in the processes of cloud formation is mathematical modeling. A three-dimensional nonstationary model of convective clouds is presented with a detailed account of the processes of thermohydrodynamics and microphysics, which is used for research. The results of modeling the influence of the wind field structure in the atmosphere on the formation and evolution of clouds are presented. It is shown that the dynamic characteristics of the atmosphere have a significant effect on the formation of macro- and microstructural characteristics of convective clouds: the more complex the structure of the wind field in the atmosphere (i.e., the more intense the interaction of the atmosphere and the cloud), the less powerful the clouds are formed. 展开更多
关键词 WIND in the ATMOSPHERE WIND Field Structure INTERACTION with CLOUDS mod-eling System Properties of CLOUDS INTERACTION of CLOUDS with the ATMOSPHERE Three-Dimensional Cloud Model
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Parameters of a severe disease course in ulcerative colitis 被引量:2
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作者 Andreas Stallmach Luisa Nickel +9 位作者 Thomas Lehmann Bernd Bokemeyer Martin Bürger Dietrich Hüppe Wolfgang Kruis Susanna Nikolaus Jan C Preiss Andreas Sturm Niels Teich Carsten Schmidt 《World Journal of Gastroenterology》 SCIE CAS 2014年第35期12574-12580,共7页
AIM:To detect high risk patients with a progressive disease course of ulcerative colitis(UC) requiring immunosuppressive therapy(IT).METHODS:A retrospective,multicenter analysis of 262 UC patients from eight German te... AIM:To detect high risk patients with a progressive disease course of ulcerative colitis(UC) requiring immunosuppressive therapy(IT).METHODS:A retrospective,multicenter analysis of 262 UC patients from eight German tertiary inflammatory bowel disease centres was performed.Patients were divided into two groups depending on the patients need to initiate immunosuppressive therapy in the disease course.A comparison between the two groups was made with regard to demographics,clinical and laboratory parameters obtained within three months after UC diagnosis and the response to first medical therapy.Using this data,a prognostic model was established to predict the individual patients probability of requiring an immunosuppressive therapy.RESULTS:In 104(39.7%) out of 262 patients,UC therapy required an immunosuppressive treatment.Patients in this group were significantly younger at time of diagnosis(HR = 0.981 ± 0.014 per year,P = 0.009),and required significantly more often a hospitalisation(HR = 2.5 ± 1.0,P < 0.001) and a systemic corticosteroid therapy at disease onset(HR = 2.4 ± 0.8,P < 0.001),respectively.Response to steroid treatment was significantly different between the two groups of patients(HR = 5.2 ± 3.9 to 50.8 ± 35.6 compared to no steroids,P = 0.016 to P < 0.001).Furthermore,in the IT group an extended disease(HR = 3.5 ± 2.4 to 6.1 ± 4.0 compared to proctitis,P = 0.007 to P = 0.001),anemia(HR = 2.2 ± 0.8,P < 0.001),thrombocytosis(HR = 1.9 ± 1.8,P = 0.009),elevated C-reactive protein(CRP)(HR = 2.1 ± 0.9,P < 0.001),and extraintestinal manifestations in the course of disease(HR = 2.6 ± 1.1,P = 0.004) were observed.Six simple clinical items were used to establish a prognostic model to predict the individual risk requiring an IT.This probability ranges from less than 2% up to 100% after 5 years.Using this,the necessity of an immunosuppressive therapy can be predicted in 60% of patients.Our model can determine the need for an immunosuppressive drug therapy or if a "watch and wait" approach is reasonable already early in the treatment course of UC.CONCLUSION:Using six simple clinical parameters,we can estimate the patients individual risk of developing a progressive disease course. 展开更多
关键词 CLINICAL practice PARAMETER Prediction mod-el Ulce
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Automatic Sleep Spindle Detection with EEG Based on Complex Demodulation Method and Decision Tree Model
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作者 Jiabin Li Bei Wang +2 位作者 Takenao Sugi Yu Zhang Masatoshi Nakamura 《Journal of Biomedical Science and Engineering》 2017年第5期10-17,共8页
Sleep spindle is the characteristic waveform of electroencephalogram (EEG) which is important for clinical diagnosis. In this study, an automatic sleep spindle detection method was developed. The EEG signals were reco... Sleep spindle is the characteristic waveform of electroencephalogram (EEG) which is important for clinical diagnosis. In this study, an automatic sleep spindle detection method was developed. The EEG signals were recorded based on the standard polysomnogram (PSG) measurement. A preprocessing procedure is introduced to exclude the unnecessary data segments and normalized the necessary data segments. Complex demodulation method is adopted to detect the candidate sleep spindle waveforms and calculate the features. The sleep spindles are recognized based on a decision tree model. Finally, the detected sleep spindles were utilized to amend the sleep stage recognition results. The sleep EEG data from 3 patients with sleep disorders were analyzed. The obtained results showed that the detected sleep spindles in EEG signal improved the accuracy of sleep stage recognition. 展开更多
关键词 SLEEP SPINDLE DETECTION COMPLEX DEMODULATION Method Decision Tree mod-el EEG
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Is Chemokine Receptor CCR9 Required for Synovitis in Rheumatoid Arthritis? Deficiency of CCR9 in a Murine Model of Antigen-Induced Arthritis
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作者 Alison Cartwright Sophie King +1 位作者 Jim Middleton Oksana Kehoe 《Open Journal of Rheumatology and Autoimmune Diseases》 2012年第4期77-84,共8页
Objectives: Monocytes/macrophages accumulate in the synovial membrane in rheumatoid arthritis and play a key role in disease pathogenesis, contributing to inflammation, cartilage destruction and bone erosion. Identifi... Objectives: Monocytes/macrophages accumulate in the synovial membrane in rheumatoid arthritis and play a key role in disease pathogenesis, contributing to inflammation, cartilage destruction and bone erosion. Identification of molecules involved in monocyte/macrophage recruitment in inflammation is crucial for development of therapeutic interventions. Chemokine receptor CCR9 is up-regulated on these cells in peripheral blood and synovium of rheumatoid patients. This study investigated the course of antigen-induced arthritis in CCR9 deficient C57BL/6 mice in comparison to wild type animals to determine whether CCR9 is critical for disease severity and progression. Methods: Methylated bovine serum albumin was used for induction of uni-lateral arthritis by direct injection into the knee joints of preimmunized animals. Arthritis is confined to the injected joint allowing comparison with the normal opposing joint. Clinical severity of arthritis was assessed by measuring swelling in the arthritic joint in comparison to the normal joint. Histological analysis was performed to assess the extent of leukocyte infiltration and cartilage depletion. Results: Levels of swelling were not significantly different between wild type and CCR9 deficient mice. Similarly there was no significant difference in histological severity of arthritis when comparing CCR9-deficient mice to wild type mice. Conclusions: CCR9 was not required for development of synovial inflammation and cartilage destruction in the anti-gen-induced model of arthritis in C57BL/6 mice in this study. This may reflect a true lack of a pathogenic role of CCR9 on monocyte/macrophage function in vivo or it may reflect differences in the current antigen-induced arthritis model when compared to human RA. 展开更多
关键词 CHEMOKINE Receptor CCR9 RHEUMATOID ARTHRITIS Inflammation Antigen-Induced ARTHRITIS Mouse mod-el Monocytes/Macrophages
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Analysis the Dynamics of SIHR Model: Covid-19 Case in Djibouti
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作者 Yahyeh Souleiman Abdoulrazack Mohamed Liban Ismail 《Applied Mathematics》 2021年第10期867-881,共15页
The Covid-19 epidemic is an emerging infectious disease of the viral zoonosis type caused by the coronavirus strain SARS-CoV-2, it is classified as a human-to-human communicable disease and is currently a pandemic wor... The Covid-19 epidemic is an emerging infectious disease of the viral zoonosis type caused by the coronavirus strain SARS-CoV-2, it is classified as a human-to-human communicable disease and is currently a pandemic worldwide. In this paper, we propose conceptual mathematical models of the epidemic dynamics of four compartments. We have collected data from the Djibouti health ministry. We study the positivity, boundedness, existence and uniqueness of the weak solution. Next, we define the Basic reproduction number by the method of the DFE and EEP. Then, we study the local and global stability and the bifurcation analysis of equilibrium to examine its epidemiological relevance. Finally, we analyze the fit of the data in comparison with the result of our mathematical results, to validate the model and estimate the important model parameters and prediction about the disease. We consider the real cases of Djibouti from 15th March to 15th May 2021. 展开更多
关键词 SIHR Model Covid-19 Basic Reproduction Number Stability Analysis mod-el Validation
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Formation and utilization of water resources of Tarim River
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作者 雷志栋 甄宝龙 +5 位作者 尚松浩 杨诗秀 丛振涛 张发旺 毛晓辉 周海鹰 《Science China(Technological Sciences)》 SCIE EI CAS 2001年第6期615-624,共10页
The Tarim River is a typical inland river in arid area without runoff yield of itself, and water resources are all supplied by its headstreams. The method of time series analysis is applied to annual runoff series of ... The Tarim River is a typical inland river in arid area without runoff yield of itself, and water resources are all supplied by its headstreams. The method of time series analysis is applied to annual runoff series of three headstreams, namely the Aksu River, Yarkant River and Hotan River to analyze their dynamic variations. A model is established to estimate water consumption in the headstream areas. Quantitative results indicate that both total annual runoff of headstreams and water consumption in the headstream areas have an increasing trend. The dynamic trends of annual runoff of hydrologic stations along the mainstream of the Tarim River are also presented to estimate the intermittence drying-up time at each station. Water consumption model of the mainstream area is used to analyze the characteristics of water consumption in the upper and middle reaches. It is shown that water consumption in each river reach of the mainstream decreases with the decrement of inflow and increases with human activities. 展开更多
关键词 Tarim River formation of water resources utilization of water resources water consumption mod-el time series analysis.
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