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Evolution of Viral Load in Patients Infected with HIV-1 at Point G University Hospital
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作者 A. Maiga D. Kone +6 位作者 D. M. Coulibaly Ag M. Baraika A. Traore S. S. Diakite I. I. Maiga I. Konate A. I. Maiga 《Open Journal of Medical Microbiology》 2024年第1期66-76,共11页
Introduction: HIV, the human immunodeficiency virus, is the etiological agent of acquired immunodeficiency syndrome (AIDS). The aim of this study was to assess the evolution of the viral load in patients under treatme... Introduction: HIV, the human immunodeficiency virus, is the etiological agent of acquired immunodeficiency syndrome (AIDS). The aim of this study was to assess the evolution of the viral load in patients under treatment. Methodology: This was a study carried out from July 2017 to June 2022 at the Point G University Hospital laboratory. The determination of the viral load of patients was carried out by PCR on the ABOTT M2000sp/rt platform. Results: A total of 129 patients infected with HIV-1, aged 19 to 72 years with a mean age of 40.05 years ± 10.71;all on antiretroviral chemotherapy. The female gender predominated among our patients. The most common treatment regimen was 2INTI + 1INNTI with 72.9% followed by 2INTI + 1INI with 13.2%. As for the combinations of molecules, the combination TDF + 3TC + EFV and TDF + 3TC + DTG predominated, respectively 65.1% and 13.2%. 89.9% of our patients had undetectable viremia after 12 months of treatment (p < 0.005) with an average viral load which had evolved from 681315.65 copies/ml ± 1616908.484 to M0 at 5742.36 copies /ml ± 35756.883 at M12 (p Conclusion: Generally speaking, antiretroviral treatment had contributed to controlling viral loads, however the therapeutic combination TDF + 3TC + DTG had made it possible to obtain more patients with undetectable viremia instead. 展开更多
关键词 HIV-1 TREATMENT Viral load point G University Hospital
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Mechanical behavior of red sandstone under cyclic point loading 被引量:7
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作者 周子龙 吴志波 +2 位作者 李夕兵 李响 马春德 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2708-2717,共10页
The mechanical properties of red sandstone subjected to cyclic point loading were investigated. Tests were conducted using MTS servohydraulic landmark test system, under cyclic loadings with constant amplitudes and in... The mechanical properties of red sandstone subjected to cyclic point loading were investigated. Tests were conducted using MTS servohydraulic landmark test system, under cyclic loadings with constant amplitudes and increasing multi-level amplitudes. The frequencies range from 0.1 to 5 Hz and lower limit load ratios range from 0 to 0.60. Laboratory investigations were performed to find the effect of the frequency and the lower limit load ratio on the fatigue life and hysteresis properties of sandstone. The results show that the fatigue life of sandstone decreases first and then increases with the increase of frequency and lower limit load ratio. Under the same cycle number, the spacing between hysteresis loops increases with rising frequency and decreasing lower limit load ratio. The existence of “training” and “memory” effects in red sandstone under cyclic point loading was proved. 展开更多
关键词 red sandstone cyclic point loading fatigue life hysteresis loop PENETRATION training effect memory effect
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Analysis on the Pollution Load of Non-point Source Pollution and Surface Runoff of A Typical Village in Baiyangdian Lake Basin 被引量:5
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作者 孙添伟 陈家军 +1 位作者 史震天 王浩 《Meteorological and Environmental Research》 CAS 2010年第9期97-100,共4页
[Objective] The characteristic of non-point source pollution of a typical village in Baiyangdian Lake basin was studied.[Method] The discharge of domestic sewage and solid wastes of the typical village was investigate... [Objective] The characteristic of non-point source pollution of a typical village in Baiyangdian Lake basin was studied.[Method] The discharge of domestic sewage and solid wastes of the typical village was investigated,and both pollutant and nutrient element content were monitored,as well as the water quality and quantity of rainfall runoff.[Result] The non-point source pollution of livestock manure was far more serious than the sum of domestic sewage and domestic waste in this village,and the annual emission of total organic carbon(TOC),total nitrogen(TN) and total phosphorus(TP) was 37 794.0,4 102.9 and 1 923.7 kg,respectively.The event mean concentration(EMC)of chemical oxygen demand COD,TN and TP in rainfall runoff was 44.5,78.8,1.3 mg/L,respectively,and annual pollution load was 7.6,13.4 and 0.2 kg/hm2,respectively,while the annual pollution load of COD accounted for 5.1% of standard farmland,and that of TN and TP occupied 4.5% and 0.49% of slope farmland.[Conclusion] Livestock manure was the main source of non-point source pollution in the village and the annual pollution load of non-point source pollution was obtained. 展开更多
关键词 VILLAGE Non-point source pollution EMC Annual pollution load China
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The use of point load test for Dubai weak calcareous sandstones 被引量:4
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作者 Amr Farouk Elhakim 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第4期452-457,共6页
Intact rock is typically described according to its uniaxial compressive strength (UCS). The UCS is needed in the design of geotechnical engineering problems including stability of rock slopes and design of shallow ... Intact rock is typically described according to its uniaxial compressive strength (UCS). The UCS is needed in the design of geotechnical engineering problems including stability of rock slopes and design of shallow and deep foundations resting on and/or in rocks. Accordingly, a correct measure-ment/evaluation of the UCS is essential to a safe and economic design. Typically, the UCS is measured using the unconfined compression tests performed on cylindrical intact specimens with a minimum length to width ratio of 2. In several cases, especially for weak and very weak rocks, it is not possible to extract intact specimens with the needed minimum dimensions. Thus, alternative tests (e.g. point load test, Schmidt hammer) are used to measure rock strength. The UCS is computed based on the results of these tests through empirical correlations. The literature includes a plethora of these correlations that vary widely in estimating rock strength. Thus, it is paramount to validate these correlations to check their suitability for estimating rock strength for a specific location and geology. A review of the available correlations used to estimate the UCS from the point load test results is performed and summarized herein. Results of UCS, point load strength index and Young's modulus are gathered for calcareous sandstone specimens extracted from the Dubai area. A correlation for estimating the UCS from the point load strength index is proposed. Furthermore, the Young's modulus is correlated to the UCS. 展开更多
关键词 point load testUniaxial compressive strength (UCS)Rock characteristic elastic modulusDubai calcareous sandstoneCalcarenite
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Complete solutions for elastic fields induced by point load vector in functionally graded material model with transverse isotropy 被引量:1
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作者 Sha XIAO Zhongqi YUE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第3期411-430,共20页
The paper develops and examines the complete solutions for the elastic field induced by the point load vector in a general functionally graded material(FGM)model with transverse isotropy.The FGMs are approximated with... The paper develops and examines the complete solutions for the elastic field induced by the point load vector in a general functionally graded material(FGM)model with transverse isotropy.The FGMs are approximated with n-layered materials.Each of the n-layered materials is homogeneous and transversely isotropic.The complete solutions of the displacement and stress fields are explicitly expressed in the forms of fifteen classical Hankel transform integrals with ten kernel functions.The ten kernel functions are explicitly expressed in the forms of backward transfer matrices and have clear mathematical properties.The singular terms of the complete solutions are analytically isolated and expressed in exact closed forms in terms of elementary harmonic functions.Numerical results show that the computation of the complete solutions can be achieved with high accuracy and efficiency. 展开更多
关键词 functionally graded material(FGM) transverse isotropy ELASTICITY closedform singular solution Green's function point load vector
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Variable Parameter Nonlinear Control for Maximum Power Point Tracking Considering Mitigation of Drive-train Load 被引量:2
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作者 Zaiyu Chen Minghui Yin +3 位作者 Lianjun Zhou Yaping Xia Jiankun Liu Yun Zou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第2期252-259,共8页
Since mechanical loads exert a significant influence on the life span of wind turbines, the reduction of transient load on drive-train shaft has received more attention when implementing a maximum power point tracking... Since mechanical loads exert a significant influence on the life span of wind turbines, the reduction of transient load on drive-train shaft has received more attention when implementing a maximum power point tracking U+0028 MPPT U+0029 controller. Moreover, a trade-off between the efficiency of wind energy extraction and the load level of drive-train shaft becomes a key issue. However, for the existing control strategies based on nonlinear model of wind turbines, the MPPT efficiencies are improved at the cost of the intensive fluctuation of generator torque and significant increase of transient load on drive train shaft. Hence, in this paper, a nonlinear controller with variable parameter is proposed for improving MPPT efficiency and mitigating transient load on drive-train simultaneously. Then, simulations on FAST U+0028 Fatigue, Aerodynamics, Structures, and Turbulence U+0029 code and experiments on the wind turbine simulator U+0028 WTS U+0029 based test bench are presented to verify the efficiency improvement of the proposed control strategy with less cost of drive-train load. © 2017 Chinese Association of Automation. 展开更多
关键词 AERODYNAMICS Controllers Economic and social effects Maximum power point trackers Wind power Wind turbines
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Effect of loading point position on fracture mode of rock
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作者 饶秋华 孙宗颀 +2 位作者 徐继成 王桂尧 张静宜 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期764-767,共4页
Anti symmetric four point bending specimen with different loading point positions was used to study effect of loading point position on fracture mode of rock in order to explore a feasible method for achieving Mode Ⅱ... Anti symmetric four point bending specimen with different loading point positions was used to study effect of loading point position on fracture mode of rock in order to explore a feasible method for achieving Mode Ⅱ fracture and determining Mode Ⅱ fracture toughness of rock, K ⅡC . Numerical and experimental results show that the distance between the inner and outer loading points, L 1+ L 2, has a great influence on stresses at notch tip and fracture mode. When L 1+ L 2>0.5 L or 0.1 L < L 1+ L 2<0.5 L , maximum principal stress σ 1 exceeds the tensile strength σ t. The ratio of τ max / σ 1 is relatively low or high and thus Mode Ⅰ or mixed mode fracture occurs. When L 1+ L 2< 0.1 L , σ 1 is smaller than σ t and the ratio of τ max / σ 1 is much higher, which facilitates the occurrence of Mode Ⅱ fracture. 展开更多
关键词 fracture mode loading point position stress analysis ROCK
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Estimating Unconfined Compressive Strength of Sedimentary Rocks in United Arab Emirates from Point Load Strength Index 被引量:2
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作者 Hussain Salah Maher Omar Abdallah Shanableh 《Journal of Applied Mathematics and Physics》 2014年第6期296-303,共8页
In this paper, three rock types including Sandstone, Mudstone, and Crystalline Gypsum were part of a laboratory study conducted to develop a dataset for predicting the unconfined compressive strength of UAE intact sed... In this paper, three rock types including Sandstone, Mudstone, and Crystalline Gypsum were part of a laboratory study conducted to develop a dataset for predicting the unconfined compressive strength of UAE intact sedimentary rock specimens. Four hundred nineteen rock samples from various areas along the coastal region of the UAE were collected and tested for the development of this dataset and evaluation of models. From the statistical analysis of the data, regression equations were established among rock parameters and correlations were expressed and compared by the ones proposed in literature. 展开更多
关键词 SEDIMENTARY ROCKS UNITED Arab Emirates Unconfined COMPRESSIVE STRENGTH point load STRENGTH INDEX Regression Analysis
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Strength and failure characteristics of marble spheres subjected to paired point loads
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作者 Rui Zhao Ming Tao +2 位作者 Wenzhuo Cao Kun Du Jianbo Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2280-2290,共11页
Failure of irregular rock samples may provide implications in the rapid estimation of rock strength,which is imperative in rock engineering practice.In this work,analytical,experimental and numerical investigations we... Failure of irregular rock samples may provide implications in the rapid estimation of rock strength,which is imperative in rock engineering practice.In this work,analytical,experimental and numerical investigations were carried out to study the mechanical properties and failure characteristics of rock spheres under paired point loads.Analytical solutions indicted that with the increase in sample size(contact angle)and decrease in Poisson’s ratio,the uneven tensile stress in theta direction decreased.Then laboratory experiments were carried out to investigate the load characteristics and failure mode of spherical marble samples with different sizes subjected to a pair of diametral point loads.The discrete element method(DEM)was adopted to study the failure process of rock spheres.The effect of the sphere diameter on the point load contact angle was examined in terms of peak load,crushed zone distribution and energy dissipation.Experimental and numerical results showed that the samples primarily fail in tension,with crushed zones formed at both loading points.With increase in the sample size,the contact angle,crushed area and total work increase.As the specimen diameter increases from 30 mm to 50 mm,the peak load on the specimen increases from 3.6 kN to 8.8 kN,and the percentage of crushed zone(ratio of crushing zone to sample radius,d/r)increased from 0.191 to 0.262.The results of the study have implications for understanding the failure of irregular rock specimens under point loading conditions and their size effects. 展开更多
关键词 Rock sphere point load Contact angle Energy dissipation Failure analysis
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Nanoindentation Models of Monolayer Graphene and Graphyne under Point Load Pattern Studied by Molecular Dynamics
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作者 向浪 吴建 +2 位作者 马双英 王芳 张凯旺 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期108-111,共4页
Molecular dynamics simulations are performed to study the nanoindentation models of monolayer suspended graphene and graphyne. Fullerenes are selected as indenters. Our results show that Young's modulus of monolayer-... Molecular dynamics simulations are performed to study the nanoindentation models of monolayer suspended graphene and graphyne. Fullerenes are selected as indenters. Our results show that Young's modulus of monolayer-thick graphyne is almost half of that of graphene, which is estimated to be 0.50 TPa. The mechanical properties of graphene and graphyne are different in the presence of strain. A pre-tension has an important effect on the mechanical properties of a membrane. Both the pre-tension and Young's modulus plots demonstrate index behavior. The toughness of graphyne is stronger than that of graphene due to Young's modulus magnitude. Young's moduli of graphene and graphyne are almost independent of the size ratio of indenter to membrane. 展开更多
关键词 Nanoindentation Models of Monolayer Graphene and Graphyne under point load Pattern Studied by Molecular Dynamics
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Simulation on the Time Progress of the Non-Point Source Pollution Load in Initial Stage Runoff for Small Watershed
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作者 Mingyuan Sun Tiantian Liu +2 位作者 Bo Chen Yi Zhang Longxi Han 《World Journal of Engineering and Technology》 2017年第3期62-70,共9页
Taking a reservoir in South China as an example, we use rainfall-runoff unit hydrograph method to analyze the time changing process of surface runoff inflow, which generated by typical design rainfall. On the basis of... Taking a reservoir in South China as an example, we use rainfall-runoff unit hydrograph method to analyze the time changing process of surface runoff inflow, which generated by typical design rainfall. On the basis of time series data of flow and water quality in control section of the main rivers in Xili Reservoir, we establish mathematical response relation between non-point source pollutants flux, such as flux of COD, flux of NH3-H, in catchment area of control section and runoff. Then we simulate the time dynamic change progress of non-point source pollution load which generate with the initial stage runoff that generated by design rainfall and flow into reservoir. It can provide technical parameters for the design of non-point source which generate from early runoff treatment project. 展开更多
关键词 Small WATERSHED INITIAL RUNOFF Non-point Source POLLUTION load TIME Change Process
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Contact Force Distribution and Static Load-carrying Capacity of Large Size Double Row Four-point Contact Ball Bearing 被引量:7
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作者 Yan-shuang WANG Qian-qian YUAN 《Defence Technology(防务技术)》 SCIE EI CAS 2013年第4期229-236,共8页
Clearance not only affects the startup torque,rotation precision and stiffness of bearing,but also affects the load distribution,load-carrying capacity and life of bearing.A computational model in which the clearance ... Clearance not only affects the startup torque,rotation precision and stiffness of bearing,but also affects the load distribution,load-carrying capacity and life of bearing.A computational model in which the clearance of bearing is first included is presented for determining the contact force distribution and static load-carrying capacity of a double row four-point contact ball bearing which is subjected to the combined radial,axial and overturning moment loadings.The relation between the negative axial clearance and the contact force distribution is analyzed.The static load-carrying capacity curves are established,and the effects of the changes in negative axial clearance,curvature radius coefficient of raceway groove and initial contact angle on the static load-carrying capacity are analyzed.The results show that,with the increase in the absolute value of negative clearance,the maximum contact load decreases first and then increases.The clearance values in the range of 0.2 mme0 mm have little effect on the static load-carrying capacity of bearing.With the increase in the curvature radius coefficient of raceway groove and the decrease in the initial contact angle,the static load capacity of bearing decreases. 展开更多
关键词 四点接触球轴承 承载能力 接触力 静态 双排 大尺寸 轴向游隙 轴向间隙
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Analysis on the Status of Agricultural Non-point Source Pollution in Xinan River Basin 被引量:10
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作者 徐文 罗建中 《Meteorological and Environmental Research》 CAS 2010年第12期79-81,共3页
Taking Xinan River basin as research object,the status of agricultural non-point source pollution was analyzed based on field survey,as well as the effect of fertilizer and pesticide leaching and runoff,livestock and ... Taking Xinan River basin as research object,the status of agricultural non-point source pollution was analyzed based on field survey,as well as the effect of fertilizer and pesticide leaching and runoff,livestock and poultry breeding and rural domestic pollution on non-point source TN and TP.At last,some technical countermeasures of controlling non-point source pollution were put forward according to the characteristics of agricultural non-point source pollution in Xinan River basin. 展开更多
关键词 Xinan River basin Agricultural non-point source pollution Pollution loading Control measure China
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基于Seq2point和SERNet的非侵入式负荷分解及识别 被引量:2
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作者 程志友 储著增 +2 位作者 杨猛 章杨凡 王林茂 《安徽大学学报(自然科学版)》 CAS 北大核心 2022年第4期38-44,共7页
为了提高负荷的分解及识别准确度,提出基于序列到点(sequence-to-point,简称Seq2point)和挤压与激励的残差网络(squeeze-and-excitation residual network,简称SERNet)的非侵入式负荷分解和识别方法.使用残差网络提取信息,引入注意力机... 为了提高负荷的分解及识别准确度,提出基于序列到点(sequence-to-point,简称Seq2point)和挤压与激励的残差网络(squeeze-and-excitation residual network,简称SERNet)的非侵入式负荷分解和识别方法.使用残差网络提取信息,引入注意力机制挤压和激励网络,对提取的信息进行自适应校准.通过全连接网络映射得到负荷分解结果,进而识别负荷.算例分析结果表明:与其他4种方法比较,该方法有更高的分解及识别准确度. 展开更多
关键词 非侵入式负荷分解 滑动窗口法 序列到点 残差学习 挤压和激励网络
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Assessing effects of “source-sink” landscape on non-point source pollution based on cell units of a small agricultural catchment 被引量:5
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作者 WANG Jin-liang CHEN Cheng-long +4 位作者 NI Jiu-pai XIE De-ti GUO Xi LUO Zhi-jun ZHAO Yue 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2048-2062,共15页
Ascertaining the relationship between "source-sink" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To ... Ascertaining the relationship between "source-sink" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To reveal the relationships between "sourcesink" landscape and NPS pollution based on cell units of a small catchment in the Three Gorges Reservoir Region(TGRR), the runoff and nutrient yields were simulated first by rainfall events on a cell unit scale based on the Annualized AGricultural Non-Point Source Pollution Model(AnnAGNPS). Landscape structure and pattern were quantified with "sourcesink" landscape indicators based on cell units including landscape area indices and locationweighted landscape indices. The results showed that:the study case of small Wangjiagou catchment highlighted a good prediction capability of runoff and nutrient export by the AnnAGNPS model. Throughout the catchment, the spatial distribution trends of four location-weighted landscape indices were similar to the trends of simulated total nitrogen(TN) and total phosphorus(TP), which highlighted the importance of spatial arrangement of "source" and "sink" landscape types in a catchment when estimating pollutant loads. Results by Pearson correlation analysis indicated that the location-weighted landscape index provided a more comprehensive account of multiple factors, and can better reflect NPS-related nutrient loss than other landscape indices applied in single-factor analysis. This study provides new findings for applying the "source-sink" landscape indices based on cell units in small catchments to explain the effect of "source-sink" landscape on nutrient export based on cell unit, and helps improve the understanding of the correlation between "source-sink" landscape and NPS pollution. 展开更多
关键词 Nutrient load Non-point SOURCE pollution SOURCE SINK LANDSCAPE index SMALL catchment
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Load-Aware Offloading Strategy in Two-Tier Heterogeneous Network 被引量:5
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作者 Jianyuan Feng Zhiyong Feng Zhiqing Wei 《China Communications》 SCIE CSCD 2016年第8期148-158,共11页
Although small cell offloading technology can alleviate the congestion in macrocell, aggressively offloading data traffic from macrocell to small cell can also degrade the performance of small cell due to the heavy lo... Although small cell offloading technology can alleviate the congestion in macrocell, aggressively offloading data traffic from macrocell to small cell can also degrade the performance of small cell due to the heavy load. Because of collision and backoff, the degradation is significant especially in network with contention-based channel access, and finally decreases throughput of the whole network. To find an optimal fraction of traffic to be offloaded in heterogeneous network, we combine Markov chain with the Poisson point process model to analyze contention-based throughput in irregularly deployment networks. Then we derive the close-form solution of the throughput and find that it is a function of the transmit power and density of base stations.Based on this, we propose the load-aware offloading strategies via power control and base station density adjustment. The numerical results verify our analysis and show a great performance gain compared with non-load-aware offloading. 展开更多
关键词 heterogeneous networks offloading strategies load-aware Poisson point process Markov chain throughput maximization CSMA
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Distortionless Lossy Transmission Lines Terminated by in Series Connected <i>RCL</i>-Loads 被引量:1
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作者 Vasil G. Angelov Marin Hristov 《Circuits and Systems》 2011年第4期297-310,共14页
The paper deals with a lossy transmission line terminated at both ends by non-linear RCL elements. The mixed problem for the hyperbolic system, describing the transmission line, to an initial value problem for a neutr... The paper deals with a lossy transmission line terminated at both ends by non-linear RCL elements. The mixed problem for the hyperbolic system, describing the transmission line, to an initial value problem for a neutral equation is reduced. Sufficient conditions for the existence and uniqueness of periodic regimes are formulated. The proof is based on the finding out of suitable operator whose fixed point is a periodic solution of the neutral equation. The method has a good rate of convergence of the successive approximations even for high frequencies. 展开更多
关键词 LOSSY Transmission Line RCL-Nonlinear loads Fixed point PERIODIC Solution
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Umbilical Cable Recovery Load Analysis 被引量:1
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作者 闫澍旺 贾沼霖 +1 位作者 封晓伟 李世涛 《China Ocean Engineering》 SCIE EI CSCD 2013年第3期351-358,共8页
Umbilical cable is a kind of integrated subsea cable widely used in the exploration and exploitation of oil and gas field. The severe ocean environment makes great challenges to umbilical maintenance and repair work. ... Umbilical cable is a kind of integrated subsea cable widely used in the exploration and exploitation of oil and gas field. The severe ocean environment makes great challenges to umbilical maintenance and repair work. Damaged umbilical is usually recovered for the regular operation of the offshore production system. Analysis on cables in essence is a two-point boundary problem. The tension load at the mudline must be known first, and then the recovery load and recovery angle on the vessel can be solved by use of catenary equation. The recovery analysis also involves umbilical- soil interaction and becomes more complicated. Calculation methods for recovery load of the exposed and buried umbilical are established and the relationship between the position of touch down point and the recovery load as well as the recovery angle and recovery load are analyzed. The analysis results provide a theoretical reference for offshore on-deck operation. 展开更多
关键词 umbilical cable clay seabed catenary equation touch down point recovery load
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Method for calculating non-point source pollution distribution in plain rivers 被引量:7
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作者 Long-xi HAN Fei HUO Juan SUN 《Water Science and Engineering》 EI CAS 2011年第1期83-91,共9页
The land area in a river network is divided into certain-scale square cells for the sake of precision, and, based on the physical mechanisms of rainfall-runoff processes and runoff pollution, the non-point source poll... The land area in a river network is divided into certain-scale square cells for the sake of precision, and, based on the physical mechanisms of rainfall-runoff processes and runoff pollution, the non-point source pollution from cells is estimated using the export coefficients of different land use types. The non-point source pollution from a land cell should all go into the closest fiver reach, so it is distributed according to the terrain of the plain river network area and the positions of land cells and river network reaches. A relationship between a single land cell and its pollution-receiving reach can be determined using this system. In view of the above, a spatial distribution model of the rainfall runoff and non-point source pollution in reaches of a plain river network area was established. This model can provide technological support for further research on the dynamic effects of non-point source pollution on water quality. 展开更多
关键词 non-point source pollution pollution loads export coefficients plain river network
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Nitrogen forms and pollution load of Dianchi Lake inflow river runoff in rainy season
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作者 SU Bin SHI Zheng-tao +4 位作者 SHEN Ying-jia FENG Ze-bo XIAO Dong-dong KONG Yan ZHAO Yang 《Ecological Economy》 2016年第4期311-319,共9页
With the control of point source pollution in Dianchi Lake basin, and the expansion of Kunming city, non-point source pollution has become the main source pollution of urban water environment and Dianchi Lake. To reve... With the control of point source pollution in Dianchi Lake basin, and the expansion of Kunming city, non-point source pollution has become the main source pollution of urban water environment and Dianchi Lake. To reveal the nitrogen pollution characteristics in watershed, this research selected key monitoring points and sections at Baoxiang river basin in rainy season which is the peak transported time of non-point source pollution, the nitrogen and hydrological indicators are monitored systematically. The different forms of nitrogen are analyzed, the pollution load of nitrogen are calculated and studied at cardinal sections; combined with the literature data, we compared the water nitrogen characteristics of Dianchi basin and Taihu basin, the main results are as follows:(1) In summer, water nitrogen form of Baoxiang river in the Caohe area is dominated by nitrate nitrogen, while in other areas it is dominated by ammonia nitrogen which is accounted for 31%-50% of total nitrogen;(2) The water pollution loads of Baoxiang river tended to increase from upstream to downstream, from June to August the total nitrogen pollution mainly comes from urban areas and the pollution load is 166.408 t;(3) In Dianchi Lake watershed and Taihu Lake watershed nitrogen concentration of inflow river is higher than that of the lake, nitrate nitrogen concentration between inflow river and lake shows a little difference, while ammonia nitrogen concentration of inflow river is higher than that of the lake. The results can provide the theoretical basis for nonpoint source pollution control and urban water environment planning and improvement in Dianchi Lake Basin. 展开更多
关键词 Dianchi Lake basin NITROGEN forms of occurrence pollution load non-point pollution
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