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The uncertainty of the Shannon entropy model for shear stressdistribution in circular channels 预览
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作者 Amin Kazemian-Kale-Kale Hossein Bonakdari +1 位作者 Azadeh Gholami Bahram Gharabaghi 《国际泥沙研究:英文版》 SCIE 2020年第1期57-68,共12页
The shear stress distribution at alluvial stream beds and banks is one of the essential parameters in channel stability analysis.In the current paper,a novel uncertainty analysis method based on the framework of a Bay... The shear stress distribution at alluvial stream beds and banks is one of the essential parameters in channel stability analysis.In the current paper,a novel uncertainty analysis method based on the framework of a Bayesian Forecasting System(BFS)is presented to evaluate the Shannon entropy model for prediction of the shear stress distribution in both circular rigid-bed and alluvial-bed channels.The Johnson and Box-Cox transformation functions were applied to select the optimum sample size(SS)and corresponding transformation factor for determining a 95%confidence bound(CB)for the Shannon entropy model.The Shapiro-Wilk(SW)test is applied according to the SS used to evaluate the power of transformation functions in the data normalization.The results show that the error distribution between predicted and experimental shear stress values generated using the Box-Cox transformation is closer to a Gaussian distribution than the generated using the Johnson transformation.The indexes of the percentage of the experimental values within the CB(Nin)and Forecast Range Error Estimate(FREE)are applied for the uncertainty analyses.The lower values of FREE equal to 1.724 in the circular rigid-bed channel represent the low uncertainty of Shannon entropy in the prediction of shear stress values compared to the uncertainty for the circular alluvial-bed channel with a FREE value equal to 7.647. 展开更多
关键词 Uncertainty analysis Shear stress distribution Shannon entropy Confidence bound Johnson transformation Box-Cox transformation Circular with sediment bed
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The inverse Bremsstrahlung absorption in the presence of Maxwellian and non-Maxwellian electrons
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作者 Mehdi Sharifian Fatemeh Ghoveisi +1 位作者 Leila Gholamzadeh Narges Firouzi Farrashbandi 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第10期435-440,共6页
Inverse Bremsstrahlung absorption(IBA) of an intense laser field in plasma containing Maxwellian and nonMaxwellian(with Kappa and q-nonextensive distribution functions) electrons is studied analytically. Our results s... Inverse Bremsstrahlung absorption(IBA) of an intense laser field in plasma containing Maxwellian and nonMaxwellian(with Kappa and q-nonextensive distribution functions) electrons is studied analytically. Our results show that IBA decreases with an increase in temperature at high intensities and a decrease in plasma density for all kinds of distribution functions. Another striking result is that IBA is independent of the laser intensity at low intensity but is dependent on it when the intensity is going to rise. Also, it could be find that the behavior of the absorption as the function of laser intensity for the Kappa distribution with κ= 10 at low intensity is close to that for the Maxwellian distribution, but at high intensity it is close to that in the presence of q-nonextensive electrons with q = 0.9. These results provide insights into the inverse Bremsstrahlung absorption in the laser-plasma interactions. 展开更多
关键词 laser-plasmas interaction inverse BREMSSTRAHLUNG ABSORPTION Maxwellian DISTRIBUTION KAPPA DISTRIBUTION q-nonextensive DISTRIBUTION
Multi-Model Based PSO Method for Burden Distribution Matrix Optimization With Expected Burden Distribution Output Behaviors 预览
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作者 Yong Zhang Ping Zhou Guimei Cui 《自动化学报:英文版》 CSCD 2019年第6期1506-1512,共7页
Burden distribution is one of the most important operations, and also an important upper regulation in blast furnace(BF) iron-making process. Burden distribution output behaviors(BDOB) at the throat of BF is a 3-dimen... Burden distribution is one of the most important operations, and also an important upper regulation in blast furnace(BF) iron-making process. Burden distribution output behaviors(BDOB) at the throat of BF is a 3-dimensional spatial distribution produced by burden distribution matrix(BDM),including burden surface output shape(BSOS) and material layer initial thickness distribution(MLITD). Due to the lack of effective model to describe the complex input-output relations,BDM optimization and adjustment is carried out by experienced foremen. Focusing on this practical challenge, this work studies complex burden distribution input-output relations, and gives a description of expected MLITD under specific integral constraint on the basis of engineering practice. Furthermore, according to the decision variables in different number fields, this work studies optimization of BDM with expected MLITD, and proposes a multi-mode based particle swarm optimization(PSO) procedure for optimization of decision variables. Finally, experiments using industrial data show that the proposed model is effective, and optimized BDM calculated by this multi-model based PSO method can be used for expected distribution tracking. 展开更多
关键词 Blast furnace burden distribution burden distribution matrix(BDM) burden distribution output behaviors(BDOB) distributed parameter system particle swarm optimization(PSO)
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A generalization of Poisson-Sujatha distribution and its applications to ecology
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作者 Rama Shanker Kamlesh Kumar Shukla 《生物数学学报:英文版》 2019年第2期37-47,共11页
A generalization of Poisson Sujatha distribution(AGPSD),which includes Poisson-Lindley distribution(PLD)and Poisson-Sujatha distribution(PSD)as particular cases,has been proposed and studied.Its moments and moments-ba... A generalization of Poisson Sujatha distribution(AGPSD),which includes Poisson-Lindley distribution(PLD)and Poisson-Sujatha distribution(PSD)as particular cases,has been proposed and studied.Its moments and moments-based measures including coefficient of variation,skewness,kurtosis and index of dispersion have been obtained and their behaviors have been discussed.The estimation of its parameters has been discussed with maximum likelihood estimation.The applications of the proposed distribution has been explained through two examples of count data from ecology and the goodness of fit of the distribution has been compared with Poisson distribution,PLD and PSD. 展开更多
关键词 Sujatha DISTRIBUTION Poisson-Sujatha DISTRIBUTION GENERALIZATION of Sujatha DISTRIBUTION MOMENTS and moments-based measures maximum LIKELIHOOD estimation APPLICATIONS
Multiple Cassava Viruses’ Co-Infections and Resurgence of Pests Are Leading to Severe Symptoms and Yield Losses on Cassava in the South-Kivu Region, Democratic Republic of Congo 预览
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作者 E. B. Bisimwa D. R. Birindwa +4 位作者 M. O. Yomeni N. Rudahaba K. Byamungu S. Winter C. Bragard 《美国植物学期刊(英文)》 2019年第11期1969-1988,共20页
A survey was completed during the last five years (2014-2018) to update and assess changes in the cassava pests and diseases occurrence as well as to understand how these changes occur regarding the recent new viruses... A survey was completed during the last five years (2014-2018) to update and assess changes in the cassava pests and diseases occurrence as well as to understand how these changes occur regarding the recent new viruses spread under a climate change context in the South-Kivu region, Democratic Republic of Congo. The eight territories of South-Kivu were surveyed during the rainy seasons from 2015 until 2017 except for Uvira and Fizi where data were recorded in 2018 regarding the prevalence of unstable agro ecological factors which may influence pest and diseases dynamic in these two territories. During the data collection, pests and disease incidence and severity were recorded as well as the sampling of cassava leaves for molecular viruses’ detection. The recorded data showed that Cassava mosaic disease (CMD) remains the most encountered disease (75% - 80%) and its vector (the whitefly Bemisia tabaci) the most important pest (10 - 18 adult whiteflies per leaf). The major changes were recorded for Cassava brown streak disease, recently reported in the region, for which a significant increase was recorded, with not reports before 2012 to 70% - 80% incidence in 2018 in the Ruzizi plain area (Uvira and Fizi). Molecular detection revealed a coexistence of both two viruses, the cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) in single and mixed infections. Co-infections cassava mosaic and cassava brown streak diseases were frequently recorded resulting in severe expression leaves’ symptoms and tuber yields’ losses. Common pests and diseases considered as minor have drastically become serious threat to cassava production by increasing both their incidence and severity values. The cassava bacterial blight (20%), cassava green mite (20% - 70%), cassava mealy bugs and cassava grasshoppers were recorded as a great challenge in relation with an occurrence of long dry season resulting in four consecutive dry months without rain. The high occurrence of CBSD on new CMD-resistant varieties has 展开更多
关键词 CASSAVA Genotypes Distribution Climate Factors South-Kivu Re-Emergence WHITEFLY
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规范化管理中药房饮片及处方质量控制对照研究
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作者 刘海兰 《实用中医内科杂志》 2019年第3期66-67,共2页
[目的]观察规范化管理中药房饮片及处方质量控制效果。[方法]使用对照方法,将800例中药房处方按实施中药质量规范化管理前后分为两组。实施前400例常规管理方式。实施后400例规范化管理。观测规范化管理中药房药品配发准确率、退换药品... [目的]观察规范化管理中药房饮片及处方质量控制效果。[方法]使用对照方法,将800例中药房处方按实施中药质量规范化管理前后分为两组。实施前400例常规管理方式。实施后400例规范化管理。观测规范化管理中药房药品配发准确率、退换药品率、平均取药时间、患者满意度。[结果]药品配发准确率、退换药品率实施后优于实施前(P<0.01),平均取药时间实施后短于实施前(P<0.01),患者满意度实施后优于实施前(P<0.01)。[结论]规范化管理中药房可有效对饮片及处方质量控制,效果满意,值得推广。 展开更多
关键词 规范化管理 中药房 饮片 处方 质量控制 采购 存储 配发 药品配发准确率 退换药品率 平均取药时间 对照研究
Research on Distribution Network Automation and Distribution Network Planning Mode 预览
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作者 Xuan Chen 《现代电子技术(英文)》 2019年第1期27-30,共4页
Based on the research of distribution network automation and distribution network planning mode, the analysis of the significance of urban distribution network automation must be performed at the first place. Combined... Based on the research of distribution network automation and distribution network planning mode, the analysis of the significance of urban distribution network automation must be performed at the first place. Combined with the problems existing in China’s current distribution network, it is concluded that, establish effective hardware support system, data sharing and feeder automation to ensure automation safety;strengthen power distribution and power line material testing to improve distribution automation system and distribution network planning;research methods of improving the professional skills and comprehensive quality of professionals. 展开更多
关键词 DISTRIBUTION NETWORK AUTOMATION DISTRIBUTION NETWORK PLANNING Mode RESEARCH
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Effects of vegetation patch density on flow velocity characteristics in an openchannel 预览
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作者 Wen-qi Li Dan Wang +1 位作者 Jun-li Jiao Ke-jun Yang 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第5期1052-1059,共8页
The aquatic plants are often found in natural rivers,and they affect the channel flow structure significantly.To study the effects of the vegetation density a(the frontal area per volume)on the flow velocity character... The aquatic plants are often found in natural rivers,and they affect the channel flow structure significantly.To study the effects of the vegetation density a(the frontal area per volume)on the flow velocity characteristics,rigid bamboo circular cylinders are chosen as the model emergent vegetation.In the experiments,the density of the vegetation takes various values while all other flow parameters are kept constant.A 3-D acoustic Doppler velocimeter(ADV)is used to measure the local flow velocities for different vegetation densities.The results show that the existence of the vegetation patch leads to an increase of the depth-averaged velocity on the right and left sides behind the vegetation patch,and it increases monotonically with the vegetation density.For different vegetation densities,the lateral distribution of the stream-wise velocity behind the vegetation patch follows approximately an S-shaped profile when a≤60 m-1,and a logarithmic profile if a>60 m-1.The vertical distribution of the stream-wise velocity along the channel varies with the vegetation density and also follows an S-shaped distribution in a certain range,with the locations and the ranges being affected by the vegetation density. 展开更多
关键词 Vegetation density stream-wise velocity depth-averaged velocity lateral distribution longitudinal distribution open channel
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Monitoring of Cadmium Contaminated Soil in Kvemo Kartli Region (Republic of Georgia) 预览
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作者 Guranda Avkopashvili Marika Avkopashvili +2 位作者 Irakli Avkopashvili Khvicha Kazaishvi Nikoloz Tsikaridze 《地质学期刊(英文)》 2019年第3期187-192,共6页
Environmental pollution increases from year to year and concentrations of pollutants reach a colossal point, which ultimately affects the health of the living organisms. Industrial pollution and old mining methods are... Environmental pollution increases from year to year and concentrations of pollutants reach a colossal point, which ultimately affects the health of the living organisms. Industrial pollution and old mining methods are one of the sources of harmful agents in the environment. It is important to study and monitor environmental pollution in dynamics. During several years we have been researching heavy metals distribution in soils in the South East part of Georgia. “RMG Gold and Copper” mine in Kazreti is one of the biggest enterprises in Georgia. As a result of open-cast mining aerosols containing heavy metals are ejected which causes harmful effects of the environment. Within this research 21 villages in Bolnisi and Dmanisi municipalities were investigated;analysis of agricultural soils showed that the concentration of cadmium in the vicinity of the enterprise was significantly increased and exceeded maximum allowed concentrations. Through the wind, cadmium-containing dust spreads out to the 22 kilom 展开更多
关键词 CADMIUM Distribution Soil CONTAMINATION GOLD MINE
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Ecological Sustainability of Detar (<i>Detarium senegalense</i>J. F. Gmel) in Togo (West Africa) 预览
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作者 Fifonsi Ayélé Dangbo Kossi Adjonou +1 位作者 Kouami Kokou Juergen Blaser 《美国植物学期刊(英文)》 2019年第3期417-432,共16页
Detarium senegalense J. F. Gmel., of the family of Fabaceae is one of the most exploited tree species in Togo. However, there are only few scientific studies on the distribution of this specie. This study is a contrib... Detarium senegalense J. F. Gmel., of the family of Fabaceae is one of the most exploited tree species in Togo. However, there are only few scientific studies on the distribution of this specie. This study is a contribution to the promotion of multi-purpose tree species in Togo with particular emphasis on a better knowledge of Detarium senegalense. It provides data on the ecology of the specie and his state of regeneration. The data on the specie are based on sample plots in the areas identified as hosts of the specie in Togo. A total of 77 circular plots of 1000 m2 (17.8 m radius) were established in ecological zones II, IV and V of Togo. The dendrometric parameters identified are: the total height and diameter at breast height (DBH) of Detarium senegalense and of all species found in each plot. Detarium senegalense trees of DBH < 10 cm are considered as potential regenerations. Detarium senegalense is more abundant in zones IV (forest area), followed by zone II. In zone V, Detarium senegalense is located only in the forest of “Have”. The structure of Detarium senegalense has a bell-shaped distribution with predominance of trees with large and intermediate diameters ranging between 30 and 70 cm. Trees of small DBH (Detarium senegalense occurs. This indicates a low regeneration rate of the specie. However, the structure of all species inventoried has a negative exponential distribution with predominance of small diameter trees. The sustainable management of Detarium senegalense in the forest can only be secured through a sustainable harvesting of seeds and actives promotion of natural regeneration. 展开更多
关键词 Detarium senegalense Distribution ECOLOGY Non-Timber Forest Products TOGO
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The Genus <i>Dracocephalum</i>L. in the Phytogeographical Regions of Uzbekistan 预览
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作者 Nilufar S. Abdullaeva Olimjon K. Khodzhimatov Dilnoz E. Azimova 《美国植物学期刊(英文)》 2019年第9期1527-1535,共9页
The article provides an analysis of the distribution of fourteen species belonging to seven sections of the genus Dracocephalum in the phytogeographical regions of Uzbekistan.
关键词 Dracocephalum FLORA Uzbekistan DISTRIBUTION Phytogeographical REGIONS
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Reactive power deployment and cost benefit analysis in DNO operated distribution electricity markets with D-STATCOM
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作者 Atma Ram GUPTA Ashwani KUMAR 《能源前沿:英文版》 CSCD 2019年第1期86-98,共13页
The aim of this paper is to analyze unbalanced radial distribution systems(UBRDS)with the distribution static compensator(D-STATCOM).The main objectives of this paper are D-STATCOM allocation in UBRDS with an objectiv... The aim of this paper is to analyze unbalanced radial distribution systems(UBRDS)with the distribution static compensator(D-STATCOM).The main objectives of this paper are D-STATCOM allocation in UBRDS with an objective of providing reactive power support to enhance voltage profile and reduce line losses of the distribution network,determination of optimal D-STATCOM rating subjected to minimization of total cost,and impact of D-STATCOM placement on improving power factor and savings in cost of energy loss.The analysis is conducted on a large industrial load model with light,medium and high loading scenarios.Further,the impact of load growth is also considered for better planning of the power distribution system.The results are obtained on standard 25-bus UBRDS to check the feasibility of the proposed methodology. 展开更多
关键词 unbalanced DISTRIBUTION system D-STATCOM VOLTAGE sensitivity index LOAD models LOAD growth DISTRIBUTION network operator(DNO)
Distribution of Vascular Plants along Altitudinal Gradients in Hoang Lien National Park, Vietnam 预览
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作者 Mac Thi Yen Shiping Xing +4 位作者 Hairong Han Xiaoqin Cheng Do Thi Thao Sajid Hussain Sher Shah 《林学期刊(英文)》 2019年第4期407-418,共12页
The present study was conducted to examine the distributional characteristics of floral communities along the altitudinal gradients in Hoang Lien National Park (HLNP), located in Lao Cai province, Vietnam. We recorded... The present study was conducted to examine the distributional characteristics of floral communities along the altitudinal gradients in Hoang Lien National Park (HLNP), located in Lao Cai province, Vietnam. We recorded the relatively abundant flora system with 3252 species (including 361 endemic species and 237 endangered species), belonging to 1126 genera, 230 families and 6 different phyla. Methodology of sampling, specimen collection and identification, statistical analysis are simultaneously used for investigating the complex changes of composition and richness of plant assemblages. The study results indicated the divisions in quantity and composition, especially differentiation of endemic and rare species in accordance with altitudinal gradients. 展开更多
关键词 Hoang LIEN National Park Altitudinal Gradients FLORA Diversity DISTRIBUTION ENDEMIC PLANT Rare PLANT Vascular PLANT
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Gas–liquid mass transfer and flow phenomena in a peirce–smith converter: A numerical model study 预览
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作者 Hong-liang Zhao Xing Zhao +2 位作者 Liang-zhao Mu Li-feng Zhang Li-qiang Yang 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第9期1092-1104,共13页
A numerical model was established to simulate the flow field in a Peirce–Smith converter bath, which is extensively adopted in copper making. The mean phase and velocity distribution, circular area, and mean wall she... A numerical model was established to simulate the flow field in a Peirce–Smith converter bath, which is extensively adopted in copper making. The mean phase and velocity distribution, circular area, and mean wall shear stress were calculated to determine the optimal operation parameter of the converter. The results showed that the slag phase gathered substantially in the dead zone. The circular flow was promoted by increasing the gas flow rate, Q, and decreasing the nozzle height, h. However, these operations significantly aggravate the wall shear stress. Reducing the nozzle diameter, d, increases the injection velocity, which may accelerate the flow field. However, when the nozzle diameter has an interval design, the bubble behaviors cannot be combined, thus, weakening the injection efficiency. Considering the balance between the circular flow and wall shear stress in this model, the optimal operation parameters were Q = 30000–35000 m^3/h, h = 425–525 mm, and d = 40 & 50 mm. 展开更多
关键词 phase DISTRIBUTION velocity DISTRIBUTION wall shear stress Peirce–Smith CONVERTER
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Theoretical analytic model for RESURF AlGaN/GaN HEMTs
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作者 吴浩 段宝兴 +1 位作者 杨珞云 杨银堂 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第2期395-399,共5页
In this paper, we propose a two-dimensional(2D) analytic model for the channel potential and electric field distribution of the RESURF AlGaN/GaN high electron mobility transistors(HEMTs). The model is constructed by t... In this paper, we propose a two-dimensional(2D) analytic model for the channel potential and electric field distribution of the RESURF AlGaN/GaN high electron mobility transistors(HEMTs). The model is constructed by two-dimensional Poisson’s equation with appropriate boundary conditions. In the RESURF AlGaN/GaN HEMTs, we utilize the RESURF effect generated by doped negative charge in the AlGaN layer and introduce new electric field peaks in the device channels,thus, homogenizing the distribution of electric field in channel and improving the breakdown voltage of the device. In order to reveal the influence of doped negative charge on the electric field distribution, we demonstrate in detail the influences of the charge doping density and doping position on the potential and electric field distribution of the RESURF AlGaN/GaN HEMTs with double low density drain(LDD). The validity of the model is verified by comparing the results obtained from the analytical model with the simulation results from the ISE software. This analysis method gives a physical insight into the mechanism of the AlGaN/GaN HEMTs and provides reference to modeling other AlGaN/GaN HEMTs device. 展开更多
关键词 RESURF ALGAN/GAN HEMTS two-dimensional ANALYTIC model potential DISTRIBUTION electric field DISTRIBUTION
Leishmaniasis in the Argentine Republic: Temporal and geographical distribution from 2013 to 2017
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作者 GermanóMaría J Salomón María C +3 位作者 Neira Gisela Lozano Esteban Mackern-Oberti Juan P Cargnelutti Diego E 《亚太热带医药杂志:英文版》 SCIE CAS 2019年第7期300-305,共6页
Objective: To assess the temporal and geographical distribution of confirmed cases of cutaneous, mucocutaneous and visceral leishmaniasis in the Argentine Republic from 2013 to 2017. Methods: A retrospective study was... Objective: To assess the temporal and geographical distribution of confirmed cases of cutaneous, mucocutaneous and visceral leishmaniasis in the Argentine Republic from 2013 to 2017. Methods: A retrospective study was carried out using data collected from the Integrated Surveillance Bulletin database of the National System of Health Surveillance. Confirmed cases of cutaneous, mucocutaneous and visceral leishmaniasis up to the 52 nd epidemiological week of each year was included. Results: In the 5 years period, 1 295 confirmed leishmaniasis cases were reported in the Argentine Republic. One thousand twenty-eight(1 028) cases corresponded to cutaneous leishmaniasis(87.10%), being the most common type of leishmaniasis. Mucocutaneous leishmaniasis was in the second place in the country with 115 cases reported, mostly in the Northwest and Northeast regions. A total of 52 individuals with visceral leishmaniasis were identified and Misiones Province was the most affected. Conclusions: It is important to analyze the temporal and geographical distribution of leishmaniasis in order to provide an adequate management and surveillance. 展开更多
关键词 LEISHMANIASIS Epidemiology ARGENTINE REPUBLIC TEMPORAL DISTRIBUTION GEOGRAPHICAL DISTRIBUTION
Availability modeling for periodically inspection system with different lifetime and repair-time distribution
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作者 Junliang LI Yueliang CHEN +1 位作者 Yong ZHANG Hailiang HUANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第7期1667-1672,共6页
Availability is a main feature of design and operation of all engineering system. Recently,availability evaluation of periodical inspection systems with different structures is at the center of attention due to the wi... Availability is a main feature of design and operation of all engineering system. Recently,availability evaluation of periodical inspection systems with different structures is at the center of attention due to the wide application in engineering. In this paper, an analytical and probabilistic availability model for periodical inspection system is proposed by a new recursively algorithm,which can achieve limiting average availability and instantaneous availability of periodical inspection system under arbitrary lifetime and repair-time distributions. Then three application examples are presented, the systems lifetime and repair-time are respectively fellow exponential/exponential,Weibull/normal and Weibull/lognormal distribution. Finally, a Weibull/lognormal system is studied to analyze the dynamic relationship between inspection period and availability. The results indicate that the proposed approach can provide the technology support for improving system availability and determining reasonable inspection period. 展开更多
关键词 AVAILABILITY Inspection PERIOD LIFETIME DISTRIBUTION Reliability Repair-time DISTRIBUTION
ZmHAK5 and ZmHAK1 function in K^+ uptake and distribution in maize under low K^+ conditions^FA
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作者 Ya-Juan Qin Wei-Hua Wu Yi Wang 《植物学报:英文版》 SCIE CAS CSCD 2019年第6期691-705,共15页
Potassium (K^+) is an essential macronutrient for plant growth and development. Transporters from the KT/HAK/KUP family play crucial roles in K^+ homeostasis and cell growth in various plant species. However, their ph... Potassium (K^+) is an essential macronutrient for plant growth and development. Transporters from the KT/HAK/KUP family play crucial roles in K^+ homeostasis and cell growth in various plant species. However, their physiological roles in maize are still unknown. In this study, we cloned ZmHAKs and ZmHAKi and investigated their functions in maize (Zea mays L.). In situ hybridization showed that ZmHAKs was mainly expressed in roots, especially in the epidermis, cortex, and vascular bundle. ZmH AK5 was characterized as a high-affinity K^+ transporter. Loss of function of ZmHAK5 led to defective K^+ uptake in maize, under low K^+ conditions, whereas ZmHAK5-over-expressing plants showed increased K^+ uptake activity and improved growth. ZmHAKi was upregulated under low K^+ stress, as revealed by RT-qPCR. ZmHAKi mediated K^+ uptake when heterologously expressed in yeast, but its transport activity was weaker than that of ZmHAK5. Overexpression of ZmHAKi in maize significantly affected K^+ distribution in shoots, leading to chlorosis in older leaves. These findings indicate that ZmHAKs and ZmHAKi play distinct roles in K^+ homeostasis in maize, functioning in K^+ uptake and K^+ distribution, respectively. Genetic manipulation of ZmHAK5 may represent a feasible way to improve K^+ utilization efficiency in maize. 展开更多
关键词 ZmHAK5 and ZmHAK1 FUNCTION in K^+uptake and DISTRIBUTION in MAIZE under low K^+conditions^FA ZmHAK5 and ZmHAK1 FUNCTION in K^+uptake DISTRIBUTION
Large-Scale Estimation of Distribution Algorithms with Adaptive Heavy Tailed Random Pro jection Ensembles
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作者 Momodou L.Sanyang Ata Kabán 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第6期1241-1257,共17页
We present new variants of Estimation of Distribution Algorithms (EDA) for large-scale continuous optimisation that extend and enhance a recently proposed random projection (RP) ensemble based approach. The main novel... We present new variants of Estimation of Distribution Algorithms (EDA) for large-scale continuous optimisation that extend and enhance a recently proposed random projection (RP) ensemble based approach. The main novelty here is to depart from the theory of RPs that require (sub-)Gaussian random matrices for norm-preservation, and instead for the purposes of high-dimensional search we propose to employ random matrices with independent and identically distributed entries drawn from a t-distribution. We analytically show that the implicitly resulting high-dimensional covariance of the search distribution is enlarged as a result. Moreover, the extent of this enlargement is controlled by a single parameter, the degree of freedom. For this reason, in the context of optimisation, such heavy tailed random matrices turn out to be preferable over the previously employed (sub-)Gaussians. Based on this observation, we then propose novel covariance adaptation schemes that are able to adapt the degree of freedom parameter during the search, and give rise to a flexible approach to balance exploration versus exploitation. We perform a thorough experimental study on high-dimensional benchmark functions, and provide statistical analyses that demonstrate the state-of-the-art performance of our approach when compared with existing alternatives in problems with 1000 search variables. 展开更多
关键词 covariance adaptation estimation of distribution algorithm random projection ensemble T-DISTRIBUTION
Distribution of high-risk human papillomavirus genotype prevalence and attribution to cervical precancerous lesions in rural North China 预览
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作者 Shuang Zhao Xuelian Zhao +5 位作者 Shangying Hu Jessica Lu Xianzhi Duan Xun Zhang Feng Chen Fanghui Zhao 《中国癌症研究:英文版》 SCIE CAS CSCD 2019年第4期663-672,共10页
Objective: Precise prevention is more desired for cervical cancer due to the huge population, high prevalence of human papillomavirus(HPV) infection in China and the vision of screen-and-treat strategies in low-and mi... Objective: Precise prevention is more desired for cervical cancer due to the huge population, high prevalence of human papillomavirus(HPV) infection in China and the vision of screen-and-treat strategies in low-and middleincome countries(LMICs). Considerations of combining type-specific prevalence and attribution proportion to high-grade cervical intraepithelial neoplasia are informative to more precise and effective region-specific cervical cancer prevention and control programs. The aim of the current study was to determine the genotype distribution of HPV and attribution to cervical precancerous lesions among women from rural areas in North China.Methods: A total of 9,526 women participated in the cervical cancer screening project in rural China. The samples of women who tested positive for HPV were retested with a polymerase chain reaction(PCR)-based HPV genotyping test. The attribution proportion of specific high-risk human papillomavirus(HR-HPV) types for different grades of cervical lesions was calculated by using the type contribution weighting method.Results: A total of 22.2%(2,112/9,526) of women were HR-HPV positive and HPV52(21.7%) was the most common HR-HPV genotype, followed by HPV58(18.2%), HPV53(18.2%) and HPV16(16.2%). The top three genotypes detected in HR-HPV-positive cervical intraepithelial neoplasia(CIN)1 were HPV16(36.7%), HPV58(20.4%), HPV56(15.3%). Among CIN2+, the most frequent genotypes were HPV16(75.6%), HPV52(17.8%),HPV58(16.7%). HPV16, 56, 58, 53, 52, 59, 68, and 18 combined were attributed to 84.17% of all CIN1 lesions,and HPV16, 58, and 52 combined were attributed to 86.98% of all CIN2+ lesions.Conclusions: The prevalence of HR-HPV infection among women from rural areas in North China was high and HPV16, HPV58, HPV52 had paramount attributable fraction in CIN2+. Type-specific HPV prevalence and attribution proportion to cervical precancerous lesions should be taken into consideration in the development of vaccines and strategy for screening in this population. 展开更多
关键词 Human PAPILLOMAVIRUS CERVICAL intraepithelial NEOPLASIA GENOTYPE DISTRIBUTION ATTRIBUTION proportion CERVICAL cancer
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