检索结果-南通市图书馆

Numerical simulation of self-similar thermal convection from a spinning cone in anisotropic porous medium

Journal of Hydrodynamics 2016年第2期28卷 184-194页

作者： O. anwar BEG m. J. UDDIN T. BEG R. Reddy GORLA Spray Research Group Petroleum and Gas Engineering Division Room G77 Newton Building School of Computing Science and Engineering (CSE) University of Salford M54WT UK Department of mathematics American International University-Bangladesh Dhaka Bangladesh Engineering mechanics Associates Dickenson Road Manchester M 16 England UK Department mechanical Engineering Cleveland State University Cleveland Ohio USA

Self-similar steady natural convection thermal boundary layer flow from a rotating vertical cone to anisotropic Darcian porous medium is investigated theoretically and numerically. The transformed non-dimensional two-point boundary value problem is reduced to a system of coupled, highly nonlinear ordinary differential equations, which are solved subject to robust surface and free stream boundary conditions with the mAPLE 17 numerical quadrature software. Validation with earlier non-rotating studies is included, and also further verification of rotating solutions is achieved with a variational finite element method （FEm）. The rotational （spin） parameter emerges as an inverse function of the Grashof number. The influence of this parameter, primary Darey number, secondary Darcy number and Prandtl number on tangential velocity and swirl velocity, temperature and heat transfer rate are studied in detail. It is found that the dimensionless tangential velocity increases whilst the dimensionless swirl velocity and temperature decrease with the swirl Darcy number, tangential Darcy number and the rotational parameters. The model finds applications in chemical engineering filtration processing, liquid coating and spinning cone distillation columns.

关键词： self-similarity spinning cone finite element method (FEm) anisotropic porous medium heat transfer mAPLE FEm

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cross Section of Heavy Ion Reaction （14.5 meV/u） ^132Xe ＋ Bi

引用

Chinese Physics Letters 2006年第3期23卷 572-575页

作者： G. Sher m.I. Shahzad m. Hussain m. A. rana E. U. Khan Physics Research Division PINSTECH P.O Nilore Islamabad Pakistan Department of Physics University of the Punjab Lahore Pakistan

We investigate the cross section of the heavy ion reaction （14.5 meV/u） ^132Xe ＋ Bi by using a CR-39 plastic track detector. The target-detector assembly is exposed at UNILAC beam facility of GSI, Germany. After etching under appropriate etching conditions, the detector is scanned for multipronged events produced as a result of interactions of projectile ions with target atoms. The elastic events are separated from binary events and used for the determination of the quarter-point angle. The quarter-point angle obtained is used to determine the total reaction cross section. The total experimental reaction cross section is determined by using statistics of inelastic events of two-pronged and higher multiplicity events. The experimental reaction cross sections determined by using elastic and inelastic data observed in the reaction under study are found to be in good agreement with the theoretically calculated value of reaction cross section using a sharp cutoff model.

关键词： SEQUENTIAL FISSION COULOmB BARRIER TRACK DETECTORS NUCLEAR SCATTERING PB-208

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Which are the most favourable conditions for reducing soil CO_(2)emissions with no-tillage?Results from a meta-analysis

引用

International Soil and Water Conservation Research 2022年第3期10卷 497-506页

作者： Simone Bregaglio Gabriele mongiano Rossana m.Ferrara Fabrizio Ginaldi Alessandra Lagomarsino Gianfranco rana CREA-Council for Agricultural Research and Economics Research Centre for Agriculture and EnvironmentI-40128BolognaItaly CREA-Council for Agricultural Research and Economics Research Centre for Plant Protection and CertificationSS 11 km 2500I-13100VercelliItaly CREA-Council for Agricultural Research and Economics Research Centre for Agriculture and EnvironmentI-70125BariItaly CREA-Council for Agricultural Research and Economics Research Centre for Agriculture and EnvironmentI-50125FirenzeItaly

No-tillage practices have a recognised beneficial impact on soil and water conservation while reducing erosion processes and enhancing soil organic matter ***,scientists continue to debate the effectiveness of no-tillage in reducing soil carbon dioxide(CO_(2))emissions from *** the same line of inquiry pursued by the authors who reviewed the impact of conservative practices on direct CO_(2)emissions,we applied meta-analytic and machine learning techniques to unravel the effect of no-tillage under contrasting pedo-environmental conditions and agricultural *** analysed fifty-six experimental studies investigating direct soil CO_(2)emissions from no-tillage and conventional tillage practices(102 paired observations),considering pedological(soil texture,soil organic carbon content),environmental(climate type),and management(crop rotation,experiment duration)*** estimated the effect of different practices on the daily amount of soil CO_(2)emissions,and the impact of tillage in the period immediately following the *** main insights of this study are:(i)the conditions leading to the highest reduction of CO_(2)emissions due to no-tillage were long-term experiments(standardised mean differenceβ=0.64)conducted in arid environments(β=0.76)and clay soils(β=0.81),with low organic carbon content(β=0.79)where crop rotations(β=0.65)were performed;(ii)the same conditions were associated with the lowest absolute CO_(2)emissions,irrespective of soil management;(iii)the highest contribution to the variability of absolute soil CO_(2)emissions was associated with soil texture(mean decrease in accuracy of Random Forest models,mDA=4.57),rotation(mDA=3.07),experiment duration(mDA=2.93)and soil organic carbon content(mDA=2.24),rather than to tillage practices;(iv)soil CO_(2)emissions almost doubled in the first day after a tillage event,consistently across studies(p=0.001).This meta-analysis offers quantitative figures on the impact of tillage

关键词： Agricultural soils Greenhouse gases Global warming Net-zero agriculture

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ranked-Set Sampling Based Distribution Free Control Chart with Application in CSTR Process

引用

Computer modeling in Engineering & Sciences 2023年第6期135卷 2091-2118页

作者： Ibrahim m.Almanjahie Zahid Rasheed majid Khan Syed masroor anwar Ammara Nawaz Cheema Department of mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia School of mathematics and Statistics Xi’an Jiaotong University ChinaXi’an710049China Department of mathematics Women University of Azad Jammu and KashmirBagh12500Pakistan Government Post Graduate College Haripur22620Pakistan Department of Statistics University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of mathematics Air UniversityIslamabad44000Pakistan

Nonparametric(distribution-free)control charts have been introduced in recent years when quality characteristics do not follow a specific *** the sample selection is prohibitively expensive,we prefer ranked-set sampling over simple random sampling because ranked set sampling-based control charts outperform simple random sampling-based control *** this study,we proposed a nonparametric homogeneously weighted moving average based on theWilcoxon signed-rank test with ranked set sampling(NPHWmARSS)control chart for detecting shifts in the process location of a continuous and symmetric *** Carlo simulations are used to obtain the run length characteristics to evaluate the performance of the proposed NPHWmARSS control *** proposed NPHWmARSS control chart’s performance is compared to that of parametric and nonparametric control *** control charts include the exponentially weighted moving average(EWmA)control chart,Wilcoxon signed-rank with simple random sampling based the nonparametric EWmA control chart,the nonparametric EWmA sign control chart,Wilcoxon signed-rank with ranked set sampling-based the nonparametric EWmA control chart,and the homogeneously weighted moving average control *** findings show that the proposed NPHWmARSS control chart performs better than its competitors,particularly for the small ***,an example is presented to demonstrate how the proposed scheme can be implemented practically.

关键词： Nonparametric control charts run-length ranked set sampling Wilcoxon signed-rank

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Spanning Simplicial Complexes of Uni-Cyclic Graphs

引用

Algebra Colloquium 2015年第4期22卷 707-710页

作者： Imran anwar Zahid Raza Agha Kashif COmSATS Institute of Information Technology Lahore Pakistan National University of Computer and Emerging Sciences Lahore Campus Pakistan National University of Computer and Emerging Sciences Lahore Campus Pakistan Department of Mathematics University of Management and Technology

In this paper, we introduce the concept of the spanning simplicial complex As（G） associated to a simple finite connected graph G. We characterize all spanning trees of the uni-cyclic graph Un,m. In particular, we give a formula for computing the Hilbert series and h-vector of the Stanley-Reisner ring k[△s（Un,m）]. Finally, we prove that the spanning simplicial complex △s（Un,m） is shifted and hence is shellable.

关键词： primary decomposition Hilbert series f-vector h-vector spanning tree

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optimization and comparison of two different 3D culture methods to prepare cell aggregates as a bioink for organ printing

引用

BIOCELL 2012年第1期36卷 37-45页

作者： rana ImANI SHAHRIAR HOJJATI EmAmI HOSSEIN FAKHRZADEH NAFISEH BAHEIRAEI ALI m SHARIFI Department of Biomedical Engineering Amirkabir University of TechnologyTehranIran Endocrinology and metabolism Research Institute Tehran University of Medical SciencesTehranIran Razi Institute for Drug research Department of PharmacologySchool of MedicineTehran University of Medical SciencesTehranIran Department of Tissue Engineering and Cell therapy School of advanced sciences in MedicineTehran University of Medical Sciences.TehranIran

The ultimate goal of tissue engineering is to design and fabricate functional human tissues that are similar to natural cells and are capable of *** of cell aggregates is one of the important steps in 3D tissue engineering technology,particularly in organ *** simple methods,hanging drop(HD)and conical tube(CT)were utilized to prepare cell *** size and viability of the aggregates obtained at different initial cell densities and pre-culture duration were *** proliferative ability of the cell aggregates and their ability to spread in culture plates were also *** both methods,the optimum average size of the aggregates was less than 500μ*** aggregates were smaller than HD aggregates.5,000 cells per drop HD aggregates showed a marked ability to attach and spread on the culture *** proliferative ability reduced when the initial cell density was *** these methods,we found that the HD method having better size controlling ability as well as enhanced ability to maintain higher rates of viability,spreading,and *** conclusion,smaller HD aggregates might be a suitable choice as building blocks for making bioink particles in bioprinting technique.

关键词： tissue engineering hanging drop conical tube bioprinting

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Gallbladder carcinoma in a pregnant patient with Crohn's disease complicated with gallbladder involvement

引用

World Journal of Gastrointestinal Oncology 2013年第2期5卷 29-33页

作者： Shada Attraplsi Rima m Shobar Ihab Lamzabi rana Abraham Graduate College Rush University Department of Pathology Rush University Department of Gastroenterology and Nutrition Rush University

Primary gallbladder (GB) carcinoma and Crohn's disease (CD) of the GB are individually rare. We present a case of a pregnant woman with CD found to have GB involvement and primary GB carcinoma. A 34-year-old female at 6 wk gestation with a 21 year history of CD of uncertain extent presented with 3 mo of diarrhea, urgency and abdominal pain. During work-up, she was found to have elevated transaminases and an abnormal alkaline phosphatase. Imaging revealed two gallbladder polyps both greater than 1 cm in size. Resection and histological evaluation was consistent with Crohn's involvement of the GB, poorly differentiated adenocarcinoma of the GB with invasion through the muscularis propria and matted lymph nodes in the porta hepatis positive for metastatic carcinoma (stage pT2N1). Six cases of CD involving the GB, two cases of primary GB carcinoma in CD, and ten cases of cholangiocarcinoma in pregnancy have been *** is the only case that describes all three factors. Common features in CD of the GB include acute cholecystitis, ileal involvement, and presence independent of active intestinal disease. Common features in CD patients with GB malignancy include younger age of detection, a long history of CD, extensive colonic and ileal involvement of disease, the absence of cholelithiasis, and pre-existing gallbladder disease (primary sclerosing cholangitis and gallbladder polyps). Pregnancy is specific to this case. The role of CD in the development of GB malignancy is not well understood nor is the contribution of pregnancy to the spread of disease. Chronic inflammation and immunosuppression compounded by hormonal influence is implicated.

关键词： Crohn’s disease Cholangiocarcinoma Gallbladder Gallbladder carcinoma Inflammatory bowel disease

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plant endemism in the Nepal Himalayas and phytogeographical implications

引用

Plant Diversity 2019年第3期41卷 174-182页

作者： Achyut Tiwari Yadav Uprety Santosh Kumar rana Department of Botany Tri-Chandra Campus Tribhuvan University Kathmandu Nepal Central Department of Botany Tribhuvan University Kirtipur Kathmandu Nepal Research Centre for Applied Science and Technology Tribhuvan University Kathmandu Nepal IUCN (International Union for Conservation of Nature) Kathmandu Nepal Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 Yunnan China University of Chinese Academy of Sciences Beijing 100049 China

Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this l

关键词： Himalaya Topography Endemism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Clear felling and burning effects on soil nitrogen transforming bacteria and actinomycetes population in Chittagong University campus, Bangladesh

引用

Journal of Forestry Research 2012年第1期23卷 123-130页

作者： S.m. Sirajul Haque Rahima Ferdoshi Sohag miah m. Nural anwar Institute of Forestry and Environmental Sciences University of Chittagong Chittagong-4331 Bangladesh Department of microbiology University of Chittagong Chittagong-4331 Bangladesh

The effect of forests clear felling and associated burning on the population of soil nitrogen transforming bacteria and actinomycetes are reported at three pair sites of Chittagong University campus, Bangla- desh in monsoon tropical climate. Clear felled area or burnt site and 15-21 year mixed plantation of native and exotic species, situated side by side on low hill having Typic Dystrochrepts soil was represented at each pair site. At all the three pair sites, clear felled area or burnt site showed very significantly （p~_0.001） lower population of actinomycetes, Rhizobium, Nitrosomonas, Nitrobacter and ammonifying as well as deni- trifying bacteria compared to their adjacent mixed plantation. From en- vironmental consideration, this finding has implication in managing natural ecosystem.

关键词： Nitrogen transforming bacteria actinomycetes forest clearfelling effects burning effects soil microorganisms Chittagong HillTracts

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Capacity maximizing in massive mImO with linear precoding for SSF and LSF channel with perfect CSI

引用

Digital Communications and Networks 2021年第1期7卷 92-99页

作者： Tasher Ali Sheikh Joyatri Bora md.anwar Hussain Department of Electronics and Communication Engineering Nordi Eastern Regional Institute of Science and TechnologyNirjuliArunachal Pradesh791109India

The capacity of a massive mImO cellular network depends on user and antenna selection algorithms,and also on the acquisition of perfect Channel State Information(CSD).Low computational cost algorithms for user and an-tenna selection significantly may enhance the system capacity,as it would consume a smaller bandwidth out of the total bandwidth for downlink *** objective of this paper is to maximize the system sum-rate capacity with efficient user and antenna selection algorithms and linear *** consider in this paper,a slowly fading Rayleigh channel with perfect acquisition of CSI to explore the system sum-rate capacity of *** mImO *** user selection,we apply three algorithms,namely Semi orthogonal user selection(SUS),Descending Order of SNR-based User Scheduling(DOSUS),and Random User Selection(RUS)*** all the user selection algorithms,the selection of Base Station(BS)antenna is based on the maximum Signal-to-Noise Ratio(SNR)to the selected *** users are characterized by having both Small Scale Fading(SSF)due to slowly fading Rayleigh channel and *** Fading(ISF)due to distances from the base ***,we use linear precoding techniques,such as Zero Forcing(ZF),minimum mean Square Error(mmSE),.and maximum Ratio Transmission(mRT)to reduce interferences,thereby improving average system sum-rate *** using SUS,DOSUS,and RUS user selection algorithms with ZF,mmSE,and mRT precoding techniques are *** also analyzed and compared the computational complexity of all the three user selection *** computational complexities of the three algorithms that we achieved in this paper are 0(1)for RUS and DOSUS,and 0(m^2N)for suS which are less than the other conventional user selection methods.

关键词： massive mImO User selection Antenna selection Complexity DOSUS and antenna selection 5G

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：