检索结果-南通市图书馆

Numerical Study of Flow Features Around Submerged Circular and Square Piles at Flat and Scoured Beds Using OpenFOAM

Journal of Ocean University of China 2024年第4期23卷 897-914页

作者： WANG Chaolin WU Guoxiang WANG Dianhe DU Shengtao z.ANG z.iyong JIN Heng z.U david z. LIANG Bingchen Donghai Academy School of Civil&Environmental Engineering and Geography ScienceNingbo UniversityNingbo 315211China Key Laboratory of Estuary and Coast of z.ejiang Province and Zhejiang Institute of Hydraulics and EstuaryHangzhou 310020China Shandong Provincial Key Laboratory of Ocean Engineering and College of EngineeringOcean University of ChinaQingdao 266100China Shandong Water Conservancy Vocational College Rizhao 276826China School of Mechanical and Energy Engineering Ningbotech UniversityNingbo 315211China

Elucidating the flow features around piles in local scouring processes is crucial for studies of local scouring mechanisms and scour depth *** study details the flow turbulence characteristics of two submerged piles that are determined by solving the Navier-Stokes equations with the improved delayed detached eddy simulation *** model is verified by comparing experimental and numerical results for hydrodynamic parameters with the literature for both square-crossing piles(SCPs)and circular-crossing piles(CCPs).Original topographies of flat and scoured beds(i.e.,the initial and equilibrium scouring stages)are based on experimental results obtained by the authors in the present *** and CCP flow features in the scouring process are *** results indicate that during the scouring process,the time-averaged drag coefficient and root mean square(rms)of the lift coefficient increase linearly in the CCP test,while the rms of the lift coefficient in the SCP test decreases ***,the minimum pressure coefficient is always located in the upstream corners in the SCP case but moves from 72.5°to 79.5°when the scour hole is completely developed in the CCP *** flow behind the pile,which is generated by separated boundary layers above the top face of the pile,can reach the sand bed and turn the separated shear layers into patches of small vortices in the near-wake ***,the high shear stress z.nes are mainly at the scour edges under scoured-bed conditions.

关键词： flat bed scoured bed local scour OpenFOAM bed shear stress

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

Serum amylase as a novel prognostic marker of organophosphorus poisoning: a retrospective study

引用

Emergency and Critical Care Medicine 2024年第3期4卷 111-116页

作者： Guo X. chen z. Feng K. z.ng S. z.ang J. Ma z. Yuan C. School of Clinical Medicine Ningxia Medical University Ningxia Hui Yinchuan China Emergency Department General Hospital of Ningxia Medical University Ningxia Hui Autonomous Region Yinchuan China

Background: This study aims to explore the significance of serum amylase levels in patients with organophosphorus pesticide (OP) poisoning and to provide a new perspective for evaluating the severity and prognosis of OP poisoning. Methods: The clinical data of 67 patients with acute OP poisoning, who had been treated in the emergency department of the General Hospital of Ningxia Medical University between September 2020 and August 2022, were retrospectively analyz.d. Using Spearman rank correlation, serum amylase levels during admission and severity of poisoning correlated with discharge outcomes. Based on serum amylase levels, receiver operating characteristic curves were plotted to predict the severity and mortality of patients who experience organophosphate poisoning. The optimal threshold serum amylase level at admission was determined based on the maximum Youden index. Results: Using Spearman rank correlation analysis, serum amylase levels at admission positively correlated with the severity of poisoning and discharge outcomes, but the degree of correlation was weak (rs: 0.344; 0.264; P 194.1 U/L at admission was 15.944 (95% CI: 1.825–139.274). Conclusion: Serum amylase levels in patients with organophosphate poisoning correlate with the degree of poisoning and discharge outcomes. Higher serum amylase level was a risk factor for organophosphorus poisoning death. © Wolters Kluwer Health, Inc. All rights reserved.

关键词： Amylase Emergency department Organophosphorus pesticide poisoning Prognosis

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

TcPO2 changes are more pronounced than SpO2 changes during simulated altitude changes in a hypobaric oxygen chamber: a nonrandomiz.d controlled trial

引用

Emergency and Critical Care Medicine 2024年第3期4卷 105-110页

作者： Li Y. chen L. Fu z. Wang z. Sun S. Luan X. Ma D. Hu T. School of Nursing and Rehabilitation Shandong University Shandong Jinan China Department of Emergency and Critical Care Medicine Qilu Hospital of Shandong University Shandong Jinan China Department of Pulmonary and Critical Care Medicine Qilu Hospital of Shandong University Shandong Jinan China Emergency Management Center of State Grid Shandong Electric Power Company Shandong Jinan China School of Nursing and Rehabilitation Cheeloo College of Medicine University of Shandong Department of Infection Control Qilu Hospital of Shandong University Shandong Jinan China School of Mechanical Engineering Shandong University Key Laboratory of the Ministry of Education for Efficient and Clean Machinery Manufacturing National Experimental Teaching Demonstration Center for Mechanical Engineering Shandong Jinan China

Background: Hypoxia is a significant risk factor of hypertension. However, no studies have used transcutaneous tissue partial pressure of oxygen (TcPO2) and partial pressure of carbon dioxide (TcPCO2) monitors to measure the respective partial pressures in healthy individuals. Oxygen saturation (SpO2) is often used for traditional monitoring of vital signs. This study investigated the changes in TcPO2 and SpO2 values during rapid changes in altitude. The trial was registered at *** (registration no. NCT06076057). Methods: Healthy adult volunteers were instructed to sit vertically in a hypobaric oxygen chamber, which ascended from 0 m to 2500 m at a uniform speed within 10 min. The Danish Radiometer TCM4 was used to measure TcPO2 and TcPCO2 with the ventral side of the upper arm as the measurement site. The Shenz.en Kerokan P0D-1 W pulse oximeter was used to measure heart rate and SpO2, with values recorded once every 500 m. Results: Altogether, 49 healthy volunteers were recruited between March 2023 and August 2023. With increasing altitude, TcPO2 and SpO2 decreased significantly (P 500 m, statistical significance was identified between TcPO2 in both sexes (P < 0.05). Statistical significance in TcPCO2 and heart rate was observed at the different elevations (P < 0.05). Conclusion: In acutely changing low-pressure hypoxic environments, TcPO2 changed more dramatically than SpO2 © Wolters Kluwer Health, Inc. All rights reserved.

关键词： Altitude change Low-pressure oxygen chamber Transcutaneous oxygen saturation Transcutaneous partial pressure of oxygen

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

A multi-sensor appiproach to calving detection

引用

Information Processing in Agriculture 2024年第1期11卷 45-64页

作者： Anita z.Chang david L.Swain Mark G.Trotter Institute for Future Farming Systems School of HealthMedicaland Applied SciencesCentral Queensland UniversityRockhamptonQueensland 4700Australia

The advent of remote livestock monitoring systems provides numerous possibilities for improving on-farm productivity,efficiency,and *** potential application for these systems is for the detection of calving *** study describes the integration of data from multiple sensor sources,including accelerometers,global navigation satellite systems(GNsS),an accelerometer-derived rumination algorithm,a walk-over-weigh unit,and a weather station for parturition detection using a support vector machine *** best performing model utilised data from GNsS,the ruminating algorithm,and weather stations to achieve 98.6%accuracy,with 88.5%sensitivity and 100%*** topranking features of this model were primarily GNSS *** study provides an overview as to how various sensor systems could be integrated on-farm to maximise calving detection for improved production and welfare outcomes.

关键词： Accelerometer GNSS GPS Rumination Sensor WOW

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

Granger causal representation learning for groups of time series

引用

Science China(Information Sciences) 2024年第5期67卷 56-68页

作者： Ruichu CAI Yunjin WU Xiaokai HUANG Wei chen Tom z.J.FU z.ifeng HAO School of Computer Science Guangdong University of Technology Peng cheng Laboratory College of Science Shantou University

Discovering causality from multivariate time series is an important but challenging *** existing methods focus on estimating the Granger causal structures among multivariate time series,while ignoring the prior knowledge of these time series, e.g., the group of the time series. Focusing on discovering the Granger causal structures among groups of time series, we propose a Granger causal representation learning method to solve this problem. First, we use the multiset canonical correlation analysis method to learn the Granger causal representation of each group of time series. Then, we model the Granger causal relationships among the learned Granger causal representations using a recurrent neural network with temporal information. Finally, we formulate the above two stages into one unified optimiz.tion problem, which is efficiently solved using the augmented Lagrangian method. We conduct extensive experiments on synthetic and real-world datasets to validate the correctness and effectiveness of the proposed method.

关键词： Granger causal discovery Granger causal representation learning time series data recurrent neural network multiset canonical correlation analysis

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

引用

Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying Wang Shengling Si Hongli Li david Da Yong chen National Institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Si Chuan z.ong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressuriz.d liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment *** effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of *** affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were *** optimum conditions were found to be 120℃,10 min,and 3 cycles,***-MS/MS method was developed to obtain the optimal sensitivity specific to *** method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/*** ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent *** optimiz.d method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target ***,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to *** is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressuriz.d liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control

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

Rational design of AgGaS/z.S/z.S quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

引用

Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu z.z.Fu Y.Y.chen H.Q.Dai z.Hu W.L.z.ang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China z.ongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesiz. highly luminescent AgGaS/z.S/z.S quantum dots(QDs).In the first step,an inner z.S shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer z.S shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesiz.d AgGaS/z.S/z.S QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS ***,the effect of halogen ions in z. precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between z. cation diffusion and z.S shelling ***,the z.S shelling reaction was dominant when z.Cl_(2)was employed,while z. cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the z.S shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

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

Geometric prior guided hybrid deep neural network for facial beauty analysis

引用

CAAI Transactions on Intelligence Technology 2024年第2期9卷 467-480页

作者： Tianhao Peng Mu Li Fangmei chen Yong Xu david z.ang The School of Computer Science and Technology Guizhou UniversityGuiyangChina Department of Automation Moutai InstituteRenhuaiGuizhouChina The School of Computer Science and Technology Harbin Institute of TechnologyShenzhenShenzhenChina The Information and Communication Engineering Department Dalian Minzu UniversityDalianChina The School of Data Science The Chinese University of Hong KongShenzhenShenzhenChina

Facial beauty analysis is an important topic in human *** may be used as a guidance for face beautification applications such as cosmetic *** neural networks(DNNs)have recently been adopted for facial beauty analysis and have achieved remarkable ***,most existing DNN-based models regard facial beauty analysis as a normal classification *** ignore important prior knowledge in traditional machine learning models which illustrate the significant contribution of the geometric features in facial beauty *** be specific,landmarks of the whole face and facial organs are introduced to extract geometric features to make the *** by this,we introduce a novel dual-branch network for facial beauty analysis:one branch takes the Swin Transformer as the backbone to model the full face and global patterns,and another branch focuses on the masked facial organs with the residual network to model the local patterns of certain facial ***,the designed multi-scale feature fusion module can further facilitate our network to learn complementary semantic information between the two *** model optimisation,we propose a hybrid loss function,where especially geometric regulation is introduced by regressing the facial landmarks and it can force the extracted features to convey facial geometric *** performed on the SCUT-FBP5500 dataset and the SCUT-FBP dataset demonstrate that our model outperforms the state-of-the-art convolutional neural networks models,which proves the effectiveness of the proposed geometric regularisation and dual-branch structure with the hybrid *** the best of our knowledge,this is the first study to introduce a Vision Transformer into the facial beauty analysis task.

关键词： deep neural networks face analysis face biometrics image analysis

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

Effects of Maternal Death on Children Living in the Sagnarigu Municipality

引用

Open Journal of Obstetrics and Gynecology 2024年第3期14卷 334-347页

作者： david z. Kolbila Abdul-Raz.k Doat david S. Nigarim Wilfred Kwose Sylvanus Kampo Department of Obstetrics and Gynecology School of Medicine University for Development Studies Tamale Ghana Department of Nursing School of Nursing and Midwifery C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Anaesthesia and Intensive Care School of Medicine and Dentistry C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana

Introduction: The greatest effect of maternal mortality is renowned in children aged 2 - 5 months whose mothers had died. Children whose mothers died due to maternal complications were likely to record a higher mortality in infancy compared to children of surviving mothers. Motherless children mostly suffer a lot due to lack of day-to-day care, isolation, lack of motivation as well as economic cost associated with mother’s death. Thus, the purpose of this study was to ascertain the lives of children whose mothers passed away during childbirth at the Sagnarigu Municipality. Methods: This quantitative cross-sectional study was carried out at the Sagnarigu Municipal. The study recruited 297 respondents. To assess the effects of maternal death on the lives of children, families that experienced maternal death were assessed. The number of pregnancies experienced by the deceased woman, pregnancy-related complaints experienced, determinants of maternal death, number of children alive, and their standard of living were assessed with the aid of a structured questionnaire. Results: The data showed that negligence, illiteracy, poor road access, poverty, ignorance, delays in recogniz.ng the problem, delays in making appropriate decisions, delays in the health facility, delays in giving the appropriate treatments, and traditional beliefs were some of the factors that led to maternal death in the Sagnarigu Municipality. Conclusion: The study concluded that determinants of maternal death in the Sagnarigu Municipal included the following;negligence, illiteracy, poverty, and delays in recogniz.ng the problem. The study findings also demonstrated that the effects of maternal death on children are diverse and cut across different areas of a child’s life including livelihood sustenance, healthcare, education, and emotional and psychological development.

关键词： Maternal Death Effects Orphans Children Pregnancy Childbirth

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

Structural basis for polyuridine tract recognition by SARS-CoV-2 Nsp15

引用

Protein & Cell 2024年第7期15卷 547-552页

作者： Fumiaki Ito Hanjing Yang z.Hong z.ou Xiaojiang S.chen Molecular and Computational Biology Department of Biological SciencesUniversity of Southern CaliforniaLos AngelesCA 90089United States Department of Microbiology Immunology and Molecular GeneticsUniversity of CaliforniaLos AngelesCA 90095United States California NanoSystems Institute University of CaliforniaLos AngelesCA90095United States Genetic Molecular and Cellular Biology ProgramKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90089United States Norris Comprehensive Cancer Center University of Southern CaliforniaLos AngelesCA 90089United States Center of Excellence in NanoBiophysics University of Southern CaliforniaLos AngelesCA 90089United States

Dear Editor,Coronaviruses have evolved a wide array of tactics to evade host antiviral *** host cells detect invading foreign nucleic acids including viral genome and viral replication intermediates,they activate interferon(IFN)signaling via cytoplasmic pattern recognition receptors(Kang et al.,2002;Kato et al.,2006).Remarkable stealth activities exhibited by coronaviruses are facilitated by a series of non-structural proteins(Nsps),such as Nsp15(Deng and Baker,2018;Deng et al.,2019;Hackbart et al.,2020),which is a uridine-specific endoribonuclease that mediates evasion of host detection of viral double-stranded RNA(dsRNA)(Bhardwaj et al.,2004;Deng et al.,2017;Fraz.er et al.,2021;Ivanov et al.,2004).Nsp15 targets a polyuridine[poly(U)]tract on the coronavirus negative strand RNA(Hackbart et al.,2020).Nsp15 limits the abundance and length of poly(U)within the negative strand RNA 5ʹ-extension by trimming down the initially synthesiz.d poly(U)lead sequence to the optimal length that can suppress dsRNA formation but still serves as a template for poly(A)tail of the positive strand genome of the coronaviruses(Hofmann and Brian,1991).

关键词： p15 interferon template

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

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：