检索结果-南通市图书馆

An approach of the internal friction-dependent temperature changes for conventional and pure biogenic lubricating greases

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第4期12卷 780-795页

作者： Leif AHME Erik KUHN miguelÁngel DELGAdo Department of Mechanical Engineering and Production Management Hamburg University of Applied SciencesHamburg 20099Germany Department of Chemical Engineering Research in Product Technology and Chemical Processes(Pro2TecS)University of HuelvaHuelva 21071Spain

This work investigated the temperature changes inside the bulk of lubricating greases under controlled high-shear stress conditions(250-500 s-1).For this purpose,a newly developed temperature-measuring cell called Calidus was successfully *** temperature changes(ΔT)have been related to the greases'components(thickener,base oil-type,and composition)and the structural degradation of the lubricating ***,a theoretical approach was proposed for calculating the internal temperature change of lubricating greases during shear *** greases showed an internal temperature profile characterised by a sudden rise inΔT within the first 4 h from starting the test and subsequentΔT decay until it reaches the steady state ***,it was found that greases C1 and C5,formulated with lithium and calcium soap,respectively,with different soap content(16.1 wt%and 9.7 wt%,respectively),but the same base castor oil,showed the highest value of the maximumΔT,c.a.3.2 K,and the most drastic drop ofΔ*** greases showed both the highest specific densities and heat *** addition,they showed the lowest ratio of expended energies(Rtee),which means more structural degradation in the stressed *** the contrary,the grease C3,with 13 wt%of Li-soap but the lowest base oil's viscosity,showed the lowest maximumΔT and the temperature profile was characterised by a moderate variation ofΔT along the *** biogenic grease B3 developed a low-temperature change in the group of pure bio-genic greases close to grease C3.

关键词： shear-induced structural degradation rheology temperature measurements lubricating greases density lubricating greases specific heat capacities

Random vibration analysis of FGM plates subjected to moving load using a refined stochastic finite element method

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

Defence Technology（防务技术） 2024年第4期34卷 42-56页

作者： Ngoc-Tu do Trung Thanh Tran Faculty of Mechanical Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The article introduces a finite element procedure using the bilinear quadrilateral element or four-node rectangular element(namely Q4 element) based on a refined first-order shear deformation theory(rFSDT) and Monte Carlo simulation(MCS), so-called refined stochastic finite element method to investigate the random vibration of functionally graded material(FGM) plates subjected to the moving *** advantage of the proposed method is to use r-FSDT to improve the accuracy of classical FSDT, satisfy the stress-free condition at the plate boundaries, and combine with MCS to analyze the vibration of the FGM plate when the parameter inputs are random quantities following a normal distribution. The obtained results show that the distribution characteristics of the vibration response of the FGM plate depend on the standard deviation of the input parameters and the velocity of the moving ***, the numerical results in this study are expected to contribute to improving the understanding of FGM plates subjected to moving loads with uncertain input parameters.

关键词： FGM Moving load R-FSDT Q4 element Monte Carlo simulation Random vibration

Endotoxin-induced alterations of adipose tissue function:a pathway to bovine metabolic stress

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2024年第4期15卷 1391-1407页

作者： miguel Chirivi G.Andres Contreras Department of Large Animal Clinical Sciences Michigan State UniversityEast LansingMIUSA

During the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expenditure puts cows in a state of metabolic stress characterized by excessive lipolysis in white adipose tissues(AT), increased production of reactive oxygen species, and immune cell dysfunction. Metabolic stress, especially in AT, increases the risk for metabolic and inflammatory diseases. Around parturition, cows are also susceptible to endotoxemia. Bacterial-derived toxins cause endotoxemia by promoting inflammatory processes and immune cell infiltration in different organs and systems while impacting metabolic function by altering lipolysis, mitochondrial activity, and insulin sensitivity. In dairy cows, endotoxins enter the bloodstream after overcoming the defense mechanisms of the epithelial barriers, particularly during common periparturient conditions such as mastitis, metritis, and pneumonia, or after abrupt changes in the gut microbiome. In the bovine AT, endotoxins induce a pro-inflammatory response and stimulate lipolysis in AT, leading to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signaling pathways and lipid synthesis. Endotoxin exposure can also induce oxidative stress in AT through the production of reactive oxygen species by inflammatory cells and other cellular components. This review provides insights into endotoxins' impact on AT function, highlighting the gaps in our knowledge of the mechanisms underlying AT dysfunction, its connection with periparturient cows' disease risk, and the need to develop effective interventions to prevent and treat endotoxemia-related inflammatory conditions in dairy cattle.

关键词： Adipose tissue dysfunction Endotoxin Inflammation Insulin resistance

Tau's function and dysfunction in the brain:when small changes have big consequences

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第1期19卷 152-153页

作者： miguel Portillo Debra Toiber Department of Life Sciences Ben-Gurion University of the NegevBeer ShevaIsraelThe Zlotowski Center for NeuroscienceBen-Gurion University of the NegevBeer ShevaIsrael

With the increase of life expectancy and population growth,neurodegenerative diseases have risen too and are projected to be a major health public concern by *** diseases are characterized by the progressive decline of cognitive function leading to the subsequent loss of *** the underlying causes of neurodegeneration are not well understood,aging is the main risk factor.

关键词： diseases consequences function

Velocity equation for grenades while impacting on dry sand media

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第5期35卷 168-173页

作者： Martin Macko Xuan Son Bui Kongsathit Phanthavong Duc Hung Pham Van Gion do Van Minh do Jiri Skala University of Defence BrnoCzech Republic Le Quy don Technical University Ha NoiViet Nam

This paper deals with the collision of sphere shape grenades with sand *** central issue of the article is the establishing of an empirical velocity equation of the grenade while impacting on sand that is used to solve motion equations of the mechanical mechanism inside the impact grenade *** paper focuses on impact velocities that are lower than 5 m s^(-1).An experiment was conducted to study the velocity of the grenade while impacting on dry sand.A high-speed camera video was used to capture the grenade *** grenade velocity in the impact process was generated from these video *** types of fitting curves are used to regress the velocity equation of the grenade while interacting with the sand media and the best-fitting model is *** result shows the regression curve has a high correlation with the experiment data for grenade velocities below 5 m s^(-1).The received regression equation is useful for analyzing the working ability of the inertial mechanism inside the impact grenade or analyzing and choosing the appropriate parameters of each part in the inertial mechanism to meet the required characteristics of the mechanism.

关键词： Dynamic response Impact velocity Impact grenade Low-velocity impact

A New Framework for Software Vulnerability Detection Based on an Advanced Computing

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第6期79卷 3699-3723页

作者： Bui Van Cong Cho do Xuan Department of Information Technology University of Economics and Technical IndustriesHanoi100000Vietnam Faculty of Information Security Posts and Telecommunications Institute of TechnologyHanoi100000Vietnam

The detection of software vulnerabilities written in C and C++languages takes a lot of attention and interest *** paper proposes a new framework called DrCSE to improve software vulnerability *** uses an intelligent computation technique based on the combination of two methods:Rebalancing data and representation learning to analyze and evaluate the code property graph(CPG)of the source code for detecting abnormal behavior of software *** do that,DrCSE performs a combination of 3 main processing techniques:(i)building the source code feature profiles,(ii)rebalancing data,and(iii)contrastive *** which,the method(i)extracts the source code’s features based on the vertices and edges of the *** method of rebalancing data has the function of supporting the training process by balancing the experimental ***,contrastive learning techniques learn the important features of the source code by finding and pulling similar ones together while pushing the outliers *** experiment part of this paper demonstrates the superiority of the DrCSE Framework for detecting source code security vulnerabilities using the Verum *** a result,the method proposed in the article has brought a pretty good performance in all metrics,especially the Precision and Recall scores of 39.35%and 69.07%,respectively,proving the efficiency of the DrCSE *** performs better than other approaches,with a 5%boost in Precision and a 5%boost in ***,this is considered the best research result for the software vulnerability detection problem using the Verum dataset according to our survey to date.

关键词： Source code vulnerability source code vulnerability detection code property graph feature profile contrastive learning data rebalancing

Biomaterials and emerging technologies for tissue engineering and in vitro models

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

Bio-Design and Manufacturing 2024年第3期7卷 237-239页

作者： J.miguel Oliveira Rui L.Reis 3B’s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT Government Associate Laboratory 4806-909 Braga/GuimarãesPortugal

The latest advances in the field of biomaterials have opened new avenues for scientific breakthroughs in tissue engineer-ing which greatly contributed for the successful translation of tissue engineering products into the market/***-materials are easily processed to become similar to natural extracellular matrix,making them ideal temporary supports for mimicking the three-dimensional(3D)microenvironment required for maintaining the adequate cell/tissue functions both in vitro and in vivo^([1]).

关键词： breakthrough biomaterials engineer

Integrated strategies on cobalt phosphides-based electrocatalysts for efficient hydrogen evolution reaction

在线全文

学校读者我要写书评

暂无评论

Tungsten 2024年第3期6卷 488-503页

作者： Thanh Dam Mai Ha Huu do Faculty of Mechanical Engineering and Technology Ho Chi Minh City University of Industry and Trade VKTech Research Center NTT Hi-Tech Institute Nguyen Tat Thanh University

The development of cost-effective and durable hydrogen evolution reaction(HER) electrocatalysts plays a vital role in dealing with the issues related to carbon dioxide *** phosphide-based nanomaterials are evaluated as promising advocates for HER due to high catalytic activities,good stability,and rich *** review commences with an exploration of the synthetic pathways of CoP,including solid-phase,solution-phase along with electrochemical ***,the mechanism of hydrogen formation is expressed thoroughly,after which various integrated strategies of morphology engineering with doping,assisted highly conductive materials,and construction of heterostructure were introduced for ***,burdensome tasks and possible guidance for the advancement of CoP-based nanomaterials were discussed for hydrogen production.

关键词： Cobalt phosphides Nanomaterials Electrocatalysts Hydrogen evolution reaction

Task Offloading in Edge Computing Using GNNs and DQN

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第6期139卷 2649-2671页

作者： Asier Garmendia-Orbegozo Jose David Nunez-Gonzalez miguel Angel Anton Department of Applied Mathematics University of the Basque Country UPV/EHUEibar20600Spain TECNALIA Basque Research and Technology Alliance(BRTA)San Sebastian20009Spain

In a network environment composed of different types of computing centers that can be divided into different layers(clod,edge layer,and others),the interconnection between them offers the possibility of peer-to-peer task *** many resource-constrained devices,the computation of many types of tasks is not feasible because they cannot support such computations as they do not have enough available memory and processing *** this scenario,it is worth considering transferring these tasks to resource-rich platforms,such as Edge Data Centers or remote cloud *** different reasons,it is more exciting and appropriate to download various tasks to specific download destinations depending on the properties and state of the environment and the nature of the *** the same time,establishing an optimal offloading policy,which ensures that all tasks are executed within the required latency and avoids excessive workload on specific computing centers is not *** study presents two alternatives to solve the offloading decision paradigm by introducing two well-known algorithms,Graph Neural Networks(GNN)and Deep Q-Network(DQN).It applies the alternatives on a well-known Edge Computing simulator called PureEdgeSimand compares them with the two defaultmethods,Trade-Off and Round *** showed that variants offer a slight improvement in task success rate and workload *** terms of energy efficiency,they provided similar ***,the success rates of different computing centers are tested,and the lack of capacity of remote cloud servers to respond to applications in real-time is *** novel ways of finding a download strategy in a local networking environment are unique as they emulate the state and structure of the environment innovatively,considering the quality of its connections and constant *** download score defined in this research is a crucial feature for determining the quality of a download path

关键词： Edge computing edge offloading fog computing task offloading