检索结果-南通市图书馆

An introductory review of swarm technology for spacecraft on-orbit servicing

International Journal of Mechanical System Dynamics 2024年第1期4卷 3-21页

作者： el Ghali Asri Zheng H.Zhu Department of Mechanical Engineering York UniversityTorontoOntarioCanada

This review paper presents a comprehensive evaluation and forward-looking perspective on the underexplored topic of servicing target objects using spacecraft *** targets can be known or unknown,cooperative or uncooperative,and pose significant challenges in modern space operations due to their inherent complexity and *** servicing space objects is vital for active debris removal and broader on-orbit servicing tasks such as satellite maintenance,repair,refueling,orbital assembly,and *** effort has been invested in the literature to explore the servicing of targets using a single *** its advantages and benefits,this paper expands the discussion to encompass a swarm approach to the *** review covers various single-spacecraft approaches and presents a critical examination of the existing,although limited,body of work dedicated to servicing orbital objects using multiple *** focus is also broadened to include some influential studies concerning the characterization,capture,and manipulation of physical objects by general multiagent systems,a subject with significant parallels to the core interest of this ***,this article also delves into the realm of simultaneous localization and mapping,highlighting its application within close-proximity operations in space,especially when dealing with unknown uncooperative *** attention is paid to the benefits that this field can receive from distributed multiagent ***,an exploration of the promising field of swarm robotics is presented,with an emphasis on its potential to revolutionize the servicing of orbital target ***,a survey of general research directly engaging swarms in the orbital context is *** review aims to bridge the knowledge gap and stimulate further research in the underexplored domain of servicing space targets with spacecraft swarms.

关键词： space robotics on-orbit servicing close-proximity operations guidance and navigation swarm robotics multiagent systems object capture and manipulation simultaneous localization and mapping

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

Eco-toxicity and health risk assessment of polycyclic aromatic hydrocarbons in surface sediments of Burullus Lake in Egypt

引用

China Geology 2024年第3期7卷 460-468页

作者： Hanan E Osman Mohamed H E el-Morsy Hazem T Abd el-Hamid Department of Biology Faculty of Applied ScienceUmm Al-Qura UniversityMecca 24382Saudi Arabia Deanship of Scientific Research Umm Al-Qura UniversityMakkah 24372Saudi Arabia National Institute of Oceanography and Fisheries(NIOF) Cairo 11865Egypt Botany and Microbiology Department Faculty of ScienceAl-Azhar UniversityCairo 11651Egypt

Polycyclic aromatic hydrocarbons(PAHs)are ubiquitous environmental contaminants of growing concern due to their potential ecological and human health *** study presents a comprehensive assessment of PAHs contamination in the surface sediments of Burullus Lake,a vital and second largest delta lake in *** aim was to evaluate the eco-toxicity and potential health risks associated with the presence of these *** seven sediment samples were collected from various drains in the southern part of Burullus *** extraction method was employed to extract PAHs(16PAHs)from the sediment ***,target compounds were located using *** results showed that samples contained PAHs levels ranging from 0.038×10^(-6)to 0.459×10^(-6),which is considered heavily polluted by the European standard for PAHs ***,there was no apparent source of PAHs in the elKhashah drain or the Brinbal Canal,as HPLC found none of the *** most prevalent compound in sediment samples along the study area was *** diagnostic indices in the present study indicated that the hydrocarbons in the region originated from pyrolytic and man-made sources along the drains of Burullus *** principal component analysis(PCA)and diagnostic ratios revealed that coal combustion and pyrolytic sources were responsible for the PAHs contamination in the surface *** non-carcinogenic risk(HI),which is the product of the HQs for the adult and child populations,respectively,was *** values under 1,therefore,demonstrated that they had no carcinogenic effects on human *** and MEQs in the sediments of Burullus Lake do not have a cancer-causing impact on *** the safety of nearby wildlife,aquatic life,and people,all activities that raise petroleum hydrocarbon levels in Burullus Lake must be adequately regulated and *** to the ecological risk assessment,there is little chance that PAHs will be found

关键词： Polycyclic aromatic hydrocarbons Diagnostic indices Toxicity Delta lake sediment Burullus Lake Human health risk Aquatic ecosystem HPLC Coal combustion

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

Rao Algorithms-Based Structure Optimization for Heterogeneous Wireless Sensor Networks

引用

Computers, Materials & Continua 2024年第1期78卷 873-897页

作者： Shereen K.Refaay Samia A.Ali Moumen T.el-Melegy Louai A.Maghrabi Hamdy H.el-Sayed Faculty of Computers and Artificial Intelligence Sohag UniversitySohag82524Egypt Faculty of Engineering Assiut UniversityAssiut711745Egypt College of Engineering University of Business and TechnologyJeddah23411Saudi Arabia

The structural optimization of wireless sensor networks is a critical issue because it impacts energy consumption and hence the network’s *** studies have been conducted for homogeneous networks,but few have been performed for heterogeneouswireless sensor *** paper utilizes Rao algorithms to optimize the structure of heterogeneous wireless sensor networks according to node locations and their initial *** proposed algorithms lack algorithm-specific parameters and metaphorical *** proposed algorithms examine the search space based on the relations of the population with the best,worst,and randomly assigned *** proposed algorithms can be evaluated using any routing protocol,however,we have chosen the well-known routing protocols in the literature:Low Energy Adaptive Clustering Hierarchy(LEACH),Power-Efficient Gathering in Sensor Information Systems(PEAGSIS),Partitioned-based Energy-efficient LEACH(PE-LEACH),and the Power-Efficient Gathering in Sensor Information Systems Neural Network(PEAGSIS-NN)recent routing *** compare our optimized method with the Jaya,the Particle Swarm Optimization-based Energy Efficient Clustering(PSO-EEC)protocol,and the hybrid Harmony Search Algorithm and PSO(HSA-PSO)*** efficiencies of our proposed algorithms are evaluated by conducting experiments in terms of the network lifetime(first dead node,half dead nodes,and last dead node),energy consumption,packets to cluster head,and packets to the base *** experimental results were compared with those obtained using the Jaya optimization *** proposed algorithms exhibited the best *** proposed approach successfully prolongs the network lifetime by 71% for the PEAGSIS protocol,51% for the LEACH protocol,10% for the PE-LEACH protocol,and 73% for the PEGSIS-NN protocol;Moreover,it enhances other criteria such as energy conservation,fitness convergence,packets to cluster head,and packets to the base sta

关键词： Wireless sensor networks Rao algorithms optimization LEACH PEAGSIS

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

Evolution of blockchain consensus algorithms: a review on the latest milestones of blockchain consensus algorithms

引用

Cybersecurity 2024年第3期7卷 80-101页

作者： Ziad Hussein May A.Salama Sahar A.el-Rahman electrical Engineering Department Faculty of Engineering-ShoubraBenha UniversityCairoEgypt

Blockchain technology has gained widespread adoption in recent years due to its ability to enable secure and trans-parent record-keeping and data transfer.A critical aspect of blockchain technology is the use of consensus algorithms,which allow distributed nodes in the network to agree on the state of the *** this review paper,we exam-ine various consensus algorithms that are used in blockchain systems,including proof-of-work,proof-of-stake,and hybrid *** go over the trade-offs and factors to think about when choosing a consensus algorithm,such as energy efficiency,decentralization,and *** also look at the strengths and weaknesses of each algorithm as well as their potential impact on the scalability and adoption of blockchain technology.

关键词： Blockchain Consensus Proof of work Proof of stake Decentralization

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

Genetic Variability and Phenotypic Correlations Study among Grain Quality Traits and Mineral elements Concentrations in Colored and Non-Colored Rice (Oryza sativa L.)

引用

Phyton-International Journal of Experimental Botany 2024年第7期93卷 1733-1748页

作者： Adel A.Rezk Mohamed M.el-Malky Heba I.Mohamed Hossam S.el-Beltagi Agricultural Biotechnology Department College of Agricultural and Food ScienceKing Faisal UniversityAl-Ahsa31982Saudi Arabia Plant Pathology Research Institute Agriculture Research CenterGiza12619Egypt Rice Research and Training Center Field Crop Research InstituteAgriculture Research Center33717Egypt Biological and Geological Sciences Department Faculty of EducationAin Shams UniversityCairo11511Egypt Biochemistry Department Faculty of AgricultureCairo UniversityGiza12613Egypt

Twenty-four rice genotypes were examined to assess genetic variability,heritability,and correlations for seven-grain quality traits,eight nutritional elements,and *** revealed signiﬁcant differences for the quality traits *** every trait under study,the phenotypic coefﬁcient of variation was higher than the correspon-dence genotypic coefﬁcient of *** in a broad sense varied from 29.75%for grain length to 98.31%for the elongation *** percentage recovery had a highly signiﬁcant positive correlation with milling and head rice ***,milling percentage had a highly positive correlation with head rice *** amylose percentage,all the genotypes belonged to low amylose except the Hassawi-1 variety,which had intermediate amylose *** nutrition contents of magnesium(Mg),sodium(Na),potas-sium(K),calcium(Ca),copper(Cu),manganese(Mn),zinc(Zn),iron(Fe),or protein percentage gave different variations for 24 rice genotypes under all the nutritional *** the 24 genotypes,ten rice genotypes–HighNutrient-1,HighNutrient-2,HighNutrient-9,HighNutrient-8,HighNutrient-3,Hassawi-2,HighNutrient-7,HighNutrient-6,Hassawi-1,and HighNutrient-4–had the highest heist value for all nutritional and protein con-tents,and could be used as a donor to improving new *** was a positive and signiﬁcant correlation between magnesium Mg,K,Zn and ***,K had a positive correlation with zinc Zn,Fe,and protein *** analysis was divided into two groups:theﬁrst group included all genotypes rich in nutri-ents,while the remaining genotypes with low nutritional content were included in the second group.

关键词： Amylose cluster analysis genotypes grain quality mineral nutrition rice

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

Performance Evaluation of an Evaporative Cooling Pad for Humidification-Dehumidification Desalination

引用

Fluid Dynamics & Materials Processing 2024年第10期20卷 2323-2335页

作者： Ibtissam el Aouni Hicham Labrim elhoussaine Ouabida Ahmed Ait Errouhi Rachid el Bouayadi Driss Zejli Aouatif Saad Advanced Systems Engineering Laboratory National School of Applied SciencesIbn Tofail UniversityKenitra14000Morocco

The perfect combination of renewable energy and desalination technologies is the key to meeting water demands in a cost-effective,efficient and environmentally friendly *** desalination technique by humidificationdehumidification is non-conventional approach suitable for areas with low infrastructure(such as rural and decentralized regions)since it does not require permanent *** this study,this technology is implemented by using solar energy as a source of thermal power.A seawater desalination unit is considered,which consists of a chamber with two evaporators(humidifiers),a wetted porous material made of a corrugated cellulose cardboard and a condenser(dehumidifier).The evaporation system is tested with dry bulb temperature and relative air humidity *** results of numerical simulations indicate that higher inlet air velocities(from 0.75 to 3 m/s)lead to a decrease in theΔT,ΔRH,and *** the air remaining within the evaporator for 30 cm,the temperature differential increases to 5.7°C,accompanied by a 39%rise in relative humidity *** changes result in a significant enhancement in humidification efficiency,achieving a remarkable efficiency level of 78%.However,a wettability value of 630 m^(2)/m^(3)leads to a smaller reduction of these *** the pad thickness,particularly to 0.3 m,improves performance by boostingΔT,ΔRH,and effectiveness,especially for pads with a wettability of 630 m^(2)/m^(3),for which superior performances are predicted by the numerical tests.

关键词： Desalination humidification dehumidification porous material solar energy evaporator

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

Mafic and felsic magmatism in the Wadi Kalalat area, South Eastern Desert, Egypt: mineralogy, geochemistry and geodynamic evolution during the Neoproterozoic in the Nubian Shield

引用

Acta Geochimica 2024年第1期43卷 150-173页

作者： Adel A.Surour Ahmed A.Madani Mohamed A.el-Sobky Faculty of Science Galala UniversityNew Galala CitySuez 43511Egypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Egyptian Mineral Resources Authority P.O.Box 11517AbbasiyaCairoEgypt

In the south Eastern Desert of Egypt,two contrasting types of magmatism(mafic and felsic) are recorded in the Wadi Kalalat area,and form the Gabal el Motaghiarat and Gabal Batuga intrusions,*** two intrusions post-dates ophiolitic and arc associations represented by serpentinite and metagabbro-diorite,*** mafic intrusion has a basal ultramafic member represented by fresh peridotite,which is followed upward by olivine gabbro and anorthositic or *** mafic intrusion pertains to the Alaskan-type mafic-ultramafic intrusions in the Arabian-Nubian Shield(ANS)being of tholeiitic nature and emplaced in a typical arc *** the other hand,the Gabal Batuga intrusion comprises three varieties of fresh A-type granites of high K-calc alkaline nature,which is peraluminous and garnetbearing in parts.A narrow thermal aureole in the olivine gabbro of the mafic intrusion was developed due to the intrusion of the Batuga *** results in the development of a hornfelsic melagabbro variety in which the composition changed from tholeiitic to a calc-alkaline composition due to the addition of S_(i)O_(2),Al_(2)O_(3),alkalis,lithosphile elements(LILEs) such as Rb(70 ppm) and Y(28 ppm) from the felsic *** the thermal aureole,Rb amounts 2-8 ppm and Y lies in the range elieved that the Gabal Batuga felsic intrusion started to emplace during the waning stage of an arc system,with transition from the pre-collisional(i.e.,arc setting) to post-collisional and within plate *** from which the Gabal Batuga granites were fractionated is high-K calc-alkaline giving rise to a typical post-collisional A-type granite(A_(2)-subtype) indicating an origin from an underplating crustal ***,it is stressed here that the younger granites in the ANS are not exclusively post-collisional and within-plate but most likely they started to develop before closure of the arc *** possible source(s) of mafic magmas

关键词： Wadi Kalalat Gabal el Motaghairat mafic intrusion Gabal Batuga felsic intrusion Arc setting Post-collision Within-plate

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

Immunobiodiversity:Conserved and specific immunity across land plants and beyond

引用

Molecular Plant 2024年第1期17卷 92-111页

作者： Baptiste Castel Karima el Mahboubi Christophe Jacquet Pierre-Marc Delaux Laboratoire de Recherche en Sciences Végétales(LRSV) Universitéde ToulouseCNRSUPSToulouse INPCastanet-TolosanFrance

Angiosperms represent most plants that humans cultivate,grow,and ***,angiosperms are only one of five major land plant *** a whole lineage,plants also include algal *** these clades represent a tremendous genetic diversity that can be investigated to reveal the evolutionary history of any given *** this review,we describe the current model of the plant immune system,discuss its evolution based on the recent literature,and propose future directions for the *** angiosperms,plant–microbe interactions have been intensively studied,revealing essential cell surface and intracellular immune receptors,as well as metabolic and hormonal defense *** diversity at the genomic and functional levels demonstrates the conservation of these pathways across land plants,some of which are beyond *** basis of the conserved mechanisms,lineage-specific variations have occurred,leading to diversified reservoirs of immune *** rare cases,this diversity has been harnessed and successfully transferred to other species by integration of wild immune receptors or engineering of novel forms of receptors for improved resistance to *** propose that exploring further the diversity of immune mechanisms in the whole plant lineage will reveal completely novel sources of resistance to be deployed in crops.

关键词： evolution MPMI immunity plant evoMPMI symbiosis

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

Enhancing sustainability in phosphate ore processing:Performance of frying oil as alternative flotation collector for carbonate removal

引用

International Journal of Mining Science and Technology 2024年第4期34卷 557-571页

作者： Asmae el-bahi Yassine Taha Yassine Ait-Khouia Abdellatif elghali Mostafa Benzaazoua Geology&Sustainable Mining Institute(GSMI) Mohammed VI Polytechnic UniversityBen Guerir 43150Morocco

Recycling waste frying oils for the synthesis of flotation reagents presents a promising avenue for sustainable waste ***,it offers a cost-effective solution for crafting a specialized collector designed to efficiently remove carbonates and enhance phosphate enrichment in froth flotation *** study focuses on the synthesis of an anionic collector using the saponification reaction of a frying oil sample,subsequently applied to the flotation of calcite and *** elucidate the adsorption mechanisms of the frying oil collector(FrOC)and sodium oleate,a reference collector,on fluorapatite,calcite,dolomite,and quartz surfaces,comprehensive experiments were conducted,including zeta potential measurements and Fourier transform infrared *** revealed diverse adsorption affinities of the molecules towards these *** assess the practical performance of the collector,flotation tests were conducted using a natural phosphate ore mixture,employing a BoxBehnken experimental ***,under optimized conditions(pH 9,1000 g/t of FrOC,3.5 min of conditioning,and 6 min of flotation),FrOC exhibited excellent performance,with calcite and dolomite recoveries exceeding 80%,while apatite recovery in the concentrate fraction remained below 10%.This work exemplifies both circular economy practices and the distinctive approach to sustainable mineral processing.

关键词： Frying oils recycling Phosphate beneficiation Flotation separation Green surfactants Sustainability

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

Hepatitis B virus as a risk factor for hepatocellular carcinoma: There is still much work to do

引用

Liver Research 2024年第2期8卷 83-90页

作者： Walaa Abdelhamed Mohamed el-Kassas Endemic Medicine Department Sohag University Sohag Egypt Endemic Medicine Department Faculty of Medicine Helwan University Cairo Egypt Liver Disease Research Center College of Medicine King Saud University Riyadh Saudi Arabia

Hepatitis B virus (HBV) infection is a significant health problem that can result in progression to liver cirrhosis, decompensation, and the development of hepatocellular carcinoma (HCC). On a country level, the prevalence of chronic HBV infection varies between 0.1% and 35.0%, depending on the locality and the population being investigated. One-third of all liver cancer fatalities worldwide are attributable to HBV. The adoption of standard birth-dose immunization exerted the most significant impact on the decline of HBV prevalence. HCC incidence ranges from 0.01% to 1.40% in noncirrhotic patients and from 0.9% to 5.4% annually, in the settings of liver cirrhosis. Although antiviral therapy significantly reduces the risk of developing HBV-related HCC, studies have demonstrated that the risk persists, and that HCC screening is still essential. This review discusses the complex relationship between HBV infection and HCC, recent epidemiological data, different aspects of clinical disease characteristics, and the impact of antiviral therapy in this context.

关键词： Hepatitis B virus (HBV) Hepatocellular carcinoma (HCC) HBV vaccine Carcinogenesis Antiviral therapy

来源：评论

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

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

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：