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Biomechanical Analysis of Implant Assisted-Overdentures with Variations in the Attachments systems

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Materials sciences and Applications 2015年第8期6卷 734-742页

作者： Eduardo Vedovatto Jose Vitor Quinelli Mazaro Humberto Gennari Filho Paulo sérgio Perri de Carvalho Caroline Cantieri de Mello Cleidiel Aparecido Araujo Lemos s&atilde o Leopoldo MandicInstituteandResearch Center Campinas Brazil department of Prosthodontic and dental Materials Ara&ccedil atuba school of dentistry S&atilde o Paulo state University (UNEsP) Ara&ccedil atuba Brazil department of surgery an Integrated Clinic Ara&ccedil atuba school of dentistry S&atilde o Paulo state University (UNEsP) Ara&ccedil atuba Brazil departmentof dental Materials and Prosthodontics Ara&ccedil atuba schoolofdentistry S&atilde o Paulo stateUniversity (UNEsP) Ara&ccedil atuba Brazil.

The aim of this study was to assess the stress patterns on the peri-implant zone and residual alveolar ridge in different overdenture attachment system designs by the photoelasticity method. Four attachments systems were tested: O-ring, ERA, Bar-clip, and Bar-clip/O-ring association. The prostheses were loaded with 100 N in five pre-determined points and the photoelastic model was evaluated by a circular polariscope. The anterior load, O-ring, and ERA showed better stress distribution in relation to the bars systems, which presented stress levels surrounding implants. The molar load, Bar-clip/O-ring association, presented the biggest stress concentration on the peri-implant region in relation to the others. When the second molar was loaded, there was a concentration of stress in the alveolar ridge in all situations analyzed. Within the limitation of this “in vitro” study, it could be concluded that there were biomechanical differences among the attachments systems analyzed, principally between isolated and the bars systems. The O-ring showed better stress distribution and the Bar-clip/O-ring showed higher stress concentration.

关键词： dental Implants Complete denture Overdentures

detection of Chlorophenolic Compounds in Bleaching Effluents of Chemical Pulps

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中国造纸 2008年第5期27卷 35-40页

作者： Chhaya sharma s. Mohanty s. Kumar N.J. Rao department of Paper Technology IIT-Roorkee India Gas Authority of India Ltd. Calcutta India JP Institute Gunna India

Laboratory bleaching effluents from the chlorination and caustic extraction stages of mixed wood kraft pulp processing have been analysed both qualitatively and quantitatively for various chlorophenolics by using GC.A number of chlorinated derivaties of phenols,catechols,guaiacols and syringaldehydes have been detected and their concentrations are *** results are compared with that of different agriculture residue/hardwood pulps,which were reported in *** concentrations of various compounds detected have also been compared with their reported 96LC50 values.

关键词：化学纸浆漂白方法制造方法造纸技术

Hybrid Authentication Using Node Trustworthy to detect Vulnerable Nodes

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Computer systems science & Engineering 2023年第4期45卷 625-640页

作者： s.M.Udhaya sankar s.Thanga Revathi R.Thiagarajan department of Information Technology Velammal Insitutue of TechnologyChennai601204India department of Networking and Communication SRM Institute of Science and TechnologyKattankulathur603203India department of Information Technology Prathyusha Engineering CollegeThiruvallur602025India

An ad-hoc sensor network(AsN)is a group of sensing nodes that transmit data over a wireless link to a target node,direct or indirect,through a series of *** becomes a high-risk group for several security exploits due to the sensor node’s limited *** threats are more challenging to protect against than external *** nodes are grouped,and calculate each node’s trust *** trust level is the result of combining internal and external trust *** heads(CH)are chosen based on the anticipated trust *** communications are then digitally signed by the source,encoded using a key pair given by a trustworthy CH,decoded by the recipient,and supervised by *** authenticates the technique by identifying the presence of both the transmitter and the *** approach looks for a trustworthy neighboring node that meets the trust threshold condition to authenticate the key *** companion node reaffirms the node’s reliability by getting the public-key *** seeking sensor node and the certification issuer node must have a close and trusting *** results of the proposed hybrid authentication using a node trustworthy(HANT)system are modeled and tested,and the suggested approach outperforms conventional trust-based approaches in throughput,latency,lifetime,and vulnerability methods.

关键词： Ad hoc sensor network wireless security clustering cryptography key management

Effect of viscous dissipation and heat source on flow and heat transfer of dusty fluid over unsteady stretching sheet

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Applied Mathematics and Mechanics(English Edition) 2012年第8期33卷 1001-1014页

作者： B.J.GIREEsHA G.s.ROOPA C.s.BAGEWADI department of studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451KarnatakaIndia

This paper investigates the problem of hydrodynamic boundary layer flow and heat transfer of a dusty fluid over an unsteady stretching surface. The study considers the effects of frictional heating （viscous dissipation） and internal heat generation or ab- sorption. The basic equations governing the flow and heat transfer are reduced to a set of non-linear ordinary differential equations by applying suitable similarity transformations. The transformed equations are numerically solved by the Runge-Kutta-Fehlberg-45 order method. An analysis is carried out for two different cases of heating processes, namely, variable wall temperature （VWT） and variable heat flux （VHF）. The effects of various physical parameters such as the magnetic parameter, the fluid-particle interaction pa- rameter, the unsteady parameter, the Prandtl number, the Eckert number, the number density of dust particles, and the heat source/sink parameter on velocity and temperature profiles are shown in several plots. The effects of the wall temperature gradient function and the wall temperature function are tabulated and discussed.

关键词： heat transfer boundary layer flow stretching surface dusty fluid viscousdissipation non-uniform heat source numerical solution

s-fuzzy Version of stone's Theorem for Distributive Lattices

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模糊系统与数学 2011年第4期25卷 47-54页

作者： Y.s.Pawar s.s.Khopade department of Mathematics Shivaji University

In this paper,we initiate a study of s-fuzzy ideal(filter) of a lattice where s stands for a meet semilattice.A s-fuzzy prime ideal(filter) of a lattice is defined and it is proved that a s-fuzzy ideal(filter) of a lattice is s-fuzzy prime ideal(filter) if and only if any non-empty α-cut of it is a prime ideal(filter).stone's theorem for a distributive lattice is extended by considering s-fuzzy ideals(filters).

关键词： Distributive Lattice semilattice Fuzzy Ideal Fuzzy Filter Prime Fuzzy Ideal Prime Fuzzy Filter

Experimental study about the influence of adhesive stiffness to the bonding strengths of adhesives for ceramic/metal targets

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defence Technology（防务技术） 2016年第2期12卷 188-200页

作者： W.sEIFERT E.sTRAssBURGER s.GREFEN s.sCHAARE Fraunhofer-Institute for High-speed Dynamics Ernst-Mach-Institute(EMI)Am Christianswuhr 279400 KandernGermany Rheinmetall Ballistic Protection GmbH Neuer Weg 2447803 KrefeldGermany

The aim of the investigations presented here was to understand how the stiffness of the adhesive affects the failure of ceramic tiles adhered to metallic backings. The working hypothesis was that varying the adhesive stiffness could have the same effect on the ballistic performance as a variation of the adhesive *** different projectile/target combinations were utilized for ballistic tests in order to generate extremely different loading conditions. With targets consisting of 6 mm aluminum oxide ceramic and 6 mm aluminum backing, complete penetration occurred in each test with 7.62 mm tungsten carbide core AP ammunition at an impact velocity of 940 m/s. In contrast, with ceramic tiles of 20 mm thickness on 13 mm steel backing,no penetration of the ceramic occurred at the impact of a 7.62 mm ball round at 840 m/*** different types of adhesive(high-strength till high-flexible) were tested in both configurations. The elongation of the adhesive layer, the deformation of the metallic backing and the failure of the ceramics were observed by means of a high-speed camera during the projectile/target *** results of the ballistic tests showed that a higher fracture strain caused a larger deformation of the backing compared to adhesives, which exhibit a high tensile strength and low fracture *** experimental results indicate that the damage behavior of the ceramic/metal composites depends on the absolute elongation of the adhesive layer. This can be controlled either by the thickness or the stiffness of the bonding layer.

关键词：氧化物陶瓷粘结层金属靶刚度强度影响实验陶瓷/金属复合材料粘接

Characteristics of soil seed bank in plantation forest in the rocky mountain region of Beijing, China

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Journal of Forestry Research 2013年第1期24卷 91-97页

作者： HU Zeng-hui YANG Yang LENG Ping-sheng DOU de-quan ZHANG Bo HOU Bing-fei Garden department Beijing University of Agriculture

We investigated characteristics （scales and composition） of soil seed banks at eight study sites in the rocky mountain region of Beijing by seed identification and germination monitoring. We also surveyed the vegetation communities at the eight study sites to explore the role of soil seed banks in vegetation restoration. The storage capacity of soil seed banks at the eight sites ranked from 766.26 to 2461.92 seeds·m？2. A total of 23 plant species were found in soil seed banks, of which 63–80% of seeds were herbs in various soil layers and 60% of seeds were located in the soil layer at 0–5 cm depth. Biodiversity indices indicated clear differences in species diversity of soil seed banks among different plant communities. The species composition of aboveground vegetation showed low similarity with that based on soil seed banks. In the aboveground plant community, the afforestation tree species showed high importance values. The plant species originating from soil seed banks represented natural regeneration, which also showed relatively high importance values. This study suggests that in the rocky mountain region of Beijing the soil seed banks played a key role in the transformation from pure plantation forest to near-natural forest, promoting natural ecological processes, and the role of the seed banks in vegetation restoration was important to the improvement of ecological restoration methods.

关键词： Rocky mountain region of Beijing soil seed bank plantcommunity plant diversity vegetation regeneration

Children in Disaster Risk Reduction in Portugal: Policies,Education,and (Non) Participation

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International Journal of Disaster Risk science 2017年第3期8卷 246-257页

作者： Ana delicado ussara Rowland susana Fonseca Ana Nunes de Almeida Luísa schmidt Ana sofia Ribeiro Instituto de Ciências sociais Universidade de Lisboa1600-189 LisbonPortugal

International agencies and scientific research have been calling for the inclusion of children in disaster preparedness and risk reduction, to hear their voices in order to address their specific needs and vulnerabilities and harness their capabilities in terms of building community resilience. This article assesses the roles ascribed to children in policy and education for disaster risk reduction in Portugal. The approach is based on a scoping methodology that encompasses document analysis and interviews with national and local stakeholders and policymakers in the disaster risk reduction field. The research is carried out within the scope of a European funded project, CUIDAR Cultures of Disaster Resilience among Children and Young People. More specifically, the article provides an overview of the discourses on the roles ascribed to children in urban disaster risk reduction(DRR). The authors maintain that although children are often taken as a target group in urban disaster prevention and management, they are seldom considered in terms of active participation in disaster risk reduction programs in the Portuguese context. Nevertheless, our analysis shows that there is a growing awareness of the relevance of active participation by children in order to create successful DRR.

关键词： Children’s nonparticipation Disaster risk reduction Emergency planning Portugal Risk education

Three-dimensional flow of Oldroyd-B fluid over surface with convective boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2013年第4期34卷 489-500页

作者： T.HAYAT s.A.sHEHZAD A.ALsAEDI M.s.ALHOTHUALI department of Mathematics Quaid-i-Azam University department of Electrical and Computer Engineering Faculty of Engineering King Abdulaziz University

The present study addresses the three-dimensional flow of an Oldroyd-B fluid over a stretching surface with convective boundary conditions. The problem formulation is presented using the conservation laws of mass, momentum, and energy. The solutions to the dimensionless problems are computed. The convergence of series solutions by the homotopy analysis method （HAM） is discussed graphically and numerically. The graphs are plotted for various parameters of the temperature profile. The series solutions are verified by providing a comparison in a limiting case. The numerical values of the local Nusselt number are analyzed.

关键词： three-dimensional flow Oldroyd-B fluid convective boundary condition