• Title/Summary/Keyword: Frameworks

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SECURITY FRAMEWORK FOR VANET: SURVEY AND EVALUATION

  • Felemban, Emad;Albogamind, Salem M.;Naseer, Atif;Sinky, Hassan H.
    • International Journal of Computer Science & Network Security
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    • v.21 no.8
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    • pp.55-64
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    • 2021
  • In the last few years, the massive development in wireless networks, high internet speeds and improvement in car manufacturing has shifted research focus to Vehicular Ad-HOC Networks (VANETs). Consequently, many related frameworks are explored, and it is found that security is the primary issue for VANETs. Despite that, a small number of research studies have taken into consideration the identification of performance standards and parameters. In this paper, VANET security frameworks are explored, studied and analysed which resulted in the identification of a list of performance evaluation parameters. These parameters are defined and categorized based on the nature of parameter (security or general context). These parameters are identified to be used by future researchers to evaluate their proposed VANET security frameworks. The implementation paradigms of security frameworks are also identified, which revealed that almost all research studies used simulation for implementation and testing. The simulators used in the simulation processes are also analysed. The results of this study showed that most of the surveyed studies used NS-2 simulator with a percentage of 54.4%. The type of scenario (urban, highway, rural) is also evaluated and it is found that 50% studies used highway urban scenario in simulation.

Evaluation of marginal discrepancy in metal frameworks fabricated by sintering-based computer-aided manufacturing methods

  • Kaleli, Necati;Ural, Cagri;Us, Yesim Olcer
    • The Journal of Advanced Prosthodontics
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    • v.12 no.3
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    • pp.124-130
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    • 2020
  • PURPOSE. The aim of this in vitro study was to evaluate the effect of sintering procedures on marginal discrepancies of fixed partial metal frameworks fabricated using different sintering-based computer-aided design and computer/aided manufacturing (CAD/CAM) techniques. MATERIALS AND METHODS. Forty resin die models of prepared premolar and molar abutment teeth were fabricated using a three-dimensional (3D) printer and divided into four groups (n = 10) according to the fabrication method of metal frameworks used: HM (via hard milling), SM (via soft metal milling), L25 (via direct metal laser melting [DMLM] with a 25 ㎛ layer thickness), and L50 (via direct DMLM with a 50 ㎛ layer thickness). After the metal frameworks were fabricated and cemented, five vertical marginal discrepancy measurements were recorded in each site (i.e., buccal, facing the pontic, lingual, and facing away from the pontic) of both abutment teeth under a stereomicroscope (×40). Data were statistically analyzed at a significance level of 0.05. RESULTS. No statistically significant differences (P>.05) were found among the four axial sites of metal frameworks fabricated by sintering-based CAD/CAM techniques. The HM and L25 groups showed significantly (P<.001) lower marginal discrepancy values than the SM and L50 groups. CONCLUSION. Marginal discrepancy in the sites facing the pontic was not influenced by the type of sintering procedure. All fabrication methods exhibited clinically acceptable results in terms of marginal discrepancies.

Flexural strengths of implant-supported zirconia based bridges in posterior regions

  • Rismanchian, Mansour;Shafiei, Soufia;Nourbakhshian, Farzaneh;Davoudi, Amin
    • The Journal of Advanced Prosthodontics
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    • v.6 no.5
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    • pp.346-350
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    • 2014
  • PURPOSE. Impact forces in implant supported FDP (fixed dental prosthesis) are higher than that of tooth supported FDPs and the compositions used in frameworks also has a paramount role for biomechanical reasons. The aim of this study was to evaluate the flexural strength of two different zirconia frameworks. MATERIALS AND METHODS. Two implant abutments with 3.8 mm and 4.5 mm platform were used as premolar and molar. They were mounted vertically in an acrylic resin block. A model with steel retainers and removable abutments was fabricated by milling machine; and 10 FDP frameworks were fabricated for each Biodenta and Cercon systems. All samples were thermo-cycled for 2000 times in $5-55^{\circ}C$ temperature and embedded in $37^{\circ}C$ artificial saliva for one week. The flexural test was done by a rod with 2 mm ending diameter which was applied to the multi-electromechanical machine. The force was inserted until observing fracture. The collected data were analyzed with SPSS software ver.15, using Weibull modulus and independent t-test with the level of significance at ${\alpha}=.05$. RESULTS. The mean load bearing capacity values were higher in Biodenta but with no significant differences (P>.05). The Biodenta frameworks showed higher load bearing capacity ($F_0=1700$) than Cercon frameworks ($F_0=1520$) but the reliability (m) was higher in Cercon (m=7.5). CONCLUSION. There was no significant difference between flexural strengths of both zirconia based framework systems; and both Biodenta and Cercon systems are capable to withstand biting force (even parafunctions) in posterior implant-supported bridges with no significant differences.

Effect of different veneering techniques on the fracture strength of metal and zirconia frameworks

  • Turk, Ayse Gozde;Ulusoy, Mubin;Yuce, Mert;Akin, Hakan
    • The Journal of Advanced Prosthodontics
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    • v.7 no.6
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    • pp.454-459
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    • 2015
  • PURPOSE. To determine whether the fracture strengths and failure types differed between metal and zirconia frameworks veneered with pressable or layering ceramics. MATERIALS AND METHODS. A phantom molar tooth was prepared and duplicated in 40 cobalt-chromium abutments. Twenty metal (IPS d.SIGN 15, Ivoclar, Vivadent, Schaan, Liechtenstein) and 20 zirconia (IPS e.max ZirCAD, Ivoclar) frameworks were fabricated on the abutments. Each framework group was randomly divided into 2 subgroups according to the veneering material: pressable and layering ceramics (n=10). Forty molar crowns were fabricated, cemented onto the corresponding abutments and then thermocycled ($5-55^{\circ}C$, 10,000 cycles). A load was applied in a universal testing machine until a fracture occurred on the crowns. In addition, failure types were examined using a stereomicroscope. Fracture load data were analyzed using one-way ANOVA and Tukey HSD post-hoc tests at a significance level of 0.05. RESULTS. The highest strength value was seen in metal-pressable (MP) group, whereas zirconia-pressable (ZP) group exhibited the lowest one. Moreover, group MP showed significantly higher fracture loads than group ZP (P=.015) and zirconia-layering (ZL) (P=.038) group. No significant difference in fracture strength was detected between groups MP and ML, and groups ZP and ZL (P>.05). Predominant fracture types were cohesive for metal groups and adhesive for zirconia groups. CONCLUSION. Fracture strength of a restoration with a metal or a zirconia framework was independent of the veneering techniques. However, the pressing technique over metal frameworks resisted significantly higher fracture loads than zirconia frameworks.

Development of An Intelligent Agent Shell Supporting An Integrated Agent Building Language (통합 에이전트 구축 언어를 지원하는 지능형 에이전트 쉘의 개발)

  • Chang, Hai-Jin
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.12
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    • pp.3548-3558
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    • 1999
  • There are many kinds of multi-agent frameworks which support the high-level knowledge representation languages for providing intelligence to their agents. But, the agent programming interfaces of the frameworks require to use some general-purpose programming languages as well as tile knowledge representation languages. In general, knowledge representation languages and general-purpose programming languages are different in their levels and data representation models. The differences can make the problems about tile coupling of the elements which are necessary for developing intelligent agents. This paper describes a new type of intelligent agent shell INAS(INtelligent Agent Shell) version 2 which has developed to cope with the problems. Unlike the previous agent frameworks, INAS supports a high-level integrated agent building language for building intelligent agents by itself. Therefore, the development of intelligent agents by using INAS version 2 does not suffer from the problems of the previous agent frameworks. Through the development of several intelligent agents, we experienced that the agent building language of INAS version 2 could reduce the difficulties of developing intelligent agents.

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Hydrogen Storage Behaviors of Carbon Nanotubes/Metal-organic Frameworks-5 Hybrid Composites

  • Park, Soo-Jin;Lee, Seul-Yi
    • Carbon letters
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    • v.10 no.1
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    • pp.19-22
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    • 2009
  • In this work, the hydrogen storage behaviors of carbon nanotubes (CNTs)/metal-organic frameworks-5 (MOF-5) hybrid composites (CNTs/MOF-5) were studied. Hydrothermal synthesis of MOF-5 was conducted by conventional convection heating using 1-methyl-2-pyrrolidone (NMP) as a solvent. Morphological characteristics and average size of the CNTs/MOF-5 were also obtained using a scanning electron microscopy (SEM). The pore structure and specific surface area of the CNTs/MOF-5 were analyzed by N2/77 K adsorption isotherms. The capacity of hydrogen storage of the CNTs/MOF-5 was investigated at 298 K/100 bar. As a result, the CNTs/MOF-5 had crystalline structures which were formed by hybrid synthesis process. It was noted that the CNTs/MOF-5 can be potentially encouraging materials for hydrogen adsorption and storage applications at room temperature.

E-Transformation from EDI to Web-based B2B Frameworks

  • Kim, Minsoo;Ock, YoungSeok;Kim, Dongsoo
    • Industrial Engineering and Management Systems
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    • v.7 no.2
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    • pp.150-159
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    • 2008
  • Lots of EDI-VAN companies are in need of transforming their business transaction systems into Web-based e-Business frameworks because of high cost and closed structure of EDI systems. This research proposes several e-Transformation strategies for EDI-VAN companies to adopt Web-based e-Business frameworks such as ebXML and RosettaNet. Four transformation alternatives are presented and transformation procedure for a medium-sized company is described. The result of this work can be used as a practical guideline for EDI companies to develop their own transformation strategy suitable to its scale and capability, while minimizing the impacts on the pre-existing business processes and information systems.

Privacy-Aware Adaptable Web Services Using Petri Nets

  • Song, You-Jin;Yim, Jae-Geol
    • Journal of Information Processing Systems
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    • v.5 no.1
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    • pp.19-24
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    • 2009
  • Many researchers have developed frameworks that are capable of handling context information and can be adapted and used by any Web service. However, no research involving the systematic analysis of existing frameworks has yet been conducted. This paper examines the Context Framework, an example of existing frameworks, using a Petri net, and analyzes its advantages and disadvantages. Then, a Petri net model - with its disadvantages removed - is introduced, and a new framework is presented on the basis of that model. The proposed PAWS (Privacy Aware Web Services) framework has a expendability for context management and communicates flexible context information for every session. The proposed framework can solve overhead problems of context in SOAP messages. It also protects user privacy according to user preferences.

RELAXED PROXIMAL POINT ALGORITHMS BASED ON A-AXIMAL RELAXED MONOTONICITY FRAMEWORKS WITH APPLICATIONS

  • Agarwal, Ravi P.;Verma, Ram U.
    • East Asian mathematical journal
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    • v.27 no.5
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    • pp.545-555
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    • 2011
  • Based on the A-maximal(m)-relaxed monotonicity frameworks, the approximation solvability of a general class of variational inclusion problems using the relaxed proximal point algorithm is explored, while generalizing most of the investigations, especially of Xu (2002) on strong convergence of modified version of the relaxed proximal point algorithm, Eckstein and Bertsekas (1992) on weak convergence using the relaxed proximal point algorithm to the context of the Douglas-Rachford splitting method, and Rockafellar (1976) on weak as well as strong convergence results on proximal point algorithms in real Hilbert space settings. Furthermore, the main result has been applied to the context of the H-maximal monotonicity frameworks for solving a general class of variational inclusion problems. It seems the obtained results can be used to generalize the Yosida approximation that, in turn, can be applied to first- order evolution inclusions, and can also be applied to Douglas-Rachford splitting methods for finding the zero of the sum of two A-maximal (m)-relaxed monotone mappings.

Commonality and Variability Analysis Method for UML CASE Tool Frameworks (UML CASE 도구 프레임워크를 위한 공통성 및 가변성)

  • Choi, Hwan-Bok;Lee, Eun-Ser;Kim, Yun-Ho
    • The KIPS Transactions:PartD
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    • v.16D no.6
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    • pp.927-934
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    • 2009
  • This paper presents a commonality and variability analysis method for UML CASE tool frameworks. Commonality and Variability analysis increase extension and reusability by separating common area and variable area. We suggest class category based on property and the notation to represent commonality and variability. It is also implements frameworks based on analysis method and verify method using defect removal efficiency.