A New Dynamic Protocol Analysis Model

2013 ◽  
Vol 765-767 ◽  
pp. 1761-1765
Author(s):  
Fu Lin Li ◽  
Jie Yang ◽  
Hong Wei Zhou ◽  
Ying Liu

Traditional static analysis methods such as formal validation and theorem proving were used to analyze protocols security previously. These methods can not measure and evaluate actual security of protocols accurately for the setting and suppose are far from the actual conditions. This paper proposes a new dynamic protocol analysis model. The system based on the model can be used to active test in actual running conditions, analyze known protocols security, integrity, robustness, and analyze unknown protocols online, provide support for protocol designer. The systems structure, working flow and implementation of key modules are described. The experimental results validate the validity of the models design.

2013 ◽  
Vol 1 (3) ◽  
pp. 48-65
Author(s):  
Yuting Chen

A concurrent program is intuitively associated with probability: the executions of the program can produce nondeterministic execution program paths due to the interleavings of threads, whereas some paths can always be executed more frequently than the others. An exploration of the probabilities on the execution paths is expected to provide engineers or compilers with support in helping, either at coding phase or at compile time, to optimize some hottest paths. However, it is not easy to take a static analysis of the probabilities on a concurrent program in that the scheduling of threads of a concurrent program usually depends on the operating system and hardware (e.g., processor) on which the program is executed, which may be vary from machine to machine. In this paper the authors propose a platform independent approach, called ProbPP, to analyzing probabilities on the execution paths of the multithreaded programs. The main idea of ProbPP is to calculate the probabilities on the basis of two kinds of probabilities: Primitive Dependent Probabilities (PDPs) representing the control dependent probabilities among the program statements and Thread Execution Probabilities (TEPs) representing the probabilities of threads being scheduled to execute. The authors have also conducted two preliminary experiments to evaluate the effectiveness and performance of ProbPP, and the experimental results show that ProbPP can provide engineers with acceptable accuracy.


2020 ◽  
Vol 26 (9) ◽  
pp. 1579-1591
Author(s):  
Sang-Woo Baek ◽  
Nahm-Gyoo Cho ◽  
Dong-Hyeok Lee

Purpose This paper aims to propose a method for manufacturing multi-material monolithic structures with flexible materials to construct the elastic body by using a dual-nozzle three-dimensional printer to develop a piezoelectric (PZT)-driven micropositioning stage with three degrees of freedom (3-DOF) and flexure hinges. Design/methodology/approach Polylactic acid (PLA) and nylon were used for the lever structure’s frame and flexure hinge, respectively. Additionally, the stage consisted of three PZT actuators for fine movement in the nanometer scale in 3-DOF (x, y and θ-directions). For the design of the stage, the kinematic analysis model and the finite element method (FEM) analysis was undertaken for comparing between PLA with nylon (multi-material), PLA (single material) and aluminum (conventional-material). In addition, two verification experiments were implemented for the fabricated prototype stage. First, to evaluate various assessments (lever ratio, hysteresis, coupling error and resolution), a measurement is carried out using the three capacitive sensors. Then, a two-camera-vision measurement experiment was performed to verify the displacement and lever ratio over the full-scale working range of the fabricated positioning stage, and the results from the experimentation and the FEM analysis were compared. Findings The authors confirmed enhancements in the properties of the lever structure frame, which requires stiffness and of the hinge, which requires flexibility for elastic deformation. Comparing FEM analysis and experimental results, although the performance as shown by experimental results was lower: the maximum difference being 3.4% within the end-point working range; this difference was sufficient to be a plausible alternative for the aluminum-based stage. Originality/value Multi-material monolithic-structure fabrication has an effective advantage in improving the performance of the stage, by using a combination of materials capable of reinforcing the desired characteristics in the necessary parts. It was verified that the fabricated stage can substitute the aluminum-based stage and can achieve a higher performance than single-material stages. Thus, precise-positioning stages can be manufactured in many kinds of structures with various properties and contribute to weight reduction and low costs for application equipment.


1970 ◽  
Vol 185 (1) ◽  
pp. 665-674 ◽  
Author(s):  
R. Ali ◽  
J. L. Hedges ◽  
B. Mills

The finite element technique has been used for the static analysis of a chassis structure. A computer program was developed to predict static deflections under bending and torsion loads. The program is quite general, but its use has been restricted to structures consisting of beam elements only. The effects of shear deflections and tapered beams and manufacturing tolerances of cross sections are also considered. Predictions of static deflections are compared with experimental results.


Author(s):  
MANUEL PERALTA ◽  
SUPRATIK MUKHOPADHYAY

This article shows a novel program analysis framework based on Lewis' theory of counterfactuals. Using this framework we are capable of performing change-impact static analysis on a program's source code. In other words, we are able to prove the properties induced by changes to a given program before applying these changes. Our contribution is two-fold; we show how to use Lewis' logic of counterfactuals to prove that proposed changes to a program preserve its correctness. We report the development of an automated tool based on resolution and theorem proving for performing code change-impact analysis.


2021 ◽  
Author(s):  
Ricardo Lemos De Souza ◽  
Fabiana Zaffalon Ferreira ◽  
Silvia Da Silva Botelho

2006 ◽  
Vol 18 (5) ◽  
pp. 556-563 ◽  
Author(s):  
Guangping Lan ◽  
◽  
Shugen Ma ◽  

The novel crawler-driven robot we designed used a planetary gear reducer as the major power transmission device and provides two types of output in different form using one actuator. The crawler mechanism switches between two outputs autonomously based on the terrain. Using this feature, the crawler-driven robot is expected to perform adaptably and effectively in irregular environments. We conducted 2-dimensional quasi-static analysis to explain the condition under which the robot performs some locomotion modes in an irregular environment. Experimental results showed that the crawler-driven robot moves over even ground and uses efficient locomotion modes or postures to adapt autonomously to irregular environments.


2013 ◽  
Vol 288 ◽  
pp. 109-113
Author(s):  
Li Shan Zhou

A novel cataluminescence(CTL)-based sensor array consisting of 9 types of catalytic nanomaterials was developed for the determination and identification of harmful gas. The sensing nanomaterials, including nano-sized metal oxides, carbonates and decorated nanoparticles, have been selected carefully. A 3 x 3 array was integrated by depositing these nanosized catalysts onto the ceramic chip. Dynamic and static analysis methods were utilized to characterize the performance of the sensor array to 4 kinds of harmful gas. Each compound gives its unique CTL pattern after interact with the sensor array, which can be employed to recognize ether, acetone, chloroform, and toluene. PCA was conducted to classify the harmful gas and the plots showed that the groups were well classified. In addition, the patterns obtained at different working temperature and the analytical characteristics of array were investigated. The CTL-based sensor array shows promising perspective for the recognition and discrimination of harmful gas.


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