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Modified Hopkinson pressure bar apparatus is widely used to investigate the dynamic fracture behavior of materials at higher rate loading. While using a small sample for fracture toughness testing, plane strain conditions are compromised. In the current work, a large diameter two-bar/ three-point bend fracture setup is used to analyze stress wave propagation behavior within a larger cracked specimen. The experimental setup model consists of striker, incident bar, loading pin, cracked three-point specimen, span and transmission bar. The model is prepared using ANSYS software and the transient dynamic analysis technique is used to simulate the dynamic load. The effects of increased transient time on the stress wave propagation behavior within the cracked sample and the stress and strain values at the crack tip of the three-point bend specimen are analyzed. In addition, the effects of the hollow striker, the hollow incident bar and the specimen span are studied. It is found that during large specimen testing, an increase in the transient time results in the lower stress and strain values in the specimen crack-tip. The relationship of the specimen span, the striker and the incident bars with the strain values in the specimen is analyzed and a method for the three-point bend specimen testing at the higher strain rates is also proposed.

Mechanical model and simulation model of shaper quick-return mechanism are introduced based on ADAMS. The number of rigid bodies is reduced by using composite joints constraint . It doesn’t need any other softwares and data interfaces in the simulation.The results prove the correctness of the simplified model.It improves the design efficiency and speed of simulation and provides a theoretical basis for the design and analysis of other six-bar mechanism.

The paper digs out useful conclusions for businesses from the mass of product reviews. To conduct commodity pricing, merchandise improvements provide a basis so as to promote sales performance. The paper discusses the product reviews of emotional connotation. It summed up the current situation development of emotional analysis on product reviews. It analyzes the significant commercial value of product reviews. Product reviews explores the relationship between emotion and sales performance analysis. We can research the technical implementation process of reviews.

Saas is an abbreviation for Software-as-a-service, it is a completely innovative software application mode provided via Internet. As a new IT service model, SaaS has two sides. This article focuses on analysis the existent security risks of SaaS and put forward a series of countermeasures and suggestions to address these issues from the technical aspects.

Hopkinson pressure bar apparatus is extensively used for the measurement of the dynamic fracture properties. For accurate measurement of the dynamic fracture properties we need to understand concepts and principles associated with the test setup. The understanding of stress wave in the bar and specimen is also very important. In the current work, ANSYS LS-DYNA software is used to simulate the propagation behavior of the time based loading and generation of stress wave. The stress and strain plots in the specimen and the incident bar are obtained as an output of the analysis. The analysis of the plots suggest that, for the same time duration the rising trend is observed for the plots of stress and strain of incident bar whereas a sine wave trend is observed for the plots in the specimen.

For the Comprehension of the dynamic mechanical properties of the materials under the dynamic loading, Hopkinson pressure bar apparatus is used. During the compression testing of the low impedance materials the use of the hollow transmission bar is common. In the current work, the analysis is performed to analyze the effects of hollow transmission and incident bars on the specimen testing for the large diameter compression setup. Complete model of the setup is prepared using the ANSYS software and the simulation of loading is done using the LS-DYNA software. The results of analysis indicate that for the large compression testing setup, solid bars can be replaced with hollow bars. By using the hollow transmission bar the objective of high strain rate testing is also obtained.

Based on the Swarm platform and adaptive multi-agents of complex system, the simulation model of mobile telecommunications market’s regulation has been developed with the aim to simulate the effects of regulatory policies. Through the different simulation results, the implementation of regulatory policies having impact on the mobile telecommunications market can be analyzed, which provides theoretical support and basis for the future development of mobile telecommunications market’s regulatory policy, in order to avoid the unpredictable and potential risk of the regulatory policies in the effective implementation process.

According to the experiments study of sulfuric acid saline soil, the formula of compression coefficient with the changes of moisture content, salt content, initial dry density and temperature is presented, and the law of single influencing factor on sulfuric acid saline soil compression are analyzed in the paper.

According to the experiments study, the formulas of strength with the changes of moisture content, natural dry density, cement dosage are presented. Applicable range of cement mixing pile to consolidate soft soils is determined which can be used to guide the using of cement mixing pile and provide reference for design or research departments at the same time.

In this paper, solar thermal utilization methods in hospitals, schools, hotels and factories in a typical Southern China city, e.g., Dongguan City, were investigated, which lead to the understanding of the heating methods in different types of buildings and the application ratio of different kinds of renewable heating systems, e.g., solar water heater, in all kinds of buildings. These will help reveal the usage of renewable energy for heating and its development in this region of China.

This paper studied the thermal and physical properties of a new solar solid desiccant material, including the equivalent thermal conductivity under different moisture content conditions and penetrability under different simulated solar radiation. The results showed that the equivalent thermal conductivity of the material was related to the moisture content and water saturation. In unsaturated state, the equivalent thermal conductivity increased with the increase of the moisture content and presented a linear relation in certain range. When reached saturation, the equivalent thermal conductivity decreased with the increase of the moisture content. These figures could provide the basis for the determination of the thickness of the dehumidification bed and optimization of the design of the dehumidification system.

This paper expects to get the real-time changes of traffic flow by researching the relationships among the three basic parameters flow, speed and occupancy. we firstly carries out the statistical correlation analysis and grey relational analysis to study the connection between the traffic flow parameters flow and speed, flow and occupancy to get a conclusion that there doesn’t exist a significant linear relationship between neither of the comparisons, and the influence of speed on the flow is a little bigger than that of occupancy. Then we try to establish the binary linear regression model without the intercept and GM (0,3) model to do the data fitting, the final simulation results illustrate that the two methods has effects in some extent, also explain the complexity of traffic flow.

Among many user authentications over insecure networks, password authentication is simple, convenient and widely adopted one. Chen and Lee proposed a new hash-based password authentication using smart card and claimed that their scheme could resist seven attacks as listed in their paper. However, in this paper, it is pointed out that Chen-Lee’s scheme is vulnerable to off-line password guessing, replay and impersonation attacks when the smart card is lost or stolen.