Abstract: In order to research thermal conductivity of fracture rock, fluid-heat coupling test and simulation are studied. Empirical equation of thermal conductivity is obtained and conductivity factor is ensured by test data. Based on the fluid-heat coupling model of heat-transfer, temperature field distribution of fracture rock is described. At the same time, the heat-transfer equation is discretized by using weighted residual Galerkin finite element. Combined with boundary condition and parameters, the temperature field in fractured rock mass is simulated by finite element method. The temperature of fractured rock mass under the action of the seepage is combined with the initial rock temperature, fluid temperature and the rate of the flow. Thermo-isoline is discontiguous at boundary of fracture, which shows that the seepage affects the distribution of temperature field. The change rate of temperture isoline is gradually reduced along the single fissure flow, therefore the rate of heat-transfer is decreased. The influence of fluid temperature to temperature distribution is small, but different fluid temperature obviously affects thermo-isoline.
Abstract: For regions without adequate strong ground motion records, a method is developed to establish strong ground motion attenuation relationships, based on the stochastic method. Sendai area of Japan is selected as the target, since there are enough data from seismographic observation for calculation, and those from strong ground motion observation and some empirical relationships for result testing. Three parameters related to regional source and crustal medium are inversed by the micro-Genetic Algorithm. Total of 240 records from 77 small events, recorded by F-net, are adopted for the inversion. Fourier spectra are adopted as the objective function. These parameters are then taken into the stochastic method to estimate PGA. The regional ground motion attenuation relationships are compared with some strong ground motion records from K-NET and some empirical relationships to illustrate the reliability of this method.
Abstract: Combined with an independent residential construction, using cooling load coefficient method based on the DEST software, the hourly cooling load calculation program is established, the hourly cooling load is calculated, and the distribution character of cooling load is analyzed. It can be concluded that the maximum cooling load appears in the afternoon between 14:00 to 16:00. In refrigeration seasons, the number of days whose maximum daily cooling load ranged from 40 to 50 W/m2 in summer is the most; however, the number of the ones whose peak value beyond 80 W/m2 is only 9 days. So the cooling load distribution indicates that the ratio of load operating is about more than 75 percent.
Abstract: This paper presents a real-time GPU-based visualization of dynamic terrain in excavator simulator, which is an interactive system for the purpose of training human operators and corresponding researches. Firstly, we establish the kinematic model of excavator, so as to trans-fer the bucket tip's reference trajectories to corresponding, required reference angle sequence for each joint and to control motion sequences of articulated hierarchies. Then, our method use GPU to create the DDHM and digging offset map, with which we can perform the terrain de-formation entirely in the GPU. In order to improve the visual quality, we also present a method of procedural texture for deformation terrain. Finally, the Real-Time Optimally Adapting Meshes (ROAM) algorithm is used to render the dynamic terrain effectively.
Abstract: A numerical simulation model for gasoline engine was established by GT-POWER in order to study the NOx emissions characteristic of vehicle engine fuelled with M40 (the methanol and the gasoline in volume ratio 40∶60) and was validated by Experimental data. Based on the model, the variable parameters study including air-fuel radio, compression radio and ignition advance angle were carried out. The model results showed that the compression radio and the air-fuel radio played an important role during the NOx emissions characteristic. There is a significant improvement of the NOx emissions with the compression ratio increases. The cylinder pressure increased with the improvement of the compression ratio brought out the NOx emissions rise. With the improvement of the air-fuel ratio, NOx emissions increased first and then decreased. A larger ignition advance angle can increase the pressure and the temperature of the cylinder.
Abstract: Amorphous silicon (a:Si) recrystalized to poly-silicon (poly:Si) in different gas environments by excimer laser annealing (ELA) is studied. Variations of threshold laser power for the generation of surface ablation in pure N2 gas and the mixture of N2:98% and O2:2% environments are also investigated, respectively. From experiments, it is found the combination of N2:98% and O2:2% gas can enhance the threshold laser power from 320mJ/cm2 to 390mJ/cm2 for the suppressing of surface ablation phenomenon. In the condition of average grain over 0.25um, the process window (i.e. laser power for processing ability) is 30mJ/cm2 for pure N2 only, but is 50mJ/cm2 for the combination of N2:98% and O2:2%.
Abstract: Being a natural composite material, bamboo’s biological anatomy structure, chemical components and particularities in mechanical properties have some influences on the processing and manufacturing of bamboo materials. Based on micromechanical analysis and the combination of structural features of its hollow type curved surface and cleavability, this paper discusses about the feasibility about extension design of bamboo pole as a whole for modeling elements, any possible varieties by vertical and horizontal segmentation for diversified combinational designs like enclosure and assembly; as well as rationality about designing products models in association with line-type materials after cleavage and separation. In the meantime, it presents difficulties in processing and utilization owing to bamboo material’s characteristics in geometric configurations such as small diameter, hollowness, multisections, thin wall and taperingness, and also its only longitudinal fibers.
Abstract: Most new materials are not mature since there are all kinds of uncertainties due to many factors, such as technical complexity, shifting objectives/scopes, and poor management. Application of a new material means we must accept all opportunities and threats, while it exists a lot of uncertain information in the process of decision making. This paper reviews the traditional methods of risk analysis, such as risk matrix, and introduces uncertain data in decision to describe two attributes of risk —probability and consequence. The data of risk collected is then processed based on prospect theory, take into account the behavior patterns and psychological factors which are not aware of in a traditional approach. At last, an example proves the improved risk analysis method is rational and scientific.
Abstract: Color design plan for modern design provides a new way of thinking. Color design plan in product design, to design results promote a convenient and accurate and strict scientific significance; For enterprise development and occupy the market marketing is of strategic significance; To reflect the product has a certain taste of culture connotation of meaning.