THE STUDY OF THE NON-STEADY KINETICS OF THE OXYDEHYDROGENATION OF ETHANE TO ETHYLENE OVER THE CATALYST OF Mo-V-Nb/Al_2O_3 BY THE TECHNIQUE OF TEMPERATURE PROGRAMMED TRANSIENT RESPONSE AND ELECTRIC CONDUCTIVITY

In this paper, instead of with the more expensive Fourier Transform Infrared Spectrometer(FTIR) a new technique of Temperature Programmed Transient Response(TP-TR) has been used with gas chromatography. Therefore, the TP-TR will be applied more widespreadly than ever before. With the technique of TP-TR and electric conductivity, the study is on the reaction mechanism and the adsorption behavior of the reactants and products to the present catalyst Mo-V-Nb/Al_2O_3 in the reaction from ethane through oxydehydrogenation to ethylene as the product. By Range-Kutta-Gill and Margarat methods, the kinetic parameters of the reaction elementary steps (i.e. rate constants, active energies and frequency factors) have been evaluated. The mathematical treatment coincides with the experimental results.

Does the ratio of the carpal tunnel inlet and outlet cross-sectional areas in the median nerve reflect carpal tunnel syndrome severity?

Although ultrasound measurements have been used in previous studies on carpal tunnel syndrome to visualize injury to the median nerve, whether such ultrasound data can indicate the severity of carpal tunnel syndrome remains controversial. The cross-sectional areas of the median nerve at the tunnel inlet and outlet can show swelling and compression of the nerve at the carpal. We hypothesized that the ratio of the cross-sectional areas of the median nerve at the carpal tunnel inlet to outlet accurately reflects the severity of carpal tunnel syndrome. To test this, high-resolution ultrasound with a linear array transducer at 5–17 MHz was used to assess 77 patients with carpal tunnel syndrome. The results showed that the cut-off point for the inlet-to-outlet ratio was 1.14. Significant differences in the inlet-to-outlet ratio were found among patients with mild, moderate, and severe carpal tunnel syndrome. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.29 between mild and more severe（moderate and severe） carpal tunnel syndrome patients with 64.7% sensitivity and 72.7% specificity. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.52 between the moderate and severe carpal tunnel syndrome patients with 80.0% sensitivity and 64.7% specificity. These results suggest that the inlet-to-outlet ratio reflected the severity of carpal tunnel syndrome.

Thread Private Variable Access Optimization Technique for Sunway High-Performance Multi-core Processors

The primary way to achieve thread-level parallelism on the Sunwayhigh-performance multicore processor is to use the OpenMP programming technique.To address the problem of low parallelism efficiency caused by slow accessto thread private variables in the compilation of Sunway OpenMP programs, thispaper proposes a thread private variable access technique based on privilegedinstructions. The privileged instruction-based thread-private variable access techniquecentralizes the implementation of thread-private variables at the compilerlevel, eliminating the model switching overhead of invoking OS core processingand improving the speed of accessing thread-private variables. On the Sunway1621 server platform, NPB3.3-OMP and SPEC OMP2012 achieved 6.2% and6.8% running efficiency gains, respectively. The results show that the techniquesproposed in this paper can provide technical support for giving full play to theadvantages of Sunway’s high-performance multi-core processors.

Parallel Region Reconstruction Technique for Sunway High-Performance Multi-core Processors

The leading way to achieve thread-level parallelism on the Sunwayhigh-performance multicore processors is to use OpenMP programming techniques.In order to address the problem of low parallel efficiency caused by highthread group control overhead in the compilation of Sunway OpenMP programs,this paper proposes the parallel region reconstruction technique. The parallelregion reconstruction technique expands the parallel scope of parallel regionsin OpenMP programs by parallel region merging and parallel region extending.Moreover, it reduces the number of parallel regions in OpenMP programs,decreases the overhead of frequent creation and convergence of thread groups,and converts standard fork-join model OpenMP programs to higher performanceSPMD modelOpenMP programs. On the Sunway 1621 server computer, NPB3.3-OMP and SPEC OMP2012 achieved 8.9% and 7.9% running efficiency improvementrespectively through parallel region reconstruction technique. As a result,the parallel region reconstruction technique is feasible and effective. It providestechnical support to fully exploit the multi-core parallelism advantage of Sunway’shigh-performance processors.

Depth-averaged Nonlinear k-ε Model and Technique for Its Program Development

Without the ‘rigid lid’ assumption, the depth averaged linear k-ε model can describe the change of water depth. However, it is incapable of accurately simulating turbulent flows, where the normal Reynolds stresses play an important role. A depth averaged nonlinear k-ε model is developed taking into account the stress relations described by Speziale. The depth averaged linear and nonlinear k-ε models can both be used to calculate the flow field near a side discharge into open channel flow, but the results of the nonlinear model are in much closer agreement with experimental results. Furthermore, the technique of changing the 2D linear k-ε program into a depth averaged, nonlinear program is presented.