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The article discusses how many colleges are producing high-performance computing (HPC) graduates who are able to contribute to companies and governments on day one of employment, and it mentions how employers are searching for candidates who are able to solve computing-related problems. Computing competency and college curricula are assessed, as well as job skills and professional knowledge regarding critical thinking and task planning. Personal attitude-related disposition is also mentioned.

The effects of different surface modifiers on the CO2adsorption capacity of coal-based activated carbons were studied, and the diffusion behavior, adsorption kinetics and thermodynamic parameters of CO2in activated carbons were analyzed. The results show that compared with ethylene glycol, 1,2-propylenediamine and zinc chloride, potassium hydroxide and sodium hydroxide can greatly improve CO2adsorption capacity. The adsorption rate is faster, and the adsorption capacity is larger, with the maximum CO2adsorption capacity being 33.54 mL/g. Fick's law can well describe the diffusion behavior of CO2in activated carbon. The addition of a surface modifier can increase the diffusion coefficient. The diffusion of CO2in activated carbon falls into the category of crystal diffusion. The adsorption kinetics of CO2before and after surface modification follow the Bangham equation. During the adsorption process, δ H < 0, δ G < 0, δ S < 0. Surface modification can reduce adsorption heat and promote adsorption, and the adsorption process is dominated by physisorption.

A Zn1−xCox-ZIF@Zn1−xCoxO hybrid photocatalyst, doped with different amounts of Co, was successfully fabricated through a novel metal organic framework (MOF)-derived method. The synthesis procedure consists of the initial preparation of Zn1−xCox-ZIF and then the formation of Zn1−xCoxO viaZn1−xCox-ZIF-derived in situtransformation with AgNO3to obtain the Zn1−xCox-ZIF@Zn1−xCoxO hybrid photocatalyst. All samples were characterized by XRD, SEM, TEM, UV-vis, and FT-IR. The photocatalytic activity of all samples was evaluated by degradation of rhodamine B (RhB) solution under UV light and visible light. The results show that Zn1−xCox-ZIF@Zn1−xCoxO hybrid photocatalysts exhibit high photocatalytic activity, and the doping of Co has great influence on the photocatalytic activity of Zn1−xCox-ZIF@Zn1−xCoxO. Among these photocatalysts, Zn0.95Co0.05-ZIF@Zn0.95Co0.05O exhibits the highest photocatalytic activity. Zn0.95Co0.05-ZIF@Zn0.95Co0.05O can degrade 99.26% RhB under UV light, which is even higher than P25 (92.62%). Zn0.95Co0.05-ZIF@Zn0.95Co0.05O also exhibits a photoresponse to visible light, and was able to degrade 98.15% RhB under visible light irradiation. Furthermore, Zn0.95Co0.05-ZIF@Zn0.95Co0.05O also can degrade 95.83% RhB under visible light after four repeated cycles. The results indicate that Zn0.95Co0.05-ZIF@Zn0.95Co0.05O can be used as a highly efficient photocatalyst upon degradation of organic dye.

Metro-based underground logistics (M-ULS) can relieve the pressure of urban traffic and avert the road congestion through coordinating with ground logistics system. A bi-level node location model is proposed based on the ground-underground logistics distribution mode. The cost of delivery and pickup from the perspective of service companies and customers are minimized as the upper and lower objectives. Since the model is belonged to NP-hard problem, the simulated annealing algorithm (SA algorithm) whose new solution generation part was improved according to the characteristics of the model is used to solve the problem. In the case analysis part, the distribution nodes and customer points close to Nanjing Metro Line 3 were selected to verify the validity of the model and algorithm. The result shows that the improved SA algorithm outperformed in taking less iteration times and obtaining better solutions. The total transportation cost of the system can be reduced by 21.7% with the optimized node location plan, and 63.6% of the ground transportation distance can be replaced by the underground transportation, such results are also obtained when the cargo demand increases by 1.5 times and 2 times, which verifies the advantages of M-ULS node location in reducing truck emission and total delivery cost.

Computations using the direct simulation Monte Carlo method are presented for hypersonic rarefied flow over a supersonic combustion ramjet (scramjet). The primary object of this study is to examine the geometrical effects of a step jump on flow field structures. The sensitivity of internal flow properties, including shock interaction, vortex, pressure and temperature distributions to free-stream Mach number and configuration variations, such as the step height and the ratio of isolator to combustor, is analyzed. Comparisons are made between cases with various configurations, based on surface pressure and temperature. It is shown that different isolator to combustor ratios and expansion ratios cause profoundly different results. The flow structures generated in the scramjet inlet directly affect vehicles operating at high speeds and high altitudes.

Abstract: A class of conservative discrete ordinate method (C-DOM) for the Bhatnagar–Gross–Krook (BGK) model Boltzmann equation is presented. The C-DOM is the extension of the discrete ordinate method in my previous study (Yang and Huang, 1995 ). In the C-DOM, a conservative molecular collision process is employed and thus the conservation properties of the collision integral are maintained at the molecular level. For a broad range of Knudsen number, several test problems, including unsteady shock-tube problem and supersonic/hypersonic flows over circular cylinder, are utilized to demonstrate the performance and validity of the DOM and C-DOM. Results show that the C-DOM can greatly reduce the computer time and memory requirements in hypersonic rarefied gas flow computations. [Copyright &y& Elsevier]

Abstract: The preconditioned weighted essentially non-oscillatory (P-WENO) solver for viscous flows (Huang et al. (2009) ) is extended to non-inertial reference frames. In the present scheme, patched multi-block grid system is employed and parallel computing is adopted as well. With the present parallel P-WENO solver, three-dimensional flows of the Phase VI Rotor from National Renewable Energy Laboratory (NREL) can be simulated and analyzed for different wind speeds. Our simulation results show good agreement with the numerical predictions based on incompressible Navier–Stokes (N–S) equations as well as the available wind tunnel data from NREL. The flow phenomena, including separation and attachment line, can be captured by the present scheme. The parallel strategy adopted is a block-domain decomposition method for the patched multi-block grid system. To balance the load among different computing nodes, a Tabu search algorithm is adopted for the parallelization. The parallel efficiency of the parallel P-WENO scheme is examined for node numbers ranging from 1 to 64. It is found that the parallel efficiency is monotonically decreased as the node number adopted is increased; the parallel efficiency is retained over 90% for all cases of different node numbers. Due to the high parallel efficiency, our parallel P-WENO solver is validated for applying to practical fluid problems from compressible to incompressible limits. [Copyright &y& Elsevier]

Demodulation based on a long-period grating (LPG) in a photonic crystal fiber (PCF) with differential processing was proposed to eliminate the noise of fiber sensors and raise the accuracy of the highly-birefringent fiber loop mirror (HiBi-FLM) temperature sensor. Utilizing the property temperature insensitive and the filtering function of the LPG in PCF, the intensities of two signals located respectively within the positive and negative linear region of the LPG's transmission spectrum can be monitored simultaneously and accurately. The noise of fiber sensors is eliminated effectively by the algorithm of two signals, since the two signals (also including the noise of fiber sensors) transmit through the same way to the monitor. Experimental results show that the proposed demodulation eliminates not only all of power fluctuations in the system, but also raises the accuracy of the sensor. The value of the algorithm remains constant when the power of light source varies ±10% and the relative error between the measured temperature change and the true change is only 0.34%. Compared with the sensing without the algorithm, the accuracy increases from~90.5% to ~99.7%.

Using the extended homogenous balance method, we obtain abundant exact solution structures of a (2+1)-dimensional integrable model, the generalized Nizhnik-Novikov-Veselov equation. By means of the leading order term analysis, the nonlinear transformations of generalized Nizhnik-Novikov-Veselov equation are given first, and then some special types of single solitary wave solution and the multisoliton solutions are constructed.

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Comparative studies of double δ-doped InAlAs/InGaAs metal-oxide-semiconductor metamorphic high electron mobility transistors (MOS-MHEMTs) with different compressive-strained and tensile-strained channel structures have been made. In addition to the strain engineering of the heterostructure, the MOS-gate design is also integrated by using the cost-effective H2O2oxidization technique. The tensile (compressive)-strained channel is devised by the In0.52Al0.48As/In0.41Ga0.59As (In0.52Al0.48As/In0.63Ga0.37As) heterostructure. Device characteristics with respect to different channel structures are physically studied. The impact-ionization-related kink effects in MHEMTs are significantly suppressed by the MOS-gate. Atomic force microscopy (AFM) and low-frequency noise (LFN) analysis were used to study the surface roughness and interface quality. As compared to the compressive-strained MOS-MHEMT and conventional Schottky-gate devices, the present tensile-strained MOS-MHEMT design has demonstrated improved transconductance gain (gm), current drive, intrinsic voltage gain (AV), and power performance.