Performance benchmarking of deep learning framework on Intel Xeon Phi

The Journal of Supercomputing - With the success of deep learning (DL) methods in diverse application domains, several deep learning software frameworks have been proposed to facilitate the usage...     

Simultaneous optimal integration of water utilization and heat exchange networks using holistic mathematical programming

A systematic holistic mathematical programming (HMP) is proposed to formulate a mixed integer nonlinear programming (MINLP) model for one-step optimization of water-allocation and heat exchange network (WAHEN) designs with single- or multi-contaminant water streams. The proposed model formulation and solution strategy are believed to be superior to the available ones in the following aspects. First, a comprehensive representation combining two separate superstructures is adopted to capture the structural characteristics of the integrated WAHEN. Then, a hybrid optimization strategy integrating stochastic and deterministic components is developed for the resulting MINLP model and, also, an interactive iteration method is adopted based on sensitivity analysis to guide the search toward a potential global optimum. Finally, evolutionary strategies and manipulations are executed to enhance WAHEN configurations. Two illustrative examples are presented to demonstrate the validity and advantages of the proposed approach.     

Evaluating Relationship of Consistency Ratio and Number of Alternatives on Rank Reversal in the AHP

This article shows the simulation result of the rank reversal phenomenon with respect to the changing values of consistency ratio and the number of alternatives. The simulation result reveals that the number of alternatives and the consistency ratio have significant effect on the occurrence of rank reversal. The more the number of alternatives is, the higher the probability of rank reversal occurrence becomes. The more inconsistent the judgment is, the more likely the rank reversal will occur. This result is based on two-way analysis of variance in which the number of alternatives and the consistency ratio are considered as factors, and the probability of rank reversal occurrence is regarded as the response variable. The number of alternatives of 4 to 7 and the consistency ratios ranging between 0.02 and 0.20 are investigated. The observation is based on the rank reversal that occurs after adding a copy of the best existing alternative.     

Catalytic co-gasification of coconut shells and oil palm fronds blends in the presence of cement,dolomite, and limestone: Parametric optimization via Box Behnken Design

In this study, Response Surface Methodology (RSM) in combination with Box-Behnken Design (BBD) was used to optimize the temperature, catalyst loading, and blending ratio for a co-gasification process. The catalytic co-gasification of coconut shells (CS) and oil palm fronds (OPF) blends was performed in the presence of cement, dolomite, and limestone catalysts. A combined effect of temperature, catalyst loading, and blending ratio on production of H₂, CO, and tar formation was investigated by using a BBD approach. The results showed the strongest influence of the process temperature on H₂ and CO yield, and tar formation followed by the catalyst loading and blending ratio. A catalyst loading of 30 wt%, process temperature of 900 °C and blending ratio of CS50:OPF50 were predicted as the optimized conditions for the reported co-gasification results. The highest H₂ yield of 20.64 vol% was produced during catalytic co-gasification of the blended biomass with limestone followed by the cement (18.22 vol%) and dolomite (14.99 vol%). Under optimized process conditions, lowest tar concentration of 0.87 g/Nm³ was obtained with limestone follow by the cement (1.42 g/Nm³) and dolomite (2.13 g/Nm³). However, blending ratio did not affect H₂, CO yield, and tar formation appreciably. Conclusively, the mixing ratio of CS and OPF would have a negligible role in controlling the process output.     

东北地区传统发酵食品中两株植物乳杆菌的安全性评价

针对已分离的植物乳杆菌L12和L20通过体外和体内两种方法进行安全性评价。通过体外实验测定乳酸水解活性抗生素敏感性，胆盐水解酶活性，D-乳酸含量，γ溶血等指标；体内实验是对小鼠进行短期口服毒性的研究，口服0.2 mL（109 CFU/mL）的实验性细菌溶液30 d。结果表明，体外实验中，两株菌株均具有良好的抗氧化活性，对抗生素敏感性高，胆盐水解酶活性高，D-乳酸含量低，γ溶血；体内实验中灌胃给药对治疗小鼠的生长、行为、摄食量、器官重量或组织病理学分析均无不良影响。与对照组相比，益生菌组小鼠血清MDA浓度和肝脏GSH含量差异有统计学意义(P<0.05)。这些结果表明，菌株L12和L20是非致病性的，人直接食用是安全的。     

Direct Formation of Titanium Carbide via In Situ Carbothermal Reduction of TiO2/Carbon Cladding for Coating Application

Protection of Metals and Physical Chemistry of Surfaces - In situ direct formation of titanium carbide (TiC) was realized via tungsten inert gas (TIG) arc surface cladding using titanium dioxide...     

Process design and techno‐economic analysis of ethyl levulinate production from carbon dioxide and 1,4‐butanediol as an alternative biofuel and fuel additive

Carbon dioxide capture, utilization, and storage (CCUS) is one of the promising negative emission technologies (NET). Within various CCUS routes available, CO₂ conversion into fuels is one of the attractive options. Currently, most of CO₂ conversion into fuels requires hydrogen, which is expensive and consume large energy to produce. Hence, a different route of producing fuel from CO₂ by utilizing 1,4‐butanediol as the raw material is proposed and evaluated in this study. This alternative route comprises production of levulinic acid from the reaction between CO₂ and 1,4‐butanediol and production of ethyl levulinate, an alternative biofuel and biofuel additive, via an esterification reaction of levulinic acid with ethanol. The process is designed and simulated according to the available data and evaluated in terms of its technical features. Because of the unavailability of reaction data for synthesis of levulinic acid from 1,4‐butanediol and CO₂, several assumptions were taken, which may implicate the accuracy of the studied design. This technical evaluation is followed by cost estimations and sensitivity analysis. Because of the free CO₂, the profitability of the plant depends strongly on the prices of the other chemicals and the price difference between 1,4‐butanediol (raw material) and ethyl levulinate (product). Monte Carlo simulation indicates that the proposed plant will always be profitable if the ethyl levulinate is slightly more expensive than the 1,4‐butanediol, highlighting that the process of producing ethyl levulinate from CO₂ is economically profitable. Future research should be directed towards a catalytic system that can effectively convert CO₂ into levulinic acid, by‐products produced from the two reaction steps, and reduce the excess ethanol used in the second reaction.     

Surface Temperatures Generated by Friction with Ceramic Materials

For tribological applications of ceramics, surface temperatures and thermal effects produced in frictional processes are important not only in influencing possible mechanisms of friction, wear, and lubricant film failure but also in initiating protective film formation, e.g., as in tribopolymerization. As part of a continuing combined experimental and theoretical study of surface temperatures generated by friction, the fundamental Greens function approach has been applied to a number of ceramics including those used in tribological applications such as bearings and advanced low heat-rejection ceramic engines. The ceramics examined consisted of (a) alumina, Al₂O₃, (b) single crystal sapphire, Al₂O₃, (c) partially stabilized zirconia, ZrO₂, (d) tungsten carbide, WC, (e) silicon carbide, SiC, and (f) silicon nitride, Si₃N₄. In addition, three forms each of silicon carbide and silicon nitride were included in this study, i.e., sintered, hot-pressed, and reaction-bonded.

Assuming a single area of real contact, calculated ratios of average surface temperature rise to coefficient of friction plotted against area of contact, velocity, and load on a logarithmic scale are presented for all the above ceramics for A-on-A (self-mating) contact as well as an example of a ceramic in sliding contact against steel. The results show that as expected, very high surface temperatures can be generated by some ceramics, particularly those having very low thermal conductivity (e.g., zirconia), high hardness, or a combination of both. However, not all ceramic combinations produce high temperatures. It is suggested that the information developed may be useful in understanding the wear behavior of ceramics as well as in designing novel anti-wear approaches for ceramic lubrication.     

On construction of a network log management system using ELK Stack with Ceph

The Journal of Supercomputing - A log management system is essential for the networks administrator. With a log management tool, we can collect, store, analyze, archive, and finally dispose of the...     

Synthesis of Pt-zeolite coated palladium alloys as catalytic membranes for hydrogen production

PdAu composite membranes were applied for the preparation of PtNaA-PdAu catalytic membranes for hydrogen production from the water gas shift reaction. In the first stage, the deposition of NaA zeolite on top of the PdAu alloys was optimized. Functionalization employing a 1.0 v/v % 3-aminopropyltriethoxysilane solution prior to both seeding and hydrothermal synthesis allowed obtaining a homogeneous and complete PdAu alloy surface coverage. Even though the NaA zeolite coverage decreased the pure hydrogen permeance at 623 K and 50 kPa in comparison with a PdAu membrane, the resistance to a CO containing stream was higher. From direct incorporation of Pt during the zeolite synthesis, a homogeneous, well-intergrown PtNaA zeolite coverage on top of a PdAu alloy membrane was obtained. PtNaA catalytic tubular membranes were evaluated in the water gas shift reaction at 673 K. The membranes were active and stable under reaction conditions, without evidence of methane formation.