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Developing Hybrid cell-edge and cell-node Dissipative Compact Scheme for Complex Geometry Flows

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Science China(Technological Sciences) 2013年第10期56卷 2361-2369页

作者： DENG XiaoGang JIANG Yi MAO MeiLiang LIU HuaYong TU GuoHua State Key Laboratory of Aerodynamics China Aerodynamics Research and Development Center National University of defense Technology China Aerodynamics research and development Center

Developing high resolution finite difference scheme and enabling the use of this scheme on complex geometry are the aims of this *** resolution has been achieved by Dissipative Compact Schemes(DCS),however,according to the recent research,applications of DCS on complex geometry may have serious problem for that the Geometric Conservation Law(GCL)is not satisfied,and this may cause numerical *** cope with this problem,a new scheme named Hybrid cell-edge and cell-node Dissipative Compact Scheme(HDCS)has been *** formulation of the HDCS contains two ***,a new central compact scheme is formulated for the purpose of conveniently fulfilling the GCL,and then dissipation is added on the central scheme by high-order dissipative interpolation of cell-edge *** solutions of Euler and Navier-Stokes equations show that the HDCS can be applied successfully on complex geometry,while the DCS may suffer numerical ***,high resolution of the HDCS may be observed in the test of scattering of acoustic waves by multiple cylinders.

关键词： high-order compact scheme Hybrid cell-edge and cell-node Dissipative Compact Scheme (HDCS) Weighted CompactNonlinear Scheme (WCNS) Complex Geometry Geometric Conservation Law (GCL)

Critical deflagration waves leading to detonation onset under different boundary conditions

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Chinese Physics B 2015年第1期24卷 361-368页

作者：林伟周进范孝华林志勇 Science and Technology on Scramjet Laboratory National University of Defense Technology China Aerodynamics research & development Center

High-speed turbulent critical deflagration waves before detonation onset in H2–air mixture propagated into a square cross section channel, which was assembled of optional rigid rough, rigid smooth, or flexible walls. The corresponding propagation characteristic and the influence of the wall boundaries on the propagation were investigated via high-speed shadowgraph and a high-frequency pressure sampling system. As a comprehensive supplement to the different walls effect investigation, the effect of porous absorbing walls on the detonation propagation was also investigated via smoke foils and the high-frequency pressure sampling system. Results are as follows. In the critical deflagration stage, the leading shock and the closely following turbulent flame front travel at a speed of nearly half the CJ detonation velocity. In the preheated zone, a zonary flame arises from the overlapping part of the boundary layer and the pressure waves, and then merges into the mainstream flame. Among these wall boundary conditions, the rigid rough wall plays a most positive role in the formation of the zonary flame and thus accelerates the transition of the deflagration to detonation（DDT）, which is due to the boost of the boundary layer growth and the pressure wave reflection. Even though the flexible wall is not conducive to the pressure wave reflection, it brings out a faster boundary layer growth, which plays a more significant role in the zonary flame formation. Additionally, the porous absorbing wall absorbs the transverse wave and yields detonation decay and velocity deficit. After the absorbing wall, below some low initial pressure conditions, no re-initiation occurs and the deflagration propagates in critical deflagration for a relatively long distance.

关键词： critical deflagration waves wall boundary condition zonary flame pressure waves

Simulation of wind-induced near-inertial oscillations in a mixed layer near the east coast of Korea in the East/Japan Sea

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Acta Oceanologica Sinica 2013年第9期32卷 11-20页

作者： NAM SungHyun PARK Young-Gyu Naval Systems development Center Agency for Defense Development Ocean Circulation and Climate research Division Korea Institute of Ocean Science and Technology

Using a simple damped slab model, it was possible to show that a local wind induced 88% （15 of 17） of the near-inertial oscillations （NIO） observed in the mixed layer near the east coast of Korea from 1999 to 2004. The model, however, overestimated the energy level in about two-thirds of the simulated cases, because the slab model was forced with winds whose characteristic period was shorter than the damping time scale of the model at 1.5 d. At the observation site, due to typhoons and orographic effects, high-frequency wind forcing is quite common, as is the overestimation of the energy level in the slab model results. In short, a simple slab model with a damping time-scale of about 1.5 d would be enough to show that the local wind was the main energy source of the near-inertial energy in this area, but the model could not be used to accurately estimate the amount of the work done by the wind to the mixed layer.

关键词： near-inertial oscillations near-inertial waves slab model high-frequency wind forcing eastcoast of Korea

Ripple-effect analysis for operational architecture of air defense systems with supernetwork modeling

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Journal of Systems Engineering and Electronics 2014年第2期25卷 249-264页

作者： Zhigang Zou Fuxian Liu Shiman Sun Lu Xia Chengli Fan School of Air and Missile defense Air Force Engineering University research & development Center China Airport Construction Group Corporation

In order to solve the problem that the ripple-effect analy- sis for the operational architecture of air defense systems （OAADS） is hardly described in quantity with previous modeling approaches, a supernetwork modeling approach for the OAADS is put for- ward by extending granular computing. Based on that operational units and links are equal to different information granularities, the supernetwork framework of the OAADS is constructed as a “four- network within two-layer” structure by forming dynamic operating coalitions, and measuring indexes of the ripple-effect analysis for the OAADS are given combining with Laplace spectral radius. In this framework, via analyzing multidimensional attributes which inherit relations between operational units in different granular scales, an extended granular computing is put forward integrating with a topological structure. Then the operation process within the supernetwork framework, including transformation relations be- tween two layers in the vertical view and mapping relations among functional networks in the horizontal view, is studied in quantity. As the application case shows, comparing with previous modeling approaches, the supernetwork model can validate and analyze the operation mechanism in the air defense architecture, and the ripple-effect analysis can be used to confirm the key operational unit with micro and macro viewpoints.

关键词： operational architecture air defense system super-network model Laplace spectral radius ripple-effect analysis.

Accuracy of genomic selection in biparental populations of flax(Linum usitatissimum L.)

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The Crop Journal 2016年第4期4卷 290-303页

作者： Frank M.You Helen M.Booker Scott D.Duguid Gaofeng Jia Sylvie Cloutier Morden research and development Centre Agriculture and Agri-Food Canada Crop development Centre Department of Plant Sciences University of Saskatchewan Ottawa research and development Centre Agriculture and Agri-Food Canada

Flax is an important economic crop for seed oil and stem fiber. Phenotyping of traits such as seed yield, seed quality, stem fiber yield, and quality characteristics is expensive and time consuming. Genomic selection(GS) refers to a breeding approach aimed at selecting preferred individuals based on genomic estimated breeding values predicted by a statistical model based on the relationship between phenotypes and genome-wide genetic markers. We evaluated the prediction accuracy of GS(rMP) and the efficiency of GS relative to phenotypic selection(RE) for three GS models: ridge regression best linear unbiased prediction(RR-BLUP),Bayesian LASSO(BL), and Bayesian ridge regression(BRR), for seed yield, oil content, iodine value, linoleic, and linolenic acid content with a full and a common set of genome-wide simple sequence repeat markers in each of three biparental populations. The three GS models generated similar rMPand RE, while BRR displayed a higher coefficient of determination(R^2)of the fitted models than did RR-BLUP or BL. The mean rMPand RE varied for traits with different heritabilities and was affected by the genetic variation of the traits in the *** for seed yield generated a mean RE of 1.52 across populations and marker sets, a value significantly superior to that for direct phenotypic selection. Our empirical results provide the first validation of GS in flax and demonstrate that GS could increase genetic gain per unit time for linseed breeding. Further studies for selection of training populations and markers are warranted.

关键词： Genomic selection SSR Flax Linseed Seed yield Fatty acid composition

Impacts of NBTI/PBTI on power gated SRAM

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Journal of Central South University 2013年第5期20卷 1298-1306页

作者：黄平邢座程 School of Computer National University of Defense Technology Computational Aerodynamics Institute China Aerodynamics Research and Development Center

A signal probability and activity probability (SPAP) model was proposed firstly, to estimate the impacts of the negative bias temperature instability (NBTI) and positive bias temperature instability (PBTI) on power gated static random access memory (SRAM). The experiment results show that PBTI has significant influence on the read and write operations of SRAM with power gating, and it deteriorates the NBTI effects and results in a up to 39.38% static noise margin reduction and a 35.7% write margin degradation together with NBTI after 106 s working time. Then, a circuit level simulation was used to verify the assumption of the SPAP model, and finally the statistic data of CPU2000 benchmarks show that the proposed model has a reduction of 3.85% for estimation of the SNM degradation after 106 s working time compared with previous work.

关键词： negative bias temperature instability (NBTI) positive bias temperature instability (PBTI) static random access memory(SRAM) power gating

Production systems and important antimicrobial resistant-pathogenic bacteria in poultry:a review

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Journal of Animal Science and Biotechnology 2023年第2期14卷 481-500页

作者： Philip H.W.Mak Muhammad Attiq Rehman Elijah G.Kiarie Edward Topp Moussa S.Diarra Guelph research and development Centre Agriculture and Agri-Food Canada(AAFC)GuelphONCanada Department of Animal Biosciences University of GuelphGuelphONCanada London research and development Center AAFCLondonONCanada.

Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers,despite substantial efforts in prevention and *** have been used not only for the treatment and prevention of such diseases,but also for growth ***,these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans,ani-mals,and the *** break down the antimicrobial resistance(AMR),poultry producers are restricting the antimicrobial use(AMU)while adopting the antibiotic-free(ABF)and organic production practices to satisfy consum-ers’***,it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut *** Gram-negative(Salmonella enterica serovars,Campylobacter jejuni/coli,***)and Gram-positive(Enterococcus spp.,Staphylococcus *** ***)bacteria harboring multiple AMR determinants have been reported in poultry including organically-and ABF-raised *** this review,we discussed major poultry production systems(conventional,ABF and organic)and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportuni-ties to develop efficient and safe production practices in controlling pathogens.

关键词： Antibiotic-free Antimicrobial resistance Conventional feeding Organic Poultry

Effects of bimetallic catalysts on synthesis of nitrogen-doped carbon nanotubes as nanoscale energetic materials

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Particuology 2011年第5期9卷 465-470页

作者： Hao Liu Yong Zhang Ruying Li Xueliang Sun Hakima Abou-Rachid Department of Mechanical and Materials Engineering University of Western Ontario London ON N6A 5B9 Canada defense research ＆ development canada 2459 Boulevard PieXI Nord Quebec QC G3J IX5 Canada

Well aligned nitrogen-doped carbon nanotubes （CNx-NTs）, as energetic materials, are synthesized on a silicon substrate by aerosol-assisted chemical vapor deposition, Tungsten （W） and molybdenum （Mo） metals are respectively introduced to combine with iron （Fe） to act as a bimetallic co-catalyst layer. Cor- relations between the composition and shape of the co-catalyst and morphology, size, growth rate and nitrogen doping amount of the synthesized CNx-NTs are investigated by secondary and backscattered electron imaging in a field emission scanning electron microscope （FESEM） and X-ray photoelectron spectrometer （XPS）. Compared to pure iron catalyst, W-Fe co-catalyst can result in lower growth rate, larger diameter and wider size distribution of the CNx-NTs; while incorporation of molybdenum into the iron catalyst layer can reduce the diameter and size distribution of the nanotubes. Compared to the sole iron catalyst, Fe-W catalyst impedes nitrogen doping while Fe-Mo catalyst promotes the incorporation of nitrogen into the nanotubes. The present work indicates that CNx-NTs with modulated size, growth rate and nitrogen doping concentration are expected to be synthesized by tuning the size and composition of co-catalysts, which may find great potential in producing CNx-NTs with controlled structure and properties,

关键词： Nitrogen doped carbon nanotubes Chemical vapor deposition Bimetallic catalyst

Conductometric Titration for the Prediction of Conductivity in Solutions with Polymeric Membranes

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Journal of Electronic Science and Technology 2017年第4期15卷 342-350页

作者： María José Lavorante Juan Isidro Franco research and development of Renewable Energy Department at CITEDEF Institute of Scientific and Technical Research for the Defense Villa Martelli B1603ALO Argentina

The analytical technique of conductometric titration is used to characterize polymeric *** technique allows obtaining the polymer dry weight capacity(DWC) and the extent of reaction and establishing the optimal number of water molecules per sulfonic *** this particular case the polymer material under study was Nafion?*** different reactions were made: Neutralization and *** of them allow obtaining the same *** titrations could be considered as a good method to study the neutralization and exchange reactions for polymeric materials used in fuel cells or *** implementation of this analytical technique allows reducing operation time of those types of *** waiting time between determinations permits to say that the amount of reactant consumed and products obtained were the same after each addition of titrant.

关键词： Conductivity conductometric titration polymeric membranes