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Design and verification of an FPGA programmable logic element based on Sense-Switch pFLASH

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Frontiers of information Technology & Electronic engineering 2024年第4期25卷 485-499页

作者： zhengzhou CAO Guozhu LIU Yanfei ZHANG Yueer SHAN Yuting XU No.58 Research Institute China Electronics Technology Group CorporationWuxi 214035China

This paper proposes a kind of programmable logic element(PLE)based on Sense-Switch pFLASH *** programming Sense-Switch pFLASH,all three-bit look-up table(LUT3)functions,partial four-bit look-up table(LUT4)functions,latch functions,and d flip flop(DFF)with enable and reset functions can be *** PLE uses a choice of operational logic(COOL)approach for the operation of logic functions,it allows any logic circuit to be implemented at any ratio of combinatorial logic to *** intrinsic property makes it close to the basic application specific integrated circuit(ASIC)cell in terms of fine granularity,thus allowing ASIC-like cell-based mappers to apply all their optimization *** measuring Sense-Switch pFLASH and PLE circuits,the results show that the“on”state driving current of the Sense-Switch pFLASH is about 2.5.52.A,and that the“off”state leakage current is about 0.1 *** programmable function of PLE works *** delay of the typical combinatorial logic operation AND3 is 0.69 ns,and the delay of the sequential logic operation DFF is 0.65 ns,both of which meet the requirements of the design technical index.

关键词： Field programmable gate array(FPGA) Programmable logic element(PLE) Boolean logic operation Look-up table Sense-Switch pFLASH Threshold voltage

Fracture analysis of a functionally graded interfacial zone between two dissimilar homogeneous materials

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Science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 540-552页

作者： CHENG Zhanqi1,2.& ZHONG Zheng1 1. School of Aerospace engineering and Applied mechanics, Tongji university, Shanghai 2.0092. China 2. College of Civil engineering, zhengzhou university, zhengzhou 450002. China School of Aerospace engineering and Applied mechanics Tongji University Shanghai China College of Civil engineering Zhengzhou University Zhengzhou China

In this paper the plane elasticity problem for a functionally graded interfacial zone containing a crack between two dissimilar homogeneous materials has been considered. It is assumed that in the interfacial zone the reciprocal of the shear modulus is a linear function of the coordinate, while Possion’s ratio keeps constant. By utilizing the Fourier transformation technique and the transfer matrix method, the mixed boundary problem is reduced to a system of singular integral equations that are solved numerically. The influences of the geometric parameters and the graded parameter on the stress intensity factors are investigated. The numerical results show that the graded parameters, the thickness of interfacial zone, the crack size and location have significant effects on the stress intensity factors.

关键词： functionally graded material interfacial zone fracture stress intensity factor

A fingerprint feature extraction algorithm based on curvature of Bezier curve

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Progress in Natural Science:Materials International 2007年第11期17卷 1376-1381页

作者： Yuan Huaqiang1, Ye Yangdong2. Deng Jianguang2. Chai Xiaoguang1 and Li Yong1(1. School of Software, Dongguan university of Technology, Dongguan 52.808, China 2. information {2. Institute, zhengzhou university, zhengzhou 450001, China) School of Software Dongguan University of Technology Dongguan 523808 China information engineering Institute Zhengzhou University Zhengzhou 450001 China

Fingerprint feature extraction is a key step of fingerprint identification. A novel feature extraction algorithm is proposed in this paper, which describes fingerprint feature with the bending information of fingerprint ridges. Ridges in the specific region of fingerprint images are traced firstly in the algorithm, and then these ridges are fit with Bezier curve. Finally, the point that has the maximal curvature on Bezier curve is defined as a feature point. Experimental results demonstrate that this kind of feature points characterize the bending trend of fingerprint ridges effectively, and they are robust to noise, in addition, the extraction precision of this algorithm is also better than the conventional approaches.

关键词： fingerprint identification feature extraction Bezier curve curvature

Effects of Al on Microstructure and High-Temperature Wear Properties of Austenitic Heat-Resistant Steel

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Journal of Iron and Steel Research International 2012年第3期19卷 62-66页

作者： ZHANG Yan1, SUN Yu-fu2. ZHAO Jing-yu2. GUAN Shao-kang2.(1. School of Materials engineering, Nanjing Institute of Technology, Nanjing 2.1167, Jiangsu, China 2. School of Materials Science and engineering, {2. university, {2. 450002. Henan, China) School of Materials engineering Nanjing Institute of Technology Nanjing Jiangsu China School of Materials Science and engineering Zhengzhou University Zhengzhou Henan China

Microstructure and high-temperature dry sliding wear at 600 ~C in ambient air of austenitic heat-resistant steel ZG40Cr2.Ni2. with different contents （mass percent） of AI （0 to 7.10~） have been investigated. The results show that microstructures of 4.68% and 7.10% A1 addition content consist of the matrix and reinforcement of inter- metallic compound y＇ and carbide, while microstructures of ZG40Cr2.Ni2. without A1 and with A1 of 1.68% are ab- sent of y＇. Higher wear resistance than the original ZG40Cr2.Ni2. alloy is achieved in alloys with higher content of A1 under the same high-temperature wear test condition. The wear rates of Fe-2.Cr-2.Ni-7.10A1 and Fe-2.Cr-2.Ni- 4.68A1 are only 2..83% and 45.83% of that of Fe-2.Cr-2.Ni, respectively. Heat-resistant steels with higher con- tents of AI （4.72. and 7.10%） have higher hardness than those with lower contents of AI （1.68% and 0）. Wear mechanisms of ZG40Cr2.Ni2. are considered as severe plough plastic deformation and slight adhesive. However, wear mechanisms of Fe-2.Cr-2.Ni 4.68A1 are light micro-cutting and oxidation-wear, while that of Fe-2.Cr-2.Ni- 7. 10A1 are severe adhesive transfer and oxidation-wear_

关键词： austenitic heat resistant steel Al microstructure high-temperature sliding wear mechanism

Local and Global Character Sums

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Acta Mathematica Sinica,English Series 2000年第3期16卷 535-540页

作者： Chunlei Liu zhengzhou university of {2. engineering,zhengzhou 450002.P.R.China zhengzhou university of {2. engineering Zhengzhou 450002 P. R. China

Hua’s estimate is established for character sums in a number field.A relationship between liftings of a character sum in a local field is also studied.

关键词： Character sum Exponential sum

Dynamic Properties of Concrete under Severe Environmental Condition

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Journal of Wuhan university of Technology(Materials Science) 2010年第5期25卷 877-882页

作者：闫东明 Department of Hydraulic and Environmental engineering Zhengzhou University Department of Civil and Hydraulic engineering Dalian University of Technology

Exposure to environmental conditions can significantly influence the mechanical behavior of concrete structures in civil engineering. In this study, the effect of environmental factors, such as moisture and temperature, on the strain-rate sensitivity of concrete mixtures was systematically investigated. The strain rate varied from 10^-5s^-1 to 10^-2.^-1. From the investigation it was concluded that moisture content had a significant influence on the strain-rate sensitivity of concrete. With regard to concrete with low moisture content, temperature had little influence on the rate-dependent behavior; while for fully saturated specimens, a significant influence was observed. These phenomena were attributed to the meso-scale bonding properties of the concrete matrix. Equations were derived to characterize the ultimate strength increment of concrete with strain rate under different environmental conditions. An explanation to the dynamic failure mechanisms of concrete based on the experimental findings was proposed.

关键词： concrete strain rate moisture content temperature failure mechanism

Tribological Properties of SiC/Cu Composite at High Temperature

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Journal of Wuhan university of Technology(Materials Science) 2009年第6期24卷 888-891页

作者：范冰冰张锐 zhengzhou Institute of Aeronautical Industry Management School of Materials Science & engineering Zhengzhou University

SiC/Cu composites were prepared by hot pressing. The high temperature tribological properties of the composites were investigated. XRD, SEM techniques were carried out to characterize the samples. It is found that the friction coefficient of SiC/Cu composites increases with the increasing SiC content. The SiC reinforcement particles are worn down other than removed by pulling out during the wear test. Oxidation of Cu debris leads to the smooth contacting surface. Ring crack is formed under the cyclic wear test. The crack propagates through the damaged matrix and along the brittle interface between SiC particles and Cu matrix.

关键词： SiC/Cu composite tribological properties high temperature wear ring crack

A new approach based on PSO algorithm to find good computational encoding sequences

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Progress in Natural Science:Materials International 2007年第6期17卷 712-716页

作者： Cui Guangzhao1, Niu Yunyun1, Wang Yanfeng1, Zhang Xuncai2.and Pan Linqiang2.1. School of Electrical and Electronic engineering, zhengzhou {2. of Light Industry, zhengzhou 450002. China 2. Research Institute of Biomolecular Computer, Huazhong {2. of Science and Technology, Wuhan 430074, China) School of Electrical and Electronic engineering Zhengzhou University of Light Industry Zhengzhou 450002 China Research Institute of Biomolecular Computer Huazhong University of Science and Technology Wuhan 430074 China

Computational encoding DNA sequence design is one of the most important steps in molecular computation. A lot of research work has been done to design reliable sequence library. A revised method based on the support system developed by Tanaka et al. is proposed here with different criteria to construct fitness function. Then we adapt particle swarm optimization (PSO) algorithm to our encoding problem. By using the new algorithm, a set of sequences with good quality is generated. The result also shows that our PSO-based approach could rapidly converge at the minimum level for an output of the simulation model. The celerity of the algorithm fits our requirements.

关键词： DNA computing computational encoding DNA sequences PSO algorithm fitness function

SYNTHESIS AND CHARACTERIZATION OF ORGANOMONTMORILLONITE AND POLYAMIDE 66/MONTMORILLONITE NANOCOMPOSITES

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Chinese Journal of Polymer Science 2002年第6期20卷 551-557页

作者： Cheng-shen Zhu Xin Kang Su-qin He Liu-yang Wang Li-yun Lu College of Materials engineering,zhengzhou {2., zhengzhou 450052. China College of Materials engineering Zhengzhou University Zhengzhou 450052

The montmorillonites (MMTs), layered, smectite-type silicates, were premodified by two different methods prior to the polymer melt intercalation. In one case MMTs were modified with cetyltrimethylammonium bromide (CTAB), and termed as organomontmorillonites (OMMTs); in the other case MMTs were modified by nylon, and the products were called modified montmorillonites (MMMTs). The effects of CTAB and nylon on the MMTs were investigated by using TG and WAXD. The results show that interlayer spacings of CTAB and nylon modified MMTs are larger than that of sodium MMTs. Then, polyamide 66 (PA 66)/MMT nanocomposites were obtained through the method of melt intercalation of polymers. The nanocomposites were characterized by WAXD, TEM and Molau experiments. The results indicate that the MMTs disperse homogeneously in the PA 66 matrix. The mechanical properties of nanocomposites, such as tensile properties and flexural properties, were also measured and show a tendency to increase with increase of MMT content and reach the maximum values at 5phr MMT content. The heat distortion temperature (HDT) of the nanocomposites (7 phr) is about 32.K higher than that of pure PA 66.

关键词： montmorillonite polyamide 66 nanocomposites melt intercalation