检索结果-南通市图书馆

Computer Modeling in Engineering & Sciences 2021年第4期127卷 273-290页

作者： Zhijian yang Guochang Li yan lang Zengmei Qiu School of Civil Engineering Shenyang Jianzhu UniversityShenyang110168China Department of Building Engineering Suqian CollegeSuqian223800China

This paper studies the contribution of CFRP(carbon fiber-reinforced polymer)to the mechanical behavior of high strength concrete-filled square steel tube(HCFST)under biaxial eccentric *** new type of composite member is composed of an inner CFRP tube and an outer steel tube with concrete filled in the two *** finite element analysis was made by ABAQUS on the behavior of high strength concrete filled square steel tubular columns with inner CFRP circular tube subjected to bi-axial eccentric *** results obtained from the finite element analysis were verified with the experimental *** addition,the load-deflection curves in the whole process were calculated and analyzed,which can be divided into three segments:Elastic phase,plastic phase,descending *** on the load-deflection curves,the stresses analysis on the core concrete,CFRP tube and steel tube were *** confinement effect of the CFRP tube improves the ductility of HCFST-CFRP stub *** ratio and eccentricity affect the ultimate bearing capacity of HCFST stub ***,a calculation formula of ultimate bearing capacity was proposed in the paper.

关键词： CFRP tube concrete-filled square steel tube high strength concrete bi-axial bending stub column

Multi-mode controller IC for soft-switched flyback converter with high efficiency over the entire load range

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1411-1419页

作者： Hai CHEN Meng-lian ZHAO Xiao-bo WU Xiao-lang yan Institute of VLSI Design Zhejiang University Hangzhou 310027 China

This paper presents a multi-mode control scheme for a soft-switched flyback converter to achieve high efficiency and excellent load regulation over the entire load range. At heavy load, critical conduction mode with valley switching (CCMVS) is employed to realize soft switching so as to reduce turn-on loss of power switch as well as conducted electromagnetic interference (EMI). At light load, the converter operates in discontinuous conduction mode (DCM) with valley switching and adaptive off-time control (AOT) to limit the switching frequency range and maintain load regulation. At extremely light load or in standby mode, burst mode operation is adopted to provide low power consumption through reducing both switching frequency and static power dissipation of the controller. The multi-mode control is implemented by an oscillator whose pulse duration is adjusted by output feedback. An accurate valley switching control circuit guarantees the minimum turn-on voltage drop of power switch. The pro-totype of the controller IC was fabricated in a 1.5-μm BiCMOS process and applied to a 310 V/20 V, 90 W flyback DC/DC converter circuitry. Experimental results showed that all expected functions were realized successfully. The flyback converter achieved a high efficiency of over 80% from full load down to 2.5 W, with the maximum reaching 88.8%, while the total power consumption in standby mode was about 300 mW.

关键词： Integrated circuit Multi-mode controller Soft-switched flyback converter Valley detection

High throughput VLSI architecture for H.264/AVC context-based adaptive binary arithmetic coding(CABAC) decoding

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第6期14卷 449-463页

作者： Kai HUANG De MA Rong-jie yan Hai-tong GE Xiao-lang yan Institute of VLSI Design Zhejiang University State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of Sciences Hangzhou C-Sky Micro-System Company

Context-based adaptive binary arithmetic coding(CABAC) is the major entropy-coding algorithm employed in H.264/*** this paper,we present a new VLSI architecture design for an H.264/AVC CABAC decoder,which optimizes both decode decision and decode bypass engines for high throughput,and improves context model allocation for efficient external memory *** on the fact that the most possible symbol(MPS) branch is much simpler than the least possible symbol(LPS) branch,a newly organized decode decision engine consisting of two serially concatenated MPS branches and one LPS branch is proposed to achieve better parallelism at lower timing path cost.A look-ahead context index(ctxIdx) calculation mechanism is designed to provide the context model for the second MPS branch.A head-zero detector is proposed to improve the performance of the decode bypass engine according to UEGk encoding *** addition,to lower the frequency of memory access,we reorganize the context models in external memory and use three circular buffers to cache the context models,neighboring information,and bit stream,respectively.A pre-fetching mechanism with a prediction scheme is adopted to load the corresponding content to a circular buffer to hide external memory *** results show that our design can operate at 250 MHz with a 20.71k gate count in SMIC18 silicon technology,and that it achieves an average data decoding rate of 1.5 bins/cycle.

关键词： H.264/AVC Context-based adaptive binary arithmetic coding(CABAC) Decoder VLSI

A parallel memory architecture for video coding

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1644-1655页

作者： Jian-ying PENG Xiao-lang yan De-xian LI Li-zhong CHEN Institute of VLSI Design Zhejiang University Hangzhou 310027 China

To efficiently exploit the performance of single instruction multiple data （SIMD） architectures for video coding, a parallel memory architecture with power-of-two memory modules is proposed. It employs two novel skewing schemes to provide conflict-free access to adjacent elements （8-bit and 16-bit data types） or with power-of-two intervals in both horizontal and vertical directions, which were not possible in previous parallel memory architectures. Area consumptions and delay estimations are given respectively with 4, 8 and 16 memory modules. Under a 0.18-pm CMOS technology, the synthesis results show that the proposed system can achieve 230 MHz clock frequency with 16 memory modules at the cost of 19k gates when read and write latencies are 3 and 2 clock cycles, respectively. We implement the proposed parallel memory architecture on a video signal processor （VSP）. The results show that VSP enhanced with the proposed architecture achieves 1.28× speedups for H.264 real-time decoding.

关键词： Single instruction multiple data (SIMD) Video coding Parallel memory Skewing scheme

Regularized level-set-based inverse lithography algorithm for IC mask synthesis

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第10期14卷 799-807页

作者： Zhen GENG Zheng SHI Xiao-lang yan Kai-sheng LUO Institute of VLSI Design Zhejiang University

Inverse lithography technology(ILT)is one of the promising resolution enhancement techniques,as the advanced IC technology nodes still use the 193 nm light *** ILT,optical proximity correction(OPC)is treated as an inverse imaging problem to find the optimal solution using a set of mathematical *** all the algorithms for ILT,the level-set-based ILT(LSB-ILT)is a feasible choice with good production in ***,the manufacturability of the optimized mask is one of the critical issues in ILT;that is,the topology of its result is usually too complicated to *** put forward a new algorithm with high pattern fidelity called regularized LSB-ILT implemented in partially coherent illumination(PCI),which has the advantage of reducing mask complexity by suppressing the isolated irregular holes and protrusions in the edges generated in the optimization process.A new regularization term named the Laplacian term is also proposed in the regularized LSB-ILT optimization process to further reduce mask complexity in contrast with the total variation(TV)*** results show that the new algorithm with the Laplacian term can reduce the complexity of mask by over 40%compared with the ordinary LSB-ILT.

关键词： Inverse lithography technology Complexity Level set Regularization

SVM based layout retargeting for fast and regularized inverse lithography

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第5期15卷 390-400页

作者： Kai-sheng LUO Zheng SHI Xiao-lang yan Zhen GENG Institute of VLSI Design Zhejiang University

Inverse lithography technology(ILT),also known as pixel-based optical proximity correction(PB-OPC),has shown promising capability in pushing the current 193 nm lithography to its *** treating the mask optimization process as an inverse problem in lithography,ILT provides a more complete exploration of the solution space and better pattern fidelity than the traditional edge-based ***,the existing methods of ILT are extremely time-consuming due to the slow convergence of the optimization *** address this issue,in this paper we propose a support vector machine(SVM)based layout retargeting method for ILT,which is designed to generate a good initial input mask for the optimization process and promote the convergence *** by optimized masks of training layouts generated by conventional ILT,SVM models are learned and used to predict the initial pixel values in the‘undefined areas’of the new *** this process,an initial input mask close to the final optimized mask of the new layout is generated,which reduces iterations needed in the following optimization *** is another critical issue in ILT;however,the mask generated by our layout retargeting method is quite irregular due to the prediction inaccuracy of the SVM *** compensate for this drawback,a spatial filter is employed to regularize the retargeted mask for complexity *** implemented our layout retargeting method with a regularized level-set based ILT(LSB-ILT)algorithm under partially coherent illumination *** results show that with an initial input mask generated by our layout retargeting method,the number of iterations needed in the optimization process and runtime of the whole process in ILT are reduced by 70.8%and 69.0%,respectively.

关键词： Inverse lithography technology Optical proximity correction Layout retargeting Support vector machine

Efficient implementation of a cubic-convolution based image scaling engine

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第9期12卷 743-753页

作者： Xiang WANG Yong DING Ming-yu LIU Xiao-lang yan Institute of VLSI Design Zhejiang University Hangzhou 310027 China

In video applications, real-time image scaling techniques are often required. In this paper, an efficient implementation of a scaling engine based on 4×4 cubic convolution is proposed. The cubic convolution has a better performance than other traditional interpolation kernels and can also be realized on hardware. The engine is designed to perform arbitrary scaling ratios with an image resolution smaller than 2560× 1920 pixels and can scale up or down, in horizontal or vertical direction. It is composed of four fimctional units and five line buffers, which makes it more competitive than conventional architectures. A strict fixed-point strategy is applied to minimize the quantization errors of hardware realization. Experimental results show that the engine provides a better image quality and a comparatively lower hardware cost than reference implementations.

关键词： Cubic-convolution Hardware implementation Interpolation Engine

A sparse matrix model-based optical proximity correction algorithm with model-based mapping between segments and control sites

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 436-442页

作者： Bin LIN Xiao-lang yan Zheng SHI Yi-wei yanG Institute of VLSI Design Zhejiang University Hangzhou 310027 China

Optical proximity correction (OPC) is a key step in modern integrated circuit (IC) *** quality of model-based OPC (MB-OPC) is directly determined by segment offsets after OPC ***,in conventional MB-OPC,the intensity of a control site is adjusted only by the movement of its corresponding segment;this scheme is no longer accurate enough as the lithography process *** the other hand,matrix MB-OPC is too time-consuming to become *** this paper,we propose a new sparse matrix MB-OPC algorithm with model-based mapping between segments and control *** put forward the concept of 'sensitive area'.When the Jacobian matrix used in the matrix MB-OPC is evaluated,only the elements that correspond to the segments in the sensitive area of every control site need to be calculated,while the others can be set to *** new algorithm can effectively improve the sparsity of the Jacobian matrix,and hence reduce the *** theoretical analysis and experiments show that the sparse matrix MB-OPC with model-based mapping is more accurate than conventional MB-OPC,and much faster than matrix MB-OPC while maintaining high accuracy.

关键词： Matrix sparsity Optical proximity correction (OPC) Convergence Segment Sensitive area

Discrete-time charge analysis for a digital RF charge sampling mixer

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 307-314页

作者： Yun PAN Ning GE Xiao-lang yan Xiao-peng YU Institute of VLS1 Design Zhejiang University Hangzhou 310027 China Department of Electronic Engineering Tsinghua University Beijing 100084 China

This paper presents an approach for analyzing the key parts of a general digital radio frequency(RF) charge sampling mixer based on discrete-time charge *** cascade sampling and filtering stages are analyzed and expressed in theoretical *** effects of a pseudo-differential structure and CMOS switch-on resistances on the transfer function are addressed in *** DC-gain is restrained by using the pseudo-differential *** transfer gain is reduced because of the charge-sharing time constant when taking CMOS switch-on resistances into *** unfolded transfer gains of a typical digital RF charge sampling mixer are analyzed in different cases using this approach.A circuit-level model of the typical mixer is then constructed and simulated in Cadence SpectreRF to verify the *** work informs the design of charge-sampling,infinite impulse response(ⅡR) filtering,and finite impulse response(FIR) filtering *** discrete-time approach can also be applied to other multi-rate receiver systems based on charge sampling techniques.

关键词： Digital RF Charge sampling Discrete-time Pseudo-differential Switch-on resistance

Synergistic roles of LAX1 and FZP in the development of rice sterile lemma

在线全文

学校读者我要写书评

暂无评论

The Crop Journal 2020年第1期8卷 16-25页

作者： Yidong Wang Shanshan Wei Yubing He lang yan Rongchen Wang Yunde Zhao aNational Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research(Wuhan)Huazhong Agricultural UniversityWuhan 430070HubeiChina College of Life Science and Technology Huazhong Agricultural UniversityWuhan 430070HubeiChina Section of Cell and Developmental Biology University of California San DiegoLa JollaCA 92093-0116USA

Rice florets are subtended by two sterile lemmas,whose origin and biological functions have not been studied *** we demonstrate that two putative transcription factors,LAX PANICLE1(LAX1)and FRIZZY PANICLE(FZP),synergistically control the development of sterile *** LAX1 and FZP are previously known for their roles in panicle and floret *** of either LAX1 or FZP greatly reduces the number of floret *** generated new lax1 mutants(lax1-c)using CRISPR/Cas9 gene editing *** addition to the expected lax panicle phenotypes,we noticed that a significant number of spikelets of lax1-c developed elongated sterile ***,our characterization of lax1-RNAi plants also revealed sterile lemma phenotypes similar to lax1-c *** isolated a weak allele of fzp(fzp-14)in a genetic screen for lax1–1 *** fzp-14 lax1–1 double mutants completely eliminated flower ***,the isolated fzp-14 produced spikelets with elongated sterile ***,fzp-14 was haploid-insufficient in the lax1–1 background whereas fzp-14 heterozygous plants were indistinguishable from wild type *** lax1–1 fzp-14+/−also developed elongated sterile lemma as observed in lax1-c,lax1-RNAi,and fzp-14,suggesting that LAX1 and FZP synergistically control sterile lemma development.

关键词： LAX1 FZP Rice CRISPR Flower development Sterile lemma