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An efficient hardware design for HDTV H.264/AVC encoder

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第6期12卷 499-506页

作者： liang wei Institute of Information and Communication Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 31002 7 China

This paper presents a hardware efficient high definition television (HDTV) encoder for H.264/AVC. We use a two-level mode decision (MD) mechanism to reduce the complexity and maintain the performance, and design a sharable architecture for normal mode fractional motion estimation (NFME), special mode fractional motion estimation (SFME), and luma motion compensation (LMC), to decrease the hardware cost. Based on these technologies, we adopt a four-stage macro-block pipeline scheme using an efficient memory management strategy for the system, which greatly reduces on-chip memory and bandwidth requirements. The proposed encoder uses about 1126k gates with an average Bjontegaard-Delta peak signal-to-noise ratio (BD-PSNR) decrease of 0.5 dB, compared with JM15.0. It can fully satisfy the real-time video encoding for 1080p@30 frames/s of H.264/AVC high profile.

关键词： H.264/AVC High-definition television (HDTV) Hardware Architecture Encoder

Syntheses of α-Hydroxyarylacetic Acids in the Presence of Different Phase Transfer Catalysts Under Sonication

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Chemical Research in Chinese Universities 2001年第2期17卷 175-177页

作者： XU wei-liang Zhejiang Univ Organ Chem Grp Huajiachi Sect Hangzhou 310029 Peoples R China

The syntheses of α-hydroxyarylacetic acids with a good yield in the presence of different phase transfer catalysts (PTC) under sonication were studied. The results obtained are superior to those by other similar methods. The data show that β-cyclodextrin (β-CD) is more efficient than other PTC. The preliminary reaction conditions are also discussed.

关键词： α-Hydroxyarylacetic acid Phase transfer catalyst Sonication

Micromagnetic simulation of FeCo write head in perpendicular recording hard disk drives

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Rare Metals 2006年第z1期25卷 502-508页

作者： QUAN liang wei Dan Lab of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China Lab of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

The single-pole tip (SPT) heads made of the high saturation FeCo ferromagnetic metals are crucial for the actualization of ultrahigh density perpendicular recording. The effective head field distribution in the medium is of key importance for the design of the SPT head, which would be analyzed by micromagnetic simulations in this work. Two 3D micromagnetic models of the SPT head were established to select a more appropriate method of modeling, with a magnetostatic image effect or a real soft magnetic material to model the image of the SPT head in soft under layer (SUL). The results from these two designs were tested and compared to the ideal head field calculated by the Jacobi finite element method (FEM); and the design with the real soft magnetic material as image was proved suitable for simulating the ultrahigh density perpendicular recording write head.

关键词： SPT head perpendicular recording micromagnetic simulation image

Nest decoration:Black feathers prevent Crested Mynas from nest usurpation

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Avian Research 2024年第2期15卷 292-297页

作者： Jinmei Liu wei liang Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou571158China

Nests are important structures for birds to raise their offspring and for *** birds incorporate feathers into the nest,since feathers were traditionally thought to serve the function of *** in recent years have considered that some birds place feathers in conspicuous locations in the nest for decoration to trigger a fear response in the *** this study,we investigated whether decorative feathers could deter nest usurpation by Crested Mynas(Acridotheres cristatellus)by manipulating nest box *** results revealed that Crested Mynas preferred black feathers to white feathers as decorations and occupied nest boxes decorated with black feathers significantly less than those decorated with white feathers,suggesting that black decorative feathers in the nest could be more effective in preventing nest usurpation by Crested Mynas and that white decorative feathers may have other *** black feathers in the nest are prominently placed at the edge of the nest to convey the message that“this nest is occupied”or“the owner of this nest has been preyed upon”to visitor Crested Mynas,thus effectively preventing them from usurping the nest at a later stage.

关键词： Extended phenotype Feathers Nest decoration Nest usurpation

Egg rejection and egg recognition mechanisms in Oriental Reed Warblers

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Avian Research 2021年第4期12卷 638-644页

作者： Laikun Ma wei liang Department of Biology and Food Science Hebei Normal University for NationalitiesChengde 067000China Ministry of Education Key Labora-tory for Ecology of Tropical Islands College of Life SciencesHainan Normal UniversityHaikou 571158China Hebei Key Laboratory of Wetland Ecology and Conservation Hengshui UniversityHengshui 053000China

Background:Nest parasitism by cuckoos(Cuculus spp.)results in enormous reproductive failure and forces hosts to evolve antiparasitic strategies,i.e.,recognition of own eggs and rejection of cuckoo *** are often sexual conflicts between male and female individuals in the expression of antiparasitic behavior due to the differences in reproductive inputs and division of ***:By adding a foreign egg made of blue soft clay to the host nest during early incubation period in the field,and by removing several host eggs and adding experimental eggs to control the proportion of two egg types in the nest,we examined egg rejection ability,egg recognition mechanism and sexual difference in egg rejection of the Oriental Reed Warbler(Acrocephalus orientalis),one of the major hosts of Common Cuckoos(Cuculus canorus).Results:Our results indicated that Oriental Reed Warblers can recognize and reject nearly 100%(73/75)of the nonmimetic eggs made of blue soft clay,and they could reject foreign eggs with 100%accuracy,regardless of the ratio of experimental eggs and its own eggs in the ***,all cases of egg rejections recorded by videos were only carried out by ***:Oriental Reed Warblers have a high egg recognition ability and show a true recognition *** female warblers perform egg rejection,suggesting that the sex for host egg incubation seems to play an important role in the evolution of egg recognition mechanisms.

关键词： Cuckoo parasitism Discordancy Egg recognition mechanism Egg rejection True recognition

Removal and transformation of dissolved organic matter in secondary effluent during granular activated carbon treatment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 994-1003页

作者： liang-liang wei Qing-liang ZHAO Shuang XUE Ting JIA State Key Laboratory of Urban Water Resources and Environments （SKL UWRE） School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

This paper focused on the removal and transformation of the dissolved organic matter （DOM） in secondary effluent during the granular activated carbon （GAC） treatment. Using XAD-8/XAD-4 resins, DOM was fractionated into five classes： hydrophobic acid （HPO-A）, hydrophobic neutral （HPO-N）, transphilic acid （TPI-A）, transphilic neutral （TPI-N） and hydrophilic fraction （HPI）. Subsequently, the water quality parameters of dissolved organic carbon （DOC）, absorbance of ultraviolet light at 254 nm （UV-254）, specific ultraviolet light absorbance （SUVA） and trihalomethane formation potential （THMFP） were analyzed for the unfractionated and fractionated water samples. The results showed that the order of the DOC removal with respect to DOM fractions was observed to be HPI〉HPO-A〉HPO-N〉TPI-A〉TPI-N. During the GAC treatment, the THMFP of the unfractionated water samples decreased from 397.4 μg/L to 176.5 μg/L, resulting in a removal efficiency of 55.6%. The removal order of the trilaalomethanes （THMs） precursor was as follows： HPO-A〉TPI-A〉TPI-N〉HPO-N〉HPI. By the GAC treatment, the specific THMFP of HPO-A, TPI-A, TPI-N and the original unfractionated water samples had a noticeable decrease, while that of HPO-N and HPI showed a converse trend. The Fourier transform infrared （FTIR） results showed that the hydroxide groups, carboxylic acids, aliphatic C-H were significantly reduced by GAC treatment.

关键词： Dissolved organic matter (DOM) Fractionation Trihalomethane formation potential (THMFP) Specific THMFP Fourier-transform infrared (FTIR)

Aviation multi-station collaborative detecting based on time-frequency correlation of data-link

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Journal of Systems Engineering and Electronics 2017年第5期28卷 827-840页

作者： Bo Wang Xiaolong liang liang wei Pingni Liu Air Traffic Control and Navigation College Air Force Engineering University Equipment Management and Safety Engineering College Air Force Engineering University

As an important application research topic of the intelligent aviation multi-station, collaborative detecting must overcome the problem of scouting measurement with status of 'fragmentation', and the NP-hardness problem of matching association between target and measurement in the process of scouting to data-link, which has complicated technical architecture of network construction. In this paper, taking advantage of cooperation mechanism on signal level in the aviation multi-station sympathetic network, a method of obtaining target time difference of arrival (TDOA) measurement using multi-station collaborative detecting based on time-frequency association is proposed. The method can not only achieve matching between target and its measurement, but also obtain TDOA measurement by further evolutionary transaction through refreshing sequential pulse time of arrival (TOA) measurement matrix for matching and correlating. Simulation results show that the accuracy of TDOA measurement has significant superiority over TOA, and detection probability of false TDOA measurement introduced by noise and fake measurement can be reduced effectively.

关键词： data-link time-frequency correlation aviation multistation synergistic detection time difference of arrival (TDOA)

Fire's effect on chloride ingress related durability of concrete structure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 675-681页

作者： JIN wei-liang ZHANG Yi Structural Engineering Institute Zhejiang University Hangzhou 310027 China

This paper describes the effects of fire on durability of reinforced concrete structures, and points out that fire not only damages the chemical composition and physical structure of concrete by high temperature, but also leads to an additional risk due to the generation of polyvinyl chloride (PVC) combustion gases. A mathematical model is proposed to calculate chloride ingress profiles in fire damaged concrete, so as to explore the service life prediction of the structure. Rapid Chloride Migration (RCM) test was carried out to determine the chloride diffusion coefficients for the application of the mathematical model. Finally, the detected results of a reported case testified to the validity of the mathematical model.

关键词： Fire High temperature Polyvinyl chloride (PVC) Mathematical model Rapid Chloride Migration (RCM)

Corner strength enhancement of high strength cold-formed steel at normal room and elevated temperatures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1251-1257页

作者： Ju CHEN wei-liang JIN Department of Civil Engineering Zhejiang University Hangzhou 310027 China

In this study, the suitability of current design methods for the 0.2% proof yield strength of the comer regions for high strength cold-formed steel at normal room temperature was investigated. The current standard predictions are generally accurate for outer comer specimen but conservative for inner comer specimen. Based on the experimental results, an analytical model to predict the comer strength of high strength cold-formed steel at normal room temperature was also proposed. The comparison indicated that the proposed model predicted well the comer strength of high strength cold-formed steel not only at normal room temperature but also at elevated temperatures. It is shown that the predictions obtained from the proposed model agree well with the test results. Generally the comer strength enhancement of high strength cold-formed steel decreases when the temperature increases.

关键词： Cold-formed steel Comer Elevated temperatures High strength steel Yield strength