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Commuting Dual Toeplitz Operators on the Orthogonal Complement of the Dirichlet Space

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Acta Mathematica Sinica,English Series 2009年第2期25卷 245-252页

作者： tao YU Shi yue WU Department of Mathematics Zhejiang Normal University Jinhua 321004 P. R. China

In this paper we characterize commuting dual Toeplitz operators with harmonic symbols on the orthogonal complement of the Dirichlet space in the Sobolev space. We also obtain the sufficient and necessary conditions for the product of two dual Toeplitz operators with harmonic symbols to be a finite rank perturbation of a dual Toeplitz operator.

关键词： Sobolev space Dirichlet space dual Toeplitz operator

EXPERIMENTAL STUDY OF CONDENSATION HEAT TRANSFER CHA- RACTERISTICS OF HORIZONTAL TUBE BUNDLES IN VACUUM STATES

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Journal of Hydrodynamics 2012年第4期24卷 628-634页

作者： CHENG Shen SUN Feng-zhong SHI yue-tao School of Energy Source and Power Engineering Shandong UniversityJinan 250061China

TO develop an excellent heat transfer element under the vacuum condition, experiments about the heat transfer performance of horizontal tube bundles of different materials under various vacuum conditions were carried out, including the stainless steel tube, the brass tube, the Ni-based implanted steel tube and the ion implanted brass tube. The relative trends show that the condensation heat transfer coefficient and the overall heat transfer coefficient of bundles of four materials all increase with the vacuum degree, especially, those of the Ni-based implanted steel tube and the ion implanted brass tube. Under a high vacuum condition （0.07 MPa）, the condensation heat transfer coefficient of the Ni-based implanted steel tube bundle is about 1.4 times of that of the stainless steel tube bundle, the condensation heat transfer coefficient of the ion implanted brass tube bundle is found to be about 1.3 times of that of the common brass tube bundle. Therefore, according to the condensation heat transfer characteristics studied under high vacuum conditions, it is believed that a dropwise condensation is partly achieved on the surface of these two implanted tube bundles, and the ion implantation is shown to be an effective method to achieve the dropwise condensation. Based on this study, it is believed that the Ni-based steel tube may replace the brass tube, which is more expensive as a heat transfer component.

关键词： vacuum heat transfer characteristics condensation heat transfer coefficient dropwise condensation

The role of prior in image based 3D modeling： a survey

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Frontiers of Computer Science 2017年第2期11卷 175-191页

作者： Hao ZHU Yongming NIE tao yue Xun CAO Lab for Computational Imaging Technology and Engineering School of Electronic Science and Engineering Nanjing University Nanjing 210023 China

The prior knowledge is the significant supple- ment to image-based 3D modeling algorithms for refining the fragile consistency-based stereo. In this paper, we review the image-based 3D modeling problem according to prior cate- gories, i.e., classical priors and specific priors. The classical priors including smoothness, silhouette and illumination are well studied for improving the accuracy and robustness of the 3D reconstruction. In recent years, various specific priors which take advantage of Manhattan rule, geometry template and trained category features have been proposed to enhance the modeling performance. The advantages and limitations of both kinds of priors are discussed and evaluated in the paper. Finally, we discuss the trend and challenges of the prior studies in the future.

关键词： prior information consistency-based stereo,smoothness illumination silhouette specific prior

Dynamic subcarrier and power allocation based on cooperative game theory in symmetric cooperative OFDMA networks

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 9-16页

作者： LIU Wei LUO tao yue Guang-xin Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In order to improve the efficiency and fairness of radio resource utilization,a scheme of dynamic cooperative subcarrier and power allocation based on Nash bargaining solution（NBS-DCSPA） is proposed in the uplink of a three-node symmetric cooperative orthogonal frequency division multiple access（OFDMA） *** the proposed NBS-DCSPA scheme,resource allocation problem is formulated as a two-person subcarrier and power allocation bargaining game（SPABG） to maximize the system utility,under the constraints of each user＇s maximal power and minimal rate,while considering the fairness between the two ***,the equivalent direct channel gain of the relay link is introduced to decide the transmission mode of each ***,all subcarriers can be dynamically allocated to the two users in terms of their selected transmission *** that,the adaptive power allocation scheme combined with dynamic subcarrier allocation is optimized according to ***,computer simulation is conducted to show the efficiency and fairness performance of the proposed NBS-DCSPA scheme.

关键词： cooperative relay OFDMA radio resource allocation NBS fairness

Ammonium Effects on Nitrate Uptake by Roots of Upland and Paddy Rice Seedlings Related to Membrane Potential Differences

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Agricultural Sciences in China 2010年第6期9卷 799-805页

作者： WANG Xiao-li WANG Yu-qian tao yue-yue FENG Ke College of Environmental Science and Engineering Yangzhou University Yangzhou 225009 P.R. China

Nitrate uptake characteristics and ammonium effects on nitrate uptake were compared between upland rice （Brazilian upland rice） and paddy rice （Wuyujing 3 and Yangdao 6） through the glass microelectrode technique and the concentration gradient method of uptake *** indicated that nitrate uptake by rice seedlings and ammonium effects were depending on membrane potential of root *** upland rice and paddy rice presented obviously different *** all cultivars,the nitrate treatments induced rapid depolarization and then slow repolarization of membrane potential in root epidermal cells,and even hyperpolarization was observed when nitrate concentration was *** membrane potential of epidermal cells in Brazilian upland rice roots was larger and its response to NO3- was bigger than those of two paddy rice *** of membrane potential was amplified when ammonium was simultaneously added with nitrate into the measure medium,but repolarization was reduced,even *** upland rice seedlings had high Vmax of nitrate uptake and low Km,furthermore,Vmax and Km were little affected by ammonium,but Vmax of Wuyujing 3 was reduced ***,inhibition of NH4＋ differed obviously between upland rice and paddy rice.

关键词： nitrate uptake membrane potential ammonium upland rice paddy rice

Effects of SO2 and H2O on low-temperature NO conversion over F-V2O5-WO3/TiO2 catalysts

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Journal of Environmental Sciences 2020年第4期32卷 253-261页

作者： Quanming Liang Jian Li Hong He tao yue Li Tong Beijing Municipal Institute of Labor Protection Beijing Academy of Science and TechnologyBeijing 100054C hina Key Laboratory of Beijing on Regional Air Pollution Control Beijing University of TechnologyBeijing 100124China

F-V2 O5-WO3/Ti02 catalysts were prepared by the impregnation *** the content of F ions increased from 0.00 to 0.35 wt.%,the NO conversion of F-V2 O5-WO3/TiO2 catalysts initially increased and then *** 0.2 F-V2 O5-WO3/TiO2 catalyst(0.2 wt.%F ion)exhibited the best denitration(De-NOx)performance,with more than 95%NO conversion in the temperature range 160-360℃,and 99.0%N2 selectivity between 110 and 280℃.The addition of an appropriate amount of F ions eroded the surface morphology of the catalyst and reduced its grain size,thus enhancing the NO conversion at low temperature as well as the sulfur and water resistance of the V2 O5-WO3/Ti02 *** selective catalytic reduction(SCR)reaction in a gas flow containing SO2 and H2 O,the number of NH3 adsorption sites,active component content,specific surface area and pore volume decreased to different *** sulfate species deposited on the catalyst surface,which blocked part of the active sites and reduced the NO conversion performance of the ***-line thermal regeneration could not completely recover the catalyst activity,although it prolonged the cumulative life of the *** addition,a mechanism for the effects of S02 and H2 O on catalyst NO conversion was proposed.

关键词： Fions Low temperature selective catalytic reduction Sulfur resistance On-line thermal regeneration

Fractional Fourier domain analysis of decimation and interpolation

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Science in China(Series F) 2007年第4期50卷 521-538页

作者： MENG XiangYi tao Ran WANG yue Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China

The sampling rate conversion is always used in order to decrease computational amount and storage load in a system. The fractional Fourier transform （FRFT） is a powerful tool for the analysis of nonstationary signals, especially, chirp-like signal. Thus, it has become an active area in the signal processing community, with many applications of radar, communication, electronic warfare, and information security. Therefore, it is necessary for us to generalize the theorem for Fourier domain analysis of decimation and interpolation. Firstly, this paper defines the digital frequency in the fractional Fourier domain （FRFD） through the sampling theorems with FRFT. Secondly, FRFD analysis of decimation and interpolation is proposed in this paper with digital frequency in FRFD followed by the studies of interpolation filter and decimation filter in FRFD. Using these results, FRFD analysis of the sampling rate conversion by a rational factor is illustrated. The noble identities of decimation and interpolation in FRFD are then deduced using previous results and the fractional convolution theorem. The proposed theorems in this study are the bases for the generalizations of the multirate signal processing in FRFD, which can advance the filter banks theorems in FRFD. Finally, the theorems introduced in this paper are validated by simulations.

关键词： decimation interpolation fractional Fourier transform sampling rate conversion the digital frequency in the fractional Fourier domain

Oversampling analysis in fractional Fourier domain

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Science in China(Series F) 2009年第8期52卷 1446-1455页

作者： ZHANG Feng tao Ran WANG yue Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China

Oversampling is widely used in practical applications of digital signal processing. As the fractional Fourier transform has been developed and applied in signal processing fields, it is necessary to consider the oversampling theorem in the fractional Fourier domain. In this paper, the oversampling theorem in the fractional Fourier domain is analyzed. The fractional Fourier spectral relation between the original oversampled sequence and its subsequences is derived first, and then the expression for exact reconstruction of the missing samples in terms of the subsequences is obtained. Moreover, by taking a chirp signal as an example, it is shown that, reconstruction of the missing samples in the oversampled signal is suitable in the fractional Fourier domain for the signal whose time-frequency distribution has the minimum support in the fractional Fourier domain.

关键词： fractional Fourier transform oversampling chirp signal

Throughput analysis for relay-aided interference channel in cognitive radio networks

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High Technology Letters 2011年第4期17卷 344-349页

作者： Lou Jia Luo tao yue Guangxin School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

This paper considers a two-user Gaussian interference channel aided by a single relay. Two source-destination pairs and the relay share a single common chaunel, and the relay assists both sources in communicating the messages to their respective destinations. This paper mainly focuses on the ＂amplify-and-forward＂（AF） relaying strategy for relay, and derives upper bound and lower bound on achievable sum rate accordingly. Next, the application of the above model in cognitive radio （CR） networks is considered. The schemes that can ensure the coexistence of the secondary user with the primary user are proposed, in the sense that there is no rate degradation for the primary user due to sharing of the channel. Further, the throughput of the secondary user in different communication scenarios is investigated.

关键词： interference channel relay achievable sum rate cognitive radio(CR) throughput