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Chain store game based channel allocation in cognitive radio system

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 1-8页

作者： LI Jin-long zhu Ping WANG Xu-fa School of Computer Science and Technology University of Science and Technology of China Hefei 230027 China

In adaptive channel allocation for secondary user （SU） of cognitive radio （CR） system, it is necessary to consider allocation process from the temporal perspective. In this article, a chain store game is modeled to achieve SU＇s equilibrium state. Due to the computational complexity of solving equilibrium states, the authors explore the correlated equilibrium （CE） by importing signal mechanisms based on time and sequence number. Also, correlated equilibrium based game algorithms are presented. Simulations show that these algorithms are superior to other allocation algorithms both in channel utilization and communication time.

关键词： CR dynamic specturm allocation chain store game Nash equilibrium (NE) correlated equilibrium (CE)

Spin-Dependent Electron Properties of a Triple-Terminal Quantum Dot Structure

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Communications in Theoretical Physics 2009年第12期52卷 1117-1124页

作者： HAN Yu GONG Wei-Jiang WEI Guo-zhu Department of Physics Liaoning University Shenyang 110036 China College of Sciences Northeastern University Shenyang 110004 China International Center for Material Physics Acadmia Sinica Shenyang 110015 China

Electron transport properties of a triple-terminal Aharonov-Bohm interferometer are theoretically *** applying a Rashba spin-orbit coupling to a quantum dot locally, we find that remarkable spin polarization comesabout in the electron transport process with tuning the structure parameters, i.e., the magnetic flux or quantum dotlevels. When the quantum dot levels are aligned with the Fermi level, there only appear spin polarization in thisstructure by the presence of an appropriate magnetic flux. However, in absence of magnetic flux spin polarization andspin separation can be simultaneously realized with the adjustment of quantum dot levels, namely, an incident electronfrom one terminal can select a specific terminal to depart from the quantum dots according to its spin state.

关键词： quantum dot electron transport Rashba interaction

Mesozoic Deformation and Its Geological Significance in the Southern Margin of the South China Sea

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Journal of Ocean University of China 2018年第4期17卷 835-845页

作者： zhu Rongwei LIU Hailing YAO Yongjian WANG Yin CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesCruangzhou 510301China Guangzhou Marine Geological Survey Guangzhou 510760China University of Chinese Academy of Sciences Beijing 100049China

The pre-Eocene history of the region around the present South China Sea is not well known. New multi-channel seismic profiles provide valuable insights into the probable Mesozoic history of this region. Detailed structural and stratigraphic interpretations of the multi-channel seismic profiles, calibrated with relevant drilling and dredging data, show major Mesozoic structural features. A structural restoration was done to remove the Cenozoic tectonic influence and calculate the Mesozoic tectonic compression ratios. The results indicate that two groups of compressive stress with diametrically opposite orientations, S(S)E– N(N)W and N(N)W–S(S)E, were active during the Mesozoic. The compression ratio values gradually decrease from north to south and from west to east in each stress orientation. The phenomena may be related to the opening of the proto-South China Sea(then located in south of the Nansha block) and the rate at which the Nansha block drifted northward in the late Jurassic to late Cretaceous. The Nansha block drifted northward until it collided and sutured with the southern China margin. The opening of the present South China Sea may be related to this suture zone, which was a tectonic zone of weakness.

关键词： southern continental margin of the South China Sea Mesozoic deformation structure structural restoration proto-South China Sea

Synthesis of dimethyl 3-perfluoroalkyl-4-(3-oxo-2-triphenyl-phosphoranylidenbutanylidene)-pent-2-enedioate and its cyclization

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Chinese Journal of Chemistry 1995年第5期13卷 468-474页

作者： Ding, WY Cao, WG Yao, Y zhu, ZM SHANGHAI UNIV SCI & TECHNOL DEPT CHEMSHANGHAI 201800PEOPLES R CHINA

The title compounds 5a-5c were prepared via the reaction of methyl 2-perfluoroalkynoates (4) with methyl 5-oxo-4-(triphenylphosphoranylidene)hex-2-enoate (3), which was obtained from the reaction of methyl propynate (2) with acetylmethylenetriphenylphosphorane (1) at -5-0 degrees C. Intramolecular elimination of Ph(3)PO took place when compound 5 was heated in aqueous methanol at 115-120 degrees C in sealed tube, yielding dimethyl 2-trifluoromethyl-4-methylisophthalate (6a) from 5a and methyl 5-acetyl-4-hydroxy-2-heptafluoropropanylbenzoate (6b) from 5b, respectively. The structures of compounds 5, 6a and 6b were confirmed by IR, MS, H-1 NMR, F-19 NMR and C-13 NMR spectroscopy and elemental analyses. Rection mechanisms for the formation of compounds 5, 6a and 6b were proposed.

关键词： phosphorane polysubstituted arene intramolecular cyclization

Variable partial-update NLMS algorithms with data-selective updating

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Science China(Information Sciences) 2014年第4期57卷 42-52页

作者： zhu FengChao GAO FeiFei YAO MinLi ZOU HongXing Tsinghua National Laboratory for Information Science and Technology Department of AutomationTsinghua University High-Tech Institute of Xi'an

We note that some existing algorithms are based on the normalized least-mean square(NLMS)algorithm and aim to reduce the computational complexity of NLMS all inherited from the solution of the same optimization problem,but with different constraints.A new constraint is analyzed to substitute an extra searching technique in the set-membership partial-update NLMS algorithm(SM-PU-NLMS)which aims to get a variable number of updating coefficients for a further reduction of computational *** get a closed form expression of the new constraint without extra searching technique to generate a novel set-membership variable-partial-update NLMS(SM-VPU-NLMS)*** that the SM-VPU-NLMS algorithm obtains a faster convergence and a smaller mean-squared error(MSE)than the existing *** is pointed out that the closed form expression can also be applied to the conventional variable-step-size partial-update NLMS(VSS-PU-NLMS)*** novel variable-step-size variable-partial-update NLMS(VSS-VPU-NLMS)algorithm is also verified to get a further computational complexity *** results verify that our analysis is reasonable and effective.

关键词： adaptive filter NLMS algorithm date-selective partial update set-membership filtering computational complexity

Verification and recalibration of HY-2A microwave radiometer brightness temperature

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Journal of Oceanology and Limnology 2019年第3期37卷 968-981页

作者： ZHAO Yili LI Huimin CHEN Chuntao zhu Jianhua National Ocean Technology Centre Tianjin 300112China Laboratoire d’Oceanographie Physique et Spatiale IfremerPlouzané 29280France

HY-2A is the first one of the Chinese HY-2 ocean satellite series carrying a microwave radiometer(RM)to measure sea surface temperature,sea surface wind speed,atmospheric water vapor,cloud liquid water content,and rain *** verified the RM level 1B brightness temperature(T B)to retrieve environmental *** the verification,TB that simulated using the ocean-atmosphere radiative transfer model(RTM)was used as a *** total bias and total standard deviation(SD)of the RM level 1B TB,with reference to the RTM simulation,ranged-20.6-4.38 K and 0.7-2.93 K,*** found that both the total bias and the total SD depend on the frequency and polarization,although the values for ascending and descending passes are *** addition,substantial seasonal variation of the bias was found at all *** verification results indicate the RM has some problems regarding calibration,e.g.,correction of antenna spillover and antenna physical emission,especially for the 18.7-GHz *** on error analyses,a statistical recalibration algorithm was designed and recalibration was performed for the RM level 1B *** of the recalibrated TB indicated that the quality of the recalibrated RM level 1B TB was improved *** bias of the recalibrated T B at all channels was reduced to<0.4 K,seasonal variation was almost eradicated,and SD was diminished(i.e.,the SD of the 18.7-GHz channel was reduced by more than 0.5K).

关键词： HY-2A microwave radiometer brightness temperature(TB) verification calibration

Modification of Nano Tourmaline Surface Treatment Agent and Its Performance on Negative Ion Release

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Computers, Materials & Continua 2018年第10期57卷 145-150页

作者： Guorui Huang Zhongkai Cui Pengfei zhu Xiaoyun Liu East China University of Science and Technology No.130 Meilong RoadShanghai200237China Department of Chemistry Universitéde MontréalC.P.6128Succ.Centre VilleMontréalQuébecCanadaH3C 3J7

In this paper,a kind of wall fabric’s surface treatment agent modified with nonionic surfactant was *** surface treatment agent was prepared by using nano tourmaline powder dispersion in water with surfactant as dispersants by sand *** the influence of different dispersants,the negative ions releasing amount of functional wall fabrics,the milling process and the storage stability of nano tourmaline powder dispersion were *** results showed that nano tourmaline powder dispersion achieved the smallest average diameter of 44 nm and had best storage stability that the average diameter maintained below 200 nm in 17 days when the addition amount of dispersant was 20 percent of the tourmaline powders’*** is more,the quantity of negative ion releasing achieved 6500 ion/cm3 when addition amount of dispersant was 30 *** technique could be used to strengthen productivity of nano tourmaline powder dispersion.

关键词： Tourmaline dispersant negative ion storage stability wall fabrics

Molecular Biological and Biochemical Studies Reveal New Pathways Important for Cotton Fiber Development

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Journal of Integrative Plant Biology 2007年第1期49卷 69-74页

作者： Yu Xu Hong-Bin Li Yu-Xian zhu National Laboratory of Protein Engineering and Plant Genetic Engineering Peking University Beijing 100871 China

As one of the longest single-celled seed trichomes, fibers provide an excellent model for studying fundamental biological processes such as cell differentiation, cell expansion, and cell wall biosynthesis. In this review, we summarize recent progress in cotton functional genomic studies that characterize the dynamic changes in the transcriptomes of fiber cells. Extensive expression profilings of cotton fiber transcriptomes have provided comprehensive information, as quite a number of transcription factors and enzyme-coding genes have been shown to express preferentially during the fiber elongation period. Biosynthesis of the plant hormone ethylene is found significantly upregulated during the fiber growth period as revealed by both microarray analysis and by biochemical and physiological studies. It is suggested that genetic engineering of the ethylene pathway may improve the quality and the productivity of cotton lint. Many metabolic pathways, such as biosynthesis of cellulose and matrix polysaccharides are preferentially expressed in actively growing fiber cells. Five gene families, including proline-rich proteins （PRP）, arabinogalactan proteins （AGP）, expansins, tubulins and lipid transfer proteins （LTP） are activated during early fiber development, indicating that they may also be needed for cell elongation. In conclusion, we identify a few areas of future research for cotton functional genomic studies.

关键词： cotton fiber functional genomics plant hormone transcriptome transcription factors

Purification and Immunity Analysis of Recombinant 6His-HPT Protein Expressed in ***

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Biomedical and Environmental Sciences 2003年第2期16卷 149-156页

作者： LI-CHEN YANG ZHEN zhu XIAO-GUANG YANG Plant Genetic Manipulation Laboratory Institute ofGeneticsChinese Academy of SciencesBeijing 100101China Key laboratory of Trace Element Nutrition ofthe Ministry of Health ChinaInstitute of Nutrition and Food SafetyChinese Centerfor Diseases Control and PreventionBeijing 100050Chin

To obtain HPT protein (Hygromycin B Phosphotransferase), a kind of plant selective maker gene product expressed from *** and to prepare the polyclonal antibody (pAbs) against it. Methods HPT cDNA fragment was obtained by PCR and was inserted into the prokaryotic expressing vector pBV222. Then the constructed recombinant plasmid pBV222-HPT was transfered into *** DH5?for HPT expression. The recombinant expressing system was confirmed by restriction endonuclease digestion, DNA sequencing and protein expression. *** cells were lysed by sonication and detergent dissolution. After cell membrane was extracted, the inclusion bodies were denatured by 8 mol/L Urea and purified with metal chelate affinity chromatography on Ni-NTA agarose under denaturing condition. The purified 6His-HPT was characterized by SDS-PAGE, and used to immunize rabbit. The titer and specificity of antisera were detected by ELISA and Western blot respecitively. Results Analysis of DNA sequence and restricted enzymes showed that the sequence of PBV222-HPT plasmid was correct. The amount of recombinant HPT expressed in *** accounted for 30% of total cellular proteins. From 1 liter of fermentative bacteria about 22 milligrams of pure recombinant HPT was isolated with purity above 95%. The recombinant HPT protein could produce high titer antiserum in rabbits and show good immunity activity. Western blot showed specific binding reaction between the antiserum to the purified 6His-HPT protein and their expressed products (plants protein and bacterial protein). Conclusion HPT protein can be expressed and purified from *** by a relatively simple method, which has high immunity activity.

关键词： HPT Expression and purification E. coli Immunity activity