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2013 No. 6

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Article
Krull--Schmidt decomposition of the tensor products of certain simpleUq(gln)-modules at a root of unity
GU Hai-xia, WANG Jian-pan
2013, (6): 1-13.
Abstract:
Assume $\mathscr{F}$ to be a field of characteristic zero, and $q\in \mathscr{F}$ to be a root of unity. With $\mathscr F$ as the ground field and $q$ as the quantum parameter, let $\mathsf{s}_q(n)$ be the restricted quantum symmetric algebra of rank $n$, and $\Wedge_q(n)$ be the quantum exterior algebra of rank $n$. By [6], the homogenous components of both $\mathsf{s}_q(n)$ and $\Wedge_q(n)$ are simple $U_q(\mathfrak{gl}_n)$-modules. In this paper, we decompose the tensor product of any homogenous component of $\mathsf{s}_q(n)$ with any homogenous component of $\Wedge_q(n)$ into direct sum of indecomposable modules.
Transaction price analysis and high-frequency trading
LIU Chang, ZHENG Wei-an
2013, (6): 14-21.
Abstract:
In recent years, the rapid development of high-frequency trading in the global financial market have gained widely attention. Holding period for the assets is short but frequent and tiny yields in every trade cause the trading sensitive to the transaction cost, in which the transaction price is the core. In this paper, a new transaction price model is constructed with the position information. Applied to the MACD indicator strategy, it has a good performance and bring a better return.
Ruin probabilities of a bidimensional risk model with constant interest rate
ZHANG Yuan-yuan, WANG Wen-sheng
2013, (6): 22-31.
Abstract:
We studied two types of ruin in the bidimensional framework. For each type of ruin, we derived an integro-differential equation for the survival probability, and an explicit asymptotic expression for the finite-time ruin probability when claim sizes have heavy tailed distributions.
Valuing power options under a regime-switching model
SU Xiao-nan, WANG Wei, WANG Wen-sheng
2013, (6): 32-39.
Abstract:
The pricing of European style power call options was considered when the dynamics of the underlying risky asset are driven by the Markov-modulated Geometric Brownian Motion. In particular, the market interest rate, the appreciation rate and the volatility of the underlying risky asset switched over time according to the sates of the continuous time Markov chain process. Since the market is incomplete, the regime switching Esscher transform was employed to determine an equivalent martingale measure and derive the valuation of the options. Then, the numerical analysis of our result was given.
Pricing model of American collar option
CEN Yuan-jun
2013, (6): 40-45, 56.
Abstract:
Collar option is designed for invertors with a downside income, and for issuers with a limit loss. The mathematical pricing model of the American collar option can be formulated as a one-dimensional parabolic variational inequality, or equivalently, a free boundary problem. To solve this problem, the penalty method and PDE arguments are applied. The existence and uniqueness of the solution, the properties of the free boundaries, such as monotonicity, smoothness, and location, are presented.
Boundary value apaproach to solve a class of singularly perturbed problems with spike-type contrast structure
SONG Ci
2013, (6): 46-56.
Abstract:
For the internal layer problem, firstly, the original problem was partitioned into left and right problems from the transfer point at the internal layer region. Then, through the boundary value method, the left and right problems were converted into non-singularly perturbed problems. And by boundary layer correction technique, the original problem was directly converted into two non-singularly perturbed problems. Lastly, the efficiency of the boundary value method could be indicated by numerical tests.
Generalized Petersen graphs admit proper total colorings with four distinguishing constraints
YANG Chao, YAO Bing, WANG Hong-yu
2013, (6): 57-67.
Abstract:
The study of distinguishing coloring in graphs is derived from the frequency assignment problem in mobile communications. This paper introduced the concept of $4$-adjacent vertex distinguishing total coloring ($4$-avdtc) of a simple graph $G$. The minimum number of $k$ colors required for $G$ such that it satisfies a $4$-avdtc is denoted as $\chi^{\prime\prime}_{4as}(G)$. For generalized Petersen graphs $P(n,k)$, it was proved that $6\leq \chi^{\prime\prime}_{4as}(P(n,k))\leq 7$.
Maximal Serfling inequalities for the partial sums of random variables sequence and its application
LI Hui-bao, HU Xue-ping
2013, (6): 68-73.
Abstract:
Using the Serfling inequality, some moment inequalities for the partial sums of a class of random variables sequence are obtained, then we mainly discuss the large deviation and the strong convergence by applying these moment inequalities. Some results in relative literature are extended and sharpened.
A McCoy condition on noncommutative rings
WANG Wen-kang
2013, (6): 74-82.
Abstract:
Some right (resp., left) McCoy subrings of matrix ring and upper triangular matrix ring over a right (resp., left) McCoy ring are presented. At the same time, we also give that a right McCoy ring is not left McCoy and a left McCoy ring is not right McCoy. Consequently, reversible rings satisfy a McCoy condition.
Improved algorithm of wavelet thresholding for image denoising
GAO Wen-zhong, CHEN Zhi-yun, ZENG Qiu-mei
2013, (6): 83-92.
Abstract:
The algorithm of the image denoising based on wavelet thresholding shrinkage has been studied. On this basis of soft thresholding function, an improved thresholding function was proposed. The improved thresholding function uses BayesShrink thresholding and SureShrink thresholding to suppress the too many reservations of wavelet coefficients which are produced by SureShrink thresholding. Compared with traditional algorithm (the soft threshold function method (BayesShrink thresholding), the soft threshold function method (SureShrink thresholding), the hard threshold function method and the semi-soft threshold function method), in dealing with the image with few edge points, the processed image based on the improved algorithm has a higher Peak Signal to Noise Ratio(PSNR), a higher Signal to Noise Ratio(SNR), and a lower Mean Square Error(MSE). The processed image based on the improved algorithm is clearer.
Improved LDA model for microblog topic mining
XIE Hao, JIANG Hong
2013, (6): 93-101.
Abstract:
With the dramatic increase of Sina microblog users, microblog websites have been the platformsfor a wide spectrum of users to get information. Due to the fact that microblog is a special kind of text with the restricted length, traditional topic models could not be used to analyze the microblog content very well. RT-LDA, a microblog generation model based on LDA is proposed in this paper. Gibbs sampling is chosen to deduce the model, which can not only mine the topics of each microblog accurately but also induce the distribution of the concerned topics. RT-LDAs effective utility on topic mining of the microblogs is verified by the experiments on real data.
Weak signal DOA estimation method based on synthetic spectrum without prior knowledge of source number
HOU Shuai PAN Wei
2013, (6): 102-111.
Abstract:
For the problem of the source number and DOA estimation of the weak signals in the interference of the strong signals, a novel method based on synthetic spectrum is proposed. In this method, the outputs of the eigen-beam channels are superimposed by different weights to form a spatial spectrum function. Then the function is used to weight the spatial spectrum function derived from the noise subspace approximation method. Finally, the synthetic spectrum function is constructed to estimate the DOAs of the weak signals without the prior knowledge of source number. Compared to the prevois method based on eigen beamforming, the proposed method has better performance when the DOAs of weak signals are close to each other. The effectiveness and advantage of this method is verified by the simulation results.
Mg(Zn, Mn)-doped Cobalt ferrites: a first-principles study
XIAO Tian-liang, DING Hang-Chen, GONG Shi-Jing, DUAN Chun-gang
2013, (6): 112-119.
Abstract:
Using generalized gradient approximation plus U method, we present electronic and magnetic properties through a systemic theoretical calculation of YxCo1-xFe2O4(Y=Mg, Zn, Mn,x=0.00, 0.25, 0.50, 0.75, 1.00). Our main results show that: ① the octahedral Co2+B ions may show high/low spin states under different doping concentration x; ② magnetic moments of high spin state for Co2+B can be changed by different doping degrees, it ranges from 2.54B to 2.85 B; ③ the spinel structure will change from metal to half-metal at the inversion degree region from 0.75 to 1.00.
Influence of electrical conductivity of multi-walled carbon nanotubes by halogen-doping
SHI Guo-Xian XU Xue-Cheng
2013, (6): 120-126.
Abstract:
Multi-walled carbon nanotubes (MWNTs) were doped by chlorine, bromine and iodine. Compared with the pristine MWNTs, the electrical conductivities of Cl2-MWNT and Br2-MWNTs were improved over 5 times and 3 times, respectively, while that of I2-MWNTs almost unchanged. The interaction between the halogen and MWNTs was analyzed by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Meanwhile, we also studied the carrier concentration and carrier mobility which may affect the conductivities of the composite. The results show that: When the halogen electronegativity become stronger, the mean free path of the carrier of doped MWNTs will be higher, as well as the carrier mobility. And the stonger the interaction between the halogen and MWNTs become, the more carriers will take part in conducting, which means the carrier concentration will be higher.
Influence of pH value on the properties of the composite wires by chemical deposition
LUAN Hong-yan, LI Xin, WANG Rui-li, PAN Hai-lin, CHEN De-lu, ZHAO Zhen-jie
2013, (6): 127-132.
Abstract:
Composite wires of 100 m diameter CuBe coated with a layer of NiCoP were prepared by chemical plating, and dc current of 150 mA got through CuBe wires during the process. The influence of pH value on the composite wires was studied in terms of morphology, deposition speed, composition, magnetic property and the GMI effect. The results showed that the pH value influenced GMI effect and critical frequency by changing the roughness of materials, deposition speed, the coating composition and magnetic structure. The maximum GMI effect of 868% is obtained at the pH value of 8.4.
Properties of novel poly (aryl ether quinoxaline)s (PEQs)
ZHAO Qiu-tang, Ding Ya-ming, HUA hui
2013, (6): 134-140.
Abstract:
Novel poly(aryl ether quinoxaline)s (PEQs) were prepared via a new two-step procedure. Firstly, poly (ether benzil) (PEB) was synthesized by the polycondensation of 4,4-difluorobenzil and 4,4-isopropylidenediphenol. Then, PEQs were synthesized through chemical modification of PEB by 1,2-diaminobenzene and a small amount of 4,4-oxydibenzene-1,2-diamine(OBDA). The polymers were characterized by IR, NMR, TMA and other measurements. Experiments show that these PEQs can be dissolved in common organic solvents, such as DMF and THF; these PEQs were dissolved in THF to get films which had good transmittance in the visible region (the transmittance was up to 85% at 450 nm). In addition, they also had higher glass transition temperatures (Tg210 ℃), good thermal and mechanical properties, as well as excellent resistance to strong acid and alkali. They are expected to be useful functional materials.
Poly (L-γ-glutamylglutamine) nanoparticles enhance drug accumulation in resistant cells
LIU Kai, CHEN Jing, WANG Jing, YU Lei, ZHU Jian-zhong, WANG Yi-ting
2013, (6): 141-149.
Abstract:
This work investigated the antitumor efficacy of poly (L--glutamylglutamine) (PGG) prodrug in multidrug resistant (MDR) cancer cells and the possible mechanisms. The A549 cell line was induced to become multidrug resistant. A549 was applied to evaluate the effect of PGG-Dox on intracellular accumulation and retention of Dox.Endocytosis inhibition studies and transmission electron microscope assay were used to investigate the mechanisms of cellular PGG-Dox uptake. Confocal laser scanning microscopy was performed to confirm the drug accumulation. Treatment of MDR cells with PGG-Dox resulted in significantly enhanced drug accumulation and retention after the end of treatment compared with free Dox. Endocytosis inhibition studies showed pinocytosis is the mainly pathway in the elevated membrane permeability of the PGG-Dox. These demonstrated that Dox conjugate with PGG NPs effectively bypass the multidrug resistance. Our PGG DDS may be considered as an attractive and promising delivery system to overcome multidrug resistance.
Characters on the seed dormancy and germination of an endangered species, Ostrya rehderiana, in Tianmu Mountain, China
LE Xiao-wei, CUI Min-yan, YANG Shu-zhen, LUO Yuan, ZHAO Ming-shui, LI Yuan-yuan
2013, (6): 150-158.
Abstract:
Ostrya rehderiana is a critically endangered plant species with only five natural individuals remaining in Tianmu Mountain, Zhejiang Province, China. To explore the seed dormancy and germination of O. rehderiana, the seeds were collected from the natural individuals in November 2008 and 2009 and manipulated in illumination incubator in different treatments. Results showed that these seeds have a water absorption rate of 20% after immerging in water for 4 h (p0.05), indicating it was not physical dormancy (PY). The seeds have higher cumulative germination rates after short low temperature storage (4 weeks v.s. 16 weeks; p0.05), suggesting low temperature might induce seeds dormancy of O. rehderiana. To break dormancy, relative longer times (median length of germination time=54 d) of temperature above 15 ℃ were needed, indicating the seeds may belong to physiological dormancy (PD). The most favorable germination condition was 15/25 ℃ employing 400 or 600 mgL-1 GA. We conclude that seeds treated with GA should be sown in a fitting condition immediately to germinate well in the ex situ conservation of O. rehderiana. In addition, it is a feasible method that seeds germinate in the nature with added GA artificially.
Analysis of sugar metabolism and its related enzymes activities during vase-holding days of cut rose petal
LI Long, WANG Hai-hong, CHEN Zhao-liang, QIAO Yong-jin, WANG Li
2013, (6): 159-164.
Abstract:
Analyze changes of sugar metabolism and its related enzymes activities during vase-holding days of cut roses named cv. Black Magic flower and cv. Movie Star flower were studied. The results showed that glucose and fructose contents increased rapidly with the cell enlargement in the petals and during flower growth, but the content of sucrose dropped gradually. The cut rose named cv. Movie Star flower had a larger hexoses (glucose+fructose) content , fresh weight and a bigger flower diameter fresh weight than cv. Black Magic flower . The activity of acid invertase (AI) was always at a higher level than those of the neutral invertase (NI), sucrose synthase (SS) and sucrose phosphate synthase (SPS). The activity of acid invertase (AI) was positively correlated with sucrose degradation index (SDI). In conclusion, the acid invertase (AI) was a key enzyme in the sucrose degradation and hexoses accumulation, while hexose accumulation in the petal might be important for flower growth and development in cut rose.
HPLC-ESI-MS determination of neurotransmitters L-serine/D-serine in rat brain tissues
WANG Wei-li, DUAN Ya-le, LIU Sha, ZHANG Yao, ZHAO Zheng
2013, (6): 165-170.
Abstract:
A highly sensitive and selective high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) assay was developed for the determination of neurotransmitters L-serine/D-serine in rat brain tissues. The rat brain was removed, homogenized and centrifuged.L-serine/D-serine in the supernatant was derivatized with the Marfeys reagent. The derivatives were separated by HPLC under gradient elution of mobile phase consisting of ammonium formate and acetonitrile and detected by ESI-MS in the negative ion mode. Reverse phase chromatographic resolution of the enantiomers was obtained within 22 min. Good linear correlations of the concentration to the peak area were obtained in the ranges of 2.5~500 ng/mg for L-serine and 1.2~250 ng/mg for D-serine. The extraction recoveries for both analysts were in the range of 81% to 89%. The method was then applied to determine the levels of the neurotransmitters in cerebral cortex and hippocampus of the adult and aged rats. The results showed that L-serine levels kept unchanged,while D-serine levels decreased significantly, in cortex and hippocampus of the aged rats compared with those of the adult rats, suggesting an involvement of D-serine in the normal aging process.
Analysis of gal-3 gene diversity of Bufo gargarizans
PAN Li-nian, WAN Wen-bin, ZHANG Shu-fang, ZHU-GE Hui,  ZHOU Pin-pin, YANG Xian-yu
2013, (6): 171-180.
Abstract:
Three independent groups of first-strand cDNAs were synthesized from the total RNA extracted from the skin of a single individual of Bufo gargarizans using different kits including SMARTer TM RACE cDNA Amplification Kit and modified Quantscript RT kit, which were then used as templates for the subsequent polymerase chain reaction (PCR). The PCR products were cloned into the pGM-T vector and sequenced. As a result, 16 different uni-cDNAs were singled out of the total 31 cDNA clones. Same sequences, single nucleotide polymorphism sites (SNPs) and base deletions were detected in two or three independent experiments/groups, indicating gal-3 diversity, which led to diversity of proteins encoded. But alignment of the amino acid residues deduced form these gal-3 cDNAs revealed high conservation of glycosyl-binding sites, phosphorelation sites and the motifs highly associated with biological functions, which suggested the existence of galectin-3 diversity in the skin of B. gargarizans.
Development and application of the Cross-platform Intelligent e-Education Service Platform
WU Yong-he, HE Chao, FENG Xiang, WANG Jian, SHEN Jian, REN You-qun
2013, (6): 181-192.
Abstract:
The Cross-platform Intelligent e-Education Service Platform (CIeESP) is a major task of scientific research assigned by the Science and Technology Committee of Shanghai Municipality, with its main goal being to build the cross-platform intelligent e-education service platform and study its business model. This paper introduced the development and application of the platform from three aspects: design idea, system design and implement. First, the CIeESP plat form based on cloud service and four subsystems, including Education Resource Management Subsystem, Learning Subsystem Based on Mobile Terminal, Education Resource Supermarket Subsystem and Online Interactive Learning Subsystem, are explained from technology resolution, system deployment and application. Second, the development of education resource based on two-dimension code is illustrated, and its demonstration and model are provided from two kind of services based on two-dimension code and of online interactive learning and business model, respectively. Then the usability test for the System is described. Finally, summary and outlook are given.
QR-code based design of supplementary book service platform
FENG Xiang, WU Yong-he, WANG Jian, REN You-qun
2013, (6): 193-201.
Abstract:
This study applied two-dimensional code in the design of a supplementary book distribution system: used it as the entrance to the digital world, constructed a services platform, developed a mobile application for ubiquitous learning, and built a supplementary publishing ecosystem. The study connects supplementary books and digital supplementary resources seamlessly, providing better learning experience. The research result has been applied by the Press of East China Normal University in distribution of paper supplementary books and yield good results.