最新刊期
卷 52 ， 期 4 ， 2013
- 摘要：Face image can be decomposed into the lowfrequency component and highfrequency component by image decomposition method. Lowfrequency component characterizes face images illumination while highfrequency component describes its detail structure. Thus, highfrequency component is frequently used as illumination insensitive features for image recognition, but its performance will be affected by illumination variations because highfrequency component in the shadow area of the illuminated face image will be distorted after the decomposition. The method of restoring illuminated face image is proposed which consists of the following three steps: ① based on the PCA method, using the highfrequency information of local lighting area of an illuminated face image to restore highfrequency components of its asymmetrically illuminated area; ② using illumination of local lighting area to restore the holistic symmetrical frontal illumination components; and ③ fusing the restored lowfrequency illumination and highfrequency illumination, obtaining the symmetrical frontalilluminated face image without illumination effect and thus realizing face images lighting recovery. The proposed method is applied in the Yale B and acquires the restored illuminated face image with good performance in visual effect and recognition.关键词：high-frequency component;low-frequency component;fusion;relighting
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发布时间：2023-12-11 - 摘要：Visual location is one of the most important issues in robot visual navigation. The locating efficiency has a large impact on the performance of the visual navigation. A fast visual location method is proposed: BRISK is employed as the local invariant features, the scene model based on aggregate is described and the similarity of the scenes is measured by Sorensen coefficient to avoid complex computation for efficiency. The method has been verified by simulation and experiment with a humanoid robot in indoor environment. The effectiveness is 99% and the average measuring time is 003 s (33 fps). The result demonstrates that the method has good performance in terms of effectiveness, robustness and real time.关键词：visual location;visual navigation;BRISK feature;similar scene;sorensen coefficient
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发布时间：2023-12-11 - 摘要：Stock index futures plays an important role in the process of price discovery and risk prevention of capital market. The prediction of its return volatility is significantly important to achieve the risk aversion function of stock index futures. A semiparametric forecasting model based on the linear nonnegative autoregressive model is proposed to forecast the realized volatility of stock index futures, and the asymptotic properties of estimation method for this model are analyzed. In addition, taking 5 min highfrequency trading data of CSI300 index futures as example, the outofsample daily volatility predictions calculated by using rolling predicting method, and a bootstrap MCS test is used to evaluate the predicting accuracy for the proposed model and other 7 models. The empirical results show that, under various robust loss functions, the proposed model is the best model for volatility predictions of stock index futures among the 8 models.关键词：semiparametric forecasting model;stock index futures;realized volatility;MCS test
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发布时间：2023-12-11 - 摘要：A subgroup H of G is said to be weakly Sembedded in G, if for some normal subgroup T of G, HT is S-permutable in G and H ∩ T ≤ Hsewhere Hseis an S-permutably embedded subgroup of G contained in H. The influence of some weakly S-embedded subgroups on the supersolublity of a finite group G is investigated. And some results about formations are obtained.关键词：S-permutable subgroup;weakly S-embedded subgroup;supersoluble group;formation
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发布时间：2023-12-11 - 摘要：The oscillation for certain thirdorder nonlinear variable delay dynamic equations with nonlinear neutral term on time scales is discussed. By using the generalized Riccati transformation and a lot of inequality techniques, some new oscillation criteria for the equations are established. Some known results are extended and improved. Examples are given to illustrate the main results.关键词：oscillation;delay dynamic equations;Riccati transformation;time scales
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发布时间：2023-12-11 - 摘要：Conformal welding plays an important role in the development of Teichmu¨ller theory and quasiconformal maps. The discrete approximations of conformal welding and associated quasicircle induced by a quasisymmetry mapping are constructed using circle packings with bounded degree, and their convergence is proved. This provides a more general approach for approximating conformal welding mappings.关键词：circle packing;conformal welding;quasicircle;quasisymmetry
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发布时间：2023-12-11 - 摘要：Based on the packet reception model for real wireless links, a cooperative beaconless reliable routing protocol (CBRR) is proposed. CBRR provides a novel forwarding policy combining with contention forwarding and cooperation forwarding, which can achieve the reliable guarantee between a single hop by the priority of waiting delay, cooperative probability guaranty and redundancy transmitting. Furthermore, CBRR can obtain packet reception rate through RTSCTS handshake without using probing messages. Simulation results verify the validation of CBRR in term of its high reliability with better energy efficiency and shorter delivery delay.关键词：wireless sensor networks;reliable routing;beaconless forwarding;cooperative communication
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发布时间：2023-12-11 - 摘要：The Noether symmetry and the conserved quantity for a fractional actionlike variational problem in phase space are studied based on the method of fractional dynamics modeling presented by El-Nabulsi, namely fractional actionlike variational approach. First, the fractional actionlike variational problem in phase space is established, and the fractional actionlike Hamilton canonical equations are obtained. Secondly, the definitions and criteria of the fractional actionlike Noether (quasi)symmetrical transformations are presented in terms of the invariance of the fractional actionlike integral of Hamilton under the infinitesimal transformation of group. Finally, the Noether theorems for the fractional actionlike Hamiltonian system are given, the relationship between the Noether symmetry and the conserved quantity of the system is established.An example is given to illustrate the application of the results.关键词：fractional action-like variational approach;Noether theorem;phase space;fractional action-like symmetrical transformation;conserved quantity
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发布时间：2023-12-11 - 摘要：in the framework of public key infrastructure (PKI) network security theory. By the interactive data process, the protocol can fully achieve important performances of the security and authenticity for user key and fingerprint information, and can safely resist for the two common attacks of Stolenverifier and Replay, therefore the protocol can apply for identity authentication system in network e-commerce environment.关键词：fingerprint identification;digital watermarking;identity authentication;protocol
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发布时间：2023-12-11 - 摘要：A semi-empirical approach to the critical analysis of thermodynamic data is proposed and applied in this work. A critical analysis of heat capacities of the sixteen isostructural AIIIBVcompounds was then made based on the correlative optimization method. A set of mutually agreed equations CoP=a+b·10-3·T-c·105·T-2was proposed to describe the heat capacities of these phases. Two continuums of relations CoP(T) vs. logarithm of the sum of atomic numbers of elements A and B were obtained for the AIIIBVphases, of both sphalerite and wurtzite types, in the temperature range from 260 to 1 500 K. Based on the proposed equations, heat capacity values were predicted for the previously unstudied (or poorly studied) phases TlN and AlP within the temperature ranges of 260~1018 K and 260~1 500 K, respectively. The proposed correlative method of thermodynamic functions can be applied to other inorganic and organic isostructural compounds,other different groups of isostructural organic and inorganic compounds.
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发布时间：2023-12-11 - 摘要：the design of servo signal timing recovery model plays a important role in the performance of read/write channel of micro hard disk. A servo interpolated timing recovery model is proposed based on the τ factor, which is used to solve the disadvantages of timing recovery model based on the phaselocked loops. It derives that the arithmetic for τ factor interpolator obtains the test result, compared with the arithmetic for linear interpolation method which shows that the reduction of content of harmonic is doubled, based on the τ factor servo interpolated timing recovery model.关键词：servo signal;timing recovery;τfactor;Interpolator
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发布时间：2023-12-11 - 摘要：A histogram equalization method is proposed. Firstly, The image is divided into low and high frequency use mean filtering. Then, various classical histogram equalization methods can be selected to deal with Lowfrequency information and highfrequency information respectively, a new method of selecting appropriate adjustment factor is presented to suppress noise from different extent. Finally, the low and high frequency information is combined to reconstruct the whole image. Experiments show that the dynamic range of the image gray levels is stretched effectively with improving contrast, image detail is well retained, noise amplification and overenhancement are also avoided.关键词：mean filtering;over-enhancement;histogram equalization
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发布时间：2023-12-11 - 摘要：The development and implementation of the remote real-time monitoring system for baseisolated buildings in the Wenchuan post-disaster reconstruction is presented. The education building of Wenchuan No.1 Primary School, the education building of Wenchuan No.2 Primary School, and the Yingxiu Settlement Buildings are under realtime structural monitoring by the system. The Wenchuan 5-12 Earthquake has past for almost 5 years and the system has been normally working for 1 year. It has been successfully recorded and preliminarily analyzed for the monitoring structures under several small earthquakes. The system can be regarded as a working platform for further research on isolated structure theory and isolation engineering measurement analysis. It can also be preparatory technical work for baseisolated structure monitoring under possible violent earthquake.关键词：Wenchuan post-disaster reconstruction;isolated building;remote real-time monitoring
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发布时间：2023-12-11 - 摘要：Relational database is a very satisfiable transaction processing in enterprise management, however, with the advancing of Web20 era, there are more and more people increasingly focus on the exceptional performance of highconcurrency accessing of unstructured data. As to the question of the combination and extension of relational database and NoSQL schema, the paradox of data consistency and high-performance data access can be solved by the redeconstruct of data and access instruction in the data accessing process of traditional database, which implement the idea of dividing the data access into schema and schemaless process. At last, the test in mass-concurrent insertion, query, and other database operations of the same data have been made in the same MySQL database. The results under schema and schema-less environment prove this solution is more efficient than relational database.关键词：unstructured data;relational database;RDBMS;NoSQL;schema;ACID;CAP
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发布时间：2023-12-11 - 摘要：Theoretical and experimental research on fire caused by smoldering reaction is insufficient in contrast with that on flame combustion. Especially the fullscale experimental study of smoldering combustion of porious combustible materical in open room is scarce. Based on experiments of cellular combustible material, polyurethane, on a selfmade testbed in an ISO9705 fire room, the change trends on both ignition temperature and heating rate are analyzed under different initial heating flux. Further, the chemical reaction and supercritical temperature of smoldering ignition in open space are obtained and analyzed during the research.关键词：smoldering combustion;cellular combustible material;open space;ignite
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发布时间：2023-12-11 - 摘要：It is important to study the interaction of small molecules with silk peptide. In this paper, the interaction of reactive dark blue M2GE(RDBMG) with silk peptide was studied by means of multiple spectroscopy. The binding distance and binding ratio were calculated as 304 nm and 1∶〖KG-*2〗1, respectively. Additionally, the effects of foreign substances in dyeing system such as surfactants, ionic liquids, metal ions, oxidants, textile pulp, and seven kinds of amino acids (histidine, L-aspartic acid, L-lysine, L-arginine, L-methylthio amino acid, L-leucine and L-proline) on SP RDBMG were also investigated. The results showed that the binding constants increased when Ionic liquids including chloride hydroxyethyl trimethyl amine, bromide 1-ethyl-2,3–dimethyl imidazolium, 1-ethyl-2,3-methyl imidazolium bis-［trifluoromethyl-sulfonyl］ imide, textile pulp (original starch, phosphate starch, oxidized starch), metal ions (Ca2 +, Zn2 +, Ba2 +), surfactants(CTAB, Triton X-100, sodium dodecyl sulfate) and seven types of amino acids were added into SPRDBMG. However, the binding constants decreased when polypropylene aldehyde amine, aldehyde ester starch, Cu2 + and oxidants (φ=30%H2O2K2S2O8K2Cr2O7) were in the presence of SP-RDBMG.关键词：silk peptide;reactive dark blue M-2GE;fluorescence spectroscopy;textile auxiliary
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发布时间：2023-12-11 - 摘要：To determine and analyze free amino acids in Borojo.The sample was derivatized with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) and then was analyzed with highperformance liquid chromatography (HPLC). HPLC was performed on a Phenomenex C18(250mm × 4.6 mm, 5 μm) column with gradient elution of deionized water (A), acetonitrile (B) and 10 mmol/L ammonium acetate buffer solution(adjusted to pH 5-10 with glacial acetic acid) (C) at the flow rate of 0.8~1.0 mL/min, detected with Ultra Voilet (UV) at 248 nm. Linear relationship equations were obtained with 18 kinds of amino acids in the range of 0.02~0.5 mmol/L, and their correlation coefficients were in the range of 0.998 3~0.999 2. Fourteen amino acids were detected and average recoveries of those added were in the range of 96.9 %~106.9 % and RSD values were in the range of 0.67 %~3.07 %. The method could be used for determination of content of free amino acids in Borojo.关键词：Borojo;AQC;free amino acids;pre-column derivatization
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发布时间：2023-12-11 - 摘要：Novel bluish-violet Zn4B6O13and yellow-green Zn4B6O13: Mn2+long lasting persistence materials were synthesized by the solid state method. X-ray diffraction (XRD), photoluminescence and excitation spectroscopy, persistent luminescence spectroscopy and decay analysis and thermoluminescence were employed to characterize the structure and optical properties of these materials. Zn4B6O13showed two fluorescent emission peaks located at about 350 nm and 430 nm, which were similar to the persistent luminescence. Zn4B6O13samples maintained the persistent luminescence of about 30 min. The fluorescence and persistent emission peak of Zn4B6O13: Mn2+located at about 540 nm. Moreover, thermoluminescence measurement revealed that Zn4B6O13host had at least three defect centres, corresponding thermoluminescence peaks at about 345, 405 and 530 K, respectively. Two defect centres (at 345 and 405 K) were responsible for producing blueviolet persistent luminescence of Zn4B6O13materials. The thermoluminescence peak of Zn4B6O13: Mn2+sample located at 350 K, resulting in yellowgreen persistent luminescence of Zn4B6O13: Mn2+materials.关键词：long afterglow;borate;defect Luminescence;fluorescence spectrum;thermoluminescence
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发布时间：2023-12-11 - 摘要：To investigate the proliferative function of the major component of Salvia, the salvianolic acid B, on human chondrocyte cell line C28112 and to identify associated factors in regulatory signaling pathways, the study investigated the effective concentration of salvianolic acid B for chondrocyte growth in culture using MTS method and observe the cell division and the morphological changes by using Acridine orange fluorescent labeling of DNA and RNA to as well as detect protein expression levels of β-Catenin and the new types of cartilage growth factor cytokine-like 1 (CYTL-1) by Western Blotting (WB) method. The results showed that the absorbance values (A) in experimental group detected by the MTS methods were higher than the control group in all doses with statistically significance (p<001); In salvianolic acid B experimental group, splitting cell nucleus with more dual-nucleus cells were obviously seen, indicating more active cells in growth process; the semiquantitative Western Blot analysis showed that the CYTL-1 expression in salvianolic acid B experimental group was significantly upregulated compared to the control group, the expression of β-Catenin in experimental group showed a trend of upregulation. So, salvianolic acid B promoted the growth of human chondrocytes. The functional mechanism could be that the salvianolic acid B acted on the Wnt signal transduction pathway in chondrocytes, up-regulated the expression level of β-Catenin, activated the transcription of the target gene CYTL-1, and then stimulated its expression and release.
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发布时间：2023-12-11 - 摘要：The study was aiming for the Pharmacodynamic of Gangmei Ganmaoling granule fluid extract. By using pharmacological model, the toxicity, and antiinflammatory in mice, the antipyretic in rat, and analgesic effects of Gangmei Ganmaoling granule fluid extract were tested. The results showed that Gangmei Ganmaoling granule fluid extract has a low of toxicity . It can suppress the body temperature induced by 2,4-dinitrophenol in rats. The inflammatory swelling induced by xylene in ear of mice was alleviated. The capillary permeability induced by glacial acetic acid in mice was restrained. Analgesic study showed that the pain threshold of temperature stimuli was increased markedly in mice, the writhe incubation period was prolonged, and the number of writhe induced by abdominal of glacial acetic acid were decreased. In conclusion Gangmei Ganmaoling granule fluid extract was of low toxicity, with antipyretic, anti-flammatory and analgesic effects, which proved to be a safe and effective compound preparation of traditional Chinese medicine.关键词：Gangmei Ganmaoling Granule;the toxicity;antipyretic;antiinflammatory;analgesic
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发布时间：2023-12-11 - 摘要：This study investigated the polymorphism of Region V of the mitochondrial DNA and Ychromosome DYS287 sites in 9 ethnic groups of Guizhou to provide the referable molecular genetics data with related ethnic groups of Guizhou. Polymerase chain reactionpolyacrylamide SDS gel electrophoresis and Polymerase chain reactionagarose gel electrophoresis were applied to detect the polymorphism of 9bp deletion of mitochondrial DNA noncoding region and Ychromosome DYS287 sites. Two type of polymorphism in mitochondrial DNA were discovered：standard form and deletion form; the frequency of 9bp deletion of mtDNA in Gelao、She、Zhuang、Mulao、Maonan、Menggu、Hui、Qiang、Man people were: 26.6 %、25 %、20 %、18.3 %、13.3 %、10 %、8.3 %、6.7 %、5 %,respectively; two type of polymorphism in Ychromosome DYS287：YAP+and YAP-, the frequency of YAP+in Gelao、Maonan were: 20 %、1.67 %,respectively,others were 0.The data of polymorphism of Region V of mitochondrial DNA and Y-chromosome DYS287 sites were obtained in 9 ethnic groups of Guizhou and the genetic information were provided for ethnic groups.关键词：Guizhou;ethnic groups;mitochondrial;DNA;polymorphism
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发布时间：2023-12-11 - 摘要：The Bairong copper deposit of Tibet is a porphyry-type deposit discovered recently. The key for the further exploration is to identify burial depth, morphology and mineral body distribution of monzogranite porphyry in the northern part of the deep mine. An EH4 continuous conductivity profile was measured at the favorable metallogenic district in the northern part of Bairong copper deposit.The electrical difference in the mininginduced rock(ore) was used to interpret the comprehensive geology of quasi-two-dimensional contour section through two-dimensional qualitative and quantitative inversion combined with the geological model of the deposit. The results showed that the two-dimensional apparent resistivity - depth sectional drawing can clearly reflect the underground different geologic body of elaborate resistivity structure. The whole section can be divided into five kinds of different electrical body，among whichlayerⅣ of high resistance is speculated for concealed monzogranite porphyry body; Layer Ⅲof medium resistance is speculated for quartz monzonitic porphyry；Layer Ⅴof low resistance body consists of three parts, suggesting volcanic hydrothermal and porphyry Cu, Mo mineralization (body).关键词：EH-4 electromagnetic image system;mineral exploration;data processing and interpretation;Bairong copper deposition
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发布时间：2023-12-11 - 摘要：The total electron content (TEC) measured by GPS observations from the network of International GNSS Service (IGS) at the altitude of about 450 km in the 110°E longitude sector for more than a solar cycle term from January 2000 to December 2011 are used to study the northsouth asymmetry of the equatorial ionization anomaly (EIA). The parameters of the EIA crest obtained from the daytime TEC profiles for conditions of different solar activity have been used to study the solar cycle variations of EIA in the Southeast Asian region. Results show that the latitudinal position, occurrence time and strength of the EIA crest are found to be asymmetric about the magnetic equator and the conditions of solar activity have a remarkable effect on EIA crest and the northsouth asymmetry. The strength of EIA crest is obviously higher during periods of high solar activity, and the TEC average value of the EIA crest is obviously higher in the northern hemisphere during the daytime in all seasonal. The strength of the north crest is higher than that of the south crest in summer and autumn during low solar activity period, while smaller in winter.During high solar activity period, the occurrence time of the northern crest appears about 1 h later than that of the southern crest from June to August. And during low solar activity period, the occurrence time of the northern crest appears about 1 h earlier than that of southern crest in winter, while about 2 h later from May to September. With the solar activity increased gradually, the mean value of asymmetry index (Ia) increased obviously during winter solstice.关键词：ionosphere;equatorial ionization anomaly;north-south asymmetry;winter asymmetry
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发布时间：2023-12-11 - 摘要：Carboniferous Tournaisian C1t reservoir of F block in the Caspian Basin, deeply buried under gypsiferous rock, which seriouslyaffects the quality of seismic data, is difficult to be predicted by conventional methods with unfavorable factors of low seismic resolution and imaging quality, restricting the progress of the exploration. By the application of faciesconstrained reservoir prediction technology, 3 sedimentary facies were confirmed according to integrated analysis of seismic facies, logging facies and core data. Under the control of sedimentary facies, 2favorable reservoir zones were predicted by amplitude which is the most sensitive attribute for reservoir prediction. Application in favorable reservoir zone Ishows that 100% of the faciesconstrained reservoir prediction matches the realdrilling results.Therefore, under the constraints of sedimentary microfacies and sedimentary characteristics, seismic attributionscan be used to accurately predict and characterize complex reservoirs.关键词：facies-constrained;frequency division;reservoir prediction;hydrocarbon prediction
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发布时间：2023-12-11 - 摘要：The variations of 2-D MT field in anisotropic medium for conductivity were studied in this paper. The electromagnetic field was worked out with finite element method(FEM), and the apparent resistivity was obtained with the help of auxiliary field after variational problems in an anisotropic medium were solved. The differences of magnetotelluric field between anisotropic and isotropic media under TEzmode were discussed. Furthermore, the influence of dipping anisotropy and varying frequency was analyzed on the change of MT field. Finally, the characteristics of MT field response in the anisotropic media were obtained after discussing the effects of high resistance and low resistance on MT field and the impact of resistivity parallel to and perpendicular to the strike of structure.关键词：FEM;magnetotellurics;anisotropy medium;forward modeling
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发布时间：2023-12-11
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