最新刊期
卷 53 ， 期 5 ， 2014
- 摘要：In order to uncover the criminal gang, an approach of Crime Network Analysis based on association data model is proposed. The proposed method can discover all the members of a gang when a certain member is known, and it can also generate all the gangs based on known data source even none of the members are known. Especially, different models can be combined together to excavate the crime network. Experiments are executed based on the data of “communication” and “transfer” during 6 months. The results show that the proposed algorithm can demonstrate criminal gang no matter its members are known or not, and the same occurs as combining different models.关键词：association data;association data model;crime network;social network analysis
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发布时间：2023-12-11 - 摘要：A continuous-time ΣΔ ADC based on TDLTE terminals is implemented with 0.13 μm CMOS process to address the power consumption issue of TD-LTE terminals. The low-pass filter in conventional receiver is removed to save power consumption by using the proposed ADC. The proposed ADC is with 3rdloop filter, 3 bit quantizer, and compensates excess loop delay (ELD) in a compact way. The test results show the ADC achieves 66 dB dynamic range in TDLTE 20 MHz bandwidth, with 25.1 mA current consumption.关键词：TD-LTE;ΣΔADC;continuous time;excess loop delay (ELD)
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发布时间：2023-12-11 - 摘要：Content protection of fingerprint image is an important application field for information security, and robustness is a key techniques. An actualization method of block compressed sensing watermarking (BCSW) with variable sampling rates is proposed to aim at content security protection problem. Firstly, the watermark image of fingerprint is performed discrete wavelet transform (DWT), and divided into several sub block in which the block size can be adjusted according to structure features of the blocking image. Secondly, block-based compressed-sensing sampling is deployed independently within each subband of each decomposition level of a wavelet transform of an image. Finally, the formed watermark data are embedded into all sub-blocks of the LLn sub-band of the transformed host image by using quantization technique. Experimental results show that the introduction of compressed sensing theory improves the robustness and security of the protected fingerprint image.关键词：compressed sensing;fingerprint image;variable sampling rates;content protection;watermark
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发布时间：2023-12-11 - 摘要：Dynamic Fuzzy Neural Network (D-FNN), which basic idea is to construct a RBF neural network based on extension, could be seen as a TSK fuzzy system, as well as a Gaussian RBF neural network based on normalized. Within D-FNN algorithms, not only parameters could be adjusted in the learning process, but also the structure of fuzzy neural network could be automatically determined. Nonlinear parameters are directly decided by the training samples and Gaussian width, which only need one step training to achieve this goal. Due to the application of pruning strategies, network structure would not continue to grow, thus ensuring the generalization capability of the system. Simulations are performed on nonlinear dynamic system identification by using D-FNN, and the effectiveness and efficiency of D-FNN algorithm are proved by comparison with related algorithms.关键词：D-FNN;fuzzy rule;system identification;Radial Basis Function
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发布时间：2023-12-11 - 摘要：The consistency of electric vehicle Lithium-ion+Battery can affect the efficiency of electric vehicle directly. The consistency of battery must be monitored for the use and maintenance of battery. A consistency evaluation method based on standard deviation of cell voltage was proposed. The consistency of battery can be divided into four levels which correspond to four kinds of maintenance strategies. The electric vehicle Lithium-ion+Battery charge-discharge tests were used in the experiments, and the results show that the four consistency curves can be obtained by the method and it can provide a reference for the use and maintenance of battery.关键词：electric vehicle Lithium-ion+Battery;consistency;standard deviation;normal distribution
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发布时间：2023-12-11 - 摘要：In the fabrication process of interdigitated back contact (IBC) solar cell，one is using SiO2as a masking layer after boron diffusion and then diffusing phosphorus is used to form local back surface field (LBSF). Under the protection of SiO2the p-type emitter would stay unchanged and the area without SiO2will become n+LBSF. A gap covered with SiO2separates the emitter and LBSF. Thickness of thermal oxidation SiO2in different temperatures, from 0 nm to 124 nm, is investigated. Sheet resistance, minority carrier lifetime and diffusion profile by ECV before and after phosphorus diffusion are measured to see the effect of different silicon dioxide masking layers. With all these factors taken into consideration, the best thermal oxidation technique is determined for the following process of the IBC solar cell.关键词：IBC solar cell;SiO2mask;sheet resistance;minority carrier lifetime;ECV
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发布时间：2023-12-11 - 摘要：The temperature field will generate thermal stress in the concrete cylinder. The thermal stress for mutative axial temperature in the steady ax-symmetric temperature field is analyzed, then the full analytical solution is obtained and the solution of undetermined coefficents is discussed using the property of power and trigonometric function. Based on the results of temperature testing by temperature sensor deposited beforehand and analytical solution, the numerical examples about the Φ200×550 mm3concrete cylinder are given by Matlab. By the analysis, the conclusions can be got as the follows: the distribution of thermal stress in concrete cylinder wouldnt change, the values of stress would be in the same order of magnitude, and the range of stress would increase 40 percents nearly in the steady axsymmetric temperature field as temperature has transformed from 100 ℃ to 120 ℃.关键词：concrete;cylinder;thermal stress;analytical solution;temperature testing
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发布时间：2023-12-11 - 摘要：The proportional hazard model with Weibull frailty is used for analyzing right-censoring longitudinal survival data. Complex marginal integrals are avoided by using Hierarchal-likelihood to estimate covariate coefficients and prediction of random effects, the adjusted profile hierarchical-likelihood is taken to estimate the parameters of random factors'distribution. Simulation studies of comparing with other frailties including lognormal frailty and Gamma frailty are provided and the result indicates that the Weibull frailty performs very well. The examples for analyzing two real data sets are also presented, and the results indicate that the Weibull frailty model is at least as good as lognormal and Gamma frailty model, and the Weibull frailty model is more helpful to diagnose the heterogeneity.关键词：frailty model;Weibull Distribution;hierarchal-likelihood;proportional hazard;right censor
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发布时间：2023-12-11 - 摘要：With the comprehensive popularization of hospital informatization, each medical department need to develop their own front-end system, around the particularity of specialist service. According to the current number of hemodialysis patients, disease diversity, variety of dialysis machines and scheduling models, the optimization algorithm of automatic scheduling based on binary realizes intelligent scheduling function which is used binary number instead of the dialysis machine scheduling is designed. And combined with the management function, the web-based information management system for hemodialysis center is implemented. This system solves the complex manual scheduling and data collection difficulties of hemodialysis center, at the same time the decision support module can be more convenient to provide statistical analysis and assistant decision-making of all kinds of data for medical workers.关键词：hemodialysis;intelligent scheduling;WEB information system
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发布时间：2023-12-11 - 摘要：It's an important application for perfect matching counting theories in quantum chemistry, crystal physics and computer science. The research for perfect matching counting theories has a quite important theoretical value and realistic meanings. But the counting problem of perfect matching for general graphs has been proved to be NP—hard. Lovász and Plummer proposed a conjecture on this problem: every 2-edge-connected cubic graph has at least exponential perfect matchings. By applying differentiation, summation and re-nested recursive calculation, several counting formulas of the perfect matching for two specific types of graphs are given. And the results indicate that the conjecture of Lovász and Plummer is true in the case of these two types of graphs.关键词：perfect matching;linear recurrence relation;characteristic equation
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发布时间：2023-12-11 - 摘要：High-dimensional and imbalance data is a challenge for data mining. Balanced class distribution hypothesis leads to unsatisfied results of traditional feature selection algorithms on imbalanced data. For solving this problem, a new imbalanced feature selection algorithm IBRFVS, which uses the variable selection mechanism embedded in random forest, is constructed. IBRFVS construct vary decision trees on the balanced sampling data and get the feature importance measurements of individual decision tree by cross validation. The features importance list is decided by the weighted average of the decision tree weights and feature importance measurements, and the decision tree weights is decided by the consistent degree of the individual decision prediction and ensemble prediction. The random forest hyper parameter selection and preprocessing compare experiments on UCI dataset show that the performance of IBRFVS is more stable and prior than traditional feature selection algorithms when hyper parameter K is the square root of feature number, among four empirical parameters.
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发布时间：2023-12-11 - 摘要：The existence and permanence of the positive solutions for a one-prey and two-predators model with Crowley-Martin type functional response are considered. First, the bifurcation from a double eigenvalue for system is discussed by virtue of the space decomposition and the implicit function theorem, and the sufficient conditions for the existence of the positive steady-state solutions are obtained. Moreover, the sufficient conditions for the non-existence of the positive steady-state solutions are given. Finally, asymptotic behavior of the positive solutions of the parabolic system is investigated, and the sufficient conditions for extinction and permanence of the parabolic system are given by using the comparison theorem.关键词：predator-prey model;Crowley-Martin functional response;bifurcation;the implicit functional theorem;permanence
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发布时间：2023-12-11 - 摘要：USB is widely used in PC peripherals, and the increase of transmission data results in increasingly high requirement on transmission efficiency. However, there is a serious waste of USB bandwidth resources, due to the USB system software and characteristics of devices. A USB bulk transfer transaction scheduling method with SARSA learning algorithm for this problem, intelligently allocating the transactions in each frame based on current environment is designed. Simulation results show that this method significantly improves the utilization effectiveness of USB bandwidth and the throughput, compared to the method of the USB system, in the case of multiple bulk transfers.关键词：USB;SARSA;bulk transfer;utilization effectiveness of USB bandwidth
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发布时间：2023-12-11 - 摘要：In this work, spinel Fe3O4magnetic nano particles were synthesized by chemical co-precipitation method. The excess oleic acid was added during the initial stage of the reaction to prepare water-based ferrofluid under an alkaline condition. Subsequently, a novel and facile modified method were proposed by adding hydrochloric acid to adjust pH value or adding ethanol to successfully change the bilayercoated hydrophilic particles to hydrophobic ones. The coated particles were characterized by Fourier infrared spectrometer (FTIR), thermogravimetry analyzer (TG), transmission electron microscopy (TEM)and vibrating sample magnetometer (VSM). The results showed that the prepared water-based ferrofluid had the formation of inner layer chemical and outer layer physical adsorption by oleic acid and the particles'bilayer-coated structure was maintained by the acid modification through protonating the terminal carboxyl group, which had the maximum weight loss rate. The bilayer-coated Fe3O4particles were monodispersed in hexane indicated in TEM image. The stability of the ferroluid was much better than that of single coated particles because of the space steric effects'promotion caused by the bilayer-coated structure.关键词：protonated modification;bilayer coated;Fe3O4nano particles;oleic acid;hexane ferrofluid
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发布时间：2023-12-11 - 摘要：The diblock copolymer of Poly(ethylene glycol)-Cholic acid (PEG-CA) was synthesized and assembled to a novel polymeric micelles for drug delivery. Nuclear magnetic resonance (NMR) and infrared (FTIR) spectroscopy were used to analyze the structure of the polymer. Particle size and distribution of the selfassembled micelles were measured using Zeta-Plus particle size analyzer. The Doxorubicin (DOX) loading capacity of PEG-CA micelles was evaluated and potential ability for drug delivery in future clinical practice.关键词：poly(ethylene glycol) -cholic acid;drug delivery;anticancer drug
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发布时间：2023-12-11 - 摘要：The Tb-Fe-Co-B thin films were prepared through a non-aqueous electroless plating method at room temperature. The structures and magnetic properties of Sm-Fe-Ni-B alloys were characterized using SEM, EDS, XRD and VSM analyses. The results indicated that the coating was smooth. The density, deposition rate were improved with 3 g/L of Tb solution. An amorphous of Fe-Co-B was changed with a microcrystalline state of Tb-Fe-Co-B. The saturation magnetization rate and coercivity were enhanced in the meantime. In addition, the structure could be changed to produce a greater effect on the magnetic alloy at 600 ℃.关键词：Tb-Fe-Co;electroless plating;magnetism
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发布时间：2023-12-11 - 摘要：Phenolic acids in plant root exudates have stronger allelopathic activity, but fewer researches are focus on this area of mangrove plants, especially the status in situ-conditions. In this work, the roots, rhizosphere soil and non rhizosphere soil of six plants in Guangdong Zhanjiang National Nature Reserve of mangrove were sampled in situ. The total content of phenolic acids was measured using a potassium ferricyanide-ferric chloride colorimetric method. The results indicated that the content in roots was the highest in Rhizophora stylosa, the average value was 8 837.28 μg/g. The content of phenolic acids in rhizosphere soil and non rhizosphere soil were the highest in Bruguiera gymnorrhiza, the mean value were 13.20 μg/g and 20.12 μg/g, respectively. In total 18 samples, only 8 samples of the content in rhizosphere soils were higher than that of non rhizosphere soil. The content of phenolic acid in rhizosphere soil may be lower than that in non rhizosphere soil due to the comprehensive effect of microbial decomposition or soil adsorption and degradation. The release percent of phenolic acid from mangrove root was very low, only 0.050 4% in Rhizophora stylosa. These results are important meaning for clarifing the mangrove ecological mechanism especially the mechanism of root microecology.关键词：mangrove plants;phenolic acid;root exudates;rhizosphere soil;nonrhizosphere soil;content;in-situ
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发布时间：2023-12-11 - 摘要：There are no relevant remediation standards to conduct the work for remediation of petroleum hydrocarbon contaminated soils in China. Thus, the researching methods for derivation and enactment of remediation criteria and standards for hydrocarbon contaminated soils in foreign countries are of significance for methodological references. In this work, the connotation of remediation criteria/standards for petroleum contaminated soils was briefly expounded from two aspects, namely, the meaning of the remediation criteria/standards and the classification method of petroleum hydrocarbons. Then, the tiered methods from foreign countries were introduced, followed by the summarization of application of risk assessment and their relevant models, the research about the analytical methods and the indicators/surrogates.At last, the general researching methods of remediation criteria/standards for petroleum contaminated soils were concisely concluded, and the further research in this direction was prospected.关键词：petroleum hydrocarbon;contaminated soil;remediation criteria;cleanup standard;ecological risk;chemical-specific
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发布时间：2023-12-11 - 摘要：In this paper, we concentrated on masculinization of larvae Nile Tilapia（Oreochromis niloticus）by immersion the larvae in androgens MT（17α-methyltestosterone）or MDHT（17α-methyldihydrotestosterone）. The three factors were considered: treatment period（1, 7, 13 DPH, Days Post Hatching）, hormone dose（200, 600, 1 800, 5 400 μg·L-1）, and treatment duration（2, 4, 8 h）. All these three factors were taken into account by simple comparison orthogonal experimental design. The main results are as follows: the 7 DPH larvae induced by MT at a dose of 600 μg·L-1 with 4 h treatment duration is the best result of masculinization, male rate is 98.81%, while at a dose of 1 800 μg·L-1or 5 400 μg·L-1, male rate greatly decreased（P＜0.05）; 600 μg·L-1 or 1 800 μg·L-1dose of MDHT present the best results of masculinization, male rate is 98.34% and 98.39% respectively, at a dose of 200 μg·L-1or 5 400 μg·L-1, male rate are not significantly decreased（P＞0.05） When 7 DPH larvae were induced by MT at a dose of 600 μg·L-1, 4 h is the best treatment duration, 8 h presents greatly decreased result（P＜0.05）; When MDHT was used, three treatment durations（2, 4, 8 h）got consistent results（P＞0.05）. The conclusion is that MT and MDHT can both achieve masculinization goals for application of production, but MDHT is more stable and show a better application value.关键词：Oreochromis niloticus;masculinization;immersion;MT;MDHT
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发布时间：2023-12-11 - 摘要：Daily precipitation and mean temperature data of 18 meteorological stations over the Beijiang River Basin of Guangdong for the last fifty years were analyzed to classify anomalously dry conditions using the standardized precipitation and evapotranspiration index (SPEI). In this study，drought variables (drought duration, drought severity and drought severity peak) were identified using run-length theory, 11 probability distribution functions were adopted to analyze the probability behaviors of drought severity and drought severity peak at 18 meteorological stations. The L-moment technique is used to estimate the parameters of the probability functions, the Kolmogorov-Smirnov method (K-S) is accepted to evaluate the goodness-of-fit of the probability functions and evaluate the tenyear return periods values. Based on the Genest-Rivest method and the tail dependency of random variable, GH copula that has up tail dependency is used for drought variable connect function. The Kendall rank correlation coefficient method is used to estimate the parameters of GH copula function. Then we comprehensively analyze the spatial variability of joint probability distribution of two indices. The spatial variability of probability distribution of one drought variable and joint distribution of two drought variables can provide the scientific basis for analysis of the local water volume balance and reduce drought disaster risk.关键词：Copula function;SPEI;drought frequency analysis;Beijiang river basin;Guangdong
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发布时间：2023-12-11 - 摘要：Water resources renewability (WRR) determines water resources sustainability. Facing the increasing serious water resources pressure over the Pearl River Delta (PRD), this paper, constructed a multi-hierarchy and multi-index WRR assessment system and developed an assessment model based on variable fuzzy sets theory, by which the WRR level of PRD was assessed. The results show that the WRR levels of nine cities in the PRD all belong to level II, with Shenzhen and Zhaoqing being the strongest while Foshan and Dongguan being the weakest. Particularly, the WRR levels of Zhongshan, one of the nine cities, are determined by its social WRR levels and go down first then up from 2001 to 2012. The assessment results of different methods show that Grey Relation Analysis and Fuzzy Comprehensive Evaluation have almost the same results. Variable Fuzzy Evaluation gives results with one level lower than those of the above two methods, since it calculates membership grades more finely and inclines to give lower level assessment. Genetic Projection Pursuit Method produces unreasonable results when sample data vary tremendously, thus making it not applicable for assessment of WRR levels of the nine cities in the PRD. In addition, a stricter standard system was constructed based on national data and data of the PRD. Under that system, the WRR levels of nine cities of the PRD were all assessed as level III. The stricter assessment results are likely to promote measures to increase WRR of the PRD.关键词：water resources;water resources renewability assessment;variable fuzzy sets theory;Pearl River Delta.
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发布时间：2023-12-11 - 摘要：Temporal and spatial variations of soil moisture in Shanxi Province are analyzed by using Inverse Distance Weighted (IDW) method with ArcGIS software package, based on soil moisture and precipitation data from 64 monitoring stations during 2003-2012..The annual and seasonal variations in soil moisture are obtained, and influences of precipitation and temperature changes on soil moisture are investigated using correlation analysis technique. The results indicate that soil moisture is high in the southeast Shanxi, and low in the north and south parts of the Shanxi province. All soil moistures at 10, 20 and 40 cm soil depth show similar variation feature to spatial patterns, but with a less variability in soil moisture at lower soil layer. Moreover, soil moisture tends to increase from the upper to the lower soil profile. There are no clear interdecadal change but obvious seasonal change in soil moisture, decreasing from March, becoming increase in June, and then decreasing again from October. Precipitation plays a key role in spatiotemporal variations of moisture and influences of temperature on soil moisture are moderate.关键词：soil moisture;temporal and spatial variation;precipitation;Shanxi Province
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发布时间：2023-12-11 - 摘要：Based on the dolomite karst development environment, geomorphology characteristics and evolutionary features, Shibing Karst was compared with Huanjiang Karst, aiming to determine whether Shibing Karst is worth nominating to South China Karst world heritage. The dolomite karst in Shibing has different development environment, geomorphology characteristics and evolutionary features comparing to that in Huanjiang. The Shibing dolomite karst has occupied an important position and value in karst morphological spectrum of South China, characterized by unique morphogenetic stratum structure- pure, thin and fine-grained dolomite, typical dendritic fengcong-gorge karst landscape and special dolomite open-style evolution model. Therefore, nomination of Shibing Karst would make extremely important supplement and perfection of dolomite karst to South China Karst worle heritage.关键词：world heritage;geomorphologic value;dolomite kasrt;comparison;Huanjiang;Shibing
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发布时间：2023-12-11 - 摘要：In order to study the change rule of specific surface area (SSA) and cation exchange capacity (CEC) of different mixing ratio of lime-stabilized loess in the same curing time, the methylene blue spot method is used to test specific surface area and cation exchange capacity of the solidified loess in 7 days curing, calculating the activity and classification value of the stabilitied loess according to the specific surface area and clay content. The results show that specific surface area, ion exchange capacity, active index and classification value of the stabilized loess gradually reduce with the increment of quicklime mixing ratio, when the mixing ratio is 5% SSA and CEC show a turning point. The relation of specific surface area, cation exchange capacity and active index has been discussed. These results reveal that the formation of poly particle and increase of the macropore in the stabilized loess reduce the specific surface area and cation exchange capacity of natural loess. The advantages in pore size and the changes in porosity may be the reasons why SSA and CEC show a turning point with a mixing ratio of 5%.关键词：stabilitied loess;specific surface area;cation exchange capacity;activity;classification value
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发布时间：2023-12-11
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