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The two-grid algorithm of the finite volume element method for second-order indefinite elliptic problems DAI Zhen-xiang J4    Abstract （1658）      PDF（pc） （240KB）（34856）       Save The two-grid algorithm of the finite volume element method for second-order indefinite elliptic problems in R2 was presented ,based on the P1 nonconforming element.The following error estimated in the H1-norm between the solution of the two-grid and the finite volume element appoximation of the elliptic problem were derived::‖uh-uh‖1,h≤CH2‖f‖1,‖u-uh‖1,h≤C(h+H2)‖f‖1. Related Articles | Metrics

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JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    1953, 00 (06): 1-.   Abstract （269）      PDF（pc） （3108KB）（2160）       Save Related Articles | Metrics

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A system of monitoring and protecting Android privacy leakage JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2016, 51 (9): 59-67.   DOI: 10.6040/j.issn.1671-9352.1.2015.293 Abstract （2470）      PDF（pc） （3349KB）（3630）       Save In order to protect the data of Android operating system, we present a system called FlowMonitor to monitor and protect privacy flow based on Android. FlowMonitor adds taint marks and identity tags onto data. Moreover, it is a real-time, dynamic monitoring system. In order to avoid leaking private data by collusion attack, it uses the mechanism of taint's identity authentication based on the idea of RBAC, and finds all probable malicious applications. Based on open and closed policies, labels were designed for each data to control the use of private data. The user can control applications using private data based on their choices. Evaluation results show that Flowmonitor out performs taint Droid. It can not only find out all probable malicious applications which steal private data by collusion attack, but also control applications using each private data. Extensive experimental results demonstrate that FlowMonitor effectively protects the user privacy. Reference | Related Articles | Metrics

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Uniqueness of positive solutions of singular p-biharmonic equations with Hardy terms JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (6): 75-80.   DOI: 10.6040/j.issn.1671-9352.0.2018.496 Abstract （1057）      PDF（pc） （369KB）（1404）       Save We study a class of singular p-biharmonic equations with Hardy terms. The existence and uniqueness of the positive solution for above problem is obtained by minimization method. Reference | Related Articles | Metrics

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Order of matching energy and Hosoya index of Q-shape graphs LIU Xiao-hua, MA Hai-cheng JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2018, 53 (8): 61-65.   DOI: 10.6040/j.issn.1671-9352.0.2017.280 Abstract （2001）      PDF（pc） （336KB）（716）       Save The Q(s,t)(s≥2t≥1)is the graph with s+t+1 vertices. A complete order of matching energy of the Q-shape graphs is given. As a consequence,the order of Hosoya index also be obtained. Reference | Related Articles | Metrics

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A characterization of ξ-skew Jordan derivable mappings on factor von Neumann algebras ZHANG Fang-juan JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2020, 55 (7): 32-37.   DOI: 10.6040/j.issn.1671-9352.0.2020.100 Abstract （940）      PDF（pc） （818KB）（485）       Save Let R be a factor von Neumann algebra with dim R>1. For given complex number ξ and ξ ≠0, if a map δ:R→R satisfies δ((A·B)ξ)=(δ(A)·B)ξ+(A·δ(B))ξ for all A,B∈R, δ is an additive *-derivation and δ(ξA)=ξδ(A). In particular, if the von Neumann algebra R is infinite type Ⅰ factors, a concrete characterization of δ is given. Reference | Related Articles | Metrics

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Some new characterizations of generalized and hypergeneralized projectors LUO Gao-jun, ZHOU Liang, ZUO Ke-zheng JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2016, 51 (4): 43-48.   DOI: 10.6040/j.issn.1671-9352.0.2015.114 Abstract （1010）      PDF（pc） （609KB）（1009）       Save The paper mainly uses the decomposition of the ΣKL of the matrix to give several new characteristics of generalized projectors(A2=A*)and hypergeneralized projectors(A2=A†), which generalized some related results of Baksalary. Reference | Related Articles | Metrics

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Synthesis and characterization of a novel coordination complex ［Ni(Hpdc)(2,2’-bipy)(H2O)2］·H2O HAN Lu1, SHENG Dao-peng1, WEI Hui-ying1, YANG Yan-zhao1,2 * J4    2012, 47 (5): 9-12.   Abstract （1740）      PDF（pc） （867KB）（1914）       Save The  compound, ［Ni(Hpdc)(2,2’-bipy)(H2O)2］·H2O (H3pdc=3,5pyrazoledicarboxylic acid, 2,2’-bipy=2,2’-bipyridine), was prepared under hydrothermal conditions. The structure of the coordination complex was determined by Xray single crystal diffraction and characterized by elemental analysis, IR spectrum and thermogravimetric analysis. The coordination complex crystallized in the triclinic system, with space group Pī. The metal ion was located in the centre of a distorted octahedron. The Ni(II) ion was sixcoordinated with three oxygen atoms and three nitrogen atoms. The four molecules that built  up a cell unit were connected via hydrogen bonds while no π-π interactions were observed between aromatic rings. Related Articles | Metrics

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Heterogeneous network representation learning based on metapath attribute fusion Jinghong WANG,Zhibing WU,Peng HUANG,Jiateng YANG,Bi LI JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2024, 59 (3): 1-13.   DOI: 10.6040/j.issn.1671-9352.7.2023.787 Abstract （137）   HTML （0）    PDF（pc） （5926KB）（187）       Save Focusing on the research on representation learning of information networks, a metapath attribute fusion graph neural network (MAFGNN) based on metapath information fusion is proposed, which is to integrate the neighbor information of the target node, including the metapath information, into the node before introducing the metapath in the heterogeneous network to achieve the fusion of target node and neighbor information. This method first converts the attribute features of different types of nodes into dimensions to facilitate subsequent fusion operations. The fusion operation of target node information is completed by calculating the weight values of target nodes and neighbor nodes. Then target nodes are fused according to specific metapaths, and finally different semantic information is fused between different metapaths. Experiments on multiple heterogeneous information datasets show that the MAFGNN model has the best performance and more accurate prediction results than the most advanced benchmark experiments in dealing with heterogeneous network node embedding. Table and Figures | Reference | Related Articles | Metrics

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Heuristic construction method of fuzzy concept set and its recommended application Zhonghui LIU,Shuai JIANG,Fan MIN JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2024, 59 (3): 14-26.   DOI: 10.6040/j.issn.1671-9352.7.2023.9950 Abstract （86）   HTML （1）    PDF（pc） （1376KB）（152）       Save Aiming at the problem that fuzzy formal concept analysis is difficult to apply to large-scale datasets in recommendation applications, a recommendation method based on a heuristic construction of fuzzy concept set is proposed. Sub-contexts are constructed for each user based on the similarity between users. Then, new heuristic information is used on the sub-contexts to generate fuzzy concepts with users and items as clues, respectively. Finally, using the internal information of fuzzy concepts, a recommendation confidence integrated with user weights is designed to achieve personalized recommendations for users. The experimental results on six real datasets show that the proposed method has higher recommendation efficiency, and can achieve better recommendation results on sparse data sets compared with classical collaborative filtering algorithms. Table and Figures | Reference | Related Articles | Metrics

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Pottiaceae in Shandong Province, China LI De-li, REN Zhao-jie, YAN Li-mei, BIAN Xin-yu,ZHAO Zun-tian JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2016, 51 (3): 11-18.   DOI: 10.6040/j.issn.1671-9352.0.2015.401 Abstract （1282）      PDF（pc） （1051KB）（1386）       Save Based on the identification of about 5500 specimens collected from Shandong Province, 79 species, 3 varieties and 24 genera of Pottiaceae in Shandong Province are reported. Among them, Weissia muhlenbergiana (Swartz)W. D. Reese & B. A. E. Lemmon is found from China for the first time, while 3 genera, Chenia R. H. Zander, Gymnostomiella M. Fleisch. and Tuerckheimia Broth., and 28 species are reported from Shandong Province for the first time. At the same time, the species composition based on the specimens collected before and after 2000 are compared, it is found that the difference is obvious, and the reasons are given. This study aims to clarify the species diversity of Pottiaceae in Shandong Province. At the same time, the study can provide new data for the bryophyte researches of China. Related Articles | Metrics

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Advances of gene knockout in mice ZHANG Jian, YANG Xiao-mei*, GAO Jian-gang* JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2011, 46 (10): 183-196.   Abstract （1760）      PDF（pc） （1176KB）（3090）       Save With the successful completion of Human Genome Project (HGP),the biological research of postgenome era has a urgent need for an effective gene function analysis. Application of knockout mouse model provides a strong support for the study of gene function and the search for new therapeutic interventions in human disease. As two different techniques, gene targeting and gene trapping are producing knockout mice from embryonic stem cells (ES cells).The characteristic of gene trapping is highthroughput, random, and sequence tagged,while gene targeting is a specific gene knockout. Two decades ago, the first gene targeting and gene trapping mice were generated. In recent years, new tools for gene targeting and gene trapping are emerging, and the related organizations have been formed. These organizations can knock out genes in the mouse genome using these two methods. The international gene trap consortium (IGTC) and the knockout mouse project (KOMP) have begun to create a worldwide resource for research facilities, and plan to knock out all the mouse genes. KOMP organizers consider it as important as the HGP. From conventional gene targeting to high throughput conditional gene targeting, gene targeting methods have changed. The combined advantages of trapping and targeting enhance the gene trapping spectrum and gene targeting efficiency. As a newly developed insertional mutation system, transposons in trapping genes have more advantages than retrovirus. Emergence of the international knockout mouse consortium (IKMC) is the beginning of global cooperation. The organization is committed to systematically knock out all genes in the mouse genome, and then to carry out functional genomics studies. Related Articles | Metrics

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The quantitative analysis of the impact of financial news on stock market ZHAO Li-li, ZHAO Xi-qian, YANG Juan, WANG Tie-jun, LI Qing* J4    2012, 47 (7): 70-75.   Abstract （1673）      PDF（pc） （1192KB）（1912）       Save  Text mining and support vector regression techniques were adopted to quantify the impact of financial news on Chinese stock market. Then  the multiple regression of econometrics was used to analyze how the online financial news affected stock market returns systematically. It focused on the impact intensity and time of online news on the stock market, and its impact on listed firms with different scales. Experimental results show that firms with Shenzhen Stock Exchange are more affected by the Internetbased financial news than those of Shanghai Stock Exchange and firms with smaller size tend to have a stronger impact on the movements of Chinese stock market. Our findings include that Internet-based financial news contains hard-to-quantify information of firms, which investors incorporate into stock prices timely. Related Articles | Metrics

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Tail dependence analysis based on tail sample data LI Shu-shan JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2014, 49 (12): 49-54.   DOI: 10.6040/j.issn.1671-9352.0.2014.156 Abstract （1819）      PDF（pc） （710KB）（2035）       Save Tail dependence is the nature of the tail to the joint distribution of the two random variables. Be directed against tail dependence analysis, two concepts of order statistics for 2-dimension random vector were proposed and an idea was advanced to estimate the tail dependence coefficient by fitting Copula function using tail sample. Then the method of parameter estimation and fitting tests for the tail based on tail sample date and the corresponding estimate method for tail dependence coefficient were also discussed. A Monte Carlo simulation was given to illustrate the validity of the method given. Finally the tail dependence between the SHI and the SZI was analyzed. Reference | Related Articles | Metrics

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Optimization of hydrogeological parameters based on improved butterfly optimization algorithm Xiuxi WEI,Maosong PENG,Huajuan HUANG JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2024, 59 (3): 37-50.   DOI: 10.6040/j.issn.1671-9352.7.2023.3667 Abstract （68）   HTML （0）    PDF（pc） （5875KB）（134）       Save In order to solve the problems of insufficient accuracy of hydrogeological parameters and low efficiency of traditional routing methods, an optimization strategy of hydrogeological parameters based on golden sine weighted butterfly optimization algorithm (GSWBOA) is proposed. Firstly, the golden sine operator is introduced in the global and local search phase of butterfly optimization algorithm to reduce the solution space of the algorithm. Secondly, adaptive weights are introduced to adjust the individual moving step size and search direction in the later stage of the algorithm. The comparison test results of 6 benchmark test functions show that the GSWBOA has higher optimization accuracy and faster convergence. The optimization strategy is applied to the optimization of hydrogeological parameters water conductivity coefficient and water storage coefficient to achieve the minimum depth reduction error, and the optimization strategy is compared with particle swarm optimization algorithm, wiring method and other optimization strategies. The results show that the golden sinusoidal weighted butterfly optimization algorithm can effectively optimize the hydrogeological parameters, improve the calculation performance of Theis formula, and obtain a smaller drawdown error, which provides a new method for the subsequent pumping test. Table and Figures | Reference | Related Articles | Metrics

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Characterization and structural control of metalbased nanomaterials YANG Jun JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2013, 48 (1): 1-22.   DOI: 10.6040/j.issn.1671-9352.9.2012.001 Abstract （1417）      PDF（pc） （6800KB）（2395）       Save The common analytical and characteristic techniques including UV-visible spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and scanning transmission electron microscopy (STEM) are briefly introduced in this review article. In addition, in wetchemistry based syntheses, the approaches used to tune the structure of metal-based nanomaterials are categorized and discussed. Related Articles | Metrics

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Generalization of Gronwalls inequality and applications WANG Xiao-huan, LÜ Guang-ying, DAI Li-jie JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2022, 57 (6): 94-101.   DOI: 10.6040/j.issn.1671-9352.0.2021.451 Abstract （970）      PDF（pc） （408KB）（763）       Save The classical Gronwalls inequality is generalized and a Gronwalls inequality with multiple singularity points is obtained. Then the existence and uniqueness of solutions to stochastic fractional order differential equations is obtained by using the obtained inequality. Reference | Related Articles | Metrics

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A sentiment analysis method based on a polarity lexicon ZHANG Cheng-gong 1, 2, LIU Pei-yu1, 2*, ZHU Zhen-fang1,2, FANG Ming1,2 J4    2012, 47 (3): 47-50.   Abstract （1954）      PDF（pc） （1026KB）（5059）       Save A polarity lexicon is the foundation of sentiment analysis and orientation analysis. An overall and effective polarity lexicon was constructed, including base lexicon, domain lexicon, network lexicon and modifier lexicon. The influence of modifiers to polarity words was studied. A sentiment analysis method based on a polarity lexicon was proposed, in which the modifiers and polarity words were combined into polarity phrases, and the phrase was used as the basic unit to compute the polarity of sentences and texts. Experimental results showed that the effect of orientation analysis using polarity lexicon raised in this paper was good. Related Articles | Metrics

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The solution of the time-fractional model of heat transport in complex human tissue ZHAI Ru-kun, JIANG Xiao-yun J4    2012, 47 (6): 1-4.   Abstract （1087）      PDF（pc） （816KB）（2137）       Save A fractional Pennes bioheat transfer equation is established. By applying the finite Fourier sine transformation, Laplace transformation and their corresponding inverse transforms, the analytic solution of the fractional Pennes bioheat transfer equation is obtained. And the expression in the form of generalized Mittag-Leffler function is given. Finally, the integer-order as a particular case is discussed. Related Articles | Metrics

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Research advances of novel nonlinear optical crystals based on second-order Jahn-Teller effects (SOJT) ZHANG Jun-jie, ZHANG Zhong-han, TAO Xu-tang* JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2011, 46 (10): 99-120.   Abstract （3005）      PDF（pc） （5876KB）（2735）       Save Explorations of new inorganic second-order nonlinear optical (NLO) materials is one of the current frontier topics due to their optoelectronics application such as frequency shifting, optical modulating, telecommunications and signal processing. Since 1998, a series of noncentrosymmetric (NCS) and polar oxides containing cations susceptible to second-order Jahn-Teller (SOJT) distortions, specifically, octahedrally coordinated d0 transition metals (TMs: Mo6+,W6+,V5+,Nb5+,etc.) and cations with stereochemically active lone pairs (SCALP, e.g. I5+, Te4+, Se4+, Sn2+, etc.), were successfully synthesized. Many of these materials exhibit large powder second-harmonic generation (SHG) efficiencies (> 400×α-SiO2). This paper reviews the progress on the materials in the past decade, including the search for new materials and crystal growth. The materials are divided into three categories: NCS oxides containing one kind of SOJT cations (d0 or SCALP), NCS oxides containing both kinds of SOJT cations, and NCS oxides containing SOJT cations and other NCS building units such as borate πorbital systems, tetrahedral groups and d10 transition metal cations (Zn2+, Cd2+, Sn4+, etc.). Related Articles | Metrics

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Inward-recursion information and characteristics-identification of inward-recursion binary tree LI Yu-ying1,2, LIN Hong-kang1,2 J4    2012, 47 (8): 86-91.   Abstract （901）      PDF（pc） （986KB）（1822）       Save Introducing the structure of tree into the recursion structure of the inward-recursion information,  the concept of inward-recursion binary tree is proposed. The structure and the characteristics of the tree are obtained. Also, the inward-recursion degree and the recursive loss degree are defined. The existence theorem of the inward-recursion binary tree, the existence and uniqueness theorem of the full binary tree for the inward-recursion binary tree, the theorem of the complete binary tree for the inward-recursion binary tree are given, including the identification theorems and the identification criterion of nodes for the inward-recursion binary tree. The inward-recursion binary tree is an important organization structure for the inward-recursion information. The research way and results provide a new method for information processing which has the characteristics of inward-recursion. Related Articles | Metrics

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Novel synthesis of C-terminal polypeptides by ISPPS method CHEN Lei, JIN Zhi, LIU Qiang, WANG Ming, WANG Pu* JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2014, 49 (1): 31-35.   DOI: 10.6040/j.issn.1671-9352.0.2013.235 Abstract （1227）      PDF（pc） （1456KB）（1710）       Save A facile approach for the preparation of polypeptide C-terminal derivatives by inverse solid phase peptide synthesis (ISPPS) was developed. This novel method combines both advantages of Fmoc-SPPS and TAEC technology, utilizes fewer functional group protection steps. In addition, the reaction can be carried out at room temperature under mild conditions and be easily monitored, and the working-up is simple and efficient. This method is complementary to the direct solid phase peptide synthesis. Several polypeptides as well as their C-terminal derivatives were efficiently prepared by this novel ISPPS method. Related Articles | Metrics

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Grey wolf optimization algorithm based on multi-strategy combination and its application Hongwu QIN,Lizheng WANG,Yu FU,Muxuan SUI,Binggao HE JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2024, 59 (3): 51-60.   DOI: 10.6040/j.issn.1671-9352.7.2023.4633 Abstract （89）   HTML （1）    PDF（pc） （5268KB）（105）       Save The standard grey wolf optimizer (GWO) algorithm has issues such as difficulty balancing local exploration and global development. A multi-strategy grey wolf optimization algorithm (MSGWO), based on the fusion of various strategies, is presented to address such problems. First, the grey wolf algorithm introduces the Tent map and a nonlinear convergence factor. Then, to coordinate attempts in the GWO optimization process, the paper applies three learning strategies: extensive learning, elite learning, and coordinated learning. Finally, the paper uses roulette wheel for strategy selection to obtain more diverse wolf positions and globally representative individuals and utilizes benchmark function testing to compare algorithm variations. The outcomes demonstrate that the MSGWO algorithm has a faster convergence speed and a good balance between local development and global search. Based on this, the echo state networks (ESN) hyperparameter for regression prediction is optimized using the MSGWO method. The experiment demonstrates that the MSGWO algorithm performs optimally with an average absolute percentage error of 0.38 percent and a fitting degree of 0.98. Table and Figures | Reference | Related Articles | Metrics

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BERT-IDCNN-CRF for named entity recognition in Chinese Ni LI,Huan-mei GUAN,Piao YANG,Wen-yong DONG JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2020, 55 (1): 102-109.   DOI: 10.6040/j.issn.1671-9352.2.2019.076 Abstract （4346）   HTML （137）    PDF（pc） （2001KB）（1978）       Save The pre-trained language model, BERT (bidirectional encoder representations from transformers), has shown promising result in NER (named entity recognition) due to its ability to represent rich syntactic, grammatical information in sentences and the polysemy of words. However, most existing BERT fine-tuning based models need to update lots of model parameters, facing with expensive time cost at both training and testing phases. To handle this problem, this work presents a novel BERT based language model for Chinese NER, named BERT-IDCNN-CRF (BERT-iterated dilated convolutional neural network-conditional random field). The proposed model utilizes traditional BERT model to obtain the context representation of the word as the input of IDCNN-CRF. At training phase, the model parameters of BERT in the proposed model remain unchanged so that the proposed model can reduce parameters training while maintaining polysemy of words. Experimental results show that the proposed model obtains significant training time with acceptable test error. Table and Figures | Reference | Related Articles | Metrics

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Entity disambiguation method based on graph attention networks Zequn NIU,Xiaoge LI,Chengyu QIANG,Wei HAN,Yi YAO,Yang LIU JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2024, 59 (3): 71-80, 94.   DOI: 10.6040/j.issn.1671-9352.1.2022.4484 Abstract （80）   HTML （1）    PDF（pc） （4157KB）（111）       Save We propose an entity disambiguation method based on graph attention networks for semi-structured knowledge base data. First, a global knowledge graph is constructed from the semi-structured knowledge base, and the entity reference items are embedded by Bert pre-trained model meanwhile. Next, graph attention networks which leverages masked self-attention layers is applyed on candidate entity nodes of global knowledge graph to fetch a vector of node level. Furtherly, we com pute similarity scores rank between the entity reference items and the candidate entity to complete the task of entity disambiguation. The experimental results on CCKS2019 dataset achieve state-of-the-art. Table and Figures | Reference | Related Articles | Metrics

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Multi-label classification for medical text based on ALBERT-TextCNN model ZHENG Cheng-yu, WANG Xin, WANG Ting, DENG Ya-ping, YIN Tian-tian JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2022, 57 (4): 21-29.   DOI: 10.6040/j.issn.1671-9352.7.2021.083 Abstract （2076）      PDF（pc） （1552KB）（867）       Save Aiming at the problem of existing static word vector representation methods such as Word2Vec and Glove cannot solve the problem of complete text semantics, combined with the ALBERT pre-trained language model and the TextCNN convolutional neural network, a deep neural network model for multi-label medical text classification named ALBERT-TextCNN is proposed. The model use the ALBERT pre-training language model for dynamic word vector representation to obtain a more efficient text vector representation through its internal multi-layer bidirectional Transfomer structure, and introduce the TextCNN convolutional neural network model to construct a multi-label classifier for training to extract semantic information features at different levels of abstraction. The performance of the algorithm is tested on the Chinese health question data set. The experimental results show that the overall F1 value of the model reaches 90.5%, which can effectively improve the multi-label classification effect of the medical text. Reference | Related Articles | Metrics

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Existence and uniqueness of solutions of a class of singular parabolic equations YUN Dong-fang, HUANG Shu-xiang J4    2012, 47 (2): 1-7.   Abstract （875）      PDF（pc） （809KB）（1945）       Save Related Articles | Metrics

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Security analysis of the eCK model NI Liang1,2,3, CHEN Gong-liang3, LI Jian-hua3 J4    2013, 48 (7): 46-50.   Abstract （1603）      PDF（pc） （929KB）（2411）       Save Authenticated key agreement (AKA) protocol should capture desirable security properties as many as possible. As a formal method recently proposed to design and analyze two-party AKA protocols, the eCK model is currently receiving more and more attention, and the exact security guarantees that can be provided by this model are worthy of in-depth research. Hence, the relationship between the eCK model and the basic desirable security properties for AKA protocols is analyzed in detail. The conclusions indicate that AKA protocols with provable security in the eCK model capture most basic desirable security properties. Thereafter, the advantages and disadvantages of the eCK model are also summarized. Related Articles | Metrics

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Existence of nontrivial solutions for boundary value problems of fractional differential equations MA Yan, ZHANG Ke-yu JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2015, 50 (05): 68-73.   DOI: 10.6040/j.issn.1671-9352.0.2014.317 Abstract （1318）      PDF（pc） （696KB）（759）       Save By applying the theory of Leray-Schauder degree, the existence of nontrivial solutions for the boundary value problems of fractional differential equations  is considered under some conditions concerning the first eigenvalue corresponding to the relevant linear operator.Here α∈(2,3]is a real number, D0+α is the standard Riemann-Liouville fractional derivative of order α. Reference | Related Articles | Metrics

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HPLC separation of enantiomers of dracocephins A LI Chao, ZHAO Li-juan, ZHANG Yao, REN Dong-mei* JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2014, 49 (1): 36-38.   DOI: 10.6040/j.issn.1671-9352.0.2013.419 Abstract （1261）      PDF（pc） （1255KB）（1489）       Save To establish a direct enantioseparation method by HPLC on immobilized amylose-based chiral stationary phase for the chiral separation of the enantiomers of dracocephins A. The separation was carried out using a Chiralpak IA column (4.6mm×250mm, 5μm) in combination with n-hexane-ethyl acetate (10∶90) as mobile phase. The flow rate was 1.0mL·min-1 and detection wavelength was 290nm, whilst the column temperature was room temperature. The established chromatographic method was effective for the simultaneous separation of the two pairs of enantiomers of dracocephins A. The elution order was determined by coupling HPLC-CD detection and comparison with each single enantiomer. Immobilized amylosebased chiral stationary phase is suitable for the enantioseparation of dracocephins A. Related Articles | Metrics

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A bilingual word alignment method of Vietnamese-Chinese based on deep neural network MO Yuan-yuan, GUO Jian-yi, YU Zheng-tao, MAO Cun-li, NIU Yi-tong JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2016, 51 (1): 77-83.   DOI: 10.6040/j.issn.1671-9352.3.2014.289 Abstract （1371）      PDF（pc） （1557KB）（1335）       Save It is difficult to achieve auto-alignment between Vietnamese and Chinese, because their syntax and structure are quite different. In this case, we present a novel method for the Vietnamese-Chinese word alignment based on DNN(deep neural network). Firstly, we should convert Vietnamese-Chinese bilingual word into word embedding, and as the input within DNN. Secondly, DNN-HMM word alignment model is constructed by expanding HMM model, which also integrating the context information. The basic model of the experiments are HMM and IBM4. The results of large-scale Vietnamese-Chinese bilingual word alignment task show that this method not only significantly improved its accuracy and recall rate than the two basic models, but also greatly reduced word alignment error rate. Reference | Related Articles | Metrics

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Superconvergence and extrapolation of a lower order mixed finite method for nonlinear fourth-order hyperbolic equation ZHANG Hou-chao, ZHU Wei-jun, WANG Jun-jun JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2015, 50 (12): 35-46.   DOI: 10.6040/j.issn.1671-9352.0.2014.424 Abstract （1285）      PDF（pc） （688KB）（902）       Save With the help of the bilinear element Q11 and the Q01×Q10 element, a lower order conforming mixed finite element approximation scheme is proposed for nonlinear fourth-order hyperbolic equation. Firstly, the existence and uniqueness of approximation solution are proved. Secondly, Based on the known high accuracy results of the about two elements, by use of derivative delivery techniques, the superclose with order O(h2) for both scalar unknown u and the diffusion term v=-Δu in H1-norm and the flux p=-∇u in L2-norm are derived, respectively. Moreover, the global superconvergence is obtained through interpolation post-processing technique. Finally, throught constructing a new asymptotic expansion formula of Q01×Q10 element and a suitable extrapolation scheme, the extrapolation solutions with order O(h3) are derived. Here, h is the subdivision parameter for the space. Reference | Related Articles | Metrics

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Research on totally sequential decision-model of two firms location and pricing based on Hotelling model XU Bing, ZHANG Yang JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2017, 52 (6): 1-9.   DOI: 10.6040/j.issn.1671-9352.0.2017.045 Abstract （1558）      PDF（pc） （1064KB）（1106）       Save It widely exists that firms enter the modern market sequentially. Based on Hotelling model, one decision-model of totally sequential entry with quadratic transportation cost was built to characterize the horizontal competition of two firms in a linear market that the leader makes price-decision after location-decision, and then the follower makes price-decision after location-decision. The analysis of two firms game shows that the follower has the advantage and gains more profits as a late-mover. The leader will locate at the end of market and chooses low-price strategy, while the follower will locate at the center of market and choose high-price strategy. The comparison of the decision-model of totally sequential entry, the game model of two firms making simultaneous decisions of location and price one after another, the game model that two firms simultaneously make location-decisions before they make price-decisions one after another, the game model that two firms make simultaneously price-decisions after their location-decisions were made simultaneously. It shows that the decisions of the first model and the second model are same, in which the prices and profits of two firms are lower than the following models. All four models cant realize the welfare-maximization of society. It needs “the visible hand” of government to regulate the behavior of firms. Reference | Related Articles | Metrics

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A new probabilistic hesitant fuzzy multi-attribute group decision making method based on improved distance measures Mengdi LIU,Xianyong ZHANG,Zhiwen MO JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2024, 59 (3): 118-126.   DOI: 10.6040/j.issn.1671-9352.7.2023.4667 Abstract （77）   HTML （0）    PDF（pc） （2368KB）（102）       Save Aiming at the multi-attribute group decision making problem with known attribute weights under probabilistic hesitant fuzzy environments, hesitation degrees of probabilistic hesitant fuzzy sets are considered, and thus a new method of probabilistic hesitant fuzzy multi-attribute group decision making is proposed based on improved distance measures. Firstly, combining the traditional probabilistic hesitant fuzzy distance measures, improved probabilistic hesitant fuzzy distance measures with hesitation degrees are defined through information fusion, including the Hamming distance, Euclidean distance, and generalized Euclidean distance. These new measures depend on combination coefficients to achieve the theoretical expansion and fusion optimization, and size relationships and parameter monotonicity of distance measures are studied. Secondly, according to the improved distance measures, a new method of multi-attribute group decision making is constructed by using the technique for order preference by similarity to ideal solution(TOPSIS) method, and an example of company location is used to make decision selection. The effectiveness of the proposed method is revealed by parameter analysis and decision comparison. Related researches systematically deepen probabilistic hesitant fuzzy distance measures, and effectively enrich multi-attribute group decision-making methods. Table and Figures | Reference | Related Articles | Metrics

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Extremal eigenvalues of a class of tridiagonal interval matrices JIAN Yuan, LIU Ding-you JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2015, 50 (12): 15-22.   DOI: 10.6040/j.issn.1671-9352.0.2014.549 Abstract （1246）      PDF（pc） （619KB）（1444）       Save A class of tridiagonal interval matrices is studied by the recursive characteristic polynomials and Chebyshev polynomials where some results on eigenvalues are involved. The sharp (lower and upper) bound for the eigenvalues of this class of tridiagonal interval matrices is presended, and the realization matrices whose smallest (largest) eigenvalues reach the lower(upper) bound is characterized. Reference | Related Articles | Metrics

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Identification and statistical analysis methods of personal information disclosure in open government data Haisu CHEN,Jiachun LIAO,Sicheng YAO JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2024, 59 (3): 95-106.   DOI: 10.6040/j.issn.1671-9352.7.2023.2681 Abstract （67）   HTML （1）    PDF（pc） （1846KB）（83）       Save To promote the protection of personal information during data opening, an in-depth analysis of the current status of disclosure of personal information in the open government data is conducted. Firstly, the paper obtains the datasets from relevant platforms and pre-process to classify the datasets that containing personal information based on features such as field and table names, etc. Then, methods of sensitive information identification are applied to identify and extract various types of personal information in the data, and map the information back to individuals to summarise the total number of individuals and detect their associated data. Through data visualizations, the current status of personal information disclosure could be examined. Although some open government data platforms may have implemented certain measures such as data categorization and de-identification, the published open datasets still contain a large amount of personal information, which is required to be improved in terms of data categorization and classification, sensitive information identification and data desensitization in a normative and accurate manner. Table and Figures | Reference | Related Articles | Metrics

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Mean square exponential stability of memristor-based stochastic neural networks with S-type distributed delays WANG Chang-hong, WANG Lin-shan JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2016, 51 (5): 130-135.   DOI: 10.6040/j.issn.1671-9352.0.2015.545 Abstract （1265）      PDF（pc） （1204KB）（833）       Save The mean square exponential stability of a class of memristor-based stochastic neural networks with S-type distributed delays is investigated. A criterion for the stability is given by using Lyapunov functional method and stochastic analysis technique. An example is given to show the feasibility of the theoretical results. Reference | Related Articles | Metrics

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Asymptotics for the LASSO estimator for partially linear models LI Feng1, LU Yi-qiang2 J4    2012, 47 (3): 93-97.   Abstract （1396）      PDF（pc） （908KB）（2667）       Save  Based on the profile least squares method, the LASSO penalty profile least squares estimator is constructed, and the choices of penalty parameter and bandwidth are also discussed. Because the optimization problem is linear, it can be easily implemented. Under some regular conditions, the consistency and asymptotic normality of the estimator for parameter component are investigated. Finally, Monte Carlo simulation studies are conducted to assess the finite sample performance of the proposed variable selection procedures. Related Articles | Metrics

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Research on the angle of repose of natural sand ZHOU Xiang-ling, muhammadtursun·ABUDUREYIM, YU Sheng-qing, LI Hua-zhen JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2015, 50 (07): 89-94.   DOI: 10.6040/j.issn.1671-9352.0.2014.360 Abstract （1618）      PDF（pc） （1652KB）（1585）       Save In this paper we take the sands collected from the natural dunes at the southwest edge of Taklimakan desert as our experimental subjects. We drift the sands into mounds by using static funnel method and record some videos for the drifting processes Then we translate the videos into pictures and analyze them by the computer software “CorelDraw”. By analysis we get the Dependence of the static angle and the collapse angle of the sand mounds on the time and the particle size. Then we make some conclusions: (1) The angle of the sand mound always follow the same circle, i.e., from the maximum static angle to the collapse angle and back to the minimum static angle. Thus the static angles oscillate over time. (2) When the particle diameter is less than 0.3 millimeter, the difference between the collapse angle and the static angle will be increased with the increase of the particle size. Whereas when the particle diameter is greater than 0.3 millimeter, it will be decreased with the increase of the particle size. (3) The average difference between the collapse angle and the static angle is (4.6±0.6)°. (4) The difference between the collapse angle and the static angle of the mixed sand mounds is range(5.2±0.3)°. Reference | Related Articles | Metrics

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Short text clustering based on word embeddings and EMD HUANG Dong, XU Bo, XU Kan, LIN Hong-fei, YANG Zhi-hao JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2017, 52 (7): 66-72.   DOI: 10.6040/j.issn.1671-9352.1.2016.123 Abstract （1625）      PDF（pc） （1207KB）（1745）       Save Short text clustering plays an important role in data mining. The traditional short text clustering model has some problems, such as high dimensionality、sparse data and lack of semantic information. To overcome the shortcomings of short text clustering caused by sparse features、semantic ambiguity、dynamics and other reasons, this paper presents a feature based on the word embeddings representation of text and short text clustering algorithm based on the moving distance of the characteristic words. Initially, the word embeddings that represents semantics of the feature word was gained through training in large-scale corpus with the Continous Skip-gram Model. Furthermore, use the Euclidean distance calculation feature word similarity. Additionally, EMD(Earth Movers Distance)was used to calculate the similarity between the short text. Finally, apply the similarity between the short text to Kmeans clustering algorithm implemented in the short text clustering. The evaluation results on three data sets show that the effect of this method is superior to traditional clustering algorithms. Reference | Related Articles | Metrics