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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
    Abstract1477)   HTML42)    PDF(pc) (2001KB)(349)       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.

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    A survey of visual saliency and salient object detection methods
    Jia XU,Peng JIANG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (3): 28-37.   DOI: 10.6040/j.issn.1671-9352.0.2018.601
    Abstract922)   HTML17)    PDF(pc) (7152KB)(138)       Save

    Saliency detection aims to locate the most attractive areas in image or video data, as the basic task of computer vision field, has receive intensive attentions. Many methods have been proposed recently, these methods usually can be classified into two branches: visual saliency detection and salient object detection. Tough the methods of two branches usually share the similar features and even the frameworks, their performances on datasets of different branch have large gap, seldom works have compared and analyzed them. In this work, we will provide a detailed review and analysis of main works in two branches, including their mechanism, metrics and datasets. Besides, in this work, we summarized approaches to boost visual saliency detection methods for the task of salient object detection. With these approaches, visual saliency detection methods can be applied to detect the salient object and show superior performance that even outperform some specialized state-of-the-art salient object detection methods, thus reduce the performance inconsistence in different specialized datasets.

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    Security domain-based data isolation protection framework for Hive
    Tian-tian CHANG,Xing-shu CHEN,Yong-gang LUO,Xiao LAN
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (3): 1-9.   DOI: 10.6040/j.issn.1671-9352.2.2018.073
    Abstract683)   HTML139)    PDF(pc) (1780KB)(209)       Save

    Aiming at the problem of sensitive information leakage caused by data sharing in Hive database, a data isolation and protection framework (SD-DIPF) based on security domain is proposed, which is combined with data classification and tag-based access control technology. Firstly, the tag level is divided by the hierarchy security tag tree which is used to identify the subject and object in the system. Then, the design idea of security domain (SD) is illustrated with hierarchical tags, the definition of SD and its subdomains and formal proof of security are given. Finally, the platform data is logically partitioned by security domain to ensure the effective isolation of different sensitive levels data. The applicability of SD-DIPF to Hive database is illustrated, and its implementation in Hive database is given based on the existing authentication mechanism. The experimental results show that SD-DIPF can protect sensitive data from being illegally accessed, which proves the feasibility and security of the framework.

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    Trajectory model of area crowd based on WiFi positioning
    Yang XU,Jian-zhong SUN,Lei HUANG,Xiao-yao XIE
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 8-20.   DOI: 10.6040/j.issn.1671-9352.2.2018.200
    Abstract666)   HTML14)    PDF(pc) (8697KB)(195)       Save

    The existing indoor WiFi positioning methods are difficult to resolve the need of crowd trajectory analysis in the large-scale activities and inter-regional. Aiming at this problem, a new crowd location method based on trilateration measurement and signal strength indication (RSSI) for large-scale venues and complex environments is proposed. Crowd positioning in the region, crowd division inside and outside the region, and crowd flow analysis in the region can be achieved. A prediction algorithm based on probability and statistics is used to predict crowd trajectories. A crowd trajectory model in WiFi area is established. A cross regional crowd mobility trajectory model is further established to analyse the flow of crowd in large area inter regional. A proving system of WiFi regional crowd trajectory model is established. Using the data of 2016 Guiyang International Big Data Expo, data visualization analysis is carried out. In this way, the validity of the model is proved.

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    Malicious Office document detection technology based on entropy time series
    An-min ZHOU,Lei HU,Lu-ping LIU,Peng JIA,Liang LIU
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 1-7.   DOI: 10.6040/j.issn.1671-9352.2.2018.072
    Abstract549)   HTML9)    PDF(pc) (5465KB)(131)       Save

    In order to detect malicious Office (*.docx, *.rtf) documents more accurately, a method based on document entropy time sequence to detect malicious Office documents is proposed. This method converts the difference between the malware and the non malicious document binary to the difference between the power spectrum of the time sequence of the file entropy, and then uses three kinds of machine learning methods, IBK, Random Committe (RC) and Random Forest (RF), to learn and detect the data respectively. The experimental results show that the accuracy of the docx format document for XML compression technology can reach 92.14%, while the accuracy of the rich text format (RTF) file can reach 98.20%.

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    Dialogue generation model based on extended keywords information
    Chang-ying HAO,Yan-yan LAN,Hai-nan ZHANG,Jia-feng GUO,Jun XU,Liang PANG,Xue-qi CHENG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 68-76.   DOI: 10.6040/j.issn.1671-9352.1.2018.120
    Abstract545)   HTML11)    PDF(pc) (2482KB)(151)       Save

    Noting that people often reply to others based on the keywords in the post. In order to generate meaningful responses about the keywords, we proposed a dialogue generation model based on an attention mechanism with extended keywords information. First, we extract the keywords of the input, and then form the extended keywords set based on the words which are related to the input keywords using the cosine similarity. The words in the extended keywords set affect the response generation with the attention mechanism. Experiments on the Chinese Weibo dataset and the English Twitter dataset show that our model outperforms the traditional seq2seq model and its variations in both the metric-based evaluation and the human-evaluation.

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    Review spam detection based on the two-level stacking classification model
    Xiang-wen LIAO,Yang XU,Jing-jing WEI,Ding-da YANG,Guo-long CHEN
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 57-67.   DOI: 10.6040/j.issn.1671-9352.1.2018.077
    Abstract516)   HTML7)    PDF(pc) (4106KB)(126)       Save

    For the issue of review spam detection, on the one hand, the time and space complexity of existing methods is high when extracting user behavior relationships and training neural network. On the other hand, the non-standard writing format of E-commercial reviews leads to the indistinct contextual features and most experiment did not consider the effect of the imbalance of data. Therefore, we propose a method for review spam detection based on a two-level stacking classification model. In the method, the relationship between users and products is represented by a triplet. In order to characterize user's behavior and reduce complexity, low-dimensional feature representations are obtained by the principal component analysis. Then, the extracted paragraphs vector representation, information entropy and text similarity is represented as discrete feature to avoid indistinct of contextual features. Finally, the three connections are taken as the overall features combining text and behavioral features. These features are regarded as the input of the two-level stacking classification model in order to improve performance in unbalanced dataset. We conducted experiments in the Yelp 2013 dataset. Experimental results show the F1 value of our proposed method is 1.7%—5.2% better than the state-of-the-art method. What's more, the classification performance is significantly improved in the unbalanced dataset.

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    Key sectors in input-output network
    Jin-qiu GONG,Jin XU,Fa-sheng HU
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 61-67,76.   DOI: 10.6040/j.issn.1671-9352.0.2018.531
    Abstract490)   HTML14)    PDF(pc) (900KB)(93)       Save

    As economic cooperation becomes closer and industrial network becomes more connected, changes in sector production will affect the output of its upstream and downstream sectors, directly or indirectly affecting other sectors, and thereby affecting the overall economy. From the perspective of intersectoral input-output network, the influence of each sector on the aggregate volatility is measured. The input-output network is constructed by direct consumption coefficient matrix to study the role of sectoral shocks in the aggregate volatility. On the basis of the established input-output network, the key sectors are depicted from the perspective of the impact on the aggregate volatility, whose productivity shock has the greatest impact on the output volatility of the entire network. The empirical analysis of China's 2012 input and output data shows that the wholesale and retail, agricultural product sectors have the greatest impact on the aggregate volatility through network linkages, which can be regarded as key sectors.

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    Short-term load forecasting model based on autoencoder and PSOA-CNN
    Wen-qing WANG,Ao-yang HAN,Li-tao YU,Zhi-sheng ZHANG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 50-56.   DOI: 10.6040/j.issn.1671-9352.0.2018.715
    Abstract470)   HTML7)    PDF(pc) (1064KB)(182)       Save

    A short-term load forecasting model which combines the autoencoder and convolutional neural network optimized by particle swarm optimization is proposed. Firstly, the autoencoder is used to process the relevant variable data, reduce the noise variable of the required data, and improve the prediction efficiency. Then particle swarm optimization is used to optimize the weight and threshold of the convolutional neural network., which can effectively improve the prediction accuracy and prediction speed of the prediction model. By simulating the load data of the actual power grid, it is verified that the proposed model has higher prediction accuracy.

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    Plant diversity in nature reserves of Shandong Province
    Xiu-hua ZHANG,Hai-ying QI,Ren-qing WANG,Jian LIU
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 1-10.   DOI: 10.6040/j.issn.1671-9352.0.2019.136
    Abstract468)   HTML15)    PDF(pc) (3185KB)(201)       Save

    The plant diversity of 25 nature reserves above provincial-level with high species diversity in Shandong Province are investigated, and there were 175 families, 918 genera and 2 362 vascular plant species are found, which protected more than 93% vascular plant species in Shandong Province. Qingdao Laoshan provincial nature reserve has the highest plant diversity, followed by Taishan provincial nature reserve and Kunyu mountain national nature reserve among the studied nature reserves by using several biological diversity measurement analysis. A total of 152 rare and endangered plant species were found in the studied nature reserves, and Qingdao Laoshan provincial nature reserve has the most abundant species. According to the existing data, there are 289 alien plant species in the studied area, of which 98 invasive species. We found that all the studied nature reserves have been invaded by alien plant species, and the number of alien herbaceous is far more than alien woody plant. In addition, the reserves with abundant species are invaded by a larger number of alien plant species. The above research can provide scientific basis for plant diversity protection and management of nature reserve in Shandong Province.

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    Research on microblog data collection based on multiple hybrid strategy
    Pei-ming WANG,Xing-shu CHEN,Hai-zhou WANG,Wen-xian WANG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 28-36, 43.   DOI: 10.6040/j.issn.1671-9352.2.2018.058
    Abstract457)   HTML12)    PDF(pc) (1140KB)(193)       Save

    Microblog is becoming the main social media to spread public information, efficient acquisition of microblog data is important to the analysis of online public opinion. Taking Microblog as the research object, there are three data collection strategies through microblog API, simulated login technology and visitor cookie are studied. A data collection method for microblog based on fusion strategy is proposed. An adaptive concurrent data acquisition algorithm is designed and implemented for the web crawler based on simulated login technology. A high available IP proxy pool is designed to accelerate data acquisition for the web crawler based on visitor Cookie. Experimental results show that the fusion strategy is more effective, complete and stable in microblog data collection.

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    vTCM: a virtualized trusted cryptography module based on the virtualization of physical trusted computing environment
    Jun HU,Zi-peng DIAO
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 77-88.   DOI: 10.6040/j.issn.1671-9352.2.2018.211
    Abstract454)   HTML7)    PDF(pc) (1257KB)(192)       Save

    The trust of virtual machine is one of the key issues of virtual machine security. As the source of computer trust, the application of trust cryptography module(TCM) in virtual machine gets more and more attention. A virtual trust cryptography module scheme is presented, which designs a physical vTCM(virtual trusted cryptography module) running environment which can be implemented by expand current TCM(trusted cryptography module) scheme to several switchable vTCM scene, and schedule these vTCM scene to support the TCM access of virtual machines, assign a bound vTCM instance to each virtual machine, and all vTCM instances would run in vTCM scene in turn. The scheme can enhance the trust of vTCM, make management and migration of vTCM more easier. The scheme is implemented in KVM virtualization platform, it shows a good compatibility with existing systems.

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    Itô-Henstock integration of the fuzzy stochastic process
    GONG Zeng-tai, SU Ai
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 1-13.   DOI: 10.6040/j.issn.1671-9352.0.2019.235
    Abstract398)      PDF(pc) (900KB)(366)       Save
    The fuzzy Itô-Henstock integral and the fuzzy Itô-McShane integrals for adapted fuzzy stochastic process with respect to a Brownian motion are defined and their properties are discussed. In addition, the characterization theorems are given and their interrelation of between the fuzzy Itô-Henstock integral and the fuzzy Itô-McShane integral is investigated. The result shows that the fuzzy Itô-Henstock integral is equivalent to the fuzzy Itô-McShane integral when its primitive of fuzzy Itô-Henstock integral is Itô absolutely continuous.
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    Domestic carbon price fluctuation and regional characteristics based on H-P filtering method
    Shao-hui ZOU,Tian ZHANG,Xiao-xia YAN
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 77-87.   DOI: 10.6040/j.issn.1671-9352.0.2018.453
    Abstract391)   HTML14)    PDF(pc) (3494KB)(182)       Save

    The price of carbon emission trading in China has obvious volatility and regional differences. Scientifically describing the volatility of carbon emission trading price and analyzing the differences of different regions are conducive to avoiding investment risks, developing carbon market smoothly and improving the pricing ability of domestic carbon market in the international market. It is also particularly important to speed up the establishment of a unified national carbon market. H-P filtering is a commonly used trend decomposition method for economic variables, which can effectively analyze the seasonal variation law in time series data. Based on monthly data of carbon emission trading prices in seven major regions of China from December 2013 to June 2018, H-P filtering method is used to empirically study the fluctuation law and regional characteristics of domestic carbon prices. The results show that the domestic carbon price has a significant characteristic of "falling in fluctuation", showing 3 complete cycles, the time range of each cycle is 10~22 months. Peak and valley values show a downward trend in varying degrees, and all of them change from positive to negative, the cycle types show a steep downward trend. From the regional perspective, the volatility of carbon emission trading price in Tianjin and Beijing is more obvious, while the fluctuation of carbon emission trading price in Hubei and Chongqing has less impact on Tianjin.

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    Unknown protocol message clustering algorithm based on continuous features
    Zheng-yu LU,Guang-song LI,Ying-zhu SHEN,Bin ZHANG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 37-43.   DOI: 10.6040/j.issn.1671-9352.2.2018.136
    Abstract390)   HTML4)    PDF(pc) (2089KB)(125)       Save

    Clustering of unknown protocol message sequences is the basis for analyzing the protocol format. Based on the traditional K-means algorithm, this paper proposed a continuous-features-based unknown feature message clustering algorithm, which combines the continuity of protocol format field with string matching method. Firstly, coarsely cluster the measured data sets based on the continuity of the protocol format field, extract the initial clustering center of the K-means algorithm, and then iteratively process the data using the message distance and the iterative algorithm with improved convergence function to further cluster the message. Experiments show that compared with the traditional K-means algorithm, the proposed new method improves the accuracy of clustering by 17.58% and reduces the number of iterations by about 58.27%. Compared with EM algorithm and DBSCAN algorithm, the clustering accuracy and time are significantly improved.

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    A deployment strategy for fault recovery of SDN control nodes
    Zhen-peng LIU,Wen-sheng WANG,Yu-peng HE,Jing-wei SUN,Bin ZHANG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 21-27.   DOI: 10.6040/j.issn.1671-9352.2.2018.153
    Abstract384)   HTML6)    PDF(pc) (1115KB)(67)       Save

    Aiming at the situation that the controller has an unrecoverable fault during the operation of the software defined network (SDN) in the WAN, a deployment method considering the fault of the controller node is proposed. Firstly, the network is divided into multiple sub-networks, and then an improved particle swarm optimization algorithm is proposed to deploy the SDN controller in order to achieve higher reliability, lower delay and more balanced load. In the process of network operation, when the controller has an unrecoverable fault, the entropy weight multi-objective decision method is used to determine the target slave controller in the faulty area and upgrade it to the master controller to ensure the normal operation of the network. The experimental results show that compared with the K-means or greedy algorithm, the controller deployment using this method improves the network key indicators such as load balancing rate and link delay of the SDN network, and can reduce decrease the impact of controller failure points on the normal operation of the network at a relatively low costs.

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    Sensitive attribute iterative inference method for social network users
    Xiao-jie XIE,Ying LIANG,Xiang-xiang DONG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (3): 10-17, 27.   DOI: 10.6040/j.issn.1671-9352.2.2018.084
    Abstract378)   HTML9)    PDF(pc) (949KB)(168)       Save

    Analyzing and inferring sensitive information of social network users is conducive to technically quantifying the degree of privacy leakage and protecting privacy. Aiming at the problem that existing user attribute inference methods needs to make strong assumptions on the value of user attributes, an iterative method for user sensitive attributes in social network is proposed by combining the RL iterative classification framework and extending the wvRN relation inference method. Extracting probabilities of user sensitive attributes based on user text and convolution neural network and iteratively updating inference results with neighboring nodes, not only weakens the assumption of user attributes, but also improves the degree of application. The experimental results show that by obtaining a small amount of labeled data in social networks and setting reasonable parameter values for iterative inference methods, better user sensitive attribute inference results can be obtained.

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    The inclusion graph of S-acts
    SUN Shuang, LIU Hong-xing
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 121-126.   DOI: 10.6040/j.issn.1671-9352.0.2018.504
    Abstract375)      PDF(pc) (430KB)(145)       Save
    Let S be a semigroup and M be an S-act. The inclusion graph of M, denoted by G(M), is the undirected simple graph whose vertices are all non-trivial subact of M and defining two distinct vertices I and J to be adjacent if and only if I⊆J or J⊆I. Some results on completeness, connectivity, diameter, girth, the clique number and the chromatic number of G(M) are presented.
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    Counting solutions of a binary quadratic congruence equation
    DUAN Ran
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 108-120.   DOI: 10.6040/j.issn.1671-9352.0.2018.407
    Abstract369)      PDF(pc) (443KB)(121)       Save
    Let n be a positive integer. Denote by Zn the ring of residue classes mod n, and by Z*n the group of units in Zn, i.e. Z*n={s:1≤s≤n and gcd(s,n)=1}. The main purpose of this paper is using congruence conclusion and some results of exponential sums to study the number of elements of the set T(a,b,c,n)={(x,y)∈(Z*n)2:ax2+by2+c≡0 mod n} and give an exact computational formula for the number of elements of T(a,b,c,n).
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    Supply chain coordination strategy of joint contract under the disruption increased demand
    Xin-hua HE,Cai-yun YOU,Wen-fa HU
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 68-76.   DOI: 10.6040/j.issn.1671-9352.0.2018.295
    Abstract360)   HTML3)    PDF(pc) (1043KB)(89)       Save

    Considering the impact of disruption increased demand on the revenue of emergency service supply chain, and using joint contracts to coordinate emergency logistics service supply chain. Firstly, the coordination of the joint contract under the premise of stable market demand is analyzed. It is pointed out that the service supply chain under the joint contract is more coordinated. Then optimizing the profits of logistics service supply chain under emergencies through reasonable contract parameters, the joint contract can continue to coordinate the supply chain in response to emergencies, and get the optimal ordering strategy of the integrator. Finally, through the analysis of the example, the validity of the joint contract coordination emergency is further verified, and more accurate information is provided for the accurate decision of the supply chain.

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    Study on coupling relationship between urban land use and ecological environment in cities of the Yellow River Delta
    Hao CHEN,Ren-qing WANG,Jian LIU
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 11-20.   DOI: 10.6040/j.issn.1671-9352.0.2018.755
    Abstract359)   HTML5)    PDF(pc) (686KB)(124)       Save

    In order to explore the coupling relationship between urban land use and ecological environment, and promote the harmonious development of land use and ecological environment, the core cities of the Yellow River Delta, Dongying and Binzhou, were selected as the study areas. The coupling coordination measure model was used to analyze the land use comprehensive index, the ecological environment comprehensive index and the coupling coordination degree of the two systems from 2002 to 2016. Meanwhile, sensitivity verification was carried out on the weights of indicators. The results showed that the comprehensive index of land use and ecological environment in Dongying and Binzhou had an upward trend from 2002 to 2016, from the perspective of coupling degree and coupling coordination degree, the research areas were in a good coupling stage, and the coordinated development of land use and ecological environment experienced five stages from moderate imbalanced to well coordinated. The weights of indicators determined by the entropy method was reasonable and reliable. The study not only provide the scientific basis for the management of the two cities, but also provide study the method and reference for other similar cities.

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    A lightweight anti-desynchronization RFID mutual authentication protocol
    Xin-min DAI,Xiao-yao XIE
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 52-76.   DOI: 10.6040/j.issn.1671-9352.2.2018.079
    Abstract356)   HTML4)    PDF(pc) (698KB)(76)       Save

    Lightweight radio frequency identification (RFID) protocols usually adopt a synchronous update mechanism to avoid leakage of location privacy, but it brings the problem of desynchronization attack. Desynchronization attack can cause inconsistent updates of the secret data between the tag and the database. As a result, the tag does not work properly. After the analysis of an existing protocol, it is found that it is vulnerable to the attack of desynchronization. In view of the defects of the existing protocol, a new lightweight mutual authentication protocol against desynchronization attack is proposed. The formal analysis of the new protocol is carried out by using the ideal honest theory of the strand space, which proves the correctness of the new protocol.

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    Study on vegetation composition and flora of river wetlands in Shandong Province
    Yu LIANG,Xiao-li FAN,Liang MA,Qiang WANG,Yong FANG,Wei-dong WANG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 21-25.   DOI: 10.6040/j.issn.1671-9352.0.2019.137
    Abstract353)   HTML5)    PDF(pc) (1227KB)(92)       Save

    Wetlands are one of the most important terrestrial carbon pools in the world, they are also sensitive to global change. Based on the investigation data, we analysesed the vegetation composition, plant growth pattern and floristic geographical composition of river wetlands in Shandong Province, and expounede the relationship between them and plants. The rivers wetland area in Shandong Province is 257 795.20 hm2, accounting for 14.84% of the whole province wetland area.There are 301 species of plants belonging to 216 genera and 82 families in the rivers wetlands of Shandong Province. There are 15 distribution types and 12 variants in floristic geography. There are 145 genera distributed indistribution types and variants of temperate and tropical characteristics, accounting for 67.13% of the total genera, reflecting the temperate and tropical characteristics of plant genera distribution.

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    Strong hyper deductive systems in hyper equality algebras
    CHENG Xiao-yun, XIN Xiao-long
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 14-19.   DOI: 10.6040/j.issn.1671-9352.0.2018.587
    Abstract352)      PDF(pc) (337KB)(163)       Save
    Some types of strong hyper deductive systems in hyper equality algebras are introduced and investigated. Some representations of generated strong hyper deductive systems are given. Then, Two types of important strong hyper deductive systems, namely, implicative and positive implicative strong hyper deductive systems are studied. In particular, characterizations of them are given and the relations between them are discussed.
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    Non-uniform dependence on initial data for the periodic two-coupled Camassa-Holm system
    WANG Hai-quan
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 42-49.   DOI: 10.6040/j.issn.1671-9352.0.2019.125
    Abstract352)      PDF(pc) (388KB)(77)       Save
    Considered herein is the initial value problem for the periodic two-coupled Camassa-Holm system. It is shown that the solution map of this problem is not uniformly continuous in Besov spaces B3/22,1(T)×B3/22,1(T). Based on the well-posedness result and the lifespan for this problem, the method of approximate solutions is utilized. The same approach can be used to discuss this property of the solutions for the other nonlinear partial differential equations.
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    Information measures of interval valued Pythagorean fuzzy sets and their applications
    SUN Qian-qian, LI Xiao-nan
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (9): 43-53.   DOI: 10.6040/j.issn.1671-9352.0.2019.038
    Abstract350)      PDF(pc) (507KB)(119)       Save
    Entropy, distance and similarity are important information measurement tools in fuzzy sets and their generalization theories. The information metrics research based on interval valued Pythagorean fuzzy sets mostly involves the distance formula of interval valued Pythagorean fuzzy numbers, and rarely involves metrics of ambiguity and similarity. In view of this situation, firstly, the axiomatization definition of entropy, distance and similarity of interval valued Pythagorean fuzzy sets is first proposed. Then study the relationship between entropy, distance and similarity. Finally, the entropy and similarity of the interval valued Pythagorean fuzzy set are applied to the field of pattern recognition. Comparative analysis shows the flexibility and effectiveness of the proposed measures.
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    An anonymous and provably remote user authentication protocol using extended chaotic maps for multi-server system
    Juan QU,Yu-ming FENG,Yan-ping LI,Li LI
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (5): 44-51.   DOI: 10.6040/j.issn.1671-9352.2.2018.207
    Abstract348)   HTML4)    PDF(pc) (456KB)(111)       Save

    The existing remote user authentication schemes for multi-server environment are not resilient to defend against various security attacks and does not provide user anonymity. Therefore, a remote user authentication scheme for multi-server environment based on biometric and chaotic maps is proposed to realize authentication between the user and multi-server. The user and multi-server can authenticate each other and share a session key for subsequent secure communication. The proposed scheme is proved to be secure using the BAN logic. Additionally, analysis results show that the proposed protocol can resist masquerade attack, offline password guessing attack, stolen smart card attack, etc. Finally, comparing the scheme with other relevant schemes and the comparative results show that our scheme is efficient in terms of computation cost, communication cost, it can be more suitable for practical application.

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    Hidden attractor with two memristors and Hamilton energy control
    MU Na-na, AN Xin-lei, XU Hao-nan
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (9): 91-97.   DOI: 10.6040/j.issn.1671-9352.0.2018.708
    Abstract341)      PDF(pc) (5395KB)(201)       Save
    Based on the Kirchhoffs law, a nonlinear chaotic circuit model is designed by including a flux-controlled memristor and a charge-controlled memristor. The hidden attractor is found through analyzing characteristics of the equilibrium points. And then, simulation and comparison studies of bifurcation diagram and phase trajectory and Poincaré map of parameter are carried out by simulation software. The Hamiltonian energy function of the memristor system is calculated according to Helmholtz theorem, and the relationships between the current and the energy are discussed. Based on this, the new Hamilton energy control method is proposed to control the memristor system to the desired states by choosing different control parameter.
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    Fuzzing sample optimization method for software vulnerability detection
    Jing ZHANG,Cheng CHEN,Huan-ke ZHENG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (9): 1-8, 35.   DOI: 10.6040/j.issn.1671-9352.0.2019.205
    Abstract337)   HTML6)    PDF(pc) (681KB)(161)       Save

    Software vulnerability detection Fuzzy testing techniques are commonly used in information physical fusion systems.But there are a large number of redundant test samples in Fuzzing technology, and the sample detection anomaly is less effective. Therefore, this paper proposes a Fuzzing sample optimization method for software vulnerability detection. Firstly, the samples that are not accepted by the software in the random sample are filtered out, and the improved dynamic programming algorithm is used to calculate the sample reduced set, and the number of initial samples is reduced. Then track the stain propagation path during the test, use the improved algorithm of Simhash and Hamming distance to solve the similarity of the sample propagation path, and further reduce the sample redundancy by deleting the samples with higher similarity. Finally, the genetic variation of the sample that triggers the abnormality is constructed. New test samples will increase the validity of the sample. It can be seen from the experimental results that compared with the method based on greedy algorithm and based on abnormal distribution orientation, the proposed method effectively reduces the test sample redundancy and improves the validity of the test sample.

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    Social network user identity linkage model based on comprehensive information
    YANG Ya-ru, WANG Yong-qing, ZHANG Zhi-bin, LIU Yue, CHENG Xue-qi
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (9): 105-113.   DOI: 10.6040/j.issn.1671-9352.1.2018.115
    Abstract331)      PDF(pc) (3693KB)(75)       Save
    With the increasing popularity of social media sites, users prefer to join multiple online social networks, how to associate multiple user identities in a social network as a new job in social media is of great significance. This paper studies a representative user identity linkage model and proposes a user identity linkage model based on comprehensive information(BiALP). The model learns the internal structure information, attribute information and content information of the network through the node expression method. It is characterized by the node representation of the source network and the target network, and is based on the associated user pairs. With tagged data, the relationship between the source network and the target network is learned through a binary supervised learning manner. A large number of experiments have shown that the BiALP model has a significant improvement(35%)compared to other representative user identity linkage models.
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    Positive periodic solutions for second-order singular differential equations with damping terms
    CHEN Rui-peng, LI Xiao-ya
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 33-41.   DOI: 10.6040/j.issn.1671-9352.0.2018.707
    Abstract327)      PDF(pc) (412KB)(84)       Save
    This paper studies the existence of positive periodic solutions of u″+p(t)u'+q(t)u=f(t,u)+c(t), where p,q,c∈L1(R/TZ;R), f is a Carathéodory function and is singular when u=0. By means of the fixed point theory, several existence theorems are established for the above equation, and some recent results in the literature are generalized and improved.
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    Analysis of a stochastic single population system with age-dependent and diffusion in a polluted environment
    HU Yong-liang, LUO Zhi-xue, LIANG Li-yu, FENG Yu-xing
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (9): 62-68.   DOI: 10.6040/j.issn.1671-9352.0.2019.124
    Abstract327)      PDF(pc) (419KB)(127)       Save
    A new stochastic single population system with age-dependent and diffusion in a polluted environment is formulated and investigated. The existence and uniqueness of the solution of this stochastic system is obtained via It(^overo)s formula in Hilbert space. The general stochastic biological population model with age structure and diffusion is extended by adding toxicant to the population.
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    Comparison of concentrations and chemical compositions of PM10 during hazy and non-hazy days in Beijing and Islamabad
    Xian-chu WU,Bin CHEN,Tian-xue WEN,Imran SHAHID,Ammara HABIB,Guang-yu SHI
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (7): 42-49, 56.   DOI: 10.6040/j.issn.1671-9352.0.2019.039
    Abstract319)   HTML3)    PDF(pc) (1755KB)(121)       Save

    In order to study the characteristics of heavy metals, water-soluble inorganic ions and carbon components in winter PM10 in Beijing and Islamabad, PM10 samples were collected at urban site in Beijing and Islamabad from December 2014-January 2015. The concentrations of above three compositions of PM10were analyzed. The results indicated that the concentrations of heavy metals were at high levels during sampling period in both two sites. The concentrations of As、Cr(Ⅵ) in Beijing and Cd、Cr(Ⅵ) in Islamabad were both exceeded the WHO guideline. Heavy metals were enhanced during haze days. The main sources of heavy metals were coal burning and automobile in Beijing, while in Islamabad was mainly automobile according to PCA. Secondary pollution of water-soluble inorganic ions in atmosphere in both sites was heavy. The concentrations of water-soluble inorganic ions also enhanced due to automobile. Correlation between OC and EC was strong(especially in non-haze days) in Beijing but it was low in Islamabad. They implied that OC and EC tended to be mainly from the same primary sources and were controlled by similar processes after being emitted in Beijing, mainly due to coal burning and automobile; but the source of carbonaceous species was relatively complex in Islamabad. The concentration of SOC in sampling period in Beijing was 2.58 μg/m3, accounting for only 10.1% of the OC mass concentration; while there was basically no SOC in Islamabad.

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    Topic tag popularity prediction based on multi-dimensional features
    Xin-le WANG,Wen-feng YANG,Hua-ming LIAO,Yong-qing WANG,Yue LIU,Xiao-ming YU,Xue-qi CHENG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2020, 55 (1): 94-101.   DOI: 10.6040/j.issn.1671-9352.1.2018.136
    Abstract317)   HTML6)    PDF(pc) (958KB)(189)       Save

    The characteristics of user network structure information and topic tags such as sentiment and regionality are analyzed. A popularity prediction model that considers the user's fan network structure characteristics and the subject tag's own characteristics is proposed. Experiments have proved that the newly proposed feature is effective and has a high reference value for predicting the popularity of future topic tags.

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    Research of an epidemic model on adaptive networks
    CHEN Lu, ZHANG Xiao-guang
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (9): 76-82.   DOI: 10.6040/j.issn.1671-9352.0.2018.729
    Abstract315)      PDF(pc) (448KB)(99)       Save
    By using the triple approximation formula under multinomial distributions, the SIS moment closure infectious disease model in the adaptive network is closed, the effects of adaptive behavior on the spread of infectious diseases under multinomial distributions is studied. Through the theory of qualitative and stability, the basic reproduction number R0 of the model is obtained and the stability of the equilibrium points are analyzed. Adaptive behavior of rewiring has multiple effects on infectious disease transmission are obtained: When the relative infection rate is small enough, the model has a standard forward bifurcation and when R0<1, the disease tends to be extinct; on the contrary, mathematically, it is rigorously proved that the rewiring can lead to the occurrence of complex dynamic behaviors such as the backward bifurcation and saddle-node bifurcation, ect. Therefore R0<1 is not enough to control the spread of infectious diseases.
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    Cyclic controlled quantum teleportation by using a ten-qubit entangled state as the channel
    PENG Jia-yin
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (9): 98-104.   DOI: 10.6040/j.issn.1671-9352.0.2019.093
    Abstract308)      PDF(pc) (509KB)(122)       Save
    The paper proposes a protocol of cyclic controlled teleportation for three unknown two-qubit states by using a ten-qubit maximally entangled state as the quantum channel. In this protocol, Alice can teleport her two-qubit state of qubits a and a' to Bob, Bob can transfer his two-qubit state of qubits b and b' to Charlie, and Charlie can also transmit his two-qubit state of qubits c and c' to Alice. It is shown that only if the senders Alice, Bob, Charlie and the controller David collaborate with each other, the cyclic controlled quantum teleportation can be realized successfully.
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    Pricing strategy of vehicles and cargos matching platform in the sharing economy
    Yun-miao GUI,Zhong WU,Hong-chun HU
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2020, 55 (1): 69-76,85.   DOI: 10.6040/j.issn.1671-9352.0.2019.001
    Abstract304)   HTML18)    PDF(pc) (1701KB)(247)       Save

    In order to improve the competitive advantage and performance of the vehicles and cargos matching platform, the article analyzes the characteristic of service providers of vehicles and cargos matching platform. By dividing it into professional and non-professional service providers, a game model of the vehicles and cargos matching platform is constructed. The result show that, if platforms' two sides are single-homing, the vehicles and cargos matching platform would charges the same fee for two kinds of suppliers, but if platforms' one side is multi-homing, the vehicles and cargos matching platform tend to charge high access price for non-specialist suppliers and lower access price for professional suppliers. Moreover, a strategy of accessing to suppliers firstly would be more beneficial to the oligopoly vehicles and cargos matching platform.

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    Existence of ground states for linear coupled systems of lower critical Choquard type
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 62-67.   DOI: 10.6040/j.issn.1671-9352.0.2018.670
    Abstract301)      PDF(pc) (339KB)(112)       Save
    To the best of our knowledge, there is few result about linearly coupled systems of Choquard type with the lower critical up to now. The existence of ground state solutions for a class of Choquard-type linear coupled systems with lower critical exponents is studied by variational methods. It is a promotion and supplement to the previous research results.
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    Security analysis model of behavior based on cryptographic protocols implement at source code level
    Fu-sheng WU,Huan-guo ZHANG,Ming-tao NI,Jun WANG
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (3): 18-27.   DOI: 10.6040/j.issn.1671-9352.2.2018.053
    Abstract301)   HTML4)    PDF(pc) (692KB)(105)       Save

    An analytical model of the behavior based on the cryptographic protocols implement at source code level is proposed. The cryptographic protocol implementations can be divided into two parts by the model that is proposed. One is an external behavior (the behavior of opening the interactive communications in cyberspace); the other is an internal behavior (the behavior of cryptographic protocol implements at the source code level). Though the behavior controllability, it is possible to find, control, or correct the security of the cryptographic protocol implementations at the source code level. Based on the analysis model method, a simulation experiment using classic cryptographic protocol as an example was given. The results show that the behavioral security of the cryptographic protocol implementations is controllable.

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    Inverse spectral results for AKNS systems with partial information on the potentials
    JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE)    2019, 54 (8): 50-54.   DOI: 10.6040/j.issn.1671-9352.0.2018.334
    Abstract300)      PDF(pc) (315KB)(93)       Save
    We consider the AKNS systems on the interval[0,1] and prove that two potentials already known on [a,1](a∈(0,1/2])and their difference in Lp are equal if the number of their common eigenvalues is sufficiently large. The result here is to write down explicitly this number in terms of p(and a)showing the role of p.
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