2017 Vol.35

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Journal of Applied Sciences    2017, 35 (1): 0-0.   Abstract （440）      PDF（pc） （419KB）（275）       Knowledge map    Save Related Articles | Metrics | Comments（0）

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Journal of Applied Sciences    2017, 35 (1): 0-0.   Abstract （103）      PDF（pc） （29KB）（186）       Knowledge map    Save Related Articles | Metrics | Comments（0）

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Privacy-Preserving Distributed Naive Bayes Data Mining YE Yun, SHI Cong-cong, YU Yong, HUAI Meng-di, LIN Wei-min, GAO Peng Journal of Applied Sciences    2017, 35 (1): 1-10.   DOI: 10.3969/j.issn.0255-8297.2017.01.001 Abstract （728）      PDF（pc） （2745KB）（404）       Knowledge map    Save Current works involving distributed privacy-preserving Naive Bayes data mining only consider the privacy of each party but ignore the fact that the learned Naive Bayes classifer can also potentially disclose the global privacy.Additionally, these works cannot deal with collusion attacks.Based on secure multi-party computation and differential privacy, we propose a horizontally distributed privacy-preserving Naive Bayes protocol.In this protocol, we construct the privacy-preserving Naive Bayes protocol based on the secure multiparty computation theories to protect each party's privacy.We then make the learned Naive Bayes achieve differential privacy to prevent the global privacy from the learned classifer.To resolve two kinds of collusion attacks, we construct a random selection algorithm based on the secret sharing theories.To achieve this, we randomize the Laplace noise provider.In this way, collusions among massive parties and adjacent parties are prevented.Using these steps, we construct a privacy-preserving Naive Bayes algorithm.Experimental results reveal that the proposed distributed protocol has good classifcation performance regardless of the number of participating parties.In other words, it has high scalability. Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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Antenna Directionality of Micropower Wireless Communication Module in Smart Meter YU Hua-dong, OU Qing-hai, ZHANG Zhe, WANG Yun-di, WU Qing, ZHAO Hong-hao, LU Yi Journal of Applied Sciences    2017, 35 (1): 11-20.   DOI: 10.3969/j.issn.0255-8297.2017.01.002 Abstract （1485）      PDF（pc） （8708KB）（583）       Knowledge map    Save Received wireless power can be increased under the same conditions by reasonable installation angle of directional antennas.A 230 MHz normal mode helix antenna of micropower wireless communication module in a smart meter is designed and implemented.Directivity of the antenna is discussed.The installation angle of antenna is improved based on actual installation mode of antenna and the smart meter.Simulation and measurements show that the average received wireless power in a micropower wireless communication module increases by 2.4 dBm as compared to that without installation angle improvement.In the same environment and the same signal encoding modulation mode, signal-to-noise ratio of the received signal is increased, and therefore quality of wireless communication between a smart meter and a concentrator can be improved. Reference | Related Articles | Metrics | Comments（0）

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Improved Estimation of Distribution Algorithm (EDA) for Locating Fault Sections in Distribution Networks WANG Si-ming, TONG An-rong Journal of Applied Sciences    2017, 35 (1): 21-30.   DOI: 10.3969/j.issn.0255-8297.2017.01.003 Abstract （773）      PDF（pc） （1972KB）（411）       Knowledge map    Save In locating fault sections on the feeder of a distribution network, artifcial intelligence algorithms have shortcomings such as large initial population, too many iterations and premature convergence.Thus, an algorithm for distribution estimation based on bacterial foraging (BF-EDA) is proposed.To enhance local optimization capability and avoid premature estimation of distribution algorithm (EDA), bacterial foraging behavior is introduced into the EDA.Experimental results show that the BF-EDA can effectively locate faults in a multiple source ring-open distribution network with good accuracy, rapidity and fault tolerance. Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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Spatiotemporal Distribution of Lightning Disasters of Power Lines in Hubei Province Using Data Mining Based on Apriori Association Rules HUANG Jun-jie, TAN Bo, CHEN Xiao-ming, CHEN Jiang-ping, RUAN Ling, FENG Wan-shu, XIONG Yu Journal of Applied Sciences    2017, 35 (1): 31-41.   DOI: 10.3969/j.issn.0255-8297.2017.01.004 Abstract （1024）      PDF（pc） （14516KB）（316）       Knowledge map    Save By using the data of lightning failure and monitoring of the past years provided by Hubei Grid, this paper studies the characteristics of daily and monthly distributions of lightning activity, as well as the elevation distribution and spatiotemporal distribution.The results show that lightning in Hubei Province mainly occurs in July and August, and between 15:00 and 18:00 during the day.The active regions include the east parts of Huangshi and Xianning, central Wuhan, central and eastern Yichang, and southern and part of northern Xiangfan.The multi-source lightning data are fused with an algorithm based on Apriori association rules.The research shows that lightning shield of the power lines may fail when daily average relative humidity is higher than 80%, daily average air pressure is higher than 1×105Pa, or daily average water vapor pressure is between 3×103 Pa and 4×103 Pa.In these cases, therefore, measures should be taken to strengthen lightning prevention.Analyzing big data of lightning around power lines using the association rules can provide guidance to decision makers of power lines for disaster prevention. Reference | Related Articles | Metrics | Comments（0）

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Data Mining for Correlation Rules of Lightning in Hubei Province CHEN Jiang-ping, TAN Bo, LIAN Shi-zhong Journal of Applied Sciences    2017, 35 (1): 42-50.   DOI: 10.3969/j.issn.0255-8297.2017.01.005 Abstract （752）      PDF（pc） （9151KB）（296）       Knowledge map    Save Based on the historical data of each July between 2012 and 2014 provided by the lightning location system of Hubei province, this paper reveals possible relationship between lightning and various environmental factors concerning meteorological conditions and terrains.Combined with the algorithm of density-based spatial clustering of applications with noise (DBSCAN) and the kernel density algorithm, insignifcant locations with rare lightning are eliminated.Qualitative and quantitative relations between lightning locations in Hubei with different peak currents and various factors such as terrains and meteorological factors are obtained using the a priori data mining algorithm for correlation rules.In Hubei, which is mainly a low-lying land, lightning strikes with low current of 10~75 kA are likely to occur in forests or farmlands.In these areas, lightning is strongly correlated with average values of air pressure, relative humidity, vapor pressure, precipitation, temperature and wind speed.Lightning with high current of more than 100 kA has a certain relation with wind speed, daily vapor pressure, daily average temperature and minimum temperature.Lightning with very high current of 157.9~250.7 kA is correlated with precipitation. Reference | Related Articles | Metrics | Comments（0）

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Localization of Double Layer Location System Based on IBeacon Network YAO Wei-qiang, ZHANG Jin-yi, BAO Shen, LIANG Bin Journal of Applied Sciences    2017, 35 (1): 51-62.   DOI: 10.3969/j.issn.0255-8297.2017.01.006 Abstract （959）      PDF（pc） （11606KB）（504）       Knowledge map    Save In many traditional indoor large space localization method, it is difcult to improve both positioning accuracy and real-time performance.This paper proposes a localization system based on iBeacon network.The system composes of two optimized indoor positioning algorithms, and has an iBeacon dual layer positioning architecture.The former achieves rapid location with an algorithm that matchesa region of space probability, and achieves high precision within each region in the area with a weighted centroid algorithm.The latter, based on the iBeacon identifcation code, is divided into two levels of node localization.Different levels of positioning is achieved by using different combinations of these nodes.In the positioning process, the system uses the iBeacon double layer positioning architecture at different levels of the two positioning algorithms to improve accuracy of real-time positioning.Experimental results show that, with similar accuracy, the proposed system improves the real-time performance by 55.29% and 54.18% respectively compared with K-nearest neighbor (KNN) and weighted K-nearest neighbor (WKNN).Positioning accuracy is improved by 37.35% compared with an improved weighted centroid algorithm based on RSSI.The proposed system has high economic and social values as it can be used for navigation in large buildings and detect pedestrian paths. Reference | Related Articles | Metrics | Comments（0）

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Connectivity Modeling for Vehicular Communication Networks CHEN Si-min, ZHAO Hai-tao, ZHU Hong-bo, ZHANG hui Journal of Applied Sciences    2017, 35 (1): 63-70.   DOI: 10.3969/j.issn.0255-8297.2017.01.007 Abstract （701）      PDF（pc） （4800KB）（489）       Knowledge map    Save Vehicular communication network is a high-speed mobile Ad-Hoc network (MANET).Vehicle connectivity is important in studying multi-hop communications, and is a challenge due to rapid changes of topology caused by fast moving of vehicles and frequent disconnection of the network.In this paper, a connectivity model of vehicular communication network based on headway is established based on the point of headway.It is done by reasonably analyzing the trafc, and assuming that the headway follows the Erlang distribution and the speed of vehicles follows normal distribution.The relation between the numbers of arriving vehicles per unit time period and the average vehicle density, that between the range of communication and vehicle connectivity are analyzed.Simulation results show that the more vehicles arrive in a unit time period, the higher the average vehicle density.Consequently, an optimum range of communication can be obtained for good connectivity.The proposed network connectivity model is useful for transmitting data in vehicular communication networks. Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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Modeling and Generation of Non-stationary Rice Fading Channel with Time Evolution LIU Xing-lin, ZHU Qiu-ming, CHEN Ying-bing, CHEN Xiao-min, LI Hao Journal of Applied Sciences    2017, 35 (1): 71-80.   DOI: 10.3969/j.issn.0255-8297.2017.01.008 Abstract （736）      PDF（pc） （10007KB）（274）       Knowledge map    Save When the transmitter or receiver moves fast, wireless radio channel for mobile communication system is non-stationary.This paper establishes a non-stationary Rice fading channel model with time evolution for the dynamic propagation link between mobile and base stations.A generation method is proposed for non-stationary fading channels based on the sum-of-linear-frequency-modulation (SoLFM) signals, and an algorithm for parameter updating designed.Experimental results show that the proposed method can ensure smooth handoff of fading channel states and continuity of fading amplitude and phase.It can also reproduce non-stationarity of a fading channel, and ensure the channel model's time-variant envelope distribution and time-variant Doppler power spectrum agree with the desired values.The model and its generation method can be applied to evaluate performance and validate a wireless mobile system in a time-variant propagation environment. Reference | Related Articles | Metrics | Comments（0）

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Gesture Tracking Using Improved Linear Extrapolation Predictor YAO Heng, YUAN Min, QIN Chuan, TIAN Ying Journal of Applied Sciences    2017, 35 (1): 81-89.   DOI: 10.3969/j.issn.0255-8297.2017.01.009 Abstract （805）      PDF（pc） （8967KB）（330）       Knowledge map    Save To improve accuracy of gesture tracking in dynamic gesture recognition system, a gesture tracking algorithm using an improved linear extrapolation predictor is proposed.Specifcally, to improve prediction accuracy, the algorithm uses the average displacement of two previous frames as the future-frame predictor.Besides, to deal with occlusion and hands-overlap, the target movement direction is determined based on the slope of ftting line with fve points.Thus deviation between the predicted and actual positions caused by the changing gesture centroid is reduced.Experimental results show that efciency of the proposed gesture tracking method with the average prediction deviation is reduced to 3.374 pixels.In addition, even in the case of occlusion and hands-overlap, the gesture target can also be tracked effectively. Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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Signal-to-Noise Ratio in Low Light Images from Microsatellite ZHANG Yang, ZHONG Xing Journal of Applied Sciences    2017, 35 (1): 90-98.   DOI: 10.3969/j.issn.0255-8297.2017.01.010 Abstract （897）      PDF（pc） （2055KB）（467）       Knowledge map    Save To acquire low-light remote sensing images, remote sensing platform and sensors are studied.By increasing integration time, low-light remote images are combined.In contrast to the current imaging models we have on satellite, a staring imaging model can achieve longer integer time.The new microsatellite platform can collect low-light remote image in this model.A mathematical model for signal-to-noise ratio is established to obtain functional relationship among relative optical aperture, integration time and signal-to-noise ratio.An experimental platform is setup to collect target images acquired in a low light environment with different integration time for analysis of signal-to-noise ratio. Reference | Related Articles | Metrics | Comments（0）

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Multi-task Automatic Prostate Segmentation with Group CT Planning Images DAI Xiu-bin, Deng Huang-jian, LIU Dai-fu, LIU Ke, ZHOU Qing-rong Journal of Applied Sciences    2017, 35 (1): 99-106.   DOI: 10.3969/j.issn.0255-8297.2017.01.011 Abstract （889）      PDF（pc） （13066KB）（248）       Knowledge map    Save To automatically and accurately segment prostates in CT planning images, a multi-task CT prostate segmentation method is proposed based on group images.The group images with those from other patients are frst mapped to various spaces of reference images to form a multiple training task.The random forest method and the automatic context model are used to train a series of classifers.The trained classifers are then iteratively applied to CT images to be segmented.Multiple classifcation probability maps are thus produced.The fnal segmentation result is obtained using a majority voting method.Experimental results show that, compared with single-task segmentation, proposed multi-task segmentation based on group images can effectively improve accuracy of prostate segmentation for CT planning images. Reference | Related Articles | Metrics | Comments（0）

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3D Measurement of Regular Components Base on Structured Light with an Intersecting-Parallels Shape CAI Chen, PAN Bin, LIU Zhen-ning Journal of Applied Sciences    2017, 35 (1): 107-116.   DOI: 10.3969/j.issn.0255-8297.2017.01.012 Abstract （932）      PDF（pc） （10146KB）（529）       Knowledge map    Save This paper proposes a method using structured light with an intersectingparallels shape to carry out three-dimensional (3D) vision measurement for regular components.This structured light is projected onto a calibration plate.Images are acquired and processed to calibrate the measurement system.The light is then projected on the component and images are captured and processed in order to extract the centers of the light strips.Combined with the calibration and light strip data, 3D coordinates of the object are calculated precisely.Experimental results show that the measure mentrange is between 700 mm and 1 000 mm, with errors less than 0.5 mm. Reference | Related Articles | Metrics | Comments（0）

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Handover Management Based on MPTCP in SDN Environment SUN Mao-xin, QIAN Hong-yan, CHEN Bing, ZHANG Xuan Journal of Applied Sciences    2017, 35 (1): 117-127.   DOI: 10.3969/j.issn.0255-8297.2017.01.013 Abstract （933）      PDF（pc） （6814KB）（1210）       Knowledge map    Save To improve handover performance of wireless network, we use the software defned networking (SDN) architecture and propose a handover method based on the multipath transmission control protocol (MPTCP).Handover decision is made according to the proposed multiple attributes handover algorithm based on fuzzy logic.The algorithm uses the current received signal strength (RSS), forecasting RSS and available bandwidth for parameters in designing a fuzzy logic controller, and calculates parameters of membership values.Values of network performance is then calculated to make handover decision.To implement the handover manangement, we use MPTCP in the transport layer of both sides of communication.This protocol allows establishment of multiple data transmission path.Mobile equipment can use MPTCP to connect multiple access point (AP) simultaneously.When a link switching occurs, the rest of the links continue to maintain communication.To show performance of the handover mananament, we have built a OpenFlow test bed.The experimental results show that the proposed mechanism can achieve seamless handover and ensure quality of service (QoS). Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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Dynamic Path Planning of Unmanned Aerial Vehicle Based on Sparse A*Algorithm and Cultural Algorithm LI Jun-hua, LIU Qun-fang Journal of Applied Sciences    2017, 35 (1): 128-138.   DOI: 10.3969/j.issn.0255-8297.2017.01.014 Abstract （1303）      PDF（pc） （15362KB）（361）       Knowledge map    Save For dynamic path planning of unmanned aerial vehicle (UAV), we combine digital terrain, weather information, and other data to establish a full digital probability map.We then use a two level hierarchical planning method that includes ofine static planning and online real-time dynamic planning to realize dynamic path planning of UAV.The method is based on the sparse A* algorithm and cultural algorithm (CA).It solves the winding problem of sparse A* algorithm and improves reliability and real-time performance of tracking. Reference | Related Articles | Metrics | Comments（0）

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Journal of Applied Sciences    2017, 35 (2): 0-0.   Abstract （338）      PDF（pc） （406KB）（227）       Knowledge map    Save Related Articles | Metrics | Comments（0）

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Journal of Applied Sciences    2017, 35 (2): 0-0.   Abstract （125）      PDF（pc） （28KB）（167）       Knowledge map    Save Related Articles | Metrics | Comments（0）

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Systematic Polar Coded Cooperation Based on Puncturing LI Kun, WU Shao-hua, GAO Xiang, ZHANG Qin-yu Journal of Applied Sciences    2017, 35 (2): 139-148.   DOI: 10.3969/j.issn.0255-8297.2017.02.001 Abstract （1110）      PDF（pc） （2044KB）（670）       Knowledge map    Save To design polar coded cooperation with high gain and flexible cooperation in a fading channel, systematic polar coded cooperation based on puncturing is investigated. It is shown that puncturing algorithms for non-systematic polar codes are also applicable to systematic polar codes. A quasi-uniform puncturing algorithm optimized by information bit refreezing is then applied to the systematic polar codes. Thus, systematic polar coded cooperation is proposed. Simulation results show that the proposed method significantly outperforms non-systematic polar coded cooperation. Taking the case in which the cooperation level is 50% as an example, 2.0~2.5 dB performance gain is achieved when the code length and code rate are 256 and 0.25, respectively. Reference | Related Articles | Metrics | Comments（0）

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Implementation and Verification of Improved Concatenated Code Based on Software-Defined Radio GAO Shu-li, CHEN Wei-gang, YANG Jin-sheng Journal of Applied Sciences    2017, 35 (2): 149-159.   DOI: 10.3969/j.issn.0255-8297.2017.02.002 Abstract （937）      PDF（pc） （1672KB）（395）       Knowledge map    Save A concatenated code combining an low-density parity-check (LDPC) code with a Reed-Solomon (RS) code, is designed based on the software-defined radio platform formed by universal software radio peripheral (USRP), which has compatible parameters with digital video broadcasting-terrestrial (DVB-T). Compared with the concatenated code combining a convolutional code with an RS code in DVB-T, the designed concatenated code obtains excellent error-correction performance, since LDPC performs better than the convolutional code, and the RS code can further eliminate error floor of the LDPC code. The designed code is implemented on a USRP platform. Its performance is tested in a wireless channel. The results show that high performance gain can be achieved by using the designed concatenated code as compared with the concatenated code in DVB-T. Reference | Related Articles | Metrics | Comments（0）

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Precoding for Up-link Multi-user MIMO Relay Systems with Feedback Delay SU Jun-xu, CHEN Xiao-min, HU Xu-jun, ZHU Qiu-ming Journal of Applied Sciences    2017, 35 (2): 160-170.   DOI: 10.3969/j.issn.0255-8297.2017.02.003 Abstract （902）      PDF（pc） （2008KB）（421）       Knowledge map    Save This paper proposes an optimal linear precoding scheme for uplink multi-user multiple-input multiple-output (MIMO) relay systems applicable to a channel with feedback delay and channel estimation errors. Limitations of the channel estimation method and the time delay of feedback link are considered. Design of transceiver is simplified as an optimal problem with precoding matrix variables, derived with a maximum power constraint at the relay station based on the minimum mean-square error (MMSE) criterion. The relay precoding matrix and decoding matrix are obtained, and the equalizer optimized with a linear iterative searching algorithm. Numerical simulation shows that the proposed scheme can effectively reduce the bit error rate of the system when channel feedback delay and estimation error exist. Reference | Related Articles | Metrics | Comments（0）

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Applying Gate Replacement Technique Based on Double Weights to Mitigate Circuit Aging ZHU Jiong, YI Mao-xiang, ZHANG Yao, HU Lin-cong, LIU Xiao-hong, LIANG Hua-guo Journal of Applied Sciences    2017, 35 (2): 171-180.   DOI: 10.3969/j.issn.0255-8297.2017.02.004 Abstract （819）      PDF（pc） （2565KB）（352）       Knowledge map    Save Negative bias temperature instability (NBTI) is a key factor affecting reliability of integrated circuits at the nanometer level. The NBTI effects increase transistor threshold voltage, cause aging of the circuit, and result in the circuit timing violations. To mitigate the NBTI effects of the circuit, we define delay weight and topology weight to identify critical gates more precisely. We also consider the case that the fan-in gate of a critical gate is INV. We take it as NAND1, and use NAND2 to replace INV. Thus the critical gates can be better protected. Experiments on ISCAS85 benchmark circuits based on a 45 nm transistor model show that, when the circuit timing margin is 5%, and the gate replacement technique based on double weights is used, the average delay improvement is 38.29% without considering replacement of INV. The average delay improvement is increased to 60.66% when considering INV replacement. Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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Screening of SAHS Snore Based on ERB Correlation Dimension HOU Li-min, SHI Dan, LIU Huan-cheng, ZHANG Wei-tao Journal of Applied Sciences    2017, 35 (2): 181-192.   DOI: 10.3969/j.issn.0255-8297.2017.02.005 Abstract （901）      PDF（pc） （8705KB）（308）       Knowledge map    Save This paper proposes a method for screening sleep apnea hypopnea syndrome (SAHS) by recording snore sound. Based on the equivalent rectangular bandwidth (ERB) scale used in psychoacoustics, the ERB correlation dimension (ECD) of snore is used to analyze and classify snores of different severity levels. For the training group, snore episodes were manually segmented and ECD features of snores were extracted to establish a Gaussian mixture model (GMM). The nocturnal snoring sound of the test group was validated to detect SAHS snores. The apnea hypopnea index (AHI) was estimated, to determine severity of SAHS. AHI is an average number of apneic events per hour of sleep. Compared with the polysomnography diagnosis that is a gold-standard, accuracy of SAHS severity reached 90%. The proposed method is useful in accessory examination of SAHS severity and for home uses. Reference | Related Articles | Metrics | Comments（0）

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Euclidean Double Bits Embedding Hashing for Image Retrieval LI Lei, CEN Yi-gang, ZHAO Rui-zhen, CUI Li-hong, WANG Yan-hong Journal of Applied Sciences    2017, 35 (2): 193-206.   DOI: 10.3969/j.issn.0255-8297.2017.02.006 Abstract （888）      PDF（pc） （18196KB）（218）       Knowledge map    Save We propose a double-bit embedding hashing method based on the Euclidean distance (DBE-E). Euclidean distance is used to measure similarity between the binary hash codes to better preserve similarity relations of the original feature space and improve retrieval precision. To speed computation, bit operation is used to calculate the Euclidean distance between the hash codes. It is 400 times faster than the traditional calculation method of the Euclidean distance for double-bit embedding of 64-bit hash code. Experiments on three image data sets show that the proposed method produces better results than other popular quantization strategies of hashing. Reference | Related Articles | Metrics | Comments（0）

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Blind Equalization with Adaptive Variable Step Sizes Based on Parallel Laguerre Filter CUI Lin, YANG Jun-an, WANG Wei, LIU Hui Journal of Applied Sciences    2017, 35 (2): 207-216.   DOI: 10.3969/j.issn.0255-8297.2017.02.007 Abstract （968）      PDF（pc） （8619KB）（252）       Knowledge map    Save A blind equalization algorithm with adaptive variable step sizes based on parallel Laguerre filter is proposed to overcome problems such as long tap coefficients, and high bit error rate (BER) caused by deep fading channels. By analyzing existing filter structures and blind equalization algorithms, the proposed algorithm replaces traditional tapped delay with Laguerre sequence to make tap coefficients shorter. Meanwhile, convergence is accelerated by using a decision-directed algorithm and a fractionally spaced structure. Since the step size has a great effect on convergence speed and residual error, different algorithms with variable step sizes are compared. Based on the comparison, a revised equalization algorithm structure is devised to achieve the most suitable step sizes for high-speed common data link (CDL). Compared with traditional blind equalization algorithms, experimental results show that the proposed method improves equalization performance and reduces BERs remarkably. Reference | Related Articles | Metrics | Comments（0）

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Building Facade Reconstruction on Sparse LiDAR Data Region LIU Ya-wen, QIN Su-shun Journal of Applied Sciences    2017, 35 (2): 217-225.   DOI: 10.3969/j.issn.0255-8297.2017.02.008 Abstract （1028）      PDF（pc） （10915KB）（284）       Knowledge map    Save A building facade is composed of regular and irregular geometric structures. When the prior or extracted rules of facade structure are used to reconstruct the sparse data area, unreasonable reconstructed geometric structures will appear. This paper presents a method for building façade reconstruction on LiDAR data sparse region by combining rule inference and laser data verification. Building facade reconstruction is first introduced, including initial model reconstruction from LiDAR data and refinement combining LiDAR data and images. The reconstruction method is discussed for data sparse region with a focus based on an analysis of façade regularity, prediction of missing geometry structures and verification with point cloud data. Experiments show that the method can effectively detect unreasonable reconstruction and improve reliability of facade reconstruction based on the data sparse region. Reference | Related Articles | Metrics | Comments（0）

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Data Stream Ensemble Classification Based on Classifier Confidence LIU San-min, LIU Tao, WANG Zhong-qun, XIU Yu, LIU Yu-xia, MENG Chao Journal of Applied Sciences    2017, 35 (2): 226-232.   DOI: 10.3969/j.issn.0255-8297.2017.02.009 Abstract （865）      PDF（pc） （877KB）（390）       Knowledge map    Save A weight computation policy based on confidence is presented to deal with the problem in the sub-classifier's weight in dynamic data stream ensemble classification. The policy fully considers influence of the sample on the weight of the sub-classifier. Uncertainty of the prediction result is described by information entropy, and relationship between the classifier confidence and the samples established. Thus, the computation method of classifier's confidence is defined. According to the requirements of dynamic data stream classification and traits of concept drift, a dynamic weight ensemble model is built by batch learning and time policy. Theoretical analysis and experimental results show feasibility of the presented schema, which is better than traditional methods. Reference | Related Articles | Metrics | Comments（0）

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Multi-candidate Set of Generalized Orthogonal Matching Pursuit Algorithm TIAN Jin-peng, LIU Xiao-juan, LIU Yan-ping, XUE Ying, ZHENG Guo-xin Journal of Applied Sciences    2017, 35 (2): 233-243.   DOI: 10.3969/j.issn.0255-8297.2017.02.010 Abstract （673）      PDF（pc） （8038KB）（573）       Knowledge map    Save A multi-candidate set of generalized orthogonal matching pursuit algorithm is proposed to improve precision of greedy algorithms for compressed sensing. Multiple atoms are chosen as multiple candidates based on correlation of the inner product of observation matrix and residual. In the iteration, the multiple atoms are added to the multiple candidate sets, resulting in fast convergence of the algorithm. The candidate set with the smallest residuals is chosen as the final support set so that the sparse signal is exactly rebuild. Compared with other algorithms, experimental results show that the proposed algorithm has better recovery performance and lower recovery complexity. Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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Steepest Approaching Method for Tracking Desired Thrust Vectoring of Rotor UAVs DENG Shi-qian, CHENG Wan-sheng, WANG Kai Journal of Applied Sciences    2017, 35 (2): 244-256.   DOI: 10.3969/j.issn.0255-8297.2017.02.011 Abstract （1024）      PDF（pc） （11103KB）（523）       Knowledge map    Save As for the trajectory tracking task of rotor UAVs, this paper proposes a fast approaching method based on the equivalent rotation vector of quaternion, to be used to optimize the control mode of trajectory tracking. The process is described as follows:when a thrust vectoring target is generated in the position control loop, the minimum rotation vector and minimum attitude change quaternion can be defined with this method. The desired attitude quaternion is then obtained, and provided to the attitude control loop to realize fast approaching to the desired thrust vectoring. Results of simulation and flight control system tests show that the proposed method enables thrust vectoring to track the target vector with an optimal path. Meanwhile, it can decrease the UAVs' attitude variation and tracking time. A trajectory tracking control solution is also designed by using the steepest approach method. Compared with other solutions without optimization, the solution given in this paper requires less computation. It is especially suitable for applications with low cost embedded controllers. Reference | Related Articles | Metrics | Comments（0）

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Adaptive Robust Control for Uncertain Non-affine Systems with State and Input Constraints CHEN Long-sheng, WANG Qi Journal of Applied Sciences    2017, 35 (2): 257-274.   DOI: 10.3969/j.issn.0255-8297.2017.02.012 Abstract （847）      PDF（pc） （10972KB）（389）       Knowledge map    Save Adaptive robust universal back-stepping control is presented for a class of uncertain non-affine systems with state and input constraints. The non-affine system is transformed to a time-varying system with a linear structure using the mean value theorem. The interval of time-varying uncertain parameters is calculated by considering all constraints. To handle the state constraints, a nonlinear mapping technique that maps the constrained states to a real number set is developed. Furthermore, bounded time-varying parameters and external disturbance are estimated using adaptive algorithms with projection. The estimation error is compensated by using a robust feedback technique. The controller is designed by combining back-stepping with a hyperbolic tangent function and a Nussbaum function. It can deal with the problems of input saturation and possible controller singularity caused by unknown control direction. Based on the Lyapunov stability theorem and the decoupled back-stepping method, semi-global stability of the close-loop system is proved. Simulation results show feasibility and validity of the proposed control schemes. Reference | Related Articles | Metrics | Comments（0）

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Journal of Applied Sciences    2017, 35 (3): 0-0.   Abstract （123）      PDF（pc） （28KB）（126）       Knowledge map    Save Related Articles | Metrics | Comments（0）

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Journal of Applied Sciences    2017, 35 (3): 0-0.   Abstract （388）      PDF（pc） （401KB）（176）       Knowledge map    Save Related Articles | Metrics | Comments（0）

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Performance Analysis of Coded Modulation Signal Based on Software-Defned Radio ZOU Jie, CHEN Wei-gang, YANG Jin-sheng Journal of Applied Sciences    2017, 35 (3): 275-287.   DOI: 10.3969/j.issn.0255-8297.2017.03.001 Abstract （811）      PDF（pc） （2724KB）（463）       Knowledge map    Save To evaluate the performance of coded and modulated signals in a wireless channel, experiments are performed based on the universal software radio peripheral (USRP). Performances of coding and modulation schemes using 8 phase-shift keying and three channel coding schemes, including turbo codes, binary low density parity check (LDPC) codes and non-binary LDPC codes, are compared and analyzed. To ensure accuracy of the apriori probability, phase ambiguity in the symbol of 8 phase-shift keying is detected and recovered based on frame synchronization sequences. An empirical characteristic function is used to estimate the channel noise variance. Furthermore, a priori probability is calculated from the recovered symbol and the estimated noise variance. Simulation and experimental results show that, with short code length, superior performance can be achieved with the three channel coding schemes, and non-binary LDPC codes performs better than binary LDPC codes and Turbo codes. Reference | Related Articles | Metrics | Comments（0）

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Resource Allocation Based on Genetic Algorithm and Particle Swarm Optimization for Cognitive OFDM Network DONG Li, SONG Xiao-qin, HAN Jie Journal of Applied Sciences    2017, 35 (3): 288-298.   DOI: 10.3969/j.issn.0255-8297.2017.03.002 Abstract （934）      PDF（pc） （6368KB）（585）       Knowledge map    Save For multi-user resource allocation in orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) networks, a resource allocation algorithm is proposed to maximize system capacity under the constraint of transmission power budget, interference threshold of primary users, and proportional fairness among secondary users. A subcarrier allocation scheme based on genetic algorithm (GA) is designed. Particle swarm optimization (PSO) combined with multistage punishment function is then used to power allocation. Simulation results show that the proposed algorithm can obtain a good system capacity close to the optimal method, and improve proportional fairness among secondary users with low computation complexity. Reference | Related Articles | Metrics | Comments（0）

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Channel Allocation of Femtocell Based on Heuristic Ant Colony Algorithm CHEN Jia-min, ZHU Qi Journal of Applied Sciences    2017, 35 (3): 299-308.   DOI: 10.3969/j.issn.0255-8297.2017.03.003 Abstract （958）      PDF（pc） （4454KB）（157）       Knowledge map    Save Considering a heterogeneous cellular network composed of macrocell and femtocell, this paper proposes a channel allocation method in femtocells by combining the graph theory and a heuristic ant colony algorithm. The proposed algorithm constructs adjacency matrix of femtocells using the graph theory, and acquires an available channel list of each femtocell according to signal to interference and noise ratio (SINR) of macro users and femto users. To achieve maximum average throughput of femtocells, a guide is provided to solve the heuristic ant colony algorithm using heuristic information and pheromone. Simulation results indicate that the proposed algorithm can improve the total system throughput while ensuring quality of service for both macro and femto users. Reference | Related Articles | Metrics | Comments（0）

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Modulation Recognition of Double Satellite Signals in Alpha-Stable Distribution Noise YANG Wei-chao, YANG Xin-quan Journal of Applied Sciences    2017, 35 (3): 309-316.   DOI: 10.3969/j.issn.0255-8297.2017.03.004 Abstract （995）      PDF（pc） （2196KB）（221）       Knowledge map    Save Modulation recognition algorithms of single signal based on second-order cyclic spectrum does not work in an Alpha-stable distribution noise environment. To deal with the problem, a recognition algorithm based on general second-order cyclic spectrum for double signals is proposed. Insensitivity of general second-order cyclic spectrum to Alphastable distribution noise is analyzed, and spectral properties of the double signals are then studied. Pulse spectral lines in the cyclic frequency domain of spectrum are extracted to be used as characteristic parameters for recognition. Modulation recognition of the double satellite signals is achieved by detecting the number of pulse lines. Simulation results show that the proposed algorithm has good performance in the two kinds of noise. Reference | Related Articles | Metrics | Comments（0）

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Self-Adaption MAC Protocol for M2M Network Based on Q-Learning XU Chang, WANG Cong, LIU Ling-ya, LI Ning Journal of Applied Sciences    2017, 35 (3): 317-325.   DOI: 10.3969/j.issn.0255-8297.2017.03.005 Abstract （660）      PDF（pc） （1545KB）（574）       Knowledge map    Save An adaptive medium access control (MAC) protocol Q-learning hybrid MAC (QH-MAC) is proposed for data collection application in machine-to-machine (M2M) networks. The QH-MAC enhances hybrid group MAC (HG-MAC) with an adaptive Q-learning based mechanism, in which the central node dynamically adjusts the COP duration according to the network load. The adaptive learning mechanism improves flexibility and the adaptability of the MAC protocol. QH-MAC is compared with carrier sense multiple access with collision avoidance (CSMA/CA), time division multiple address (TDMA) and HG-MAC by optimized network engineering tool (OPNET) simulations. The results show that HG-MAC is better than the others in terms of data rate, energy efciency and channel utilization. Reference | Related Articles | Metrics | Comments（0）

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Collaborative Filtering Recommendation Based on Double-Perspective of Users and Items CHENG Shu-lin, ZHANG Bo-feng, ZOU Guo-bing Journal of Applied Sciences    2017, 35 (3): 326-336.   DOI: 10.3969/j.issn.0255-8297.2017.03.006 Abstract （905）      PDF（pc） （2488KB）（283）       Knowledge map    Save Traditional collaborative fltering (CF) recommendation approach has a serious problems such as insufcient usage of single perspective information, unsatisfactory accuracy and sensitivity to data sparsity. To solve these problems, a CF recommendation method based on double-perspective of users and items is proposed by considering information of similar users and similar items. According to the dialectic principle, fusion similarity of items is given by combination of inner-factors and outer-factors of the item. This way, the item similarity and user similarity can be effectively measured. The measurement is robust against data sparsity in the approach of CF recommendation based on double-perspective of user and item. Several experiments are carried on benchmark datasets. The results show that the proposed CF recommendation method based on double-perspective of users and items outperforms several other typical CF approaches. Reference | Related Articles | Metrics | Comments（0）

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Analysis and Spatio-temporal Dynamic Simulation of Land Use Change CAO Qing, ZHANG Peng-lin, LI Wei-qing, LUAN Yi Journal of Applied Sciences    2017, 35 (3): 337-345.   DOI: 10.3969/j.issn.0255-8297.2017.03.007 Abstract （1003）      PDF（pc） （8313KB）（544）       Knowledge map    Save A simulation model on the spatio-temporal pattern of land use change is designed with conversion of land use and its effects at small region extent (CLUE-S) as a modeling framework based on analyses of the rate, degree, and regional difference of land use change. The method is used to perform dynamic simulation of land use of Tianjin in 2020 to predict the change trend of land use. Simulation results show that the proposed method can provide a guide to the land use planning and management. Reference | Related Articles | Metrics | Comments（0）

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Analysis of Expansion of Port Cities in Hainan Province Based on Impervious Surface BI Sen, WANG Heng, ZHANG Li, LI Tong, LIU Dong, HAN Rui-dan Journal of Applied Sciences    2017, 35 (3): 346-354.   DOI: 10.3969/j.issn.0255-8297.2017.03.008 Abstract （1087）      PDF（pc） （9725KB）（263）       Knowledge map    Save Based on Landsat TM and OLI data, integrating V-I-S and the linear spectral mixture model and some remote sensing indices such as NDBI and SAVI, this study derives impervious surface information of Haikou and Sanya of Hainan Province, and analyzes their temporal and spatial variations. During the past 15 years (1999～2015), impervious surfaces of both cities expanded from coastal areas to inland. The impervious surface of Haikou increased mainly in the southern and western areas, whereas that of Sanya increased at varied directions. As urbanization of both Haikou and Sanya proceeded at a high speed, proportions of impervious surface of these two cities have doubled. Population, GDP and impervious surface of both Haikou and Sanya rises every year, in which population increases slowly and steadily, while GDP and impervious surface increases signifcantly. By integrating a linear spectral mixture model and SAVI and NDBI indices, interference from bare soil and saline-alkali land to the information of impervious surface can be reduced, and estimation accuracy of the impervious surface improved. Reference | Related Articles | Metrics | Comments（0） Cited: Baidu(1)

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