bluuebunny/crossref_metadata_2025 huggingface dataset:
Research and Application of Big Data in E-government
Authors: Naili Liu , Lei Ma
Published: August 2019

The wide use of modern electronic information technology, represented by big data technology, has brought people into the era of big data. Big data is affecting our work, life, even economy and the development of the society. Nowadays, the application of big data technology in e-government speeds up the development of e-government, which is important for the overall construction of e-government. This paper summarizes the application of the big data, introduces the application of big data technology in e-government. Then this paper analyzes the current situation and problems of e-government development. Finally this paper proposes the solutions of big data platform in e-government.
Intelligent Routing Scheme for SDN Satellite Network Based on Neural Network
Authors: Sun Weichao , Liang Jun , Xiao Nan , Ding Ran , Zhang Zhenhao
Published: August 2019

In view of the existing SDN-based satellite network system, the tri-state content-addressable memory (TCAM) space occupied by the flow table is increasing, and the search and matching of flow entries are complicated, resulting in reduced routing and forwarding efficiency, which cannot meet the needs of diverse application requirements. Therefore, an intelligent routing scheme of SDN satellite network based on neural network (IRSSN) is proposed. The controller acquires the transmission mode of the data stream by training the neural network (NN), and replaces the flow table with the trained NN. An intelligent routing mechanism based on the orthogonal polynomial (Chebyshev) neural network is proposed. The switch predicts its forwarding path according to the traffic type of the data stream to meet the QoS requirements of the satellite network application. The simulation results show that IRSSN significantly reduces the occupied TCAM space and improves routing efficiency.
Optimization of DTC algorithm based on distributed parameter modelling of PMSM
Authors: Shi Bufan
Published: August 2019

Accurate mathematical model is the basis and precondition of electric motor control. The existing motor model under concentrated parameters is difficult to describe the harmonic and nonlinear characteristics of the motor, while the motor model under distributed parameters can accurately describe the torque and flux characteristics of the motor precisely at all working points, which provides the foundation for model-based motor control. The stator flux and torque observer have an essential influence on the performance of direct torque control (DTC) for PMSM. The concentrated parameter model of PMSM considering only the fundamental wave vector of the magnetic field for DTC will have obvious deficiencies in the performance such as torque ripple. This paper therefore uses the reconstructed magnetic co-energy (MCE) model to establish a torque and flux observer based on distributed parameters, which is introduced into the DTC algorithm of PMSM as an observer. The optimized DTC algorithm makes full use of the flux and torque harmonic description capabilities of the distributed parameter model, which improves control performance. The superiority of the distributed parameter observer is verified by simulation and bench test.
Electromechanical-Electromagnetic Hybrid Simulation Based on E-Tran Plus
Authors: Cui Yong , He Xiang-xiang , Yang Xiu , Wang Wei-hong , Cao Liang , Jin Ming-jie
Published: August 2019

The simulation software E-Tran Plus is used as the interface, and the mature software PSCAD and PSS/E are combined to form the electromechanical-electromagnetic hybrid simulation platform. The function and principle of the simulation software are introduced in detail, and a simple electromechanical-electromagnetic hybrid simulation and pure electromagnetic simulation research are compared through a small system. The theoretical and simulation results show that the electromechanical-electromagnetic hybrid simulation using the new software has higher accuracy. The hybrid simulation model based on E-Tran Plus can better reflect the dynamic characteristics of the AC system, and it is closer to the actual project, which provides an important reference value for the research of electromechanical-electromagnetic hybrid simulation of large-scale AC/DC grid.
The influence of aggregate gradation on the fresh and hardened concrete properties
Authors: Figmig R , Kovac M
Published: August 2019

This experimental study is focused on the aggregate gradation impact on the properties of fresh and hardened concrete. For the experiment, 9 mix design were prepared with the constant content of cement, effective water, plasticizer and aggregate. The variable factor is represented by different proportions of 4 fraction (0/0.7, 0/4, 4/8, 8/16). Consistency by slump and flow table in time, compressive strength, water absorption and density were measured. Some significant differences were observed. Consistency by the slump test varied from 0 to 170 mm after 5 minutes and from 0 to 50 mm after 30 minutes of concrete mixing. Consistency by flow table varied from 340 to 530 mm after 5 minutes and 320 to 460 mm after 30 minutes. Standard compressive strength varied from 50.8 to 61.6 MPa. Water absorption varied between 4.7 and 5.9 mass % and density from 2380 to 2440 kg.m−3.
Hydraulic assessment of flood protection measures proposal
Authors: Janík A
Published: August 2019

Ensuring flood protection is a never-ending task, therefore there is always something to improve or add. Nowadays there is a big boom in detention reservoir projecting for smaller river basins in Slovakia. This paper focuses on flood protection proposal for village Vel’ká Lúka located in the central part of Slovakia. The contribution deals with the hydraulic modelling of present state of river Lukavica channel and its capacity and also proposed flood protection measures. According to geodetic survey and flow rate measurements a 5 km long partially calibrated mathematical model of the Lukavica River has been created. For this purpose, the HEC-RAS software has been used. After evaluation of the flow rate capacity through the village, a flood protection measure – detention reservoir – has been proposed using designed flood wave provided by Slovak Hydro-meteorological Institute (SHMI). According to transformation of flood wave computation, specific parameters of necessary flood protection measures were determined.
Water transport in materials of historical buildings
Authors: Jaroš P , Vertal’ M
Published: August 2019

The historic buildings renovation is one of the unwritten obligations of every nation. In the territory of the Slovak Republic there is quantity of the historical buildings which are from different architectural periods, which we can find not only in the squares of the bigger cities, but also in a wide areas. The technical conditions of these buildings describe our relationship with which we look at them. At the present, many historic buildings are restored, but more are left untouched and without maintenance. Incorrect construction details, but also inappropriate additional building adaptation, cause degradation of the masonry and surface layers. Absence of the water-insulating waterproofing against capillarity allows the water to be transported into vertical structures and with it transport water-soluble salts from the subsoil. Increasing mass of the humidity by capillary transport and crystallization of water-soluble salts in porous materials causes visible defects on the surface of the structures. Laboratory measurement of the humidity and capacity of the water-soluble salts in a historic building point to the impact of the segmentation and using of the building. Different values of the taken samples define critical places that necessitate additional remediation. Suggestion of the remediation influences diversity of the materials which are used and their material characteristics. For the water transport analysis, it is necessary to know the transmission parameters of the water of the historical structures. Determination of the humidity coefficient is possible by the water absorption coefficient and the value of the capillary humidity. The measurement is carried out by an experiment of the unidirectional capillarity by the laboratory instrument.
The search for an optimal architectural shape using wind performance analysis
Authors: Kabošová L
Published: August 2019

The rapid enhancement of computers’ power and the boom of open-source software development have offered a broad range of possible applications in architectural design. Grasshopper is a visual programming language developed for the 3D CAD modeling program, Rhinoceros. Utilizing Grasshopper’s free software extensions, it is possible, among other things to evaluate the environmental performance of architecture in the early conceptual stage. This paper introduces a novel approach to architectural designing presented in a case study in the extreme environment of Reykjavik’s airport. The shape of the airport building formed within this case study can be parametrically changed, and the performance of the various shape modifications in the wind can be tested. Using Ladybug and Swift for Grasshopper, the wind situation at the airport is analyzed, and the aerodynamic shape of the proposed airport building is evaluated in the prevailing easterly winds. The proposed bio-climatic architectural design approach incorporates the surrounding micro-climatic conditions, wind in particular, as a driving factor already in the phase of first design ideas. The parametrically developed airport is formed with regard to the pedestrian wind comfort, as well as airport traffic safety.
Update on Research on Transparent Wood
Authors: Karl’a V
Published: August 2019

This article focuses on various methods of creation of transparent wood, which are derived of the original invention of transparent wood fabrication and describes the advantages of each method, newly obtained properties of the composite materials and suggestions of its possible use in building industry and architecture.
Study of zinc removal from water solutions using hornbeam wooden sawdust
Authors: Kovacova Z
Published: August 2019

The polluted water from an industry, in particular with heavy metals, aromatic molecules and dyes, is a serious environmental problem because their potential environment toxicity. Therefore, there is a need to develop methods that can remove toxic contaminates from wastewaters. The sorption process is one of the most popular methods for the environment treatment. Adsorption on low-cost materials is studying with great interest by researchers in last years. Hornbeam sawdust is a natural resource and an inexpensive material which can be used for water treatment. In this study, the hornbeam sawdust was used as for the removal of zinc from an aqueous solution. Fourier transform infrared spectroscopy (FTIR) was used to determine functional groups of sawdust. The pH decreased from 6.3 to 5.8 during 2 h and in case of 24-hours experiment on the value of 5.4. Hornbeam sawdust had efficiency of zinc removal from aquatic model solutions height than 75 % which means that there is significant potential for sawdust as a sorbent material for heavy metals removal from water.
Fracture response of cement-based composite with spherical glass aggregate exposed to high temperatures
Authors: Rozsypalová I , Kumpová I , Majda T , Keršner Z , Štancl P
Published: August 2019

This paper concerns an investigation into the effects of high temperatures acting on specimens made from specially designed fine-grained cement-based composite with spherical glass aggregate. The experimental programme was carried out on four sets of beam specimens with the dimensions 20 × 40 × 200 mm. The specimens were thermally loaded to pre-set temperatures of 100, 200 and 400 °C, after which these temperatures were maintained for 60 minutes (one of the sets contained three reference specimens which were placed in a laboratory at a temperature of 20 °C and were not exposed to heat). After the temperature loading had been performed, the specimens were left to cool down to ambient temperature. After that, fracture tests were used to determine the degree of damage caused to the specimens by temperature loading. Three-point bending tests were conducted on the previously loaded beam specimens, which were notched to provide them with an initial stress concentrator using a diamond blade saw before testing. The depth of the initial edge notch on the bottom side of the specimen was approximately 1/3 of the total specimen depth. The span length was 180 mm. Fracture response was evaluated via load versus deflection diagrams. The monitored parameters were modulus of elasticity, effective fracture toughness and specific fracture energy. Informative compressive strength values were also determined. Selected specimens were investigated using X-ray micro-tomography (micro-CT).
Cost management of building constructions and works through knowledge-based database
Authors: Smetanková J , Mandičák T
Published: August 2019

Civil engineering represents an important economical segment. Higher pressure on raising effectiveness, productivity and automation is perceived in society. An important factor that influence raise of effectiveness and productivity is cooperation support between participants of building sector. Individual participants are connected between each other and they are allowed to gain, collect, share, rate and use available information’s in required quality and required time. For this purpose, a lot of supporting tools are created and these dispose with automation features, such as knowledge system or knowledge database. One of the most important processes in building’s life-cycle is cost setting through the whole life-cycle. Correct cost setting is an important indicator in deciding about size, shape, equipment and also on building realization itself. In building’s life-cycle, besides economical aspect that is represented by costs connected with individual life-cycle phases, it’s also important to consider other parameters that greatly influence building method and using or disposal of the building. This article, based on mentioned facts, brings a proposal of methods and structure to create knowledge database, that brings user a tool that dispose with information’s needed for deciding about construction solution of future building and allows to manage costs for building operations and building works.
Analysis of current situation in field of LCA.
Authors: Tomková Ž , Vilčeková S
Published: August 2019

With building industry and buildings large consumption of energy and environmental impact on planet, it is crucial to minimalize future consequences of our decisions. With help of LCA analysis, we can evaluate current situation and predict future impact of the design. This allows us to make better decisions in design stage of building process. There needs to be a lot of analysis to relevantly compare different types of buildings, in different environment and using different materials. This paper concentrates on current situation in this field of study, in global scale and with focus on Slovak republic.
Humidity and salt sensor based on CdSSe nanowire chip
Authors: Lu Tianqi , Zhang Min , Guo Shuai , Liu Ruibin
Published: August 2019

The humidity and salt sensitive characteristics of sensor based on polyimide coated CdS1-xSexsemiconductor alloy nanowire chip have been investigated. The composition-graded CdS1-xSexnanowire chip with large size shows excellent photo-sensitivity and stress sensitivity, synthesized by a simple CVD method and its composition can be gradually tuned from CdSe to CdS. The conductivity of the sensor showed good humidity response characteristics with a maximum responsivity (dI / I) of 85% at 80% RH. In addition, the current decreases linearly with increasing salt concentration, indicating that the chip sensor has good salt responsiveness and the best salt responsiveness is 80%. The RH dependent resistance upon illumination exhibits good linearity (R2=0.9948) to guarantee the high prediction accuracy. In addition to good moisture and salt response characteristics, the sensor also exhibits excellent stability and reproducibility.
An Improved Algorithm for TDOA Trajectory Tracking
Authors: Beibei Li , Zhanjun Hao , Xiaochao Dang
Published: August 2019

In a precision positioning system, one important source of positioning error is the clock synchronization problem, which is caused by multiple base stations. Therefore, eliminating the clock synchronization problem in a no-line-of-sight (NLOS) environment plays an important role in reducing errors in a positioning system. To address this problem, this study designs a practical experimental environment and proposes the concepts of Time Difference of Arrival (TDOA) and non-line-of-sight-Time Difference of Arrival (N-TDOA). First, the improved TDOA algorithm is used to determine the tag’s position; second, the tag’s trajectory is drawn at different times; then, a map of the monitored area is loaded, and the tag trajectory is displayed in the actual experimental environment. The experimental results show that the N-TDOA algorithm synchronizes the base stations at the algorithmic layer; thus, deploying network cables or wires to achieve clock synchronization is unnecessary: wireless deployment can be used. In an NLOS environment, the N-TDOA method significantly improves the positioning accuracy compared with that of other algorithms, which facilitates further trajectory tracking research. Overall, the proposed approach improves both the accuracy and stability of trajectory tracking.
Shielding effectiveness analysis of a rectangular enclosure with wire mesh covering
Authors: Chen Longlong , He Ri , Jiao Chongqing , Hu Yifan
Published: August 2019

Analytical model has been developed for the shielding effectiveness of a rectangular enclosure with wire mesh covering. The aperture covered by wire mesh is replaced by an equivalent impedance which contains the surface resistance of the wire mesh. Based on the transmission line theory, the enclosure is modelled as a length of rectangular waveguide ended with a short circuit, then the shielding effectiveness (SE) of the enclosure can be calculated. By comparing the calculation with the full-wave simulation software, the proposed method is validated.
The design and Implementation of Image Transmission System for Mobile Devices Stabilizers
Authors: Wu Lingyu , Song Shuxiang , Song Wenwen , Huang Jinyan , Xia Haiying
Published: August 2019

In view of the application of PTZ system in photographic equipment, we design a wireless image transmission system for photographic equipment and mobile equipment. Hi3516A is the main control chip of the system, and the second connection interface is connected with the photographic equipment to collect the relevant data that recorded by the photographic equipment, and the data is encoded and encapsulated by the processing module. The first connection interface adopts 2.4G wireless radio transceiver module, which connects with the mobile device wirelessly to transmit picture data information to the mobile device, and realizes wireless image transmission from the photographic device to the mobile device. The test of wireless picture transmission system shows that the picture transmission system has fast transmission rate, high real-time performance and wide application range.
Research on Product Safety Assessment Method Based on Spacecraft Assembly Process
Authors: Liu Zhibin , Li Zhiming , Lu Yi , Wang Yu
Published: August 2019

Based on the analysis and identification of risk factors in spacecraft assembly process, the safety evaluation model of spacecraft assembly process is constructed. Form a multi-dimensional safety evaluation parameter system. After investigating the safety evaluation methods in related fields, the method of combining the analytic hierarchy process (AHP) with the fuzzy evaluation method is determined to carry out the evaluation work, and the comprehensive safety evaluation results are obtained. The result of the evaluation is accurate and objective, which lays a solid foundation for the safety evaluation of spacecraft assembly process products.
Design of B2B E-commerce Platform Based on SOA Architecture
Authors: Li Jiang
Published: August 2019

With the rapid development of information technology and computer networks, internnet-based e-commerce has also emerged, and has achieved tremendous development in recent years. Most enterprise systems are developed based on heterogeneous platforms and different information standards. The interaction and integration between enterprises is very difficult, and the traditional distributed architecture can not solve the current needs. Service-oriented architecture is a new generation of distributed software architecture that solves the above problems. As a new generation of distributed software architecture, it not only improves the reusability of software, but also achieves good scalability. This paper uses the SOA architecture to design the e-commerce platform, and designs the interface service to realize the service composition of the e-commerce platform.
An universal GMMs-based sample strategy and collision checker for robot motion planning
Authors: Zha Fusheng , Dai Xuehan , Guo Wei , Liu Yizhou
Published: August 2019

The sampling-based motion planning methods acquire obstacle information by performing collision detection for a large number of samples, which can effectively solve autonomous obstacle avoidance problem in the high-dimensional configuration space. In order to improve the efficiency of planning, this paper proposes a new adaptive sampling strategy and collision checker based on Gaussian Mixture Models(GMMs): For the "narrow corridor" problem, the sample set obtained by Gaussian sampling strategy of adjustable standard deviation is used to train the GMMs. The models fitting the target area in the manipulator configuration space can guide the adaptive sampling; using the GMMs fitting the obstacle region to predict the collision probability of the samples rapidly, and using Greedy K-means initializes the EM algorithm to improve the fitting accuracy of the model. Finally, the sampling strategy and collision detection method are combined with various sampling-based motion planning algorithms, and multiple simulation experiments are carried out to verify the results. The results show that the proposed method has significantly improved planning efficiency compared with the traditional method.
A method of evaluating performance of missile three-loop autopilot
Authors: Sun Xueyang , Chen Wei , He Li
Published: August 2019

Three-loop autopilot is widely used in missile acceleration control. The parameters of the autopilot influence the performance of the autopilot in both frequency-domain and time-domain. However, what we know about the influences are quite qualitative, such as that angular speed feedback parameter provides additional damping to the missile. Problems appear if the control parameters cannot satisfy all the requirements of the autopilot. Based on the qualitative conclusions, it is impossible to meet the frequency-domain or time-domain performance requirements by adjusting the control parameters. This paper provides a method to obtain the first order time constant of the autopilot and frequency-domain performance such as amplitude margin and phase margin of the autopilot. The method can be used to make a rapid evaluation of missile three-loop autopilot performance and provides theoretical guidance to optimize control parameters.
A Novel Wheel Skid Control Based On Motor Energy Distribution Model
Authors: Zhou Qiang , Yin Dejun
Published: August 2019

How to realize wheel slip control with parameters that can be measured and not relying on hardware precision is a difficult problem in vehicle traction control. From the point of view of energy transfer, this paper uses the feature that the rotational kinetic energy of the wheel increases abnormally when slipping, and proposes a wheel slip control method based on the motor energy distribution model. This method only requires the motor phase voltage, phase current and wheel speed that are easy to measure. In this paper, a complete vector control model of permanent magnet synchronous motor is established, and a PI control algorithm framework is built based on one-wheel vehicle model. The simulation results verify the effectiveness of the proposed algorithm.
Research on Variable Structure High Voltage Power Supply Control Strategy Based on Predictive PI control algorithm
Authors: Li Jiaqiang , Huang Yiyun , Pan Shengming , Feng Hulin , Wang Denghui , Lei Hong
Published: August 2019

The research and verification of a variable structure high voltage power supply unit and its control strategy are introduced. According to the mathematical modeling method, the variable structure system is linearized equivalent analysis and closed-loop system design. The actual parameter verification and theoretical verification of the system are carried out by means of experimental identification, and the research of subsequent control strategies is guided. According to the analysis results and the dynamic parameters of the power supply, a control strategy based on Predictive PI is proposed and simulated. In addition, in order to realize the actual verification of the power supply control algorithm, a power controller based on the ARM and FPGA architecture is designed to be applied to the system. Experiments show that the control strategy can solve the complex variation of the nonlinear and variable structure of the power supply under dynamic conditions, and ensure that the system completes the established parameter indicators.
Research on Programmable Logic Controller Security
Authors: Wu Haolan , Geng Yangyang , Liu Ke , Liu Wenwen
Published: August 2019

With the convergence of computer technology and industrial networks, attackers are not limited to attacking only individual users’ computers, turning to attack industrial control systems that can cause major infrastructure problems. Programmable Logic Controllers (PLC) are the core components of industrial control systems. Its safety has a profound impact on the safety of the entire industrial system. This paper firstly classifies the security research of PLC according to the structure and function, and expounds the existing security defects of PLC from the aspects of firmware security, operation security and program security. Then it summarizes and analyzes four types of security protection measures: the integrity of verification firmware, protocol security encryption, code formal verification, and program security defence detection. Finally, according to the overall safety of the industrial system and the actual development of the current PLC, we discuss the development trend of safety research.
Joint Resource Allocation and Power Control Algorithm for D2D Based Train to Train Communication
Authors: Huan Luo , Xiaojuan Liu , Yingying Xin , Chunlin Fang
Published: August 2019

The next generation Communication based train control (CBTC) system has many new features, one of which is the introduction of train-to-train (T2T) communication. T2T communication can be realized by device-to-device (D2D) communication based on long-term evolution (LTE). However, D2D communications may generate interference in the system if not designed properly. In this paper, a joint resource allocation and power control algorithm is proposed to maximize the overall network throughput while guaranteeing the quality-of-service (QoS) requirements for both T2T links and cellular links. The algorithm has two steps. The first step is to allocate resources according to channel state information (CSI), the second step is to allocate power while maintaining system performance. Simulation results show that compared with random resource allocation, proposed approach provides a significant improvement in the system performance.
Multi-objective Comprehensive Optimization of Distribution Network considering the randomness of DG
Authors: Gao Haishu , Ji Xingquan , Li Kejun , Wu Na
Published: August 2019

In recent years, distributed generation technology develops rapidly due to its’ flexible and environment-friendly nature. In order to better analyze the impact of DG on the economics and safety of distribution networks, a probability model for random load, micro gas turbines and photovoltaic power generation system is formulated. With the objective of minimizing the network loss, lowest static insecurity probability, and the lowest cost of purchasing electricity, the optimization of distribution network with distributed generation is carried out by adjusting the distribution network topology and the output of controllable DG. The stochastic power flow is combined with the particle swarm optimization algorithm to obtain the Pareto non-inferior solution set, and then the subject is selected to obtain the optimal solution. Finally, simulations are carried out on the IEEE 33-bus test system and it is shown that the optimized network can effectively reduce the network loss and static insecurity probability on the basis of low cost of purchasing electricity.
An Inproved Up-scaling Algorithm Combined TSA and PSF
Authors: Bai Xuejiao , Sang Lingzhi , Bai Guichen , Kang Hongxia , Liu Zhen
Published: August 2019

Taking the Guanzhong Plain of Shanxi Province as the research area, the combine method of trend surface analysis method (TSA) and point spread function (PSF) (TSA+PSF) were used to up-scale the vegetation temperature condition index (VTCI) retrieved from Landsat 8 images (Landsat-VTCI) from a finer resolution to a coarser resolution. The up-scaled results were compared with VTCI images retrieved from Aqua MODIS (MODIS-VTCI) to provide technical support for the comprehensive application of drought monitoring results on two spatial scales. Meanwhile, a range of indicators, such as the semivariogram function (SVF), the structural similarity (SSIM), the correlation coefficients (r), root mean square errors (RMSE) were used to systematically compared the up-scaled methods. The results show that TSA+PSF performed better than TSA in terms of SSIM, the correlation and RMSE, the up-scaling model TSA+PSF has the higher accuracy, and it is more effective and robust than TSA. The model that uses PSF to analyze trend surface constructed by TSA is an improvement for up-scaling Landsat- VTCI images from a finer resolutions to a coarser resolutions.
Application Research of Banker Algorithm in Teaching Arrangement in Independent College
Authors: Jiang LI
Published: August 2019

Independent colleges are an important part of private higher education. There are many kinds of elective courses for undergraduates. Students are multi-disciplinary and have a large number of students across the grades. The limited resources at the end of the semester are facing enormous challenges. The banker algorithm is a dynamic strategy to eliminate deadlock algorithms. It can effectively and reasonably arrange the resources already in the system. This paper mainly discusses the application of the algorithm in the course scheduling system for the elective course classroom arrangement, so that each classroom can get full and reasonable application.
An improved index for clustering validation based on Silhouette index and Calinski-Harabasz index
Authors: Wang Xu , Xu Yusheng
Published: August 2019

The evaluation of clustering effects has been an important issue for a long time. How to effectively evaluate the clustering results of clustering algorithms is the key to the problem. The clustering effect evaluation is generally divided into internal clustering effect evaluation and external clustering effect evaluation. This paper focuses on the internal clustering effect evaluation, and proposes an improved index based on the Silhouette index and the Calinski-Harabasz index: Peak Weight Index (PWI). PWI combines the characteristics of Silhouette index and Calinski-Harabasz index, and takes the peak value of the two indexes as the impact point and gives appropriate weight within a certain range. Silhouette index and Calinski-Harabasz index will help improve the fluctuation of clustering results in the data set. Through the simulation experiments on four self-built influence data sets and two real data sets, it will prove that the PWI has excellent evaluation of clustering results.
Path Planning Research Based on An Improved A* Algorithmfor Mobile Robot
Authors: Xin Wang , Wanlin Lu , Chao Feng , Likai Hao
Published: August 2019

With the development of technology, the path planning technology of mobile robots has received extensive attention. The principle and process of A* algorithm are outlined. Because there are many break points in the A* algorithm, the path is not smooth and there are too many problems in searching for grid points. So we need improve the A-star algorithm. Firstly, in order to reduce the number of search grid points, a threshold value N is added to the openlist. If the number of search times is greater than N and the first node inserted is not expanded, the node is set to the highest priority. Secondly, we use the path planning based on the combination ofFloyd algorithm and A* algorithm to remove redundant nodes and reduce the sharpness of the breakpoints. Finally, the geometric optimization process results in a smooth path. Simulations verify that the improved A* algorithm reduces the path length and the path is smoother, more suitable for robot navigation.
Simulation and Experimental Research on Underwater Target HBT Interference Positioning Method
Authors: Zou Jing , Nie Lei , Jiang ChuanKai , Liu Mengran
Published: August 2019

To realize the positioning of underwater sound sources, a target positioning method based on acoustic field HBT interference is proposed. The precision of HBT interferometric target locating principle is verified by simulation under different parameters. The positioning effect is simulation analyzed at different frequencies with multiple sound sources. The results show that the position of the sound source can be found accurately by this method for single frequency source and multiple sources. At the same time, the positioning experiment in lake is carried out. The results verify the correctness of HBT positioning method and realize the orientation of single and multiple frequencies with the level of 180 dB which the distance of the sound source is 59 meters.
Research on the College Students’ Ideological and Political Education in the vision of the Internet Plus
Authors: Zhao Guiyang
Published: August 2019

The technological revolution has pushed mankind into a new era -- the "Internet plus" era. With powerful functions and super charm, the Internet affects the development of human society. It also brings new opportunities and challenges for the college students’ ideological and political education. In the era of "Internet plus", it is a great responsibility and a glorious mission for ideological and political education. Colleges need constant self-development and innovation. Only in this way can we better serve the ideological and political education. This paper first analysis the characteristics of the Internet from the perspective. And then this paper explains the problems of ideological and political education in the Internet plus era with the method of social investigation. Finally, this paper puts forward the measures of ideological and political education mode reform and innovation.
Face recognition method with feature fusion and error feedback
Authors: Yeping Fan , Yu Li , Desheng Yang , Tao Wan , Dong Ma , Dian Jiao , Yiting Cai , Mengxian Chen
Published: August 2019

A face recognition method with feature fusion and error feedback is proposed to imitate human cognition process. The intelligent recognition mode with multi-level feedback from global to local and from coarse to fine is implemented. Firstly, based on the idea of feedback control, a multi-level feedback model of face recognition with performance index constraints and supervised learning under finite domain is established. Secondly, based on entropy theory and Stochastic Configuration Networks (SCN), a facial feature space and face image classification network model with multi-feature fusion and sufficient separability under certain feature performance conditions are established from the perspective of information theory. Thirdly, based on entropy theory and error theory, the face recognition error representation and calculation model under certain feature performance conditions is established. Finally, the adjustment index of facial feature performance based on recognition error is constructed, and the face recognition algorithm with feature fusion and error feedback is given out. Test and comparison experiments show that our method is effective and feasible.
Parameter Estimation via Deep Learning for Camera Localization
Authors: Chong Mina , Li Qiming , Li Jun
Published: August 2019

This paper proposes a method based on deep learning to estimate parameters for camera localization. The parameters are 6-DOF camera pose and regressed from a single RGB image by an end to end convolution neural network. The proposed network makes use of batch normalized method, which relieves the disappearance of gradient, leading to drastic improvements in convergence speed. In addition, inspired by decomposing convolutions, the network breaks large convolutions into more small convolutions to cascade, which reduces the computational complexity, and enhances network feature representations owing to adding a layer of convolution. This CNN-based method is able to learn effective feature for camera localization in state of motion blur and illumination changes, while the traditional SHIF-based methods fail. Experimental results on both indoor and outdoor public datasets show the improved network achieves an increase in accuracy, and outperforms with the compared methods.
An Improved Approach based on Balanced Keyword Weight to Traceability Recovery
Authors: Wang Xinye , Cao Qinghua , Sun Qing
Published: August 2019

Software traceability recovery has become more and more important to the software life cycle recent days with the increasing complexity of software system. However, it is a tedious and error-prone task by manual. Many researchers have devoted themselves in building and predicting traceability links. In this paper, we approach a novel method to calculate text similarity and improve our results by a learning to rank method. And a couple of experiments are conducted to verify our method.
Circadian Blood Pressure Variations Computed From 1.7 Million Measurements in an Acute Hospital Setting
Authors: Mahdi Adam , Watkinson Peter , McManus Richard J , Tarassenko Lionel
Published: August 2019

BACKGROUND

Knowledge of the circadian blood pressure (BP) variations in the acute hospital setting is very limited.

METHODS

This is a retrospective analysis of BP data for in-hospital patients stratified by age and sex. We used data collected with the help of a standardized electronic health record system between March 2014 and April 2018 on the adult general wards in 4 acute hospitals in Oxford, UK.

RESULTS

A total of 41,455 unique patient admissions with 1.7 million sets of vital-sign measurements have been included in the study. The typical 24-hour systolic BP profile (dipping pattern during sleep followed by a gradual increase during the day) was only seen in the younger age groups (up to 40–49 for men and 30–39 for women). For older age groups, there was a late nocturnal rise in systolic BP, the amplitude of which increased with age. The late nocturnal BP rise above the age of 50 was seen whether or not the patient was treated for or previously identified with hypertension.

CONCLUSION

Hospitalized patients’ circadian patterns of BP largely mirror those found in the community. High-quality hospital data may allow for the identification of patients at significant cardiovascular risk through either opportunistic screening or systematic screening.
Performance of gene expression analyses using de novo assembled transcripts in polyploid species
Authors: Chen Ling-Yun , Morales-Briones Diego F , Passow Courtney N , Yang Ya
Published: August 2019

Motivation

Quality of gene expression analyses using de novo assembled transcripts in species that experienced recent polyploidization remains unexplored.

Results

Differential gene expression (DGE) analyses using putative genes inferred by Trinity, Corset and Grouper performed slightly differently across five plant species that experienced various polyploidy histories. In species that lack recent polyploidy events that occurred in the past several millions of years, DGE analyses using de novo assembled transcriptomes identified 54–82% of the differentially expressed genes recovered by mapping reads to the reference genes. However, in species that experienced more recent polyploidy events, the percentage decreased to 21–65%. Gene co-expression network analyses using de novo assemblies versus mapping to the reference genes recovered the same module that significantly correlated with treatment in one species that lacks recent polyploidization.

Availability and implementation

Commands and scripts used in this study are available at https://bitbucket.org/lychen83/chen_et_al_2018_benchmark_dge/; Analysis files are available at Dryad doi: 10.5061/dryad.4p6n481.

Supplementary information

Supplementary data are available at Bioinformatics online.
Comparison of Real-World Treatment Outcomes With Vedolizumab Versus Infliximab in Biologic-Naive Patients With Inflammatory Bowel Disease
Authors: Patel Haridarshan , Latremouille-Viau Dominick , Burne Rebecca , Shi Sherry , Adsul Shashi
Published: August 2019

Background

Little is known about long-term real-world effectiveness of vedolizumab versus infliximab in biologic-naive patients with inflammatory bowel disease (IBD).

Methods

Biologic-naive IBD patients who received vedolizumab or infliximab in the US Explorys Universe database (May 2014–September 2018) were weighted using Entropy-balancing.

Results

Persistence rates were higher for vedolizumab (N = 542) versus infliximab (N = 1,179) cohort at 12 (84.5% vs 77.5%; P = 0.0061) and 24 (77.6% vs 64.6%; P = 0.0005) months post-maintenance therapy. Healthcare resource utilization composite end point rates were lower in vedolizumab versus infliximab cohort at 12 (36.2% vs 48.2%; P < 0.0001) and 24 (46.9% vs 59.9%; P < 0.0001) months post-treatment initiation.

Conclusions

Biologic-naive IBD patients who received vedolizumab had better long-term real-world effectiveness measures versus infliximab patients.
Impact of trainee involvement in esophagectomy on clinical outcomes: a narrative systematic review of the literature
Authors: Prasad P , Navidi M , Immanuel A , Griffin OBE S M , Phillips A W
Published: August 2019

Changes in the structure of surgical training have affected trainees’ operative experience. Performing an esophagectomy is being increasingly viewed as a complex technical skill attained after completion of the routine training pathway. This systematic review aimed to identify all studies analyzing the impact of trainee involvement in esophagectomy on clinical outcomes. A search of the major reference databases (Cochrane Library, MEDLINE, EMBASE) was performed with no time limits up to the date of the search (November 2017). Results were screened in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and study quality assessed using the MINORS (Methodological Index for Non-Randomized Studies) criteria. Four studies that included a total of 42 trainees and 16 consultants were identified, which assessed trainee involvement in open esophagogastric resectional surgery. A total of 1109 patients underwent upper gastrointestinal procedures, of whom 904 patients underwent an esophagectomy. Preoperative characteristics, histology, neoadjuvant treatment, and overall length of hospital stay were comparable between groups. One study found higher rates of anastomotic leaks in procedures primarily performed by trainees as compared to consultants (P < 0.01)—this did not affect overall morbidity or survival; however, overall anastomotic leak rates from the published data were 10.4% (trainee) versus 6.3% (trainer) (P = 0.10). A meta-analysis could not be performed due to the heterogeneity of data. The median MINORS score for the included studies was 13 (range 11–15). This study demonstrates that training can be achieved with excellent results in high-volume centers. This has important implications on the consent process and training delivered, as patients wish to be aware of the risks involved with surgery and can be reassured that appropriately supervised trainee involvement will not adversely affect outcomes.
We need to talk about coursebooks
Authors: Jordan Geoff , Gray Humphrey
Published: August 2019

General English coursebooks have dominated classroom-based ELT for 40 years. Their legitimacy seems unchallengeable; we can hardly remember a time when things were different, or imagine a time when coursebooks will not be used. And yet, coursebooks make assumptions about language learning that are contradicted by robust SLA research findings; they give teachers and students little say in decisions affecting course content and delivery; and they are influenced by commercial interests which some blame for the increasing commodification of education. This article reviews the case against coursebooks and briefly presents three alternative approaches to ELT. We argue that these alternatives have not been given the exposure they deserve in journals, conferences, and teacher training programmes, and that it is time to engage in more open, critical discussion about the strengths and weaknesses of the ubiquitous coursebook.
Simulating the entire natural course of HIV infection by extending the basic viral dynamics equations to include declining viral clearance
Authors: Petravic Janka , Wilson David P
Published: August 2019

The basic model of viral dynamics is a relatively simple set of equations describing the most essential features of the host–pathogen interactions. Coupled with data, it has been used extensively and successfully to reproduce and explain the features of the early acute phase of HIV infection and the effects of antiretroviral treatment, as well as to estimate the lifespan of infected cells, viral growth and clearance rates and predict early outcomes under different circumstances. However, it cannot reproduce the entire natural course of untreated HIV infection consistently with constant parameters. Here we show that it is possible to qualitatively reproduce the whole course of untreated HIV infection within the general framework of the basic model by assuming progressively declining viral clearance coupled with viral load. We discuss the interpretation of this model as proof-of-concept that may inspire further research into the role of viral clearance in HIV infection.
Marine science within a net-zero emission statutory framework
Authors: Turrell W R
Published: August 2019

Inspired by the growing cries from young climate crisis activists, and noting that net-zero emission legislation is growing in frequency across Europe and globally, this paper briefly discuses some ways in which marine science might respond. Marine science can provide governments support and advice for emission-reducing policies and actions, as well as tackling our own emissions. Supporting government actions will require new and innovative science. While implementing this science, as a community, we can lead by example in bringing about change in the way professionals do business and hence reducing business’s overall carbon footprint. After all, if environmental science cannot change, why should the rest of society?