bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Analysis of Discharging Speed of a Horizontally Rotating Drum with Internal Baffles by Using DEM Simulation
Authors: Tian Zhongke , Yu Haiyong , Han Congcong 
Published: April 2020

Abstract
Although the concept seems simple, the motion of bulk materials in a rotating drum is rather complex. In this paper, the process of throwing the evenly mixed materials out of a horizontally rotating mixing tank with internal baffles was concerned. The reasonable rotary speeds for the discharging process as well as the ideal process durations were quantitatively determined by running simulations based on the Discrete Element Method (DEM) software PFC3D. The particle-counting codes, developed in PFC3D built-in programming language FISH, took important roles in evaluating the corresponding effects of different process parameters, which overcame the uncertainty of usual qualitative analysis of simulation results.
Implicit Community Discovery Based on Microblog Theme Homogeneity
Authors: Sun Zefen , Du Yajun , Chen Xiaoliang , Wang Chunjia 
Published: April 2020

Abstract
With the rapid development of various social platforms, social networks have accumulated more and more data. These huge and complex data contain valuable information in many fields. It is of far-reaching significance to conduct statistical analysis of these data and dig out valuable information and apply it in real life. Based on the homogeneity of social networks, our paper proposes a framework of discovery algorithms based on the homogeneity of microblogs to realize the theme community discovery of microblog social networks. Firstly, the data set is preprocessed, the invalid data is removed and classified by microblog users. Secondly, the LDA model is used to extract the topic of microblog user blogs to describe the characteristics of microblog users. Thirdly, two users are calculated based on the theme interest. The homogeneity measure between them is used to represent the relationship of social networks. Finally, the community of the implicit social network is realized through unsupervised algorithms to build communities with the same interest as the theme. In order to verify the validity of our proposed algorithm framework, this paper uses data sets from microblog network to conduct experiments. The experimental results show that the algorithm effectively combines the homogeneity measure of the network and has achieved very good results in the implicit community discovery.
The Application of the Integrated Machine Learning Model in the Financial Crisis of Imbalanced Samples
Authors: Lu Zhang , Liu Jiapeng , Jiang Minqi 
Published: April 2020

Abstract
In this paper, the financial crisis of the enterprise in the t-period is predicted by the financial index data of the non-financial industry A-share enterprise in the main board market of the Shanghai Stock Exchange in the t-3 period. Then we use the integrated machine learning models to select the financial crisis enterprises, and the problem of failure of classifiers in unbalanced samples is solved through bagging and sampling techniques. The highest probability of correctly selecting enterprises with financial crisis is 92.86%. With the integration of the model, the overall accuracy is improved to 88%. We help the enterprise to complete the forward-looking financial crisis forecast and provide some reference for the business activities and investment activities of the enterprise.
Short-Term Load Forecasting Using Modified Sequence-to-Sequence Deep Learning Framework
Authors: Luo Jun , Zhu Keyu , Wang Xiaojia 
Published: April 2020

Abstract
The future of smart grids promises unprecedented flexibility in energy management. Therefore, it is crucial to accurately predict the energy load demand of individual power grid stations and overall levels. In this paper, a Sequence to Sequence learning method based on long short-term memory neural network (Seq2Seq) forecast model is proposed to predict the load of the community microgrid. In particular, this paper studies the effectiveness of Seq2Seq in community microgrid load forecasting, avoiding overfitting through weight attenuation regularization, and reducing the impact of interference and noise on training data. The proposed method is implemented on the base load data set of multi-user. The results of Seq2Seq were compared with the results of two well-known methods, one is traditional LSTM and the other is Support Vector Machine (SVM) on the same datasets. Experimental results show that compared with SVM and traditional LSTM, Seq2Seq has better learning effect. Finally, we calculate the performance index. When using load data to train and test the model, it was noted that compared with traditional LSTM and SVM, the root mean square error (RMSE) of Seq2Seq was decreased by 44.07% and 64.06%, respectively. Our research offers a decent reference for the application of deep learning in the field of energy management.
A New Fast Computation of a Permanent
Authors: Niu Xuewei , Su Shenghui , Zheng Jianghua 
Published: April 2020

Abstract
Store-zechin is a general algorithm for computing the permanent of a square matrix, and the core ideas of this algorithm are multiplexing, recursion and storage. It means we just calculate once for every sub-items and for the second time, the previous result is substituted into the calculation. The advantage of Store-zechin algorithm is that it can make full use of computer memories and accelerate the calculations. In fact, it needs 2
n-1
(n- 2) + 1 additions and (2
n-1
- 1)n multiplications for computing the permanent of an n ± n matrix by Store-zechin algorithm. In the same situation, Ryser algorithm requires (2
n
- n)(n + 1) – 2 additions and (2
n
- 1) (n – 1) multiplications, R-NW algorithm requires 2
n-1
(n + 1) + n
2 - n -1 additions and 2
n-1

n + n + 2 multiplications. So Store-zechin has n2
n-1
+2
n+1
-n
2-n-3 additions, n2
n-1
-2
n
+1 multiplications less than the Ryser algorithm, and 2
n-1
+2
n
+n
2-n-2 additions, 2n+2 multiplications less than the R-NW algorithm. It can be confirmed that the Store-zechin can indeed calculate a permanent in fewer steps.
A Comparative Study of Moving Target Detection Algorithms
Authors: Wang Yuanyuan , Zhou Xiaolei , Zuo Yuanyuan , Wu Zhuang 
Published: April 2020

Abstract
This paper wants to analyze and compare the mainstream algorithms for moving target detection and lay a foundation for algorithm improvements as well as for such research directions as intelligent transportation system and traffic calculation, this paper selects three target detection algorithms for comparative study: methods of interframe difference, background difference and optical flow. It conducts simulation experiment on traffic surveillance videos with MATLAB programming, selects the threshold for frame difference method suitable for the current video and improves detection accuracy by binaryzation, expansion, corrosion and other processing methods. Interframe difference method compares the effects between the original difference image and grayscale difference image and considers bad difference caused by excessive moving distance. Background difference method compares the effect images after morphological processing, and reduces the impact of noises. The advantages are shown by comparing the original image with the labeled optical flow diagram using the optical flow method. By comparing the recognition effect images and processing time of these three algorithms, it analyzes and concludes the strengths and weaknesses as well as the ranges of application in intelligent transportation system.
A Bearing Fault Diagnosis Method Based on Dictionary Learning and Parameter-Optimized Support Vector Machine
Authors: Yang Jing , Hao Yan , Xu Ting , Yan Huichao , Hu Hongping , Bai Yanping 
Published: April 2020

Abstract
Aiming at the problem of fault diagnosis, a novel method based on dictionary learning and parameter-optimized Support Vector Machine (SVM) was proposed in this paper and applied it to bearing fault diagnosis. Firstly, the collected bearing fault signals are transformed into gray images after data processing. Then, using dictionary learning, the gray images are denoised and output them as signal data. Finally, the SVM multi-classification model obtained by using Grid Search (GS) algorithm to optimize penalty parameter c and kernel function parameter g is used to classify and identify the fault type. This paper is based on data from Case Western Reserve University Bearing Center for experimental verification. The results show that the proposed model can continuously achieve the accuracy of 100% in the process of bearing fault diagnosis in different environments, which proves that the proposed method can accurately and effectively realize the fault diagnosis classification of bearings.
Research on Integrated Scheduling Optimization of Double-trolley Quay Crane and AGV in Automated Terminal
Authors: Chen Jiajuan , Du Wei , Wang Hongxuan , Guo Dong 
Published: April 2020

Abstract
With the upsizing of ships, the operating efficiency of automated container terminals is becoming increasingly important. Based on the operation mode of loading and unloading synchronization, we first established an integrated scheduling optimization model of Double-trolley Quay Crane (QC) and AGV. Secondly, we designed a genetic algorithm embedded in tabu search to improve its local optimization ability. Finally, we conduct an empirical analysis. In the same case size, compared with the traditional genetic algorithm, the genetic algorithm embedded in tabu search has shorter model solving time and lower model optimal solution fitness. The maximum difference of the model solving time and the optimal solution fitness value can reach 165.113% and 7.71%, respectively. The results verify the rationality of the model and the effectiveness of the algorithm.
The Unipotent Condition of Linear Groups Generated by Matrices with Primitive Elements Jorden Blocks of Orders no More Than Eight
Authors: Yang Xin-Song , Pan Guosheng 
Published: April 2020

Abstract
In this paper, the combinatorial properties of free group generators are studied with help of calculation tool, matrix logarithm, and Jacobson radical. The unipotency of matrix groups can be better delineated by these new combinatorial properties, and a new necessary and sufficient unipotent condition of matrix group whose primitive elements Jordan blocks have orders no more than eight, as well as of free groups, will be given. Our result improves the relative theories.
List all Maximal Cliques of an Undirected Graph: A Parallable Algorithm
Authors: Hua Xin , Zhong Maosheng , Liu Qun , Wang Mingwen 
Published: April 2020

Abstract
Listing all the maximal cliques of an undirected graph is considered as a NP-complete problem, even if the existing fastest algorithm for listing all the maximal cliques also needs an exponential time complexity, and these algorithms are not able to be reconstructed into parallel processing algorithms, therefore, which are also unsuited to solve all maximal cliques of a complex undirected graph with a large number of maximal cliques or vertices. This paper aims to develop a parallable algorithm for listing all maximal cliques of the large size complex undirected graph. Firstly we gave some definitions, including adjacent sub-graph, suspended sub-graph and so on, then adopted a partition and recursive strategy to partition equivalently a parent-graph into smaller sub-graphs, so we can get all maximal cliques of parent-graph by recursively listing all maximal cliques of sub-graphs. we have developed a single-thread and a multi-thread program of the algorithm by using Java language. Lastly, we compared the performance of our algorithm in a benchmark data set DIMACS with the existing main algorithms. The results show that our single-thread program is basically equivalent performance with existing algorithms, but the multi-thread program has better performance than the existing algorithms. Because our method is to divide the complex problem into some smaller sub-problems and achieve the solution of the original problem by solving these sub-problems, our algorithm is easy to be implemented by using multi-thread, and also easy to be expanded to the parallel algorithm, which has better feasibility and practicability in solving the large scale complex graph.
Influences of Floating-ring Seal Parameters on Clearance Leakage
Authors: Yuan Zhenwei , Chen Junqi 
Published: April 2020

Abstract
For a type of floating-ring seal widely used in the fields of aeronautics and astronautics, power and energy, and petrochemical engineering, the influences of various parameters on clearance leakage behavior of floating-ring seal are analyzed using numerical method and by means of MATLAB programming. Based on Bulk-flow model, the governing equations of the flow field in the clearance of floating-ring seal are established. The finite difference method and the staggered grid are used to discretize the governing equations. The SIMPLE algorithm is used to solve the discretized equations. The self-locking position of the floating-ring is calculated by analyzing the equilibrium condition of the floating ring, and accordingly the leakage flowrate of the flow field in the clearance of the floating-ring seal are obtained. Finally, the influences of fluid viscosity, inlet swirl, width of floating ring, and relative roughness of floating-ring and rotor surface s on the leakage flowrate are discussed.
A Perceptual Spectrum-Hole Proportional Fairness Scheduling Algorithm Integrated with CR
Authors: Huang Zhongyou , Zhang Yongtang 
Published: April 2020

Abstract
In order to improve the utilization of spectrum resources and solve the problem of unscheduled users in the downlink transmission process in LTE system, we propose a new proportional Fairness scheduling algorithm. The algorithm integrates cognitive radio (CR) technology into proportional Fairness scheduling algorithm, and derives the expression of system throughput under the new algorithm, so that unscheduled users can perceive “spectral-holes” and use the idle spectrum that is not used by the primary user (PU) for data transmission. To achieve maximum resource utilization efficiency. In addition, two secondary user (SU) management schemes for continuing to wait and finding new subcarriers are given, and the delays under the two schemes are calculated. A new decision method is proposed to solve the problem of SU reconstruction. Numerical analysis shows that the new algorithm can ensure the fairness of users, effectively reduce system delay and improve system efficiency.
Upper Bound Estimation of Logarithmic Derivative Norm of Alexandrian Transformation for r-th β-spiral Function
Authors: Duan Min 
Published: April 2020

Abstract
The upper bound of the norm logarithmic derivative of Alexandrian transformation for r-th β-helix function class was estimated based on the principle of dependent function, and the theorem was obtained. The result was the generalization of Schwarz’s derivative and logarithmic derivative in Teichmuller space theory.
Numerical Simulation of Fracture Sequence on Multiple Hydraulic Fracture Propagation in Tight Gas Reservoir
Authors: Zheng Heng , Pu Chunsheng , Sun Chao 
Published: April 2020

Abstract
Hydraulic fracturing with horizontal well is an effective technology for the unconventional resources development, especially for the shale gas, tight gas and oil. Simultaneous fracturing, sequential fracturing and alternating fracturing were the main technologies applied in the horizontal well stimulations. Based on the extended finite element method, the 2D seepage-stress-damage models for simulating fracture propagation of simultaneous fracturing, sequential fracturing and alternating fracturing were proposed to investigate the influence of fracture sequence on fracture propagation and fracture aperture. From the simulations, the sequential fracturing and alternating fracturing can dramatically decrease the limitation on fracture propagation caused by “stress shadow”, the total fracture length increased by 20.6% and 26.1% compared with simultaneous fracturing. The fracture aperture also affected by the fracture sequence. The simulation results demonstrates that the alternating fracturing is an effective method to prevent the fracture width reduction caused by squeezing effect, which can effectively improve the well productivity. These simulations are useful for horizontal wellbore stimulation design to acquire the desired fracture lengths, fracture conductivity and production rates.
An Appearance Inspection Method for Resistance Spot Welding Based on Semantic Segmentation
Authors: Zheng Tianyu , Yang Ye , Zheng Peng , Benz Lukas , Wang Lei 
Published: April 2020

Abstract
Resistance spot welding (RSW) plays an important role in manufacturing. The quality of the welding can be efficiently assessed by its appearance. Image segmentation is an important part of the RSW appearance inspection. However, the classical image segmentation algorithms cannot work very well because of the various RSW appearances. In this study, a novel inspection method is proposed based on semantic segmentation. We choose MobileNetV2 as the backbone for the semantic segmentation. After modification and optimization of the network, our model achieves an accuracy of 89% mean intersection-of-union (mIOU), which is averagely 30% higher than the classical image segmentation algorithms. A classifier further evaluates the quality of the RSW according to some geometric features of the segmented regions, and the classification accuracy is improved by 0.79%. This research is of great importance for the high accuracy quality control of the massive production to reduce the producing cost and improve the efficiency of the RSW pipeline.
Numerical and Experimental Investigation of a Serpentine Inlet Constructed with a Polynomial
Authors: Ge Changjie , Chen Bin , Shang Yinhui , Han Rui 
Published: April 2020

Abstract
The investigation of the serpentine inlet is particularly important due to the high stealth requirements of the next generation unmanned aerial vehicle (UAV). The paper presents a design method of generating a serpentine inlet controlled by a center line which is a polynomial. The serpentine inlet is designed considering the positions of the airborne equipment, the stealth and aerodynamic performances. The study includes numerical simulations based on the Reynolds-averaged Navier-Stokes simulation approach and experiments in wind tunnel. The aerodynamic performances of the serpentine inlet at different inflow Mach numbers, mass flow ratios and angles of attack are obtained. Moreover, the flow structures are studied at several critical conditions and the performance and distortion of the designed serpentine inlet are acceptable without any flow control.
Single Machine Scheduling Problem with Controllable Setup and Job Processing Times and Position-Dependent Workloads
Authors: Luo Chengxin , Zhang Geng 
Published: April 2020

Abstract
This paper concerns with a single-machine scheduling problem in which each job has a setup before being processed, the setup time and the processing time of jobs are controllable by allocating a continuously nonrenewable resource, respectively. This is different from that of [13], in which a job only has a processing time, but without a setup time. We assume that each setup and processing time of jobs has a workload that is both job and position-dependent. In the problem investigated, the total amount of resource for setup and processing times does not exceed an up bound, respectively. The objective is to determine the setup sequence, the job sequence and the resource allocation scheme to minimize makespan. We show that the problem can be solved in polynomial time and present an optimal algorithm.
Analysis on the Influence of Assembly Gap on CFRP Assembly Stress Based on Finite Element Method
Authors: Jiang Qilin , Hou Junming , Fang Xiwu , Wang Hongrui 
Published: April 2020

Abstract
Due to the material properties and forming process of composite laminates, it is difficult to avoid smaller assembly gaps in the assembly process of laminates. In assembly process, liquid gaskets are generally used to compensate the smaller assembly gaps between laminates. Therefore, this paper established the equivalent assembly model of the laminated plate, and used the finite element analysis method to conduct numerical analysis and quantitative research on the mechanical influence of the assembly gap on the laminated plate assembly on the basis of analyzing the typical structure of the wing box. And the results of finite element method are compared with the experiment. This work provides a theoretical support to ensure the assembly quality of composite laminates.
3D-FEA of Implant Thread Depth and Pitch on Interfacial Stresses
Authors: Zhou Yulin , Mao Zhihong , Liu Fan , Wang Ruichao 
Published: April 2020

Abstract
Objective: Using the numerical analysis, the interfacial stresses with various thread depths and pitches implants are evaluated in mandibular bone mass. Methods: Implant parameters considered herein include the thread depths of 0.30, 0.35, 0.40, 0.45, 0.50 and 0.55 mm and the pitches of 0.75, 0.80, 1.0 and 1.25 mm. A simplified bone-implant system is created by Geomagic studio and Solidworks. ANSYS workbench was used to analyze the effects of the stress distribution. Results: The maximum von Mises was exhibited in three position at the implant: the location between implant and abutment, the area between implant and screw and the threaded implant body (connect area between first thread and second thread or second thread and third thread). whereas uneven stress distribution were showed in both cortical bone and trabecular bone under oblique and vertical loading. Conclusions: This study found that the force (magnitude and direction) is the important factor of influence on stress, for biomechanical context, the ratio of the thread depth to the pitch at the implant below 0.55 is more appropriate for controlling the max EQV of implants.
Flight Schedule Strategy of Airport Group
Authors: Lei Li , Zhao Dan , Liu Huaiyuan , Guo Dong 
Published: April 2020

Abstract
Overall consideration of airport group flight schedule optimization can make air traffic flow management more efficient and reasonable. The research features of this paper fully considers the matching of airport, airspace capacity and flow. It took into account the functional positioning of each member airport in the airport group and the airline’s need for “golden hour” during the flight adjustment process and established a seasonal flight time optimization model which targets the minimum flight time adjustment. And taking the Yangtze River Delta Airport Group as an example to carry out a case study.
An Evaluation of Several Pansharpening Methods for Mapping Quasi-circular Vegetation Patches Using GF-2 Imagery
Authors: Liu Qingsheng 
Published: April 2020

Abstract
It is important to identify the quasi-circular vegetation patches (QVPs), which will help understanding the local ecosystem structure, function, evolution, and maintenance, and is beneficial to make a vegetation restoration in the Yellow River Delta, China. The fused imagery with high spectral and spatial resolution are most appropriate data for mapping the QVPs. This study compared the widely used pansharpening approaches such as the modified intensity-hue-saturation, Gram-Schmidt, colour spectral sharpening, and principal component analysis (PC) approach for mapping the QVPs using the tasselled cap brightness and greenness components of one scene of the spring GF-2 imagery with the decision tree classifier. Overall, the PC method produced a slightly good detection result of the QVPs over the other three pansharpening methods. However, the detection accuracy was still low (F measure = 56.8%). It could be improved using multitemporal images and patch splitting techniques in the future.