IMPLEMENTATION OF GEOGEBRA COURSEWARE IN TEACHING THE CONCEPT OF MATHEMATICAL FUNCTION by Y. V. Gromova, I. S. Safuanov

“…The paper recommends a series of particular exercises, based on the APOS theory (Action – Process – Object – Scheme), along with the Geogebra courseware to help students master their conceptual understanding of mathematical function, and its operational options in various mathematical contexts (e.g. calculating the roots, estimating the limits and derivatives, changing the parameters, solving practical problems, etc). …”
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Robust identification for input non‐uniformly sampled Wiener model by the expectation‐maximisation algorithm by Qibing Jin, Zeyu Wang

“…The Differential Evolution algorithm is used to calculate the intractable part of the Q‐function. The convergence analysis of the proposed algorithm is given. …”
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Estimation of parameters for 3D geomechanical modeling from triaxial test results by Artem Kukhtinskii

“…A Python script is developed to automate the calculation of elastic modulus and Poisson's ratio, overcoming subjectivity in selecting the linear portion of stress-strain curves. …”
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Soil nematodes in the field and fallow - density and diversity by Krassimira Ilieva-Makulec, Renata Franczak, Grzegorz Makulec

“…Shannon-Weaver diversity index, Sørensen’s index of similarity and Maturity index were also calculated. The results show that the nematode community in the soil of arable field differed from that on the fallow in respect of density and trophic structure. …”
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Dynamic Contact Analysis of Torus-involute Gear by Fang Meijuan, Liu Lei

“…Taking the torus-involute gear as study object,according to the theory of gear meshing and the gear hobbing process,the tooth surface equations of torus-involute gears with convex and concave teeth are derived by using the tooth surface equation of counterpart rack.According to the mathematical conditions of neither undercutting nor tooth pointing,based on MATLAB,the Graphical User Interface which contains geometric parameter designs of torus-involute gear is developed.In the light of the tooth surface equations of torus-involute gear,the three-dimensional coordinates of torus-involute gear are calculated which can be used to develop the3-D solid models.The Hypermesh is used to mesh the 3-D models of torus-involute gear.Based on the nonlinear contact algorithm,the finite element models of convex and concave torus-involute gears meshing are established which can be used to implement the dynamic contact analysis in ABAQUS.The results reveal that the width of torus-involute gears is limited by gear undercutting or tooth pointing and the maximum contact stress will be steady after hobbing for a while.The contact stress is small when just a pair of gear teeth are meshing,while the contact stress is large when two pairs of gear teeth are meshing.…”
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The Effect of the Method of Preparation on the Textural, Acidic and Catalytic Properties of Chromia–Alumina Catalysts by Th. El-Nabarawy, L.B. Khalil, A. M. Youssef

“…The chemisorption of pyridine at 400 K was measured and the surface acidities calculated. The conversion of 2-propanol and cracking of cumene were investigated using the pulse microcatalytic technique. …”
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Percutaneous cystolitholapaxy in reconstructed bladder through the bowel segment by Razan Khalid Almesned, Abdulrahman Binjawhar, Waleed Altaweel, Mohammed Alomar

“…Introduction: Calculous formation is a well-known complication of lower urinary tract reconstruction using an intestinal segment. …”
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Subtractive pixel adjacency matrix based features for steganalysis of spatial color images by Tao HAN, Xi CHEN, Yue-fei ZHU

“…Afterwards, the transition probability mat ices of the subtractive pixel adjacency matrices among the color channels were calculated, where four horizontal and vertical directions, and four diagonal and anti-diagonal directions are separately merged. …”
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Hydraulic and Mechanical Relationship of Individual Fracture in Rock under Compression and Shearing: Theoretical Study by Zhiqiang Zhou, Yu Zhao, Chaolin Wang

“…Then, a formulation for calculating fracture permeability during shearing and compression processes is developed. …”
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Kinematics Modeling and Simulation of a Self-propelled Wrapping Packaging Robot by Chen Yu, Shi Yalei, Hu Yakai, Wang Liangwen, Liu Xuling, Jing Xiaodi

“…A simulation analysis system is developed based on the mathematical model of the mobile robot arm and the model of winding typical objects. The calculation and simulation results show that the wrap-around packaging robot can complete the wrapping work of packaging film and meet the design requirements. …”
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Tooth Surface Design and Finite Element Analysis of Circular-arc Tooth Curvilinear Cylindrical Gear by Gao Xiaowei, Jia Jie, Yan Chang, Song Xuding

“…On the basis of the meshing theory of circular-arc tooth curvilinear cylinder gear,the corresponding design method and cutting theory are studied,and the tooth surface forming principle is analyzed.By using a double-sided cutter generating method and taking the cutting cone tooth surface which formed by cutter blade rotating as the imaginary tooth surface,the meshing process of the circular-arc tooth curvilinear cylindrical gear is simulated,the tooth surface equation is derived,the tooth surface numerical simulation is carried out and the visualization is realized.Then,the finite element mesh model is imported into ABAQUS software to carry out the finite element analysis,the contrastive analysis between the finite element analysis result and Hertz contact theory is carried out,and the result shows that built finite element model is reasonable.Through the comparison between the analysis results and the cylindrical gear with the same size,the result shows that the contact strength of circular-arc tooth curvilinear cylindrical gear is better than spur involute cylindrical gear.Beside,through the comparison analysis of the three groups size calculation examples of cutter radius,the relation between the cutter radius size and stress size is obtained.…”
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Particle Swarm Algorithms to Solve Engineering Problems: A Comparison of Performance by Giordano Tomassetti, Leticia Cagnina

“…In fact, in real-world problems, each objective evaluation is frequently obtained by time-expensive numerical calculations. On the other hand, gradient-based algorithms are able to identify optima with a reduced number of objective evaluations, but they have limited exploration capabilities of the search domain and some restrictions when dealing with noncontinuous functions. …”
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Nonlocal Electron-Phonon Interaction as a Source of Dynamic Charge Stripes in the Cuprates by Claus Falter, Thomas Bauer

“…We calculate for La2CuO4 the phonon-induced redistribution of the electronic charge density in the insulating, the underdoped pseudogap, and the more conventional metallic state as obtained for optimal and overdoping, respectively. …”
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Determination of System Dimensionality from Observing Near-Normal Distributions by Shahid Razzaq, Shehzad Khalid

“…We also show that the dimensionality of the latent model, that is, the number of hidden variables in a system, can be calculated from the observed distribution. We call the new distribution “Tanazur” and show through experiments that it is at least observed in one real world scenario, that of the motion of particles in an ideal gas. …”
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A Novel Contextual Information Recommendation Model and Its Application in e-Commerce Customer Satisfaction Management by Feipeng Guo, Qibei Lu

“…Then, the sensitive contexts extracted from user are introduced into the process of collaborative filtering recommendation. The model calculates similarity among user interests. Finally, a novel collaborative filtering algorithm integrating with context and user similarity is designed. …”
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The Evidence of Cooperative Binding of a Ligand to G4 DNA by A. G. Kudrev

“…In the present communication, the hard + soft modelling approach to calculate intrinsic constants of a ligand binding with short DNA molecule, particularly such as G4 DNA, has been proposed. …”
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Observer-Based Adaptive Fuzzy Predefined Performance Control of a Class of Nonlinear Pure-Feedback Systems with Input Delay by Xin Li, Qiang Zhang, Dakuo He

“…Moreover, dynamic surface control and Nussbaum functions are applied to overcome the calculation explosion caused by repeated differentiations and unknown control direction, respectively. …”
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Detection method of LDoS attack based on ACK serial number step-length by Zhijun WU, Qingbo PAN, Meng YUE

“…Low-rate denial of service (LDoS) attack is a potential security threat to big data centers and cloud computing platforms because of its strong concealment.Based on the analysis of network traffic during the LDoS attack,statistical analysis was given of ACK packets returned by the data receiver to the sender,and result reveals the sequence number step had the characteristics of volatility during the LDoS attack.The permutation entropy method was adopted to extract the characteristics of volatility.Hence,an LDoS attack detection method based on ACK serial number step permutation entropy was proposed.The serial number was sampled and the step length was calculated through collecting the ACK packets that received at the end of sender.Then,the permutation entropy algorithm with strong time-sensitive was used to detect the mutation step time,and achieve the goal of detecting LDoS attack.A test-bed was designed and built in the actual network environment for the purpose of verifying the proposed approach performance.Experimental results show that the proposed approach has better detection performance and has achieved better detection effect.…”
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QoE utility function-based cross-layer resource allocation in multi-user MIMO-OFDM systems by Da-ming WANG, Song CHEN, Wei-jia CUI, Qiang WANG

“…Resource allocation problem was investigated for downlink multi-user MIMO-OFDM systems.A QoE (quality of experience) utility function was given according to the characteristics of real-time (RT) and non real-time (NRT) ser-vices,and then a RT ＆amp; NRT QoE utility function-based cross-layer resource allocation algorithm was proposed.The al-gorithm firstly used the designed utility function to calculate the delta QoE,which was offered by users got resource.Secondly,it classified users according to their delta QoE and then allocated time-frequency blocks.Thirdly,it optimized the power allocation result by implementing pseudo water flooding power allocation.Simulation results show that com-pared with the existing algorithm,the proposed algorithm is better in the user average QoE,average packet delay to real time services,average packet lost rate to non real time services as well as sum throughput of system.…”
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Environmental and Socio-Political Security Risks Correlation in Mountainous Areas by Humbatov Fuad

“…In [5], the author introduced a new concept - “Climate Conflict Vulnerability Index” (CCVİ) as a unique metric for assessing the relationship between climate change and socio-political risks. Calculated using a special formula, CCVİ determines the degree of predisposition or inclination of any country, including mountainous ones, to the negative impact of climate conflicts as direct and indirect consequences of global climate change. …”
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