Engineering Commons^™

Pshev Cold Start Emission Simulation Based On Electric Heated Catalyst Pre-Heating, Deng Tao, Haoyuan Yu, Zhifei Li, Haixin Tan

Journal of System Simulation

Abstract: In order to reduce the emissions of the plug-in series hybrid electric vehicle (PSHEV) during the cold start phase, a vehicle model on PSHEV is established and a dynamic model of electrically heated catalyst system (EHCS) based on optimization and control strategy of engine start-stop is built. The PSHEV energy management control strategy based on EHCS preheating is proposed. The influence of different pre-heating power on EHCS temperature is simulated. By comparing SOC value of the control strategy with the original control strategy; and comparative analysis of cold start emissions of three elements catalyst under three strategies of pre-heating, …

Knee Joint Biomechanics In Transtibial Amputees In Gait, Cycling, And Elliptical Training, Greg Orekhov, A. Matt Robinson, Scott J. Hazelwood, Stephen M. Klisch

Biomedical Engineering

Transtibial amputees may experience decreased quality of life due to increased risk of knee joint osteoarthritis (OA). No prior studies have compared knee joint biomechanics for the same group of transtibial amputees in gait, cycling, and elliptical training. Thus, the goal of this study was to identify preferred exercises for transtibial amputees in the context of reducing risk of knee OA. The hypotheses were: 1) knee biomechanics would differ due to participant status (amputee, control), exercise, and leg type (intact, residual) and 2) gait kinematic parameters would differ due to participant status and leg type. Ten unilateral transtibial amputee and …

Design Of Nonsmooth And Inversed Control Algorithm For Nonlinear Structural Vibration Control, Jianhui Wang, Wang Qing, Kemao Ma, Xiaofang Huang

Journal of System Simulation

Abstract: Considering the vibration effects of seismic waves on building with nonlinear structures, a nonsmooth and inversed control algorithm is used to suppress the vibration. It overcomes the faults of ignoring nonlinear influence in traditional approximate linearization control method and suppresses the influence of seismic waves effectively. According to Lyapunov stable theory and finite-time stability theory, the proposed control method to realize the stability of the nonlinear structural vibration is demonstrated. In the realization of the control method, the extended state observer is used to estimate the unknown disturbances. The numerical simulation is conducted for an eight-story building influenced …

Simulation Platform For Invulnerability Of Industrial Wireless Sensor Networks, Xiuwen Fu, Yongsheng Yang

Journal of System Simulation

Abstract: Existing simulation platforms for industrial wireless sensor networks (IWSNs) mainly focus on the general scenario and fail to take into consideration the impacts of interference brought by external environments and emergencies on network performance, thus failing to evaluate the network invulnerability. For given the environment-impacted and event-driven features of IWSNs, the connections between network invulnerability and deployment environment are built. On this basis, a simulation platform for invulnerability of IWSNs is proposed by introducing deployment environment component and event creator. Experiments show that the platform is capable of evaluating the invulnerability of IWSNs.

Surgery Simulation Of Internal Fixation For Compression Fractures, Xie Cui, Junmei Geng, Li Jian, Junyu Dong

Journal of System Simulation

Abstract: Virtual surgery simulation provides new means for medical surgery training with realism and immersion. A virtual surgery simulation of internal fixation for compression fractures is designed and implemented. By constructing 3D surgical scene, making deformation animation, adopting multi-level colliders combination and switching method for collision detection, and designing a multi-factors force feedback model to compute the tactile force and mapping the values to the different levels of vibration intensity of the HTC handle, combining with voice guidance and UI visual feedback, a visual, audible and tactile multi-channel surgical experience can be obtained. The system provides a guiding training module …

A Just-In-Time Learning Soft Sensing Modeling Method Based On Bayesian Gaussian Mixture Model, Qi Cheng, Weili Xiong

Journal of System Simulation

Abstract: For some time-varying industrial processes with non-Gaussian properties, the model established by the general soft-sensing method is difficult to meet the accuracy requirement. To solve the above problems effectively, a JITL soft sensor modeling method (BGMM) is proposed based on Bayesian Gaussian Mixture Model. For the given training sample set, the number of components of the Gaussian mixture model is optimized by Bayesian Information Criterion (BIC); For new test samples, Gaussian Process Regression (GPR) model is established by using the BGMM similarity criterion for the training samples to find out the most similar set;The model is used to predict …

Hpc-Based Virtual Flight Test Method For Multidisciplinary Multiphysical Field Coupling, Tie Ming, Yu Ying, Zhang Xing, Jianlin Wang

Journal of System Simulation

Abstract: Multidisciplinary simulation based on virtual flight system testbed (FST) will become an alternative way for the overall performance validation of near space hypersonic vehicles (HSV). The complexity of multi-physical field coupled modeling and simulation challenges the accuracy and efficiency of virtual experiment. Therefore, a multi-physical-field coupling simulation model is established. The architecture of HPC-FST is explicitly expounded for large-scale parallel multidisciplinary virtual flight tests and multi-physics coupling simulation of whole vehicle. Moreover, an integration algorithm is developed for heterogeneous CAE models in collaborative simulation. A HPC based parallel virtual flight test method with a task-level and algorithm-level hybrid large-scale …

An Investigation Of The Chemistry, Thermodynamics And Catalytic Activity Of Molybdenum Carbides, Shanti Kiran Nayak

Chemical and Biological Engineering ETDs

These studies investigate the chemistry and stability of molybdenum carbides as an electrocatalyst. Due to their unique electronic properties, molybdenum carbides are purposed as electrocatalysts for reaction systems such as hydrogen evolution reaction, bifunctional water splitting and CO oxidation.

In this study, various synthesis processes were utilized to produce different types of molybdenum carbide with varying properties of particle size, surface area and excess carbon. The samples characterized by XRD accompanied by Whole Profile Fitting, Electron Microscopy, Gas Adsorption (surface area) and XPS.

These synthesis processes were refined using fundamental thermodynamic analyses. These analyses highlight regions of stability of different …

Extreme Image Compression With Deep Learning Autoencoder, Licheng Xiao

Computer Science and Engineering Master's Theses

Image compression can save billions of dollars in the industry by reducing the bits needed to store and transfer an image without significantly losing visual quality. Traditional image compression methods use transform, quantization, predictive coding and entropy coding to tackle the problem, represented by international standards like JPEG (joint photographic experts group), JPEG 2000, BPG (better portable graphics), and HEIC (high efficiency image file format). Recently, there are deep learning based image compression approaches that achieved similar or better performance compared with traditional methods, represented by autoencoder, GAN (generative adversarial networks) and super-resolution based approaches.

In this paper, we built …

Status And Development Analysis Of Hardware-In-Loop Simulation Technologies For The Aircraft, Ruisong Huang, Haifeng Li, Liu Jin, Wenhua Kong

Journal of System Simulation

Abstract: Hardware-in-the-loop (HWIL) simulation technologies for complex engineering systems such as Aircraft has become an indispensable and important simulation method. With the emergence of new technologies, and the development of new concepts and requirements of Aircraft, HWIL simulation capability of Aircraft is constantly making breakthroughs. The current status of HWIL simulation technologies for Aircraft is analyzed, as well as the proposals to the development of HWIL simulation technology.

Using Brookfield's Critical Incident Questionnaires To Improve Collaboration In Course Modules, Albena Yordanova, Elizabeth Tofte

ASEE Best Practice Series Presentations

No abstract provided.

Bridging The Gaps In Elementary Life Science Lessons, Kaitlin Cook

Honors Program Theses and Projects

The United States is experiencing a rise in science, technology, engineering and mathematics (STEM) careers while facing a shortage of STEM workers. This could partly be due to a decline in the amount of time allowed for science in elementary schools or possibly because many life science lessons in elementary school lack originality and may not stimulate an interest in science. Lack of captivating STEM education prior to college may be contributing to the decline of students graduating with STEM based degrees. My thesis focuses on getting out of the routine of using monotonous life science lesson plans. I identify …

Human Re-Identification Based On Part Segmentation, Jiang Hua, Zhang Liang

Journal of System Simulation

Abstract: Human re-identification is a difficult problem to solve in process of video analysis of non-overlapping multi-camera surveillance system. A new algorithm of human re-identification is proposed on the basis of human part segmentation. Based on the depth of bone points to achieve the human body segmentation, the optimal key frame is selected by using the scoring strategy for all parts of the same human multi-frame image segmentation; the different weights for the global color feature and the HOG feature are assigned; all the characteristics to establish a human target model are combined; and the EMD (Earth Mover’s …

Osgearth Stereoscopic Vision Generation Method For Hmd-Based Virtual Reality, Liheng Tan, Ma Qiang, Bingchuan Jiang, Li Feng

Journal of System Simulation

Abstract: The technology of immersive virtual reality based on helmet mounted display (HMD) has become a focus of study, however, its visual content is mainly produced through commercial game engines. OsgEarth is an open-source, state-of-the-art and widely used digital earth simulation system. Based on this, we studies the stereoscopic vision generation method for global virtual terrain environment, mainly focusing on: stereoscopic vision theory; construction of global high-precision virtual geographical environment; calculation of binocular view frustrum; system integration. The proposed method is verified under the hardware conditions of PC and HTC VIVE, which can generate stereo images of the global virtual …

Design And Implementation Of Interactive Ar System For Campus Roaming, Shengwei Qin, Li Zhong, Jinfeng Li, Zihao Chen, Jingqian Ding, Wanshun Liu

Journal of System Simulation

Abstract: There are many kinds of navigation applications in universities recently. These applications have obvious shortcomings, which only indicate the outdoor locations without detail information; even some places cannot be found in the map; and it takes a lot of time to design a system. Meanwhile the system cannot achieve real-time interaction effect in virtual ramble. An interactive campus roaming augmented reality (AR) system is designed combining with GPS module for locating outside the campus and utilizing deep learning technology to achieve locating the inside buildings of campus. Simultaneously AR technology will improve interactivity of the system. The experiment …

Pulse Signal Detection Based On Dual Extended Duffing Oscillators, Wenmao Luo

Journal of System Simulation

Abstract: Because the chaotic oscillator can detect signal under lower SNR than the usual signal detection methods, it has been widely studied. In order to extend the application range of the existing chaotic oscillator to aperiodic pulse signal detection, a detection method based on dual Duffing oscillator is proposed. The method uses the difference between the state variables of two generalized time scale Duffing oscillators to detect signal. By selecting the system parameters rationally, the method can detect aperiodic square pulse while the SNR is as low as -30 dB, and detect signals at lower SNR than existing methods. …

Visualization Analysis Method Of Passenger Hotspot Based On Fast Density Clustering, Zihe Huang, Shangbing Gao, Zhigeng Pan, Hui Hao, Qiyu Liao, Fengfeng Zhao

Journal of System Simulation

Abstract: With the development of urbanized transportation, the perceptual computing plays an important role in smart cities. Aiming at the problem that the traditional density clustering algorithm cannot adapt to massive taxi GPS trajectory data and visualization, the BCS-DBSCAN (Big-Data Cluster Center Statistics Density-Based Spatial Clustering of Applications with Noise) clustering algorithm is proposed. The algorithm can segment and parallelize the trajectory data, extract the maximum density cluster, and adapt the result to the visualization model. The experimental results show that compared with other popular methods, this method has significant advantages in extracting clustering speed, accuracy and visualization of urban …

The Simulation Of Ac Servo Network Control System, Wang Lin, Chongquan Zhong

Journal of System Simulation

Abstract: The networking trend of AC servo system is becoming more and more remarkable. The research on permanent magnet synchronous motor(PMSM) mainly focuses on the continuous improvement of control strategy. It is rarely combined with solving real network delay and packet loss problems. The vector control strategy of PMSM is studied. In view of the delay and packet loss in the network environment, the mathematical model of network control system (NCS) is derived, and a simulation model based on TrueTime and Simulink is established to simulate the delay and packet loss phenomenon in the network transmission. The results show that …

Control Optimization Of Hybrid System With Hybrid Power Based On Dp Algorithm, Deng Tao, Haoyuan Yu, Bin Xu

Journal of System Simulation

Abstract: Aiming at the complexity and diversity of energy management for HEV(hybrid electric vehicle) with hybrid power, taking the State of Charge of power battery and ultracapacitor as state variable, the torque distribution ratio between engine and motor, and the power distribution ratio between power battery and ultracapacitor as control variables, the fuel economy and emission performance as objective function, the Dynamic Programming (DP) control strategy for HEV with hybrid power is proposed. The working rules of the engine, motor, battery and ultracapacitor, are extracted from the results, and the rules of engine and motor and the fuzzy control …

Research On Radar Signal Sorting Based On Ensemble Deep Learning, Weidong Jin, Chunli Chen

Journal of System Simulation

Abstract: In view of the fact it is difficult to extract the appropriate features quickly and present signal sorting method’s accuracy is low, a signal sorting method based on ensemble deep learning model is proposed. This method stacks different types of deep belief network for radar emitter signal feature learning to improve algorithm. After learning the characteristics of the radar emitter signals deeply, the posterior probability of each model is linearly integrated and learned and the final classification results are determined by the decision layer to further improve the signal recognition rate. The method is used to separate different …

Nonlinear Sliding Mode Control For Robotic Manipulator Based On Disturbance Observer, Gensuo Mi, Huaqi Liang

Journal of System Simulation

Abstract: A nonlinear sliding mode control strategy of manipulator based on disturbance observer is designed for the characteristics of the manipulator which is sensitive to internal parameter disturbance and the external disturbance in the position tracking. According to the system dynamics model and Lyapunov stability theory, the uncertainties and external disturbances of the system are observed by disturbance observer. At the same time, the nonlinear sliding mode controller is designed and the Lyapunov function is constructed to verify the stability of the system. On this basis, the system control law and the sliding mode control law are designed to compensate …

A Generation Method Of Amf General Files For Heterogeneous Nurbs Volume Parametric Model, Chen Long, Wenyu Han, Xu Gang

Journal of System Simulation

Abstract: Aiming at the three-dimensional printing technology of heterogeneous NURBS (Heterogeneous Non-Uniform Rational B-spline, HNURBS) volume parametrization model, a method of generatingthe AMF (Additive Manufacturing File Format) of the three dimensional printing general file is proposed. For the continuous visual expression of material information, theHNURBS volume parametric model is constructed with the control points containing material information which is represented with gray value.According to the subdivision of the NURBS volume parametric model, the HNURBS volume parametric model is subdivided into Isoparametric mesh element. In order to get the triangular mesh for the generation of the AMF files, each …

The Optimized Synthesis Of Copper Nanowire For High-Quality And Fabrication Of Core-Shell Nanowire, Suhyun Lee

Dissertations and Theses

Flexible electronics are the promising technology for prospective application in foldable phones. Currently, indium tin oxide (ITO) has been widely used for electronic devices including flat-panel display. However, it is brittle and expensive. Metal nanowires are considered as alternative materials. Among various metal nanowires, copper nanowires are attractive because of its high electrical conductivity, better flexibility, and low cost compared with ITO. However, copper nanowires are very prone to oxidize, which causes subsequent degradation of electrical conductivity. Due to this oxidation issue, core-shell structure nanowires, which are formed silver shell having high conductivity and low resistivity on the surfaces of …

Analysis Of Transition Processes In Power Systems With Hydroenergetic Istallations, O.Y. Nurmatov, S. K. Matkarimov

Technical science and innovation

This article is presented an overview of hydro mechanical and electromechanical processes. Little attention was paid to the study of these two areas at the same time. The two directions above are the results of a simultaneous study. A joint study of these components of a single process received little attention. In conclusion, conclusions are drawn on the effect of AER (automatic excitation regulator) on the damped operational parameters and ensuring the stable operation of hydropower plants. The results can be used in the reconstruction of existing and designing new pumping stations, so transients are considered for a certain range …

The Corrosion Stability Increase Of Adhering Coating Under The Process Of Electrochemical Mechanism, S. M. Turabdzhanov, M. S. Lee, U. A. Ziyamukhamedova, G. B. Miradullaeva

Technical science and innovation

The article discusses the development of organomineral materials for the protection of metal parts of technological machines and structures operating mainly under the influence of an electrochemical environment. A technology has been developed for producing modified organomineral materials for anticorrosive coatings using micro- and nanosized particles of layered silicates (mineral fillers). The mechanism of the formation of nanocomposites using layered silicates and organic materials for anti-corrosion coatings formed by the activation-heliotechnological method is investigated. Using thermomechanical, physical and physico-chemical methods for studying the structure and properties of the materials obtained. Among these methods are: IR spectral analysis, scanning electron microscopy, …

Certification Of Vegetable Oils And Quality Control In The Technological Process Of Production, Ch.A. Bekmurotov

Technical science and innovation

The article reviewed the certification and quality control of the technological process for the production of vegetable oil. There is a procedure for packaging, quality control of products, determination of quality indicators and quality control of finished products. The procedure for using refined cottonseed oil and its varieties, the requirements for placement and storage of vegetable oils, as specified in the regulatory documents, the quality control of vegetable oils and other solutions for cottonseed oil are provided. The gas analyzer shows a solution for measuring the amount of solution by painting the tubes of a mixture of gas and air …

Methods For Researching The Localization And Delocalization Of Carriers In Yba2cu3o6+X Films, Q.H. Bobomurodov, J.Kh. Razakov, S.Q. Bobomurodov, R.A. Shokirov

Technical science and innovation

The results of the study of optical absorption of metal films YBa2Cu3O6+x when passing through the film direct current to 100 mA are presented. Analysis of the data indicates that the relationship between absorption and current arises due to the possibility of filling the localization areas with carriers in the current mode (or vice versa, due to the emission of localized carriers to the mobility level). Fdor films with substantially nonlinear voltammper characteristic, a strong effect of current on the value of interzone absorption was found. It has been experimentally established that the EO-effect occurs at interzone transitions only in …

Study On Simulation Technology Of Bi-/Multistatic Sar Radio Echo, Liu Jin, Zhe Liu, Ni Hong, Qingchang Tao

Journal of System Simulation

Abstract: A real-time bi-/multistatic synthetic aperture radar (SAR) radio frequency signal simulation method for three-dimensional scene target is proposed. This method divides scene map with 5*5m resolution and presets ackscattering-coefficient. According to the flight path and geometrical model, the key parameters such as the range between SAR and target and the weighting coefficient of the antenna pattern can be calculated. Then, the real-time simulation of bi-/multistatic SAR echo signal is realized in complex scenes by utilizing fast time-domain convolution. The validity of the method is proved by simulation.

Joint Resource Partitioning And Offloading Analysis In Heterogeneous Ultra-Dense Networks, Zhen Yan, Jiangpan Shi, Qiaoshou Liu

Journal of System Simulation

Abstract: For the problem of load balancing between macro base station and small base station in heterogeneous ultra-dense networks, a general offloading framework is proposed based on the distance between users and the nearest base station. By partitioning network spectrum resource and using stochastic geometry, the expression of coverage probability and average ergodic rate of users in the fixed region and the random region are deduced on the basis of guaranteeing the quality of service of the macro users offloaded. The simulation results show that the combination of resource partitioning and offloading effectively improves the coverage probability and average ergodic …

A Review Of Modeling Human Travel And Social Contacts For Public Health Management, Duan Wei, Guo Gang, Bin Chen, Duan Hong

Journal of System Simulation

Abstract: It is significant to understand the patterns of human mobility and social contacts for epidemic prevention and control. This paper analyses the regularities and the statistical properties of human behaviors at the perspective of human dynamics. Various models of human mobility and social contacts are comparatively investigated , including Brownian movement, random walks, spatial network, Motifs, bipartite graph model, gravity models, contact rate, the distribution of daily contact number, social networks, etc. The models of human behavior changes in the course of epidemic outbreak are also analyzed. The challenges of modeling human mobility and social contacts are discussed …