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2022

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Full-Text Articles in Engineering

A Review On Nanomaterials And Nanohybrids Based Bio-Nanocomposites For Food Packaging, Kalpani Y. Perera, Amit K. Jaiswal, Swarna Jaiswal Dec 2022

A Review On Nanomaterials And Nanohybrids Based Bio-Nanocomposites For Food Packaging, Kalpani Y. Perera, Amit K. Jaiswal, Swarna Jaiswal

Articles

With an increasing demand for a novel, eco-friendly, high-performance packaging material “bio-nanocomposites” has attracted great attention in recent years. The review article aims at to evaluating recent innovation in bio-nanocomposites for food packaging applications. The current trends and research over the last three years of the various bio-nanocomposites including inorganic, organic nanomaterials, and nanohybrids, which are suitable as food packaging materials due to their advanced properties such as high mechanical, thermal, barrier, antimicrobial, and antioxidant are described in detail. In addition, the legislation, migration studies, and SWOT analysis on bio-nanocomposite film have been discussed. It has been observed that the …


Bio-Inspired Micromachined Volumetric Flow Sensor With A Big Dynamic Range For Intravenous Systems, Lansheng Zhang, Yingchen Yang, Georgios A. Bertos, Chang Liu, Huan Hu Dec 2022

Bio-Inspired Micromachined Volumetric Flow Sensor With A Big Dynamic Range For Intravenous Systems, Lansheng Zhang, Yingchen Yang, Georgios A. Bertos, Chang Liu, Huan Hu

Mechanical Engineering Faculty Publications

Real-time monitoring of drug delivery in an intravenous infusion system can prevent injury caused by improper drug doses. As the medicine must be administered into the vein at different rates and doses in different people, an ideal intravenous infusion system requires both a low flow rate and large dynamic range monitoring. In this study, a bio-inspired and micromachined volumetric flow sensor is presented for the biomedical application of an intravenous system. This was realized by integrating two sensing units with different sensitivities on one silicon die to achieve a large dynamic range of the volumetric flow rate. The sensor was …


Overview Of Research And Application On Autonomous Vehicle Oriented Perception System Simulation, Ruoxuan Wang, Jianping Wu, Hui Xu Dec 2022

Overview Of Research And Application On Autonomous Vehicle Oriented Perception System Simulation, Ruoxuan Wang, Jianping Wu, Hui Xu

Journal of System Simulation

Abstract: Following the rapid progress of science and technology, vehicles with autonomous driving or auxiliary driving function enter into vehicle market. However, in the past decade, traffic accidents still occurred frequently, and the safety of these functions become the focus. Simulation technology provides a good platform to test the perception system of autonomous vehicle. Focus on the sensor simulation modeling of autonomous vehicle perception system, from the perspective of single sensor simulation, multi-sensor simulation and classic simulation platform including millimeter wave radar, lidar and camera, the existing research are reviewed, and the shortcomings and development trends of simulation modeling of …


Anomaly Detection Method Of Electrical Power Consumption Based On Deep Autoencoder, Ningke Sun, Yan Wang, Zhicheng Ji Dec 2022

Anomaly Detection Method Of Electrical Power Consumption Based On Deep Autoencoder, Ningke Sun, Yan Wang, Zhicheng Ji

Journal of System Simulation

Abstract: Aiming at the nonlinear and non-stationary characteristics of electrical power consumption data, an abnormal electrical power consumption detection model based on deep autoencoder is proposed. Gated recurrent unit (GRU) network of the deep learning is combined with autoencoder structure, and the encoder and decoder parts of traditional autoencoder are realized by gated recurrent unit network, which gives full play to the data feature extraction capability of gated recurrent unit and the data reconstruction function of autoencoder structure. Based on the reconstruction error between original data and reconstructed data, abnormal data points of the electrical power consumption are detected. By …


Short-Term Prediction Method Of Wind Power Based On Blp-Alo-Svm, Yefeng Jiao, Yan Wang, Zhicheng Ji Dec 2022

Short-Term Prediction Method Of Wind Power Based On Blp-Alo-Svm, Yefeng Jiao, Yan Wang, Zhicheng Ji

Journal of System Simulation

Abstract: To effectively predict the short-term wind power and its fluctuation range, a prediction method based on hybrid algorithm-optimized support vector machine is proposed. Exploratory data analysis is used to preprocess the original wind speed data to improve the data quality. Chaotic map, Levy flight strategy and particle swarm optimization are used to improve the ant lion algorithm. The support vector machine model optimized by hybrid algorithm is used to predict the wind power. The experimental results show that, compared with the new wind power prediction model, the prediction error of the output results of the method is lower, and …


Long-Term Resilience Simulation On Low-Carbon Urban Grid Based On Evolutionary Game, Zhengda Cui, Weiqiang Yao, Qin Xu, Chen Fang, Ying Chen Dec 2022

Long-Term Resilience Simulation On Low-Carbon Urban Grid Based On Evolutionary Game, Zhengda Cui, Weiqiang Yao, Qin Xu, Chen Fang, Ying Chen

Journal of System Simulation

Abstract: Because of the more frequent extreme disasters, the resilience of urban grid becomes more important. In the background of carbon neutralization policy, the decarbonization transition of urban grid also affects the development of grid resilience. An evolutionary game is used to simulate the resilience evolution of low-carbon urban grid and the evolution model is constructed. The decision to install photovoltaic and energy storage system for residents and to upgrade the grid for resilience is considered in the model and the stability conditions of equilibriums of the evolutionary game are analyzed. The resilience evolution simulation model considering disaster stochasticity is …


Simulation-Driven Based Utility Evaluation And Recommendation Of Expressway Proactive Speed Limit, Geqi Qi, Sijin Liu, Yikang He, Meng Wang, Ailing Huang Dec 2022

Simulation-Driven Based Utility Evaluation And Recommendation Of Expressway Proactive Speed Limit, Geqi Qi, Sijin Liu, Yikang He, Meng Wang, Ailing Huang

Journal of System Simulation

Abstract: Outside the specific punishment area, the traditional roadside passive speed limit mode lacks traffic management, and thus which indirectly leads to the inconsistency or even sudden change of vehicle behaviors in time and space, thereby affects the traffic efficiency and safety. Focusing on the proactive speed limit mode at vehicle side, a utility evaluation and recommendation method is proposed, which carries out the multi-scenario traffic simulation for varied proactive and passive speed limit considering road line types, traffic flow and vehicle type proportion. From the two perspectives of safety and efficiency, the utility evaluation indicators and weights are extracted …


Simulation On Flood Disaster In Urban Building Complex System Based On Lbm, Shen Zhang, Zewang Yang, Yifan Wang, Liang Sun, Ming Cheng, Fankai Meng, Ting Li Dec 2022

Simulation On Flood Disaster In Urban Building Complex System Based On Lbm, Shen Zhang, Zewang Yang, Yifan Wang, Liang Sun, Ming Cheng, Fankai Meng, Ting Li

Journal of System Simulation

Abstract: Because of the extreme climate change, the potential flood disaster risk in the southeast coastal areas of China can not be ignored. Based on lattice Boltzmann computational fluid dynamics method, a three-dimensional simulation study of waterlogging process in tsunami impact scenario is carried out for a coastal city building complex system, and the reliability and accuracy of the numerical simulation method for the flood impact test of an ideal building complex are verified. The results show that the buildings along rivers and coastlines have obvious cloaking effect, while the buildings inside the city are less affected by floods. The …


Research On Modeling And Simulation Technology Of Microwave Radar High Precision Tracking Loop, Jiaji Lou, Jing Ma, Xiaowei Li, Yue Zhao, Youbin Song Dec 2022

Research On Modeling And Simulation Technology Of Microwave Radar High Precision Tracking Loop, Jiaji Lou, Jing Ma, Xiaowei Li, Yue Zhao, Youbin Song

Journal of System Simulation

Abstract: Aiming at the key problem of high-precision tracking loop design of a measurement radar for the weak signal (low carrier to noise ratio signal) in dynamic environment, the design and optimization methods of carrier tracking loop and code tracking loop are focused on. A signal structure with a single carrier as a pilot is proposed, and the loop structure of the frequency-locked loop and the phase-locked loop working together is studied. The modeling and simulation on the two structures show that for the week signal tracking in a dynamic environment, the loop combination structure of the frequency-serial auxiliary …


Research On Parameter Construction Method Of Blue Army Equipment Model Based On A Deep Network, Boyuan Zhang, Guanghong Gong, Ze Wang, Ni Li Dec 2022

Research On Parameter Construction Method Of Blue Army Equipment Model Based On A Deep Network, Boyuan Zhang, Guanghong Gong, Ze Wang, Ni Li

Journal of System Simulation

Abstract: The modeling of blue army equipment is an indispensable part of adversarial simulation environment construction. Aiming at the limited available parameters of "information-poor" and "small sample" characteristics to the blue system, a deep network-based method is proposed to generate the parameters of blue army equipment model. By injecting the information into the simulation model of the blue army equipment, the simulation data is generated and trained in the deep neural network. The obtained network has a certain generalization ability to the unknown parameters prediction of the same type of equipment and can be used directly in prediction or be …


Multi-Robot Path Planning Based On Cbs Algorithm, Qiao Qiao, Yan Wang, Zhicheng Ji Dec 2022

Multi-Robot Path Planning Based On Cbs Algorithm, Qiao Qiao, Yan Wang, Zhicheng Ji

Journal of System Simulation

Abstract: Aiming at the long multi-robot planning path and long one-way search running time of conflict-based search(CBS) in the multi-agent path finding(MAPF), an improved CBS algorithm is proposed, which in a two-way A* focus search is used to optimize the search direction and search method. The suboptimal factorωis introduced into the underlying search function of the CBS algorithm to improve the efficiency of path search. The one-way search in the conflict search algorithm is optimized to a two-way A* search. The experimental results show that the path cost of the improved CBS algorithm is shortened …


Research On Emotional Contagion And Intervention Strategy Of Indoor Evacuation Based On Risk Perception, Yang Zeng, Jinling Li, Haixiang Guo, Weiming Chen Dec 2022

Research On Emotional Contagion And Intervention Strategy Of Indoor Evacuation Based On Risk Perception, Yang Zeng, Jinling Li, Haixiang Guo, Weiming Chen

Journal of System Simulation

Abstract: Aiming at the panic emotion contagion in the indoor emergency evacuation with multi-exit and multi-obstacle, an emotional contagion model is constructed on personality traits, risk perception differences of age and gender, and consciousness regulation. The simulation is carried out by using AnyLogic, which combines individual emotions with evacuation speed to realize the real-time updating of emotional state and speed. That personnel intervention in the process of evacuation can effectively alleviate the spread of panic emotion, is verified and can provide the theoretical basis for panic contagion in the process of emergency evacuation. The results show that the degree of …


Research On Complex Combat Network Dynamic Evolution Based On Information Entropy, Lianyi Zhang, Xisheng Shen, Duzheng Qing, Han Zhang, Min Zhou, Xifu Wang Dec 2022

Research On Complex Combat Network Dynamic Evolution Based On Information Entropy, Lianyi Zhang, Xisheng Shen, Duzheng Qing, Han Zhang, Min Zhou, Xifu Wang

Journal of System Simulation

Abstract: Network-centric warfare, distributed and decentralized command and control gradually replace separately the traditional platform-centric warfare and centralized command and control, and information has become a combat capability. Based on the new information weapon equipment system operation loop, a complex combat network model based on information entropy is constructed, and the combat capability measurement method is proposed. On the basis of the combat capability upgrade being the network driving force, the dynamic evolution rule of the complex combat network is designed and the preferential evolution and stochastic evolution models are constructed. According to a typical system combat example, the influence …


Effect Of Diabetes-Associated Mutations In Kir 6.2/Sur1 On Katp Channel Activities, Yunpeng Li Dec 2022

Effect Of Diabetes-Associated Mutations In Kir 6.2/Sur1 On Katp Channel Activities, Yunpeng Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Maturity Onset Diabetes of the Young (MODY) is a type of diabetes, distinct from either type I or type II, that happens before age 25 (MedlinePlus, 2022). Unlike the other two more common forms of diabetes, MODY is classified as a series of monogenetic disorders (American Diabetes Association Professional Practice Committee, 2021), caused by autosomal mutations. MODY is typically characterized by insufficient secretion of insulin, a similar symptom to type I diabetes, classified into 14 different types based on mutations found on different genes. Among them, subtypes 12 and 13, also called neonatal diabetes mellitus (NDM), are caused by gain-of-function …


Low Voltage Ride-Through Modeling For Wind Turbines Based On Neural Odes, Qiping Lai, Tannan Xiao, Dongsheng Li, Chen Shen Dec 2022

Low Voltage Ride-Through Modeling For Wind Turbines Based On Neural Odes, Qiping Lai, Tannan Xiao, Dongsheng Li, Chen Shen

Journal of System Simulation

Abstract: Considering the difficulty of equivalent modeling of low voltage ride-through(LVRT) characteristics of a wind farm, a neural ordinary differential equation(ODE)-based wind farm LVRT modeling methodis proposed. The input of the model is the voltage and wind speed of each wind turbine at the grid connection point of wind farm, and the output is the current at the grid connection point. The model can better characterize the strong nonlinear switching process and describe LVRT characteristics of wind farms under different wind speed scenarios. A simulation example of a wind farm including three doubly-fed induction generators(DFIGs) is established on …


Simulation Research On Appearance Detection Of Ampoules Based On Lightweight Network And Model Compression, Zhihao Zhu, Yan Wang, Zhicheng Ji Dec 2022

Simulation Research On Appearance Detection Of Ampoules Based On Lightweight Network And Model Compression, Zhihao Zhu, Yan Wang, Zhicheng Ji

Journal of System Simulation

Abstract: Aiming at the large scale and redundant parameters of target detection network model, which result in the difficult to deploy the ampoule bottle appearance defect detection model to edge devices, an LC-Faster R-CNN defect detection algorithm based on lightweight network and model compression is proposed. MobileNet-V2 is used as the backbone, and the redundant channels in the convolutional network are trimmed by model pruning strategy. The floating-point parameters are quantized into integers through saturation truncation mapping. Knowledge distillation is used to restore the accuracy of the compressed network. Tested on the self-built ampoule appearance defect dataset, the model volume …


Fast Generation Method Of Multi-Sensing Channel Fusion Virtual Experiment, Jingwei Deng, Hanwu He, Yueming Wu, Jianhao Su Dec 2022

Fast Generation Method Of Multi-Sensing Channel Fusion Virtual Experiment, Jingwei Deng, Hanwu He, Yueming Wu, Jianhao Su

Journal of System Simulation

Abstract: Aiming at the low development efficiency and single experience in traditional virtual experiments, a rapid generation method of multi-sensing channel fusion virtual experiment visualization is proposed. The experimental steps and sequence of experimental steps of the virtual experiment are defined. A parameterized description method of experimental elements based on Petri net is proposed to describe the sequence of experimental steps, which breaks through the constraints the established procedure steps of traditional virtual experiments and supports the exploratory virtual experiments. The visual expression method of the routing graph and the conversion method between the routing graph and the Petri …


Research On Iterative Calculation And Optimization Methods Of Aero-Engine On-Board Model, Xinghua Luo, Jia Geng, Ming Li, Bei Liu, Lei Wang, Zhiping Song Dec 2022

Research On Iterative Calculation And Optimization Methods Of Aero-Engine On-Board Model, Xinghua Luo, Jia Geng, Ming Li, Bei Liu, Lei Wang, Zhiping Song

Journal of System Simulation

Abstract: Aeroengine is a complex and time-varying multivariable thermophysical system. The research on the convergence accuracy and rate of the component-level model is of great significance to the model-based engine health management, performance and fault-tolerant control. The existing engine component-level models are generally based on the traditional quasi-Newton method to solve the equilibrium equations simultaneously. Compared with the traditional Newton-Raphson method (N-R method), the convergence speed is optimized, but it is difficult to meet accuracy and real-time requirements of the dynamic model airborne applications within the full envelope. An adaptive variable step factor quasi-Newton method is proposed, which can reduce …


Reliability Parameter Optimization Complex System Simulation Based On R-Vikor Method, Zhiguang Wang, Baiting Liu, Xiaolei Wang, Tao Liu, Zhaowei Yang Dec 2022

Reliability Parameter Optimization Complex System Simulation Based On R-Vikor Method, Zhiguang Wang, Baiting Liu, Xiaolei Wang, Tao Liu, Zhaowei Yang

Journal of System Simulation

Abstract: The operation of complex simulation system is not isolated, and always affected by multiple external factors and its own performance. In simulation reliability calculation, parameters need to be chosen, and different performance indexes need to be taken into account when comparing with the reference model. The research is transformed into the multi-attribute decision. An system simulation trusted parameter optimization method based on R-VIKOR(resist rank reversal of visekriterijumska optimizacija | kompromisno resenje) is proposed. Multiple sets of aerodynamic parameters of the new model are obtained through model migration theory, and similarity calculation is carried out with the optimal parameters of …


Sis-Based Modeling And Simulation Analysis On Exercise Benefit Perception Transmission, Lei Wang, Jinhai Sun, Tuojian Li Dec 2022

Sis-Based Modeling And Simulation Analysis On Exercise Benefit Perception Transmission, Lei Wang, Jinhai Sun, Tuojian Li

Journal of System Simulation

Abstract: In order to distinguish the relationship between individual health behavior change and collective health behavior emergence, deal with the challenges of mathematical description of typical health information dissemination processes in social networks and social experiments, SIS(susceptible-infected-susceptible)model is introduced to simulate the dissemination process of classical health information exercise effect perception to meet the requirements of social system complexity, individual diversity and intelligence. To carry out numerical experiments on the propagation process of exercise effect perception to identify the phase change process of the collective health behavior emergence, agent-based modeling and simulation are utilized through NetLogo. Experimental results show …


Research On Low Computational Predictive Control Strategy Of Three-Level Four-Arm Apf, Guifeng Wang, Jinxing Guo Dec 2022

Research On Low Computational Predictive Control Strategy Of Three-Level Four-Arm Apf, Guifeng Wang, Jinxing Guo

Journal of System Simulation

Abstract: Four-arm active power filter(APF) is an ideal device to the power quality of three-phase four-wire distribution network. Owing to the sufficient number of base vectors, three-level four-arm APF has better current tracking performance, but the prediction calculation amount is too large when model predictive current control is applied. A model prediction voltage control strategy based on the idea of space stratification is proposed. Based on the deadbeat control idea and the discrete mathematical model in αβγ coordinate system, the expected reference voltage is predicted from the reference current, and the multiple current predictions are converted into the single voltage …


Implementing Dei In Aviation Education: Coping And Addressing Mental Health Concerns, Jorge L. D. Albelo Ph.D., Michael F. O'Toole Ph.D., Samantha Bowyer Dec 2022

Implementing Dei In Aviation Education: Coping And Addressing Mental Health Concerns, Jorge L. D. Albelo Ph.D., Michael F. O'Toole Ph.D., Samantha Bowyer

Publications

In recent years, different global events have led to increased awareness of the benefits of promoting diversity, equity, and inclusion in the workplace and education. Notably, the aviation industry is seeing increased research initiatives to promote DEI among all generations. Nevertheless, given the rising concerns about mental health in higher education, this paper sought to connect coping and addressing mental health through implementing DEI teachings in aviation education. Integrating DEI in the aviation classroom can be challenging, as many faculty members might feel uncomfortable addressing the topic in their courses. Consequently, the researchers proposed and tested an aviation education approach …


Weakly-Supervised Learning Method For The Recognition Of Potato Leaf Diseases, Junde Chen, Xiaofang Deng, Yuxin Wen, Weirong Chen, Adnan Zeb, Defu Zhang Dec 2022

Weakly-Supervised Learning Method For The Recognition Of Potato Leaf Diseases, Junde Chen, Xiaofang Deng, Yuxin Wen, Weirong Chen, Adnan Zeb, Defu Zhang

Engineering Faculty Articles and Research

As a crucial food crop, potatoes are highly consumed worldwide, while they are also susceptible to being infected by diverse diseases. Early detection and diagnosis can prevent the epidemic of plant diseases and raise crop yields. To this end, this study proposed a weakly-supervised learning approach for the identification of potato plant diseases. The foundation network was applied with the lightweight MobileNet V2, and to enhance the learning ability for minute lesion features, we modified the existing MobileNet-V2 architecture using the fine-tuning approach conducted by transfer learning. Then, the atrous convolution along with the SPP module was embedded into the …


Three-Component Composite Phase-Change Material For Thermal Regulation, Bidisha Ojha Dec 2022

Three-Component Composite Phase-Change Material For Thermal Regulation, Bidisha Ojha

McKelvey School of Engineering Graduate Student Theses & Dissertations

Phase change materials can increase the efficiency of many energy-intensive applications, such as solar power plants, solar heating and cooling systems, heat recovery systems, photovoltaic electricity systems, and Earth satellite systems. In several proposed thermal management systems for high power electronic equipment, PCMs change phase and absorb latent heat at peak energy loads during operation, then dissipate this energy later to prevent overheating. More specifically, composite PCM’s, consisting of an organic material (e.g., paraffin) and an inorganic material (e.g., metallic alloys or salt hydrates), provide a superior balance of thermal conductivity and latent heat for thermal management. Organic PCMs have …


Chitosan Oligosaccharides As A Nanomaterial Platform: Biological Properties And Applications In The Biomedical And Pharmaceutical Fields, Muhamad Alif Razi Dec 2022

Chitosan Oligosaccharides As A Nanomaterial Platform: Biological Properties And Applications In The Biomedical And Pharmaceutical Fields, Muhamad Alif Razi

Makara Journal of Science

Chitosan oligosaccharides (COS) have been introduced as marine-derived biomaterials with potential health benefits and good water solubility properties. This study presents an overview of the promising nanomaterial platform for biomedical and pharmaceutical applications of COS. The health benefits of COS, primarily their antioxidant and protective effects, anti-inflammatory activity, antidiabetic properties, and cholesterol-lowering effects are discussed. Furthermore, the promising recent articles on specific topics such as drug delivery systems and nanobiomaterials, are highlighted


Developing An In Vitro Validated 3d In Silico Internal Carotid Artery Sidewall Aneurysm Model, Hang Yi, Zifeng Yang, Mark Johnson, Luke Bramlage, Bryan Ludwig Dec 2022

Developing An In Vitro Validated 3d In Silico Internal Carotid Artery Sidewall Aneurysm Model, Hang Yi, Zifeng Yang, Mark Johnson, Luke Bramlage, Bryan Ludwig

Mechanical and Materials Engineering Faculty Publications

Introduction: Direct quantification of hemodynamic factors applied to a cerebral aneurysm (CA) remains inaccessible due to the lack of technologies to measure the flow field within an aneurysm precisely. This study aimed to develop an in vitro validated 3D in silico patient-specific internal carotid artery sidewall aneurysm (ICASA) model which can be used to investigate hemodynamic factors on the CA pathophysiology. Methods: The validated ICASA model was developed by quantifying and comparing the flow field using particle image velocimetry (PIV) measurements and computational fluid dynamics (CFD) simulations. Specifically, the flow field characteristics, i.e., blood flowrates, normalized velocity profiles, flow streamlines, …


Magnetized Inulin By Fe3o4 As A Bio-Nano Adsorbent For Treating Water Contaminated With Methyl Orange And Crystal Violet Dyes, Kamran Valizadeh, Amir Bateni, Nazanin Sojoodi, Maryam Rostami Ataabadi, Amir Hossein Behroozi, Ali Maleki, Zhenjiang You Dec 2022

Magnetized Inulin By Fe3o4 As A Bio-Nano Adsorbent For Treating Water Contaminated With Methyl Orange And Crystal Violet Dyes, Kamran Valizadeh, Amir Bateni, Nazanin Sojoodi, Maryam Rostami Ataabadi, Amir Hossein Behroozi, Ali Maleki, Zhenjiang You

Research outputs 2022 to 2026

Current work focuses on fabricating a new bio-nano adsorbent of Fe3O4@inulin nanocomposite via an in-situ co-precipitation procedure to adsorb methyl orange (MO) and crystal violet (CV) dyes from aqueous solutions. Different physical characterization analyses verified the successful fabrication of the magnetic nanocomposite. The adsorbent performance in dye removal was evaluated by varying initial dye concentration, adsorbent dosage, pH and temperature in 5110 mg/L, 0.10.8 g/L, 111 and 283 – 338 K, respectively. Due to the pH of zero point of charge and intrinsic properties of dyes, the optimum pHs were 5 and 7 for MO and …


Phase-Averaged, Frequency Dependence Of Jet Dynamics In A Scaled Up Vocal Fold Model With Full And Incomplete Closure, Nathaniel Wei, Abigail Haworth, Hunter Ringenberg, Michael Krane, Timothy Wei Dec 2022

Phase-Averaged, Frequency Dependence Of Jet Dynamics In A Scaled Up Vocal Fold Model With Full And Incomplete Closure, Nathaniel Wei, Abigail Haworth, Hunter Ringenberg, Michael Krane, Timothy Wei

Department of Mechanical and Materials Engineering: Faculty Publications

This study focuses on frequency dependence effects on glottal jet dynamics with a focus on the physiological condition in which the vocal folds do not fully close. Incomplete closure occurs naturally in children and adult females. But there are also pathological conditions that can be problematic. Experiments were conducted using a 10× scaled-up model in a free surface water tunnel. Two-dimensional vocal fold models with semicircular medial surfaces were stepper motor driven inside a square duct with constant opening and closing speeds. Cases with complete vocal fold closure and incomplete closure to only 15% of the maximum gap were examined. …


Highly Power Dense Dc To Three-Phase Ac Modular Converters With Tiny Module Capacitors, Wiwin Hartini Lew Dec 2022

Highly Power Dense Dc To Three-Phase Ac Modular Converters With Tiny Module Capacitors, Wiwin Hartini Lew

Dissertations and Theses

A Modular Multilevel Converter (MMC) is an attractive candidate in high power conversion due to its modularity and scalability. The energy storage element, namely the module capacitance in the MMC submodule circuit, is typically large and when scaled to convert high power, requires very bulky module capacitors. In addition to deteriorating the power density, the design necessitates the use of electrolytic capacitors, which further affects the overall converter efficiency and reliability. This research presents an MMC submodule topology and the accompanying modulation approach that reduces the submodule capacitance requirements significantly compared to conventional MMC topology (few micro-farads versus several milli-farads). …


Colorado River Basin Water Accounts: 1-Page Summary, David E. Rosenberg Dec 2022

Colorado River Basin Water Accounts: 1-Page Summary, David E. Rosenberg

Civil and Environmental Engineering Faculty Publications

26 Colorado River managers and experts constructively improved basin water accounts as a framework to transition emergency reservoir operations into more sustainable, equitable, and adaptive water uses.