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Articles 1 - 25 of 25
Full-Text Articles in Engineering Science and Materials
Method Of Transferring Strained Semiconductor Structure, Michael Nastasi
Method Of Transferring Strained Semiconductor Structure, Michael Nastasi
Department of Mechanical and Materials Engineering: Faculty Publications
The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having surface contaminants. An interface that includes the contaminants if formed in between the deposited layer and the substrate. Hydrogen atoms are introduced into the structure and allowed to diffuse to the interface. Afterward, the deposited multilayer structure is bonded to a second substrate and is separated away at the interface, which results in transferring a multilayer structure from one substrate at least one strained semiconductor layer and at least one strain-induced seed layer. The strain-induced seed layer can be …
Cyclic Voltammetric And In-Situ Ftir Spectroscopic Studies Of Adsorption And Reduction Of No On Electrode Of Pt Nanoparticles, Qian Cheng, Yan-Xia Jiang, Dong-Mei Zeng, Shi-Gang Sun
Cyclic Voltammetric And In-Situ Ftir Spectroscopic Studies Of Adsorption And Reduction Of No On Electrode Of Pt Nanoparticles, Qian Cheng, Yan-Xia Jiang, Dong-Mei Zeng, Shi-Gang Sun
Journal of Electrochemistry
Adsorption and reduction of NO on electrode of Pt nanoparticles in acid solutions were studied by means of cyclic voltammetry(CV) and in-situ FTIR spectroscopy.The results indicated that the reduction of NO is a complicated process including the adsorption of NO on electrode surface.Two types of surface-bonded NO were determined on Pt nanoparticles.The weakly adsorbed NO was reduced between 0.6 V and-0.05 V,which yielded nitrous oxide(N2O) and ammonium(NH+4) as products;while the strongly bonded NO was reduced at more negative potentials between-0.05V and-0.15V,producing only NH4+ species.
Synthesis And Electrocatalytic Properties Of Ni-Pd/C Catalysts With Pd-Enriched Surface, Yu-Mei Chen, Zhi-Xiu Liang, Sheng-Li Chen
Synthesis And Electrocatalytic Properties Of Ni-Pd/C Catalysts With Pd-Enriched Surface, Yu-Mei Chen, Zhi-Xiu Liang, Sheng-Li Chen
Journal of Electrochemistry
The Ni-Pd alloy catalysts with Pd-enriched surface were synthesized through a modified polyol process.The synthesized materials were investigated by XRD and electrochemical methods,and tested as electrocatalysts for CH3OH-tolerant oxygen reduction.The results indicated that the synthesized Ni-Pd nanoparticles possess multiple phases containing Pd-Ni alloy and pure Ni.Comparing with Pd/C,the prepared Ni-Pd/C nanoparticles exhibited better resolved voltammetric peaks between the hydrogen absorption and adsorption,and positively shifted current peaks for the reduction of Pd oxide.The prepared Ni-Pd alloys with Pd-enriched surface have significantly enhanced ORR activity and improved CH3OH tolerance as comparing with Pd/C catalysts.
Preparation Of Pt Nanoflower/Zno Composites Arrays And Their Electrocatalysis For Methanol Oxidation, Li Gao, Yi-Feng E, Lou-Zhen Fan
Preparation Of Pt Nanoflower/Zno Composites Arrays And Their Electrocatalysis For Methanol Oxidation, Li Gao, Yi-Feng E, Lou-Zhen Fan
Journal of Electrochemistry
The Pt nanoflower/ZnO(PtNF/ZnO) nanorod composites arrays were electrochemically prepared by controlling the hydrophobicity and the hydrophilicity of ZnO nanorods arrays.The Pt nanoflowers grew on the tip of ZnO nanorods,which maintain the vertical array of Zno nanorods with a high degree of size uniformity and high surface area.Compared with Pt nanoparticle covered ZnO nanorod arrays,which were prepared by controlling the hydrophilicities of ZnO nanorods and Pt nanoparticles,the PtNF/ZnO displayed highest electrocatalytic activities for the oxidation of methanol.
Complex Reduction Preparation Of Carbon Supported Pd Nanoparticle Catalyst And Its Electrocatalysis For Formic Acid Oxidation, Wei He, Yong-Yin Kang, Chong Du, Zhi-Qing Zou, Xiao-Gang Zhang, Hui Yang
Complex Reduction Preparation Of Carbon Supported Pd Nanoparticle Catalyst And Its Electrocatalysis For Formic Acid Oxidation, Wei He, Yong-Yin Kang, Chong Du, Zhi-Qing Zou, Xiao-Gang Zhang, Hui Yang
Journal of Electrochemistry
A simple procedure involved the complexing of PdCl2 with sodium citrate followed by ethylene glycol reduction has been employed for the preparation of carbon-supported Pd nanoparticles(Pd/C).The XRD and TEM characterizations indicate that Pd nanoparticles with a small particle size were well-dispersed on carbon support.The mean particle sizes of the Pd/C catalysts were found to be increased from 2.7 to 5.8 nm with heat-treatments at different temperature.The mass activity of the Pd/C catalyst for formic acid electrooxidation increased with the decrease in Pd particle size.However,the specific activity increased with Pd particle size.Furthermore,the Pd/C catalyst with a particle size of ca.3.6 nm …
Progresses In Electrocatalysis Of Nanomaterials—Tuning The Surface Structure And Property Of Electrocatalysts, Yan-Xia Jiang, Na Tian, Zhi-You Zhou, Sheng-Pei Chen, Shi-Gang Sun
Progresses In Electrocatalysis Of Nanomaterials—Tuning The Surface Structure And Property Of Electrocatalysts, Yan-Xia Jiang, Na Tian, Zhi-You Zhou, Sheng-Pei Chen, Shi-Gang Sun
Journal of Electrochemistry
The property of an electrocatalyst depends strongly on its surface structure.The study of surface structure-catalytic functionality is the base of design and preparation of electrocatalysts of high activity,high stability and high selectivity at microstructure level.In this paper,based mainly on our results concering hydrogen and oxygen adsorption-desorption,ethylene glycol oxidation and CO2 reduction,the research progresses in tuning the surface structure and property of electrocatalysts are summarized.This paper overviews firstly the cyclic voltammetric characteristics,electrocatalytic properties of platinum single crystal planes lying on different crystallographic zones of the unit stereographic triangle of face-centered cubic(fcc) metals.Next,the innovation of electrochemical methods to control the surface structure …
Enhanced Visible Light Photoelectrochemical Performances With Nitrogen Doped Tio_2 Nanowire Arrays, Xiao-Jun Lv, Yue-Ming Li, Hao Zhang, Da Chen, Hensel Jennifer, Z Zhang Jin, Jing-Hong Li
Enhanced Visible Light Photoelectrochemical Performances With Nitrogen Doped Tio_2 Nanowire Arrays, Xiao-Jun Lv, Yue-Ming Li, Hao Zhang, Da Chen, Hensel Jennifer, Z Zhang Jin, Jing-Hong Li
Journal of Electrochemistry
Self-organized anodic anatase TiO2nanowire arrays doped with nitrogen have been successfully fabri-cated and their photoelectrochemical(PEC) properties have been characterized and found to be substantially im-proved compared to undoped nanowires or commercial P25 nanoparticles.Photocurrent measured with monochro-matic incident light showed that the incident photon-to-current efficiency(IPCE,%) values of nanowire arrayelectrodes with or without N-doping were obviously higher than that of commercial P25 nanoparticle electrodes,and nitrogen-doped TiO2nanowire arrays(NTNA) had noticeable absorption in the visible region.The NTNAelectrodes showed the highest photocurrent density and power conversion efficiency under 100 mW/cm2visiblelight illumination.A maximumolphotoconversion efficiency of 0.52% was achieved for the NTNA sample at anapplied potential of …
Imprinting Polymerfilm On Patterned Substrate, Li Tan, Yen-Peng Kong, Stella W. Pang, Albert F. Yee
Imprinting Polymerfilm On Patterned Substrate, Li Tan, Yen-Peng Kong, Stella W. Pang, Albert F. Yee
Department of Mechanical and Materials Engineering: Faculty Publications
A method of applying a pattern on a topography includes first applying a polymer film to an elastormer member, such as PDMS, to form a pad. The pad is then applied to a substrate having a varying topography under pressure. The polymer film is transferred to the substrate due to the plastic deformation of the polymer film under pressure compared to the elastic deformation of the PDMS member pulls away from the polymer layer, thereby depositing the polymer layer, thereby depositing the polymer layer upon the substrate.
Crystallization And Electrochemical Corrosion Behaviors Of Amorphous And Nanocrystalline Fe-Based Alloys, Xiang Li, Biao Yan, Peng Dong
Crystallization And Electrochemical Corrosion Behaviors Of Amorphous And Nanocrystalline Fe-Based Alloys, Xiang Li, Biao Yan, Peng Dong
Journal of Electrochemistry
In this study,amorphous Fe78Si13B9 and Fe73.5Si13.5B9Nb3Cu1 ribbons were prepared by the chill block melt-spinning process and nanocrystalline Fe73.5Si13.5B9Nb3Cu1 ribbons were obtained by annealing. The amorphous ribbons and their crystallization processes were identified by differential scanning calorimeter (DSC) and X-ray diffraction (XRD). A comparative study of the electrochemical corrosion behaviors of Fe78Si13B9 and Fe73.5Si13.5B9Nb3Cu1 amorphous and nanocrystallized alloys was performed by linear polarization method and electrochemical impedance spectroscopy (EIS) in 1mol/L NaOH solutions. The photographs of the samples after potentiodynamic polarization were observed by SEM. The influence of heat treatment on the alloys structure and corrosion resistance in 1mol/L NaOH solutions …
Redox State Of Polyaniline Nanodot And Its Coulomb Staircase Effect, Jian-Zhang Zhou, Shao-Huang Weng, Zhong-Hua Lin
Redox State Of Polyaniline Nanodot And Its Coulomb Staircase Effect, Jian-Zhang Zhou, Shao-Huang Weng, Zhong-Hua Lin
Journal of Electrochemistry
Polyaniline nanodot array had been fabricated in AAO template with potentiostatic method and the I~V characteristics of nanodots with different redox states were measured by conducting atomic force microscope (C-AFM) in atmosphere at room temperature. We found that only nanodots in partial oxidation state exhibit coulomb staircase in the I~V curves,while those in the full oxidation state and reduced state do not. The above phenomena were discussed preliminarily.
Electrocatalytic Oxidation Of Glucose On Cnt/Nanocrystlline Tio_2-Pt Complex Film Electrode In Ionic Liquids, Dao-Bao Chu, Long-Wu Zha, Shu-Xi Wang, Jian Wang, Ying Xiao, Yuan-Yuan Hou, Jian-Guo He, Xue-Jiao Zhang
Electrocatalytic Oxidation Of Glucose On Cnt/Nanocrystlline Tio_2-Pt Complex Film Electrode In Ionic Liquids, Dao-Bao Chu, Long-Wu Zha, Shu-Xi Wang, Jian Wang, Ying Xiao, Yuan-Yuan Hou, Jian-Guo He, Xue-Jiao Zhang
Journal of Electrochemistry
Using ionic liquid [EMI]BF4 as the electrolyte,the electrocatalytic oxidation of glucose on carbon nanotubes/nanocrystlline TiO2 film loaded on Pt (CNT/nanoTiO2-Pt) complex film electrode was investigated by cyclic voltammetry. The results found that the CNT/nanoTiO2-Pt complex electrode had high catalytic activity to the electrochemical oxidation of glucose in ionic liquids and the oxidation potential was -0.46 V. The best effect of glucose oxidation was obtained with the volume ratio of ionic liquid to water being 3∶1. The process of electrodic reaction process was concentration polarization controlled.
Synthesis And Characterization Of Sulfur-Carbonnanotubes As Cathode Of Lithium/Sulfur Rechargeable Battery, Rui Du, Zhong-Zhi Yuan
Synthesis And Characterization Of Sulfur-Carbonnanotubes As Cathode Of Lithium/Sulfur Rechargeable Battery, Rui Du, Zhong-Zhi Yuan
Journal of Electrochemistry
A carbon-containing composite was synthesized by heating element sulfur and carbon nanotubes. The sulfur-carbonnanotube composites were characterized by X-ray diffraction,SEM,Brunauer-Emmett-Teller.The electrochemical property was characterized by cyclic voltammetry,constant current charge and discharge.It was revealed that the sulfur-carbonnanotube cathode 2016-type coin cells exhibited a good electrochemical property with the initial dicharge specific capacity up to 680 mAh/g and a stable capacity approximately 500 mAh/g after 30 cycle numbers.
Flexible Electronics Using Ion Implantation To Adhere Polymer Substrate To Single Crystal Silicon Substrate, Terry L. Alford, Douglas C. Thompson Jr., Hyunchul Kim, Michael A. Nastasi, James W. Mayer, Daniel Adams
Flexible Electronics Using Ion Implantation To Adhere Polymer Substrate To Single Crystal Silicon Substrate, Terry L. Alford, Douglas C. Thompson Jr., Hyunchul Kim, Michael A. Nastasi, James W. Mayer, Daniel Adams
Department of Mechanical and Materials Engineering: Faculty Publications
An electronic apparatus uses a single crystalline silicon Substrate disposed adjacent to a flexible substrate. The electronic apparatus may be a flexible flat panel display, or a flexible printed circuit board. The flexible substrate can be made from polymer, plastic, paper, flexible glass, and stainless steel. The flexible substrate is bonded to the single crystalline substrate using an ion implantation process. The ion implantation process involves the use of a noble gas Such as hydrogen, helium, Xenon, and krypton. A plurality of semiconductor devices are formed on the single crystalline silicon Substrate. The semi conductor devices may be thin film …
High Utilization Aupt Nanoparticles Supported On Mwcnts For Methanol Electro-Oxidation In Alkaline Medium, Xun Guo, Dao-Jun Guo, Xin-Ping Qiu, Li-Quan Chen, Wen-Tao Zhu
High Utilization Aupt Nanoparticles Supported On Mwcnts For Methanol Electro-Oxidation In Alkaline Medium, Xun Guo, Dao-Jun Guo, Xin-Ping Qiu, Li-Quan Chen, Wen-Tao Zhu
Journal of Electrochemistry
We synthesized gold-platinum electrocatalysts supported on multi-walled carbon nanotubes(MWCNTs) with high utilization by a simple one-step method.A high Pt loading series of bimetallic AuPt/MWCNTs catalysts were prepared by the improved ethylene glycol reduction method,and then were compared in terms of the electrocatalytic activity for methanol electro-oxidation using cyclic voltammetry(CV) and chronoamperometry in alkaline solutions.The structure of AuPt/MWCNTs was characterized by the transmission electron microscopy(TEM),X-ray diffraction(XRD) and energy-dispersive X-ray spectroscopy(EDS).The results showed that the AuPt/MWCNTs catalysts had high Pt utilization,uniform AuPt nanoparticles size and good electrocatalytic activity for methanol electro-oxidation.The effect of Au/Pt mass ratio on electrocatalytic activity was also investigated.The …
Photoelectrochemical Properties Of Tio_2 Nanoparticles, Jie Qu, Ying Li, Qi-Wei Jiang, Xue-Ping Gao
Photoelectrochemical Properties Of Tio_2 Nanoparticles, Jie Qu, Ying Li, Qi-Wei Jiang, Xue-Ping Gao
Journal of Electrochemistry
The protonated titanate nanoparticles were obtained at room temperature and subsequently calcined at different temperatures(300 ℃,400 ℃,500 ℃,600 ℃ and 700 ℃) in air.The obtained products were characterized by XRD,TEM and UV-Vis.It is found that the grain sizes of TiO2 nanoparticles calcined at 300 ℃ were about 20 nm,and increased gradually with the temperature rise.Photoelectric performance was measured with I～V curve and electrochemical impedance spectroscopy(EIS).The TiO2 nanoparticles obtained at 500 ℃ showed the best photoelectrochemical properties with a photovoltaic conversion efficiency of 6.39%,which is much higher than those at other temperatures.In addition,it is also demonstrated that the charge transfer resistance …
Nano-Sn/Hard Carbon Composite As Anode Material For Lithium Ion Batteries, Bing-Kun Guo, Jie Shu, Kun Tang, Ying Bai, Zhao-Xiang Wang, Li-Quan Chen
Nano-Sn/Hard Carbon Composite As Anode Material For Lithium Ion Batteries, Bing-Kun Guo, Jie Shu, Kun Tang, Ying Bai, Zhao-Xiang Wang, Li-Quan Chen
Journal of Electrochemistry
The tin(Sn) nano particles were embedded into the mesopores of hard carbon spherules(HCS) to form a composite anode material for lithium ion batteries.The structure of the obtained composite was characterized by X-ray diffraction(XRD) while its electrochemical performances were evaluated with galvanostatic cycling.It is found that the embedding Sn nanoparticles into porous HCS not only result in a composite material with high lithium storage capacity and capacity retention,but also increase the initial coulombic efficiency of the composite.Based on the infrared spectroscopic analysis,the enhanced initial coulombic efficiency is attributed to the inductive decomposition of the ROCO2Li species in the solid electrolyte interphase(SEI) …
Synthesis,Characteristics And Electrochemical Performance Of Nano-Sized Snco/Graphite Composites As Anode For Lithium Ion Batteries, Jin-Shu Cai, Ling Huang, Fu-Sheng Ke, Shi-Gang Sun
Synthesis,Characteristics And Electrochemical Performance Of Nano-Sized Snco/Graphite Composites As Anode For Lithium Ion Batteries, Jin-Shu Cai, Ling Huang, Fu-Sheng Ke, Shi-Gang Sun
Journal of Electrochemistry
The nano-structural Sn-Co/graphite composites were prepared by chemical reduction of the alloy electroless deposition solution in graphite suspensions,and the composites were annealed at 500 ℃.The phase structure and surface morphology of the composites were measured by XRD、SEM and Raman.The results indicate that there were high dispersions and high loadings of Sn-Co nanoparticles on graphite by thermal treatment.Electrochemical lithium storage performance was studied preliminarily on the obtained samples.The graphite modified with the Sn-Co nanoparticles possessed a higher electrochemical reversible capacity than that of graphite during the charge and discharge process.The appetency between the Sn-Co nanoparticles and graphite can effectively reduce or …
Silicon Nanowires As Anode Materials For Lithium Ion Batteries, Yan-Peng Fu, Hui-Xin Chen, Yong Yang
Silicon Nanowires As Anode Materials For Lithium Ion Batteries, Yan-Peng Fu, Hui-Xin Chen, Yong Yang
Journal of Electrochemistry
The SiNWs electrodes were fabricated by coating and direct growth methods,respectively.The structure,morphology and electrochemical performance of such materials were characterized by XRD,SEM and charge-discharge tests.The results show that the electrodes prepared by direct growth method had higher capacity,better battery life and also displayed and excellent cyclability at higher currents.During the process of lithiation,the initial crystalline Si transformed to amorphous LixSi,and the average diameter of the SiNWs increased.Despite the large volume changed,the SiNWs remained intact and did not break into smaller particles.
Electrochemical Properties Of Functionalized Carbon Nanotubes And Their Applications In Analysis Of 6-Mercaptopurine, Bao-Yi Lu, Yan-Yan Lai, Hong Li
Electrochemical Properties Of Functionalized Carbon Nanotubes And Their Applications In Analysis Of 6-Mercaptopurine, Bao-Yi Lu, Yan-Yan Lai, Hong Li
Journal of Electrochemistry
The electrochemical behaviors and adsorption properties of single-walled carbon nanotubes such as SWNT,SWNT-COOH,and SWNT-OH and multi-walled carbon nanotubes including MWNT,MWNT-COOH,and MWNT-OH modified at a graphite electrode have been investigated by using [Fe(CN)6]3-anion and [Co(phen)3]3+ cation.It was shown that shows good redox reversibility of [Fe(CN)6]3-/4-reactions on the existed carbon nanotubes(CNT) modified electrode.Based on the strong adsorptive property of [Co(phen)3]3+ on the CNT surface,the [Co(phen)3]3+/CNT modified graphite electrode can be obtained by progressive potential sweeping and developed to monitor quantitatively 6-mercaptopurine(6-MP).The adsorption capacity of [Co(phen)3]3+ on the multi-walled carbon nanotubes is higher than that of single-walled carbon nanotubes.For the carbon nanotubes with …
Characterization Of A Viscoelastic Response From Thin Metal Films Deposited On Silicon For Microsystem Applications, Steven L. Meredith
Characterization Of A Viscoelastic Response From Thin Metal Films Deposited On Silicon For Microsystem Applications, Steven L. Meredith
Master's Theses
Understanding the mechanisms that control the mechanical behavior of microscale actuators is necessary to design an actuator that responds to an applied actuation force with the desired behavior. Micro actuators which employ a diaphragm supported by torsional hinges which deform during actuation are used in many applications where device stability and reliability are critical. The material response to the stress developed within the hinge during actuation controls how the actuator will respond to the actuating force. A fully recoverable non-linear viscoelastic response has been observed in electrostatically driven micro actuators employing torsional hinges of silicon covered with thin metal films. …
Identification Of Multiple Oscillation States Of Carbon Nanotube Tipped Cantilevers Interacting With Surfaces In Dynamic Atomic Force Microscopy, Mark Strus, Arvind Raman
Identification Of Multiple Oscillation States Of Carbon Nanotube Tipped Cantilevers Interacting With Surfaces In Dynamic Atomic Force Microscopy, Mark Strus, Arvind Raman
Birck and NCN Publications
Carbon nanotubes (CNTs) have gained increased interest in dynamic atomic force microscopy (dAFM) as sharp, flexible, conducting, nonreactive tips for high-resolution imaging, oxidation lithography, and electrostatic force microscopy. By means of theory and experiments we lay out a map of several distinct tapping mode AFM oscillation states for CNT tipped AFM cantilevers: namely, noncontact attractive regime oscillation, intermittent contact with CNT slipping or pinning, or permanent contact with the CNT in point or line contact with the surface while the cantilever oscillates with large amplitude. Each state represents fundamentally different origins of CNT-surface interactions, CNT tip-substrate dissipation, and phase contrast …
Effects Of Aggregate Structure On Hot-Mix Asphalt Rutting Performance In Low Traffic Volume Local Pavements, Yong-Rak Kim, Hee Mun Park, Francisco Thiago Sacramento Aragão, Jamilla Emi Sudo Lutif
Effects Of Aggregate Structure On Hot-Mix Asphalt Rutting Performance In Low Traffic Volume Local Pavements, Yong-Rak Kim, Hee Mun Park, Francisco Thiago Sacramento Aragão, Jamilla Emi Sudo Lutif
Department of Mechanical and Materials Engineering: Faculty Publications
The objective of this study is to evaluate the effect of mix gradations associated with the Superpave restricted zone on rutting potential specifically for low traffic volume roadways. Although the elim-ination of the restricted zone requirement in Superpave mix design is highly recommended, some questions still remain unanswered as the research conclusions supporting the elimination of the re-stricted zone were largely made for medium to high traffic volume roadways, where aggregates are highly crushed and of good quality. The applicability of such research conclusions based on high traffic volume mixes needs to be verified for low volume mixes because many …
Experimental Investigation Of A Novel Blast Wave Mitigation Device, Zhenbi Su, Wen Peng, Zhaoyan Zhang, George Gogos, Reed Skaggs, Bryan Cheeseman, Chian Fong Yen
Experimental Investigation Of A Novel Blast Wave Mitigation Device, Zhenbi Su, Wen Peng, Zhaoyan Zhang, George Gogos, Reed Skaggs, Bryan Cheeseman, Chian Fong Yen
Department of Mechanical and Materials Engineering: Faculty Publications
A novel blast wave mitigation device was investigated experimentally in this paper. The device consists of a pistoncylinder assembly. A shock wave is induced within the cylinder when a blast wave impacts on the piston. The shock wave propagates inside the device and is reflected repeatedly. The shock wave propagation process inside the device lengthens the duration of the force on the base of the device to several orders of magnitude of the duration of the blast wave, while it decreases the maximum pressure over an order of magnitude. Two types of experiments were carried out to study the blast …
Computational Model For Predicting Nonlinear Viscoelastic Damage Evolution In Materials Subjected To Dynamic Loading, Flavio V. Souza, Yong-Rak Kim, George A. Gazonas, David H. Allen
Computational Model For Predicting Nonlinear Viscoelastic Damage Evolution In Materials Subjected To Dynamic Loading, Flavio V. Souza, Yong-Rak Kim, George A. Gazonas, David H. Allen
Department of Mechanical and Materials Engineering: Faculty Publications
Many inelastic solids accumulate numerous cracks before failure due to impact loading, thus rendering any exact solution of the IBVP untenable. It is therefore useful to construct computational models that can accurately predict the evolution of damage during actual impact/dynamic events in order to develop design tools for assessing performance characteristics. This paper presents a computational model for predicting the evolution of cracking in structures subjected to dynamic loading. Fracture is modeled via a nonlinear viscoelastic cohesive zone model. Two example problems are shown: one for model validation through comparison with a one-dimensional analytical solution for dynamic viscoelastic debonding, and …
Comparison Of Fuzzy Clustering Methods And Their Applications To Geophysics Data, David J. Miller, Carl A. Nelson, Molly Boeka Cannon, Kenneth P. Cannon
Comparison Of Fuzzy Clustering Methods And Their Applications To Geophysics Data, David J. Miller, Carl A. Nelson, Molly Boeka Cannon, Kenneth P. Cannon
Department of Mechanical and Materials Engineering: Faculty Publications
Fuzzy clustering algorithms are helpful when there exists a dataset with subgroupings of points having indistinct boundaries and overlap between the clusters. Traditional methods have been extensively studied and used on real-world data, but require users to have some knowledge of the outcome a priori in order to determine howmany clusters to look for. Additionally, iterative algorithms choose the optimal number of clusters based on one of several performance measures. In this study, the authors compare the performance of three algorithms (fuzzy c-means, Gustafson-Kessel, and an iterative version of Gustafson-Kessel) when clustering a traditional data set as well as real-world …