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Full-Text Articles in Engineering

Macro-/Micro-Controlled 3d Lithium-Ion Batteries Via Additive Manufacturing And Electric Field Processing, Jie Li, Xinhua Liang, Frank W. Liou, Jonghyun Park Dec 2018

Macro-/Micro-Controlled 3d Lithium-Ion Batteries Via Additive Manufacturing And Electric Field Processing, Jie Li, Xinhua Liang, Frank W. Liou, Jonghyun Park

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper presents a new concept for making battery electrodes that can simultaneously control macro-/micro-structures and help address current energy storage technology gaps and future energy storage requirements. Modern batteries are fabricated in the form of laminated structures that are composed of randomly mixed constituent materials. This randomness in conventional methods can provide a possibility of developing new breakthrough processing techniques to build well-organized structures that can improve battery performance. In the proposed processing, an electric field (EF) controls the microstructures of manganese-based electrodes, while additive manufacturing controls macro-3D structures and the integration of both scales. The synergistic control ...


Experimental Study On The Influence Of Slickwater On Shale Permeability, Zhonghua Liu, Baojun Bai, Zheyu Zhang, Jing Tang, Shunpeng Zeng, Xiaogang Li Dec 2018

Experimental Study On The Influence Of Slickwater On Shale Permeability, Zhonghua Liu, Baojun Bai, Zheyu Zhang, Jing Tang, Shunpeng Zeng, Xiaogang Li

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

There are two diametrically opposite views of the influence of slickwater on shale permeability among scholars at home and abroad. We used the shale outcrops rock samples from the Lower Silurian Longmaxi Formation in Sichuan Basin. The permeability of these dry samples before and after immersion in different solution systems were tested by pulse attenuation method. The experimental results show that the impregnation of different slickwater components and standard salt solution can promote the increase of the permeability of shale samples. The stress sensitivity of shale samples after liquid immersion is medium weak to weak. The sample stress sensitivity is ...


Spin-Controlled Wavefront Shaping With Plasmonic Chiral Geometric Metasurfaces, Yang Chen, Xiaodong Yang, Jie Gao Dec 2018

Spin-Controlled Wavefront Shaping With Plasmonic Chiral Geometric Metasurfaces, Yang Chen, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metasurfaces, as a two-dimensional (2D) version of metamaterials, have drawn considerable attention for their revolutionary capability in manipulating the amplitude, phase, and polarization of light. As one of the most important types of metasurfaces, geometric metasurfaces provide a versatile platform for controlling optical phase distributions due to the geometric nature of the generated phase profile. However, it remains a great challenge to design geometric metasurfaces for realizing spin-switchable functionalities because the generated phase profile with the converted spin is reversed once the handedness of the incident beam is switched. Here, we propose and experimentally demonstrate chiral geometric metasurfaces based on ...


Sensor-Enhanced Analysis And Behavior Of Steel Beams In Fire, Genda Chen Oct 2018

Sensor-Enhanced Analysis And Behavior Of Steel Beams In Fire, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Traditionally, strain data are difficult, if not impossible, to obtain from steel structures in fire due to their harsh environment and temperature measurements are limited to the locations of thermocouples. This paper presents high-temperature measurements using a Brillouin scattering based (distributed) fiber optic sensor and the application of the measured temperatures and material parameters recommended in building codes into the enhanced thermo-mechanical analysis of simply-supported steel beams subjected to combined thermal and loading effects. The distributed temperature sensor captures detailed, non-uniform temperature distributions that are compared locally with thermocouple measurements by less than 5% at a 95% confidence level. The ...


Explosive Dust Test Vessel Comparison Using Pulverized Pittsburgh Coal, Jacob Miller, Jay Schafler, Phillip R. Mulligan, Robert Eades, Kyle A. Perry, Catherine E. Johnson Oct 2018

Explosive Dust Test Vessel Comparison Using Pulverized Pittsburgh Coal, Jacob Miller, Jay Schafler, Phillip R. Mulligan, Robert Eades, Kyle A. Perry, Catherine E. Johnson

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Explosions of coal dust are a major safety concern within the coal mining industry. The explosion and subsequent fires caused by coal dust can result in significant property damage, loss of life in underground coal mines and damage to coal processing facilities. The United States Bureau of Mines conducted research on coal dust explosions until 1996 when it was dissolved. In the following years, the American Society for Testing and Materials (ASTM) developed a test standard, ASTM E1226, to provide a standard test method characterizing the “explosibility” of particulate solids of combustible materials suspended in air. The research presented herein ...


Toward Autonomous Wall-Climbing Robots For Inspection Of Concrete Bridges And Tunnels, Jizhong Xiao Sep 2018

Toward Autonomous Wall-Climbing Robots For Inspection Of Concrete Bridges And Tunnels, Jizhong Xiao

Archived Webinars

In addition to visual inspection for surface flaws, inspectors are often required to detect subsurface defects (e.g., delamination and voids) using nondestructive evaluation (NDE) instruments, such as ground penetration radar (GPR) and impact sounding device, in order to determine the structural integrity of bridges and tunnels. In these cases, access to critical locations for reliable and safe inspections is a challenge.

Since 2002, Dr. Jizhong Xiao’s group has developed four generations of wall-climbing robots for NDE inspection of bridges and tunnels. These robots combine the advantages of aerodynamic attraction and suction to achieve a desirable balance of strong ...


Optical-Fiber-Based Smart Concrete Thermal Integrity Profiling: An Example Of Concrete Shaft, Ruoyu Zhong, Ruichang Guo, Wen Deng Sep 2018

Optical-Fiber-Based Smart Concrete Thermal Integrity Profiling: An Example Of Concrete Shaft, Ruoyu Zhong, Ruichang Guo, Wen Deng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Concrete is currently the most widely used construction material in the world. The integrity of concrete during the pouring process could greatly affect its engineering performance. Taking advantage of heat production during the concrete curing process, we propose an optical-fiber-based thermal integrity profiling (TIP) method which can provide a comprehensive and accurate evaluation of the integrity of concrete immediately after its pouring. In this paper, we use concrete shaft as an example to conduct TIP by using the optical fiber as a temperature sensor which can obtain high spatial resolution temperature data. Our method is compared with current thermal infrared ...


An Overview Of Direct Current Distribution System Architectures & Benefits, Venkata Anand Prabhala, Bhanu Prashant Baddipadiga, Poria Fajri, Mehdi Ferdowsi Sep 2018

An Overview Of Direct Current Distribution System Architectures & Benefits, Venkata Anand Prabhala, Bhanu Prashant Baddipadiga, Poria Fajri, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper examines existing and future direct current (DC) distribution systems with a wide range of applications in data centers, telecommunication systems, commercial buildings, residential homes, electric vehicles, spacecraft, and aircrafts. DC distribution systems have many advantages and disadvantages over their alternating current (AC) counterparts. There are a few surviving examples of DC distribution systems; among them are the telecommunication systems and data centers that use the low-voltage 48 Vdc systems. However, recently, there has been a move towards higher DC bus voltages. In this paper, a comparative study of different DC distribution architectures and bus structures is presented and ...


Shape-Based Separation Of Micro-/Nanoparticles In Liquid Phases, Behrouz Behdani, Saman Monjezi, Mason J. Carey, Curtis G. Weldon, Jie Zhang, Cheng Wang, Joontaek Park Sep 2018

Shape-Based Separation Of Micro-/Nanoparticles In Liquid Phases, Behrouz Behdani, Saman Monjezi, Mason J. Carey, Curtis G. Weldon, Jie Zhang, Cheng Wang, Joontaek Park

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The production of particles with shape-specific properties is reliant upon the separation of micro-/nanoparticles of particular shapes from particle mixtures of similar volumes. However, compared to a large number of size-based particle separation methods, shape-based separation methods have not been adequately explored. We review various up-to-date approaches to shape-based separation of rigid micro-/nanoparticles in liquid phases including size exclusion chromatography, field flow fractionation, deterministic lateral displacement, inertial focusing, electrophoresis, magnetophoresis, self-assembly precipitation, and centrifugation. We discuss separation mechanisms by classifying them as either changes in surface interactions or extensions of size-based separation. The latter includes geometric restrictions and ...


A Spatio-Temporal Model Reveals Self-Limiting Fcɛri Cross-Linking By Multivalent Antigens, Md Shahinuzzaman, Jawahar Khetan, Dipak Barua Sep 2018

A Spatio-Temporal Model Reveals Self-Limiting Fcɛri Cross-Linking By Multivalent Antigens, Md Shahinuzzaman, Jawahar Khetan, Dipak Barua

Chemical and Biochemical Engineering Faculty Research & Creative Works

Aggregation of cell surface receptor proteins by multivalent antigens is an essential early step for immune cell signalling. A number of experimental and modelling studies in the past have investigated multivalent ligand-mediated aggregation of IgE receptors (FcɛRI) in the plasma membrane of mast cells. However, understanding of the mechanisms of FcɛRI aggregation remains incomplete. Experimental reports indicate that FcɛRI forms relatively small and finite-sized clusters when stimulated by a multivalent ligand. By contrast, modelling studies have shown that receptor cross-linking by a trivalent ligand may lead to the formation of large receptor superaggregates that ...


Numerical Simulation Study On Miscible Eor Techniques For Improving Oil Recovery In Shale Oil Reservoirs, Dheiaa Alfarge, Mingzhen Wei, Baojun Bai Sep 2018

Numerical Simulation Study On Miscible Eor Techniques For Improving Oil Recovery In Shale Oil Reservoirs, Dheiaa Alfarge, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Shale formations in North America such as Bakken, Niobrara, and Eagle Ford have huge oil in place, 100—900 billion barrels of oil in Bakken only. However, the predicted primary recovery is still below 10%. Therefore, seeking for techniques to enhance oil recovery in these complex plays is inevitable. Although most of the previous studies in this area recommended that CO2 would be the best EOR technique to improve oil recovery in these formations, pilot tests showed that natural gases performance clearly exceeds CO2 performance in the field scale. In this paper, two different approaches have been integrated ...


Rheological Properties Of Warm Mix Asphalt Binders And Warm Mix Asphalt Binders Containing Polyphosphoric Acid, Jun Liu, Kezhen Yan, Jenny Liu Sep 2018

Rheological Properties Of Warm Mix Asphalt Binders And Warm Mix Asphalt Binders Containing Polyphosphoric Acid, Jun Liu, Kezhen Yan, Jenny Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the laboratory investigation of properties of warm mix asphalt (WMA) binders and WMA binders containing polyphosphoric acid (PPA).Two types of warm mix additives were used to produce the WMA binders. Superpave tests were carried out on original and short-term aged binders through the rotational viscometer, the dynamic shear rheometer (DSR), and the bending beam rheometer (BBR). The results indicated that the WMA binders with different warm mix additives showed different viscosity values, however, the addition of PPA remarkably increased the viscosity values of these two kinds of WMA binders used, in the present study, to a ...


Direct Synthesis Of Radioactive Nanoparticles Involving Neutrons, Carlos Henry Castano Giraldo, Maria Camila Garcia Toro, Brian Michael Mills Aug 2018

Direct Synthesis Of Radioactive Nanoparticles Involving Neutrons, Carlos Henry Castano Giraldo, Maria Camila Garcia Toro, Brian Michael Mills

Mining and Nuclear Engineering Faculty Research & Creative Works

A method to synthesize radioactive nanoparticles includes the production of metallic and multimetallic nanoparticles in a single step by providing an aqueous solution of the metal precursor, and irradiating the aqueous solution thereby producing nanoparticles. The obtained nanoparticles include one or more radioactive isotopes of gold, such as 198Au and 199Au as well as radioisotopes of silver when the obtained nanoparticles are bimetallic. The aqueous solution is irradiated in a radiation field that includes neutrons and gamma rays. The radiation field may be provided by a nuclear reactor. The aqueous solution may include silver, and bimetallic nanoparticles may be produced ...


Pedestrian Bridge Test Demonstration, Genda Chen, R. Zoughi Aug 2018

Pedestrian Bridge Test Demonstration, Genda Chen, R. Zoughi

INSPIRE-UTC Annual Meetings

The INSPIRE UTC, with permission and the cooperation of Missouri S&T Facilities Operations, is conducting research testing on the Computer Science Pedestrian Bridge through the end of September 2018. The technologies employed in the Pedestrian Bridge test include: microwave imaging, ground penetrating radar and impact-echo tests, hyperspectral, and thermal imaging.


Developing A Robotic Simulator And Video Games For Professional And Public Training, Sushil Louis Aug 2018

Developing A Robotic Simulator And Video Games For Professional And Public Training, Sushil Louis

INSPIRE-UTC Annual Meetings

Civil engineers are not educated with robotics. They need to be trained on the job with effective tools. The most recent simulation trainer that the PI has built is currently being used by the United States Navy to train surface warfare officers in decision making under stress. In a crowded in-port environment, the crew on a ship’s bridge is trained to probe and identify suspicious boat behavior within the port’s traffic pattern. Officers in charge of the simulation training lesson use software for high-level control of dozens of other ships, boats, and aircrafts that quickly react and adapt ...


Training Framework Of Robotic Operation And Image Analysis For Decision-Making In Bridge Inspection And Preservation, Ruwen Qin Aug 2018

Training Framework Of Robotic Operation And Image Analysis For Decision-Making In Bridge Inspection And Preservation, Ruwen Qin

INSPIRE-UTC Annual Meetings

Inspection and preservation of existing transportation infrastructure to extend their service life is an effective way of mitigating the pressure of steadily growing transportation demands on the aging infrastructure. Their current practice, though, represents one of the most costly operations in state departments of transportation.

The INSPIRE University Transportation Center will develop a remotely-controlled robotic platform that helps with these labor-intensive tasks and allows engineers to focus on decision-making processes. An important mission of INSPIRE is to leverage users’ capability of implementing, and interacting with, the robotic platform. Therefore, a long-term plan has been made to create a framework of ...


Autonomous Wall-Climbing Robots For Inspection And Maintenance Of Concrete Bridges, Jizhong Xiao Aug 2018

Autonomous Wall-Climbing Robots For Inspection And Maintenance Of Concrete Bridges, Jizhong Xiao

INSPIRE-UTC Annual Meetings

Since 2002, the PI’s group has developed four generations of wall-climbing robots for NDE inspection of civil infrastructure. These robots combine the advantages of aerodynamic attraction and suction to achieve a desirable balance of strong adhesion and high mobility. They don’t require perfect sealing and can thus move on smooth and rough surfaces, such as brick, concrete, stucco, wood, glass, and metal. For example, Rise-Rover uses two drive modules to carry their middle compartment with payload up to 450 N. Ground penetrating radar (GPR)-Rover and Mini GPR-Rover are custom designed to carry a GSSI’s GPR antenna ...


Climbing Robots With Automated Deployment Of Sensors And Nde Devices For Steel Bridge Inspection, Hung La Aug 2018

Climbing Robots With Automated Deployment Of Sensors And Nde Devices For Steel Bridge Inspection, Hung La

INSPIRE-UTC Annual Meetings

The PI was a research scientist/faculty at Rutgers University who successfully developed in 2014 a Robotic Assisted Bridge Inspection Tool (RABIT) for bridge deck inspections. Other bridge elements, such as girders and columns, or even underside of bridge decks are difficult to access and remain a challenge for efficient inspection. Like visual inspection, current practices for bridge maintenance are equally time consuming and expensive. Automation of simple maintenance actions such as bearing cleaning and concrete sealing with robots will lead to a leap forward to the next-generation strategy of bridge maintenance.

This project aims to develop and prototype automated ...


Mobile-Manipulating Uavs For Sensor Installation, Bridge Inspection And Maintenance, Paul Oh Aug 2018

Mobile-Manipulating Uavs For Sensor Installation, Bridge Inspection And Maintenance, Paul Oh

INSPIRE-UTC Annual Meetings

Mobile manipulating UAVs have great potential for bridge inspection and maintenance. Since 2002, the PI has developed UAVs that could fly through in-and-around buildings and tunnels. Collision avoidance in such cluttered near-Earth environments has been a key challenge. The advent of light-weight, computationally powerful cameras led to breakthroughs in SLAM even though SLAM-based autonomous aerial navigation around bridges remains an unsolved problem.

In 2007, the PI integrated a mobile manipulation function into UAVs, greatly extending the capabilities of UAVs from passive survey of environments with cameras to active interaction with environments using limbs. Mobile-manipulating UAVs have since been demonstrated to ...


Quantitative Bridge Inspection Ratings Using Autonomous Robotic Systems, Anil Agrawal Aug 2018

Quantitative Bridge Inspection Ratings Using Autonomous Robotic Systems, Anil Agrawal

INSPIRE-UTC Annual Meetings

The 2001 study sponsored by FHWA raised serious concern on the consistency and reliability of visual inspection. Although consistent ratings can be obtained with a good QA/QC program, based on a recent study by the PI, the concern for reliability of defect detection remains. With the adoption of the recent AASHTO Manuel for Bridge Element Inspection, the new inspection approach not only requires rating for bridge elements, but also the location and extent of deterioration. Since autonomous robotic systems generate an enormous amount of inspection data, deducing from the data to a simple rating along with the location and ...


Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Genda Chen Aug 2018

Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Genda Chen

INSPIRE-UTC Annual Meetings

A typical human eye will respond to wavelengths from approximately 400 to 700 nm. A hyperspectral camera can extend the wavelength to as high as 2500 nm. This extension will allow engineers to find objects, identify materials, and detect processes on structural surface, which cannot be done with visual inspection.

This project aims to develop an open-source catalogue of concrete and steel surfaces and their spectral/spatial features (discoloration, characteristic wavelength, roughness, texture, shape, etc.), extract spatial/spectral features of hyperspectral images, and develop/train a multi-class classification or regression classifier through machine learnings (supervised and/or semi-supervised), and validate ...


3d Microwave Camera For Concrete Delamination And Steel Corrosion Detection, R. Zoughi Aug 2018

3d Microwave Camera For Concrete Delamination And Steel Corrosion Detection, R. Zoughi

INSPIRE-UTC Annual Meetings

Corrosion of embedded steel reinforcement in concrete leads to concrete cracking and delamination, followed by increased salt and moisture permeation and further damage. Invisibility of the embedded rebar in combination with physical inaccessibility in elevated bridges presents a challenge in the assessment of RC bridge elements. Wideband (3D) microwave synthetic aperture radar (SAR) imaging techniques that can be integrated into a UAV offer a practical solution to overcome this challenge.

This project aims to develop and optimize a 3D microwave camera for bridge inspection on a UAV platform, quantify its performance for steel corrosion evaluation and concrete delamination detection in ...


Battery-Free Antenna Sensors For Strain And Crack Monitoring Of Bridge Structures, Yang Wang Aug 2018

Battery-Free Antenna Sensors For Strain And Crack Monitoring Of Bridge Structures, Yang Wang

INSPIRE-UTC Annual Meetings

Fatigue cracks need to be monitored in fatigue critical elements. Previous research by the PI produced a radiofrequency identification (RFID) sensor prototype that can accurately measure tens of micro-strains in laboratory. The antenna sensor was made on a glass microfiber-reinforced polymer substrate. Although accurate for strain measurement and detection of fatigue cracks, the sensor performs less satisfactorily in field conditions since the substrate material (RT/duroid® 5880) is susceptible to thermal effect. In addition, a wireless interrogation distance by a general-purpose commercial RFID reader is limited to the order of meter, which is not desirable with the operation of a ...


Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, Genda Chen Aug 2018

Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, Genda Chen

INSPIRE-UTC Annual Meetings

Foundation scour is the main cause of bridge collapses in the U.S. In 2011, the principal investigator (PI) proposed smart rocks with embedded magnets for bridge scour monitoring. Once deployed around a bridge pier, smart rocks as field agents offer mission-critical information about the maximum depth of a scour hole developed around the bridge foundation – the key parameter that is used to assess foundation stability in engineering design and retrofit. Smart rocks have recently been deployed and tested at three bridge sites in California and Missouri. With multiple measurements, they can be located with an accuracy of 0.5 ...


Effect Of Differences In The Primary Structure Of The A-Chain On The Aggregation Of Insulin Fragments, Paul P. Nakka, Ke Li, Daniel Forciniti Aug 2018

Effect Of Differences In The Primary Structure Of The A-Chain On The Aggregation Of Insulin Fragments, Paul P. Nakka, Ke Li, Daniel Forciniti

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bovine and human insulin have similar primary structures. In this article, the region of the insulin A-chain of bovine and human insulin where the amino acid composition is different was studied. Bovine insulin fragment (BIF) and human insulin fragment (HIF) were synthesized in solid-phase peptide synthesis. The effects of pH, temperature, urea, ionic strength, and stirring on the formation of fibrils were studied using a fractional factorial resolution III experimental design. Fibrillation was monitored by fluorescence and infrared spectroscopy and optical microscopy. Both fragments formed fibrils at pH 1.6 and a temperature of 60 °C. The lag time and ...


Significant Improvement In Tio₂ Photocatalytic Activity Through Controllable Zro₂ Deposition, Xiaofeng Wang, Rajankumar L. Patel, Xinhua Liang Jul 2018

Significant Improvement In Tio₂ Photocatalytic Activity Through Controllable Zro₂ Deposition, Xiaofeng Wang, Rajankumar L. Patel, Xinhua Liang

Chemical and Biochemical Engineering Faculty Research & Creative Works

ZrO2 was deposited on anatase TiO2 nanoparticles using 5-80 cycles of atomic layer deposition (ALD). The photocatalytic activity of all samples was evaluated based on the degradation of methylene blue (MB) solution under UV light. The TiO2 sample with 45 cycles of ZrO2 deposition (45c-Zr/TiO2, 1.1 wt% ZrO2) was proved to be the most efficient catalyst with a degradation kinetic constant 10 times larger than that of the pure TiO2 sample. All samples were characterized using inductively coupled plasma atomic emission spectroscopy (ICP-AES), nitrogen adsorption-desorption, X-ray diffraction (XRD), transmission electron microscopy ...


Repeated Loading Model For Elastic-Plastic Contact Of Geomaterial, Jian Wang, Qimin Li, Changwei Yang, Caizhi Zhou Jul 2018

Repeated Loading Model For Elastic-Plastic Contact Of Geomaterial, Jian Wang, Qimin Li, Changwei Yang, Caizhi Zhou

Materials Science and Engineering Faculty Research & Creative Works

A new nonlinear hysteretic model with considering the loading, unloading, and reloading processes is developed based on Drucker—Prager yield criterion and finite-element analysis. This model can be used for multiple repeated elastic—plastic normal direction contact problems between two identical spherical geomaterials. After examining the influence of material properties, strain hardening, and loading histories, we found that the hysteretic phenomena (represented by residual displacement and plastic work) become weak after the first cycle, and the subsequent cycles step into elastic shakedown state eventually. A critical number of cycles can be used to estimate the state of ratchetting, plastic shakedown ...


A Nonlinear Crack Model For Concrete Structure Based On An Extended Scaled Boundary Finite Element Method, Jian-Bo Li, Xin Gao, Xing-An Fu, Chenglin Wu, Gao Lin Jul 2018

A Nonlinear Crack Model For Concrete Structure Based On An Extended Scaled Boundary Finite Element Method, Jian-Bo Li, Xin Gao, Xing-An Fu, Chenglin Wu, Gao Lin

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Fracture mechanics is one of the most important approaches to structural safety analysis. Modeling the fracture process zone (FPZ) is critical to understand the nonlinear cracking behavior of heterogeneous quasi-brittle materials such as concrete. In this work, a nonlinear extended scaled boundary finite element method (X-SBFEM) was developed incorporating the cohesive fracture behavior of concrete. This newly developed model consists of an iterative procedure to accurately model the traction distribution within the FPZ accounting for the cohesive interactions between crack surfaces. Numerical validations were conducted on both of the concrete beam and dam structures with various loading conditions. The results ...


Climbing Robots For Steel Bridge Inspection And Evaluation, Hung La Jun 2018

Climbing Robots For Steel Bridge Inspection And Evaluation, Hung La

Archived Webinars

Steel structures and steel bridges, constituting a major part in civil infrastructure, require adequate maintenance and health monitoring. In the U.S., more than 50,000 steel bridges are either deficient or functionally obsolete, which likely presents a growing threat to people's safety. The collapse of numerous bridges recorded over the past 16 years has shown significant impact on the safety of all travelers.

In this presentation, the design and implementation of two different climbing robots for steel structure inspection are reported. Based on the magnetic wheel design, the robot can climb on different steel surface structures (i.e ...


Tag Ownership Transfer In Radio Frequency Identification Systems: A Survey Of Existing Protocols And Open Challenges, Eyad Taqieddin, Hiba Al-Dahoud, Haifeng Niu, Jagannathan Sarangapani Jun 2018

Tag Ownership Transfer In Radio Frequency Identification Systems: A Survey Of Existing Protocols And Open Challenges, Eyad Taqieddin, Hiba Al-Dahoud, Haifeng Niu, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Radio frequency identification (RFID) is a modern approach to identify and track several assets at once in a supply chain environment. In many RFID applications, tagged items are frequently transferred from one owner to another. Thus, there is a need for secure ownership transfer (OT) protocols that can perform the transfer while, at the same time, protect the privacy of owners. Several protocols have been proposed in an attempt to fulfill this requirement. In this paper, we provide a comprehensive and systematic review of the RFID OT protocols that appeared over the years of 2005-2018. In addition, we compare these ...