Testing and simulation of extruded polystyrene foam at low to moderate strain rates

This paper presents a study into the behaviour of extruded polystyrene foam at low strain rates. The foam is being studied in order assess its potential for use as part of a new innovative design of portable road safety barrier the aim to consume less water and reduce rates of serious injury. The foam was tested at a range of low strain rates, with the stress and strain behaviour of the foam specimens being recorded. The energy absorption capabilities of the foam were assessed as well as the response of the foam to multiple loadings. The experimental data was then used to create a material model of the foam for use in the explicit finite element solver LS-DYNA. Simulations were carried out using the material model which showed excellent correlation between the numerical material model and the experimental data

Preliminary characterisation of the surface of cartilage following exposure to saturated and unsaturated synthetic lips

Articular cartilage is covered by a microscopic structure known as surface amorphous layer. This surface structure is often the first victim of attack during cartilage degeneration, thereby resulting in a gross impairment in cartilage function such as lubrication and load bearing. We hypothesize that incubation of degraded cartilage in solutions of different species of synthetic surface active phospholipids (saturated and unsaturated species) can remodel this lost surface structure. To test this hypothesis, the structural configuration of the surface of articular cartilage was studied and characterised with the lipid filled surface amorphous layer intact using the AFM. The results were then compared with those obtained following a systematic removal (delipidization) and replacement (relipidization) of this layer. Our results show that the unsaturated surfactant partially restored the lost surface amorphous layer while the saturated surfactant specie settled on the surface due to its poor solubility in aqueous solution

Precast prestressed bridge approach slab : cost effective designs

Title from PDF of title page (University of Missouri--Columbia, viewed on September 12, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Vellore S. GopalaratnamIncludes bibliographical references.M.S. University of Missouri--Columbia 2012."May 2012"Bridge approach slabs (BAS) are transition slabs used to connect the roadway with the bridge. Among the various problems bridge approach slabs experience, differential settlement is the found to be the major cause leading to approach slab distress. The two suggested alternatives are also effective for rapid replacement/repair operations on bridge approach slabs. A life cycle analysis (LCCA) was completed to study comparative costs for urban and rural traffic patterns and to investigate the economic effectiveness of the precast prestressed slab designs. The MoDOT BAS design along with another design alternative called BAS incorporating elastic support (BAS-ES) were included in the LCCA procedure to study the effectiveness of the precast prestressed alternatives. When present value of total costs are considered, the Fully Precast Prestressed - BAS design is the most cost-effective when AADT counts are high, such as with urban traffic demands

Remote sensing of atmospheric winds using a coherent, CW lidar and speckle-turbulence interaction

Speckle turbulence interaction has the potential for allowing single ended remote sensing of the path averaged vector crosswind in a plane perpendicular to the line of sight to a target. If a laser transmitter is used to illuminate a target, the resultant speckle field generated by the target is randomly perturbed by the atmospheric turbulence as it propagates back to the location of the transmitter-receiver. When a cross wind is present, this scintillation pattern will move with time across the receiver. A continuous wave (cw) laser transmitter of modest power level in conjunction with optical heterodyne detection was used to exploit the speckel turbulence interaction and measure the crosswind. The use of a cw transmitter at 10.6 microns and optical heterodyne detection has many advantages over direct detection and a double pulsed source in the visible or near infrared. These advantages include the availability of compact, reliable and inexpensive transmitters, better penetration of smoke, dust and fog; stable output power; low beam pointing jitter; and considerably reduced complexity in the receiver electronics

ORGANIZE EVENTS MOBILE APPLICATION

In a big organization there are many events organized every day. To know about the events, we typically need to check an events page, rely on flyers or on distributed pamphlets or through word of mouth. To register for an event a user now a days typically does this online which involves inputting user details. At the event, the user either signs a sheet of paper or enters credentials in a web page loaded on a tablet or other electronic device. Typically, this is a time-consuming process with many redundancies like entering user details every time the user wants to register for a new event and re-entering the details at the event. This project designs a system that eliminates these redundancies and improves event management

Simplified Approach to Assess the Capacity Credit of Wind Electric Conversion Systems

Wind electric conversion has become one of the most promising technologies to address the various energy issues facing the United States. National initiatives such as "20% electricity from wind by 2030" and grand plans to replace some of the gas-fired electric generation by wind so that the saved gas can be used in compressed form to power automobiles leading to a decrease in importation of petroleum are manifestations of the progress made just in the past decade. Among the many issues for consideration as the penetration of wind generated electric power into conventional power systems increases, quantification of "energy credit" and "capacity credit" ranks high because of its direct economic impact. This study considers the issue of capacity credit and its assessment. Capacity credit can be assessed by detailed simulation using iterative or non-iterative methods. Considerable work has been done in these areas. However, these techniques are cumbersome and require considerable amount of data and information. The simplified approach presented in this study employs an effective forced outage rate for a wind generator and uses the classic loss of load probability calculations to estimate/assess the capacity credit. The result is a good estimate for capacity credit and it can be followed by detailed calculations as needed. Results of sensitivity analyses are presented to study the impact of penetration levels, amount of spinning reserve, wind parameters and wind turbine output characteristics.School of Electrical & Computer Engineerin

A 3D measurement and computerized meshing study to promote bus ridership among people using powered mobility aids

People who use powered mobility aids such as wheelchairs and scooters need and want to use public transport. Buses are the most affordable and efficient form of public transport, capable of connecting people across local communities. However, with curbside rather than platform boarding and internal space limitations, buses also present many accessibility challenges for people using mobility aids during ingress, egress, and interior maneuverability. In Australia, people using mobility aids board low floor buses that are required to comply with the national bus accessibility standard, using the front doors. A new standard was recently created to provide a Blue Label identification for powered mobility aids suitable to access public transport. The accuracy of this standard to identify mobility aids suitable to use on buses has not been verified. This research used a world-first methodology that included 3-Dimensional (3D) scanning of 35 mobility aids and 21 buses. The resulting 735 scan combinations were efficiently meshed using Meshlab, an open-source software. The research demonstrated that (i) although none of the buses were compliant with the relevant standard in 3D, many could still facilitate the boarding of a variety of mobility aids, and (ii) the Blue Label, while a valuable guide, did not accurately identifying all mobility aids that would and would not be able to board buses. This research has shortlisted nine mobility aids that can be recommended to consumers as being able to fit all the full-size buses tested. The dimensions of mobility aids that appear to enable access on most buses were also identified for consumers to consider when purchasing a mobility aid. The novel 3D meshing methodology used in this research also revealed that most collision points between mobility aids and buses occur in the curved-corridor entry of the buses. To minimize this entry problem, future bus boarding designs should consider the option of double-door entry/exit in the middle of the bus, which is common in many other countries. Adoption of this strategy would mitigate some of the challenges that people using mobility aids encounter when accessing buses, thereby increasing public transport ridership among this group. © Copyright © 2020 Unsworth, Chua and Gudimetla

An Experiment on Bare-Metal BigData Provisioning

Many BigData customers use on-demand platforms in the cloud, where they can get a dedicated virtual cluster in a couple of minutes and pay only for the time they use. Increasingly, there is a demand for bare-metal bigdata solutions for applications that cannot tolerate the unpredictability and performance degradation of virtualized systems. Existing bare-metal solutions can introduce delays of 10s of minutes to provision a cluster by installing operating systems and applications on the local disks of servers. This has motivated recent research developing sophisticated mechanisms to optimize this installation. These approaches assume that using network mounted boot disks incur unacceptable run-time overhead. Our analysis suggest that while this assumption is true for application data, it is incorrect for operating systems and applications, and network mounting the boot disk and applications result in negligible run-time impact while leading to faster provisioning time.This research was supported in part by the MassTech Collaborative Research Matching Grant Program, NSF awards 1347525 and 1414119 and several commercial partners of the Massachusetts Open Cloud who may be found at http://www.massopencloud.or

A Secure Protocol for M-commerce Secure SMS Mobile Payment

The worldwide utilization of the Internet has profoundly supplied the development of e-commerce. Technological advancement in mobile phones (e.g. Mobile phones) has likewise added to doing e-commerce by means of mobile phones (m-business). Mcommerce includes the utilization of mobile phones, for example, mobile phones in doing electronic exchanges. Applications in this area range from ordinary data utilization to high security money related electronic exchanges. Much the same as e-commerce, the security of m-business applications is basic, particularly when it includes applications that arrangement with client touchy information, In the usage, the purchaser utilizes the program to shop online of course, at the checkout he is sent to the versatile application gave and secured by the bank. The gatherings imparts through three distinctive channels (VPN burrowing, SMS informing and HTTPS) to improve the security. This convention guarantees that the purchaser basic data is never ignored the web to have the capacity to buy and in the meantime the scanning knowledge has little interference. Additionally it presents minimal overhead on the vendor and the banks to have the capacity to give such administration. To ensure the convention acts as expected, an android application was made that speaks with web servers speaking to the purchaser bank, the shipper site and vendor bank. All interchanges between the application and the purchaser bank were through VPN and SMS

Adaptive Optics Performance Over Long Horizontal Paths: Aperture Effects in Multi-Conjugate Adaptive Optical Systems

We analyze various scenarios of the aperture effects in adaptive optical receiver-type systems when inhomogeneities of the wave propagation medium are distributed over long horizontal propagation path, or localized in a few thin layers remotely located from the receiver telescope pupil. Phase aberration compensation is performed using closed-loop control architectures based on phase conjugation and decoupled stochastic parallel gradient descent (DSPGD) control algorithms. Both receiver system aperture diffraction effects and the impact of wave-front corrector position on phase aberration compensation efficiency are analyzed for adaptive systems with single or multiple wave-front correctors