856 research outputs found
Editorial
Ushus Journal of Business Management wishes all its readers a very happy new year. In this final issue of 2015, the journal carries four research articles and two case studies in marketing.
The Indian banking system consists of 26 public sector banks, 25 private sector banks, 43 foreign banks, 56 regional rural banks, 1,589 urban cooperative banks and 93,550 rural cooperative banks
Experimental Evaluation of Foam-Void Double-Tees
Gross vehicular weight restrictions limit the shipping of typical pre-stressed concrete double-tees (DT) for parking decks to one member per trip. The objective of this study is to reduce the self-weight of these members to facilitate two-at-a-time shipping, and thus enable lower shipping costs and reduced environmental footprint. In this research, two 35 foot-long DT members were fabricated and tested to study strategies for reducing self-weight. Foam boards were placed inside the stems of the DT members to produce foam-void double-tees (FVDT). One inch and two inch-thick foam boards were used along with normal and semi-light weight concretes. The two FVDT members were cut length-wise through the top flanges to create four unique single-tee specimens, which were then load tested to evaluate structural capacity and behavior. This thesis discusses the experimental setup and results of flexural testing and shear testing. The test results demonstrated that the presence of foam boards had negligible effect on flexural performance; each of the foam-void specimens supported an experimental moment that was greater than the calculated nominal moment capacity and the shear capacity was more than that expected demand for a typical parking garage DT. Furthermore, cracking near the edges of the foam voids was not an issue under service or higher loads
Crack Control and Bond Performance of Alternative Coated Reinforcements in Concrete
Concrete cracking in structures is a ubiquitous problem which can lead to the deterioration of the structure. Other than affecting the strength aspect of a structure, cracking impacts the serviceability criteria as well. Although cracking phenomenon in any structure is highly inevitable, it has to be minimized in order to maintain a structure’s life effectively. Cracking in reinforced concrete structures is related to the bond strength developed between the bar and the concrete. It also depends on an ability of the bar to resist the stresses due to shrinkage to minimize the crack. Another important aspect is the resistance offered by the reinforcement to minimize the residual crack width after withdrawal of high loads beyond or near the yielding capacity. All these parameters were considered and have been studied as a part of this dissertation through experimental testing.
The variables used in the tests are the alternative coated reinforcements like textured epoxy, hot dipped galvanized, and continuously galvanized reinforcements. Variables also included uncoated (black) and conventional epoxy (smooth epoxy) reinforcements which have been used in structure for many decades. Considering all the tests conducted, an overview analysis was done to determine the best performing bar coating for crack control and rebar-concrete bond. The results show that textured epoxy bars were the best performer in 47% of tests. On the other hand, smooth epoxy bars were the worst performer in 47% of tests. Uncoated, hot dipped galvanized, and continuously galvanized bars were typically in-between textured and smooth epoxy bars in their performance.
This dissertation also analytically evaluated the bond mechanics associated with the variable bar coatings considered in the experimental program. Two different models of bar force variation at and around a crack location were considered to calculate the length over which forces transfer between the bar and concrete. The calculated lengths were compared to data from an associated peer study. It is inferred from the results that a small portion of a bar is de-bonded adjacent to the cracks and the forces transfer gradually at locations beyond the debonding. This inference applies to all the bar coatings in the data except the continuously galvanized reinforcement. Conclusions for continuously galvanized reinforcement could not be made because of limited and randomness in the data
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AnveShA : automatic search and monitoring agent for Craigslist
textThe popularity of Craigslist has enabled users worldwide to find almost any product at prices significantly less than retail prices or market-prices. Craigslist has thus enabled lot of resellers to enter the market and has created a huge market for used/pre-owned products. The key to find products at prices less than their market-prices is to find the right classified and act immediately before other users. Craigslist search agents, with ability to search classifieds, that run on mobile/handheld devices are increasing in popularity with ubiquitous internet connectivity, convenience and speed. AnveShA is an automatic search and monitoring agent for craigslist that has been developed for Android platforms. AnveShA provides easy access and a rich feature-set that is not available in the state-of-the-art craigslist search applications available on the Android market. AnveShA has been developed to provide the user a rapid and intelligent search agent that can proactively search and monitor classifieds for desired products, contact sellers and increase the chances of obtaining the desired product at the best possible price. To achieve this, AnveShA has many unique features like the ability to schedule and execute automatic searches, search classifieds based on geographical location, automatically respond to classifieds, store price history for classifieds, get comparative prices from other retail/shopping websites, store favorite classifieds/reminder lists and predict the offer price based on a number of parameters. With such unique features, AnveSha assists users or resellers to find desired products at the best possible prices on Craigslist and hence have a significant advantage over the competition.Electrical and Computer Engineerin
Modeling Energy Expenditure and Recovery in Cycling
The power-duration relationship, comprised of the parameters Critical power (CP) and work capacity (ϒ), has been used to model energy expenditure in cycling. For modeling recovery, the W\u27bal model has been used but lacks validation. Additionally, existing literature has not focused on quantifying or estimating the inherent trial-to-trial variability at the subject level, called the intra-individual variability (IIV), of CP and ϒ, posing challenges in modeling and optimization of performance. Thus, the objectives of this research are (i) to establish a method to quantify the IIV of CP and ϒ as determined from the 3-minute all-out test (3MT), (ii) to develop a testing protocol to understand expenditure and recovery of power and ϒ, (iii) to establish ϒ recovery profiles in terms of recovery power (Prec) and recovery duration (trec), and (iv) to present a case of cycling performance optimization using the energy management system based on athlete-specific models. Competitive amateur cyclists participated in two cycle ergometer studies: (i) repeatability of 3MTs to quantify IIV and (ii) intermittent cycling, in the laboratory to establish ϒ recovery profiles. The studies included an incremental ramp test to determine gas exchange threshold (GET), two or four 3MTs to determine CP and ϒ, and nine intermittent cycling tests to understand recovery of ϒ. From the repeated 3MT study, a new method was proposed to compare any two pairs of the 3MT at the individual level and estimate the IIVs associated with CP and ϒ. In the second study, a statistically significant two-way interaction effect between Prec and trec on ϒ recovery was observed followed by simple main effects seen only with respect to Prec at each trec. This indicates that Prec has a greater influence on the recovery of ϒ in a recovery interval lasting 2-15 minutes that follows a semi-exhaustive exertion interval above CP. The overestimation of the actual ϒ-balance at the end of the recovery interval by the W\u27bal models highlights the need for athlete-specific recovery parameters or models. Finally, the optimization tests conducted with one subject provide encouraging signs for the use of individualized recovery models in real-time in-situ performance optimization
Modeling the behavior of anaerobic work capacity in cycling
Models of fatigue are based on physiological parameters such as Critical Power (CP) and Anaerobic Work Capacity (AWC). CP is a theoretical power that can be maintained indefinitely and AWC is a finite anaerobic energy reservoir for efforts above CP. There is an increasing interest in developing mathematical models of energy expenditure and recovery for athletic training and performance. Recently, researchers have developed formal mathematical models that aid in better management of performance. Most available models have originated from cycle ergometer tests due to the ease of measuring power in cycling. The objectives of this research are (i) to develop a testing protocol to understand expenditure and recovery of AWC in cycling, (ii) to establish AWC recovery profiles in terms of recovery powers and durations, and (iii) to combine AWC recovery with expenditure for energy management in cycling. Nine recreational cyclists performed a study which involved a VO2max ramp test to determine gas exchange threshold (GET), a 3-min all-out intensity test (3MT) to determine CP and AWC, and 9 intermittent cycling tests to understand recovery of AWC. Three cyclists completed all tests resulting in a complete profile of the AWC recovery. The results indicate that AWC recovered during recovery decreases with increasing recovery powers. No generic trends were observed in AWC recovery with respect to recovery durations. In addition, the tests indicate the need for individualized models owing to the inherent within-subject variability (WSV) associated with CP and AWC. Quantifying this WSV will aid in accurately modelling and optimizing performance
Control of thermoforming process parameters to manufacture surfaces with pin-based tooling
Many manufacturing processes used to mass produce parts rely on expensive and time consuming tooling. These processes include sheet metal forming, injection molding, casting, and thermoforming. The time invested in design and development of tooling can be justified for high-production volumes. However, for low-volume production and customized products, the tooling investment cannot be amortized. Flexible tooling has been developed to address the needs of smaller production volumes. Reconfigurable pin tooling is an example of flexible tooling that relies on a matrix of adjustable-height pins to produce approximate surfaces. A key challenge in pin-based tooling is achieving accurate high quality surfaces due to the undulations caused by the pins in mimicking the desired shape. This research studies the effects of process parameters on surface quality. A testbed pin tool and thermoformer are fabricated to support this research. The pin tool comprises of a 10 by 10 matrix of square pins. Each pin measures 0.25 inch by 0.25 inch by 2.5 inches and is actuated manually using screws. Twenty-one exploratory and thirty-two shape specific experiments were conducted with 12 inch by 12 inch polystyrene sheets to check the feasibility of producing undulation-free surfaces. The parameters that influence the quality of the surfaces are heating time, sheet thickness, and sheet to fixture distance. Surface quality is measured by conformance with respect to the tool and the intensity of undulations. The surface-reproducibility and the measurement-repeatability errors were determined to be ±0.0045 mm and ±0.00027 mm respectively. The surface quality can be improved by reducing intensity of undulations by controlling the process parameters. The quality of thermoformed surfaces using the pin tool is a function of heating time and the intended shape
Flow unsteadiness effects on boundary layers
The development of boundary layers at high subsonic speeds in the presence of either mass flux fluctuations or acoustic disturbances (the two most important parameters in the unsteadiness environment affecting the aerodynamics of a flight vehicle) was investigated. A high quality database for generating detailed information concerning free-stream flow unsteadiness effects on boundary layer growth and transition in high subsonic and transonic speeds is described. The database will be generated with a two-pronged approach: (1) from a detailed review of existing literature on research and wind tunnel calibration database, and (2) from detailed tests in the Boundary Layer Apparatus for Subsonic and Transonic flow Affected by Noise Environment (BLASTANE). Special instrumentation, including hot wire anemometry, the buried wire gage technique, and laser velocimetry were used to obtain skin friction and turbulent shear stress data along the entire boundary layer for various free stream noise levels, turbulence content, and pressure gradients. This database will be useful for improving the correction methodology of applying wind tunnel test data to flight predictions and will be helpful for making improvements in turbulence modeling laws
Structural and Optical Properties of Cu2ZnSnS4 Nanoparticles for Solar Cell Applications
The Cu2ZnSnS4 (CZTS) nanoparticles were successfully synthesized by Chemical co-precipitation method with different synthesis temperatures. The synthesized nanoparticles were characterized by X-ray diffraction, Raman Spectroscopy, Scanning electron microscopy, Energy dispersive spectroscopy and UV-VIS-NIR spectrophotometer. XRD and Raman studies revealed that the CZTS nanoparticles exhibited Kesterite Structure with preferential orientation along the (112) direction. The CZTS nanoparticles synthesized at a temperature 150 C exhibited near stoichiometry. On further increasing the synthesis temperature sulphur composition was decreased due to volatile nature of the sulphur. The synthesized nanopar-ticles exhibited an optimum band gap of 1.4 eV.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3194
Trust Factors’ Influence on Consumers’ Purchase Intention When Browsing Unfamiliar E-Commerce Websites
This research aimed to look into the importance of trustfactors and consumer purchase intentions to buy fromunfamiliar websites. The new entrants in the online ecommerce space need to attract customers to its websites.The study enables the retailers to understand these trustfactors which also influence the consumers’ purchaseintention on their websites. A survey was conductedamong the users of new or unfamiliar websites. Therewere major five trust factors considered for this study andan attempt had been made to establish a relationshipbetween these trust factors and the Purchase Intention ofconsumers from unfamiliar websites. Multiple linearregression techniques were used. The major outcome ofthe study was that the trust factors, secured transactions,website design, associated offers, E-retailers' contactinformation had a significant influence on the PurchaseIntention of consumers
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