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Full-Text Articles in Engineering
An Assessment Of The Audio Codec Performance In Voice Over Wlan (Vowlan) Systems, Miroslaw Narbutt, Mark Davis
An Assessment Of The Audio Codec Performance In Voice Over Wlan (Vowlan) Systems, Miroslaw Narbutt, Mark Davis
Conference papers
In this paper we present results of experimental investigation into the performance of three audio codecs (ITU-T G.711, G.723.1 and G.729A) under varying load conditions on a Voice over WLAN system utilizing the IEEE 802.11b wireless LAN standard. The analysis is based upon a new technique for estimating user satisfaction of speech quality calculated from packet delay and packet loss/late measurements. We also demonstrate the importance of the de-jitter buffer playout scheme for insuring speech quality. From our results we conclude that the use of the G.711 audio codec in conjunction with the new adaptive playout scheme gives the highest …
Pavement/Sub-Grade Condition Assessment I-65 Approximate Milepost 97.5 To 102.5 (Transition From Asphalt To Concrete) To (Ky 313 Overpass), Brad Rister, Clark Graves
Pavement/Sub-Grade Condition Assessment I-65 Approximate Milepost 97.5 To 102.5 (Transition From Asphalt To Concrete) To (Ky 313 Overpass), Brad Rister, Clark Graves
Kentucky Transportation Center Research Report
This report summarizes the condition assessment of the pavement structure on I-65 between 97.5 to 102.5. Three types of equipment were used to evaluate the present condition of the pavement: falling weight deflectormeter, ground penetrating radar, and coring machine, Results indicated that durability of the existing concrete surface appears to be the most detrimental problem encountered in this survey. Load-transfer across transverse joint appear to be in acceptable ranges. Limited areas were identified to have less than four inches of D.G.A. beneath the concrete pavement. These areas have also been experiencing the most differential settlement. In addition several areas are …
Integrated Field Measurements And Track Simulations For Condition Assessment Of Railway Track, Sakdirat Kaewunruen, Alexander Remennikov
Integrated Field Measurements And Track Simulations For Condition Assessment Of Railway Track, Sakdirat Kaewunruen, Alexander Remennikov
Faculty of Engineering - Papers (Archive)
Assessment of condition of railway track is crucial for track design, repair and effective maintenance operations. In-field dynamic testing in combination with track modelling represents an efficient strategy for identification of the current condition of railway track structure and its components. This paper presents an integrated approach combining field measurements, experimental modal analysis and finite element modelling to evaluate the dynamic parameters of the in-situ railway track components. Based on the discrete support model, a two-degree-of-freedom (2DOF) dynamic model of railway track is analysed in order to extract the modal properties of the track components from the field dynamic testing …
Human Risk Assessment Of Organic Contaminants In Reclaimed Wastewater Used For Irrigation, S. Weber, Stuart Khan, J. Hollender
Human Risk Assessment Of Organic Contaminants In Reclaimed Wastewater Used For Irrigation, S. Weber, Stuart Khan, J. Hollender
Faculty of Engineering - Papers (Archive)
Current water quality guidelines for reclaimed wastewater have predominantly addressed risks associated with the presence of microbial organisms. Comparatively, chemical parameters have been largely overlooked or inadequately considered. Acceptable levels of chemical parameters will be dependant on the proposed reuse applications for the water and, in many cases, site-specific factors such as the degree of dilution with water from other sources. However, some general principals for the determination of acceptable levels of chemical contaminants in reclaimed water may be applied universally. This study describes a general risk-assessment approach to the determination of acceptable contaminant concentrations. It provides some analysis of …
Experimental And Numerical Methodology Assessment Of Load Transfer Capacity Of Bolts, Najdat I. Aziz, Hossein Jalalifar
Experimental And Numerical Methodology Assessment Of Load Transfer Capacity Of Bolts, Najdat I. Aziz, Hossein Jalalifar
Faculty of Engineering - Papers (Archive)
In Australia, the common method of laboratory testing of bolt for load transfer capacity determination is by short encapsulation push testing. Some concerns are raised about the validity of the test methodology, as the method does not reflect on the actual load transfer characteristics of bolt in real field situation. Thus, laboratory testes were carried out to examine the load transfer mechanisms of bolts in both the push and pull conditions. Tests were conducted by shearing a short resin encapsulated bolt out of a cylindrical steel sleeve. Three types of bolts with different surface profile configurations were tested. The study …