189 research outputs found

    Chemical Composition of the Temporal Gland Secretion of an Asian Elephant (Elephas maximus)

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    The non-volatile chemical constituents of a temporal gland secretion of a male Asian elephant are reported for the first time, and they seem to be different, in part, from those of the African elephant

    Sight Distance Standards Based On Observational Data Risk Evaluation Of Passing

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    The paper presents an application of a reliability analysis for evaluating the risk associated with passing sight distance (PSD) standards in terms of the expected probability of noncompliance. Calculation of PSD is required to determine where drivers can safely execute passing maneuvers. Traditional PSD standards are based on deterministic, theoretical models, which are calibrated with conservative percentile values for uncertain design inputs to account for uncertainty. The PSD standards do not provide information about the risk of deviation from them. Reliability analysis is a technique that is based on limit state design and that accounts for the propagation of variability from input random parameters to the design outputs. A total of 1,098 passing maneuvers were observed on several two-lane highways in Spain; two data collection methodologies were used: external observations and an instrumented vehicle. The most significant factors affecting PSD were impeding-vehicle speed, passing-vehicle acceleration, and head-ways between impeding and passing vehicles. A uniform acceleration model described the passing-vehicle trajectory. The characterized input parameters and the passing model were used to perform a reliability analysis. The results showed the probability of noncompliance in different scenarios, defined as the proportion of cases in which the required PSD would exceed the available sight distance. American and Spanish PSD standards were evaluated. Geometric design standards presented a probability of noncompliance of about 0.15, whereas some marking standards had a probability of noncompliance exceeding 0.85. These standards may be associated with higher risk levels if they are followed by drivers. As well, PSD risk levels were not consistent for different design speeds, since they underestimated operating speed at some locationsThis paper was developed as a result of a mobility study at the University of British Columbia funded by the Erasmus Mundus Program of the European Commission under the Transatlantic Partnership for Excellence in Engineering project. The authors thank the Spanish Ministry of Economy and Competitiveness, which subsidized the research project, and the Spanish Directorate General of Traffic, Spanish Ministry of Public Works, Valencia Regional Department of Transport, and Valencia province road department for their collaboration during the field study.Llorca Garcia, C.; Moreno Chou, AT.; Sayed, T.; GarcĂ­a GarcĂ­a, A. (2014). Sight Distance Standards Based On Observational Data Risk Evaluation Of Passing. Transportation research record. 2404:18-26. doi:10.3141/2404-03S18262404Ismail, K., & Sayed, T. (2009). Risk-based framework for accommodating uncertainty in highway geometric design. Canadian Journal of Civil Engineering, 36(5), 743-753. doi:10.1139/l08-146Ismail, K., & Sayed, T. (2010). Risk-Based Highway Design. Transportation Research Record: Journal of the Transportation Research Board, 2195(1), 3-13. doi:10.3141/2195-01Richl, L., & Sayed, T. (2006). Evaluating the Safety Risk of Narrow Medians Using Reliability Analysis. Journal of Transportation Engineering, 132(5), 366-375. doi:10.1061/(asce)0733-947x(2006)132:5(366)Harwood, D. W., Gilmore, D. K., & Richard, K. R. (2010). Criteria for Passing Sight Distance for Roadway Design and Marking. Transportation Research Record: Journal of the Transportation Research Board, 2195(1), 36-46. doi:10.3141/2195-05Wang, Y., & Cartmell, M. P. (1998). New Model for Passing Sight Distance on Two-Lane Highways. Journal of Transportation Engineering, 124(6), 536-545. doi:10.1061/(asce)0733-947x(1998)124:6(536)Polus, A., Livneh, M., & Frischer, B. (2000). Evaluation of the Passing Process on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 53-60. doi:10.3141/1701-07Llorca, C., & GarcĂ­a, A. (2011). Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data. Transportation Research Record: Journal of the Transportation Research Board, 2262(1), 42-51. doi:10.3141/2262-05Carlson, P., Miles, J., & Johnson, P. (2006). Daytime High-Speed Passing Maneuvers Observed on Rural Two-Lane, Two-Way Highway: Findings and Implications. Transportation Research Record: Journal of the Transportation Research Board, 1961, 9-15. doi:10.3141/1961-02Llorca, C., Moreno, A. T., GarcĂ­a, A., & PĂ©rez-Zuriaga, A. M. (2013). Daytime and Nighttime Passing Maneuvers on a Two-Lane Rural Road in Spain. Transportation Research Record: Journal of the Transportation Research Board, 2358(1), 3-11. doi:10.3141/2358-01Easa, S. M. (1993). Reliability‐Based Design of Intergreen Interval at Traffic Signals. Journal of Transportation Engineering, 119(2), 255-271. doi:10.1061/(asce)0733-947x(1993)119:2(255)Selvanathan, E. A., & Selvanathan, S. (1994). The demand for transport and communication in the United Kingdom and Australia. Transportation Research Part B: Methodological, 28(1), 1-9. doi:10.1016/0191-2615(94)90027-2Easa, S. M. (2000). Reliability Approach to Intersection Sight Distance Design. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 42-52. doi:10.3141/1701-06Ibrahim, S. E.-B., & Sayed, T. (2011). Developing safety performance functions incorporating reliability-based risk measures. Accident Analysis & Prevention, 43(6), 2153-2159. doi:10.1016/j.aap.2011.06.006Khoury, J. E., & Hobeika, A. G. (2007). Assessing the Risk in the Design of Passing Sight Distances. Journal of Transportation Engineering, 133(6), 370-377. doi:10.1061/(asce)0733-947x(2007)133:6(370)Khoury, J. E., & Hobeika, A. G. (2012). Integrated Stochastic Approach for Risk and Service Estimation: Passing Sight Distance Application. Journal of Transportation Engineering, 138(5), 571-579. doi:10.1061/(asce)te.1943-5436.0000366Kim, S., & Choi, J. (2013). Effects of preceding geometric conditions on operating speed consistency of multilane highways. Canadian Journal of Civil Engineering, 40(6), 528-536. doi:10.1139/cjce-2012-005

    TRA-967: TIME EXPENDITURE DIFFERENCES AMONG WEEKDAYS, WEEKENDS, AND FRIDAYS FOR RESIDENTS OF MAKKAH, KINGDOM OF SAUDI ARABIA

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    Many researchers have studied the differences in travel behaviours during the weekdays and the weekends for building travel demand in Makkah, Saudi Arabia, any travel demand framework should recognize the differences in residents’ travel behaviour not only between the weekdays and the weekends, but also on Fridays. During the weekends (i.e., Thursday and Friday), most residents spend time with their families and friends on Thursdays, whereas some go to work. On Fridays, there is the Friday prayer, which takes place around noon, and most of the stores are closed until late afternoon. This paper presents modelling of the activity duration for residents of the city of Makkah for weekdays and weekends. The municipality of Makkah collected a full-day travel diary for the residents of Makkah in 2010 for all days of the week. The data were categorized as either weekdays or weekends. Then the multiple discrete continuous extreme value (MDCEV) model was used to estimate the activity duration for 3 separate groups of days (i.e., weekdays, Thursdays, and Fridays), and a fourth model was estimated for all days of the week. This paper will highlight the differences in travel behaviour for the residents of Makkah between the weekdays and the weekends time periods. The outcomes of this paper could be expanded for use in Muslim communities and for all other religions that perform religious rituals during the weekends

    Immobilization of halophilic Aspergillus awamori EM66 exochitinase on grafted k-carrageenan-alginate beads

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    A novel extreme halophilic exochitinase enzyme was produced by honey isolate Aspergillus awamori EM66. The enzyme was immobilized successfully on k-carrageenan-alginate gel carrier (CA) with 93 % immobilization yield. The immobilization process significantly improved the enzyme specific activity 2.6-fold compared to the free form. The significant factors influencing the immobilization process such as enzyme protein concentration and loading time were studied. Distinguishable characteristics of optimum pH and temperature, stability at different temperatures and NaCl tolerance for free and immobilized enzyme were studied. The immobilization process improved optimum temperature from 35 to 45 °C. The immobilized enzyme retained 76.70 % of its activity after 2 h at 75 °C compared to complete loss of activity for the free enzyme. The reusability test proved the durability of the CA gel beads for 28 cycles without losing its activity

    Effect of water softening on the colour intensity of routine haematoxylin and eosin stain

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    ABSTRACT Haematoxylin and eosin (H&E) is the most popular routine stain used in pathology laboratories for highlighting cellular structures. To study the effect of tap water 'softening' (i.e. calcium extraction) on H&E stains, 5 sets of slides from 30 different paraffin-embedded human pathologic tissue blocks were prepared in the same way except for washing with 5 different types of water. Slides washed in untreated tap water showed the best results concerning differentiation and colour intensity, while slides washed with softened or other treated water showed poorer degrees of differentiation and colour intensity. The worst results were obtained from slides washed with water containing sodium bicarbonate. Low calcium and magnesium ions and high sodium ions in soft water adversely affect the results of routine H&E stain

    Enabling interactive safety and performance trade-offs in early airframe systems design

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    Presented is a novel interactive framework for incorporating both safety and performance analyses in early systems architecture design, thus allowing the study of possible trade-offs. Traditionally, a systems architecture is first defined by the architects and then passed to experts, who manually create artefacts such as Fault Tree Analysis (FTA) for safety assessment, or computational workflows, for performance assessment. The downside of this manual approach is that if the architect modifies the systems architecture, most of the process needs to be repeated, which is tedious and time consuming. This limits the exploration of the design space, with the associated risk of missing better architectures. To overcome this limitation, the proposed framework automates parts of the safety and performance analysis in the context of the Requirement, Functional, Logical, and Physical (RFLP) systems engineering paradigm. Safety analysis is carried out by automatic creation of FTA models from the functional and logical flow views. Regarding performance analysis, computational workflows are first automatically created from the logical flow view, and then executed for a set of flight conditions over the range of the mission in order to determine the most demanding condition. Finally, performance characteristics of the subsystems, such as weights, power offtakes, ram drag etc. are evaluated at the most demanding flight condition, which enables the architect to compare architectures at aircraft level. The framework is illustrated with a representative example involving the design of an environmental control system of a civil aircraft, where the safety and performance trade-off is conducted for multiple ECS architectures

    Gajah. Securing the Future for Elephants in India.

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    It is estimated that six in every ten wild Asian elephants live in India. This report by the Ministry of Environment and Forests in India outlines plans to safeguard the species and associated habitats in the face of rapid economic expansion and development pressures

    A study on some biological aspects of longnose trevally (Carangoides chrysophrys) in Hormozgan waters

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    Aspects of the biological features such as age and growth, the reproductive cycle , food and feeding of the Longnose Trevally (Carangoides chrysophrys) were studied from a total 376 specimens collected by use of trawl fishing in Hormuzgan waters between February 2014 and February 2015. The minimum and maximum total length during different months were between 25.5 and 80 cm respectively. Weight-length relationship for Longnose Trevally was W= 0/0064L 2/9004. This fish had an isometric growth. Fishes aged using sections of their otoliths. The equation of growth for Longnose Trevally obtained Lt=85(1-e-0/266(t+1/443)). Total mortality rate for Longnose Trevally was 0.412. LM50 and TM50 for Longnose Trevally was 46 cm, 2 years. Sex ratio(femail : male) for Longnose Trevally was 1/42:1. Maximum absolute and relative fecundity for Longnose Trevally were 479992 and 354 respectively. The highest GSI in April (2.86) and the lowest was in June 2014 (0.43). It has a long spawning season from January to May and spawning peak was observed in May. Longnose Trevally was Relatively low feed (CV= 65.49). Main food for Longnose Trevally were bony fish (Fp= 91.67). Random diet of Longnose Trevally were crustaceans (Fp=4.17) (shrimp, crab and squilla) and mollusks (Fp=4.17) (cutlle fish, Squid), respectively

    Risk analysis of animal–vehicle crashes: a hierarchical Bayesian approach to spatial modelling

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    Driving along any rural road within Western Australia involves some level of uncertainty about encountering an animal whether it is wildlife, farm stock or domestic. This level of uncertainty can vary depending on factors such as the surrounding land use, water source, geometry of the road, speed limits and signage. This paper aims to model the risk of animal–vehicle crashes (AVCs) on a segmented highway. A hierarchical Bayesian model involving multivariate Poisson lognormal regression is used in establishing the relationship between AVCs and the contributing factors. Findings of this study show that farming on both sides of a road, a mixture of farming and forest roadside vegetation and roadside vegetation have significant positive effect on AVCs, while speed limits and horizontal curves indicate a negative effect. AVCs consist of both spatial- and segment-specific contributions, even though the spatial random error does not dominate model variability. Segment 15 is identified as the highest risk segment and its nearby segments also exhibit high risk
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