3,338 research outputs found
Thermal and solutal stratification on MHD nanofluid flow over a porous vertical plate
Nanoparticles have the highest credibility to develop the thermal properties compared to conventional particle fluid suspension. Thermal and solutal stratification on heat and mass transfer induced due to a nanofluid over a porous vertical plate is analyzed. The transport equations engaged in the study include the effect of Brownian motion and thermophoresis particle deposition. The nonlinear governing equations and their related boundary conditions are initially looked into dimensionless forms by similarity variables. The resulting equations are solved numerically utilizing the fourth-fifth order Runge–Kutta–Fehlberg method with shooting technique (MAPLE 18). It is investigated that the temperature of the nanofluid and the concentration fraction decelerate with increase in thermal and solutal stratificatio
Identification of Continuing Professional Development Needs of Primary School English Teachers of Kuala Terenganu District
The study was carried out mainly to identify the perceived needs
for continuing professional development of primary school English
teachers of Kuala Terengganu District. It also sought to find out the
relationship between selected variables and the perceived needs for
continuing professional development.
The data was collected using a questionnaire from 82 primary
school English teachers of Kuala Terengganu district. The findings of
the study indicated that majority of the respondents have high
perceived needs for continuing professional development. The study
also revealed that the respondents have perceived needs in all the six categories identified in the questionnaire which were (A) Knowledge, (B)
Teaching Strategies, (C) Classroom-Based Skills, (D) Pastoral Care, (E)
Student Management Skills and (F) Personal Development. It was found
that there was a significant correlation between age and perceived
needs for continuing professional development but it was low in
nature.
The study recommended that provision of professional
development activities for primary school English teachers of Kuala
Terengganu District should be based on a needs assessment and
teachers should be allowed to choose in-service courses based on their
own needs.
The study has also suggested that further research should be
conducted to obtain a more in-depth view of the perception of
professional needs of English teachers through other research designs
Some characteristics of the larval breeding sites of Anopheles culicifacies species B and E in Sri Lanka
Background & objectives : Anopheles culicifacies Giles, the major malaria vector in Sri Lanka, existsas a species complex comprising two sympatric sibling species— species B and E. Species E is reportedto be the major vector of Plasmodium vivax and P. falciparum parasites in Sri Lanka, whilst speciesB is a poor or nonvector as in India. Knowledge of the breeding habits of the two sibling species canhelp in designing optimal vector control strategies. Hence, a survey was conducted in Sri Lanka tostudy the preferential breeding habitats of An. culicifacies species B and E.Methods: Immature forms of An. culicifacies were collected from identified breeding sites in malariousdistricts. Collected larvae were typed for their sibling species status based on mitotic Y-chromosomestructure. Data was analysed using Statistical Package for Social Science version 10.0.Results: An. culicifacies immature forms were found in 23 collection sites. Among these samples19 were found to have species E and four to have species B. All species B larvae were collected fromTonigala village in the Puttalam district. None of the 23 sites was found to have both species B and E.Species E, the major vector of malaria, appears to breed in variety of breeding sites which can be of anindication of its adaptive variation to exploit breeding sites with varying limnological characteristics.Interpretation & conclusion: The present findings have to be taken into account when formulatingmore effective larval control measures. They also show the need for a detailed study of possibledifferent preferences for larval breeding sites between species B and E
A unified approach to cooperative and non-cooperative sense-and-avoid
Cooperative and non-cooperative Sense-and-Avoid (SAA) capabilities are key enablers for Unmanned Aircraft Vehicle (UAV) to safely and routinely access all classes of airspace. In this paper state-of-the-art cooperative and non-cooperative SAA sensor/system technologies for small-to-medium size UAV are identified and the associated multi-sensor data fusion techniques are introduced. A reference SAA system architecture is presented based on Boolean Decision Logics (BDL) for selecting and sorting non-cooperative and cooperative sensors/systems including both passive and active Forward Looking Sensors (FLS), Traffic Collision Avoidance System (TCAS) and Automatic Dependent Surveillance - Broadcast (ADS-B). After elaborating the SAA system processes, the key mathematical models associated with both non-cooperative and cooperative SAA functions are presented. The analytical models adopted to compute the overall uncertainty volume in the airspace surrounding an intruder are described. Based on these mathematical models, the SAA Unified Method (SUM) for cooperative and non-cooperative SAA is presented. In this unified approach, navigation and tracking errors affecting the measurements are considered and translated to unified range and bearing uncertainty descriptors, which apply both to cooperative and non-cooperative scenarios. Simulation case studies are carried out to evaluate the performance of the proposed SAA approach on a representative host platform (AEROSONDE UAV) and various intruder platforms. Results corroborate the validity of the proposed approach and demonstrate the impact of SUM towards providing a cohesive logical framework for the development of an airworthy SAA capability, which provides a pathway for manned/unmanned aircraft coexistence in all classes of airspace
Model multiple antigenic and homopolymeric peptides from non-repetitive sequences of malaria merozoite proteins elicit biologically irrelevant antibodies
AbstractThree model peptides containing B-epitopes from conserved, non-repetitive regions of the merozoite surface antigens, MSA2 and MSA1, and the erythrocyte binding protein EBP of Plasmodium falciparum were synthesised. The peptides incorporated GPG spacers and C residues at the N and C termini, and were polymerised by oxidation to form cystine bridges. Multiple copies of essentially the same peptide sequences were also synthesised on a branching lysyl matrix to form a tetrameric multiple antigen peptide. Rabbits were immunised with the polymerised and multiple antigen peptides, in alum followed by Freund’s adjuvant, and the antibody responses examined by IFA and ELISA. Reproducible antibody responses were obtained against the MSA1 and EBP but not MSA2 peptides. IgG antibody levels detected by ELISA after three injections of antigen in alum, increased significantly after further immunisation in Freund’s adjuvant. IgG levels were largely maintained for at least 23 weeks after the final immunisation. IgM antibodies, generally detectable only after immunisation in Freund’s adjuvant, were absent 23 weeks later. Antibody titres against the native protein on fixed parasites, assayed by IFA, were three to five orders of magnitude lower than the corresponding ELISA titres against the peptides. Antibody-dependent inhibition of P. falciparum growth in vitro could not be demonstrated with the immune rabbit sera. The MSA1 and EBP peptides elicited cross-reactive antibodies. The results suggest that the selected non-repetitive sequences are conformationally constrained in the native proteins and only a small proportion of the anti-peptide antibodies bind to the native proteins. The significance of the findings for the development of peptide vaccines and the use of peptides in immunoassays is discussed
Bond refunding in postbellum New Orleans: The premium bond plan
The plan put forth by the City\u27s Administrator of Finance, Mr. D.H. Adler, was known as the Premium Bond Plan and was designed to liquidate the City\u27s bonded indebtedness over a 50-year period. Under this plan, which was adopted by the City Council on May 25, 1875 (New Orleans City Ordinance 3130) and ratified by the Louisiana Legislature on March 6, 1876 (La. Laws 1876, Act 31), existing bonds, whose coupon rates averaged 7.5% (Phillips, p. 5), would be converted into 5% Premium Bonds : redeemable from one to fifty years in the future. One million bonds, of $20 denomination, would be issued in 10,000 series of 1.00 bonds each
PREDICTIVE TIME MODEL OF AN ANGLIA AUTOFLOW MECHANICAL CHICKEN CATCHING SYSTEM
In this project, a predictive time model was developed for an Anglia Autoflow mechanical chicken catching system. At the completion of poultry growout, hand labor is currently used to collect the birds from the house, although some integrators are beginning to incorporate mechanical catching equipment. Several regression models were investigated with the objective of predicting the time taken to catch the chicken. A regression model relating distance to total time (sum of packing time, catching time, movement to catching and movement to packing) provided the best performance. The model was based on data collected from poultry farms on the Delmarva Peninsula during a six-month period. Statistical Analysis System (SAS) and NeuroShell Easy Predictor were used to build the regression and neural network models respectively. Model adequacy was established by both visual inspection and statistical techniques. The models were validated with experimental results not incorporated into the initial model.Livestock Production/Industries,
Communication, navigation and surveillance performance criteria for safety-critical avionics and ATM systems
The demand for improved safety, integrity and efficiency due to the rapid growth of aviation sector and the growing concern for environmental sustainability issues poses significant challenges on the development of future Communication, Navigation and Surveillance/Air Traffic Management (CNS/ATM) and Avionics (CNS+A) systems. High-integrity, high-reliability and all-weather services are required in the context of four dimensional Trajectory Based Operations / Intent Based Operations (TBO/IBO). The Next Generation Flight Management Systems (NG-FMS) and the Next Generation Air Traffic Management (NG-ATM) systems are developed allowing automated negotiation and validation of the aircraft intents provided by the NG-FMS. After describing the key system architectures, the mathematical models for trajectory generation and CNS performance criteria evaluation are presented. In this paper, the method for evaluating navigation performance is presented, including a detailed Monte Carlo simulation case study. The proposed approach will form a basis for evaluating communication and surveillance performances as well in future research. The Monte Carlo simulation results demonstrate the capability of the proposed CNS+A system architectures to comply with the required navigation performance criteria in the generation of optimized aircraft trajectory profiles
- …