Evaluation of on-demand routing in mobile ad hoc networks and proposal for a secure routing protocol

Secure routing Mobile Ad hoc Networks (MANETs) has emerged as an important MANET research area. Initial work in MANET focused mainly on the problem of providing efficient mechanisms for finding paths in very dynamic networks, without considering the security of the routing process. Because of this, a number of attacks exploit these routing vulnerabilities to manipulate MANETs. In this thesis, we performed an in-depth evaluation and performance analysis of existing MANET Routing protocols, identifying Dynamic Source Routing (DSR) as the most robust (based on throughput, latency and routing overhead) which can be secured with negligible routing efficiency trade-off. We describe security threats, specifically showing their effects on DSR. We proposed a new routing protocol, named Authenticated Source Routing for Ad hoc Networks (ASRAN) which is an out-of-band certification-based, authenticated source routing protocol with modifications to the route acquisition process of DSR to defeat all identified attacks. Simulation studies confirm that ASRAN has a good trade-off balance in reference to the addition of security and routing efficiency

Language thought and literal meaning

PhD ThesisThe notion of literalness in linguistics is based on the following assumptions: Linguistic expressions are vehicle-meaning p airs (since literal meaning has to be the meaning of something). Linguistic expressions have to be cognised a nd used (especially uttered) in order for their meanings to be regarded as literally theirs. "Linguistie, vehicle-meaning relations are fixed and autonomous- - rather than having particular meanings in virtue of being used to express those meanings," linguistie' vehicle-meaning p airs are used to express certain meanings in virtue of having the meanings th at they have. This thesis criticises Chomsky's and Sperber and Wilson's attempts to establish the autonomy of "linguistie'vehicle-meaning pairs. I argue that " Both Chomsky and Sperber and Wilson fail to distinguish "linguistie' semantics from the "real" semantics of what "linguistic" vehicle-meaning pairs are used to express. " They persist in the idea that "linguistic" vehicles are specifically for being uttered (physically instantiated), thus defeating their own purpose of setting the linguistic absolutely apart from what it is used for. " Neither Chomsky's internalist conception of language nor Sperber and Wilson's relevance framework is able to account for the phenomenon of "language misuse", i.e. the use of a "linguistic" vehicle to express the "wrong" meaning. Burton-Roberts' representational conjecture is applied and developed in the presentation of an alternative non/ extra-linguistic account of "literal meaning" and "language use/ misuse". This account has it that neither "linguistic" vehicles nor "linguistic" vehicle-meaning relations are actually linguistic. It avoids the problems attending the notion of linguistic expressions as objects with sortally disjoint and arbitrarily conjoint properties (i.e. physically instantiable "vehicle" and mentally constituted "meaning"), and resolves the unease within Chomsky's Minimalist Program about the inclusion of phonology in I-language. Finally, by way of this resolution, I address some seemingly unrelated issues concerning vehicle-less "meanings" and the relations between l anguage,thought and consciousness

Parity and non-parity determinants of exchange rates in Latin American economies

This paper reports how non-parity fundamental factors together with parity factors are correlated with exchange rate movements. Seven Latin American countries were included in this study using a selection criterion that for a pair of countries to be included, the pair must have more than 50 per cent of trade with the group chosen. The econometric methods applied are appropriate to this topic and include pooled time series regression and seemingly unrelated regression. The findings show that there is support for short and long-run effects on exchange rates from inflation and interest rates. We entered non-parity factors suggested in recent research reports as likely determinants of the exchange rates, and found four non-parity factors that are significantly correlated with exchange rates and these served as control variables in our test model. Our main result shows that both inflation and interest rates are jointly significant factors in most of the tests. The results appear to suggest that exchange rate research should include both non-parity and parity factors. Only then would the parity factor effects be identifiable as relevant to exchange rate formation

Sonocatalytic Degradation of Rhodamine B in Aqueous Solution in the Presence of Tio2 Coated Activated Carbon

AbstractSynthesis of titanium dioxide coated activated carbon (TiO2/AC) has been undertaken using sol-gel method and its application in Rhodamine B (RB) dye removal has been investigated. The synthesized sonocatalyst (TiO2/AC) was characterized by using SEM and FTIR techniques. The effects of the TiO2/AC on the sonocatalytic degradation of RB dye and the operational parameters such as pH, temperature, ultrasonic frequency with the presence/absence of sonocatalyst of the sonocatalytic degradation of RB were concerned in this study. The degradation efficiency of RB in aqueous solution could be achieved 82.21% with the addition of TiO2/AC at the best conditions. The best conditions for sonocatalytic degradation of RB were found to be pH 6, temperature 50°C, ultrasonic frequency of 30kHz with the presence of sonocatalyst for 60minutes

Small-business marketing in Soweto, the importance of the human touch

Small businesses are a crucial element of and a major contributor to the economy and society. They not only provide economic stability for their owners but also meet the needs of society and businesses. Effective marketing communication is needed so that society and business can be informed about the products and services on offer to satisfy their needs. A variety of marketing communication tools can be used by SMMEs to communicate with society and business. This research explores the utilization of these marketing communication tools by SMMEs located in Soweto, Johannesburg. The data were collected by means of a self-administered questionnaire that was circulated and hand-delivered to a sample of SMMEs in Soweto. The findings revealed that SMMEs in Soweto rely more on human interaction, such as word-of-mouth (WOM) and personal selling, to promote their business than on technology-driven tools such as the internet. Keywords: SMMEs, integrated marketing communication, traditional marketing communication, Soweto, promotion. JEL Classification: M3

Financial capability and differences in age and ethnicity

The objective of this study is to disclose the effect of socio-demographic characteristics such as, age and ethnicity which is comprised of Malay, Chinese, Indian and Others on four financial capability domains namely planning ahead, managing money, choosing products and staying informed. A closed ended self-administered questionnaire was disseminated to a total of 2000 respondents among four types of groups which consist of FELDA or rural area residents, private sector employees, government sector employees and youth in institutions of higher learning in Malaysia. Those four groups were selected to cover a wide range of Malaysian population. 500 respondents were involved in this study for each types of groups through purposive sampling technique. Analysis of Variance (ANOVA) and analysis via Statistical Package for Social Science (SPSS) was utilized in this study. The results revealed that age has significant effect on planning ahead, managing money, choosing products and staying informed. Whereas, ethnicities were found to have no effect on financial capability except planning ahead domain. It is suggested that more devotion should be placed on research and professional training in building respondents' financial capability. Furthermore, government and non-government organizations should develop a comprehensive approach to intensify their financial capability and upgrade their standards of living especially of financially vulnerable households

Design of prestressed concrete precast road bridges with hybrid simulated annealing

This paper describes one approach to the analysis and design of prestressed concrete precast road bridges, with double U-shaped cross-section and isostatic spans. The procedure used to solve the combinatorial problem is a variant of simulated annealing with a neighborhood move based on the mutation operator from the genetic algorithms (SAMO). This algorithm is applied to the economic cost of these structures at different stages of manufacturing, transportation and construction. The problem involved 59 discrete design variables for the geometry of the beam and the slab, materials in the two elements, as well as active and passive reinforcement. The parametric study showed a good orrelation for the cost, geometric and reinforcement characteristics with the span length, which can be useful for the day-to-day design of PC precast bridges. A cost sensitivity analysis first indicates that a maximum 20% rise in steel costs leads to an 11.82% increase in the cost, while a 20% rise in concrete costs increases the cost up to 4.20%, namely 2.8 times less. The analysis also indicated that the characteristics of the cost-optimized bridges are somewhat influenced by different economic scenarios for steel and concrete costs. Finally, there is a growth in the volume of concrete when the steel cost rises; surprisingly, the variation in the volume of concrete is almost insensitive to its rising price.This work was supported by the Universitat Politecnica de Valencia (Research Project PAID-06-09) and the Spanish Ministry of Science and Innovation (Research Project BIA2011-23602). The authors are grateful to the anonymous reviewers for their constructive comments and useful suggestions. The authors are also grateful to Dr. Debra Westall for her thorough revision of the manuscript.Martí Albiñana, JV.; González Vidosa, F.; Yepes Piqueras, V.; Alcalá González, J. (2013). Design of prestressed concrete precast road bridges with hybrid simulated annealing. Engineering Structures. 48:342-352. https://doi.org/10.1016/j.engstruct.2012.09.014S3423524

Community-based service use in preschool children with autism spectrum disorder and associations with insurance status

Background: ASD-related services can improve outcomes for children, but less is known about service outside of school settings during preschool age. We aimed to describe amount and category of community-based service use among 3–5-year-old children with ASD and examine differences by health insurance. Methods: We used cross-sectional data on 792 children with ASD diagnoses in the Study to Explore Early Development, a community-based study of neurodevelopment with enrollment between 2012-2016. Mothers reported current child service use and insurance status at study entry. We used log-Poisson and logistic regression to compare service use by insurance group. Results: Nearly 40% of children were not receiving community-based services at study entry. Children with public insurance had fewer total services than children with private or both insurances. After adjustment for sociodemographic confounders, insurance status was not associated with amount of different categories of community-based services. However, children with public insurance alone were least likely to receive community-based behavioral therapy and most likely to receive psychotropic medication compared to other insurances. Conclusion: Many preschool-aged children do not receive community-based services, with receipt of some service types associated with insurance type. Increasing access and availability for evidence-based service, especially for beneficiaries of public insurance, may improve service use and outcomes