1,356,628 research outputs found
WiMax technology adoption by SMEs in the city of Jeddah, Saudi Arabia
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This research focuses on developing a framework for Worldwide Interoperability for Microwave Access (WiMax) technology adoption by Small and Medium Enterprises (SMEs) in the Kingdom of Saudi Arabia (KSA). WiMax has emerged as a technology to overcome the limitations of traditional and existing broadband technologies and support a great number of organisations and consumers/citizens in providing a higher speed over substantial distances i.e. in areas that are difficult for wired infrastructure to reach. Despite all the interest in the types of broadband adoption as demonstrated by SMEs in several countries, there seems to be slow progress and lack of information supporting the decision making process for WiMax technology adoption by SMEs specifically in the context of KSA. This may illustrate that SMEs adopt WiMax technology solutions at a slower pace
and make them characterised as laggards in terms of new technologies adoption. This research takes into consideration this literature gap and makes a step forward and investigates on WiMax technology adoption by SMEs in KSA with an organisational cultural view, vendors’ commercialisation strategies
and government policies by analysing the normative literature related to this research. The data collection of this study was carried out in two phases including quantitative and qualitative approaches. The first phase of the research provided results indicated that, the Saudi SMEs who participated in this research are strongly dominated by clan culture and adhocracy culture. These cultures also have a positive impact on the Internet technologies adoption such as WiMax by SMEs. It is found that, the combination of clan and adhocracy cultures in Saudi SMEs is making them more likely to adopt latest Internet technologies. In the second phase, the results showed a wide difference in views among SMEs, WiMax vendors and government agencies involved in WiMax technology diffusion to SMEs in Saudi Arabia. Although WiMax technology started as an innovation that has the potential to be disruptive and could replace the widely diffused fixed wire line Internet connection,
the research findings showed an interesting deviation from this path. In particular, the WiMax technology market analysis in Saudi Arabia highlighted the vendors’ tendency to treat WiMax technology as a sustaining innovation. Research findings also indicated that, the Saudi government provided funds for Information and Communications Technology‘s diffusion in the country.
However, the level of awareness displayed by SMEs is persistently low. Knowledge deployment, mobilisation, innovation directive and subsidy have been emphasised by SMEs as the most important government interventions that might have an impact on WiMax adoption by them. Finally, further
important issues have been uncovered by the research such as taxation, experience exchange, herd culture/bandwagon, consumer right protection and customer service in relation to the adoption of WiMax by SMEs. The perceived future prospect of these additional issues has been considered as an
influence on adoption of WiMax technology by SMEs. The findings of this research can be useful to guide analysts and researchers in determining critical aspects of the complex issues involved in technologies adoption, and lead to suggestions for further valid research
A participatory system dynamics modeling approach to facilitate collaborative flood risk management: A case study in the Bradano River (Italy)
No full textParticipatory methods to support successful policy decisions regarding the complex and dynamic interactions of social, ecological, and physical processes involved in flooding must be simple, easy-to-use, and cost-efficient. Accordingly, a stepwise methodological framework based on causal loop diagrams (CLDs) was developed to address the challenge of context-sensitive initialization of key stakeholders in the collaborative flood risk management process. The methodology consists of five main stages: (i) problem definition, (ii) stakeholder analysis and identification of key groups, (iii) interviews with key stakeholders to construct individual CLDs, (iv) merging of individual CLDs to form a holistic qualitative model representing the entire system, and (v) implementation of an order-oriented reduction process to simplify the final merged CLD, thereby increasing understanding of the most important processes and feedbacks. The proposed approach for flood risk management was tested in a coastal area of southern Italy, a region historically affected by flood events. Given its simplicity, the proposed method was seen as a valuable tool to elicit and map mental models, especially when working with stakeholders who did not have prior modeling experience, i.e., farmers, agricultural companies, tourist complexes, and infrastructure authorities. Indeed, all stakeholders in the current study were able to understand the process and proposed different flood risk management policies, such as land-use changes, management of damage insurance payouts, floodplain activities, and improvement of public awareness. The proposed methodology overcame multiple barriers in initializing stakeholder engagement, including the technical focus of most flood management agencies, the additional cost and time requirements for stakeholder involvement, as well as institutional structures that impede collaborative management. Moreover, the results point to socio-economic aspects of flood risk management that have not been considered in previous modeling studies
Bi-criteria minimization with MWVN–INAM type for motion planning and control of redundant robot manipulators
No full textSUMMARYThis study proposes and investigates a new type of bi-criteria minimization (BCM) for the motion planning and control of redundant robot manipulators to address the discontinuity problem in the infinity-norm acceleration minimization (INAM) scheme and to guarantee the final joint velocity of motion to be approximate to zero. This new type is based on the combination of minimum weighted velocity norm (MWVN) and INAM criteria, and thus is called the MWVN–INAM–BCM scheme. In formulating such a scheme, joint-angle, joint-velocity, and joint-acceleration limits are incorporated. The proposed MWVN–INAM–BCM scheme is reformulated as a quadratic programming problem solved at the joint-acceleration level. Simulation results based on the PUMA560 robot manipulator validate the efficacy and applicability of the proposed MWVN–INAM–BCM scheme in robotic redundancy resolution. In addition, the physical realizability of the proposed scheme is verified in practical application based on a six-link planar robot manipulator.</jats:p
Integrated network application management (INAM)
No full textThis thesis attempts to create a desire for change in DoD's current approach to Network Application Management (NAM). The evolution of NAM into Integrated Network Application Management (INAM) is a crucial component of Network Centric Warfare and achieving Information Superiority and Interoperability. INAM is outlined as three functional requirements, which are Network Awareness, Mission Prioritization linkage to Network Resources, and the Balancing of Service Management. Scenarios play a key role in illustrating the new threats that DoD faces today. These scenarios also identify limitations and challenges to NAM as it exists today. These challenges require significant improvements in flexibility and responsiveness, while providing for wide integration. Trends supporting change are identified in this thesis. Two of the more important trends are the rise of Architectural and Object Oriented Development. Examples such as Training and Testing Enabled Architecture (TENA), Surveillance and Target Acquisition Network (STAN), and Virtual Proving Ground (VPG) are clear examples of these trends. The merging of the Computer Industry's efforts to expand the reach of Operating Systems with the traditional efforts from Network Management is also a trend that is examined. Organizations like Distributed Management Task Force (DMTF) are important to such examinations. Successful change can not be achieved without planning for the transition. This thesis also presents some active transition efforts addressing Network Centric Warfare. TENA, VPG and Naval Postgraduate School's Information Technology Management Master's Program provide three examples of addressing transition in DoD.Approved for public release; distribution is unlimited.Civilian, United States Army Yuma Proving Groundhttp://archive.org/details/integratednetwor10945124
Aspecto alimentario del INAM en Mérida
No full textNDEl estudio determina, por el método de pesada directa de alimentos cocidos, los nutrientes aportados por el Instituto Nacional de Atención al Menor (INAM), a escolares y adolescentes, en cuatro centros ubicados en la ciudad de Mérida. Mediante dos técnicas estadísticas: Análisis Discriminante y Análisis Multivariante de Varianza, se analizan las diferencias que se producen entre los niveles recomendados y los observados en proteínas, grasas, hidratos y kilocalorías. Una variable ficticia, resultado de la combinación de características (sexo, grupo de edad y centro de atención) de los sujetos estudiados, fue necesaria para precisar el origen de las diferencias significativas. Al final, se sugiere adecuar el aporte alimenticio a cada grupo de edad, con el fin de asegurar la ingesta de nutrientes a esos menores recluídos en el INAM
Using FloodRisk GIS freeware for uncertainty analysis of direct economic flood damages in Italy
No full textThe considerable increase in flood damages in Europe in recent decades has shifted attention from flood protection to flood risk management. Assessments of expected damage provide critical information for flood risk management efforts. The evaluation of potential damages under different flood scenarios through quantification of their ability to provide relative short-, medium- and long-term risk reduction, supports decision-makers in discriminating among several alternative mitigation actions. End-users should be aware of, and knowledgeable about, the limitations and uncertainties of such analyses, as well-informed decisions regarding efficient and sustainable flood risk management will become increasingly relevant under future climate and socio-economic changes. In this context, a method was developed to identify and quantify the role of the input parameters in the uncertainty of the potential flood economic damage assessment in urban areas with low sloping/flat terrain and complex topography using a GIS-based, free and open-source software called Floodrisk. Sets of plausible input parameters for the model's two flood loss modelling subroutines (hydraulic modelling and damage estimation) were dynamically combined to quantify the contribution of their inner parameters to the total damage assessment uncertainty. To estimate the contributions of each input to overall model uncertainty, the combination of input parameters that minimized the error in the spatial distribution assessment of the extensive damages affecting (downtown) Albenga (Italy), enumerated after the historical Centa River flood of November 5, 1994, was taken as a reference. In this specific case, a high epistemic uncertainty for the damage estimation module was noted for the specific type and form of the damage functions used. In the absence of region-specific depth-damage functions, the vulnerability curves were adapted from a range of geographic and socio-economic studies. Given the strong dependence of model uncertainty and sensitivity to local characteristics, the epistemic uncertainty associated with the risk estimate was reduced by introducing additional information into the risk analysis. Implementing newly developed site-specific curves and a more detailed classification of the construction typology of the buildings at risk, led to a substantial decrease in modelling uncertainty, along with a decrease in the sensitivity of the flood loss estimation to the uncertainty in the depth-damage function input parameter. These findings indicated the need to produce and openly disseminate data in order to develop micro-scale risk analysis through site-specific vulnerability curves. Moreover, this study highlighted the urgent need for research on the development and implementation of methods and models for the assimilation of uncertainties in decision-making processes
Development and application of a decision support system for optimizing cropping patterns under saline agriculture conditions in Rechna Doab, Pakistan
No full textSecondary salinization processes in arid climates can be managed with effective policy decisions through stakeholder engagement. In developing countries such as Pakistan, effective management solutions also need to consider limited resources such as small land holdings, the poor economic status of farmers, and limited modeling and mathematical skills. This paper is part of a research project conducted to address such challenges via the development of a comprehensive but simple decision support system using a participatory modeling approach. The paper discusses the process of optimizing management on temporal and spatial scales with the consideration of soil salt balance, water availability, and market values of crops. Two major components of the system are: (i) a system dynamics model that describes socio-economic factors such as market values; and ii) a physically based model that simulates the salt balance in the root zone with conjunctive use of canal and tube well irrigation water. The integrated dynamic model was calibrated (R2 = 0.90) and validated (R2 = 0.82) against observed data sets of groundwater depth. Three policy decisions were examined: 1) Base case 2) Bioremediation by growing salt tolerant fodder such as Sudan grass; and 3) Optimum land allocation with different favorable crops (i.e. maximize crop returns while minimizing yield reduction due to salt and water stress). Bioremediation techniques are shown to be helpful in reducing the salt balance of the crop root zone in the long term. Optimizing cropping patterns are found to be effective as a short term solution, but this keeps on increasing the salt balance due to conjunctive water application
Laser welding of polypropylene using two different sources
No full textIn this paper, laser weldability of neutral polypropylene has been investigated using fibre and carbon dioxide lasers. A design of experiment (DoE) was conducted in order to establish the influence of the main working parameters on the welding strength of the two types of laser. The welded samples were characterized by carrying out visual and microscopic inspection for the welding morphology and cross-section, and by distinguishing the tensile strength. The resulting weld quality was investigated by means of optical microscopy at weld cross-sections. The tensile strength of butt-welded materials was measured and compared to that of a corresponding bulk material
Parameter estimation and uncertainty analysis of the Spatial Agro Hydro Salinity Model (SAHYSMOD) in the semi-arid climate of Rechna Doab, Pakistan
No full textManual calibration of distributed models with many unknown parameters can result in problems of equifinality and high uncertainty. In this study, the Generalized Likelihood Uncertainty Estimation (GLUE) technique was used to address these issues through uncertainty and sensitivity analysis of a distributed watershed scale model (SAHYSMOD) for predicting changes in the groundwater levels of the Rechna Doab basin, Pakistan. The study proposes and then describes a stepwise methodology for SAHYSMOD uncertainty analysis that has not been explored in any study before. One thousand input data files created through Monte Carlo simulations were classified as behavior and non-behavior sets using threshold likelihood values. The model was calibrated (1983–1988) and validated (1998–2003) through satisfactory agreement between simulated and observed data. Acceptable values were observed in the statistical performance indices. Approximately 70% of the observed groundwater level values fell within uncertainty bounds. Groundwater pumping (Gw) and hydraulic conductivity (Kaq) were found to be highly sensitive parameters affecting groundwater recharge
- …
