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Analysis of Dowlink Macro-Femto Cells Environment Based on Per-Energy CapacityLeón, Jaime 05 1900 (has links)
Placing smaller cells in a heterogeneous cellular network can be beneficial in
terms of energy because better capacities can be obtained for a given energy
constraint. These type of deployments not only highlight the need for appropriate
metrics to evaluate how well energy is being spent, but also raise important issues
that need to be taken into account when analysing the overall use of energy. In this
work, handoff strategies, bandwidth allocation, and path loss models in different
scenarios, illustrate how energy can be consumed in a more efficient way when
cell size is decreased. A handoff strategy based on per-energy capacity is studied
in order to give priority to a more energy efficient handoff option. Energy can
also be spent more adequately if the transmit power is adjusted as a function of
interference. As a result, users can experience higher capacities while spending less
energy, depending whether they handoff or not, increasing the overall performance
of the network in terms of energy efficiency.
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Factors Influencing Program Impact Evaluation in Cooperative ExtensionFlack, Jan Ardis January 2019 (has links)
Impact evaluation (IE) has become a major focus of Extension program evaluation during the past three decades, yet Extension professionals continue to struggle to produce well-documented evidence of program impacts (Lamm, 2011; Workman, 2010).
This research was primarily a quantitative, non-experimental correlational study of factors associated with Extension educators’ IE behaviors and practices in the North Central Region of the Cooperative Extension service. The study employed a comprehensive, systems approach to explore interrelated individual and organizational factors that affect IE in Extension.
A major feature of this research design was the use Structural Equation Modeling (SEM) statistical analysis methodology. The use of SEM to organize and implement this study facilitated simultaneous exploration of many constructs theorized to be involved in IE behaviors in the context of Extension educational program evaluation. Specification of a theoretical, conceptual model to be used to frame the potential relationships among the many constructs and factors was necessary prior to data collection in order to be able to use SEM for data analysis. Data were analyzed using SEM path analysis to determine relationships among the factors.
Significant findings included the identification of the most influential factors on the dependent variable of actual IE behaviors. These were: competency by perceived skill level, behavioral intention, number of roles in IE, education level, and attitude. Factors exhibiting noteworthy influence on factors other than the dependent variable within the model included training, culture, and proportion of teamwork.
Qualitative data themes most frequently mentioned by participants included: the need to know how to measure change; a need for training in general; a need for better planning of programs to achieve impact; conflicting priorities, lack of time and timing/coordination concerns; changing expectations (“moving target”) regarding IE practices and goals; and diverseness in contexts, competencies, and schedules.
Study findings identified a number of influential factors not previously cited in literature, including number of roles in IE; proportion of teamwork employed in IE; a lack of understanding of how to measure change; and issues of diverseness regarding competencies, context (including stakeholder expectations), and scheduling within the Extension organization.
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Capacity of Fading Channels in the Low Power RegimeBenkhelifa, Fatma 01 1900 (has links)
The low power regime has attracted various researchers in the information theory and
communication communities to understand the performance limits of wireless systems. Indeed,
the energy consumption is becoming one of the major limiting factors in wireless
systems. As such, energy-efficient wireless systems are of major importance to the next
generation wireless systems designers. The capacity is a metric that measures the performance
limit of a wireless system. The study of the ergodic capacity of some fading channels
in the low power regime is the main subject of this thesis. In our study, we consider that the
receiver has always a full knowledge of the channel state information. However, we assume
that the transmitter has possibly imperfect knowledge of the channel state information, i.e.
he knows either perfectly the channel or only an estimated version of the channel. Both
radio frequency and free space optical communication channel models are considered.
The main contribution of this work is the explicit characterization of how the capacity
scales as function of the signal-to-noise ratio in the low power regime. This allows
us to characterize the gain due to the perfect knowledge compared to no knowledge of
the channel state information at the transmitter. In particular, we show that the gain increases
logarithmically for radio frequency communication. However, the gain increases
as log2(Pavg) or log4(Pavg) for free-space optical communication, where Pavg is the average
power constraint imposed to the input. Furthermore, we characterize the capacity of cascaded fading channels and we applied the result to Rayleigh-product fading channel and
to a free-space optical link over gamma-gamma atmospheric turbulence in the presence of
pointing errors. Finally, we study the capacity of Nakagami-m fading channel under quality
of service constraints, namely the effective capacity. We have shown that the effective
capacity converges to Shannon capacity in the very low power regime.
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The source of life: activity, capacity, and biology in Aristotle's account of soulJulian, Brian 18 November 2015 (has links)
Aristotle discusses the nature of soul in De Anima, defining it as the "form of a natural body having life potentially" or "first actuality of a natural, instrumental body." I argue that these definitions characterize soul as the capacity for the activity of life. In chapter one I examine key terminology from Aristotle’s account of soul: the terms used to discuss soul, life, and the vital functions. In particular, the soul and life terminology must be kept separate, as must the terms referring to vital capacities and those referring to vital activities. In chapter two I use these terminological distinctions to trace Aristotle’s arguments for his definition of soul, contending that they begin by positing life as the vital activities and soul as the cause of life. From that beginning, Aristotle twice argues for a definition of soul, in De Anima 2.1 and 2.2. In the transition between the two arguments Aristotle says that the first is sketched in outline and that a proper definition shows the cause. While this is usually taken to mean that Aristotle prefers the second definition, I argue that the definitions reached are the same. In chapter three I argue that Aristotle’s definitions of soul state that it is the capacity for life. He defines it as a first actuality, and upon examination this phrase means that it is a capacity. He also defines it as a form and calls form an actuality, but I explain that due to the relativity of actuality and potentiality, it is permissible to view form as a capacity as well. In chapter four I reconcile the general account of soul as a capacity with Aristotle’s discussions of a particular kind of soul, examining what he says in De Anima and his biological works about the most fundamental kind—the nutritive. Aristotle locates nutritive soul in the heart and says that it is responsible for the size of an organism, but this fits with nutritive soul also being the capacity of an organism to nourish itself. I also discuss why Aristotle says the body is the instrument of soul.
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Vegetation and flora of the Kosi Bay Coastal Forest Reserve in Maputaland, northern KwaZulu-Natal, South AfricaLubbe, Richard Andrew January 1996 (has links)
The vegetation of the Kosi Bay Coastal Forest Reserve was classified by means of Braun-Blanquet and TWINSPAN procedures. Twelve major plant communities were identified,
occurring along a gradient from the inland fresh water habitats, to the beach with influences
from strong winds and salt spray. Some of these communities were further divided into plant
communities and sub-communities giving a total of 27 plant communities and three sub-communities.
A vegetation map was compiled for the study area using Geographical
Information System procedures. Veld condition was good and the grazing capacity high
ranging between 2.9 and 5.6 ha/LSU (cattle). A checklist of 1 164 vascular plant species
collected in the study area was compiled. The distribution of 71 plant species endemic to the Maputaland Centre of Endemism was related to plant communities. The coastal grassland
communities were prioritized for conservation, as a large number of Maputaland Centre
endemics are restricted to these communities. / Dissertation (MSc)--University of Pretoria, 1996. / Plant Science / MSc / Unrestricted
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The role of school governing bodies in Rural Section 21 schools in Sisonke DistrictDuma, Bongumusa Edmund January 2018 (has links)
A thesis submitted to the Faculty of Education in fulfillment of the requirements for the Degree of Master Of Education in the Department of Comparative and Science Education at the University of Zululand, 2018 / In the Manual: Guidelines for capacity building of school governing body members, South Africa (2015:12), “research indicates that most of the newly elected SGB members do not have the necessary capabilities to govern schools at the required level”. This view is corroborated by Pamillis (2005:23)’s assertion that “a common obstacle to democratic functioning of schools governing bodies in South Africa is the lack of capacity among many SGB members who may have not only insufficient knowledge of the legal requirements and rights of SGBs, but also lack the necessary education and skills to manage the school’s finances and business dealings and over above these deficiencies the SGB members may lack adequate support systems from the educational bureaucracy. Arguably, it is in light of these possible deficiencies that the South African Schools Act requires provincial departments of education to provide capacity-building programmes for governing bodies. Thus, as a consequence of this lack of the requisite capabilities, “experiences with decentralisation in education are somewhat mixed and often disappointing” (Azfar et al., 2001:8). This prevailing situation in respect of the lack of requisite governance skills is accounted for by the fact that “in South Africa a form of decentralisation has evolved that is strong in terms of devolution, but weak in terms of managing the disparate and often discriminatory proclivities and tendencies within local sites” (Azfar et al., 2001:8). What transpires from this is that “decentralisation South Africas not necessarily promote allocative efficiency […]” (Azfar et al., 2001:8). Thus, Azfar et al., (2001:8) view in this regard is that “whether decentralisation in fact improves or harms public sector performance appears to depend on formal institutional arrangements, as well as their interaction with social practices which influence the implementation of decentralised governance.” It is against this backdrop, therefore, that van Wyk (2007:137) argues that “in ceding power to the local site, the model in use in South Africa has failed to take account of diversity at the local level.” It is worth noting though that despite the failure cited by van Wyk, decentralisation as a pragmatic governance strategy is not dismissed willy-nilly. This view is corroborated by van Wyk’s (2007:137) argument that “the shift to decentralised school governance and management requires SGB members to develop a wide range of skills and capacity to deal with the complex issues and tasks they are expected to fulfil”. Thus, as a response to this predicament, “teachers often mentioned the necessity of providing appropriate training for school governors, particularly the parent representatives” (Van Wyk, 2007:137). Arguably, “skills deficit among SGB members weaken the effective functioning of SGBs (Van Wyk, 2007:135). The situation under discussion is exacerbated by and large by the fact that “there is a lack of accountability and possible participation problems in the relationship between schools and their governing bodies” (Transparency, 31). In the context of this study it is noted that “although the South African schools Act envisioned a system where schools would be community owned and controlled […]”, it is regrettable that “communities still perceive schools as belonging to government and teachers” (Transparency,31). Thus, in light of the numerous challenges cited above as being contributory factors on the seeming ineffectiveness of decentralisation in the education sector, this study sought to establish how best decentralised governance in schools could be harnessed notwithstanding its attendant constraining factors.
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Investigating Freeway Speed-Flow Relationships for Traffic Assignment ApplicationsSaberi Kalaee, Meead 01 January 2010 (has links)
Developments in high resolution traffic sensors over the past decades are providing a wealth of empirical speed-flow data. Travel demand models use speed-flow relationships to assign traffic flows to network links. However, speed-flow relationships have not been revalidated against new detailed traffic sensor data. Therefore, it is necessary to revisit speed-flow relationships based on actual measured conditions on network links rather than assuming constant speed-flow relationships over entire highway network systems. Speed-flow relationships have been particularly difficult to calibrate and estimate when traffic volumes approach capacity, i.e. when the v/c ratio approaches one. This thesis empirically evaluates the speed-flow relationships for v/c < 1 using field data. For congested conditions (v/c > 1) a theoretical approach is taken. A new methodology to determine the distribution of the activation of bottlenecks, bottleneck duration, and bottleneck deactivation is proposed. This thesis is a new contribution to understand the stochastic nature of freeway capacity as well as bottleneck duration, activation, and deactivation. Unlike previous research efforts, this thesis studies speed-flow relationships at the lane level and later presents a method to estimate speed-flow relationships at the link level.
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Optimal Signaling Strategies and Fundamental Limits of Next-Generation Energy-Efficient Wireless NetworksRanjbar, Mohammad 29 August 2019 (has links)
No description available.
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Climate related hazards and changes in adaptive capacityWedholm, Johanna January 2021 (has links)
This thesis aims to explore whether and how the frequency and severity of climate-related hazards are associated with changes in adaptive capacity. Despite increased hazard frequency and severity in the world, it is still contested whether hazard frequency and severity are associated with changes in adaptive capacity, often referred to as the preconditions necessary to enable adaptation. The ‘disaster-reform’ position holds that increased frequency and severity can create critical junctures providing legitimacy for governmental action and windows of opportunity for change in adaptive capacity. The ‘conservative’ position holds that exposure to frequent and severe climate-related hazards tends to be overwhelming and create a policy environment where change is unlikely. It further argues that exposure can hinder change in adaptive capacity due to the complexity in maintaining public support long enough for substantial changes in adaptive capacity since initial improvements can be perceived as successes. The method of choice to explore the association is linear regression analysis on the correlation between the frequency and severity of climate-related hazards measured in the International Disasters Database 2008-2016 and changes in adaptive measured in the World Risk Index for 180 countries in 2011-2019. This study shows that climate-related hazard frequency and severity are generally unassociated with adaptive capacity change in line with the ‘conservative’ position. Despite the lack of a global correlation, some countries deviate from the pattern by having significant improvements in adaptive capacity after exposure to frequent and severe climate-related hazards, thus confirming the ‘disaster-reform’ position. In addition to supporting the ‘conservative’ position, these results highlight the potential for future studies on the causal mechanisms behind the countries deviating from the overall pattern.
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Fyzická aktivita při léčbě kardiorespiračních poruch u dětí s dětskou mozkovou obrnou / Physical activity in the treatment of cardiorespiratory disorders for children with cerebral palsyMheni, Syrine January 2021 (has links)
Children with cerebral palsy have lesser cardiorespiratory endurance (or aerobic capacity) and less physical activity than children who are developing normally. Cardiorespiratory problems are linked to a higher risk of noncommunicable diseases and premature aging. The goal of this research is to discover aspects that can be added in physiotherapy practice to ensure a long-term improvement in aerobic capacity in children with cerebral palsy while engaging in physical activity. Also investigated is the effect of aerobic capacity on functional abilities. A systematic review of the literature was undertaken utilizing the PubMed, Cochrane Library, ScienceDirect, and PEDro databases. The child's cardiorespiratory fitness appears to improve when they engage in high- intensity, goal-directed physical activity. The child's adherence appears to be aided by a motivating intervention and the removal of environmental barriers to the activity's practice. This allows for a long-term increase in aerobic capacity. It was impossible to draw a direct link between this improvement and functional capacity. Few studies have incorporated cerebral palsy and low global motor skills in recent years. Despite the importance of the findings, their heterogeneity prevents generalizable suggestions for all children with cerebral...
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