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Water Availability Is A Principal Driver Of Large-Scale Land Cover Spatial Heterogeneity In Sub-Saharan Savannahs
No full textContext
The heterogeneous mosaic nature of African savannah vegetation is a key aspect of its ecology. This study evaluates mosaic distributions and characteristics across sub-Saharan Africa, investigating the environmental drivers of mosaic formation.
Objectives
This study was designed to determine: (1) on a continental scale, how frequent are mosaics in savannahs? and (2) what are the key environmental drivers in the formation of mosaics?
Methods
Landsat ETM+ satellite imagery was used to generate land-cover maps for 39 sample areas across sub-Saharan Africa. The spatial complexity of land-cover mosaics at 4628 savannah sub-sites was quantified, and modelled using random forests to identify the relative importance of environmental variables driving mosaic presence.
Results
Only six sub-sites constituted a single land-cover class, illustrating that mosaic habitats are abundant at the scale analysed (19.6 km2), although mosaic characteristics varied considerably. Results indicate precipitation is most important in influencing mosaic complexity, followed by evapotranspiration, temperature, lithology and distance to rivers. Fire and ecosystem engineer presence are of lesser importance at this study scale.
Conclusions
Mosaics are ubiquitous in the African savannahs studied, their presence influenced by multiple environmental drivers, with water being key. The lower importance of fire and large mammal disturbance is likely resulting from these highly individualistic site-based process varying between sites, resulting in no single, coherent, across-Africa disturbance signal, and/or lack of detail in available data at this scale. Therefore, large-scale determinants of savannah mosaics appear climate-driven. Under future global warming scenarios, African savannahs are likely to become more homogenous
Unifying Prolepsis And Cross-Clausal Cliticization In Lubukusu
No full textThis paper examines proleptic constructions in Lubukusu (Bantu, Western Kenya). I find that Lubukusu has two distinct strategies for prolepsis: one where the extra matrix nominal is base-generated high, and one where the nominal moves from the embedded clause to the matrix position. The latter is subject to island effects, whereas the former is not. I propose an analysis for these two kinds of prolepsis based on these facts, dependant on the particularities of what nominals can be licensed in what syntactic positions in Lubukusu, and explore the cross-linguistic implications of this analysis
Rentolog 5 Phase Inductor Motor Analysis
No full textThe working of 5 phase inductor is design to work in the same principle. Similar to the working of three phase induction motor, five phase induction motor works on the application of Faraday's law and Lorentz force on conductor. When five phase ac supply is given to the stator winding which are spatially and time displaced by displaced by 72°the rotating magnetic field is produce which rotates at synchronous speed. When short circuited rotor (squirrel cage) is placed in rotating magnetic field an EMF is induced in the rotor conductor due to electromagnetic induction. Due to this EMF, current starts flowing in the rotor conductor and sets up its own magnetic field. Due to interaction of these two magnetic fields, a torque is produced and conductor tends to move. A hole cut at the center of the drive shaft inside the rotor. An insulator is installed in the hole to act as a regulator, to control excess magnetic field. The component of the system is coated with oil film plate to reduce over heating (the idea was gotten from umbrella usage)
A Basic Introduction To The Design Features Of A Modern Operating Theatres And Working Principles In Khartoum - Sudan
No full textDesigning of an operation suite complex is a major exercise and is mainly intended to benefit the patient. The need for safety, convenience and economy will guide the planning of a modern operation theatre complex, whatever the size, number or the specialty. Guidelines based on current and widely accepted recommendations as also ones for possible expansion of the operation theatre complex are dealt with in this article
Overt Subjects And Agreement In Zulu Infinitives
Get PDFThis paper explores a surprising interaction of agreement and concord inside infinitive clauses in Zulu. In Zulu, as in many Bantu languages, infinitive verbs are marked with noun class 15/17 morphology. Internal arguments of infinitives are typically unmarked, while the external argument must receive so-called associative morphology and must precede internal arguments. I argue that the external argument in these constructions is realized in Spec,vP, a finding that has a number of consequences for our understanding of clause structure and agreement in Zulu and related languages
Reconstructable Main Clause Functions Of Proto-Bantu Applicative * -Ɪd
Get PDFThis chapter presents evidence in favour of reconstructing at least three mainclause-level functions of the Proto-Bantu (PB) applicative *-ɪd: (i) the introduction of a semantic role which cannot be expressed otherwise with an underived verb root; (ii) the focalisation of a constituent with a Location related semantic role (most commonly General Location of the event); and (iii) the addition of aspectual and semantic nuances of completeness, iterativity or thoroughness to the meaning of the verb root. With respect to the syntactic function in (i) evidence is provided in favour of the hypothesis that PB *-ɪd introduced a Spatial/Goal or Location argument and that this function later extended to Human Goals and Beneficiaries. Finally, the chapter establishes possible diachronic relations among the three reconstructed functions of *-ɪd
NEETE - Next Evolution Enhanced Text Editor, A Visual Text Editor
No full textComputer programming is currently an exercise lled with di culties in communication and understanding of the material. Most typical programming tools create little to no opportunity to communicate design and intentions to software practitioners who may encounter other people's creations. My view is that the lack of a clear and visible structure in complex systems exacerbates the problem. I am of the belief that pictures and diagrams present an attractive option for improving communication. Therefore, a means of creating diagrammatic views of computer programs is presented in the form of Next Evolution Enhanced Text Editor (NEETE). NEETE allows the creation of a higher level diagrammatic representation of the textual code, thus enabling the manipulation and exploration of the design in a multidimensional and hierarchical plan
Analysis of Dividend Policy and Stock Return in Nairobi Securities Exchange, Kenya
No full textGlobal Securities Exchange witnessed slow performance between 2009 and 2018. Foreign direct investment declined in developed countries and also in Africa. In Kenya, Nairobi Securities Exchange Witnessed Volatile performance during the study period with 2011 and 2015 revealing bear run. During the period of volatility, making investment decisions by investors may have been challenging. Performance indicators such as NSE 20 Share Index, market capitalization, equity turn over, liquidity of stocks all were not stable and witnessed downward trend within the study period. The study sought to analyze the relationship between dividend policy and stock return in Nairobi Securities Exchange. The study is anchored on stock return theories and dividend policy theories .Reviewed literature revealed varied results. Studies reviewed used different methodology and variables arriving at conflicting results. Limited studies reviewed conform to the present study. The study adopted longitudinal research design; the target population was Nairobi Securities Exchange. Secondary data was drawn from Nairobi Securities Exchange. Results revealed that dividend policy significantly influence stock return (R2=0.1882, p=0.024<0.05), consequently, dividend yield has an inverse significant relationship on stock return in Nairobi Securities Exchange, (p=0.007<0.05). Result of this study is useful to policy makers, investors, regulators and finance analyst
Are Mathematical Relationships Represented by Geometries in Some Functional State Space?
No full textHuman-Centric Functional Modeling is considered in this paper to be a branch of network theory which hypothesizes that all systems can be represented as having a set of functions through which the system might transition from one functional state to another. These states are referred to as “functional states” because they are described solely in terms of the functions available to transition to adjacent states, rather than being described in terms of any entities that might implement those functions. All possible behaviors of the system are then hypothesized to be described by a graph containing a network of nodes representing such functional states, where those nodes are connected by edges representing the processes through which those functional states might transition between each other. Modeling human cognition as moving through a “space of concepts” or “conceptual space” that forms the functional state space of the cognitive system and that has the capacity to represent all possible concepts and reasoning, it has been hypothesized that all information and therefore all mathematical proofs and other logic can be represented in this space. Modeling human conscious self-awareness as moving through an “awareness space” or “space of awareness's” that represents the functional state space of the consciousness, it has been hypothesized that awareness of any mathematical or other truth, whether or not yet identified or proven, can be represented as a potential awareness in that space. This paper outlines the hypotheses that in the limit of infinite ability to navigate logic through understanding or reasoning processes (infinite intelligence) mathematical logic is represented by a geometry in conceptual space, and that in the limit of infinite ability to be aware of truth (infinite awareness), mathematical truth is represented as a geometry in awareness space. This paper also outlines some of the questions that must be answered in order to validate these hypotheses
The Potential For Scaling Up Container-Based Sanitation In Informal Settlements In Kenya
No full textKenya has enshrined the right to sanitation in the 2010 constitution. Achieving this requires scaling up infrastructure and models of delivery beyond sewer networks that have previously been the focus. In Kenya, two enterprises, Sanergy and Sanivation, have been providing new forms of off-grid services with container-based sanitation (CBS). This paper uses a political economy analysis to understand the incentives, institutions and power dynamics that are enabling or constraining the potential for such off-grid sanitation models. The paper outlines six core problems to be addressed in the pursuit of scaling up: fragmented governance; sustainability of CBS enterprise models; service delivery planning in informal settlements; personal power rather than institutions in decision-making; vested local interests; and land tenure and political connection. It discusses how stakeholders might work collaboratively to progressively address or recognise these issues