140,495 research outputs found
Comparacion entre las distribuciones Lognormal y Chaudhry – Ahmad en hibridos del género Populus
No full text35 p.Uno de los géneros forestales con más oportunidades económicas y de desarrollo dentro del sector forestal chileno es el género Populus, históricamente se han introducido una baja cantidad de híbridos comerciales, entre los que se destacan los Populus x euroamericana cv I – 488 e I -63/51. Para poder modelar la distribución de los diámetros, se utilizaron las funciones de densidad de probabilidad (f.d.p), siendo las más conocidas la distribución Normal, Weibull, Lognormal, entre otras. En esta memoria se comparó la distribución Lognormal y la de Chaudhry – Ahmad en la modelación de la estructura horizontal de híbridos del género Populus. Las funciones se ajustaron a los datos, obteniendo el estadístico dn, el que se usó para realizar el análisis de varianza utilizando la transformación (1/(dn)) para cumplir con los supuestos de normalidad y homocedasticidad. Las variables estudiadas fueron edad, distribución e híbrido, presentando diferencias significativas solamente la variable distribución, mostrando evidencia estadísticamente significativa entre ambas distribuciones, siendo la distribución Lognormal la que modela de mejor manera los híbridos I – 488 e I – 63/51 ya que posee un promedio para el estadístico (1/(dn)) menor que la distribución Chaudhry – Ahmad. El mayor aporte que presenta esta memoria es el descubrimiento de un error en la publicación original de la distribución Chaudhry – Ahmad, lo que permitirá su correcta divulgación
REITs and Idiosyncratic Risk
No full textThis study examines various determinants of idiosyncratic risk from the perspective of un-diversified REIT investors, managers holding options, other option holders, and arbitrageurs. Since real estate investment trusts (REITs) enjoy a unique organizational structure and tax status, the relevant determinants derived from the two-stage regression model are different from other industrial firms. Results suggest that efficiency, liquidity and earnings variability are the important determinants of idiosyncratic risk, whereas size and capital do not
The relationship of childhood bullying and paranoid thinking in a clinical population: the role of mediators
No full textA wealth of research evidence has been accumulating over the last two decades, highlighting the association of childhood trauma and psychosis. However, research has focused more on investigating the prevalence of childhood trauma in individuals with psychosis and not much consideration has been given to the role of underlying processes which may mediate this association.Following a comprehensive literature review search, 32 studies were identified which fulfilled the search criteria and investigated the association between childhood trauma and psychosis in adulthood. This narrative literature review evaluates empirical evidence generated over the last two decades and builds upon the previous literature reviews in this area. In addition to the discussion of the prevalence of childhood trauma in psychosis, theoretical bases, causality, mediation, consideration has been given to the controversial and debatable issue of asking about childhood trauma from clients with psychosis.The methodological limitations of the literature reviewed, as well as directions for future research have been offered. As the association of childhood trauma and psychosis can have far reaching implications, both in terms of assessment and intervention, these have been discussed in the final part of this review
People and protected areas: some issues from India Maan, S. J. Chaudhry, P.
No full textIndia is one of the 17 mega biodiverse countries, occupying only 2.5 % of the world’s geographical area and 1.8 % of the its forest area but supporting 16 % of the world’s human population and 17 % of its livestock population. Biotic pressure on the country’s protected areas is tremendous and managers of these areas face an uphill task in balancing divergent needs of different stakeholders of national parks and wildlife sanctuaries. The job of managing such areas is highly challenging because of the many difficult issues such as human–wildlife conflicts, encroachments, overgrazing, tourists’ pressure (including pilgrimages into the forests), poaching, and an ever–increasing demand for diversion of protected areasfor development purposes. In the present article we discuss some of these issues with reference to India and emphasise the danger of losing ecosystem services (mostly of an intangible or regulating kind of nature) emanating out of these protected areas.La población y las zonas protegidas: algunos problemas en la India La India es uno de los 17 países con más biodiversidad, ocupa solo el 2,5 % de la superficie del mundo y el 1,8 % de la superficie forestal mundial, y alberga el 16 % de la población humana y el 17 % del número de cabezas de ganado del mundo. La presión biótica en las zonas protegidas del país es tremenda y los gestores de estas zonas se enfrentan a la tarea cada vez más ardua de encontrar un equilibrio entre las necesidades divergentes de las diferentes partes interesadas de los parques nacionales y las reservas naturales. Existen numerosos problemas, como los conflictos entre humanos y la fauna silvestre, las invasiones, el pastoreo excesivo, la presión turística (con inclusión de los peregrinajes a los bosques), el furtivismo o la creciente demanda de zonas protegidas con fines de desarrollo, que dificultan la labor de gestión de estas zonas. En el presente artículo, hemos analizado algunas de estas cuestiones con referencia a la India, a la vez que se hace más hincapié en el peligro que supone perder los servicios ecosistémicos (en su mayoría, de carácter intangible o regulador) que se derivan de estas zonas protegidas.La población y las zonas protegidas: algunos problemas en la India La India es uno de los 17 países con más biodiversidad, ocupa solo el 2,5 % de la superficie del mundo y el 1,8 % de la superficie forestal mundial, y alberga el 16 % de la población humana y el 17 % del número de cabezas de ganado del mundo. La presión biótica en las zonas protegidas del país es tremenda y los gestores de estas zonas se enfrentan a la tarea cada vez más ardua de encontrar un equilibrio entre las necesidades divergentes de las diferentes partes interesadas de los parques nacionales y las reservas naturales. Existen numerosos problemas, como los conflictos entre humanos y la fauna silvestre, las invasiones, el pastoreo excesivo, la presión turística (con inclusión de los peregrinajes a los bosques), el furtivismo o la creciente demanda de zonas protegidas con fines de desarrollo, que dificultan la labor de gestión de estas zonas. En el presente artículo, hemos analizado algunas de estas cuestiones con referencia a la India, a la vez que se hace más hincapié en el peligro que supone perder los servicios ecosistémicos (en su mayoría, de carácter intangible o regulador) que se derivan de estas zonas protegidas
Application priority framework for fixed mobile converged communication networks
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The current prospects in wired and wireless access networks, it is becoming increasingly important to address potential convergence in order to offer integrated broadband services. These systems will need to offer higher data transmission capacities and long battery life, which is the catalyst for an everincreasing variety of air interface technologies targeting local area to wide area connectivity. Current integrated industrial networks do not offer application aware context delivery and enhanced services for optimised networks. Application aware services provide value-added functionality to business applications by capturing, integrating, and consolidating intelligence about users and their endpoint devices from various points in the network. This thesis mainly intends to resolve the issues related to ubiquitous application aware service, fair allocation of radio access, reduced energy consumption and improved capacity. A technique that measures and evaluates the data rate demand to reduce application response time and queuing delay for multi radio interfaces is proposed. The technique overcomes the challenges of network integration, requiring no user intervention, saving battery life and selecting the radio access connection for the application requested by the end user. This study is split in two parts. The first contribution identifies some constraints of the services towards the application layer in terms of e.g. data rate and signal strength. The objectives are achieved by application controlled handover (ACH) mechanism in order to maintain acceptable data rate for real-time application services. It also looks into the impact of the radio link on the application and identifies elements and parameters like wireless link quality and handover that will influence the application type. It also identifies some enhanced traditional mechanisms such as distance controlled multihop and mesh topology required in order to support energy efficient multimedia applications. The second contribution unfolds an intelligent application priority assignment mechanism (IAPAM) for medical applications using wireless sensor networks. IAPAM proposes and evaluates a technique based on prioritising multiple virtual queues for the critical nature of medical data to improve instant transmission. Various mobility patterns (directed, controlled and random waypoint) has been investigated and compared by simulating IAPAM enabled mobile BWSN. The following topics have been studied, modelled, simulated and discussed in this thesis: 1. Application Controlled Handover (ACH) for multi radios over fibre 2. Power Controlled Scheme for mesh multi radios over fibre using ACH 3. IAPAM for Biomedical Wireless Sensor Networks (BWSN) and impact of mobility over IAPAM enabled BWSN. Extensive simulation studies are performed to analyze and to evaluate the proposed techniques. Simulation results demonstrate significant improvements in multi radios over fibre performance in terms of application response delay and power consumption by upto 75% and 15 % respectively, reduction in traffic loss by upto 53% and reduction in delay for real time application by more than 25% in some cases
Systematic approach to work-life balance research: theoretical development and empirical examination
No full textWork–life balance research has been extensively studied in Western contexts with
a focus on high-income and industrialized societies. However, it is not clear whether
this largely Western conceptualization of work–life balance, applying a segmentation-oriented perspective, would be applicable for employees working in fast-changing,
low-income, and/or pre-industrial societies. This thesis contributes to extant work–life
balance literature by theoretically advancing and empirically applying a systematic
approach to analyze the interactions between individuals’ work–life experiences and
their external environment, encompassing multiple social systems across the societal,
workplace, and micro levels. Specifically, I address the research aim of a systematic
analysis on the individuals’ work–life experiences and their multilevel social
environment by means of the following three studies:
Study 1 (see CHAPTER 3) undertakes a multi-disciplinary systematic literature
review and offers a systematic theoretical framework and future research agenda for
process-oriented, multilevel, and multidimensional analyses of work–life balance
support mechanisms. This review draws out the systematic and synergistic cooperation
between individuals and their environments in order to mobilize sufficient resources
for meeting individuals’ work–life demands and achieving better work–life balance.
Study 2 (see CHAPTER 4) offers a longitudinal quantitative study that examines
how work and parental demands and resources from workplace- and micro-level social
systems simultaneously shape the age-old but under-studied “time–money conundrum”
and how it may influence British working mothers’ work–life balance satisfaction and
job retention via three mechanisms: resource depletion, resource accumulation, and
resource investment.
Study 3 (see CHAPTER 5) is an exploratory qualitative study which advances a
holistic perspective of work–life balance and offers a systematic analytical framework
for explicating the contextualized relationships between societal development patterns
and people’s demands, resources, and work–life experiences in the specific context of
China through the lens of modernization theory. This holistic perspective underlines
work–life synergy and advocates living a satisfactory life that encompasses
complementary work and non-work accomplishments throughout the lifetime. This
approach is in contrast to the Western analytic, segmentation-oriented perspective that
dominates current work–life balance literature and focuses primarily on the pursuit of
minimal conflict between the two distinct spheres of work and personal life
Spatially-localized time dependent solutions including turbulence and their interactions in 2D Kolmogorov flow
No full textIn 2D Kolmogorov flow in small aspect ratio domains, spatially-localized solutions such as kink, traveling or time-dependent kink-antikink pars coexist. However, the conservation of the flow rate in the y direction strongly restrict combination of localized solutions and their positioning. We find that by adding a homogeneous flow U y their positioning is controlled and each of localized solutions including a spatially-localized chaos is isolated. Numerical results suggest that these isolated solutions can be elements constructing a whole flow
Characteristics of overlap region in high-Reynolds number turbulent channel flow
No full textDirect numerical simulation of the fully developed turbulent channel flows have been carried out at the Reynolds number based on the friction velocity and the channel half width, 2000, 4000 and 8000. A hybrid 10th order accurate finite difference scheme in the stream and spanwise directions, and a second-order scheme in the wall-normal direction is adapted as the spatial discretization method. We observed the plateau profiles in the indicator function corresponded to the von Karman constant. Furthermore, second peak of streamwise pre-multiplied spectra were appeared in the same wall normal height, 300 < y+ < 600, in case of Re = 4000. Nevertheless, the effects of the lager than the channel half height scale on the streamwise turbulent intensity are fixed contributions without dependence on Reynolds number. These results suggested that the new streamwise vortexes are formed between buffer layer and outer layer with increasing of Reynolds number
La 'circunstancia' de 'Herederos y Pretendientes
No full textIn June 2010, the Ortega y Gasset Foundation hosted a Conference about the “Spanish Philosophical Transition” in order to debate the book of Francisco Vázquez, La filosofía española. Herederos y Pretendientes. Una lectura sociológica (1963-1990), recently published. This paper is the author’s response to criticism raised in the Conference and to published reviews received by this book. First, the author summarized the argument of Herederos y pretendientes. Secondly he responds and takes into account the most important objections against the book’s hypothesis and methodology. Finally the author evaluates the favorable judgments received by the book and suggests the limits of the historian’s task.Fundación Ortega y Gasset-Marañó
Author self-citation in orthodontics is associated with author origin and gender.
No full textBACKGROUND
The aims of this bibliometric study were to determine author self-citation trends in high-impact orthodontic literature and to investigate possible association between self-citation and publication characteristics.
METHODS
Six orthodontic journals with the highest impact factor as ranked by 2017 Journal Citation Reports were screened for a full publication year (2018) for original research articles, reviews, and case reports. Eligible articles were scrutinized for article and author characteristics and citation metrics. Univariable and multivariable negative binomial regression was used to examine associations between self-citation incidence and publication characteristics.
RESULTS
Medians for author self-citation rate of the most self-citing authors and self-citations were 3.03% (range 0-50) and 1 (range 0-19), respectively. In the univariable analysis, there was no association between self-citation counts and study type (P = 0.41), article topic (P = 0.61), number of authors (P = 0.62), and rank of authors (P = 0.56). Author origin (P = 0.001), gender (P = 0.001) and journal (P = 0.05) were associated with self-citation counts and in the multivariable analysis only origin and gender remained strong self-citation predictors. Asian authors and females self-cited significantly less often than all other regions and male authors.
CONCLUSIONS
Authors in orthodontics do not self-cite at a frequency that suggests potential citation manipulation. Author origin and gender were the only variables associated with citations counts. More bibliometric research is necessary to draw solid conclusions about author self-citation trends in orthodontic literature
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