872 resultados para dynamic and static qualities


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A collection of versatile best practices for promoting literacy development by utilizing local community connections in school and public libraries. This book provides a fresh approach to learning as well as guidelines for creating dynamic and relevant library programs for children, teens, and families. Organized thematically, each chapter includes relevant topical research and three to eight community-focused approaches. Programs range from small, single-library initiatives in rural communities to multi-site, cross-border initiatives. This resource includes collaborative and locally inspired programs, many of which can be scaled to the budget of any library, school, or community organization.

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Integrated interpretation of multi-beam bathymetric, sediment-penetrating acoustic (PARASOUND) and seismic data show a multiple slope failure on the northern European continental margin, north of Spitsbergen. The first slide event occurred during MIS 3 around 30 cal. ka BP and was characterised by highly dynamic and rapid evacuation of ca. 1250 km**3 of sediment from the lower to the upper part of the continental slope. During this event, headwalls up to 1600 m high were created and ca. 1150 km**3 material from hemi-pelagic sediments and from the lower pre-existing trough mouth fan has been entrained and transported into the semi-enclosed Sophia Basin. This megaslide event was followed by a secondary evacuation of material to the Nansen Basin by funnelling of the debris through the channel between Polarstern Seamount and the adjacent continental slope. The main slide debris is overlain by a set of fining-upward sequences as evidence for the associated suspension cloud and following minor failure events. Subsequent adjustment of the eastern headwalls led to failure of rather soft sediments and creation of smaller debris flows that followed the main slide surficial topography. Discharge of the Hinlopen ice stream during the Last Glacial Maximum and the following deglaciation draped the central headwalls and created a fan deposit of glacigenic debris flows.

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We Are the Ones We Have Been Waiting for: Pan-African Consciousness Raising and Organizing in the United States and Venezuela, draws on fifteen months of field research accompanying organizers, participating in protests, planning/strategy meetings, state-run programs, academic conferences and everyday life in these two countries. Through comparative examination of the processes by which African Diaspora youth become radically politicized, this work deconstructs tendencies to deify political s/heroes of eras past by historicizing their ascent to political acclaim and centering the narratives of present youth leading movements for Black/African liberation across the Diaspora. I employ Manuel Callahan’s description of “encuentros”, “the disruption of despotic democracy and related white middle-class hegemony through the reconstruction of the collective subject”; “dialogue, insurgent learning, and convivial research that allows for a collective analysis and vision to emerge while affirming local struggles” to theorize the moments of encounter, specifically, the moments (in which) Black/African youth find themselves becoming politically radicalized and by what. I examine the ways in which Black/African youth organizing differs when responding to their perpetual victimization by neoliberal, genocidal state-politics in the US, and a Venezuelan state that has charged itself with the responsibility of radically improving the quality of life of all its citizens. Through comparative analysis, I suggest the vertical structures of “representative democracy” dominating the U.S. political climate remain unyielding to critical analyses of social stratification based on race, gender, and class as articulated by Black youth. Conversely, I contend that present Venezuelan attempts to construct and fortify more horizontal structures of “popular democracy” under what Hugo Chavez termed 21st Century Socialism, have resulted in social fissures, allowing for a more dynamic and hopeful negation between Afro-Venezuelan youth and the state.

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Effective conservation and management of top predators requires a comprehensive understanding of their distributions and of the underlying biological and physical processes that affect these distributions. The Mid-Atlantic Bight shelf break system is a dynamic and productive region where at least 32 species of cetaceans have been recorded through various systematic and opportunistic marine mammal surveys from the 1970s through 2012. My dissertation characterizes the spatial distribution and habitat of cetaceans in the Mid-Atlantic Bight shelf break system by utilizing marine mammal line-transect survey data, synoptic multi-frequency active acoustic data, and fine-scale hydrographic data collected during the 2011 summer Atlantic Marine Assessment Program for Protected Species (AMAPPS) survey. Although studies describing cetacean habitat and distributions have been previously conducted in the Mid-Atlantic Bight, my research specifically focuses on the shelf break region to elucidate both the physical and biological processes that influence cetacean distribution patterns within this cetacean hotspot.

In Chapter One I review biologically important areas for cetaceans in the Atlantic waters of the United States. I describe the study area, the shelf break region of the Mid-Atlantic Bight, in terms of the general oceanography, productivity and biodiversity. According to recent habitat-based cetacean density models, the shelf break region is an area of high cetacean abundance and density, yet little research is directed at understanding the mechanisms that establish this region as a cetacean hotspot.

In Chapter Two I present the basic physical principles of sound in water and describe the methodology used to categorize opportunistically collected multi-frequency active acoustic data using frequency responses techniques. Frequency response classification methods are usually employed in conjunction with net-tow data, but the logistics of the 2011 AMAPPS survey did not allow for appropriate net-tow data to be collected. Biologically meaningful information can be extracted from acoustic scattering regions by comparing the frequency response curves of acoustic regions to theoretical curves of known scattering models. Using the five frequencies on the EK60 system (18, 38, 70, 120, and 200 kHz), three categories of scatterers were defined: fish-like (with swim bladder), nekton-like (e.g., euphausiids), and plankton-like (e.g., copepods). I also employed a multi-frequency acoustic categorization method using three frequencies (18, 38, and 120 kHz) that has been used in the Gulf of Maine and Georges Bank which is based the presence or absence of volume backscatter above a threshold. This method is more objective than the comparison of frequency response curves because it uses an established backscatter value for the threshold. By removing all data below the threshold, only strong scattering information is retained.

In Chapter Three I analyze the distribution of the categorized acoustic regions of interest during the daytime cross shelf transects. Over all transects, plankton-like acoustic regions of interest were detected most frequently, followed by fish-like acoustic regions and then nekton-like acoustic regions. Plankton-like detections were the only significantly different acoustic detections per kilometer, although nekton-like detections were only slightly not significant. Using the threshold categorization method by Jech and Michaels (2006) provides a more conservative and discrete detection of acoustic scatterers and allows me to retrieve backscatter values along transects in areas that have been categorized. This provides continuous data values that can be integrated at discrete spatial increments for wavelet analysis. Wavelet analysis indicates significant spatial scales of interest for fish-like and nekton-like acoustic backscatter range from one to four kilometers and vary among transects.

In Chapter Four I analyze the fine scale distribution of cetaceans in the shelf break system of the Mid-Atlantic Bight using corrected sightings per trackline region, classification trees, multidimensional scaling, and random forest analysis. I describe habitat for common dolphins, Risso’s dolphins and sperm whales. From the distribution of cetacean sightings, patterns of habitat start to emerge: within the shelf break region of the Mid-Atlantic Bight, common dolphins were sighted more prevalently over the shelf while sperm whales were more frequently found in the deep waters offshore and Risso’s dolphins were most prevalent at the shelf break. Multidimensional scaling presents clear environmental separation among common dolphins and Risso’s dolphins and sperm whales. The sperm whale random forest habitat model had the lowest misclassification error (0.30) and the Risso’s dolphin random forest habitat model had the greatest misclassification error (0.37). Shallow water depth (less than 148 meters) was the primary variable selected in the classification model for common dolphin habitat. Distance to surface density fronts and surface temperature fronts were the primary variables selected in the classification models to describe Risso’s dolphin habitat and sperm whale habitat respectively. When mapped back into geographic space, these three cetacean species occupy different fine-scale habitats within the dynamic Mid-Atlantic Bight shelf break system.

In Chapter Five I present a summary of the previous chapters and present potential analytical steps to address ecological questions pertaining the dynamic shelf break region. Taken together, the results of my dissertation demonstrate the use of opportunistically collected data in ecosystem studies; emphasize the need to incorporate middle trophic level data and oceanographic features into cetacean habitat models; and emphasize the importance of developing more mechanistic understanding of dynamic ecosystems.

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This thesis addresses how Alexis de Tocqueville’s political thought is related to American Exceptionalism. First, I illustrate the multiple meanings of the concept of American Exceptionalism and in what sense it is indebted to Tocqueville. Second, I articulate how the historical background and personal qualities of Tocqueville contribute to the success of his masterpiece Democracy in America. In the main part, by analyzing Tocqueville’s Democracy in America and other writings on America, I argue that he indeed reveals America as exceptional and increasingly recognizes this idea through a process of intellectual development. An elaboration on Tocqueville’s theoretical contribution to the discussion of American Exceptionalism can reveal the different images of modern democracy as he suggests and how they would influence the prospect of human freedom.

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Le but de cette thèse est d’explorer le potentiel sismique des étoiles naines blanches pulsantes, et en particulier celles à atmosphères riches en hydrogène, les étoiles ZZ Ceti. La technique d’astérosismologie exploite l’information contenue dans les modes normaux de vibration qui peuvent être excités lors de phases particulières de l’évolution d’une étoile. Ces modes modulent le flux émergent de l’étoile pulsante et se manifestent principalement en termes de variations lumineuses multi-périodiques. L’astérosismologie consiste donc à examiner la luminosité d’étoiles pulsantes en fonction du temps, afin d’en extraire les périodes, les amplitudes apparentes, ainsi que les phases relatives des modes de pulsation détectés, en utilisant des méthodes standards de traitement de signal, telles que des techniques de Fourier. L’étape suivante consiste à comparer les périodes de pulsation observées avec des périodes générées par un modèle stellaire en cherchant l’accord optimal avec un modèle physique reconstituant le plus fidèlement possible l’étoile pulsante. Afin d’assurer une recherche optimale dans l’espace des paramètres, il est nécessaire d’avoir de bons modèles physiques, un algorithme d’optimisation de comparaison de périodes efficace, et une puissance de calcul considérable. Les périodes des modes de pulsation de modèles stellaires de naines blanches peuvent être généralement calculées de manière précise et fiable sur la base de la théorie linéaire des pulsations stellaires dans sa version adiabatique. Afin de définir dans son ensemble un modèle statique de naine blanche propre à l’analyse astérosismologique, il est nécessaire de spécifier la gravité de surface, la température effective, ainsi que différents paramètres décrivant la disposition en couche de l’enveloppe. En utilisant parallèlement les informations obtenues de manière indépendante (température effective et gravité de surface) par la méthode spectroscopique, il devient possible de vérifier la validité de la solution obtenue et de restreindre de manière remarquable l’espace des paramètres. L’exercice astérosismologique, s’il est réussi, mène donc à la détermination précise des paramètres de la structure globale de l’étoile pulsante et fournit de l’information unique sur sa structure interne et l’état de sa phase évolutive. On présente dans cette thèse l’analyse complète réussie, de l’extraction des fréquences à la solution sismique, de quatre étoiles naines blanches pulsantes. Il a été possible de déterminer les paramètres structuraux de ces étoiles et de les comparer remarquablement à toutes les contraintes indépendantes disponibles dans la littérature, mais aussi d’inférer sur la dynamique interne et de reconstruire le profil de rotation interne. Dans un premier temps, on analyse le duo d’étoiles ZZ Ceti, GD 165 et Ross 548, afin de comprendre les différences entre leurs propriétés de pulsation, malgré le fait qu’elles soient des étoiles similaires en tout point, spectroscopiquement parlant. L’analyse sismique révèle des structures internes différentes, et dévoile la sensibilité de certains modes de pulsation à la composition interne du noyau de l’étoile. Afin de palier à cette sensibilité, nouvellement découverte, et de rivaliser avec les données de qualité exceptionnelle que nous fournissent les missions spatiales Kepler et Kepler2, on développe une nouvelle paramétrisation des profils chimiques dans le coeur, et on valide la robustesse de notre technique et de nos modèles par de nombreux tests. Avec en main la nouvelle paramétrisation du noyau, on décroche enfin le ”Saint Graal” de l’astérosismologie, en étant capable de reproduire pour la première fois les périodes observées à la précision des observations, dans le cas de l’étude sismique des étoiles KIC 08626021 et de GD 1212.

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This Special Issue of The Holocene contains 16 research papers based on a symposium at the 11th International Meeting of the European Union of Geosciences held in Strasbourg in April 2001. The aim of the symposium was a state-of-the-art assessment of empirical studies of postglacial marine and terrestrial climatic archives and their integration with numerical climate models. This editorial places the individual papers in the broader context of natural climate variability and anthropogenic impacts on the global climate system, regional differences in climate between maritime and continental areas, and the need for an improved theoretical basis for understanding the underlying causes of environmental change. The focus of the Special Issue is the dynamic and relatively well-understood climate of the North Atlantic and the European realm, where, in relation to the steepest offshore temperature gradient on Earth, observational data are abundant and many recent advances have been made in climate reconstruction from proxy archives. The editorial also contains a summary and overview of the papers included in the four main sections of the Special Issue, which emphasize: (1) numerical modelling experiments; (2) models of glacier buildup and equilibrium-line altitude; (3) marine and terrestrial proxy records of climatic change; and (4) multiproxy palaeoenvironmental reconstruction of a Portuguese lagoonal system.

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Urban regions worldwide are increasingly facing the challenge of dealing with highly dynamic metropolitan growth and, at the same time, institutional changes like decentralisation and globalisation. These kinds of changes express themselves most evidently in peri-urban areas, where urban and rural life meets. These peri-urban areas in particular have been the stage for rapid physical, social and economic transformations, both in developed and developing countries. Peri-urbanization takes place here. Based on literature review, this paper presents an effort to identify generic attributes of peri-urbanisation and the way in which development planning tends to reply. Three major attributes are identified: peri-urban space (the spatial expression of peri-urban development), peri-urban life (the functional appearance of land uses, activities and peri-urban innovation), and peri-urban change (a causal and temporal perspective featuring flows and drivers of change). It is also shown that prevalent institutional replies in planning and development generally fail to acknowledge the dynamic and increasingly fragmented attributes of global peri-urbanisation.

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Graphene, with its unique electronic and structural qualities, has become an important playground for studying adsorption and assembly of various materials including organic molecules. Moreover, organic/graphene vertical structures assembled by van der Waals interaction have potential for multifunctional device applications. Here, we investigate structural and electrical properties of vertical heterostructures composed of C60 thin film on graphene. The assembled film structure of C60 on graphene is investigated using transmission electron microscopy, which reveals a uniform morphology of C60 film on graphene with a grain size as large as 500 nm. The strong epitaxial relations between C60 crystal and graphene lattice directions are found, and van der Waals ab initio calculations support the observed phenomena. Moreover, using C60-graphene heterostructures, we fabricate vertical graphene transistors incorporating n-type organic semiconducting materials with an on/off ratio above 3 × 10(3). Our work demonstrates that graphene can serve as an excellent substrate for assembly of molecules, and attained organic/graphene heterostructures have great potential for electronics applications.

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Permanent magnet synchronous motors (PMSMs) provide a competitive technology for EV traction drives owing to their high power density and high efficiency. In this paper, three types of interior PMSMs with different PM arrangements are modeled by the finite element method (FEM). For a given amount of permanent magnet materials, the V-shape interior PMSM is found better than the U-shape and the conventional rotor topologies for EV traction drives. Then the V-shape interior PMSM is further analyzed with the effects of stator slot opening and the permanent magnet pole chamfering on cogging torque and output torque performance. A vector-controlled flux-weakening method is developed and simulated in Matlab to expand the motor speed range for EV drive system. The results show good dynamic and steady-state performance with a capability of expanding speed up to four times of the rated. A prototype of the V-shape interior PMSM is also manufactured and tested to validate the numerical models built by the FEM.

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This paper aims to investigate the Business Administration professional profile specifically required to manage innovative and high technology-based companies. It is a qualitative study outlined by an exploratory-descriptive research, supported by questionnaires and interviews addressed to a sample of executives of technology-based companies, located in São Paulo metropolitan region, Brazil. Accordingly, modular innovation arises from the existence of an architectural knowledge improved in association with the conceptually destroyed knowledge's component, meaning that architectural innovation arises from an improvement in the knowledge of the parties allied to the architectural knowledge's destruction. Results show that managers see innovation as one essential pillar for competitiveness and commonly associate innovation with team expertise related with the structure for this purpose. However, to instill innovation as an organizational discipline, it is necessary to redesign organizational processes, namely those considered critical to innovate. The company must revise its management model aiming to emphasize innovative behavior, which means readiness to respond to external environment change's requirements. Moreover, once it is necessary to change the manager's mindset about innovation, higher education institutions also have to adapt their Business Administration courses according to both changes, essentially concerning a more dynamic and more diffuse business environment in comparison to their curricular contents. The institutional pragmatism generates professionals who reach the job market with a historical and non-managerial overview on innovation. Nevertheless, results highlight that attitude is more appreciated than knowledge, or business management skills, what makes managerial behavior a key element in the innovation process in technology-based firms.

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As the world`s population is constantly growing, food security will remain on the policy Agenda, particularly in Africa. At the same time, global food systems experience a new wave focusing on local foods and food sovereignty featuring high quality food products of verifiable geographical origin. This article argues that Geographical Indications (GI´s) hold the potential to help transform the Tanzanian agriculture-dependent economy through the tapping of value from unique products, attributing taste and colour to place or regional geography. This study aims to identify the existence and characteristics of food origin products in Tanzania that have potential for GI certification. The hypothesis was that there are origin products in Tanzania whose unique characteristics are linked to the area of production. Geographical indications can be useful policy instruments contributing to food security and sovereignty and quality within an efficient marketing system with the availability of government support, hence the need to identify key candidates for GI certification. Five Tanzanian origin products were selected from 14 candidate agricultural products through a scoping study. Rice from Kyela, Aloe vera, Coffee and Sugar from Kilimanjaro and Cloves from Zanzibar are some of the product cases investigated and provides for in-depth case study, as ´landscape´ products incorporating ´taste of place´. Interviews were conducted to collect quantitative and qualitative data. Data was collected on the production area, product quality perceived by the consumer in terms of taste, flavour, texture, aroma, appearance (colour, size) and perceptions of links between geography related factors (soil, land weather characteristics) and product qualities. A qualitative case study analysis was done for each of the (five) selected Tanzanian origin products investigated with plausible prospects for Tanzania to leapfrog into exports of Geographical Indications products. Framework conditions for producers creating or capturing market value as stewards of cultural and landscape values, environments, and institutional requirements for such creation or capturing to happen, including presence of export opportunities, are discussed. Geographical indication is believed to allow smallholders to create employment and build monetary value, while stewarding local food cultures and natural environments and resources, and increasing the diversity of supply of natural and unique quality products and so contribute to enhanced food security.

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The mammalian binaural cue of interaural time difference (ITD) and cross-correlation have long been used to determine the point of origin of a sound source. The ITD can be defined as the different points in time at which a sound from a single location arrives at each individual ear [1]. From this time difference, the brain can calculate the angle of the sound source in relation to the head [2]. Cross-correlation compares the similarity of each channel of a binaural waveform producing the time lag or offset required for both channels to be in phase with one another. This offset corresponds to the maximum value produced by the cross-correlation function and can be used to determine the ITD and thus the azimuthal angle θ of the original sound source. However, in indoor environments, cross-correlation has been known to have problems with both sound reflections and reverberations. Additionally, cross-correlation has difficulties with localising short-term complex noises when they occur during a longer duration waveform, i.e. in the presence of background noise. The crosscorrelation algorithm processes the entire waveform and the short-term complex noise can be ignored. This paper presents a technique using thresholding which enables higher-localisation abilities for short-term complex sounds in the midst of background noise. To determine the success of this thresholding technique, twenty-five sounds were recorded in a dynamic and echoic environment. The twenty-five sounds consist of hand-claps, finger-clicks and speech. The proposed technique was compared to the regular cross-correlation function for the same waveforms, and an average of the azimuthal angles determined for each individual sample. The sound localisation ability for all twenty-five sound samples is as follows: average of the sampled angles using cross-correlation: 44%; cross-correlation technique with thresholding: 84%. From these results, it is clear that this proposed technique is very successful for the localisation of short-term complex sounds in the midst of background noise and in a dynamic and echoic indoor environment.

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In this paper, we examine the on-the-ground realities of upstream-downstream negotiations and transactions over ecosystem services. We explore the engagement, negotiation, implementation, and postimplementation phases of a “reciprocal water access” (RWA) agreement between village communities and municipal water users at Palampur, Himachal Pradesh, India. We aim to highlight how external actors drove the payments for ecosystem services agenda through a series of facilitation and research engagements, which were pivotal to the RWA’s adoption, and how the agreement fared once external agents withdrew. In the postimplementation period, the RWA agreement continues to be upheld by upstream communities amidst evolving, competing land-use changes and claims. The introduction of cash payments for environmental services for forest-water relationships has given rise to multifaceted difficulties for the upstream hamlets, which has impeded the functionality of their forest management committee. Upstream communities’ formal rights and abilities to control and manage their resources are dynamic and need strengthening and assurance; these developments result in fluctuating transaction and opportunity costs not originally envisaged by the RWA agreement. The paper demonstrates the importance of an explicit understanding of the local politics of negotiation and implementation to determine the effectiveness of compensation-based mechanisms for the supply of ecosystem services.

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This article examines European Union (EU) approaches to the question of human rights violations in Kosovo before and after its proclamation of independence, in February 2008. While the 1999 NATO-led humanitarian intervention in the region was often justified as necessary due to the continuous abuses of human rights, perpetrated by the Serbian forces against the ethic Kosovo Albanians, the post-interventionist period has witnessed a dramatic reversal of roles, with the rights of the remaining Serbian minority being regularly abused by the dominant Albanian population. However, in contrast to the former scenario, the Brussels administration has remained quite salient about the post-independence context – a grey zone of unviable political and social components, capable of generating new confrontations and human rights abuses within the borders of Kosovo. Aware of this dynamic and the existing EU official rhetoric, it is possible to conclude that the embedded human rights concerns in Kosovo are not likely to disappear, but even more importantly, their relevance has been significantly eroded.