28 resultados para Transients and Migrants


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Understanding the cultural value systems of nations is a key factor in anticipating the behaviour of business managers and employees in a specific business environment. Many research studies have acknowledged the impact of culture on communication across nations and its impact on business operations, however no study has attempted to measure and quantify the cultural orientations of people originating from one nation, but working in two different national settings. This study adopted Kluckhohn and Strodtbeck's framework to examine cultural dimensions of a total of 580 Indian respondents comprising two groups: 429 Indian natives living and working in India and 151 Indian migrants living and working in the USA. It initially compares the cultural orientations of the total population of each of the two groups and then examines cultural differences in the same based on demographic characteristics consisting of occupation, gender, age, and level of education. The study found significant cultural value differences between the two groups on both levels of analysis. The theoretical and practical implications of these findings are discussed in detail.

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Liquid-liquid extraction has long been known as a unit operation that plays an important role in industry. This process is well known for its complexity and sensitivity to operation conditions. This thesis presents an attempt to explore the dynamics and control of this process using a systematic approach and state of the art control system design techniques. The process was studied first experimentally under carefully selected. operation conditions, which resembles the ranges employed practically under stable and efficient conditions. Data were collected at steady state conditions using adequate sampling techniques for the dispersed and continuous phases as well as during the transients of the column with the aid of a computer-based online data logging system and online concentration analysis. A stagewise single stage backflow model was improved to mimic the dynamic operation of the column. The developed model accounts for the variation in hydrodynamics, mass transfer, and physical properties throughout the length of the column. End effects were treated by addition of stages at the column entrances. Two parameters were incorporated in the model namely; mass transfer weight factor to correct for the assumption of no mass transfer in the. settling zones at each stage and the backmixing coefficients to handle the axial dispersion phenomena encountered in the course of column operation. The parameters were estimated by minimizing the differences between the experimental and the model predicted concentration profiles at steady state conditions using non-linear optimisation technique. The estimated values were then correlated as functions of operating parameters and were incorporated in·the model equations. The model equations comprise a stiff differential~algebraic system. This system was solved using the GEAR ODE solver. The calculated concentration profiles were compared to those experimentally measured. A very good agreement of the two profiles was achieved within a percent relative error of ±2.S%. The developed rigorous dynamic model of the extraction column was used to derive linear time-invariant reduced-order models that relate the input variables (agitator speed, solvent feed flowrate and concentration, feed concentration and flowrate) to the output variables (raffinate concentration and extract concentration) using the asymptotic method of system identification. The reduced-order models were shown to be accurate in capturing the dynamic behaviour of the process with a maximum modelling prediction error of I %. The simplicity and accuracy of the derived reduced-order models allow for control system design and analysis of such complicated processes. The extraction column is a typical multivariable process with agitator speed and solvent feed flowrate considered as manipulative variables; raffinate concentration and extract concentration as controlled variables and the feeds concentration and feed flowrate as disturbance variables. The control system design of the extraction process was tackled as multi-loop decentralised SISO (Single Input Single Output) as well as centralised MIMO (Multi-Input Multi-Output) system using both conventional and model-based control techniques such as IMC (Internal Model Control) and MPC (Model Predictive Control). Control performance of each control scheme was. studied in terms of stability, speed of response, sensitivity to modelling errors (robustness), setpoint tracking capabilities and load rejection. For decentralised control, multiple loops were assigned to pair.each manipulated variable with each controlled variable according to the interaction analysis and other pairing criteria such as relative gain array (RGA), singular value analysis (SVD). Loops namely Rotor speed-Raffinate concentration and Solvent flowrate Extract concentration showed weak interaction. Multivariable MPC has shown more effective performance compared to other conventional techniques since it accounts for loops interaction, time delays, and input-output variables constraints.

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The rodent ventrobasal (VB) thalamus receives sensory inputs from the whiskers and projects to the cortex, from which it receives reciprocal excitatory afferents. Much is known about the properties and functional roles of these glutamatergic inputs to thalamocortical neurons in the VB, but no data are available on how these afferents can affect thalamic glial cells. In this study, we used combined electrophysiological recordings and intracellular calcium ([Ca(2+)](i)) imaging to investigate glial cell responses to synaptic afferent stimulation. VB thalamus glial cells can be divided into two groups based on their [Ca(2+)](i) and electrophysiological responses to sensory and corticothalamic stimulation. One group consists of astrocytes, which stain positively for S100B and preferentially load with SR101, have linear current-voltage relations and low input resistance, show no voltage-dependent [Ca(2+)](i) responses, but express mGluR5-dependent [Ca(2+)](i) transients following stimulation of the sensory and/or corticothalamic excitatory afferent pathways. Cells of the other glial group, by contrast, stain positively for NG2, and are characterized by high input resistance, the presence of voltage-dependent [Ca(2+)](i) elevations and voltage-gated inward currents. There were no synaptically induced [Ca(2+)](i) elevations in these cells under control conditions. These results show that thalamic glial cell responses to synaptic input exhibit different properties to those of thalamocortical neurons. As VB astrocytes can respond to synaptic stimulation and signal to neighbouring neurons, this glial cell organization may have functional implications for the processing of somatosensory information and modulation of behavioural state-dependent thalamocortical network activities.

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Non-British migrants and their communities were an integral part of the multifaceted and multicultural nature of the British Empire. Their history, however, goes beyond a clearly delineated narrative of the Empire and includes transnational and truly global dimensions. German migrants and their transnational network creation within the structures of the British Empire, pursued over more than two centuries in a multitude of geographical settings, is the constitutive framework of the present volume. Eight contributions cover economic, cultural, scientific and political themes. The book questions traditional nation-centred narratives of the Empire as an exclusively British undertaking.

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What form is small business activity taking among new migrants in the UK? This question is addressed by examining the case of Somalis in the English city of Leicester.We apply a novel synthesis of the Nee and Sanders' (2001) `forms of capital' model with the `mixed embeddedness' approach (Rath, 2000) to enterprises established by newly arrived immigrant communities, combining agency and structure perspectives. Data are drawn from business-owners (and workers) themselves, rather than community representatives. Face-to-face in-depth interviews were held with 25 business owners and 25 employees/`helpers', supplemented by 3 focus group encounters with different segments of the Somali business population.The findings indicate that a reliance solely on social capital explanations is not sufficient. An adequate understanding of business dynamics requires an appreciation of how Somalis mobilize different forms of capital within a given political, social and economic context.

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Mixing phenomena observed when the flow rate in a single loop of the primary circuit is changed can influence the operation of pressurized water reactor (PWR) by inducing local gradients of boron concentration or coolant temperature. Analysis of one-dimensional Laser Doppler Anemometry (LDA) measurements during the start-up and shutdown of pump on a single loop of the ROCOM test facility has been performed. The effect of a step change and a ramped change in the flow rate on the axial and azimuthal velocities was examined. Numerical simulations were also performed for the step change in the flow rate that gave quantitative agreement with the axial velocities. Phenomenological agreement was made on the turbulent kinetic energy; however, observed values were a factor of 2.5 less than the turbulent kinetic energy derived from the measurements. © 2007.

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This thesis studies the links between language, migration and integration in the context of the 'new migrant' group of Latin Americans in London. It reviews the many ways in which language impacts the integration processes of migrants by influencing people's access to jobs, services, social contacts and information. By focusing on migrants' experiences this research also investigates the ways in which language and identity articulate, as well as the affective variables that are at play in the acquisition of the local language. With a large sector trapped in a cycle of poor command of English and labour market disadvantage, many Latin Americans experience exclusion and poverty. In reaction to this, a sector of the community is campaigning for ethnic minority recognition. This work reviews the debates for recognition and the strategy of organising around ethnicity, paying special attention to the role language plays in the process. The study is based on over two and half years of qualitative research, which included interviews, surveys, and long-term participant observation within a community organisation and a recognition campaign. Its interdisciplinary perspective allows the recognition of both the intimate links between language and identity, as well as the social and structural forces that influence migrants' linguistic integration. It unveils the practical and symbolic value that the mother tongue has for Latin American migrants and provides a broader account of their experiences. This research calls attention to the need for a more comprehensive approach to the study of language and migration in order to acknowledge the affective and social factors involved in the linguistic practices of migrants. By studying the community's struggles for recognition, this work evidences both the importance of visibility for minority groups in London and the intrinsic methodological limitations of monitoring through ethnic categorisation.

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Two decades after Japanese-Peruvians and other South Americans of Japanese descent began to migrate back to Japan, the return-migration phenomenon has ended. Induced by the Japanese government in the name of shared ethnicity, Japanese policymakers now largely regard return migration as a failed policy. It failed because return-migrants did not, in the view of policy- makers, assimilate, integrate, or “make it” in Japan as expected. Thus, once-imagined ethnic bonds ceased to exist in Japan. However, ethnic bonds sustained themselves well outside Japan. The Japanese-Peruvian community in Peru has thrived and maintained continuous ties with Japan. What explains the rise and fall of diasporic ethnic bonds? Drawing on my ethnographic research in Japanese-Peruvian communities in Peru and Japan, I found that diasporic ethnic bonds are cultivated or weakened depending upon where diasporic populations are located in relation to their ancestral homeland, and how such ties are utilized, for what, and by whom.

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This chapter employs Pnina Werbner's notion of diasporas as moral communities of suffering and co-responsibility, as well as aesthetic communities of shared transnational consumption of culture and performance of ritual, and relates this to the case of Tamil migrants of diverse state origins in Britain. Sri Lankan Tamil migrants I interviewed towards my research imagine membership of a Tamil diaspora as based on personal (or familial) experiences of suffering in the Sri Lankan civil war, which acts both to create bonds with other Sri Lankan Tamils, and to distinguish from Tamils of other state origins (Indian, Singaporean etc.) despite cultural commonalities (Werbner's aesthetic diaspora). Conversely, many of the non-Sri Lankan Tamil migrants I interviewed imagined these boundaries in more flexible terms, and claimed membership of the 'community of suffering' in ways which did not necessitate personal experience, but rather privileged symbolic constructions of the ethnic community, and an interpretation of historical and current events in India, Sri Lanka (and other sites of Tamil population) as components of a single narrative of Tamil victimhood.

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Focusing on former-Soviet Greeks' experiences of cross-border movement to Greece, this paper sheds light on the impact of this migration on the social identities of Russian Greeks as a transnational community. It draws on informants’ narratives and ethnographic observations recorded among Greek migrants in their home communities in southern Russia, and shows how their motivation, in their transnational movement, is determined by the ‘push-and-pull’ forces of socio-economic and political transformations in post-Soviet space. In these conditions, Greek identity becomes a resource which facilitates the organisation of transnational migration. The cultural, social and economic differences between the former-Soviet Greek migrants and the native-born population of Greece result in the emergence of a Pontic-Greek cultural identity which emphasises migrants’ connections with the former USSR. The difficulties of economic and cultural adaptation for migrants to Greece are examined in relation to the Russian Greeks' economic strategies within their home communities and their perception of the ‘homeland’ as a constantly contested and relocated social construct.

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Potentiostatically induced current transients obtained on a range of reinforced concrete specimens were analysed to give estimates of the polarisation resistance and interfacial capacitance. The polarisation resistance was compared with the values obtained using more conventional DC methods of analysis and, while it was consistently lower, it was within the error normally attributed to the polarisation resistance method of corrosion rate determination. The interfacial capacitance values determined increased from 0.44 F m -2 for passive steel (polarisation resistance of 132 Ω m 2) to 26.5 F m -2 for active steel (polarisation resistance of 0.34 Ω m 2). This has a dominant effect on the time required for potentiostatically induced current transients to reach a steady state with a longer time being required by actively corroding steel. By contrast the potential decay time constants describing galvanostatically or coulostatically induced potential transients decrease with an increase in corrosion rate and values less than 25 s for active specimens and greater than 40 s for passive specimens were determined in this work. © 1997 Elsevier Science Ltd.

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German migrants were to be found in significant numbers in the British hospitality industry during the period 1880 to 1920. They worked as waiters, chefs, and managers of restaurants and hotels. This article has three main sections. It begins with a brief outline of the rise of restaurants and hotels in late nineteenth-century Britain and the role of migrants in this process. It then analyses the Germans in the British hospitality industry in the decades leading up to the First World War. The article then focuses upon the rise of hostility towards Germans with the approach of the Great War, which led to dismissal, internment and repatriation during the conflict.

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This book addresses the issue of emerging transnationalism in the conditions of post-socialism through focussing on migrants’ identity as a social construction resulting from their experience of the ‘transnational circuit of culture’ as well as from post-Soviet shifts in political and economic conditions in their home regions. Popov draws upon ethnographic research conducted among Greek transnational migrants living on the Black Sea coast and in the North Caucasus regions of Russia who have become involved in extensive cross-border migration between the former Soviet Union (the Russian Federation, Kazakhstan and Georgia) and Greece (as well as Cyprus). It is estimated that more than 150,000 former Soviet citizens of Greek origin have resettled in Greece since the late 1980s. Yet, many of those who emigrate do not cut their connections with the home communities in Russia but instead establish their own transnational circuit of travel between Greece and Russia. This study demonstrates how migrants employ their ethnicity as symbolic capital available for investment in profitable transnational migration. Simultaneously they rework their practices of family networking, property relations and political participation in a way which strengthens their attachment to the local territory. The findings presented in the book imply that the social identities, economic strategies, political practices and cultural representation of the Russian Greeks are all deeply embedded in the shifting social and cultural landscape of post-Soviet Russia and extensively influenced by the global movement of ideas, goods and people.