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Destination
Kinds of Destination Terms modified by Destination Selected AbstractsTHE JOINT CHOICE OF AN INDIVIDUAL'S OCCUPATION AND DESTINATION,JOURNAL OF REGIONAL SCIENCE, Issue 5 2008Christiadi ABSTRACT This study examines the relationship between an individual's occupation choice and destination choice. It portrays the relationship as an interaction between the supply of occupational skills by individuals and demand by different labor-market regions. The unusual merger of a multinomial logit model of occupational choice and the conditional logit model of destination choice in a simultaneous equation framework requires derivation of a unique variance,covariance matrix. Results indicate strong association between supply of (migration) and demand for (industry mix) an individual's occupational skills. These effects are especially strong for destinations experiencing slow economic growth, while relatively unimportant for high-growth locations. [source] FIRM EFFICIENCY AND THE DESTINATION OF EXPORTS: EVIDENCE FROM KENYAN PLANT-LEVEL DATATHE DEVELOPING ECONOMIES, Issue 3 2009Mats GRANÉR D24; F14; L60; O24; O33 Investigating the link between firm efficiency and exports in Kenyan manufacturing, the results show that exporters are more efficient than non-exporters, and that relatively efficient firms self-select into exporting. An important new finding is that only for export markets outside Africa must firms be efficient prior to entry. The probability of exporting to other African countries increases if production is intense in physical and human capital. For export activities outside Africa, firm size is more important. Contrary to many other studies, it is also found that export participation yields learning effects. When testing the hypothesis that the main source of learning effects is trade with developed countries (south,north), as opposed to trade with other developing countries (south,south), yet another new finding is that learning effects only obtain in south,south trade. Therefore, one can conclude that controlling for the destination of exports importantly improves the understanding of the relationship between firm efficiency and exports. [source] SUBURBANIZATION IN COUNTRIES IN TRANSITION: DESTINATIONS OF SUBURBANIZERS IN THE TALLINN METROPOLITAN AREAGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 2 2007Kadri Leetmaa ABSTRACT. Suburbanization is one of the key phenomena of spatial population change in many countries in transition. Yet we know surprisingly little about the population carrying out the post-socialist suburbanization process. The objective of this article is to improve on this situation by studying the Tallinn metropolis in Estonia. Our analysis, which covers the inter-censal period 1989 to 2000, focuses on the differences between population subgroups with respect to their probabilities to move to the suburbs. As such, it also clarifies choices of destination by dwelling and municipality type. For the analysis, we use individual anonymous 2000 census data and logistic regression. The results indicate that suburbanization was a socially polarizing process during this period. People with low social status had the highest probability to sub-urbanize, and mainly occupied the pre-existing housing stock. Conversely, people with high social status were less likely to move into suburban areas, yet when they did they moved to the most attractive destinations in the suburbs (new single-family houses, coastal municipalities and municipalities closer to the city). [source] Destination-based seed dispersal homogenizes genetic structure of a tropical palmMOLECULAR ECOLOGY, Issue 8 2010JORDAN KARUBIAN Abstract As the dominant seed dispersal agents in many ecosystems, frugivorous animals profoundly impact gene movement and fine-scale genetic structure of plants. Most frugivores engage in some form of destination-based dispersal, in that they move seeds towards specific destinations, resulting in clumped distributions of seeds away from the source tree. Molecular analyses of dispersed seeds and seedlings suggest that destination-based dispersal may often yield clusters of maternal genotypes and lead to pronounced local genetic structure. The long-wattled umbrellabird Cephalopterus penduliger is a frugivorous bird whose lek mating system creates a species-specific pattern of seed dispersal that can potentially be distinguished from background dispersal processes. We used this system to test how destination-based dispersal by umbrellabirds into the lek affects gene movement and genetic structure of one of their preferred food sources Oenocarpus bataua, a canopy palm tree. Relative to background dispersal processes, umbrellabird mating behaviour yielded more diverse seed pools in leks that included on average five times more seed sources and a higher incidence of long-distance dispersal events. This resulted in markedly lower fine-scale spatial genetic structure among established seedlings in leks than background areas. These species-specific impacts of destination-based dispersal illustrate how detailed knowledge of disperser behaviour can elucidate the mechanistic link driving observed patterns of seed movement and genetic structure. [source] Mothers' Parenting Cognitions in Cultures of Origin, Acculturating Cultures, and Cultures of DestinationCHILD DEVELOPMENT, Issue 1 2004Marc H. Bornstein Japanese and South American immigrant mothers' parenting cognitions (attributions and self-perceptions) were compared with mothers from their country of origin (Japan and Argentina, respectively) and European American mothers in the United States. Participants were 231 mothers of 20-month-old children. Generally, South American immigrant mothers' parenting cognitions more closely resembled those of mothers in the United States, whereas Japanese immigrant mothers' cognitions tended to be similar to those of Japanese mothers or intermediate between Japanese and U.S. mothers. This study provides insight into the nature of parenting cognitions generally and those of immigrant mothers specifically and therefore the parenting climate in which immigrant children are reared. [source] Dominican Immigrants and Discrimination in a New Destination: The Case of Reading, PennsylvaniaCITY & COMMUNITY, Issue 3 2010R.S. Oropesa The last decade has witnessed the diversification of immigrant destinations in the United States. Although the literature on this phenomenon is burgeoning, research on the experiences of smaller immigrant groups in new destinations is underdeveloped. This is especially the case for those from the Dominican Republic, a group that is expanding beyond the traditional gateway cities of the Northeast. Using a survey of Dominican immigrants in Reading, Pennsylvania, this study has two objectives. The first objective is to describe the prevalence of experiences with institutional and interpersonal discrimination. The second objective is to determine the extent to which these experiences are structured around racial markers (i.e., skin tone), forms of capital, forms of incorporation, and exposure to the United States. Our results show that a substantial minority of Dominican immigrants claims to have been treated unfairly, primarily because of their "race and ethnicity." In addition, experiences with some types of discrimination are positively associated with skin tone (i.e., darkness) and several factors that are identified in models of assimilation. Los inmigrantes dominicanos y sus experiencias con la discriminación en un nuevo lugar de destino: el caso de Reading, Pennsylvania (R.S. Oropesa y Leif Jensen) Resumen En la última década, se ha dado un proceso de diversificación de los lugares de destino en la migración a los Estados Unidos. Aún cuando la literatura sobre el tema está aumentando, todavía sabemos muy poco sobre las experiencias de los grupos más pequeños de inmigrantes en nuevos lugares de destino. Esto ocurre especialmente con la comunidad inmigrante de la República Dominicana, un grupo que se está expandiendo más allá de las ciudades de entrada tradicionales en el Noreste del país. El presente estudio hace uso de una encuesta con inmigrantes dominicanos en Reading, Pennsylvania para cumplir con los siguientes objetivos. El primer objetivo es describir la preponderancia de las experiencias de discriminación tanto institucional como interpersonal en dicha comunidad. El segundo objetivo es determinar hasta qué punto estas experiencias están relacionadas con indicadores raciales (por ejemplo, color de la piel), tipos de capital, modos de incorporación y contacto previo con los Estados Unidos. Nuestros resultados muestran que una minoría significativa de inmigrantes dominicanos asegura haber sido tratada injustamente, principalmente debido a su "raza y etnicidad". Además, sus experiencias con algunos tipos de discriminación están positivamente asociadas con el color de la piel (o sea, piel oscura) y varios factores identificados en la literatura sobre modelos de asimilación. [source] Immigrant Gateways and Hispanic Migration to New Destinations,INTERNATIONAL MIGRATION REVIEW, Issue 3 2009Daniel T. Lichter Our understanding of the underlying demographic components of population change in new Hispanic destinations is limited. In this paper, we (1) compare Hispanic migration patterns in traditional settlement areas with new growth in emerging Hispanic destinations; (2) examine the role of immigration vis-à-vis domestic migration in spurring Hispanic population redistribution; and (3) document patterns of migrant selectivity, distinguishing between in-migrants and non-migrant Hispanics at both the origin and destination. We use several recent datasets, including the 1990 and 2000 Public Use Microdata Samples (which include new regional geocodes), and the 2005 and 2006 files of the American Community Survey. Our results document the widespread dispersion of the Hispanic population over the 1990,2006 period from established Hispanic gateways into new Hispanic areas and other parts of the country. Nearly one-half of Hispanic net migration in new destinations comes from domestic gains. In contrast, both established and other Hispanic areas depend entirely on immigration, with each losing domestic migrants to high growth areas. Migrant flows also are highly differentiated by education, citizenship, and nativity. To fully understand the spatial diffusion of Hispanics requires a new appreciation of the complex interplay among immigration, internal domestic migration, and fertility. [source] The 21st-Century American Geriatrics Society: Destinations and Highways to Get ThereJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2007David B. Reuben MD No abstract is available for this article. [source] Tracking Post-school Destinations of Young People with Mild Intellectual Disabilities: The Problem of AttritionJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 2 2006Sue Caton Background, This research was carried out as an assessment of the transition towards adult life for school leavers with mild intellectual disabilities. Ninety young people who were enrolled at three schools for people with mild intellectual disabilities were followed up for the first 12,18 months after they left school to assess how they experienced this transition. Methods, Young people were interviewed using semi-structured interviews before they left school regarding their aspirations for school leaving. They were then followed up and those who were traced were interviewed a second time regarding how they had experienced the previous year. Results, There were a number of difficulties encountered in following up the school leavers. Most importantly, there were a high number of participants who were unable to be traced for the study, by the schools, the careers office, or other service providers. The attrition started early in the transition process and was largely overlooked by the schools and careers service, presenting a challenge for successful transition experiences. Discussion, The implications of the high level of attrition are discussed. In addition, the impact of a number of new initiatives are discussed. [source] Minimizing Pathogen Transmission at Primate Ecotourism Destinations: The Need for Input from Travel MedicineJOURNAL OF TRAVEL MEDICINE, Issue 4 2009Michael P. Muehlenbein PhD, MsPH First page of article [source] Real-Time OD Estimation Using Automatic Vehicle Identification and Traffic Count DataCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2002Michael P. Dixon A key input to many advanced traffic management operations strategies are origin,destination (OD) matricies. In order to examine the possibility of estimating OD matricies in real-time, two constrained OD estimators, based on generalized least squares and Kalman filtering, were developed and tested. A one-at-a-time processing method was introduced to provide an efficient organized framework for incorporating observations from multiple data sources in real-time. The estimators were tested under different conditions based on the type of prior OD information available, the type of assignment available, and the type of link volume model used. The performance of the Kalman filter estimators also was compared to that of the generalized least squares estimator to provide insight regarding their performance characteristics relative to one another for given scenarios. Automatic vehicle identification (AVI) tag counts were used so that observed and estimated OD parameters could be compared. While the approach was motivated using AVI data, the methodology can be generalized to any situation where traffic counts are available and origin volumes can be estimated reliably. The primary means by which AVI data was utilized was through the incorporation of prior observed OD information as measurements, the inclusion of a deterministic link volume component that makes use of OD data extracted from the latest time interval from which all trips have been completed, and through the use of link choice proportions estimated based on link travel time data. It was found that utilizing prior observed OD data along with link counts improves estimator accuracy relative to OD estimation based exclusively on link counts. [source] Efficient communication using message prediction for clusters of multiprocessorsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2002Ahmad Afsahi Abstract With the increasing uniprocessor and symmetric multiprocessor computational power available today, interprocessor communication has become an important factor that limits the performance of clusters of workstations/multiprocessors. Many factors including communication hardware overhead, communication software overhead, and the user environment overhead (multithreading, multiuser) affect the performance of the communication subsystems in such systems. A significant portion of the software communication overhead belongs to a number of message copying operations. Ideally, it is desirable to have a true zero-copy protocol where the message is moved directly from the send buffer in its user space to the receive buffer in the destination without any intermediate buffering. However, due to the fact that message-passing applications at the send side do not know the final receive buffer addresses, early arrival messages have to be buffered at a temporary area. In this paper, we show that there is a message reception communication locality in message-passing applications. We have utilized this communication locality and devised different message predictors at the receiver sides of communications. In essence, these message predictors can be efficiently used to drain the network and cache the incoming messages even if the corresponding receive calls have not yet been posted. The performance of these predictors, in terms of hit ratio, on some parallel applications are quite promising and suggest that prediction has the potential to eliminate most of the remaining message copies. We also show that the proposed predictors do not have sensitivity to the starting message reception call, and that they perform better than (or at least equal to) our previously proposed predictors. Copyright © 2002 John Wiley & Sons, Ltd. [source] Primary mesenchyme cell-ring pattern formation in 2D-embryos of the sea urchinDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 1 2000Hideki Katow Primary mesenchyme cell (PMC) migration during PMC-ring pattern formation was analyzed using computer-assisted time-lapse video microscopy in spread embryos (2D-embryo) of the sea urchin, Mespilia globulus, and a computer simulation. The PMC formed a near normal ring pattern in the 2D-embryos, which were shown to be an excellent model for the examination of cell behavior in vivo by time-lapse computer analysis. The average migration distance of the ventro-lateral PMC aggregate-forming cells (AFC) and that of the dorso-ventral PMC cable-forming cells (CFC) showed no significant difference. All PMC took a rather straightforward migration path to their destinations with little lag time after ingression. This in vivo cell behavior fitted well to a computer simulation with a non-diffusable chemotaxis factor in the cyber-cell migration field. This simulation suggests that PMC recognize their destination from a very early moment of cell migration from the vegetal plate, and implicates that a chemoattractive region is necessary for making the PMC migration pattern. The left- and right-lateral AFC and dorso and ventral CFC were each derived from an unequally divided one-quarter segment of the vegetal plate. This suggests that AFC and CFC have a distinctive ancestor in the vegetal plate, and the PMC are a heterogeneous population at least in terms of their destination in the PMC-ring pattern. [source] Agrifood Sector Liberalisation and the Rise of Supermarkets in Former State-controlled Economies: A Comparative OverviewDEVELOPMENT POLICY REVIEW, Issue 5 2004Thomas Reardon Former state-controlled economies (FSCEs) have become the most important destination of global retail chain investments. These economies, which spread from North Africa, across Central and Eastern Europe, to East Asia, include more than one and a half billion consumers and a large share of the world's agricultural area and poor farmers. They have undergone an often radical transformation of their agrifood system over the past decade. The take-off of supermarkets in FSCEs started seriously in the mid-late 1990s, and is now moving fast. This article compares FSCE experience in the supermarket revolution and considers its implications for policy-makers and rural development practitioners. [source] Ooplasmic segregation in the zebrafish zygote and early embryo: Pattern of ooplasmic movements and transport pathwaysDEVELOPMENTAL DYNAMICS, Issue 8 2010Ricardo Fuentes Abstract Patterns of cytoplasmic movements and organization of transport pathways were examined in live or fixed zygotes and early zebrafish embryos using a variety of techniques. The zygote blastodisc grows by accumulation of ooplasm, transported to the animal pole from distinct sectors of ecto- and endoplasm at different speeds and developmental periods, using specific pathways or streamers. Slow transport (5 ,m/min) occurs during the first interphase along short streamers, whereas fast transport (9.6,40 ,m/min) takes place during the first cleavage division along axial and meridional streamers. Interconnections between streamers allow cargoes to change their speed and final destination. A similar sequence of events occurs during the following divisions. A complex network of microtubules and actin filaments in the endo- and ectoplasm appears to be involved in the transport of inclusions and mRNAs. Actin-dependent intermittent pulsations provoked high-speed back-and-forth movements of cytoplasm that may contribute to redistribution of organelles and maternal determinants. Developmental Dynamics 239:2172,2189, 2010. © 2010 Wiley-Liss, Inc. [source] Plasticity of the visual system after early brain damageDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2010ANDREA GUZZETTA The aim of this review is to discuss the existing evidence supporting different processes of visual brain plasticity after early damage, as opposed to damage that occurs during adulthood. There is initial evidence that some of the neuroplastic mechanisms adopted by the brain after early damage to the visual system are unavailable at a later stage. These are, for example, the ability to differentiate functional tissue within a larger dysplastic cortex during its formation, or to develop new thalamo-cortical connections able to bypass the lesion and reach their cortical destination in the occipital cortex. The young brain also uses the same mechanisms available at later stages of development but in a more efficient way. For example, in people with visual field defects of central origin, the anatomical expansion of the extrastriatal visual network is greater after an early lesion than after a later one, which results in more efficient mechanisms of visual exploration of the blind field. A similar mechanism is likely to support some of the differences found in people with blindsight, the phenomenon of unconscious visual perception in the blind field. In particular, compared with people with late lesions, those with early brain damage appear to have stronger subjective awareness of stimuli hitting the blind visual field, reported as a conscious feeling that something is present in the visual field. Expanding our knowledge of these mechanisms could help the development of early therapeutic interventions aimed at supporting and enhancing visual reorganization at a time of greatest potential brain plasticity. [source] Cerebellar granule cells show age-dependent migratory differences in vitroDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2005Krisztián Tárnok Abstract Developmental differences between cerebellar granule cells during their migratory period were revealed using dissociated granule cell cultures isolated from 4, 7, or 10 days old (P4, P7, P10) mice. Under all culture conditions, the great majority of cultivated cell populations consisted of those granule cells that had not reach their final destination in the internal granule cell layer (IGL) by the age of isolation. In vitro morphological development and the expression of migratory markers (TAG-1, astrotactin, or EphB2) showed similar characteristics between the cultures. The migration of 1008 granule cells isolated from P4, P7, and P10 cerebella and cultivated under identical conditions were analyzed using statistical methods. In vitro time-lapse videomicroscopy revealed that P4 cells possessed the fastest migratory speed while P10 granule cells retained their migratory activity for the longest time in culture. Cultures obtained from younger postnatal ages showed more random migratory trajectories than P10 cultures. Our observations indicate that despite similar morphological and molecular properties, migratory differences exist in granule cell cultures isolated from different postnatal ages. Therefore, the age of investigation can substantially influence experimental results on the regulation of cell migration. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 [source] Adaptive advantages of myrmecochory: the predator-avoidance hypothesis tested over a wide geographic rangeECOGRAPHY, Issue 5 2005Antonio J. Manzaneda The predator-avoidance hypothesis states that once released from the parent plant, myrmecochorous seeds are rapidly taken by ants to their nests, where they are protected from predators. Previous studies conducted to test this hypothesis have frequently neglected two major aspects necessary for its verification: 1) the influence of processes acting after the seed release and 2) the spatial evenness of such processes. Thus, large-scale variations in the mechanisms acting beyond seed release, and possibly influencing seed escape from predators, remain poorly documented. Here, we present the results of a post-dispersal seed-removal experiment on the myrmecochorous herb Helleborus foetidus, aimed at verifing the predator-avoidance hypothesis by considering two key post-release aspects of seed fate: seed destination (dispersed or nondispersed) and seed burial (buried or not buried). Experiments were performed in four different regions in the Iberian Peninsula. After three days of exposure of seeds to the main predator (fieldmice Apodemus sylvaticus), ca 30% of the seeds were removed. Seed destination affected the proportion of seeds escaping predation, but the sign, magnitude and statistical significance of the effect varied among the geographical regions. In the southern region (Cazorla), seeds dispersed in ant nests or intermediate destinations suffered scarcely any predation, but seeds under reproductive-age plants experienced losses ca 50%. Conversely, in the northern region (Caurel), seeds in nests suffered significantly greater losses than seeds under plants or intermediate destinations, suggesting that nests were especially unsafe destinations. Seed burial had a strong impact on seed escape from predators, and its effect was highly consistent among geographical regions. In view of the consistency of its effect at different spatial scales, seed burial was a more general mechanism for predation avoidance than seed relocation to ant nests, which was habitat- and/or ant-species-dependent. Our results thus only partially support the predator-avoidance hypothesis for the evolution of myrmecochory. [source] Effect of habitat fragmentation on spawning migration of brown trout (Salmo trutta L.)ECOLOGY OF FRESHWATER FISH, Issue 3 2006C. Gosset Abstract , Human-induced habitat alteration is one of the main causes of the decline of freshwater fish populations. The watershed of the River Bidasoa (Spain) is an example of heavily fragmented habitat. The local brown trout (Salmo trutta L.) population is disturbed, with evidence of poor recruitment as well as low adult densities in the main stem. Forty male and female adult migratory trout were tagged with external or internal radio transmitters and released. Fixed stations with data loggers and mobile antennae were used with daily surveys to track fish movements during the migration and spawning period (3 months). Migration distances did not exceed 10 km, and half of the fish never entered a tributary in the study area. Fragmentation because of weirs on the main stem apparently prevented fish from reaching their spawning destination. Fish that entered the tributaries were first confronted with an accessibility problem because of low discharge. However, each fish chose one tributary, without making attempts to run up in other tributaries. Once in the tributary, fish were restrained in their upstream movements by dams. The study area appeared to be isolated from the vast upper part of the watershed. Within the study area, upper parts of tributaries also seemed strongly disconnected from the main stem. This study illustrates the negative impact of river fragmentation on S. trutta migration pattern. Population sustainability can be directly affected through the low availability of spawning grounds for migratory fish. Long-term effects of fragmentation may cause reproductive isolation within watersheds, which in the case of trout also means isolated phenotypic population units. [source] MIGRATION, GLOBALISATION AND THE SPIRIT OF PETER BAUERECONOMIC AFFAIRS, Issue 4 2003Daniel T. Griswold Lord Bauer understood that the human freedom of movement plays a vital role in development. Today, internal and cross-border migration generates hard-currency remittances that raise living standards and capital investment in the country of origin, promotes greater trade and investment ties between destination and origin countries, and raises a country's stock of human and physical capital when migrants return with new skills and investment funds. Immigration can also stimulate political and social reform when migrants return or foreign-born immigrants arrive with new ideas and experiences. Relaxing the pervasive controls on the international movement of people remains a huge piece of unfinished business on the market-driven development agenda. [source] Investigating moderate to severe paediatric trauma in the Auckland regionEMERGENCY MEDICINE AUSTRALASIA, Issue 2 2010Louise Couch Abstract Objective: To investigate differences between paediatric patients with moderate to severe trauma admitted from two paediatric ED, with respect to: demographics, patterns of presentation, mechanism of injury, injury severity scores (ISS), interventions and outcome. Method: Retrospective cohort study. Moderate to severe trauma was defined as ISS >9. Paediatric patients admitted to hospital via Starship Children's Emergency or KidzFirst ED, with trauma from 1 May 2003 to 30 April 2004, with ISS >9 were identified using multiple databases. The charts were reviewed and data collected included: demographics, hospital of first presentation, diagnoses, ISS, Paediatric trauma score (PTS), Glasgow coma score (GCS), ventilator hours, length of admission, survival and discharge destination. Descriptive statistics with 95% confidence intervals, Mann,Whitney U -test, ,2 -test and Fisher's exact test were used as appropriate. Results: A total of 393 children with moderate to severe trauma were identified using initial search strategies. Of these, 82 children met the inclusion and exclusion criteria for the study; 42 children were admitted via KidzFirst ED and 40 via Starship Children's ED. There was no statistically significant difference in ISS (P= 0.86), PTS (P= 0.11), GCS (P= 0.62), hours on a ventilator (P= 0.28) and length of stay (P= 0.87) between children admitted from Starship or KidzFirst ED. Conclusion: This study suggests that there are no differences in the numbers or severity of paediatric trauma patients admitted from the Starship and KidzFirst ED. This indicates triage is to the closest ED despite having a tertiary referral centre for paediatric trauma available in Auckland City. [source] Dynamic zone topology routing protocol for MANETsEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 4 2007Mehran Abolhasan The limited scalability of the proactive and reactive routing protocols have resulted in the introduction of new generation of routing in mobile ad hoc networks, called hybrid routing. These protocols aim to extend the scalability of such networks beyond several hundred to thousand of nodes by defining a virtual infrastructure in the network. However, many of the hybrid routing protocols proposed to date are designed to function using a common pre-programmed static zone map. Other hybrid protocols reduce flooding by grouping nodes into clusters, governed by a cluster-head, which may create performance bottlenecks or a single point of failures at each cluster-head node. We propose a new routing strategy in which zones are created dynamically, using a dynamic zone creation algorithm. Therefore, nodes are not restricted to a specific region. Additionally, nodes perform routing and data forwarding in a cooperative manner, which means that in the case failure, route recalculation is minimised. Routing overheads are also further reduced by introducing a number of GPS-based location tracking mechanisms, which reduces the route discovery area and the number of nodes queried to find the required destination. Copyright © 2006 AEIT [source] SUBURBANIZATION IN COUNTRIES IN TRANSITION: DESTINATIONS OF SUBURBANIZERS IN THE TALLINN METROPOLITAN AREAGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 2 2007Kadri Leetmaa ABSTRACT. Suburbanization is one of the key phenomena of spatial population change in many countries in transition. Yet we know surprisingly little about the population carrying out the post-socialist suburbanization process. The objective of this article is to improve on this situation by studying the Tallinn metropolis in Estonia. Our analysis, which covers the inter-censal period 1989 to 2000, focuses on the differences between population subgroups with respect to their probabilities to move to the suburbs. As such, it also clarifies choices of destination by dwelling and municipality type. For the analysis, we use individual anonymous 2000 census data and logistic regression. The results indicate that suburbanization was a socially polarizing process during this period. People with low social status had the highest probability to sub-urbanize, and mainly occupied the pre-existing housing stock. Conversely, people with high social status were less likely to move into suburban areas, yet when they did they moved to the most attractive destinations in the suburbs (new single-family houses, coastal municipalities and municipalities closer to the city). [source] Public Education Financing Trends and the Gray Peril HypothesisGROWTH AND CHANGE, Issue 4 2009DAYTON M. LAMBERT ABSTRACT The effects of migrating seniors on the provision of local public services in rural communities is growing in importance because of the large number of retiring baby boomers and the increasing rate at which these retirees are locating outside traditional retirement destinations. Some communities are optimistic about attracting and retaining retirees as an economic development strategy, but others are concerned that inmigrating seniors may be reluctant to support local public services, such as education, bringing with them "Gray Peril." This article attempts to clarify questions regarding the Gray Peril hypothesis and local ability and willingness to fund education in Tennessee, an increasingly popular retirement destination. To this end, county per pupil education expenditure growth is explained by growth trends in local property tax assessment and sales tax revenue, and migration patterns of the retirement-aged population from 1962 to 2002. [source] Body condition, growth rates and diet of Skylark Alauda arvensis nestlings on lowland farmlandIBIS, Issue 3 2001PAUL F. DONALD Factors affecting the diet, body condition and growth rates of Skylark chicks were assessed to examine their relationship to their agricultural environment during a critical period in the life cycle of this rapidly declining species. Rainfall explained the greatest amount of variation in body condition and growth rates and had a negative effect on both. Body condition indices were a good predictor of the likelihood of future partial brood loss to starvation. Low body condition in grass fields was related to a low diversity in the diet. Chicks fed insect larvae had higher body condition indices than those not fed larvae. Larger broods tended to have higher growth rates than smaller ones, whereas smaller broods tended to have higher body condition indices. Natural brood size reduction through the non-hatching of eggs resulted in higher body condition indices than were found in nests with the same number of chicks where all eggs hatched, this effect being independent of absolute brood size. There was no significant difference between crop types in the distance adult birds flew to forage for food for nestlings and foraging crop destination had no effect on chick development. Differences between crop types in chick diet could be related to the documented effects of pesticides on different prey species. We suggest that recent agricultural changes have affected diet and possibly body condition, but that these effects are unlikely to have been an important factor in recent population declines. [source] Home Bias in Leveraged Buyouts,INTERNATIONAL FINANCE, Issue 3 2009Peter Cornelius In this paper, we examine cross-border investments in 2,260 portfolio companies by 102 buyout funds raised between 1995 and 2004. Using proprietary data compiled by AlpInvest Partners, we calculate the aggregate home bias of these funds as well as their home bias at the fund level. We find significant variation across funds. While UK-based funds are on average least home-biased, they show a high degree of intra-European bias. In comparison, US funds are found to be least home-biased in terms of inter-regional acquisitions, with Europe being the most important destination for US buyout capital. Furthermore, we find that buyout funds tend to be less home-biased than portfolio investors and, more specifically, mutual funds. This finding is consistent with the optimal ownership theory of the home bias, which predicts that foreign direct investment , as opposed to portfolio investment , represents the preferred choice of entry in countries where the quality of governance is perceived to be inferior, promoting insider ownership. [source] Design and evaluation of inter-bandwidth broker signalingINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 8 2008Haci A. Mantar Abstract Bandwidth brokers (BBs) have been proposed for providing end-to-end quality of services (QoS) in differentiated services (Diffserv) networks. As a single entity in each domain, a BB aims at performing both intra- and inter-domain resource management on behalf of its domain. There have been plenty of BB studies for intra-domain resource management. However, how a BB can perform inter-domain resource management in a scalable and deployable manner is still an open issue. In this work, we present the design, implementation and evaluation of an inter-BB communication protocol that is used by each BB to communicate with its neighboring BBs for inter-domain QoS resource management. The proposed model uses a destination-based aggregation scheme in which reservations are aggregated as they merge through the destination region. The destination-based aggregation improves inter-domain state and signaling scalability. The protocol also performs traffic engineering to increase inter-domain resource utilization. The implementation and simulation results verify the achievements of our model. Copyright © 2008 John Wiley & Sons, Ltd. [source] On the application of forking nodes to product-form queueing networks,INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 2 2008Essia H. Elhafsi Abstract We define a ,forking node' as a service centre with one input feeding two outputs (each served by its own queue) under the control of an internal path-selection (PS) policy. We assume that both outputs lead to paths through which a packet reaches its final destination. However, the mean downstream delays on the two paths may be different and the PS policy should favour the path with the lower downstream delay. Using simulation, we compare the performance of this system under a variety of random, deterministic, state-dependent PS policies, including threshold-based and join-shortest-queue with bias (JSQ + b). We show that JSQ + b has better performance than the other alternatives. Moreover, if the input process to the forking node is Poisson, standard time series analysis techniques show that its two outputs are very close to being independent Poisson processes. Thus, if we find an accurate and efficient ,offline' analytical performance model for JSQ + b forking node, we can extend the applicability of product-form queueing networks to include such forking nodes. For this reason, we present several ways of modelling the performance of a JSQ + b node, using bounds, and compare their results on example networks. We establish a closed-form expression relating the bias b and the delays of the downstream paths. Copyright © 2007 John Wiley & Sons, Ltd. [source] Clock synchronization for packet networks using a weighted least-squares error filtering technique and enabling circuit emulation serviceINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 6 2007James Aweya Abstract Circuit emulation service (CES) allows time-division multiplexing (TDM) services (T1/E1 and T3/E3 circuits) to be transparently extended across a packet network. With circuit emulation over IP, for instance, TDM data received from an external device at the edge of an IP network is converted to IP packets, sent through the IP network, passed out of the IP network to its destination, and reassembled into TDM bit stream. Clock synchronization is very important for CES. This paper presents a clock synchronization scheme based on a double exponential filtering technique and a linear process model. The linear process model is used to describe the behaviour of clock synchronization errors between a transmitter and a receiver. In the clock synchronization scheme, the transmitter periodically sends explicit time indications or timestamps to a receiver to enable the receiver to synchronize its local clock to the transmitter's clock. A phase-locked loop (PLL) at the receiver processes the transmitted timestamps to generate timing signal for the receiver. The PLL has a simple implementation and provides both fast responsiveness (i.e. fast acquisition of transmitter frequency at a receiver) and significant jitter reduction in the locked state. Copyright © 2006 John Wiley & Sons, Ltd. [source] Priority-based adaptive routing in NGEO satellite networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 3 2007Ömer Korçak Abstract In a non-geostationary satellite constellation with inter satellite links (ISLs), there could be many shortest paths between two satellites in terms of hop count. An efficient routing algorithm should effectively use these paths in order to distribute traffic to ISLs in a balanced way and to improve the performance of the system. This paper presents and evaluates a novel priority-based adaptive shortest path routing (PAR) scheme in order to achieve this goal. PAR sets the path towards the destination in a distributed manner, using a priority mechanism depending on the past utilization and buffering information of the ISLs. Moreover, to avoid unnecessary splitting of a flow and to achieve better utilization of ISLs, enhanced PAR (ePAR) scheme is proposed. This paper evaluates performance of the proposed techniques by employing an extensive set of simulations. Furthermore, since there are a number of ePAR parameters that should be adjusted depending on the network and traffic characteristics, a detailed analysis of ePAR scheme is provided to form a framework for setting the parameters. This paper also includes a method for adaptation of the proposed algorithms to minimum-delay path routing. Copyright © 2006 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||