840 resultados para RESONANTLY TRANSITIONAL LOWER LEVEL
Resumo:
Current low-level networking abstractions on modern operating systems are commonly implemented in the kernel to provide sufficient performance for general purpose applications. However, it is desirable for high performance applications to have more control over the networking subsystem to support optimizations for their specific needs. One approach is to allow networking services to be implemented at user-level. Unfortunately, this typically incurs costs due to scheduling overheads and unnecessary data copying via the kernel. In this paper, we describe a method to implement efficient application-specific network service extensions at user-level, that removes the cost of scheduling and provides protected access to lower-level system abstractions. We present a networking implementation that, with minor modifications to the Linux kernel, passes data between "sandboxed" extensions and the Ethernet device without copying or processing in the kernel. Using this mechanism, we put a customizable networking stack into a user-level sandbox and show how it can be used to efficiently process and forward data via proxies, or intermediate hosts, in the communication path of high performance data streams. Unlike other user-level networking implementations, our method makes no special hardware requirements to avoid unnecessary data copies. Results show that we achieve a substantial increase in throughput over comparable user-space methods using our networking stack implementation.
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Background: The Early Development Instrument (EDI) is a population-level measure of five developmental domains at school-entry age. The overall aim of this thesis was to explore the potential of the EDI as an indicator of early development in Ireland. Methods: A cross-sectional study was conducted in 47 primary schools in 2011 using the EDI and a linked parental questionnaire. EDI (teacher completed) scores were calculated for 1,344 children in their first year of full-time education. Those scoring in the lowest 10% of the sample population in one or more domains were deemed to be 'developmentally vulnerable'. Scores were correlated with contextual data from the parental questionnaire and with indicators of area and school-level deprivation. Rasch analysis was used to determine the validity of the EDI. Results: Over one quarter (27.5%) of all children in the study were developmentally vulnerable. Individual characteristics associated with increased risk of vulnerability were being male; under 5 years old; and having English as a second language. Adjusted for these demographics, low birth weight, poor parent/child interaction and mother’s lower level of education showed the most significant odds ratios for developmental vulnerability. Vulnerability did not follow the area-level deprivation gradient as measured by a composite index of material deprivation. Children considered by the teacher to be in need of assessment also had lower scores, which were not significantly different from those of children with a clinical diagnosis of special needs. all domains showed at least reasonable fit to the Rasch model supporting the validity of the instrument. However, there was a need for further refinement of the instrument in the Irish context. Conclusion: This thesis provides a unique snapshot of early development in Ireland. The EDI and linked parental questionnaires are promising indicators of the extent, distribution and determinants of developmental vulnerability.
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In this paper, a multi-level wordline driver scheme is presented to improve SRAM read and write stability while lowering power consumption during hold operation. The proposed circuit applies a shaped wordline voltage pulse during read mode and a boosted wordline pulse during write mode. During read, the applied shaped pulse is tuned at nominal voltage for short period of time, whereas for the remaining access time, the wordline voltage is reduced to a lower level. This pulse results in improved read noise margin without any degradation in access time which is explained by examining the dynamic and nonlinear behavior of the SRAM cell. Furthermore, during hold mode, the wordline voltage starts from a negative value and reaches zero voltage, resulting in a lower leakage current compared to conventional SRAM. Our simulations using TSMC 65nm process show that the proposed wordline driver results in 2X improvement in static read noise margin while the write margin is improved by 3X. In addition, the total leakage of the proposed SRAM is reduced by 10% while the total power is improved by 12% in the worst case scenario of a single SRAM cell. The total area penalty is 10% for a 128Kb standard SRAM array.
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A speech message played several metres from the listener in a room is usually heard to have much the same phonetic content as it does when played nearby, even though the different amounts of reflected sound make the temporal envelopes of these signals very different. To study this ‘constancy’ effect, listeners heard speech messages and speech-like sounds comprising 8 auditory-filter shaped noise-bands that had temporal envelopes corresponding to those in these filters when the speech message is played. The ‘contexts’ were “next you’ll get _to click on”, into which a “sir” or “stir” test word was inserted. These test words were from an 11-step continuum, formed by amplitude modulation. Listeners identified the test words appropriately, even in the 8-band conditions where the speech had a ‘robotic’ quality. Constancy was assessed by comparing the influence of room reflections on the test word across conditions where the context had either the same level of room reflections (i.e. from the same, far distance), or where it had a much lower level (i.e. from nearby). Constancy effects were obtained with both the natural- and the 8-band speech. Results are considered in terms of the degree of ‘matching’ between the context’s and test-word’s bands.
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This study aimed to verify the influence of the transport in open or closed compartments (0 h), followed by two resting periods (1 and 3 h) for the slaughter process on the levels of cortisol as a indicative of stress level. At the slaughterhouse, blood samples were taken from 86 lambs after the transport and before slaughter for plasma cortisol analysis. The method of transport influenced in the cortisol concentration (0 h; P < 0.01). The animals transported in the closed compartment had a lower level (28.97 ng ml(-1)) than the animals transported in the open compartment (35.49 ng ml(-1)). After the resting period in the slaughterhouse. there was a decline in the plasmatic cortisol concentration, with the animals subjected to 3 h of rest presenting the lower average cortisol value (24.14 ng ml(-1); P < 0.05) than animals subjected to 1 h of rest (29.95 ng ml(-1)). It can be inferred that the lambs that remained 3 h in standby before slaughter had more time to recover from the stress of the transportation than those that waited just 1 h. Visual access to the external environment during the transport of the lambs is a stressful factor changing the level of plasmatic cortisol, and the resting period before slaughter was effective in lowering stress, reducing the plasmatic cortisol in the lambs. (c) 2012 Elsevier B.V. All rights reserved.
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This dissertation takes a step towards providing a better understanding of post-socialist welfare state development from a theoretical as well as an empirical perspective. The overall analytical goal of this thesis has been to critically assess the development of social policies in Estonia, Latvia and Lithuania using them as illustrative examples of post-socialist welfare state development in the light of the theories, approaches and typologies that have been developed to study affluent capitalist democracies. The four studies included in this dissertation aspire to a common aim in a number of specific ways. The first study tries to place the ideal-typical welfare state models of the Baltic States within the well-known welfare state typologies. At the same time, it provides a rich overview of the main social security institutions in the three countries by comparing them with each other and with the previous structures of the Soviet period. It examines the social insurance institutions of the Baltic States (old-age pensions, unemployment insurance, short-term benefits, sickness, maternity and parental insurance and family benefits) with respect to conditions of eligibility, replacement rates, financing and contributions. The findings of this study indicate that the Latvian social security system can generally be labelled as a mix of the basic security and corporatist models. The Estonian social security system can generally also be characterised as a mix of the basic security and corporatist models, even if there are some weak elements of the targeted model in it. It appears that the institutional changes developing in the social security system of Lithuania have led to a combination of the basic security and targeted models of the welfare state. Nevertheless, as the example of the three Baltic States shows, there is diversity in how these countries solve problems within the field of social policy. In studying the social security schemes in detail, some common features were found that could be attributed to all three countries. Therefore, the critical analysis of the main social security institutions of the Baltic States in this study gave strong supporting evidence in favour of identifying the post-socialist regime type that is already gaining acceptance within comparative welfare state research. Study Two compares the system of social maintenance and insurance in the Soviet Union, which was in force in the three Baltic countries before their independence, with the currently existing social security systems. The aim of the essay is to highlight the forces that have influenced the transformation of the social policy from its former highly universal, albeit authoritarian, form, to the less universal, social insurance-based systems of present-day Estonia, Latvia and Lithuania. This study demonstrates that the welfare–economy nexus is not the only important factor in the development of social programs. The results of this analysis revealed that people's attitudes towards distributive justice and the developmental level of civil society also play an important part in shaping social policies. The shift to individualism in people’s mentality and the decline of the labour movement, or, to be more precise, the decline in trade union membership and influence, does nothing to promote the development of social rights in the Baltic countries and hinders the expansion of social policies. The legacy of the past has been another important factor in shaping social programs. It can be concluded that social policy should be studied as if embedded not only in the welfare-economy nexus, but also in the societal, historical and cultural nexus of a given society. Study Three discusses the views of the state elites on family policy within a wider theoretical setting covering family policy and social policy in a broader sense and attempts to expand this analytical framework to include other post-socialist countries. The aim of this essay is to explore the various views of the state elites in the Baltics concerning family policy and, in particular, family benefits as one of the possible explanations for the observed policy differences. The qualitative analyses indicate that the Baltic States differ significantly with regard to the motives behind their family policies. Lithuanian decision-makers seek to reduce poverty among families with children and enhance the parents’ responsibility for bringing up their children. Latvian policy-makers act so as to increase the birth rate and create equal opportunities for children from all families. Estonian policy-makers seek to create equal opportunities for all children and the desire to enhance gender equality is more visible in the case of Estonia in comparison with the other two countries. It is strongly arguable that there is a link between the underlying motives and the kinds of family benefits in a given country. This study, thus, indicates how intimately the attitudes of the state bureaucrats, policy-makers, political elite and researchers shape social policy. It confirms that family policy is a product of the prevailing ideology within a country, while the potential influence of globalisation and Europeanisation is detectable too. The final essay takes into account the opinions of welfare users and examines the performances of the institutionalised family benefits by relying on the recipients’ opinions regarding these benefits. The opinions of the populations as a whole regarding government efforts to help families are compared with those of the welfare users. Various family benefits are evaluated according to the recipients' satisfaction with those benefits as well as the contemporaneous levels of subjective satisfaction with the welfare programs related to the absolute level of expenditure on each program. The findings of this paper indicate that, in Latvia, people experience a lower level of success regarding state-run family insurance institutions, as compared to those in Lithuania and Estonia. This is deemed to be because the cash benefits for families and children in Latvia are, on average, seen as marginally influencing the overall financial situation of the families concerned. In Lithuania and Estonia, the overwhelming majority think that the family benefit systems improve the financial situation of families. It appears that recipients evaluated universal family benefits as less positive than targeted benefits. Some universal benefits negatively influenced the level of general satisfaction with the family benefits system provided in the countries being researched. This study puts forward a discussion about whether universalism is always more legitimate than targeting. In transitional economies, in which resources are highly constrained, some forms of universal benefits could turn out to be very expensive in relative terms, without being seen as useful or legitimate forms of help to families. In sum, by closely examining the different aspects of social policy, this dissertation goes beyond the over-generalisation of Eastern European welfare state development and, instead, takes a more detailed look at what is really going on in these countries through the examples of Lithuania, Latvia and Estonia. In addition, another important contribution made by this study is that it revives ‘western’ theoretical knowledge through ‘eastern’ empirical evidence and provides the opportunity to expand the theoretical framework for post-socialist societies.
Resumo:
It is a popular concept in clinical neurology that muscles of the lower face receive predominantly crossed cortico-bulbar motor input, whereas muscles of the upper face receive additional ipsilateral, uncrossed input. To test this notion, we used focal transcranial magnetic brain stimulation to quantify crossed and uncrossed cortico-muscular projections to 6 different facial muscles (right and left Mm. frontalis, nasalis, and orbicularis oris) in 36 healthy right-handed volunteers (15 men, 21 women, mean age 25 years). Uncrossed input was present in 78% to 92% of the 6 examined muscles. The mean uncrossed: crossed response amplitude ratios were 0.74/0.65 in right/left frontalis, 0.73/0.59 in nasalis, and 0.54/0.71 in orbicularis oris; ANOVA p>0.05). Judged by the sizes of motor evoked potentials, the cortical representation of the 3 muscles was similar. The amount of uncrossed projections was different between men and women, since men had stronger left-to-left projections and women stronger right-to-right projections. We conclude that the amount of uncrossed pyramidal projections is not different for muscles of the upper from those of the lower face. The clinical observation that frontal muscles are often spared in central facial palsies must, therefore, be explained differently. Moreover, gender specific lateralization phenomena may not only be present for higher level behavioural functions, but may also affect simple systems on a lower level of motor hierarchy.
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In numerous intervention studies and education field trials, random assignment to treatment occurs in clusters rather than at the level of observation. This departure of random assignment of units may be due to logistics, political feasibility, or ecological validity. Data within the same cluster or grouping are often correlated. Application of traditional regression techniques, which assume independence between observations, to clustered data produce consistent parameter estimates. However such estimators are often inefficient as compared to methods which incorporate the clustered nature of the data into the estimation procedure (Neuhaus 1993).1 Multilevel models, also known as random effects or random components models, can be used to account for the clustering of data by estimating higher level, or group, as well as lower level, or individual variation. Designing a study, in which the unit of observation is nested within higher level groupings, requires the determination of sample sizes at each level. This study investigates the design and analysis of various sampling strategies for a 3-level repeated measures design on the parameter estimates when the outcome variable of interest follows a Poisson distribution. ^ Results study suggest that second order PQL estimation produces the least biased estimates in the 3-level multilevel Poisson model followed by first order PQL and then second and first order MQL. The MQL estimates of both fixed and random parameters are generally satisfactory when the level 2 and level 3 variation is less than 0.10. However, as the higher level error variance increases, the MQL estimates become increasingly biased. If convergence of the estimation algorithm is not obtained by PQL procedure and higher level error variance is large, the estimates may be significantly biased. In this case bias correction techniques such as bootstrapping should be considered as an alternative procedure. For larger sample sizes, those structures with 20 or more units sampled at levels with normally distributed random errors produced more stable estimates with less sampling variance than structures with an increased number of level 1 units. For small sample sizes, sampling fewer units at the level with Poisson variation produces less sampling variation, however this criterion is no longer important when sample sizes are large. ^ 1Neuhaus J (1993). “Estimation efficiency and Tests of Covariate Effects with Clustered Binary Data”. Biometrics , 49, 989–996^
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Most implementations of parallel logic programming rely on complex low-level machinery which is arguably difflcult to implement and modify. We explore an alternative approach aimed at taming that complexity by raising core parts of the implementation to the source language level for the particular case of and-parallelism. Therefore, we handle a signiflcant portion of the parallel implementation mechanism at the Prolog level with the help of a comparatively small number of concurrency-related primitives which take care of lower-level tasks such as locking, thread management, stack set management, etc. The approach does not eliminate altogether modiflcations to the abstract machine, but it does greatly simplify them and it also facilitates experimenting with different alternatives. We show how this approach allows implementing both restricted and unrestricted (i.e., non fork-join) parallelism. Preliminary experiments show that the amount of performance sacriflced is reasonable, although granularity control is required in some cases. Also, we observe that the availability of unrestricted parallelism contributes to better observed speedups.
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Simplification of texts has traditionally been carried out by replacing words and structures with appropriate semantic equivalents in the learner's interlanguage, omitting whichever items prove intractable, and thereby bringing the language of the original within the scope of the learner's transitional linguistic competence. This kind of simplification focuses mainly on the formal features of language. The simplifier can, on the other hand, concentrate on making explicit the propositional content and its presentation in the original in order to bring what is communicated in the original within the scope of the learner's transitional communicative competence. In this case, simplification focuses on the communicative function of the language. Up to now, however, approaches to the problem of simplification have been mainly concerned with the first kind, using the simplifier’s intuition as to what constitutes difficulty for the learner. There appear to be few objective principles underlying this process. The main aim of this study is to investigate the effect of simplification on the communicative aspects of narrative texts, which includes the manner in which narrative units at higher levels of organisation are structured and presented and also the temporal and logical relationships between lower level structures such as sentences/clauses, with the intention of establishing an objective approach to the problem of simplification based on a set of principled procedures which could be used as a guideline in the simplification of material for foreign students at an advanced level.
Resumo:
Firms worldwide are taking major initiatives to reduce the carbon footprint of their supply chains in response to the growing governmental and consumer pressures. In real life, these supply chains face stochastic and non-stationary demand but most of the studies on inventory lot-sizing problem with emission concerns consider deterministic demand. In this paper, we study the inventory lot-sizing problem under non-stationary stochastic demand condition with emission and cycle service level constraints considering carbon cap-and-trade regulatory mechanism. Using a mixed integer linear programming model, this paper aims to investigate the effects of emission parameters, product- and system-related features on the supply chain performance through extensive computational experiments to cover general type business settings and not a specific scenario. Results show that cycle service level and demand coefficient of variation have significant impacts on total cost and emission irrespective of level of demand variability while the impact of product's demand pattern is significant only at lower level of demand variability. Finally, results also show that increasing value of carbon price reduces total cost, total emission and total inventory and the scope of emission reduction by increasing carbon price is greater at higher levels of cycle service level and demand coefficient of variation. The analysis of results helps supply chain managers to take right decision in different demand and service level situations.
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The aim of the present study was to examine the effect of the systematic use of comics as a literary-didactic method to reduce gender differences in reading literacy and reading motivation at the primary level of education. It was assumed that the use of comics would have a positive effect on pupils’ reading literacy and reading motivation, while also reducing the aforementioned differences between boys and girls. The dimensions of reading literacy and reading motivation were examined in experimental and control groups, before and after the intervention, by means of questionnaires and tests for pupils. The sample consisted of 143 pupils from second to fifth grade from two Slovenian primary schools in a rural environment, of which 73 pupils participated in the experimental group and 70 pupils represented the control group. Effects of the use of comics as a literary-didactic method were not found: using comics as a literary-didactic method did not have a statistically significant effect on pupils’ reading literacy and reading motivation. However, when the four-way structure of the research (taking into account the age and gender of the pupils) was considered, some subgroups showed a statistically significant increase in reading interest and attitude towards reading. No reduction of gender differences in reading literacy and reading motivation was found. Based on the results, guidelines for further research are established and suggestions are offered for teachers’ work. (DIPF/Orig.)
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Despite advances in gender equity, evidence suggests that the level of business ownership by males continues to be significantly higher than that offemales. Moreover, females, from an early age, have lower entrepreneurial intentions than males. This paper examines previous studies to determine the factors that have been shown to relate to lower entrepreneurial intentions in women, to identify areas where prior research has been inadequate or inconclusive, and to discuss how intentions models might be modified to better explain the lower level of female business start-ups. It was found that the lower level of intentions is related to a range of personal background and attitudinal variables, and these factors are critically examined in this review. It is suggested that future research should focus on role models, networks and life roles in order to better explain female entrepreneurial intentions.
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This study explored the prediction of psychological climate and stresses on job satisfaction in non U.S. setting. A total of 450 surveys were sent to 11 organisations in Thailand and employees were asked to fill out the survey. The first hypothesis that positive psychological climate dimensions predicted lower level of stresses among Thai employees was partially accepted. Further regression analysis tested second hypothesis that positive psychological climate dimensions and low level of stresses predict job satisfaction among Thai employees. Contrary to expectation, only stress variables predicted job satisfaction. Thai culture influence was discussed.
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A path model was developed to examine the impact of context-specific job stressors on the work outcomes of 132 customer service employees. Respondents who reported a moderate and high level of context-specific stressors report a higher level of job demand and work family conflict. Respondents who reported a higher level of job control tend to receive more work-related support and are more satisfied with their job. Surprisingly, respondents who experienced a higher level of work family conflict tend to receive less work-related support. We found that respondents who obtained more work-related support tend to report a higher level of job satisfaction. There was also a positive relationship between positive job satisfaction and a lower level of intention to quit.