357,939 research outputs found
Two-Hop Routing with Traffic-Differentiation for QoS Guarantee in Wireless Sensor Networks
This paper proposes a Traffic-Differentiated Two-Hop Routing protocol for
Quality of Service (QoS) in Wireless Sensor Networks (WSNs). It targets WSN
applications having different types of data traffic with several priorities.
The protocol achieves to increase Packet Reception Ratio (PRR) and reduce
end-to-end delay while considering multi-queue priority policy, two-hop
neighborhood information, link reliability and power efficiency. The protocol
is modular and utilizes effective methods for estimating the link metrics.
Numerical results show that the proposed protocol is a feasible solution to
addresses QoS service differenti- ation for traffic with different priorities.Comment: 13 page
A philosophical context for methods to estimate origin-destination trip matrices using link counts.
This paper creates a philosophical structure for classifying methods which estimate origin-destination matrices using link counts. It is claimed that the motivation for doing so is to help real-life transport planners use matrix estimation methods effectively, especially in terms of trading-off observational data with prior subjective input (typically referred to as 'professional judgement'). The paper lists a number of applications that require such methods, differentiating between relatively simple and highly complex applications. It is argued that a sound philosophical perspective is particularly important for estimating trip matrices in the latter type of application. As a result of this argument, a classification structure is built up through using concepts of realism, subjectivity, empiricism and rationalism. Emphasis is put on the fact that, in typical transport planning applications, none of these concepts is useful in its extreme form. The structure is then used to make a review of methods for estimating trip matrices using link counts, covering material published over the past 30 years. The paper concludes by making recommendations, both philosophical and methodological, concerning both practical applications and further research
A philosophical context for methods to estimate origin-destination trip matrices using link counts.
This paper creates a philosophical structure for classifying methods which estimate origin-destination matrices using link counts. It is claimed that the motivation for doing so is to help real-life transport planners use matrix estimation methods effectively, especially in terms of trading-off observational data with prior subjective input (typically referred to as 'professional judgement'). The paper lists a number of applications that require such methods, differentiating between relatively simple and highly complex applications. It is argued that a sound philosophical perspective is particularly important for estimating trip matrices in the latter type of application. As a result of this argument, a classification structure is built up through using concepts of realism, subjectivity, empiricism and rationalism. Emphasis is put on the fact that, in typical transport planning applications, none of these concepts is useful in its extreme form. The structure is then used to make a review of methods for estimating trip matrices using link counts, covering material published over the past 30 years. The paper concludes by making recommendations, both philosophical and methodological, concerning both practical applications and further research
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Demographics and financial asset prices in the major industrial economies
This paper explores the relationship between demographics and aggregate financial asset prices in 7
OECD countries over the past 50 years. Unlike most extant work it adopts an international as well as
US focus, and also includes non-demographic variables usually considered to influence asset prices in
the econometric specification. Furthermore, we examine effects on bond yields as well as share prices.
The results indicate a significant link between panel, international and US demographics on the one
hand, and real stock prices and real bond yields on the other. The international results are of particular
interest given their robustness and the logic of international financial integration. Generally, an
increase in the fraction of middle-aged people (aged 40-64) tends to boost real asset prices. A
corollary is that a decline in this cohort in coming decades will tend to weaken them. More tentative
results including estimated effects of the over-65 cohort in the US suggest a more severe downturn is
possible, thus underlining the potential market risks associated with sole reliance on fully funded
pension schemes
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Social Influence and Individual Difference in Experimental Juries
In a jury decision-making, individuals must compromise in order to reach a group consensus. If individuals compromise for non-rational reasons, such as a preference for conformity or due to erroneous information, then the final decision of the group may be biased. This paper presents original experimental data which shows that groups do have a significant tendency to compromise in jury-like settings. Econometric evidence also shows that features of groups, including the generosity of the group overall, will dictate the extent of compromise. The data also reveal that individual traits such as gender and capacity for empathy are associated with the extent of compromise in a jury-type setting. The implications are that interactions between individual and group characteristics limit the objectivity of decision-making
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Pension funding, productivity, ageing and economic growth
A key issue in pension reform is whether such a shift from PAYG to funding is largely a
matter of reallocation of the financial burden of ageing (with the risk of a generation paying twice), or
whether funding improves economic performance sufficiently to generate the resources required to
meet the needs of an ageing population. This paper surveys the literature on the three main aspects of
this question, whether pension funding boosts saving, whether it improves the supply of long term
funds and whether there are improvements in allocative efficiency in capital and labour markets. It
also provides new evidence on the positive benefits of funding for productivity growth, which can
offset the deleterious effects on productivity that ageing may hav
Psychometric Evaluation of the Physical Activity Enjoyment Scale in Adults with Functional Limitations
Enjoyment is an important construct for understanding physical activity participation, and it has not been examined in adults with functional limitations. This secondary analysis reported the reliability and validity of the Physical Activity Enjoyment Scale (PACES) in a convenience sample of 40 adults with functional limitations. The participants completed the PACES, Center for Epidemiological Studies Depression Scale (CES-D), and the Late Life Function and Disability Instrument (LLFDI) prior to beginning a 12-week feasibility dance intervention study. Results indicated reliability as Cronbach\u27s alpha was .95 and mean inter-item correlation was .52. To further support reliability, homogeneity of the instrument was evaluated using item-to-total scale correlations. Homogeneity was supported as all items had corrected item-to-total correlations greater than .30. For validity, the PACES was significantly related to only the Physical Function component of the LLFDI (r = .38, p = .02), but not the CES-D. Exploratory factor analysis revealed a 3-factor structure that accounted for 73.76% of the variance. This feasibility intervention dance study represented the first attempt to examine the psychometric properties of the PACES in adults with functional limitations. The findings demonstrate support for the scale\u27s reliability and validity among adults with functional limitations. Results are informative as further psychometric testing of the PACES is recommended using randomized clinical trials with larger sample sizes. Enjoyment for physical activity is an important construct for understanding physical activity participation in adults with functional limitations
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Is there a link between pension-fund assets and economic growth? - A cross-country study
Debate over superiority of pension funding over pay-as-you-go links notably to the question
whether funding improves economic performance sufficiently to generate additional resources to meet
the needs of an ageing population. To address this issue, we design a modified Cobb-Douglas
production function with pension assets as a shift factor, and investigate the direct link between pension
assets and economic growth employing a dataset covering up to 38 countries, using a variety of
appropriate econometric methods. We find positive results for both OECD countries and Emerging
Market Economies (EMEs), with consistent evidence for a larger effect for EMEs than OECD
countries
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