14,241 research outputs found
The relationships between corruption and pollution on corruption regimes
Previous studies have focused mainly on the effect of corruption on pollution. The results of these studies show an inverted U-shaped relationship between economic growth and pollution. In addition, some researchers have suggested that corruption plays an important role in determining pollution. This study proposes the hypothesis of a nonlinear long-run relationship between pollution and corruption. The goal of the study is to investigate the threshold cointegration effect of pollution on corruption using panel data for 62 countries over the period from 1997 to 2004. The results show that the effect of the Corruption Perceptions Index (CPI) on pollution is insignificant in low-corruption regimes. This implies that corruption does not slow down environmental pollution in countries with low corruption. The impact of the CPI on environmental pollution is also insignificant in high-corruption regimes. This result implies that corruption has no adverse impact on environmental pollution in countries with high corruption.Corruption, Pollution, Threshold, Error-Correction Model
Heterogeneity-aware scheduling and data partitioning for system performance acceleration
Over the past decade, heterogeneous processors and accelerators have become increasingly prevalent in modern computing systems. Compared with previous homogeneous parallel machines, the hardware heterogeneity in modern systems provides new opportunities and challenges for performance acceleration. Classic operating systems optimisation problems such as task scheduling, and application-specific optimisation techniques such as the adaptive data partitioning of parallel algorithms, are both required to work together to address hardware heterogeneity.
Significant effort has been invested in this problem, but either focuses on a specific type of heterogeneous systems or algorithm, or a high-level framework without insight into the difference in heterogeneity between different types of system. A general software framework is required, which can not only be adapted to multiple types of systems and workloads, but is also equipped with the techniques to address a variety of hardware heterogeneity.
This thesis presents approaches to design general heterogeneity-aware software frameworks for system performance acceleration. It covers a wide variety of systems, including an OS scheduler targeting on-chip asymmetric multi-core processors (AMPs) on mobile devices, a hierarchical many-core supercomputer and multi-FPGA systems for high performance computing (HPC) centers. Considering heterogeneity from on-chip AMPs, such as thread criticality, core sensitivity, and relative fairness, it suggests a collaborative based approach to co-design the task selector and core allocator on OS scheduler. Considering the typical sources of heterogeneity in HPC systems, such as the memory hierarchy, bandwidth limitations and asymmetric physical connection, it proposes an application-specific automatic data partitioning method for a modern supercomputer, and a topological-ranking heuristic based schedule for a multi-FPGA based reconfigurable cluster.
Experiments on both a full system simulator (GEM5) and real systems (Sunway Taihulight Supercomputer and Xilinx Multi-FPGA based clusters) demonstrate the significant advantages of the suggested approaches compared against the state-of-the-art on variety of workloads."This work is supported by St Leonards 7th Century Scholarship and
Computer Science PhD funding from University of St Andrews; by UK
EPSRC grant Discovery: Pattern Discovery and Program Shaping for Manycore
Systems (EP/P020631/1)." -- Acknowledgement
The impact of negative events in scenic spots on tourists' behavioral intention: an analysis from the perspective of event system theory
Tourism is an important economic activity in China representing about 11.04% of GDP
and 10.29% of total employment. In recent years, negative events occurred frequently in
Chinese tourism spots, especially in scenic spots, and tended to be promptly divulgated through
social networks. The impact of these fast-running news on tourism activity is still to be
appraised. This study reviews the literature on negative events, and e-word-of-mouth effects,
jointly with personality characteristic theory, and consumer behavior intentions to address the
impact of negative events on tourism. The study contributes to the existent knowledge by using
the event theory system framework to explore how negative events affect touristsâ intentions
concerning visiting places where negative events took place. The results are meaningful both
theoretically and practically, showing that, on the one hand, the dimensions of space and
intensity proposed by the event theory system have a significant impact on touristsâ behavior
and, on another hand, touristsâ personality, namely risk-taking tendencies and openness, has a
significant impact on tourists' willingness to recommend. Further, the study addresses its
limitations and proposes management contributions, and future directions of research.O turismo Ă© uma atividade muito importante na China representando cerca de 11.04% do
seu PIB e 10.29% do seu emprego total. Recentemente, acontecimentos negativos tĂȘm ocorrido
com frequĂȘncia em locais turĂsticos, especialmente em locais de espetĂĄculos, e tĂȘm sido
rapidamente difundidos atravĂ©s das redes sociais. O impacto sobre a atividade turĂstica destas
notĂcias aceleradas estĂĄ ainda por avaliar. Este trabalho revĂȘ a literatura sobre acontecimentos
negativos e efeitos de difusĂŁo eletrĂłnica "boca-a-boca", em conjunto com a teoria da
personalidade e das intençÔes de consumo, para analisar o impacto de acontecimentos negativos
no turismo. O estudo contribui para a literatura existente ao usar o quadro do "event theory system"
para explorar como os acontecimentos negativos afetam as decisÔes dos turistas em visitar os
locais onde estes ocorreram. Os resultados sĂŁo significativos, quer do ponto de vista teĂłrico,
quer pråtico, demonstrando, por um lado, que as dimensÔes espaço e intensidade sugeridas pelo
"event theory system" tĂȘm impacto significativo no comportamento dos turistas e, por outro, que
a personalidade dos turistas, nomeadamente a sua tendĂȘncia para aceitar o risco e a sua abertura,
tem um impacto significativo na sua vontade de recomendar os locais afetados pelos
acontecimentos negativos. Adicionalmente, o estudo discute as suas limitaçÔes e propÔe
contribuiçÔes para o processo de gestão, bem como linhas de investigação futuras
Zero-Mode Contribution in Nucleon-Delta Transition
We investigate the transition form factors between nucleon and (1232)
particles by using a covariant quark-spectator-diquark field theory model in
(3+1) dimensions. Performing a light-front calculation in parallel with the
manifestly covariant calculation in light-front helicity basis, we examine the
light-front zero-mode contribution to the helicity components of light-front
good ("+") current matrix elements. Choosing the light-front gauge
() with circular polarization in Drell-Yan-West frame, we
find that only the helicity components and of the good current receive the zero-mode contribution. Taking
into account the zero-mode, we find the prescription independence in obtaining
the light-front solution of form factors from any three helicity matrix
elements with smeared light-front wavefunctions. The angular condition, which
guarantees the full covariance of different schemes, is recovered.Comment: 16 latex pages, 7 figures, to appear in PR
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