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Towards effective and efficient temporal verification in grid workflow systemsChen, Jinjun, n/a January 2007 (has links)
In grid architecture, a grid workflow system is a type of high-level grid middleware
which aims to support large-scale sophisticated scientific or business processes in a
variety of complex e-science or e-business applications such as climate modelling,
disaster recovery, medical surgery, high energy physics, international stock market
modelling and so on. Such sophisticated processes often contain hundreds of
thousands of computation or data intensive activities and take a long time to
complete. In reality, they are normally time constrained. Correspondingly, temporal
constraints are enforced when they are modelled or redesigned as grid workflow
specifications at build-time. The main types of temporal constraints include upper
bound, lower bound and fixed-time. Then, temporal verification would be conducted
so that we can identify any temporal violations and handle them in time.
Conventional temporal verification research and practice have presented some
basic concepts and approaches. However, they have not paid sufficient attention to
overall temporal verification effectiveness and efficiency. In the context of grid
economy, any resources for executing grid workflows must be paid. Therefore, more
resources should be mainly used for execution of grid workflow itself rather than for
temporal verification. Poor temporal verification effectiveness or efficiency would
cause more resources diverted to temporal verification. Hence, temporal verification
effectiveness and efficiency become a prominent issue and deserve an in-depth
investigation.
This thesis systematically investigates the limitations of conventional temporal
verification in terms of temporal verification effectiveness and efficiency. The
detailed analysis of temporal verification effectiveness and efficiency is conducted
for each step of a temporal verification cycle. There are four steps in total: Step 1 -
defining temporal consistency; Step 2 - assigning temporal constraints; Step 3 -
selecting appropriate checkpoints; and Step 4 - verifying temporal constraints.
Based on the investigation and analysis, we propose some new concepts and develop
a set of innovative methods and algorithms towards more effective and efficient
temporal verification. Comparisons, quantitative evaluations and/or mathematical
proofs are also presented at each step of the temporal verification cycle. These
demonstrate that our new concepts, innovative methods and algorithms can
significantly improve overall temporal verification effectiveness and efficiency.
Specifically, in Step 1, we analyse the limitations of two temporal consistency
states which are defined by conventional verification work. After, we propose four
new states towards better temporal verification effectiveness. In Step 2, we analyse
the necessity of a number of temporal constraints in terms of temporal verification
effectiveness. Then we design a novel algorithm for assigning a series of finegrained
temporal constraints within a few user-set coarse-grained ones. In Step 3, we
discuss the problem of existing representative checkpoint selection strategies in
terms of temporal verification effectiveness and efficiency. The problem is that they
often ignore some necessary checkpoints and/or select some unnecessary ones. To
solve this problem, we develop an innovative strategy and corresponding algorithms
which only select sufficient and necessary checkpoints. In Step 4, we investigate a
phenomenon which is ignored by existing temporal verification work, i.e. temporal
dependency. Temporal dependency means temporal constraints are often dependent
on each other in terms of their verification. We analyse its impact on overall
temporal verification effectiveness and efficiency. Based on this, we develop some
novel temporal verification algorithms which can significantly improve overall
temporal verification effectiveness and efficiency. Finally, we present an extension
to our research about handling temporal verification results since these verification
results are based on our four new temporal consistency states.
The major contributions of this research are that we have provided a set of new
concepts, innovative methods and algorithms for temporal verification in grid
workflow systems. With these, we can significantly improve overall temporal
verification effectiveness and efficiency. This would eventually improve the overall
performance and usability of grid workflow systems because temporal verification
can be viewed as a service or function of grid workflow systems. Consequently, by
deploying the new concepts, innovative methods and algorithms, grid workflow
systems would be able to better support large-scale sophisticated scientific and
business processes in complex e-science and e-business applications in the context
of grid economy.
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Discovering Moving Clusters from Spatial-Temporal DatabasesLee, Chien-Ming 28 July 2007 (has links)
Owing to the advances of computer and communication technologies, clustering analysis on moving objects has attracted increasing attention in recent years. An interesting problem is to find the moving clusters composed of objects which move along for a sufficiently long period of time. However, a moving cluster inclines to break after some time because of the goal change in each individual object. In order to identify the set of moving clusters, we propose the formal definition of moving clusters with semantically clear parameters. Based on the definition, we propose delicate approaches to cluster moving objects. The proposed approaches are evaluated using data generated with and without underlying model. We validate our approaches with a through experimental evaluation and comparison.
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Tempering optimistic bias in temporal predictions: The role of psychological distance in the unpacking effectMoher, Ester 26 July 2012 (has links)
People typically underestimate the time it will take them to complete tasks, even when they are familiar with the process of executing those tasks (the “planning fallacy”; Kahneman & Tversky, 1979; Buehler, Griffin & Ross, 1994). One reason that individuals may show a chronic misprediction of task completion time hinges on an incomplete conception of the steps required for task completion. Support Theory (Tversky & Koehler, 1994) suggests that “unpacking” such steps may help to attenuate the planning fallacy. Indeed, when a task is unpacked into procedural steps, people give longer task completion time estimates, and the planning fallacy is minimized (Kruger & Evans, 2004). Construal level theory (Liberman & Trope, 1998) suggests that a lower-level construal of a task (i.e., a task construed in the near-future) may also foster less optimistic predictions, akin to the underlying mechanism of unpacking a task. It is hypothesized that the effects of unpacking on task completion time will be more pronounced for near-future tasks, because the lower-level construal of such tasks emphasizes details of component steps, making them more readily available to be “unpacked” as part of the prediction process. Conversely, for distant-future events, unpacking effects should be attenuated. Further, these distance-dependent unpacking effects should depend critically on the content of steps unpacked. These hypotheses were tested in five studies. Unpacking effects on completion time estimates are attenuated for distant- relative to near-future tasks, and that this attenuation emerges as a result of an abstract conception of the steps of the task when considered in the distant future.
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継時的比較および社会的比較が現在の自己評価に与える影響についてNAMIKAWA, Tsutomu, 並川, 努 30 December 2009 (has links)
No description available.
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Cross-temporal relationsJohnson, Tristan Shawn 21 February 2011 (has links)
In this paper I argue that the presentist cannot deal adequately with cross-temporal relations. I look at several attempts to solve the cross-temporal relations objection and find only one that might work. Still I argue that even it can't deal with cross-temporal spatial relations such as continuity. I defend Sider here against two plausible responses. The first is that instantaneous velocities can be employed on the presentist's behalf to get them out of trouble. I argue that this response won't work. The second is a response by Dean Zimmerman in which the presentist accepts that past space-time points exist at present. I argue that his response does indeed provide us with a solution but that the cost of that solution is far too high. / text
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On checking the temporal consistency of data湯志輝, Tong, Chi-fai. January 1993 (has links)
published_or_final_version / Computer Science / Master / Master of Philosophy
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Les monoreferentiels temporels en Français moderne, writing in FrenchRalalaharimanitra, Simone 05 1900 (has links)
Temporal monoreferentials in French (hier, aujourd'hui, demain, the names of
the days and the names of the months), although used frequently, were never the
subject of a comprehensive study before Curat (1999), resulting in imprecision and
inconsistency in their classification. Defining their status is thus at the centre of this
study, which shows that hier, aujourd'hui, demain and the names of the days are
substantives, but unlike other substantives, they can, in themselves, refer to a «sole
individual* and play the role of noun phrases without a determiner. Their usage without
a determiner depends on their link to the nexus ego-hic-nunc (they are defined by the
time of their enunciation) and the unicity of their referent. They do, however, require
the presence of a determiner once detached from that nexus or when they refer to
several referents (real or not). A more or less strong lexical predisposition for
«nynegocentric» (i.e speaker referential) deicticity allows their lexeme to have a special
link with the nexus ego-hic-nunc, and the nexus thus imposes the monoreferential
constraint - hence the use without a determiner. In first place on the scale of
nynegocentric deicticity are the terms which make up the enunciative framework (je,
tu, ici, etc.). Hier, aujourd'hui and demain are placed second: they but rarely accept
the presence of a determiner. Next are the names of the days, which may be used
with or without a determiner, followed by the other substantives which require the
presence of a determiner for reference purposes. One can thus conclude that hier,
aujourd'hui, demain and the names of the days make up a subcategory of common
nouns.
The operation of the names of the months differs from that of the names of the
days in terms of both syntax and reference (they seldom vary in number, refer to one individual, and function without a determiner most of the time, independently of any
link with the nexus ego-hic-nunc); it more closely reflects that of proper nouns. They
form a subcategory of proper nouns.
The approach used, based primarily on the work of Kleiber and Curat,
was grammatical, semantic and deictic.
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Effect of long term amygdala kindling on defensive behaviour in rats : a model of the interictal emotionality associated with temporal lobe epilepsyKalynchuk, Lisa Emily 05 1900 (has links)
Temporal lobe epileptics often experience interictal (i.e., between-seizure) emotional
disturbances such as fear and anxiety. Despite the problem that these disturbances present,
little progress has been made in characterizing their nature and etiology because they are not
amenable to experimental analysis in clinical populations. Accordingly, the general purpose
of the experiments in this thesis was to demonstrate the potential of long-term amygdala
kindling in rats as a model of the interictal hyperemotionality of temporal lobe epileptics.
Seven experiments comprise this thesis. Experiments 1 and 2 established that longterm
amygdala kindling (i.e., 100 stimulations) results in large and reliable increases in
emotionality. In Experiment 1, the long-term amygdala-kindled rats displayed more
resistance to capture from an open field and more open-arm activity on an elevated plus
maze than did the sham-stimulated rats; in Experiment 2, the magnitude of this
hyperemotionality was shown to be dependent on the number of amygdala stimulations that
the rats received. Experiment 3 showed that kindling-induced hyperemotionality is
enduring; the hyperemotionality present 1 day after the final stimulation did not decline
significantly over the ensuing month although some amelioration of symptoms was
observed. Experiment 4 established that kindling-induced hyperemotionality is not unique to
amygdala stimulation. Although increases in emotionality were greatest in amygdalakindled
rats, hippocampal-kindled, but not caudate-kindled, rats also displayed significant
increases. Experiments 5 and 6 showed that kindling-induced hyperemotionality is
fundamentally defensive in nature. In Experiment 5, amygdala-kindled rats displayed high
levels of emotionality in an unfamiliar, but not in a familiar, situation; in Experiment 6,
amygdala-kindled rats displayed more defensive, but less aggressive behaviour, in their
interactions with other rats. Finally, Experiment 7 showed that 8-OH-DPAT binding to
serotonin 5HT1A receptors is increased in the dentate gyrus of amygdala-kindled rats, but
not in the amygdala, periaqueductal grey, perirhinal cortex, or CA1 or CA3 hippocampal
subfields.
Together, the results of these experiments establish the potential of long-term
amygdala kindling as a useful animal model of interictal emotionality in temporal lobe
epileptics.
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Contribution of the left and the right temporal lobes to melodic memory and perceptionSamson, Séverine January 1989 (has links)
This thesis investigated melodic memory and perception in patients with unilateral left (LT) or right (RT) temporal-lobe lesions and in normal control (NC) subjects. Experiment I examined learning and 24-hour retention of unfamiliar tunes and nonsense words. Both temporal-lobe groups were impaired in learning the tunes and the words. Long-term retention of these stimuli showed that subjects with a RT lobectomy were more impaired in recognizing the tunes than the words, while subjects with a LT lobectomy were more impaired in recognizing the words than the tunes. This study demonstrated the differenting roles of the right and the left temporal lobes in long-term retention of musical and verbal information, respectively. Experiment IIa and IIb investigated memory for songs (words sung to a tune). Recognition of the melodic component resulted in a deficit for both RT and LT groups, but the nature of the impairment seems to be related to the side of the lesion. Patients with LT lobectomy showed deficits in tune recognition mediated by words, but not for tunes sung without words. Patients with RT lobectomy were impaired in tune recognition, whether or not words were sung to the tunes. On the other hand, the well-known verbal memory deficit was shown after a LT lobectomy when the words actually form part of the stimulus as well as when the words are spoken. In experiment III two melodic discrimination tasks were created to test the hypothesis that the RT and the LT lobes are specialized for global and local information processing, respectively. The results showed that impairments under both experimental conditions regardless of the side of the temporal lobectomy suggest that the two temporal lobes are involved in the processing of contour and interval information.
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Formal specification and analysis of digital hardware circuits in LOTOSHe, Ji January 2000 (has links)
No description available.
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