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21.
Somsak Vanit-Anunchai Jonathan Billington Guy Edward Gallasch 《International Journal on Software Tools for Technology Transfer (STTT)》2008,10(1):29-56
State space explosion is a key problem in the analysis of finite state systems. The sweep-line method is a state exploration
method which uses a notion of progress to allow states to be deleted from memory when they are no longer required. This reduces
the peak number of states that need to be stored, while still exploring the full state space. The technique shows promise
but has never achieved reductions greater than about a factor of 10 in the number of states stored in memory for industrially
relevant examples. This paper discusses sweep-line analysis of the connection management procedures of a new Internet standard,
the Datagram Congestion Control Protocol (DCCP). As the intuitive approaches to sweep-line analysis are not effective, we
introduce new variables to track progress. This creates further state explosion. However, when used with the sweep-line, the
peak number of states is reduced by over two orders of magnitude compared with the original. Importantly, this allows DCCP
to be analysed for larger parameter values.
Somsak Vanit-Anunchai was partially supported by an Australian Research Council Discovery Grant (DP0559927) and Suranaree
University of Technology.
Guy Edward Gallasch was supported by an Australian Research Council Discovery Grant (DP0559927). 相似文献
22.
Edward C. Malthouse 《Data mining and knowledge discovery》2007,15(3):383-402
This paper discusses a new application of data mining, quantifying the importance of responding to trigger events with reactive
contacts. Trigger events happen during a customer’s lifecycle and indicate some change in the relationship with the company.
If detected early, the company can respond to the problem and retain the customer; otherwise the customer may switch to another
company. It is usually easy to identify many potential trigger events. What is needed is a way of prioritizing which events
demand interventions. We conceptualize the trigger event problem and show how survival analysis can be used to quantify the
importance of addressing various trigger events. The method is illustrated on four real data sets from different industries
and countries. 相似文献
23.
Sood Johanna R.; Cisek Edward; Zimmerman Joan; Zaleski Ellen H.; Fillmore Herbert H. 《Canadian Metallurgical Quarterly》2003,48(1):44
Objective: To replicate and extend P. A. Lichtenberg and colleagues' (1996) cross-disciplinary intervention to improve physical and mental health among older adults. Participants: 14 depressed older adults (6 treatment, 8 control). Setting: The short-term rehabilitation unit of an urban nursing home. Intervention: Occupational therapists were trained to treat depression using pleasant events and cognitive-behavioral therapies. Outcome Measures: Geriatric Depression Scale, the Short Form-12, and the Multi-Level Assessment Instrument: Activities of Daily Living. Results: No significant group differences were found in physical or mental health. However, more control group members (75%) than treatment group members (33%) were depressed at study completion. Conclusions: The treatment of depressive symptoms can be integrated with a nonmental health treatment modality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
24.
Hydroprocessing of heavy petroleum feeds: Tutorial 总被引:1,自引:0,他引:1
25.
The accumulation of two independent, broadly applicable formulations for determining the boundary to manipulator workspaces, presented elsewhere, are compared in this paper. Insights gained from one method are used to explain behavior exhibited in the other. Results are also compared and validated. A numerical formulation based on continuation methods is used to map curves that are on the boundary of a manipulator workspace. Analytical criteria based on row rank deficiency criteria of the manipulator's analytical Jacobian are used to map a family of one-dimensional solution curves on the boundary. The other formulation, based on a similar rank-deficiency criteria, yields analytic boundaries parametrized in terms of surface patches on the boundary. Results concerning the applicability of the numerical method to open- and closed-loop systems are compared with those limited to the open-loop for the analytical method. Conclusions regarding the behavior of the manipulator on geometric entities characterized by singular curves, higher-order bifurcation points, and surfaces inside the workspace are drawn. Applicability of both methods and their limitations are also addressed. 相似文献
26.
SA Morse DL Trees Y Htun F Radebe KA Orle Y Dangor CM Beck-Sague S Schmid G Fehler JB Weiss RC Ballard 《Canadian Metallurgical Quarterly》1997,175(3):583-589
A multiplex polymerase chain reaction (M-PCR) assay for Haemophilus ducreyi, Treponema pallidum, and herpes simplex virus (HSV) was compared with clinical and standard laboratory methods for the diagnosis of genital ulcer disease (GUD) in 105 patients; 36% were human immunodeficiency virus (HIV)-seropositive. Chancroid (80%), syphilis (8%), and genital herpes (8%) were the most frequent diagnoses. H. ducreyi and HSV were isolated from ulcers of 43% and 18% of patients, respectively; in 35%, all cultures were negative and the laboratory diagnosis indeterminate. M-PCR detected H. ducreyi, T. pallidum, and HSV in 56%, 23%, and 26% of patients, respectively; (no definitive diagnosis, 6%). The proportion of patients with more than one agent was 4% by culture and 17% by M-PCR (P = .002). Resolved sensitivities of M-PCR for H. ducreyi and HSV cultures were 95% and 93%, respectively. The sensitivities of H. ducreyi and HSV cultures were 75% and 60%, respectively. HSV, detected in 47% of specimens from HIV-infected versus 16% from HIV-uninfected patients (P < .001), may be emerging as a more frequent cause of GUD. 相似文献
27.
Myers Jerome L.; O'Brien Edward J.; Albrecht Jason E.; Mason Robert A. 《Canadian Metallurgical Quarterly》1994,20(4):876
Previous research demonstrated a contradiction effect: Although text currently being processed was locally coherent, readers were aware of inconsistencies between a protagonist's actions and characteristics of the protagonists that were described earlier in the text and subsequently backgrounded. In the present experiments, not only the critical characteristics but also the protagonist were backgrounded. When the protagonist was reintroduced into the narrative in the context of carrying out an inconsistent action, the contradiction effect again occurred. In Exps 1–3, we examined the effects of several variables on the onset of the effect. In Exp 4, we presented probes at various points in the passage with results that supported the conclusion that the critical characteristics had been backgrounded before the sentence that contradicted them. Results are discussed in terms of several recent models in which currently active representational elements serve as retrieval cues for other inactive, but highly related, elements. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
29.
A national survey of school psychologists' acceptability of psychological assessment techniques in the area of externalizing problem behaviors was examined. School psychologists' ratings of 2 procedures, Behavioral Assessment (BA) and Traditional Assessment (TA), were compared using an analog case study methodology. Using a random sample of 500 National Association of School Psychologists members from the 1991–1992 membership directory, 339 Ss completed the Assessment Rating Profile after reading a hypothetical case summary describing a student with suspected externalizing problem behaviors. Results indicated statistically significant differences between assessment methods and ratings of acceptability. BA procedures were found to be more acceptable than TA procedures. Implications related to the acceptability of psychological assessment techniques, as well as implications for school psychology practitioners are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Yuansheng Jiang Yihan Shao Edward C. Kirby 《Fullerenes, Nanotubes and Carbon Nanostructures》1994,2(4):481-497
An algorithm to generate the molecular graphs of the trivalent clusters is presented. All the polyhedral trivalent cages with 4-16 vertices are enumerated, with particular attention being given to their symmetry, spectra and stability. The relative stability of isomers is not decided solely by their symmetry. A new kind of spectral phenomenon is reported. This is the occurrence of graphs having the same HOMO-LUMO gap, the same E and the same even-order moments. We refer to it as 'pseudo-isospectrality'. 相似文献