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91.
Ethernet passive optical networks (EPONs) have attracted considerable attention from the industry, as they offer a simple, highly flexible and cost-effective solution to the problem of providing broadband access to a customer. The authors present a new approach to bandwidth allocation in EPONs where the optical line terminator (OLT) has full control over the access mechanism. This results in much simpler optical network unit (ONU) architecture. It is shown that such an OLT-centric architecture offers full support for differentiated services and makes enforcement of service level agreements possible. Extensive simulation experiments show that bandwidth allocation algorithms deployed in such a centralised environment can deliver good performance in terms of average and maximum packet delay. The authors introduce two new algorithms that target SLA-aware EPONs and provide a good protection of offered quality of service against interference from other sources. 相似文献
92.
Gwen van Eijk 《Journal of Housing and the Built Environment》2010,25(4):467-480
This paper examines whether and how living in a poor neighbourhood results in “network poverty”. Through a detailed analysis
of the formation of personal networks of people living in a poor neighbourhood and those living in an affluent neighbourhood
in Rotterdam, I examine the role of the neighbourhood in the formation of personal networks. I address three issues. First,
whether resource-poor people who live in a poor neighbourhood form relationships with fellow-residents to compensate for their
otherwise small network. I find that they do not and that their small network is primarily caused by non-participation in
settings such as study, work, leisure and associations. Second, I distinguish locally maintained relationships that have originated
in other settings from locality-based relationships that originated in the neighbourhood. The study shows that high network
localness is more a matter of maintaining relationships in the neighbourhood than forming many new locality-based relationships
with fellow-residents. Third, I examine how the neighbourhood facilitates relationship formation and conclude that this happens
not in “the neighbourhood” but in neighbourhood settings, which attract a particular segment of a neighbourhood population.
I conclude that the problem of network poverty is not in the first place spatial but rather lies in lack of participation
in certain settings. Furthermore, social mixing policies can only be successful if they are accompanied by initiatives to
draw a mixed population to neighbourhood settings and facilitate routine encounters between resource-rich and resource-poor
people. 相似文献
93.
Amr Ahmed Andrew Arnold Luis Pedro Coelho Joshua Kangas Abdul-Saboor Sheikh Eric Xing William Cohen Robert F. Murphy 《Journal of Web Semantics》2010,8(2-3):151-154
The SLIF project combines text-mining and image processing to extract structured information from biomedical literature.SLIF extracts images and their captions from published papers. The captions are automatically parsed for relevant biological entities (protein and cell type names), while the images are classified according to their type (e.g., micrograph or gel). Fluorescence microscopy images are further processed and classified according to the depicted subcellular localization.The results of this process can be queried online using either a user-friendly web-interface or an XML-based web-service. As an alternative to the targeted query paradigm, SLIF also supports browsing the collection based on latent topic models which are derived from both the annotated text and the image data.The SLIF web application, as well as labeled datasets used for training system components, is publicly available at http://slif.cbi.cmu.edu. 相似文献
94.
95.
Amy Murphy 《Journal of Architectural Education》2013,67(2):234-242
Most apocalyptic films are considered dystopian based on their aesthetic terms, yet many of their narratives are structured in such a way to reveal our society's larger utopian desires—particularly in terms of our future relationship with nature, the role of the individual in society, and particular ideals of community life. This article traces several dominant themes found within this genre of cinema as related to contemporary urban design solutions and recent post-disaster strategies, in order to expose what collectively we may be hoping for, as well as still fear. 相似文献
96.
Rosen Craig S.; Murphy Ronald T.; Chow Helen C.; Drescher Kent D.; Ramirez Gil; Ruddy Robyn; Gusman Fred 《Canadian Metallurgical Quarterly》2001,38(2):233
Notes that recovery from combat-related posttraumatic stress disorder (PTSD) is often complicated by unacknowledged problems with alcohol and anger. 102 males combat veterans (aged 42–63 yrs) entering a residential PTSD rehabilitation program completed University of Rhode Island Change Assessment and process-of-change questionnaires based on J. O. Prochaska and C. C. DiClemente's transtheoretical model (TTM; J. O. Prochaska et al, 1992). Separate assessments were made for alcohol abuse and anger control. Four motivational subtypes were identified for both problems. Motivation to change alcohol problems was independent of that for anger. Relative to less-motivated peers highly motivated patients were more like to spontaneously identify alcohol or anger as problems in their life and made greater use of change strategies specified by the TTM. These results support extension of the TTM to anger management and to PTSD management. Treatment implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
GC-MS analysis of the anal sac secretion from the hooded skunk, Mephitis macroura, showed the following seven major components comprised 99% of the volatiles in this secretion: (E)-2-butene-1-thiol, 3-methyl-1-butanethiol, S-(E)-2-butenyl thioacetate, S-3-methylbutenyl thioacetate, 2-phenylethanethiol, 2-methylquinoline, and 2-quinolinemethanethiol. Minor volatile components identified in this secretion are phenylmethanethiol, S-phenylmethyl thioacetate, S-2-phenylethyl thioacetate, bis[(E)-2-butenyl] disulfide, (E)-2-butenyl 3-methylbutyl disulfide, bis(3-methylbutyl) disulfide, and S-2-quinolinemethyl thioacetate. This secretion is similar to that of the striped skunk, Mephitis mephitis, differing only in that it contains four compounds not reported from the striped skunk: phenylmethanethiol, S-phenylmethyl thioacetate, 2-phenylethanethiol, and S-2-phenylethyl thioacetate. 相似文献
98.
Contrary to common belief, back pain amongst young people is a frequent phenomenon. Epidemiological studies have found high prevalence rates of back pain amongst schoolchildren. The investigation reported here aims to validate children's self-reporting and the observation of sitting postures to establish the intensity, duration and frequency of exposure in the classroom. The sitting postures of 18 children were recorded using three methods, the portable ergonomic observation method (PEO), video analysis and self-report. The three methods were compared. PEO was significantly correlated with video analysis of the sitting postures after development of the method. Self-report was not significantly correlated with video analysis of the sitting postures. Therefore PEO was selected as the main observation tool in further analysis of children's sitting posture in schools in South-East England as part of a large research programme investigating back pain amongst schoolchildren. 相似文献
99.
Killen Joel D.; Fortmann Stephen P.; Murphy Greer M. Jr.; Hayward Chris; Arredondo Christina; Cromp DeAnn; Celio Maria; Abe Laurie; Wang Yun; Schatzberg Alan F. 《Canadian Metallurgical Quarterly》2006,74(2):286
The authors present results of a randomized clinical trial of the efficacy of extended treatment with bupropion SR in producing longer term cigarette smoking cessation. Adult smokers (N = 362) received open-label treatment (11 weeks) that combined relapse prevention training, bupropion SR, and nicotine patch followed by extended treatment (14 weeks) with bupropion SR or matching placebo. Abstinence percentages were relatively high (week 11: 52%; week 25: bupropion, 42%; placebo, 38%; week 52: bupropion, 33%; placebo, 34%), but bupropion SR did not surpass placebo. Gender and baseline craving level were identified as significant, independent moderators of treatment response. Men were more likely to abstain than women (week 11: 59% vs. 43%, p = .001; week 25: 48% vs. 31%, p = .001; week 52: 39% vs. 27%, p = .01). Because most smokers suffer relapse with any current cessation treatment, the comparatively high abstinence percentages achieved in this trial are of interest. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Taft Casey T.; O'Farrell Timothy J.; Torres Sandra E.; Panuzio Jillian; Monson Candice M.; Murphy Marie; Murphy Christopher M. 《Canadian Metallurgical Quarterly》2006,20(4):581
In this study, the authors examined the correlates of psychological aggression victimization and perpetration among a community sample of 145 heterosexual couples. For both women and men, psychological aggression victimization was associated with greater psychological distress, anxiety, and physical health symptoms beyond the effects of physical aggression. Psychological aggression victimization was also uniquely associated with higher levels of depression for women. Trait anger and poor relationship adjustment were the strongest correlates of psychological aggression perpetration across genders. Childhood father-to-child and father-to-mother aggressions were associated with psychological aggression perpetration for men only, suggesting possible distinct etiologies across genders. These data highlight the importance of the further development of models for psychological aggression in both women and men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献