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排序方式: 共有4410条查询结果,搜索用时 15 毫秒
61.
Hannes Holm Markus Buschle Robert Lagerström Mathias Ekstedt 《Software and Systems Modeling》2014,13(2):825-841
Enterprise Architecture (EA) is an approach used to provide decision support based on organization-wide models. The creation of such models is, however, cumbersome as multiple aspects of an organization need to be considered, making manual efforts time-consuming, and error prone. Thus, the EA approach would be significantly more promising if the data used when creating the models could be collected automatically—a topic not yet properly addressed by either academia or industry. This paper proposes network scanning for automatic data collection and uses an existing software tool for generating EA models (ArchiMate is employed as an example) based on the IT infrastructure of enterprises. While some manual effort is required to make the models fully useful to many practical scenarios (e.g., to detail the actual services provided by IT components), empirical results show that the methodology is accurate and (in its default state) require little effort to carry out. 相似文献
62.
Tiyapiboonchaiya C Pringle JM Sun J Byrne N Howlett PC MacFarlane DR Forsyth M 《Nature materials》2004,3(1):29-32
The future of lithium metal batteries as a widespread, safe and reliable form of high-energy-density rechargeable battery depends on a significant advancement in the electrolyte material used in these devices. Molecular solvent-based electrolytes have been superceded by polymer electrolytes in some prototype devices, primarily in a drive to overcome leakage and flammability problems, but these often exhibit low ionic conductivity and prohibitively poor lithium-ion transport. To overcome this, it is necessary to encourage dissociation of the lithium ion from the anionic polymer backbone, ideally without the introduction of competing, mobile ionic species. Here we demonstrate the effect of zwitterionic compounds, where the cationic and anionic charges are immobilized on the same molecule, as extremely effective lithium ion 'dissociation enhancers'. The zwitterion produces electrolyte materials with conductivities up to seven times larger than the pure polyelectrolyte gels, a phenomenon that appears to be common to a number of different copolymer and solvent systems. 相似文献
63.
Radiocarbon ((14)C) is an ideal tracer for in vivo human ADME (absorption, distribution, metabolism, elimination) and PBPK (physiological-based pharmacokinetic) studies. Living plants peferentially incorporate atmospheric (14)CO(2) versus (13)CO(2) versus (12)CO(2), which result in unique signature. Furthermore, plants and the food chains they support also have unique carbon isotope signatures. Humans, at the top of the food chain, consequently acquire isotopic concentrations in the tissues and body fluids depending on their dietary habits. In preparation of ADME and PBPK studies, 12 healthy subjects were recruited. The human baseline (specific to each individual and their diet) total carbon (TC) and carbon isotope (13)C (δ(13)C) and (14)C (F(m)) were quantified in whole blood (WB), plasma, washed red blood cell (RBC), urine, and feces. TC (mg of C/100 μL) in WB, plasma, RBC, urine, and feces were 11.0, 4.37, 7.57, 0.53, and 1.90, respectively. TC in WB, RBC, and feces was higher in men over women, P < 0.05. Mean δ(13)C were ranked low to high as follows: feces < WB = plasma = RBC = urine, P < 0.0001. δ(13)C was not affected by gender. Our analytic method shifted δ(13)C by only ±1.0 ‰ ensuring our F(m) measurements were accurate and precise. Mean F(m) were ranked low to high as follows: plasma = urine < WB = RBC = feces, P < 0.05. F(m) in feces was higher for men over women, P < 0.05. Only in WB, (14)C levels (F(m)) and TC were correlated with one another (r = 0.746, P < 0.01). Considering the lag time to incorporate atmospheric (14)C into plant foods (vegetarian) and or then into animal foods (nonvegetarian), the measured F(m) of WB in our population (recruited April 2009) was 1.0468 ± 0.0022 (mean ± SD), and the F(m) of WB matched the (extrapolated) atmospheric F(m) of 1.0477 in 2008. This study is important in presenting a procedure to determine a baseline for a study group for human ADME and PBPK studies using (14)C as a tracer. 相似文献
64.
We consider Facebook unfriending as a form of relationship termination with negative emotional and cognitive consequences. Specifically, ruminative and negative emotional responses are examined via an online survey of adult Facebook users who were unfriended. These responses were positively related to each other and to Facebook intensity. Rumination was positively predicted by using Facebook to connect with existing contacts and was more likely when the unfriender was a close partner. Participants also responded with greater rumination and negative emotion when they knew who unfriended them, when they thought they were unfriended for Facebook-related reasons, and when participants initiated the Facebook friend request. The contribution of these exploratory findings to our growing understanding of negative relational behaviors on Facebook are discussed. 相似文献
65.
Per Närman Hannes Holm Mathias Ekstedt Nicholas Honeth 《The Journal of Strategic Information Systems》2013,22(1):70-85
Insights into service response time is important for service-oriented architectures and service management. However, directly measuring the service response time is not always feasible or can be very costly. This paper extends an analytical modeling method which uses enterprise architecture modeling to support the analysis. The extensions consist of (i) a formalization using the Hybrid Probabilistic Relational Model formalism, (ii) an implementation in an analysis tool for enterprise architecture and (iii) a data collection approach using expert assessments collected via interviews and questionnaires. The accuracy and cost effectiveness of the method was tested empirically by comparing it with direct performance measurements of five services of a geographical information system at a Swedish utility company. The tests indicate that the proposed method can be a viable option for rapid service response time estimates when a moderate accuracy within 15% is sufficient. 相似文献
66.
Theodor Holm Nelson 《New Review of Hypermedia and Multimedia》2013,19(1):3-5
Web page annotation and adaptive navigation support are two active, but independent research directions focused on the same goal: expanding the functionality of the Web as a hypertext system. The goal of the AnnotatEd system presented in this paper has been to integrate annotation and adaptive navigation support into a single value-added service where the components can reinforce each other and create new unique attributes. This paper describes the implementation of AnnotatEd from early prototypes to the current version, which has been explored in several contexts. We summarize some lessons we learned during the development process and which defined the current functionality of the system. We also present the results of several classroom studies of the system. These results demonstrate the importance of the browsing-based information access supported by AnnotatEd and the value of both the annotation and navigation support functionalities offered by the system. 相似文献
67.
Jennifer A. Kam 《The Journal of communication》2011,61(3):455-475
Language brokering is the communication process where individuals with no formal training (often children of immigrant families) linguistically mediate for 2 or more parties (usually adult family members and individuals from mainstream culture). This study examined the direct and indirect effects of language brokering on mental health and risky behaviors. Mexican‐heritage youth (N = 684) from schools in Phoenix, AZ, completed surveys at 3 waves from 7th through 8th grades. Language brokering frequency and negative brokering feelings were positively associated with family‐based acculturation stress, which was positively associated with alcohol use and other risky behaviors. Yet, brokering frequency was negatively associated with other risky behaviors, and positive brokering feeling was negatively associated with cigarette use. Implications for these findings are discussed. 相似文献
68.
Coelho Jennifer; Roefs Anne; Havermans Remco; Salvy Sarah-Jeanne; Jansen Anita 《Canadian Metallurgical Quarterly》2011,43(1):63
Psychological processes may play a role in the evaluation of the effectiveness of exercise and subsequent food intake. In order to further investigate this phenomenon, the effects of the timing of exercise relative to an eating opportunity were evaluated. Female undergraduate participants who were of average weight and did not exercise regularly were randomly assigned to one of three conditions (exercise before eating [n = 10], exercise after eating [n = 11], or no exercise [n = 12]). Expectations of the effectiveness of the exercise, value of dieting, and intake were assessed. Participants who exercised after eating had higher expectations of the effectiveness of the exercise than those who exercised before eating, while those who exercised before eating reported valuing dieting more than controls. No effects on intake emerged; therefore, there appears to be a disconnect between dieting appraisals and actual eating behaviour. The results are discussed in relation to theories on conflicting goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Lee Jennifer E. C.; Sudom Kerry A.; McCreary Donald R. 《Canadian Metallurgical Quarterly》2011,43(3):222
Psychological resilience is an important construct for those who work in high-stress, potentially traumatic occupations. Using data collected as part of the Canadian Forces (CF) Recruit Health Questionnaire (RHQ), structural equation modelling analyses were performed to test the fit of a model of resilience comprised of several intrapersonal resilience factors (i.e., Big Five personality traits, dispositional affect, dispositional optimism, hardiness, mastery, self-esteem) and one interpersonal resilience factor (i.e., social support). An initial model showed that all lower-order intrapersonal variables loaded significantly onto a higher-order intrapersonal resilience latent factor, and that this factor was significantly correlated with social support. However, the strong intercorrelations between a few of the intrapersonal variables pointed to some redundancy. Based on empirical data and on a conceptual analysis, an alternative, more parsimonious model of resilience was developed. This model consisted of the Big Five personality traits, positive affect, and mastery as lower-order factors of dispositional resilience, which was hypothesised to be correlated with social support. This analysis is an important first step to developing an approach to conceptualise and measure resilience. One benefit of being able to assess resilience is that doing so can inform the development of programs to enhance mental health, readiness and recovery. However, more research is needed to understand the processes through which these psychological factors influence occupational as well as health outcomes before relevant policies may be developed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
70.
The number of individual items that can be maintained in working memory is limited. One solution to this problem is to store representations of ensembles that contain summary information about large numbers of items (e.g., the approximate number or cumulative area of a group of many items). Here we explored the developmental origins of ensemble representations by asking whether infants represent ensembles and, if so, how many at one time. We habituated 9-month-old infants to arrays containing 2, 3, or 4 spatially intermixed colored subsets of dots, then asked whether they detected a numerical change to one of the subsets or to the superset of all dots. Experiment Series 1 showed that infants detected a numerical change to 1 of the subsets when the array contained 2 subsets but not 3 or 4 subsets. Experiment Series 2 showed that infants detected a change to the superset of all dots no matter how many subsets were presented. Experiment 3 showed that infants represented both the approximate number and the cumulative surface area of these ensembles. Our results suggest that infants, like adults (Halberda, Sires, & Feigenson, 2006), can store quantitative information about 2 subsets plus the superset: a total of 3 ensembles. This converges with the known limit on the number of individual objects infants and adults can store and suggests that, throughout development, an ensemble functions much like an individual object for working memory. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献