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81.
82.
Ratner David Reiher Peter Popek Gerald J. Kuenning Geoffrey H. 《Mobile Networks and Applications》2001,6(6):525-533
Replication is extremely important in mobile environments because nomadic users require local copies of important data. However, today's replication systems are not mobile-ready. Instead of improving the mobile user's environment, the replication system actually hinders mobility and complicates mobile operation. Designed for stationary environments, the replication services do not and cannot provide mobile users with the capabilities they require. Replication in mobile environments requires fundamentally different solutions than those previously proposed, because nomadicity presents a fundamentally new and different computing paradigm. Here we outline the requirements that mobility places on the replication service, and briefly describe ROAM, a system designed to meet those requirements. 相似文献
83.
Information technology (IT) in Saudi Arabia: Culture and the acceptance and use of IT 总被引:2,自引:0,他引:2
The unified theory of acceptance and use of technology (UTAUT), a model of the user acceptance of IT, synthesizes elements from several prevailing user acceptance models. It has been credited with explaining a larger proportion of the variance of ‘intention to use’ and ‘usage behavior’ than do preceding models. However, it has not been validated in non-Western cultures. Using a survey sample collected from 722 knowledge workers using desktop computer applications on a voluntary basis in Saudi Arabia, we examined the relative power of a modified version of UTAUT in determining ‘intention to use’ and ‘usage behavior’. We found that the model explained 39.1% of intention to use variance, and 42.1% of usage variance. In addition, drawing on the theory of cultural dimensions, we hypothesized and tested the similarities and differences between the North American and Saudi validations of UTAUT in terms of cultural differences that affected the organizational acceptance of IT in the two societies. 相似文献
84.
用于图像传感器制造的光刻技术 总被引:1,自引:0,他引:1
Geoffrey Phillipps Rudy Pellens 《中国集成电路》2007,16(1):47-51
引言任何一种数字成像的核心都是图像传感器。它的基本结构包括一个能把光转换为图像的有源像素矩阵。数码相机和带相机的移动电话带动了图像传感器需求市场的快速增长,它们已成为主要IC制造商大量生产的产品之一。制造成像阵列通常采用两种主要的工艺技术——电荷耦合器件(CCD)和CMOS图像传感器(CIS)。在形成工艺层次组合和电学设计方面,这两种技术有很大差别。但是,两者都需要优化,以俘获到达的光线,并将其更有效地转化为电信号。CCD器件在象素区把光子转换为电荷。CIS器件则可以看作为改进的存储器单元,每一单元包含一个可以产生… 相似文献
85.
Williams Geoffrey C.; Lynch Martin; Glasgow Russell E. 《Canadian Metallurgical Quarterly》2007,26(6):728
Objective: To determine if a patient-centered, computer-assisted diabetes care intervention increased perceived autonomy support, perceived competence (from self-determination theory), and if these constructs mediated the effect of the intervention on ADA/NCQA recommended diabetes care outcomes. Design: A randomized controlled trial of 866 adult type 2 diabetes patients in heterogeneous primary care settings in Colorado. Main Outcome Measures: Perceived autonomy support, perceived competence, patient satisfaction, glycemic control (HbA1c), ratio of total to HDL cholesterol, diabetes distress, and depressive symptoms. Results: The computer-assisted intervention increased patient perception of autonomy support relative to a computer-based control condition ( p = .05). Change in perceived competence partially mediated the effects of increased autonomy support on the change in lipids, diabetes distress, and depressive symptoms. The construct of autonomy support was found to be separate from that of patient satisfaction. Conclusions: A patient-centered, computer-assisted intervention was effective in improving diabetes self-management outcomes, in part, because it increased patients' perception that their autonomy was supported which changed perceived competence. These findings support the self-determination model for health behavior change and the chronic care model and support the further study of the use of these technologies to motivate patients to improve their health outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Stigmatization can give rise to belonging uncertainty. In this state, people are sensitive to information diagnostic of the quality of their social connections. Two experiments tested how belonging uncertainty undermines the motivation and achievement of people whose group is negatively characterized in academic settings. In Experiment 1, students were led to believe that they might have few friends in an intellectual domain. Whereas White students were unaffected, Black students (stigmatized in academics) displayed a drop in their sense of belonging and potential. In Experiment 2, an intervention that mitigated doubts about social belonging in college raised the academic achievement (e.g., college grades) of Black students but not of White students. Implications for theories of achievement motivation and intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
May Yau Michelle Carver Luis Alvarez Geoffrey A. Block Glenn M. Chertow 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(2):235-241
Despite superior outcomes and lower associated costs, relatively few patients with end‐stage renal disease undergo self‐care or home hemodialysis. Few studies have examined patient‐ and physician‐specific barriers to self‐care and home hemodialysis in the modern era. The degree to which innovative technology might facilitate the adoption of these modalities is unknown. We surveyed 250 patients receiving in‐center hemodialysis and 51 board‐certified nephrologists to identify key barriers to adoption of self‐care and home hemodialysis. Overall, 172 (69%) patients reported that they were “likely” or “very likely” to consider self‐care hemodialysis if they were properly trained on a new hemodialysis system designed for self‐care or home use. Nephrologists believed that patients were capable of performing many dialysis‐relevant tasks, including: weighing themselves (98%), wiping down the chair and machine (84%), clearing alarms during treatment (53%), taking vital signs (46%), and cannulating vascular access (41%), but thought that patients would be willing to do the same in only 69%, 34%, 31%, 29%, and 16%, respectively. Reasons that nephrologists believe patients are hesitant to pursue self‐care or home hemodialysis do not correspond in parallel or by priority to reasons reported by patients. Self‐care and home hemodialysis offer several advantages to patients and dialysis providers. Overcoming real and perceived barriers with new technology, education and coordinated care will be required for these modalities to gain traction in the coming years. 相似文献
88.
Object-based change detection 总被引:1,自引:0,他引:1
Gang Chen Geoffrey J. Hay Luis M. T. Carvalho Michael A. Wulder 《International journal of remote sensing》2013,34(14):4434-4457
Characterizations of land-cover dynamics are among the most important applications of Earth observation data, providing insights into management, policy and science. Recent progress in remote sensing and associated digital image processing offers unprecedented opportunities to detect changes in land cover more accurately over increasingly large areas, with diminishing costs and processing time. The advent of high-spatial-resolution remote-sensing imagery further provides opportunities to apply change detection with object-based image analysis (OBIA), that is, object-based change detection (OBCD). When compared with the traditional pixel-based change paradigm, OBCD has the ability to improve the identification of changes for the geographic entities found over a given landscape. In this article, we present an overview of the main issues in change detection, followed by the motivations for using OBCD as compared to pixel-based approaches. We also discuss the challenges caused by the use of objects in change detection and provide a conceptual overview of solutions, which are followed by a detailed review of current OBCD algorithms. In particular, OBCD offers unique approaches and methods for exploiting high-spatial-resolution imagery, to capture meaningful detailed change information in a systematic and repeatable manner, corresponding to a wide range of information needs. 相似文献
89.
90.
Gang Chen Kaiguang Zhao Gregory J. McDermid Geoffrey J. Hay 《International journal of remote sensing》2013,34(9):2909-2924
Geographically weighted regression (GWR) extends the conventional ordinary least squares (OLS) regression technique by considering spatial nonstationarity in variable relationships and allowing the use of spatially varying coefficients in linear models. Previous forest studies have demonstrated the better performance of GWR compared to OLS when calibrated and validated at sampled locations where field measurements are collected. However, the use of GWR for remote-sensing applications requires generating estimates and evaluating the model performance for the large image scene, not just for sampled locations. In this study, we introduce GWR to estimate forest canopy height using high spatial resolution Quickbird (QB) imagery and evaluate the influence of sampling density on GWR. We also examine four commonly used spatial analysis techniques – OLS, inverse distance weighting (IDW), ordinary kriging (OK) and cokriging (COK) – and compare their performance with that using GWR. Results show that (i) GWR outperformed OLS at all sampling densities; however, they produced similar results at low sampling densities, suggesting that GWR may not produce significantly better results than OLS in remote-sensing operational applications where only a small number of field data are collected. (ii) The performance of GWR was better than those of IDW, OK and COK at most sampling densities. Among the spatial interpolation techniques we examined, IDW was the best to estimate the canopy height at most densities, while COK outperformed OK only marginally and produced larger canopy height estimation errors than both IDW and GWR. (iii) GWR had the advantage of generating canopy height estimation maps with more accurate estimates than OLS, and it preserved patterns of geographic features better than IDW, OK or COK. 相似文献