Internet addiction: Meta-synthesis of qualitative research for the decade 1996–2006

Internet addiction is “an individual’s inability to control their Internet use, which in turn leads to feelings of distress and functional impairment of daily activities” [Shapira, N., Lessig, M., Goldsmith, T., Szabo, S., Lazoritz, M., Gold, M. et al. (2003). Problematic Internet use: Proposed classification and diagnostic criteria. Depression and Anxiety, 17(4), 207–216]. Previous research in this field has offered inconclusive data on whether Internet addiction can be classified as a disorder. This study provides an in-depth and comprehensive analysis of internet addiction through a meta-synthesis of qualitative studies on excessive Internet use published during the period of 1996–2006. Several constructs pertaining to the domain of Internet addiction have been identified and a theoretical model of Internet addiction has been proposed.     

Hierarchical control of multiple resources in distributed real-time and embedded systems

Real-time and embedded systems have traditionally been designed for closed environments where operating conditions, input workloads, and resource availability are known a priori, and are subject to little or no change at runtime. There is increasing demand, however, for adaptive capabilities in distributed real-time and embedded (DRE) systems that execute in open environments where system operational conditions, input workload, and resource availability cannot be characterized accurately a priori. A challenging problem faced by researchers and developers of such systems is devising effective adaptive resource management strategies that can meet end-to-end quality of service (QoS) requirements of applications. To address key resource management challenges of open DRE systems, this paper presents the Hierarchical Distributed Resource-management Architecture (HiDRA), which provides adaptive resource management using control techniques that adapt to workload fluctuations and resource availability for both bandwidth and processor utilization simultaneously. This paper presents three contributions to research in adaptive resource management for DRE systems. First, we describe the structure and functionality of HiDRA. Second, we present an analytical model of HiDRA that formalizes its control-theoretic behavior and presents analytical assurance of system performance. Third, we evaluate the performance of HiDRA via experiments on a representative DRE system that performs real-time distributed target tracking. Our analytical and empirical results indicate that HiDRA yields predictable, stable, and efficient system performance, even in the face of changing workload and resource availability.     

顾客不嫌信息多

很多公司的在线销售增长情况不理想,领导者在失望之余认为原因是在线客户的忠诚度不高,消费意愿也不强。殊不知,在线销售不如人意的真实原因并非如此,而是公司没能充分发掘客户最为看重的价值点——参与感。     

Scale cross-ambiguity and target resolution

We derive the correct formulation of the Doppler problem in which the received signal is scaled in time by a scale factor dependent on the relative radial velocity of the transmitter and the receiver, normalized by the propagation speed in the transmission medium. For sine waves, the conventional Doppler model in which the received signal is translated in frequency is equivalent to the scale model. However, for signals with non zero bandwidth, the difference can be quite significant, as we demonstrate. We further demonstrate simple methods, based on the discrete Fourier transform (DFT) and phase differentiation of the scale CAF, by which delay and scale may be accurately estimated.     

Scintillator‐based flat‐panel x‐ray imaging detectors

Abstract— Large‐area amorphous‐silicon flat‐panel x‐ray imaging detectors were introduced commercially about 10 years ago and have seen a steady increase in both volume and number of applications since. The flat‐panel‐detector industry was made possible by manufacturing methods and equipment first developed for the display industry. Here, the different types of flat‐panel detectors are described, with focus on the scintillator‐based TFT/photodiode detector. The manufacturing process used for these detectors is explained and compared to that for displays. Detector operation is detailed, and the various medical and industrial applications are described. Finally, the performance metrics for these detectors and the impact of the performance requirements on detector design are discussed.     

Developing Sustainable Research Networks in Graduate Education

The traditional modes of knowledge production and circulation in academia are (slowly but surely) shifting from the hierarchical, top-down systems of print to the distributed, bottom-up systems of the Web. It is in the context of these shifts and the rapid development of Web 2.0 tools and methods that we argue for a concomitant shift in the predominant practices of graduate education in rhetoric—particularly for students of digital rhetoric. In this article, we describe the development of a research network that combines the power of digital networking with the collaborative facilitation offered by communities of practice and consider how research networks can be grown and sustained as part of the graduate education of technorhetoricians.     

Intuitive robust stability metric for PID control of self-regulating processes

Published methods establish how plant-model mismatch in the process gain and dead time impacts closed-loop stability. However, these methods assume no plant-model mismatch in the process time constant. The work presented here proposes the robust stability factor metric, RSF, to examine the effect of plant-model mismatch in the process gain, dead time, and time constant. The RSF is presented in two forms: an equation form and a visual form displayed on robustness plots derived from the Bode and Nyquist stability criteria. This understanding of robust stability is reinforced through visual examples of how closed-loop performance changes with various levels of plant-model mismatch. One example shows how plant-model mismatch in the time constant can impact closed-loop stability as much as plant-model mismatch in the gain and/or dead time. Theoretical discussion shows that the impact is greater for small dead time to time constant ratios. As the closed-loop time constant used in Internal Model Control (IMC) tuning decreases, the impact becomes significant for a larger range of dead time to time constant ratios. To complete the presentation, the RSF is used to compare the robust stability of IMC-PI tuning to other PI, PID, and PID with Filter tuning correlations.     

Shape disassembly using generating merging probability

Computer integrated manufacturing uses computer technology to integrate a manufacturing system through a man-machine interface that fills the gap between manual operation and machine processes. It is clear that a computer vision-based man-machine interface makes a fully automated system possible. The basic challenge of a vision-based interface is how to extract information from digitized images and convert it to machine-friendly knowledge. To extract information, then, it often end up to the problem of shape decomposition. This paper proposes an new approach in decomposing compound shapes without prior knowledge of the scene. The proposed algorithm exploits the fact that planar shapes can be completely described by contour segments, and can be decomposed at their maximum concavity into simpler objects. To reduce spurious decomposition, the decomposed segments are merged into groups by analyzing and utilizing the merging hypotheses. The algorithm calculates the linking possibility by weighting the angular differentiation between two segments. The techniques are implemented and are applied to other partial shape matching problems for clustering purposes.     

Viral interleukin 10 (IL-10), the human herpes virus 4 cellular IL-10 homologue, induces local anergy to allogeneic and syngeneic tumors

After the cloning of murine cytokine synthesis inhibitory factor, it was recognized that a homologous open reading frame was encoded within the Epstein-Barr virus (human herpes virus 4). This viral protein has now been termed viral interleukin 10 (vIL-10) to reflect its protein sequence homology to "cellular" IL-10 (cIL-10, either murine or human IL-10). It is now widely accepted that vIL-10 shares many functions with cIL-10, principally, the ability to enhance survival of newly infected B cells and to diminish the production of IFN-gamma and IL-2 during ongoing immune reactions. The immunomodulatory effect of locally secreted vIL-10 and murine IL-10 (mIL-10) was examined in tumor models using CL8-1 (a BL6 melanoma cell line transfected with the H-2Kb class I gene) in syngeneic animals. Although parental BL6 tumor cells grow in immunocompetent syngeneic hosts, CL8-1 are rejected. To achieve local secretion of vIL-10, we generated vIL-10 retroviral vectors. While nontransduced CL8-1 cells (1 x 10(4)) failed to grow when injected intradermally in C57BL/6 mice, CL8-1 cells (1 x 10(4)) transduced with vIL-10 formed palpable tumors and eventually killed 80% of injected animals. Suppression of tumor rejection was also noted when CL8-1 tumors with or without vIL-10 transfection were admixed with syngeneic vIL-10-transfected fibroblasts and inoculated. Since the in vitro proliferation of the tumor was not altered after transduction with the vIL-10 gene and injection of vIL-10-transduced CL8-1 does not affect the rejection of nontransduced CL8-1 inoculated at a distant site, local vIL-10 secretion appears to suppress the process of immune rejection of the target cells in a dose-dependent manner. Similar results were observed for the H-2b MCA105 sarcoma tumor model in allogeneic BALB/c mice (H-2d). Although all animals that received nontransfected MCA105 rapidly rejected these tumors, MCA105 sarcomas transfected with vIL-10 remained palpable for up to 37 d. The local immunosuppressive effect of gene-delivered vIL-10 could be neutralized by anti-human IL-10 monoclonal antibody or could be reversed by the systemic administration of IL-2 or IL-12. In marked contrast, mIL-10 transfection of CL8-1 significantly suppressed tumor growth and frequently led to the rejection of tumor. Similar results were obtained for the murine tumor cell lines MCA102.(ABSTRACT TRUNCATED AT 400 WORDS)