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91.
There is a widespread belief that information and communication technologies (ICTs) can play a significant role in the socio-economic development of a developing country. ICT has the potential to affect many aspects of economic and societal activities such as GDP growth, employment, productivity, poverty alleviation, quality of life, education, and healthcare. While the literature provides a myriad of definitions and elements of socio-economic development, the focus tends to be on theoretical conceptualizations from various disciplines and impacts from isolated individual projects. In particular, the impact of ICT on socio-economic development has not been carefully examined from the viewpoint of the ultimate stakeholder, the citizens of a country, who are the final consumers of the technology. This study fills this gap by focusing on the citizens’ view in describing ICT-driven socio-economic development in a developing country. A theoretical framework influenced by the “capabilities approach” was developed to guide this research, and the interpretive stance was used to conduct the study. More specifically, the narrative research method, which is seldom used in IS research but is appropriate for this study, was used. Narratives allow deeper and profound insights into social representations and participants' beliefs about the role of ICT in socio-economic development. Using this methodology, a model of the impact dimensions of socio-economic development is presented. 相似文献
92.
Ejaz Ahmed Anjum Naveed Siti Hafizah Ab Hamid Abdullah Gani Khaled Salah 《The Journal of supercomputing》2017,73(10):4466-4492
Mobile cloud computing augments the resource-constrained mobile devices to run rich mobile applications by leveraging the cloud resources and services. Compute-intensive mobile apps require significant communication resources for migrating the code from mobile devices to the cloud. For such apps, distributed application execution frameworks (DAEF) have been proposed in the literature. These frameworks either migrate the mobile app code during runtime or keep the app synchronized with another remotely executed app on the cloud. Frameworks also support mobile app live migration to cater for compute node mobility. One key research question arises is how successful are these DAEFs in achieving the seamless application execution under various network conditions? The answer to this question entails formal analysis of the DAEFs to determine the realistic bounds on propagation delay, bandwidth and application interaction with mobile device for various types and sizes of apps. In this research, we apply formal analysis techniques to define the execution time of the app and the time required for code migration. We also define three conditions for seamless application execution. Given realistic values for processor speed, application executable size, possible number of executed instructions, network propagation delay and transmission delay, we show what components of the mobile app need to be migrated during execution to the cloud. Finally, we compute realistic bounds for the app size (that can be executed seamlessly) based on important features which include cloud and device resources, bandwidth and latency profile. 相似文献
93.
Sara Abbaspour Asadollah Daniel Sundmark Sigrid Eldh Hans Hansson Wasif Afzal 《Software Quality Journal》2017,25(1):49-82
Debugging—the process of identifying, localizing and fixing bugs—is a key activity in software development. Due to issues such as non-determinism and difficulties of reproducing failures, debugging concurrent software is significantly more challenging than debugging sequential software. A number of methods, models and tools for debugging concurrent and multicore software have been proposed, but the body of work partially lacks a common terminology and a more recent view of the problems to solve. This suggests the need for a classification, and an up-to-date comprehensive overview of the area. This paper presents the results of a systematic mapping study in the field of debugging of concurrent and multicore software in the last decade (2005–2014). The study is guided by two objectives: (1) to summarize the recent publication trends and (2) to clarify current research gaps in the field. Through a multi-stage selection process, we identified 145 relevant papers. Based on these, we summarize the publication trend in the field by showing distribution of publications with respect to year, publication venues, representation of academia and industry, and active research institutes. We also identify research gaps in the field based on attributes such as types of concurrency bugs, types of debugging processes, types of research and research contributions. The main observations from the study are that during the years 2005–2014: (1) there is no focal conference or venue to publish papers in this area; hence, a large variety of conferences and journal venues (90) are used to publish relevant papers in this area; (2) in terms of publication contribution, academia was more active in this area than industry; (3) most publications in the field address the data race bug; (4) bug identification is the most common stage of debugging addressed by articles in the period; (5) there are six types of research approaches found, with solution proposals being the most common one; and (6) the published papers essentially focus on four different types of contributions, with “methods” being the most common type. We can further conclude that there are still quite a number of aspects that are not sufficiently covered in the field, most notably including (1) exploring correction and fixing bugs in terms of debugging process; (2) order violation, suspension and starvation in terms of concurrency bugs; (3) validation and evaluation research in the matter of research type; (4) metric in terms of research contribution. It is clear that the concurrent, parallel and multicore software community needs broader studies in debugging. This systematic mapping study can help direct such efforts. 相似文献
94.
Tariq Umer Muhammad Khalil Afzal Ehsan Ullah Munir Muhammad Alam 《Wireless Personal Communications》2018,98(1):105-118
Vehicular ad-hoc network (VANET) is characterized as a highly dynamic wireless network due to the dynamic connectivity of the network nodes. To achieve better connectivity under such dynamic conditions, an optimal transmission strategy is required to direct the information flow between the nodes. Earlier studies on VANET’s overlook the characteristics of heterogeneity in vehicle types, traffic structure, flow for density estimation, and connectivity observation. In this paper, we have proposed a heterogeneous traffic flow based dual ring connectivity model to enhance both the message disseminations and network connectivity. In our proposed model the availability of different types of vehicles on the road, such as, cars, buses, etc., are introduced in an attempt to propose a new communication structure for moving vehicles in VANETl under cooperative transmission in heterogeneous traffic flow. The model is based on the dual-ring structure that forms the primary and secondary rings of vehicular communication. During message disseminations, Slow speed vehicles (buses) on the secondary ring provide a backup path of communication for high speed vehicles (cars) moving on the primary ring. The Slow speed vehicles act as the intermediate nodes in the aforementioned connectivity model that helps improve the network coverage and end-to-end data delivery. For the evaluation and the implementation of dual-ring model a clustering routing scheme warning energy aware cluster-head is adopted that also caters for the energy optimization. The implemented dual-ring message delivery scheme under the cluster-head based routing technique does show improved network coverage and connectivity dynamics even under the multi-hop communication system. 相似文献
95.
Guido H. Jajamovich Wei Huang Cecilia Besa Xin Li Aneela Afzal Hadrien A. Dyvorne Bachir Taouli 《Magma (New York, N.Y.)》2016,29(1):49-58
Objective
To quantify hepatocellular carcinoma (HCC) perfusion and flow with the fast exchange regime-allowed Shutter-Speed model (SSM) compared to the Tofts model (TM).Materials and methods
In this prospective study, 25 patients with HCC underwent DCE-MRI. ROIs were placed in liver parenchyma, portal vein, aorta and HCC lesions. Signal intensities were analyzed employing dual-input TM and SSM models. ART (arterial fraction), K trans (contrast agent transfer rate constant from plasma to extravascular extracellular space), v e (extravascular extracellular volume fraction), k ep (contrast agent intravasation rate constant), and τ i (mean intracellular water molecule lifetime) were compared between liver parenchyma and HCC, and ART, K trans, v e and k ep were compared between models using Wilcoxon tests and limits of agreement. Test–retest reproducibility was assessed in 10 patients.Results
ART and v e obtained with TM; ART, v e , k e and τ i obtained with SSM were significantly different between liver parenchyma and HCC (p < 0.04). Parameters showed variable reproducibility (CV range 14.7–66.5 % for both models). Liver K trans and v e ; HCC v e and k ep were significantly different when estimated with the two models (p < 0.03).Conclusion
Our results show differences when computed between the TM and the SSM. However, these differences are smaller than parameter reproducibilities and may be of limited clinical significance.96.
97.
Khurram Shehzad Akhtar Ali Afzal Wardah Anam Zulfiqar Ali Tanveer Hussain 《纺织学会志》2020,111(4):555-564
AbstractIn this study, the physical–mechanical properties of ring spun, ring compact, rotor and air-vortex yarns were investigated. The study was carried with yarn having linear densities of 24.4 tex and 36.7 tex, which were then converted to woven fabrics. The ring spun yarns have higher values of strength but also with higher strength irregularities. Extra-ordinarily low hairiness was observed in air-vortex yarns due to its unique yarn formation technique. The deviation rate (DR) of yarns have correlation with the mass spectrogram of respective yarns obtained from USTER Tester 5. Rotor and air-vortex yarns exhibited higher coefficient of friction. The woven fabrics made from ring spun yarns exhibited higher tensile and tear strength with higher elongation at break. The fabrics made from air-vortex yarns have very good pilling grade due to less protruding fibres on their surface and good structural integrity. 相似文献
98.
Peng Du Kai Huang Xiaoyuan Fan Jingteng Ma Naveed Hussain Ruyue Wang Bohan Deng Binghui Ge Haolin Tang Ru Zhang Ming Lei Hui Wu 《Nano Research》2022,(4):3065-3072
Being a typical state of the art heterogeneous catalyst,supported noble metal catalyst often demonstrates enhanced catalytic properties.However,a facile synthet... 相似文献
99.
Saima Shakil Malik Ayesha Saeed Mehreen Baig Naveed Asif Nosheen Masood Azra Yasmin 《International Journal of Food Properties》2018,21(1):655-666
Breast cancer is one of the most important causes of cancer related morbidity and mortality in the world. Along with genetic, environmental factors also play a multifaceted role in the development of disease. Breast contains several bacterial species performing specialized functions. Probiotics, as functional food, play pivotal role against breast cancer development in vivo and in vitro. Current review summarized all the available data related to diet, probiotics, and their association with breast cancer risk along with underlying mechanisms. Presently, it was believed that many of the commercially available probiotic products were safe to use and had some beneficial health effects for the host. Probiotics had a potential to act against breast cancer progression evidenced by many animal model and cell-based experiments. Some probiotics strains may be useful as an adjuvant therapy for breast cancer prevention or treatment, by modulating immune response or breast microbial community. However, large-scale clinical trials and intense research are mandatory to explore probiotics-related metabolic and molecular mechanisms in breast cancer. 相似文献
100.