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161.
Much of research in intelligent programming systems for users has been polarized towards two opposite domains: active and passive approaches to diagnosis. The advocates of the active approach claim that much of the effectiveness of intelligent program systems is contributed to having strong control over the behavior of the users and providing immediate feedback on errors and misconceptions. Opponents of this approach, on the other hand, have argued that active approach through its interventionist style does not provide users the flexibility needed to observe their own behavior and discover their own errors, hence the users are not given an opportunity to selfdebug their solutions. This paper covers the engineering of intelligent program diagnosis systems and reports an empirical evaluation which attempts to get some insights into the superiority of active approach over passive approach or vice versa. The evaluation is conducted using our prototype system DISCOVER. The system provides a visualization-based environment which supports both active and passive modes of intelligent program diagnosis. 相似文献
162.
Syed Zamberi Ahmad Abdul Rahim Abu Bakar Tengku Mohamed Faziharudean Khairul Anwar Mohamad Zaki 《Information Technology for Development》2013,19(4):555-572
The purpose of this paper is to empirically examine determinants of e-commerce adoption among Malaysian small- and medium-sized enterprises (SMEs). This study tested eight hypotheses on determinants affecting e-commerce adoption with empirical data from several survey instruments: an online questionnaire-based survey, mailed survey and questionnaire collected in-person from a sample of 307 SMEs in Malaysia. The findings show that e-commerce adoption within Malaysian SMEs is affected by perceived relative advantage, perceived compatibility, managers/owner's knowledge and expertise, management characteristics and external change agents. This study contributes to enhancing the understanding of the determinants of adopting e-commerce in SMEs and provides some interesting perspective from Malaysia. Those parties interested in promoting their business online may find these results helpful in guiding their efforts. 相似文献
163.
M. Syed Ali N. Gunasekaran R. Agalya 《International journal of systems science》2013,44(16):3354-3364
This study is concerned with the problem of non fragile synchronisation of mixed delayed neural networks with randomly occurring controller gain fluctuations. By using a novel mathematical approach and considering the neuron activation functions, improved delay-dependent stability results are formulated in terms of linear matrix inequalities (LMIs). An augmented new Lyapunov-Krasovskii functional (LKF) that contains double and triple integral terms is constructed to ensure the asymptotic stability of the error system which guarantees the master system synchronise with the slave system. Finally, numerical examples are provided to show the effectiveness of the proposed theoretical results. 相似文献
164.
Onkar Singh Chauhan U. Syed Abdul Kader Prachi Vaidya Ajay Singh Rajawat Ajai Ratheesh Ramakrishnan 《International journal of remote sensing》2013,34(14):4393-4407
The magnitude of precipitation plays an important role in the yield and supply of terrigenous matter into the sea through fluvial supply. The influence of climate on the influx of total suspended matter (TSM) into the continental margin of the SE Arabian Sea has been evaluated from subweekly synoptic variations in TSM and its advection rates, currents and winds during the southwest monsoon (SWM) and postmonsoon season. Our study endorses the high influx of TSM during the SWM (>82 mg l?1; advection 26–110 mg m?2 s?1), albeit that most of it is sequestered into the shallow coastal region. Over the mid-outer shelf, there is uniformly low TSM (12–24 mg l?1) and a weak TSM advection (9–4 mg m?2 s?1) throughout the year. This trend is persistent also in areas having upwelling-induced high marine productivity. We therefore surmise that higher fluvial influx and primary production during the SWM do not necessarily enhance the supply of particulate matter into the deeper offshore regions of the SE Arabian Sea. We ascribe a vital role to the prevailing morphodynamic processes. 相似文献
165.
Tariq Mahmood Syed Imran Jami Zubair Ahmed Shaikh Muhammad Hussain Mughal 《Computer Standards & Interfaces》2013,35(1):6-29
In this paper, we implement a provenance-aware system for documenting publications, called PADS. It employs a three-layered provenance hierarchy, which can output diverse types of provenance data related to the research life cycle. From this, we generate different profiles for research ventures, reviewers, and authors. PADS employs the standard Open Provenance Model (OPM) specification for capturing provenance data, and stores this data as ontological instances. We show that data is retrieved without any apparent delay in the execution time of the queries. We also demonstrate how this data can be used to make useful recommendations to the organizers, in order to manage upcoming research ventures. 相似文献
166.
NUMERICAL SIMULATION OF AN OSCILLATING FLOW PAST A CIRCULAR CYLINDER IN THE VICINITY OF A PLANE WALL
Oscillating flow around a circular cylinder in the vicinity of a plane wall was investigated by solving the two-dimensional incompressible Navier-Stokes equations with a finite element Galarkin residual method. The effect of the gap G/D between the cylinder surface and the wall on the flow behavior was studied. For the case of G/D 〈 0.25, the periodicity in the flow is attributed to both the outer shear layer instability and the oscillating frequency. As G/D 〉 0.25, vortex shedding occurs and the periodicity in the flow is mainly due to the competition of the oscillating frcqucncy and the vortex shedding frequency from an isolated stationary cylinder. 相似文献
167.
168.
Process modeling in machining. Part II: validation and applications of the determined flow stress data 总被引:1,自引:0,他引:1
Mahmoud Shatla Christian Kerk Taylan Altan 《International Journal of Machine Tools and Manufacture》2001,41(11)
The flow stress data, determined in Part I of the present study, is validated by using it as an input to the finite element method and analytical based computer programs to predict process variables in metal cutting. The predicted process variables in two-dimensional orthogonal turning and three-dimensional face milling operations, are compared with the published experimental data and the results of experiments conducted in the present work. The majority of the predictions have been found to be in reasonable agreement with the measured results. The comparisons have been discussed and, in the case of unsatisfactory agreement, the reasons for inaccurate predictions are reviewed. The flow stress data of AISI H13 tool steel (46 HRC), determined in Part I is used in this study to investigate the influence of edge preparation on forces in the cutting and feed directions, tool stresses and cutting temperatures. It has been concluded that the hone-radius edge with a hone radius of 0.1 mm provides the maximum resistance to chipping and the chamfered edge (20°×0.1 mm) has the minimum flank and crater wears for the conditions used in the present study. 相似文献
169.
O'Neill K. Haider S.A. Geimer S.D. Paulsen K.D. 《Geoscience and Remote Sensing, IEEE Transactions on》2001,39(7):1556-1565
Throughout the world, the problem of buried unexploded ordnance (UXO) poses an enormous, persistent, and expensive problem. While UXO generally consists of sizable bodies of ferrous metal and can therefore be detected, with current technology it is extremely difficult to distinguish them reliably from typically widespread pieces of clutter. Thus the problem is one of subsurface discrimination. The authors previous modeling work on scattering of ground penetrating radar (GPR) from metallic objects surrounded by an infinite soil-like medium has suggested the utility of a number of key discriminants in broadband fully polarimetric sensing. In particular, resonance structure, induced field rotation and ellipticity, and bistatic observation of scattered signals were shown to offer key information about target shape and size. The authors investigate the effects on signature features of the proximity of a ground surface to the target, for the common case of shallow burial (<1 m). Overall, their analyses suggest that the key discriminants seen in scattering in an infinite medium survive the complex interactions with the ground surface. In some instances, these revealing signatures appear to be strengthened by the presence of a nearby surface. Multiposition backscatter also allows fundamental inferences about target elongation and symmetry when those cannot be obtained from single position viewing 相似文献
170.
Bjørn Winther‐Jensen Noel Clark Priya Subramanian Richard Helmer Syed Ashraf Gordon Wallace Leone Spiccia Douglas MacFarlane 《应用聚合物科学杂志》2007,104(6):3938-3947
Conducting polymers such as polypyrrole may be useful in smart packaging products, provided application methods can be developed that circumvent the insolubility and infusibility of these materials. Experiments were conducted in five research areas relevant to the application of polypyrrole to nonrigid substrates. The studies reveal that application of polypyrrole from the liquid phase, either by deposition from depleted bulk solution or inkjet printing dispersions, is unlikely to give films as regular as those produced by vapor phase polymerization. Using the latter approach, two potential methods of applying patterned polypyrrole films to nonrigid substrates were developed. The first used hypochlorite to pattern a continuous film of polypyrrole, previously applied by vapor phase polymerization. The second used inkjet printing to apply an oxidant solution, whose pH had been raised with a volatile base, to nonrigid substrates. The higher pH reduced corrosion of the print head, increasing the lifetime of printers exposed to oxidative compounds. The base was subsequently evaporated by heating, and the dried oxidant used as a template for vapor phase polymerization of polypyrrole. This method gave smooth, shiny and adherent polypyrrole films on papers and polyester transparency, with high resolution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3938–3947, 2007 相似文献