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A hybrid spectral/boundary element approach is proposed to examine the influence of Couette channel flow on transient coating of highly elastic fluids. The viscoelastic instability of one‐dimensional plane Couette flow is first determined for a large class of Oldroyd fluids with added viscosity, which typically represent polymer solutions composed of a Newtonian solvent and a polymeric solute. The Johnson‐Segalman equation is used as the constitutive model. The velocity profile inside the channel is taken as the exit profile for the emerging free‐surface flow. The flow is assumed to be Newtonian as it emerges from the channel. An estimate of the magnitude of the rate‐of‐strain tensor components in the free‐surface region reveals that they are generally smaller than the shear rate inside the channel. The evolution of the flow front is simulated using the boundary element method. For the channel flow, the problem is reduced to a non‐linear dynamical system using the Galerkin projection method. Stability analysis indicates that the channel velocity may be linear or non‐linear depending on the range of the Weissenberg number. The evolution of the coating flow at the exit is examined for steady as well as transient (monotonic and oscillatory) channel flow. It is found that adverse flow can exist as a result of fluid elasticity, which can hinder the process of blade coating.

This paper proposes an effective way to improve poor performance of ISF. The result finding was based on a questionnaire survey, and the selected respondents were asked to evaluate the adoption level of the TQM concept in governing their information systems function. Through the tests of reliability and validity, the proposed instrument was verified as a good measuring tool. The findings show that dissatisfying performers of ISF should pay more emphasis on the practices of user focus, IS top management support, and IS product/service design.

The problem of optimal software reliability design is considered. Allocation models are usually used to compute the target reliability for each module of a software system to maximize the overall system reliability. This objective can also be achieved by employing redundancy, e.g. N‐version programming technique (NVP). A method bridging the allocation model and redundancy approach is derived. The proposed model simultaneously determines both the optimal amount of redundancy and target reliability for each module to achieve the best reliability while the total cost stays within the budget.

The purpose of this study is to understand how IT capabilities for knowledge management and process integration can build a firm's agile process capabilities for sensing, strategic decision and responding. The study also investigates how the three agile capabilities affect firm performance in different competitive environments.

This study conducted a large-scale field survey with firms in the United States. Survey invitations were sent to business executives of the target firms. A total of 254 complete samples were collected for our hypotheses test.

The results confirm the overall significant roles of IT capabilities in the three agile capabilities. The results further reveal that the IT capability for knowledge management has a higher influence on sensing capability, while the IT capability for process integration has a higher influence on responding capability. Moreover, strategic decision and responding capabilities are more important in the high market competition. However, in the low market competition, sensing capability becomes more important while responding capability demonstrates a negative impact on firm performance.

This study helps both academics and practitioners better understand a firm's IT-agility-performance mechanism. Particularly, our findings guide how to achieve agile capabilities and what to focus on under the different levels of market competition.

The purpose of this paper is to apply the boundary element method (BEM) to Stokes flow between eccentric rotating cylinders, considering the case when viscous dissipation plays a significant role and determining the Nusselt number as a function of cylinder geometry parameters.

The problem is described by the equation of motion of Stokes flow and an energy equation with a viscous dissipation term. First, the velocity field and the viscous dissipation term were determined from the momentum equation. The determined dissipation of energy and the constant temperature on the cylinder walls are the conditions for the energy equation, from which the temperature distribution and the heat flux at the boundary of the cylinders are determined. Numerical calculations were performed using the author’s own computer program based on BEM. Verification of the model was carried out by comparing the temperature determined by the BEM with the known theoretical solution for the temperature distribution between two rotating concentric cylinders.

As the ratio of the inner cylinder diameter to the outer cylinder diameter (r1/r2) increases, the Nusselt number increases. The angle of inclination of the function of the Nusselt number versus r1/r2 increases as the distance between the centers of the inner and outer cylinders increases.

The computational results may be used for the design of slide bearings and viscometers for viscosity testing of liquids with high viscosity where viscous dissipation is important. In the work, new integral kernels were determined for BEM needed to determine the viscous dissipation component.

The purpose of this paper is to provide a mathematical framework to optimally allocate resources required for the discovery of vulnerabilities pertaining to different severity risk levels.

Different sets of optimization problems have been formulated and using the concept of dynamic programming approach, sequence of recursive functions has been constructed for the optimal allocation of resources used for discovering vulnerabilities of different severity scores. Mozilla Thunderbird web browser data set has been considered for giving the empirical evaluation by working with vulnerabilities of different severities.

As per the impact associated with a vulnerability, critical and high severity level are required to be patched promptly, and hence, a larger amount of funds have to be allocated for vulnerability discovery. Nevertheless, a low or medium risk vulnerability might also get exploited and thereby their discovery is also crucial for higher severity vulnerabilities. The current framework provides a diversified allocation of funds as per the requirement of a software manager and also aims at improving the discovery of vulnerability significantly.

The finding of this research may enable software managers to adequately assign resources in managing the discovery of vulnerabilities. It may also help in acknowledging the funds required for various bug bounty programs to cater security reporters based on the potential number of vulnerabilities present in software.

Much of the attention has been focused on the vulnerability discovery modeling and the risk associated with the security flaws. But, as far as the authors’ knowledge is concern, there is no such study that incorporates optimal allocation of resources with respect to the vulnerabilities of different severity scores. Hence, the building block of this paper contributes to future research.

Nowadays, the most important challenge in mechanical engineering, power engineering and electronics is a development of effective cooling systems for heat-generating units. Taking into account this challenge, this study aims to deal with computational investigation of thermogravitational energy transport of pseudoplastic nanoliquid in an electronic chamber with a periodic thermally producing unit placed on the bottom heat-conducting wall of finite thickness under an influence of isothermal cooling from vertical side walls.

The control equations formulated using the Boussinesq approach, Ostwald–de Waele power law and single-phase nanofluid model with experimentally based correlations of Guo et al. for nanofluid dynamic viscosity and Jang and Choi for nanofluid thermal conductivity have been worked out by the in-house computational procedure using the finite difference technique. The impact of the Rayleigh number, nanoadditives concentration, frequency of the periodic heat generation from the local element and thickness of the bottom solid substrate on nanoliquid circulation and energy transport has been studied.

It has been found that a raise of the nanoadditives concentration intensifies the cooling of the heat-generating element, while a growth of the heat-generation frequency allows reducing the amplitude of the heater temperature.

Mathematical modeling of a pseudoplastic nanomaterial thermogravitational energy transport in an electronic cabinet with a periodic thermally generating unit, a heat-conducting substrate and isothermal cooling vertical surfaces to identify the possibility of intensifying heat removal from a heated surface.

Although acknowledged as a principal dimension in the context of text mining, time has yet to be formally incorporated into the process of visually representing the relationships between keywords in a knowledge domain. This paper aims to develop and validate the feasibility of adding temporal knowledge to a concept map via pair-wise temporal analysis (PTA).

The paper presents a temporal trend detection algorithm – vector space model – designed to use objective quantitative pair-wise temporal operators to automatically detect co-occurring hot concepts. This PTA approach is demonstrated and validated without loss of generality for a spectrum of information technologies.

The rigorous validation study shows that the resulting temporal assessments are highly correlated with subjective assessments of experts (n = 136), exhibiting substantial reliability-of-agreement measures and average predictive validity above 85 per cent.

Using massive amounts of textual documents available on the Web to first generate a concept map and then add temporal knowledge, the contribution of this work is emphasized and magnified against the current growing attention to big data analytics.

This paper proposes a novel knowledge discovery method to improve a text-based concept map (i.e. semantic graph) via detection and representation of temporal relationships. The originality and value of the proposed method is highlighted in comparison to other knowledge discovery methods.

States that a major problem in dealing with information‐systems reliability is the design of a metric that combines the customer’s needs and preferences with the technical specifications and modular reliability of information systems. Develops one such metric, combining the customer’s requirements and utility with the technical structure of the system. The result is a single metric that can be used for tracking the performance of an information system and as an early signal of the system’s persistent malfunction and low quality of service. This metric can also contribute to the continuous improvement of system reliability by identifying the components whose improved reliability could make the most significant contribution to the overall reliability of the system.

This paper aims to investigate the impact of three different flow channel cross sections on the performance of the fuel cell.

A comprehensive three-dimensional polymer electrolyte membrane fuel cell model has been developed, and a set of conservation equations has been solved. The flow is assumed to be steady, fully developed, laminar and isothermal. The investigated cross sections are the commonly used square cross section, the increasingly used trapezoidal cross section and a novel hybrid configuration where the cross section is square at the inlet and trapezoidal at the outlet.

The results show that a slight gain is obtained when using the hybrid configuration and this is because of increased velocity, which improves the supply of the reactant gases to the catalyst layers (CLs) and removes heat and excess water more effectively compared to other configurations. Further, the reduction of the outlet height of the hybrid configuration leads to even better fuel cell performance and this is again because of increased velocity in the flow channel.

The data generated in this study will be highly valuable to engineers interested in studying the effect of fluid cross -sectional shape on fuel cell performance.

This study proposes a novel flow field with a variable cross section. This design can supply a higher amount of reactant gases to the CLs, dissipates heat and remove excess water more effectively.