4,649 research outputs found

    A Low Cost Two-Tier Architecture Model For High Availability Clusters Application Load Balancing

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    This article proposes a design and implementation of a low cost two-tier architecture model for high availability cluster combined with load-balancing and shared storage technology to achieve desired scale of three-tier architecture for application load balancing e.g. web servers. The research work proposes a design that physically omits Network File System (NFS) server nodes and implements NFS server functionalities within the cluster nodes, through Red Hat Cluster Suite (RHCS) with High Availability (HA) proxy load balancing technologies. In order to achieve a low-cost implementation in terms of investment in hardware and computing solutions, the proposed architecture will be beneficial. This system intends to provide steady service despite any system components fails due to uncertainly such as network system, storage and applications.Comment: Load balancing, high availability cluster, web server cluster

    Comparative Study on Agile software development methodologies

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    Today-s business environment is very much dynamic, and organisations are constantly changing their software requirements to adjust with new environment. They also demand for fast delivery of software products as well as for accepting changing requirements. In this aspect, traditional plan-driven developments fail to meet up these requirements. Though traditional software development methodologies, such as life cycle-based structured and object oriented approaches, continue to dominate the systems development few decades and much research has done in traditional methodologies, Agile software development brings its own set of novel challenges that must be addressed to satisfy the customer through early and continuous delivery of the valuable software. It is a set of software development methods based on iterative and incremental development process, where requirements and development evolve through collaboration between self-organizing, cross-functional teams that allows rapid delivery of high quality software to meet customer needs and also accommodate changes in the requirements. In this paper, we significantly identify and describe the major factors, that Agile development approach improves software development process to meet the rapid changing business environments. We also provide a brief comparison of agile development methodologies with traditional systems development methodologies, and discuss current state of adopting agile methodologies. We speculate that from the need to satisfy the customer through early and continuous delivery of the valuable software, Agile software development is emerged as an alternative to traditional plan-based software development methods. The purpose of this paper, is to provide an in-depth understanding, the major benefits of agile development approach to software development industry, as well as provide a comparison study report of ASDM over TSDM.Comment: 25 pages, 25 images, 86 references used, with authors biographie

    Consumer engagement with social media platforms: a study of the influence of attitudinal components on cutting edge technology adaptation behaviour

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    Despite pervasive use of digital devices, the influence of simultaneous and combined attitudinal components on consumers’ social media adaptation behaviours remains understudied. This research aims to address this gap in the literature by examining the influence of combined attitudinal components on consumers’ continuous interaction with social media platforms. An online survey was conducted to obtain robust quantitative data on consumers’ interaction and engagement with cutting edge technology such as social media. The findings indicate that consumers’ combined cognitive (perceived opportunity, perceived social influence and perceived control) and affective (enjoyment, self-enhancement, trust and fear) attitudinal components are the antecedents to consumers’ positive and negative adaptation behaviours of social media platforms. Consumers continuously engage with cutting edge social media platforms, either in positive adaptation behaviour (exploration to maximise or exploitation to satisfice social media led benefits) or negative adaptation behaviour (explore to revert from or avoid social media platforms) influenced by combined cognitive and affective attitudinal attributes. The study enriches and advances existing literature by identifying and analysing the influence of both cognitive and affective attitudinal attributes influencing consumers’ positive and negative adaptation behaviours of cutting edge digital technology such as social media platforms. The study helps marketers and IS managers in profiling consumers and understanding consumption patterns while interacting with cutting edge social medial platforms

    Comparative Study on Agile Software Development Methodologies

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    Today2018;s business environment is very much dynamic, and organizations are constantly changing their software requirements to adjust with new environment. They also demand for fast delivery of software products as well as for accepting changing requirements. In this aspect, traditional plan-driven developments fail to meet up these requirements. Though traditional software development methodologies, such as life cycle-based structured and object oriented approaches, continue to dominate the systems development few decades and much research has done in traditional methodologies, Agile software development brings its own set of novel challenges that must be addressed to satisfy the customer through early and continuous delivery of the valuable software. It2018;s a set of software development methods based on iterative and incremental development process, where requirements and development evolve through collaboration between self-organizing, cross-functional teams that allows rapid delivery of high quality software to meet customer needs and also accommodate changes in the requirements. In this paper, we significantly indentify and describe the major factors, that Agile development approach improves software development process to meet the rapid changing business environments. We also provide a brief comparison of agile development methodologies with traditional systems development methodologies, and discuss current state of adopting agile methodologies

    Explicating industrial brand equity: integrating brand trust, brand performance and industrial brand image

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    Purpose (mandatory) The research explores brand equity from multiple perspectives (tangible and intangible) and their joint consequences, namely, on industrial buyers’ brand loyalty and their long-term commitment. The aim is to provide a more comprehensive framework of the buyer’s behavioral response in the business to business context by integrating both trust elements and industrial brand attributes (brand performance and industrial brand image). In addition, the study explores the mediation effects of trust and brand attributes on industrial buyers’ responses such as loyalty and long-term commitment. Design/methodology/approach (mandatory) Using a survey approach, the study includes respondents working in the HVAC industry in Malaysia, and data are collected in the industrial air conditioning segment. The research model was tested with SEM. Findings (mandatory) Findings show that brand performance and industrial brand image directly affect brand trust but with different effects on buyers’ commitment and loyalty. Interestingly, industrial brand image only mediates the responses via brand trust, while brand performance has a direct effect. Thus, both brand performance and industrial brand image build buyer trust. But in this context, it is brand performance rather than industrial brand image that influences long-term commitment and loyalty. The study concludes that in the HVAC industry, brand performance, industrial brand image, buyer trust, industrial loyalty, and commitment build brand equity. Originality/value (mandatory) Significant research reveals that, in business-to-business contexts, brand equity depends on the supplier’s brand trust and attributes of the brand such as brand image and brand performance. While useful in guiding a supplier’s or industry’s brand strategy, the study of both brand trust and brand attributes has led to only a partial explanation of the supplier’s or industry’s brand equity. The present research explores industrial brand equity, focusing on tangible assets (performance) and intangible assets (brand image), and their joint consequences

    Non-parabolicity of the conduction band of wurtzite GaN

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    Using cyclotron resonance, we measure the effective mass, mm*, of electrons in AlGaN/GaN heterostructures with densities, n2D∼1−6×1012n_{2D}\sim 1-6\times10^{12}cm−2^{-2}. From our extensive data, we extrapolate a band edge mass of (0.208±0.002)me(0.208\pm0.002) m_e. By comparing our mm* data with the results of a multi-band \textbf{k.p} calculation we infer that the effect of remote bands is essential in explaining the observed conduction band non-parabolicity (NP). Our calculation of polaron mass corrections -- including finite width and screening - suggests those to be negligible. It implies that the behavior of m∗(n2D)m*(n_{2D}) can be understood solely in terms of NP. Finally, using our NP and polaron corrections, we are able to reduce the large scatter in the published band edge mass values

    Suppression of Higgsino mediated proton decay by cancellations in GUTs and strings

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    A mechanism for the enhancement for proton lifetime in supersymmetric/supergravity (SUSY/SUGRA) grand unified theories (GUTs) and in string theory models is discussed where Higgsino mediated proton decay arising from color triplets (anti-triplets) with charges Q=−1/3(1/3)Q=-1/3(1/3) and Q=−4/3(4/3)Q=-4/3(4/3) is suppressed by an internal cancellation due to contributions from different sources. We exhibit the mechanism for an SU(5) model with 45H+45ˉH45_H+\bar{45}_H Higgs multiplets in addition to the usual Higgs structure of the minimal model. This model contains both Q=−1/3(1/3)Q=-1/3(1/3) and Q=−4/3(4/3)Q=-4/3(4/3) Higgs color triplets (anti-triplets) and simple constraints allow for a complete suppression of Higgsino mediated proton decay. Suppression of proton decay in an SU(5) model with Planck scale contributions is also considered. The suppression mechanism is then exhibited for an SO(10) model with a unified Higgs structure involving 144H+144ˉH144_H+\bar{144}_H representations.The SU(5) decomposition of 144H+144ˉH144_H+\bar{144}_H contains 5H+5ˉH5_H+\bar 5_H and 45H+45ˉH45_H+\bar{45}_H and the cancellation mechanism arises among these contributions which mirrror the SU(5) case. The cancellation mechanism appears to be more generally valid for a larger class of unification models. Specifically the cancellation mechanism may play a role in string model constructions to suppress proton decay from dimension five operators. The mechanism allows for the suppression of proton decay consistent with current data allowing for the possibility that proton decay may be visible in the next round of nucleon stability experiment.Comment: 26 pages, no figures. Revtex 4. To appear in Physical Review
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