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With growing adoption of business analytics, it is important for investing firms to understand how business value is created from investments. Studies in IT domain have highlighted how higher investment in technology may not bring more returns, rather how IT as an organizational capability acts as a key mediator in value creation. This research extends the model to business analytics, to identify elements of analytics technology assets and business analytics capability and to understand the mechanism of business value creation using multiple case studies. We capture how analytics resources contribute to business performance by developing operational and organizational performance measures.  相似文献   
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A physical model of split-window and multi-angle algorithms for the retrieval of sea surface temperature has been obtained. It is shown that optical thickness in the thermal infrared window region is approximately represented by a separable function of wavelength and atmospheric variables which greatly simplify the radiative transfer model. In modelling the temperature retrieval algorithms we exploit the correlation that exists between the sea surface temperature and the average temperature of the atmosphere. It is shown that, to the extent this correlation is maintained, there is a simple relationship between surface temperature and the brightness temperatures measured in two split-window or multi-angle channels. The different atmospheric conditions which cause spread in this relationship are briefly discussed. It is shown that measurements at three optical thicknesses instead of two as in the case of the split-window method improve the SST retrieval accuracy since it can take care of non-equilibrium conditions such as inversions, surface instabilities, etc., prevailing in the atmosphere.  相似文献   
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Density functional calculations and minimization techniques have been employed to characterize the structural and electronic properties of [5,6]-heterofullerene-C58Si-C2v. Since it has odd number of atoms and a near planar tetracoordinate Si atom on the skeleton of the cage, it has odd number of atoms assembling a cage and is a novel molecule. Vibrational frequencies of the molecule have been calculated at the B3LYP/6-31G* level of theory. The absence of imaginary vibrational frequency confirms that the molecule corresponds to a true minimum on the potential energy hypersurface. Sixteen 13C nuclear magnetic resonance (NMR) spectral signals of C58Si are characterized, and its heat of formation was estimated in this work.  相似文献   
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In Internet-based commerce, sellers often use multiple distribution channels for the sale of standard consumer goods. We study a model of second-degree price discrimination in which a monopolist sells to risk-averse buyers. The seller uses two channels that differ in their risk attributes. In one channel prices and qualities are fixed and availability is assured. In the second channel, the seller offers a joint distribution of prices and qualities and may not guarantee availability. We characterize optimal two-channel selling policies. We show that it can be optimal to offer multiple identical items in a random sale event. However, the seller cannot benefit by offering two distinct quality levels in a sale event that is held with probability smaller than one. We use the model to offer explanations for the observed behavior of online sellers and discuss implementation issues in recent e-commerce environments.  相似文献   
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Consider sets S of hypercubes of side 2 in the discrete n-dimensional torus of side 4 with the property that every possible hypercube of side 2 has a nonempty intersection with some hypercube in S. The problem of minimizing the size of S is studied in two settings, depending on whether intersections between hypercubes in S are allowed or not. If intersections are not allowed, then one is asking for the smallest size of a non-extensible packing S  ; this size is denoted by f(n)f(n). If intersections are allowed, then the structure S is called a blocking set. The smallest size of a blocking set S   is denoted by h(n)h(n). By computer-aided techniques, it is shown that f(5)=12f(5)=12, f(6)=16f(6)=16, h(6)=15h(6)=15 and h(7)≤23h(7)23. Also, non-extensible packings as well as blocking sets of certain small sizes are classified for n≤6n6. There is a direct connection between these problems and a covering problem originating from the football pools.  相似文献   
139.
Some of the classical connectivity concepts in Graph theory are generalized in this article. Strong and strongest strong cycles are introduced. Partial blocks are characterized using strongest paths. Some necessary and sufficient conditions for a weighted graph to be a partial block are also presented.  相似文献   
140.
Tensile flow behaviour of P9 steel with different silicon content has been examined in the framework of Hollomon, Ludwik, Swift, Ludwigson and Voce relationships for a wide temperature range (300–873 K) at a strain rate of 1.3 × 10?3 s?1. Ludwigson equation described true stress (σ)–true plastic strain (ε) data most accurately in the range 300–723 K. At high temperatures (773–873 K), Ludwigson equation reduces to Hollomon equation. The variations of instantaneous work hardening rate (θ = /) and θσ with stress indicated two-stage work hardening behaviour. True stress–true plastic strain, flow parameters, θ vs. σ and θσ vs. σ with respect to temperature exhibited three distinct temperature regimes and displayed anomalous behaviour due to dynamic strain ageing at intermediate temperatures. Rapid decrease in flow stress and flow parameters, and rapid shift in θσ and θσσ towards lower stresses with increase in temperature indicated dominance of dynamic recovery at high temperatures.  相似文献   
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