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With the recent rising popularity of music streaming platforms, consumers are now able to enjoy music as a service, playing music for free without paying to obtain the ownership, the threat to the record labels’ financial prospect is eminent. We propose a novel decision support framework to assist the record label in making better informed decisions in the postrelease management timeframe to maximise the expected profit. By identifying the musical product as a durable goods, we model the consumers’ consumption rule with forward-looking behaviour, viewing music streaming as the consumers’ option of delayed consumption, making purchase only when the expected discounted lifetime utility exceeds the expected utility from streaming. Our proposed decision support framework has the record label use both the price and advertising as instrument of control in achieving maximised expected discounted profit, playing strategically in anticipating to the consumers’ decisions using an interactive Markov chain. We show in our illustrative example the proposed decision support framework is able to make decisions dynamically and performs substantially better than other single control variable decision tools.

It is a well recognized understanding that workers whose voice needs to be heard should be actively encouraged as full participants and involved in the early design stages of new ergonomic work system which encompass the development and implementation of new tools, workplaces, technologies or organizations. This paper presents a novel participatory strategy to evaluate three key psychological factors which are respectively mental fatigue, spiritual stress, and emotional satisfaction in work system design based on a modified version of Participatory Ergonomics (PE). In specific, it integrates a PE technique with a formulation view by combining the parallel development of PE strategies, frameworks and functions throughout the coverage of the entire work system design process, so as to bridge the gap between qualitative and quantitative analysis of psychological factors which can cause adverse or advantageous effects on worker's physiological and behavioral performance.

With the Bondi‐Metzner‐Sachs (BMS) group in general relativity as the main motivation and example, a theorem is proved which may be described as follows. Let G be a complex semisimple, connected and simply connected Lie group with compact real form K , and let A be a metrizable, complete and locally convex real topological vector space on which there is a continuous G action. Consider the semidirect product topological group Gx s A (which is, in general, infinite‐dimensional) constructed naturally out of G and A . If the set of equivalence classes of irreducible representations of K in A satisfies certain hypotheses, then the second cohomology group of G x s A in the sense of continuous group cohomology is trivial. When G = SL (2, C ) and A is an appropriate function space of real‐valued functions of the 2‐sphere endowed with a specific G action (e.g. A may consist of C k , k ⩾ 3, real‐valued functions defined on the 2‐sphere), the semidirect product group is the universal cover of the BMS group. The theorem implies the existence of lifting of the projective unitary representations of the BMS group to the linear unitary representations of its universal cover. In the quantum context when we consider massless quantum fields at null infinity of a non‐stationary, asymptotically Minkowskian space‐time, in place of the projective unitary representations of the BMS group, there is no loss of generality in considering the linear unitary representations of its universal cover instead.

The increasing interest in the Semantic Web is producing a growing number of publicly available domain ontologies. These ontologies are a rich source of information that could be very helpful during the process of engineering other domain ontologies. We present an automatic technique that, given a set of Web documents, selects appropriate domain ontologies from a collection of pre-existing ontologies. We empirically compare an ontology match score that is based on statistical techniques with simple keyword matching algorithms. The algorithms were tested on a set of 183 publicly available ontologies and documents representing ten different domains. Our algorithm was able to select the correct domain ontology as the top ranked ontology 8 out of 10 times.

We present a patient with a left atrial hemangioma associated with shortness of breath and irregular heart-beats. Imaging modalities used to evaluate this rare tumor demonstrated characteristic features of its vascular nature. After successful surgical excision of the tumor under cardiopulmonary bypass, there were no clinical or echocardiographic evidence of recurrence at 18 months.

We adopt the concept of using pheromones to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81 (2010) 016113]. The path generation method consists of two stages. In the first stage, a pheromone is dropped to the nodes by packets forwarded according to the global dynamic routing strategy. In the second stage, pheromone static paths are generated according to the pheromone density. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resources than the global dynamic routing strategy.

Previous studies have demonstrated that mitral regurgitation (MR) greatly influenced long-term outcome after surgical mitral commissurotomy in pts with mitral stenosis. However, this issue has not been addressed after balloon mitral valvotomy (BMV). We therefore examined 6 year follow-up (FU) data in 69 pts who presented MR assessed by angiography before BMV (group 1), and compared the results with 75 pts who had no MR (group 2). Mean FU period was 27 ± 20 mo in group 1 and 33 ± 23 mo in group 2 (p = NS). Comparison of pts baseline characteristics, mitral valve area (MVA) before and after BMV and FU results between the groups were: Clinical Profile Group 1 Group 2 p-value Age (yr) 57 ± 13 45 ± 16 0.0001 Sex: M/F 80%/20% 17%/83% NS NYHA-FC: III-IV 90% 81% NS Echo score g8 22% 12% NS Fluoroscopic Ca 2+ 87% 60% 0.001 A.F 56% 19% 0.0001 Pre 2D MVA (cm 2 ) 1.06 ± 0.30 100 ± 027 NS Post 2D MVA (cm 2 ) 1.71 ± 0.35 1.88±0.41 0.01 FU NYHA class I 51% 88% 0.0001 Cardiac events (CE) 28% 9% l 0.01 CE = stroke, repeat BMV, mitral valve replacement (MVR), and death Comparison of 6 year CE-free and MVR-free actuarial survival rates were: Gr 1/Gr 2 1-yr 2-yr 3-yr 4-yr 5-yr 6-yr p-value CE-free (%) 87/94 79/92 73/90 65/90 59/90 49/79 0.002 MVR-free (%) 93/96 89/96 82/96 78/96 78/96 65/84 0.01 Hazard risk ratio by Cox regression analysis was 3.7 (95% CI: 1.5-8.9) times greater for CE (p l 0.01), and 4.0 (1.2–12.7) times greater for MVR (p l 0.05) at FU in group 1 than in group 2. Conclusions (1) MR before BMV increases risk for late CE, particularly requiring MVR in the early FU. (2) Pts with MR appears to be older with calcified valves and AF, and to obtain smaller MVA post BMV, all of which may exacerbate the poor later outcome. (3) Half of such pts may still derive long-term benefits from BMV.