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Catalysis Letters - Industrial Cu/ZnO/Al2O3 or novel rate catalysts, prepared with a photochemical deposition method, were studied under functional CH3OH synthesis conditions at the set temperature...  相似文献   
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Multi-disciplinary software interoperability in the Architecture, Engineering, Construction and Operations industry is becoming a new and widely adopted business culture. Technical advances in interoperability architectures, frameworks, methods and standards during the last decade resulted in higher maturity of product and process models. Mature models, in effect, enable data exchange by an increasing number of software applications in the industry. This establishes trust in data exchange and results in the lower cost impact of inefficient interoperability. The negative cost impact increases with advancing life-cycle phase, from planning and design phase to construction phase and to operation and maintenance phase. Interoperability in the planning and design phase is most mature and well published, while interoperability in the construction phase and for automated manufacturing is less researched. This paper reviews state-of-the art automated manufacturing systems in construction and researches interoperability requirements for automated construction in context of the entire building lifecycle. Our research is based on experimental free-form clay building, designed with embedded simple HVAC components, and manufactured with additive layer technology. Conclusions provide valuable results for interoperability research and practice in construction projects with automated manufacturing systems in place.  相似文献   
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Structural optimization based on the shakedown theory is a powerful and promising technique. However, due to the nonlinearities of physical materials and the number of variable loads in real structures, it is computationally complex and time-consuming. To simplify the occurring non-linear, non-convex optimization problems, the paper suggests reducing the number of yield conditions. The so-called a yield criterion of the mean (integral yield condition) is analysed and explained in detail, which allows taking into account one yield condition for the entire finite element instead of multiple point-wise conditions. This approach shows promising results in numerical application to the optimization of a circular plate, considering a possibility of employing the yield criteria of the mean or pointwise yield conditions in different areas of the plate in particular. The methods applied are based on the assumptions of perfect plasticity and small deformations.  相似文献   
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Previous research has shown loneliness as a threat for the quality of life of older people; therefore the goal of the intervention in a quasi-experimental study was to evaluate and discuss the self-reported level of loneliness of older people in Finland and Slovenia before and after a computer intervention. Intervention in a quasi-experimental study was conducted among 58 older participants at the baseline (M = 72.4 years) and 45 older participants at the follow-up research study (M = 72.9 years). Inferential statistics showed a significant difference in the reduction of loneliness between the countries, and a decreased level of loneliness of older people after completing the computer training course. Although older people experience many age-related problems which may reduce their interest in learning information and communication technology (ICT) skills, it is important that they are computer-proficient, because computer engagement can reduce the level of loneliness of older people and in this way has a positive effect on their quality of life.  相似文献   
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River courses play a vital role in preserving unpolluted ecosystems. On the other hand, networks of sensor nodes can be used to measure characteristic parameters in the environment such as temperature, pressure, humidity or the concentration of pollutants. In the framework of the EU FP7 project “GOLDFISH”, technical competences of a consortium of 11 institutions are hence employed in designing, manufacturing, validating and operating wireless sensors nodes for tracking pollution in remote rivers. The sensor network is composed of sensor clusters located underwater and gateways on the riverbank with long-distance communication links to the central management and monitoring station. Each sensor node is composed of active electronic devices that have to be constantly powered. Batteries can generally be used for this purpose, but problems may occur when they are to be recharged or replaced, especially in the case of large networks placed in scarcely accessible locations. State-of-the-art energy harvesting technologies can hence constitute a viable powering solution. The possibility to use different small-scale river flow energy harvesting principles is thoroughly studied in this work by the University of Rijeka GOLDFISH team: a miniaturized hydro-generator, a ‘piezoelectric eel’ and a hybrid solution of a rotating shaft plucking a piezoelectric beam. The first two concepts are validated experimentally in a flow channel and in real river conditions. The miniaturized hydro-generator with suitable power management electronics is finally embedded into the wireless sensor node deployed into the river, allowing the GSM transmission of collected data to be successfully performed.  相似文献   
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Temporal content variations of approximately 70 C4–C24 fatty acids (FA) in colostrum and milk of ewes consuming winter diet were determined by gas chromatography. The content of monounsaturated, polyunsaturated and straight-chain saturated FA 14:0–16:0 in colostrum was higher whereas the content of 4:0–12:0, 18:0 and branched-chain saturated FA 15:0–17:0 was lower than that in mature milk. The effect of ewe breed on the FA profiles was not significant. The composition of FA changed most significantly 1–2 days after lambing in agreement with the time schedule of colostrum formation. Nevertheless, the content of FA further successively changed up to approximately the 6th day of lactation, whereas further changes up to the 60th day of lactation were smaller. This is consistent with the recommendation that ewes' milk is suitable for human consumption after six-to-eight days of lactation. The higher contents of palmitic and myristic acids in colostrum compared with mature milk suggest that FA composition in colostrum matches the changing needs of the growing lambs.  相似文献   
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Peroxides react with polymers in a variety of ways. The fundamental comprehension and prediction of pertinent kinetics of reactions is consequently indispensable. Based on the mechanisms of reactions of cross-linking process, a new theoretical kinetic model framework was developed. The kinetic model was then applied to the reactions of cross-linking process of various peroxides and a chosen complex polymer compound, namely partially hydrogenated poly(acrylonitrile-co-1,3-butadiene). Whereas the initial macromolecular backbone structure was determined utilizing attached proton test carbon nuclear magnetic resonance, the evolution of overall concentration of cross-links was monitored through viscoelastic characteristics of the system. The model demonstrated good agreement with experimentally measured data and, moreover; the evolution of concentrations of various crucial species inherent to the cross-linking process were predicted. The most significant advantage of the developed kinetic model is that it may be readily applied to an assortment of polymer/peroxide systems.  相似文献   
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The paper presents a general methodology of adaptive control based on fuzzy model to deal with unknown plants. The problem of parameter estimation is solved using a direct approach, i.e. the controller parameters are adapted without explicitly estimating plant parameters. Thus, very simple adaptive and control laws are obtained using Lyapunov stability criterion. The generality of the approach is substantiated by Stone-Weierstrass theorem, which indicates that any continuous function can be approximated by fuzzy basis function expansion. In the sense of adaptive control, this implies the adaptive law with fuzzified adaptive control parameters. The proposed control algorithm may be viewed as an extension of classical adaptive control for linear plants, but compared to the latter it provides higher adaptation ability and consequently better performance if the plant is nonlinear. The global stability of the control system is assured and the tracking error converges to the residual set that depends on fuzzification properties. The main advantage of the approach is simplicity that suits control engineers since wide range of industrial processes can be controlled by the proposed method. In the paper, the control of heat exchanger is performed.  相似文献   
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