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71.
The European Commission-DG JRC has an ongoing research activity on assessing the electricity end uses and energy saving potential, with particular attention to the residential sector. Better equipment efficiency is one of the fastest and most cost-effective responses to limiting growing demand for electricity and at the same time to reduce CO2 emissions [1]. 相似文献
72.
Riedel Silvia Gabrys Bogdan 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(12):1753-1766
In this paper, we provide a theoretical analysis of effects of applying different forecast diversification methods on the structure of the forecast error covariance matrices and decomposed forecast error components based on the bias-variance-Bayes error decomposition of James and Hastie. We express the "diversity” of different forecasts in relation to different error components and propose a measure in order to quantify it. We illustrate and discuss typical inhomogeneities frequently occurring in the forecast error covariance matrices and show that previously proposed pooling based only on error variances cannot fully exploit the complementary information present in a set of diverse forecasts to be combined. If covariance values could be reliably calculated, they could be taken into account during the pooling process. We study the difficult case in which covariance information cannot be measured properly and propose a novel simplified representation of the covariance matrix, which is only based on knowledge about the forecast generation process. Finally, we propose a new pooling approach that avoids inhomogeneities in the forecast error covariance matrix by considering the information contained in the simplified covariance representation and compare it with the error-variance-based pooling approach introduced by Aiolfi and Timmermann. Applying our approach more than once leads to the generation of multistep and multilevel forecast combination structures, which have generated significantly improved forecasts in our previous extensive experimental work; the summary of which is also provided. 相似文献
73.
The suppression of CH4 and CH3OH premixed flames with CBrF3 and CF3I is examined, using computational techniques. By combining sensitivity analysis, reaction pathway analysis (based on carbon,
hydrogen, bromine and iodine atom fluxes) and heat release estimation, we develop an explanation for the difference of suppression
efficiencies which is qualitatively consistent with experimental cup burner data. The key reaction steps and channels responsible
for the (apparent) higher inhibition efficiency of CF3I compared to CBrF3 in CH3OH premixed flames are disclosed, by combining reaction pathway and heat release contribution analysis. The reaction of bromine
atom dominates the decomposition channel for CH3OH but plays a relatively minor role in the activation of CH4, while I atom plays a minor role in CH3OH or CH4 activation. Accordingly, the rate of production of flame propagating radicals CH2O and OH is higher in a CH3OH–air–CBrF3 system than in a CH3OH–air–CF3I system. The overall conclusion is that CBrF3 contributes significantly to flame propagation for CH3OH fuel reactions and consequently more CBrF3 is required to extinguish a CH3OH flame than CF3I. Finally the explanation is validated by applying the reaction “switching-off” test. 相似文献
74.
Inclusion of flaxseed in turkey diets decreases the n‐6/n‐3 PUFA ratio and increases the proportion of biologically active EPA and DHA without affecting meat quality
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75.
This article presents investigations related to the turning of stainless steel as a representative of difficult-to-cut materials and the effectiveness of selected chip breakers working in the local machining environment. Martensitic steel AISI 416 was used to test two commercially available types of chip breaker. The efficiency of a chip breaker working in the range of cutting conditions recommended (by the tool manufacturers) was the aim of the turning tests. As a result of the investigations an algorithm of cutting condition selection, combining both the cutting tests and the simulation procedure for the efficiency of the chip breaker was created. The vision system, equipped with a high-speed camera was used for chip form estimation. Simultaneously, the cutting force components were measured to check if the simulation calculation was correct. The FEM simulation was applied to estimate the manner in which the chip groove was filled. The article presents certain recommendations for cutting condition correction in the local machining environment for the purpose of achieving an acceptable chip form. 相似文献
76.
The equation of calculation of the norms of consumption of vitamins by athletes of different specialization is suggested. Physiological norms of consumption of vitamins by athletes of different specializations depend on the training loads that determine the amount of protein in their nutrition ration. Daily demand of the athlete in a definite vitamin is equal to the physiological norm of the demand in this vitamin of an adult person (not an athlete), multiplied by the quotient of a protein quota of the athletes' ration and physiological demand of the adult person in proteins. Application of the suggested equation allows developing balanced vitamin complexes for ath letes of various specializations. 相似文献
77.
78.
This paper focuses on the development of an optimized photovoltaic tracking system involving low-cost, relative simple mechanisms, with linear actuators able to insure strokes comparable with those resulted when using gear rotary actuators. Starting with a rhombus linkage, with a linear actuator on the diagonal used for the elevation motion till 90°, a new performance solution is generated. This new linkage allows large angular strokes by using an asymmetric rhombus and an eccentrically positioned linear ac... 相似文献
79.
Mutual mobile membrane systems represent a variant of mobile membrane systems in which endocytosis and exocytosis work whenever the involved membranes ??agree?? on the movement by using mutual complement objects placed in membranes. We provide a semi-uniform polynomial solution for a weak NP-complete problem (namely partition problem) by means of mutual mobile membrane systems. 相似文献
80.
Wojciech Zębala Bogdan Słodki 《The International Journal of Advanced Manufacturing Technology》2013,65(5-8):881-893
The paper presents research work concerning difficult-to-cut materials turning and chipbreakers reliability in local operating features. Inconel 718 alloy was used as a sample material and two different chipbreakers were tested. The aim of the research was to check the efficiency of chipbreakers in the area of applications recommended by tool manufacturers. As a result, the algorithm for cutting data selection and correction which combines experiments and simulation processes concerning chip breakage effectiveness was built. To estimate chip forms in tests, the visual system equipped with a high-speed camera was used. The cutting forces measuring system provided information for verification of simulation results. The simulation based on the FEM was applied to estimate chip groove filling. Distributions of temperature and stresses on the tool rake face in the function of distance from the cutting edge were calculated. The paper gives recommendations for cutting data correction to achieve acceptable chip forms. 相似文献