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71.
In this paper, we depart from the literature on electricity consumption–real GDP in that for the first time we examine the reaction of real GDP to shocks in electricity consumption. To achieve this goal, we use the structural vector autoregressive (SVAR) model and examine the impact of electricity consumption shocks on real GDP for the G7 countries. We find that except for the USA, electricity consumption has a statistically significant positive impact on real GDP over short horizons. This finding implies that except for the USA, electricity conservation policies will hurt real GDP in the G7 countries.  相似文献   
72.
Wireless Personal Communications - The advancements of technology in the field of communication made WSN based IoT attractive and applicable to various areas. It is comprised IoT nodes that work on...  相似文献   
73.
74.
This paper examines the anticorrosion characteristics of three different benzimidazole derivatives towards mild steel in 0.5?M hydrochloric acid at temperature ranges from 303 to 323?K. The benzimidazole derivatives used for the screening studies are 2-(2-methyl-1H-benzimidazol-1-yl) acethydrazide (EMBAH), 2-(2-ethyl-1H-benzimidazol-1-yl) acethydrazide (EEBAH) and 2-(2-propyl-1H-benzimidazol-1-yl) acethydrazide (EPBAH). The corrosion inhibition was investigated by weight loss, electrochemical impedance spectroscopy and potentiodynamic polarization studies. The adsorption interaction between metal and inhibitor followed Langmuir adsorption isotherm. The Gibb’s free energy values clarify the spontaneous nature of adsorption process. The temperature dependence of inhibition efficiency was explained by considering thermodynamic parameters of adsorption and kinetic parameters of corrosion. These inhibitors showed good efficiency at lower as well as moderately higher temperatures. Quantum chemical calculations were done using DFT at the B3LYP/6-31G1 level to study the electronic properties of the molecules for correlating the inhibitive effect and molecular structure.  相似文献   
75.
Current epileptic seizure "prediction" algorithms are generally based on the knowledge of seizure occurring time and analyze the electroencephalogram (EEG) recordings retrospectively. It is then obvious that, although these analyses provide evidence of brain activity changes prior to epileptic seizures, they cannot be applied to develop implantable devices for diagnostic and therapeutic purposes. In this paper, we describe an adaptive procedure to prospectively analyze continuous, long-term EEG recordings when only the occurring time of the first seizure is known. The algorithm is based on the convergence and divergence of short-term maximum Lyapunov exponents (STLmax) among critical electrode sites selected adaptively. A warning of an impending seizure is then issued. Global optimization techniques are applied for selecting the critical groups of electrode sites. The adaptive seizure prediction algorithm (ASPA) was tested in continuous 0.76 to 5.84 days intracranial EEG recordings from a group of five patients with refractory temporal lobe epilepsy. A fixed parameter setting applied to all cases predicted 82% of seizures with a false prediction rate of 0.16/h. Seizure warnings occurred an average of 71.7 min before ictal onset. Similar results were produced by dividing the available EEG recordings into half training and testing portions. Optimizing the parameters for individual patients improved sensitivity (84% overall) and reduced false prediction rate (0.12/h overall). These results indicate that ASPA can be applied to implantable devices for diagnostic and therapeutic purposes.  相似文献   
76.
The recently developed Li-excess cation-disordered rock salts (DRXs) exhibit an excellent chemical diversity for the development of alternative Co/Ni-free high-energy cathodes. Herein, the synthesis of a highly fluorinated DRX cathode, Li1.2Mn0.6Ti0.2O1.8F0.2, based on cost-effective and earth-abundant transition metals, via a solid-state reaction, is reported. The fluorinated DRX cathode using ammonium fluoride precursor exhibits more uniform particle size and delivers a specific discharge capacity of 233 mAh g−1 and specific energy of 754 Wh kg−1, with 206 mAh g−1 retained after 200 cycles. The combined synchrotron X-ray absorption spectroscopy and resonant inelastic X-ray scattering spectroscopy analysis reveals that the remarkable cycling performance is attributed to the high fluorination and thus enhanced Mn content, enabling the utilization of more Mn redox than the oxide analog. This study demonstrates a great promise to develop next-generation cost-effective DRX cathodes with enhanced capacity retention for high-energy Li-ion batteries.  相似文献   
77.
Overview of multicarrier CDMA   总被引:43,自引:0,他引:43  
The authors present an overview of new multiple access schemes based on a combination of code division and multicarrier techniques, such as multicarrier code-division multiple access (MC-CDMA), multicarrier direct sequence CDMA (multicarrier DS-CDMA), and multitone CDMA (MT-CDMA)  相似文献   
78.
Wireless Personal Communications - The ongoing technological developments have totally transformed the lives of human beings. With the emergence of the smart era and the smart city concept, a few...  相似文献   
79.
Ternary I‐III‐VI2 nanocrystals (NCs), such as CuInS2, are receiving attention as heavy‐metals‐free materials for solar cells, luminescent solar concentrators (LSCs), LEDs, and bio‐imaging. The origin of the optical properties of CuInS2 NCs are however not fully understood. A recent theoretical model suggests that their characteristic Stokes‐shifted and long‐lived luminescence arises from the structure of the valence band (VB) and predicts distinctive optical behaviours in defect‐free NCs: the quadratic dependence of the radiative decay rate and the Stokes shift on the NC radius. If confirmed, this would have crucial implications for LSCs as the solar spectral coverage ensured by low‐bandgap NCs would be accompanied by increased re‐absorption losses. Here, by studying stoichiometric CuInS2 NCs, it is revealed for the first time the spectroscopic signatures predicted for the free band‐edge exciton, thus supporting the VB‐structure model. At very low temperatures, the NCs also show dark‐state emission likely originating from enhanced electron‐hole spin interaction. The impact of the observed optical behaviours on LSCs is evaluated by Monte Carlo ray‐tracing simulations. Based on the emerging device design guidelines, optical‐grade large‐area (30×30 cm2) LSCs with optical power efficiency (OPE) as high as 6.8% are fabricated, corresponding to the highest value reported to date for large‐area devices.  相似文献   
80.
eWALL framework, under development in the European eWALL project (project no. 610658: “eWALL for Active Long Living”) is meant for care of population with age related impairments, mild dementia and COPD. Expanded eWALL (e2WALL) is planned to be an integrated quality framework for long-term care services which will cover very different types of care: all healthcare (both preventive and rehabilitative), societal services, care for cognitive diseases, services delivered at home as well as support for caregivers as an integral part of the quality improvement process. Thus, we present e2WALL home system that would encompass installation (setup) of e2WALL in homes (flats, houses and aging homes) and their management and maintenance across Europe, starting from the partners involved in eWALL (Austria, Bulgaria, Croatia, Denmark, Former Yugoslav Republic of Macedonia, Germany, Greece, Italy, Montenegro, The Netherlands and Romania) and expanding the partnership to the most of Europe (e.g. United Kingdom, Poland, Czech Republic…). This would be a direct application of the developed e2WALL platform and should be done through a network of collaborating small-to-medium sized enterprises (SMEs), each of whom would lead the process of setting up e2WALL system and continuing to provide support services to homes in their respective country. In this way, the growth of high tech and innovative SMEs will be ensured at pan European level, which will enable growth over restricted national market and stimulate European investments in SMEs and startups. Actually, the bigger platform will enable e2WALL European Ecosystem (e4WALL), which can then expand into other non-European markets (e.g. Asia, USA) and means sustainability beyond the life of the project. e2WALL will lead to connected tech start-up hubs to the larger European business ecosystem and will contribute to increased access of country-specific and customized new product to the pan European market, which will lead to increase of employed qualified individuals. Another important focus would be creating an energy efficient environment for a new social network where registered users would provide on-demand services.  相似文献   
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