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Accurate prediction of the large-scale channel fading is fundamental to planning and optimization in 5G millimeter-wave cellular networks. The current prediction methods, which are either too computationally expensive or inaccurate, are unsuitable for city-scale cell planning and optimization. This paper presents FadeNet, a convolutional neural-network enabled alternative for predicting large-scale fading with high computation speed and accuracy. By using carefully designed input features and neural-network architecture to capture topographical information, FadeNet accurately predicts the large-scale fading from a base station to each location in its coverage area. Evaluations on realistic data, derived from millimeter-wave cells across multiple cities, suggest that FadeNet can achieve a prediction accuracy of 5.6 decibels in root mean square error. In addition, by leveraging the parallel processing capabilities of a graphics processing unit, FadeNet can reduce the prediction time by $40X-1000X$ in comparison to industry prevalent methods like ray-tracing. Generalizations of FadeNet, that can handle variable topographies and base station heights, and its use for optimal cell site selection are also explored.

The energy crisis and the rise of flexible electronics call for a renewable and flexible energy source due to the inconvenience of the traditional power supply. A triboelectric nanogenerator (TENG)...

Purpose The aim of this study was to explore the effects of an enteral nutrition (EN) feeding protocol in critically ill patients. Methods This was a prospective multi-center before-after study. We compared energy related and prognostic indicators between the control group (pre-implementation stage) and intervention group (post-implementation stage). The primary endpoint was the percentage of patients receiving EN within 7 days after ICU admission. Results 209 patients in the control group and 230 patients in the intervention group were enrolled. The implementation of the EN protocol increased the percentage of target energy reached from day 3 to day 7, and the difference between two groups reached statistical significance in day 6 (P = .01) and day 7 (P = .002). But it had no effects on proportion of patient receiving EN (P = .65) and start time of EN (P = .90). The protocol application might be associated with better hospital survival (89.1% vs 82.8%, P = .055) and reduce the incidence of EN related adverse (P = .004). There was no difference in ICU length of stay, duration of mechanical ventilation and ICU cost. Conclusion The implementation of the enteral feeding protocol is associated with improved energy intake and a decreased incidence of enteral nutrition related adverse events for critically ill patients, but it had no statistically beneficial effects on reducing the hospital mortality rate. Trial registration ClinicalTrials.gov , NCT02976155 . Registered November 29, 2016- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02976155 .

Micro-supercapacitors are promising energy storage devices that can complement or even replace lithium-ion batteries in wearable and stretchable microelectronics. However, they often possess a relatively low energy density and limited mechanical stretchability. Here, we report an all-in-one planar micro-supercapacitor arrays (MSCAs) based on hybrid electrodes with ultrathin ZnP nanosheets anchored on 3D laser-induced graphene foams (ZnP@LIG) arranged in island-bridge device architecture. The hybrid electrodes with a large specific surface area demonstrate excellent ionic and electrical conductivities, impressive gravimetric (areal) capacitance of 1425 F g−1 (7.125 F cm−2) at 1 A g−1, and long-term stability. In addition to high energy (245 m Wh cm−2) and power (12.50 mW kg−1 at 145 m Wh cm−2) densities, the MSCAs with excellent cycling stability also showcase adjustable voltage and current outputs through serial and parallel connections of MSC cells in the island-bridge design, which also allows the system to be reversibly stretched up to 100%. Meanwhile, theoretical calculations validated by UV–vis absorption spectra partially suggest that the enhanced capacitance and rate capability may result from the improved electrical conductivity and number of adsorbed charged ions (Na+ in Na2SO4 aqueous electrolyte and K+ in PVA/KCl gel electrolyte) on the pseudocapacitive non-layered ultrathin ZnP nanosheets. The integration of the all-in-one stretchable MSCAs with a crumpled Au-based triboelectric nanogenerator and stretchable crumpled graphene-based strain sensor demonstrates a self-powered stretchable system. The coupled design principle of electronic materials and device architecture provides a promising method to develop high-performance wearable/stretchable energy storage devices and self-powered stretchable systems for future bio-integrated electronics.

Semiconductor heterostructures have emerged as highly promising candidates for energy storage and conversion owing to their tunable electronic and structural properties by rational design and controllable synthesis at a molecular level. The overall electrochemical performance of the semiconductor heterostructures often depends on the carrier mobility from the semiconductor interfaces and faradaic redox reactions from their active sites. Herein, we report a facile, low-cost, two-step method to controllably grow MnO2 nanorods directly on CoMn2O4 nanosheets (i.e., MnO2@CoMn2O4) with robust adhesion. An induced electric field resulted from the interface effect of heterostructures tailors the kinetic performance of electrons and ions during the charge-discharge process, enhancing the electron mobility and reducing diffusion barrier for charge carriers (OH−) ions migration. As a result, the rational design and controllable heterostructures exhibit significantly improved electrochemical capacitive performance, including remarkable specific capacitance, excellent rate capability, and cycling stability. Furthermore, exploring MnO2@CoMn2O4 as positive electrode and N-doping 3D reduction of graphene oxide (N-3DrGO) as negative electrode yields an asymmetric supercapacitor with high energy density (230.57 mWh cm−2), remarkable power density (3.91 mW cm−2 at 149.99 mWh cm−2), and excellent cycling stability (81.3% capacitance retention after 5000 cycles at 3 mA cm−2). This work offers new opportunities to explore high-performance electrode materials by providing methods to control the interface in nano-heterostructures.

We consider linear regression problems for which the underlying model undergoes multiple changes. Our goal is to estimate the number and locations of change-points that segment available data into different regions, and further produce sparse and interpretable models for each region. To address challenges of the existing approaches and to produce interpretable models, we propose a sparse group Lasso based approach for linear regression problems with change-points. Under certain mild assumptions and a properly chosen regularization term, we prove that the solution of the proposed approach is asymptotically consistent. In particular, we show that the estimation error of linear coefficients diminishes, and the locations of the estimated change-points are close to those of true change-points. We further propose a method to choose the regularization term so that the results mentioned above hold. In addition, we show that the complexity of the proposed algorithm is much smaller than those of existing approaches. Numerical examples are provided to validate the analytical results.

Uncoordinated frequency hopping (UFH) has recently emerged as an effective mechanism to defend against jamming attacks. Existing research focuses on the optimal design of the hopping pattern, which implicitly assumes that the strategy of the attacker is fixed. In practice, the attacker might adjust its strategy to maximize its damage on the communication system. In this paper, we study the design of optimal hopping pattern (the defense strategy) as long as the optimal jamming pattern (the attack strategy). In particular, we model the dynamic between the legitimate users and the attacker as a zero sum game, and study the property of this game. We show that when the legitimate users and the jammer can access only one channel at any time, the game has a unique Nash equilibrium. In the Nash equilibrium, the legitimate users and Eve will access or jam only a subset of channels that have good channel quality. Furthermore, the better the channel, the larger the probability that Eve will jam the channel and the smaller the probability the legitimate users will access this channel. We further extend the study to multiple access multiple jamming case and characterize the Nash equilibrium. We also give numerical results to illustrate the analytical results derived in this paper.

Technical plan for the construction of Wind power Station on Housetop of buildings in a City(WSHC in short) put forward in this paper. The wind force turbine with two wind wheels was adopted in WSHC to capture wind energy and produce electricity as much as possible in the limited area on the housetop. No vanes can go down out of WSHC even if an accident of a vane breaking occurs because two technology protection measures are used here: first, the vanes of a wind wheel are linked up by a thin wire rope at middle of them; second, the webs made of stainless steel wires are fixed at inlet and outlet of the accelerate and orientate device. WSHC belong to environmental friendly and animal harmoniously ones because of the consideration of the webs mentioned above, so that the birds are stopped out of the wind power generator. The grid connection mode of commutating, inversing and connecting to the distribution network of the building was adopted in WSHC. Equipped by a connecting device in-house, each wind power generator can be controlled in max electric production mode during the term when voltage output of the generator higher than 12volts. The diameter of accelerate and orientate device of 3.6m was selected on the consideration about structural-load-carrying capacity of the present building. WSHC can be put into commercial operation in most area of China. Some has evident investment effectiveness because the investment payback time is only 2.4years as wind energy density is 300 W/m 2 , annual generation hours are 6000 hours and electricity price is 0.84yuan/(kW·h).

The design for the large scale wind power generator of 40MW, named as Linear Wind power Generator, LWG in short, was put forward. The vanes of LWG run along two of linear steel rails vertically from near the ground up to the high altitude, so that each part of the vanes can run in higher speed and produce mechanical power, the wind energy both near the ground and in high altitude can be utilized, and air kinetic energy will be converted to mechanical energy twice as the vanes run up and down; a special mechanical power transmission makes the mechanical power produced by the yawing wind force turbines transmitted into the inner of steel tower. About 12.3times more of output power can be produced by LWG than present wind power generator equipped with the vanes of same length as LWG.

To make the best of wind energy resources on the earth surface, the plan for a new type of wind power device, named Multiple wind wheel Wind power Device, MWD in short, was put forward. MWD composes steel tower, trusses, generator, long axis, wind turbines and wheel boxes. Only one generator installed on the ground in the middle of the generator room vertically. Several wind turbines installed to the steel tower of MWD, each wind turbine consists of front wind wheel, back wind wheel and wheel box. Common yawing equipment used for the wind turbine at top of the steel tower. Installed with bearings to the steel tower of MWD, driven by a common yawing equipment, each truss can turn slowly and independently around the steel tower as the wind changes its direction. The mechanical power generated by the wind turbines at ends of the trusses is continuously transmitted to the central axis in the middle of the steel tower via a special transmission. It is for the special design of MWD that the wind energy in both the high air and low air can be utilized, the wind energy escaping from back of front wind wheel also utilized. It is known by calculation that MWD will produce electricity 3.9~6.4 times of that produced by present wind power device in commercial operation.

Publisher Summary This chapter presents a new method of calculating resonant frequency, referred to as standing wave minimal antinode method (SWMAM). This makes it possible to consider the influence of resistance, since zero antinode is no longer a necessity as in an ideal standing wave system. Numerical simulation will be made on three types of tubes for their resonant frequencies with three methods, focusing on the influences of impedance composition on the resonant frequency. The SWMAM is proved valid for calculating resonant frequency, after comparison with two traditional methods. It is convenient for analyzing the influence of impedance on the resonant frequency. The impedance of tube ends has obvious effect on resonant frequency when the resistance is not so large. When the end buffer volume is 0.5–3 times that of tube, the resistance fraction greatly affects the resonant frequency. Based on three different methods, numerical simulation has been made on three types of tubes for their resonant frequencies, focusing on the influences of impedance composition on the resonant frequency. Results under different conditions are used to discuss the equality and difference among these methods.

Background Risk factors for delirium following cardiac surgery are incompletely understood. The aim of this study was to investigate whether intra-operative pathophysiological alterations and therapeutic interventions influence the risk of post-operative delirium. Methods This retrospective cohort study was performed in a 12-bed cardiosurgical intensive care unit (ICU) of a university hospital and included patients consecutively admitted after cardiac surgery during a 2-month period. The diagnosis of delirium was made clinically using validated scores. Comparisons between patients with and without delirium were performed with non-parametric tests. Logistic regression was applied to identify independent risk factors. Results are given as number (percent) or median (range). Results Of the 194 consecutive post-cardiac surgery patients, 50 (26 %) developed delirium during their ICU stay. Univariate analysis revealed that significant differences between patients with and without delirium occurred in the following intra-operative variables: duration of cardiopulmonary bypass (184 [72–299] vs 113 (37–717) minutes, p