Spatial Throughput Maximization of Wireless Powered Communication Networks

Wireless charging is a promising way to power wireless nodes' transmissions. This paper considers new dual-function access points (APs) which are able to support the energy/information transmission to/from wireless nodes. We focus on a large-scale wireless powered communication network (WPCN), and use stochastic geometry to analyze the wireless nodes' performance tradeoff between energy harvesting and information transmission. We study two cases with battery-free and battery-deployed wireless nodes. For both cases, we consider a harvest-then-transmit protocol by partitioning each time frame into a downlink (DL) phase for energy transfer, and an uplink (UL) phase for information transfer. By jointly optimizing frame partition between the two phases and the wireless nodes' transmit power, we maximize the wireless nodes' spatial throughput subject to a successful information transmission probability constraint. For the battery-free case, we show that the wireless nodes prefer to choose small transmit power to obtain large transmission opportunity. For the battery-deployed case, we first study an ideal infinite-capacity battery scenario for wireless nodes, and show that the optimal charging design is not unique, due to the sufficient energy stored in the battery. We then extend to the practical finite-capacity battery scenario. Although the exact performance is difficult to be obtained analytically, it is shown to be upper and lower bounded by those in the infinite-capacity battery scenario and the battery-free case, respectively. Finally, we provide numerical results to corroborate our study.Comment: 15 double-column pages, 8 figures, to appear in IEEE JSAC in February 2015, special issue on wireless communications powered by energy harvesting and wireless energy transfe

Numerical Complete Solution for Random Genetic Drift by Energetic Variational Approach

In this paper, we focus on numerical solutions for random genetic drift problem, which is governed by a degenerated convection-dominated parabolic equation. Due to the fixation phenomenon of genes, Dirac delta singularities will develop at boundary points as time evolves. Based on an energetic variational approach (EnVarA), a balance between the maximal dissipation principle (MDP) and least action principle (LAP), we obtain the trajectory equation. In turn, a numerical scheme is proposed using a convex splitting technique, with the unique solvability (on a convex set) and the energy decay property (in time) justified at a theoretical level. Numerical examples are presented for cases of pure drift and drift with semi-selection. The remarkable advantage of this method is its ability to catch the Dirac delta singularity close to machine precision over any equidistant grid.Comment: 22 pages, 11 figures, 2 table

How does green finance affect the low-carbon economy? Capital allocation, green technology innovation and industry structure perspectives

The development of green finance and social low-carbon transformation is an essential concern for academia and industry. Based on Chinese provincial panel data spanning the period 2005–2019, we introduce the Cobb-Douglas production function and spatial Durbin and dynamic panel threshold models to deeply analyse the impact of green finance on the low-carbon economy. The mechanism test demonstrates that the scale, technique, and structural effects of green finance play a significant role in the low-carbon economy: they correct capital mismatch, promote green technology innovation, and optimise industrial structure. Meanwhile, green finance not only promotes the local low-carbon economy construction process, but also generates spatial spillover effects on neighbouring regions; however, there is regional heterogeneity in the impact of the transmission mechanism. Furthermore, only when capital mismatch is severe, and the low-end industrial structure poor is the positive impact of green finance on the low-carbon economy highlighted based on scale and structural effects; the ability of green finance to contribute to the low-carbon economy through the technique effect has been more stable and significant. This emphasises that green technology innovation is key to supporting low-carbon development in the long run

The Cumulative Distribution Function Based Method for Random Drift Model

In this paper, we propose a numerical method to uniformly handle the random genetic drift model for pure drift with or without natural selection and mutation. For pure drift and natural selection case, the Dirac $\delta$ singularity will develop at two boundary ends and the mass lumped at the two ends stands for the fixation probability. For the one-way mutation case, known as Muller's ratchet, the accumulation of deleterious mutations leads to the loss of the fittest gene, the Dirac $\delta$ singularity will spike only at one boundary end, which stands for the fixation of the deleterious gene and loss of the fittest one. For two-way mutation case, the singularity with negative power law may emerge near boundary points. We first rewrite the original model on the probability density function (PDF) to one with respect to the cumulative distribution function (CDF). Dirac $\delta$ singularity of the PDF becomes the discontinuity of the CDF. Then we establish a upwind scheme, which keeps the total probability, is positivity preserving and unconditionally stable. For pure drift, the scheme also keeps the conservation of expectation. It can catch the discontinuous jump of the CDF, then predicts accurately the fixation probability for pure drift with or without natural selection and one-way mutation. For two-way mutation case, it can catch the power law of the singularity. %Moreover, some artificial algorithms or additional boundary criteria is not needed in the numerical simulation. The numerical results show the effectiveness of the scheme

Novel mini/micro-dystrophin genes restore nNOS to the sarcolemma and improve the therapeutic outcome for Duchenne Muscular Dystrophy [abstract]

Duchenne muscular dystrophy (DMD) is a muscle disease caused by mutations of the dystrophin gene. Gene replacement therapy represents a very promising approach to cure this disease. The dystrophin gene is one of the largest genes in the genome and it exceeds the carrying capacity of adenoassociated viral vector (AAV) and lentiviral vector, the most powerful gene delivery vehicles for muscle. The truncated mini/micro-dystrophin genes have been developed to overcome this hurdle. Despite improvement of muscle function and the dystrophic phenotype by these mini/micro-dystrophin genes, none of them can restore sarcolemmal neuronal nitric oxide synthase (nNOS). Sarcolemmal nNOS plays a crucial role in maintaining blood perfusion during muscle contraction. In DMD patients, sarcolemmal nNOS is lost. Consequently, it leads to functional ischemia and muscle damage. To improve the therapeutic efficacy of the truncated dystrophin genes, one has to develop the new synthetic dystrophin genes with the ability to restore sarcolemmal nNOS. The motif for nNOS sarcolemmal localization was identified and incorporated into new mini/microdystrophin genes. The effect of sarcolemmal nNOS restoration on the muscle functions, blood perfusion in contracting muscle and exercise performance was evaluated. Dystrophin spectrin-like repeats 16 and 17 (R16/17) are required for sarcolemmal nNOS localization. The synthetic mini/micro-dystrophin genes carrying R16/17 significantly improved muscle function, blood perfusion and exercise capacity. Our newly developed R16/17 mini/micro-dystrophin genes provide functions close to that of the full-length dystrophin gene. They represent excellent candidate genes for DMD gene therapy

Basic Public Cultural Services Problems and Countermeasure Analysis in Rural

Overall balanced development of urban and rural culture is an important part of the current public cultural service system, it is one of the basic means of promoting social development. This article from the perspective of the outstanding problems of the rural public cultural service, analyses the basic reasons which restrict the development of the rural public culture, then proposed to strengthen and improve the countermeasure thinking of rural public cultural services

Sub-daily simulation of mountain flood processes based on the modified soil water assessment tool (SWAT) model

Floods not only provide a large amount of water resources, but they also cause serious disasters. Although there have been numerous hydrological studies on flood processes, most of these investigations were based on rainfall-type floods in plain areas. Few studies have examined high temporal resolution snowmelt floods in high-altitude mountainous areas. The Soil Water Assessment Tool (SWAT) model is a typical semi-distributed, hydrological model widely used in runoff and water quality simulations. The degree-day factor method used in SWAT utilizes only the average daily temperature as the criterion of snow melting and ignores the influence of accumulated temperature. Therefore, the influence of accumulated temperature on snowmelt was added by increasing the discriminating conditions of rain and snow, making that more suitable for the simulation of snowmelt processes in high-altitude mountainous areas. On the basis of the daily scale, the simulation of the flood process was modeled on an hourly scale. This research compared the results before and after the modification and revealed that the peak error decreased by 77% and the time error was reduced from +/- 11 h to +/- 1 h. This study provides an important reference for flood simulation and forecasting in mountainous areas

(Z)-3α-(1,3-Dioxoisoindolin-2-yl)-17(20)-pregnene

The title compound, C29H37NO2, crystallized with two independent mol­ecules in an asymmetric unit in which the conformation of the cyclo­hexyl ring of the pregnene moiety bonded to the 3α-(1,3-dioxoisoindolin-2-yl)- ring system differs: in one mol­ecule it is in a chair conformation, while in the other it exhibits a half-chair conformation. The other six-membered rings in the pregnene moiety are in chair conformations and the five-membered rings are in envelope forms in both mol­ecules. In both mol­ecules, the 3α-(1,3-dioxoisoindolin-2-yl)- ring systems are individually approximately planar, with r.m.s. devtaions 0.0148 and 0.0264 Å. The structure is consolidated by inter­molecular C—H⋯O hydrogen-bonding inter­actions involving the carbonyl O atoms and methyl, methyl­ene and methyl­idyne groups, resulting in a two-dimensional structure