A new stability results for the backward heat equation

In this paper, we regularize the nonlinear inverse time heat problem in the unbounded region by Fourier method. Some new convergence rates are obtained. Meanwhile, some quite sharp error estimates between the approximate solution and exact solution are provided. Especially, the optimal convergence of the approximate solution at t = 0 is also proved. This work extends to many earlier results in (f2,f3, hao1,Quan,tau1, tau2, Trong3,x1).Comment: 13 page

An Efficient Transmission Power Design for SWIPT Multi-antenna Network Integrated by an Intelligent Reflecting Surface

In this work, intelligent reflecting surface (IRS) is integrated to improve the transmission power in the simultaneous wireless information and power transfer (SWIPT) system with hybrid time-switching (TS) users. The considered scenario includes one base station (BS), one IRS, and multiple TS users, where the BS transmits the information and energy signals to the receivers with IRS assistance. The sum transmission power minimization problem is formulated under the quality-of-service constraints of data rate and energy harvesting amount at the TS users and the equal time-switching periods. The successive convex approximation and alternating optimization methods are exploited to construct efficient algorithms for finding the suboptimal precoding beamforming vectors at the BS and the phase shifts at the IRS elements. Finally, the numerical results show convergence and significant improvement in performance as compared to conventional baseline schemes

Propagating arbuscular mycorrhizal fungi associated with coffee plant by using the herbaceous host

Coffee (Coffea spp.) is one of important industrial crops. Additionally, arbuscular mycorrhizal fungi (AMF) provide many benefits for plants such as increasing nutrient uptake, enhancing tolerance in drought and stress condition, etc. Therefore, preservation and propagation of AMF spores collected from coffee’s rhizosphere are necessary for coffee cultivation. The AMF preservation on coffee plant is not feasible because coffee is a long-term plants, which led to study on symbiotic ability of AMF on several short-term host plants (maize (Zea mays), plantain (Plantago spp.), rice (Oryza sativa), beggarticks (Bidens pilosa), and bahia grass (Pensacola bahia)) to maintain AM association. Investigation of symbiosis ability with four types of AMF spores showed that maize had the highest rate of fungal infection. The total number of AMF spore per 50g soil after 3 months of inoculation on maize reached 352 spores, which was 4.1 times higher than that of the origin while the lowest figure recorded in bahia grass is with only 2.3 times

FACTORS AFFECTING ECOTOURISM LOYALTY WITH THE MODERATING ROLE OF SOCIAL INFLUENCE - EMPIRICAL EVIDENCE IN VIETNAM

Today, ecotourism has become more common and attractive for tourists who love to explore nature and experience the cultural heritage. In the 4.0 age of technology, social networking not only helps visitors find suitable destinations to visit easily but also provides visitors with a place to leave comments or reviews after the trips. This study aims to qualify the relationships between electronic-worth-of-mouth (eWOM), social influence (SI), destination image (DI), tourist satisfaction (SAT), and ecotourism loyalty (EL). The study applied the PLS-SEM model to estimate 499 observations at ecotourism sites in Vietnam as empirical evidence. The research results show that all the factors in the research model have positive and significant effects on EL. In particular, DI and SAT, directly and indirectly, affect EL; while eWOM and SI only have direct effects on EL. Additionally, it was found that the effect of eWOM on EL increased with the moderating role of SI

Fuzzy gain scheduling control apply to an RC Hovercraft

The Fuzzy Gain Scheduling (FGS) methodology for tuning the Proportional – Integral – Derivative (PID) traditional controller parameters by scheduling controlled gains in different phases, is a simple and effective application both in industries and real-time complex models while assuring the high achievements over pass decades, is proposed in this article. The Fuzzy logic rules of the triangular membership functions are exploited on-line to verify the Gain Scheduling of the Proportional – Integral – Derivative controller gains in different stages because it can minimize the tracking control error and utilize the Integral of Time Absolute Error (ITAE) minima criterion of the controller design process. For that reason, the controller design could tune the system model in the whole operation time to display the efficiency in tracking error. It is then implemented in a novel Remote Controlled (RC) Hovercraft motion models to demonstrate better control performance in comparison with the PID conventional controller