A frequency-reconfigurable bow-tie antenna for Bluetooth, WiMAX, and WLAN applications is proposed. The radiator printed on two sides of the substrate fed by a microstripline continued pair parallel strips. By embedding p-i-n diodes over arms, effective electrical length can be changed, leading to an electrically tunable operating band. simple biasing circuit used in this design eliminates need extra bias lines, thus avoids distortion radiation patterns. Measured results are good agreement...

The remote sensing image captioning has attracted wide spread attention in field due to its application potentiality. However, most existing approaches model limited interactions between content and sentence fail exploit special characteristics of the images. We introduce a novel recurrent semantic gate (RASG) framework facilitate this article, which integrates competitive visual features mechanism generate better context vector for images every time as well enhances representations current...

With the rapid development of big data and Internet things (IOT), number networking devices volume are increasing dramatically. Fog computing, which extends cloud computing to edge network can effectively solve bottleneck problems transmission storage. However, security privacy challenges also arising in fog-cloud environment. Ciphertext-policy attribute-based encryption (CP-ABE) be adopted realize access control systems. In this paper, we propose a verifiable outsourced multi-authority...

A novel direction of arrival (DoA) estimation method based on amplifier-integrated active metasurface is proposed to find multisource directions by a single-channel system. Nonuniformly periodic time modulation (NPTM) the reduces hardware complexity taking full advantage spectral resources. As result, only partial elements are required achieve 2-D DoA estimation, while remaining can be redesigned and encoded control electromagnetic waves. Thus, adaptive beamsteering expected realize in...

Abstract The integrated design of radiation and stealth holds significant importance for radar communication camouflage. Currently, systems primarily rely on radomes off‐band stealth. However, achieving in‐band by absorbing materials is challenging. Even more challenging the dynamic control both Therefore, a novel space‐time‐coding metasurface proposed modes regulation. By adjusting two PIN diodes loaded meta‐atom, switching between scattering can be achieved. A 1‐bit reflection phase...

Non-speech sound-awareness is important to improve the quality of life for deaf and hard-of-hearing (DHH) people. DHH people, especially young, are not always satisfied with their hearing aids. According interviews 60 young students, a ubiquitous tool emergency social events that works in diverse environments desired. In this paper, we design UbiEar, smartphone-based acoustic event sensing notification system. Core techniques UbiEar light-weight deep convolution neural network enable...

This paper proposes a new frequency-reconfigurable antenna (FRA) which consists of quasi-Sierpinski fractal dipoles integrating with dual-band high-impedance surface (HIS). The can operate in three frequency bands, i.e., X-band, Ku-band, and Ka-band, by changing the states two switches. In order to achieve low-profile design good front-to-back radiation ratio, HIS is presented as reflector. composed an array square patches etching slots, has in-phase reflection bands for X-band Ku-band be...

Two novel metamaterial-inspired antennas applied for 4G mobile communication are proposed in this letter. Antenna 1 takes a triangular electromagnetic resonator (TER) as its radiator fed by coplanar waveguide (CPW). After the model building and simulation, three frequency bands of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$1.78\sim 1.84~\hbox{GHz}$</tex></formula> , Notation="TeX">$2.34\sim...

As vehicular equipment is becoming more and intelligent, the information service, as main means of capturing information, has been far from able to meet needs occupants [1, 2]. Cloud computing, with its powerful computing storage capabilities, convenient network access, energy saving excellent scalability, reliability, availability, other advantages, can be an effective solution limitations existing automotive services. Connected cloud which combines VANETs, characteristics both a platform...

Remote sensing images play an important role in various applications. To make it easier for humans to understand remote images, the task of image captioning attracts more and researchers' attention. Inspired from way human receives visual information, attention mechanism has been widely used understanding. catch scene information improve stability generated sentences, a new called is proposed. Except current via hidden state long shortterm memory network (LSTM), our proposed method...

Abstract Radiation‐stealth integration, merging radiation regulation and scattering suppression into a unified framework, is essential for advanced radar communications stealth technology. However, current state‐of‐the‐art solutions that simultaneously modulate characteristics encounter two main challenges: limited scalability due to high energy demands from active components, constrained bandwidth stemming the inherent incompatibility between scattering. Here, passive folded metasurfaces...

This letter presents a novel 2-bit amplification metasurface cell (APMC) for nonreciprocal reflection of linearly polarized EM waves into high-intensity orthogonal waves. The APMC consists four parts, reconfigurable receiving patch, phase shifter, power amplifier circuit, and reradiating patch. By tuning the bias voltage p-i-n diodes mounted on patch could manipulate reflected with discrete states. A is placed between shifter to increase energy intensity wave. In addition, an orthomode...

In realistic Vehicular Ad hoc NETworks (VANETs), due to the existence of three-dimensional (3D) scenarios, such as viaduct, tunnel and ramp, distribution vehicles is non-planar. However, existing routing protocols in VANETs are mainly analyzed designed based on ideal plane scenarios. We call them plane-based protocols. this paper, we focus issues 3D scenarios VANETs. Through analysis, demonstrate that applied suffer a series severe problems, i.e., hop count increases delivery ratio...

Two-parity maximum distance separable (MDS) array codes achieve the lowest storage overhead for tolerating two erasures. In this letter, we propose new classes of twoparity MDS over finite field F <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , with which each single node failure can be recovered by reading minimum amount data from surviving node.

Abstract In the present paper, a brief review for some existing critical plane‐based life prediction models is presented, and limitations of these in reflecting influence mean stress on fatigue are discussed. It found that effect normal damage has been well taken into account most models, while shear not considered models. Therefore, new multiaxial high cycle model proposed this paper to effects both stresses. The Walker factor sensitivity index introduced developed criterion consider...

The trend of globalization motivates people to travel more often different cities. In order provide better suggestions for travelers, it is important understand their preferences venue types. this article, we investigate travelers' based on the check-in data collected from a popular location-based social application called Swarm. We conduct thorough analysis discover variation in between cities with characteristics, and build model predicting types interests each city. Our experimental...

In order to ensure the communication link stability in mobile FSO system, a new omni-directional optical antenna is designed. Being aimed at discontinuous tracking, novel beam control method based on error correction Kalman prediction algorithm (EC-KPA) proposed. The comparison of EC-KPA and conventional (KPA) given. Numerical simulations about are carried out. results show that accuracy improved 77% than KPA Gaussian noise situation, increase up 12.92 times strong situation. Therefore,...

As is known, the intersection-based geographic routing protocol a promising solution to information dissemination in realistic city environments. Also, there exists series of special issues for VANETs urban area. Aiming tackle these issues, many such protocols have been proposed academia. In this paper, we present four important scenarios which not only strongly affect performance protocols, but also will be key factors prompt us redesign more suitable protocols. Those include intermittent...

Phased arrays have been widely used in microwave power transmission. The efficiency of rectenna is closely related to the received density. Therefore, it necessary accurately analyze radiation performance transmitting array order achieve high-efficiency And meet long-distance and transmission requirements, needs characteristics large electricity sizes. direct numerical analysis method entire will bring huge cost computing time storage space. Subarray extrapolation a reasonably account for...