In cognitive radio networks, collaborative spectrum sensing has been recognized as a key technology to enable secondary users (SUs) detect holes and opportunistically access primary licensed band without harmful interference. Most of the existing studies focus on 1D or 2D opportunity detection explicitly implicitly assume that all SUs share same opportunity. this paper, we first investigate issue joint spatial-temporal in 3D spectrum-heterogeneous space by leveraging location flexibility...

Fibers are used in many forms engineering applications–one of the most common being as reinforcement. Due to its renewable short natural growth cycle and abundance bamboo resources, fiber has attracted attention over other fibers. Bamboo a complex structure but offers excellent mechanical properties, which utilized textile, papermaking, construction, composites industry. However, fibers can easily absorb moisture prone corrosion limiting their use applications. Therefore, better...

Spectrum mapping has emerged as an important problem in wireless communications, which generates a spectrum map for the resource analysis and management. Given constrained transceiver volume limited energy consumption, how to effectively reconstruct situation by sampling data is pressing challenge mapping. In this paper, exploiting sparse nature of situation, we firstly attempt solve three-dimensional (3D) compressed way sensing. Then, develop quadrature right-triangular (QR) pivoting based...

Objective: To evaluate the operative outcomes and mechanisms of microvascular decompression in treating typical atypical trigeminal neuralgia. Methods: A group 45 patients with neuralgia 17 treated by micro-vascular from 2000 to 2002 were reviewed, including their clinical presentations, findings, outcomes. Results: Of neuralgia, mean duration was 3.1 years, age pain onset 60.3 years. Single division involved 20 (44.4%), 2 or 3 divisions other 25 (55.6%). During operation, artery compression...

The primary objective of this study is to incorporate the deep reinforcement learning (DRL) technique in conflict detection and resolution (CD&R) control strategies generate an optimised trajectory for air traffic controllers as reference, order improve efficiency reduce amount heading angle change. A DRL environment which can be applied CD&R agent training developed. receives current state multiple aircrafts a sector generates action change aircraft avoid conflict. K ‐Control...

Given the explosive growth of Internet Things (IoT) devices ranging from 2D ground to 3D space, it is a necessity establish spectrum map comprehensively present and effectively manage spatial resources in smart city infrastructures. By leveraging popularity location flexibility unmanned aerial vehicles (UAVs), we are able execute sampling with these emerging flying spectrum-monitoring (SMDs) at will. In this article, first brief survey show state-of-the-art studies on mapping. Then introduce...

Abstract A mismatch between the expansion coefficients of carbon fiber (CF, T300) and resin causes thermal deterioration at interface composite cryotanks. This study presents an effective method to enhance cryogenic interfacial properties a T300/epoxy (EP) composite, in which graphene oxide (GO)/attapulgite (ATP) hierarchical structures are chemically grafted onto surface T300. GO ATP were sequentially assembled on T300 surface, changed morphology optimized wettability T300/EP. Surface...

In this letter, we investigate the problem of remote spectrum mapping with inaccessible areas, whose goal is to estimate spatial power unreachable area a small amount sampled data in reachable area. First, establish compressed (RCSM) model considering constraint areas. Then, contrast traditional random or fixed sampling, propose an optimization algorithm for sampling location selection within accessible area, by directly optimizing from perspective matrix determination maximization. Its...

There is still a debate about the survival benefit of chemotherapy in stage III mucinous colon cancer, we then conduct comprehensive assessment efficacy adjuvant this population.The data used current study were extracted from Surveillance, Epidemiology and End Results (SEER) database. Chi-squared (χ2) test was to compared patient characteristics according histology. The outcome analysis cancer-specific (CSS). Univariable multivariable analyses carried out using Cox proportional hazards...

Close extra-thick coal seams are subject to the broken overburden of mined seams, and deformation damage roadways is serious, which affects safe operation mine. To reduce roadways, this paper studied law gob-side roadway in close through numerical simulation field monitoring, compared analyzed characteristics under different reinforcement support methods, determined optimal method, carried out verification. The obtained results indicated that showed asymmetric characteristics. large body...

Recent advances in deep reinforcement learning have shown promising potential results solving complex control problems. Inspired by these achievements, this paper, an environment which can be applied agent training to solve aircraft landing guidance problem is proposed. By environment, the receives current state of and runway a sector outputs action guide land at runway. The Deep Q Network (DQN) algorithm used verify feasibility environment. experimental show that train agent, produced...

Spectrum mapping has been increasingly important in various wireless communication applications, such as spectrum management, network planning, power control, dynamic access etc. In this letter, we consider the problem of time-varying situation map reconstruction using a small amount sampled data. contrast to traditional assumption that statistical signal propagation model is known, infer spatial characteristics from Then, greedy optimization applied calculate sampling locations with reduced...

To reveal the deformation and failure law of gob-side roadway (GSR) main influencing factors in close extra-thick coal seams, research methods field monitoring, theoretical analysis, numerical simulation are adopted this paper. Field monitoring data shows that microseismic events occur accumulate frequently surrounding rock some overlying key layers GSR. Large is experienced middle part near solid side, upper parts pillar floor. The strata GSR fractured to form a composite structure as...

Spectrum sensing is of crucial importance in the satellite communication networks to address increasingly severe spectrum scarcity problem. However, most schemes for detecting signal use traditional reflector antennas and have poor performance, especially under low signal-to-noise ratio (SNR). To tackle this issue, an energy detection (ED)-based scheme proposed by using phased-array (PAAs) networks. Moreover, closed-form expressions false alarm probability considering visibility...

Abstract To improve the impact toughness of polypropylene (PP), nano‐CaCO 3 was prepared by an in situ synthesis. The surface modified KH‐550 silane coupling agent and NDZ‐401 titanium acid ester agent. Nano‐CaCO /PP composite materials were fabricated through a melt‐blending method characterized, their mechanical properties analyzed. tensile strength PP improved significantly incorporation . When weight fraction 2%, maximum nanocomposites 293% 259%, respectively, values for neat PP....

Given the explosive growth of wireless devices ranging from 2D ground to 3D space, first task preceding any form dynamic spectrum management for smart city infrastructures is sensing heterogeneous situation in environments. However, challenge arises when increasing wide bandwidth and enormous geographic space meet power-limited CR receivers with constrained hardware capability. In this paper, a compressed wideband mapping model established by exploiting underlying sparse nature based on...

A low-emissive pigment of Al/SiO2/Fe2O3/FeO/Fe4[Fe(CN)6]3/Cr2O3/Cr (MAS) was prepared by chemical deposition method. The camouflage characteristics the coated fabric with paint mixed MAS, binder and other auxiliary in thermal infrared (IR 8~14 um) optical (0.38~1.2 region, studied emissivity tester, visible light camera imager. results show that MAS has low effectiveness compared Al/SiO2 pigment. Particularly, is green depositing metal oxide, ferrocyanide pure on surface Al/SiO2. reflectance...

The <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">α</sup> -stable distribution is a very flexible tool to model NonGaussian data. Stable distributions can allow for modeling infinite variance, skewness and heavy tails, but gives rise inferential problems related the estimation of stable parameters. In this work, we study using numerical Bayesian sampling techniques such as Markov chain Monte Carlo (MCMC), which simultaneously estimate four...