Dual-polarized spatial-temporal propagation measurement and modeling in uma o2i scenario at 3.5 GHz

Outdoor-to-indoor (O2I) coverage in urban areas by using the sub-6 GHz (sub-6G) band is important in the fifth generation (5G) mobile communication system. The spatial-temporal propagation characteristics in different polarizations in the 5G spectrum are crucial for the network coverage. In this paper, we measured the urban macrocell (UMa) O2I channels at 3.5 GHz in the space, time, and polarization domains simultaneously. The channel sounder utilized two ±45° polarized antenna arrays. The transmitter (TX) was placed on the rooftop of a five-storey building to emulate a base station and the receiver (RX) was moved in the corridors on different floors in another building to emulate user equipments (UEs). We obtained the small-scale parameters of excess delay, power, and azimuth/elevation of arrival (AoA/EoA) of individual multipath components (MPCs), the propagation profiles of azimuth/elevation power spectrum (APS/EPS) and power delay profile (PDP), and the large-scale parameters including azimuth/elevation spread of arrival (ASA/ESA) and delay spread (DS). Based on the measurement results, we propose the lifted-superposed Laplace distribution (LS-Laplace) function and lifted-superposed normal distribution (LS-Normal) function to model the APS and EPS, respectively, and a three-phase model for the PDP. We find that the ASA and ESA follow the lognormal distribution and the DS has a Rayleigh distribution. We also reveal the impact of surrounding environments and polarization on the channel propagation profiles and statistical characteristics. The measurement results and channel models in this paper provide reference for the design and deployment of the 5G system to exploit the spatial and polarization diversities in the UMa O2I scenario.This work was supported in part by the National Natural Science Foundation of China under Grant 61571370, Grant 61601365, and Grant 61801388, in part by the Key Research Program and Industrial Innovation Chain Project of Shaanxi Province under Grant 2019ZDLGY07-10, Grant 2019JQ-253, and Grant 2019JM-345, and in part by the China Postdoctoral Science Foundation under Grant BX20180262, Grant BX20190287, Grant 2018M641020, and Grant 2018M641019.Scopu

Shifting the limits in wheat research and breeding using a fully annotated reference genome

Introduction: Wheat (Triticum aestivum L.) is the most widely cultivated crop on Earth, contributing about a fifth of the total calories consumed by humans. Consequently, wheat yields and production affect the global economy, and failed harvests can lead to social unrest. Breeders continuously strive to develop improved varieties by fine-tuning genetically complex yield and end-use quality parameters while maintaining stable yields and adapting the crop to regionally specific biotic and abiotic stresses. Rationale: Breeding efforts are limited by insufficient knowledge and understanding of wheat biology and the molecular basis of central agronomic traits. To meet the demands of human population growth, there is an urgent need for wheat research and breeding to accelerate genetic gain as well as to increase and protect wheat yield and quality traits. In other plant and animal species, access to a fully annotated and ordered genome sequence, including regulatory sequences and genome-diversity information, has promoted the development of systematic and more time-efficient approaches for the selection and understanding of important traits. Wheat has lagged behind, primarily owing to the challenges of assembling a genome that is more than five times as large as the human genome, polyploid, and complex, containing more than 85% repetitive DNA. To provide a foundation for improvement through molecular breeding, in 2005, the International Wheat Genome Sequencing Consortium set out to deliver a high-quality annotated reference genome sequence of bread wheat. Results: An annotated reference sequence representing the hexaploid bread wheat genome in the form of 21 chromosome-like sequence assemblies has now been delivered, giving access to 107,891 high-confidence genes, including their genomic context of regulatory sequences. This assembly enabled the discovery of tissue- and developmental stage–related gene coexpression networks using a transcriptome atlas representing all stages of wheat development. The dynamics of change in complex gene families involved in environmental adaptation and end-use quality were revealed at subgenome resolution and contextualized to known agronomic single-gene or quantitative trait loci. Aspects of the future value of the annotated assembly for molecular breeding and research were exemplarily illustrated by resolving the genetic basis of a quantitative trait locus conferring resistance to abiotic stress and insect damage as well as by serving as the basis for genome editing of the flowering-time trait. Conclusion: This annotated reference sequence of wheat is a resource that can now drive disruptive innovation in wheat improvement, as this community resource establishes the foundation for accelerating wheat research and application through improved understanding of wheat biology and genomics-assisted breeding. Importantly, the bioinformatics capacity developed for model-organism genomes will facilitate a better understanding of the wheat genome as a result of the high-quality chromosome-based genome assembly. By necessity, breeders work with the genome at the whole chromosome level, as each new cross involves the modification of genome-wide gene networks that control the expression of complex traits such as yield. With the annotated and ordered reference genome sequence in place, researchers and breeders can now easily access sequence-level information to precisely define the necessary changes in the genomes for breeding programs. This will be realized through the implementation of new DNA marker platforms and targeted breeding technologies, including genome editing

Solving the green-fuzzy vehicle routing problem using a revised hybrid intelligent algorithm

Green logistics is an emerging area in supply chain management, which has been shown to have tremendous impacts in recent years to face the serious climate changes risks. In this paper, the fuel consumption and fuzzy travel time have been delineated in developing and solving the green-fuzzy vehicle routing problem as an extension of the celebrated VRP in which routes are performed to reduce the total expenditure. Different from the existing solution manners, we transform the original fuzzy chance constrained programming model into an equivalent deterministic model, and then revise the original hybrid intelligent algorithm by replacing the embedded fuzzy simulation with analytical function calculation. Finally, a comparative study with the corresponding literature is performed, which shows that the revised algorithm can not only improve the solution accuracy but also shorten the runtime greatly

Cooperative Secondary Encryption for Primary Privacy Preserving in Cognitive Radio Networks

Aiming at protecting primary privacy messages and supporting secondary quality-of-service (QoS), we propose a secondary encrypted secure strategy for cognitive radio networks. In this scheme, a primary system directly transmits privacy messages or employs pre-transmitted secure secondary messages to encrypt the primary privacy information, and the secondary system acquires a fraction of the interference-free licensed spectrum. Following this idea, we consider two secure communication scenarios: the non-buffer scenario and the buffer-aided scenario. For the non-buffer scenario, the primary system first evaluates the channel quality of the direct transmission link. Then, the primary transmitter adaptively chooses to directly transmit the privacy messages or employ the encryption of the secure secondary messages according to the evaluation results. For this scenario, we investigate the primary ergodic secrecy performance and the secondary average performance. For the buffer-aided scenario, the secure secondary messages can be stored in the buffers at both the primary transmitter and receivers. According to the buffer states and channel quality, the primary system adaptively chooses to directly transmit the primary privacy information, permit the secondary secure transmission, or utilize the encryption of the stored secure secondary information. For this scenario, we also investigate the performances of both the primary and secondary systems, and derive the closed-form expression of the primary information delay. Numerical results are given to prove that the proposed scheme can provide privacy preserving for the primary information and acquire high secondary average transmission rate. - 2013 IEEE.This work was supported in part by the National Natural Science Foundation of China under Grant 61901379, Grant 61901381, and Grant 61571370, in part by the Natural Science Basic Research Plan in Shaanxi Province of China under Grant 2019JQ-253, Grant 2019JQ-631, Grant 2018ZDCXL-GY-03-04, and Grant 2019ZDLGY07-10, in part by the Fundamental Research Funds for the Central Universities under Grant 31020180QD095, in part by the Open Research Fund of the National Mobile Communications Research Laboratory, Southeast University under Grant 2020D04, in part by the Advance Research Program on Common Information System Technologies under Grant 315075702, in part by the Medical Science and Technology Research Foundation of Guangdong under Grant B2018108, and in part by the Youth Creative Talent Project (Natural Science) of Guangdong under Grant 2017KQNCX041.Scopu