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The design and optimization of antennas, electromagnetic propagation, radio frequency (RF), and channel characterization are vital to the performance of the system in the rapidly developing area of wireless communication. Antennas are electronic components that transform electrical currents into electromagnetic waves and vice versa. They are critical to the operation of any wireless network and their design and optimization are therefore of paramount importance. The goal of this research was to find out how different factors, like antenna type, electromagnetic environment, RF, and channel characteristics, affect the efficiency of a wireless network. Multipath fading of 8 dB, shadow fading of 3 dB, and path loss of 100 dB were used in the study with a microstrip antenna in a suburban propagation scenario at an RF frequency of 5 GHz. Antenna design, electromagnetic propagation scenario, radio frequency (RF), and channel characteristics were all shown to have an impact on the wireless communication system performance. The performance metrics of the wireless sensor network were almost, but not quite, those that were hoped for in a real-world setting. Several avenues for future study are suggested, and the results have important implications for the design and optimization of wireless communication systems.

This paper discusses the sustainable development of forest and rural tourism from the perspective of regional culture. This paper points out that there is a dialectical relationship between regional culture and the development of forest and rural tourism. This paper focuses on the impact of regional culture on the sustainable development of forest and rural tourism. On this basis, this paper analyzes the restrictive factors of the sustainable development of forest and rural tourism in China through AHP analysis and data-driven methods, and puts forward the basis, steps and ideas for the establishment of forest and rural tourism cultural mechanism. Finally, the sustainable development of forest and rural tourism in a certain area of China is studied. The experimental results show that the research results of this paper have a certain reference value for the research of forest rural tourism strategy driven by data.

Inorganic/polymer hybrid hydrogels generally exhibit excellent mechanical properties, while extra function include luminescence are extremely explored due to the further application in sensors and optoelectronic devices. Herein, we report the rare-earth (RE) complex/silica nanoparticles (SNs) luminescent hybrid polyethylene glycol (PEG) hydrogels showing stable luminescence. The hybrid hydrogels coordinated with RE (Eu3+) complex are fabricated via a convenient in situ photocrosslinked procedure. The coordination polymers showed red luminescent color under the 365 nm UV irradiation. Furthermore, the hybrid hydrogel exhibited long luminescence lifetime. These properties of hybrid luminescent hydrogel gave rise to a great improvement in the potential applications as a soft material.

Muglad Basin, one of the interior passive rift basins in Africa, has experienced multi-cycle passive rifting and superimposition evolution, which distinguishes itself from the active rift or single-cycle passive rift or typical multi-cycle superimposed basins. By application of analysis workflows & approaches to the superimposed basins, including the identification of key geological events during the evolutionary processes and stage division of the evolutionary history, the proto-type basins at the key periods were restored. And based on the analysis on the spatiotemporal difference in rifting intensities, superimposition processes & styles, the superimposition types of each depression or sag as well as its accumulation modes of oil & gas were established. Results show that accompanying with the breakup of Gondwana, and evolution of Atlantic Ocean, Indian Ocean and Red Sea surrounding the Africa Plate, Muglad Basin has experienced three evolutionary periods, namely, the deposition period of Abu Gabra Formation (AG Formation for short) in the Early Cretaceous, the deposition period of Darfur Group in the Late Cretaceous, and the deposition period of Tendi Formation in the Cenozoic. The proto-type basin at Early Cretaceous features several separate grabens and half-grabens, which was produced under the extensional environment having a close relationship with the spreading of Atlantic Ocean; the pro-type basin at Late Cretaceous features the successive development of those early grabens and half-grabens, which was produced under the extensional environment having a close relationship with the rapid movement of Indian Plate. And the proto-type basins at the Cenozoic were mainly confined within the grabens and half-grabens in Kaikang Depression, which was largely affected by the opening of Red Sea. According to the different intensities of three-cycle rifting in each depression or sag and the distinctive processes of tectonic subsidence and sediment filling, the superimposition types of three-cycle rifting were divided into three types, namely, the early-developed, the successive and the dynamic. And the early-developed sag could be represented by the Sufyan Sag, which features the drastically decreasing intensity of three-cycle rifting. In those sags, the amount of basement subsidences and sediment fillings during the first-cycle rifting and post-rifting could account for 79% similar to 82% of the total subsidences and fillings. And the third cycle of rifting and post-rifting was so weak that it was difficult to interpret the layers in seismic section, and even in the logging, it was always omitted. Fula Sag was the most typical sag of the successive. Those sags feature the gradually decreasing intensity of three-cycle rifting & post-rifting. Unlike the former one, the second cycle of rifting & post-rifting still remains quite strong in intensity, which could be proved by the fact the thickness of Darfur Group (Late Cretaceous) in Fula Sag is larger than that of Bentiu Formation (Early Cretaceous) which was deposited during the first cycle of post-rifting. Kaikang Depression was the most typical depression of the dynamic, which features the relatively continuous intensity of the three cycles. When comparing with the formers, every cycle of the three cycles in the Kaikang Depression was larger than any of the early-developed and the successive. Even in the third cycle of rifting & post-rifting, the amount of subsidence and sediment fillings was as much as 2,000m. The spatiotemporal differences in intensities of three-cycle rifting & post rifting determine the differences in petroleum geological conditions for hydrocarbon accumulation and distribution. The dominant play in the early-developed sags is the lower play, and that in the successive sags is the middle play. However, the upper plays were the most dominant plays in those dynamic sags. The study of multi-cycle superimposed passive rift basin in this paper would not only contribute and enrich the research on the structural feature, evolutionary history as well as its effect on the hydrocarbon accumulation of other rift basins in the world, but also had a practical significance in making further strategies for exploration in these basins.

The Intelligent Connected Vehicle (ICV) related to the communication of the stakeholders has become a large and open ecosystem. From the automobile ecosystem, it can be found that there are many attack entrances everywhere, which will bring a lot of risks and threats. In this work, we have summarized the seven major attack entrances of automobile cyber security, and proposed the corresponding six key protection strategies of intelligent and connected vehicle.

The composite particles composed of quantum dots coated with silica and grafted with copolymer of polyethylene glycol and low molecular weight polyethylene terephthalate (QDs@SiO2-PEG-LMPET) are synthesized. The internal QDs provide luminescent performance and combine with SiO2 to form QDs@SiO2 with good dispersion to solve the defect that small-sized SiO2 is prone to agglomerate. The block polymer LMPET-PEG grafted on the surface can make the composite particles better compatible with the PET matrix. In summary, QDs@SiO2-PEG-LMPET not only play the same role as SiO2 to enhance the crystallization performance of PET matrix, but also provide stable luminescence performance, which is multifunctional additive with broad application prospects.

The aim of this paper is to propose a digital human body model method based on the latest version of national standard anthropometric data, and a hierarchical model method is used to construct the joint motion hierarchy which can be edited and controlled in real time; a three-dimensional mesh skin model is drawn, which can be combined with bone binding into a two-layer digital mannequin, and implement it in software. Digital human body as a true embodiment of the human body in the digital world received wide attention in different areas, but it was not a very good method to make the digital human body meet the data accurate and can finish the tasks. The digital human body model not only has the realistic Chinese characteristics, but also can satisfy the simulation and application.

This study investigates the reactor core physical properties of the AP1000®, which applies the MCNP4a program to model the AP1000 reactor core with the parameters and data from the design control document (DCD, Rev. 19) of the AP1000 Nuclear Power Plant, which has been submitted to the nuclear regulatory commission (NRC). The model is applied to calculate and verify the physical parameters of AP1000 core design. The results match well with the design values in the DCD of the AP1000 nuclear power plant. The model will be modified according to the actual reactor core arrangement, such as AP1000 reactors at China's Sanmen and Haiyang sites, and then compared with the commissioning test results in the future.

Multi-effect distillation (MED) system with a top brine temperature lower than 70°C, is one of the most successful desalination technologies. In this paper, a lab-scale vertical tube MED system was performed for salinity wastewater desalination of petrochemical enterprises, and five salinity wastewater treatment schemes including different combinations of evaporator types were investigated. As a result, the falling-falling-climbing (FFC) system was considered as the optimal scheme. Then, the operation parameters including the feedwater salinity, temperature, flow rate, and the fresh steam flow rate were further optimized. The results indicated that the CR and gained output ratio (GOR) would rise up by increasing effect numbers, fresh steam flow rate, and feedwater temperature. While CR and GOR would fall down with the increase of the feedwater salinity and flow rate. Therefore, the optimal operation parameters were experimentally determined as follows: the feedwater with salinity of 0.6%, flow rat...

As the amount of target characteristics data increasing rapidly, the tradition methods cannot satisfy the need of the storage and management of those data. According to the features of those data, a new storage system is proposed base on RDBMS and Hadoop. The structured data and the metadata of unstructured data is stored in the RDBMS under certain schema, while the large amount of unstructured one allocated among numbers of nodes in the hadoop cluster. In order to maximize the superiority of storage, the HBase is used for storing massive small-size unstructured data and the HDFS is applied for holding the large-scale ones. Meanwhile, the access control and the multi-thread upload and download approach combined with load balancing and caching mechanism is applied for improving the efficiency of data transmission. Experiment results show that the proposed storage system is reasonable and practicable.

Principal component analysis (PCA) is a statistical technique commonly used in multivariate data analysis. However, PCA can be difficult to interpret and explain since the principal components (PCs) are linear combinations of the original variables. Sparse PCA (SPCA) aims to balance statistical fidelity and interpretability by approximating sparse PCs whose projections capture the maximal variance of original data. In this paper we present an efficient and paralleled method of SPCA using graphics processing units (GPUs), which can process large blocks of data in parallel. Specifically, we construct parallel implementations of the four optimization formulations of the generalized power method of SPCA (GP-SPCA), one of the most efficient and effective SPCA approaches, on a GPU. The parallel GPU implementation of GP-SPCA (using CUBLAS) is up to eleven times faster than the corresponding CPU implementation (using CBLAS), and up to 107 times faster than a MatLab implementation. Extensive comparative experiments in several real-world datasets confirm that SPCA offers a practical advantage., Comment: submitted to Multimedia Tools and Applications

Si nanocrystals (Si nc) were formed by the implantation of Si(+) into a SiO2 film on (100) Si, followed by high-temperature annealing. High-resolution transmission electron microscopy has been used to investigate the dislocations in the Si nc produced by a high-dose (ion fluence of 3 x 10(17) cm(-2)) implantation. Three different kinds of dislocations, namely perfect, extended and mismatch dislocations, have been observed in some Si nc. The possible formation mechanism for these dislocations has been discussed. The dislocations in the Si nc are expected to have a great influence on the photoluminescence from Si nc embedded in SiO2.