Study on Dynamic Guidance Obstacle Avoidance of UAV based on the Minimum Angle Shift

Xiong zhiyong,Yang Xiuxia,Zhang Yi,Hua Wei,Liu Xiaowei 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.3

With the extensive use of UAV, how to make the UAV avoid the obstacle and arrive at the destination has become a hot issue. To make the angle shift minimum, a method on dynamic guidance obstacle avoidance of UAV based on the minimum angle shift is proposed, considering the constraints such as the completion time of obstacle, the motor performance, the direction of velocity after obstacle avoidance and so on, determining the range of guidance parameters. In the meanwhile, the obstacle method is extended to 3D-space based on 2D. Moreover, numerical simulations are carried out to verify the effectiveness of the method.

Study on Dynamic Guidance Obstacle Avoidance for UAV

Xiong Zhiyong,Yang Xiuxia,Zhang Yi,Hua Wei,Zhou Weiei 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.8

With the flight environment becoming more and more complex, how to avoid the moving threat for the UAV under the dynamic environment and complete the mission become a key problem. With the idea of guidance, using the method of dimension reduction, the dynamic guidance obstacle avoidance method in three dimensional spaces is given. Considering the collision avoidance completion time and the UAV’s maneuverability, the parameters range of obstacle avoidance navigation law are deduced. Simulation results show the validity of the algorithm.

The influences of lateral leakage on hysteresis effects in flexible organic light-emitting diodes array

Xiong Zhiyong,Wen Zhuoqi,Cui Zhongjie,Mei Shiliang,He Haiyang,Duan Zhongtao,Zhang Wanlu,Xie Fengxian,Guo Ruiqian 한국물리학회 2023 Current Applied Physics Vol.45 No.-

Hysteresis effects in self-luminous devices like organic light-emitting diodes (OLEDs) and perovskite light-emitting diodes (PeLEDs) have been discovered recently, besides emerging in thin film transistors (TFTs). However, the influences of lateral leakage caused by next-door devices on hysteresis effects in flexible OLEDs array have rarely been demonstrated. To mitigate the impact of lateral leakage and figure out the detailed relationship with hysteresis effects, a series of experiments for OLEDs array involving p-doping in holes transport layer (HTL) were employed. It is found that the lateral leakage and hysteresis effects have a trade-off exhibition, which means stronger lateral leakage has induced weaker hysteresis effects. In order to get rid of the role of lateral leakage, the experiments with mono blue devices were also performed to substantiate the intrinsic hysteresis effects existence. The research opens the possibility of considering more internal relationships between different performances on self-luminous arrays for their actual application.

Effects of the Microstructure of Copper Through-Silicon Vias on their Thermally Induced Linear Elastic Mechanical Behavior

ZhiYong Wu,Zhiheng Huang,Yucheng Ma,Hua Xiong,Paul P. Conway 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.1

Through-silicon vias (TSVs) have been investigated extensively in recent years. However, the physical mechanisms behind some of the common problems associated with TSVs, such as the protrusion of Cu vias, are still unknown. In addition, since the dimensions of TSVs have been shrunk to microscopic levels, the sizes of the microstructural features of TSVs are no longer small compared to the dimensions of the vias. Therefore, the role and importance of the microstructural features of TSVs need to be studied to enable more accurate reliability predictions. This study focused on the effects the microstructural features of TSVs, i.e., the Cu grains and their [111] texture, grain size distribution, and morphology, have on the thermally induced linear elastic behavior of the vias. The results of the study indicate that stress distribution in the model that takes into account the Cu grains, whose Young’s moduli and Poisson’s ratios are set according to their crystallographic orientations, is more heterogeneous than that in a reference model in which the bulk properties of Cu are used. Stresses as high as 250 MPa are observed in the via of the model that takes into consideration the Cu grains, while stresses in the via of the reference model are all lower than 150 MPa. In addition, smaller Cu grains in the vias result in higher stresses; however, the variation in stress owning to changes in the grain size is within 20 MPa. The frequency of the stresses ranging from 80 MPa to 100 MPa was the highest in the stress distribution of the vias, depending on boundary conditions. The stress level in the vias decreases with the decrease in the number of grains with the [111] texture. Finally, the stress level is lower in the model in which the grain structure is generated using a phase field model and is closer to that of the microstructures present in real materials.

Efficient Mining Maximal Subspace Differential Co-expression Patterns in Matrix Datasets : a General Earthquake Analysis Approach

Miao Wang,Zhiyong Xiong,Liang Xu,Lihua Zhang,Cheng Gong,Yi Hu,Yi Lin 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.3

The electromagnetic anomaly observations before earthquake, have been confirmed by many cases of strong earthquakes. The analysis of earthquake magnetic anomaly is an effective approach for seismo-precursor detection. Traditional frequent mining methods for electromagnetic matrix datasets analysis often find the co-related items. However, these methods may miss the items which are differential co-related patters under different datasets. Mining these differential co-related patterns is more valuable for inferring potential knowledge. In this paper, we develop an algorithm, MSPattern, to mine maximal subspace differential co-expression patterns. MSPattern constructs a weighted undirected item-item relational graph firstly. Then all the maximal co-related patterns would be mined using item-growth method in above graph. MSPattern also utilizes several techniques for producing maximal patterns without candidate patterns maintenance. Evaluated by real electromagnetic matrix datasets and the gene expression datasets, the experimental results show our algorithm can find some potential knowledge for earthquake analysis, and MSPattern algorithm is more efficient than traditional ones. The performance of MSPattern is also evaluated by empirical p-value and gene ontology, the results show our algorithm can find statistical significant and biological differential co-expression patterns.

Deep Neural Network Based Complex-Heterogeneous Cyberspace Cartographic Visualization

Lan Zhang,Zhiyong Liu,Guangxia Wang,Lei Xiong 한국멀티미디어학회 2023 The journal of multimedia information system Vol.10 No.2

It seems complicated to imagine our life without the Internet, but it is only a few decades old, and the Internet forms the most extensive cyberspace environment. Cyberspace is the non-physical environment created by joint computers inter-operating on a network. The complex heterogeneous cyberspace is a virtual computer world that encompasses a variety of computers, network devices, and systems that have been manufactured by different entities. As an essential spatial cognitive tool, the map has significantly contributed to human civilization for thousands of years. However, the cartographic elements of traditional maps are mostly geospatial entities or phenomena, and only some people apply them to draw abstract and virtual cyberspace resources, resulting in the development of cyberspace cartography lagging. Additionally, the process of data visualization involves the conversion of data into visual forms such as charts and graphs, with the aim of effectively conveying the data's importance. The cartographic visualization is to realize the visual expression of cyberspace, which is an essential basis for understanding cyberspace. Therefore, this paper introduces a deep neural network (DNN) to study complex-heterogeneous cyberspace cartographic visualization. At first, locally linear embedding is adopted to reduce the data dimensionality. Then, DNN is used to train the cartographic coordinates data obtained after data dimensionality reduction. Finally, several different data modeling methods are studied concerning temporal and spatial attributes to achieve complex-heterogeneous cyberspace cartographic visualization effectively. The simulation is powered by datasets sourced from cyberspace, which are accessible via data.world. The results of the simulation demonstrate that the suggested approach is superior in efficiency when compared to the baseline methods.

Effects of Molecular Structure of Carboxyl-Containing Vinyl Monomers on Sizing Properties of Feather Keratin Graft Copolymer

Manli Li,Enqi Jin,Zhiyong Qiao,Yuting Xiong 한국섬유공학회 2019 Fibers and polymers Vol.20 No.9

In order to study the effects of molecular structure of carboxyl-containing vinyl monomers on applicationperformance of feather keratin (FK) graft copolymer for warp sizing, three kinds of carboxyl acids, i.e. acrylic acid (AA),methacrylic acid (MAA), and itaconic acid (IA), were grafted onto molecular chains of FK through initiation of K2S2O8-NaHSO3 redox system. FK-g-PAA, FK-g-PMAA, and FK-g-PIA with similar grafting ratios around 31 % were prepared assizing agents. Major sizing properties of the three grafted keratins were studied in terms of water-solubility, apparentviscosity, contact angles of sizing paste on cotton fibers, mechanical properties of sizing film, and adhesion to fibers. It wasfound that sizing properties of the grafted FK strongly depended on molecular structure of the carboxyl-containing vinylmonomers. In view of overall performance of the grafted keratin sizes, the most appropriate carboxyl-containing vinylmonomer should be AA.

A Novel Social Context-Aware Data Forwarding Scheme in Mobile Social Networks

Fang Xu,Huyin Zhang,Min Deng,Ning Xu,Zhiyong Wang,Zenggang Xiong,Conghuan Ye 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.6

Routing in disconnected delay-tolerant mobile ad hoc networks (MANETs) continues to be a challenging issue. Several works have been done to address the routing issues using the social behaviors of each node. Mobile Social Networks (MSNs) are increasingly popular type of Delay Tolerant Networks (DTNs). The routing performance improves when knowledge regarding the expected topology and the social context information of the networks. In this paper, we introduce a new metric for data forwarding based on social context information, in which node’s social context information is used to calculate the encounter utility between a node and destination, and the social relationship of network nodes is used to calculate the betweenness centrality utility of a node. We combine two utility functions to derive the social strength among users and their importance. We also present social context-based data forwarding algorithm for routing decision. Extensive simulations on real traces show that the introduced algorithm is more efficient than the existing algorithms.