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排序方式: 共有8437条查询结果,搜索用时 15 毫秒
61.
无线传感器网络中基于神经网络的数据融合模型 总被引:4,自引:0,他引:4
数据融合技术通过减少传感器节点间的数据通信量,可以有效地节省传感器节点能耗,延长无线传感器网络的寿命.提出了独特的基于神经网络的数据融合模型(NNBA),该模型巧妙地将无线传感器网络的分簇层次结构与神经网络的层次结构相结合,将每个簇设计为一个三层感知器神经网络模型,通过神经网络方法从采集到的大量原始数据中提取特征数据,然后将特征数据发送给汇聚节点.以森林火灾实时监测网为应用实例,设计神经元模型及功能函数,并给出NNBA模型的仿真测试结果. 相似文献
62.
In this paper, a dual-band and reflective polarization converter based on metasurface is proposed. Its unit cell is composed of two layers of metal plates separated by a dielectric substrate. The simulation results show that the proposed converter is able to convert x- or y-polarized incident waves into cross-polarized waves perfectly in frequency bands of 6.75—10.59 GHz and 17.78—19.61 GHz, and the polarization conversion ratio (PCR) is nearly 100%, which can also convert linearly polarized waves into circularly polarized waves at four frequencies. It can be widely used in applications of radar satellites, antenna design and telecommunication with the function of realizing polarization conversion in two bands and achieving high PCR simultaneously. 相似文献
63.
Wang Xuwu Chen Lihan Zhu Wei Ni Yuan Xie Guotong Yang Deqing Xiao Yanghua 《Knowledge and Information Systems》2023,65(10):4335-4358
Knowledge and Information Systems - Entity linking is the task of resolving ambiguous mentions in documents to their referent entities in a knowledge graph (KG). Existing solutions mainly rely on... 相似文献
64.
Yunbo YANG Xiaolei DONG Zhenfu CAO Jiachen SHEN Shangmin DOU 《Frontiers of Computer Science》2023,17(5):175811
Oblivious Cross-Tags (OXT) [1 ] is the first efficient searchable encryption (SE) protocol for conjunctive queries in a single-writer single-reader framework. However, it also has a trade-off between security and efficiency by leaking partial database information to the server. Recent attacks on these SE schemes show that the leakages from these SE schemes can be used to recover the content of queried keywords. To solve this problem, Lai et al. [2 ] propose Hidden Cross-Tags (HXT), which reduces the access pattern leakage from Keyword Pair Result Pattern (KPRP) to Whole Result Pattern (WRP). However, the WRP leakage can also be used to recover some additional contents of queried keywords. This paper proposes Improved Cross-Tags (IXT), an efficient searchable encryption protocol that achieves access and searches pattern hiding based on the labeled private set intersection. We also prove the proposed labeled private set intersection (PSI) protocol is secure against semi-honest adversaries, and IXT is -semi-honest secure ( is leakage function). Finally, we do experiments to compare IXT with HXT. The experimental results show that the storage overhead and computation overhead of the search phase at the client-side in IXT is much lower than those in HXT. Meanwhile, the experimental results also show that IXT is scalable and can be applied to various sizes of datasets. 相似文献
65.
Zheng Jianbing Gao Ming Lim Ee-Peng Lo David Jin Cheqing Zhou Aoying 《Knowledge and Information Systems》2022,64(7):1967-1996
Knowledge and Information Systems - Network robustness measures how well network structure is strong and healthy when it is under attack, such as vertices joining and leaving. It has been widely... 相似文献
66.
Mobile Networks and Applications - Artificial fish swarm algorithm (AFS) is used in the field of function optimization problems widely. The traditional AFS algorithm has some problems such as long... 相似文献
67.
Wang Yong Wei Xian Tang Xuan Wu Jingjing Fang Jiangxiong 《Neural computing & applications》2022,34(7):5757-5769
Neural Computing and Applications - In recent years, RGB and thermal sensors are widely used. There is complementary information from these two types of sensors. A fundamental task which arises in... 相似文献
68.
Liang Likeng Hao Tianyong Zhan Choujun Qiu Hong Wang Fu Lee Yan Jun Weng Heng Qu Yingying 《Neural computing & applications》2022,34(19):16311-16324
Neural Computing and Applications - Medical concept normalization aims to construct a semantic mapping between mentions and concepts and to uniformly represent mentions that belong to the same... 相似文献
69.
Herein a useful methodology to synthesize the lead zirconate titanate (PZT) nanotubes via a dip-coating deposition process with anodic aluminum oxide (AAO) template is proposed. The nano-porous AAO templates were produced using a controlled two-step electrochemical anodization technique. The PZT/AAO composite was formed using the dip-coating wetting technique. The prepared PZT precursor solution was driven into the nanopore channels of AAO template under the driving force of capillary action, subsequently the sintering process of the as-filled templates was carefully tuned to obtain Pb(Zr0.52Ti0.48)O3 nanotubes of crystalline tetragonal phase with uniform pore size and ordered arrange. Fourier transform infrared spectroscopy (FTIR) results show that in the 1200–1900 cm−1 band, the composite structure of PZT/AAO has obvious absorption peaks at 1471.56 cm−1 and 1556.09 cm−1, the absorption intensity of the composite structure is about six times of pure AAO template. The unusual optical properties found in PZT/AAO composite will stimulate further theoretical and experimental interests in ferroelectric nanostructures. 相似文献
70.
Huibiao Zhu Jifeng He Jing Li Jonathan P. Bowen 《Innovations in Systems and Software Engineering》2011,7(3):209-224
Web services have become more and more important in these years, and BPEL4WS (BPEL) is a de facto standard for the web service
composition and orchestration. It contains several distinct features, including the scope-based compensation and fault handling
mechanism. We have considered the operational semantics and denotational semantics for BPEL, where a set of algebraic laws
can be achieved via these two models, respectively. In this paper, we consider the inverse work, deriving the operational
semantics and denotational semantics from algebraic semantics for BPEL. In our model, we introduce four types of typical programs,
by which every program can be expressed as the summation of these four types. Based on the algebraic semantics, the strategy
for deriving the operational semantics is provided and a transition system is derived by strict proof. This can be considered
as the soundness exploration for the operational semantics based on the algebraic semantics. Further, the equivalence between
the derivation strategy and the derived transition system is explored, which can be considered as the completeness of the
operational semantics. Finally, the derivation of the denotational semantics from algebraic semantics is explored, which can
support to reason about more program properties easily. 相似文献