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Spatio-temporal Characteristics of Area Coverage and Observation Geometry of the MISR Land-surface BRF Product: A Case Study of the Central Part of Northeast Asia 预览
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作者 LI Jian CHEN Shengbo +4 位作者 QIN Wenhan Mike MUREFU WANG Yufei YU Yan ZHEN Zhijun 《中国地理科学:英文版》 SCIE CSCD 2019年第4期679-688,共10页
The Multi-angle imaging spectroradiometer(MISR) land-surface(LS) bidirectional reflectance factor(BRF) product(MILS_BRF) has unique semi-simultaneous multi-angle sampling and global coverage. However, unlike on-satell... The Multi-angle imaging spectroradiometer(MISR) land-surface(LS) bidirectional reflectance factor(BRF) product(MILS_BRF) has unique semi-simultaneous multi-angle sampling and global coverage. However, unlike on-satellite observations, the spatio-temporal characteristics of MILS_BRF data have rarely been explicitly and comprehensively analysed. Results from 5-yr(2011–2015) of MILS_BRF dataset from a typical region in central Northeast Asia as the study area showed that the monthly area coverage as well as MILS_BRF data quantity varies significantly, from the highest in October(99.05%) through median in June/July(78.09%/75.21%) to lowest in January(18.97%), and a large data-vacant area exists in the study area during four consecutive winter months(December through March). The data-vacant area is mainly composed of crop lands and cropland/natural vegetation mosaic. The amount of data within the principal plane(PP)±30°(nPP) or cross PP ±30°(nCP), varies intra-annually with significant differences from different view zeniths or forward/backward scattering directions. For example, multiple off-nadir cameras have nPP but no nCP data for up to six months(September through February), with the opposite occurring in June and July. This study provides explicit and comprehensive information about the spatio-temporal characteristics of product coverage and observation geometry of MILS_BRF in the study area. Results provide required user reference information for MILS_BRF to evaluate performance of BRDF models or to compare with other satellite-derived BRF or albedo products. Comparing this final product to on-satellite observations, what was found here reveals a new perspective on product spatial coverage and observation geometry for multi-angle remote sensing. 展开更多
关键词 multi-angle remote sensing Multi-angle Imaging SPECTRORADIOMETER (MISR) bidirectional reflectance factor (BRF) SPATIO-TEMPORAL characteristics OBSERVATION GEOMETRY
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A comprehensive review on hybrid electric vehicles: architectures and components 预览
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作者 Krishna Veer Singh Hari Om Bansal Dheerendra Singh 《现代交通学报:英文版》 2019年第2期77-107,共31页
The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved fr... The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved from their inchoate state and are proving to be a promising solution to the serious existential problem posed to the planet earth. Not only do HEVs provide better fuel economy and lower emissions satisfying environmental legislations, but also they dampen the effect of rising fuel prices on consumers. HEVs combine the drive powers of an internal combustion engine and an electrical machine. The main components of HEVs are energy storage system, motor, bidirectional converter and maximum power point trackers (MPPT, in case of solar-powered HEVs). The performance of HEVs greatly depends on these components and its architecture. This paper presents an extensive review on essential components used in HEVs such as their architectures with advantages and disadvantages, choice of bidirectional converter to obtain high efficiency, combining ultracapacitor with battery to extend the battery life, traction motors’ role and their suitability for a particular application. Inclusion of photovoltaic cell in HEVs is a fairly new concept and has been discussed in detail. Various MPPT techniques used for solar-driven HEVs are also discussed in this paper with their suitability. 展开更多
关键词 HYBRID electric vehicle HYBRID energy storage system Architecture TRACTION motors BIDIRECTIONAL CONVERTER
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Ginseng and Angiogenesis:Promotion or Inhibition? 预览
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作者 Jun-Ju Zou Xiao-Tao Zhou +2 位作者 Wen-Yi Li Chao-Xi Zhu Yue-Rong Ma 《TMR食疗与健康管理》 2019年第1期22-29,共8页
Ginseng has a unique pharmacological activity,which can treat ischemic diseases through angiogenesis,and inhibit tumor growth and metastasis by anti-angiogenesis.Angiogenesis is a common target for tumors and ischemic... Ginseng has a unique pharmacological activity,which can treat ischemic diseases through angiogenesis,and inhibit tumor growth and metastasis by anti-angiogenesis.Angiogenesis is a common target for tumors and ischemic diseases.How could the ginseng regulateblood vessels in different diseases?Here,the mechanism of ginseng bidirectional regulation of angiogenesis in different pathological environments is reviewed,and the role of bidirectional regulation is elucidated. 展开更多
关键词 GINSENG TUMOR ANGIOGENESIS BIDIRECTIONAL regulation Research progress
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Modified Functional Projective Synchronization of the Unidirectional and Bidirectional Hybrid Connective Star Network with Coupling Time-Delay
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作者 LI Dekui 《武汉大学学报:自然科学英文版》 CAS CSCD 2019年第4期321-328,共8页
An unidirectional and bidirectional hybrid connective star network model with coupling time-delay is constructed in this paper. According to synchronization error systems, adaptive controllers for each node are struct... An unidirectional and bidirectional hybrid connective star network model with coupling time-delay is constructed in this paper. According to synchronization error systems, adaptive controllers for each node are structured by using the linear system stability method and the Lyapunov stability method. These adaptive controllers can realize the modified functional projective synchronization between each node of star network and an isolated node by argument and analysis. Finally, the corrective and effective of the adaptive controllers are illustrated by some numerical examples. 展开更多
关键词 star network UNIDIRECTIONAL and BIDIRECTIONAL HYBRID connection time-delay MODIFIED FUNCTIONAL projective synchronization
An Asymmetric Controlled Bidirectional Quantum State Transmission Protocol 预览
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作者 Yiru Sun Yuling Chen +1 位作者 Haseeb Ahmad Zhanhong Wei 《计算机、材料和连续体(英文)》 2019年第4期215-227,共13页
In this paper,we propose an asymmetric controlled bidirectional transmission protocol.In the protocol,by using the thirteen-qubit entangled state as the quantum channel,Alice can realize the transmission of a two-qubi... In this paper,we propose an asymmetric controlled bidirectional transmission protocol.In the protocol,by using the thirteen-qubit entangled state as the quantum channel,Alice can realize the transmission of a two-qubit equatorial state for Bob and Bob can transmit a four-qubit equatorial state for Alice under the control of Charlie.Firstly,we give the construction of the quantum channel,which can be done by performing several H and CNOT operations.Secondly,through implementing the appropriate measurements and the corresponding recovery operations,the desired states can be transmitted simultaneously,securely and deterministically.Finally,we analyze the performance of the protocol,including the efficiency,the necessary operations and the classical communication costs.And then,we describe some comparisons with other protocols.Since our protocol does not require auxiliary particles and additional operations,the classic communication costs less while achieving the multi-particle bidirectional transmission,so the overall performance of the protocol is better. 展开更多
关键词 CONTROLLED ASYMMETRIC bidirectional quantum state transmission remote state preparation
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跨网络用户动态双向身份准确认证仿真 预览
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作者 丁士杰 谢军 《计算机仿真》 北大核心 2019年第1期300-303,396共5页
实现跨网络用户动态双向身份准确认证是当前诸多领域重点关注的话题。针对当前认证方法存在耗时较长、系统资源占用率较高,且抗攻击性能较差的缺点,提出一种基于改进智能卡的跨网络用户动态双向身份认证方法,当计算机系统个人服务器收... 实现跨网络用户动态双向身份准确认证是当前诸多领域重点关注的话题。针对当前认证方法存在耗时较长、系统资源占用率较高,且抗攻击性能较差的缺点,提出一种基于改进智能卡的跨网络用户动态双向身份认证方法,当计算机系统个人服务器收到来自传感器节点发送的用户身份信息后,通过计算收到身份信息验证码与本身服务器存储的验证码对比验证用户身份的合法性,以及通过传感器节点与个人服务器共享密钥解密获得的用户身份信息当前时间戳与之前时间戳的比对即可初步实现跨网络用户双向身份认证。在初步认证基础上,在跨网络用户动态双向身份认证阶段加入计数器,用来统计跨网络用户身份认证阶段遭受的攻击情况,并通过对跨网络用户的标识符结构形式的合法验证和对计算机系统个人服务器在某时刻接收到身份信息时间戳的有效期进行核查,最终实现跨网络用户动态双向身份认证。仿真结果表明,上述方法具有耗时短、系统资源占用率低,且抗攻击性强的优点。 展开更多
关键词 跨网络用户 动态 双向 身份 准确认证
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在《核医学》教学过程中进行教与学双向评价的实践研究 预览
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作者 骆磊 朱郧鹤 《教育教学论坛》 2019年第11期151-152,共2页
《核医学》是医学院学生的必修课,作为一名高校医学教师,在教学过程中发现存在的问题并改进极为重要,双向评价作为一种有效的教学评价方法,能够有效发现问题并为教学改革政策的制定提供依据,同时它能够有效调动师生的主观能动性,不断提... 《核医学》是医学院学生的必修课,作为一名高校医学教师,在教学过程中发现存在的问题并改进极为重要,双向评价作为一种有效的教学评价方法,能够有效发现问题并为教学改革政策的制定提供依据,同时它能够有效调动师生的主观能动性,不断提升自我,达到指导及提高教学质量的目的。 展开更多
关键词 核医学 双向 研究
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Quasi-Z-Source Based Bidirectional DC-DC Converter and Its Control Strategy
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作者 Yuba Raj Kafle Saad Ul Hasan Graham E.Town 《中国电气工程学报(英文)》 2019年第1期1-9,共9页
This paper presents a quasi-Z-source based isolated bidirectional DC-DC converter(qZIBDC)for renewable energy applications.The converter utilizes a dual active bridge circuit with a quasi-Z-source network on both side... This paper presents a quasi-Z-source based isolated bidirectional DC-DC converter(qZIBDC)for renewable energy applications.The converter utilizes a dual active bridge circuit with a quasi-Z-source network on both sides,so the converter works as buck/boost converter from either side.It has a wider input/output voltage operating range,soft-switching capabilities without additional devices,and higher boost capability than a traditional dual active bridge circuit.Apart from that,shoot-through states are incorporated in its operating cycle to boost the input voltage resulting in high reliability of the proposed converter.Due to the symmetrical structure of the circuit,there is no defined high voltage or low voltage side as in traditional isolated bidirectional DC-DC converter.The operating principle and control strategy of the proposed converter are presented.Simulation and experimental results are provided to verify the effectiveness of the proposed converter topology and its control strategy. 展开更多
关键词 BIDIRECTIONAL DC-DC CONVERTER dual active bridge IMPEDANCE source quasi-Z-source DC-DC CONVERTER
Regenerative energy management of electric drive based on Lyapunov stability theorem 预览
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作者 Shahab SABZI Mehdi ASADI Hassan MOGHBELI 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第2期321-328,共8页
In recent years, urban rail systems have developed drastically. In these systems, when induction electrical machine suddenly brakes, a great package of energy is produced. This package of energy can be stored in energ... In recent years, urban rail systems have developed drastically. In these systems, when induction electrical machine suddenly brakes, a great package of energy is produced. This package of energy can be stored in energy storage devices such as battery, ultra-capacitor and flywheel. In this paper, an electrical topology is proposed to absorb regenerative braking energy and to store it in ultracapacitor and battery.Ultra-capacitor can deliver the stored energy to DC grid and charge the battery for auxiliary applications such as lighting and cooling systems The proposed system is modeled based on large signal averaged modeling, which leads to the simplicity of calculations. The control system is based on Lyapunov stability theorem which guarantees system stability. Also, an energy management algorithm is proposed to control energy under braking and steady-state conditions. Finally,the simulation results validate the effectiveness of the proposed control and energy management system. 展开更多
关键词 DC/DC CONVERTER LYAPUNOV stability BIDIRECTIONAL CONVERTER Energy management system(EMS) ULTRA-CAPACITOR Battery Switching function
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Exact Solutions to the Bidirectional SK-Ramani Equation 预览
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作者 Zou Jia-hui Wang Yun-hu Gao Wen-jie 《数学研究通讯:英文版》 CSCD 2019年第4期289-300,共12页
In this paper,the bidirectional SK-Ramani equation is investigated by means of the extended homoclinic test approach and Riemann theta function method,respectively.Based on the Hirota bilinear method,exact solutions i... In this paper,the bidirectional SK-Ramani equation is investigated by means of the extended homoclinic test approach and Riemann theta function method,respectively.Based on the Hirota bilinear method,exact solutions including one-soliton wave solution are obtained by using the extended homoclinic approach and one-periodic wave solution is constructed by using the Riemann theta function method.A limiting procedure is presented to analyze in detail the relations between the one periodic wave solution and one-soliton solution. 展开更多
关键词 HIROTA BILINEAR method BIDIRECTIONAL Sawada-Kotera EQUATION extended HOMOCLINIC test approach Riemann THETA function
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Bidirectional Optimization Coupled Ligh tweight Net works for Efficient and Robust Multi-Person 2D Pose Estimation
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作者 Shnai Li Zheng Fang +2 位作者 Wen-Feng Song Ai-Min Hao Hong Qin 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第3期522-536,共15页
For multi-person 2D pose estimation,current deep learning baised methods have exhibited impressive performance,but the trade-offs among efficiency,robustness,and accuracy in the existing approaches remain unavoidable.... For multi-person 2D pose estimation,current deep learning baised methods have exhibited impressive performance,but the trade-offs among efficiency,robustness,and accuracy in the existing approaches remain unavoidable.In principle,bottom-up methods are superior to top-down methods in efficiency,but they perform worse in accuracy.To make full use of their respective advantages,in this paper we design a novel bidirectional optimization coupled lightweight network(BOCLN)architecture for efficient,robust,and general-purpose multi-person 2D(2-dimensional)pose estimation from natural images.With the BOCLN framework,the bottom-up network focuses oil global features,while the top-down net work places emphasis on det ailed features.The entire framework shares global features along the bottom-up data stream,while the top-down data stream aims to accelerate the accurate pose estimation.In particular,to exploit the priors of human joints'relationship,we propose a probability limb heat map to represent the spatial context of the joints and guide the overall pose skeleton prediction,so that each person's pose estimation in cluttered scenes(involving crowd)could be as accurate and robust as possible.Therefore,benefiting from the novel BOCLN architecture,the tinie-consuming refinement procedure could be much simplified to an efficient lightweight network.Extensive experiments and evaluations on public benchmarks have confirmed that our new method is more efficient and robust,yet still attain competitive accuracy performance compared with the state-of-the-art methods.Our BOCLN shows even greater promise in online applications. 展开更多
关键词 BIDIRECTIONAL OPTIMIZATION computer vision deep learning probability LIMB heat map 2D multi-person POSE estimation
Evolutionary many objective optimization based on bidirectional decomposition 预览
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作者 LYU Chengzhong LI Weimin 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第2期319-326,共8页
The decomposition based approach decomposes a multi-objective problem into a series of single objective subproblems, which are optimized along contours towards the ideal point. But non-dominated solutions cannot sprea... The decomposition based approach decomposes a multi-objective problem into a series of single objective subproblems, which are optimized along contours towards the ideal point. But non-dominated solutions cannot spread uniformly, since the Pareto front shows different features, such as concave and convex. To improve the distribution uniformity of non-dominated solutions, a bidirectional decomposition based approach that constructs two search directions is proposed to provide a uniform distribution no matter what features problems have. Since two populations along two search directions show differently on diversity and convergence, an adaptive neighborhood selection approach is presented to choose suitable parents for the offspring generation. In order to avoid the problem of the shrinking search region caused by the close distance of the ideal and nadir points, a reference point update approach is presented. The performance of the proposed algorithm is validated with four state-of-the-art algorithms. Experimental results demonstrate the superiority of the proposed algorithm on all considered test problems. 展开更多
关键词 MANY objective optimization BIDIRECTIONAL DECOMPOSITION REFERENCE UPDATE EVOLUTIONARY algorithm
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一种基于滑模控制的双向DC/DC变换器的研究 预览
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作者 党乐 《软件》 2019年第6期212-218,共7页
论文针对航空静止变流器前端DC/DC级在大扰动下系统响应的快速性和鲁棒性,本文采用一种以变换器状态变量误差的线性组合的滑模算法为主控制器,以BUCK/BOOST双向DC-DC变换器为被控对象对该拓扑进行模态分析,其次对两种工作模态下分别进... 论文针对航空静止变流器前端DC/DC级在大扰动下系统响应的快速性和鲁棒性,本文采用一种以变换器状态变量误差的线性组合的滑模算法为主控制器,以BUCK/BOOST双向DC-DC变换器为被控对象对该拓扑进行模态分析,其次对两种工作模态下分别进行滑模面的设计及可达性条件的证明。在Matlab/Simulink环境下,进行仿真验证,与PI算法进行对比分析。仿真结果表明该滑模算法在大扰动下对系统响应的快速性及鲁邦性较PI算法有较大的改善和提高。 展开更多
关键词 鲁棒性 滑模 双向 变换器 可达性
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汉语中若干双向性的语义演变路径
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作者 金小栋 吴福祥 《汉语学报》 CSSCI 北大核心 2019年第4期40-49,95,96共12页
语义演变的方向不是绝对的。汉语中存在一些双向性的语义演变路径,它们主要见于某类词内部(如介词或副词内部)相近的语义之间的演变,也见于两类词之间双向的语法化中(如介词?动词、介词?连词)。某类词内部发生双向性的语义演变的条件是... 语义演变的方向不是绝对的。汉语中存在一些双向性的语义演变路径,它们主要见于某类词内部(如介词或副词内部)相近的语义之间的演变,也见于两类词之间双向的语法化中(如介词?动词、介词?连词)。某类词内部发生双向性的语义演变的条件是语义相近、相通,词类相同、虚实程度一样,并且句法环境相同。两类词之间双向性的语义演变,应与汉语的类型学特征有关。在双向性的语义演变路径中,某个方向的语义演变可能会更常见些,而这个方向的语义演变往往与隐喻等级序列一致。 展开更多
关键词 汉语语义演变 双向性
VCSEL wavelength reuse for intrinsically bidirectional data traffics in next generation GPONs
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作者 G.M.Isoe S.Wassin T.B.Gibbon 《光电子快报:英文版》 EI 2019年第5期360-362,共3页
An all-optical wavelength reuse technique employing cost effective power efficient vertical surface emitting laser(VCSEL) is proposed to address uplink data streaming from end-users by exploiting the same wavelength a... An all-optical wavelength reuse technique employing cost effective power efficient vertical surface emitting laser(VCSEL) is proposed to address uplink data streaming from end-users by exploiting the same wavelength assigned to them. A saturated optical erbium-doped optical fiber amplifier(EDFA) is adopted to erase a directly modulated 10 Gbit/s data from an incoming downstream wavelength. We show that with EDFA saturation, the extinction ration of the incoming wavelength is reduced to less than 1 d Bm, therefore allowing for wavelength re-modulation. A receiver sensitivity of -19.65 d Bm and -17.86 d Bm is attained for downstream and upstream data signals respectively. A total of 24.7 km single mode fibre transmission is attained experimentally. This technique opens new perspectives towards development of efficient spectrum utilization for application in wavelength flexible optical networks with non-static flex-spectrum grids. 展开更多
关键词 VCSEL ERBIUM-DOPED optical fiber amplifier(EDFA) intrinsically BIDIRECTIONAL
Medical Knowledge Extraction and Analysis from Electronic Medical Records Using Deep Learning 预览
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作者 Peilin Li Zhenming Yuan +2 位作者 Wenbo Tu Kai Yu Dongxin Lu 《中国医学科学杂志:英文版》 CAS CSCD 2019年第2期133-139,共7页
Objectives Medical knowledge extraction (MKE) plays a key role in natural language processing (NLP) research in electronic medical records (EMR),which are the important digital carriers for recording medical activitie... Objectives Medical knowledge extraction (MKE) plays a key role in natural language processing (NLP) research in electronic medical records (EMR),which are the important digital carriers for recording medical activities of patients.Named entity recognition (NER) and medical relation extraction (MRE) are two basic tasks of MKE.This study aims to improve the recognition accuracy of these two tasks by exploring deep learning methods.Methods This study discussed and built two application scenes of bidirectional long short-term memory combined conditional random field (BiLSTM-CRF) model for NER and MRE tasks.In the data preprocessing of both tasks,a GloVe word embedding model was used to vectorize words.In the NER task,a sequence labeling strategy was used to classify each word tag by the joint probability distribution through the CRF layer.In the MRE task,the medical entity relation category was predicted by transforming the classification problem of a single entity into a sequence classification problem and linking the feature combinations between entities also through the CRF layer.Results Through the validation on the I2B2 2010 public dataset,the BiLSTM-CRF models built in this study got much better results than the baseline methods in the two tasks,where the F1-measure was up to 0.88 in NER task and 0.78 in MRE task.Moreover,the model converged faster and avoided problems such as overfitting.Conclusion This study proved the good performance of deep learning on medical knowledge extraction.It also verified the feasibility of the BiLSTM-CRF model in different application scenarios,laying the foundation for the subsequent work in the EMR field. 展开更多
关键词 MEDICAL knowledge EXTRACTION electronic MEDICAL record named ENTITY recognition MEDICAL relation EXTRACTION deep learning BIDIRECTIONAL long SHORT-TERM memory CONDITIONAL random field
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Relation Extraction Based on Dual Attention Mechanism 预览
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作者 Xue Li Yuan Rao +1 位作者 Long Sun Yi Lu 《国际计算机前沿大会会议论文集》 2019年第1期354-356,共3页
The traditional deep learning model has problems that the longdistance dependent information cannot be learned, and the correlation between the input and output of the model is not considered. And the information proc... The traditional deep learning model has problems that the longdistance dependent information cannot be learned, and the correlation between the input and output of the model is not considered. And the information processing on the sentence set is still insufficient. Aiming at the above problems, a relation extraction method combining bidirectional GRU network and multiattention mechanism is proposed. The word-level attention mechanism was used to extract the word-level features from the sentence, and the sentence-level attention mechanism was used to focus on the characteristics of sentence sets. The experimental verification in the NYT dataset was conducted. The experimental results show that the proposed method can effectively improve the F1 value of the relationship extraction. 展开更多
关键词 BIDIRECTIONAL GRU Multi-attention RELATION extraction
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层次化水下通信网络移动节点双向认证系统 预览
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作者 陈伟 《舰船科学技术》 北大核心 2019年第12期136-138,共3页
现有的层次化舰船网络移动节点双向认证系统存在着认证效率低的弊端,为此提出层次化舰船网络移动节点双向认证系统设计研究。层次化舰船网络移动节点双向认证系统沿用现有系统的硬件设备,主要对软件进行设计。层次化舰船网络移动节点双... 现有的层次化舰船网络移动节点双向认证系统存在着认证效率低的弊端,为此提出层次化舰船网络移动节点双向认证系统设计研究。层次化舰船网络移动节点双向认证系统沿用现有系统的硬件设备,主要对软件进行设计。层次化舰船网络移动节点双向认证系统软件设计主要包括注册模块、登录模块与认证模块,通过软件设计的应用实现了层次化舰船网络移动节点双向认证系统的运行。采用移动节点单向认证系统、移动节点有限元认证系统与设计的移动节点双向认证系统进行对比实验分析,相较于其他2种认证系统来说,设计的层次化舰船网络移动节点双向认证系统运算量与运算时间较少,充分说明设计的层次化舰船网络移动节点双向认证系统具备更高的认证效率。 展开更多
关键词 层次化舰船网络 移动节点 双向 认证
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Image-based appearance acquisition of effect coatings
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作者 Jirí Filip Radomír Vávra 《计算可视媒体(英文版)》 CSCD 2019年第1期73-89,共17页
Paint manufacturers strive to introduce unique visual effects to coatings in order to visually communicate functional properties of products using value-added, customized design. However, these effects often feature c... Paint manufacturers strive to introduce unique visual effects to coatings in order to visually communicate functional properties of products using value-added, customized design. However, these effects often feature complex, angularly dependent, spatiallyvarying behavior, thus representing a challenge in digital reproduction. In this paper we analyze several approaches to capturing spatially-varying appearances of effect coatings. We compare a baseline approach based on a bidirectional texture function(BTF) with four variants of half-difference parameterization. Through a psychophysical study, we determine minimal sampling along individual dimensions of this parameterization.We conclude that, compared to BTF, bivariate representations better preserve visual fidelity of effect coatings, better characterizing near-specular behavior and significantly the restricting number of images which must be captured. 展开更多
关键词 EFFECT COATINGS measurement BIDIRECTIONAL texture function(BTF) APPEARANCE PSYCHOPHYSICAL experiment
谈顶升在已有建筑双向纠倾中的应用 预览
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作者 李孟琳 《林业科技情报》 2019年第1期84-87,共4页
以镇江某项目的顶升纠倾为例,介绍了顶升纠倾的基本原理。并结合该工程现场施工资料及后期的裂缝、沉降观测报告,表明采用先基础加固后双向调整顶升纠倾不仅能够满足建筑物的使用性、安全性,而且具有良好的社会效益与经济效益。
关键词 双向 顶升纠倾 加固 锚杆静压桩
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