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Three-dimensional visualization of the functional fascicular groups of a long-segment peripheral nerve 被引量:3
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作者 Jian Qi Wei-Ya Wang +7 位作者 Ying-Chun Zhong Jia-Ming Zhou Peng Luo Ping Tang Cai-Feng He Shuang Zhu Xiao-Lin Liu Yi Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第8期1465-1470,共6页
The three-dimensional(3D) visualization of the functional bundles in the peripheral nerve provides direct and detailed intraneural spatial information. It is useful for selecting suitable surgical methods to repair ... The three-dimensional(3D) visualization of the functional bundles in the peripheral nerve provides direct and detailed intraneural spatial information. It is useful for selecting suitable surgical methods to repair nerve defects and in optimizing the construction of tissue-engineered nerve grafts. However, there remain major technical hurdles in obtaining, registering and interpreting 2D images, as well as in establishing 3D models. Moreover, the 3D models are plagued by poor accuracy and lack of detail and cannot completely reflect the stereoscopic microstructure inside the nerve. To explore and help resolve these key technical problems of 3D reconstruction, in the present study, we designed a novel method based on re-imaging techniques and computer image layer processing technology. A 20-cm ulnar nerve segment from the upper arm of a fresh adult cadaver was used for acetylcholinesterase(ACh E) staining. Then, 2D panoramic images were obtained before and after ACh E staining under the stereomicroscope. Using layer processing techniques in Photoshop, a space transformation method was used to fulfill automatic registration. The contours were outlined, and the 3D rendering of functional fascicular groups in the long-segment ulnar nerve was performed with Amira 4.1 software. The re-imaging technique based on layer processing in Photoshop produced an image that was detailed and accurate. The merging of images was accurate, and the whole procedure was simple and fast. The least square support vector machine was accurate, with an error rate of only 8.25%. The 3D reconstruction directly revealed changes in the fusion of different nerve functional fascicular groups. In conclusion. The technique is fast with satisfactory visual reconstruction. 展开更多
关键词 nerve regeneration peripheral nerve ulnar nerve three-dimensional reconstruction functional fascicular group REGISTRATION segmentation locating spots auto-registration ACETYLCHOLINESTERASE neural regeneration
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Three-dimensionally ordered macroporous cross-linked polystyrene incorporating functional group via hydrophilic spacer arm 被引量:1
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作者 Li Xia Yuan Xiao Mei Wang Xu Zhang Pan Ge Liu Wei Dong Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1493-1496,共4页
A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.Th... A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.The 3DOM CLPS with pore size 865 nm was prepared by sacrifice template method.The hydrophilic spacer arm(polyethylene glycol,molecular weight is 600) was grafted to the 3DOM CLPS via nucleophilic substitution reaction.The other side of active hydroxyl can be further converted into a lot of other functional groups.In this report,the chelating ligand 2-mercaptobenzothiazole(MBZ) group was introduced on the end of the PGE chain to evidence the versatile functionalization approach.The functionalized ordered macroporous materials were characterized by FT-IR,element analyzer,SEM.The results reveal that the pores were successfully bonded with 2-mercaptobenzothiazole groups via hydrophilic spacer arms and the original morphology of ordered macroporous materials were remained after functionalization.The MBZ group density is 0.052 mmol/m^2.The functionalized 3DOM CLPS are expected to application as heavy metal ions adsorbent. 展开更多
关键词 three-dimensionally ordered macroporous polymer FUNCTIONALIZATION Hydrophilic space arm Heterocyclic functional group
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MESHLESS ANALYSIS FOR THREE-DIMENSIONAL ELASTICITY WITH SINGULAR HYBRID BOUNDARY NODE METHOD 被引量:1
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作者 苗雨 王元汉 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第5期673-681,共9页
The singular hybrid boundary node method (SHBNM) is proposed for solving three-dimensional problems in linear elasticity. The SHBNM represents a coupling between the hybrid displacement variational formulations and ... The singular hybrid boundary node method (SHBNM) is proposed for solving three-dimensional problems in linear elasticity. The SHBNM represents a coupling between the hybrid displacement variational formulations and moving least squares (MLS) approximation. The main idea is to reduce the dimensionality of the former and keep the meshless advantage of the later. The rigid movement method was employed to solve the hyper-singular integrations. The 'boundary layer effect', which is the main drawback of the original Hybrid BNM, was overcome by an adaptive integration scheme. The source points of the fundamental solution were arranged directly on the boundary. Thus the uncertain scale factor taken in the regular hybrid boundary node method (RHBNM) can be avoided. Numerical examples for some 3D elastic problems were given to show the characteristics. The computation results obtained by the present method are in excellent agreement with the analytical solution. The parameters that influence the performance of this method were studied through the numerical examples. 展开更多
关键词 three-dimensional elasticity moving least squares meshless method modified variational principle singular hybrid boundary node method
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Using Three-Dimensional Lorenz Scatter Plots to Detect Patients with Atrioventricular Node Double Path Caused by Interpolated Ventricular Premature Systoles: A Case Study 被引量:1
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作者 Li Jingxiu Zhang Fujun +1 位作者 Wei Xijin Peng Ding 《Cardiovascular Innovations and Applications》 2021年第2期301-306,共6页
A series of related electrophysiology phenomena can be caused by the occurrence of interpolated ventricular premature contraction.In our recent three-dimensional Lorenz R-R scatter plot research,we found that atrioven... A series of related electrophysiology phenomena can be caused by the occurrence of interpolated ventricular premature contraction.In our recent three-dimensional Lorenz R-R scatter plot research,we found that atrioventricular node double path caused by interpolated ventricular premature contraction imprints a specifi c pattern on three-dimensional Lorenz plots generated from 24-hour Holter recordings.We found two independent subclusters separated from the interpolated premature beat precluster,the interpolated premature beat cluster,and the interpolated premature beat postcluster,respectively.Combined with use of the trajectory tracking function and the leap phenomenon,our results reveal the presence of the atrioventricular node double conduction path. 展开更多
关键词 three-dimensional Lorenz scatter plots interpolated ventricular premature contractions atrioventricular node double conduction path
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Investigation of high-mobility group box 1 variants with lymph node status and colorectal cancer risk
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作者 Xin Liu Sheng Zhang +4 位作者 Hao Qiu Zhi-Qiang Xie Wei-Feng Tang Yu Chen Xi Wei 《World Journal of Gastrointestinal Oncology》 2025年第4期67-80,共14页
BACKGROUND Accumulating studies indicated that maintain nuclei homeostasis was deemed to the protective factors for the occurrence of cancer.Thus,high-mobility group box 1(HMGB1)might influence the risk and poorer pro... BACKGROUND Accumulating studies indicated that maintain nuclei homeostasis was deemed to the protective factors for the occurrence of cancer.Thus,high-mobility group box 1(HMGB1)might influence the risk and poorer prognoses of colorectal cancer(CRC).AIM This study was designed to investigate whether HMGB1 polymorphisms influence the risk and lymph node metastasis(LNM)of CRC.METHODS Firstly,we designed an investigation with 1003 CRC patients and 1303 cancer-free controls to observe whether HMGB1 rs1412125 T>C and rs1045411 C>T SNPs could influence the risk of cancer.Subsequently,we carried out a correlation-analysis to assess whether these SNPs could alter the risk of LNM.RESULTS The current investigation suggested a relationship of HMGB1 rs1412125 SNP with the increased susceptibility of CRC.In a subgroup analysis,our findings suggested that this SNP could enhance an occurrence of CRC in≥61 years,non-drinker and body mass index<24 kg/m2 subgroups.However,we found that there was null association between HMGB1 rs1412125 SNP and LNM,even in different CRC region.These observations were confirmed by calculating the power value(more than 0.8).The association of HMGB1 rs1045411 C>T SNP with CRC risk and LNM was not found in any compare.CONCLUSION This study highlights a possible association between HMGB1 rs1412125 polymorphism and the increased risk of CRC.In the future,more studies should be conducted to explore HMGB1 rs1412125 polymorphism in relation to CRC development. 展开更多
关键词 High-mobility group box 1 Colorectal cancer POLYMORPHISM Immune Lymph nodes metastasis
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Three-dimensional Covalent Organic Frameworks as Host Materials for Lithium-Sulfur Batteries 被引量:3
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作者 Zhen Li Hang-Yu Zhou +4 位作者 Fu-Lai Zhao Tian-Xiong Wang Xuesong Ding Bao-Hang Han Wei Feng 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第5期550-557,I0008,共9页
Two reported three-dimensional covalent organic frameworks(3D-COFs),COF-300 and COF-301,which have hierarchical porous structures and large pore volumes,were synthesized and employed as host materials for lithium-sulf... Two reported three-dimensional covalent organic frameworks(3D-COFs),COF-300 and COF-301,which have hierarchical porous structures and large pore volumes,were synthesized and employed as host materials for lithium-sulfur batteries.Owing to possessing excellent porosities as well as abundant hydroxyl groups in the pore walls,COF-301 can not only trap lithium polysulfides(PSs)via physical adsorption inside the pores,but also capture PSs by chemical interactions to relieve the shuttle effect.Interestingly,it is the first time that 3D-COFs were utilized as host materials for lithium-sulfur batteries as well as hydroxyl groups were introduced into COFs for improving the battery performance.As a result,COF-301@S as cathode material could reserve the capacity of 411.6 mA·h·g^-1 after 500 cycles with only 0.081%fading per cycle at 0.5 C,exhibiting better battery performance compared with COF-300@S.This study not only expands the applications of 3D-COFs but also provides a new route for designing lithium-sulfur batteries. 展开更多
关键词 three-dimensional covalent organic framework Flost material Lithium-sulfur battery Flydroxyl group Chemical interaction
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AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE THREE-DIMENSIONAL FLOW IN CASCADES;PART I—TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES 被引量:2
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作者 康顺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第5期489-495,共7页
Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rul... Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rules are (1) for a rotor cascade without shroud band, the total number of nodal points equals that the saddle points on the skin-friction line vector fields in eachpitch range; (2) for an annular or straight cascade with no-clearances at blade ends, the total number of saddle points is two more than that of nodal points on the skin-friction line fields in a pitch; (3) the total number of saddles in the secondary flow fields on cross-sections in cascade is one less than that of nodes; (4) in the section streamline vector fields on a meridian surface penetrating a flow passage, and on leading and trailing edge sections, the total number of nodes is equal to that of saddles; (5) on the streamline vector fields of a blade-to-blade surface, the total number of nodes is one less than that of saddles. 展开更多
关键词 node TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE three-dimensional FLOW IN CASCADES PART I
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THE RELATIONSHIP BETWEEN THE INVASION OF PARAPHARYNGEAL SPACES AND THE INVOLVEMENT OF CERVICAL NODES AND POSTERIOR GROUP CRANIAL NERVES IN NASOPHARYNGEAL CARCINOMA 被引量:1
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作者 卢泰祥 张恩罴 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1992年第1期65-70,共6页
Two hundred cates of nasopharyngeal carcinoma (NPC) admitted to this department from Feb. 1985 to May. 1988 were analysed according to the CT scanning and clinical findings of the primary lesions prior to radiotherapy... Two hundred cates of nasopharyngeal carcinoma (NPC) admitted to this department from Feb. 1985 to May. 1988 were analysed according to the CT scanning and clinical findings of the primary lesions prior to radiotherapy. The results showed that involvement of parapharyngeal space was very common in NPC, about 80% (160/200 cases) ; particularly unilateral or bilateral retro-styloid spaces, about 69.5% (139/200 cases). It was proposed that patients with NPC had a high Incidence of ipsilateral cervical node metastasis. Contralateral cervical node metastasis was rare. The development of cervical node metastasto in NPC has two modes: one Is direct Infiltration of the retro-stylold space by the lesion; the other Is along the nasopharyngeal lymphatic rete. The data also showed that patients with NPC who presented symptoms of Ⅸ- Ⅲ cranial nerve paralyses always had ipsilateral or bilateral retro- styloid space Infiltrations. 展开更多
关键词 NPC THE RELATIONSHIP BETWEEN THE INVASION OF PARAPHARYNGEAL SPACES AND THE INVOLVEMENT OF CERVICAL nodeS AND POSTERIOR group CRANIAL NERVES IN NASOPHARYNGEAL CARCINOMA line
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Soliton solutions,travelling wave solutions and conserved quantities for a three-dimensional soliton equation in plasma physics
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作者 Chaudry Masood Khalique Oke Davies Adeyemo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第12期25-57,共33页
Many physical systems can be successfully modelled using equations that admit the soliton solutions.In addition,equations with soliton solutions have a significant mathematical structure.In this paper,we study and ana... Many physical systems can be successfully modelled using equations that admit the soliton solutions.In addition,equations with soliton solutions have a significant mathematical structure.In this paper,we study and analyze a three-dimensional soliton equation,which has applications in plasma physics and other nonlinear sciences such as fluid mechanics,atomic physics,biophysics,nonlinear optics,classical and quantum fields theories.Indeed,solitons and solitary waves have been observed in numerous situations and often dominate long-time behaviour.We perform symmetry reductions of the equation via the use of Lie group theory and then obtain analytic solutions through this technique for the very first time.Direct integration of the resulting ordinary differential equation is done which gives new analytic travelling wave solutions that consist of rational function,elliptic functions,elementary trigonometric and hyperbolic functions solutions of the equation.Besides,various solitonic solutions are secured with the use of a polynomial complete discriminant system and elementary integral technique.These solutions comprise dark soliton,doubly-periodic soliton,trigonometric soliton,explosive/blowup and singular solitons.We further exhibit the dynamics of the solutions with pictorial representations and discuss them.In conclusion,we contemplate conserved quantities for the equation under study via the standard multiplier approach in conjunction with the homotopy integral formula.We state here categorically and emphatically that all results found in this study as far as we know have not been earlier obtained and so are new. 展开更多
关键词 three-dimensional soliton equation Lie group theory conserved quantities soliton and exact travelling wave solutions PHYSICS
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Role of 3DCT in laparoscopic total gastrectomy with spleen-preserving splenic lymph node dissection 被引量:22
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作者 Jia-Bin Wang Chang-Ming Huang +4 位作者 Chao-Hui Zheng Ping Li Jian-Wei Xie Jian-Xian Lin Jun Lu 《World Journal of Gastroenterology》 SCIE CAS 2014年第16期4797-4805,共9页
AIM: To investigate whether computed tomography with 3D imaging (3DCT) can reduce the risks associated with laparoscopic surgery.
关键词 Stomach neoplasms Spleen preservation LAPAROSCOPY Lymph node dissection Computed tomography angiography with three-dimensional imaging
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基于sparse group Lasso方法的脑功能超网络构建与特征融合分析 被引量:7
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作者 李瑶 赵云芃 +3 位作者 李欣芸 刘志芬 陈俊杰 郭浩 《计算机应用》 CSCD 北大核心 2020年第1期62-70,共9页
功能超网络广泛地应用于脑疾病诊断和分类研究中,而现有的关于超网络创建的研究缺乏解释分组效应的能力或者仅考虑到脑区间组级的信息,这样构建的脑功能超网络会丢失一些有用的连接或包含一些虚假的信息,因此,考虑到脑区间的组结构问题... 功能超网络广泛地应用于脑疾病诊断和分类研究中,而现有的关于超网络创建的研究缺乏解释分组效应的能力或者仅考虑到脑区间组级的信息,这样构建的脑功能超网络会丢失一些有用的连接或包含一些虚假的信息,因此,考虑到脑区间的组结构问题,引入sparse group Lasso(sgLasso)方法进一步改善超网络的创建。首先,利用sgLasso方法进行超网络创建;然后,引入两组超网络特有的属性指标进行特征提取以及特征选择,这些指标分别是基于单一节点的聚类系数和基于一对节点的聚类系数;最后,将特征选择后得到的两组有显著差异的特征通过多核学习进行特征融合和分类。实验结果表明,所提方法经过多特征融合取得了87.88%的分类准确率。该结果表明为了改善脑功能超网络的创建,需要考虑到组信息,但不能逼迫使用整组信息,可以适当地对组结构进行扩展。 展开更多
关键词 超网络 SPARSE group Lasso 基于一对节点的聚类系数 多核学习 抑郁症 机器学习
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On-demand multicast routing protocol based on node classification in MANET 被引量:2
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作者 邓霞 孙利民 +2 位作者 王建新 罗玉宏 陈建二 《Journal of Central South University of Technology》 EI 2006年第2期190-195,共6页
An improved on-demand multicast routing protocol(ODMRP), node classification on-demand multicast routing protocol(NC-ODMRP), which is based on node classification in mobile ad hoc networks was proposed. NC-ODMRP class... An improved on-demand multicast routing protocol(ODMRP), node classification on-demand multicast routing protocol(NC-ODMRP), which is based on node classification in mobile ad hoc networks was proposed. NC-ODMRP classifies nodes into such three categories as ordinary node, forwarding group(FG) node, neighbor node of FG node according to their history forwarding information. The categories are distinguished with different weights by a weight table in the nodes. NC-ODMRP chooses the node with the highest weight as an FG node during the setup of forwarding group, which reduces a lot of redundant FG nodes by sharing more FG nodes between different sender and receiver pairs. The simulation results show that NC-ODMRP can reduce more than 20% FG number of ODMRP, thus enhances nearly 14% data forwarding efficiency and 12% energy consumption efficiency when the number of multicast senders is more than 5. 展开更多
关键词 mobile ad hoc networks MULTICAST forwarding group(FG) node classification
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A Framework for Exploring the Dynamics of Autonomous Work Groups in Manufacturing Organizations
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作者 Joseph W K Chan W B Lee 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期211-212,共2页
Nowadays, new paradigm of enterprise organization i s constantly changing due to the emergence of the global marketplace, the rise of information technology, and the emphasis of the social developments. This re quires... Nowadays, new paradigm of enterprise organization i s constantly changing due to the emergence of the global marketplace, the rise of information technology, and the emphasis of the social developments. This re quires a more flexible form of organization that are more adaptable to rapid cha nges in business environment such as autonomous work groups (AWGs) in order to achieve higher productivity and effectiveness. AWGs are work units responsib le for the production of goods and the provision of services. They involve team members in making decisions that are traditionally the responsibility of the sup ervisors and managers (Cohen & Bailey, 1997). Team members of AWGs are allowed t o self-regulate their behavior on jobs such as task assignments, methods for ca rrying out the work, and scheduling of activities etc. (Cohen & Ledford, 1994). For example, Motorola achieved a high organizational performance due to the succ essful implementation of AWGs in quality management (Piczak & Hauser, 1996). Xer ox also reported their operational successes based on the team-oriented work gr oups (Wageman, 1997). In recent years many organizations have replaced the traditional layers of manag ement with autonomous team-based work arrangements. Surveys indicated that the adoption of AWGs has soared in responding to the competitive business challenges . Many enterprises are making a deliberate effort to use AWGs to carry out work and operational processes as an alternative for hierarchical approaches (Lawler et al., 1995). There is a growing body of evidence that AWGs are more effective than traditionally managed groups and they contributes to organizational perform ance, such as improvement in operational performance, productivity, quality, cos t savings, employee attitude and behavior, and employee satisfaction (e.g. Pears on, 1992; Cohen & Ledford, 1994; Seers et al. 1995). Given the complexity and cognitive nature of team-based organizations, the mech anisms that the enterprises use in the development of the increasingly sophistic ated models, which can contribute to the effective functioning of AWGs, are extr emely important. The process of developing effective AWGs enables enterprises to inherent built-in intelligence of the organizations so that they will be more able to accommodate to external pressures and changes. The context of this paper is the construction of a dynamics framework and a stra tegic path for autonomous work groups in the technology-oriented manufacturing organization re-design. The framework is a conceptual one drawn from the litera ture survey. The importance of studying autonomous work groups for today’s manuf acturing organizations is claimed. Based on the General System Theory (GST), the characterization of AWGs is addressed. Three-dimensional domains such as t echnical content, service content, and relationship content are identified. A st rategic path is proposed to guide the organizations how the development of AWGs progresses at different levels of maturity that are associated with organization al effectiveness and performance. The utility of the model for AWGs is expected to provide technology-oriented organizations with a strategic path to achieve h igher organizational performance. 展开更多
关键词 autonomous work group three-dimensional dynamic s model general systems theory EFFECTIVENESS maturity level
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Clinical signification of high-mobility group box 1protein(HMGB1) expression in infiltrating ductalcarcinoma breast tissue
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作者 Baoping Chang Xiao Wang +5 位作者 Songsou Gao Bianfeng Zhao Wanli Wang Shaohua Yang Qian Chu Shiying Yu 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第5期215-219,共5页
Objective: Exploring the clinical signification of high-mobility group box 1 protein(HMGB1) expression in infiltrating ductal carcinoma(IDC) breast tissue. Methods: The expression of HMGB1 protein in IDC breast tissue... Objective: Exploring the clinical signification of high-mobility group box 1 protein(HMGB1) expression in infiltrating ductal carcinoma(IDC) breast tissue. Methods: The expression of HMGB1 protein in IDC breast tissue was detected by immunohistochemistry, and the relations among size of tumour, lymph node metastasis, clinical staging, estrogen receptor(ER), progesterone receptor(PR) and human epidermal growth factor receptor 2(HER-2) were also analyzed. Results: Fortysix cases out of 60 cases of IDC breast tissue showed positive or strong positive HMGB1 expression(76.67%), statistical significance was observed between HMGB1 expression with clinical staging(P < 0.01), lymph node metastasis(P < 0.01), breast cancer ER(P < 0.05) and HER-2(P < 0.05), however same conclusion can not be drawn between HMGB1 with either size of tumour or PR expression(P > 0.05) in IDC breast tissue. Spearman analysis showed negative correlation between HMGB1 expression and ER, and positive correlation between HMGB1 expression and clinical staging, lymph node metastasis together with HER-2. Conclusion: It's promising that HMGB1 expression in IDC tissue can be one of biological indicators of poor prognosis. 展开更多
关键词 infiltrating ductal carcinoma (IDC) high-mobility group box 1 protein (HMGB1) clinical staging lymph node estrogen receptor (ER) human epidermal growth factor receptor 2 (HER-2)
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社交媒体群体极化背景下中介人识别及其信息传播效率影响研究 被引量:2
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作者 戴建华 程欣怡 《情报理论与实践》 北大核心 2025年第4期118-124,共7页
[目的/意义]旨在运用网络分析的方法,研究社交媒体上的信息中介节点在弥合不同声音、交换不同观点方面发挥的关键作用。[方法/过程]通过分析社交媒体应用平台——“推特”上交流互动的实例数据,在可视化两方政党之间的意见极化现象的基... [目的/意义]旨在运用网络分析的方法,研究社交媒体上的信息中介节点在弥合不同声音、交换不同观点方面发挥的关键作用。[方法/过程]通过分析社交媒体应用平台——“推特”上交流互动的实例数据,在可视化两方政党之间的意见极化现象的基础上,提出了改进的中介中心性指标算法,将中介中心性指标值高的节点视为极化网络中的隐性关键中介节点,通过SI模型仿真模拟信息在社交极化网络中的扩散过程,探究了关键的中介节点在信息传播中呈现的重要作用。[结果/结论]结果显示,当中介节点被移除时,极化网络中信息传播速度显著下降,特别是在跨社区的传播中,传播范围和效率均受到了严重影响。这表明中介节点作为连接不同社区的桥梁节点,通过填补社区间的结构洞,极大地提升了信息的跨社区传播效率。 展开更多
关键词 群体极化 结构洞 中介节点 SI传染病模型 信息扩散
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引入有向联合图的谣言传播中关键节点群组检测研究
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作者 吴树芳 常欢 +1 位作者 刘畅 张雄涛 《现代情报》 北大核心 2025年第9期97-107,共11页
[目的/意义]网络谣言传播中关键节点的检测对维护网络空间清朗、促进社会稳定具有重要意义。针对当前关键节点检测研究忽略节点在多条谣言传播过程中的作用,从而导致关键节点误检或漏检的问题,提出引入有向联合图的谣言传播中关键节点... [目的/意义]网络谣言传播中关键节点的检测对维护网络空间清朗、促进社会稳定具有重要意义。针对当前关键节点检测研究忽略节点在多条谣言传播过程中的作用,从而导致关键节点误检或漏检的问题,提出引入有向联合图的谣言传播中关键节点群组检测方法。[方法/过程]首先,通过整合多条谣言传播树,构建有向谣言传播联合图,获得涵盖多条谣言传播的网络结构图。其次,在该图中挖掘出节点发布谣言数量、传播谣言数量以及影响力三维指标,实现对图中节点重要性的量化。最后,通过计算依据重要性排序的节点谣言信息覆盖率,检测出谣言传播中的关键节点群组。[结果/结论]实证研究在公开数据集上展开,通过对数据集进行标注和可视化处理,构建了基于数据集的有向谣言传播联合图。实验结果显示:与已有方法相比,所提方法在准确率、召回率和F1值上均有所提高。 展开更多
关键词 谣言传播 有向谣言传播联合图 关键节点群组 谣言信息覆盖率 检测
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基于“云-群-端”架构分布式光伏群调群控策略研究 被引量:1
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作者 张琳娟 张平 +3 位作者 卢丹 韩军伟 李景丽 袁豪 《电测与仪表》 北大核心 2025年第8期142-153,共12页
针对大规模分布式电源并网引起的电压波动、潮流返送等问题,开展分布式电源的群调群控策略研究是构建新型电力系统保障其安全稳定运行的重要基础工作。文中分析了分布式光伏并网时的可观可控性,提出基于“云-群-端”架构,并以集群为中... 针对大规模分布式电源并网引起的电压波动、潮流返送等问题,开展分布式电源的群调群控策略研究是构建新型电力系统保障其安全稳定运行的重要基础工作。文中分析了分布式光伏并网时的可观可控性,提出基于“云-群-端”架构,并以集群为中间层的分布式光伏分层调控策略;其中云层调控中心整合并分析各集群的上传运行数据,选取能灵敏反映集群电压变化的主导节点,以整个区域节点电压不越限、系统的网损最小为目标,构建群间协调优化策略;集群层控制平台分析终端设备层上传的光伏电站运行数据、负荷信息以及无功补偿装置监测数据,以实现集群内部节点电压安全运行、集群网损最小以及分布式光伏的最大就地消纳为目标,构建群内自治优化调控策略。最后采用所提出的分布式电源群调群控优化策略对改进的IEEE 33节点系统节点电压安全运行、越限等多种典型场景进行优化调控,结果表明所提控制策略可有效解决电压越限等问题,并能减小节点电压偏差与系统网损,保障系统安全经济运行。 展开更多
关键词 分布式光伏 群调群控 群间协调 群内自治 节点电压
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基于动态图表示学习的轻量化节点分类方法
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作者 闫钦与 颜靖华 +1 位作者 卜凡亮 王宇哲 《现代电子技术》 北大核心 2025年第18期1-8,共8页
动态图节点分类是图表示学习领域的经典下游任务,旨在通过动态图中已有信息预测未标记节点所属类别。然而,现有动态图节点分类方法普遍存在模型规模较大、结构复杂导致的计算压力问题。为解决该问题,提出一种基于动态图表示学习的轻量... 动态图节点分类是图表示学习领域的经典下游任务,旨在通过动态图中已有信息预测未标记节点所属类别。然而,现有动态图节点分类方法普遍存在模型规模较大、结构复杂导致的计算压力问题。为解决该问题,提出一种基于动态图表示学习的轻量化节点分类方法(LNDG)。该方法采用图编码器对动态图节点、链路和时间信息进行编码;并引入一个创新的GAM模块,利用分组查询注意力(GQA)机制和MLP-Mixer方法进一步学习时间和空间维度的特征表示,实现对动态图特征的完整捕捉。在3个公开的经典数据集上的实验结果表明,LNDG方法整体的参数量仅为0.70 MB,相较于基线模型AUC值更优,具有轻量化和高效性的优势。所提方法在整体规模和最终效果方面达到了较好的平衡,在动态图节点分类任务中具有良好的综合性能。 展开更多
关键词 动态图 节点分类 图表示学习 分组查询注意力机制 图神经网络 GAM模块
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基于时序图神经网络的社会团体发现
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作者 李泽 赵伟超 徐慧雯 《计算机应用研究》 北大核心 2025年第9期2631-2636,共6页
在一些社会事件中,发现引起事件的社会团体对这些事件的治理具有重要的意义。针对现有社会团体发现任务中忽略团体对人物特征节点影响以及时间因素对团体发现影响的问题,提出了基于团体的节点表示模型G-GCN(group graph convolutional n... 在一些社会事件中,发现引起事件的社会团体对这些事件的治理具有重要的意义。针对现有社会团体发现任务中忽略团体对人物特征节点影响以及时间因素对团体发现影响的问题,提出了基于团体的节点表示模型G-GCN(group graph convolutional network),在对人物节点进行表示时融合团体的特征来增强节点表示。时间迁移对于团体发现有着重要意义,所以在G-GCN基础上提出了时序图神经网络TG-GCN(temporal-group graph convolutional network),引入了时间变化对节点表示变化的学习,实现了跨越时间的信息序列聚合表示,将相邻的事实转换为团体发现的演化表示。实验使用Yelp和Amazon数据集,团体划分的准确率提升了0.1,证明了TG-GCN对于团体发现任务的有效性。研究为事件治理提供了新视角,强调了节点表示与时间因素的重要性,对社会事件动态理解与预测具有价值。 展开更多
关键词 社会团体发现 图卷积神经网络 节点表示 时序图
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基于谱图理论的大规模复杂网络重要节点组挖掘算法
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作者 邢梓涵 刘丝语 +1 位作者 刘慧 陈凌霄 《物理学报》 北大核心 2025年第16期333-351,共19页
本文研究了无向复杂网络中基于谱图理论的节点组重要性挖掘问题.依据复杂网络牵制控制理论中节点重要性评价指标,删后Laplacian矩阵最小特征值较大者为重要受控节点.本文提出一种基于多重图特征线性融合与改进贪心搜索的重要节点组挖掘... 本文研究了无向复杂网络中基于谱图理论的节点组重要性挖掘问题.依据复杂网络牵制控制理论中节点重要性评价指标,删后Laplacian矩阵最小特征值较大者为重要受控节点.本文提出一种基于多重图特征线性融合与改进贪心搜索的重要节点组挖掘方法 (multi-metric fusion and enhanced greedy search algorithm,MFG算法).该方法首先通过融合度中心性、介数中心性、K-Shell值和电阻距离等多重指标,结合全局图特征(如图密度、平均路径长度等)构建线性加权融合模型,预筛选候选节点组以克服单一指标的局限性;其次,设计二阶邻域局部扰动与全局随机游走搜索策略,优化传统贪心算法的短视性,在预筛选节点组中迭代选择使得删后Laplacian矩阵最小特征值最大的节点,从而平衡局部最优与全局搜索能力;并利用改进的反幂法进行最小特征值的计算,降低了传统计算特征谱的复杂度,从而使得算法总体计算性能提升.最后,在经典网络模型和多个真实网络中进行仿真分析,利用不同算法挖掘重要节点组,计算删后拉普拉斯矩阵的最小特征值,利用SIR模型进行传播模拟,并从网络拓扑上分析不同算法筛选出的重要节点组特征.结果表明MFG算法相比其他几种算法挖掘重要节点组的效果更好,对于社交网络信息传播控制具有指导意义. 展开更多
关键词 复杂网络 节点组重要性 预筛选算法 删后拉普拉斯矩阵谱图理论
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