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Influences of local factors on permafrost occurrence and their implications for Qinghai-Xizang Railway design 被引量:27
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作者 CHENG Guodong 《Science China Earth Sciences》 SCIE EI CAS 2004年第8期704-709,共6页
The construction of the Qinghai-Xizang Railway is facing some challenges posed by the presence of warm and ice-rich permafrost and predicted climate warming. To resolve these issues and ensure the railway a success, a... The construction of the Qinghai-Xizang Railway is facing some challenges posed by the presence of warm and ice-rich permafrost and predicted climate warming. To resolve these issues and ensure the railway a success, adjustments will have to be made in design strategies and principles. This paper presents several examples of permafrost-distribution anomaly caused by site-specific conditions. It analyzes the mechanism through which these local factors influence the occurrence and preservation of permafrost by modifying the heat convection and conduction patterns, and the amount of solar radiation received by the ground surface. A good understanding of these anomalies in permafrost occurrence is significant as it may provide some hints on the techniques and measures we can use to artificially simulate similar effects. A number of measures can be taken to lower ground temperature and to counter the effect of cli-mate warming. These measures include use of proper roadbed material and configuration, in order to adjust solar radiation, heat convection and conduction patterns. It is recommended that a new proactive approach be adopted in the railway design. This approach emphasizes the use of all the above-mentioned measures to cool down the roadbed. This is different from previous methods of preventing permafrost from thawing by utilizing more thermal resistant materials. 展开更多
关键词 local factor anomaly in PERMAFROST occurrence cooled roadbed Qinghai-Xizang Railway climate warming.
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Three-dimensional stability of landslides based on local safety factor 被引量:4
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作者 YANG Tao Man-chu Ronald YEUNG +2 位作者 YANG Bing LIU Yong-jiang YANG Yan-xin 《Journal of Mountain Science》 SCIE CSCD 2016年第9期1515-1526,共12页
Unlike the limit equilibrium method(LEM), with which only the global safety factor of the landslide can be calculated, a local safety factor(LSF) method is proposed to evaluate the stability of different sections of a... Unlike the limit equilibrium method(LEM), with which only the global safety factor of the landslide can be calculated, a local safety factor(LSF) method is proposed to evaluate the stability of different sections of a landslide in this paper. Based on three-dimensional(3D) numerical simulation results, the local safety factor is defined as the ratio of the shear strength of the soil at an element on the slip zone to the shear stress parallel to the sliding direction at that element. The global safety factor of the landslide is defined as the weighted average of all local safety factors based on the area of the slip surface. Some example analyses show that the results computed by the LSF method agree well with those calculated by the General Limit Equilibrium(GLE) method in two-dimensional(2D) models and the distribution of the LSF in the 3D slip zone is consistent with that indicated by the observed deformation pattern of an actual landslide in China. 展开更多
关键词 Landslide stability local safety factor Stability analysis method Slip mechanism
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Obtaining Profiles Based on Localized Non-negative Matrix Factorization 被引量:2
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作者 JIANGJi-xiang XUBao-wen +1 位作者 LUJian-jiang ZhouXiao-yu 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期580-584,共5页
Nonnegative matrix factorization (NMF) is a method to get parts-based features of information and form the typical profiles. But the basis vectors NMF gets are not orthogonal so that parts-based features of informatio... Nonnegative matrix factorization (NMF) is a method to get parts-based features of information and form the typical profiles. But the basis vectors NMF gets are not orthogonal so that parts-based features of information are usually redundancy. In this paper, we propose two different approaches based on localized non-negative matrix factorization (LNMF) to obtain the typical user session profiles and typical semantic profiles of junk mails. The LNMF get basis vectors as orthogonal as possible so that it can get accurate profiles. The experiments show that the approach based on LNMF can obtain better profiles than the approach based on NMF. Key words localized non-negative matrix factorization - profile - log mining - mail filtering CLC number TP 391 Foundation item: Supported by the National Natural Science Foundation of China (60373066, 60303024), National Grand Fundamental Research 973 Program of China (2002CB312000), National Research Foundation for the Doctoral Program of Higher Education of China (20020286004).Biography: Jiang Ji-xiang (1980-), male, Master candidate, research direction: data mining, knowledge representation on the Web. 展开更多
关键词 localized non-negative matrix factorization PROFILE log mining mail filtering
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Anomaly IoT Node Detection Based on Local Outlier Factor and Time Series 被引量:2
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作者 Fang Wang Zhe Wei Xu Zuo 《Computers, Materials & Continua》 SCIE EI 2020年第8期1063-1073,共11页
The heterogeneous nodes in the Internet of Things(IoT)are relatively weak in the computing power and storage capacity.Therefore,traditional algorithms of network security are not suitable for the IoT.Once these nodes ... The heterogeneous nodes in the Internet of Things(IoT)are relatively weak in the computing power and storage capacity.Therefore,traditional algorithms of network security are not suitable for the IoT.Once these nodes alternate between normal behavior and anomaly behavior,it is difficult to identify and isolate them by the network system in a short time,thus the data transmission accuracy and the integrity of the network function will be affected negatively.Based on the characteristics of IoT,a lightweight local outlier factor detection method is used for node detection.In order to further determine whether the nodes are an anomaly or not,the varying behavior of those nodes in terms of time is considered in this research,and a time series method is used to make the system respond to the randomness and selectiveness of anomaly behavior nodes effectively in a short period of time.Simulation results show that the proposed method can improve the accuracy of the data transmitted by the network and achieve better performance. 展开更多
关键词 local outlier factor time series Internet of Things anomaly node detection
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Anomalous Cell Detection with Kernel Density-Based Local Outlier Factor 被引量:2
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作者 Miao Dandan Qin Xiaowei Wang Weidong 《China Communications》 SCIE CSCD 2015年第9期64-75,共12页
Since data services are penetrating into our daily life rapidly, the mobile network becomes more complicated, and the amount of data transmission is more and more increasing. In this case, the traditional statistical ... Since data services are penetrating into our daily life rapidly, the mobile network becomes more complicated, and the amount of data transmission is more and more increasing. In this case, the traditional statistical methods for anomalous cell detection cannot adapt to the evolution of networks, and data mining becomes the mainstream. In this paper, we propose a novel kernel density-based local outlier factor(KLOF) to assign a degree of being an outlier to each object. Firstly, the notion of KLOF is introduced, which captures exactly the relative degree of isolation. Then, by analyzing its properties, including the tightness of upper and lower bounds, sensitivity of density perturbation, we find that KLOF is much greater than 1 for outliers. Lastly, KLOFis applied on a real-world dataset to detect anomalous cells with abnormal key performance indicators(KPIs) to verify its reliability. The experiment shows that KLOF can find outliers efficiently. It can be a guideline for the operators to perform faster and more efficient trouble shooting. 展开更多
关键词 data mining key performance indicators kernel density-based local outlier factor density perturbation anomalous cell detection
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Evaluate the Role of Socio-cultural Factors in the Global Localization of TNC Activity
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作者 关静雯 《中山大学研究生学刊(自然科学与医学版)》 2010年第2期66-72,共7页
As an increasing number of firms are exercising transnational operations to occupy markets and exploit location-specific factors,some scholars claimed that 'the world is flat' and the local particularities no ... As an increasing number of firms are exercising transnational operations to occupy markets and exploit location-specific factors,some scholars claimed that 'the world is flat' and the local particularities no longer matter for the 'invincible' transnational corporations(TNC).But I argue that there exist some socio-cultural factors in the host countries influencing the actions of TNCs.I point out six local factors which include social norms,local attitudes,class formation,family structure, religion,and consumption pattern.Social norms are regulating TNCs' activities and local attitudes in varying contexts are encouraging or resisting against the transnational operators.Class formation generates new demands benefiting TNCs ' expansion. Religion structure and family value are reshaping TNCs' operational practices in production as well as distribution spheres.The location-specific consumption patterns are transforming TNCs' operations,deepening their territorial embeddedness,or even exposing them to the danger of overlocalization. 展开更多
关键词 摘要 编辑部 编辑工作 读者
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A comprehensive factor model of growth velocity of green algae and diatoms in local lake area
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作者 Zhihong WANG Fuyi CUI +1 位作者 Jie JIA Wenxuan CHEN 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期163-163,共1页
关键词 藻类 速度模型 生长速度 盐度
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THE FACTORS AND TREATMENT OF LOCAL RECURRENCE AFTER RADICAL RESECTION RESERVING THE ANUS IN THE PATIENTS WITH RECTAL CANCER
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作者 单吉贤 陈峻青 +1 位作者 张文范 齐春莲 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期73-76,共4页
Of seventy-one patients with rectal cancer after radical resection retaining the anus, 15 developed local recurrence with a recurrence rate of 21.1%. Local recurrence was correlated with improper safety margin from th... Of seventy-one patients with rectal cancer after radical resection retaining the anus, 15 developed local recurrence with a recurrence rate of 21.1%. Local recurrence was correlated with improper safety margin from the lower edge of cancer to the anal end. There was statistical significant difference between 3 cm or more and 2 cm or less. The local recurrence was also related to the pathologic stage, histologic differentiation and implant of free cancer cells. It is suggested that the surgical indication of saving the anus be strict and without stretching, the safety margin from the lower edge of cancer to the anal end should not be less than 2 cm in early rectal cancer and not less than 4 cm in advanced lesions. During the operation, no touching tumor technique, thorough rinsing of the peritoneal cavity and pre- or post-operative radiotherapy are important for prevention of local recurrence. Early local recurrent rectal cancer can be detected by periodic examinations. 展开更多
关键词 THE factorS AND TREATMENT OF local RECURRENCE AFTER RADICAL RESECTION RESERVING THE ANUS IN THE PATIENTS WITH RECTAL CANCER
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Risk factors for local recurrence and appropriate surveillance interval after endoscopic resection 被引量:4
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作者 Yoriaki Komeda Tomohiro Watanabe +10 位作者 Toshiharu Sakurai Masashi Kono Kazuki Okamoto Tomoyuki Nagai Mamoru Takenaka Satoru Hagiwara Shigenaga Matsui Naoshi Nishida Naoko Tsuji Hiroshi Kashida Masatoshi Kudo 《World Journal of Gastroenterology》 SCIE CAS 2019年第12期1502-1512,共11页
BACKGROUND Risk factors for local recurrence after polypectomy, endoscopic mucosal resection(EMR), and endoscopic submucosal dissection(ESD) have not been identified.Additionally, the appropriate interval for endoscop... BACKGROUND Risk factors for local recurrence after polypectomy, endoscopic mucosal resection(EMR), and endoscopic submucosal dissection(ESD) have not been identified.Additionally, the appropriate interval for endoscopic surveillance of colorectal tumors at high-risk of local recurrence has not been established.AIM To clarify the clinicopathological characteristics of recurrent lesions after endoscopic colorectal tumor resection and determine the appropriate interval.METHODS Three hundred and sixty patients(1412 colorectal tumors) who underwent polypectomy, EMR, or ESD and received endoscopic surveillance subsequently for more than one year to detect local recurrence were enrolled in this study. The clinicopathological factors associated with local recurrence were determined via univariate and multivariate analyses.RESULTS Local recurrence was observed in 31 of 360(8.6%) patients [31 of 1412(2.2%)lesions] after colorectal tumor resection. Piecemeal resection, tumor size of more than 2 cm, and the presence of villous components were associated with colorectal tumor recurrence after endoscopic resection. Of these three factors, the piecemeal resection procedure was identified as an independent risk factor for recurrence. Colorectal tumors resected into more than five pieces were associated with a high risk of recurrence since the average period from resection torecurrence in these cases was approximately 3 mo. The period to recurrence in cases resected into more than 5 pieces was much shorter than that in those resected into less than 4 pieces(3.8 ± 1.9 mo vs 7.9 ± 5.0 mo, P < 0.05).CONCLUSION Local recurrence of endoscopically treated colorectal tumors depends upon the outcome of first endoscopic procedure. Piecemeal resection was the only significant risk factor associated with local recurrence after endoscopic resection. 展开更多
关键词 local RECURRENCE COLORECTAL tumor ENDOSCOPIC SURVEILLANCE Piecemeal RESECTION Risk factors
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Fast parallel factor decomposition technique for coherently distributed source localization 被引量:2
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作者 CHENG Qianlin ZHANG Xiaofei CAO Renzheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期667-675,共9页
This paper links parallel factor(PARAFAC) analysis to the problem of nominal direction-of-arrival(DOA) estimation for coherently distributed(CD) sources and proposes a fast PARAFACbased algorithm by establishing... This paper links parallel factor(PARAFAC) analysis to the problem of nominal direction-of-arrival(DOA) estimation for coherently distributed(CD) sources and proposes a fast PARAFACbased algorithm by establishing the trilinear PARAFAC model.Relying on the uniqueness of the low-rank three-way array decomposition and the trilinear alternating least squares regression, the proposed algorithm achieves nominal DOA estimation and outperforms the conventional estimation of signal parameter via rotational technique CD(ESPRIT-CD) and propagator method CD(PM-CD)methods in terms of estimation accuracy. Furthermore, by means of the initialization via the propagator method, this paper accelerates the convergence procedure of the proposed algorithm with no estimation performance degradation. In addition, the proposed algorithm can be directly applied to the multiple-source scenario,where sources have different angular distribution shapes. Numerical simulation results corroborate the effectiveness and superiority of the proposed fast PARAFAC-based algorithm. 展开更多
关键词 source localization coherently distributed (CD)source parallel factor analysis propagator method (PM) trilin-ear decomposition
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Influencing factors on the accuracy of local geoid model
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作者 Shazad Jamal Jalal Tajul Ariffin Musa +3 位作者 Ami Hassan Md Din Wan Anom Wan Aris WenBin Shen Muhammad Faiz Pa’suya 《Geodesy and Geodynamics》 2019年第6期439-445,共7页
Different modification methods and software programs were developed to obtain accurate local geoid models in the past two decades.The quantitative effect of the main factors on the accuracy of local geoid modeling is ... Different modification methods and software programs were developed to obtain accurate local geoid models in the past two decades.The quantitative effect of the main factors on the accuracy of local geoid modeling is still ambiguous and has not been clearly diagnosed yet.This study presents efforts to find the most influential factors on the accuracy of the local geoid model,as well as the amount of each factor’s effect quantitatively.The methodology covers extracting the quantitative characteristics of 16 articles regarding local geoid models of different countries.The Statistical Package of Social Sciences(SPSS)software formulated a strong multiple regression model of correlation coefficient r = 0.999 with a high significance coefficient of determination R^2 = 0.997 and adjusted R^2 = 0,98 for the required effective factors.Then,factor analysis is utilized to extract the dominant factors which include:accuracy of gravity data(40%),the density of gravity data(25%)(total gravity factors is 65%),the Digital Elevation Model(DEM)resolution(16%),the accuracy of GPS/leveling points(10%)and the area of the terrain of the country/state under the study(9%).These results of this study will assist in developing more accurate local geoid models. 展开更多
关键词 ACCURACY of local GEOID MODEL MULTIPLE regression MODEL Influence factorS
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Local HIV/AIDS NGOs and Client Satisfaction: Dimensions and Explanatory Factors through a Multilevel Regression Analysis 被引量:1
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作者 Maurice T. Agonnoude François Champagne Nicole Leduc 《Open Journal of Epidemiology》 2020年第3期303-322,共20页
<strong>Background:</strong> HIV/AIDS Non-governmental organizations (NGOs) in Benin can use evaluations (including client satisfaction surveys) as tools to improve the effectiveness of their interventions... <strong>Background:</strong> HIV/AIDS Non-governmental organizations (NGOs) in Benin can use evaluations (including client satisfaction surveys) as tools to improve the effectiveness of their interventions. <strong>Objective:</strong> It is to identify the dimensions of NGO clients’ satisfaction and their associated factors. <strong>Methods:</strong> We conducted a cross-sectional survey of 2413 clients receiving both preventive and curative services from 31 NGOs working in HIV/AIDS prevention-screening and providing care to persons living with HIV. <strong>Results:</strong> We identified four dimensions of satisfaction relevant to our setting: reception and humane attitude, accessibility of care and resources, staff availability and competence and continuity of care. Individual factors [(age positively and gender (men negatively)] statistically significantly influenced global satisfaction and three of its four dimensions but the strength of these associations was too weak. Concerning organizational factors, involvement in evaluation had a negative effect on reception and humane attitude. A local source as principal source of funding was associated with greater satisfaction with accessibility of care and resources, while foreign partners as the principal source of funding were associated with greater satisfaction in terms of both global satisfaction and its dimensions, except for continuity of care. Organizational factors explain from 12.5% to 15.6% of the variance of global satisfaction and its dimensions (except for continuity of care). <strong>Conclusion:</strong> These information on the global satisfaction and its dimensions as well as the influencing factors are important for NGOs and their partners as these can help them to plan and implement actions to improve performance. 展开更多
关键词 local NGO HIV/AIDS Client Satisfaction Individual and Organizational factors BENIN
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基于局部离群因子与隔离森林的激光超声缺陷检测
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作者 李阳 朱文博 +4 位作者 静丰羽 叶中飞 马云瑞 周洋 邹云 《郑州大学学报(工学版)》 CAS 北大核心 2025年第1期105-112,共8页
针对激光超声(LU)缺陷检测中最大振幅图存在伪像的问题,结合主成分分析(PCA)和两种无监督的机器学习算法局部离群因子(LOF)与隔离森林(IF),以实现对LU数据的无监督异常检测。首先,利用PCA算法对LU数据进行降维处理,减轻了LU数据的复杂度... 针对激光超声(LU)缺陷检测中最大振幅图存在伪像的问题,结合主成分分析(PCA)和两种无监督的机器学习算法局部离群因子(LOF)与隔离森林(IF),以实现对LU数据的无监督异常检测。首先,利用PCA算法对LU数据进行降维处理,减轻了LU数据的复杂度;其次,利用LOF算法和IF算法进行了数据异常值的识别分析,并利用累积分布函数和核密度估计确定异常值的阈值大小;最后,对比了LOF算法、IF算法以及最大振幅图的检测结果。结果表明:LOF算法有更优的缺陷识别精度和更低的误判率。 展开更多
关键词 激光超声 缺陷检测 主成分分析 局部离群因子 隔离森林 铝合金
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Impact and Analysis of Prognostic Factors in Patients with Non-Metastatic Esophageal Squamous Cell Carcinoma: A Retrospective Single Institution Study 被引量:1
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作者 M. Keita M. Bah +6 位作者 A. M. Koundouno M. Diallo A. Camara I. K. Conde Wenbin Shen B. Traore S. C. Zhu 《Open Journal of Internal Medicine》 2021年第4期265-274,共10页
<strong>Objective:</strong> To investigate the impact of local tumor factors on the prognosis of non-metastatic esophageal squamous cell carcinoma patients. <strong>Methods:</strong> We perform... <strong>Objective:</strong> To investigate the impact of local tumor factors on the prognosis of non-metastatic esophageal squamous cell carcinoma patients. <strong>Methods:</strong> We performed a retrospective analysis of data from 278 consecutive esophageal squamous cell carcinoma patients between January 2009 and December 2016. The prognosis factors such as the GTV volume, GTV maximum diameter, and GTV length were analyzed. <strong>Results:</strong> The results of ROC curve analysis showed that prognosis critical values of the GTV volume, GTV maximum diameter, and GTV length were 27.98 cm<sup>3</sup>, 1.80 and 5.85 cm, respectively. The result of the univariate analysis showed that the GTV volume (P = 0.0184), GTV maximum diameter (P = 0.0246), and GTV length (P = 0.0035) were the prognostic factors for overall survival;the barium meal length (P = 0.0149) was the prognostic factor for local control. The multivariate analysis showed that the barium meal length (P = 0.0013), GTV maximum diameter (P = 0.0047), and GTV length (P = 0.0032) as the independent prognostic factors associated with overall survival;the barium meal length (P = 0.0037) was the only independent prognostic factors for local control. <strong>Conclusion: </strong>The esophageal lesion length was the main prognosis factor for patients with non-metastatic esophageal squamous cell carcinoma. Therefore, we suggest that the physician must give enough attention to these patients in clinical practice, and give active treatment. 展开更多
关键词 Esophageal Squamous Cell Carcinoma RADIOTHERAPY Non-Metastasis Tumor local factors Prognosis
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Wave localization in randomly disordered periodic layered piezoelectric structures 被引量:11
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作者 Fengming Li Yuesheng Wang +1 位作者 Chao Hu Wenhu Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第6期559-567,共9页
Considering the mechnoelectrical coupling, the localization of SH-waves in disordered periodic layered piezoelectric structures is studied. The waves propagating in directions normal and tangential to the layers are c... Considering the mechnoelectrical coupling, the localization of SH-waves in disordered periodic layered piezoelectric structures is studied. The waves propagating in directions normal and tangential to the layers are considered. The transfer matrices between two consecutive unit cells are obtained according to the continuity conditions. The expressions of localization factor and localization length in the disordered periodic structures are presented. For the disordered periodic piezoelectric structures, the numerical results of localization factor and localization length are presented and discussed. It can be seen from the results that the frequency passbands and stopbands appear for the ordered periodic structures and the wave localization phenomenon occurs in the disordered periodic ones, and the larger the coefficient of variation is, the greater the degree of wave localization is. The widths of stopbands in the ordered periodic structures are very narrow when the properties of the consecutive piezoelectric materials are similar and the intervals of stopbands become broader when a certain material parameter has large changes. For the wave propagating in the direction normal to the layers the localization length has less dependence on the frequency, but for the wave propagating in the direction tangential to the layers the localization length is strongly dependent on the frequency. 展开更多
关键词 Disordered periodic layered piezoelectric structures Transfer matrix Lyapunov exponent localization factor localization length
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ELASTIC WAVE LOCALIZATION IN TWO-DIMENSIONAL PHONONIC CRYSTALS WITH ONE-DIMENSIONAL QUASI-PERIODICITY AND RANDOM DISORDER 被引量:8
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作者 Ali Chen Yuesheng Wang +2 位作者 Guilan Yu Yafang Guo Zhengdao Wang 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第6期517-528,共12页
The band structures of both in-plane and anti-plane elastic waves propagating in two-dimensional ordered and disordered (in one direction) phononic crystals are studied in this paper. The localization of wave propag... The band structures of both in-plane and anti-plane elastic waves propagating in two-dimensional ordered and disordered (in one direction) phononic crystals are studied in this paper. The localization of wave propagation due to random disorder is discussed by introducing the concept of the localization factor that is calculated by the plane-wave-based transfer-matrix method. By treating the quasi-periodicity as the deviation from the periodicity in a special way, two kinds of quasi phononic crystal that has quasi-periodicity (Fibonacci sequence) in one direction and translational symmetry in the other direction are considered and the band structures are characterized by using localization factors. The results show that the localization factor is an effective parameter in characterizing the band gaps of two-dimensional perfect, randomly disordered and quasi-periodic phononic crystals. Band structures of the phononic crystals can be tuned by different random disorder or changing quasi-periodic parameters. The quasi phononic crystals exhibit more band gaps with narrower width than the ordered and randomly disordered systems. 展开更多
关键词 phononic crystal quasi phononic crystal DISORDER localization factors plane-wavebased transfer-matrix method periodic average structure
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WAVE LOCALIZATION IN RANDOMLY DISORDERED PERIODIC PIEZOELECTRIC RODS WITH INITIAL STRESS 被引量:5
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作者 Yize Wang Fengming Li +2 位作者 Kikuo Kishimoto Yuesheng Wang Wenhu Huang 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第6期529-535,共7页
The elastic wave localization in disordered periodic piezoelectric rods with initial stress is studied using the transfer matrix and Lyapunov exponent method. The electric field is approximated as quasi-static. The ef... The elastic wave localization in disordered periodic piezoelectric rods with initial stress is studied using the transfer matrix and Lyapunov exponent method. The electric field is approximated as quasi-static. The effects of the initial stress on the band gap characteristics are investigated. The numerical calculations of localization factors and localization lengths are performed. It can be observed from the results that the band structures can be tuned by exerting the suitable initial stress. For different values of the piezoelectric rod length and the elastic constant, the band structures and the localization phenomena are very different. Larger disorder degree can lead to more obvious localization phenomenon. 展开更多
关键词 piezoelectric phononic crystal initial stress random disorder localization factor localization length
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WAVE LOCALIZATION IN RANDOMLY DISORDERED PERIODIC PIEZOELECTRIC RODS 被引量:9
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作者 Li Fengming Wang Yuesheng Chen Ali 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第1期50-57,共8页
在周期、混乱的周期的压电的杆的波浪繁殖在这篇论文被学习。在二个连续单位房间之间的转移矩阵根据连续性条件被获得。压电的材料的机电的联合被考虑。根据矩阵特征值的理论,在周期的结构的频率乐队被学习。而且,由在两个介绍混乱尺... 在周期、混乱的周期的压电的杆的波浪繁殖在这篇论文被学习。在二个连续单位房间之间的转移矩阵根据连续性条件被获得。压电的材料的机电的联合被考虑。根据矩阵特征值的理论,在周期的结构的频率乐队被学习。而且,由在两个介绍混乱尺寸更少长度和压电的陶艺的有弹性的常数,在混乱周期的结构的波浪本地化被使用矩阵特征值方法和 Lyapunov 代表方法也学习。调节了周期的结构,这被发现让频率通带和站乐队和本地化现象能发生在错误调子周期的结构。由于压电的效果,而且,为不能通过结构宣传的波浪的频率区域稍微随压电的常数的增加被增加。 展开更多
关键词 周期压电杆 波局限化 转移矩阵 局限因子 无序状态
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One-Dimensional Localization of Elastic Waves in Rib-Stiffened Plates 被引量:1
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作者 李凤明 胡超 黄文虎 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2002年第4期208-212,共5页
The 1 dimensional localization of elastic waves in disordered periodic multi span rib stiffened plates is investigated. The transfer matrix method is employed to obtain the transfer matrix of the system, and the metho... The 1 dimensional localization of elastic waves in disordered periodic multi span rib stiffened plates is investigated. The transfer matrix method is employed to obtain the transfer matrix of the system, and the method for calculating the Lyapunov exponents in continuous dynamic systems presented by Wolf is used to determine the localization factor. As examples, the numerical results of the localization factors are given for a disordered rib stiffened plate. The effects of the degree of disorder of span... 展开更多
关键词 rib stiffened plate wave localization transfer matrix method Lyapunov exponent localization factor
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Adjuvant radiochemotherapy for gastric cancer:should weuse prognostic factors to select patients? 被引量:3
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作者 Linda Agolli Riccardo Maurizi Enrici Mattia Falchetto Osti 《World Journal of Gastroenterology》 SCIE CAS 2016年第3期1131-1138,共8页
Radiotherapy has a not well-established role in the pre-operative and in the post-operative setting in gastric cancer(GC) patients. Randomized trials report controversial outcomes and impact on survival. In the D2 loc... Radiotherapy has a not well-established role in the pre-operative and in the post-operative setting in gastric cancer(GC) patients. Randomized trials report controversial outcomes and impact on survival. In the D2 loco-regional node resection era, after a wellperformed radical surgery, local treatment using radiotherapy combined to chemotherapy should be considered for locally advanced GC. Prognostic factors could help the better selection of subgroups that present high risk of loco-regional recurrence. Then, the addition of radiotherapy could improve the diseasefree survival and also quality of life. There are no large prospective studies that have assessed specific factors predicting for recurrence or survival, but only retrospective series, some of them including high number of patients with homogeneous characteristics. In locally advanced GC adding radiotherapy to the postoperative chemotherapy seems to improve outcomes and quality of life. Prognostic factors such as T-stage, N-status, nodal ratio, and other histological factors should be considered to submit patients to postoperative combined treatment. Larger prospective series are necessary to investigate the role of combined chemoradiation after radical D2-resection, especially in locally advanced GC. Further prospective investigations are needed to suggest prognostic factors that have significant impact on survival and recurrence, improving the management and outcomes, particularly in locally advanced GC patients. 展开更多
关键词 Gastric cancer ADJUVANT RADIOTHERAPY PROGNOSTIC factors localLY advanced disease Selectedpatients
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