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The role of multimodality imaging in calcified valves with infective endocarditis
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作者 Aker Amir Alexander Fuks +4 位作者 Salim Adawi Yuval Avidan Vsevolod Tabachnikov Amnon Eitan Avinoam Shiran 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第9期927-930,共4页
A 68-years old woman presented with ahistory of recurrent fever of 38-39°ac-companied by chills and weakness over the past month.Her physical examination was unremarkable except for an audible 3/6 ejection murmur... A 68-years old woman presented with ahistory of recurrent fever of 38-39°ac-companied by chills and weakness over the past month.Her physical examination was unremarkable except for an audible 3/6 ejection murmur at the 2nd right intercostal space.Her vital signs were normal with no fever at presentation.Laboratory tests showed elevated white blood count of 11,800cells/mm3 with a remarkable neutrophilia and elevated C-reactive protein of 14 mg/dL.Blood glucose,renal and liver function tests were all normal. 展开更多
关键词 ELEVATED modality FEVER
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 Structural health monitoring data information modal parameters damage identification AI method
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Interannual variability of boreal summer intraseasonal oscillation over the northwestern Pacific influenced by the Pacific Meridional Mode
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作者 Haoyu Zhou Pang-Chi Hsu +1 位作者 Lin Chen Yitian Qian 《Atmospheric and Oceanic Science Letters》 2025年第1期6-11,共6页
During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the s... During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns. 展开更多
关键词 Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional mode Moisture budget analysis
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Modeling Rules Fission and Modality Selection Using Ontology
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作者 Atef Zaguia Ahmad Wahbi +2 位作者 Moeiz Miraoui Chakib Tadj Amar Ramdane-Cherif 《Journal of Software Engineering and Applications》 2013年第7期354-371,共18页
Researchers in computer science and computer engineering devote a significant part of their efforts on communication and interaction between man and machine. Indeed, with the advent of multimedia and multimodal proces... Researchers in computer science and computer engineering devote a significant part of their efforts on communication and interaction between man and machine. Indeed, with the advent of multimedia and multimodal processing in real time, the computer is no longer considered only as a computational tool, but as a machine for processing, communication, collection and control. Many machines assist and support many activities in daily life. The main objective of this paper is to propose a new methodological solution by modeling an architecture that facilitates the work of multimodal system especially for a fission module. To realize such systems, we rely on ontology to integrate data semantically. Ontologies provide a structured vocabulary usedas support for data representation. This paper provides a better understanding of the fission system and multimodal interaction. We present our architecture and the description of the detection of optimal modalities. This is done by using an ontological model that contains different applicable scenarios and describes the environment where a multimodal system exists. 展开更多
关键词 MULTImodal System MULTImodal FISSION modality ONTOLOGY Interaction CONTEXT Pattern
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Models for amplitude fluctuation of underwater acoustic narrow band signal based on modified modal scintillation index 被引量:2
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作者 安良 方世良 陈励军 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期235-241,共7页
A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation i... A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation intervals.It is proved in an analytical form that the MMSI is a depth dependent signature and independent of the source level and the source range under the condition of the ideal waveguide while the classical modal scintillation index MSI depends on both the source level and the source range.The MSI and the MMSI in the Pekeris waveguide at 70 Hz are simulated with different source levels and source ranges by the Kraken normal mode model.The simulation results are consistent with the theoretical deduction.The MMSI probability density functions PDFs of different normal modes for surface and submerged sources are calculated using the mode filtering methods with the same variations of vertical motions.It is indicated that the PDFs can be used to separate the submerged and the surface sources except for the fourth mode. 展开更多
关键词 modified modal scintillation index amplitudefluctuation mode filtering Pekeris waveguide
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On Inspiration from Modality Value to the Teaching of College English
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作者 戈秀兰 《黑龙江生态工程职业学院学报》 2008年第6期117-118,共2页
This paper aims at examing how modality values are realized in native and non-native English news reporting and comparing the values they each take.By analyzing,the writer hopes to contribute to the awareness of forei... This paper aims at examing how modality values are realized in native and non-native English news reporting and comparing the values they each take.By analyzing,the writer hopes to contribute to the awareness of foreign language learners in terms of the importance of modality values in news analysis and make readers benefit from their reading,writing. 展开更多
关键词 modality modality VALUE news REPORTS functional GRAMMAR
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Analysis on the Modality of English News Report
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作者 肖蓉 《科技信息》 2011年第11期I0265-I0265,I0283,共2页
Modality is used to express subjective judgment as well as the speaker’s opinions and attitudes.This paper aims to analyze the reporters’orientation reflected by linguistic modal expressions in English news reports ... Modality is used to express subjective judgment as well as the speaker’s opinions and attitudes.This paper aims to analyze the reporters’orientation reflected by linguistic modal expressions in English news reports from the perspective of Systemic-Functional Grammar,especially from the perspective of type,value,orientation and polarity. 展开更多
关键词 modality NEWS REPORTS SYSTEMIC FUNCTIONAL GRAMMAR
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Radiotherapy as valid modality for hepatocellular carcinoma with portal vein tumor thrombosis 被引量:23
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作者 Jeong Il Yu Hee Chul Park 《World Journal of Gastroenterology》 SCIE CAS 2016年第30期6851-6863,共13页
Although the current standard treatment for hepatocellular carcinoma(HCC) with portal vein tumor thrombosis(PVTT) is sorafenib, many previous studies have established the need for a reliable local modality for PVTT co... Although the current standard treatment for hepatocellular carcinoma(HCC) with portal vein tumor thrombosis(PVTT) is sorafenib, many previous studies have established the need for a reliable local modality for PVTT control, which is a major cause of liver function deterioration and metastasis. Additionally, there is growing evidence for the prognostic significance of PVTT classification according to the location of tumor thrombosis. Favorable outcomes can be obtained by applying local modalities, including surgery or transarterial chemoembolization, especially in second-order or distal branch PVTT. Rapid control of PVTT could maintain or improve liver function and reduce intrahepatic as well as distant metastasis. Radiotherapy(RT) is one of the main locoregional treatment modalities in oncologic fields, but has rarely been used in HCC because of concerns regarding hepatic toxicity. However, with the development of advanced techniques, RT has been increasingly applied in HCC management. Randomized studies have yet to definitively prove the benefit of RT, but several comparative studies have justified the application of RT in HCC. The value of RT is especially noticeable in HCC with PVTT; several prospective and retrospective studies have reported favorable outcomes, including a 40% to 60% objective response rate and median overall survival of 15 mo to 20 mo in responders. In this review, we evaluate the role of RT as an alternative local modality in HCC with PVTT. 展开更多
关键词 HEPATOCELLULAR carcinoma Portal VEIN tumor THROMBOSIS RADIOTHERAPY Local modality Alternative
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Multimodality treatment in hepatocellular carcinoma patients with tumor thrombi in portal vein 被引量:80
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作者 Jia Fan Zhi Quan Wu +5 位作者 Zhao You Tang Jian Zhou Shuang Jian Qiu Zeng Chen Ma Xin Da Zhou Sheng Long Ye Liver Cancer Institute, Zhongshan Hospital, Fudan University Medical Center (Former Shanghai University), 136 Yixueyuan Road, Shanghai 200032, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第1期28-32,共5页
AIM: To compare the therapeutic effect and significances of multimodality treatment for hepatocellular carcinoma (HCC) with tumor thrombi in portal vein (PVTT). METHODS: HCC patients (n=147) with tumor thrombi in the ... AIM: To compare the therapeutic effect and significances of multimodality treatment for hepatocellular carcinoma (HCC) with tumor thrombi in portal vein (PVTT). METHODS: HCC patients (n=147) with tumor thrombi in the main portal vein or the first branch of portal vein were divided into four groups by the several therapeutic methods. There were conservative treatment group in 18 out of patients (group A); and hepatic artery ligation(HAL) and/or hepatic artery infusion (HAI) group in 18 patients (group B), in whom postoperative chemoembolization was done periodically; group of removal of HCC with PVTT in 79 (group C) and group of transcatheter hepatic arterial chemoembolization (TACE) or HAI and/or portal vein infusion (PVI) after operation in 32 (group D). RESULTS: The median survival period was 12 months in our series and the 1-,3-, and 5-year survival rates were 44.3%, 24.5% and 15.2%, respectively. The median survival times were 2, 5, 12 and 16 months in group A, B, C and D, respectively. The 1-, 3- and 5-year survival rates were 5.6%, 0% and 0% in group A; 22.2%, 5.6% and 0% in group B; 53.9%, 26.9% and 16.6% in group C; 79.3%, 38.9% and 26.8% in group D, respectively. Significant difference appeared in the survival rates among the groups (P 【 0.05). CONCLUSION: Hepatic resection with removal of tumor thrombi and HCC should increase the curative effects and be encouraged for the prolongation of life span and quality of life for HCC patients with PVTT, whereas the best therapeutic method for HCC with PVTT is with regional hepatic chemotherapy or chemoembolization after hepatic resection with removal of tumor thrombi. 展开更多
关键词 Chemoembolization Therapeutic Neoplasm Circulating Cells Adult Aged Antineoplastic Agents Carcinoma Hepatocellular Combined modality Therapy Comparative Study Female Hepatic Artery Humans LIGATION Liver Neoplasms Male Middle Aged Portal Vein Prognosis Research Support Non-U.S. Gov't Survival Rate
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ChatGPT for shaping the future of dentistry: the potential of multi-modal large language model 被引量:10
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作者 Hanyao Huang Ou Zheng +8 位作者 Dongdong Wang Jiayi Yin Zijin Wang Shengxuan Ding Heng Yin Chuan Xu Renjie Yang Qian Zheng Bing Shi 《International Journal of Oral Science》 SCIE CAS CSCD 2023年第3期377-389,共13页
The ChatGPT,a lite and conversational variant of Generative Pretrained Transformer 4(GPT-4)developed by OpenAI,is one of the milestone Large Language Models(LLMs)with billions of parameters.LLMs have stirred up much i... The ChatGPT,a lite and conversational variant of Generative Pretrained Transformer 4(GPT-4)developed by OpenAI,is one of the milestone Large Language Models(LLMs)with billions of parameters.LLMs have stirred up much interest among researchers and practitioners in their impressive skills in natural language processing tasks,which profoundly impact various fields.This paper mainly discusses the future applications of LLMs in dentistry.We introduce two primary LLM deployment methods in dentistry,including automated dental diagnosis and cross-modal dental diagnosis,and examine their potential applications.Especially,equipped with a cross-modal encoder,a single LLM can manage multi-source data and conduct advanced natural language reasoning to perform complex clinical operations.We also present cases to demonstrate the potential of a fully automatic Multi-Modal LLM AI system for dentistry clinical application.While LLMs offer significant potential benefits,the challenges,such as data privacy,data quality,and model bias,need further study.Overall,LLMs have the potential to revolutionize dental diagnosis and treatment,which indicates a promising avenue for clinical application and research in dentistry. 展开更多
关键词 modal equipped operations
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Single fundamental mode photonic crystal VCSEL with high power and low threshold current optimized by modal loss analysis 被引量:4
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作者 Yi-Yang Xie Qiang Kan +2 位作者 Chen Xu Kun Xu Hong-Da Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期200-207,共8页
The characteristics of the photonic crystal vertical cavity surface emitting lasers(PhC-VCSELs) were investigated by using the full vector finite-difference time-domain(FDTD) method through the transverse mode los... The characteristics of the photonic crystal vertical cavity surface emitting lasers(PhC-VCSELs) were investigated by using the full vector finite-difference time-domain(FDTD) method through the transverse mode loss analysis. PhC-VCSELs with different photonic crystal structures were analyzed theoretically and experimentally. Through combining the dual mode confinement of oxide aperture and seven-point-defect photonic crystal structure, the PhC-VCSELs with low threshold current of 0.9 mA and maximum output power of 3.1 mW operating in single fundamental mode were demonstrated. Mode loss analysis method was proven as a reliable and useful way to analyze and optimize the PhC-VCSELs. 展开更多
关键词 vertical cavity surface emitting lasers single fundamental mode mode loss
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Finite Element Modeling and Modal Analysis of Complicated Structure with Bolted Joints 被引量:3
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作者 蒲大宇 廖日东 +1 位作者 左正兴 冯慧华 《Journal of Beijing Institute of Technology》 EI CAS 2009年第3期273-277,共5页
A contact bolt model is proposed as a new modeling technique to investigate the complex structure with bolted joints for modal analysis and compared with the coupled bolt model, and the test results are given. Among t... A contact bolt model is proposed as a new modeling technique to investigate the complex structure with bolted joints for modal analysis and compared with the coupled bolt model, and the test results are given. Among these models, the coupled bolt model provides the best accurate responses compared with the experimental results. The contact bolt model shows the best effectiveness and usefulness in view of operational time. The bolt models proposed in this study are adopted for a dynamic characteristic analysis of a large diesel engine consisting of several parts which are connected by many bolts. The dynamic behavior of the entire engine structure was investigated by experiment. The coupled bolt model and the contact bolt model were applied to model the assembly of engine with high preload. The experimental results are in good agreement with the finite element method (FEM) results. Compared with the other models, the contact bolt model presented in this paper is more effective and useful in view of operational time and experience of analysts. 展开更多
关键词 finite element method(FEM) bolted joints modal analysis internal combustion engine
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Stress and modal birefringence of single-mode specialty optical fibers with three-stress regions 被引量:2
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作者 孟义朝 吴明华 《Journal of Shanghai University(English Edition)》 CAS 2011年第2期137-142,共6页
Stress-induced birefringence and modal birefringence of single-mode specialty optical fibers with three stress regions are numerically analyzed by the vector finite element method. Stress distribution and stress-induc... Stress-induced birefringence and modal birefringence of single-mode specialty optical fibers with three stress regions are numerically analyzed by the vector finite element method. Stress distribution and stress-induced birefringence distribution of three kinds of optical fibers with different cross structures are presented and compared, and the influence on the stress- induced birefringence by temperature change are analyzed as well. The results show that the fibers with three-stress regions have a lower linear birefringence, which is very important for the fabrication of the circular polaxization-maintalning fiber with high performance drawn from the same fiber preform by using the spinning method. 展开更多
关键词 specialty optical fiber stress-induced birefringence modal birefringence vector finite element method
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Numerical modeling on the interaction of internal solitary wave with slope-shelf and modal analysis 被引量:1
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作者 LI Qun XU Zhaoting CHEN Xu YU Jia 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第6期139-149,共11页
On the basis of a nonhydrostatic numerical model, the interaction of internal solitary wave with slope - shelf was studied. The breaking and polarity transformation were analyzed. A "kink" structure, due to shoaling... On the basis of a nonhydrostatic numerical model, the interaction of internal solitary wave with slope - shelf was studied. The breaking and polarity transformation were analyzed. A "kink" structure, due to shoaling topography and higher nonlinear effect, was found to be generated by the leading wave before breaking. Coherent vortex shedding behind the leading wave was presented. The evolution characteristics of the modal structure were analyzed based on the empirical orthogonal function method. The modal structure was complicated due to the effect of the variable topography, especially when breaking occurred. In the performed experiments, the contributions to the total variance from higher mode jumped from no more than 20% to over 40%. 展开更多
关键词 internal solitary wave modal structure empirical orthogonal function
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Terminal-Modality-Based Joint Call Admission Control Algorithm for Fair Radio Resource Allocation in Heterogeneous Cellular Networks 被引量:1
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作者 Olabisi E. Falowo 《International Journal of Communications, Network and System Sciences》 2012年第7期392-404,共13页
There is a problem of unfairness in allocation of radio resources among heterogeneous mobile terminals in heterogeneous wireless networks. Low-capability mobile terminals (such as single-mode terminals) suffer high ca... There is a problem of unfairness in allocation of radio resources among heterogeneous mobile terminals in heterogeneous wireless networks. Low-capability mobile terminals (such as single-mode terminals) suffer high call blocking probability whereas high-capability mobile terminals (such as quad-mode terminals) experience very low call blocking probability, in the same heterogeneous wireless network. This paper proposes a Terminal-Modality-Based Joint Call Admission Control (TJCAC) algorithm to reduce this problem of unfairness. The proposed TJCAC algorithm makes call admission decisions based on mobile terminal modality (capability), network load, and radio access technology (RAT) terminal support index. The objectives of the proposed TJCAC algorithm are to reduce call blocking/dropping probability, and ensure fairness in allocation of radio resources among heterogeneous mobile terminals in heterogeneous networks. An analytical model is developed to evaluate the performance of the proposed TJCAC scheme in terms of call blocking/dropping probability in a heterogeneous wireless network. The performance of the proposed TJCAC algorithm is compared with that of other JCAC algorithms. Results show that the proposed algorithm reduces call blocking/dropping probability in the networks, and ensure fairness in allocation of radio resources among heterogeneous terminals. 展开更多
关键词 CALL ADMISSION Control TERMINAL modality HETEROGENEOUS Terminals Radio Access Technology CALL DROPPING CALL Blocking Markov Chain Mobile Users
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Quest for the best endoscopic imaging modality for computer-assisted colonic polyp staging 被引量:2
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作者 Georg Wimmer Michael Gadermayr +8 位作者 Gernot Wolkersdorfer Roland Kwitt Toru Tamaki Jens Tischendorf Michael Hafner Shigeto Yoshida Shinji Tanaka Dorit Merhof Andreas Uhl 《World Journal of Gastroenterology》 SCIE CAS 2019年第10期1197-1209,共13页
BACKGROUND It was shown in previous studies that high definition endoscopy, high magnification endoscopy and image enhancement technologies, such as chromoendoscopy and digital chromoendoscopy [narrow-band imaging(NBI... BACKGROUND It was shown in previous studies that high definition endoscopy, high magnification endoscopy and image enhancement technologies, such as chromoendoscopy and digital chromoendoscopy [narrow-band imaging(NBI), iScan] facilitate the detection and classification of colonic polyps during endoscopic sessions. However, there are no comprehensive studies so far that analyze which endoscopic imaging modalities facilitate the automated classification of colonic polyps. In this work, we investigate the impact of endoscopic imaging modalities on the results of computer-assisted diagnosis systems for colonic polyp staging.AIM To assess which endoscopic imaging modalities are best suited for the computerassisted staging of colonic polyps.METHODS In our experiments, we apply twelve state-of-the-art feature extraction methods for the classification of colonic polyps to five endoscopic image databases of colonic lesions. For this purpose, we employ a specifically designed experimental setup to avoid biases in the outcomes caused by differing numbers of images per image database. The image databases were obtained using different imaging modalities. Two databases were obtained by high-definition endoscopy in combination with i-Scan technology(one with chromoendoscopy and one without chromoendoscopy). Three databases were obtained by highmagnification endoscopy(two databases using narrow band imaging and one using chromoendoscopy). The lesions are categorized into non-neoplastic and neoplastic according to the histological diagnosis.RESULTS Generally, it is feature-dependent which imaging modalities achieve high results and which do not. For the high-definition image databases, we achieved overall classification rates of up to 79.2% with chromoendoscopy and 88.9% without chromoendoscopy. In the case of the database obtained by high-magnification chromoendoscopy, the classification rates were up to 81.4%. For the combination of high-magnification endoscopy with NBI, results of up to 97.4% for one database and up to 84% for the other were achieved. Non-neoplastic lesions were classified more accurately in general than non-neoplastic lesions. It was shown that the image recording conditions highly affect the performance of automated diagnosis systems and partly contribute to a stronger effect on the staging results than the used imaging modality.CONCLUSION Chromoendoscopy has a negative impact on the results of the methods. NBI is better suited than chromoendoscopy. High-definition and high-magnification endoscopy are equally suited. 展开更多
关键词 ENDOSCOPY Colonic polyps Automated diagnosis system Narrow-band imaging CHROMOENDOSCOPY Imaging modalities Image enhancement technologies
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Extraction of real modes and physical matrices from modal testing
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作者 Wang Tong Zhang Lingmi Tee Kong Fah 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第2期219-227,共9页
A technique to extract real modes from the identified complex modes is presented in this paper, which enables the normalized real mode shapes, modal masses, and full or reduced mass and stiffness matrices to be obtain... A technique to extract real modes from the identified complex modes is presented in this paper, which enables the normalized real mode shapes, modal masses, and full or reduced mass and stiffness matrices to be obtained. The theoretical derivation of the method is provided in detail. An 11-DOF vibration system is used to validate the algorithm, and to analyze the effects of the number of modes utilized and measurement DOFs on the extraction results. Finally, the method is used to extract real modes from both experimental modal analysis and operational modal analysis. 展开更多
关键词 modal analysis complex mode real mode normalized mode shape modal mass
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基于主客观环流分型的强降水数值预报MODE检验方法及其在2019年暖季东北地区的应用
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作者 齐铎 崔晓鹏 +4 位作者 陈力强 黄丽君 刘松涛 卜文惠 王承伟 《大气科学》 CSCD 北大核心 2024年第3期1113-1130,共18页
本文构建了基于主客观环流分型的强降水数值预报空间检验(MODE)方法框架,并利用该框架对欧洲中期天气预报中心全球模式(ECMWF)和中国气象局区域中尺度数值天气预报模式(CMA_MESO)的2019年暖季东北地区强降水预报进行检验。结果表明,201... 本文构建了基于主客观环流分型的强降水数值预报空间检验(MODE)方法框架,并利用该框架对欧洲中期天气预报中心全球模式(ECMWF)和中国气象局区域中尺度数值天气预报模式(CMA_MESO)的2019年暖季东北地区强降水预报进行检验。结果表明,2019年暖季东北地区54个强降水日的环流型可分为:西风槽型(15个)、副热带高压影响型(13个)、急流型(5个)、西部(12个)和东部冷涡型(9个)。其中,西风槽型和急流型以区域性强降水为主,模式对其强降水发生与否的预报能力强,TS评分较高;西部、东部冷涡型强降水的局地性强,模式对其强降水发生与否的预报能力差,TS评分低;副热带高压影响型也以区域性强降水为主,模式对其强降水发生与否的预报能力也比较强,但是对其强降水质心位置、强度、面积等属性预报偏差较大,TS评分也相对较低。另外,从两种模式预报性能对比看,CMA_MESO强降水强度和面积预报较实况普遍偏强,虽然其预报的TS评分一般高于ECMWF,但其对强降水预报的空报率也都比ECMWF大,对强降水的属性预报偏差一致性一般也低于ECMWF,其预报的可订正性整体上不及ECMWF。 展开更多
关键词 主客观融合环流分型 东北冷涡客观识别 强降水 数值预报 mode检验
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Effect of Tire Repeated Root Modal on Tire Modelling with Experimental Modal
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作者 Zhenfeng Wang Yongchang Du +1 位作者 Mingming Dong Liang Gu 《Journal of Beijing Institute of Technology》 EI CAS 2017年第1期67-74,共8页
The effect of tire repeated root modal(RRM)on tire modeling with an experimental modal is studied.Firstly,a radial tire with radial and tangential RRMs is tested and analyzed.By multi-point exciting of the radial ti... The effect of tire repeated root modal(RRM)on tire modeling with an experimental modal is studied.Firstly,a radial tire with radial and tangential RRMs is tested and analyzed.By multi-point exciting of the radial tire,a multiple reference frequency domain method based on a least squares(LMS PolyMAX)algorithm is used to identify modal parameters.Then,modal stability diagram(MSD),modal indication function(MIF)and modal assurance criteria(Auto-MAC)matrix are utilized to induce multiple inputs multiple outputs(MIMO)frequency response function(FRF)matrixes.The tests reveal that notable repeated roots exist in both radial and tangential response modes.Their modal frequencies and damping factors are approximately the same,the amplitudes of modal vectors are in the same order of magnitude,and the mode shapes are orthogonal.Based on the works mentioned,the method of trigonometric series modal shapes fitting is adopted,the effects of RRM model on tire modeling with a vertical experimental modal are discussed.The final results show that the effects of considering the RRM shapes are equivalent to the tire mode shapes depended on rotating the tire’s different exciting points during tire modeling,and since considering the RRM,the tire mode shapes can be unified and fixed during tire modeling. 展开更多
关键词 modal test repeated root modal ploy MAX method tire model
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Parallel and Hierarchical Mode Association Clustering with an R Package <i>Modalclust</i>
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作者 Yansong Cheng Surajit Ray 《Open Journal of Statistics》 2014年第10期826-836,共11页
Modalclust is an R package which performs Hierarchical Mode Association Clustering (HMAC) along with its parallel implementation over several processors. Modal clustering techniques are especially designed to efficien... Modalclust is an R package which performs Hierarchical Mode Association Clustering (HMAC) along with its parallel implementation over several processors. Modal clustering techniques are especially designed to efficiently extract clusters in high dimensions with arbitrary density shapes. Further, clustering is performed over several resolutions and the results are summarized as a hierarchical tree, thus providing a model based multi resolution cluster analysis. Finally we implement a novel parallel implementation of HMAC which performs the clustering job over several processors thereby dramatically increasing the speed of clustering procedure especially for large data sets. This package also provides a number of functions for visualizing clusters in high dimensions, which can also be used with other clustering softwares. 展开更多
关键词 modality KERNEL Density Estimate mode CLUSTERING
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