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一种基于面结构特征的病理切片图像拼接算法 被引量:3
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作者 王国钧 罗孝 +1 位作者 陈礼民 曹红萍 《中国生物医学工程学报》 EI CAS CSCD 北大核心 2004年第2期121-126,共6页
本研究是对“基于相关性的病理切片图像的配准算法”的一种改进算法 ,以面结构特征作为模板 ,采用求配准度的方法寻求图像匹配。算法的速度较快 ,稳定性更高 ,在实验中取得了更为满意的配准效果。
关键词 远程会诊 图像拼接 面结构特征 配准度
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X线头影测量在分析OSAS患者颅面结构特征中的应用进展 被引量:10
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作者 辛洪哲 贾培增 《北京口腔医学》 CAS 2005年第3期202-204,共3页
阻塞性睡眠呼吸暂停综合征(OSAS)是一种临床常见疾患,由多种因素引起,而且机制复杂。患者常常表现出一定的颅面及上气道形态结构特征。而X线头影测量作为一种常用的测量分析手段,已经被引入应用于OSAS临床治疗的多个方面:探讨疾病机理... 阻塞性睡眠呼吸暂停综合征(OSAS)是一种临床常见疾患,由多种因素引起,而且机制复杂。患者常常表现出一定的颅面及上气道形态结构特征。而X线头影测量作为一种常用的测量分析手段,已经被引入应用于OSAS临床治疗的多个方面:探讨疾病机理、辅助诊断、判断阻塞部位、协助选择治疗措施、分析治疗机理等。本文对OSAS患者的颅面及上气道形态特点以及X线头影测量分析在OSAS临床治疗中的应用做一综述。 展开更多
关键词 X线头影测量分析 OSAS患者 面结构特征 阻塞性睡眠呼吸暂停综合征 上气道形态 临床治疗 临床常见 疾病机理 辅助诊断
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安氏Ⅱ^1分类高角型错的颅面结构特征 被引量:1
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作者 孙伟 孙新华 《继续医学教育》 2010年第2期32-34,共3页
安氏Ⅱ1分类高角型错是临床上常见的错畸形,学者们对其形成机制曾作了大量研究,认为其形成机制错综复杂,表现形式多种多样。以往的临床诊断多以安氏分类为主,只注意到矢状向错,往往忽略了垂直向的不调。近年来人们逐渐认识到垂直面型... 安氏Ⅱ1分类高角型错是临床上常见的错畸形,学者们对其形成机制曾作了大量研究,认为其形成机制错综复杂,表现形式多种多样。以往的临床诊断多以安氏分类为主,只注意到矢状向错,往往忽略了垂直向的不调。近年来人们逐渐认识到垂直面型在错畸形诊断和治疗中的重要性,并且随着对安氏Ⅱ1分类错垂直骨面型形态学研究的深入,对其形态表现差异的认识也逐步加深。本文10个方面对安氏Ⅱ1分类高角型错的颅面部特征进行综述。 展开更多
关键词 安氏Ⅱ1分类 高角 面结构特征
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安氏Ⅱ类错的颅面结构特征研究进展 被引量:3
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作者 傅燕龙 陈永辉 《口腔医学研究》 CAS CSCD 北大核心 2009年第6期803-805,共3页
关键词 安氏Ⅱ类错[牙合] 面结构特征 矢状关系不调 下颌牙弓 正畸医师 上颌牙弓 矢状方向 垂直方向
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Crouzon综合征颅面结构特征2例报告 被引量:1
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作者 朱卫东 王林 《口腔医学》 CAS 2001年第3期133-133,共1页
关键词 CROUZON综合征 面结构特征 诊断 治疗 病例报告
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Research on time structure characteristic of gas concentration sequence in the working face 被引量:3
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作者 HE Li-wen SONG Yi +1 位作者 SHI Shi-liang LI Xi-bin 《Journal of Coal Science & Engineering(China)》 2011年第3期311-315,共5页
In the procedure of coal industry production, the losses of the persons and economy caused by the gas explosion accidents are most serious, therefore, prevention and control of the gas explosion accident of the coal m... In the procedure of coal industry production, the losses of the persons and economy caused by the gas explosion accidents are most serious, therefore, prevention and control of the gas explosion accident of the coal mines is an important issue needed to be solved urgently in the safety production work of our coal mines. The characteristic of time structure variation index characteristic was analyzed about gas concentration sequence of three measure points in the NO. 1I 1024 working face. It was found that the value of time variation about three measure points was mostly 1〈δ≤1.5, and gas emission presented consistently strong-clustering state twice, and the value of time variation presented continuous variation state in the active stage of gas concentration. Complex characteristics of the value indicated gas emission was continuously variable in time or space and presented the complex nonlinear characteristics. So the characteristic about gas emission system was correctly depicted and analyzed to gas emission system according to the relation of its state variation and essential of nonlinear system. The result also provided reliable warranty for its continued nonlinear research on gas emission. 展开更多
关键词 time structure gas concentration SEQUENCE working face NONLINEAR
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Eight-body central configuration for conjugate-nested regular tetrahedrons
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作者 刘学飞 《Journal of Chongqing University》 CAS 2007年第4期294-298,共5页
The sufficient and necessary conditions, the existence and uniqueness of a new class of central configuration in R^3, for the conjugate-nest consisting of two regular tetrahedrons, are proved. If the configuration is ... The sufficient and necessary conditions, the existence and uniqueness of a new class of central configuration in R^3, for the conjugate-nest consisting of two regular tetrahedrons, are proved. If the configuration is a central configuration, then all masses of outside layer are equivalent, and the masses of inside layer are also equivalent. At the same time p (the ratio of the sizes) and mass ratio τ=m^/m must be satisfied by some formulas. For any radius ratios ρ∈(0, 0.152996 918 2) or (0.715 223 148 7, 1.398 165 037), there is only one central configuration. Otherwise, for any given mass ratio τ, there may exist more than one central configuration. 展开更多
关键词 eight-body problem conjugate-nested tetrahedrons existence and uniqueness central configuration
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A Preliminary Analysis of Relations Between Tectonic Deformation of Sedimentary Cover and Basement in Kuqa Depression
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作者 LiuJie QuGuosheng +3 位作者 TongXiaoguang SongHuizhen ZhouQing ZhangNing 《Earthquake Research in China》 2004年第4期406-416,共11页
Study of seismic activity in the Kuqa area enables us to infer some possible active faults in basement from the epicentral distribution on different profiles. The relations between active faults in the basement and su... Study of seismic activity in the Kuqa area enables us to infer some possible active faults in basement from the epicentral distribution on different profiles. The relations between active faults in the basement and surface structures are analyzed and the difference between sedimentary cover and basement in their deformation characteristics and the genesis are discussed. The following conclusions have been drawn: (1) the epicentral distribution indicates that, the east Qiulitag and south and north Qiulitag deep faults in the basement correspond to the east and west Qiulitag anticlines, respectively. Moreover, deep faults also exist beneath the Yiqiklik and Yaken anticlines. It indicates that the formation of surface structures is controlled by deep structures; (2) A NE-trending strike-slip fault develops along the line from the western termination of Yiqiklik structure to Dongqiu Well 5 and a NW-trending active fault on the western side of Baicheng. The two active faults across the tectonic strike are the main causes for tectonic segmentation of the Kuqa depression and possibly the cause for the middle segment (Kuqa-Baicheng) of the depression to be more shortened than both its eastern and western terminations; (3) The difference between the sedimentary cover and basement in their deformation characteristics depends mainly on the different properties of media between them. The lithospheric strength of the basement in the basin is fairly high, which determines the basement deformation to be mainly of brittle fracture——seismic activity. While the strength of sedimentary cover is low, where there exist weak thin layers, such as coal and gyps. Under the effect of strong tectonic compression, the sedimentary rocks may undergo strong viscous or plastic flow deformation; meanwhile, an aseismic detachment may take place along the weak layers. 展开更多
关键词 SEISMICITY Surface structure Basement fault Deformation character Kuqa depression
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Engineering geological classification of the structural planes for hydroelectric projects in Emeishan Basalts 被引量:3
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作者 SUN Shu-qin HUANG Run-qiu +1 位作者 PEI Xiang-jun ZHAO Song-jiang 《Journal of Mountain Science》 SCIE CSCD 2016年第2期330-341,共12页
The scale and characteristics of rock mass are important indexes of the rock mass structural plane classification. This paper firstly analyzes the spatial distribution characteristics, the structural plane types (ori... The scale and characteristics of rock mass are important indexes of the rock mass structural plane classification. This paper firstly analyzes the spatial distribution characteristics, the structural plane types (original structural plane, tectonic structural plane and hypergenic structural plane) and the associated features of the Emeishan basalts and then studies the classification schemes of the built hydropower structure planes of different rock areas (the east district, the central district and the west district) in the Emeishan basalt distribution area, Southwest China. Based on the analysis and comparison of the scale and the engineering geological characteristics of the typical structure planes in the basalt hydroelectric Stations, the types of structural planes are used in the first order classification. The secondary order classification is made by considering the impact factors of rock mass quality, e.g., the state of the structural planes, infilling, joint opening, extending length, the grade of weathering and strength. The engineering geological classification for Emeishan basalt is proposed. Because there are no evidences of a large structure presenting in study area, the first-order (Ⅰ) controlling structural planes do not appear in the classification, there only appear Ⅱ, Ⅲ, Ⅳ and Ⅴ grade structural planes influencing the rock-mass quality. According to the different rock-block types in bedding fault zone, the second-grade (Ⅱ) structural planes consisted of bedding fault zone is further classified into Ⅱ1, Ⅱ2 and Ⅱ3. The third-grade (Ⅲ) structural planes constructed by intraformational faulted zones are not subdivided. According to the different characteristics of intrusion, alteration and weathering unloading structural planes, the Ⅳ grade structure plane is divided into Ⅳ1, Ⅳ2 and Ⅳ3. According to the development characteristics of joints and fractures, the V grade structure plane is divided into fracture Ⅴ1 and columnar joint Ⅴ2. In all, the structural planes are classified into four groups with nine subsets. The research proposes the engineering geological classification of the structural plane for the hydropower project in the Emishan basalts, and the result of the study has a potential application in similar regions. 展开更多
关键词 Emeishan basalt Hydroelectric project Structural plane Bedding fault zone Engineering geological classification
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浅析船舶进出淡水港的艏艉吃水变化规律 被引量:1
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作者 翁齐鸣 《天津航海》 2013年第3期1-2,6,共3页
船舶进出淡水港,舷外水密度发生改变,将使艏艉吃水也跟着改变,在航道水深较浅,船底富余水深不足的情况下,这种改变将对船舶操纵产生影响,甚至威胁到船舶的安全航行。因此,有必要对船舶进出淡水港的艏艉吃水变化情况进行研究,掌握其变化... 船舶进出淡水港,舷外水密度发生改变,将使艏艉吃水也跟着改变,在航道水深较浅,船底富余水深不足的情况下,这种改变将对船舶操纵产生影响,甚至威胁到船舶的安全航行。因此,有必要对船舶进出淡水港的艏艉吃水变化情况进行研究,掌握其变化规律,以便采取相应的措施抵消其影响,保证船舶的安全航行。文章对此进行初步的探讨,试图找出其中的变化规律。 展开更多
关键词 平行沉浮吃水差水线积中心排水体积中心艉部结构特征
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Velocity Structure Beneath Active Faults and Seismic Tectonic Characteristics in the Beijing Area
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作者 Gao Zhanwu Chen Qifu +2 位作者 Huang Jinli Qi Cheng Li Le 《Earthquake Research in China》 2011年第1期59-69,共11页
Velocity structure beneath active faults in the Beijing area has been discussed,based on the digital crustal model of velocity from deep seismic sounding profiles and tomography imaging of P waves. We found that there... Velocity structure beneath active faults in the Beijing area has been discussed,based on the digital crustal model of velocity from deep seismic sounding profiles and tomography imaging of P waves. We found that there exists nearly vertical deep faults beneath the Shunyi Depression and the Machiko Depression,which are very likely to be seismogenic faults in the future. In the superficial crust,the north segment of the Shunyi-QianmenLiangxiang fault,the north segment of the Huangzhuang-Gaoliying fault and the Qinghe fault show a trend to converge but without intersecting with vertical deep faults. This kind of seismo-tectonic state has great potential to generate large earthquakes. 展开更多
关键词 Active fault Velocity structure Beijing area
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Leaky modes and the first arrivals in cased boreholes with poorly bonded conditions 被引量:7
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作者 XiuMei Zhang XiuMing Wang HaiLan Zhang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第2期49-56,共8页
The generation mechanism of the first arrivals in the cased boreholes for the poorly bonded conditions is investigated. Based on the analyses of the Riemann surface structure of the characteristic function, the disper... The generation mechanism of the first arrivals in the cased boreholes for the poorly bonded conditions is investigated. Based on the analyses of the Riemann surface structure of the characteristic function, the dispersion features, excitation spectra and contributions of modes excited in the cased boreholes with different cementing types are studied. The phase velocity dispersion studies of leaky modes show that high-order modes form "plateau" regions with one approximate velocity denoted by v separated by their cutoff frequencies, in which the phase velocity changes little with a considerable frequency range, while the group velocity keeps a relatively constant high value. Usually, the operation frequency range of a specific cementing evaluation acoustic logging tool is covered by such a "plateau" region. Mode excitation and contribution analyses show that the first arrivals in the cased boreholes for the poorly bonded conditions are the contributions from leaky modes, where the traveling velocity of the first arrivals processed by slowness time coherence(STC) method is equal to the approximated velocity v. Analyses on generation of leaky modes in the cased boreholes supplement the understanding of the generation mechanism of the first arrivals. 展开更多
关键词 leaky modes cased borehole dispersion curves cement bonding conditions
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Nanomagnetic CoPt truncated octahedrons:facile synthesis,superior electrocatalytic activity and stability for methanol oxidation 被引量:5
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作者 Tianyu Xia Jialong Liu +3 位作者 Shouguo Wang Chao Wang Young Sun Rongming Wang 《Science China Materials》 SCIE EI CSCD 2017年第1期57-67,共11页
Nanomagnetic CoPt truncated octahedral nanoparticles (TONPs) were successfully synthesised through a facile one-pot strategy. These single crystal CoPt TONPs with an average size of about 8 nm exhibit excellent elec... Nanomagnetic CoPt truncated octahedral nanoparticles (TONPs) were successfully synthesised through a facile one-pot strategy. These single crystal CoPt TONPs with an average size of about 8 nm exhibit excellent electrocatalytic performance of both activity and stability for methanol oxidation reaction (MOR). The mass and specific activities of CoPt TONPs is 8 and 6 times higher than that of standard commercial Pt/C, respectively. After accelerated durability test (ADT), the loss of electrochemical surface area (ECSA) for CoPt TONPs is only 18.5%, which is significantly less than that of commercial Pt/C (68.2%), indicating that CoPt TONPs possess much better stability than commercial Pt/C in the prolonged operation. The Curie temperature of CoPt TONPs down to 8 nm is as high as 350 K with weak ferromagntism at room temperature (RT), which is greatly valuable for recycling in the eletrocatalytic applications. 展开更多
关键词 truncated octahedral nanoparticles methanol oxida-tion reaction (MOR) accelerated durability test (ADT) ferro-magntism
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