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光纤形态传感器研究进展 被引量:2
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作者 杨洋 孔令宇 +3 位作者 蔡伟康 赵德龙 陈宇涛 宋章启 《半导体光电》 CAS 北大核心 2022年第4期642-654,共13页
光纤形态传感技术是解决柔性体形态测量、光电缆实时形态跟踪、医疗介入针轨迹实时跟踪等3D形态恢复问题的创新型技术方案。光纤形态传感技术以光纤作为敏感元件,传感器具有结构简单、易于嵌入安装、测量不需要视觉接触、耐腐蚀,以及抗... 光纤形态传感技术是解决柔性体形态测量、光电缆实时形态跟踪、医疗介入针轨迹实时跟踪等3D形态恢复问题的创新型技术方案。光纤形态传感技术以光纤作为敏感元件,传感器具有结构简单、易于嵌入安装、测量不需要视觉接触、耐腐蚀,以及抗电磁干扰等优点,适用于水下、地下等复杂环境中的大尺度结构形态测量。近年来,光纤形态传感器受到了越来越多的关注,文章综述了光纤形态传感技术的最新研究进展,以一维曲率传感器、全向型曲率传感器和空间形态传感器为线索,介绍了各阶段传感器的研究现状以及面临的挑战。 展开更多
关键词 光纤 形态 曲率 光栅 多芯光纤
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浅析立体构成设计学习要素 被引量:4
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作者 田景竹 《贵州大学学报(艺术版)》 2008年第1期71-73,共3页
立体构成是学习形态创造规律的方法之一,是多向度的艺术,是利用各种材料按照美的原则创造出具生命力感的新形态的过程。在立体构成设计时需构架好空间构想力、立体感的创造及空间形态创造。
关键词 立体构成 空间形态 立体 空间空间形态
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谈词的形象色彩的两个问题
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作者 马春玲 《萍乡高等专科学校学报》 1997年第2期29-30,共2页
许多词,除了具有概念性的抽象意义之外,还同时具有形象感,以生动、具体的形象诉诸人们的视觉、听觉、嗅觉、味觉。这就是词的形象色彩。本文试就词的形象色彩的类型,词的形象色彩与修辞的关系两个问题谈点看法。
关键词 形象色彩 动态 形态感 修辞 借代 比喻
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漫话水袖功
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作者 王化清 王双才 《晚霞》 2006年第3期42-42,共1页
我国传统戏曲中,无论帝王将相还是才子佳人,他们所穿的戏装(龙袍、官服、长衫、帔、开氅、褶子等)袖端常缀有一二尺或更长些的两片白绸子,因来回甩动时形似流水波纹,故名水袖。
关键词 水袖功 古代戏曲 艺术形式 形态感 情绪
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Antennal morphology of the cicada Meimuna mongolica (Distant) (Hemiptera: Cicadidae), with a deduction of its nymphal instars and discussion of the antennal morphological variations in relation to niche changes 被引量:2
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作者 李庆龙 魏琮 《Entomotaxonomia》 CSCD 北大核心 2013年第2期81-94,共14页
The morphology of antennal sensilla of both nymphs and adults in the cicada Meimuna mongolica (Distant) were studied. Four instars of M. mongolica (Distant) were preliminarily determined using Dyar's rule and a r... The morphology of antennal sensilla of both nymphs and adults in the cicada Meimuna mongolica (Distant) were studied. Four instars of M. mongolica (Distant) were preliminarily determined using Dyar's rule and a regression analysis of the head width of nymphs, combined with the comparative morphology of antennae of different stage nymphs and adults. The antennae of nymphs in different instars and adults show great morphological variations. The numbers, types and distribution of antennal sensilla in nymphs and adults of M. mongolica are significantly different, which should be closely related to the niche changes of the nymphs and adults, and provide implications for the development stages of this cicada. 展开更多
关键词 antennal sensilla MICROMORPHOLOGY nymphal instars ecology
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Predominance of Plasmodium malariae-falciparum Co-Infection by Molecular Speciation in Bangolan, North West Region of Cameroon 被引量:1
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作者 Olivia Afa Achonduh Aristid Herve Ekollo Mbange Atogho-Tiedeu Barbara Innocent Ali Mbulli Daniel Achinko Palmer Masumbe Netongo Wilfred Fon Mbacham 《Journal of Life Sciences》 2013年第6期599-606,共8页
Although microscopy still remains the gold standard for the diagnosis of malaria, rapid diagnostic tests (RDTs) and PCR assays have been shown to be sensitive and specific. Very few comparative studies have been rep... Although microscopy still remains the gold standard for the diagnosis of malaria, rapid diagnostic tests (RDTs) and PCR assays have been shown to be sensitive and specific. Very few comparative studies have been reported of the three diagnostic methods on the same samples in vulnerable groups. Microscopy, RDTs and PCR assays were used for detection and speciation of Plasmodium falciparum (P)'), Plasmodium malariae (Pm) and Plasmodium ovale (Po) in patients in a rice culture savanna ecotype. Fifty four children and 16 pregnant women presenting with a fever were recruited. Bloods collected was used for thin and thick smears, perform RDTs and spotted blood on filter paper for DNA extraction and performance of a PCR. Mean parasitaemia was 37,619.06 (+ 33,599.04) p/pL and 7,512.5 (+ 12,446.11) p/μL for children and pregnant women, respectively. A total of 87.14% were positive by microscopy, 85.71% by RDTs and 90% by PCR. Distribution of Plasmodium species as identified by PCR was 72.86% Pf/Pm, 11.43% Pf/Pm/Po and 5.43% Pm while 10% were negative. Cohen's Kappa value for PCR and RDTs was K = 0.75 (CI = 0.28-1.22) while PCR and microscopy was K = 0.64 (CI = 0.18-1.10). Malaria infection in Bangolan was mostly due to mix infection predominantly P. falciparum/P, malariae. 展开更多
关键词 Plasmodium sp. MICROSCOPY rapid diagnostic tests PCR children pregnant women.
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Near-source noise suppression of AMT by compressive sensing and mathematical morphology filtering 被引量:32
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作者 Li Guang Xiao Xiao +4 位作者 Tang Jing-Tian Li Jin Zhu Hui-Jie Zhou Cong Yan Fa-Bao 《Applied Geophysics》 SCIE CSCD 2017年第4期581-589,623,共10页
In deep mineral exploration, the acquisition of audio magnetotelluric (AMT) data is severely affected by ambient noise near the observation sites; This near-field noise restricts investigation depths. Mathematical m... In deep mineral exploration, the acquisition of audio magnetotelluric (AMT) data is severely affected by ambient noise near the observation sites; This near-field noise restricts investigation depths. Mathematical morphological filtering (MMF) proved effective in suppressing large-scale strong and variably shaped noise, typically low-frequency noise, but can not deal with pulse noise of AMT data. We combine compressive sensing and MMF. First we use MMF to suppress the large-scale strong ambient noise; second, we use the improved orthogonal match pursuit (IOMP) algorithm to remove the residual pulse noise. To remove the noise and protect the useful AMT signal, a redundant dictionary that matches with spikes and is insensitive to the useful signal is designed. Synthetic and field data from the Luzong field suggest that the proposed method suppresses the near-source noise and preserves the signal well; thus, better results are obtained that improve the output of either MMF or IOMP. 展开更多
关键词 Compressive sensing FILTERING magnetoiellurics signal processing noise
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5-Fluorouracil-related enhancement of adenoviral infection is Coxsackievirus-adenovirus receptor independent and associated with morphological changes in lipid membranes
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作者 Chiara Cabrele Mandy Vogel +5 位作者 Pompiliu Piso Markus Rentsch Josef Schroder Karl W Jauch Hans J Schlitt Alexander Beham 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第32期5168-5174,共7页
AIM: To evaluate the mechanism underlying the effects of 5-Fluorouracil (5-FU) on adenoviral infection. METHODS: Low and high Coxsackievirus-Adenovirus Receptor (CAR) expressing human colon carcinoma cell lines ... AIM: To evaluate the mechanism underlying the effects of 5-Fluorouracil (5-FU) on adenoviral infection. METHODS: Low and high Coxsackievirus-Adenovirus Receptor (CAR) expressing human colon carcinoma cell lines were treated with 5-FU and two El-deleted adenoviral constructs, one transferring GFP (Ad/CMV- GFP) the other bax (Ad/CEA-bax). The number of infected cells were monitored by GFP expression. To evaluate the effects of 5-FU in a receptor free system, Ad/GFP were encapsulated in liposomes and treated with 5-FU. Ad/GFP release was estimated with PCR and infection of 293 cells with the supernatant. Electron microscopy of the Ad5-GFP-liposome complex was made to investigate morphological changes of the liposomes after 5-FU. RESULTS: Infection rates of all cell lines increased from 50% to 98% with emerging 5-FU concentrations. The enhanced viral uptake was independent of the CAR expression. Additionally, 5-FU treated liposomes released 2-2.5 times more adenoviruses. Furthermore, 5-FU- treated liposomes appeared irregular and porous-like. CONCLUSION: adenoviral uptake is enhanced in the presence of 5-FU irrespective of CAR and is associated with morphological changes in membranes making the combination of both a promising option in gene therapy. 展开更多
关键词 5-FLUOROURACIL Coxsackievirus-adenovirusreceptor Adenoviral infection Gene therapy
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Reliable Analytic Strategy to Correlate the Morphological and Cytological Parameters on Lupinus termis L, against Fusarium oxysporum Infection
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作者 Ramadan Abd Elghany Mohamed Heba Hassan Elsalahy +2 位作者 Osama Abdel-Hafeez Al-Bedak Hoda Abd-EI-Fatah Mostafa Ahmed Nemmat Abd Elgawad Hussein 《Journal of Agricultural Science and Technology(A)》 2015年第7期585-600,共16页
Many analytic strategies have emerged to estimate plant responses to Fusarium wilt. The demand for fast and reliable method (diagnosis, prediction) to determine isolate strength accurately is not established yet. Ea... Many analytic strategies have emerged to estimate plant responses to Fusarium wilt. The demand for fast and reliable method (diagnosis, prediction) to determine isolate strength accurately is not established yet. Early determination of pathogen strength helps in plant medication. The aim of this study was to develop a faster strategy and method for early determination of fungal isolates strength in correlation to plant response. Till now, the scientists have no consensus on the most correlated parameters that could express wilt precisely. In this study, 30 isolates of Fusarium oxysporum isolated from Lupinus termis L. were used to provide an explicit image about the real strength of Fusarium isolates and its impact on the plant. Wilting percentage ranged from 26.67% to 93.33% of the infected plants depending on isolate virulence. Some of cellular, morphological and physical measurements were conducted on 8 out of 30 isolates, including root (length, fresh weight (FW) and dry weight (DW)), nodules (water content (WC), FW, DW), stem (height, WC, FW, DW), total leaves/plant (WC, FW, DW) and the fourth leaf (WC, FW, DW, leaf area, epidermal cell area, epidermal cell number, succulence). Hierarchical clustering was used to determine the variance between the isolates. Detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) were used to determine the most important growth parameters that could express wilting accurately. The CCA results showed that most of the measured parameters on the fourth leaf, except for leaf epidermal cell number, were highly and positively correlated to wilt. That makes these specific parameters valuable and sensitive for any changes in isolates strength. Accordingly, a mathematical model was created to be helpful in the quick determination of isolate strength and precise medication. 展开更多
关键词 F. oxysporum L. termis L. leaf area epidermal cell area water content linear and exponential decay models.
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Evaluation of Three-dimensional Urban Expansion: A Case Study of Yangzhou City, Jiangsu Province, China 被引量:11
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作者 QIN Jing FANG Chuanglin +2 位作者 WANG Yang LI Guangdong WANG Shaojian 《Chinese Geographical Science》 SCIE CSCD 2015年第2期224-236,共13页
With rapid urban development in China in the last two decades, the three-dimensional(3D) characteristic has been the main feature of urban morphology. However, the vast majority of researches of urban growth have focu... With rapid urban development in China in the last two decades, the three-dimensional(3D) characteristic has been the main feature of urban morphology. However, the vast majority of researches of urban growth have focused on the planar area(two-dimensional(2D)) expansion. Few studies have been conducted from a 3D perspective. In this paper, the 3D urban expansion of the Yangzhou City, Jiangsu Province, China from 2003 to 2012 was evaluated based on Geographical Information System(GIS) tools and high-resolution remote sensing images. Four indices, namely weighted average height of buildings, volume of buildings, 3D expansion intensity and 3D fractal dimension are used to quantify the 3D urban expansion. The weighted average height of buildings and the volume of buildings are used to illustrate the temporal change of the 3D urban morphology, while the other two indices are used to calculate the expansion intensity and the fractal dimension of the 3D urban morphology. The results show that the spatial distribution of the high-rise buildings in Yangzhou has significantly spread and the utilization of the 3D space of Yangzhou has become more efficient and intensive. The methods proposed in this paper laid a foundation for a wide range of study of 3D urban morphology changes. 展开更多
关键词 three-dimensional urban morphology high-resolution remote sensing image three-dimensional expansion three-dimen-sional fractal Yangzhou City China
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A method of remote sensing image water segmentation based on adaptive morphological elliptical structuring elements 被引量:1
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作者 WEN Hao-tian WANG Xiao-peng 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第3期236-243,共8页
The use of visible and infrared remote sensing images to calculate the water area is an effective means to grasp the basic situation of water resources,and water segmentation is the premise of statistics.Generally,the... The use of visible and infrared remote sensing images to calculate the water area is an effective means to grasp the basic situation of water resources,and water segmentation is the premise of statistics.Generally,the edge features of the water in the remote sensing images are complex.When the traditional morphology is used for image segmentation,it is easy to change the image edge and affect the accuracy of image segmentation because the fixed structuring elements are used to perform morphological operations on the image.To segment water in the remote sensing image accurately,a remote sensing image water segmentation method based on adaptive morphological elliptical structuring elements is proposed.Firstly,the eigenvalue and eigenvector of the image are estimated by linear structure tensor,and the elliptical structuring elements are constructed by the eigenvalue and eigenvector.Then adaptive morphological operations are defined,combining the close operation to eliminate the influence of dark detail noise on water without overstretching the water edge,so that the water edge can be maintained more accurately.Finally,on this basis,the water area can be segmented by gray slice.The experimental results show that the proposed method has higher segmentation accuracy and the average segmentation error is less than 1.43%. 展开更多
关键词 image processing adaptive morphology elliptical structuring elements remote sensing images water segmentation gray slice
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Micromorphology and Maturation of the Yellow Granules in the Hornet Gastral Cuticle
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作者 Marian Plotkin Stanislav Volynchik +2 位作者 Zahava Barkay David J.Bergman Jacob S.Ishay 《Zoological Research》 CAS CSCD 北大核心 2009年第1期65-73,共9页
The yellow granules in the gastral cuticle of the Oriental hornet Vespa oriental& (Hymenoptera, Vespinae) are located in yellow stripes. In the present study, we focus on the micromorphology and formation of the ye... The yellow granules in the gastral cuticle of the Oriental hornet Vespa oriental& (Hymenoptera, Vespinae) are located in yellow stripes. In the present study, we focus on the micromorphology and formation of the yellow granules from their inception to their spread in the regions which are destined to acquire a yellow color, The cuticle was observed with several methods of electron microscopy. The results showed that the yellow granules comprise a layer which is 20-25 μm thick, within the total cuticular thickness of 40-45 μm. In the mentioned regions one can see, from above, many apertures of about 0.5μm in diameter which extends into a peripheral photoreceptor cell. In each yellow granule, one discerns a myoid envelope inside which there are 9 fibrils arranged in a circle. Yellow granules maturation process involves infiltration of canals that give rise to the incipient ball-shaped primary granules which increase in number (as a result of continues budding off the walls of a canal) as the cuticle matures and transform into secondary barrel shaped granules, becoming elongated and then splitting into shorter barrels that fill up the entire area. Preliminary examinations have suggested liver-like function activity within the layer of yellow granules. 展开更多
关键词 MICROMORPHOLOGY Cuticle Yellow granules Peripheral photoreceptor Oriental hornet Vespa orientalis
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Generalized Negative Imaginary Lemma for Descriptor Systems 被引量:2
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作者 Mohamed A. Mabrok Abhijit G. Kallapur +1 位作者 Ian R. Petersen Alexander Lanzon 《Journal of Mechanics Engineering and Automation》 2012年第1期17-21,共5页
Flexible structure dynamics with collocated force actuators and position sensors lead to negative imaginary (NI) systems. In this paper, the authors study the extension of NI theory to descriptor systems. The author... Flexible structure dynamics with collocated force actuators and position sensors lead to negative imaginary (NI) systems. In this paper, the authors study the extension of NI theory to descriptor systems. The authors derive an NI lemma for descriptor systems. This is done by using the transformation from positive real (PR) system to NI system. Then, the Weierstrass Form transformation was involved to transform A and E matrices to be in a special form. An illustrative example is presented to support the result. Negative imaginary systems, positive real systems, descriptor systems, Negative imaginary lemma. 展开更多
关键词 Positive real negative imaginary descriptor systems.
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Reducing Numerical Oscillations through Modified Circuits for Inclusion of Frequency Influence in Transmission Line Representation
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作者 Leonardo S. Lessa Afonso J. Prado +2 位作者 Sdrgio Kurokawa Luiz F. Bovolato Jos6 Pissolato Filho 《Journal of Energy and Power Engineering》 2012年第11期1800-1808,共9页
In this article, a transmission line is represented by a cascade of n circuits using a single phase. It is analyzed what is the reasonable number of n circuits and the number of blocks composed by parallel resistor an... In this article, a transmission line is represented by a cascade of n circuits using a single phase. It is analyzed what is the reasonable number of n circuits and the number of blocks composed by parallel resistor and inductor in parallel for reduction of numerical oscillations. It is simulated the numerical routine with and without the effectof frequency in the longitudinal parameters. Initially, it is used to state variables and 7t circuits representing the transmission line composing a linear system which is solved by numerical routines based on the trapezoidal rule. The effect of frequency on the line is synthesized by resistors and inductors in parallel and this representation is analyzed in details. It is described as transmission lines and the frequency influence in these lines through the state variables. 展开更多
关键词 Electromagnetic transient EMTP mathematical model simulation transmission lines n circuit numeric method wavetraveling.
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Realizing the Box-counting Method for Calculating Fractal Dimension of Urban Form Based on Remote Sensing Image 被引量:7
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作者 GE Meiling LIN Qizhong 《Geo-Spatial Information Science》 2009年第4期265-270,共6页
In the research of fractal cities, the fractal dimension is very important. It is used to describe the fractal character of the city. The authors have designed two approaches to calculate the fractal dimension by the ... In the research of fractal cities, the fractal dimension is very important. It is used to describe the fractal character of the city. The authors have designed two approaches to calculate the fractal dimension by the box-counting method through an example of Beijing, which are called the vector method and the grid method, respectively. The former calculates the fractal dimension through an intersecting analysis in ArcView; and the latter is carried out by programming in Matlab. They are compared from three aspects: the calculating process, the limits in use, and the results. As a result, the conclusion is made that there are merits and faults on both methods, and they should be chosen to use properly in practical situation. 展开更多
关键词 fractal dimension box-counting method urban form remote sensing GIS MATLAB
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Land Use Effects on the Distribution and Speciation of Heavy Metals and Arsenic in Coastal Soils on Chongming Island in the Yangtze River Estuary, China 被引量:13
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作者 ZHENG Rong ZHAO Jiale +3 位作者 ZHOU Xiu MA Chao WANG Li GAO Xiaojiang 《Pedosphere》 SCIE CAS CSCD 2016年第1期74-84,共11页
The reclamation of tidal fiats has been one of the important approaches to replenish the arable lands in the coastal areas; pollution status of reclaimed soils has received wide attention recently, especially for the ... The reclamation of tidal fiats has been one of the important approaches to replenish the arable lands in the coastal areas; pollution status of reclaimed soils has received wide attention recently, especially for the study of heavy metals due to the relative high pollutant concentrations in wetlands. To understand the impact of land use change on heavy metal and arsenic (As) geochemistry by the reclamation of wetlands for agriculture, surface soils and soil profiles were collected from the agricultural land reclaimed in the 1990s and the intertidal flat wetland at Dongtan on Chongming Island in the Yangtze River Estuary, China. The soil samples were analyzed for total concentrations and chemical speciation of chromium (Cr), zinc (Zn), copper (Cu), lead (Pb), nickel (Ni), cadmium (Cd) and As using inductively coupled plasma mass spectrometry (ICP-MS). Results showed that soil properties (salinity, total organic carbon and grain-size distribution) and the concentrations of heavy metals and As in the soils differed under the different land use types. The conversion of wetland to forest had caused obvious losses of all the measured heavy metals. In paddy field and dryland with frequent cultivation, the concentrations of Cr, Zn, Cu, Ni and As were higher when compared to forest land which was disturbed rarely by human activities. Speciation analysis showed that Cr, Zn, Cu, Ni and As were predominated by the immobile residual fraction, while Pb and Cd showed relatively higher mobility. In general, metal (except Ni) and As mobility decreased in the following order: wetland 〉 dryland 〉 paddy field 〉 forest land, which suggested that the reclaimed soils had lower metal and As mobility than the intertidal fiat wetland. The results of this study contribute to a better understanding of the effects of land use on heavy metals and As in the reclaimed soils of the study area and other similar coastal areas. 展开更多
关键词 chemical fraction DRYLAND forest land intertidal flat paddy field reclaimed soils WETLAND
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Ultrahigh Resolution Fiber-Optic Quasi-Static Strain Sensors for Geophysical Research 被引量:2
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作者 Zuyuan HE Qingwen LIU Tomochika TOKUNAGA 《Photonic Sensors》 SCIE EI CAS 2013年第4期295-303,共9页
A review of our recent work on ultrahigh resolution optical fiber sensors in the quasi-static region is presented, and their applications in crustal deformation measurement are introduced. Geophysical research such as... A review of our recent work on ultrahigh resolution optical fiber sensors in the quasi-static region is presented, and their applications in crustal deformation measurement are introduced. Geophysical research such as studies on earthquake and volcano requires monitoring the earth's crustal deformation continuously with a strain resolution on the order of nano-strains (ne) in static to low frequency region. Optical fiber sensors are very attractive due to their unique advantages such as low cost, small size, and easy deployment. However, the resolution of conventional optical fiber strain sensors is far from satisfactory in the quasi-static domain. In this paper, several types of recently developed fiber-optic sensors with ultrahigh resolution in the quasi-static domain are introduced, including a fiber Bragg grating (FBG) sensor interrogated with a narrow linewidth tunable laser, an FBG based fiber Fabry-Perot interferometer (FFPI) sensor by using a phase modulation technique, and an FFPI sensor with a sideband interrogation technique. Quantificational analyses and field experimental results demonstrated that the FBG sensor can provide nano-order strain resolution. The sub-nano strain resolution was also achieved by the FFPI sensors in laboratory. Above achievements provide the basis to develop powerful fiber-optic tools for geophysical research on crustal deformation monitoring. 展开更多
关键词 Ultrahigh resolution fiber Bragg grating frequency modulation crustal deformation measurement
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The Many Sounds of Civilization
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作者 Emad El-Din Aysha 《Beijing Review》 2015年第32期48-48,共1页
British-American historian Bernard Lewis famously condemned Arab and Islamic civilization for not having a polyphonic sense of music,even accusing them of accepting totalitarian ideologies and regimes because of their... British-American historian Bernard Lewis famously condemned Arab and Islamic civilization for not having a polyphonic sense of music,even accusing them of accepting totalitarian ideologies and regimes because of their taste for"monophonic"music.That is,having one single singer with all the music following the ups and downs of his or her voice.Polyphonic music,by contrast,is when a piece of music has two or more independent melodies in it.As for the related notion of counterpoint,this is from many voices present in the chorus of a classical Greek drama and a reference to the coordination evident in choir singing. 展开更多
关键词 music downs taste drama singer evident notion civilization piece Greek
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