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基于机器视觉的番茄颜色分级方法的研究 被引量:5
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作者 刘宇飞 汤晓华 《机电产品开发与创新》 2013年第2期99-100,共2页
为提高番茄品质检测效率及分级精度,建立基于机器视觉理论的番茄视频在线检测理论模型,即将番茄图像采集、增强、滤波平滑去噪、分割后转换为HIS颜色模型。以国家标准(GB8852-88)定义番茄成熟度与色调(Hue)颜色特征的关系判定其成熟度等... 为提高番茄品质检测效率及分级精度,建立基于机器视觉理论的番茄视频在线检测理论模型,即将番茄图像采集、增强、滤波平滑去噪、分割后转换为HIS颜色模型。以国家标准(GB8852-88)定义番茄成熟度与色调(Hue)颜色特征的关系判定其成熟度等级,定义H分量等于零为红色。在此基础上开发视频检测系统,有效提取番茄表面颜色特征参量,实现高效、准确番茄品质线性分级。 展开更多
关键词 番茄品质 机器视觉 HIS模型 色调 成熟度等级 线性分级
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城市区域雨水地面径流模拟方法探讨 被引量:19
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作者 刘金星 邵卫云 《水利学报》 EI CSCD 北大核心 2006年第2期184-188,共5页
本文将水力学方法与水文学方法相结合,在用圣维南方程描述城市雨水地面径流过程的基础上引入全面汇流和部分汇流的概念,用线性叠加原理将均匀净雨强度下的坡面流理论应用于非均匀净雨强度下城市小区域地面径流模拟,从而建立了平原城市... 本文将水力学方法与水文学方法相结合,在用圣维南方程描述城市雨水地面径流过程的基础上引入全面汇流和部分汇流的概念,用线性叠加原理将均匀净雨强度下的坡面流理论应用于非均匀净雨强度下城市小区域地面径流模拟,从而建立了平原城市区域雨水地面径流过程模拟模型,并在进行流量过程线性叠加时采用3种净雨分割方式检验模型的模拟成果。最后将模拟结果与雨水管理模型SWMM进行对比,证明本文模型是较为合理和可行的,且具有一定的模拟精度和应用潜力。 展开更多
关键词 坡面流理论 线性分级叠加 降雨径流模型 模拟
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GPS及AVHRR资料在浅海潮间带测量中的应用 被引量:1
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作者 范德新 杨亚新 +1 位作者 尹成华 汤建国 《气象》 CSCD 北大核心 2001年第3期19-22,共4页
通过利用 GPS及渔探器实测 ,并进行潮位订正 ,获得南通浅海海域大量测点的高程资料 ;通过对多时相各通道 NOAA卫星照片进行筛选 ,挑选能反映浅海地貌的通道资料 ,从中读取各测点相对应的灰度值 ,在此基础上利用分级线性回归 ,建立不同... 通过利用 GPS及渔探器实测 ,并进行潮位订正 ,获得南通浅海海域大量测点的高程资料 ;通过对多时相各通道 NOAA卫星照片进行筛选 ,挑选能反映浅海地貌的通道资料 ,从中读取各测点相对应的灰度值 ,在此基础上利用分级线性回归 ,建立不同高程范围内的高程、灰度线性回归方程 ,确定不同高程的灰度阈值 ,从而测量出南通市浅海海域不同高程以上的潮间带面积、分布。 展开更多
关键词 GPS AVHRR资料 分级线性回归 潮间带 渔探器 测量 NOAA卫星
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考虑应力沿深度变化的饱和软黏土一维固结半解析解 被引量:1
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作者 王晋宝 童焯煜 +1 位作者 何博 许光映 《应用数学和力学》 CSCD 北大核心 2019年第10期1099-1108,共10页
针对饱和软黏土,结合引入弹壶元件改进的分数阶Kelvin模型,同时考虑土体内应力沿深度变化的特点,利用Laplace变换推导获得其一维固结半解析解.首先,通过与文献中的试验结果及文献中的理论结果对比,说明了该模型的有效性;其次,详细地分... 针对饱和软黏土,结合引入弹壶元件改进的分数阶Kelvin模型,同时考虑土体内应力沿深度变化的特点,利用Laplace变换推导获得其一维固结半解析解.首先,通过与文献中的试验结果及文献中的理论结果对比,说明了该模型的有效性;其次,详细地分析了不同分数阶阶数、不同总应力比以及不同分级线性加载等因素对饱和软黏土固结沉降以及孔隙水压力的影响,再现了饱和软黏土的固结沉降机理,以期为工程实践提供相关的理论基础. 展开更多
关键词 饱和软黏土 黏弹性 分数阶Kelvin模型 半解析解 分级线性加载
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Distribution of Vibrational Energy Levels of Protein Molecular Chains 被引量:2
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作者 PANGXiao-Feng CHENXiang-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第3期323-326,共4页
The distributions of the quantum vibrational energy levels of the protein molecular chain are found by the discretely nonlinear Schr?dinger equation appropriate to protein obtained from the Davydov theory. The results... The distributions of the quantum vibrational energy levels of the protein molecular chain are found by the discretely nonlinear Schr?dinger equation appropriate to protein obtained from the Davydov theory. The results calculated by this method are basically consistent with the experimental values. Furthermore, the energy spectra at high excited states have also been obtained for the molecular chain which is helpful in researching the properties of infrared absorption and Raman scattering of the protein molecules. 展开更多
关键词 vibrational energy levels nonlinear Schrodinger equation protein molecules
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Exact Solutions to Nonlinear Schr(?)dinger Equation and Higher-Order Nonlinear Schr(?)dinger Equation 被引量:1
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作者 REN Ji RUAN Hang-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期575-578,共4页
We study solutions of the nonlinear Schroedinger equation (NLSE) and higher-order nonlinear Sehroedinger equation (HONLSE) with variable coefficients. By considering all the higher-order effect of HONLSE as a new ... We study solutions of the nonlinear Schroedinger equation (NLSE) and higher-order nonlinear Sehroedinger equation (HONLSE) with variable coefficients. By considering all the higher-order effect of HONLSE as a new dependent variable, the NLSE and HONLSE can be changed into one equation. Using the generalized Lie group reduction method (CLGRM), the abundant solutions of NLSE and HONLSE are obtained. 展开更多
关键词 generalized Lie group reduction method nonlinear Schroedinger equation higher order nonlin ear Schroedinger equation
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Hierarchical Linear Model Approach to the Determinants of Activities of Daily Living of Chinese Oldest Old at Both Individual and Regional levels
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作者 Yin Deting Lu Jiehua 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第4期31-41,共11页
Based on the Chinese longitudinal healthy longevity survey conducted in 2002, this paper uses hierarchical linear model (HLM) to make an approach to the possible determinants of activities of daily living (ADL) of Chi... Based on the Chinese longitudinal healthy longevity survey conducted in 2002, this paper uses hierarchical linear model (HLM) to make an approach to the possible determinants of activities of daily living (ADL) of Chinese oldest old (aged 80 and above) by combining both individual and provincial level factors. The descriptive analysis shows that there is a great differ- ential in ADL by province among Chinese oldest old. The findings turn out that there does exist a significant differential in ADL between oldest old and young old, and that there is also a great differential in ADL by province among Chinese oldest old. The HLM demonstrates that comorbidity, age, cognitive impairment, visual impairment, and emotion could be the most important indi- vidual factors while natural environment, medical facilities, type of staple food and poverty rate in urban areas are the most sig- nificantly regional determinants of ADL of oldest old. The find- ings imply that future actions should not only be taken at individ- ual level, but also at regional level in order to achieve the goal of a healthy aging society in China. 展开更多
关键词 ADL HLM determinants oldest old China
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Stability analysis of linear multistep methods for neutral delay differential equations
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作者 S K JAFFER 刘明珠 丁效华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第2期168-170,共3页
The stability analysis of linear multistep (LM) methods is carried out under Kreiss resolvent condition when they are applied to neutral delay differential equations of the form y′(t)=ay(t)+by(t-τ)+ cy′(t- τ) y(t)... The stability analysis of linear multistep (LM) methods is carried out under Kreiss resolvent condition when they are applied to neutral delay differential equations of the form y′(t)=ay(t)+by(t-τ)+ cy′(t- τ) y(t)=g(t) -τ≤t≤0 with τ>0 and a, b and c∈, and it is proved that the ‖B n‖ is suitably bounded, where B is the companion matrix. 展开更多
关键词 linear multistep methods neutral differential equations Kreiss resolvent condition
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3D Nonlinear Analysis of the Preloading Filling Spiral Case of the Jinping-I Hydropower Station
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作者 XING Xiang-lin 《International Journal of Technology Management》 2014年第9期63-68,共6页
In consideration of the contact between the steel spiral casing and the peripheral reinforced concrete, a nonlinear analysis for the combined bearing structure of the JinPing-I preloading filling spiral case has been ... In consideration of the contact between the steel spiral casing and the peripheral reinforced concrete, a nonlinear analysis for the combined bearing structure of the JinPing-I preloading filling spiral case has been made with ANSYS. Contrasts of the stress of the reinforcing bars, the biggest width of the crack and the outspread section of the crack has been made with the different parameters of preloading pressure and reinforcement scheme, resulting in a reasonable preloading pressure and reinforcement scheme. This conclusion has been applied to the spiral casing of JinPing-I hydropower station. 展开更多
关键词 hydraulic structures structure analysis 3D finite element preloading filling spiral casing
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New Integrable Decomposition of Super AKNS Equation
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作者 季杰 董亚娟 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第11期803-808,共6页
In this paper, a new 7×7 matrix spectral problem, which is associated with the super AKNS equation isconstructed.With the use of the binary nonlinearization method, a new integrable decomposition of the super AKN... In this paper, a new 7×7 matrix spectral problem, which is associated with the super AKNS equation isconstructed.With the use of the binary nonlinearization method, a new integrable decomposition of the super AKNSequation is presented. 展开更多
关键词 spectral-problem integrable decomposition super AKNS equation
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A Forward-Secure Multi-Receiver Signcryption Scheme
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作者 Zhimin Yu Zhengjun Jing +1 位作者 Hua Yang Chunsheng Gu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第5期53-61,共9页
In order to protect historical ciphertext when the private key leaked in the broadcasting system,the forward-secure multi-receiver signcryption scheme is designed based on the generic graded multilinear mapping encodi... In order to protect historical ciphertext when the private key leaked in the broadcasting system,the forward-secure multi-receiver signcryption scheme is designed based on the generic graded multilinear mapping encoding structure,which effectively prevents illegal access from intruder to the ciphertext in the past time period when the private key in current time period is revealed.Through the generalization of the existing multilinear mapping encoding system,it proposes the generic graded multilinear mapping encoding structure and the generic graded decision Diffie-Hellman problem.Because of the generic graded multilinear mapping encoding system adopted,almost all candidate multilinear mapping encoding systems can automatically adapt to our scheme.Under the assumption of generic graded decision Diffie-Hellman problem,it has proved that the scheme has the information confidentiality and unforgeability in the current time period.After putting forward the security model of forward-secure multi-receiver signcryption scheme,and under the assumption of generic graded decision Diffie-Hellman problem,it has proved that the scheme has the message forward-confidentiality and forward-unforgeability.Compared with other forward-secure public key encryption schemes,the relationship between our scheme and time periods is sub-linear,so it is less complex. 展开更多
关键词 multilinear mapping forward-secure multi-receiver signcryption CONFIDENTIALITY UNFORGEABILITY
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GLOBAL EXISTENCE OF WEAKLY DISCONTIN UOUS SOLUTIONS TO THE CAUCHY PROBLEM WITH A KIND OF NON-SMOOTH INITIAL DATA FOR QUASILINEAR HYPERBOLIC SYSTEMS 被引量:10
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作者 LITATSIEN WANGLIBIN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2004年第3期319-334,共16页
The authors consider the Cauchy problem with a kind of non-smooth initial data for quasilinear hyperbolic systems and obtain a necessary and sufficient condition to guarantee the existence and uniqueness of global wea... The authors consider the Cauchy problem with a kind of non-smooth initial data for quasilinear hyperbolic systems and obtain a necessary and sufficient condition to guarantee the existence and uniqueness of global weakly discontinuous solution. 展开更多
关键词 Quasilinear hyperbolic system Cauchy problem Global weakly discontinuous solution Weakly linear degeneracy
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An Improved Nonlinear Multistage Switch System of Microbial Fermentation Process in Fed-Batch Culture
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作者 WANG Lei FENG Enmin 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第3期580-591,共12页
This paper considers the fed-batch culture in microbial fermentation process, which consists of batch and continuous culture. The goal is to explore the properties of a novel model which can describe the characteristi... This paper considers the fed-batch culture in microbial fermentation process, which consists of batch and continuous culture. The goal is to explore the properties of a novel model which can describe the characteristics of multistage for the population growth of microorganisms in nonlinear switch dynamic system. The improved model is developed based on the experimental data to describe the delayed, developmental and stationary stages well for the phases of batch culture. Then the existence, uniqueness and boundedness of solutions to the nonlinear multistage switch system and the Lipschitz continuity and differentiability of solutions with respect to the initial state is discussed as well. Finally, a numerical simulation is employed for the nonlinear multistage switch system. 展开更多
关键词 Bioconversion fed-batch culture Klebsiella pneumoniae nonlinear multistage switch system.
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