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一种间接估计阿根廷城市湿地海狸鼠多度的方法(英文)
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作者 María José CORRIALE Santiago Manuel ARIAS +1 位作者 Roberto Fabián B Gustavo PORINI 《动物学报》 SCIE CAS CSCD 北大核心 2008年第1期164-168,共5页
我们设计了一种利用洞穴大小和空间散布来估计海狸鼠(Myocastor coypus)绝对数量的间接方法,并使用个体移除法对绝对数量的估计进行了检验。利用参数相关和效能检验对这两种方法的方程式斜率差异进行了检验,两者间存在高度正相关(r=0... 我们设计了一种利用洞穴大小和空间散布来估计海狸鼠(Myocastor coypus)绝对数量的间接方法,并使用个体移除法对绝对数量的估计进行了检验。利用参数相关和效能检验对这两种方法的方程式斜率差异进行了检验,两者间存在高度正相关(r=0·963 ,P=0·002)。以洞穴大小和空间散布估计海狸鼠数量的方程斜率与1·0没有显著性差异(P=0·05) ,其差异检出效能为93 %。因此,利用洞穴大小和空间散布估计海狸鼠绝对数量的这种间接数量估计方法既不影响动物又不扰乱生境,其结果精确且易于实施。 展开更多
关键词 多度 阿根廷 间接数量估计法 海狸鼠 城市湿地
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面向卫浴产品设计的人体沐浴温觉研究 被引量:2
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作者 倪敏娜 孙志宏 +1 位作者 彭础琦 黄思哲 《东华大学学报(自然科学版)》 CSCD 北大核心 2017年第4期603-606,616,共5页
为了提高现代卫浴产品的使用性能和用户舒适度,在特定试验条件下,从心理物理学方面入手,采用数量估计和统计分析等方法,对用户沐浴舒适水温范围的测量、静动态水的温度感知对比、实际水温与水温感受值之间的关系进行了试验设计和定量分... 为了提高现代卫浴产品的使用性能和用户舒适度,在特定试验条件下,从心理物理学方面入手,采用数量估计和统计分析等方法,对用户沐浴舒适水温范围的测量、静动态水的温度感知对比、实际水温与水温感受值之间的关系进行了试验设计和定量分析,确认了相关函数关系式.通过史蒂文斯定律验证试验结果,证实了函数关系式的有效性. 展开更多
关键词 卫浴产品 沐浴温觉 史蒂文斯定律 数量估计法
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高校教师负性行为量表的编制
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作者 郑旭钊 范如冰 杨扉 《心理学进展》 2022年第11期3691-3698,共8页
教师在与学生互动的过程中可能会出现让学生感到消极的行为而不自知,从而影响师生关系与教学效果,因此编制量表以便高校教师自查负性行为。首先通过文献分析与一对一访谈总结出师生互动场景;再通过问卷收集高校教师负性行为,再通过四轮... 教师在与学生互动的过程中可能会出现让学生感到消极的行为而不自知,从而影响师生关系与教学效果,因此编制量表以便高校教师自查负性行为。首先通过文献分析与一对一访谈总结出师生互动场景;再通过问卷收集高校教师负性行为,再通过四轮预试以及评估和修订形成最终问卷,再通过一对一监督被试填写E-prime程序得到数据,最终问卷采用数量估计法。基于数量估计法在实践中遇到的困难,对其进行了相应的改进,分析最终问卷数据后得到高校教师负性行为量表。信度和效度符合心理测量学要求,可用于高校教师负性行为的初步施测。 展开更多
关键词 教师负性行为 量表编制 数量估计法
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Parameter identification and pressure control of dynamic system in shield tunneling using least squares method 被引量:10
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作者 LI Shou-ju CAO Li-juan +1 位作者 SHANGGUAN Zi-chang LIU Bo 《Journal of Coal Science & Engineering(China)》 2010年第3期256-261,共6页
An estimation approach using least squares method was presented for identificationof model parameters of pressure control in shield tunneling.The state equation ofthe pressure control system for shield tunneling was a... An estimation approach using least squares method was presented for identificationof model parameters of pressure control in shield tunneling.The state equation ofthe pressure control system for shield tunneling was analytically derived based on themass equilibrium principle that the entry mass of the pressure chamber from cutting headwas equal to excluding mass from the screw conveyor.The randomly observed noise wasnumerically simulated and mixed to simulated observation values of system responses.The numerical simulation shows that the state equation of the pressure control system forshield tunneling is reasonable and the proposed estimation approach is effective even ifthe random observation noise exists.The robustness of the controlling procedure is validatedby numerical simulation results. 展开更多
关键词 parameter identification least squares method state equation shield tunneling
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Semiparametric Regression and Model Refining 被引量:13
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作者 SUN Haiyan WU Yun 《Geo-Spatial Information Science》 2002年第4期10-13,共4页
This paper presents a semiparametric adjustment method suitable for general cases.Assuming that the regularizer matrix is positive definite,the calculation method is discussed and the corresponding formulae are presen... This paper presents a semiparametric adjustment method suitable for general cases.Assuming that the regularizer matrix is positive definite,the calculation method is discussed and the corresponding formulae are presented.Finally,a simulated adjustment problem is constructed to explain the method given in this paper.The results from the semiparametric model and G_M model are compared.The results demonstrate that the model errors or the systematic errors of the observations can be detected correctly with the semiparametric estimate method. 展开更多
关键词 model error systematric error semiparametric regression model refine regularizer matrix smoothing parameter
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Blind Estimation of Long Code DSSS Signal Based On Subspace Tracking 被引量:1
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作者 Ma Chao Zhang Limin Wang Jianxiong 《International Journal of Technology Management》 2013年第1期80-83,共4页
Aiming at solving the blind estimation problem of dispreading spectrum sequence under low SNR, a spread-spectrum estimation algorithm based subspace tracking is studied in this paper. This method avoids the direct eig... Aiming at solving the blind estimation problem of dispreading spectrum sequence under low SNR, a spread-spectrum estimation algorithm based subspace tracking is studied in this paper. This method avoids the direct eigen decomposition, using the sliding window technique to obtain the code synchronization, then use segmentation subspace tracking method estimate spreading sequence and splice in a certain order to achieve pseudo-code blind estimation. The results show that the algorithm can complete the accurate estimation of PN code sequence in low SNR conditions, reduce the amount of data storage and be easy hardware implementation 展开更多
关键词 DSSS blinding estimation of spread-spectrum waveform subspace tracking long code
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Estimation Method of Center of Inertia Frequency Based on Phasor Measurement Data
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作者 Takuhei Hashiguchi Masayuki Watanabe +4 位作者 Tadahiro Goda Yasunori Mitani Osamu Saeki Masahide Hojo Hiroyuki Ukai 《Journal of Energy and Power Engineering》 2012年第3期434-445,共12页
In the world, recent increased disturbances, congestion management problems, and increases of complexity in operating power systems have brought the need for integrations and improvements of power systems. Advanced ap... In the world, recent increased disturbances, congestion management problems, and increases of complexity in operating power systems have brought the need for integrations and improvements of power systems. Advanced applications in WAMPAC (wide area monitoring, protection, and control) systems provide a cost effective solution to improve system planning, operation, maintenance, and energy trading. Synchronized measurement technology and the application are an important element of WAMPAC. In addition, PMUs (phasor measurement units) are the most accurate and advanced time-synchronized technology available for WAMPAC application. Therefore, the original measurement system of PMUs has been constructed in Japan. This paper describes the estimation method of a center of inertia frequency by applying actual measurement data. The application of this method enables us to extract power system oscillations from measurement data appropriately. Moreover, this proposed method will help to the clarification of power system dynamics and this application will make it possible to realize the monitoring of power system oscillations associated with the power system stability. 展开更多
关键词 Phasor measurement unit power system oscillations signal processing center of inertia frequency monitoring.
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Model-Based Integrated Methods for Quantitative Estimation of Soil Salinity from Hyperspectral Remote Sensing Data:A Case Study of Selected South African Soils 被引量:31
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作者 Z. E. MASHIMBYE M. A. CHO +3 位作者 J. P. NELL W. P. DE CLERCQ A. VAN NIEKERK D. P. TURNER 《Pedosphere》 SCIE CAS CSCD 2012年第5期640-649,共10页
Soil salinization is a land degradation process that leads to reduced agricultural yields. This study investigated the method that can best predict electrical conductivity (EC) in dry soils using individual bands, a n... Soil salinization is a land degradation process that leads to reduced agricultural yields. This study investigated the method that can best predict electrical conductivity (EC) in dry soils using individual bands, a normalized difference salinity index (NDSI), partial least squares regression (PLSR), and bagging PLSR. Soil spectral reflectance of dried, ground, and sieved soil samples containing varying amounts of EC was measured using an ASD FieldSpec spectrometer in a darkroom. Predictive models were computed using a training dataset. An independent validation dataset was used to validate the models. The results showed that good predictions could be made based on bagging PLSR using first derivative reflectance (validation R2 = 0.85), PLSR using untransformed reflectance (validation R2 = 0.70), NDSI (validation R2 = 0.65), and the untransformed individual band at 2257 nm (validation R2 = 0.60) predictive models. These suggested the potential of mapping soil salinity using airborne and/or satellite hyperspectral data during dry seasons. 展开更多
关键词 electrical conductivity land degradation partial least squares regression salinity index spectral reflectance
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Progress on quantitative assessment of the impacts of climate change and human activities on cropland change 被引量:4
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作者 石晓丽 王卫 史文娇 《Journal of Geographical Sciences》 SCIE CSCD 2016年第3期339-354,共16页
It is important to study the contributions of climate change and human activities to cropland changes in the fields of both climate change and land use change. Relationships between cropland changes and driving forces... It is important to study the contributions of climate change and human activities to cropland changes in the fields of both climate change and land use change. Relationships between cropland changes and driving forces were qualitatively studied in most of the previous researches. However, the quantitative assessments of the contributions of climate change and human activities to cropland changes are needed to be explored for a better understanding of the dynamics of land use changes. We systematically reviewed the methods of identifying the contributions of climate change and human activities to cropland changes at quantitative aspects, including model analysis, mathematical statistical method, framework analysis, index assessment and difference comparison. Progress of the previous researches on quantitative evaluation of the contributions was introduced. Then we discussed four defects in the assessment of the contributions of climate change and human activities. For example, the methods were lack of comprehensiveness, and the data need to be more accurate and abundant. In addition, the scale was single and the explanations were biased. Moreover, we concluded a clue about quantitative approach to assess the contributions from synthetically aspect to specific driving forces. Finally, the solutions of the future researches on data, scale and explanation were proposed. 展开更多
关键词 climate change human activities CONTRIBUTIONS QUANTITATIVE cropland pattern
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