出行行为视角下土地功能混合测度方法研究

土地功能混合是当代城市规划的重要理念,其测度方法一直是研究的热点和难点。文章聚焦于土地功能混合对出行行为的影响,通过归纳现有国内外相关研究中针对土地功能混合的主流测度方法,梳理出一套常用的测度方法体系,包括测度的一般步骤、功能的分类及选取依据、研究范围的确定依据、常用的数据类型、常用的量化指标和数据收集统计方式。文章认为土地功能混合具有三个特征:多样性、邻近性、兼容性,需对应到数量维度、空间维度和关系维度进行量化分析,难以使用一个综合的指标表示所有特征。

模糊集方法在检索评价混合测度中的应用

从传统的评价信息检索系统的查全率和查准率出发,考虑相关性是一个模糊概念,对信息检索评价中的混合测度进行研究。

广义毕达哥拉斯犹豫模糊集混合加权距离测度及决策应用

在毕达哥拉斯犹豫模糊数的距离基础上,定义毕达哥拉斯犹豫模糊集(Pythagorean hesitant fussy set,PHFS)的加权距离测度和有序加权距离测度,在兼顾属性权重和位置权重的基础上,提出广义PHFS混合加权距离测度(D_(GPHFHWA)),并研究其性质和特殊形式。针对属性值为毕达哥拉斯犹豫模糊数且属性权重未知的多属性决策问题,利用毕达哥拉斯犹豫模糊指数熵确定属性权重,并结合逼近理想解排序法(technique for order preference by similarity to an ideal solution,TOPSIS)思想,提出基于D_(GPHFHWA)测度的决策方法。最后,通过实例验证所提方法是有效、合理的。

混合导数测度的性质及其应用

本文讨论了三维Bernoulli分布与正态分布在混合导数测度下的可压缩性的问题,导出了这两个分布在混合导数测度下可压缩的充分必要条件,同时利用混合导数测度,我们在适当条件下解决了[1]提到的无向图的Gibbs分解问题。

混合泊松随机测度的定义与构造

随机过程的具体刻划在金融上有重要应用。混合泊松随机测度正是其一个精确刻划 ,记录值可形成泊松随机测度 ,而记录时间可用泊松随机过程很好地逼近。前人给出了泊松随机测度的经典结果。在此基础上运用测度论典型手法及拉普拉斯泛函 ,得到混合泊松随机测度的结论。不仅给出了混合泊松随机测度的定义 :N是E上的点过程 ,如果在给定Λ =λ条件下 ,N是具有均值测度的泊松随机测度 ,则称N为混合泊松随机测度。而且得到混合泊松随机测度的构造与存在唯一性定理。

一个关于混合锥体积测度的子空间集中不等式

子空间集中不等式是关于测度的一个重要不等式,在凸几何分析中有很多的运用.本文研究了关于测度的子空间集中不等式,主要利用函数f_(K,ξ)通过Lipschitz区域中Lipschitz向量场的Gauss-Green散度定理得到了一个关于混合锥体积测度的等式,进而通过这个等式得到了混合锥体积测度的子空间集中不等式.

异质性视角下绿色转型绩效评价与提升研究

从"经济—资源—环境—社会"系统分析的思路出发,结合混合评价、全局分析和共同前沿技术构建绿色转型绩效的测度模型。基于二十国集团(G20)2000~2015年面板数据的实证研究表明:发达国家组绿色转型绩效最高,处于绿色生产技术的前沿和领先地位,并实现了技术与管理的"双轮驱动";以中国为代表的金砖国家组的绿色转型绩效次之,其绩效增长主要受益于管理制度的优化,但出现了技术退步现象;其他发展中国家组的绿色增长具有波动性,技术创新带来的积极作用仍不能缩小其与最优前沿绿色技术的差距。根据对"追赶型"、"创新型"和"领先型"国家的分析,进一步提出各国实现绿色转型的异质性提升策略。

改进优势度决策法及其排序方法

为进一步分析现有决策方案中存在的问题,提出解决混合测度决策问题的优势度决策法。根据实际决策情况给出一组优势相关的定义,对优势度求取方法进行改进,对其互补性和一致性进行有效性验证。对改进方法的排序向量、优势向量以及比较向量的特征进行研究,与线性加权法和理想点法做对比分析,分析结果表明,该方法计算量小、精确性高、通用性好。实例分析结果表明了改进优势度算法的有效性。

黑龙江垦区耕地利用生态效率及其内部协调性

基于耕地利用生态效率的内涵界定,运用DEA效率混合测度模型和协调发展度模型,分析2001 2016黑龙江垦区耕地利用生态效率及其非效率来源,探究耕地利用生态效率的内部协调性.研究表明:2001 2016年研究区耕地利用生态效率呈波动上升趋势,变化幅度不大,各管理局耕地利用生态效率差异明显;耕地利用效率损失的主要原因为投入非效率、社会产出非效率和环境产出非效率,且投入非效率普遍高于社会产出非效率和环境产出非效率,耕地投入冗余对耕地利用效率的负向影响最大;耕地利用经济和社会效率相对于环境效率滞后,是影响耕地利用生态效率内部协调性的主要原因.认为耕地利用生态效率是耕地利用经济、社会和环境效率的综合体现,并从内生性角度分析耕地利用非效率来源及其变化趋势,为提高耕地利用效率提供有效指导,即通过优化研究区耕地投入结构,减少耕地投入冗余,提升其耕地利用经济和社会效率,以实现耕地利用经济、社会和环境效率的协调发展.

基于连续投影算法提取特征波长的空中目标参考光谱选取

空中目标在相对稳定的状态下具有确定的光谱辐射特性,因而可以利用光谱达到识别其型号的目的。首先,通过建立空中目标光谱辐射特性计算模型,获得了其归一化光谱辐射亮度数据。然后,利用连续投影算法对光谱进行特征波长提取,在保留一定精度的同时有效减少了所需数据量。最后,使用区分能力更强的混合光谱相似性测度SID (TAN)匹配光谱,研究在3~5μm波段和8~14μm波段两个大气窗口内,光谱辐射特性在不同飞行高度和飞行时间下的变化规律。结果表明:飞行高度对光谱辐射特性的影响大于飞行时间;3~5μm波段的变化较8~14μm波段明显。因此在建立光谱数据库时,为了提高识别的准确率,相对于8~14μm波段,3~5μm波段更需要考虑不同因素对光谱辐射特性的影响;相对于飞行时间,应尽可能多地选取不同飞行高度下的光谱作为参考光谱。

一种改进的偏二叉树孪生支持向量机算法及其应用

针对二叉树分类性能受其层次结构影响较大的问题,提出了一种改进的偏二叉树孪生支持向量机多分类算法;该算法定义了一种基于加权样本类内距离和类间距离的混合分离性测度β,根据β的大小构造出合理层次结构的偏二叉树孪生支持向量机分类器;通过UCI数据集,验证了改进算法相较于其它SVM多分类算法的优越性;以风电机组齿轮箱故障诊断作为研究对象,基于时频联合方法提取其故障特征,应用改进的偏二叉树孪生支持向量机算法实现了对齿轮箱故障的准确识别。

Prediction of Flash Point Temperature of Organic Compounds Using a Hybrid Method of Group Contribution ＋ Neural Network ＋ Particle Swarm Optimization

The flash points of organic compounds were estimated using a hybrid method that includes a simple group contribution method (GCM) implemented in an artificial neural network (ANN) with particle swarm optimization (PSO). Different topologies of a multilayer neural network were studied and the optimum architecture was determined. Property data of 350 compounds were used for training the network. To discriminate different substances the molecular structures defined by the concept of the classical group contribution method were given as input variables. The capabilities of the network were tested with 155 substances not considered in the training step. The study shows that the proposed GCM+ANN+PSO method represent an excellent alternative for the estimation of flash points of organic compounds with acceptable accuracy (AARD = 1.8%; AAE = 6.2 K).

Measurement and correlation of solubility of trimethylolethane in different pure solvents and binary mixtures

The solubilities of trimethylolethane in butanol,methyl acetate,ethyl acetate as well as in mixed solvents of(methanol+ethyl acetate) and(ethanol+ethyl acetate) were measured with the gravimetric method in the temperature range from 283.15 K to 318.15 K under atmosphere pressure.The experiment results showed that the solubility of trimethylolethane increased with the temperature,or along with the concentration of methanol or ethanol in the solvents of(methanol+ethyl acetate) and(ethanol + ethyl acetate).In addition,the experiment values were correlated by the van't Hoff equation,Modi fied Apelblat Equation,λh Equation,CNIBS/R-K equation and Jouyban–Acree Model.The Modi fied Apelblat Equation provided the best fitting results of the solubility data of TME in the pure solvents while the CNIBS/R-K model showed the best estimation of the solubility in the binary solvent mixtures.Furthermore,the density functional theory(DFT) calculations showed that solubility in different solvents related to the strength of the interaction between the trimethylolethane and the solvent molecules.Finally,the standard molar enthalpy and molar entropy of trimethylolethane during the dissolving process was also calculated by Modi fied Apelblat equation in this work.

An Aircraft Trajectory Anomaly Detection Method Based on Deep Mixture Density Network

The timely and accurately detection of abnormal aircraft trajectory is critical to improving flight safety.However,the existing anomaly detection methods based on machine learning cannot well characterize the features of aircraft trajectories.Low anomaly detection accuracy still exists due to the high-dimensionality,heterogeneity and temporality of flight trajectory data.To this end,this paper proposes an abnormal trajectory detection method based on the deep mixture density network(DMDN)to detect flights with unusual data patterns and evaluate flight trajectory safety.The technique consists of two components:Utilization of the deep long short-term memory(LSTM)network to encode features of flight trajectories effectively,and parameterization of the statistical properties of flight trajectory using the Gaussian mixture model(GMM).Experiment results on Guangzhou Baiyun International Airport terminal airspace show that the proposed method can effectively capture the statistical patterns of aircraft trajectories.The model can detect abnormal flights with elevated risks and its performance is superior to two mainstream methods.The proposed model can be used as an assistant decision-making tool for air traffic controllers.

Experimental study on the effects of big particles physical characteristics on the hydraulic transport inside a horizontal pipe

This paper presents an experimental study of the physical characteristic effects of large particles on hydraulic transport in a horizontal pipe.The particles are spherical and are large with respect to the diameter of the pipe(8%,10%,16% and 25%).Experiments were done to test the important parameters in solid transport(pressure,velocity,etc.).As a result,the relationship between the pressure gradient forces and the mixture velocity was substantially different from the pure liquid flow.However,in a single-phase flow a monotonous behavior of the pressure drop curve is observed,and the curve of the solid particle flow attains its minimum at the critical velocity.The regimes are characterized with differential pressure measurements and visualizations.

Measurement and Correlation of Solubility of Ethyl Nitrite in Mixed Solvent

An experimental apparatus was used to measure the solubility of ethyl nitrite in mixed solvents under the lower pressure and higher temperature. The solubilities of ethyl nitrite in mixed solvents of ethanol-water at 15℃-40℃ and ethanol-diethyl oxalate at 20℃--40℃ were determined. A Henry constant model has been improved, and the interaction parameters have been fitted from experimental data. The calculation results have been compared with experimental data； the results obtained are satisfactory.

Decadal variability of chlorophyll α in the South China Sea: a possible mechanism

Four climatologies on a monthly scale (January, April, May and November) of chlorophyll a within the South China Sea (SCS) were calculated using a Coastal Zone Color Scanner (CZCS) (1979-1983) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) (1998-2002). We analyzed decadal variability of chlorophyll a by comparing the products of the two observation periods. The relationships of variability in chlorophyll a with sea surface wind speed (SSW), sea surface temperature (SST), wind stress (WS), and mixed layer depth (MLD) were determined. The results indicate that there is obvious chlorophyll a decadal variability in the SCS. The decadal chlorophyll a presents distinct seasonal variability in characteristics, which may be as a result of various different dynamic processes. The negative chlorophyll a concentration anomaly in January was associated with the warming of SST and a shallower MLD. Generally, there were higher chlorophyll a concentrations in spring during the SeaWiFS period compared with the CZCS period. However, the chlorophyll a concentration exhibits some regional differences during this season, leading to an explanation being difficult. The deepened MLD may have contributed to the positive chlorophyll a concentration anomalies from the northwestern Luzon Island to the northeastern region of Vietnam during April and May. The increases of chlorophyll a concentration in northwestern Borneo during May may be because the stronger SSW and higher WS produce a deeper mixed layer and convective mixing, leading to high levels of nutrient concentrations. The higher chlorophyll a off southeastern Vietnam may be associated with the advective transport of the colder water extending from the Karimata Strait to southeastern Vietnam.

Production of a Mathematic Equation Using Statistical Data for the Determination of Kinematic Viscosity in Blends of Diesel Fuel with Biodiesel

In this paper, the authors try to export an equation which describes the variation of kinematic viscosity in blends of diesel fuel with biodiesel. Using specific volume of these blends, the authors determine kinematic viscosity via method ASTM D 445-06 using a capillary glass viscometer in order to study the contribution of quantity of biodiesel and convert the statistical data into mathematic relation as a specific formula, attempting to achieve an empirical evaluation. Trying to accomplish this, the authors studied the way how the values of variables are changed and whether a relation exists using dispersion diagrams. From the graphic depiction, the authors realized that the relation is linear and they proceeded to regression analysis. The analysis extracted the conclusion that the relation was strong and the values of the dependent variable kinematic viscosity was depended on a large percentage of the values of the mixture of fuels.

Tides and Turbulent Mixing in the North of Taiwan Island

Microstructure and hydrological profiles were collected along two cross-shelf sections from the deep slope to the shallow water in the north of Taiwan Island in the summer of 2006.While the tidal currents on the shelf were dominated by the barotropic tide with the current ellipse stretched across the shelf,significant internal tides were observed on the slope.The depth-mean turbulent kinetic energy(TKE)dissipation rate on the shelf was 10^-6W kg^-1,corresponding to a diapycnal diffusivity of 10^-2 m^2s^-1.The depth-mean TKE dissipation rate on the slope was 1×10^-7 Wkg^-1,with diapycnal diffusivity of 3×10^-4m^2s^-1.The shear instability associated with internal tides largely contributed to the TKE dissipation rate on the slope from the surface to 150 m,while the enhanced turbulence on the shelf was dominated by tidal or residual current dissipations caused by friction in the thick bottom boundary layer(BBL).In the BBL,the Ekman currents associated with the northeastward Taiwan Warm Current were identified,showing a near-bottom velocity spiral,which agreed well with the analytical bottom Ekman solution.

Gradient Step Method to Predict the Ozone Solubility in Water

In this work it presents a strategy to obtain the ozone solubility in water by gradient step method. In this methodology, the ozone in mixture with oxygen is bubbling in a reactor with distilled water at 21℃ and pH 7. The ozone concentration on gas phase is continually increased after the saturation is reached. The method proposed is faster than conventional method （isocratic method）. The solubility from the gradient method is compared with that values obtained from correlations founded in the literature.