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PyLUR: Efficient software for land use regression modeling the spatial distribution of air pollutants

Xuying Ma, Ian Longley, Jennifer Salmond, Jay Gao

《环境科学与工程前沿（英文）》 2020年第14卷第3期 doi: 10.1007/s11783-020-1221-5

摘要： PyLUR comprises four modules for developing and applying a LUR model. It considers both conventional and novel potential predictor variables. GDAL/OGR libraries are used to do spatial analysis in the modeling and prediction. Developed on Python platform, PyLUR is rather efficient in data processing. Land use regression (LUR) models have been widely used in air pollution modeling. This regression-based approach estimates the ambient pollutant concentrations at un-sampled points of interest by considering the relationship between ambient concentrations and several predictor variables selected from the surrounding environment. Although conceptually quite simple, its successful implementation requires detailed knowledge of the area, expertise in GIS, statistics, and programming skills, which makes this modeling approach relatively inaccessible to novice users. In this contribution, we present a LUR modeling and pollution-mapping software named PyLUR. It uses GDAL/OGR libraries based on the Python platform and can build a LUR model and generate pollutant concentration maps efficiently. This self-developed software comprises four modules: a potential predictor variable generation module, a regression modeling module, a model validation module, and a prediction and mapping module. The performance of the newly developed PyLUR is compared to an existing LUR modeling software called RLUR (with similar functions implemented on R language platform) in terms of model accuracy, processing efficiency and software stability. The results show that PyLUR out-performs RLUR for modeling in the Bradford and Auckland case studies examined. Furthermore, PyLUR is much more efficient in data processing and it has a capability to handle detailed GIS input data.

关键词： LUR Air pollution modelling GIS spatial analysis GDAL/OGR Python Pollutant concentration mapping

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论GIS空间关系描述中存在的几个基本问题

邓敏,李成名,刘晓丽

《中国工程科学》 2013年第15卷第5期页码 20-24

摘要：

首先剖析了空间关系描述中“空间”的概念，论述了拓扑关系具有与实体位置本身无关的特性，进而阐述了空间实体的拓扑表达，分析了拓扑空间描述存在的不足，以及与地理环境、地理空间认知的相关性，提出了纳入度量特性的拓扑空间关系描述的方法。

关键词：空间拓扑空间关系空间关系描述

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Industrial eco-efficiency and its spatial-temporal differentiation in China

Wei YANG, Fengjun JIN, Chengjin WANG, Chen LV

《环境科学与工程前沿（英文）》 2012年第6卷第4期页码 559-568 doi: 10.1007/s11783-012-0400-4

摘要： The aim of this paper is to study the spatial-temporal differentiation of industrial eco-efficiency in China. Using methods based on the data envelopment analysis (DEA) model and exploratory spatial data analysis (ESDA) and data from 1985, 1995, 2005, and 2008 of 30 provinces in China, the spatial-temporal pattern changes in industrial eco-efficiency are discussed. The results show that: first, the patterns of industrial eco-efficiency are dominated by clustering of relatively low efficiency provinces; second, spatial relationships between the industrial eco-efficiencies of different provinces changed slightly throughout the period and the provinces persistently exhibit spatial concentration of relatively low industrial eco-efficiency; finally, there is an obvious trend in the polarization of industrial eco-efficiency, i.e., the higher level spatial units are concentrated in eastern China, and the lower level spatial units are mainly in western and central China.

关键词： industrial eco-efficiency data envelopment analysis (DEA) model exploratory spatial data analysis (ESDA)

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水电工程地质信息三维可视化与分析

刘东海,钟登华,李明超

《中国工程科学》 2004年第6卷第5期页码 65-70

摘要：

传统工程地质资料的描述和解释直观性差，往往不能充分揭示地质构造空间变化的规律，所以越来越难以满足设计人员进行空间地质分析的要求，文章利用GIS和可视化技术，提出了水电工程地质信息数字化与三维可视化方法

关键词：水电工程地质信息三维可视化 GIS 地质分析

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Fully integrated approach: an alternative solution of coupling a GIS and diffuse pollution models

S. LIU,R.E. BRAZIER,A. L. HEATHWAITE,W. LIU

《环境科学与工程前沿（英文）》 2014年第8卷第4期页码 616-623 doi: 10.1007/s11783-013-0589-x

摘要： As a tool for management, query, visualization and analysis of spatially referred information, GIS has been recognized as a method to aid the modeling of diffuse pollution and visualize the results in a spatial context. A common question in integrating diffuse pollution models and GIS is to choose a suitable coupling approach, in which the feature of diffuse pollution models should be taken into account. In this paper, we report on our experience in coupling a distributed diffuse pollution model with a GIS. A prototype of fully integrated system is developed in this paper. This system has high flexibility, extendibility and great data management efficiency. Differences in applicability of loose coupling, tight coupling and fully integrated approaches are addressed. It is concluded that the fully integrated approach can avoid tanglesome data exchange and routine execution and more robust than loose and tight coupling approaches and is suitable for distributed diffuse pollution modes.

关键词： diffuse pollution GIS modeling nutrients phosphorus

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Border-search and jump reduction method for size optimization of spatial truss structures

Babak DIZANGIAN, Mohammad Reza GHASEMI

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 123-134 doi: 10.1007/s11709-018-0478-2

摘要： This paper proposes a sensitivity-based border-search and jump reduction method for optimum design of spatial trusses. It is considered as a two-phase optimization approach, where at the first phase, the first local optimum is found by few analyses, after the whole searching space is limited employing an efficient random strategy, and the second phase involves finding a sequence of local optimum points using the variables sensitivity with respect to corresponding values of constraints violation. To reach the global solution at phase two, a sequence of two sensitivity-based operators of border-search operator and jump operator are introduced until convergence is occurred. Sensitivity analysis is performed using numerical finite difference method. To do structural analysis, a link between open source software of OpenSees and MATLAB was developed. Spatial truss problems were attempted for optimization in order to show the fastness and efficiency of proposed technique. Results were compared with those reported in the literature. It shows that the proposed method is competitive with the other optimization methods with a significant reduction in number of analyses carried.

关键词： optimum design sensitivity analysis reduction method spatial trusses OpenSees

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Regional GIS-based evaluation of the potential and supply costs of forest biomass in Sweden

Dimitris ATHANASSIADIS, Tomas NORDFJELL

《农业科学与工程前沿（英文）》 2017年第4卷第4期页码 493-501 doi: 10.15302/J-FASE-2017179

摘要： The potential for harvestable forest fuel (logging residues and stumps from regeneration fellings and small diameter trees from early thinnings) in Sweden, divided in five regions, is provided. Marginal cost curves for logging residues and stumps are calculated through a GIS-based method based on forest inventory plots and locations of selected terminals, and heat and combined heat and power facilities. Four supply chains for logging residues and two for stumpwood were compared. Fixed and variable costs of harvesting equipment and transport vehicles were used for determining the costs of each of the supply systems under consideration. A list with the GPS coordinates of all facilities and terminals was made based on their geographical location. The distance from the center of each forest inventory plot to the nearest receiving point within the region, either facility or terminal, was estimated. There were large differences in the estimated potential of harvestable forest fuel between the regions. The overall annual potential for each of the five regions ranged from 0.97 to 2.73 million oven dry tonnes and the total potential amounted to 9.39 Mt (oven dry). One of the northernmost regions (R1) had the steepest slope in its marginal cost curve. For the other regions, the slope of their cost curves was less dramatic. Information on the economic availability of logging residues and stumps in each region is important for forest fuel suppliers and receiving facilities.

关键词： GIS logging residues heat and-power faci-lities stumpwood

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Digital representation of meso-geomaterial spatial distribution and associated numerical analysis of

YUE Zhongqi

《结构与土木工程前沿（英文）》 2007年第1卷第1期页码 80-93 doi: 10.1007/s11709-007-0008-0

摘要： This paper presents the author's efforts in the past decade for the establishment of a practical approach of digital representation of the geomaterial distribution of different minerals, particulars, and components in the meso-scale range (0.1 to 500 mm). The primary goal of the approach is to provide a possible solution to solve the two intrinsic problems associated with the current main-stream methods for geomechanics. The problems are (1) the constitutive models and parameters of soils and rocks cannot be given accurately in geomechanical prediction; and (2) there are numerous constitutive models of soils and rocks in the literature. The problems are possibly caused by the homogenization or averaging method in analyzing laboratory test results for establishing the constitutive models and parameters. The averaging method employs an assumption that the test samples can be represented by a homogeneous medium. Such averaging method ignores the fact that the geomaterial samples are also consisted of a number of materials and components whose properties may have significant differences. In the proposed approach, digital image processing methods are used as measurement tools to construct a digital representation for the actual spatial distribution of the different materials and components in geomaterial samples. The digital data are further processed to automatically generate meshes or grids for numerical analysis. These meshes or grids can be easily incorporated into existing numerical software packages for further mechanical analysis and failure prediction of the geomaterials under external loading. The paper presents case studies to illustrate the proposed approach. Further discussions are also made on how to use the proposed approach to develop the geomechanics by taking into account the geomaterial behavior at micro-scale, meso-scale and macro-scale levels. A literature review of the related developments is given by examining the SCI papers in the database of Science Citation Index Expanded. The results of this review have shown that the proposed approach is one of the latest research and developments in geomechanics where actual spatial distribution and properties of materials and components at the meso-level are taken into account.

关键词： homogeneous numerical analysis Expanded homogenization meso-level

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基于GIS的地震火灾动态蔓延模拟

谢旭阳,任爱珠

《中国工程科学》 2007年第9卷第8期页码 82-87

摘要：

用惠更斯原理对震后火灾的动态蔓延过程进行了模拟，并开发了基于GIS的城市地震次生火灾动态蔓延模拟系统，该系统可以模拟单个或者多个起火点的动态蔓延过程

关键词：地震次生火灾 GIS 火灾动态蔓延模拟系统

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Oral product input to the GI tract: GIS an oral product performance technology

Gordon L. Amidon, Yasuhiro Tsume

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 516-520 doi: 10.1007/s11705-017-1658-7

摘要： The patient receives a pharmaceutical product, not a drug. The pharmaceutical products are formulated with a drug, an active ingredient to produce the maximum therapeutic effect after oral absorption. Therefore, it is the product we must optimize for the patients. In order to assure the safety and efficacy of pharmaceutical products, we need an predictive tool for oral product performance in patients. Currently, we are a surprisingly long way from accomplishing that objective. If the 20th century was the ‘age of the drug’, i.e., the ‘magic bullet’, the 21st century must become the ‘age of the guided missile’, i.e., the delivery system, including the form of the active pharmaceutical ingredient (API) (‘drug’). The physical form of the drug and the delivery system must be optimized to maximize the therapeutic benefits of pharmaceutical products for humans. Oral immediate release (IR) dosage forms cannot be optimal for all drugs or likely even any drugs (APIs). Still, the formulation of pharmaceutical products has to be optimized for patients. But how do we optimize oral delivery of drugs? It is usually through ‘trial and error’, in humans! We need a better way to optimize the oral dosage forms. We have suggested to select different dissolution methodologies for this optimization based on BCS Subclasses. In this article, we present the predicted drug dissolution profile of ketoconazole as a model drug from our laboratory utilizing a gastrointestinal simulator (GIS), which is an adaptation of the ASD system. GIS consists of three chambers representing stomach, duodenum, and jejunum, to create the human gastrointestinal tract-like environment and enable the control the gastric emptying rate. This dissolution system allows the monitoring of the drug dissolution phenomena and the observation of the supersaturation and the precipitation of pharmaceutical products, which is useful information to predict dissolution of pharmaceutical products. This system can provide the actual input needed to accurately predict the input into the systemic circulation required by many of the absorption prediction packages available today.

关键词： GIS in vivo predictive dissolution ketoconazole BCS subclassification supersaturation

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基于GIS的混凝土坝施工可视化仿真技术及其应用

李景茹,钟登华

《中国工程科学》 2005年第7卷第8期页码 70-74

摘要：

将可视化技术与仿真技术相结合，提出了基于GIS的混凝土坝施工可视化仿真技术，开发了相应的软件GVSS。GVSS是用于制定和优化混凝土坝施工进度计划的工具，提供了可视化和查询等功能。

关键词：可视化仿真地理信息系统（GIS）混凝土坝施工进度优化

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Analysis on shear capacity of prestressed concrete spatial connections

XUE Weichen, LIU Zhenyong, JIANG Dongsheng

《结构与土木工程前沿（英文）》 2008年第2卷第4期页码 309-317 doi: 10.1007/s11709-008-0052-4

摘要： Based on experimental results of prestressed concrete spatial connections, nonlinear finite element models were established to analyze the shear capacity of spatial connections and parametric studies were performed using ANSYS. It is found that the shear capacity of spatial connection is influenced by joint hoop, beam prestress, column compressive load, and direction of resultant shear force. The parametric studies also indicate that the shear capacity of spatial connection under biaxial cyclic loading is lower than that of corresponding connections under plane loading. A design formula for calculating the shear capacity of spatial connections is proposed based on the parametric studies and verified by the available test results.

关键词： available direction nonlinear capacity compressive

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A comprehensive analysis of a 3-P (Pa) S spatial parallel manipulator

Yuzhe LIU,Liping WANG,Jun WU,Jinsong WANG

《机械工程前沿（英文）》 2015年第10卷第1期页码 7-19 doi: 10.1007/s11465-015-0324-3

摘要：

In this paper, a novel 3-degree of freedom (3-DOF) spatial parallel kinematic machine (PKM) is analyzed. The manipulator owns three main motions (two rotations and one translation) and three concomitant motions (one rotation and two translations). At first, the structure of this spatial PKM is simplified according to the characteristic of each limb. Secondly, the kinematics model of this spatial PKM is set up. In addition, the relationship between the main motions and concomitant motions is studied. The workspaces respectively based on the outputs and inputs are derived and analyzed. Furthermore, the velocity model is put forward. Two indexes based on the velocity model are employed to investigate the performance of this spatial PKM. At last, the output error model can be obtained and simulated. The comprehensive kinematics analysis in this paper is greatly useful for the future applications of this spatial PKM.

关键词： parallel mechanism concomitant motions kinematics workspaces error model

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Beyond bag of latent topics: spatial pyramid matching for scene category recognition

Fu-xiang LU,Jun HUANG

《信息与电子工程前沿（英文）》 2015年第16卷第10期页码 817-828 doi: 10.1631/FITEE.1500070

摘要： We propose a heterogeneous, mid-level feature based method for recognizing natural scene categories. The proposed feature introduces spatial information among the latent topics by means of spatial pyramid, while the latent topics are obtained by using probabilistic latent semantic analysis (pLSA) based on the bag-of-words representation. The proposed feature always performs better than standard pLSA because the performance of pLSA is adversely affected in many cases due to the loss of spatial information. By combining various interest point detectors and local region descriptors used in the bag-of-words model, the proposed feature can make further improvement for diverse scene category recognition tasks. We also propose a two-stage framework for multi-class classification. In the first stage, for each of possible detector/descriptor pairs, adaptive boosting classifiers are employed to select the most discriminative topics and further compute posterior probabilities of an unknown image from those selected topics. The second stage uses the prod-max rule to combine information coming from multiple sources and assigns the unknown image to the scene category with the highest ‘final’ posterior probability. Experimental results on three benchmark scene datasets show that the proposed method exceeds most state-of-the-art methods.

关键词： Scene category recognition Probabilistic latent semantic analysis Bag-of-words Adaptive boosting

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Spatial impacts of climate factors on regional agricultural and forestry biomass resources in north-eastern

Wenyan Wang, Wei Ouyang, Fanghua Hao, Yun Luan, Bo Hu

《环境科学与工程前沿（英文）》 2016年第10卷第4期 doi: 10.1007/s11783-016-0864-8

摘要： Dynamic analysis of biomass combined NPP modeling has been adopted. Temperature trends to warming and precipitation has periodic fluctuation. Regional distribution of agricultural and forestry biomass is mutual and divergent. Precipitation is significantly positive correlated with agricultural biomass. Temperature is negative on forestry biomass in Lesser Khingan & northern Changbai. Precipitation plays positive effect on biomass in southwestern Changbai Mountain. The dynamics of agricultural and forestry biomass are highly sensitive to climate change, particularly in high latitude regions. Heilongjiang Province was selected as research area in North-east China. We explored the trend of regional climate warming and distribution feature of biomass resources, and then analyzed on the spatial relationship between climate factors and biomass resources. Net primary productivity (NPP) is one of the key indicators of vegetation productivity, and was simulated as base data to calculate the distribution of agricultural and forestry biomass. The results show that temperatures rose by up to 0.37°C/10a from 1961 to 2013. Spatially, the variation of agricultural biomass per unit area changed from -1.93 to 5.85 t·km ·a during 2000–2013. More than 85% of farmland areas showed a positive relationship between agricultural biomass and precipitation. The results suggest that precipitation exerts an overwhelming climate influence on agricultural biomass. The mean density of forestry biomass varied from 10 to 30 t·km . Temperature had a significant negative effect on forestry biomass in Lesser Khingan and northern Changbai Mountain, because increased temperature leads to decreased Rubisco activity and increased respiration in these areas. Precipitation had a significant positive relationship with forestry biomass in south-western Changbai Mountain, because this area had a warmer climate and stress from insufficient precipitation may induce xylem cavitation. Understanding the effects of climate factors on regional biomass resources is of great significance in improving environmental management and promoting sustainable development of further biomass resource use.

关键词： Biomass resources Net primary productivity (NPP) Climate change Heilongjiang Province China Climate Energy systems/technology Other sustainability (specify) Statistical methods GIS Model flow CFD