基于生命周期理论的煤矿区 土地利用演化模拟

准确、可靠地模拟和预测煤矿区土地利用结构的变化,是矿区制定土地利用规划、土地复垦措施的重要依据。考虑到元胞自动机模型(CA)在土地利用结构变化模拟和预测方面的优越性能,将CA模型引入了矿区土地利用结构变化的模拟和预测。但矿区在不同的发展阶段,土地利用类型之间的转换具有不同方式,使得土地利用结构的演化存在阶段性的特点。因而利用CA模型对矿区的土地利用变化进行模拟和预测,就要求在不同阶段使用不同的转换规则,而传统CA模型难以满足这样的要求。本文基于矿区生命周期理论,改进了传统CA模型,通过控制变量的引入,实现了元胞转换规则的动态获取和应用。为了验证模型的有效性,以潞安矿区为研究区域,常村矿为研究对象,利用改进的模型对常村矿的土地利用空间结构进行了成熟期和衰退期的预测。通过和传统CA模型预测结果的比较,表明该模型的预测结果和矿区的不同阶段的土地利用演化特点比较吻合。因此该模型能够提高矿区土地利用结构演变模拟和预测的精度,是有效可行的方法。     

Exploring the impacts of future tourism development on land use/cover changes

Land use/cover changes (LUCC) are central to tourism because land is used in multiple ways as a resource for tourism-focused activities. Tourism is essentially a geographical phenomenon, encompassing the movement and flow of people (seen as the demand side) and spatial distribution patterns relating to land use consumption (seen as the supply side). However, the impacts of tourism on LUCC are difficult to track and monitor. Contributing factors of this problem include a lack of empirical studies, shortage of micro-level LUCC datasets, and scarce methodological frameworks which can be used for assessments. This paper aims to provide a LUCC modelling approach in order to explore the impacts of tourism development on built-up areas. We developed a Cellular automata model (CA) which integrates Markovian transition probabilities and logistic regression transition suitability maps. LUCC rules for tourism development are framed within the national land use policy guidelines for the development of new tourism accommodation establishments (TAE). This primarily takes into consideration land cover compatibility and the proposed development's proximity to the coastline.Three scenarios were established to explore the impacts of tourism development in LUCC for the year 2020 in a Portuguese coastal region: business as usual (BAU); tourism trends (TOUR); and natural restrictions (NATR). TOUR results indicate that the tourism and urban land use/cover growth is higher and focuses heavily on the coastal region (within 5,000 m) when compared to the other scenarios. The overall results for BAU and NATR show a general convergence with the land use policy guidelines in terms of tourism nucleation and new TAE distance to the coastline.     

建筑物出口的人员疏散研究

根据建筑物出口疏散的特点,提出了一种改进型的元胞自动机模型。研究了影响人员疏散速度的两个因素:人员之间的相互拥挤产生的冲突和人员移动到出口时由于转弯导致的移动速度减慢。使用数学方法推导得出了摩擦冲突函数和转弯函数。通过计算机仿真与实际疏散实验对比发现,在不考虑转弯因素的情况下,仿真结果与实验结果偏差较大,而在同时考虑相互冲突和转弯因素时的仿真结果与实验结果偏差很小,验证了这两个因素是疏散仿真不可忽略的因素。通过分析仿真结果,验证了本文所采用的模型和函数能够准确地反映实际疏散过程,具有较高的实用价值。     

Foliar Applied Nickel on Buckwheat (Fagopyrum esculentum) Induced Phenolic Compounds as Potential Antioxidants

In this study, Fagopyrum esculentum (common buckwheat) sprayed with nickel (Ni) (0, 0.5, 1.0, 3.0, and 5.0 mM) for different duration has been investigated for Ni accumulation, malondialdehyde (MDA), total phenolics, and phenolic acids. Ni accumulation significantly increased in dose‐dependent manner. Plants exposed for 72 h, showed visible damages as chlorosis and irreversible necrosis. The MDA and total phenolic contents increased at 24 h of Ni treatments. HPLC data revealed that phenolic acids are in good correlation with concentration and durations of treatments. After 24 and 48 h the contents of chlorogenic, p‐hydroxybenzoic, hesperetic, p‐anisic, and caffeic acids increased in Ni treated leaves. On the other hand, p‐hydroxybenzoic, hesperetic, p‐anisic, p‐coumaric, caffeic acids contents decreased after 72 h of Ni exposure. Vanillic and cinnamic acid followed same pattern and increased significantly at 3.0 and 5.0 mM after 48 h of Ni exposure. It may suggest that buckwheat can be possible hyperaccumulators of Ni, because of high Ni accumulation in tissues through foliar treatment. Furthermore, the analyzed phenolic acids have potential role as antioxidants, which provide tolerance to buckwheat against Ni treatment.     

基于应变率场的全球地震活动特征模拟探索

提出利用全球应变率资料模拟全球地震活动特征的基本思想,并作了初步探索。利用GSRM的全球应变率场结果,初步设计了模拟全球地震活动时空分布特征的细胞自动机模型。该模型把地球考虑为一个自组织的整体系统,制定了细胞自动机的演化规则,获得了模拟的人工地震目录。初步的模拟结果基本反映了全球地震活动的主要分布特征,体现了全球构造活动强弱的主要格局,初步达到了利用GPS等实测资料计算的应变率作为细胞自动机网格状态及其改变量来模拟复杂的全球地震活动特征的实验目的。     

用于检测同相轴的Duffing型系统恢复力项的讨论

在用于检测同相轴的Duffing型系统中，非线性恢复力项的选取至关重要．针对具有不同非线性恢复力项的混沌系统，本文首先就非线性恢复力项的来源进行了说明，然后通过对哈密顿系统和耗散系统的仿真实验分析，以及理论推导，确定了势能—哈密顿多项式方程中可用于混沌振子检测系统的各项幂次和各项系数组合关系，即非线性恢复力项的选取规则：幂次最高项为奇次，其系数大于零．     

地震强度分布不均匀性的摩擦时间依从CA模型

设计一个摩擦时间依从的地震活动性细胞自动机模型（CA），研究产生地震累积频度-震级关系曲线中，出现拐点的地震强度分布不均匀现象的物理原因。外界通过应力加载向模型输入能量，模型的细胞之间存在非线性的相互作用。对比分析规定单个细胞破裂与模型地震之间不同的决定规则时产生的地震序列的累积频度-震级关系，研究结果表明，地震的级联破裂方式是引起累积频度-震级关系在震级较低范围和震级较高范围之间不连续的因素之一。     

模拟固体中波动过程的细胞自动机建模研究

In this paper, based on the principle of the statistical physics, cellular automatamodelling for wave propagation problem is studied and a cellular automata model forP wave in compex media is proposed. In order to examine the correctness of themodel, a comparision between the results of the cellular automata approach andfinite-difference method for same synthetic model is made. The comparision showsthe cellular automata model given here is feasible.     

Ecological footprint analysis based on RS and GIS in arid land

Sustainable development has become a primary objective for many countries and regions throughout the world now. The ecological footprint (EF) is a kind of concise method of quantifiably measuring the natural capital consumption and it can reflect the goal of sustainability. In this paper, the concept, the theory and method of ecological footprint are introduced. On this basis, the study brings forward the method of ecological footprint and capacity prediction. The method is employed for the ecological footprint prediction combining consumption model with population model and the technique is adopted for the ecological capacity (EC) prediction uniting the Geographical Cellular Automata (Geo CA) and Geographic Information System (GIS). The above models and methods are employed to calculate EF and EC in 1995 and 2000 and predict them in 2005 in Hexi Corridor. The result shows that EF is continually increasing, and EC ascended in the anterior 5 years and will descend in the posterior 5 years. This suit of method is of the character of accuracy and speediness.