关于地缘研究的理论探讨

地缘政治学经历湮灭、复苏之后,自70年代以来在西方获得了广泛的发展。而在我国它却长期受到多方面的束缚,其中包括认识上的混乱。作者在文章中首先从地缘政治学的历史及其汉语翻译的角度,以及从地缘政治与地理的关系,澄清了“地缘”的概念。接着阐述了其研究内容,诸如地缘政治、地缘经济、地缘文化、地缘战略等。最后,对“地缘优势”一词的概念和内函作了进一步的探讨,并指出把“地缘优势”与通常的地理优势区别开来,具有重要的现实意义。     

Impacts of Non-farm Employment of Rural Laborers on Agricultural Land Use: Theoretical Analysis and Its Policy Implications

During rapid urbanization and industrialization process, non-farm employment of rural laborers has emerged as a prevalent phenomenon in rural areas of China and become an important driving factor for changes in agricultural land use. This article attempts to theoretically analyze the impacts of non-farm employment of rural laborers on agricultural land use based on economic frameworks. As rational agents, farmers aim to maximize their income and follow equilibrium principles when they decide how to allocate their labor forces (or working time) in two departments (farm and non-farm) and how to use their agricultural land with different quality and location. The income earned by non-farm employment is higher, and there exists a comparative advantage between labors, as a result the quantity and quality of labor input in agricultural land use decreases. With the limitation of labor input during agricultural land use decision-making of farm households, on the one hand, land with higher quality is still utilized by farmers. On the other hand, poor quality land will be less well managed and is more likely to be abandoned. Non-farm employment of rural laborers and the rising of opportunity costs will result in abandonment of poor quality land, and great importance should be attached to this by policy makers.     

晋城无烟煤储存游离态CO2理论容量及其影响因素

深部煤层游离态CO₂理论存储容量随深度增加而变化。基于山西沁水盆地南部煤样测试基本数据,对游离态CO₂煤层存储容量进行计算,并分析其随深度变化规律。基于建立的煤层游离态CO₂存储容量计算模型显示,煤储层游离态CO₂存储容量受孔隙度、含气饱和度、地层温度、地层压力等共同作用的影响。CO₂注入后改变煤储层物性会导致理论存储量有不同程度增加,但存储量增值与实验煤样颗粒大小有关;应力作用下煤储层孔隙度随埋深呈负指数降低规律会显著降低CO₂存储容量,含气饱和度增大会显著增大存储量。     

地震资料预测压力方法和展望

综合介绍和评价了地震资料预测压力的各种方法,认为目前提高地震资料预测压力精度的根本方法是提高速度分析的精度和获得有针对目标区块的经验公式;同时详细分析了获取压力预测速度时需要注意的问题和可能的陷阱;提出利用声波时差等测井资料和实测压力资料获得单井压力模型,并应用单井压力模型指导速度拾取的速度分析方法,该方法基本排除各种非压力因素造成的速度异常.     

地理学理论研究和科学分析的一般方法探讨

根据近年来地理学家和物理学家对城市发展和演化分析的有关成果,总结出地理理论研究方法的一般模式:第一步,根据观测数据建立经验模型;第二步,构造假设、建立理论方程并且求解,求解的结果要与经验模型及其参数一致;第三步,基于第二步的假设条件进行计算机模拟实验,模拟结果要与观测的结果一致。第一步用到的方法从地理学"计量运动"时期开始发展,至今已经比较成熟;第二步用到的方法发展多年,但进展较慢;第三步用到的方法目前正在快速发展,但没有与第二步的方法有机结合。强调的方法在于,将地理学的经验建模、理论解析和模拟实验有机结合起来,形成一个完整的、不同步骤相辅相成的研究程序。这一套方法在一定条件下可以推广到地理应用研究领域,推广之后的第二步可以大为简化,但第三步则会更加复杂。     

海南环岛理论最低潮面形态曲线模型研究

在分析了海南海洋测量深度基准建立现状基础上,提出在海南建立环岛理论最低潮面形态曲线模型的概念,并分析了建立该模型的具体方法,对解决海洋测量深度基准问题具有一定的指导意义.     

Exploitable wave energy assessment based on ERA-Interim reanalysis data—A case study in the East China Sea and the South China Sea

Wave energy resources assessment is a very important process before the exploitation and utilization of the wave energy. At present, the existing wave energy assessment is focused on theoretical wave energy conditions for interesting areas. While the evaluation for exploitable wave energy conditions is scarcely ever performed.Generally speaking, the wave energy are non-exploitable under a high sea state and a lower sea state which must be ignored when assessing wave energy. Aiming at this situation, a case study of the East China Sea and the South China Sea is performed. First, a division basis between the theoretical wave energy and the exploitable wave energy is studied. Next, based on recent 20 a ERA-Interim wave field data, some indexes including the spatial and temporal distribution of wave power density, a wave energy exploitable ratio, a wave energy level, a wave energy stability, a total wave energy density, the seasonal variation of the total wave energy and a high sea condition frequency are calculated. And then the theoretical wave energy and the exploitable wave energy are compared each other; the distributions of the exploitable wave energy are assessed and a regional division for exploitable wave energy resources is carried out; the influence of the high sea state is evaluated. The results show that considering collapsing force of the high sea state and the utilization efficiency for wave energy, it is determined that the energy by wave with a significant wave height being not less 1 m or not greater than 4 m is the exploitable wave energy. Compared with the theoretical wave energy, the average wave power density, energy level, total wave energy density and total wave energy of the exploitable wave energy decrease obviously and the stability enhances somewhat. Pronounced differences between the theoretical wave energy and the exploitable wave energy are present. In the East China Sea and the South China Sea, the areas of an abundant and stable exploitable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait,east of Taiwan, China and north of Ryukyu Islands; annual average exploitable wave power density values in these areas are approximately 10–15 k W/m; the exploitable coefficient of variation(COV) and seasonal variation(SV)values in these areas are less than 1.2 and 1, respectively. Some coastal areas of the Beibu Gulf, the Changjiang Estuary, the Hangzhou Bay and the Zhujiang Estuary are the poor areas of the wave energy. The areas of the high wave energy exploitable ratio is primarily in nearshore waters. The influence of the high sea state for the wave energy in nearshore waters is less than that in offshore waters. In the areas of the abundant wave energy, the influence of the high sea state for the wave energy is prominent and the utilization of wave energy is relatively difficult. The developed evaluation method may give some references for an exploitable wave energy assessment and is valuable for practical applications.     

福建省永泰县东门旗山滑坡诱发机理与防治措施

为明确降雨诱发滑坡机理及为防治措施确定依据,本文以福建省永泰县东门旗山滑坡为研究案例,在充分的地质勘探资料以及降雨期间滑坡位移监测数据的基础上,从内部与外部因素两个方面分析了滑坡的诱发机理,并通过数值方法对滑坡稳定性演化历程进行了反分析,将滑坡治理分为应急处理与长期加固两个阶段。在应急处理阶段,以拦排地表与地下水为主要工程措施,依据滑坡体不同部位滑动速率与降雨量的关系,验证推移式滑坡判断,得出先将排水措施布设于滑坡下部的结论;在长期加固方面,以抗滑桩为主要加固措施,以抗滑桩工程造价最低为优化目标,结合数值模拟与理论计算方法,得到最优抗滑桩设计方案为布桩于滑坡体中下部、桩径1.0 m、桩净距与中心距分别为2.0 m和3.0 m。     

西北干旱区不稳定耕地概念与分类研究——以新疆昌吉州为例

厘清西北干旱区不稳定耕地的资源清单对于维持区域生态平衡至关重要.当前,全国对不稳定耕地的定义和分类比较笼统,难以突出西北干旱区不稳定耕地的特征.本文阐明了西北干旱区不稳定耕地的概念,并根据不稳定因素构建了分类体系.同时以昌吉州为例,分析不稳定耕地的数量、质量与空间分布.结果表明:①昌吉州不稳定耕地面积为14.56万hm...     

植物消波机制的实验与理论解析研究进展

从以物理模型实验及理论解析为代表的植物消波研究手段与宏观和微观尺度下植物消波分析方法两个方面总结了国内外的研究现状和最新研究进展。对物理模型实验中的植物因子、水动力因子、植物模型制作和实验布置等要素以及理论解析模型进行归纳,分别阐述了以波高衰减和波能耗散为主要分析对象的植物消波分析方法,指出现有物理模型实验中植物几何比尺与波要素比尺难以统一和理论解析研究局限于二维情况等问题。综合考虑季节更替、植物摆动、波浪破碎、波浪随机性及非线性、潮流等因素是今后植物消波研究的重点突破方向。