海浪局部频率及波面水质点局部速度的统计分布

根据平稳正态随机过程和Ｈｉｌｂｅｒｔ变换的性质,推导了海浪局部频率及波面水质点局部速度的统计分布,以Ｐｉｅｒｓｏｎ－Ｍｏｓｃｏｗｉｔｚ谱为例进行了讨论。本文的结果为解释与海上结构物ｒｉｎｇｉｎｇ现象产生有关的海浪事件提供了一种可能的参考依据。     

影像局部直方图匹配滤波技术用于遥感影像数据融合

本文提出了一种基于局部直方图匹配波技术的影像融合新方法。该方法分析了局部影像统计特性,应用均值或均值－方差匹配正态函数,对要融合的两幅影像局部直方图进行匹配。文中给出了３种不同的融合算法（高通滤波法,局部均值匹配法和局部均值与方差匹配法）用于ＳＰＯＴ全色影像和ＴＭ多光谱影像融合的结果,并进行了比较,质量评价结果证明了提出的方法在提高了原ＴＭ多光谱影像空间分辨率的同时,较好地保留了多光谱影像频道的光     

Local Uniqueness in the Global Village: Heritage Tourism in Singapore

It is commonly assumed that the development of tourist attractions, the formulation of tourism policies, and the marketing of destination areas are dictated by the needs and interests of foreign visitors. What is ignored is the role that local factors and agencies play in these processes. This paper explores the way local and non-local factors are responsible for shaping the form and function of tourism development. Drawing upon the case of Singapore, I examine the country's heritage tourism phenomenon as the outcome of “local” and “global” forces. This argument is elaborated along three lines of enquiry. They include: (a) a study of the government's tourism policies; (b) an examination of marketing and promotional strategies; and (c) a look at a particular urban landscape—the Little India Historic District. To conceptualize the global-local nexus, the paper embraces two bodies of theory. They are the “locality concept” advanced by industrial geographers in the 1980s, and writings on “globalism/localism” by cultural/economic geographers in the 1990s. Both theoretical discussions reinforce the argument that place uniqueness need not be sacrificed as a result of globalization. They also provide a way of viewing tourism geographies as the product of global and local forces.     

Culture Wars and NationalEducation Standards: Scale and the Struggle over Social Reproduction

America is embroiled in a culture war. National education standards have exacerbated the conflict. Supporters justify standards by adopting the rhetoric of globalization and national labor force preparedness. Opponents claim that standards threaten local control over value inculcation and social reproduction. This paper examines the “politics of scale” to hypothesize that conservatives have solicited Congressional support for local school choice and school prayer to subvert national education standards. Results from a multivariate analysis confirm that a significant link exists between Congressional opposition to education standards and support for school prayer and school choice.     

秦岭特长隧道涌水量的预测研究

论述了模糊聚类理论用于隧道涌水量预测的基本思路与方法, 提出了影响隧道涌水量的主要因素及其量化公式, 并以秦岭特长隧道 (Ⅱ线)为对象, 预测出其涌水量介于 1.0~ 3.0m3/d·m之间, 与该隧道开挖后的实际涌水量 2.07m3/d·m基本吻合, 从而证明了用该方法进行预测的合理性。      

Stiffened steel box columns. Part 1: Cyclic behaviour

This paper aims to study the cyclic inelastic behaviour of stiffened steel box columns failed by local and overall interaction instability under a constant compressive axial force and cyclic lateral loading. Such columns find broad application in steel bridge piers. The columns are of box sections with longitudinal stiffeners. In the analysis, a modified two‐surface plasticity model developed at Nagoya University is employed to model material non‐linearity. For comparison, analyses using classical isotropic‐ and kinematic‐hardening models are also carried out. Hysteretic curves and buckling modes obtained from analysis using the two‐surface model and classical models are compared with experimental results. Moreover, the progression of deformation from occurrence of local buckling to structural failure is discussed in detail. The comparisons show that the use of an accurate plasticity model is quite important in the prediction of both the cyclic inelastic behaviour and failure characteristic of steel box columns failed by coupled local and overall instability. It is found that the modified two‐surface model is a satisfactory model in predicting the cyclic hysteretic behaviour of both the thin‐ and thick‐walled steel box columns. Copyright © 2000 John Wiley & Sons, Ltd.     

Calibration of local magnitude scale for Hindukush continental subduction zone

Hindukush is an active subduction zone where at least one earthquake occurs on daily basis. For seismic hazard studies, it is important to develop a local magnitude scale using the data of local seismic network. We have computed local magnitude scale for Hindukush earthquakes using data from local network belonging to Center for Earthquake Studies (CES) for a period of three years, i.e. 2015–2017. A total of 26,365 seismic records pertaining to 2,683 earthquakes with magnitude 2.0 and greater, was used with hypocentral distance less than 600 km. Magnitude scale developed by using this data comes to be M_L = logA + 0.929logr + 0.00298r – 1.84. The magnitude determined through formulated relation was compared with that of standard relation for Southern California and relation developed by the same authors for local network for Northern Punjab. It was observed that Hindukush region has high attenuation as compared to that of Southern California and Northern Punjab which implies that Hindukush is tectonically more disturbed as compared to the said regions, hence, seismically more active as well. We have calculated station correction factors for our network. Station correction factors do not show any pattern which probably owes to the geological and tectonic complexity of this structure. Standard deviation and variance of magnitude residuals for CES network determined using Hutton and Boore scale and scale developed in this study were compared, it showed that a variance reduction of 44.1% was achieved. Average of magnitude residuals for different distance ranges was almost zero which showed that our magnitude scale was stable for all distances up to 600 km. Newly developed magnitude scale will help in homogenization of earthquake catalog. It has been observed that b-value of CES catalog decreases when magnitude is calculated by using newly developed magnitude scale.     

基于迭代局部搜索的区划问题算法研究

区划问题是将特定地理区域划分为若干空间连续的分区,满足分区内差异最小和分区间差异最大这一基本原则,广泛应用于地理、环境、生态、经济、农业、城市等领域。1960s以来,学者尝试建立各种区划问题数学模型,设计了一系列的求解算法,代表性的算法主要有：AZP、ARISEL、SKATER和REDCAP。本文提出了一个基于迭代局部搜索(ILS)的区划问题算法,进一步提升算法性能。该算法主要机制包括：邻域单元移动搜索改进分区质量;参照中心单元快速计算分区方差,提升算法速度;使用扰动机制跳出当前解局部最优状态;更新分区中心点提升分区方案目标值;使用群搜索探索更大的解空间;以及算法各步骤中通过分区空间连续判断和破碎修复保持分区空间连续。55个基准案例测试表明：ILS算法求解质量优于ARISEL和SKATER算法。一个多指标气候分区实验也表明：ILS算法求解质量优于SKATER、REDCAP和ARISEL算法。     

张其昀先生的区域地理学思想与成就

张其昀是中国近代科学地理学的创建者之一,为中国近代的地理学教育、人文地理学、政治地理学、历史地理学、区域地理学等的发展做出了卓越贡献.在区域地理学方面,他较早地将西方近代区域地理学作品介绍到国内,将"Regional Geography"翻译为"方志学",引入并阐释了西方区域地理学的概念、研究内容、研究方法等,并积极地...     

无线局域网在地震应急现场中的应用

地震应急是我国防震减灾工作3大体系之一,鉴于地震预报尚不过关,在没有作出临震预报而地震突然发生时,为在灾区进行有效的救援而采取的紧急行动.通信、计算机等新技术是地震应急指挥和救援工作顺利进行的重要保证,无线局域网是计算机网络与无线通信技术相结合的产物,无线局域网利用了无线多址信道的一种有效方法来支持计算机之间的通信,本文根据新疆地震局地震应急现场工作情况,阐述无线局域网在地震应急现场中的应用,讨论了地震应急现场所适应的几种无线局域网的组网模式.