USERS′ PERCEPTION OF KOWLOON PARK, HONG KONG： VISITING PATTERNS AND SCENIC ASPECTS

Hong Kong is a hyper-dense city with 7×10⁶ people living in an area of 1100km². One way to improve the livability of compacted and congested cities like Hong Kong is through the provision of urban parks, an aspect that has largely been under-researched. This study focuses on how users perceive and utilize various facilities in the Kowloon Park. The findings revealed that the Kowloon Park is one of the most preferred parks in Hong Kong for both local residents and tourists. Users were quite satisfied with the park’s facilities. Notably, the most important component of an urban park is its greenery. This is followed by water elements, seating places, and facilities for various recreational activities. The improvements users would like to see in urban parks include good design and management, meeting users’ needs, overcoming barriers to use, and providing a high quality and varied experience for different groups in the community. The findings of this study provide a good basis to address park management issues from the users’ perspective. In particular, parks should provide easy access, encourage optimum usage and enable complimentary improvements to the environment. Foundation item: Under the auspices of the Germany-Hong Kong Joint Research Scheme (No.GER/99-00/01) and the Faculty Research Grant of the Hong Kong Baptist University (No.FRG/00-01/I-38) Biography: WONG Koon-kwai (1950—), male, a native of Guangdong Province, Ph.D., associate professor, specialized in the analysis of human-environment interaction. E-mail: kenwong@hkbu.edu.hk     

一种地温传感器及其在大地震临震前兆监测中的应用

介绍了地球内部温度异常与地震孕育和发生的关系以及地温异常在地震预测中的应用,分析了现有的地温测量传感技术,提出了一种用于大地震临震前兆监测的深层地温传感器,描述了基于该传感器进行大地震临震前兆监测的方法和系统架构,使得结合其他手段进行地震三要素预测成为可能。     

Mapping soil effects in Barcelona, Spain, through an integrated GIS environment

Maps of soil response for the city of Barcelona have been for the first time obtained through a GIS environment that integrates the different procedures for soil response estimation within a single tool. These maps constitute part of the results of the local scale application of the computer prototype for seismic risk assessment that was developed within the European project SERGISAI. The approach involves: collection of available data relevant to local geology, implementation of geotechnical models, estimation of the reference seismic action, generation of synthetic strong-motion time histories, and soil response calculation through 1D analytical method. The resulting predictive hazard maps of predominant period and amplification ratio delineate potential variations on ground shaking and constitute a first approximation towards an integrated approach to Barcelona urban area microzonation. Analysis of the observed differences, when comparing the analytical results in this study with previous empirical studies, provides a useful feedback to establish site dependence suitability and reliability of methods, to extract information on at-present inaccessible parameters needed for the characterisation of physical properties of soil, and also to delimit those areas where further in-depth survey research is needed for a proper seismic hazard assessment.     

模拟地震的弹簧滑块模型的混沌运动

我们构造了一种自由度为２的双弹簧滑块系统，讨论模型参数的不均匀性和滑块间的相互作用与复杂现象的关系。假定滑块在所受力小于其静摩擦力时保持静止，因此，只有发生了滑动，两滑块所受力之差才改变。如果我们以两滑块受力之差为变量，就可以构造一种一维的映射。这种映射直观地显示了系统的演化，反映了方程终态解的形态。结果表明，用混沌运动来描述地震现象可能是较为合理的。     

云南地区6级以上地震前M_s≥4.7级地震的时空特征标度

本文研究了1920年以来,云南地区M_s≥4.7级地震的时间序列及空间分布的特征标度。结果表明,当区内M_s≥4.7级地震在时间序列上出现我们定义的平静段和活跃段后,分别于418天和312天内即可能发生6级以上地震,对应率分别为71％和87％,1920年以来云南11次M_s≥6.8级地震前,出现活跃和平静特征标度的各5次。在空间上绝大多数(80％)大震震中处于我们所定义的长时间大范围空白缺震背景区或相对少震区内,仅少数(20％)位于4.7级以上地震相对密集区内或附近。4.7级以上地震上述时间序列及空间分布特征标度,可以作为云南6级,特别是6.8级以上地震中期或短期预测的判据和指标。同时可以看出,云南6级以上地震前,4.7级以上地震在时空演变上,经历了从无序到有序的演化过程。     

Location Accuracy of the China National Seismograph Network Estimated by Repeating Events

INTRODUCTIONDigital seismological observation in China has had a significant development in recent years,especiallysince the last five years(Liu Ruifeng,et al.,2003).For further development,it isnecessarytoassessthe monitoringcapabilityof the existingseismological network.One of theimportantassessments is the estimation of regionalizedlocation accuracy.Upto present,several approaches have been proposed to assess the location accuracy,such asthe groundtruth event approach(e.g.,Lienert,199…     

关于在地震预报中遇到的几个问题的探讨

地震台站工作人员 ,在进行观测资料分析、地震预报研究过程中 ,往往会遇到的几个问题 :1、手段单一 ,对于前兆现象无法全面表述。 2、如何识别异常与地震之间的关系。 3、如何兼顾点和面的关系。     

Outgoing long wave radiation variability from IR satellite data prior to major earthquakes

Our analysis of the continuous outgoing long wave earth radiation (OLR) indicates anomalous variations prior to a number of medium to large earthquakes. The most recent analysis of OLR is from the M9.0 Sumatra Andaman Islands mega trust event. We compared the reference fields for December 2001 to 2004 and found OLR anomalous values, > 80 W/m², (2σ) within the epicentral area on Dec 21, 2004, 5 days before the event. We used the NOAA/IR daily (one degree) and monthly (two and half degree) gridded data to differentiate between the global and seasonal variability and the transient local anomalies. The cause of such anomalies is not fully understood; one possible explanation is the existence of thermal outgoing radiation as a result of near ground air ionization and latent heat change due to change of air humidity and temperature. This phenomenon is hypothesized to be part of a relationship between tectonic stresses, electrochemical and thermodynamic processes in the atmosphere and increasing mid IR flux, all part of a family of electromagnetic (EM) phenomena related to earthquake activity. The time scale of the observed variations is a few weeks before the onset of the seismic event. In comparison with several years of data, the observed time-series preceding the earthquake had unusually high OLR. The OLR anomaly corresponds to a large area of ground coverage and coincides with the main epicentral zone. The significance of these observations is explored using data from most recent East Asian earthquake swarm of December 2004 and three other earthquakes.     

Vp/Vs Anisotropy and Implications for Crustal Composition Identification and Earthquake Prediction

Abstract: The ratio of P- to S-wave velocities (Vp/Vs) is regarded as one of the most diagnostic properties of natural rocks. It has been used as a discriminant of composition for the continental crust and provides valuable constraints on its formation and evolution processes. Furthermore, the spatial and temporal changes in Vp/Vs before and after earthquakes are probably the most promising avenue to understanding the source mechanics and possibly predicting earthquakes. Here we calibrate the variations in Vp/Vs in dry, anisotropic crustal rocks and provide a set of basic information for the interpretation of future seismic data from the Wenchuan earthquake Fault zone Scientific Drilling (WFSD) project and other surveys. Vp/Vs is a constant (Ф0) for an isotropic rock. However, most of crustal rocks are anisotropic due to lattice-preferred orientations of anisotropic minerals (e.g., mica, amphibole, plagioclase and pyroxene) and cracks as well as thin compositional layering. The Vp/Vs ratio of an anisotropic rock measured along a selected pair of propagation-vibration directions is an apparent value (Фij) that is significantly different from the value for its isotropic counterpart (Ф0). The usefulness of apparent Vp/Vs ratios as a diagnostic of crustal composition depends largely on rock seismic anisotropy. A 5% of P- and S-wave velocity anisotropy is sufficient to make it impossible to determine the crustal composition using the conventional criteria (Vp/Vs≤1.756 for felsic rocks, 1.7561.944 fluid-filled porous/fractured or partially molten rocks) if the information about the wave propagation-polarization directions with respect to the tectonic framework is unknown. However, the variations in Vp/Vs measured from borehole seismic experiments can be readily interpreted according to the orientations of the ray path and the polarization of the shear waves with respect to the present-day principal stress directions (i.e., the orientation of cracks) and the frozen fabric (i.e., foliation and lineation).     

The spatial and temporal changes inV p /V s before strong earthquakes in Kamchatka

A method was developed to obtain from a signal station the spatial and temporal distribution ofV _p /V _s ratios before earthquakes of magnitude>6. It was shown thatV _p /V _s values strongly depend upon the relative positions of the stations, the future large earthquake and the foci of the smaller earthquakes used forV _p /V _s determination. The appearance of a zone of anomalousV _p /V _s values with linear dimensions of the order of 100 km was noted at least 4 years before a deep earthquake of magnitude 7. Similar size anomalous zones were detected one year before some magnitude 6 earthquakes. V _p /V _s values decreased by a small but distinct amount during this time. Additionally, local short term minima inV _p /V _s ratios were observed some months before the major event. The epicenters of the large earthquakes were located within the 100 km size zone where the gradients of theV _p /V _s field were largest.