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1.
基于TOPSIS评价法的城市应急避难所选址适宜性评价研究 总被引：1，自引：0，他引：1
由于城市中人口高度聚集,一旦发生灾害需疏散受灾居民到应急避难所中,因此应急避难所选址的合理性与适宜性就成为研究的重点。本文从经济性、效率性、公平性、安全性、可达性及环境因素等6个方面出发,选取12个应急避难所选址适宜性评价因子,并构建评价指标体系;利用TOPSIS评价方法构建适宜性评价模型,对研究区42处备选应急避难所的适宜性进行评价,结果表明:优秀级别8个、良好级别10个、中等级别23个、差等级别1个。研究结果可为应急管理部门在选择应急避难所建设位置时提供决策依据。 相似文献
2.
This paper reports the main results of the EC-ProjectSERGISAI. The project developed a computer prototypewhere a methodology for seismic risk assessment hasbeen implemented. Standard procedural codes,Geographic Information Systems and ArtificialIntelligence Techniques compose the prototype, whichpermits a seismic risk assessment to be carried outthrough the necessary steps. Risk is expressed interms of expected damage, given by the combination ofhazard and vulnerability. Two parallel paths have beenfollowed with respect to the hazard factor: theprobabilistic and the deterministic approach. Thefirst provides the hazard analysis based on historicaldata, propagation models, and known seismic sources.The deterministic approach provides the input forscenarios, by selecting a specific ground motion.With respect to the vulnerability factor, severalsystems have been taken into account apart frombuildings, which are usually considered in this typeof analysis. Defining vulnerability as a measure ofhow prone a system is to be damaged in the event of anearthquake, an attempt has been made to move from theassessment of individual objects to the evaluation ofthe performance of urban and regional areas. Anotherstep towards an approach which can better serve civilprotection and land use planning agencies has beenmade by adapting the analysis to the followinggeographical levels: local, sub-regional and regional.Both the hazard and the vulnerability factors havebeen treated in the most suitable way for each one, interms of level of detail, kind of parameters and unitsof measure. In this paper are shown some resultsobtained in two test areas: Toscana in Italy, for theregional level, the Garfagnana sub-area in Toscana,for the sub-regional level, and a part of the city ofBarcelona, Spain, for the local level. 相似文献
3.
Budd—Chiari综合征的CT评价 总被引：2，自引：0，他引：2
回顾性分析了５２例Ｂｕｄｄ－Ｃｈｉａｒｉ综合征的ＣＴ表现，ＣＴ显示肝尾叶增大５０例（９６％），肝脏呈低度密度或密度不均，４２例（８１％）肝静脉未明显，２２例（４２％）见有肝内侧枝血管，４９例（９４％）有肝外侧枝血管，作者认为ＣＴ检查对Ｂｕｄｄ－Ｃｈｉａｒｉ综合征有较高的诊断价值。 相似文献
4.
Gaetano Manfredi 《地震工程与结构动力学》2001,30(4):485-499
In this paper, a method is proposed in order to obtain a simplified representation of hysteretic and input energy spectra. The method is based on the evaluation of the equivalent number of cycles correlated to the earthquake characteristics by the proposed seismic index ID. This procedure allows us to obtain peak values of the hysteretic and input energy that depend on the demanded ductility, on the seismic index ID and on the peak pseudo‐velocity. The assessment of the input energy represents a first step towards the definition of a damage potential index capable of taking into account the effect of the duration of the ground motions. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
5.
Zhongliang Wu 《地震科学（英文版）》2022,35(4):293-296
Evaluation of numerical earthquake forecasting models needs to consider two issues of equal importance: the application scenario of the simulation, and the complexity of the model. Criterion of the evaluation-based model selection faces some interesting problems in need of discussion. 相似文献
6.
Evaluation of lake restoration in Sweden 总被引：1，自引：0，他引：1
Curt Forsberg 《Aquatic Sciences - Research Across Boundaries》1987,49(2):260-274
A large portion of the water resources in Sweden have been afflicted by acidification and eutrophication. Governmental grants
have been allocated for external and internal restoration measures for nutrient reductions, and are at the moment given for
liming operations in acidified lakes. Objective and results of the Swedish lake restoration programme during the last 20 years
are discussed and evaluated.
Presented at the International Conference on Lake Restoration in Zürich, 3–4 November 1986 相似文献
7.
We present a numerical evaluation of the potential improvements in seismic disturbance rejection to be obtained by using active variable damping control in a structure. Using the responses to seismic excitation of an optimally controlled variable structure and of a minimax-optimal designed fixed structure, we obtain an upper bound on the achievable performance and a lower bound on the acceptable performance of a control system for a variable-damping structure. Both of these bounds are relative to an energy-function criterion. Our numerical experiments lead to the following conclusions:
- (i) The gap between the upper and lower bounds is rather small, which makes designing a feedback law, that results in performance superior to that of a minimax-optimal designed structure, very difficult. The best choice for a feedback law appears to be continuous moving horizon control, whose implementation requires ground motion prediction up to 0.2 sec ahead, possibly using sensors located a small distance away from the site.
- (ii) A minimax-optimal designed structure gives very good seismic disturbance suppression, not only for the earthquakes used in its design, but also for other earthquakes of similar intensity. Controlled variable structures are likely to offer advantages when earthquakes are moderate to severe, particularly at sites, such as landfills and dry lake beds, where resonances can be expected, but the resonance frequency cannot be estimated in advance.
8.
Choon-Hooi Teoh 《Advances in water resources》1982,5(4):208-216
Relatively rapid and reliable procedures are required to determine reservoir storage-yield relationships during preliminary studies or reconnaissance surveys associated with regional assessments of surface water resources. Several techniques are available, but all are limited in their application. The following eight procedures were evaluated: Hurst (empirical), Alexander (gamma), Gould (synthetic), Dincer, Gould (gamma), Hardison (carryover), Guglij and McMahon (empirical). Each procedure was evaluated by application to 33 Australian and 12 Malaysian streams. The storage estimates determined from the rapid procedures were compared with those from behaviour (or simulation) analysis and Gould's transition matrix method. Limitations in theoretical models result from the basic assumptions upon which they were developed. For empirical models, difficulties arise through the non-representativeness of the basic data. Some procedures are restricted in the range of conditions within which they are applicable. The results indicate that Gould's (gamma) and McMahon's (empirical) procedures provide satisfactory storage estimates for preliminary assessments. 相似文献
9.
Research engineers use two types of energy equations to study single-degree-of-freedom (SDOF) systems subject to earthquake induced ground motions. The first method uses an absolute energy formulation; the second method uses a relative energy formulation. While the relative energy formulation has been used in the majority of previous investigations, this study shows that the absolute energy equation is physically more meaningful. For a given ductility ratio, the input energy demands calculated by both methods are significantly different for both the short and long period ranges although the results are similar in the intermediate period range. A comparison between the analytically predicted absolute input energy of a SDOF system with the experimentally measured input energy of a six-storey braced steel frame shows good correlation. 相似文献
10.
Evaluation of blast-induced ground vibration predictors 总被引：12，自引：1，他引：12
The present paper mainly deals with the prediction of blast-induced ground vibration level at a Magnesite Mine in tecto-dynamically vulnerable hilly terrain in Himalayan region in India. The ground vibration was monitored to calculate the safe charge of explosive to avoid the continuous complaints from the nearby villagers. The safe charge of explosive and peak particle velocity (PPV) were recorded for 75 blast events (150 blast data sets) at various distances. These data sets were used and analysed by the widely used vibration predictors. From the four predictors, vibration levels were calculated and compared with new monitored 20 blast data sets. Again, the same data sets were used to validate and test the three-layer feed-forward back-propagation neural network to predict the PPV values. The same 20 data sets were used to compare the results by the artificial neural network (ANN). Among all the predictors, a very poor correlation was found, whereas ANN provides very near prediction with high degree of correlation. 相似文献
11.
Several parameters have been proposed in the literature for the evaluation of seismic damage. However, in most cases the correlation between results obtained using these parameters and observed damage in structures has not been satisfactory. A parameter for measuring seismic damage previously proposed by the first author is used in this study to analyse a set of 15 accelerograms recorded in 11 earthquakes experienced in different countries. Results using this parameter are compared to global building damage observed during these earthquakes. The use of the parameter proposed here yields results which are consistent with building damage observed in the earthquakes studied. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
12.
地震损失评估与数据库系统 总被引：5，自引：0，他引：5
1989年10月大同-阳高地震后,国家地震局首次组织有关人员进行了震害评估,为政府进行抗震救灾决策提供了科学依据;对加快灾区重建,减少地震损失起了重要作用。本文根据大同-阳高地震的评估经验和近期研究成果,提出了一个震害快速评估实用方法,介绍了震害评估计算程序(EDEP),并以实例说明程序的主要功能和使用方法。最后,为更快地评估地震损失,建议建立重点监测区震害评估数据库系统,并提出数据库系统的建立方法。 相似文献
13.
14.
利用底部剪力法对太原市（基本烈度为８度）一幢５层砖体结构的宿舍楼进行了抗震验算。根据计算结果，对该宿舍楼进行了震害预测，并对其结构的抗震性能给予了定性评价。 相似文献
15.
《Ground Water Monitoring & Remediation》1987,7(4):85-93
In order to avoid contamination of ground water samples by stagnant water in the well bore, it is generally recommended that the well be purged prior to sampling. There is however, a divergence of opinion both on the need for purging and the best methods of purging. This paper describes detailed field tests in which non-reactive tracers were used to examine, from a well hydraulics point of view, the need for purging and also the effectiveness of various purging procedures. Results show that in the permeable geologic materials of the test site, and for the non-reactive tracers, the water within the screened interval will be purged by the natural flow of water through the screen, while the water above will remain stagnant. The volume of water above the screen is referred to here as one bore volume. It,is suggested that with consideration of the required sample volume, the volume of water stored in the screen, the sampling rate, and the position of the sampler intake, dedicated samplers could be used to obtain representative ground water samples without prior purging of the well.
Of the purging procedures tested, pumping from just below the air-water interface in the well, or the method of "complete removal" of the water within the well bore were the only effective means for complete removal of the stagnant water. Using these procedures, it appeared that representative samples could be obtained with the removal of only two to three bore volumes of water. 相似文献
Of the purging procedures tested, pumping from just below the air-water interface in the well, or the method of "complete removal" of the water within the well bore were the only effective means for complete removal of the stagnant water. Using these procedures, it appeared that representative samples could be obtained with the removal of only two to three bore volumes of water. 相似文献
16.
Evaluation of seismic displacements of quay walls 总被引：2，自引：0，他引：2
Sung-Ryul Kim In-Sung Jang Choong-Ki Chung Myoung-Mo Kim 《Soil Dynamics and Earthquake Engineering》2005,25(6):451-459
A new simplified dynamic analysis method is proposed to predict the seismic sliding displacement of quay walls by considering the variation of wall thrust, which is influenced by the excess pore pressure developed in backfill during earthquakes. The method uses the Newmark sliding block concept and the variable yield acceleration, which varies according to the wall thrust, to calculate the quay wall displacement.A series of 1 g shaking table tests were executed to verify the applicability of the proposed method, and a parametric study was performed. The shaking table tests verified that the proposed method properly predicts the wall displacement, and the parametric study showed that the evaluation of a realistic wall displacement is as important as the analysis of liquefaction potential for judging the stability of quay walls. 相似文献
17.
X线CT的性能评估 总被引：2，自引：0，他引：2
张振荣 《CT理论与应用研究》1995,4(2):32-35
Ｘ线ＣＴ自问世以来，以飞快的快速向前发展。世界上各主要生产厂家不断地采用新技术，不断地推出新产品，不断地更新换代。目前我国引进的与国产的各种类型的Ｘ线ＣＴ已经达到一千数百台，而且这个数字还在不断地而且快速地增长。对于如何评价Ｘ线ＣＴ的性能指标无疑是非常重要的。在这篇文章中，作者根据自己的经验与体会对Ｘ线ＣＴ的性能如何评估作了扼要的阐述以供读者参考，特别是对那些正订购或即将订购Ｘ线ＣＴ的医院或许会有 相似文献
18.
This paper presents the results of a study undertaken todetermine the seismic hazard of Lebanon. The seismic hazard evaluation wasconducted using probabilistic methods of hazard analysis. Potential sourcesof seismic activities that affect Lebanon were identified and the earthquakerecurrence relationships of these sources were developed from instrumentalseismology data, historical records, and earlier studies undertaken toevaluate the seismic hazard of neighboring countries. The sensitivityof the results to different assumptions regarding the seismic sources in theLebanese segment and choice of the attenuation relationship wasevaluated. Maps of peak ground acceleration contours, based on 10percent of probability of exceedance in 50 years and 100 years time spans,were developed. 相似文献
19.
地幔主要矿物橄榄石［(Mg089Fe011)2SiO4］的相变与深源地震的解释以及俯冲带和周围地幔的相互作用相关. 其中，形核率和长大率是刻画其相变动力学的两个重要参数. 因为实验技术的原因，目前人们还没有基于实验数据给出橄榄石的形核率. 本文首先通过对挤碰物理图像的分析，对边界形核情形的相变动力学理论中表征挤碰程度的无量纲参数进行了修正. 在此基础上，根据已有的实验资料，首次对橄榄石相变的形核率进行了估计. 通过对形核率数据的拟合，可以得到形核率参数K0和γ1/3. 得到两个形核率参数的变化范围分别为K0=55×1021～87×1027s-1·m-2·K-1，γ1/3=0～020 J·m-2，最佳拟合值为：K0=69×1024s-1·m-2·K-1，γ1/3=016 J·m-2. 相似文献
20.
《水文科学杂志》2013,58(1)
Abstract Abstract The impact of climate change is projected to have different effects within and between countries. Information about such change is required at global, regional and basin scales for a variety of purposes. An investigation was carried out to identify trends in temperature time series of 125 stations distributed over the whole of India. The non-parametric Mann-Kendall test was applied to detect monotonic trends in annual average and seasonal temperatures. Three variables related to temperature, viz. mean, mean maximum and mean minimum, were considered for analysis on both an annual and a seasonal basis. Each year was divided into four principal seasons, viz. winter, pre-monsoon, monsoon and post-monsoon. The percentages of significant trends obtained for each parameter in the different seasons are presented. Temperature anomalies are plotted, and it is observed that annual mean temperature, mean maximum temperature and mean minimum temperature have increased at the rate of 0.42, 0.92 and 0.09°C (100 year)-1, respectively. On a regional basis, stations of southern and western India show a rising trend of 1.06 and 0.36°C (100 year)-1, respectively, while stations of the north Indian plains show a falling trend of –0.38°C (100 year)-1. The seasonal mean temperature has increased by 0.94°C (100 year)-1 for the post-monsoon season and by 1.1°C (100 year)-1 for the winter season. 相似文献