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1.
翁文波院士的信息预测理论体系的创新性及其意义   总被引:13,自引:1,他引:12       下载免费PDF全文
翁文波院士提出的信息预测理论体系是一个具有自主创新的体系.它的创新性表现在下列几个方面:(1)翁先生创造性地提出:认识可划分为三个层次的认识体系:抽象体系、物理体系、信息体系.其中“信息体系”是翁先生第一个提出的;(2)对数据基本性质的新认识,特别是指出自然数、整数在研究和预测中的重要性;(3)翁先生新提出信息预测,它与统计预测有很大不同等等.翁先生的信息预测理论在天灾预测实际中取得了丰硕的成功预测成果.  相似文献   

2.
The geophysical system of horizontal layers may be considered as a large scale system. A large class of systems is identified which are equivalent to the geophysical processes in horizontal layering. The property of hierarchical aggregation of layers forms a convenient framework within which the peculiarities of such systems can be studied. Geophysical processes in multilayered media may serve as a reference physical model for a specified class of large scale systems, in order to take advantage and to apply geophysical methods of data processing, system analysis, and parameter identification. Specified large scale systems are decomposable, like geophysical systems, by use of recursive schemes. A category particulary susceptible to such a decomposition is any polynomial which is stable inside the unit circle. Sophisticated geophysical concepts, such as anisotropy, equivalence, and disappearance, can be used to approximate or to simplify the system by vanishing or adjusting the decomposition coefficients.  相似文献   

3.
Selection of ground motion time series and limits on scaling   总被引:4,自引:0,他引:4  
A procedure to select time series for use in non-linear analyses that are intended to result in an average response of the non-linear system is proposed that is not based simply on magnitude, distance, and spectral shape. A simple model of a yielding system is used as a proxy for the non-linear behavior of a more complicated yielding system. As an example, Newmark displacements are used as a proxy for more complex slope-stability models. The candidate scaled time series are evaluated to find those that yield a response of the simple non-linear system that is near the expected response for the design event. Those scaled time series with responses near the expected value are selected as the optimum time series for defining average response even if the scale factors are larger than commonly accepted (e.g. scale factors >factor of 2).  相似文献   

4.
依据青藏高原东北部地区的大震 (MS≥ 7)、大震形变带、活动断裂和活动构造体系的资料 ,以地球系统科学、地质力学、地震地质学、现代地震学的理论和方法为主线 ,对该区内大震的“共性”进行了探讨 ,提出了具有三维空间动态的区域地壳现今构造形变系统的新概念 ,并对该区内地震的形成机制、分布规律等科学问题提出了新的见解 .  相似文献   

5.
In this study, domestic wastewater was used as the electrolyte. The work was carried out with an up-flow tubular reactor, made of stainless steel that was used as cathode, while the anode electrode material was aluminum and varying values of flow regime (25, 50, 75 and 100 mL/s for continuous system), initial pH value (5, 6, 7 and 7.8) and current intensity (10, 15 and 20 A) were applied. For domestic wastewater with natural pH, the effluent pH was >9 in the batch system, while in the continuous system the pH was 8–8.5. Likewise, while the effluent temperature was up to 60°C in the batch system, it was at most 35°C in the continuous system. However, the energy consumption values in the continuous system were considerably lower compared with the batch system. At a current intensity of 10 A, 80 kWh of energy per unit volume was consumed in the batch system, while it was 50 kWh for the continuous system. The present results show that the batch system can be used for small wastewater streams whereas the continuous system can be used for large wastewater streams for domestic wastewater treatment.  相似文献   

6.
In a previous study (Kaplan H, Seireg A., Int. J. Comput. Appl. Technol., 2000; 13 (1/2): 25–41), the authors proposed a base isolation system for earthquake protection of structures.The system incorporates spherical supports for the base, a specially designed spring‐cam system to keep the base rigidly supported under normal conditions and to allow it to move for the duration of the earthquake under the constraint of a spring with optimized stiffness characteristics. A single‐degree‐of‐freedom structure was considered to investigate the feasibility of the concept. The simulation of the system response shows a 20 times reduction of the transmitted force as a result of using the proposed design in the considered case. This paper extends the previous study to the case of a 40‐storey steel structure subjected to the Taft as well as El Centro earthquakes. A 7.5 and 6 times reduction of the maximum transmitted force was achieved for the considered disturbances, respectively, without any adverse effects due to the tilting moment which is inherent in this type of base isolation. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

7.
8.
High-rise buildings are an efficient solution to meet the housing challenges of global urbanization that is happening at an incredible pace. Code-based seismic design philosophies are aimed at achieving collapse-prevention under major earthquakes, implying extensive structural damage associated with important losses. A number of high-performance systems have been investigated for enhancing the resilience of high-rise buildings whose design is especially challenging due to higher-mode effects even when a flexural mechanism is formed at the base of the structure. To this end, this paper proposes a new concept consisting of a three-dimensional uncoupled rocking and shear mechanism system for high-rise buildings where reinforced concrete (RC) core walls are used as the lateral-force-resisting system. The proposed system provides a dual-mechanism at the base that independently limits both overturning moments (OTMs) and shear forces and thus more effectively mitigates higher-mode effects. The characteristic mechanics of the proposed system are first studied through an idealized model. A physical embodiment is then designed, detailed, and validated through advanced models and extensive nonlinear dynamic analyses. A 42-story RC core-wall building that is located in Los Angeles and was studied as part of the PEER Tall Buildings Initiative is used as a reference structure in this study. Results confirmed that the proposed system eliminates damage at the base of the walls and minimizes the inelastic demands over the height of the building. In a general sense, the proposed concept provides a framework in which the intended dual mechanism can be implemented to a wider range of high-rise structures.  相似文献   

9.
本研究运用DSP高速数字信号处理器的实时信号处理与控制技术,研究了基于速度控制法、OS数值积分法和相应的实验误差控制法的子结构拟动力实验系统。该试验系统对动力加载装置采用速度控制,在加载过程中考虑了加载速率对实验结果的影响,使隔震橡胶支座的速度相关性能在试验中得到充分体现,同时采用OS数值积分法,充分地减少了试验的时滞误差,提高了试验精度。并通过不同加载速率的子结构拟动力实验研究了天然橡胶支座、高阻尼橡胶隔震支座和超高阻尼橡胶隔震支座对桥梁的隔震效果,在对实验结果进行分析对比后,定量地研究了不同的加载速率对隔震桥梁子结构拟动力实验结果的影响。  相似文献   

10.
A superiority-inferiority-based inexact fuzzy-stochastic chance-constrained programming (SI-IFSCCP) approach is developed for supporting long-term municipal solid waste management under uncertainty. Through SI-IFSCCP, multiple uncertainties expressed as intervals, possibilistic and probabilistic distributions, as well as their combinations, could be directly communicated into the optimization process, leading to enhanced system robustness. Through tackling fuzziness and two-layer randomness, various subjective judgments of many stakeholders with different interests and preferences could be extensively reflected, guaranteeing a lower degree of biases during data sampling and a higher degree of public acceptance for the generated plans. Two levels of system-violation risk could also be reflected by SI-IFSCCP, reflecting the relationship between economic efficiency and system reliability. A two-step solution method with improved computational efficiency is proposed for SI-IFSCCP. To demonstrate its applicability, the developed methodology is then applied to a long-term municipal solid waste management problem. Useful solutions have been generated. Satisfactory waste flow plans could be identified according to system conditions and policy inclination, supporting in-depth tradeoff analyses between system optimality and reliability as well as between economic and environmental objectives.  相似文献   

11.
高柔结构在地震或风荷载作用下会产生很大的振动,本文提出一种控制高柔结构振动的新方法--摆、油阻尼器体系,并在振动台进行了模拟试验,结果表明:该方法可使结构振动位移幅值减小50%,在试验中变换了体系的各有关参数,研究了摆长,质量比,碰击间隙对减振效果的影响,文中详细研究了油阻尼器的工作过程及减振机理,从理论上初步分析了摆,油阻尼器体系减振原因,提出了可供实际设计参考的方法和原则。  相似文献   

12.
地震学中的一个主要问题是如何将原始的震源信号从其他影响中分离出来。讨论了地震波在传播过程中可能引起波形变化的一些因素以及记录系统和采样处理过程所产生的影响,介绍了地震信号处理中的一般原理和概念,通过对简单的RC滤波器的讨论,揭示了系统理论的一些基本概念,如线性时间不变系统、傅里叶变换和拉普拉斯变换、褶积、频率响应函数、传递函数和极点等,为讨论数字地震信号的处理奠定了基础。  相似文献   

13.
针对上海市超限高层建筑工程实例,收集整理了相关设计信息,构建了能够表征这些设计信息的数据表并形成了数据库。鉴于传统的管理信息系统不能够空间表示,提出了一种新型的基于Arc-GIS的信息系统,同时引入了贝叶斯网络,以数据库样本为基础进行结构选型。实践证明,该系统充分利用了计算机的存贮、计算、统计、共享以及空间显示功能,贝叶斯网络为超限高层建筑结构体型优选提供了一种新的方法,对超限高层建筑工程的设计改进和规范的完善都具有一定的实际意义。  相似文献   

14.
A design strategy for control of buildings experiencing inelastic deformations during seismic response is formulated. The strategy is using weakened, and/or softened, elements in a structural system while adding passive energy dissipation devices (e.g. viscous fluid devices, etc.) in order to control simultaneously accelerations and deformations response during seismic events. A design methodology is developed to determine the locations and the magnitude of weakening and/or softening of structural elements and the added damping while insuring structural stability. A two‐stage design procedure is suggested: (i) first using a nonlinear active control algorithm, to determine the new structural parameters while insuring stability, then (ii) determine the properties of equivalent structural parameters of passive system, which can be implemented by removing or weakening some structural elements, or connections, and by addition of energy dissipation systems. Passive dampers and weakened elements are designed using an optimization algorithm to obtain a response as close as possible to an actively controlled system. A case study of a five‐story building subjected to El Centro ground motion, as well as to an ensemble of simulated ground motions, is presented to illustrate the procedure. The results show that following the design strategy, a control of both peak inter‐story drifts and total accelerations can be obtained. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

15.
A coastal prediction system for Tampa Bay, comprised of a numerical circulation model and Lagrangian particle transport model, rapidly produces hindcast/forecast simulations that alert authorities to high impact areas following the introduction of hazardous material into the bay. The effectiveness of the prediction system as an event response tool is evaluated during an anhydrous ammonia spill. A week-long simulation predicts the trajectory of the material due to winds and currents. Physical transport of the model particles alternates from being tidally driven to being driven both by wind action and residual circulation. A forecast simulation showing particle distribution drove field sampling that resulted in the detection of a Pseudo-nitzschia bloom likely initiated from excess ammonium in the bay. An online component of the coastal prediction system is in development to better manage response and mitigation efforts for future hazardous material spills in Tampa Bay.  相似文献   

16.
For a proper response spectrum analysis of a secondary system with multiple supports, the seismic inputs are required to be defined in terms of the auto and cross floor response spectra. If no feed-back or interaction effect from the secondary system to its supporting primary structure is suspected, these inputs can be developed by a direct analysis of the supporting structure alone. However, sometimes the effect of the interaction on the secondary system response can be quite significant. Herein, a method is developed to incorporate the feed-back effect, through proper modification of the interaction-free floor spectrum inputs. The interaction coefficients are used to effect such modifications in different floor spectral quantities. A procedure for the calculation of the interaction coefficients is proposed. The modified floor spectra when used as inputs to the secondary system do introduce the interaction effect in the secondary system response. A successful application of this method is demonstrated by numerical examples of secondary systems with three different secondary-to-primary system mass ratios.  相似文献   

17.
In this paper we describe a warning system based on statistical analysis for the purpose of monitoring ground deformation at the Sciara del Fuoco (Stromboli Volcano, Sicily). After a statistical analysis of ground deformation time-series measured at Stromboli by the monitoring system known as THEODOROS (THEOdolite and Distancemeter Robot Observatory of Stromboli), the paper describes the solution adopted for implementing the warning system. A robust statistical index has been defined in order to evaluate the movements of the area. A fuzzy approach has been proposed to evaluate an AI (Alarm Intensity) index which indicates the level of hazard of the Sciara del Fuoco sliding.  相似文献   

18.
为了更好地开展人工地震测深工作,研制了携带式多道数字化观测系统,由拾震器、前置放大滤波器、对时装置和多道数字化数据采集记录器SCJ-8等组成。主要性能是:有1-8个输入通道;带宽为2-30Hz;动态范围约110db;A/D和D/A皆为12位;非线性失真约0.5%;串音约-90db;等待功耗约2W;记录功耗约6W;能同时输出数字和模拟数据,可直接与计算机接口;时间服务用晶控数字钟;有多种控制与监测功能。实验观测表明,该系统性能好,功能全,工作基本可靠,已达到原设计要求,为人工地震测深增添了新的观测记录仪器。 文中对系统的主机SCJ-8作了较详细地介绍,给出了系统在野外试验观测时记录到的地震波形。  相似文献   

19.
In this paper a comprehensive investigation on the dynamic characteristics of turbine–generator–foundation systems is performed. All the major components of the system, including turbine–generator casing, shaft, rotors, journal bearings, deck, piers, foundation mat, piles, and soil medium, have been included. Full interaction between the turbine–generator set, the foundation superstructure, and the soil medium, is considered. A hybrid method is used to establish the mathematical model for the turbine–generator-foundation system. The analysis is conducted in the frequency domain through complex frequency response analysis. The response in the time domain is obtained by Fourier transform. The seismic excitation is represented as the control motion on the ground surface, which is generated as an artificial earthquake. A 300 MW turbine-generator-foundation system is analysed under excitations from rotor unbalances and earthquakes. The influence of turbine-generator casing and soil anisotropy on the response of the system is explored. It is found that the presence of casing and soil anisotropy strongly influences the displacements and internal forces of the system under rotor unbalance excitation. Under seismic excitation, however, although the presence of casing and soil anisotropy does affect the displacements of the system, their effect on the internal forces of the system is minimal.  相似文献   

20.
“九五”期间,辽宁省地震局按照中国地震局的统一部署,应用先进的数字技术、网络技术和计算机技术,对原有的前兆与地震观测的模拟技术系统进行了改造,新建了辽宁省地震信息网络系统和防震减灾指挥中心,这是辽宁省第一次这样大规模地对防震减灾技术系统进行建设和改造。本文对“九五”重点项目的任务、技术系统构成及建设成果进行了阐述。  相似文献   

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