Statistical aspects of earthquake source parameter estimation in the presence of signal generated noise

Seismologists have developed models which relate observed ground motion to the physical parameters of the earthquake which caused it These models are based on an idealized model which approximates the behavior of the real earth. In this paper we will examine some of the uncertainties which cause observations to deviate from such models. These uncertainties include presence of contaminating noise and the wave scattering caused by the inhomogeneous nature of the earth. By modeling such uncertainties statistically, we are able to formulate a maximum -likelihood type procedure for model fitting and address the such issues as of the computation of standard errors and graphical diagnostics for goodness-of-fit.

The paper illustrates the procedure on observations from a small Califomian earthquake.     

下一代预警机雷达技术

在现代信息化战争中,预警机雷达作为战场信息获取和指挥控制的关键节点,发挥着不可替代的作用.面对日益复杂的战场环境,作战体系对预警机雷达提出了更高的要求;同时,随着基础技术的不断发展,预警机雷达所能实现的功能也日趋丰富,文中探讨了其应用功能的变化,并对其功能实现上所需解决的关键技术进行了说明.     

信号检测论在内隐学习研究中的应用

信号检测论引入心理学研究领域是对传统心理物理学方法的一个发展.在内隐学习实验中,信号检测论的两个指标d'和β分离了个体的感受性和主观判断标准,利用d'和β的共变关系证实了内隐学习的存在和内隐学习的特征.本文探析了内隐学习研究中应用信号检测论(正态分布信号检测模型)的逻辑机理.从被试的心理行为反应上微观地分析了用SDT揭示无意识领域的可行性.     

《管子》名学思想新议——从语词符号角度

《管子》的"名"并不是传统所理解的"概念",而是一种用以标记、指称事物的名称符号。在《管子》中包含了较丰富的语词符号思想,它具体探讨了"名"的生成及其作用、语词符号与指称对象的关系以及规范这种关系的意义等问题。《管子》的语词符号思想,对于当今的符号学理论研究,仍具有重要启迪意义。     

不完全信息下再制造逆向供应链的定价与协调研究

本文探讨了回收量随机情况下的单一制造商和两个零售商组成的再制造逆向供应链系统的定价策略。在完全信息下,分别得到了Stackelberg博弈和联合博弈下的可行策略集合及可行解。在不完全信息下,运用信号甄别方法及激励相容约束得到了两个最优定价合同。研究表明:定价合同可以有效避免逆向选择问题,保证回收市场的稳定性;通过签订合同,制造商和零售商的利润均有所增加;制造商可通过零售商的履约表现控制其回收量,并对未完成任务的零售商进行惩罚;高运营成本零售商会不断降低运营成本以增加利润。     

GMM with Many Moment Conditions

This paper provides a first order asymptotic theory for generalized method of moments (GMM) estimators when the number of moment conditions is allowed to increase with the sample size and the moment conditions may be weak. Examples in which these asymptotics are relevant include instrumental variable (IV) estimation with many (possibly weak or uninformed) instruments and some panel data models that cover moderate time spans and have correspondingly large numbers of instruments. Under certain regularity conditions, the GMM estimators are shown to converge in probability but not necessarily to the true parameter, and conditions for consistent GMM estimation are given. A general framework for the GMM limit distribution theory is developed based on epiconvergence methods. Some illustrations are provided, including consistent GMM estimation of a panel model with time varying individual effects, consistent limited information maximum likelihood estimation as a continuously updated GMM estimator, and consistent IV structural estimation using large numbers of weak or irrelevant instruments. Some simulations are reported.     

Marginal Trust in Risk Managers: Building and Losing Trust Following Decisions Under Uncertainty

Although a considerable amount of research has examined correlates of baseline public trust in risk managers, much less research has looked at marginal changes in public trust following specific events. Such research is important for identifying what kinds of events will lead to increases and decreases in public trust and thus for understanding how trust is built and lost. Using a taxonomy based upon signal detection theory (SDT), the current article presents two experimental studies examining marginal trust change following eight different types of events. Supporting predictions, cautious decisionmakers who accepted signs of danger (Hits and False Alarms) were more likely to be trusted than those who rejected them (All Clears and Misses). Moreover, transparency about an event was associated with higher levels of marginal trust than a lack of transparency in line with earlier findings. Contrary to predictions, however, trust was less affected by whether the decisions were correct (i.e., Hits and All Clears) or incorrect (i.e., False Alarms and Misses). This finding was primarily due to a "False Alarm Effect" whereby Open False Alarms led to positive increases in trust despite being incorrect assessments of risk. Results are explained in terms of a cue diagnosticity account of impression formation and suggest that a taxonomy of event types based on SDT may be useful in furthering our understanding of how public trust in risk managers is gained and lost.     

炮位雷达智能应答器的设计与实现

介绍了一种炮位雷达智能应答器的系统构成、基本原理、主要功能及其实现.该智能应答器运用主控计算机计算出弹道仿真轨迹,再用可编程门阵列对接收的雷达信号进行数字信号处理,根据弹道轨迹产生调制的雷达目标回波信号.该智能应答器已完成了对炮位雷达信号的测试,取得了令人满意的效果.     

“数字信号处理”课程教学改革探索与实践

针对＂应用型＂本科教学特点及目标定位,分析了数字信号处理课程教学目前的现状,结合本课程的教学实践,从教学体系、教学内容以及考核方式等方面提出了教学改革方案并进行了初步尝试。     

Statistical Analysis of Non Linear Least Squares Estimation for Harmonic Signals in Multiplicative and Additive Noise

Abstract

This article concerns the stochastically constrained linear model under a biased assumption. We propose a quasi-stochastically constrained least squares estimator. Furthermore, we provide the expectation of this estimator, demonstrate its consistency and asymptotic normality. In the end of the article, the simulation study of the new estimator shows that it is superior to the least squares estimator, ridge estimator, and the linear constrained estimators under certain conditions by comparing the mean squared errors of these estimators.