直扩/跳频测控信号伪码跟踪抗干扰性能分析

研究了直扩/跳频测控信号伪码跟踪的抗干扰性能,通过加权处理使其归结为分析 干扰条件下直扩信号伪码跟踪性能。采用鉴相曲线的过零点偏移表示干扰对跟踪的影响,推 导了伪码跟踪的最大干扰误差表达式。以单音信号作为输入干扰,对最大干扰误差进行了理 论分析,得出了音频干扰对伪码跟踪的影响规律。仿真结果表明,理论分析与仿真结果吻合 较好,验证了理论分析的正确性。     

Analysis of wage flexibility across the Euro Area: evidence from the process of convergence of the labour income share ratio

This article analyses wage flexibility as a factor in the unemployment rate across 12 Euro Area countries. We use extensive evidence pertaining to the countercyclical behaviour of the labour income share ratio to estimate its equilibrium value in the long run. This measure is calculated using a hybrid New Keynesian Phillips curve. Additionally, by using spatial econometrics, we can incorporate into the study the interdependence in the inflation among the countries. As a result, we identify countries that might see an improvement in their employment rates by improving their wage flexibility. We also identify countries with high unemployment that is not a consequence of a lack of wage flexibility.     

Debt,Equity and Hybrid Decoupling: Governance and Systemic Risk Implications

We extend here our prior work, which focused on equity decoupling ( Hu and Black, 2006, 2007, 2008 ), by providing a systematic treatment of debt decoupling and an initial exploration of hybrid decoupling. Equity decoupling involves unbundling of economic, voting, and sometimes other rights customarily associated with shares, often in ways that may permit avoidance of disclosure and other obligations. We discuss a new U.S. court decision which will likely curtail the use of equity decoupling strategies to avoid large shareholder disclosure rules. Debt decoupling involving the unbundling of the economic rights, contractual control rights, and legal and other rights normally associated with debt, through credit derivatives and securitisation. Corporations can have empty and hidden creditors, just as they can have empty and hidden shareholders. ‘Hybrid decoupling’ across standard equity and debt categories is also possible. All forms of decoupling appear to be increasingly common. Debt decoupling can pose risks at the firm level for what can be termed ‘debt governance’? the overall relationship between creditor and debtor, including creditors' exercise of contractual and legal rights with respect to firms and other borrowers. Widespread debt decoupling can also involve externalities and therefore create systemic financial risks; we explore those risks.     

A proposition of generalized stochastic Milevsky–Promislov mortality models

The aim of this article is to propose a new approach to the estimation of the mortality rates based on two extended Milevsky and Promislov models: the first one with colored excitations modeled by Gaussian linear filters and the second one with excitations modeled by a continuous non-Gaussian process. The exact analytical formulas for theoretical mortality rates based on Gaussian linear scalar filter models have been derived. The theoretical values obtained in both cases were compared with theoretical mortality rates based on a classical Lee–Carter model, and verified on the basis of empirical Polish mortality data. The obtained results confirm the usefulness of the switched model based on the continuous non-Gaussian process for modeling mortality rates.     

Practical estimation of multivariate densities using wavelet methods

This paper describes a practical method for estimating multivariate densities using wavelets. As in kernel methods, wavelet methods depend on two types of parameters. On the one hand we have a functional parameter: the wavelet Ø (comparable to the kernel K ) and on the other hand we have a smoothing parameter: the resolution index (comparable to the bandwidth h ). Classically, we determine the resolution index with a cross-validation method. The advantage of wavelet methods compared to kernel methods is that we have a technique for choosing the wavelet Ø among a fixed family. Moreover, the wavelets method simplifies significantly both the theoretical and the practical computations.     

Further remarks on totally ordered representable subsets of Euclidean space

We introduce the property of ? -norm-boundedness on totally ordered subsets of Euclidean spaces. We show that when a closed subset X of the Euclidean space ⁿ, endowed with a continuous total order ?, is ? -norm-bounded, the order topology and the induced Euclidean topology must coincide on X. This generalizes a recent result by Beardon, proved on connected totally ordered subsets of Euclidean space, because on totally ordered closed subsets of ⁿ connectedness is a particular case of ? -norm-boundedness. We also analyze necessary and sufficient conditions for the coincidence of both topologies, and discuss some extension to the infinite-dimensional context.     

中国改革过程中的"过渡性杂种"及其演化意义——以股权分置为例

改革过程中一定会出现一些无法用标准经济学解释的现象,包括"过渡性杂种".股权分置就是典型之一.由于改革之初约束条件的限制,我国资本市场采取了股权分置的制度安排.这是一种合理的安排,虽然它内生着制度性的缺陷.随着约束条件的变化,股权分置也完成了其历史使命.由此可见,中国的改革实质上是一个不断产生"过渡性杂种"、又不断解决"过渡性杂种"的过程.在演化经济学意义上,这是一个不断产生新奇,又使新奇不断归于平常的过程.在对待"过渡性杂种"问题上,我们既要反对悲观主义倾向,又要反对浪漫主义倾向.     

Exploring spatial vulnerability: inequality and agency formulations in social space

Abstract

The authors derive from critical urban geography and consumer research on vulnerability to investigate the ways in which vulnerability within social space is shaped and negotiated. Multiple power dynamics and ideological tension around the production and consumption of social space are explored through diverse examples within the contexts of spaces of consumption, public space as shared good and digital space. The authors offer a conceptualisation of spatial vulnerability and a framework to understand, critique and transform socio-spatial disadvantages. The spatial perspective offered in this article illuminates the ways in which marketplace vulnerability can be institutionalised and become pervasive through and within spaces of everyday life. Yet, the creative and radical potential of social space in managing spatial disadvantages is also explored along with theoretical, managerial, public policy and practical implications.     

Entry timing and innovation strategy in feature phones

Research summary : This inductive study examines how firms make decisions about the timing of innovations, focusing on the mobile handset industry during the feature‐phone era. Through qualitative and quantitative data, we reveal how individual technology‐entry decisions are influenced by a portfolio‐level timing preference, and how this preference informs other aspects of innovation strategy, too. Early movers address greater, more uncertain revenue opportunities with broader, less selective innovation portfolios. Conversely, late movers target lower, more certain revenue opportunities with narrower, more selective portfolios. While timing per se seems unrelated to performance, a timing‐strategy alignment is. Future research on the equifinal configurations we propose—broad/nonselective for early movers and narrow/selective for late movers—could thus help resolve the debate about the link between timing and performance. Managerial summary : We study how firms make decisions about the entry of new product features, in this case mobile phone technologies. During development firms weigh the scale and likelihood of features' commercial success. Some firms display a preference for earlier entry, which offers temporary monopoly rewards if uncertainty resolves favorably, while others tend to opt for later entry, which offers greater certainty but lower rewards due to competitive preemption. The innovation portfolios of these companies thus pursue differently structured opportunities, bringing about different strategic approaches. Since early movers aim for big hits to compensate for a higher failure rate, they launch a broader set of features and exert little selective pressure on the development portfolio. By contrast, late movers' lower payoffs reduce their tolerance for failure, making them launch fewer features and emphasize selectiveness; i.e., they invest in learning from the resolution of uncertainty so as to choose features more discriminately. When we examine innovation performance, timing has no significant effect but matching timing with feature breadth does. Copyright © 2015 John Wiley & Sons, Ltd.     

Intrinsic Persistence of Wage Inflation in New Keynesian Models of the Business Cycles

We derive and estimate a New Keynesian wage Phillips curve that accounts for intrinsic inertia. In line with microevidence on wage setting, we consider a wage‐setting model featuring an upward‐sloping hazard function, based on the notion that the probability of resetting a wage depends on the time elapsed since the last reset. Our wage Phillips curve embeds also backward terms. We test the hazard function slope using generalized method of moment estimation. Then, placing our equation in a small‐scale New Keynesian model, we investigate its dynamic properties using Bayesian estimation. Model comparison shows that our model outperforms commonly used alternative methods to introduce persistence.