Warpage eliminated in copper-clad microwave circuit laminates

Cryogenic treatment of laminated copper-clad microwave circuit boards eliminates stresses that cause warpage when a circuit is etched on one side of the board. After etching, the stresses may be eliminated to reduce warpage

A Dynamic Approach to Linear Statistical Calibration with an Application in Microwave Radiometry

The problem of statistical calibration of a measuring instrument can be framed both in a statistical context as well as in an engineering context. In the first, the problem is dealt with by distinguishing between the 'classical' approach and the 'inverse' regression approach. Both of these models are static models and are used to estimate exact measurements from measurements that are affected by error. In the engineering context, the variables of interest are considered to be taken at the time at which you observe it. The Bayesian time series analysis method of Dynamic Linear Models (DLM) can be used to monitor the evolution of the measures, thus introducing an dynamic approach to statistical calibration. The research presented employs the use of Bayesian methodology to perform statistical calibration. The DLM's framework is used to capture the time-varying parameters that maybe changing or drifting over time. Two separate DLM based models are presented in this paper. A simulation study is conducted where the two models are compared to some well known 'static' calibration approaches in the literature from both the frequentist and Bayesian perspectives. The focus of the study is to understand how well the dynamic statistical calibration methods performs under various signal-to-noise ratios, r. The posterior distributions of the estimated calibration points as well as the 95% coverage intervals are compared by statistical summaries. These dynamic methods are applied to a microwave radiometry data set.Comment: 26 pages, 10 figure

Dynamic Bayesian Nonlinear Calibration

Statistical calibration where the curve is nonlinear is important in many areas, such as analytical chemistry and radiometry. Especially in radiometry, instrument characteristics change over time, thus calibration is a process that must be conducted as long as the instrument is in use. We propose a dynamic Bayesian method to perform calibration in the presence of a curvilinear relationship between the reference measurements and the response variable. The dynamic calibration approach adequately derives time dependent calibration distributions in the presence of drifting regression parameters. The method is applied to microwave radiometer data and simulated spectroscopy data based on work by Lundberg and de Mar\'{e} (1980)

Stress relief of copper clad microwave circuit laminates to reduce and prevent warpage

Stress relief of copper-clad microwave circuit laminates to reduce and prevent warpag

Euro public debt and the markets: sovereign fundamentals and CDS market dynamics.

At the onset of the crisis, euro area – like all Organisation for Economic Co-operation and Development (OECD) countries – public finances have massively inflated, as is typical in financial crises. The major difference with the past is threefold: the synchronicity across countries of the increase, the debt levels which have been reached; and the existence of credit default swap (CDS) market which has influenced the dynamic of sovereign trading. In this note, we review quickly fundamentals before highlighting the role of the CDS market and the implications for sovereign trading.

Corporate Restructuring and Corporate Auctions

We study 298 firms that announce the intent to consider restructuring during the 1989 to 1998 period. We find that the actions taken subsequent to the initial restructuring consideration are equally divided between (i) being acquired, (ii) divesting one or more subsidiaries, or (iii) either terminating the process or declaring bankruptcy. There is a greater completion rate in the second half of the sample, which suggests that economywide factors influence the restructuring decision. For the average firm in the sample, restructuring is a positive net present value decision, although sustained positive shareholder returns accrue only to the firms that actually complete restructuring. For a sub-sample of firms that are acquired, we detail the private auction process that is initiated and conducted by the selling firms and their investment banks. In the private auction, 80 percent of the selling firms have multiple bidders, even though only 20 percent of these cases have more than one publicly announced bidder. The depth of the private auction affects the runup of stock prices prior to the formal acquisition offer, suggesting a reinterpretation of the traditional explanations for the variation in premiums across target firms. The use of private auctions by selling firms also suggests one reason for the absence of toeholds in many mergers as well as the occurrence of multiple public bids even when there is only a single public bidder in a merger.

Valuing the Process of Corporate Restructuring

We study the process of corporate restructuring for a sample of 298 firms during the 1989-98 period that announce that they are considering restructuring alternatives. We find that restructuring is a lengthy process, with the majority of the restructuring period occurring prior to any definitive proposals for corporate change. Only 70 percent of the firms that initially propose restructuring later make a definitive proposal to sell either all or part of the firm, with other firms taking themselves out of play or declaring bankruptcy. Hence, the market reaction to the initial restructuring announcement underestimates the full wealth effects of completed restructurings. The estimate of the full value of restructuring across the sample firms averages 7.5 percent, with the greatest gains of 30 percent accruing to firms that are acquired. The average gain for the full restructuring period for firms divesting a unit is 5 percent, which is roughly double that estimated for the initial announcement in prior studies of corporate divestitures.

Electromagnetic wave characteristics of a fully ionized gas Final report

Electromagnetic wave propagation in fully ionized ga

Parental Investment and Elite Family Structure in Preindustrial States: A Case Study of Late Medieval-Early Modern Portuguese Genealogies

In this paper I examine the idea that patriarchal family structure among elites in stratified societies originates as a form of parental investment favoring male children. Patriliny and restricted inheritance among 15th- and 16th-century Portuguese nobility are analyzed as reproductive strategies aimed at maximizing lineage survival and posterity in the face of high mortality. Demographic data derived from genealogies show that among the high nobility, males out reproduce females,whereas among the lower nobility, females outreproduced males, and that the tendency to concentrate investment in male offspring correspondingly increases with status. This family structural arrangement has the societal effect of generating intense competition among males for available titles, which results in increased warfare mortality among men and indirectly in the increased claustration of women