Washington State University

About: Washington State University is a education organization based out in Pullman, Washington, United States. It is known for research contribution in the topics: Population & Gene. The organization has 26947 authors who have published 57736 publications receiving 2341509 citations. The organization is also known as: WSU & Wazzu.

Chemical and spectroscopic aspects of polymer ablation: Special features and novel directions

Abstract: In 1982, the first reports of laser ablation of polymers were issued almost simultaneously by Y. Kawamura et al.1 and R. Srinivasan et al.2 Srinivasan went on to become a leader in the field of polymer ablation. Srinivasan probably also coined the terms laser ablation and ablative photodecomposition, now in common use. The onset of material removal by laser ablation characteristically occurs at a well-defined laser fluence (energy per unit area). As the fluence is raised above this threshold, the ablation rate increases. The threshold fluence (F0 or Fth) is material and laser wavelength dependent and can vary from tens of mJ cm-2 to more than 1 J cm-2. The discovery of laser ablation of polymers sparked research in this field in many groups around the world. Many aspects of polymer ablation, and laser processing in general, are reviewed by Bauerle.3 Today, commercial applications of polymer laser ablation include the preparation of viaholes in polyimide for multichip modules at IBM4 and the production of inkjet printer nozzles (also polyimide).5 Considerable progress has been made in understanding polymer ablation since the last series of reviews a decade ago.6-8 New developments in polymer ablation include the application of femtosecond laser pulses, vacuum ultraviolet lasers (VUV), and free electron lasers (FEL). Some of these techniques have a great potential for the development of new applications and research tools. Much of this progress is discussed in this and other articles appearing in this special issue of Chemical Reviews. Current research on polymer ablation may be divided into two areas: (i) Applications of laser ablation, novel materials, and techniques. (ii) Studies of ablation mechanisms (databased modeling). The first area will be discussed in detail in this article, while the mechanistic aspects, especially the theoretical part, are discussed in other articles in this special issue. Many experimental methods and experimental polymers have been designed with a view toward improving our understanding of ablation mechanisms. It is often impossible to completely separate experiments designed to illuminate ablation mech† Paul Scherrer Institut. ‡ Washington State University. 453 Chem. Rev. 2003, 103, 453−485

Estimation for Partially Nonstationary Multivariate Autoregressive Models

Abstract: For an m-variate (“partially”) nonstationary vector autoregressive process {Y t }, we consider the autoregressive model Φ(L)Y t = e t , where Φ(L) = I − Φ1 L − … − Φ p L p and det{Φ(z)} = 0 has d < m roots equal to unity and all other roots are outside the unit circle. It is also assumed that rank {Φ(1)} = r, r = m − d, so that each component of the first differences W t = Y t − Y t − 1 is stationary. The relation of the model to error correction models and co-integration (Engle and Granger 1987) is discussed. The process {Y t } has the error correction representation Φ*(L)(1 − L)Y t = −P 2(I r − Λ r )Q 2 1 Y t-1 + e t , where Q(I m − Φ(1))P = J = diag(I d , Λ r ) is in Jordan canonical form and Q' = [Q 1, Q 2]. It follows that the transformation Z t = QY t = [Zt 1t , Z2 2t ] t is such that the d × 1 process Z 1t is nonstationary with Z 1t − Z 1t-1 stationary while Z 2t is stationary. Asymptotic distribution theory for least squares parameter estimators of the model is first considered. A Gaussia...

Struggling with human exemptionalism: The rise, decline and revitalization of environmental sociology

Abstract: The emergence of environmental sociology in the 1970s, the decline of interest it experienced in the the early 1980s, and its revitalization since the late 1980s are described and linked to trends in societal interest in environmental problems. We suggest that the status of the field has been heavily dependent upon societal attention to environmental problems, in part due to the larger discipline’s ingrained assumption that the welfare of modern societies is no longer linked to the physical environment. We also suggest that growing recognition of the reality of global environmental change (GEC) poses a fundamental challenge to this “human exemptionalism paradigm,” and thus offers an opportunity for strengthening sociological interest in the environment. Understanding the causes and consequences of GEC calls for examination of societal-environmental interactions, the fundamental subject matter of environmental sociology. Unfortunately, early sociological work has largely ignored such interactions in favor of analyses of the “social construction” of GEC, Consequently, limitations of a social constructivist approach to GEC (and to environmental problems in general) are discussed, and a more inclusive research agenda is recommended.

Using data envelopment analysis to measure the efficiency of non-profit organizations: A critical evaluation

Abstract: This study examines the potential effects of variable set expansion and data variations upon the efficiency scores generated using the Data Envelopment Analysis (DEA) model. It was found that variable set expansion (either through disaggregation of existing variables or addition of new factors) should produce an upward trend in efficiency scores. In addition, ample opportunity exists for ‘decision-making units’ to increase their efficiency scores through manipulation of reported data. In real-world applications of DEA, these problems must be resolved as much as possible (e.g. increased audit of data) in order to improve DEA's practical usefulness and reliability.