Modal analysis of semiconductor lasers with nonplanar mirrors

We present a formalism for analyzing laser resonators which possess nonplanar mirrors and lateral waveguiding [e.g., an unstable resonator semiconductor laser (URSL)]. The electric field is expanded in lateral modes of the complex-index waveguide and is required to reproduce itself after, one roundtrip of the cavity. We show how the waveguide modes, their gain and loss, and hence the criterion for truncation of the infinite set of modes can be derived from the Green's function of the one-dimensional eigenvalue equation for the waveguide. Examples are presented for three cases of interest - a purely gain-guided URSL, an index-guided URSL, and a gain-guided tilted-mirror resonator. We compare theoretical calculations to previous experiments

Tax reform and the political economy of the tax base

This paper studies the political prospects for reform in a model where the tax base and statutory rate are separate instruments of tax policy. The model suggests that large changes in the tax code may be easier to enact than marginal reforms. The tax base faces a tipping point where even the beneficiaries from tax exemptions support reform. At this tipping point, tax reform is Pareto improving. Politically feasible tax reform occurs when fiscal needs are large, but may nonetheless involve reductions in marginal tax rates. There is strategic complementary in lobbying for tax exemptions, resulting in multiple equilibria. The model’s main predictions are consistent with recent tax reforms in OECD countries

Clausal tripartition, anti-locality and preliminary considerations of a formal approach to clause types

We will see how it is reasonable to speak of a minimum distance that an element must cross in order to enter into a well-formed movement dependency. In the course of the discussion of this notion of anti-localiry, a theoretical framework unfolds which is compatible with recent thoughts on syntactic computation regarding local economy and phrase structure, as well as the view that certain pronouns are grammatical formatives, rather than fully lexical expressions. The upshot will be that if an element does not move a certain distance, the derivation crashes at PF, unless the lower copy is spelled out as a pronominal element. The framework presented has a number of implications for the study of clause-typing, of which some will be discussed towards the end

Mythological Names and dróttkvætt Formulae I: When is a Valkyrie Like a Spear?

This article explores patterns of language use in oral poetry within a variety of semantic formula. Such a formula may vary its surface texture in relation to phonic demands of the metrical environment in which it is realized. Metrically entangled kennings in Old Norse dróttkvætt poetry provide material for a series of case studies focusing on variation in realizing formulae of this type. Old Norse kennings present a semantic formula of a particular type which is valuable as an example owing to the extremes of textural variation that it enables. Focus will be on variation between two broad semantic categories in expressing the formula’s consistent unit of meaning that are otherwise unambiguously distinct: proper names for mythological beings and poetic terms for weapons and armour. This article introduces an approach to kennings as semantic formulae and includes an illustrative case study on kennings meaning ‘battle’ in the last three metrical positions of a dróttkvætt line. The case study is simultaneously used to demonstrate the degree of integration of mythological proper names in the poetic register. This article contains only the first case study of a series. It provides foundations for examining variation in the associative links exhibited by names of mythic beings as a category according to the metrical positions in which a battle-kenning is realized

A Growing Sin-dustry: The History and Effects of Cigarette Excise Taxation and Regulation in the United States

Originating with the gabelle taxes of France during the close of the Albigensian Crusades, excise taxes and regulations on consumer products have historically been used by local and federal governments to generate revenue during periods of war. Following the enactment of the Internal Revenue Act on June 30, 1864, the United States extended their definition of consumer products to include cigarettes and other tobacco products. The United States Federal government justifies cigarette taxes as a method not only to discourage the habit of smoking but also to recover the costs of the negative externalities associated with the “sinful” behavior. Through an analysis of price elasticities as well as individual state taxation and cigarette consumption data, this thesis attempts to explain why increased prices of cigarettes due to excise taxes are not effective deterrents for smokers without additional enforcement of tax-avoidant behaviors. The first section of this study defines excise taxation through historical and contemporary theories. In addition, the analysis chronologically reviews the history of excise taxation and regulation, including those imposed on cigarette and tobacco, in the United States. This chronological review also highlights the evolution of government policy and the acceptability of cigarette consumption in the United States. The second section analyzes tobacco taxation in the United States during the year 2015. The section begins with an overview of the federal governments’ tobacco taxation policies in the nation. The section concludes with a review of differing taxation rates in individual states. The conclusion introduces factors that affect smoking behavior, which will be used in the proceeding econometric analyses. The third section uses an econometric analysis, conducted by John Lovell Jarvis at Wesleyan University, to explain the price elasticity of cigarettes and the impact of tax-induced prices on annual per capita cigarette consumption. The fourth section also illustrates a differing explanation of price elasticity from the perspective of tobacco companies. The final section studies the impact of cigarette taxation in the state of New York as well as the advantages and disadvantages of cigarette excise taxes. The section explores the increases in tax-avoidant behaviors and additional legislation that affect cigarette consumption in New York and the United States as a whole. Using the results from these studies, the conclusion section discusses the effects of cigarette taxation and regulation on consumer smoking behavior in the United States

On parallels and differences between clitic climbing and long scrambling & the economy of derivations

In this paper I show that Clitic Climbing (CC) in Spanish and Long Scrambling (LS) in German (and Polish) are (im-)possible out of the same environments. For an explanation of this fact I propose a feature-oriented analysis of incorporation phenomena. The idea is that restructuring is a phenomenon of syntactic incorporation. In German and Polish, Agro incorporates covertly into the matrix clause and licenses LS out of the infinitival into the matrix clause. Similarily the clitic in Spanish, which is analysed as an Agro-head, incorporates into the matrix clause. I argue that this movement is necessary for reasons of feature-checking, i. e. for checking of an [+R]- or Restructuring-feature. In section 2 I discuss several differences between CC and LS. For example, the proposed analysis correctly predicts that clitics in contrast to scrambled phrases are subject to several serialization restrictions. Throughout the paper I use the term restructuring only in a descriptive sense, in order to describe the phenomenon in question

Parts, Wholes, and Context in Reading: A Triple Dissociation

Research in object recognition has tried to distinguish holistic recognition from recognition by parts. One can also guess an object from its context. Words are objects, and how we recognize them is the core question of reading research. Do fast readers rely most on letter-by-letter decoding (i.e., recognition by parts), whole word shape, or sentence context? We manipulated the text to selectively knock out each source of information while sparing the others. Surprisingly, the effects of the knockouts on reading rate reveal a triple dissociation. Each reading process always contributes the same number of words per minute, regardless of whether the other processes are operating