Progress on the Direct Strength Method

The Direct Strength method is a new design procedure for cold-formed steel members. The method employs elastic buckling solutions for the cross-section, instead of the element-by-element plate buckling solutions used in traditional design. The use of cross-section elastic buckling solutions insures inter-element compatibility and equilibrium. The Direct Strength method uses strength formulas on the gross section, similar to conventional column curves, for capacity prediction in local and distortional buckling. This avoids effective section calculations altogether. The reliability of the Direct Strength method is demonstrated for a broad selection of beams and columns by comparison with existing test data. Extension of the method to beam-columns is discussed and a solution proposed and demonstrated. Areas needing further research for final implementation are highlighted. The Appendix to the paper provides detailed specification style language appropriate for employing the Direct Strength method for the design of beams and columns

Causes of Wage Increases in Swedish Manufacturing. A Remarkable Case of Regular Behaviour

The present study is a theoretical and empirical investigation into the aggregate wage dynamics of Swedish manufacturing. It contains three essential results: a rigorous search theoretical model of the wage behaviour of firms is presented and adapted for application to aggregate data the implications of the model are confirmed by Swedish data for manufacturing industry and a stable wage drift equation is demonstrated to have existed since the mid-sixties the model is consistent with the findings of earlier postwar empirical research on wage drift in Sweden and provides them with a more satisfactory theoretical interpretation

Wages and Labour Scarcity: The Microfoundations of the Determination of Factor Shares

It was early noted that the Phillips Curve explanation of wage dynamics lacks a solid microeconomic basis. As the explanatory unemployment variable in the Phillips relation is intuitively to be regarded as an indicator of labour scarcity, several authors have argued that the determination of factor shares (the wage/profit ratio) ought to be the logical intermediate step between unemployment and wage inflation. Contributions by Kuh, Solow and Stiglitz in the late sixties follow this line of thought. As soon as wage-setting by firms instead of the impersonal forces of excess demand has been considered, problems have arisen, however. Given the ubiquity of diminishing returns to labour in the short run in static economic models, it is hard to derive the desired result that the wage share increases when unemployment falls. Monopolistic price-setting among firms can only yield such a result, if arbitrary rules for mark-up pricing are enforced. Even more disappointing, the temporarily monopsonistic firm of labour market search models has been shown to increase its (real) wage, when it faces larger flows of unemployed job applicants. The aim of this paper is to show that search theory easily yields the result that factor shares turn in favour of wages, when unemployment falls. The only important prerequisite for this result is that money wages are treated as downward rigid. The analysis remains valid when firms experience constant returns to labour in the short run (up to a capacity limit or to a demand constraint). In fact, my analysis predicts that with such a simple, but presumably relevant, production technology, factor shares are determined by the stock of unfilled vacancies, which in turn is partly determined by the unemployment stock. As intuition says the share of wages in value added increases with the stock of vacancies and decreases with unemployment

Search Theory, Downward Money Wage Rigidity and the Micro Foundations of the Phillips Curve

The present paper has two aims. The first one concerns primarily an issue of method. I set up and analyse an explicitly stochastic model of the optimal behaviour of a firm, which recruits from a search labour market. The second aim of my paper concerns very much an issue of substance in economics. I show that when the firm is not allowed to decrease its money wage, its optimal response to lower unemployment is to increase its wage, if a plausible (and testable) condition with regard to its expected horizon is met. Hence search theory predicts the existence of a micro Phillips relation under plausible assumptions

The Wage Policy of a Firm when Recruitment is a Wage Dependent Poisson Process and Wages are Downward Rigid

The paper contains an analysis of a firm's optimal wage and recruitment policy, when the dynamic labor supply to the firm is specified as a Poisson distributed flow of job-applicants, whose reservation wages are distributed in a fairly general way. Provided that the firm is not allowed to lower its wage level over time, it has recently been shown by the author that the optimal policy is to establish a constant wage level over future employment states. The paper explores the further properties of the optimal wage and its response to changes in the parameters of the decision problem

Status of young-of-the-year brown trout ( Salmo trutta fario ) in Swiss streams: factors influencing YOY trout recruitment

Abstract.: As part of the Swiss Fischnetz project (network for declining fish yields in Switzerland) studies were carried out to investigate the decline in catches of brown trout. Insufficient YOY (young-of-the-year) recruitment of brown trout due to different abiotic and/or biotic factors was hypothesized as a potential cause of this decline. Quantitative assessments of fish ecology parameters and habitat measurements were carried out at 97 river sites over a two-year period. The main objectives of this study were to document the occurrence and abundance of naturally reproduced YOY trout and to develop an understanding of environmental factors responsible for the observed YOY density. A general linear model (GLM) was used to analyse the influence of selected environmental abiotic and biotic parameters on YOY density. Successful recruitment of YOY trout was observed in all but three of the sites studied. Abundance was correlated with abiotic and biotic factors, such as river width, slope, altitude, substratum condition, and the occurrence of proliferative kidney disease (PKD). The results highlight the importance of small streams for natural YOY recruitment of brown trout and their function as a source of individuals for downstream river section

Fixed-Parameter Algorithms for Computing RAC Drawings of Graphs

In a right-angle crossing (RAC) drawing of a graph, each edge is represented as a polyline and edge crossings must occur at an angle of exactly $90^\circ$, where the number of bends on such polylines is typically restricted in some way. While structural and topological properties of RAC drawings have been the focus of extensive research, little was known about the boundaries of tractability for computing such drawings. In this paper, we initiate the study of RAC drawings from the viewpoint of parameterized complexity. In particular, we establish that computing a RAC drawing of an input graph $G$ with at most $b$ bends (or determining that none exists) is fixed-parameter tractable parameterized by either the feedback edge number of $G$, or $b$ plus the vertex cover number of $G$.Comment: Accepted at GD 202

The Replacement of the UV-Curve with a New Measure of Hiring Efficiency

In this paper we show that changes in the position of the UV-Curve do not unambiguously reflect changes in labour market adjustment ability. In fact, the UV-Curve is displaced not only when hiring efficiency changes but also when the volume of hiring changes. To identify changes in hiring efficiency, we should use the relation between either the duration of vacancies and the stock of unemployment or, alternatively, the duration of unemployment and the stock of vacancies. These measures are applied to Swedish data and produce interesting new evidence on the hiring efficiency of the labour market in Sweden

A case for reevaluation of Stalin's role in the Spanish Civil War

My thesis proposal was to reanalyze secondary sources on the Spanish Civil War, review primary sources, sort out conflicting theories, and document a case for Stalin's most probable role in that war. This thesis provides alternate perspectives for further scholarly consideration

Maritime Navigation: Characterizing Collaboration in a High-Speed Craft Navigation Activity

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