American policy makers primarily embrace a deterrent-based policing agenda to curb illicit drug trafficking and use that relies on the principles of the economic price elasticity of demand (Boynum & Reuter, 2005). This counter-drug platform includes three fundamental programs: arresting offenders, seizing illicit drugs, and eradicating horticultural sources of illicit drugs (U.S. DEA, 2015). One of the main goals of these programs is to deter illegal trafficking and use by increasing the price of illicit substances so they are no longer attractive to consumers. The United States has weathered various drug use epidemics during its history, and currently it is facing a heroin and opioid epidemic (Dean, 2017). The present multi-dimensional study is guided by three broad goals: to assess the dynamics of illicit drug pricing and the economic price elasticity of demand perspective; to evaluate whether drug trafficking organizations respond to theoretically deterrence based counter-drug law enforcement efforts; and to assess why law enforcement activities are (or are not) effective in controlling illegal drug markets. To accomplish these three broad goals, four separate yet linked focal points comprised of quantitative, qualitative, and mixed-methods evaluations of official data are examined. The findings in the study call into question the current American counter-drug law enforcement agenda being used to address the ongoing heroin epidemic. Furthermore, the results shine light on various shortcomings in overall U.S. counter-drug policy. Finally, the study calls for a new approach to address illicit drug trafficking and use in the U.S.

The solutions to certain elliptic boundary value problems have singularities with a typical structure near polyhedral corners. This structure can be exploited to devise an eigenvalue problem whose solution can be used to quantify the singularities of the given boundary value problem. It is necessary to parametrize a ball centered at the corner. There are different possibilities for a suitable parametrization; from the numerical point of view, spherical coordinates are not necessarily the best choice. This is why we do not specify a parametrization in this paper but present all results in a rather general form. We derive the eigenvalue problems that are associated with the Laplace and the linear elasticity problems and show interesting spectral properties. Finally, we discuss the necessity of widely accepted symmetry properties of the elasticity tensor. We show in an example that some of these properties are not only dispensable, but even invalid, although claimed in many standard books on linear elasticity.

The constant gamma in the strengthened Cauchy-Bunyakowskii-Schwarz inequality is a basic tool for constructing of two-level and multilevel preconditioning matrices. Therefore many authors consider estimates or computations of this quantity. In this paper the bilinear form arising from 3D linear elasticity problems is considered on a polyhedron. The cosine of the abstract angle between multilevel finite element subspaces is computed by a spectral analysis of a general eigenvalue problem. Octasection and bisection approaches are used for refining the triangulations. Tetrahedron, pentahedron and hexahedron meshes are considered. The dependence of the constant $\gamma$ on the Poisson ratio is presented graphically.

Thesis (M.Sc. Agriculture (Agricultural Economics) -- University of Limpopo, 2019 / Studies have indicated that sorghum hectares in South Africa have been decreasing over the past decades. This has resulted in a huge importation of the grain sorghum by the country. This study was undertaken due to sorghum production variability in South Africa. The objectives of this study were to estimate elasticity of sorghum production to changes in price and non-price factors, as well as estimating the short-run and long-run sorghum price elasticity. The study used time series data spanning from 1998 to 2016. This data was obtained from the abstracts of agricultural statistics and verified by South African Grain Information Services. Variance Error Correction Model (VECM) was employed to address both objectives. A number of diagnostic tests were performed to ensure that the study does not produce spurious regression results. This study estimated sorghum supply elasticity using two dependent variables being the area and yield response functions as model one and two respectively. The results have shown that area response function was found to be a robust model as most of the variables were significant, responsive and elastic. Maize price as a competing crop of sorghum negatively influenced the area allocation; however, the remaining variables positively influenced the area allocation in the long-run. In this model, all variables were statistically significant at 10% and 1% in the short and long-run respectively. In the yield function, most of the variables were insignificant, not responsive and inelastic, therefore, this model was found not to be robust and hence not adopted. Thus, it was concluded that sorghum output in South Africa is less sensitive to changes in price and nonprice factors. The findings further indicated that error correction term for area was -1.55 and -1.30 for yield response function. This indicated that the two models were able to revert to equilibrium. Therefore, it was concluded that the area response function was more robust, while the yield response function was not. Furthermore, it was concluded that sorghum production was more responsive to area allocation than yield function. Based on the findings, the study recommends that amongst other methods to enhance sorghum output, producers could use improved varieties or hybrids, as this action would result in allocation of more land to sorghum production, following price change.

i Abstract In this work, we describe a novel methodology to analyse the price elasticity of demand. This method combines an artificial neural network that serves as the model of the behaviour of the customers and a subsequent simulation based on this model. We present the validation of our approach using a real-world dataset obtained from an e-commerce retailer and demonstrate its advantages, notably the ability to estimate the elasticity in distinct price points and the inclusion of the complete pricing situations (not only product's own price). JEL Classification C45, C44, C15, D12 Keywords price elasticity of demand, artificial neural net- work, agent-based model Title A simulation based analysis of price elasticity of demand Author's e-mail Supervisor's e-mail

Today’s bridge design work in many cases demands a trustworthy dynamic analysis instead of using the traditional dynamic amplification factors. In this thesis a reliable 3D Bernoulli-Euler beam finite element model of the New Årsta Railway Bridge was prepared for thorough dynamic analysis using in situ bridge monitoring for correlation. The bridge is of the concrete box girder type with a heavily reinforced and prestressed bridge deck. The monitoring system was designed for long term monitoring with strain transducers embedded in the concrete and accelerometers mounted inside the edge beams and at the lower edge of the track slab. The global finite element model used the exact bridge geometry but was simplified regarding prestressing cables and the two railway tracks. The prestressing cables and the tracks were consequently not included and an equivalent pure concrete model was identified. A static macadam train load was eccentrically placed on one of the bridge’s two tracks. By using Vlasov’s torsional theory and thereby including constrained warping a realistic modulus of elasticity for the concrete without prestressing cables and stiffness contribution from the railway tracks was found. This was allowed by comparing measured strain from strain transducers with the linear elastic finite element model’s axial stresses. Mainly three monitoring bridge sections were used, each of which was modelled with plane strain finite elements subjected to sectional forces/moments from a static macadam train load and a separately calculated torsional curvature. From the identified modulus of elasticity the global finite element model was updated for Poisson’s ratio and material density (mass) to correspond with natural frequencies from the performed signal analysis of accelerometer signals. The influence of warping on the natural frequencies of the global finite element model was assumed small and the bridge’s torsional behaviour was modelled to follow Saint-Venant’s torsional theory. A first preliminary estimation of modal damping ratios was included. The results indicated that natural frequencies were in accordance between modelling and signal analysis results, especially concerning high energy modes. Estimated damping ratios for the first vibration modes far exceeded the lower limit value specified in bridge design codes and railway bridge dynamic analysis recommendations. / QC 20101124

No description available.

High Speed Lines (HSL) in rail passenger services are regarded as one of the most significant projects in many countries comparing to other projects in the transportation area. According to the EU (European Council Directive 96/48/EC,2004) , high-speed lines are either new-built lines for speeds of 250km/h or greater, or in some cases upgraded traditional lines. At the beginning of 2008, there were 10,000 km of new HSL lines in operation, and by taking into account the upgraded conventional lines, in total, there were 20,000 km line in the world. The network is growing fast because of the demand for short travelling time and comfort isincreasing rapidly. Since HSL projects require a lot of capital, it is getting more important for governments and companies to estimate and to calculate the total costs and benefits of building, maintaining, and operating of HSL so that they can decide better and more reliable in choosing between projects. There are many parameters which affect the total costs and benefits of an HSL. The most important parameter is dimensional speed which has a great influence on other parameters. For example, tunnels need larger cross section for higher speed which increases construction costs. More important, higher speed also influences the number of passengers attracted from other modes of transport. Due to a large number of speed-dependant parameters, it is not a simple task to estimate an optimal dimensional speed by calculating the costs and benefits of an HSL manually. It is also difficult to do analysis for different speeds, as speed changes many other relevant parameters. As a matter of fact, there is a need for a computational model to calculate the cost-benefit for different speeds. Based on the computational model, it is possible to define different scenarios and compare them to each other to see what the potentially optimal speed would be for a new HSL project. Besides the optimal speed, it is also possible to analyze and find effects of two other important parameters, fare and frequency, by cost-benefit analysis (CBA). The probability model used in the calculation is based on an elasticity model, and input parameters are subject to flexibility to calibrate the model appropriately. Optimal high-speed line (OHSL) tool is developed to make the model accessible for the users.

FPGAs are commonly used in cloud computing due to their ability  to be  programmed  as a processor that serves a specific purpose; hence, achieving high performance at low power. On the other hand, FPGAs have a lot of resources available, which are wasted if they host a single application or serve a single user’s request. Partially Reconfiguration technology enables FPGAs to divide their resources into different regions and then dynamically reprogram those regions with various applications during runtime. Therefore, they are considered as a good solution to eliminate the underutilization resource problem. Nevertheless, the sizes of these regions are static; they cannot be increased or decreased once they are defined. Thereby, it leads to the underutilization of reconfigurable region resources. This thesis addresses this problem, i.e., how to dynamically increase/decrease partially reconfigurable FPGA resources matching an application’s needs. Our solution enables expanding and contracting the FPGA resources allocated to an application by 1) application acceleration requirements expressed in multiple smaller modules which are configured into multiple reconfigurable regions assigned to the application dynamically  and 2) providing a low - area - overhead, configurable, and isolated communication mechanism by adjusting crossbar interconnect and WISHBONE interface among those multiple reconfigurable regions. / FPGA - kretsar har en förmåga  att programmeras som processorer med ett specifikt syfte vilket gör att de ofta används i molnlösningar. Det tager hög prestanda med låg effektförbrukning. Å andra sidan disponerar FPGA - kretsar över stora resurser, vilka är bortkastade om de enbart används av en applikation eller endast på en användares förfrågan. Partiellt omkonfigurerbara teknologier tillåter FPGA - kretsar att fördela resurser mellan olika regioner, och sen dynamiskt omprogrammera regioner med olika applikationer vid körning. Därför betraktas partiellt omkonfigurerbara teknologier som en bra lösning för att minimera underutnyttjande av resurser. Storleken på regionerna är statiska och kan inte ändras när de väl definierats, vilket leder till underutnyttjande av de omkonfigurerbara regionernas resurser. Denna uppsats angriper problemet med dynamisk allokering av partiellt omkonfigurerbara FPGA - resurser utifrån applikationens behov. Vår lösning möjliggör ökning och minskning av FPGA - resurser allokerade till en applikation genom 1) accelerering av applikationen genom att applikationen tilldelas flera mindre moduler konfigurerade till dynamiskt omkonfigurerbara regioner, och 2) tillhanda hållande av en effektiv konfigurerbar och isolerad kommunikationsmekanism, genom justering av crossbar - sammankoppling en  och  WISHBONE - gränssnittet hos de omkonfigurerbara regionerna.

When estimating the influence income per capita exerts on health care expenditure, the research in the field offers mixed results. Studies employ different data, estimation techniques and models, which brings about the question whether these differences in research design play any part in explaining the heterogeneity of reported outcomes. By employing meta-regression analysis, the present paper analyzes 220 estimates of health spending income elasticity collected from 54 studies and finds that publication bias is of marginal concern for the literature. The model specification choices, more exactly whether a study accounts for institutional factors and advancements in medical technology, have a negative effect on reported outcomes. Moreover, the "economic research cycle hypothesis" finds support in our analysis. Lastly, the research finds that the true income elasticity of health spending is situated around unity level, which makes health care neither a luxury, nor a necessity. Keywords: meta-regression analysis, aggregate health expenditure, income elasticity 1