Laser wakefield and direct acceleration in the plasma bubble regime

Laser wakefield acceleration (LWFA) and direct laser acceleration (DLA) are two different kinds of laser plasma electron acceleration mechanisms. LWFA relies on the laser-driven plasma wave to accelerate electrons. The interaction of ultra-short ultra-intensive laser pulses with underdense plasma leads the LWFA into a highly nonlinear regime (“plasma bubble regime”) that attracts particular interest nowadays. DLA accelerates electrons by laser electromagnetic wave in the ion channel or the plasma bubble through the Betatron resonance. This dissertation presents a hybrid laser plasma electron acceleration mechanism. We investigate its features through particle-in-cell (PIC) simulations and the single particle model. The hybrid laser plasma electron acceleration is the merging concept between the LWFA and the DLA, so called laser wakefield and direct acceleration (LWDA). The requirements of the initial conditions of the electron to undergo the LWDA are determined. The electron must have a large initial transverse energy. Two electron injection mechanisms that are suitable for the LWDA, density bump injection and ionization induced injection, are studied in detail. The features of electron beam phase space and electron dynamics are explored. Electron beam phase space appears several unique features such as spatially separated two groups, the correlation between the transverse energy and the relativistic factor and the double-peak spectrum. Electrons are synergistically accelerated by the wakefield as well as by the laser electromagnetic field in the laser-driven plasma bubble. LWDA are also investigated in the moderate power regime (10 TW) in regarding the effects of laser color and polarization. It is found that the frequency upshift laser pulse has better performance on avoiding time-jitter of electron energy spectra, electron final energy and electron charge yield. Some basic characters that related to the LWDA such as the effects of the subluminal laser wave, the effects of the longitudinal accelerating field, the electron beam emittance, the electron charge yield and potentially applications as radiation source are discussed.Physic

POSSIBILITIES OF INITIAL ESTIMATION AND FURTHER VALIDATION OF INSIDE CONTROL RISK

The approach option of the theme of this essay had in mind the distinguished importance of the objective of inside control regarding the segmentation with maximum exigency of the risks which can disadvantageously influence the fulfillment of the entity objectives. We considered essential the use of adequate procedures regarding the estimation and documentary validation of inside control risk. Regarding the initial estimation we analyzed the phases that are justified to be followed (four) and the proper steps which are followed (ten), starting with the assessment of audit objectives on types of operations and ending with reporting to the competent institutions. Regarding initial risk validation we examined the subsequent circumstances of this operation which are influencing the forecasted risk level, like: adjourning of control mechanisms applications, the apparition of new legal procedures, the alterations of the entity’s politics, etc.critical; inside control, initial risk estimation, subsequent risk validation, risk estimation procedure.

EARNED VALUE MANAGEMENT.CASE STUDY USING MICROSOFT PROJECT

A formalism and a corresponding notation for earned value analysis are presented. With compact, consistent, mnemonic notation, earned value calculations become more transparent and flexible, leading to insights about standard quantities and advances through new measures. As an example of the notation’s utility, it is used to generate a modified earned value approach that weights quantities according to their position in a project’s timeline.earned value, managing projects, progress, cost, cash flow management

THE ROLE OF DATA ARCHITECTURE AS A PART OF ENTERPRISE ARCHITECTURE

In the early days of computing, technology simply automated manual processes with greater efficiency. The new organizational context provides input into the data architecture and is the primary tool for the management and sharing of enterprise data. It enables architects, data modelers, and stakeholders to identify, classify, and analyze information requirements across the enterprise, allowing the right priorities for data sharing initiatives. Data architecture states how data are persisted, managed, and utilized within an organization. Data architecture is made up of the structure of all corporate data and its relationships to itself and external systems. In far too many situations, the business community has to enlist the assistance of IT to retrieve information due to the community's inconsistency, lack of intuitiveness, or other factors. The goal of any architecture should illustrate how the components of the architecture will fit together and how the system will adapt and evolve over time.data architecture, enterprise architecture, business process planning,databases, business objects.

Minimally supervised induction of morphology through bitexts

textA knowledge of morphology can be useful for many natural language processing systems. Thus, much effort has been expended in developing accurate computational tools for morphology that lemmatize, segment and generate new forms. The most powerful and accurate of these have been manually encoded, such endeavors being without exception expensive and time-consuming. There have been consequently many attempts to reduce this cost in the development of morphological systems through the development of unsupervised or minimally supervised algorithms and learning methods for acquisition of morphology. These efforts have yet to produce a tool that approaches the performance of manually encoded systems. Here, I present a strategy for dealing with morphological clustering and segmentation in a minimally supervised manner but one that will be more linguistically informed than previous unsupervised approaches. That is, this study will attempt to induce clusters of words from an unannotated text that are inflectional variants of each other. Then a set of inflectional suffixes by part-of-speech will be induced from these clusters. This level of detail is made possible by a method known as alignment and transfer (AT), among other names, an approach that uses aligned bitexts to transfer linguistic resources developed for one language–the source language–to another language–the target. This approach has a further advantage in that it allows a reduction in the amount of training data without a significant degradation in performance making it useful in applications targeted at data collected from endangered languages. In the current study, however, I use English as the source and German as the target for ease of evaluation and for certain typlogical properties of German. The two main tasks, that of clustering and segmentation, are approached as sequential tasks with the clustering informing the segmentation to allow for greater accuracy in morphological analysis. While the performance of these methods does not exceed the current roster of unsupervised or minimally supervised approaches to morphology acquisition, it attempts to integrate more learning methods than previous studies. Furthermore, it attempts to learn inflectional morphology as opposed to derivational morphology, which is a crucial distinction in linguistics.Linguistic