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Vem gör vad inom revisionsteam? / Who does what in the audit team?Bärlund, Sara, Prantner, Antonia January 2016 (has links)
Tidigare forskning/studier om en revisors bedömningfokuserar i stor utsträckning enbart på enskildarevisorer, trots att mycket av revisionen sker i team. Teorin som finns om teamarbete inom revisioninnehåller framförallt uppfattningar kring hur arbetetska fördelas och hur teamarbetet är tänkt att fungera, samt beskriver fyra traditionella roller inomrevisionsteam. Dock förekommer det få studier om vilka olika medlemmar som finns inom ett revisionsteam i praktiken och vad dessa medlemmar faktiskt gör. Studiens syfte är att beskriva vilka roller det finns inom revisionsteam och hur arbetsdelningen ser ut mellan teammedlemmarna. Studien är kvalitativ och har en induktiv ansats med deduktiva inslag. För att besvara syftet har semistrukturerade intervjuer genomförts med respondenter från olika revisionsbyråer samt material från olika revisionsbyråers hemsidor och jobbannonser inom revision har använts. Slutsats: Antal medlemmar och roller i ett revisionsteam påverkas av byrå-, uppdrags- och kontorsstorlek, erfarenhet hos enskilda teammedlemmar samt klient. Dessa faktorer påverkar också vad respektive roll gör. Inom ett revisionsteam finns det minst en påskrivande revisor och en revisorsassistent. De traditionella rollerna som omnämns i teorin förekommer också i praktiken, men ibland med andra benämningar och ansvarsområden. Revisorsassistenter utför den största delen avgranskningen, medan de överordnade revisorerna ansvarar mer för administrativt arbete såsom att planera revisionen, fördela ut arbete eller ansvara för klientrelaterade aktiviteter. / Problem: Previous research/studies that has been done onauditor’s judgments, focuses largely on individualauditors only, despite the fact that much of the auditis done in teams. The theory about teamwork inauditing includes above all perceptions of how thework is divided in the team and how teams aresupposed to work, it also describes four traditionalroles in auditing. However, there are few studiespublished about what different kinds of membersexist in practice within audit teams and what thesemembers actually do. Aim: The aim of the study is to describe which roles existswithin the audit team and how the job splitting isdone between teammembers. Method: It is a qualitative study that has an inductiveapproach but includes some deductive elements. Tobe able to answer the aim of the study, semistructuredinterviews were conducted withrespondents from different audit firms, as well asusing materials obtained from audit firms websites’and job advertising within the audit area. Conclusion: The number of members and roles in an audit team isaffected by assignment-, firm- and office size butalso by the experience of the individual member andthe client. These factors also affect what each roledoes. In an audit team there has to be at least oneengagement leader and one junior auditor. Thetraditional roles that is known in the theory are alsopresent in the empirical data, but sometimes withdifferent titles and different fields ofresponsibility.The junior auditors are the ones that dothe biggest part of the audit, while the superiorauditors are responsible for administrative work likeplaning, job splitting, or is responsible forclientrelated activities.
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Design of Water Splitting Devices via Molecular EngineeringLi, Fusheng January 2016 (has links)
Converting solar energyto fuels such as hydrogen by the reaction of water splitting is a promising solution for the future sustainable energy systems. The theme of this thesis is to design water splitting devices via molecular engineering; it concerns the studies of both electrochemical-driven and photo-electrochemical driven molecular functional devices for water splitting. The first chapter presents a general introduction about Solar Fuel Conversion. It concerns molecular water splitting catalysts, light harvesting materials and fabrication methods of water splitting devices. The second chapter describes an electrode by immobilizing a molecular water oxidation catalyston carbon nanotubes through the hydrophobic interaction. This fabrication method is corresponding to the question: “How to employ catalysts in functional devices without affecting their performances?” In the third chapter, molecular water oxidation catalysts were successfully immobilized on glassy carbon electrode surface via electrochemical polymerization method. The O-O bond formation pathways of catalysts on electrode surfaces were studied. This kinetic studyis corresponding to the question: “How to get kinetic information of RDS whena catalyst is immobilized on the electrode surface?” Chapter four explores molecular water oxidation catalysts immobilized on dye-sensitized TiO2 electrodeand Fe2O3 semiconductor electrode via different fabrication methods. The reasons of photocurrent decay are discussed and two potential solutions are provided. These studies are corresponding to the question: “How to improvethe stability of photo-electrodes?” Finally, in the last chapter, two novel Pt-free Z-schemed molecular photo-electrochemical cells with both photoactive cathode and photoactive anode for visible light driven water splitting driven were demonstrated. These studies are corresponding to the question: “How to utilizethe concept of Z-schemein photosynthesis to fabricate Pt-free molecular based PEC cells? / <p>QC 20160129</p>
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Stream splitting in support of intrusion detectionJudd, John David 06 1900 (has links)
Approved for public release, distribution is unlimited / One of the most significant challenges with modern intrusion detection systems is the high rate of false alarms that they generate. In order to lower this rate, we propose to reduce the amount of traffic sent a given intrusion detection system via a filtering process termed stream splitting. Each packet arriving at the system is treated as belonging to a connection. Each connection is then assigned to a network stream. A network stream can then be sent to an analysis engine tailored specifically for that type of data. To demonstrate a stream-splitting capability, both an extendable multi-threaded architecture and prototype were developed. This system was tested to ensure the ability to capture traffic and found to be able to do so with minimal loss at network speeds up to 20 Mb/s, comparable to several open-source analysis programs. The stream splitter was also shown to be able to correctly implement a traffic separation scheme. / Ensign, United States Navy
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Theoretical investigation of the water splitting mechanism on transition metal oxide catalystsHewa Dewage, Amendra Fernando January 1900 (has links)
Doctor of Philosophy / Department of Chemistry / Christine M. Aikens / Water oxidation can be considered as the ‘holy grail’ of renewable energy research, where water is split into constituent molecular hydrogen and oxygen. Hydrogen is a very efficient energy source that is both clean and sustainable. The byproduct of hydrogen combustion is water, which in turn can be reused as the source for hydrogen generation. Natural water splitting is observed during photosynthesis in the oxygen-evolving complex of photosystem II, which consists of a CaMn₄O₄ cubane core. Herein, we report in silico approaches to understand bottom up catalytic design of model transition metal oxide complexes for water splitting. We have employed density functional theory to investigate model ligand-free architectures of cobalt and manganese oxide dimer (Mn₂(μ-OH)(μ-O)(H₂O)₃(OH)₅, Mn₂(μ-OH)₂(H₂O)₄(OH)₄, Mn₂(μ-OH)₂(H₂O)₂(OH)₂(O(CH)₃O)₂, Co₂(μ-OH)₂(H₂O)₄(OH)₄ and cubane (Co₄O₄(H₂O)₈(OH)₄, Mn₄O₄(H₂O)[subscript]x(OH)[subscript]y x = 4-8, y = 8-4) complexes.
The thermodynamically lowest energy pathway on the cobalt dimer catalyst proceeds through a nucleophilic attack of a solvent water molecule to a Co(V)-O radical moiety whereas the pathway on the cubane catalyst involves a geminal coupling of a Co(V)-O radical oxo group with bridging oxo sites. The lowest energy pathway for the fully saturated Mn₂O₄•6H₂O (Mn₂(μ-OH)(μ-O)(H₂O)₃(OH)₅) and Mn₂O₃•7H₂O (Mn₂(μ-OH)₂(H₂O)₄(OH)₄) complexes occur through a nucleophilic attack of a solvent water molecule to Mn(IV½)O and Mn(V)O oxo moieties respectively. Out of all the oxidation state configurations studied for the manganese cubane, we observed that Mn₄(IV IV IV IV), Mn₄(III IV IV IV), and Mn₄(III III IV V) configurations are thermodynamically viable for water oxidation. All three of these reaction pathways proceed via nucleophilic attack of solvent water molecule to the manganese oxo species. The highest thermodynamic energy step in manganese dimer and cubane complexes corresponds to the formation of the manganese oxo species, which is a significant feature that reoccurred in all these reaction pathways. We have also employed multireference and multiconfigurational calculations to investigate the Mn₂(μ-OH)₂(H₂O)₂(OH)₂(O(CH)₃O)₂ system. The presence of Mn(IV)O[superscript]• radical moieties has been observed in this catalytic pathway. These simplest models of cobalt and manganese with water-derived ligands are essential to understand microscopic properties that can be used as descriptors in designing future catalysts.
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Environmental stability study of holographic solar spectrum splitting materialsChrysler, Benjamin D., Ayala Pelaez, Silvana, Wu, Yuechen, Vorndran, Shelby D., Kostuk, Raymond K. 23 September 2016 (has links)
In this study the impact of outdoor temperature variations and solar illumination exposure on spectral filter material and holographic optical elements is examined. Although holographic components have been shown to be useful for solar spectrum splitting designs, relatively little quantitative data exist to demonstrate the extent to which these materials can withstand outdoor conditions. As researchers seek to investigate practical spectrum splitting designs, the environmental stability of holographic materials should be considered as an important factor. In the experiment presented, two holographic materials, Covestro Bayfol HX photopolymer and dichromated gelatin, and 3M reflective polymer filter materials are exposed to outdoor conditions for a period of several months. The environmental effect on absorption, spectral and angular bandwidth, peak efficiency, and Bragg matching conditions for the holograms are examined. Spectral bandwidth and transmittance of the 3M reflective filter material are also monitored. Holographic gratings are recorded, measured, and mounted on glass substrates and then sealed with a glass cover plate. The test samples are then mounted on a photovoltaic panel to simulate realistic temperature conditions and placed at an outdoor test facility in Tucson, Arizona. A duplicate set of holograms and 3M filter material is stored as a control group and periodically compared over the test period.
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Three junction holographic micro-scale PV systemWu, Yuechen, Vorndran, Shelby, Ayala Pelaez, Silvana, Kostuk, Raymond K. 23 September 2016 (has links)
In this work a spectrum splitting micro-scale concentrating PV system is evaluated to increase the conversion efficiency of flat panel PV systems. In this approach, the dispersed spectrum splitting concentration systems is scaled down to a small size and structured in an array. The spectrum splitting configuration allows the use of separate single bandgap PV cells that increase spectral overlap with the incident solar spectrum. This results in an overall increase in the spectral conversion efficiency of the resulting system. In addition other benefits of the micro-scale PV system are retained such reduced PV cell material requirements, more versatile interconnect configurations, and lower heat rejection requirements that can lead to a lower cost system. The system proposed in this work consists of two cascaded off-axis holograms in combination with a micro lens array, and three types of PV cells. An aspherical lens design is made to minimize the dispersion so that higher concentration ratios can be achieved for a three-junction system. An analysis methodology is also developed to determine the optical efficiency of the resulting system, the characteristics of the dispersed spectrum, and the overall system conversion efficiency for a combination of three types of PV cells.
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Optimizing Optimization: Scalable Convex Programming with Proximal OperatorsWytock, Matt 01 March 2016 (has links)
Convex optimization has developed a wide variety of useful tools critical to many applications in machine learning. However, unlike linear and quadratic programming, general convex solvers have not yet reached sufficient maturity to fully decouple the convex programming model from the numerical algorithms required for implementation. Especially as datasets grow in size, there is a significant gap in speed and scalability between general solvers and specialized algorithms. This thesis addresses this gap with a new model for convex programming based on an intermediate representation of convex problems as a sum of functions with efficient proximal operators. This representation serves two purposes: 1) many problems can be expressed in terms of functions with simple proximal operators, and 2) the proximal operator form serves as a general interface to any specialized algorithm that can incorporate additional `2-regularization. On a single CPU core, numerical results demonstrate that the prox-affine form results in significantly faster algorithms than existing general solvers based on conic forms. In addition, splitting problems into separable sums is attractive from the perspective of distributing solver work amongst multiple cores and machines. We apply large-scale convex programming to several problems arising from building the next-generation, information-enabled electrical grid. In these problems (as is common in many domains) large, high-dimensional datasets present opportunities for novel data-driven solutions. We present approaches based on convex models for several problems: probabilistic forecasting of electricity generation and demand, preventing failures in microgrids and source separation for whole-home energy disaggregation.
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Kalkulační systém a jeho využití v řízení konkrétní firmy / A Costing System and its Utilization in Management in a particular FirmPykalová, Michala January 2008 (has links)
The aim of the thesis was to analyse the costing system in Kasalova pila, s. r. o., to assess the complexity of the performed calculations to determine if the calculations are updated regularly. Further, it was examined the influence of costing system for management of the company. The thesis is divided into two main parts, theoretical and practical part. The theoretical part describes the main concepts of costing, cost classification methods, costing system and its components and structure. In the introduction of the practical part of this thesis is briefly described the company Kasalova pila, s. r. o. In the following chapters is described the costing model used by the example of a particular product. In conclusion of the thesis is reviewed the whole costing system and proposed several recommendations.
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Synthesis and Applications of Vertically Aligned Silicon Nanowire Arrays for Solar Energy ConversionYuan, Guangbi January 2012 (has links)
Thesis advisor: Dunwei Wang / Solar energy, the most abundant and free renewable energy, holds great promise for humanity's sustainable development. How to efficiently and inexpensively capture, covert solar energy and store it for off peak usages constitutes a grand challenge for the scientific community. Photovoltaic devices are promising candidates but are too costly to be implemented in large scales. On a fundamental level, this is due to the dilemma that the length scales of the optical pathways and electrical pathways often do not match within the photovoltaic device materials. Consider traditional Si solar cell as an example, effective light absorption requires up to hundreds of microns material while the photogenerated charge carries can only diffuse less than a few microns or even shorter before recombination. Such a problem may be solved by using Si nanowires (SiNWs) because vertically aligned nanowires can orthogonalize the light absorption and charge carrier collection pathways, thereby enabling the use of low-cost materials for practically appealing solar energy conversion devices. The objective of this thesis work is to explore low-cost synthesis of vertically aligned SiNW arrays and study their performance in both solar energy conversion and storage devices. We developed a method to synthesize vertically aligned SiNW arrays in a hot-wall chemical vapor deposition system with tunable length, doping level, and diameter for systematical studies. Empowered by the synthetic control, various types of vertical SiNW arrays were characterized by both steady-state (photoelectrochemical measurement) and transient (electrochemical impedance spectroscopy) techniques in a photoelectrochemical cell platform. Additionally, SiNWs were demonstrated to be a promising candidate for photoelectrochemical aromatic ketone reduction and CO₂ fixation. The reactions studied in this thesis are in close resemblance to natural photosynthesis and the resulted product molecules are precursors to nonsteroidal anti-inflammatory drugs, ibuprofen and naproxen. Lastly, vertical transparent conductive oxide nanotubes were prepared from vertical SiNW array templates. Ultrathin hematite (Fe₂O₃) film was coated on the nanotube scaffold by atomic layer deposition to form a heteronanostructure photoelectrode for efficient solar water oxidation. Our results highlight the potential of vertically aligned SiNW arrays in solar cell, solar water splitting and artificial photosynthesis applications. / Thesis (PhD) — Boston College, 2012. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
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Atomic Layer Deposition Synthesis and Photoelectrochemical Charge Behavior in Tungsten, Iron, and Titanium Oxide HeterostructuresSheehan, Stafford Wheeler January 2011 (has links)
Thesis advisor: Dunwei Wang / This thesis explores new approaches to synthesizing and understanding photoanodes for water splitting. By tuning materials' mophology on the nanoscale, their ability to absorb light energy and efficiently convert it in to chemical energy is improved. This is evident by an increase in photocatalytic efficiency and can be demonstrated with visible light sensitive catalysts. Production of these materials involved the development of alternative synthesis routes for traditional water splitting catalysts. Our hypothesis is further supported by probing charge dynamics using microwave reflectivity measurements, which show that the lifetime of charges in these new nanostructures is optimized. / Thesis (BS) — Boston College, 2011. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Chemistry Honors Program. / Discipline: Chemistry.
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