A deeper understanding of Cu(In,Ga)Se2 (CIGS) solar cells is important for the further improvement of these devices. This thesis is focused on the use of electrical modelling as a tool for pursuing this aim. Finished devices and individual layers are characterized and the acquired data are used as input in the simulations. Band gap gradients are accounted for when modelling the devices. The thesis is divided into two main parts. One part that treats the influence of cadmium free buffer layers, mainly atomic layer deposited (Zn,Mg)O, on devices and another part in which the result of CIGS absorber layer modifications is studied. Recombination analysis indicates that interface recombination is limitting the open circuit voltage (Voc) in cells with ZnO buffer layers. This recombination path becomes less important when magnesium is introduced into the ZnO giving a positive conduction band offset (CBO) towards the CIGS absorber layer. Light induced persistent photoconductivity (PPC) is demonstrated in (Zn,Mg)O thin films. Device modelling shows that the measured PPC, coupled with a high density of acceptors in the buffer-absorber interface region, can explain light induced metastable efficiency improvement in CIGS solar cells with (Zn,Mg)O buffer layers. It is shown that a thin indium rich layer closest to the buffer does not give any significant impact on the performance of devices dominated by recombination in the CIGS layer. In our cells with CdS buffer the diffusion length in the CIGS layer is the main limitting factor. A thinner CIGS layer improves Voc by reducing recombination. However, for thin enough absorber layers Voc deteriorates due to recombination at the back contact. Interface recombination is a problem in thin devices with Zn(O,S) buffer layers. This recombination path is overshadowed in cells of standard thickness by recombination in the CIGS bulk. Thin cells with Zn(O,S) buffer layers have a higher efficiency than CdS cells with the same absorber thickness.

The term criminal career is used to describe the course or progress of criminal activity: its onset, duration, termination, severity, and change in severity. Such a term has important implications, given that significant criminal justice, social, and health policies such as crime control, parole, and correctional treatment and management are predicated on achieving the reduction of criminal careers of serious, repeat offenders. Despite its conceptual simplicity, however, criminal career is often treated as having no depth or scope, for example, merely as the number of crimes or length of prison sentence. These indices often give no or little consideration to criminal career parameters and tend to account for only a small portion of the construct of criminal careers. Ideally, a simple metric to measure the onset, duration, termination, severity, and change in severity of a pattern of criminal activities is needed to facilitate the description and measurement of criminal careers of offenders. <p>The Criminal Career Profile (CCP), which uses commonly available criminological information and requires minimal professional skills to execute, can be considered a simple and precise measure of criminal careers. The CCP is a chronological representation on a Cartesian plane of the time in years an offender has spent in prison (y-axis) plotted against the time in years spent out of prison (x-axis) of all incarcerations and time spent in the community. Given that the CCP is a step function, a regression line can be generated. Serious crimes are generally given longer sentences, and more time in than out of prison would generate a steeper regression line. Shallower regression lines result from less time in than out of prison. As such, the CCP regression line can be considered an indication of the seriousness of offending, and the slope or angle of the regression line can be considered a quantitative index of criminal career severity. Larger slopes or angles (used in this Program of Research) suggest more serious criminal careers. Conversely, smaller slopes or angles suggest less serous criminal careers. Taken altogether, the CCP can provide a quantitative measure of criminal careers: its onset (age at first conviction, which is plotted as the first point on a CCP graph), duration (total time in and out of prison since onset), severity (CCP slope/angle), change in severity (change in CCP slope/angle), and termination (end point or when the CCP slope or angle becomes smaller and closer to 0).<p>This Program of Research was done to assess the CCPs validity and utility in measuring offenders criminal career. More specifically, the investigation focused on the seriousness of criminal careers. A number of criteria were used to validate the CCP angles ability to measure criminal career severity. In Study 1, psychopaths and violent recidivists showed a significantly larger CCP angle than nonpsychopaths and violent nonrecidivists, respectively. Finer groupings based on risk (high, medium, and low), a number of risk measures (Psychopathy Checklist Revised, Violence Risk Scale, and Violence Risk Scale Sexual Offender Version), and different types of offenders (i.e. violent, nonviolent, sexual, Dangerous Offenders) were used in Study 2. Two consistent findings across different groups of offenders in Study 2 were CCP angles significantly varied as a function of risk group and correlated with risk ratings. The pattern of results was that larger CCP angles tended to be associated with worse risk groups. In Study 3, both treated offenders and treatment dropouts showed a reduction in CCP angles from pre- to post-treatment. A nonsignificant interaction of group by treatment, however, suggests that post-treatment changes could not be attributed to treatment. Finally, Study 4 showed that CCP angles change with age. Taken altogether, the results of the four studies provided converging evidence for the validity of the CCP as a measure of criminal careers and the CCP angle as a measure of criminal career severity.

The term criminal career is used to describe the course or progress of criminal activity: its onset, duration, termination, severity, and change in severity. Such a term has important implications, given that significant criminal justice, social, and health policies such as crime control, parole, and correctional treatment and management are predicated on achieving the reduction of criminal careers of serious, repeat offenders. Despite its conceptual simplicity, however, criminal career is often treated as having no depth or scope, for example, merely as the number of crimes or length of prison sentence. These indices often give no or little consideration to criminal career parameters and tend to account for only a small portion of the construct of criminal careers. Ideally, a simple metric to measure the onset, duration, termination, severity, and change in severity of a pattern of criminal activities is needed to facilitate the description and measurement of criminal careers of offenders. <p>The Criminal Career Profile (CCP), which uses commonly available criminological information and requires minimal professional skills to execute, can be considered a simple and precise measure of criminal careers. The CCP is a chronological representation on a Cartesian plane of the time in years an offender has spent in prison (y-axis) plotted against the time in years spent out of prison (x-axis) of all incarcerations and time spent in the community. Given that the CCP is a step function, a regression line can be generated. Serious crimes are generally given longer sentences, and more time in than out of prison would generate a steeper regression line. Shallower regression lines result from less time in than out of prison. As such, the CCP regression line can be considered an indication of the seriousness of offending, and the slope or angle of the regression line can be considered a quantitative index of criminal career severity. Larger slopes or angles (used in this Program of Research) suggest more serious criminal careers. Conversely, smaller slopes or angles suggest less serous criminal careers. Taken altogether, the CCP can provide a quantitative measure of criminal careers: its onset (age at first conviction, which is plotted as the first point on a CCP graph), duration (total time in and out of prison since onset), severity (CCP slope/angle), change in severity (change in CCP slope/angle), and termination (end point or when the CCP slope or angle becomes smaller and closer to 0).<p>This Program of Research was done to assess the CCPs validity and utility in measuring offenders criminal career. More specifically, the investigation focused on the seriousness of criminal careers. A number of criteria were used to validate the CCP angles ability to measure criminal career severity. In Study 1, psychopaths and violent recidivists showed a significantly larger CCP angle than nonpsychopaths and violent nonrecidivists, respectively. Finer groupings based on risk (high, medium, and low), a number of risk measures (Psychopathy Checklist Revised, Violence Risk Scale, and Violence Risk Scale Sexual Offender Version), and different types of offenders (i.e. violent, nonviolent, sexual, Dangerous Offenders) were used in Study 2. Two consistent findings across different groups of offenders in Study 2 were CCP angles significantly varied as a function of risk group and correlated with risk ratings. The pattern of results was that larger CCP angles tended to be associated with worse risk groups. In Study 3, both treated offenders and treatment dropouts showed a reduction in CCP angles from pre- to post-treatment. A nonsignificant interaction of group by treatment, however, suggests that post-treatment changes could not be attributed to treatment. Finally, Study 4 showed that CCP angles change with age. Taken altogether, the results of the four studies provided converging evidence for the validity of the CCP as a measure of criminal careers and the CCP angle as a measure of criminal career severity.

In this study, the Persistent Organic Pollutants (POPs) specifically / 17 Organochlorine Pesticides (OCPs) and 19 Polycyclic Aromatic Hydrocarbons (PAHs) were evaluated in the sediment samples of Balikesir (Ikizcetepeler) Dam Lake. Sixteen sampling points were chosen for determination of concentrations of OCPs and PAHs After ultrasonic bath extraction of the sediment samples GC-MS was used as analytical tool. Extraction efficiencies changes from 63.8 to 87.4% depending on the type of the POPs. Average OCP concentration was found in the range of 3.33-379 &micro / g/kg a, average PAH concentration was found in the range of 3.28-32.9 &micro / g/kg. Pollution maps regarding OCP and PAH distributions were drawn and the correlation between these two pollutant types was investigated. The quality control (QC) and quality assurance tests were applied by the analysis of standard reference materials (SRMs), surrogate standards and analysis replicates.

In a variety of text document editing and processing applications, it is necessary to keep track of the revision history of text documents by recording changes and the metadata of those changes (e.g., user names and modification timestamps). The recent Web 2.0 document editing and processing applications, such as real-time collaborative note taking and wikis, require fine-grained shared access to collaborative text documents as well as efficient retrieval of metadata associated with different parts of collaborative text documents. Current revision control techniques only support coarse-grained shared access and are inefficient to retrieve metadata of changes at the sub-document granularity. In this dissertation, we design and implement partial persistent sequences (PPSs) to support real-time collaborations and manage metadata of changes at fine granularities for collaborative text document editing and processing applications. As a persistent data structure, PPSs have two important features. First, items in the data structure are never removed. We maintain necessary timestamp information to keep track of both inserted and deleted items and use the timestamp information to reconstruct the state of a document at any point in time. Second, PPSs create unique, persistent, and ordered identifiers for items of a document at fine granularities (e.g., a word or a sentence). As a result, we are able to support consistent and fine-grained shared access to collaborative text documents by detecting and resolving editing conflicts based on the revision history as well as to efficiently index and retrieve metadata associated with different parts of collaborative text documents. We demonstrate the capabilities of PPSs through two important problems in collaborative text document editing and processing applications: data consistency control and fine-grained document provenance management. The first problem studies how to detect and resolve editing conflicts in collaborative text document editing systems. We approach this problem in two steps. In the first step, we use PPSs to capture data dependencies between different editing operations and define a consistency model more suitable for real-time collaborative editing systems. In the second step, we extend our work to the entire spectrum of collaborations and adapt transactional techniques to build a flexible framework for the development of various collaborative editing systems. The generality of this framework is demonstrated by its capabilities to specify three different types of collaborations as exemplified in the systems of RCS, MediaWiki, and Google Docs respectively. We precisely specify the programming interfaces of this framework and describe a prototype implementation over Oracle Berkeley DB High Availability, a replicated database management engine. The second problem of fine-grained document provenance management studies how to efficiently index and retrieve fine-grained metadata for different parts of collaborative text documents. We use PPSs to design both disk-economic and computation-efficient techniques to index provenance data for millions of Wikipedia articles. Our approach is disk economic because we only save a few full versions of a document and only keep delta changes between those full versions. Our approach is also computation-efficient because we avoid the necessity of parsing the revision history of collaborative documents to retrieve fine-grained metadata. Compared to MediaWiki, the revision control system for Wikipedia, our system uses less than 10% of disk space and achieves at least an order of magnitude speed-up to retrieve fine-grained metadata for documents with thousands of revisions.

<p>Problem: Interim and annual reports are some of the most crucial sources of information regarding companies’ performances. Interested parties such as analysts and investors assess this information and compare it with expectations. Analysts’ expectations of companies’ interim reports are of great importance when analysing the future development of share movement. Possible deviations between analysts’ expectations and actual presented results from the individual companies might change the perceptions of specific future stock prices. Furthermore business sectors have different characteristics and might respond differently to unexpected earnings news. Over- and underperformance of the presented results in relation to analysts’ expectations could create specific stock price movements over a forthcoming period depending on the nature of the report. The authors label this phenomenon as persistent trends.</p><p>Purpose: The purpose of this thesis was to establish whether persistency and trends could be observed in the future development of companies’ stock prices with regard to analysts’ expectations and the true result presented by the companies.</p><p>Method: With a quantitative approach the authors conducted an event study aiming to fulfill the purpose of this thesis. The study consisted of all fourth quarter reports presented 2001 throughout 2004 by the companies presently listed on the Most traded section of the Stockholm stock exchange A-list. The authors defined the nature of the studied reports as positive or negative depending on whether the pre-tax earning exceeded or were lower than the analysts’ expectations. Furthermore the authors constructed a mathematical formula which distinguished if the possible deviation of actual results compared to expectations was significant. The share price performance for two months subsequent to the earnings announcement was recorded and compared with the OMXS30 development for the equivalent time, thereby the authors gathered empirical evidence to fulfill the purpose. Furthermore the data was also divided into business subcategories to provide answers to whether there was uniform response to unexpected earnings information among business sectors.</p><p>Results: The authors presented empirically founded evidence for the existence of persistent trends following the presentation of both positive and negative reports. The authors also rejected the presence of a uniform response to deviating earnings information in the business sectors.</p>

<p>In the last 50 years, a considerable amount of research workhas been completed in the mathematical system theory and theoryof control. Implementation of the results from this researchinto practice has drastically decreased the production costs.Most production processes are highly automated, and the use ofrobots in industry is growing. As far as office, or businessprocesses are concerned, the situation is quite different.Though the office workers and sales personnel have obtainedmuch help from the modern computers, the office and salesprocesses are far behind the production processes on the levelof automation. The computers are used in the office mainly tohelp in performing various activities, e.g., to write a letter,to print an invoice, to complete a transaction, etc. Thecontrol of the business processes in the office remains, to alarge extent, manual. There is a lot to gain if the controlover business processes could be automated, at leastpartially.</p><p>The material presented in this thesis is aimed to supportthe following hypothesis: "<i>The ideas worked out in the Mathematical system theory formodeling and controlling physical processes can be successfullyused for modeling and controlling business processes</i>." Oneof the main ideas of mathematical system theory is to considera process as a set of valid trajectories in a state space, andthis idea is the keystone for the thesis. The thesis startswith reformulating the state-oriented approach for the domainof business processes to show what kind of sate space can beused in this domain. First, the approach is introducedinformally by means of an example. Next, a possibleformalization adjusted to the properties of business processesis discussed. Then, experimental evidences that the methodsuggested in the thesis can be used in practice are presented.The suggested method is also compared with other methods ofbusiness process modeling to find out the areas where it hasadvantages over the other methods. In the conclusion, theresults are summarized, and plansfor the future are drawn.</p><p>Most of the material included in the thesis has beenpublished and presented at international conferences. Thecontribution of this thesis consists in organizing the materialin support of the main hypothesis.</p>

Der Vortrag wurde auf dem 5. Workshop DissOnline: Abschlussworkshop des DFG-Projektes "Aufbau einer Koordinierungsstelle für elektronische Hochschulschriften" am 25. Februar 2005 gehalten. Der Datentransfer elektronischer Hochschulschriften an die Deutsche Bibliothek (DDB) sowie den Südwestdeutschen Bibliotheksverbund (SWB) ist erläutert. Die Technologie zur Erfassung, Aufbereitung und Datenübermittlung ist für das Meldeinterface DDB und SWB äquivalent. Dabei erfolgt die automatische Vergabe von Persistent Identifiern (URN) für jedes Dokument. Die per Onlineformular vom Autor eingetragenen Metadaten werden zur Abholung und Speicherung auf dem Server der Deutschen Bibliothek in das Format XMetaDiss transformiert und über die OAI Schnittstelle zum Download bereitgestellt. Für die in MONARCH achivierten Dissertationen und Habilitationen ist die Langzeitverfügbarkeit und der persistente Zugriff auf den Volltext gesichert.

In this thesis we use computational neural network models to examine the dynamics and functionality of the CA3 region of the mammalian hippocampus. The emphasis of the project is to investigate how the dynamic control structures provided by inhibitory circuitry and cellular modification may effect the CA3 region during the recall of previously stored information. The CA3 region is commonly thought to work as a recurrent auto-associative neural network due to the neurophysiological characteristics found, such as, recurrent collaterals, strong and sparse synapses from external inputs and plasticity between coactive cells. Associative memory models have been developed using various configurations of mathematical artificial neural networks which were first developed over 40 years ago. Within these models we can store information via changes in the strength of connections between simplified model neurons (two-state). These memories can be recalled when a cue (noisy or partial) is instantiated upon the net. The type of information they can store is quite limited due to restrictions caused by the simplicity of the hard-limiting nodes which are commonly associated with a binary activation threshold. We build a much more biologically plausible model with complex spiking cell models and with realistic synaptic properties between cells. This model is based upon some of the many details we now know of the neuronal circuitry of the CA3 region. We implemented the model in computer software using Neuron and Matlab and tested it by running simulations of storage and recall in the network. By building this model we gain new insights into how different types of neurons, and the complex circuits they form, actually work. The mammalian brain consists of complex resistive-capacative electrical circuitry which is formed by the interconnection of large numbers of neurons. A principal cell type is the pyramidal cell within the cortex, which is the main information processor in our neural networks. Pyramidal cells are surrounded by diverse populations of interneurons which have proportionally smaller numbers compared to the pyramidal cells and these form connections with pyramidal cells and other inhibitory cells. By building detailed computational models of recurrent neural circuitry we explore how these microcircuits of interneurons control the flow of information through pyramidal cells and regulate the efficacy of the network. We also explore the effect of cellular modification due to neuronal activity and the effect of incorporating spatially dependent connectivity on the network during recall of previously stored information. In particular we implement a spiking neural network proposed by Sommer and Wennekers (2001). We consider methods for improving associative memory recall using methods inspired by the work by Graham and Willshaw (1995) where they apply mathematical transforms to an artificial neural network to improve the recall quality within the network. The networks tested contain either 100 or 1000 pyramidal cells with 10% connectivity applied and a partial cue instantiated, and with a global pseudo-inhibition.We investigate three methods. Firstly, applying localised disynaptic inhibition which will proportionalise the excitatory post synaptic potentials and provide a fast acting reversal potential which should help to reduce the variability in signal propagation between cells and provide further inhibition to help synchronise the network activity. Secondly, implementing a persistent sodium channel to the cell body which will act to non-linearise the activation threshold where after a given membrane potential the amplitude of the excitatory postsynaptic potential (EPSP) is boosted to push cells which receive slightly more excitation (most likely high units) over the firing threshold. Finally, implementing spatial characteristics of the dendritic tree will allow a greater probability of a modified synapse existing after 10% random connectivity has been applied throughout the network. We apply spatial characteristics by scaling the conductance weights of excitatory synapses which simulate the loss in potential in synapses found in the outer dendritic regions due to increased resistance. To further increase the biological plausibility of the network we remove the pseudo-inhibition and apply realistic basket cell models with differing configurations for a global inhibitory circuit. The networks are configured with; 1 single basket cell providing feedback inhibition, 10% basket cells providing feedback inhibition where 10 pyramidal cells connect to each basket cell and finally, 100% basket cells providing feedback inhibition. These networks are compared and contrasted for efficacy on recall quality and the effect on the network behaviour. We have found promising results from applying biologically plausible recall strategies and network configurations which suggests the role of inhibition and cellular dynamics are pivotal in learning and memory.

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