Diese Dissertation umfasst drei Aufsätze über die Rolle von Informationsintermediären und Intermediäre mit Aufsichtsfunktionen in Kapitalmärkten. Der erste Aufsatz untersucht, ob sich verschiedene Leerverkäufer bei ihrer Auswahl von Zielunternehmen anhand von sichtbaren Merkmalen unterscheiden. Die Ergebnisse zeigen, dass Hedgefonds und Investmentmanager im Durchschnitt größere und jüngere Unternehmen bevorzugen, während sich Banken auf Unternehmen mit weniger Restatements der Finanzdaten und einem höheren Verschuldungsgrad konzentrieren. Der zweite Aufsatz beschreibt, wie Unternehmen auf aktivistische Leerverkäuferberichte reagieren. Es wird festgestellt, dass die Antwortrate erheblich steigt, wenn der Bericht von deutlich negativen abnormalen Renditen begleitet wird und wenn die Leerverkäufer neue Beweise vorlegen. Dies stimmt mit der Vorstellung überein, dass Leerverkäufer als Informationsintermediäre fungieren können. Eine Nichtbeantwortung ist außerdem ist mit einer weniger negativen Aktienkursreaktion bei Veröffentlichung und mit weniger nachteiligen Ergebnissen verbunden. Die dritte Aufsatz fokusiert sich auf so-genannte Monitoring Trustees. Sie sind bei der Überwachung von Banken behilflich, die in der Europäischen Union während der letzten Finanzkrise staatliche Beihilfen erhalten haben. In einer von Hand gesammelten Stichprobe werden die Merkmale und Aufgaben dieser neu implementierten Aufseher und ihre Rolle im Zusammenhang mit dem Berichtsverhalten der Banken untersucht. Die Ergebnisse deuten darauf hin, dass diese zusätzlichen Aufseher die Transparenz und das Berichtsverhalten der Banken bei der Finanzberichterstattung beeinflussen können, insbesondere wenn die Berichterstattung über Kreditverluste und Anpassungen der Geschäftsberichte berücksichtigt werden. Der zweite Aufsatz wurde im Journal of Accounting Research (https://doi.org/10.1111/1475-679X.12356) publiziert. / This dissertation comprises three essays on the role of information and monitoring intermediaries in capital markets. The first essay investigates whether different short sellers vary in their selection of target firms using observable firm characteristics. Results show that hedge funds and investment managers on average prefer larger and younger firms, whereas banks focus on firms with fewer restatements and a higher leverage. The second essay provides descriptive evidence on how firms respond to activist short seller reports and how these responses are associated with outcomes for the targeted firms. It finds that the response rate increases substantially when the report is accompanied by significantly negative abnormal returns and when the short sellers provide new evidence which is consistent with the idea of short sellers acting as information intermediaries. Not responding is associated with a less negative stock price response when the report is released and fewer adverse outcomes. The third essay shifts the attention to Monitoring Trustees who assist in the supervision of banks that have received state aid in the European Union during the last financial crisis. It explores in a hand-collected sample the characteristics and duties of these newly implemented monitors and it studies the role of these supranational monitors and the banks’ reporting behavior. Results suggest that these additional supervisors can influence the banks financial reporting transparency and reporting behavior when mainly loan loss reporting and restatements are accounted for. The second essay has been published in the Journal of Accounting Research (https://doi.org/10.1111/1475-679X.12356).

The objective of this project is to design an antenna for use in the electronic monitoring of persons convicted of non-violent crimes. If implemented, electronic monitoring will lighten the load on the South African prison system. Electronic monitoring makes use of an electronic tether connected to the person being monitored. This led to specific performance requirements and size constraints being placed on the antenna. The antenna should be physically small while still being able to perform as specified. It is also necessary to test the design with various frequencies, to determine the best possible frequency to use. It was decided to use a Transformer Coupled Loop (TCL) antenna, after various designs were considered. The TCL antenna can be used in various configurations, with some of these configurations being simulated to determine the best antenna structure to use. After various antenna structures were discarded, a specific antenna structure emerged as a possible solution, which was then optimised to deliver the best possible performance. The optimised antenna model was constructed to test the antenna performance. The receiving antenna was a directional Log-Periodic Dipole Antenna (LPDA), connected to a spectrum analyser. Tests were conducted in an open-field environment to minimise the effect of reflections. The azimuth- and elevation radiation patterns for the antenna could be compared to the simulated results. The same tests were performed with the antenna attached to a saline solution bag, simulating the effects of the human body on the antenna performance. The radiation patterns obtained from the measured results proved to be similar to the simulated results for both frequencies tested. When making use of the human analogue, the radiation pattern tended to be more omnidirectional in both the azimuthand elevation planes. These results are ideal, since omnidirectional communication by the tethering device is required by a security application. The primary objective was achieved, together with the secondary objectives of comparing different frequencies. / Thesis (M.Ing. (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2012

The objective of this project is to design an antenna for use in the electronic monitoring of persons convicted of non-violent crimes. If implemented, electronic monitoring will lighten the load on the South African prison system. Electronic monitoring makes use of an electronic tether connected to the person being monitored. This led to specific performance requirements and size constraints being placed on the antenna. The antenna should be physically small while still being able to perform as specified. It is also necessary to test the design with various frequencies, to determine the best possible frequency to use. It was decided to use a Transformer Coupled Loop (TCL) antenna, after various designs were considered. The TCL antenna can be used in various configurations, with some of these configurations being simulated to determine the best antenna structure to use. After various antenna structures were discarded, a specific antenna structure emerged as a possible solution, which was then optimised to deliver the best possible performance. The optimised antenna model was constructed to test the antenna performance. The receiving antenna was a directional Log-Periodic Dipole Antenna (LPDA), connected to a spectrum analyser. Tests were conducted in an open-field environment to minimise the effect of reflections. The azimuth- and elevation radiation patterns for the antenna could be compared to the simulated results. The same tests were performed with the antenna attached to a saline solution bag, simulating the effects of the human body on the antenna performance. The radiation patterns obtained from the measured results proved to be similar to the simulated results for both frequencies tested. When making use of the human analogue, the radiation pattern tended to be more omnidirectional in both the azimuthand elevation planes. These results are ideal, since omnidirectional communication by the tethering device is required by a security application. The primary objective was achieved, together with the secondary objectives of comparing different frequencies. / Thesis (M.Ing. (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2012

Recent guidelines recommend oxygen saturation (SpO(2)) levels of 90%-95% for preterm neonates on supplemental oxygen but it is difficult to discern such levels with current pulse oximetry sonifications. We tested (1) whether adding levels of tremolo to a conventional log-linear pulse oximetry sonification would improve identification of SpO(2) ranges, and (2) whether adding a beacon reference tone to conventional pulse oximetry confuses listeners about the direction of change. Participants using the Tremolo (94%) or Beacon (81%) sonifications identified SpO(2) range significantly more accurately than participants using the LogLinear sonification (52%). The Beaton sonification did not confuse participants about direction of change. The Tremolo sonification may have advantages over the Beacon sonification for monitoring SpO(2) of preterm neonates, but both must be further tested with clinicians in clinically representative scenarios, and with different levels of ambient noise and distractions. Crown Copyright (C) 2016 Published by Elsevier Ltd. All rights reserved.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / A strategy for addressing the complexity of problem identification and notification by autonomous telemetry monitoring software is discussed. The Extreme Ultraviolet Explorer (EUVE) satellite's science operations center (ESOC) is completing a transition to autonomous operations. Originally staffed by two people, twenty-four hours every day, the ESOC is nearing the end of a phased transition to unstaffed monitoring of the science payload health. To develop criteria for the implementation of autonomous operations we first identified and analyzed potential risk areas. These risk areas were then considered in light of a fully staffed operations model, and in several reduced staffing models. By understanding the accepted risk in the nominal, fully staffed model, we could define what criteria to use in comparing the effectiveness of reduced staff models. The state of the scientific instrument package for EUVE is evaluated by a rule-based telemetry processing software package. In the fully automated implementation, anomalous states are characterized in three tiers: critical to immediate instrument health and safety, non-critical to immediate instrument health and safety, and affecting science data only. Each state requires specific action on the part of the engineering staff, and the response time is determined by the tier. The strategy for implementing this prioritized, autonomous instrument monitoring and paging system is presented. We have experienced a variety of problems in our implementation of this strategy, many of which we have overcome. Problems addressed include: dealing with data dropouts, determining if instrument knowledge is current, reducing the number of times personnel are paged for a single problem, prohibiting redundant notification of known problems, delaying notification of problems for instrument states that do not jeopardize the immediate health of the instrument, assuring a response to problems in a timely manner by engineering staff, and communicating problems and response status among responsible personnel.

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The Extreme Ultraviolet Explorer (EUVE) Science Operations Center at UC Berkeley was recently successful in implementing an automated monitoring system that allowed reduced operations staffing from 24 hours per day to 9 hours per day. The payload safety is monitored exclusively by artificial intelligence (AI) telemetry-processing systems for 16 hours per day. At launch, the EUVE Science Operations Center was staffed and operated as a typical satellite control center, receiving real-time and tape recorder data 24 hours per day. From September 1993 through February 1995, EUVE science operations were redesigned in a phased, low-cost approach. A key factor in the implementation was to utilize existing personnel in new roles through additional training and reorganization. Through- out this period, EUVE guest observers and science data collection were unaffected by the transition in science operations. This paper describes the original and actual implementation plan, staffing phases, and cost savings for this project. We present the lessons learned in the successful transition from three-shift to one-shift operations.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper was prepared as part of the team design competition for a graduate level course given at the University of Canterbury, in Christchurch, New Zealand. It presents a high level design of an automated telemetering system for tracking and monitoring a number of land-based animals as small as a rabbit. The primary purpose of the system is to monitor both desirable and undesirable species of wildlife in the New Zealand bush in order to better understand their living habits and environmental requirements. The typical conditions monitored are body temperature, moisture levels, light intensity, physical activity, and heart rate. All critical aspects of the telemetering system have been specified, including the sensors, transmitter/receiver, and telemetry packet and frame design. A calculation of the link budget for the system has been performed.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / The Vehicle Monitoring System based on GPRS is a system using GPRS network to transmit data, including location data, time data and so on .It has many advantages compared with those systems based on other communication modes. The key of the system lies in how to build up the connection with exterior data network. In this paper, the constitution of the system is introduced, and the course of building up connection with exterior data network is described in detail.

This research applies a recently developed dynamic state-estimation based protection scheme, the settingless protection, to the photovoltaic (PV) industry for the first time. At this time, the proposed protection algorithm has been implemented on traditional protection zones for individual power system devices, but this research extends this protection to a microgrid, specifically, a system of PV network composed of several PV modules. Several illustrative examples on various anomalies such as high impedance faults and shorted-out PV modules have been provided to demonstrate the effectiveness of this protection scheme. The detection of these anomalies has been demonstrated in the presence of changing atmospheric conditions, and with the operation of maximum power point tracking (MPPT) equipped dc-dc converters. This protection scheme requires an accurate model of the PV module, therefore, a two-diode PV model has been developed using quadratic integration modeling. In this PV model development, a scaling factor is applied to the Taylor series expansion of the exponential terms of the model of the PV module. Then the higher order terms of the Taylor series expansion are reduced to at most second order terms using the quadratization technique. Furthermore, a novel approach for extracting the PV parameters, namely, the ideality constants, leakage currents, PV module internal current, shunt and series resistances, has been presented. A comparison was performed between numerically generated data using the determined PV module parameters and data measurements from a physical PV module. It was shown that the maximum error from this comparison was below 0.12A, and less than 0.05A around the maximum power point region of the PV modules used for this research. The residual data from the PV array protection scheme has been used to develop a method for identifying the location of faulted PV modules. Also, condition-based monitoring of the PV array system has also been presented with examples. From the PV array system monitoring, the shading and underperformance of a PV module have been identified. From the contributions of this research, an accurate module of the PV array has been developed in a form that can be integrated with other power system devices. This accurate module can be used for state estimation of the PV array, load flow analysis, short circuit analysis, and other power system analytical studies. Also, by determining the location of the faulted PV module, the time to identify this faulted PV module in a large PV installation is drastically reduced. Lastly, by identifying shading conditions and underperforming PV modules, the PV system operator can quickly bring the underperforming module or modules to optimal performance, thereby, maximizing the power yield of the PV array, and maximizing the revenue of the PV system owner.

published_or_final_version / Orthopaedic Surgery / Doctoral / Doctor of Philosophy