International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / An Improved AMI (Alternate Mark Inverse) Code used in telemetry system is proposed, its implementation and properties analysis are reported, including error performance analysis, power spectrum analysis, the relationship between acqusition probability of the first frame marker and error threshold and length of frame marker, etc. This type of code has the approximately identical power spectrum performance as the AMI Code. In addition, there have no long continuous zeroes in the data stream, which will cause phase-locked loop to fail. Using the Improved AMI Code, the equal probability of 0 and 1 is changed, which will increase acqusition probability of the first frame marker. Detailed description about how to create the Improved AMI Code is also discussed in this paper.

<p>The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.</p><p>The designed fault detection system showed to work well for the available data. It is, however, recommended that the performance of the system should be evaluated using more data. Another model based on data sampled once every minute for at least a year has to be developed before the system can be fully evaluated. The results shown were:</p><p>• The fault detection system can discover fast and slow changes in bearing temperature.</p><p>• No false alarms were given for measuring faults and sensor faults of the types used in this thesis. If a measuring fault occurs for too long there will be an alarm.</p><p>The fault detection algorithm was also implemented in Delphi to be used in a working system over the Internet where for example trends and alarms will be presented.</p> / <p>Syftet med examensarbetet var att utveckla ett automatiskt feldetekteringssystem för övervakning av bärlagertemperaturen i vattenkraftturbiner. De ingående parametrarna förutom bärlagertemperaturen var kylvattentemperaturen och kylvattenflödet. En enkel statisk modell baserad på data samplat en gång per minut togs fram för att estimera bärlagertemperaturen. Därefter utvecklades en detektor för att upptäcka avvikelser i bärlagertemperaturen baserad på CUSUM-algoritmen. På grund av en för liten mängd data var den framtagna modellen alltför osäker för att kunna implementeras i ett fungerande system.</p><p>Det framtagna feldetekteringssystemet visade sig fungera bra för de data som fanns tillgängliga. Det är däremot rekommenderat att utvärdera systemets prestanda med längre dataserier. En ytterligare modell baserad på minutdata över ett år måste tas fram innan systemet kan fungera på riktigt. De resultat som erhölls var:</p><p>• Feldetekteringssystemet klarar av att upptäcka abrupta och långsamma avvikelser av bärlagertemperaturen.</p><p>• Inga falsklarm ges då det är enstaka mätfel eller givarfel av sådan typ som tagits upp i arbetet. Pågår ett mätfel alltför länge ges dock ett larm.</p><p>Feldetekteringsalgoritmen implementerades även i Delphi för att kunna användas i ett fungerande system över Internet där t.ex. trendkurvor och larmsignaler skall kunna presenteras.</p>

The operational management of Water Distribution Systems (WDS), particularly under failure conditions when the behaviour of a WDS is not well understood, is a challenging problem. The research presented in this thesis describes the development of a methodology for risk-based diagnostics of failures in WDS and its application in a near real-time Decision Support System (DSS) for WDS’ operation. In this thesis, the use of evidential reasoning to estimate the likely location of a burst pipe within a WDS by combining outputs of several models is investigated. A novel Dempster-Shafer model is developed, which fuses evidence provided by a pipe burst prediction model, a customer contact model and a hydraulic model to increase confidence in correctly locating a burst pipe. A new impact model, based on a pressure driven hydraulic solver coupled with a Geographic Information System (GIS) to capture the adverse effects of failures from an operational perspective, is created. A set of Key Performance Indicators used to quantify impact, are aggregated according to the preferences of a Decision Maker (DM) using the Multi-Attribute Value Theory. The potential of distributed computing to deliver a near real-time performance of computationally expensive impact assessment is explored. A novel methodology to prioritise alarms (i.e., detected abnormal flow events) in a WDS is proposed. The relative significance of an alarm is expressed using a measure of an overall risk represented by a set of all potential incidents (e.g., pipe bursts), which might have caused it. The DM’s attitude towards risk is taken into account during the aggregation process. The implementation of the main constituents of the proposed risk-based pipe burst diagnostics methodology, which forms a key component of the aforementioned DSS prototype, are tested on a number of real life and semi-real case studies. The methodology has the potential to enable more informed decisions to be made in the near real-time failure management in WDS.

Background: Alarm interpretation and management are fundamental to managing critically ill patients. 1 There is little research as to the decision process nurses use to prioritize alarms or manage specific monitor parameters. Objective: The purpose of this study is to gain insight into the intricacy of the intensive care unit (ICU) nurses'critical decision process, using a human performance framework, when responding to monitor alarms. Method: Design: Descriptive design using semi-structured interview. Open-ended questions were developed based on the critical decision method (CDM) to explore ICU nurses' critical decision making process related to monitor alarms. Sixteen ICU nurses at a community hospital were interviewed to elicit perceptions and thought processes related to monitor alarms. Results: Responses to monitor alarms were affected by nursing experience, tones of the alarm, nurses' knowledge of the patient's condition as well as immediate visualization of patient to judge the urgency of an alarm. Both advanced beginner and expert nurses had similar initial response to monitor alarms; however, expert nurses added depth to their immediate assessment process by using previous experiences, intuition, and clinical expertise. Advanced beginner nurses frequently look to expert nurses for advice, guidance, and examples of clinical expertise. The majority of nurses had little or no formal training on the cardiac monitors used by that facility and all felt it would be beneficial in monitor alarm management. Conclusion: Understanding the decision-making process used by nurses can guide the development of policies and learning experiences that are crucial clinical support for alarm management.

The thesis deals with vocalizations produced by Eurasian ground squirrels of the genus Spermophilus. It is mainly focused on inter-species and intra-species variability in acoustic structure of alarm calls which are emitted in presence of predators.The major part of the thesis deals with intra-species variability in acoustic structure of the alarm calls in five Eurasian ground squirrels, Spermophilus citellus, S. taurensis, S. xanthoprymnus, S. suslicus and S. fulvus. It has been confirmed that the alarm calls of these ground squirrels show a high level of species specificity. The thesis further describes another vocalizations produced by three Eurasian ground squirrel species, Spermophilus suslicus, S. citellus and S. fulvus, and shows that with the exception of the alarm calls, vocal repertoires of these three ground squirrels are remarkably similar. The last part of the thesis deals with individual distinctiveness of the alarm calls of three Eurasian ground squirrels, Spermophilus citellus, S. taurensis and S. xanthoprymnus. It has been shown that the alarm calls of these species have a significant potential to encode information about caller identity.

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

Valmet har fått önskemål från kunder om att integrera manualer som en del av automationssystemet. Denna rapport visar ett koncept hur det problemet skulle kunna lösas genom att bygga in manualer med funktioner och att texterna finns tillgängliga att läsa i HMI. Målet är att kunna hämta ut mer information ur HMI genom att integrera operatör- och servicemanual i automationssystemet. Metoden för detta arbete har varit att inleda med en litteraturstudie om ämnena: alarm, HMI och dokumentintegration. Efter litteraturstudie började en utvecklingsfas som använde kunskaperna från litteraturstudien för att bygga de inbygga funktionerna. Sista fasen i arbetet var att testa funktionaliteten och utvärdera resultatet. Resultatet blev en ny alarmvy med utökad funktionalitet, som att till exempel visa ytterligare information vid klick, ett automatiskt underhållssystem med låg prestandapåverkan och PDF av manualerna tillgänglig i HMI. Målen med arbetet anses vara uppfyllt då ytterligare larminformation finns att tillgå, ett underhållssystem är implementerat och manual finns att läsa i HMI. Framtida arbete skulle kunna vara att göra alarmvyn mer robust genom att fel upptäcks och korrigeras, ytterligare integrera innehållet i manualerna, förslagsvis hur maskin ska köras skulle kunna integreras. / Valmet has received requests from customers to integrate manuals as part of the automation system. This report shows a concept of how that problem could be solved by incorporating manuals with functions and that the texts are available for reading. The goal is to be able to extract more information from HMI by integrating the operator and service manuals in the automation system. The method for this work was to start with a literature study on the topics: alarm, HMI and document integration. After a literature study, a development phase began that used the knowledge from the literature study to build the products. The final phase of the work was to test the functionality and evaluate the result. The result was a new alarm view with enhanced functionality, such as, for example, displaying additional information at clicks, an automatic maintenance system with low performance impact and PDF of the manuals available in HMI. The goals of the work are considered fulfilled since additional alarm information is available, a maintenance system is implemented, and the manual can be read in HMI. Future work could be to make the alarm view more robust by detecting and correcting errors, further integrating the contents of the manuals, possibly how to run the machine.

A project report submitted to the Faculty of Engineering, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg 1995. / Advances in digital computing technology make it possible to improve the design of the Man Machine Interface (MMI), SCADA and ALARM modules used in electrical utility control centres. to overcome the problem of control staff data overloading. A possible solution is proposed, based on-an explicit representation of a disturbed power system state in addition to quiescent conditions. The structure of modem SCADA, installations is analysed in terms of the computing power of full graphic workstations, the quantities of element data delivered to the control room and the capabilities of intelligent remote terminal units. This analysis indicates that existing designs for the presentation of SCADA data need to change to solve the data overloading-problem. The proposed philosophy moves the focus of attention from the element level up to the device level by grouping and dividing all elements into categories at the RTU and linking them to their parent device, Control staff are notified graphically on the one-line displays, next to the device in question, of the existence of abnormal elements by category. The element state details for the device are only displayed on demand, resulting in a 95% reduction of alarm text messages. Suggestions are made as to the software functions needed at tbe RTU and the workstation to assist with the display of system data. Lastly racommendations are offered to reduce maintenance by standardising and pre-ordering device element data. / AC2017

Digital services involving large systems with multiple users are ubiquitous in modern society. The systems are often complicated and made up of multiple devices and communication protocols. A fundamental problem in this context is how the behavior of a system changes as the number of users vary. In particular, when do the systems’ resources saturate and how does the system behave when close to saturation. Performance testing is key for addressing this fundamental problem. Performance testing is the scope of this project. Performance tests can be used for inference of, for example, a system's scalability. Furthermore, it can be used to provide general guarantees on the services that can be delivered. Performance testing at the company Phoniro AB is considered. The platform Phoniro Care is the back-end service for the company’s products. The Phoiro 6000 system is one of the products that uses Phoniro Care. The system allows for multiple users and offers alarm services. The primary focus of this project is to determine the behavior of that system during varying levels of simulated load, and furthermore analyze the data extracted from such simulations and tests. The open source software JMeter was used as the tool for performance testing. It was selected from a set of candidate tools that have been evaluated in the literature based on various performance criteria. The results are presented by graphs showing the time evolution of different performance indicators. A conclusion from this work is that the implemented performance testing framework helps to answer questions about the systems’ behavior. Questions that are important for the company’s further development and expansion of the system. Furthermore, the proposed framework establishes a foundation for further inquiries on the subject.

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