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Protection of the agriculture and food infrastructure, defined as "the physical production and distribution systems critical to supporting national security and economic well-being, including all activities essential to food, feed, and fiber production, including all techniques for raising and processing livestock," is the responsibility of all stakeholders in the food supply chain (Spellman, 2008, p.8). Though many stakeholders emerge in the chain, producers are the primary line of defense to a disease epidemic. Many factors influence livestock producers‘ protective action decision process in relation to biological hazards. By identifying these factors in a specific producer population, more effective preparedness programs and messages can be developed by risk communicators. The purpose and objectives of this study determined Texas and Southwestern Cattle Raisers Association (TSCRA) members‘ perceptions of vulnerability to the Texas cattle industry, perceived emergency preparedness level, barriers to adoption of protective actions, and sources of animal health information. This study targeted 7,661 members of the TSCRA. An online survey questionnaire developed from previous research with similar populations allowed TSCRA members to respond to questions related to the objective of this study. A representative sample of TSCRA members from Texas, Oklahoma, and New Mexico responded to the survey. Recognizing susceptibility to biological hazards, TSCRA members identified high levels of perceived trust and reliability in local veterinarians as a source of information, consistent with previous studies. Although the majority of members reported they did not have a biosecurity plan implemented on their operations, they did recognize the necessity of preventative practices. TSCRA members were neutral on all barriers to adoption of protective actions; however, the barrier "lack of information" was rated higher by means as a barrier to adoption of protective actions. When investigating differences among noncommercial and commercial operations managed by TSCRA members, no statistical differences were identified in this study. However, when investigating differences among TSCRA members and number of cattle managed, a weak positive correlation was identified for perception of hazard by threat in relation to more animals managed. Findings of this study confirmed sources stating that the agriculture and food infrastructure is vulnerable to biological hazards as perceived by livestock owners (Motes, 2007; Spellman, 2008). Ashlock (2006) and Riley (2007) found similar perspectives of vulnerability among Oklahoma and Kansas producers further strengthening the need to protect the agriculture and food critical infrastructure as outlined by Homeland Security Presidential Directive – 9 (HSPD-9, 2004). Since it was determined that veterinarians are perceived to be the most reliable and trustworthy source of information by TSCRA members, local opinion leaders, such as veterinarians, should engage in train-the-trainer programs to ensure a consistent risk communication message is being disseminated.

The rotor shaft of a synchronous machine can experience severe mechanical stress due to torque pulsations during a pole-slip condition. All pole-slip protection relays currently on the market use the impedance pole-slip protection method to detect a pole-slip. No commercial relay currently available can predict accurately when a generator is about to experience a damaging pole-slip. All the relays will only trip a generator after it has pole-slipped one or more times. Severe mechanical damage could be caused to a machine after only one pole-slip. It is therefore essential to enhance pole-slip protection relays to such an extent that it can trip a generator before it pole slips. The proposed pole-slip protection function must predict when a generator will become unstable during a network fault. As soon as instability is predicted, the generator must be tripped before the fault is cleared to avoid damaging post-fault torque effects. Conventional impedance pole-slip protection methods are are also discussed and the shortcomings of impedance pole-slip protection are investigated. The new pole-slip protection function was designed by using PSCAD. Detailed PSCAD simulations on different network configurations proved that the new pole-slip protection function will trip a generator before a damaging pole-slip occurs. The new pole-slip protection function was also implemented on an ABB REM543 multifunctional protection relay and tested on a RTDS. The concept of the new pole-slip function was successfully demonstrated on the protection relay. The operation of conventional impedance scheme relays was compared with the proposed pole-slip function for different fault conditions. Although the new pole-slip protection function is more complex than the existing impedance functions, it was concluded that similar skills are required to test and commission the new protection function. The new pole-slip function outperforms the impedance protection methods, since the new protection function can trip the generator before it pole-slips. / PhD (Electrical Engineering), North-West University, Potchefstroom Campus, 2011

The rotor shaft of a synchronous machine can experience severe mechanical stress due to torque pulsations during a pole-slip condition. All pole-slip protection relays currently on the market use the impedance pole-slip protection method to detect a pole-slip. No commercial relay currently available can predict accurately when a generator is about to experience a damaging pole-slip. All the relays will only trip a generator after it has pole-slipped one or more times. Severe mechanical damage could be caused to a machine after only one pole-slip. It is therefore essential to enhance pole-slip protection relays to such an extent that it can trip a generator before it pole slips. The proposed pole-slip protection function must predict when a generator will become unstable during a network fault. As soon as instability is predicted, the generator must be tripped before the fault is cleared to avoid damaging post-fault torque effects. Conventional impedance pole-slip protection methods are are also discussed and the shortcomings of impedance pole-slip protection are investigated. The new pole-slip protection function was designed by using PSCAD. Detailed PSCAD simulations on different network configurations proved that the new pole-slip protection function will trip a generator before a damaging pole-slip occurs. The new pole-slip protection function was also implemented on an ABB REM543 multifunctional protection relay and tested on a RTDS. The concept of the new pole-slip function was successfully demonstrated on the protection relay. The operation of conventional impedance scheme relays was compared with the proposed pole-slip function for different fault conditions. Although the new pole-slip protection function is more complex than the existing impedance functions, it was concluded that similar skills are required to test and commission the new protection function. The new pole-slip function outperforms the impedance protection methods, since the new protection function can trip the generator before it pole-slips. / PhD (Electrical Engineering), North-West University, Potchefstroom Campus, 2011

Magistro baigiamajame darbe atskleista, išanalizuota, įvertinta apsaugos principų įgyvendinimas teisės aktais, atskleistas aplinkos apsaugos principų turinys ir samprata, išanalizuota kaip aplinkos apsaugos principai įtvirtinti tarptautinės teisės, Europos Sąjungos bei Lietuvos teisės sistemose. Nors aiškaus aplinkos apsaugos principų sąrašo nėra, šiame magistro baigiamajame darbe išanalizuoti dominuojantys teisės aktuose aplinkos apsaugos principai, kurie teisės mokslininkų yra išskiriami kaip pagrindiniai aplinkos apsaugos principai turintys didelę įtaką visai aplinkos apsaugos politikai bei teisei. Aplinkos apsaugos principai yra pagrindas visos aplinkos apsaugos teisės sistemos, todėl šio darbo iškeltas tikslas- išanalizuoti , kokie aplinkos apsaugos principai labiausiai dominuoja teisės aktuose, apibrėžti šių principų sampratą, turinį, reglamentavimą, nustatyti kokiais teisės aktais ir kaip šie principai yra įgyvendinami Lietuvos aplinkosaugos teisėje. Siekiant darbo tikslo, analizuojama metodinė, norminė, specialioji leteratūra, analizuota teismų praktika. Apibendrinus darbo rezultatus, galima teigti, kad įgyvendinant aplinkos apsaugos principus Lietuvos teisinėje sistemoje yra priimami ir keičiami nacionaliniai teisės aktai, priimamos aplinkos apsaugos strategijos, formuojama teismų praktika. Tačiau šiuo metu tiek Europos Sąjungos tiek nacionaliniai teisės aktai yra nesistemingi, dažnai keičiami ir tai sukelia tam tikras ne tik aplinkos apsaugos principų... [toliau žr. visą tekstą] / Currently, the environmental protection is considered to be one of the priorities for national policies and warrants increasing public interest in it and legal regulation. In legal literature it is recognized that the principles are the main provisions on which legal regulation is based and the law is realized. Legal norms are based on these principles they are used in practice of courts when eliminating the conflict of laws and fill in the gaps in law. Therefore, it is obvious that the principles have great importance to the legal system and at the same time to the public relations. Gradually formed principles of environmental protection influenced the content of environmental protection norms and their implementation. Legal norms are implemented on the basis of legal regulation and the legal relations are founded on their basis. Therefore, in this master's work the final implementation of the principles in environmental protection legislation will be analyzed. In view of the fact that international law has priority over national law and the fact that Lithuania is a member of the European Union and the principle of supremacy of Community law therefore is applicable to Lithuanian legal system, the aim of this Master’s thesis is to reveal the content and concept of principles of environmental protection and to analyze how environmental principles are defined in international law, the European Union low and in the legal system of Lithuania. Although there isn`t any clear... [to full text]

The fast clearing of faults is essential for preventing equipment damage and preserving the stability of the power transmission systems with smaller operating margins. This thesis examined the application of fault generated transients for fast detection and isolation of faults in a transmission system. The basis of the transient based protection scheme developed and implemented in this thesis is the fault current directions identified by a set of relays located at different nodes of the system. The direction of the fault currents relative to a relay location is determined by comparing the signs of the wavelet coefficients of the currents measured in all branches connected to the node. The faulted segment can be identified by combining the fault directions identified at different locations in the system. In order to facilitate this, each relay is linked with the relays located at the adjacent nodes through a telecommunication network. In order to prevent possible malfunctioning of relays due to transients originating from non-fault related events, a transient recognition system to supervise the relays is proposed. The applicability of different classification methods to develop a reliable transient recognition system was examined. A Hidden Markov Model classifier that utilizes the energies associated with the wavelet coefficients of the measured currents as input features was selected as the most suitable solution. Performance of the protection scheme was evaluated using a high voltage transmission system simulated in PSCAD/EMTDC simulation software. The custom models required to simulate the complete protection scheme were implemented in PSCAD/EMTDC. The effects of various factors such as fault impedance, signal noise, fault inception angle and current transformer saturation were investigated. The performance of the protection scheme was also tested with the field recorded signals. Hardware prototypes of the fault direction identification scheme and the transient classification system were implemented and tested under different practical scenarios using input signals generated with a real-time waveform playback instrument. The test results presented in this thesis successfully demonstrate the potential of using transient signals embedded in currents for detection, localization and recognition of faults in transmission networks in a fast and reliable manner.

In sächsischen Betrieben wurde bei unterschiedlichen Bodenbearbeitungssystemen die Wechselwirkung zwischen Bodenbearbeitung, Nährstoffversorgung und Pflanzenschutz untersucht. Bei den Bodenbearbeitungssystemen »Pfluglos« und »Konventionell« wurde die Wirkung auf das Nährstoffverhalten im Boden, auf das Nützlingsvorkommen, die Unkrautzusammensetzung und auf pilzliche sowie tierische Schaderreger beurteilt. Es zeigt sich, dass eine zu enge Fruchtfolge die Pflanzenschutzprobleme verschärft. Die Bodenbearbeitung hat entscheidenden Einfluss auf die Artenzusammensetzung, Artenzahl und Unkrautdichte. Das Durchwuchsproblem, eines der Hauptprobleme der nicht wendenden Bodenbearbeitung, mit reduziertem Herbizidaufwand in den Griff zu bekommen, ist nur begrenzt möglich. Im Winterweizen tritt Septoria tritici, DTR und Ährenfusarium bei nicht wendender Bodenbearbeitung mit Vorfrucht Mais oder Stoppelweizen verstärkt auf. Dauerhaft Pfluglos-Flächen der Lössstandorte zeigen einen höheren Gesamt-Behandlungsindex bei Winterweizen. Pfluglose Flächen haben ein höheres Vorkommen an Feldmäusen und Ackerschnecken.

Thesis (M.A.)--University of North Texas, Aug., 2007. / Title from title page display. Includes bibliographical references.

Thesis (Ph. D.)--University of New South Wales, 2002. / Also available online.

Thesis (doctoral)--Berlin, Humboldt-Universiẗat, 2006. Humboldt-Universiẗat, Diss.--Berlin, 2006. / Literaturverz. S. 247 - 268. Includes bibliographical references (p. 247-268) and index.