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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

HPM-vapen vs. kommersiell UAV

Eriksson, Kjell January 2016 (has links)
Detta arbete i militärteknik studerar om högeffektpulsad mikrovågsstrålning kan uppnå verkan mot kommersiella UAV. Analysen genomförs på två olika icke-dödliga HPM-vapen. Data hämtas från ett scenario där vapenverkan innebär hög risk för skada på tredje man. En Försvarsmaktsstudie har konstaterat att Luftvärnsbataljon saknar förmåga att verka mot små UAV.Dagsaktuell kunskap har inhämtats om scenariots miljö samt från forskning och industri genom studiebesök. Inhämtad kunskap har möjliggjort en logisk-matematisk parameterstudie på ett scenario med militärtekniskt perspektiv. Analysens slutsatser är att kommersiella UAV innehar låg skyddsnivå, att beslut om insats underlättas i alla miljöer och att en elektronisk sköld i form av HPM-vapen skyddar en stor volym samtidigt. HPM-vapen kan inte som ensamt vapensystem stå för skydd och uppnå säkerställd verkan mot kommersiell UAV. HPM-vapen kan däremot komplettera övriga verkanssystem och göra luftförsvaret starkare genom system av system. HPM-vapen kan bidra till att minska ett befintligt förmågeglapp mot kommersiella UAV. / This paper in military technology discusses whether high power microwaves can affect commercial UAVs. Two non-lethal HPM-weapons are analyzed. The data is collected from a scenario where there is a high risk for collateral damage. A Swedish Armed Forces study stated that the Air Defence Battalion lacks ability to affect small UAVs. The latest knowledge is obtained from the environment in the scenario, from research and from the industry. This knowledge has enabled a logical-mathematical parametric study on the scenario within a military perspective. The result of the study is the assessment that commercial UAVs are assessed to have low protection factor, facilitates decision to act in all environments and provides an electronic shield protection of a large surface at the same time. HPM-weapons can´t stand as a single system for protection against commercial UAVs and achieve guaranteed effect. However, HPM-weapons can complement other weapon systems and thus make the air defense stronger through systems of systems. HPM-weapons can reduce the capability deficiency against commercial UAVs.
12

Developing a Test Method to Evaluate the Blackout Effect of Uncoated Curtains at Varying Angles

Muminovic, Sara, Lindén, Christina January 2023 (has links)
This study aimed to explore the integration of varying angles in small-scale measurements and assess the light transmission performance of uncoated curtains. A total of four curtains were evaluated: blackout curtain samples 1 and 2 had a weft satin structure, while daytime curtain samples 3 and 4 consisted of a twill structure. The primary challenge was the inadequacy of a standardized test method for measuring the blackout effect, which led to inefficiencies and resource consumption for Company X. To address this, the study emphasized the need to investigate and establish a reliable and efficient evaluation method for uncoated curtains. By developing a standardized test method, it is possible to reduce waste material, labor costs, and resource consumption, enabling companies to operate more efficiently, sustainably, and responsibly. In the pursuit of understanding the blackout effect and evaluating the structural parameters of uncoated curtains, this study explored various test methods and parameters. More specifically, parameters such as air permeability, porosity, and thickness together with microscopic evaluation, were investigated to shed light on their influence on light transmission. The voids in the fabric were found to be a significant factor, along with porosity and air permeability, which demonstrated a correlation with lower values for the blackout curtains. The construction of the test method in a small-scale required a controlled space in the form of a lightbox. Light proofing of the box was required and successfully achieved in Prototype 1 using plywood, sealing strips, and fixtures, resulting in a lower lux value compared with the previous internal method. Objective measurements using the Konica CL-500A lux meter provided a repeatable and reliable test method with a lower tolerance value of 0,05 lx. The developed test method, theoretical Prototype 2, incorporates different sun angles by adjusting the curtain’s position, in the angles of 0°, 15°, 30°, 45° and 60°, and the rotation of the sample within 0° to 360° in intervals of 45°. The important parameters of weft density and the subsequent increase in weight were key factors in the results of light transmission, air permeability, and porosity. Furthermore, properties of the uncoated curtains such of continuous filaments and darker color showed a higher blackout effect. After the identification of complications with the lamp used in the measurement, there has been a focus on discussing the significance of a light diffuser. Additionally, alternative approaches to measure light transmission have been presented, such as digital image analysis and air permeability.
13

THE X-33 EXTENDED FLIGHT TEST RANGE

Mackall, Dale A., Sakahara, Robert, Kremer, Steven E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Development of an extended test range, with range instrumentation providing continuous vehicle communications, is required to flight-test the X-33, a scaled version of a reusable launch vehicle. The extended test range provides vehicle communications coverage from California to landing at Montana or Utah. This paper provides an overview of the approaches used to meet X-33 program requirements, including using multiple ground stations, and methods to reduce problems caused by reentry plasma radio frequency blackout. The advances used to develop the extended test range show other hypersonic and access-to-space programs can benefit from the development of the extended test range.
14

PLASMA SHEATH CHARACTERIZATION FOR TELEMETRY IN HYPERSONIC FLIGHT

Starkey, Ryan P., Lewis, Mark J., Jones, Charles H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / During certain hypersonic flight regimes, shock heating of air creates a plasma sheath resulting in telemetry attenuation or blackout. The severity of the signal attenuation is dependent on vehicle configuration, flight trajectory, and transmission frequency. This phenomenon is investigated with a focus placed on the nonequilibrium plasma sheath properties (electron concentration, plasma frequency, collision frequency, and temperature) for a range of flight conditions and vehicle design considerations. Trajectory and transmission frequency requirements for air-breathing hypersonic vehicle design are then addressed, with comparisons made to both shuttle orbiter and RAM-C II reentry flights.
15

PLASMA TELEMETRY IN HYPERSONIC FLIGHT

Starkey, Ryan P., Lewis, Mark J., Jones, Charles H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / Problems associated with telemetry blackout caused by the plasma sheath surrounding a hypersonic vehicle are addressed. In particular, the critical nature of overcoming this limitation for test and evaluation purposes is detailed. Since the telemetry blackout causes great concern for atmospheric cruise vehicles, ballistic missiles, and reentry vehicles, there have been many proposed approaches to solving the problem. This paper overviews aerodynamic design methodologies, for which the required technologies are only now being realized, which may allow for uninterrupted transmission through a plasma sheath. The severity of the signal attenuation is dependent on vehicle configuration, trajectory, flightpath, and mission.
16

Alcohol responses, cognitive impairment, and alcohol-related negative consequences

Quinn, Patrick Donovan 18 September 2014 (has links)
Under frameworks such as Alcohol Myopia Theory, a body of literature has developed demonstrating how alcohol intoxication can increase behavioral risk-taking, potentially via impaired inhibition of prepotent behavioral responses. A separate area of research has shown that responses to alcohol intoxication are not homogenous across the population. Whereas most previous research has considered alcohol responses in relation to risk for alcohol use disorders, the present investigation tested whether they may additionally contribute to the acute effects of alcohol on drinking-episode-specific cognitive and behavioral consequences. We recruited 82 moderate-to-heavy drinking emerging adults to each complete 2 research protocols: a placebo-controlled, within-subject, counterbalanced alcohol challenge in a simulated bar laboratory and a 21-day, event-level self-monitoring follow-up. Replicating previous research, the alcohol challenge increased heart rate and subjective stimulant-like and sedative-like responses and impaired psychomotor performance and response inhibition. Individual differences in subjective stimulation but not sedation were significantly associated with inhibitory impairment. In the event-level follow-up, we found little evidence that alcohol responses elevated risk for adverse behavioral outcomes, although evidence was stronger that alcohol responses were associated with alcohol-induced memory blackout. Whether and how alcohol responses relate to the physiological, cognitive, and behavioral consequences of alcohol intoxication may depend on a) the quality of the response (e.g., stimulation vs. sedation), b) the type of outcome (e.g., response inhibition vs. blackout vs. behavioral risk-taking), and c) whether perceptions of alcohol-induced effects may contribute to emerging adults' evaluations of risk (e.g., driving after drinking and riding with a drinking driver). / text
17

Pattern Recognition of Power Systems Voltage Stability Using Real Time Simulations

Beeravolu, Nagendrakumar 17 December 2010 (has links)
The basic idea deals with detecting the voltage collapse ahead of time to provide the operators a lead time for remedial actions and for possible prevention of blackouts. To detect cases of voltage collapse, we shall create methods using pattern recognition in conjunction with real time simulation of case studies and shall develop heuristic methods for separating voltage stable cases from voltage unstable cases that result in response to system contingencies and faults. Using Real Time Simulator in Entergy-UNO Power & Energy Research Laboratory, we shall simulate several contingencies on IEEE 39-Bus Test System and compile the results in two categories of stable and unstable voltage cases. The second stage of the proposed work mainly deals with the study of different patterns of voltage using artificial neural networks. The final stage deals with the training of the controllers in order to detect stability of power system in advance.
18

Připravenost Nemocnice Strakonice, a.s. na výpadek kritické infrastruktury / The preparedness of Hospital Strakonice to critical infrastructure failure

VODVÁŘKA, Martin January 2019 (has links)
The failure of critical infrastructure is one of the most serious threats, especially in health care. Hospitals and health care facilities play an irreplaceable role, so it is essential to maintain the capacity and responsiveness of the health care facility as a whole during the blackout period. In energy, which is one of the areas of critical infrastructure, power outages can occur at any time, so the hospital should be unconditionally prepared for this crisis situation and the resulting impacts. The theoretical part defines the basic concepts in the health care system located in crisis preparedness and crisis planning, as well as necessary documentation and electrical regulations. The following chapter deals with the critical infrastructure from the perspective of national and international legislative documents and links to the means for its protection. The last part explains the principle of the electricity system of the Czech Republic and describes the production, transmission and distribution of electricity. The topic of Blackout outlines the issue of domestic and foreign cases. The practical part introduces the environment of the Hospital Strakonice, a.s., further describes the available alternative sources of electric energy and legislative standards of the company, on the principles of which it respects crisis preparedness. Three specific cases explain how critical infrastructure failures can be addressed, prevent unwanted situations, respond to problems promptly, and take remedial action. For elaboration of my diploma thesis I used basic scientific procedures which are observation, consultation, analysis and comparison. The aim of the thesis was to map the readiness of the health and non-health part of the hospital to the impact of the failure of critical infrastructure, which could be described as satisfactory. The findings will be forwarded to the Chairman of the Board of Directors and the Crisis Management Department of the Strakonice Hospital, a.s. to assess the possible consequences and effective preparedness for critical infrastructure failures. The results can be used as study material.
19

Výpadky proudu v Nemocnici Jihlava. / The power outages in the hospital Jihlava.

CHVÁTALOVÁ, Jana January 2014 (has links)
Health - without a doubt - is one of the most precious gifts and it is one of the most important values for each of us. The human body fascinates humanity throughout its existence. Since the beginning of the first medicinal extracts to modern robotic surgery, people strive for the same - to prevent diseases, full recovery of health or to bring closer this state. The whole developed society is interested in our good health. It is necessary to ensure the functional part of the infrastructure, so called critical infrastructure. Unplanned power blackout can have disastrous consequences not only for the patients. Plenty of electrical energy is required for the functioning of hospital. The electrical network in the hospital is very fragile. It is necessary to have alternative sources of electricity in hospital. For each hospital is a priority ability to reliably protect the power grid to avoid damaging consequences of its lack. This thesis entitled "Power blackout in Jihlava hospital" focuses on the question of emergency unscheduled power blackout Hospital Jihlava, also explains the basic concepts related to this topic and describes the functioning of the hospital equipment. The theoretical part consists of several chapters which provide basic information about electricity, the electricity grid, power plants, transmission and distribution systems, principles and functioning of the hospital. There is clear description of the Maslow's pyramid of human needs, in this part is also explanation of the term "blackout" and the incidence of several serious blackouts of electricity in the Czech Republic and worldwide, experience with them and their impact on human society. The practical part is the basic characteristic of Hospital Jihlava, location of alternative sources - diesel power generators, a description of the various sources of electric power, their function and principle of functioning of Hospital Jihlava. The whole research theoretically examined the readiness Hospital Jihlava to power blackout. The basic method of investigation was to collect data that was obtained through a guided interview with the responsible employees, their answers were transcribed into text and then were analyzed risks identified by the method KARS, in order to investigate the size of the impact of the crisis situation on patients. It is assumed that it is sufficiently adequate protection against failure of the power system, that could at power interruptions, endanger patients, staff, expensive diagnostic and surgical instruments actually overall functioning of this important institution. Based on the investigation was identified the need to inform the public, staff, patients and top management. Technicians may well ensure the functioning of important machinery and equipment. Equally important is understanding of this issue by medical staff to be well versed in an emergency situation quickly. The behavior and conduct of staff could help manage the situation without major problems and reduce imminent risk of impact on patiens and expensive instrumentation to a minimum. Also for this purpose could serve the results of this work. The aim of the thesis was to investigate the effects of a power blackout at the Hospital Jihlava on patients and suggest possible measures. The results of the survey show that a sudden power outage Hospital Jihlava presents a serious threat to its functionality, for this reason, in the final part of my thesis are presented the final recommendations, which can not only reduce the risk of impact on patients.
20

Environmentální zdraví osob v důsledku výpadku elektrické energie / Environmental health of people as a result of a power outage

JIRÁŇOVÁ, Petra January 2018 (has links)
Nowadays none of us can imagine world without electricity, we need it in everyday life. Perhaps that is why we can't imagine what could happen in case of power failure on larger area of Czech Republic. What else consequences it could cause, in particular on our health, or lives. Thesis focuses on finding, if large power failure impacts our lives or health. Immediate impact after beginning of blackout we already know, but we need to find out, what consequences could come after several days. The purpose of thesis is to find out environmental impact of power failure on health of population. I decided to research in section of drinking water and wastewater, from view of epidemiologist of regional hospital, doctor from KHS Český Krumlov and clerk of crisis department ORP Český Krumlov. To meet the goal of thesis, there was created analysis of research of several power outs, which happened in various states all over the world. Other part presents interviews with experts and evaluation of their answers, by which reached the goal of thesis. The research question, of an impact of large power failure on health and lives, we could answer, that the most serious impact it would have on people who had to be accommodated in spare accommodation facilities. They would be endangered by alimentary, infection and respiratory diseases. Concerning drinking water and wastewater, the large impact on human health wasn't detected.

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