Many research groups have conducted the investigation into terahertz technology for various applications over the last decade. THz imaging for security screening has been one of the most important applications because of its superior performance of high resolution and not health hazardous. Due to increasing security requirements, it is desirable to devise a high-speed imaging system with high image quality for concealed weapon detection. Therefore, this thesis presents my research into a low-cost and fast THz imaging system for security application. This research has made a number of contributes to THz imaging, such as proposing the beam scanning imaging approach to reduce the scanning time; developing the simulation method of the scanned imaging system; investigating new reconstruction algorithms; studying the optimal spatial sampling criterion; and verifying the beam scanning scheme in experiment. Firstly, the beam scanning scheme is proposed and evaluated in both simulation and experiment, compared to the widely applied raster scanning scheme. A better mechanic rotation structure is developed to reduce the scanning time consumed and realise a more compact system. Then, a rotary Dragonian multi-reflector antenna subsystem, comprising two rotated reflectors is designed to form a similar synthetic aperture being realised in the raster scanned scheme. Thirdly, the simulation of the THz scanning imaging system is achieved by employing Physical Optics algorithm. The transposed convolution and partial inverse convolution reconstruction algorithms are investigated to speed up the image re-construction. Finally, two THz imaging systems based on the raster and beam scanning schemes are assessed and compared in the experiments. The back-propagation, transposed convolution and partial inverse convolution algorithms are applied in these experiments to reconstruct the images. The proposed beam scanning scheme can be further explored together with antenna arrays to provide a compact, fast and low-cost THz imaging system in the future.

The physical properties of visible light and its interaction with matter create obstructions the human eye cannot explore. High energy radiation has been used as an alternative to visible light to penetrate these concealed regions and reveal their contents. However, traditional imaging techniques require a two-sided apparatus with a radiation source and a detector on opposite sides of the concealed object. One-sided imaging of concealed objects is made possible by a technique called backscatter imaging, utilizing high energy radiation. However, the signal produced by backscatter imaging is inherently weak, which makes in- terpretation di cult. One of the most promising techniques for recovering the weak signal is the coding and decoding provided by Coded Aperture Imaging (CAI). The purpose of this study was to create and test a coded aperture imaging system using backscattered x-rays. This would enable one-sided imaging of concealed objects and demonstrate whether a portable imaging system was feasible. The results obtained from conducting a computer simulation, visi- ble light experiments, and x-ray experiments proved that the process works, however, the x-ray ux levels required were too high for a portable system, based upon the current equipment available at UOIT. / UOIT

Concealing information, one of the many forms of deception, is a pervasive phenomenon as it is present in virtually every facet of interpersonal communication. In some cases, information concealment can have profound implications (e.g., insider threats in organizations, security screening at the border, and criminal interviews). New technologies are under development to aid in identifying concealed information, however, additional research is needed in three key areas to increase the feasibility of using these technologies in real-world credibility assessment contexts. First, research is needed to investigate the accuracy of new credibility assessment technologies relative to existing deception-detection systems. Demonstrating that new technologies meet or exceed detection accuracies of existing systems (e.g., the polygraph) is critical. Second, research is needed to determine if a targetless Concealed Information Test (CIT) is feasible. Existing CIT research supports the presence of main effect differences between persons concealing information and the control group. These behaviors may permit the detection of concealed information without the use of customized sets of stimuli. Eliminating the need to create customized sets of stimuli for each examinee would drastically increase the ease with which an automated system can be used to conduct a CIT. Finally, research is needed to illuminate various elements of the human-computer interaction that occurs during automated credibility assessments. This is a new domain of human-computer interaction as system users in this context are not instigating the interaction, and in many cases, they may be seeking to limit the effectiveness of the system. Before novel systems designed to conduct credibility assessments can be adopted, further research is needed to illuminate how users perceive, respond to, and strategically manage their behaviors when interacting with systems of this nature. This dissertation contains the results of a research program designed to address each of these areas. First, an experiment was designed to investigate the accuracy rates of two promising noncontact measures of concealed information (oculometrics and vocalics) relative to electrodermal activity (EDA). Second, an experiment was designed to evaluate the feasibility of using a targetless CIT to elicit main effect differences between concealers and the control group to identify concealed information. And third, a thorough analysis of examinees' general perceptions, self-reported stress and arousal, perceived effort and performance, and use of countermeasures within the context of an automated credibility assessment interview was conducted. This research effort has yielded the following findings. First, eye tracking and vocalics can be used to identify significant differences in the behaviors and physiology of examinees concealing information, however, the accuracy with which truth tellers and information concealers can be classified remains impractical for an applied setting. Second, there are main effect differences between persons concealing information and telling the truth, however, the use of countermeasures may limit the accuracy with which concealers can be identified. Finally, the presence of concealed information and the use of crime-relevant questions alter how examinees perceive and react to a system designed to identify concealed information. The limitations of this research, as well as directions for future research, are discussed.

There is a rich literature on how people tell lies and detect them in others, but the underlying mechanisms are still poorly understood. The first aim of this thesis was to elucidate key cognitive and neural processes underlying cued (i.e., instructed) and uncued lies. The second aim, based on recent research suggesting a link between dishonesty and creativity, was to determine whether creative cognition contributes to deceptive communication. In a first behavioural study, performance on generating and detecting lies was measured in a socially interactive setting involving cued and uncued lies. Results of a multiple regression analysis showed that creativity predicted lying generation ability: more creative individuals were better liars than less creative people. In contrast, the ability to detect lies showed no association with creativity measures, suggesting that generating and detecting lies are distinct abilities. A second event-related potential (ERP) study investigated the neural mechanisms underlying the generation of uncued lies using a novel bluffing paradigm where participants lied at will. Results showed no stimulus-locked differences between uncued lies and truths, suggesting that decision processes leading to both required comparable cognitive resources. Once the uncued decision has been made, it requires strategic monitoring to keep track of the responses in order to maximize the gains regardless of whether the outcome is a lie or the truth as indexed by no response-locked differences between uncued lies and truths. Finally, parallel functional magnetic resonance imaging (fMRI) and ERP studies were conducted to determine the role of creativity in countermeasure use in a concealed information paradigm requiring cued lying. Results showed that countermeasures degraded the neural signatures of deception and more so for more creative individuals. This work advances understanding of the cognitive and neural mechanisms underlying deception as well as their dependence on individual differences in creative cognition.

This research explores the experiences and attitudes of nine full-time students with disabilities at Virginia Tech who choose to conceal their identity as individuals with disabilities in various contexts. The definition of disability is expanded to include those individuals who perceive themselves to be disabled, with or without meeting diagnostic or legal criteria, since many of those who conceal their differences may choose not to pursue such forms of official classification and identification. In a series of interviews, participants provide insight into their experiences, labels and discourse that have shaped those experiences, and outcomes of identification as individuals with disabilities. A variety of themes emerging from the interviews, under the categories of experiences, labels and discourse, and outcomes of disability, are analyzed and discussed. This research aims to explore and develop a greater understanding of these individuals and what their stories have to offer through an emic perspective. / Ph. D.

Currently, techniques used to determine whether or not there is a concealed fire in an inaccessible area of a coal mine are not definitive. Inaccessible areas of coal mines include: 1. A mined-out area, such as a long-wall gob. 2. A mine area, or entire mine, that has been sealed to extinguish a fire. 3. The interior of pillars in a mine. 4. Abandoned mines. Mined-out areas — gobs — are particularly problematic. The standard practice is to obtain measurements for certain gas concentrations from an inaccessible area, and to apply certain rules to the obtained concentrations in order to try to decipher whether or not there is a fire in the area. Unfortunately, none of the gas measurements, and the associated rules that are applied, are free of potential problems. Therefore, there is always some degree of uncertainty in any decision that is based on the current methods. A more definitive method of determining whether or not a concealed fire exists would be valuable; perhaps avoiding unnecessary exposure of miners to risks, and unnecessary exposure of mining companies to economic loss. This study details the inadequacies of the current methods for determining the presence of a fire in an inaccessible area of a coal mine, and proposes two novel methods for overcoming the current inadequacies. The first method that was studied involves looking for the presence of the radioisotope carbon-fourteen in the carbon monoxide in the return airways of coal mines. For the vast majority of coal mines, if there is no fire anywhere in the coal mine, carbon monoxide should not have any carbon-fourteen in it. If there is a fire, the carbon monoxide should have carbon-fourteen in it. This method is based on the Boudouard Reaction, which documents a reaction between carbon, carbon monoxide, and carbon dioxide that only occurs at temperatures that only occur with a fire. Because of the very small amounts of carbon-fourteen in carbon dioxide in the atmosphere, and the small amount of carbon monoxide usually present in a coal mine atmosphere, there does not appear to be any way, currently, to implement this method. Instrumentation that may allow implementation of this method, in the future, is discussed. The second method, that was studied, involves introducing a select, gaseous, organic compound into an inaccessible area; and then using a gas chromatograph to test for the presence of definitive fire decomposition products of the initial organic compound in the atmosphere that is exiting the inaccessible area. Laboratory tests, conducted as part of this study, established the concept of this novel method of using select, organic compounds for definitively determining whether or not a concealed fire exists in an inaccessible part of a coal mine. Based on an initial screening of 5 different compounds, two compounds have been selected for use as 'fire indicator gases' with the acronym of 'FIGs.' These two compounds are: 1. C6-Perfluoroketone (CF3CF2C(=O)CF(CF3)2 ) 2. 1,1 Difluoroethane (CH3CHF2) This study provides suggestions as to how to look for other potential FIGs, and how to improve the testing of potential FIGs. Examples of all four of the types of inaccessible areas listed above are discussed, particularly from the viewpoint of how FIGs could be utilized in each case, and how FIGs could provide better information in each case. In addition, as a by-product of the experiments conducted for this work, this study identifies at least six gases that might be used simultaneously as tracer gases for complex ventilation studies in a mine, or elsewhere. / Ph. D.

Detta projekt gick ut på att undersöka möjligheterna för integrerade gångjärn till köksluckor samt att försöka ta fram en möjlig lösning. Under projektets inledande fas faktainsamlingen undersöktes dagens lösningar, diverse material och tillverkningsmetoder samt tribologi. Kundkrav identifierades som sedan låg till grun-den för funktionsanalysen, dessa funktioner rangordnades. De tre högst prioriterade egenskaperna var dold öppning, monteringsmöjlighet och justeringsmöjlighet. Dessa rangordnade funktionerna användes till idégenereringen och olika koncept togs fram, bland dessa koncept valdes ett som sedan bearbetades i flera iterationer med hjälp av CAD-program och prototyping till ett förfinat koncept som blev projektets resultat. / This project intended purpose was to examine the possibilities with integrated hinges for kitchen cabinet doors and try to develop a plausible solution. The project started with benchmarking and thereafter researching different materials, manufacturing methods and lubricants. Customer demands was also identified and these demands where used for the function analysis. These functions where the backbone of the morphological matrix used in the concept generating process that led to sex different concept ideas, one concept idea was chosen and developed in to one nearly finished product.

This thesis demonstrates the further development of an ultra-wideband (UWB) pulse generator and of an UWB antenna. Custom prototypes of these devices were initially developed for an ongoing research project. The project topic is a compact and portable concealed weapons detection (CWD) radar system to find objects such as firearms, knives, and grenades hidden on persons as they pass by. The system uses the UWB pulse generator as a transmitter, while the UWB antenna radiates the pulse and receives the corresponding backscatter from targets and other objects. Initial device prototypes do not perform adequately according to project specifications. A key specification is of adequate operation over the entire 0.5 GHz to 5 GHz frequency band, where adequate operation is defined distinctly for the antenna and pulse generator. In this work, empirical investigations of both devices are performed using techniques such as simulation, fabrication, and measurement. Through these investigations, the designs of the devices have been incrementally modified. Measured performance data suggest that the research has yielded designs with substantially improved bandwidth as a result. Bandwidth increases from 3.31 GHz to 4.36 GHz (31.7%) for the pulse generator and from 0.46 GHz to 4.98 GHz (983%) for the antenna are demonstrated. Future work is needed to establish the effects of fabrication tolerance, component tolerance, and human error on the variation of the observed device performance. / Thesis / Master of Applied Science (MASc) / This thesis is about the improvement of a radio antenna and a transmitter. These are ultimately intended as components in a system for detecting weapons (such as firearms, knives, etc.) concealed within the clothing or bags of nearby persons. The detection happens by transmitting specific radio signals which interact harmlessly with a person being scanned, and then are received back by the system. This is a form of radio detection and ranging (RADAR). The research on these devices has consisted of computer simulations and real-life measurements. As a result, it appears that the transmitter and radio antenna have been improved to be more suitable for the desired application than they were originally.

Determination of Parenthood The topic of my thesis is Determination of parenthood. The reason why I chose this topic is because it combines legal, historical, social and ethical aspects. Goal of my thesis is to analyse legal institute and raise awareness about its problems. The thesis is concerned with determination of maternity, determination of paternity and denying of paternity. Diploma thesis is divided into five chapters. First chapter is Introduction, in which I determine the extent of the thesis. Second chapter deals with historical development of legal regulation of determination of parenthood. This chapter comprises of three subchapters. First is concerned with determination of parenthood in ancient Rome. Second explains determination of parenthood in ABGB. Third explains the Czech legal regulation between 1948 and 2014. Third chapter is about contemporary legal regulation. Chapter is divided in three subchapters. First deals with determination of maternity. Second deals with determination of paternity. Third deals with denying of paternity. Fourth chapter reports on decisions of European Court of Human Rights. It outlines concrete cases a tries to summarise, how the court decides in question of determination of parenthood. Last chapter summarises the whole thesis with conclusion that...

Establishing parentage The subject of this master thesis is the issue of establishing parentage. The thesis targets areas of establishing parenthood, issues of three legal presumptions and last but not least, parenthood denial. The question of establishing maternity is examined mainly from perspectives including surrogate maternity, assisted reproduction method and secret and anonymous delivery. All matters are reviewed based on the valid amendment to Act No. 89/2012 Coll., the Civil Code that has come into effect on 1.1.2014. The goal of the thesis is it to introduce, describe and analyze the new amendment to the Family Act. Further, it aims to compare individual institutions with respect to changes made to the Family Act in the past and those made as a part of the new amendment. The thesis consists of eight key chapters. The initial chapter targets relationships among parents and their children, protection of children's legal rights as well as a child's right to know its biological origin. Following, the second and the third chapters concentrate in depth on legislation of the paternity establishment per se. While the second chapter covers the historical development of the legislation from the ancient Rome era until present, the latter chapter intends to introduce the legislation from domestic,...