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Denna systematiska litteraturstudie handlar om definitioner av psykopatiska drag hos barn och ungdomar. Denna studie ämnar redovisa hur psykopatiska drag kan yttra sig, om de är knutna till arv eller miljö samt huruvida dessa personlighetsdrag hos barn och ungdomar är tillfälliga eller bestående. Riskbedömningsinstrument som PCL: YV och APSD samt aktuell forskning kring genetiska och sociala förklaringar till psykopatiska drag hos barn och ungdomar är inkluderat. Psykopatiska drag hos barn och ungdomar är ett kontroversiellt ämne. Studiens huvudsakliga frågeställning är; kan psykopati identifieras hos barn och ungdomar? / This systematic literature study discusses definitions of psychopathic traits in children and adolescents. We aim to clarify how psychopathic traits are expressed, if they are connected to inheritance or upbringing as well as if these personality traits are temporary or persistent. Risk assessments such as PCL: YV and APSD and current research about possible genetic and social explanations to psychopathic traits in childhood and adolescence is included. Psychopathic traits in childhood is a controversial subject. Our main questions is; can psychopathy be identified in children and adolescents?

A method was developed to assist with the understanding of a unique configuration and investigate some of its stability and control attributes. Oblique wing aircraft concepts are a design option that is well understood, but has yet to be used in a production aircraft. Risk involved in choosing such a design can be averted through additional knowledge early in the concept evaluation phase. Analysis tools commonly used in early conceptual level analysis were evaluated for applicability to a non-standard aircraft design such as an oblique flying wing. Many tools used in early analyses make assumptions that are incompatible with the slewed wing configuration of the vehicle. Using a simplified set of tools, an investigation of a unique configuration was done as well as showing that the aircraft could be trimmed at given conditions. Wave drag was investigated to determine benefits for an oblique flying wing. This form of drag was reduced by the distribution of volume afforded by the slewing of the aircraft's wing. Once a reasonable concept was developed, aerodynamic conditions were investigated for static stability of the aircraft. Longitudinal and lateral trim were established simultaneously due to its asymmetric nature. / Master of Science

A direct, simple, and accurate way to measure skin friction by oil-film laser interferometry has been developed by various researchers. Equations and methods were developed to correct measurement errors arising from three-dimensional effects and pressure gradients. The oil-film, dual-beam laser interferometer was constructed to measure the skin friction around a wing-body junction in a three-dimensional, turbulent boundary layer with pressure gradients. The flow was dominated by the formation of a junction vortex generated at the nose of the wing-body. The oil-film skin friction results were compared with previous skin-friction measurements for the flow obtained by hot-wire measurements. The skin friction values agreed within approximately 8% between the two methods. The effects and benefits of scanning laser interferometry and alternative beam directions were investigated and discussed. The effect of dirt contamination on the data is also discussed. Methods to improve the data quality are presented. / Master of Science

In this work the effect of elasticity on turbulent drag reduction due to polymers is investigated using a hybrid Direct Numerical Simulation (D.N.S) and Langevin dynamics approach. Simulations are run at a friction Reynolds number of Re_&tau = 560 for 960.000 dumbbells with Deborah numbers of De = 0, De = 1, and De = 10. The conclusions are that it is possible to simulate a drag reduced flow using hybrid D.N.S. with Langevin dynamics, that polymers, like other occurrences of drag reduction, reduce drag through streak stabilization, and that the essential property of polymers and fibers in having a drag reducing effect is their ability to exert a torqueon the solvent when they orientate in the boundary layer of the turbulent flow.

Materials with resonant features can have a rapidly changing refractive index spectrally or temporally that gives rise to a changing group index. Depending on the wavelength of the input light, this light can see regimes of normal or anomalous dispersion. Within these regions, the group index can become large, depending on the optical effect used, and give rise to slow or fast light effects. This thesis covers two platforms that exhibit the use of slow and fast light. Slow and fast light are used to manipulate and enhance other optical effects in question. As the focus of this thesis, we examine a rotating ruby rod and spaceplates based on multilayer stacks, both considered as slow- and fast-light media. Light propagation through each platform is modelled and simulated to compare to the experiment. The simulation results for both platforms match well with the measured experimental effects and show the feasibility and utility of slow or fast light to manipulate or enhance optical effects. We simulate light propagation in a rotating ruby rod as a rotating, anisotropic medium with thermal nonlinearity using generalized nonlinear Schrodinger equations, modelling the interplay of many optical effects, including nonlinear refraction, birefringence, and a nonlinear group index. The results are fit to experimentally measured results, revealing two key relationships: The photon drag effect can have a nonlinear component that is dependent on the motion of the medium, and the temporal dynamics of the moving birefringent nonlinear medium create distorted figure-eight-like transverse trajectories at the output. We observe light propagation through a rotating ruby rod where the light is subject to drag. Light drag is often negligible due to the linear refractive index but can be enhanced by slow or fast light, i.e., a large group index. We find that the nonlinear refractive index can also play a crucial role in the propagation of light in moving media and results in a beam deflection. An experiment is performed on the crystal that exhibits a very large negative group index and a positive nonlinear refractive index. The negative group index drags the light opposite to the motion of the medium. However, the positive nonlinear refractive index deflects the beam along with the motion of the medium and hinders the observation of the negative drag effect. Therefore, it is deemed necessary to measure not only the transverse shift of the beam but also its output angle to discriminate the light-drag effect from beam deflection. This work could be applied to dynamic control of light trajectories, for example, beam steering and velocimetry. For the following two chapters, we will focus on a different slow-light platform. This platform focuses on optics that we developed and tested that compress the amount of free-space propagation using multilayered stacks of thin films known as spaceplates. We design and characterize four multilayer stack-based spaceplates based on two design philosophies: coupled resonators and gradient descent. Using the transfer-matrix method, we simulate and extract the angular and wavelength dependence of the transmission phase and transmittance to extract and predict compression factors for each device. A brief theoretical investigation is developed to predict resonance positions, spacing, and bandwidth. We measure the transverse walk-off to extract the compression factor of four multilayer stack-based spaceplates as a function of angle and wavelength. One of the devices was found to have a compression factor of $R=176\pm14$, more than ten times larger than previous experimental records. We increased the numerical aperture of one of the devices by ten times, and we still observed a compression factor of $R=30\pm3$, two times larger than the most recent experimental measurements. We also measured focal shifts up to 800 microns, more than 40 times the device size, typically 10-12 microns thick. The multilayer stack-based spaceplates we studied here show great promise for ultrathin flat optical systems that can easily be integrated into a modern-day imaging system.

The objective of this research was to investigate the affects of various generator plate size, D/d ratio, stroke frequency and slurry concentration, for a plate type vortex ring mixer, on the drag force and power consumption. In this case CaCO3 aqueous slurry was used for the investigation. The generator plate was driven using an AC induction motor with gear type speed reducer which was controlled using a frequency inverter and a mechanism for converting rotational into translational motion. This drive system resulted in sinusoidal motion of the generator plate. The applied force, the displacement of the generator plate and the input power were measured using measurement cell developed for this purpose. The viscosity was also measured. The data were analyzed, organized and presented using appropriate graphs. The force measurement data showed that drag force was mainly affected by the size of generator plate and its oscillating frequency. Larger generator plates had greater drag force acting on them and, therefore, required more power for running. Oscillating frequency had similar effect on drag force and power consumption. However, tested CaCO3 slurry concentrations showed to have no significant affect on these two parameters. Drag force results obtained during this study are considered to be reasonably representative, while power consumption data, although representative for this system, will probably be different for different drive systems employed. / Thesis / Master of Engineering (ME)

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