Dissertations / Theses: 'Objective- and subjective assessment'

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Statham, Andrew. "Subjective and objective assessment of tennis racket performance play." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/4080.

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Assessment of wielded implement performance is important to a variety of human endeavours and often critical to success in a sports context, particularly so in the game of tennis. Tennis racket design and manufacture is a multimillion business involving 10 major international companies. Tennis participation is currently estimated at around 60 million individuals worldwide. Thus the importance of optimum racket performance to maximise competitive advantage and minimise the risks of injury is clear. This thesis presents work to enable advances in tennis racket performance with respect to player feel perception, measurement of physical phenomena and the correlation of these aspects within real play contexts. To investigate feel perception a methodology was adapted from the existing literature. Interview testing was conducted to elicit a comprehensive range of tennis specific vocabulary. The end goal was to create a perception relationship map or 'feel map'. The inductive analysis was used to link all the related clustered themes identified from the vocabulary to sub and base themes describing the relationship. Further analysis introduced higher level general dimensions that unified common base themes. The resulting feel maps were created from both English and German sample groups, with a view to subsequent comparison. To complete the map and broaden its application a wide scale questionnaire was distributed to a tennis playing population. The responses provided data indicating percentile use of selected vocabulary within the tennis community and the relative importance players associate with assorted perception groups. Visual representations of the data were introduced to the map for quick and easy use and an associated lexicon compiled to provide a reference for more detailed information. The feel maps and lexicon provide users with a versatile tool in the form of a 'perception relationship model'. The map itself can act as an overall research guide for future work in the field. The addition of percentile use and relative importance data mean the map can be used to create more informed and subtle player test questionnaires or as a design aid, with interdependency links indicating which additional factors should be considered or exploited for their influence on the characteristic areas in question. Interestingly the general dimensions of highest relative importance were sound and grip respectively. This may be due to the basic level of interaction between player and racket which ultimately has to be perceived either through the grip or from the sound. A perception test questionnaire was also created with the use of the feel map and later used to study the correlation between objective and subjective measures. To best attain objective measures from the racket an innovative instrumentation system was created. Two alternative systems were designed and tested, the first based on wired instrumentation and data capture the second based on wireless technologies as these became available. Both systems were required to take measures of grip pressure and acceleration with 6 degrees of freedom. The first system utilised uniaxial accelerometers mounted on an aluminium bracket, and a triaxial accelerometer inserted inside the butt of the racket arranged to allow measurement and calculation of acceleration from the required 6 degrees of freedom. The system could be adapted to include either TekScan multi-cell full grip coverage force measurement, or 2 single point higher sample rate single cell grip force sensors. All data was fed via 15 m of cable to data acquisition systems. This restricted the participants' freedom of movement and encumbered the racket and thus the systems application, making it unsuitable for extensive perception or fatigue testing. The second system utilised a compact data logger with an integrated on board tri-axial accelerometer small enough to be mounted within the racket handle. A revised mount overcame the need for the aluminium throat bracket, moving the uniaxial accelerometers into a bulbous addition to the butt of the racket. The system was capable of capturing 8 channels simultaneously which allowed for the 6 accelerometers and two single cell grip force sensors to be located under the grip. The system was more difficult to adapt and maintain than the wired system, but improved freedom and reduced added weight to the racket made the system far more suitable for the planned perception and fatigue testing. Fatigue testing conducted with the wireless device investigated the effect of full body fatigue on players' performance by monitoring the resultant effects in the racket. The protocol was based on the multistage fitness test, designed to progressively increase in difficulty until volitional fatigue. Heart rate data indicated that the protocol was successful in fatiguing the participants to a point at or near their VO2max. Unfortunately, with the wireless system in its early stages of development, the device failed mid way through testing. The limited data set that was collected indicated that technique was affected by fatigue. Further research is required to confirm this finding and to make comparisons between racket types during the fatiguing process. The wireless device was adapted to make it more durable and reliable before the planned perception testing was conducted. A protocol was developed to investigate the affect of changing racket moment of inertia on player perception and physical measures. The test questionnaire developed from the feel map was used to evaluate player perception ratings of various elements of racket feel, and the wireless instrumentation system was used as part of methodology designed to compile a set of comparable physical data. A detailed analysis of the results revealed that there was some evidence of correlation between the perceptions of power, balance, flexibility and control and the moment of inertia of the racket. In a design optimisation context, however, more definitive correlations would be more useful. These would be expected to be found with future testing utilising a wider range of racket properties. The research proves to a large extent the original hypothesis that through the use of non invasive instrumentation and improved player perception elicitation techniques it is possible to substantially and usefully improve the objective and subjective assessment of tennis racket performance in play to enable investigation of better design characteristics and fatigue related injury phenomena.

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Freeman, Jonathan. "Subjective and objective approaches to the assessment of presence." Thesis, University of Essex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298879.

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Skildheim, Kim Daniel. "Subjective and Objective Crosstalk Assessment Methodologies for Auto-stereoscopic Displays." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18913.

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Stereoscopic perception is achievable when the observer sees a scene from a slightly different angle. Auto-stereoscopic displays utilize several separate views to achieve this without using any special glasses. Crosstalk is an undesired effect of separating views. It is one of the most annoying artefacts occurring in an auto-stereoscopic display. This experiment has two parts. The first part proposes a subjective assessment methodology for characterizing crosstalk in an auto-stereoscopic display, without restriction of subjects’ viewing behaviour. The intention was to create an inexpensive method. The measurement was performed by using a Kinect prime sensor as a head tracking system combined with subjective score evaluation to get a data plot of the perceived crosstalk. The crosstalk varies in line with image content, disparity and viewing position. The result is a data plot that approaches a periodically pattern, which is consistent with the characteristics of an auto-stereoscopic display. The result is not perfect since there are many sources of errors occurring. These errors can be improved with better head tracking, an improved movement system, post processing of data, more data and removal of outliers.The second part proposes methods for extracting subjective values based on interpolated plots and creating objective crosstalk influenced pictures which correlate with the subjective data. The best extraction method was to combine an adapted sine regression curve with a linear interpolation. This interpolation followed the subjective values in a parallel slice plot at 3.592 m from the screen. The interpolation was adapted to fit a derived model as best as possible to achieve a good correlation. Objective crosstalk pictures were created, where the amount of crosstalk was determined by the neighbouring view that influenced the current view the most. The correlation was based on the relationship between the SSIM value from the created crosstalk picture and the extracted subjective value. The total correlation of the pictures together were 0,8249, where the picture with the highest correlation had 0,9561. This method is quite good for pictures that have a maximum disparity grade below 38 pixels. The overall result is good and it is also a measure of quality for the subjective test. This result can be improved by increasing the complexity of how the objective crosstalk pictures are created by adding more views into account or try another method to create crosstalk. Improved extraction of subjective values will also be beneficial in terms of improving the correlation even more.

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Su, He Zhicheng Xuxin. "Links between Subjective Assessments and Objective Metrics for Steering." Thesis, KTH, Fordonsdynamik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101925.

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The characteristics of vehicle steering perception are decisive factors concerning vehicle safety and overall pleasure behind the wheel. It is a challenge for vehicle manufacturers to achieve these features and qualities, because usually vehicle tuning almost only relies on subjective evaluation of test drivers, which is costly and time consuming. In order to optimize suspension design and develop a tool that can be used to evaluate steering with objective metrics instead of subjective assessment, links between them must be confirmed. In this master thesis, both objective and subjective testing data of over 20 vehicles across four different segments are introduced in linear and nonlinear analysis. Linear regression analysis is applied to investigate simply positive or negative correlation between a pair of subjective-objective parameters. However, even if certain linear correlations are obtained, it is still hard to define the optimal value for objective metrics. Considering that the general shape of a correlation function can reveal which objective range give higher subjective rating, it is possible to define these preferred ranges with Neural Network (NN). The best data available is adopted from three drivers who tested 15 sedans, and some interesting results are found. The initial results demonstrate that NN is a powerful tool to uncover and graphically illustrate the links between objective metrics and subjective assessments, i.e., the specific range leading to better steering feel. Given a larger sample size, more reliable and optimal links can be defined by following the same method. These confirmed links would enable vehicle dynamics engineers to more effectively develop new vehicles with nearly perfect steering feel.

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Luotonen, David, and Markus Hasselström. "Subjective and objective performance assessment : Performance pay at Trelleborg Forsheda AB." Thesis, Jönköping University, JIBS, Business Administration, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-9660.

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The purpose of this thesis is to understand the opinions and potential effects of objective and subjective assessments of performance as a basis for performance pay for blue-collar workers.

The study takes a qualitative approach to find out how and why four companies - Trelleborg Forsheda, Finnveden Powertrain, Isaberg Rapid and Parker Hannifin- work with salaries, incentive system and performance assessment the way they do.

The concept of individual salary is central in this thesis, and individual salary is based on four criteria; capabilities, performance, work demand and formal competence. These can be divided in subjective or objective criteria. Individual salaries also contribute to salary divergence, which in many studies have indicated higher performance. Important to remember is that it has to exist a purpose to salary divergence and how salary is diverged in the company is related to the goals and strategy of the company. If the company chooses to have performance based salaries- which is salary divergence- another question arise; what is good performance?

In organizations that have performance salaries, a group or an individual (often the middle manager) have to decide if a certain group of personnel performs good or bad. This can mainly be done in two different ways; objective performance assessment or subjective performance assessment. Objective performance assessment is based on numerical calculation of measures, which will form the basis for rewarding employees using a salary system that reward performance. Subjective performance measurements are based on judgment. Instead of relying on numerical calculations, one evaluates if the results reflect good or bad performance.

For both methods it is essential that the personnel feels that the salaries are fair, and that the salary system is clear and easy to understand. Something else that is important to understand is that employer and employee have different views in what is a fair salary.

Objective assessments are based on numerical calculations of measures, and one important property such measures have is that they don’t leave any room for excuses. Research indicate that performance pay has important motivation enhancing effects, but the profitability doesn’t always benefit from it. When monitoring costs are high, or product quality or long term thinking is required, hourly wages may be preferable. Tasks which are measured, will naturally be prioritized by the organization. This means that the choice of measures is very important. The amount of measures mustn’t be too high, and they have to be carefully considered. Subjective assessments are the opposite to objective ones. The advantages with subjective performance assessments are, among other things, that additional information which have surfaced during the period of measurements can be taken into consideration, errors in the measurement process can be corrected and unlucky circumstances can be dealt with. However, problems exist in unfair assessments, which are based on prejudice.

Findings in this report shows that profitable companies have large differences in their salary systems. This is also supported by other research. The company Isaberg Rapid AB only uses objective criteria, focused on simplicity and group rewards. Finnveden Powertrain on the other hand, has a system focused on individuals and subjective assessments. Some conclusions could be drawn; one of the most important being that connections between the type of activities and the salary system is positive, and that salary systems have to be updated and revised continuously.

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Dalasari, Venkata Gopi Krishna, and Sri Krishna Jayanty. "Low Light Video Enhancement along with Objective and Subjective Quality Assessment." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13500.

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Enhancing low light videos has been quite a challenge over the years. A video taken in low light always has the issues of low dynamic range and high noise. This master thesis presents contribution within the field of low light video enhancement. Three models are proposed with different tone mapping algorithms for extremely low light low quality video enhancement. For temporal noise removal, a motion compensated kalman structure is presented. Dynamic range of the low light video is stretched using three different methods. In Model 1, dynamic range is increased by adjustment of RGB histograms using gamma correction with a modified version of adaptive clipping thresholds. In Model 2, a shape preserving dynamic range stretch of the RGB histogram is applied using SMQT. In Model 3, contrast enhancement is done using CLAHE. In the final stage, the residual noise is removed using an efficient NLM. The performance of the models are compared on various Objective VQA metrics like NIQE, GCF and SSIM. To evaluate the actual performance of the models subjective tests are conducted, due to the large number of applications that target humans as the end user of the video.The performance of the three models are compared for a total of ten real time input videos taken in extremely low light environment. A total of 25 human observers subjectively evaluated the performance of the three models based on the parameters: contrast, visibility, visually pleasing, amount of noise and overall quality. A detailed statistical evaluation of the relative performance of the three models is also provided.

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Santos, Magalhães André. "Subjective and objective assessment of physically active people with knee injury." Thesis, University of Kent, 2016. https://kar.kent.ac.uk/60066/.

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Knee injuries are highly prevalent in physically active individuals and are frequently associated with sport participation. Independently of the nature of the injury, subjective and objective clinical measures are used to assess, monitor and evaluate treatment outcomes in this population. To be clinically meaningful, these outcome measures should be relevant to the condition, the anatomical area, the individual or population, and importantly, possess adequate psychometric properties. Despite a high prevalence of knee injuries, there are several aspects of the subjective and objective knee evaluation in physically active individuals that remain unclear or have not been considered in previous research. The main aim of the present thesis was to fill some of the gaps identified in the literature regarding both subjective and objective knee measures in physically active individuals. Therefore, this thesis was divided into two distinct parts. The first part looked at the patient-reported outcome (PRO) measures of the knee and physical activity, and consisted of two studies. The first study was a systematic review conducted to explore the PRO measures that are commonly used in the evaluation of physical activity and return to sport following autologous chondrocyte implantation (ACI). Aiming as well, to provide a critical analysis of these instruments from a rehabilitative perspective. This review revealed not only the heterogeneity in the selection, but also in the timing and reporting of patient-reported activity scoring instruments following ACI, which makes a systematic comparison difficult and introduces bias into the interpretation of these outcomes. Another important finding of this review, was that the instruments currently used to evaluate postoperative outcomes in an articular cartilage repair population do not always fulfil the rehabilitative needs of physically active individuals. The second study was conducted in recreational marathon runners and aimed to provide normative values for a widely used knee specific PRO measure in athletes with knee injury, the Knee Injury Osteoarthritis Outcome Score (KOOS). Alongside the normative KOOS subscales values stratified by age group and history of knee injury that were presented, this study also showed that recent history of knee running-related injury (RRI) has a negative impact on the KOOS scores. In runners with no history of knee RRI, the results observed suggested a lack of interaction between KOOS subscale values and age. Furthermore, the KOOS values seen were substantially higher compared to previously published normative population-based KOOS values. The second part of the present thesis comprised three experimental studies concerning single-leg cycling (SLC) exercise testing, in particular assessing the potential use of the self-paced test (SPT) concept as an objective measure following knee surgery. The first study analysed the reliability of a 5x2 min stages SPT anchored to the rate of perceived exertion (RPE) for SLC exercise testing. This study showed that this test protocol elicits reliable cardiorespiratory and metabolic responses. The second study examined the validity of the SPT protocol used in the previous study, through a concurrent comparison against a conventional fixed power incremental SLC exercise test. This investigation showed that the 5x2 min SPT provides a valid objective means for assessing peak aerobic capacity in SLC exercise testing. Moreover, it may be associated with increased activity enjoyment comparatively to conventional testing. The third and last experimental study investigated the effect of a 10 kg counterweight device (CW10) on cardiorespiratory, metabolic and perceptual responses to SLC exercise testing. The results of this study demonstrated that the CW10 despite eliciting an improvement in the activity enjoyment, did not affect peak cardiorespiratory and metabolic responses to SLC exercise testing. When matched for test duration the SPT elicited higher peak power output and peak oxygen consumption than conventional incremental testing, regardless of the CW10 usage or not. In conclusion, the original work of the present thesis increases the body of knowledge of two distinct, but complementary fields in the subjective and objective knee assessment of physically active individuals. The outcomes provided both on PRO measures and SLC exercise testing, may have impact on the clinical practice of clinicians, sport rehabilitation professionals and researchers.

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Guo, Jinjiang. "Contributions to objective and subjective visual quality assessment of 3d models." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI099.

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Dans le domaine de l’informatique graphique, les données tridimensionnelles, généralement représentées par des maillages triangulaires, sont employées dans une grande variété d’applications (par exemple, le lissage, la compression, le remaillage, la simplification, le rendu, etc.). Cependant, ces procédés introduisent inévitablement des artefacts qui altèrent la qualité visuelle des données 3D rendues. Ainsi, afin de guider perceptuellement les algorithmes de traitement, il y a un besoin croissant d'évaluations subjectives et objectives de la qualité visuelle à la fois performantes et adaptées, pour évaluer et prédire les artefacts visuels. Dans cette thèse, nous présentons d'abord une étude exhaustive sur les différentes sources d'artefacts associés aux données numériques graphiques, ainsi que l’évaluation objective et subjective de la qualité visuelle des artefacts. Ensuite, nous introduisons une nouvelle étude sur la qualité subjective conçue sur la base de l’évaluations de la visibilité locale des artefacts géométriques, dans laquelle il a été demandé à des observateurs de marquer les zones de maillages 3D qui contiennent des distorsions visibles. Les cartes de distorsion visuelle collectées sont utilisées pour illustrer plusieurs fonctionnalités perceptuelles du système visuel humain (HVS), et servent de vérité-terrain pour évaluer les performances des attributs et des mesures géométriques bien connus pour prédire la visibilité locale des distorsions. Notre deuxième étude vise à évaluer la qualité visuelle de modèles 3D texturés, subjectivement et objectivement. Pour atteindre ces objectifs, nous avons introduit 136 modèles traités avec à la fois des distorsions géométriques et de texture, mené une expérience subjective de comparaison par paires, et invité 101 sujets pour évaluer les qualités visuelles des modèles à travers deux protocoles de rendu. Motivés par les opinions subjectives collectées, nous proposons deux mesures de qualité visuelle objective pour les maillages texturés, en se fondant sur les combinaisons optimales des mesures de qualité issues de la géométrie et de la texture. Ces mesures de perception proposées surpassent leurs homologues en termes de corrélation avec le jugement humain
In computer graphics realm, three-dimensional graphical data, generally represented by triangular meshes, have become commonplace, and are deployed in a variety of application processes (e.g., smoothing, compression, remeshing, simplification, rendering, etc.). However, these processes inevitably introduce artifacts, altering the visual quality of the rendered 3D data. Thus, in order to perceptually drive the processing algorithms, there is an increasing need for efficient and effective subjective and objective visual quality assessments to evaluate and predict the visual artifacts. In this thesis, we first present a comprehensive survey on different sources of artifacts in digital graphics, and current objective and subjective visual quality assessments of the artifacts. Then, we introduce a newly designed subjective quality study based on evaluations of the local visibility of geometric artifacts, in which observers were asked to mark areas of 3D meshes that contain noticeable distortions. The collected perceived distortion maps are used to illustrate several perceptual functionalities of the human visual system (HVS), and serve as ground-truth to evaluate the performances of well-known geometric attributes and metrics for predicting the local visibility of distortions. Our second study aims to evaluate the visual quality of texture mapped 3D model subjectively and objectively. To achieve these goals, we introduced 136 processed models with both geometric and texture distortions, conducted a paired-comparison subjective experiment, and invited 101 subjects to evaluate the visual qualities of the models under two rendering protocols. Driven by the collected subjective opinions, we propose two objective visual quality metrics for textured meshes, relying on the optimal combinations of geometry and texture quality measures. These proposed perceptual metrics outperform their counterparts in term of the correlation with the human judgment

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Shahid, Muhammad. "Methods for Objective and Subjective Video Quality Assessment and for Speech Enhancement." Doctoral thesis, Blekinge Tekniska Högskola [bth.se], Faculty of Engineering - Department of Applied Signal Processing, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00603.

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The overwhelming trend of the usage of multimedia services has raised the consumers' awareness about quality. Both service providers and consumers are interested in the delivered level of perceptual quality. The perceptual quality of an original video signal can get degraded due to compression and due to its transmission over a lossy network. Video quality assessment (VQA) has to be performed in order to gauge the level of video quality. Generally, it can be performed by following subjective methods, where a panel of humans judges the quality of video, or by using objective methods, where a computational model yields an estimate of the quality. Objective methods and specifically No-Reference (NR) or Reduced-Reference (RR) methods are preferable because they are practical for implementation in real-time scenarios. This doctoral thesis begins with a review of existing approaches proposed in the area of NR image and video quality assessment. In the review, recently proposed methods of visual quality assessment are classified into three categories. This is followed by the chapters related to the description of studies on the development of NR and RR methods as well as on conducting subjective experiments of VQA. In the case of NR methods, the required features are extracted from the coded bitstream of a video, and in the case of RR methods additional pixel-based information is used. Specifically, NR methods are developed with the help of suitable techniques of regression using artificial neural networks and least-squares support vector machines. Subsequently, in a later study, linear regression techniques are used to elaborate the interpretability of NR and RR models with respect to the selection of perceptually significant features. The presented studies on subjective experiments are performed using laboratory based and crowdsourcing platforms. In the laboratory based experiments, the focus has been on using standardized methods in order to generate datasets that can be used to validate objective methods of VQA. The subjective experiments performed through crowdsourcing relate to the investigation of non-standard methods in order to determine perceptual preference of various adaptation scenarios in the context of adaptive streaming of high-definition videos. Lastly, the use of adaptive gain equalizer in the modulation frequency domain for speech enhancement has been examined. To this end, two methods of demodulating speech signals namely spectral center of gravity carrier estimation and convex optimization have been studied.

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Anani, John Kodjo. "A subjective and objective assessment of sound insulation in newly converted dwellings." Thesis, Open University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316964.

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Fernandes, Andreia Sofia Pires. "" Objective and Subjective Assessment of Qigong Related Effects in Breast Cancer Patients "." Dissertação, Instituto de Ciências Biomédicas Abel Salazar, 2011. http://hdl.handle.net/10216/57089.

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Fernandes, Andreia Sofia Pires. "" Objective and Subjective Assessment of Qigong Related Effects in Breast Cancer Patients "." Master's thesis, Instituto de Ciências Biomédicas Abel Salazar, 2011. http://hdl.handle.net/10216/57089.

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Mounzer, Raid. "Improving simulators’ driving experience through objective metrics and subjective assessments." Thesis, KTH, Fordonsdynamik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-243488.

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As the challenge grows in the vehicle industry, tightening the margins on financial and environmental costs of the vehicle development, computer aided engineering becomes more and more attractive. Extensive work is being invested in creating detailed models that can replicate vehicle behaviour accurately and efficiently. The work in this thesis starts with studying objective and subjective evaluations of vehicles as well as their counterparts in vehicle models and a simulator environment. Then, it continues to locate the weaknesses in the models, and investigate the possible improvements. The first part of the thesis focused on performing a literature study concerning the objective metrics and their use in the vehicle industry, as well as the use of simulators. This served as a foundation for the use of objective metrics in the validation of the CarRealTime models. The tools used in the thesis were also introduced. The work continued with the study of previously collected data concerning vehicle evaluation through subjective assessment and objective metrics, with different anti-roll bar configurations, to build trust in the ability of the drivers in evaluating these criteria. Similar data from the CarRealTime models and the simulator were also studied. The aim was to evaluate the simulator driving experience accuracy through the subjective assessment. The weaknesses of the model were identified, and an improved steering model was introduced, replacing the old lookup tables with a Pfeffer model from CarRealTime combined with the steering assist unit in Simulink. An extensive parameter study was performed to understand the effect of selected parameters on the driving experience. Using the same model, the simulator delays were studied in terms of replicating yaw and lateral movements, and how this can affect the driver’s perception of the driving experience. Finally, the results from the parameter study were used to assign the weight parameters in the optimization objective function where the goal was to study the possibility of improving the accuracy of the driving experience as well as counteracting the effects of simulator delays. The Matlab Optimization Toolkit was used in the process. As a conclusion, it was shown that the subjective assessment together with the objective metrics played a crucial role in identifying model and simulator weaknesses. The parameter study showed promising opportunities in solving the aforementioned issues, with the optimization tool and boundaries needing more elaborate work to reach conclusive results.

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Khaustova, Darya. "Objective assessment of stereoscopic video quality of 3DTV." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S021/document.

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Le niveau d'exigence minimum pour tout système 3D (images stéréoscopiques) est de garantir le confort visuel des utilisateurs. Le confort visuel est un des trois axes perceptuels de la qualité d'expérience (QoE) 3D qui peut être directement lié aux paramètres techniques du système 3D. Par conséquent, le but de cette thèse est de caractériser objectivement l'impact de ces paramètres sur la perception humaine afin de contrôler la qualité stéréoscopique. La première partie de la thèse examine l'intérêt de prendre en compte l'attention visuelle des spectateurs dans la conception d'une mesure objective de qualité 3D. Premièrement, l'attention visuelle en 2D et 3D sont comparées en utilisant des stimuli simples. Les conclusions de cette première expérience sont validées en utilisant des scènes complexes avec des disparités croisées et décroisées. De plus, nous explorons l'impact de l'inconfort visuel causé par des disparités excessives sur l'attention visuelle. La seconde partie de la thèse est dédiée à la conception d'un modèle objectif de QoE pour des vidéos 3D, basé sur les seuils perceptuels humains et le niveau d'acceptabilité. De plus nous explorons la possibilité d'utiliser la modèle proposé comme une nouvelle échelle subjective. Pour la validation de ce modèle, des expériences subjectives sont conduites présentant aux sujets des images stéréoscopiques fixes et animées avec différents niveaux d'asymétrie. La performance est évaluée en comparant des prédictions objectives avec des notes subjectives pour différents niveaux d'asymétrie qui pourraient provoquer un inconfort visuel
The minimum requirement for any 3D (stereoscopic images) system is to guarantee visual comfort of viewers. Visual comfort is one of the three primary perceptual attributes of 3D QoE, which can be linked directly with technical parameters of a 3D system. Therefore, the goal of this thesis is to characterize objectively the impact of these parameters on human perception for stereoscopic quality monitoring. The first part of the thesis investigates whether visual attention of the viewers should be considered when designing an objective 3D quality metrics. First, the visual attention in 2D and 3D is compared using simple test patterns. The conclusions of this first experiment are validated using complex stimuli with crossed and uncrossed disparities. In addition, we explore the impact of visual discomfort caused by excessive disparities on visual attention. The second part of the thesis is dedicated to the design of an objective model of 3D video QoE, which is based on human perceptual thresholds and acceptability level. Additionally we explore the possibility to use the proposed model as a new subjective scale. For the validation of proposed model, subjective experiments with fully controlled still and moving stereoscopic images with different types of view asymmetries are conducted. The performance is evaluated by comparing objective predictions with subjective scores for various levels of view discrepancies which might provoke visual discomfort

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Foley, Jennifer A. "Retrospective and prospective memory in healthy and cognitively impaired older adults : using subjective and objective assessment." Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/2205.

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BACKGROUND: Retrospective and prospective memory deteriorate with age and deteriorate further with the onset of dementia. As previous research has tended to use idiosyncratic and heterogeneous methodologies, it is not known if the deterioration in retrospective or prospective memory is equal or how such deterioration is related to insight into mnemonic performance. DESIGN: The present study used a mixed, cross-sectional design. It examined retrospective and prospective memory in healthy and cognitively impaired older adults using objective and subjective assessment. METHODOLOGY: Twenty healthy and twenty cognitively impaired older adults were assessed. The objective measures were standardised and had high ecological validity, to maximise the assessments’ generalisability to everyday mnemonic functioning. The subjective measure was a standardised assessment of subjective appraisal of retrospective and prospective memory. This subjective assessment was used to gain self-ratings from the healthy and cognitively impaired older adults and, in addition, to gain proxy-ratings from the cognitively impaired older adults’ partners/carers. Participants were also assessed using a measure of general cognitive functioning. RESULTS: Healthy older adults performed significantly better than cognitively impaired older adults on both the retrospective and prospective memory test, although performance in both groups was higher on the prospective memory test than on the retrospective memory test. Neither proxy-ratings, nor overall severity of impairment, were associated with subjective assessment of prospective or retrospective memory. In the healthy older adults, self-rating of memory was not associated with objective memory performance. In the cognitively impaired older adults, however, higher self-ratings of memory were associated with poorer performance on the prospective memory test. DISCUSSION: The results suggested that both healthy and cognitively impaired older adults perform better on prospective memory tasks than retrospective memory tasks, but both types of memory deteriorate with the onset of dementia. Subjective memory appraisal is not related to objective memory performance in healthy older adults, but is negatively associated with prospective memory performance in cognitively impaired older adults. Findings were discussed in relation to previous research, along with a review of the strengths and limitations of the study. Clinical implications and directions for future research are also suggested.

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Juhlin, Magnus. "Assessment of crosswind performance of buses." Doctoral thesis, Stockholm : Skolan för teknikvetenskap, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10382.

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Silk, Eric Edward. "Relationship between Subjective and Objective Measures of Attention in a Clinical Population of Children and Adolescents." Thesis, NSUWorks, 2012. https://nsuworks.nova.edu/cps_stuetd/66.

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Attention problems can pose a serious challenge to the academic progress of children and adolescents. Currently, there are several different assessment methods utilized in the clinical diagnosis of Attention-Deficit/Hyperactivity Disorder (ADHD). Subjective and objective assessment measures purport to be measuring similar constructs of inattention, hyperactivity, and impulsivity. The present study examines the degree of correlation between the constructs of attention problems, hyperactivity/impulsivity, and signal detection between the Conners' Continuous Performance Test II Version 5 (CPT II) and a parent-report measure of attention problems, hyperactivity/impulsivity, aggression, emotional problems, and learning problems in a general clinical population of children and adolescents. This study also measures the correlation between these measures and the Woodcock Johnson III Tests of Cognitive Abilities (WJ-III COG) Auditory Attention subtest. No significant correlations were found among the CPT II errors of omission score or commissions score and attention problems or hyperactivity/impulsivity. No significant correlations were found among attention problems or hyperactivity/impulsivity and CPT II Reaction Time (RT), variability, or attentiveness. No significant correlations were found among the CPT II errors of omission or commissions scores and emotional problems, aggression, or learning problems. No significant correlations were found among the CPT II errors of omission score, commissions score, or RT and the WJ-III COG Auditory Attention subtest. A significant negative correlation was found between the CPT II variability score and the WJ-III COG Auditory Attention subtest. A significant positive correlation was found between the CPT II attentiveness score and the WJ-III COG Auditory Attention subtest. No significant correlations were found among any of the parent measures of attention problems Auditory Attention subtest. In a canonical correlation analysis there were high loadings on attention problems and hyperactivity/impulsivity on the parent-measure set and on commission errors and RT on the CPT II set. A modest loading on the multiple imputation set was also found on aggression problems and the parent-measure set. These findings support the overall conclusion that the CPT II does not generally relate to the parent-report measures. These findings indicate that there is little meaningful relationship between these two measures, which clinically are both used to assess attention problems.

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Ansari, Yousuf Hameed, and Sohaib Ahmed Siddiqui. "Quality Assessment for HEVC Encoded Videos: Study of Transmission and Encoding Errors." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13656.

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There is a demand for video quality measurements in modern video applications specifically in wireless and mobile communication. In real time video streaming it is experienced that the quality of video becomes low due to different factors such as encoder and transmission errors. HEVC/H.265 is considered as one of the promising codecs for compression of ultra-high definition videos. In this research, full reference based video quality assessment is performed. The raw format reference videos have been taken from Texas database to make test videos data set. The videos are encoded using HM9 reference software in HEVC format. Encoding errors has been set during the encoding process by adjusting the QP values. To introduce packet loss in the video, the real-time environment has been created. Videos are sent from one system to another system over UDP protocol in NETCAT software. Packet loss is induced with different packet loss ratios into the video using NETEM software. After the compilation of video data set, to assess the video quality two kind of analysis has been performed on them. Subjective analysis has been carried on different human subjects. Objective analysis has been achieved by applying five quality matrices PSNR, SSIM, UIQI, VFI and VSNR. The comparison is conducted on the objective measurement scores with the subjective and in the end results deduce from classical correlation methods.

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Gil, Gómez Gaspar. "Towards Efficient Vehicle Dynamics Evaluation using Correlations of Objective Metrics and Subjective Assessments." Licentiate thesis, KTH, Fordonsdynamik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169085.

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Servetkienė, Vaida. "Gyvenimo kokybės daugiadimensis vertinimas, identifikuojant kritines sritis." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2013~D_20131115_113802-40756.

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Disertacijoje nagrinėjama aktuali gyvenimo kokybės vertinimo problema. Mokslinėje literatūroje vis dar nėra vienodo gyvenimo kokybės suvokimo ir mokslinio apibrėžimo. Kiekvienas asmuo šiai sąvokai gali suteikti savo prasminį atspalvį, tačiau moksle gyvenimo kokybė turi būti konkrečiais rodikliais išreiškiama ir matuojama sąvoka, susijusi su visuomenės gerove konkrečioje šalyje. Šio darbo tyrimo objektas yra gyvenimo kokybės vertinimas. Disertacijos tikslas – išanalizavus mokslinius tarpdisciplininius požiūrius į gyvenimo kokybės vertinimą, parengti daugiadimensį gyvenimo kokybės vertinimo modelį ir nustatyti kritines jos sritis Lietuvoje. Darbe atlikta gyvenimo kokybės apibrėžties, koncepcijų ir praktikoje taikomų gyvenimo kokybės vertinimo metodų lyginamoji analizė, konceptualizuota gyvenimo kokybės sąvoka, ją traktuojant kaip ekonomikos mokslo tyrimo objektą, atspindintį valstybės vykdomos ekonominės politikos efektyvumą, nustatytos pagrindinės gyvenimo kokybės sritys, pateikta gyvenimo kokybės koncepcija ir pasiūlyti jos vertinimo metodologiniai principai, sudarytas daugiadimensis gyvenimo kokybės vertinimo modelis, jį taikant, įvertinta Lietuvos gyventojų gyvenimo kokybė ES šalių kontekste ir nustatytos kritinės jos sritys.
The dissertation examines the topical issue of assessment of the quality of life. Scientific literature still does not offer a uniform perception and scientific definition of the quality of life. Every person can provide this concept with his own interpretation, but in science the quality of life must be a concept expressed by means of specific indicators and measured in relation to the welfare of the population in a specific country. The object of research in this dissertation is the assessment of the quality of life. The aim of the dissertation is, upon analysing interdisciplinary scientific approaches to assessment of the quality of life, to develop a multidimensional model of assessment of the quality of life and to identify the critical areas of the quality of life in Lithuania. The author of the dissertation has carried out a comparative analysis of the definition and conceptions of the quality of life and the quality of life assessment methods employed in practice, conceptualised the concept of the quality of life treating it as an object of economic research which reflects the efficiency of the economic policy of the state, identified the key areas of the quality of life, provided a conception of the quality of life and proposed methodological principles for its assessment, developed a multidimensional quality of life assessment model and, by applying the model, evaluated the quality of life of the Lithuanian population in the context of the EU Member States and... [to full text]

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Bhattacharyya, Shounak, and Suraj Sivaramakrishnan. "Parameter Optimisation of EPAS Using CAE." Thesis, KTH, Fordonsdynamik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-261170.

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To keep up with technological as well as logistical challenges of the modern automobile market, major car manufacturing firms have resorted to virtual simulation tools. This enables the development as well as validation of vehicular models much before resources are invested into a new physical prototype.This project focuses on the development of a tool that would help in optimising the handling parameters of a vehicle. This is achieved by creating an optimization routine for tuning the various parameters of the Electronic Power Steering (EPAS). This process is usually done manually, by on-track testing, due to the difficulties in correlating Subjective Assessments (SA) with Objective Metrics (OM). Automating this process would help to reduce the overall research and development time, by providing a baseline tune for the EPAS parameters which could then be finely tweaked by manual track testing.The tool is built by interfacing various software in a multi-objective optimisation environment known as ModeFrontier. The modelling and simulations are performed in IPG CarMaker, with the post processing of the results taken care of by Sympathy for Data. Multiple optimization algorithms were tested to achieve the best optimisation routine. The EPAS parameters, namely the Basic Steering Torque, Active Return and Active Damping, act as the input to the optimization routine. The outputs of the model are the Objective Metrics, which provide a clear indication of the dynamic performance of a component. These metrics are optimized to _t the Steering DNA structure, which uniquely describes the attributes of a vehicle. The final optimised vehicle is manually tested at the track, to determine the real driving feel.
För att upprätthålla ett positivt momentum i såväl tekniska som logistiska utmaningar på dagens bilmarknad har stora biltillverkare börjat använda sig av virtuella simuleringsverktyg. Dessa verktyg möjliggör utveckling av diverse fordonsmodeller långt innan resurser investeras i en fysisk prototyp. Detta projekt fokuserar på utvecklingen av ett verktyg som potentiellt kan hjälpa att optimera dynamiska beteendeparametrar för ett fordon. Detta uppnås genom att skapa en optimeringsrutin för att ställa in de olika parametrarna för den elektroniska servostyrningen (EPAS). Denna process görs vanligtvis manuellt, genom test på provbana, på grund avsvårigheterna att korrelera subjektiva bedömningar (SA) med objektiva mätetal (OM). Att automatisera denna process kan bidra till att minska den övergripande forsknings- och utvecklingstiden genom att tillhandahålla en baslinje för EPAS-parametrarna som i efterhand kan ﬁnjusteras genom manuell justering på provbana. Verktyget är byggt genom att ansluta olika program i en optimeringsmiljö som kallas ModeFrontier. Modellering och simuleringar utförs i IPG CarMaker, med efterbehandling av resultaten i Sympathy for Data. Flera optimeringsalgoritmer testades för att uppnå bästa optimeringsrutinen. EPAS-parametrarna består av det grundläggande styrmomentet, aktiv retur och aktiv dämpning, och fungerar som invärden till optimeringsrutinen där utvärdera från modellen är objektiva mätetalen, vilket ger en tydlig indikation på den dynamiska prestandan hos en komponent. Dessa mätvärden optimeras för att passa Steering DNA-strukturen, som unikt beskriver egenskaperna hos ett fordon. Det slutliga optimerade fordonet testas manuellt på provbana för att bestämma den verkliga körkänslan.

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Englund, Sofia, and Sophie Karlerö. "En rekryterares bedömningsproblematik i vardagen : En fallstudie om objektiv- och subjektiv bedömning i rekryteringsprocessen." Thesis, Uppsala universitet, Institutionen för pedagogik, didaktik och utbildningsstudier, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-248555.

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I följande uppsats undersöker vi rekryterarens bedömningsproblematik i vardagen. Ämnet är relevant eftersom arbetsmarknaden ständigt utvecklas vilket innebär att rekryterarens objektiva bedömning har försvårats. Rekryteraren måste hitta en balansgång mellan den subjektiva och objektiva bedömningen. Studiens syfte är att undersöka rekryterarens perspektiv på och upplevelser om rekryteringsprocessen. För att få en djupare förståelse kring rekryterarnas bedömningsproblematik vid en rekrytering. Våra frågeställningar är följande: Vilken bedömningsproblematik möter rekryterare i vardagen? Hur kan rekryteraren hitta en balansgång mellan objektiv och subjektiv bedömning i rekryteringsprocessen? Utifrån vårt syfte och våra frågeställningar har vi genomfört en kvalitativ studie med semistrukturerade intervjuer. Vi har genomfört sex intervjuer med rekryterare på en offentlig verksamhet och två privata rekryteringsföretag. I denna studie utgår vi ifrån våra intervjupersoners åsikter, upplevelser och erfarenhet inom vårt ämnesområde. Empirin har transkriberats och analyserats med hjälp av en fenomenografisk analysmetod. Studiens resultat presenteras efter följande kategorier: Kravprofilen betydelse i en rekrytering, Att utföra en rättvis bedömning, Vikten av ett ärligt informationsutbyte, Bedömning av tillförlitligheten hos referenspersonerna och Hjälpmedel för objektiv bedömning. Sammanfattningsvis tyder resultatet på att rekryteraren har svårt att finna en balansgång mellan den subjektiva och objektiva bedömningen. Rekryterarna är medvetna om vilka problem som kan uppstå och kan med hjälp av deras erfarenhet finna lösningar på problemen. Problemen som uppstår vid en rekrytering skiljer sig inte emellan den offentliga verksamheten och rekryteringsföretagen. Avslutningsvis har vi diskuterat undersökningens resultat och analys utifrån våra teorier och modeller om rekrytering och bedömning.

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Špeta, Marek. "Programová implementace subjektivnich testů zvukové kvality." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219297.

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The focus of this diploma thesis is on methods for the subjective assessment of sound quality according to recommandations given by International Telecommunication Union ITU. The thesis is thematically divided into four parts. The first part is an interpretation of methods based on internationally accepted standards (method of small impairments, MUSHRA, general methods). The second part describes the functional blocks of application developed for this thesis in LabVIEW enviroment. Next part explains its practical application, especially its running possibilities. The last part describes a listening experiment, aim of which was to verify the application's features and to compare the results of the subjective method used in the experiment with the results of the objective method PEAQ.

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Sanches, Silvio Ricardo Rodrigues. "Avaliação objetiva de qualidade de segmentação." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3141/tde-26062014-111553/.

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A avaliação de qualidade de segmentação de vídeos tem se mostrado um problema pouco investigado no meio científico. Apesar disso, estudos recentes na área resultaram em algumas métricas que têm como finalidade avaliar objetivamente a qualidade da segmentação produzida pelos algoritmos. Tais métricas consideram as diferentes formas em que os erros ocorrem (fatores perceptuais) e seus parâmetros são ajustados de acordo com a aplicação em que se pretende utilizar os vídeos segmentados. Neste trabalho apresentam-se: i) uma avaliação da métrica que representa o estado-da-arte, demonstrando que seu desempenho varia de acordo com o algoritmo; ii) um método subjetivo para avaliação de qualidade de segmentação; e iii) uma nova métrica perceptual objetiva, derivada do método subjetivo aqui proposto, capaz de encontrar o melhor ajuste dos parâmetros de dois algoritmos de segmentação encontrados na literatura, quando os vídeos por eles segmentados são utilizados na composição de cenas em ambientes de Teleconferência Imersiva.
Assessment of video segmentation quality is a problem seldom investigated by the scientific community. Nevertheless, recent studies presented some objective metrics to evaluate algorithms. Such metrics consider different ways in which segmentation errors occur (perceptual factors) and its parameters are adjusted according to the application for which the segmented frames are intended. In this work: i) we demonstrate empirically that the performance of existing metrics changes according to the segmentation algorithm; ii) we developed a subjective method to evaluate segmentation quality; and iii) we contribute with a new objective metric derived on the basis of experiments from subjective method in order to adjust the parameters of two bilayer segmentation algorithms found in the literature when these algorithms are used for compose scenes in Immersive Teleconference environments.

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Greve, Line. "Objective assessment of thoracolumbar movement and posture in subjectively sound horses and those with hindlimb lameness." Thesis, Royal Veterinary College (University of London), 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.731284.

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Zerman, Emin. "Evaluation et analyse de la qualité vidéo à haute gamme dynamique." Electronic Thesis or Diss., Paris, ENST, 2018. http://www.theses.fr/2018ENST0003.

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Au cours de la dernière décennie, la technologie de l’image et de la vidéo à haute gamme dynamique (High dynamic range - HDR) a attiré beaucoup d’attention, en particulier dans la communauté multimédia. Les progrés technologiques récents ont facilité l’acquisition, la compression et la reproduction du contenu HDR, ce qui a mené à la commercialisation des écrans HDR et à la popularisation du contenu HDR. Dans ce contexte, la mesure de la qualité du contenu HDR joue un rôle fondamental dans l’amélioration de la chaîne de distribution du contenu ainsi que des opérations qui la composent, telles que la compression et l’affichage. Cependant, l’évaluation de la qualité visuelle HDR présente de nouveaux défis par rapport au contenu à gamme dynamique standard (Standard dynamic range -SDR). Le premier défi concerne les nouvelles conditions introduites par la reproduction du contenu HDR, par ex. l’augmentation de la luminosité et du contraste. Même si une reproduction exacte de la luminance d’une scène n’est pas nécessaire pour la plupart des cas pratiques, une estimation précise de la luminance émise est cependant nécessaire pour les mesures d’évaluation objectives de la qualité HDR. Afin de comprendre les effets du rendu d’affichage sur la perception de la qualité, un algorithme permettant de reproduire très précisement une image HDR a été développé et une expérience subjective a été menée pour analyser l’impact de différents rendus sur l’évaluation subjective et objective de la qualité HDR. En outre, afin de comprendre l’impact de la couleur avec la luminosité accrue des écrans HDR, les effets des différents espaces de couleurs sur les performances de compression vidéo HDR ont également été analysés dans une autre étude subjective. Un autre défi consiste à estimer objectivement la qualité du contenu HDR, en utilisant des ordinateurs et des algorithmes. Afin de relever ce défi, la thèse procède à l’évaluation des performances des métriques de qualité d’image HDR avec référence (Full reference-FR). Les images HDR ont une plus grande plage de luminosité et des valeurs de contraste plus élevées. Etant donné que la plupart des métriques de qualité d’image sont développées pour les images SDR, elles doivent être adaptées afin d’estimer la qualité des images HDR. Différentes méthodes d’adaptation ont été utilisées pour les mesures SDR, et elles ont été comparées avec les métriques de qualité d’image existantes développées exclusivement pour les images HDR. De plus, nous proposons une nouvelle méthode d’évaluation des métriques objectives basée sur une nouvelle approche de classification. Enfin, nous comparons les scores de qualité subjectifs acquis en utilisant différentes méthodologies de test subjectives. L’évaluation subjective de la qualité est considérée comme le moyen le plus efficace et le plus fiable d’obtenir des scores de qualité «vérité-terrain» pour les stimuli sélectionnés, et les scores moyens d’opinion (Mean opinion scores-MOS) obtenus sont les valeurs auxquelles les métriques objectives sont entraînées pour correspondre. En fait, de fortes divergences peuvent facilement être rencontrés lorsque différentes bases de données de qualité multimédia sont considérées. Afin de comprendre la relation entre les valeurs de qualité acquises à l’aide de différentes méthodologies, la relation entre les valeurs MOS et les résultats des comparaisons par paires rééchellonés (Pairwise comparisons - PC) a été comparée. A cette fin, une série d’expériences ont été menées entre les méthodologies double stimulus impairment scale (DSIS) et des comparaisons par paires. Nous proposons d’inclure des comparaisons inter-contenu dans les expériences PC afin d’améliorer les performances de rééchelonnement et de réduire la variance inter-contenu ainsi que les intervalles de confiance. Les scores de PC rééchellonés peuvent également être utilisés pour des scénarios subjectifs d’évaluation de la qualité multimédia autres que le HDR
In the last decade, high dynamic range (HDR) image and video technology gained a lot of attention, especially within the multimedia community. Recent technological advancements made the acquisition, compression, and reproduction of HDR content easier, and that led to the commercialization of HDR displays and popularization of HDR content. In this context, measuring the quality of HDR content plays a fundamental role in improving the content distribution chain as well as individual parts of it, such as compression and display. However, HDR visual quality assessment presents new challenges with respect to the standard dynamic range (SDR) case. The first challenge is the new conditions introduced by the reproduction of HDR content, e.g. the increase in brightness and contrast. Even though accurate reproduction is not necessary for most of the practical cases, accurate estimation of the emitted luminance is necessary for the objective HDR quality assessment metrics. In order to understand the effects of display rendering on the quality perception, an accurate HDR frame reproduction algorithm was developed, and a subjective experiment was conducted to analyze the impact of different display renderings on subjective and objective HDR quality evaluation. Additionally, in order to understand the impact of color with the increased brightness of the HDR displays, the effects of different color spaces on the HDR video compression performance were also analyzed in another subjective study. Another challenge is to estimate the quality of HDR content objectively, using computers and algorithms. In order to address this challenge, the thesis proceeds with the performance evaluation of full-reference (FR) HDR image quality metrics. HDR images have a larger brightness range and higher contrast values. Since most of the image quality metrics are developed for SDR images, they need to be adapted in order to estimate the quality of HDR images. Different adaptation methods were used for SDR metrics, and they were compared with the existing image quality metrics developed exclusively for HDR images. Moreover, we propose a new method for the evaluation of metric discriminability based ona novel classification approach. Motivated by the need to fuse several different quality databases, in the third part of the thesis, we compare subjective quality scores acquired by using different subjective test methodologies. Subjective quality assessment is regarded as the most effective and reliable way of obtaining “ground-truth” quality scores for the selected stimuli, and the obtained mean opinion scores (MOS) are the values to which generally objective metrics are trained to match. In fact, strong discrepancies can easily be notified across databases when different multimedia quality databases are considered. In order to understand the relationship between the quality values acquired using different methodologies, the relationship between MOS values and pairwise comparisons (PC) scaling results were compared. For this purpose, a series of experiments were conducted using double stimulus impairment scale (DSIS) and pairwise comparisons subjective methodologies. We propose to include cross-content comparisons in the PC experiments in order to improve scaling performance and reduce cross-content variance as well as confidence intervals. The scaled PC scores can also be used for subjective multimedia quality assessment scenarios other than HDR

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Ševčík, Martin. "Modelování vlastností modelu HVS v Matlabu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217656.

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In theoretical part Diploma thesis deals with the model of human vision HVS (Human Visual System), which can be used for image quality assessment in TV technique area. It has been described calculations of selected JND (Just Noticeable Difference) metrics, used in evaluation of HVS. In practical part of the thesis it has been suggested and realized simulation model in Matlab, which may be used for evaluation of three JND metrics from color and grayscale images and evaluation in spatial a frequency domain. Results of JND models have been compared to another objective image quality evaluation metrics (MSE, NMSE, SNR and PSNR). For interpretation of dependencies it has been used images with different defined content.

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Hobson, Biano. "Objective and subjective assessment of chronic disease management in General Practice. To determine the standard of care provided in the management of asthma, gout and hypothyroidism by means of a medical audit." Thesis, Stellenbosch : University of Stellenbosch, 2015. http://hdl.handle.net/10019.1/97247.

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Asthma, gout and hypothyroidism are common chronic medical disorders encountered in general practice. Optimal disease management according to standard guidelines are fundamental to disease control. This study aimed to objectively and subjectively assess the quality of care provided in a private general practice to patients with asthma, gout and hypothyroidism by means of a practice audit and questionnaire based survey. These tools proved to be an effective measure for the quality of care provided and identified areas needing improvement. Patient’s understanding of the disease process plays an important role in both patient satisfaction ratings and success of disease control. The medical audit identified and highlighted specific areas of care that can be improved. Evidence from the practice audit showed that control for asthma based on the PEFR readings, gout based on the serum uric acid reading and hypothyroidism based on a blood TSH reading, was found at 56.7%, 43.3%, and 66.7 % respectively. In addition acute attacks of asthma and gout occurred in 22.7% and 32.8% respectively. This does not represent good control. Definition of disease control for each condition is placed in the text. The survey revealed overall patient understanding for the disease processes of asthma, gout and hypothyroidism to be 69.6%, 73.3% and 66.8% respectively. The patient survey satisfaction rating for asthma, gout and hypothyroidism was 93.1%, 93.9% and 89.2% respectively. Patient suggestions for improvement included three dominant themes: better assessment of disease control, education about their chronic disease and implementation of a clearer referral process. The study concludes that disease control can be achieved if patients are educated about their chronic disease and regularly followed up to assess disease control based on standard management guidelines. Patients' disease education was a major contributing factor for satisfaction rating bias. The study confirms that in spite of high satisfaction ratings, patients are not optimally managed with substandard disease control. It would be expected that as disease education improves, the quality of care will improve, but satisfaction ratings will decrease.

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Abdou, Dalia Ahmed Selim Ali. "Three dimensional (3D) forensic facial reconstruction in an Egyptian population using computed tomography scanned skulls and average facial templates : a study examining subjective and objective assessment methods of 3D forensic facial reconstructions." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/41763.

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Forensic facial reconstruction can assist identification by reconstructing a face of the unknown person with the aim of its recognition by his/her family or friends. In the facial reconstruction approach adopted in this study, a 3D average face template was digitally warped onto a 3D scanned skull image. This study was carried out entirely on an Egyptian population, and was the first of its kind. Aims: This study aimed to demonstrate that 3D facial reconstructions using the novel methodology described could show significant resemblance to the faces corresponding to the persons in question when they were alive. Moreover, using techniques previously validated for facial reconstruction, the aim was to compare them to the method developed, and to assess approaches used to determine the accuracy of 3D facial reconstructions. Methods: Initially, a pilot study was conducted using a database of laser scanned skulls and faces. The faces were reconstructed using an average facial template generated by merging a number of faces of similar population, sex, and age. The applicability, as well as the main components of the facial reconstruction method, the single and average facial templates, and the facial soft tissue thickness measurements, were investigated. Furthermore, in the main study, the faces of computed tomography (CT) scanned heads of an Egyptian population were reconstructed using average facial templates. The accuracy of the reconstructed faces was assessed subjectively by face pool, and face resemblance tests, and objectively by measuring the surface distances between the real and reconstructed faces. In addition, a number of novel subjective and objective assessment methods were developed. These included assessment of individual facial regions using subjective resemblance scores, and objective surface distance comparisons. A new objective method, craniofacial anthropometry, was developed by taking and comparing direct measurements from the skull, and comparing the measurements from the real and reconstructed faces. The studied cases were ranked according to all subjective, and objective, tests, and statistically correlated. Results and Conclusions: The average facial templates showed a higher identification rate than the single face templates. The approach of facial reconstruction used in this thesis showed a comparable accuracy to many other facial reconstruction methods, yet was superior in terms of its applicability, transferability, and ease of use. In the face pool tests, the younger assessors were able to correctly identify the reconstructed faces better than older assessors. Furthermore, the identification rate by the forensic anthropology experts was higher than the non-experts. The former group showed the highest agreement between the observers in giving the resemblance scores. Although there was a significant rank correlation between the subjective and objective assessment tests, the subjective tests are influenced by the assessors' subjective characteristics (e.g., age, professional experience), thus making objective assessment more reliable. However, in situations where subjective tests are used, it is better to use the face resemblance tests and consult forensic anthropologists. Also, Craniofacial Anthropometry, particularly the craniofacial angles, can successfully indicate the accuracy of the facial reconstructions. Importantly, this study shows that certain facial regions, particularly the cheek and the jaw, are more reliable than other areas in the subjective and objective assessment of the facial reconstruction.

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Smith, Kathryn Elizabeth. "THE URGE TO PURGE: AN ECOLOGICAL MOMENTARY ASSESSMENT OF PURGING DISORDER AND BULIMIA NERVOSA." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1416829240.

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Nouri, Nedia. "Évaluation de la qualité et transmission en temps-réel de vidéos médicales compressées : application à la télé-chirurgie robotisée." Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL049N/document.

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L'évolution des techniques chirurgicales, par l'utilisation de robots, permet des interventions mini-invasives avec une très grande précision et ouvre des perspectives d'interventions chirurgicales à distance, comme l'a démontré la célèbre expérimentation « Opération Lindbergh » en 2001. La contrepartie de cette évolution réside dans des volumes de données considérables qui nécessitent des ressources importantes pour leur transmission. La compression avec pertes de ces données devient donc inévitable. Celle-ci constitue un défi majeur dans le contexte médical, celui de l'impact des pertes sur la qualité des données et leur exploitation. Mes travaux de thèse concernent l'étude de techniques permettant l'évaluation de la qualité des vidéos dans un contexte de robotique chirurgicale. Deux approches méthodologiques sont possibles : l'une à caractère subjectif et l'autre à caractère objectif. Nous montrons qu'il existe un seuil de tolérance à la compression avec pertes de type MPEG2 et H.264 pour les vidéos chirurgicales. Les résultats obtenus suite aux essais subjectifs de la qualité ont permis également de mettre en exergue une corrélation entre les mesures subjectives effectuées et une mesure objective utilisant l'information structurelle de l'image. Ceci permet de prédire la qualité telle qu'elle est perçue par les observateurs humains. Enfin, la détermination d'un seuil de tolérance à la compression avec pertes a permis la mise en place d'une plateforme de transmission en temps réel sur un réseau IP de vidéos chirurgicales compressées avec le standard H.264 entre le CHU de Nancy et l'école de chirurgie
The digital revolution in medical environment speeds up development of remote Robotic-Assisted Surgery and consequently the transmission of medical numerical data such as pictures or videos becomes possible. However, medical video transmission requires significant bandwidth and high compression ratios, only accessible with lossy compression. Therefore research effort has been focussed on video compression algorithms such as MPEG2 and H.264. In this work, we are interested in the question of compression thresholds and associated bitrates are coherent with the acceptance level of the quality in the field of medical video. To evaluate compressed medical video quality, we performed a subjective assessment test with a panel of human observers using a DSCQS (Double-Stimuli Continuous Quality Scale) protocol derived from the ITU-R BT-500-11 recommendations. Promising results estimate that 3 Mbits/s could be sufficient (compression ratio aroundthreshold compression level around 90:1 compared to the original 270 Mbits/s) as far as perceived quality is concerned. Otherwise, determining a tolerance to lossy compression has allowed implementation of a platform for real-time transmission over an IP network for surgical videos compressed with the H.264 standard from the University Hospital of Nancy and the school of surgery

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Bršel, Boris. "Porovnání objektivních a subjektivních metrik kvality videa pro Ultra HDTV videosekvence." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-241052.

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Master's thesis deals with the assessment of quality of Ultra HDTV video sequences applying objective metrics. Thesis theoretically describes coding of selected codecs H.265/HEVC and VP9, objective video quality metrics and also subjective methods for assessment of the video sequences quality. Next chapter deals with the implementation of the H.265/HEVC and the VP9 codecs at selected video sequences in the raw format from which arises the test sequences database. Quality of these videos is measured afterwards by objective metrics and selected subjective method. These results are compared for the purpose of finding the most consistent correlations among objective metrics and subjective assessment.

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Bain, Jonathan. "Subjective-Objective-Subjective: The Science Of Propaganda." Master's thesis, Faculty of Law, 2020. http://hdl.handle.net/11427/32197.

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This thesis discusses the following: 1. That, while advertising practitioners employ various levels of scientific endeavour (particularly strategic insight development, but also research, demographic data collection, and other objective tools of the trade), its final output is ultimately nonscientific, i.e. subjective creative ideation. (In this way, advertising is not dissimilar to the classic ‘art' of propaganda.) 2. That, for reasons of business necessity, creative ego and a latent form of ‘inferiority complex' the advertising industry describes its work in presentations to more scientifically-orientated clients as a more scientific proposition. 3. That, in contrast, as evidenced by the physical production process of the advertising idea (post the client presentation) – as well as in industry texts, award ceremonies, and selected case studies – advertising practitioners effectively acknowledge the subjective nature of their work. 4. That further evidence of this scientific ‘terministic screen' (Burke 1950, pp. 26-27) is also revealed in the failure of some television commercials to profitably ‘connect' as intended with an audience – thus undermining claims to the objective approach that preceded these commercials. 5. That, possibly, as is implied in at least one ethnographic case study, not even clients are necessarily convinced by advertising science: the ‘screen' may be a two-way mirror. 6. That there is, more broadly, a constant dialectic between right-brained creativity and the left-brained business project. 7. That this tension is a microcosm of the capitalist enterprise, and, in an increasing number of present examples, is perversely reflected in the advertising industry's output as anti-capitalist brand messaging. 8. That it is possible to think of advertising as a sub-set of a more consumer-orientated ‘design'. 6 9. That, admittedly within limited confines of my research, there is a tantalising indication that, generally, advertising artefacts were historically more logos-led, are currently more pathos-led, and may in future benefit from a more ethos-led orientation.

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Begazo, Dante Coaquira. "Método de avaliação de qualidade de vídeo por otimização condicionada." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-09032018-152946/.

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Esta Tese propõe duas métricas objetivas para avaliar a percepção de qualidade de vídeos sujeitos a degradações de transmissão em uma rede de pacotes. A primeira métrica usa apenas o vídeo degradado, enquanto que a segunda usa os vídeos de referência e degradado. Esta última é uma métrica de referência completa (FR - Full Reference) chamada de QCM (Quadratic Combinational Metric) e a primeira é uma métrica sem referência (NR - No Reference) chamada de VQOM (Viewing Quality Objective Metric). Em particular, o procedimento de projeto é aplicado à degradação de variação de atraso de pacotes (PDV - Packet Delay Variation). A métrica NR é descrita por uma spline cúbica composta por dois polinômios cúbicos que se encontram suavemente num ponto chamado de nó. Para o projeto de ambas métricas, colhem-se opiniões de observadores a respeito das sequências de vídeo degradadas que compõem o conjunto. A função objetiva inclui o erro quadrático total entre as opiniões e suas estimativas paramétricas, ainda consideradas como expressões algébricas. Acrescentam-se à função objetiva três condições de igualdades de derivadas tomadas no nó, cuja posição é especificada dentro de uma grade fina de pontos entre o valor mínimo e o valor máximo do fator de degradação. Essas condições são afetadas por multiplicadores de Lagrange e adicionadas à função objetiva, obtendo-se o lagrangiano, que é minimizado pela determinação dos coeficientes subótimos dos polinômios em função de cada valor do nó na grade. Finalmente escolhe-se o valor do nó que produz o erro quadrático mínimo, determinando assim os valores finais para dos coeficientes do polinômio. Por outro lado, a métrica FR é uma combinação não-linear de duas métricas populares, a PSNR (Peak Signal-to-Noise Ratio) e a SSIM (Structural Similarity Index). Um polinômio completo de segundo grau de duas variáveis é usado para realizar a combinação, porque é sensível a ambas métricas constituintes, evitando o sobreajuste em decorrência do baixo grau. Na fase de treinamento, o conjunto de valores dos coeficientes do polinômio é determinado através da minimização do erro quadrático médio para as opiniões sobre a base de dados de treino. Ambas métricas, a VQOM e a QCM, são treinadas e validadas usando uma base de dados, e testadas com outra independente. Os resultados de teste são comparados com métricas NR e FR recentes através de coeficientes de correlação, obtendo-se resultados favoráveis para as métricas propostas.
This dissertation proposes two objective metrics for estimating human perception of quality for video subject to transmission degradation over packet networks. The first metric just uses traffic data while the second one uses both the degraded and the reference video sequences. That is, the latter is a full reference (FR) metric called Quadratic Combinational Metric (QCM) and the former one is a no reference (NR) metric called Viewing Quality Objective Metric (VQOM). In particular, the design procedure is applied to packet delay variation (PDV) impairments, whose compensation or control is very important to maintain quality. The NR metric is described by a cubic spline composed of two cubic polynomials that meet smoothly at a point called a knot. As the first step in the design of either metric, the spectators score a training set of degraded video sequences. The objective function for designing the NR metric includes the total square error between the scores and their parametric estimates, still regarded as algebraic expressions. In addition, the objective function is augmented by the addition of three equality constraints for the derivatives at the knot, whose position is specified within a fine grid of points between the minimum value and the maximum value of the degradation factor. These constraints are affected by Lagrange multipliers and added to the objective function to obtain the Lagrangian, which is minimized by the suboptimal polynomial coefficients determined as a function of each knot in the grid. Finally, the knot value is selected that yields the minimum square error. By means of the selected knot value, the final values of the polynomial coefficients are determined. On the other hand, the FR metric is a nonlinear combination of two popular metrics, namely, the Peak Signal-to-Noise Ratio (PSNR) and the Structural Similarity Index (SSIM). A complete second-degree two-variable polynomial is used for the combination since it is sensitive to both constituent metrics while avoiding overfitting. In the training phase, the set of values for the coefficients of this polynomial is determined by minimizing the mean square error to the opinions over the training database. Both metrics, the VQOM and the QCM, are trained and validated using one database and tested with a different one. The test results are compared with recent NR and FR metrics by means of correlation coefficients, obtaining favorable results for the proposed metrics.

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Chen, David. "Subjective and objective vehicle handling behaviour." Thesis, University of Leeds, 1997. http://etheses.whiterose.ac.uk/627/.

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This thesis presents results from a research project seeking to correlate subjective and objective measures of automobile handling. An underlying goal of the work was to demonstrate how a relatively simple lumped parameter model, suitable for effective use at the early stages of vehicle design, could be used to predict both the objective responses and subjective feel of the car. The work associated with the project was centred around sixteen configurations of a prototype saloon car. Objective evaluation included ISO defined steady state, step input, and frequency response testing. Subjective assessments were conducted by eight trained test drivers who supplied feedback in the form of numerical ratings on a questionnaire covering various aspects of handling. Examination of the two sets of data highlighted aspects of handling for which driver ratings correlated with objective data. It was also possible to quantify the average effect each objective response parameter had on driver ratings and thus to identify responses which most strongly influence subjective ratings. In addition a lumped parameter model allowing for lateral, yaw and roll degrees of freedom was validated against the experimental data. This validation demonstrated that the model was capable of accurate steady state and transient predictions both in the linear and non-linear range. The work concludes with a brief discussion about how the validated model, combined with the knowledge gained from the correlation work, could be used by engineers to streamline the design and development process.

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Nabi, Ghulam Rasul. "Predictors of objective and subjective career success." Thesis, University of Central Lancashire, 1999. http://clok.uclan.ac.uk/20076/.

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The main aim of this research was to examine predictors of both objective (salary). and subjective (perceived) career success. Three sets of predictors were examined: (1) individual attributes, (2) organisational opportunity structures and (3) career strategies. It was expected that a different pattern of variables would predict objective and subjective career success. In addition, the mediating role of career strategies was examined. It was expected that individual attributes and opportunity structures would be positively related to the use of career strategies, and that these strategies would be positively related to career success. Cross-sectional survey methodology was employed to collect data from a sample of 723 full-time employees in administrative/ technical, academic and managerial posts at several British universities. According to expectations, a different pattern of variables was related to objective and subjective career success. The strongest predictors of objective career success were education, organisational size and extended work involvement. In contrast, the strongest predictors of subjective career success were internal labour market perceptions of structured career progression and employment security. Separate analyses by gender and occupational group revealed a similar difference in the profile of predictors of objective and subjective career success. Overall, the results suggested that the variables that related to objective career success were often not the same as those related to subjective career success. This was taken as support for the main theme of this research that objective and subjective career success, although related, are substantially distinct concepts. Contrary to expectation, however, the results provided limited support for the mediating role of career strategies in the relationship between individual attributes, organisational opportunity structures and career success (objective and subjective). Only individual attributes (education and work centrality) were positively related to the use of career strategies (extended work involvement, selfpromotion and networking), and these strategies in turn were positively related to objective or subjective career success. However, the mediating role of career strategies was weak, albeit statistically significant. A number of limitations, mainly regarding the cross-sectional nature of the study, are discussed. Educational and organisational implications of the findings are suggested. Finally, a two-dimensional model of career success is proposed, incorporating the findings of the present research with reference to the predictors of objective and subjective career success, together with suggestions for further research.

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TANG, Yihao, and Hui ZHU. "Test method development by use of SOM-GRNN." Thesis, KTH, Fordonsdynamik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-243286.

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The relationship between Objective Metrics (OM) and Subjective Assessments (SA) has been analyzed by people using different methods. This paper continues Gaspar Gil Gómez’s research over test method development by use of SOM-GRNN, aiming to find correlations between OM and SA. In this paper, CAE simulation is performed to analyze the relationship between OM and vehicle parameters. First impression test is refined and one more dataset has been added in order to populate SOM-GRNN map. This paper also conducts analysis over SOM and GRNN algorithms, and explores several possible applications using SOM-GRNN map. Finally the whole SOM-GRNN system is integrated and a User Interface is built in GUI for future research and application. The system can still be improved by populating database, refining SA evaluation method and optimizing SOM-GRNN training algorithms.
Relationen mellan målmetri (OM) och subjektiv bedömning (SA) har analyserats av personer som använder olika metoder. I detta dokument fortsätter Gaspar Gil Gómezs forskning kring testmetodutveckling med hjälp av SOM-GRNN, som syftar till att finna korrelationer mellan OM och SA. I detta papper utförs CAE-simulering för att analysera förhållandet mellan OM och fordonsparametrar. Första intryckstestet är raffinerat och ytterligare en dataset har lagts till för att fylla i SOM-GRNN-kartan. I detta dokument analyseras även SOM- och GRNN-algoritmer, och undersöker flera möjliga tillämpningar med hjälp av SOM-GRNN kartan. Slutligen är hela SOM-GRNN-systemet integrerat och ett användargränssnitt är byggt i GUI för framtida forskning och tillämpning. Systemet kan fortfarande förbättras genom att fylla i databasen, förädla SA utvärderingsmetod och optimera SOM-GRNN träningsalgoritmer.

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Meit, Heather Anderson. "Objective and subjective personality characteristics of medical students." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1919.

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Thesis (Ph. D.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains vi, 68 p. : ill. Includes abstract. Includes bibliographical references (p. 55-62).

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Hall, Courtney D. "Assessment of Subjective Complaints." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5379.

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Malekmohamadi, Hossein. "Objective models for subjective quality estimate of stereoscopic video." Thesis, University of Surrey, 2013. http://eprints.lincoln.ac.uk/12756/.

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Vonstad, Elise Klæbo. "Exergaming for Elderly: Subjective Experiences and Objective Movement Characteristics." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for nevromedisin, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25610.

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Background: It is important for elderly to stay healthy and independent for as long as possible, and falls are a major cause for loss of independence. Physical activity aimed at improving balance that includes large movements and cognitive tasks has been shown to decrease fall risk. Using exergames as a training tool has increased in recent years, but the actual movements elicited by such exergames have yet to be investigated objectively. Aim: To investigate usability and enjoyment and provide objective quantification of movement size elicited by two exergames. Methods: Twenty healthy elderly (mean age 74.4, range 65-90) played two exergames, The Mole (SilverFit) and LightRace (YourShape: Fitness Evolved) at easy and medium level, with five trials of one minute at each level. Data on perceived exertion (BORG), enjoyment and system usability (SUS) was collected.. Movements were captured using OQUS Motion Capture System, with passive reflexive markers attached to the base of the 1st toe, heel and lumbar area of the back. Movement size was expressed as Interquartile range (IQR) of feet and trunk in all three directions, and as horizontal area covered by the lumbar and toe markers. Correlational analyses were performed to investigate relationships between game scores, BORG-scores, SUS-scores, IQR and area coverage. Repeated measures ANOVAs were used to analyze effects of game, level, and trial. Results: Both games scored high on usability, and the elderly perceived the games as enjoyable, relevant as physical activity, and not very exhausting. Game scores increased across trials and decreased from easy to medium levels. Nevertheless, participants preferred the medium over the easy levels because of the increased cognitive challenge. IQR and area in the feet exceeded those in the trunk, especially in the medio-lateral direction. There were no significant correlations between game score and movement variables. Discussion: The positive attitude from the participants is promising for future implementation of exergames into fall preventive exercises. However, the lack of correlations between game scores and movement variables indicate that although these exergames do not reward players for "cheating" movements; they have room for improvement concerning rewarding desired movements. Keywords: older adults, exergames, movement characteristics, stepping.

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Balderas, Gustavo. "Objective Versus Subjective Discipline Referrals in a School District." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/18722.

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Seven percent of all students are excluded from school every year across the United States for violating school policies and procedures. Exclusion from school causes a number of problems for students such as higher dropout rates, grade retention, more of a likelihood of not graduating from high school, and a widening of the achievement gap. However, the literature review reveals a lack of exclusion research specific to Hispanic students. Therefore, this research study investigated the level of disciplinary referrals leading to student suspensions during the 2013-2014 school year in a southern California school district of 9223 students with a student demographic composed of 39% free-and-reduced meals, 24% English language learners, and 36% Hispanic. The research study analyzed not just referrals but differences between subjective versus objective referrals for Hispanic and White students. Risk ratio results indicated that Hispanic students were more likely to receive referrals that resulted in suspensions from school at two-and-one-half times the rate compared to their White peers for both subjective (RR = 2.572) and objective (RR = 2.600) referrals. While there was no difference, p = .308, between referrals labeled as subjective versus objective, Hispanic students were significantly more likely to receive objective (p = .017) and subjective (p = .041) disciplinary referrals that resulted in suspensions compared to their White peers. The most significant factors that predicted overall student disciplinary referrals were English language learner status and free and reduced meals. In particular, English language status accounted for 60% of all referrals leading to a student suspension. Oppositely, factors that had the least predicted referral infractions were talented and gifted status, parent education level, and special education status. Results from this study provided school district staff with information that helped to revise district policy and procedures regarding the use of the suspension as an enforcement tool in student discipline, with particular focus on subjective versus objective referrals that could lead to student suspension. Implications of this research are discussed in relation to practice, procedures, and policies.

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Bordel, Stéphanie. "Les dimensions objective et subjective du jugement de responsabilité." Rennes 2, 2002. http://www.theses.fr/2002REN20038.

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La @responsabilité apparaît comme une notion difficile à saisir. En effet, cette notion, qui appartient à la fois au langage ordinaire et au langage juridique, présente un caractère polysémique. Cependant, au-delà des divergences et des contradictions, il est possible, en s'appuyant notamment sur l'analyse sociologique de Fauconnet (1920) et les travaux de Piaget (1932) de distinguer deux types de responsabilité : la responsabilité objective et la responsabilité subjective. Ainsi, définir la responsabilité d'une personne reviendrait, d'une part, à chercher son rôle causal dans la production de l'évènement observé, c'est-à-dire à attribuer la causalité, il s'agit de la respondabilité objective, et d'autre part à prendre en compte des aspects plus téléologiques comme l'intentionnalité ou les raisons, il s'agit de la responsabilité subjective. . Cette proposition théorique a fait l'objet d'une validation empirique. Quatre séries d'études ont permis de mettre en évidence que la responsabilité peut effectivement être définie comme renvoyant à ces deux éléments, mais qu'ils sont indissociables l'un de l'autre. En effet, la responsabilité évoque toujours la responsabilité objective et la responsabilité subjective, et ce, quelle que soit l'information donnée aux sujets. Par ailleurs, il apparaît que les sujets, issus de sociétés ayant des droits différents, n'accordent pas une place identique à la responsabilité objective et à la responsabilité subjective
The @responsibility appears like a difficult notion to understand. In fact, this word is part, at the same time, of ordinary language and juridcal language, it has a polysemic character. Far from those differences and contradictions, however, basing on the sociological analysis of Fauconnet (1920) and Piaget's work (1932), it is possible to distinguish two types of responsibility : objective responsibility and subjective responsibility. In this way, to define responsibility of a person would be, on one hand to search his causal role in the facts that are observed. This means doing causal attribution, it is the objective responsibility. On the other hand, it would be the research of teleological aspects like intentionnality or reasons, it is the subjective responsibility. This theoretical proposition forms the subject of an empirical validation. Four series of studies have shown that responsibility can in the facts be defined by those two components but that there are indissociable. Responsibility always recall to both objective responsibility and subjective responsibility whatever informations are given to the subjects. In other respects, it appears that the subjects, all coming from different societies with different laws, don't give the same place to objective responsibility and subjective responsibility

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Witherwax, Renee Ann. "The subjective made manifest through interpretation of the objective." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1314633976.

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STEPINSKI, JOY DIANA. "OBJECTIVE AND SUBJECTIVE MEASUREMENTS OF NORMAL AND OVER HYDRATION." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin990804483.

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Ash, Howard Alan Simon. "Correlation of subjective and objective handling of vehicle behaviour." Thesis, University of Leeds, 2002. http://etheses.whiterose.ac.uk/609/.

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This thesis presents the results of a research project which sought to find links between driver subjective ratings and objective measures of vehicle handling. The experimental data used in this project has been made available from a previous research project. The experimental data was collected using a prototype vehicle which was used in 16 different configurations. Objective data was collected based around the ISO defined steady state, step input, and frequency response tests. Subjective assessments were collected from eight trained test drivers using a numerical rating scale to a questionnaire covering various aspects of vehicle handling. Analysis of the subjective assessments has been done to identify any shortcomings that may affect any subsequent analysis. From the literature review, an approach that claims to relate four simple objective metrics to subjective measures of vehicle handling has been developed in two new ways. Firstly, the proposal was tested [1] with the large amount of subjective data available to see if good levels of correlation could be found between the proposed metrics and driver subjective ratings to specific handling questions. Secondly, the method was extended to include further simple metrics to try and improve links between the subjective and objective data [2]. Non-linear relationships in the correlation of subjective vs. objective data have been investigated for the first time [3] using non-linear genetic algorithms, which, in addition have not previously been used to correlate driver subjective ratings with objective measures that describe vehicle handling. From the results, it has been possible to specify ranges of preferred values of objective metrics in order to produce a subjectively satisfying vehicle. Finally, the work discusses how the results obtained can be used by engineers to aid the vehicle design and development process.

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Perry, Darren. "Relationship between objective impairment, subjective psychological factors and PCS." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397568.

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Williams, Nicola Kim. "Objective predictors of subjective aesthetic ratings of web pages." Thesis, Keele University, 2015. http://eprints.keele.ac.uk/2324/.

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This research is concerned with the effect of visual stimulus on decision-‐making and opinions, what visual aspects of a page affect very early impressions of web sites, and how this relates to computational methods of prediction and evaluation of web pages. The aim of this study was to discover whether there are identifiable visual attributes of web pages that can be used to predict subjective opinions. This was explored through three separate studies. These consisted of two correlational studies and a categorisation task. Participants were gained through convenience and snowball sampling, and the materials reviewed were two distinct sets of web pages. Cards sorts, laddering and an online data collection tool were used to gather the information. Both qualitative and quantitative analysis was used to explore the information. The visual attributes found to correlate with subjective opinions were inconsistent across the two correlational studies. Study One had a number of limitations that may have contributed to this inconsistency. Concrete findings were that levels of encouragement and discouragement influenced by web pages are on two distinct scales, as, although there is a negative correlation between them, a large number of pages were rated poorly on both scales. The similarity between the card sort and questionnaire results had consistent findings for predictors of low-‐rated web pages. The findings from the cards sorts also show that users are able to make preference judgements of web pages without being able to understand the content. An application of the findings regarding prediction of low-‐rated pages would be to create web design optimisation system, enabling web pages to be reviewed computationally. Although this should never replace user testing, it may provide an economical alternative during the early stages of design.

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Bednarz, Robin. "Analýza kvality obrazu v digitálních televizních systémech." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217810.

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Diploma thesis deals with the analysis of quality in digital television systems and contains theoretical description of subjective and objective assessment of quality picture methods. The thesis contains short-term and long-term analysis of quality picture of terrestrial television DVB-T. Measurements and experimentations were carried out with the help of Rohde&Schwarz DVQ analyzer of picture quality and software MPEG-2 Quality Monitor and MPEG-2 Elementary stream analyzer.

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Murray, Caroline Siân. "Measuring disease in dermatology : studies of objective and subjective methods." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/23594.

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Itch lies second only to disturbance of body image as a reported symptom in dermatology. This study started by concentrating on improving the measurement of itch. Itch has a paired physical response, scratch. The pairing can be exploited: preliminary work by this unit had validated the use of wrist-worn movement-measuring machines called ‘accelerometers’ to measure itch-related movement (scratch and rub). The first part of this research developed use of these machines. Simple accelerometers (‘Actiwatch Plus’) were used to observe the pattern of variation of itch over clusters of nights and in different conditions. The accelerometer scores were able to identify controls’ scores from those with itchy disease. Considerable variation (56%) was discovered in objective score between subject and considerable variation was noted (46%) even within subject. More complex accelerometers, (‘DigiTrac’) which could potentially specifically identify itch-related movement on the basis of frequency of action derived from Fast Fourier Transform (FFT), were validated against the ‘gold standard’ measurement of itch-related movement, directly observed movement (via infra red video recording). It was necessary to characterise the ‘frequency of action’ of itch on video and, as an aside, the characteristics of human itch-related movement were compared to other mammals’ itch-related movement ‘frequency of action’. The ‘frequency of action’ and video data was used to enrich the DigiTrac readouts to improve specificity of itch-related movement detection. During the accelerometer studies, an unexpected finding came to light: objective score of itch was not related to subjective score. To try to explain the lack of relationship, a 42 day longitudinal study of atopic dermatitis patients’ subjective and objective scores was undertaken. The results demonstrated autocorrelation for subjective scores, but not for the objective scores but still did not fully explain the lack of relationship. In an effort to explain the disconnect between subjective and objective scores a second tranche of experiments and the second part of this research interrogated whether the methods with which we measure disease as a whole in dermatology are robust. One study investigated whether the way patients are asked about subjective symptoms in general was resistant to the effects of focusing and framing bias. The results were reassuring as they suggested that the commonly used and recommended symptom scoring systems were robust in the face of bias. In order to assess whether perspective or perception of disease explained the disconnect, a study was designed in collaboration with the Edinburgh College of Art. A series of computer-generated images of different psoriasis severities were created and used to assess how doctors and patients assessed disease-extent. This study showed that, whilst each group had a naturally divergent opinion of extent of disease, by scoring disease using the models it was possible to unify the perspective and perception of extent. Finally, an exploratory study to reduce recall bias to a minimum, in case this had caused the disconnect between objective and subjective, was undertaken. This employed a novel questionnaire, the Day Reconstruction Method.

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Dissertations / Theses on the topic 'Objective- and subjective assessment'

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