The diploma thesis deals with the optimization of powder-coating process resulting in a reduction of labor intensity during finishing components in gas insulated switchgear (GIS). The thesis is divided into five main chapters that describe characteristic and function of gas insulated switchgear (GIS), the theory of powder-coating, including mechanical and chemical pretreatment of surfaces, the studies of contemporary quality of coating process in the company ABB s.r.o. with classification of components of GIS according to their function. This chapter also contains detailed analysis of section of coating process during the processing of selected parts (housing and conductor). The thesis also contains detailed studies of masking of surfaces at coating parts, specifies the most common defects and determines the main cause presented in a well-arranged chart, design, description and realization of optimization solutions with selection and evaluation of final version. An economic comparison of contemporary condition of powder-coating process with designed optimization solution is stated at the end of the thesis.

Denna studie undersöker hur flickor som går högskoleförberedande program på gymnasiet ser på det stöd de får i skolan och hur de kan visa och få sina stödbehov tillgodosedda i övergången mellan grundskolan och gymnasiet. Syftet är att bidra med kunskap om övergången mellan grundskola och gymnasium för flickor som befinner sig i behov av stöd kring sin skolgång och hur denna kunskap kan bidra till att flickor får sina stödbehov tillgodosedda. Studien är en kvalitativ intervjustudie med en hermeneutisk metod och engenusteoretisk utgångspunkt. Genom ett elevperspektiv studeras vad forskning och flickorna som intervjuats kan bidra med för vidare forskning och för att ur ett specialpedagogiskt perspektiv bidra till skolutveckling och en förändrad skolpraktik. Detta för att flickorförhoppningsvis får sina stödbehov tillgodosedda under sin skolgång och framför allt i övergången mellan grundskolan och gymnasiet. Forskningen kring detta beskriver hur flickor i behov av stöd missgynnas av både undervisningens utformning, relationen till läraren och behovet av att känna att man passar in. Forskningen i denna text beskriver hur elever i behov av stöd i högre grad än pojkar är beroende av ett fungerande samarbete och goda relationer för att nå skolframgång och hur flickors stödbehov uppmärksammas senare under skolgången. Resultatet visar att den forskning som finns till stor del är överensstämmande med de resultat som vår studie. Studiens resultat visar att flickorna känner att de av relationella skäl behöver dölja sina behov och att deras stödbehov ofta uppmärksammas sent under skolgången. Relationer spelar även en stor roll för flickornas motivation och möjlighet att klara sin skolgång. Däremot, i kontrast till det forskningen beskriver, berättar flickorna om hur stort ansvar de lägger på sig själva för att få stöd och att de ofta inte vet hur de kan påverka skolan och undervisningen för att möta sina behov även om de själva har kunskaper om hur de skulle vilja få stöd. Detta tyder på att kunskapen kring övergången mellan grundskola och gymnasium för flickor i behov av stöd är viktig för att kunna bidra till att flickor får sina stödbehov tillgodosedda under sin skolgång.

Background: The most common complaint of adults with hearing loss is understanding speech in noise. One class of masker that may be particularly useful in the assessment of speech-in-noise abilities is interrupted noise. Interrupted noise usually is a continuous noise that has been multiplied by a square wave that produces alternating intervals of noise and silence. Wilson and Carhart found that spondaic word thresholds for listeners with normal hearing were 28 dB lower in an interrupted noise than in a continuous noise, whereas listeners with hearing loss experienced only an 11 dB difference. Purpose: The purpose of this series of experiments was to determine if a speech-in- interrupted-noise paradigm differentiates better (1) between listeners with normal hearing and listeners with hearing loss and (2) among listeners with hearing loss than do traditional speech-in-continuous-noise tasks. Research Design: Four descriptive/quasi-experimental studies were conducted. Study Sample: Sixty young adults with normal hearing and 144 older adults with pure-tone hearing losses participated. Data Collection and Analysis: A 4.3 sec sample of speech-spectrum noise was constructed digitally to form the 0 interruptions per second (ips; continuous) noise and the 5, 10, and 20 ips noises with 50% duty cycles. The noise samples were mixed digitally with the Northwestern University Auditory Test No. 6 words at selected signal-to-noise ratios and recorded on CD. The materials were presented through an earphone, and the responses were recorded and analyzed at the word level. Similar techniques were used for the stimuli in the remaining experiments. Results: In Experiment 1, using 0 ips as the reference condition, the listeners with normal hearing achieved 34.0, 30.2, and 28.4 dB escape from masking for 5, 10, and 20 ips, respectively. In contrast, the listeners with hearing loss only achieved 2.1 to 2.4 dB escape from masking. Experiment 2 studied the 0 and 5 ips conditions on 72 older listeners with hearing loss, who were on average 13 yr younger and more varied in their hearing loss than the listeners in Experiment 1. The mean escape from masking in Experiment 2 was 7 dB, which is 20-25 dB less than the escape achieved by listeners with normal hearing. Experiment 3 examined the effects that duty cycle (0-100% in 10% steps) had on recognition performance in the 5 and 10 ips conditions. On the 12 young listeners with normal hearing, (1) the 50% correct point increased almost linearly between the 0 and 60% duty cycles (slope=4.2 dB per 10% increase in duty cycle), (2) the slope of the function was steeper between 60 and 80% duty cycles, and (3) about the same masking was achieved for the 80-100% duty cycles. The data from the listeners with hearing loss were inconclusive. Experiment 4 varied the interburst ratios (0, -6, -12, -24, -48, and -∞ dB) of 5 ips noise and evaluated recognition performance by 24 young adults. The 50% points were described by a linear regression (R2=0.98) with a slope of 0.55 dB/dB. Conclusion: The current data indicate that interrupted noise does provide a better differentiation both between listeners with normal hearing and listeners with hearing loss and among listeners with hearing loss than is provided by continuous noise.

The purpose of this study was to determine if performances on a 500 Hz MLD task and a word-recognition task in multitalker babble covaried or varied independently for listeners with normal hearing and for listeners with hearing loss. Young listeners with normal hearing (n = 25) and older listeners (25 per decade from 40-80 years, n = 125) with sensorineural hearing loss were studied. Thresholds at 500 and 1000 Hz were ≤30 dB HL and ≤40 dB HL, respectively, with thresholds above 1000 Hz <100 dB HL. There was no systematic relationship between the 500 Hz MLD and word-recognition performance in multitalker babble. Higher SoNo and SπNo thresholds were observed for the older listeners, but the MLDs were the same for all groups. Word recognition in babble in terms of signal-to-babble ratio was on average 6.5 (40- to 49-year-old group) to 10.8 dB (80- to 89-year-old group) poorer for the older listeners with hearing loss. Neither pure-tone thresholds nor word-recognition abilities in quiet accurately predicted word-recognition performance in multitalker babble.

Despite recent interest, there still is relatively little known about the ecology and physiology of diel and circadian rhythms in spiders. However, previous work on spiders suggests that there is a striking amount of variation in circadian period both among, and within, species, when compared to model organisms. Whereas previous studies of behavioral rhythms in spiders focused on females, here we describe the diel and circadian patterns of locomotor activity in male Parasteatoda tepidariorum (C. L. Koch, 1841) (Theridiidae). We found that the males showed mostly nocturnal activity under a light:dark cycle, with activity peaking very early after lights off and steadily declining to near zero just prior to lights on. Under constant darkness most individuals showed significant circadian rhythmicity with a mean free-running period of about 21.2 h. Though not the shortest average free-running period described for spiders, being so out of resonance with the 24 h solar day strains conventional circadian rhythm theory. Our data also suggest that the phase angle of entrainment for locomotor activity is in the mid-to-late photophase, but that activity may be masked by light. Of particular note is that both the diel and circadian activity patterns reported here for male P. tepidariorum are similar to those reported elsewhere for females of the species. This study deepens our understanding of the nature and variation in circadian rhythm in spiders and builds a case for further developing spiders as a model system for research integrating the fields of chronobiology and ecology.

Quand un stimulus visuel de haut contraste précède et puis succède à la présentation d'une cible de faible contraste à la même position, la cible peut devenir non-reconnaissable ou même non-détectable. Cet effet de masquage a été étudié en profondeur et beaucoup de ses paramètres sont bien définis. Mais en utilisant une nouvelle méthode avec une séquence de masques et de cibles en mouvement, il est maintenant possible de séparer de manière perceptuelle et attentionnelle la cible des masques tout en conservant l'ordre d'apparition des masques et de la cible à chaque endroit. Cette thèse utilise cette technique de stimuli en mouvement pour répondre à trois questions qui ne pourraient pas être résolu en utilisant une méthode de masquage conventionnelle. Dans la première série d'expériences on a testé si l'attention portée au masque influence l'impact de celle-ci sur la cible. Nous avons utilisé un écran où une séquence masque-cible-masque apparaît à une position puis à chaque 'frame' suivant elle apparaît à la position adjacente. Cette méthode permet à l'observateur de suivre attentionellement la cible sur son trajet, tout en évitant les masques distracteurs qui paraissent être à côté de la cible spatialement et non temporellement. Quand les masques sont efficaces, la position de la cible paraît être vide. Nous comparons l'efficacité du masquage quand l'attention n'est pas dirigée vers les masques, à l'efficacité du masquage quand l'attention ne peut pas éviter les masques, comme dans le masquage conventionnel. Nous n'avons trouvé aucune différence significative entre les deux conditions attentionnelles, ce qui indique que l'attention portée sur les masques ne module pas leur efficacité. Ensuite nous avons testé l'importance de l'espacement dans la séquence masque-cible-masque. Il n'y avait pas plus de masquage quand les espacements étaient réduits, ce qui suggère que le masquage n'est pas le résultat de masquage latéral ou de 'crowding' (encombrement spatial) aux distances testées. Enfin nous avons comparé la contribution de chaque masque: celui qui précède la cible (le pré-masque) et celui qui suit la cible (post-masque). Nous avons trouvé que le pré-masque génère la majorité de l'effet de masquage tandis que le post-masque a peu d'influence. Dans la seconde série d'expériences nous avons étudié ce qu'il advient du stimulus masqué. En baissant le contraste de la cible juste en dessous de son seuil de détection et en lui donnant une couleur saillante, nous avons découvert un stade intermédiaire où les caractéristiques ('features') de la cible sont reportées à la position d'un des masques. Avec une série d'expérience nous avons montré que la cible est intégrée avec le masque qui la suit directement et temporellement à la même position. Finalement nous avons étudié si un stimulus qui est masqué à un niveau invisible peut quand même exercer une influence sur une cible proche dans un arrangement de crowding. Nous avons comparé la détection d'une cible avec deux flankers (distracteurs adjacent) dans la zone de crowding, à la détection d'une cible quand les deux flankers sont masqué et que leur position paraît être vide. Pour conclure, la méthode de séquence en mouvement a révélé de nouvelles caractéristiques du masquage qui ne pouvaient pas être examinées en utilisant des techniques de masquage conventionnelles. Premièrement nous avons découvert que l'efficacité du masque est comparable que l'attention soit dirigée sur le masque ou non. Deuxièmement nous avons montré que les caractéristiques d'une cible qui est supprimée à sa position physique peuvent apparaître à la position du masque qui la suit temporellement. Et finalement, nous avons examiné l'effet de flankers masqués sur une cible dans un arrangement de crowding. / When high contrast visual stimuli precede and follow a low contrast target at the same location, the target may become unrecognizable and even undetectable. This masking effect has been extensively studied and many of its parameters are well characterized. However, using a new technique with a moving sequence of masks and targets it is now possible to perceptually and attentionally separate the target from the masks while retaining the same temporal order of masks and target at each location. This thesis exploits this moving stimulus technique to ask three questions that could not be addressed in standard masking paradigms. In the first series of experiments we looked at whether attention to the mask affected its impact on the target. We used a display where the mask-target-mask sequence appears at one location and on each subsequent frame it appears in the adjacent location. This allows observers to attentively track the target across locations without attending to the masks which appear perceptually adjacent in space rather than in time. When the masks are effective, the observer sees a blank space at the target location. We compare the effectiveness of this masking when the masks are unattended to the effectiveness when the masks are attended as in standard masking. We found no significant difference between the two attentional conditions suggesting that attention to the masks does not modulate their effectiveness. We next examined the importance of the spacing within the mask-target-mask sequences. There was no increase in the masking effect as spacing was reduced, suggesting that the masking was not a consequence of lateral masking or crowding at the spacings we tested. Finally, we compared the contributions of each mask individually: the one that preceded the target (pre-mask) and the one that followed (post-mask). We found that the pre-mask generated the majority of the masking effect while the post-mask was of little influence. In the second series of studies we investigated the fate of a masked stimulus. By lowering the target contrast just below its detection threshold and giving it a salient color, we found an intermediate, "lurking" stage where the target's features migrate to one of the mask locations. Through a succession of experiments we found that the target is integrated with the mask directly following it in time at the same location. Finally we looked at whether a stimulus that is masked to invisibility can still exert influence over nearby targets in a crowding array. We compared the detection of a crowded target with two flankers, compared to the detection of a target when the two adjacent flankers are masked so that their locations appear empty. In conclusion, the moving sequence technique revealed new characteristics of masking that could not be examined in standard masking paradigms. First, we found that the effectiveness of a mask was the same whether it is attended or not. Second, we showed that once a masked target has been suppressed from its physical location, its features can be found "lurking" at the location of the mask that follows the target in time. Finally, we examined the effect of masked flankers on a target in a crowding paradigm.

The present series of experiments were designed to investigate the utility of the use of a masking system to assess the development of stimulus control. The first experiment compares sample observing time with response accuracy in a match-to-sample task. The second experiment more closely examines this relation by subdividing the sample stimulus mask into four quadrants. The third experiment compares sample observing time during training with accuracy during a subsequent testing condition to determine if the observed differentiation between the quadrants was correlated with the development of stimulus control.

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Background: Malware is responsible for a significant part of the ever increasing cost of cyberattacks. Malware analysis is an important part in minimizing these costs. Because of the malicious nature of malware, it has to be executed in a safe and isolated environment during dynamic analysis to not cause harm to a live system, which is why Virtual Machines (VM) or Sandboxes are popular solutions. However, because malware developers actively try to evade analysis of their malware, some use, among other things, hardware attributes to reveal the environment as an analysis environment. Objectives: The aim of this thesis is to investigate which hardware attributes can be used to detect virtual environments and how they can be masked in the source code of hypervisors. Methods: We conducted a literature review to explore what indicators of virtual environments were already known. Then, we examined the known artifacts to see which artifacts can be used to reveal QEMU/KVM and VirtualBox. Using this information we tried to mask the artifacts on QEMU/KVM using values which do not indicate a virtual environment. To evaluate our masking strategy we conducted a controlled experiment.  Results: The literature review resulted in 72 unique artifacts related to hardware. Most of these unique artifacts are identifiers such as manufacturer and product name. We created an attribute collection script, designed to gather data from QEMU/KVM and VirtualBox on 58 out of the 64 unique hardware artifacts. This script was executed in multiple environments and the data gathered from each environment was compared with each other in order to filter out non-artifacts. This resulted in 40 revealing artifact devices and 26 registry keys for QEMU/KVM and 25 artifact devices and 13 registry keys on VirtualBox. Out of these we attempted to mask 25 devices and 22 keys. Our results showed that we had successfully masked 23 out of the 25 devices and all the registry keys. Conclusions: Our results show that most hardware artifacts can be masked and that our whitelist method is a viable strategy to accomplish that. / Bakgrund: Skadlig programvara står för en stor del av de ständigt ökande kostnaderna för cyberattacker. Analys av malware (skadlig programvara) är en viktig del för att minimera dessa kostnader. På grund av dess illasinnade natur måste malware köras i en säker och isolerad miljö under dynamisk analys för att inte orsaka skada på en fysisk maskin, vilket är anledningen till att virtuella maskiner (VM) eller sandlådor är en populära verktyg för analys av malware. Eftersom utvecklare av malware aktivt försöker undvika analys av sin skadliga programvara, använder de bland annat hårdvaruattribut för att avslöja miljön som en analysmiljö. Objectives: Syftet med denna uppsats är att undersöka vilka hårdvaruattribut som kan användas för att detektera virtuella miljöer och hur de kan maskeras i källkoden för hypervisors. Metoder: Vi genomförde en litteraturstudie för att utforska vilka indikatorer för virtuella miljöer som redan var kända. Sedan undersökte vi artefakterna som hittades under litteraturstudien för att se vilka som kan användas för att avslöja just QEMU/KVM och VirtualBox. Slutligen försökte vi maskera artefakterna på QEMU/KVM genom att ersätta dem med värden som inte avslöjar existensen av en virtuell miljö. För att utvärdera vår maskeringsstrategi genomförde vi sedan ett kontrollerat experiment. Resultat: Litteraturstudien resulterade i 72 unika artefakter relaterade till hårdvara. De flesta av dessa unika artefakter är identifierande strängar som tillverkare och produktnamn. Vi använde 58 av 72 unika artefakter i ett skript som vi använde för att samla in hårdvaruinformation från QEMU/KVM och VirtualBox. Det här skriptet kördes i flera miljöer och data som samlats in från varje miljö jämfördes med varandra för att filtrera bort attribut som inte avslöjar existensen av den virtuella miljön. Detta resulterade i 40 avslöjande enheter och 26 registernycklar för QEMU/KVM och 25 enheter och 13 registernycklar på VirtualBox. Av dessa försökte vi maskera 25 enheter och 22 nycklar. Våra resultat visade att vi framgångsrikt hade maskerat 23 av de 25 enheterna och samtliga registernycklar. Slutsatser: Våra resultat visar att de flesta avslöjande hårdvaruattribut kan maskeras och att vår maskeringsstrategi är en användbar metod för att åstadkomma det.