Design, Assembly, and Assessment of an Experimental Apparatus to Measure Fouling of Condenser Tubes

This thesis discusses the design, construction, and debugging of an experimental apparatus to measure fouling in smooth and/or augmented copper alloy condenser tubes. In addition, guidelines and recommendations are made for construction of similar devices. Specification sheets of the system components, detailed design calculations, and photographs of the apparatus are included in the appendices

A technical note on application of internally finned tubes in solar parabolic trough absorber pipes

The heterogeneous incoming heat flux in solar parabolic trough absorber tubes generates huge temperature difference in each pipe section. Helical internal fins can reduce this effect, homogenising the temperature profile and reducing thermal stress with the drawback of increasing pressure drop. Another effect is the decreasing of the outer surface temperature and thermal losses, improving the thermal efficiency of the collector. The application of internal finned tubes for the design of parabolic trough collectors is analysed with computational fluid dynamics tools. Our numerical approach has been qualified with the computational estimation of reported experimental data regarding phenomena involved in finned tube applications and solar irradiation of parabolic trough collector. The application of finned tubes to the design of parabolic trough collectors must take into account issues as the pressure losses, thermal losses and thermo-mechanical stress, and thermal fatigue. Our analysis shows an improvement potential in parabolic trough solar plants efficiency by the application of internal finned tubes

Analysis of internal helically finned tubes for parabolic trough design by CFD tools

This paper has analysed the effect of the utilization of internal finned tubes for the design of parabolic trough collectors with computational fluid dynamics tools. Our numerical approach has been qualified with the computational estimation of reported experimental data regarding phenomena involved in finned tube applications and solar irradiation of parabolic trough collector. The application of finned tubes to the design of parabolic trough collectors must take into account features as the pressure losses, thermal losses and thermo-mechanical stress and thermal fatigue. Our analysis shows an improvement potential in parabolic trough solar plants efficiency by the application of internal finned tubes

Uwarunkowania parentyfikacji doświadczanej w dzieciństwie i okresie dorastania z perspektywy młodych dorosłych

Parentification has also been known and studied as role reversal in family. Despite the fact that this concept entered scientific literature in the 1970’s, it has not received adequate attention and its causes and mechanisms have not been fully established. In Poland, parentification has been on the margins of psychological research and its prevalence, causes, and effects are unknown. Consequently, there is lack of practical guidelines for practitioners working with families in which role reversal might have taken place. The goal of this study is to gain insight into the prevalence, conditions, and types of parentification retrospectively reported by young adults reflecting on their family experiences in childhood and adolescence. The participants were 1045 students studying towards various teaching degrees at the University of Opole (Uniwersytet Opolski) and University of Szczecin (Uniwersytet Szczecinski). The results indicate that that parentification (or role reversal) correlates with selected sociodemographic variables, negative family life events, and with characteristics and patterns of behavior of the parents. Prevalence of parentification has also been revealed: over 70% of participants reported experiencing instrumental or emotional parentification whereas one fourth experienced a sense of injustice related to being parentified.Parentyfikacja to termin najczęściej zamiennie określany jako odwrócona rola w rodzinie. Mimo że pojęcie to do literatury naukowej weszło już w latach 70., jest to obszar zaniedbany naukowo, którego zarówno przyczyny, jak i mechanizmy powstania nie zostały gruntownie przebadane. W Polsce parentyfikacja opisywana jest marginalnie, nieznana jest ani skala zjawiska, ani jej uwarunkowania oraz konsekwencje. Brakuje również praktycznych wskazań do pracy z rodzinami, w których dochodzi do odwróconej roli rodzicielskiej. Celem przeprowadzonych badań było poznanie skali zjawiska, uwarunkowań parentyfikacji w dzieciństwie i okresie dorastania, jej rodzajów doświadczanych przez młodych dorosłych. W badaniu udział wzięło 1045 studentów, kierunków pedagogicznych Uniwersytetów Opolskiego i Szczecińskiego. W wyniku otrzymanych rezultatów z badań stwierdzono, że parentyfikacja, czyli odwrócona rola rodzicielska, koreluje z wybranymi czynnikami socjodemograficznymi, niekorzystnymi zdarzeniami losowymi w rodzinie oraz cechami i zachowaniami rodziców. Wyniki wskazują również na powszechność zjawiska: ponad 70% badanych doświadczyło parentyfikacji instrumentalnej bądź emocjonalnej, podczas gdy jedna czwarta doświadczyła poczucia krzywdy związanego z byciem parentyfikowanym

How groups react to disloyalty in the context of intergroup competition: Evaluations of group deserters and defectors

Groups strongly value loyalty, especially in the context of intergroup competition. However, research has yet to investigate how groups respond to members who leave the group or join a competing outgroup. Three studies investigated groups' reactions to defectors (Experiment 1) and deserting members (Experiments 2 and 3). Experiment 1 used a minimal group paradigm to demonstrate that defectors trigger a stronger derogation of ingroup deviants than outgroup deviants vis-à-vis normative members. Experiments 2 and 3 compared group members' responses to defection versus desertion from minimal and self-assigned groups, respectively. Experiment 3 also explored an explanation for the evaluations of disloyalty. Across studies, participants evaluated normative ingroup members more positively than defectors and deserters. Outgroup deserting and defecting members were evaluated similarly. Derogation of ingroup as compared to outgroup targets emerged only for defectors. In addition, Experiment 3 demonstrated that negativity toward the outgroup was related to stronger derogation of disloyal targets. Negative outgroup attitudes trigger stricter criteria for responding to disloyalty. Directions for future research are discussed

Explaining lifelong loyalty: The role of identity fusion and self-shaping group events

Pledging lifelong loyalty to an ingroup can have far-reaching behavioural effects, ranging from ordinary acts of ingroup kindness to extraordinary acts of self-sacrifice. What motivates this important form of group commitment? Here, we propose one especially potent answer to this question–the experience of a visceral sense of oneness with a group (i.e., identity fusion). In a sample of British football fans, a population in which high levels of lifelong loyalty are thought to be common, we first examined the hypothesised relationship between fusion and perceptions of lifelong loyalty to one’s club. We further explored the hypothesis that fusion and lifelong loyalty are not merely a reflection of past time investment in a group, but also reflect a deeper, memory-based process of feeling personally shaped by key group events, both euphoric and dysphoric. We found broad support for these hypotheses. Results suggest that feeling personally self-shaped by club events (e.g., crucial wins and losses), rather than time invested in the club, leads to greater identity fusion to one’s club. In turn, fusion engenders a sense of lifelong club loyalty. We discuss our findings in relation to the growing literature on the experiential origins of intense social cohesion

NCAM regulates temporal specification of neural progenitor cells via profilin2 during corticogenesis

The development of cerebral cortex requires spatially and temporally orchestrated proliferation, migration, and differentiation of neural progenitor cells (NPCs). The molecular mechanisms underlying cortical development are, however, not fully understood. The neural cell adhesion molecule (NCAM) has been suggested to play a role in corticogenesis. Here we show that NCAM is dynamically expressed in the developing cortex. NCAM expression in NPCs is highest in the neurogenic period and declines during the gliogenic period. In mice bearing an NPC-specific NCAM deletion, proliferation of NPCs is reduced, and production of cortical neurons is delayed, while formation of cortical glia is advanced. Mechanistically, NCAM enhances actin polymerization in NPCs by interacting with actin-associated protein profilin2. NCAM-dependent regulation of NPCs is blocked by mutations in the profilin2 binding site. Thus, NCAM plays an essential role in NPC proliferation and fate decision during cortical development by regulating profilin2-dependent actin polymerization

Heat Transfer and Friction in Helically-Finned Tubes using Artificial Neural Networks

The last few decades have seen a significant development of complex heat transfer enhancement geometries such as a helicallyinned tube. The arising problem is that as the fins become more complex, so does the prediction of their performance. In addition to discussing existing prediction tools, this dissertation demonstrates the successful use of artificial neural networks as a correlating method for experimentally- measured heat transfer and friction data of helicallyinned tubes