77 research outputs found
Critical Flow Calculations of Compressible Non-Ideal Fluids Based on an EOS
No full textThis thesis comprises the results of a graduation project which has been executed at the Laboratory of Applied Thermodynamics and Phase Equilibria, faculty of Chemical Engineering and Materials Science, Delft University of Technology (DUT). It is a part of a research project being carried out by Dr. L.Z. Boshkov and prof. J. de Swaan Arons; the project is financially sponsored by the Royal Dutch Shell Company. The aim of the research project is to present a systematic approach to the modelling and sizing of safety relief valves. Pressure or safety relief valves are routinely placed on chemical reactors and pressure vessels handling gases or liquids to protect the equipment against pressure build-up. Because the modelling still causes non-trivial tasks for chemical engineers, the research project was started to structurize the problems. In this work the results will be discussed with respect to t the critical flow of both one- and two-phase flow of non-ideal fluids through PRV 's at given stagnation states using an EOS. The results in this thesis are calculated for the non-ideal RK-fluid, however, the derived theories are presented as general as possible which makes extension to other EOS possible. The results in this thesis are calculated for the non-ideal RK-fluid, however, the derived theories are presented as general as possible which makes extension to other EOS possible. When concerning the one-phase flow calculations for the RK-fluid, one can conclude that the obtained results are equivalent to published results [Leung & Epstein, 1988]. In contrast to the latter published results, in this work an analytical maximization criterium is applied which provides more insight into the process equation which has to be used. Another important conclusion is that in this thesis the thermodynamic limits of one-phase critical flow are described and calculated. Both the spinodal and the saturation curve are indicated in the presented diagrams. The approach has been used to develop a new kind of phase diagrams: the critical flow phase diagrams (CFPD). This CFPD can be applied as an engineering tool in PRV design studies. With respect to the two-phase critical flow calculations, the well-known HEM have been worked out for non-ideal fluids using an EOS for the first time. Again an analytical maximization criterium has been applied to obtain the results. The results in this work are in a preliminary stage but one can conclude that they are in qualitatively correspondence with published data. On the face on it, the developed model can relatively easy be extended to critical flow processes which start in the one-phase region but have a maximum in mass flux in the two-phase region, and to processes concerning binary mixtures or even multi-component systems. When these extensions are succeeded, for the first time a general theory will have been derived that covers the entire range of initial vessel temperatures and pressures.Applied SciencesChemical Technology and Materials ScienceApplied Thermodynamics and Phase Equilibri
The Application of Ion Exchange Membranes in Chloride Related Electrochemical Technology
No full textApplied Science
Psychoeducation and online mood tracking for patients with bipolar disorder: A randomised controlled trial
No full textBackground: Psychoeducation is an effective adjunct to medications in bipolar disorder (BD). Brief psychoeducational approaches have been shown to improve early identification of relapse. However, the optimal method of delivery of psychoeducation remains uncertain. Here, our objective was to compare a short therapist-facilitated vs. self-directed psychoeducational intervention for BD. Methods: BD outpatients who were receiving medication-based treatment were randomly assigned to 5 psychoeducation sessions administered by a therapist (Facilitated Integrated Mood Management; FIMM; n=60), or self-administered psychoeducation (Manualized Integrated Mood Management; MIMM; n=61). Follow-up was based on patients' weekly responses to an electronic mood monitoring programme over 12 months. Results: Over follow-up, there were no group differences in weekly self-rated depression symptoms or relapse/readmission rates. However, knowledge of BD (assessed with the Oxford Bipolar Knowledge questionnaire (OBQ)) was greater in the FIMM than the MIMM group at 3 months. Greater illness knowledge at 3 months was related to a higher proportion of weeks well over 12 months. Limitations: Features of the trial may have reduced the sensitivity to our psychoeducation approach, including that BD participants had been previously engaged in self-monitoring. Conclusions: Improved OBQ score, while accelerated by a short course of therapist-administered psychoeducation (FIMM), was seen after both treatments. It was associated with better outcome assessed as weeks well. When developing and testing a new psychosocial intervention, studies should consider proximal outcomes (e.g., acquired knowledge) and their short-term impact on illness course in bipolar disorder
Why Do Babies Cry: Once Again About Egoism and Altruism
No full textThe article deals with a ratio between egoistic and altruistic components in a person’s motivation and activity. The author provides new interpretations for the widely known examples of altruistic behavior. The results of experimental investigations discovering positive correlations, which exist between egoism and altruism in a person’s daily activity, are quoted. The author touches upon the problem of egoism as a new possible subject of psychology. The incorporation of egoism concept into the structure of modern humanitarian science opens new perspectives for theorizing and experimental investigation
A Macro-Micro-Symbolic Teaching to Promote Relational Understanding of Chemical Reactions
No full textThe purpose of this research is threefold: (1) to identify the difficulties that Grade 10 students in a Lebanese school have that hinder their conceptual understanding at the micro-macro-symbolic interface in chemistry, (2) to investigate the effect of a macro-micro-symbolic teaching approach on students' relational understanding of chemical reactions, and (3) to characterize students' conceptual profiles regarding their understanding of chemical reactions in terms of macro, micro, symbolic levels and the relations among them, at the end of the teaching sequence. Forty six 10th graders from two sections participated in the study. A student-centered approach was followed in both sections based on constructivist pedagogy. Hence the teacher played the role of a facilitator who guided students in a meaning making inductive learning process, through questioning, monitoring, validating, and clarifying ideas. Instruction in the experimental group was characterized by macro-micro-symbolic teaching that focuses on the interplay between the levels, integrates various representations, and engages students in an epistemic discourse about the nature of knowing in chemistry. Data sources for the study included a pre-test and two post-intervention tasks: a post-test and a concept map task, in addition to interviews with selected students from both sections. Findings indicated that macro-micro-symbolic teaching enhanced students' conceptual understanding and relational learning of chemical reactions. Besides, four assertions related to students' conceptual and epistemological thinking in response to the different teaching approaches are presented. Implications for instruction and for teacher education programs, as well as recommendations for further research, are discussed in light of these findings. © 2012 Copyright Taylor and Francis Group, LLC.Ahtee M, 1998, INT J SCI EDUC, V20, P305, DOI 10.1080-0950069980200304; Andersson B. R., 1990, RELATING MACROSCOPIC, P12; Ben-Zvi R., 1990, RELATING MACROSCOPIC, P183; Bodner G. M., 2000, U CHEM ED, V4, P24; Brosnan T., 1990, RELATING MACROSCOPIC, P198; Brosnan T., 2001, RES SCI TECHNOLOGICA, V19, P69; Cakmakci G, 2006, INT J SCI EDUC, V28, P1795, DOI 10.1080-09500690600823490; Chi M., 1992, COGNITIVE MODELS SCI, P129; Chi MTH, 2005, J LEARN SCI, V14, P161, DOI 10.1207-s15327809jls1402_1; Cokelez A., 2007, INT J SCI ED, V30, P806; Dori J. Y., 2003, J RES SCI TEACH, V40, P278; Duit R., 2006, BIBLIO STCSE TEACHER; Gabel D., 1998, INT HDB SCI ED, P233; Georgiadou A., 2000, CHEM EDUC RES PRACT, V1, P217; Crespo MAG, 2004, INT J SCI EDUC, V26, P1325, DOI 10.1080-0950069042000205350; Hinton M. E., 1999, CHEM ED, V4, P158, DOI 10.1007-s00897990325a; Hofstein A., 2004, CHEM EDUC RES PRACT, V5, P301; Horton C, 2001, STUDENT PRECONCEPTIO; Johnson P, 2002, INT J SCI EDUC, V24, P1037, DOI 10.1080-09500690110095339; Johnstone A. H., 2000, CHEM EDUC RES PRACT, V1, P9; JOHNSTONE A. H., 1982, SCH SCI REV, V64, P377; Johnstone A. H., 1991, Journal of Computer Assisted Learning, V7, DOI 10.1111-j.1365-2729.1991.tb00230.x; Justi R., 2002, CHEM ED RES BASED PR, P47; Kind V, 2004, APPEARANCE STUDENTS; Kozma RB, 1997, J RES SCI TEACH, V34, P949, DOI 10.1002-(SICI)1098-2736(199711)34:9949::AID-TEA73.0.CO;2-U; Laugier A., 2000, CHEM EDUC RES PRACT, V2, P57; Mulford R. D., 1996, INVENTORY MEASURING; NAKHLEH MB, 1992, J CHEM EDUC, V69, P191; Novak J. D., 1984, LEARNING LEARN; Paradis J., 2007, EXPLORATIONS CONCEPT; RuizPrimo MA, 1996, J RES SCI TEACH, V33, P569, DOI 10.1002-(SICI)1098-2736(199608)33:6569::AID-TEA13.0.CO;2-M; Russell JW, 1997, J CHEM EDUC, V74, P330; Salloum S. L., 2000, THESIS AM U BEIRUT B; Sequeira M., 1990, RELATING MACROSCOPIC, P220; Stavridou H, 1998, INT J SCI EDUC, V20, P205, DOI 10.1080-0950069980200206; Taber K., 2002, CHEM MISCONCEPTIONS, V2; Taber K., 2002, CHEM MISCONCEPTIONS; Treagust DF, 2003, INT J SCI EDUC, V25, P1353, DOI 10.1080-0950069032000070306; Tsaparlis G. R., 2000, CHEM EDUC RES PRACT, V1, P161, DOI [10.1039-A9RP90017A, DOI 10.1039-A9RP90017A]38
The Many Faces of Design
No full textIn light of contemporary global pressures, designers have been considering how to apply their thinking and practice more broadly within the enterprise of sustainability. Given the often wicked nature and cross-scale dynamics of related challenges, there is reason to reassess the role of design in processes of systems transformation amidst complexity. In this manuscript, the author contemplates the diversity of ‘designerly ways’, in interpretation of designers’ encounters with complex adaptive systems. These interactions are classified here using the three lenses of adaptive response, creative agency and emergent engagement
Poem of Abu Bakr Qalandar Rumi “Qalandar-name” as a source of information on Sufi ritual music
No full textThis paper is devoted to analyze the text of Abu Bakr Qalandar Rumi’s poem “Qalandar-name” from the point of view of describing the Sufi ritual of listening to sama`. As it is known, Sufi zikr can be two types – “loud”, with singing, dancing movements and playing musical instruments, and “quiet” without any musical part.
Research materials: The statement of the author of the poem is of scholarly interest because the author welcomes both two types of zikr, as his Ushshaki group used singing, dancing and musical instruments. All these activities were used for the sole purpose of unity with the divine. The text of the poem is a source on Sufi rituals and their musical peculiarities in different tariqats. The poet also provides theoretical justifications for the permissibility of music in Sufi rituals, based on famous Sufi sheikhs of the earlier centuries.
Also the author of the poem displays a deep knowledge of the general Sufi Islamic culture of his time, often referring to poetic images of famous Sufi poets of different countries. The musical instruments presented in the poem give a deep insight into the fact that each group of dervishes may have had their own set of instruments and their own dances. A common genre for all Sufi groups in the world is the genre of munajat, which appears four times in the poem as a separate prayer chapter.
Results and novelty of the study: In this paper much attention is paid to the analysis of Sufi musical genres and instruments which were typical of that era. Also a number of the most favorite musical instruments are identified, which were widely used during the Sufi ritual of listening to sama`. The differences between the terms sama` (Sufi listening ritual) and the dance genre of Crimean Tatars “sema” and Tajik “samo” are explained separately. The musical instruments, such as arganun and organ, as well as musikar / musigar, which have different descriptions in historical and modern scientific literature, are also studied separately. The description of the organ in the context of the poem together with the image of the immortal bird Kuknus / Phoenix gives the readers the poem the image about two variants of the wind instrument – the Pan flute type and the keyboard type with mechas. Since we have not found a precise description of the organ and the arganun / musikar in the poem itself, this question remains open for future research. The poem “Kalandar-nameh” will no doubt be useful as a source on Sufi culture of different tariqats of the Middle Ages
Investigation of basic notions of positive psychology with an aid of Experience Sampling Method (ESM)
No full textThe article deals with two investigations of the main concepts of the contemporary positive psychology (eudaimonia, hedonism, the flow, happiness and unhappiness) with the help of ESM. The studies were built upon Person-Oriented Conception of Happiness (POCH) elaborated by the author. The results indicate that the flow can be accompanied by the rise of the other «components of happiness» belonging to other theories. The study of the situations, that were associated with «unhappiness», showed that most of them belong to maintenance activities of the individual
The Many Faces of Design
No full textIn light of contemporary global pressures, designers have been considering how to apply their thinking and practice more broadly within the enterprise of sustainability. Given the often wicked nature and cross-scale dynamics of related challenges, there is reason to reassess the role of design in processes of systems transformation amidst complexity. In this manuscript, the author contemplates the diversity of ‘designerly ways’, in interpretation of designers’ encounters with complex adaptive systems. These interactions are classified here using the three lenses of adaptive response, creative agency and emergent engagement.In light of contemporary global pressures, designers have been considering how to apply their thinking and practice more broadly within the enterprise of sustainability. Given the often wicked nature and cross-scale dynamics of related challenges, there is reason to reassess the role of design in processes of systems transformation amidst complexity. In this manuscript, the author contemplates the diversity of ‘designerly ways’, in interpretation of designers’ encounters with complex adaptive systems. These interactions are classified here using the three lenses of adaptive response, creative agency and emergent engagement
Floating breakwaters: State of the art, literature review
No full textA multitude of conceptual models of floating breakwaters have been proposed without extensive or complete evaluation of most of these concepts. The technical literature regarding floating breakwater applicability and design procedures is fragmentary and sometimes confusing. Clear, concise guidance does not always exist for those responsible for planning and developing wave protection measures which utilize floating breakwaters. This study reviewed and evaluated the existing technical literature (theoretical, field, and laboratory) on floating breakwater concepts. While floating breakwaters provide a lesser assurable degree of protection than a permanently fixed breakwater, they are in general less expensive and can be moved from one location to another. The cost of a floating system is only slightly dependent on ,.,rater depth and foundation conditions. Adequate wave reduction or energy attenuation can be attained by a floating breakwater only if the incident wave is of a relatively low height. A reasonable magnitude appears to be an incident wave height not exceeding 4 feet, with a corresponding wave period not exceeding 4 seconds. Floating breakwaters can attenuate waves with these incident characteristics to a magnitude tolerable in a small-craft mooring area (wave heights up to 1.5 feet). Open-ocean applications of a distinctly different concept can be formulated to withstand substantial increases in the incident wave characteristics. A group of prismatic structures contains the simplest forms of floating breakwaters. This group offers the best possibilities for multiple use as walkways, storage, boat moorings, and fishing piers. In addition to mass, the radius of gyration and the depth of submergence appear to significantly influence the attenuation characteristics. As the ratio of breakwater width-to wavelength increases to values greater than 0.5, the wave attenuation features of the structure not only improve markedly, but the net result of the forces on the mooring and anchoring system becomes substantially less. This occurs because the wave dynamics are exerting forces on a part of the structure in a direction opposite to those forces on other parts of the breakwater
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