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This research presents a comprehensive review of solar chimney power plants (SCPP) as a reliable source of renewable electricity generation. Solar chimney power plants differ from other renewable energy technologies because thermal and momentum effects result in 24-h electricity generation. However, they are influenced by a wide range of design, geometrical and operational parameters, and environmental conditions. This review evaluates the design aspects and the theoretical, numerical, experimental, and performance findings in previous works holistically and concisely. The study also extensively discusses the various optimization strategies, advantages, disadvantages, and limitations of solar chimney power plants. Energy storage aspects and hybrid system designs are also addressed in the present review in order to overcome the known handicaps and limitations of solar chimney power plants. The performance figures of the technology are clearly demonstrated as a function of the design and operational conditions, and future prospects are discussed in detail. It is hoped that designers and policymakers will gain valuable insight into the technological features and advancements of solar chimney power plants, assisting them in making a better-informed decision.

Facial marks have been studied before, either as a complement to face recognition systems or for their suitability as a single biometric modality. In this paper, we use a subset of the FRGCv2 data set (12307 images and 568 subjects) to study the properties of facial marks, their spatial patterns, and classifiers acting upon these patterns. We observe differences between age and ethnic groups in the number of facial marks. Also, facial marks tend to be clustered. We present six forensically relevant aspects with respect to the design and evaluation of classifiers. These aspects help to systematically study factors that influence performance characteristics (discriminating power and calibration loss) of these classifiers. Calibration loss is of particular forensic importance; it essentially measures how well the classifier output can be used as strength of evidence in a court of law. We use various facial mark grids to which the facial mark spatial patterns are assigned. We find that a classifier that utilizes the facial mark grid of a specific subject outperforms all other classifiers. We also observe that the calibration loss of such subject-based classifier indicates that small grid cell sizes should be avoided.

Purpose: Vacation house,a part of Sweden ́s history that decreases annually, mainly because existing vacation houses are being extended and permanented and few new ones are being built. One reason why many vacation houses are permanented is that the detailed development plan for the area is insufficient or missing to maintain the area as a vacation house area. In addition to the detailed development plan there is other legislation that is followed at building permits. For vacations houses there is no regulation in the legislation which causes difficulties for building permit management for individuals and authorities. The aim of the survey is to gather material with the aim to establish a definition of vacation houses into the legislation. Method: The survey is conducted as a qualitative study with semi-structured interviews with nearby municipalities building permit departments, equal in size as Jönköping's municipality and with smaller municipalities. The material from the semi-structured interviews was compared and strengthened with document analysis from previous research. The document analysis has reviewed previous researches, studies, judiciary, books and detailed development plans. Findings: The result shows that a definition of vacation houses should be legislated in Plan- och bygglagen and can be applied by Boverket’s building regulations with a clearer explanation of vacation houses. To give municipalities common ground to emanate from to preserve the nature of vacations house areas. How the vacations house areas should be designed and how their design can be preserved is most suitable in the detail development plan. It is in the detail development plan the area of a vacation home can be limited. If the area of the vacation homes is limited, the survey show that it will result in that fewer vacation homes are permanentized as the conveniences which permanent homes require will not fit. Implications: The results of the survey can be used to give municipalities an understanding of how building permits of vacation houses ́ are currently handled by other municipalities. The study contributes with improvement proposals for detailed development plan in the municipality of Jönköping. The conclusion of the result is that a more comprehensive study should be conducted to include municipalities throughout Sweden to ultimately lead to a joint definition for vacation houses.Limitations: The result is based on interviews with six municipalities and document analysis. A more comprehensive survey can interview more municipalities throughout Sweden to obtain a more generalized result, as well as to include authorities such as county administrative boards and Boverket. In a more comprehensive survey, more methods can be used as observations for better understanding of building permit handling of vacation homes and surveys to be able to reach out to all municipalities in Sweden. Syfte: Fritidshusen, en del av Sveriges historia som minskar årligen, främst på grund av att befintliga fritidshus byggs till och permanentas samt att det byggs få nya. En anledning till att många fritidshus permanentas är att detaljplanen för ett område är otillräcklig eller saknas för att behålla området som ett fritidshusområde. Förutom detaljplan är det övrig lagstiftning som följs vid bygglov. För fritidshus saknas en definition i lagstiftningen vilket medför svårigheter för bygglovhantering för privatpersoner och myndigheter. Syftet med studien är att ta fram material som kan utnyttjas för att införa en definition av fritidshus i lagstiftning. Metod: Undersökningen genomförs som en kvalitativ studie med semi-strukturerade intervjuer med närliggande kommuners bygglovsavdelningar, både i jämnstorlek med Jönköpings kommun och med mindre kommuner. Materialet från de semi-strukturerade intervjuerna bearbetades sedan genom att jämföras och stärkas med litteraturstudie från tidigare forskning. Litteraturstudien har granskat tidigare undersökningar, studier, domar, böcker och detaljplaner. Resultat: Resultatet visar att en definition utav fritidshus bör lagstiftas i plan- och bygglagen och kan tillämpas av Boverket med en tydligare förklaring till fritidshus. Detta för att ge kommuner en grund att utgå ifrån för att bevara fritidshusområdens karaktär. Hur fritidshusområden ska utformas och hur dess karaktär kan behållas görs lämpligast i detaljplaner. Det är även i detaljplanen ytan kan begränsas för ett fritidshus. Begränsas ytan för ett fritidshus visar undersökningen att färre fritidshus kommer permanentas då de bekvämligheter en permanentbostad bör ha inte kommer att rymmas. Konsekvenser: Undersökningens resultat kan användas för att ge kommuner förståelse för hur bygglov av fritidshus hanteras i dagsläget av andra kommuner. Studien bidrar med förbättringsförslag för detaljplaner i Jönköpings kommun. Slutsatsen av resultatet är att en mer omfattande studie bör genomföras för att inkludera kommuner inom hela Sverige för att i slutändan utmynna till en gemensam definition för fritidshus. Begränsningar: Resultatet är baserat på intervjuer med sex kommuner och litteraturstudier. En mer omfattande undersökning kan intervjua fler kommuner över hela Sverige för att få ett mer generaliserbart resultat, samt att inkludera myndigheter som länsstyrelser och Boverket. I en mer omfattande undersökning kan fler metoder tillämpas som observationer för bättre förståelse av bygglovshantering av fritidshus och enkäter för att nå ut till alla kommuner i Sverige.

Smart-Home-Assistenten wie Amazon Alexa und Google Home werden derzeit üblicherweise für nicht-vertrauliche oder nicht-sicherheitsrelevante Tätigkeiten wie Wetterberichtabfragen oder die Steuerung verknüpfter Geräte verwendet. In ausgewählten Märkten sind jedoch bereits sicherheitskritische Anwendungsfälle wie Online-Banking und sprachgesteuerte Türschlösser verfügbar, welche mit zunehmender Beliebtheit in Zukunft weitere Verbreitung finden werden. Dabei sind grundlegende Sicherheitsfunktionen erforderlich, um das Vertrauen der AnwenderInnen zu stärken. Derzeit besteht der Stand der Technik der Authentifizierung für Smart-Home-Assistenten aus unsicheren Sprachcodes, welche von BenutzerInnen laut ausgesprochen werden müssen, sowie biometrischer Authentifizierung mittels Stimmerkennung. Für diese Authentifizierungsmethoden wurde in der Vergangenheit eine Reihe von Angriffen demonstriert. Frühere Arbeiten legen es außerdem nahe, dass die Übernahme neuer, sicherheitskritischer Funktionen von fehlendem Vertrauen der BenutzerInnen in das System behindert werden könnte. Deshalb untersuchen wir den Design-Space für zukünftige Authentifizierungsmechanismen. Diese haben das Potenzial stärkere Sicherheitseigenschaften aufgrund gesteigerter Benutzerfreundlichkeit zu erzielen, sowie den BenutzerInnen ein gestärktes Sicherheitsgefühl während der Ausführung von Anwendungen geben zu können. Wir führen semi-strukturierte Interviews mit BenutzerInnen von Amazon Alexa durch, in welchen vier sicherheitskritische Szenarien behandelt werden. In jedem Szenario befragen wir die TeilnehmerInnen nach ihrer Wahrnehmung bezüglich Bedrohungen, Schutzmaßnahmen sowie für ihr Sicherheitsempfinden wesentliche Designaspekte. Unsere Erkenntnisse, welche wir aus einer thematischen Analyse der Daten gewonnen haben, zeigen u. a., dass BenutzerInnen (1) primär besorgt sind über umstehende Zuhörer, (2) wenig Vertrauen in ausgesprochene Codes haben und stattdessen vertrauenswürdige Stimmerkennung bevorzugen würden, und (3) kontextabhängige Anforderungen an Authentifizierungssysteme haben, speziell in Abhängigkeit von Ort und Anwesenheit anderer Personen. Die von uns bereitgestellten Designempfehlungen können die Basis für hochentwickelte zukünftige Authentifizierungsmechanismen bilden., Smart home assistants such as Amazon Alexa and Google Home are currently usually used for non-confidential or non-security-sensitive activities such as checking the weather report or for controlling linked devices. In selected markets, security-critical applications such as online banking and voice-controlled door locks are already available and will become more widespread in the future as their popularity increases. Basic security functions are required to strengthen users' confidence. At the moment, state-of-the-art authentication for smart home assistants consists of insecure voice codes that users have to utter out loud, as well as biometric authentication using voice recognition. A number of attacks have been demonstrated for these authentication methods in the past. Previous work also indicates that the adoption of new, security-critical functions could be hindered by a lack of user confidence in the system. We are, therefore, examining the design space for future authentication mechanisms. These have the potential to achieve stronger security properties due to increased usability and give users a stronger feeling of security during the execution of applications. We carry out semi-structured interviews with Amazon Alexa users, in which four security-critical scenarios are dealt with. In each scenario, we ask the participants about their perception of threats, mitigation strategies, and design aspects essential for their perception of security.Our findings, which we have gained from a thematic analysis of the data, show amongst others that users (1) are primarily concerned about bystanders, (2) have little trust in spoken codes and would instead prefer trustworthy voice recognition, and (3) have context-dependent requirements for authentication systems, especially depending on the location and presence of other people. The design recommendations we provide can form the basis for highly developed future authentication mechanisms.

Syftet med studien är att presentera ett designkoncept för publika diskussioner på nätet med målet att uppnå djupare diskussioner och minska mängden information overload. Arbetet använder metoden Concept Driven Interaction Design (CDID) som går ut på att skapa ett designkoncept utifrån flera olika teorier som appliceras genom interaktionsdesign. Ett designkoncept innehåller tre delar: ett namn, ett syfte och huvudprinciper. CDID innehåller sju steg som arbetet är utformat efter: 1. Concept Generation – Summeras i en tabell som jämför diskussioner i forum (med flera antagande) och diskussioner med hjälp av metoden Philosophy for Children (P4C), samt annan teori. 2. Concept Exploration – Åtta olika designaspekter identifieras utifrån jämförelsetabellen. 3. Internal Concept Critique – Designaspekterna jämförs med två snarlika diskussionsformat. 4. Design of Artifacts – Designkoncept version 1 skapas. 5. External Design Critique – Intervjuer utförs för att undersöka intervjupersonerna generella erfarenheter av online diskussioner, testar antagandena från jämförelsetabellen och ge direkt feedback på första versionen av designkonceptet. 6. Concept Revisited – Ändringar görs baserat på intervjumaterial och direkt feedback. 7. Concept Contextualization – Designkonceptet kopplas tillbaka till litteraturen. Studien resulterar i ett designkoncept kallat CoFramer och stödjer dessa huvudprinciper som ställs i kontrast till material som identifierats genom intervjuerna: Tabell 1: CoFramers huvudprinciper och faktorer från intervjuer om diskussioner på forum. CoFramers huvudprinciper | Från intervjuer om diskussioner på forum Strukturerad början och slut | Diskussion utan tydligt slut Begränsat antal deltagare | Stor mängd deltagare Minimum antal deltagare | Många inaktiva åskådare Explicita deltagare | Lite information om deltagare Gemensamma förutsättningar | Otydlighet kring deltagares förutsättningar Begränsad informationstäthet per inlägg | Långa inlägg och/eller snabba inlägg Den röda tråden och parallella trådar | Oftast parallella trådar Aktiv samtalsledare | Outredda missförstånd Studien indikerar på att CoFramer bör resultera i mer strukturerade diskussioner och som utsätter användaren för en lägre mängd information overload och mindre grounding cost jämfört med vad som vanligtvis uppstår i publika diskussioner online. The focus of this essay is to develop a design concept for online public discussions with deep discussions and low information overload. The method used is Concept Driven Interaction Design (CDID) which involves constructing a design concept by applying a variety of theories in tangible interaction design. A design concept has three basic parts: a name, high-level goals and outlines generic principles. CDID includes seven steps which is used in this work: 1. Concept Generation – Formatted into a table that compare forum discussion (with several hypothesis) compared to discussions with the method Philosophy for Children (P4C) and other theories. 2. Concept Exploration – Eight distinct design aspects are identified from the comparison table. 3. Internal Concept Critique – The design aspects are compared to three similar discussion formats. 4. Design of Artifacts – Design concept version 1 is created. 5. External Design Critique – Interviews are conducted to explore their general experience of online discussions, investigate the hypothesis from the comparison table and to seek direct feedback on the first draft of the design concept. 6. Concept Revisited – Changes are made to the design concept based on the interview material and the direct feedback. 7. Concept Contextualization – The design concept is related to the original literature. The result of the study is a design concept named CoFramer. CoFramer’s generic principles are summarized and contrasted against factors identified from the interview material in this table: Tabell 2: CoFramer’s generic principles and interviews about online discussions. CoFramer’s generic principles | From interview material on forum discussion Organized start and ending | Discussions without clear ending Limited number of participants | Large number of participants Minimum number of participants | Large number of inactive spectators Explicit participants | Low information about participants Common conditions | Vagueness in participants conditions Limited information density per post | Long posts and/or fast posts The red thread and parallel threads | Often parallel threads Active facilitator | Unresolved misunderstandings The study indicates that CoFramer would create more structured discussions with a lower amount of information overload and less grounding cost compared what normally arise in public online discussions.

Inform plays a very important role in life and nowadays, the world largely depends on the World Wide Web to obtain any information. Web comprises of a lot of websites of every discipline, whereas websites consists of web pages which are interlinked with each other with the help of hyperlinks. The success of a website largely depends on the design aspects of the web pages. Researchers have done a lot of work to appraise the web pages quantitatively. Keeping in mind the importance of the design aspects of a web page, this paper aims at the design of an automated evaluation tool which evaluate the aspects for any web page. The tool takes the HTML code of the web page as input, and then it extracts and checks the HTML tags for the uniformity. The tool comprises of normalized modules which quantify the measures of design aspects. For realization, the tool has been applied on four web pages of distinct sites and design aspects have been reported for comparison. The tool will have various advantages for web developers who can predict the design quality of web pages and enhance it before and after implementation of website without user interaction.

La programación colaborativa, o programación en par, es una de las áreas más estudiadas actualmente debido a su impacto en el proceso de desarrollo de software. El propósito de la presente investigación consistió en determinar los aspectos básicos de diseño que un entorno de programación colaborativo debe ofrecer a los desarrolladores. La metodología utilizada consistió en realizar un análisis documental sobre la propuesta de Lussier acerca de la programación colaborativa con la finalidad de determinar los aspectos de diseño, estructura e implementación de este tipo de entornos. Como resultado se obtuvo que desde el punto de vista del diseño, la comunicación entre desarrolladores, la revisión de código y la construcción del proyecto de software son los principales aspectos a considerar, y desde el punto de vista de la implementación se propone utilizar el modelo cliente - servidor y una arquitectura multiplataforma. Design Aspects of a Collaborative Programming Environment Abstract Collaborative programming or pair programming is today one of the most studied areas, because of its impact on the software developing process. The purpose of the present investigation was to determine the basic design aspects that a collaborative programming environment must offer to developers. The methodology used was a documental review of Lussier’s work about collaborative programming, to determine the design aspects, the structure and the implementation aspects of this type of environments. As result, from the design point of view, the communication between developers, code review and the construction of software project are the basic aspects to consider, and from the implementation point of view, the use of the client - server model and a multiplatform architecture are proposed.

Due to government regulations together with health and safety reasons, there are increasing demands on reducing hazardous polluting chemicals from fossil fuel power plants. Therefore, more efforts are imposed on using renewable resources such as water, wind, solar and tide to produce clean/green electricity. On top of that, there is another increasing demand from Original Equipment Manufacturers (OEMs) to operate power plants with higher load while keep the power loss to the minimum. These requirements drive conventional fluid film bearings to its mechanical and temperature limits. This calls for the development of new bearing system designs. An outstanding tribological performance such as low start-up and break-away friction, excellent resistance to chemical attack and anti-seizure properties, can be achieved by introducing compliant polymer liners. At the same time, bearings with compliant liners may alter rotor-bearing system dynamic behaviour compared to the systems with conventional white metal bearings. The research approach of this thesis is to implement compliant liner on bearing surface, impose synchronous shaft excitation and investigate the effect of bearing design parameters on bearing dynamic response. Plain cylindrical journal bearings with different compliant liner thicknesses were analysed using a FEM approach. The numerical model was compared with an in-house developed code based on the finite difference method (FDM) for a bearing operated at steady state conditions. Results obtained by the numerical models showed good agreement. After verification of the numerical model for fixed geometry journal bearings, models for tilting pad journal bearings were developed. Dynamic behaviour of the tilting pad journal bearing with three pads with line pivot geometry was compared with published data. A good agreement was obtained between the two numerical models. The effect of pad pivot geometry on bearing dynamic response was investigated. Vertical and horizontal shaft configurations were compared in terms of the effect of preload factor, radial clearance, pivot offset, and pad inclination angles. Influence of the elastic properties of compliant liners was also studied. All these factors significantly affect bearing dynamic response. It is shown how these factors should be selected to control the journal orbit sizes. Misalignments in compliant tilting pad journal bearings were analysed for load between pivots and load on pivots with consideration of thermal effects. Significant improvements in bearing performance were obtained with compliant bearings compared to white metal bearings. Furthermore, different polymer materials (PTFE, UHMWPE, pure PEEK and PEEK composite) were characterized using Frequency Response Function (FRF). It was shown that as the excitation frequency increased the equivalent stiffness was more or less constant while equivalent damping decreased exponentially. PTFE had similar equivalent stiffness compared to PEEK. As for equivalent damping, PTFE had slightly higher damping compared to PEEK or UHMWPE. Oil film thickness, oil film temperature and loads on tilting pad journal bearing were measured on 10 MW Kaplan hydroelectric power machine. Test results were compared to FEM model. It was shown that stiffness of the supporting structure may be more important to machine performance than the stiffness of the bearing alone. QC 20150409 Swedish Hydropower Centre

Material selection in architecture is not only about choosing the strongest, cheapest, or most obvious materials available. Architects also choose warm, formal, functional, or local materials for buildings. And the material options are not limited by only these considerations. The material selection process is a complex process that is influenced and determined by numerous preconditions, decisions and considerations. The current material selection tools, however, focus mainly on the technical aspects of materials. In order to make well-considered and justifiable material choices, architects have a need for information on the whole spectrum of aspects considered during the design and selection process. Earlier work presented a framework, based on a literature study and the analysis of in-depth interviews, in which the different attributes of materials that contribute to a design project were identified and organized. To refine this framework and make it available for architects during the material selection process, a group of architects was selected and assembled into a focus group. This study presents how the focus group identified, classified and commented on the considerations that are made by architects while selecting materials for a project. The evaluation of the collected data, and the discussion within the group, permitted the formulation of comments and resulted in a revised framework of material considerations, useful during the design and selection process of a material. Material properties (1), Experience (2), Manufacturing process (3), and Context (4) were identified as the different elements that are related to the material selection process. The four groups are presented here in detail. Keywords: Material Selection; Design Aspects; Architectural Experience; Material Attributes; Focus Group; Design Process

Material selection in architecture is not always based on conscious and well-considered decisions. This paper aims to get a better insight in the aspects that contribute to these decisions taken during the material selection process. A focus group study and in-depth interviews allowed to identify ‘context’, ‘manufacturing process’, ‘experience’, and ‘material aspects’ as the elements that are considered by architects when selecting materials. In this paper, the interaction between the different aspects is investigated and discussed. The context will create a set of preconditions to start from or to frame and guide decisions in the other fields. Aspects concerning the experience, manufacturing process, and the material behavior, will interact and influence each other and will be considered based on the given context. In order to make justifiable material choices, the architect will run through all four considerations before making a final material decision.

The transient pressures produced when an elevator car moves in a shaft are a potential problem for elevator smoke- control systems. This piston effect can pull smoke into a normally pressurized elevator lobby. This paper presents the results of piston effect experiments under smoke-control conditions. The results of a theoretical analysis and those of the experiments are in good agreement. For most elevators the piston-effect problem can be overcome by designs that prevent smoke from being pulled into elevator lobbies, and equations for the amount of pressurization air needed to accomplish this are presented., Reprinted from: ASHREA Transactions, v. 93, pt. 2, p. 2217-2228. ISSN: 0001-2505, Presented at the 1987 ASHRAE Annual Meeting, Nashville, TN, USA, June 27-July 1, 1987

The DUST (Delft University Settling Tube) is a settling tube system intended to analyse particle size (settling velocity) of sand ranging from 0.06 mm to 2 mm, with the sample mass varying from 0.5 g to 20 g. The main parts of the system are (see fig. 1): a. the sample introduction device (venetian blind with rotating lamellae) b. the settling tube c. the measuring device (underwater balance with feedback) All particles of a sample are released by the sample introduction device at the same time, after which they pass the settling tube. Finally they come at the balance, which measures more or less instantaneously the weight of the particles, thus yielding a cumulative settling velocity distribution. Dimensions and characteristics of the instrument and the measurement procedures have to be chosen such that the final error in the distribution function attains a minimum. Several of the relevant aspects are treated in the next sections. CONCLUSIONS a. Using an underwater balance with feedback, it is possible to measure the settling velocity distribution of (sand) particles ranging from 0.1 to 2 mm with an accuracy (systematic part of the error) better than 7%, in which 5% is due to the settling phenomenon itself (concentration effects). The precision (random part of the error) is better than 2%, including the error of sample splitting. The accuracy of the (relative) weight-measurement is better than 0.1% with a precision better than 0.5%. b. The impact of the particles can'be interpreted as a contribution to the delay time of the weighing system. As the impact partly compensates the delay time of the weighing system, the demands upon the delay time can be weakened. Given the possible velocity range, there is an optimum value of the delay time, for which the error will be smaller than 0.25 gy^2/L. c. Further research has to be done on the dependence of the settling phenomenon on the average particle diameter, the scatter in particle diameter, the diameter of the settling tube and the temperature of the sedimentation fluid.

The DUST (Delft University Settling Tube) is a settling tube system intended to analyse particle size (settling velocity) of sand ranging from 0.06 mm to 2 mm, with the sample mass varying from 0.5 g to 20 g. The main parts of the system are (see fig. 1): a. the sample introduction device (venetian blind with rotating lamellae) b. the settling tube c. the measuring device (underwater balance with feedback) All particles of a sample are released by the sample introduction device at the same time, after which they pass the settling tube. Finally they come at the balance, which measures more or less instantaneously the weight of the particles, thus yielding a cumulative settling velocity distribution. Dimensions and characteristics of the instrument and the measurement procedures have to be chosen such that the final error in the distribution function attains a minimum. Several of the relevant aspects are treated in the next sections. CONCLUSIONS a. Using an underwater balance with feedback, it is possible to measure the settling velocity distribution of (sand) particles ranging from 0.1 to 2 mm with an accuracy (systematic part of the error) better than 7%, in which 5% is due to the settling phenomenon itself (concentration effects). The precision (random part of the error) is better than 2%, including the error of sample splitting. The accuracy of the (relative) weight-measurement is better than 0.1% with a precision better than 0.5%. b. The impact of the particles can'be interpreted as a contribution to the delay time of the weighing system. As the impact partly compensates the delay time of the weighing system, the demands upon the delay time can be weakened. Given the possible velocity range, there is an optimum value of the delay time, for which the error will be smaller than 0.25 gy^2/L. c. Further research has to be done on the dependence of the settling phenomenon on the average particle diameter, the scatter in particle diameter, the diameter of the settling tube and the temperature of the sedimentation fluid.