| 1. |
- Aarno, Daniel, 1979-
(författare)
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Intention recognition in human machine collaborative systems
- 2007
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Licentiatavhandling (övrigt vetenskapligt)abstract
- Robotsystem har använts flitigt under de senaste årtiondena för att skapa automationslösningar i ett flertal områden. De flesta nuvarande automationslösningarna är begränsade av att uppgifterna de kan lösa måste vara repetitiva och förutsägbara. En av anledningarna till detta är att dagens robotsystem saknar förmåga att förstå och resonera om omvärlden. På grund av detta har forskare inom robotik och artificiell intelligens försökt att skapa intelligentare maskiner. Trots att stora framsteg har gjorts då det gäller att skapa robotar som kan fungera och interagera i en mänsklig miljö så finns det för nuvarande inget system som kommer i närheten av den mänskliga förmågan att resonera om omvärlden.För att förenkla problemet har vissa forskare föreslagit en alternativ lösning till helt självständiga robotar som verkar i mänskliga miljöer. Alternativet är att kombinera människors och maskiners förmågor. Exempelvis så kan en person verka på en avlägsen plats, som kanske inte är tillgänglig för personen i fråga på grund av olika orsaker, genom att använda fjärrstyrning. Vid fjärrstyrning skickar operatören kommandon till en robot som verkar som en förlängning av operatörens egen kropp.Segmentering och identifiering av rörelser skapade av en operatör kan användas för att tillhandahålla korrekt assistans vid fjärrstyrning eller samarbete mellan människa och maskin. Assistansen sker ofta inom ramen för virtuella fixturer där eftergivenheten hos fixturen kan justeras under exekveringen för att tillhandahålla ökad prestanda i form av ökad precision och minskad tid för att utföra uppgiften.Den här avhandlingen fokuserar på två aspekter av samarbete mellan människa och maskin. Klassificering av en operatörs rörelser till ett på förhand specificerat tillstånd under en manipuleringsuppgift och assistans under manipuleringsuppgiften baserat på virtuella fixturer. Den specifika tillämpningen som behandlas är manipuleringsuppgifter där en mänsklig operatör styr en robotmanipulator i ett fjärrstyrt eller samarbetande system.En metod för att följa förloppet av en uppgift medan den utförs genom att använda virtuella fixturer presenteras. Istället för att följa en på förhand specificerad plan så har operatören möjlighet att undvika oväntade hinder och avvika från modellen. För att möjliggöra detta estimeras kontinuerligt sannolikheten att operatören följer en viss trajektorie (deluppgift). Estimatet används sedan för att justera eftergivenheten hos den virtuella fixturen så att ett beslut om hur rörelsen ska fixeras kan tas medan uppgiften utförs.En flerlagers dold Markovmodell (eng. layered hidden Markov model) används för att modellera mänskliga färdigheter. En gestemklassificerare som klassificerar en operatörs rörelser till olika grundläggande handlingsprimitiver, eller gestemer, evalueras. Gestemklassificerarna används sedan i en flerlagers dold Markovmodell för att modellera en simulerad fjärrstyrd manipuleringsuppgift. Klassificeringsprestandan utvärderas med avseende på brus, antalet gestemer, typen på den dolda Markovmodellen och antalet tillgängliga träningssekvenser. Den flerlagers dolda Markovmodellen tillämpas sedan på data från en trajektorieföljningsuppgift i 2D och 3D med en robotmanipulator för att ge både kvalitativa och kvantitativa resultat. Resultaten tyder på att den flerlagers dolda Markovmodellen är väl lämpad för att modellera trajektorieföljningsuppgifter och att den flerlagers dolda Markovmodellen är robust med avseende på felklassificeringar i de underliggande gestemklassificerarna.
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| 2. |
- Abaravicius, Juozas
(författare)
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Load Management in Residential Buildings: Considering Techno-Economical and Environmental Aspects
- 2004
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Licentiatavhandling (övrigt vetenskapligt)abstract
- Load problems in electricity markets occur both on the supply and demand side and can have technical, economic and even political causes. Commonly, such problems have been solved by expanding production and/or distribution capacity, importing electricity or by load management. Load management is a techno-economic measure for harmonizing the relations between supply and demand sides, optimizing power generation and transmission and increasing security of supply. Interest in load management differs depending on the perspective of the actors involved: from customer, utility, or producer to state policymaker. The problem of load demand and load management in residential sector is in this thesis approached from different perspectives, i.e. technical, economic, and environmental. The study does not go deep into detailed analyses of each perspective, but rather aims to establish and analyze the links between them. This trans-disciplinary approach is the key methodological moment used in the research work performed by the research group for load management in buildings at the Lund Institute of Technology. The key objective of this study is to analyze load demand variation and load management possibilities in residential sector, particularly detached and semi-detached houses, to experimentally test and analyze the conditions and potential of direct load management from customer and utility viewpoint. Techno-economic and environmental aspects are investigated. The study was performed in collaboration with one electric utility in Southern Sweden. Ten electric-heated houses were equipped with extra meters, enabling hourly load measurements for heating, hot water and total electricity use. Household heating and hot water systems were controlled by the utility using an existing remote reading and monitoring system. The residents noticed some of the control periods, although they didn’t express any larger discomfort. The experiments proved that direct load management might be a possible solution for the utility to solve their peak demand problems. Another solution, considered by the utility and analyzed in this study is a construction of diesel peak power plant. This alternative has negative environmental consequences compared to load management. The analysis of environmental aspects was extended to national level. To include an environmental perspective is a novel approach, since traditionally, load management evaluation is limited the economic and technical viewpoints. It identifies and discusses the possible environmental benefits of load management and evaluates their significance, primary focusing on CO2 emissions reduction. The results show the importance of considering the influence of site-specific or level-specific conditions on the environmental effects of load management. On the national level, load management measures can hardly provide significant environmental benefits, since hydropower is used as the demand following production source in Sweden. Emission reductions will rather be the result of energy efficiency measures, which will cut the load demand as well as the energy demand.
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| 3. |
- Abas, Riad Abdul
(författare)
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Property measurements towards understanding process phenomena
- 2005
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Licentiatavhandling (övrigt vetenskapligt)abstract
- The main objective of this industrially important work was to gain an increasing understanding of the properties of materials such as CMSX-4 nickel base super alloy, mould powder used in continuous casting of steel and coke used in blast furnace, with special reference to the thermal diffusivities. The measurements were carried out in a wide temperature range, solid, liquid, glassy and crystalline states.For CMSX-4 alloy, the thermal conductivities were calculated from the experimental thermal diffusivities. Both the diffusivities and conductivities were found to increase with increasing temperature. Microscopic analysis showed the presence of intermetallic phases such as NiTi and NiTi2 below 1253 K. In this region, the mean free path of the phonons is likely to be limited by scattering against lattice defects. Between 1253 K and solidus temperature, these phases dissolved in the alloy adding to the impurities in the matrix, which, in turn, caused a decrease in the thermal diffusivity. This effect was confirmed by annealing the samples at 1573 K. The thermal diffusivities of the annealed samples measured at 1277, 1403 and 1531 K were found to be lower than the thermal diffusivities of non-annealed samples and the values did not show any noticeable change with time. It could be related to the attainment of equilibrium with the completion of the dissolution of γ and γ´ phases during the annealing process.Liquid CMSX-4 does not show any change of thermal diffusivity with temperature. It may be attributed to the decreasing the mean free path being shorter than characteristic distance between two neighbouring atoms.On the other hand thermal diffusivities of mould powder having glassy and crystalline states decrease with increasing temperature at lower temperature and are constant at higher temperature except for one glassy sample.Analogously, the thermal diffusivity measurements of mould powder did not show any significant change with temperature in liquid state. It is likely to be due to the silicate network being largely broken down.The thermal diffusivity is increased with increasing crystallisation degree of mould powder, which is expected from theoretical considerations.The coke sample, taken from deeper level of the blast furnace, is found to have larger thermal diffusivity. This could be correlated to the average crystallite size along the structural c-axis, Lc, which is indicative of the higher degree of graphitisation. This was also confirmed by XRD measurements of the different coke samples. The degree of graphitisation was found to increase with increasing temperature. Further, XRD measurements of coke samples taken from different levels in the shaft of the blast furnace show that the graphitisation of coke was instantaneous between room temperature and 1473 K.
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| 4. |
- Abbasi, Maisam
(författare)
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Themes and challenges in developing sustainable supply chains
- 2012
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Licentiatavhandling (övrigt vetenskapligt)abstract
- Sustainable development is one of the greatest global challenges facing human beings in the 21st century. In order to tackle sustainability related problems, several global, European, and national targets for 2050 have been set. The transition of supply chains activities towards sustainability targets calls for designing new strategies and continuously identifying and tackling the challenges that can hinder the operationalization of such strategies. The purpose of this research was to explore and classify themes and challenges in developing sustainable supply chains activities in general, and freight transport and urban distribution in particular. Three research questions were defined followed by defining the scientific assumptions and research strategies. Three research studies were then designed and carried out to find trustworthy and authentic answers to the corresponding research questions. However, research design, data collection, and data analysis were mixed and overlapping as they were not completely sequentially carried out. Data were collected by triangulation of different research methods, namely, literature review, content analysis, and semi-structured interviews. Analysis of the data was guided by principles of content analysis, discourse analysis, analytic induction, and grounded theory. Synthesis of the analyzed data resulted in the emergence of categories of themes and challenges, the development of hypotheses, and further discussion. In total, five categories of themes were identified for making supply chains environmentally sustainable, fifteen for making freight transport sustainable, and eight for making urban freight distribution sustainable. Five categories of challenges were identified for making supply chains environmentally sustainable, five for making freight transport sustainable, and seven for making urban freight distribution sustainable. All the themes and challenges were then synthesized to determine the patterns of their association. Five major themes in developing sustainable supply chains emerged, namely, increasing sustainability awareness, closing the loop of supply chains, making supply chains energy-efficient, making supply chains environmentally responsible, and managerial issues. Five major challenges in developing sustainable supply chains emerged, namely, change of behavior, costs, implementation, corporate governance, and antagonistic effects and paradoxical conflicts. As the nature of supply chains and the challenges identified in developing them sustainably is complex, a complexity theory perspective was considered beneficial for dealing with them. Such a perspective can enable us to: take a more holistic view of available sustainability-oriented strategies and activities; analyze the antagonistic effects of strategies and activities on each other; recognize conflicts of a paradoxical character that exist in supply chains; analyze the changes influencing and influenced by the strategies and activities; appreciate enough diversity and freedom among the sub-systems rather than too much simplification of them; design and redesign the transition paths for different types of supply chains. A complexity theory perspective can also be beneficial when governing a transformative transition of supply chains towards sustainability targets. Lessons are suggested in the discussion chapter that may help policy and decision makers in designing the future strategies and in tackling the challenges. The themes identified can be beneficial for increasing the absorptive capacity of industries, practitioners, and policy makers while they design innovative strategies for transitions towards sustainability targets. The identified challenges can also be beneficial for reducing the inertia and uncertainties against operationalization of sustainable development in practice.
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| 5. |
- Abbasi, Saeed
(författare)
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Characterisation of airborne particles from rail traffic
- 2011
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Licentiatavhandling (övrigt vetenskapligt)abstract
- Since the investigation of wear particles in rail transport started in late-1910s, the high mass concentration of these particles has raised worries among researchers concerned with air quality. However, effective action has yet to be taken because of lack of relevant knowledge. This thesis provides applicable information for the airborne wear particles in rail transport. Some aspects of their characteristics such as diameter size, mass concentration, number concentration, and morphology of particles were investigated in field tests and laboratory tests.The effects on particle characterisations from different operational conditions in the field tests, and applying different braking materials, conducting tests in different applied loads or sliding velocities in the laboratory tests were studied. The main advantage of conducting laboratory tests was to focus on studying particles from one source. The possibility of repetition, using high sensitive instruments and conducting tests at low costs are the other advantages of laboratory studies. Paper A describes how a pin-on-disc machine was used to reproduce similar real operational conditions during mechanical braking in a train. The results were validated by comparing the field tests results with the laboratory studies. The particles morphology and size distribution were also studied.Paper B presents a summary of field tests results. The effects of curve negotiating and applying braking in different real conditions were investigated with an on-board measurement.The element composition of the particles and their potential sources were also investigated outside of the particles morphologies.Paper C presents comprehensive results from laboratory studies on airborne particles from different braking materials. The differences in the particle characteristics in similar test conditions were attributable to different material compositions and dominant wear mechanisms. A new index was introduced in this paper and is suggested to be used as a qualitative factor with regard to the airborne wear particle emission rate.Paper D is a review of the recent studies of exhaust emission and non-exhaust emission from rail vehicles. A summary of results, measurements, adverse health effects, and proposed or applied solutions are reviewed in this paper.
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| 6. |
- Abbes, Yacine
(författare)
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Educational studies in heat and power technology
- 2005
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Licentiatavhandling (övrigt vetenskapligt)abstract
- Higher education is undergoing continuous changes and new learning tools and methods are implemented. Researchers in education do not always agree upon the effectiveness of some of the methods introduced into engineering education. The present thesis consists of two case studies on educational methods introduced at the Department of Energy Technology, at Royal Institute of Technology (KTH), Sweden. The qualitative research methodology has been used in case one and a combination of qualitative and quantitative methodology has been used in the second case. The sources of evidences consisted of: unstructured interviews, analysis of video recording, questionnaires, and analysis of a variety of documents. In the first case, an educational program in heat and power technology was analysed. The second case consists in an in-depth study of group dynamics in a Problem –Based Learning course. These studies showed that the learning approach adopted by students depends strongly on the way they view the particular learning tool or method. The first case study revealed the existence of two types of learners. Surfacelearners follow the structure suggested by the designers of the multimedia program. This category of learners focuses only on the material available in the program. Deep-learners go beyond the information and the structure suggested in the program and combine different learning tools in their learning. These students do not follow the structure of the tutorials’ of the multimedia program. This study showed that students who had a strong view how to learn with a multimedia program or a learning method benefited less from the learning tools available. Students with weak views on how to learn from educational program or leaning tool benefit less from the presentation and engage in more surface learning. Self-motivated learners use the multimedia presentation in novel ways and crosscheck the information given with other material. The second study showed that students have unclear and weak views on how to learn with student-directed Problem- Based Learning model. Four types of learners were identified in Problem-Based Learning project: Leaders, Key Actors, Common Students and Social Loafers. Leaders and Key Actors are self-motivated individuals and participate most in the projects. Students who viewed themselves or were viewed as leaders were held responsible to take most of the decisions and students expected them to work more than the average student. Students who viewed themselves as common team members expected a lower workload than leaders’. Key Actors are self-motivated students who do not view themselves as separate from other group members but who participate more than others. Leaders learned more group and social processes, that they did not fully take part in, while common students learned more from the project management aspects that they did not take part in. The study also found that Problem-Based Learning groups can become very cohesive, and can develop distorted views on how to learn with Problem-Based Learning, and un-common group dynamics phenomena such as groupthink can occur in Problem-Based Learning setting.
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| 7. |
- Abdelmassih Waller, Peter
(författare)
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Den utsträckta TV:n - Ett exempel ur praktiken
- 2007
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Licentiatavhandling (övrigt vetenskapligt)abstract
- Syftet med den här licentiatuppsatsen är dels att beskriva äldre människors intresse av och möjligheter till att använda TV:n till annat än traditionellt TV-tittande, dels att beskriva olineariteterna i den designprocess i vilken detta arbete ägde rum. Konceptet ”Den utsträckta TV:n” utvecklades och provades (av äldre människor, deras anhöriga och personal) i en ny vårdboendemiljö samtidigt som inflyttning, nyanställning och slutjustering av lokaler och teknik pågick. Totalt omfattades 30 äldre personer, med en ålder mellan 60 och 100 år, i den process som pågick mellan juni 2006 och februari 2007. En avgörande bakgrundsfaktor var att initialmotståndet mot tekniken i sig är lågt när det handlar om en så flitigt använd produkt som TV-apparaten. Detta visade sig också vara sant när - som i detta fallet - det handlade om en TV med platt skärm (gäller för alla rum och är helt oberoende av detta projektet). Funktionerna i den utsträckta TV:n var dels boendegemensamma, dels personliga. De boendegemensamma funktionerna bestod av en intern TV-kanal och två media centers med goda möjligheter att visa gemensamma internproduktioner, annat av allmänt intresse och material som anhöriga tog med sig. Den personliga funktionen handlade om kommunikation utifrån det egna fotoalbumet i den egna TV:n. Den utsträckta TV:ns funktion och användning utvecklades i och genom en väv av visioner, kompetenser, relationer, ansvarsområden och logistiska förutsättningar. Resultaten handlar både om gränssnitt och om de handlande människorna själva (de äldre, deras anhöriga, personalen, IT-konsulter, teknikleverantörer, jag själv och många fler), våra verktyg och handlingsutrymmen. Det som tagit den garanterat längsta tiden är det olineära i designprocessen. Den har varit komplex och ingalunda följt de initiala planerna. Detta är visserligen mer regel än undantag i situerade människonära designprocesser men det dokumenteras alltför sällan. Jag hoppas att lärdomarna från användningen av den utsträckta TV:n skall medverka till nytänkande kring äldre människors TV-tittande.
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| 8. |
- Abdulhadi, Nadia MN
(författare)
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Quality of interaction between primary health-care providers and patients with type 2 diabetes in Muscat, Oman
- 2007
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Licentiatavhandling (övrigt vetenskapligt)abstract
- Objectives: This study aimed at exploring the quality of interactions between health-care providers and type 2 diabetic patients at primary health-care level in Muscat, Oman, focusing on the consultation environment, care and information, and how the patients perceived these interactions. Methods: Two cross-sectional sub-studies were performed using quantitative and qualitative research methods. Data for the first sub-study was collected through direct observations of 90 consultations with 23 doctors and 85 consultations with 13 diabetes nurses in six primary health-care centres (PHCCs), using checklists developed from the National Diabetes Guidelines and other studies on patient-provider interaction. Consultations were assessed as optimal if more than 75% of observed aspects were fulfilled, sub-optimal if less than 50% were fulfilled and intermediate if the level of fulfilments was 50-75%. Data for the second sub-study was collected through focus group discussions (FGDs) among women and men with type 2 diabetes, attending the PHCCs. Qualitative content analysis was applied. Main findings: In 48% of the consultations there was an optimal environment, care and information. The score of fulfillment was lower for shorter consultations. Overall scoring of the individual doctors’ consultations showed that only ten doctors were optimal in their interactions with the patients, both creating a positive consultation environment and providing optimal care and information. The quality of the diabetes nurses’ interactions was sub-optimal in about 75% of their consultations. Some important aspects of positive interactions were poorly fulfilled by doctors and nurses such as: consultation privacy; encouraging the patients to ask questions; attention; emphasis on patients understanding of the provided information; and inquiry about adverse effects of medicine and risky habits, like smoking or alcohol consumption. There was a low referral to health educators or dieticians, and the diabetes nurses provided health education for a few patients. The combined scores of all aspects for both doctors and diabetes nurses showed that they interacted optimally with the patients in only one health centre. Participants of FGDs identified several weaknesses with regard to patient-provider communication such as: unfriendly welcoming, interruption of privacy and poor attention. Moreover, the patients expressed their inability to participate in the medical dialogue or express concerns, and they discussed other problems and difficulties related to a patient-centred approach. Furthermore, some patients perceived the doctors and nurses neither to be experts, nor as competent enough in diabetes care. In addition, the patients were dissatisfied with issues related to the organization of the diabetes clinics and access to care such as: long waiting time; lack of care continuity and poor health education. Conclusions and recommendations: The interactions of the doctors and diabetes nurses with type 2 diabetes patients were not optimal in relation to the national guidelines and there was poor collaboration between the diabetes team members. Furthermore, the patients’ were to a great extent dissatisfied with the services at PHCCs in Muscat. The role of diabetes nurses, dieticians and health educators should be enhanced. Better utility of the resources and patients’ awareness of these resources within the practice could be achieved through a multidisciplinary team approach and training of the providers to upgrade their skills regarding communication and care with emphasis on patientcentred care and empowerment approach. Barriers to compliance with the guidelines need to be further explored. The results of this study can serve as a point of departure for the policy makers in Oman and countries with similar health systems, for improving the quality of diabetes care, and for further improvement in the organizational efficiency of diabetes services.
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| 9. |
- Abdullah Asif, Farazee Mohammad, 1980-
(författare)
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Resource Conservative Manufacturing
- 2011
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Licentiatavhandling (övrigt vetenskapligt)abstract
- The question of resource scarcity and emerging pressure of environmentallegislations have put the manufacturing industry with a new challenge. On theone side, there is a huge population that demands a large quantity ofcommodities, on the other side, these demands have to be met by minimumresources and with permissible pollution that the earth’s ecosystem can handle.In this situation, technologic breakthrough that can offer alternative resourceshas become essential. Unfortunately, breakthroughs do not follow any rule ofthumb and while waiting for a miracle, the manufacturing industry has to findways to conserve resources. Within this research the anatomy of a large body ofknowledge has been performed to find the best available practices for resourceconservation. Critical review of the research revealed that none of the availablesolutions are compatible with the level of resource conservation desired by themanufacturing industry or by society. It has also been discovered that a largegap exists between the solutions perceived by the scientists and theapplicability of those solutions. Through careful evaluation of the state-of-theart,the research presented in this thesis introduced a solution of maximizingresource conservation i.e., material, energy and value added, as used inmanufacturing. The solutions emerged from the novel concept named asResource Conservative Manufacturing, which is built upon the concept ofMultiple Lifecycle of product. Unlike other research work, the researchdocumented in this thesis started with the identification of the problem andfrom which a ‘wish to do’ list was drawn. The seriousness of the problem andpotential of adopting the proposed concept has been justified with concreteinformation. A great number of arguments have been presented to show theexisting gaps in the research and from that, a set of solutions to conserveresources has been proposed. Finally, one of the prime hypotheses concerningclosed loop supply chain has been validated through the system dynamicsmodeling and simulation.
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| 10. |
- Abedan Kondori, Farid, 1983-
(författare)
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Human Motion Analysis for Creating Immersive Experiences
- 2012
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Licentiatavhandling (övrigt vetenskapligt)abstract
- From an early age, people display the ability to quickly and effortlessly interpret the orientation and movement of human body parts, thereby allowing one to infer the intentions of others who are nearby and to comprehend an important nonverbal form of communication. The ease with which one accomplishes this task belies the difficulty of a problem that has challenged computational systems for decades, human motion analysis.Technological developments over years have resulted into many systems for measuring body segment positions and angles between segments. In these systems human body is typically considered as a system of rigid links connected by joints. The motion is estimated by the use of measurements from mechanical, optical, magnetic, or inertial trackers. Among all kinds of sensors, optical sensing encompasses a large and varying collection of technologies.In a computer vision context, human motion analysis is a topic that studies methods and applications in which two or more consecutive images from an image sequences, e.g. captured by a video camera, are processed to produce information based on the apparent human body motion in the images.Many different disciplines employ motion analysis systems to capture movement and posture of human body for applications such as medical diagnostics, virtual reality, human-computer interaction etc.This thesis gives an insight into the state of the art human motion analysissystems, and provides new methods for capturing human motion.
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