Monolithic integration of optoelectronics on silicon is adream. This thesis deals with the studies on the heteroepitaxyof indium phosphide on silicon substrate towards making thatdream come true. Materials growth issues, characterization anddefect identification are addressed. Epitaxial lateral overgrowth (ELOG) technique is used togrow high quality epitaxial indium phosphide on a siliconsubstrate provided with a low quality indium phosphide seedlayer. Hydride vapor phase epitaxy is used for ELOG. The growthparameters were optimized first by carrying out ELOGexperiments on an InP substrate. The lateral growth rate isstrongly dependent on the orientation of the openings,thehighest growth rate being for the openings oriented at 30ºand 60º off [110]directions. But the vertical growth rateis relatively unaffected by the opening orientation. Theobservation of an inhomogeneous and orientation dependentdopant distribution within the same layer has been explained byinvoking the bonding configurations exposed to theincorporating dopant atoms in the different emergingplanes. When ELOG of InP is conducted on InP/Si, unlike that on InPsubstrates, the lateral growth is not symmetric on both sidesdue to the propagation of defects from the seed layer. Forexample, a higher concentration of threading dislocationsintersecting the surface of the {111}A emerging planes wouldcause a higher growth rate of these planes. The growth rate of{111}A planes with respect to the others can also be caused bythe vapor phase supersaturation as predicated byBurton-Cabrera-Frank model. The determined dislocation densityin the ELOG InP on InP/Si is ~ 4X107cm-2, which is nearly two magnitude lower than in theseed layer (~ 4X109cm-2). If the seed layer is of a better quality, theELOG layer will also be. Combination of high resolution x-raydiffraction reciprocal lattice mapping and low temperaturephotoluminescence indicates that the ELOG InP layer with highaspect ratio is nearly strain-free. When ELOG of sulfur doped InP is conducted on ring shapedopenings on InP/Si substrate instead of stripe openings,octahedral shaped ELOG InP templates with smooth surface areformed. Strain compensated InGaAsP 6 periods multi-quantumwells (MQW) at 1.5 μm wavelength (target value) were grownon these templates by metalorganic vapor phase epitaxy. RT-PLis indicative of a good quality ELOG layers. Optimized ELOG onring openings may become very attractive for heteroepitaxy ofIII-V compounds on silicon. As an extension of ELOG of InP on InP/Si, growth of InP isalso conducted on planar Focused-Ion-Beam (FIB)-modified (001)GaAs substrate. The impacts of the III/V ratio,crystallographic orientation of implanted lines andimplantation dose were explored. The choice of suitable growthconditions makes it possible to obtain continuous InP wiresaligned in all possible directions.

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Cargotec Sweden AB i Hudiksvall konstruerar och producerar lyftkranar för skogsindustrin samt styckegodshantering och specialbyggda kranar för olika ändamål. Konstruktionsavdelningen jobbar kontinuerligt med att vidareutveckla befintliga kranmodeller. Produktionsanläggningen är den största för lastbilskranar inom koncernen.   Kranarna tillverkas till största del i stål av olika hållfasthet. Syftet med detta arbete har varit att undersöka vilka av de icke lyftande delarna hos Cargotecs styckegodskranar HIAB av modellerna 211 till 288 som kan tjäna mest på att konstrueras i ett alternativt material. Då andra material används måste alternativa tillverkningsmetoder och omkonstruering vara en del av arbetet, detta för att vara säker på att produkten går att förverkliga.    För att ta reda på vilka detaljer som var lämpliga att vidareutveckla utfördes en förundersökning där olika detaljer som kunde vara lämpliga att konstruera i annat material utvärderades.   Utifrån förundersökningen framkom två detaljer, ramen till elektronik- och hydraulikstyrning samt bussningar till utskjutskolvarna. Dessa två hade ett högt pris och möjligheter att omkonstruera i annat material. En undersökning av ramen och bussningarna utfördes.   Olika lastfall som förekom studerades och den begränsade ytan där bussningarna monteras medförde svårigheter vid val av material. Den nya utformningen av bussningarna använder nästan hela den tillgängliga ytan för att minska påfrestningarna. På grund av de höga spänningarna valdes en liknande sorts tennbrons men tillverkningsmetoden byttes från svarvning och fräsning till sintring. Priset för bussningarna kunde då mer än halveras, från 24 kr till 10 kr.   Ramen i plast konstruerades om för att ha samma styrka som den i stål. Att byta material för ramen medförde minskad vikt och pris, vikten reducerades från 4,55 kg till 1,5 kg och priset från 538 kr till cirka 300 kr. Även ergonomin kunde förbättras genom att göra bågen, där kranoperatören vilar sina armar, bredare. / Cargotec Sweden AB in Hudiksvall designs and manufactures cranes for the timber industry, general cargo handling and custom built cranes for various purposes. The construction division is continuously working to further develop the existing crane models. Cargotec in Hudiksvall has the lagest production plant for building truck cranes in the group.   The cranes are made mostly of steel of various strength. The purpose of this work was to investigate which of the non lifting parts of Cargotec's Hiab cranes in the model range 211-288, which can benefit most from beeing constructed in an alternative material. When other materials are used, alternative manufacturing methods and redesigning must be a part of the work, this in order to be sure that the product actually can be implemented.   To find the details that were suitable for further development an investigation was carried out in which various details that could be suitable to construct in other materials was evaluated.   The preliminary investigation revealed two parts, the framework for electronic and hydraulic control and bushings for the hydraulic pistons. These two had a high price and an opportunity to be redesigned in other material. An examination of the frame and the bushings were performed.   Different load cases were studied and the limited area where the bushings mounted made it difficult to select materials. With the new configuration of the bushes, nearly all the available surface area where used to reduce stress. Because of high stress a similar kind of tin bronze where used, but the manufacturing method was changed from turning and milling to sintering. The price of the bushings was then more than halved, from 24 kr to 10 kr.   The frame of plastic was constructed to have the same strength as that of steel. Changing the material of the frame led to decreased weight and price, the weight was reduced from 4.55 kg to 1.5 kg and the price from 538 kr to about 300 kr. Also the ergonomics could be improved by making the lower part, where the crane operator rests his arms, wider.

Syftet med vår uppsats är att studera hur barnen i förskolan använder de fysiska rummen och dess material, exempelvis leksaker och böcker. Vi vill även använda oss av ett genusperspektiv för att analysera miljön och dess material i interaktion med barn och pedagoger. Vi vill även studera om pedagogerna ger barnen möjligheter eller skapar begränsningar för flickor och pojkar. Blir förskolans material tillgängligt eller otillgängligt beroende på barnens kön? Vilka normer producerar de barnböcker som finns på avdelningarna? Vilket inflytande har barnen över miljön? Dessa är några av de frågor vi sökt svar på med hjälp av en kvalitativ, hermeneutisk ansats. Vår empiri grundar sig på observartioner och pedagogintervjuer från två olika avdelningar på två förskolor. Den ena avdelningen har en genusmedveten profil och den andra avdelningen har ingen tydlig pedagogisk profil. Dock har den sistnämnda avdelningen en utbildad genuspedagog i verksamheten. Våra teoretiska utgångspunkter grundar sig i det postmoderna perspektivet, samt det feministiska poststrukturalistiska perspektivet. Studien bygger på tidigare forskning inom inomhusmiljö och genus, samt en kortare historisk genomgång över dessa för att skapa en större överblick och en fördjupad förståelse för ämnets relevans inom den svenska förskoleverksamheten. I våra slutsatser kom vi fram till att inomhusmiljön i sig inte är marginaliserande ur ett genusperspektiv. Dock skapas istället begränsningar för både flickor och pojkar, i form av bland annat otillgängligt material. Vi hoppas att denna studie kommer öka läsarens medvetenhet genom att belysa kopplingen mellan inomhusmiljön, genus, pedagogernas förhållningssätt, barnens inflytande, samt de normer som produceras inom verksamheten. Anledningen varför vi valt att skriva om miljön och genus i förskolan är för att vi anser att miljön och genus är viktiga och intressanta då vi menar att dessa skapar möjligheter och begränsningar för barnen beroende på vilket förhållningssätt pedagogerna väljer att anamma i verksamheten.

The principal aim of this essay was to study why some teachers at upper secondary school choose to work with alternative material in the English classroom, whereas others choose a combination of alternative material and coursebooks. The investigation further deals with how alternative material is used. What students think about various kinds of material and whether they are encouraged to influence the choice of material has been considered as well. The method used was interviews with three teachers and six students. The results of the study showed that all three teachers agreed that coursebooks should not be the only teaching material used in the classroom; they believed that the use of course-books alone would be boring and not very stimulating for the students. Coursebooks combined with alternative material were considered to work very well as teachers and students benefit from the advantages of both. Furthermore, alternative material would be used more if it were not such a time-consuming business for the teachers. Concerning how the three teachers made alternative material, practise varied. One teacher for who mainly used alternative material and also made it herself, had many different sources, whereas the other two teachers mostly used books and movies. Regarding the students, their requests of teaching material varied. The majority however preferred either alternative material or a combination with coursebooks. They also declared that they are encouraged to influence the choice of material.

Solid state lighting industry is booming in recent years because of the green energy requirement. Therefore, phosphorescent OLEDs using phosphorescent emitters doped into charge-transporting hosts as emissive layers (EMLs) have attracted extensive interest due to their highly efficient emission compared to conventional fluorescent OLEDs, through radiative harvesting of both electro-generated singlet and triplet excitons. To achieve better charge balance and device performance, many researchers focus on developing new phosphorescent host materials with bipolar charge transporting property. In this work, we successfully designed and synthesized a host material CzppT containing hole-transporting carbazole and electron-transporting pyridine and investigated the physical properties. With a high triplet energy, CzppT is considered a promising universal host material and has been applied to phosphorescent OLEDs of blue/white colors. Blue/white OLEDs based on CzppT as host and Firpic/Ir(piq)2(acac) as dopant materials show maximum external quantum efficiencies (11.0% for blue, 11.32% for white) and CIE coordinates [(0.18,0.41)for blue, (0.32,0.36) for white)]. The results indicate that the bipolar host CzppT with high triplet energy has potential in manufacturing blue and white OLEDs for display or lighting applications.

The highly nonlinear nature of unsaturated flow results in different ways to approximate the delayed or instantaneous movement of the water table. In nearly all the approaches, the water table is conceptually treated as a “material surface”. This term defines the water table as having two simultaneous properties: 1) the pressure along the surface is atmospheric pressure, and 2) the water table is fixed to the material, i.e., a set of water particles. This article makes an attempt to explain that the water table, defined as the surface at atmospheric pressure, is not a material boundary, and the water table can move independent of the water particles. Velocity of the water table and velocity of drainage are compared with three analytical models: the Neuman model, which assumes instantaneous drainage from the unsaturated zone; the Moench model, which considered gradual drainage from the unsaturated zone using a series of exponential terms in the water table boundary condition; and the Mathias-Butler model, which obtained a new drainage function based on a linearized Richard’s equation but limited the variation of soil moisture and hydraulic conductivity in the unsaturated zone to exponential functions. Numerical analysis was conducted with VS2DT and both the numerical and the analytical results were compared with a 7-day, constant rate pumping test conducted by University of Waterloo researchers at Canadian Air Force Base Borden in Ontario, Canada.

In this thesis, we described our efforts to achieve antenna radomes that enhance antenna gain by using the artificial synthesis structure of the left-handed material. The characteristics of the metamaterial are introduced. Also, we will analyze the phenomena of the left-handed material which distinguish them from the right-handed material. Moreover, we analyze and derive the theory to obtain the effect of the meta-materials with the metal line artificial synthesis array structure. Then, we will focus on the method of lowering the frequency of the left-handed material structure and discuss the frequency influence of the permeability, permittivity, and refractive index as the modulus of the refractive index is smaller than one or negative. We will adjust the structure to allow a wider useful frequency bandwidth. In order to prevent from the reflection of the metal lines to cause too much loss, we will simplify the structure of the single unit. Making use of the above-mentioned methods, we use the material to achieve an antenna radome. The meta-material radome can reduce the 3 dB beam-width by about 30 percent compared with the conformal patch at 5.25 GHz. Finally, we design a novel structure of unit cell based on the CSRR which is provided with a broadband negative index of refraction. The relative bandwidth of the LHM proposed in this thesis is 36.5%. In order to reduce loss tangent we remove the dielectric substrate, which further reduce the 3 dB beam-width.

<p>Monolithic integration of optoelectronics on silicon is adream. This thesis deals with the studies on the heteroepitaxyof indium phosphide on silicon substrate towards making thatdream come true. Materials growth issues, characterization anddefect identification are addressed.</p><p>Epitaxial lateral overgrowth (ELOG) technique is used togrow high quality epitaxial indium phosphide on a siliconsubstrate provided with a low quality indium phosphide seedlayer. Hydride vapor phase epitaxy is used for ELOG. The growthparameters were optimized first by carrying out ELOGexperiments on an InP substrate. The lateral growth rate isstrongly dependent on the orientation of the openings,thehighest growth rate being for the openings oriented at 30ºand 60º off [110]directions. But the vertical growth rateis relatively unaffected by the opening orientation. Theobservation of an inhomogeneous and orientation dependentdopant distribution within the same layer has been explained byinvoking the bonding configurations exposed to theincorporating dopant atoms in the different emergingplanes.</p><p>When ELOG of InP is conducted on InP/Si, unlike that on InPsubstrates, the lateral growth is not symmetric on both sidesdue to the propagation of defects from the seed layer. Forexample, a higher concentration of threading dislocationsintersecting the surface of the {111}A emerging planes wouldcause a higher growth rate of these planes. The growth rate of{111}A planes with respect to the others can also be caused bythe vapor phase supersaturation as predicated byBurton-Cabrera-Frank model. The determined dislocation densityin the ELOG InP on InP/Si is ~ 4X10⁷cm^-2, which is nearly two magnitude lower than in theseed layer (~ 4X10⁹cm^-2). If the seed layer is of a better quality, theELOG layer will also be. Combination of high resolution x-raydiffraction reciprocal lattice mapping and low temperaturephotoluminescence indicates that the ELOG InP layer with highaspect ratio is nearly strain-free.</p><p>When ELOG of sulfur doped InP is conducted on ring shapedopenings on InP/Si substrate instead of stripe openings,octahedral shaped ELOG InP templates with smooth surface areformed. Strain compensated InGaAsP 6 periods multi-quantumwells (MQW) at 1.5 μm wavelength (target value) were grownon these templates by metalorganic vapor phase epitaxy. RT-PLis indicative of a good quality ELOG layers. Optimized ELOG onring openings may become very attractive for heteroepitaxy ofIII-V compounds on silicon.</p><p>As an extension of ELOG of InP on InP/Si, growth of InP isalso conducted on planar Focused-Ion-Beam (FIB)-modified (001)GaAs substrate. The impacts of the III/V ratio,crystallographic orientation of implanted lines andimplantation dose were explored. The choice of suitable growthconditions makes it possible to obtain continuous InP wiresaligned in all possible directions.</p>

<p>The principal aim of this essay was to study why some teachers at upper secondary school choose to work with alternative material in the English classroom, whereas others choose a combination of alternative material and coursebooks. The investigation further deals with how alternative material is used. What students think about various kinds of material and whether they are encouraged to influence the choice of material has been considered as well. The method used was interviews with three teachers and six students.</p><p>The results of the study showed that all three teachers agreed that coursebooks should not be the only teaching material used in the classroom; they believed that the use of course-books alone would be boring and not very stimulating for the students. Coursebooks combined with alternative material were considered to work very well as teachers and students benefit from the advantages of both. Furthermore, alternative material would be used more if it were not such a time-consuming business for the teachers. Concerning how the three teachers made alternative material, practise varied. One teacher for who mainly used alternative material and also made it herself, had many different sources, whereas the other two teachers mostly used books and movies. Regarding the students, their requests of teaching material varied. The majority however preferred either alternative material or a combination with coursebooks. They also declared that they are encouraged to influence the choice of material.</p>