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83 Uppsatser om Particle - Sida 5 av 6

Kollision deformation med fokus på solida objekt

En realistisk simulation kräver att alla simulerade objekten ska interaktivt och dynamiskt animeras. Delar av objektens kropp ska deformeras och andra delar ska sönderfalla vid en krock med ett annat objekt. De flesta 3d applikationer har som gemensamt vissa tekniker som används vid dynamiska simulationer. Tyvärr så finns det inte en smidig och snabb teknik för att deformera solida objekt vid kollisioner, detta gäller även Maya som jag använde i detta arbete. Detta arbete ska visa en smidig teknik att deformera vissa delar av en komplicerad modell och få andra delar att splittras och spridas i en dynamisk simulation som är både fysiskt rätt och ser visuellt bra ut.

Uppfyller BIM förväntningarna som arbetsmetod för broprojekt?

The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier Particles. Those Particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.

Skogen i barnlitteraturen : Kan den fungera som en källa till naturvetenskaplig kunskap?

The amount of various phosphorus (P) fractions in the sediment and the relationship between the amount of P and sediment Particle size were investigated in a constructed wetland southwest of Linköping. Furthermore, the possible correlation between clay content in the sediment and distance from the inlet was investigated. Sediment samples were collected along three transects from the inlet to the outlet, with six samples in each transect. In order to measure the soluble P, an NH4Cl extraction was done. This was also analysed for total soluble P after oxidation with peroxodisulphate.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Utvärdering av den gröna smileyn inom livsmedelsinspektion : En intervju och enkätstudie i Halmstads kommun

With a growing population on earth the amount of end-of-life vehicles (ELVs) and other scrap steel increases. The European Directive 2000/53/CE? requires a minimum of 95 % reuse and recovery and 85 % re-use and recycling no later than 1 January 2015, for end-of life vehicles. This imposes a need for more efficient recycling and recovery. Despite this shredder residue (SR) is commonly land filled.This report investigated the magnetic fines residue generated at Stena Metall shredder facility in Halmstad, Sweden.

Karaktärisering, utvärdering och avsättning av Stena Metalls magnetiska fines

With a growing population on earth the amount of end-of-life vehicles (ELVs) and other scrap steel increases. The European Directive 2000/53/CE? requires a minimum of 95 % reuse and recovery and 85 % re-use and recycling no later than 1 January 2015, for end-of life vehicles. This imposes a need for more efficient recycling and recovery. Despite this shredder residue (SR) is commonly land filled.This report investigated the magnetic fines residue generated at Stena Metall shredder facility in Halmstad, Sweden.

Tillverkning av mikronålar för medicinsk tillämpning

Transdermal drug delivery, besides painfulinjections with syringes, has long been associatedwith small size Particle pharmaceuticals, which candiffuse through the skin. This method of drugadministration has only been applicable on a smallnumber of drugs, where active molecules are smalland delivery time should or can be long.Other drug delivery options are oral administrationand injection with hypodermic needles (ordinaryhospital syringes). In oral administration thestomach and liver tend to dissolve the drug and theeffect becomes more difficult to anticipate, anddrug delivery rates difficult to control. Hypodermicneedles are used as a mean of drug injectiondirectly into the bloodstream. This method ispainful and risks infection due to tissue damageand skin penetration.One way to get a painless non-damaging techniquewith high delivery rate that still can delivery largemolecules is to manufacture an array of microscopichollow needles and equip them with a pumping unitthat delivers the correct amount of drugs.This thesis shows the technique and possibility ofmanufacture micromachined needles using low costtechniques of Ion Track Technology (radiation ofheavy ions creates porous materials), electrolessdeposition (non-current activated wet chemistrymethod of depositing metal) and electroplating.

Integrerad arbetsprocess mellan projektör och konstruktör, För effektiv och kvalitetssäker projektering med Tekla Structures och SAP2000

The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier Particles. Those Particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.

Biomass losses during short-term storage of bark and recovered wood

Storage of biomass is associated with problems like heat development, biomasslosses, and reduction of the fuel quality. Certain processes such as biological- andchemical degradation are responsible for these storage problems. This master?sthesis was carried out at Vattenfall Research and Development AB and is alignedtowards quantifying the biomass losses from short-term storage (1-2 months) ofbark and recovered wood. The biomass was stored in outdoor piles during differentseasons, campaign 1 (summer) and campaign 2 (autumn).

MCNP-modell för beräkning av neutrondos och DPA på reaktortanken vid Ringhals 2

In this report an MCNP (Monte Carlo N-Particle) model is described for the reactor vessel at Ringhals 2. The model is validated against the specific activity in neutron dosimeters, extracted in 1977, 1984 and 1994. The validation showed that the calculations of the model are within the requirements of a maximum of 20 percent uncertainty for every neutron dosimeter except one, extracted after the first cycle. The uncertainty of this cycle was mostly due to the operation data rather than to the MCNP model.The model has been used to investigate various questions concerning radiation damage. The reliability of the traditional measure of radiation damage, fast neutron flux (En > 1MeV) has been evaluated.  This has been done by taking the ratio for this and another measure of radiation damage, DPA (Displacement Per Atom), for various positions and layers.

Mätning av Emissioner från en Diesel Motor under Transient Driftförhållande

Transient driftförhållande blir allt mer intressant för forskare och tillverkare och de största svårigheterna är att minska emissionerna utan att påverka bränsleförbrukningen eller motorns respons vid gaspådrag negativt. Huvudmålet med det här examensarbetet var utvärdera olika metoder för att mäta NOx och antal partiklar med hög tidsupplösning för att möjliggöra studier av emissioner under transient driftförhållande.I arbetet har en Horiba MEXA 120NOx NOx-sensor studerats med avseende på linearitet, mätsäkerhet och responstid. Försök för att öka noggrannheten har också gjorts genom att kompensera för varierande skalfaktor för utsignalen och för responstiden.Ett spädsytem har arbetats fram för att ge hög tidsupplösning och god repeterbarhet. I detta ingick en Rotating Disc spädare och en två-stegs Dekati spädare. Spädsystemet var kopplat till en TSI Ultrafine Condensation Particle Counter 3025 A (CPC) och var nödvändigt för att hålla koncentrationen inom det mätbara området.

Kvantfysiken och den nya myten? : En studie av Fritjof Capras och Danah Zohars böcker om kvantandlighet

This study is about quantum physics and the role it can play in a religious perspective. I intend to examine how moderna physics may be related and understood as New age and Myths. My material consists of two books in the new age genre: "The Tao of Physics" by Fritjof Capra and "The Quantum Self" by Danah Zohar. My first two question to these books are which 1) religious and 2) scientific content they have. My other questions are too 3) investigate and demonstrate how these books are new age and 4) to exanine how the books can function as myths and adopt mythical features.

Hur uppnår vi god inomhusmiljö i förskolan idag?

Abstract:This thesis work has been conducted at the Real Estate Department in Halmstad.The department consists of a construction/project management-unit and an operation/management-unit.Like many other towns in Sweden, Halmstad has had a long lasting problem with indoor environment. Not at least at their preschools.Today they are constructing from current building regulations. They have learned from negative experiences which have occurred in the indoor environment in older buildings.Focus is now on healthy materials, like low emission value, energy efficiency and optimization of the building, but still with soft parameters such as cleaning, interior and choice of materials.The fixtures is provides by the real estate department and the furnishings are provides by the children and youth administration. Together they are trying to provide a great indoor environment.I have, together with the real estate department and the children and youth administration of Halmstad, investigated how to provide a good indoor environment in the preschools with small funds.In my thesis there is one theoretical part with a questionnaire survey of how the preschool staff is experiencing their indoor environment to determine where the problems often start. And a practical part with measurements to try and come down to a result that analysis the cause of the problems and also to make sure that the ventilation systems are fulfilling projected values.The measurements and the questionnaire surveys was made at Lokes preschool in Frösakull, Askens preschool in Oskarström and Gullbrandstorps preschool.There were some differences between the staff-responses at the three different preschools.At Askens preschool they feel that the premises are cleaned poorly.At Gullbrandstorps preschool they feel that the indoor-air is bad because they can´t open the windows.

Analys av turbulensmodeller för CFD

This thesis has been a part of Forsmarks Kraftgrupp AB's evaluation of a turbulencemodel used in simulation of turbulent flow called PRNS (Partially Resolved NumericalSimulation). This model has promising properties and may be of use in savingcomputational resources. The purpose of this thesis was to analyze this model andcompare it with industrially applied models such as k-omega SST and LES (Large EddySimulations).PRNS works as a hybrid of the k-omega SST and DNS (Direct Numerical Simulation)where a constant, RCP (Resolution Control Parameter) with a value between 0 and 1are selected. This constant is then used in the calculations and determines thebehavior of the simulation. When RCP is set to zero the equation are the same as fora DNS simulation and when RCP is set to one the equations for k-omega SST issolved.

Utveckling av en LC-MS-metod för analys av gamma-hydroxibutyrat, gamma-butyrolakton, 1,4-butandiol, amfetamin och metadon

In this project a LC-MS-method for the analysis of gamma-hydroxybutyrate, gamma-butyrolactone, 1,4-butanediol, amphetamine and methadone was developed.Initially, the efficiency of the ionisation of the analytes was evaluated with respect to the ionisation technique (ESI, APCI and APPI) and the composition of the mobile phase. In the next step a number of different columns was tested in order to find the one with the greatest potential for separation of the substances in question. Using the selected column, the separation was optimised by means of experimental design and the software The Unscrambler 7.8. The parameters studied were the flow rate, the column temperature and the mobile phase composition. The response variables were the resolution between the target compounds and the retention time of the last eluting compound.These experiments showed that, in order to obtain the best ionisation, the mobile phase should consist of 5 mM formic acid in water and acetonitrile.

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