Determining vehicle drivetrain dynamics using system identification

Target of this book is to propose an approach for modelling drivetrain dynamics in order to design further a vibration control system of a hybrid bus. In this thesis two approaches are examined and compared. First model is obtained by theoretical means: drivetrain is represented as a system of rotating masses, which motion is described with differential equations. Second model is obtained using system identification method: mathematical description of the dynamic behavior of a system is formed based on measured input (torque) and output (speed) data. Then two models are compared and an optimal approach is suggested.

Influence of spray drying conditions on the physical properties of dried pulp tomato

A complet factorial experimental design was applied to determinate the influence of the variable inlet air temperature, feed flow rate, and atomizer speed on the physical properties of the tomato pulp powder. Results showed that these variables had a significant positive effect on the moisture content, apparent density, and particle size and no significant effects on the porosity and true density. The best spray drying conditions to produce lower moisture content and higher apparent density tomato powder were inlet air temperature of 200 °C, feed flow rate of 276 g/min, and atomizer speed of 30000 rpm.

Weldability of high strength aluminium alloys

The need for reduced intrinsic weight of structures and vehicles in the transportation industry has made aluminium research of interest. Aluminium has properties that are favourable for structural engineering, including good strength-to-weight ratio, corrosion resistance and machinability. It can be easily recycled saving energy used in smelting as compared to steel. Its alloys can have ultimate tensile strength of up to 750 MPa, which is comparable to steel. Aluminium alloys are generally weldable, however welding of high strength alloys like the 7xxx series pose considerable challenges. This paper presents research on the weldability of high strength aluminium alloys, principally the 7xxx series. The weldability with various weld processes including MIG, TIG, and FSW, is discussed in addition to consideration of joint types, weld defects and recommendations for minimizing or preventing weld defects. Experimental research was carried out on 7025-T6 and AW-7020 alloys. Samples were welded, and weld cross sections utilized in weld metallurgy studies. Mechanical tests were carried out including hardness tests and tensile tests. In addition, testing was done for the presence of Al2O3 on exposed aluminium alloy. It was observed that at constant weld heat input using a pulsed MIG system, the welding speed had little or no effect on the weld hardness. However, the grain size increased as the filler wire feed rate, welding current and welding speed increased. High heat input resulted in lower hardness of the weld profile. Weld preheating was detrimental to AW- 7020 welds; however, artificial aging was beneficial. Acceptable welds were attained with pulsed MIG without the removal of the Al2O3 layer prior to welding. The Al2O3 oxide layer was found to have different compositions in different aluminium alloys. These findings contribute useful additional information to the knowledge base of aluminium welding. The application of the findings of this study in welding will help reduce weld cost and improve high strength aluminium structure productivity by removing the need for pre-weld cleaning. Better understanding of aluminium weld metallurgy equips weld engineers with information for better aluminium weld design.

Methods of overcoming dormancy in Schizolobium amazonicum Huber ex Ducke (Leguminosae - Caesalpinioideae) seeds

Seed dormancy is a frequent phenomenon in tropical species, causing slow and non-uniform germination. To overcome this, treatments such as scarification on abrasive surface and hot water are efficient. The objective of this study was to quantify seed germination with no treatment (Experiment 1) and identify an efficient method of breaking dormancy in Schizolobium amazonicum Huber ex Ducke seeds (Experiment 2). The effects of manual scarification on electric emery, water at 80ºC and 100ºC and manual scarification on wood sandpaper were studied. Seeds were sown either immediately after scarification or after immersion in water for 24h in a sand and sawdust mixture. Germination and hard seed percentages and germination speed were recorded and analyzed in a completely randomized design. Analysis of germination was carried out at six, nine, 12, 15, 18, 21 and 24 days after sowing as a 4x2 factorial design and through regression analysis. Treatment means of the remaining variables were compared by the Tukey test. Seed germination with no treatment started on the 7th day after sowing and reached 90% on the 2310th day (Experiment 1). Significant interaction between treatments to overcome dormancy and time of immersion in water was observed (Experiment 2). In general, immersion in water increased the germination in most evaluations. The regression analyses were significant for all treatments with exception of the control treatment and immersion in water at 80ºC. Germination speed was higher when seeds were scarified on an abrasive surface (emery and sandpaper) and, in these treatments, the germination ranged from 87% to 96%, with no hard seeds. S. amazonicum seeds coats are impermeable to water, which hinders quick and uniform germination. Scarification on electric emery followed by immediate sowing, scarification on sandpaper followed by immediate sowing and sowing after 24h were the most efficient treatments for overcoming dormancy in S. amazonicum seeds.

Jauhatusparametrien vaikutus jauhatustuotteen partikkelikokoon ja suodattuvuuteen

Tämän diplomityön tarkoituksena on tutkia ensin jauhatusparametrien vaikutus rikastushiekan hienousasteeseen eli miten partikkelikokojakaumaa kuvaavat partikkelikoot muuttuvat. Tämän jälkeen tutkitaan miten rikastushiekan hienousasteen muuttuminen vaikuttaa jauhettujen rikastushiekkalietenäytteiden suodattuvuuteen. Partikkelikokojakauman variaatioista yritetään löytää yhteys suodinkakun ominaisvastuksen ja huokoisuuden välillä. Jauhatus suoritettiin laboratoriomittakaavan helmimyllyllä märkäjauhatuksena. Jauhatusta varten tehtiin kolmitasoinen faktorikoesuunnitelma, jossa muuttujina ovat lasihelmien halkaisija, jauhatusaika ja sekoitinelimen pyörimisnopeus. Suodatus toteutettiin vakiopainesuodatuksena kolmella eri suodatuspaineella Nutsche-suodattimella. Työn tuloksista saatiin selville, että partikkelikokojakauman leveys korreloi suodinkakun ominaisvastuksen kanssa. Kun partikkelikokojakauma leveys muuttui kapeammaksi, saatiin kakun ominaisvastus pienemmäksi ja suodatukseen kulunut aika lyheni. Kapein partikkelikokojakauman leveys saatiin suurimmalla helmen halkaisijalla, pisimmällä jauhatusajalla sekä suurimmalla sekoitusnopeudella.

Letting go : a self-study utilizing critical literacy as method in improving my practice /

This is a Self-study about my role as a teacher, driven by the question: "How do I improve my practice?" (Whitehead, 1989)? In this study, I explored the discomfort that I had with the way that I had been teaching. Specifically, I worked to uncover the reasons behind my obsessive (mis)management of my students. I wrote of how I came to give my Self permission for this critique: how I came to know that all knowledge is a construction, and that my practice, too, is a construction. I grounded this journey within my experiences. I constructed these experiences in narrative fomi in order to reach a greater understanding of how I came to be the teacher I initially was. I explored metaphors that impacted my practice, re-constructed them, and saw more clearly the assumptions and influences that have guided my teaching. I centred my inquiry into my teaching within an Action Reflection methodology, bon-owing Jack Whitehead's (1989) term to describe my version of Action Research. I relied upon the embedded cyclical pattern of Action Reflection to understand my teaching Self: beginning from a critical moment, reflecting upon it, and then taking appropriate action, and continuing in this way, working to improve my practice. To understand these critical moments, I developed a personal definition of critical literacy. I then tumed this definition inward. In treating my practice as a textual production, I applied critical literacy as a framework in coming to know and understand the construction that is my teaching. I grounded my thesis journey within my Self, positioning my study within my experiences of being a grade 1 teacher struggling to teach critical literacy. I then repositioned my journey to that of a grade 1 teacher struggling to use critical literacy to improve my practice. This journey, then, is about the transition from critical literacyit as-subject to critical literacy-as-instmctional-method in improving my practice. I joumeyed inwards, using a critical moment to build new understandings, leading me to the next critical moment, and continued in this cyclical way. I worked in this meandering yet deliberate way to reach a new place in my teaching: one that is more inclusive of all the voices in my room. I concluded my journey with a beginning: a beginning of re-visioning my practice. In telling the stories of my journey, of my teaching, of my experiences, I changed into the teacher that I am more comfortable with. I've come to the frightening conclusion that I am the decisive element in the classroom. It's my personal approach that creates the climate. It's my daily mood that makes the weather As a teacher, I possess a tremendous power to make a person's life miserable or joyous. I can be a tool of torture or an instrument of inspiration. I can humiliate or humour, hurt or heal. In all situations, it is my response that decides whether a crisis will be escalated or de-escalated and a person humanized or de-humanized. (Ginott, as cited in Buscaglia, 2002, p. 22)

Letter - E.C. Schmon to Arthur A. Schmon, 31 May 1918

The letter reads: " Darling Artie, I have just been reading the war news and Oh! how terribly discouraging it is. This mornings paper says the allies have yieldes on a forty-mile front, that Soissons had been taken by the Germans and Rheims is in grave peril and may fall at any moment. And think - only the third day of the new drive, too. I know that everything will end all right, but it surely has an awful affect on you, to read these reports. Of course no one knows, but it is the opinion of people in military circles here, that the war will last two years more at least; and in all probability five or six. Cheerful prospects. Yes? So you see, Artie dear, that you must come home on a leave, the very first opportunity you have. Understand? I am going down to Red Cross now, to do a little work. Tonight Mrs. Mizger, Doris and the two Braun girls are coming down. They want to see the rest of the pretty things that are in our sacred chest, and I just love to them, too. There are days when I have them out three or four times and I picture each thing in our little nest - after the war is over - - (Joy!!) Au revoir, honey-bunch boy. All the love, hugs and kisses that you desire. Always your, Wifie. P.S. And still no mail. Boo! Hoo! L."

HG 249.40-249.55 Thin Section

Coarse grained sample with clasts ranging from small to medium. Clast shape ranges from angular to sub-angular. Lineations and rotation structures seen. Clay material and fine grained domains (darker colour) also seen.

HG 276.80-276.95 Thin Section

Coarse grained sample, with grains ranging from small to large in size. Shapes range from angular to rounded. This sample is abundant in lineations, and rotation structures can also be seen around larger aggregates. Many large grains are fractured and minor grain stacking can also be seen.

HG 362.70-362.80

Multiple domains are present. Clasts range from small to large in size and sub-angular to sub-rounded in shape. The fine grained domain is dark brown with some lineations and organic material. The coarse grained domain is grey in colour and contains mainly lineations and rotation structures. Some comet structures can also be seen.

HG 421.50-421.60

Light brown sediment with clasts that range from small to large in size. The clast shape ranges from sub-angular to sub-rounded. Lineations and rotation structures are abundant in this sample. Edge-to-edge grain crushing is present as well. There are areas of light and dark sediment throughout the sample. A few comet structures can also be seen.

HG 456.70-456.80

Dark brown sediment with clasts ranging from small to large in size. Clast shape ranges from angular to sub-rounded. Lineations are common throughout the sample. A few comet structures and rotation structures are also visible throughout the sample.

HG 484.65-484.80

Brown sediment with multiple domains. Grains range from small to large in size, and angular to sub-rounded in shape. Large amounts of grain crushing can be seen in the coarser domains. The sample is mainly dominated with grain crushing. The finer grained domains contain some clay rich material. Some lineations and rotation structures can also be seen throughout the different domains.

HG 498.20-498.35

Coarse grained sample with clasts ranging from small to medium in size. Clast shape ranges from angular to sub-rounded. Lineations and rotation structures are common in this sample. Grain crushing and comet structures are also present in minor amounts.

HG 3.75-3.85

Dark brown sediment with clasts ranging from small to large. The clasts range from angular to sub-rounded in shape. The sample mainly contains edge-to-edge grain crushing and rotation structures. Many grains are fractured and a few necking structures can also be seen.