Mekatronisen portaattomasti säädettävän ajoneuvotehonsiirtokoneiston suunnittelu ja simulointi

Työn tarkoituksena on tutkia tehonsiirron ratkaisuja, jotka mahdollistavat jatkuvanopeus ja -momentinsäädön. Työ on rajattu käsittämään kahta eri planeettavaihdetuotetta. Tutkimuksen kohteena ovat valittujen vaihdetuotteiden planeettapyörästöjen eri kytkentämahdollisuudet ja niiden vaikutus toisiinsa. Vaihteiden teknistä toteutusta ja toimivuutta tarkastellaan fyysisten testien, simuloinnin sekä analyyttisen laskennan avulla. Apuna työssä on käytetty Dymola simulointiohjelmaa, jossa kinemaattisten kuvakeliitäntöjen avulla on rakennettu virtuaalimalli tarkastellusta tuotteesta ja sen toiminnasta. Tietokoneen avulla luotua dynaamista simulointimallia on muokattu tutkimuksen edistyessä differentiaalisesti jatkuvasäätöisen momentinmuuntimen aikaan saamiseksi. Tuotteissa on käytetty aurinkopyörällisiä ja aurinkopyörättömiä planeettapyörästöjä. Ensimmäisessä tutkittavassa tuotteessa on kolme planeettapyörästöä ja toisessa kaksi. Teholähteeksi käy polttomoottori tai sähkömoottori. Välitys- ja pyörimissuhteiden muuntoon vaikuttaa planeettavaihteistoon kytketty sähkömoottori, jonka toimintaa voidaan ohjata erikseen. Työssä on selvitetty, millaisia kulmanopeuksia ja momentteja eri ajanhetkellä ja eri pisteissä simulointimallia esiintyy.Lisäksi selvitetään vaihteistojen portaattoman välityssuhteen muuntomahdollisuudet. Tarkoituksena on saada realistista informaatiota tutkittavien laitteiden toiminnasta. Johtavana ajatuksena on modernien menetelmien käyttäminen uusien innovaatioiden toimivuuden ja äärikohtien tutkimiseksi.

Transmission ratio distortion in the human body louse, Pediculus humanus (Insecta : Phthiraptera)

We studied inheritance at three microsatellite loci in eight F-1 and two F-2 families of the body (clothes) louse of humans, Pediculus humanus. The alleles of heterozygous female-parents were always inherited in a Mendelian fashion in these families. Alleles from heterozygous male-parents, however, were inherited in two different ways: (i) in a Mendelian fashion and (ii) in a non-Mendelian fashion, where males passed to their offspring only one of their two alleles, that is, 100% nonrandom transmission. In male body lice, where there was non-Mendelian inheritance, the paternally inherited set of alleles was eliminated. We interpret this pattern of inheritance as evidence for extreme transmission ratio distortion of paternal alleles in this species.

Comparison study of two competing models of an all mechanical power transmission system

A comparison between two competing models of an all mechanical power transmission system is studied by using Dymola –software as the simulation tool. This tool is compared with Matlab/ Simulink –software by using functionality, user-friendliness and price as comparison criteria. In this research we assume that the torque is balanceable and transmission ratios are calculated. Using kinematic connection sketches of the two transmission models, simulation models are built into the Dymola simulation environment. Models of transmission systems are modified according to simulation results to achieve a continuous variable transmission ratio. Simulation results are compared between the two transmission systems. The main features of Dymola and MATLAB/ Simulink are compared. Advantages and disadvantages of the two softwares are analyzed and compared.

Transmission measurements using a new far-infrared set-up

A system comprised of a Martin-Puplett type polarizing interferometer and a Helium-3 cryostat was developed to study the transmission of materials in the very-far-infrared region of the spectrum. This region is of significant interest due to the low-energy excitations which many materials exhibit. The experimental transmission spectrum contains information concerning the optical properties of the material. The set-up of this system is described in detail along with the adaptations and improvements which have been made to the system to ensure the best results. Transmission experiments carried out with this new set-up for two different varieties of materials: superconducting thin films of lead and biological proteins, are discussed. Several thin films of lead deposited on fused silica quartz substrates were studied. From the ratio of the transmission in the superconducting state to that in the normal state the superconducting energy gap was determined to be approximately 25 cm-1 which corresponds to 2~/kBTc rv 5 in agreement with literature data. Furthermore, in agreement with theoretical predictions, the maximum in the transmission ratio was observed to increase as the film thickness was increased. These results provide verification of the system's ability to accurately measure the optical properties of thin low-Tc superconducting films. Transmission measurements were carried out on double deionized water, and a variety of different concentrations by weight of the globular protein, Bovine Serum Albumin, in the sol, gel and crystalline forms. The results of the water study agree well with literature values and thus further illustrate the reproducibility of the system. The results of the protein experiments, although preliminary, indicate that as the concentration increases the samples become more transparent. Some weak structure in the frequency dependent absorption coefficient, which is more prominent in crystalline samples, may be due to low frequency vibrations of the protein molecules.

Desempenho da colhedora de milho Penha CLM-350: parte I - sistema espigador

Com o propósito de avaliar a colhedora Penha CLM-350, visando fornecer subsídios aos projetos e usuários, realizou-se o presente trabalho, onde foi estudada a eficácia do sistema espigador, determinando-se a porcentagem de milho colhido para os diversos tratamentos estudados. Definiu-se um parâmetro adimensional U, que é a relação entre a velocidade periférica dos roletes e a velocidade de deslocamento da colhedora. Procurou-se relacionar as diversos tratamentos U, com os valores percentuais de grãos de milho colhidos e perdidos no solo. Os resultados foram estudados através da análise de variância, empregando-se o teste F, aos níveis de 1% e 5% de probabilidade e o teste Tukey para a comparação estatística entre as médias.

Uma análise da eficiência de uma transmissão CVT

This undergraduate thesis evaluates the effects of temperature variation of the air inside the CVT gearbox on the performance of a Continuously Variable Transmission (CVT). The CVT used in the tests was manufactured by Gaged Engineering (GX9 model) and is currently used in a Baja prototype. It’s a mechanically operated CVT, which the movement of the pulley plates varies according to the drive shaft rotation, shifting the belt along the diameter, and varying the transmission ratio. The purpose of this work is to analyze the change in the slip factor, coefficient that compares the variation between the actual transmission ratio and the ratio of geometric transmission, and its correlation with the power variation. A test bench was built and some tests were performed, indicating that was possible to achieve output power ratios of 1.75 [ℎ

Expression and function of $\beta$-1,4-galactosyltransferase during wild-type and T/{\it t\/} -mutant spermatogenesis

In the mouse, gamete recognition is mediated in part by the binding of sperm surface $\beta$1,4 galactosyltransferase (GalTase) to specific oligosaccharide residues on the zona pellucida ZP3. The expression of GalTase on the sperm surface is regulated by alleles within the distal segment of the T/t complex and results in a haploid-specific increase in GalTase expression on spermatids and sperm from t-bearing males, suggesting that differences in sperm GalTase activity may contribute to t-sperm transmission ratio distortion. In this study, the expression of GalTase RNA during wild-type and T/t-mutant spermatogenesis was characterized and the role of GalTase was analyzed in transmission ratio distortion. It was found that spermatogenic cells predominantly express the long form of the GalTase RNA, which encodes the GalTase protein that is preferentially targeted to the cell surface in somatic cells. In wild-type testes, GalTase RNA accumulates during the maturation of primary spermatocytes, reaches peak levels prior to meiosis, and decreases and meiosis. GalTase RNA accumulates to similar levels during the maturation of +/t and t/t primary spermatocytes, but unlike wild-type, the level of GalTase RNA in t-spermatocytes remains elevated during meiotic division. Consequently, spermatids in t-mutant testes inherit higher levels of GalTase RNA than do wild-type spermatids, which likely accounts for the haploid-specific increase in surface GalTase activity characteristic of spermatids from t-bearing mice.^ The functional significance of the increased GalTase activity during t-sperm transmission ratio distortion was determined by examining the distribution of GalTase RNA and surface GalTase protein in haploid spermatids from +/t males. Results show that +- and t-spermatids have similar levels of both GalTase RNA and protein, indicating that transmission ratio distortion in +/t mice is not likely due to haploid-specific differences in sperm surface GalTase activity.^ The presence of GalTase on the surface of an early spermatogenic cells before it is required on the mature sperm to perform its function during gamete binding suggests a separate function for GalTase in Sertoli-germ cell adhesion. Studies indicate that cell surface GalTase partly mediates the initial adhesion of pachytene spermatocytes, but not haploid spermatids, to Sertoli cells. ^

LC2, the Chlamydomonas Homologue of the t Complex-encoded Protein Tctex2, Is Essential for Outer Dynein Arm Assembly

Tctex2 is thought to be one of the distorter genes of the mouse t haplotype. This complex greatly biases the segregation of the chromosome that carries it such that in heterozygous +/t males, the t haplotype is transmitted to >95% of the offspring, a phenomenon known as transmission ratio distortion. The LC2 outer dynein arm light chain of Chlamydomonas reinhardtii is a homologue of the mouse protein Tctex2. We have identified Chlamydomonas insertional mutants with deletions in the gene encoding LC2 and demonstrate that the LC2 gene is the same as the ODA12 gene, the product of which had not been identified previously. Complete deletion of the LC2/ODA12 gene causes loss of all outer arms and a slow jerky swimming phenotype. Transformation of the deletion mutant with the cloned LC2/ODA12 gene restores the outer arms and rescues the motility phenotype. Therefore, LC2 is required for outer arm assembly. The fact that LC2 is an essential subunit of flagellar outer dynein arms allows us to propose a detailed mechanism whereby transmission ratio distortion is explained by the differential binding of mutant (t haplotype encoded) and wild-type dyneins to the axonemal microtubules of t-bearing or wild-type sperm, with resulting differences in their motility.

Mecanismos de transmissão de preços e parcelas de mercado: uma análise sobre as exportações brasileiras de manga

Climate and environmental conditions allowed Brazil to become one of the largest producers of tropical fruits in the world. The São Francisco Valley, over the years, has emerged as the main fruit-producing region of the country, especially mangos and grapes. The mango, which is produced in this region, has reached a good international position, especially in European and American markets. However, the domestic price has absorbed more and more the impact of fluctuations in the international market expectations affecting the production and marketing of producers. The objective of the study is to analyze the transmission ratio of export prices of the mango, with the American market prices and the European Union in the period from 2003 to 2013. It is intended also to analyze the factors affecting the fluctuations of exports Brazilian mango for the main import markets. To achieve the proposed objectives, we used, in the methodology, the autoregressive vector model, in order to find the price transmission mechanism and the mechanisms of impacts through the impulse response function. We also used, the Constant Market Share model, in order to observe the importance of the effects competitiveness, destination, and growth in world trade on the changes of Brazilian mango exports in the period. The data used were obtained from the database of the Ministry of Development and Foreign Trade - MIDIC and FAOSTAT (Food and Agriculture Organization of the United Nations). Among the results, it was found that the Brazilian domestic prices are influenced by the US market price, and that price shocks promoted this market can impact on the growth of the internal prices for several months. It was noted also that the competitiveness effect accounted for the largest portion of the effective growth of Brazilian exports, in other word, the country has improved its competitiveness among the other exporting countries.

CP-OQAM-OFDM based SC-FDMA: adjustable user bandwidth and space-time coding

The discrete Fourier transmission spread OFDM DFTS-OFDM) based single-carrier frequency division multiple access (SC-FDMA) has been widely adopted due to its lower peak-to-average power ratio (PAPR) of transmit signals compared with OFDM. However, the offset modulation, which has lower PAPR than general modulation, cannot be directly applied into the existing SC-FDMA. When pulse-shaping filters are employed to further reduce the envelope fluctuation of transmit signals of SC-FDMA, the spectral efficiency degrades as well. In order to overcome such limitations of conventional SC-FDMA, this paper for the first time investigated cyclic prefixed OQAMOFDM (CP-OQAM-OFDM) based SC-FDMA transmission with adjustable user bandwidth and space-time coding. Firstly, we propose CP-OQAM-OFDM transmission with unequally-spaced subbands. We then apply it to SC-FDMA transmission and propose a SC-FDMA scheme with the following features: a) the transmit signal of each user is offset modulated single-carrier with frequency-domain pulse-shaping; b) the bandwidth of each user is adjustable; c) the spectral efficiency does not decrease with increasing roll-off factors. To combat both inter-symbolinterference and multiple access interference in frequencyselective fading channels, a joint linear minimum mean square error frequency domain equalization using a prior information with low complexity is developed. Subsequently, we construct space-time codes for the proposed SC-FDMA. Simulation results confirm the powerfulness of the proposed CP-OQAM-OFDM scheme (i.e., effective yet with low complexity).

Long-term potentiation of synaptic transmission in the avian hippocampus

The avian hippocampus plays a pivotal role in memory required for spatial navigation and food storing. Here we have examined synaptic transmission and plasticity within the hippocampal formation of the domestic chicken using an in vitro slice preparation. With the use of sharp microelectrodes we have shown that excitatory synaptic inputs in this structure are glutamatergic and activate both NMDA-and AMPA-type receptors on the postsynaptic membrane. In response to tetanic stimulation, the EPSP displayed a robust long-term potentiation (LTP) lasting >1 hr. This LTP was unaffected by blockade of NMDA receptors or chelation of postsynaptic calcium. Application of forskolin increased the EPSP and reduced paired-pulse facilitation: (PPF), indicating an increase in release probability. In contrast, LTP was not associated with a change in the PPF ratio. Induction of LTP did not occlude the effects of forskolin. Thus, in contrast to NMDA receptor-independent LTP in the mammalian brain, LTP in the chicken hippocampus is not attributable to a change in the probability of transmitter release and does not require activation of adenylyl cyclase, These findings indicate that a novel form of synaptic plasticity might underlie learning in the avian hippocampus.

Epidemiological and molecular evidence supports the zoonotic transmission of Glardia among humans and dogs living in the same community

Giardia duodenalis isolates recovered from humans and clogs living in the same locality in a remote tea-growing community of northeast India were characterized at 3 different loci; the SSU-rDNA, elongation factor 1-alpha (ef1-alpha) and triose phosphate isomerase (tpi) gene. Phylogenetic analysis of the SSU-rDNA and ef1-alpha genes provided poor genetic resolution of the isolates within various assemblages, stressing the importance of using multiple loci when inferring genotypes to Giardia. Analysis of the tpi gene provided better genetic resolution and placed canine Giardia isolates within the genetic groupings of human isolates (Assemblages A and B). Further evidence for zoonotic transmission was supported by epidemiological data showing a highly significant association between the prevalence of Giardia in humans and presence of it Giardia-positive dog in the same household (odds ratio 3.01, 95%) CI, 1.11, 8.39, P = 0.0000).

Knowledge and practices of medical students to prevent tuberculosis transmission in Rio de Janeiro, Brazil

Objectives. To describe knowledge, practices, and associated factors of medical students to prevent transmission of tuberculosis (TB) in five medical schools. Methods. Cross-sectional survey of undergraduate medical students in preclinical and in early and late clinical years. Information was obtained on sociodemographic profile, previous lectures on TB, knowledge about TB transmission, exposure to patients with active pulmonary TB, and use of respiratory protective masks. Results. Among 1 094 respondents, 575 (52.6%) correctly answered that coughing, speaking, and sneezing can transmit TB. Early [adjusted odds ratio = 4.0 (3.0, 5.5)] and late [adjusted odds ratio = 4.2 (3.1, 5.8)] clinical years were associated with correct answers, but having had previous lectures on TB was not. Among those who had previous lectures on TB, the rate of correct answers increased from 42.1% to 61.6%. Among 332 medical students who reported exposure to TB patients, 194 (58.4%) had not used protective masks. More years of clinical experience was associated with the use of masks [adjusted odds ratio = 2.9 (1.4, 6.1)], while knowledge was inversely associated with the use of masks [adjusted odds ratio = 0.4 (0.2, 0.6)]. Conclusions. Many medical students are not aware of the main routes of TB infection, and lectures on TB are not sufficient to change knowledge and practices. Regardless of knowledge about TB transmission, students engage in risky behaviors: more than two-thirds do not use a protective mask when examining an active TB case. We suggest innovative, effective active learning experiences to change this scenario.

Malaria transmission model for different levels of acquired immunity and temperature-dependent parameters (vector)

OBJECTIVE: Describe the overall transmission of malaria through a compartmental model, considering the human host and mosquito vector. METHODS: A mathematical model was developed based on the following parameters: human host immunity, assuming the existence of acquired immunity and immunological memory, which boosts the protective response upon reinfection; mosquito vector, taking into account that the average period of development from egg to adult mosquito and the extrinsic incubation period of parasites (transformation of infected but non-infectious mosquitoes into infectious mosquitoes) are dependent on the ambient temperature. RESULTS: The steady state equilibrium values obtained with the model allowed the calculation of the basic reproduction ratio in terms of the model's parameters. CONCLUSIONS: The model allowed the calculation of the basic reproduction ratio, one of the most important epidemiological variables.

Correlation between HIV and HCV in Brazilian prisoners: evidence for parenteral transmission inside prison

OBJECTIVE: It is an accepted fact that confinement conditions increase the risk of some infections related to sexual and/or injecting drugs practices. Mathematical techniques were applied to estimate time-dependent incidence densities of HIV infection among inmates. METHODS: A total of 631 prisoners from a Brazilian prison with 4,900 inmates at that time were interviewed and their blood drawn. Risky behavior for HIV infection was analyzed, and serological tests for HIV, hepatitis C and syphilis were performed, intended as surrogates for parenteral and sexual HIV transmission, respectively. Mathematical techniques were used to estimate the incidence density ratio, as related to the time of imprisonment. RESULTS: Prevalence were: HIV -- 16%; HCV -- 34%; and syphilis -- 18%. The main risk behaviors related to HIV infection were HCV prevalence (OR=10.49) and the acknowledged use of injecting drugs (OR=3.36). Incidence density ratio derivation showed that the risk of acquiring HIV infection increases with the time of imprisonment, peaking around three years after incarceration. CONCLUSIONS: The correlation between HIV and HCV seroprevalence and the results of the mathematical analysis suggest that HIV transmission in this population is predominantly due to parenteral exposure by injecting drug, and that it increases with time of imprisonment.