The temperature in the drilling of ex-vivo bovine femurs and human cadaveric tibiae

The bone drilling is common in orthopaedic surgery. The success of this surgery is dependent on many factors, namely on the heat generation control during the bone drilling. The main concern in bone drilling is the mechanical and thermal damage induced by inappropriate parameters, as drill speed and feed-rate.info:eu-repo/semantics/publishedVersio

Dengue disease, basic reproduction number and control

Dengue is one of the major international public health concerns. Although progress is underway, developing a vaccine against the disease is challenging. Thus, the main approach to fight the disease is vector control. A model for the transmission of Dengue disease is presented. It consists of eight mutually exclusive compartments representing the human and vector dynamics. It also includes a control parameter (insecticide) in order to fight the mosquito. The model presents three possible equilibria: two disease-free equilibria (DFE) and another endemic equilibrium. It has been proved that a DFE is locally asymptotically stable, whenever a certain epidemiological threshold, known as the basic reproduction number, is less than one. We show that if we apply a minimum level of insecticide, it is possible to maintain the basic reproduction number below unity. A case study, using data of the outbreak that occurred in 2009 in Cape Verde, is presented.Comment: This is a preprint of a paper whose final and definitive form has appeared in International Journal of Computer Mathematics (2011), DOI: 10.1080/00207160.2011.55454

First in-beam studies of a Resistive-Plate WELL gaseous multiplier

We present the results of the first in-beam studies of a medium size (10$\times$10 cm$^2$) Resistive-Plate WELL (RPWELL): a single-sided THGEM coupled to a pad anode through a resistive layer of high bulk resistivity ($\sim$10$^9 \Omega$cm). The 6.2~mm thick (excluding readout electronics) single-stage detector was studied with 150~GeV muons and pions. Signals were recorded from 1$\times$1 cm$^2$ square copper pads with APV25-SRS readout electronics. The single-element detector was operated in Ne\(5% $\mathrm{CH_{4}}$) at a gas gain of a few times 10$^4$, reaching 99$\%$ detection efficiency at average pad multiplicity of $\sim$1.2. Operation at particle fluxes up to $\sim$10$^4$ Hz/cm$^2$ resulted in $\sim$23$\%$ gain drop leading to $\sim$5$\%$ efficiency loss. The striking feature was the discharge-free operation, also in intense pion beams. These results pave the way towards robust, efficient large-scale detectors for applications requiring economic solutions at moderate spatial and energy resolutions.Comment: Accepted by JINS

OPTIMASI PENJADWALAN MATA KULIAH FAKULTAS ILMU KOMPUTER UNIVERSITAS KATOLIK SANTO THOMAS SUMATERA UTARA DENGAN MENGGUNAKAN ALGORITMA GENETIKA

Abstrak Pada penelitian ini dilakukan pengembangan sistem aplikasi penjadwalan mata kuliah dengan mengimplementasikan algoritma genetika. Sebagai ujicoba kemampuan sistem yang dikembangkan untuk pembuatan jadwal mata kuliah, digunakan datamata kuliah pada Fakultas Ilmu KomputerUniversitas Katolik Santo Thomas. Implementasi perangkat lunak yang dikembangkan, diujicobakan pada tiga kelompok data dengan jumlah mata kuliah setiap kelompok data berbeda-beda. Dari ujicoba ketiga kelompok data didapatkan hasil yakni, algoritma genetika cukup baik digunakan sebagai algoritma membuat jadwal mata kuliah, hal ini dapat dilihat dari hasil ujicoba I sampai dengan ujicoba III yang telah dilakukan. Keberhasilan ini dapat dilihat dari nilai fitness sama dengan nol yang dihasilkan setiap kali ujicoba, yang menandakan bahwa jadwal yang dihasilkan sudah tidak ada bentrok

Micromegas operation in high pressure xenon: charge and scintillation readout

The operational characteristics of a Micromegas operating in pure xenon at the pressure range of 1 to 10 bar are investigated. The maximum charge gain achieved in each pressure is approximately constant, around 4x10^2, for xenon pressures up to 5 bar and decreasing slowly above this pressure down to values somewhat above 10^2 at 10 bar. The MM presents the highest gains for xenon pressures above 4 bar, when compared to other micropattern gaseous multipliers. The lowest energy resolution obtained for X-rays of 22.1 keV exhibits a steady increase with pressure, from 12% at 1bar to about 32% at 10 bar. The effective scintillation yield, defined as the number of photons exiting through the MM mesh holes per primary electron produced in the conversion region was calculated. This yield is about 2x10^2 photons per primary electron at 1 bar, increasing to about 6x10^2 at 5 bar and, then, decreasing again to 2x10^2 at 10 bar. The readout of this scintillation by a suitable photosensor will result in higher gains but with increased statistical fluctuations.Comment: 22 pages, 11 figure

THGEM-based detectors for sampling elements in DHCAL: laboratory and beam evaluation

We report on the results of an extensive R&D program aimed at the evaluation of Thick-Gas Electron Multipliers (THGEM) as potential active elements for Digital Hadron Calorimetry (DHCAL). Results are presented on efficiency, pad multiplicity and discharge probability of a 10x10 cm2 prototype detector with 1 cm2 readout pads. The detector is comprised of single- or double-THGEM multipliers coupled to the pad electrode either directly or via a resistive anode. Investigations employing standard discrete electronics and the KPiX readout system have been carried out both under laboratory conditions and with muons and pions at the CERN RD51 test beam. For detectors having a charge-induction gap, it has been shown that even a ~6 mm thick single-THGEM detector reached detection efficiencies above 95%, with pad-hit multiplicity of 1.1-1.2 per event; discharge probabilities were of the order of 1e-6 - 1e-5 sparks/trigger, depending on the detector structure and gain. Preliminary beam tests with a WELL hole-structure, closed by a resistive anode, yielded discharge probabilities of <2e-6 for an efficiency of ~95%. Methods are presented to reduce charge-spread and pad multiplicity with resistive anodes. The new method showed good prospects for further evaluation of very thin THGEM-based detectors as potential active elements for DHCAL, with competitive performances, simplicity and robustness. Further developments are in course.Comment: 15 pages, 11 figures, MPGD2011 conference proceedin

Ação de estimulante vegetal em cafeeiro (Coffea arabica cv. Mundo Novo) e soja (Glycine max cv. Biloxi)

This experiment was carried out with the objective of determine the effect of a plant stimulant (Respond or Reward) in the productivity of Coffea arabica cv. Mundo Novo and Glycine max cv. Biloxi under field conditions. In the experimental field of E.S.A. "Luiz de Queiroz" in Piracicaba, São Paulo State, it was applied Respond in the concentrations of 1,0 1.ha-1 and 1,5 1.ha-1 (January, 17), 1,0 1.ha-1 (January, 17 and March, 17), 1,0 1.ha-1 and 1,5 1.ha-1 (March, 17), and check treatment. The solutions of the plant stimulant were sprayed in the leaves of the plant until run-off stage. Respond 1,0 1.ha-1 sprayed in January, 17 and March, 17 increased dry fruits percent, observed in June, 12. Respond 1,5 1. ha-1 (March, 17) promoted increase in the immature fruits percent observed in July, 16; at this time Respond 1,0 1.ha-1 applied in January, 17 increased dry fruits percent. Application of the plant stimulant 1,0 1.ha-1 in March, 17 and 1,0 1.ha-1 in January, 17 and March 17, increased the number of fruits in August, 23. In April, 30 it was realized the application of Respond 1,0 1.ha-1 and 1,5 1 . ha-1 in soybean. It was observed a tendency of Respond reduced the parameters of production and increased the intrinsic parameters of the pods.Este experimento foi realizado com a finalidade de determinar o efeito do estimulante vegetal Respond, na produtividade do cafeeiro (Coffea arabica cv. Mundo Novo) e soja (Glycine max cv. Biloxi), em condições de campo. Nos campos experimentais da E.S.A. "Luiz de Queiroz", em Piracicaba (SP), aplicou-se Respond nas dosagens de 1,0 1 . ha-1 e 1,5 1 . ha-1 (17/01/86) , 1,0 1 ha-1 (17/01 e 17/03), 1,0 1.ha-1 e 1,5 1 .ha-1 (17/03), além do controle. Respond 1 1.ha-1, pulverizado em 17/01 e 17/03 aumentou a porcentagem de frutos secos observados em 12/06. Respond 1,5 1.ha-1 (17/03) promoveu incremento na porcentagem de frutos verdes notados em 16/07; nesta data Respond 1,0 1.ha-1 aplicado em 17/01 e 17/03, 1,5 e 1,0 1. ha-1 aplicados em 17/01 aumentaram a porcentagem de frutos secos. Aplicação do estimulante vegetal 1,0 1.ha-1 em 17/03 e 1,01.ha-1 em 17/01 e 17/03, incrementaram o número de frutos secos em 23/08. Em 30/04/86 foram realizadas pulverizações em soja 'Biloxi' com Respond 1,0 1.ha-1 e 1,5 1.ha-1, além do controle. Na colheita (01/07) determinou-se o peso verde médio das vagens/parcela (10 plantas), número médio de vagens/parcela, peso médio das sementes / parcela, peso médio das sementes/vagem, número médio das sementes/vagem e peso médio da parte aérea da planta de soja desprovida das vagens. Constatou-se uma tendência de Respond reduzir os parâmetros de produção e aumentar os parâmetros intrínsecos das vagens de soja