Design of multichannel nonrecursive digital filters with applications to seismic reflection data

Imperial Users onl

Maths instruction in vocational high school from teachers and students’ eyes: a different kettle of fish

Mathematics course in vocational high school education is significant worldwide to equip vocational students with the technical and personal skills that are required for the effective workforce as discussed in the context of Science, Technology, Engineering and Mathematics (STEM) education. The present research sets out to investigate 20 Turkish maths teachers’ belief and instructional practices through comparing vocational students’ perceptions for mathematics instruction and the researcher’s observation in a state vocational high school, which is under- researched. 20 maths teachers and 161 students participated in this longitudinal study (n=181). Mixed methods were used, and three types of data were collected as follows: questionnaires, interviews and observation for triangulation of data and methods t for the reliability and validity of the study. The findings indicated that maths teachers’ belief and practices were not consistent when compared with the questionnaire and interview data collected from vocational students, and also observation carried out by the researcher.Keywords: mathematics education, vocational high school, vocational students, beliefs and practice

erectile function after radical prostatectomy

In this study our aim is to increase the understanding of the prostate and related organs anatomy for better continence and erectile function results after urological surgery. Prostate and related organs were dissected from seven cadavers. After dissection, 165 serial sections with 300 mu m thickness were derived at a 100 mu m interval. The histological images were examined and imported to the computer. Three-dimensional (3D) remodeling had been performed. The findings were evaluated into three categories: macroscopic, microscopic and 3D reconstruction. Striated muscle fibers had been detected at the anterior fibromuscular stroma in histological sections. In 3D remodeling, urethra seemed to be a complete functional unit, beginning from the trigone up to the membranous urethra. The neurovascular bundles run under the pelvic fascia on both sides and go through to the bladder neck at 5 and 7 o'clock. Computer remodeling demonstrated that neurovascular structures had a close association with the bladder neck and the seminal vesicle. Computer program made it possible to rotate all 3D-reconstructed figures by 3601 and examine them from all possible angles. All reconstructed structures can be examined together at the same time or one by one. Surgeons must pay special attention to the continence area described as a single unit, beginning from trigone to the membranous urethra, during the surgery. Meticulous dissection of the neurovascular bundles, especially close to the seminal vesicles and bladder neck, during the radical prostatectomy is necessary. These reconstructions can be used for the educational purpose of medical students as well as the urology surgeons

Energy absorption in lattice structures in dynamics: Nonlinear FE simulations

An experimental study of the stress–strain behaviour of titanium alloy (Ti6Al4V) lattice structures across a range of loading rates has been reported in a previous paper [1]. The present work develops simple numerical models of re-entrant and diamond lattice structures, for the first time, to accurately reproduce quasi-static and Hopkinson Pressure Bar (HPB) test results presented in the previous paper. Following the development of lattice models using implicit and explicit non-linear finite element (FE) codes, the numerical models are first validated against the experimental results and then utilised to explore further the phenomena associated with impact, the failure modes and strain-rate sensitivity of these materials. We have found that experimental results can be captured with good accuracy by using relatively simple numerical models with beam elements. Numerical HPB simulations demonstrate that intrinsic strain rate dependence of Ti6Al4V is not sufficient to explain the emergent rate dependence of the re-entrant cube samples. There is also evidence that, whilst re-entrant cube specimens made up of multiple layers of unit cells are load rate sensitive, the mechanical properties of individual lattice structure cell layers are relatively insensitive to load rate. These results imply that a rate-independent load-deflection model of the unit cell layers could be used in a simple multi degree of freedom (MDoF) model to represent the impact behaviour of a multi-layer specimen and capture the microscopic rate dependence

Effects of different irrigation programs on yield and quality parameters of eggplant (Solanum melongena L.) under greenhouse conditions

This study was carried out to determine the effects of different irrigation programs on yield and quality parameters of eggplant under greenhouse conditions, using Class A pan evaporation calculations and different plant-pan coefficients. Irrigation water was applied through drip irrigation method twice a week during the growing period. Irrigation treatments consisted of five plant-pan coefficients (S1: kcp = nonirrigation, S2: kcp = 0.50, S3: kcp = 0.75, S4: kcp = 1.00 and S5: kcp = 1.25). The amount of irrigation water ranged between 95.2 and 238.7 mm among the treatments. Evapotranspiration (ET) values varied from 93.1 to 466.3 mm for the treatments. The highest yield was obtained from the S3 and S4 treatments. A significant polynomial correlation was obtained between the yield and irrigation water, and between the yield and ET (P < 0.01). This indicated that when irrigation water and ET increased, yield also increased to a certain point. However, when the amount of irrigation water exceeded the plant water requirement, eggplant yield decreased. Yield response factor (Ky) was determined as 0.81. Since Ky < 1, eggplants were not sensitive to water deficiency. In addition, the highest water use efficiency (WUE) and irrigation water use efficiency (IWUE) values were calculated in the S3 (12.9 kgm-3) and S2 (44.2 kgm-3) treatments, while the lowest WUE and IWUE values were calculated in the S5 (7.9 and 15.5 kgm-3) treatment to which the highest irrigation water was applied. This finding indicated that WUE and IWUE values decreased with the increasing irrigation water and ET. These results suggested that S3 (kcp = 0.75) treatment can be the most appropriate irrigation program for eggplant with higher yield and WUE under greenhouse conditions.Key words: Eggplant, yield response factor, water use efficiency, Class A pan, evapotranspiration