MODELING A COMPUTER APPLICATION FOR MANAGEMENT OF MAINTENANCE ACTIVITIES OF UNPAVED ROADS

ABSTRACTThis study presents a contribution to the modeling of a computer application employing a method of serviceability performance for unpaved roads, aiming the management of maintenance/restoration activities of the primary surface layer. The proposed methodology consisted of field inspections during dry (April to September) and rainy (October to March) periods, during which objective evaluations were performed to survey of defects and their densities and degrees of severity. To aid the functional classification of analyzed road sections and the determination of the defect with major influence on the serviceability of these roads, the method of serviceability performance proposed by Silva (2009)was implemented in the Visual Basic for Applications (VBA) language in Microsoft Excel software. With the use of the computer application proposed it was possible to identify among the defects analyzed in field, through the index of serviceability of the sampling unit per defect type (ISUdef), which one had the greatest influence on determining the relative serviceability index per road section (IST). The results allow us to conclude that the computer application Road achieved satisfactory results, since the objective evaluation criteria applied to road sections denotes consistency regarding their serviceability.

Polarímetro virtual: desenvolvimento, utilização e avaliação de um software educacional

Optical activity is the ability of chiral substances to rotate the plane of plane-polarized light and is measured using an instrument called a polarimeter. An educational software application to explore, both interactively and visually, the concepts related to polarimetry to facilitate their understanding was developed. The software was field-tested and a questionnaire evaluating the graphics interface, usability and the software as an educational tool, was answered by students. The results characterized the computer application developed as an auxiliary tool for assisting teachers in lectures and students in the learning process.

Ressonância: desenvolvimento, utilização e avaliação de um software educacional

Resonance is a useful concept that shows how electrons are shared between two or more atoms and allows a prediction of the chemical reactivity and relative stability of reagents, intermediates, and products. An educational software that enables interactive exploration of the concepts related to resonance and thereby facilitates its understanding was developed. The software was field-tested, and an evaluation questionnaire concerning the software as an educational tool was answered by the students and professors involved in the test. The results led to the conclusion that the developed computer application can be characterized as an auxiliary tool that assists teachers in their lectures and students in their learning process.

INTERACTIONS: DESIGN, IMPLEMENTATION AND EVALUATION OF A COMPUTATIONAL TOOL FOR TEACHING INTERMOLECULAR FORCES IN HIGHER EDUCATION

Intermolecular forces are a useful concept that can explain the attraction between particulate matter as well as numerous phenomena in our lives such as viscosity, solubility, drug interactions, and dyeing of fibers. However, studies show that students have difficulty understanding this important concept, which has led us to develop a free educational software in English and Portuguese. The software can be used interactively by teachers and students, thus facilitating better understanding. Professors and students, both graduate and undergraduate, were questioned about the software quality and its intuitiveness of use, facility of navigation, and pedagogical application using a Likert scale. The results led to the conclusion that the developed computer application can be characterized as an auxiliary tool to assist teachers in their lectures and students in their learning process of intermolecular forces.

Weather requirements and rain forecast to time fungicide application for Fusarium head blight control in wheat

The aim of this study was to determine the minimum conditions of wetness duration and mean temperature required for Fusarium head blight infection in wheat. The weather model developed by Zoldan (2008) was tested in field experiments for two wheat cultivars grown in 2005 (five sowing dates) and 2006 (six sowing dates) in 10 m² plots with three replicates. The disease was assessed according to head incidence (HI), spikelet incidence (SI), and the interaction between these two methods was called head blight severity (HBS). Starting at the beginning of anthesis, air temperature and head wetness duration were daily recorded with an automatic weather station. With the combination of these two factors, a weather favorability table was built for the disease occurrence. Starting on the day of flowering beginning (1 - 5% fully exserted anthers), the sum of daily values for infection favorability (SDVIF) was calculated by means of a computer program, according to Zoldan (2008) table. The initial symptoms of the disease were observed at 3.7% spikelet incidence, corresponding to 2.6 SVDFI. The infection occurs in wheat due to rainfall which results in spike wetting of > 61.4 h duration. Rainfall events forecast can help time fungicide application to control FHB. The name of this alert system is proposed as UPF-scab alert.

Computer programs for analysis of droplets sprayed on water sensitive papers

The use of water-sensitive papers is an important tool for assessing the quality of pesticide application on crops, but manual analysis is laborious and time-consuming. Thus, this study aimed to evaluate and compare the results obtained from four software programs for spray droplet analysis in different scanned images of water-sensitive papers. After spraying, papers with four droplet deposition patterns (varying droplet spectra and densities) were analyzed manually and by means of the following computer programs: CIR, e-Sprinkle, DepositScan and Conta-Gotas. The diameter of the volume and number medians and the number of droplets per target area were studied. There is a strong correlation between the values measured using the different programs and the manual analysis, but there is a great difference between the numerical values measured for the same paper. Thus, it is not advisable to compare results obtained from different programs.