ANALYSIS OF THE GAINS IN THE WORKSTATIONS OF AN AUTOMOTIVE INDUSTRY FROM AN ERGONOMICS-BASED TIME AND MOTION STUDY

High-efficiency manufacturing has been one of the main goals of companies, requiring the use of adequate techniques and tools with high value and low cost to increase productivity. In this case, industrial companies focus on increasing productivity without losing quality in services and products, using adequate techniques without high investments to avoid compromising the final result. This study applies time and motion study techniques to two workstations of a specific automotive industry. Accordingly, ergonomics data on specific tasks are collected, with satisfactory results. The method proposed simplifications in workstations, reduces times, and, therefore, increases productivity.

Estimation of rainfall based on remote sensing and observation fields in Jaru Biological Reserve at the Brazilian Amazonian forest

The Amazon basin, with a drainage area of about 6 million km2, is the largest drainage basin in the world, consequently the accurate measuring the rainfall dynamics at high spatial and temporal resolution is essential for a better understanding of the hydrological cycle. So, we validated rainfall estimates from the Tropical Rainfall Measuring Mission (TRMM) satellite using surface precipitation data collected from 2004 to 2012. Rainfall data came from the Jaru Biological Reserve meteorological station, located to the east in the state of Rondônia, Brazil, and was compared with the estimates of the algorithms 3B42 V7 and 3B43 V7 of the product TRMM. Statistical analysis was based on indices of continuous variables such as the Spearman correlation coefficient (ρ), the square root mean square error normalized by the mean of the observed values ​​(NRMSE), the mean square error (RMSE), the error (ERV) and some categorical indices such as probability of detection (POD), False Alarm (FAR) and success rate (CSI) between the daily and monthly precipitation observed data and the estimated precipitation data. The 3B43 V7 precipitation estimates were broadly representative of surface observations, but underestimated precipitation in the wet season and overestimated precipitation in the dry season. The 3B42 V7 product performed poorly and does not generate a robust representation of surface precipitation.

A SIMPLE PATTERN RECOGNITION-BASED METHOD FOR POWER QUALITY DISTURBANCE DETECTION

Voltage disturbances are the most frequent cause of a large range of disruption in industrial, commercial, and residential power supply systems. These disturbances are often referred to as power quality problems and affect the Power Systems causing substantial losses. To avoid the storage of a large amount of data, the first task in monitoring the power quality is the realtime detection of disturbances, which must be performed by an accurate and low-complexity system. This paper proposes a low-complexity system for power quality disturbance detection. The method makes innovative use of simple features extracted from reduced segments of the monitored voltage waveform. The extract features (the mean value, variance, energy, and the maximum and minimum values of the filtered voltage signals) require low computational effort and allow a considerable dimensional reduction of the signals, leading to simple detection algorithms. The proposed method achieves high detection rates on both simulated and real signals.

THERMOCAPILLARY MONITORING USING PARTICLE IMAGE VELOCIMETRY ASSOCIATED WITH DYNAMIC LASER SPECKLE

Thermocapillarity is a physical phenomenon used in many industrial processes, mainly in the field of miniaturization. Thermocapillary forces are the base of thermocapillary pumping (TCP), in which a drop of liquid moves through a microchannel or flat surface after temperature gradient occurs. The objective of this work was to study the thermocapillary convection during pumping without inserting external particles, monitored by the Particle Image Velocimetry (PIV) technique. The experiment consisted of a Pasteur tube containing a yellow fluorescein solution (0.02, 0.04, 0.06, 0.08, and 0.1 Molar), illuminated by a laser beam of 545 nm, 40 mW. After 2 minutes of illumination, the thermocapillary movement occurred at a distance of 0.05 mm below the meniscus when using a laser beam of 545 nm, 3 mW. The images were captured by a charge-coupled device (CCD) camera and processed using the PIV technique. The results showed an internal conversion capacity between the intersystem crossing, vibrational, and relaxation phenomena, also demonstrating the potential for applying the proposed approach. The images presented velocity distribution caused by thermocapillarity. The PIV was a useful tool for convective flow analysis if connected to appropriate image processing and enhancement techniques. In conclusion, the research showed the images with velocity distribution caused by thermocapillarity.

BIOSPECKLE LASER TO MONITOR THE GERMINATION OF ANGICO-VERMELHO SEEDS

Seed viability is an important parameter in its germination and in the establishment of seedlings, as well as for maintaining a seed bank, mainly for forest seeds, since they are responsible for the maintenance and perpetuation of plant communities and are a basic input for ecosystem recovery and conservation programs. To assess germination, traditional techniques use hundreds of seeds in a destructive manner, obtaining results after many days and can express the analyst’s subjectivity. The use of the Biospeckle Laser to monitor seed germination allows the analysis to be objective, fast, non-invasive, and automated analysis. This work proposed to measure the viability of Angico-Vermelho seeds during the first 72 hours of germination using the Biospeckle Laser with numerical analysis. The results obtained in the first experiment allowed monitoring of biological activity throughout the 72 hours of germination, showing high cell activity in the embryo region already in the first 4 hours of germination. In the second experiment, the results showed greater biological activity in the mature seeds when compared to immature ones during the first 4 hours of germination, also detailing the biological activity in different areas of the Angico-Vermelho seed, reporting a greater biological activity in the embryonic axis region when compared to the endosperm. In conclusion, the Biospeckle Laser technique with numerical AVD analysis can be used to analyze the germination of of A. colubrina already in the first 4 hours of germination, dispensing with traditional methods. This technique allows to study the seed germination in different regions and at different times.

VIBRATION LEVEL EVALUATION OF ENGINES FUELED WITH BRAZILIAN COMMERCIAL DIESEL AND BIODIESEL

This paper is aimed to analyze vibrations from engines fueled with two different fuels, Brazilian commercial diesel (B8) and Biodiesel (B100). Consumption, level of particulate matter emissions and engine temperature were also analyzed. The experiments were performed considering noninvasive tests in a diesel engine, taking into account three different speeds: 800 rpm, 1800 rpm and 3600 rpm. Results showed that the engine energetic loss from vibration signals collected allowed a quantitative assessment of how each fuel influenced the engine vibration level. In the three analyzed speeds, B8 diesel fuel showed be more energetic when compared to B100 biodiesel fuel. Although the consumption using B100 biodiesel fuel presented higher values than B8, the level of particulate matter emissions was lower than commercial diesel B8. It was also noted that the vibration increased in both cases when the engine speed increased. B8 diesel presented a total vibration varying according to speeds range, from 4.5% to 21% higher than B100 biodiesel. Therefore, the dissipated vibration energy using B8 diesel was higher (10% to 45%) than B100 biodiesel. It is concluded that combustion is one of the item that generates higher level of vibration in diesel engines and it depends on the kind of fuel used.

MEAN SURFACE TEMPERATURE OF JAPANESE QUAIL EXPOSED TO DIFFERENT LEVELS OF AIR VELOCITY AND TEMPERATURE AT START OF LAY

The objective of this study was to evaluate the effect of different air velocities and temperature at the feeder on mean surface temperature of Japanese quail during the initial stage of laying. The experiment was carried out at the Center for Research in Environment and Agroindustry Systems Engineering (AMBIAGRO), Department of Agricultural Engineering, Federal University of Viçosa, Viçosa/MG, Brazil. A total of 216 Japanese quail in the initial laying phase were placed in four environmental chambers with different temperatures and air velocity, where they were housed and distributed randomly in 2 galvanized wire cages, with 3 partitions each and 27 birds/cage, and a density of approximately 155.6 cm²/bird. The experimental design consisted of randomized blocks with replications of two treatments (air velocity at the feeder: 0, 1, 2, and 3 m/s and air temperature: 17, 23, 29 and 35°C). The mean surface temperature was analyzed by Two-Way ANOVA, with treatment means separated by the Tukey test (P < 0.05). There was a significant positive correlation between air temperature and mean surface temperature (MST). Air velocity is important in removing heat from the surface of birds.

USE OF THE FUZZY CLUSTERING ALGORITHM FOR PATTERN RECOGNITION IN FEED CONSUMPTION DATA OF PURE NEW ZEALAND WHITE RABBITS EXPOSED TO VARIED THERMAL CHALLENGES

The performance of New Zealand White rabbits (NZW) is directly associated with to ambiance-related factors because they present high sensitivity to high-temperature conditions. The objective of the present work was to use the Fuzzy C-Means (FCM) clustering algorithm for pattern recognition in daily feed consumption (CDR) of NZW rabbits exposed to different thermal challenges. The experiment was carried out in four air-conditioned wind tunnels installed in a laboratory. Twenty-four pure rabbits of the NZW breed aged 30 to 37 days were used. The experiment was carried out in two stages with a period of seven days each, and, at each stage, four dry bulb temperatures (20°C, 24ºC, 28ºC and 32ºC) were tested from the 30th day of the rabbits’ life. Data on CDR (kilo, kg day-1) were obtained by weighing the quantities supplied and the leftovers obtained daily from each rabbit in each treatment. Afterward, the Fuzzy C-Means algorithm (FCM) was used to classify the results. Also, to validate the analysis, the validation indexes were applied to indicate in which quantities of clusters the best partition results were obtained for this database. Thus, FCM cluster analysis was set up as a methodology capable of providing information on the thermal comfort of NZB rabbits in a precise and non-invasive way, which could assist the producer in decision-making.

THERMAL ENERGY FROM BIOGAS GENERATED FROM CATTLE MANURE AND SEWAGE SLUDGE

The major problems of public health, environmental impact, and energy dependence due to conventional fuels can be solved by using biogas from biodigesters. Therefore, the objective of this paper was to evaluate the energy potential of using biogas in the replacement of firewood and liquefied petroleum gas (LPG). For the biogas production, Indian model batch digesters were used in a batch supply system. Those were supplied with 100: 0, 75:25, 50:50, 25:75 and 0:100 sewage sludge: cattle manure (SS:CM). The calculation of the energy conversion was based on the accumulated biogas production, biogas production potential, the amount of waste produced by dairy cattle in a rural property and the equivalence of one cubic meter of gas with wood and LPG. In general, the adoption of biodigesters in rural properties to generate biogas for thermal energy consists of a viable and sustainable technology, regardless of the number of animals in the property. The use of sewage sludge antecipated biogas production, with the highest biogas production potential being 25:75 SS:CM. The financial savings obtained by the owner and /or community when installing a biodigester can be invested in the rural property. Therefore, it is concluded that there is a feasibility to replace firewood and LPG with biogas.

DEVELOPMENT OF SOFTWARE TO DETERMINE PRESSURES IN MULTICELULARSILOS WITH CONCENTRIC AND ECCENTRIC DISCHARGE

A computer program for determining the pressures, horizontal and friction, in prismatic slender silos, with square section, eccentric hopper and mass flow, international codes taken as basis were: AS 3774 (1996), DIN 1055-6 (2005) and BS EN 1991-4 (2006) and the theories proposed by Safarian (1969) and Walker (1966). The development application was made possible by the development of a computational algorithm in programming “Borland Delphi”. The program was carried out for five silos projects with truncated pyramid form hopper considering the following eccentricities: 25%, 30%, 35% and 43%, as well as a concentric model for comparison. The computer program allowed SILOEXCENTRIC easily and quickly be applied to slender prismatic geometry of silos with concentric and eccentric hoppers. The results demonstrated the efficiency of the computer program for the proposed objectives So SILOEXCENTRIC results in pressures that are stored in files in “Notepad” format that may be accessed are generated. Besides files, various data are presented in graphical form, facilitating the assessment of horizontal pressures and friction, which proved adequate to international standards, considering the limit states.