Totally found 59 items.

  • [期刊] FORCES ON MONITORING CABLES DURING GRAIN BIN FILLING AND EMPTYING
    Monitoring the temperature of stored grain with permanent cables suspended from the bin roof is common practice in commercial grain storage and is sometimes used in on-farm grain storage bins. Knowledge of the forces imparted on the cables by flowing grain is required for proper design of cables, connection hardware, and bin roofs, but there is little data in the literature for full size bins. To determine forces on different cable sizes and configurations, five different cable designs were tested during filling and emptying of wheat and corn. Two concrete storage bins, 4.6-m diameter and 25-m maximum depth, were used with cables suspended from the center of the bin or suspended 0.6 m from the sidewall. The bottom ends of the cables were weighted, but were not fully restrained. Forces on the cables were monitored during filling and emptying of the bins. Forces during emptying usually exhibited slip-stick behavior. The greatest forces were during emptying, where forces were often double those during filling, with vertical forces up to 4.7 kN for the largest cable. Both peak and average forces for bin emptying were significantly larger than corresponding forces for bin filling. Results showed no effect of grain type (corn or wheat) while cable size had significant effects on peak and average force in most cases.
  • [期刊] DESIGN AND EXPERIMENTS OF COAXIAL CONTRA-ROTATING SUGARCANE BASE CUTTER WITH TIME-FREQUENCY CONTROL
    A laboratory-based cutting platform with speed control was developed to investigate the cutting mechanism for the support-cutting of sugarcane. A coaxial contra-rotating base cutter was designed to facilitate sugarcane support-cutting in a laboratory setting. The cutting platform, which consists of two discs with cutting blades, was driven by two variable-frequency electric motors. To manipulate the speed of each motor independently, a time frequency controller was designed to handle system nonlinearity and to maintain system stability subject to speed variation. To validate the cutter design, a series of idle running tests and cane-cutting tests were implemented using the laboratory-based cutting platform. The results indicated that the rotating speed of the two cutting discs could be adjusted smoothly. The controller capped the overshoot under 1% in the speed step response and kept the fluctuation of the speed difference of the two cutting discs at less than 2.5 rpm. Evaluating the cane quality of support-cutting against free-cutting showed that support-cutting decreased the stubble damage rate from 22.67% to as little as 6.67%. The results also suggested that the time-frequency-controlled cutting platform was feasible for subsequent investigation for a better understanding of sugarcane support-cutting, such as the variation of energy consumption or stubble damage rate with different rotating speed or different blade shape, which will provide constructive suggestions for the future base cutter design.
  • [期刊] LIFE-CYCLE ANALYSIS OF ADVANCED MANURE MANAGEMENT SYSTEMS FOR A WISCONSIN CONFINED ANIMAL FEEDING OPERATION (CAFO)
    Manure management is becoming an increasing burden for large dairy farms in Wisconsin and across the United States due to land application limitations for nutrients and hauling costs. One solution is to install advanced manure management systems, which remove large portions of water from the manure and treat it to a level sufficient for surface water discharge, livestock consumption, or irrigation. These systems can be divided into a pretreatment stage, which consists of solids removal, and a treatment stage, which generally consists of membranes. Not only does this approach reduce the quantity of material that is land applied, it can separate the nutrients into individual manure streams that can be more easily managed. However, there is still limited understanding regarding the costs and operation and maintenance requirements of these systems. To this end, a life-cycle analysis was completed for five commercially available advanced manure management systems based on how they would treat manure from a 3,500-cow dairy farm in Wisconsin, which was concerned only with the drawbacks of hauling and not application limitations. The evaluation included both an economic and non-economic analysis. The economic analysis consisted of a 20-year total present worth life-cycle cost analysis. The non-economic analysis consisted of a comparison of a set of non-economic factors that matched the management goals and strategies identified by the participating farm. Overall, all five systems evaluated addressed nutrient limitations and hauling costs. No treatment system had a payback less than 20 years at a hauling cost of $0.0040 L-1 ($0.015 gal(-1)). However, two systems had a payback period less than 20 years for a hauling cost of $0.0053 L-1 ($0.02 gal(-1)). Furthermore, if capital costs were ignored, the cost of recovered water was comparable to hauling costs for four of the alternatives. Still, there was high uncertainty in the estimated costs due to the low number of current installations of these systems on CAFOs. There was also a wide range of responses to the non-economic evaluation metrics, especially regarding performance, nutrient management techniques, chemical usage, and estimated regular operation and maintenance, which was again, likely due to the limited number of farm installations. Future work will verify actual costs and performance of these systems once implemented.
  • [期刊] EVALUATION OF THE PERFORMANCE OF A NEWLY DEVELOPED WIRELESS TEMPERATURE AND MOISTURE SENSOR FOR RICE UNDER VARIOUS LEVELS OF TEMPERATURE, MOISTURE CONTENT, AND DOCKAGE
    Monitoring on-farm, in-bin natural air drying process of rice is critical to achieve optimum milled rice quality, milling yields, and maximize profits to growers and processors. Engineering tools such as temperature/humidity cables with sensors for grain condition monitoring, and mobile applications have emerged to provide significant improvements in quality control and automation of the drying process. This research seeks to improve the performance of a recently developed, novel wireless probe for sensing temperature and moisture content of rice. The specific objective is to test the accuracy and precision of the measurements over a wide range of rice temperature (20 degrees C to 60 degrees C), moisture content (13% to 25% wet basis), and dockage levels (0 to 10% by weight). Wireless probes designed and built in collaboration with Deacon Technologies LLC were used in this study. The probes were calibrated against thermocouple readings for temperature measurements and standard oven method measurements for moisture content. Experiments were performed in triplicates using three different probes and three metal containers with rice samples to check the accuracy of the probes and to determine the variability amongst different probes. The probes were accurate due to the strong regressions found between the measured and true values of temperature and moisture content. The ANOVA analysis showed that there was no significant difference within different probes both for temperature (p = 0.17) and moisture content (p = 0.48) measurements. Calibration equations were developed to further reduce the variance in the probe measurements. Both for temperature and moisture content measurements, the calibration equation coefficients were statistically significant with positive slopes and small standard errors (less than 0.5). Thus, these probes could be handy for on-farm in-bin rice temperature and moisture monitoring; with the merits of portability, easy set-up and tear down, low initial and maintenance cost, and precise and accurate measurements.
  • [期刊] PHYSICAL AND THERMAL PROPERTIES OF CHIA, KANIWA, TRITICALE, AND FARRO SEEDS AS A FUNCTION OF MOISTURE CONTENT
    The knowledge of physical and thermal properties in cereals, grains, and oilseeds establishes an essential engineering tool for the design of equipment, storage structures, and processes. The physical properties and thermal properties for Chia, Kaniwa, Farro, and Triticale grains were investigated at three levels of moisture content: 10%, 15%, and 20% (d.b.). Physical properties included 1000-seed weight, dimensions, mean diameters, surface area, volume, sphericity, and aspect ratio. Results indicated 1000-seed weight increased linearly with moisture content from 2.0 to 3.5 g for chia, 2.5 to 4.0 g for kaniwa, 42.7 to 48.3 g for farro, and 51.0 to 53.7 g for triticale. The porosity for farro and triticale increased from 38.71% to 44.1%, 40.37% to 44.65%, respectively, as moisture increased. Angle of repose increased as moisture content increased, as did values of L, a*, and b* for all grains. Thermal properties of kaniwa, farro, and triticale showed high correlation to moisture content. A negative relationship was observed for the specific heat capacity and thermal conductivity, while the thermal diffusivity had a positive linear increase trend with moisture content. This study showed that physical and thermal properties varied from grain to grain as a function of moisture content, and these data will be useful for future application development.
  • [期刊] A REAL-TIME WEB TOOL FOR SAFE AERIAL APPLICATION TO AVOID OFF-TARGET MOVEMENT OF SPRAY INDUCED BY STABLE ATMOSPHERIC CONDITIONS IN THE MISSISSIPPI DELTA
    Susceptible crops can be injured far downwind if proper application spray procedure is not followed. Avoidance of stable atmospheric conditions while spraying is important to prevent surface temperature inversion-induced off-target drift of crop protection materials. Our previous studies consistently indicated high likelihood (>90%) of stable atmospheric conditions (unfavorable for spraying) primarily between the hours of 6:00 PM and 6:00 AM during clear conditions in the hot summer months at the Mississippi Delta. With the requirement of timely farm operations, a web application has been developed to provide real-time determination of atmospheric stability and to recommend whether aerial applications are appropriate for a particular location and time. An algorithm was developed to determine atmospheric conditions likely for occurrence of a temperature inversion. This algorithm was programmed using the Python programming language and uploaded to an internet-cloud application platform for publication via HTML. The algorithm calculates the potential of a temperature inversion every hour based on air temperature and wind speed data measured at weather stations deployed over the Mississippi Delta and surrounding areas. The web application is adapted for mobile terminals, such as smartphones and tablets, and can provide timely guidance for aerial applicators and producers to avoid crop damage and air quality issues long distances downwind.
  • [期刊] OPTIMUM FEATURE SUBSET FOR OPTIMIZING CROP YIELD PREDICTION USING FILTER AND WRAPPER APPROACHES
    In agriculture, crop yield prediction is critical. Crop yield depends on various features which can be categorized as geographical, climatic, and biological. Geographical features consist of cultivable land in hectares, canal length to cover the cultivable land, number of tanks and tube wells available for irrigation. Climatic features consist of rainfall, temperature, and radiation. Biological features consist of seeds, minerals, and nutrients. In total, 15 features were considered for this study to understand features impact on paddy crop yield for all seasons of each year. For selecting vital features, five filter and wrapper approaches were applied. For predicting accuracy of features selection algorithm, Multiple Linear Regression (MLR) model was used. The RMSE, MAE, R, and RRMSE metrics were used to evaluate the performance of feature selection algorithms. Data used for the analysis was drawn from secondary sources of state Agriculture Department, Government of Tamil Nadu, India, for over 30 years. Seventy-five percent of data was used for training and 25% was used for testing. Low computational time was also considered for the selection of best feature subset. Outcome of all feature selection algorithms have given similar results in the RMSE, RRMSE, R, and MAE values. The adjusted R(2 )value was used to find the optimum feature subset despite all the deviations. The evaluation of the dataset used in this work shows that total area of cultivation, number of tanks and open wells used for irrigation, length of canals used for irrigation, and average maximum temperature during the season of the crop are the best features for better crop yield prediction on the study area. The MLR gives 85% of model accuracy for the selected features with low computational time.
  • [期刊] MOISTURE-DEPENDENT PHYSICAL AND THERMAL PROPERTIES OF SERICEA LESPEDEZA SEEDS
    The bioactivity of Sericea lespedeza (SL) condensed tannins, including suppression of gastrointestinal nematodes, has contributed to a surge in interest of use of this plant in livestock production systems worldwide. Physical and thermal properties of SL seeds (AU Grazer (TM) and Serala cultivars) were determined as a function of moisture content for a moisture range from 8.57% to 26.53%, wet basis. The length, width, arithmetic mean diameter, geometric mean diameter, surface area, volume, and 1000 seed mass of both the seeds increased as the moisture content increased. Bulk density and unit density decreased as the moisture content increased. The sphericity of SL seeds decreased with increasing moisture content. Serala seeds were characterized by a higher aspect ratio than AU Grazer (TM). The angle of repose of SL seeds increased, while the compressibility index decreased in the moisture range. For color, the L* values of SL seeds decreased while the a* values increased with the increase in moisture content. A decrease in the b* values was insignificant. The thermal conductivity and specific heat of SL seeds decreased, whereas, thermal diffusivity increased as the moisture content of SL seeds increased. Serala seeds were characterized by higher values of thermal conductivity and volumetric specific heat than AU Grazer (TM).
  • [期刊] EVALUATION OF FILTER MEDIA OPTIONS FOR HIGH VOLUME PM2.5 SAMPLING
    Polytetrafluoroethylene (PTFE), glass fiber, and cellulose fiber filter media were evaluated under controlled conditions to determine their suitability for high volume PM2.5 sampling. Repeated mounting and unmounting events of new filters not exposed to ambient particulate matter were conducted in a laboratory environment and differences in the filter weight recorded. After the initial mounting and unmounting event, the filters exhibited weight changes of -2.24 mg, -0.61 mg, and 0.18 mg for cellulose, PTFE, and glass fiber filters, respectively. The standard deviation of replicated measurements after the first event was 1.76 (n = 9), 0.50 (n =10), and 0.31 (n =10) for cellulose, PTFE, and glass fiber filters, respectively. The combination of weight loss and standard deviation made the cellulose filter unsuitable for use in high volume PM2.5 samplers. However, improved performance over PTFE filters, suggests that glass fiber filters similar in specification to PTFE filters should be considered as acceptable substitutes in high volume PM2.5 sampling.
  • [期刊] DEMARCATION OF LEVEES IN IRRIGATED RICE FIELDS: LASER TECHNOLOGY VS. GNSS-RTK
    Levees are small land dikes made every rice-cultivation season that allow for flood irrigation in rice fields. Currently, levees are demarcated by utilizing a laser technology (LT) system. However, with current technological advances, the demarcation of levees with the Global Navigation Satellite System (GNSS) and real-time kinematics (RTK) correction has been highlighted in rice production systems in southern Brazil. The objective of this study was to compare the performance between LT and GNSS-RTK systems applied in the demarcation of levees that are used in flooded rice fields. To this end, an experimental area of approximately 27 ha located in Jaguarao, Rio Grande do Sul, Brazil, was used. From a digital elevation model, the area was subdivided into three subareas according to the mean slope: flat (0.16%), intermediate (0.36%), and gently undulated (1.3%). The total length of the levees for the three subareas was 8 km. The relative performances of both demarcation systems were evaluated by analyzing the vertical and horizontal behavior of the levees and the water layer spatial distribution. The results indicated that the demarcation of levees by GNSS-RTK systems is more accurate than that by the LT system, especially in flat areas. In these areas, the GNSS-RTK demarcation system permits a reduction in the total number of levees, as well as an increase in the vertical equidistance between levees and/or an increase in the height of the levee itself. The length of the levee is shorter than in a demarcation using the GNSS-RTK system.
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