Information on the biomechanics of police dogs' tasks is important in understanding their work-related injuries and dysfunctions. This study aimed to develop and test a measurement tool for dogs' ...functional bite force and to report modified long attack-related kinetic and kinematic values. Twenty Finnish male police dogs, 7 German Shepherd Dogs (GSDs) and 13 Belgian Shepherd Dogs, Malinois (BSDMs), were included. Dogs accelerated 25 m and bit the helper's sleeve, fitted with three force sensors. Dogs were wearing a 3D accelerometer and were videotaped with a high-speed camera. The sleeve's reliability for measuring the dog's bite force was evaluated via intraclass correlation and Cronbach's alpha. Otherwise, a Mann-Whitney U-test was used, with significance set at
= 0.05. The sleeve's test-retest reliability was moderate to good (intraclass correlation of 0.75), and internal consistency was high (Cronbach's alpha 0.75). The GSDs' median bite force was 360.4 N (interquartile range (IQR) 628.6 N) and BSDMs' 247.0 N (IQR 289.8 N). Median acceleration maximum was 7.1 gravitational force equivalent (g) and median deceleration maximum was 11.6 g, with highest recorded forces being 9.2 g and 13.1 g, respectively. The measurement sleeve was a reliable tool for measuring functional bite force in GSDs and BSDMs. Forces related to bite, approach and impact in the two breeds were reported.
This paper describes a new and computationally efficient adaptive geometrical method for improving the resolution of electrocardiogram (ECG) S-peak detection. The target device is an ECG implant for ...dairy cows which provides limited calculation power. The method utilises only arithmetic operations and is adaptive to individual ECG curves and electrode installation effects. The method tracks the average heights of the sample points preceding and following the S-wave peak. Comparing these heights to the long-time average values provides an estimate of the offset of the peak sample from the actual peak moment. On average, the prediction of spline interpolation on the original 512 Hz turning point is 0.043 ms more accurate than our geometrical algorithm. Both methods result in less than a 0.7 ms difference from the original data. However, the proposed method is significantly more computationally efficient than cubic spline interpolation.
•Simple algorithm to improve the quality of cow ECG data using interpolation.•The algorithm is fast enough to run in real-time on a microcontroller•Useful for implantable devices to analyse beat-to-beat interval with high accuracy.
A single and uniform fertilizer application may lead to ineffective crop nutrient uptake and use. In order to enhance nutrient use efficiency the application should be adjusted according to the need ...of the cultivated crop. This task is challenging because weather is unknown and unpredictable over the upcoming growing season. One solution is site-specific fertilizer application in several separate events throughout the season. Such a precision fertilization method requires information on the current crop state (e.g. the availability of water and nutrients in the soil) and a crop growth model that aims to assess current crop growth and near future needs. A field experiment with varying radiation, precipitation and nutrient conditions was established to test our crop growth model performance. Spring wheat (Triticum aestivum L.) was grown using three fertilization rates with three precipitation and two radiation treatments within each fertilization treatment. The observed crop biomass accumulation in the highest fertilization treatment was considered as the highest possible in the prevailing conditions. The simulated (maximal) biomass accumulation was in agreement with the highest observed biomass yield. The results were found promising for further use of the model in crop growth evaluation during the growing season.
Passive dew collection could be a viable option as a source of irrigation water in arid areas. The plastic foil acting as a condensing surface plays a key role in the passive dew collection regime. A ...laboratory method for comparing various plastic foils for dew collection was prepared and tested. The focus was on creating a method for measuring the attributes affecting dew condensation and the flow of dew droplets on the measured surface. A low-density polyethylene foil designed for dew collection, white polyethylene plastic, black polyethylene plastic, and white polyvinyl chloride plastic were used as the test plastics. The laboratory dew yields were compared with model calculations. In addition, field trials were conducted in arid conditions in Maktau, Kenya, to compare with the laboratory measurement. Results from the hardware model tests were not reflected in the results obtained from the field conditions. The laboratory tests showed that the dew-harvesting quality of plastic foils is difficult to evaluate using the laboratory test rig. A more comprehensive evaluation regime requires tests performed in field conditions or further development of the test rig used here.
•A hardware model was constructed for testing plastic foils for dew collection.•Dew was harvested in controlled laboratory conditions and in arid field conditions.•No clear similarity was found between results in field and laboratory conditions.
•Soil and crop observations together with modeling were used to study the yield.•Soil PAWC did not significantly correlate with yield.•Soil Ksat correlated with yield only in few cases.•The simulated ...variation of the potential yield was lower than the observed.
The crop growth is highly dependent on growth conditions which vary from year to year making precision farming challenging. In the present paper was first investigated whether varying soil physical properties reflect the within-field yield variation of small grain cereals and how do the variations in weather conditions between growing seasons affect the within-field yield variation. Secondly, the potential biomass accumulation of the crop in existing soil and weather conditions was simulated. The simulated and experimentally based site-specific total biomasses were compared in order to find out whether the soil data explains the observed variations in yield.
Three experimental fields size of 3–4ha were established to examine the spatio-temporal yield variation during three years. The clay content of soils was high (> 46%) and soils were classified as Stagni-Vertic Cambisols. Correlations between soil water retention properties and crop yield were studied. Top and subsoil saturated (SWC), field capacity (FC) and permanent wilting point (PWP) water content, and saturated hydraulic conductivity of soil (Ksat), were determined from 19 to 24 places on each field once during the three years experimental period. During growing seasons, soil moisture content and leaf area index (LAI) were determined at same places biweekly, and yield was harvested. Spring barley (Hordeum vulgare) was grown on two fields, and spring wheat (Triticum aestivum, 2 years) and spring oilseed rape (Brassica napus L., one year) were grown on the third field.
The measured grain yields correlated with selected soil physical properties only in few cases. The observed spatial variation in the biomass was in most cases found to be higher than the simulated. Therefore, the above mentioned parameters were not enough to predict the yield correctly in case of high variations. There were other factors decreasing the observed yield e.g. lodging, cold summer, extremely high precipitation and slopes in field. According to our results it is evident that it is very difficult to predict site-specific biomass accumulation solely by soil properties in order, for instance, to fertilize in a site-specific manner. Therefore one needs to measure the crop during the growing season in order to simulate the biomass accumulation for precision farming purposes.
One of the methods with the most potential to reduce energy consumption in grain drying is heat recovery from the dryer exhaust air. A parallel plate heat exchanger to recover heat energy from the ...exhaust air of a recirculating batch grain dryer was examined by theoretical assessments as well as by measurements in a scaled-down research dryer and experimental heat exchanger. In addition to the heat transfer performance, the operability in dusty conditions was investigated. Finally, the optimization of the heat exchanger was introduced by the aid of the calculation models and practical measurement. The heat exchanger performed satisfactorily, providing an average energy saving of approximately 18%. A significant improvement in the performance could be achieved by increasing the air velocity. No severe dust accumulation was observed, and a heat exchanger of this type could provide remarkable energy saving possibilities in grain drying. Further tests are necessary to ensure the operability in long-term use.
A theoretical ammonia emission model was adapted to the conditions prevailing in a naturally ventilated dairy building. The relevant parameters including the mass transfer coefficient needed for the ...model were experimentally measured. Ammonia emissions from the dairy building were also calculated from directly measured ammonia concentrations and carbon dioxide mass balances from the dairy building. The results of the theoretical model for ammonia emission from manure were compared with the experimentally measured emissions inside the dairy building.
The absolute mean difference and standard error between ammonia emissions from the theoretical model and the experimental measurements was 0.013±0.005gm−3h−1. Parametric inaccuracy range in both emission estimation methods was 40%. A factor of ten difference was recorded between day and night ammonia emission rates. Ammonia emissions varied between 0.04 and 0.58gm−2h−1. The critical parameters that need to be considered in reducing ammonia emissions in dairy buildings according to the theoretical emission model were manure temperature, pH and total ammoniacal nitrogen of the manure.
Ammonia emissions were estimated at five microclimatic locations in a free stall dairy building using four different methods. Measurements were performed simultaneously with the different methods to ...enable comparison. In the first method, the rate of ammonia emission from manure was theoretically modeled utilizing Fick's law and boundary layer theory. In the second method, recirculation flux-chamber technique was used to model ammonia emission from manure. In the third and fourth methods, respectively, carbon dioxide and methane balances were employed to calculate ammonia emission. The mean ammonia emissions measured from the five locations using the different methods ranged from 0.10 to 0.15 g m⁻² h⁻¹. The percentage of variation of ammonia emission from the different location ranged between 8 and 52% for the different methods. Recorded ammonia emission rates in the dairy building were from 0.04 to 0.25 g m⁻² h⁻¹. The percentage of variation in ammonia, carbon dioxide, methane, and manure properties in the building was 50%. Two-way statistical analysis of variance showed that there were no significant differences (p > 0.63) between the four different methods or between the measurements obtained at the five locations (p > 0.90).
A simple and transparent analytical model for C3-crop biomass accumulation is introduced. The model is aimed to be used as a decision tool in precision farming. It is valid when growth is limited ...only by radiation or water and gives the optimal (maximum) biomass. It contains 8 fixed parameters, all with a clear basis in physics, chemistry and physiology. As a function of time, the growth is divided into two phases: exponential and linear. At an early stage of growth, the growth is exponential due to the expanding leaf area of the crop. At this stage, the model needs 6 parameters. The growth becomes linear when the leaf area is adequate to use all possible radiation. The model needs 2 parameters at this later stage. Water-limited growth needs an additional set of 4 parameters to describe phenomena of water related processes. When water is a limiting factor, the root-growth model becomes critical because the daily root growth determines the crop's growth directly. The model was tested first against field data at one point where all relevant inputs and parameters of the model were measured. Despite the simplicity of the model, there was a good agreement between simulated and measured values of biomass and leaf area. A scenario is described to show how the model may be used in practice and what kind of field data is needed. In on-line precision farming the key factor is the amount of radiation used by the crop, which can be measured adequately with two sensors, one above and one below the canopy.
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