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Harvesting renewable mechanical energy is envisioned as a promising and sustainable way for power generation. Many recent mechanical energy harvesters are able to produce instantaneous (pulsed) electricity with a high peak voltage of over 100 V. However, directly storing such irregular high‐voltage pulse electricity remains a great challenge. The use of extra power management components can boost storage efficiency but increase system complexity. Here utilizing the conducting polymer PEDOT:PSS, high‐rate metal‐free micro‐supercapacitor (MSC) arrays are successfully fabricated for direct high‐efficiency storage of high‐voltage pulse electricity. Within an area of 2.4 × 3.4 cm2 on various paper substrates, large‐scale MSC arrays (comprising up to 100 cells) can be printed to deliver a working voltage window of 160 V at an ultrahigh scan rate up to 30 V s−1. The ultrahigh rate capability enables the MSC arrays to quickly capture and efficiently store the high‐voltage (≈150 V) pulse electricity produced by a droplet‐based electricity generator at a high efficiency of 62%, significantly higher than that (<2%) of the batteries or capacitors demonstrated in the literature. Moreover, the compact and metal‐free features make these MSC arrays excellent candidates for sustainable high‐performance energy storage in self‐charging power systems. [ABSTRACT FROM AUTHOR]

At present, ginkgo leaves are still picked manually. A brush roller ginkgo leaf picker has been designed to improve harvesting efficiency and reduce losses caused by manual failure to pick leaves in time under large-scale planting areas. The ginkgo leaf picker is mainly composed of crawler chassis, gantry frame, brush roller picking parts, and collecting box. The kinematics of the brush roller are analyzed for the picking omission situation. An experimental platform for picking ginkgo biloba leaves was established. Three parameters, namely roller speed, moving speed, and roller inclination were selected for optimization. Then the maximum net harvest rate and the minimum damage rate were achieved. The orthogonal test showed that when the roller speed was 130 rev/min, the moving speed was 0.25 m/s, and the roller inclination was 32°, the picking effect was the best, the net harvest rate was 93.32%, the damage rate was 1.42%, and the damage degree of the trunks was slight. The experiment proved that the brush-roller ginkgo leaf picker has a good picking effect, which can provide a reference for the optimization design of ginkgo leaf harvesting machinery under the dwarf dense planting mode. [ABSTRACT FROM AUTHOR]

In order to improve the screening performance and cleaning effect of the jujube harvesting machinery cleaning device, a vibrating curved screen device was designed in this study. By analyzing the structure mechanism of the curved sieve body, it was obtained that the arc-shaped mesh hole spacing S was 15-25 mm and the curved mesh hole curvature U was 90°-150°. By exploring the movement state and stress of jujube and impurities on the curved sieve body, it was determined that the horizontal spacing L of the curved layer sieve was 30 mm and the vertical spacing H was 45-65 mm. Taking the vertical spacing H of the curved layer sieve, the curvature U of the curved mesh hole, and the spacing S of the curved mesh hole as the experimental factors, considering the screening efficiency α and the impurity content β of the jujube as the response values, the three-factor three-level quadratic regression orthogonal experiment was designed, establishing the regression mathematical model of each factor and response value, and the multiple target optimization algorithm of Design-expert software was used to optimize various factors. The results showed that the influence factors on the screening efficiency were in the descending order as: the arc screen spacing, the vertical spacing of the curved layer screen, and the curved screen hole curvature; The significant factors affecting the impurity content of jujube were in the descending order as: the arc screen spacing, the curved screen hole curvature, and the vertical spacing of the curved layer screen. The experimental results were verified by the optimized combination of parameters: when the vertical spacing H of the curved layer screen was 65 mm, the curved screen hole curvature U was 110°, and the arc screen spacing S was 23 mm, the average screening efficiency α in the test was 91.09%. The relative error between the experimental verification value and the theoretical optimization value was 1.36%, which was less than 5%. The impurity content of jujube β in the test was 1.02%. The relative error between the experimental verification value and the theoretical optimization value was 2.00%, which was also less than 5%. The test results can provide a reference for the research and optimization of the subsequent air-suction-type jujube harvester cleaning device. [ABSTRACT FROM AUTHOR]

Understanding the biomechanical properties of safflowers is essential for appropriately designing harvesting machinery and optimizing the harvesting process. Safflower is a flexible crop that lacks a basis for relevant simulation parameters, which causes difficulties in designing harvesting machinery. In this study, a calibration method for safflowers was proposed. First, a discrete element model was established by measuring the intrinsic parameters of a safflower, such as its geometric parameters, density, Poisson's ratio, and modulus of elasticity. Second, the contact and bonding parameters were calibrated using a combination of physical and simulation tests. In the contact parameter tests, the Hertz-Mindlin (no-slip) model was implemented for the stacking angle tests conducted regarding the safflower filament. A regular two-level factorial design was used to determine the important factors and perform the steepest climb test. Moreover, the Box-Behnken design was adopted to obtain the optimal contact parameters. In the bonding parameter tests, the Hertz-Mindlin model with bonding contact was applied for the safflower shear simulation tests; moreover, the optimum bonding parameters were obtained through the central composite design test. The results demonstrated that the relative errors between the simulated and measured stacking angles and maximum shear were 3.19% and 5.29%, respectively. As a result, the safflower simulation parameters were accurately calibrated, providing a reference for appropriately setting the simulation parameters and designing key mechanical components. [ABSTRACT FROM AUTHOR]

Building-integrated photovoltaics (BIPV) is an emerging technology in the solar energy field. It involves using luminescent solar concentrators to convert traditional windows into energy generators by utilizing light harvesting and conversion materials. This study investigates the application of machine learning (ML) to advance the fundamental understanding of optical material design. By leveraging accessible photoluminescent measurements, ML models estimate optical properties, streamlining the process of developing novel materials, offering a cost-effective and efficient alternative to traditional methods, and facilitating the selection of competitive materials. Regression and clustering methods were used to estimate the optical conversion efficiency and power conversion efficiency. The regression models achieved a Mean Absolute Error (MAE) of 10%, which demonstrates accuracy within a 10% range of possible values. Both regression and clustering models showed high agreement, with a minimal MAE of 7%, highlighting the efficacy of ML in predicting optical properties of luminescent materials for BIPV. [ABSTRACT FROM AUTHOR]

In response to the problems of low efficiency, high labor intensity, and low mechanization in manual tobacco harvesting, a comb-off tobacco picking device for southern hilly tobacco areas was designed following the agronomic requirements and the principle of manual picking of tobacco harvesting in southern China. The device was composed of the power chassis, picking mechanism, and storage mechanism. This study involved the theoretical analysis, structural design, and modeling of the key components, such as chassis structure, combing-type picking mechanism, and power synchronization mechanism. The results of the motion analysis and calculation of the picking process demonstrated that the adjustment range of the comb chain elevation angles was from 12.4° to 20.9°, the comb rod installation distance was 76.2 mm, and the synchronizing mechanism transmission ratio was 3:10. One-factor test and three-factor three-level orthogonal test was performed with the forward speed of the chassis, the distance between the picking device baffles and the elevation angle of the chain with the combing bar as test factors, and the rate of broken and missed tobacco picking as evaluation indicators. It was revealed that the optimal combination of the forward speed of the chassis, the distance between the baffles, and the chain elevation angle were 1.5 km/h, 75 mm, and 12.4°, respectively. Moreover, verification tests suggested that the breakage rate of tobacco leaves was 9.99%, and the probability of missed tobacco picking was 7.31%, both of which satisfy the agriculture requirements and the operational requirements in the agricultural machinery certification syllabus. [ABSTRACT FROM AUTHOR]

In this study, the discrete element software EDEM was applied to establish a simulation model of non-uniform-sized particle units for Broussonetia papyrifera stalks, which aimed to address the low utilization rate of existing Broussonetia papyrifera harvesting machinery, the significant variation between the simulated model of Broussonetia papyrifera stalks and their actual appearance, as well as the absence of contact parameter calibration. Through a combination of the free-fall collision method, inclined plane sliding method, and inclined plane rolling method, numerical simulation was conducted to analyze the pattern of variations in contact parameters between Broussonetia papyrifera stalks and the steel material of the machinery. Accordingly, these parameters were calibrated. The results showed that the coefficient of restitution between Broussonetia papyrifera stalks and steel materials was 0.321, the static friction factor was 0.589, and the rolling friction factor was 0.078. With the parameters of contact between Broussonetia papyrifera stalks as variables and the experimentally measured pile angle as the objective of optimization, the steepest ascent experiment and the three-factor five-level rotation combination experiment were conducted. In this way, a second-order response model was constructed to analyze the relationship between the contact parameters and the pile angle. Through the optimization analysis of experimental data, it was determined that the coefficient of restitution between Broussonetia papyrifera stalks was 0.21, the static friction factor was 0.24, and the rolling friction factor was 0.03. Furthermore, the calibration results were validated through experimentation to show that the relative error between the obtained pile angle under the context of optimal parameter combination and the actual one was 4.11%. In addition, the relative error of mass flow rate in spiral transport was within a reasonable range, this study lays a foundation both theoretically and statistically for the simulation of contact parameters for Broussonetia papyrifera stalk harvesting processing, mechanical harvesting, and so on. [ABSTRACT FROM AUTHOR]

The fruit weight is an important guideline for breeders and farmers to increase marketable productions, although conventionally it requires destructive measurements. The combination of image-based phenotyping (IBP) approaches with multivariate analysis has the potential to further improve the line selection based on economical trait, like fruit weight. Therefore, this study aimed to evaluate the potential of image-derived phenotypic traits as proxies for individual fruits weight estimation using multivariate analysis. To this end, an IBP experimentation was carried out on five populations of low-land tomato. Specifically, the Mawar (M; 10 plants), Karina (K; 10 plants), and F2 generation cross (100 lines) samples were used to extract training data for the proposed estimation model, while data derived from M/K//K backcross population (35 lines) and F5 population (50 lines) plants were used for destructive and non-destructive validation, respectively. Several phenotypic traits were extracted from each imaged tomato fruit, including the slice and whole fruit area (FA), round (FR), width (FW), height (FH), and red (RI), green (GI) and blue index (BI), and used as inputs of a genetic- and multivariate-based method for non-destructively predicting its fresh weight (FFW). Based on this research, the whole FA has the greatest potential in predicting tomato FFW regardless to the analyzed cultivar. The relevant model exhibited high power in predicting FFW, as explained by R2-adjusted, R2-deviation and RMSE statistics obtained for calibration (81.30%, 0.20%, 3.14 g, respectively), destructive (69.80%, 0.90%, 4.46 g, respectively) and non-destructive validation (80.20%, 0.50%, 2.12 g, respectively). These results suggest the potential applicability of the proposed IBP approach in guiding field robots or machines for precision harvesting based on non-destructive estimations of fruit weight from image-derived area, thereby enhancing agricultural practices in lowland tomato cultivation. [ABSTRACT FROM AUTHOR]

Energy harvesting, as a sustainable power source for implantable medical devices within the human body, is an intriguing area of research. The utilization of biochemical and biomechanical energy derived from the body offers a promising sustainable energy source. However, obtaining high power density in vivo is a challenge. Herein, energy harvesting is demonstrated using hybrid energy harvesters that simultaneously use mechanical energy from stretching and chemical energy from glucose. The hybrid energy harvesters operate as both biofuel cells (BFC) and mechano‐electrochemical energy harvesters (MEEH) within a single electrochemical cell. As a result, the hybrid energy harvesters offer a maximum power density of 17.8 W kg−1 and an average power density of 15.1 W kg−1. These values increase by 14.5% in maximum power density and 16.8% in average power density, compared to the sum of the power density obtained by mechanical stretching and glucose oxidation individually. Based on their improved performance and compact size, owing to the synergistic effect of the two electrochemical harvesting methods, these hybrid harvesters have the potential to be applied to implantable power sources. [ABSTRACT FROM AUTHOR]

Energy harvesting, as a sustainable power source for implantable medical devices within the human body, is an intriguing area of research. The utilization of biochemical and biomechanical energy derived from the body offers a promising sustainable energy source. However, obtaining high power density in vivo is a challenge. Herein, energy harvesting is demonstrated using hybrid energy harvesters that simultaneously use mechanical energy from stretching and chemical energy from glucose. The hybrid energy harvesters operate as both biofuel cells (BFC) and mechano‐electrochemical energy harvesters (MEEH) within a single electrochemical cell. As a result, the hybrid energy harvesters offer a maximum power density of 17.8 W kg−1 and an average power density of 15.1 W kg−1. These values increase by 14.5% in maximum power density and 16.8% in average power density, compared to the sum of the power density obtained by mechanical stretching and glucose oxidation individually. Based on their improved performance and compact size, owing to the synergistic effect of the two electrochemical harvesting methods, these hybrid harvesters have the potential to be applied to implantable power sources. [ABSTRACT FROM AUTHOR]

A precise assessment of tomato ripeness is crucial in the harvesting and marketing procedures. Chlorophyll fluorescence is being relied on as a harmless approach for tracking the maturity of tomatoes in postharvest research. In this study, mathematical model is proposed based on measuring the intensity of fast chlorophyll fluorescence of tomatoes depending on their degree of maturity. In the experimental study, four stages of tomato ripening (green, turning, pink, and red) for three varieties ('Alkazar', 'Lezginka', and 'Rosanchik') were used. The Fluorescence Intensity (FI) data over time were represented using a third-degree polynomial function and finding its first derivative curve. The FI parameter was obtained as the fluorescence level at the first inflection point on the fluorescence induction curve (at time tI on the first derivative curve). According to the obtained mathematical models, the optimal time for monitoring the degree of ripeness of tomatoes was tI = 129 ± 4 ms. According to the results of experimental studies, there is a general trend, regardless of the variety used, that the FI decreases with tomato maturity. The FI may assist in sorting and grading processes for fresh vegetables and fruits. It can also be used as a system that can be integrated into harvest and post-harvest machinery for agricultural products. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have been considered a promising energy harvester. However, the wear-induced limited lifetime of the surface structure on fluoropolymeric contact layers of the TENG has been a critical issue in its commercialization because surface structures on soft engineering materials play a key role in enhancing the generation of electricity in TENGs. After the surface structure on the polymeric contact layer is worn out, the layer is required to be replaced with a new one with intact surface structures to reenhance the degraded output performance of the TENG. Herein, injection molding-assisted mass production is applied to manufacture micro/nanoscale surface-structured perfluoroalkoxy alkane (PFA) contact layers, which exhibit easily replaceable but fully recyclable characteristics. The optimized production time is shorter than 1 min, and the unit cost under $1 of manufacturing surface-structured PFA contact layers is achieved. TENG with the fabricated PFA contact layer can generate over 620 V of voltage and up to 12.4 mW of power from solid-solid contact and separation when the contact area is 5 cm × 5 cm and the contact frequency is 10 Hz. The manufactured PFA contact layer can be facilely replaced with a new one before the end of its lifetime to maintain the electrical output of the TENG, and the postused one can be fully recycled via reprocessing as the material for injection molding. Consequently, a tile-floor-based TENG is proposed as a proof-of-concept demonstration to show environmentally friendly and closed-loop production of TENGs. [ABSTRACT FROM AUTHOR]

The field harvesting process of harvesting machinery is often affected by high workload and environmental factors that can impede/delay manual rowing, thereby leading to lower efficiency and quality in the residual film collector. To address this challenge, an automatic rowing control system using the 4mz-220d self-propelled residual film collector as the experimental carrier was proposed in this study. Cotton stalks in the ridges were chosen as the research object, and a comprehensive application of key technologies, machinery, and electronic control was used, thereby incorporating a pure tracking model as the path-tracking control method. To achieve the automatic rowing function during the field traveling process, the fuzzy control principle was implemented to adjust the forward distance within the pure tracking model dynamically, and the expected steering angle of the steering wheel was determined based on the kinematic model of the recovery machine. The MATLAB/Simulink software was utilized to simulate and analyze the proposed model, thus achieving significant improvements in the automation level of the residual film collector. The field harvesting tests showed that the average deviation of the manual rowing was 0.144 m, while the average deviation of the automatic rowing was 0.066 m. Moreover, the average lateral deviation of the automatic rowing was reduced by 0.078 m with a probability of deviation within 0.1 m of 95.71%. The research study demonstrated that the designed automatic rowing system exhibited high stability and robustness, thereby meeting the requirements of the autonomous rowing operations of residual film collectors. The results of this study can serve as a reference for future research on autonomous navigation technology in agriculture. [ABSTRACT FROM AUTHOR]

Mechanical damage during the potato harvesting process contributes to 70% of the total damage in the overall potato production system. To optimise the design of the soil-potato sorting system in potato harvesting machines, it is informative to study the dynamics and kinematics of the soil-potato sorting processes using the discrete element method (DEM). In this study, the equivalent Young's modulus of two potato cultivars, Dutch15 and Gansu, was determined through quasi-static loading experiments. Subsequently, a contact force model was developed using impact information (force, displacement, and displacement rate) obtained from a pendulum device to accurately represent the viscoelastic–plastic behaviour of potatoes. Finally, a comparison was conducted to validate the performance of the newly developed model. The results indicate that the newly developed model (R 2 = 0.91 ± 0.06) outperforms the Kuwabara and Kono model (KK-model) (R 2 = 0.49 ± 0.09) and the Yigit–Cristoforou model (YC-model) (R 2 = 0.28 ± 0.13) in terms of fitting force-deformation profiles. The fitted novel model provides valuable insights into the internal force variations within potatoes during collisions. • A model was developed to illustrate the viscoelastic–plastic behaviour of potatoes. • The equivalent dissipation parameters for the developed model were determined. • A comparison was conducted to validate the performance of the new model. • The developed model has a good ability on force-deformation fitting (R 2 = 0.91). [ABSTRACT FROM AUTHOR]

Real-time condition monitoring of various types of machinery using sensor technology has gained significant importance in recent years. However, relying on batteries to power these sensors proves to be sub-optimal, as it necessitates regular charging or replacement. To address this, harvesting waste energy from ambient sources emerges as a more efficient alternative. Everyday applications like vehicle wheels, fans, and turbines present ambient sources of waste rotational energy. In this study, we propose a novel rotational energy harvester design that converts rotational energy into linear energy. This linear energy impacts a piezoelectric disk, generating an electric potential. Through simulations, the expected electric potential at varying frequencies was evaluated. Subsequently, experimental tests were conducted by connecting the harvester to a rectifier for AC-to-DC signal conversion and an oscilloscope for voltage measurement. A DC motor replicated the rotational motion at the frequencies from the simulation, and the power output was measured. Using the power transfer theorem, simulation and experimental power outputs were calculated, resulting in values of 188, 513, and 1293 μW and 88.89, 336, and 923 μW, respectively. These results reveal that the designed harvester is competitive with those of existing rotational energy harvester designs, demonstrating the promising potential of this novel harvester. [ABSTRACT FROM AUTHOR]

In Vietnam, post-harvest losses of fruits and vegetables are very high. According to analysis reports, Vietnam must invest more in harvesting and post-harvest technologies to enhance the global competitiveness of agricultural products, including fruits and vegetables. Fruit harvesting machines are an effective solution to enhance the quality of agricultural products, including fruits and vegetables. The gripper can be considered the most important component of a harvesting machine when it comes to horticulture products, since it acts as interface between the robotic system and product. To pick up fruits, which frequently have complex shapes and poor mechanical properties, a gripper must be designed carefully. In addition to being able to pick the produce, it is crucial that a gripper does not damage the fruit during harvest. The weak force may cause the gripper to be unable to pick the fruit. If excessive force is applied or improper picking technique is used, the grippers could damage fruits. However, Vietnam has not widely adopted the use of automatic machine in agriculture. This is due to the uniqueness of fruits in each region; for example, fruits in Vietnam have their own shape and mechanical properties. Therefore, it is occasionally inappropriate to utilize harvesters that have already been imported. This paper shows the development and fabrication of a gripper for common Vietnam fruit grasping. A new prototype has been fabricated by 3D printing method and tested in the laboratory. The prototype of a gripper has been subjected to simulation and experimental testing with real fruits to verify that the proposed model is capable of meeting all objectives' requirements. The proposed gripper was straightforward and efficient. The developed device exhibited dependability and stability and is suitable for farmers who require independent harvesting. In addition, the designed gripper can be produced at a lower cost than comparable machines developed by other commercial products. [ABSTRACT FROM AUTHOR]

At present, the research on the physical composition and properties of pineapple plants is scarce, and the uncertainty of fruit picking method is the key bottleneck factor hindering the research and development of pineapple harvesting machinery. Based on the statistics of survey data from many places, this paper analyzes the fruit-stem fracture mechanism and the theoretical conditions for optimal separation through structural modeling, mechanical behavior analysis and function judgment. On this basis, the "pineapple plant fixation bench" and "fruit-stem bending separation torque test equipment" were developed, and large-size, small-size tests and random optimization tests were carried out successively. The test results showed that the larger of the stem-stalk fixation distance, the more torque and fracture starting angle required for fruit fracture would increase, and the change range was small when the stem-stalk fixation distance was within 50 mm, and the probability of brittle fracture and complete separation was very high. When the space between the fracture section and the fruit-stem connecting point is about 5mm, the range of bending moment value required for the fruit-stem fracture is 1.88 to 2.77 N·m, the range of fracture starting angle is 12.2° to 18.1°, and the angular travel range during the separation process is 82.9° to 87.5°. When the stem-stalk fixation distance is about 15 mm, it is the best fruit-stem separation condition and the breaking torque measured in the verification test is about 2.76 N·m. The fracture starting angle is about 13.8°, the maximum prediction error is 13.1%, and the elastic modulus near the fruit-stem joint ranges from 16.1 to 23.9 MPa. This conclusion can provide an important design basis for the research and development of pineapple field picking robot and harvesting equipment. [ABSTRACT FROM AUTHOR]

Fully mechanized maize production has been trending in China, and using agricultural machinery to harvest maize grains is the focus of the transformation of maize production methods. Grain moisture content is the main factor affecting mechanical kernel harvesting, which is mainly affected by the agronomic characteristics of maize, ecological meteorological factors at the late growth stage, cultivation and management practice and other factors. Northeast China (NEC) is one of the main maize production regions and is the most sensitive regions to climate change in China. Clarifying the climate suitability and suitable zones for mechanical maize kernel harvesting in NEC under future climate conditions can provide scientific basis for improving the mechanization level of maize production and realizing the fully mechanized maize production in the future. In this study, based on the predicted climate data of 2021−2060 under two greenhouse gas concentration scenarios of RCP4.5 and RCP8.5 (the radiation forcing levels will reach 4.5W·m−2 and 8.5W·m−2 by 2100, which representing medium and high emission scenario, respectively) and the growth period data of spring maize, the northern boundaries of climate suitable zones for mechanical kernel harvesting of currently widely planted 29 middle-late spring maize varieties were determined using the kernel moisture content prediction models, and further the multi-variety based climate suitable zones were analyzed for the future 40 years. The results showed that climate very suitable, suitable, moderately suitable and marginally suitable zones for mechanical kernel harvesting will extend from southwest to northeast in NEC. And among different varieties, the northern boundaries of climate suitable zones fluctuate from the southwest to the southeastern mountainous areas of Jilin province (Changbai, Donggang and Songjiang areas) and the northern high latitude areas of Heilongjiang province. Under RCP4.5 (RCP8.5) climate scenario, the very suitable zones for 50% and 80% of middle-late maturing spring maize varieties located in the southern part of Liaoning province (the western and southern parts of Liaoning province). The northernmost can reach 42.0°N and 41.0°N (42.8°N and 41.9°N) latitude, and the easternmost can reach 123.4°E and 123.3°E (124.5°E and 123.3°E) longitude, respectively. The areas account for 5.9% and 1.8% (11.2% and 5.9%) of the potential growing area of spring maize in NEC, respectively. Suitable zones located in the northern and central parts of Liaoning province (the northern part of Liaoning province and southwestern part of Jilin province), with the northernmost reaching 43.0°N and 42.7°N (44.8°N and 42.9°N) latitude, the easternmost reaching 124.7°E and 124.4°E (124.7°E and 124.5°E) longitude, and the areas accounting for 8.3% and 8.9% (4.7% and 6.6%) of potential growing area of spring maize, respectively. In the future 40 years, compared with the RCP4.5 climate scenario, the middle-late maturing varieties of spring maize under RCP8.5 climate scenario have stronger climatic suitability for mechanical kernel harvesting, but the climate very suitable and suitable zones under the two climate scenarios are both small. The climate suitable zones for mechanical kernel harvesting will differ greatly between varieties, so varieties with short growth periods and fast dehydration rates which are suitable for mechanical kernel harvesting should be selected to improve the quality and efficiency of mechanical kernel harvesting in the future. [ABSTRACT FROM AUTHOR]

An important breeding issue in buckwheat is to increase its resistance to lodging, which can result in the loss of yield and quality of buckwheat foods. We developed the semidwarf buckwheat 'Kyukei 50', which has a short plant height and a strong lodging resistance. The internode length of 'Kyukei 50' was shorter than that of the summer‐sown standard variety 'HITACHIAKISOBA'. Progeny analysis revealed that the semidwarf trait was dominated by at least one recessive gene. Compared with 'HITACHIAKISOBA', in 'Kyukei 50', the time of maturation was earlier, and the pre‐harvest sprouting resistance was the same, indicating that 'Kyukei 50' is suitable for sowing in both spring and summer. 'Kyukei 50' exhibits the 'green flower type' shattering resistance trait and, therefore, has a thick pedicel; breaking tensile strength is approximately two‐fold stronger than that of 'HITACHIAKISOBA'. The yield of 'Kyukei 50' is the same as that of 'HITACHIAKISOBA'. In addition, the lowest seed height of 'Kyukei 50' was >17 cm. These results indicate that the 'Kyukei 50' is a promising breeding line for lodging resistance and loss of harvesting machinery. [ABSTRACT FROM AUTHOR]

The present manuscript focuses on the thermal and mechanical energy harvesting through flexible PVDF/PLZT (Polyvinylidene Fluoride/ Lanthanum doped lead zirconium titanate) composite films prepared using solution-cast technique. The effect of Lanthanum doped lead zirconium titanate (PLZT) ceramic content in the composite was studied in terms of its structural, morphological and dielectric properties. The pyroelectric coefficient, figure of merit and piezoelectric voltage were determined for pure PVDF and PVDF/PLZT composite films. With increasing PLZT concentration in PVDF from 0 to 50%, the pyroelectric coefficient values were found to vary from 0.5 × 10–4 Cm−2 K−1 to 18 × 10–4 Cm−2 K−1 respectively. The maximum piezoelectric voltage of 1.5 V was achieved for PVDF/PLZT (50%) flexible composite films. The obtained pyroelectric coefficient and piezoelectric voltage for the PVDF/PLZT (50%) composite film revealed its importance in terms of performance for thermal and mechanical energy harvesting. [ABSTRACT FROM AUTHOR]

Stalk lodging is prone to occur during the harvesting of green forage maize due to the header and root anchorage, resulting in loss of harvest. In particular, the fallen stalk wraps around the header, causing a blockage and increasing the energy cost. To address this problem, the deflection model was analyzed and established and a novel method to explore the field bend characteristics of green forage maize was proposed. The effects of stalk diameter, bending angle, and cutting height on bending stress and Young's modulus were explored by using the method of in-situ measurement. Additionally, the bending deflection, axial displacement and measuring point displacement were obtained. Experimental results indicate that the stalk diameter and bending angle have a significant influence on bending stress. The bending stress has a positive correlation with bending angle and cutting height, while there is a negative correlation with stalk diameter. On the other hand, the bending angle, stalk diameter, and cutting height are closely related to the Young's modulus. The mean values of the Young's modulus decrease as a quadratic function with the increasing diameter and bending angle, while the cutting height has the opposite effect on it. Besides, the average values of bending deflection, axial displacement, and measuring point displacement exhibit an increasing trend when the bending angle and cutting height increase. This study results can provide a reference for studying the failure mechanism of green forage maize stalk harvesting, and the design of green forage maize harvesting machinery. [ABSTRACT FROM AUTHOR]

In this study, we propose an analytical approach based on the modified differential transform method to investigate the dynamic behavior of a plucking energy harvester. The harvester consists of a piezoelectric cantilever oscillator and a rotating plectrum. The analytical approach provides a closed-form solution that helps determine the starting and ending points of the contact phase between the piezoelectric cantilever and the plectrum. This analytical approach is valuable for simulating complex dynamic interferences in multiple or periodic plucking processes. To evaluate the effects of plucking speed and overlap length of the plectrum on single and periodic plucking, a series of simulations were carried out. The output voltage of the piezoelectric energy harvester increases as the overlap length of the plectrum increases. On the other hand, increasing the plucking speed tends to amplify the magnitude of the contact force while reducing the duration of the contact phase. Therefore, it is crucial to optimize the plucking speed to achieve the maximum linear impulse. For periodic plucking, successful synchronization between the motions of the piezoelectric energy harvester and the rotating plectrum must occur within a limited contact zone. Otherwise, dynamic interferences often cause the plectrum to fail to pluck the energy harvester exactly within the contact zone. Additionally, reducing the plucking speed of the plectrum and increasing the overlap length would be more advantageous for successful periodic-plucking energy harvesting. [ABSTRACT FROM AUTHOR]

Walnut mechanical properties are an appropriate criterion for designing and adjusting the various parts of harvesting machines that are in contact with walnut. In this research, the aim is to find the effect of ultrasound factors on walnut mechanical properties to reduce walnut rupture force and energy. Walnuts were treated with three ultrasound time duration (5, 10, and 15 min) and three ultrasound bath temperatures (20, 35, and 50ºC). After the walnuts were treated by ultrasound factors, wet and dried walnut samples were loaded at three loading speeds (0.5, 1.5, 2.5 mm/s) along width and length direction for determination of mechanical properties. Regarding the ANOVA results, the ultrasound time factor had the most effect on the rupture force, energy, and toughness. Results showed walnut ultrasound-treated samples had minimum rupture force and energy. Also, rupture force, required energy, and toughness decreased with increasing ultrasound bath temperature and the ultrasound time duration. The minimum walnut rupture force was obtained at 62.7 N in 25 min ultrasound time duration, 50ºC bath temperature, 1.5 mm/s loading speed, and width loading direction for wet walnut sample. [ABSTRACT FROM AUTHOR]

Rice is a crop that contributes significantly both to food security and to ensure adequate income levels for farmers. This motivates efforts in many countries to disseminate techniques that increase production while being environmentally friendly and affordable to small farmers. The objective of this article is to study the process of adoption of innovations in rice cultivation in Ecuador. Four practices that increase yields and improve natural resource management have been selected: land leveling, certified seed, widely spaced transplanting, and the use of harvesting machinery. The factors that most influence their adoption are studied for each of them: human and social capital, and institutional support for agriculture. In addition, the interrelations of some practices with others are analyzed. Multivariate probit estimation shows that education is the main factor that increases the probability of adopting these practices. And with unequal incidence are associationism, access to credit and insurance. The complementarities found between different practices point to the convenience of promoting them jointly to take advantage of their synergies. [ABSTRACT FROM AUTHOR]

In response to the problem of high stubble damage rate during sugarcane harvesting, the interaction between sugarcane stalks and basecutter was analyzed, and a sugarcane stubble basecutting device was designed based on the combination of "sliding cutting and shearing cutting" to improve the cutting quality. The principle of unsupported cutting of traditional disc basecutters and supported cutting of sliding shear combination basecutters was analyzed. The result was shown that supported cutting could effectively reduce the bending resistance and inertia force of stems, thus preventing significant deformation of stems to a certain extent, effectively ensuring the cutting quality of stems, and sliding cutting can effectively reduce cutting resistance. The parameters of the key components of the basecutter were determined by establishing the force model of the stem. The sliding cutting operation is carried out using an equal sliding angle blade curve, and the sliding cutting angles and blade bevel angles were 40 ° and 45 °, respectively. The statics and modal analysis of the basecutter were conducted to prevent insufficient tool strength and resonance between the basecutter and the motor during shearing using ANSYS/Workbench. An optimal combination was achieved to fully meet the performance requirements, in terms of structural strength, where the yield strength of the basecutter was 450-650 MPa, while the maximum stress on the basecutter was 102 MPa, and the maximum displacement was 4.94×10-5m. The excitation frequencies of the cutting and the feeding motors were 0- 6.667 and 0-11.667 Hz, respectively. The modal analysis results show that the excitation frequencies of the two motors were much smaller than the first-order natural frequency of the basecutter (60.89 Hz). Therefore, the smooth operation of indoor experiments was obtained without any resonance. A basecutting test bench was built with adjustable cutting disc rotational speed, feeding speed, and cutting angle. The results of the single-factor test showed that when the cutting angle, cutting disc rotational speed, and feeding speed were 10-15 °, 140-220 r/min, and 1.1-1.7 m/s, respectively, the comprehensive evaluation value y was small and the cutting quality was better. The results of orthogonal experiment analysis of variance showed that each factor had a significant impact on the comprehensive evaluation value y. The range analysis of orthogonal experiments shows that the optimal experimental level is the cutting angle was 15 °, the cutting disc rotational speed was 180r/min, and the feeding speed is 1.4m/s. After experimental verification, the comprehensive evaluation values y were 0.256 and 0.298 at this time, indicated the cutting quality was better. Referring to the DG/T 117-2021 sugarcane harvesting machinery test method, the sugarcane stubble damage rate was inspected. The shear qualification rate was as high as 90.4%, and the stubble damage rate was reduced to below 10%. The operation quality of the sliding shear combined sugarcane basecutter met industry requirements. [ABSTRACT FROM AUTHOR]

Seabuckthorn is one of the most important ecological cash crops in modern agriculture. The existing seabuckthorn forests in China are accounted for more than 90% of the world's total crop area. However, the current manual harvesting cannot fully meet the large-scale production in recent years, because the fruits can be clustered in the thorny branches. It is also a high demand for seabuckthorn harvesting machinery rather than manual ones. In this study, the movable double blades cutting device was developed to investigate the effect of the cutting parameters on the harvesting performance of seabuckthorn branches. The optimal combination of cutting parameters was also achieved after the experiment and simulation. The sample branches were four years old, 300 mm in length, with a moisture content of 43.13% to 53.83% (average 47%). The test instruments included the self-developed double blades cutting test device, a video recorder, and a digital camera. The cutting test device consisted of three units (the cutting, branch feeding, and control unit). The single factor and orthogonal tests were also carried out to verify the simulation. The experimental factors in the single factor tests were the average cutting speed (0.4~0.8 m/s), sliding cutting angle of the blade (7.5°, 15°, and 22.5°), blade height (35, and 70 mm), and the number of the movable blade (single, double), where the average cutting speed was set at 5 levels. A regression model was established for the orthogonal tests. The Box-Behnken method was designed with a three-factor, three-level test scheme. The average cutting speed (0.4-0.6 m/s), branch feeding speed (0.5-0.7 m/s), and sliding cutting angle of the blade (7.5°, 15°, and 22.5°) were selected as the experimental factors, whereas, the peak cutting force per unit diameter and cutting power consumption per unit area were set as the evaluation indexes. Response surface analysis was used to optimize the regression model. The experimental results show that the evaluation indexes decreased with the increase in average cutting speed, sliding cutting angle of blade, and blade height. The values of these indexes were smaller for the double movable blades, compared with the single ones. The average cutting speed and sliding cutting angle of blade presented the highly significant effects on the evaluation indexes ( P<0.01), while the branch feeding speed shared a non-significant effect on the evaluation indexes ( P>0.05). The key factor for the quality of the cutting section was the average cutting speed when the branch feeding speed was determined. The optimal combination of cutting parameters for the double movable blades was: the average cutting speed of 0.45 m/s, the branch feeding speed of 0.64 m/s, and the sliding cutting angle of 9.4°. Specifically, the peak force per unit diameter was 53.33 N/mm, and the cutting power consumption per unit area was 69.87 N/mm² under the combination. Three groups of verification tests were carried out for the experimental optimization. The relative error of the regression model was less than 5%, indicating the reliable optimization of cutting parameters. Therefore, the optimized conditions were reasonable in this case. The optimized parameters (such as the average cutting speed, branch feeding speed, and sliding cutting angle of the blade) can be expected to effectively reduce the peak force per unit diameter for the cutting power consumption saving per unit area. The finding can provide the data support for the subsequent development of seabuckthorn harvesting equipment. [ABSTRACT FROM AUTHOR]

Presently, there is a dearth of professional climbers to carry out coconut harvesting because it involves considerable risk posed by the tree height and uneven trunk surface. Numerous coconut-tree-climbing devices have been developed to overcome this issue, but human effort is still required. Hence, it is imperative to develop a wheel-driven mechanism in the structure with a continuous motion to harvest coconuts. By featuring an anti-falling capability, the climber can be stable in static and dynamic conditions. This feature can be achieved by attaching springs in the supporting frame during vertical climbing on the trunk surface. This paper presents a 3D modeling and the static and dynamic analysis of a climbing machine. The climbing field trials of the climbing model were carried out on a coconut tree trunk, and the best climbing rate that was achieved was 0.3 m in 1.6 seconds. Control of the climber maneuverability was tested with an embedded processor board. The maturity identification of coconuts in a complex background was successfully achieved with a detection score of 99% on real-time images by using deep learning techniques. This study can be extended to identify the cutting point of the coconut bunches for harvesting. [ABSTRACT FROM AUTHOR]

In view of the complex agronomic technology of highland barley production and the lack of special machinery for harvesting and bundling highland barley, the harvesting of highland barley is basically done manually. There is a seriously reduced degree of mechanization of highland barley harvesting. Therefore, this paper designs a self-propelled highland barley harvesting and bundling machine, which realizes a single operation process to complete mechanized complex operations such as harvesting, bundling and laying highland barley. By designing the highland barley harvesting method and cutting platform, the height of the cutting platform can be adjusted stepless, and the highland barley bundle knotter is designed to realize the regulation and control of the baling diameter of the highland barley. According to the design of the rope feeding mechanism, the gathering mechanism and the baling mechanism, the main parameters of the baling device are determined. The stubble cutting height of the machine is 325 mm, the average diameter of the highland barley bundles is 195 mm, the average weight per bundle is 5.08 kg, bale formation rate is 97.8%, the qualification rate of the straw bundle reaches 95.6%, drop resistance rate is 92.6%, operating efficiency is 0.82 ha/h. The harvest baler runs in low speed 1 gear, the machine has high operation efficiency, high bundling rate of highland barley, good paving effect, reduced labor intensity, provides the mechanized efficiency of highland barley harvesting. Fuel consumption per hectare is 8.05 kg.hm-2, and the three shifts are without fault, to sum up, it can meet the requirements of highland barley harvesting and baling. The above research can provide a reference basis for the design of the highland barley harvesting baler. [ABSTRACT FROM AUTHOR]

Aiming at the problems of single mechanical performance, multi-person operation and low operation efficiency of air-suction jujube harvesting in China, combined with the requirements of mechanized jujube harvesting in Xinjiang, this study designed a self-propelled jujube collection strip pick-up machine. The machine is mainly composed of crawler chassis, landing jujube collection strip device, separation and impurity removal device and hydraulic system. According to the jujube planting mode, the size of the crawler chassis is 1780 mm x 1650 mm x 310 mm. In order to simulate the effect of artificial collecting strips, a reciprocating collecting strip blowing head was designed with a height of 15 cm from the ground, a horizontal and vertical angle of 35° and 15° respectively. The model of the collecting fan is selected as 9-19-4A; the fluid simulation analysis of the separation and impurity removal box is carried out to verify the rationality of the box structure design. The performance of the picker was tested by pick-up efficiency, cleanliness, breakage, and impurity rates. The results show that when the forward velocity was about 0.40 ms1, the average pick-up efficiency could reach 752.7 km-h-1, the average pick-up cleanliness rate was 95.66 %, the average breakage rate was 2.68 %, and the average impurity rate was 3.64 %. The self-propelled jujube collection strip pick-up machine designed in this experiment meets the requirements of mechanized harvesting of jujube and can realize single-person remote control operation. [ABSTRACT FROM AUTHOR]

Pollination is critical for the production of many crops, and both insect- and wind-based pollination systems are increasingly disrupted by bloom asynchrony, weather events, and high demand for available insect pollinators. Artificial pollination systems can provide a security of yield even in poor pollination scenarios, and have been attracting increasing attention over the past decade. Here, we review pollen collection and pollen application technologies that have been employed to date. Major categories of mechanical pollination technology include: hand-pollination, handheld and backpack devices, vehicle-mounted devices, unmanned aerial vehicles (UAVs), and robotic and autonomous pollinators. The majority of the artificial pollination systems above are used to supplement natural pollination, but for some crops, these systems were found to perform adequately by themselves, including kiwifruit, olive, date palm, walnut, tomato, and hybrid maize seed. These systems often treat pollen as a system input, creating a chicken-and-egg problem in which the system is not economical without pollen and the pollen is not economical to collect without wide uptake of the system. To combat this, there has been success in developing mechanical harvesters for some crop plants (particularly almond and maize), but future work is needed for artificial pollination to be a commercial reality for the increasing number of cropping systems that are experiencing pollination deficits. [ABSTRACT FROM AUTHOR]

Despite rapid advancements in the development of triboelectric nanogenerators (TENG), mechanical defects generated during their working condition limit the service lifetime of these devices. Polyester-based vitrimers can offer a solution to solve this issue via their dynamic bond exchange reactions. However, they often require high temperatures and a long time to crosslink, rendering them not useful for large-scale TENG fabrication. To solve these issues, a self-healable vitrimer-based triboelectric nanogenerator (VITENG) is developed based on diacrylate poly(dimethylsiloxane) (AA-PDMS) via a fast thiol-Michael reaction. By including 2,3-dihydroxypropyl methacrylate (DHPMA), hydroxy end dangling side chains are generated in the matrix, which increase the PDMS network's flexibility and transesterification efficiency. Efficient transesterification occurs on the abundant dynamic ß-hydroxy ester bonds in the PDMS network, resulting in 100% efficient mechanical damage repair. The VITENG demonstrates a good performance with an output voltage of 135 V under a load of 10 N, demonstrating the potential for mechanical energy harvesters with long lifetimes and high design flexibility. [ABSTRACT FROM AUTHOR]

In mechanized timber harvesting operations, it is possible to verify ergonomic inadequacies, such as poor visibility and inappropriate postures, which can cause risks to the safety and health of workers, with effects on the operational performance of the machines. In this context, the objective of this work was to evaluate the effects of the positioning of the coupling crane in harvesters concerning the visibility and postures of forestry operators. For this, the study was carried out in clear-cutting operations in eucalyptus stands, evaluating a harvester with a frontal coupling crane and another with lateral coupling, as well as operators per machine. To determine effective times and typical postures, filming and freezing of images were performed. Then, the Skogforsk and Rapid Upper-Limb Assessment (RULA) methods were used to assess visibility and posture, respectively. Angulation and posture data were compared between machines by the Student's t test. Front and side visibility remained within acceptable limits, but the side crane harvester required operators to have an average head tilt angle of 15°, 50% higher than with the front crane. Consequently, in the postural evaluation, the one with the lateral crane presented score 3 and action level 2 86% of the time, suggesting further investigations, while the other presented score 2 and action level 1 81% of the time, being acceptable if not maintained or repeated for long periods. Therefore, the positioning of the crane coupling on the machine requires a reorganization of the workstation, mainly the machine's display. [ABSTRACT FROM AUTHOR]

The research was carried out under the conditions of harvesting and repair of the Agricultural Base Business Unit (UEBA) "Sierra Maestra", in the New Holland L-521, L-624, L-626 rice harvesters. The objective was estimating and checking the maintainability of the rice harvesters during daily technical maintenance, every 30 hours and during the harvest period under the conditions of "Los Palacios" Agroindustrial Grain Company (EAIG). Through mathematical analysis, average daily and periodic technical maintenance time every 30 h was determined. In the investigation, what the same authors did in 2017 was validated. Among the most significant results is that: for the harvesters evaluated, the maintainability curve shows that there is between 95.8...97% probability that the daily technical maintenance is carried out in two hours; while in technical maintenance every 30 hours the probability is 74...78% in the same period. [ABSTRACT FROM AUTHOR]

Safflower silk is one of the most important cash crops in the medical treatment and dye. The manual picking of safflower silk cannot fully meet the large-scale production at present. The mechanized harvesting can be expected to improve the safflower harvesting efficiency and labor cost-saving in the industrial planting. The complex environmental factors have made great difficulty to accurately identify and locate the safflower during mechanical picking, including the natural environment (such as the light and shelter), and the safflower characteristics (such as the small and dense target, as well as the different maturity). In this study, an improved YOLOv7 model was proposed to rapidly and accurately locate the safflower recognition in the complex environment. 1500 safflower images were established to divide into three types of samples, silk, bulb, and decay. The small target was found in the datasets with uneven sample size, especially the data of decay. The safflower sample dataset was produced to build the complex environment data for the real picking. Firstly, the Swin Transformer attention mechanism was added to the YOLOv7 network model, in order to improve the detection accuracy of the model for each classification sample, and the ability of the backbone network, especially to extract the small target features. Secondly, the Focal Loss function of the multi-classification was improved in the recognition rate of unbalanced samples under multi-class tasks, particularly for the target confidence loss and classification loss. The attenuation parameters γ was adjusted to balance the sample. The attenuation parameters were determined after experimental verification. Finally, the safflower detection network model was designed to meet the real-time and accurate detection requirements under the complex environment. The test results show that the best performance of the model was achieved in the attenuation parameters of 1.0, where the position of Swin Transformer was the layer 50. The average precision of the improved model reached 88.5% in each category sample, which was 7.0 percentage points higher than before. The average detection accuracy of the unbalanced category sample decay was 15.9 percentage points higher. Compared with the Faster RCNN model, the detection speed increased by three times, while the average accuracy increased by 9.7 percentage points; Compared with the Deformable DETR model, the detection speed increased by about 5 times, and the average accuracy increased by 16.5 percentage points. The improved model performed the best, in terms of the detection efficiency, detection speed, and model size. The improved model can also be expected to accurately detect the safflower, indicating the smaller parameters and the faster recognition speed suitable for the migration deployment on the safflower picking machinery. The finding can provide the technical support for the mechanized picking in real time. In the future research, the balance between species can be promoted to expand the number of samples from the data level in the harvesting machinery. [ABSTRACT FROM AUTHOR]

Physical activity involves movements, which can be considered sources of kinetic energy, that are expected to be important during sports activities. Several transducers can transform this energy into electrical energy. Piezoelectric generators are widely used, and several applications highlight their relevance. However, the generated output power is location dependent, and the analysis of the placement of this kind of generator can be challenging. In order to assess the availability of kinetic energy sources, an acceleration data analysis method is presented. Temporal and harvester model-based studies, using data from 17 inertial measurement units (IMUs) located across the whole human body, were conducted. The results show that piezoelectric cantilever-beam harvesters can be very sensitive to impacts. Extremity segments, such as the feet or hands, can be considered as good energy sources. The most relevant features are proposed as criteria to easily evaluate the harvestable energy sources. [ABSTRACT FROM AUTHOR]

Onions are manually harvested in the Philippines due to the unavailability of mechanical harvesters adaptable to local field conditions. Further, imported onion harvesters are not only expensive, but it is beyond the reach of local farmers. Hence, this study design and preliminary evaluation of onion harvester hand tractor implement conceptualized to adapt the local field conditions and increase profitability in onion production. The design combines digging, cleaning, and collecting onion bulbs simultaneously in one operation. The main assemblies of the implement include the frame, digger blade, soil-onion separation device, power transmission, and discharge cart. The implement has a total weight of 68 kg; an overall dimension of 1 230 mm × 570 mm ×500 mm (l × w ×h); and a power requirement of 2.08 hp. The machine was fabricated by a local manufacturer using available standard materials. The treatments were the rotary speed of soil-onion separation device; 100 rpm, 208 rpm and 333 rpm. The data were analyzed using Completely Randomized Design (CRD) and Tukey’s Honest Significant Difference (THSD) to further test the level of significance. Results revealed that the actual field capacity, harvesting capacity, and harvesting efficiency were 0.027 ha h -1 , 299.05 kg hr -1, and 70.93%, respectively. Hence, this study paved a way for mechanizing onion harvesting at a lower cost and further use of the machine to other root crops can be explored. [ABSTRACT FROM AUTHOR]

Human power is the main resource in all production units like agriculture. Suitable working condition is essential to enhance job satisfaction and productivity of human resources. Stop watch time study was used in this study for the first time in Iran's horticulture sector in order to give correct estimation of laborers' productivity for pomegranate harvesting while mechanized harvester machines are limited. The pomegranate harvesting process was broken into its seven elements. The require time for doing each element was recorded and necessary allowances for each element was obtained from time study standards tables. Ten out of 37 gardens were randomly chosen and the works of three laborers from each garden were observed and recorded with three replications. Level of job satisfaction was investigated using Job Descriptive Index (JDI) questionnaire to understand whether employing suitable number of laborers enhances job satisfaction. The results showed that two groups of laborers harvested pomegranate with different speeds, the middle-aged laborers (36-55 years old) required more allowances than the young laborers (20-35 years old) of laborers. Statistical analysis revealed high correlation between frequencies of picking pomegranate task and observed time by 92% (inverse relation) meaning that the sample laborers worked highly similar. The average productivity of young and middle-aged groups of laborers were harvesting 37 kg h -1 and 29 kg h -1 pomegranate, respectively. Accordingly, it was determined that six laborers are needed from the young group or eight laborers from the middle-aged group to harvest 22,000 kg ha-1 pomegranate in a working time of 12 days (8 h day-1 ). Using a suitable number of laborers in any work would lead to reaching actual laborers' productivity and on time work accomplishment besides high level of job satisfaction. The proposed methodology can be applied in other sectors/organizations with further investigation into enhancement of health and safety of laborers in different working conditions. [ABSTRACT FROM AUTHOR]

This paper describes a rotary piezoelectric wind energy harvester with bilateral excitation (B-RPWEH) that improves power generation performance. The power generating unit in the current piezoelectric cantilever wind energy harvester was primarily subjected to a periodic force in a single direction. The B-RPWEH adopted a reasonable bilateral magnet arrangement, thus avoiding the drawbacks of limited piezoelectric cantilever beam deformation and unstable power generation due to unidirectional excitation force. The factors affecting the power generation were theoretically analyzed, and the natural frequency and excitation force of the piezoelectric cantilever have been simulated and analyzed. A comprehensive experimental research method was used to investigate the output performance. The B-RPWEH reaches a maximum output voltage of 20.48 Vpp when the piezoelectric sheet is fixed at an angle of 30°, the Savonius turbine number is 3, and the magnet diameter is 8 mm. By adjusting the fixed angle of the piezoelectric sheet, the number of Savonius wind turbine blades, and the magnet diameter, the maximum voltage is increased by 52.38%, 4.49%, and 245.95%, respectively. The output power is 24.5 mW with an external resistor of 8 kΩ, and the normalized power density is 153.14 × 10−3 mW/mm3, capable of powering light-emitting diodes (LEDs). This structure can drive wireless networks or low-power electronics. [ABSTRACT FROM AUTHOR]

The advent of CubeSat constellations is revolutionizing the ability to observe Earth systems through time. The improved spatial and temporal resolutions from these data could assist in tracking forest harvesting by forest management companies or government organizations interested in monitoring the sustainable management of forest resources. However, differing characteristics of individual satellites in each constellation requires study into geometric and radiometric normalization of the imagery and tuning parameters for change detection algorithms. In this study, a method for the spatial and temporal detection of forest harvest operations using images from the PlanetScope constellation was developed and implemented for a managed forest in Ontario, Canada. Temporal smoothing was applied on Landsat-normalized PlanetScope values of the Normalized Differential Vegetation Index (NDVI), and change points were detected based on the first derivative of the NDVI trend. Detected changes were compared to known locations of harvesting machines. Results indicate that 80–90% of harvested areas were detected, with temporal errors of approximately 9–10 days for two sites. Overall, this study demonstrated that forest harvesting can be detected with relative accuracy, deriving previously unavailable levels of spatial and temporal detail and enhancing the ability of forest stakeholders to monitor the sustainable use of forest resources. [ABSTRACT FROM AUTHOR]

An improved YOLOv5 algorithm for the efficient recognition and detection of asparagus with a high accuracy in complex environments was proposed in this study to realize the intelligent machine harvesting of green asparagus. The coordinate attention (CA) mechanism was added to the backbone feature extraction network, which focused more attention on the growth characteristics of asparagus. In the neck part of the algorithm, PANet was replaced with BiFPN, which enhanced the feature propagation and reuse. At the same time, a dataset of asparagus in complex environments under different weather conditions was constructed, and the performance variations of the models with distinct attention mechanisms and feature fusion networks were compared through experiments. Experimental results showed that the mAP@0.5 of the improved YOLOv5 model increased by 4.22% and reached 98.69%, compared with the YOLOv5 prototype network. Thus, the improved YOLOv5 algorithm can effectively detect asparagus and provide technical support for intelligent machine harvesting of asparagus in different weather conditions and complex environments. [ABSTRACT FROM AUTHOR]

A review of specialized literature has been carried out to determine the main characteristics and importance of the base cutter of sugarcane harvesters. This mechanism is of vital importance for the correct cutting of the cane, hence developing an efficient base cutter and finding a reasonable base-cutting mode is key to successful mechanical harvesting. Various kinematic and construction parameters, such as cutting speed, oblique blade angle, cutting disc pitch angle and blade shape, influence the performance of base cutters. As a result of the investigation, the insufficient number of investigations focused on the impact cutting systems receive from dissimilar objects found in the ground was verified. On the other hand, abrasive wear is the main phenomenon that threatens the durability of the cutting segment, as well as the morphological and physiological characteristics of the cane, the correct preparation of the soils, the damages caused by the bad manipulation of the mechanism in the cutting process and the working speed. [ABSTRACT FROM AUTHOR]