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As is well known, intelligence and efficiency are important development directions for modern agriculture. The harvesting header, as key components of crop harvesters, have significant implications for achieving intelligent control of their working height, which has a notable impact on reducing harvest loss. To understand the current state of intelligent control technology for the working height of a crop harvesting header, and to explore their application potential, this article provides a relatively systematic literature review. Firstly, we analyzed the structure and principle of the harvesting header of typical grain and oil crops such as rice and peanuts. Secondly, we briefly described the current methods for controlling the working height of the harvesting header. They mainly use two methods: mechanical profiling and electro-hydraulic profiling. Thirdly, we focused on researching and analyzing the measurement methods and control algorithms for the working height of the harvesting header. Finally, we pointed out the problems in the current height control of the harvesting header. These problems mainly include insufficient measurement accuracy of working height in complex terrain, slow response and large delay of working height hydraulic control system, incompatibility between working height control models and strategies, and relatively single working height measurement methods.

The aim of this study was to determine the muscle load reduction of the upper extremities and lower extremities associated with wearing an exoskeleton, based on analyses of muscle activity (electromyography: EMG) and the AnyBody Modeling System (AMS). Twenty healthy males in their twenties participated in this study, performing bolting tasks at two working heights (60 and 85 cm). The muscle activities of the upper trapezius (UT), middle deltoid (MD), triceps brachii (TB), biceps brachii (BB), erector spinae (ES), biceps femoris (BF), rectus femoris (RF), and tibialis anterior (TA) were measured by EMG and estimated by AMS, respectively. When working at the 60 cm height with the exoskeleton, the lower extremity muscle (BF, RF, TA) activities of EMG and AMS decreased. When working at the 85 cm height, the lower extremity muscle activity of EMG decreased except for TA, and those of AMS decreased except for RF. The muscle activities analyzed by the two methods showed similar patterns, in that wearing the exoskeleton reduced loads of the lower extremity muscles. Therefore, wearing an exoskeleton can be recommended to prevent an injury. As the results of the two methods show a similar tendency, the AMS can be used.

Currently, wire and arc additive manufacturing (WAAM) is mainly done by planning the torch movements layer wise. The height step between the layers is derived from preliminary experiments. Small deviation in the determination of the height step can accumulate over the layers and lead to improper shielding gas conditions or a collision the between torch and the work piece. This makes continuous process monitoring necessary. To overcome these problems, a closed-loop layer height control strategy is beneficial. For the development of a closed-loop height control strategy, it is necessary to have knowledge of the effective height step between the layers during manufacturing. The present study focuses on the development of a sensing method, which allows users to detect the contact tube to working distance (CTWD) in WAAM. The system was developed for short circuit mode of gas-metal arc welding WAAM. The system can also provide information on whether the torch passes over weld beads crossing the weld track or other geometric irregularities existing in the z -direction. Several characteristic values of the process were detected and were matched to the actual CTWD. The accuracy of the sensing method was evaluated, and based on the measured correlation and standard deviation, the electrical resistance during short circuit monitored the CTWD best.

In this study, a 4UM-120D electric leafy vegetable harvester was employed as the research object. An automatic control system was created to maintain the cutter’s height above the ground within ±2% of the desired value. The intention was to reduce the operators’ work intensity while improving the leafy vegetable harvester’s working quality. The automatic control system for the cutter height from the ground was explained, along with its structure and operating philosophy. MATLAB was used to establish the two-phase hybrid stepper motor’s mathematical electrical equation and mechanical equation models. An analysis was carried out on the fundamentals and differences between position PID and incremental PID control algorithms. Utilizing incremental PID in combination, the control strategy for the harvester cutter height from the ground was built, and an automatic control system was produced under the corresponding control strategy. The stability, accuracy, and rapidity of the automatic control system of the cutter height from the ground under the incremental PID control strategy were analyzed by simulating different actual working conditions with MATLAB/Simulink and taking the steady-state transition time as the evaluation index. The test results show that when the deviation between the current value and the set value was greater than 2%—that is, when the harvester was in the condition of suddenly crossing the ditch or suddenly climbing the slope—the automatic control system based on the incremental PID control strategy had a good dynamic response performance and stability. This resulted in the automatic control function of the harvester cutter height off the ground being achieved. When the rotation angle PID control algorithm’s proportional coefficient is Kp = 4.665, the rotation speed PID control algorithm’s proportional coefficient is Kp = 5.65 and its integral coefficient is Ki = 3.86, and the current PID control algorithm’s proportional coefficient is Kp = 0.5455 and its integral coefficient is Ki = 30.4578. The harvester abruptly crossed a ditch while operating steadily, and the automatic control system’s steady-state transition time for the height of the cutter off the ground was 1.0811 s. The harvester abruptly climbed a slope while operating steadily, and the automatic control system’s steady-state transition time for the height of the cutter off the ground was 1.1185 s. Data from the field tests revealed a degree of reliability in the simulation test results. The study offered a strategy for raising the harvester quality for leafy vegetables while lowering the operator workload.

The distributed optical fiber sensing (DOFS) is a technique that can obtain full spatial and temporal information concerning the behavior of a large range of measurand fields along a fiber path and realize the distributed monitoring of the overburden section under mining. To calculate the height of water-flowing fractured zone caused by the exploitation of coal, this study employed distributed optical fiber sensors with OSI-C-S optical frequency domain reflectometry (OFDR) technology and designed a similar-material model test based on the engineering geological conditions of Daliuta Coal Mine. Through the test, deformation characteristics of overlying strata were studied, the linear relationship was summarized between the strain gradient and the shear stress measured by fiber sensors when the rock layer cracks, and a method was proposed of using the measured strain to measure the height of the water-flowing fractured zone in overlying strata. The test results show that there are several locations where the sign of the shear stress changes (positive to negative or vice versa) in the overlying strata during the initial stage of coal seam mining. As the working face advanced, the change locations gradually concentrated at the place where the rock cracks. By identifying the breakpoints of the rock and the locations where the sign of the shear stress measured by fiber sensors changes, this paper calculated the height of the water-flowing fractured zone in Daliuta Coal Mine. After comparing the height with the abscission layer position in the model test and the predicted height by the empirical formulas in the specification, it has been found that the three results are basically consistent, which in turn verifies the accuracy of this method.

FIRST WORKSHOP OF THE INTERNATIONAL CLOUD WORKING GROUP (ICWG) What: The first ICWG workshop, or ICWG-1, drew ∼85 attendees (including algorithm/product developers, cloud modelers, weather forecasters, and climate scientists) and covered a wide range of topics concerning the remote sensing of cloud parameters; related applications and issues, specifically in cloud detection, cloud modeling for remote sensing, severe weather applications, level 2 retrievals and uncertainties; and the establishment of a decadal cloud record for climate research with well-defined uncertainties. ICWG has several topical groups (TGs), six of which, underlined below, were convened during ICWG-1 in the order of their importance on satellite cloud products and applications: * Cloud Masks, * Calibration of Passive Imagers, * Use of Combined Sensors for Cloud Retrievals, * Cloud Modeling for Remote Sensing, * Cloud Height for Wind Applications, * Cloud Retrievals over Snow and Ice Surfaces, * Severe Weather Applications, * Validation Sources and Strategies, * Assessment of L2 Passive Imager Cloud Parameter Retrievals, * Assessment of Retrieval Uncertainties, * Aggregation Methods for Climate Applications, and * Assessment of Cloud Parameter Data Records for Climate Studies. Questions raised regarding the current GEWEX format included whether the current L3 spatial resolution (1° × 1°) would be sufficient for current and future model needs; whether to add or change included variables; based on the steady increase in AVHRR- and HIRS-derived records whether a method to address satellite orbital drift should be included; whether averaging standards should be developed to account for VIS channel saturation for optical thickness...