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Bagging is a crucial step in the full cycle management of pear cultivation, with increasing labor costs annually, driving research on intelligent bagging equipment. We describe an intelligent bagging end-effector for pears, which employs the Yolov8 algorithm for fruitlets detection and the Semi-Global Block Matching (SGBM) algorithm to acquire three-dimensional spatial information of the targets. To address the computational limitations of embedded devices in agricultural intelligent equipment, we improve the YOLOv8 model by replacing its neck component with the Asymptotic Feature Pyramid Network (AFPN) and incorporating Context Guided (CG) blocks into the C2f module. These improvements significantly reduce the model’s parameters and size while enhancing detection accuracy. To provide accurate three-dimensional information to the end-effector, we use the SGBM algorithm to obtain depth information of the targets. We constrain the matching process based on the model’s detected candidate bounding boxes and binocular prior knowledge, which improves the matching accuracy of the model while reducing the computational load. Finally, we deploy the model and matching algorithm on a Jetson Nano, which serves as the controller for the bagging end-effector based on the vacuum negative pressure principle. Experimental results show that the improved model achieves a precision of 96%, an increase of 1.4% over YOLOv8, with the size reduced from 6.2M to 5.0M. The depth information accuracy obtained by the algorithm is within 3cm. The improved model, combined with SGBM, runs at 11.5 fps on the Jetson Nano embedded device, meeting real-time performance requirements.

The intelligent harvesting technology for jujube leaf branches presents a novel avenue for enhancing both the quantity and quality of jujube leaf tea, whereas the precise detection technology for jujube leaf branches emerges as a pivotal factor constraining its development. The precise identification and localization of jujube leaf branches using real-time object detection technology are crucial steps toward achieving intelligent harvesting. When integrated into real-world scenarios, issues such as the background noise introduced by tags, occlusions, and variations in jujube leaf morphology constrain the accuracy of detection and the precision of localization. To address these issues, we describe a jujube leaf branch object detection network based on YOLOv7. First, the Polarized Self-Attention module is embedded into the convolutional layer, and the Gather-Excite module is embedded into the concat layer to incorporate spatial information, thus achieving the suppression of irrelevant information such as background noise. Second, we incorporate implicit knowledge into the Efficient Decoupled Head and replace the original detection head, enhancing the network's capability to extract deep features. Third, to address the issue of imbalanced jujube leaf samples, we employ Focal-EIoU as the bounding box loss function to expedite the regression prediction and enhance the localization accuracy of the model's bounding boxes. Experiments show that the precision of our model is 85%, which is increased by 3.5% compared to that of YOLOv7-tiny. The mAP@0.5 value is 83.7%. Our model's recognition rate, recall and mean average precision are superior to those of other models. Our method could provide technical support for yield estimation in the intelligent management of jujube orchards. [ABSTRACT FROM AUTHOR]

Cellular demise is a pivotal event in both developmental processes and disease states, with mitochondrial regulation playing an essential role. Traditionally, cell death was categorized into distinct types, considered to be linear and mutually exclusive pathways. However, the current understanding has evolved to recognize the complex and interconnected mechanisms of cell death, especially within apoptosis, pyroptosis, and necroptosis. Apoptosis, pyroptosis, and necroptosis are governed by intricate molecular pathways, with mitochondria acting as central decision-makers in steering cells towards either apoptosis or pyroptosis through various mediators. The choice between apoptosis and necroptosis is often determined by mitochondrial signaling and is orchestrated by specific proteins. The molecular dialogue and the regulatory influence of mitochondria within these cell death pathways are critical research areas. Comprehending the shared elements and the interplay between these death modalities is crucial for unraveling the complexities of cellular demise. [ABSTRACT FROM AUTHOR]

As a new type of unconventional natural gas resource, shale gas plays a vital role in energy supply. In order to deeply understand the shale fracture seepage characteristics, filled and unfilled fracture seepage tests were carried out on shale samples with different fracture surface topography with the use of self-developed shale fracture seepage testing equipment. The fitting formula that the seepage discharge decreased as a negative exponential function with the increase in normal stress was obtained in the unfilled fracture seepage test; the fitting coefficient had a good logarithmic and exponential function relationship with joint roughness coefficient JRC and surface development interface area ratio Sdr. Meanwhile, the modified cubic law was obtained by adding the correction coefficient. The correction coefficient had an exponential relationship with the anisotropy value Ka. Compared with the unfilled one, the fracture surface topography had little effect on the seepage discharge when it was filled. The experimental results show the effects of water head difference, fracture surface topography, particle size, and thickness of filling sand on shale fracture seepage characteristics under different normal stress conditions, which have a certain significance for improving the efficiency of shale gas production. [ABSTRACT FROM AUTHOR]

A multi-functional modifier, which could improve the mechanical and thermal performance simultaneously, is significant in composites production. Herein, inspired by the chemistry of mussel, an interfacial modifier named FPD was designed and synthesized through one simple step, which was attached by three functional groups (including catechol, N-H bond, and DOPO). Due to the innate properties of each functional group, FPD played multiple roles: adhere to the ramie fibers from catechol and cure with the epoxy resin from -NH-, an antiflaming property from DOPO, and the compatibilizer between ramie fibers and epoxy resin was also improved by changing the polarity of ramie fiber. All of the above functions can be proved by means of water contact angle (WCA), atomic force microscope (AFM), and scanning electron microscopy (SEM), etc. After solidification, the ramie fiber/epoxy composites demonstrated superior performances in terms of good mechanical properties and excellent flame retardant property. With the addition of 30 wt.% FPD, the tensile strength and modulus of the ramie/epoxy composite showed an improvement of 37.1% and 60.9%, and flexural strength and modulus of the composite were improved by 8.9% and 19.3% comparing with no addition composite. Moreover, the composite could achieve the goal for V-0 rating in the UL-94 test and LOI value was 34.6% when the addition of FPD reached 30 wt.%. This work provided us with an efficient method for fabricating nature fiber/epoxy composites with good properties. [ABSTRACT FROM AUTHOR]

Energy efficiency and resource utilization are considered to be necessary for sustainable development. Organic phase change materials (PCMs) as an effective thermal energy storage tool have attracted great interest, but non-renewable ingredients, low stability and their unsafe nature largely restrict their sustainability. Herein, a series of bio-based benzoxazine-derived PCMs were developed, in which green preparation, efficient energy conversion, and safe utilization can be simultaneously achieved. Through the Mannich condensation reaction, novel PCMs can be easily synthesized with good yield and high atom economy by combining natural 3-pentadecylphenol (a cardanol derivative) and amine sources. The resulting PCMs exhibited adjustable latent heat (48.78–147.02 J g−1) by altering raw materials, which are close to their commercial unsustainable counterparts. As an example, C-aa-12 also showed considerable recycling ability after 100 times repeated use. In addition, due to the designed structure, as-prepared PCMs also possessed more excellent properties of thermal stability (Td50% was increased by 65.1%) and flame retardancy (HRR was reduced by 39.4%) compared with traditional ones, making them promising in a wider application field. [ABSTRACT FROM AUTHOR]

Currently, there is a great need to develop methods for the selective detection of fluoride anions (F-) owing to their toxicity in the environment and biological function in living systems. In this study, we developed a new fluorescent probe (probe 1) employing a Si-O bond as a highly selective recognition receptor for detecting F- via intramolecular charge transfer. Probe 1 could detect F- quantitatively using the turn-on fluorescence spectroscopy method with excellent sensitivity in the range of 4-38 μM and a detection limit of 0.26 μM; the detection time was < 17 min. We anticipate that probe 1 would be used widely to monitor F- in the environment. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Design and development of a high power, widebandwidth W-band travelling wave tube (TWT) is presented in this paper. The design and simulation covers folded waveguide (FWG) circuit, electron gun, periodical permanent magnet system, and coupling window with the emphasis on the FWG optimization and particle-in-cell simulation by Computer Simulation Technology (CST) particle studio. Two TWT prototypes have been developed and tested, which demonstrate over 30-W output power in frequency between 91 and 101 GHz with over 30-dB saturated gain. Maximum power was found to be about 40 W around 95 GHz, while the flat output power curve under same drive level was observed. [ABSTRACT FROM PUBLISHER]

W-band TWTs are key devices for high-frequency and high-power amplifiers used in high-resolution imaging applications. This paper presents the design, simulation, and fabrication of W-band pulsed TWTs. For higher power and broader bandwidth, TWTs have been developed using all-metal folded waveguide (FWG) slow-wave structures, diamond-disc windows, and horseshoe-shaped carbonized alumina attenuators. The test results show that W-band FWG pulsed TWTs can reach over 100 W output power with 6.7 GHz bandwidth and over 33 dB saturated gain at 20% duty cycle, while the maximum output power exceeds 200 W. [ABSTRACT FROM AUTHOR]

Hydro-floating ship lifts are a milestone in the field of high dam navigation. In order to ensure the running safety of a hydro-floating ship lift, the effective integration of a numerical simulation method and cloud model theory was carried out to deal with the hydrodynamic risks presented by water surface deviations from the shafts in the filling–emptying system such as a lock. In this study, the average values of water surface deviation from the shafts were 0.2, 0.22 and 0.24 m, through numerical simulation on a similar hydro-floating ship lift at the lifting heights of 80, 100 and 120 m, respectively. An increase in the lifting height causes the water surface deviation from the shafts to increase, and the hydrodynamic risk is greatly increased in the equal inertial pipeline filling–emptying system. In addition, the water surface deviations from the shafts of the equal inertial pipeline and longitudinal culvert filling–emptying system like a lock were compared. The longitudinal culvert was better at optimizing running safety in the filling–emptying system and dealing with the uncertainty of water surface deviation from the shafts. The results show that the numerical simulation method and cloud model theory can effectively control the risk of water surface deviation from the shafts and can be used to aid in decision-making for risk prevention in relation to hydro-floating ship lifts. [ABSTRACT FROM AUTHOR]

W-band Folded Waveguide (FWG) TWTs with moderately high-power and broad-bandwidth are a key device for many applications, such as radar and imaging systems. This letter presents the development of a 10 GHz bandwidth 100 W W-band FWG pulsed TWT. The test results show that this TWT is capable to offer over 100 W output power with 10.1 GHz bandwidth. [ABSTRACT FROM PUBLISHER]