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Traditional sheet metal processing enterprises are facing problems such as upgrading manufacturing systems, lower material utilization rate, and lower efficiency of CNC machining. In this paper, we design a flexible manufacturing production line for sheet metal processing of complex parts, use the DQN algorithm to optimize the scheduling of each part of the work in the production process of the production line, and optimize the adaptability of the DQN algorithm by using the action selection strategy and the reward function and so on. Then, the digital twin simulation system is constructed to simulate the process of a flexible manufacturing production line for sheet metal processing. The results show that the DQN algorithm can effectively assign the corresponding processing machines and processes to the workpieces in the production line, and the digital twin simulation system can also accurately simulate the actual situation of the production line. Meanwhile, it is found that the optimized production line can reach 87.52% of the production beat balance rate, which is 23.64% higher than the original production line balance rate, and it can improve the average utilization rate of the main operating units in the production line. The optimized production line proposed in this paper can effectively solve the practical problems in sheet metal production lines, improve the mobility of the production line and corporate efficiency, and provide new ideas for the lean production management of large-scale machinery manufacturing enterprises.

Digital twin technology plays a crucial role in completing the virtual mapping of the physical workshop, enabling production monitoring and process optimization. New energy batteries are a form of green energy with advantages such as high energy density, environmental protection, and beneficial safety. The assembly line for new energy batteries is essential in efficiently obtaining battery packs of diverse varieties and high quality. This paper presents three assembly design schemes for square lithium iron phosphate battery packs as an example. By comparing the characteristics of different schemes, scheme C was selected as the preferred option for conducting three-dimensional modeling of the assembly line. This paper utilizes digital twin technology to create a digital representation of the battery pack assembly process. The process flow of the designed production line can be tested. The loading time, equipment idle time, fault time, blocking waiting time, material shortage waiting time, etc., of each workstation in the production line can be accurately calculated. Optimize the production process flow, reduce resource occupation, and save a large amount of human and material resources.

Poor-cross-linking vs Tight-cross-linking between the carbon sheets.

Given the big gap between rural areas and cities and developed areas of China in basic education, it is of great significance to train a large number of excellent teachers for basic education in the vast rural areas so as to boost basic education there and achieve educational equity. Hanshan Normal University is a regional normal university located in Chaoshan, Guangdong, China. The Chemistry Education major aims to foster outstanding chemistry teachers for rural middle schools in Guangdong, especially for the Chaoshan region. The university is committed to forming a reasonable knowledge structure for Chemistry Education majors, improving their experimental skills and capabilities in experimental design and educational research while cultivating their emotion in taking root in rural areas as well. Practice has proven that this program for training outstanding chemistry teachers for rural middle schools is fruitful.

Inflammatory bowel disease (IBD) is a chronic and potentially life-threatening inflammatory disease of gastroenteric tissue characterized by episodes of intestinal inflammation, but the underlying mechanisms remain elusive. Here, we explore the role and precise mechanism of Van-Gogh-like 2 (VANGL2) during the pathogenesis of IBD. VANGL2 decreases in IBD patients and dextran sulfate sodium (DSS)-induced colitis in mice. Myeloid VANGL2 deficiency exacerbates the progression of DSS-induced colitis in mice and specifically enhances the activation of NLRP3 inflammasome in macrophages. NLRP3-specific inhibitor MCC950 effectively alleviates DSS-induced colitis in VANGL2 deficient mice. Mechanistically, VANGL2 interacts with NLRP3 and promotes the autophagic degradation of NLRP3 through enhancing the K27-linked polyubiquitination at lysine 823 of NLRP3 by recruiting E3 ligase MARCH8, leading to optineurin (OPTN)-mediated selective autophagy. Notably, decreased VANGL2 in the peripheral blood mononuclear cells from IBD patients results in overt NLRP3 inflammasome activation and sustained inflammation. Taken together, this study demonstrates that VANGL2 acts as a repressor of IBD progression by inhibiting NLRP3 inflammasome activation and provides insights into the crosstalk between inflammation and autophagy in preventing IBD. Although NLRP3 inflammasome activation and impaired autophagy are linked to inflammatory bowel disease (IBD), the underlying mechanisms remain unclear. This study shows that VANGL2 reduces IBD progression by recruiting the ubiquitin ligase MARCH8 to regulate NLRP3 activation through OPTN-mediated autophagy. [ABSTRACT FROM AUTHOR]

Recent studies have highlighted the crucial role of abiotic processes, such as photodegradation and microclimatic fluctuation, in accelerating dryland litter decomposition. In grasslands, substantial amounts of dead plant material persist upright above the soil surface after senescence, experiencing distinct microclimatic conditions compared to surface litter. However, our understanding of how ultraviolet (UV) exposure and microclimatic conditions influence their decomposition is limited. To address this knowledge gap, we conducted a field experiment manipulating UV radiation for both soil surface litter and standing litter and monitored their microclimatic conditions in a semi‐arid grassland. Our findings indicate that UV exposure enhanced the decomposition of soil surface litter by alleviating the constraint of lignin on litter decomposition, while having no significant influence on standing litter. Although the mean levels of thermal‐hydric conditions were lower, more intense fluctuation of temperature and air humidity was detected in standing litter. These higher‐level microclimatic fluctuations facilitated the release of dissolved organic carbon, potentially increasing the availability of labile substrates to microbes. Meanwhile, standing litter released more photo‐sensitive phenols, leading to decreased sensitivity to UV exposure. Consequently, while UV exposure initially increased standing litter decomposition during the early stage, its influence eventually diminished. These findings underscore the critical yet differing roles of microclimatic conditions and UV exposure in the decomposition of standing and surface litter. Relying solely on knowledges derived from surface litter decomposition and microclimate conditions may not accurately capture the patterns of grassland litter degradation. Plain Language Summary: The limited precipitation in drylands is widely believed to restrict litter decomposition. However, the observed litter decomposition rates in these regions often exceed model predictions based on climatic conditions. In arid and semi‐arid steppes, the sparse vegetation cover results in intense ultraviolet (UV) radiation reaching soil surface, thereby triggering photodegradation of the recalcitrant compounds in litter. Additionally, substantial dead plant materials persist standing for months to years, and undergoes more intense warm‐cold and wet‐dry cycles. However, there have been limited studies assessing the intricate interplay between UV radiation and microclimate fluctuations on litter decomposition in drylands. In this study, we found that UV radiation facilitated the degradation of recalcitrant compounds and enhanced litter degradability of soil surface litter. More intense temperature and humidity fluctuations increased the concentration of dissolved organic carbon in standing litter. This increase could provide more labile substrate to decomposers, consequently accelerating litter decomposition. Moreover, microclimatic fluctuation enhances the loss of photo‐sensitive compounds in litter, reducing litter's sensitivity to UV exposure. Our study highlighted the significant role played by the interaction between climatic conditions and UV radiation in driving litter decomposition in water‐limited steppes, contributing to a better understanding of carbon turnover in dryland ecosystem. Key Points: The degradation of soil surface litter was mainly driven by warmer and wetter microclimate and ultraviolet (UV) exposureGreater microclimatic fluctuation in standing litter enhanced the release of dissolved labile carbon, thereby accelerating its decompositionGreater microclimatic fluctuation increased the loss of photo‐sensitive compound and weakened sensitivity of standing litter to UV radiation [ABSTRACT FROM AUTHOR]

In China, many cities are building themselves the transit metropolis, and the reasonable evaluation of level of service (LOS) of public transport system (PTS) is one important aspect. However, to determine the overall LOS is hard because the distribution of service in PTS is not homogeneous with regard to time and space. To address this problem, this study proposes a general framework to determine the LOS scale of PTS based on the distribution of service quality. Under the framework, two classification methods are discussed. Method 1 uses two parameters, the mean and coefficient of variation to model the distribution, and Method 2 is an existing approach that only considers mean. Then the specific use of the framework is expounded for the service attribute of crowding, and Beijing subway line LOS is evaluated. The line LOS is divided into I-IV, whose threshold is expressed as a function of mean and coefficient of variation. The results show that 57.8% of the sample points are in the most crowding level IV in morning peak hours by Method 1, but 60.9% of sample points are in a comfortable level II by Method 2, and the former is more consistent with reality. In addition, it reveals which lines and time periods need to improve the service level. The research proves the feasibility of considering the service distribution to determine the overall LOS of PTS, and it is useful for capturing more detailed information of the system performance in time and space. This research can provide an approach for evaluating and helping to improve the overall service level of PTS for public transport authorities., Author(s): Min Wang [1]; Baohua Mao (corresponding author) [1]; Yanqiang Yang [1]; Ruijia Shi [2]; Junsheng Huang [1] 1. Introduction With the development of social economy and residents' living standards, [...]

The first-mile service (FMS) refers to the modal choice for the first part of a commuting journey. A well-designed FMS can provide a seamless travel to access public transport services. This research was driven by the efficiency of different travel modes (e.g. taxi, shared bike, bus) in the FMS. Based on realistic travel experience, an expected utility model for each travel mode was developed. Then, a framework based on evolutionary game theory was designed to deal with the issue of passengers' dynamic interactions during the FMS. Both infinite- and finite-population scenarios were considered. The simulation results showed that walking is the first choice for passengers in comfortable weather and taking a taxi is the first choice in adverse weather. After the implementation of effective strategies, passengers' travel efficiency increases simultaneously. As such, effective strategies such as shared electric bikes, customised buses and taxi-sharing behaviour are encouraged in FMS planning. [ABSTRACT FROM AUTHOR]

The associations of arbuscular mycorrhizal (AM) or ectomycorrhiza (EcM) fungi with plants have sequentially evolved and significantly contributed to enhancing plant nutrition. Nonetheless, how evolutionary and ecological forces drive nutrient acquisition strategies of AM and EcM woody plants remains poorly understood. Our global analysis of woody species revealed that, over divergence time, AM woody plants evolved faster nitrogen mineralization rates without changes in nitrogen resorption. However, EcM woody plants exhibited an increase in nitrogen mineralization but a decrease in nitrogen resorption, indicating a shift towards a more inorganic nutrient economy. Despite this alteration, when evaluating present‐day woody species, AM woody plants still display faster nitrogen mineralization and lower nitrogen resorption than EcM woody plants. This inorganic nutrient economy allows AM woody plants to thrive in warm environments with a faster litter decomposition rate. Our findings indicate that the global pattern of nutrient acquisition strategies in mycorrhizal plants is shaped by the interplay between phylogeny and climate. [ABSTRACT FROM AUTHOR]

Language learner strategies (LLS) have long been viewed as a variable of individual differences, or as cognitive skills. This study, focusing as it does on the data taken from a series of focus groups with 47 senior secondary students in mainland China, seeks a new interpretation of strategy development and use from a sociocultural perspective. Evidence provided from the focus-group discussions shows that in the mainstream exam-orientated culture in mainland China, the grade-getting goal was likely to determine the general orientation of strategies for a variety of classroom learning tasks and shape the changes in strategy use over time which emerge at different learning stages. The results also indicate that the processes of strategy development and use were mediated by learners' personal discourse patterns embedded in their situated learning experience; by cultural artifacts (tasks); and by interpersonal interactions with their teachers, peers and family members; and situated in their communities of language learning practices and social cultures. In addition, the study underlines the need to take into account learning goals and the nature of learning tasks in LLS research, and to create a situated strategy development community as part of strategy instruction or training programs. (Contains 3 tables and 2 notes.)