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At present, potato seeders in China generally have poor uniformity of seed rows and high coefficients of variation in plant spacing during seed rows, causing difficulties for subsequent mechanized plant protection and harvesting. Based on the effect of seed discharge to analyze the sowing process, a potato seed discharger with a double-layer seed picking spoon structure was designed. By analyzing the seed discharging mechanism and its operation process, the shape and size structural parameters of the seed picking spoon were determined. Finite element simulation of the seed pickup process and seed carrying process of the seed discharging mechanism was carried out by EDEM software to determine the double-layer seed scoop scheme and the range of factors for subsequent tests. A two-factor test was conducted with seeding line speed and seed drop height as test factors, and plant spacing coefficient of variation and seed potato lateral offset dispersion as test indexes. The test results showed that the double-layer seeding spoon chain seeder reduced the coefficient of variation in plant spacing by 5.8%, and the dispersion in lateral offset by 5.5 mm, compared with the single seeding spoon seeder, when the seeding speed was 0.184 m/s and the height of falling seed was 9 cm. [ABSTRACT FROM AUTHOR]

In this study, a longline aquaculture facility with lantern nets off the coast of northern China was modelled to conduct hydrodynamic tests starting from the culture unit to the entire facility under various current and wave conditions. The experimental results indicated that the drag coefficients of the lantern net model with weights of 0.5, 0.75, and 1.0 kg were 0.75, 0.83, and 0.91, respectively, in the Reynolds number range of 1 × 104–1 × 106. The current-driven upstream mooring line was more dominant than the wave-driven tension, and a simplified model of the longline facility accurately predicted the mooring line tension under the current conditions. The scope of the mooring line (defined as the length of the mooring line related to the water depth) played an important role in eliminating an order of magnitude difference in mooring tension under the wave conditions. The amplitudes of the vertical movement of the longline facility were smaller than the wave height when L/Lm was less than 1.5. Therefore, detailed information is needed to better understand the hydrodynamic characteristics and motion response of longline aquaculture facilities for the safe operation of longline structures in offshore environments, in order to process high-quality oyster products. [ABSTRACT FROM AUTHOR]

Tungsten enrichment during the formation of giant W deposits is thought to be related to magmatic and hydrothermal processes. However, the mechanisms of W enrichment and their role in controlling ore formation remain unclear. Zircon is a ubiquitous accessory mineral that can provide a record of the physicochemical conditions during mineralization. Dahutang in South China is a giant W deposit (1.89 Mt WO3 at 0.18%) associated with the late Mesozoic granites. In this study, we report new zircon morphological, geochronological, and chemical data for the most evolved Li-mica albite granite in the Dahutang deposit, in order to determine the processes of W enrichment. We classified the zircons into three types based on their appearance and composition. Type-IA and -IB zircons (ca. 145 Ma) successively crystallized from metasedimentary-derived magmas (δ18O = 8.9 ± 0.3‰) at 786–732 °C. Type-II zircons formed by interaction between volatile-rich melts and Type-I zircons at 669 ± 39 °C. Type-III zircons formed by autometasomatism of earlier Type-I and -II zircons, which involved exsolved hydrosilicate fluids. Our numerical model shows that the granitic melts have undergone > 95% fractional crystallization and experienced metasomatism by hydrosilicate fluids, during which the rare-metals (W, Nb, and Ta) were extensively enriched. Furthermore, we compiled data for ten W deposits across South China to investigate the key factors controlling the formation of giant W deposits. The strong correlation (R2 = 0.79) between WO3 tonnage and zircon Hf content indicates that an extensive and multi-stage evolution may be the key factor controlling the formation of giant W deposits. [ABSTRACT FROM AUTHOR]

The corpus, being an effective tool, is utilized in multiple fields. One of them is the Translation. However, this resource isn't used frequently in translation studies when one of the languages in question is classical chinese (written language used anciently in China). And when it comes to an ad hoc parallel corpus, the steps of how to create it are usually omitted by researchers who make such investigations. The objective of this article is to present how to elaborate a classic Chinese-Spanish parallel corpus taking as example the historic novel Romance of the Three Kingdoms and its two translations into Spanish. To reach the objective, we have described the problem of creation and exploitation of this type of corpus, following the order of the phases of the process. We've found that some of the phases are universal while other phases are unique for old languages and for the linguistic combination Chinese-other language. And in this latter case, there's a lack of effective applications. With the current work, we hope to offer useful information to those scholars who are willing to carry out their own investigations based on self-built parallel corpus and at the same time related to the classic Chinese works. [ABSTRACT FROM AUTHOR]

Intelligent part‐to‐picker systems are spreading across a broad range of industries as preferred solutions for agile order fulfillment, wherein mobile racks are carried by robots and moved to stations where human pickers can pick items from them. Such systems raise the challenge of designing good work schedules for human pickers; they also give rise to a new class of operational scheduling problems in human–robot coordinated order picking systems. This work studies the problem of finding a suitable robot schedule that takes into account the schedule‐induced fluctuation of the working states of human pickers. A proposed model enables mobile racks with various workloads to be assigned to pickers, and schedule the racks that are assigned to every picker to minimize the expected total picking time. The problem is formulated as a stochastic dynamic program model. An approximate dynamic programming (ADP)‐based branch‐and‐price solution approach is used to solve this problem. The developed model is calibrated using data that were collected from a dominant e‐commerce company in China. Pickers' working state transitions are modeled based on data obtained from this warehouse. Counter‐factual studies demonstrate that the proposed approach can solve a moderately sized problem with 50 racks in under 2 minutes. More importantly, the approach yields high‐quality solutions with picking times that are 10% shorter than the solutions that did not consider schedule‐induced fluctuations of pickers' working states. [ABSTRACT FROM AUTHOR]

• Adaptive Zone-fusion Network for waxberry semantic segmentation was proposed. • We have captured and provided a comprehensive and complete dataset. • Improve segmentation accuracy and reduce the impact of various interferences. • Our research promotes the advancement of automated fruit harvesting technology. In China, waxberries are a specialty fruit that require large harvesting efforts each season. To ameliorate these issues, automated fruit-picking equipment has been widely developed within the last decade. However, most image analysis research used for waxberry segmentation contains issues such as incomplete datasets, insufficient segmentation accuracy, and susceptibility to interference. Here, we developed the Adaptive Zone-fusion Network (AZNet) that enables automated fruit harvesting and is designed to precisely segmentate waxberries in an orchard environment. Initially, we collected a diverse range of images to train and evaluate a better model, and found that AZNet demonstrated exceptional performance and achieved a mean Accuracy (mAcc) of 99.83%, mean Intersection over Union (mIoU) of 96.57%, and mean Dice coefficient (mDice) of 98.20%. To further validate AZNet's effectiveness, we compared several state-of-the-art (SOTA) models, including DeepLab V3, SegNet, PSPNet, U-Net, RefineNet, FCN, DANet, and FastSCNN. Along with these comparisons, we also performed an ablation study to substantiate the individual impact of each module within AZNet. Through these experiments, we found that AZNet exhibits the capability to achieve accurate semantic segmentation of waxberries in complex orchard environments, and is suitable for automated fruit harvesting devices. Ultimately, AZNet improves upon previous models by constructing information fusion modules through spatial attention, channel attention, Atrous Spatial Pyramid Pooling (ASPP), and graph convolutional methods, which can be utilized in the future to enhance other fruit-picking software to reduce fruit loss and the investment of human resources. [ABSTRACT FROM AUTHOR]

In this research, we study an extended version of the joint order batching and scheduling optimization for manual vegetable order picking and packing lines with consideration of workers' fatiguing effect. This problem is faced by many B2C fresh produce grocers in China on a daily basis which could severely decrease overall workflow efficiency in distribution center and customer satisfaction. In this order batching and sequencing problem, the setup time for processing each batch is volume-dependent and similarity dependent, as less ergonomic motion is needed in replenishing and picking similar orders. In addition, each worker's fatiguing effect, usually caused by late shift and repetitive operation, which affects order processing times, is assumed to follow a general form of logistic growth with respect to the start time of order processing. We develop a heuristic approach to solve the resultant NP-hard problem for minimization of the total completion time. For order batching, a revised similarity index takes into account not only the number of common items in any two orders but also the proportion of these items based on the vegetable order feature. To sequence batches, the genetic algorithm is adapted and improved with proposed several efficient initialization and precedence rules. Within each batch, a revised nondecreasing item quantity algorithm is used. The performance of the proposed heuristic solution approach is evaluated using numerical instances generated from practical warehouse operations of our partnering B2C grocer. The efficiency of the proposed heuristic approach is demonstrated. [ABSTRACT FROM AUTHOR]

Through combing the research literature of slim cigarette processing technology and processing equipment in China, it was pointed out that the research on processing technology of slim cigarette was mainly focused on the local research of tobacco cutting and stem cutting process. Due to the lack of in-depth and systematic research on the three links of threshing and redrying, tobacco primary processing, rolling and wrapping process, the research on processing technology of slim cigarette was difficult to support the process system of slim cigarette. The processing equipment of slim cigarette was mainly the processing equipment of the conventional cigarette by branching transformation, which only met the basic requirements of processing technology of slim cigarette, and systematic research need to be carried out on the optimization design and the improvement of the processing quality of slim cigarette. In the future, a "big technology" concept should be set up that combines the three links of threshing and redrying, tobacco primary processing, rolling and wrapping process, and carry out a systematic research on the key technologies of processing technology, research and development of typical problem equipment, and the key technologies of quality control. The key technology and quality evaluation of index system of slim cigarette processing technology and equipment needed to be established in order to improve the processing technology level and realize the high quality development of slim cigarette. [ABSTRACT FROM AUTHOR]

Cotton is an important strategic material. With the increase of cotton planting costs, improving the level of mechanized harvesting has become an important way to improve the economic benefits of cotton planting. The main cotton harvesting machinery used in China is the horizontal spindle type cotton picker. In the process of production practice, the domestic cotton pickers have problems during high-speed operation, such as improper matching of picking speed ratio coefficient, badly gear worn and poor reliability of picking head transmission system. In view of the above problems, this paper optimized the transmission system of picking head based on the comprehensively consideration of the operating speed, transmission system reliability, operation quality and other factors, aiming to increase the operating speed of the cotton picker, improve the reliability of the picking head transmission system and the operation quality of picking head. According to the structure and working principle of the horizontal spindle type cotton picking head, the transmission route and transmission ratio of picking head transmission system of cotton picker were analyzed and calculated firstly. Then, the picking mechanism and picking conditions, such as the range of picking speed ratio coefficient of cotton picker, the actual number of turns needed to pick cotton petals and the picking time of spindle, were determined through virtual simulation technology and theoretical analysis and calculation. Meanwhile, the roller power gear in the transmission system of the picking head was selected as the optimization object, the tooth number of roller power gear, modification coefficient of the upper gear on clutch, modification coefficient of roller power gear and addendum height coefficient were selected as design variables, and the objective function and constraint conditions were established. The Genetic algorithm and 1stOpt software were used to optimize the transmission system of picking head. The optimization results were as follows: the number of teeth for the roller power gear was 72, the modification coefficient of the upper gear on the clutch was -0.14, the gear modification coefficient for the roller was 1.208, and the addendum height coefficient was 1.25. A cotton picking performance test bench was built combining the operation requirements of the cotton picker. The operation performance of picking head before and after optimization was verified on the test bench with the factors as follows: picking roller speed was 113-143 r/min, the operation speed was 5.93-7.20 km/h. The results showed that the working speed of the picking head was increased from 6.4 to 7.2 km/h, increased by 3.6%, and the work efficiency increased from 4.86 to 5.47 hm²/h, increased by 12.5%. Under the working speed of 7.2 km/h, compared with before optimization, the collection rate increased from 90.4% to 93.7%, increased by 3.6%, and the impurity rate decreased from 10.28% to 9.72% and decreased by 5.4%, which verified the rationality of the optimization of the picking head transmission system in this paper. The study can provide a reference for the development of picking head of cotton picker. [ABSTRACT FROM AUTHOR]

The Gross Merchandise Volume for the China’s Singles day event in 2019 is about $38.4 billion. More than 500 million customers placed about 1.3 billion orders a day, and the related delivery volume is 2.8 billion. The main technologies associated with the 4th Industrial Revolution are bringing about a big change in the logistics industry. The purpose of this study is to present implications by reviewing the main technologies which are applied to China’s Singles day event, the introduction of smart logistics in China, and analyzing the progress of Singles day, smart system of Alibaba, its significance. China still has poor infrastructure in non-capital areas. And many Chinese companies are actively introducing and developing smart logistics to cover the vast continental area of China. Singles Day is a representative case in point where the smart logistics and main technologies related to 4th Industrial Revolution are applied. The data obtained through smart logistics would be reused for inventory management, production planning, and order processing, contributing to the optimization of the company's operations. In the era of the 4th Industrial Revolution, domestic companies and governments need to make efforts to expand the introduction of smart logistics to secure competitiveness with global advanced companies. [ABSTRACT FROM AUTHOR]

At present, the vegetable planted by seedling cultivation and transplantation accounts for more than 60% of the total vegetable planting. It has the advantages of high and stable yield, climate compensation and land use efficiency improvement. However, vegetable production belongs to labor-intensive industry, the increasingly serious problem of difficult employment leads to the fact that the labor cost of vegetable production accounts for more than 50% of the total cost of vegetable production, which has become the main factor restricting its development. Therefore, it is an inevitable trend for the sustainable development of vegetable industry to study the mechanization and automation of vegetable transplantation. Taking and dropping seedlings is a very important link in vegetable transplanting. In view of the problems of automatic transplanting of vegetable seedlings in China, such as the complex and easy to fail of seedling picking and throwing device, a kind of oblique inserting plug seedling taking and throwing device is designed in this paper. The principle of picking and seeding device was analyzed, and then the location of taking point, throwing point and any point in the process of picking seedlings were selected. The projection method was used to design the device, and the structure and working parameters were determined. The length of the frame, driven rod, connecting rod, driving rod and seedling clip were 122, 196, 80, 186 and 227 mm respectively. In order to ensure that the device has a good effect of taking and throwing seedlings, the tilt angle of the seedling tray and the parameters of the seedling clamping into the hole are designed, and the movement process is analyzed. The feasibility of the scheme is verified by comparing the simulation trace curve with the actual test trace curve. According to the mathematical model of the working process of seedling taking and throwing device, kinematics analysis and simulation are carried out, and the position of seeding taking and throwing, speed and acceleration curve of the seedling clamp endpoint are obtained, the design meets the requirements of automatic transplanting. Considering the factors affecting the effect of taking and throwing seedlings, the spring stiffness coefficient, rotational speed of the active rod and the inclination angle of the seedling tray are selected as the experimental factors, and the orthogonal experiment was carried out. The results show that the best effect is obtained when the spring stiffness coefficient is 500 N/m, the speed of the active rod is 12 r/min, and the inclination angle of the seedling tray is 45°. Repeated experiments were conducted with the optimum parameters, the results show that the broken rate of substrates is 3.13%, the expulsion rate of seedlings is 2.43%, the success rate of seedling taking and throwing is 94.44%, the reliability of the device is high. The design provides a reference for the study of full automatic transplanting. [ABSTRACT FROM AUTHOR]

In recent years, garlic planting area has become larger and larger in China, however, the level of mechanization of domestic garlic cultivation is low, at present, so all the garlic cultivation still mainly relies on manpower to complete, with low working efficiency and high labor intensity, moreover, the randomness of planting parameters is not conducive to the development of garlic mechanization. Aiming at the problem of low single seed rate in garlic mechanized planting, a claw type circulation single seed taking device was designed with the design idea of "taking more and keeping one". The dynamic model of garlic seed filling and clearing was established with discrete element technology. The internal mechanism of single seed picking was clarified through single factor simulation test. In the seed-picking process, the arc radius, center angle and lateral spacing of the middle plate of the seed taking claw were taken as the test factors, and the target rate was taken as the test index. Based on the box Behnken test design principle, the multi factor simulation test was carried out, and the parameters that affect the target rate were successively the lateral spacing of the side plate of the seed taking claw, the center angle of the middle plate and the arc radius of the middle plate. In the seed cleaning process, the inclination angle of the seed cleaning grid plate was taken as the test factors, taking the qualified rate and the missed seeding rate as the test indexes. Through the one factor test design principle, the seed cleaning performance test was carried out, and the response curve was obtained. Response curve was drawn using Design Expert 8.0.6 to investigate the effect of grid tilt angle on the response value of target rate, missing rate and replay rate, and optimize the parameters of seed selection. The response curve showed that the target rate increased first and then decreased with the increase of grid tilt angle, and the target rate reached the maximum value when the grid tilt angle was about 7°. The missing rate decreased first and then increased with the increase of grid tilt angle; the replay rate increased with the increase of grid tilt angle. The increase of gate inclination decreased first and then increased, but the increase amplitude was small. The results showed that the optimal values of the parameters were the arc radius of the middle plate was 48.52 mm, the center angle of the middle plate was 72.59%, the lateral spacing of the side plate was 25.11 mm, and the inclination angle of the grid plate was 7.41°. The predicted target rate of the model was 90.64%, the qualified rate was 92.52%, and the leakage rate was 3.30%. Laboratory and field experiments were carried out, and the experimental data were consistent with the optimization results, which provided a reference for the study of garlic mechanized seeding single seed picking technology. [ABSTRACT FROM AUTHOR]

Terrestrial biogeochemical silicon (Si) and carbon (C) cycles couple through various processes, such as silicate weathering and the dynamics resulting from different phytolith assemblages. For example, small amounts of organic C (typically ranging from 0.2 to 5.8%) can be occluded during phytolith formation. Phytoliths play an important role in coupled Si and C cycles. In this study, we analyzed variations in C sequestration and the seasonal dynamics of phytoliths formed in different vegetation types in order to clarify the processes and characteristics of phytolith-occluded-carbon (PhytOC) cycles. Firstly, we measured the variation range of phytolith content in the litter and soil of different vegetation types at 11.87–151.90 and 1.81–14.72 g kg−1, respectively, while we measured the corresponding variation range of PhytOC content at 3.58–24.13 and 0.04–0.65 g kg−1, respectively. We also found that seasonal changes in phytolith and PhytOC content were significant (P < 0.01), both exhibiting a significant decreasing trend from litter to soil and from the surface soil to 0–60 cm of soil layers. Secondly, we measured the variation range of PhytOC storage in the litter and soil (0–60 cm) of different vegetation types at 1.26–6.89 and 28.24–75.2 t, respectively. Finally, our study determined the contribution of PhytOC storage in soil (0.42%) compared with conventionally recognized soil C sequestration storage (0.64%). The phytolith C pool is an important component of the forest ecosystem C pool, which plays a critical role in mitigating global warming. [ABSTRACT FROM AUTHOR]

A problem-specific routing algorithm integrating ant colony optimization (ACO) and integer-coded genetic algorithm (GA) is developed to address the newly observed limitations imposed by ultranarrow aisles and access restriction, which exist in the largest e-commerce enterprise with self-run logistics in China. Those limitations prohibit pickers from walking through the whole aisle, and the access restriction even allows them to access the pick aisles only from specific entrances. The ant colony optimization is mainly responsible for generating the initial chromosomes for the genetic algorithm, which then searches the near-optimal solutions of picker-routing with our novel chromosome design by recording the detailed information of access modes and subaisles. To demonstrate the merits of the proposed algorithm, a comprehensive simulation for comparison is conducted with 12 warehouse layouts with real order information. The simulation results show that the proposed hybrid algorithm is superior to dedicated heuristics in terms of solution quality. The impacts of the parameters with respect to warehouse layout on the picking efficiency are analyzed as well. Setting more connect aisles and cross aisles is suggested to effectively optimize the picking-service efficiency in the presence of access limitations. [ABSTRACT FROM AUTHOR]

With the continuous development of the market economy, the tobacco industry is rapidly expanding in China. There are now numerous cigarette retailers across the country, which distribute multiple types of cigarettes to consumers in small batches and multiple times. Against this backdrop, the traditional warehouse storage and retrieval (S/R) approach, an integration of the radiofrequency identification (RFID) and manual sorting, no longer satisfies the market demand. Most cigarette distribution centres now use automated stereo warehouses, which face the complex and realistic problem of goods S/R with multiple stackers, multiple carriers and irregular goods locations. After analysing the features of the automated storage and retrieval system (AS/RS), this paper introduces the bacterial foraging optimization (BFO) algorithm to optimize the AS/RS in light of the actual work conditions. Firstly, a model framework was set up based on the production reality and algorithm constraints. Next, the model was solved by the bionic algorithm BFO. Finally, a numerical example was selected to verify the effectiveness of the algorithm. The results show that the BFO can effectively shorten the operation time and improve the S/R efficiency. The research findings provide a scientific and rational plan for automated ware-housing in complex environments. [ABSTRACT FROM AUTHOR]

Because of a regulatory policy change in February 2001, the segmentation of the Chinese stock market significantly decreased. Using this event, we show that the Chinese A-share market is more informationally efficient than the B-share market, both before and after the opening of the B-share market. Furthermore, after the event, both the adverse selection and the order-processing component of B shares decreased, as a result of a larger investor base and possibly a lower proportion of informed investors. This study thus sheds new light on the market segmentation and its effect on transaction costs. [ABSTRACT FROM AUTHOR]

The development of logistics accelerates the transportation process, which in turn increases the exchanging efficiency between cities. To understand such exchanging interactions among cities, we build a city logistics network based on a unique data set, which contains millions of online freight orders spanning a period of one year. It is found that this network exhibits a disassortative configuration and its link weight (respectively, node strength) follows a Weibull (an exponential) distribution. We also find that the hierarchical structure of the city logistics network is highly consistent with the strategic layout of constructing modern comprehensive transportation system plan in China's "Thirteenth Five-Year Plan". Furthermore, it is observed that the cities with high Gross Domestic Product (GDP) have high centrality in the city logistics network and the logistics flows between two cities are proportional to the product of their GDPs. Our results not only uncover the topological and hierarchical structure of the city logistics network in China, but also provide an understanding of the structural shaping force on the growth of city logistics network. • We construct a Chinese city logistics network based on millions of freight orders. • The network exhibits a fat-tailed degree distribution and a disassortative structure. • The cities hierarchically occupy the position in the city logistics networks. • City centrality in logistics network positively correlates with its economic status. • The logistics flows between two cities are proportional to their GDP product. [ABSTRACT FROM AUTHOR]