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In the context of the complex geological conditions such as large thickness variation of thin-medium-thick coal seam, development of strike fault and broken roof in Southwest China, intelligent fully mechanized mining support technology and equipment for thin-medium-thick coal seam are proposed. Through the implementation of grouting reinforcement and roof-lifting transformation for broken roof in the hanging wall and the footwall of fault layer, as well as the adoption of the coupled support technology of bolt-mesh-anchor combined support+advance reinforcement+blasting roof cutting+pillar hanging net gangue retaining+delayed shotcrete reinforcement+finishing wall in gob-side entry retaining, the stability of the roadway is greatly improved. A lateral self-advancing advanced support group consisting of eight advanced supports and two end supports is designed to realize the coordination and cooperation of the roof support at the end of the working face and the rapid advancement of the advanced supports. The intelligent fully mechanized mining equipment for thin-medium-thick coal seam and its optimal layout scheme are proposed. When the mining height at both ends of the working face is less than the height of the roadway, a cushion frame is used to support the head and tail of the shearer. The length of the scraper conveyor head and tail beyond the coal wall is controlled at 800 mm to ensure that the undercover amount reaches 97 mm so as to clear the floating coal in time. The scraper conveyor head is equipped with a trailer parallel to the floor, and the scraper conveyor head and tail are directly pushed as a whole through the transition support auxiliary pushing device, which effectively solves the problem of mutual interference between the rocker arm of the shearer and the scraper conveyor. The study proposes an active preventive intelligent coal cutting technology in the fault zone, which is composed of end cutting triangular coal following section process and middle oblique cutting following section process. The technology uses half cutting depth and fractional cutting methods to improve the safe coal cutting speed of the shearer under the fault zone condition.

As an important component of the cable fault detector, the output safety, stability and adjustable output range of the high voltage power supply play an important role in promoting the rapid detection of the cable fault point. In this paper, a wide range of adjustable single-stage Buck converter with rail-to-rail output characteristics is designed as a pre-regulator for the wide range of adjustable output high power supply. The closed-loop feedback compensation controller and software-configurable soft-start control method are analyzed and designed by using the unified circuit model of Buck converter. At the same time, the hardware circuit design of Buck converter based on TL494 is completed. Finally, simulation analysis and experimental test results show that this design of the Buck converter which can achieve the output voltage range from 10 to 300 V continuous adjustability has strong stability and high dynamic response. It can work continuously in 2 hours without exception.

As the main topology of high-power converter, the reliable working state of full-bridge inverter power switch plays an important role in the stable operation of the circuit. In this paper, a flyback switching power supply with 11-winding and 9-output is designed for the isolated power supply of the M57962L drive module used in the high voltage power supply IGBT full-bridge inverter main circuit. The design of flyback transformer and the second-order loop compensation network based on the three-terminal integrated voltage regulator TL431 and liner optocoupler PC817 are introduced in detail, including the selection of core, turns, diameter, primary inductance, air gap calculation and the theoretical analysis and Saber simulation analysis of the loop compensation network. Simulation and prototype test results show that the circuit design is effective. The output voltage is stable with the ripple less than 100 mV. The load regulation rate is high, and the reliability of IGBT operation is solved at the source of the driver.

Along with the rapid growth of online purchasing, more and more e-retailers tend to adopt the front warehouse mode to improve the performance of customer service by locating multiple front warehouses with limited space and storage capacity closer to consumers. In this context, order splitting and distribution become increasingly crucial decisions that might impact the efficiency of order fulfillment. These two issues are investigated in the related works commonly as two independent problems, although they are inherently coupled with each other. This study established an integrated optimization model for order splitting and distribution routing for the front warehouse mode e-retailing. The model considers practical features, including order splitting constraints based on product type and quantity, finite inventory, heterogeneous vehicle routing constraints, and time windows. A branch-price-and-cut algorithm is proposed to solve the problem. Two logic-based Benders cuts are designed to deal with the infeasible distribution routes. The efficiency of the proposed algorithm is verified in an experimental study by considering CPLEX and two heuristic algorithms as benchmark methods. The dominance of our proposed algorithm is observed, especially for large-scale cases. The impacts of overlapping inventory levels, the combination of heterogeneous vehicles, and the width of time windows are also examined. [ABSTRACT FROM AUTHOR]

Simple Summary: Coccidiosis is an intestinal parasitic disease caused by Eimeria protozoa, which endangers the health and growth of animals. However, little is known about the intestinal resident microbiota of chickens with different resistance to Eimeria tenella (E. tenella) infection and the changes in the microbiota from infection to recovery periods. The metagenomic sequencing analyses show that many potential differential microbial taxa were identified in different resistant chickens, respectively. Through the comparative analysis from infection to recovery periods, the number of microorganisms with the same trend of change between the control and resistant groups was greater than that between the control and susceptible groups. These findings provide a reference for further research into how E. tenella infection affects the intestinal microbiota and thus the growth, development, and health of chickens. To investigate the effect of Eimeria tenella (E. tenella) infection on the cecal microbiota, resistant and susceptible families were screened out based on the coccidiosis resistance evaluation indexes after E. tenella infection. Subsequently, a comparative analysis of cecal microorganisms among control, resistant, and susceptible groups as well as between different periods following the E. tenella challenge was conducted using metagenomic sequencing technology. The results showed that the abundance of opportunistic pathogens, such as Pantoea, Sporomusa, and Pasteurella in the susceptible group and Helicobacter and Sutterella in the resistant group, was significantly higher on day 27 post-inoculation (PI) (the recovery period) than on day 5 PI (the infection period). Additionally, the abundance of Alistipes, Butyricicoccus, and Eubacterium in the susceptible group and Coprococcus, Roseburia, Butyricicoccus, and Lactobacillus in the resistant group showed a significant upward trend during the infection period compared with that in the recovery period. On day 5 PI, the abundance of Faecalibacterium and Lactobacillus was decreased in both the resistant and susceptible groups when compared with that in the control group and was greater in the resistant group than in the susceptible group, while Alistipes in the susceptible group had a relatively higher abundance than that in other groups. A total of 49 biomarker taxa were identified using the linear discriminant analysis (LDA) effect size (LEfSe) method. Of these, the relative abundance of Lactobacillus aviarius, Lactobacillus salivarius, Roseburia, and Ruminococcus gauvreauii was increased in the resistant group, while Bacteroides _AGMB03916, Fusobacterium_mortiferum, Alistipes _An31A, and Alistipes _Marseille_P5061 were enriched in the susceptible group. On day 27 PI, LDA scores identified 43 biomarkers, among which the relative abundance of Elusimicrobium _An273 and Desulfovibrio _An276 was increased in the resistant group, while that of Bacteroides _43_108, Chlamydiia, Chlamydiales, and Sutterella _AM11 39 was augmented in the susceptible group. Our results indicated that E. tenella infection affects the structure of the cecal microbiota during both the challenge and recovery periods. These findings will enhance the understanding of the effects of changes in the cecal microbiota on chickens after coccidia infection and provide a reference for further research on the mechanisms underlying how the intestinal microbiota influence the growth and health of chickens. [ABSTRACT FROM AUTHOR]

Background and Aim: Refractory anastomotic leakage (RAL) after intersphincteric resection (ISR) usually leads to failure of protective stoma reversal in ultralow rectal cancers. The aim of this study is to assess the risk factors and oncological outcomes of both anastomotic leakage (AL) and RAL, and quality of life (QoL) of RAL after laparoscopic ISR (LsISR). Methods: A total of 371 ultralow rectal cancer patients with LsISR were enrolled from a tertiary colorectal surgery referral center. Risk factors for AL and RAL were identified by logistic regression. Three‐year disease‐free survival (DFS) of AL and RAL was analyzed by the Cox regression. QoL of RAL group (compared with non‐RAL group) was assessed using the European Organization for Research and Treatment of Cancer QLQ‐C30 and QLQ‐CR29 questionnaires. Results: The rates of AL and RAL after LsISR accounted for 8.4% (31/371) and 4.6% (17/371) in this cohort, respectively. Non‐left colic artery preservation (odds ratio [OR] = 3.491, P = 0.009), neoadjuvant chemoradiotherapy (nCRT) (OR = 6.038, P < 0.001), and lower anastomosis height (OR = 5.271, P = 0.010) were independent risk factors for AL, while nCRT (OR = 11.602, P < 0.001) was the only independent risk factor for RAL. Male (hazard ratio [HR] = 1.989, P = 0.014), age > 60 years (HR = 1.877, P = 0.018), and lymph node metastasis (HR = 2.125, P = 0.005) were independent risk factors of poor 3‐year DFS, but not RAL (P = 0.646). RAL patients have significantly worse global health status, worse emotional and social function scores at the late postoperative stage, and worse urinary and sexual function at the early postoperative stage (all P < 0.05). Conclusions: Neoadjuvant chemoradiotherapy was an independent risk factor for RAL after LsISR. RAL shows similar oncological outcomes, but with poor QoL. [ABSTRACT FROM AUTHOR]