Research on Design Optimization and Simulation of Regenerative Braking Control Strategy for Pure Electric Vehicle Based on EMB Systems

The benefits of electromechanical braking (EMB) systems are short response time, high braking efficiency, ease of assembly and easy integration with other electronic control systems. Therefore, a model of an EMB system is developed based on which the braking stability, braking efficiency, and the regenerative braking energy recovery in electric vehicles are investigated. Electric vehicles can effectively increase their driving range by using a rational regenerative braking control strategy. Firstly, a fuzzy regenerative braking control strategy is developed for comparison, and an optimized regenerative braking control strategy is designed based on the NSGA-II algorithm. The technique for order preference by similarity to ideal solution (TOPSIS) is used to comprehensively evaluate the Pareto optimal solution set and to select an optimal solution for the optimization problem. Secondly, a Takagi-Sugeno fuzzy neural network is trained with the optimized discrete data, and then the braking force distribution controller is obtained. Simulink and AVL CRUISE are used to simulate the control strategy. The simulation results for variable intensity braking conditions and cyclic conditions NEDC, FTP75, and CLTC-P show that the optimized control strategy outperforms the fuzzy control strategy in braking stability and braking energy recovery

Cytogenetic diversity of simple sequences repeats in morphotypes of Brassica rapa ssp. chinensis

A significant fraction of the nuclear DNA of all eukaryotes is occupied by simple sequence repeats (SSRs). Although thesis sequences have sparked great interest as a means of studying genetic variation, linkage mapping and evolution, little attention had been paid to the chromosomal distribution and cytogenetic diversity of these sequences. This paper report the long-range organization of all possible classes of mono-, di- and tri-nucleotide SSRs in Brassica rapa. Fluorescence in situ hybridization (FISH) was used to characterize the cytogenetic diversity of SSRs among morphotypes of B. rapa ssp. chinensis. The proportion of different SSR motifs varied among morphtypes of B. rapa, with trinucleotide SSRs more prevalent in the genome of B. rapa ssp. chinensis. The chromosomal characterizations of mono-, di- and tri-nucleotide repeats have been acquired. The data has revealed the non-random and motif-dependent chromosome distribution of SSRs in different morphtypes, and allowed the relative variability characterized by SSRs amount and similar chromosomal distribution in centromeric/peri-centromeric heterochromatin. The differences of SSRs in the abundance and distribution indicated the driving force of SSRs in relationship with the evolution of B. rapa species. The results provided a comprehensive view on the SSR sequence distribution and evolution for comparison among morphtypes B. rapa ssp. chinensis

Organic Geochemistry and Hydrocarbon Generation Characteristics of Shale of the Fourth Member of Yingcheng Formation in the South Shuangcheng Fault Depression, Songliao Basin

In order to evaluate the potential for oil and gas resources in the deep fault depression of the Northern Songliao Basin, shale from the fourth member of the Yingcheng Formation (K1yc4) in the South Shuangcheng Fault Depression was selected as an example. The organic geochemical characteristics such as abundance, type and maturity from experiments on low-maturity source rock samples, the hydrocarbon generation conversion rate, hydrocarbon generation amount and hydrocarbon generation period of the shale from K1yc4 were evaluated via the chemical kinetics method. The hydrocarbon generation threshold of shale from K1yc4 in the South Shuangcheng Fault Depression was analyzed by examining the organic matter (OM) in shale core samples from K1yc4. Based on the thermal simulations to an approximate buried depth of 750 m, the maximum oil-generation stage corresponds to an approximate buried depth of 1380 m. The amounts of generated oil and gas from the shale in K1yc4 are approximately 2.417 × 108 t and 0.546 × 1011 m3, respectively. The shale in K1yc4 generated crude oil mainly during the sedimentary period of the Qingshankou Formation, Yaojia Formation and Nenjiang Formation, and mainly generated natural gas during the sedimentary period of the Nenjiang Formation. In the South Shuangcheng Fault Depression, the high parts of the local structure are the favorable areas for oil and gas exploration of K1yc4 in the sag zone, which could be used for the combined production of shale oil, tight sandstone oil and conventional oil

Comparative proteomic profiles of resistant/susceptible cucumber leaves in response to downy mildew infection

Downy mildew is a serious disease in cucumber production worldwide, which is caused by Pseudoperonospora cubensis (Berk. &amp; Curt.) Rostov. Underlying the mechanism of cucumber response to downy mildew infection is important for breeding improvement and production; however, the research remains largely elusive. A comparative proteomic approach was used to reveal the differential accumulation of the proteomes from leaves of cucumber (susceptible line and resistant line) that were inoculated with P. cubensis or not by two-dimensional electrophoresis and MALDI-TOF/TOF MS. A total of 76 protein spots were successfully identified with significant changes in abundance (> 2-fold, P < 0.05) in downy mildew infected or not leaves for the susceptible line and resistant line. By the functional annotation, these proteins were classified into 8 groups including photosynthesis (29%), energy and metabolism (29%), cell rescue and defense (17%), and protein biosynthesis, folding and degradation (13%), unclassified (7%), nucleotide metabolism (3%), signal transduction (1%) and cellular process (1%). Among the 17 differentially expressed proteins between the resistant and susceptible cucumber line, most of the protein spots were concentrated in cell rescue and defense (4) and energy and metabolism (4). Moreover, a schematic diagram containing majority of the metabolic pathways of cucumber leaves in response to downy mildew was proposed. This network revealed the positive effect of several functional components in cucumber seedlings' resistant to downy mildew such as accumulation of energy supply and resistance-related proteins, hastened protein metabolism and photorespiratory, inhibited photosynthesis, and triggered photosystem repair and programmed cell death. Taken together, these results have advanced a further understanding of the key metabolic pathways of cucumber resistance to downy mildew and pathogen control in the proteomic level

Performance Parameters Optimization of a Three-Row Pneumatic Precision Metering Device for <i>Brassica chinensis</i>

To improve the problem of low seeding efficiency facing the single-row planting mode traditionally used in China, this study aimed to design a novel three-row pneumatic precision metering device. The working principle and main structure were introduced in the paper. The three main factors affecting the seeding performance comprised of vacuum pressure, angular velocity of the metering tray, and taper angle of the sucking hole. A Box-Behnken experiment design having the qualified index and missed seeding index as the experimental index was used, and the results indicated that optimal performance of the metering device was achieved when the vacuum pressure was 2.16 kPa, the angular velocity of the metering tray was 29.43 rpm, and the taper angle of the sucking hole was 61.51°. The qualified index of the inner, middle, and outer ring was 95.12%, 94.68% and 94.24% respectively, while the missed seeding index of the inner, middle, and outer ring was 3.67%, 3.12% and 2.58% respectively under the optimal combination of parameters. The bench test results were basically consistent with the optimized results. This paper can provide support for the design of a three-row pneumatic precision metering device for Brassica chinensis

Performance Parameters Optimization of a Three-Row Pneumatic Precision Metering Device for Brassica chinensis

To improve the problem of low seeding efficiency facing the single-row planting mode traditionally used in China, this study aimed to design a novel three-row pneumatic precision metering device. The working principle and main structure were introduced in the paper. The three main factors affecting the seeding performance comprised of vacuum pressure, angular velocity of the metering tray, and taper angle of the sucking hole. A Box-Behnken experiment design having the qualified index and missed seeding index as the experimental index was used, and the results indicated that optimal performance of the metering device was achieved when the vacuum pressure was 2.16 kPa, the angular velocity of the metering tray was 29.43 rpm, and the taper angle of the sucking hole was 61.51&deg;. The qualified index of the inner, middle, and outer ring was 95.12%, 94.68% and 94.24% respectively, while the missed seeding index of the inner, middle, and outer ring was 3.67%, 3.12% and 2.58% respectively under the optimal combination of parameters. The bench test results were basically consistent with the optimized results. This paper can provide support for the design of a three-row pneumatic precision metering device for Brassica chinensis

Transcriptomic and physiological analysis of atractylodes chinensis in response to drought stress reveals the putative genes related to sesquiterpenoid biosynthesis

Abstract Background Atractylodes chinensis (DC) Koidz., a dicotyledonous and hypogeal germination species, is an important medicinal plant because its rhizome is enriched in sesquiterpenes. The development and production of A. chinensis are negatively affected by drought stress, especially at the seedling stage. Understanding the molecular mechanism of A. chinensis drought stress response plays an important role in ensuring medicinal plant production and quality. In this study, A. chinensis seedlings were subjected to drought stress treatment for 0 (control), 3 (D3), and 9 days (D9). For the control, the sample was watered every two days and collected on the second morning after watering. The integration of physiological and transcriptomic analyses was carried out to investigate the effects of drought stress on A. chinensis seedlings and to reveal the molecular mechanism of its drought stress response. Results The malondialdehyde, proline, soluble sugar, and crude protein contents and antioxidative enzyme (superoxide dismutase, peroxidase, and catalase) activity were significantly increased under drought stress compared with the control. Transcriptomic analysis indicated a total of 215,665 unigenes with an average length of 759.09 bp and an N50 of 1140 bp. A total of 29,449 differentially expressed genes (DEGs) were detected between the control and D3, and 14,538 DEGs were detected between the control and D9. Under drought stress, terpenoid backbone biosynthesis had the highest number of unigenes in the metabolism of terpenoids and polyketides. To identify candidate genes involved in the sesquiterpenoid and triterpenoid biosynthetic pathways, we observed 22 unigene-encoding enzymes in the terpenoid backbone biosynthetic pathway and 15 unigene-encoding enzymes in the sesquiterpenoid and triterpenoid biosynthetic pathways under drought stress. Conclusion Our study provides transcriptome profiles and candidate genes involved in sesquiterpenoid and triterpenoid biosynthesis in A. chinensis in response to drought stress. Our results improve our understanding of how drought stress might affect sesquiterpenoid and triterpenoid biosynthetic pathways in A. chinensis

Prediction scores of postoperative liver metastasis and long‐term survival of pancreatic head cancer based on the distance between the mesenteric vessels and tumor, preoperative serum carbohydrate antigen 19‐9 level, and lymph node metastasis rate

Abstract Background The shortest distance between the superior mesenteric artery (SMA) or superior mesenteric vein (SMV) and the tumor margin was combined with preoperative serum carbohydrate antigen (CA) 19‐9 and lymph node ratio (LNR) to evaluate joint effects on long‐term survival and liver metastasis in patients with pancreatic head cancer after radical surgery. Methods This retrospective study included 149 patients who underwent pancreaticoduodenectomy for pancreatic head cancer at Harbin Medical University Tumor Hospital from May 2011 to March 2021. The preoperative serum CA 19‐9 level and LNR were combined with the SMA or SMV distance. The joint association between long‐term survival and postoperative liver metastasis was evaluated. Results Based on the receiver operating characteristic curve of postoperative liver metastasis or long‐term survival, the optimal cut‐off values of SMV distance were 3.1 and 0.7 mm, respectively, whereas the optimal cut‐off value of SMA distance was 10.25 mm. The univariate model identified the liver metastasis score (p < 0.001) as a negative factor for postoperative liver metastasis of pancreatic head carcinoma. The SMV distance (p = 0.003), SMA distance (p < 0.001), LNR score (p < 0.001), and survival score (p < 0.001) were negatively correlated with long‐term survival after pancreatic head cancer. The multivariate model highlighted SMA distance (p < 0.001), survival score (p = 0.001), and LNR score (p < 0.001) as independent risk factors for long‐term survival in pancreatic head cancer. Conclusion Liver metastasis score may be an independent predictor of postoperative liver metastasis in patients with pancreatic head cancer. Survival and LNR scores may be independent predictors of long‐term postoperative survival in patients with pancreatic head cancer. However, the LNR score appears to improve long‐term survival