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In order to reveal the aroma compositions of two varieties of Yunnan teas processed based on the Liu Bao tea craft and to explore the more suitable varieties of tea plants for making Liu Bao tea, headspace solid-phase micro extraction and gas chromatography mass spectrometry (HS-SPME-GC/MS) was used to analyze the aroma compositions of two varieties of Yunnan teas by combining the relative odor activity value (ROAV) method with the relative odor activity value (ROAV) method. Headspace solid-phase micro extraction and gas chromatography mass spectrometry (HS-SPME-GC/MS) was used to analyze the volatile constituents of the two varieties of tea from Yunnan by using the relative aroma activity value (ROAV) method. The results showed that a total of 152 volatile components were detected, with alcohols and esters as the main volatile components, and linalool, lauryl alcohol, nonanal, dihydrokiwifruit lactone, methyl linolenate and methyl palmitate as the main volatile components, and the results of ROAV showed that there were 19 main aroma-contributing volatile components during the processing of the two varieties, and the aroma compounds that were significantly (P

The high efficiency and low cost repair of perforation damage of aluminum honeycomb sandwich structure is of great significance to ensure the integrity of aviation equipment. A composite carbon fiber wet patch bonding repair process is proposed for metal panels with perforated damage in aluminum honeycomb sandwich structures. Combined with typical aluminum honeycomb sandwich structures in aircraft, intact and perforated damage samples are prepared, and composite bonding repair is carried out on perforated damage samples. A finite element simulation analysis model for four point bending strength analysis of aluminum honeycomb sandwich structure after patching and bonding repair is established, and the influence of perforation damage size on the four point bending strength of aluminum honeycomb sandwich structure and the strength recovery after repair are analyzed through simulation calculation. The results show that the bending strength of aluminum honeycomb sandwich structure can be effectively restored by using composite materials bonding method. The results of finite element simulation are in good agreement with the experimental results. The simulation model can accurately calculate the ultimate load and failure mode of all kinds of samples. The simulation results show that when the damage range is ≤φ30 mm (diameter to width ratio is less than 40%),the adhesive repair technology of composite materials can be applied to the damage repair of aluminum honeycomb sandwich structures of aircraft.

Objective In recent years, new discoveries have been made in the He 1 Member of the Hangjinqi Gas Field. And the initial gas production of some wells by fracturing can reach 10×104 m3/d, which shows that the He 1 Member has great exploration potential. However, due to the strong heterogeneity of the He 1 Member, the gas production mechanism of the He 1 Member is not clear at present, which restricts its efficient development. To accurately and quantitatively characterize the microscopic pore structure and movable fluid characteristics of tight gas sandstone reservoirs. Methods In this paper, taking the tight sandstone reservoir in the He 1 Member of the Shangshihezi Formation in the Hangjinqi Gas Field as an example, NMR and CT tests were used to study the response characteristics and fluid identification ability of different types of pores in tight sandstone. Results The research shows that the porosity of the test samples is mainly distributed in 1.7%-10%, and the gas permeability is mainly distributed in 0.1×10-3-1.4×10-3 μm2, which belongs to the typical low-porosity and low-permeability porous tight sandstone reservoir. According to the T2 relaxation time curve of the saturation component before centrifugation, the pore type of the reservoir in the He 1 Member is bimodal (mainly the left peak, the right peak is not obvious), including 3 subtypes: micropore-small pore type, small pore-mesopore type, micropore-small pore-mesopore type. The T2 relaxation time intervals corresponding to the above three subtypes of pore types are 0.1-10 ms, 1-100 ms, and 0.1-100 ms, respectively. The results of 3D CT scans show that the micropore-mesopore reservoir has the best physical properties, followed by the micropore-small pore-mesopore type, and the micropore-small pore type reservoirs have relatively poor physical properties. The T2 cut-off values of the tested samples were mainly distributed between 1 and 14 ms, with an average value of 6.11 ms. There is a certain negative correlation between the T2 cut-off value and the movable fluid percentage of the rock samples. The movable fluid porosity and permeability have a very good positive correlation, reflecting that the amount of movable fluid is significantly affected by the reservoir permeability and the number of throats. The movable water saturation in the tight sandstone reservoirs of He 1 Member in the study area is mainly distributed at 4%-9%, with an average value of 5.8%. Conclusion Overall, the original movable water saturation of the He 1 Member is low and has great development potential.

Background Birth weight is closely related to individual health. Low birth weight is a high-risk factor for early neonatal death. Macrosomia is associated with higher risk of maternal and infant complications and various chronic diseases in adulthood. Therefore, it is very important to identify the influencing factors of neonatal birth weight. Objective To investigate the relationship between maternal intestinal flora and neonatal birth weight. Methods Participants were 516 singleton mothers and their babies〔24 with low birth weight (LW group) , 479 with normal birth weight (NW group) and 13 with macrosomia (OW group) 〕 delivered at term in Guangzhou Women and Children's Medical Center from January to September 2017. Maternal intestinal flora and clinical laboratory test parameters were collected, and the composition and diversity of intestinal flora were analyzed using QIIME. LEfSe analysis was used to compare the relative abundance of intestinal flora at the genus level of the mothers of three groups of babies to identify the flora with significant intergroup differences. MaAslin was used to assess associations of maternal laboratory test parameters and microbial genera. The Boruta was used to build models for predicting three types of neonatal birth weight using maternal laboratory test parameters and intestinal flora OTUs, to assess the association of maternal intestinal floras and neonatal birth weight. Results The analysis of maternal intestinal floras showed that the abundance of Firmicutes was the highest at the phylum level, and Faecalibacterium was significantly enriched at the genus level. There were no significant differences in Simpson's Diversity Index and Shannon Diversity Index at the phylum level across the maternal intestinal floras of three groups of babies (P>0.05) . LEfSe analysis found that compared with intestinal flora of mothers of LW group, the intestinal flora of mothers of NW group showed significantly enriched Streptococcus and Roseburia (P

The architectures of publish/subscribe communication systems and various routing mechanisms and algorithms were discussed and reviewed,including the basic methods of finding communication objects,routes optimization and routes for supporting topology change and client mobile,etc; The routing methods of famous P/S systems were compared and analyzed; On the perspective of the system scalability,the direction of further research was proposed finally.

Peanut (Arachis hypogaea L.) is one of the important cash crops in China, and about 40% of peanuts are used for food production. The sucrose content was positively correlated with the flavor and taste of peanut and its products, thus increasing sucrose content in kernel was significant for the promotion of peanut quality. In this study, two F2:3 populations (NYBPXSYT5-1 and 19-1934XJHT1) were constructed to investigate the genetic model of sucrose content, and analyze the correlations between sucrose content with oil content, protein content, and other seed traits. The results showed that the sucrose contents of peanut kernel in two populations were continuously distributed and abundantly varied, and the transgressive segregation phenomenon were observed. In the two populations, sucrose content was significantly negatively correlated with oil content but significantly positively correlated with protein content. However, the correlations between sucrose content and kernel length, kernel width, and 100-kernel weight were inconsistent. The genetic analysis in two populations showed that the sucrose content in peanut kernel was mainly regulated by two pairs of main genes with the additive effect and dominant effect. There was the interaction between the two main genes, as well as the additive effect. This study initially reveals the genetic regulation of sucrose content in peanut kernels, which is beneficial for the breeding of edible peanut varieties and the cultivation of special varieties. [ABSTRACT FROM AUTHOR]

In order to effectively detect and recognize whether the personnel on the mining face in coal mines are wearing safety protection devices, a small object detection method based on improved YOLOv8n is proposed. It is applied in situations such as poor underground lighting conditions, small object sizes of safety protection device, and similar colors to the background. The method integrates Dynamic Snake Convolution (DSConv) into the C2f module of YOLOv8n backbone network to construct a C2f DSConv module, in order to enhance the model's capability to extract multi-scale features. The method introduces polarized self-attention (PSA) mechanism in the Neck layer to reduce information loss and improve feature expression capability. The method adds one detection head specifically designed for small objects at the Head layer, forming a four detection head structure to expand the detection range of the model. The experimental results show that the improved YOLOv8n model has an average precision of 98.3%, 95.8%, 89.9%, 87.2%, and 90.8% for detecting underground personnel and their safety helmets, mining lights, masks, and self rescue devices, respectively. The average precision is 92.4%, which is better than Faster R-CNN, YOLOv5s, YOLOv7, and YOLOv8n models. The detection speed reaches 208 frames per second, meeting the requirements of object detection precision and real-time performance in coal mines.

Abstract [Objective] The study aims to provide a theoretical basis for potato disease resistance breeding by investigating the characteristics of the potato defensin gene StPSK4 and conducting a functional analysis of its role in potato disease resistance. [Methods] The authors utilized bioinformatics method for a systematic analysis of StPSK4, and conduct transcriptome sequencing analysis to examine the tissue-specific expression pattern of StPSK4 under biotic and abiotic stress, assessing the plant innate immune response to Pseudomonas syringae in StPSK4 overexpressing plants. [Results] The full length CDS of StPSK4 was 457 bp, encoding 100 amino acids. StPSK4 contained a signal peptide, with its tertiary structure mainly composed of α-helices and random coils. The C-terminus of PSK4 contains the defensin sequence DYIYTQ, and the similarity between StPSK4 and Solanaceae crops was above 80%. StPSK4 was highly expressed in potato sprouts and petioles, and showed strong response to biotic and abiotic stress such as high temperature, salt, P . syringae, and Phytophthora infestans. Overexpression of StPSK4 suppressed ROS burst in potato and defensed marker gene expression, and enhanced resistance to P . syringae. [Conclusion] StPSK4 responds to various stress conditions such as high temperature and bacterial wilt infestans. Overexpression of StPSK4 inhibits ROS burst, defense marker gene expression, and resistance to bacterial wilt in potato, confirming the suppressive role of StPSK4 in potato disease resistance.

The heavy medium rapid sedimentation process is widely used in coal mining wastewater, and its process characteristics are multivariate, nonlinear and time-varying. The precision of dosing affects the effluent index and operating costs of the heavy medium rapid sedimentation process. AI artificial intelligence software, as a data science tool, replaces traditional human experience and intuition with digital technology. Compared with traditional dosing control methods, using an AI artificial intelligence dosing system can accurately adjust the dosing amount in real time based on water quantity and quality, ensuring stable effluent quality and enabling early prediction of effluent quality indicators. This project used AI artificial intelligence software to analyze data on existing heavy medium rapid sedimentation processes, identified potential correlations between data, independently created algorithm models, and validated their effectiveness, ultimately achieved the experimental goal of being applicable for guiding production. Under the same industrial control, AI artificial intelligence could save 13.5% of the dosage compared with traditional dosing, achieving energy conservation and consumption reduction. The AI artificial intelligence dosing system can perform deep learning on continuously increasing data, continuously automatically correct model parameters, and make control more accurate.

Due to the significant differences in aerodynamic loads offlaps at different positions, there are also significant differences in the loads borne by bearings at different flap angles. This leads to inconsistent wear depth of bearings at different angles. Therefore, the method of introducing uniform wear depth is difficult to apply to the dynamic characteristics analysis of flaps. To address this issue, a dynamic modeling method based on the least squares method is proposed. Firstly, based on the connection characteristics of the flap surface, the C-B method is used to make it flexible, and the RBE2 element is used to establish a rigid flexible coupling dynamic model. On this basis, combining with UAMP, DISP and UMESHMOTION subroutines, the uneven wear data of hinge bearings are obtained by using the wear evolution simulation. At the same time, the function relation among the wear depth, flap deflection angle, and friction coefficient is established via least squares fitting. Finally, the function relation is updated to the rigid-flexible coupling dynamic model by the offset of the hinge bearing center point and the friction coefficient of the ball pair, so as to obtain the dynamic response of the flap under the influence of wear, which verifies the applicability and effectiveness of the method. As wear progresses, the coaxiality of the inner and outer bearing shafts of the flaps decreases gradually, and the driving torque on the inner and outer sides increases accordingly. The maximum increase is 15.08%. This method can provide some support for designing the flap mechanism and bearing selection.

Least risk bomb location(LRBL) structure is a device for placing suspicious explosives on the aircraft.Exploring the influence of structure size and explosive location on its anti-explosion performance can provide a reference for improving the design. Based on the method of combining orthogonal experimental design with numerical simulation, the maximum strain and deformation of each dangerous part of LRBL structure are used as evaluation indicators. The range analysis method and variance analysis method are respectively used to carry out parameter sensitivity analysis on the five influencing factors of the tank wall thickness, bottom cover thickness, connection boss thickness, shear pin diameter and explosive position of LRBL structure. The results show that when the explosive equivalent is determined as 200 g, the significant degree of influence of each factor on the antiknock performance of the LRBL structure from large to small is as follows: explosive position, tank wall thickness, bottom cover thickness, boss thickness and shear pin diameter; Based on comprehensive analysis of evaluation indicators, the LRBL structural design scheme at the optimal level of each factor is obtained.

The contents of fat and sucrose are important factors to peanut quality, and revealing their hereditary properties is critical to improve the quality in peanut. In this study, the analysis of embryo, cytoplasm, and maternal effects for fat and sucrose contents in peanut seed were conducted by using general genetic model. Five peanut lines with significantly different fat and sucrose contents were selected as parents for incomplete diallel crosses. The results indicated that the fat content was mainly controlled by embryo additive effect, followed by maternal additive effect. The sucrose content was primarily governed by maternal additive effect. Correlation analysis showed that there was a significantly negative correlation between fat and sucrose contents in peanut seed (r = -0.886**), which was mostly managed by embryo additive and cytoplasmic effects. Predicted genetic effects suggested that 18-1951 with high fat content and JHT1 with high sucrose content were superior donor parents for improving the contents of fat and sucrose in peanut, respectively. [ABSTRACT FROM AUTHOR]

Due to the influence of underground coal dust and easy obstruction, the laser point cloud data of hydraulic supports is prone to be incomplete. The existing point cloud segmentation algorithms are difficult to obtain fine-grained point cloud features, unable to obtain complete structural information of the point cloud. The algorithms are prone to introducing semantically dissimilar points in the neighborhood, resulting in low precision of laser point cloud segmentation for hydraulic supports. In order to solve the above problems, a laser point cloud segmentation algorithm for hydraulic supports based on neighborhood feature encoding and optimization is proposed. The method introduces a local neighborhood feature aggregation module consisting of neighborhood feature encoding module, neighborhood feature optimization module, and hybrid pooling module. The neighborhood feature encoding module adds polar coordinate encoding and centroid offset to represent the spatial structure of local point clouds on the basis of traditional 3D coordinate encoding, improving the feature extraction capability for incomplete point clouds. The neighborhood feature optimization module optimizes the feature expression in the neighborhood space by judging the feature distance and discarding redundant features, thereby more effectively learning the local fine-grained features of the point cloud and enhancing the local contextual information of the point cloud. The hybrid pooling module combines attention pooling and max pooling to obtain single point features with rich information by aggregating salient and important features within the neighborhood, reducing information loss. A neighborhood expansion module consisting of two sets of local neighborhood feature aggregation modules and residual connections is constructed to capture long-range dependencies between features, expand the local receptive field of individual points, and aggregate more effective features. The experimental results show that the algorithm has an mean intersection over union of 93.26% and an average accuracy of 96.42% on the laser point cloud segmentation dataset of hydraulic supports. It can effectively distinguish different geometric structures of hydraulic supports and achieve accurate segmentation of various components of hydraulic supports.

【Objective】 Remote sensing has become a prominent tool for monitoring and evaluating surface water quality across catchment and basin scales. This paper compares different remote sensing technologies for assessing water quality of terrestrial rivers. 【Method】 We took the Fuyang River in Handan City as an example. Spectral data in different seasons were acquired from three distinct remote sensing platforms: Sentinel-2 satellite images, unmanned aerial vehicles (UAVs) equipped with multispectral sensors, and ASD field spectrometers. The random forest (RF) algorithm was used to derive the inversion model from each platform to assess water quality. 【Result】 ① The results obtained from RF models for different platforms showed noticeable seasonal variation. Overall, the calculated results were most accurate in the summer, followed by spring, and were least reliable in winter. During summer, remote sensing data obtained from all three platforms can accurately estimate water quality parameters. In spring, UAV remote sensing images were sufficient. ② The RF model derived from the UAV multispectral data can effectively predict turbidity (Turb) and suspended solids (SS) of water i the river, regardless of seasons. ③ The RF model derived from the hyperspectral data was most accurate for estimating total nitrogen, with R2 >0.9 in spring. ④ Hyperspectral reflectivity curves for different seasons showed distinct variation due to the change in pollution level. In summer, reflectivity distribution curves display markedly spatial variation. The reflectivity values at each wavelength varied significantly, with pronounced changes in absorption and reflection. The reflectivity curves in spring and winter were similar, but showed pronounced changes in spring, regardless of the wavelength. 【Conclusion】 Remote sensing images obtained from different platforms offer a wealth of data for river water quality monitoring. They provide a new avenue for real-time river water quality assessment.

Traditional Chinese medicine (TCM) develops rapidly in recent years in China; meanwhile, it faces new challenges and shoulders new historical missions. Moreover, the inheritance and innovation of TCM is crucial for the promotion of the Healthy China initiative. To continuously promote the high-quality development of TCM, this study analyzes the current status and development problems of TCM development from the aspects of theoretic innovation, clinical advantages and evaluation, TCM resource development and utilization, intelligent manufacturing, and globalization. Furthermore, six countermeasures are proposed. First,efforts should focus on the theoretical research of TCM, and a population-based TCM health program is suggested. Second, the existing management mechanisms and systems should be innovated, and innovation trials conducted in key evaluation systems and methods. Third, the TCM talent team construction should be strengthened to improve the clinical diagnosis and treatment levels and scientific research and development of TCM. Fourth, domestic and international resources can be integrated to stimulate the vitality of the TCM industry and promote the comprehensive development and utilization of TCM resources. Fifth, intelligent manufacturing of TCM should be emphasized, and innovative development of theoretical research, technical systems, and personnel training should be coordinated. Sixth, the globalization of TCM should be promoted to realize the integration of TCM with international traditional and modern medicine.

Novel research and development (R&D) institutions are an important organizational form of scientific and technological innovation in China. Novel R&D institutions in life sciences and medicine are oriented toward people’s life and health and play an important role in promoting the development of life sciences and medicine, forming multiple innovation subjects, and building an innovation ecology with active elements. However, their construction is still in an exploration stage, and it is urgent to optimize the construction strategy and form a stable and sustainable development capability. This study used the methods of policy research, on-site research, case study, and expert consultation to summarize the progress of policy promotion and exploration practices of novel R&D institutions in China, analyzed the construction modes and operation mechanisms of similar R&D institutions abroad, and presented challenges in the development of novel R&D institutions in the field of life sciences and medicine in China. On this basis, we proposed the following strategies for optimizing the construction of novel R&D institutions in life sciences and medicine in China: (1) building up a diversified and stable funding mechanism, (2) establishing a differentiated development path, (3) improving the recruiting and cultivating mechanism of outstanding professionals, (4) continuously innovating the organizational form of scientific research, (5) exploiting the advantages of the flexible mechanism for scientific achievement transformation, and (6) enhancing the academic influence of these institutions, thereby promoting the high-quality development of these institutions and the self-reliance and strength of China in science and technology.

In order to solve the problems of PCB image edge information missing and carrying a lot of noise in industrial production, the existing de-noising algorithm has poor effect, large amount of calculation and high complexity. Based on this, a PCB image denoising algorithm based on improved NLM is proposed to enhance the denoising quality of PCB image. Firstly, the weight adaptive algorithm based on morphology is used to enhance the PCB image, so that the PCB image retains good edge information. Secondly, the feature matching model is introduced to fuse the enhanced PCB image with the original PCB image. Finally, the PCB image is denoised by improving the weight value of NLM algorithm, and the final denoised image is obtained. Experimental results show that, compared with the existing algorithms, the proposed algorithm retains the edge information of PCB image better, has better denoising effect, significantly improves the image quality, enhances the robustness of the image, improves the calculation speed and reduces the complexity of the algorithm. [ABSTRACT FROM AUTHOR]

The deflecting to airflow flap of civil aircraft are generally driven by complex multi-hinge mechanisms in space. According to the requirements of the airworthiness clause CCAR25.671, it is necessary to carry out research on the mechanism characteristics under typical faults. Firstly, a digital prototype of the mechanism motion is constructed, and the hinge point of the rigid multi-hinge mechanism is associated with the flexible flap body by using the RBE2 unit, and the rigid-flexible coupling dynamic model of the flap mechanism is established. Then, under three aerodynamic load conditions of cruise, take-off and landing, two typical faults, hinge jamming and one-side failure of control system, are simulated by adjusting the hinge friction coefficient and setting one-side driving failure. Finally, the variation law of driving torque and hinge point load is analyzed. The results show that:when the hinge is stuck, the inner drive link ear piece is stretched and damaged; when the inner drive fails, the radial load at the hinge point of the outer rocker arm increases significantly. In practice, we should focus on the middle joint of the outer rocker arm of this type of flap. The radial and axial load-bearing capacity of the bearing avoids the situation of separate manipulation of the outer mechanism, and at the same time, it is necessary to increase the torque protection for the entire drive system.

With the development of percutaneous coronary intervention technology, acute myocardial infarction has been effectively treated, but the myocardial ischemia-reperfusion injury (MIRI) has seriously affected the prognosis of patients. During the ischemia-reperfusion period of acute myocardial infarction, oxidative stress can seriously damage cardiac function. Excessive mitochondrial reactive oxygen species (mtROS) can affect mitochondrial permeability, and cause oxidative damage of specific molecules inside the mitochondria, which is the main driving factor for MIRI. In addition, mtROS can promote the signal transduction of inflammatory after myocardial infarction, regulate myocardial cell apoptosis, and participate in myocardial remodeling after myocardial infarction. This article reviews the mechanism of mtROS production in MIRI period and the clinical value and application prospect of reducing mtROS in the treatment of myocardial infarction. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is a common primary malignant bone tumor in children and adolescents. The high recurrence and metastasis rate have become a common clinical problem to be solved, but there is no effective treatment. In recent years, studies have suggested that targeting the tumor microenvironment will likely become a new treatment direction for OS. Immune cell infiltration in the tumor microenvironment can promote tumor inflammation and angiogenesis. Tumor-associated macrophages (TAMs) are the most important immune cells in the tumor microenvironment, which play important roles in the development and metastasis of OS. The article reviews the effect of TAMs polarization on tumor cells and describes the effect of TAMs on the occurrence and development of OS from five aspects, including TAMs affecting the growth, invasion and metastasis, mediating chemotherapy resistance, stem cell-like phenotype, and immunosuppression of OS. The review summarizes the research progress of targeting TAMs in the treatment of OS in the past years, including influencing the recruitment of TAMs, promoting the polarization of M2 type to M1 type, targeting CD47 to promote the phagocytosis of TAMs, and targeting the immune checkpoint of TAMs, aiming to provide new directions and ideas for targeted therapy of OS.

BackgroundSolid-polymer electrolyte (SPE) water electrolysis has been widely used to concentrate low-level environmental tritium for measurements. It has the advantages of electrolyte elimination, infinite reduction ratio, high current, safety, and environmental friendliness. However, the use of high-activity tritium samples for the calibration of its tritium enrichment factor Et causes a tritium memory effect in the system.PurposeThis study aims to reduce the tritium contamination caused by high-activity tritium samples during calibration.MethodsFirst, the deuterium method (DM) was used to calibrate the prepared SPE-based tritium enrichment system. The strong correlation between the tritium-to-protium (β) and deuterium-to-protium separation factors (α) during the electrolysis was determined to obtain the electrolytic cell constant, k = αβ-1/βα-1. Then, based on the deuterium enrichment factor Ed, the tritium enrichment factor (Ed)k of the SPE-based tritium enrichment system was determined. Finally, the influence factors of the k-value were analyzed, and the tritium enrichment factors derived via low-level tritium measurements using the DM and spike-proxy method (SPM) were compared.ResultsThe value of k is approximately 1.088 9, with a slight variation of 0.89% among cells. The k-value depends on the electrode material, but it is almost independent of the initial volume of water.ConclusionsThe k-value can be used as a constant for calibration of the tritium enrichment factor for the same types of electrolyzer with high accuracy and precision.

Mediator is a component-based formal modeling language. With its hierarchical and modular structure, it can easily model complex systems. It takes automaton as its underlying unit. Automations are connected to form a system, which is a high-level architecture and easy to use while formalizing the model. In order to make Mediator have stronger expressive ability and formally model the system with probabilistic behavior, Mediator is extended in terms of probability, and the semantics based on Markov decision process are given to the extended language. In addition, an automatic PRISM code generation method is introduced, which can use PRISM to verify the relevant properties of Mediator models. [ABSTRACT FROM AUTHOR]

The flexibility of the power grid can be significantly promoted by the participation of power customers in dispatch. However, as the uncertainty of customer behavior,the development of demand response services is limited. To solve this problem,the framework of incentive-based demand response is constructed in this paper. The way that load aggregators integrate demand-side resources to participate in the power market is elaborated. And the behavior of power customers responding to incentive policies is transformed into demand elasticity. Then,a data-driven demand elasticity prediction method based on the integrated long short-term memory (LSTM) is proposed. Meanwhile,to improve the performance of the prediction model,the original data is smoothed and scaled,and the weight coefficients of the loss function are added. The simulation results show that,compared with the traditional LSTM algorithm and the k-proximity prediction method,the average forecasting error with the proposed model for the demand elasticity is reduced by 5.33% and 28.8%,and mean absolute percentage error (MAPE) for the total load prediction is reduced by 2.06% and 3.09%. Additionally,based on integrated LSTM,the influence of smoothing and scaling data preprocessing on prediction accuracy is analyzed. The results show that the prediction accuracy can be significantly promoted by data preprocessing.

In response to the issue of reducing satellite constellation backup costs while meeting constellation availability target,it is the hot issue in current research.In this paper,the impact of different spare strategies on the performance of a low earth orbit(LEO)satellite constellation are studied and the best spare strategy that takes into account both the performance and economic efficiency of the constellation is selected.First and foremost,a constellation availability model with degraded operation is developed.Secondly,the Markov process is used to solve this model.Last but not least,the availability of the constellation with different spare strategies at different constellation levels is calculated based on the operation data of a real LEO satellite constellation.The results show that deploying two backup satellites in each orbit can make the constellation with the lowest spare cost while meeting the availability target.The spare strategy proposed in this paper has a certain reference value for the construction of LEO satellite constellations and can provide guidance for the accurate configuration of spare satellites with reasonable cost reduction.

Aiming at the combined action effect of the corrosive environment of amphibious aircraft wading structures and random loads including water surface take-off and landing impact, based on the standard load spectrum TWIST of transport aircraft, considering the load level and frequency corresponding to the hydrodynamic load, the simulated random load spectrum of the wading structure was first compiled; the Willenborg/Chang high-load hysteresis model was used to consider the hysteretic effect of hydrodynamic high-amplitude overload on structural crack propagation, and an engineering method for damage tolerance analysis of amphibious aircraft wading structures was established. Taking the common hole edge crack of a typical wading structure of a certain type of aircraft as an example, based on the Franc3D crack propagation analysis software, the crack propagation life under the combined action of corrosive environment and random load spectrum was analyzed, and the inspection threshold value and check interval for maintaining the airworthiness of the structure were determined by residual strength analysis. The method proposed in this study is simple and feasible, and provides a theoretical basis for the damage tolerance analysis and maintenance plan formulation of amphibious aircraft wading structures.

To explore the roles of FAD2s in response to cold stress in peanut, we cloned seven AhFAD2 genes from normal oleate peanut ZH16 and high oleate peanut ZH413, respectively. The results of qRT-PCR showed that the expression patterns of FAD2 genes were similar in ZH16 and ZH413. AhFAD2-1A/B was highly expressed in flower and developing seed, AhFAD2-3A/B was mainly expressed in leaf and stem, and AhFAD2-4A/B was expressed specifically in root and flower, indicating that AhFAD2 genes played their respective roles in different developmental stages and tissues of peanut. At 6 days after inducing under 15 °C, the germination rate of ZH16 was significantly decreased while that of ZH413 was not significantly affected. The expression of both AhFAD2-1A/B and AhFAD2-4A/B were induced by cold stress. The expression of AhFAD2-1A/B was significantly up-regulated at 6 DAI in ZH16, while at 1 DAI in ZH413, suggesting that AhFAD2-1A/B was induced by cold more quickly in high oleate peanut. Furthermore, the expression of AhFAD2-4A/B was significantly up-regulated at 3 DAI in ZH16 and then decreased, while it was increased immediately and maintained at high level for six days in ZH413. Based on these results, we speculate that up-regulation of AhFAD2-4A/B may compensate the function of AhFAD2-1A/B that is deactivated under cold stress in high oleate peanut, and the deactivation of AhFAD2-1A/B is not the most important factors affecting peanut cold tolerance. This study provides a theoretical basis in breeding of high oleate peanut with high tolerance to cold stress, and the theoretical support for extension of high oleate peanut in both high latitude and high altitude regions. [ABSTRACT FROM AUTHOR]

Objective To analyze the adverse drug reaction（ADR） reports of hydroxychloroquine for clinical medication safety. Methods The ADR reports of hydroxychloroquine between May 2019 and May 2021 were analyzed. Age, reasons for drug use, time of ADR, combined drug use, and ADR outcomes were statistically analyzed. Results No severe ADR was reported. Patients over 60 years old accounted for 53.85% of the total cases, and the time of ADR appearance was significantly earlier among those under 60 years old. A total of 61.54% of ADRs were involved in multiple organs, and optic neurotoxicity was reported in 46.15% of cases. Conclusion In the treatment of oral lichen planus with hydroxychloroquine, adverse drug reactions should be monitored, and increased attention should be given to patients over 60 years old to ensure the safety of this medication.

The drooping front leading edge is a simple lifting device,which can effectively reduce the aerodynamic noise and the motion space of the mechanism. It has been applied to A380 and A350XW. In order to realize the fixing rotation of drooping leading according to given requirement,it is necessary to design a drooping front mechanism type,so a design method of hinged drooping front mechanism based on four-link is proposed in this paper. According to the design input requirements,the wire frame model of the droop leading edge mechanism is established,and the kinematics and rigid-flexible coupling dynamics simulation of the mechanism are carried out. The angle variation parameters,and driving moment and the hinge point load in the mechanism are obtained. The results show that,with the uniform rotation of the driving arm,the hinged droop front can be steadily reduced by 26°,the ratio of the maximum driving torque of the two driving planes is close to 3∶2,and the lateral load at the driving position is improved by the setting of the side strut. The design of the mechanism is reasonable,and provides a good reference for the design of modern civil aircraft.

The vibration signals of the bearings of coal mine machanical equipment under the working conditions of strong impact and heavy load show strong transient non-stationary and local nonlinear features. It is difficult to identify the fault features by the classical time-domain statistical analysis method and the global domain transformation method. The traditional order tracking method has the problems of inconvenient equipment installation and difficulty in obtaining instantaneous frequency. The traditional keyless phase order tracking method estimates the instantaneous frequency with low precision under the condition of severe speed fluctuation. This leads to poor fault identification effect. To solve these problems, a new method of bearing fault diagnosis based on harmonic matching compensation and keyless phase order tracking is proposed. Firstly, the time-frequency analysis method based on harmonic matching compensation is used to process the bearing vibration signal and estimate the instantaneous frequency accurately. Secondly, the Vold-Kalman filtering method is used to adaptively extract the harmonic component signal. Thirdly, the Hilbert transform is used to calculate the instantaneous phase of the harmonic. The mapping relationship between the time domain and angle domain is obtained, so as to complete the resampling of the original time domain signal in the angle domain. Finally, the resampled signals are processed by fast Fourier transform (FFT). The fault features of the bearing are identified by analyzing the envelope order spectrum. The simulation and experimental results show that the maximum relative error between the estimated instantaneous frequency and the actual value is less than 1%. The feature order of bearing fault is accurate and obvious, which can effectively diagnose the bearing fault.

The situation of civil aircraft structure repair process may beyond the scope of the manual,a civil aircraft structure repair plan platform based on Browser/Service(B/S)is developed in this paper,which is aim to provide the relevant reference scheme of maintenance engineers in the formulation process of structure repair process beyond the scope of the manual. Firstly,the platform requirements are analyzed from the perspective of business process and platform function. Secondly,on the basis of technologies used in the platform development,the platform design is analyzed in detail from three aspects of platform architecture,database and platform function module. Finally,the main function modules of the platform are tested through the actual operation demonstration. The results show that the platform has friendly man-machine interface,good expansibility,simple and convenient operation,can realize the electronization of civil aircraft structure damage information and repair scheme,and automatically recommend several repair schemes stored in the database according to the damage information,which provides support for the maintenance engineering department to quickly formulate the repair scheme beyond the manual.

In order to improve the comprehensive logistics support capability of domestic and foreign civil aircraft markets, and reduce the number of air materiel configuration and the cost of air materiel operation support, this paper proposes an air materiel configuration method based on air materiel sharing mode, considering the air materiel inventory and response time of each terminal. The Poisson process is used to describe the probabilities of different demand quantities of aviation materials during the study time; the aviation materials sharing group is constructed according to the transportation time relationship between the terminals; the marginal analysis method is used to expect largest number short-term aviation materials of all terminals in the sharing group to carry out air material configuration until the fleet availability needs are met, and the air material configuration technology under the sharing of air materials is realized. Studies have shown that under the specified fleet availability, the use of air material configuration technology under the condition of air material sharing can reduce the number of air materials in each terminal; the availability of the fleet can be improved under the same configuration number; The initial inventory can be maintained at a low level in the terminal group under the sharing condition. the research work has certain reference significance for improving the maintenance and support system of Chinese civil aircraft.

In order to effectively realize the dynamic time-varying reliability analysis of the radial deformation of the aero-engine low pressure compressor, based on Kriging model combined with particle swarm optimization (PSO) and extreme value idea, a particle swarm optimization extremum Kriging model (PSOEKM) method was proposed. Firstly, the analysis principle of PSOEKM method is expounded. Secondly, the modeling idea of PSOEKM method is discussed. Then, the implementation approach of time-varying reliability analysis based on PSOEKM is explored. Finally, taking the aero-engine low pressure compressor blisk as an example, the dynamic reliability analysis is carried out by using PSOEKM. The analysis results show that the reliability is 99.76% when the allowable value of radial deformation of the compressor blisk is 1.594×10-3 m. Compared with the traditional Kriging model and the extreme response surface model, the PSOEKM method has high analysis accuracy and calculation efficiency. The method presented in this paper provides a new research idea for time-varying reliability analysis of complex structures.

It is very important for the economic operation of civil aircraft to make reasonable procurement and configuration of aviation materials between multiterminals.The theoretical algorithm content formed by the research of aviation material prediction and configuration is relatively complex.In order to promote the effective application of these algorithm programs,based on the Java language,and the algorithm programs written in Matlab and Python are integrated,a multi language hybrid programming system platform for the prediction and configuration of civil aircraft is developed.Firstly,the support vector machine algorithm and marginal analysis algorithm integrated in the system platform are introdused,and the implementation of hybrid programming is described.Then,the details of the system platform design are expounded,and the implementation of hybrid programming and the conversion method of different types of programming language’s parameter are explained.Finally,the system platform functions are tested with the actual engineering data.The result shows that the platform’s human-machine interface is friendly and easy to operate,and it can better realize the functions of aviation material prediction and aviation material configuration,which can provide reference and ideas for the relevant theoretical algorithm to meet the engineering needs through platform technology.

Hinge mechanism as a widely used motion mechanism in civil aircraft,the reasonable formulation of its maintenance interval plays an important role in ensuring the safe and economic operation of aircraft.By analyzing the MSG-3,China Civil Aviation Administration and Military Standard of China,and the influencing factors of maintenance interval,the formulation process of the maintenance interval of the hinge mechanism of civil aircraft is proposed.The maintenance interval formulation of flap hinge mechanism of an aircraft is taken as an example to verify the process.The results show that the proposed process in this paper is feasible,which can provide the basis for the reasonable formulation of maintenance interval and maintenance program of aircraft hinge mechanism.The inspection threshold and repeated inspection interval of accidental damage and environmental damage of the hinge mechanism are 5 calendar years,the inspection threshold of fatigue damage is 24 000 fh and the repeated inspection interval is 14 400 fh.

it is an important link to verify and determine the candidate items of the preliminary master minimum equipment list(PMMEL)for the main civil aircraft manufacturer passing through airworthiness certification.In this paper a new PMMEL fuzzy comprehensive evaluation method of civil aircraft is proposed.Firstly,the factors domain of fuzzy comprehensive evaluation is established by analyzing the purpose of PMMEL.Then,the different fuzzy weights by using the analytic hierarchy process are determined and a fuzzy comprehensive evaluation model of PMMEL is set up.The fuzzy comprehensive evaluation results are obtained.Finally,a PMMEL candidate project of the civil aircraft main landing gear down lock spring is taken as an example.Result shows that the new PMMEL evaluation method combined with the expert-based evaluation and essential fuzzy analysis is feasible and accurate,which can accurately get the clear result of whether the candidate project is allowed to be included in PMMEL and provide the analysis result verification for the traditional PMMEL method.It has important value and bright prospects for application.

According to the requirements of AC-91-037,the item is considered to be approved by the Flight Operations Evaluation Board(FOEB)only after the proposal master minimum equipment list(PMMEL)item is validated and passed the evaluation of FOEB.In order to select suitable PMMEL items for validation,it is necessary for the main manufacturer of civil aircraft to comprehensively consider each influencing factor and conduct a scientific and effective evaluation of each factor.The PMMEL validation evaluation standard is established based on the analytic hierarchy process(AHP)in this paper.The Delphi method is used to determine the key indicators and the importance scores of each indicator.The application of evaluation standards is explained through the PMMEL items about fuel system of a certain domestic civil aircraft model,and the specific verification item is determined.The results show that the evaluation standard can evaluate PMMEL validation effectively,and provide the reference and support for PMMEL validation.

The mining of Jurassic shallow coal seam in northern Shaanxi coal base is faced with a variety of water hazards, and the traditional coal mine water hazard assessment has some limitations, so it is necessary to carry out more detailed water hazard model and zoning research in this area. Taking 3-1 coal seam of Hongliulin Coal Mine as the research object, we calculate the development height of water flowing fractured zone in coal mining, draw the contour map of development height of water flowing fractured zone, and propose the water disaster mode division method based on coal mine water disaster types by using the mutual position relationship between each aquifer and water flowing height, and divide different water disaster modes in the study area. The results show that: according to the different water filled aquifers(bodies) in the study area, the water damage types can be divided into three main water damage modes: single aquifer water damage mode, composite aquifer water damage mode and ancient Zhiluo river water damage mode. According to different water filling sources, the single aquifer water damage model can be divided into roof burnt rock water damage type and roof weathered bedrock water damage type; the composite aquifer water damage model can be divided into roof burnt rock direct-loose layer indirect water damage type, roof weathered bedrock direct-loose layer direct water damage type, roof burnt rock direct-loose layer direct water damage type and roof weathered bedrock direct-loose layer direct water damage type water damage type. The single aquifer water damage model is mainly distributed in the water flowing fracture zone, roof weathered bedrock aquifer and the area with hidden burnt rock aquifer above the mining coal seam; the composite aquifer water damage model is distributed in the water flowing fracture zone breaking through weathered bedrock aquifer, directly or indirectly affecting the loose aquifer area; the ancient Zhiluo river water damage model is distributed in the ancient Zhiluo river and the ancient river terrace. According to the analysis of the risk of water inrush under different water damage modes, the type of burning rock water damage generally does not pose a great threat to coal mining, and the risk of water inrush is small. Roof weathered bedrock water damage model, roof composite water damage model and ancient Zhiluo river water damage model are highly water-rich in some areas, and may enter the underground through the water conduction fault zone, so there is a certain risk of water inrush.

Operational consequence analysis of system failure is an important branch of aircraft operational reliability analysis, which can provide strong support for cost-benefit analysis of maintenance tasks.In order to study the impact of aircraft system failure on operational consequences and costs, this study starts with the correlation analysis of operational consequences of system failures.Firstly, the impact of aircraft system fault types and release conditions on operational consequences is analyzed.Then, combined with the current practice of airline maintenance and the idea of event tree, a method to support the evaluation of operational consequences and related costs of aircraft system failures is proposed, and the operational consequence and cost assessment model based on aircraft system failure is established.Finally, the feasibility and applicability of the proposed method are verified by taking the fuel system of a certain type of aircraft as an example.The results show that the proposed method is reasonable and effective, which can provide support for evaluating the consequences of failure operation, and provide certain reference for aircraft design, operation and maintenance.

As the material base of integrated logistic support (ILS), scientific prediction and reasonable configuration of spare parts can effectively ensure the safe and economic operation of civil aircraft. To achieve all-win results for stakeholders (manufacturers, operators, repairers, etc.), this paper conducts an investigation on the prediction and configuration management technologies for civil aircraft spare parts, and discusses its development trend in future. Firstly, the research status for the prediction technologies of civil aircraft spare parts is introduced. Secondly, the research status for the configuration management methods is explored of civil aircraft spare parts. Finally, the development trend of civil aircraft spare parts prediction and configuration management technology is studied based on the advantages and disadvantages of the existing methods. The aim of this paper is to provide a reference for the comprehensive management of domestic civil aircraft spare parts, and to improve the maintenance support system of civil aircraft.

The essence of crashworthiness is to study the protection of people（ crew and passengers）,and the head injury of the occupants accounted for a large proportion in the crash. In order to investigate the influences of different impact velocity on the occupant ’s head injury under horizontal impact conditions,a comprehensive evaluation method based on occupant ’s Abbreviated Injury Scale（ AIS） and occupant’s injury risk probability to evaluate occupant injury is proposed,and a dynamic simulation model which including seat,restraint system and dummy was constructed by LS-Dyna software. Take the typical civil aircraft double-tube triple-seat as research objects,the effects of different horizontal impact velocity（ 8. 0 m/s,10. 0 m/s,12. 0 m/s,14. 0 m/s,16. 0 m/s） on the head injury of occupants,the stages and characteristics of injuries were analyzed. The results of dummies‘ dynamic response analysis shows that occupants may be severely injured in the head and legs during the aircraft’s longitudinal impact,occupant’head injury increases rapidly with the increase of horizontal impact velocity,and occupant’fatality rate increases exponentially with increasing horizontal impact velocity,the substantial leg movement of the occupants greatly increase the risk of injuries caused by collisions with other facilities in the cabin. In addition,the dummies ’ head trajectory,the peak load of seat belt is proportional to the horizontal impact velocity. Therefore,when the crash occurs,the horizontal impact velocity should be controlled deliberately（ the fatality rate was less than 10% when the impact velocity was13. 0 m/s,and more than 80% when the impact velocity was 16. 0 m/s）.

The ultimate goal of aircraft crashworthiness design is to protecting safety for occupants. In order to more accurately simulate the dynamic response and injury of the occupants during crash event,a crash simulation model of the fuselage section which including dummy and seat restraint system was developed using LS-Dyna,and the dynamic response of the structure and occupants is analyzed in detail when the vertical impact velocity is 9. 14 m/s,the analysis includes the energy absorption characteristics and failure mode of the fuselage structure,the mooring condition of the cabin facilities,the movement and injury of the occupants,etc.,and the validity of the crash simulation model is verified by comparison simulation results with the test data.Finally,the research on the evaluation method of civil aircraft crashworthiness was carried out. Through understanding and identification of relevant airworthiness clauses,advisory circular and standards,the comprehensively evaluation method to evaluating the crashworthiness of civil aircraft was proposed based on the survival space,the strength of mooring,the injury of occupants,the evacuation channel and the post-crash environment. The crashworthiness analysis of the fuselage section shows that the injury modes of occupant in the vertical crash environment are mainly lumbar and tibia injuries,the occupant’s maximum compression lumbar load is 6. 78 k N,and the maximum axial tibia load is 7. 46 k N during the crash process. The crashworthiness of the constructed civil aircraft is systematically evaluated by the comprehensive crashworthiness evaluation method proposed in this paper,it shows that the crashworthiness of this civil aircraft is good,except for the occupant’s lumbar load slightly exceeding the airworthiness limit and requiring corresponding design improvements,the other evaluation indexes are all in accordance with the requirements.

This paper proposed a framework which attempted to incorporate articulatory information into the stochastic segment model based mandarin speech recognition system. According to the characteristics of the stochastic segment model, it used hierarchical artificial neural network to obtain the posteriors of speech signal belonging to the phonemes. Then, the posteriors were integrated into the stochastic segment model system in the first search process. Experiments conducted on "863-test" set show that about 5.93% relative improvement can be achieved in the recognition accuracy. Thus, potential of the method is demonstrated. [ABSTRACT FROM AUTHOR]

Against the dynamic complexity of the collaborative procurement influence factor in cluster supply chain, this paper adopted the method of computational experiments to simulate the formation process of collaborative procurement. It analyzed the study and interaction rules of main body in the system, quantitatively studied the influence of market demand and enterprise density and enterprise self-interest factors on the collaborative procurement of enterprises. Experimental results show that the will of enterprise who wants to choose the collaborative procurement strategy will reduce gradually as the market demand increasing; When the system reaches to steady state, the frequency of enterprises to change the collaborative procurement strategy is very low; The will of enterprise who wants to choose the collaborative procurement strategy will increase as the market demand fluctuations enhancing. And the stronger the fluctuation degree, the earlier the enterprises choose the collaborative procurement strategy. The increasing of purchasing enterprises density will result in the increasing of the number of purchasing enterprises who choose the collaborative procurement strategy. With the self-interest of purchasing enterprises increasing, more and more purchasing enterprises give up the purchasing strategy. The experimental results has a certain significance for reference in managing cluster supply chain. [ABSTRACT FROM AUTHOR]

In CSC, enterprises respond to changing market demands through dynamic matching and selection of all kinds of enterprise service resources. However, the non-equalization phenomenon is common in enterprise service matching, which not only results in a waste of service resources, but also reduces the satisfaction degree of customer needs. As a result, how to achieve the equalization based matching between enterprise services and customer demands has become a serious challenge in the field. To solve this problem, we first design an equalization based Quality of Service(QoS)model according to the operational characteristics of enterprise services. Then a complete equalization oriented service selection process is constructed, which can eliminate the non-equation phenomenon in service selection by means of adjusting the equalization based QoS model. Simulation results validate the effectiveness of the equalization based service selection method, which can improve the service utilization rate effectively without reducing the QoS of the selected services or increasing the time cost too much. [ABSTRACT FROM AUTHOR]

For the cloud service combination request from cloud consumers, the paper used the agent method and an extended contract net protocol to build a service capacity table of agent and designed a cloud service combination interaction model based on agent which was verified by simulation experiments. Experimental results show that the proposed method has higher success rate of cloud service combination than ant colony algorithm and simulated annealing genetic algorithm. [ABSTRACT FROM AUTHOR]

Against the over-constrained problem for procurer in the process of choosing supplier in cluster supply chain, this paper put forward a kind of supplier evaluation and selection model based on constraint hierarchies and fuzzy preferences. According to the necessity degree of supplier constraints for service requesters, the model divided constraints into mandatory constraint layer and non-mandatory constraint layer based on the theory of constraint hierarchies (CHs). At the same time, the model adopted the quantitative method of fuzzy preferences to ascertain the fuzzy preferences of supplier for procurer, thus simplified the process of supplier selection. In addition, the model improved the global evaluation operators of CHs and constructed a comprehensive supplier evaluation and function based on the evaluation functions of mandatory constraint layer and non-mandatory constraint layer. This comprehensive evaluation function improves the rate of the supplier selection. The effectiveness of this model is verified by an example. [ABSTRACT FROM AUTHOR]

Firstly, this paper introduced the different scheme of identity management in cyberspace. Secondly, it analyzed the current electronic identity management in cyberspace system and pointed out the hot spots in future research. Finally, it made some analyses and solutions to construct electronic identity management in cyberspace in China. [ABSTRACT FROM AUTHOR]

Howard, the great city dreamer and designer of civilization, left us not only his infinite imagination about city planning, but also rich and valuable educational legacies. His city theory includes the understanding and choice of human civilization and ethical life. He hoped that his conception of city and town could breed a new hope, new life and new civilization. Howard's city theory is strongly associated with a Utopian faith and commune complex, which contains the spirit of community education and self-governance ethics. This theory formulates a dream of an ideal city of limited scale. The ultimate goal of this dream is to build a harmonious, free and comfortable town world, where it is possible to realize the classical Greek community policy and its education plan. Howard's city planning has valuable implications for the construction of social ethics in a town and the moral education of transferred farmers. [ABSTRACT FROM AUTHOR]