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This paper presents a method to establish typical operating conditions for train traction systems by combining site-based short trip analysis with nonparametric tests, in order to overcome various obstacles, such as inadequate efficiency testing results based on rated points of train traction systems, which often fail to accurately reflect the actual energy efficiency level of systems during long-distance operation under multiple conditions, and the existing absence of typical operating conditions essential for supporting the evaluation of traction systems' energy efficiency levels and guiding the energy-saving design of products. First, short trips were categorized, screened and randomly combined. Then, the optimal short-trip combination was identified through nonparametric tests. Subsequently, the typical operating conditions were developed, taking the traction system of an electric locomotive model as a case study. Furthermore, the proposed method was verified by analyzing errors in operating characteristic parameters and assessing the similarities in velocity-force (V-F) distribution probability two-dimensional matrix. The verification results revealed a deviation between the constructed typical operating conditions and the characteristic values derived from sampled data at 4.54%, and the consistency in V-F distribution probabilities at 98.06%. These findings indicate that the method proposed in this paper accurately reflects the actual operating characteristics of train traction systems, with the established typical operating conditions closely aligning with the actual operating conditions of train traction systems, underscoring their potential for aiding in energy-saving design and energy efficiency evaluation for train traction systems.

The rapid development of electric vehicles has led to a yearly increase in charging load levels， characterized by strong randomness and unpredictability. Therefore， research on load forecasting for charging stations holds significant importance. Firstly， to address the inaccuracy of single-factor forecasting models that only consider load fluctuation trends， this paper analyzes the impact of multiple factors on the accuracy of charging station load forecasting. A load forecasting model is established that takes into account multiple influencing factors and is based on CNN-LSTM （convolutional neural network， long short-term memory）. Subsequently， given the impact of strong randomness of charging load on the model， an error correction method based on the random forest （RF） algorithm is proposed. Finally， the paper conducts simulation verification using real charging station load data as a case study. The research results indicate that the load prediction of the CNN-LSTM model， corrected by the RF algorithm， can accurately cover real values. Compared to the LSTM single model and the non-corrected CNN-LSTM model， it exhibits higher forecasting accuracy and practical value.

In order to accurately measure and analyze energy efficiency of traction systems, especially in the current absence of relevant standard references, this article presents an energy efficiency measurement system developed based on the requirements of IEC 62888-2:2018 for electric energy testing and GB/T 25117.1-2010 for torque and speed measuring instruments, taking the traction system of electric multiple units (EMUs) as the research object. To improve measurement accuracy, a purpose-made high-voltage acquisition board with isolation is designed to directly collect the output voltage signal of the 27.5 kV transformer and a pulse-type output torque-speed sensor to measure the mechanical parameters of the traction motor, enabling synchronous collection of both electrical and mechanical parameters. Through experiments conducted with standard signal sources, it is verified that the measurement accuracy of system energy consumption surpasses the standard requirement by 1.5%. Furthermore, regarding measurement of mechanical parameters, the torque accuracy exceeds the standard requirement by 0.5%, while the speed accuracy surpasses it by 0.1%. Meanwhile, in order to verify the system accuracy in dynamic energy consumption measurement, a high-precision power analyzer and this measurement system were used to simultaneously measure the energy consumption of the traction system with the same track data, revealing a relative error of less than 1%

To explore the effects of absorbed dose and particle size on enzymatic hydrolysis and fermentation of reed straws (Phragmites australias), the straws were irradiated with γ-ray irradiation at different doses (0-500 kGy) and then passed through different aperture sieves after mechanical grinding. The effects of absorbed doses and sieving aperture size on particle size distribution, comminution energy, main component content, enzymatic hydrolysis conversion rate, and ethanol conversion rate of cellulose were examined, and the optimal respective sieving aperture for reed straws with different absorbed doses were determined. The results showed that with decreasing sieve aperture size, reed straw quality decreased significantly and was negatively correlated with the absorbed dose; the comminution energy of reed straws decreased with increasing absorbed doses. With respect to consistent quality of sieved reed straws, the comminution energy increased significantly with decreasing sieving particle size. In reed straws with the same absorbed dose, the enzymatic hydrolysis conversion rate and ethanol conversion rate of cellulose increased with decreasing sieving aperture size. Compared with reed straws with particle size r ˂ 0.850 mm, the cellulose enzymatic hydrolysis conversion rates in reed straws with particle size r ˂ 0.180 mm increased by 129.20%, 85.98%, and 106.63% at absorbed doses of 0 kGy, 206 kGy, and 404 kGy, respectively, and cellulose ethanol conversion increased by 136.04%, 21.75%, and 4.39%, respectively. By compre- hensively comparing the increased ratios of comminution energy, cellulose enzymatic hydrolysis conversion rate, and cellulose ethanol conversion rate, the optimal sieving aperture of non-irradiated (0 kGy) reed straws was deter-mined to be 0.850 mm, and that of reed straws irradiated with 206 kGy or 404 kGy was determined to be 0.425 mm.

Objective To explore the effect of myofascial release technique in the treatment of stage Ⅲ lymphedema after breast cancer surgery. Methods The clinical data of breast cancer-related stage Ⅲ lymphedema patients treated in the Department of Rehabilitation Medicine of Peking Union Medical College Hospital from January 2016 to December 2021 were retrospectively collected. According to different treatment methods, the patients were divided into manual therapy group and conventional therapy group. The conventional therapy group was treated with conventional bandage compression combined with exercise training, while the manual therapy group was treated with myofascial release technique before bandage compression and exercise training. Both groups were treated 2-3 times a week, 25-30 times in total. Limb volume, pain, range of motion (ROM), and limb function were evaluated before treatment, at the end of treatment, and 3 months after treatment, with limb volume as the primary outcome index. Results A total of 79 breast cancer patients with stage Ⅲ lymphedema who met the inclusion and exclusion criteria were enrolled, including 39 in the conventional therapy group and 40 in the manual therapy group. There was no significant difference in limb volume, visual analogue scale (VAS) score, flexion and abduction ROM, and disability arm shoulder hand (DASH) score between the two groups before treatment (all P > 0.05). Compared with the conventional therapy group, the affected limb volume in the manual therapy group was reduced at the end of treatment[(2511.70±437.08)cm3 vs. (2823.58±537.60)cm3, P=0.006] and 3 months after treatment[(2492.91±446.52)cm3 vs. (2813.90±533.87)cm3, P=0.005], and VAS and DASH scores were decreased (all P < 0.05), while the anteriorflexion and abduction ROM of the affected limb were increased 3 months after treatment (all P < 0.05). Linear regression analysis showed that in the manual therapy group the mean reduction of limb volume after treatment was 156.260 cm3(95% CI: 124.264-188.255, P < 0.001) more than that in the conventional therapy group; the mean reduction of VAS score was 0.557(95% CI: 0.163-0.951, P=0.006) more than that in the conventional therapy group; and the mean reduction of DASH score was 16.590(95% CI: 12.270-20.911, P < 0.001) more than that in the conventional therapy group; the average increase of anteriorflexion ROM was 7.390(95% CI: 2.016-12.763, P=0.007) more than that in the conventional therapy group, and the average increase of abduction ROM was 12.737(95% CI: 6.320-19.153, P < 0.001) more than that in the conventional therapy group. Conclusions Myofascial relaxation may be associated with the reduction of the volume of stage Ⅲ lymphedema in patients with breast cancer. It can relieve pain and restore joint function to a certain extent.

In this study, Triarrhena lutarioriparia was irradiated by a 5 MeV electron accelerator. The effects of temperature, formic acid concentration, and absorbed dose on the separation efficiency of cellulose from Triarrhena lutarioriparia were investigated, and the separation conditions of cellulose from Triarrhena lutarioriparia were optimized by an orthogonal test. Results showed that the optimal parameters were an absorbed dose of 200 kGy, mass fraction of formic acid of 88%, oil bath temperature of 110 ℃, and reaction time of 2 h. Under these conditions, the purity of cellulose was 73.26%, and the extraction rate of cellulose was 92.99%. Under the conditions of a solid—liquid ratio of 1∶10, cellulase dosage of 15 FPU/g, enzymatic hydrolysis temperature of 50 ℃, and rotation speed of 130 r/min, an enzymatic hydrolysis reaction of Triarrhena lutarioriparia cellulose, derived from the irradiation-assisted formic acid treatment, was conducted. After 96 h, the cellulose conversion rate reached 28.43%, which was 2.43 times higher than that of the untreated raw material. Fourier transform infrared spectroscopy and X-ray diffraction showed that the structure of the separated cellulose components was intact, and the crystallinity increased significantly after treatment.

One of the most important tasks in China’s supply-side structural reform is to effectively clean up zombie firms. Using industrial firm-level data in China from 1998 to 2007, we identified zombie firms in Chinese industrial sectors. Based on the identified zombie firms, we measured the survival duration of zombie firms and empirically studied the effect of fiscal subsidies on the survival duration of zombie firms by using survival analysis. Results revealed that fiscal subsidies significantly lengthened the survival duration of zombie firms. Specifically, fiscal subsidies not only reduced the possibility of zombie firms exiting the market, but more importantly, they reduced the possibility of zombie firms’ resurrection. Thus, fiscal subsidies do not contribute to the “death” or “resurrection” of zombie firms. These results are robust despite changing the identification method and the survival analysis method, and considering the endogeneity of fiscal subsidies. Our findings show that we should adhere to market-oriented mechanism in disposing zombie firms and cut off the channels that government transfuses to zombie firms by fiscal subsidies.

Rapeseed straw was used as raw material to investigate the changes in the lignocellulosic components, types and contents of degradation products after different absorbed doses of 60Co-γ-ray irradiation, and the enzymatic hydrolysis and fermentation characteristics were evaluated in this research. The results showed that the contents of cellulose, xylan and lignin decreased, the total amount of water-soluble components increased, and the pH of water extract gradually decreased in the rapeseed straw with the increase of irradiation absorbed dose. The total amount of four types of small molecular fatty acids in the degradation products of rapeseed straw gradually increased with the irradiation absorbed dose increasing, reaching a maximum of 9.25 mg/g after 1 000 kGy irradiated. The total amount of nine types of small molecular aromatic degradation products first increased and then decreased, reaching a maximum of 0.22 mg/g in 800 kGy irradiated rapeseed straw. The cellulose conversion rate and glucose concentration of rapeseed straw by enzymatic hydrolysis increased with the increase of irradiation absorbed dose. The cellulose conversion rate decreased and the glucose concentration in enzymatic hydrolysate gradually increased with increasing substrate concentration. The cellulose conversion rate for enzymatic hydrolysis was 57.55% and ethanol conversion rate was less than 10% of 800 kGy irradiated rapeseed straw at 15% substrate concentration in separate hydrolysis and fermentation. Irradiation combined with water extraction significantly improved the enzymatic and fermentation efficiency of rapeseed straw. The cellulose conversion rate and glucose concentration for enzymatic hydrolysis were 71.62% and 40.38 mg/mL, respectively, the ethanol conversion rate was 64.00% after 48 h of separate fermentation, and the glucose in fermentation broth was completely consumed for 800 kGy irradiated rapeseed straw after water extraction at 15% substrate concentration.

The effect of 5-MeV electron accelerator irradiation of 400 kGy on the formic acid cycling separation of cellulose, lignin, and xylose from Triarrhena lutarioriparia (TL) were studied, and the enzymatic conversion rate and structural characteristics of TL cellulose were analyzed. For 400 kGy irradiated TL, the results revealed that the average purity of cellulose was 81.13% and the recovery of lignin and xylose were 28.68% and 10.16%, respectively, which were higher than those of the unirradiated sample. The recovery of cellulose, concentration of xylose, and purity of lignin increased with the increase in cycle times. The final concentration of xylose for pre- and post-irradiated TL were 31.35 mg/mL and 37.35 mg/mL, respectively, and the purity of lignin was more than 90%. Fourier transform infrared and X-ray diffraction results revealed that TL cellulose separated by formic acid were formylated and exhibited high crystallinity. The enzymatic conversion rate of TL cellulose was 54.30%–57.47% after hydrolysis for 120 h, this rate was considerably higher than that of TL. These results indicated that the formic acid recycling fractionation process could effectively separate TL lignocellulosic components, which could support its large-scale utilization.

We used 60Co-γ ray and electron beam irradiation to mutate Bacillus velezensis to breed genetically stable mutant strains. The mutant strains were screened and re-screened by plate confrontation and the four-point method to study their antibacterial effects on Colletotrichum gloeosporioides. The results demonstrated that the D10 value of Bacillus velezensis suspension irradiated by 60Co-γ ray was 2 366 Gy, and the lethality rate increased with an increase in the irradiation coefficient dose in the range of 100-2 000 Gy. The lethality rate of Bacillus velezensis was 81.8% at 2 000 Gy irradiation coefficient dose, and five mutants (B004, B112, B114, B117, and B118) were screened. The inhibition rate against Colletotrichum gloeosporioides increased from 51.2% of the original strain to 57.5%, 58.0%, 57.0%, 57.7%, and 59.9%, respectively. The Bacillus velezensis suspension was irradiated by an electron beam (10 MeV), the D10 value was 499 Gy, and the lethality rate increased with an increase in the irradiation coefficient dose in the range of 100-600 Gy. The lethality rate of Bacillus velezensis was 91.8% at 400 Gy irradiation coefficient dose. Two mutant strains (D115 and D243) were screened, and their inhibition rates against Colletotrichum gloeosporioides increased from 55.2% of the emitted strains to 58.4 and 58.1%, respectively. The inhibitory effects of B004, B112, B117, and B118 mutants on Colletotrichum gloeosporioides were genetically stable within six generations. In conclusion, γ-ray and electron beam irradiation have potential application value in the mutation breeding of Bacillus velezensis. The results provide a basis for Bacillus velezensis mutation breeding and a theoretical reference for the biological control of Colletotrichum gloeosporioides.

The study investigated the chemical composition, supramolecular structures, particle size distribution, and enzymatic efficiency of Phragmites australis lignocelluloses (PALs) with different moisture contents and treatment with 5 MeV electron beam irradiation. After irradiation, regardless of the moisture content, all PAL samples were degraded, their supramolecular structures were damaged, and the proportion of small PAL particles and the PAL enzymatic conversion rate increased significantly. There was no obvious difference in the apparent morphology, chemical structure, or crushed particle size distribution of PAL samples with different moisture contents when the absorbed dose was the same, but the enzymatic efficiency was negatively correlated with moisture content. The cellulose enzymatic conversion rates of PAL samples with 5%, 10%, and 50% moisture content were 22.24%, 19.76%, and 18.57%, respectively, and the enzymatic conversion rates of hemicellulose were 25.04%, 23.84%, and 19.56%, respectively, after 500 kGy electron beam irradiation. Meanwhile, the cellulose enzymatic conversion rates of PAL with 5%, 10%, and 50% moisture content were 54.09%, 47.27%, and 49.24%, respectively, and the enzymatic conversion rates of hemicellulose were 62.30%, 53.25%, and 47.83%, respectively, after 1 000 kGy electron beam irradiation. When the absorbed dose was 500 kGy, PAL cellulose and hemicellulose samples with 5% moisture content were severely degraded compared to samples with 10% and 50%. Meanwhile, when the absorbed dose was 1 000 kGy, the PAL cellulose and hemicellulose samples with 50% moisture content were severely degraded compared to those with 5% and 10% moisture content. Moreover, more cellulose and hemicellulose with 50% moisture content in PAL were degraded to non-carbohydrate substances compared to those with 5% and 10% moisture content.

The quality of Tungsten Inert Gas welding is dependent on human supervision, which can’t suitable for automation. This study designed a model for assessing the tungsten inert gas welding quality with the potential of application in real-time. The model used the K-Nearest Neighborhood (KNN) algorithm, paired with images in the visible spectrum formed by high dynamic range camera. Firstly, projecting the image of weld defects in the training set into a two-dimensional space using multidimensional scaling (MDS), so similar weld defects was aggregated into blocks and distributed in hash, and among different weld defects has overlap. Secondly, establishing models including the KNN, CNN, SVM, CART and NB classification, to classify and recognize the weld defect images. The results show that the KNN model is the best, which has the recognition accuracy of 98%, and the average time of recognizing a single image of 33ms, and suitable for common hardware devices. It can be applied to the image recognition system of automatic welding robot to improve the intelligent level of welding robot.

Taking the dynamic time series data of gas emission in mining face as the research object, the early warning model of coal and gas outburst was established based on single-time gas emission information function. Based on the data of 21118 heading face before outburst of Panyi Mine in Huainan, the single-time gas emission information function diagram was drawn, named as G-line diagram in short. The result showed that during normal production period, the entity of G-line diagram was small, which was close to a stable horizontal line. And before the outburst, the G-line diagram showed an upward trend. The negative and positive entity of G-line diagram became larger. At the same time, there were many times positive lines in the process of rising. According to the different shape, colour, length and other characteristics of G-line diagram, the change trend of coal body state in front of working face can be judged. Based on that, the outburst symptoms in the incubation stage of coal and gas outburst can be identified, and the early warning of outburst can be realized. It is of great significance to ensure the safety of mine production.

The exploration of marine controlled source electromagnetic survey for gas hydrate generally consists of a dynamic horizontal electric dipole source towed in the sea water and a static receiver array allocated on the seafloor. In this paper, two orthogonal horizontal components of electric field excited by a horizontal electric dipole source upon one-dimensional horizontal-layered seafloor are calculated to study the effect of different arrangements and gas hydrate models on the response of electric field. There are several dominant factors determining the variation of induced field, including transmitting frequency of the source, distance between the source and the seafloor, water depth, thickness of the overburden layer, as well as physical and chemical structure of the gas hydrate model. Modeling results suggest that the amplitude of received electric fields can reach up to 10-16–10-10 V /(A·m2) by adjusting transmitting frequency; keeping the source being towed several tens of meters above the seafloor can improve the survey efficiency but not decrease the quality of collected data; deep water environment and shallow thin overburden layer are favorable for the survey because of their attribution to signal-to-noise ratio; the porosity and saturation of gas hydrate have significant influence on medium resistivity-the higher resistivity the medium has, the bigger the amplitude of electric field response will be. Forward modeling can provide valuable information for the development of instruments and the design of survey to detect gas hydrate. 摘 要: 海底天然气水合物电磁勘探采用动态水平电偶源发射与静态阵列式海底偶极接收的测量方式。基于一维地电模型，求解海底水平层状介质的电偶源电场响应，得到海底两个水平正交电场的传播表达式，据此研究天然气水合物电场响应的影响因素。对供电频率、电偶源离地高度、海水深度、覆盖层厚度以及天然气水合物地层自身的物理化学结构等因素与归一化电场幅值的关系分别进行了计算分析，结果显示：调整供电频率可使归一化电场幅值变化于10－16～10－10 V/(A·m2)；将电偶源施放至离海底数十米高度进行拖曳可获得较好的作业效果，且不改变信号采集的质量；深水及浅薄覆盖层属于有利的探测环境，该环境下的感应场源具有较高的信噪比；天然气水合物的孔隙度、饱和度影响介质电阻率值，其电阻率越高，电场响应幅值越大。正演模拟结果可对天然气水合物探测设备研制及海洋作业提出切实可行的设计方案。图7参22 Key words: marine exploration, controlled source electromagnetic method, gas hydrate, electric field response, forward modeling

There has been considerable development of seismic detectors over the last 80 years. However, there is still a need to further develop new earthquake exploration and data acquisition systems with high precision. In particular, for China to keep up with the latest technology of these systems, it is important to be involved in the research and development, instead of importing systems that soon fall behind the latest technology. In this study, the features of system-on-a-programmable-chip (SoPC) technology are analyzed and used to design a new digital seismic-data acquisition station. The hardware circuit of the station was developed, and the analog board and the main control data-transmission board were designed according to the needs of digital seismic-data acquisition stations. High-definition analog-to-digital converter sequential digital filter technology of the station (cascade integrator comb filter, finite impulse response digital filter) were incorporated to provide advantages to the acquisition station, such as high definition, large dynamic scope, and low noise. A specific data-transmission protocol was designed for the station, which ensured a transmission speed of 16 Mbps along a 55-m wire with low power consumption. Synchronic acquisition was researched and developed, so as to achieve accuracy better than 200 ns. The key technologies were integrated into the SoPC of the main control data-transmission board, so as to ensure high-resolution acquisition of the station, while improving the accuracy of the synchronic acquisition and data-transmission speed, lowering the power consumption, and preparing for the follow-up efforts to tape out.