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With the continuous increase in the installed capacity of gas turbine units， the coupling between electric grids and gas networks has become increasingly tight， forming an integrated electricity-gas system （IEGS）. As the proportion of renewable energy generation continues to rise and the discrepancy between peak and off-peak loads widens， the supply-demand imbalance in the IEGS becomes more severe. Therefore， the economic dispatch model of a two-stage IEGS considering the flexibility of gas turbine units is constructed. Firstly， given the constraints of gas network pressure on line pack， this paper proposes a flexibility evaluation model for gas turbine units that takes into consideration the impact of the natural gas system. It also establishes a modulation range index for the gas turbine units to assess their maximum adjustability. Then， the maximum adjustability of the gas turbine units is incorporated into the output constraints of the gas turbines in the power system. Based on the power system dispatch model， the paper aims to minimize the total operational cost. Lastly， the effectiveness of the proposed model is verified using the IEEE 39-node power system and Belgium 20-node natural gas system.

Background With the increasing of older adults with disability, it is urgent to understand the disability status of older adults in different settings and to improve the long-term care service model from professional institutions to communities and families. Objective To investigate the disability status of older adults in different settings (hospitals, nursing facilities, and communities) , compare and analyze the differences in the disability status of the elderly in different settings. Methods The multi-stage sampling method was used in this study from January 2022 to January 2023. At the first stage, one or two provinces were conveniently selected in East China, South China, Central China, North China, and Southwest China; at the second stage, 3 tertiary hospitals, 2 secondary hospitals, 2 community health centers, and 1 nursing facility were conveniently selected as the study sites in each province. Older adults in 27 tertiary hospitals, 18 secondary hospitals, 18 community health service centers, and 9 nursing facilities in 9 provinces and cities (Beijing, Hunan, Jiangsu, Guangdong, Fujian, Xinjiang Uygur Autonomous Region, Guizhou, Hainan, and Sichuan) were finally included as study subjects. Barthel Index (BI) was used to evaluate basic activity of daily living (BADL) . Lawton-Brody Instrumental Activity of Daily Living scale was used to evaluate instrumental activity of daily living (IADL) . The Logistic regression analysis was used to explore the association of settings with BADL disability degree, IADL disability degree and functional disability in different aspects for older adults. Results A total of 27 344 questionnaires were collected and 23 922 were valid, with a valid recovery rate of 87.5%. There were 10 318 cases (43.1%) disabled in BADL, and the top three disabled BADL functions were bed-chair transfers, ascend and descend stairs, mobility on level surfaces. The incidence of BADL disability in various places was 29.0% in communities, 74.9% in elderly care institutions, 54.0% in secondary hospitals, and 44.6% in tertiary hospitals. Besides, 19 200 (80.3%) cases were disabled in IADL and the top three disabled IADL functions were mode of transportation, housekeeping and shopping. The incidence of IADL disability in various places was 74.6% in communities, 96.4% in elderly care institutions, 83.6% in secondary hospitals, and 81.1% in tertiary hospitals. Different settings were the influencing factor for the disability degree and functional disability types (P

Subjective interference is a common difficulty in vocal music teaching, and human ear audition cannot fully objectively analyze the students’ problems in vocal practice due to the influence of environment and other factors. This paper takes the convolutional neural network as the vocal music recognition algorithm and the Mel spectrum as the vocal music feature extraction algorithm and constructs the vocal music analysis model based on the optimization and improvement of the two algorithms. Then select the support vector machine, the nearest neighbor node, Wavenet, LSTM, GAN, SAGAN, CLDNN_BILSTM, and other models, as well as this paper’s model, for comparison experiments. Finally, the model was utilized in the vocal education classroom to evaluate the singing practice of four students. It is found that the MSE value of Arousal’s algorithm in this paper is the lowest, and the R2 values of 0.51197 and 0.71058 are the highest in the test of the MFCC vocal music feature dataset. Valence’s model in this paper has the MSE value of 0.51996, which is still the lowest, and the R² value of 0.76946, which is still the highest. This paper’s model has the best performance and results. The average rate of professional singers is 61 beats, and the model calculates the average singing rate of the four students as 77, 66, 63, and 61 beats. The first three still have a large gap compared to the standard level, and the student D level is higher. The problem of student practice analysis and vocal feature extraction and recognition in vocal teaching can be solved using new ideas and methods provided in this study.

Objective: In order to improve the accuracy and operating efficiency of the egg crack detection method based on computer vision. Methods: Used poultry egg simulation impact equipment to obtain cracked eggs, and collected images of cracked eggs and intact eggs from different angles through egg dynamic image acquisition equipment. Then, the YOLO-v5, ResNet and SuffleNet models for cracked egg image recognition were established for the original and the preprocessed egg images, respectively. After that, the recognition accuracy and the adaptability for original egg images recognition of different models were compared. Results: The YOLO-v5, ResNet and SuffleNet models could effectively identify the preprocessed cracked egg images, and the accuracy rates of verification set were 98.8%, 97.8% and 99.4% respectively. For original eggs images, the ResNet model had a low recognition accuracy, while the SuffleNet model had the highest recognition accuracy, which was up to 99%. Conclusion: Among the convolutional neural network models, SuffleNet model is most suitable for cracked egg image recognition, and the egg image preprocess is not necessary. This study provides a reference for the further improvement of crack egg detection methods based on computer vision.

This study aimed to develop an ultraminiature pressure sensor array to measure the force exerted on teeth. Orthodontic force plays an important role in effective, rapid, and safe tooth movement. However, owing to the lack of an adequate tool to measure the orthodontic force in vivo, it remains challenging to determine the best orthodontic loading in clinical and basic research. In this study, a three-dimensional (3D) orthodontic force detection system based on piezoresistive absolute pressure sensors was designed. The 3D force sensing array was constructed using five pressure sensors on a single chip. The size of the sensor array was only 4.1 × 2.6 mm, which can be placed within the bracket base area. Based on the barometric calibration, conversion formulas for the output voltage and pressure of the five channels were constructed. Subsequently, a 3D linear mechanical simulation model of the voltage and stress distribution was established using 312 tests of the applied force in 13 operating modes. Finally, the output voltage was first converted to pressure and then to the resultant force. The 3D force-detection chip was then tested to verify the accuracy of force measurement on the teeth. Based on the test results, the average output force error was only 0.0025 N (0.7169%) (p = 0.958), and the average spatial positioning error was only 0.058 mm (p = 0.872) on the X-axis and 0.050 mm (p = 0.837) on the Y-axis. The simulation results were highly consistent with the actual force applied (intraclass correlation efficient (ICC): 0.997–1.000; p

Aiming at the problems existing in the current mechanisms of delay guarantee in wireless networks(i.e. poor scalability, coarse granularity for provided service levels, and improving delay performance at the expense of sacrificing some resource utilization), this paper puts forward both the idea of particle access and the corresponding access mechanism. In this paper, a traffic flow is modeled as a group of information particles that carry a certain amount of information and are valid for certain periods of time. Firstly, the definitions of information particles and the group of information particles are given. It is proved that the minimum reachable access bandwidth of an information particle group can be achieved by using the EDF(earliest deadline first) transmission strategy. Moreover, a fine-grained mechanism of delay guarantee based on the idea of particle access is proposed for the dynamic access environment in wireless networks. Extensive simulations are carried out for the application scenario of downlink transmissions, and it is shown that, in the case of heavy traffic loads, comparing with the rapid growth of the average packet delays and the packet loss rates in a legacy access mechanism, the proposed fine-grained access strategy based on the idea of particle access can also achieve the better performance on the average packet delays and the packet loss rates, and hence higher effective throughput is obtained. The research in this paper pave a new way for further improving quality of service (QoS) mechanisms of wireless networks.

Lumbar plexus block is often used as analgesia for adult hip surgery, but it is rarely used in pediatric patients. This study aimed to compare the efficacy and feasibility of ultrasound-guided lumbar plexus block versus transversus abdominis plane block for postoperative analgesia in children with hip dislocation. Eighty children undergoing unilateral hip dislocation surgeries at our hospital from October 2019 to February 2021 were randomized to the lumbar plexus block group (group L) and transversus abdominis plane block group (group T). Compared with group L, the regional block time in group T was lower (8.0 ± 2.5 vs 11.5 ± 2.3 min, P < 0.05), and the ultrasound image definition was better (P < 0.05). There were no significant differences in mean blood pressure and heart rate within 24 h (all P > 0.05). Children’s Hospital of Eastern Ontario Pain Scale scores were lower in group L than in group T at 18–24 h only (all P < 0.05). The satisfying analgesia rate in group L was higher than in group T (87.5 vs 65%, P < 0.05). No regional block-related complications were found in both groups. Ultrasound-guided lumbar plexus block showed a longer postoperative analgesic effect in children with hip dislocation compared with transversus abdominis plane block.

The electric power system has made a great contribution in the process of promoting common prosperity in China, but the current electricity regulatory system has weakened the full play of the function of supporting common prosperity in some aspects, including: rural residents have a heavy economic burden of electricity consumption, and some rural poor people still face “power poverty”; Underdeveloped areas subsidize developed areas in reverse, while developed areas often face the livelihood problems of power shortage; The contradiction of the existing electricity price cross-subsidy mechanism is becoming more and more prominent, and high-income groups enjoy more cross-subsidies. In view of the above problems, we put forward the following three suggestions: Exempt rural low-and middle-income residents from electricity charges by quota, and to support urban and rural residents to enjoy power public services more equally; Accelerate the marketization process of power generation resources and power pricing, and promote regional balanced development based on the comparative advantages of power resources; Add a higher-level residential electricity price ladder and promote cross-subsidies within residents to replace cross-subsidies between departments.

【Objective】 Water pollution is a great environmental concern for surface water in many regions in northern China, and how to purify the water is essential to maintaining its ecological function. The aim of this paper is to test the feasibility of different biotechnologies for water purification. 【Method】 The experiments were conducted in the northern section of the great Canal in Tianjian, in which we investigated the efficiency of four aquatic plants in comparison with artificial aquatic plants, aeration-aquatic plants-artificial aquatic plants. 【Result】 The removal effect of the bioecological combined technology was better than that of the artificial aquatic plants, aquatic plants and other technologies. After running for 10 months, the purification site build 1.1km downstream of the outlet of the seventh sewage treatment plant at Wuqing has seen the NH4+-N and TP reaching Standard V for surface water, with the floating beds reducing NH4+-N and TP to 0.36 kg/m2 and 0.073 kg/m2, respectively. 【Conclusion】 The bioecological combination technology facilitated the removal of nitrogen and phosphorus in the water during both winter and summer, especially in winter. It overcomes the disadvantages of plant wilt and poor removal effect, and realizes the effective purification of NH4+-N and TP in low temperature environments, suitable for the application of water quality improvement and landscape restoration in north slow river.

Objective: Liquid-liquid phase separation (LLPS) is a functional unit formed by specific molecules. It lacks a membrane and has been reported to play a crucial role in tumor drug resistance and growth by regulating gene expression and drug distribution. However, whether LLPS could be used to predict cancer prognosis was not clear. This study aimed to construct a prognostic model for breast cancer based on LLPS-correlated genes (LCGs).Methods: LCGs were identified using the PhaSepDB, gene expression profile and clinical characteristics of breast cancer were obtained from TCGA and cBioportal. The PanCancer Atlas (TCGA) cohort was used as the training cohort to construct the prognostic model, while the Nature 2012 and Nat Commun 2016 (TCGA) cohort and GEO data were used as test cohort to perform external verification. Data analysis was performed with R4.2.0 and SPSS20.0.Results: We identified 140 prognosis-related LCGs (pLCGs) (p< 0.01) in all cohorts, 240 pLCGs (p< 0.01) in the luminal cohort, and 28 pLCGs (p< 0.05) in the triple-negative breast cancer (TNBC) cohort. Twelve genes in all cohorts (training cohort: 5/10-year ROC values were 0.76 and 0.77; verification cohort: 5/10-year ROC values were 0.61 and 0.58), eight genes in the luminal cohort (training cohort: 5/10-year ROC values were 0.79 and 0.75; verification cohort: 5/10-year ROC values were 0.62 and 0.62), and four genes in the TNBC cohort (training cohort: 5/10-year ROC values were 0.73 and 0.79; verification cohort: 5/10-year ROC values were 0.55 and 0.54) were screened out to construct the prognostic prediction model. The 17-gene risk-score was constructed in all cohorts (1/3/5-year ROC values were 0.88, 0.83, and 0.81), and the 11-gene risk-score was constructed in the luminal cohort (1/3/5-year ROC values were 0.67, 0.85 and 0.84), and the six-gene risk-score was constructed in the TNBC cohort (1/3/5-year ROC value were 0.87, 0.88 and 0.81). Finally, the risk-score and clinical factors were applied to construct nomograms in all cohorts (1/3/5-year ROC values were 0.89, 0.79 and 0.75, C-index = 0.784), in the luminal cohort (1/3/5-year ROC values were 0.84, 0.83 and 0.85, C-index = 0.803), and in the TNBC cohort (1/3/5-year ROC values were 0.95, 0.84 and 0.77, C-index = 0.847).Discussion: This study explored the roles of LCGs in the prediction of breast cancer prognosis.

To further improve the thermal efficiency of diesel engines, a waste heat recovery system model utilizing organic Rankine cycle (ORC) is constructed and verified through system bench test and heat exchanger bench test. To recover waste heat from diesel engine exhaust, ethanol, cyclopentane, cyclohexane, R1233zd (E), and R245fa were selected for comparison. The quality of heat source, the quality of evaporator, the system output, and the system complicity were taken as variables for comparison. Analysis shows that for ORC systems without recuperator, ethanol system has the best system output of the five in a wide operation temper range, with the highest exergy efficiency of 24.1%, yet the exergy efficiency increase after the application of recuperator, 9.0%, is limited. For low temperature exhaust, cyclopentane system has the best performance with or without recuperator, and the cyclopentane system with recuperator has the best performance in terms of exergy efficiency, 27.6%, though complex heat exchangers are also required for high power output. The system output of the R1233zd system is better than the R245fa system, yet the advantage of low evaporate temperature can be better utilized for low quality waste heat recovery.

The increasing demand of cooling in internal combustion engine (ICE) may require the shift of heat removal method from traditional single phase liquid convection to subcooled flow boiling in order to fulfill the desired functional temperature. Thus, the characteristics of subcooled flow boiling heat transfer should be studied exclusively considering the practical conditions in ICEs. Accordingly, in this article, subcooled flow boiling experiments were conducted in a rectangular channel using 50/50 volume mixture of ethylene glycol and water coolant (EG/W) as working fluid. Aluminum and cast iron surfaces were selected as the heated surfaces to simulate the material of cylinder head in gasoline and diesel engines, respectively. Experimental results showed a trend that the aluminum surface had a better performance than the cast iron surface in terms of heat transfer coefficient in the boiling region. The difference between these two surfaces was concluded as results of different surface thermophysical properties. A modified wall heat flux model was proposed based on the power-type addition method. The proposed model modified the nucleation boiling contribution by introducing a new parameter which accounts for the influence of thermophysical properties of heated surface on the boiling process. Thus, one such modified model could be useful for practical engine cooling applications.

C30H48O4, orthorhombic, P212121 (no. 19), a = 12.34133(14) Å, b = 16.50759(15) Å, c = 26.8804(2) Å, V = 5476.23(9) Å3, Z = 8, Rgt(F) = 0.0422, wRref(F2) = 0.0990, T = 293 K.

The inflow uniformity before selective catalytic reduction (SCR) catalyst carrier is a major issue for DeNOx capability of diesel engine after-treatment. Through the construction of the numerical model and CFD simulation of six perforated plate variations with different structural and positional characteristics, the influence of perforated plates on the uniformity of the airflow velocity at the inlet of the SCR catalyst carrier was analyzed. Comparison of different perforated plate variations shows that the encircling flow is a major hindrance to achieve higher inflow uniformity. Enclosed flow passage can remove the encircling flow and increase inflow uniformity at the cost of increased pressure drop. Rational layout of the perforated plate can achieve uniformity increase, while decrease pressure drop. High-velocity exhaust coupled with larger holes can improve both uniformity and pressure drop. The uniformity index increased from 97.6% of the original design to 98.7% of the optimized design, while pressure drop increased from 11.20 to 12.09 kPa. Weighing the relationship between inflow uniformity and pressure drop is an issue worthy of attention.

C31H48O5, monoclinic, P21 (no. 4), a = 11.0421(3) Å, b = 6.49710(16) Å, c = 20.4687(4) Å, β = 97.922(2)°, V = 1454.45(6) Å3, Z = 2, Rgt(F) = 0.0382, wRref(F2) = 0.1024, T = 293(2) K.

Objective To investigate the expression levels of calcium net protein (CRT) and CD47 in gastric cancer tissues and its relationship with clinical parameters, to explore the significance of CRT and CD47 in gastric cancer tissues. Methods We collected the pathological specimens and clinical data of 50 patients undergoing radical gastrectomy in our hospital. At the same time, the corresponding normal tissues were collected as control group. Immunohistochemical method was used to detect the expression of CRT and CD47. We analyzed the difference of CRT and CD47 expression between gastric cancer and paracancerous tissues and their relationship with age, sex, tumor size, lymph node metastasis, tumor differentiation and tumor invasion depth (T stage). Kaplan-Meier curve was used to analyze the 3-year overall survival rate after radical resection of gastric cancer. Results The expression rates of CRT and CD47 in gastric cancer tissues were 68.0% and 56.0% respectively, significantly higher than those in adjacent normal tissues. The expression levels of CRT and CD47 were related to the differentiation degree, lymph node metastasis and tumor invasion. The survival time of high CRT and CD47 expression group was shorter than that in low expression group (P < 0.05). Conclusion CRT and CD47 are potential markers of gastric cancer, which may provide potential targets for the early diagnosis and immunotherapy of gastric cancer.

Typical tripod foundations are designed using deterministic computational models according to relevant standards and codes. However, for more cost-safety balanced design, uncertainties in significant parameters should be considered in preliminary design to ensure meeting a specific probabilistic safety target in the context of the complex configuration of a tripod structure. In this article, uncertainties associated with design parameters and modelling errors are considered using Monte Carlo simulations, in order to determine the key structural design parameters, and to determine the optimal balance between design parameters and design requirements. A Spearman rank-order correlation based analysis is carried out to understand the effects of design variables on maximum deformation, total weight, and natural frequency, and to have insight about important design parameters for improvement of a preliminary design. It is found that the tower diameter has the most significant effect on the maximum displacement on the hub as validated through engineering case studies. In addition, a statistical framework, which identifies influential design parameters and provides reliability evaluation, is proposed for the structural design of a tripod OWT system. The design cases considered in this study indicate that a simple deterministic design check cannot guarantee the required reliability level of the structure, and the cost-safety balance can be achieved by a reliability analysis with the consideration of the uncertainties in the structure.

In order to guide the design,type selection and operation of variable speed permanent magnetic coupler for mine,finite element method is used to simulate electromagnetic field of the coupler. The influence of three key factors air-gap thickness,conductor plate conductivity and conductor plate thickness on three important performance indexes the maximum transmission torque,the maximum adjustable speed and the power loss were analysed. then the analysis results were applied to load matching.The analysis results obtained the correlation between three factors and three performance indexes. For constant torque,permanent magnet coupling has a maximum speed range of 13%; but it has no energy-saving effect,and for quadratic law load,it could reduce 13% of flow and has up to 34% energy savings.

In view of problems of long time consumption and electric leakage of traditional charging modes for mine-used electric locomotive, a wireless charging system for mine-used electric locomotive based on loose coupling transformer was proposed. Effects of iron core matching deviation on loose coupling transformer efficiency were simulated by use of finite element software ANSYS Maxwell, and simulation results were verified through experiments. The simulation and experimental results show that transformer efficiency increases with decrease of air gap, and changes little within 50 mm of transverse displacement deviation and 40 mm of longitudinal displacement deviation.

Liquid unloading is a very common and important issue in horizontal gas wells, and the presence of curve sections increases the complexity of the phenomenon and its study. Liquid loading in a gas well will sharply reduce production, therefore, the liquid-unloading onset of different curved pipes is essential to gas production. In this work, liquid-unloading onset experiments were conducted in curved pipes with different curvatures. Then, the critical gas velocity VsgCR can be determined according to the measured pressure gradients, liquid holdup, and liquid film reversal. This work analyzes the factors which will lead to the liquid unloading and explores the trend of the pipe curvature’s influence on the liquid unloading under laboratory conditions. The experimental results show that the critical gas velocity rises with the increase of pipe curvature, the increase is mainly due to the centrifugal force. The present work also compares the predicted results of the OLGA model and Beggs–Brill model with experimental data. The comparison results indicate that both models fit relatively well to the experimental data at the low superficial gas velocity, and both models have poor performance at high superficial gas velocity. The OLGA model fits the experimental data better than the Beggs–Brill model at high superficial gas velocity. The error analysis shows that most of the predicted data is not in good agreement with experimental data. Some errors between experimental data and calculation results are out of the range of 50%.

Because face images are naturally two-dimensional data, there have been several 2D feature extraction methods to deal with facial images while there are few 2D effective classifiers. Meanwhile, there is an increasing interest in the multilinear subspace analysis and many methods have been proposed to operate directly on these tensorial data during the past several years. One of these popular unsupervised multilinear algorithms is Multilinear Principal Component Analysis (MPCA) while another of the supervised multilinear algorithm is Multilinear Discriminant Analysis (MDA). Then a MPCA+MDA method has been introduced to deal with the tensorial signal. However, due to the no convergence of MDA, it is difficult for MPCA+MDA to obtain a precise result. Hence, to overcome this limitation, a new MPCA plus General Tensor Discriminant Analysis (GTDA) solution with well convergence is presented for tensorial face images feature extraction in this paper. Several experiments are carried out to evaluate the performance of MPCA+GTDA on different databases and the results show that this method has the potential to achieve comparative effect as MPCA+MDA.

Since three-dimensional image measurement allows object surface shapes and dimensions to be obtained quickly and without any contact, it has recently been intensively studied in a wide range of fields, including industry, medicine and security. Three-dimensional image measurement technologies can be broadly classified into passive techniques, such as stereovision and active techniques, such as patterned light projection. Among these, the method of projecting optimum intensity modulated light patterns for three-dimensional image measurement can obtain three-dimensional information on the measured object with a single projection, so it is expected to be highly applicable in practice. Measurement can be performed using a single observation image when the object to be measured has simple colouration or surface reflectivity, but for complex objects, eliminating the influence of colour and surface reflectivity requires a reference image to correct the intensity of the observed pattern. To address this, we propose an analysis method and image correction technology, using a novel colour system for realizing three-dimensional measurements using only one observation image.