Teaching Practice about Flipped Classroom on Circuit Course

In view of the problems in circuit course, flipped classroom is introduced and new teaching mode is explored. Teaching design, teaching reform suggestion, teaching effects and results are presented. It is verified that this kind of teaching mode can enhance the enthusiasm, initiative and participation of the students, teaching efficiency is also improved. It is also a good way for comprehensive practice

Influence of crosswind on heller natural draft dry cooling tower and improvement measures

With the risk of water resources increasingly heavier and the need of the inland development of the nuclear power, dry cooling tower in power plant with its excellent water conservation characteristics, gets more and more attentions from the countries all over the world, especially in coal-rich but water-short areas. There are mainly three dry cooling tower forms: the air-cooled condenser(ACC), the natural draft dry cooling tower with surface type condenser(Harman system) and the natural draft dry cooling tower with jet condenser(Heller system).The radiator of Heller dry cooling tower is fixed up vertically all around the tower. Its heat transfer performance is greatly affected by environmental conditions, especially the crosswinds. The study of the effects of the crosswinds to the flow and heat transfer performance is essential to the design and optimization of the air cooling tower. Hence, the effects of the crosswinds to the flow and heat transfer performance of the air cooling system are investigated by a hot state model experimental platform. A new method adding air leading plates all around the tower to eliminate or ease the adverse effect of the crosswinds is put forward. The results show that the cooling tower flow field and temperature field are in symmetry without crosswinds. The flow and heat transfer performance of Heller air cooling system in different locations will encounter varying degrees of influence under crosswinds. The total air flow rate and the total heat transfer rate are also influenced. Under high crosswinds, airflow from windward side will oppress that from tower side and leeside. Flow a round circular cylinder is also formed. At this time, radial wind speed and effective into tower wind speed are small in tower side and leeside, heat transfer effect is poorer. The worst parts of flow and heat are mainly in the tower side. The influence mechanisms of environmental crosswinds and the certainty of heat transfer deterioration parts point out the direction for the further precautions. Adding air leading plates all around the tower is a very effective windproof measure which can improve the operating conditions greatly, change negative effect to positive effect.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

Dual-Decoder Consistency via Pseudo-Labels Guided Data Augmentation for Semi-Supervised Medical Image Segmentation

Medical image segmentation methods often rely on fully supervised approaches to achieve excellent performance, which is contingent upon having an extensive set of labeled images for training. However, annotating medical images is both expensive and time-consuming. Semi-supervised learning offers a solution by leveraging numerous unlabeled images alongside a limited set of annotated ones. In this paper, we introduce a semi-supervised medical image segmentation method based on the mean-teacher model, referred to as Dual-Decoder Consistency via Pseudo-Labels Guided Data Augmentation (DCPA). This method combines consistency regularization, pseudo-labels, and data augmentation to enhance the efficacy of semi-supervised segmentation. Firstly, the proposed model comprises both student and teacher models with a shared encoder and two distinct decoders employing different up-sampling strategies. Minimizing the output discrepancy between decoders enforces the generation of consistent representations, serving as regularization during student model training. Secondly, we introduce mixup operations to blend unlabeled data with labeled data, creating mixed data and thereby achieving data augmentation. Lastly, pseudo-labels are generated by the teacher model and utilized as labels for mixed data to compute unsupervised loss. We compare the segmentation results of the DCPA model with six state-of-the-art semi-supervised methods on three publicly available medical datasets. Beyond classical 10\% and 20\% semi-supervised settings, we investigate performance with less supervision (5\% labeled data). Experimental outcomes demonstrate that our approach consistently outperforms existing semi-supervised medical image segmentation methods across the three semi-supervised settings

Application of brazing process design in optimization structure design of scraper

To effectively enhance the service life, the research of milling machine scraper structure design and welding process are optimized. Through the structural optimization analysis, the improved structure is obtained, and the working resistance force is reduced. The full factor test is used to optimize the brazing process, and the best parameters are obtained, which improves the shear strength. The accuracy of the model is verified by experiments. The results show that compared with the working resistance force, the improved scraper tends to be slow and the peak value is smaller. The cutting rake and relief angle of the scraper are optimized. When the cutting rake angle is 6° and the cutting relief angle is 9°, both working resistance force and impact force are minimum. It proves the accuracy of the simulation results. Using CT861 solder, brazing temperature is 75°C, and the brazing time is 10s. While the cooling method uses furnace cold, the minimum value of shear strength is 200MPa. The average working life of the scraper is raised from 800 hours to 1600 hours after the optimization design. Research results have guiding significance for the structure design and the welding process optimization of the scraper

Application of brazing process design in optimization structure design of scraper

To effectively enhance the service life, the research of milling machine scraper structure design and welding process are optimized. Through the structural optimization analysis, the improved structure is obtained, and the working resistance force is reduced. The full factor test is used to optimize the brazing process, and the best parameters are obtained, which improves the shear strength. The accuracy of the model is verified by experiments. The results show that compared with the working resistance force, the improved scraper tends to be slow and the peak value is smaller. The cutting rake and relief angle of the scraper are optimized. When the cutting rake angle is 6° and the cutting relief angle is 9°, both working resistance force and impact force are minimum. It proves the accuracy of the simulation results. Using CT861 solder, brazing temperature is 75°C, and the brazing time is 10s. While the cooling method uses furnace cold, the minimum value of shear strength is 200MPa. The average working life of the scraper is raised from 800 hours to 1600 hours after the optimization design. Research results have guiding significance for the structure design and the welding process optimization of the scraper

Local Memory Search Bat Algorithm for Grey Economic Dynamic System

Control system is a pattern for describing microeconomic performance, so it can provide theory basis for policy-making to make economic performance well and continuously by analyzing and solving the model of economic control system. After analyzing the characteristics of Bat Algorithm (BA), the method to adjust each step of BA is proposed. In the method, each bat took advantage of the optimal location that it had found to guide the direction of search. The result of the case study showed that the proposed algorithm was efficient, then the proposed algorithm was used to solve the grey economic dynamic system, and the results further showed that the method was valid for solving economic control problems. DOI: http://dx.doi.org/10.11591/telkomnika.v11i9.314

Detection of groundwater storage variability based on GRACE and CABLE model in the Murray-Darling Basin

Monitoring groundwater storage is in great importance for economic and social development. In this paper, the monthly GRACE data from 2003 to 2015 is combined with the Community Atmosphere Biosphere Land Exchange (CABLE) model to estimate the variations of groundwater storage (GWS) in the Murray-Darling Basin (MDB). The results show that (1) the simulations of TWS from CABLE are more accurate than GLDAS over the MDB, and there is a higher correlation coefficient of 0.94 and a lower RMSE of 15.74 between CABLE and GRACE. (3) The spatial pattern of GWS trends shows decline trends in the southwest, east and south, and increasing trends in the north and south central (3) For the whole MDB, the average GWS has strong seasonality and shows an increasing trend with a rate of 1.19 0.41 mmyyear between 2003 and 2015

Nausea and Desire in Sartre's La Nausée

Expression profile of superoxide dismutase (SOD) gene at different developmental stages of S. japonicum. Real-time PCR was performed to detect the transcripts of SOD at life stages of cercaria, young worm (Young), adult worm (Adult) and egg. Data were analyzed according to 2 − Ct method using GAPDH as the internal control for each sample. The-fold changes of gene transcriptional level in young worm, adult worm and egg were calculated as compared with cercaria. (PDF 73 kb