Tracking the information about your manuscript
Communicate with the editorial office
Query manuscript payment status Editor LoginCollecting, editing, reviewing and other affairs offices
Managing manuscripts
Managing author information and external review Expert Information Reviewer LoginOnline Review
Online Communication with the Editorial Department
WeChat Official Account
Page Views
High-performance research facilities empower engineering resilience enhancement: The construction, development, and innovative practice of multi-functional shaking tables
CAO Shuang;LI Ying;ZHANG Guowei;JIAO Chiyu;LI Aiqun;[Significance] Engineering resilience relates to the ability of urban buildings, underground spaces, transportation infrastructure, historical buildings, and other engineering structures to withstand severe disasters, maintain their functions to the greatest extent during their entire service life, and recover quickly after a disaster. China experiences frequent earthquakes, and determining the seismic performance of engineering structures is crucial for improving seismic safety and serves as a fundamental basis for protecting human life, ensuring social and economic stability, and promoting sustainable development. [Progress] Shaking tables are one of the important experimental facilities used in seismic research. After more than half a century of development, China has made leapfrog progress in both the quantity and performance parameters of these systems. However, with the accelerated urbanization process and the increasing demand for a better life, complex and large-scale structures such as high-rise buildings, subway stations, urban diverging bridges, utility tunnels, large-span spatial structures, long-span bridges, nuclear power plants, and water conservancy projects continue to be constructed, posing greater challenges to engineering seismic research. As the political and cultural center of China, Beijing is located in a high-intensity seismic zone and is a key focus area for seismic monitoring and defense. The seismic safety of its infrastructure is particularly significant. However, existing large-scale structural dynamic laboratories around Beijing are mostly equipped with single shaking tables, and owing to limitations in table size and load capacity, they are unable to meet the experimental research requirements for large-scale, long-span, or other complex structures and infrastructures. Therefore, in active response to the strategic deployment of disaster prevention and mitigation by the CPC Central Committee, Beijing University of Civil Engineering and Architecture has completed the construction of a multi-functional shaking table system. This system aims to significantly elevate the modernization level of China's seismic research facilities, providing powerful technical support for the seismic design and operational management of major national projects. It simultaneously enhances the capabilities of fundamental research while achieving major technological breakthroughs in engineering resilience. The system comprises four triaxial, six-degrees-of-freedom, multi-functional, shaking tables, each measuring 5 m × 5 m. These tables can be moved to any position on the rails and can be operated independently or in combination as a multi-table array system(in pairs, triplets, or all four). The system is capable of conducting single-table or multi-table vibration tests and can accommodate large-scale model tests with a maximum combined table size of 19 m × 30 m. [Conclusions and Prospects] This system features the largest total payload capacity and able area among all existing four-table array systems worldwide, with technical parameters that reflect the latest advancements in the field. To simultaneously enhance the management level and operational skills of laboratory technicians and expand the scope and depth of shaking tables and how they assist society, the Multi-functional Shaking Tables Laboratory of Beijing University of Civil Engineering and Architecture actively promotes inter-departmental collaboration and information sharing. The laboratory also focuses on optimizing management mechanisms and gradually establishes a full life-cycle open-sharing management system. To date, these high-performance multi-functional shaking tables have successfully completed approximately 20 seismic performance tests and shaking table model experiments.
Experimental calibration-based comparison of the seismic performances of curved bridges with variable pier heights
JIAO Chiyu;ZHOU Jiaxin;LI Yangjie;HE Peijian;Beijing Urban Transportation Infrastructure Construction Engineering Technology Research Center;[Objective] Curved girder bridges with variable pier heights and small curvature radii are widely adopted in modern transportation infrastructure due to their adaptability to complex terrain and urban landscapes. However, this irregular spatial configuration significantly increases their mechanical complexity under seismic loading. Post-earthquake investigations, such as those following the devastating earthquakes in regions like Japan and California, have demonstrated that these geometric characteristics substantially elevate structural vulnerability. The curvature-induced centrifugal forces, combined with the differential displacements caused by varying pier heights, often lead to concentrated damage at critical components, including pier bases and bearings. As such, the optimization of bearing configurations emerges as a crucial strategy for mitigating seismic responses in these geometrically complex bridges, aiming to enhance structural integrity and safety during seismic events. [Methods] This investigation centers on a prototype 4×20 m concrete curved bridge with a 50 m radius. To accurately assess its seismic performance, the bridge was scaled down to 1/20 through meticulous dimensional analysis for shaking-table testing. The scaled model was subjected to a series of dynamic loading scenarios, simulating real-world seismic conditions. Concurrently, a refined finite element model was developed using advanced engineering software. This model was rigorously validated against the experimental results, ensuring its reliability for further analysis. This validation process allowed for a comprehensive comparative analysis of seismic performance across different pier-girder connection systems. Three distinct intermediate pier configurations were then systematically examined through nonlinear time-history analysis under bidirectional seismic excitation, enabling a detailed exploration of their dynamic responses and failure mechanisms. [Results] For four-span curved bridges with height-varying piers, the intermediate pier bearing configuration exerts a pivotal influence on global seismic performance, especially when transition piers utilize unidirectional sliding bearings. Numerical simulations, supported by detailed data analysis, reveal that the proposed hybrid system, which combines sliding bearings at tall/medium piers with fixed bearings at short piers, demonstrates superior mechanical behavior compared to conventional fully-fixed configurations. Specifically, the hybrid system reduces pier-bottom moment peaks by up to 35% and shear force peaks by 30% through optimized force redistribution. Despite these significant reductions in internal forces, it maintains comparable displacement control capacity. Notably, the hybrid configuration effectively mitigates moment concentration at critical pier bases and constrains structural displacements within operational thresholds, significantly enhancing the bridge's capability to prevent girder unseating during extreme seismic events. [Conclusions] Mechanistic analysis reveals that the hybrid system fundamentally alters internal force distribution patterns, concentrating moments at strategically reinforced short piers while redistributing seismic energy through controlled sliding. Compared to fully-fixed systems, the hybrid configuration achieves a 30%～35% reduction of internal force concentration at critical pier locations while maintaining effective displacement control. This study establishes that the rational allocation of fixed bearings to shorter piers combined with sliding mechanisms at taller piers creates an optimal stiffness distribution for seismic energy dissipation. The validated numerical framework and proposed design methodology provide both theoretical foundations and practical guidelines for performance-based seismic design of spatially complex bridge systems. These findings offer essential insights for enhancing structural safety and reliability in earthquake-prone regions, potentially leading to the development of more resilient bridge designs in the future.
Modal parameter identification in shaking table tests using stochastic subspace method: Taking the scale model of a super high-rise building as an example
ZHANG Guowei;LI Jianying;ZHANG Hong;QIN Chang'an;YANG Xinyu;[Objective] Owing to their extreme height, extended fundamental frequencies, and complex mode shapes, supertall buildings have consistently posed challenges in seismic performance assessments, especially in regions experiencing high seismicity. As a widely adopted experimental approach, shaking table tests provide critical insights into the dynamic response and failure mechanisms of such structures under earthquake loading. A key step in such tests involves the identification of structural modal parameters, which traditionally relies on white noise excitation due to its broadband, uniformly distributed frequency content, and technical maturity. However, for the scaled models of supertall structures, which are typically characterized by reduced stiffness and low natural frequencies, long-duration white noise excitation can induce cumulative microdamage. Such subtle yet potentially irreversible changes, such as local cracking or stiffness degradation, may adversely influence the structural response under subsequent seismic excitations, thereby compromising the accuracy of performance evaluation. [Methods] This study investigates the feasibility of using a stochastic subspace identification(SSI-Dat) method for extracting the modal parameters of a scaled supertall building model directly from seismic response data, thereby avoiding potential model degradation associated with traditional white noise excitation. A series of shaking table tests are conducted under three levels of the seismic input(e.g., minor, moderate, and major earthquakes), corresponding to a seismic fortification intensity of 7. The method utilizes measured acceleration time histories to construct a system observation matrix from which natural frequencies, damping ratios, and dominant mode shapes are extracted via subspace decomposition. To evaluate the reliability and accuracy of the SSI-Dat method, the identified modal parameters are compared with those obtained from white noise excitation using the frequency response function(FRF) method under identical test conditions. [Results] To validate the accuracy and reliability of the SSI-Dat method, the identified modal parameters are compared with those obtained through conventional white noise excitation using the FRF method after each seismic event. Results show that, under minor seismic excitation, the SSI-Dat method yields modal parameters that noticeably deviate from those derived via the white noise approach, likely due to insufficient energy input and limited excitation in high modes. Meanwhile, under moderate and major earthquake inputs, the identified modal parameters, especially fundamental frequencies and dominant mode shapes, exhibit good agreement with the white-noise-based results. This indicates that, as input energy increases, the dynamic response of the structure becomes richer in the modal content, thereby enhancing the effectiveness of subspace-based identification techniques. Throughout the tests, the structure mainly exhibits horizontal motion with minimal torsion. Post-test modal shifts indicate damage accumulation, especially under strong quakes. Despite local stiffness degradation and cracking, the model remains globally intact, retaining load-bearing capacity. This reflects the realistic seismic performance of the supertall building and validates the scaled model's structural fidelity. [Conclusions] This study demonstrates the feasibility and reliability of using the SSI-Dat method to identify the modal parameters of scaled supertall building models under seismic excitation. Compared to the conventional white-noise-based approach, this method avoids risks associated with prolonged artificial excitation and offers a more realistic representation of the structural dynamic characteristics. These findings provide a valuable methodological reference for future shaking table tests involving high-rise structures and contribute to the advancement of nonintrusive modal identification techniques in seismic tests.
Shaking table experimental study considering the coupling effect of large-scale building equipment and structures
QIN Chang'an;ZHANG Guowei;SONG Jincheng;WANG Chen;ZHOU Zhou;XIONG Ziyan;[Objective] This study investigates the interaction between equipment and building structures, with a focus on how equipment mass and stiffness influence the dynamic response of these structures. To achieve this, large-scale shaking table tests were conducted using a scaled model of a benchmark steel frame of the equipment. [Methods] The equipment model was based on a water-cooling machine, a crucial component of large-scale equipment used in industries relating to the medical, chemical, and high-tech sectors. The selection of the model considers the overall weight, vibration characteristics, and other features of this type of equipment. The decoupling reconstruction method was used to decompose the equipment system into mass and stiffness characteristic components. The scaled model of the main structure used a benchmark steel frame, which is a standard model for structural analysis and validation research. The El Centro seismic wave was applied as an input to the shaking table at a maximum peak acceleration of 0.4 g, complemented by a white noise input of 0.05 g before and after each test. For the coupled system, connectors with varying stiffness were sequentially swapped under each counterweight level, resulting in five tests and 25 working conditions. Through these large-scale shaking table tests, the frequencies of the equipment at different masses and stiffnesses were analyzed, along with the effects of equipment frequencies on the vibration modes and dynamic responses of the coupled system. The acceleration time-history curves were directly recorded using acceleration sensors, while displacement time-history curves were derived through integration methods. [Results] As the frequency of the equipment decreased, the first mode shape of the main structure transitioned from translational motion to stationary, while the third mode shape shifted from torsional to translational. The first and second mode shapes of the equipment evolved from relatively stationary to translational. High-frequency equipment can be regarded as an additional mass for the seismic performance analysis of coupled systems. The coupling effect sharpened the acceleration time-history curve of the main structure, increasing the peak during intense vibration periods and decreasing the peak during mild vibration periods, while the acceleration time-history curve of the equipment exhibited an opposite evolutionary pattern. As the frequency of the equipment decreased, the maximum acceleration peak of the structure first decreased and then increased, whereas the equipment displayed a trend of first increasing and then decreasing. The equipment tended to suppress the acceleration response of the structure. The coupling effect also sharpened the displacement time-history curve of the main structure, resulting in a reduction in the displacement amplitude, while the displacement amplitude of the equipment demonstrated similar characteristics. As the frequency of the equipment decreased, the maximum peak displacement of the structure first decreased and then increased, while the equipment showed a trend of first increasing and then decreasing, indicating that the equipment can suppress the displacement response of the structure. [Conclusions] In seismic design, it is essential to analyze equipment and structure as integrated systems to accurately assess their actual responses under seismic action, thereby avoiding unnecessary increases in cost due to overestimating seismic demand. Additionally, placing equipment sensitive to acceleration responses, which may induce adverse resonance, should be avoided in areas identified as seismically weak. This research provides theoretical support for the seismic design of coupled equipment-structure systems.
Experimental design for single-phase grounding fault section selection in distribution networks based on transient zero-sequence power characteristics
GAO Wei;ZHENG Zijie;LI Yufeng;LIN Jianxin;GUO Moufa;[Objective] A single-phase grounding fault is the most frequent type of fault in distribution networks, and identifying the fault accurately and locating the fault section for the safe operation of power networks is crucial. However, because of small fault current, weak fault characteristics, and poor dispersion, the accuracy of fault location in engineering practice is low. In order to enhance the quality of experimental teaching, students' cognition of single-phase grounding fault in distribution networks, and their practical analytical skills, this paper presents an experimental design scheme for the resonant grounding fault segment in distribution networks. [Methods] First, the design method of the single-phase grounding fault experiment platform is described, including the components of the 10 kV true type experiment system and the hardware and software designs of the single-phase fault grounding current identification terminal to build a real experimental environment for the research. Second, the design scheme of the distribution network grounding fault section is proposed. After an in-depth analysis of the polarity differences between the transient zero-sequence signals in the healthy section and the faulty section, it is found that when transient zero-sequence power is directly calculated, misjudgment will occur because of the influence of arc suppression coil compensation and noise interference. However, some frequency band information of the zero-sequence power contains characteristic information that can effectively suppress the interference. Based on this, the transient zero-sequence power is decomposed by a wavelet packet algorithm, in which the frequency band with strong energy entropy can stably reflect the state characteristics of the line. Considering the randomness and uncertainty of the fault arc and the presence of field noise, the high-entropy characteristic frequency bands of each fault sample are not the same, and the number of characteristic frequency bands available for selection is large. Therefore, this paper further proposes a feature frequency band optimization method based on a genetic algorithm and wavelet packet energy entropy. In the offline stage, the genetic algorithm is used to screen the massive historical data and optimize the selection of feature frequency bands to improve the identification accuracy of the fault section. In the single calculation stage, the five frequency bands with the highest wavelet packet energy entropy are selected as the characteristic frequency bands, and then, the fault characteristic frequency bands with strong characterization ability are determined by intersection operation. This method can effectively suppress the noise interference and enhance the identification performance of the fault section. [Results] Experimental results show that the proposed method is highly adaptive, requires no threshold in ground fault current identification, and achieves an accuracy of 95.24%. Compared with other methods in the literature, the proposed method can maintain higher recognition performance under various working conditions. Finally, hierarchical experiment schemes are designed according to different curriculum requirements for students to gradually master the whole process from fault mechanism analysis to advanced intelligent identification methods. [Conclusions] The experimental platform and single-phase grounding fault identification method not only improve the students' hands-on and engineering application capabilities but also lay the foundation for further research and application of single-phase grounding fault detection technology in distribution networks and provide an innovative practical teaching model for the cultivation of talent in the field of power engineering.
Novel capacitance detection analog interface asic based on time-multiplexed fully differential technology
FANG Shuo;HOU Changbo;WANG Lijing;LIU Yuntao;SHAO Lei;[Objective] Capacitance detection has emerged as a highly accurate technique for micro-electromechanical system(MEMS)sensors, owing to its compatibility with integrated circuits(ICs), low drift current, minimal temperature dependence, and low power consumption. The resolution of capacitance detection interface ICs based on the CMOS process is mainly limited by the DC offset and 1/f noise of the charge amplifier. Although the fully differential structure of the switched capacitor auto-zeroing and correlated double sampling(CDS) improve the resolution, the capacitance detection interface ICs still suffer from nonlinear problems caused by common mode errors, mismatches, and complex operations. The nonlinear problems hinder further improvement of the capacitance detection resolution. This paper presents a novel time-multiplexed fully differential(TMFD) capacitance detection interface application-specific integrated circuit(ASIC) with high linearity developed to improve the resolution, sensitivity, and dynamic range of MEMS sensors.[Methods] The proposed ASIC adopted a CDS architecture to enhance the CMRR. Key components included a C-V converter,programmable gain amplifier(PGA), low-pass filter, clock generator, reference voltage circuit, temperature sensor, and one-time programmable memory. Unlike conventional full-bridge sensing structures, the interface employed a novel TMFD C-V converter based on a half-bridge measurement configuration and two single-ended charge amplifiers, enabling TMFD detection. To address nonlinearity from unbalanced parasitic capacitance, the converter performed precise capacitance compensation in each clock cycle. In addition, it reduced the gain at the virtual ground node, thereby suppressing common-mode voltage effects during charge transfer. The PGA used a fully differential switched capacitor design to suppress nonlinear fluctuations and enhance stability. A multiple feedback low-pass filter was applied to eliminate high-frequency noise and reduce residual nonlinear distortion. A temperature sensor enabled temperature calibration,mitigating nonlinearity induced by temperature fluctuations. [Results] The novel capacitance detection analog interface ASIC designed has a strong nonlinear suppression ability and significantly improves the detection range and accuracy of MEMS sensors. While connected to the MEMS accelerometer, the experimental results of the novel TMFD capacitance detection interface ASIC showed the following merits:1) The detection sensitivity of the interface ASIC reached 1.342 V/g, and the detection range achieved ±3 g. 2) The noise performance and bias stability significantly improved, and the noise floor decreased to 10.5 μg/Hz1/2. 3) The range of the maximal output variation within 4 h was only 0.3 mV. 4) The temperature sensitivity ratio was reduced to 0.007‰/°C. 5) The readout ASIC also operated at a low drive voltage(5 V), consumed low power(7.5 mW), and enlarged the bandwidth(1.5 kHz). The interface ASIC structure presented here is significantly superior to others that have been developed. [Conclusions] By integrating specific half-bridge TMFD detections and precise capacitance compensation, the novel capacitance detection analog interface ASIC has a strong nonlinear suppression ability, and the detection range and accuracy of MEMS sensors are significantly improved. The TMFD capacitance detection technology proposed in this paper further improves the accuracy of capacitance detection and significantly promotes the development and application of high-precision MEMS sensor systems.
An experiment on EEG emotion recognition based on SGC-Transformer network
SHI Kaibo;YANG Yong;TANG Lin;[Objective] Electroencephalography(EEG) emotion recognition holds wide application potential in mental health diagnosis,human-computer interaction, brain-computer interfaces, and personalized user experiences. However, the nonlinear characteristics, low signal-to-noise ratio, and non-stationarity of EEG signals challenge traditional methods in extracting stable emotional features. To advance science-education integration, we designed an innovative teaching experiment centered on EEG emotion recognition using an SGCTransformer network(SGCTNet). This architecture integrates graph neural networks and Transformers, leveraging graph convolutional networks'(GCN) strength in processing non-Euclidean spatial data and Transformers' capacity for capturing global dependencies.Additionally, to mitigate deep learning's reliance on large-scale datasets, we propose a data integration strategy enhancing inter-channel relationship modeling and generalization capability. [Methods] The proposed SGCTNet is a hybrid deep learning architecture fusing Simplified Graph Convolution(SGC) and Transformer modules for efficient EEG emotion recognition. First, the SGC module extracts topological spatial features between EEG channels by simplifying the GCN structure: removing intermediate nonlinear activation layers reduces model complexity while preserving rich spatial information. Second, the Transformer module employs a self-attention mechanism to comprehensively capture global long-range dependencies among channel nodes based on these topological features, strengthening channel information utilization efficiency. Furthermore, a data integration strategy improves generalization by incorporating EEG data from multiple historical experimental sessions into current training, maximizing existing data utility. Experiments utilized public datasets SEED and SEED-Ⅳ, employing control groups to systematically evaluate SGCTNet's performance across scenarios, validating model effectiveness and data strategy generalizability. [Results] Experimental results demonstrate significant performance improvements with SGCTNet. On SEED-Ⅳ, the model achieved accuracies of 82.45%, 85.23%, and 87.62% across three sessions. On SEED, it attained 94.94%, 94.21%, and 96.87% accuracy, outperforming traditional CNNs, SVMs, Random Forests, and other deep learning models. Further analysis confirmed the data integration strategy substantially enhanced generalization: accuracy increased by 5.22%(Session 2) and 7.83%(Session 3) on SEEDⅣ, and by 3.58%(Session 2) and 3.72%(Session 3) on SEED. [Conclusions] SGCTNet integrates graph structure modeling and self-attention mechanisms, demonstrating strong modeling capability and excellent generalization in EEG emotion recognition. The developed experimental system possesses significant pedagogical value, facilitating the practical application of deep learning in EEG signal processing and supporting talent cultivation in this field.
Comprehensive experimental design of solid-state fermentation on Pu-erh primary tea by Eurotium cristatum
SHAO Jufang;LENG Yunwei;PENG Yaoli;ZHU Hongwei;[Objective] An undergraduate teaching experimental project was designed based on an undergraduate innovation training program. The project aims to further improve the teaching system, enrich teaching content, develop students' independent thinking and problem-solving abilities, and cultivate high-quality top-notch talents. [Methods] Raw Pu-erh tea(Ligustrum robustum) was fermented via solid-state fermentation using Eurotium cristatum. The growth of Eurotium cristatum during fermentation was observed and examined microscopically using an optical microscope. Seven physicochemical indicators—water extract, caffeine, tea polyphenols, amino acids,total sugar, tea pigments(theaflavins, thearubigins, theabrownins), and hydrated pectin—were compared between raw and fermented Pu-erh tea. Volatile aromatic compounds in both tea samples were identified using gas chromatography-mass spectrometry(GC-MS), and their sensory quality was evaluated. [Results] Significant changes occurred in the seven physicochemical indicators after fermentation. Tea polyphenol and thearubigin content significantly decreased, while water extract, caffeine, amino acids, total sugar, hydrated pectin,theaflavin, and theabrownin content increased. Differences in the types and quantities of aromatic substances were observed: 34compounds were identified in raw tea versus 44 in fermented tea, primarily alcohols, ketones, esters, and aldehydes. The fermented tea exhibited superior sensory quality. Key improvements included an oily appearance with visible golden particles(enhanced ornamental value), a deeper yellowish-brown liquor, and a complex aroma featuring mushroom and fermented-aged notes. The taste was smooth,mellow, significantly less astringent, and had a long aftertaste. The fermented tea leaves were darker(yellowish-brown), smoother, and more elastic. Its sensory evaluation score was higher than that of raw tea. [Conclusions] Fermentation with Eurotium cristatum significantly improved the quality of raw Pu-erh tea. This project effectively addressed challenges such as students' limited experimental skills and access to advanced instrumentation by integrating multidisciplinary techniques with valuable equipment. Students mastered fundamental skills—microbial cultivation/observation, tea fermentation, physicochemical analysis, and GC-MS detection—while deepening their understanding of the relationship between physicochemical changes during fermentation and sensory quality. Their research literacy and innovation capabilities were effectively cultivated. With its interdisciplinary nature and ease of implementation, this project is an ideal comprehensive undergraduate experiment for biology, food science, and tea science programs, meeting the demands for innovative talent cultivation in the modern biology industry.
Mobile empowerment micro-experiment:Technical characteristics,mapping mechanism,teaching mode,and application practice
GUO Feng;FU Song;HE Jun;GAI Longtao;CHEN Peisheng;[Objective] Educational digitalization is a significant national strategy, and developing novel digital applications to empower teaching represents a crucial pathway for higher education reform. As experimental teaching constitutes a vital component of higher education, empowering it through digital technology is a key reform direction. To broaden the scope of digital empowerment and reduce end-user teaching costs, mobile micro-experiments have emerged as an important carrier for digitally empowered experimental teaching.However, research on the technical characteristics, mapping mechanisms, teaching models, and practical applications of mobile-empowered micro-experiments remains insufficient. To address this gap, the research team defined and investigated mobile micro-experiments. [Methods] Through literature review and technical capability analysis, the technical characteristics of mobile micro-experiments were examined. By comparative analysis with physical experiments, their mapping mechanisms were explored.Theoretical analysis was employed to study their teaching models, while empirical analysis evaluated their practical application. [Results]Technical Characteristics: Micro-intelligence(edge/cloud intelligence) supports teacher-guided experimental decisions; Micro-push uses a lightweight engine for personalized knowledge/operation delivery; Micro-operation leverages feasible space, reasonable boundaries, and efficient interaction to trigger consistent learning experiences; Micro-feedback offers targeted, detail-oriented feedback(individual unconscious/collective conscious); Micro-service enables modular content design, supporting adaptable learning paths. Mapping Mechanism(Digitization-Reality Dual Drive): Device constraints establish finite space simulation mapping(virtual?physical), enhancing teaching ubiquity; Online-offline integration enables hybrid interactive collaborative mapping, boosting teaching efficiency;Randomness-determinacy integration creates composite value-added mapping(collaborative mobile?physical devices), increasing teaching value. Teaching Mode: Perception teaching focuses on data analysis(teacher conscious active/student unconscious passive); Agile teaching emphasizes student response, encouraging unconventional thinking; Feedback teaching stresses case analysis and outcome evaluation via models; Extended teaching promotes practice expansion across time, space, and content. Application Practice:Design standards cover principle authenticity, volume adaptability, content clues, experience consistency, interactive usability, and process gameplay. Evaluation encompasses 36 indicators across experimental design, process, and results. [Conclusions] Mobile micro-experiments utilize mobile terminals as tools, mobile applications as carriers, and visual/interactive elements as objects. This approach demonstrably enhances students' practical and innovative abilities. Implementation analysis involving 72 junior undergraduates at H School confirmed that mobile micro-experiments significantly improve experimental efficiency and teaching quality. Students universally express high expectations for mobile-empowered micro-experiments.
Design of coal floatability evaluation experiment based on mathematical statistics
SUN Meijie;ZHONG Jiali;LI Jiangcheng;LYU Ziqi;TU Yanan;ZHOU Lingmei;XIE Weiwei;[Objective] The integration of theoretical knowledge and practical skills in mineral processing engineering education is crucial for cultivating students' scientific research capabilities and innovative thinking. It is necessary to optimize slime flotation conditions to improve coal recovery rates and reduce resource waste in mineral processing industries. To investigate the optimization of slime flotation through systematic experimental design and data analysis, this study focuses on the practical teaching modules of Design and Research Methods for Mineral Processing Experiments and Mineral Processing(2): Interface Sorting Technology. The key problem in selecting flotation process conditions under the influence of complex factors is addressed, as this directly affects the efficiency and quality of the flotation experiment exploration process. By incorporating orthogonal experimental design and statistical analysis into the curriculum, this research not only enhances students' hands-on skills but also bridges the gap between theoretical concepts and real-world applications.[Methods] A four-factor, three-level orthogonal experimental design was employed to evaluate the effects of collector dosage(Factor A),frother dosage(Factor B), pulp concentration(Factor C), and aeration rate(Factor D) on the coal slime flotation performance. The experiment was conducted using a single flotation cell, using coal samples from the Outer Mongolia Data Mine. Key performance indicators, including clean coal yield, concentrate ash content, and the flotation efficiency index, were measured using standardized procedures. Data analysis involved intuitive analysis and variance analysis. The experimental protocol emphasized student engagement in all stages, including design, operation, and analysis, to foster a comprehensive understanding of flotation dynamics and statistical methodologies. [Results] When employing intuitive analysis with the flotation efficiency index as the evaluation metric, the relative significance of individual factors was not considered. By comparing the k values(average flotation efficiency index of each factor level),the optimal levels for each factor were obtained: level 2 of Factor A, level 3 of Factor B, level 3 of Factor C, and level 1 of Factor D.Without considering significance, by comparing the range of k values(the difference between the maximum and minimum k values) and analyzing the primary and secondary effects of various factors, the frother dosage(Factor B) was found to have the most significant impact on the flotation perfection index among the four factors, followed by the aeration rate(Factor D). The pulp concentration(Factor C) had a more significant impact, and the collector dosage(Factor A) had the lowest impact. The optimal experimental plan was determined as B3D1C3A2. Subsequent variance analysis revealed that factors A, B, C, and D all exerted statistically significant effects on the flotation efficiency index with minimal experimental error. The relative influence of each factor on the flotation efficiency index was quantified by comparing their variance magnitudes: Factor B > Factor D > Factor C > Factor A, consistent with the trend identified through range analysis. This alignment between variance-based rankings and range analysis outcomes further validated the selection of B3D1C3A2 as the optimal condition combination. [Conclusions] This study successfully integrated orthogonal experimental design into mineral processing education, thereby achieving dual objectives: identifying optimal coal slime flotation parameters and cultivating students' scientific acumen. Orthogonal experimental design is a statistical methodology effectively applicable to flotation experiment design, and it leverages its inherent advantages of “balanced distribution” and “uniform comparability” to achieve the identification of optimal solutions while comprehensively assessing the relative significance and statistical impact of individual factors on experimental outcomes. This approach not only reduces the number of required trials and associated workloads, which can thereby shorten experimental timelines, but it also minimizes caused by random variations in conventional methods through the rigorous statistical analysis of holistic datasets. In course instruction and undergraduate innovation training programs, students should conduct extensive literature reviews and participate in regular group discussions to exchange ideas. This framework would cultivate multifaceted competencies, including literature retrieval abilities,self-directed learning, integration of theoretical knowledge with practical operations, and hands-on problem-solving. Furthermore, the application of statistical methods for processing and interpreting experimental results exemplifies the pedagogical benefits of interdisciplinary integration.
Study on the design and analysis methods of orthogonal experiment
Liu Ruijiang,Zhang Yewang,Wen Chongwei,Tang Jian(School of Pharmaceutics,Jiangsu University,Zhenjiang 212013,China)The importance of orthogonal experimental design and analysis is introduced briefly.The principle and characteristic are expounded.The design methods of orthogonal experiment and analysis methods of orthogonal experimental results are analyzed in detail,which afford fully systemic methods for orthogonal experimental design and analysis.Problems in orthogonal experimental design and analysis and development of software for orthogonal experimental design and analysis are also pointed out in the end.
[Downloads: 52,870 ] [Citations: 3,083 ] [Reads: 35 ] HTML PDF Cite this article
Research on statistical analyses and countermeasures of 100 laboratory accidents
Li Zhihong;Training Department,Kunming Fire Command School;This paper summarizes 100typical cases of laboratory accidents from 2001and analyzes the cases in fields of accident type,accident link,accident cause,dangerous substance category,etc.The result shows as follows:the fire disasters and explosive accidents are the main types of laboratory accidents;the dangerous chemicals,instruments and equipment,and pressure vessels are main dangerous substances;the instruments and equipment and reagent application processes are the main links of accidents;the violation of rules,improper operation,carelessness,wire short circuit and aging are the main reasons of accidents.It also puts forward the countermeasures and suggestions for the prevention and control of laboratory accidents in the following aspects:establishing complete safety management system,actively promoting standard construction of laboratory safety,strengthening laboratory safety education and training,and formulating and improving emergency plans for laboratory accidents.
[Downloads: 9,140 ] [Citations: 492 ] [Reads: 27 ] HTML PDF Cite this article
Constructing practice teaching system focusing on ability training
Zhang Zhongfu(Zengcheng College,South China Normal University,Guangzhou 511363,China)The economic and social development has given rise to an increasing demand for applied talents,and people have attached more and more importance to practice teaching.The practice teaching system should focus on ability training,build practice teaching system,adjust the practice teaching contents,reform practicing teaching pattern,coordinate practicing teaching administrating system,and constructing a scientific and reasonable quality ensuring system and a practicing teaching evaluation system.
[Downloads: 4,161 ] [Citations: 253 ] [Reads: 34 ] HTML PDF Cite this article
The application of studying fluorescence spectroscopy on protein
Yin Yanxia,Xiang Benqiong,Tong Li(College of Life Science,Beijing Normal University,Beijing 100875,China)Fluorescence spectroscopy is very important for studying protein structure and conformation changes.The concept and principle of fluorescence spectroscopy are introduced at first,then the application of studying fluorescence spectroscopy on protein is explained.
[Downloads: 5,113 ] [Citations: 252 ] [Reads: 28 ] HTML PDF Cite this article
The CNC machine tool with systematic work process and its application of teaching design
Li Yanxian(Department of Mechanical and Electronic Engineering,Nanjing Communications Institute of Technology,Nanjing 211188,China)According to professional training objectives and the main jobs of the structure of vocational skills and knowledge required to "CNC machine tools and spare parts" for the carrier,taking the CNC programming and operation of capacity-building as the center,this paper shows the design of the "knowledge of CNC machine tools,observation and analysis of CNC lathes,CNC milling machine to observe and analyze the processing center,programming and processing stepped shaft,threaded shaft of the programming and processing,hand wheel slot programming and processing,convex programming and processing of the template,the base of the programming and processing"of 9 items,25 learning environment,67 tasks,and one of the "convex template programming and processing" learning environment for the teaching unit design.
[Downloads: 382,855 ] [Citations: 6 ] [Reads: 28 ] HTML PDF Cite this article
Study on the design and analysis methods of orthogonal experiment
Liu Ruijiang,Zhang Yewang,Wen Chongwei,Tang Jian(School of Pharmaceutics,Jiangsu University,Zhenjiang 212013,China)The importance of orthogonal experimental design and analysis is introduced briefly.The principle and characteristic are expounded.The design methods of orthogonal experiment and analysis methods of orthogonal experimental results are analyzed in detail,which afford fully systemic methods for orthogonal experimental design and analysis.Problems in orthogonal experimental design and analysis and development of software for orthogonal experimental design and analysis are also pointed out in the end.
[Downloads: 52,870 ] [Citations: 3,083 ] [Reads: 35 ] HTML PDF Cite this article
Construction and actualization of new experimental teaching system for chemical specialty
YANG Jin-tian(Institute of Life Science,Huzhou Normal College,Huzhou 313000,China)The new system of chemical experiment teaching is constructed,and the comprehensive experiments,open experiments and research-oriented experiments are set up to improve the degree of source sharing,the efficiency of using equipment and the quality of experimental teaching,hence efficiently optimizing the practical abilities and fostering innovative spirit for the undergraduates are achieved.
[Downloads: 24,228 ] [Citations: 11 ] [Reads: 31 ] HTML PDF Cite this article
Practice and thinking of education of“College Students' Innovative and Entrepreneurial Training Program”based on tutor system
Qian Xiaoming;Rong Huawei;Qian Jingzhu;Office of Academic Affairs,Nanjing University of Technology;The innovation and entrepreneurship education has been included in the teaching and education program of college schools."College Students' Innovative and Entrepreneurship Training Program "has become an"Excellent Program"as one of the most important reform tasks in Ministry of Education.The tutor system is an effective way of innovative education and pilot training for both college schools and students.Students learn the method of innovation researches and technique of entrepreneurial process through the program.In the meanwhile,teachers in college schools find a new stage to improve their teaching ability.This article focuses on the project,practice and feasibility of the"College Students' Innovative and Entrepreneurial Training Program "under the tutor system.
[Downloads: 10,004 ] [Citations: 219 ] [Reads: 35 ] HTML PDF Cite this article
Experimental research on protein immunoblot assay
ZHANG Yan-wan,YE Jue,SHI Na,MENG Xian-min,WANG Lai-yuan(Central Laboratory,Fuwai Hospital for Cardiology,Chinese Academy of Medical Sciences,Beijing 100037,China)The paper discribes the important significance of protein immunoblot assay(Western blotting) in the research on protein,the experiment principle and the methods of protein immunoblot assay.A few main aspects of experiment technology methods are analyzed and discussed,and the research experience of protein immunoblot assay is also discribed.
[Downloads: 9,231 ] [Citations: 105 ] [Reads: 33 ] HTML PDF Cite this article