Tsinghua University Research Articles

Exploring the Nexus of Electric Vehicles, Environmental Health and Sustainability: A Comprehensive Bibliometric Review

This study analysed 636 papers from the Scopus database using bibliometric and graphical techniques to trace the evolving research on sustainability, environmental health (EH), and electric vehicles (EVs). Research patterns, notable authors, most contributing nations, associations, leading journals, and the most widely referenced publications were all noted. Although the top journals for EV policy research are Sustainability and Journal of Cleaner Production, Sovacool Bk is acknowledged as the most active contributor. The top two contributions are the USA and China, underscoring their vital roles in the creation of EVs and creative policies. The primary contributor to the field research is Tsinghua University. With the maximum citations, the study by Egbue (2012) in Energy Policy suggests a significant long-term influence. The study uses Bradford's Law to confirm that important research is concentrated in specific publications and Lotka's Law to analyse author productivity. The results indicate that certain authors are quite prolific, which are in line with Bradford's Law but not Lotka's Law. The seven thematic clusters that emerged were (a) "Sustainable transportation and policy," (b) "Sustainable mobility and energy," (c) "Environmental Impact and Circular Economy," (d) "Electric Vehicles Adoption and Climate Change," (e) "Battery and Lithium-Ion Technology," (f) "Shared and Connected Mobility," and (g) "Smart Grid and Vehicle-to-Grid Integration." Overall, the study highlights the importance of interdisciplinary EV research as well as the need for infrastructure, regulatory, and technology improvements to support sustainable EV adoption. By employing keyword co-occurrence analysis, the study offers academics and policymakers valuable information, establishing the framework for resolving problems and promoting innovation in the EV ecosystem.

Migration experience and risky financial assets investments of county households: evidence from China

Enhancing the support for inclusive finance in county economies is crucial in achieving the strategic goal of building financial power. Drawing upon the theoretical lens of county-level inclusive financial accessibility, this study examines the effect of the migration experience (ME) of county socialites on their risky financial assets investment (FAI) and the underlying mechanisms. We utilize data sourced from the County Consumption Survey, a nationwide effort by the Department of Sociology of Tsinghua University and the 58 Tongzhen Research Group. Our findings reveal that the ME of county socialites significantly boosts their likelihood of engaging in financial markets. Furthermore, housing inequality factors, such as housing property rights and housing loans, play a moderating role in the impact of individual ME on their FAI. Additionally, the financial concept has a masking effect rather than a mediating effect on the path of the ME affecting FAI. Notably, the promotion effect of ME displays heterogeneity. Specifically, ME has a stronger positive effect on FAI among college-educated groups, members of the Communist Party of China (CPC), and urban hukou residents than on those who have not completed college education, non-CPC members and rural hukou households. In light of these findings, we propose policy recommendations to optimize the distribution of financial services, adjust the housing equality policy, and enhance inclusive financial literacy.

Analysis of platelet transfusion efficacy during extracorporeal membrane oxygenation (ECMO) treatment in pediatric patients post-cardiac surgery-a retrospective cohort study.

Postoperative extracorporeal membrane oxygenation (ECMO) may be necessary for pediatric patients following cardiac surgery, with associated risks of thrombocytopenia and bleeding. Prophylactic platelet transfusions are utilized to mitigate these risks, but the effectiveness of platelet transfusion cannot be reliably predicted. The aim of this study was to investigate the effect of platelet transfusion during postoperative treatment with ECMO in children undergoing cardiac surgery and to explore the optimal transfusion thresholds to reduce the number of platelet transfusions in patients and reduce the risk of death. We included in our study patients from the Pediatric Cardiac Surgery Department at the First Affiliated Hospital of Tsinghua University who underwent cardiac surgery and received ECMO treatment from January 1, 2019, to December 31, 2023, and received platelets transfusion at least once during the ECMO therapy. The platelet counts were determined both before and 24 hours posttransfusion of the platelet product. The corrected count increment (CCI) was calculated for the effectiveness estimation of platelet transfusion. The research subjects were divided into 3 groups based on the platelet count before transfusion (pretransfusion platelet count ≤30×109/L was the low-threshold group, pretransfusion count 31-50×109/L was the medium-threshold group, and ≥51×109/L was the high-threshold group) and the effective rates of each group were calculated. A total of 11 patients received 47 platelet transfusions, an average of 4.27 ± 1.67 per patient. According to the 24-hour postinfusion platelet (Plt) corrected critical control increase index (24-hour CCI) ≥4500, the infusion was considered to be effective, and ineffective when the CCI was <4500. Out of these, 22 transfusions (46.8%) proved effective, whereas 25 (53.2%) were deemed ineffective. The effective transfusion rates across the 3 groups were 69.2%, 50%, and 27.7%, respectively. The efficacy of platelet transfusion may be higher if a low threshold of platelet transfusion is chosen during ECMO treatment, on the premise of ensuring life safety.

Preface

Summary of the 8th International Conference on Pumps and Fans 1. Background To further enhance domestic and international cooperation and exchange, better understand research hotspots, stimulate scientific research vitality, and build a high-level academic exchange platform, Yangzhou University and Tsinghua University jointly hosted the 8th International Conference on Pumps and Fans (ICPF) in Yangzhou, China, from 12th to 15th April 2024. This conference traces its origins to the first International Conference on Pumps and Fans held at Tsinghua University in 1992, with subsequent conferences held at Tsinghua University in 1995, 1998, and 2002; at Zhejiang University in 2010; at Tsinghua University again in 2013; and at Zhejiang University again in 2015. Participation is encouraged from individuals involved in all facets of fluid machinery. List of Purpose, Scope, Record, Acknowledgement, Appendix A: Committee, Scientific Committee are available in this Pdf.

Review of major scientific research achievements on the 40th Anniversary of the Re-establishment of Department of Biology at Tsinghua University

Review of major scientific research achievements on the 40th Anniversary of the Re-establishment of Department of Biology at Tsinghua University

The Path to Improvement of China's Professional Cultivation in the Perspective of Legal Clinics

Since its inception in the United States in the 1960s, the legal clinic has developed rapidly in the United Kingdom, Finland and other countries due to its characteristics of significantly improving students' practical ability. China has also joined this trend. Since 2000, seven universities, including Peking University and Tsinghua University, have taken the lead in introducing legal clinics, and other universities have followed suit. Although the application of legal clinic in major universities has been quite mature, its application has been limited to general undergraduate courses rather than vocational undergraduate courses. Therefore, the legal clinic has been in a blank state in vocational undergraduate courses which train practical talents. Based on the blank phenomenon of legal clinic in vocational undergraduate, this paper aims to explore the path of improvement of vocational training in the perspective of legal clinic. Through the research, it seeks to put forward practical suggestions to promote the effective use of legal clinic in vocational undergraduate, in order to better cultivate practical talents. The literature review method and comparative method are used to conduct an exhaustive research on the development history of legal clinics in the international arena and in China. By comparatively analysing the application of legal clinics in general and vocational undergraduate courses, the applicability and development path of legal clinics in vocational undergraduate courses are explored. The research found that although legal clinics have achieved remarkable results in general undergraduate courses, there is a gap in the field of vocational undergraduate courses. Through comparative analyses, a path for the improvement of the law clinic in vocational undergraduate is proposed, including suggestions for adaptive adjustment of the clinic model, broadening the field of cooperation, and strengthening cooperation with the industry. This research fills the research gap of legal clinics in the field of vocational undergraduate, and provides new perspectives and paths for colleges and universities in cultivating the practical ability of vocational undergraduate students. By promoting the application of legal clinic in vocational undergraduate, it can better meet the needs of the actual legal profession and provide substantial support for the cultivation of more comprehensive legal professionals.

Transitions in development - an interview with Fan Zhou.

Fan Zhou is a group leader at Tsinghua University, China, where he works on the molecular changes that underpin cell fate transitions during early embryogenesis. We met with Fan over Zoom to discuss his career path so far. He discussed how a chance foray into basic research following his undergraduate degree sparked a lifelong passion for developmental biology, and how his interest in technology development has fed into his independent research.

The Art of Sculpture in Public Space in China: The Wasteland Art Project

With the development of public art in China, artists have been experimenting with the artistic form and means of expression of public sculpture. Previously marginalised by public sculpture, wild non-urban areas have also begun to attract the attention of Chinese artists. The Wasteland art project, implemented in Guazhou, Gansu province, is very indicative in this regard. Sculptor Dong Shubin, a professor at Tsinghua University Academy of Fine Arts, is the initiator of this project and an experimental artist who aims to create a sustainable artistic community in the Gobi Desert in the northwest of the country. He believes that an artist should draw inspiration from a natural environment that is familiar to them, rather than simply imitate others or emphatically separate themselves from the general mass of people. After creating works such as Children of the Earth, Infinity, and Wind Talkers, Dong Shubin and his colleagues are gradually creating a Wasteland Art complex in the Gobi Desert.

Exploring the Intersection of Communication and Labor: A Dialogue with Dan Schiller

Abstract This paper came out of a research seminar at Tsinghua University. On November 16, 2023, Yuezhi Zhao, a communication scholar who studies the political economy of communication from a transcultural context, invited Dan Schiller, a critical political economy scholar and historian of information and communications to her doctoral course entitled A Global History of Journalism and Communication Theory at Tsinghua University, for an open dialogue. In this lively scholarly exchange, professors and student participants explored a wide range of issues at the nexus of communication, labor, and geopolitical dynamics from both historical and contemporary perspectives. In part 1 and 2, Yuezhi Zhao invited Dan Schiller to reflect on the intersections of communication and labor in the digital age; In Part 3, Dan Schiller responded to a list of questions submitted anonymously by the class ahead of time and identified by students on the spot.

Design and test of an X -band constant gradient structure

A light source project named very compact inverse Compton scattering gamma-ray source (VIGAS) is under development at Tsinghua University. VIGAS aims to generate monochromatic high-energy gamma rays by colliding 350-MeV electron beams with 400-nm laser photons within a 12-m beamline. To produce a high-energy electron beam in such a compact space, the system consists of an S-band high-brightness injector and six X-band high-gradient accelerating structures. The goal of the X-band structure is to operate at a high gradient of 80 MV/m. Therefore, we adopts the constant gradient traveling wave approach, where the iris from the first cell to the end cell is tapered. The structure has 72 cells, including 70 cells and 2 couplers, so we named it XT72. The frequency of XT72 is selected to 11.424 GHz, and the 2π/3 mode is adopted. In this paper, we present a comprehensive study covering the detailed design, fabrication, rf tuning, and high-power test results of the first XT72. Additionally, we compare the performance of this structure to that of the previous constant impedance structure. Our results demonstrate that the XT72 is capable of operating at an 80−MV/m gradient with a lower breakdown rate. This advancement paves the way for the development of VIGAS project and contributes to the wider application of X-band room-temperature high-gradient structures in compact accelerator facilities. Published by the American Physical Society 2024

Does Bank Monitoring Reduce Corporate Misreporting? Evidence from Foreign Bank Entry in China

We propose a model of bank monitoring and borrower financial misreporting. Using the staggered liberalization of the banking sector in China as a natural experiment, we find that, consistent with the model’s prediction, entry by more efficient foreign banks reduces corporate misreporting fraud. Fraud reduction is greatest among borrowers of foreign banks, but fraud also drops among borrowers of domestic banks, suggesting a spillover effect. As predicted by the model, fraud reduction is greatest for borrowers with higher levels of fixed assets or lower levels of current assets. Our evidence suggests that improved bank monitoring reduces financial misreporting. This paper was accepted by Tomasz Piskorski, finance. Funding: M. Li acknowledges support from the National Science Foundation of China [Project 71402078] and the Social Science Foundation of Tsinghua University [Project 2013WKZD004]. Supplemental Material: The online appendices and data files are available at https://doi.org/10.1287/mnsc.2022.02414 .

Preface

As an annual academic conference, ICPMS has been successfully held over the last 7 years in Shanghai, Hangzhou, Yichang and online platform, attracted delegates from more than 10 countries and regions including China, Thailand, Japan, the United States, South Korea. During May 23-25, 2024, the 7th International Conference on Physics, Mathematics and Statistics (ICPMS2024) was successfully held in Yichang, China and online platform! This conference included keynote speeches, invited speeches, oral and poster presentations, and featured multi-topic special sessions, including: Fusion and Plasma Physics, Gravitation and Cosmology, Non-localized quantum mechanics and quantum entanglement, Engineering Thermophysics, Electrical Materials and Applications. Prof. Lixing Zhou from Tsinghua University, Prof. Qiwei Zhan from Zhejiang University and Prof. Fang Wang from Beihang University attended the conference and delivered keynote speeches. In addition, experts and scholars from the University of Illinois Urbana Champaign, Surgut State University, Chinese Academy of Sciences, Huazhong University of Science and Technology, Harbin Institute of Technology, Northeastern University, and other universities and institutes shared more than 20 wonderful speeches. This conference proceedings included 22 accepted articles selected from 54 submissions, all the papers have been through rigorous review and process to meet the requirements of international publication standard. We would like to express our gratitude to the reviewers of these manuscripts, who provided constructive criticism and stimulated comments and suggestions to the authors. We are extremely grateful as organizers, technical program committee and editors and extend our most sincere thanks to all the authors for their excellent contribution and work. Our sincere gratitude also goes to the IOP Publishing editors and managers for their helpful cooperation during the preparation of the proceedings. On behalf of the Organizing Committee of ICPMS2024. List of Technical Program Committee is available in this Pdf.

A deep learning model for personalized intra-arterial therapy planning in unresectable hepatocellular carcinoma: a multicenter retrospective study

Unresectable Hepatocellular Carcinoma (uHCC) poses a substantial global health challenge, demanding innovative prognostic and therapeutic planning tools for improved patient management. The predominant treatment strategies include Transarterial chemoembolization (TACE) and hepatic arterial infusion chemotherapy (HAIC). Between January 2014 and November 2021, a total of 1725 uHCC patients [mean age, 52.8±11.5 years; 1529 males] received preoperative CECT scans and were eligible for TACE or HAIC. Patients were assigned to one of the four cohorts according to their treatment, four transformer models (SELECTION) were trained and validated on each cohort; AUC was used to determine the prognostic performance of the trained models. Patients were stratified into high and low-risk groups based on the survival scores computed by SELECTION. The proposed AI-based treatment decision model (ATOM) utilizes survival scores to further inform final therapeutic recommendation. In this study, the training and validation sets included 1448 patients, with an additional 277 patients allocated to the external validation sets. The SELECTION model outperformed both clinical models and the ResNet approach in terms of AUC. Specifically, SELECTION-TACE and SELECTION-HAIC achieved AUCs of 0.761 (95% CI, 0.693-0.820) and 0.805 (95% CI, 0.707-0.881) respectively, in predicting ORR in their external validation cohorts. In predicting OS, SELECTION-TC and SELECTION-HC demonstrated AUCs of 0.736 (95% CI, 0.608-0.841) and 0.748 (95% CI, 0.599-0.865) respectively, in their external validation sets. SELECTION-derived survival scores effectively stratified patients into high and low-risk groups, showing significant differences in survival probabilities (P<0.05 across all four cohorts). Additionally, the concordance between ATOM and clinician recommendations was associated with significantly higher response/survival rates in cases of agreement, particularly within the TACE, HAIC, and TC cohorts in the external validation sets (P<0.05). ATOM was proposed based on SELECTION-derived survival scores, emerges as a promising tool to inform the selection among different intra-arterial interventional therapy techniques. This study received funding from the Beijing Municipal Natural Science Foundation, China (Z190024); the Key Program of the National Natural Science Foundation of China, China (81930119); The Science and Technology Planning Program of Beijing Municipal Science & Technology Commission and Administrative Commission of Zhongguancun Science Park, China (Z231100004823012); Tsinghua University Initiative Scientific Research Program of Precision Medicine, China (10001020108); and Institute for Intelligent Healthcare, Tsinghua University, China (041531001).

Fabrication and high-power testing of an X-band high-power phase shifter for the very compact inverse Compton scattering gamma-ray source.

This paper proposed an X-band phase shifter for the very compact inverse Compton scattering gamma-ray source program at Tsinghua University and conducted its structure design, numerical simulation, fabrication, cold test, and high-power testing. This phase shifter is composed of a polarizer, circular waveguide, and a piston with a choke structure. The simulation results show that the reflection coefficient of the phase shifter is under -40 dB and the insertion coefficient exceeds -0.06 dB at the operating frequency of 11.424GHz. The phase variation is 20°/mm, and a linear phase change from 0° to 360° can be achieved with a piston displacement of 18mm. The manufactured phase shifter has exhibited good performance in the cold test by using the vector network analyzer. After 16h conditioning in the Tsinghua X-band high-power test stand, the phase shifter reached a peak power of 72MW at 230ns pulse width and a peak power of 82MW at 130ns pulse width. After processing signals from the high-speed oscilloscope, it was found that the transmission phase variations were in good agreement with the simulation results.

Association between the perceived built environment and health behaviors in older adults: a cross-sectional study from Beijing, China

BackgroundUnder the background of the increasing trend of population aging, the health and quality of life of older adults have become the focus of social concern. As an important part of older adults’ daily life, the design and configuration of the built environment may positively or negatively affect older adults’ health behaviors. Therefore, this study aims to explore the relationship between older adults’ perceived built environments and health behaviors, which is the association between perceived built environments and older adults’ physical activity (PA) and social interactions. This is important for optimizing the community built environment and improving the quality of life of older adults.MethodsIn this study, a questionnaire was surveyed on 916 Chinese older adults aged 60 and above. The questionnaire was used to collect demographic information and social interaction from the participants, and the Physical Activity Neighborhood Environment Scale (PANES) and the Physical Activity Scale for the Elderly (PASE) were used to assess older adults’ subjective perceptions of the built environment in their neighborhoods and their levels of PA, respectively. In data analysis, ANOVA and chi-square tests were used to compare the significance of differences between groups, and multiple linear regression model were used to estimate the association between older adults’ perceived characteristics of the built environment and their PA and social interaction.ResultsAfter controlling for confounders such as gender, age, BMI, and education level, the multiple linear regression model showed that perceived destination accessibility, neighborhood infrastructure, aesthetic qualities, and neighborhood environment indices were significantly correlated with PA (β = 0.083 ~ 0.095, P < 0.05) and social interaction (β = 0.087 ~ 0.144, P < 0.05) among older adults. In addition, neighborhood safety (β = -0.084, P < 0.05), social environment (β = 0.091, P < 0.01), and street connectivity (β = 0.112, P < 0.001) were also strongly associated with older adults’ social interaction.ConclusionsDifferent perceived built environment attributes are correlated with the health behaviors of Chinese older adults to different degrees. This finding helps to guide community planning and construction, provides an empirical basis for improving health behaviors of older adults, and provides an important reference for building healthy communities for older adults and realizing comprehensive healthy development of older adults.Trial registrationThere was no trial registration for this study, but the study was approved by the Institutional Review Board of Tsinghua University (No. THU0120230196).

Study of readout system for 3He linear position sensitive detectors

This study introduces a readout system for 3He linear position-sensitive detectors (LPSDs), tailored for the Small Angle Neutron Scattering (SANS) spectrometer of the Compact Pulsed Hadron Source (CPHS) at Tsinghua University. Central to this system is the employment of a trapezoidal filter as the primary signal shaper, selected for its enhanced noise filtering capabilities and efficacy in mitigating ballistic deficit. Additionally, the integration of a digital CR filter aims to counteract baseline drift within trigger signals. This innovative architecture underwent validation via computer programs using experimental data, demonstrating superior performance in spatial resolution compared to conventional Gaussian filter-based approaches. Meanwhile, the improvement in spatial resolution comes with a narrower pulse width, promising a higher throughput at high count rates. When applied to a 16-tube detector module, the system achieved an average position resolution of 3.63 mm (FWHM) at the central region and 4.03 mm at the end regions. Furthermore, with a pusle width of 0.6 μs, the 96-tube detector array is promised to sustain a count rate over 1 Mcps.

Assemblies design and modeling analysis of a new fine mesh neutronics/thermal-hydraulics coupling benchmark for plate-type PWR core

In order to support the verification of neutronics/thermal-hydraulics coupling calculation method or simulation codes at the fine mesh for plate-type pressurized water reactor (PWR) with high parameters (which the ratio of power to mass flow rate is greater than 235 kW/kg, the core outlet enthalpy exceeds 1500 kJ/kg), a set of coupling calculation of plate-type PWR based on high parameters (COPHP) is design by Nuclear Power Institute of China (NPIC). Multiple industry research teams, including Tsinghua University, Xi'an Jiaotong University, and Huazhong University of Science and Technology, participated in the production of COPHP benchmark. This article provides a detailed explanation of the completed assembly design and modeling calculations, and provides the keff, pin-by-pin wise fine mesh relative power distribution, and deviation results calculated for 10 conditions of 6 assemblies using RMC, OpenMC, and KYLIN V2 software. The results show that: 1) when using the same cross-sectional library, the OpenMC calculation results are in good agreement with the RMC results. Taking ENDF/B-VII.1 as an example, the maximum deviation of keff in the entire burnup process of all assemblies is −157pcm, the maximum deviation of relative power is −1.13 %, and the maximum power weight error(PWE) is 0.226 %. 2) Compared between KYLIN V2 and the RMC by using ENDF/B-VII.1, the maximum deviation of keff is −468pcm, the maximum deviation of relative power is −1.49 %, and the maximum PWE is 0.316 % when calculating the standard assemblies with all control rod out(ARO) condition and two burnable poison assemblies. The maximum deviation of keff is −795pcm, the maximum deviation of relative power is 1.81 %, and the maximum PWE is 0.369 % when calculating the standard assemblies with all control rod inserted(ARI) conditions.

CharacterGen: Efficient 3D Character Generation from Single Images with Multi-View Pose Canonicalization

BNRist, Department of Computer Science and Technology, Tsinghua University, China In the field of digital content creation, generating high-quality 3D characters from single images is challenging, especially given the complexities of various body poses and the issues of self-occlusion and pose ambiguity. In this paper, we present CharacterGen, a framework developed to efficiently generate 3D characters. CharacterGen introduces a streamlined generation pipeline along with an image-conditioned multi-view diffusion model. This model effectively calibrates input poses to a canonical form while retaining key attributes of the input image, thereby addressing the challenges posed by diverse poses. A transformer-based, generalizable sparse-view reconstruction model is the other core component of our approach, facilitating the creation of detailed 3D models from multi-view images. We also adopt a texture-back-projection strategy to produce high-quality texture maps. Additionally, we have curated a dataset of anime characters, rendered in multiple poses and views, to train and evaluate our model. Our approach has been thoroughly evaluated through quantitative and qualitative experiments, showing its proficiency in generating 3D characters with high-quality shapes and textures, ready for downstream applications such as rigging and animation.

Exploration of the application of augmented reality technology for teaching spinal tumor's anatomy and surgical techniques.

Augmented reality (AR) technology is gradually being applied in surgical teaching as an innovative teaching method. Developing innovative teaching methods to replicate clinical theory and practical teaching scenarios, simulate preoperative planning and training for bone tumor surgery, and offer enhanced training opportunities for young physicians to acquire and apply clinical knowledge is a crucial concern that impacts the advancement of the discipline and the educational standards for young orthopedic physicians. This study explores the application effect of augmented reality technology in anatomy teaching and surgical clinical teaching for spinal tumor. The method utilizes virtual reality and augmented reality technology to present a spinal tumor model and the surgical process of percutaneous vertebroplasty. We conducted a random selection of 12 students forming into the augmented reality teaching group and 13 students forming into the traditional teaching group among the 8-year medical students from Peking Union Medical College and Tsinghua University, ensuring that the age and learning stage of the students in both groups were similar. Two groups of students were taught using traditional teaching methods and augmented reality technology-assisted teaching methods, respectively. A questionnaire survey was conducted after class to assess the quality of course instruction, student motivation in learning, their proficiency in anatomical structures, their comprehension of spinal tumor growth and metastasis, and their understanding and proficiency in percutaneous vertebroplasty. This study was the first to apply augmented reality technology in teaching, using spinal tumors and percutaneous vertebroplasty as examples, a head-mounted augmented reality device was used to create learning scenarios, presenting the complex three-dimensional spatial structure intuitively. The two groups of students differ significantly in their rating of teaching quality, enthusiasm for learning, knowledge of anatomical features, understanding of spinal trabecular structure, and understanding of steps in percutaneous vertebroplasty. The augmented reality technology-assisted teaching system demonstrates outstanding advantages. Augmented reality technology has great potential and broad prospects in teaching bone tumors, which can help improve the visualization, interactivity, and three-dimensional spatial sense of medical teaching in spinal tumor. The application and development prospects of using augmented reality technology for anatomy instruction, surgical teaching, and simulation training are extensive.

Monte Carlo Source Convergence Diagnosis Method and Thermal-Physics Coupling Method Based on Functional Expansion Tallies

In iterative Monte Carlo calculations for nuclear reactors, the inactive cycles should be calculated first to ensure that the source distribution is converged, and then the tallies of various parameters in the active cycles can begin. In order to acquire the mesh-free distribution of the fission source, this research proposes the functional expansion tallies (FET) source convergence diagnosis method in the Reactor Monte Carlo code, which is a self-developed stochastic simulation code maintained by the Reactor Engineering Analysis Laboratory of Tsinghua University. Due to the randomness in Monte Carlo calculations and the difficulty in determining the precise source convergence, this paper proposes a diagnostic tool based on function curve similarity and moving average, and proposes an online real-time source convergence diagnosis method. The FET online source convergence method can terminate the calculation of the inactive cycle in real time according to the convergence diagnostic tool; thus it can greatly decrease the calculation time. The precise and effective transfer of data between different meshes is a difficult issue of thermal and physical coupling. Converting two separate meshes and transferring the data are exceptionally difficult and complex tasks within the conventional nuclear thermal-physics coupling approach. By applying the FET method to nuclear thermal-physics coupling, the mesh-free continuous-space fission source distribution can be obtained, which is suitable for more complex meshes. Additionally, computational memory can be minimized by replacing (transforming) the data from numerous mesh power distribution data points with the coefficients of the function.