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Characteristics of Bi-2223 HTS Tapes Under Short-Circuit Current Impacts in Hybrid Energy Transmission Pipelines

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 736-745页

作者： Yuguang sun Chao Yin Weizhen li Xinyang li Xiaohua Jiang Department of Electric Engineering Tsinghua UniversityBeijing 100084China

A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.

关键词： Bi-2223 high-temperature superconducting(HTS)tape critical current hybrid energy transmission pipeline liquefied natural gas(LNG)cooling temperature short-circuit current impact characteristics

Rapid Simultaneous Determination of Four Ganoderic Acids in Ganoderma(Chinese Name:lingzhi)by Direct Infusion-Multiple Reaction Monitoring Cubed

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Journal of Analysis and Testing 2024年第1期8卷 52-62页

作者： Nian Wu bo Peng Ting li Pengfei Tu Shengpeng Wang bo li Wenjing liu Yuelin Song Modern Research Center for Traditional Chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China Amway(China)botanical Research Center Wuxi 214011China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipa 999078China Amway(Shanghai)Innovation&Science Co. LtdShanghai 201508China School of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China

Attributing to the rapid demand expansion for the edible medicinal materials in the market,the limited throughput of highperformance liquid chromatography-multiple reaction monitoring(HPLC-MRM)cannot fully address the measurement workload for a huge number of testing ***,it is urgent to pursue more efficient approaches for the quality *** of the greater selectivity of MRM cubed(MRM^(3))over MRM,there might be a chance to omit the time-intensive LC *** current study,we attempted to develop a direct infusion(DI)-MRM^(3) program,and the applicability was thereafter assessed through simultaneous determination of four ganoderic acids(GAs)in one of the most famous tonic herbal medicines namely Ganoderma(Chinese name:lingzhi).Primary parameters such as Q1>Q3>QliT ion transitions,collision energy(CE),and excitation energy were optimized by programming online energy-resolved mass spectrometry with authentic compounds.A single DI-MRM measurement merely costed four minutes,and in spite of the wide occurrences of isomers,satisfactory selectivity was *** validation assays demonstrated the method to be sensitive,precise,accurate,and *** quantitative results from DI-MRM^(3) were also justified by conducting LC-MRM measurements in *** differences occurred for the content patterns between the two original sources namely Ganoderma lucidum and ***,and,moreover,either cultivar or harvest time showed dramatical influence on the quantitative features of the four targeted *** importantly,DI-MRM3 is a meaningful analytical option for rapid quantitative analysis of herbal medicines,because of the comparable reliability,nonetheless,less consumptions of both measurement time and solvent,compared with LC-MRM.

关键词： Direct infusion Multiple reaction monitoring cubed High-throughput quantitative analysis Ganoderic acids Ganoderma

Autonomous relative optical navigation based on unified modeling of external systematic errors

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Chinese Journal of Aeronautics 2024年第3期37卷 282-289页

作者： Dayi WANG bowen sun Maodeng li Jiaxing li Haiyin ZHOU Beijing Institute of Spacecraft System Engineering Beijing 100191China College of Sciences National University of Defense TechnologyChangsha 410073China National Key Laboratory of Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100191China

To solve the problem that external systematic errors of the optical camera cannot be fully estimated due to limited computing resources,a unified dimensionality reduction representation method for the external systematic errors of the optical camera is proposed,and autonomous relative optical navigation is *** camera translational and misalignment errors are converted into a three-dimensional rotation error,whose differential model can be established through specific attitude control and appropriate ***,the rotation error and the relative motion state are jointly estimated in an augmented Kalman filter *** with the traditional method that estimates the camera translational and misalignment errors,the proposed method reduces the computational complexity in that the estimated state dimension is ***,as demonstrated by numerical simulation,the estimation accuracy is improved significantly.

关键词： Unified model Systematic errors Optical navigation Observability analysis Calibration

Exploring changes of precipitation extremes under climate change through global variable-resolution modeling

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Science Bulletin 2024年第2期69卷 237-247页

作者： Wei sun Jian li Rucong Yu Nina li Yi Zhang State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China National Meteorological Center China Meteorological AdministrationBeijing 100081China 2035 Future Laboratory PIESAT Information Technology Co.Ltd.Beijing 100105China

Understanding the responses of precipitation extremes to global climate change remains limited owing to their poor representations in models and complicated interactions with multi-scale *** we take the record-breaking precipitation over China in 2021 as an example,and study its changes under three different climate scenarios through a developed pseudo-global-warming(PGW)experimental framework with 60-3 km variable-resolution global ensemble *** to the present climate,the precipitation extreme under a warmer(cooler)climate increased(decreased)in intensity,coverage,and total amount at a range of 24.3%-37.8%(18.7%-56.1%).With the help of the proposed PGW experimental framework,we further reveal the impacts of the multi-scale system interactions in climate change on the precipitation *** the warmer climate,large-scale water vapor transport converged from double typhoons and the subtropical high marched into central China,enhancing the convective energy and instability on the leading edge of the transport *** a result,the mesoscale convective system(Mcs)that directly contributed to the precipitation extreme became stronger than that in the present *** the contrary,the cooler climate displayed opposite changing characteristics relative to the warmer climate,ranging from the large-scale systems to local environments and to the *** summary,our study provides a promising approach to scientifically assess the response of precipitation extremes to climate change,making it feasible to perform ensemble simulations while investigating the multi-scale system interactions over the globe.

关键词： Precipitation extreme Climate change Pseudo-global-warming experiment Variable-resolution modeling Multi-scale system interaction

Consistency of Tropospheric Water Vapor between Reanalyses and Himawari-8/AHI Measurements over East Asia

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Advances in Atmospheric Sciences 2024年第1期41卷 19-38页

作者： Di DI Jun li Yunheng XUE Min MIN bo li Zhenglong li Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory for Aerosol-Cloud-Precipitation China Meteorological AdministrationSchool of Atmospheric PhysicsNanjing University of Information Science and TechnologyNanjing 210044China FYSIC National Satellite Meteorological CenterChina Meteorological AdministrationBeijing 100081China Chengdu University of Information Science and Technology Chengdu 610225China School of Atmospheric Sciences and Guangdong Province Key laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University and Southern Laboratory of Ocean Science and EngineeringZhuhai 519082China Cooperative Institute for Meteorological Satellite Studies University of Wisconsin–MadisonMadison WI 53706WisconsinUSA Wuxi University Wuxi 214105China

High spatiotemporal resolution radiances from the advanced imagers onboard the new generation of geostationary weather satellites provide a unique opportunity to evaluate the abilities of various reanalysis datasets to depict multilayer tropospheric water vapor(WV),thereby enhancing our understanding of the deficiencies of WV in reanalysis *** on daily measurements from the Advanced Himawari Imager(AHI)onboard the Himawari-8 satellite in 2016,the bias features of multilayer WV from six reanalysis datasets over East Asia are thoroughly *** assessments show that wet biases exist in the upper troposphere in all six reanalysis datasets;in particular,these biases are much larger in ***,we find better depictions of WV in the middle troposphere than in the upper *** accuracy of WV in the ERA5 dataset is the highest,in terms of the bias magnitude,dispersion,and pattern *** characteristics of the WV bias over the Tibetan Plateau are significantly different from those over other parts of East *** addition,the reanalysis datasets all capture the shift of the subtropical high very well,with ERA5 performing better overall.

关键词： AHI reanalysis dataset multilayer water vapor assessment radiative transfer model

Road sub-surface defect detection based on gprMax forward simulation-sample generation and Swin Transformer-YOLOX

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 334-349页

作者： Longjian li li YANG Zhongyu HAO Xiaoli sun Gongfa CHEN School of Civil and Transportation Engineering Guangdong University of TechnologyGuangzhou 510006China JSTI Group Guizhou Engineering Survey and Design Co. Ltd.Guangzhou 510800China Guangzhou Municipal Engineering Testing Co. Ltd.Guangzhou 510520China

Training samples for deep learning networks are typically obtained through various field experiments,which require significant manpower,resource and time ***,it is possible to utilize simulated data to augment the training *** this paper,by comparing the actual experimental model with the simulated model generated by the gprMax[1]forward simulation method,the feasibility of obtaining simulated samples through gprMax simulation is ***,the samples generated by gprMax forward simulation are used for training the network to detect objects in existing real *** the same time,aiming at the detection and intelligent recognition of road sub-surface defects,the Swin-YOLOX algorithm is introduced,and the excellence of the detection network,which is improved by augmenting the simulated samples with real samples,is further *** comparing the prediction performance of the object detection models,it is observed that the model trained with mixed samples achieved a recall of 94.74%and a mean average precision(maP)of 97.71%,surpassing the model trained only on real samples by 12.95%and 15.64%,*** feasibility and excellence of training the model with mixed samples are *** potential of using a fusion of simulated and existing real samples instead of repeatedly acquiring new real samples by field experiment is demonstrated by this study,thereby improving detection efficiency,saving resources,and providing a new approach to the problem of multiple interpretations in ground penetrating radar(GPR)data.

关键词： ground penetrating radar gprMax forward modeling sample generation Swin-YOLOX object detection

Comparison of Laparoscopy-Assisted Gastrectomy and Conventional Open Gastrectomy with the Same Procedure in Early Distal Gastric Cancer

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Journal of Cancer Therapy 2013年第1期4卷 1-5页

作者： li-bo sun Zhen-bo Shu Yun-Xin Zhang Da-Yong Ding Yong-Chao li Department of Gastrointestinal Surgery China-Japan Union Hospital Jilin University Changchun China.

Introduction: Laparoscopy-assisted gastrectomy (LAG) for early gastric cancer (EGC) was considered as a treatment with many advantages due to the application of laparoscopic equipment. The aim of this study was to compare the effect of use of laparoscopic equipment in blood loss, the number of harvested lymph nodes (HLNs), and complications between LAG and open gastrectomy (OG) for EGC. Methods: Patients received surgical treatment for early distal gastric cancer (EDGC) were retrospectively reviewed. Patients were classified into three groups by different operation methods: traditional open distal gastrectomy (ODG) group, laparoscopy-assisted distal gastrectomy (LADG) group, and open distal gastrectomy with assistance of laparoscopic equipment (ODGA) group. Results: Altogether 65 patients with EDGC received surgical treatment, including 20 cases of ODG, 22 of LADG, and 23 of ODGA. No lymph node metastasis was found in all patients. 25 (38.5%) postoperative confirmed T2 were misdiagnosed as T1 preoperatively. Compared with ODG group, the blood loss was significantly reduced in LADG and ODGA groups (106.4 ± 46.0;and 73.3 ± 35.7 ml vs. 250.5 ± 65.1 ml respectively;P 0.01), but the operation time was significantly longer in these groups (231.0 ± 34.5, and 222.5 ± 42.6 min vs. 128.5 ± 22.3 min respectively;P 0.01). No difference was found in the blood loss, operation time, the number of harvested lymph nodes and the types of gastrointestinal continuity reconstruction between LADG and ODGA groups. No difference was found in the postoperative complications among the three groups. Conclusions: Laparoscopic equipment might be the key factor in the reduction of blood loss and the delay of operation time for LADG. Application of laparoscopic equipment in open gastrectomy can be used as a training method to shorten learning curve for LAG beginners.

关键词： Laparoscopic Assisted Gastrectomy Early Gastric Cancer Open Gastrecomy Laparoscopic Equipment

A Fast Startup Crystal Oscillator with Digital SAR-AFC Based Two-Step Injection

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Chinese Journal of Electronics 2024年第5期33卷 1147-1153页

作者： bo ZHOU Yifan li Zuhang WANG School of Integrated Circuits and Electronics Beijing Institute of Technology

Crystal oscillators（XOs） provide a high-precision reference frequency but have a long startup time,which severely increases the average power consumption in duty-cycled *** paper proposes a fully-digital low-cost two-step injection technique,by using a successive approximation register（SAR） based auto frequency control（AFC） loop,to speed up the startup behavior of XOs.A theoretical analysis is carried out to determine the optimum injection time and design low-power *** in a 65 nm CMOS process,the proposed 12 MHz fast startup XO occupies an active area of 0.02 mm2and achieves a startup time less than 35 μ*** XO power consumption in the steady state is 40 μW from a 1.0-V supply,with a startup energy of 17.2 nJ.

关键词： Time-frequency analysis Power demand Power measurement Crystals Time measurement Steady-state Registers Crystal oscillator Two-step injection Successive approximation register Auto frequency control Fully-digital Fast startup ENERGY

Metal-based cathode catalysts for electrocatalytic ORR in microbial fuel cells:A review

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Chinese Chemical Letters 2024年第5期35卷 85-96页

作者： Yaxin sun Huiyu li Shiquan Guo Congju li School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

Microbial fuel cells(MFCs)have a simple structure and excellent pollutant treatment and power generation ***,the slow kinetics of the oxygen reduction reaction(ORR)at the MFC cathode limit power *** electrochemical performance of MFCs can be improved through *** far,metal-based catalysts have shown astonishing results in the field of electrocatalysis,enabling MFC devices to demonstrate power generation capabilities comparable to those of Pt,thus showing enormous *** article reviews the research progress of meta-based MFC cathode ORR catalysts,including the ORR reaction mechanism of MFC,different types of catalysts,and preparation *** catalytic effects of different catalysts in MFC are compared and *** discussing the practical application and expanded manufacturing of catalysts,we summarize the key challenges that must be addressed when using metal-based catalysts in MFC,with the aim of providing a scientific direction for the future development of advanced materials.

关键词： Microbial fuel cells Metal-based cathode catalysts Oxygen reduction reaction Noble metal catalysts MOFs M-N-C Single-atom Transition metal oxides