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Journal of Donghua University(English Edition) 2020年第4期37卷 286-292页

作者： LIU Huashan LI Jie YAO Fei College of Information Science and Technology Donghua UniversityShanghai 201620China Engineering Research center of Digitized Textile&Apparel Technology Ministry of EducationShanghai 201620China

Compared with the traditional three-phase star connection winding,the open-end winding permanent magnet synchronous motor(OW-PMSM)system with a common direct current(DC)bus has a zero-sequence circuit,which makes the common-mode voltage and the back electromotive force(EMF)harmonic generated by the inverters produce the zero-sequence current in the zero-sequence circuit,and the zero-sequence current has great influence on the operation efficiency and stability of the motor control system.A zero-sequence current suppression strategy is presented based on model predictive current control for *** the mathematical model of OW-PMSM to establish the predictive model and the zero-sequence circuit model,the common-mode voltage under different voltage vector combinations is fully considered during vector selection and action time *** zero-sequence loop constraints are established,so as to suppress the zero-sequence *** the end,the control strategy proposed in this paper is verified by simulation experiments.

关键词： open-end winding permanent magnet synchronous motor(OW-PMSM) zero-sequence current harmonic model predictive current control common-mode voltage

A volar skin excisional wound model for in situ evaluation of multiple-appendage regeneration and innervation

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Burns & Trauma 2023年第1期11卷 560-572页

作者： Huanhuan Gao Yiqiong Liu Ziwei Shi Hongliang Zhang Mengyang Wang Huating Chen Yan Li Shaifei Ji Jiangbing Xiang Wei Pi Laixian Zhou Yiyue Hong Lu Wu Aizhen Cai Xiaobing Fu Xiaoyan Sun Research center for Tissue Repair and Regeneration Affiliated to Medical Innovation Research Department and 4^(th)Medical center PLA General Hospital and PLA Medical CollegePLA Key Laboratory of Tissue Repair and Regenerative Medicine and Beijing Key Research Laboratory of Skin InjuryRepair and RegenerationResearch Unit of Trauma CareTissue Repair and RegenerationChinese Academy of Medical Sciences2019RU051Beijing 100048P.R.China Institute of Chemistry Chinese Academy of Sciences2 Beiyi StreetZhong guan cunBeijing 100190P.R.China Research Institute of General Surgery Department of General Surgerythe First Medical CenterPLA General Hospital28 Fu Xing RoadBeijing 100853P.R.China

Background:Promoting rapid wound healing with functional recovery of all skin appendages is the main goal of regenerative *** far current methodologies,including the commonly used back excisional wound model(BEWM)and paw skin scald wound model,are focused on assessing the regeneration of either hair follicles(HFs)or sweat glands(SwGs).How to achieve de novo appendage regeneration by synchronized evaluation of HFs,SwGs and sebaceous glands(SeGs)is still ***,we developed a volar skin excisional wound model(VEWM)that is suitable for examining cutaneous wound healing with multiple-appendage restoration,as well as innervation,providing a new research paradigm for the perfect regeneration of skin ***:Macroscopic observation,iodine-starch test,morphological staining and qRT-PCR anal-ysis were used to detect the existence of HFs,SwGs,SeGs and distribution of nerve fibres in the volar *** healing process monitoring,HE/Masson staining,fractal analysis and behavioral response assessment were performed to verify that VEWM could mimic the pathological process and outcomes of human scar formation and sensory function ***:HFs are limited to the *** are densely distributed in the footpads,scattered in the *** volar skin is richly *** wound area of the VEWM at 1,3,7 and 10 days after the operation is respectively 89.17%±2.52%,71.72%±3.79%,55.09%±4.94%and 35.74%±4.05%,and the final scar area accounts for 47.80%±6.22%of the initial *** the wound area of BEWM at 1,3,7 and 10 days after the operation are respectively 61.94%±5.34%,51.26%±4.89%,12.63%±2.86%and 6.14%±2.84%,and the final scar area accounts for 4.33%±2.67%of the initial *** analysis of the post-traumatic repair site for VEWM vs human was performed:lacunarity values,0.040±0.012 vs 0.038±0.014;fractal dimen-sion values,1.870±0.237 vs 1.903±*** nerve function of normal skin vs post-traumatic repair site was assessed

关键词： Wound healing Animal model Multiple appendages Innervation Regeneration evaluation Hair follicles Sweat gland Sebaceous gland

Analysis of Protective Relay Allocation and operation in 220 kV and Above AC Systems

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Electricity 2014年第5期25卷 1-7页

作者： Zhou Zexin Zhang Lie Lv Pengfei Shen Hua Wang Delin Li Yanfei Liu Yu Wu Chunliang Shen Xiaofan Yang Guosheng Wang Wenhuan Yao Xue Liu Yadong China Electric Power Research Institute National Power Dispatching and Control center

This paper provides a comprehensive summary of the scale, allocation and operation situation of relay protection equipment of the 220 kV and above AC systems run by the State Grid Corporation of China in 2012 and 2013. It also analyzes the changing trend of the relevant indices of relay protection during the five years from 2009 to 2013. At the same time, it analyzes in detail two typical relay malfunction events in 2012 and 2013.

关键词： power system relay protection statistics and analysis malfunction

An Improved Analytical Model for IEEE 802.11 Distributed Coordination Function under Finite Load

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International Journal of communications, Network and System Sciences 2009年第3期2卷 237-247页

作者： Rama Krishna CHALLA Saswat CHAKRABARTI Debasish DATTA Department of Computer Science National Institute of Technical Teachers’ Training and Research Chandigarh India Department of Electronics and Electrical communication Engineering Indian Institute of Technology Kharagpur India G. S. Sanyal School of Telecommunications Indian Institute of Technology Kharagpur India

In this paper, an improved analytical model for IEEE 802.11 distributed coordination function (DCF) under finite load is proposed by closely following the specifications given in IEEE 802.11 standard. The model is investigated in terms of channel throughput under perfect and slow Rayleigh fading channels. It is shown that the proposed model gives better insight into the operation of DCF.

关键词： IEEE 802.11 Markov DCF Wireless LANs Backoff Perfect Channel Rayleigh Fading Channel Saturation Finite Load Throughput

The Application of Modern Educational Technology in Modern Industrial Training

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The Application of Modern Educational Technology in Modern I...

CFD modeling and experiment of heat transfer in a tubular photo-bioreactor for photo-fermentation bio-hydrogen production

The 2011 International Conference on Advanced Materials and Information Technology Processing(AMITP 2011)

作者： WEN Xiqin Dongjing Wang Engineering Training center Huaihai Institute of Technology

For the sake of upgrading students' skills, this article interprets respectively the specific application of modern educational technologies from the four phases in modern industrial training: cognition, imitation, skills integration and refining. In the cognitive and directional phase, the training is aiming at inspiring learning motivation, understanding skills as well as the difficulty,gist, points of attention and the process of operation, in case errors occur. In the imitative stage, operating process should be made clear. Students should imitate teachers' operation so that the right visual image of standard operation will be transformed into students' own skills. In the integrative phase, according to the general operating process, all basic operations will be integrated together through the industrial training. Finally, in the skills refining stage, the modern educational technology will be introduced to realize the consistent Human-Computer Interaction practice to improve operation and teaching effect.

关键词： Modern industrial training,Modern educational technologies,Cognition Imitation,Integration,Skills training

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International Journal of Agricultural and Biological Engineering 2017年第1期10卷 209-217页

作者： Zhang Zhiping Zhang Quanguo Yue Jianzhi Li Lianhao Zhang Tian Liu Zhengbai Key Laboratory of New Materials and Facilities for Rural Renewable Energy Ministry of AgricultureCollege of Mechanical&Electrical engineeringHenan Agricultural UniversityZhengzhou 450002China Collaborative Innovation center of Biomass Energy Zhengzhou 450002China

Temperature is one of the most important parameters that need to be controlled in photo-fermentation bio-hydrogen production(PFHP)*** the high temperature and big temperature fluctuation have adverse impacts on bio-hydrogen yield,the system numerical simulation based on the operating conditions and environmental factors is *** research focused on the investigation of heat transfer properties of the PFHP *** hydrolysate from agricultural residues was taken as substrate,and up-flow tubular photo-bioreactor was adopted for *** inside the photo-bioreactor were *** experimental design and computational modeling for the determination of the heat transfer behavior in tubular photo-bioreactor was *** balance analysis was conducted to determine the energy efficiency,and optimize the operation parameters in order to obtain higher energy *** commercial software FLUENT was also adopted in order to predict the transient temperature distribution in the *** results showed that mathematical and computational modeling method has a clear potential for improving the performance of photo-bioreactor in the process of ***-flow tubular bioreactor has tiny temperature fluctuant,and is suitable for PFHP.

关键词： photo-fermentation bio-hydrogen production(PFHP) up-flow tubular photo-bioreactor heat transfer temperature distribution numerical simulation

Dynamic Fracture Toughness of Armour Grade Quenched and Tempered Steel Joints Fabricated Using Low Hydrogen Ferritic Fillers

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Journal of Iron and Steel Research International 2010年第5期17卷 51-56页

作者： G Magudeeswaran V Balasubramanian S Sathyanarayanan G Madhusudhan Reddy A Moitra S Venugopal G Sasikala Department of Mechanical Engineering Pannaikkadu Veerammal Paramasivam College of Engineering andTechnology for Women Department of Manufacturing Engineering Annamalai University Materials Mechanics Section Indira Gandhi Center for Atomic Research Metal JoiningSection Defence Metallurgical Research Laboratory

The armour grade quenched and tempered steel joints fabricated using low hydrogen ferritic steel （LHF） filler exhibited superior joint efficiency owing to preferential ferrite microstructure in the welds and also they offered required resistance to HIC. However, the combat vehicles used in military operations will be required to operate under a wide range of road conditions ranging from first class to cross country. Structural components in combat vehicles are subjected to dynamic loading with high strain rates during operation. Stress loadings within the vehicle hull of these vehicles are expected to fluctuate considerably and structural cracking especially in welds during the service life of these vehicles can lead to catastrophic failures. Under these conditions, fracture behaviour of high strain rate sensitive structural steels can be better understood by dynamic fracture toughness （K1d）. Hence, an attempt was made to study dynamic fracture toughness of the armour grade quenched and tempered steel and their welds fabricated using LHF consumables. The experimental results indicate that the K1d values of the joints fabricated by shielded metal arc welding （SMAW） are higher than those of the joints fabricated using flux cored arc welding （FCAW） process.

关键词： quenched steel tempered steel low hydrogen ferritic steel dynamic fracture toughness

Effects of Total Intravenous Anesthesia and Static Aspiration Combined General Anesthesia on Postoperative Cognitive Function and Psychological State of Elderly Patients with Esophageal Cancer

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Open Journal of Anesthesiology 2022年第5期12卷 161-167页

作者： Lan Xie Chuanzhen Li Department of Anesthesiology Sun Yat-sen University Cancer Center Guangzhou China

Objective: To compare the effects of total intravenous anesthesia and static aspiration combined general anesthesia on postoperative cognitive function and psychological state of elderly esophageal cancer patients. Methods: From July 2020 to April 2021, 180 elderly patients who underwent radical esophageal cancer surgery in our hospital were randomly divided into 90 cases in the control group and 90 in the observation group. The control group used static aspiration compound general anesthesia, and the patients in the observation group used intravenous anesthesia to compare the cognitive function and psychological state of the two groups of patients. Results: There was no statistical difference in the cognitive function score of patients in the observation group 30 minutes before anesthesia, 1 h and 24 hours after anesthesia compared with that in the control group, P > 0.05;there was no statistical difference between the Hamilton Anxiety Scale (HAMA) scores 30 minutes before and 24 hours after anesthesia in the observation group compared with the control group, P > 0.05;the cognitive function score of patients in the observation group of 4 h after surgery and 12 h after operation was significantly higher than that of the control group;the HAMA scores of patients in the observation group of 1 h, 4 h and 12 h after surgery were significantly lower than that of the control group, P Conclusion: The application of total intravenous anesthesia in elderly patients with esophageal cancer surgery can reduce the impact of anesthesia on their cognitive function and psychological state, which is worth popularizing and applying in clinical practice.

关键词： Total Intravenous Anesthesia Static Aspiration Combined General Anesthesia Esophageal Cancer Elderly Surgery Postoperative Cognitive Function Psychological State

Acute diffuse peritonitis secondary to a seminal vesicle abscess:A case report

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World Journal of Clinical Cases 2023年第3期11卷 645-654页

作者： Kun Li Nan-Bin Liu Jiang-Xi Liu Quan-Ning Chen Bao-Min Shi Department of General Surgery Tongji Hospital of Tongji UniversityShanghai 200065China National and Local Joint Engineering Research center of Biodiagnosis and Biotherapy The Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710000Shaanxi ProvinceChina

BACKGROUND Seminal vesicle abscess(SVA)is the manifestation of a relatively rare urinary system *** response to urinary system inflammation,an abscess forms in special ***,acute diffuse peritonitis(ADP)induced by SVA is *** SUMMARY We report a case of a left SVA in a male patient complicated with pelvic abscess,ADP,multiple organ dysfunction syndrome,infectious shock,bacteremia,and acute appendiceal extraserous suppurative inflammation as a result of a long-term indwelling urinary *** patient received a course of morinidazole+cefminol antibiotics but showed no obvious relief,so the perineal SVA underwent puncture drainage and abdominal abscess drainage+appendectomy was *** operations were *** the operation,anti-infection,anti-shock,and nutritional support treatments were continued and various laboratory indicators were regularly *** patient was discharged from the hospital after *** disease is a challenge for the clinician because of the unusual spreading path of the ***,appropriate intervention and adequate drainage of abdominal and pelvic lesions are necessary,especially when the primary focus cannot be *** The etiology of ADP varies,but acute peritonitis secondary to SVA is very *** this patient,the left SVA not only affected the adjacent prostate and bladder but also spread retrogradely through the vas deferens,forming a pelvic abscess in the loose tissues of the extraperitoneal fascia *** involving the peritoneal layer led to ascites and pus accumulation in the abdominal cavity,and appendix involvement led to extraserous suppurative *** clinical practice,surgeons need to consider the results of various laboratory tests and imaging examinations to make comprehensive judgments involving the diagnosis and treatment plan.

关键词： Seminal vesicle abscess Acute diffuse peritonitis Acute appendicitis Multiple organ dysfunction syndrome Case report

Design and test of a novel crawler-type multi-channel air-assisted orchard sprayer

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International Journal of Agricultural and Biological Engineering 2020年第6期13卷 60-67页

作者： Wei Qiu Xiaolong Li Chongchong Li Weimin Ding Xiaolan Lv Yande Liu College of Engineering Nanjing Agricultural UniversityNanjing 210031China Jiangsu Academy of Agricultural Sciences Nanjing 210000China Co-Innovation center of the Intelligent Management and Equipment for Orchard on the Hilly Land in South China Nanchang 330013China

In order to solve the problem of poor traveling stability and excessive pesticide application during plant protection operations in hilly orchards,a novel crawler-type multi-channel air-assisted sprayer that is particularly appropriate for hilly orchards was designed in this *** anti-rolling requirements and the orchard environment in hilly areas,this study selected limits for uphill and downhill rolling angles as well as the transverse rolling angle as the evaluation indexes for determining both the layout and parameter settings of the *** to freely submerged jets and the requirements in plant protection operation,a multi-channel air-assisted system was *** test results showed that the anti-rolling performance and the designed air-assisted system were *** 2 m from the longitudinal center plane of the sprayer,the airflow exhibited wavy distribution patterns under different parameter combinations since the four streams of the airflow were not thoroughly intersected and *** 3 m from the longitudinal center plane of the sprayer,the jet was ejected at great velocity but underwent rapid attenuation;the airflow velocity in most areas barely satisfied the requirements for plant protection *** addition,different air outlet layout schemes led to significant differences in the spatial distribution of the airflow *** with a traditional air-assisted sprayer,using the developed multi-channel air-assisted sprayer enhanced the droplet coverage uniformity by 19.4%,and the mean droplet deposition in the front,middle,and rear of the canopy was enhanced by 32.9%,50.3%,and 78.1%,respectively,while reducing ground deposition and air drift by 26.8%.

关键词： fan dual-flow-channel plant protection air-assisted test