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An optimization of injecting system in die casting 被引量:1
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作者 Wei WU Yan ZHANG +1 位作者 Feng LI ZHENG Liu 《China Foundry》 SCIE CAS 2005年第2期112-116,共5页
After many years of development, die casting technology of metallic materials has been matured. In this paper,the lower-support and its injecting system were created with commercial software. And then the simulation s... After many years of development, die casting technology of metallic materials has been matured. In this paper,the lower-support and its injecting system were created with commercial software. And then the simulation softwareFLOW3D was applied to study the flow behavior of the melt during injection filling process. Both temperature field anddefect distribution were simulated. Based on these results, the better injecting system with two additional overflows wasadopted. 展开更多
关键词 COMPUTER simulation INJECTION DIE CASTING
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Single event effects evaluation on convolution neural network in Xilinx 28 nm system on chip
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作者 赵旭 杜雪成 +4 位作者 熊旭 马超 杨卫涛 郑波 周超 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期638-644,共7页
Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic partic... Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic particles, such as heavy ions, protons, and alpha particles, can induce single event effects(SEEs) that lead CNNs to malfunction and can significantly impact the reliability of a CNN system. In this paper, the MNIST CNN system was constructed based on a 28 nm systemon-chip(SoC), and then an alpha particle irradiation experiment and fault injection were applied to evaluate the SEE of the CNN system. Various types of soft errors in the CNN system have been detected, and the SEE cross sections have been calculated. Furthermore, the mechanisms behind some soft errors have been explained. This research will provide technical support for the design of radiation-resistant artificial intelligence chips. 展开更多
关键词 single event effects convolutional neural networks alpha particle system on chip fault injection
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Conservative management of spinal pathology with autologous conditioned serum: A systematic review of the literature
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作者 Christian J Rajkovic Matthew L Merckling +6 位作者 Alyssa W Lee Galadu Subah Aryan Malhotra Zachary D Thomas Sabrina L Zeller John V Wainwright Merritt D Kinon 《World Journal of Orthopedics》 2024年第9期870-881,共12页
BACKGROUND Chronic inflammatory pain is associated with increased expression of interleukin(IL)-1,an inflammatory cytokine,and activity on its receptor(IL-1R).In response,the body produces IL-1R antagonist(IL-1Ra)to r... BACKGROUND Chronic inflammatory pain is associated with increased expression of interleukin(IL)-1,an inflammatory cytokine,and activity on its receptor(IL-1R).In response,the body produces IL-1R antagonist(IL-1Ra)to reduce this signaling.Autologous conditioned serum(ACS)is the only biologic therapy for spinal pathologies that enhances the action of endogenous IL-1Ra reserves to improve symptoms.This systematic review investigates the effectiveness of ACS in treating pain and dis-ability caused by spinal pathologies.AIM To evaluate the use of ACS as a conservative management option for spinal path-ology.METHODS A systematic review of PubMed/Medline was performed to identify studies inve-stigating administration of ACS for treatment of any spinal pathology.RESULTS Six articles were included,comprising 684 patients treated with epidural(n=133)or transforaminal(n=551)ACS injections.Patients had an average age of 54.0 years with slight female predominance(53.2%).The lumbar spine was most com-monly treated,with 567 patients(82.9%)receiving injections for lumbar radicu-lopathy(n=67),degenerative disc disease(DDD)(n=372),or spinal stenosis(n=128);cervical injections were performed in 109 patients(15.9%).Mean(SD)follow-up was 21.7(4.8)weeks from first ACS injection.All studies investigating mecha-nical lumbar and lumbar or cervical radicular pain reported significant pain re-duction at final follow-up compared to baseline.ACS achieved comparable or su-perior results to lumbar epidural steroid injections.Adverse events were reported in 21 patients(3.1%),with no serious adverse events.CONCLUSION ACS injection is a safe and effective intervention for pain reduction in many spinal pathologies,including cervical and lumbar radiculopathies. 展开更多
关键词 SPINE Autologous conditioned serum Orthokine Regenokine Epidural steroid injection INTERLEUKIN-1 Inter-leukin-1 receptor antagonist
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Security Vulnerability Analyses of Large Language Models (LLMs) through Extension of the Common Vulnerability Scoring System (CVSS) Framework
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作者 Alicia Biju Vishnupriya Ramesh Vijay K. Madisetti 《Journal of Software Engineering and Applications》 2024年第5期340-358,共19页
Large Language Models (LLMs) have revolutionized Generative Artificial Intelligence (GenAI) tasks, becoming an integral part of various applications in society, including text generation, translation, summarization, a... Large Language Models (LLMs) have revolutionized Generative Artificial Intelligence (GenAI) tasks, becoming an integral part of various applications in society, including text generation, translation, summarization, and more. However, their widespread usage emphasizes the critical need to enhance their security posture to ensure the integrity and reliability of their outputs and minimize harmful effects. Prompt injections and training data poisoning attacks are two of the most prominent vulnerabilities in LLMs, which could potentially lead to unpredictable and undesirable behaviors, such as biased outputs, misinformation propagation, and even malicious content generation. The Common Vulnerability Scoring System (CVSS) framework provides a standardized approach to capturing the principal characteristics of vulnerabilities, facilitating a deeper understanding of their severity within the security and AI communities. By extending the current CVSS framework, we generate scores for these vulnerabilities such that organizations can prioritize mitigation efforts, allocate resources effectively, and implement targeted security measures to defend against potential risks. 展开更多
关键词 Common Vulnerability Scoring system (CVSS) Large Language Models (LLMs) DALL-E Prompt Injections Training Data Poisoning CVSS Metrics
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Flow injection chemiluminescence determination of meloxicam using potassium permanganate and formaldehyde system 被引量:1
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作者 贾宝秀 曹明亮 +3 位作者 刘彩红 李玉琴 李珂 齐永秀 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第1期35-40,共6页
A simple, rapid and sensitive flow injection chemiluminescence (FI-CL) method has been developed for the determination of meloxicam. The method is based on the CL-emitting reaction between meloxicam and potassium pe... A simple, rapid and sensitive flow injection chemiluminescence (FI-CL) method has been developed for the determination of meloxicam. The method is based on the CL-emitting reaction between meloxicam and potassium permanganate in a hydrochloric acid medium, enhanced by formaldehyde (HCHO). Under optimum conditions, calibration curve over the range of 1.0-20.0μg/mL was obtained. The proposed method was successfully applied to the determination of meloxicam in capsules with no evi- dence of interference from common excipients. The detection limit of this method was 25.6 ng/mL. The relative standard deviation was 2.1% for 10.0 μg/mL meloxicam. The sample throughput was found to be 120 samples/h. 展开更多
关键词 MELOXICAM Flow injection chemiluminescence FORMALDEHYDE Pharmaceutical analysis
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Preliminary Study on Transgenesis by Injecting Exogenous DNA into Zygote Cytoplasm of Buffalo
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作者 陈自洪 崔奎青 +4 位作者 孟凡丽 刘玉兵 王丹 陆凤花 石德顺 《Agricultural Science & Technology》 CAS 2012年第6期1167-1170,1174,共5页
[Objective] This study aimed to investigate the feasibility of transgenesis by injecting exogenous DNA into zygote cytoplasm of Buffalo. [Method] Buffalo oocytes were randomly divided into two groups 20-22 h after in ... [Objective] This study aimed to investigate the feasibility of transgenesis by injecting exogenous DNA into zygote cytoplasm of Buffalo. [Method] Buffalo oocytes were randomly divided into two groups 20-22 h after in vitro maturation. One group of oocytes was introduced with about 7.5 pl of 50 μg/ml DNA solution containing linear EGFP fragment by cytoplasmic injection 7-10 h or 18-20 h after in vitro fertilization (IVF); the other group of oocytes was introduced with mixture of a single buffalo sperm and about 7.5 pl of 50 μg/ml DNA solution containing linear EGFP fragment by cytoplasmic injection (generally called ICSI-Mediated Gene Transfer, ICSI-Tr). Expression of exogenous DNA was observed and recorded during the process of embryonic development. [Result] Early embryonic gene expression efficiency and blastocyst gene expression efficiency in IVF injection group showed no significant difference compared with that in ICSI-Tr group (P0.05). In addition, the cleavage rate and early embryonic gene expression efficiency in IVF injection group were significantly higher with injection at 7-10 h post IVF than that at 18-20 h post IVF (P0.05). [Conclusion] These results indicate that transgenic buffalo embryos can be generated by injecting exogenous DNA into cytoplasm of IVF oocytes, and the optimal injection time is 7-10 h post IVF. 展开更多
关键词 BUFFALO ZYGOTE Cytoplasmic injection TRANSGENESIS
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Rectifier Configurations Based on Harmonic Injecting and Counteracting Principle
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作者 何丹 戴先中 +1 位作者 肖仁良 徐以荣 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期81-88,共8页
On the basis of detailed analysis of a novel harmonic counteracting method which can be used to effectively compensate the supply line harmonic currents of a passive single phase diode bridge rectifier, this paper pr... On the basis of detailed analysis of a novel harmonic counteracting method which can be used to effectively compensate the supply line harmonic currents of a passive single phase diode bridge rectifier, this paper presents two simpler single phase diode bridge rectifier configurations and their alternatives which can achieve low supply line current THD(total harmonic distortion) too. Moreover, this paper also proposes a few passive hamonic counteracting networks for multi single phase rectifiers which are connected in parallel. 展开更多
关键词 single phase rectifier harmonic compensation current injection THD
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Refractory lipoatrophy treated with autologous whole blood injection:A case report
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作者 Wonnam Kim Jun Su Park En Hyung Kim 《World Journal of Clinical Cases》 SCIE 2025年第2期33-38,共6页
BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resol... BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resolve,several treatment options have been suggested for this condition.CASE SUMMARY In this paper,we report a case of corticosteroid injection induced lipoatrophy treated with autologous whole blood(AWB)injection,as the condition had been unresponsive to fractional laser therapy.A 29-year-old female patient visited the dermatology clinic complaining of skin depression on her right buttock area,which had appeared six months earlier.There had been only subtle improvement at the margins after fractional CO_(2) laser treatment;therefore,after obtaining informed consent from the patient,AWB treatment was initiated.One month after the first AWB injection,the size and depth of the lesion had noticeably improved,and a slight improvement was also observed in discoloration.CONCLUSION Close observation is the initial treatment of choice for steroid induced skin atrophy;however,for patients in need of immediate cosmetic improvement,AWB injection may be a safe and cost-effective alternative. 展开更多
关键词 ATROPHY CORTICOSTEROID Subcutaneous fat Autologous whole blood injection Laser therapy Case report
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The effect of subcutaneous injection duration on patients receiving low-molecular-weight heparin:Evidence from a systematic review 被引量:13
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作者 Li-juan Yi Ting Shuai +3 位作者 Xu Tian Zi Zeng Li Ma Guo-min Song 《International Journal of Nursing Sciences》 2016年第1期79-88,共10页
To assess the effect of the injection duration of subcutaneous low-molecular-weight heparin(LMWH)on pain and bruising in patients.Randomized controlled trials and quasiexperimental studies were searched for in four el... To assess the effect of the injection duration of subcutaneous low-molecular-weight heparin(LMWH)on pain and bruising in patients.Randomized controlled trials and quasiexperimental studies were searched for in four electronic databases.The pooled effect size was expressed as relative risk(RR)andmeandifference(MD)with95%confidence intervals(CI)for dichotomous and continuous data.Cochrane Q and p value were used to assess heterogeneity and the I2 statistic was adopted to quantify the level.Finally,eight studies involving a total of 532 participants met our inclusion criteria.The slow(30 second)injection was associated with a reduction in pain intensity and duration,and lower bruising occurrence at 48-72 hours and 48 hours post injection.The bruising area was also smaller at 48 hours and 60 hours post injection.Nodifferenceswere identified betweenthe slowand fast(10 second)injectionin bruising area and bruising occurrence at 24 hours and 60 hours post injection.With present evidences,slow injection of LMWH is beneficial to the patient's well being,but further studies to identify the feasibility and standardization of the technique is recommended. 展开更多
关键词 HEPARIN INJECTIONS SUBCUTANEOUS Injection duration systematic review META-ANALYSIS
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A systematic review and meta-analysis of the Chinese literature for the treatment of achalasia 被引量:14
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作者 Lan Wang You-Ming Li Lan Li Chao-Hui Yu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第38期5900-5906,共7页
AIM: To evaluate the effect of different approaches in the treatment of achalasia in China. METHODS: We performed a systematic review and meta-analysis of Chinese literature by searching the Chinese Biomedical Databas... AIM: To evaluate the effect of different approaches in the treatment of achalasia in China. METHODS: We performed a systematic review and meta-analysis of Chinese literature by searching the Chinese Biomedical Database and Chinese scientific Journals database (up to March 2008). All cohort studies (controlled or uncontrolled) in which the patients were observed for more than a year were reviewed in detail. Dichotomous outcomes were reported as relative risks (RR) with 95% confidence interval (CI) for controlled trials. The efficacy in uncontrolled trials was assessed by a pooled estimate of response rate with individual studies weighted in proportion to the sample size. RESULTS: Seven controlled trials compared the effect of botulinum toxin injection (BoTx) with pneumatic dilation (PD). PD was superior to BoTx [65.2% vs 45.3%; RR 1.47 (95% CI 1.23-1.77), P < 0.0001], and had a lower clinical relapse rate (BoTx 30.2% vs PD 10%, RR 0.32 (0.16-0.65), P = 0.001). Heller myotomy (HM) had superior remission rate compared to PD [HM 94.0% vs PD 64.1%, RR 1.48 (1.15-1.99), P = 0.002]. In uncontrolled trials, the effectiveness of PD was 86.6% (23.9%) vs 94.8% (10.6%) for HM. The main complications of PD were perforation and gastroesophageal reflux disease. CONCLUSION: HM is the most effective long-term treatment for patients with achalasia in China. In the future, controlled clinical trials on the treatment of achalasia should focus on comparing laparoscopic myotomy with or without antireflux procedure,including different partial and total fundoplication techniques. 展开更多
关键词 META-ANALYSIS ACHALASIA ESOPHAGEAL TREATMENT Pneumatic dilation Botulinum toxin injection Laparoscopic myotomy
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Endoscopic ultrasound-guided treatments: Are we getting evidence based- a systematic review 被引量:21
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作者 Carlo Fabbri Carmelo Luigiano +4 位作者 Andrea Lisotti Vincenzo Cennamo Clara Virgilio Giancarlo Caletti Pietro Fusaroli 《World Journal of Gastroenterology》 SCIE CAS 2014年第26期8424-8448,共25页
The continued need to develop less invasive alternatives to surgical and radiologic interventions has driven the development of endoscopic ultrasound(EUS)-guided treatments.These include EUS-guided drainage of pancrea... The continued need to develop less invasive alternatives to surgical and radiologic interventions has driven the development of endoscopic ultrasound(EUS)-guided treatments.These include EUS-guided drainage of pancreatic fluid collections,EUS-guided necrosectomy,EUS-guided cholangiography and biliary drainage,EUSguided pancreatography and pancreatic duct drainage,EUS-guided gallbladder drainage,EUS-guided drainage of abdominal and pelvic fluid collections,EUS-guided celiac plexus block and celiac plexus neurolysis,EUSguided pancreatic cyst ablation,EUS-guided vascular interventions,EUS-guided delivery of antitumoral agents and EUS-guided fiducial placement and brachytherapy.However these procedures are technically challenging and require expertise in both EUS and interventional endoscopy,such as endoscopic retrograde cholangiopancreatography and gastrointestinal stenting.We undertook a systematic review to record the entire body of literature accumulated over the past 2decades on EUS-guided interventions with the objective of performing a critical appraisal of published articles,based on the classification of studies according to levels of evidence,in order to assess the scientific progress made in this field. 展开更多
关键词 Endoscopic ultrasound Pseudocyst drainage NECROSECTOMY Celiac plexus neurolysis Levels of evidence Fine needle injection
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Conceptual Design of Neutral Beam Injection System for EAST 被引量:18
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作者 胡纯栋 NBI Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第6期567-572,共6页
Neutral beam injection (NBI) system with two neutral beam injections will be con- structed on the Experimental Advanced Superconducting Tokamak (EAST) in two stages for high power auxiliary plasmas heating and non... Neutral beam injection (NBI) system with two neutral beam injections will be con- structed on the Experimental Advanced Superconducting Tokamak (EAST) in two stages for high power auxiliary plasmas heating and non-inductive current drive. Each NBI can deliver 2-4 MW beam power with 50-80 keV beam energy in 10-100 s pulse length. Each elements of the NBI system are presented in this contribution. 展开更多
关键词 neutral beam injection system TOKAMAK EAST auxiliary heating
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Hepatitis C virus in Pakistan:A systematic review of prevalence,genotypes and risk factors 被引量:12
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作者 Yasir Waheed Talha Shafi +1 位作者 Sher Zaman Safi Ishtiaq Qadri 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第45期5647-5653,共7页
In Pakistan more than 10 million people are living with Hepatitis C virus (HCV), with high morbidity and mortality. This article reviews the prevalence, genotypes and factors associated with HCV infection in the Pakis... In Pakistan more than 10 million people are living with Hepatitis C virus (HCV), with high morbidity and mortality. This article reviews the prevalence, genotypes and factors associated with HCV infection in the Pakistani population. A literature search was performed by using the keywords; HCV prevalence, genotypes and risk factors in a Pakistani population, in Pubmed, PakMediNet and Google scholar. Ninetyone different studies dating from 1994 to May 2009 were included in this study, and weighted mean and standard error of each population group was calculated. Percentage prevalence of HCV was 4.95% ± 0.53% in the general adult population, 1.72% ± 0.24% in the pediatric population and 3.64% ± 0.31% in a young population applying for recruitment, whereas a very high 57% ± 17.7% prevalence was observed in injecting drug users and 48.67% ± 1.75% in a multi-transfused population. Most prevalent genotype of HCV was 3a. HCV prevalence was moderate in the general population but very high in injecting drug users and multi-transfused populations. This data suggests that the major contributing factors towards increased HCV prevalence include unchecked blood transfusions and reuse of injection syringes. Awareness programs are required to decrease the future burden of HCV in the Pakistani population. 展开更多
关键词 Hepatitis C virus PREVALENCE GENOTYPES Blood transfusions INJECTIONS
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Preparation of Thermosensitive Chitosan Formulations Containing 5-Fluorouracil/Poly-3-hydroxybutyrate Microparticles Used as Injectable Drug Delivery System 被引量:7
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作者 昝佳 朱德权 +3 位作者 谭丰苹 蒋国强 林莹 丁富新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第2期235-241,共7页
The auto-gelling and drug release properties of the thermosensitive chitosan-β-glycerophosphate formulation were investigated. According to rheological study, gelation lag time of chitosan/β-glycerophosphate (GP) ... The auto-gelling and drug release properties of the thermosensitive chitosan-β-glycerophosphate formulation were investigated. According to rheological study, gelation lag time of chitosan/β-glycerophosphate (GP) solutions varied from 2 to 60min with different deacetylation degree of chitosan, pH, gelation temperature, and the particles in the sol. The gelation properties were also found to influence the release profilles of a hydrophilic drug, 5-fluorouracil (5-FU). Morphological examination by scanning electron microphotography demonstrated that large "pores" occurred during the gel-forming process, which created hydrophilic environment and led to the rapid initial release of the drug (85% in f'LrSt 8h). Poly-3-hydroxybutyrate (PHB), a biodegradable material, was applied here as scaffold to capture 5-FU into microparticles with high encapsulation efficiency by solvent-nonsolvent method. Combination of these microparticles into the chitosan-β-GP formulation could drop the rapid initial release from 85% down to 29% in the optimized PHB content (75%, by mass). The release could sustain for about 10 months. Tiffs study provided an understanding of the potential of injectable implant using thermosensitive chitosan-β-GP formulation containing PHB based particles for the water soluble drugs that need the property of long-term delivery. 展开更多
关键词 hydrogel CHITOSAN INJECTABLES MICROPARTICLE drug release
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Simulation study of longitudinal injection scheme for HALS with a higher harmonic cavity system 被引量:4
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作者 Zhen-Biao Sun Lei Shang +3 位作者 Feng-Lei Shang Yun-Gai Tang Wei Liu Wen-Bin Song 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第7期77-82,共6页
Longitudinal injection is a promising on-axis injection scheme for diffraction-limited storage rings. In the latest version of the Hefei advanced light source (HALS), both the dynamic aperture and momentum aperture ha... Longitudinal injection is a promising on-axis injection scheme for diffraction-limited storage rings. In the latest version of the Hefei advanced light source (HALS), both the dynamic aperture and momentum aperture have been optimized. A longitudinal injection scheme was investigated on the HALS using a doublefrequency radio frequency system. To evaluate the injection performance, various errors were considered. A series of tracking simulations were conducted, and the injection efficiency was obtained under different error levels. 展开更多
关键词 Longitudinal INJECTION Hefei advanced LIGHT SOURCE Double-frequency RF system INJECTION efficiency
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Overview of Development Status for EAST-NBI System 被引量:10
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作者 胡纯栋 谢亚红 +8 位作者 谢远来 刘胜 许永建 梁立振 蒋才超 盛鹏 顾玉明 李军 刘智民 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第10期817-825,共9页
The neutral beam injection (NBI) system was developed on the Experimental Ad- vanced Superconducting Tokamak (EAST) for plasma heating and current driving. This paper presents the brief history, design, developmen... The neutral beam injection (NBI) system was developed on the Experimental Ad- vanced Superconducting Tokamak (EAST) for plasma heating and current driving. This paper presents the brief history, design, development, and the main experimental results of the R&D of neutral beam injector on the test bed and on EAST. In particular, it will describe: (1) how the two beamlines with a total beam power of 8 MW were developed; (2) the design of the EAST-NBI system including the high power ion source, main vacuum chamber, inner components, beam diag- nostic system and sub-system; (3) the experimental results of beamline-1 on the summer campaign of EAST in 2014 and, (4) the status of beamline-2 and the future plan of EAST-NBIs. 展开更多
关键词 neutral beam injection EAST tokamak ion source BEAMLINE
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Thermodynamic analysis and simulation for gas baffle entrance collimator of EAST-NBI system based on thermo-fluid coupled method 被引量:5
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作者 Ling Tao Chun-Dong Hu Yuan-Lai Xie 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第1期90-95,共6页
The world's first full Experimental Advanced Superconducting Tokamak(EAST) is designed with the auxiliary heating method of neutral beam injection(NBI)system. Beam collimators are arranged on both sides of the bea... The world's first full Experimental Advanced Superconducting Tokamak(EAST) is designed with the auxiliary heating method of neutral beam injection(NBI)system. Beam collimators are arranged on both sides of the beam channel for absorbing the divergence beam during the beam transmission process in the EAST-NBI system.The gas baffle entrance collimator(GBEC) is a typical high-heat-flux component located at the entrance of gas baffle. An efficient and accurate analysis of its thermodynamic performance is of great significance to explore the working limit and to ensure safe operation of the system under a high-parameter steady-state condition. Based on the thermo-fluid coupled method, thermodynamic analysis and simulation of GBEC is performed to get the working states and corresponding operating limits at different beam extraction conditions. This study provides a theoretical guidance for the next step to achieve long pulse with highpower experimental operation and has an important reference to ensure the safe operation of the system. 展开更多
关键词 Neutral BEAM injection High-heat-flux component BEAM COLLIMATOR Thermo-fluid coupled method Thermodynamic analysis
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The Supervisory Control System for the HL-2A Neutral Beam Injector 被引量:5
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作者 李波 李立 +8 位作者 冯鲲 王雪云 杨家兴 黄治辉 康自华 王明伟 张国庆 雷光玖 饶军 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第3期374-376,共3页
Supervisory control and protection system of the neutral beam injector (NBI) in the HL-2A tokamak is presented. The system is used for a safe coordination of all the main NBI subsystems. Because the system is based ... Supervisory control and protection system of the neutral beam injector (NBI) in the HL-2A tokamak is presented. The system is used for a safe coordination of all the main NBI subsystems. Because the system is based on computer networks with its transmission medium of optical fiber, its advantages in high operational stability, reliability, security and flexible functional expandability are clearly shown during the NBI commissioning and heating experiment in HL-2A. 展开更多
关键词 control timing sequence INTERLOCK PROTECTION ISOLATION neutral beam injection
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Research on DC Protection Strategy in Multi-Terminal Hybrid HVDC System 被引量:7
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作者 Yuping Zheng Jiawei He +3 位作者 Bin Li Tonghua Wua Wei Dai Ye Li 《Engineering》 SCIE EI 2021年第8期1064-1075,共12页
Multi-terminal hybrid high-voltage direct current(HVDC)systems have been developed quickly in recent years in power transmission area.However,for voltage-source converter(VSC)stations in hybrid HVDC systems,no direct ... Multi-terminal hybrid high-voltage direct current(HVDC)systems have been developed quickly in recent years in power transmission area.However,for voltage-source converter(VSC)stations in hybrid HVDC systems,no direct current(DC)filters are required.In addition,the DC reactor is also not installed at the line end because the DC fault can be limited by the converter itself.This means that the boundary element at the line end is absent,and the single-ended protections used in line commutated converter(LCC)based HVDC(LCC-HVDC)systems or VSC-HVDC systems cannot distinguish the fault line in multi-terminal hybrid HVDC systems.This paper proposes a novel singleended DC protection strategy suitable for the multi-terminal hybrid HVDC system,which mainly applies the transient information and active injection concept to detect and distinguish the fault line.Compared with the single-ended protections used in LCC-HVDC and VSC-HVDC systems,the proposed protection strategy is not dependent on the line boundary element and is thus suitable for the multiterminal hybrid HVDC system.The corresponding simulation cases based on power systems computer aided design(PSCAD)/electromagnetic transients including DC(EMTDC)are carried out to verify the superiority of the proposed protection. 展开更多
关键词 Multi-terminal hybrid HVDC system Single-ended protection Transient information Active injection
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Water-Assisted Injection Molding System Based on Water Hydraulic Proportional Control Technique 被引量:5
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作者 ZHOU Hua ZHANG Zengmeng +1 位作者 GAO Yuan'an YANG Huayong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第4期418-427,共10页
Water-assisted injection molding(WAIM), an innovative process to mold plastic parts with hollow sections, is characterized with intermittent, periodic process and large pressure and flow rate variation. Energy savin... Water-assisted injection molding(WAIM), an innovative process to mold plastic parts with hollow sections, is characterized with intermittent, periodic process and large pressure and flow rate variation. Energy savings and injection pressure control can not be .attained based on conventional valve control system. Moreover, the injection water can not be supplied directly by water hydraulic proportional control system. Poor efficiency and control performance are presented by current trial systems, which pressurize injection water by compressed air. In this paper, a novel water hydraulic system is developed applying an accumulator for energy saving. And a new differential pressure control method is proposed by using pressure cylinder and water hydraulic proportional pressure relief valve for back pressure control. Aiming at design of linear controller for injection water pressure regulation, a linear load model is approximately built through computational fluid dynamics(CFD) simulation on two-phase flow cavity filling process with variable temperature and viscosity, and a linear model of pressure control system is built with the load model and linearization of water hydraulic components. According to the simulation, model based feedback is brought forward to compensate the pressure decrease during accumulator discharge and eliminate the derivative element of the system. Meanwhile, the steady-state error can be reduced and the capacity of resisting disturbance can be enhanced, by closed-loop control of load pressure with integral compensation. Through the developed experimental system in the State Key Lab of Fluid Power Transmission and Control, Zhejiang University, China, the static characteristic of the water hydraulic proportional relief valve was tested and output pressure control of the system in Acrylonitrile Butadiene Styrene(ABS) parts molding experiments was also studied. The experiment results show that the dead band and hysteresis of the water hydraulic proportional pressure relief valve are large, but the control precision and linearity can be improved with feed-forward compensation. With the experimental results of injection water pressure control, the applicability of this WAIM system and the effect of its linear controller are verified. The novel proposed process of WAIM pressure control and study on characteristics of control system contribute to the application of water hydraulic proportional control and WAIM technology. 展开更多
关键词 water-assisted injection molding water hydraulics proportional pressure control linear control load characteristic
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