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Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production:Physicochemical characteristics and gasification kinetics analysis
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作者 Han Dang Runsheng Xu +2 位作者 Jianliang Zhang Mingyong Wang Jinhua Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期268-281,共14页
The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile con... The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile content of biochar ranged from 16.19%to 45.35%,and the alkali metal content,ash content,and specific surface area were significantly reduced.The optimal route for biochar pro-duction is hydrothermal carbonization-pyrolysis(P-HC),resulting in biochar with a higher calorific value,C=C structure,and increased graphitization degree.The apparent activation energy(E)of the sample ranges from 199.1 to 324.8 kJ/mol,with P-HC having an E of 277.8 kJ/mol,lower than that of raw biomass,primary biochar,and anthracite.This makes P-HC more suitable for blast furnace injection fuel.Additionally,the paper proposes a path for P-HC injection in blast furnaces and calculates potential environmental benefits.P-HC of-fers the highest potential for carbon emission reduction,capable of reducing emissions by 96.04 kg/t when replacing 40wt%coal injec-tion. 展开更多
关键词 blast furnace injection BIOMASS cross-upgrading hydrothermal carbonization PYROLYSIS physicochemical properties gasific-ation properties
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Shenqi Fuzheng injection alleviates chemotherapy-induced cachexia by restoring glucocorticoid signaling in hypothalamus
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作者 Entezar Berik Zijia Zhang +16 位作者 Wei Li Yawen Liu Sihan Chen Wenyong Wu Zhaojun Wang Xinqin Kong Wenqiang Pei Huiqing Dong Huali Long Min Lei Jennifer Yiyang Wang Liangfeng Liu Jinjun Hou Jing Feng Zhaoxia Li Wanying Wu De-an Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第3期431-434,共4页
Chemotherapy-induced cachexia(CIC)is a debilitating condition characterized by weight loss,muscle atrophy,and anorexia[1].While peripheral mechanisms of cachexia have been extensively studied,the involvement of the ce... Chemotherapy-induced cachexia(CIC)is a debilitating condition characterized by weight loss,muscle atrophy,and anorexia[1].While peripheral mechanisms of cachexia have been extensively studied,the involvement of the central nervous system(CNS)in CIC is often overlooked.Chemotherapeutic drugs cause stress responses and inflammation,which may impact the hypothalamus and disrupt systemic energy and neuroendocrine functions.Understanding hypothalamic roles in regulating these processes can provide insights into CIC's mechanisms and aid in developing novel therapies. 展开更多
关键词 injection DRUGS GLUCOCORTICOID CHEMOTHERAPY
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Wetting front migration model of ion-adsorption rare earth during the multi-hole unsaturated liquid injection
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作者 Yu Wang Xiaojun Wang +8 位作者 Yuchen Qiu Hao Wang Gang Li Kaijian Hu Wen Zhong Zhongqun Guo Bing Li Chunlei Zhang Guangxiang Ye 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期483-496,共14页
In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distanc... In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distance of wetting fronts are still unclear.Besides,wetting front migration distance and leaching time are usually required to optimize the leaching process.In this study,wetting front migration tests of ionadsorption rare earth ores during the multi-hole fluid injection(the spacing between injection holes was 10 cm,12 cm and 14 cm)and single-hole fluid injection were completed under the constant water head height.At the pre-intersection stage,the wetting front migration laws of ion-adsorption rare earth ores during the multi-hole fluid injection and single-hole fluid injection were identical.At the postintersection stage,the intersection accelerated the wetting front migration.By using the Darcy’s law,the intersection effect of wetting fronts during the multi-hole liquid injection was transformed into the water head height directly above the intersection.Finally,based on the Green-Ampt model,a wetting front migration model of ion-adsorption rare earth ores during the multi-hole unsaturated liquid injection was established.Error analysis results showed that the proposed model can accurately simulate the infiltration process under experimental conditions.The research results enrich the infiltration law and theory of ion-adsorption rare earth ores during the multi-hole liquid injection,and this study provides a scientific basis for optimizing the liquid injection well pattern parameters of ion-adsorption rare earth in situ leaching in the future. 展开更多
关键词 Ion-adsorption rare earth ore Multi-hole unsaturated liquid injection In situ leaching Intersection effect Calculation model
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Tofacitinib combined with local low-dose ixekizumab injection benefits those with peripheral psoriatic arthritis
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作者 Yours Sincerely Ruiyuan Xia +2 位作者 Weixin Zhang Jing Hang Zhiqiang Yin 《The Journal of Biomedical Research》 CAS CSCD 2024年第1期92-94,共3页
Dear Editor,Treating psoriatic arthritis(PsA)is always difficult.Systemic treatments can be administered either orally or through intramuscular and intra-articular injection,including conventional synthetics,biologics... Dear Editor,Treating psoriatic arthritis(PsA)is always difficult.Systemic treatments can be administered either orally or through intramuscular and intra-articular injection,including conventional synthetics,biologics and targeted synthetic disease-modifying antirheumatic drugs[1].The alternatives,topical external therapies,are not effective on joint lesions due to drug permeability issues.Drugs injected into the articular cavity are also unsuitable for small peripheral joint lesions,the most common manifestations of PsA.The limited treatment options for PsA present a challenge. 展开更多
关键词 injection DRUGS cavity treatment
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Does HSP27 injection induce glaucoma damage in mice?
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作者 Stephanie C.Joachim Sabrina Reinehr 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2347-2348,共2页
In a further aging society,excellent eyesight is an integral part of overall well-being and quality of life.Preserving good vision is crucial to maintaining mobility,independence,and mental health.There can be several... In a further aging society,excellent eyesight is an integral part of overall well-being and quality of life.Preserving good vision is crucial to maintaining mobility,independence,and mental health.There can be several reasons for visual impairment in elderly people,these include age-related macular degeneration,the leading cause of vision loss among older adults,cataract,glaucoma,diabetic retinopathy,retinal detachment,and others. 展开更多
关键词 HSP27 injection DAMAGE
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Numerical Simulation of Asphaltene Precipitation and Deposition during Natural Gas and CO_(2) Injection
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作者 Shasha Feng Yi Liao +3 位作者 Weixin Liu Jianwen Dai Mingying Xie Li Li 《Fluid Dynamics & Materials Processing》 EI 2024年第2期275-292,共18页
Asphaltene deposition is a significant problem during gas injection processes,as it can block the porous medium,the wellbore,and the involved facilities,significantly impacting reservoir productivity and ultimate oil re... Asphaltene deposition is a significant problem during gas injection processes,as it can block the porous medium,the wellbore,and the involved facilities,significantly impacting reservoir productivity and ultimate oil recovery.Only a few studies have investigated the numerical modeling of this potential effect in porous media.This study focuses on asphaltene deposition due to natural gas and CO_(2) injection.Predictions of the effect of gas injection on asphaltene deposition behavior have been made using a 3D numerical simulation model.The results indicate that the injection of natural gas exacerbates asphaltene deposition,leading to a significant reduction in permeability near the injection well and throughout the reservoir.This reduction in permeability strongly affects the ability of gas toflow through the reservoir,resulting in an improvement of the displacement front.The displacement effi-ciency of the injection gas process increases by up to 1.40%when gas is injected at 5500 psi,compared to the scenario where the asphaltene model is not considered.CO_(2) injection leads to a miscible process with crude oil,extracting light and intermediate components,which intensifies asphaltene precipitation and increases the viscosity of the remaining crude oil,ultimately reducing the recovery rate. 展开更多
关键词 Reservoir simulation asphaltenes deposition natural gas injection CO_(2)injection
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Background diseases and the number of previous intravitreal aflibercept injections on immediate intraocular pressure increase and vitreous reflux rate in phakic eyes
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作者 Tetsuya Muto Shigeki Machida Shinichiro Imaizumi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期545-550,共6页
●AIM:To evaluate the effect of background diseases and number of previous intravitreal aflibercept injections(IVAIs)on immediate intraocular pressure(IOP)increase and vitreous reflux(VR)rate and to evaluate the corre... ●AIM:To evaluate the effect of background diseases and number of previous intravitreal aflibercept injections(IVAIs)on immediate intraocular pressure(IOP)increase and vitreous reflux(VR)rate and to evaluate the correlation of both age and axial length with immediate IOP increase and VR rate.●METHODS:This study included 105 patients with cystoid macular edema secondary to retinal vein occlusion,35 patients with diabetic macular edema,69 patients with neovascular age-related macular degeneration(nAMD),and 12 patients with myopic choroidal neovascularization,which underwent first-time IVAI.The correlation of immediate IOP increase and VR rates with the four background diseases was investigated.Moreover,the correlation of age with immediate IOP increase and VR rate as well as correlation of axial length with immediate IOP increase and VR rate were evaluated.Further,54 patients with nAMD were treated with IVAI>10 times(multiple IVAIs).Moreover,the correlation of immediate IOP increase and VR rates with first-time and multiple IVAIs in nAMD was determined.●RESULTS:The immediate IOP increase(P=0.16)and VR rates(P=0.50)were almost similar among the four background diseases.The immediate postinjection IOP and age,VR rate and age,immediate postinjection IOP and axial length,or VR rate and axial length were not correlated in the four background diseases.The immediate IOP increase(P=0.66)and VR rates(P=0.28)did not significantly differ between first-time and multiple IVAIs in nAMD.●CONCLUSION:Background diseases and number of previous IVAIs have no effect on immediate IOP increase and VR rate.Further,age and axial length have no correlation on immediate IOP increase and VR rate. 展开更多
关键词 AFLIBERCEPT intraocular pressure vitreous reflux intravitreal injection
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A New Heat Transfer Model for Multi-Gradient Drilling with Hollow Sphere Injection
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作者 Jiangshuai Wang Chuchu Cai +3 位作者 Pan Fu Jun Li Hongwei Yang Song Deng 《Fluid Dynamics & Materials Processing》 EI 2024年第3期537-546,共10页
Multi-gradient drilling is a new offshore drilling method.The accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise cont... Multi-gradient drilling is a new offshore drilling method.The accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise control of the wellbore pressure.In this study,a new heat transfer model is proposed by which the variable mass flow is properly taken into account.Using this model,the effects of the main factors influencing the wellbore temperature are analyzed.The results indicate that at the position where the separation injection device is installed,the temperature increase of the fluid in the drill pipe is mitigated due to the inflow/outflow of hollow spheres,and the temperature drop of the fluid in the annulus also decreases.In addition,a lower separation efficiency of the device,a shallower installation depth and a smaller circulating displacement tend to increase the temperature near the bottom of the annulus,thereby helping to reduce the hydrate generation area and playing a positive role in the prevention and control of hydrates in deepwater drilling. 展开更多
关键词 Multi-gradient drilling wellbore temperature HYDRATE separate injection device variable mass
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Endoscopic band ligation or endoscopic tissue adhesive injection in the treatment of gastric varices:Which is better?
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作者 Li-Zhi Yi Sheng-Bing Zhao 《World Journal of Gastroenterology》 SCIE CAS 2024年第21期2827-2828,共2页
The combination of endoscopic ultrasound with endoscopic treatment of type 1 gastric variceal hemorrhage may improve the robustness and generalizability of the findings in future studies.Moreover,the esophageal varice... The combination of endoscopic ultrasound with endoscopic treatment of type 1 gastric variceal hemorrhage may improve the robustness and generalizability of the findings in future studies.Moreover,the esophageal varices should also be included in the evaluation of treatment efficacy in subsequent studies to reach a more convincing conclusion. 展开更多
关键词 Gastric varices Esophageal varices Endoscopic band ligation Endoscopic tissue adhesive injection Endoscopic ultrasound
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Permanent Magnet Temperature Estimation for PMSMs Using Virtual Position-offset Injection
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作者 Beichen Ding Yuting Lu +2 位作者 Kaide Huang Guodong Feng Chunyan Lai 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期51-60,共10页
This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is math... This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is mathematically transforming the machine model to a virtual frame with a position-offset. The virtual frame temperature estimation model is derived to calculate the permanent magnet temperature(PMT) directly from the measurements with computation efficiency. The estimation model involves a combined inductance term, which can simplify the establishment of saturation compensation model with less measurements. Moreover, resistance and inverter distorted terms are cancelled in the estimation model, which can improve the robustness to the winding temperature rise and inverter distortion. The proposed approach can achieve simplified computation in temperature estimation and reduced memory usage in saturation compensation. While existing model-based approaches could be affected by either the need of resistance and inverter information or complex saturation compensation. Experiments are conducted on the test machine to verify the proposed approach under various operating conditions. 展开更多
关键词 PMSM Magnet temperature estimation Virtual position offset injection Inverter nonlinearity
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Transparent cap adjusted the stent placed for stenosis after endoscopic injection of esophageal varices:A case report
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作者 Fu-Long Zhang Jing Xu +8 位作者 Yuan-Dong Zhu Qian-Neng Wu Yan Shi Lei Fang Dan Zhou Hai Wang Chao-JunHuang Chun-Hua Zhou Qun Zhu 《World Journal of Clinical Cases》 SCIE 2024年第15期2614-2620,共7页
BACKGROUND The stent embedded in the esophageal mucosa is one of the complications after stenting for esophageal stricture.We present a case of stent adjustment with the aid of a transparent cap after endoscopic injec... BACKGROUND The stent embedded in the esophageal mucosa is one of the complications after stenting for esophageal stricture.We present a case of stent adjustment with the aid of a transparent cap after endoscopic injection of an esophageal varices stent.CASE SUMMARY A 61-year-old male patient came to the hospital with discomfort of the chest after the stent implanted for the stenosis because of endoscopic injection of esophageal varices.The gastroscopy was performed,and the stent embedded into the esophageal mucosa.At first,we pulled the recycling line for shrinking the stent,however,the mucosa could not be removed from the stent.Then a forceps was performed to remove the mucosa in the stent,nevertheless,the bleeding form the mucosa was obvious.And then,we used a transparent cap to scrape the mucosa along the stent,and the mucosa were removed successfully without bleeding.CONCLUSION A transparent cap helps gastroscopy to remove the mucosa embedded in the stent after endoscopic injection of the esophageal varices stent. 展开更多
关键词 STENT Transparent cap STENOSIS Endoscopic injection Esophageal varices Case report
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Endoscopic ultrasound-guided lauromacrogol injection for treatment of colorectal cavernous hemangioma:Two case reports
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作者 Hua-Tuo Zhu Wen-Guo Chen +4 位作者 Jing-Jie Wang Jia-Nan Guo Fen-Ming Zhang Guo-Qiang Xu Hong-Tan Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期966-973,共8页
BACKGROUND Colorectal cavernous hemangioma is a rare vascular malformation resulting in recurrent lower gastrointestinal hemorrhage,and can be misinterpreted as colitis.Surgical resection is currently the mainstay of ... BACKGROUND Colorectal cavernous hemangioma is a rare vascular malformation resulting in recurrent lower gastrointestinal hemorrhage,and can be misinterpreted as colitis.Surgical resection is currently the mainstay of treatment,with an emphasis on sphincter preservation.CASE SUMMARY We present details of two young patients with a history of persistent hematochezia diagnosed with colorectal cavernous hemangioma by endoscopic ultrasound(EUS).Cavernous hemangioma was relieved by several EUS-guided lauromacrogol injections and the patients achieved favorable clinical prognosis.CONCLUSION Multiple sequential EUS-guided injections of lauromacrogol is a safe,effective,cost-efficient,and minimally invasive alternative for colorectal cavernous hemangioma. 展开更多
关键词 Endoscopic ultrasound Lauromacrogol injection Colorectal cavernous hemangioma Case report
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GUARDIAN: A Multi-Tiered Defense Architecture for Thwarting Prompt Injection Attacks on LLMs
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作者 Parijat Rai Saumil Sood +1 位作者 Vijay K. Madisetti Arshdeep Bahga 《Journal of Software Engineering and Applications》 2024年第1期43-68,共26页
This paper introduces a novel multi-tiered defense architecture to protect language models from adversarial prompt attacks. We construct adversarial prompts using strategies like role emulation and manipulative assist... This paper introduces a novel multi-tiered defense architecture to protect language models from adversarial prompt attacks. We construct adversarial prompts using strategies like role emulation and manipulative assistance to simulate real threats. We introduce a comprehensive, multi-tiered defense framework named GUARDIAN (Guardrails for Upholding Ethics in Language Models) comprising a system prompt filter, pre-processing filter leveraging a toxic classifier and ethical prompt generator, and pre-display filter using the model itself for output screening. Extensive testing on Meta’s Llama-2 model demonstrates the capability to block 100% of attack prompts. The approach also auto-suggests safer prompt alternatives, thereby bolstering language model security. Quantitatively evaluated defense layers and an ethical substitution mechanism represent key innovations to counter sophisticated attacks. The integrated methodology not only fortifies smaller LLMs against emerging cyber threats but also guides the broader application of LLMs in a secure and ethical manner. 展开更多
关键词 Large Language Models (LLMs) Adversarial Attack Prompt injection Filter Defense Artificial Intelligence Machine Learning CYBERSECURITY
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Residual-Based False Data Injection Attacks Against Multi-Sensor Estimation Systems 被引量:4
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作者 Haibin Guo Jian Sun Zhong-Hua Pang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1181-1191,共11页
This paper investigates the security issue of multisensor remote estimation systems.An optimal stealthy false data injection(FDI)attack scheme based on historical and current residuals,which only tampers with the meas... This paper investigates the security issue of multisensor remote estimation systems.An optimal stealthy false data injection(FDI)attack scheme based on historical and current residuals,which only tampers with the measurement residuals of partial sensors due to limited attack resources,is proposed to maximally degrade system estimation performance.The attack stealthiness condition is given,and then the estimation error covariance in compromised state is derived to quantify the system performance under attack.The optimal attack strategy is obtained by solving several convex optimization problems which maximize the trace of the compromised estimation error covariance subject to the stealthiness condition.Moreover,due to the constraint of attack resources,the selection principle of the attacked sensor is provided to determine which sensor is attacked so as to hold the most impact on system performance.Finally,simulation results are presented to verify the theoretical analysis. 展开更多
关键词 Cyber-physical systems(CPSs) false data injection(FDI)attacks remote state estimation stealthy attacks
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PhaseⅠstudy of chlorogenic acid injection for recurrent high-grade glioma with long-term follow-up 被引量:2
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作者 Zhuang Kang Shan Li +6 位作者 Xun Kang Jing Deng Huarong Yang Feng Chen Jiandong Jiang Jie Zhang Wenbin Li 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第6期465-476,共12页
Objective:This study was aimed at analyzing the efficacy and safety of an injectable form of chlorogenic acid(CGA)in patients with recurrent high-grade glioma after standard of care treatments,through a first-in-human... Objective:This study was aimed at analyzing the efficacy and safety of an injectable form of chlorogenic acid(CGA)in patients with recurrent high-grade glioma after standard of care treatments,through a first-in-human,open-label,dose-escalation phase I trial.Methods:A total of 26 eligible patients were enrolled,received intramuscular CGA injections at 5 dose levels,and were followed up for 5 years.CGA was well tolerated,and the maximum tolerated dose was 5.5 mg/kg.Results:The most common treatment-related adverse events occurred at the sites of injection.No grade 3 or 4 adverse events(e.g.,drug allergy)were reported for these patients except for induration at the injection sites.A clinical pharmacokinetic study showed that CGA was rapidly eliminated from the plasma,with a t_(1/2)of 0.95–1.27 h on day 1 and 1.19–1.39 h on day 30,and no detectable CGA was observed on days 9,11,13,23,25,27,and 29 before CGA administration.After the first treatment cycle,52.2%of patients(12 of 23)achieved stable disease.Long-term follow-up indicated an estimated median overall survival of 11.3 months for all 23 evaluable patients.Of the 18 patients with grade 3 glioma,the median overall survival was 9.5 months.Two patients remained alive at the cutoff day.Conclusions:This phase I study demonstrated that CGA has a favorable safety profile(with no severe toxicity),and provides preliminary clinical benefits for patients with high grade glioma relapsing after prior standard therapies,thus shedding light on the potential clinical application of CGA for recurrent grade 4 glioma. 展开更多
关键词 injection GLIOMA TREATMENT
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Kinematic Control of Serial Manipulators Under False Data Injection Attack 被引量:1
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作者 Yinyan Zhang Shuai Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第4期1009-1019,共11页
With advanced communication technologies,cyberphysical systems such as networked industrial control systems can be monitored and controlled by a remote control center via communication networks.While lots of benefits ... With advanced communication technologies,cyberphysical systems such as networked industrial control systems can be monitored and controlled by a remote control center via communication networks.While lots of benefits can be achieved with such a configuration,it also brings the concern of cyber attacks to the industrial control systems,such as networked manipulators that are widely adopted in industrial automation.For such systems,a false data injection attack on a control-center-to-manipulator(CC-M)communication channel is undesirable,and has negative effects on the manufacture quality.In this paper,we propose a resilient remote kinematic control method for serial manipulators undergoing a false data injection attack by leveraging the kinematic model.Theoretical analysis shows that the proposed method can guarantee asymptotic convergence of the regulation error to zero in the presence of a type of false data injection attack.The efficacy of the proposed method is validated via simulations. 展开更多
关键词 Cyber-physical systems false data injection attack MANIPULATORS remote kinematic control
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Novel gene therapy for rheumatoid arthritis with single local injection: adeno-associated virus-mediated delivery of A_(20)/TNFAIP_(3) 被引量:1
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作者 Qin Zhang Fang-Xing Yu +6 位作者 Yang-Lin Wu Cheng-Yuan Yang Nai-Cheng Liu Xu Zhu Pi-Ming Zhao Zhong-Ya Wang Jun Lin 《Military Medical Research》 SCIE CAS CSCD 2023年第3期418-420,共3页
Dear Editor,Multiple experiments have established TNF-α-induced protein 3 (A20/TNFAIP3) as a critical regulator associated with rheumatoid arthritis(RA)[1,2].The lack of TNF-α-induced protein 3 (A20) promotes the NO... Dear Editor,Multiple experiments have established TNF-α-induced protein 3 (A20/TNFAIP3) as a critical regulator associated with rheumatoid arthritis(RA)[1,2].The lack of TNF-α-induced protein 3 (A20) promotes the NOD-like receptor protein 3 (NLRP3) inflammasome and induces spontaneous arthritis,while increase of A20 reduces the secretion of IL-1β and favors immunological tolerance[3,4]. Hence, we investigate the feasibility of recombinant adeno-associated virus 6 (rAAV6)-mediated A20 gene therapy in a collageninduced arthritis (CIA) model. 展开更多
关键词 NLRP3 injection A_(20)
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Analysis of influencing factors of excitation parameters for magnetoacoustic tomography with current injection 被引量:1
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作者 李粟 刘国强 +3 位作者 郭亮 张文伟 卢朝森 夏慧 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期496-503,共8页
Magneto-acoustic tomography with current injection(MAT-CI) is a type of hybrid imaging;under the excitation of the static magnetic field, the thermoacoustic effect and the Lorentz force effect will exist at the same t... Magneto-acoustic tomography with current injection(MAT-CI) is a type of hybrid imaging;under the excitation of the static magnetic field, the thermoacoustic effect and the Lorentz force effect will exist at the same time. Therefore,the detected signal is a mixed signal generated by the simultaneous action of the two effects, but the influence of excitation parameters on the two effects is different. In this paper, for objects with different conductivity, the proportion of thermoacoustic signal(TA) and magneto-acoustic signal(MA) in the mixed signal is quantitatively analyzed in terms of three aspects: the magnetic induction intensity, pulse excitation and injection current polarity. Experimental and simulation analyses show that the intensity ratio of MA to TA is not affected when the conductivity varies from 0.1 S/m to 1.5 S/m and other conditions remain unchanged. When the amplitude of the pulse excitation and the strength of the magnetic induction are different, the growth rates of MA and TA are different, which has a significant impact on the proportion of the two signals in the mixed signal. At the same time, due to the Lorentz force effect, MA is affected by the polarity of the injected current and the direction of the static magnetic field. The combination of the static magnetic field and the injected current can not only distinguish the two signals in the mixed signal, but also effectively enhance the intensity of the mixed signal and improve the quality of the reconstructed image. 展开更多
关键词 magneto-acoustic tomography with current injection(MAT-CI) thermoacoustic effect Lorentz force effect acoustic source
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Control of electron beam current,charge,and energy spread using density downramp injection in laser wakefield accelerators 被引量:1
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作者 Céline S.Hue Yang Wan +1 位作者 Eitan Y.Levine Victor Malka 《Matter and Radiation at Extremes》 SCIE EI CAS CSCD 2023年第2期14-24,共11页
Density downramp injection has been demonstrated to be an elegant and efficient approach for generating high-quality electron beams in laser wakefield accelerators.Recent studies have demonstrated the possibilities of... Density downramp injection has been demonstrated to be an elegant and efficient approach for generating high-quality electron beams in laser wakefield accelerators.Recent studies have demonstrated the possibilities of generating electron beams with charges ranging from tens to hundreds of picocoulombs while maintaining good beam quality.However,the plasma and laser parameters in these studies have been limited to specific ranges or attention has been focused on separate physical processes such as beam loading,which affects the uniformity of the accelerating field and thus the energy spread of the trapped electrons,the repulsive force from the rear spike of the bubble,which reduces the transverse momentum P⊥of the trapped electrons and results in small beam emittance,and the laser evolution when traveling in the plasma.In this work,we present a comprehensive numerical study of downramp injection in the laser wakefield,and we demonstrate that the current profile of the injected electron beam is directly correlated with the density transition parameters,which further affects the beam charge and energy evolution.By fine-tuning the plasma density parameters,electron beams with high charge(up to several hundreds of picocoulombs)and low energy spread(around 1%FWHM)can be obtained.All these results are supported by large-scale quasi-threedimensional particle-in-cell simulations.We anticipate that the electron beams with tunable beam properties generated using this approach will be suitable for a wide range of applications. 展开更多
关键词 tuning BEAM injection
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Development and prospect of downhole monitoring and data transmission technology for separated zone water injection 被引量:1
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作者 LIU He ZHENG Lichen +4 位作者 YU Jiaqing MING Eryang YANG Qinghai JIA Deli CAO Gang 《Petroleum Exploration and Development》 2023年第1期191-201,共11页
This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptabi... This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in detail.Problems and challenges of existing technologies in downhole monitoring and data transmission technology are pointed out.According to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is proposed.For the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole plug.For the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and reliable.For large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and adjustment.In line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development. 展开更多
关键词 separated zone water injection downhole monitoring data transmission cable communication vibration wave pressure wave flow wave
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