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Current optimization-based control of dual three-phase PMSM for low-frequency temperature swing reduction
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作者 Linlin Lu Xueqing Wang +3 位作者 Luhan Jin Qiong Liu Yun Zhang Yao Mao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期238-246,共9页
In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature swing.The reduction of temperatur... In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature swing.The reduction of temperature swing can be equivalent to reducing maximum instantaneous phase copper loss in this paper.First,a two-level optimization aiming at minimizing maximum instantaneous phase copper loss at each electrical angle is proposed.Then,the optimization is transformed to a singlelevel optimization by introducing the auxiliary variable for easy solving.Considering that singleobjective optimization trades a great total copper loss for a small reduction of maximum phase copper loss,the optimization considering both instantaneous total copper loss and maximum phase copper loss is proposed,which has the same performance of temperature swing reduction but with lower total loss.In this way,the proposed control scheme can reduce maximum junction temperature by 11%.Both simulation and experimental results are presented to prove the effectiveness and superiority of the proposed control scheme for low-frequency temperature swing reduction. 展开更多
关键词 Dual three-phase PMSM Low-frequency temperature swing Copper loss Current optimization Connected neutral points
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Deciphering engineering principle of three-phase interface for advanced gas-involved electrochemical reactions 被引量:2
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作者 Yanzheng He Sisi Liu +3 位作者 Mengfan Wang Qiyang Cheng Tao Qian Chenglin Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期302-323,I0008,共23页
As an alternative to conventional energy conversion and storage reactions,gas-involved electrochemical reactions,including the carbon dioxide reduction reaction(CO_(2)RR),nitrogen reduction reaction(NRR)and hydrogen e... As an alternative to conventional energy conversion and storage reactions,gas-involved electrochemical reactions,including the carbon dioxide reduction reaction(CO_(2)RR),nitrogen reduction reaction(NRR)and hydrogen evolution reaction(HER),have become an emerging research direction and have gained increasing attention due to their advantages of environmental friendliness and sustainability.Various studies have been designed to accelerate sluggish kinetics but with limited results.Most of them promote the reaction by modulating the intrinsic properties of the catalyst,ignoring the synergistic effect of the reaction as a whole.Due to the introduction of gas,traditional liquid-solid two-phase reactions are no longer applicable to future research.Since gas-involved electrochemical reactions mostly occur at the junctions of gaseous reactants,liquid electrolytes and solid catalysts,the focus of future research on reaction kinetics should gradually shift to three-phase reaction interfaces.In this review,we briefly introduce the formation and constraints of the three-phase interface and propose three criteria to judge its merit,namely,the active site,mass diffusion and electron mass transfer.Subsequently,a series of modulation methods and relevant works are discussed in detail from the three improvement directions of‘exposing more active sites,promoting mass diffusion and accelerating electron transfer’.Definitively,we provide farsighted insights into the understanding and research of three-phase interfaces in the future and point out the possible development direction of future regulatory methods,hoping that this review can broaden the future applications of the three-phase interface,including but not limited to gas-involved electrochemical reactions. 展开更多
关键词 three-phase reaction Surface reactions Mass diffusion Electron transfer Gas-involved electrochemical reactions
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Electrical characteristics of new three-phase traction power supply system for rail transit 被引量:1
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作者 Xiaohong Huang Hanlin Wang +4 位作者 Qunzhan Li Naiqi Yang Tao Ren You Peng Haoyang Li 《Railway Engineering Science》 2023年第1期75-88,共14页
A novel three-phase traction power supply system is proposed to eliminate the adverse effects caused by electric phase separation in catenary and accomplish a unifying manner of traction power supply for rail transit.... A novel three-phase traction power supply system is proposed to eliminate the adverse effects caused by electric phase separation in catenary and accomplish a unifying manner of traction power supply for rail transit.With the application of two-stage three-phase continuous power supply structure,the electrical characteristics exhibit new features differing from the existing traction system.In this work,the principle for voltage levels determining two-stage network is dissected in accordance with the requirements of traction network and electric locomotive.The equivalent model of three-phase traction system is built for deducing the formula of current distribution and voltage losses.Based on the chain network model of the traction network,a simulation model is established to analyze the electrical characteristics such as traction current distribution,voltage losses,system equivalent impedance,voltage distribution,voltage unbalance and regenerative energy utilization.In a few words,quite a lot traction current of about 99%is undertaken by long-section cable network.The proportion of system voltage losses is small attributed to the two-stage three-phase power supply structure,and the voltage unbal-ance caused by impedance asymmetry of traction network is less than 1‰.In addition,the utilization rate of regenerative energy for locomotive achieves a significant promotion of over 97%. 展开更多
关键词 three-phase AC power supply Two-stage power supply structure Electrical characteristics Current distribution Voltage losses Regenerative energy
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Speed Regulation Method Using Genetic Algorithm for Dual Three-phase Permanent Magnet Synchronous Motors 被引量:1
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作者 Xiuhong Jiang Yuying Wang Jiarui Dong 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第2期171-178,共8页
Dual three-phase Permanent Magnet Synchronous Motor(DTP-PMSM)is a nonlinear,strongly coupled,high-order multivariable system.In today’s application scenarios,it is difficult for traditional PI controllers to meet the... Dual three-phase Permanent Magnet Synchronous Motor(DTP-PMSM)is a nonlinear,strongly coupled,high-order multivariable system.In today’s application scenarios,it is difficult for traditional PI controllers to meet the requirements of fast response,high accuracy and good robustness.In order to improve the performance of DTP-PMSM speed regulation system,a control strategy of PI controller based on genetic algorithm is proposed.Firstly,the basic mathematical model of DTP-PMSM is established,and the PI parameters of DTP-PMSM speed regulation system are optimized by genetic algorithm,and the modeling and simulation experiments of DTP-PMSM control system are carried out by MATLAB/SIMULINK.The simulation results show that,compared with the traditional PI control,the proposed algorithm significantly improves the performance of the control system,and the speed output overshoot of the GA-PI speed control system is smaller.The anti-interference ability is stronger,and the torque and double three-phase current output fluctuations are smaller. 展开更多
关键词 Dual three-phase permanent magnet synchronous motor Genetic algorithm PI control Speed regulation
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Complication rates after direct anterior vs posterior approach for hip hemiarthroplasty in elderly individuals with femoral neck fractures 被引量:3
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作者 Tatiana Charles Nicolas Bloemers +1 位作者 Bilal Kapanci Marc Jayankura 《World Journal of Orthopedics》 2024年第1期22-29,共8页
BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with ... BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with no consensus regarding the superiority of any single approach.AIM To compare early postoperative complications after implementing the direct anterior and posterior approaches(PL)for hip hemiarthroplasty after femoral neck fractures.METHODS This is a comparative,retrospective,single-center cohort study conducted at a university hospital.Between March 2008 and December 2018,273 patients(a total of 280 hips)underwent bipolar hemiarthroplasties(n=280)for displaced femoral neck fractures using either the PL(n=171)or the minimally invasive direct anterior approach(DAA)(n=109).The choice of approach was related to the surgeons’practices;the implant types were similar and unrelated to the approach.Dislocation rates and other complications were reviewed after a minimum followup of 6 mo.RESULTS Both treatment groups had similarly aged patients(mean age:82 years),sex ratios,patient body mass indexes,and patient comorbidities.Surgical data(surgery delay time,operative time,and blood loss volume)did not differ significantly between the groups.The 30 d mortality rate was higher in the PL group(9.9%)than in the DAA group(3.7%),but the difference was not statistically significant(P=0.052).Among the one-month survivors,a significantly higher rate of dislocation was observed in the PL group(14/154;9.1%)than in the DAA group(0/105;0%)(P=0.002).Of the 14 patients with dislocation,8 underwent revision surgery for recurrent instability(posterior group),and one of them had 2 additional procedures due to a deep infection.The rate of other complications(e.g.,perioperative and early postoperative periprosthetic fractures and infection-related complications)did not differ significantly between the groups.CONCLUSION These findings suggest that the DAA to bipolar hemiarthroplasty for patients with femoral neck fractures is associated with a lower dislocation rate(<1%)than the PL. 展开更多
关键词 HEMIARTHROPLASTY Femoral neck fracture Direct anterior approach Posterior approach DISLOCATION MORTALITY
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Optimization of Control Loops and Operating Parameters for Three-Phase Separators Used in Oilfield Central Processing Facilities
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作者 Zhenfeng Li Yaqiao Li Guangjun Wei 《Fluid Dynamics & Materials Processing》 EI 2023年第3期635-649,共15页
In this study,the Stokes formula is used to analyze the separation effect of three-phase separators used in a Oilfield Central Processing Facility.The considered main influencing factors include(but are not limited to... In this study,the Stokes formula is used to analyze the separation effect of three-phase separators used in a Oilfield Central Processing Facility.The considered main influencing factors include(but are not limited to)the typical size of oil and water droplets,the residence time and temperature of fluid and the dosage of demulsifier.Using the“Specification for Oil and Gas Separators”as a basis,the control loops and operating parameters of each separator are optimized Considering the Halfaya Oilfield as a testbed,it is shown that the proposed approach can lead to good results in the production stage. 展开更多
关键词 Distributed control system(DCS) three-phase separator control loop operating parameter
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Purification of Moringa oleifera Leaves Protease by Three-Phase Partitioning and Investigation of Its Potential Antibacterial Activity
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作者 Adam Abdoulaye Agossou D. P. Noumavo +6 位作者 Durand Dah-Nouvlessounon Messan A. B. Ohin Hasan Bayraktar Farid T. Bade Honoré S. Bankole Lamine Baba-Moussa Farid Baba-Moussa 《American Journal of Plant Sciences》 CAS 2023年第1期64-76,共13页
One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for thei... One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for their purifications. As such, three-phase partitioning (TPP) was used to purify protease from moringa (Moringa oleifera). TPP is an emerging, promising, non-chromatographic and economical technology which is simple, quick, efficient and often one-step process for the separation and purification of bioactive molecules from natural sources. It involves the addition of salt (ammonium sulphate) to the crude extract followed by the addition of an organic solvent (butanol). The protein appears as an interfacial precipitate between upper organic solvent and lower aqueous phases. The various conditions such as ammonium sulphate, ratio of crude extract to t-butanol and pH which are required for attaining efficient purification of the protease fractions were optimized. Under optimized conditions, it was seen that, 35% of ammonium sulphate saturation with 1:0.75 ratio of crude extract to t-butanol at pH 7 gave 4.94-fold purification with 96.20% activity yield of protease in the middle phase of the TPP system. The purified enzyme from Moringa oleifera has no antimicrobial effect on the pathogenic bacteria tested. However, this purified enzyme, can be considered as a promising agent, cheap, and safe source which is suitable for using in various industries. 展开更多
关键词 three-phase Partitioning Moringa oleifera PROTEASE Protein Purification ANTIMICROBIAL
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Vibration characteristics of sandwich plates with an auxetic honeycomb core and laminated three-phase skin layers under blast load
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作者 Quoc-Hoa Pham Van Ke Tran Trung Thanh Tran 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期148-163,共16页
In this article,vibration characteristics of sandwich plates with an auxetic honeycomb core and laminated three-phase skin layers subjected to blast load are studied.Higher-order ES-MITC3 element based on higher-order... In this article,vibration characteristics of sandwich plates with an auxetic honeycomb core and laminated three-phase skin layers subjected to blast load are studied.Higher-order ES-MITC3 element based on higher-order shear deformation theory(HSDT)to achieve the governing equations.The sandwich plates with the ultra-light feature of the auxetic honeycomb core layer(negative Poisson’s ratio)and reinforced by two laminated three-phase skin layers.The obtained results in our work are compared with other previously published to confirm accuracy and reliability.In addition,the effects of parameters such as geometrical and material parameters on the vibration characteristics of sandwich plates with an auxetic honeycomb core and laminated three-phase skin layers are fully investigated. 展开更多
关键词 Laminated three-phase Sandwich plate Auxetic honeycomb ES-MITC3 element High-order shear deformation theory
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Enhancing ammonia production rates from electrochemical nitrogen reduction by engineering three-phase boundary with phosphorus-activated Cu catalysts
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作者 Jeehye Kim Cho Hee Lee +5 位作者 Yong Hyun Moon Min Hee Lee Eun Hyup Kim Sun Hee Choi Youn Jeong Jang Jae Sung Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期394-401,共8页
Electrochemical N_(2) reduction reaction(eNRR) over Cu-based catalysts suffers from an intrinsically low activity of Cu for activation of stable N_(2) molecules and the limited supply of N_(2) to the catalyst due to i... Electrochemical N_(2) reduction reaction(eNRR) over Cu-based catalysts suffers from an intrinsically low activity of Cu for activation of stable N_(2) molecules and the limited supply of N_(2) to the catalyst due to its low solubility in aqueous electrolytes.Herein,we propose phosphorus-activated Cu electrocatalysts to generate electron-deficient Cu sites on the catalyst surface to promote the adsorption of N_(2) molecules.The eNRR system is further modified using a gas diffusion electrode(GDE) coated with polytetrafluoroethylene(PTFE) to form an effective three-phase boundary of liquid water-gas N_(2)-solid catalyst to facilitate easy access of N_(2) to the catalytic sites.As a result,the new catalyst in the flow-type cell records a Faradaic efficiency of 13.15% and an NH_(3) production rate of 7.69 μg h^(-1) cm^(-2) at-0.2 V_(RHE),which represent 3.56 and 59.2 times increases from those obtained with a pristine Cu electrode in a typical electrolytic cell.This work represents a successful demonstration of dual modification strategies;catalyst modification and N_(2) supplying system engineering,and the results would provide a useful platform for further developments of electrocatalysts and reaction systems. 展开更多
关键词 Electrochemical nitrogen reduction reaction Ammonia production Phosphorous modified copper electrodes Gas diffusion electrodes three-phase boundary PTFE coating
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Automatic measurement of three-phase contact angles in pore throats based on digital images
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作者 ZANG Chuanzhen WANG Lida +3 位作者 ZHOU Kaihu YU Fuwei JIANG Hanqiao LI Junjian 《Petroleum Exploration and Development》 SCIE 2023年第2期442-449,共8页
With the help of digital image processing technology, an automatic measurement method for the three-phase contact angles in the pore throats of the microfluidic model was established using the microfluidic water flood... With the help of digital image processing technology, an automatic measurement method for the three-phase contact angles in the pore throats of the microfluidic model was established using the microfluidic water flooding experiment videos as the data source. The results of the new method were verified through comparing with the manual measurement data.On this basis, the dynamic changes of the three-phase contact angles under flow conditions were clarified by the contact angles probability density curve and mean value change curve. The results show that, for water-wetting rocks, the mean value of the contact angles is acute angle during the early stage of the water flooding process, and it increases with the displacement time and becomes obtuse angle in the middle-late stage of displacement as the dominant force of oil phase gradually changes from viscous force to capillary force. The droplet flow in the remaining oil occurs in the central part of the pore throats, without three-phase contact angle. The contact angles for the porous flow and the columnar flow change slightly during the displacement and present as obtuse angles in view of mean values, which makes the remaining oil poorly movable and thus hard to be recovered. The mean value of the contact angle for the cluster flow tends to increase in the flooding process, which makes the remaining oil more difficult to be recovered. The contact angles for the membrane flow are mainly obtuse angles and reach the highest mean value in the late stage of displacement, which makes the remaining oil most difficult to be recovered. After displacement, the remaining oils under different flow regimes are just subjected to capillary force, with obtuse contact angles, and the wettability of the pore throat walls in the microfluidic model tends to be oil-wet under the action of crude oil. 展开更多
关键词 microfluidic model water flooding experiment digital image processing three-phase contact angle measure-ment method flow regime of the remaining oil
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Exploring an eco-friendly approach to improve soil tensile behavior and cracking resistance 被引量:1
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作者 Lin Li Chao-Sheng Tang +5 位作者 Jin-Jian Xu Yao Wei Zhi-Hao Dong Bo Liu Xi-Ying Zhang Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4272-4284,共13页
Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey so... Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey soils.To validate the feasibility and efficacy of the proposed approach,direct tensile tests were employed to determine the tensile strength of the compacted soil with different W-OH treatment concentrations and water contents.Desiccation tests were also performed to evaluate the effectiveness of W-OH treatment in enhancing soil tensile cracking resistance.During this period,the effects of W-OH treatment concentration and water content on tensile properties,soil suction and microstructure were investigated.The tensile tests reveal that W-OH treatment has a significant impact on the tensile strength and failure mode of the soil,which not only effectively enhances the tensile strength and failure displacement,but also changes the brittle failure behavior into a more ductile quasi-brittle failure behavior.The suction measurements and mercury intrusion porosimetry(MIP)tests show that W-OH treatment can slightly reduce soil suction by affecting skeleton structure and increasing macropores.Combined with the microstructural analysis,it becomes evident that the significant improvement in soil tensile behavior through W-OH treatment is mainly attributed to the W-OH gel's ability to provide additional binding force for bridging and encapsulating the soil particles.Moreover,desiccation tests demonstrate that W-OH treatment can significantly reduce or even inhibit the formation of soil tensile cracking.With the increase of W-OH treatment concentration,the surface crack ratio and total crack length are significantly reduced.This study enhances a fundamental understanding of eco-polymer impacts on soil mechanical properties and provides valuable insight into their potential application for improving soil crack resistance. 展开更多
关键词 Clayey soil Tensile strength Eco-friendly approach Direct tensile test Desiccation cracking Crack resistance
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Application of CD34 expression combined with three-phase dynamic contrast-enhanced computed tomography scanning in preoperative staging of gastric cancer
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作者 Hua Liu Kang-Yan Zhao 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第11期2513-2524,共12页
BACKGROUND Accurate preoperative staging of gastric cancer(GC),a common malignant tumor worldwide,is critical for appropriate treatment plans and prognosis.Dynamic three-phase enhanced computed tomography(CT)scanning ... BACKGROUND Accurate preoperative staging of gastric cancer(GC),a common malignant tumor worldwide,is critical for appropriate treatment plans and prognosis.Dynamic three-phase enhanced computed tomography(CT)scanning for preoperative staging of GC has limitations in evaluating tumor angiogenesis.CD34,a marker on vascular endothelial cell surfaces,is promising in evaluating tumor angiogenesis.We explored the value of their combination for preoperative staging of GC to improve the efficacy and prognosis of patients with GC.Medical records of 106 patients with GC treated at the First People's Hospital of Lianyungang between February 2021 and January 2023 were retrospectively studied.All patients underwent three-phase dynamic contrast-enhanced CT scanning before surgery,and CD34 was detected in gastroscopic biopsy specimens.Using surgical and pathological results as the gold standard,the diagnostic results of three-phase dynamic contrast-enhanced CT scanning at different T and N stages were analyzed,and the expression of CD34-marked microvessel density(MVD)at different T and N stages was determined.The specificity and sensitivity of three-phase dynamic contrast-enhanced CT and CD34 in T and N staging were calculated;those of the combined diagnosis of the two were evaluated in parallel.Independent factors affecting lymph node metastasis were analyzed using multiple logistic regression.RESULTS The accuracy of three-phase dynamic contrast-enhanced CT scanning in diagnosing stages T1,T2,T3 and T4 were 68.00%,75.00%,79.41%,and 73.68%,respectively,and for diagnosing stages N0,N1,N2,and N3 were 75.68%,74.07%,85.00%,and 77.27%,respectively.CD34-marked MVD expression increased with increasing T and N stages.Specificity and sensitivity of three-phase dynamic contrast-enhanced CT in T staging were 86.79%and 88.68%;for N staging,89.06%and 92.86%;for CD34 in T staging,64.15%and 88.68%;and for CD34 in N staging,84.38%and 78.57%,respectively.Specificity and sensitivity of joint diagnosis in T staging were 55.68%and 98.72%,and N staging were 75.15%and 98.47%,respectively,with the area under the curve for diagnosis improving accordingly.According to multivariate analysis,a longer tumor diameter,higher pathological T stage,lower differ-entiation degree,and higher expression of CD34-marked MVD were independent risk factors for lymph node metastasis in patients with GC.CONCLUSION With high accuracy in preoperatively determining the invasion depth and lymph node metastasis of GC,CD34 expression and three-phase dynamic contrast-enhanced CT can provide a reliable basis for surgical resection. 展开更多
关键词 CD34 three-phase dynamic contrast-enhanced computed tomography scanning Gastric cancer Preoperative staging INVASION Lymph node metastasis
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Laparoscopic left hemihepatectomy guided by indocyanine green fluorescence: A cranial-dorsal approach 被引量:1
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作者 Xing-Ru Wang Xiao-Ju Li +6 位作者 Dan-Dan Wan Qian Zhang Tian-Xi Liu Zong-Wen Shen Hong-Xing Tong Yan Li Jian-Wei Li 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期409-418,共10页
BACKGROUND Advancements in laparoscopic technology and a deeper understanding of intra-hepatic anatomy have led to the establishment of more precise laparoscopic hepatectomy(LH)techniques.The indocyanine green(ICG)flu... BACKGROUND Advancements in laparoscopic technology and a deeper understanding of intra-hepatic anatomy have led to the establishment of more precise laparoscopic hepatectomy(LH)techniques.The indocyanine green(ICG)fluorescence navi-gation technique has emerged as the most effective method for identifying hepatic regions,potentially overcoming the limitations of LH.While laparoscopic left hemihepatectomy(LLH)is a standardized procedure,there is a need for innova-tive strategies to enhance its outcomes.important anatomical markers,surgical skills,and ICG staining methods.METHODS Thirty-seven patients who underwent ICG fluorescence-guided LLH at Qujing Second People's Hospital between January 2019 and February 2022 were retrospectively analyzed.The cranial-dorsal approach was performed which involves dissecting the left hepatic vein cephalad,isolating the Arantius ligament,exposing the middle hepatic vein,and dissecting the parenchyma from the dorsal to the foot in order to complete the anatomical LLH.The surgical methods,as well as intra-and post-surgical data,were recorded and analyzed.Our hospital’s Medical Ethics Committee approved this study(Ethical review:2022-019-01).RESULTS Intraoperative blood loss during LLH was 335.68±99.869 mL and the rates of transfusion and conversion to laparotomy were 13.5%and 0%,respectively.The overall incidence of complications throughout the follow-up(median of 18 months;range 1-36 months)was 21.6%.No mortality or severe complications(level IV)were reported.CONCLUSION LLH has the potential to become a novel,standardized approach that can effectively,safely,and simply expose the middle hepatic vein and meet the requirements of precision surgery. 展开更多
关键词 Laparoscopic left hemihepatectomy Indocyanine green Cranial-dorsal approach Laparoscopic hepatectomy Arantius ligament Glissonean pedicle
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Which approach of total hip arthroplasty is the best efficacy and least complication? 被引量:1
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作者 Lertkong Nitiwarangkul Natthapong Hongku +3 位作者 Oraluck Pattanaprateep Sasivimol Rattanasiri Patarawan Woratanarat Ammarin Thakkinstian 《World Journal of Orthopedics》 2024年第1期73-93,共21页
BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications o... BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications of hip approaches remains inconclusive.This study conducted an umbrella review to systematically appraise previous meta-analysis(MAs)including conventional posterior approach(PA),and minimally invasive surgeries as the lateral approach(LA),direct anterior approach(DAA),2-incisions method,mini-lateral approach and the newest technique direct superior approach(DSA)or supercapsular percutaneouslyassisted total hip(SuperPath).AIM To compare the efficacy and complications of hip approaches that have been published in all MAs and randomized controlled trials(RCTs).METHODS MAs were identified from MEDLINE and Scopus from inception until 2023.RCTs were then updated from the latest MA to September 2023.This study included studies which compared hip approaches and reported at least one outcome such as Harris Hip Score(HHS),dislocation,intra-operative fracture,wound compliData were independently selected,extracted and assessed by two reviewers.Network MA and cluster rank and surface under the cumulative ranking curve(SUCRA)were estimated for treatment efficacy and safety.RESULTS Finally,twenty-eight MAs(40 RCTs),and 13 RCTs were retrieved.In total 47 RCTs were included for reanalysis.The results of corrected covered area showed high degree(13.80%).Among 47 RCTs,most of the studies were low risk of bias in part of random process and outcome reporting,while other domains were medium to high risk of bias.DAA significantly provided higher HHS at three months than PA[pooled unstandardized mean difference(USMD):3.49,95%confidence interval(CI):0.98,6.00 with SUCRA:85.9],followed by DSA/SuperPath(USMD:1.57,95%CI:-1.55,4.69 with SUCRA:57.6).All approaches had indifferent dislocation and intraoperative fracture rates.SUCRA comparing early functional outcome and composite complications(dislocation,intra-operative fracture,wound complication,and nerve injury)found DAA was the best approach followed by DSA/SuperPath.CONCLUSION DSA/SuperPath had better earlier functional outcome than PA,but still could not overcome the result of DAA.This technique might be the other preferred option with acceptable complications. 展开更多
关键词 Total hip arthroplasty Total hip replacement approach Supercapsular percutaneously-assisted total hip Harris Hip Score Intra-operative fracture
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Minimalistic approach to left atrial appendage occlusion guided by cardiac computed tomography angiography
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作者 Xian-Sai MENG Qing-Song WANG +7 位作者 Xin-Yan WANG Xu LU Yang MU Jing WANG Ting-Ting SONG Yun-Dai CHEN Tao CHEN Jun GUO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第4期431-442,共12页
OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who unde... OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who underwent LAAO, with or without CCTA-guided, were matched(1:2). Each step of the LAAO procedure in the computed tomography(CT) guidance group(CT group) was directed by preprocedural CT planning. In the control group, LAAO was performed using the standard method. All patients were followed up for 12 months, and device surveillance was conducted using CCTA.RESULTS A total of 90 patients were included in the analysis, with 30 patients in the CT group and 60 matched patients in the control group. All patients were successfully implanted with Watchman devices. The mean ages for the CT group and the control group were 70.0 ± 9.4 years and 68.4 ± 11.9 years(P = 0.52), respectively. The procedure duration(45.6 ± 10.7 min vs. 58.8 ± 13.0 min,P < 0.001) and hospital stay(7.5 ± 2.4 day vs. 9.6 ± 2.8 day, P = 0.001) in the CT group was significantly shorter compared to the control group. However, the total radiation dose was higher in the CT group compared to the control group(904.9 ± 348.0 m Gy vs.711.9 ± 211.2 m Gy, P = 0.002). There were no significant differences in periprocedural pericardial effusion(3.3% vs. 6.3%, P = 0.8) between the two groups. The rate of postprocedural adverse events(13.3% vs. 18.3%, P = 0.55) were comparable between both groups at 12 months follow-up.CONCLUSIONS CCTA is capable of detailed LAAO procedure planning. Minimalistic LAAO with preprocedural CCTA planning was feasible and safe, with shortened procedure time and acceptable increased radiation and contras consumption. For patients with contraindications to general anesthesia and/or transesophageal echocardiography, this promising method may be an alternative to conventional LAAO. 展开更多
关键词 ANESTHESIA matched approach
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Virtual source approach for maximizing resolution in high-penetration gamma-ray imaging
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作者 Yuchi Wu Shaoyi Wang +14 位作者 Bin Zhu Yonghong Yan Minghai Yu Gang Li Xiaohui Zhang Yue Yang Fang Tan Feng Lu Bi Bi Xiaoqin Mao Zhonghai Wang Zongqing Zhao Jingqin Su Weimin Zhou Yuqiu Gu 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第3期19-30,共12页
High-energy gamma-ray radiography has exceptional penetration ability and has become an indispensable nondestructive testing(NDT)tool in various fields.For high-energy photons,point projection radiography is almost th... High-energy gamma-ray radiography has exceptional penetration ability and has become an indispensable nondestructive testing(NDT)tool in various fields.For high-energy photons,point projection radiography is almost the only feasible imaging method,and its spatial resolution is primarily constrained by the size of the gamma-ray source.In conventional industrial applications,gamma-ray sources are commonly based on electron beams driven by accelerators,utilizing the process of bremsstrahlung radiation.The size of the gamma-ray source is dependent on the dimensional characteristics of the electron beam.Extensive research has been conducted on various advanced accelerator technologies that have the potential to greatly improve spatial resolution in NDT.In our investigation of laser-driven gamma-ray sources,a spatial resolution of about 90μm is achieved when the areal density of the penetrated object is 120 g/cm^(2).A virtual source approach is proposed to optimize the size of the gamma-ray source used for imaging,with the aim of maximizing spatial resolution.In this virtual source approach,the gamma ray can be considered as being emitted from a virtual source within the convertor,where the equivalent gamma-ray source size in imaging is much smaller than the actual emission area.On the basis of Monte Carlo simulations,we derive a set of evaluation formulas for virtual source scale and gamma-ray emission angle.Under optimal conditions,the virtual source size can be as small as 15μm,which can significantly improve the spatial resolution of high-penetration imaging to less than 50μm. 展开更多
关键词 RESOLUTION approach utilizing
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Debate on direct-anterior vs posterior approach for hip hemiarthroplasty:The authors’insights
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作者 Deepak Kumar Tarkik Thami Manjunath Nishani 《World Journal of Orthopedics》 2024年第5期486-488,共3页
We read and discussed the study entitled“Complication rates after direct anterior vs posterior approach for Hip Hemiarthroplasty in elderly individuals with femoral neck fractures”with great interest.The authors hav... We read and discussed the study entitled“Complication rates after direct anterior vs posterior approach for Hip Hemiarthroplasty in elderly individuals with femoral neck fractures”with great interest.The authors have done justice to the topic of comparison of anterior and posterior surgical approaches for bipolar hemiarthroplasty which has been an everlasting debate in the existing literature.However,there are certain aspects of this study that need clarification from the authors. 展开更多
关键词 COMMENTARY Direct anterior approach Posterior approach Hip hemiarthroplasty
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Direct anterior compared to posterior approach for hip hemiarthroplasty following femoral neck fractures
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作者 Kevin A Wu Alexandra N Krez Albert T Anastasio 《World Journal of Orthopedics》 2024年第6期605-607,共3页
The differences in complication rates between the direct anterior and posterior approaches for hemiarthroplasty in elderly patients with femoral neck fractures are not yet fully understood.Dislocation,a severe complic... The differences in complication rates between the direct anterior and posterior approaches for hemiarthroplasty in elderly patients with femoral neck fractures are not yet fully understood.Dislocation,a severe complication associated with increased mortality and often requiring additional surgery,may occur less frequently with the direct anterior approach compared to the posterior approach.Careful consideration of patient demographics is essential when planning the surgical approach.Future research in this area should focus on robust randomized controlled trials involving elderly patients recovering from femoral neck fractures. 展开更多
关键词 Direct anterior approach Posterior approach HEMIARTHROPLASTY Femoral neck fractures ARTHROPLASTY DISLOCATION Surgical technique
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A FLEXIBLE OBJECTIVE-CONSTRAINT APPROACH AND A NEW ALGORITHM FOR CONSTRUCTING THE PARETO FRONT OF MULTIOBJECTIVE OPTIMIZATION PROBLEMS
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作者 N.HOSEINPOOR M.GHAZNAVI 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期702-720,共19页
In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized pr... In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems. 展开更多
关键词 multiobjective optimization Pareto front SCALARIZATION objective-constraint approach proper efficient solution
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A Deep Learning Based Broadcast Approach for Image Semantic Communication over Fading Channels
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作者 Ma Kangning Shi Yuxuan +1 位作者 Shao Shuo Tao Meixia 《China Communications》 SCIE CSCD 2024年第7期78-94,共17页
We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adapt... We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adaptive semantic transmission in terms of different channel states.We combine the classic broadcast approach with the image transformer to implement this adaptive joint source and channel coding(JSCC)scheme.Specifically,we utilize the neural network(NN)to jointly optimize the hierarchical image compression and superposition code mapping within this scheme.The learned transformers and codebooks allow recovering of the image with an adaptive quality and low error rate at the receiver side,in each channel state.The simulation results exhibit our proposed scheme can dynamically adapt the coding to the current channel state and outperform some existing intelligent schemes with the fixed coding block. 展开更多
关键词 broadcast approach deep learning fading channels semantic communication
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