期刊文献+
共找到667篇文章
< 1 2 34 >
每页显示 20 50 100
The Design and Implementation of a Biomechanics-Driven Structural Safety Monitoring System for Offshore Wind Power Step-Up Stations
1
作者 Ruigang Zhang Qihui Yan +3 位作者 Jialiang Wang Hao Wang Jie Sun Junjiao Shi 《Energy Engineering》 2025年第9期3609-3624,共16页
As the core facility of offshore wind power systems,the structural safety of offshore booster stations directly impacts the stable operation of entire wind farms.With the global energy transition toward green and lowc... As the core facility of offshore wind power systems,the structural safety of offshore booster stations directly impacts the stable operation of entire wind farms.With the global energy transition toward green and lowcarbon goals,offshore wind power has emerged as a key renewable energy source,yet its booster stations face harsh marine environments,including persistent wave impacts,salt spray corrosion,and equipment-induced vibrations.Traditional monitoring methods relying on manual inspections and single-dimensional sensors suffer from critical limitations:low efficiency,poor real-time performance,and inability to capture millinewton-level stress fluctuations that signal early structural fatigue.To address these challenges,this study proposes a biomechanics-driven structural safety monitoring system integrated with deep learning.Inspired by biological stress-sensing mechanisms,the system deploys a distributedmulti-dimensional force sensor network to capture real-time stress distributions in key structural components.A hybrid convolutional neural network-radial basis function(CNN-RBF)model is developed:the CNN branch extracts spatiotemporal features from multi-source sensing data,while the RBF branch reconstructs the nonlinear stress field for accurate anomaly diagnosis.The three-tier architectural design—data layer(distributed sensor array),function layer(CNN-RBF modeling),and application layer(edge computing terminal)—enables a closedloop process from high-resolution data collection to real-time early warning,with data processing delay controlled within 200 ms.Experimental validation against traditional SOM-based systems demonstrates significant performance improvements:monitoring accuracy increased by 19.8%,efficiency by 23.4%,recall rate by 20.5%,and F1 score by 21.6%.Under extreme weather(e.g.,typhoons and winter storms),the system’s stability is 40% higher,with user satisfaction improving by 17.2%.The biomechanics-inspired sensor design enhances survival rates in salt fog(85.7%improvement)and dynamic loads,highlighting its robust engineering applicability for intelligent offshore wind farm maintenance. 展开更多
关键词 BIOMECHANICS offshore wind power step-up station safety monitoring system
在线阅读 下载PDF
Research on the Selection and Layout Scheme of Main Transformers in the Primary Electrical Design of New Energy Step-Up Stations
2
作者 Yuekai Liao 《Journal of Electronic Research and Application》 2025年第4期254-260,共7页
This paper focuses on the research of the main transformer selection and layout scheme for new energy step-up substations.From the perspective of engineering design,it analyzes the principles of main transformer selec... This paper focuses on the research of the main transformer selection and layout scheme for new energy step-up substations.From the perspective of engineering design,it analyzes the principles of main transformer selection,key parameters,and their matching with the characteristics of new energy.It also explores the layout methods and optimization strategies.Combined with typical case studies,optimization suggestions are proposed for the design of main transformers in new energy step-up substations.The research shows that rational main transformer selection and scientific layout schemes can better adapt to the characteristics of new energy projects while effectively improving land use efficiency and economic viability.This study can provide technical experience support for the design of new energy projects. 展开更多
关键词 New energy step-up substation Engineering design Main transformer selection
在线阅读 下载PDF
一种低输入电压、低功率Step-up DC-DC变换器的设计
3
作者 门秀萍 《常州工学院学报》 2011年第5期34-35,45,共3页
文章提出一种Step-up DC-DC的变换器的设计方法,效率高达70%,输入电压范围低至500 mV,最小起动电压能够达到300 mV。
关键词 低输入电压 step-up DC-DC 变换器
在线阅读 下载PDF
One-step laparoscopic pancreatic necrosectomy verse surgical step-up approach for infected pancreatic necrosis:a case-control study 被引量:15
4
作者 Sheng-bo Han Ding Chen +6 位作者 Qing-yong Chen Ping Hu Hai Zheng Jin-huang Chen Peng Xu Chun-you Wang Gang Zhao 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2022年第4期274-282,共9页
BACKGROUND:The surgical step-up approach often requires multiple debridements and might not be suitable for infected pancreatic necrosis(IPN)patients with various abscesses or no safe route for percutaneous catheter d... BACKGROUND:The surgical step-up approach often requires multiple debridements and might not be suitable for infected pancreatic necrosis(IPN)patients with various abscesses or no safe route for percutaneous catheter drainage(PCD).This case-control study aimed to investigate the safety and effectiveness of one-step laparoscopic pancreatic necrosectomy(LPN)in treating IPN.METHODS:This case-control study included IPN patients undergoing one-step LPN or surgical step-up in our center from January 2015 to December 2020.The short-term and long-term complications after surgery,length of hospital stay,and postoperative ICU stays in both groups were analyzed.Univariate and multivariate logistic regression analyses were performed to explore the risk factors of major complications or death.RESULTS:A total of 53 IPN patients underwent one-step LPN and 37 IPN patients underwent surgical step-up approach in this study.There was no significant difference in the incidence of death,major complications,new-onset diabetes,or new-onset pancreatic exocrine insufficiency between the two groups.However,the length of hospital stay in the one-step LPN group was significantly shorter than that in the surgical step-up group.Univariate regression analysis showed that the surgical approach(one-step/step-up)was not the risk factor for major complications or death.Multivariate logistic regression analysis indicated that computed tomography(CT)severity index,American Society of Anesthesiologists(ASA)class IV,and white blood cell(WBC)were the significant risk factors for major complications or death.CONCLUSION:One-step LPN is as safe and effective as the surgical step-up approach for treating IPN patients,and reduces total hospital stay. 展开更多
关键词 Infected pancreatic necrosis One-step laparoscopic pancreatic necrosectomy Surgical step-up approach
暂未订购
Mortality and morbidity in necrotizing pancreatitis managed on principles of step-up approach:7 years experience from a single surgical unit 被引量:12
5
作者 Deshpande Aparna Sunil Kumar Shukla Kamalkumar 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2017年第10期200-208,共9页
AIM To determine percentage of patients of necrotizing pancreatitis(NP) requiring intervention and the types of interventions performed. Outcomes of patients of step up necrosectomy to those of direct necrosectomy wer... AIM To determine percentage of patients of necrotizing pancreatitis(NP) requiring intervention and the types of interventions performed. Outcomes of patients of step up necrosectomy to those of direct necrosectomy were compared. Operative mortality, overall mortality, morbidity and overall length of stay were determined. METHODS After institutional ethics committee clearance and waiver of consent, records of patients of pancreatitis were reviewed. After excluding patients as per criteria, epidemiologic and clinical data of patients of NP was noted. Treatment protocol was reviewed. Data of patients in whom stepup approach was used was compared to those in whom it was not used. RESULTS A total of 41 interventions were required in 39% patients. About 60% interventions targeted the pancreatic necrosis while the rest were required to deal with the complications of the necrosis. Image guided percutaneous catheter drainage was done in 9 patients for infected necrosis all of whom required further necrosectomy and in 3 patients with sterile necrosis. Direct retroperitoneal or anterior necrosectomy was performed in 15 patients. The average time to first intervention was 19.6 d in the non step-up group(range 11-36) vs 18.22 d in the Step-up group(range 13-25). The average hospital stay in non step-up group was 33.3 d vs 38 d in step up group. The mortality in the step-up group was 0%(0/9) vs 13%(2/15) in the non step up group. Overall mortality was 10.3% while post-operative mortality was 8.3%. Average hospital stay was 22.25 d.CONCLUSION Early conservative management plays an important role in management of NP. In patients who require intervention, the approach used and the timing of intervention should be based upon the clinical condition and local expertise available. Delaying intervention and use of minimal invasive means when intervention is necessary is desirable. The step-up approach should be used whenever possible. Even when the classical retroperitoneal catheter drainage is not feasible, there should be an attempt to follow principles of step-up technique to buy time. The outcome of patients in the step-up group compared to the non stepup group is comparable in our series. Interventions for bowel diversion, bypass and hemorrhage control should be done at the appropriate times. 展开更多
关键词 Necrotizing pancreatitis Nerosectomy Morbidity and mortality in necrotizing pancreatitis step-up approach
暂未订购
Controversies in the treatment of Crohn’s disease: The case for an accelerated step-up treatment approach 被引量:4
6
作者 Amandeep K Shergill Jonathan P Terdiman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第17期2670-2677,共8页
The ideal treatment strategy for Crohn’s disease (CD) remains uncertain, as does the optimal endpoint of therapy. Top-down versus step-up describes two different approaches: early use of immunomodulators and biologic... The ideal treatment strategy for Crohn’s disease (CD) remains uncertain, as does the optimal endpoint of therapy. Top-down versus step-up describes two different approaches: early use of immunomodulators and biological agents in the former versus initial treatment with steroids in the latter, with escalation to immunomodulators or biological drugs in patients proven to be steroid refractory or steroid dependent. Top-down therapy has been associated with higher rates of mucosal healing. If mucosal healing proves to be associated with better long-term outcomes, such as a decreased need for hospitalization and surgery, top-down therapy may be the better approach for many patients. The main concern with the top-down approach is the toxicity of the immunomodulators and biological agents, which have been linked with infectious complications as well as an increased risk of lymphoma. It is unlikely that one strategy will be best for all patients given the underlying heterogeneity of CD presentation and severity. Ultimately, we must weigh the safety and efficacy of the therapies with the risks of the disease itself. Unfortunately our ability to risk stratify patients at diagnosis remains rudimentary. The purpose of this paper is to review the data that supports or refutes the differing treatment paradigms in CD, and to provide a rationale for an approach, termed the "accelerated step-up" approach, which attempts to balance the risks and benefits of our currently available therapies with the risk of disease related complications as we understand them in 2008. 展开更多
关键词 Crohn's disease TOP-DOWN step-up Anti-tumor necrosis factor antibodies IMMUNOMODULATORS Mucosal healing
暂未订购
Step-up approach in emphysematous hepatitis: A case report 被引量:1
7
作者 Silke Francois Maridi Aerts +4 位作者 Hendrik Reynaert Ruth Van Lancker Johan Van Laethem Rastislav Kunda Nouredin Messaoudi 《World Journal of Hepatology》 2022年第2期464-470,共7页
BACKGROUND Emphysematous hepatitis(EH)is a rare,rapidly progressive fulminant gasforming infection of the liver parenchyma.It is often fatal and mostly affects diabetes patients.CASE SUMMARY We report a case of EH suc... BACKGROUND Emphysematous hepatitis(EH)is a rare,rapidly progressive fulminant gasforming infection of the liver parenchyma.It is often fatal and mostly affects diabetes patients.CASE SUMMARY We report a case of EH successfully managed by a step-up approach consisting of aggressive hemodynamic support,intravenous antibiotics,and percutaneous drainage,ultimately followed by laparoscopic deroofing.Of 11 documented cases worldwide,only 1 of the patients survived,treated by urgent laparotomy and surgical debridement.CONCLUSION EH is a life-threatening infection.Its high mortality rate makes timely diagnosis essential,in order to navigate treatment accordingly. 展开更多
关键词 Emphysematous hepatitis Septic shock step-up approach Percutaneous drainage Laparoscopic deroofing Case report
暂未订购
Comparison Analysis of Efficiency Between Double-Synchronous Step-Down-Stress and Step-Up-Stress Accelerated Life Tests 被引量:1
8
作者 寇海霞 安宗文 孙道明 《Journal of Shanghai Jiaotong university(Science)》 EI 2017年第3期361-364,共4页
Double-crossed-step-stress(DCSS) accelerated life test(ALT) method is widely used for estimating the lifetime of products with high reliability and long lifetime. In order to further reduce the test time and test cost... Double-crossed-step-stress(DCSS) accelerated life test(ALT) method is widely used for estimating the lifetime of products with high reliability and long lifetime. In order to further reduce the test time and test cost, a double-synchronous-step-stress(DSSS) ALT method which combines a double-synchronous-step-downstress(DSSDS) ALT method and a double-synchronous-step-up-stress(DSSUS) ALT method is proposed. The accelerated stresses decrease and increase in a synchronous way with one step in the DSSDS-ALT and DSSUSALT methods, respectively. Monte Carlo method is adopted to simulate the two methods, and the validity and efficiency of them are demonstrated by the simulation results. In addition, a comparison analysis of efficiency between DSSDS-ALT method and DSSUS-ALT method is carried out. The result shows that the DSSDS-ALT method compared with the DSSUS-ALT method can significantly improve the test efficiency under the same test condition. 展开更多
关键词 accelerated life test(ALT) double-synchronous-step-down-stress(DSSDS) double-synchronous-step-up-stress(DSSUS) efficiency Monte Carlo
原文传递
Fuzzy Based Interleaved Step-up Converter for Electric Vehicle
9
作者 T.Saravanakumar R.Saravana kumar 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期1103-1118,共16页
This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The pro... This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The proposed ISC direct current(DC-DC)converter could also be used in automobiles,satellites,industries,and propulsion.To enhance voltage gain,the proposed ISC Converter combines boost converter and interleaved converter(IC).This design also reduces the number of switches.As a result,ISC converter switching losses are reduced.The proposed ISC Converter topology can produce a 143 V output voltage and 1 kW of power.Due to the high voltage gain of this converter design,it is suitable for medium and high-power systems.The proposed ISC Converter topology is simulated in MATLAB/Simulink.The simulated output displays a high output voltage.But the output voltage contains maximum ripples.Fuzzy proposes an ISC Converter which makes closed loop responsiveness and reduces the output voltage ripple.The proposed ISC converter has the lowest ripple output voltage,which is less than 2%,because the duty cycle is regulated using the fuzzy logic controller.It offers high voltage gain,minimal ripple,and low switching loss.The performance of the proposed converter is compared to that of the fuzzy and Pro-portional Integral(PI)controllers implemented in MATLAB. 展开更多
关键词 step-up converter interleaved converter ripple voltage FUZZY electric vehicles
在线阅读 下载PDF
Analysis and Design of Single Switch Hybrid Step-Up Converter
10
作者 Ravivarman Shanmugasundaram Jeyabharath Rajaiah Veena Parasunath 《Circuits and Systems》 2016年第4期211-221,共11页
A Single Switch Hybrid Step-up Converter with high voltage gain, which is suitable for renewable energy system, is proposed in this paper. The proposed converter consists of one switched diode-inductor cell and a capa... A Single Switch Hybrid Step-up Converter with high voltage gain, which is suitable for renewable energy system, is proposed in this paper. The proposed converter consists of one switched diode-inductor cell and a capacitor. While switching, both are charged in parallel from the input source and discharged in series to the output. In order to obtain extra voltage gain at lower duty cycle, the voltage multiplier cell is integrated with the proposed converter. The main advantages of the converter are high voltage gain, reduced voltage stress, simple structure and low output voltage ripples. The operating principle and steady state theoretical analysis are presented. A 250 W prototype converter is implemented with 12 V input and 120 V output to verify the design and analysis of this converter and it has an efficiency of over 90% in all operations. 展开更多
关键词 DC-DC Power Conversion Switched-Inductor step-up Converter Voltage Multiplier
在线阅读 下载PDF
基于"Step-up"策略下四步法治疗感染性胰腺坏死的临床研究 被引量:21
11
作者 张奇 李乐 +6 位作者 吕新建 陈宏泽 陈华 孔瑞 王刚 姜洪池 孙备 《中华外科杂志》 CAS CSCD 北大核心 2020年第11期858-863,共6页
目的探讨以小切口胰腺坏死组织清除术(非视频辅助)为核心的"四步法"治疗感染性胰腺坏死(IPN)的临床效果。方法回顾性分析2013年1月至2017年12月哈尔滨医科大学附属第一医院胰胆外科收治的207例IPN患者的临床资料,其中男性132... 目的探讨以小切口胰腺坏死组织清除术(非视频辅助)为核心的"四步法"治疗感染性胰腺坏死(IPN)的临床效果。方法回顾性分析2013年1月至2017年12月哈尔滨医科大学附属第一医院胰胆外科收治的207例IPN患者的临床资料,其中男性132例(63.8%),女性75例(36.2%);中位年龄45岁(范围:19~80岁)。重症急性胰腺炎158例(76.3%),中重症急性胰腺炎49例(23.7%)。所有患者均先接受经皮置管引流(PCD)治疗。Step-up组(173例):采用"四步法"治疗策略,PCD后接受微创小切口胰腺坏死清除术(MIAPN),对于术后残余感染灶进一步行经窦道内镜下坏死清除术和(或)PCD,最后行常规开放胰腺坏死清除术(OPN);OPN组(34例):PCD无效后直接行OPN。比较两组患者围手术期情况及预后。正态分布的计量资料采用t检验进行分析,偏态分布的计量资料采用Wilcoxon秩和检验进行分析;计数资料采用χ^2检验或Fisher确切概率法进行分析。结果Step-up组与OPN组患者基本特征的差异均无统计学意义(P值均>0.05)。OPN组的转诊率、术前3 d器官功能衰竭发生率高于Step-up组(47.1%比28.9%,χ^2=4.313,P=0.038;26.5%比9.2%,χ^2=2.819,P=0.011)。Step-up组MIAPN术前PCD次数、PCD管留置数量较OPN组明显减少[1(1)次比2(1)次;Z=-3.373,P=0.018;2(1)根比3(2)根;Z=-2.208,P=0.027]。与OPN组相比,Step-up组发病至手术时间缩短[29(15)d比36(17)d,Z=-0.567,P=0.008],MIAPN手术时间缩短[58(27)min比90(56)min;Z=-3.908,P<0.01];术后病死率降低(5.8%比17.6%;χ^2=4.070,P=0.044),术后总体并发症发生率降低(23.1%比55.9%;χ^2=14.960,P<0.01),术后新发器官功能衰竭比例降低(37.5%比47.4%;χ^2=7.133,P=0.007),但两组术后腹腔局部并发症(胰瘘、腹腔内出血、消化道瘘)发生率的差异均无统计学意义(P值均>0.05)。Step-up组术后需要ICU治疗的患者比例小于OPN组(22.0%比44.1%,χ^2=6.204,P=0.013);Step-up组总住院时间较OPN组明显缩短[46(13)d比52(13)d,Z=-1.993,P=0.046]。结论"四步法"微创治疗感染性胰腺坏死的初步临床效果满意,微创小切口胰腺坏死组织清除术治疗IPN简单、安全、有效。 展开更多
关键词 胰腺炎 急性坏死性 感染性胰腺坏死 经皮穿刺置管引流 小切口胰腺坏死组织清除术 创伤递升式
原文传递
具有2种可选拓扑的柔性DC-DC变换器研究
12
作者 赵猛 付明 +3 位作者 李亚飞 马千里 朱庆 刘乙 《电源学报》 北大核心 2026年第2期71-79,共9页
本文提出一种具有4个输出端子的柔性DC-DC变换器。根据输出端子之间不同的连接方式,该变换器可在三电平Boost和图腾柱Boost这2种拓扑之间切换。分析2种拓扑的工作模态和稳态特性,讨论各自适合的应用场景以及切换的条件和实现方式。分析... 本文提出一种具有4个输出端子的柔性DC-DC变换器。根据输出端子之间不同的连接方式,该变换器可在三电平Boost和图腾柱Boost这2种拓扑之间切换。分析2种拓扑的工作模态和稳态特性,讨论各自适合的应用场景以及切换的条件和实现方式。分析并验证图腾柱Boost拓扑具有大升压比的特点。在PSIM仿真环境搭建电路模型,设计元件参数并给出相关仿真结果。对1台峰值效率为98.5%的640 W硬件样机进行测试,并给出部分关键波形。仿真和硬件实验结果表明,该柔性DC-DC变换器具有应用灵活、电路结构较为简单以及效率较高的特点。 展开更多
关键词 柔性变换器 三电平Boost 图腾柱Boost 大升压比
在线阅读 下载PDF
一种零输入电流纹波高升压软开关DC-DC变换器
13
作者 周明珠 刘超 +2 位作者 庄一展 毛行奎 张艺明 《仪器仪表学报》 北大核心 2026年第1期25-36,共12页
高升压DC-DC变换器广泛应用于光伏(PV)发电、燃料电池、直流微电网和混合动力电动汽车等领域。本研究提出了一种零输入电流纹波(ZICR)高升压软开关DC-DC变换器。其通过将输入电感电压箝位在零电压的方式实现ZICR,有效消除输入电流纹波;... 高升压DC-DC变换器广泛应用于光伏(PV)发电、燃料电池、直流微电网和混合动力电动汽车等领域。本研究提出了一种零输入电流纹波(ZICR)高升压软开关DC-DC变换器。其通过将输入电感电压箝位在零电压的方式实现ZICR,有效消除输入电流纹波;较低的输入电流纹波可提高光伏电池板和燃料电池的发电效率和使用寿命。该变换器通过引入耦合电感和开关电容升压技术来实现高电压增益,利用开关管导通占空比和耦合电感匝比灵活调节输出电压。同时,该变换器中所有开关都实现了零电压开关(ZVS),所有二极管都实现了零电流开关(ZCS),这样可以降低开关的开关损耗和二极管的反向恢复损耗,进而降低开关器件的损耗来提高变换器的工作效率。详细分析了变换器的工作原理、ZICR特性、电压电流应力和软开关特性,并将所提ZICR变换器与其它相似的高升压DC-DC变换器进行了性能参数比较。最后,搭建了一台100 kHz、200 W、38~380 V的实验样机,验证了所提ZICR变换器在额定功率下的拓扑结构性能和理论分析的正确性。同时,在额定功率下具有ZICR和不具有ZICR的变换器的实验效率分别为95.4%和96.1%。实验结果表明该ZICR变换器具有良好的稳态性能,能够实现高电压增益和高效率输出,满足新能源与直流微电网之间的功率变换应用需求,是一种性能优越的高升压DC-DC变换器拓扑。 展开更多
关键词 高升压DC-DC变换器 零输入电流纹波 耦合电感 零电压开关 零电流开关
原文传递
MDT模式下升阶梯与跨阶梯策略治疗重症急性胰腺炎合并感染性胰腺坏死的效果对比
14
作者 杨皓雯 彭雄兵 +3 位作者 梁梅香 贺坤华 李月宏 方兴保 《肝胆胰外科杂志》 2026年第2期77-83,共7页
目的探讨多学科团队(MDT)模式下升阶梯(Step-up)与跨阶梯(Step-jump)策略治疗重症急性胰腺炎(SAP)合并感染性胰腺坏死(IPN)的效果对比。方法回顾性分析2021年1月至2024年6月期间曲靖市第一人民医院收治的57例SAP合并IPN患者的临床资料,... 目的探讨多学科团队(MDT)模式下升阶梯(Step-up)与跨阶梯(Step-jump)策略治疗重症急性胰腺炎(SAP)合并感染性胰腺坏死(IPN)的效果对比。方法回顾性分析2021年1月至2024年6月期间曲靖市第一人民医院收治的57例SAP合并IPN患者的临床资料,经MDT评估后分为两组,Step-up组(n=35)采用升阶梯策略治疗,Step-jump组(n=22)采用跨阶梯策略治疗。采用独立样本t检验、Mann-Whitney U和χ^(2)检验比较两组患者手术时间,术中出血量及输血情况,术后抗生素使用时间和引流管拔除时间,住院时间,术后生命体征、实验室检查、影像学检查等指标和并发症发生情况;采用Kaplan-Meier法绘制两组患者的生存曲线。结果57例患者中,3例拒绝手术,54例接受手术治疗,术后48~72 h生命体征均恢复稳定。Step-jump组与Step-up组患者相比,手术时间延长[145.0(104.0,186.0)min vs 97.0(65.0,130.0)min,P=0.041],术中出血量增加[130.0(80.0,180.0)m L vs 60.0(40.0,80.0)m L,P<0.001],差异有统计学意义。两组患者在术后第3天C反应蛋白(CRP)[(127.8±44.9)mg/L vs(118.3±52.9)mg/L]、术后第3天白细胞计数(WBC)[(13.1±3.1)×10^(9)/L vs(12.8±2.6)×10^(9)/L]、抗生素使用时间[(12.5±2.0)d vs(13.2±4.1)d]、总体并发症发生率[12.1%(4/33)vs 14.3%(3/21)]方面比较,差异无统计学意义(均P>0.05)。两组患者在总住院时间、ICU住院时间、引流管拔除时间、术后生命体征转归时间等方面比较,差异无统计学意义(P>0.05)。术后影像学随访提示两组患者胰周病变均明显改善。Step-jump组和Step-up组患者术后30 d累积生存率分别为95.5%、94.3%。结论根据MDT评估结果对SAP合并IPN患者选取升阶梯或跨阶梯策略进行治疗,均有较好的临床效果和安全性。 展开更多
关键词 重症急性胰腺炎 感染性胰腺坏死 多学科团队 综合诊疗 升阶梯 跨阶梯
暂未订购
某电站升压变充电过程中铁磁谐振的分析和探讨
15
作者 谭斌忠 龙天腾 +3 位作者 王应 何泽胜 张鹏飞 邓锋 《上海大中型电机》 2026年第1期22-26,共5页
升压变铁心存在剩磁时进行充电操作,在励磁涌流和操作电压波动的激励作用下,可能会引发铁磁谐振,对升压变及其相连的电压互感器产生不利影响,降低厂站设备的供电可靠性。本文对某电站升压变充电过程中产生的铁磁谐振现象进行分析,探讨... 升压变铁心存在剩磁时进行充电操作,在励磁涌流和操作电压波动的激励作用下,可能会引发铁磁谐振,对升压变及其相连的电压互感器产生不利影响,降低厂站设备的供电可靠性。本文对某电站升压变充电过程中产生的铁磁谐振现象进行分析,探讨了引发铁磁谐振的可能原因,并提出了避免铁磁谐振产生的应对策略。 展开更多
关键词 升压变 电压互感器 铁磁谐振 剩磁 励磁涌流
在线阅读 下载PDF
升压变电站智能巡检中的动态数据融合与异常检测方法
16
作者 张艺 《国外电子测量技术》 2026年第1期120-126,共7页
在变电站巡检中,由于设备类型多样、运行工况复杂,且长期处于高电压、大电流环境中,其运行状态的监测高度依赖多传感器系统。然而,传统多传感器数据融合方法多采用预设值加权,未考虑各传感器数据间的动态关联性,导致信息互补性不足,降... 在变电站巡检中,由于设备类型多样、运行工况复杂,且长期处于高电压、大电流环境中,其运行状态的监测高度依赖多传感器系统。然而,传统多传感器数据融合方法多采用预设值加权,未考虑各传感器数据间的动态关联性,导致信息互补性不足,降低了监测系统的可信度。为此,提出一种升压变电站智能巡检系统中的动态数据融合与异常检测方法。首先,通过集成暂态电压、高频电流及光纤温度等多种传感器,构建了智能巡检系统,采集变电站内部设备的电压、电流及温度等关键参数。在此基础上,引入基于距离熵的多传感器数据融合算法,动态分配不同传感器数据的权重,挖掘数据间的空间关联性,实现多源信息的有效互补与协同;随后,引入差分序列方差算法实现异常状态的自动精准检测。实验结果表明,所设计的多种传感器可以有效检测到变电站内各个设备的电流、电压等多种数据,结合其计算出的差分方差,检测到变电站节点中的异常缺陷数据,且检测过程中信息融合时延均小于1.1 s,信息传输能耗均小于36 J,证明该系统可以高效检测变电站中异常数据,具备较高的检测动态性。 展开更多
关键词 升压变电站 智能巡检 多传感器 数据融合 距离熵
原文传递
5G赋能下的风电场升压站全链条智慧运维应用方案研究
17
作者 张学强 《通信电源技术》 2026年第4期197-199,共3页
为解决风电场升压站通信覆盖不足、传输低效、存在安全隐患及运维滞后等问题,从覆盖、传输、安全、运维出发,利用5G设计相应的全链条智慧运维应用方案。该应用方案通过高低频协同专网、边缘计算+业务调度、双重安全防护及智慧运维融合,... 为解决风电场升压站通信覆盖不足、传输低效、存在安全隐患及运维滞后等问题,从覆盖、传输、安全、运维出发,利用5G设计相应的全链条智慧运维应用方案。该应用方案通过高低频协同专网、边缘计算+业务调度、双重安全防护及智慧运维融合,实现全链条技术适配。实验表明,该方案使室外与塔筒内信号强度、控制指令时延、视频回传速率等关键指标显著优于传统方案,攻击防护成功率达98.71%,故障排查时长缩短63.1%,能够为电力行业5G规模化应用提供实操范式,具有重要工程价值。 展开更多
关键词 5G 风电场升压站 通信 智慧运维
在线阅读 下载PDF
35 kV直升500 kV升压系统暂态稳定特性分析
18
作者 张滨 庞博 +1 位作者 黄德刚 伦季才 《中阿科技论坛(中英文)》 2026年第3期58-62,共5页
针对35 kV直升500 kV升压系统在故障扰动下的暂态稳定问题,文章建立了包含发电机、升压变压器、输电线路及励磁控制的电磁暂态仿真模型,结合典型工况与边界条件,在PSCAD/EMTDC平台开展稳态运行、轻度扰动、单相接地及三相短路故障仿真... 针对35 kV直升500 kV升压系统在故障扰动下的暂态稳定问题,文章建立了包含发电机、升压变压器、输电线路及励磁控制的电磁暂态仿真模型,结合典型工况与边界条件,在PSCAD/EMTDC平台开展稳态运行、轻度扰动、单相接地及三相短路故障仿真。研究结果表明,系统暂态稳定裕度主要受故障持续时间与励磁增益影响,当故障清除时间超过0.10 s或励磁增益偏低时,功角将快速发散导致系统失稳;提高励磁增益可有效增强电压支撑能力、延长暂态稳定时间,但励磁增益过大会引发动态过冲。经综合分析,励磁增益取250为最优区间。文章揭示了高压升压系统暂态稳定边界的关键影响因素,可为同类工程的励磁控制参数整定与稳定性优化提供参考依据。 展开更多
关键词 升压系统 暂态稳定 功角动态 励磁控制 电磁仿真
在线阅读 下载PDF
储能系统并网点过电压及绝缘特性分析
19
作者 郑毅 吴继平 +2 位作者 张科乾 黄小成 葛彬欣 《电气技术》 2026年第1期42-48,共7页
储能系统的调节作用受多方面因素的影响,除系统约束条件、选址定容等因素外,储能系统自身的可靠性也很关键。为保证储能系统在参与电压调节过程中能够可靠运行并提供有效的功率支撑,针对储能系统连接变压器出现的绝缘损坏问题,本文分析... 储能系统的调节作用受多方面因素的影响,除系统约束条件、选址定容等因素外,储能系统自身的可靠性也很关键。为保证储能系统在参与电压调节过程中能够可靠运行并提供有效的功率支撑,针对储能系统连接变压器出现的绝缘损坏问题,本文分析储能系统并网点的电压波动特性,并基于改进的IEEE 14节点系统开展详细计算。根据储能系统并网点因光伏出力变化、电池充放电、系统故障、操作冲击引起的实际过电压情况,提出储能系统连接变压器绝缘配置方法。储能系统连接变压器绝缘性能不能仅按照额定状态确定,应根据并网点实际过电压情况进行选择,以确保变压器能够适应所有运行工况。 展开更多
关键词 储能系统(ESS) 并网点 连接变压器 过电压 绝缘特性
在线阅读 下载PDF
基于改进YOLOv5算法的电力升压变电站设备智能巡检方法
20
作者 穆红艳 《自动化应用》 2026年第4期45-47,51,共4页
针对西藏贡觉拉妥升压变电站高海拔、低温、强风等复杂环境下的设备故障检测需求,提出了一种基于改进YOLOv5(I-YOLOv5)的智能巡检方法。该方法通过扩展检测尺度至4个、引入双向特征金字塔网络(Bi-FPN)优化特征融合、在C3模块中融入挤压... 针对西藏贡觉拉妥升压变电站高海拔、低温、强风等复杂环境下的设备故障检测需求,提出了一种基于改进YOLOv5(I-YOLOv5)的智能巡检方法。该方法通过扩展检测尺度至4个、引入双向特征金字塔网络(Bi-FPN)优化特征融合、在C3模块中融入挤压-激励(SE)网络,强化对小目标设备的识别能力与复杂环境适应性。实验结果显示,I-YOLOv5的精确率、召回率、mAP@0.5分别达到96.79%,95.07%,96.44%,较原始YOLOv5s提升3.45%,3.86%,3.51%,且优于主流升级模型YOLOv8s。最终将I-YOLOv5模型部署到各个终端上,构建了集摄像机定点监测、无人机动态巡检、工业电视宏观监控于一体的智能化巡检系统,实现了设备异常自动检测与告警,全方位保障了变电站运行,为智能化运维提供了有力技术保障。 展开更多
关键词 I-YOLOv5算法 升压变电站 高原电力设备 智能巡检
在线阅读 下载PDF
上一页 1 2 34 下一页 到第
使用帮助 返回顶部