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The Design and Implementation of a Biomechanics-Driven Structural Safety Monitoring System for Offshore Wind Power Step-Up Stations
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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
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Research on the Selection and Layout Scheme of Main Transformers in the Primary Electrical Design of New Energy Step-Up Stations
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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
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一种低输入电压、低功率Step-up DC-DC变换器的设计
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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
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One-step laparoscopic pancreatic necrosectomy verse surgical step-up approach for infected pancreatic necrosis:a case-control study 被引量:13
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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
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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
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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
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Controversies in the treatment of Crohn’s disease: The case for an accelerated step-up treatment approach 被引量:4
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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
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Comparison Analysis of Efficiency Between Double-Synchronous Step-Down-Stress and Step-Up-Stress Accelerated Life Tests 被引量:1
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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
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Fuzzy Based Interleaved Step-up Converter for Electric Vehicle
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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
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Step-up approach in emphysematous hepatitis: A case report
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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
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Analysis and Design of Single Switch Hybrid Step-Up Converter
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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
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带倍压单元的有源开关电感高增益变换器及其磁集成
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作者 李洪珠 陈星星 +2 位作者 李超 包雨林 李洪亮 《电工技术学报》 北大核心 2025年第7期2191-2202,共12页
有源开关电感结构将两条支路并联,可以降低开关管电流应力,实现高效的能量转换。然而,两个有源开关的交错导通会导致控制电路变得复杂。此外,仅采用有源开关电感结构可能无法达到足够的电压增益。为了解决这些问题,该文提出带倍压单元... 有源开关电感结构将两条支路并联,可以降低开关管电流应力,实现高效的能量转换。然而,两个有源开关的交错导通会导致控制电路变得复杂。此外,仅采用有源开关电感结构可能无法达到足够的电压增益。为了解决这些问题,该文提出带倍压单元的有源开关电感高增益变换器结构。通过引入耦合电感和开关电容单元,提高电压增益。两个开关管同时开断的设计降低了控制电路的复杂度和成本。耦合电感的设计采用EIE型磁心,通过仿真和实验验证,实现两个耦合电感的解耦集成。最后,通过搭建一台输入电压为24V、输出电压为400V、满载功率为360W的实验样机,验证了所提变换器的合理性。 展开更多
关键词 有源开关电感 耦合电感 开关电容 高增益 磁集成
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弥漫性分布感染性坏死性胰腺炎的个体化干预策略:微创阶梯式与直接开腹手术的疗效比较
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作者 李志强 瞿吉浩然 +3 位作者 涂广平 陈浪 余枭 刘云飞 《中国普通外科杂志》 北大核心 2025年第9期1909-1922,共14页
背景与目的:感染性坏死性胰腺炎(INP)尤其是弥漫性分布者病情凶险。对于首选干预策略(微创阶梯式vs.直接开腹坏死清除术)仍存在争议;此外“湿性”与“干性”坏死,以及是否合并重症急性胰腺炎(SAP)对策略选择的影响尚不明确。本研究旨在... 背景与目的:感染性坏死性胰腺炎(INP)尤其是弥漫性分布者病情凶险。对于首选干预策略(微创阶梯式vs.直接开腹坏死清除术)仍存在争议;此外“湿性”与“干性”坏死,以及是否合并重症急性胰腺炎(SAP)对策略选择的影响尚不明确。本研究旨在比较两种策略在弥漫性分布INP中的疗效与安全性,并评估基于CT影像的坏死类型与SAP状态在决策中的指导价值。方法:回顾性分析2012年1月—2023年3月中南大学湘雅三医院收治的458例弥漫分布INP患者,其中微创阶梯式组256例,直接开腹组202例。按基于决定因素的分类法定义SAP,依据CT特征将坏死分为“湿性”和“干性”。比较两组主要终点事件(死亡或严重并发症复合终点)及次要终点事件(死亡率、住院时间、切口并发症等),并进行亚组分析。结果:总体上,直接开腹组主要终点事件发生率(62.4%vs.48.1%,P=0.003)及死亡率(27.2%vs.16.8%,P=0.008)均高于微创阶梯式组。SAP亚组中,阶梯式治疗主要终点事件发生率更低(66.7%vs.97.7%,P=0.003)。非SAP患者中,两组主要终点事件发生率相近,但直接开腹组住院时间更短[(36.5±10.4)d vs.(45.6±18.6)d,P<0.001],切口感染和切口疝更常见(均P<0.001)。多因素分析显示,感染出现时间、积液特征、气泡征及坏死部位为阶梯式治疗长期住院的独立预测因素(均P<0.05)。“湿性”坏死患者经微创阶梯式治疗获益更大,而“干性”坏死患者经直接开腹治疗住院时间更短。结论:对于弥漫性分布的INP,治疗策略应基于SAP状态与坏死液化/影像特征个体化选择:阶梯式微创优先适用于SAP患者及CT示“湿性”坏死者;对于“干性”坏死(尤其液化不充分者),直接开腹清创在缩短住院时间与降低某些主要终点事件方面更具优势,但需警惕切口感染与切口疝等并发症。CT影像学特征与SAP分类可作为风险分层工具,指导个体化干预时机与方式。 展开更多
关键词 胰腺炎 急性坏死性 阶梯式疗法 剖腹术 治疗结果
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双耦合电感磁集成开关电容二次型高增益变换器
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作者 李洪珠 包雨林 +2 位作者 李超 陈星星 李洪亮 《电工技术学报》 北大核心 2025年第12期3964-3976,共13页
为进一步提高非隔离DC-DC变换器的高增益性,降低开关管的电压应力,提出一种双耦合电感磁集成开关电容二次型高增益变换器,采用单个开关管降低了拓扑结构的复杂度,引入两对耦合电感可以较大程度地提升变换器的高增益性、降低开关管两端... 为进一步提高非隔离DC-DC变换器的高增益性,降低开关管的电压应力,提出一种双耦合电感磁集成开关电容二次型高增益变换器,采用单个开关管降低了拓扑结构的复杂度,引入两对耦合电感可以较大程度地提升变换器的高增益性、降低开关管两端的电压应力,使用钳位结构可以吸收漏感能量再利用,可以有效缓解电压尖峰。该变换器引入磁集成技术将两对耦合电感进行解耦集成可进一步减小变换器磁件的体积和数量。该文分析变换器的主要工作波形与原理,在此基础上推导变换器的各项参数,对解耦集成磁件进行结构与参数设计并进行仿真验证,最后通过一台输入12 V、输出185 V、额定功率200 W的实验样机,验证了理论分析的正确性。 展开更多
关键词 二次型高增益变换器 开关电容 磁集成 耦合电感
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110 kV变电站配电装置技术改造研究
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作者 卢英欣 《现代工程科技》 2025年第7期113-116,共4页
随着上海地区电网提标改造推进,将逐步淘汰老旧35 kV变电站及可靠性较差35 kV线路,发电厂原有的35 kV上网线路即将退出运行。为了解决此问题,对发电厂原有的变电站进行增容和线路改造,既能满足3台发电机满负荷上网的容量要求,又能提高... 随着上海地区电网提标改造推进,将逐步淘汰老旧35 kV变电站及可靠性较差35 kV线路,发电厂原有的35 kV上网线路即将退出运行。为了解决此问题,对发电厂原有的变电站进行增容和线路改造,既能满足3台发电机满负荷上网的容量要求,又能提高发电厂上网线路的可靠性、稳定性。以某发电厂内升压站改造为例,分别对一次系统设计、保护配置、设备选型等改造项目提出更优的解决方案。通过改造,将厂内3台发电机组通过二期110 kV升压变汇聚后,统一由110 kV线路接入电网,保证了2回35 kV线路停役后,厂内所有发电机组均能正常运行。 展开更多
关键词 power plant step-up substation primary system protection device technical transformation
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基于弹性变换法的非线性微分方程可解类分析
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作者 丁李 《佳木斯大学学报(自然科学版)》 2025年第7期177-180,共4页
微分方程是数学的重要分支,但现有方法只能对少数非线性微分方程进行求解。因此,研究提出了采用弹性理论的非线性微分方程求解方法,通过弹性变换法,非线性微分方程可转换为线性微分方程,再逆向进行求解。举例论证表明,弹性变换法能够将... 微分方程是数学的重要分支,但现有方法只能对少数非线性微分方程进行求解。因此,研究提出了采用弹性理论的非线性微分方程求解方法,通过弹性变换法,非线性微分方程可转换为线性微分方程,再逆向进行求解。举例论证表明,弹性变换法能够将高阶或低阶非线性微分方程进行降阶或升阶处理,将其转换为能够求出通解的线性微分方程,最终求出非线性微分方程的通解。由此可得,弹性变换法能够有效提升微分方程的可解类,为解决各领域的实际问题寻找初值条件提供了铺垫。 展开更多
关键词 弹性变换 微分方程 弹性升阶 弹性降阶 可解类
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面向海上风电直流升压汇集的非对称双向有源桥DC-DC变换器 被引量:3
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作者 肖寒冰 马建军 +2 位作者 朱淼 文书礼 孔祥平 《中国电机工程学报》 北大核心 2025年第7期2719-2731,I0023,共14页
为满足海上风电直流升压汇集需求,提出一种具备非对称双向功率传输能力的DC-DC变换器方案。在海上风电功率正向外送时,能够实现并联输入串联输出升压功能。在风电场需要功率反向支撑时,通过改变变换器调制策略,能够实现较小功率容量下... 为满足海上风电直流升压汇集需求,提出一种具备非对称双向功率传输能力的DC-DC变换器方案。在海上风电功率正向外送时,能够实现并联输入串联输出升压功能。在风电场需要功率反向支撑时,通过改变变换器调制策略,能够实现较小功率容量下反向功率传输。首先分析正/反向模态下,变换器零电压开关(zero voltage switching,ZVS)软开关与功率传输特性。在此基础上,同时考虑输出电压调节与串联电压均衡多运行目标,构建相应调制与控制策略。与传统双向变换器相比,所提拓扑在满足非对称双向功率变换需求的同时,通过降低元件数量,能够降低变换器成本。基于仿真与实验结果,对所提出非对称双向变换器功率调节、模式切换与软开关特性进行测试,验证所提非对称双向变换器概念与方案的有效性。 展开更多
关键词 直流风电升压汇集 非对称双向功率变换 多模式运行 软开关运行 均压控制
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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:22
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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
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用于光伏发电的新型双极性输出DC-DC变换器
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作者 邹启衡 李洁 +3 位作者 钱科军 朱庆 徐煦 石家铮 《电测与仪表》 北大核心 2025年第4期217-224,共8页
提出一种用于光伏发电系统前端功率变换的新型双极性输出直流-直流(direct current-direct current, DC-DC)变换器。根据电路拓扑优化组合的创新思路,该变换器融合了Zeta变换器和Buck-Boost变换器的拓扑结构,输入端共用一颗开关器件和... 提出一种用于光伏发电系统前端功率变换的新型双极性输出直流-直流(direct current-direct current, DC-DC)变换器。根据电路拓扑优化组合的创新思路,该变换器融合了Zeta变换器和Buck-Boost变换器的拓扑结构,输入端共用一颗开关器件和一颗功率电感,正极性输出端采用Zeta变换器的输出侧电路结构,负极性输出端采用Buck-Boost变换器的输出侧电路结构。推演了该新型变换器拓扑的由来,并分析其在电感电流连续模式下的工作模态。对该变换器的电压增益、器件应力等稳态特性进行推导,并对主要器件进行参数设计和选型。基于PSIM软件进行仿真分析,所得仿真波形符合理论分析结果。研制了一台功率为1 kW,峰值效率为94.5%的硬件样机,实测样机工作波形与理论分析和仿真结果一致。研究结果表明该变换器具有结构简单、双极性输出、升降压、效率较高和适合于光伏发电应用的特点。 展开更多
关键词 DC-DC变换器 双极性输出 升降压 光伏发电
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浮空器电源电流均衡非谐振线性软开关直流升压变换拓扑
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作者 胡肖飞 李虹 +2 位作者 曾洋斌 苏文哲 徐国宁 《北京航空航天大学学报》 北大核心 2025年第8期2792-2800,共9页
临近空间浮空器在通信保障、地质勘探、科学实验等领域得到广泛应用,其电能变换设备因特殊的应用场景,要求具有高效、小型化和轻量化特征,又因浮空器电源中光伏电池的输出侧端口电压较低,直流母线电压较高,研制高效率、高功率密度和高... 临近空间浮空器在通信保障、地质勘探、科学实验等领域得到广泛应用,其电能变换设备因特殊的应用场景,要求具有高效、小型化和轻量化特征,又因浮空器电源中光伏电池的输出侧端口电压较低,直流母线电压较高,研制高效率、高功率密度和高电压增益的直流变换器对临近空间浮空器电源至关重要。在此技术背景下,基于可以实现高增益的箝位电容变换器和非谐振软开关技术,提出一种新型电流均衡非谐振线性(NRL)软开关直流升压变换拓扑。所提拓扑能够实现所有开关管的零电流(ZCS)开通和所有二极管的ZCS关断,同时能够消除因电容充放电导致的器件电流尖峰。通过仿真和硬件试验验证了所提拓扑的有效性和正确性,为临近空间浮空器电源中直流升压电能变换提供了一种新的拓扑选择。 展开更多
关键词 浮空器电源 直流升压变换器 非谐振线性软开关技术 高增益 拓扑
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1000kV、265/450MVA核电特高压升压变压器设计方案的探讨及论证
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作者 张智勇 林文生 盈文亮 《变压器》 2025年第11期13-19,共7页
本文作者简要探讨了1000kV核电特高压升压变压器的主要技术参数和关键技术,旨在为核电领域提供更加可靠、高效的特高压升压变压器解决方案。
关键词 升压变压器 核电 特高压
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