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Heyan Kuntai capsule versus dehydroepiandrosterone in treating Chinese patients with infertility caused by diminished ovarian reserve: a multicenter, randomized controlled trial 被引量:17
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作者 Gao Hui Xia Tian +8 位作者 Ma Ruihong Zhao Zhimei Song Xueru Wang Baojuan Liu Lijing Han Kaimei Wang Guoqing Fu Yu Hao Guimin 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2017年第4期530-537,共8页
OBJECTIVE: To evaluate the clinical efficacy and safety of Heyan Kuntai capsule(HYKT) in treating women with infertility caused by diminished ovarian reserve(DOR).METHODS: One hundred eight eligible patientsfrom three... OBJECTIVE: To evaluate the clinical efficacy and safety of Heyan Kuntai capsule(HYKT) in treating women with infertility caused by diminished ovarian reserve(DOR).METHODS: One hundred eight eligible patientsfrom three Chinese hospitals were randomly divided into an HYKT treatment group(n = 55) or a dehydroepiandrosterone(DHEA) treatment group(n =53). Patients in the HYKT group were treated orally with four 0.5 g HYKT three times a day; patients in the DHEA group were treated with one 25.0 mg DHEA capsule three times a day. All patients were treated for 3 months and followed up over a3-month period.RESULTS: Of 108 patients, 12 dropped out: six from the HYKT group, and six from the DHEA group. Eleven patients got pregnant during the treatment. Serum anti-Müllerian hormone levels and antral follicle counts increased significantly in both groups after treatment(P < 0.05) especially in the HYKT group(P < 0.05). Serum follicle stimulating hormone(FSH) levels and FSH/luteinizing hormone ratios decreased(P < 0.05) with no significant difference between the two groups. Estradiol levels in the HYKT group and DHEA-sulfate levels in the DHEA group both increased(P < 0.05). The spontaneous pregnancy rates were 12% and 11% in the HYKT and DHEA groups, respectively(not significant). During the follow-up period, 16 patients in the HYKT group underwent in vitro fertilization-embryo transfer(IVF-ET) and the number of retrieved oocytes was(5.1 ± 1.8). In DHEA group, 20 patients underwent IVF-ET and the number of retrieved oocyte was(4.2 ± 1.9)(not significant); clinical pregnancy rates were 38% in the HYKT group and 20%in DHEA group(not significant). No significant adverse reactions were observed.CONCLUSION: HYKT can improve the ovarian re-serve and hormone levels in patients with infertility caused by DOR. Pregnancy rates after HYKT treatment were similar to those of DHEA treatment.HYKT might be an alternative to the treatment of infertility caused by DOR. 展开更多
关键词 Infertility female Ovarian reserve HORMONES DEHYDROEPIANDROSTERONE Heyan Kuntai capsule Randomized controlled trial
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Effectiveness of tonifying-kidney and regulating-liver therapy on diminished ovarian reserve: a systematic review and Meta-analysis of randomized controlled trials 被引量:8
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作者 Liu Liuqing Liu Yanfeng +5 位作者 Yang Ming Xu Guiqin Li Ruiqi Xu Xiuli Pan Xue Liang Jialing 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2020年第3期343-354,共12页
OBJECTIVE: To evaluate the effectiveness of the Traditional Chinese Medicine tonifying-kidney and regulating-liver therapy on diminished ovarian reserve(DOR).METHODS: The literature was comprehensively searched up to ... OBJECTIVE: To evaluate the effectiveness of the Traditional Chinese Medicine tonifying-kidney and regulating-liver therapy on diminished ovarian reserve(DOR).METHODS: The literature was comprehensively searched up to August 2019 using four Chinese and three English electronic databases to extract randomized clinical trials(RCTs) comparing Traditional Chinese Medicine tonifying-kidney and regulating-liver prescriptions(combined with hormone therapy or not) with Western Medicine. Data quality evaluation was conducted using the Cochrane risk of bias tool. Meta-analysis was conducted using Revman 5.3 software with effect estimates presented as mean difference(MD), risk ratio(RR), and95% confidence interval(CI).RESULTS: A total of nine RCTs with 512 participants were extracted and eligible for Meta-analysis.There were no significant differences between Chinese medicine and Western Medicine on basal serum follicle-stimulating hormone(FSH) level(MD0.11, 95% CI-0.52 to 0.74, 392 participants, seven trials), anti-Müllerian hormone level(MD 0.48, 95%CI-0.62 to 1.58, 95 participants, two trials), and the FSH and luteinizing hormone ratio(MD 0.01,95% CI-0.95 to 0.96, 115 participants, two trials).Chinese medicine was more effective at improving Traditional Chinese Medicine symptom scores(TCMSS)(MD-2.39, 95% CI-3.83 to-0.94, 160 participants, three trials), effective rate of TCMSS(RR1.18, 95% CI 1.02 to 1.36, 160 participants, three trials), antral follicle count(AFC)(MD 0.55, 95% CI 0.05 to 1.04, 155 participants, three trials), and FSH levels at 3 months post-treatment(MD-4.77, 95% CI-6.09 to-3.45, 137 participants, two trials).CONCLUSION: Compared with Western Medicine,tonifying-kidney and regulating-liver therapy is more effective at relieving symptoms and improving AFC and FSH at 3 months post-treatment. 展开更多
关键词 Ovarian reserve Tonifying kidney and regulating liver Randomized controlled trial Systematic review META-ANALYSIS
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Protection and Quality Control of Wild Chinese Herbal Medicine Resources in Nature Reserves by Taking Longyuwan Scenic Spot Within Funiu Mountain Nature Reserve as an Example 被引量:1
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作者 Wang Shao-hui Liu Meng-na +4 位作者 Wang Xu Zhang Ya-chen Han Yi-wen Zhang Ce Liu Tong-xiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期90-96,共7页
This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Thr... This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Through the combination of three methods including literature review, visiting and investigational studies, and field surveys, the data of investigation, collection and collation were analyzed. According to data of surveys, collection and collation, problems related to the protection of wild Chinese herbal medicine resources faced by Longyuwan Scenic Spot within Funiu Mountain Nature Reserve were also analyzed and protection strategies and quality control of wild Chinese herbal medicine resources in this nature reserve were discussed. It was expected that the results would provide important scientific references for the sustainable development, protection and quality control of wild Chinese herbal medicine resources within nature reserves. 展开更多
关键词 nature reserve wild Chinese herbal medicine resource PROTECTION quality control
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Effectiveness of Firewise Approach(FWA)in Controlling Forest Fire:A Case of Uluguru Nature Forest Reserve(UNFR),Morogoro,Tanzania
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作者 Pilly Joseph Kagosi Siwa Ernest Nkya +1 位作者 Chelestino Peter Balama Innocent Hamisi Babili 《Journal of Agricultural Science and Technology(B)》 2020年第3期175-185,共11页
Forest fire has received considerable attention in literature because it is considered one of the most common factors causing disturbances in ecosystems and at the same time considered vital in maintaining ecosystems.... Forest fire has received considerable attention in literature because it is considered one of the most common factors causing disturbances in ecosystems and at the same time considered vital in maintaining ecosystems.Firewise Approach(FWA)has been proposed and used for controlling forest fire and achieving sustainable forest management.The approach requires involvement of communities in managing forest fire incidences in reserved forests.Despite considerable period since FWA has been practiced,there is insufficient scholarly knowledge on effectiveness of the approach in managing forest fire.This paper examines the effectiveness of FWA in managing forest fires in Uluguru Nature Forest Reserve(UNFR).The study employed cross-section research design that involved quantitative and qualitative data collection.The data were analysed using Statistical Package for Social Science(SPSS)software and content analysis.The study found alternating periods:the period of overall decrease of wildfire incidences within initial five years of practising the approach.The study concludes that the FWA is useful in reducing forest fire incidences during early period of practising the approach and another period of huge fire occurrence beyond five years.However,the FWA has challenges of sustaining successes in controlling forest fires including limited fire management training to common community.The study recommends sustaining communities’trainings on forest fire management. 展开更多
关键词 Effectiveness of firewise approach controlling forest fire Uluguru Nature Forest reserve.
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The “fracture-controlled reserves” based stimulation technology for unconventional oil and gas reservoirs 被引量:4
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作者 LEI Qun YANG Lifeng +5 位作者 DUAN Yaoyao WENG Dingwei WANG Xin GUAN Baoshan WANG Zhen GUO Ying 《Petroleum Exploration and Development》 2018年第4期770-778,共9页
To solve the problems facing the economic development of unconventional oil and gas, a new concept and corresponding technology system of reservoir stimulation based on "fracture-controlled reserves" are put... To solve the problems facing the economic development of unconventional oil and gas, a new concept and corresponding technology system of reservoir stimulation based on "fracture-controlled reserves" are put forward. The "fracture-controlled reserves" stimulation technology is to realize the three-dimensional producing and economic and efficient development of unconventional hydrocarbon resources by forming a fracture system that well matches "sweet spots" and "non-sweet spots". The technical route of the stimulation technology is "three optimizations and controls", that is, control the scope of sand body through optimizing well spacing, control the recoverable reserves through optimizing fracture system, and control the single well production reduction through optimizing energy complement method. The "fracture-controlled reserves" stimulation emphasizes the maximization of the initial stimulation coefficient, the integration of energy replenishment, stimulation and production, and prolonging the re-fracturing cycle or avoiding re-fracturing. It aims at realizing the three-dimensional full producing and efficient development of reservoir in vertical and horizontal directions and achieving the large-scale, sustainable and high profitable development of unconventional oil and gas resources. The stimulation technology was used to perform 20 pilot projects in five typical tight-oil, shale gas blocks in China. The fracturing and producing effects of tight oil improved and the commercial development for shale gas was realized. 展开更多
关键词 unconventional OIL and GAS tight OIL and GAS shale OIL and GAS fracture-controlled reserveS initial STIMULATION coefficient FRACTURE parameters OPTIMIZATION well pattern OPTIMIZATION energy complement
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Reservation-based dynamic admission control scheme for wideband code division multiple access systems
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作者 A.Y.Al-nahari S.A.El-Dolil +1 位作者 M.I.Dessouky F.E.Abd El-Samie 《Journal of Central South University》 SCIE EI CAS 2012年第2期393-401,共9页
Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very sca... Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very scarce resource as the radio spectrum. A new scheme was proposed which extends the concepts of resource sharing and reservations for wideband code division multiple access (WCDMA) systems with a unique feature of soft capacity. Voice and data traffic were considered. The traffic is further classified into handoff and new requests. The reservation thresholds were dynamically adjusted according to the traffic pattern and mobility prediction in order to achieve the maximum channel utilization, while guaranteeing different QoS constraints. The performance of proposed scheme was evaluated using Markov models. New call blocking probability, handoff call dropping probability, and channel utilization were used as benchmarks for the proposed scheme. 展开更多
关键词 admission control resource reservation wideband code division multiple access resource utilization
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森林储量遥感估测的不确定性研究进展
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作者 孙华 龙依 +2 位作者 王储 郑欢娜 高佳乐 《中南林业科技大学学报》 北大核心 2026年第2期1-12,共12页
森林“三储量”,即森林蓄积量、生物量和碳储量,是各级森林资源监测的重要指标,也是反映森林生态系统质量和生产力的重要参数。森林储量遥感估测并非直接测量过程,而是依赖于遥感变量与地面森林储量之间建立的映射模型,往往涉及许多误... 森林“三储量”,即森林蓄积量、生物量和碳储量,是各级森林资源监测的重要指标,也是反映森林生态系统质量和生产力的重要参数。森林储量遥感估测并非直接测量过程,而是依赖于遥感变量与地面森林储量之间建立的映射模型,往往涉及许多误差和不确定性来源,包括采样限制与测量误差、传感器噪声和分辨率限制、大气条件变化、模型选择和参数估计的不确定性等。系统性地识别、量化并控制这些误差,对于提升森林储量遥感估测的准确性和可靠性具有重要价值。因此,本研究从森林储量样本、遥感估测数据源和遥感估测模型三方面出发,分析森林储量遥感估测中的不确定性,并对森林储量估测中的不确定性度量与误差控制方法进行探讨。本研究有助于深入理解森林储量遥感估测中的不确定性来源,可为进一步提升森林储量估测精度、优化森林资源监测与管理措施提供参考。 展开更多
关键词 森林储量 遥感估测 不确定性来源 误差控制 度量方法
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强非均质性气藏压裂水平井分段产量劈分新方法——以鄂尔多斯盆地东胜气田二叠系盒1段气藏为例
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作者 荀小全 李宏涛 +2 位作者 李长平 杨帆 刘雄 《岩性油气藏》 北大核心 2026年第1期191-200,共10页
为了定量评价强非均质性气藏压裂水平井各压裂段初期产气量的贡献率,以鄂尔多斯盆地东胜气田新召气区二叠系盒1段气藏为例,基于储层地质工程参数、压裂缝特征、产气剖面测试分析,提出了综合地质工程因素的“缝控储量”的分段产量劈分新... 为了定量评价强非均质性气藏压裂水平井各压裂段初期产气量的贡献率,以鄂尔多斯盆地东胜气田新召气区二叠系盒1段气藏为例,基于储层地质工程参数、压裂缝特征、产气剖面测试分析,提出了综合地质工程因素的“缝控储量”的分段产量劈分新方法。研究结果表明:(1)东胜气田新召气区二叠系盒1段气藏压裂缝特征受到地质和工程双重因素控制,相同施工参数下,物性越好,压裂缝半长越短;相同地质条件下,施工排量越大、入地净液量越大,压裂缝半长越长,射孔簇数越多,压裂缝半长越短;同一区域,不同类型储层压裂缝半长与波及宽度比一致。(2)水平段各压裂段产出明显受到地质工程因素影响,物性好、含气性好、压裂施工规模大,压裂后产能越高。(3)综合考虑地质工程因素,明确改造的“缝控储量”与强非均质性气藏水平井各压裂段初期产能呈线性关系,相关系数达到0.997,表现为缝控储量高,各压裂段产能占比高。通过“缝控储量”劈分方法与产气剖面测试结果对比发现,Ⅰ类、Ⅱ类储层各段劈分产气量相对误差在12%以内。 展开更多
关键词 强非均质性气藏 压裂缝 产气剖面 缝控储量 产量劈分 盒1段 二叠系 东胜气田 鄂尔多斯盆地
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油藏水驱后注天然气驱动态分析通用图版建立
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作者 熊钰 李亚梅 +3 位作者 孙泽威 母丹 耿文爽 袁立新 《石油与天然气地质》 北大核心 2026年第2期638-653,共16页
水驱动态分析广泛应用童氏图版,但注气动态分析中却缺乏类似的通用图版,导致工程应用中难以判断气驱动态和措施有效性。基于二维实验建立了水驱后气驱通用特征曲线关系式及水驱后气驱通用图版,提出了针对具体油藏建立通用图版的方法和... 水驱动态分析广泛应用童氏图版,但注气动态分析中却缺乏类似的通用图版,导致工程应用中难以判断气驱动态和措施有效性。基于二维实验建立了水驱后气驱通用特征曲线关系式及水驱后气驱通用图版,提出了针对具体油藏建立通用图版的方法和步骤。研究认为:(1)提出的水转气驱合理停注时机确定方法、利用停注气/油比确定理论图版常数方法和针对具体油藏不同注气方式时常系数(b^(-))确定方法,实例应用分析显示该方法科学合理。(2)采用所提出的图版常数确定法,对塔里木油田东河区块CⅢ1层段气驱控制储量预测的误差约为6%。(3)应用所建立的水驱转天然气驱通用图版,对强非均质性的X油田4油组进行评价,预测其水驱后顶部注天然气重力辅助驱的最终采收率。其结果与长岩心实验结果及数值模拟分析结果一致,表明利用基于理论图版敏感性所给出水驱转气驱主要控制因素,并与该通用图版结合,可有效分析注气动态、提升注气效果。(4)在塔里木油田东河区块CⅢ1层段顶部注气辅助混相驱和X油田4油组顶部注气非混相驱两类注天然气驱替油藏实际应用并开展预测,均取得较好效果,表明所提出方法对不同类型的水驱后气驱开发油藏具有较好的通用性。 展开更多
关键词 采收率标定 气驱控制储量 注气稳定性判别 气驱动态图版 非均质性 高倾角油藏 油田开发
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中国页岩气典型区块开发规律与分析
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作者 王纪伟 康玉柱 +3 位作者 魏海鹏 李东晖 宋丽阳 高安荣 《断块油气田》 北大核心 2026年第2期177-183,共7页
页岩气作为清洁能源,已成为全球“双碳”目标下最现实的过渡资源,但中国针对页岩气的勘探开发工作尚处于早期,储量动用规律、开发生产规律、产能主控因素等不明确。文中以中国石化6个已开发区块为例,基于各区块实际开发过程中取得的地... 页岩气作为清洁能源,已成为全球“双碳”目标下最现实的过渡资源,但中国针对页岩气的勘探开发工作尚处于早期,储量动用规律、开发生产规律、产能主控因素等不明确。文中以中国石化6个已开发区块为例,基于各区块实际开发过程中取得的地质、工程、采气等资料,系统对比分析其储量动用模式、区块开发模式及开发指标等。研究结果表明:1)页岩气储量动用模式可分为快速高效动用、边评价边动用2类模式;气井初期递减快、后期低产递减趋缓,总体符合双曲+指数递减模型;2)6个典型区块开发模式可以分为快速建产、稳步建产2种模式,稳产期探明储量采气速度分别为1.50%,0.65%;3)明确了气藏储层压力、试气段长度、液量是影响页岩气井产能的主控因素,并基于13项指标建立了页岩气井产能预测模型,预测结果与实测无阻流量平均符合率为75.8%。该文成果可有效指导中国页岩气高效开发,且具有重要理论意义。 展开更多
关键词 页岩气 储量动用 产能 生产规律 主控因素 预测模型
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基于阻尼转矩法的变桨减载调频风电机组稳定性分析与参数稳定条件
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作者 奥博宇 景志滨 +2 位作者 李洪波 陈磊 闵勇 《电工技术学报》 北大核心 2026年第1期169-181,共13页
通过变桨减载预留备用容量是变速风电机组参与调频的一种重要技术方案,但参数设置不当时风电机组可能出现振荡甚至不稳定。该文首先通过变桨减载调频风电机组模型,对不合理风机参数下风电机组发生振荡的场景进行仿真。然后在该场景下分... 通过变桨减载预留备用容量是变速风电机组参与调频的一种重要技术方案,但参数设置不当时风电机组可能出现振荡甚至不稳定。该文首先通过变桨减载调频风电机组模型,对不合理风机参数下风电机组发生振荡的场景进行仿真。然后在该场景下分析变桨减载调频风电机组的稳定性,对机组动态方程进行线性化,基于阻尼转矩法分析了风电机组电磁功率、机械功率各部分的阻尼转矩及不同因素的影响,重点分析桨距角控制产生的阻尼转矩,得到参数不当时桨距角控制产生的负阻尼转矩是导致风电机组不稳定的主要原因。最后推导了具有解析表达式的参数稳定条件,当控制参数满足所提约束条件时,可以保证调频风电机组的稳定性。仿真结果验证了所提方法的有效性。 展开更多
关键词 风电机组 变桨减载调频 稳定性 桨距角控制器 阻尼转矩 参数稳定条件
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计及风机禁止转速区间的风-火协同两阶段随机备用优化
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作者 陈肖璐 郑博文 +2 位作者 窦宇宇 江博游 郭创新 《可再生能源》 北大核心 2026年第1期86-94,共9页
风电机组可通过超速控制提供备用容量,以提升电力系统运行经济性,但未充分考虑风电超速控制过程中风机危险运行区域。文章从感应发电机效应原理出发,推导出禁止转速区间,分析其对风电超速备用容量的影响,并建立了计及禁止转速区间的风... 风电机组可通过超速控制提供备用容量,以提升电力系统运行经济性,但未充分考虑风电超速控制过程中风机危险运行区域。文章从感应发电机效应原理出发,推导出禁止转速区间,分析其对风电超速备用容量的影响,并建立了计及禁止转速区间的风电备用模型。在此基础上,建立了计及禁止转速区间的风电-火电协同备用优化模型,并利用multi-cut Benders分解法进行求解。算例结果验证了风电提供备用能够提升系统频率稳定性和运行经济性,以及考虑禁止转速区间的必要性。 展开更多
关键词 风电机组 备用容量 超速控制 禁止转速区间 随机优化
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预防与紧急协调的电动汽车参与应急备用优化
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作者 吴巨爱 褚蕙 +2 位作者 薛禹胜 张腾飞 谢东亮 《电力系统自动化》 北大核心 2026年第5期85-97,共13页
随着电动汽车(EV)的大规模推广应用,EV集群作为一类潜力巨大的应急备用资源备受关注。目前,在EV集群参与应急备用的工程应用中,仍面临着车网互动场景不确定、EV备用耦合约束复杂、可信度低下、市场支撑机制匮乏等难题。为此,首先从“信... 随着电动汽车(EV)的大规模推广应用,EV集群作为一类潜力巨大的应急备用资源备受关注。目前,在EV集群参与应急备用的工程应用中,仍面临着车网互动场景不确定、EV备用耦合约束复杂、可信度低下、市场支撑机制匮乏等难题。为此,首先从“信息-物理-社会”维度提出了涵盖行为层、设备层和平台层的车网互动架构;然后,针对功率缺额事件的不确定性,设计了适用于不同功率缺额事件场景的市场规则,提出了日前预防性多场景风险优化与日内应急调控相协调的滚动优化决策流程;进一步,以聚合商收益最大为目标,构建了EV集群参与备用市场时预防与紧急协调的调度策略优化模型;最后,通过算例仿真与灵敏度分析,验证了不同市场规则的适应性与优化模型的有效性。在交互架构设计、市场规则设计和充放电策略优化方面,为EV集群参与应急备用提供了有效方案。 展开更多
关键词 基于能源的信息-物理-社会系统 电动汽车 应急备用 不确定性 市场规则 调度策略 预防控制 紧急控制
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煤层气井达标产量在开发调控中的应用
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作者 董文明 《煤炭技术》 2026年第1期136-140,共5页
煤层气主要以吸附态存在于煤基质中,需经历降压使气体解吸才能被采出。随着煤层压力变化,解吸速率也随之改变,需要不断调整产量来适应解吸过程,确保煤层气连续产出。现场调整一般采取经验法定性判断,缺少定量化依据。本文引入达标产量... 煤层气主要以吸附态存在于煤基质中,需经历降压使气体解吸才能被采出。随着煤层压力变化,解吸速率也随之改变,需要不断调整产量来适应解吸过程,确保煤层气连续产出。现场调整一般采取经验法定性判断,缺少定量化依据。本文引入达标产量作为煤层气井产量调控的重要参考指标。在充分认识M块煤层气井开发效果影响因素的基础上,运用单井控制储量与产量回归的方法较准确预测出达标产量,产量范围可控制在28%以内,实现由经验法摸索向定量化计算的转变,分开发阶段总结出适宜本块的提产模式,为后期投产的煤层气井合理提产计划提供重要参考。研究表明,提产过程遵循平稳、缓慢的原则,开发初期平均提产幅度为50 m^(3)/d较为适宜,上产期一般持续22个月,平均每1万m^(3)控制储量达标产气量保持在1.2~1.3 m^(3)/d,稳定生产阶段流压降幅应控制在0.08 MPa/a以下。将M块煤层气井划分为4类,依据达标产量对低产井和异常高产井进行调整,取得一定效果。该研究对煤层气井各开发阶段合理调配产量,以及区域开发调整具有指导意义。 展开更多
关键词 煤层气 目标产量 控制储量 开发阶段 动态调控
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有功预留式构网型光伏变流器电压调控方法
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作者 章天晗 吴俊飞 +4 位作者 周行 杨彬 洪建军 于淼 代一乐 《浙江电力》 2026年第3期49-61,共13页
低压台区分布式光伏渗透率持续提升,因源荷不匹配、无功支撑能力不足导致的电压越限问题日趋突出。为此,提出一种有功预留式构网型光伏变流器电压调控方法。在构网型VSG(虚拟同步机)变流器控制框架下引入最大功率跟踪/有功预留、无功自... 低压台区分布式光伏渗透率持续提升,因源荷不匹配、无功支撑能力不足导致的电压越限问题日趋突出。为此,提出一种有功预留式构网型光伏变流器电压调控方法。在构网型VSG(虚拟同步机)变流器控制框架下引入最大功率跟踪/有功预留、无功自适应调压/无功锁存等多模态,构建“无功优先调压、柔性有功兜底”的协同调压逻辑。基于状态空间法建立小信号模型,辨识主导极点并给出参数整定准则;采用对称分量法构建正负序输出阻抗,结合阻抗比判据评估并网稳定性。在Simulink平台构建典型越限台区的精细化模型,并集成所提控制策略开展仿真验证。结果表明,该策略可在越限初期快速释放调压裕度,有效实现柔性有功与无功自适应协同调压,抑制并网点电压上浮并提供电压与频率支撑,适用于存量与新增台区推广。 展开更多
关键词 有功预留 VSG 构网型光伏 电压越限治理
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Stochastic Optimization of Medium-and Short-term Reserve Arrangement for Preventive and Emergency Control Under Typhoon Disaster 被引量:2
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作者 Yunchu Wang Yusheng Xue +3 位作者 Dongliang Xie Yuge Chen Changming Chen Zhenzhi Lin 《Journal of Modern Power Systems and Clean Energy》 2025年第1期190-201,共12页
With the increase in the permeability of renewable energy and the frequency of extreme weather,the power system requires a large amount of flexible power regulation capacity.In order to realize the multi-day cooperati... With the increase in the permeability of renewable energy and the frequency of extreme weather,the power system requires a large amount of flexible power regulation capacity.In order to realize the multi-day cooperation of reserve resources,the stochastic optimization of medium-and short-term reserve arrangement considering the typhoon uncertainty is studied in this paper.Firstly,the extreme scenario generation and reduction method considering the typhoon path-intensity prediction uncertainty is constructed.Then,considering the combined cost of preventive and emergency control for adequacy in multiple scenarios,the reserve arrangement optimization model in extreme weather is built.In this model,the pre-dispatching strategies for multiple types of reserve resources are proposed to maintain the medium-and short-term coordination.Finally,case studies on a simplified 24-node power system of Zhejiang province,China are presented based on the data of the typhoon Fireworks in July 2021,and the result shows that the proposed reserve arrangement optimization model can reduce the total cost of power systems and the risk of operation under the typhoon disaster. 展开更多
关键词 reserve arrangement typhoon uncertainty preventive control for adequacy emergency control for adequacy stochastic optimization risk-based coordination
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面向表面处理园区的智能出入口控制管理系统的设计和实践
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作者 季伟伟 王锡力 《智能建筑与智慧城市》 2026年第1期147-149,共3页
文章通过对某大型园区实施案例的深入分析,详细介绍了出入口控制的关键技术,聚焦园区出入人员身份差异,构建了智慧人行系统和智慧车行系统两大模块。根据访客的不同身份,对门禁和闸机进行授权分级精细化管理,同时对物流运输车辆入园调... 文章通过对某大型园区实施案例的深入分析,详细介绍了出入口控制的关键技术,聚焦园区出入人员身份差异,构建了智慧人行系统和智慧车行系统两大模块。根据访客的不同身份,对门禁和闸机进行授权分级精细化管理,同时对物流运输车辆入园调度、危化品车辆行驶管理进行深入阐述。智能出入口控制管制系统旨在提升园区管理效率、优化资源配置,并为决策者提供有力支持。 展开更多
关键词 表面处理园区 出入口控制 车辆管理 访客预约 园区交通 危化品车辆
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The Significance of Hyperopic Reserve Monitoring and Its Value for Myopia Prevention and Control 被引量:1
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作者 Xin Guo 《China CDC weekly》 2025年第40期1263-1266,共4页
Myopia represents a critical public health challenge with far-reaching implications for future development,as global prevalence is projected to reach 49.8%by 2050(1–2).The Chinese government has implemented comprehen... Myopia represents a critical public health challenge with far-reaching implications for future development,as global prevalence is projected to reach 49.8%by 2050(1–2).The Chinese government has implemented comprehensive policies and proactive measures(3–6)to accelerate prevention efforts through systematic interventions.Traditional monitoring approaches have focused primarily on vision screening and diopter examination following myopia onset,thereby lacking early warning systems for tracking hyperopic reserve depletion.Commissioned by the National Disease Control and Prevention Bureau,our team has spearheaded a landmark large-scale monitoring project on hyperopic reserves among children and adolescents since 2020,encompassing ten provincial-level administrative divisions(PLADs;including Beijing,Liaoning,Zhejiang,Henan,Chongqing,Shaanxi,Guangdong,Shanxi,Hunan,and Shandong). 展开更多
关键词 diopter examination hyperopic reserve myopia prevention public health vision screening policies proactive measures myopia control systematic interventionstraditional
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新《矿产资源法》背景下中国油气资源储量管理研究与思考
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作者 陈红 张晨朔 张道勇 《天然气工业》 北大核心 2026年第2期159-166,共8页
2025年7月,新修订的《中华人民共和国矿产资源法》(以下简称《矿产资源法》)施行,首次确立矿产资源储量管理的法律地位。为了推动中国油气储量管理体系与新《矿产资源法》要求精准衔接,结合油气勘探开发特点,系统剖析了新《矿产资源法... 2025年7月,新修订的《中华人民共和国矿产资源法》(以下简称《矿产资源法》)施行,首次确立矿产资源储量管理的法律地位。为了推动中国油气储量管理体系与新《矿产资源法》要求精准衔接,结合油气勘探开发特点,系统剖析了新《矿产资源法》框架下油气储量管理的新要求,明确了管理目标定位,梳理了管理模式转型方向,并提出了构建管理新格局的实施路径。研究结果表明:①新《矿产资源法》下油气储量管理呈现全面化、精细化、严格化新要求,核心目标定位为全面掌握资源家底、服务找矿突破支撑增储上产、促进行业绿色高质量发展;②从管理维度升级、管理层级拓展、管理对象延伸3个维度,加强资源保护和储备两个方面推动油气储量管理改革;③从健全油气储量管理核心制度、构建系统化油气储量标准规范两个体系,建立健全油气储量报告质量管控、建立可采储量国家定期评价、建立常态化标准培训和学术交流3个机制,构建油气储量管理新格局的实现路径。结论认为,进一步打造权责清晰、流程规范、数据精准、效能提升的油气储量管理新格局,可以进一提高国家油气资源安全保障能力、为油气行业绿色高质量发展提供持续支撑。 展开更多
关键词 矿产资源法 油气储量 管理制度 标准体系 质量管控 全生命周期
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无线ECP制动技术在我国重载列车的应用
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作者 徐建喜 蒋勇 +3 位作者 吴吉恒 杨建平 石宏原 宋宸 《智慧轨道交通》 2026年第2期60-63,88,共5页
我国铁路运输正在向高速、重载、高密度方向发展,增加列车编组长度和载重是提升货运能力的有效手段之一。然而,大长度重载列车的开行也使列车的操控难度加大和纵向力加剧。相较于传统的空气制动系统,电控空气(ECP)制动技术能够有效降低... 我国铁路运输正在向高速、重载、高密度方向发展,增加列车编组长度和载重是提升货运能力的有效手段之一。然而,大长度重载列车的开行也使列车的操控难度加大和纵向力加剧。相较于传统的空气制动系统,电控空气(ECP)制动技术能够有效降低列车纵向力、减小列车的操控难度。目前广泛采用的缆接式ECP系统难以适应我国灵活多变的列车编组要求,随着无线传输设备的成熟,无线ECP制动技术得以广泛应用。文章基于单元列车和组合列车的无线自组网架构,结合无线ECP制动技术、线路特征感应技术和预约控制技术等,研究和探讨了如何降低列车纵向力和操控难度。目前,无线ECP制动技术已在我国万t级C_(80)列车上完成了装车运用试验,并验证了其系统网络的稳定性和可靠性。 展开更多
关键词 重载列车 电空制动 无线网络 特征感应 预约控制
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