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Baoziwan-Majiashan Area of Jiyuan Oilfield Analysis of Reservoir Characteristics and Main Control Factors in Long 4 5 Section
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作者 Zhengxi Cui Zhipeng Zhang Mingling Shen 《Open Journal of Yangtze Oil and Gas》 2024年第2期48-64,共17页
Based on the sheet, scanning electron microscope and high pressure mercury analysis method, this paper takes Jiyuan oilfield-Ma Jia mountain district 4 5 sandstone reservoir as the research object, from the reservoir ... Based on the sheet, scanning electron microscope and high pressure mercury analysis method, this paper takes Jiyuan oilfield-Ma Jia mountain district 4 5 sandstone reservoir as the research object, from the reservoir petrology, pore type and porosity, permeability, the system analyzed the reservoir characteristics and its control factors. The results show that the sandstone in the 4 5 section of Baoziwan-Majiashan area of Jiyuan oilfield is fine in size and high in filling content. The pore types were dominated by intergranular pores and dissolved pores, with a low face rate. The reservoir property is relatively poor, with mean porosity of 11.11% and mean permeability of 1.16 × 10<sup>−</sup><sup>3</sup> µm<sup>2</sup>. In the low porous, low otonic background, the development of relatively high pore hypertonic areas. Compaction and cementation should play a destructive role in reservoir properties, and dissolution should play a positive role in reservoir properties. Compaction adjusts the migration of clay minerals and miscellaneous bases in the original sediment in the study area, greatly reducing the porosity and permeability of the reservoir;the development of the cement cement, carbonate cementation and some quartz secondary compounds reduces the storage space;the dissolution effect, especially the secondary dissolution pores of the reservoir, which obviously improves the properties of the reservoir. 展开更多
关键词 Ordos Basin Jiyuan Area Reservoir Characteristics Reservoir control Factor Long 4 5 section
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Cause of over Water Quality Standard and Control Measures of State-controlled Sections in Northern Water-deficient Area of Jiangsu 被引量:5
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作者 胡永定 韩宝平 +1 位作者 钱新 袁兴程 《Meteorological and Environmental Research》 CAS 2010年第2期91-94,99,共5页
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r... Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology. 展开更多
关键词 State-controlled sections Cause analysis control measures Water-deficient area China
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Study on Safeguard System of Eco-tourism Compensation of Hukou Section during Ecological Water-control Project of Poyang Lake 被引量:1
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作者 龚双双 沈中印 +1 位作者 孙冬英 杨云仙 《Journal of Landscape Research》 2010年第12期58-62,72,共6页
Through analysis on the background to develop eco-tourism and necessity for ecological compensation,based on specific condition of Hukou County,in line with the situation to develop eco-tourism during ecological water... Through analysis on the background to develop eco-tourism and necessity for ecological compensation,based on specific condition of Hukou County,in line with the situation to develop eco-tourism during ecological water control project of Poyang Lake,residents' interest protection system and ecological benefit safeguard system for eco-tourism compensation were put forward. 展开更多
关键词 Poyang Lake ECOLOGICAL WATER control project ECO-TOURISM COMPENSATION Hukou section
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Effective extraction of photoneutron cross-section distribution using gamma activation and reaction yield ratio method
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作者 Zhi‑Cai Li Yue Yang +6 位作者 Zong‑Wei Cao Xin‑Xiang Li Yun Yuan Zong‑Qing Zhao Gong‑Tao Fan Hong‑Wei Wang Wen Luo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期103-111,共9页
Photoneutron cross-section(PNCS)data are important in various current and emerging applications.Although a few sophis-ticated methods have been developed,there is still an urgent need to study the PNCS data.In this st... Photoneutron cross-section(PNCS)data are important in various current and emerging applications.Although a few sophis-ticated methods have been developed,there is still an urgent need to study the PNCS data.In this study,we propose the extraction of PNCS distributions using a combination of gamma activation and reaction yield ratio methods.To verify the validity of the proposed extraction method,experiments for generating^(62,64)Cu and^(85m,87m)Sr isotopes via laser-induced pho-toneutron reactions were performed,and the reaction yields of these isotopes were obtained.Using the proposed extraction method,the PNCS distributions of^(63)Cu and^(86)Sr isotopes(leading to^(85m)Sr isotope production)were successfully extracted.These extracted PNCS distributions were benchmarked against available PNCS data or TALYS calculations,demonstrating the validity of the proposed extraction method.Potential applications for predicting the PNCS distributions of the 30 iso-topes are further introduced.We conclude that the proposed extraction method is an effective complement to the available sophisticated methods for measuring and evaluating PNCS data. 展开更多
关键词 Photonuclear data Photoneutron cross section Gamma activation Reaction yield TALYS calculation
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Soil and water loss in the Lancang River-Mekong River watershed (in Yunnan section, China) and its control measures 被引量:1
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作者 WANG Hong YAO Li xin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第1期92-99,共8页
According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and devel... According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and development of soil and water loss is analyzed. The conclusion is that: (1) generally, the situation of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is light, however, soil and water loss in some regions is serious, especially in the middle reach area of the river; (2) soil and water loss in the Lancang River Mekong River (in Yunnan section, China) watershed presents developing tendency and it is mainly caused by human beings. In accordance with these results, the control measures for soil and water loss are discussed. 展开更多
关键词 Lancang River Mekong River watershed (in Yunnan section China) soil and water loss control measures soil erosion mud rock flow LANDSLIDE
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Effect of mandrel on cross section quality of thin-walled tube numerical controlled bending 被引量:7
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作者 谷瑞杰 杨合 +2 位作者 詹梅 李恒 王光祥 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第6期1264-1274,共11页
The effect of mandrel with the structure of ball and socket on the cross section quality of thin-walled tube numerical controlled(NC) bending was studied by numerical simulation method, combined with theoretical (anal... The effect of mandrel with the structure of ball and socket on the cross section quality of thin-walled tube numerical controlled(NC) bending was studied by numerical simulation method, combined with theoretical (analysis) and experiment. Influencing factors of the mandrel include the count of mandrel heads, the diameter of mandrel and its position. According to the principle of NC tube bending, quality defects possibly produced in thin-walled tube NC bending process were analyzed and two parameters were proposed in order to describe the cross section quality of thin-walled tube NC bending. According to the geometrical dimension of tube and dies, the range of mandrel protrusion was derived. The finite element model of thin-walled tube NC bending was established based on the DYNAFORM platform, and key technological problems were solved. The model was verified by experiment. The effect of the number of mandrel heads, the diameter of mandrel and the protrusion length of mandrel on the cross section quality of thin-walled tube NC bending was revealed and how to choose mandrel parameters was presented. 展开更多
关键词 芯棒 数控弯曲 薄壁管 横截面质量
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Close coupling calculations for excitation partial cross sections in Ne-HF collisions
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作者 余春日 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2097-2102,共6页
This paper reports that an exact quantum close coupling calculation is carried out for rotational excitation in Ne HF collisions on the available anisotropic potential. Partial cross sections are obtained separately a... This paper reports that an exact quantum close coupling calculation is carried out for rotational excitation in Ne HF collisions on the available anisotropic potential. Partial cross sections are obtained separately at the incident energies of 48.35, 75, 120 and 150meV. The reliability of the results is demonstrated by comparison with previously published theoretical findings. Based on the calculations, the effect of the potential energy surface on the excitation partial cross sections is discussed in detail. 展开更多
关键词 close coupling calculation excitation partial cross section Ne HF collision
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Study on the methods of precision controlling for the manufacture of hull curvature sections
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作者 LIU Yu-jun HU Ri-qiang DENG Yan-ping 《Journal of Marine Science and Application》 2006年第4期22-26,共5页
The precision controlling technology is a key step for the modern ship construction, with the precision controlling of the ship-hull curvature as one of bottlenecks in shipbuilding, where the initial is to present a c... The precision controlling technology is a key step for the modern ship construction, with the precision controlling of the ship-hull curvature as one of bottlenecks in shipbuilding, where the initial is to present a compensation value for the ship-hull plate precisely. The compensation value of the curvature plate is composed of two parts: the construction compensation, which results in the process of heating construction of curvature plate, and the assembling compensation, which results in welding ribbed stiffeners onto the curvature plate. Based on the developed computation system for the local contraction value, this paper presents a method to establish the experimented samples for the assembling compensation by means of numerical experiments, and another method to establish the practical mathematical model for the construction compensation of curvature plate. Furthermore, it introduces the experimental measuring method for the assembling compensation of the curvature plate, based on which the related database system has been developed. Numerical examples are analyzed to demonstrate the process to establish mathematical model for the assembling compensation values. 展开更多
关键词 hull curvature sections MANUFACTURE precision controlling compensation values
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Calculation of production cross sections of γ-rays from thermal-neutron captures
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作者 ZHOUChun-Mei WUZhen-Dong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2004年第6期328-334,共7页
The calculation methods of production cross sections of γ-rays for thermal-neutron captures are briefly presented. The check of intensity balance is made. The examples are given to illustrate its application.
关键词 中子反应 γ-射线 热中子俘获 数据计算 乘积横截面
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Principle of Mangling Correction of Plate-welding Section Steel and its Application
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作者 ZHANG Xian, JI Shi-ming, ZHAO Zhang-feng, YUAN Ju-long, ZHANG Li-bin (Institute of Mechatronics Engineering, Zhejiang University of Technology, Hangzhou 310032, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期19-,共1页
Thanks to the fantastic development of power, transportation, chemical engineering, architecture and other fields, there has been an increasing demand for new type of section steel with large sections used for constru... Thanks to the fantastic development of power, transportation, chemical engineering, architecture and other fields, there has been an increasing demand for new type of section steel with large sections used for construction frame, such as type-H, type-T, and type-C section steel. New types of section steel usually are long and with large cross section. Therefore, for the sake of the cost, steel plate welding structure is used home and abroad. During the welding process, welding distortion seems unavoidable. Presently, proper welding machinery, technique and standards are adopted to minimize the distortion. Angular distortion is corrected with oil press and angular distortion corrector, while horizontal distortions like sickle curve and arch are mainly done with flame. Flame correction is of great labor intensity and is also time and material consuming. Besides, the correction is affected by the operators’ skill and mood, which, to some extent, limits the productivity. In this paper, a new technique of section steel distortion correction with high efficiency and adaptability and yet low investment and cost will be proposed for the development of new-type section steel. The correction principles and capability calculation should be done some research on, which will be introduced. The practice done on section steel with a wing edge of 40~60 mm, proves satisfactory: compared with oil-press correction, continual mangling correction saves equipment investment by three quarters, installed capacity by three quarters and investment by three quarters and with a much higher efficiency. Particularly in the distortion correction of heavy welding structures, mangling correction stands out from the crowd. Mangling correction proves to be the best solution to the continual horizontal distortion correction of welding section steel. 展开更多
关键词 mangling correction welding section steel capability calculation
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River Cutoff Practices on Lower Jingjiang Section of Changjiang River in the Last 30 Years
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作者 PAN Qing-shenProfessor-senior Engineer, Yangtze River Scientific Research Institute, Changjiang Water Resources Commission, Wuhan 430010, China 《人民长江》 北大核心 2002年第S1期40-45,共6页
River cutoff works have been implemented on Lower Jingjiang section for 30 years. Engineering practices have shown that channel straightening has been the river regulation measure for the permanent control of the mean... River cutoff works have been implemented on Lower Jingjiang section for 30 years. Engineering practices have shown that channel straightening has been the river regulation measure for the permanent control of the meandering Lower Jingjiang section. River cutoff have been carried out in accordance with the evolution property of meandering rivers and these works have brought about expected benefits. It has also been noted that certain aspects in river cutoff had not been fully understood. River cutoff is a dynamic engineering. River channel evolution properties shall be fully understood so as to adroitly guide actions according to circumstances in cutoff works. In addition, river channel evolution observation and engineering effectiveness monitoring should be strengthened with a view to update the designs. The diversion canals for channel shortening are of great importance that will account for the success or failure of river cutoff works. The newly formed river channels and the river regime control works on the adjacent upper and lower reaches are guarantees for river cutoff works to be brought into play in the long run. 展开更多
关键词 RIVER CUTOFF works RIVER regime control RIVER training MEANDERING channel LOWER Jingjiang section of CHANGJIANG RIVER
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Quality assessment of intraoperative frozen sections: An analysis of 261 consecutive cases in a resource limited area: Morocco
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作者 Laila Chbani Sekal Mohamed +2 位作者 Tawfik Harmouch Hinde El Fatemi Afaf Amarti 《Health》 2012年第7期433-435,共3页
Purpose: To evaluate the accuracy and limits of a frozen section analysis in our department in order to develop a quality control. Materials and methods: all frozen sections reported at our department between 1st Janu... Purpose: To evaluate the accuracy and limits of a frozen section analysis in our department in order to develop a quality control. Materials and methods: all frozen sections reported at our department between 1st January 2010 and 31st December 2010, have been retrospectively evaluated. The frozen section results were compared to permanent paraffin section results. Results: Frozen sections and final diagnosis agreed in 95% and disagreed in 5% (13 cases), 6.6% of the cases were deferred (17 cases). The most common pathological processes encountered were presence/typing of neoplasm (85.4%) and assessment of surgical margins (7.3%). Conclusion: The accuracy of frozen sections diagnosis at our department can be interpreted as comparable with the most international quality control series and is valuable to assist surgeons in their decision. 展开更多
关键词 FROZEN sectionS Quality control DISCREPANCIES Accuracy
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Effect of Gum-Chewing after Cesarean Section on Gastrointestinal Function Recovery: A Systematic Review and Meta-Analysis of Randomized Trials
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作者 Liu Zhang Yanlin Heng +1 位作者 Hong Hu Xin Liang 《Yangtze Medicine》 2019年第2期79-89,共11页
Objective: To evaluate the effect of chewing sugar-free gum on gastrointestinal function recovery after cesarean section. Methods: Randomized controlled trials comparing the use of chewing gum in postoperative recover... Objective: To evaluate the effect of chewing sugar-free gum on gastrointestinal function recovery after cesarean section. Methods: Randomized controlled trials comparing the use of chewing gum in postoperative recovery with a control group were retrieved from the databases including Pubmed, Cochrane Library, Science Direct, Web of Science, CBM, CNKI, Wanfang and VIP, et al. After screening literatures, evaluating the quality of studies, extracting data, the RevMan5.3 software was used for data analysis. Results: A total of 13 RCTs including 2233 patients were analyzed in the study. The results showed that chewing gum after cesarean delivery can effectively shorten the recovery time of bowel sounds, passage of flatus and first defecation (all P Conclusion: Chewing sugar-free gum after cesarean section can promote the early recovery of gastrointestinal function, but the side effects of chewing gum are still unclear, which needs more clinical, large sample and high-quality studies to further verify. 展开更多
关键词 CESAREAN section Gum-Chewing GASTROINTESTINAL Function RANDOMIZED controlled TRIAL Systematic Review
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ON THE LIMIT CASE OF THE STEP-REDUCTION METHOD FOR CALCULATING NON-UNIFORM BEAM WITH VARIOUS SECTIONS
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作者 伍炯宇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第8期795-800,共6页
In this paper, the step reduction method is discussed, which was advanced by Prof. Yeh Kai-yuan for calculating a non-uniform beam with various sections. The following result is proved. The approximate solution by thi... In this paper, the step reduction method is discussed, which was advanced by Prof. Yeh Kai-yuan for calculating a non-uniform beam with various sections. The following result is proved. The approximate solution by this method approaches the true solution if the number of the steps approaches the infinity. However, the measure of the error between the limit solution and the ture solution is not in the pure mathematics sense but in the mechanics sense. 展开更多
关键词 ON THE LIMIT CASE OF THE STEP-REDUCTION METHOD FOR CALCULATING NON-UNIFORM BEAM WITH VARIOUS sectionS
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纳布啡不同镇痛泵参数用于剖宫产术后镇痛的比较 被引量:2
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作者 叶卉 孙杰 +2 位作者 汪佳佳 黄露欣 谢珏 《临床麻醉学杂志》 CAS CSCD 北大核心 2024年第3期252-256,共5页
目的比较三种不同参数纳布啡患者自控静脉镇痛(PCIA)用于剖宫产术后镇痛的效果。方法选择剖宫产术后的产妇179例,年龄18~45岁,BMI 20~35 kg/m 2,ASAⅠ或Ⅱ级,术后均给予PCIA(纳布啡2 mg/kg+托烷司琼8 mg/100 ml,间隔时间15 min,极限量10... 目的比较三种不同参数纳布啡患者自控静脉镇痛(PCIA)用于剖宫产术后镇痛的效果。方法选择剖宫产术后的产妇179例,年龄18~45岁,BMI 20~35 kg/m 2,ASAⅠ或Ⅱ级,术后均给予PCIA(纳布啡2 mg/kg+托烷司琼8 mg/100 ml,间隔时间15 min,极限量10 ml/h)。将产妇随机分成三组:对照组(C组,背景量2 ml/h,单次按压2 ml,n=60)、低背景量组(L组,背景量1 ml/h,单次按压3 ml,n=62)和无背景量组(N组,背景量0 ml/h,单次按压4 ml,n=57)。记录术后2、6、12、24、48 h静息和活动时VAS疼痛评分、纳布啡消耗量。记录术后48 h内PCIA按压情况、术后首次肛门排气时间、术后住院时间、Ramsay镇静评分和术后恶心呕吐、头晕、感染等不良反应的发生情况。结果与C组比较,N组术后6、12 h静息时VAS疼痛评分明显升高(P<0.05),L组和N组术后24、48 h纳布啡消耗量明显减少,术后首次肛门排气时间明显缩短,头晕发生率明显降低(P<0.05),N组术后住院时间明显缩短(P<0.05)。与L组比较,N组术后12 h静息和活动时VAS疼痛评分明显升高,术后48 h纳布啡消耗量明显减少,总按压次数和有效按压次数明显增加,术后首次肛门排气时间明显缩短(P<0.05)。三组Ramsay镇静评分和术后恶心呕吐、感染发生率差异无统计学意义。结论低背景量(1 ml/h)纳布啡PCIA可在充分镇痛的同时,减少阿片类药物用量,降低相关不良反应发生率,缩短术后首次肛门排气时间,可作为纳布啡PCIA用于剖宫产术后镇痛参数设置的优先选择。 展开更多
关键词 剖宫产 纳布啡 术后镇痛 患者自控静脉镇痛 参数设置
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急倾斜特厚煤层冲击地压防治探索与总结 被引量:2
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作者 窦林名 王永忠 +3 位作者 卢方舟 贺虎 何江 张强 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第1期84-94,共11页
急倾斜特厚煤层开采顶板破断运动复杂,应力和能量演化规律特殊,在深部“三高一扰动”影响下,冲击地压防治不容乐观。基于某矿2016年冲击地压事故后急倾斜特厚煤层水平分段开采冲击地压防治经验,从急倾斜特厚煤层水平分段开采冲击地压发... 急倾斜特厚煤层开采顶板破断运动复杂,应力和能量演化规律特殊,在深部“三高一扰动”影响下,冲击地压防治不容乐观。基于某矿2016年冲击地压事故后急倾斜特厚煤层水平分段开采冲击地压防治经验,从急倾斜特厚煤层水平分段开采冲击地压发生机理、瓦斯突出与冲击地压综合防治和冲击地压管理详细介绍了该矿7年来急倾斜特厚煤层冲击地压防治经验。冲击地压发生机理方面,建立了顶板岩层倾斜悬臂梁模型,揭示了顶、底板覆岩结构破断失稳演化过程,划分了夹持煤体受力状态分区,提出了急倾斜特厚煤层冲击“夹持理论”。瓦斯突出与冲击地压综合防治方面,基于冲击地压灾害控制解危技术的强度弱化减冲理论,结合原有防突措施体系,提出了既能防冲且对防突有利的解危措施,形成了某矿瓦斯/CO_(2)突出-冲击地压“双防”技术体系,建立了适用于某矿急倾斜特厚煤层水平分段开采的冲击地压防治体系,以钻屑量和瓦斯吸解值验证了瓦斯突出防治的强度保障,同时以加强实施卸压措施工作面的微震事件分布及各能级总频次和能量对比,论证说明了卸压方案防治效果的有效性。冲击地压管理方面,形成了预测评价、监测预警、治理预防、效果检验、安全防护和教育培训“六位一体”综合防治架构,基于《煤矿安全规程》和《防治煤矿冲击地压细则》等各项规定,制定了Q/YJMD-—FC 0104-2022《窑街煤电集团有限公司煤矿冲击地压防治第四部分:冲击地压防治技术规范》。 展开更多
关键词 冲击地压 急倾斜特厚煤层 冲击“夹持理论” 安全防控 水平分段开采
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速度350km/h高速铁路长大下坡地段闭塞分区设置方法研究
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作者 张守帅 张雨洁 +2 位作者 闫海峰 田长海 骆泳吉 《铁道学报》 EI CAS CSCD 北大核心 2024年第1期72-80,共9页
通过分析长大下坡道闭塞分区长度对CTCS-3级和后备CTCS-2级列控系统的影响,指出二者对闭塞分区长度的需求完全相反,并针对CTCS-3级列控系统的行车许可回缩、速度突降等问题的产生原因进行分析。阐述坡度、闭塞分区长度与不同列控模式下... 通过分析长大下坡道闭塞分区长度对CTCS-3级和后备CTCS-2级列控系统的影响,指出二者对闭塞分区长度的需求完全相反,并针对CTCS-3级列控系统的行车许可回缩、速度突降等问题的产生原因进行分析。阐述坡度、闭塞分区长度与不同列控模式下列车运行速度、追踪间隔时间等要素之间的关系,制定闭塞分区设置的基本原则。检算典型坡度下闭塞分区长度设置的合理区间范围及相应追踪间隔时间,指出坡度超过-30‰后将无法兼顾不同列控等级下的运行速度。设计模拟退火算法,根据闭塞分区设置原则及闭塞分区取值规律,给出压缩求解空间、提高求解效率的方法。以郑万高速铁路长大下坡地段为例,对闭塞分区设置进行优化,在不考虑其他约束的前提下,与设计院优化方案相比,本求解优化方案在确保CTCS-3级控车模式下允许速度可达350 km/h的同时,将CTCS-2级控车模式下的允许速度提高30 km/h,追踪间隔时间压缩23 s。 展开更多
关键词 高速铁路 长大下坡道 CTCS-3级列控系统 闭塞分区 行车许可
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长江弯曲航道船舶航迹控制方法研究
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作者 黄立文 纪孟阳 +2 位作者 刘进来 于德清 贺益雄 《武汉理工大学学报(交通科学与工程版)》 2024年第5期991-998,共8页
文中建立考虑舵机伺服系统特性和风、流干扰的线性船舶动力学模型,确定仿真实验船舶的各个必要参数.引入最优控制策略,以航速为自变量设计不同航速下基于最优控制策略的PID(proportion integral differential)航向控制器OP-PID Controll... 文中建立考虑舵机伺服系统特性和风、流干扰的线性船舶动力学模型,确定仿真实验船舶的各个必要参数.引入最优控制策略,以航速为自变量设计不同航速下基于最优控制策略的PID(proportion integral differential)航向控制器OP-PID Controller(optimal PID controller),在不同航速下分别采取PID和OP-PID进行了航向控制仿真.在航向控制器的基础上,结合航段跟踪决策算法、改进的LOS(line-of-sight)制导方法获取航向偏差,以航向偏差驱动OP-PID间接航迹控制器.以OP-PID和改进的LOS组成的航迹控制方法进行了静水环境中和外界干扰下的航迹控制仿真实验.结果表明:基于改进LOS制导方法和OP-PID航向控制器可以较好地跟踪弯曲航道计划航线,舵角和转向幅度均小于现有航迹控制器. 展开更多
关键词 弯曲航道 最优控制策略 航向控制 航迹控制
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基于区段的地下空间环路通风排烟设计方法
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作者 王洁 赵炳欣 姜学鹏 《隧道建设(中英文)》 CSCD 北大核心 2024年第1期155-162,共8页
为实现多匝道、多地块、内部空间复杂的地下空间环路烟气控制,提出一种区段式排烟方法:将地下空间环路与地块通过防火门分隔,形成独立的构筑物,结合隧道结构,确定风机房位置,划分区段,使烟气在一定区域内排出。以滨江地下环路为例,在隧... 为实现多匝道、多地块、内部空间复杂的地下空间环路烟气控制,提出一种区段式排烟方法:将地下空间环路与地块通过防火门分隔,形成独立的构筑物,结合隧道结构,确定风机房位置,划分区段,使烟气在一定区域内排出。以滨江地下环路为例,在隧道主线上均匀布置6个排烟风机房,并以此为节点,将隧道划分为8个区段。当火灾发生时,开启所在区段两端的风机进行排烟。由于各区段不设置固定分隔,整个风道是贯通的,因而各个风机房里的风机可互相作为备用排烟风机,以降低成本。采用数值模拟软件建立模型,对排烟口开启数量和间距进行模拟,确定排烟量为90 m^(3)/s、排烟口间距为30 m、开启8个排烟口的排烟方案。从人员疏散环境以及排烟效率对典型区段进行分析,结果表明:烟气控制在一定的范围内,人员疏散环境安全,排烟效率达到90%,证明方案合理可行。 展开更多
关键词 火灾烟气控制 地下空间环路 通风排烟设计方法 区段划分
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互联网+背景下虚拟教研室内涵建设
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作者 张宏伟 王新环 +1 位作者 高如新 戴胜华 《电气电子教学学报》 2024年第4期34-38,共5页
针对高校基层教学组织建设存在的一些问题,分析了虚拟教研室的成立背景、建设内涵,探讨了虚拟教研室的组织架构及保障条件,提出了以师资能力提升为导向,以课程建设为核心,以教学资源共享为途径,以开放课题研究为抓手的内涵建设途径。实... 针对高校基层教学组织建设存在的一些问题,分析了虚拟教研室的成立背景、建设内涵,探讨了虚拟教研室的组织架构及保障条件,提出了以师资能力提升为导向,以课程建设为核心,以教学资源共享为途径,以开放课题研究为抓手的内涵建设途径。实践应用表明,通过加强虚拟教研室内涵建设,极大地提升了各参与高校的积极性,有效促进了各参与高校轨道交通信号与控制专业的专业建设水平,提升了人才培养质量。 展开更多
关键词 虚拟教研室 轨道交通信号与控制专业 内涵建设
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