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Design of Na-K Alloy Differential Pressure Sensor with On-line Monitoring Function
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作者 WU Linghui XU Dong 《International Journal of Plant Engineering and Management》 2018年第3期129-133,共5页
Because the melting point of the alkalis is very high and the metal activity is strong, the common pressure sensor can't be used to measure pressure of liquid metal. In this paper, a differential transformer differen... Because the melting point of the alkalis is very high and the metal activity is strong, the common pressure sensor can't be used to measure pressure of liquid metal. In this paper, a differential transformer differential pressure sensor for measuring liquid alkalis pressure is designed, the working principle and specific design plan of the sensor are introduced, the standard current signal ( 4 -20 mA) or digital communication RS485 can be output according to the needs, and the functions of remote monitoring and data optimization can be realized through the LAN interface. 展开更多
关键词 BELLOWS differential pressure sensor spring mechanism high temperature on-line monitoring
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STUDY ON VARIATION OF SETTING AND STOPPING PRESSURES OF SAFETY VALVE WITH STRUCTURAL MODIFICATION 被引量:1
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作者 Lee Jinho Kwangzin Valve Industrial Co ,Ltd,Korea Kim Harkbong Kim Moonsang School of Aerospace and Mechanical Engineering,Hankook Aviation University,Korea 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期127-138,共12页
The possibility of pressure control with the structural change of a safety valve is investigated Safety valve is commonly used as safety devices for numerous applications which include boilers,ships,industrial plant... The possibility of pressure control with the structural change of a safety valve is investigated Safety valve is commonly used as safety devices for numerous applications which include boilers,ships,industrial plants,and piping Setting and stopping pressures of a safety valve, p set and p sto ,are traditionally adjusted with a fine tuning of seat ring and valve ring heights, h sr and h vr However, it is not easy to achieve the proper setting and stopping pressures of a safety valve in practice The depth of inside and outside grooves in a valve, d i and d o are modified and their effects on setting and stopping pressures of a safety vlave are tested The most appropriate values appear 1 0 mm in d i and 0 5~1 0 mm in d o,respectively The valve ring height, h vr ,shows that the best results can be achieved at 2 3 mm for setting pressures of 0 1~0 4 MPa and 1 0 mm for setting pressures of 0 5~1 0 MPa The stopping pressures increases with the increase of seat ring height, h sr , upto certain h sr value and then becomes independent to the seat ring height This implies that there exists the optimum h sr ,which provides the largest flow rate and the proper stopping pressure Stopping pressures of a safety valve are adjusted with the seat ring and valve ring heights This study,however,demonstrated that the modification of value grooves also changes setting and stopping pressures of a safety valve Therefore,the proper selection in dimensions of the inside and outside grooves should be considered for the safety valve design 展开更多
关键词 Safety valve Compressive flow Isentropic flow theory Isentropic comressibility theory setting pressure Stopping pressure Continuity equation Momentum equation
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On-line Condition Monitoring and Diagnostic Network System for Rotating Machine Set 被引量:1
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作者 Li Fucai, He Zhengjia, Zi Yanyang School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, P. R. China 《International Journal of Plant Engineering and Management》 2000年第4期136-141,共6页
Several industrial computers and a server are combined to set up the on-line monitoring and diagnostic system of turbo-generator sets. The main function of the system is to monitor machine sets' running condition.... Several industrial computers and a server are combined to set up the on-line monitoring and diagnostic system of turbo-generator sets. The main function of the system is to monitor machine sets' running condition. Through analyzing running data, technicians can detect whether there exist faults and where they occur. To share and transmit the dynamic information of the turbo-generator sets, a distributed network system is introduced. NetWare network operating system is used in the LAN (Local Area Network) system. The LAN is extended to realize the sharing of data and remote transmission of information. Furthermore, functions of monitoring and diagnostic clients are listed. 展开更多
关键词 rotating machine set on-line monitoring and diagnostic network system
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Effect of Implanted Chip System on Blood Pressure Regulation in Rabbits 被引量:1
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作者 高兴亚 王汉军 +4 位作者 朱国庆 郭瑞 张枫 张颖 陆祖宏 《Journal of Nanjing Medical University》 2004年第6期279-282,共4页
Objective: To evaluate the efficiency of an implanted chip system on blood pressure regulation. Methods: The mean arterial pressure (MAP) and heart rate (HR) were recorded in anesthetized rabbits. Based on the set poi... Objective: To evaluate the efficiency of an implanted chip system on blood pressure regulation. Methods: The mean arterial pressure (MAP) and heart rate (HR) were recorded in anesthetized rabbits. Based on the set point theory, an implanted chip system was designed to regulate the blood pressure by stimulating the aortic depressor nerve (ADN) according to the feedback of blood pressure. The blood pressure regulation induced by the implanted chip system was carried out twice (lasted for 15 min and 60 min respectively) and the change of MAP and HR during the regulation was compared with the control. Results: There was a significant decrease of MAP during the first regulation ([-32.0 ± 6.6] mmHg) and second regulation ([-27.4 ± 6.2] mmHg) compared with the control (P<0.01). The HR was also significantly decreased during regulation compared with the control. Both MAP and HR returned to the baseline immediately without rebound after the regulation ceased. Conclusion: The implanted chip system can regulate the blood pressure successfully and keep the blood pressure in a lower constant level without adaptation. 展开更多
关键词 implanted chip blood pressure set point HYPERTENSION
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CATASTROPHE FRACTURE OF THIN-WALL PRESSURE TUBES
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作者 WEI De-min(魏德敏) +1 位作者 YANG Gui-tong(杨桂通) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第2期146-149,共4页
Catastrophe theory was used to investigate the fracture behavior of thin-wall cylindrical tubes subjected to internal explosive pressure. Based on the energy theory and catastrophe theory, a cusp catastrophe model for... Catastrophe theory was used to investigate the fracture behavior of thin-wall cylindrical tubes subjected to internal explosive pressure. Based on the energy theory and catastrophe theory, a cusp catastrophe model for the fracture vas established, and a critical condition associated with the model is given. 展开更多
关键词 pressure tube brittle fracture CUSP catastrophe bifurcation set
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Level-set法预报液舱内剧烈晃荡引起的冲击压强(英文) 被引量:9
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作者 朱仁庆 方智勇 +1 位作者 张照钢 陈正云 《船舶力学》 EI 北大核心 2008年第3期344-351,共8页
基于Level-set 法就部分装载液体的液舱内剧烈晃荡引起的冲击压强进行了二维数值计算。为了模拟大幅晃荡引起的冲击压强, 重点对数值计算较为敏感的自由液面处的物性参数、初始化方程的求解等进行了数值处理。通过对某一矩形液舱内的液... 基于Level-set 法就部分装载液体的液舱内剧烈晃荡引起的冲击压强进行了二维数值计算。为了模拟大幅晃荡引起的冲击压强, 重点对数值计算较为敏感的自由液面处的物性参数、初始化方程的求解等进行了数值处理。通过对某一矩形液舱内的液体晃荡的计算, 得到了自由表面位置和压强的时间历经曲线。计算结果同实验值的比较表明: 本方法可以用于计算预报大幅晃荡引起的载荷。 展开更多
关键词 Level—set 液体晃荡 冲击压强
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Labetalol versus Hydralazine in the Management of Severe Pre-Eclampsia at Tertiary Hospitals in a Low-Resource Setting: A Randomised Controlled Trial
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作者 Uzoma Otutoaja Adeyemo Olabisi Timothy +7 位作者 Emmanuel Olumide Adewara Olufunmilayo Victoria Adebara Augustine Adebayo Adeniyi Babatunde Sunday Awoyinka Raymond Akujuobi Okere Idowu Oluseyi Adebara Adewumi Bakare Mojisola Olumide Ayankunle 《Open Journal of Obstetrics and Gynecology》 2023年第6期1058-1067,共10页
Objective: Intravenous labetalol and hydralazine are both considered first-line medications for the management of acute-onset, severe hypertension in pregnant and postpartum women. The study compared the efficacy and ... Objective: Intravenous labetalol and hydralazine are both considered first-line medications for the management of acute-onset, severe hypertension in pregnant and postpartum women. The study compared the efficacy and safety profile of intravenous labetalol and hydralazine in the control hypertension in severe pre-eclampsia. Materials and Methods: One hundred patients who presented with severe pre-eclampsia were randomized into two study groups. The fifty patients in each arm of the study received either intravenous labetalol or intravenous hydralazine for the control of blood pressure. Results: The mean age of the labetalol subjects was 28.6 ± 5.47 years while that of their hydralazine counterparts was 29.12 ± 5.77 years. The majority of respondents in both groups were primigravidae (76% vs. 78%) (P = 0.813). The number of doses of drug needed to significantly lower the mean systolic blood pressure was slightly lower in the labetalol group (2 doses) compared to the hydralazine group (5 doses) (t = 0.803<sup>Y</sup>, P = 0.977). The incidence of headaches which were the commonest complaints was comparable in both groups 8% and 10% of respondents respectively (P > 0.05). Conclusion: Although both intravenous labetalol and hydralazine are useful in patients with severe pre-eclampsia, the response to labetalol was better with comparable side effects. 展开更多
关键词 Blood pressure HYDRALAZINE LABETALOL Low-Resource setting Severe Pre-Eclampsia Side Effects
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机械性吸呼仪参数设置对模拟肺呼气峰流速、呼气容量的影响研究
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作者 吕玉颖 曹志新 《医疗卫生装备》 CAS 2024年第6期65-70,共6页
目的:探讨使用机械性吸呼仪(mechanical in-exsufflation,MIE)治疗中的吸气压力设置参数(set inspiratory pressure,SIP)、呼气压力设置参数(set expiratory pressure,SEP)及SIP/SEP对模拟肺呼气峰流速(peak expiratory flow,PEF)和呼... 目的:探讨使用机械性吸呼仪(mechanical in-exsufflation,MIE)治疗中的吸气压力设置参数(set inspiratory pressure,SIP)、呼气压力设置参数(set expiratory pressure,SEP)及SIP/SEP对模拟肺呼气峰流速(peak expiratory flow,PEF)和呼气容量(expiratory volume,EV)的影响,以为临床治疗中增强气道廓清的效果提供参考。方法:将MIE与模拟肺连接,在模拟肺无自主呼吸状态下分别针对健康成人、肺部感染成人、慢性阻塞性肺疾病成人、急性呼吸窘迫综合征成人设置气道阻力及肺顺应性。MIE压差(SIP与SEP的差值)分别设置为60、40、30 cmH_(2)O(1 cmH_(2)O=98.06 Pa),在固定压差下,SIP/SEP设置为1∶1、1∶2、2∶3。在每种参数设置状态下,MIE均工作5个周期,记录PEF、EV的平均值。分析MIE治疗中PEF的出现时间,对比不同参数设置下PEF、EV的平均值,并分析SIP及SEP分别与PEF、EV的相关性。采用SPSS 20.0统计学软件进行数据分析。结果:模拟肺在不同生理条件下,MIE治疗中的PEF均出现在呼气初始,当压力释放的瞬间产生最大的PEF。MIE设置的压差越大,产生的PEF、EV越大;在压差相同情况下,SIP/SEP为1∶1时产生的PEF、EV最大。SIP与PEF、EV的斯皮尔曼相关系数为0.919、0.990,SEP与PEF、EV的斯皮尔曼相关系数为-0.737、-0.674,SIP与PEF、EV的相关性高于SEP与PEF、EV的相关性。结论:MIE治疗中设置压差越大,产生的气道廓清效果越好;在压差相同情况下,将SIP/SEP设置为1∶1,能够产生咳嗽效应的最大化,从而增强气道廓清的效果。 展开更多
关键词 机械性吸呼仪 模拟肺 呼气峰流速 呼气容量 吸气压力设置参数 呼气压力设置参数
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天然气余压发电透平发电机组控制特性研究
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作者 蒋鑫 朱万炫 +4 位作者 李和平 张雪辉 许剑 韩汶昕 徐江荣 《储能科学与技术》 CAS CSCD 北大核心 2024年第9期3287-3298,共12页
本文研究了透平发电机组的物理模型,重点详细介绍了透平膨胀机调速系统、同步发电机、励磁系统的工作原理。并据此利用MATLAB/Simulink建立起透平发电机组数学模型,主要包括透平膨胀机及其调速系统、同步发电机及励磁系统、电力负载模... 本文研究了透平发电机组的物理模型,重点详细介绍了透平膨胀机调速系统、同步发电机、励磁系统的工作原理。并据此利用MATLAB/Simulink建立起透平发电机组数学模型,主要包括透平膨胀机及其调速系统、同步发电机及励磁系统、电力负载模型等。然后根据建立的仿真模型对透平发电机组运行工况进行了常规PID仿真研究,在此基础上,对系统的控制方法进行优化,采用模糊PID控制进行了空载启动和投切负载的仿真研究,根据仿真结果对比了常规PID和模糊PID的控制性能,仿真结果显示模糊PID控制器比常规PID控制器的启动时间更短、超调量更小,使得发电机组的响应过程更加快速、稳定。 展开更多
关键词 余压发电 透平发电机组 仿真模型 模糊PID
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CO_(2)气腹压力预设阈值设定方案构建对腹腔镜手术患者血流动力学及并发症的影响
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作者 邓水珠 付丽明 +11 位作者 林焕明 李学山 陈申平 谢秋红 罗发江 范双炽 罗丽琴 唐素华 刘燕梅 陈艳燕 李梅岚 邹清秀 《齐齐哈尔医学院学报》 2024年第21期2063-2067,共5页
目的探讨腹腔镜下CO_(2)气腹压力预设阈值设定方案的构建,及对术中血流动力学和并发症的影响。方法选择2020年3月-2021年5月本院收治的腹腔镜手术患者616例为研究对象,采用回顾性病例研究及现况调查相结合方式,设计2版调查表,进行3轮调... 目的探讨腹腔镜下CO_(2)气腹压力预设阈值设定方案的构建,及对术中血流动力学和并发症的影响。方法选择2020年3月-2021年5月本院收治的腹腔镜手术患者616例为研究对象,采用回顾性病例研究及现况调查相结合方式,设计2版调查表,进行3轮调研,符合组间匹配原则下分为观察组283例(其中肝胆外科124例、妇科133例、胃肠外科26例)和对照组333例(肝胆外科139例、妇科159例、胃肠外科35例)。比较两组患者气管插管后5 min(T0)、手术开始(T1)、手术开始0.5 h(T2)、手术结束(T3)四个时点的收缩压(SBP)、舒张压(DBP)、心率(HR)及呼末二氧化碳分压(ETCO_(2))指标变化值;两组患者术后发生皮下气肿及术后不良反应例数。经汇总分析整理,构建一套实用的各类腔镜手术的CO_(2)气腹压力值的设定指标。结果横向比较:T1时点:两组患者SBP、DBP、HR值较T0时点降低(P<0.05);T2时点:观察组DBP值较T1时点上升(P<0.05);T3时点:两组SBP值、观察组DBP值及HR值较T2时点上升(P<0.05);两组ETCO_(2)值各时点较上个时点均上升(P<0.05)。纵向比较:两组患者T0、T1、T2各时点HR值有变化(P<0.05);两组患者T3时点SBP、DBP有变化(P<0.05)。观察组患者术后皮下气肿、恶心、呕吐、苏醒期躁动及肩痛的发生率均低于对照组(P<0.05)。结论采用低气腹压力,有效提升苏醒质量,减少术后不良反应发生率。构建手术外科细化标准的CO_(2)气腹压力阈值,实施动态精准预设为术中患者血流动力学改变提供依据。 展开更多
关键词 腹腔镜手术 CO_(2)气腹压力 预设阈值设定 血流动力学及并发症
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带式输送机托辊组振动噪声仿真分析及参数优化
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作者 郝洪涛 刘建昊 《煤炭工程》 北大核心 2024年第8期218-224,共7页
带式输送机托辊组产生的振动噪声受多因素联合影响,为解决其振动噪声过大问题,文章提出一种基于有限元-边界元理论对托辊组振动噪声分析与优化的方法。首先,对托辊组进行模态分析与动力学仿真,探明托辊组的振动特性;然后,基于有限元-边... 带式输送机托辊组产生的振动噪声受多因素联合影响,为解决其振动噪声过大问题,文章提出一种基于有限元-边界元理论对托辊组振动噪声分析与优化的方法。首先,对托辊组进行模态分析与动力学仿真,探明托辊组的振动特性;然后,基于有限元-边界元复合声场仿真方法,作声场的谐响应分析计算托辊组的声场分布,并搭建实际测试平台验证声学仿真模型的可靠性;最后,结合输送能力与轻量化约束条件,得到托辊组结构参数与工作参数的最优解。结果表明,有限元-边界元法可有效模拟托辊组声场分布和变化规律,优化后托辊组噪声声压级较优化前减小约6.1dB,并且托辊组综合性能均有所改善,可对实际工程中的带式输送机优化设计起到有效的指导作用。 展开更多
关键词 托辊组 振动噪声 有限元-边界元 声压级 参数优化
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非圆形隧洞衬砌支护下应力与位移的新解法
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作者 吕爱钟 崔耀启 +1 位作者 蔡辉 马耀财 《工程地质学报》 CSCD 北大核心 2024年第1期206-215,共10页
以往在利用平面弹性复变函数方法进行衬砌支护作用下非圆形隧洞的力学分析时,一般将洞室外域保角映射到象平面的单位圆外域,并认为可以利用同一个映射函数将衬砌截面映射到象平面的圆环域内。当衬砌厚度很薄时,这种方法是可行的,而当衬... 以往在利用平面弹性复变函数方法进行衬砌支护作用下非圆形隧洞的力学分析时,一般将洞室外域保角映射到象平面的单位圆外域,并认为可以利用同一个映射函数将衬砌截面映射到象平面的圆环域内。当衬砌厚度很薄时,这种方法是可行的,而当衬砌相对较厚时,利用同一映射函数所得到的衬砌截面形状发生严重失真。为解决此问题,本文引入两套映射函数,分别将洞室外域映射到象平面的单位圆的圆外域,衬砌截面映射到圆环域。这种方法可以适应于不同的衬砌厚度,利用这种方式获得的衬砌截面,在衬砌较厚时仍能保证衬砌厚度相对均匀。在求解解析函数过程中不再采用传统的幂级数解法,而是使用边界配点法,将两套映射函数结合,获得了该问题的应力解和位移解。本文以马蹄形隧洞为例,求解结果与ANSYS软件所得数值解吻合很好,分析了衬砌厚度对隧洞应力和位移的影响。根据本文解答可以方便、快捷地进行相近条件下隧道的初步设计。 展开更多
关键词 复变函数方法 非圆形压力隧洞 均匀厚度衬砌 两套映射函数 边界配点法
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计及群体压力和群体极化的PDHFSs-TODIM多属性群体决策算法
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作者 袁畅 孙永辉 +2 位作者 王森 武云逸 周伟 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2024年第4期407-417,共11页
在概率对偶犹豫模糊环境下的多属性决策中,针对决策过程一般未考虑决策专家在讨论中所受的群体压力和群体极化的问题,提出了一种计及群体压力和群体极化的概率对偶犹豫模糊集-拓扑判别目标间方法(probabilistic discriminative heteroge... 在概率对偶犹豫模糊环境下的多属性决策中,针对决策过程一般未考虑决策专家在讨论中所受的群体压力和群体极化的问题,提出了一种计及群体压力和群体极化的概率对偶犹豫模糊集-拓扑判别目标间方法(probabilistic discriminative heterogeneous fuzzy sets-topological discriminative inter-objective method,PDHFSsTODIM)的多属性群体决策算法。首先,定义了考虑群体压力的决策信息修正公式,有效削弱群体压力对专家决策信息的影响;然后,搭建了一种考虑群体极化现象的决策模型,该模型充分考虑了专家的主观性,为专家讨论和修正决策提供了机会,通过分配动态决策权重提高决策的置信度,并通过群体极化阈值约束群体的极化效应;进一步,将计算得到的决策数据输入改进的TODIM算法,得到最终决策结果。将算法运用于储能电池综合性能评估分析,通过与其他先进决策算法做对比,验证了所提算法的可靠性与准确性。 展开更多
关键词 概率对偶犹豫模糊集 多属性群体决策 群体压力
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Definition of Measure-theoretic Pressure Using Spanning Sets 被引量:7
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作者 LianFaHE JinFengLV LiNaZHOU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2004年第4期709-718,共10页
We introduce a new definition of measure-theoretic pressure for ergodic measures of con- tinuous maps on a compact metric space.This definition is similar to those of topological pressure involving spanning sets.As an... We introduce a new definition of measure-theoretic pressure for ergodic measures of con- tinuous maps on a compact metric space.This definition is similar to those of topological pressure involving spanning sets.As an application,for C^(1+α)(α>0)diffeomorphisms of a compact manifold, we study the relationship between the measure-theoretic pressure and the periodic points. 展开更多
关键词 Ergodic measure Measure-theoretic pressure Spanning set
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先导式安全阀整定压力预测方法研究
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作者 袁晟毅 尹婷婷 +6 位作者 郭永正 郭松 张中标 田孝帅 王宇翔 罗世洪 张冬林 《机械管理开发》 2024年第6期5-7,10,共4页
以自主研制的先导式安全阀为研究对象,针对先导阀的感压控制结构,开展整定压力预测方法研究。根据动作功能和结构原理分析,提出了一种测量整定预紧力的方式,并研制了专用传感器。对样机进行适应性改造和传感器安装后,开展相关冷态实验... 以自主研制的先导式安全阀为研究对象,针对先导阀的感压控制结构,开展整定压力预测方法研究。根据动作功能和结构原理分析,提出了一种测量整定预紧力的方式,并研制了专用传感器。对样机进行适应性改造和传感器安装后,开展相关冷态实验研究。结果表明,关键力值的监测数据可用于安全阀整定压力的预测,但还需进一步考虑温度等运行参数和阀门结构设计参数的影响,优化预测算法。 展开更多
关键词 先导式安全阀 整定压力 预测方法
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On the variational principle for the topological pressure for certain non-compact sets 被引量:2
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作者 PEI Yu 1 & CHEN ErCai 1,2,1 Department of Mathematics,Nanjing Normal University,Nanjing 210097,China 2 Center for Nonlinear Science,Nanjing University,Nanjing 210093,China 《Science China Mathematics》 SCIE 2010年第4期1117-1128,共12页
Let (X,d,T) be a dynamical system,where (X,d) is a compact metric space and T:X → X is a continuous map.We assume that the dynamical system satisfies g-almost product property and the uniform separation property.We c... Let (X,d,T) be a dynamical system,where (X,d) is a compact metric space and T:X → X is a continuous map.We assume that the dynamical system satisfies g-almost product property and the uniform separation property.We compute the topological pressure of saturated sets under these two conditions.If the uniform separation property does not hold,we compute the topological pressure of the set of generic points.We give an application of these results to multifractal analysis and finally get a conditional variational principle. 展开更多
关键词 uniform separation PROPERTY g-almost product PROPERTY topological pressure of non-compact sets VARIATIONAL principle BS-dinmension
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Level Set Based on Signed Pressure Force Function and Its Application in Liver Image Segmentation 被引量:1
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作者 JIANG Huiyan1,2,FENG Ruijie2,3,GAO Xihe1,2 1.Software College,Northeastern University,Shenyang 110819,Liaoning,China 2.Key Laboratory of Medical Image Computing of Ministry of Education Northeastern University,Shenyang 110819,Liaoning,China 3.Sino-Dutch Biomedical and Information Engineering School,Northeastern University,Shenyang 110819,Liaoning,China 《Wuhan University Journal of Natural Sciences》 CAS 2011年第3期265-270,共6页
The edge-based level set model gives no satisfactory results for images with weak edge, and the region-based model performs poorly for intensity inhomogeneity images. In this paper, we propose an improved region-based... The edge-based level set model gives no satisfactory results for images with weak edge, and the region-based model performs poorly for intensity inhomogeneity images. In this paper, we propose an improved region-based level set model that integrates both the gradient information and the region information. The proposed model defines a novel external energy term, which consists of gradient information and signed pressure forces function. In order to eliminate the re-initialization procedure of traditional level set model, an internal energy term is also introduced for the level set function to maintain signed distance function. Compared with traditional models, our model is more robust against images with weak edge and intensity inhomogeneity. Experiments on liver segmentation from abdominal CT images demonstrate the effectiveness and accuracy of the proposed method. 展开更多
关键词 SEGMENTATION level set signed pressure force LIVER
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大型燃煤火力发电机组调峰优化控制技术 被引量:2
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作者 李阳 周迎迎 《节能技术》 CAS 2024年第1期77-81,92,共6页
调峰优化控制可以使得电网的源荷供需处于平衡状态,对提高火力发电机组调峰的稳定性至关重要。为此,提出一种大型燃煤火力发电机组调峰优化控制技术。构建爬坡压力缓解的目标函数,通过对火电机组、失负荷、储能以及光伏发电进行约束,以... 调峰优化控制可以使得电网的源荷供需处于平衡状态,对提高火力发电机组调峰的稳定性至关重要。为此,提出一种大型燃煤火力发电机组调峰优化控制技术。构建爬坡压力缓解的目标函数,通过对火电机组、失负荷、储能以及光伏发电进行约束,以缓解爬坡压力。构建火力发电机组调峰优化控制的目标函数,结合火力发电机组在运行功率、功率平衡、启停机时间等方面的约束,实现了大型燃煤火力发电机组的调峰优化控制。实验结果表明,文中技术能够缓解大型燃煤火力发电机组的爬坡压力,优化了响应速度。通过所提技术的调峰优化实现了火力发电稳定运行,顺利完成调峰任务。 展开更多
关键词 火力发电机组 源荷平衡 爬坡压力 优化控制 燃煤机组 调峰优化
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热电厂中压蒸汽对定形机的加热及保温层的计算
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作者 汪琦 张慧芬 +1 位作者 俞红啸 汪育佑 《染整技术》 CAS 2024年第1期60-63,共4页
讨论了热电厂使用的循环流化床锅炉结构型式。热电厂输送的中压中温蒸汽经过温度压力控制装置产生饱和蒸汽用于定形机。研究了蒸汽管道保温材料和蒸汽管道保温层厚度计算方法以及施工注意事项。
关键词 热电厂 中压蒸汽 保温 定形机
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水力压裂钻孔抗高压封孔材料研发及带压封堵特征研究
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作者 王蔚鸣 张超 《煤矿安全》 CAS 北大核心 2024年第8期8-15,共8页
为解决因封孔质量不达标导致的水力压裂卸压增透技术在井下现场应用的难题,在总结国内外抗高压封孔材料及封孔方法的基础上,通过系统性基础实验,探究了普通水泥添加特种复合水泥、膨胀剂和减水剂等辅助材料对抗高压封孔材料的凝结时间... 为解决因封孔质量不达标导致的水力压裂卸压增透技术在井下现场应用的难题,在总结国内外抗高压封孔材料及封孔方法的基础上,通过系统性基础实验,探究了普通水泥添加特种复合水泥、膨胀剂和减水剂等辅助材料对抗高压封孔材料的凝结时间、流动性、抗压强度以及膨胀倍率等基础性能的影响规律。研究表明:抗高压封控材料最佳水灰比为0.5,特种复合水泥添加量为20%~25%,复合膨胀剂添加量为4%,萘系减水剂添加量为1.6%时,抗高压封孔材料在保障流动度及膨胀倍率前提下呈现早强高强特性。为验证新材料性能,在龙煤集团平岗煤矿进行现场工业性试验,其凝固时间及抗压强度等参数均达到性能要求。 展开更多
关键词 抗高压封孔材料 水力压裂 凝结时间 流动性 抗压强度
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