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关键词

原位统计分布分析 3

统计偏析度 2

统计符合度 2

X射线阻射性 1

三流体喷嘴喷雾干燥技术 1

交流位置伺服系统 1

交流永磁同步电机；滑模控制器；扩张状态观测器；鲁棒控制；运动控制 1

信号重建 1

分布特征 1

原位统计分布分析表征技术 1

发展地位 1

地下长通道 1

均匀度 1

多功能团簇体填料 1

大口径望远镜；定量反馈理论；主镜位置控制系统；微米级位置控制能力；系统辨识；鲁棒稳定性 1

夹杂 1

夹杂物 1

形状误差 1

抗菌性能 1

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Experimental and CFD analysis of nozzle position of subsonic ejector

Xilai ZHANG, Shiping JIN, Suyi HUANG, Guoqing TIAN

《能源前沿（英文）》 2009年第3卷第2期页码 167-174 doi: 10.1007/s11708-009-0001-5

摘要： The influence of nozzle position on the performance of an ejector was analyzed qualitatively with free jet flow model. Experimental investigations and computational fluid dynamics (CFD) analysis of the nozzle position of the subsonic ejector were also conducted. The results show that there is an optimum nozzle position for the ejector. The ejecting coefficient reaches its maximum when the nozzle is positioned at the optimum and decreases when deviating. Moreover, the nozzle position of an ejector is not a fixed value, but is influenced greatly by the flow parameters. Considering the complexity of the ejector, CFD is reckoned as a useful tool in the design of ejectors.

关键词： ejector nozzle position ejecting coefficient CFD

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Piezoelectric diffuser/nozzle micropump with double pump chambers

WANG Wei, ZHANG Ying, TIAN Li, CHEN Xiaojie, LIU Xiaowei

《机械工程前沿（英文）》 2008年第3卷第4期页码 449-453 doi: 10.1007/s11465-008-0076-4

摘要： To eliminate check valve fatigue and valve clogging, diffuser/nozzle elements are used for flow rectification in a valveless diffuser/nozzle micropump instead of valves. However, the application of this type of micropump is restricted because of its pulsating or periodic flow and low pump flux. In this paper, a diffuser/nozzle Si/Glass micropump with two pump chambers by IC and MEMS technology is designed. The fabrication process requires only one mask and one etch step, so that the fabrication has the advantages of low cost, short processing period, and facilitation of miniaturization. The pump is equipped with a glass cover board so as to conveniently observe the flow status. Pump-chambers and diffuser elements are fabricated by the anisotropic KOH-etch technique on the silicone substrate, and the convex corner is designed to compensate for an anisotropic etch. The driving force of the micropump is produced by the PZT piezoelectric actuator. The pump performance with both actuators actuated in anti- or same-phase mode is also researched. The result indicates that the micropump achieves great performance with the actuators working at anti-phase. This may be because the liquid flows steadily, pulse phenomenon is very weak, and the optimal working frequency, pump back pressure, and flow rate are both double that of the pump driven in same-phase.

关键词： diffuser/nozzle Si/Glass phenomenon rectification diffuser/nozzle micropump frequency

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Depth of cut models for multipass abrasive waterjet cutting of alumina ceramics with nozzle oscillation

Jun WANG

《机械工程前沿（英文）》 2010年第5卷第1期页码 19-32 doi: 10.1007/s11465-009-0082-1

摘要： An experimental study of the depth of cut in multipass abrasive waterjet (AWJ) cutting of alumina ceramics with controlled nozzle oscillation is presented. It is found that this cutting technique can significantly increase the depth of cut by an average of 50.8% as compared to single pass cutting without nozzle oscillation under the corresponding cutting conditions and within the same cutting time. Predictive models for the depth of cut are then developed. The modelling process starts with single pass cutting using a dimensional analysis technique and the particle erosion theories applied to alumina ceramics, before progressing to the development of the models for multipass cutting. The models are finally assessed both qualitatively and quantitatively with experimental data. It is shown that the model predictions are in good agreement with the experimental data with the average deviations of about 1%.

关键词： abrasive waterjet engineering ceramics depth of cut cutting performance nozzle oscillation machining

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Influence of nozzle height to width ratio on ignition and NO

Liutao SUN, Yonghong YAN, Rui SUN, Zhengkang PENG, Chunli XING, Jiangquan WU

《能源前沿（英文）》 2021年第15卷第2期页码 431-448 doi: 10.1007/s11708-021-0726-3

摘要： To improve the ignition behavior and to reduce the high NO emissions of blended pulverized fuels (PF) of semicoke (SC), large-scale experiments were conducted in a 300 kW fired furnace at various nozzle settings, i.e., ratios (denoted by / ) of the height of the rectangular burner nozzle to its width of 1.65, 2.32, and 3.22. The combustion tests indicate that the flame stability, ignition performance, and fuel burnout ratio were significantly improved at a nozzle setting of / = 2.32. The smaller / delayed ignition and caused the flame to concentrate excessively on the axis of the furnace, while the larger / easily caused the deflection of the pulverized coal flame, and a high-temperature flame zone emerged close to the furnace wall. NO emissions at the outlet of the primary zone decreased from 447 to 354 mg/m (O = 6%), and the ignition distance decreased from 420 to 246 mm when the / varied from 1.65 to 3.22. Furthermore, the ratio (denoted by / ) of the strong reduction zone area to the combustion reaction zone area was defined experimentally by the CO concentration to evaluate the reduction zone. The / rose monotonously, but its restraining effects on NO formation decreased as / increased. The results suggested that in a test furnace, regulating the nozzle / conditions sharply reduces NO emissions and improves the combustion efficiency of SC blends possessing an appropriate jet rigidity.

关键词： rectangular jet burner nozzle height to width ratio ignition characteristics pyrolyzed semicoke (SC) and bituminous blend NO_x formation

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Robust energy-efficient train speed profile optimization in a scenario-based position–time–speed network

《工程管理前沿（英文）》 2021年第8卷第4期页码 595-614 doi: 10.1007/s42524-021-0173-1

摘要： Train speed profile optimization is an efficient approach to reducing energy consumption in urban rail transit systems. Different from most existing studies that assume deterministic parameters as model inputs, this paper proposes a robust energy-efficient train speed profile optimization approach by considering the uncertainty of train modeling parameters. Specifically, we first construct a scenario-based position–time–speed (PTS) network by considering resistance parameters as discrete scenario-based random variables. Then, a percentile reliability model is proposed to generate a robust train speed profile, by which the scenario-based energy consumption is less than the model objective value at

α

confidence level. To solve the model efficiently, we present several algorithms to eliminate the infeasible nodes and arcs in the PTS network and propose a model reformulation strategy to transform the original model into an equivalent linear programming model. Lastly, on the basis of our field test data collected in Beijing metro Yizhuang line, a series of experiments are conducted to verify the effectiveness of the model and analyze the influences of parameter uncertainties on the generated train speed profile.

关键词： robust train speed profile percentile reliability model scenario-based position–time–speed network mixed-integer programming

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Strategic position and development prospects of nuclear energy in China

SHEN Wenquan

《能源前沿（英文）》 2007年第1卷第2期页码 125-128 doi: 10.1007/s11708-007-0015-9

摘要： By analyzing the challenges of China s energy supply, an excellent perspective of nuclear power development in the country has been described. Taking into account the near-, mid-, and long-term development requirements, a comprehensive, coordinated and sustainable nuclear power program is proposed. Thus, our national nuclear industry can not only catch up with the world s advanced level in proper time, but also possess enough stamina for sustainability.

关键词： development excellent perspective long-term development comprehensive national

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Air-bearing position optimization based on dynamic characteristics of ultra-precision linear stages

CHEN Xuedong, LI Zhixin

《机械工程前沿（英文）》 2008年第3卷第4期页码 400-407 doi: 10.1007/s11465-008-0060-z

摘要： Air-bearings are installed between the stator and the mover of ultra-precision linear stages to suppress vibration and mechanical contact. Spring-damping elements are used to emulate the complex interaction of the finite element model (FEM) developed in this paper and the system dynamic behaviors are analyzed. Through the experimental modal test, the validity and reliability of the model are proven. However, the dynamic characteristics including mode frequency, mode shape, and response amplitude are obviously changed with the position of air-bearings. The combined optimization method is used to optimize the air-bearings position. The best and worst positions are obtained using the dynamic characteristic analysis. The method can be generalized to the connection position of different components in manufacture elements and to implement the system dynamic characteristics optimization when the connection position can be changed.

关键词： manufacture different interaction air-bearings response amplitude

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Task-space position/attitude tracking control of FAST fine tuning system

QI Lin, ZHANG Hui, DUAN Guanghong

《机械工程前沿（英文）》 2008年第3卷第4期页码 392-399 doi: 10.1007/s11465-008-0056-8

摘要： This paper addresses the task-space position/attitude tracking control of a suspended parallel robot, which is being developed in the framework of a five-hundred meter aperture spherical radio telescope (FAST) project. Based on the quaternion algebra, a novel model-independent task-space PD controller that ensures end-effector position and attitude tracking is presented. The simulation and experimental results show that the new controller has better control effects than the traditional joint-space controller.

关键词： telescope five-hundred end-effector controller simulation

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我国致密砂岩气资源潜力、分布与未来发展地位

张国生,邓松涛

《中国工程科学》 2012年第14卷第6期页码 87-93

摘要：

系统分析了我国鄂尔多斯、四川和塔里木等主要盆地致密砂岩气成藏条件和主控因素，提出斜坡岩性型和深层构造型是两种最重要的致密砂岩气藏。采用多因素叠合法预测有利含气范围，并通过对已知重点致密砂岩气田的解剖研究，刻度出储量丰度、含气面积系数等关键参数，采用类比法来计算主要盆地的致密砂岩气资源量。研究表明，我国致密砂岩气技术可采资源量为9.2万亿～13.4万亿m³，主要分布于含煤系地层的盆地中；致密砂岩气资源开发利用现实性最好，在国家政策扶持和工程技术进步的推动下，再经过10～20年的发展，有望成为我国天然气开发利用的主导资源之一。

关键词：致密砂岩气分布特征资源潜力发展地位

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适用于混合动力汽车的表贴式永磁同步电机初始位置估算 Article

Bing TIAN,Qun-tao AN,Li SUN,Dong-yang SUN,Jian-dong DUAN

《信息与电子工程前沿（英文）》 2016年第17卷第8期页码 803-813 doi: 10.1631/FITEE.1500298

摘要：霍尔开关位置传感器初始位置测量精度为±30度，使得永磁同步电机在汽车启动阶段提供的最大电磁转矩受到限制。因此，对表贴式永磁同步电机非线性（磁饱和）模型进行了研究，并依据非线性模型进行较准确的初始位置估算。本文采用混合注入法（注入高频电压矢量和直流电压矢量）估算转子位置，其中直流电压用于改变铁芯饱和度，而铁芯饱和度又将调制高频电流响应。结合一种特殊的解调算法便可从高频电流响应中获得磁饱和特征函数以及转子位置信息。通过MATLAB/simulink和实验进行了转子位置估算。

关键词：表贴式永磁同步电机；初始位置估算；非线性模型；混合注入法；位置观测器

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Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

《机械工程前沿（英文）》 2013年第8卷第1期页码 80-87 doi: 10.1007/s11465-013-0362-7

摘要：

In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

关键词： gear planetary epicyclic transmission load sharing transmission error

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Insult of gastroesophageal reflux on airway: clinical significance of pharyngeal nozzle

null

《医学前沿（英文）》 2015年第9卷第1期页码 117-122 doi: 10.1007/s11684-014-0343-1

摘要：

At the very time of global paying the highest attention to the worst insults of smoking as well as haze on the airway, everybody knows both are exogenous and noticeable. However, people mostly, including many medical personnel, do not know how badly the gastroesophageal reflux (GER) insults on our own airway. Symptoms of GER are commonly seen as heartburn and regurgitation, which can be mostly tolerated. However, when the up going gastric content reversely passes the esophagus and then the distal pharynx, where it appears a beak like stricture, serving as a nozzle, so as to produce numerous micro-particles and reach the oro-nasal cavity and also the airway causing allergic rhinitis and asthmatic attacks, even pulmonary parenchyma lesions. It will reduce life quality or even jeopardize life. The point that the endogenous insult appears in the respiratory system, but originates from the digestive tract is not well known and often undiagnosed and not correctly treated. The GER induced airway challenge is a treatable and preventive entity, as soon as a diagnosis is made, a good relief could be expected by means of life style adjustment, medicine, or fixation of the patulous cardia through radiofrequency or fundoplication. The author Dr. Zhonggao Wang had suffered it for long and symptoms disappeared for 8 years after anti-reflux surgery. Here is a presentation of Dr. Zhonggao Wang and his team’s work and would call attention to the public so as to recognize this relatively unknown entity — a treatable condition occurring from human itself, but not from outside surroundings as smoking or haze does.

关键词： gastroesophageal reflux airway pharyngeal nozzle micro-aspiration asthma

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我国非常规天然气开发利用前景与战略地位

“能源领域咨询研究”综合组

《中国工程科学》 2015年第17卷第9期页码 6-10

摘要：

我国非常规天然气资源比较丰富，开发利用程度低，且有后发优势，加快非常规天然气资源开发利用对我国经济社会发展与能源安全具有重要战略意义。本文在客观评价四类非常规天然气资源潜力与开发趋势的基础上，提出了我国非常规天然气开发利用战略和措施建议。研究认为，我国页岩气、致密砂岩气和煤层气可采资源总量约为3.1×1013 m3，大约是常规天然气可采资源量的1.5倍，技术进步和国家政策扶持是实现非常规天然气资源大规模开发利用的关键。我国非常规天然气开发利用可采取“三步走”的路线，积极组织，加快发展，预计到2020年前后，我国非常规天然气产量将与常规天然气平分秋色，2030年前后非常规天然气产量有望达到3×1011 m3，约占总产量的2/3，非常规天然气将成为保障我国天然气工业长期稳定和健康发展的主体资源。

关键词：非常规天然气；资源潜力；开发利用；战略地位

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地下长通道补气口位置对火灾机械排烟效率的影响

胡隆华,霍然,李元洲,易亮,王浩波

《中国工程科学》 2005年第7卷第5期页码 90-92

摘要：

在地下长通道内开展了针对一组相对位置不同的补气口—排烟口的排烟效果的全尺寸对比试验。结果表明，在地下长通道内设置的补气口—排烟口在针对发生火灾情况的优化组合上，应尽量遵循“远端补气、近端排烟”的原则。

关键词：地下长通道补气口排烟口机械排烟效率火灾

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连铸钢坯质量的原位统计分布分析研究

王海舟,李美玲,陈吉文,吴超

《中国工程科学》 2003年第5卷第10期页码 34-42

摘要：

采用原位统计分布分析技术得到与样品原位置相对应的数以万计原始信号并对其进行系统解析，实现不同质量连铸钢坯试样的疏松度、均匀度以及夹杂物含量的定量表征。准确计算了连铸钢坯试样疏松度、碳元素的最大偏析度。提出铸坯各原位置成分含量的权重比率方法用以表征材料的均匀度，并提供了统计分布允许差范围内（C₀±R）所占权重比率以及权重比率为95%置信度时，中位值置信扩展率（K）等2种判断模式。该方法以测量信息的原始性、原位性及统计性为特征，反映了连铸钢坯较大尺度范围内各化学组成及其形态的定量统计分布规律。采用上述方法可以合理解释连铸钢坯之间的质量差异性，可作为连铸钢坯质量的判断依据。

关键词：原位统计分布分析连铸钢坯疏松度均匀度夹杂物