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Analysis and characterization of wind-solar-constant torque spring hybridized model

Shantanu ACHARYA,Subhadeep BHATTACHARJEE

《能源前沿（英文）》 2014年 第8卷 第3期   页码 279-289 doi: 10.1007/s11708-014-0312-z

摘要： Solar and wind are the most promising renewable energy resources. But their unpredictable and varying nature prevents them from being used as the sole resource for power generation. This paper presents a model of wind and solar thermal hybrid power plant with a spring storage system which is expected to play an efficient role in combating with the drawbacks related to renewable power generation. In the proposed scheme, wind energy is harnessed by a hybrid vertical axis wind turbine, solar energy is utilized by a Stirling engine, and the surplus energy is stored in a winding spring. The paper discusses the working methodologies and analyses the performance of such 2.6 kW hybrid power plant model. It has been observed that the plant is capable of consistently generating 50% of its rated capacity irrespective of limitations in solar and wind resources.

关键词： hybrid vertical axis wind turbine     Stirling engine     solar-thermal energy     wind energy     constant torque spring    

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Back to the spring of Wuhan: facts and hope of COVID-19 outbreak

Guangbiao Zhou, Saijuan Chen, Zhu Chen

《医学前沿（英文）》 2020年 第14卷 第2期   页码 113-116 doi: 10.1007/s11684-020-0758-9

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Static balancing of planar articulated robots

Giuseppe QUAGLIA,Zhe YIN

《机械工程前沿（英文）》 2015年 第10卷 第4期   页码 326-343 doi: 10.1007/s11465-015-0355-9

摘要：

Static balancing for a manipulator’s weight is necessary in terms of energy saving and performance improvement. This paper proposes a method to design balancing devices for articulated robots in industry, based on robotic dynamics. Full design details for the balancing system using springs are presented from two aspects: One is the optimization for the position of the balancing system; the other is the design of the spring parameters. As examples, two feasible balancing devices are proposed, based on different robotic structures: The first solution consists of linkages and springs; the other consists of pulleys, cross mechanisms and (hydro-) pneumatic springs. Then the two solutions are compared. Pneumatic, hydro-pneumatic and mechanical springs are discussed and their parameters are decided according to the requirements of torque compensation. Numerical results show that with the proper design using the methodology presented in this paper, an articulated robot can be statically balanced perfectly in all configurations. This paper therefore provides a design method of the balancing system for other similar structures.

关键词： robotics     static balancing     pneumatic spring     mechanical spring     torque compensation    

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A perspective of “Nuclear Hot Spring” for long-term sustainable economy of the world

Yingzhong LU

《能源前沿（英文）》 2011年 第5卷 第4期   页码 349-357 doi: 10.1007/s11708-011-0168-4

摘要： The rapid growth of human economy in the late 20th century gave rise to great concern over sustainability of the world. A pessimistic “Full World Model” forecasts that human economy could not develop further. The nuclear fission (and fusion later), however, could release huge amount of energy to create sufficient useful material resources and turn the said pessimistic modelinto a new optimistic “Sustainable World Model”.The dilemma of nuclear energy (Military Giant vs. Civil Dwarf) jeopardizes its performance as a “Technologic Fixer”. According to Mother Nature’s teachings, the elimination of the root-causes of the design-based risk factors could solve this problem. Recent technology break-through from inherent safety to natural safety has been made in China. The proposed full-power natural circulation “Nuclear Hot Spring (NHS)” reactor could operate solely on natural forces without complex man-made coolant circulation equipment and human-operated control systems. The cheap, unlimited supply of energy from nuclear energy could change the geopolitics forever, and finally eliminate the root-causes of most international and regional conflicts.

关键词： natural safety reactor     full power natural circulation     sustainable world economy    

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Spectral reflectance indices as proxies for yield potential and heat stress tolerance in spring wheat

Caiyun LIU, Francisco PINTO, C. Mariano COSSANI, Sivakumar SUKUMARAN, Matthew P. REYNOLDS

《农业科学与工程前沿（英文）》 2019年 第6卷 第3期   页码 296-308 doi: 10.15302/J-FASE-2019269

摘要：

The application of spectral reflectance indices (SRIs) as proxies to screen for yield potential (YP) and heat stress (HS) is emerging in crop breeding programs. Thus, a comparison of SRIs and their associations with grain yield (GY) under YP and HS conditions is important. In this study, we assessed the usefulness of 27 SRIs for indirect selection for agronomic traits by evaluating an elite spring wheat association mapping initiative (WAMI) population comprising 287 elite lines under YP and HS conditions. Genetic and phenotypic analysis identified 11 and 9 SRIs in different developmental stages as efficient indirect selection indices for yield in YP and HS conditions, respectively. We identified enhanced vegetation index (EVI) as the common SRI associated with GY under YP at booting, heading and late heading stages, whereas photochemical reflectance index (PRI) and normalized difference vegetation index (NDVI) were the common SRIs under booting and heading stages in HS. Genome-wide association study (GWAS) using 18704 single nucleotide polymorphisms (SNPs) from Illumina iSelect 90K identified 280 and 43 marker-trait associations for efficient SRIs at different developmental stages under YP and HS, respectively. Common genomic regions for multiple SRIs were identified in 14 regions in 9 chromosomes: 1B (60–62 cM), 3A (15, 85–90, 101–105 cM), 3B (132–134 cM), 4A (47–51 cM), 4B (71–75 cM), 5A (43–49, 56–60, 89–93 cM), 5B (124–125 cM), 6A (80–85 cM), and 6B (57–59, 71 cM). Among them, SNPs in chromosome 5A (89–93 cM) and 6A (80–85 cM) were co-located for yield and yield related traits. Overall, this study highlights the utility of SRIs as proxies for GY under YP and HS. High heritability estimates and identification of marker-trait associations indicate that SRIs are useful tools for understanding the genetic basis of agronomic and physiological traits.

关键词： genome-wide association study (GWAS)     heat tolerance     spectral reflectance     spring wheat    

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Host protection against Omicron BA.2.2 sublineages by prior vaccination in spring 2022 COVID-19 outbreak

《医学前沿（英文）》 2023年 第17卷 第3期   页码 562-575 doi: 10.1007/s11684-022-0977-3

摘要： The Omicron family of SARS-CoV-2 variants are currently driving the COVID-19 pandemic. Here we analyzed the clinical laboratory test results of 9911 Omicron BA.2.2 sublineages-infected symptomatic patients without earlier infection histories during a SARS-CoV-2 outbreak in Shanghai in spring 2022. Compared to an earlier patient cohort infected by SARS-CoV-2 prototype strains in 2020, BA.2.2 infection led to distinct fluctuations of pathophysiological markers in the peripheral blood. In particular, severe/critical cases of COVID-19 post BA.2.2 infection were associated with less pro-inflammatory macrophage activation and stronger interferon alpha response in the bronchoalveolar microenvironment. Importantly, the abnormal biomarkers were significantly subdued in individuals who had been immunized by 2 or 3 doses of SARS-CoV-2 prototype-inactivated vaccines, supporting the estimation of an overall 96.02% of protection rate against severe/critical disease in the 4854 cases in our BA.2.2 patient cohort with traceable vaccination records. Furthermore, even though age was a critical risk factor of the severity of COVID-19 post BA.2.2 infection, vaccination-elicited protection against severe/critical COVID-19 reached 90.15% in patients aged ≥ 60 years old. Together, our study delineates the pathophysiological features of Omicron BA.2.2 sublineages and demonstrates significant protection conferred by prior prototype-based inactivated vaccines.

关键词： SARS-CoV-2     COVID-19     host response     bronchoalveolar lavage fluid (BALF)    

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Comparative proteomic analysis of cold responsive proteins in two wheat cultivars with different tolerance to spring

Shujuan ZHANG,Guoqi SONG,Yulian LI,Jie GAO,Jiao WANG,Guiju CHEN,Haosheng LI,Genying LI,Zhendong ZHAO

《农业科学与工程前沿（英文）》 2014年 第1卷 第1期   页码 37-45 doi: 10.15302/J-FASE-2014008

摘要： Spring radiation frost (SRF) is a severe environmental stress which impairs wheat yield and productivity worldwide. To better understand the mechanism of wheat ( ) responding to SRF, a comparative proteomic analysis was performed to analyze the changes of the key proteins in two wheat cultivars Jimai22 and Luyuan301 with high and low tolerance to SRF respectively. A total of 43 differentially expressed proteins (DEPs) which mainly involved in carbohydrate metabolism, amino acid metabolism, resistance proteins and antioxidant enzymes, photosynthesis and cellular respiration proteins, cell-wall related proteins, protein translation/processing/degradation and signal transduction were isolated and identified by two-dimensional electrophoresis and MALDI-TOF-TOF MS. The results revealed that of the 21 DEPs in Jimai22 responding to the SRF, 13 DEPs were upregulated and 8 DEPs were downregulated, and that of the 22 DEPs in Luyuan301, 9 DEPs were upregulated and 13 DEPs were downregulated. These DEPs might be responsible for the stronger cold resistance of Jimai22 compared to Luyuan301. The expression pattern and function analysis of these DEPs were very significant to understanding the mechanism of the SRF responses in wheat.

关键词： common wheat     spring radiation frost     proteomic analysis     2-DE     MALDI-TOF-TOF MS    

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螺旋管簧的可靠性优化设计

张义民,贺向东,闻邦椿

《中国工程科学》 2002年 第4卷 第5期   页码 71-74

摘要：

讨论了螺旋管簧的可靠性优化设计问题。在基本随机变量的概率特性已知的情况下，采用二阶矩法和可靠性优化设计方法对螺旋管簧进行了可靠性优化设计，通过计算机程序可以直接实现螺旋管簧的可靠性优化设计，迅速准确地得到螺旋管簧的可靠性优化设计信息。

关键词： 螺旋管簧     可靠性     优化设计     二阶矩技术    

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不完全概率信息的车辆常用弹簧的可靠性灵敏度设计

张义民,刘巧伶,闻邦椿

《中国工程科学》 2004年 第6卷 第1期   页码 74-80

摘要：

将可靠性设计理论与灵敏度分析方法相结合，讨论了车辆常用弹簧的可靠性灵敏度设计问题，提出了可靠性灵敏度设计的计算方法，给出了可靠性灵敏度的变化规律，研究了设计参数的改变对车辆常用弹簧可靠性的影响，为车辆常用弹簧的可靠性设计提供了理论依据。

关键词： 车辆常用弹簧     可靠性设计     灵敏度     任意分布参数    

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Analysis of the dynamic hysteresis characteristic of finger seal

LEI Yanni, CHEN Guoding

《机械工程前沿（英文）》 2007年 第2卷 第1期   页码 32-36 doi: 10.1007/s11465-007-0005-y

摘要： The research about hysteresis characteristic of finger seal (FS), which was carried out based on the model with static loads, could not reflect the dynamics behavior of FS system when the rotor runs at high speed. To solve this problem, the relations between the dynamics parameters, structure parameters as well as working parameters in the system were given out through the analysis of finite element analysis result. A mass spring damper dynamics model of FS system was proposed and the hysteresis characteristic of the FS system was analyzed. This work shows that the dynamics characteristic analysis of the FS is necessary and the dynamics model proposed in this paper is valid. This dynamics model is the basis for the optimization design of FS system.

关键词： FS     necessary     hysteresis characteristic     optimization     spring    

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硅微z轴谐振陀螺仪负电刚度效应分析及实验验证

夏敦柱,周百令,王寿荣

《中国工程科学》 2007年 第9卷 第8期   页码 66-68

摘要：

介绍了在开环工作状态下硅微z轴谐振陀螺仪由于加工工艺缺陷所导致的误差机理。为减小陀螺仪初始电容差和抑制正交耦合误差，提出了一种闭环控制检测策略。重点分析了其力矩反馈器的电刚度效应并给出其线性数学模型表示式。通过对硅微z轴陀螺仪敏感模态的反馈力与谐振频率的关系分析，间接得出了在敏感方向上电负刚度与力矩器所施电压的内在联系，并在实验上进一步验证电刚度效应。这将为下一步闭环控制方案的设计奠定重要基础。

关键词： 硅微z轴陀螺仪     负电刚度     力矩反馈器     微机电系统    

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New nonlinear stiffness actuator with predefined torque‒deflection profile

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0721-3

摘要： A nonlinear stiffness actuator (NSA) could achieve high torque/force resolution in low stiffness range and high bandwidth in high stiffness range, both of which are beneficial for physical interaction between a robot and the environment. Currently, most of NSAs are complex and hardly used for engineering. In this paper, oriented to engineering applications, a new simple NSA was proposed, mainly including leaf springs and especially designed cams, which could perform a predefined relationship between torque and deflection. The new NSA has a compact structure, and it is lightweight, both of which are also beneficial for its practical application. An analytical methodology that maps the predefined relationship between torque and deflection to the profile of the cam was developed. The optimal parameters of the structure were given by analyzing the weight of the NSA and the mechanic characteristic of the leaf spring. Though sliding friction force is inevitable because no rollers were used in the cam-based mechanism, the sliding displacement between the cam and the leaf spring is very small, and consumption of sliding friction force is very low. Simulations of different torque‒deflection profiles were carried out to verify the accuracy and applicability of performing predefined torque‒deflection profiles. Three kinds of prototype experiments, including verification experiment of the predefined torque‒deflection profile, torque tracking experiment, and position tracking experiment under different loads, were conducted. The results prove the accuracy of performing the predefined torque‒deflection profile, the tracking performance, and the interactive performance of the new NSA.

关键词： compliant actuator     nonlinear stiffness actuator     nonlinear spring     predefined torque−deflection profile    

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Study of an artificial boundary condition based on the damping-solvent extraction method

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第3期   页码 281-287 doi: 10.1007/s11709-012-0167-5

摘要： A new artificial boundary condition for time domain analysis of a structure-unlimited-foundation system was proposed. The boundary condition was based on the damping-solvent extraction method. The principle of the damping-solvent extraction method was described. An artificial boundary condition was then established by setting two spring-damper systems and one artificial damping limited region. A test example was developed to verify that the proposed boundary condition and model had high precision. Compared with the damping-solvent extraction method, this boundary condition is easier to be applied to finite element method (FEM)-based numerical calculations.

关键词： damping-solvent extraction method     structure-unlimited-foundation system     spring-damper system     artificial damping limited region     finite element method    

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Dynamic modeling of hydrostatic guideway considering compressibility and inertia effect

Yikang DU,Kuanmin MAO,Yaming ZHU,Fengyun WANG,Xiaobo MAO,Bin LI

《机械工程前沿（英文）》 2015年 第10卷 第1期   页码 78-88 doi: 10.1007/s11465-015-0331-4

摘要：

Hydrostatic guideways are used as an alternative to contact bearings due to high stiffness and high damping in heavy machine tools. To improve the dynamic characteristic of bearing structure, the dynamic modeling of the hydrostatic guidway should be accurately known. This paper presents a “mass-spring-Maxwell” model considering the effects of inertia, squeeze, compressibility and static bearing. To determine the dynamic model coefficients, numerical simulation of different cases between displacement and dynamic force of oil film are performed with fluent code. Simulation results show that hydrostatic guidway can be taken as a linear system when it is subjected to a small oscillation amplitude. Based on a dynamic model and numerical simulation, every dynamic model’s parameters are calculated by the Levenberg-Marquardt algorithm. Identification results show that “mass-spring-damper” model is the most appropriate dynamic model of the hydrostatic guidway. This paper provides a reference and preparation for the analysis of the dynamic model of the similar hydrostatic bearings.

关键词： hydrostatic guidway     dynamic model     dynamic mesh technique     Levenberg-Marquardt     mass-spring-damper model    

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Concentrations of toxic heavy metals in ambient particulate matter in an industrial area of northeastern China

PIAO Fengyuan, SUN Xiance, LIU Shuang, YAMAUCHI Toru

《医学前沿（英文）》 2008年 第2卷 第2期   页码 207-210 doi: 10.1007/s11684-008-0040-z

摘要： This paper investigates concentrations of various heavy metals in ambient particulate matter (PM) and provide evidence for prevention from air pollution. The concentrations of heavy metal components in the PM were determined by inductively coupled plasma/Mass spectrometry (ICP/MS) from September 2000 to August 2002 in a northeast industrial city in China. Concentrations of Cd, Mn, Pb, Ni, Cr and As in the PM were 9.3, 461.9, 588.7, 69.5, 205.7 and 57.4 ng/m in the industrial area, and 5.7, 245.5, 305.0, 31.4, 58.8 and 32.5 ng/m in the main road, respectively. Concentrations of these heavy metals except Cd were significantly higher in the industrial area and main road than those in the suburban area ( < 0.05 or < 0.01). The change curves of the six heavy metal concentrations show their concentrations increased in the winter and spring, but decreased in the summer and autumn. The results indicate that concentrations of the metals in the PM are relatively high in the industrial area and main road.

关键词： summer     August     northeast industrial     September     spring    

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标题 作者 时间 类型 操作

Analysis and characterization of wind-solar-constant torque spring hybridized model

Shantanu ACHARYA,Subhadeep BHATTACHARJEE

期刊论文

Back to the spring of Wuhan: facts and hope of COVID-19 outbreak

Guangbiao Zhou, Saijuan Chen, Zhu Chen

期刊论文

Static balancing of planar articulated robots

Giuseppe QUAGLIA,Zhe YIN

期刊论文

A perspective of “Nuclear Hot Spring” for long-term sustainable economy of the world

Yingzhong LU

期刊论文

Spectral reflectance indices as proxies for yield potential and heat stress tolerance in spring wheat

Caiyun LIU, Francisco PINTO, C. Mariano COSSANI, Sivakumar SUKUMARAN, Matthew P. REYNOLDS

期刊论文

Host protection against Omicron BA.2.2 sublineages by prior vaccination in spring 2022 COVID-19 outbreak

期刊论文

Comparative proteomic analysis of cold responsive proteins in two wheat cultivars with different tolerance to spring

Shujuan ZHANG,Guoqi SONG,Yulian LI,Jie GAO,Jiao WANG,Guiju CHEN,Haosheng LI,Genying LI,Zhendong ZHAO

期刊论文

螺旋管簧的可靠性优化设计

张义民,贺向东,闻邦椿

期刊论文

不完全概率信息的车辆常用弹簧的可靠性灵敏度设计

张义民,刘巧伶,闻邦椿

期刊论文

Analysis of the dynamic hysteresis characteristic of finger seal

LEI Yanni, CHEN Guoding

期刊论文

硅微z轴谐振陀螺仪负电刚度效应分析及实验验证

夏敦柱,周百令,王寿荣

期刊论文

New nonlinear stiffness actuator with predefined torque‒deflection profile

期刊论文

Study of an artificial boundary condition based on the damping-solvent extraction method

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

期刊论文

Dynamic modeling of hydrostatic guideway considering compressibility and inertia effect

Yikang DU,Kuanmin MAO,Yaming ZHU,Fengyun WANG,Xiaobo MAO,Bin LI

期刊论文

Concentrations of toxic heavy metals in ambient particulate matter in an industrial area of northeastern China

PIAO Fengyuan, SUN Xiance, LIU Shuang, YAMAUCHI Toru

期刊论文