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机电装备的失效分析、安全评定和无损检测

钟群鹏,武淮生,张峥,田永江

《中国工程科学》 1999年 第1卷 第1期   页码 43-48

摘要:

从认识论的高度阐明失效、失效分析和预防在人类科学技术发展中的属性、地位和作用。失效分析和预防具有多学科交叉综合的属性,它的发展依赖于应用学科、应用基础学科、甚至于基础学科的发展,但又对它们的发展起重要反转作用和影响。因此,它是科学技术第一生产力中最积极、最活跃的因素之一。从方法论的角度进一步叙述了失效分析与失效预防之间的辩证关系。失效分析是一种事后的逆向思维过程,它是从异常现象(结果)到因素(模式、原因和机理)的反向科技探索,而失效预防(安全评定)则是从因素到结果的一种事先的正向思维过程。逆向思维与正向思维协同并用,事后分析转化为事先分析,构成科学技术研究活动和科技发展的全过程,两者不可偏废。综述了失效分析和失效预防(安全评定)的主要内容、技术、方法和它们的发展趋势,并提出它们与无损检测技术之间的关系。

关键词: 机电装备     失效分析     安全评定     无损检测    

Mechanical design and analysis of a novel variable stiffness actuator with symmetrical pivot adjustment

《机械工程前沿(英文)》 2021年 第16卷 第4期   页码 711-725 doi: 10.1007/s11465-021-0647-1

摘要: The safety of human–robot interaction is an essential requirement for designing collaborative robotics. Thus, this paper aims to design a novel variable stiffness actuator (VSA) that can provide safer physical human–robot interaction for collaborative robotics. VSA follows the idea of modular design, mainly including a variable stiffness module and a drive module. The variable stiffness module transmits the motion from the drive module in a roundabout manner, making the modularization of VSA possible. As the key component of the variable stiffness module, a stiffness adjustment mechanism with a symmetrical structure is applied to change the positions of a pair of pivots in two levers linearly and simultaneously, which can eliminate the additional bending moment caused by the asymmetric structure. The design of the double-deck grooves in the lever allows the pivot to move freely in the groove, avoiding the geometric constraint between the parts. Consequently, the VSA stiffness can change from zero to infinity as the pivot moves from one end of the groove to the other. To facilitate building a manipulator in the future, an expandable electrical system with a distributed structure is also proposed. Stiffness calibration and control experiments are performed to evaluate the physical performance of the designed VSA. Experiment results show that the VSA stiffness is close to the theoretical design stiffness. Furthermore, the VSA with a proportional–derivative feedback plus feedforward controller exhibits a fast response for stiffness regulation and a good performance for position tracking.

关键词: variable stiffness actuator     variable stiffness module     drive module     symmetrical structure     double-deck grooves     expandable electrical system    

Recycling Materials from Waste Electrical and Electronic Equipment

Jinhui Li

《环境科学与工程前沿(英文)》 2017年 第11卷 第5期 doi: 10.1007/s11783-017-1001-z

EEG-controlled functional electrical stimulation rehabilitation for chronic stroke: system design and

《医学前沿(英文)》 2021年 第15卷 第5期   页码 740-749 doi: 10.1007/s11684-020-0794-5

摘要: Stroke is one of the most serious diseases that threaten human life and health. It is a major cause of death and disability in the clinic. New strategies for motor rehabilitation after stroke are undergoing exploration. We aimed to develop a novel artificial neural rehabilitation system, which integrates brain--computer interface (BCI) and functional electrical stimulation (FES) technologies, for limb motor function recovery after stroke. We conducted clinical trials (including controlled trials) in 32 patients with chronic stroke. Patients were randomly divided into the BCI-FES group and the neuromuscular electrical stimulation (NMES) group. The changes in outcome measures during intervention were compared between groups, and the trends of ERD values based on EEG were analyzed for BCI-FES group. Results showed that the increase in Fugl Meyer Assessment of the Upper Extremity (FMA-UE) and Kendall Manual Muscle Testing (Kendall MMT) scores of the BCI-FES group was significantly higher than that in the sham group, which indicated the practicality and superiority of the BCI-FES system in clinical practice. The change in the laterality coefficient (LC) values based on μ-ERD (ΔLCm-ERD) had high significant positive correlation with the change in FMA-UE(r= 0.6093, P=0.012), which provides theoretical basis for exploring novel objective evaluation methods.

关键词: brain–computer interface     functional electrical stimulation     electroencephalogram     laterality coefficient     chronic stroke    

CHARACTERISTICS OF HERBIVORY/WOUND-ELICITED ELECTRICAL SIGNAL TRANSDUCTION IN TOMATO

《农业科学与工程前沿(英文)》 2021年 第8卷 第2期

摘要:

Electrical signals commonly occur in plants in response to various environmental changes and have a dominant function in plant acclimation. The transduction of wound-elicited electrical signals in the model plant species Arabidopsis has been characterized but the characteristics of electrical signal transduction in response to herbivory or wounding in crop species remain unknown. Here, the features of electrical signals elicited by insect herbivory and wounding in tomato were investigated. Unlike those in Arabidopsis, wounding tomato leaves did not cause leaf-to-leaf electrical signal transduction. In contrast, electrical signals elicited in response to petiole wounding were stronger and more strongly transduced. Leaflet wounding also activated electrical signal transduction and jasmonic acid (JA) signaling within the whole compound leaf. It was also demonstrated that tomato glutamate receptor-like 3.3 (GLR3.3) and GLR3.5 mediated leaflet-to-leaflet electrical signal transduction. Herbivory-induced JA accumulation and Helicoverpa armigera resistance were reduced in glr3.3/3.5 plants. This work reveals the nature of electrical signal transduction in tomato and emphasizes the key roles of GLR3.3 and GLR3.5 in electrical signal transduction and JA signaling activation.

 

关键词: electrical signal / glutamate receptor-like / herbivory / jasmonic acid / tomato    

Engineering Fronts in fields of Energy and Electrical Science and Technologies in the report of

《能源前沿(英文)》 2023年 第17卷 第1期   页码 5-8 doi: 10.1007/s11708-023-0868-6

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Combination of steam-enhanced extraction and electrical resistance heating for efficient remediation

《环境科学与工程前沿(英文)》 2022年 第16卷 第11期 doi: 10.1007/s11783-022-1582-z

摘要:

● Coupling merits of SEE and ERH were explored by a laboratory-scale device.

关键词: Steam-enhanced extraction     Electrical resistance heating     Dense nonaqueous phase liquid     Soil remediation     Energy consumption    

A bionic approach for the mechanical and electrical decoupling of an MEMS capacitive sensor in ultralow

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-023-0747-1

摘要: Capacitive sensors are efficient tools for biophysical force measurement, which is essential for the exploration of cellular behavior. However, attention has been rarely given on the influences of external mechanical and internal electrical interferences on capacitive sensors. In this work, a bionic swallow structure design norm was developed for mechanical decoupling, and the influences of structural parameters on mechanical behavior were fully analyzed and optimized. A bionic feather comb distribution strategy and a portable readout circuit were proposed for eliminating electrostatic interferences. Electrostatic instability was evaluated, and electrostatic decoupling performance was verified on the basis of a novel measurement method utilizing four complementary comb arrays and application-specific integrated circuit readouts. An electrostatic pulling experiment showed that the bionic swallow structure hardly moved by 0.770 nm, and the measurement error was less than 0.009% for the area-variant sensor and 1.118% for the gap-variant sensor, which can be easily compensated in readouts. The proposed sensor also exhibited high resistance against electrostatic rotation, and the resulting measurement error dropped below 0.751%. The rotation interferences were less than 0.330 nm and (1.829 × 10−7)°, which were 35 times smaller than those of the traditional differential one. Based on the proposed bionic decoupling method, the fabricated sensor exhibited overwhelming capacitive sensitivity values of 7.078 and 1.473 pF/µm for gap-variant and area-variant devices, respectively, which were the highest among the current devices. High immunity to mechanical disturbances was maintained simultaneously, i.e., less than 0.369% and 0.058% of the sensor outputs for the gap-variant and area-variant devices, respectively, indicating its great performance improvements over existing devices and feasibility in ultralow biomedical force measurement.

关键词: micro-electro-mechanical system capacitive sensor     bionics     operation instability     mechanical and electrical decoupling     biomedical force measurement    

systematic approach in load disaggregation utilizing a multi-stage classification algorithm for consumer electrical

Chuan Choong YANG, Chit Siang SOH, Vooi Voon YAP

《能源前沿(英文)》 2019年 第13卷 第2期   页码 386-398 doi: 10.1007/s11708-017-0497-z

摘要: The potential to save energy in existing consumer electrical appliances is very high. One of the ways to achieve energy saving and improve energy use awareness is to recognize the energy consumption of individual electrical appliances. To recognize the energy consumption of consumer electrical appliances, the load disaggregation methodology is utilized. Non-intrusive appliance load monitoring (NIALM) is a load disaggregation methodology that disaggregates the sum of power consumption in a single point into the power consumption of individual electrical appliances. In this study, load disaggregation is performed through voltage and current waveform, known as the - trajectory. The classification algorithm performs cropping and image pyramid reduction of the - trajectory plot template images before utilizing the principal component analysis (PCA) and the -nearest neighbor ( -NN) algorithm. The novelty of this paper is to establish a systematic approach of load disaggregation through - trajectory-based load signature images by utilizing a multi-stage classification algorithm methodology. The contribution of this paper is in utilizing the “ -value,” the number of closest data points to the nearest neighbor, in the -NN algorithm to be effective in classification of electrical appliances. The results of the multi-stage classification algorithm implementation have been discussed and the idea on future work has also been proposed.

关键词: load disaggregation     voltage-current (V-I) trajectory     multi-stage classification algorithm     principal component analysis (PCA)     k-nearest neighbor (k-NN)    

Tailoring electrical conductivity of two dimensional nanomaterials using plasma for edge electronics:

Aswathy Vasudevan, Vasyl Shvalya, Aleksander Zidanšek, Uroš Cvelbar

《化学科学与工程前沿(英文)》 2019年 第13卷 第3期   页码 427-443 doi: 10.1007/s11705-019-1805-4

摘要: Since graphene has been discovered, two-dimensional nanomaterials have attracted attention due to their promising tunable electronic properties. The possibility of tailoring electrical conductivity at the atomic level allows creating new prospective 2D structures for energy harvesting and sensing-related applications. In this respect, one of the most successful way to manipulate the physical properties of the aforementioned materials is related to the surface modification techniques employing plasma. Moreover, plasma-gaseous chemical treatment can provide a controlled change in the bandgap, increase sensitivity and significantly improve the structural stability of material to the environment as well. This review deals with recent advances in the modification of 2D carbon nanostructures for novel ‘edge’ electronics using plasma technology and processes.

关键词: graphene     edge electronics     2D nanomaterials     plasma     electrical conductivity    

Fracture model for the prediction of the electrical percolation threshold in CNTs/Polymer composites

Yang SHEN, Pengfei HE, Xiaoying ZHUANG

《结构与土木工程前沿(英文)》 2018年 第12卷 第1期   页码 125-136 doi: 10.1007/s11709-017-0396-8

摘要: In this paper, we propose a 3D stochastic model to predict the percolation threshold and the effective electric conductivity of CNTs/Polymer composites. We consider the tunneling effect in our model so that the unrealistic interpenetration can be avoided in the identification of the conductive paths between the CNTs inside the polymer. The results are shown to be in good agreement with reported experimental data.

关键词: electrical percolation     CNTs/Polymer composites     fracture model     electric conductivity     tunnelling effects    

Study on electrical ignition and micro-explosion properties of HAN-based monopropellant droplet

Yonggang YU, Ming LI, Yanhuang ZHOU, Xin LU, Yuzhu PAN,

《能源前沿(英文)》 2010年 第4卷 第3期   页码 430-435 doi: 10.1007/s11708-010-0010-4

摘要: In order to study the electrical ignition characteristics of hydroxylammonium nitrate (HAN)-based liquid propellant, an experimental device for the electrical heating ignition of a liquid propellant droplet was designed. By using a high speed camera system, the ignition properties of the LP1846 single droplet were observed at different electrical heating speeds. The results show that when the LP1846 droplet is electrified, it mainly goes through an evaporization process, a periodic expansion and contraction process, a stronger thermal decomposition process, and an ignition and combustion process. The periodic expansion and contraction process accompanies the droplet micro-explosion phenomenon, and the micro-explosion mechanism is formed mainly due to the overheated water component in LP1846. When peak load voltage is from 80 to 140V/s, the ignition delay of the LP1846 droplet is linearly shortened from 0.82 to 0.62s, but the flame is lighter. Based on the above experiments, a simplified model of the electrical heating ignition of the LP1846 single droplet is established.

关键词: liquid propellant     electrical ignition     ignition delay time     transient measurement    

EEG controlled neuromuscular electrical stimulation of the upper limb for stroke patients

Hock Guan TAN, Cheng Yap SHEE, Keng He KONG, Cuntai GUAN, Wei Tech ANG

《机械工程前沿(英文)》 2011年 第6卷 第1期   页码 71-81 doi: 10.1007/s11465-011-0207-1

摘要:

This paper describes the Brain Computer Interface (BCI) system and the experiments to allow post-acute (<3 months) stroke patients to use electroencephalogram (EEG) to trigger neuromuscular electrical stimulation (NMES)-assisted extension of the wrist/fingers, which are essential pre-requisites for useful hand function. EEG was recorded while subjects performed motor imagery of their paretic limb, and then analyzed to determine the optimal frequency range within the -rhythm, with the greatest attenuation. Aided by visual feedback, subjects then trained to regulate their -rhythm EEG to operate the BCI to trigger NMES of the wrist/finger. 6 post-acute stroke patients successfully completed the training, with 4 able to learn to control and use the BCI to initiate NMES. This result is consistent with the reported BCI literacy rate of healthy subjects. Thereafter, without the loss of generality, the controller of the NMES is developed and is based on a model of the upper limb muscle (biceps/triceps) groups to determine the intensity of NMES required to flex or extend the forearm by a specific angle. The muscle model is based on a phenomenological approach, with parameters that are easily measured and conveniently implemented.

关键词: brain computer interface     neuromuscular electrical stimulation     stroke     musculoskeletal modeling    

Power sources and electrical recharging strategies for implantable medical devices

WEI Xiaojuan, LIU Jing

《能源前沿(英文)》 2008年 第2卷 第1期   页码 1-13 doi: 10.1007/s11708-008-0016-3

摘要: Implantable medical devices (IMDs) are critically requested for the survival of patients subject to certain serious diseases such as bradycardia, fibrillation, diabetes, and disability, etc. Appropriate working of an active implantable medical device (IMD) heavily relies on the continuous supply of electricity. In this sense, long-term powering and recharging of an IMD via a highly safe, efficient and convenient way is, therefore, extremely important in clinics. Several conventional batteries, such as lithium cell, nuclear cell and bio-fuel cell, etc., have been developed to power IMDs. Meanwhile, the recharge of IMD from outside of the human body is also under investigation. In this paper, some of the most typical IMD batteries are reviewed. Their advantages and disadvantages are compared. In addition, several emerging innovations to recharge or directly drive the implanted batteries, including electromagnetic energy transmission, piezoelectric power generation, thermoelectric devices, ultrasonic power motors, radio frequency recharging and optical recharging methods, etc., are also discussed. Some fundamental and practical issues thus involved are summarized, and future prospects in this area are made.

关键词: generation     bio-fuel     ultrasonic     piezoelectric     conventional    

Managing economic and social profit of cooperative models in three-echelon reverse supply chain for waste electrical

Jian Li, Zhen Wang, Bao Jiang

《环境科学与工程前沿(英文)》 2017年 第11卷 第5期 doi: 10.1007/s11783-017-0999-2

摘要: In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment (WEEE). The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In addition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain for WEEE.

关键词: Waste electrical and electronic equipment (WEEE)     Reverse supply chains     Recycle quantity     Social benefit     Cooperative models     Duopolistic retailers    

标题 作者 时间 类型 操作

机电装备的失效分析、安全评定和无损检测

钟群鹏,武淮生,张峥,田永江

期刊论文

Mechanical design and analysis of a novel variable stiffness actuator with symmetrical pivot adjustment

期刊论文

Recycling Materials from Waste Electrical and Electronic Equipment

Jinhui Li

期刊论文

EEG-controlled functional electrical stimulation rehabilitation for chronic stroke: system design and

期刊论文

CHARACTERISTICS OF HERBIVORY/WOUND-ELICITED ELECTRICAL SIGNAL TRANSDUCTION IN TOMATO

期刊论文

Engineering Fronts in fields of Energy and Electrical Science and Technologies in the report of

期刊论文

Combination of steam-enhanced extraction and electrical resistance heating for efficient remediation

期刊论文

A bionic approach for the mechanical and electrical decoupling of an MEMS capacitive sensor in ultralow

期刊论文

systematic approach in load disaggregation utilizing a multi-stage classification algorithm for consumer electrical

Chuan Choong YANG, Chit Siang SOH, Vooi Voon YAP

期刊论文

Tailoring electrical conductivity of two dimensional nanomaterials using plasma for edge electronics:

Aswathy Vasudevan, Vasyl Shvalya, Aleksander Zidanšek, Uroš Cvelbar

期刊论文

Fracture model for the prediction of the electrical percolation threshold in CNTs/Polymer composites

Yang SHEN, Pengfei HE, Xiaoying ZHUANG

期刊论文

Study on electrical ignition and micro-explosion properties of HAN-based monopropellant droplet

Yonggang YU, Ming LI, Yanhuang ZHOU, Xin LU, Yuzhu PAN,

期刊论文

EEG controlled neuromuscular electrical stimulation of the upper limb for stroke patients

Hock Guan TAN, Cheng Yap SHEE, Keng He KONG, Cuntai GUAN, Wei Tech ANG

期刊论文

Power sources and electrical recharging strategies for implantable medical devices

WEI Xiaojuan, LIU Jing

期刊论文

Managing economic and social profit of cooperative models in three-echelon reverse supply chain for waste electrical

Jian Li, Zhen Wang, Bao Jiang

期刊论文