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Role of stair-climbing test in predicting postoperative cardiopulmonary complications in elderly patients

Pei-Tu REN BM, Bao-Chun LU MM, Zhi-Liang CHEN MM, Hong FU MM,

《医学前沿(英文)》 2010年 第4卷 第1期   页码 77-81 doi: 10.1007/s11684-010-0005-x

摘要: One hundred and twenty-six patients above 80 years old with biliary diseases undergoing operations in Shaoxing People’s Hospital from Jan. 2002 to Jan. 2007 were analyzed retrospectively. All patients performed a preoperative stair-climbing test, and the risks for cardiopulmonary €complications were evaluated with pair-matching and linear correlations analysis between stair-climbing height (h) and left ventricular ejective factor (EF), forced vital capacity (FVC) and forced expiratory volume in one second (FEV). There was a significant difference in the incidence of cardiopulmonary complications among different stair-climbing heights. Stair-climbing heights were positively related with EF, FVC and FEV. This suggests that the stair-climbing test is an effective and simple method for predicting cardiopulmonary complications in elderly patients with biliary diseases.

关键词: biliary disease     cardiopulmonary complication     stair-climbing test    

Innovative stair climber using associated wheels

Girish Sudhir MODAK,Manmohan Manikrao BHOOMKAR

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 299-310 doi: 10.1007/s11465-016-0374-1

摘要:

The study proposes an innovative and completely new but low-cost configuration of a platform that can easily climb stairs. This platform serves the purpose of a chassis. Different versions, such as staircase-climbing wheelchair or staircase-climbing trolley for material transferring, can be derived depending on the structure built on the platform. The driving wheels have a shape that completely matches with the profile of the steps. Complex components are eliminated. Thus, this platform is conveniently applicable in the configurations useful for climbing staircases.

关键词: stair-climbing platform     matching wheels     impaired mobility     affordable configuration    

Review of key technologies of climbing robots

《机械工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11465-023-0764-0

摘要: In recent years, the robot industry has developed rapidly, and researchers and enterprises have begun to pay more attention to this industry. People are barely familiar with climbing robots, a kind of special robot. However, from their practical value and scientific research value, climbing robots should studied further. This paper analyzes and summarizes the key technologies of climbing robots, introduces various kinds of climbing robots, and examines their advantages and disadvantages to provide a reference for future researchers. Many countries have studied climbing robots and made some achievements. However, due to the complexity of climbing robots, their climbing efficiency and accuracy need to be further improved. The new structure can improve the climbing efficiency. This paper analyzes climbing robots such as mechanical arms, magnetic attraction, and claws. Optimization methods and path planning can improve the accuracy of work. This paper involves some control methods, including complex intelligent control methods such as behavior-based robot control. This paper also investigates various kinematic planning methods and expounds and summarizes various path planning algorithms, including machine learning and reinforcement learning of artificial intelligence, ant colony algorithm, and other algorithms. Therefore, by analyzing the research status of climbing robots at home and abroad, this paper summarizes three important aspects of climbing robots, namely, structural design, control methods, and climbing strategies, elaborates on the achievements and existing problems of these key technologies, and looks forward to the future development trend and research direction of climbing robots.

关键词: climbing robot     mechanical structure design     control system     kinematics planning     path planning    

三峡工程齿轮齿条爬升式升船机设计

钮新强,覃利明,于庆奎

《中国工程科学》 2011年 第13卷 第7期   页码 96-103

摘要:

三峡升船机具有提升重量大、升程高、上下游通航水位变幅大、水位变率快等特点,是目前世界上规模和技术难度最大的升船机。经过方案比选,三峡升船机最终确定采用齿轮齿条爬升式,其设备构造复杂,制造、安装及土建结构施工精度要求很高,并首次采用中德联合设计方式。概要介绍了三峡工程齿轮齿条爬升式升船机的总体布置、以及塔柱结构、重要设备的设计方案与关键技术。

关键词: 升船机     爬升式     安全机构     行程同步    

三峡升船机液压自升式模板施工技术

戴志清

《中国工程科学》 2013年 第15卷 第9期   页码 22-26

摘要:

三峡升船机塔柱混凝土施工工期紧,精度要求高,为保证施工进度和质量,采用了液压自升式模板。本文重点介绍了三峡升船机塔柱混凝土液压自升式模板施工技术、自升式模板改进措施以及为满足自升式模板上升而在塔柱板梁、牛腿处进行的结构处理措施。实践证明,液压自升式模板施工技术的应用与改进满足了三峡升船机塔柱筒体混凝土的设计要求,有效地提高施工效率、节约了成本,保证了工程质量并提高施工的安全性,可为其他水电工程施工提供借鉴。

关键词: 塔柱混凝土     液压自升式模板     混凝土浇筑     三峡升船机    

Evacuation strategies for vertical ship lift during initial fire: Integrated application of stairs and elevators

Shu CHEN, Menghan SHANG, Jianping WANG

《工程管理前沿(英文)》 2021年 第8卷 第1期   页码 135-147 doi: 10.1007/s42524-020-0125-1

摘要: Vertical ship lifts (VSLs) are widely used in navigation facilities worldwide because of their efficiency and low cost. Although several researchers have investigated fire evacuation strategies for reducing potential safety hazards in VSLs, an effective and integrated application of stairs and elevators when a fire occurs in a VSL is necessary. Several evacuation routes were analyzed according to VSL structure and evacuation times in this study. Objective function corresponding to the minimum vertical evacuation time and related simulation model was subsequently developed to obtain a cooperative evacuation plan considering different numbers of evacuees. The Three Gorges ship lift was used as an example, and simulation results indicate that number of evacuees and exit selection are the main influencing factors of the total evacuation time in the stair- and elevator-coordinated evacuation mode. Furthermore, the distance between people trapped in ship reception chamber and evacuation exits affects evacuees’ choice of exits. The proposed model can provide a theoretical reference for evacuation research during initial fire events in VSLs.

关键词: vertical ship lift     initial fire     fire evacuation     numerical simulation     stair     elevator    

Learning from biological attachment devices: applications of bioinspired reversible adhesive methods in robotics

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0699-x

摘要: Many organisms have attachment organs with excellent functions, such as adhesion, clinging, and grasping, as a result of biological evolution to adapt to complex living environments. From nanoscale to macroscale, each type of adhesive organ has its own underlying mechanisms. Many biological adhesive mechanisms have been studied and can be incorporated into robot designs. This paper presents a systematic review of reversible biological adhesive methods and the bioinspired attachment devices that can be used in robotics. The study discussed how biological adhesive methods, such as dry adhesion, wet adhesion, mechanical adhesion, and sub-ambient pressure adhesion, progress in research. The morphology of typical adhesive organs, as well as the corresponding attachment models, is highlighted. The current state of bioinspired attachment device design and fabrication is discussed. Then, the design principles of attachment devices are summarized in this article. The following section provides a systematic overview of climbing robots with bioinspired attachment devices. Finally, the current challenges and opportunities in bioinspired attachment research in robotics are discussed.

关键词: adhesion     bioinspired attachment     biomimetic gripper     climbing robot    

一种用于寻找无人船回收海床基数据最佳通信点的梯度上升控制法 Research Papers

Jiu-cai JIN, Jie ZHANG, Zhi-chao LV

《信息与电子工程前沿(英文)》 2019年 第20卷 第6期   页码 751-759 doi: 10.1631/FITEE.1700732

摘要: 给出了一种在无人船声学回收海床基数据时寻找最佳通信点的控制方法。众所周知,梯度上升极值寻找法常应用于多平台或多智能体,这是因为多平台能大范围测量且易于梯度估计。单一平台测量范围有限,不能快速估计测量场,难以迅速获得测量场极值。本文提出一种无人船振荡运动形式,以获取海床基与无人船间水声通信链路强度数据。基于多元加权线性递归法,利用无人船振荡运动获取的新数据,不断更新水声通信链路强度场。基于梯度上升和人工势场方法,考虑未知场的递归估计,设计无人船最佳通信点控制器,并证明其稳定性。仿真结果表明该算法可靠、高效。

关键词: 无人船;数据回收;水声通信;梯度上升;极值寻找    

Mechanical performance analysis and stiffness test of a new type of suspension bridge

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1160-1180 doi: 10.1007/s11709-021-0760-6

摘要: A new type of suspension bridge is proposed based on the gravity stiffness principle. Compared with a conventional suspension bridge, the proposed bridge adds rigid webs and cross braces. The rigid webs connect the main cable and main girder to form a truss that can improve the bending stiffness of the bridge. The cross braces connect the main cables to form a closed space truss structure that can improve the torsional stiffness of the bridge. The rigid webs and cross braces are installed after the construction of a conventional suspension bridge is completed to resist different loads with different structural forms. A new type of railway suspension bridge with a span of 340 m and a highway suspension bridge with a span of 1020 m were designed and analysed using the finite element method. The stress, deflection of the girders, unbalanced forces of the main towers, and natural frequencies were compared with those of conventional suspension bridges. A stiffness test was carried out on the new type of suspension bridge with a small span, and the results were compared with those for a conventional bridge. The results showed that the new suspension bridge had a better performance than the conventional suspension bridge.

关键词: new type of suspension bridge     stiffness test     mechanical performance     railway bridge     space truss    

Accelerated life-time test of MEA durability under vehicle operating conditions in PEM fuel cell

Tian TIAN, Jianjun TANG, Wei GUO, Mu PAN

《能源前沿(英文)》 2017年 第11卷 第3期   页码 326-333 doi: 10.1007/s11708-017-0489-z

摘要: In this paper, a novel accelerated test method was proposed to analyze the durability of MEA, considering the actual operation of the fuel cell vehicle. The proposed method includes 7 working conditions: open circuit voltage (OCV), idling, rated output, overload, idling-rated cycle, idling-overload cycle, and OCV-idling cycle. The experimental results indicate that the proposed method can effectively destroy the MEA in a short time (165 h). Moreover, the degradation mechanism of MEA was analyzed by measuring the polarization curve, CV, SEM and TEM. This paper may provide a new research direction for improving the durability of fuel cell.

关键词: polymer electrolyte membrane fuel cell     accelerated life-time test     load cycling test     durability    

Mixed mode properties of CNT reinforced composites using Arcan test rig

Jacob MUTHU

《结构与土木工程前沿(英文)》 2015年 第9卷 第4期   页码 397-404 doi: 10.1007/s11709-015-0321-y

摘要: Composite materials reinforced with carbon nanotubes were mechanical tested using Arcan test rig under Mode-I, Mode-II and mixed mode loading conditions to obtain their fracture properties. The butterfly composite specimens were fabricated with 0.02, 0.05 and 0.1 wt % CNTs. The polyester/CNT composite was fabricated using VRTM (Vacuum Resin Transfer Molding) where the CNTs were first functionalised to reach an optimum properties. Arcan test rig was designed and fabricated to work with the Shimadzu testing machine. The results show that the functionalised CNTs have improved the fracture behavior by acting as bridge between the cracked face. In addition, the fracture properties were not improved for the higher weight fraction of 0.1 wt% CNTs.

关键词: CNT     composites     Arcan test rig     stress intensity factor    

XB高精度火箭橇试验滑轨

杨兴邦

《中国工程科学》 2000年 第2卷 第10期   页码 98-104

摘要:

火箭橇试验滑轨是一种大型地面动态模拟试验设备,用于研究试验件在空中高速度、高加速度运行时所遇到的诸多技术问题,其技术核心是一百万分之一的轨道直线性相对精度。它要求具有稳定的滑轨基础、高直线度准直基准线和光滑平顺的钢轨作为基本条件,需要采用钢轨精密机械加工、钢轨焊接、焊缝超声波探伤、轨道张拉锚固锁定、轨道直线度调整等新工艺技术。我国已成功地建成世界上唯一的、钢轨经精密机械加工后再全程焊接的XB高精度火箭橇试验滑轨。文章论述了它的诞生背景、设计思路、技术方案、技术与建造特点以及应用展望,该滑轨直线度达到世界先进水平。

关键词: 火箭滑橇     试验滑轨     地面动态模拟试验    

Application of metal magnetic memory test in failure analysis and safety evaluation of vessels

Yiliang ZHANG, Song YANG, Xuedong XU

《机械工程前沿(英文)》 2009年 第4卷 第1期   页码 40-48 doi: 10.1007/s11465-009-0003-3

摘要: Metal magnetic memory test (MMMT), which is a new subject in the field of nondestructive examination, can determine regions of stress concentration by testing the distribution of the magnetic field of metal structures so as to effectively diagnose premature defects. MMMT and other test methods are applied in the study to put a propylene purifier of a temperature-jump accident and a leaked ammonia vessel through safety evaluation. Results are as follows: The margin of safety declines after the purifier is overburnt; several stress concentrations are observed within the overburnt area and the level of stress concentration rises after one-month operation; and overpressure operation of the purifier must be strictly avoided and carefully monitored during later operation. Cracks are observed on the ammonia vessel after one year’s service. Extremely high residual stress is the primary cause of cracks. After four years in service, the residual stresses existing in the area of the base metal and weld zone are still greater than 0.5 , which results in numerous cracks due to stress corrosion. From the MMMT result of the ammonia vessel’s defects, it can be seen that the derivative of magnetic density (d p/d ) is an important reference variable. Within the 31 leakage points, 67.7% of them whose dHp/dx values are more than 10, and 96.8% of them whose dHp/dx values are more than 8.

关键词: Metal magnetic memory test (MMMT)     nondestructive testing (NDT)     residual stress     propylene purifier     ammonia vessel    

Investigating the raveling test for full-depth reclamation

Robert HILL, Andrew BRAHAM

《结构与土木工程前沿(英文)》 2018年 第12卷 第2期   页码 222-226 doi: 10.1007/s11709-017-0423-9

摘要: Full-Depth Reclamation (FDR) is a sustainable method of building pavement structure compared to more traditional rehabilitation methods. Traffic is generally returned to an FDR project before a surface course is applied, as water in the FDR needs time to evaporate from the structure. This should not be done too quickly or raveling occurs. Currently, there is no test to quantify the timing of return to traffic. In this study, the “Raveling test of cold mixed bituminous emulsion samples” (ASTM D7196) was used to compare asphalt emulsion and asphalt foam FDR. Asphalt emulsion samples were cured at ambient and 40 °C temperatures, while asphalt foam samples were cured at ambient temperatures. Raveling test data was collected from 0 to 48 hours of curing, however, samples were often not able to withstand fifteen minutes of testing. Therefore, the “time lasted” (the time the raveling head loses contact with the surface of the sample) was recorded. In general, the asphalt emulsion samples that were cured in the oven at 40 °C had a longer time lasted and showed higher potential for determination of return to traffic. In addition, the asphalt emulsion samples had a longer time lasted than the asphalt foam samples at ambient temperatures.

关键词: raveling     full depth reclamation    

Fault evolution-test dependency modeling for mechanical systems

Xiao-dong TAN,Jian-lu LUO,Qing LI,Bing LU,Jing QIU

《信息与电子工程前沿(英文)》 2015年 第16卷 第10期   页码 848-857 doi: 10.1631/FITEE.1500011

摘要: Tracking the process of fault growth in mechanical systems using a range of tests is important to avoid catastrophic failures. So, it is necessary to study the design for testability (DFT). In this paper, to improve the testability performance of mechanical systems for tracking fault growth, a fault evolution-test dependency model (FETDM) is proposed to implement DFT. A testability analysis method that considers fault trackability and predictability is developed to quantify the testability performance of mechanical systems. Results from experiments on a centrifugal pump show that the proposed FETDM and testability analysis method can provide guidance to engineers to improve the testability level of mechanical systems.

关键词: Mechanical systems     Design for testability (DFT)     Fault evolution-test dependency model (FETDM)    

标题 作者 时间 类型 操作

Role of stair-climbing test in predicting postoperative cardiopulmonary complications in elderly patients

Pei-Tu REN BM, Bao-Chun LU MM, Zhi-Liang CHEN MM, Hong FU MM,

期刊论文

Innovative stair climber using associated wheels

Girish Sudhir MODAK,Manmohan Manikrao BHOOMKAR

期刊论文

Review of key technologies of climbing robots

期刊论文

三峡工程齿轮齿条爬升式升船机设计

钮新强,覃利明,于庆奎

期刊论文

三峡升船机液压自升式模板施工技术

戴志清

期刊论文

Evacuation strategies for vertical ship lift during initial fire: Integrated application of stairs and elevators

Shu CHEN, Menghan SHANG, Jianping WANG

期刊论文

Learning from biological attachment devices: applications of bioinspired reversible adhesive methods in robotics

期刊论文

一种用于寻找无人船回收海床基数据最佳通信点的梯度上升控制法

Jiu-cai JIN, Jie ZHANG, Zhi-chao LV

期刊论文

Mechanical performance analysis and stiffness test of a new type of suspension bridge

期刊论文

Accelerated life-time test of MEA durability under vehicle operating conditions in PEM fuel cell

Tian TIAN, Jianjun TANG, Wei GUO, Mu PAN

期刊论文

Mixed mode properties of CNT reinforced composites using Arcan test rig

Jacob MUTHU

期刊论文

XB高精度火箭橇试验滑轨

杨兴邦

期刊论文

Application of metal magnetic memory test in failure analysis and safety evaluation of vessels

Yiliang ZHANG, Song YANG, Xuedong XU

期刊论文

Investigating the raveling test for full-depth reclamation

Robert HILL, Andrew BRAHAM

期刊论文

Fault evolution-test dependency modeling for mechanical systems

Xiao-dong TAN,Jian-lu LUO,Qing LI,Bing LU,Jing QIU

期刊论文