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Experiment and surge analysis of centrifugal two-stage turbocharging system

HE Yituan, MA Chaochen

《机械工程前沿(英文)》 2008年 第3卷 第4期   页码 365-368 doi: 10.1007/s11465-008-0073-7

摘要: To study a centrifugal two-stage turbocharging system’s surge and influencing factors, a special test bench was set up and the system surge test was performed. The test results indicate that the measured parameters such as air mass flow and rotation speed of a high pressure (HP) stage compressor can be converted into corrected parameters under a standard condition according to the Mach number similarity criterion, because the air flow in a HP stage compressor has entered the Reynolds number () auto-modeling range. Accordingly, the reasons leading to a two-stage turbocharging system’s surge can be analyzed according to the corrected mass flow characteristic maps and actual operating conditions of HP and low pressure (LP) stage compressors.

关键词: auto-modeling     compressor     Reynolds number     characteristic     standard condition    

Research on the ecological compensation standard of the basin pollution control project based on evolutionary

Dongbin HU, Huiwu LIU, Xiaohong CHEN, Yang CHEN

《工程管理前沿(英文)》 2019年 第6卷 第4期   页码 575-583 doi: 10.1007/s42524-019-0044-1

摘要: Ecological compensation is a new resource and environment management model. As one of the main areas for implementing ecological compensation policies, basin ecological compensation has become an important measure for encouraging basin pollution control projects and improving the quality of regional economic development. By applying the basic game analysis of evolutionary game theory and building an evolutionary game model with a “reward–punishment” mechanism, this paper compares the interest-related decision-making behaviors of the upstream and downstream stakeholders of basin ecological compensation. By using data on the water quality of Xiangjiang River Basin, this paper calculates the rewards and penalties in different intervals by building a parametric regression mathematical model and employing the local linear regression method. Results show that a decline in water quality should be fined RMB 925500 yuan, an improvement in water quality should be awarded RMB 1227800 yuan, and a deteriorating water quality should be severely fined RMB 5087600 yuan.

关键词: evolutionary game     ecological compensation standard     Xiangjiang River Basin    

A review of condition-based maintenance: Its prognostic and operational aspects

Yanrong LI, Shizhe PENG, Yanting LI, Wei JIANG

《工程管理前沿(英文)》 2020年 第7卷 第3期   页码 323-334 doi: 10.1007/s42524-020-0121-5

摘要: Condition-based maintenance (CBM) detects early signs of failure and dictates when maintenance should be performed based on the actual condition of a system. In this paper, we first review some of the recent research on CBM under various physical structures and signal data. Then, we summarize several kinds of prognostic models that use monitoring information to estimate the reliability of complex systems or products. Monitoring information also facilitates operational decisions in production planning, spare parts management, reliability improvement, and prognostics and health management. Finally, we suggest some research opportunities for the reliability and operations management communities to fill the research gap between these two fields.

关键词: condition-based maintenance     prognostics     operational decision-making     reliability    

Trend prediction technology of condition maintenance for large water injection units

Xiaoli XU, Sanpeng DENG

《机械工程前沿(英文)》 2010年 第5卷 第2期   页码 171-175 doi: 10.1007/s11465-009-0091-0

摘要: Trend prediction technology is the key technology to achieve condition-based maintenance of mechanical equipment. Large-sized water injection units are key equipment in oilfields. The traditional preventive maintenance is not economical and cannot completely avoid vicious accidents. To ensure the normal operation of units and save maintenance costs, trend prediction technology is studied to achieve condition-based maintenance for water injection units. The main methods of the technology are given, the trend prediction method based on neural network is put forward, and the expert system based on the knowledge is developed. The industrial site verification shows that the proposed trend prediction technology can reflect the operating condition trend change of the water injection units and provide technical means to achieve condition-based predictive maintenance.

关键词: water injection units     condition-based maintenance     trend prediction    

Standard model of knowledge representation

Wensheng YIN

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 275-288 doi: 10.1007/s11465-016-0372-3

摘要:

Knowledge representation is the core of artificial intelligence research. Knowledge representation methods include predicate logic, semantic network, computer programming language, database, mathematical model, graphics language, natural language, etc. To establish the intrinsic link between various knowledge representation methods, a unified knowledge representation model is necessary. According to ontology, system theory, and control theory, a standard model of knowledge representation that reflects the change of the objective world is proposed. The model is composed of input, processing, and output. This knowledge representation method is not a contradiction to the traditional knowledge representation method. It can express knowledge in terms of multivariate and multidimensional. It can also express process knowledge, and at the same time, it has a strong ability to solve problems. In addition, the standard model of knowledge representation provides a way to solve problems of non-precision and inconsistent knowledge.

关键词: knowledge representation     standard model     ontology     system theory     control theory     multidimensional representation    

Overview of the quality standard research of traditional Chinese medicine

Huimin Gao, Zhimin Wang, Yujuan Li, Zhongzhi Qian

《医学前沿(英文)》 2011年 第5卷 第2期   页码 195-202 doi: 10.1007/s11684-011-0134-x

摘要: Traditional Chinese medicine (TCM) has been widely used for the prevention and treatment of various diseases for a long time in China. Due to its proven efficacy, wide applications, and low side effect, TCM has increasingly attracted worldwide attention. However, one of the biggest challenges facing the clinical practice of TCM is the uncontrollable quality. In this review, the progress of the development and the current status of quality standard as well as new quality control techniques introduced in (2010 edition), such as liquid chromatography hyphenated mass spectrometry (LC-MS), fingerprint, quantitative analysis of multi-components by single-marker (QAMS), thin layer chromatography bio-autographic assay (TLC-BAA), and DNA molecular marker technique, are briefly overviewed.

关键词: traditional Chinese medicine     quality standard     quality control     quantitative analysis of multi-components by single-marker    

A Standard for the Commissioning Process

William L. Gillis,Elizabeth A. Cudney

《工程管理前沿(英文)》 2015年 第2卷 第1期   页码 39-51 doi: 10.15302/J-FEM-2015006

摘要: The demand for commissioning services for new-building construction projects is experiencing rapid growth. Commissioning (Cx) is touted as being a quality-focused process for ensuring the owner’s project requirements (OPR) are met by design, final construction, and the operations of a building. To an owner this is just what is needed to receive a perfect building at occupancy. However, as many owners have realized, the Cx process does not guarantee the completed building will be what was expected. It should be pointed out that this is typically not caused by the Cx process, but the Cx process should or could have identified, in the early phases of the project, many of the issues that made it through to the completed building. There are a number of reasons why the Cx services received may not be optimal. Often it is poor communication and the transfer of knowledge between project teams. Cx should and can facilitate both communication and the transfer of knowledge from phase to phase. An adaptation of the quality function deployment (QFD) four-phase model can accomplish this by filling the gaps among the major Cx activities and provide a standard approach to the process. The four-phase model effectively links each of the Cx activities to each other and back to the OPR, providing a method for improved communication and knowledge transfer. This paper investigates some potential reasons for inconsistent Cx services, presents an argument for the need of a Cx standard, and proposes a potential standard.

关键词: construction     engineering management     quality     commissioning    

Real-time tool condition monitoring method based on temperature measurement and artificial neural network

《机械工程前沿(英文)》 doi: 10.1007/s11465-021-0661-3

摘要: Tool failures in machining processes often cause severe damages of workpieces and lead to large quantities of loss, making tool condition monitoring an important, urgent issue. However, problems such as practicability still remain in actual machining. Here, a real-time tool condition monitoring method integrated in an in situ fiber optic temperature measuring apparatus is proposed. A thermal simulation is conducted to investigate how the fluctuating cutting heats affect the measuring temperatures, and an intermittent cutting experiment is carried out, verifying that the apparatus can capture the rapid but slight temperature undulations. Fourier transform is carried out. The spectrum features are then selected and input into the artificial neural network for classification, and a caution is given if the tool is worn. A learning rate adaption algorithm is introduced, greatly reducing the dependence on initial parameters, making training convenient and flexible. The accuracy stays 90% and higher in variable argument processes. Furthermore, an application program with a graphical user interface is constructed to present real-time results, confirming the practicality.

关键词: tool condition monitoring     cutting temperature     neural network     learning rate adaption    

Benzene removal by nano magnetic particles under continuous condition from aqueous solutions

Amin Mohammad Mehdi,Bina Bijan,Majd Amir Masoud Samani,Pourzamani Hamidreza

《环境科学与工程前沿(英文)》 2014年 第8卷 第3期   页码 345-356 doi: 10.1007/s11783-013-0574-4

摘要: Benzene removal from aqueous solutions was evaluated using Fe O nano magnetic particles (NM) in continuous condition. A 4 factorial design including initial benzene concentration, NM dose, contact time and pH was investigated in 16 experiments (Taguchi OA design). The results indicated that all factors were significant and the optimum condition was: pH 8, NM dose of 2000 mg·L , benzene concentrations of 100 mg·L and contact time of 14 min. The maximum benzene uptake and distribution ratio in the optimum situation were 49.4 mg·g and 38.4 L·g , respectively. The nano particles were shown to capture 98.7% of the benzene in optimum batch condition and 94.5% in continuous condition. The isotherm data proved that the Brunauer-Emmett-Teller model fit more closely and produced an isotherm constant (b) less than one, indicating favorable adsorption. Regeneration studies verified that the benzene adsorbed by the NM could be easily desorbed by temperature, and thereby, NM can be employed repeatedly in water and wastewater management.

关键词: benzene     experimental design     Fe3O4     continues condition     thermal recycling    

Quantitative standard of eco-compensation for the water source area in the middle route of the South-to-North

Zhanfeng DONG, Jinnan WANG

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 459-473 doi: 10.1007/s11783-010-0288-9

摘要: The Middle Route Project(MRP) of the South-to-North Water Transfer Scheme (SNWT) in China will require a very large financial expenditure to ensure the water supply and the associated water quality to northern China. An eco-compensation mechanism between the water service source areas and its beneficiaries is essential. This paper establishes an analytic framework of eco-compensation standard for the protection of the water source area, including both the calculation of eco-compensation based on opportunity cost method (OCM) and calculation of the burden sharing of eco-compensation between the water source area and the external water reception area based on the deviation square method (DSM). Taking Shiyan City, Hubei Province in China as a case study, our results show that the eco-compensation in the first-phase of MRP for the water source area in Shiyan, Hubei Province should be 1.63×10 CNY, about four times of planned eco-construction investment budget(4.33×10 CNY). In addition, the burden sharing of eco-compensation varied greatly in terms of different methods. It would be better to integrate the results of different single-factor burden sharing methods by determining the corresponding weighting coefficient with DSM and form one unanimous consent result by the interested parties.

关键词: the South-to-North Water Transfer Scheme     eco-compensation standard     opportunity costs     deviation square method    

In-situ condition monitoring of reinforced concrete structures

Sanjeev Kumar VERMA,Sudhir Singh BHADAURIA,Saleem AKHTAR

《结构与土木工程前沿(英文)》 2016年 第10卷 第4期   页码 420-437 doi: 10.1007/s11709-016-0336-z

摘要: Performance of concrete structures is significantly influenced and governed by its durability and resistance to environmental or exposure conditions, apart from its physical strength. It can be monitored, evaluated and predicted through modeling of physical deterioration mechanisms, performance characteristics and parameters and condition monitoring of in situ concrete structures. One such study has been conducted using Non-destructive testing equipment in the city of Bhopal and around located in India. Some selected parameters influencing durability of reinforced concrete (RC) structures such as concrete cover, carbonation depth, chloride concentration, half cell potential and compressive strength have been measured, for establishing correlation among various parameters and age of structures. Effects of concrete cover and compressive strength over the variation of chloride content with time are also investigated.

关键词: concrete     carbonation     chloride     corrosion     monitoring     models    

Optimization of the power, efficiency and ecological function for an air-standard irreversible Dual-Miller

Zhixiang WU, Lingen CHEN, Yanlin GE, Fengrui SUN

《能源前沿(英文)》 2019年 第13卷 第3期   页码 579-589 doi: 10.1007/s11708-018-0557-z

摘要: This paper establishes an irreversible Dual-Miller cycle (DMC) model with the heat transfer (HT) loss, friction loss (FL) and other internal irreversible losses. To analyze the effects of the cut-off ratio ( ) and Miller cycle ratio ( ) on the power output ( ), thermal efficiency ( ) and ecological function ( ), obtain the optimal and optimal , and compare the performance characteristics of DMC with its simplified cycles and with different optimization objective functions, the , and of irreversible DMC are analyzed and optimized by applying the finite time thermodynamic (FTT) theory. Expressions of , and are derived. The relationships among , , and compression ratio ( ) are obtained by numerical examples. The effects of and on , , , maximum power output ( ), maximum efficiency ( ) and maximum ecological function ( ) are analyzed. Performance differences among the DMC, the Otto cycle (OC), the Dual cycle (DDC), and the Otto-Miller cycle (OMC) are compared for fixed design parameters. Performance characteristics of irreversible DMC with the choice of , and as optimization objective functions are analyzed and compared. The results show that the irreversible DMC engine can reach a twice-maximum power, a twice-maximum efficiency, and a twice-maximum ecological function, respectively. Moreover, when choosing as the optimization objective, there is a 5.2% of improvement in while there is a drop of only 2.7% in compared to choosing as the optimization objective. However, there is a 5.6% of improvement in while there is a drop of only 1.3% in compared to choosing as the optimization objective.

关键词: finite-time thermodynamics     Dual-Miller cycle     power output     thermal efficiency     ecological function    

Distributed flexible reconfigurable condition monitoring and diagnosis technology

HU You-min, YANG Shu-zi, DU Run-sheng

《机械工程前沿(英文)》 2006年 第1卷 第3期   页码 276-281 doi: 10.1007/s11465-006-0025-z

摘要: As manufacturing becomes increasingly decentralized, flexible and reconfigurable, more research needs to be done on monitoring and diagnosis technology that accommodate these new trends. The distributed condition monitoring and diagnosis technology based on the flexible and reconfigurable concept is studied here. A condition monitoring diagnosis model based on the distributed flexible and reconfigurable idea is proposed in this paper. The component makeup and functions of this model are discussed in detail. The model can fulfill in most instances the manufacturing system requirements for changing the configuration of the monitoring diagnosis system according to different manufacturing system configurations. This model also realizes the flexibility and reconfigurability of the monitoring diagnosis system in some degree. The model has already spawned a successful prototype for monitoring a chemical plant in accomplishing monitoring and control of the production process and equipment. Finally, some future research work is pointed out.

关键词: chemical     diagnosis system     configuration     monitoring     equipment    

Comprehensive health condition assessment on partial sewers in a southern Chinese city based on fuzzy

Lili GAN, Jiane ZUO, Yajiao WANG, Thong Soon LOW, Kaijun WANG

《环境科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 144-150 doi: 10.1007/s11783-013-0554-8

摘要: A self-developed sewer health assessment system using the fuzzy comprehensive evaluation and analytical hierarchy process was applied to give a comprehensive health condition evaluation on part of the local sewers in a southern Chinese city based on the sewer video data collected by a sewer inspection closed circuit television (CCTV) robot. Aside from the overall condition evaluation, the structure, function, and stability status of the sewer were also analyzed using the method. A comprehensive index was proposed to give the overall health condition of pipes with different defects, and , , and were used to quantify the defects affecting the tightness, stability, and function of the pipe, respectively. Results show that 48% of the inspected pipes were in good condition (0< <0.25), and about 33% of the sewer pipes analyzed were categorized to be at severe or urgent condition levels ( >0.5), although most of the pipes were installed only within five years. Frequent sedimentation affects the function of the sewer, and deformation and joint damage affect the structure of the sewer.

关键词: sewer     health condition assessment     analytical hierarchy process     fuzzy comprehensive evaluation     fuzzy mathematic method    

Effects of Boundary Condition and Helix Angle on Meshing Performance of TI Worm Gearing

SUN Yue-hai, DUAN Lu-qian, WANG Shu-ren, ZHANG Ce

《机械工程前沿(英文)》 2006年 第1卷 第1期   页码 90-95 doi: 10.1007/s11465-005-0006-7

摘要:

To exactly describe the contact state and contact area of tooth surface of toroidal involute (TI) worm gearing, the authors introduced boundary condition into contact line analysis.With helix angle chosen as parameter, the criterion for the existence of meshing boundary line on the surface of TI worm gearing is derived. Results show that there can be four situations for meshing boundary line on the tooth surface of gear, namely, inexistence of meshing boundary line, a unique line, two lines, and two coincident lines. If the helix angle is equal to or slightly smaller than the bigger angle, which makes two meshing boundary lines superpose, a preferable meshing performance is obtained. Computer simulation proves the validity of the above conclusion.

关键词: preferable     inexistence     Results     validity     boundary condition    

标题 作者 时间 类型 操作

Experiment and surge analysis of centrifugal two-stage turbocharging system

HE Yituan, MA Chaochen

期刊论文

Research on the ecological compensation standard of the basin pollution control project based on evolutionary

Dongbin HU, Huiwu LIU, Xiaohong CHEN, Yang CHEN

期刊论文

A review of condition-based maintenance: Its prognostic and operational aspects

Yanrong LI, Shizhe PENG, Yanting LI, Wei JIANG

期刊论文

Trend prediction technology of condition maintenance for large water injection units

Xiaoli XU, Sanpeng DENG

期刊论文

Standard model of knowledge representation

Wensheng YIN

期刊论文

Overview of the quality standard research of traditional Chinese medicine

Huimin Gao, Zhimin Wang, Yujuan Li, Zhongzhi Qian

期刊论文

A Standard for the Commissioning Process

William L. Gillis,Elizabeth A. Cudney

期刊论文

Real-time tool condition monitoring method based on temperature measurement and artificial neural network

期刊论文

Benzene removal by nano magnetic particles under continuous condition from aqueous solutions

Amin Mohammad Mehdi,Bina Bijan,Majd Amir Masoud Samani,Pourzamani Hamidreza

期刊论文

Quantitative standard of eco-compensation for the water source area in the middle route of the South-to-North

Zhanfeng DONG, Jinnan WANG

期刊论文

In-situ condition monitoring of reinforced concrete structures

Sanjeev Kumar VERMA,Sudhir Singh BHADAURIA,Saleem AKHTAR

期刊论文

Optimization of the power, efficiency and ecological function for an air-standard irreversible Dual-Miller

Zhixiang WU, Lingen CHEN, Yanlin GE, Fengrui SUN

期刊论文

Distributed flexible reconfigurable condition monitoring and diagnosis technology

HU You-min, YANG Shu-zi, DU Run-sheng

期刊论文

Comprehensive health condition assessment on partial sewers in a southern Chinese city based on fuzzy

Lili GAN, Jiane ZUO, Yajiao WANG, Thong Soon LOW, Kaijun WANG

期刊论文

Effects of Boundary Condition and Helix Angle on Meshing Performance of TI Worm Gearing

SUN Yue-hai, DUAN Lu-qian, WANG Shu-ren, ZHANG Ce

期刊论文