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High-precision standard enthalpy of formation for polycyclic aromatic hydrocarbons predicting from general

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1743-1750 doi: 10.1007/s11705-022-2184-9

摘要： The standard enthalpy of formation is an important predictor of the reaction heat of a chemical reaction. In this work, a high-precision method was developed to calculate accurate standard enthalpies of formation for polycyclic aromatic hydrocarbons based on the general connectivity based hierarchy (CBH) with the discrete correction of atomization energy. Through a comparison with available experimental findings and other high-precision computational results, it was found that the present method can give a good description of enthalpy of formation for polycyclic aromatic hydrocarbons. Since CBH schemes can broaden the scope of application, this method can be used to investigate the energetic properties of larger polycyclic aromatic hydrocarbons to achieve a high-precision calculation at the CCSD(T)/CBS level. In addition, the energetic properties of CBH fragments can be accurately calculated and integrated into a database for future use, which will increase computational efficiency. We hope this work can give new insights into the energetic properties of larger systems.

关键词： standard enthalpy of formation     polycyclic aromatic hydrocarbons     connectivity based hierarchy     high-precision calculation    

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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    

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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    

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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    

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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    

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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    

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Time-varying formation tracking for uncertain second-order nonlinearmulti-agent systems

Mao-peng RAN, Li-hua XIE, Jun-cheng LI

《信息与电子工程前沿（英文）》 2019年 第20卷 第1期   页码 76-87 doi: 10.1631/FITEE.1800557

摘要：

Our study is concerned with the time-varying formation tracking problem for second-order multi-agent systems that are subject to unknown nonlinear dynamics and external disturbance, and the states of the followers form a predefined time-varying formation while tracking the state of the leader. The total uncertainty lumps the unknown nonlinear dynamics and the external disturbance, and is regarded as an extended state of the agent. To estimate the total uncertainty, we design an extended state observer (ESO). Then we propose a novel ESO based time-varying formation tracking protocol. It is proved that, under the proposed protocol, the ESO estimation error and the time-varying formation tracking error can be made arbitrarily small. An application to the target enclosing problem for multiple unmanned aerial vehicles (UAVs) verifies the effectiveness and superiority of the proposed approach.

关键词： Multi-agent system     Time-varying formation     Formation tracking     Nonlinear dynamics     Extended state observer (ESO)    

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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    

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3D finite element prediction of chip flow, burr formation, and cutting forces in micro end-milling of

A. DAVOUDINEJAD, P. PARENTI, M. ANNONI

《机械工程前沿（英文）》 2017年 第12卷 第2期   页码 203-214 doi: 10.1007/s11465-017-0421-6

摘要：

Predictive models for machining operations have been significantly improved through numerous methods in recent decades. This study proposed a 3D finite element modeling (3D FEM) approach for the micro end-milling of Al6061-T6. Finite element (FE) simulations were performed under different cutting conditions to obtain realistic numerical predictions of chip flow, burr formation, and cutting forces. FE modeling displayed notable advantages, such as capability to easily handle any type of tool geometry and any side effect on chip formation, including thermal aspect and material property changes. The proposed 3D FE model considers the effects of mill helix angle and cutting edge radius on the chip. The prediction capability of the FE model was validated by comparing numerical model and experimental test results. Burr dimension trends were correlated with force profile shapes. However, the FE predictions overestimated the real force magnitude. This overestimation indicates that the model requires further development.

关键词： 3D finite element modeling     micro end-milling     cutting force     chip formation     burr formation    

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Mechanistic insight into the biofilm formation and process performance of a passive aeration ditch (PAD

《环境科学与工程前沿（英文）》 2022年 第16卷 第7期 doi: 10.1007/s11783-021-1494-3

摘要：

• A Passive Aeration Ditch was developed to treat decentralized wastewater.

关键词： Decentralized wastewater     Passive aeration ditch     Biofilm formation     C/N ratio     Salinity     Model simulation    

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Is atmospheric oxidation capacity better in indicating tropospheric O formation?

《环境科学与工程前沿（英文）》 2022年 第16卷 第5期 doi: 10.1007/s11783-022-1544-5

摘要：

● This study summarizes and evaluates different approaches that indicate O3 formation.

关键词： O3     AOC     O3 formation regime    

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Formation mechanism and modeling of surface waviness in incremental sheet forming

《机械工程前沿（英文）》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0679-1

摘要： Improving and controlling surface quality has always been a challenge for incremental sheet forming (ISF), whereas the generation mechanism of waviness surface is still unknown, which impedes the widely application of ISF in the industrial field. In this paper, the formation mechanism and the prediction of waviness are both investigated through experiments, numerical simulation, and theoretical analysis. Based on a verified finite element model, the waviness topography is predicted numerically for the first time, and its generation is attributed to the residual bending deformation through deformation history analysis. For more efficient engineering application, a theoretical model for waviness height is proposed based on the generation mechanism, using a modified strain function considering deformation modes. This work is favorable for the perfection of formation mechanism and control of surface quality in ISF.

关键词： surface waviness     incremental sheet forming     numerical simulation     formation mechanism     deformation history    

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New insights into the formation of ammonium nitrate from a physical and chemical level perspective

《环境科学与工程前沿（英文）》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1737-6

摘要：

● Factor analysis of ammonium nitrate formation based on thermodynamic theory.

关键词： Ammonium nitrate formation     Thermodynamic theory     Aerosol liquid water content     Source apportionment    

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Punching of reinforced concrete slab without shear reinforcement: Standard models and new proposal

Luisa PANI, Flavio STOCHINO

《结构与土木工程前沿（英文）》 2020年 第14卷 第5期   页码 1196-1214 doi: 10.1007/s11709-020-0662-z

摘要： Reinforced concrete (RC) slabs are characterized by reduced construction time, versatility, and easier space partitioning. Their structural behavior is not straightforward and, specifically, punching shear strength is a current research topic. In this study an experimental database of 113 RC slabs without shear reinforcement under punching loads was compiled using data available in the literature. A sensitivity analysis of the parameters involved in the punching shear strength assessment was conducted, which highlighted the importance of the flexural reinforcement that are not typically considered for punching shear strength. After a discussion of the current international standards, a new proposed model for punching shear strength and rotation of RC slabs without shear reinforcement was discussed. It was based on a simplified load-rotation curve and new failure criteria that takes into account the flexural reinforcement effects. This experimental database was used to validate the approaches of the current international standards as well as the new proposed model. The latter proved to be a potentially useful design tool.

关键词： punching shear strength     reinforced concrete     slabs     reinforcement ratio    

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The formation mechanism and the influence factor of residual stress in machining

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 265-269 doi: 10.1007/s11465-014-0311-0

摘要：

Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.

关键词： residual stress     analytical model     strain     plastic     cutting parameter    

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标题 作者 时间 类型 操作

High-precision standard enthalpy of formation for polycyclic aromatic hydrocarbons predicting from general

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

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

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

Time-varying formation tracking for uncertain second-order nonlinearmulti-agent systems

Mao-peng RAN, Li-hua XIE, Jun-cheng LI

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

3D finite element prediction of chip flow, burr formation, and cutting forces in micro end-milling of

A. DAVOUDINEJAD, P. PARENTI, M. ANNONI

期刊论文

Mechanistic insight into the biofilm formation and process performance of a passive aeration ditch (PAD

期刊论文

Is atmospheric oxidation capacity better in indicating tropospheric O formation?

期刊论文

Formation mechanism and modeling of surface waviness in incremental sheet forming

期刊论文

New insights into the formation of ammonium nitrate from a physical and chemical level perspective

期刊论文

Punching of reinforced concrete slab without shear reinforcement: Standard models and new proposal

Luisa PANI, Flavio STOCHINO

期刊论文

The formation mechanism and the influence factor of residual stress in machining

null

期刊论文