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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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Utilization of renewable energy in architectural design

TIAN Lei, QIN Youguo

《结构与土木工程前沿（英文）》 2007年第1卷第1期页码 114-122 doi: 10.1007/s11709-007-0012-4

摘要： Renewable energy does not simply equal to using a photovoltaic (PV) board. In addition to heating, ventilation and air conditioning (HVAC) engineering considerations, the design approaches of architects are crucial to the utilization condition and methods of renewable energy. Through profound comprehension of the relationship between renewableenergy utilization and design approaches, we can achieve a dual-standard of building environment performance and esthetics.

关键词： dual-standard photovoltaic relationship utilization environment performance

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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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A novel task-oriented framework for dual-arm robotic assembly task

《机械工程前沿（英文）》 2021年第16卷第3期页码 528-545 doi: 10.1007/s11465-021-0638-2

摘要： In industrial manufacturing, the deployment of dual-arm robots in assembly tasks has become a trend. However, making the dual-arm robots more intelligent in such applications is still an open, challenging issue. This paper proposes a novel framework that combines task-oriented motion planning with visual perception to facilitate robot deployment from perception to execution and finish assembly problems by using dual-arm robots. In this framework, visual perception is first employed to track the effects of the robot behaviors and observe states of the workpieces, where the performance of tasks can be abstracted as a high-level state for intelligent reasoning. The assembly task and manipulation sequences can be obtained by analyzing and reasoning the state transition trajectory of the environment as well as the workpieces. Next, the corresponding assembly manipulation can be generated and parameterized according to the differences between adjacent states by combining with the prebuilt knowledge of the scenarios. Experiments are set up with a dual-arm robotic system (ABB YuMi and an RGB-D camera) to validate the proposed framework. Experimental results demonstrate the effectiveness of the proposed framework and the promising value of its practical application.

关键词： dual-arm assembly AI reasoning intelligent system task-oriented motion planning visual perception

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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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Improved nitrogen removal in dual-contaminated surface water by photocatalysis

Yongming ZHANG, Rong YAN, Zhen ZOU, Jiewei WANG, Bruce E. RITTMANN

《环境科学与工程前沿（英文）》 2012年第6卷第3期页码 428-436 doi: 10.1007/s11783-012-0401-3

摘要： River waters in China have dual contamination by nutrients and recalcitrant organic compounds. In principle, the organic compounds could be used to drive denitrification of nitrate, thus arresting eutrophication potential, if the recalcitrant organics could be made bioavailable. This study investigated the potential to make the recalcitrant organics bioavailable through photocatalysis. Batch denitrification tests in a biofilm reactor demonstrated that dual-contaminated river water was short of available electron donor, which resulted in low total nitrogen (TN) removal by denitrification. However, the denitrification rate was increased significantly by adding glucose or by making the organic matters of the river water more bioavailable through photocatalysis. Photocatalysis for 15 min increased the Chemical Oxygen Demand (COD) of the river water from 53 to 84 mg·L and led to a 4-fold increase in TN removal. The increase in TN removal gave the same effect as adding 92 mg·L of glucose. During the photocatalysis experiments, the COD increased because photocatalysis transformed organic molecules from those that are resistant to dichromate oxidation in the COD test to those that can be oxidized by dichromate. This phenomenon was verified by testing photocatalysis of pyridine added to the river water. These findings point to the potential for N removal via denitrification after photocatalysis, and they also suggest that the rivers in China may be far more polluted than indicated by COD assays.

关键词： dual contamination eutrophication photocatalysis remediation surface water

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Development of a dual temperature control system for isoprene biosynthesis in

《化学科学与工程前沿（英文）》 2022年第16卷第7期页码 1079-1089 doi: 10.1007/s11705-021-2088-0

摘要： Conflict between cell growth and product accumulation is frequently encountered in the biosynthesis of secondary metabolites. To address the growth-production conflict in yeast strains harboring the isoprene synthetic pathway in the mitochondria, the dynamic control of isoprene biosynthesis was explored. A dual temperature regulation system was developed through engineering and expression regulation of the transcriptional activator Gal4p. A cold-sensitive mutant, Gal4ep19, was created by directed evolution of Gal4p based on an internally developed growth-based high-throughput screening method and expressed under the heat-shock promoter P_SSA4 to control the expression of P_GAL-driven pathway genes in the mitochondria. Compared to the control strain with constitutively expressed wild-type Gal4p, the dual temperature regulation strategy led to 34.5% and 72% improvements in cell growth and isoprene production, respectively. This study reports the creation of the first cold-sensitive variants of Gal4p by directed evolution and provides a dual temperature control system for yeast engineering that may also be conducive to the biosynthesis of other high-value natural products.

关键词： transcriptional activator directed evolution dynamic control heat-shock isoprene

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基于双CPU结构的数据监控系统设计

贾贵玺,齐乐

《中国工程科学》 2006年第8卷第4期页码 68-71

摘要：

针对通信系统中，对所有客户线路的电压、电流、温度等数据进行实时多路采集监控，提出了一种基于双CPU结构的数据监控系统的设计方法以及硬件组成。讨论了系统主要芯片之间的连线方法以及软件流程。该系统已经成功应用在邮电系统48V通信线路监控。实践证明，双CPU设计方案不仅满足了系统高运算量、高实时性、抗干扰性要求，而且优化了软硬件设计。

关键词：数据监控双CPU 双口RAM

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Experimental study of stratified lean burn characteristics on a dual injection gasoline engine

Chun XIA, Tingyu ZHAO, Junhua FANG, Lei ZHU, Zhen HUANG

《能源前沿（英文）》 2022年第16卷第6期页码 900-915 doi: 10.1007/s11708-021-0812-6

摘要： Due to increasingly stringent fuel consumption and emission regulation, improving thermal efficiency and reducing particulate matter emissions are two main issues for next generation gasoline engine. Lean burn mode could greatly reduce pumping loss and decrease the fuel consumption of gasoline engines, although the burning rate is decreased by higher diluted intake air. In this study, dual injection stratified combustion mode is used to accelerate the burning rate of lean burn by increasing the fuel concentration near the spark plug. The effects of engine control parameters such as the excess air coefficient (Lambda), direct injection (DI) ratio, spark interval with DI, and DI timing on combustion, fuel consumption, gaseous emissions, and particulate emissions of a dual injection gasoline engine are studied. It is shown that the lean burn limit can be extended to Lambda= 1.8 with a low compression ratio of 10, while the fuel consumption can be obviously improved at Lambda= 1.4. There exists a spark window for dual injection stratified lean burn mode, in which the spark timing has a weak effect on combustion. With optimization of the control parameters, the brake specific fuel consumption (BSFC) decreases 9.05% more than that of original stoichiometric combustion with DI as 2 bar brake mean effective pressure (BMEP) at a 2000 r/min engine speed. The NO_x emissions before three-way catalyst (TWC) are 71.31% lower than that of the original engine while the particle number (PN) is 81.45% lower than the original engine. The dual injection stratified lean burn has a wide range of applications which can effectively reduce fuel consumption and particulate emissions. The BSFC reduction rate is higher than 5% and the PN reduction rate is more than 50% with the speed lower than 2400 r/min and the load lower than 5 bar.

关键词： dual injection stratified lean burn gasoline engine particulate matter emission combustion analysis

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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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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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Effects of fuel combination and IVO timing on combustion and emissions of a dual-fuel HCCI combustion

Xin LIANG, Jianyong ZHANG, Zhongzhao LI, Jiabo ZHANG, Zhen HUANG, Dong HAN

《能源前沿（英文）》 2020年第14卷第4期页码 778-789 doi: 10.1007/s11708-020-0698-8

摘要： This paper experimentally and numerically studied the effects of fuel combination and intake valve opening (IVO) timing on combustion and emissions of an n-heptane and gasoline dual-fuel homogeneous charge compression ignition (HCCI) engine. By changing the gasoline fraction (GF) from 0.1 to 0.5 and the IVO timing from –15°CA ATDC to 35°CA ATDC, the in-cylinder pressure traces, heat release behaviors, and HC and CO emissions were investigated. The results showed that both the increased GF and the retarded IVO timing delay the combustion phasing, lengthen the combustion duration, and decrease the peak heat release rate and the maximum average combustion temperature, whereas the IVO timing has a more obvious influence on combustion than GF. HC and CO emissions are decreased with reduced GF, advanced IVO timing and increased operational load.

关键词： homogeneous charge compression ignition dual-fuel n-heptane gasoline intake valve opening timing