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Self-generation of machining precision and its realization in lapping of super precision solid balls

ZHANG Bopeng

《机械工程前沿（英文）》 2008年 第3卷 第3期   页码 348-353 doi: 10.1007/s11465-008-0065-7

摘要： This paper presents the principle of self-generation of machining precision by explaining its basic concept and five necessary conditions for forming a system with self-organization capability. A self-generation system is a kind of system with self-organization capability. The self-generation of machining precision for solid balls with super precision is emphatically explained. From the viewpoint of self-organization, there are three types of systems including system 1 with the self-regulation capability, 2 with the self-determination capability of goals, and 3 with the self-organization capability. Although they are all closed loop control systems, they have different constructions and functions. Necessary conditions for achieving self-generation of machining precision are given. Establishment of the system for machining solid balls with super precision is discussed. Self-generation of machining precision for solid balls with super precision on the basis of the capability of self-removal of errors is presented. Self-generation includes the ability of self-removal of errors for solid balls, convergence of self-removal of errors, self-generation of precision, and self-generating system for the given.

关键词： self-generation     necessary     self-regulation capability     viewpoint     Necessary    

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Climate change and its consequences for water and wastewater management

Peter A. WILDERER

《环境科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 1-1 doi: 10.1007/s11783-009-0001-z

摘要： Life, in combination with solar radiation and abiotic processes, is most probably the reason why liquid water has existed on Earth for over billions of years, and the global mean temperature has remained in a life-enabling range. Efforts to limit or even reverse global warming must be derived from the knowledge of the Earth’s complex life-support system. In this context, the balance between liquid and gaseous water plays a crucial role, and water management becomes an important field of innovation and action, globally, on the scale of watersheds but also on the very local level. Cascading use, reuse, and temporary storage of water in urban settings must be considered to limit over-extraction of water from natural resources, and to maintain the life supporting function of ecosystems. At the same time, public health requirements, cost efficiency, and reliability demands are to be met.

关键词： ecosystem     management tools     self-regulation     urbanization     water-climate relationship     water reuse    

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Design and experimental study of a passive power-source-free stiffness-self-adjustable mechanism

Yuwang LIU, Dongqi WANG, Shangkui YANG, Jinguo LIU, Guangbo HAO

《机械工程前沿（英文）》 2021年 第16卷 第1期   页码 32-45 doi: 10.1007/s11465-020-0604-4

摘要： Passive variable stiffness joints have unique advantages over active variable stiffness joints and are currently eliciting increased attention. Existing passive variable stiffness joints rely mainly on sensors and special control algorithms, resulting in a bandwidth-limited response speed of the joint. We propose a new passive power-source-free stiffness-self-adjustable mechanism that can be used as the elbow joint of a robot arm. The new mechanism does not require special stiffness regulating motors or sensors and can realize large-range self-adaptive adjustment of stiffness in a purely mechanical manner. The variable stiffness mechanism can automatically adjust joint stiffness in accordance with the magnitude of the payload, and this adjustment is a successful imitation of the stiffness adjustment characteristics of the human elbow. The response speed is high because sensors and control algorithms are not needed. The variable stiffness principle is explained, and the design of the variable stiffness mechanism is analyzed. A prototype is fabricated, and the associated hardware is set up to validate the analytical stiffness model and design experimentally.

关键词： variable stiffness mechanism     stiffness self-regulation     bionic robot     modeling    

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Radial electromagnetic type unbalance vibration self-recovery regulation system for high-end grinding

《机械工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0763-1

摘要： Modern rotating machines, which are represented by high-end grinding machines, have developed toward high precision, intelligence, and high durability in recent years. As the core components of grinding machine spindles, grinding wheels greatly affect the vibration level during operation. The unbalance vibration self-recovery regulation (UVSRR) system is proposed to suppress the vibration of grinding wheels during workpiece processing, eliminating or minimizing the imbalance. First, technical principles and the system composition are introduced. Second, the balancing actuator in the UVSRR system is analyzed in detail. The advanced nature of the improved structure is presented through structure introduction and advantage analysis. The performance of the balancing actuator is mutually verified by the theoretical calculation of torque and software simulation. Results show that the self-locking torque satisfies the actual demand, and the driving torque is increased by 1.73 times compared with the traditional structure. Finally, the engineering application value of the UVSRR system is verified by laboratory performance comparison and actual factory application. The balancing speed and effect of the UVSRR system are better than those of an international mainstream product and, the quality of the workpieces machined in the factory improved by 40%.

关键词： UVSRR system     radial electromagnetic type     vibration suppression     performance simulation     engineering application    

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装备系统故障自愈原理研究

高金吉

《中国工程科学》 2005年 第7卷 第5期   页码 43-48

摘要：

装备故障可否在其运行中得到控制或自行消除？故障能否像人和动物的疾病一样可以“自愈”？在系统科学的指导下，移植现代医学“自主调理”治疗原理，包括免疫、防御、代偿、自修复和适应等，可以用来指导研究装备自愈原理及工程应用；重点研究了以故障预防和消除为目标的装备系统自愈调控原理，为研制出具有自愈功能的新一代装备提供科学依据。

关键词： 装备系统     故障自愈原理     故障自愈调控     诊断     主动控制    

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SALL4 maintains self-renewal of porcine pluripotent stem cells through downregulation of OTX2

Ning WANG, Sile WANG, Yaxian WANG, Yuanxing CAI, Fan YANG, Huayan WANG

《农业科学与工程前沿（英文）》 2019年 第6卷 第1期   页码 81-92 doi: 10.15302/J-FASE-2017180

摘要：

Sall4 as one of the spalt family members contains several alternative splicing variants, which are differentially expressed and has a key role in maintaining pluripotent stem cells. However, the molecular features and function of SALL4 have not been well elucidated in porcine induced pluripotent stem cells (piPSCs). In this study, we identified splice variants and found two splicing variants through analysis of the porcine transcriptome data derived from piPSCs. SALL4A was only detected in piPSCs but SALL4B was globally expressed in porcine tissues and piPSCs. The level of SALL4B was significantly reduced when piPSCs differentiation occurred, however, the expression of SALL4A was not affected, indicating that SALL4B may be essential for the maintenance of piPSCs self-renewal. Overexpression of SALL4A and SALL4B in PEF cells could significantly stimulated expression of endogenous pluripotent genes, when SALL4B significantly promoted OCT4 expression. Conversely, SALL4A significantly promoted KLF4 expression. Additionally, both SALL4A and SALL4B could repress promoter activity in a dose-dependent manner. Conversely, OTX2 also negatively regulated SALL4 expression. These observations indicate that a negative feedback regulatory mechanism may exist between SALL4 and OTX2, which is useful for the maintenance of the self-renewal of piPSCs.

关键词： OTX2     pluripotency     pig     SALL4     transcription regulation    

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Moving policy and regulation forward for single-use plastic alternatives

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1423-5

摘要： Single-use plastics are often used once or cannot be reused for extended periods. They are widely consumed with the rapid development of social economy. The waste generated by single-use plastics threatens ecosystem health by entering the environment and ultimately restricts sustainable human development. The innovation of sustainable and environmentally friendly single-use plastic alternative materials and the joint participation of governments, enterprises and the public are promising technologies and management approaches that can solve the problem of single-use plastics wastes. The development of single-use plastic alternative products can be promoted fundamentally only by improving relevant legislation and standards, providing differentiated industrial policies, encouraging scientific and technological innovation and expanding public participation.

关键词： Single-use plastic alternatives     Policy     Regulation     Sustainable development    

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Phase transition regulation and caloric effect

《能源前沿（英文）》 2023年 第17卷 第4期   页码 463-477 doi: 10.1007/s11708-023-0860-1

摘要： Solid state refrigeration based on caloric effect is regarded as a potential candidate for replacing vapor-compression refrigeration. Numerous methods have been proposed to optimize the refrigeration properties of caloric materials, of which single field tuning as a relatively simple way has been systemically studied. However, single field tuning with few tunable parameters usually obtains an excellent performance in one specific aspect at the cost of worsening the performance in other aspects, like attaining a large caloric effect with narrowing the transition temperature range and introducing hysteresis. Because of the shortcomings of the caloric effect driven by a single field, multifield tuning on multicaloric materials that have a coupling between different ferro-orders came into view. This review mainly focuses on recent studies that apply this method to improve the cooling performance of materials, consisting of enlarging caloric effects, reducing hysteresis losses, adjusting transition temperatures, and widening transition temperature spans, which indicate that further progress can be made in the application of this method. Furthermore, research on the sign of lattice and spin contributions to the magnetocaloric effect found new phonon evolution mechanisms, calling for more attention on multicaloric effects. Other progress including improving cyclability of FeRh alloys by introducing second phases and realizing a large reversible barocaloric effect by hybridizing carbon chains and inorganic groups is described in brief.

关键词： phase transition regulation     caloric effect     solid state refrigeration    

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Understanding the influencing factors and evolving trends of the Yellow River Water-Sediment Regulation

《工程管理前沿（英文）》 doi: 10.1007/s42524-024-0304-6

摘要： Understanding the influencing factors and the evolving trends of the Water-Sediment Regulation System (WSRS) is vital for the protection and management of the Yellow River. Past studies on WSRS have been limited in focus and have not fully addressed the complete engineering control system of the basin. This study takes a holistic view, treating sediment management in the Yellow River as a dynamic and ever-evolving complex system. It merges concepts from system science, information theory, and dissipative structure with practical efforts in sediment engineering control. The key findings of this study are as follows: between 1990 and 2019, the average Yellow River Sediment Regulation Index (YSRI) was 55.99, with the lowest being 50.26 in 1990 and the highest being 61.48 in 2019; the result indicates that the WSRS activity decreased, yet it fluctuated, gradually approaching the critical threshold of a dissipative structure.

关键词： Yellow River     Water-Sediment Regulation System     Yellow River Sediment Regulation Index     system perspective     sustainable management.    

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The function and regulation of OTU deubiquitinases

Jiansen Du, Lin Fu, Yingli Sui, Lingqiang Zhang

《医学前沿（英文）》 2020年 第14卷 第5期   页码 542-563 doi: 10.1007/s11684-019-0734-4

摘要： Post-translational modification of cellular proteins by ubiquitin regulates numerous cellular processes, including cell division, immune responses, and apoptosis. Ubiquitin-mediated control over these processes can be reversed by deubiquitinases (DUBs), which remove ubiquitin from target proteins and depolymerize polyubiquitin chains. Recently, much progress has been made in the DUBs. In humans, the ovarian tumor protease (OTU) subfamily of DUBs includes 16 members, most of which mediate cell signaling cascades. These OTUs show great variation in structure and function, which display a series of mechanistic features. In this review, we provide a comprehensive analysis of current progress in character, structure and function of OTUs, such as the substrate specificity and catalytic activity regulation. Then we discuss the relationship between some diseases and OTUs. Finally, we summarize the structure of viral OTUs and their function in immune escape and viral survival. Despite the challenges, OTUs might provide new therapeutic targets, due to their involvement in key regulatory processes.

关键词： ubiquitin     OTU deubiquitinases     structure     function     regulation    

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Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

《农业科学与工程前沿（英文）》 2016年 第3卷 第3期   页码 186-194 doi: 10.15302/J-FASE-2016107

摘要： As an important oil crop and a potential bioenergy crop, L. is becoming a model plant for basic research on seed lipid biosynthesis as well as seed oil content, which has always been the key breeding objective. In this review, we present current progress in understanding of the regulation of oil content in , including genetics, biosynthesis pathway, transcriptional regulation, maternal effects and QTL analysis. Furthermore, the history of breeding for high oil content in is summarized and the progress in breeding ultra-high oil content lines is described. Finally, prospects for breeding high oil content cultivars are outlined.

关键词： breeding     maternal effects     oilseed rape     QTL    

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Regulation of exogenous bFGF gene mediated by recombinant adeno-associated virus

Ke SONG, Nianjing RAO, Meiling CHEN, Yingguang CAO

《医学前沿（英文）》 2009年 第3卷 第2期   页码 158-163 doi: 10.1007/s11684-009-0042-5

摘要： The regulatory effect of basic fibroblast growth factor (bFGF) mediated by recombinant adeno-associated virus (AAV) was investigated. Recombinant plasmid pAAV-S3-bFGF, and pSVneo were co-transfected into BHK-21 cells, then the recombinant AAV genome was replicated and packaged with the helper virus HSV1-rc/ΔUL2. The titer of the recombinant rAAV2-tet-off-bFGF was determined by dot-blot assay. MC3T3-E1 cells were infected with rAAV2-tet-off-bFGF. Regulatory effects of Doxycycline (Dox) on bFGF and osteogenic factors were assayed quantitatively by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The physical particle titer of rAAV2-tet-off-bFGF successfully constructed was 1.8×10 vector genomes/mL, and the virus could infect MC3T3-E1 cells effectively. In MC3T3-E1 cells treated with Dox, the expression levels of exogenous bFGF and osteogenic factors declined to varying degrees. It was concluded that rAAV2-tet-off-bFGF could infect MC3T3 cells efficiently, and this recombinant system could be regulated successfully by Dox .

关键词： tetracycline regulatory system     adeno-associated virus     basic fibroblast growth factor     gene regulation    

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RECENT ADVANCES IN THE REGULATION OF CLIMACTERIC FRUIT RIPENING: HORMONE, TRANSCRIPTION FACTOR AND EPIGENETIC

《农业科学与工程前沿（英文）》 2021年 第8卷 第2期

摘要：

Fruit ripening is a complex developmental process made up of genetically programmed physiological and biochemical activities. It culminates in desirable changes in the structural and textural properties and is governed by a complex regulatory network. Much is known about ethylene, one of the most important metabolites promoting the ripening of climacteric fruits. However, the dynamic interplay between phytohormones also plays an important part. Additional regulatory factors such as transcription factors (TFs) and epigenetic modifications also play vital role in the regulation of climacteric fruit ripening. Here, we review and evaluate the complex regulatory network comprising interactions between hormones and the action of TFs and epigenetic modifications during climacteric fruit ripening.

 

关键词： climacteric fruit ripening / phytohormones / TFs / epigenetic modifications    

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Exploring self-organization and self-adaption for smart manufacturing complex networks

《工程管理前沿（英文）》 2023年 第10卷 第2期   页码 206-222 doi: 10.1007/s42524-022-0225-1

摘要： Trends toward the globalization of the manufacturing industry and the increasing demands for small-batch, short-cycle, and highly customized products result in complexities and fluctuations in both external and internal manufacturing environments, which poses great challenges to manufacturing enterprises. Fortunately, recent advances in the Industrial Internet of Things (IIoT) and the widespread use of embedded processors and sensors in factories enable collecting real-time manufacturing status data and building cyber–physical systems for smart, flexible, and resilient manufacturing systems. In this context, this paper investigates the mechanisms and methodology of self-organization and self-adaption to tackle exceptions and disturbances in discrete manufacturing processes. Specifically, a general model of smart manufacturing complex networks is constructed using scale-free networks to interconnect heterogeneous manufacturing resources represented by network vertices at multiple levels. Moreover, the capabilities of physical manufacturing resources are encapsulated into virtual manufacturing services using cloud technology, which can be added to or removed from the networks in a plug-and-play manner. Materials, information, and financial assets are passed through interactive links across the networks. Subsequently, analytical target cascading is used to formulate the processes of self-organizing optimal configuration and self-adaptive collaborative control for multilevel key manufacturing resources while particle swarm optimization is used to solve local problems on network vertices. Consequently, an industrial case based on a Chinese engine factory demonstrates the feasibility and efficiency of the proposed model and method in handling typical exceptions. The simulation results show that the proposed mechanism and method outperform the event-triggered rescheduling method, reducing manufacturing cost, manufacturing time, waiting time, and energy consumption, with reasonable computational time. This work potentially enables managers and practitioners to implement active perception, active response, self-organization, and self-adaption solutions in discrete manufacturing enterprises.

关键词： cyber–physical systems     Industrial Internet of Things     smart manufacturing complex networks     self-organization and self-adaption     analytical target cascading     collaborative optimization    

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Simulation analysis of pressure regulation of hydraulic thrust system on a shield tunneling machine

Zhibin LIU, Haibo XIE, Huayong YANG

《机械工程前沿（英文）》 2011年 第6卷 第3期   页码 377-382 doi: 10.1007/s11465-011-0226-y

摘要：

Hydraulic thrust system is an important system in a shield tunneling machine. Pressure regulation of thrust cylinders is the most important function for thrust system during tunnel excavation. In this paper, a hydraulic thrust system is explained, and a corresponding simulation model is carried out in order to study the system characteristics. Pressure regulation of a certain group’s cylinders has little influence on regulation of the other groups’ cylinders. The influence will not affect the process much during tunnel excavation. Pump displacement may have a greater effect on pressure regulation and oil supply flow rate should be adaptive to the system’s demand. A exacting situation is simulated to explain how pressure regulation works during tunnel excavation.

关键词： tunnel     hydraulic thrust system     pressure regulation     simulation    

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标题 作者 时间 类型 操作

Self-generation of machining precision and its realization in lapping of super precision solid balls

ZHANG Bopeng

期刊论文

Climate change and its consequences for water and wastewater management

Peter A. WILDERER

期刊论文

Design and experimental study of a passive power-source-free stiffness-self-adjustable mechanism

Yuwang LIU, Dongqi WANG, Shangkui YANG, Jinguo LIU, Guangbo HAO

期刊论文

Radial electromagnetic type unbalance vibration self-recovery regulation system for high-end grinding

期刊论文

装备系统故障自愈原理研究

高金吉

期刊论文

SALL4 maintains self-renewal of porcine pluripotent stem cells through downregulation of OTX2

Ning WANG, Sile WANG, Yaxian WANG, Yuanxing CAI, Fan YANG, Huayan WANG

期刊论文

Moving policy and regulation forward for single-use plastic alternatives

期刊论文

Phase transition regulation and caloric effect

期刊论文

Understanding the influencing factors and evolving trends of the Yellow River Water-Sediment Regulation

期刊论文

The function and regulation of OTU deubiquitinases

Jiansen Du, Lin Fu, Yingli Sui, Lingqiang Zhang

期刊论文

Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

期刊论文

Regulation of exogenous bFGF gene mediated by recombinant adeno-associated virus

Ke SONG, Nianjing RAO, Meiling CHEN, Yingguang CAO

期刊论文

RECENT ADVANCES IN THE REGULATION OF CLIMACTERIC FRUIT RIPENING: HORMONE, TRANSCRIPTION FACTOR AND EPIGENETIC

期刊论文

Exploring self-organization and self-adaption for smart manufacturing complex networks

期刊论文

Simulation analysis of pressure regulation of hydraulic thrust system on a shield tunneling machine

Zhibin LIU, Haibo XIE, Huayong YANG

期刊论文