In allusion to the characteristics of the open complex giant system, an open multilevel hierarchic intelligent control system is established for the eco-industrial system. With the idea of the open engineering system,...In allusion to the characteristics of the open complex giant system, an open multilevel hierarchic intelligent control system is established for the eco-industrial system. With the idea of the open engineering system, using the hall for workshop of metasynthetic engineering (HWME), intelligent control techniques, the expert system and the design of experiments are integrated within the framework of the nonlinear multiobjective decision support system to develop a robust, top-level design specification so as to make the system have the quality of adaptive control, self-organizing, self-learning and robustness. Finally, an illustrative example is given to clarify the effectiveness of the method.展开更多
The mechanism of bolt support is an important topic in mining engineering and slope treatment. The artificial material and loading system were self-developed to study the influence of bedding cohesion and bolt number ...The mechanism of bolt support is an important topic in mining engineering and slope treatment. The artificial material and loading system were self-developed to study the influence of bedding cohesion and bolt number on the anchoring behavior of bedded rock mass. The results show that, both peak strength and elasticity modulus increase gradually with the increase of bedding cohesion and bolt number. The axial stress–strain curve of bedded rock mass under the reinforcement of bolts presents the features of strain-softening and secondary strengthening. Finally, anchoring behavior of bedded rock mass with different bolt numbers was simulated by using FLAC3 D numerical program and the results were compared with the experimental results. This study can provide certain bases to the stability control and support design of bedded rock mass in roadway.展开更多
The principles of the SINS/DVL integrated navigation system are introduced, and the compass status accuracy is compared. When the heading is changed, the dead reckoning algorithm using the heading information of the S...The principles of the SINS/DVL integrated navigation system are introduced, and the compass status accuracy is compared. When the heading is changed, the dead reckoning algorithm using the heading information of the SINS (Strapdown inertial navigation systems) and DVL (doppler velocity log) is adopted to substitute the SINS/DVL integrated system. The simulation results show that the method can improve the accuracy of integrated navigation system when AUV (autonomous underwater vehicle) is in motion.展开更多
An extended algorithm of flexibility analysis with a local adjusting method for flexibility region of chemical processes, which is based on the active constraint strategy, is proposed, which fully exploits the flexibi...An extended algorithm of flexibility analysis with a local adjusting method for flexibility region of chemical processes, which is based on the active constraint strategy, is proposed, which fully exploits the flexibility region of the process system operation. The hyperrectangular flexibility region determined by the extended algorithm is larger than that calculated by the previous algorithms. The limitation of the proposed algorithm due to imperfect convexity and its corresponding verification measure are also discussed. Both numerical and actual chemical process examples are presented to demonstrate the effectiveness of the new algorithm.展开更多
A growing number of three-dimensional(3D)-print- ing processes have been applied to tissue engineering. This paper presents a state-of-the-art study of 3D-printing technologies for tissue-engineering applications, wit...A growing number of three-dimensional(3D)-print- ing processes have been applied to tissue engineering. This paper presents a state-of-the-art study of 3D-printing technologies for tissue-engineering applications, with particular focus on the development of a computer-aided scaffold design system; the direct 3D printing of functionally graded scaffolds; the modeling of selective laser sintering(SLS) and fused deposition modeling(FDM) processes; the indirect additive manufacturing of scaffolds, with both micro and macro features; the development of a bioreactor; and 3D/4D bioprinting. Technological limitations will be discussed so as to highlight the possibility of future improvements for new 3D-printing methodologies for tissue engineering.展开更多
In the past, the probabilities of basic events were described as triangular or trapezoidal fuzzy number that cannot characterize the common distribution of the primary events in engineering, and the fault tree analyze...In the past, the probabilities of basic events were described as triangular or trapezoidal fuzzy number that cannot characterize the common distribution of the primary events in engineering, and the fault tree analyzed by fuzzy set theory did not include repeated basic events. This paper presents a new method to analyze the fault tree by using normal fuzzy number to describe the fuzzy probability of each basic event which is more suitably used to analyze the reliability in safety systems, and then the formulae of computing the fuzzy probability of the top event of the fault tree which includes repeated events are derived. Finally, an example is given.展开更多
A new method was proposed for tracking the desired output of chaotic dy- namical system using the feedback linearization and nonlinear extended statement ob- server method. The feedback linearization was used to conve...A new method was proposed for tracking the desired output of chaotic dy- namical system using the feedback linearization and nonlinear extended statement ob- server method. The feedback linearization was used to convert the nonlinear chaotic system into linear system. The extended Luenberger-like statements observer was de- signed to reconstructing and observing the unmeasured statements when the tracking controller was designed. By this way, the chaotic system could be forced to track vari- able desired output, which could be a time variant function or an equilibrium points. Taken the Lorenz chaotic system as example, the simulation results show the validity of the conclusion and effectiveness of the algorithm.展开更多
It is necessary to change the current dynamic of growth, to assure that future generations can satisfy their needs. Sustainable development and global sustainability are two concepts that have achieved great importanc...It is necessary to change the current dynamic of growth, to assure that future generations can satisfy their needs. Sustainable development and global sustainability are two concepts that have achieved great importance in almost every sector of activity. There is a wide range of methods and models for sustainability assessment. Nevertheless, it is necessary to go beyond evaluation, looking for sustainability optimization. In spite of this, little work has been done on the latter field. The authors present here a conceptual proposal for an integrated method to optimize sustainability of engineering systems, based on the MIVES (integrated value method for evaluating sustainability) method. For a better understanding of the method, its essential steps for optimizing an energy sub-system are summarized (shell-and-tube heat exchanger).展开更多
With the development of information technology, DSS can be used to resolve the complex process of the feasible reasoning and scientific decision-making of projects. This paper offers 7 exploiting principles for the co...With the development of information technology, DSS can be used to resolve the complex process of the feasible reasoning and scientific decision-making of projects. This paper offers 7 exploiting principles for the computer support system on feasible reasoning and scientific decision-making of projects, that is, the principles of standardization, procedure, specification, agility, currency, practicability and development. On the basis of analysis on systematic procedure, the computer support system on feasible reasoning and scientific decision-making of projects is formed based on WEB, and its general structure, system function and the methods to be realized are introduced. The data composition of this system is analyzed following the principles of integrality, development, perspicuity and consistency. Also, the model-base management system is designed for the management of model storage and management of model operation.展开更多
According to the rock engineering property and stability of high-steep open-pitslopes, various factors were collected on the basis of rock engineering system (RSE) theory,and the interaction matrix of stability evalua...According to the rock engineering property and stability of high-steep open-pitslopes, various factors were collected on the basis of rock engineering system (RSE) theory,and the interaction matrix of stability evaluation was established.Then, the stabilityevaluation index (S_p) of the slope was put forward.Ranges of the S_p value and the correspondingstable state were given on the basis of thirty-six samples.It is found that the followingrelationships exist: unstable (easy landslide): S_p<-0.20; mid-stable (may be landslide):-0.20<S_p<0.63; stable (no landslide): S_p>0.63.Finally, the stability evaluation indexwas applied on the high-steep open-pit slope of one mine.Analysis results and monitoringdata indicate that the index meets the necessity of the property of slope engineering, and ithas an important engineering purpose for landslide forecasting of high-steep slopes.展开更多
The construction industry in Botswana has been identified as an industry with many problems. Currently the Botswana government uses the design-bid-build process, using prequalification and awards to the lowest bidder ...The construction industry in Botswana has been identified as an industry with many problems. Currently the Botswana government uses the design-bid-build process, using prequalification and awards to the lowest bidder for construction services. The government can also use the design-build delivery system. The current delivery system uses an engineering group that delivers designs and construction, uses a procurement group to award the contract and contract modifications. However, the analysis for all actions is done by the engineering group. The model is very similar to the Corps of Engineers traditional processes in the United States. Construction performance (on time and no contract deviations) has not been good. The authors propose that the delivery system and the paradigm of direction, control and decision making by the engineering group causes risk to the project and results in poor contractor performance. The authors suggest making modifications in the process and to use the design-build process. The authors also propose to change the paradigm using best value PIPS/IMT concepts.展开更多
Surface tension of fluids is crucial for multiphase systems and is often controlled during industrial processes by introducing surfactants. In this study, effect of various microwave radiation modes on surface tension...Surface tension of fluids is crucial for multiphase systems and is often controlled during industrial processes by introducing surfactants. In this study, effect of various microwave radiation modes on surface tension of water was investigated as an alternative physical method to manipulate the surface tension without using chemicals. It is found that surface tension decreased quickly while temperature increased during microwave. Once the radiation was turned off, the temperature returned rapidly as expected. However, surface tension did not recover so much. The minimum surface tension after microwave radiation depended on the power. Moreover, a second radiation can have additional reduction on surface tension.展开更多
More than two decades ago, object-oriented representation of AEC (architecture engineering and construction) projects started to offer the promise of seamless communication of semantic data models between computer-b...More than two decades ago, object-oriented representation of AEC (architecture engineering and construction) projects started to offer the promise of seamless communication of semantic data models between computer-based systems used from the design stage to the operation of the facilities. BIM (building information modelling) emerged and appeared as a means to store all relevant data generated during the life-cycle of the facilities. But this upstream view of the built environment, arising from the design and construction stages, extended to the downstream operations where building and industrial facilities appeared more and more as huge dynamic data producers and concentrators while being operated. This created new challenges leading to what is referred to as ISCs (intelligent and smart constructions). The current state of the art is that final constructions still contain various and increasingly versatile control and service systems, which are hardly standardised, and not interconnected among themselves. Monitoring, maintenance and services are done by specialised companies, each responsible of different systems, which are relying on customised software and techniques to meet specific user needs and are based on monolithic applications that require manual configuration for specific uses, maintenance and support. We demonstrate in this paper that the early promises of integration across the actors and along the life-time of facilities have gone a long way but will only be delivered through enhanced standardisation of computerized models, representations, services and operations still not yet fully accomplished 25 years after work started.展开更多
The principal means of conserving water and utilizing hydropower in China is to exploit the use of a series of reservoirs in a cascade. This method and its inherent engineering safety problems are receiving increasing...The principal means of conserving water and utilizing hydropower in China is to exploit the use of a series of reservoirs in a cascade. This method and its inherent engineering safety problems are receiving increasing attention nowadays. In the field of engineering safety analysis, much work has focused on single reservoir projects in the past few years, but there is little research available on the safety risk analysis of cascade reservoirs, either within China or internationally. Therefore, a framework for risk analysis on the cascade reservoir system based on the theory of system engineering is constructed in this article. A cascading failure model is established and the connection degree factor discussed. In addition, the importance degree of the subsystem, which can be calculated by combining the analytical hierarchy process and the entropy weight method, is explained. According to brittleness theory of a complex system, brittle risk entropy is proposed as a performance index for measuring the collapse uncertainty of the cascade reservoir system. In addition, the brittle risk of the cascade reservoir system is predicted, which provides a reference for safety analysis in water conservation and hydropower construction projects in China.展开更多
With the integration of renewable energy generations and other related changes,the smart grid,or the future electric power system,is confronted with new challenges and opportunities.Therefore,it is a promising subject...With the integration of renewable energy generations and other related changes,the smart grid,or the future electric power system,is confronted with new challenges and opportunities.Therefore,it is a promising subject in electrical engineering and much work has been done on it.This paper reviews the recent advances on the technologies of smart grid and renewable energy integration,from the aspects of modeling,simulation,protection and control,stability,operation,and planning.展开更多
文摘In allusion to the characteristics of the open complex giant system, an open multilevel hierarchic intelligent control system is established for the eco-industrial system. With the idea of the open engineering system, using the hall for workshop of metasynthetic engineering (HWME), intelligent control techniques, the expert system and the design of experiments are integrated within the framework of the nonlinear multiobjective decision support system to develop a robust, top-level design specification so as to make the system have the quality of adaptive control, self-organizing, self-learning and robustness. Finally, an illustrative example is given to clarify the effectiveness of the method.
基金Financial provided by the National Key Research and Development Program of China (Grant No. 2017YFC0603001)the National Natural Science Foundation of China (Nos. 51734009 and 51704279)the Natural Science Foundation of Jiangsu Province (BK20170270)
文摘The mechanism of bolt support is an important topic in mining engineering and slope treatment. The artificial material and loading system were self-developed to study the influence of bedding cohesion and bolt number on the anchoring behavior of bedded rock mass. The results show that, both peak strength and elasticity modulus increase gradually with the increase of bedding cohesion and bolt number. The axial stress–strain curve of bedded rock mass under the reinforcement of bolts presents the features of strain-softening and secondary strengthening. Finally, anchoring behavior of bedded rock mass with different bolt numbers was simulated by using FLAC3 D numerical program and the results were compared with the experimental results. This study can provide certain bases to the stability control and support design of bedded rock mass in roadway.
文摘The principles of the SINS/DVL integrated navigation system are introduced, and the compass status accuracy is compared. When the heading is changed, the dead reckoning algorithm using the heading information of the SINS (Strapdown inertial navigation systems) and DVL (doppler velocity log) is adopted to substitute the SINS/DVL integrated system. The simulation results show that the method can improve the accuracy of integrated navigation system when AUV (autonomous underwater vehicle) is in motion.
文摘An extended algorithm of flexibility analysis with a local adjusting method for flexibility region of chemical processes, which is based on the active constraint strategy, is proposed, which fully exploits the flexibility region of the process system operation. The hyperrectangular flexibility region determined by the extended algorithm is larger than that calculated by the previous algorithms. The limitation of the proposed algorithm due to imperfect convexity and its corresponding verification measure are also discussed. Both numerical and actual chemical process examples are presented to demonstrate the effectiveness of the new algorithm.
基金Singapore National Research Foundation (NRF) for funding the Singapore Centre for 3D Printing (SC3DP)
文摘A growing number of three-dimensional(3D)-print- ing processes have been applied to tissue engineering. This paper presents a state-of-the-art study of 3D-printing technologies for tissue-engineering applications, with particular focus on the development of a computer-aided scaffold design system; the direct 3D printing of functionally graded scaffolds; the modeling of selective laser sintering(SLS) and fused deposition modeling(FDM) processes; the indirect additive manufacturing of scaffolds, with both micro and macro features; the development of a bioreactor; and 3D/4D bioprinting. Technological limitations will be discussed so as to highlight the possibility of future improvements for new 3D-printing methodologies for tissue engineering.
文摘In the past, the probabilities of basic events were described as triangular or trapezoidal fuzzy number that cannot characterize the common distribution of the primary events in engineering, and the fault tree analyzed by fuzzy set theory did not include repeated basic events. This paper presents a new method to analyze the fault tree by using normal fuzzy number to describe the fuzzy probability of each basic event which is more suitably used to analyze the reliability in safety systems, and then the formulae of computing the fuzzy probability of the top event of the fault tree which includes repeated events are derived. Finally, an example is given.
基金Supported by National Natural Science Foundation of China (60374013) and Natural Science Foundation of Zhejiang Province (Y104414, M603217)
文摘A new method was proposed for tracking the desired output of chaotic dy- namical system using the feedback linearization and nonlinear extended statement ob- server method. The feedback linearization was used to convert the nonlinear chaotic system into linear system. The extended Luenberger-like statements observer was de- signed to reconstructing and observing the unmeasured statements when the tracking controller was designed. By this way, the chaotic system could be forced to track vari- able desired output, which could be a time variant function or an equilibrium points. Taken the Lorenz chaotic system as example, the simulation results show the validity of the conclusion and effectiveness of the algorithm.
文摘It is necessary to change the current dynamic of growth, to assure that future generations can satisfy their needs. Sustainable development and global sustainability are two concepts that have achieved great importance in almost every sector of activity. There is a wide range of methods and models for sustainability assessment. Nevertheless, it is necessary to go beyond evaluation, looking for sustainability optimization. In spite of this, little work has been done on the latter field. The authors present here a conceptual proposal for an integrated method to optimize sustainability of engineering systems, based on the MIVES (integrated value method for evaluating sustainability) method. For a better understanding of the method, its essential steps for optimizing an energy sub-system are summarized (shell-and-tube heat exchanger).
文摘With the development of information technology, DSS can be used to resolve the complex process of the feasible reasoning and scientific decision-making of projects. This paper offers 7 exploiting principles for the computer support system on feasible reasoning and scientific decision-making of projects, that is, the principles of standardization, procedure, specification, agility, currency, practicability and development. On the basis of analysis on systematic procedure, the computer support system on feasible reasoning and scientific decision-making of projects is formed based on WEB, and its general structure, system function and the methods to be realized are introduced. The data composition of this system is analyzed following the principles of integrality, development, perspicuity and consistency. Also, the model-base management system is designed for the management of model storage and management of model operation.
基金Supported by the National Natural Science Foundation of China(50874042)
文摘According to the rock engineering property and stability of high-steep open-pitslopes, various factors were collected on the basis of rock engineering system (RSE) theory,and the interaction matrix of stability evaluation was established.Then, the stabilityevaluation index (S_p) of the slope was put forward.Ranges of the S_p value and the correspondingstable state were given on the basis of thirty-six samples.It is found that the followingrelationships exist: unstable (easy landslide): S_p<-0.20; mid-stable (may be landslide):-0.20<S_p<0.63; stable (no landslide): S_p>0.63.Finally, the stability evaluation indexwas applied on the high-steep open-pit slope of one mine.Analysis results and monitoringdata indicate that the index meets the necessity of the property of slope engineering, and ithas an important engineering purpose for landslide forecasting of high-steep slopes.
文摘The construction industry in Botswana has been identified as an industry with many problems. Currently the Botswana government uses the design-bid-build process, using prequalification and awards to the lowest bidder for construction services. The government can also use the design-build delivery system. The current delivery system uses an engineering group that delivers designs and construction, uses a procurement group to award the contract and contract modifications. However, the analysis for all actions is done by the engineering group. The model is very similar to the Corps of Engineers traditional processes in the United States. Construction performance (on time and no contract deviations) has not been good. The authors propose that the delivery system and the paradigm of direction, control and decision making by the engineering group causes risk to the project and results in poor contractor performance. The authors suggest making modifications in the process and to use the design-build process. The authors also propose to change the paradigm using best value PIPS/IMT concepts.
文摘Surface tension of fluids is crucial for multiphase systems and is often controlled during industrial processes by introducing surfactants. In this study, effect of various microwave radiation modes on surface tension of water was investigated as an alternative physical method to manipulate the surface tension without using chemicals. It is found that surface tension decreased quickly while temperature increased during microwave. Once the radiation was turned off, the temperature returned rapidly as expected. However, surface tension did not recover so much. The minimum surface tension after microwave radiation depended on the power. Moreover, a second radiation can have additional reduction on surface tension.
文摘More than two decades ago, object-oriented representation of AEC (architecture engineering and construction) projects started to offer the promise of seamless communication of semantic data models between computer-based systems used from the design stage to the operation of the facilities. BIM (building information modelling) emerged and appeared as a means to store all relevant data generated during the life-cycle of the facilities. But this upstream view of the built environment, arising from the design and construction stages, extended to the downstream operations where building and industrial facilities appeared more and more as huge dynamic data producers and concentrators while being operated. This created new challenges leading to what is referred to as ISCs (intelligent and smart constructions). The current state of the art is that final constructions still contain various and increasingly versatile control and service systems, which are hardly standardised, and not interconnected among themselves. Monitoring, maintenance and services are done by specialised companies, each responsible of different systems, which are relying on customised software and techniques to meet specific user needs and are based on monolithic applications that require manual configuration for specific uses, maintenance and support. We demonstrate in this paper that the early promises of integration across the actors and along the life-time of facilities have gone a long way but will only be delivered through enhanced standardisation of computerized models, representations, services and operations still not yet fully accomplished 25 years after work started.
基金supported by the National Science and Technology Plan(Grant No.2013BAB06B01)the Graduate Student Scientific Research Innovation Projects of Regular Institutions of Jiangsu Province(Grant Nos.CXZZ11_0439&CXZZ13_0236)
文摘The principal means of conserving water and utilizing hydropower in China is to exploit the use of a series of reservoirs in a cascade. This method and its inherent engineering safety problems are receiving increasing attention nowadays. In the field of engineering safety analysis, much work has focused on single reservoir projects in the past few years, but there is little research available on the safety risk analysis of cascade reservoirs, either within China or internationally. Therefore, a framework for risk analysis on the cascade reservoir system based on the theory of system engineering is constructed in this article. A cascading failure model is established and the connection degree factor discussed. In addition, the importance degree of the subsystem, which can be calculated by combining the analytical hierarchy process and the entropy weight method, is explained. According to brittleness theory of a complex system, brittle risk entropy is proposed as a performance index for measuring the collapse uncertainty of the cascade reservoir system. In addition, the brittle risk of the cascade reservoir system is predicted, which provides a reference for safety analysis in water conservation and hydropower construction projects in China.
基金supported by the National Natural Science Foundation of China(Grant Nos.51321005,51207076)the National High Technology Research and Development of China("863" Project)(Grant No.2012AA050204)
文摘With the integration of renewable energy generations and other related changes,the smart grid,or the future electric power system,is confronted with new challenges and opportunities.Therefore,it is a promising subject in electrical engineering and much work has been done on it.This paper reviews the recent advances on the technologies of smart grid and renewable energy integration,from the aspects of modeling,simulation,protection and control,stability,operation,and planning.