SOZL (structured methodology + object-oriented methodology + Z language) is a language that attempts to integrate structured method, object-oriented method and formal method. The core of this language is predicate dat...SOZL (structured methodology + object-oriented methodology + Z language) is a language that attempts to integrate structured method, object-oriented method and formal method. The core of this language is predicate data flow diagram (PDFD). In order to eliminate the ambiguity of predicate data flow diagrams and their associated textual specifications, a formalization of the syntax and semantics of predicate data flow diagrams is necessary. In this paper we use Z notation to define an abstract syntax and the related structural constraints for the PDFD notation, and provide it with an axiomatic semantics based on the concept of data availability and functionality of predicate operation. Finally, an example is given to establish functionality consistent decomposition on hierarchical PDFD (HPDFD).展开更多
In this paper,the heat flow diagram of steam turbine model K-6-35 has been analyzed for innovative approaches towards improving the techno-economic and ecological indices of the small-scale power generation system.The...In this paper,the heat flow diagram of steam turbine model K-6-35 has been analyzed for innovative approaches towards improving the techno-economic and ecological indices of the small-scale power generation system.The numerical analysis is performed using IPSEpro process simulation software based on heat balance method under four different cases.It was found that the study of Solar Assisted Power Generation(SAPG)system has important practical significance in power generation with minimum pollutants and maximum efficiency.Both fuel-saving(FS)and power-boosting(PB)operation modes of the SAPG system are considered.Various types of stand-alone solar thermal power plants exhibited very low overall efficiency with many ecological advantages compared to the conventional thermal power plant based on fossil fuels.Besides,SAPG system with FS mode presented higher techno-economic indices and operation performance.An important reduction in fuel consumption and pollutant emissions could be obtained with SAPG system.Considering the hourly,daily,monthly,and yearly amount of saved fuel and reduced pollutants in the whole power plant,the SAPG system with FS mode can largely contribute to high ecological indices power generation.A thermal efficiency increased by 1.31%with specific equivalent fuel consumption decreased by 22.54 g/kWh was obtained with SAPG system.The coal consumption was reduced by 4.75%when SAPG system operates in FS mode.展开更多
A new synthetical knowledge representation model that integrates the attribute grammar model with the semantic network model was presented. The model mainly uses symbols of attribute grammar to establish a set of sy...A new synthetical knowledge representation model that integrates the attribute grammar model with the semantic network model was presented. The model mainly uses symbols of attribute grammar to establish a set of syntax and semantic rules suitable for a semantic network. Based on the model,the paper introduces a formal method defining data flow diagrams (DFD) and also simply explains how to use the method.展开更多
Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimina...Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimination diagrams fail to correctly classify them,i.e.many mafic展开更多
Pedestrian flow parameters are analysed in this study considering linear and non-linear relationships between stream flow parameters using conventional and soft computing approach. Speed-density relationship serves as...Pedestrian flow parameters are analysed in this study considering linear and non-linear relationships between stream flow parameters using conventional and soft computing approach. Speed-density relationship serves as a fundamental relationship, Single-regime con- cepts and deterministic models like Greenshield and Underwood were applied in the study to describe bidirec- tional flow characteristics on sidewalks and carriageways around transport terminals in India. Artificial Neural Net- work (ANN) approach is also used for traffic flow mod- elling to build a relationship between different pedestrian flow parameters. A non-linear model based on ANN is suggested and compared with the other deterministic models. Out of the aforesaid models, ANN model demonstrated good results based on accuracy measure- ment. Also these ANN models have an advantage in terms of their self-processing and intelligent behaviour. Flow parameters are estimated by ANN model using MFD (Macroscopic Fundamental Diagram). Estimated mean absolute error (MAE) and root mean square error (RMSE)values for the best fitted ANN model are 3.83 and 4.73 m/ min, respectively, less than those for the other models for sidewalk movement. Further estimated MAE and RMSE values of ANN model for carriageway movement are 4.02 and 4.98 m/min, respectively, which are comparatively less than those of the other models. ANN model gives better performance in fitness of model and future prediction of flow parameters. Also when using linear regression model between observed and estimated values for speed and flow parameters, performance of ANN model gives better fitness to predict data as compared to deterministic model. R value for speed data prediction is 0.756 and for flow data pre- diction is 0.997 using ANN model at sidewalk movement around transport terminal.展开更多
针对航天嵌入式软件(aerospace embedded software,AES)时序需求复杂带来的时序需求定义不准确问题,提出一种基于MARTE(modeling and analysis of real-time and embedded systems)模型的数据流时序(data flow timing based on MARTE,DF...针对航天嵌入式软件(aerospace embedded software,AES)时序需求复杂带来的时序需求定义不准确问题,提出一种基于MARTE(modeling and analysis of real-time and embedded systems)模型的数据流时序(data flow timing based on MARTE,DFT-MARTE)模型,设计基于该模型的处理点缓存计算算法、时序偏离概率检测算法和时序序列分析算法。处理点缓存计算算法动态更新缓存空间,使后续时序检测正常执行;时序偏离概率检测算法利用多线程并发模拟时序特性,检测需求中时序偏离问题;时序序列分析算法是基于梯度下降算法,拟合时序序列,指导用户优化需求。该模型相比传统数据流模型更适用航天嵌入式软件,利于后续开发和维护,具有极高的应用价值。展开更多
The Moody Diagram is widely used to determine the friction factor for fluid flow in pipes. The diagram combines the effects of Reynolds number and relative roughness to determine the friction factor. The relationship ...The Moody Diagram is widely used to determine the friction factor for fluid flow in pipes. The diagram combines the effects of Reynolds number and relative roughness to determine the friction factor. The relationship is highly non-linear and appears to have a complex interaction between viscous and boundary roughness effects. The Moody Diagram is based on predictions from an equation developed by Colebrook in 1939. The relationship requires an iteration process to make predictions. While empirical relationships have been developed that provide good predictions without an iteration process, no one has fully explained the cause for the observed results. The objective of this paper is to present a logical development for prediction of the friction factor. An equation has been developed that models the summed effect of both the laminar sublayer and the boundary roughness on the fluid profile and the resulting friction factor for pipes. The new equation does not require an iteration procedure to obtain values for the friction factor. Predicted results match well with values generated from Colebrook’s work that is expressed in the Moody Diagram. Predictions are within one percent of Colebrook values and generally less than 0.3 percent error from his values. The development provides insight to how processes operating at the boundary cause the friction factor to change.展开更多
The shear-thinning/thickening effects on the plane Couette-Poiseuille flow with a uniform crossflow are studied. The detailed solution procedures for both theo- retical and numerical purposes are given. In order to cl...The shear-thinning/thickening effects on the plane Couette-Poiseuille flow with a uniform crossflow are studied. The detailed solution procedures for both theo- retical and numerical purposes are given. In order to clarify the difference between the Newtonian flow and the power-law flow, all cases of the plane Couette-Poiseuille flows with uniform crossflows for different power indexes are assigned to the phase diagram in the parameter plane corresponding to the Couette number and the crossflow Reynolds number. The effects of shear-thinning/thickening on the phase diagram are discussed. An important feature of the shear-thinning circumstance distinguished from the shear- thickening circumstance is discovered.展开更多
Intense human activities have greatly changed the flood generation conditions in most areas of the world, and have destroyed the consistency in the annual flood peak and volume series. For design flood estimation, coa...Intense human activities have greatly changed the flood generation conditions in most areas of the world, and have destroyed the consistency in the annual flood peak and volume series. For design flood estimation, coaxial correlation diagram and conceptual hydrological model are two frequently used tools to adjust and reconstruct the flood series under human disturbance. This study took a typical mountain catchment of the Haihe River Basin as an example to investigate the effects of human activities on flood regime and to compare and assess the two adjustment methods. The main purpose is to construct a conceptual hydrological model which can incorporate the effects of human activities. The results show that the coaxial correlation diagram is simple and widely-used, but can only adjust the time series of total flood volumes. Therefore, it is only applicable under certain conditions(e.g. There is a strong link between the flood peaks and volumes and the link is not significantly affected by human activities). The conceptual model is a powerful tool to adjust the time series of both flood peak flows and flood volumes over different durations provided that it is closely related to the catchment hydrological characteristics, specifically accounting for the effects of human activities, and incorporating expert knowledge when estimating or calibrating parameters. It is suggested that the two methods should be used together to cross check each other.展开更多
The “Citizen-Centric Complaint Reporting and Analyzing Mechanism” project is designed to create an online complaint system, called “e-Complaint”, to allow citizens to file complaints related to crime and misconduc...The “Citizen-Centric Complaint Reporting and Analyzing Mechanism” project is designed to create an online complaint system, called “e-Complaint”, to allow citizens to file complaints related to crime and misconduct in a secure and user-friendly way. The proposed system aims to address the challenges of the current complaint system, ensuring transparency and accountability in the police force. The “e-Complaint” system aims to increase police accountability and transparency and has significant benefits for both citizens and police departments.展开更多
文摘SOZL (structured methodology + object-oriented methodology + Z language) is a language that attempts to integrate structured method, object-oriented method and formal method. The core of this language is predicate data flow diagram (PDFD). In order to eliminate the ambiguity of predicate data flow diagrams and their associated textual specifications, a formalization of the syntax and semantics of predicate data flow diagrams is necessary. In this paper we use Z notation to define an abstract syntax and the related structural constraints for the PDFD notation, and provide it with an axiomatic semantics based on the concept of data availability and functionality of predicate operation. Finally, an example is given to establish functionality consistent decomposition on hierarchical PDFD (HPDFD).
基金This work was supported by the China National Key Research and Development Plan Project(Grant No.2018YFA0702300)the National Natural Science Foundation of China(Grant No.51522601)and the China Postdoctoral Science Foundation Fund(Grant No.2019M651284).
文摘In this paper,the heat flow diagram of steam turbine model K-6-35 has been analyzed for innovative approaches towards improving the techno-economic and ecological indices of the small-scale power generation system.The numerical analysis is performed using IPSEpro process simulation software based on heat balance method under four different cases.It was found that the study of Solar Assisted Power Generation(SAPG)system has important practical significance in power generation with minimum pollutants and maximum efficiency.Both fuel-saving(FS)and power-boosting(PB)operation modes of the SAPG system are considered.Various types of stand-alone solar thermal power plants exhibited very low overall efficiency with many ecological advantages compared to the conventional thermal power plant based on fossil fuels.Besides,SAPG system with FS mode presented higher techno-economic indices and operation performance.An important reduction in fuel consumption and pollutant emissions could be obtained with SAPG system.Considering the hourly,daily,monthly,and yearly amount of saved fuel and reduced pollutants in the whole power plant,the SAPG system with FS mode can largely contribute to high ecological indices power generation.A thermal efficiency increased by 1.31%with specific equivalent fuel consumption decreased by 22.54 g/kWh was obtained with SAPG system.The coal consumption was reduced by 4.75%when SAPG system operates in FS mode.
文摘A new synthetical knowledge representation model that integrates the attribute grammar model with the semantic network model was presented. The model mainly uses symbols of attribute grammar to establish a set of syntax and semantic rules suitable for a semantic network. Based on the model,the paper introduces a formal method defining data flow diagrams (DFD) and also simply explains how to use the method.
基金The Brazilian Sao Paulo State Research Foundation(FAPESP)partially supported this research(grants 2012/15824-6 and 2012/07243-3)
文摘Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimination diagrams fail to correctly classify them,i.e.many mafic
基金the research project ‘‘INDO HCM WP-7’’ sponsored by CSIR-CRRI
文摘Pedestrian flow parameters are analysed in this study considering linear and non-linear relationships between stream flow parameters using conventional and soft computing approach. Speed-density relationship serves as a fundamental relationship, Single-regime con- cepts and deterministic models like Greenshield and Underwood were applied in the study to describe bidirec- tional flow characteristics on sidewalks and carriageways around transport terminals in India. Artificial Neural Net- work (ANN) approach is also used for traffic flow mod- elling to build a relationship between different pedestrian flow parameters. A non-linear model based on ANN is suggested and compared with the other deterministic models. Out of the aforesaid models, ANN model demonstrated good results based on accuracy measure- ment. Also these ANN models have an advantage in terms of their self-processing and intelligent behaviour. Flow parameters are estimated by ANN model using MFD (Macroscopic Fundamental Diagram). Estimated mean absolute error (MAE) and root mean square error (RMSE)values for the best fitted ANN model are 3.83 and 4.73 m/ min, respectively, less than those for the other models for sidewalk movement. Further estimated MAE and RMSE values of ANN model for carriageway movement are 4.02 and 4.98 m/min, respectively, which are comparatively less than those of the other models. ANN model gives better performance in fitness of model and future prediction of flow parameters. Also when using linear regression model between observed and estimated values for speed and flow parameters, performance of ANN model gives better fitness to predict data as compared to deterministic model. R value for speed data prediction is 0.756 and for flow data pre- diction is 0.997 using ANN model at sidewalk movement around transport terminal.
文摘针对航天嵌入式软件(aerospace embedded software,AES)时序需求复杂带来的时序需求定义不准确问题,提出一种基于MARTE(modeling and analysis of real-time and embedded systems)模型的数据流时序(data flow timing based on MARTE,DFT-MARTE)模型,设计基于该模型的处理点缓存计算算法、时序偏离概率检测算法和时序序列分析算法。处理点缓存计算算法动态更新缓存空间,使后续时序检测正常执行;时序偏离概率检测算法利用多线程并发模拟时序特性,检测需求中时序偏离问题;时序序列分析算法是基于梯度下降算法,拟合时序序列,指导用户优化需求。该模型相比传统数据流模型更适用航天嵌入式软件,利于后续开发和维护,具有极高的应用价值。
文摘The Moody Diagram is widely used to determine the friction factor for fluid flow in pipes. The diagram combines the effects of Reynolds number and relative roughness to determine the friction factor. The relationship is highly non-linear and appears to have a complex interaction between viscous and boundary roughness effects. The Moody Diagram is based on predictions from an equation developed by Colebrook in 1939. The relationship requires an iteration process to make predictions. While empirical relationships have been developed that provide good predictions without an iteration process, no one has fully explained the cause for the observed results. The objective of this paper is to present a logical development for prediction of the friction factor. An equation has been developed that models the summed effect of both the laminar sublayer and the boundary roughness on the fluid profile and the resulting friction factor for pipes. The new equation does not require an iteration procedure to obtain values for the friction factor. Predicted results match well with values generated from Colebrook’s work that is expressed in the Moody Diagram. Predictions are within one percent of Colebrook values and generally less than 0.3 percent error from his values. The development provides insight to how processes operating at the boundary cause the friction factor to change.
文摘The shear-thinning/thickening effects on the plane Couette-Poiseuille flow with a uniform crossflow are studied. The detailed solution procedures for both theo- retical and numerical purposes are given. In order to clarify the difference between the Newtonian flow and the power-law flow, all cases of the plane Couette-Poiseuille flows with uniform crossflows for different power indexes are assigned to the phase diagram in the parameter plane corresponding to the Couette number and the crossflow Reynolds number. The effects of shear-thinning/thickening on the phase diagram are discussed. An important feature of the shear-thinning circumstance distinguished from the shear- thickening circumstance is discovered.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41130639, 51179045, 41201028)the Nonprofit Industry Financial Program of MWR of China (201501022)
文摘Intense human activities have greatly changed the flood generation conditions in most areas of the world, and have destroyed the consistency in the annual flood peak and volume series. For design flood estimation, coaxial correlation diagram and conceptual hydrological model are two frequently used tools to adjust and reconstruct the flood series under human disturbance. This study took a typical mountain catchment of the Haihe River Basin as an example to investigate the effects of human activities on flood regime and to compare and assess the two adjustment methods. The main purpose is to construct a conceptual hydrological model which can incorporate the effects of human activities. The results show that the coaxial correlation diagram is simple and widely-used, but can only adjust the time series of total flood volumes. Therefore, it is only applicable under certain conditions(e.g. There is a strong link between the flood peaks and volumes and the link is not significantly affected by human activities). The conceptual model is a powerful tool to adjust the time series of both flood peak flows and flood volumes over different durations provided that it is closely related to the catchment hydrological characteristics, specifically accounting for the effects of human activities, and incorporating expert knowledge when estimating or calibrating parameters. It is suggested that the two methods should be used together to cross check each other.
文摘The “Citizen-Centric Complaint Reporting and Analyzing Mechanism” project is designed to create an online complaint system, called “e-Complaint”, to allow citizens to file complaints related to crime and misconduct in a secure and user-friendly way. The proposed system aims to address the challenges of the current complaint system, ensuring transparency and accountability in the police force. The “e-Complaint” system aims to increase police accountability and transparency and has significant benefits for both citizens and police departments.