Automatic voltage regulators(AVR)are designed to manipulate a synchronous generator’s voltage level automatically.Proportional integral derivative(PID)controllers are typically used in AVR systems to regulate voltage...Automatic voltage regulators(AVR)are designed to manipulate a synchronous generator’s voltage level automatically.Proportional integral derivative(PID)controllers are typically used in AVR systems to regulate voltage.Although advanced PID tuning methods have been proposed,the actual voltage response differs from the theoretical predictions due to modeling errors and system uncertainties.This requires continuous fine tuning of the PID parameters.However,manual adjustment of these parameters can compromise the stability and robustness of the AVR system.This study focuses on the online self-tuning of PID controllers called indirect design approach-2(IDA-2)in AVR systems while preserving robustness.In particular,we indirectly tune the PID controller by shifting the frequency response.The new PID parameters depend on the frequency-shifting constant and the previously optimized PID parameters.Adjusting the frequency-shifting constant modifies all the PID parameters simultaneously,thereby improving the control performance and robustness.We evaluate the robustness of the proposed online PID tuning method by comparing the gain margins(GMs)and phase margins(PMs)with previously optimized PID parameters during parameter uncertainties.The proposed method is further evaluated in terms of disturbance rejection,measurement noise,and frequency response analysis during parameter uncertainty calculations against existing methods.Simulations show that the proposed method significantly improves the robustness of the controller in the AVR system.In summary,online self-tuning enables automated PID parameter adjustment in an AVR system,while maintaining stability and robustness.展开更多
Geothermal energy is considered a renewable,environmentally friendly,especially carbon-free,sustainable energy source that can solve the problem of climate change.In general,countries with geothermal energy resources ...Geothermal energy is considered a renewable,environmentally friendly,especially carbon-free,sustainable energy source that can solve the problem of climate change.In general,countries with geothermal energy resources are the ones going through the ring of fire.Therefore,not every country is lucky enough to own this resource.As a country with 117 active volcanoes and within the world’s ring of fire,it is a country whose geothermal resources are estimated to be about 40%of the world’s geothermal energy potential.However,the percentage used compared to the geothermal potential is too small.Therefore,this is the main energy source that Indonesia is aiming to exploit and use.However,the deployment and development of this energy source are still facing many obstacles due to many aspects from budget sources due to high capital costs,factory construction location,quality of resources,and conflicts of the local community.In this context,determining the optimal locations for geothermal energy sites(GES)is one of the most important and necessary issues.To strengthen the selection methods,this study applies a two-layer fuzzy multi-criteria decision-making method.Through the layers,the Ordinal Priority Approach(OPA)is proposed to weight the sub-criteria,the main criterion,and the sustainability factors.In layer 2,the Neutrosophic Fuzzy Axiomatic Design(NFAD)is applied to rank and evaluate potential locations for geothermal plant construction.Choosing the right geothermal energy site can bring low-cost efficiency,no greenhouse gas emissions,and quickly become the main energy source providing electricity for Indonesia.The final ranking shows Papua,Kawah Cibuni,and Moluccas as the three most suitable cities to build geothermal energy systems.Kawah Cibuni was identified as the most potential GES in Indonesia,with a score of 0.46.Papua is the second most promising GES with a score of 0.45.Next is the Moluccas,with a score of 0.39.However,the three least potential sites among the 15 studied sites are Lumut Balai,Moluccas and Patuha,with scores of 0.08,0.11 and 0.17,respectively.The conclusion of this study also classifies positions into groups to aid in decision-making.展开更多
In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed: (1) active control can provide significant...In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed: (1) active control can provide significantly superior supplemental damping to a building, but causes a small frequency shift; (2) the linear quadratic regulator (LQR)-based control force is composed of an elastic restoring force component and a damping force component, where the damping force is almost identical to the total control force, however, the elastic restoring force is very small; and (3) the active control forces prevent mction most of the time during the entire control process. These three characteristics imply that active control systems connected to adjacent levels of a building behave like passive damping devices with adjustable parameters, namely damping characteristics in an active control, which is the mechanism used by semi-active control devices to reach similar performance as active control systems. Two indices are defined to quantify the damping characteristics of control forces in active control systems. These two indices can also be used to quantify the capacity of semi-active control to achieve the perfonrlance of active control. Based on the above observations, two principles are founded for optimization of parameters of semi-active control devices and passive dampers. The first is that the maximum output force of a semi-active or passive device to be designed is identical to an active device, called "design principle". The other is the response equivalent principle, which states that the response of a building with semi-active or passive devices is the same as with active devices when the same maximum output force is applied. The design procedure for semi-active control devices and passive dampers is described in detail. Finally, numerical simulations of two benchmark problems is conducted to demonstrate the damping characteristics of active control and investigate the capacity of semi-active control to achieve the same performance as active control.展开更多
This paper presents an innovative Soft Design Science Methodology for improving information systems security using multi-layered security approach. The study applied Soft Design Science Methodology to address the prob...This paper presents an innovative Soft Design Science Methodology for improving information systems security using multi-layered security approach. The study applied Soft Design Science Methodology to address the problematic situation on how information systems security can be improved. In addition, Soft Design Science Methodology was compounded with mixed research methodology. This holistic approach helped for research methodology triangulation. The study assessed security requirements and developed a framework for improving information systems security. The study carried out maturity level assessment to determine security status quo in the education sector in Tanzania. The study identified security requirements gap (IT security controls, IT security measures) using ISO/IEC 21827: Systems Security Engineering-Capability Maturity Model (SSE-CMM) with a rating scale of 0 - 5. The results of this study show that maturity level across security domain is 0.44 out of 5. The finding shows that the implementation of IT security controls and security measures for ensuring security goals are lacking or conducted in ad-hoc. Thus, for improving the security of information systems, organisations should implement security controls and security measures in each security domain (multi-layer security). This research provides a framework for enhancing information systems security during capturing, processing, storage and transmission of information. This research has several practical contributions. Firstly, it contributes to the body of knowledge of information systems security by providing a set of security requirements for ensuring information systems security. Secondly, it contributes empirical evidence on how information systems security can be improved. Thirdly, it contributes on the applicability of Soft Design Science Methodology on addressing the problematic situation in information systems security. The research findings can be used by decision makers and lawmakers to improve existing cyber security laws, and enact laws for data privacy and sharing of open data.展开更多
This paper addresses a problem of observer-based sensor fault reconstruction for continuous-time systems subject to sensor faults and measurement disturbances via a descriptor system approach. An augmented descriptor ...This paper addresses a problem of observer-based sensor fault reconstruction for continuous-time systems subject to sensor faults and measurement disturbances via a descriptor system approach. An augmented descriptor plant is first formulated, by assembling measurement disturbances and sensor faults into an auxiliary state vector. Then a novel descriptor state observer for the augmented plant is constructed such that simultaneous reconstruction of original system states, sensor faults and measurement disturbances are obtained readily. Sufficient conditions for the existence of the proposed observer are explicitly provided, and the application scope of the observer is further discussed. In addition, an extension of the proposed linear approach to a class of nonlinear systems with Lipschitz constraints is investigated. Finally, two numerical examples are simulated to illustrate the effectiveness of the proposed fault-reconstructing approaches.展开更多
The serious competition environment of global marke t requests the enterprise to change traditional product development strategy and a dopt new theory in order to meet diverse customer needs while maintaining near m a...The serious competition environment of global marke t requests the enterprise to change traditional product development strategy and a dopt new theory in order to meet diverse customer needs while maintaining near m ass production efficiency, which is the main philosophy of mass customization. P roduct family design is research focus at present and also is the core technolog y of DFMC (design for mass customization). Firstly, this paper explores the fund amental issues of product family, such as concepts of modularity, commonality/di versity, product platform and product family architecture etc. We compare the te rminology between product family and object-oriented approach in the next step. Thirdly, this paper puts forwards one product family design methodology based o n product platform and under different phase of product life cycle constrains, f or example, functional, assembly and service etc. At the end section of this pap er, we applied, the object-oriented approach in above mentioned product family design methodology to realize the design process. In one word, this paper propos ed one product family design methodology based on object oriented approach and p roduct life cycle consideration, especially the conjointness of characteristic o f OOA and concepts of product family. The main property of OOA are encapsulation , inherence and polymorphism. Encapsulation can represent the module or building blocks of product family. Inherence can be extended to describe the modularity and commonality, and also be used to construct variant space. Alternative specif ic of product family architecture can be embodied with polymorphism. And fin aly, we give the future work contents. In order to derive the product platform a nd achieve modularity and commonality/diversity, interface management between bu ilding block is necessary. The question is how the OOA can be applied in interfa ce management to get our aim OOA is the basis of many information management sy stem, then the question is how to build one system to manage the information of product family and support mass customization The third question is how to deve lop one computer aided tool to facilitate the application of OOA for product fam ily design, even be used to category of design for mass customization.展开更多
We present a new aerodynamic design method based on the lattice Boltzmann method (LBM) and the adjoint approach. The flow field and the adjoint equation are numerically simulated by the GILBM (generalized form of i...We present a new aerodynamic design method based on the lattice Boltzmann method (LBM) and the adjoint approach. The flow field and the adjoint equation are numerically simulated by the GILBM (generalized form of interpolation supplemented LBM) on non-uniform meshes. The first-order approximation for the equilibrium dis- tribution function on the boundary is proposed to diminish the singularity of boundary conditions. Further, a new treatment of the solid boundary in the LBM is described par- ticularly for the airfoil optimization design problem. For a given objective function, the adjoint equation and its boundary conditions are derived analytically. The feasibility and accuracy of the new approach have been perfectly validated by the design optimization of NACA0012 airfoil.展开更多
The effect of formulation variables on in-vitro release and permeation properties of carvedilol from transdermal patch was studied by varying one factor at a time as preliminary study.Based on these results,design of ...The effect of formulation variables on in-vitro release and permeation properties of carvedilol from transdermal patch was studied by varying one factor at a time as preliminary study.Based on these results,design of experiments technique was applied followed by regression analysis and response surface methodology to optimize formulation variables.Central Composite IV model design was used with four formulation variables:drug loading,matrix thickness,adhesive layer thickness,and propylene glycol concentration.Nineteen formulations were prepared according to the design;and the effect of formulation variables was studied on in-vitro release and permeation profiles of these formulations.In all cases,the permeation profiles paralleled in-vitro release profiles.The drug released at 7 h and 24 h was used as release response parameters while permeation flux obtained was employed as permeation response parameter.All four formulation variables were found to be significant for release properties and three of these exhibited significant effect on permeation profile of carvedilol across artificial membrane.Constrained optimization,using 47.9%of cumulative carvedilol released at 7 h and 99.8%at 24 h as well as 25.7 mg/cm2/h of permeation flux,was applied to obtain desired release and permeation profiles.Experimentally,carvedilol was observed to release from the optimized formulation with 51.4%drug release at 7 h and 98.5%at 24 h with an observed flux value of 27.4 mg/cm2/h across artificial membrane,which showed an excellent agreement with the predicted values.The results of this investigation show that the quadratic mathematical model developed could be used to further predict formulations with desirable release and permeation properties.展开更多
This research provides an exploration of a biomimetic approach in the process of designing a candelabra model using linear shaped leaves of a Bell flower.The design process described in this research contains two step...This research provides an exploration of a biomimetic approach in the process of designing a candelabra model using linear shaped leaves of a Bell flower.The design process described in this research contains two steps:biological and geometrical.In the first biological step,a proper model for the creation of an urban element was found from nature in a Bell flower(Campanula persicifolia L.).The upper leaves of the selected plant,which are small with a linear spear and sharpening at the top,were chosen for the modeling process.The second step included applying two geometrical methods,i.e.,Voronoi diagrams and Delaunay triangulation.A geometrical leaf form of the selected plant species and the modeling process were obtained using aparametric modeling software,Blender.Using different Blender plug-ins and modifiers,Delaunay triangulation and Voronoi diagram were implemented by marking the starting points on the leaf form in the image data source,adjusting the Delaunay triangulation parameters,and creating Voronoi diagrams in which the Voronoi points were located at the shortest distance from the edges of the Voronoi polygon.Consequently,a three dimensional model of a candelabra was developed through this study.展开更多
In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal sys...In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal system based on that model to achieve hierarchical and modular development and verification methods. Anumber of refinement rules are used to decompose the specification into smaller ones and calculate program fromthe展开更多
The integral practical and aesthetic design teaching of architecture and site environment is expected to deal with the junior-grade design teaching in architecture major with a current situation that the insufficient ...The integral practical and aesthetic design teaching of architecture and site environment is expected to deal with the junior-grade design teaching in architecture major with a current situation that the insufficient consideration of the site environment and the chaotic city image, which caused by long-term emphasis on single function and personality performance of architecture. The key to the integral practicability and aesthetics is the emphasis on the integrality of spatial logical order of those two factors, which contains the integral harmony of function attributes, scale, logics, and modal relationships and so on. Combine with the teaching of kindergarten architecture design, using architecture and site logic model teaching methodology, through the extraction cognitive teaching approach of the site environment order logics, the cognitive teaching approach of kindergarten architecture spatial logics, the strategic teaching approach of the congruent design of the integral order of architecture and site environment logics, module and model congruent counterpoint design teaching approach of architecture and large site environment order logics, organization and construction integrated design teaching approach of architecture and small site environment spatial logics, and result design teaching approach of architectures integrated into the landscape of large site environment and their surrounding small site environment and other teaching procedures to complete die teaching tasks of the integral practical and aesthetic design of kindergarten architecture and site environment.展开更多
The criteria of sustainable design have been already received for reducing heating energy consumption (i.e. Passivhaus standard and first fulfillment of the EPDB Directive). Nowadays, many research are being involve...The criteria of sustainable design have been already received for reducing heating energy consumption (i.e. Passivhaus standard and first fulfillment of the EPDB Directive). Nowadays, many research are being involved to extend the passive standard to buildings in mild climate areas. Compared to building efficiency in the middle European area, the requirements for sustainable development of construction in the Mediterranean area imply an higher and more articulated passive control of outside/inside energy flows in order to extend energy efficiency measures to the whole year. This is based on an intense interaction between external climatic conditions and the building whole performance, with a dynamic behavior according to climate seasonal changes and inside comfort. Consequently, the integrated design of building fabrics, conceived not as separated components but as complex organism and system of interaction, increases its potential and strategic aim for reducing building consumptions of whole year in the mild climate. This paper demonstrates, both in new constructions and in the renovation of existing buildings, that the whole performance approach is the most suitable for sustainable design in a typical Mediterranean climate in order to increase the efficiency with controlled investments. The aim of this research is to show, through some case studies in Sardinia, that this sensitive and performance approach could optimize the ratio between economic costs and energy and environmental benefits. Only through an integrated and intelligent design of the architectural organism it is possible to achieve the new targets for sustainable building development, even for mild climate areas, required by European Directive 2002/91/EC.展开更多
In the current scenario of global competition and short product life cycles, customer-defined satisfaction has attracted interest in artifact design. Accordingly, intelligent decision-making through multi-objective op...In the current scenario of global competition and short product life cycles, customer-defined satisfaction has attracted interest in artifact design. Accordingly, intelligent decision-making through multi-objective optimization has been proposed as an efficient method for human-centered manufacturing. However, previous vast researches on optimization have been mainly focused on optimization theory and optimization techniques and paid little interests on the process of problem formulation itself. In this paper, therefore, the authors present a total framework for supporting multi-objective decision making. Then, the authors try to solve the formulated multi-objective optimization problem that involves both qualitative and quantitative performance measures as a general consequence from the above procedure. Taking especially quality as a qualitative measure, the authors gave a new idea to evaluate the quality quantitatively. Additionally, to facilitate the portability of the proposed method in multidisciplinary decision-making environments, the authors implement the proposal algorithm in an Excel spreadsheet and validate the effectiveness of the approach through a case study.展开更多
Reading competence is one of the basic skills of language acquisition.The teaching of reading skill has been attached great importance to in College English education in China.For decades,people have made efforts to i...Reading competence is one of the basic skills of language acquisition.The teaching of reading skill has been attached great importance to in College English education in China.For decades,people have made efforts to improve the classroom teaching effects through various means,one of which is that of communicative approach.This paper attempts to explore the design of reading comprehension exercise through a case study in the light of communicative theory,thus providing an alternative to the conventional reading course teaching method.展开更多
Speaking competence is one of the basic skills of language acquisition.The teaching of speaking skill has been attached great importance to in College English education in China.For decades,people have made efforts to...Speaking competence is one of the basic skills of language acquisition.The teaching of speaking skill has been attached great importance to in College English education in China.For decades,people have made efforts to improve the classroom teaching effects through various means,one of which is that of communicative approach.This paper attempts to explore the design of a spoken English lesson through a case study in the light of communicative theory,thus providing an alternative to the conventional spoken English course teaching method.展开更多
The robust design approach based on Taguchi's design of experiment (DOE) coupled with the traditional finite element analysis (FEA) is applied to the static design of a sedan door. This method aims at shortening ...The robust design approach based on Taguchi's design of experiment (DOE) coupled with the traditional finite element analysis (FEA) is applied to the static design of a sedan door. This method aims at shortening the design period, reducing the calculation cost and improving the competitive competence. First, the pe^ormance re- quirements, the control factors and the corresponding levels are determined to design a DOE table. Second, based on the schemes from the DOE table, sensitive control factors are distinguished from the results of the FEA method. Finally, the optimum design is chosen after comparisons and analyses of these performance response graphs. Performance results of the optimum design indicate that the application of the robust approach and FEA can greatly im- prove the quality of the door system, satisfy the requirements of products, underline the design purpose and shorten the design period.展开更多
The three main approaches in inquisitive research design are qualitative,quantitative,and mixed methods[1].However,recent developments in the research field have resulted in multiple other approaches,borrowing ideas f...The three main approaches in inquisitive research design are qualitative,quantitative,and mixed methods[1].However,recent developments in the research field have resulted in multiple other approaches,borrowing ideas from a broad range of fields.One such approach is the practice-led approach.This approach involves an efficient design process,novel qualitative interviewing methods,together with data mining procedures from quantitative data collection[2].This paper assesses the practice-led approach used in user experience(UX)design,together with three approaches:co-design,service design,and reflective practice.展开更多
Synthesis Studio is an architectural,planning,and design consultancy practice,led by Barbora Baloghova and Gilo Holtzman,who work independently,developing each one’s interests and expertise while collaborating on var...Synthesis Studio is an architectural,planning,and design consultancy practice,led by Barbora Baloghova and Gilo Holtzman,who work independently,developing each one’s interests and expertise while collaborating on various projects under the Synthesis Studio Brand.The studio’s mission is to excel in environmentally and socially sustainable building and planning practices,by research,design,and policy advocacy,and through collaboration with other professionals.In creating a community that works in harmony and reciprocity to its natural environment,we approach each site as an ecological system.Thus,the site layout and building design should perform in harmony with its surrounding environment and the needs of its future residents.For example,when planning and designing residential areas and buildings,we use research and implement the appropriate technologies in regard to waste management(grey water,composting,effluent)together with the form,location,orientation,shading,and social needs.Designing and planning places for people is a challenge.On the one hand,if prospective residents are not engaged in shaping their future residence,it means that places are created based on preconceived notions of how people ought to live,or how they should use a place or a space.On the other hand,working with many prospective residents means that an architect also needs to act as a facilitator,navigating through diverse thoughts and ideas and then translating them into physical form.The latter is achieved by prioritizing and understanding the importance of engaging with the community at various levels,from the group process of running meetings and decision-making to planning and design workshops.The overall aim is to demonstrate a range of planning and architectural solutions for progressive residential models both in rural and urban settings.The encouragement of a participatory process means that each participant/stakeholder becomes an important contributor to the planning and design process,and has some role in decision-making and is extremely important in achieving the best design for our immediate home and neighborhood environments.This process has been aptly named‘community by design and by the people’.展开更多
To solve the finite-time error-tracking problem in mis-sile guidance,this paper presents a unified design approach through error dynamics and free-time convergence theory.The proposed approach is initiated by establis...To solve the finite-time error-tracking problem in mis-sile guidance,this paper presents a unified design approach through error dynamics and free-time convergence theory.The proposed approach is initiated by establishing a desired model for free-time convergent error dynamics,characterized by its independence from initial conditions and guidance parameters,and adjustable convergence time.This foundation facilitates the derivation of specific guidance laws that integrate constraints such as leading angle,impact angle,and impact time.The theoretical framework of this study elucidates the nuances and synergies between the proposed guidance laws and existing methodologies.Empirical evaluations through simulation comparisons underscore the enhanced accuracy and adaptability of the proposed laws.展开更多
基金the Malaysian Ministry of Higher Education(MOHE)for their support through the Fundamental Research Grant Scheme(FRGS/1/2021/ICT02/UMP/03/3)(UMPSA Reference:RDU 210117)。
文摘Automatic voltage regulators(AVR)are designed to manipulate a synchronous generator’s voltage level automatically.Proportional integral derivative(PID)controllers are typically used in AVR systems to regulate voltage.Although advanced PID tuning methods have been proposed,the actual voltage response differs from the theoretical predictions due to modeling errors and system uncertainties.This requires continuous fine tuning of the PID parameters.However,manual adjustment of these parameters can compromise the stability and robustness of the AVR system.This study focuses on the online self-tuning of PID controllers called indirect design approach-2(IDA-2)in AVR systems while preserving robustness.In particular,we indirectly tune the PID controller by shifting the frequency response.The new PID parameters depend on the frequency-shifting constant and the previously optimized PID parameters.Adjusting the frequency-shifting constant modifies all the PID parameters simultaneously,thereby improving the control performance and robustness.We evaluate the robustness of the proposed online PID tuning method by comparing the gain margins(GMs)and phase margins(PMs)with previously optimized PID parameters during parameter uncertainties.The proposed method is further evaluated in terms of disturbance rejection,measurement noise,and frequency response analysis during parameter uncertainty calculations against existing methods.Simulations show that the proposed method significantly improves the robustness of the controller in the AVR system.In summary,online self-tuning enables automated PID parameter adjustment in an AVR system,while maintaining stability and robustness.
文摘Geothermal energy is considered a renewable,environmentally friendly,especially carbon-free,sustainable energy source that can solve the problem of climate change.In general,countries with geothermal energy resources are the ones going through the ring of fire.Therefore,not every country is lucky enough to own this resource.As a country with 117 active volcanoes and within the world’s ring of fire,it is a country whose geothermal resources are estimated to be about 40%of the world’s geothermal energy potential.However,the percentage used compared to the geothermal potential is too small.Therefore,this is the main energy source that Indonesia is aiming to exploit and use.However,the deployment and development of this energy source are still facing many obstacles due to many aspects from budget sources due to high capital costs,factory construction location,quality of resources,and conflicts of the local community.In this context,determining the optimal locations for geothermal energy sites(GES)is one of the most important and necessary issues.To strengthen the selection methods,this study applies a two-layer fuzzy multi-criteria decision-making method.Through the layers,the Ordinal Priority Approach(OPA)is proposed to weight the sub-criteria,the main criterion,and the sustainability factors.In layer 2,the Neutrosophic Fuzzy Axiomatic Design(NFAD)is applied to rank and evaluate potential locations for geothermal plant construction.Choosing the right geothermal energy site can bring low-cost efficiency,no greenhouse gas emissions,and quickly become the main energy source providing electricity for Indonesia.The final ranking shows Papua,Kawah Cibuni,and Moluccas as the three most suitable cities to build geothermal energy systems.Kawah Cibuni was identified as the most potential GES in Indonesia,with a score of 0.46.Papua is the second most promising GES with a score of 0.45.Next is the Moluccas,with a score of 0.39.However,the three least potential sites among the 15 studied sites are Lumut Balai,Moluccas and Patuha,with scores of 0.08,0.11 and 0.17,respectively.The conclusion of this study also classifies positions into groups to aid in decision-making.
基金National Fundamental Research Program (973) Under Grant No. 2007CB714204the R & D Program Under Grant No. 2006BAJ03B06NSFC Under Grant No. 90815027
文摘In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed: (1) active control can provide significantly superior supplemental damping to a building, but causes a small frequency shift; (2) the linear quadratic regulator (LQR)-based control force is composed of an elastic restoring force component and a damping force component, where the damping force is almost identical to the total control force, however, the elastic restoring force is very small; and (3) the active control forces prevent mction most of the time during the entire control process. These three characteristics imply that active control systems connected to adjacent levels of a building behave like passive damping devices with adjustable parameters, namely damping characteristics in an active control, which is the mechanism used by semi-active control devices to reach similar performance as active control systems. Two indices are defined to quantify the damping characteristics of control forces in active control systems. These two indices can also be used to quantify the capacity of semi-active control to achieve the perfonrlance of active control. Based on the above observations, two principles are founded for optimization of parameters of semi-active control devices and passive dampers. The first is that the maximum output force of a semi-active or passive device to be designed is identical to an active device, called "design principle". The other is the response equivalent principle, which states that the response of a building with semi-active or passive devices is the same as with active devices when the same maximum output force is applied. The design procedure for semi-active control devices and passive dampers is described in detail. Finally, numerical simulations of two benchmark problems is conducted to demonstrate the damping characteristics of active control and investigate the capacity of semi-active control to achieve the same performance as active control.
文摘This paper presents an innovative Soft Design Science Methodology for improving information systems security using multi-layered security approach. The study applied Soft Design Science Methodology to address the problematic situation on how information systems security can be improved. In addition, Soft Design Science Methodology was compounded with mixed research methodology. This holistic approach helped for research methodology triangulation. The study assessed security requirements and developed a framework for improving information systems security. The study carried out maturity level assessment to determine security status quo in the education sector in Tanzania. The study identified security requirements gap (IT security controls, IT security measures) using ISO/IEC 21827: Systems Security Engineering-Capability Maturity Model (SSE-CMM) with a rating scale of 0 - 5. The results of this study show that maturity level across security domain is 0.44 out of 5. The finding shows that the implementation of IT security controls and security measures for ensuring security goals are lacking or conducted in ad-hoc. Thus, for improving the security of information systems, organisations should implement security controls and security measures in each security domain (multi-layer security). This research provides a framework for enhancing information systems security during capturing, processing, storage and transmission of information. This research has several practical contributions. Firstly, it contributes to the body of knowledge of information systems security by providing a set of security requirements for ensuring information systems security. Secondly, it contributes empirical evidence on how information systems security can be improved. Thirdly, it contributes on the applicability of Soft Design Science Methodology on addressing the problematic situation in information systems security. The research findings can be used by decision makers and lawmakers to improve existing cyber security laws, and enact laws for data privacy and sharing of open data.
基金supported by the National Natural Science Foundation of China(61104026)the Open Funding for National Defense Key Subject Laboratory of Micro and Small Spacecraft Technology(20090450126)
文摘This paper addresses a problem of observer-based sensor fault reconstruction for continuous-time systems subject to sensor faults and measurement disturbances via a descriptor system approach. An augmented descriptor plant is first formulated, by assembling measurement disturbances and sensor faults into an auxiliary state vector. Then a novel descriptor state observer for the augmented plant is constructed such that simultaneous reconstruction of original system states, sensor faults and measurement disturbances are obtained readily. Sufficient conditions for the existence of the proposed observer are explicitly provided, and the application scope of the observer is further discussed. In addition, an extension of the proposed linear approach to a class of nonlinear systems with Lipschitz constraints is investigated. Finally, two numerical examples are simulated to illustrate the effectiveness of the proposed fault-reconstructing approaches.
文摘The serious competition environment of global marke t requests the enterprise to change traditional product development strategy and a dopt new theory in order to meet diverse customer needs while maintaining near m ass production efficiency, which is the main philosophy of mass customization. P roduct family design is research focus at present and also is the core technolog y of DFMC (design for mass customization). Firstly, this paper explores the fund amental issues of product family, such as concepts of modularity, commonality/di versity, product platform and product family architecture etc. We compare the te rminology between product family and object-oriented approach in the next step. Thirdly, this paper puts forwards one product family design methodology based o n product platform and under different phase of product life cycle constrains, f or example, functional, assembly and service etc. At the end section of this pap er, we applied, the object-oriented approach in above mentioned product family design methodology to realize the design process. In one word, this paper propos ed one product family design methodology based on object oriented approach and p roduct life cycle consideration, especially the conjointness of characteristic o f OOA and concepts of product family. The main property of OOA are encapsulation , inherence and polymorphism. Encapsulation can represent the module or building blocks of product family. Inherence can be extended to describe the modularity and commonality, and also be used to construct variant space. Alternative specif ic of product family architecture can be embodied with polymorphism. And fin aly, we give the future work contents. In order to derive the product platform a nd achieve modularity and commonality/diversity, interface management between bu ilding block is necessary. The question is how the OOA can be applied in interfa ce management to get our aim OOA is the basis of many information management sy stem, then the question is how to build one system to manage the information of product family and support mass customization The third question is how to deve lop one computer aided tool to facilitate the application of OOA for product fam ily design, even be used to category of design for mass customization.
基金Project supported by the National Basic Research Program of China(No.2014CB744100)the National Natural Science Foundation of China(Nos.61403245 and 91648119)the Shanghai Municipal Science and Technology Commision(No.14500500400)
文摘We present a new aerodynamic design method based on the lattice Boltzmann method (LBM) and the adjoint approach. The flow field and the adjoint equation are numerically simulated by the GILBM (generalized form of interpolation supplemented LBM) on non-uniform meshes. The first-order approximation for the equilibrium dis- tribution function on the boundary is proposed to diminish the singularity of boundary conditions. Further, a new treatment of the solid boundary in the LBM is described par- ticularly for the airfoil optimization design problem. For a given objective function, the adjoint equation and its boundary conditions are derived analytically. The feasibility and accuracy of the new approach have been perfectly validated by the design optimization of NACA0012 airfoil.
基金The authors acknowledge financial assistance and research facilities provided by College of Pharmacy and Health Sciences,St.John’s University to carry out this research。
文摘The effect of formulation variables on in-vitro release and permeation properties of carvedilol from transdermal patch was studied by varying one factor at a time as preliminary study.Based on these results,design of experiments technique was applied followed by regression analysis and response surface methodology to optimize formulation variables.Central Composite IV model design was used with four formulation variables:drug loading,matrix thickness,adhesive layer thickness,and propylene glycol concentration.Nineteen formulations were prepared according to the design;and the effect of formulation variables was studied on in-vitro release and permeation profiles of these formulations.In all cases,the permeation profiles paralleled in-vitro release profiles.The drug released at 7 h and 24 h was used as release response parameters while permeation flux obtained was employed as permeation response parameter.All four formulation variables were found to be significant for release properties and three of these exhibited significant effect on permeation profile of carvedilol across artificial membrane.Constrained optimization,using 47.9%of cumulative carvedilol released at 7 h and 99.8%at 24 h as well as 25.7 mg/cm2/h of permeation flux,was applied to obtain desired release and permeation profiles.Experimentally,carvedilol was observed to release from the optimized formulation with 51.4%drug release at 7 h and 98.5%at 24 h with an observed flux value of 27.4 mg/cm2/h across artificial membrane,which showed an excellent agreement with the predicted values.The results of this investigation show that the quadratic mathematical model developed could be used to further predict formulations with desirable release and permeation properties.
基金The Ministry of Education,Science and Technological Development of the Republic of Serbia,No.TP 36008(451–02-68/2020/14/2000169).
文摘This research provides an exploration of a biomimetic approach in the process of designing a candelabra model using linear shaped leaves of a Bell flower.The design process described in this research contains two steps:biological and geometrical.In the first biological step,a proper model for the creation of an urban element was found from nature in a Bell flower(Campanula persicifolia L.).The upper leaves of the selected plant,which are small with a linear spear and sharpening at the top,were chosen for the modeling process.The second step included applying two geometrical methods,i.e.,Voronoi diagrams and Delaunay triangulation.A geometrical leaf form of the selected plant species and the modeling process were obtained using aparametric modeling software,Blender.Using different Blender plug-ins and modifiers,Delaunay triangulation and Voronoi diagram were implemented by marking the starting points on the leaf form in the image data source,adjusting the Delaunay triangulation parameters,and creating Voronoi diagrams in which the Voronoi points were located at the shortest distance from the edges of the Voronoi polygon.Consequently,a three dimensional model of a candelabra was developed through this study.
基金ESPRIT Basic Research ProCoS project 3104 and 7071
文摘In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal system based on that model to achieve hierarchical and modular development and verification methods. Anumber of refinement rules are used to decompose the specification into smaller ones and calculate program fromthe
文摘The integral practical and aesthetic design teaching of architecture and site environment is expected to deal with the junior-grade design teaching in architecture major with a current situation that the insufficient consideration of the site environment and the chaotic city image, which caused by long-term emphasis on single function and personality performance of architecture. The key to the integral practicability and aesthetics is the emphasis on the integrality of spatial logical order of those two factors, which contains the integral harmony of function attributes, scale, logics, and modal relationships and so on. Combine with the teaching of kindergarten architecture design, using architecture and site logic model teaching methodology, through the extraction cognitive teaching approach of the site environment order logics, the cognitive teaching approach of kindergarten architecture spatial logics, the strategic teaching approach of the congruent design of the integral order of architecture and site environment logics, module and model congruent counterpoint design teaching approach of architecture and large site environment order logics, organization and construction integrated design teaching approach of architecture and small site environment spatial logics, and result design teaching approach of architectures integrated into the landscape of large site environment and their surrounding small site environment and other teaching procedures to complete die teaching tasks of the integral practical and aesthetic design of kindergarten architecture and site environment.
文摘The criteria of sustainable design have been already received for reducing heating energy consumption (i.e. Passivhaus standard and first fulfillment of the EPDB Directive). Nowadays, many research are being involved to extend the passive standard to buildings in mild climate areas. Compared to building efficiency in the middle European area, the requirements for sustainable development of construction in the Mediterranean area imply an higher and more articulated passive control of outside/inside energy flows in order to extend energy efficiency measures to the whole year. This is based on an intense interaction between external climatic conditions and the building whole performance, with a dynamic behavior according to climate seasonal changes and inside comfort. Consequently, the integrated design of building fabrics, conceived not as separated components but as complex organism and system of interaction, increases its potential and strategic aim for reducing building consumptions of whole year in the mild climate. This paper demonstrates, both in new constructions and in the renovation of existing buildings, that the whole performance approach is the most suitable for sustainable design in a typical Mediterranean climate in order to increase the efficiency with controlled investments. The aim of this research is to show, through some case studies in Sardinia, that this sensitive and performance approach could optimize the ratio between economic costs and energy and environmental benefits. Only through an integrated and intelligent design of the architectural organism it is possible to achieve the new targets for sustainable building development, even for mild climate areas, required by European Directive 2002/91/EC.
文摘In the current scenario of global competition and short product life cycles, customer-defined satisfaction has attracted interest in artifact design. Accordingly, intelligent decision-making through multi-objective optimization has been proposed as an efficient method for human-centered manufacturing. However, previous vast researches on optimization have been mainly focused on optimization theory and optimization techniques and paid little interests on the process of problem formulation itself. In this paper, therefore, the authors present a total framework for supporting multi-objective decision making. Then, the authors try to solve the formulated multi-objective optimization problem that involves both qualitative and quantitative performance measures as a general consequence from the above procedure. Taking especially quality as a qualitative measure, the authors gave a new idea to evaluate the quality quantitatively. Additionally, to facilitate the portability of the proposed method in multidisciplinary decision-making environments, the authors implement the proposal algorithm in an Excel spreadsheet and validate the effectiveness of the approach through a case study.
文摘Reading competence is one of the basic skills of language acquisition.The teaching of reading skill has been attached great importance to in College English education in China.For decades,people have made efforts to improve the classroom teaching effects through various means,one of which is that of communicative approach.This paper attempts to explore the design of reading comprehension exercise through a case study in the light of communicative theory,thus providing an alternative to the conventional reading course teaching method.
文摘Speaking competence is one of the basic skills of language acquisition.The teaching of speaking skill has been attached great importance to in College English education in China.For decades,people have made efforts to improve the classroom teaching effects through various means,one of which is that of communicative approach.This paper attempts to explore the design of a spoken English lesson through a case study in the light of communicative theory,thus providing an alternative to the conventional spoken English course teaching method.
文摘The robust design approach based on Taguchi's design of experiment (DOE) coupled with the traditional finite element analysis (FEA) is applied to the static design of a sedan door. This method aims at shortening the design period, reducing the calculation cost and improving the competitive competence. First, the pe^ormance re- quirements, the control factors and the corresponding levels are determined to design a DOE table. Second, based on the schemes from the DOE table, sensitive control factors are distinguished from the results of the FEA method. Finally, the optimum design is chosen after comparisons and analyses of these performance response graphs. Performance results of the optimum design indicate that the application of the robust approach and FEA can greatly im- prove the quality of the door system, satisfy the requirements of products, underline the design purpose and shorten the design period.
文摘The three main approaches in inquisitive research design are qualitative,quantitative,and mixed methods[1].However,recent developments in the research field have resulted in multiple other approaches,borrowing ideas from a broad range of fields.One such approach is the practice-led approach.This approach involves an efficient design process,novel qualitative interviewing methods,together with data mining procedures from quantitative data collection[2].This paper assesses the practice-led approach used in user experience(UX)design,together with three approaches:co-design,service design,and reflective practice.
文摘Synthesis Studio is an architectural,planning,and design consultancy practice,led by Barbora Baloghova and Gilo Holtzman,who work independently,developing each one’s interests and expertise while collaborating on various projects under the Synthesis Studio Brand.The studio’s mission is to excel in environmentally and socially sustainable building and planning practices,by research,design,and policy advocacy,and through collaboration with other professionals.In creating a community that works in harmony and reciprocity to its natural environment,we approach each site as an ecological system.Thus,the site layout and building design should perform in harmony with its surrounding environment and the needs of its future residents.For example,when planning and designing residential areas and buildings,we use research and implement the appropriate technologies in regard to waste management(grey water,composting,effluent)together with the form,location,orientation,shading,and social needs.Designing and planning places for people is a challenge.On the one hand,if prospective residents are not engaged in shaping their future residence,it means that places are created based on preconceived notions of how people ought to live,or how they should use a place or a space.On the other hand,working with many prospective residents means that an architect also needs to act as a facilitator,navigating through diverse thoughts and ideas and then translating them into physical form.The latter is achieved by prioritizing and understanding the importance of engaging with the community at various levels,from the group process of running meetings and decision-making to planning and design workshops.The overall aim is to demonstrate a range of planning and architectural solutions for progressive residential models both in rural and urban settings.The encouragement of a participatory process means that each participant/stakeholder becomes an important contributor to the planning and design process,and has some role in decision-making and is extremely important in achieving the best design for our immediate home and neighborhood environments.This process has been aptly named‘community by design and by the people’.
基金supported by the National Natural Science Foundation of China(12002370).
文摘To solve the finite-time error-tracking problem in mis-sile guidance,this paper presents a unified design approach through error dynamics and free-time convergence theory.The proposed approach is initiated by establishing a desired model for free-time convergent error dynamics,characterized by its independence from initial conditions and guidance parameters,and adjustable convergence time.This foundation facilitates the derivation of specific guidance laws that integrate constraints such as leading angle,impact angle,and impact time.The theoretical framework of this study elucidates the nuances and synergies between the proposed guidance laws and existing methodologies.Empirical evaluations through simulation comparisons underscore the enhanced accuracy and adaptability of the proposed laws.