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 study examines the application of the Understanding by Design(UbD)approach to enhance students’cognitive,affective,and psychomotor learning domains,as well as their intercultural communication competence,in the ...This study examines the application of the Understanding by Design(UbD)approach to enhance students’cognitive,affective,and psychomotor learning domains,as well as their intercultural communication competence,in the Introduction to Chinese Culture course.UbD,a curriculum design framework emphasizing deep understanding over rote memorization,employs a“backward design”process to help students achieve a profound comprehension of Chinese culture and its modern implications.Through this approach,students also develop critical intercultural communication skills.The study offers helpful strategies for integrating English language teaching with Chinese cultural education,providing practical insights for curriculum development that bridges linguistic and cultural learning.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
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
China is increasingly attaching importance to coordination and scientific development between humanist and economic constructions, especially for protection on rural pastoral cultural landscape. For eco-village theory...China is increasingly attaching importance to coordination and scientific development between humanist and economic constructions, especially for protection on rural pastoral cultural landscape. For eco-village theory, planning and construction of pastoral culture landscape is just a breakthrough. The research used modern landscaping technology and analyzed pastoral landscape culture, facilitating transformation of agricultural production pattern and ushering in a new trend in terms of retaining rural cultural landscapes with Chinese characteristics and inheriting and innovating rural culture.展开更多
A direct digital design method （DDDM） of worm-gear drive is proposed. It is directly based on the simulation of manufacturing process and completely different from the conventional modeling method. The loaded tooth ...A direct digital design method （DDDM） of worm-gear drive is proposed. It is directly based on the simulation of manufacturing process and completely different from the conventional modeling method. The loaded tooth contact analysis （LTCA） method is analyzed, in which the advanced surface to surface searching technique is included. The influence of misalignment errors and contact deformations on contact zone and transmission error （TE） is discussed. Combined modification approach on worm tooth surface is presented. By means of DDDM and LTCA, it is very conven- ient to verify the effect of worm-gear drive＇s modification approach. The analysis results show that, the modification in profile direction reduces the sensitivity of worm-gear drive to misalignment errors and the modification in longitudinal direction decreases the TE. Thus the optimization design of worm-gear drive can be achieved prior to the actual manufacturing process.展开更多
It is important to improve residential thermal comfort in the high dense cities,in which wind environment is crucial.Waterside buildings take an advantage of micro-hydrological-climate in summer that should be used to...It is important to improve residential thermal comfort in the high dense cities,in which wind environment is crucial.Waterside buildings take an advantage of micro-hydrological-climate in summer that should be used to enhance residential thermal comfort especially in the subtropical region.In order to propose design approaches according to the outdoor thermal comfort of the waterside residential,a case study of Shenzhen She Kou residential district has been made.It focused on various factors that could have influence on wind environment for improving thermal comfort.Using wind velocity ratio(ΔRi)criterion,factors of building development volume,building direction and layout pattern,open space arrangement etc.have been broadly explored using FLUENT simulation.To planning parameters,the Floor Area Ratio(FAR)is significantly influence wind environment,the smaller FAR is better.To the vertical layout of the buildings,multi-storey layout and multi-storey&sub high-rise mixed layout would provide better wind environment.To the horizontal layout,the determinant is better than the peripheral.Other factors such as the buildings’direction towards the road,buildings’height,and open space setting,have influence on wind environment yet.In general,the more benefit of design layout for wind breezing,the better wind environment it could get.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
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
Design of experiment （DOE） was applied to determining the most important factors which influence ultimate tensile strength （UTS） of AA6061/SiC nanocomposites produced by friction stir processing （FSP）. Effect of...Design of experiment （DOE） was applied to determining the most important factors which influence ultimate tensile strength （UTS） of AA6061/SiC nanocomposites produced by friction stir processing （FSP）. Effect of four factors, including rotational speed, transverse speed, tool penetration depth and pin profile, on UTS, was investigated. By Taguchi method, the optimum of process parameters were determined. Analysis of variance shows that the rotational speed is the most influential parameter. The statistical results depict that UTS for threaded pin is larger than that for square pin. Also, the higher the rotational speed and the lower the transverse speed, the higher the UTS.展开更多
Conventional reinforced concrete piers are vulnerable to severe compressive damage under strong earthquake conditions and are difficult to quickly rehabilitate.This paper develops a new type of composite pier,consisti...Conventional reinforced concrete piers are vulnerable to severe compressive damage under strong earthquake conditions and are difficult to quickly rehabilitate.This paper develops a new type of composite pier,consisting of ultra-high-performance concrete(UHPC)and reinforced concrete(RC).This UHPC-RC composite pier uses a UHPC cover outside of an RC core to achieve a high load-carrying capacity and mitigate compressive damage.An experiment is performed to evaluate the performance of the UHPC-RC composite pier under cyclic deformation.The crack development,ultimate failure modes,and load-carrying capacities of the pier are observed.Because of the extraordinary compressive strength of UHPC,the composite pier suffers little compressive damage under large lateral deformations.The composite pier fails as a result of fracturing of the reinforcement.A numerical model is developed to reproduce the cyclic behavior of the composite pier.On the basis of the verified numerical model,a parametric analysis is used to investigate the influence of the thickness of the UHPC cover and the axial load ratio.Finally,an approach is recommended for designing composite piers.展开更多
In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically revi...In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically reviewed.In this context,general-ized odd-even mode theory is advanced to quantitatively and approximately describe the mutual coupling effect between a feed line and an antenna.As is mathematically deduced and demonstrated,the modal parity mismatch between the feed line and the antenna should ultimately dominate the unbalance phenomenon in antenna systems.Thus,an elegant,closed-form formula is derived to ap-proximately calculate the“unbalance degree”of a straight dipole off-center fed by a symmetric twin-wire line.Design approaches for the simplest,linear,1-D multimode resonant antennas are introduced.Moreover,the“falling tone excitation”law gauged based on prototype dipoles is revealed and used to develop a mode synthesis design approach for microstrip patch antennas(MPAs)and 2-D sectorial electric dipole antennas.Design examples with distinctive radiation performance are presented and discussed.Finally,possible development trends of multimode resonant antennas are prospected.展开更多
Organizational corporate social responsibility is a good practice by organizations. Organizations engagement in corporate social responsibility programs may benefit the organization and stakeholders. The focus of this...Organizational corporate social responsibility is a good practice by organizations. Organizations engagement in corporate social responsibility programs may benefit the organization and stakeholders. The focus of this paper is to explore the extent of employees＇ engagement in the organization＇s corporate responsibility programs by utilizing Unerman＇s （2007） stakeholders engagement framework. The main research question is how employees engage themselves in corporate social responsibility programs. This study employs a case study research design approach. The findings have shown that there is empowerment between employees and the management in the corporate social responsibility programs. Their involvement appears from their feedbacks and views in the surveys as well as discussion with regards to corporate responsibility programs. All in all, employees＇ engagement is seen as an important practice in the organization, particularly in planning, implementing, monitoring, and reporting the corporate responsibility program.展开更多
In 1999, the first International Maritime Confere- nce on Design for Safety was successfully held in Glasgow, UK as a WEGEMT Euro Conference with the sponsorship of the European Commission. Respo- nding to the expecta...In 1999, the first International Maritime Confere- nce on Design for Safety was successfully held in Glasgow, UK as a WEGEMT Euro Conference with the sponsorship of the European Commission. Respo- nding to the expectation from the world maritime safety community, the second was held in 2004 in Japan. The third and fourth were held in USA, 2007 and Italy, 2010, respectively. This year the Design for Safety conference including a single event of the 4th Workshop on Risk-Based Approaches in the Marine Industries will be held in Shanghai on November 25- 27, 2013. The conference is organized by Shanghai Jiao Tong University and is co-organized/sponsored by Marine Design and Research Institute of China （MARIC） and China Classification Society （CCS~.展开更多
The squirrel-cage elastic support is one of the most important components of an aero-engine rotor system.A proper structural design will favor the static and dynamic performances of the system.In view of the deficienc...The squirrel-cage elastic support is one of the most important components of an aero-engine rotor system.A proper structural design will favor the static and dynamic performances of the system.In view of the deficiency of the current shape optimization techniques,a new mapping approach is proposed to define shape design variables based on the parametric equations of 3D curves and surfaces.It is then applied for the slot shape optimization of a squirrel-cage elastic support.To this end,an automatic design procedure that integrates the Genetic Algorithm (GA) is developed to solve the problem.Two typical examples with different shape constraints are considered.Numerical results provide reasonable optimum designs for the improvement of stiffness and strength of the squirrel-cage elastic support.展开更多
A design-of-experiments methodology is used to develop a statistical model for the prediction of the hydrodynamics of a liquid–solid circulating fluidized bed. To illustrate the multilevel factorial design approach, ...A design-of-experiments methodology is used to develop a statistical model for the prediction of the hydrodynamics of a liquid–solid circulating fluidized bed. To illustrate the multilevel factorial design approach, a step by step methodology is taken to study the effects of the interactions among the independent factors considered on the performance variables. A multilevel full factorial design with three levels of the two factors and five levels of the third factor has been studied. Various statistical models such as the linear, two-factor interaction, quadratic, and cubic models are tested. The model has been developed to predict responses, viz., average solids holdup and solids circulation rate. The validity of the developed regression model is verified using the analysis of variance. Furthermore, the model developed was compared with an experimental dataset to assess its adequacy and reliability. This detailed statistical design methodology for non-linear systems considered here provides a very important tool for design and optimization in a cost-effective approach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
Technology and design are increasingly recognized as important drivers of social innovation(SI).While new-age technologies can disrupt the realm of social innovation through resource-efficient solutions and multiple o...Technology and design are increasingly recognized as important drivers of social innovation(SI).While new-age technologies can disrupt the realm of social innovation through resource-efficient solutions and multiple outcome benefits,the appliction of design thinking approaches and techniques can enhance the potential for SI through humancentered participatory processes and a socially shared vision and impact.Despite extensive research focusing on SI practices driven by technology and design respectively,few studies have concentrated on the synergistic effects of technology and design in the field of SI.This paper addresses this gap through an exploratory study on the incorporation and role of technology in the practice of design for SI.By applying the mapping approach to a sample of 81 Design-enabled Innovation(DEI)pilot projects in the DESIGNSCAPES project,the distribution,hosts and manifestations of technology footprints are identified,taking into account the multi-phase innovation processes and multifaceted role of design.Our findings suggest that in design-supported SI,technology can be integrated in a systematic and conventional manner across a range of domains related to people,interactions,contexts,and artefacts and that its interaction with design actions is highly dependent on the different roles of design,followed by a further discussion of a conceptual argument regarding the possible role of technology in supporting design for SI.Based on these findings and results,the article concludes with the limitations of the study and possible theoretical and managerial implications.展开更多
Parity–time(PT) symmetry has been demonstrated in the frame of classic optics. Its applications in laser science have resulted in unconventional control and manipulation of resonant modes. PT-symmetric periodic circu...Parity–time(PT) symmetry has been demonstrated in the frame of classic optics. Its applications in laser science have resulted in unconventional control and manipulation of resonant modes. PT-symmetric periodic circular Bragg lasers were previously proposed. Analyses with a transfer-matrix method have shown their superior properties of reduced threshold and enhanced modal discrimination between the radial modes. However, the properties of the azimuthal modes were not analyzed, which restricts further development of circular Bragg lasers. Here, we adopt the coupled-mode theory to design and analyze chirped circular Bragg lasers with radial PT symmetry. The new structures possess more versatile modal control with further enhanced modal discrimination between the azimuthal modes. We also analyze azimuthally modulated circular Bragg lasers with radial PT symmetry, which are shown to achieve even higher modal discrimination.展开更多
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.
基金The 2022 Guangdong Provincial Higher Education Teaching Quality and Reform Project“Research and Practice of English Teaching Integrating Ideological and Political Education into the Introduction to Chinese Culture Course Based on UbD Theory”。
文摘This study examines the application of the Understanding by Design(UbD)approach to enhance students’cognitive,affective,and psychomotor learning domains,as well as their intercultural communication competence,in the Introduction to Chinese Culture course.UbD,a curriculum design framework emphasizing deep understanding over rote memorization,employs a“backward design”process to help students achieve a profound comprehension of Chinese culture and its modern implications.Through this approach,students also develop critical intercultural communication skills.The study offers helpful strategies for integrating English language teaching with Chinese cultural education,providing practical insights for curriculum development that bridges linguistic and cultural learning.
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.
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China is increasingly attaching importance to coordination and scientific development between humanist and economic constructions, especially for protection on rural pastoral cultural landscape. For eco-village theory, planning and construction of pastoral culture landscape is just a breakthrough. The research used modern landscaping technology and analyzed pastoral landscape culture, facilitating transformation of agricultural production pattern and ushering in a new trend in terms of retaining rural cultural landscapes with Chinese characteristics and inheriting and innovating rural culture.
基金This project is supported by National Natural Science Foundation of China (No.E50575234).
文摘A direct digital design method （DDDM） of worm-gear drive is proposed. It is directly based on the simulation of manufacturing process and completely different from the conventional modeling method. The loaded tooth contact analysis （LTCA） method is analyzed, in which the advanced surface to surface searching technique is included. The influence of misalignment errors and contact deformations on contact zone and transmission error （TE） is discussed. Combined modification approach on worm tooth surface is presented. By means of DDDM and LTCA, it is very conven- ient to verify the effect of worm-gear drive＇s modification approach. The analysis results show that, the modification in profile direction reduces the sensitivity of worm-gear drive to misalignment errors and the modification in longitudinal direction decreases the TE. Thus the optimization design of worm-gear drive can be achieved prior to the actual manufacturing process.
文摘It is important to improve residential thermal comfort in the high dense cities,in which wind environment is crucial.Waterside buildings take an advantage of micro-hydrological-climate in summer that should be used to enhance residential thermal comfort especially in the subtropical region.In order to propose design approaches according to the outdoor thermal comfort of the waterside residential,a case study of Shenzhen She Kou residential district has been made.It focused on various factors that could have influence on wind environment for improving thermal comfort.Using wind velocity ratio(ΔRi)criterion,factors of building development volume,building direction and layout pattern,open space arrangement etc.have been broadly explored using FLUENT simulation.To planning parameters,the Floor Area Ratio(FAR)is significantly influence wind environment,the smaller FAR is better.To the vertical layout of the buildings,multi-storey layout and multi-storey&sub high-rise mixed layout would provide better wind environment.To the horizontal layout,the determinant is better than the peripheral.Other factors such as the buildings’direction towards the road,buildings’height,and open space setting,have influence on wind environment yet.In general,the more benefit of design layout for wind breezing,the better wind environment it could get.
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Design of experiment （DOE） was applied to determining the most important factors which influence ultimate tensile strength （UTS） of AA6061/SiC nanocomposites produced by friction stir processing （FSP）. Effect of four factors, including rotational speed, transverse speed, tool penetration depth and pin profile, on UTS, was investigated. By Taguchi method, the optimum of process parameters were determined. Analysis of variance shows that the rotational speed is the most influential parameter. The statistical results depict that UTS for threaded pin is larger than that for square pin. Also, the higher the rotational speed and the lower the transverse speed, the higher the UTS.
基金National Natural Science Foundation of China under Grant Nos.U21A20154 and 52078436the Sichuan Science and Technology Program under Grant Nos.2022JDRC0012,2023YFG0064 and 2023YFS0429the Opening Funding Project of the Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of the China Earthquake Administration。
文摘Conventional reinforced concrete piers are vulnerable to severe compressive damage under strong earthquake conditions and are difficult to quickly rehabilitate.This paper develops a new type of composite pier,consisting of ultra-high-performance concrete(UHPC)and reinforced concrete(RC).This UHPC-RC composite pier uses a UHPC cover outside of an RC core to achieve a high load-carrying capacity and mitigate compressive damage.An experiment is performed to evaluate the performance of the UHPC-RC composite pier under cyclic deformation.The crack development,ultimate failure modes,and load-carrying capacities of the pier are observed.Because of the extraordinary compressive strength of UHPC,the composite pier suffers little compressive damage under large lateral deformations.The composite pier fails as a result of fracturing of the reinforcement.A numerical model is developed to reproduce the cyclic behavior of the composite pier.On the basis of the verified numerical model,a parametric analysis is used to investigate the influence of the thickness of the UHPC cover and the axial load ratio.Finally,an approach is recommended for designing composite piers.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFE0205900)the Key Technologies R&D Program of Jiangsu(Prospective and Key Technologies for Industry)(Grant Nos.BE2022067 and BE2022067-2)。
文摘In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically reviewed.In this context,general-ized odd-even mode theory is advanced to quantitatively and approximately describe the mutual coupling effect between a feed line and an antenna.As is mathematically deduced and demonstrated,the modal parity mismatch between the feed line and the antenna should ultimately dominate the unbalance phenomenon in antenna systems.Thus,an elegant,closed-form formula is derived to ap-proximately calculate the“unbalance degree”of a straight dipole off-center fed by a symmetric twin-wire line.Design approaches for the simplest,linear,1-D multimode resonant antennas are introduced.Moreover,the“falling tone excitation”law gauged based on prototype dipoles is revealed and used to develop a mode synthesis design approach for microstrip patch antennas(MPAs)and 2-D sectorial electric dipole antennas.Design examples with distinctive radiation performance are presented and discussed.Finally,possible development trends of multimode resonant antennas are prospected.
文摘Organizational corporate social responsibility is a good practice by organizations. Organizations engagement in corporate social responsibility programs may benefit the organization and stakeholders. The focus of this paper is to explore the extent of employees＇ engagement in the organization＇s corporate responsibility programs by utilizing Unerman＇s （2007） stakeholders engagement framework. The main research question is how employees engage themselves in corporate social responsibility programs. This study employs a case study research design approach. The findings have shown that there is empowerment between employees and the management in the corporate social responsibility programs. Their involvement appears from their feedbacks and views in the surveys as well as discussion with regards to corporate responsibility programs. All in all, employees＇ engagement is seen as an important practice in the organization, particularly in planning, implementing, monitoring, and reporting the corporate responsibility program.
文摘In 1999, the first International Maritime Confere- nce on Design for Safety was successfully held in Glasgow, UK as a WEGEMT Euro Conference with the sponsorship of the European Commission. Respo- nding to the expectation from the world maritime safety community, the second was held in 2004 in Japan. The third and fourth were held in USA, 2007 and Italy, 2010, respectively. This year the Design for Safety conference including a single event of the 4th Workshop on Risk-Based Approaches in the Marine Industries will be held in Shanghai on November 25- 27, 2013. The conference is organized by Shanghai Jiao Tong University and is co-organized/sponsored by Marine Design and Research Institute of China （MARIC） and China Classification Society （CCS~.
基金supported by the National Science Fund for Distinguished Young Scholars of China (Grant No. 10925212)National Natural Science Foundation of China (Grant Nos. 50775184,90916027)+1 种基金Aviation Science Foundation of China (Grant No. 2008ZA53007)Graduate Starting Seed Fund of Northwestern Polytechnical University (Grant No. Z200918)
文摘The squirrel-cage elastic support is one of the most important components of an aero-engine rotor system.A proper structural design will favor the static and dynamic performances of the system.In view of the deficiency of the current shape optimization techniques,a new mapping approach is proposed to define shape design variables based on the parametric equations of 3D curves and surfaces.It is then applied for the slot shape optimization of a squirrel-cage elastic support.To this end,an automatic design procedure that integrates the Genetic Algorithm (GA) is developed to solve the problem.Two typical examples with different shape constraints are considered.Numerical results provide reasonable optimum designs for the improvement of stiffness and strength of the squirrel-cage elastic support.
文摘A design-of-experiments methodology is used to develop a statistical model for the prediction of the hydrodynamics of a liquid–solid circulating fluidized bed. To illustrate the multilevel factorial design approach, a step by step methodology is taken to study the effects of the interactions among the independent factors considered on the performance variables. A multilevel full factorial design with three levels of the two factors and five levels of the third factor has been studied. Various statistical models such as the linear, two-factor interaction, quadratic, and cubic models are tested. The model has been developed to predict responses, viz., average solids holdup and solids circulation rate. The validity of the developed regression model is verified using the analysis of variance. Furthermore, the model developed was compared with an experimental dataset to assess its adequacy and reliability. This detailed statistical design methodology for non-linear systems considered here provides a very important tool for design and optimization in a cost-effective approach
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This work was supported by the EU H2020 programme under Grant 870935.
文摘Technology and design are increasingly recognized as important drivers of social innovation(SI).While new-age technologies can disrupt the realm of social innovation through resource-efficient solutions and multiple outcome benefits,the appliction of design thinking approaches and techniques can enhance the potential for SI through humancentered participatory processes and a socially shared vision and impact.Despite extensive research focusing on SI practices driven by technology and design respectively,few studies have concentrated on the synergistic effects of technology and design in the field of SI.This paper addresses this gap through an exploratory study on the incorporation and role of technology in the practice of design for SI.By applying the mapping approach to a sample of 81 Design-enabled Innovation(DEI)pilot projects in the DESIGNSCAPES project,the distribution,hosts and manifestations of technology footprints are identified,taking into account the multi-phase innovation processes and multifaceted role of design.Our findings suggest that in design-supported SI,technology can be integrated in a systematic and conventional manner across a range of domains related to people,interactions,contexts,and artefacts and that its interaction with design actions is highly dependent on the different roles of design,followed by a further discussion of a conceptual argument regarding the possible role of technology in supporting design for SI.Based on these findings and results,the article concludes with the limitations of the study and possible theoretical and managerial implications.
基金Hong Kong Research Grants Council Early Career Scheme(24208915)National Natural Science Foundation of China(NSFC)Research Grants Council of Hong Kong Joint Research Scheme(N_CUHK415/15)
文摘Parity–time(PT) symmetry has been demonstrated in the frame of classic optics. Its applications in laser science have resulted in unconventional control and manipulation of resonant modes. PT-symmetric periodic circular Bragg lasers were previously proposed. Analyses with a transfer-matrix method have shown their superior properties of reduced threshold and enhanced modal discrimination between the radial modes. However, the properties of the azimuthal modes were not analyzed, which restricts further development of circular Bragg lasers. Here, we adopt the coupled-mode theory to design and analyze chirped circular Bragg lasers with radial PT symmetry. The new structures possess more versatile modal control with further enhanced modal discrimination between the azimuthal modes. We also analyze azimuthally modulated circular Bragg lasers with radial PT symmetry, which are shown to achieve even higher modal discrimination.
