This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models ...This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models offer insights, they fall short in presenting a holistic view of complex urban challenges. System dynamics (SD) models that are often utilized to provide holistic, systematic understanding of a research subject, like the urban system, emerge as valuable tools, but data scarcity and theoretical inadequacy pose challenges. The research reviews relevant papers on recent SD model applications in urban sustainability since 2018, categorizing them based on nine key indicators. Among the reviewed papers, data limitations and model assumptions were identified as ma jor challenges in applying SD models to urban sustainability. This led to exploring the transformative potential of big data analytics, a rare approach in this field as identified by this study, to enhance SD models’ empirical foundation. Integrating big data could provide data-driven calibration, potentially improving predictive accuracy and reducing reliance on simplified assumptions. The paper concludes by advocating for new approaches that reduce assumptions and promote real-time applicable models, contributing to a comprehensive understanding of urban sustainability through the synergy of big data and SD models.展开更多
Large-scale quantum networks require dynamic and resource-efficient solutions to reduce system complexity with maintained security and performance to support growing number of users over large distances.Current encodi...Large-scale quantum networks require dynamic and resource-efficient solutions to reduce system complexity with maintained security and performance to support growing number of users over large distances.Current encoding schemes including time-bin,polarization,and orbital angular momentum,suffer from the lack of reconfigurability and thus scalability issues.Here,we demonstrate the first-time implementation of frequency-bin-encoded entanglement-based quantum key distribution and a reconfigurable distribution of entanglement using frequency-bin encoding.Specifically,we demonstrate a novel scalable frequency-bin basis analyzer module that allows for a passive random basis selection as a crucial step in quantum protocols,and importantly equips each user with a single detector rather than four detectors.This minimizes massively the resource overhead,reduces the dark count contribution,vulnerability to detector side-channel attacks,and the detector imbalance,hence providing an enhanced security.Our approach offers an adaptive frequency-multiplexing capability to increase the number of channels without hardware overhead,enabling increased secret key rate and reconfigurable multi-user operations.In perspective,our approach enables dynamic resource-minimized quantum key distribution among multiple users across diverse network topologies,and facilitates scalability to large-scale quantum networks.展开更多
Healthcare is indeed a complex service system, one requiring the technobiology approach of systems engineering to underpin its development as an integrated and adaptive system. In general, healthcare services are carr...Healthcare is indeed a complex service system, one requiring the technobiology approach of systems engineering to underpin its development as an integrated and adaptive system. In general, healthcare services are carried out with knowledge-intensive agents or components which work together as providers and consumers to create or co-produce value. Indeed, the engineering design of a healthcare system must recognize the fact that it is actually a complex integration of human-centered activities that is increasingly dependent on information technology and knowledge. Like any service system, healthcare can be considered to be a combination or recombination of three essential components - people （characterized by behaviors, values, knowledge, etc.）, processes （characterized by collaboration, customization, etc.） and products （characterized by software, hardware, infrastructures, etc.）. Thus, a healthcare system is an integrated and adaptive set of people, processes and products. It is, in essence, a system of systems which objectives are to enhance its efficiency （leading to greater interdependency） and effectiveness （leading to improved health）. Integration occurs over the physical, temporal, organizational and functional dimensions, while adaptation occurs over the monitoring, feedback, cybernetic and learning dimensions. In sum, such service systems as healthcare are indeed complex, especially due to the uncertainties associated with the human-centered aspects of these systems. Moreover, the system complexities can only be dealt with methods that enhance system integration and adaptation.展开更多
The ＂theory of self-similar oscillatory finite-time singularities＂ of Sornette reflects accurately the spatio-temporal evolution and trends of development of events and processes in complex systems approaching to th...The ＂theory of self-similar oscillatory finite-time singularities＂ of Sornette reflects accurately the spatio-temporal evolution and trends of development of events and processes in complex systems approaching to the singularities, and the effect of prediction for catastrophic events has been tested to be satisfactory. The authors take the contents of the chemical element tungsten as the carrier of positive feedback （or activator） in the ore formation, then try to apply the theory to studying and analyzing the onset and development of ore formation in the Dajishan （大吉山） tungsten ore area, Jiangxi （江西） Province, China. The results of the study show that during the spatio-temporal evolution from outside the ore area to its center, the contents of the chemical element tungsten and their loga- rithmic derivatives （local fractal dimension） manifest an obvious regularity： by way of the process of oscillation and the transition to power-law accelerating growth, they eventually approach the center of ore formation. The regularity makes clear that in the complex ore-forming system of the Dajishan tungsten ore deposit, the chemical element tungsten plays the role of carrier of positive and negative feedback, and by competing with each other, approaches to singularity in finite time by virtue of self-similar log-periodic oscillations and succeeded by power-law accelerating growth. In this way the onset of ore formation is realized. This regularity reflects correctly the dynamic process of ore formation of the studied ore deposit. The authors hold that Sornette＇s theory can be further applied to the prediction of perspective areas.展开更多
Concurrent dual-band transceiver system is widely used in conditions where transceivers are required to work in different bands at the same time.In order to miniaturize the concurrent dual-band transceiver system and ...Concurrent dual-band transceiver system is widely used in conditions where transceivers are required to work in different bands at the same time.In order to miniaturize the concurrent dual-band transceiver system and reduce the number of components in a transceiver,a novel receiver mixing structure with one frequency-divided local oscillator is proposed.Compared to traditional mixing architecture with two local oscillators,the proposed structure reduces a local oscillator and a bandpass filter.In addition,the output signal of proposed mixing architecture has a better error vector magnitude(EVM)performance.The proposed mixing architecture is described in detail;the method of local oscillator signal frequency selection and the applicable conditions of the proposed structure are derived through math formula;and the conclusions are demonstrated by experimental results.展开更多
基金sponsored by the U.S.Department of Housing and Urban Development(Grant No.NJLTS0027-22)The opinions expressed in this study are the authors alone,and do not represent the U.S.Depart-ment of HUD’s opinions.
文摘This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models offer insights, they fall short in presenting a holistic view of complex urban challenges. System dynamics (SD) models that are often utilized to provide holistic, systematic understanding of a research subject, like the urban system, emerge as valuable tools, but data scarcity and theoretical inadequacy pose challenges. The research reviews relevant papers on recent SD model applications in urban sustainability since 2018, categorizing them based on nine key indicators. Among the reviewed papers, data limitations and model assumptions were identified as ma jor challenges in applying SD models to urban sustainability. This led to exploring the transformative potential of big data analytics, a rare approach in this field as identified by this study, to enhance SD models’ empirical foundation. Integrating big data could provide data-driven calibration, potentially improving predictive accuracy and reducing reliance on simplified assumptions. The paper concludes by advocating for new approaches that reduce assumptions and promote real-time applicable models, contributing to a comprehensive understanding of urban sustainability through the synergy of big data and SD models.
基金Open Access funding enabled and organized by Projekt DEAL.
文摘Large-scale quantum networks require dynamic and resource-efficient solutions to reduce system complexity with maintained security and performance to support growing number of users over large distances.Current encoding schemes including time-bin,polarization,and orbital angular momentum,suffer from the lack of reconfigurability and thus scalability issues.Here,we demonstrate the first-time implementation of frequency-bin-encoded entanglement-based quantum key distribution and a reconfigurable distribution of entanglement using frequency-bin encoding.Specifically,we demonstrate a novel scalable frequency-bin basis analyzer module that allows for a passive random basis selection as a crucial step in quantum protocols,and importantly equips each user with a single detector rather than four detectors.This minimizes massively the resource overhead,reduces the dark count contribution,vulnerability to detector side-channel attacks,and the detector imbalance,hence providing an enhanced security.Our approach offers an adaptive frequency-multiplexing capability to increase the number of channels without hardware overhead,enabling increased secret key rate and reconfigurable multi-user operations.In perspective,our approach enables dynamic resource-minimized quantum key distribution among multiple users across diverse network topologies,and facilitates scalability to large-scale quantum networks.
文摘Healthcare is indeed a complex service system, one requiring the technobiology approach of systems engineering to underpin its development as an integrated and adaptive system. In general, healthcare services are carried out with knowledge-intensive agents or components which work together as providers and consumers to create or co-produce value. Indeed, the engineering design of a healthcare system must recognize the fact that it is actually a complex integration of human-centered activities that is increasingly dependent on information technology and knowledge. Like any service system, healthcare can be considered to be a combination or recombination of three essential components - people （characterized by behaviors, values, knowledge, etc.）, processes （characterized by collaboration, customization, etc.） and products （characterized by software, hardware, infrastructures, etc.）. Thus, a healthcare system is an integrated and adaptive set of people, processes and products. It is, in essence, a system of systems which objectives are to enhance its efficiency （leading to greater interdependency） and effectiveness （leading to improved health）. Integration occurs over the physical, temporal, organizational and functional dimensions, while adaptation occurs over the monitoring, feedback, cybernetic and learning dimensions. In sum, such service systems as healthcare are indeed complex, especially due to the uncertainties associated with the human-centered aspects of these systems. Moreover, the system complexities can only be dealt with methods that enhance system integration and adaptation.
基金supported by the Open Foundation of State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing (No. GPMR200842)
文摘The ＂theory of self-similar oscillatory finite-time singularities＂ of Sornette reflects accurately the spatio-temporal evolution and trends of development of events and processes in complex systems approaching to the singularities, and the effect of prediction for catastrophic events has been tested to be satisfactory. The authors take the contents of the chemical element tungsten as the carrier of positive feedback （or activator） in the ore formation, then try to apply the theory to studying and analyzing the onset and development of ore formation in the Dajishan （大吉山） tungsten ore area, Jiangxi （江西） Province, China. The results of the study show that during the spatio-temporal evolution from outside the ore area to its center, the contents of the chemical element tungsten and their loga- rithmic derivatives （local fractal dimension） manifest an obvious regularity： by way of the process of oscillation and the transition to power-law accelerating growth, they eventually approach the center of ore formation. The regularity makes clear that in the complex ore-forming system of the Dajishan tungsten ore deposit, the chemical element tungsten plays the role of carrier of positive and negative feedback, and by competing with each other, approaches to singularity in finite time by virtue of self-similar log-periodic oscillations and succeeded by power-law accelerating growth. In this way the onset of ore formation is realized. This regularity reflects correctly the dynamic process of ore formation of the studied ore deposit. The authors hold that Sornette＇s theory can be further applied to the prediction of perspective areas.
基金supported by the National Natural Science Foundations of China (61821001)
文摘Concurrent dual-band transceiver system is widely used in conditions where transceivers are required to work in different bands at the same time.In order to miniaturize the concurrent dual-band transceiver system and reduce the number of components in a transceiver,a novel receiver mixing structure with one frequency-divided local oscillator is proposed.Compared to traditional mixing architecture with two local oscillators,the proposed structure reduces a local oscillator and a bandpass filter.In addition,the output signal of proposed mixing architecture has a better error vector magnitude(EVM)performance.The proposed mixing architecture is described in detail;the method of local oscillator signal frequency selection and the applicable conditions of the proposed structure are derived through math formula;and the conclusions are demonstrated by experimental results.
