With the exceptional sensitivity of the Five-hundred-meter Aperture Spherical radio Telescope,we conducted observations of the neutral hydrogen(HⅠ)in the circumgalactic medium of Andromeda’s(M31)satellite galaxies,s...With the exceptional sensitivity of the Five-hundred-meter Aperture Spherical radio Telescope,we conducted observations of the neutral hydrogen(HⅠ)in the circumgalactic medium of Andromeda’s(M31)satellite galaxies,specifically AndromedaⅡ,NGC 205,and NGC 185.Initially,three drift scans were executed for these satellites,with a detection limit of 4×10^(18)cm^(-2)(approximately 1.88×10^(3)M_Θof HⅠmass),followed by a more in-depth scan of a specific region.We discovered a C-shaped HⅠarc structure sharing a position and line-of-sight velocity similar to a stellar ring structure around AndromedaⅡ,hinting at a potential connection with AndromedaⅡ.In the context of NGC 205,we identified two mass concentrations in the northeast direction,which could be indicative of tidal streams resulting from the interaction between this galaxy and M31.These new lumps discovered could be very helpful in solving the missing interstellar medium problem for NGC 205.Observations regarding NGC 185are consistent with previous studies,and we did not detect any additional HⅠmaterial around this galaxy.These observational results enhance our understanding of the evolution of these satellite galaxies and provide insight into their historical interactions with the galaxy M31.展开更多
Accurate flux density calibration is essential for precise analysis and interpretation of observations across different observation modes and instruments.In this research,we first introduce the flux calibration model ...Accurate flux density calibration is essential for precise analysis and interpretation of observations across different observation modes and instruments.In this research,we first introduce the flux calibration model that incorporated in Hi FAST pipeline,and designed for processing HⅠ21 cm spectra.Furthermore,we investigate different calibration techniques and assess the dependence of the gain parameter on the time and environmental factors.A comparison is carried out in various observation modes(e.g.,tracking and scanning modes)to determine the flux density gain(G),revealing insignificant discrepancies in G among different methods.Long-term monitoring data shows a linear correlation between G and atmospheric temperature.After subtracting the G-Temperature dependence,the dispersion of G is reduced to<3%over a one-year timescale.The stability of the receiver response of Five-hundred-meter Aperture Spherical radio Telescope(FAST)is considered sufficient to facilitate HⅠobservations that can accommodate a moderate error in flux calibration(e.g.,>~5%)when utilizing a constant G for calibration purposes.Our study will serve as a useful addition to the results provided by Jiang et al.Detailed measurement of G for the 19 beams of FAST,covering the frequency range 1000-1500 MHz,can be found on the Hi FAST homepage:https://hifast.readthedocs.io/fluxgain.展开更多
Somatic symptom disorder(SSD)is a new diagnosis introduced into the Diagnostic and Statistical Manual of Mental Disorders,Fifth Edition(DSM-5),which is expected to solve the diagnostic difficulties of patients with me...Somatic symptom disorder(SSD)is a new diagnosis introduced into the Diagnostic and Statistical Manual of Mental Disorders,Fifth Edition(DSM-5),which is expected to solve the diagnostic difficulties of patients with medically unexplained symptoms.Based on the previous work,this review aims to comprehensively synthesise updated evidence related to SSD from recent years in English publications and,more extensively,from data published in Chinese language journals.The scoping review update was based on an earlier scoping review and included Chinese language publication data from China National Knowledge Internet(CNKI),WANFANG and WEIPU between January 2013 and May 2022 and data from PubMed,PsyclNFO,and Cochrane Library between June 2020 and May 2022.Initially,2984 articles were identified,of which 63 full texts were included for analysis.In China,SSD is mainly applied in scientific research,but it also shows good predictive validity and clinical application potential.The mean frequency of SSD was 4.5%in the general population,25.2%in the primary care population and 33.5%in diverse specialised care settings.Biological factors,such as brain region changes and heart rate variability,are associated with the onset of sSD.Psychological impairment related to somatic symptoms is the best predictor of prognosis.While adolescent SSD is significantly associated with family function,SSD overall is associated with an increased dysfunction of cognition and emotion,decreased quality of life,and high comorbidity with anxiety and depressive disorders.Further research is needed on suicide risk and cultural and gender-related issues.Updating the data of Chinese language studies,our research enriches the evidence-based findings related to the topics addressed in the text sections of the SSD chapter of DSM-5.However,research gaps remain about SSD reliability,population-based prevalence,suicide risk,and cultural and gender-related issues.展开更多
Social Internet of Vehicles(SIoV)falls under the umbrella of social Internet of Things(IoT),where vehicles are socially connected to other vehicles and roadside units that can reliably share information and services w...Social Internet of Vehicles(SIoV)falls under the umbrella of social Internet of Things(IoT),where vehicles are socially connected to other vehicles and roadside units that can reliably share information and services with other social entities by leveraging the capabilities of 5G technology,which brings new opportunities and challenges,e.g.,collaborative power trading can address the mileage anxiety of electric vehicles.However,it relies on a trusted central party for scheduling,which introduces performance bottlenecks and cannot be set up in a distributed network,in addition,the lack of transparency in state-of-the-art Vehicle-to-Vehicle(V2V)power trading schemes can introduce further trust issues.In this paper,we propose a blockchain-based trustworthy collaborative power trading scheme for 5G-enabled social vehicular networks that uses a distributed market mechanism to introduce trusted power trading and avoids the dependence on a centralized dispatch center.Based on the game theory,we design the pricing and trading matching mechanism for V2V power trading to obtain maximum social welfare.We use blockchain to record power trading data for trusted pricing and use smart contracts for transaction matching.The simulation results verify the effectiveness of the proposed scheme in improving social welfare and reducing the load on the grid.展开更多
In radio astronomy,radio frequency interference(RFI)becomes more and more serious for radio observational facilities.The RFI always influences the search and study of the interesting astronomical objects.Mitigating th...In radio astronomy,radio frequency interference(RFI)becomes more and more serious for radio observational facilities.The RFI always influences the search and study of the interesting astronomical objects.Mitigating the RFI becomes an essential procedure in any survey data processing.The Five-hundred-meter Aperture Spherical radio Telescope(FAST)is an extremely sensitive radio telescope.It is necessary to find out an effective and precise RFI mitigation method for FAST data processing.In this work,we introduce a method to mitigate the RFI in FAST spectral observation and make a statistic for the RFI using~300 h FAST data.The details are as follows.First,according to the characteristics of FAST spectra,we propose to use the Asymmetrically Reweighted Penalized Least Squares algorithm for baseline fitting.Our test results show that it has a good performance.Second,we flag the RFI with four strategies,which are to flag extremely strong RFI,flag long-lasting RFI,flag polarized RFI,and flag beam-combined RFI,respectively.The test results show that all the RFI above a preset threshold could be flagged.Third,we make a statistic for the probabilities of polarized XX and YY RFI in FAST observations.The statistical results could tell us which frequencies are relatively quiescent.With such statistical data,we are able to avoid using such frequencies in our spectral observations.Finally,based on the~300 h FAST data,we obtained an RFI table,which is the most complete database currently for FAST.展开更多
Purpose:As smartphones become ubiquitous,it is important to understand emerging information behavior as a result of wide spread use of smartphones.The purpose of this study is to investigate information behavior in th...Purpose:As smartphones become ubiquitous,it is important to understand emerging information behavior as a result of wide spread use of smartphones.The purpose of this study is to investigate information behavior in the mobile environment by studying undergraduate smartphone users in China.Design/methodology/approach:This study is based on a survey of 205 undergraduate students in China.Findings:Smartphones are used predominantly for accessing news and connecting to social media,rather than for academic purposes such as accessing library resources or researching.While students use smartphones for reading e-books,much of this reading is recreational during their spare time.Research limitations:The inherent limitations of self-reported measures and the small sample size of this study mean that the results cannot be generalized across different age groups and cultures.Practical implications:When targeting users on the move,information professionals should be aware that the needs and behaviors of smartphone readers are significantly different compared to users of fixed devices,and should provide services in a mobile-friendly way.Originality/value:The younger generation is accustomed to instant information access.For libraries to relevant,they must redesign their services.It is important for libraries to leverage the strengths of mobile technology and to balance traditional services with mobile delivery.Even though many mobile users will use desktop or laptop computers to access library resources,they will benefit from the availability of mobile-friendly library services.展开更多
Purpose: Digital reading is an important research topic in contemporary information science research. This paper aims to provide a snapshot of major studies on digital reading over the past few years.Design/methodolog...Purpose: Digital reading is an important research topic in contemporary information science research. This paper aims to provide a snapshot of major studies on digital reading over the past few years.Design/methodology/approach: This paper begins by introducing the background in digital reading, then outlines major research findings.Findings: The paper demonstrates the growth of interest in information science and other disciplines in digital reading behavior. Five areas are highlighted: Digital reading behavior,print vs. digital, preference for reading medium, multi-tasking and learning, and technological advancement and traditional attachment.Research limitations: Only major studies in the North American and European countries are covered.Practical implications: Understanding reading behavior in the digital environment would help develop more effective reading devices and empower readers in the online environment.Originality/value: The paper represents a first attempt to compare, evaluate, and synthesize recent studies on digital reading. Implications for the changes in reading behavior are discussed, and directions for future research are suggested.展开更多
The paper analyses the necessity of government playing a role in the economic transformation and the government function in the process of economic transformation to definite the role of state government of China in t...The paper analyses the necessity of government playing a role in the economic transformation and the government function in the process of economic transformation to definite the role of state government of China in the process of economy transformation.展开更多
Purpose: This paper attempts to examine perceived benefits,barriers,and students' reactions towards e-textbooks.Design/methodology/approach: This study is based on a survey of 105 undergraduate students in Califor...Purpose: This paper attempts to examine perceived benefits,barriers,and students' reactions towards e-textbooks.Design/methodology/approach: This study is based on a survey of 105 undergraduate students in California. Undergraduate students were selected as the subjects of this study,because they are heavy users of textbooks for their course work.Findings: E-textbooks will complement our existing choices rather than substitute printed textbooks. While e-textbooks offer a number of benefits,they also produce many unanticipated challenges. A number of critical hurdles need to be solved before wider acceptance.Research limitations: This study attempts to explore students' reactions to e-textbooks by targeting undergraduate students in California. Future studies can focus on the long-term effects on learning.Practical implications: Considerable attention should be paid to designing features to ensure e-textbooks augment learning rather than detract from it.Originality/value: This paper also looks at the extent to which e-reader users and none e-reader users differ in their preferences for traditional textbooks and e-textbooks.展开更多
The FAST All Sky HI survey(FASHI)was designed to cover the entire sky observable by the Five-hundred-meter Aperture Spherical radio Telescope(FAST),spanning approximately 22000 square degrees of declination between-14...The FAST All Sky HI survey(FASHI)was designed to cover the entire sky observable by the Five-hundred-meter Aperture Spherical radio Telescope(FAST),spanning approximately 22000 square degrees of declination between-14°and+66°,and in the frequency range of 1050-1450 MHz,with the expectation of eventually detecting more than 100000 HI sources.Between August 2020 and June 2023,FASHI had covered more than 7600 square degrees,which is approximately 35%of the total sky observable by FAST.It has a median detection sensitivity of around 0.76 m Jy beam-1and a spectral line velocity resolution of~6.4 km s-1at a frequency of~1.4 GHz.As of now,a total of 41741 extragalactic HI sources have been detected in the frequency range 1305.5-1419.5 MHz,corresponding to a redshift limit of z■0.09.By cross-matching FASHI sources with the Siena Galaxy Atlas(SGA)and the Sloan Digital Sky Survey(SDSS)catalogs,we found that 16972(40.7%)sources have spectroscopic redshifts and 10975(26.3%)sources have only photometric redshifts.Most of the remaining 13794(33.0%)HI sources are located in the direction of the Galactic plane,making their optical counterparts difficult to identify due to high extinction or high contamination of Galactic stellar sources.Based on current survey results,the FASHI survey is an unprecedented blind extragalactic H I survey.It has higher spectral and spatial resolution and broader coverage than the Arecibo Legacy Fast ALFA Survey(ALFALFA).When completed,FASHI will provide the largest extragalactic HI catalog and an objective view of HI content and large-scale structure in the local universe.展开更多
Battery energy storage systems(BESSs)serve a crucial role in balancing energy fluctuations and reducing carbon emissions in net-zero power systems.However,the efficiency and cost performance have remained significant ...Battery energy storage systems(BESSs)serve a crucial role in balancing energy fluctuations and reducing carbon emissions in net-zero power systems.However,the efficiency and cost performance have remained significant challenges,which hinders the widespread adoption and development of BESSs.To address these challenges,this paper proposes a real-time energy management scheme that considers the involvement of prosumers to support net-zero power systems.The scheme is based on two shared energy storage models,referred to as energy storage sale model and power line lease model.The energy storage sale model balances real-time power deviations by energy interaction with the goal of minimizing system costs while generating revenue for shared energy storage providers(ESPs).Additionally,power line lease model supports peer-to-peer(P2P)power trading among prosumers through the power lines laid by ESPs to connect each prosumer.This model allows ESP to earn profits from the use of power lines while balancing power deviations and better consuming renewable energy.Experimental results validate the effectiveness of the proposed scheme,ensuring stable power supply for net-zero power systems and providing benefits for both the ESP and prosumers.展开更多
The Five-hundred-meter Aperture Spherical radio Telescope(FAST)has the largest aperture and a 19-beam L-band receiver,making it powerful for investigating the neutral hydrogen atomic gas(HI)in the universe.We present ...The Five-hundred-meter Aperture Spherical radio Telescope(FAST)has the largest aperture and a 19-beam L-band receiver,making it powerful for investigating the neutral hydrogen atomic gas(HI)in the universe.We present HiFAST(https://hifast.readthedocs.io),a dedicated,modular,and self-contained calibration and imaging pipeline for processing the H?data of FAST.The pipeline consists of frequency-dependent noise diode calibration,baseline fitting,standing wave removal using an FFT-based method,flux density calibration,stray radiation correction,and gridding to produce data cubes.These modules can be combined as needed to process the data from most FAST observation modes:tracking,drift scanning,On-The-Fly mapping,and most of their variants.With HiFAST,the root-mean-square(RMS)noises of the calibrated spectra from all 19 beams were only slightly(~5%)higher than the theoretical expectation.The results for the extended source M33 and the point sources are consistent with the results from Arecibo.The moment maps(0,1 and 2)of M33 agree well with the results from the Arecibo Galaxy Environment Survey(AGES)with a fractional difference of less than 10%.For a common sample of 221 sources with signal-to-noise ratio S/N>10 from the Arecibo Legacy Fast ALFA(ALFALFA)survey,the mean value of fractional difference in the integrated flux density,Sint,between the two datasets is approximately 0.005%,with a dispersion of 15.4%.Further checks on the integrated flux density of 23 sources with seven observations indicate that the variance in the flux density of the source with luminous objects(Sint>2.5 Jy km s-1)is less than 5%.Our tests suggest that the FAST telescope,with the efficient,precise,and user-friendly pipeline HiFAST,will yield numerous significant scientific findings in the investigation of the H?in the universe.展开更多
The authors regret that following the publication of the original article,the authors noticed that Funds in Acknowledgements section was incorrect,in which a fund(No.2020YFA0906903)supporting most of experimental resu...The authors regret that following the publication of the original article,the authors noticed that Funds in Acknowledgements section was incorrect,in which a fund(No.2020YFA0906903)supporting most of experimental results of Dr.Xinmao Chen was missed by us.We sincerely apologize again for the oversight and appreciate your understanding in allowing us to correct this matter.展开更多
Cooperative activation is critical for the applications of synthetic biology in mammalian cells.In this study,we have developed cooperative transcription factor by fusing oligomerization domain in mammalian cells.Firs...Cooperative activation is critical for the applications of synthetic biology in mammalian cells.In this study,we have developed cooperative transcription factor by fusing oligomerization domain in mammalian cells.Firstly,we demonstrated that two oligomerized domains(CI434 and CI)successfully improved transcription factor cooperativity in bacterial cells but failed to increase cooperativity in mammalian cells,possibly because the additional mammalian activation domain disrupted their oligomerization capability.Therefore,we chose a different type of oligomerized domain(CarHC),whose ability to oligomerize is not dependent on its C-terminal domains,to fuse with a transcription factor(RpaR)and activation domain(VTR3),forming a potential cooperative transcription activator RpaR-CarH-VTR3 for mammalian regulatory systems.Compared with RpaR-VTR3,the cooperativity of RpaR-CarH-VTR3 was significantly improved with higher Hill coefficient and a narrower input range in the inducible switch system in mammalian cells.Moreover,a mathematical model based on statistical mechanics model was developed and the simulation results supported the hypothesis that the tetramer of the CarH domain in mammalian cells was the reason for the cooperative capacity of RpaR-CarH-VTR3.展开更多
基金support of the China National Key Program for Science and Technology Research and Development of China(2022YFA1602901)the National Natural Science Foundation of China(NSFC,Grant Nos.11988101 and 11873051)+3 种基金the CAS Project for Young Scientists in Basic Research grant(No.YSBR-062)the K.C.Wong Education Foundationthe science research grants from the China Manned Space Projectsupport from the Cultivation Project for FAST Scientific Payoff and Research Achievement of CAMS-CAS。
文摘With the exceptional sensitivity of the Five-hundred-meter Aperture Spherical radio Telescope,we conducted observations of the neutral hydrogen(HⅠ)in the circumgalactic medium of Andromeda’s(M31)satellite galaxies,specifically AndromedaⅡ,NGC 205,and NGC 185.Initially,three drift scans were executed for these satellites,with a detection limit of 4×10^(18)cm^(-2)(approximately 1.88×10^(3)M_Θof HⅠmass),followed by a more in-depth scan of a specific region.We discovered a C-shaped HⅠarc structure sharing a position and line-of-sight velocity similar to a stellar ring structure around AndromedaⅡ,hinting at a potential connection with AndromedaⅡ.In the context of NGC 205,we identified two mass concentrations in the northeast direction,which could be indicative of tidal streams resulting from the interaction between this galaxy and M31.These new lumps discovered could be very helpful in solving the missing interstellar medium problem for NGC 205.Observations regarding NGC 185are consistent with previous studies,and we did not detect any additional HⅠmaterial around this galaxy.These observational results enhance our understanding of the evolution of these satellite galaxies and provide insight into their historical interactions with the galaxy M31.
基金the support of the China National Key Program for Science and Technology Research and Development of China(2022YFA1602901,2023YFA1608204)the National Natural Science Foundation of China(Nos.11988101,11873051,12125302,12373011,12041305,12173016)the CAS Project for Young Scientists in Basic Research grant(No.YSBR-062)。
文摘Accurate flux density calibration is essential for precise analysis and interpretation of observations across different observation modes and instruments.In this research,we first introduce the flux calibration model that incorporated in Hi FAST pipeline,and designed for processing HⅠ21 cm spectra.Furthermore,we investigate different calibration techniques and assess the dependence of the gain parameter on the time and environmental factors.A comparison is carried out in various observation modes(e.g.,tracking and scanning modes)to determine the flux density gain(G),revealing insignificant discrepancies in G among different methods.Long-term monitoring data shows a linear correlation between G and atmospheric temperature.After subtracting the G-Temperature dependence,the dispersion of G is reduced to<3%over a one-year timescale.The stability of the receiver response of Five-hundred-meter Aperture Spherical radio Telescope(FAST)is considered sufficient to facilitate HⅠobservations that can accommodate a moderate error in flux calibration(e.g.,>~5%)when utilizing a constant G for calibration purposes.Our study will serve as a useful addition to the results provided by Jiang et al.Detailed measurement of G for the 19 beams of FAST,covering the frequency range 1000-1500 MHz,can be found on the Hi FAST homepage:https://hifast.readthedocs.io/fluxgain.
文摘Somatic symptom disorder(SSD)is a new diagnosis introduced into the Diagnostic and Statistical Manual of Mental Disorders,Fifth Edition(DSM-5),which is expected to solve the diagnostic difficulties of patients with medically unexplained symptoms.Based on the previous work,this review aims to comprehensively synthesise updated evidence related to SSD from recent years in English publications and,more extensively,from data published in Chinese language journals.The scoping review update was based on an earlier scoping review and included Chinese language publication data from China National Knowledge Internet(CNKI),WANFANG and WEIPU between January 2013 and May 2022 and data from PubMed,PsyclNFO,and Cochrane Library between June 2020 and May 2022.Initially,2984 articles were identified,of which 63 full texts were included for analysis.In China,SSD is mainly applied in scientific research,but it also shows good predictive validity and clinical application potential.The mean frequency of SSD was 4.5%in the general population,25.2%in the primary care population and 33.5%in diverse specialised care settings.Biological factors,such as brain region changes and heart rate variability,are associated with the onset of sSD.Psychological impairment related to somatic symptoms is the best predictor of prognosis.While adolescent SSD is significantly associated with family function,SSD overall is associated with an increased dysfunction of cognition and emotion,decreased quality of life,and high comorbidity with anxiety and depressive disorders.Further research is needed on suicide risk and cultural and gender-related issues.Updating the data of Chinese language studies,our research enriches the evidence-based findings related to the topics addressed in the text sections of the SSD chapter of DSM-5.However,research gaps remain about SSD reliability,population-based prevalence,suicide risk,and cultural and gender-related issues.
基金supported in part by the National Natural Science Foundation of China (No.62002113)the Natural Science Foundation of Hunan Province (No. 2021JJ40122).
文摘Social Internet of Vehicles(SIoV)falls under the umbrella of social Internet of Things(IoT),where vehicles are socially connected to other vehicles and roadside units that can reliably share information and services with other social entities by leveraging the capabilities of 5G technology,which brings new opportunities and challenges,e.g.,collaborative power trading can address the mileage anxiety of electric vehicles.However,it relies on a trusted central party for scheduling,which introduces performance bottlenecks and cannot be set up in a distributed network,in addition,the lack of transparency in state-of-the-art Vehicle-to-Vehicle(V2V)power trading schemes can introduce further trust issues.In this paper,we propose a blockchain-based trustworthy collaborative power trading scheme for 5G-enabled social vehicular networks that uses a distributed market mechanism to introduce trusted power trading and avoids the dependence on a centralized dispatch center.Based on the game theory,we design the pricing and trading matching mechanism for V2V power trading to obtain maximum social welfare.We use blockchain to record power trading data for trusted pricing and use smart contracts for transaction matching.The simulation results verify the effectiveness of the proposed scheme in improving social welfare and reducing the load on the grid.
基金supported by the National Key R&D Program of China(2018YFE0202900)support by the NAOC Nebula Talents Program and the Cultivation Project for FAST Scientific Payoff and Research Achievement of CAMS-CAS。
文摘In radio astronomy,radio frequency interference(RFI)becomes more and more serious for radio observational facilities.The RFI always influences the search and study of the interesting astronomical objects.Mitigating the RFI becomes an essential procedure in any survey data processing.The Five-hundred-meter Aperture Spherical radio Telescope(FAST)is an extremely sensitive radio telescope.It is necessary to find out an effective and precise RFI mitigation method for FAST data processing.In this work,we introduce a method to mitigate the RFI in FAST spectral observation and make a statistic for the RFI using~300 h FAST data.The details are as follows.First,according to the characteristics of FAST spectra,we propose to use the Asymmetrically Reweighted Penalized Least Squares algorithm for baseline fitting.Our test results show that it has a good performance.Second,we flag the RFI with four strategies,which are to flag extremely strong RFI,flag long-lasting RFI,flag polarized RFI,and flag beam-combined RFI,respectively.The test results show that all the RFI above a preset threshold could be flagged.Third,we make a statistic for the probabilities of polarized XX and YY RFI in FAST observations.The statistical results could tell us which frequencies are relatively quiescent.With such statistical data,we are able to avoid using such frequencies in our spectral observations.Finally,based on the~300 h FAST data,we obtained an RFI table,which is the most complete database currently for FAST.
文摘Purpose:As smartphones become ubiquitous,it is important to understand emerging information behavior as a result of wide spread use of smartphones.The purpose of this study is to investigate information behavior in the mobile environment by studying undergraduate smartphone users in China.Design/methodology/approach:This study is based on a survey of 205 undergraduate students in China.Findings:Smartphones are used predominantly for accessing news and connecting to social media,rather than for academic purposes such as accessing library resources or researching.While students use smartphones for reading e-books,much of this reading is recreational during their spare time.Research limitations:The inherent limitations of self-reported measures and the small sample size of this study mean that the results cannot be generalized across different age groups and cultures.Practical implications:When targeting users on the move,information professionals should be aware that the needs and behaviors of smartphone readers are significantly different compared to users of fixed devices,and should provide services in a mobile-friendly way.Originality/value:The younger generation is accustomed to instant information access.For libraries to relevant,they must redesign their services.It is important for libraries to leverage the strengths of mobile technology and to balance traditional services with mobile delivery.Even though many mobile users will use desktop or laptop computers to access library resources,they will benefit from the availability of mobile-friendly library services.
文摘Purpose: Digital reading is an important research topic in contemporary information science research. This paper aims to provide a snapshot of major studies on digital reading over the past few years.Design/methodology/approach: This paper begins by introducing the background in digital reading, then outlines major research findings.Findings: The paper demonstrates the growth of interest in information science and other disciplines in digital reading behavior. Five areas are highlighted: Digital reading behavior,print vs. digital, preference for reading medium, multi-tasking and learning, and technological advancement and traditional attachment.Research limitations: Only major studies in the North American and European countries are covered.Practical implications: Understanding reading behavior in the digital environment would help develop more effective reading devices and empower readers in the online environment.Originality/value: The paper represents a first attempt to compare, evaluate, and synthesize recent studies on digital reading. Implications for the changes in reading behavior are discussed, and directions for future research are suggested.
文摘The paper analyses the necessity of government playing a role in the economic transformation and the government function in the process of economic transformation to definite the role of state government of China in the process of economy transformation.
文摘Purpose: This paper attempts to examine perceived benefits,barriers,and students' reactions towards e-textbooks.Design/methodology/approach: This study is based on a survey of 105 undergraduate students in California. Undergraduate students were selected as the subjects of this study,because they are heavy users of textbooks for their course work.Findings: E-textbooks will complement our existing choices rather than substitute printed textbooks. While e-textbooks offer a number of benefits,they also produce many unanticipated challenges. A number of critical hurdles need to be solved before wider acceptance.Research limitations: This study attempts to explore students' reactions to e-textbooks by targeting undergraduate students in California. Future studies can focus on the long-term effects on learning.Practical implications: Considerable attention should be paid to designing features to ensure e-textbooks augment learning rather than detract from it.Originality/value: This paper also looks at the extent to which e-reader users and none e-reader users differ in their preferences for traditional textbooks and e-textbooks.
基金supported by the National Key R&D Program of China(Grant Nos.2018YFE0202900,and 2022YFA1602901)support by the West Light Foundation of the Chinese Academy of Sciences(CAS)+4 种基金supported by the National Natural Science Foundation of China(Grant Nos.11803044,11933003,and 12173045)sponsored(in part)by the CAS,through a grant to the CAS South America Center for Astronomy(CASSACA)the science research grants from the China Manned Space Project(Grant No.CMS-CSST-2021-A05)Funding for the Sloan Digital Sky SurveyⅣhas been provided by the Alfred P.Sloan Foundation,the U.S.Department of Energy Office of Science,and the Participating Institutionssupport and resources from the Center for High-Performance Computing at the University of Utah。
文摘The FAST All Sky HI survey(FASHI)was designed to cover the entire sky observable by the Five-hundred-meter Aperture Spherical radio Telescope(FAST),spanning approximately 22000 square degrees of declination between-14°and+66°,and in the frequency range of 1050-1450 MHz,with the expectation of eventually detecting more than 100000 HI sources.Between August 2020 and June 2023,FASHI had covered more than 7600 square degrees,which is approximately 35%of the total sky observable by FAST.It has a median detection sensitivity of around 0.76 m Jy beam-1and a spectral line velocity resolution of~6.4 km s-1at a frequency of~1.4 GHz.As of now,a total of 41741 extragalactic HI sources have been detected in the frequency range 1305.5-1419.5 MHz,corresponding to a redshift limit of z■0.09.By cross-matching FASHI sources with the Siena Galaxy Atlas(SGA)and the Sloan Digital Sky Survey(SDSS)catalogs,we found that 16972(40.7%)sources have spectroscopic redshifts and 10975(26.3%)sources have only photometric redshifts.Most of the remaining 13794(33.0%)HI sources are located in the direction of the Galactic plane,making their optical counterparts difficult to identify due to high extinction or high contamination of Galactic stellar sources.Based on current survey results,the FASHI survey is an unprecedented blind extragalactic H I survey.It has higher spectral and spatial resolution and broader coverage than the Arecibo Legacy Fast ALFA Survey(ALFALFA).When completed,FASHI will provide the largest extragalactic HI catalog and an objective view of HI content and large-scale structure in the local universe.
基金supported in part by the National Key Research and Development Program of China(No.2018YFA0702200)the National Natural Science Foundation of China(No.52377079)the Liaoning Revitalization Talents Program(No.XLYC2007181)。
文摘Battery energy storage systems(BESSs)serve a crucial role in balancing energy fluctuations and reducing carbon emissions in net-zero power systems.However,the efficiency and cost performance have remained significant challenges,which hinders the widespread adoption and development of BESSs.To address these challenges,this paper proposes a real-time energy management scheme that considers the involvement of prosumers to support net-zero power systems.The scheme is based on two shared energy storage models,referred to as energy storage sale model and power line lease model.The energy storage sale model balances real-time power deviations by energy interaction with the goal of minimizing system costs while generating revenue for shared energy storage providers(ESPs).Additionally,power line lease model supports peer-to-peer(P2P)power trading among prosumers through the power lines laid by ESPs to connect each prosumer.This model allows ESP to earn profits from the use of power lines while balancing power deviations and better consuming renewable energy.Experimental results validate the effectiveness of the proposed scheme,ensuring stable power supply for net-zero power systems and providing benefits for both the ESP and prosumers.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1602901)the National Natural Science Foundation of China(Grant Nos.11988101,11873051,12125302,and 12373011)+3 种基金the CAS Project for Young Scientists in Basic Research Grant(Grant No.YSBR-062)the K.C.Wong Education Foundationthe science research grants from the China Manned Space Projectsupport from the Cultivation Project for FAST Scientific Payoff and Research Achievement of CAMS-CAS。
文摘The Five-hundred-meter Aperture Spherical radio Telescope(FAST)has the largest aperture and a 19-beam L-band receiver,making it powerful for investigating the neutral hydrogen atomic gas(HI)in the universe.We present HiFAST(https://hifast.readthedocs.io),a dedicated,modular,and self-contained calibration and imaging pipeline for processing the H?data of FAST.The pipeline consists of frequency-dependent noise diode calibration,baseline fitting,standing wave removal using an FFT-based method,flux density calibration,stray radiation correction,and gridding to produce data cubes.These modules can be combined as needed to process the data from most FAST observation modes:tracking,drift scanning,On-The-Fly mapping,and most of their variants.With HiFAST,the root-mean-square(RMS)noises of the calibrated spectra from all 19 beams were only slightly(~5%)higher than the theoretical expectation.The results for the extended source M33 and the point sources are consistent with the results from Arecibo.The moment maps(0,1 and 2)of M33 agree well with the results from the Arecibo Galaxy Environment Survey(AGES)with a fractional difference of less than 10%.For a common sample of 221 sources with signal-to-noise ratio S/N>10 from the Arecibo Legacy Fast ALFA(ALFALFA)survey,the mean value of fractional difference in the integrated flux density,Sint,between the two datasets is approximately 0.005%,with a dispersion of 15.4%.Further checks on the integrated flux density of 23 sources with seven observations indicate that the variance in the flux density of the source with luminous objects(Sint>2.5 Jy km s-1)is less than 5%.Our tests suggest that the FAST telescope,with the efficient,precise,and user-friendly pipeline HiFAST,will yield numerous significant scientific findings in the investigation of the H?in the universe.
文摘The authors regret that following the publication of the original article,the authors noticed that Funds in Acknowledgements section was incorrect,in which a fund(No.2020YFA0906903)supporting most of experimental results of Dr.Xinmao Chen was missed by us.We sincerely apologize again for the oversight and appreciate your understanding in allowing us to correct this matter.
基金supported by Ministry of Science and Technology of China [No.2021YFA0910700,2021YFF1200500,2020YFA0907101]the Natural Science Foundation of China [No.12090050,12090054,32071412]+1 种基金the Chinese Academy of Sciences [No.QYZDB-SSW-SMC050]CAS Youth Interdisciplinary Team and the Shenzhen Science and Technology Innovation Committee [No.JCYJ20180507182241844,JCHZ20200005,DWKF20190009].
文摘Cooperative activation is critical for the applications of synthetic biology in mammalian cells.In this study,we have developed cooperative transcription factor by fusing oligomerization domain in mammalian cells.Firstly,we demonstrated that two oligomerized domains(CI434 and CI)successfully improved transcription factor cooperativity in bacterial cells but failed to increase cooperativity in mammalian cells,possibly because the additional mammalian activation domain disrupted their oligomerization capability.Therefore,we chose a different type of oligomerized domain(CarHC),whose ability to oligomerize is not dependent on its C-terminal domains,to fuse with a transcription factor(RpaR)and activation domain(VTR3),forming a potential cooperative transcription activator RpaR-CarH-VTR3 for mammalian regulatory systems.Compared with RpaR-VTR3,the cooperativity of RpaR-CarH-VTR3 was significantly improved with higher Hill coefficient and a narrower input range in the inducible switch system in mammalian cells.Moreover,a mathematical model based on statistical mechanics model was developed and the simulation results supported the hypothesis that the tetramer of the CarH domain in mammalian cells was the reason for the cooperative capacity of RpaR-CarH-VTR3.