The evolution of global mobile data over the past decades in broadcasting, Internet of Things (IoT), education, healthcare, commerce, and energy has put strong pressure on 3G/4G mobile networks to improve their servic...The evolution of global mobile data over the past decades in broadcasting, Internet of Things (IoT), education, healthcare, commerce, and energy has put strong pressure on 3G/4G mobile networks to improve their service offerings. These generations of mobile networks were initially invented to meet the requirements of the above-mentioned applications. However, as the requirements in these applications continue to increase, new mobile technologies such as 5G (fifth generation), 5G and beyond (B5G, beyond fifth generation), and 6G (sixth generation) are still progressing and being experimented. These networks are very heterogeneous generations of mobile networks that will have to offer very high throughput per user, good energy efficiency, better traffic capacity per area, improved spectral efficiency, very low latency, and high mobility. To meet these requirements, the radio interface of future mobile networks will have to be flexible and rationalized the available frequency resources. Therefore, new modulation methods, access techniques and waveforms capable of supporting these technological changes are proposed. This review presents brief descriptions of the types of 5G, B5G, and 6G waveforms. The 5G consists of OFDM including its transmission techniques: generalized frequency division multiplexing (GFDM), filter bank based multi-carrier (FBMC), universal filtered multi-carrier (UFMC), and index modulation (IM). Meanwhile, the 6G covers orthogonal time frequency space (OTFS), orthogonal chirp division multiplexing (OCDM) and orthogonal time sequence multiplexing (OTSM). The networks’ potentialities, advantages, disadvantages, and future directions are outlined.展开更多
This study comprehensively reviews the literature to deeply explore the role of computer science and internet technologies in addressing educational inequality and socio-psychological issues,with a particular focus on...This study comprehensively reviews the literature to deeply explore the role of computer science and internet technologies in addressing educational inequality and socio-psychological issues,with a particular focus on applications of 5G,artificial intelligence(AI),and augmented/virtual reality(AR/VR).By analyzing how these technologies are reshaping learning and their potential to ameliorate educational disparities,the study reveals challenges present in ensuring educational equity.The research methodology includes exhaustive reviews of applications of AI and machine learning,the Internet of Things and wearable technologies integration,big data analytics and data mining,and the effects of online platforms and social media on socio-psychological issues.Besides,the study discusses applications of these technologies in educational inequality and socio-psychological problem-solving through the lens of 5G,AI,and AR/VR,while also delineating challenges faced by these emerging technologies and future outlooks.The study finds that while computer science and internet technologies hold promise to bridge academic divides and address socio-psychological problems,the complexity of technology access and infrastructure,lack of digital literacy and skills,and critical ethical and privacy issues can impact widespread adoption and efficacy.Overall,the study provides a novel perspective to understand the potential of computer science and internet technologies in ameliorating educational inequality and socio-psychological issues,while pointing to new directions for future research.It also emphasizes the importance of cooperation among educational institutions,technology vendors,policymakers and researchers,and establishing comprehensive ethical guidelines and regulations to ensure the responsible use of these technologies.展开更多
Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user ...Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of B5G.The multiwatermarking process employs spread transform dither modulation.During the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading vectors.Consequently,multiple watermarks can be simultaneously embedded into the same position of a multimedia signal.Moreover,the multiple watermarks can be extracted without affecting one another during the extraction process.We analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility.展开更多
Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so t...Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so that the communication distance is short.In this paper,we first calculate the communication distance upper bounds for both uplink and downlink by measuring the tag sensitivity and reflection coefficient.It is found that the activation voltage of the envelope detection diode of the downlink tag is the main factor limiting the back-scatter communication distance.Based on this analysis,we then propose to implement a low-noise amplifier(LNA)module before the envelope detection at the tag to enhance the incident signal strength.Our experimental results on the hardware platform show that our method can increase the downlink communication range by nearly 20 m.展开更多
Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems...Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in construction.This paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within 6G.Based on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.展开更多
On the basis of analyzing both domestic and foreign evaluation systems for the e-government and also taking into account of the current situation of government portals in urban centers,the paper is aimed to construct ...On the basis of analyzing both domestic and foreign evaluation systems for the e-government and also taking into account of the current situation of government portals in urban centers,the paper is aimed to construct an evaluation system primarily for the measurement of the service capability of business-oriented G2B portals of local governments in general and those G2B portals of the new development zones in particular.This system is composed of 6 first tier indicators,18 second tier indicators and 90 third tier indicators.And the weight of each indicator is determined by Delphi Method and Analytic Hierarchy Process(AHP) Method.Subsequently,we used this system to evaluate the government portals of Tianjin Binhai New Area and Shanghai Pudong New Area and proved to have the desired practicability.展开更多
Compared with the services in 3G, services in Beyond 3G (B3G) have some distinctive characteristics such as the packet data services being the majority, more service types, larger scale of services, higher peak transm...Compared with the services in 3G, services in Beyond 3G (B3G) have some distinctive characteristics such as the packet data services being the majority, more service types, larger scale of services, higher peak transmission rate, enlarged range of transmission rates, more spatial and temporal distribution differences, and more service transmission requests occurring in fast moving vehicles. In order to meet the requirements of B3G services, the B3G systems must have great improvement in network architecture, air interface scheme, radio resource allocation strategy, frequency bands, and Radio Frequency (RF) technology etc. Therefore, the research of the B3G systems should focus on the theory of generalized cellular communications networks, theory of the Multiple Input Multiple Output (MIMO) wireless transmission system, matching of radio resources to new-type air interfaces, new iterative detection and adaptive link methods, and new-type antenna and RF technologies.展开更多
BACKGROUND Patients with chronic hepatitis B(CHB)experience various problems,including low psychological flexibility,negative emotions,and poor sleep quality.Therefore,effective nursing interventions are required to r...BACKGROUND Patients with chronic hepatitis B(CHB)experience various problems,including low psychological flexibility,negative emotions,and poor sleep quality.Therefore,effective nursing interventions are required to reduce adverse events.Acceptance and commitment therapy(ACT)combined with enabling cognitivebehavioral education(ECBE)can improve patients'psychological and sleep.Therefore,we speculate that this may also be effective in patients with CHB.AIM To investigate the effects of different intervention methods on psychological flexibility,negative emotions,and sleep quality in patients with CHB.METHODS This retrospective study examined clinical and evaluation data of 129 patients with CHB.Intervention methods were divided into a conventional group(routine nursing,n=69)and a combination group(ACT combined with ECBE,n=60).We observed changes in psychological flexibility,negative emotions,sleep quality,and self-care ability in both groups.Observation items were evaluated using the Acceptance and Action Questionnaire-2nd Edition(AAQ-II),Self-Rating Anxiety Scale(SAS),Self-Rating Depression Scale(SDS),Pittsburgh Sleep Quality Index(PSQI),and Exercise of Self-Care Agency Scale(ESCA).RESULTS Compared with the conventional group,the AAQ-II score of the combined group was lower(F_(between-group effect)=8.548;F_(time effects)=25.020;F_(interaction effects)=52.930;all P<0.001),the SAS score(t=5.445)and SDS score(t=7.076)were lower(all P<0.001),as were the PSQI dimensions(tsleep quality=4.581,tfall sleep time=2.826,tsleep time=2.436,tsleep efficiency=5.787,tsleep disorder=5.008,thypnotic drugs=3.786,tdaytime dysfunction=4.812);all P<0.05).The ESCA scores for all dimensions were higher(thealth knowledge level=6.994,t self-concept=5.902,tself-responsibility=19.820,tself-care skills=8.470;all P<0.001).CONCLUSION ACT combined with ECBE in patients with CHB can improve psychological flexibility and sleep quality,alleviate negative emotions,and improve self-care.展开更多
现有蜂窝5G/B5G高可靠低时延通信(ultra-reliable and low latency communications,URLLC)标准3GPP Release 17-18采用经典正交频分复用(OFDM)多载波波形传输,因其工作在授权频带,较少考虑URLLCOFDM多载波传输抗干扰策略。未来工业物联...现有蜂窝5G/B5G高可靠低时延通信(ultra-reliable and low latency communications,URLLC)标准3GPP Release 17-18采用经典正交频分复用(OFDM)多载波波形传输,因其工作在授权频带,较少考虑URLLCOFDM多载波传输抗干扰策略。未来工业物联网异构多服务质量(quality of service,QoS)业务大部分部署于非授权频带,其无线通信链路变得复杂,现有URLLC-OFDM波形无法完全为工业物联网信息传输提供高可靠性、低时延的苛刻要求。首先,基于子载波可配置的OFDMA,将鲁棒性更高的子载波跳频(subcarrier frequency hopping,Sub-FH)技术应用于OFDMA中(即Sub-FH/OFDMA),以提高信号传输可靠性。然后,设计将Sub-FH/OFDMA波形融合到以微时隙为基本单位的调度策略中。该调度策略采用Hamming编码+微时隙结合的混合自动重传请求(HARQ)机制,有效降低端到端传输的重传次数,旨在提升节点传输的实时性。并推导了信息误码(块)率与重传次数的折中理论关系。仿真结果表明,在面对外部电磁干扰和内部多用户干扰时,该方案能够保障物联网节点的稳定传输质量,并在目标误块率为10-5时实现毫秒级短数据包的传输时延。通过波形设计和MAC时隙调度的跨层级设计,为未来B5G/6G通信在复杂工业物联网场景中的实际应用提供了可行解决方案。展开更多
文摘The evolution of global mobile data over the past decades in broadcasting, Internet of Things (IoT), education, healthcare, commerce, and energy has put strong pressure on 3G/4G mobile networks to improve their service offerings. These generations of mobile networks were initially invented to meet the requirements of the above-mentioned applications. However, as the requirements in these applications continue to increase, new mobile technologies such as 5G (fifth generation), 5G and beyond (B5G, beyond fifth generation), and 6G (sixth generation) are still progressing and being experimented. These networks are very heterogeneous generations of mobile networks that will have to offer very high throughput per user, good energy efficiency, better traffic capacity per area, improved spectral efficiency, very low latency, and high mobility. To meet these requirements, the radio interface of future mobile networks will have to be flexible and rationalized the available frequency resources. Therefore, new modulation methods, access techniques and waveforms capable of supporting these technological changes are proposed. This review presents brief descriptions of the types of 5G, B5G, and 6G waveforms. The 5G consists of OFDM including its transmission techniques: generalized frequency division multiplexing (GFDM), filter bank based multi-carrier (FBMC), universal filtered multi-carrier (UFMC), and index modulation (IM). Meanwhile, the 6G covers orthogonal time frequency space (OTFS), orthogonal chirp division multiplexing (OCDM) and orthogonal time sequence multiplexing (OTSM). The networks’ potentialities, advantages, disadvantages, and future directions are outlined.
文摘This study comprehensively reviews the literature to deeply explore the role of computer science and internet technologies in addressing educational inequality and socio-psychological issues,with a particular focus on applications of 5G,artificial intelligence(AI),and augmented/virtual reality(AR/VR).By analyzing how these technologies are reshaping learning and their potential to ameliorate educational disparities,the study reveals challenges present in ensuring educational equity.The research methodology includes exhaustive reviews of applications of AI and machine learning,the Internet of Things and wearable technologies integration,big data analytics and data mining,and the effects of online platforms and social media on socio-psychological issues.Besides,the study discusses applications of these technologies in educational inequality and socio-psychological problem-solving through the lens of 5G,AI,and AR/VR,while also delineating challenges faced by these emerging technologies and future outlooks.The study finds that while computer science and internet technologies hold promise to bridge academic divides and address socio-psychological problems,the complexity of technology access and infrastructure,lack of digital literacy and skills,and critical ethical and privacy issues can impact widespread adoption and efficacy.Overall,the study provides a novel perspective to understand the potential of computer science and internet technologies in ameliorating educational inequality and socio-psychological issues,while pointing to new directions for future research.It also emphasizes the importance of cooperation among educational institutions,technology vendors,policymakers and researchers,and establishing comprehensive ethical guidelines and regulations to ensure the responsible use of these technologies.
基金funded by The National Natural Science Foundation of China under Grant(No.62273108,62306081)The Youth Project of Guangdong Artificial Intelligence and Digital Economy Laboratory(Guangzhou)(PZL2022KF0006)+3 种基金The National Key Research and Development Program of China(2022YFB3604502)Special Fund Project of GuangzhouScience and Technology Innovation Development(202201011307)Guangdong Province Industrial Internet Identity Analysis and Construction Guidance Fund Secondary Node Project(1746312)Special Projects in Key Fields of General Colleges and Universities in Guangdong Province(2021ZDZX1016).
文摘Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of B5G.The multiwatermarking process employs spread transform dither modulation.During the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading vectors.Consequently,multiple watermarks can be simultaneously embedded into the same position of a multimedia signal.Moreover,the multiple watermarks can be extracted without affecting one another during the extraction process.We analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility.
基金supported in part by National Natural Science Foundation of China under Grant Nos.61971029 and U22B2004in part by Beijing Municipal Natural Science Foundation under Grant No.L222002.
文摘Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so that the communication distance is short.In this paper,we first calculate the communication distance upper bounds for both uplink and downlink by measuring the tag sensitivity and reflection coefficient.It is found that the activation voltage of the envelope detection diode of the downlink tag is the main factor limiting the back-scatter communication distance.Based on this analysis,we then propose to implement a low-noise amplifier(LNA)module before the envelope detection at the tag to enhance the incident signal strength.Our experimental results on the hardware platform show that our method can increase the downlink communication range by nearly 20 m.
基金This work was supported in part by the National Science Fund for Distinguished Young Scholars in China under grant 61425012the National Science Foundation Project in China under grant 61931005 and 61731017.
文摘Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in construction.This paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within 6G.Based on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.
基金supported by the Korea Foundation for Advanced Studies and Asia Research Center of Nankai University(Grant No.AS0719)
文摘On the basis of analyzing both domestic and foreign evaluation systems for the e-government and also taking into account of the current situation of government portals in urban centers,the paper is aimed to construct an evaluation system primarily for the measurement of the service capability of business-oriented G2B portals of local governments in general and those G2B portals of the new development zones in particular.This system is composed of 6 first tier indicators,18 second tier indicators and 90 third tier indicators.And the weight of each indicator is determined by Delphi Method and Analytic Hierarchy Process(AHP) Method.Subsequently,we used this system to evaluate the government portals of Tianjin Binhai New Area and Shanghai Pudong New Area and proved to have the desired practicability.
基金Program ofNational Nature Science Foundation of China(No. 60496311) Project of National "863"Plan ofChina (No. 2005AA121052)
文摘Compared with the services in 3G, services in Beyond 3G (B3G) have some distinctive characteristics such as the packet data services being the majority, more service types, larger scale of services, higher peak transmission rate, enlarged range of transmission rates, more spatial and temporal distribution differences, and more service transmission requests occurring in fast moving vehicles. In order to meet the requirements of B3G services, the B3G systems must have great improvement in network architecture, air interface scheme, radio resource allocation strategy, frequency bands, and Radio Frequency (RF) technology etc. Therefore, the research of the B3G systems should focus on the theory of generalized cellular communications networks, theory of the Multiple Input Multiple Output (MIMO) wireless transmission system, matching of radio resources to new-type air interfaces, new iterative detection and adaptive link methods, and new-type antenna and RF technologies.
文摘BACKGROUND Patients with chronic hepatitis B(CHB)experience various problems,including low psychological flexibility,negative emotions,and poor sleep quality.Therefore,effective nursing interventions are required to reduce adverse events.Acceptance and commitment therapy(ACT)combined with enabling cognitivebehavioral education(ECBE)can improve patients'psychological and sleep.Therefore,we speculate that this may also be effective in patients with CHB.AIM To investigate the effects of different intervention methods on psychological flexibility,negative emotions,and sleep quality in patients with CHB.METHODS This retrospective study examined clinical and evaluation data of 129 patients with CHB.Intervention methods were divided into a conventional group(routine nursing,n=69)and a combination group(ACT combined with ECBE,n=60).We observed changes in psychological flexibility,negative emotions,sleep quality,and self-care ability in both groups.Observation items were evaluated using the Acceptance and Action Questionnaire-2nd Edition(AAQ-II),Self-Rating Anxiety Scale(SAS),Self-Rating Depression Scale(SDS),Pittsburgh Sleep Quality Index(PSQI),and Exercise of Self-Care Agency Scale(ESCA).RESULTS Compared with the conventional group,the AAQ-II score of the combined group was lower(F_(between-group effect)=8.548;F_(time effects)=25.020;F_(interaction effects)=52.930;all P<0.001),the SAS score(t=5.445)and SDS score(t=7.076)were lower(all P<0.001),as were the PSQI dimensions(tsleep quality=4.581,tfall sleep time=2.826,tsleep time=2.436,tsleep efficiency=5.787,tsleep disorder=5.008,thypnotic drugs=3.786,tdaytime dysfunction=4.812);all P<0.05).The ESCA scores for all dimensions were higher(thealth knowledge level=6.994,t self-concept=5.902,tself-responsibility=19.820,tself-care skills=8.470;all P<0.001).CONCLUSION ACT combined with ECBE in patients with CHB can improve psychological flexibility and sleep quality,alleviate negative emotions,and improve self-care.
文摘现有蜂窝5G/B5G高可靠低时延通信(ultra-reliable and low latency communications,URLLC)标准3GPP Release 17-18采用经典正交频分复用(OFDM)多载波波形传输,因其工作在授权频带,较少考虑URLLCOFDM多载波传输抗干扰策略。未来工业物联网异构多服务质量(quality of service,QoS)业务大部分部署于非授权频带,其无线通信链路变得复杂,现有URLLC-OFDM波形无法完全为工业物联网信息传输提供高可靠性、低时延的苛刻要求。首先,基于子载波可配置的OFDMA,将鲁棒性更高的子载波跳频(subcarrier frequency hopping,Sub-FH)技术应用于OFDMA中(即Sub-FH/OFDMA),以提高信号传输可靠性。然后,设计将Sub-FH/OFDMA波形融合到以微时隙为基本单位的调度策略中。该调度策略采用Hamming编码+微时隙结合的混合自动重传请求(HARQ)机制,有效降低端到端传输的重传次数,旨在提升节点传输的实时性。并推导了信息误码(块)率与重传次数的折中理论关系。仿真结果表明,在面对外部电磁干扰和内部多用户干扰时,该方案能够保障物联网节点的稳定传输质量,并在目标误块率为10-5时实现毫秒级短数据包的传输时延。通过波形设计和MAC时隙调度的跨层级设计,为未来B5G/6G通信在复杂工业物联网场景中的实际应用提供了可行解决方案。