首页 > 最新文献

IEEE Transactions on Green Communications and Networking最新文献

英文 中文
Energy- and Reliability-Aware Provisioning of Parallelized Service Function Chains With Delay Guarantees 具有延迟保证的并行化服务功能链的能量和可靠性感知供应
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-22 DOI: 10.1109/TGCN.2023.3317927
Venkatarami Reddy Chintapalli;Balaprakasa Rao Killi;Rajat Partani;Bheemarjuna Reddy Tamma;C. Siva Ram Murthy
Network Functions Virtualization (NFV) leverages virtualization and cloud computing technologies to make networks more flexible, manageable, and scalable. Instead of using traditional hardware middleboxes, NFV uses more flexible Virtual Network Functions (VNFs) running on commodity servers. One of the key challenges in NFV is to ensure strict reliability and low latency while also improving energy efficiency. Any software or hardware failures in an NFV environment can disrupt the service provided by a chain of VNFs, known as a Service Function Chain (SFC), resulting in significant data loss, delays, and wasted resources. Due to the sequential nature of SFC, latency increases linearly with the number of VNFs. To address this issue, researchers have proposed parallelized SFC or VNF parallelization, which allows multiple independent VNFs in an SFC to run in parallel. In this work, we propose a method to solve the parallelized SFC deployment problem as an Integer Linear Program (ILP) that minimizes energy consumption while ensuring reliability and delay constraints. Since the problem is NP-hard, we also propose a heuristic scheme named ERASE that determines the placement of VNFs and routes traffic through them in a way that minimizes energy consumption while meeting capacity, reliability, and delay requirements. The effectiveness of ERASE is evaluated through extensive simulations and it is shown to perform better than benchmark schemes in terms of total energy consumption and reliability achieved.
网络功能虚拟化(NFV)利用虚拟化和云计算技术,使网络更具灵活性、可管理性和可扩展性。NFV 不使用传统的硬件中间件,而是使用在商品服务器上运行的更灵活的虚拟网络功能(VNF)。NFV 的主要挑战之一是确保严格的可靠性和低延迟,同时提高能效。在 NFV 环境中,任何软件或硬件故障都可能中断由一连串 VNF(称为服务功能链 (SFC))提供的服务,导致严重的数据丢失、延迟和资源浪费。由于 SFC 的顺序性,延迟会随着 VNF 数量的增加而线性增加。为解决这一问题,研究人员提出了并行化 SFC 或 VNF 并行化方案,允许并行运行 SFC 中的多个独立 VNF。在这项工作中,我们提出了一种将并行化 SFC 部署问题作为整数线性规划 (ILP) 来解决的方法,该方法能在确保可靠性和延迟约束的同时最大限度地降低能耗。由于该问题具有 NP 难度,我们还提出了一种名为 ERASE 的启发式方案,该方案可确定 VNF 的位置,并以能耗最小同时满足容量、可靠性和延迟要求的方式路由流量。我们通过大量仿真对 ERASE 的有效性进行了评估,结果表明它在总能耗和可靠性方面的表现优于基准方案。
{"title":"Energy- and Reliability-Aware Provisioning of Parallelized Service Function Chains With Delay Guarantees","authors":"Venkatarami Reddy Chintapalli;Balaprakasa Rao Killi;Rajat Partani;Bheemarjuna Reddy Tamma;C. Siva Ram Murthy","doi":"10.1109/TGCN.2023.3317927","DOIUrl":"10.1109/TGCN.2023.3317927","url":null,"abstract":"Network Functions Virtualization (NFV) leverages virtualization and cloud computing technologies to make networks more flexible, manageable, and scalable. Instead of using traditional hardware middleboxes, NFV uses more flexible Virtual Network Functions (VNFs) running on commodity servers. One of the key challenges in NFV is to ensure strict reliability and low latency while also improving energy efficiency. Any software or hardware failures in an NFV environment can disrupt the service provided by a chain of VNFs, known as a Service Function Chain (SFC), resulting in significant data loss, delays, and wasted resources. Due to the sequential nature of SFC, latency increases linearly with the number of VNFs. To address this issue, researchers have proposed parallelized SFC or VNF parallelization, which allows multiple independent VNFs in an SFC to run in parallel. In this work, we propose a method to solve the parallelized SFC deployment problem as an Integer Linear Program (ILP) that minimizes energy consumption while ensuring reliability and delay constraints. Since the problem is NP-hard, we also propose a heuristic scheme named ERASE that determines the placement of VNFs and routes traffic through them in a way that minimizes energy consumption while meeting capacity, reliability, and delay requirements. The effectiveness of ERASE is evaluated through extensive simulations and it is shown to perform better than benchmark schemes in terms of total energy consumption and reliability achieved.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135599196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Channel Estimation via Subcarrier Grouping for Wideband mmWave Hybrid Massive MIMO-OFDM Systems 宽带毫米波混合大规模 MIMO-OFDM 系统的子载波分组信道估计
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-22 DOI: 10.1109/TGCN.2023.3317829
Yang Li;Anzhong Hu
This paper studies the channel estimation of millimeter-wave massive multiple-input multiple-output orthogonal frequency division multiplexing systems with a wide bandwidth and a hybrid structure. By considering the influence of the frequency-spatial wideband effect and the channel sparsity, the subcarriers are grouped, the support as well as the angle of each group are estimated. Based on the angle estimate, the support of each subcarrier is deduced. The computational complexities are analyzed and compared, which show the proposed method has a lower computational complexity. The Cramér-Rao bound (CRB) and the spectral efficiency are also analyzed. The analysis shows that the spectral efficiency increases logarithmly with the increase of the signal-to-noise ratio when channel estimation is perfect but is limited otherwise. The simulations show the proposed method gets closer to the CRB in channel estimation error and achieves higher spectral efficiency than the existing one.
本文研究了具有宽带宽和混合结构的毫米波大规模多输入多输出正交频分复用系统的信道估计。通过考虑频空宽带效应和信道稀疏性的影响,对子载波进行分组,并估计每个分组的支持度和角度。根据角度估计值,推导出每个子载波的支持度。对计算复杂度进行了分析和比较,结果表明所提出的方法具有更低的计算复杂度。此外,还分析了克拉梅尔-拉奥约束(CRB)和频谱效率。分析表明,当信道估计完美时,频谱效率随信噪比的增加呈对数增长,反之则有限。模拟结果表明,与现有方法相比,拟议方法的信道估计误差更接近 CRB,频谱效率更高。
{"title":"Channel Estimation via Subcarrier Grouping for Wideband mmWave Hybrid Massive MIMO-OFDM Systems","authors":"Yang Li;Anzhong Hu","doi":"10.1109/TGCN.2023.3317829","DOIUrl":"10.1109/TGCN.2023.3317829","url":null,"abstract":"This paper studies the channel estimation of millimeter-wave massive multiple-input multiple-output orthogonal frequency division multiplexing systems with a wide bandwidth and a hybrid structure. By considering the influence of the frequency-spatial wideband effect and the channel sparsity, the subcarriers are grouped, the support as well as the angle of each group are estimated. Based on the angle estimate, the support of each subcarrier is deduced. The computational complexities are analyzed and compared, which show the proposed method has a lower computational complexity. The Cramér-Rao bound (CRB) and the spectral efficiency are also analyzed. The analysis shows that the spectral efficiency increases logarithmly with the increase of the signal-to-noise ratio when channel estimation is perfect but is limited otherwise. The simulations show the proposed method gets closer to the CRB in channel estimation error and achieves higher spectral efficiency than the existing one.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135599187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Fractional Programming-Based Uplink Transmission Power Allocation for User-Centric Cell-Free Massive MIMO Systems 基于分数编程的上行链路传输功率分配,适用于以用户为中心的无小区大规模多输入多输出系统
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-20 DOI: 10.1109/TGCN.2023.3317674
Manobendu Sarker;Abraham O. Fapojuwo
In this paper, two centralized power allocation schemes are proposed for data transmission during the uplink phase in the user-centric cell-free (CF) massive multiple-input multiple-output (mMIMO) systems. The proposed schemes solve two non-convex power allocation problems of maximizing the summation of spectral efficiency (SE) (max-sum-SE) and that of maximizing the minimum SE (max-min-SE) to improve the overall SE and fairness performance while simultaneously reducing the per-user equipment (UE) transmission power. To solve the max-sum-SE problem, we utilize the fractional programming (FP) method to transform the non-convex problem into a series of convex problems. Furthermore, the max-min-SE problem is solved after reformulating it with the help of the FP method along with the alternating direction method of multipliers (ADMM) technique. The proposed schemes are computationally efficient as they solve the aforementioned problems iteratively by using only closed-form updates for the decision variables, which is one of their strongest features, and suitable for allocating power in large-scale CF mMIMO systems. Numerical results demonstrate that, compared to the no power control scheme, the proposed schemes improve the average SE performance by up to 47% while reducing the average transmission power by up to 95%.
本文针对以用户为中心的无小区(CF)大规模多输入多输出(mMIMO)系统中上行链路阶段的数据传输,提出了两种集中式功率分配方案。所提方案解决了两个非凸功率分配问题,即频谱效率(SE)求和最大化(max-sum-SE)和频谱效率(SE)最小化(max-min-SE)最大化问题,以提高整体频谱效率和公平性,同时降低每用户设备(UE)的传输功率。为了解决最大总和-SE 问题,我们利用分数编程(FP)方法将非凸问题转化为一系列凸问题。此外,在 FP 方法和交替乘法(ADMM)技术的帮助下,最大-最小-SE 问题也得到了解决。所提出的方案计算效率高,因为它们只使用决策变量的闭式更新来迭代解决上述问题,这是其最大的特点之一,适用于大规模 CF mMIMO 系统中的功率分配。数值结果表明,与无功率控制方案相比,所提出的方案可将平均 SE 性能提高 47%,同时将平均传输功率降低 95%。
{"title":"Fractional Programming-Based Uplink Transmission Power Allocation for User-Centric Cell-Free Massive MIMO Systems","authors":"Manobendu Sarker;Abraham O. Fapojuwo","doi":"10.1109/TGCN.2023.3317674","DOIUrl":"10.1109/TGCN.2023.3317674","url":null,"abstract":"In this paper, two centralized power allocation schemes are proposed for data transmission during the uplink phase in the user-centric cell-free (CF) massive multiple-input multiple-output (mMIMO) systems. The proposed schemes solve two non-convex power allocation problems of maximizing the summation of spectral efficiency (SE) (max-sum-SE) and that of maximizing the minimum SE (max-min-SE) to improve the overall SE and fairness performance while simultaneously reducing the per-user equipment (UE) transmission power. To solve the max-sum-SE problem, we utilize the fractional programming (FP) method to transform the non-convex problem into a series of convex problems. Furthermore, the max-min-SE problem is solved after reformulating it with the help of the FP method along with the alternating direction method of multipliers (ADMM) technique. The proposed schemes are computationally efficient as they solve the aforementioned problems iteratively by using only closed-form updates for the decision variables, which is one of their strongest features, and suitable for allocating power in large-scale CF mMIMO systems. Numerical results demonstrate that, compared to the no power control scheme, the proposed schemes improve the average SE performance by up to 47% while reducing the average transmission power by up to 95%.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135557446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Latency-Aware Radio Resource Optimization in Learning-Based Cloud-Aided Small Cell Wireless Networks 基于学习的云辅助小蜂窝无线网络中的延迟感知无线电资源优化
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-19 DOI: 10.1109/TGCN.2023.3317128
Syed Tamoor-ul-Hassan;Sumudu Samarakoon;Mehdi Bennis;Matti Latva-aho
Low latency communication is one of the fundamental requirements for 5G wireless networks and beyond. In this paper, a novel approach for joint caching, user scheduling and resource allocation is proposed for minimizing the queuing latency in serving users’ requests in cloud-aided wireless networks. Due to the slow temporal variations in user requests, a time-scale separation technique is used to decouple the joint caching problem from user scheduling and radio resource allocation problems. To serve the spatio-temporal user requests under storage limitations, a Reinforcement Learning (RL) approach is used to optimize the caching strategy at the small cell base stations by minimizing the content fetching cost. A spectral clustering algorithm is proposed to speed-up the convergence of the RL algorithm for a large content caching problem by clustering contents based on user requests. Meanwhile, a dynamic mechanism is proposed to locally group coupled base stations based on user requests to collaboratively optimize the caching strategies. To further improve the latency in fetching and serving user requests, a dynamic matching algorithm is proposed to schedule users and to allocate users to radio resources based on user requests and queue lengths under probabilistic latency constraints. Simulation results show the proposed approach significantly reduces the average delay from 21% to 90% compared to random caching strategy, random resource allocation and random scheduling baselines.
低延迟通信是 5G 无线网络及其他网络的基本要求之一。本文提出了一种联合缓存、用户调度和资源分配的新方法,以最小化云辅助无线网络中服务用户请求的排队延迟。由于用户请求的时间变化较慢,因此采用了时间尺度分离技术,将联合缓存问题与用户调度和无线资源分配问题解耦。为了在存储限制条件下满足用户的时空请求,采用了强化学习(RL)方法,通过最小化内容获取成本来优化小基站的缓存策略。针对大型内容缓存问题,提出了一种光谱聚类算法,通过根据用户请求对内容进行聚类来加快 RL 算法的收敛速度。同时,还提出了一种动态机制,根据用户请求对耦合基站进行本地分组,以协同优化缓存策略。为进一步改善获取和服务用户请求的延迟,提出了一种动态匹配算法,在概率延迟约束条件下,根据用户请求和队列长度调度用户并将用户分配到无线电资源。仿真结果表明,与随机缓存策略、随机资源分配和随机调度基线相比,所提出的方法将平均延迟从 21% 显著降低到 90%。
{"title":"Latency-Aware Radio Resource Optimization in Learning-Based Cloud-Aided Small Cell Wireless Networks","authors":"Syed Tamoor-ul-Hassan;Sumudu Samarakoon;Mehdi Bennis;Matti Latva-aho","doi":"10.1109/TGCN.2023.3317128","DOIUrl":"10.1109/TGCN.2023.3317128","url":null,"abstract":"Low latency communication is one of the fundamental requirements for 5G wireless networks and beyond. In this paper, a novel approach for joint caching, user scheduling and resource allocation is proposed for minimizing the queuing latency in serving users’ requests in cloud-aided wireless networks. Due to the slow temporal variations in user requests, a time-scale separation technique is used to decouple the joint caching problem from user scheduling and radio resource allocation problems. To serve the spatio-temporal user requests under storage limitations, a Reinforcement Learning (RL) approach is used to optimize the caching strategy at the small cell base stations by minimizing the content fetching cost. A spectral clustering algorithm is proposed to speed-up the convergence of the RL algorithm for a large content caching problem by clustering contents based on user requests. Meanwhile, a dynamic mechanism is proposed to locally group coupled base stations based on user requests to collaboratively optimize the caching strategies. To further improve the latency in fetching and serving user requests, a dynamic matching algorithm is proposed to schedule users and to allocate users to radio resources based on user requests and queue lengths under probabilistic latency constraints. Simulation results show the proposed approach significantly reduces the average delay from 21% to 90% compared to random caching strategy, random resource allocation and random scheduling baselines.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135555673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Spatial Scattering Modulation With Multipath Component Aggregation 空间散射调制与多径分量聚合
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-14 DOI: 10.1109/TGCN.2023.3315247
Jiliang Zhang;Wei Liu;Alan Tennant;Weijie Qi;Jiming Chen;Jie Zhang
In this paper, a multipath component aggregation (MCA) mechanism is introduced for spatial scattering modulation (SSM) to overcome the limitation in conventional SSM that the transmit antenna array steers the beam to a single multipath (MP) component at each instance. In the proposed MCA-SSM system, information bits are divided into two streams. One is mapped to an amplitude-phase-modulation (APM) constellation symbol, and the other is mapped to a beam vector symbol which steers multiple beams to selected strongest MP components via an MCA matrix. In comparison with the conventional SSM system, the proposed MCA-SSM enhances the bit error performance by avoiding both low receiving power due to steering the beam to a single weak MP component and inter-MP interference due to MP components with close values of angle of arrival (AoA) or angle of departure (AoD). For the proposed MCA-SSM, a union upper bound (UUB) on the average bit error probability (ABEP) with any MCA matrix is analytically derived and validated via Monte Carlo simulations. Based on the UUB, the MCA matrix is analytically optimized to minimize the ABEP of the MCA-SSM. Finally, numerical experiments are carried out, which show that the proposed MCA-SSM system remarkably outperforms the state-of-the-art SSM system in terms of ABEP under a typical indoor environment.
本文为空间散射调制(SSM)引入了一种多径分量聚合(MCA)机制,以克服传统 SSM 中发射天线阵列每次都将波束导向单一多径(MP)分量的限制。在拟议的 MCA-SSM 系统中,信息比特被分为两个流。一个映射到振幅相位调制(APM)星座符号,另一个映射到波束矢量符号,后者通过 MCA 矩阵将多个波束导向选定的最强 MP 分量。与传统的 SSM 系统相比,拟议的 MCA-SSM 可避免因将波束导向单个弱 MP 分量而导致的低接收功率,以及因到达角(AoA)或离去角(AoD)值接近的 MP 分量而导致的 MP 间干扰,从而提高误码率性能。对于所提出的 MCA-SSM,分析得出了任何 MCA 矩阵的平均比特误差概率 (ABEP) 的联合上界 (UUB),并通过蒙特卡罗模拟进行了验证。根据 UUB,对 MCA 矩阵进行分析优化,以最小化 MCA-SSM 的 ABEP。最后,进行了数值实验,结果表明,在典型的室内环境下,所提出的 MCA-SSM 系统在 ABEP 方面明显优于最先进的 SSM 系统。
{"title":"Spatial Scattering Modulation With Multipath Component Aggregation","authors":"Jiliang Zhang;Wei Liu;Alan Tennant;Weijie Qi;Jiming Chen;Jie Zhang","doi":"10.1109/TGCN.2023.3315247","DOIUrl":"10.1109/TGCN.2023.3315247","url":null,"abstract":"In this paper, a multipath component aggregation (MCA) mechanism is introduced for spatial scattering modulation (SSM) to overcome the limitation in conventional SSM that the transmit antenna array steers the beam to a single multipath (MP) component at each instance. In the proposed MCA-SSM system, information bits are divided into two streams. One is mapped to an amplitude-phase-modulation (APM) constellation symbol, and the other is mapped to a beam vector symbol which steers multiple beams to selected strongest MP components via an MCA matrix. In comparison with the conventional SSM system, the proposed MCA-SSM enhances the bit error performance by avoiding both low receiving power due to steering the beam to a single weak MP component and inter-MP interference due to MP components with close values of angle of arrival (AoA) or angle of departure (AoD). For the proposed MCA-SSM, a union upper bound (UUB) on the average bit error probability (ABEP) with any MCA matrix is analytically derived and validated via Monte Carlo simulations. Based on the UUB, the MCA matrix is analytically optimized to minimize the ABEP of the MCA-SSM. Finally, numerical experiments are carried out, which show that the proposed MCA-SSM system remarkably outperforms the state-of-the-art SSM system in terms of ABEP under a typical indoor environment.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135443290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Spatial Modulation With Energy Detection: Diversity Analysis and Experimental Evaluation 带能量检测的空间调制:多样性分析与实验评估
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-13 DOI: 10.1109/TGCN.2023.3314870
Elio Faddoul;Ghassan M. Kraidy;Constantinos Psomas;Symeon Chatzinotas;Ioannis Krikidis
In this paper, we present a non-coherent energy detection scheme for spatial modulation (SM) systems. In particular, the use of SM is motivated by its low-complexity implementation in comparison to multiple-input multiple-output (MIMO) systems, achieved through the activation of a single antenna during transmission. Moreover, energy detection-based communications restrict the channel state information to the magnitude of the fading gains. This consideration makes the design applicable for low-cost low-powered devices since phase estimation and its associated circuitry are avoided. We derive an energy detection metric for a multi-antenna receiver based on the maximum-likelihood (ML) criterion. By considering a biased pulse amplitude modulation, we develop an analytical framework for the SM symbol error rate at high signal-to-noise ratios. Numerical results show that the diversity order is proportional to half the number of receive antennas; this result stems from having partial receiver channel knowledge. In addition, we compare the performance of the proposed scheme with that of the coherent ML receiver and show that the SM energy detector outperforms its coherent counterpart in certain scenarios, particularly when utilizing non-negative constellations. Ultimately, we implement an SM testbed using software-defined radio devices and provide experimental error rate measurements that validate our theoretical contribution.
本文针对空间调制(SM)系统提出了一种非相干能量检测方案。与多输入多输出(MIMO)系统相比,空间调制(SM)系统的实施复杂度较低,在传输过程中只需激活一根天线即可实现。此外,基于能量检测的通信将信道状态信息限制为衰减增益的大小。由于避免了相位估计及其相关电路,这种设计适用于低成本、低功率设备。我们基于最大似然(ML)准则,为多天线接收器推导出一种能量检测指标。通过考虑偏置脉冲幅度调制,我们为高信噪比条件下的 SM 符号错误率建立了一个分析框架。数值结果表明,分集阶与接收天线数量的一半成正比;这一结果源于部分接收器信道知识。此外,我们还将所提方案的性能与相干 ML 接收器的性能进行了比较,结果表明 SM 能量检测器在某些情况下的性能优于相干接收器,尤其是在使用非负星座时。最后,我们利用软件定义无线电设备实现了 SM 测试平台,并提供了实验误差率测量结果,验证了我们的理论贡献。
{"title":"Spatial Modulation With Energy Detection: Diversity Analysis and Experimental Evaluation","authors":"Elio Faddoul;Ghassan M. Kraidy;Constantinos Psomas;Symeon Chatzinotas;Ioannis Krikidis","doi":"10.1109/TGCN.2023.3314870","DOIUrl":"10.1109/TGCN.2023.3314870","url":null,"abstract":"In this paper, we present a non-coherent energy detection scheme for spatial modulation (SM) systems. In particular, the use of SM is motivated by its low-complexity implementation in comparison to multiple-input multiple-output (MIMO) systems, achieved through the activation of a single antenna during transmission. Moreover, energy detection-based communications restrict the channel state information to the magnitude of the fading gains. This consideration makes the design applicable for low-cost low-powered devices since phase estimation and its associated circuitry are avoided. We derive an energy detection metric for a multi-antenna receiver based on the maximum-likelihood (ML) criterion. By considering a biased pulse amplitude modulation, we develop an analytical framework for the SM symbol error rate at high signal-to-noise ratios. Numerical results show that the diversity order is proportional to half the number of receive antennas; this result stems from having partial receiver channel knowledge. In addition, we compare the performance of the proposed scheme with that of the coherent ML receiver and show that the SM energy detector outperforms its coherent counterpart in certain scenarios, particularly when utilizing non-negative constellations. Ultimately, we implement an SM testbed using software-defined radio devices and provide experimental error rate measurements that validate our theoretical contribution.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135403386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
NR DCP: An Enhanced Power Saving Mechanism With Wake-Up Signal Enabled DRX NR DCP:支持唤醒信号的 DRX 增强省电机制
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-07 DOI: 10.1109/TGCN.2023.3312707
He-Hsuan Liu;Kuang-Hsun Lin;Hung-Yu Wei
The Discontinuous Reception (DRX) mechanism is designed by the Third Generation Partnership Project (3GPP) for power saving in the Long-Term Evolution and the New Radio technologies. In Release 16, 3GPP designed an advanced signal called Downlink Control Information of Power Saving (DCP). Energy-critical devices can conserve more energy by turning off the receiving module for a long period according to the DCP indication from the next-generation base station (gNB). However, the possible failure of DCP potentially causes extra power consumption or packet loss. To handle the problem, 3GPP allows the gNB to configure the default behavior when the DCP is not detected. In this paper, we accurately model the two DCP mechanisms with different default settings with a three-state discrete-time Markov model. Moreover, we also propose a method that efficiently finds a proper parameter configuration under latency and reliability constraints. Through simulation, we validate the accuracy of the model. In addition, we conduct another simulation to show that the proposed method finds a parameter set yielding near-optimal performance within a short execution time. The derived model, along with the proposed parameter setting method, serves as a solid basis for future research on power saving and sustainability.
不连续接收(DRX)机制由第三代合作伙伴计划(3GPP)设计,用于在长期演进和新无线电技术中节省功耗。在第 16 版中,3GPP 设计了一种名为 "下行链路节电控制信息"(DCP)的高级信号。能源关键型设备可根据下一代基站(gNB)的 DCP 指示长期关闭接收模块,从而节省更多能源。然而,DCP 可能出现的故障会导致额外的功耗或数据包丢失。为了解决这个问题,3GPP 允许 gNB 配置未检测到 DCP 时的默认行为。在本文中,我们用一个三态离散时间马尔可夫模型精确地模拟了具有不同默认设置的两种 DCP 机制。此外,我们还提出了一种方法,能在延迟和可靠性约束条件下有效地找到合适的参数配置。通过仿真,我们验证了模型的准确性。此外,我们还进行了另一次仿真,证明所提出的方法能在较短的执行时间内找到接近最佳性能的参数集。推导出的模型和建议的参数设置方法为未来的节能和可持续性研究奠定了坚实的基础。
{"title":"NR DCP: An Enhanced Power Saving Mechanism With Wake-Up Signal Enabled DRX","authors":"He-Hsuan Liu;Kuang-Hsun Lin;Hung-Yu Wei","doi":"10.1109/TGCN.2023.3312707","DOIUrl":"10.1109/TGCN.2023.3312707","url":null,"abstract":"The Discontinuous Reception (DRX) mechanism is designed by the Third Generation Partnership Project (3GPP) for power saving in the Long-Term Evolution and the New Radio technologies. In Release 16, 3GPP designed an advanced signal called Downlink Control Information of Power Saving (DCP). Energy-critical devices can conserve more energy by turning off the receiving module for a long period according to the DCP indication from the next-generation base station (gNB). However, the possible failure of DCP potentially causes extra power consumption or packet loss. To handle the problem, 3GPP allows the gNB to configure the default behavior when the DCP is not detected. In this paper, we accurately model the two DCP mechanisms with different default settings with a three-state discrete-time Markov model. Moreover, we also propose a method that efficiently finds a proper parameter configuration under latency and reliability constraints. Through simulation, we validate the accuracy of the model. In addition, we conduct another simulation to show that the proposed method finds a parameter set yielding near-optimal performance within a short execution time. The derived model, along with the proposed parameter setting method, serves as a solid basis for future research on power saving and sustainability.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"62571503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Optimizing Sample Delivery in RF-Charging Multi-Hop IoT Networks 优化射频充电多跳物联网网络中的样本传输
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-09-04 DOI: 10.1109/TGCN.2023.3311590
Muchen Jiang;Kwan-Wu Chin
This paper studies sample delivery in a multi-hop network where a power beacon charges devices via radio frequency (RF) signals. Devices forward samples with a deadline from a source to a sink. The goal is to minimize the power beacon’s transmit power and guarantee that samples arrive at the sink with probability $(1-epsilon)$ by their deadline, where $epsilon $ is a given probability of failure. A key challenge is that the power beacon does not have instantaneous channel gains information to devices and also between devices; i.e., it does not know the energy level of devices. To this end, we formulate a chance-constrained stochastic program for the problem at hand, and employ the sample-average approximation (SAA) method to compute a solution. We also outline two novel approximation methods: Sampling based Probabilistic Optimal Power Allocation (S-POPA) and Bayesian Optimization based Probabilistic Optimal Power Allocation (BO-POPA). Briefly, S-POPA generates a set of candidate solutions and iteratively learns the solution that returns a high probability of success. On the other hand, BO-POPA applies the Bayesian optimization framework to construct a surrogate model to predict the reward value of transmit power allocations. Numerical results show that the performance of S-POPA and BO-POPA achieves on average 86.91% and 79.25% of the transmit power computed by SAA.
本文研究了多跳网络中的样本传输问题,在该网络中,功率信标通过射频(RF)信号为设备充电。设备在截止日期前将样本从源发送到汇。目标是最大限度地降低功率信标的发射功率,并保证样本在截止日期前以 $(1-epsilon)$ 的概率到达汇,其中 $epsilon $ 是给定的失败概率。一个关键的挑战是,功率信标并不掌握设备与设备之间的瞬时信道增益信息;也就是说,它不知道设备的能量水平。为此,我们为当前问题制定了一个机会受限随机程序,并采用样本平均近似(SAA)方法来计算解决方案。我们还概述了两种新型近似方法:基于采样的概率最优功率分配 (S-POPA) 和基于贝叶斯优化的概率最优功率分配 (BO-POPA)。简而言之,S-POPA 生成一组候选解决方案,并迭代学习返回高成功概率的解决方案。另一方面,BO-POPA 应用贝叶斯优化框架来构建一个代理模型,以预测发射功率分配的奖励值。数值结果表明,S-POPA 和 BO-POPA 的性能平均达到 SAA 计算的发射功率的 86.91% 和 79.25%。
{"title":"Optimizing Sample Delivery in RF-Charging Multi-Hop IoT Networks","authors":"Muchen Jiang;Kwan-Wu Chin","doi":"10.1109/TGCN.2023.3311590","DOIUrl":"10.1109/TGCN.2023.3311590","url":null,"abstract":"This paper studies sample delivery in a multi-hop network where a power beacon charges devices via radio frequency (RF) signals. Devices forward samples with a deadline from a source to a sink. The goal is to minimize the power beacon’s transmit power and guarantee that samples arrive at the sink with probability \u0000<inline-formula> <tex-math>$(1-epsilon)$ </tex-math></inline-formula>\u0000 by their deadline, where \u0000<inline-formula> <tex-math>$epsilon $ </tex-math></inline-formula>\u0000 is a given probability of failure. A key challenge is that the power beacon does not have instantaneous channel gains information to devices and also between devices; i.e., it does not know the energy level of devices. To this end, we formulate a chance-constrained stochastic program for the problem at hand, and employ the sample-average approximation (SAA) method to compute a solution. We also outline two novel approximation methods: Sampling based Probabilistic Optimal Power Allocation (S-POPA) and Bayesian Optimization based Probabilistic Optimal Power Allocation (BO-POPA). Briefly, S-POPA generates a set of candidate solutions and iteratively learns the solution that returns a high probability of success. On the other hand, BO-POPA applies the Bayesian optimization framework to construct a surrogate model to predict the reward value of transmit power allocations. Numerical results show that the performance of S-POPA and BO-POPA achieves on average 86.91% and 79.25% of the transmit power computed by SAA.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"62571491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Federated Learning With Energy Harvesting Devices 利用能量收集设备进行联合学习
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-08-31 DOI: 10.1109/TGCN.2023.3310569
Li Zeng;Dingzhu Wen;Guangxu Zhu;Changsheng You;Qimei Chen;Yuanming Shi
Federated learning (FL) is a promising technique for distilling artificial intelligence from massive data distributed in Internet-of-Things networks, while keeping data privacy. However, the efficient deployment of FL faces several challenges due to, e.g., limited radio resources, computation capabilities, and battery lives of Internet-of-Things devices. To address these challenges, in this work, the energy harvesting technique is first enabled on Internet-of-Things devices for supporting their sustainable lifelong learning. Then, the convergence rate of the FL algorithm is derived, which is shown to depend on the data utility (defined as the number of used training samples) in each training iteration. Thus, to accelerate the convergence rate and reduce the training latency, a data utility maximization problem for each iteration is formulated, under several practical constraints on the limited time, bandwidth (i.e., number of subcarriers), computation frequency, and energy supply. The problem is mixed-integer and non-convex, and hence NP-hard. To solve the problem, an optimal joint device selection and resource allocation (JDSRA) scheme is proposed. In this scheme, a distributed on-device resource allocation problem is first solved to determine the minimum required number of subcarriers for each device, followed by a dynamic programming approach for attaining the optimal device selection policy. In particular, no global channel state information (CSI) sharing is needed to execute the scheme. Finally, extensive experiments are presented to demonstrate the performance of the proposed optimal algorithm.
联合学习(FL)是一种很有前途的技术,可从分布在物联网网络中的海量数据中提炼人工智能,同时保护数据隐私。然而,由于有限的无线电资源、计算能力和物联网设备的电池寿命等原因,FL 的高效部署面临着一些挑战。为了应对这些挑战,本研究首先在物联网设备上启用了能量收集技术,以支持其可持续的终身学习。然后,推导出 FL 算法的收敛速率,并证明该速率取决于每次训练迭代中的数据效用(定义为所用训练样本的数量)。因此,为了加快收敛速度并减少训练延迟,在有限的时间、带宽(即子载波数)、计算频率和能量供应等几个实际约束条件下,为每次迭代提出了一个数据效用最大化问题。该问题是混合整数和非凸问题,因此具有 NP 难度。为了解决这个问题,我们提出了一种最优联合设备选择和资源分配(JDSRA)方案。在该方案中,首先要解决分布式设备上资源分配问题,以确定每个设备所需的最小子载波数,然后采用动态编程方法实现最优设备选择策略。特别是,执行该方案无需共享全局信道状态信息(CSI)。最后,通过大量实验证明了所提最优算法的性能。
{"title":"Federated Learning With Energy Harvesting Devices","authors":"Li Zeng;Dingzhu Wen;Guangxu Zhu;Changsheng You;Qimei Chen;Yuanming Shi","doi":"10.1109/TGCN.2023.3310569","DOIUrl":"10.1109/TGCN.2023.3310569","url":null,"abstract":"Federated learning (FL) is a promising technique for distilling artificial intelligence from massive data distributed in Internet-of-Things networks, while keeping data privacy. However, the efficient deployment of FL faces several challenges due to, e.g., limited radio resources, computation capabilities, and battery lives of Internet-of-Things devices. To address these challenges, in this work, the energy harvesting technique is first enabled on Internet-of-Things devices for supporting their sustainable lifelong learning. Then, the convergence rate of the FL algorithm is derived, which is shown to depend on the data utility (defined as the number of used training samples) in each training iteration. Thus, to accelerate the convergence rate and reduce the training latency, a data utility maximization problem for each iteration is formulated, under several practical constraints on the limited time, bandwidth (i.e., number of subcarriers), computation frequency, and energy supply. The problem is mixed-integer and non-convex, and hence NP-hard. To solve the problem, an optimal joint device selection and resource allocation (JDSRA) scheme is proposed. In this scheme, a distributed on-device resource allocation problem is first solved to determine the minimum required number of subcarriers for each device, followed by a dynamic programming approach for attaining the optimal device selection policy. In particular, no global channel state information (CSI) sharing is needed to execute the scheme. Finally, extensive experiments are presented to demonstrate the performance of the proposed optimal algorithm.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"62571450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Convergence Analysis and Latency Minimization for Semi-Federated Learning in Massive IoT Networks 大规模物联网网络中半联邦学习的收敛分析与时延最小化
IF 4.8 2区 计算机科学 Q1 Computer Science Pub Date : 2023-08-29 DOI: 10.1109/TGCN.2023.3309657
Jianyang Ren;Wanli Ni;Hui Tian;Gaofeng Nie
As the number of sensors becomes massive in Internet of Things (IoT) networks, the amount of data is humongous. To process data in real-time while protecting user privacy, federated learning (FL) has been regarded as an enabling technique to push edge intelligence into IoT networks with massive devices. However, FL latency increases dramatically due to the increase of the number of parameters in deep neural network and the limited computation and communication capabilities of IoT devices. To address this issue, we propose a semi-federated learning (SemiFL) paradigm in which network pruning and over-the-air computation are efficiently applied. To be specific, each small base station collects the raw data from its served sensors and trains its local pruned model. After that, the global aggregation of local gradients is achieved through over-the-air computation. We first analyze the performance of the proposed SemiFL by deriving its convergence upper bound. To reduce latency, a convergence-constrained SemiFL latency minimization problem is formulated. By decoupling the original problem into several sub-problems, iterative algorithms are designed to solve them efficiently. Finally, numerical simulations are conducted to verify the effectiveness of our proposed scheme in reducing latency and guaranteeing the identification accuracy.
随着物联网(IoT)网络中传感器的数量越来越多,数据量也越来越大。为了在保护用户隐私的同时实时处理数据,联邦学习(FL)被认为是一种将边缘智能推向具有大量设备的物联网网络的使能技术。然而,由于深度神经网络中参数数量的增加以及物联网设备有限的计算和通信能力,FL延迟会急剧增加。为了解决这个问题,我们提出了一种半联邦学习(SemiFL)范式,其中有效地应用了网络修剪和空中计算。具体来说,每个小型基站从其服务的传感器收集原始数据并训练其本地修剪模型。然后,通过空中计算实现局部梯度的全局聚合。我们首先通过推导其收敛上界来分析所提出的半ifl的性能。为了减少延迟,提出了收敛约束的半ifl延迟最小化问题。通过将原问题解耦为若干子问题,设计迭代算法进行有效求解。最后,通过数值仿真验证了所提方案在降低时延和保证识别精度方面的有效性。
{"title":"Convergence Analysis and Latency Minimization for Semi-Federated Learning in Massive IoT Networks","authors":"Jianyang Ren;Wanli Ni;Hui Tian;Gaofeng Nie","doi":"10.1109/TGCN.2023.3309657","DOIUrl":"10.1109/TGCN.2023.3309657","url":null,"abstract":"As the number of sensors becomes massive in Internet of Things (IoT) networks, the amount of data is humongous. To process data in real-time while protecting user privacy, federated learning (FL) has been regarded as an enabling technique to push edge intelligence into IoT networks with massive devices. However, FL latency increases dramatically due to the increase of the number of parameters in deep neural network and the limited computation and communication capabilities of IoT devices. To address this issue, we propose a semi-federated learning (SemiFL) paradigm in which network pruning and over-the-air computation are efficiently applied. To be specific, each small base station collects the raw data from its served sensors and trains its local pruned model. After that, the global aggregation of local gradients is achieved through over-the-air computation. We first analyze the performance of the proposed SemiFL by deriving its convergence upper bound. To reduce latency, a convergence-constrained SemiFL latency minimization problem is formulated. By decoupling the original problem into several sub-problems, iterative algorithms are designed to solve them efficiently. Finally, numerical simulations are conducted to verify the effectiveness of our proposed scheme in reducing latency and guaranteeing the identification accuracy.","PeriodicalId":13052,"journal":{"name":"IEEE Transactions on Green Communications and Networking","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48625459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
IEEE Transactions on Green Communications and Networking
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1