China Communications最新文献

筛选
英文 中文
Analysis and optimization of validation procedure in blockchain-enhanced wireless resource sharing and transactions 区块链增强无线资源共享和交易中验证程序的分析和优化
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.ea.2021-0856.202302
Enyu Du, Yang Gao, Wenjun Wu, Zhaoxin Yang, Yufeng Yin, Pengbo Si
{"title":"Analysis and optimization of validation procedure in blockchain-enhanced wireless resource sharing and transactions","authors":"Enyu Du, Yang Gao, Wenjun Wu, Zhaoxin Yang, Yufeng Yin, Pengbo Si","doi":"10.23919/jcc.ea.2021-0856.202302","DOIUrl":"https://doi.org/10.23919/jcc.ea.2021-0856.202302","url":null,"abstract":"To ensure the security of resource and intelligence sharing in 6G, blockchain has been widely adopted in wireless communications and applications. Although blockchain can ensure the traceability and non-tamperability of data in the concatenated blocks, it cannot guarantee the honest behaviors of users in the application before the generation of transactions. Thus, additional technologies are required to ensure that the source of blockchain data is reliable. In this paper, the detailed procedure is designed for the application-oriented task validation in the blockchain-enhanced computing resource sharing and transactions in ultra dense networks (UDN). The corresponding queuing model is built and analyzed with the consideration of the wireless re-transmission and the probability of malicious deception by users. Based on the analysis results, the UDN deployment is optimized to save network cost while ensuring latency performance. Numerical results verify our analysis, and the optimized system deployment including the number and service capacities of both base stations and mobile edge computing (MEC) servers are also given with various system settings.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136139702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Anti-jamming and anti-eavesdropping in A2G communication system with jittering UAV 抖动无人机A2G通信系统的抗干扰与防窃听
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.fa.2021-0430.202310
Huici Wu, Yang Wen, Xiaofeng Tao, Jin Xu
{"title":"Anti-jamming and anti-eavesdropping in A2G communication system with jittering UAV","authors":"Huici Wu, Yang Wen, Xiaofeng Tao, Jin Xu","doi":"10.23919/jcc.fa.2021-0430.202310","DOIUrl":"https://doi.org/10.23919/jcc.fa.2021-0430.202310","url":null,"abstract":"This paper focuses on anti-jamming and anti-eavesdropping problem in air-to-ground (A2G) communication networks considering the impact of body jitter of unmanned aerial vehicle (UAV). A full-duplex (FD) active ground eavesdropper launches jamming attack while eavesdropping to stimulate the legitimate transmitter (i.e., UAV) to increase its transmission power. The legitimate transmitter's objective is to against the simultaneous wiretapping and jamming with a robust and power-efficient transmission scheme. The active eavesdropper aims to minimize the system secrecy rate. To study the interaction between the legitimate transmitter and the active eavesdropper, a non-cooperative game framework is formulated. Detailed, considering the impact of UAV jitter on antenna array response and secrecy performance, we first investigate the UAV's transmission power minimization problem for the worst scenario with minimum legitimate data rate and maximum eavesdropping data rate under UAV jitter. Then, the active eavesdropper's secrecy rate minimization problem with the worst scenario is investigated by optimizing its jamming strategy. Nash equilibrium is proved to be existed and obtained with the proposed iterative algorithm. Finally, extensive numerical results are provided to evaluate the system secrecy performance and to show the secrecy performance gains of the proposed method.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136200044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
A fine synchronization method for coherent fast frequency hopping 相干快速跳频的精细同步方法
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.fa.2022-0599.202310
Xuanhe Yang, Weike Zhang, Shixun Luo, Chang Li, Xiaqing Miao, Aihua Wang
{"title":"A fine synchronization method for coherent fast frequency hopping","authors":"Xuanhe Yang, Weike Zhang, Shixun Luo, Chang Li, Xiaqing Miao, Aihua Wang","doi":"10.23919/jcc.fa.2022-0599.202310","DOIUrl":"https://doi.org/10.23919/jcc.fa.2022-0599.202310","url":null,"abstract":"Coherent fast frequency hopping (CFFH) is attracting growing attention owing to its good antijamming performance and the coherent combining ability. However, compared with the conventional non-coherent fast frequency hopping, CFFH requires a more precise system synchronization. In this paper, we propose a new fine synchronization algorithm for CFFH. This algorithm consists two stages, namely, open-loop stage and closed-loop stage. In the open-loop stage, a grid-based search parameter estimation method is proposed. In the closed-loop stage, we construct a fully coherent phase-locked loop (PLL) and a delay-locked loop (DLL) with decoding feedback structure to perform further fine estimation of the system clock skew and time delay, respectively. Moreover, we analyze the effect of the search parameter settings on the estimation error and derive the root mean squared error (RMSE) of estimates in the steady state of the closed-loop stage. Finally, through simulation, the RMSE performance are compared with the corresponding Cramer-Rao low bound (CRLB) and conventional code loop estimation to show the effectiveness of proposed algorithm.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136200056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
System outage probability and diversity analysis of a SWIPT based two-way DF relay network under transceiver hardware impairments 收发器硬件损坏下基于SWIPT的双向DF中继网络系统中断概率和分集分析
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.ea.2021-0184.202302
Guangyue Lu, Zhipeng Liu, Yinghui Ye, Xiaoli Chu
{"title":"System outage probability and diversity analysis of a SWIPT based two-way DF relay network under transceiver hardware impairments","authors":"Guangyue Lu, Zhipeng Liu, Yinghui Ye, Xiaoli Chu","doi":"10.23919/jcc.ea.2021-0184.202302","DOIUrl":"https://doi.org/10.23919/jcc.ea.2021-0184.202302","url":null,"abstract":"This paper investigates the system outage performance of a simultaneous wireless information and power transfer (SWIPT) based two-way decode-and-forward (DF) relay network, where potential hardware impairments (HIs) in all transceivers are considered. After harvesting energy and decoding messages simultaneously via a power splitting scheme, the energy-limited relay node forwards the decoded information to both terminals. Each terminal combines the signals from the direct and relaying links via selection combining. We derive the system outage probability under independent but non-identically distributed Nakagami-m fading channels. It reveals an overall system ceiling (OSC) effect, i.e., the system falls in outage if the target rate exceeds an OSC threshold that is determined by the levels of HIs. Furthermore, we derive the diversity gain of the considered network. The result reveals that when the transmission rate is below the OSC threshold, the achieved diversity gain equals the sum of the shape parameter of the direct link and the smaller shape parameter of the terminal-to-relay links; otherwise, the diversity gain is zero. This is different from the amplify-and-forward (AF) strategy, under which the relaying links have no contribution to the diversity gain. Simulation results validate the analytical results and reveal that compared with the AF strategy, the SWIPT based two-way relaying links under the DF strategy are more robust to HIs and achieve a lower system outage probability.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"258 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135996511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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: 1
A study of ensemble feature selection and adversarial training for malicious user detection 针对恶意用户检测的集成特征选择与对抗训练研究
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.ea.2021-0512.202302
Linjie Zhang, Xiaoyan Zhu, Jianfeng Ma
{"title":"A study of ensemble feature selection and adversarial training for malicious user detection","authors":"Linjie Zhang, Xiaoyan Zhu, Jianfeng Ma","doi":"10.23919/jcc.ea.2021-0512.202302","DOIUrl":"https://doi.org/10.23919/jcc.ea.2021-0512.202302","url":null,"abstract":"The continuously booming of information technology has shed light on developing a variety of communication networks, multimedia, social networks and Internet of Things applications. However, users inevitably suffer from the intrusion of malicious users. Some studies focus on static characteristics of malicious users, which is easy to be bypassed by camouflaged malicious users. In this paper, we present a malicious user detection method based on ensemble feature selection and adversarial training. Firstly, the feature selection alleviates the dimension disaster problem and achieves more accurate classification performance. Secondly, we embed features into the multidimensional space and aggregate it into a feature map to encode the explicit content preference and implicit interaction preference. Thirdly, we use an effective ensemble learning which could avoid over-fitting and has good noise resistance. Finally, we propose a datadriven neural network detection model with the regularization technique adversarial training to deeply analyze the characteristics. It simplifies the parameters, obtaining more robust interaction features and pattern features. We demonstrate the effectiveness of our approach with numerical simulation results for malicious user detection, where the robustness issues are notable concerns.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136139699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
UAMP-based delay-Doppler channel estimation for OTFS systems 基于uamp的OTFS系统延迟-多普勒信道估计
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.fa.2023-0067.202310
Zhongjie Li, Weijie Yuan, Qinghua Guo, Nan Wu, Ji Zhang
{"title":"UAMP-based delay-Doppler channel estimation for OTFS systems","authors":"Zhongjie Li, Weijie Yuan, Qinghua Guo, Nan Wu, Ji Zhang","doi":"10.23919/jcc.fa.2023-0067.202310","DOIUrl":"https://doi.org/10.23919/jcc.fa.2023-0067.202310","url":null,"abstract":"Orthogonal time frequency space (OTFS) technique, which modulates data symbols in the delay-Doppler (DD) domain, presents a potential solution for supporting reliable information transmission in high-mobility vehicular networks. In this paper, we study the issues of DD channel estimation for OTFS in the presence of fractional Doppler. We first propose a channel estimation algorithm with both low complexity and high accuracy based on the unitary approximate message passing (UAMP), which exploits the structured sparsity of the effective DD domain channel using hidden Markov model (HMM). The empirical state evolution (SE) analysis is then leveraged to predict the performance of our proposed algorithm. To refine the hyperparameters in the proposed algorithm, we derive the update criterion for the hyperparameters through the expectation-maximization (EM) algorithm. Finally, Our simulation results demonstrate that our proposed algorithm can achieve a significant gain over various baseline schemes.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136200054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Cross-band spectrum prediction algorithm based on data conversion using generative adversarial networks 基于生成对抗网络数据转换的跨频带频谱预测算法
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.ea.2022-0096.202302
Chuang Peng, Rangang Zhu, Mengbo Zhang, Lunwen Wang
{"title":"Cross-band spectrum prediction algorithm based on data conversion using generative adversarial networks","authors":"Chuang Peng, Rangang Zhu, Mengbo Zhang, Lunwen Wang","doi":"10.23919/jcc.ea.2022-0096.202302","DOIUrl":"https://doi.org/10.23919/jcc.ea.2022-0096.202302","url":null,"abstract":"Spectrum prediction is one of the new techniques in cognitive radio that predicts changes in the spectrum state and plays a crucial role in improving spectrum sensing performance. Prediction models previously trained in the source band tend to perform poorly in the new target band because of changes in the channel. In addition, cognitive radio devices require dynamic spectrum access, which means that the time to retrain the model in the new band is minimal. To increase the amount of data in the target band, we use the GAN to convert the data of source band into target band. First, we analyze the data differences between bands and calculate FID scores to identify the available bands with the slightest difference from the target predicted band. The original GAN structure is unsuitable for converting spectrum data, and we propose the spectrum data conversion GAN (SDC-GAN). The generator module consists of a convolutional network and an LSTM module that can integrate multiple features of the data and can convert data from the source band to the target band. Finally, we use the generated target band data to train the prediction model. The experimental results validate the effectiveness of the proposed algorithm.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136139700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
A deep reinforcement learning-based power control scheme for the 5G wireless systems 基于深度强化学习的5G无线系统功率控制方案
3区 计算机科学
China Communications Pub Date : 2023-10-01 DOI: 10.23919/jcc.ea.2021-0523.202302
Renjie Liang, Haiyang Lyu, Jiancun Fan
{"title":"A deep reinforcement learning-based power control scheme for the 5G wireless systems","authors":"Renjie Liang, Haiyang Lyu, Jiancun Fan","doi":"10.23919/jcc.ea.2021-0523.202302","DOIUrl":"https://doi.org/10.23919/jcc.ea.2021-0523.202302","url":null,"abstract":"In the fifth generation (5G) wireless system, a closed-loop power control (CLPC) scheme based on deep Q learning network (DQN) is introduced to intelligently adjust the transmit power of the base station (BS), which can improve the user equipment (UE) received signal to interference plus noise ratio (SINR) to a target threshold range. However, the selected power control (PC) action in DQN is not accurately matched the fluctuations of the wireless environment. Since the experience replay characteristic of the conventional DQN scheme leads to a possibility of insufficient training in the target deep neural network (DNN). As a result, the Q-value of the sub-optimal PC action exceed the optimal one. To solve this problem, we propose the improved DQN scheme. In the proposed scheme, we add an additional DNN to the conventional DQN, and set a shorter training interval to speed up the training of the DNN in order to fully train it. Finally, the proposed scheme can ensure that the Q value of the optimal action remains maximum. After multiple episodes of training, the proposed scheme can generate more accurate PC actions to match the fluctuations of the wireless environment. As a result, the UE received SINR can achieve the target threshold range faster and keep more stable. The simulation results prove that the proposed scheme outperforms the conventional schemes.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136139705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
SNWPM: A Siamese network based wireless positioning model resilient to partial base stations unavailable SNWPM:一种基于Siamese网络的无线定位模型,可适应部分基站不可用的情况
3区 计算机科学
China Communications Pub Date : 2023-09-01 DOI: 10.23919/jcc.fa.2023-0064.202309
Yasong Zhu, Jiabao Wang, Yi Sun, Bing Xu, Peng Liu, Zhisong Pan, Wangdong Qi
{"title":"SNWPM: A Siamese network based wireless positioning model resilient to partial base stations unavailable","authors":"Yasong Zhu, Jiabao Wang, Yi Sun, Bing Xu, Peng Liu, Zhisong Pan, Wangdong Qi","doi":"10.23919/jcc.fa.2023-0064.202309","DOIUrl":"https://doi.org/10.23919/jcc.fa.2023-0064.202309","url":null,"abstract":"Artificial intelligence (AI) models are promising to improve the accuracy of wireless positioning systems, particularly in indoor environments where unpredictable radio propagation channel is a great challenge. Although great efforts have been made to explore the effectiveness of different AI models, it is still an open problem whether these models, trained with the data collected from all base stations (BSs), could work when some BSs are unavailable. In this paper, we make the first effort to enhance the generalization ability of AI wireless positioning model to adapt to the scenario where only partial BSs work. Particularly, a Siamese Network based Wireless Positioning Model (SNWPM) is proposed to predict the location of mobile user equipment from channel state information (CSI) collected from 5G BSs. Furthermore, a Feature Aware Attention Module (FAAM) is introduced to reinforce the capability of feature extraction from CSI data. Experiments are conducted on the 2022 Wireless Communication AI Competition (WAIC) dataset. The proposed SNWPM achieves decimeter-level positioning accuracy even if the data of partial BSs are unavailable. Compared with other AI models, the proposed SNWPM can reduce the positioning error by nearly 50% to more than 60% while using less parameters and lower computation resources.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135299505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Performance analysis of the packet-based PNT service in NGSO broadband satellite communication systems NGSO宽带卫星通信系统中基于分组的PNT业务性能分析
3区 计算机科学
China Communications Pub Date : 2023-09-01 DOI: 10.23919/jcc.fa.2021-0732.202309
Xi Chen, Qihui Wei, Yafeng Zhan, Linling Kuang
{"title":"Performance analysis of the packet-based PNT service in NGSO broadband satellite communication systems","authors":"Xi Chen, Qihui Wei, Yafeng Zhan, Linling Kuang","doi":"10.23919/jcc.fa.2021-0732.202309","DOIUrl":"https://doi.org/10.23919/jcc.fa.2021-0732.202309","url":null,"abstract":"Providing alternative PNT service to GNSS-challenged users will be an important function of next-generation NGSO broadband satellite communication systems. Herein, a packet-based PNT service architecture in NGSO broadband systems is proposed in which a primary satellite and selected assistant satellites work together to provide PNT service to requesting users. Its positioning performance bounds are mathematically formulated by rigorously analyzing the bounds constrained by different waveforms. Simulations are conducted on different configurations of Walker Delta MEO constellations and Walker Star LEO constellations for corroboration, revealing the following: (1) Both MEO and LEO constellations achieve sub-meter-level positioning precision given enough satellites. (2) Compared to the GNSS Doppler-based velocity estimation method, the position advance based velocity estimation algorithm is more precise and applicable to the PNT service in NGSO broadband systems. (3) To provide PNT service to users in GNSS-challenged environments, the primary and each assistant satellite need only ∼0.1%o of the time of one downlink beam.","PeriodicalId":9814,"journal":{"name":"China Communications","volume":"195 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135299506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
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
确定
请完成安全验证×
相关产品
×
本文献相关产品
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 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术官方微信
小红书