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Standard-definition White-light,High-definition White-light versus Narrow-band Imaging Endoscopy for Detecting Colorectal Adenomas:A Multicenter Randomized Controlled Trial
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作者 Chang-wei DUAN Hui-hong ZHAI +10 位作者 Hui XIE Xian-zong MA Dong-liang YU Lang YANG Xin WANG Yu-fen TANG Jie ZHANG Hui SU Jian-qiu SHENG Jun-feng XU Peng JIN 《Current Medical Science》 SCIE CAS 2024年第3期554-560,共7页
Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colore... Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colorectal lesions in the Chinese population.Methods This was a multicenter,single-blind,randomized,controlled trial with a non-inferiority design.Patients undergoing endoscopy for physical examination,screening,and surveillance were enrolled from July 2017 to December 2020.The primary outcome measure was the adenoma detection rate(ADR),defined as the proportion of patients with at least one adenoma detected.The associated factors for detecting adenomas were assessed using univariate and multivariate logistic regression.Results Out of 653 eligible patients enrolled,data from 596 patients were analyzed.The ADRs were 34.5%in the SD-WL group,33.5%in the HD-WL group,and 37.5%in the HD-NBI group(P=0.72).The advanced neoplasm detection rates(ANDRs)in the three arms were 17.1%,15.5%,and 10.4%(P=0.17).No significant differences were found between the SD group and HD group regarding ADR or ANDR(ADR:34.5%vs.35.6%,P=0.79;ANDR:17.1%vs.13.0%,P=0.16,respectively).Similar results were observed between the HD-WL group and HD-NBI group(ADR:33.5%vs.37.7%,P=0.45;ANDR:15.5%vs.10.4%,P=0.18,respectively).In the univariate and multivariate logistic regression analyses,neither HD-WL nor HD-NBI led to a significant difference in overall adenoma detection compared to SD-WL(HD-WL:OR 0.91,P=0.69;HD-NBI:OR 1.15,P=0.80).Conclusion HD-NBI and HD-WL are comparable to SD-WL for overall adenoma detection among Chinese outpatients.It can be concluded that HD-NBI or HD-WL is not superior to SD-WL,but more effective instruction may be needed to guide the selection of different endoscopic methods in the future.Our study’s conclusions may aid in the efficient allocation and utilization of limited colonoscopy resources,especially advanced imaging technologies. 展开更多
关键词 standard-definition white-light endoscopy high-definition white-light endoscopy narrow-band imaging colonoscopy colorectal cancer screening adenoma detection rate
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Software-aided efficient identification of the components of compound formulae and their metabolites in rats by UHPLC/IM-QTOF-MS and an in-house high-definition MS^(2) library: Sishen formula as a case
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作者 Lili Hong Wei Wang +9 位作者 Shiyu Wang Wandi Hu Yuyang Sha Xiaoyan Xu Xiaoying Wang Kefeng Li Hongda Wang Xiumei Gao De-an Guo Wenzhi Yang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第10期1484-1495,共12页
Identifying the compound formulae-related xenobiotics in bio-samples is full of challenges.Conventional strategies always exhibit the insufficiencies in overall coverage,analytical efficiency,and degree of automation,... Identifying the compound formulae-related xenobiotics in bio-samples is full of challenges.Conventional strategies always exhibit the insufficiencies in overall coverage,analytical efficiency,and degree of automation,and the results highly rely on the personal knowledge and experience.The goal of this work was to establish a software-aided approach,by integrating ultra-high performance liquid chromatography/ion-mobility quadrupole time-of-flight mass spectrometry(UHPLC/IM-QTOF-MS)and in-house high-definition MS^(2) library,to enhance the identification of prototypes and metabolites of the compound formulae in vivo,taking Sishen formula(SSF)as a template.Seven different MS2 acquisition methods were compared,which demonstrated the potency of a hybrid scan approach(namely high-definition data-independent/data-dependent acquisition(HDDIDDA))in the identification precision,MS1 coverage,and MS^(2) spectra quality.The HDDIDDA data for 55 reference compounds,four component drugs,and SSF,together with the rat bio-samples(e.g.,plasma,urine,feces,liver,and kidney),were acquired.Based on the UNIFI™platform(Waters),the efficient data processing workflows were established by combining mass defect filtering(MDF)-induced classification,diagnostic product ions(DPIs),and neutral loss filtering(NLF)-dominated structural confirmation.The high-definition MS^(2) spectral libraries,dubbed in vitro-SSF and in vivo-SSF,were elaborated,enabling the efficient and automatic identification of SSF-associated xenobiotics in diverse rat bio-samples.Consequently,118 prototypes and 206 metabolites of SSF were identified,with the identification rate reaching 80.51%and 79.61%,respectively.The metabolic pathways mainly involved the oxidation,reduction,hydrolysis,sulfation,methylation,demethylation,acetylation,glucuronidation,and the combined reactions.Conclusively,the proposed strategy can drive the identification of compound formulae-related xenobiotics in vivo in an intelligent manner. 展开更多
关键词 Ultra-high performance liquid chromatography/ion-mobility quadrupole time-of-flight mass spectrometry(UHPLC/IM-QTOF-MS) Hybrid scan high-definition MS^(2)spectral library Sishen formula
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High-definition colonoscopy with i-Scan:Better diagnosis for small polyps and flat adenomas 被引量:12
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作者 Pier Alberto Testoni Chiara Notaristefano +2 位作者 Cristian Vailati Milena Di Leo Edi Viale 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第37期5231-5239,共9页
AIM: To investigate if high-definition (HD) colonoscope with i-Scan gave a higher detection rate of mucosal le- sions vs standard white-light instruments. METHODS: Data were collected from the computer- ized datab... AIM: To investigate if high-definition (HD) colonoscope with i-Scan gave a higher detection rate of mucosal le- sions vs standard white-light instruments. METHODS: Data were collected from the computer- ized database of the endoscopy unit of our tertiary referral center. We retrospectively analyzed 1101 con- secutive colonoscopies that were performed over 1 year with standard white-light (n = 849) or HD+ with i-Scan (n = 252) instruments by four endoscopists, in an outpatient setting. Colonoscopy records included patients' main details and family history for colorectal cancer, indication for colonoscopy (screening, diagnos- tic or surveillance), type of instrument used (standard white-light or HD+ plus i-Scan), name of endoscopist and bowel preparation. Records for each procedure included whether the cecum was reached or not and the reason for failure, complications during or imme- diately after the procedure, and number, size, location and characteristics of the lesions. Polyps or protruding lesions were defined as sessile or pedunculated, and nonprotruding lesions were defined according to Paris classification. For each lesion, histological diagnosis was recorded. RESULTS: Eight hundred and forty-nine colonosco- pies were carried with the standard white-light video colonoscope and 252 with the HD+ plus i-Scan video colonoscope, The four endoscopists did 264, 300, 276 and 261 procedures, respectively; 21.6%, 24.0%, 21.7% and 24.1% of them with the HD+ plus i-Scan technique. There were no significant differences be- tween the four endoscopists in either the number of procedures done or the proportions of each imaging technique used. Both techniques detected one or more mucosal lesions in 522/1101 procedures (47.4%). The overall number of lesions recognized was 1266; 645 in the right colon and 621 in the left. A significantly higher number of colonoscopies recognized lesions in the HD+ plus i-Scan mode (171/252 = 67.9%) than with the standard white-light technique (408/849 = 48.1%) (P 〈 0.0001). HD+ with i-Scan colonoscopies identified more lesions than standard white-light imag- ing (459/252 and 807/849, P 〈 0.0001), in the right or left colon (mean :1: SD, 1.62±1.36 vs 1.33±0.73, P 〈 0.003 and 1.55±0.98 vs 1.17±0.93, P = 0.033), more lesions 〈 10 mm (P 〈 0.0001) or nonprotruding (P 〈 0.022), and flat polyps (P = 0.04). The cumulative mean number of lesions per procedure detected by the four endoscopists was significantly higher with HD+ with i-Scan than with standard white-light imaging (1.82 ± 2.89 vs 0.95± 1.35, P 〈 0.0001). CONCLUSION: HD imaging with i-Scan during the withdrawal phase of colonoscopy significantly increased the detection of colonic mucosal lesions, particularly small and nonprotruding polyps. 展开更多
关键词 COLONOSCOPY high-definition with i-Scancolonoscopy White-light colonoscopy Colonic polyps Nonprotruding lesions Adenoma detection rate With-drawal time Surface enhancement Contrast enhance-ment Tone enhancement
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Optical diagnosis of colorectal polyps using high-definition i-scan: An educational experience
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作者 Mariёlle WE Bouwens Rogier de Ridder +4 位作者 Ad AM Masclee Ann Driessen Robert G Riedl Bjorn Winkens Silvia Sanduleanu 《World Journal of Gastroenterology》 SCIE CAS 2013年第27期4334-4343,共10页
AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still ... AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still images, comprising twin pictures (surface enhancement and tone enhancement), collected at our university hospital. We defined endoscopic features of adenomatous and non-adenomatous polyps, according to the following parameters:color, surface pattern and vascular pattern. We familiarized the participating endoscopists on optical diagnosis of colorectal polyps using a 20-min didactic training session. All endoscopists were asked to evaluate an image set of 50 colorectal polyps with regard to polyp histology. We classified the diagnoses into high confidence (i.e., cases in which the endoscopist could assign a diagnosis with certainty) and low confidence diagnoses (i.e., cases in which the endoscopist preferred to send the polyp for formal histology). Mean sensitivity, specificity and accuracy per endoscopist/image were computed and differences between groups tested using independent-samples t tests. High vs low confidence diagnoses were compared using the pairedsamples t test. RESULTS:Eleven endoscopists without previous experience on optical diagnosis evaluated a total of 550 images (396 adenomatous, 154 non-adenomatous). Mean sensitivity, specificity and accuracy for diagnosing adenomas were 79.3%, 85.7% and 81.1%, respectively. No significant differences were found between gastroenterologists and trainees regarding performances of optical diagnosis (mean accuracy 78.0%vs 82.9%,P = 0.098). Diminutive lesions were predicted with a lower mean accuracy as compared to non-diminutive lesions (74.2% vs 93.1%, P = 0.008). A total of 446 (81.1%) diagnoses were made with high confidence. High confidence diagnoses corresponded to a significantly higher mean accuracy than low confidence diagnoses (84.0% vs 64.3%, P = 0.008). A total of 319 (58.0%) images were evaluated as having excellent quality. Considering excellent quality images in conjunction with high confidence diagnosis, overall accuracy increased to 92.8%. CONCLUSION:After a single training session, endoscopists with varying levels of experience can already provide optical diagnosis with an accuracy of 84.0%. 展开更多
关键词 COLONOSCOPY high-definition i-scan Optical diagnosis Colorectal POLYPS Training
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A Reliable Adaptive High-Definition Transmission System for Distance Learning
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作者 徐奇 李鹤廷 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第6期740-743,共4页
There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great ... There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great challenge for deployment. In this paper, a novel high-definition (HD) video transmission system was proposed which depends upon reliable compound multicast protocols and QoS control over the various kinds of networks. This system detects client's network condition and assigns it to a proper proxy. Each proxy is capable of detecting network parameters and adaptively tuning such transport parameters as bit rate, video resolution, frame rate and QoS mechanisms to this condition. It also provides FEC error recovery under consideration of characteristics of MPEG4 video codec. Our simulation demonstrates that different network clients such as ADSL, CERNET, and CERNET2 can receive more video reliability with less delay. 展开更多
关键词 ADAPTIVE high-definition(HD) transmission system distance learning RELIABLE compound MULTICAST protocol (RCMP)
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Cooperative Covert Communication in Multi-Antenna Broadcast Channels
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作者 Qiao Sen Liu Guangjie +1 位作者 Ji Xiaopeng Liu Weiwei 《China Communications》 SCIE CSCD 2024年第6期246-260,共15页
With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two... With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two-user cooperative multi-antenna broadcast channel.We focus on the issue that the deteriorated reliability and undetectability are mainly affected by the transmission power.To tackle this issue,we design a scheme based on beamforming to increase the reliability and undetectability of wireless covert communication in the multi-antenna broadcast channel.We first modeled and analyzed the cooperative multi-antenna broadcasting system,and put forward the target question.Then we use the SCA(successive convex approximation)algorithm to transform the target problem into a series of convex subproblems.Then the convex problems are solved and the covert channel capacity is calculated.In order to verify the effectiveness of the scheme,we conducted simulation verification.The simulation results show that the proposed beamforming scheme can effectively improve the reliability and undetectability of covert communication in multi-antenna broadcast channels. 展开更多
关键词 BEAMFORMING covert communication multi-antenna broadcast channels OFDM
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Multi-User Semantic Fusion for Semantic Communications over Degraded Broadcast Channels
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作者 Wu Tong Chen Zhiyong +2 位作者 Tao Meixia Xia Bin Zhang Wenjun 《China Communications》 SCIE CSCD 2024年第10期86-100,共15页
Degraded broadcast channels(DBC) are a typical multiuser communication scenario, Semantic communications over DBC still lack in-depth research. In this paper, we design a semantic communications approach based on mult... Degraded broadcast channels(DBC) are a typical multiuser communication scenario, Semantic communications over DBC still lack in-depth research. In this paper, we design a semantic communications approach based on multi-user semantic fusion for wireless image transmission over DBC. The transmitter extracts semantic features for two users separately and then effectively fuses them for broadcasting by leveraging semantic similarity. Unlike traditional allocation of time, power, or bandwidth, the semantic fusion scheme can dynamically control the weight of the semantic features of the two users to balance their performance. Considering the different channel state information(CSI) of both users over DBC,a DBC-Aware method is developed that embeds the CSI of both users into the joint source-channel coding encoder and fusion module to adapt to the channel.Experimental results show that the proposed system outperforms the traditional broadcasting schemes. 展开更多
关键词 channel adaptability degraded broadcasting channels semantic communications semantic fusion
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A Deep Learning Based Broadcast Approach for Image Semantic Communication over Fading Channels
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作者 Ma Kangning Shi Yuxuan +1 位作者 Shao Shuo Tao Meixia 《China Communications》 SCIE CSCD 2024年第7期78-94,共17页
We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adapt... We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adaptive semantic transmission in terms of different channel states.We combine the classic broadcast approach with the image transformer to implement this adaptive joint source and channel coding(JSCC)scheme.Specifically,we utilize the neural network(NN)to jointly optimize the hierarchical image compression and superposition code mapping within this scheme.The learned transformers and codebooks allow recovering of the image with an adaptive quality and low error rate at the receiver side,in each channel state.The simulation results exhibit our proposed scheme can dynamically adapt the coding to the current channel state and outperform some existing intelligent schemes with the fixed coding block. 展开更多
关键词 broadcast approach deep learning fading channels semantic communication
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Design Method for Optimizing the Interactive Interface of Live Broadcasting Platform for the Elderly Users
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作者 WEI Bi-ze FAN Wei DUAN Ying-ke 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期167-178,共12页
In the era of network live broadcasting for everyone,the development of live broadcasting platforms is also more intelligent and diversified.However,in the face of a large group of elderly users,the interface interact... In the era of network live broadcasting for everyone,the development of live broadcasting platforms is also more intelligent and diversified.However,in the face of a large group of elderly users,the interface interaction design mode used is still mainly based on the interaction mode for young groups,and is not designed for elderly users.Therefore,a design method for optimizing the interaction interface of live broadcasting platform for elderly users was proposed in this study.Firstly,the case study method and Delphi expert survey method were used to determine the design needs of elderly users and the design mode was analysed.Secondly,the orthogonal design principle was used to design a test sample of the interactive interface of live broadcasting platform applicable for the elderly users,and then a user evaluation system was established to calculate the weights of the design elements using hierarchical analysis,and then the predictive relationship between the design mode of the interactive interface of live broadcasting platform and the elderly users was established by Quantitative Theory I.Finally,Genetic Algorithm was applied to generate the optimized design scheme.The results showed that the design method based on the Genetic Algorithm and the combination of Quantitative Theory can scientifically and effectively optimize the design of the interactive interface of the live broadcasting platform for the elderly users,and improve the experience of the elderly users. 展开更多
关键词 Live broadcasting platform Interaction design Elderly users Genetic Algorithm Quantitative Theory I
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Theoretical Analysis and Design Implementation of FM Broadcast Receiving System based on SDR
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作者 Yalan Yin Qi Wang +1 位作者 Jianrui Li Chunliu He 《Journal of Electronic Research and Application》 2024年第6期118-123,共6页
ADALM Pluto is a software-defined radio product.Based on theoretical analysis,this paper designs a Frequency Modulation(FM)broadcast receiving system using ADALM Pluto as a wireless receiver on the Simulink platform.T... ADALM Pluto is a software-defined radio product.Based on theoretical analysis,this paper designs a Frequency Modulation(FM)broadcast receiving system using ADALM Pluto as a wireless receiver on the Simulink platform.The simulation results show that the theoretical analysis is correct and the parameter settings are reasonable,and the Software-Defined Radio(SDR)has the characteristics of high performance,high ease of use,and low cost. 展开更多
关键词 SDR FM broadcasting Modulation and demodulation SIMULINK
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Programming Technology of IP Multicast and Broadcast Based on Socket 被引量:2
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作者 李冬霞 苏广川 沈瑛 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期316-321,共6页
Beginning with the simple introduction of socket which is the most commonly used application program interfaces in UNIX/LINUX communication domain, the concrete programming procedures to realize multicast and broadcas... Beginning with the simple introduction of socket which is the most commonly used application program interfaces in UNIX/LINUX communication domain, the concrete programming procedures to realize multicast and broadcast based on socket is provided, according to TCP/IP protocol in LINUX system. The acquiring and converting of broadcast destination address and multicast address, the setting of multicast options, the joining in and withdrawing from the multicast group, and the receiving and sending of datagram are all demonstrated in it, the related system calls and simple explication of C programming are also included. 展开更多
关键词 SOCKET MULTICAST broadcast LINUX
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基于Broadcast模板的交互系统 被引量:2
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作者 龚报钧 张泉灵 王树青 《计算机工程与应用》 CSCD 北大核心 1998年第5期34-35,37,共3页
本文提出了一种基于Broadcast模板开发交互系统的面向对象方法,并分析了此方法所带来的系统结构的清晰性、稳定性及软件部件的可重用性。
关键词 broadcast模板 软件重用 交互系统 软件工程
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广播标记(Broadcast Flag)技术 被引量:3
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作者 王磊 谢锦辉 《广播与电视技术》 北大核心 2006年第4期48-50,共3页
近来,业界都在讨论广播标记(BroadcastFlag)技术。本文详细介绍了广播标记技术产生的背景、原理与实现,以及争论的焦点问题;最后针对广播标记技术是否可以应用于我国的数字电视领域给出了我们的看法和建议。
关键词 广播标记 broadcast FLAG 再分发控制描述子 ATSC
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Wireless location algorithm using digital broadcasting signals based on neural network 被引量:1
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作者 柯炜 吴乐南 殷奎喜 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期394-398,共5页
In order to enhance the accuracy and reliability of wireless location under non-line-of-sight (NLOS) environments,a novel neural network (NN) location approach using the digital broadcasting signals is presented. ... In order to enhance the accuracy and reliability of wireless location under non-line-of-sight (NLOS) environments,a novel neural network (NN) location approach using the digital broadcasting signals is presented. By the learning ability of the NN and the closely approximate unknown function to any degree of desired accuracy,the input-output mapping relationship between coordinates and the measurement data of time of arrival (TOA) and time difference of arrival (TDOA) is established. A real-time learning algorithm based on the extended Kalman filter (EKF) is used to train the multilayer perceptron (MLP) network by treating the linkweights of a network as the states of the nonlinear dynamic system. Since the EKF-based learning algorithm approximately gives the minimum variance estimate of the linkweights,the convergence is improved in comparison with the backwards error propagation (BP) algorithm. Numerical results illustrate thatthe proposedalgorithmcanachieve enhanced accuracy,and the performance ofthe algorithmis betterthanthat of the BP-based NN algorithm and the least squares (LS) algorithm in the NLOS environments. Moreover,this location method does not depend on a particular distribution of the NLOS error and does not need line-of-sight ( LOS ) or NLOS identification. 展开更多
关键词 digital broadcasting signals neural network extended Kalman filter (EKF) backwards error propagation algorithm multilayer perceptron
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使用Broadcast Disks方法分布的空中位图索引
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作者 洪圆 孙未未 施伯乐 《计算机工程》 CAS CSCD 北大核心 2006年第2期53-55,共3页
提出一种使用BroadcastDisks算法来分布位图索引的空中索引方法,根据数据项访问概率,使用位图作为数据广播的索引,减少了移动终端等待数据时保持激活状态的时间,达到节能的目的。
关键词 broadcast DISKS 位图索引 数据广播 访问概率 节能
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基于区块链的车联网跨域数据安全传输系统设计
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作者 陈晨 王斓凯 施佺 《现代电子技术》 北大核心 2025年第1期71-79,共9页
为有效应对车联网系统在数据传输过程中的安全问题,提出一种基于区块链的车联网跨域数据安全传输系统。该系统将车联网安全数据传输过程划分为注册、安全通信与数据共享三个关键环节。在注册阶段,车辆和路边单元需要通过可信机构完成注... 为有效应对车联网系统在数据传输过程中的安全问题,提出一种基于区块链的车联网跨域数据安全传输系统。该系统将车联网安全数据传输过程划分为注册、安全通信与数据共享三个关键环节。在注册阶段,车辆和路边单元需要通过可信机构完成注册,以确保其的身份合法性;在通信阶段,为了减少路边单元与车辆频繁认证,设计了跨域认证的方法,保障数据传输的可靠性和完整性,并引入假名来保护用户隐私;在共享阶段,文中设计了基于多线程遍历共享广播森林的事务广播算法,利用广度优先搜索思想建立广播森林,并使用多线程遍历进行数据事务广播传输。实验仿真结果显示,文中方案的签名计算成本减少70%,验证计算成本减少41%;其次,在ER模型下,相比使用Gossip协议进行事务数据传输,该方案中交通数据事务总时间降低了93%;在BA模型下降低了87%。 展开更多
关键词 区块链 车联网 身份认证 密钥协商 广播森林 数据安全传输系统
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Godson-T众核体系结构上的Broadcast性能优化 被引量:3
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作者 包尔固德 李伟生 +2 位作者 范东睿 杨扬 马啸宇 《计算机研究与发展》 EI CSCD 北大核心 2010年第3期524-531,共8页
Godson-T是中国科学院计算技术研究所计算机系统结构重点实验室先进微系统组正在研制开发的适合于超深亚微米工艺实现的大规模片上众核系统.Godson-T片上存储的单端口结构节省了芯片面积但制约了共享数据的读取效率.直接在Godson-T上实... Godson-T是中国科学院计算技术研究所计算机系统结构重点实验室先进微系统组正在研制开发的适合于超深亚微米工艺实现的大规模片上众核系统.Godson-T片上存储的单端口结构节省了芯片面积但制约了共享数据的读取效率.直接在Godson-T上实现传统的Broadcast算法需要大量的同步互斥开销,无法达到很好的性能提升.基于Godson-T体系结构,对数据共享的重要并行算法Broadcast进行优化,提高了Godson-T体系结构下的数据共读的效率.主要采取了以下3项技术:消除大规模的线程同步,建立源地址到目的地址的映射表和用汇编语言实现Broadcast的核心部分.优化后Broadcast在小核数为32时即可达到5.8倍加速比. 展开更多
关键词 Godson-T 众核 broadcast 同步 互斥 共读 映射表 加速比
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基于Android Broadcast的短信安全监听系统的设计和实现
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作者 刘环 《智能计算机与应用》 2016年第6期59-61,共3页
在手机终端应用软件和移动业务呈现出多样化发展的同时,针对手机短信进行后台监听与窃取的恶意软件也大量出现,已经对手机信息安全构成了严重的威胁。从Android系统的Broadcast运行机制入手,设计一个具有捕获第三方恶意软件劫取短信行... 在手机终端应用软件和移动业务呈现出多样化发展的同时,针对手机短信进行后台监听与窃取的恶意软件也大量出现,已经对手机信息安全构成了严重的威胁。从Android系统的Broadcast运行机制入手,设计一个具有捕获第三方恶意软件劫取短信行为的监测软件,全程对广播进行监听和行为捕获,终止短信被劫取、转发等恶意行为的发生。在经过测试试验后效果良好,可以有效地解决短信被泄露的问题。 展开更多
关键词 广播 监听 注册 调用
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New mixed broadcast scheduling approach using neural networks and graph coloring in wireless sensor network 被引量:5
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作者 Zhang Xizheng Wang Yaonan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第1期185-191,共7页
Due to the mutual interference and sharing of wireless links in TDMA wireless sensor networks, conflicts will occur when data messages are transmitting between nodes. The broadcast scheduling problem (BSP) is aimed ... Due to the mutual interference and sharing of wireless links in TDMA wireless sensor networks, conflicts will occur when data messages are transmitting between nodes. The broadcast scheduling problem (BSP) is aimed to schedule each node in different slot of fixed length frame at least once, and the objective of BSP is to seek for the optimal feasible solution, which has the shortest length of frame slots, as well as the maximum node transmission. A two-stage mixed algorithm based on a fuzzy Hopfield neural network is proposed to solve this BSP in wireless sensor network. In the first stage, a modified sequential vertex coloring algorithm is adopted to obtain a minimal TDMA frame length. In the second stage, the fuzzy Hopfleld network is utilized to maximize the channel utilization ratio. Experimental results, obtained from the running on three benchmark graphs, show that the algorithm can achieve better performance with shorter frame length and higher channel utilizing ratio than other exiting BSP solutions. 展开更多
关键词 wireless sensor network broadcast scheduling fuzzy Hopfield network graph coloring.
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Broadcasting with Controlled Redundancy and Improved Localization in Wireless Sensor Networks 被引量:2
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作者 Tarun Dubey Om Prakash Sahu 《Journal of Electronic Science and Technology》 CAS 2013年第4期404-407,共4页
Wireless sensor networks (WSNs) consist of sensor nodes that broadcast a message within a network. Efficient broadcasting is a key requirement in sensor networks and has been a focal point of research over the last ... Wireless sensor networks (WSNs) consist of sensor nodes that broadcast a message within a network. Efficient broadcasting is a key requirement in sensor networks and has been a focal point of research over the last few years. There are many challenging tasks in the network, including redundancy control and sensor node localization that mainly depend on broadcasting. In this paper, we propose a broadcasting algorithm to control redundancy and improve localization (BACRIL) in WSNs. The proposed algorithm incorporates the benefits of the gossip protocol for optimizing message broadcasting within the network. Simulation results show a controlled level of redundancy, which is up to 57.6% if the number of sensor nodes deployed in a 500 m×500 m area are increased from 50 to 500. 展开更多
关键词 broadcast GOSSIP LOCALIZATION nodedensity REDUNDANCY wireless sensor networks.
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