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Development and Application of Integrated Indicators for Assessing Healthcare Waste Management Systems in Kenyan Hospitals
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作者 Muriithi Jackson Githinji Paul Mwangi Njogu +1 位作者 Zipporah Nganga Mohamed Karama 《Open Journal of Applied Sciences》 2024年第4期1080-1120,共41页
Healthcare waste management (HCWM) is an important aspect of healthcare delivery globally because of its hazardous and infectious components that have potential for adverse health and environmental impacts. The paper ... Healthcare waste management (HCWM) is an important aspect of healthcare delivery globally because of its hazardous and infectious components that have potential for adverse health and environmental impacts. The paper introduces a set of indicators for assessing HCWM systems in hospitals. These indicators are: HCWM policies and standard operating procedures, management and oversight, logistics and budget support, training and occupational health and safety, and treatment, disposal and waste treatment equipment housing. By plotting a mark on a continuum which is defined as good and poor on the extremes and is connected with all other marks in a spoke arrangement, it’s possible to describe a baseline for HCWM in any specific hospital. This baseline can be used to improve awareness of the actors and policy-makers, compare the same hospital at a different point in time, to compare observations by different evaluators and to track improvements. Results suggest that in Kenya, the application of such indicators is useful for evaluating which priorities should be addressed to improve outcomes in HCWM systems. Systematic sampling technique was used to identify and collect data by use of observational checklist, interviews, visual verification and review of documents and a HCWM assessment tool. The objective is to suggest an integrated management tool as a method to identify prevailing problems with a HCWM system. The method can be replicated in other contexts worldwide, with a focus on the developing world. The integrated indicators focus on management of HCW and not its potential impact on human health and environment, an area recognized to be critical for future research. 展开更多
关键词 Developing Countries HCW Management indicators Management Tools
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The Impact of Health Information Technology on Hospital Performance: A Systematic Integrative Literature Review
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作者 Alisa Westerhof Cokky Hilhorst Willem Jan Bos 《Health》 2024年第4期257-279,共23页
Objective: To review, categorise, and synthesise findings from literature on health information technology (HIT) functionalities, HIT use, and the impact of HIT on hospital performance. Materials and Methods: We condu... Objective: To review, categorise, and synthesise findings from literature on health information technology (HIT) functionalities, HIT use, and the impact of HIT on hospital performance. Materials and Methods: We conducted a systematic integrative literature review based on a compre-hensive database search. To organise, categorise and synthesise the ex-isting literature, we adopted the affordance actualization theory. To align the literature with our research framework, we used four categories: 1) the functionalities of HIT and how these functionalities are measured;2) use and immediate outcomes of HIT functionalities;3) different perfor-mance indicators and how HIT functionalities affect them;and 4) what hospital characteristics influence the outcome of hospital performance. Results: Fifty-two studies were included. We identified four types of HIT. Only ten studies (19.2%) define the use of HIT by explicitly meas-uring the use rate of HIT. We identified five dimensions of hospital per-formance indicators. Every dimension showed mixed results;however, in general, HIT has a positive impact on mortality and patient readmis-sions. We found several hospital characteristics that may affect the rela-tionship between HIT and hospital-level outcomes. Discussion: Further efforts should focus on embedded research on HIT functionalities, use and effects of HIT implementations with more performance indicators and adjusted for hospital characteristics. Conclusion: The proposed framework could help hospitals and researchers make decisions regard-ing the functionalities, use and effects of HIT implementation in hospi-tals. Given our research outcomes, we suggest future research opportuni-ties to improve understanding of how HIT affects hospital performance. . 展开更多
关键词 Health Information Technology HIT Functionalities Hospital Performance indicators
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Progress in the Study of Laboratory Indicators Related to Acute Pancreatitis
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作者 Jiacheng Song Xiaoping Tan 《Journal of Biosciences and Medicines》 2024年第1期7-18,共12页
Acute pancreatitis (AP) is one of the more common gastrointestinal diseases in clinics and is characterized by rapid progression, many complications, and high mortality. When it develops into severe pancreatitis, its ... Acute pancreatitis (AP) is one of the more common gastrointestinal diseases in clinics and is characterized by rapid progression, many complications, and high mortality. When it develops into severe pancreatitis, its prognosis is poor. Therefore, early assessment of the degree of inflammatory response plays a crucial role in the treatment plan and prognosis of patients. More and more studies have shown that the levels of D-dimer (D-D), angiotensin-2 (Ang-2), phosphate, heparin-binding protein (HBP), retinol-binding protein-4 (RBP4), and osteoblastic protein (OPN) are closely related to the severity of acute pan-creatitis and can be used as effective indicators for early assessment of AP. In this paper, the research progress of the above indicators in assessing the severity of AP is summarized. 展开更多
关键词 Acute Pancreatitis Laboratory indicators PROGRESSION ASSESSMENT
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Evidence-Based Nursing Practice of Reducing Immune-Related Skin Toxicity of Tumor Patients Guided by Sensitive Indicators
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作者 Lingling Tang Qiong Wen 《Journal of Biosciences and Medicines》 2024年第4期210-215,共6页
Purpose research on nursing sensitive indicators in tumor Patients application effect in immune-related skin toxicity management. Method select our hospital April to June, 202360 cases patients with immune therapy set... Purpose research on nursing sensitive indicators in tumor Patients application effect in immune-related skin toxicity management. Method select our hospital April to June, 202360 cases patients with immune therapy settings as the control group. August-October, 2023 60 cases the patients treated with immune therapy were the experimental group. The control group adopted regular nursing methods, while the experimental group sensitive Indicators, evidence-based give preventive care. The social situation, psychological state, physical function, quality of life score, incidence of skin toxicity caused by immune checkpoint inhibitors, moderate and above of the two groups of patients were compared. Incidence of skin toxicity. Result: experience group SAS score, SDS score higher than the control group, the difference was statistically significant (P < 0.05);The incidence of skin toxic reactions caused by immune checkpoint inhibitors and the incidence of moderate and above skin toxic reactions in the experimental group are lower than those in the control group, and the difference is statistically significant (P < 0.05). Conclusion: sensitive indicator guidance evidence-based preventive care can reduce the degree of immune-related skin toxicity, improve the psychological state and quality of life of tumor patients treated with immune therapy and reduce the incidence of adverse reactions, improve nursing quality and patient satisfaction. 展开更多
关键词 Sensitive indicators Immune-Related Skin Toxicity Evidence-Based Practice Tumor
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Turbo Message Passing Based Burst Interference Cancellation for Data Detection in Massive MIMO-OFDM Systems
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作者 Wenjun Jiang Zhihao Ou +1 位作者 Xiaojun Yuan Li Wang 《China Communications》 SCIE CSCD 2024年第2期143-154,共12页
This paper investigates the fundamental data detection problem with burst interference in massive multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM) systems. In particular, burst inte... This paper investigates the fundamental data detection problem with burst interference in massive multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM) systems. In particular, burst interference may occur only on data symbols but not on pilot symbols, which means that interference information cannot be premeasured. To cancel the burst interference, we first revisit the uplink multi-user system and develop a matrixform system model, where the covariance pattern and the low-rank property of the interference matrix is discussed. Then, we propose a turbo message passing based burst interference cancellation(TMP-BIC) algorithm to solve the data detection problem, where the constellation information of target data is fully exploited to refine its estimate. Furthermore, in the TMP-BIC algorithm, we design one module to cope with the interference matrix by exploiting its lowrank property. Numerical results demonstrate that the proposed algorithm can effectively mitigate the adverse effects of burst interference and approach the interference-free bound. 展开更多
关键词 burst interference cancellation data detection massive multiple-input multiple-output(MIMO) message passing orthogonal frequency division multiplexing(ofDM)
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Study on Temperature Disaster Indicators of Passion Fruit in Southwest Fujian, China
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作者 Shiyun Mou Ping Shao +2 位作者 Yuchen Shi Shujie Yuan Lixin Su 《Journal of Geoscience and Environment Protection》 2024年第1期1-12,共12页
In China, meteorological forecasting relies on meteorological data obtained from regional and national stations. However, there were discrepancies between the data collected from the meteorological station at the pass... In China, meteorological forecasting relies on meteorological data obtained from regional and national stations. However, there were discrepancies between the data collected from the meteorological station at the passion fruit growing base and the data from regional and national stations. Consequently, the high and low temperature disaster indicators determined by the meteorological station at the passion fruit growing base cannot be applied to meteorological forecasting. To address this issue and facilitate the monitoring and early warning of high and low temperature disasters in passion fruit cultivation in Fujian, China, we used multi-source hourly temperature data (including the data from meteorological observation stations in passion fruit growing bases, the nearest regional stations, and national surface conventional meteorological observation stations) in three cities in southwestern Fujian (Longyan, Sanming, and Zhangzhou) spanning the years 2020 to 2022. By employing comprehensive statistical analysis methods (0.5 interval division and Cumulative frequency), we identified that passion fruit in southwestern Fujian was susceptible to high temperature disasters during the blooming-fruiting period, as well as low temperature disasters during the sprouting period. Consequently, we developed high and low temperature disaster indicators based on data from regional and national stations for different phenological periods of passion fruit in this region. 展开更多
关键词 Passion Fruit High Temperature Disaster Indicator Low Temperature Disaster Indicator Disaster Frequency Disaster Degree
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Polar codes based OFDM-PLC systems in the presence of impulsive noise
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作者 周玉 LI Yue +4 位作者 ZHAO Shuangshuang GAO Fan ZHOU Chao MU Zhuowen CHEN Rui 《High Technology Letters》 EI CAS 2024年第2期188-198,共11页
Power line communication(PLC)has the potential to become the preferred technique for providing broadband communication to homes and offices with advantage of eliminating the need for new wiring infrastructure and redu... Power line communication(PLC)has the potential to become the preferred technique for providing broadband communication to homes and offices with advantage of eliminating the need for new wiring infrastructure and reducing the cost.But it suffers from the impulsive noise because it introduces significant time variance into the power line channel.In this paper,a polar codes based orthogonal frequency division multiplexing(OFDM)PLC system is proposed to deal with the impulsive noise and thereby improve the transmission performance.Firstly,the impulsive noise is modelled with a multi-damped sine function by analyzing the time behavior of impulse events.Then the polar codes are used to combat the impulsive noise of PLC channel,and a low complexity bit-flipping decoding method based on CRC-aided successive cancellation list(CA-SCL)decoding algorithm is proposed.Simulations evaluate the proposed decoding algorithm and the results validate the suggested polar codes based OFDM-PLC scheme which can improve the BER performance of PLC with impulsive interference. 展开更多
关键词 orthogonal frequency division multiplexing(ofDM) polar code impulsivenoise power line communication(PLC) bit-flipping
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Development of Spectral Features for Monitoring Rice Bacterial Leaf Blight Disease Using Broad-Band Remote Sensing Systems
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作者 Jingcheng Zhang Xingjian Zhou +3 位作者 Dong Shen Qimeng Yu Lin Yuan Yingying Dong 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期745-762,共18页
As an important rice disease, rice bacterial leaf blight (RBLB, caused by the bacterium Xanthomonas oryzae pv.oryzae), has become widespread in east China in recent years. Significant losses in rice yield occurred as ... As an important rice disease, rice bacterial leaf blight (RBLB, caused by the bacterium Xanthomonas oryzae pv.oryzae), has become widespread in east China in recent years. Significant losses in rice yield occurred as a result ofthe disease’s epidemic, making it imperative to monitor RBLB at a large scale. With the development of remotesensing technology, the broad-band sensors equipped with red-edge channels over multiple spatial resolutionsoffer numerous available data for large-scale monitoring of rice diseases. However, RBLB is characterized by rapiddispersal under suitable conditions, making it difficult to track the disease at a regional scale with a single sensorin practice. Therefore, it is necessary to identify or construct features that are effective across different sensors formonitoring RBLB. To achieve this goal, the spectral response of RBLB was first analyzed based on the canopyhyperspectral data. Using the relative spectral response (RSR) functions of four representative satellite or UAVsensors (i.e., Sentinel-2, GF-6, Planet, and Rededge-M) and the hyperspectral data, the corresponding broad-bandspectral data was simulated. According to a thorough band combination and sensitivity analysis, two novel spectralindices for monitoring RBLB that can be effective across multiple sensors (i.e., RBBRI and RBBDI) weredeveloped. An optimal feature set that includes the two novel indices and a classical vegetation index was formed.The capability of such a feature set in monitoring RBLB was assessed via FLDA and SVM algorithms. The resultdemonstrated that both constructed novel indices exhibited high sensitivity to the disease across multiple sensors.Meanwhile, the feature set yielded an overall accuracy above 90% for all sensors, which indicates its cross-sensorgenerality in monitoring RBLB. The outcome of this research permits disease monitoring with different remotesensing data over a large scale. 展开更多
关键词 Rice bacterial leaf blight analysis of spectral response multispectral data simulation vegetation indices cross-sensor disease monitoring
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Optimization Management of Industrial Organizations Based on Performance Indicators
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作者 Anne Marie Chana Bernabé Batchakui Blaise Ndangang 《World Journal of Engineering and Technology》 2024年第1期185-199,共15页
This paper proposes an intelligent management system (IMS) to help managers in their delicate and tedious task of exploiting the plethora of data (indicators) contained in management dashboards. This system is based o... This paper proposes an intelligent management system (IMS) to help managers in their delicate and tedious task of exploiting the plethora of data (indicators) contained in management dashboards. This system is based on intelligent agents, ontologies and data mining. It is implemented by PASSI (Process for Agent Societies Specification and Implementation) methods for agent design and implementation, the Methodology for Knowledge Modeling and Hot-Winters for data prediction. Intelligent agents not only track indicators but also store the knowledge of managers within the company. Ontologies are used to manage the representation and presentation aspects of knowledge. Data mining makes it possible to: make the most of all available data;model the industrial process of data selection, exploration and modeling;and transform behaviors into predictive indicators. An instance of the IMS named SYGISS, currently in operation within a large brewery organization, allows us to observe very interesting results: the extraction of indicators is done in less than 5 minutes whereas manual extraction used to take 14 days;the generation of dashboards is instantaneous whereas it used to take 12 hours;the interpretation of indicators is instantaneous whereas it used to take a day;forecasts are possible and are done in less than 5 minutes whereas they did not exist with the old management. These important contributions help to optimize the management of this organization. 展开更多
关键词 Performance Indicator Intelligent Agent Data Mining Intelligent Management system Enterprise Management
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Monitoring of Sleep Indicators, Physical Activity, Pain, and Fatigue in Patients with Systemic Lupus Erythematosus and Relations among These Variables: A Pilot Study
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作者 Mitsuyo Inoue Kazuko Shiozawa +3 位作者 Ryosuke Yoshihara Yoshihito Shima Toru Hirano Kiyoko Makimoto 《Open Journal of Nursing》 2023年第1期22-44,共23页
Background: Poor sleep, fatigue, and pain are major health problems in patients with systemic lupus erythematosus (SLE). However, only cross-sectional surveys on these health outcomes have been conducted, and the asso... Background: Poor sleep, fatigue, and pain are major health problems in patients with systemic lupus erythematosus (SLE). However, only cross-sectional surveys on these health outcomes have been conducted, and the association between day-to-day fluctuations remains unknown. Objectives: We aimed to characterize daily fluctuations in sleep quality, physical activity, pain, and fatigue in patients with SLE. Method: Exploratory study with a cross-sectional design. Two rheumatology centers (a university hospital and a prefectural hospital) in Japan between September 2017 and May 2019. The sample size was set to 20. Demographic and clinical data were collected. Sleep and physical activity were measured with monitoring devices;pain and fatigue levels were recorded daily during the 4-week period. The Pittsburgh Sleep Quality Index, Short Form Health Survey-12, the Japanese version of the Lupus Patient Outcome, and SLE Disease Activity Index 2000 were collected at the start and end of the study. Descriptive statistics and coefficients of variation (CV) were tabulated to examine daily fluctuations. Pearson correlation coefficients were obtained for monitored variables. Results: The mean age was 43.7 ± 8.5 years, and the mean SLE duration was 16.0 ± 7.2 years. The mean moderate-to-vigorous physical activity (MVPA) duration was 7.8 ± 5.8 min/day, and the mean total sleep duration was 391.8 ± 65.3 min, with a mean sleep efficiency of 88.6% ± 6.1%. Daily fluctuations were high for leaving the bed frequency, MVPA duration, pain, and waking after sleep onset. Seventeen participants showed correlations between some of the variables, such as fatigue or longer MVPA duration and poorer sleep outcomes;longer sleep latency and increased frequency of leaving the bed;and higher physical activity and increased pain and fatigue. Conclusion: The quality of sleep and fatigue fluctuated daily, and correlations existed between these variables, as well as for pain and physical activity. The impact of MVPA duration on pain and fatigue is of concern as increased physical activity may worsen the quality of life patients with SLE. The monitoring of sleep and physical activity using the device seems feasible for SLE symptom management. 展开更多
关键词 Daily Fluctuation Sleep Indicator Physical Activity PAIN FATIGUE
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基于REOF的两种卫星降水产品(IMERG和MSWEP)在金沙江流域降水分区尺度精度评估
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作者 薄会娟 林青霞 +2 位作者 李璐 魏冲 龚成麒 《湖泊科学》 EI CAS CSCD 北大核心 2024年第2期620-633,共14页
高时空分辨率降水产品的精度评估是卫星降水用于水文气象干旱等研究的前提。本研究提出在降水分区尺度下评估IMERG和MSWEP两种卫星降水产品的精度,并与不分区尺度(即流域尺度)进行比较。首先采用旋转经验正交函数(REOF)对金沙江流域(JSB... 高时空分辨率降水产品的精度评估是卫星降水用于水文气象干旱等研究的前提。本研究提出在降水分区尺度下评估IMERG和MSWEP两种卫星降水产品的精度,并与不分区尺度(即流域尺度)进行比较。首先采用旋转经验正交函数(REOF)对金沙江流域(JSB)进行降水分区,通过贡献率得出8个分区较为适合。然后识别降水的空间分布特征,发现2种降水产品都可以很好地捕捉降水呈现出的从上游到下游逐渐增加的趋势。最后在日尺度、降水发生概率和极端降水探测能力3个方面对降水产品在分区尺度和不分区尺度的性能进行评估。结果表明,在日尺度上,MSWEP的精度在多数降水分区优于IMERG,被推荐5次(1、3、6、7和8区),集中在流域的中游。同时流域尺度也推荐MSWEP。在降水事件发生概率方面,MSWEP能再现不同等级降水强度的概率密度分布,但过高估计0.1~1 mm/d降水事件的发生概率;而IMERG过高估计小于0.1 mm/d降水事件的概率。在极端降水探测能力方面,流域尺度的KGE值都是正值,且IMERG优于MSWEP,但分区尺度上,KGE值在部分降水分区中存在负值,表明IMERG和MSWEP均不能很好地探测出该区的极端降水事件。本研究成果表明降水分区尺度是必需的,能够更加精细地评估降水产品。研究结果可为具有类似气候条件的卫星降水评估提供参考。 展开更多
关键词 降水分区 旋转经验正交函数 IMERG MSWEP 精度评估
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一种基于随机森林的OFDM系统自适应算法
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作者 王波 刘潇然 +2 位作者 熊俊 辜方林 张晓瀛 《信号处理》 CSCD 北大核心 2024年第6期1007-1018,共12页
针对动态变化的信道环境,自适应正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统可以对子载波间隔和循环前缀长度进行调整,以最大化系统的吞吐量。为了能够快速准确地找到OFDM系统在不同信道环境中的最优子载波间... 针对动态变化的信道环境,自适应正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统可以对子载波间隔和循环前缀长度进行调整,以最大化系统的吞吐量。为了能够快速准确地找到OFDM系统在不同信道环境中的最优子载波间隔和循环前缀长度取值,本文提出了基于随机森林的OFDM系统自适应算法。随机森林算法基于集成的思想,能够有效处理高维度数据,并且具有高效率、高准确率和强泛化能力等优势,可以在复杂的数据场景下进行有效的分类。通过提取通信过程中信噪比、用户移动速度、最大多普勒频率和均方根时延扩展等信道特征与OFDM系统的子载波间隔和循环前缀长度组成训练样本,利用随机森林算法创建了OFDM系统参数多分类模型。所提模型可以根据输入的信道特征,实现OFDM系统子载波间隔和循环前缀长度的自适应分配。同时,针对训练样本主要集中在少数几个系统参数类别的情况,利用合成少数类过采样技术对较少样本数的类别进行扩充,满足了随机森林算法对训练样本类别平衡化的需求,进一步提高了算法的分类准确率。相比传统的自适应算法,所提算法具有更高的分类准确率和模型泛化能力。分析和仿真结果表明,与子载波间隔和循环前缀长度固定的OFDM系统相比,本文所提出的自适应算法能够准确选择出最优的系统参数,可以有效地减轻信道中符号间干扰和子载波间干扰的影响,从而在整个信噪比范围上提供最大的平均频谱效率。基于随机森林的OFDM系统自适应算法能够动态地分配子载波间隔和循环前缀长度,增强OFDM系统的通信质量和抗干扰能力,实现在不同信道环境下的可靠传输。 展开更多
关键词 正交频分复用 合成少数类过采样技术 随机森林 自适应算法
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智能反射面辅助的OFDM系统稀疏信道估计研究
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作者 朱俊杰 彭玲 《计算机应用研究》 CSCD 北大核心 2024年第4期1159-1163,共5页
针对智能反射面(IRS)辅助的宽带正交频分复用(OFDM)系统的信道估计,当前大多数研究都是基于单符号全导频设置,且级联信道系数过多会导致导频开销较大。为此,提出了一种基于时域-角域块稀疏的两阶段信道估计方案。首先,通过分析信道在时... 针对智能反射面(IRS)辅助的宽带正交频分复用(OFDM)系统的信道估计,当前大多数研究都是基于单符号全导频设置,且级联信道系数过多会导致导频开销较大。为此,提出了一种基于时域-角域块稀疏的两阶段信道估计方案。首先,通过分析信道在时域和角域上存在的共同稀疏特性,将级联信道矩阵转换为时域-角域上的块稀疏表示,并将信道估计问题转换为块稀疏矩阵恢复问题。其次,考虑传输导频限制和时域-角域块稀疏特性,提出了一种两阶段稀疏信道估计方案对级联信道进行稀疏恢复。仿真结果表明,相比另外三种基准方案,该方案可以使用较少的导频获得更优的信道估计性能,有效减少了导频开销,且估计准确度更高。 展开更多
关键词 智能反射面 正交频分复用 信道估计 压缩感知
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OFDM系统中一种A-MMSE信道估计算法
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作者 叶文伟 《半导体光电》 CAS 北大核心 2024年第2期308-312,共5页
针对正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统中最小均方误差(Minimum Mean Squared Error,MMSE)信道估计算法误码率(BER)高的问题,提出一种平均最小均方误差(Averaged-Minimum Mean Squared Error,A-MMSE)... 针对正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统中最小均方误差(Minimum Mean Squared Error,MMSE)信道估计算法误码率(BER)高的问题,提出一种平均最小均方误差(Averaged-Minimum Mean Squared Error,A-MMSE)信道估计算法。该算法首先基于802.11n标准而构造了一种新的导频结构,收发两端分别进行降采样和过采样处理,利用已知训练序列和导频获得信道频域响应。仿真结果表明,所提出的A-MMSE信道估计算法与传统的MMSE算法相比,在BER为10^(-3)时,信噪比改善了约8dB。因而所提出的信道估计算法能明显改善系统的BER性能。 展开更多
关键词 正交频分复用系统 导频 最小均方误差 误码率
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DRFM干扰在OFDM新体制雷达中的研究
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作者 陈朝 王甲 +1 位作者 樊常力 钟旭洲 《雷达科学与技术》 北大核心 2024年第3期306-311,320,共7页
新体制雷达以正交频分复用(OFDM)数字调制方式作为雷达信号源,具有高频谱效率、高分辨能力等优点。本文首先介绍了新体制雷达系统的基本组成部分,主要包括OFDM信号源、发射模块、环境模块、接收模块和信号处理模块。其次介绍了数字射频... 新体制雷达以正交频分复用(OFDM)数字调制方式作为雷达信号源,具有高频谱效率、高分辨能力等优点。本文首先介绍了新体制雷达系统的基本组成部分,主要包括OFDM信号源、发射模块、环境模块、接收模块和信号处理模块。其次介绍了数字射频存储器(DRFM)干扰的主要组成部分以及工作原理,其中主要包括假目标干扰。最后将DRFM干扰与新体制雷达结合,在加干扰和不加干扰两种情况下对仿真目标进行测距和测速,结果验证了新体制雷达测量目标的准确性以及DRFM干扰的可行性。对新体制雷达及DRFM干扰研究具有参考意义。 展开更多
关键词 新体制雷达 正交频分复用 数字射频存储器 假目标
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基于扰动时空混沌的三维OFDM星座加密方案
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作者 赵耿 吴锐 +2 位作者 马英杰 黄思婕 董有恒 《计算机科学》 CSCD 北大核心 2024年第5期390-399,共10页
无线通信网络的迅猛发展使得传输信息量迅速增加,这对系统的传输效率和通信安全提出了更高的要求。为满足上述要求,提出了一种基于扰动时空混沌的三维OFDM星座加密方案。首先,设计了一种反馈元胞自动机,以提高元胞自动机的周期性和伪随... 无线通信网络的迅猛发展使得传输信息量迅速增加,这对系统的传输效率和通信安全提出了更高的要求。为满足上述要求,提出了一种基于扰动时空混沌的三维OFDM星座加密方案。首先,设计了一种反馈元胞自动机,以提高元胞自动机的周期性和伪随机性。将反馈元细胞自动机的迭代结果进行归一化后,作为扰动加入时空混沌系统中。通过分岔图、李亚普诺夫指数、回归映射分析和随机性测试,证明了添加该扰动的系统具有良好的混沌特性。其次,设计了一种新的三维16-ary星座图,将星座点之间的最小欧氏距离扩大了6.3%,并结合扰动的时空混沌系统实现了三维星座旋转的物理层调制加密。实验仿真结果表明,与其他三维16-ary星座映射旋转加密算法相比,该算法的误码率性能提高了约1 dB。此外,通过密钥空间、密钥灵敏度和统计攻击的安全分析,证明了其良好的安全性能。 展开更多
关键词 ofDM 三维映射 星座旋转 时空混沌系统 初等元胞自动机
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PSO算法下GP-周期随机共振的微弱OFDM信号检测
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作者 刘高辉 刘明阳 《微电子学与计算机》 2024年第3期81-89,共9页
为了解决传统随机共振系统在微弱正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)信号解调应用中存在的人工选择参数困难、解调效果差的问题,提出一种基于粒子群优化(Particle Swarm Optimization,PWO)算法的GP(Gaussia... 为了解决传统随机共振系统在微弱正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)信号解调应用中存在的人工选择参数困难、解调效果差的问题,提出一种基于粒子群优化(Particle Swarm Optimization,PWO)算法的GP(Gaussian Potential)-周期随机共振系统的微弱OFDM信号检测方法。该方法利用GP-周期随机系统对OFDM信号经正交变换后的两路高频信号分别进行随机共振,同时运用阻尼参数与信号频率之间的关系对两路信号进行降频处理,使得上下两路信号都能够发生随机共振;然后使用PWO算法对随机共振的系统参数进行优化处理,以使得上下两路信号达到最优的共振效果;最后,将上下两路共振之后的信号合成完成OFDM信号解调,得到最终的数字序列。本文探讨了优化前后GP-周期随机共振系统的共振效果,研究了优化前后GP-周期随机共振诱导下的OFDM系统星座图的聚集程度以及误码率情况,对比分析了经典双稳随机共振、经典三稳随机共振和所提模型对OFDM信号检测的影响。仿真结果表明:相比常用的传统随机共振模型,该方法用于OFDM信号检测的星座图中信号点的聚集程度更高,同时OFDM系统误码率在同样的信噪比下降低50%左右。 展开更多
关键词 GP-周期随机共振 信号检测 粒子群优化算法 正交频分复用 调整阻尼参数
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NC-OFDM雷达通信一体化设计
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作者 朵琳 刘毅 《陕西理工大学学报(自然科学版)》 2024年第1期56-64,共9页
雷达通信一体化有利于提高设备硬件资源利用率和频谱利用率,已成为近年来的研究热点。针对目前频谱资源稀缺的情况,结合认知无线电的概念,提出了基于非连续正交频分复用(NC-OFDM)的雷达通信一体化设计,对NC-OFDM雷达通信一体化信号测量... 雷达通信一体化有利于提高设备硬件资源利用率和频谱利用率,已成为近年来的研究热点。针对目前频谱资源稀缺的情况,结合认知无线电的概念,提出了基于非连续正交频分复用(NC-OFDM)的雷达通信一体化设计,对NC-OFDM雷达通信一体化信号测量目标特征进行了距离及速度的估计,并对基于NC-OFDM雷达通信一体化信号模糊函数、雷达成像的距离分辨率和方位分辨率、自相关性及误码率进行了分析,同时,选取互信息作为指标,利用优化算法进行波形设计。仿真结果表明,NC-OFDM雷达通信一体化信号具有较好的雷达探测性能和更为优良的无线通信性能。 展开更多
关键词 雷达通信一体化 认知无线电 非连续正交频分复用 雷达探测 无线通信
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GDS-MIMO-OFDM雷达通信一体化波形设计
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作者 赵忠凯 闫秋贞 《舰船电子对抗》 2024年第1期1-8,71,共9页
针对正交频分复用(OFDM)雷达通信一体化波形存在的通信速率较低、自相关旁瓣较高的问题,提出了一种基于Gold码扩频的多输入多输出-正交频分复用(MIMO-OFDM)雷达通信一体化波形。将MIMO-OFDM与扩频序列相结合,利用相关性较好的Gold码对... 针对正交频分复用(OFDM)雷达通信一体化波形存在的通信速率较低、自相关旁瓣较高的问题,提出了一种基于Gold码扩频的多输入多输出-正交频分复用(MIMO-OFDM)雷达通信一体化波形。将MIMO-OFDM与扩频序列相结合,利用相关性较好的Gold码对通信信息进行扩频,再与OFDM脉冲符号进行调制,进而设计出一种既能提高通信速率又能改善雷达性能的一体化波形。仿真实验证明,较相同仿真条件下的Gold-OFDM、脉冲压缩-正交频分复用(PC-OFDM)一体化波形而言,所设计的一体化波形的通信速率能够倍数提高且可以在不影响通信性能的前提下降低信号模糊函数的旁瓣,从而改善一体化系统的雷达性能。 展开更多
关键词 雷达通信一体化 多输入多输出-正交频分复用雷达 模糊函数 扩频
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深度学习辅助的5G OFDM系统的信道估计 被引量:1
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作者 王义元 常俊 +2 位作者 卢中奎 余福慧 魏家齐 《电讯技术》 北大核心 2024年第1期36-42,共7页
传统的信道估计算法难以满足5G系统中的高速率低时延的需求。针对该问题,将通信信道的时频响应视为二维图像,提出了一种基于图像恢复技术的信道估计方法。首先,设定参数产生基于5G新空口(New Radio,NR)标准的物理下行链路共享信道(Physi... 传统的信道估计算法难以满足5G系统中的高速率低时延的需求。针对该问题,将通信信道的时频响应视为二维图像,提出了一种基于图像恢复技术的信道估计方法。首先,设定参数产生基于5G新空口(New Radio,NR)标准的物理下行链路共享信道(Physical Downlink Shared Channel,PDSCH)的信道数据信息数据集,将所产生的信道矩阵看作二维图像;然后,构建基于卷积神经网络的图像恢复网络,并融入残差连接来提高网络的性能;最后,利用训练好的网络模型进行信道估计。仿真结果表明,与最小二乘算法(Least Square,LS)、实际信道估计(Practical Channel Estimation,PCE)和基于图像超分辨率ChannelNet网络相比,所提出的信道估计算法性能提升明显。 展开更多
关键词 5G 正交频分复用(ofDM) 信道估计 深度学习 卷积神经网络
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