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Quality control of marine big data——a case study of real-time observation station data in Qingdao 被引量:6
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作者 QIAN Chengcheng LIU Aichao +4 位作者 HUANG Rui LIU Qingrong XU Wenkun ZHONG Shan YU Le 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第6期1983-1993,共11页
Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great s... Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great significance for exploiting and protecting the ocean.We used hourly mean wave height,temperature,and pressure real-time observation data taken in the Xiaomaidao station(in Qingdao,China)from June 1,2017,to May 31,2018,to explore the data quality using eight quality control methods,and to discriminate the most effective method for Xiaomaidao station.After using the eight quality control methods,the percentages of the mean wave height,temperature,and pressure data that passed the tests were 89.6%,88.3%,and 98.6%,respectively.With the marine disaster(wave alarm report)data,the values failed in the test mainly due to the influence of aging observation equipment and missing data transmissions.The mean wave height is often affected by dynamic marine disasters,so the continuity test method is not effective.The correlation test with other related parameters would be more useful for the mean wave height. 展开更多
关键词 quality control real-time STATION DATA MARINE BIG DATA Xiaomaidao STATION MARINE DISASTER
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RT-Notification: A Novel Real-Time Notification Protocol for Wireless Control in Fog Computing
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作者 Li Feng Jie Yang Huan Zhang 《China Communications》 SCIE CSCD 2017年第11期17-28,共12页
Fog computing is an emerging paradigm that has broad applications including storage, measurement and control. In this paper, we propose a novel real-time notification protocol called RT-Notification for wireless contr... Fog computing is an emerging paradigm that has broad applications including storage, measurement and control. In this paper, we propose a novel real-time notification protocol called RT-Notification for wireless control in fog computing. RT-Notification provides low-latency TDMA communication between an access point in Fog and a large number of portable monitoring devices equipped with sensor and actuator. RT-Notification differentiates two types of controls: urgent downlink actuator-oriented control and normal uplink access & scheduling control. Different from existing protocols, RT-Notification has two salient features:(i) support real-time notification of control frames, while not interrupting ongoing other transmissions, and(ii) support on-demand channel allocation for normal uplink access & scheduling control. RT-Notification can be implemented based on the commercial off-the-shelf 802.11 hardware. Our extensive simulations verify that RT-Notification is very effective in supporting the above two features. 展开更多
关键词 fog computing wireless control real-time NOTIFICATION
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Study on Rear-end Real-time Data Quality Control Method of Regional Automatic Weather Station
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作者 WANG Chao-qiu 《Meteorological and Environmental Research》 CAS 2011年第9期6-8,12,共4页
[Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional au... [Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional automatic weather station were introduced. Each element was treated with systematic quality control procedure. The existence of rear-end real time data of regional meteorological station in Guangxi was expounded. Combining with relevant elements and linear changes, improvement based on traditional quality control method was made. By dint of evaluation and relevant check of element, the quality of temperature and pressure was controlled. [Result] The method was optimized based on traditional quality control method, and it narrowed the effectiveness of real-time data quality control. The quality check of hourly precipitation applied relevant check of hourly minimum temperature, vertical consistency check of radar data, which can effectively improve the accuracy and credibility of hourly precipitation quality control. [Conclusion] The method was on trial for one year in the quality control of real-time data in the regional automatic meteorological station in Guangxi and had gained good outcome. 展开更多
关键词 Regional automatic stations real-time data quality control Method research China
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Quality Control System of Meteorological Real-time Data from Automatic Weather Stations in Shandong
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作者 ZHOU Xiao-tian CHU Xi WANG Hong 《Meteorological and Environmental Research》 2012年第1期48-50,共3页
The quality control system for meteorological real-time data from automatic weather stations in Shandong realized integration of communi- cation system and provincial quality control system, and an interaction platfor... The quality control system for meteorological real-time data from automatic weather stations in Shandong realized integration of communi- cation system and provincial quality control system, and an interaction platform which was mainly created by Web was set up. The system not only was fully guaranteed for the funning of basic business, also improved the reliability of the data. 展开更多
关键词 Automatic weather stations real-time data quality control China
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A Survey on Real-Time MAC Protocols in Wireless Sensor Networks
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作者 Zheng Teng Ki-Il Kim 《Communications and Network》 2010年第2期104-112,共9页
As wireless sensor network becomes pervasive, new requirements have been continuously emerged. How-ever, the most of research efforts in wireless sensor network are focused on energy problem since the nodes are usuall... As wireless sensor network becomes pervasive, new requirements have been continuously emerged. How-ever, the most of research efforts in wireless sensor network are focused on energy problem since the nodes are usually battery-powered. Among these requirements, real-time communication is one of the big research challenges in wireless sensor networks because most of query messages carry time information. To meet this requirement, recently several real-time medium access control protocols have been proposed for wireless sensor networks in the literature because waiting time to share medium on each node is one of main source for end-to-end delay. In this paper, we first introduce the specific requirement of wireless sensor real-time MAC protocol. Then, a collection of recent wireless sensor real-time MAC protocols are surveyed, classified, and described emphasizing their advantages and disadvantages whenever possible. Finally we present a dis-cussion about the challenges of current wireless sensor real-time MAC protocols in the literature, and show the conclusion in the end. 展开更多
关键词 wireless Sensor Networks MEDIUM ACCESS control (MAC) real-time
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A novel dynamic call admission control policy for wireless network 被引量:1
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作者 黄国盛 陈志刚 +2 位作者 李庆华 赵明 郭真 《Journal of Central South University》 SCIE EI CAS 2010年第1期110-116,共7页
To address the issue of resource scarcity in wireless communication, a novel dynamic call admission control scheme for wireless mobile network was proposed. The scheme established a reward computing model of call admi... To address the issue of resource scarcity in wireless communication, a novel dynamic call admission control scheme for wireless mobile network was proposed. The scheme established a reward computing model of call admission of wireless cell based on Markov decision process, dynamically optimized call admission process according to the principle of maximizing the average system rewards. Extensive simulations were conducted to examine the performance of the model by comparing with other policies in terms of new call blocking probability, handoff call dropping probability and resource utilization rate. Experimental results show that the proposed scheme can achieve better adaptability to changes in traffic conditions than existing protocols. Under high call traffic load, handoff call dropping probability and new call blocking probability can be reduced by about 8%, and resource utilization rate can be improved by 2%-6%. The proposed scheme can achieve high source utilization rate of about 85%. 展开更多
关键词 呼叫接纳控制 无线网络 控制策略 概率计算模型 马尔可夫决策过程 资源利用率 呼叫阻塞率 资源短缺问题
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A WIRELESS MULTIMEDIA TRANSMISSION CONTROL AlGORITHM OVER HETEROGENEOUS IP NETWORKS
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作者 Zhao Haitao Dong Yuning +1 位作者 Zhang Hui Li Yang 《Journal of Electronics(China)》 2010年第1期29-36,共8页
In this paper,an algorithm Wireless Multimedia Transmission Control(WMTC) is proposed for multimedia transmission control over wired-wireless networks.The relationship between packet length and packet loss rate in the... In this paper,an algorithm Wireless Multimedia Transmission Control(WMTC) is proposed for multimedia transmission control over wired-wireless networks.The relationship between packet length and packet loss rate in the Gilbert wireless error model is investigated.Furthermore,the algorithm can detect the nature of packet losses by sending large and small packets alternately,and control the sending rate of nodes.In addition,by means of updating factor K,this algorithm can adapt to the changes of network states quickly.Compared with previous algorithms,simulation results show that WMTC can both improve the networks throughput of multimedia transmissions and reduce the congestion loss rate in various situations. 展开更多
关键词 wireless IP networks quality of Service(QoS) Congestion control Random loss
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Transmission Considerations with QoS Support to Deliver Real-Time Distributed Speech Recognition Applications
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作者 Zhu Xiao-gang Zhu Hong-wen Rong Meng-tian 《Wuhan University Journal of Natural Sciences》 EI CAS 2002年第1期65-70,共6页
Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless... Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless links, some QoS mechanisms should be provided. We put forward a RTP/RSVP transmission scheme with DSR-specific payload and QoS parameters by modifying the present WAP protocol stack. The simulation result shows that this scheme will provide adequate network bandwidth to keep the real-time transport of DSR data over either wirelined or wireless channels. 展开更多
关键词 distributed speech recognition quality of service real-time transmission protocol resource reservation protocol wireless application protocol
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Unified Performance and Availability Model for Call Admission Control in Heterogeneous Wireless Networks
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作者 Ramesh Babu H. Siddamallaiah Gowrishankar Subramanian Piriyapatna S. Satyanarayana 《International Journal of Communications, Network and System Sciences》 2010年第4期406-412,共7页
The system capacity of wireless networks varies temporally. This may be due to the dynamic allocation of the channels and also the mobility of the users. The change in capacity will create greater impact on the system... The system capacity of wireless networks varies temporally. This may be due to the dynamic allocation of the channels and also the mobility of the users. The change in capacity will create greater impact on the system performance parameters. This variation of capacity particularly poses a greater challenge to the research community to ensure the Quality of Service (QoS) as it affects the call blocking probability which is one of the important QoS parameters. This paper proposes a performance model for call admission control and the availability model for a heterogeneous wireless network environment. The proposed model is able to handle three types of traffic considered for the study includes conversation traffic, interactive traffic and background traffic. The unified performance-availability model is developed using the Stochastic Area Networks (SAN). The performance of both analytical models and the SAN based performance-capacity models are verified by taking the call blocking probabilities for all the three types of traffics. 展开更多
关键词 CALL ADMISSION control CALL BLOCKING Probability Heterogeneous wireless NETWORKS Stochastic Activity NETWORKS quality of Service
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基于单片机技术的无人船湿地环境监测系统设计
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作者 黄涛 方青 孙庆业 《科技创新与应用》 2024年第9期50-55,60,共7页
针对当前湿地环境监测工作耗时耗力、安全系数低、成本高和采样难度大的问题,提出基于STC89C52RC和HC-12的无人船湿地环境监测系统。系统以STC89C52RC单片机为主控单元,使用便携式移动电源供电,通过导线连接由nRF905无线通信模块、HC-1... 针对当前湿地环境监测工作耗时耗力、安全系数低、成本高和采样难度大的问题,提出基于STC89C52RC和HC-12的无人船湿地环境监测系统。系统以STC89C52RC单片机为主控单元,使用便携式移动电源供电,通过导线连接由nRF905无线通信模块、HC-12无线通信模块、电机驱动系统、舵机驱动系统、水样采集系统、全球定位系统(global position system,GPS)和水质指标监测系统等构成的湿地环境监测无人船系统硬件部分,通过串口分别连接和烧写使用C#、keil软件制作上位机程序与nRF905单片机驱动程序,实现计算机通过串口通信方式完成单片机之间的无线通信和AT指令集的收发,从而达成计算机远距离实时遥控无人船进行定点水样采集与pH、浊度、温度指标监测的目的。野外实验结果证明,系统运行稳定,且水质指标测定结果精准。 展开更多
关键词 无线遥控 水样采集 水质指标监测 无人船 环境监测
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无线节点状态QC与资料品质关系研究与应用
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作者 田新琦 蔡存军 +2 位作者 瞿维迎 孟祥顺 路交通 《石油物探》 CSCD 北大核心 2024年第4期735-745,共11页
随着高密度地震采集技术的发展,采集排列片越来越大,用于接收的无线采集节点设备数量也随之成倍增加,基于WiFi和蓝牙的节点状态质控方法已无法满足每日地震数据采集前完成节点状态质控的要求。为此,引入了一种基于LoRa通信技术及LoRaWA... 随着高密度地震采集技术的发展,采集排列片越来越大,用于接收的无线采集节点设备数量也随之成倍增加,基于WiFi和蓝牙的节点状态质控方法已无法满足每日地震数据采集前完成节点状态质控的要求。为此,引入了一种基于LoRa通信技术及LoRaWAN通信协议的质控方法,并且借助无人机搭载LoRa网关,实现对节点状态的近实时质控。通过分析昆腾节点HyperQ质控数据,确定了节点异常状态出现频率最高的阻尼、自然频率和灵敏度3项基本信息,探讨了节点状态质控数据与地震数据之间的关系,提出了复杂作业区节点更换的指导原则,认为在无线节点地震数据采集过程中,应当综合应用节点状态质控方法和地震数据质控方法共同监控地震数据的采集质量。在南美地区X工区沼泽区地震数据采集项目中,基于节点更换原则,应用综合节点质控方法,在成本可控的前提下,保证了沼泽区单炮采集数据质量,使得采集质量指标为A级的单炮比例提高了9.72%,满足了质控要求,且新采集资料品质得到大幅提升。 展开更多
关键词 无线节点采集 LoRa技术 HyperQ质控技术 地震数据属性评价 单炮采集质量指标
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Theory on real-time control of construction quality and progress and its application to high arc dam 被引量:18
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作者 ZHONG DengHua1, REN BingYu1, LI MingChao1, WU BinPing1 & LI MingChuan2 1 Department of Hydraulic and Hydroelectric Engineering, School of Civil Engineering, Tianjin University, Tianjin 300072, China 2 Ertan Hydropower Development Company, Ltd., Chengdu 610051, China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第10期2611-2618,共8页
A complete scheme for solving the key scientific problems associated with high-standard,high-intensity continuous construction of high arch dams was presented. First,based on a coupling analysis of construction system... A complete scheme for solving the key scientific problems associated with high-standard,high-intensity continuous construction of high arch dams was presented. First,based on a coupling analysis of construction system decomposition and coordination for a high arc dam,a mathematical model for real-time control of construction quality and progress that considers complex constraints was developed. Second,a method of progress control was proposed based on a dynamic simulation. Third,a dynamic quality control mechanism was established based on construction information collected using a PDA. Fourth,a system for integrating collected information,progress simulation and quality control analyses under a network environment was developed. Finally,these methods were applied to a practical project to show that each aspect of a construction process can be managed effectively and that real-time monitoring and feedback control can be realized. Our methods provide new theoretical principles and technical measures for quality and progress control in the high arc dam construction process. 展开更多
关键词 CONSTRUCTION quality CONSTRUCTION PROGRESS dynamic simulation real-time control network HIGH ARC DAM
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Class of Service Support Layer for Wireless Mesh Networks
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作者 Jukka SUHONEN Timo D. HAMALAINEN Marko HANNIKAINEN 《International Journal of Communications, Network and System Sciences》 2010年第2期140-151,共12页
This paper presents an add-on Class of Service (CoS) layer for wireless mesh networks. The proposed protocol is applicable for contention-based MACs and is therefore compatible with most of the Wireless Local Area Net... This paper presents an add-on Class of Service (CoS) layer for wireless mesh networks. The proposed protocol is applicable for contention-based MACs and is therefore compatible with most of the Wireless Local Area Network (WLAN) and Wireless Sensor Network (WSN) protocols. The protocol has a locally centralized control for managing data flows, which either reserve a fixed bandwidth or are weighted by fair scheduling. The protocol reduces transmission collisions, thus improving the overall throughput. IEEE 802.11 adhoc WLAN has been taken as a platform for simulations and prototyping for evaluating the protocol performance. Network Simulator Version 2 (NS2) simulations show that the CoS protocol efficiently differentiates bandwidth, supports bandwidth reservations, and reaches less than 10 ms transfer delay on IEEE 802.11b WLAN. Testing with a full prototype implementation verified the performance of the protocol. 展开更多
关键词 wireless LAN wireless Sensor Network SCHEDULING TRAFFIC control (Communication) quality of Service
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An IEEE 802.15.4 Based Adaptive Communication Protocol in Wireless Sensor Network: Application to Monitoring the Elderly at Home
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作者 Juan Lu Adrien Van Den Bossche Eric Campo 《Wireless Sensor Network》 2014年第9期192-204,共13页
Monitoring behaviour of the elderly and the disabled living alone has become a major public health problem in our modern societies. Among the various scientific aspects involved in the home monitoring field, we are in... Monitoring behaviour of the elderly and the disabled living alone has become a major public health problem in our modern societies. Among the various scientific aspects involved in the home monitoring field, we are interested in the study and the proposal of a solution allowing distributed sensor nodes to communicate with each other in an optimal way adapted to the specific application constraints. More precisely, we want to build a wireless network that consists of several short range sensor nodes exchanging data between them according to a communication protocol at MAC (Medium Access Control) level. This protocol must be able to optimize energy consumption, transmission time and loss of information. To achieve this objective, we have analyzed the advantages and the limitations of WSN (Wireless Sensor Network) technologies and communication protocols currently used in relation to the requirements of our application. Then we proposed a deterministic, adaptive and energy saving medium access method based on the IEEE 802.15.4 physical layer and a mesh topology. It ensures the message delivery time with strongly limited collision risk due to the spatial reuse of medium in the two-hop neighbourhood. This proposal was characterized by modelling and simulation using OPNET network simulator. Finally we implemented the proposed mechanisms on hardware devices and deployed a sensors network in real situation to verify the accuracy of the model and evaluate the proposal according to different test configurations. 展开更多
关键词 wireless Sensor Network Medium Access control quality of Service Energy SAVING Mesh TOPOLOGY IEEE 802.15.4 Indoor MONITORING APPLICATION
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基于移相控制的LCC-S无线电能传输系统最佳品质因数研究
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作者 曹艳 刘志珍 +1 位作者 丁冉 刘正强 《电力科学与技术学报》 CAS CSCD 北大核心 2023年第5期57-64,97,共9页
无线电能传输系统的传输效率受到包括接收端品质因数在内诸多因素的影响。为此提出一种确定并保持二次侧品质因数的最佳值以保持最大效率的控制模型。研究基于LCC-S(电感/电容/电容-串联)拓扑,首先分析了不同品质因数Q情况下系统传输效... 无线电能传输系统的传输效率受到包括接收端品质因数在内诸多因素的影响。为此提出一种确定并保持二次侧品质因数的最佳值以保持最大效率的控制模型。研究基于LCC-S(电感/电容/电容-串联)拓扑,首先分析了不同品质因数Q情况下系统传输效率与工作频率、耦合系数的关系,提出了一种确定接收线圈品质因数Q最佳值的有效方法;然后提出了一种降压电路控制策略,该控制策略采用移相调节的方式来调节接收端电压的相角,以确保系统始终在最大效率点上运行;最后仿真并搭建了无线充电实验平台,验证了所提出的确定接收端品质因数Q最佳值的方法的可行性,证明了接收端降压转换器控制策略的有效性。 展开更多
关键词 无线电能传输 品质因数 最佳传输效率 移相控制
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Real-time remote monitoring system for aquaculture water quality 被引量:3
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作者 Luo Hongpin Li Guanglin +2 位作者 Peng Weifeng Song Jie Bai Qiuwei 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2015年第6期136-143,共8页
A multi-parameters monitoring system based on wireless network was set up to achieve remote real-time monitoring of aquaculture water quality,in order to improve the quality of aquaculture products and solve such prob... A multi-parameters monitoring system based on wireless network was set up to achieve remote real-time monitoring of aquaculture water quality,in order to improve the quality of aquaculture products and solve such problems as being difficult in wiring and high costs in current monitoring system.In the system solar cells and lithium cells were used for power supply.The YCS-2000 dissolved oxygen sensor,pH electrode,Pt1000 temperature sensor and ammonia nitrogen sensor were used to monitor the parameters of aquaculture water quality;STM32F103 chip was used for data processing;Zigbee and GPRS modules were used for data transmission to the remote monitoring center,where the data were stored and displayed.The system was connected with aerator to realize automatic control of dissolved oxygen concentration.The test results showed high confidence level of data transmission with a packet loss rate of 0.43%.Therefore,the system could fulfill the real-time remote monitoring of aquaculture water quality and had great practical significance in reduction of labor intensity,improvement of quality of aquatic products and protection of water environment. 展开更多
关键词 AQUACULTURE water quality real-time monitoring wireless sensor network AERATOR
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Operational guidance for aeration and flow augmentation for the Chicago Area Waterway System—A case study
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作者 Charles S.Melching Jennifer Wasik +1 位作者 Ed Staudacher Thomas Minarik 《Water Science and Engineering》 EI CAS CSCD 2023年第4期345-358,共14页
The Chicago Area Waterway System(CAWS)is a 133.9 km branching network of navigable waterways controlled by hydraulic structures,in which the majority of the flow is treated wastewater effluent and there are periods of... The Chicago Area Waterway System(CAWS)is a 133.9 km branching network of navigable waterways controlled by hydraulic structures,in which the majority of the flow is treated wastewater effluent and there are periods of substantial combined sewer overflows.The CAWS comprises a network of effluent dominated streams.More stringent dissolved oxygen(DO)standards and a reduced flow augmentation allowance have been recently applied to the CAWS.Therefore,a carefully calibrated and verified one-dimensional flow and water quality model was applied to the CAWS to determine emission-based real-time control guidelines for the operation of flow augmentation and aeration stations.The goal of these guidelines was to attain DO standards at least 95%of the time.The“optimal”guidelines were tested for representative normal,dry,and wet years.The finally proposed guidelines were found in the simulations to attain the 95%target for nearly all locations in the CAWS for the three test years.The developed operational guidelines have been applied since 2018 and have shown improved attainment of the DO standards throughout the CAWS while at the same time achieving similar energy use at the aeration stations on the Calumet River system,greatly lowered energy use on the Chicago River system,and greatly lowered discretionary diversion from Lake Michigan,meeting the recently enacted lower amount of allowed annual discretionary diversion.This case study indicates that emission-based real-time control developed from a well calibrated model holds potential to help many receiving water bodies achieve high attainment of water quality standards. 展开更多
关键词 Water quality modeling Water quality management real-time control Stream aeration Flow augmentation Dissolved oxygen
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WiNG节点仪器应用简介
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作者 吴青松 佴小君 +1 位作者 刘都让 付淼星 《物探装备》 2023年第5期299-302,306,共5页
WiNG节点仪器是Sercel公司的第三代节点仪器产品,具有轻便、续航时间长、无线实时质控、数据下载与充电一体化、数据管理软件操作简单、桩号自动拟合、RFID标签等特点;其无线质控有近距离的点对点直连,用于获取详细的节点运行状态数据... WiNG节点仪器是Sercel公司的第三代节点仪器产品,具有轻便、续航时间长、无线实时质控、数据下载与充电一体化、数据管理软件操作简单、桩号自动拟合、RFID标签等特点;其无线质控有近距离的点对点直连,用于获取详细的节点运行状态数据、运行测试、查看噪音等,和通过接力回传实现远距离节点站状态结果信息获取。2022年底国内首次引进该节点仪器系统并在中石化山东某三维地震勘探工区实施了大规模应用,取得了良好的应用效果。本文结合实际应用介绍了WiNG节点仪器的功能特点。 展开更多
关键词 地震勘探 节点仪器 WING 远程无线实时质控
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基于无线传感网络的改碱暗管排盐监控系统 被引量:10
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作者 周利明 韦崇峰 +4 位作者 苑严伟 周强兵 赵博 张俊宁 汪凤珠 《农业工程学报》 EI CAS CSCD 北大核心 2018年第6期89-97,共9页
针对目前盐碱地暗管改碱技术应用过程中存在的有效评测数据缺乏、无法准确对实施效果进行科学评价的问题,设计了一种基于无线传感网络的改碱暗管排盐监控系统,以实现对管道内地下水的水质监测、流量统计以及蓄水池水位控制等。监测节点... 针对目前盐碱地暗管改碱技术应用过程中存在的有效评测数据缺乏、无法准确对实施效果进行科学评价的问题,设计了一种基于无线传感网络的改碱暗管排盐监控系统,以实现对管道内地下水的水质监测、流量统计以及蓄水池水位控制等。监测节点实时采集各路暗管的p H值、电导率和流量信息传输到中心节点,监控中心计算机通过RS232接口获取各采集信息并进行处理显示;同时,液位传感器实时获取蓄水池的水位信息并通过无线传输模块将水位信息发送至中心节点,中心计算机根据实际水位和设定水位信息进行控制决策,并通过中心节点向水位控制节点发送控制指令,实现蓄水池的水位远程自动控制。为验证系统整体性能,对监控系统开展了水位控制、传感器检测精度、通讯距离与丢包率试验测试。试验结果表明:系统p H值和电导率的平均测量误差分别为1.81%、1.89%,各节点的最大丢包率为2.6%,整体运行稳定,数据传输可靠,能够满足实际生产需要。该系统能够准确获取改碱暗管内的水质信息及迁移变化情况,为暗管改碱技术的效果评价提供有利的数据支撑。 展开更多
关键词 无线传感器网络 电导率 监测 暗管改碱 水质参数 液位控制
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基于收益率的IEEE 802.16自适应概率接纳控制算法 被引量:7
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作者 王兴建 胡爱群 黄玉划 《电子与信息学报》 EI CSCD 北大核心 2007年第3期711-715,共5页
接纳控制(AC)在宽带无线接入(BWA)服务质量(QoS)中起着非常重要的作用。针对无线城域网IEEE802.16复杂的QoS定义,该文提出了统一的基于收益率的自适应概率接纳控制算法UAC和简化计算的改进算法EUAC,并给出性能分析。仿真结果表明,自适... 接纳控制(AC)在宽带无线接入(BWA)服务质量(QoS)中起着非常重要的作用。针对无线城域网IEEE802.16复杂的QoS定义,该文提出了统一的基于收益率的自适应概率接纳控制算法UAC和简化计算的改进算法EUAC,并给出性能分析。仿真结果表明,自适应算法可以根据当前的资源和负载自适应地改变接纳策略,对不同收益率的业务流表现出明显且合理的区分。自适应算法还具有明显的吞吐量和收益优势,在保持高资源利用率的同时,合理地控制低收益率流,避免已接纳的高收益率流降级。 展开更多
关键词 无线网络 自适应接纳控制 服务质量 收益率
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