Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collec...Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic conditions.The statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to dilution.The flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the river.The correlation between E.coli and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for E.coli to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor measurements.The correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land cover.Therefore,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.展开更多
It will show the feasibility of a Wireless Sensor Network (WSN) devoted to monitoring water basin, river, lake, and sea both on the surface and in depth. The swarm of floating probes can be programmed to periodically ...It will show the feasibility of a Wireless Sensor Network (WSN) devoted to monitoring water basin, river, lake, and sea both on the surface and in depth. The swarm of floating probes can be programmed to periodically sink some tens of meters below the surface, collecting data, characterizing water properties and then coming to the surface again. The life span of the probes may be assured by an on-board power supply or through batteries recharged by solar cells. The basic idea of the WSN is reported together with a detailed analysis of the operational constraints, the energy requirements, and the electronic and mechanical discussion.展开更多
To study the fluid dynamic response mechanism under the working condition of water injection well borehole,based on the microelement analysis of fluid mechanics and the classical theory of hydrodynamics,a fluid microe...To study the fluid dynamic response mechanism under the working condition of water injection well borehole,based on the microelement analysis of fluid mechanics and the classical theory of hydrodynamics,a fluid microelement pressure-flow rate relationship model is built to derive and solve the dynamic distribution of fluid pressure and flow rate in the space of well borehole.Combined with the production data of a typical deviated well in China,numerical simulations and analyses are carried out to analyze the dynamic distribution of wellbore pressure at different injection pressures and injection volumes,the delayed and attenuated characteristics of fluid transmission in tube,and the dynamic distribution of wellbore pressure amplitude under the fluctuation of wellhead pressure.The pressure loss along the wellbore has nothing to do with the absolute pressure,and the design of the coding and decoding scheme for wave code communication doesn’t need to consider the absolute pressure during injecting.When the injection pressure is constant,the higher the injection flow rate at the wellhead,the larger the pressure loss along the wellbore.The fluid wave signal delay amplitude mainly depends on the length of the wellbore.The smaller the tubing diameter,the larger the fluid wave signal attenuation amplitude.The higher the target wave code amplitude(differential pressure identification root mean square)generated at the same well depth,the greater the wellhead pressure wave amplitude required to overcome the wellbore pressure loss.展开更多
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
设计了一款轻便小巧的水质监测无人船,结合一体化水质监测电控系统进行水质温度、溶解氧质量浓度、氨氮质量浓度、pH的监测。硬件部分采用模块化结构设计,以Raspberry Pi 3B+作为主控模块,协同运行电源管理模块、数据采集模块、导航定...设计了一款轻便小巧的水质监测无人船,结合一体化水质监测电控系统进行水质温度、溶解氧质量浓度、氨氮质量浓度、pH的监测。硬件部分采用模块化结构设计,以Raspberry Pi 3B+作为主控模块,协同运行电源管理模块、数据采集模块、导航定位模块、避障模块、视觉采集模块、电机驱动模块、无线通信模块及岸基上位机。软件设计包括主程序、自主航行模式程序、遥控航行模式程序及无线通信模块程序的设计。将无人船放在城市湖面和河道进行实验,结果显示,5个固定监测点的监测参数在正常范围内,10个随机监测点的监测数据与专业仪器监测的数据相比,可决系数在0.94~0.99,验证了无人船运行的可行性以及监测数据的可靠性。展开更多
Wireless communications from air to fresh water are studied here. Our analysis relies on plane wave propagation mod-els. Specifically, the transmission loss and propagation loss of RF waves penetrating into fresh wate...Wireless communications from air to fresh water are studied here. Our analysis relies on plane wave propagation mod-els. Specifically, the transmission loss and propagation loss of RF waves penetrating into fresh water are calculated for various propagation depths. Even though RF wireless communications are not well suited for seawater due to its high attenuation, our paper illustrates that RF communications from air to fresh water are possible. Finally, this work de-rives the optimum frequencies, which provide minimum attenuation and maximum propagation depth, for RF commu-nications from air to fresh water.展开更多
基金supported by Center for Resiliency(CfR)at Lamar University(Grant No.22PSSO1).
文摘Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic conditions.The statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to dilution.The flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the river.The correlation between E.coli and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for E.coli to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor measurements.The correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land cover.Therefore,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.
文摘It will show the feasibility of a Wireless Sensor Network (WSN) devoted to monitoring water basin, river, lake, and sea both on the surface and in depth. The swarm of floating probes can be programmed to periodically sink some tens of meters below the surface, collecting data, characterizing water properties and then coming to the surface again. The life span of the probes may be assured by an on-board power supply or through batteries recharged by solar cells. The basic idea of the WSN is reported together with a detailed analysis of the operational constraints, the energy requirements, and the electronic and mechanical discussion.
基金Supported by the National Natural Science Foundation of China(52074345)CNPC Research and Technology Development Project(2021ZG12).
文摘To study the fluid dynamic response mechanism under the working condition of water injection well borehole,based on the microelement analysis of fluid mechanics and the classical theory of hydrodynamics,a fluid microelement pressure-flow rate relationship model is built to derive and solve the dynamic distribution of fluid pressure and flow rate in the space of well borehole.Combined with the production data of a typical deviated well in China,numerical simulations and analyses are carried out to analyze the dynamic distribution of wellbore pressure at different injection pressures and injection volumes,the delayed and attenuated characteristics of fluid transmission in tube,and the dynamic distribution of wellbore pressure amplitude under the fluctuation of wellhead pressure.The pressure loss along the wellbore has nothing to do with the absolute pressure,and the design of the coding and decoding scheme for wave code communication doesn’t need to consider the absolute pressure during injecting.When the injection pressure is constant,the higher the injection flow rate at the wellhead,the larger the pressure loss along the wellbore.The fluid wave signal delay amplitude mainly depends on the length of the wellbore.The smaller the tubing diameter,the larger the fluid wave signal attenuation amplitude.The higher the target wave code amplitude(differential pressure identification root mean square)generated at the same well depth,the greater the wellhead pressure wave amplitude required to overcome the wellbore pressure loss.
文摘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。
文摘设计了一款轻便小巧的水质监测无人船,结合一体化水质监测电控系统进行水质温度、溶解氧质量浓度、氨氮质量浓度、pH的监测。硬件部分采用模块化结构设计,以Raspberry Pi 3B+作为主控模块,协同运行电源管理模块、数据采集模块、导航定位模块、避障模块、视觉采集模块、电机驱动模块、无线通信模块及岸基上位机。软件设计包括主程序、自主航行模式程序、遥控航行模式程序及无线通信模块程序的设计。将无人船放在城市湖面和河道进行实验,结果显示,5个固定监测点的监测参数在正常范围内,10个随机监测点的监测数据与专业仪器监测的数据相比,可决系数在0.94~0.99,验证了无人船运行的可行性以及监测数据的可靠性。
文摘Wireless communications from air to fresh water are studied here. Our analysis relies on plane wave propagation mod-els. Specifically, the transmission loss and propagation loss of RF waves penetrating into fresh water are calculated for various propagation depths. Even though RF wireless communications are not well suited for seawater due to its high attenuation, our paper illustrates that RF communications from air to fresh water are possible. Finally, this work de-rives the optimum frequencies, which provide minimum attenuation and maximum propagation depth, for RF commu-nications from air to fresh water.
