scholarly journals The characteristics of particulate matter in different subway station environmental control systems in Beijing

2021 ◽  
Author(s):  
xinru Wang ◽  
liang xia ◽  
fei pei ◽  
zu wang ◽  
yiqiao liu ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Control System ◽  
Control Systems ◽  
Environmental Control ◽  
Strongly Correlated ◽  
Environment Control ◽  
Solid Foundation ◽  
Subway Stations ◽  
Pm2.5 And Pm10 ◽  
Screen System

Abstract The characteristics of inhalable particulate matter (PM2.5, PM10) in urban subway stations can have a major impact on passengers’ health. Existing research largely fails to focus on different environmental control systems and there are few studies focused on different pollution conditions. This study therefore focused on measuring and comparing the characteristics of PM2.5 and PM10 at subway stations with three control systems in Beijing different pollution conditions. Stations including three types of control system (open, closed and screen door) and outside were monitored and analyzed using a general linear model. The concentration of PM2.5 and PM10 at different locations, such as on platforms, in carriages and in working areas, was compared and analyzed under different external pollution conditions. The results show that at different environment control systems the characteristics of PM2.5 and PM10 are different. The concentrations of particles in closed system are generally higher than screen system at platform. While the pollution in carriage is heavier for open system than that of screen system. The PM2.5/PM10 ratio was 91%, 90% and 83.84% at closed, open and screen system, respectively. While, the PM2.5 and PM10 levels inside the stations were strongly correlated with the outdoor conditions regardless of the environmental control system. This is the first study to show the PM concentration characteristics for different subway environmental control systems. As such, it provides a solid foundation for air clean studies at subway stations with different control systems.

scholarly journals Real Time Control Systems of a Fighter Aircraft

2020 ◽  
Author(s):  
Asha Garg ◽  
Uma H. R. ◽  
Usha G. ◽  
Amitabh Saraf
Keyword(s):  
Control System ◽  
Control Systems ◽  
Real Time ◽  
Flight Control ◽  
Real Time Control ◽  
Fighter Aircraft ◽  
Redundancy Management ◽  
Time Control ◽  
Environment Control ◽  
Architecture And Design

Most modern fighter aircraft are multi-role by design and rely heavily on a number of systems that are computer controlled in real time for achieving the most optimal performance. This paper presents three important real time control systems designed for the Indian Light Combat Aircraft. These are the flight control system, the anti-skid brake control system and the environment control system. Design objectives for these systems along with a description of their various hardware elements, software architecture and design concepts have been presented here. All the systems house extremely critical functions during different phases of flight, and so are designed for high degrees of reliability and extremely low failure probabilities. The concepts adopted for redundancy management, failure identification and failure handling are also presented.

Piggery Environmental Control System Based on Wireless Sensor Networks with Energy Optimization

2014 ◽  
Vol 687-691 ◽  
pp. 865-868
Author(s):  
Wei Xing Zhu ◽  
Xiu Yi Mei ◽  
Yao Lu ◽  
Jian Fei Zhang
Keyword(s):  
Wireless Sensor Networks ◽  
Control System ◽  
Sensor Networks ◽  
Environmental Control ◽  
Energy Optimization ◽  
Sensor Nodes ◽  
Wireless Sensor ◽  
Control Center ◽  
Environment Control ◽  
Two Phases

According to the characteristics of piggery, such as complex environment, numerous control objects, complex wiring, a piggery environment control system based on wireless sensor networks was designed. This system consisted of the wireless network composed of various devices and sensors in piggery, the control center with ARM-LINUX and the remote control center. The energy of sensor nodes was offered by batteries in wireless sensor networks so that the power source was limited. In order to strengthen the node energy management, the LEACH algorithm was combined with AODV routing protocol, and a new optimization algorithm called LEACH-A was proposed in this paper. The wireless sensor networks execution process was divided into two phases, including cluster building and data transmission. In the two phases, the node residual energy was calculated by a weighted function and the cluster head role was changed by the size of remaining energy. NS-2 simulation results show that the proposed algorithm prolonged the lifetime of the nodes and the networks, and realized the energy optimization management.

scholarly journals Simulating faults in a Boeing 737-200 Environmental Control System using a thermodynamic model

2019 ◽  
Vol 10 (2) ◽  
Author(s):  
Manuel Esperon-Miguez ◽  
Ian K. Jennions ◽  
Ignacio Camacho Escobar ◽  
Nile Hanov
Keyword(s):  
Control System ◽  
Control Systems ◽  
Thermodynamic Model ◽  
Heat Exchangers ◽  
Environmental Control ◽  
Aircraft Cabin ◽  
Civil Aircraft ◽  
Key Driver ◽  
Condition Monitoring System ◽  
Using Data

The Environmental Control Systems ( ECS ), used to provide air to the aircraft cabin at the correct pressure and temperature, is a key driver of maintenance interruptions for military and civil aircraft. Fault detection is particularly difficult, due to the lack of instrumentation and the ability of the ECS’s control system to mask symptoms. Understanding how component degradation affects measurable thermodynamic parameters is key to developing a condition monitoring system for an ECS. This work focuses on the development of a thermodynamic model of a Boeing 737-200 ECS capable of simulating faults in three types of component: heat exchangers, valves, and water separators. The thermodynamic model has been validated using data collected on a ground-based instrumented B737-200 ECS. The results show how a thermodynamic model can be used to simulate the change of temperatures and pressures across the ECS when components degrade.

A High Temperature Decompression Chamber for Developing Aircraft Environmental Control Systems

1961 ◽  
Vol 65 (602) ◽  
pp. 111-126
Author(s):  
O. D. Furlong
Keyword(s):  
Control System ◽  
High Temperature ◽  
Control Systems ◽  
Environmental Control ◽  
Well Being ◽  
Second World War ◽  
Military Aircraft ◽  
World War ◽  
Humidity Control ◽  
Second World

The greatly increased performance of both civil and military aircraft since the Second World War has raised problems undreamt of at an earlier period and, from the simple measures originally introduced to improve pilot’s well-being, have sprung the complex installations which are now essential for human survival and comfort and to ensure the proper functioning of vital equipment carried in present day machines.The term “Environmental Control System” is used for convenience to cover collectively the various cabin and equipment bay, pressure, temperature and humidity control systems that are fitted.

scholarly journals A hybrid environment control system combining EMG and SSVEP signal based on brain-computer interface technology

2021 ◽  
Vol 3 (9) ◽  
Author(s):  
Mamunur Rashid ◽  
Bifta Sama Bari ◽  
Norizam Sulaiman ◽  
Mahfuzah Mustafa ◽  
Md Jahid Hasan ◽  
...  
Keyword(s):  
Control System ◽  
Real Time ◽  
Control Method ◽  
Environmental Control ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Neural Pathways ◽  
Common Spatial Pattern ◽  
Environment Control ◽  
Bci System

AbstractThe patients who are impaired with neurodegenerative disorders cannot command their muscles through the neural pathways. These patients are given an alternative from their neural path through Brain-Computer Interface (BCI) systems, which are the explicit use of brain impulses without any need for a computer's vocal muscle. Nowadays, the steady-state visual evoked potential (SSVEP) modality offers a robust communication pathway to introduce a non-invasive BCI. There are some crucial constituents, including window length of SSVEP response, the number of electrodes in the acquisition device and system accuracy, which are the critical performance components in any BCI system based on SSVEP signal. In this study, a real-time hybrid BCI system consists of SSVEP and EMG has been proposed for the environmental control system. The feature in terms of the common spatial pattern (CSP) has been extracted from four classes of SSVEP response, and extracted feature has been classified using K-nearest neighbors (k-NN) based classification algorithm. The obtained classification accuracy of eight participants was 97.41%. Finally, a control mechanism that aims to apply for the environmental control system has also been developed. The proposed system can identify 18 commands (i.e., 16 control commands using SSVEP and two commands using EMG). This result represents very encouraging performance to handle real-time SSVEP based BCI system consists of a small number of electrodes. The proposed framework can offer a convenient user interface and a reliable control method for realistic BCI technology.

scholarly journals Fuzzy Logic Based Environment Control of Operation Theatre

2021 ◽  
Vol 12 (1S) ◽  
pp. 220-232
Author(s):  
Sakshi Srivastav, Et. al.
Keyword(s):  
Fuzzy Logic ◽  
Control System ◽  
Fuzzy Logic Control ◽  
Fuzzy Logic Controller ◽  
Environmental Control ◽  
Environmental Parameters ◽  
Operation Theatre ◽  
Micro Particles ◽  
Logic Control ◽  
Environment Control

It is very critical and important to maintain the appropriate climatic conditions in the operation theatre. In paper, we present an approach to control total environmental conditions for the operation theatre. Generally for environmental control of operation theatre air conditioning system is installed. In operation theatre environmental parameters like humidity, temperature, oxygen and particles etc. have to be controlled precisely. All the environmental parameters are of nonlinear nature hence, difficult to control or model with the help of conventional control systems. Keeping in mind the complexity and nonlinearity of these parameters as fuzzy logic controller (FLC) for controlling all the environment of operation theatre has been designed. For this fuzzy logic control system temperature, micro particles, humidity & oxygen have been taken as input parameters and based on these parameters  speed of AC motor as well as the speed of exhaust motor are controlled. The control system is implemented with the help of different fuzzy rules and their membership functions derived from actual conditions. The performance of the system for control of operation theatre was studied and it has been observed that the result obtained with the fuzzy logic control system provides more effective and economical control. The fuzzy logic control system has been implemented using fuzzy Tech development tool.

Bayesian network method for fault diagnosis of civil aircraft environment control system

2019 ◽  
Vol 234 (5) ◽  
pp. 662-674
Author(s):  
Cui Liu ◽  
Jianzhong Sun ◽  
Fangyuan Wang ◽  
Shungang Ning ◽  
Guofan Xu
Keyword(s):  
Control System ◽  
Fault Diagnosis ◽  
Bayesian Network ◽  
Environmental Control ◽  
Fault Isolation ◽  
Commercial Aircraft ◽  
Extraction Technology ◽  
Data Set ◽  
Network Method ◽  
Environment Control

This paper addresses the issues of fault diagnosis of the environmental control system of a certain commercial aircraft model of which the environmental control system has a high failure rate in field and causes many unplanned maintenance events. Because of the complexity and reciprocal compensation mechanism of the environmental control system, it is difficult to carry out fault isolation timely once the failure occurred during aircraft turnaround time, which thus may cause flight delay or even cancelation. The original contribution of this work is to propose a Bayesian network–based fault diagnosis method for commercial aircraft environmental control system where a multi-information fusion mechanism is used to incorporate the system first principle, expert experience and condition monitoring data. It incorporates extraction technology of sensor feature parameters and the structural learning of Bayesian network to realize the effective diagnosis of multiple faults. A case study is conducted based on a data set from a commercial aircraft fleet. The results show that the fault isolation ratio of this method is greater than 89%. The proposed Bayesian fault diagnosis network method can be used as a troubleshooting tool for airline maintenance technicians in fault isolation of environmental control system, reducing the time spent on-line troubleshooting and aircraft downtime.

The Analysis of Tianjin Subway Environmental Control System

2012 ◽  
Vol 535-537 ◽  
pp. 2135-2138 ◽  
Author(s):  
Li Chang ◽  
Chen Hui Tang ◽  
Zheng Li
Keyword(s):  
Control System ◽  
Energy Consumption ◽  
Environmental Control ◽  
Distribution Characteristic ◽  
Two Systems ◽  
Subway System ◽  
Environment Control ◽  
Environment Simulation ◽  
The Difference ◽  
Different Characteristics

The paper takes Tianjin subway as an example, and use the Subway Environment Simulation (SES) program to establish subway system with platform screen doors or different characteristics of two systems to carry out the simulate computation in summer, transition season and winter of the two systems; by analyzing the difference between two environment control modes, get the chart of the temperature distribution characteristic. The table result showed that it has more advantages using closed system than PSD system in Tianjin by using the primary invests and saving energy consumption.

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