Study on Environmental Parameters and Wearing Electrocardiogram

Over the years, environmental changes have made people focus their attention on the quality of their surrounding areas and work environment. However, there are some dangerous substances in areas suitable for human survival and work. People often ignore harmful substances in the air (e.g., substances determined by temperature and humidity, carbon dioxide, and other harmful gases), resulting in physical problems. These substances are often too small to be observed and will severely jeopardize a human body that has been long fixed in the same place. Therefore, the purpose of this study is to assist humans in detecting the presence of hazardous substances in their living and work environments, and to improve such environments through sampling and inspection. Through this effort, humans can survive in a living and working space, and live and work in a comfortable environment. On the basis of the Arduino development edition, in this study, we transfer data to a cloud database through WiFi and combine the cloud database with the heart rate from an electrocardiogram to detect the human heart rate in the work environment to achieve 24 h real-time monitoring at home or in the workplace. By improving the flow field of the interior space, we can further reduce the indoor harmful substance level and optimize human life and work quality. For life and industrial hygiene safety consciousness awakening, in this study, we can promote human safety in the living and work environments by using a sensor to prevent potentially dangerous genetic lesions or derivatives of a disease. In addition, the scope of this study is not limited to the living space of people but extends to factories or other places with harmful substances. In a high-risk work environment, the equipment can be used to conduct risk preanalysis and detection in place of a human to achieve full assessment or environmental improvement, which eliminates the safety concerns of people in the environment.


Introduction
Over the years, environmental changes have made people focus their attention on the quality of their surrounding areas and work environment [Development of the core technology of mobile-assist robots for the elderly health via Artificial Intelligence and Internet of Things (project number: MOST 107-2221-E-032-047-)].However, there are some dangerous substances in areas suitable for human survival and work.People often ignore harmful substances in the air, resulting in physical problems.(3)(4)(5) The electrocardiogram is one of the most important indicators of heart health.It can achieve a certain diagnostic effect through a noninvasive method.
In a previous study, (6) monitoring the use of wireless sensor network (WSN) technology to collect air quality data was proposed and the high potential of such technology was discussed.
In the currernt study, we demostrated a monitoring and visualization approach to help big data play a role in the health and safety decisions of the shipping industry.We also identified other potential applications of WSN technology and the visualization of big data in the work environment, e.g., to monitor worker safety in high-risk industries and commodity quality in supply chain management.
In another previous study, (7) the variation of electrocardiography (ECG)'s low frequency/ high frequency (LF/HF) ratio was proposed.As shown in Fig. 1, the sympathetic nervous system plays an important role in thermal discomfort.Once sympathetic excitation is achieved, temperature regulation disturbs the heat of the human body.Given the difference in LF/ HF ratio between the comfort and discomfort levels shown in Fig. 2, the LF/HF ratio can be considered as a physiological indicator of the thermal comfort level of the human body, as shown in Fig. 3.
Heart rate variability (HRV) is proposed in Ref. 8 as the index of thermal comfort in an office environment.Unlike existing mechanisms, this approach will allow people to predict the physical response of thermal comfort to the surrounding heat, as shown in Fig. 4. Most of the existing methods of environmental parameter detection are fixed-point measurement, and real-time data uploading cannot be achieved.Therefore, we hope to combine the cloud database with a web platform, so that viewers can view real-time data of environmental parameters anywhere and anytime.In this paper, real-time sensing of the parameters in the environment is proposed, and the arrhythmia analysis of wearing ECG is conducted for the personnel in the environment to observe the effect of the parameters in the environment on the heart rhythm of the subject.It will be confirmed by experiments that the heart rhythm of people changes with temperature, humidity, and carbon dioxide (CO 2 ) level, from which physiological information and physiological conditions of people in the environment can be observed.1)(12)(13)(14)

Structure
The structure used in this study is illustrated in Fig. 5. Arduino real-time measured data will be uploaded to the cloud, the WebCam camera will be employed for 24 h of real-time monitoring, the HRV of the subjects will be measured with a heartbeat band, and the above data will be displayed on a phone via Bluetooth to verify whether people in the environment feel physically ill from changes in the environment.7)(18)(19)(20)

Introduction of hardware
For the hard equipment used in this study, we employ an Arduino D1 development board combined with a DHT22 temperature and humidity module, an MG811 CO 2 sensor

Server architecture and web page presentation
WampServer is a development environment for Windows Web consisting of Apache2, PHP, and MySQL database.PHP MyAdmin can be employed to manage the database, as shown in Fig. 9. PHP page syntax can be used to capture database data and display them on the web page, as shown in Fig. 10.

System flowchart
The measurement is started.The camera, Arduino development platform, and heartbeat band are simultaneously turned on and the camera records the status of the experiment.The Arduino development platfrom measures the environmental data and uploads it to PHP.In addition, the ECG is measured through the heart band, and the ECG data is collected by a mobile phone.After collecting environmental and physiological data, the correlation between environmental quality and physical health is analyzed, as shown in Fig. 11.

Correlation between PM2.5 and ECG
As shown in Fig. 12, the subject was cooking in an airtight kitchen.The PM2.5 and ECG were measured, and then their correlation was analyzed.In the morning experiment that started at 00:05, the cooking time was 00:10, cooking was done at 00:30, and the measurement ended at 00:33. Figure 13 shows the relationship of HRV with temperature and humidity.Figure 14 shows the correlation between HRV and PM2.5 of the subject.Figure 15 shows subjects' ECG.

Correlation between CO 2 and ECG
As shown in Fig. 16, the subjects first measured CO 2 and ECG in an airtight classroom.During the measurement, fans were added to improve air convection, as shown in Fig. 17.Finally, the correlation between CO 2 and ECG was analyzed.The experimental test lasted from 15:42 to 17:50, the measurement was started at 15:42, and the half-time was 16:50.Fans were added to improve the indoor flow field.Then, the measurement was started at 17:10 and then ended at 17:50.A total of six subjects were included.18 shows CO 2 changes in classroom.Figure 19 shows the relationship of HRV with temperature and humidity of subject 1. Figure 20 shows the relationship between HRV and CO 2 of subjects 1. Figure 21 shows the heart rate of subject 1.

Conclusion
In this study, we primarily developed a web platform that is capable of detecting substances in the environment in real time and uploading them to a cloud database, allowing people to wear a load ECG device to compare the changes and determine the correlation between the substances in the environment and ECG.Many different situations were studied to compare the HRV analysis charts of the substances in air, and it was found that many changes indeed affect the heart rhythm of people.
The effects of CO 2 and PM2.5 were found to be most obvious in many experiments.Some studies have also attempted to increase convection in air to reduce parameters that can affect the heart rhythm of the human body, and the electrocardiogram can sometimes slightly differ since people's behaviors might affect the changes in the electrocardiogram.Thus, these situations are also aspects to be further analyzed.The major contribution of this study is the introduction of an environmental sensor into a platform, introducing the real-time sensing of the human body to analyze the effects of environmental parameters on the human heart rhythm and achieving the convenience of real-time sensing using a wearable device.

Fig. 19 .
Fig. 19.(Color online) Relationship between HRV and temperature and humidity of subject 1.
Yang-Han Lee received his B.S., M.S., and Ph.D. degrees in electrical engineering from National Taiwan University, Taipei, in 1987, 1989, and 1991, respectively.He joined the Department of Electrical Engineering, Tamkang University, Taipei, in 1994 and now serves as a professor.His main research interests include artificial intelligence, internet of things, and wireless communication systems.Hsien-Wei Tseng received his B.S. degree in electrical engineering from National Kaohsiung University of Applied Sciences in 2002 and his Ph.D. degree in electrical engineering from Tamkang University in 2010.He joined the School of Mathematics and Information Engineering, Longyan University, Longyan, Fujian, China, in Aug. 2017 and now serves as a professor.His main research interests include system design and performance evaluation in IoT and wireless communication systems.Yu-De Liao received his B.S. degree in computer and communication engineering in 2011 from DE LIN Institute of Technology and his M.S. degree in electronic engineering in 2013 from Tamkang University.He is currently a Ph.D. student at the Department of Electrical Engineering, Tamkang University.His main research interests include internet of things and wireless communication systems.Ting-Wei Lin received his B.S. and M.S. degrees in Electrical Engineering from Tamkang University, Taipei, in 2013, and 2015, respectively.He is currently a Ph.D. student at the Department of Electrical and Computer Engineering, Tamkang University.His main research interests include artificial intelligence, internet of things, and embedded systems.Yi-Lun Chen received his B.S. and M.S. degrees in electrical engineering from Tamkang University, Taipei, in 2015 and 2017, respectively.He is currently a Ph.D student at the Department of Electrical and Computer Engineering, Tamkang University.His main research interests include artificial intelligence, internet of things, and embedded systems.