Terahertz technology has its unique advantages in the field of biomedicine and is increasingly used in modern medical applications. In this study, to research the responding of biological tissues (cells or nerve nuclei) to various terahertz energy stimulation, an automatic terahertz energy control optical system is designed. The ray tracing simulation of the selfdesigned optical lens model is conducted and the results show that the system can achieve the focusing arrangement within 90 mm and control the strength of terahertz energy on image plane. In addition, an automatic control system with nanometer-level precision is designed using a stepper motor subdivision scheme to coordinate with the image plane (target point) energy and morphology adjustment. Then biomedical experiments based on this system are carried out. Through adjusting the system, terahertz intensity on cells is changed, so that the cells show various cell viabilities. The optimized experimental results show that the terahertz energy automatic control optical system designed in this study is qualified for terahertz energy irradiation research with biological cells.

With the development of artificial intelligence technology, virtual reality technology has been widely used in the medical and entertainment fields, as well as other fields. This study is supported by the 3D modeling platform in UE4 platform technology and designs a 3D pose model based on inertial sensors through blueprint language and C++ programming. It can vividly display changes in gait, as well as changes in angles and displacements of 12 parts such as the big and small legs and arms. It can be used to combine with the module of capturing motion which is based on inertial sensors to display the 3D posture of the human body in real-time and analyze the motion data. Each part of the model contains an independent coordinate system, which can analyze the angle and displacement changes of any part of the model. All joints of the model are interrelated, the motion data can be automatically calibrated and corrected, and errors measured by an inertial sensor can be compensated, so that each joint of the model will not separate from the whole model and there will not occur actions that against the human body’s structures, improving the accuracy of the data. The 3D pose model designed in this study can correct motion data in real time and display the human body’s motion posture, which has great application prospects in the field of gait analysis.

The ocean is one of the most extensive ecosystems on Earth and can absorb large amounts of carbon dioxide. Changes in seawater carbon dioxide concentrations are one of the most important factors affecting marine ecosystems. Excess carbon dioxide can lead to ocean acidification, threatening the stability of marine ecosystems and species diversity. Dissolved carbon dioxide detection in seawater has great scientific significance. Conducting online monitoring of seawater carbon dioxide can help to understand the health status of marine ecosystems and to protect marine ecosystems. Current seawater detection equipment is large and costly. This study designed a low-cost infrared carbon dioxide detection system based on molecular theory. Using the HITRAN database, the absorption spectra and coefficients of carbon dioxide molecules under different conditions were calculated and derived, and a wavelength of 2361 cm−1 was selected as the measurement channel for carbon dioxide. In addition, considering the interference effect of direct light, an infrared post-splitting method was proposed to eliminate the interference of light and improve the detection accuracy of the system. The system was designed for the online monitoring of carbon dioxide in seawater, including a peristaltic pump to accelerate gas–liquid separation, an optical path structure, and carbon dioxide concentration inversion. The experimental results showed that the standard deviation of the gas test is 3.05, the standard deviation of the seawater test is 6.04, and the error range is within 20 ppm. The system can be flexibly deployed and has good stability and portability, which can meet the needs of the online monitoring of seawater carbon dioxide concentration.