Biomedical subjects

X G Yuan

Publications and source records attributed to X G Yuan.

7 recordsLinked to original sources

PubMed2001

[Comparison study between biological vision and computer vision].

The development and bearing of biology vision in structure and mechanism were discussed, especially on the aspects including anatomical structure of biological vision, tentative classification of reception field, parallel processing of visual information, feedback and conformity effect of visual cortical, and so on. The new advance in the field was introduced through the study of the morphology of biological vision. Besides, comparison between biological vision and computer vision was made, and their similarities and differences were pointed out.

Aerospace Medicine↗

PubMed2001

[A study on physical characteristics of porous plates for water sublimator].

Objective. To investigate the development method of porous plate, the key part of water sublimator, and its main physical characteristics. Method. Technical parameters of porous plates used in water sublimator were analyzed. On the basis of this, porous plates made of different materials were developed by making use of sintered powder technology. A tester for testing the physical characteristics of porous plate was designed. All around physical characteristic tests for porous plates were conducted. Result. Main factors affecting performance of porous plates were tested. These provided basis for performance test of sublimator, established porous plate criterion and optimized porous plate. Conclusion. Porous plates developed by making use of sintered powder technology could meet requirements of performance of water sublimator.

Life Support Systems↗

PubMed2001

Human movement characteristics of target acquisition.

Objective. This paper deals with the problem of human movement characteristics of target acquisition. Method. A hypothetical model was posed by using experimental data. Result. The conception of final target size was put forward, an equation for calculating the movement time of target acquisition was obtained, and a new definition of index of difficulty was given. Conclusion. Analysis of experimental data showed that this equation could give a better description of target acquisition in a wide range.

Acceleration↗

PubMed2001

[Heat transfer analysis of liquid cooling garment used for extravehicular activity].

Brief description was given about the construction and function of the LCG (liquid cooling garment) used for EVA (extravehicular activity). The heat convection was analyzed between ventilating gas and LCG, the heat and mass transfer process was analyzed too, then a heat and mass transfer mathematical model of LCG was developed. Thermal physiological experimental study with human body wearing LVCG (liquid cooling and ventilation garment) used for EVA was carried out to verify this mathematical model. This study provided a basis for the design of liquid-cooling and ventilation system for the space suit.

Body Temperature↗

PubMed2001

[Geometrical dummy used for ergonomic evaluation on early stage cockpit conceptual design].

Objective. Basing on the need of cockpit ergonomic design, to set up a geometrical dummy. Method. Surface partition of the dummy, source of the curved face data, express of the curved face, degree of freedom of the human joint, coordinate system of the parts, position of the human segment centroid and weight of the human segment were cleared up first, then geometrical dummy was displayed with three-dimensional software. Result. The geometrical dummy could simulate some basic body movements and postures for ergonomic analysis. Conclusion. The geometrical dummy was suitable for present study and engineering design.

Anthropometry↗

PubMed1999

[Research progress of thermal control system for extravehicular activity space suit].

New research progress of thermal control system for oversea Extravehicular Activity (EVA) space suit is presented. Characteristics of several thermal control systems are analyzed in detail. Some research tendencies and problems are discussed, which are worthwhile to be specially noted. Finally, author's opinion about thermal control system in the future is put forward.

Aerospace Medicine↗

PubMed1999

[The present status and development of thermal control system of spacesuits for extravehicular activity].

With the extension of extravehicular activity (EVA) duration, the need for more effective thermal control of EVA spacesuits is required. The specific schemes investigated in heat sink system for EVA are discussed, including radiator, ice storage, metal hydride heat pump, phase-change storage/radiator and sublimator. The importance and requirements of automatic thermal control for EVA are also discussed. Existed automatic thermal control for EVA are reviewed. Prospects of further developments of thermal control of spacesuits for EVA are proposed.

Astronauts↗