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Pattern of sleep and wakefulness, the so-called circadian rhythm, is aligned with the natural rhythm of the external environment, based on the 24-hour biological pattern. Discrepancy towards natural biological rhythm results primarily in insomnia, fatigue and, above all, a visible deterioration in safety and performance of everyday daily and business tasks. The humanoid and correct sleep and wakefulness rhythm is conditioned by exposure to the solar cycle of 24 hours and normally ensures the peak of work activity during the day or sleep cycle during the night and is generated by endogenous neurons in the suprachiasmatic nucleus within the anterior hypothalamus. As the conducted research shows, shift work of medical staff is an example of a phase deviation from the normal biological rhythm in a human being and has been found to significantly affect occupational physiology, performance and safety of work activity, and to a significant extent it can also take on chronic health pathological features. Desynchronization in the rhythm of sleep and wakefulness in relation to the solar day results in periodic insomnia and daily fatigue at a time when the phase of wakefulness and maximum performance should be at its peak, which can cause not only reduced work performance, but can also result in extremely harmful, and considering the type of workplace, possible catastrophic outcomes in case of errors during work activities, conditioned by neurological dysfunctions of employees who perform their work in a shift mode. [ABSTRACT FROM AUTHOR]

Determining the anthropometric measures and biological characteristics of the human body using the conventional method is complex and time-consuming. The introduction of new computer methods (SABALab) allows fast and precise determining of all the important body values in order to adapt the dimensions and forms of elements in the operating ambient system of the road motor vehicle to the driver. The process of motor vehicle driving is performed with the necessary control of sight. While driving a motor vehicle, the necessary visual capabilities are expressed by recognizing the complex structures of actions, identification of diverse forms, colours, and the speed and precision of reactions based on the visual observation. The motor vehicle control is carried out in space and requires extremely good driver's sight capabilities, decisive for the coordination of movements, speed of reaction, and precision of performance. The driver's workplace is of a confined type with small layout area and a sitting position of the body which is suitable for ergonomic and biomechanical design. Static and dynamic anthropometric values refer to the kinematic capabilities of the driver and important arrangement of operating elements of the cockpit allowing the necessary degree of vision control and operating activities during the participation in the traffic environment. [ABSTRACT FROM AUTHOR]

High purity micron and sub-micron scale nickel materials have been mass-produced by the nickel carbonyl process for many decades. The same technology is being explored for mass production of nano-scale nickel products. The paper presents an overview of nickel carbonyl technology suitable for mass production of nano-scale nickel powders with surface areas exceeding 100 m2/g, and various three-dimensional nickel based micro structures. The industrial processes are based on the homogeneous decomposition of carbonyl in the free space of a CVD reactor and on the heterogeneous decomposition of carbonyl on a variety of substrates, including polymer foams and carbon fibres.

A new biomechanical three-dimensional (3D) model for the human mandible based on computer-generated virtual model is proposed. Using maps obtained from the special kinds of photos of the face of the real subject, it is possible to attribute personality to the virtual character, while computer animation offers movements and characteristics within the confines of space and time of the virtual world. A simple two-dimensional model of the jaw cannot explain the biomechanics, where the muscular forces through occlusion and condylar surfaces are in the state of 3D equilibrium. In the model all forces are resolved into components according to a selected coordinate system. The muscular forces act on the jaw, along with the necessary force level for chewing as some kind of mandible balance, preventing dislocation and loading of nonarticular tissues. In the work is used new approach to computer-generated animation of virtual 3D characters (called "Body SABA"), using in one object package of minimal costs and easy for operation.

Ergonomic contribution to designing and modeling of sitting working place by use of a computer and computer programs have been presented in this work. The influences of modeling working places on regular posture of a man/woman during work have been reconsidered, so that consumption of energy and fatigue are brought down to a minimum. For that purpose a computer program has been made which with input data on various kinds of work, sex and height of a worker determines the optimal ergonomic parameters during the modeling of a sitting working place. By computer visualisation the values of angle of spine curving have been calculated, the manipulation angle of arms and legs for three anthropometric heights of workers (160 cm, 175 cm and 190 cm). The dimensions of manipulative body space have been established by computerised 3D anthropometric analysis of movement as for example, reach of arms, legs, head, back etc positions. In this process the dimensions of machine and working space surrounding it in respect to optimal utilisation have been put in accordance with the anthropometric size of a man/woman.

In this work, 3D visualization of a work place by means of a computer-made 3D-machine model and computer animation of a worker have been performed. By visualization of 3D characters in inverse kinematic and dynamic relation with the operating part of a machine, the biomechanic characteristics of worker's body have been determined. The dimensions of a machine have been determined by an inspection of technical documentation as well as by direct measurements and recordings of the machine by camera. On the basis of measured body height of workers all relevant anthropometric measures have been determined by a computer program developed by the authors. By knowing the anthropometric measures, the vision fields and the scope zones while forming work places, exact postures of workers while performing technological procedures were determined. The minimal and maximal rotation angles and the translation of upper and lower arm which are basis for the analysis of worker burdening were analyzed. The dimensions of the seized space of a body are obtained by computer anthropometric analysis of movement, e.g. range of arms, position of legs, head, back. The influence of forming of a work place on correct postures of workers during work has been reconsidered and thus the consumption of energy and fatigue can be reduced to a minimum.