Personal Velocity

One of the more promising developments at present for the short film is the combining of three or more shorts to produce a film that can be marketed as a feature. A recent example of this is writer/director Rebecca Miller s well received first "feature," Personal Velocity (2002)—three short films of under 30 minutes each, which are unified by theme, rather than location or use of the same actors. Each main character is a woman on the verge of a major change in her relationship to the man she lives with, and to the world. 

Aside from the general thermal state of the body, a person may find the thermal environment unacceptable or intolerable if local influences on the body from asymmetric radiation, air velocities, vertical air temperature differences, or contact with hot or cold surfaces (floors, machinery, tools, etc.) are experienced. 

One of the most critical factors is draft. Many people at low activity levels (seated/standing) are very sensitive to air velocities, and therefore draft is a very common cause for occupant complaints in ventilated and air-conditioned spaces. Fluctuations of the air velocity have a significant influence on a person s sensation of draft. The fluctuations may be ex-... 

The three categories in Table 6.3 apply to spaces where persons are exposed to the same thermal environment. It is advantageous if some kind of individual control over the thermal environment can be established for each person in a space. Individual control of the local air temperature, mean radiant temperature, or air velocity may contribute to reducing the rather large differences between individual requirements and therefore provide fewer dissatisfied. 

TTie ability of the ventilation system to protect the worker efficiently can readily be determined by personal samples. The PIMEX method (see Chapter 12) can be used to determine the worker s exposure during various work phases. The capture efficiency as well as the supply air fraction can be measured using tracer gas techniques. Simple evaluation is carried out visually with smoke tube or pellet tests. Daily system evaluation is recommended using airflow or static pressure measurements at appropriate parts of the system. The air velocities, turbulence intensities, air temperature, mean radiant temperature, and air humidity should also be measured to provide an assessment ol thermal comfort. 

The main forms of this type of hood are shown in Figs. 10.100-10.102. The difference between this type of hood and workbenches is that for fume cupboards the auxiliary air is only a part of the total exhaust flow rate and the flow is not intended to cover the person standing in front of the exhaust opening. The differences between this type of hood and an air curtain are that the air curtain is thinner, has a higher velocity covering the whole opening, and... 

Many other combinations exist but will not be described here. In small cabins, for storage or work, it is possible to supply and exhaust air in a controlled way to have a defined climate. There are also special sluices, where air is used to rinse the clothes from settled contaminants before a person proceeds to the next, cleaner room. In this case, very high air velocities are used, which could cause discomfort to the person. The residence time for the person usually is less than a couple of minutes and the main objective is to clean the clothes (and sometimes the skin) and therefore the high velocities do not matter. 

Errors related to velocity measurement instruments have different origins depending on the measurement principle. The most important of these have been covered in previous sections. One common source of error for all instruments is the disturbance of the flow field by the sensor/meter or the person carrying out the measuring. The influence of the sensor in an open space is usually... 

Scales of sensation A simple numerical scale used to report the response of a person to temperature, humidity, air velocity, air purity, noise, light, taste, etc. 

Triebig G, Reichenbach TH, Flugel KA. 1978. [Biochemical examinations and measurements of the conduction velocity in persons chronically exposed to trichloroethylene.] Int Arch Occup Environ Health 42 31-40. (German)... 

Electrostatic Liquid velocity Surface charge Personal charge Rubbing of plastic or rubber Liquid spray Mist Water jetting Powder flow on plastic Water settling... 

Triebig G, Weitle D, Valentin H. 1984. Investigations on neurotoxicity of chemical substances at the workplace V. Determination of the motor and sensory nerve conduction velocity in persons occupationally exposed to lead. Int Arch Occup Environ Health 53 189-204. 

Clearance in the upper, or ciliated, region is governed by the rate of mucus transport along the airways. These rates have been measured in the human nose and in dogs, rats, and other species. Asmundsson and Kilbum, Hilding, and Iravani established that mucociliary clearance rates increase from the distal bronchi toward the trachea. Because bronchial openings retard mucus flow, bifurcations receive an accumulation of mucus and associated particles. The rate of mucus production and mucus thickness and velocity vary from one person to another. Thickness increases and velocity decreases greatly when some toxic elements are present in the airway. 

The nontrivial transformation rule of Eq. (2.231) for the Ito drift coefficient (or the drift velocity) is sometimes referred to as the Ito formula. Note that Eq. (2.166) is a special case of the Ito formula, as applied to a transformation from generalized coordinates to Cartesian bead coordinates. The method used above to derive Eq. (2.166) thus constitutes a poor person s derivation of the Ito formula, which is readily generalized to obtain the general transformation formula of Eq. (2.231). 

Each person should find the remaining parameters and physical property data for this material required to solve the three models [Eqs. (8.14), (8.19), and (8.20)] for the erosive wear of a coal slurry that is, each person will have three calculations to do and three erosion rates as a result. Assume that the test temperamre is 343°C, the slurry velocity is 100 m/s, and the angle of attack is 50°. 

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