Term
|
Definition
1)Visual acuity improves with increased luminance
2) Contrast sensitivity improves with increased luminance
3) Temporal sensitivity increases with increased luminance
4) Color discrimination improves with increased luminance |
|
|
Term
| Overcoming the effects of luminance |
|
Definition
1)Increase the size of the detail in the task
2)Increase the contrast in the task
3)Ensure that the detail can be foveated
4)Reduce the velocity of the task
4)Increase exposure duration |
|
|
Term
|
Definition
1)Use high frequency control gear for lights
-or-
2)Use multiple lights with different phases |
|
|
Term
|
Definition
1)Can reduce performance and cause discomfort
2)Avoid having sources of bright light within viewing range of tasks |
|
|
Term
|
Definition
1)Common in places that have large pieces of equipment
2)Provide local lighting
3)Ensure reflection of light into shadowed areas
4)Use large light sources |
|
|
Term
|
Definition
1)Computer "glare"
2)Avoid having bright light sources where they can reflect off of work material |
|
|
Term
|
Definition
1)Sound is measured in decibels which is in units relative to the value near the threshold of human hearing (I0=10^-12 watts/m^2)
2)Loudness is given by
10Log(I/I0) |
|
|
Term
|
Definition
decibel; Lp=10log(p/p0)
where p0=10^-12 |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| OSHA requires hearing protection |
|
Definition
|
|
Term
| Multiple noise sources can be combined and measured with this formula |
|
Definition
| 10log(10^(LA/10)+10^(LB/10)) |
|
|
Term
|
Definition
|
|
Term
| Work is okay at ____ HRMAX |
|
Definition
|
|
Term
| Peak heart rate is okay at ___ HRMAX |
|
Definition
|
|
Term
| Determine a person's ability to do work |
|
Definition
1)Estimated by maximum heart rate
2)the standard deviation of the prediction is 10 beats per min |
|
|
Term
| Heart rate of moderate exercise |
|
Definition
|
|
Term
| Heart Rate for untrained workers |
|
Definition
1)Use 33% of HRMAX
2)Also applies if work primarily requires the use of muscles in the upper body |
|
|
Term
|
Definition
| the benefit that could have been gained from an alternative use of the same resource |
|
|
Term
|
Definition
| The loss of potential gain from other alternatives when one alternative is chosen. |
|
|
Term
|
Definition
1)Present evidence that a system is considered a "best practice"
2)Demonstrate the expected return on investment (ROI) |
|
|
Term
|
Definition
1)Operating profit/capital employed
2)Example ROI- 60,000/500,000=12% ROI |
|
|
Term
|
Definition
1)Taguchi believed that the value loss is a quadratic function of quality (as you move away from target specification, loss went up as quadratic)
2)Loss at a point- L(x)=k*(x-t)^2
(k=loss coefficient, x=measured value, t=target value)
3)Average Loss of a sample set:
L=k*(s^2+(pm-t)^2)
(s=sample st dev pm=process mean)
Note: k is a scaling factor called the loss coefficient and is found by solving for k from a known loss |
|
|
Term
Cost loss function example:
1) We have a part which measures 3.5 with a tolerance of .1. Outside of that, the part is unacceptable and incurs a cost of $10. The loss coefficient can be determined as follows:
2) What is our loss on a part measuring $3.46? |
|
Definition
1)- $10=k(.1)^2
- k=10/(.1)^2=1000
2)- L=1000(3.46-3.5)^2 = $1.60 |
|
|
Term
Cost loss function example:
1) We have a part which measures 3.5 with a tolerance of .1. Outside of that, the part is unacceptable and incurs a cost of $10. The loss coefficient can be determined as follows:
2) What if this is reduced to a process mean of 3.51, s=.01? |
|
Definition
1)- $10=k(.1)^2
- k=10/(.1)^2=1000
2)L=1000(.01^2+(3.51-3.5)^2)=$.20 |
|
|
Term
|
Definition
|
|
Term
|
Definition
1)Determine and describe the method to be used
-If used, time is a "should take" time, training required in step 3
-If not, time is a "did take" time, training not required
2)Break up method into elements of work that are to be separately timed
3)Select a "typical" operator and (optionally) train them
4)Time each element and record the time
5)Repeat timing n times and compute stats
6)Apply rating (correction factors) |
|
|
Term
| Break up method into work elements |
|
Definition
1)Work elements should be expected to take longer than 2.4 seconds but less than a few minutes when using a stopwatch and live timing
2)Each work element should generally consist of a logical group of motion elements (i.e. Therblings)
3)There should be no time gap between work elements, and the start and end of each work element should be easily identifiable |
|
|
Term
| Time trials; Select operator |
|
Definition
1)an expert nor a novice will not be a good standard
2)adjustments will be needed is worker is not near average
3)performance of the worker should be assessed against a learning curve to ensure training is sufficient
4)when performance is sufficiently close to minimum on learning curve, training is sufficient |
|
|
Term
|
Definition
n=[z/e]^2*q*(1-q)
where e=largest acceptable error |
|
|
Term
|
Definition
1)Multifactor rating system
2)Allowances |
|
|
Term
| Sound pressure calculation |
|
Definition
|
|
