REPORT FOR ANALYTICAL CHEMISTS
Figure 5.
Effect on input variation on
cB Deadline time 3 Average input. 41 units/day 2 5 % limit on overtime
CAPACITY RATIO (K
No floater Vacation
50
RADIOACTIVE α & β SAMPLES MEASURED AUTOMATICALLY
work would be completed within one day without recourse to over time. T h e cost ratio would be 1.0. This fact indicates t h a t a reduction in input variation should reduce costs. Figure 5 shows the effect of re ducing t h e coefficient of variation (standard deviation divided by mean) of the input from 0.54 to 0.39. T h e reduction in the mini m u m cost ratio is from 1.164 to 1.130 or 3.4%. Unfortunately, it is difficult, and probably not de sirable, to control either the amount or the sequence of work being sub mitted for analysis. Hence, arti ficial means of handling input vari ation must be introduced. One such method is to use a floater. A floater serves to reduce wage costs in two ways: by acting as a damper on input variations and by reducing the amount of overtime needed t o meet any given deadline. Figure 6 shows t h a t a floater, used on a 5 0 % availability basis, will reduce the cost ratio from 1.164 to 1.130, almost the same effect as a 1 5 % reduction in variation. Proposed Operating System. From the above information relating wage costs to service time distribu tion, it was concluded t h a t it would be feasible to impose a relative deadline time of 3 on the laboratory and to raise the capacity ratio to about 1.05, which is somewhat above the optimum ratio of 0.95. In doing so, it was realized t h a t a cost ratio of about 1.15 would re sult. The estimated improvement
31 32 33 34 35 36 37 38 38 1 2
Ζ1 .1* Ν 0 .01 R 33 kN 2 .3 8 Ν 2 Λ7 Ν 3 6 .6 7 Β 2 .7 2 Ν
.6 7 Ν L •3 1 .7 2 Β 3 5 UN "5 Λ 7 Μ
Printed out information includes, sample number, time and code
T H E NEW BAIRD-ATOMIC Automatic Sample Changer — a major improvement over conventional mecha nisms. Automatically programs, counts and records 50 pre-coded samples. Accuracy far greater than manual counting techniques. Magazine loading saves time and eliminates inter mixing. Each sample may be pre-coded to any one of four programs: "N" (normal operation), "B" (background or weak sample count), "R" (reject), or "L" (return to loading position). Maximum count accuracy is assured by complete " 4 ^ " shielding of the sample in the detector. For further information on Automatic Sample Changer and other systems, request B-A Catalog A-2
Baird-Atomic, Inc. 3 3 U N I V E R S I T Y RD., C A M B R I D G E 3 8 , M A S S .
Instrumentation for Better Analysis
B A
Baircd Atomic
For further information, circle number 38 A on Readers' Service Card, page 103 A 38 A
*
ANALYTICAL CHEMISTRY
CAPACITY ^ A ~ l u i K
Figure 6 .
Effect o f F l o a t e r on C s
Deadline time. 3 Average input. 41 units/day 2 5 % limit on overtime Floater available 5 0 % of requirement Coef. of variation. 0.54 Vacation
