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71.
In summary, changes came slowly at first in the OR. The biggest inventory reduction came about a year after the effort had begun. It would seem that tackling obsolescence, standardizing products, etc. would give an initial "big chunk" savings, with small amounts coming later as inventories are lowered. What we expected did not occur, due to the inherent nature of practices and what was customarily being used. For example, previously, some equipment purchases were paid for by purchasing product, which resulted in long-term commitments and high supply costs. The OR at times seemed more like a process of managing change, not just supplies. FOCUS is a daily process. How many times can you afford to overlook this process? How often are the mistakes of the past repeated? In review, we suggest this simple outline: Follow-through (review each case from start to finish), Obsolescence (schedule inventories every six months), Control (achieve inventory management by adjusting PAR levels to needs), Utilization (utilize product/equipment with your control), and Standardization (standardize products and measure results). 相似文献
72.
P. Gigante 《Decisions in Economics and Finance》1990,13(1-2):147-161
Viene studiato il problema della determinazione della strategia riassicurativa ottima in caso di riassicurazione individuale proporzionale, secondo l'approccio media-varianza. In particolare si analizzano alcuni modelli semplificati nei quali si raggruppano le polizze di un portafoglio sulla base di certe caratteristiche di omogeneità; ciò consente di ridurre in maniera sensibile la complessità dei calcoli previsti nella procedura generale. Completano il lavoro considerazioni di carattere operativo.
Summary The optimal reinsurance strategy for the proportional reinsurance problem in a meanvariance framework is investigated. In order to simplify the algorithmic complexity, simple models based on the aggregation of portfolio policies are studied. Some operational remarks are added.相似文献
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H. P. Brown 《The Economic record》1964,40(92):576-579
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On the concept of optimum population 总被引:4,自引:0,他引:4
Dasgupta PS 《The Review of economic studies》1969,36(3):295-318
The economic welfare of a community is affected by policies that determine both the rate of capital accumulation and the rate of growth of population. The optimum size of population at any point is time will depend on the size of the existing capital stock and the optimum rate of savings will depend on the existing number of people. Consequently, in this sense, a population policy cannot be developed without a concurrent savings policy. The criterion of optimality that will be used is the ma ximization of the total discounted welfare of all generations from now to infinity. The problem will be to select that rate of savings and that size of population at every moment which will achieve this maximum welfare if, in fact, a maximum exists. An inquiry is made into the existence of an optimum policy under various circumstances. An attempt is made to evaluate the consequences of various ethical beliefs. 相似文献
78.
Sommers PM 《Applied economics》1980,12(2):195-207
The attempt was made to obtain an improved estimate of the economic value of birth control programs in developing countries. A medium sized econometric simulation model -- based on data covering a cross-section of 67 countries -- was constructed to investigate the implications to a developing economy of birth prevention. Fertility measures were included in the model as important endogenous variables in the economic process, and parameter values were supplied by formal estimation rather than expert judgment. A matrix of age-specific birth and survival rates was used. The model has sufficient detail to generate a complete age distribution for the population, yielding improved estimates of the value of birth control and other growth policies. Initial focus is on the construction of the model. This is followed by simulation of the system with simulated paths compared to observed paths for a few countries. Projections of real per capita output and other variables with and without the presence of a birth control program are presented. The size of the differential economic effect associated with lower fertility is examined for 17 sets of initial conditions corresponding to a selection of 17 developing countries. Comparisons of birth control with other forms of investment are made. 相似文献
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Seven computerprograms for non-linear regression or curve fitting problems are compared. The comparison of the programs, running in different computing centra, is restricted to the fit performance. Six model functions are fitted according to the least squares criterion to data series, arising from practical work. The special least squares minimization programs turned out to be better suited for these problems than general optimizing programs. 相似文献