Recent applications of theory of the firm under uncertainty

This paper provides a comprehensive synthesis and analysis of the current and recent empirical implementations of the theory of the firm under uncertainty, including multiple sources of uncertainty. In so doing, it identifies the major estimation obstacles and it offers the future empirical researcher ways to derive simple estimation procedures under multiple sources uncertainty.     

Coordinated control of distribution supply chains in the presence of fuzzy customer demand

This paper considers a single product inventory control in a Distribution Supply Chain (DSC). The DSC operates in the presence of uncertainty in customer demands. The demands are described by imprecise linguistic expressions that are modelled by discrete fuzzy sets. Inventories at each facility within the DSC are replenished by applying periodic review policies with optimal order up-to-quantities. Fuzzy customer demands imply fuzziness in inventory positions at the end of review intervals and in incurred relevant costs per unit time interval. The determination of the minimum of defuzzified total cost of the DSC is a complex problem which is solved by applying decomposition; the original problem is decomposed into a number of simpler independent optimisation subproblems, where each retailer and the warehouse determine their optimum periodic reviews and order up-to-quantities. An iterative coordination mechanism is proposed for changing the review periods and order up-to-quantities for each retailer and the warehouse in such a way that all parties within the DSC are satisfied with respect to total incurred costs per unit time interval. Coordination is performed by introducing fuzzy constraints on review periods and fuzzy tolerances on retailers and warehouse costs in local optimisation subproblems.     

Simulated annealing in the presence of noise

In many practical optimization problems, evaluation of a solution is subject to noise, e.g., due to stochastic simulations or measuring errors. Therefore, heuristics are needed that are capable of handling such noise. This paper first reviews the state-of-the-art in applying simulated annealing to noisy optimization problems. Then, two new algorithmic variants are proposed: an improved version of stochastic annealing that allows for arbitrary annealing schedules, and a new approach called simulated annealing in noisy environments (SANE). The latter integrates ideas from statistical sequential selection in order to reduce the number of samples required for making an acceptance decision with sufficient statistical confidence. Finally, SANE is shown to significantly outperform other state-of-the-art simulated annealing techniques on a stochastic travelling salesperson problem.     

Pressurised liquid extraction and quantification of fat-oil in bread and derivatives products

A pressurised liquid extraction (PLE) method for extraction and quantification of total fat and oil in bread and derivatives products has been proposed. Parameters implied in the extraction process; such us temperature, static time, number of extraction cycles, purge time and flush volume; have been optimised using a formal methodology based on statistical experimental design in order to obtain the best results. Moreover, this method has been validated using homemade bread elaborated in the laboratory which contained 9.64 g of olive oil in 100 g dry weight. The production and use of an “ad hoc” in-house reference material is just one of the most relevant aspects of this study. The uncertainty estimation has been carried out taking into account all the uncertainty components of the process and it was stated as 4.2%. Finally, the proposed method has been applied to six different Spanish bread derivatives products with different olive oil contents (5-20%) to determine the fat content.     

Uncertainty of measurement for summed masses: application to controlled substances

Because sentences for drug possession depend on the mass of the seized drug, testing laboratories must often determine the summed mass of numerous items submitted under a single case. One common practice for this purpose is to continue analyzing and weighing samples until a legal threshold is passed, at which point it is important to inform the court whether the summed mass is significantly above the threshold, or only marginally so. This paper develops a means for estimating the uncertainty of the summed mass for the common situation where the readability, d, of the balance dominates the uncertainty. It is seen that for all sample sizes the uncertainty, UM, is given by the remarkable simple expression UM = (d/2) × [N + SQRT(3N)] + N × CCE, where N is the number of items and CCE is the absolute value of the calibration check error. In most instances, this can be further simplified to UM = N × d.     

ICP-AES测定钛合金中铝、钼和锆的不确定度评定

对钛合金中铝、钼和锆含量测定过程中的不确定度来源进行了辨别,并在此基础上评定了分析结果的不确定度.测量不确定度主要来源于试样称量、标准溶液配制、校准曲线拟合、各种玻璃量器的使用及测量重复性.依据不确定度评定的步骤,计算得到了各分量标准不确定度及合成标准不确定度.     

直读光谱法测定不锈钢中铬的不确定度评定

利用光电直读光谱仪测定不锈钢中铬含量,对其在测量过程中不确定度产生的原因进行了分析,并对测量结果的不确定度进行了评定。     

Cloud and aerosol contributions to variation in shortwave surface irradiance over East Asia in July during 2001 and 2007

It is important to clarify the contributions of clouds and aerosols to the variation of surface shortwave irradiance (S) for climatological studies. This study examined the contributions of clouds and aerosols to the variation in S over East Asia (75-135°E, 20-55°N) in July during 2001 and 2007 using the index of potential radiative forcing (PRF) to characterize the temporal and geographical variations. After confirming the validity of PRF for multiyear analyses, we performed several temporal analyses of clouds and aerosols over the whole research domain. Changes in the geographical distribution, contribution histograms, and averaged values were studied. In agreement with previous studies that treated single-year cases, we confirmed that the magnitudes of the temporal changes in S variations due to clouds and aerosols were highly variable geographically. As for domain-averaged S variations, we did not observe defined trends for the research period. It was also found that the temporal variation between one parameter and its S variation was negatively correlated, from the point analyses at two locations. Based on these results, we concluded that PRF is a promising tool for research into long-term S variations. This kind of information will be quite valuable as basic data for use in climate modeling.     

Design and construction of multicrystal analyser detectors using Rowland circles: application to MAD26 at ALBA

A concept is given for describing multicrystal analyser detectors (MADs), as they are in use for synchrotron powder diffraction, on the basis of the Rowland circle construction. The Rowland circle is typically used to describe focusing geometries and can be adapted for the case of MADs working at a single energy as well as in a limited energy range. With this construction it is also possible to quantify and optimize the walk of the beam along non‐central crystals which is inevitable in certain detector designs. The results of this geometrical inspection are correlated with a real detector design that is implemented at the ALBA synchrotron facility in Spain. An error budget is given to estimate the influence and amount of tolerance of the manufacturing process.     

Unification theory of classical statistical uncertainty relation and quantum uncertainty relation and its applications

General classical statistical uncertainty relation is deduced and generalized to quantum uncertainty relation. We give a general unification theory of the classical statistical and quantum uncertainty relations, and prove that the classical limit of quantum mechanics is just classical statistical mechanics. It is shown that the classical limit of the general quantum uncertainty relation is the general classical uncertainty relation. Also, some specific applications show that the obtained theory is self-consistent and coincides with those from physical experiments.