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1.
A well-known problem of prediction in linear regression models is to find a confidence interval for the random value of the dependent variable when the values of the independent variables are given. Such a situation may arise in economic quality control models when the independent variables are costly inputs and the dependent variable is some measure of quality or production. In such a circumstance, an important control objective may be to find values for the inputs that will maximize the lower limit of the prediction confidence interval for a fixed budget, or alternatively, to minimize the cost of the inputs for a fixed lower limit of the confidence interval. In this paper, we shall show that global optima can be found using known algorithms. The special case of simple linear regression is discussed and an illustrative example is provided.  相似文献   
2.
In this note, we examine the algorithm of Drezner and Wesolowsky for locating a facility with maximin rectilinear distance to a given set of demand points. The concept of the closest-point constraint is introduced as a technique for increasing the efficiency of the algorithm. This potential increase in efficiency is demonstrated by an example.  相似文献   
3.
Without adding any solvent or water, we proposed a novel and green approach for the extraction of secondary metabolites from dried plant materials. This "solvent, water and vapor free" approach based on a simple principle involves the application of microwave irradiation and earth gravity to extract the essential oil from dried caraway seeds. Microwave dry-diffusion and gravity (MDG) has been compared with a conventional technique, hydrodistillation (HD), for the extraction of essential oil from dried caraway seeds. Essential oils isolated by MDG were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained by HD, but MDG was better than HD in terms of rapidity (45min versus 300min), energy saving, and cleanliness. The present apparatus permits fast and efficient extraction, reduces waste, avoids water and solvent consumption, and allows substantial energy savings.  相似文献   
4.
This paper presents a stochastic allocation model for a sequential financial problem involving the allocation of funds to uncertain future payments. It is shown that under certain conditions the optimal allocation policies are piece-wise linear with the budget available, and that there exists an intimate relationship between these policies and the myopic policies obtained from the solution of a sequence of single-payment problems. A numerical example is provided and, finally, certain technical and methodological issues associated with a chance constraint version of the problem are discussed.  相似文献   
5.
6.
Mehrez  Khaled 《Positivity》2018,22(1):341-356
Positivity - In this paper, we introduce the notion of the Weinstein positive definite functions and we state a version of Bochner’s theorem. Furthermore, we study the strictly Weinstein...  相似文献   
7.
In this paper our aim is to show some new inequalities of the Redheffer type for Bessel and modified Bessel functions of the first kind. The key tools in our proofs are some classical results on the monotonicity of quotients of differentiable functions as well as on the monotonicity of quotients of two power series. We also use some known results on the quotients of Bessel and modified Bessel functions of the first kind, and by using the monotonicity of the Dirichlet eta function we prove a sharp inequality for the tangent function. At the end of the paper a conjecture is stated, which may be of interest for further research.  相似文献   
8.
Purposes of these studies were to synthesize Zn(II) and Co(II) complexes of 3-nitro-4-hydroxybenzoic acid, determine their structures through X-ray crystallography, and obtain their anticonvulsant activities. Thermogravimetric, differential scanning calorimetry, impedance of aqueous solutions and magnetic properties analyses were also determined. Anticonvulsant and related activities of these complexes as well as Zn(II), Co(II), Ni(II) and Mg(II) (5-nitrosalicylato) complexes were determined by the National Institutes of Health, Antiepileptic Development Program. Results of these analyses are presented to document unique bonding features and physical properties of these compounds and their anticonvulsant activities. It is concluded that these compounds have chemical and physical properties that can be used to account for their anticonvulsant activities.  相似文献   
9.
This paper presents nonlinear dynamic modeling and control of flexible-link manipulators subjected to parametric excitation. The equations of motion are obtained using the Lagrangian-assumed modes method. Singular perturbation methodology is developed for the nonlinear time varying equations of motion to obtain a reduced-order set of equations. Control strategies, computed torque control and a composite control, based on the singular perturbation formulation developed, are utilized to reduce mechanical vibrations of the flexible-link and enable better tip positioning. Under the composite control technique, the effect of the value of perturbation parameter on the control signal is investigated. Numerical simulations supported by real-time experiments show that the singular-perturbation control methodology developed for the nonlinear time-varying system offers better system response over the computed torque control as the manipulator is commanded to follow a certain trajectory.  相似文献   
10.
Jack Brimberg  Abraham Mehrez 《TOP》2001,9(2):271-280
The location-allocation problem in its basic form assumes that the number of new facilities to be located is known and the capacities are unlimited. When the locations of the facilities and demand points (or customers) are restricted to the real line, the basic model may be solved efficiently by dynamic programming. In this note, we show that when the number of facilities and their capacities are included in the decision process, the problem may actually be easier to solve.  相似文献   
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