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A generalization of Ascoli–Arzelá theorem in Banach spaces is established. Schauder's fixed point theorem is used to prove the existence of a solution for a boundary value problem of higher order. The authors’ results are obtained under, rather, general assumptions.

First, a generalization of Ascoli–Arzelá theorem in Banach spaces in Cⁿ is established. Second, this new generalization with Schauder's fixed point theorem to prove the existence of a solution for a boundary value problem of higher order is used. Finally, an illustrated example is given.

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In this work, a new generalization of Ascoli–Arzelá theorem in Banach spaces in Cⁿ is established. To the best of the authors’ knowledge, Ascoli–Arzelá theorem is given only in Banach spaces of continuous functions. In the second part, this new generalization with Schauder's fixed point theorem is used to prove the existence of a solution for a boundary value problem of higher order, where the derivatives appear in the non-linear terms.

I‐V characteristics of GaAs n‐i‐n structures are calculated by considering impact ionization of carriers. Impact ionization at reverse‐biased n‐i junction becomes a cause of steep current rise when an acceptor density in the i‐layer is high. It is shown that an optimum acceptor density exists to keep a good isolation. Photoconduction transients of GaAs n‐i‐n structures are also simulated, and are shown to be strongly affected by existence of n‐i junctions.

In the course of development of human communities towards industrially advanced societies of today, there have been changes not only in economic conditions in the majority of fields of human activity but also in the ways of providing for food, which went hand in hand with changes in living conditions. Large‐scale industrial production has brought about major changes in the way of life of the population. The development of industrial agglomerations results in a growing number of city dwellers, most of whom have no chance of producing foodstuffs of their own in kind. The distance between residential and industrial areas has been growing, the number of employed women has risen considerably. These are but a few factors affecting the way of boarding, particularly in households.

Tourism and airtransport, although mass tourism was possible by other transports facilities, the great step forward was put with developments in airtransport.

In systems theory, authors such as Klir, Miller, Yang, Lin and Ma, Backlund, etc. have developed different definitions of the system concept in function of both the type of variables used and the type of connection between variables. The concept of the subsystem, however, tends not to vary substantially from author to author, and this leads to a new system definition based on the subsystem concept, analysing the possible cases of interaction between subsystems and obtaining results for the overall system from an analysis of its subsystems.

A number of U.S. studies have documented an optimistic bias in analysts’ forecasts of earnings. This study investigates whether the optimistic bias and asymmetric behavior of forecast errors found in most U.S. studies exists in Japan. We find that for firms reporting profits, Japanese analysts’ forecasts have much greater accuracy and exhibit a small pessimistic bias in comparison to firms reporting losses, where analysts’ forecasts exhibit extremely poor accuracy and an extremely significant optimistic bias. The lack of ability to forecast losses is due to their transitory nature and not due to earnings management. Forecast accuracy and bias are not related to firm size, but are related to the magnitude of reported lossess and profits.

When in‐plant and college‐based courses are run for supervisors and managers, it is conventional to use a U‐shaped seating arrangement in the training room to promote participation and discussion. However, at each class session, people will tend to sit with the same companions habitually, which may be more comfortable, but less productive than if they sat with different people each time.

Using the ALIENOR transformation avoids the problem of determining the first and second derivatives of the objective functional f when using the multidimensional bissection method. Knowledge of the Lipschitzian constant C is generally sufficient for using this method, and therefore for determining the global maximum of f defined on a compact set.

For each natural n let Fⁿ denote the collection of mappings of Rⁿ onto itself defined by: F ∈Fⁿ if and only if there exist n strictly monotone increasing functions f_k mapping R onto itself such that for each x =[x₁, …, x_n]^T ∈ Rⁿ, F(x) = [f₁(x₁), …, f_n(x_n)]^T. The following new property of the class P₀ of matices is proved: a real n × n matrix A belongs to P₀ if and only if for every G, H ∈ Fⁿ the set S₀ = { x ∈ Rⁿ : − G(x) ≤Ax ≤ − H(x) } is bounded. As an illustration of this property a method of estimating the unique solution of the nonlinear equation F(x) + A(x) =b describing the large class of DC transistor circuits is developed. This can improve the efficiency of known computation algorithms. Numerical examples of transistor circuits illustrate in detail how the method works in practice.

Based on the definitions of poor data, an unascertained model and four axioms, condition functions and range etc. were analyzed then induced second‐order condition function, complemental condition function, connection function and the rule set of some signs concludes with the forecast method, which consists of four theorems and ten inferences, in the condition of data number m (m≥2) in Rⁿ.