An example of a regular space that is not completely regular

A simpler example of regular space that is not completely regular is attempted.     

On estimating the regular normal cone to constraint systems and stationarity conditions

Estimating the regular normal cone to constraint systems plays an important role for the derivation of sharp necessary optimality conditions. We present two novel approaches and introduce a new stationarity concept which is stronger than M-stationarity. We apply our theory to three classes of mathematical programs frequently arising in the literature.     

A pseudo active kinematic constraint for a biological living soft tissue: An effect of the collagen network

Recent studies in mammalian hearts show that left ventricular wall thickening is an important mechanism for systolic ejection, and that during contraction the cardiac muscle develops significant stresses in the muscular cross-fiber direction. We suggested that the collagen network surrounding the muscular fibers could account for these mechanical behaviors. To test this hypothesis we develop a model for large deformation response of active, incompressible, nonlinear elastic and transversely isotropic living soft tissue (such as cardiac or arteries tissues) in which we include a coupling effect between the connective tissue and the muscular fibers. Then, a three-dimensional finite element formulation including this internal pseudo-active kinematic constraint is derived. Analytical and finite element solutions are in a very good agreement. The numerical results show this wall thickening effect with an order of magnitude compatible with the experimental observations.     

The line digraph of a regular and pancircular digraph is also regular and pancircular

This paper introduces thepancircularity property on digraphs: a digraphD is said to bepancircular if it contains circuits of every lengthL for all 1 L # E(D). We discuss preservation of pancircularity under the line-digraph operation, and prove the theorem stated in the title. As a corollary, all DeBruijn graphs are proved to be pancyclic and pancircular.     

Conditions under which the least compactification of a regular continuous frame is perfect

We characterize those regular continuous frames for which the least compactification is a perfect compactification. Perfect compactifications are those compactifications of frames for which the right adjoint of the compactification map preserves disjoint binary joins. Essential to our characterization is the construction of the frame analog of the two-point compactification of a locally compact Hausdorff space, and the concept of remainder in a frame compactification. Indeed, one of the characterizations is that the remainder of the regular continuous frame in each of its compactifications is compact and connected.     

Parallel machine scheduling problems considering regular measures of performance and machine cost

This research considers a broad range of scheduling problems in the parallel machines environment. Schedules are evaluated according to two independent components of the objective function: (1) machine cost consisting of a fixed cost and a variable cost; and (2) a regular measure of performance. This study is only one of a few that take the selection of machines among those available as a decision variable. For machine cost with concave functions, we derive the general characteristics of optimal solutions with respect to decisions on the number of machines to use and the way to load the machines. Our analysis is not restricted to the machine cost criterion, but may be extended to other measures with concave functions. Furthermore, we provide a Pareto efficient perspective in understanding the tradeoff between machine cost and any regular measure of performance.     

Every connected regular graph of even degree is a Schreier coset graph

Using Petersen's theorem, that every regular graph of even degree is 2-factorable, it is proved that every connected regular graph of even degree is isomorphic to a Schreier coset graph. The method used is a special application of the permutation voltage graph construction developed by the author and Tucker. This work is related to graph imbedding theory, because a Schreier coset graph is a covering space of a bouquet of circles.     

Computing the nucleolus when the characteristic function is given implicitly: A constraint generation approach

We study a class of cooperative games that is such that the values of the characteristic function are given implicitly. A constraint generation procedure can be applied to compute the nucleolus (and related solutions) of such a game, even if the number of players is large.     

The lattice of regular subsemigroups of a regular semigroup

It is shown that all regular subsemigroups of an arbitrary regular semigroup form a lattice. The properties of this lattice are investigated.     

Stochastic joint replenishment problem under a fill rate constraint with controllable lead times and shared cost allocation

In a family of items under coordinated inventory replenishments, some products may be replenished at the same time, which in turn implies that some lead time components and costs may be shared among them. This paper investigates this aspect in the context of the joint replenishment problem under the class of cyclic policies, assuming random demands and controllable lead times, and imposing a fill rate constraint for each item.     

Estimating searching cost of regular path queries on large graphs by exploiting unit-subqueries

Journal of Heuristics - Regular path queries (RPQs) are widely used on a graph whose answer is a set of tuples of nodes connected by paths corresponding to a given regular expression. Traditional...     

The use of higher order finite difference schemes is not dangerous

We discuss the issue of choosing a finite difference scheme for numerical differentiation in case the smoothness of the underlying function is unknown. If low order finite difference schemes are used for smooth functions, then the best possible accuracy cannot be obtained. This can be circumvented by using higher order finite difference schemes, but there is concern that this may cause bad error behavior. Here we show, theoretically and by numerical simulation, that this is not the case. However, by doing so, the step-size should be chosen a posteriori.     

四正则图的分离问题是NP-完备的

本 文证明了 四正则图 的最小平 分问题是 Ｎ Ｐ完备的 ,因而可得 到四正 则图的最 小 α分离问 题也是 Ｎ Ｐ完备 的