OBJECTIVE To date, there is no consensus to evaluate the most appropriate category of the nodal metastasis for precise predication the prognosis of gastric cancer patients with positive node metastasis after curative surgery. METHODS We retrospectively analyzed the clinicopathologic characteristics and overall survival (OS) of 299 gastric cancer patients with positive node metastasis after cu...

The optimization of channel assignment in cellular mobile networks is an NP-complete combinatorial optimization problem. For any reasonable size network, only sub-optimal solutions can be obtained by heuristic algorithms. In this paper, six channel assignment heuristic algorithms are proposed and evaluated. They are the combinations of three channel assignment strategies and two cell ordering m...

The influence of explant nodal positions on the in vitro shoot growth and proliferation were studied in the two rose cvs. ‘Bianca’ and ‘El Torro’. Third, fourth and fifth nodal explants were cultured on the modified MS medium supplemented with 1.0 and 5.0 mg/l BA. In both the cultivars, higher rate of proliferation (‘Bianca’ 3.75; ‘El Torro’ 2.65) were obtained from the explants distal to the a...

We focus on a three-stage supply chain problem for fast moving consumer goods including a supplier, a manufacturer and customers. There are different orders over identical cycles, to be processed in production site. The problem is to find a joint cyclic schedule of raw material procurement and job scheduling minimized the total cost comprised of raw material ordering cost and holding cost, prod...

In Code Division Multiple Access (CDMA) communications, Multiuser Detection (MUD), that reduces the multi-access interference (MAI) and that solves the near-far problem, has been widely studied for over 15 years. Since optimal multiuser detection is generally NP hard, many sub-optimal algorithms that provide reliable performance and ensure polynomial complexity have been proposed. However, ther...

In this paper we prove some stochastic comparisons results for progressive type II censored order statistics. The problem of stochastically comparing concomitants of the two progressive type II censored order statistics with possibly different schemes, under different kinds of dependence between X and Y is considered and it is proved that if Y is stochastically increasing (decreasing) in X, ...

We consider a supplier who faces stationary demand and uses dynamically updated forecast information to place orders to an upstream distributor. The order size is restricted and each order entails a high fixed cost. We characterize the form of the optimal policy in the special case where the fixed cost of ordering is high enough to warrant all-or-nothing ordering in each period.

The problem of finding an optimal variable ordering for Binary Decision Diagrams (BDD) or Multi-Valued Decision Diagrams (MDD) is widely known to be NP-Complete. This paper presents a survey of static heuristic techniques applied to ordering the variables of the BDD/MDD under construction in order to minimize the overall size of the resulting decision diagram.

We present new necessary optimality conditions for εe–Pareto optimal solutions of constrained vector optimization problems with empty interior ordering cones. We use the dual-space approach based on advanced tools of variational analysis and generalized differentiation. It allows us not implement any scalarization technique while be able to establish necessary results for nonconvex and nonsolid...

The local RBF is becoming increasingly popular as an alternative to the global version that suffers from ill-conditioning. In this paper, we study analytically the convergence behavior of the local RBF method as a function of the number of nodes employed in the scheme, the nodal distance, and the shape parameter. We derive exact formulas for the first and second derivatives in one dimension, an...