健美操对形体的影响

随着现代化进程的加速,生活、工作的繁忙。被誉为现代文明病之一的肥胖病越来越普遍。为了克服肥胖,应运而生的各种减肥手段、方法、措施层出不穷,但结局大多是消极。实验证明,要想控制体重、减少脂肪、保持形体,最好的方法就是积极科学的体育锻炼。本文通过有氧健美操,对减轻体重、保持形体、增强体质的作用进行实验来加以探讨。     

Strategyproof mechanisms for 2-facility location games with minimax envy

Journal of Combinatorial Optimization - We study a fairness-based model for 2-facility location games on the real line where the social objective is to minimize the maximum envy over all agents....     

The weighted link ring loading problem

In the weighted link ring loading problem, we are given an n-node undirected ring network. Each of its links is associated with a weight. Traffic demands are given for each pair of nodes in the ring. The load of a link is the sum of the flows routed through the link, and the weighted load of a link is the product of its weight and the smallest integer not less than its load. The objective of the problem is to find a routing scheme such that the maximum weighted load on the ring is minimized. In this paper we consider three variants: (i) demands may be split into two parts, and then each part is sent in a different direction; (ii) demands are allowed to be split into two parts but restricted to be integrally split; (iii) each demand must be entirely routed in either of the two directions, clockwise or counterclockwise. We first prove that the first variant is polynomially solvable. We then present a pseudo-polynomial time algorithm for the second one. Finally, for the third one, whose NP-hardness can be drawn from the result in the literature, we derive a polynomial-time approximation scheme (PTAS).