The paper considers different problem formulations of topology optimization of discrete or discretized structures with eigenvalues as constraints or as objective functions. We study multiple load case formulations of minimum weight, minimum compliance problems and of the problem of maximizing the minimal eigenvalue of the structure including the effect of non-structural mass. The paper discusse...

Results from Global Positioning System (GPS) spoofing tests against Phasor Measurement Units (PMUs) are presented, demonstrating that PMUs are vulnerable to spoofing attacks. A GPS spoofer can manipulate PMU time stamps by injecting a counterfeit ensemble of GPS signals into the antenna of the PMU’s time reference receiver. A spoofer-induced timing error of only a few tens of microseconds cause...

Cross docking is one of the options to reduce lead times and inventories and to improve customer response time in supply chains. Cross-docking centres are dynamic environments where products arrive, are regrouped, and leave the same day. In this paper we focus on the process of short-term storage of unit-loads in a cross-docking environment. The goal is to determine temporary storage locations ...

This paper considers the question of identifying the parameters governing the behavior of fundamental global network problems. Many papers on distributed network algorithms consider the task of optimizing the running time successful when an O(n) bound is achieved on an n-vertex network. We propose that a more sensitive parameter is the network’s diameter Diam. This is demonstrated in the paper ...

METAFONT is Donald E. Knuth's system for alphabet design. The system allows an entire family of fonts or "meta-fonts" to be specified precisely and mathematically so that it can be produced in different sizes and styles for different raster devices. We present a new technique for defining Chinese characters hierarchically with METAFONT. We define METAFONT subroutines for commonly used portions ...

In the future, global networks will consist of a hierarchy of subnetworks called domains. For reasons of both scalability and security, domains will not reveal details of their internal structure to outside nodes. Instead, these domains will advertise only a summary, or aggregated view, of their internal structure, e.g., as proposed by the ATM PNNI standard. This work compares, by simulation, t...

This paper addresses the problem of nding the number, K, of phases present at equilibrium and their composition, in a chemical mixture of ns substances. This corresponds to the global minimum of the Gibbs free energy of the system, subject to constraints representing m b independent conserved quantities, where m b = ns when no reaction is possible and m b ne + 1 when reaction is possible and ne...

The competition between local and global driving forces is significant in a wide variety of naturally occurring branched networks. We have investigated the impact of a global minimization criterion versus a local one on the structure of spanning trees. To do so, we consider two spanning tree structures-the generalized minimal spanning tree (GMST) defined by Dror et al. [1] and an analogous stru...