Cuckoo: a Language for Implementing Memory- and Thread-safe System Services

This paper is centered around the design of a thread- and memory-safe language, primarily for the compilation of application-specific services for extensible operating systems. We describe various issues that have influenced the design of our language, called Cuckoo, that guarantees safety of programs with potentially asynchronous flows of control. Comparisons are drawn between Cuckoo and related software safety techniques, including Cyclone and software-based fault isolation (SFI), and performance results suggest our prototype compiler is capable of generating safe code that executes with low runtime overheads, even without potential code optimizations. Compared to Cyclone, Cuckoo is able to safely guard accesses to memory when programs are multithreaded. Similarly, Cuckoo is capable of enforcing memory safety in situations that are potentially troublesome for techniques such as SFI

On a Service-Oriented Approach for an Engineering Knowledge Desktop

Increasingly, manufacturing companies are shifting their focus from selling products to providing services. As a result, when designing new products, engineers must increasingly consider the life cycle costs in addition to any design requirements. To identify possible areas of concern, designers are required to consult existing maintenance information from identical products. However, in a large engineering company, the amount of information available is significant and in wide range of formats. This paper presents a prototype knowledge desktop suitable for the design engineer. The Engineering Knowledge Desktop analyses and suggests relevant information from ontologically marked-up heterogeneous web resources. It is designed using a Service-Oriented Architecture, with an ontology to mediate between Web Services. It has been delivered to the user community for evaluation

Optimal capital investment under uncertainty: An extension

This paper develops a model for optimal capital investment in continuous time when both existing and new capital stocks are subject to uncertainty. The model is generalized to allow for large and infrequent changes in the dynamics of the capital stock, which may arise as a result of natural and man-made disasters.

Analyzing Economy Wide Effects of Trade Liberalisation on Vietnam using a Dynamic Computable General Equilibrium Model

Since its reform process in the late 1980s, Vietnam has emerged as a rapidly growing economy with growth rates surpassing its more developed ASEAN neighbours. This paper aims to consider the economy wide impacts of trade liberalisation on Vietnam. We approach this by way of multi-region, multi-good, dynamic growth computable general equilibrium (DCGE) model. We find that trade liberalisation has caused a large fall in wage inequality thus increasing the welfare of unskilled workers in Vietnam. There is also evidence of a shift away from agriculture towards low-tech and intermediate manufacturing sectors. Additionally, there are significant gains in terms of large physical and human capital accumulation.

The Changing Relation Between the Canadian and U.S. Yield Curves

The term structures of Canada and of the United States, two countries with historically close economic ties, have been closely linked. We investigate the link between Canadian and U.S. yield curves and show previously strong correlations between yield curve components dissipate after Canadian monetary policy reforms in the early 1990s. First, the effect is particularly evident in the diminished cross-country correlations of the short term bond yields. Secondly, cross-country yields are cointegrated before the reforms, but not afterwards. Lastly, the results on the term structure are shown using a vector autoregression with an endogenously determined break date for Canadian and U.S. estimates of the three-factor Nelson-Siegel (1987) yield curve model.

Worst-Case Analysis of Network Design Problem Heuristics

The Optimal Network problem (as defined by Scott [16]) consists of selecting a subset of arcs that minimizes the sum of the shortest paths between all nodes subject to a budget constraint. This paper considers the worst-case behavior of heuristics for this prob'em. Let n be the number of nodes in the network and e be a constant between 0 and 1. For a general class of Optimal Network Problems, we show that the question of finding a solution which is always less than n times the optimal solution is NP-complete. This indicates that all polynomial-time heuristics for the problem most probably have poor worst-case performance. An upper bound for worst-case heuristic performance of 2n times the optimal solution is also derived. For a restricted version of the Optimal Network problem we describe a procedure whose maximum percentage of error is bounded by a constant.This research was supported, in part, by the U. S. Department of Transportation under Contract DOT-TSC-1058, Transportation Advanced Research Program (TARP)

A Survey of Network Design Problems

Network design problems arise in many different application areas such as air freight, highway traffic, and communication systems. The intention of this survey is to present a coherent unified view of a number of papers in the network design literature. We discuss suggested solution procedures, computational experience, relations between various network models, and potential application areas. Promising topics of research for improving, solving, and extending the models reviewed in this survey are also indicated.Supported in part by the U.S. Department of Transportation under contract DOT-TSC-1058, Transportation Advanced Research Program (TARP)

Syntheses, Structures, and Photoluminescence of 1-D Lanthanide Coordination Polymers

Five new lanthanide 1-D coordination polymers are reported which are formed from flexible salen type Schiff-base ligands H(2)L and H(2)L' (H(2)L = N, N(1)-ethylene bis(salicylideneimine); H(2)L' = N,N(1)-bis(3-methoxysalicylidene) ethylene-1,2-diamine). The polymeric structures are formed by bridging neutral H(2)L units in the case of {[Ln(2)L(2)(CF(3)SO(3))(H(2)L)(4)(MeOH)]center dot CF(3)SO(3)}(n) (Ln = Eu (1), Nd (2) and Er (3)), and by acetate (OAc(-)) groups in [Yb(2)(L)(2)(OAc)(2)(MeOH)(2)](n) (4) and {[Tb(3)(L')(2)(OAc)(5)]center dot Et(2)O center dot(MeOH)(0.5)}(n) (5). The structures of 1-5 were determined by single crystal X-ray crystallographic studies and the luminescence properties of 1 and 5 in MeOH solution were determined.ong Kong Baptist University FRG/06-07/II-16Hong Kong Research Grants Council HKBU 202407Robert A. Welch Foundation F-816Texas Higher Education Coordinating Board ARP 003658-0010-2006Petroleum Research FundAmerican Chemical Society 47014-AC5Chemistr