We present a version of the HOL Light system that supports undoing definitions in such a way that this does not compromise the soundness of the logic. In our system the code that keeps track of the constants that have been defined thus far has been moved out of the kernel. This means that the kernel now is purely functional. The changes to the system are small. All existing HOL Light developmen...

OBJECTIVES This study sought to investigate the impact of the Thai "Health Insurance for People with Citizenship Problems" (HI-PCP) on access to care for stateless patients, compared to Universal Coverage Scheme patients and the uninsured, using inpatient utilization as a proxy for impact. METHODS Secondary data analysis of inpatient records of Kraburi Hospital, Ranong province, between 2009 ...

We investigate the computing power of stateless multicounter machines with reversal-bounded counters. Such a machine has m-counters and it operates on a one-way input delimited by left and right end markers. The move of the machine depends only on the symbol under the input head and the signs of the counters (zero or positive). At each step, every counter can be incremented by 1, decremented by...

Nodes use IPv6 stateless address autoconfiguration to generate addresses using a combination of locally available information and information advertised by routers. Addresses are formed by combining network prefixes with an interface identifier. On an interface that contains an embedded IEEE Identifier, the interface identifier is typically derived from it. On other interface types, the interfa...

Rate-Delay (RD) Network Services constitute a promising differentiated-services architecture for multi-provider networks, by offering users a choice between high throughput or low queuing delay at bottleneck links. An RD router provides service differentiation via transmission scheduling and by managing two FIFO queues. To ensure strict delay bounds, an RD router tracks arrival times of packets...

This paper proposes a new method of bandwidth allocation during congestion, called the proportional allocation of bandwidth. Traditionally, max-min fairness has been proposed to allocate bandwidth under congestion. Our allocation scheme considers the situation where flows might have different subscribed information rates, based on their origin. In proportional allocation of bandwidth, during co...

Steganography is the science of hiding the very presence of a secret message within a public com-munication channel. In Crypto 2002, Hopper, Langford, and von Ahn proposed the first complexity-theoretic definition and constructions of stegosystems. They later pointed out a flaw in their basic con-struction. Their proposed fix for this flaw dramatically reduces the efficiency of ...