external environment

We present a new tool, named DART, for automatically testing software that combines three main techniques: (1) automated extraction of the interface of a program with its external environment using static source-code parsing; (2) automatic generation of a test driver for this interface

Abstract not found

A robot exploring an unknown environmentmay need to build a world model from sensor measurements. In order to integrate all the frames of sensor data, it is essential to align the data properly. An incremental approach has been typically used in the past, in which each local frame of data is aligned to a cumulative global model, and then merged to the model. Because different parts of the model are updated independently while there are errors in the registration, such an approachmay result in an inconsistent model. In this paper, we study the problem of consistent registration of multiple frames of measurements (range scans), together with the related issues of representation and manipulation of spatial uncertainties. Our approachistomaintain all the local frames of data as well as the relative spatial relationships between local frames. These spatial relationships are modeled as random variables and are derived from matching pairwise scans or from odometry. Then we formulat...

: Reasoning about knowledge seems to play a fundamental role in distributed systems. Indeed, such reasoning is a central part of the informal intuitive arguments used in the design of distributed protocols. Communication in a distributed system can be viewed as the act of transforming the system's state of knowledge. This paper presents a general framework for formalizing and reasoning about knowledge in distributed systems. We argue that states of knowledge of groups of processors are useful concepts for the design and analysis of distributed protocols. In particular, distributed knowledge corresponds to knowledge that is "distributed" among the members of the group, while common knowledge corresponds to a fact being "publicly known". The relationship between common knowledge and a variety of desirable actions in a distributed system is illustrated. Furthermore, it is shown that, formally speaking, in practical systems common knowledge cannot be attained. A number of weaker variants...

Chromium is a trace element of estab-lished nutritional importance for the rat (1), squirrel monkey (2), and man (3). Human deficiency of this essential micronutrient may not be uncommon (4) and has been related to abnormalities of carbohydrate metabolism in man (5-7). At this time, however, the diagnosis of chromium deficiency remains difficult; solitary plasma chromium levels do not indicate the presence of a low chromium state (3), and factors effecting the rise in plasma chromium after a glucose load (8, 9) require further investigation (3, 9). Investi-gations of nutritional deficiencies of this ele-ment have, therefore, depended primarily on

. The purpose of this paper is to propose the framework as an evaluation technique for visual programming environments. We apply it to two commercially-available dataflow languages (with further examples from other systems) and conclude that it is effective and insightful; other HCI-based evaluation

dedicated to protein structure homology modelling. It assists and guides the user in building protein homology models at different levels of complexity. A personal working environment is provided for each user where several modelling projects can be carried out in parallel. Protein sequence and structure

This paper provides an overview of the STATEMATE system, constructed over the past several years by the authors and their colleagues at Ad Cad Ltd., the R&D subsidiary of i-Logix, Inc. STATEMATE is a set of tools, with a heavy graphical orientation, in- tended for the specification, analysis, design, and documentation of large and complex reactive systems, such as real-time embedded sys- tems, control and communication systems, and interactive software or hardware. It enables a user to prepare, analyze, and debug diagram- matic, yet precise, descriptions of the system under development from three interrelated points of view, capturing structure, functionality, and behavior. These views are represented by three graphical languages, the most intricate of which is the language of statecharts [4], used to depict reactive behavior over time. In addition to the use of statecharts, the main novelty of STATEMATE is in the fact that it "understands " the entire descriptions perfectly, to the point of being able to analyze them for crucial dynamic properties, to carry out rigorous ex- ecutions and simulations of the described system, and to create run- ning code automatically. These features are invaluable when it comes to the quality and reliability of the final outcome.

This paper examines whether nancial development facilitates economic growth by scrutinizing one rationale for such a relationship; that nancial development reduces the costs of external nance to rms. Speci cally, we ask whether industrial sectors that are relatively more in need of external nance