Re-imagining French lexicography: The dictionnaire vivant de la langue française

The Dictionnaire vivant de la langue française (DVLF), developed by The ARTFL Project at the University of Chicago, represents an experimental, interactive, and community-based approach to French lexicography. The DVLF enables broad public access to a wide variety of linguistic tools and resources, with the goal of changing user interaction with dictionaries and providing better descriptions of emergent word use. In this article we describe the history of the DVLF and provide a survey of similar community-oriented electronic dictionaries. We then proceed to a presentation of the dictionary’s many features, including the variety of its definitions and mechanisms for user interaction. The article concludes with a discussion of ARTFL’s plans for the future developement of the DVLF

Reusable Software Components for Robots Using Fuzzy Abstractions

Mobile robots today, while varying greatly in design, often have a large number of similarities in terms of their tasks and goals. Navigation, obstacle avoidance, and vision are all examples. In turn, robots of similar design, but with varying configurations, should be able to share the bulk of their controlling software. Any changes required should be minimal and ideally only to specify new hardware configurations. However, it is difficult to achieve such flexibility, mainly due to the enormous variety of robot hardware available and the huge number of possible configurations. Monolithic controllers that can handle such variety are impossible to build. This paper will investigate these portability problems, as well as techniques to manage common abstractions for user-designed components. The challenge is in creating new methods for robot software to support a diverse variety of robots, while also being easily upgraded and extended. These methods can then provide new ways to support the operational and functional reuse of the same high-level components across a variety of robots

Platform Relative Sensor Abstractions across Mobile Robots using Computer Vision and Sensor Integration

Uniform sensor management and abstraction across different robot platforms is a difficult task due to the sheer diversity of sensing devices. However, because these sensors can be grouped into categories that in essence provide the same information, we can capture their similarities and create abstractions. An example would be distance data measured by an assortment of range sensors, or alternatively extracted from a camera using image processing. This paper describes how using software components it is possible to uniformly construct high-level abstractions of sensor information across various robots in a way to support the portability of common code that uses these abstractions (e.g. obstacle avoidance, wall following). We demonstrate our abstractions on a number of robots using different configurations of range sensors and cameras

Software Reuse across Robotic Platforms: Limiting the effects of diversity

Robots have diverse capabilities and complex interactions with their environment. Software development for robotic platforms is time consuming due to the complex nature of the tasks to be performed. Such an environment demands sound software engineering practices to produce high quality software. However software engineering in the robotics domain fails to facilitate any significant level of software reuse or portability. This paper identifies the major issues limiting software reuse in the robotics domain. Lack of standardisation, diversity of robotic platforms, and the subtle effects of environmental interaction all contribute to this problem. It is then shown that software components, fuzzy logic, and related techniques can be used together to address this problem. While complete software reuse is not possible, it is demonstrated that significant levels of software reuse can be obtained. Without an acceptable level of reuse or portability, software engineering in the robotics domain will not be able to meet the demands of a rapidly developing field. The work presented in this paper demonstrates a method for supporting software reuse across robotic platforms and hence facilitating improved software engineering practices

Flight evaluation of a pneumatic system for unsteady pressure measurements using conventional sensors

A flight experiment was conducted to evaluate a pressure measurement system which uses pneumatic tubing and remotely located electronically scanned pressure transducer modules for in-flight unsteady aerodynamic studies. A parametric study of tubing length and diameter on the attenuation and lag of the measured signals was conducted. The hardware was found to operate satisfactorily at rates of up to 500 samples/sec per port in flight. The signal attenuation and lag due to tubing were shown to increase with tubing length, decrease with tubing diameter, and increase with altitude over the ranges tested. Measurable signal levels were obtained for even the longest tubing length tested, 4 ft, at frequencies up to 100 Hz. This instrumentation system approach provides a practical means of conducting detailed unsteady pressure surveys in flight

Nominal Contracting and Price Flexibility in Product Markets

The search for microeconomic foundations of non-Walrasian outcomes in labor and product markets has spawned many studies of contracting. This paper emphasizes the role of contracts for market equilibrium -- for many raw materials and basic industrial commodities -- in which long-term contractual arrangements and spot markets coexist. Our principal goals are two -- (i) to explain the existence of contracts and the equilibrium fraction of trades carried out under contract, and (ii) to consider the impact of demand and supply shocks on spot prices when market trades also take place through long-term contracts. We find that the relative importance of contracting depends on, inter alia, the variance of the spot price and the sources of underlying fluctuations. Consistent with the findings of previous macroeconomic studies, we find that contracting and price rigidity are more likely the more important demand shocks are relative to supply shocks. We adapt our static model of contract price and quantity determination to discuss the adjustment of contract prices. Finally, we discuss three important applications of our multiple-price modeling structure -- to (i) analyses of the effects of changes in vertical market structure on market equilibrium in commodity markets (with specific reference to petroleum and copper), (ii) models of the optimal degree of contract indexation,and (iii) aggregate studies of "sticky prices" in macroeconomics.