Remote sensing of geomorphodiversity linked to biodiversity — part III: traits, processes and remote sensing characteristics

Remote sensing (RS) enables a cost-effective, extensive, continuous and standardized monitoring of traits and trait variations of geomorphology and its processes, from the local to the continental scale. To implement and better understand RS techniques and the spectral indicators derived from them in the monitoring of geomorphology, this paper presents a new perspective for the definition and recording of five characteristics of geomorphodiversity with RS, namely: geomorphic genesis diversity, geomorphic trait diversity, geomorphic structural diversity, geomorphic taxonomic diversity, and geomorphic functional diversity. In this respect, geomorphic trait diversity is the cornerstone and is essential for recording the other four characteristics using RS technologies. All five characteristics are discussed in detail in this paper and reinforced with numerous examples from various RS technologies. Methods for classifying the five characteristics of geomorphodiversity using RS, as well as the constraints of monitoring the diversity of geomorphology using RS, are discussed. RS-aided techniques that can be used for monitoring geomorphodiversity in regimes with changing land-use intensity are presented. Further, new approaches of geomorphic traits that enable the monitoring of geomorphodiversity through the valorisation of RS data from multiple missions are discussed as well as the ecosystem integrity approach. Likewise, the approach of monitoring the five characteristics of geomorphodiversity recording with RS is discussed, as are existing approaches for recording spectral geomorhic traits/ trait variation approach and indicators, along with approaches for assessing geomorphodiversity. It is shown that there is no comparable approach with which to define and record the five characteristics of geomorphodiversity using only RS data in the literature. Finally, the importance of the digitization process and the use of data science for research in the field of geomorphology in the 21st century is elucidated and discussed

An Introduction to Abstract State Machines

This report explains basic notions and concepts of Abstract State Machines (ASM) as well as notation for defining ASM models. The objective here is to provide an intuitive understanding of the formalism; for a rigorous definition of the mathematical foundations of ASM, the reader is referred to [2] and [3]. Further references on ASM-related material can be found on the ASM Web Pages [1]

T.: Formal Description of a Distributed Location Service for Ad Hoc Mobile Networks

Abstract. We define here a distributed abstract state machine (DASM) [7] of the network or routing layer of mobile ad hoc networks [13]. Such networks require routing strategies substantially different from those used in static communication networks, since storing and updating large routing tables at mobile hosts would congest the network with administration packets very fast. In [1], the hypercubic location service is presented, which considers a very strong definition of fault-tolerance thereby improving state-of-the-art ad hoc routing protocols in several respects. Our goal in modeling the protocols for the distributed location service and the position based routing is twofold. First, we support the definition and validation of wireless communication protocols and implementations based thereon. Second, we feel that the abstract computation model naturally reflects the layering principle of communication architectures in combination with an uncompromisingly local view of the application domain. Thus we can identify fundamental semantic concepts, such as concurrency, reactivity and asynchronism, directly with the related concepts as imposed by the given application context.

Systems Level Specification and Modelling of Reactive Systems: Concepts, Methods, and Tools

As part of a comprehensive design concept for complex reactive systems we investigate the derivation of formal requirements and design specifications at systems level. We discuss the meaning of correctness with respect to the embedding of mathematical models into the physical world. A crucial aspect in our attempt to make the logic link between the application domain specific view and the formal view explicit is the concept of evolving algebra [13, 14]; it provides the formal basis of a specification methodology which has successfully been applied to a variety of specification and verification problems. We introduce an evolving algebra abstract machine as a conceptual framework for the development of tools for machine based analysis and execution of evolving algebra specifications

A Formal Specification of the PVM Architecture

Introduction PVM (Parallel Virtual Machine) is a software system 2 that serves as a general purpose environment for heterogeneous distributed computing [1,2]. We develop here a mathematical definition of PVM at a level of abstraction and precision which is tailored to the needs of a programmer who wants to be brought, fast and reliably, to a correct understanding of the system at the C--interface. We build our model in such a way that it can also be used as basis for a series of stepwise refinements, leading in a provably correct way to actual PVM code. Our specification is easily adaptable to extensions and modifications of single features, parts or interfaces of the system; such ease with extensions seems to us to be a particularly important goal for specifying a complex still changing system. Our specification methodology is based on Gurevich's concept of evolving algebra. This method allows to avoid formal overhead, enabli