1,544 research outputs found
Monadic Sequence Testing and Explicit Test-Refinements
We present an abstract framework for sequence testing that is implemented in Isabelle/HOL-TestGen. Our framework is based on the theory of state-exception monads, explicitly modelled in HOL, and can cope with typed input and output, interleaving executions including abort, and synchronisation. The framework is particularly geared towards symbolic execution and has proven effective in several large case-studies involving system models based on large (or infinite) state. On this basis, we rephrase the concept of test-refinements for inclusion, deadlock and IOCO-like tests, together with a formal theory of its rela- tion to traditional, IO-automata based notions
Biologische und biomechanische Grundlagen der arthroskopischen Rotatorenmanschettenrekonstruktion
Zusammenfassung: Eine erfolgreiche arthroskopische Rotatorenmanschettenrekonstruktion im Langzeitverlauf ist nicht nur von der rein technischen Wiederherstellung der Kontinuität des Muskel-Sehnen-Knochen-Komplexes, sondern auch von vielen weiteren Faktoren abhängig. Neben einer korrekten und schonenden Operationstechnik spielen u.a. biologische Faktoren wie die Muskel- und Sehnenqualität der Rotatorenmanschette sowie die Knochenqualität der Reinsertionszone für das Outcome eine wesentliche Rolle. In diesem Zusammenhang sind insbesondere die fettige Infiltration, Atrophie und Retraktion der rupturierten Rotatorenmanschette, die Sehnendegeneration sowie Osteopenie der Reinsertionszone an den Tuberkula zu berücksichtigen. Des Weiteren müssen grundlegende biomechanische Prinzipien bei der Nahttechnik und Fadenankerplatzierung beachtet werden, um ein technisch bedingtes Versagen der Refixation zu vermeide
Formal Network Models and Their Application to Firewall Policies (UPF-Firewall)
We present a formal model of network protocols and their application to modeling firewall policies. The formalization is based on the Unified Policy Framework (UPF). The formalization was originally developed with for generating test cases for testing the security configuration actual firewall and router (middle-boxes) using HOL-TestGen. Our work focuses on modeling application level protocols on top of tcp/ip
Recent Developments in OCL and Textual Modelling
The panel session of the 16th OCL workshop featured a lightning talk session for discussing recent developments and open questions in the area of OCL and textual modelling. During this session, the OCL community discussed, stimulated through short presentations by OCL experts, tool support, potential future extensions, and suggested initiatives to make the textual modelling community even more successful. This collaborative paper, to which each OCL expert contributed one section, summarises the discussions as well as describes the recent developments and open questions presented in the lightning talks
Scheduling Bidirectional Traffic on a Path
We study the fundamental problem of scheduling bidirectional traffic along a
path composed of multiple segments. The main feature of the problem is that
jobs traveling in the same direction can be scheduled in quick succession on a
segment, while jobs in opposing directions cannot cross a segment at the same
time. We show that this tradeoff makes the problem significantly harder than
the related flow shop problem, by proving that it is NP-hard even for identical
jobs. We complement this result with a PTAS for a single segment and
non-identical jobs. If we allow some pairs of jobs traveling in different
directions to cross a segment concurrently, the problem becomes APX-hard even
on a single segment and with identical jobs. We give polynomial algorithms for
the setting with restricted compatibilities between jobs on a single and any
constant number of segments, respectively
ATLTest: A White-Box Test Generation Approach for ATL Transformations
International audienceMDE is being applied to the development of increasingly complex systems that require larger model transformations. Given that the specification of such transformations is an error-prone task, techniques to guarantee their quality must be provided. Testing is a well-known technique for finding errors in programs. In this sense, adoption of testing techniques in the model transformation domain would be helpful to improve their quality. So far, testing of model transformations has focused on black-box testing techniques. Instead, in this paper we provide a white-box test model generation approach for ATL model transformations
Ownership and control in a competitive industry
We study a differentiated product market in which an investor initially owns a controlling stake in one of two competing firms and may acquire a non-controlling or a controlling stake in a competitor, either directly using her own assets, or indirectly via the controlled firm. While industry profits are maximized within a symmetric two product monopoly, the investor attains this only in exceptional cases. Instead, she sometimes acquires a noncontrolling stake. Or she invests asymmetrically rather than pursuing a full takeover if she acquires a controlling one. Generally, she invests indirectly if she only wants to affect the product market outcome, and directly if acquiring shares is profitable per se. --differentiated products,separation of ownership and control,private benefits of control
Isabelle/DOF. User and Implementation Manual
The software for which this is the manual is available via the DOI in this recordIsabelle/DOF provides an implementation of DOF on top of Isabelle/HOL. DOF itself is a
novel framework for defining ontologies and enforcing them during document development
and document evolution. Isabelle/DOF targets use-cases such as mathematical texts referring to a theory development or technical reports requiring a particular structure. A major
application of DOF is the integrated development of formal certification documents (e.g.,
for Common Criteria or CENELEC 50128) that require consistency across both formal and
informal arguments.
Isabelle/DOF is integrated into Isabelle’s IDE, which allows for smooth ontology development as well as immediate ontological feedback during the editing of a document. Its checking
facilities leverage the collaborative development of documents required to be consistent with
an underlying ontological structure.
In this user-manual, we give an in-depth presentation of the design concepts of DOF’s Ontology Definition Language (ODL) and describe comprehensively its major commands. Many
examples show typical best-practice applications of the system. Isabelle/DOF is the first ontology language supporting machine-checked links between the formal and informal parts in
an LCF-style interactive theorem proving environment.IRT System
Methane, ammonia, and their irradiation products at the surface of an intermediate-size KBO? A portrait of Plutino (90482) Orcus
Orcus is an intermediate-size 1000km-scale Kuiper Belt Object in 3:2
mean-motion resonance with Neptune, in an orbit very similar to that of Pluto.
We present visible and near-infrared photometry and spectroscopy obtained with
the Keck 10m-telescope and the Gemini 8m-telescope . We confirm the unambiguous
detection of crystalline water ice as well as absorption in the 2.2\mu m
region. Both in the visible and near-infrared Orcus' spectral properties appear
to be homogeneous over time (and probably rotation) at the resolution
available. From Hapke radiative transfer models involving intimate mixtures of
various ices we find for the first time that ammonium (NH+4) and traces of
ethane (C2 H6), which are most probably solar irradiation products of ammonia
and methane, and a mixture of methane and ammonia (diluted or not) are the best
candidates to improve the description of the data with respect to a simple
water ice mixture (Haumea type surface). The possible more subtle structure of
the 2.2\mu m band(s) should be investigated thoroughly in the future for Orcus
and other intermediate size Plutinos to better understand the methane and
ammonia chemistry at work, if any. We investigated the thermal history of Orcus
with a new 3D thermal evolution model. Simulations over 4.5 x109 yrs with an
input 10% porosity, bulk composition of 23% amorphous water ice and 77% dust,
and cold accretion show that even with the action of long-lived radiogenic
elements only, Orcus should have a melted core and most probably suffered a
cryovolcanic event in its history which brought large amounts of crystalline
ice to the surface. The presence of ammonia in the interior would strengthen
the melting process. The crystalline water ice possibly brought to the surface
by a past cryovolcanic event sbe detectable after several billion years despite
the irradiation eects, as demonstrated by recent laboratory experiments.Comment: 15 pages, 9 figure
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