A E Solutions (United Kingdom)

Data integration of enterprise systems typically involves combining heterogeneous data residing in different sources into a unified, homogeneous whole.This heterogeneity takes many forms and there are all sorts of significant practical and theoretical challenges to managing this, particularly at the semantic level.In this paper, we consider a type of semantic heterogeneity that is common in Model Driven Architecture (MDA) Computation Independent Models (CIM); one that arises due to the data's dependence upon the system it resides in.There seems to be no relevant work on this topic in Conceptual Modelling, so we draw upon research done in philosophy and linguistics on formalizing pure indexicals -'I', 'here' and 'now' -also known as de se (Latin 'of oneself') or the deitic centre.This reveals firstly that the core dependency is essential when the system is agentive and the rest of the dependency can be designed away.In the context of MDA, this suggests a natural architectural layering; where a new concern 'system dependence' is introduced and used to divide the CIM model into two parts; a system independent ontology model and a system dependent agentology model.We also show how this dependence complicates the integration process -but, interestingly, not reuse in the same context.We explain how this complication usually provides good pragmatic reasons for maximizing the ontology content in an 'Ontology First', or 'Ontology then Agentology' approach.

Formalization is becoming more common in all stages of the development of information systems, as a better understanding of its benefits emerges. Classification systems are ubiquitous, no more so than in domain modeling. The classification pattern that underlies these systems provides a good case study of the move toward formalization in part because it illustrates some of the barriers to formalization, including the formal complexity of the pattern and the ontological issues surrounding the “one and the many.” Powersets are a way of characterizing the (complex) formal structure of the classification pattern, and their formalization has been extensively studied in mathematics since Cantor’s work in the late nineteenth century. One can use this formalization to develop a useful benchmark. There are various communities within information systems engineering (ISE) that are gradually working toward a formalization of the classification pattern. However, for most of these communities, this work is incomplete, in that they have not yet arrived at a solution with the expressiveness of the powerset benchmark. This contrasts with the early smooth adoption of powerset by other information systems communities to, for example, formalize relations. One way of understanding the varying rates of adoption is recognizing that the different communities have different historical baggage. Many conceptual modeling communities emerged from work done on database design, and this creates hurdles to the adoption of the high level of expressiveness of powersets. Another relevant factor is that these communities also often feel, particularly in the case of domain modeling, a responsibility to explain the semantics of whatever formal structures they adopt. This paper aims to make sense of the formalization of the classification pattern in ISE and surveys its history through the literature, starting from the relevant theoretical works of the mathematical literature and gradually shifting focus to the ISE literature. The literature survey follows the evolution of ISE’s understanding of how to formalize the classification pattern. The various proposals are assessed using the classical example of classification; the Linnaean taxonomy formalized using powersets as a benchmark for formal expressiveness. The broad conclusion of the survey is that (1) the ISE community is currently in the early stages of the process of understanding how to formalize the classification pattern, particularly in the requirements for expressiveness exemplified by powersets, and (2) that there is an opportunity to intervene and speed up the process of adoption by clarifying this expressiveness. Given the central place that the classification pattern has in domain modeling, this intervention has the potential to lead to significant improvements.

This study aims to identify quantitatively the level of increased stress in civilian crime scene investigators (CSIs) whilst they were performing a variety of tasks as part of their normal duties. Mean above-average resting heart rate was used as the quantitative measure of physiological changes, recorded once a second for 12 CSIs during a working shift of 8 hours over a period of 7 days. Each CSI maintained an activity log of their work which enabled the physiological readings to be aligned to tasks undertaken. As well as physical stress, results show that CSIs undergo psychosocial stress during the examination of routine crime scenes such as domestic burglary and vehicle examination. Increased levels of stress diminished between scene visits. Reasons for increased stress reactivity at routine crime scenes are considered and opportunities for further work discussed. This study demonstrates quantitatively the stress undergone by civilian CSIs and questions the effect this might have on the effective recovery of forensic material from the crime scene as well as the welfare of the CSI.

This paper describes the attitude ground system (AGS) design to be used for support of the Magnetospheric MultiScale (MMS) mission. The AGS exists as one component of the mission operations control center. It has responsibility for validating the onboard attitude and accelerometer bias estimates, calibrating the attitude sensors and the spacecraft inertia tensor, and generating a definitive attitude history for use by the science teams. NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Maryland is responsible for developing the MMS spacecraft, for the overall management of the MMS mission, and for mission operations. MMS is scheduled for launch in 2014 for a planned two-year mission. The MMS mission consists of four identical spacecraft flying in a tetrahedral formation in an eccentric Earth orbit. The relatively tight formation, ranging from 10 to 400 km, will provide coordinated observations giving insight into small-scale magnetic field reconnection processes. By varying the size of the tetrahedron and the orbital semi-major axis and eccentricity, and making use of the changing solar phase, this geometry allows for the study of both bow shock and magnetotail plasma physics, including acceleration, reconnection, and turbulence. The mission divides into two phases for science; these phases will have orbit dimensions of 1.2 x 12 Earth radii in the first phase and 1.2x25 Earth radii in the second in order to study the dayside magnetopause and the nightside magnetotail, respectively. The orbital periods are roughly one day and three days for the two mission phases. Each of the four MMS spacecraft will be spin stabilized at 3 revolutions per minute (rpm), with the spin axis oriented near the ecliptic north pole but tipped approximately 2.5 deg towards the Sun line. The main body of each spacecraft will be an eight-sided platform with diameter of 3.4 m and height of 1.2 m. Several booms are attached to this central core: two axial booms of 14.9 m length, two radial magnetometer booms of 5 m length, and four radial wire booms of 60 m length. Attitude and orbit control will use a set of axial and radial thrusters. A four-head star tracker and a slit-type digital Sun sensor (DSS) provide input for attitude determination. In addition, an accelerometer will be used for closed-loop orbit maneuver control. The primary AGS product will be a daily definitive attitude history. Due to power limitations, the star tracker and accelerometer data will not be available at all times. However, tracker data from at least 10 percent of each orbit and continuous DSS data will be provided. An extended Kalman filter (EKF) will be used to estimate the three-axis attitude (i.e., spin axis orientation and spin phase) and rotation rate for all times when the tracker data is valid. For other times, the attitude is generated by assuming a constant angular momentum vector in the inertial frame. The DSS sun pulse will provide a timing signal to maintain an accurate spin phase. There will be times when the Sun is occulted and DSS data is not available. If this occurs at the start or end of a definitive attitude product, then the spin phase will be extrapolated using the mean rate determined by the EKF.

In common with many other government defence departments, the UK Ministry of Defence (MoD) has realised that it has a plethora of legacy systems that were procured as domain specific with little emphasis given to integration requirements. In particular, it realised that the lack of integration between a significant number of the legacy air defence command and control (AD-C2) systems meant it could not deliver the increased agility needed for joint force AD and that current approaches to integration were unlikely to resolve the problem. They realised that they needed a new approach that demonstrably worked. This paper describes a programme initiated by the MoD to address this problem through the formulation of a novel solution and its demonstration in the tactical AD-C2 environment using a sample of these existing legacy systems. It describes the ontological solution deployed to resolve the ‘hard’ semantic interoperability challenge. It outlines the physical and semantic architecture that was developed to ...

By controlled experiments that simulate marine conditions, it is shown that accelerated weathering and mineral authigenesis occur during the combined process of digestion, ingestion and excretion of sediment by worms. Previously characterized synthetic mud, composed of finely ground, low-grade metamorphic slate dominated by highly crystalline chlorite and muscovite, was unchanged in control tanks over a 20 week time scale, but was significantly different in faecal samples from an experimental tank populated with the annelid Arenicola marina . Chlorite was preferentially destroyed during digestion and both chlorite and muscovite underwent peak broadening with a skew developing towards higher lattice spacings. Neoformed minerals with very high d -spacings and a mineral with 0.75 nm basal lattice spacing (possibly berthierine) were detected in the cast samples. It is postulated that the lowered pH microenvironment in the guts of organisms may accelerate mineral dissolution and precipitation processes during ingestion. These results show that macrobiotic activity significantly accelerates weathering and mineral degradation along with mineral authigenesis. Neoformed minerals produced in this way would be likely to form the precursors of diagenetic clay mineral cements and thus have an impact on sandstone reservoir quality.