Specifying ODP computational objects in Z

The computational viewpoint contained within the Reference Model of Open Distributed Processing (RM-ODP) shows how collections of objects can be configured within a distributed system to enable interworking. It prescribes certain capabilities that such objects are expected to possess and structuring rules that apply to how these objects can be configured with one another. This paper highlights how the specification language Z can be used to formalise these capabilities and the associated structuring rules, thereby enabling specifications of ODP systems from the computational viewpoint to be achieved

A Branching Time Model of CSP

I present a branching time model of CSP that is finer than all other models of CSP proposed thus far. It is obtained by taking a semantic equivalence from the linear time - branching time spectrum, namely divergence-preserving coupled similarity, and showing that it is a congruence for the operators of CSP. This equivalence belongs to the bisimulation family of semantic equivalences, in the sense that on transition systems without internal actions it coincides with strong bisimilarity. Nevertheless, enough of the equational laws of CSP remain to obtain a complete axiomatisation for closed, recursion-free terms.Comment: Dedicated to Bill Roscoe, on the occasion of his 60th birthda

Geological evidence of a palynologically defined cooling in southeastern Canada at 10 000-8000 14C yr BP

Post-glacial pollen spectra over a wide area of southeastern Canada have been interpreted as showing that the general warmth-adapted trend of regional vegetation change was interrupted between 10 000 and 8000 14C yr BP, reverting to conditions associated with a markedly cooler climate. This biotic reversal has been attributed to a climatic cooling caused by discharge of frigid water from glacial Lake Agassiz, through the Great Lakes to the Goldthwait Sea in the Gulf of St. Lawrence basin. Here, we assemble geological evidence from widely scattered localities in and around the Gulf of St. Lawrence, all previously reported, a majority unexplained, and ascribe it collectively to the same climatic cooling. We interpret the marine diamicts and other faunal reversals as the products of cooling, which intensified sea-ice conditions during the interval 10 000-8000 14C yr BP, specifically at 9300 14C yr (9170 yr, reservoir corrected), conditions resulting from that meltwater influx. This age was several centuries too young to be correlated with the Preboreal Oscillation, but several easterly overflows of Lake Agassiz occurred before and after this date, and may have increased sea-ice in the Goldthwait Sea, singly or by hysteresis. Other truly glacial features in southeastern Canada, such as moraine systems and diamictons, are also referred to this cooling.Les spectres polliniques post-glaciaires d’une vaste région du sud-est du Canada montrent que la tendance générale au réchauffement qu’impliquent les changements de végétation régionaux a été interrompue entre 10 000 et 8000 ans 14C BP, revenant à des conditions typiques d’un climat plus froid. Cette inversion biotique a été attribuée à un refroidissement climatique causé par la décharge des eaux froides du lac glaciaire Agassiz, via les Grands Lacs jusqu’à la mer de Goldthwait en passant dans le Golfe du Saint-Laurent. Nous examinons ici plusieurs indices géologiques aux alentours du Golfe du Saint-Laurent, tous déjà publiés, la plupart inexpliqués, et les attribuons collectivement au même refroidissement. Nous interprétons les diamictons marins et les inversions biotiques comme étant le produit d’un refroidissement qui a intensifié les conditions de glace de mers entre 10 000 et 8000 ans BP, plus particulièrement il y a 9300 ans BP (9170 ans, avec correction du réservoir marin), ces conditions résultant des apports d’eau de fonte. Cet âge est trop jeune de plusieurs siècles pour être corrélé à l’oscillation du Préboréal, mais plusieurs épisodes de décharge du lac Agassiz se sont produites avant et après cette date, et peuvent avoir favorisé un plus grand couvert de glace dans la mer de Goldthwait, chacun ou par hystérésis. D’autres traits typiquement glaciaires, tels les systèmes morainiques, sont également associés à ce refroidissement dans le sud-est du Canada

Context, strategy and financial participation: a comparative analysis

This article investigates where financial participation is most likely to be encountered, and explores its compatibility with collective forms of employee voice. It is based on the findings of a major international survey of human resource management (HRM) practices. We found that financial participation was not affected by collective employee voice, but that national context and associated HRM strategies had significant effects on its nature and extent. As financial participation is likely to make for greater variation in wage rates, it tends to weaken industry-level bargaining. By re-casting the fundamental determinants of wages, it is also likely to facilitate greater wage dispersion within the firm. Hence, it was found that financial participation is more commonly encountered in liberal market contexts, and in firms practising calculative HRM, where countervailing employee power is weak, whether or not collective bargaining is formally present

Employee turnover, HRM and institutional contexts.

Literature on comparative capitalism remains divided between approaches founded on stylized case study evidence and descriptions of broad trends, and those that focus on macro data. In contrast, this study explores the relevance of Amable’s approach to understanding differences in employment relations practice, based on firm-level micro data. The article examines employee–employer interdependence (including turnover rates) in different categories of economy as classified by Amable. The findings confirm that exit – whether forced or voluntary – remains more common in market-based economies than in their continental counterparts and that institutionalized employee voice is an important variable in reducing turnover. However, there is as much diversity within the different country categories as between them, and across continental Europe. In Denmark’s case, high turnover is combined with high unionization, showing the effects of a ‘flexicurity’ strategy. While employee voice may be stronger in Scandinavia, interdependence is weaker than in continental Europe

Collective and individual voice: convergence in Europe?

This paper uses longitudinal survey data from Britain, Germany and Sweden to examine whether, as some researchers have suggested, there has been a convergence internationally towards individual forms of employee voice mechanism and, if so, to measure the extent and trajectory of change. The paper begins by examining the importance of the employee voice issue. It then reviews competing accounts of the utility of different forms of employee voice and their manifestations within different varieties of capitalism. It is hypothesized that there has been a general trend away from collective and towards individual voice mechanisms; this reflects the predominant trajectory of managerial practices towards convergence with the liberal market model. This hypothesis is largely rejected. The data showed only very limited evidence of directional convergence towards individual voice models in the three countries. Collective voice remains significant in larger organizations, and although it takes a wide range of forms that include but go beyond unions and works councils, this is a positive finding for proponents of those institutions

Responses to supplementation by dairy cows given low pasture allowances in different seasons 2. Milk production

Two factorial experiments were designed to determine the effects of stage of lactation, and season of the year, on cow responses to supplementary feeding. These experiments were conducted over consecutive years with 128 high genetic merit multiparous Holstein-Friesian cows in early, mid and late lactation in spring, summer, autumn and winter. At each stage of lactation, and in each season of the year, cows were offered a restricted pasture allowance (25 to 35 kg dry matter (DM) per cow per day), either unsupplemented (control) or with supplement at 50 MJ metabolizable energy (ME) per cow per day in experiment 1 and 80 MJ ME per cow per day in experiment 2. The two supplements given in both years were rolled maize grain (MG) and a mixture of foods formulated to nutritionally balance the diet (BR). In experiment 2, another treatment, of a generous pasture allowance (60 to 75 kg DM per cow per day) (AP), was imposed on an additional group of early lactation cows during each season. Direct milk solids (MS) (milk fat plus milk protein) responses in experiment 1 to MG were 169, 279, 195 and 251 g MS per cow per day in spring, summer, autumn and winter, respectively, while those to BR were 107, 250, 192, 289 g MS per cow per day. In experiment 2, however, milk solids responses to both supplements during spring were slightly below the control treatment, with values similar to those in experiment 1 in summer and autumn for cows on the BR but not the MG supplement. Milk solids responses to supplementary foods were largest during seasons of the year when the quantity and quality of pasture on offer resulted in the lowest milk solids yield from unsupplemented cows. When carry-over effects of feeding MG and BR on milk solids production were detected, they were only about half the magnitude of the direct effects. Serum urea concentrations were higher in control cows than those offered MG with a similar effect for BR in all but summer in experiment 1, while serum glucose concentrations were highest in winter and lowest in summer. The most important factor influencing milk solids responses was the relative food deficit (RFD) represented by the decline in milk solids yield of the respective control groups after,changing from a generous pasture allowance to restricted allowance when the feeding treatments were imposed. Total milk solids responses (direct and carry-over) to supplements were greatest when severe food restrictions, relative to the cows' current food demand, resulted in large reductions in milk solids yield of the control groups. The RFD was the best predictor of milk solids response to supplementary foods. Therefore, it is likely that cows are most responsive to supplementary foods during or immediately after the imposition of a severe food restriction