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This paper addresses dynamic positioning of surface vessels moored to the seabed via a turret-based spread mooring system, referred to as position mooring. Different options relevant for construction of automatic control schemes for the thruster system are first discussed based on consideration of relevant loss functions. In particular, the role of structural reliability criteria applied to the mooring system is addressed. A control algorithm based on such reliability criteria is introduced. The structural reliability measure becomes an intrinsic part of the controller, automatically adjusting the allowed motion limits based on current weather conditions and structural properties of the mooring lines. The performance of this control system is subsequently demonstrated both by numerical simulations and laboratory experiments on a model vessel.

Electrolytic conductivity measurements at the Danish Institute of Fundamental Metrology (DFM), the United States National Institute of Standards and Technology (NIST), and the Hungarian National Office of Measures (OMH) were compared using solutions of potassium chloride in water with nominal conductivities of 10 mS/m, 100 mS/m, and 1 S/m at 25 °C. Each participant determined the conductivities of the solutions by the method of their choice and reported uncertainties that were calculated according to the Guide to the Expression of Uncertainty in Measurement of the International Organization for Standardization (ISO). Secondary methods were used. The values determined by each institute for all three solutions agree within the stated uncertainties reported by the participants.

On June 28, 1993, the EU Commission adopted the Regulation on Environmental Management and Auditing (the EMA scheme) allowing voluntary participation by companies in the industrial sector. The scheme provides for the set up of an environmental policy, the establishment of an environmental management system including internal audit, the submission of an environmental statement to the public and the verification of this by an independent environmental verifier. Certain major problems areas have already been identified which could jeopardise the success of the EMA scheme. This article deals with a crucial, and maybe overlooked, potential problem area, namely that the environmental statement and the controlling function will be of insufficient quality if the EMA scheme is perceived and implemented in the same way as Quality Standards (e.g. ISO 9000 or BS 5750).

The article discusses potential causes of a tight “budgetary squeeze” in Norwegian central cities. The dependent variable, financial stress, is measured as the ratio of expenditure growth as compared to the growth of tax revenues. Budgetary stress turns out to be positively correlated with the centrality (measured by a set of indicators) of the cities. This finding is analyzed by means of path‐analysis. The bivariate relation is decomposed in a week, direct effect of centrality, and indirect effects mediated through the municipal activity‐level, the local revenues and expenditure needs generated by an elderly population. Political competition and fragmentation do not influence the dependent variable significantly, nor do bad housing conditions explain any of the correlation between centrality and financial stress.

Lipid peroxidation and decrease in chlorophyll-a and chlorophyll-b content in Scenedesmus cells was followed in the course of time. Addition of diquat to the algae in the light causes lipid peroxidation and a decrease in chlorophyll content. This decrease is mainly due to chlorophyll-a, the concentration of chlorophyll-b remains more or less constant during the experiment. In the presence of N′-(3,4-dichlorophenyl)-NN-dimethylurea (DCMU), of cysteine, or during nitrogen-flushing of the algal suspension, the lipid peroxidation caused by diquat is strongly suppressed. The decrease in chlorophyll-a content caused by diquat is somewhat smaller in the presence of DCMU or during nitrogen-flushing than with diquat alone, but is not influenced by cysteine. The chemical antioxidant butylated hydroxytoluene does not affect lipid peroxidation and chlorophyll destruction caused by diquat.

The application of potentiometric stripping analysis to sea water for the determination of Pb, Cd and Zn has been demonstrated. The precision was evaluated by several duplicate determinations and was found to be in the range of 5–16% relative, depending on the concentration level. The accuracy of the method was evaluated by comparison with other conventional methods, i.e., atomic absorption spectroscopy and anodic stripping voltammetry, and good agreement was found. Where statistical comparisons could be performed between the methods, no significant difference was found.

Purified suspensions of Coxsackie B5 virus and swine vesicular disease virus (SVDV) were prepared by harvesting and purifying cell pack virus. Crossed immunoelectrophoresis was carried out with purified N and H antigen fractions (full and empty particles). Relative migration velocity (RMV) was calculated for the N antigen fraction of 3 SVD viruses (UKG72, HK71 and Italy 66) and 2 Coxsackie B5 viruses (Faulkner and 8068). The prototype strain of Coxsackie B5 virus (Faulkner) had a low RMV almost identical to that of the first isolated strain of SVDV, Italy 66. A recent isolate of Coxsackie B5 virus (8068, isolated in UK in 1973) had a relatively high RMV very close to that of the UKG72 strain of SVDV isolated in the UK in 1972. Also the Hong Kong strain of SVDV (HK71) had a high RMV value. These observations are considered in relation to the emergence of swine vesicular disease.