An on-line respirographic biosensor for the characterization of load and toxicity of wastewaters

A respirographic biosensor is presented that is capable of monitoring the waste load and potential toxicity of wastewaters, both off-line in a laboratory or on-line at the wastewater treatment plant. The principles of the sensors' operation have been developed and implications of the design choices evaluated. Short term BOD values were obtained every 30 min. The linear dynamic range spanned concentrations differing by a factor of 5000. This range could be expanded by a factor of 10 by adjusting the aeration rate of the bioreactor in the sensor. The response time for toxicity detection was approximately 1 h. The use in the sensor of activated sludge from the plant concerned ensured relevant toxicity information was obtained. To check the condition of the sludge, an independent respiration measurement is proposed. When a siginificant activity change is observed, the sludge in the sensor must be replaced. The presence of oxidoreduction chemicals can cause interferences that may lead to measurement errors. Based on a difference in reaction kinetics, their presence can be assessed and the effect eliminated. Both on-line and laboratory applications in the chemical industry are presented. Special emphasis is given to the usefulness of the sensor data for waste management of production divisions. On-line assessment of load variations and hydrogen peroxide spills are given as illustrations of the implementation of the sensor on the treatment plant. Attention is drawn to the potential application of the data for process control and improved performance of the treatment plant.     

The Affinity of Basic Dyes for Leacril 16 Acrylic Fibre

The dyeing affinity of some thiazole and benzothiazole basic azo dyes for Leacril 16 acrylic fibre was measured using Langmuir isotherms. Results show a close dependence of dye structure on affinity.     

On the Ontological Status of Plans and Norms

This article describes an ontological model of norms. The basic assumption is that a substantial part of a legal system is grounded on the concept of agency. Since a legal system aims at regulating a society, then its goal can be achieved only by affecting the behaviour of the members of the society. We assume that a society is made up of agents (which can be individuals, institutions, software programs, etc.), that agents have beliefs, goals and preferences, and that they commit to intentions in order to choose a line of behaviour. The role of norms, within a legal system, is to specify how and when the chosen behaviour agrees with the basic principles of the legal system. In this article, we show how a model based on plans can be the basis for the ontological representation of norms, which are expressed as constraints on the possible plans an agent may choose to guide its behaviour. Moreover, the paper describes how the proposed model can be linked to the upper level of a philosophically well-founded ontology (DOLCE); in this way, the model is set in a wider perspective, which opens the way to further developments.     

An O(nlog n)-SPACE Decision Procedure for the Propositional Dummett Logic

We present a tableau calculus for propositional Dummett logic, also known as LC (Linear Chain), where the depth of the deductions is linearly bounded by the length of the formulas to be proved. We then show that it is possible to decide propositional Dummett logic in O(nlogn)-SPACE.     

Anti-spam legislation: An analysis of laws and their effectiveness

More than half of worldwide e-mail traffic (an estimated total of several billion e-mails per day) consists of spam. This is becoming a considerable disturbance to telecommunications. Spam is also closely related to other kinds of cybercrime as it possibly contains malicious software or is pursuing some kind of fraudulent aim such as phishing. As well as technical and organizational measures, many countries have introduced anti-spam legislation. However, today's worldwide legislative coverage of spam is heterogeneous, and its effectiveness is discussed controversially. This article describes important parameters by which anti-spam legislation can vary and gives an overview and analysis of worldwide anti-spam legislation, including the European Directive 2002/58/EC and the United States CANSPAM Act 2003, and international cooperation, such as the London Action Plan. The article then proceeds to discuss the effectiveness of current laws and identifies problems resulting from the fact that an international phenomenon is being addressed by national legislation. Finally, the article presents suggestions for overcoming some of these problems.     

New bin packing fast lower bounds

In this paper, we address the issue of computing fast lower bounds for the Bin Packing problem, i.e., bounds that have a computational complexity dominated by the complexity of ordering the items by non-increasing values of their volume. We introduce new classes of fast lower bounds with improved asymptotic worst-case performance compared to well-known results for similar computational effort. Experimental results on a large set of problem instances indicate that the proposed bounds reduce both the deviation from the optimum and the computational effort.     

Combined remote-sensing,model, and in situ measurements of sea surface temperature as an aid to recreational navigation: crossing the Gulf Stream

Combined in situ, model, and satellite remote-sensing observations are used to determine the location of the Gulf Stream as an aid to safe navigation for small recreational vessels.

A field study was executed from Hamilton, Bermuda, to Virginia Beach, USA, over a period of 5 days, from 30 June 2010 to 4 July 2010 to test the feasibility of using remote-sensing products as an aid to cross the Gulf Stream from the point of view of a small, slow-moving (?6 knots, 3 m s^?1) sailboat. The in situ data collected were compared to NASA Moderate Resolution Imaging Spectroradiometer (MODIS) and Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) remote-sensing data, to the Global High Resolution Sea Surface Temperature (GHRSST) microwave and infrared blended data set, to the National Oceanic and Atmospheric Administration Real-Time Ocean Forecast System (NOAARTOFS) ocean model, and to selected NOAA buoy and ship measurements.

A spatio-temporal analysis was performed by comparing the in situ measurements with observations retrieved at the same time and location in each of the data sets. The least error (correlation coefficient r?=?0.94) was obtained using MODIS data, and the largest error (r?=?0.78) was obtained using the RTOFS model data. Overall, most observations agree with the general spatio-temporal trend of the in situ data, with 95% of the errors within ±1°C and 98% of the errors within ±2°C.

The study shows that MODIS data are particularly suited to identification of the location of the Gulf Stream, which can be used by small vessels to optimize the crossing route and to minimize the risks associated with the passage.     

Geschichtliche Entwicklung und aktuelle Praxis der Probebelastung — Teil 2: Entwicklung von Normen und heutige Anwendung

Im Zuge des massenhaften Einsatzes von Probebelastungen im 19. und zu Beginn des 20. Jahrhunderts zeigte sich die Notwendigkeit, deren Planung, Durchführung und Auswertung durch allgemeine Richtlinien und Normen zu stützen. Im Beitrag wird das Ringen um erste zaghafte Festlegungen beschrieben, die im Laufe der Jahre immer konkreter zu einer verwendbaren Handlungsgrundlage ausgearbeitet wurden. Unter Kritikern blieb jedoch immer die Frage über die Sicherheit und vor allem die Aussagekraft von Belastungsversuchen auf der Grundlage der verwendeten Bewertungskriterien offen. Mit der Weiterentwicklung der Berechnungsverfahren auch durch den Einsatz von Computertechnik wurden Probebelastungen von Neubauten ab den 1970‐er Jahren entbehrlich. Für auffällig gewordene bestehende Tragwerke stellt die Probebelastung jedoch auch heute noch eine — und manchmal die einzige — Methode zum Nachweis einer ausreichenden Tragfähigkeit dar. Die hierfür angewendete moderne Belastungs‐ und Messtechnologie bietet jedoch im Unterschied zur traditionellen Vorgehensweise ein hohes Maß an Sicherheit und Informationsgewinn. Historical Development and current practise of load tests in situ — Part 2: Development of standards and current practise. Because of the large demand and use of load testing in the 19th and at the beginning of the 20th century, there was the necessity to standardise the planning, execution and analysis in general guidelines and codes. This article describes the struggling and first tentative specification, which were more and more specified to an useful basis in the following years. The used criterions for the assessment have often been a reason for critics on the value and the safety of loading tests. The further development of calculation methods especially the computer technology made the load testing of new structures superfluous in the 1970s. But for existing structures loading tests are today often a — and sometimes the only — method to proof a sufficient load bearing capacity. The today used modern loading‐ and measuring technology provides, in contrast to the traditional method, a high degree of safety and structural information.