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91.
Peter A. Vanrolleghem Zaide Kong Guido Rombouts Willy Verstraete 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,59(4):321-333
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. 相似文献
92.
93.
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. 相似文献
94.
J. Francisco Duque-Carrillo Juan M. Carrillo Guido Torelli José L. Ausín 《Analog Integrated Circuits and Signal Processing》2004,40(1):21-29
In this paper, a circuit technique—common-mode (CM) response overlapping—for maintaining the small-signal behavior of rail-to-rail amplifiers nearly constant over the whole input CM range, is introduced. This technique modifies the CM response of the rail-to-rail input stage adequately by means of two constant input floating voltage sources, which are adjusted by using a static tuning section. Its performance is compared with a second technique—CM response shaping—, which is also based on two variable input floating voltage sources, but relies on a dynamic feedback tuning loop. Experimental results obtained from two 3-V 0.8-m CMOS single-stage rail-to-rail amplifiers, which operate with CM response overlapping and shaping, respectively, are provided. 相似文献
95.
Guido?BoellaEmail author Leonardo?Lesmo Rossana?Damiano 《Artificial Intelligence and Law》2004,12(4):317-357
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. 相似文献
96.
Friedl-Vallon F Maucher G Seefeldner M Trieschmann O Kleinert A Lengel A Keim C Oelhaf H Fischer H 《Applied optics》2004,43(16):3335-3355
MIPAS-B2 is a balloon-borne limb-emission sounder for atmospheric research. The heart of the instrument is a Fourier spectrometer that covers the mid-infrared spectral range (4-14 microns) and operates at cryogenic temperatures. Essential for this application is the sophisticated line-of-sight stabilization system, which is based on an inertial navigation system and is supplemented with an additional star reference system. The major scientific benefit of the instrument is the simultaneous detection of complete trace gas families in the stratosphere without restrictions concerning the time of day and viewing directions. The specifications, the design considerations, the actual realization of the instrument, and the results of characterization measurements that have been performed are described. 相似文献
97.
Massimo Gottardi Lorenzo Gonzo Stefano Gregori Valentino Liberali Andrea Simoni Guido Torelli 《Analog Integrated Circuits and Signal Processing》2003,34(2):143-154
This paper presents a front-end circuit for optical rotary encoders. The light pulses modulated by the encoder disc are transduced into current signals, which are pre-processed and converted into digital waveforms related to the disc angular position information. The proposed front-end circuit is compensated against temperature drifts. Digitally programmable calibration is provided to account for spreads in impinging light pulse power. Measurement results on integrated prototypes are shown, demonstrating correct operation of the front-end with an optical input power from 0.5 W to 3 W up to a signal frequency of 500 kHz in a temperature range from 0 °C to 80 °C. 相似文献
98.
Debora?FinoEmail author Paolo?Fino Guido?Saracco Vito?Specchia 《Korean Journal of Chemical Engineering》2003,20(3):445-450
The development of catalytic means for the regeneration of particulate-laden traps for diesel exhaust cleaning is the main
topic of this paper. All the steps of the catalytic trap preparation are dealt with, including: the synthesis and choice of
the proper catalyst and trap materials, the development ofin situ catalyst deposition, and the bench testing of the derived catalytic traps. Two different traps were considered (i.e., silicon
carbide and cordierite wallflow monoliths operating via a shallow-bed filtration mechanism), whereas the best catalyst selected
was the perovskite LaCr0.9O3. The filtration efficiency and the pressure drops of the catalytic and non-catalytic monoliths were evaluated on a diesel
engine bench under various operating conditions. On the basis of the obtained results the catalysed SiC converter was found
to be the most satisfactory converter to be placed on the exhaust line of the modern common rail diesel-engine cars. 相似文献
99.
Guido Fiorino 《Journal of Automated Reasoning》2001,27(3):297-311
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. 相似文献
100.
Guido Schryen 《Information & Communications Technology Law》2007,16(1):17-32
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. 相似文献