Semi-automated user agents in distributed change management

Flexible integration of distributed design and manufacturing activities is one of the key issues in applying just-in-time principles along the logistics chain. The potential of AI based approaches in this field is clear, but the inherent asynchrony, concurrency, and inconsistency of distributed operations has reduced enthusiasm so far.This paper discusses coordination in the context of geographically distributed manufacturing of one-of-a-kind products. Cooperation of partners is based on semi-automated user agents which operate as an integrative layer between more dedicated tools and systems. The management of order changes in elevator manufacture is used as a case example.The work reported here is part of the DIMUN project (DIMUN, 1989) in the RACE program.     

Unambiguous atomic structural determination of single-walled carbon nanotubes by electron diffraction

We introduce a novel non-dimensional “intrinsic layer-line spacing” concept for electron diffraction analysis of single-walled carbon nanotubes (SWCNTs). Accordingly, we develop a unique method for direct determination of chiral indices (n, m) of the carbon nanotubes from their electron diffraction patterns (EDPs). The new method is totally calibration-free. Errors due to the nanotube inclination are specified. The tilt angle of the carbon nanotube with respect to the incident electron beam is simultaneously evaluated, thus the effect of the tube tilting is compensated for in the (n, m) determination. Several effective procedures are proposed to cross-check the results by using abundant information contained in the diffraction patterns. The efficiency of the method is demonstrated on both simulated and experimental diffraction patterns from single-walled nanotubes. The technique can be extended to structural analysis of nanotubes of structure similar to carbon nanotubes, such as boron nitride nanotubes.     

Physical Violence Detection Based on Distributed Surveillance Cameras

Mobile Networks and Applications - In recent years, physical violence detection has become a research hotspot in the area of human activity recognition. With the improvement and full coverage of...     

Bridging the physical and virtual worlds by local connectivity-based physical selection

The prevalent visions of ambient intelligence emphasise natural interaction between user and functions and services embedded in the environment or available through mobile devices. In these scenarios the physical and virtual worlds seamlessly gear into each other, making crossing the border between these worlds natural or even invisible to the user. The bottleneck in reaching these scenarios appear in the natural mapping between the physical objects and their virtual counterparts. The emergence of local connectivity in mobile devices opens possibilities for implementing novel user interface paradigms to enhance this mapping. We present physical selection paradigm for implementing an intuitive human technology interaction for mobile devices. In order to demonstrate the feasibility of the paradigm we implemented two experimental set-ups using commercially available smart phones with IrDA connectivity. The experiments involved selecting a website by physically pointing at its symbol and making a phone call by pointing at an icon representing the person to be called. In tentative user experiments the physical selection method was more time-efficient and it was perceived more positively by the users than a conventional method.

A method for transforming grammars into LL(k) form

Summary A new method for transforming grammars into equivalent LL(k) grammars is studied. The applicability of the transformation is characterized by defining a subclass of LR(k) grammars, called predictive LR(k) grammars, with the property that a grammar is predictive LR(k) if and only if the corresponding transformed grammar is LL(k). Furthermore, it is shown that deterministic bottom-up parsing of a predictive LR(k) grammar can be done by the LL(k) parser of the transformed grammar. This parsing method is possible since the transformed grammar always left-to-right covers the original grammar. The class of predictive LR(k) grammars strictly includes the class of LC(k) grammars (the grammars that can be parsed deterministically in the left-corner manner). Thus our transformation is more powerful than the one previously available, which transforms LC(k) grammars into LL(k) form.     

Maximal and minimal representations of gapped and non-gapped motifs of a string

The problems of finding maximal and minimal equivalent representations for gapped and non-gapped motifs as well as finding motifs that characterize a fixed set of occurrence locations for a given string are studied. We apply two equivalence relations on representations. The first one is the well-known occurrence-equivalence of motifs. The second equivalence is introduced for patterns of occurrence locations, to characterize such patterns by motifs. For both equivalences, quadratic-time algorithms are given for finding a maximal representative of an equivalence class. Finding a minimal representative is shown to be NP-complete in both cases. For non-gapped motifs suffix-tree-based linear-time algorithms are given for finding maximal and minimal representatives. Maximal (minimal) gapped motifs are composed of blocks that are maximal (minimal) non-gapped motifs, maximal and minimal non-gapped motifs thus making up a small basis for all motifs. The implied bound on the number of gapped motifs that have a fixed number of non-gapped blocks is also given.     

Carbon nanotubes and onions from carbon monoxide using Ni(acac)2 and Cu(acac)2 as catalyst precursors

New catalyst precursors (copper and nickel acetylacetonates) have been used successfully for the synthesis of carbon nanotubes and onion particles from carbon monoxide. Catalyst nanoparticles and carbon products were produced by metal-organic precursor vapour decomposition and catalytic disproportionation of carbon monoxide in a laminar flow reactor at temperatures between 705 and 1216 °C. Carbon nanotubes (CNTs) were formed in the presence of nickel particles at 923-1216 °C. The CNTs were single-walled, 1-3 nm in diameter and up to 90 nm long. Hollow carbon onion particles (COPs) were produced in the presence of copper particles at 1216 °C. The COPs were from 5 to 30 nm in diameter and consisted of several concentric carbon layers surrounding a hollow core. The results of computational fluid dynamics calculations to determine the temperature and velocity profiles and mixing conditions of the species in the reactor are presented. The mechanisms for the formation of both CNTs and COPs are discussed on the basis of the experimental and computational results.     

Smoke gas analysis by Fourier transform infrared spectroscopy – summary of the SAFIR project results

The determination of toxic components from fire gases is difficult because the environment is hot, reactions are often temperature dependent, and a lot of soot may be produced. Due to the different properties of the gas components, a different time‐consuming procedure for each species has traditionally been used. The use of FTIR (Fourier transform infrared) spectrometers as a continuous monitoring technique overcomes many of the problems in smoke gas analyses. FTIR offers an opportunity to set up a calibration and prediction method for each gas showing a characteristic spectral band in the infrared region of the spectrum. The objective of the SAFIR project was to further develop the FTIR gas analysis of smoke gases to be an applicable and reliable method for the determination of toxic components in combustion gases related to fire test conditions. The optimum probe design, filter parameters and the most suitable sampling lines in terms of flow rate, diameter, construction material and operating temperature have been specified. In the large scale, special concern was given to the probe design and the effects of the probe location as well as practical considerations of the sampling line length. Quantitative calibration and prediction methods have been constructed for different components present in smoke gases. Recommendations on how to deal with interferents, non‐linearities and outliers have been provided and a verification method for the spectrometer for unexpected variations and for the different models have been described. FTIR measurement procedures in different fire test scenarios have been studied using the recommendations of this project for measurement techniques and analysis and an interlaboratory trial of the FTIR technique in smoke gas analysis was carried out to define the repeatability and reproducibility of the method in connection with a small scale fire test method, the cone calorimeter. Copyright © 2000 John Wiley & Sons Ltd.     

Direct synthesis of carbon nanofibers on the surface of copper powder

A novel approach to synthesize carbon nanofibers (CNFs) directly on the surface of metal μm-sized particles to evenly disperse the carbon nanomaterials in a composite material was proposed. As a metal matrix, 5–10 μm copper particles were utilized. As a carbon source, C₂H₂, CH₄ and CO were examined. The best conditions were found to be in C₂H₂ (30 cm³/min) and H₂ (260 cm³/min) atmosphere at the temperature of 750 °C. The composites based on copper and CNFs prepared by vacuum hot pressing showed the increase in hardness from 35 to 60 kg/mm² almost retaining pure copper electrical properties.