贝卡尔特公司的专利产品SiroLock(R)——一种能有效握持纤维的工作辊及道夫用新型针布

贝卡尔特公司推出一种在非织造和传统纺纱长纤罗拉梳理机上道夫和工作辊用的新型针布SiroLock(R).这种高效针布的独特设计使纤维的握持和转移控制达到了一个全新的水平,从而大大提高了纤网的质量及梳理机的产能.     

Gate-defined confinement in bilayer graphene-hexagonal boron nitride hybrid devices

We report on the fabrication and measurement of nanoscale devices that permit electrostatic confinement in bilayer graphene on a substrate. The graphene bilayer is sandwiched between hexagonal boron nitride bottom and top gate dielectrics. Top gates are patterned such that constrictions and islands can be electrostatically induced. The high quality of the devices becomes apparent from the smooth pinch-off characteristics of the constrictions at low temperature with features indicative of conductance quantization. The islands exhibit clear Coulomb blockade and single-electron transport.     

Oligomerization of propene on an alumoxane-grafted MCM-41 host with bis(cyclopentadienyl)zirconium dimethyl (Cp2Zr(CH3)2)

The anchoring of alumoxane, synthesized by the in situ hydrolysis of trimethylaluminum, on the internal pore walls of a mesoporous MCM-41 support generates a highly active and selective host for bis(cyclopentadienyl)zirconium dimethyl (Cp₂Zr(CH₃)₂) in the oligomerization of propene. The regioselective preference of the immobilized metallocene is preserved and a typical Flory–Schulz distribution for the propene oligomers is obtained. This revised version was published online in July 2006 with corrections to the Cover Date.     

Characterization of Escherichia coli from raw poultry in Belgium and impact on the detection of Campylobacter jejuni using Bolton broth

A comparative study examining Bolton broth and Preston broth for enrichment and reliable detection of Campylobacter jejuni (both healthy and freeze stressed cells) was performed. Tested as pure cultures, Bolton broth enabled faster resuscitation and growth of C. jejuni compared to Preston broth. When C. jejuni was co-incubated with extended-spectrum-beta-lactamase (ESBL) producing Escherichia coli isolated from Belgian poultry meat preparations, the latter dominated in the Bolton enrichment broth and crowded the mCCDA plates. This resulted in the inability to recover C. jejuni by ISO 10272-1:2006 standard method. Preston broth did not support the growth of the ESBL E. coli isolates, but showed longer detection time of C. jejuni compared to Bolton broth. The use of the same antibiotic (sodium cefoperazone) in Bolton broth and in mCCDA plates may explain the problems encountered for detection of C. jejuni, as high numbers of ESBL E. coli present after enrichment in Bolton broth, also caused overgrowth and masked the few C. jejuni colonies present on the mCCDA plates. The use of Campylobacter spp. specific real-time PCR circumvented these problems and enabled rapid detection of the pathogen after 24 h enrichment in both Bolton and Preston broth, for both healthy and freeze stressed cells.     

Feature selection by genetic algorithms in object-based classification of IKONOS imagery for forest mapping in Flanders, Belgium

Obtaining detailed information about the amount of forest cover is an important issue for governmental policy and forest management. This paper presents a new approach to update the Flemish Forest Map using IKONOS imagery. The proposed method is a three-step object-oriented classification routine that involves the integration of 1) image segmentation, 2) feature selection by Genetic Algorithms (GAs) and 3) joint Neural Network (NN) based object-classification. The added value of feature selection and neural network combination is investigated. Results show that, with GA-feature selection, the mean classification accuracy (in terms of Kappa Index of Agreement) is significantly higher (p < 0.01) than without feature selection. On average, the summed output of 50 networks provided a significantly higher (p < 0.01) classification accuracy than the mean output of 50 individual networks. Finally, the proposed classification routine yields a significantly higher (p < 0.01) classification accuracy as compared with a strategy without feature selection and joint network output. In addition, the proposed method showed its potential when few training data were available.     

N-dimensional versus (N–1)-dimensional connectivity testing of first-order queries to semi-algebraic sets

This paper addresses the question whether one can determine the connectivity of a semi-algebraic set in three dimensions by looking only at two-dimensional “samples” of the set, where these samples are defined by first-order queries. The question is answered negatively for two classes of first-order queries: cartesian-product-free, and positive one-pass. Floris Geerts is Post-doctoral researcher of the FWO-Vlaanderen. Hasselt University is a partner in the transnationale Universiteit Limburg; the authors belong to the School voor Informatietechnologie.     

Stabilization of Free Lime in BOF Slag by Melting and Solidification in Air

The present study reports on the mineralogy of BOF slag after melting and solidification under Ar and air atmosphere. Results indicate that free lime can be effectively stabilized in air without additional stabilizers like SiO₂. The stabilization mechanism was analyzed, and the role of the oxygen partial pressure was explored. Wustite is believed to be oxidized to hematite under high oxygen partial pressure and then stabilizes the free lime by forming brownmillerite.     

Forecasting broadband Internet adoption on trains in Belgium

Thanks to the massive success of mobile access devices such as netbooks or Apple’s iPhone 3G, Internet on the move has become one of the prominent features of today’s information society. With the emergence of wireless and mobile communication networks, the railroad industry is now catching up on this new technology in their battle with low-cost operators to bring more productivity and entertainment possibilities to its passengers. With millions of daily commuters as potential service users, this transport branch offers high business opportunities. However, while most field trials and research effort have mainly focused on the enabling technology, little research effort has been conducted to forecast the demand-side. This article tries to fill this gap by presenting original results gathered from a large-scale survey amongst 1324 regular train travellers. By means of the Product Specific Adoption Potential method, we predict the potential market penetration of wireless Internet services onboard trains and estimate the size and nature of five adopter segments in terms of socio-demographics, drivers and thresholds, willingness to pay, applications and quality of service. We will discuss the practical implications of these insights in order to develop viable business models, set up introduction strategies and build out user-driven infrastructure networks.     

Investigating the influence of QoS on personal evaluation behaviour in a mobile context

The efficiency of personal video suggestions generated by recommender systems is highly dependent on the quality of the obtained user feedback. This feedback has to reflect the personal interest in the content of the viewed video, to obtain accurate results. However, user feedback might undesirably be influenced by additional aspects such as the loading speed or the quality of the video. To date, this issue has received very little research attention. Therefore, this study investigates the direct influence of audio-visual quality parameters on explicit user feedback for the first time to our knowledge via a mobile, Living Lab experiment. This paper proposes a feedback model which takes the Quality of Service (QoS) parameters of the mobile network into account. This model can be used as an additional feedback filter for video recommendation systems that could help to eliminate the influences of QoS on explicit user feedback.