Log-based transactional workflow mining

A continuous evolution of business process parameters, constraints and needs, hardly foreseeable initially, requires a continuous design from the business process management systems. In this article we are interested in developing a reactive design through process log analysis ensuring process re-engineering and execution reliability. We propose to analyse workflow logs to discover workflow transactional behaviour and to subsequently improve and correct related recovery mechanisms. Our approach starts by collecting workflow logs. Then, we build, by statistical analysis techniques, an intermediate representation specifying elementary dependencies between activities. These dependencies are refined to mine the transactional workflow model. The analysis of the discrepancies between the discovered model and the initially designed model enables us to detect design gaps, concerning particularly the recovery mechanisms. Thus, based on this mining step, we apply a set of rules on the initially designed workflow to improve workflow reliability. The work presented in this paper was partially supported by the EU under the SUPER project (FP6-026850) and by the Lion project supported by Science Foundation Ireland under Grant No. SFI/02/CE1/I131.     

Electronic band structure and spin-density maps of SmCo5

We present first-principles calculations on SmCo₅ using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method. We systematically study the effect of considering the spin–orbit coupling and Coulomb correlations in the Sm f shell on the magnetic properties, electronic structure and spin-density maps. The calculated magnetic moment and magnetocrystalline anisotropy are in good agreement with experimental values when the LDA + U + SO scheme is used. This confirms the adequacy of using this scheme in SmCo₅. The spin-density maps in the (0 0 1) plane show that the effect of the spin–orbit coupling on the spin-density structure of Sm atoms is stronger than that of Coulomb correlation. The reverse however, is true for Co atoms. We also study the influence of the magnetization direction on the energy bands through comparing the features of band structure when magnetization direction is along or perpendicular to the c-axis.     

Mass production of CNTs using CVD multi-quartz tubes

Carbon nanotubes (CNTs) have become the backbone of modern industries, including lightweight and heavy-duty industrial applications. Chemical vapor deposition (CVD) is considered as the most common method used to synthesize high yield CNTs. This work aims to develop the traditional CVD for the mass production of more economical CNTs, meeting the growing CNT demands among consumers by increasing the number of three particular reactors. All reactors housing is connected by small channels to provide the heat exchange possibility between the chambers, thereby decreasing synthesis time and reducing heat losses inside the ceramic body of the furnace. The novel design is simple and cheap with a lower reacting time and heat loss compared with the traditional CVD design. Methane, hydrogen, argon, and catalyzed iron nanoparticles were used as a carbon source and catalyst during the synthesis process. In addition, CNTs were produced using only a single quartz tube for comparison. The produced samples were examined using XRD, TEM, SEM, FTIR, and TGA. The results showed that the yield of CNTs increases by 287 % compared with those synthesized with a single quartz tube. Moreover, the total synthesis time of CNTs decreases by 37 % because of decreased heat leakage.

     

Thermal conductivity and thermal boundary resistance of nanostructures

   

We present a fabrication process of low-cost superlattices and simulations related with the heat dissipation on them. The influence of the interfacial roughness on the thermal conductivity of semiconductor/semiconductor superlattices was studied by equilibrium and non-equilibrium molecular dynamics and on the Kapitza resistance of superlattice's interfaces by equilibrium molecular dynamics. The non-equilibrium method was the tool used for the prediction of the Kapitza resistance for a binary semiconductor/metal system. Physical explanations are provided for rationalizing the simulation results.     

A low-power oriented architecture for H.264 variable block size motion estimation based on a resource sharing scheme

In the Advanced Video Coding (AVC) standard, motion estimation (ME) adopts many new features to increase the coding performances such as block matching algorithm (BMA), motion vector prediction (MVP) and variable block size motion estimation (VBSME). However, VBSME is utilized in the MPEG4-AVC/H.264 standard which leads to high computational complexity and data dependency that make the hardware implementation very complex.     

Learning from hint for the conservative motion of the constrained industrial redundant manipulators

A neural network (NN)-based kinematic inversion of industrial redundant arms is developed in this paper to conserve the joint configuration in cyclic trajectories. In the developed approach, the Widrow–Hoff NN with an online adaptive learning algorithm derived by applying Lyapunov approach is introduced. Since this kinematic inversion has an infinite number of joint angle vectors, a fuzzy neural network system is designed to provide an approximate value for that vector. Feeding this vector as an additional hint input vector to the NN limits and guides the output of the NN within the self-motion of the manipulator. The derivation of the candidate Lyapunov function, which is designed to achieve the joint configurations conservation in addition to the joint limits avoidance, leads to a computationally efficient online learning algorithm of the NN. Simulations are conducted for the PA-10 redundant manipulator to bear out the efficacy of the developed approach for tracking closed trajectories.     

Integration of dialysis membranes into a poly(dimethylsiloxane) microfluidic chip for isoelectric focusing of proteins using whole-channel imaging detection

A poly(dimethylsiloxane) microfluidic chip-based cartridge is developed and reported here for protein analysis using isoelectic focusing (IEF)-whole-channel imaging detection (WCID) technology. In this design, commercial dialysis membranes are integrated to separate electrolytes and samples and to reduce undesired pressure-driven flow. Fused-silica capillaries are also incorporated in this design for sample injection and channel surface preconditioning. This structure is equivalent to that of a commercial fused-silica capillary-based cartridge for adapting to an IEF analyzer (iCE280 analyzer) to perform IEF-WCID. The successful integration of dialysis membranes into a microfluidic chip significantly improves IEF repeatability by eliminating undesired pressure-driven hydrodynamics and also makes sample injection much easier than that using the first-generation chip as reported recently. In this study, two microfluidic chips with a 100-microm-high, 100-microm-wide and a 200-microm-high, 50-microm-wide microchannel, respectively, were applied for qualitative and quantitative analysis of proteins. The mixture containing six pI markers with a pH range of 3-10 was successfully separated using IEF-WCID. The pH gradient exhibited a good linearity by plotting the pI value versus peak position, and the correlation coefficient reached 0.9994 and 0.9995 separately for the two chips. The separation of more complicated human hemoglobin control sample containing HbA, HbF, HbS, and HbC was also achieved. Additionally, for the quantitative analysis, a good linearity of IEF peak value versus myoglobin concentration in the range of 20-100 microg/mL was obtained.     

Novel Green Synthesis of Zinc Oxide Nanoparticles Using Orange Waste and Its Thermal and Antibacterial Activity

Journal of Inorganic and Organometallic Polymers and Materials - Zinc oxide nanoparticles (ZnO NPs) prepared via eco-friendly synthesis (using orange peels) are investigated. Pseudomonas Aeruginosa...     

SoTCM: a scene-oriented task complexity metric for gaze-supported teleoperation tasks

Recent developments in human–robot interaction (HRI) research have heightened the need to incorporate indirect human signals to implicitly facilitate intuitive human–guided interactions. Eye-gaze has been widely used nowadays as an input interface in multi-modal teleoperation scenarios due to their advantage in revealing human intentions and forthcoming actions. However, to date, there has been no discussion about how the structure of the environment, that the human is interacting with, could affect the complexity of the teleoperation task. In this paper, a new metric named “Scene-oriented Task Complexity Metric” (SoTCM) is proposed to estimate the complexity of a certain scene that is involved in eye-gaze-supported teleoperation tasks. The proposed SoTCM objectively estimates the effort that could be exerted by the human operator in terms of the expected time required to point at all the informative locations retrieved from the scene under discussion. The developed SoTCM depends on both the density and distribution of the informative locations in the scene, while incorporates the eye movement behavior found in the psychology literature. The proposed SoTCM is subjectively validated by using the time-to-complete index in addition to the standard (NASA-TLX) workload measure in eight varying structure scenes. Results confirmed a significant relation between SoTCM and the measured task workload which endorses the applicability of using SoTCM in predicting scene complexities and subsequently the task workload in advance.