Development of an internet and fuzzy based control system of manufacturing process

The aim of this work is to develop an Internet and fuzzy based control and data acquisition system for an industrial process plant which can ensure remote running and fuzzy control of a cement factory. Cases studies of the proposed system application in three cement factories in Algeria, SCAEK (Setif), SCIMAT (Batna), and SCT (Tebessa), are discussed. The remote process control consists of alarms generated during running of the processes while maintaining and synchronizing different regulation loops thus ensuring automatic running of processes smoothly. In addition, fuzzy control of the kiln and the other two mills ensures that the system is operational at all times with minimal downtime. The process control system contains different operator station (OP), alarms table and a provision to monitor trends analysis. The operator can execute any operation according to his authorised access assigned by the system administrator using user administration tool. The Internet technology is used for human security by avoiding all times presence of operators at site for maintenance. Further, in case of a breakdown, the problem would be remotely diagnosed and resolved avoiding requirement of an expert on site thus eliminating traveling cost, security risks, visa formalities, etc. These trips are difficult to organize (costs, visas, risks). So the enterprise can reduce downtimes and travel costs. In order to realize a process control system guided by operators in the main control room or through Internet, the process control is based on programming in PCS 7 utilizing Cemat library and Fuzzy Control++ Siemens tools.     

Shortest Length Paths for a Differential Drive Robot Keeping a set of Landmarks in Sight

This paper studies the local nature of the shortest length paths for a differential drive robot, in the presence of two or more landmarks that the robot has to keep in its field of view. Such a system has to satisfy several types of constraint: the non-holonomy, the bounds on the sensor angle and a visibility constraint for the landmarks. We study the shape of the configuration space resulting from these constraints, the particular spiral-like curves (that we call S-curves) resulting from maintaining the sensor angle to its saturation values, and finally we provide a local analysis of the shortest length paths for this system, that involves these S-curves. We give a more general characterization of the shortest length paths for a set of N landmarks to be kept in sight. Finally, we describe a randomized planner that is based on these local primitives and for which we present planning simulations. The main application of this work can be found in the surveillance area, which is of special interest in present days for most Latin American metropolis.     

Bioconversion of shrimp shell waste for the production of antioxidant and chitosan used as fruit juice clarifier

The pH, proteolytic activity, extent of demineralisation and deprotenisation of shrimp waste were studied during 7 days of fermentation using Pseudomonas aeruginosa A2. After 3 days, pH dropped from 7.0 to 4.4 and then remained constant. Simultaneously, a demineralisation of 92% was achieved. However, protease activity reached its highest level (1230 U mL^?1) after 1 day of incubation, and a protein removal of 90% was achieved. Chitin obtained was converted to chitosan. This chitosan, with 73% deacetylation, was tested for clarification of different fruit juices. It was observed that low concentrations of chitosan (below to 1%) greatly increase the clarity of juices without affecting the nutritional value. The antioxidant activity of the hydrolysates produced during fermentation was tested. Hydrolysate obtained after 3 days showed the strongest scavenging activity (90%), which was comparable to the positive control BHA; however, that obtained after 1 day exhibited the highest ferric‐reducing antioxidant power (OD 700 nm = 1.7).     

Theoretical Investigations of Hysteresis Loops of Ferroelectric or Ferrielectric Nanotubes with Core/Shell Morphology

In this paper, the hysteresis behavior of the nanotubes, consisting of a ferroelectric core of spin-1/2 surrounded by a ferroelectric shell of spin-1/2 with ferro- or anti-ferroelectric interfacial coupling is studied by using the transverse Ising model (TIM). Based on a probability distribution method, the effective field theory has been used to examine the effects of the interfacial coupling constant, the transverse field, and the temperature on the hysteresis loops of the nanotubes. A number of characteristic behaviors have been found, such as the existence of triple hysteresis loops for appropriate values of the system parameters. The remanent polarization and the coercive field, as functions of the temperature, are examined.     

Low molecular weight serine protease from the viscera of sardinelle (Sardinella aurita) with collagenolytic activity: Purification and characterisation

A new low molecular weight (LMW) serine-protease from sardinelle (Sardinella aurita) viscera was purified using ammonium sulphate precipitation and Sephadex G-100 gel filtration, with a 3.82-fold increase in specific activity. The molecular weight of the enzyme was estimated to be 14.2 kDa by SDS-PAGE. The optimum pH and temperature for the enzyme activity were around pH 8.0 and 60 °C, respectively. The purified protease was strongly inhibited by phenylmethylsulphonyl fluoride, a serine-protease inhibitor, and soybean trypsin inhibitor. The N-terminal amino acid sequence of the first 10 amino acids of the purified protease was APVQPCVVVI. This sequence showed low homology with several peptidases, suggesting that the enzyme is a new protease. Interestingly, the protease was found to cleave collagen type I and hydrolyze succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide (sAAPFpna), an amide substrate of chymotrypsin. Our findings indicate that the S. aurita protease is a new LMW enzyme with collagenolytic activity.     

Estimation of SiC JFET temperature during short-circuit operations

This paper presents results showing the robustness of different SiC JFET transistors from SiCED in current limitation regime or short-circuit operation. Crystal temperature during failure was estimated after different electrical characterizations and using appropriate models of saturation current which is used as a thermal indicator. This work shows the exceptional robustness of SiC JFET transistors in current limitation mode compared to Si devices (MOSFETS and IGBTs).     

The effect of nano-sized BNBT on microstructure and dielectric/piezoelectric properties

(Bi_0.5Na_0.5)_0.94Ba_0.06TiO₃ (abbreviated as BNBT6) ceramic of near MPB composition was synthesized by two different processes. The first one is the addition of pre-synthesized BaTiO₃ and pre-milled Bi₂O₃, Na₂CO₃, BaCO₃ powders and calcination powder milled with a high energy milling machine in order to obtain a nano-particle size. The second one is a conventional one to compare with the former process. The pre-milling and the pre-synthesis process of raw materials lowered the calcination temperature to the extent of 59 °C as compared with conventionally fabricated BNBT6. The particle size of the powder exposed to heavy high energy milling reduced to 50–70 nm, whereas that of the conventionally ball-milled powder without the pre-milling and the pre-synthesis process had a larger size of 280 nm. To investigate the effects of the modified process on the characteristic of BNBT6 ceramics, the dielectric and the piezoelectric properties of sintered specimens fabricated by the two different processes were evaluated. It was found that the properties of the nano-sized BNBT6 ceramic near the MPB composition were increased by the modified mixing and milling method, showing superior characteristics in terms of the piezoelectric/dielectric constant and sintering density compared with those of the conventional process. The modified mixing and milling method was considered to be a new and promising process for lead-free piezoelectric ceramics owing to their excellent piezoelectric/dielectric properties.     

Compact size ultrasonic linear motor using a dome shaped piezoelectric actuator

This paper presents original results obtained in the development of dome-shaped actuator for a linear motor application. The main structure of compact ultrasonic linear motor presented in this paper consists of three parts, which were an actuating part, a shaft and mobile element. The actuating part was fabricated by powder injection molding (PIM) process. The linear motion of new-type linear motor was operated by the principle of inertia displacement. The actuating part combined with clamping ceramic element can be realized by the central movement of dome-shaped piezoelectric actuator (DSPA), which has the maximum displacement of the up-and-down movement. The linear motor, where DSPA was 9.86?mm in diameter, 4.6?mm in curvature of radius and 0.4?mm in thickness, operated at 1^st resonance frequency. The dynamic characteristics of the motor was investigated by finite element method (FEM) and compared with experimental results. These results were in good agreement with that predicted by simulations.     

Motion priors based on goals hierarchies in pedestrian tracking applications

In this paper, the problem of automated scene understanding by tracking and predicting paths for multiple humans is tackled, with a new methodology using data from a single, fixed camera monitoring the environment. Our main idea is to build goal-oriented prior motion models that could drive both the tracking and path prediction algorithms, based on a coarse-to-fine modeling of the target goal. To implement this idea, we use a dataset of training video sequences with associated ground-truth trajectories and from which we extract hierarchically a set of key locations. These key locations may correspond to exit/entrance zones in the observed scene, or to crossroads where trajectories have often abrupt changes of direction. A simple heuristic allows us to make piecewise associations of the ground-truth trajectories to the key locations, and we use these data to learn one statistical motion model per key location, based on the variations of the trajectories in the training data and on a regularizing prior over the models spatial variations. We illustrate how to use these motion priors within an interacting multiple model scheme for target tracking and path prediction, and we finally evaluate this methodology with experiments on common datasets for tracking algorithms comparison.