Search results for "Industrial Biotechnology"
showing 10 items of 730 documents
Hazards That Can Affect CNC Machine Tools during Operation—An AHP Approach
2020
CNC (computer numerically controlled) machine tools are highly advanced technological systems, used to machine parts by means of metal cutting processes. Their structure and kinematics are very complex, involving accurate coordinated motions on three to five axes. Operating CNC machine tools is a complicated process, which can easily be affected by errors. Nowadays, safety systems and devices are developed in order to make this process safer and more user friendly. Modern CNC controllers are designed to deal with obvious sources of hazards, such as overloads (by means of various sensor systems) and collisions (by checking the NC code syntax and simulating it on the machine). However, despit…
Effects of heat treatment on hydrogen production potential and microbial community of thermophilic compost enrichment cultures
2011
Cellulosic plant and waste materials are potential resources for fermentative hydrogen production. In this study, hydrogen producing, cellulolytic cultures were enriched from compost material at 52, 60 and 70°C. Highest cellulose degradation and highest H(2) yield were 57% and 1.4 mol-H(2) mol-hexose(-1) (2.4 mol-H(2) mol-hexose-degraded(-1)), respectively, obtained at 52°C with the heat-treated (80°C for 20 min) enrichment culture. Heat-treatments as well as the sequential enrichments decreased the diversity of microbial communities. The enrichments contained mainly bacteria from families Thermoanaerobacteriaceae and Clostridiaceae, from which a bacterium closely related to Thermoanaerobiu…
Hybrid nonlinear observer for Inertial Navigation
2016
This paper considers the problem of designing an observer for navigation and localization of inertial systems. Since the measurement systems used in this field have a low update rate with respect to the control algorithm, the design of a suitable observer with sampled measurements is required. Here a hybrid non-linear observer is proposed, combining two different observers with different characteristics. A theoretical treatment is given in order to prove the convergence of the observer and it will be contextualized in the framework of the hybrid systems, providing an elegant setting for the proposed solution. Finally experimental results show the feasibility of the proposed observer and the…
Visual Servoing Based on Shifted Moments
2015
Over the past decade, image moments have been exploited in several visual servoing schemes for their ability to represent object regions, objects defined by contours or a set of discrete points. Moments have also been useful to achieve control decoupling properties and to choose a minimal number of features to control the whole degrees of freedom (DOFs) of a camera. However, the choice of moment-based features to control the rotational motions around the $x$ -axis and $y$ -axis simultaneously with the translational motions along the same axis remains a key issue. In this paper, we introduce new visual features computed from low-order “shifted moments invariant.” Importantly, they allow us 1…
Experimental design method to the weld bead geometry optimization for hybrid laser-MAG welding in a narrow chamfer configuration
2017
International audience; The work presented in this paper relates to the optimization of operating parameters of the welding by the experimental design approach. The welding process used is the hybrid laser-MAG welding, which consists in combining a laser beam with an MAG torch, to increase the productivity and reliability of the chamfer filling operation in several passes over the entire height of the chamfer. Each pass, providing 2 mm deposited metal and must provide sufficient lateral penetration of about 0.2 mm. The experimental design method has been used in order to estimate the operating parameters effects and their interactions on the lateral penetration on one hand, and to provide a…
Neural networks as effective techniques in clinical management of patients: some case studies
2004
In this paper, we present four examples of effective implementation of neural systems in the daily clinical practice. There are two main goals in this work; the first one is to show that neural networks are especially well-suited tools for solving different kind of medical/pharmaceutical problems, given the complex input output relationships and the few a priori knowledge about data distribution and variable relations. The second goal is to develop specific software applications, which enclose complex mathematical models, to clinicians; thus, the use of such models as decision support systems is facilitated. Four important pharmaceutical problems are considered in this study: identificatio…
Combined fuzzy TOPSIS and AHP-based methodology for the prioritization of maintenance key performance indicators: Application to an oil refinery plant
2017
A Maintenance Performance Measurement model based on the use of Maintenance Key Performance Indicators (MKPIs) is proposed in the present paper. Referring to a specific industrial context, a multi-level hierarchical structure is firstly designed to highlight the most meaningful perspectives which affect the maintenance performance. Then, MKPIs selected from the literature or properly formulated to detail some particular perspective of the investigated maintenance process are assigned to the hierarchical framework and prioritized by a Fuzzy Technique for Order of Preference by Similarity to Ideal Solution (FTOPSIS) and Analytic Hierarchy Process (AHP)-based approach.
An Interactive Demonstration of Collaborative VR for Laparoscopic Liver Surgery Training
2019
We introduce a collaborative virtual reality (VR) system for planning and simulation in laparoscopic liver surgery training. Patient image data is used for surgical model visualization and simulation. We developed two modes for training in laparoscopic procedures: exploration and surgery mode. Surgical joysticks are used in surgery mode to provide training for psychomotor skills and cooperation between a camera assistant and an experienced surgeon. Continuous feedback from our clinical partner comprised an important part of the development. Our evaluation showed that surgeons were positive about the usability and usefulness of the developed system. For further details, please refer to our f…
Collaborative Virtual Reality for Laparoscopic Liver Surgery Training
2019
Virtual reality (VR) has been used in many medical training systems for surgical procedures. However, the current systems are limited due to inadequate interactions, restricted possibilities of patient data visualization, and collaboration. We propose a collaborative VR system for laparoscopic liver surgical planning and simulation. Medical image data is used for model visualization and manipulation. Additionally, laparoscopic surgical joysticks are used to provide an opportunity for a camera assistant to cooperate with an experienced surgeon in VR. Continuous clinical feedback led us to optimize the visualization, synchronization, and interactions of the system. Laparoscopic surgeons were …
Finite-Time Hâ Filtering for T-S Fuzzy Discrete-Time Systems with Time-Varying Delay and Norm-Bounded Uncertainties
2015
In this paper, we investigate the filtering problem of discrete-time Takagi–Sugeno (T–S) fuzzy uncertain systems subject to time-varying delays. A reduced-order filter is designed. With the augmentation technique, a filtering error system with delayed states is obtained. In order to deal with time delays in system states, the filtering error system is first transformed into two interconnected subsystems. By using a two-term approximation for the time-varying delay, sufficient delay-dependent conditions of finite-time boundedness and $H_{\infty }$ performance of the filtering error system are derived with the Lyapunov function. Based on these conditions, the filter design methods are propose…