On the design of dynamic associative neural memories

We consider the design problem for a class of discrete-time and continuous-time neural networks. We obtain a characterization of all connection weights that store a given set of vectors into the network, that is, each given vector becomes an equilibrium point of the network. We also give sufficient conditions that guarantee the asymptotic stability of these equilibrium points.     

Using heuristic algorithms for capacity leasing and task allocation issues in telecommunication networks under fuzzy quality of service constraints

Nowadays, every firm uses telecommunication networks in different amounts and ways in order to complete their daily operations. In this article, we investigate an optimisation problem that a firm faces when acquiring network capacity from a market in which there exist several network providers offering different pricing and quality of service (QoS) schemes. The QoS level guaranteed by network providers and the minimum quality level of service, which is needed for accomplishing the operations are denoted as fuzzy numbers in order to handle the non-deterministic nature of the telecommunication network environment. Interestingly, the mathematical formulation of the aforementioned problem leads to the special case of a well-known two-dimensional bin packing problem, which is famous for its computational complexity. We propose two different heuristic solution procedures that have the capability of solving the resulting nonlinear mixed integer programming model with fuzzy constraints. In conclusion, the efficiency of each algorithm is tested in several test instances to demonstrate the applicability of the methodology.     

Geometric stabilization of bearing races by centerless rolling

The geometric stabilization of bearing races by centerless rolling is studied experimentally, for the outer races of ball bearings.     

Engineering of the Fluorescent‐Energy‐Conversion Arm of Phi29 DNA Packaging Motor for Single‐Molecule Studies

The bacteriophage phi29 DNA packaging motor contains a protein core with a central channel comprising twelve copies of re‐engineered gp10 protein geared by six copies of packaging RNA (pRNA) and a DNA packaging protein gp16 with unknown copies. Incorporation of this nanomotor into a nanodevice would be beneficial for many applications. To this end, extension and modification of the motor components are necessary for the linkage of this motor to other nanomachines. Here the re‐engineering of the motor DNA packaging protein gp16 by extending its length and doubling its size using a fusion protein technique is reported. The modified motor integrated with the eGFP‐gp16 maintains the ability to convert the chemical energy from adenosine triphosphate (ATP) hydrolysis to mechanical motion and package DNA. The resulting DNA‐filled capsid is subsequently converted into an infectious virion. The extended part of the gp16 arm is a fluorescent protein eGFP, which serves as a marker for tracking the motor in single‐molecule studies. The activity of the re‐engineered motor with eGFP‐gp16 is also observed directly with a bright‐field microscope via its ability to transport a 2‐µm‐sized cargo bound to the DNA.     

The basal concentration and characteristics of the diurnal secretory rate of prolactin in women with primary hypothyroidism]

Basal concentration was measured of prolactin (PRL) as were its diurnal fluctuations in blood depending on the clinical association of primary hypothyrosis (PH) with lactorrhea-amenorrhea, lactorrhea only or lactorrhea associated with disturbances in menstrual and reproductive functions that differ from those in amenorrhea, and without such disturbances. Patients with lactorrhea-amenorrhea syndrome present with continual hyperprolactinemia and no physiological diurnal rythm of PRL secretion. In patients presenting without amenorrhea, and basal hyperprolactinemia, lactorrhea and disordered menses result from transitory "night-time" hyperprolactinemia. PH patients who do not present with lactorrhea and disordered menstrual and reproductive function show physiological diurnal rythm of PRL secretion, with its parameters corresponding to those in healthy women. The development of hyperprolactinemia in PH is not age-related; neither is it associated with severity of hypothyrosis.     

Micromechanical detection of proteins using aptamer-based receptor molecules

We report label-free protein detection using a microfabricated cantilever-based sensor that is functionalized with DNA aptamers to act as receptor molecules. The sensor utilizes two adjacent cantilevers that constitute a sensor/reference pair and allows direct detection of the differential bending between the two cantilevers. One cantilever is functionalized with aptamers selected for Taq DNA polymerase while the other is blocked with single-stranded DNA. We have found that the polymerase-aptamer binding induces a change in surface stress, which causes a differential cantilever bending that ranges from 3 to 32 nm depending on the ligand concentration. Protein recognition on the sensor surface is specific and has a concentration dependence that is similar to that in solution.     

A fuzzy model based adaptive PID controller design for nonlinear and uncertain processes

We develop a novel adaptive tuning method for classical proportional–integral–derivative (PID) controller to control nonlinear processes to adjust PID gains, a problem which is very difficult to overcome in the classical PID controllers. By incorporating classical PID control, which is well-known in industry, to the control of nonlinear processes, we introduce a method which can readily be used by the industry. In this method, controller design does not require a first principal model of the process which is usually very difficult to obtain. Instead, it depends on a fuzzy process model which is constructed from the measured input–output data of the process. A soft limiter is used to impose industrial limits on the control input. The performance of the system is successfully tested on the bioreactor, a highly nonlinear process involving instabilities. Several tests showed the method's success in tracking, robustness to noise, and adaptation properties. We as well compared our system's performance to those of a plant with altered parameters with measurement noise, and obtained less ringing and better tracking. To conclude, we present a novel adaptive control method that is built upon the well-known PID architecture that successfully controls highly nonlinear industrial processes, even under conditions such as strong parameter variations, noise, and instabilities.     

Comparative evaluation of 3D vs. 2D modality for automatic detection of facial action units

Automatic detection of facial expressions attracts great attention due to its potential applications in human–computer interaction as well as in human facial behavior research. Most of the research has so far been performed in 2D. However, as the limitations of 2D data are understood, expression analysis research is being pursued in 3D face modality. 3D can capture true facial surface data and is less disturbed by illumination and head pose. At this junction we have conducted a comparative evaluation of 3D and 2D face modalities. We have investigated extensively 25 action units (AU) defined in the Facial Action Coding System. For fairness we map facial surface geometry into 2D and apply totally data-driven techniques in order to avoid biases due to design. We have demonstrated that overall 3D data performs better, especially for lower face AUs and that there is room for improvement by fusion of 2D and 3D modalities. Our study involves the determination of the best feature set from 2D and 3D modalities and of the most effective classifier, both from several alternatives. Our detailed analysis puts into evidence the merits and some shortcomings of 3D modality over 2D in classifying facial expressions from single images.     

Influence of residual deformation after abrasive machining and centrifugal finishing on ball-bearing assembly

Experimental data are presented regarding the influence of residual deformation after abrasive machining and centrifugal finishing on ball-bearing assembly.