Linear Array

A new method for estimation of current-source density (CSD) from local field potentials is presented. This inverse CSD (iCSD) method is based on explicit inversion of the electrostatic forward solution and can be applied to data from multielectrode arrays with various geometries. Here, the method is applied to linear-array (laminar) electrode data. Three iCSD methods are considered: the CSD is assumed to have cylindrical symmetry and be (i) localized in infinitely thin discs, (ii) step-wise constant or (iii) continuous and smoothly varying (using cubic splines) in the vertical direction. For spatially confined CSD distributions the standard CSD method, involving a discrete double derivative, is seen in model calculations to give significant estimation errors when the lateral source dimension is comparable to the size of a cortical column (less than ∼1 mm). Further, discontinuities in the extracellular conductivity are seen to potentially give sizable errors for even wider source distributions. The iCSD methods are seen to give excellent estimates when the correct lateral source dimension and spatial distribution of conductivity are incorporated. To illustrate the application to real data, iCSD estimates of stimulus-evoked responses measured with laminar electrodes in the rat somatosensory (barrel) cortex are compared to estimates from the standard CSD method.

The Archean granites exposed in the Mesorchean Rio Maria granite-greenstone terrane (RMGGT), southeastern Amazonian craton can be divided into three groups on the basis of petrographic and geochemical data. (1) Potassic leucogranites (Xinguara and Mata Surrão granites), composed dominantly of biotite monzogranites that have high SiO 2 , K 2 O, and Rb contents and show fractionated REE patterns with moderate to pronounced negative Eu anomalies. These granites share many features with the low-Ca granite group of the Yilgarn craton and CA2-type of Archean calc-alkaline granites. These granites result from the partial melting of rocks similar to the older TTG of the RMGGT. (2) Leucogranodioritegranite group (Guarantã suite, Grotão granodiorite, and similar rocks), which is composed of Ba-and Sr-rich rocks which display fractionated REE patterns without significant Eu anomalies and show geochemical affinity with the high-Ca granite group or Transitional TTG of the Yilgarn craton and the CA1-type of Archean calc-alkaline granites. These rocks appear to have been originated from mixing between a Ba-and Sr-enriched granite magma and trondhjemitic liquids or alternatively product of interaction between fluids enriched in K, Sr, and Ba, derived from a metasomatized mantle with older TTG rocks. (3) Amphibole-biotite monzogranites (Rancho de Deus granite) associated with sanukitoid suites. These granites were probably generated by fractional crystallization and differentiation of sanukitoid magmas enriched in Ba and Sr. The emplacement of the granites of the RMGGT occurred during the Mesoarchean (2.87e2.86 Ga). They are approximately coeval with the sanukitoid suites (w2.87 Ga) and post-dated the main timing of TTG suites formation (2.98e2.92 Ga). The crust of Rio Maria was probably still quite warm at the time when the granite magmas were produced. In these conditions, the underplating in the lower crust of large volumes of sanukitoid magmas may have also contributed with heat inducing the partial melting of crustal protoliths and opening the possibility of complex interactions between different kinds of magmas.

Geochemically diverse mid-ocean ridge basalts recovered from the Siqueiros Transform Fault, in the east Pacific Ocean, were sulfide-saturated at eruption, on the basis of the presence of immiscible sulfide globules and major and trace element variations of pillow-rim glasses. Previous workers have interpreted, from the chemistry of silicate melt inclusions in olivines which crystallised from liquids more primitive than the erupted basalts, that early Siqueiros liquids were sulfide-undersaturated (e.g., . However, as the composition of these melt inclusions may not represent primary liquid compositions (as discussed by and inclusions of immiscible sulfides occur in the olivines, we interpret that at least some of these liquids were sulfide-saturated early in their fractionation history. The compositions of the immiscible sulfide inclusions in olivine are consistent with those from other MORB suites and estimates of sulfide liquid compositions from mantle rocks (e.g., . Data from the erupted basalts and inclusions provides a well constrained natural dataset that has been combined with experimental data to produce a new sulfide saturation model ) and can be used to test the results of this model.

We have studied the plasmonic properties of aperiodic arrays of identical nanoparticles (NPs) formed by two opposite and equal graded-chains (a chain where interactions change gradually). We found that these arrays concentrate the external electromagnetic fields even in the long wavelength limit. The phenomenon was understood by identifying the system with an effective cavity where plasmonics excitations are trapped between effective band edges, resulting from the change of passband with NP's position. Dependence of excitation concentration on several system's parameter was also assessed. This includes, different gradings as well as NP's couplings, damping, and resonant frequencies. In the spirit of the scaling laws in condensed matter physics, we developed a theory that allows us to rationalize all these system's parameters into universal curves. The theory is quite general and can also be used on many other situations (different arrays for example). Additionally, we also provided an analytical solution, in the tight-binding limit, for the plasmonic response of homogeneous linear chains of NPs illuminated by a plane wave. Our results can find applications on sensing, near field imaging, plasmon-enhanced photodetectors, as well as to increase solar cell efficiency.

Classical and quantum phase transitions involve observables which are non-analytic as functions of a controlled thermodynamical variable. As occurs with the self-consistent Fermi Golden Rule, one condition to obtain the discontinuous behavior is the proper evaluation of a classical or quantum thermodynamic limit. We show that in presence of an environment, the oscillatory dynamics of a quantum two-level system, in analogy with a classical damped oscillator, can undergo a quantum dynamical phase transition to a non-oscillatory phase. This is obtained from a self-consistent solution of the Generalized Landauer Büttiker Equations, a simplified integral form of the Keldysh formalism. We argue that working at each side of the transition implies standing under different paradigms in the Kuhn's sense of the word. In consequence, paradigms incommensurability obtains a sound mathematical justification as a consequence of the non-analyticity of the observables. A strong case is made upon the need to deepen the public's intuition and understanding on the abrupt transition from static to dynamical friction regimes.

Full dimension MIMO (FD-MIMO) is one of the key technologies presently studied in the 3GPP for the next generation long-term evolution advanced (LTE-A) systems. By incorporating FD-MIMO into LTE/LTE-A systems, it is expected that system throughput will be drastically improved beyond what is possible in conventional LTE systems. This paper presets details on the 2D active antenna array design for FD-MIMO systems supporting 32 antenna elements. The FD-MIMO system allows for dynamic and adaptive precoding to be performed jointly across all antennas thus achieving more directional transmissions in the azimuth and elevation domains simultaneously, to a larger number of users. Finally, we discuss 2D antenna array port virtualization techniques for creating beams with wide coverage, necessary for broadcasting signals to all users within a sector, such as the CRS (Common Reference Signal).

Full dimension MIMO (FD-MIMO) is one of the key technologies presently studied in the 3GPP for the next generation long-term evolution advanced (LTE-A) systems. By incorporating FD-MIMO into LTE/LTE-A systems, it is expected that system throughput will be drastically improved beyond what is possible in conventional LTE systems. This paper presets details on the 2D active antenna array design for FD-MIMO systems supporting 32 antenna elements. The FD-MIMO system allows for dynamic and adaptive precoding to be performed jointly across all antennas thus achieving more directional transmissions in the azimuth and elevation domains simultaneously, to a larger number of users. Finally, we discuss 2D antenna array port virtualization techniques for creating beams with wide coverage, necessary for broadcasting signals to all users within a sector, such as the CRS (Common Reference Signal).

In this paper, we proposed a newly modified cuckoo search (MCS) algorithm integrated with the Roulette wheel selection operator and the inertia weight controlling the search ability towards synthesizing symmetric linear array geometry with minimum side lobe level (SLL) and/or nulls control. The basic cuckoo search (CS) algorithm is primarily based on the natural obligate brood parasitic behavior of some cuckoo species in combination with the Lévy flight behavior of some birds and fruit flies. The CS metaheuristic approach is straightforward and capable of solving effectively general N-dimensional, linear and nonlinear optimization problems. The array geometry synthesis is first formulated as an optimization problem with the goal of SLL suppression and/or null prescribed placement in certain directions, and then solved by the newly MCS algorithm for the optimum element or isotropic radiator locations in the azimuth-plane or xy-plane. The study also focuses on the four internal parameters of MCS algorithm specifically on their implicit effects in the array synthesis. The optimal inter-element spacing solutions obtained by the MCS-optimizer are validated through comparisons with the standard CS-optimizer and the conventional array within the uniform and the Dolph-Chebyshev envelope patterns using MATLAB TM . Finally, we also compared the fine-tuned MCS algorithm with two popular evolutionary algorithm (EA) techniques include particle swarm optimization (PSO) and genetic algorithms (GA).

PTCL academy Islamabad In this paper, wide band balanced antenna with enhanced bandwidth performance that covers the 850 to 3000 MHZ of Band, covering the GSM, UMTS, Bluetooth, GPS, & Wi-Fi applications is investigated[1-4]. This antenna was designed in HFSS which have low profile, linear phase and constant radiation pattern with proper return loss and resonant on multiple frequencies. This proposed antenna was then fabricated on substrate FR-4 Epoxy with dimensions 30 x 7 x 1.6 mm, and fed with planer wide band balun to calculate and measure the results.

A version of the iterative Fourier technique (IFT) for the design of thinned antenna arrays with weighted elements is presented. The structure of the algorithm means that it is well suited to the design of weighted thinned arrays with low current taper ratios (CTRs). A number of test problems from the literature are considered, and in each case, the IFT produces results with improved sidelobe level (SLL) at lower CTR.

A version of the iterative Fourier technique (IFT) for the design of thinned antenna arrays with weighted elements is presented. The structure of the algorithm means that it is well suited to the design of weighted thinned arrays with low current taper ratios (CTRs). A number of test problems from the literature are considered, and in each case, the IFT produces results with improved sidelobe level (SLL) at lower CTR.

Under study is an application of Ground Penetrating Radar (GPR) to landmine detection problem. We focus on the detection of antitank mines carried out in the 3D GPR images, so-called C-scans, by means of a machine learning approach. In that approach, we particularly pursue a technique for fast extraction of image features based on an initial calculation of multiple integral images. This allows later to calculate each feature in constant time, regardless of the scanning window position and size. The features we study are statistical moments formulated in their 3D variant. We present a comparison of detection results for different sizes and parameterizations of feature sets. All results are obtained from a prototype GPR system of our original construction in terms of both hardware and software.

The NIST anechoic chamber is used to generate standard (known) EM fields for frequencies from 200 MHz to 40 GHz. The transmitting antennas used are open-ended rectangular waveguides from 200 to 500 MHz and pyramidal horns from 450 MHz to 40 GHz. The uncertainty in the electric field is currently estimated to be ± 1 . dB . A number of changes and additions are planned to improve the accuracy, repeatability, and efficiency of the system.

In this paper the synthesis of linear array geometry with minimum sidelobe level using a new class of Particle Swarm Optimization technique namely Improved Particle Swarm Optimization (IPSO) is described. The IPSO algorithm is a newly proposed, high-performance evolutionary algorithm capable of solving general N-dimensional, linear and nonlinear optimization problems. Compared to other evolutionary methods such as genetic algorithms and

Autonomous off-road navigation is central to several important applications of unmanned ground vehicles. This requires the ability to detect obstacles in vegetation. We examine the prospects for doing so with scanning ladar and with a linear array of 2.2 GHz micro-impulse radar transceivers. For ladar, we summarize our work to date on algorithms for detecting obstacles in tall grass with single-axis ladar, then present a simple probabilistic model of the distance into tall grass that ladar-based obstacle detection is possible. This model indicates that the ladar "penetration depth" can range from on the order of 10 cm to several meters, depending on the plant type. We also present an experimental investigation of mixed pixel phenomenology for a time-of-flight, SICK ladar and discuss briefly how this bears on the problem. For radar, we show results of applying an existing algorithm for multi-frequency diffraction tomography to a set of 45 scans taken with one sensor translating laterally 4 cm/scan to mimic a linear array of transceivers. This produces a high resolution, 2-D map of scattering surfaces in front of the array and clearly reveals a large tree trunk behind over 2.5 m of thick foliage. Both types of sensor warrant further development and exploitation for this problem.

The different techniques to measure and analyze surface EMG are summarized with an emphasis on the clinician's point of view. The application of surface EMG in neurological disease is hampered by many inherent problems, especially the difficulties in extracting features of single motor units. However, the evolution of surface EMG from single bipolar recordings via a linear array of multiple electrodes to densely packed, multi-channel electrode arrays could in principle solve this problem. The added value of using multiple channels (up to 128) with an interelectrode distance of a few millimetres to obtain more spatial information is emphasized. At least for some muscles it is now possible to extract information from the surface EMG, conventionally thought to belong to the domain of needle EMG (for example the "electrical size" of motor units). The use of analysis techniques such as the estimation of muscle fiber conduction velocity has already proven to be of diagnostic value in several myopathies characterized by a disturbed membrane function and in metabolic myopathies with abnormal fatigue profiles. Future research should be directed at the development of analysis techniques enabling the extraction of more relevant motor unit variables from surface EMG signals.

This book provides computer engineers, academic researchers, new graduate students, and seasoned practitioners an end-to-end overview of virtual memory. We begin with a recap of foundational concepts and discuss not only state-of-the-art virtual memory hardware and software support available today, but also emerging research trends in this space. The span of topics covers processor microarchitecture, memory systems, operating system design, and memory allocation. We show how efficient virtual memory implementations hinge on careful hardware and software cooperation, and we discuss new research directions aimed at addressing emerging problems in this space. Virtual memory is a classic computer science abstraction and one of the pillars of the computing revolution. It has long enabled hardware flexibility, software portability, and overall better security, to name just a few of its powerful benefits. Nearly all user-level programs today take for granted that they will have been freed from the burden of physical memory management by the hardware, the operating system, device drivers, and system libraries. However, despite its ubiquity in systems ranging from warehouse-scale datacenters to embedded Internet of Things (IoT) devices, the overheads of virtual memory are becoming a critical performance bottleneck today. Virtual memory architectures designed for individual CPUs or even individual cores are in many cases struggling to scale up and scale out to today's systems which now increasingly include exotic hardware accelerators (such as GPUs, FPGAs, or DSPs) and emerging memory technologies (such as non-volatile memory), and which run increasingly intensive workloads (such as virtualized and/or "big data" applications). As such, many of the fundamental abstractions and implementation approaches for virtual memory are being augmented, extended, or entirely rebuilt in order to ensure that virtual memory remains viable and performant in the years to come.

This paper describes a new method for the synthesis of planar antenna arrays using fuzzy genetic algorithms (FGAs) by optimizing phase excitation coefficients to best meet a desired radiation pattern. We present the application of a rigorous optimization technique based on fuzzy genetic algorithms (FGAs), the optimizing algorithm is obtained by adjusting control parameters of a standard version of genetic algorithm (SGAs) using a fuzzy controller (FLC) depending on the best individual fitness and the population diversity measurements (PDM). The presented optimization algorithms were previously checked on specific mathematical test function and show their superior capabilities with respect to the standard version (SGAs). A planar array with rectangular cells using a probe feed is considered. Included example using FGA demonstrates the good agreement between the desired and calculated radiation patterns than those obtained by a SGA.

Background Endobronchial ultrasound-guided transbronchial needle aspiration is a standard method for obtaining specimens of mediastinal and hilar lesions. Several types of needles of various sizes and materials are available. This study aimed to compare the quality of specimens collected using two needles, cobalt chromium and stainless steel for endobronchial ultrasound-guided transbronchial needle aspiration. Methods This retrospective study included data of patients who underwent EBUS-TBNA with a 22-gauge needle made from either stainless steel (41 lesions, 121 punctures) or cobalt chromium (47 lesions, 145 punctures). Histological data per puncture, diagnostic yield per lesion, procedure time and complication rates were compared. Results There were no significant differences between the groups in the baseline characteristics of the patients or lesions or in the complication rates. The rate of diagnostic histological specimens in each sample (71.0% vs. 58.7%, P = 0.039), fewer sam...

The conventional-trans bronchial needle aspiration (c-TBNA) has been the first procedure for sampling hilar/mediastinal lymph node for the diagnosis/staging of lung cancer. In the last decade the endobronchial ultrasound trans bronchial needle aspiration (EBUS-TBNA) was introduced in clinical practice and became the first-choice exam in diagnosis and staging of lung cancer. The aim of this study was to compare the diagnostic accuracy (DA), sensitivity and adequacy of c-TBNA and EBUS-TBNA. It was a retrospective and observational multicenter study. The first endpoint was diagnostic accuracy of EBUS-TBNA versus c-TBNA. The secondary end-points were sensitivity and adequacy. Two hundred and nine consecutive patients underwent the procedure, 99 EBUS-TBNA and 110 c-TBNA. When lymph nodes with short axis <2 cm the diagnostic accuracy for correct diagnosis was 94.2% in EBUS-TBNA group and 89.7% in c-TBNA group (p=0.01); the sample adequacy was 70.3% and 42%, respectively (p=0.01); the s...

The diagnosis of mediastinal and hilar lymphadenopathy and staging lung cancer with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) are on the rise. Most reports have demonstrated high yields with EBUS-TBNA and superiority of this procedure over conventional TBNA (cTBNA), but the relative roles of these procedures remain undefined. We present a comprehensive comparison of EBUS-TBNA to cTBNA. We reviewed all of the bronchoscopies performed at our medical center from January 2009 through December 2010. We collected data on 82 EBUS-TBNAs and 209 cTBNAs performed. A cost analysis was subsequently performed. Results: EBUS-TBNA was performed more often in patients with known prior cancer and suspicion of recurrence or staging compared with cTBNA (42% vs 18%, P G 0.001). cTBNA was more likely to be performed in patients suspected of having malignancy and needing diagnostic specimens (70% vs 46%, P = 0.009). The overall yield in which a diagnostic specimen or lymphoid tissue was obtained was not different in each group: EBUS 84% vs cTBNA 86% (P = 0.75). The cancer yield was 57% in cTBNAs compared with 44% in EBUS-TBNAs (P G 0.0001), with EBUS-TBNA more often targeting smaller nodes (mean 15 T 7 mm vs 21 T 11 mm; P G 0.0001) and paratracheal sites (67% vs 49%, P = 0.003). Perprocedure cost using a Medicare scale was higher for EBUS than it was for cTBNA ($1195 vs $808; P G 0.001). Conclusions: EBUS-TBNA and cTBNA are complementary bronchoscopic procedures, and the appropriate diagnostic modality can be selected in a cost-effective manner based upon the primary indication for TBNA, lymph node size, and lymph node location.

Rheological models for polymer solutions and melts based on the finitely extensible non-linear elastic (FENE) dumbbell theory are reviewed in this study. The FENE-P model that is a well-known Peterlin approximation of the FENE model, indicates noticeable deviation from original FENE predictions and also experimental results, especially in the transient flow. In addition, both FENE and FENE-P models have some shortcomings from the point of view of theory. To overcome these shortcomings, a new approximation of the FENE spring force has been established. It has been used to develop a modified constitutive rheological model for polymeric fluids. In the procedure of modeling, the effect of non-affine deformation is introduced into the new model. Comparison between the model predictions and experimental data presented in the literature for transient and steady shear flow of polystyrene indicates that this modified model can predict the rheological behavior of polymeric fluids with a great...

University -Fluids used in microfluidic applications often consist of multiple phases, i.e. polymer blends, blood and biological mixtures. One application is the generation of a regular array by the use of T-junctions and flow-focusing devices. In this work, we focus on the pairing and collective dynamics of these trains, and in particular on the influence of the deformability of the dispersed phase, by comparing trains of solid particles and trains of drops. Numerical methods employed are boundary integrals for drops and Stokesian-dynamics techniques for solid particles. We show that isolated pairs of drops undergo pairing, while isolated pairs of rigid spheres do not cluster. By contrast, confined linear arrays of particles and drops always undergo pairing regardless of deformability. Depending on the deformability and the initial separation between the drops, the initial dynamics of the pairing behavior can be quite complex. At prolonged time scales, all drop pairs reach the same velocity, while particle pairs migrate at a different velocity due to different intra-particle distances. In addition, the response of linear arrays to particle displacements shows a qualitative dependence on deformability. For example, drops are self-centering between the bounding walls and therefore linear arrays of drops are more stable to displacements normal to the walls. Complex collective behavior is also observed for linear arrays with particle and drop displacements parallel to the walls.

The method presented in this paper assumes that the received signal is a linear combination of delayed and attenuated uncorrelated replicas of the source emitted waveform. The set of delays and attenuations, together with the channel environmental conditions, provide sufficient information for determining the source location. If the transmission channel is assumed known, the source location can be estimated by matching the data with the acoustic field predicted by the model conditioned on the estimated delay set. This paper presents alternative techniques that do not directly attempt to estimate time delays from the data but, instead, estimate the subspace spanned by the delayed source signal paths. Source localization is then done using a family of measures of the distance between that subspace and the subspace spanned by the replicas provided by the model. Results obtained on the INTIMATE'96 data set, in a shallow-water acoustic channel off the coast of Portugal, show that a sound source emitting a 300-800-Hz LFM sweep could effectively be localized in range or depth over an entire day.

In today's world of wireless communication there is need of antennas having multiband characteristics. This paper presents the design of star shaped slotted rectangular microstrip patch antenna for multiband applications. The star slots are introduced in the geometry of rectangular patch antenna to increase the operating frequency bands to make it a multiband antenna. Proposed antenna is designed on FR4 epoxy substrate having relative permittivity 4.4 and 1.6mm thickness. The resonant frequency used for designing the proposed antenna is 3.2GHz. The proposed antenna works on seven frequency bands such as 3.08GHz, 4.68GHz, 5.67GHz, 5.93GHz, 8.14GHz, 8.46GHz and 9.93GHz. HFSS 13 software is used for designing, simulating and analyzing the different parameters of proposed antenna. The antenna is fabricated and tested. The experimental results are compared with simulated results which are in good agreement with each other

Lavas from the island of Sa ˜o Miguel, Azores Archipelago have long been known to display large radiogenic isotopic variability, that ranges from ''depleted'' isotopic signatures (e.g. high e Nd $ +5) in the west, typical of many ocean island basalts, to more ''enriched '' compositions (e.g. low e Nd $ +1) in the east. Here, we further characterise the geochemistry of lavas from this remarkable locality, focussing on the nature and origin of the enriched source. Our new isotope data define a striking, linear array in Nd and Hf isotope space that points towards an unusual, enriched composition below the mantle array. This distinctive Hf-Nd isotope signature is associated with elevated values of all three radiogenic Pb isotope ratios. Although the enriched component has certain geochemical similarities to both terrigenous sediments and some samples of the continental mantle lithosphere, such comparisons do not stand closer examination. In the absence of a clear, modern analogue we explore the isotope evolution of some simple, model melt compositions to investigate plausible means of producing an appropriate enriched component. Nd-Hf isotope characteristics provide the tightest constraints and can be reproduced by an ancient ($3 Ga), modest-degree melt ($2%) from a garnet peridotite source. Currently, modest-degree melts from garnetbearing sources are found forming some major oceanic islands. Subduction, isolation and later mixing of small amounts (<5%) of such basaltic material with more ubiquitous ambient mantle can account for the isotopic characteristics of the enriched Sa ˜o Miguel source. Yet the incompatible element ratios of the enriched Sa ˜o Miguel lavas do not show ''recycled'' signatures of near-surface alteration nor subduction zone dehydration. Thus, we infer that the enriched component was originally under-plated basalt, intruded into oceanic mantle lithosphere rather than forming the island edifice itself. Since the extreme isotope compositions of Sa ˜o Miguel reflect unextraordinary, albeit ancient, magmatic fractionation, the general rarity of such signatures indicates the efficiency of mantle processes in homogenising or hiding similar sources.

The far-field lobes of the edge elements of a uniformly excited linear array are nearly equal in width to the sidelobes of the array itself, and hence the edge elements are ideal for cancellation of specific sidelobes of the pattern. This supports the concept of partial adaptivity using only the edge elements. This technique is suitable for real-time implementation because only the edge elements require direct control whereas the inner elements are controlled by PROM's. Other advantages are that the nulls produced specifically by control of the edge elements are deep and wide. Also the main beam gain is not much affected by the sidelobe cancellation.

Neuromuscular assessment of rock climbers has been mainly focused on forearm muscles in the literature. We aimed to extend the body of knowledge investigating on two other upper limb muscles during sport-specific activities in nine male rock climbers. We assessed neuromuscular manifestations of fatigue recording surface electromyographic signals from brachioradialis and teres major muscles, using multi-channel electrode arrays. Participants performed two tasks until volitional exhaustion: a sequence of dynamic pull-ups and an isometric contraction sustaining the body at half-way of a pull-up (with the elbows flexed at 90°). The tasks were performed in randomized order with 10 minutes of rest in between. The normalized rate of change of muscle fiber conduction velocity was calculated as the index of fatigue. The time-to-task failure was significantly shorter in the dynamic (31 ±10 s) than isometric contraction (59 ±19 s). The rate of decrease of muscle fiber conduction velocity was found steeper in the dynamic than isometric task both in brachioradialis (isometric: -0.2 ±0.1%/s; dynamic: -1.2 ±0.6%/s) and teres major muscles (isometric: -0.4±0.3%/s; dynamic: -1.8±0.7%/s). The main finding was that a sequence of dynamic pull-ups lead to higher fatigue than sustaining the body weight in an isometric condition at half-way of a pull-up. Furthermore, we confirmed the possibility to properly record physiological CV estimates from two muscles, which had never been studied before in rock climbing, in highly dynamic contractions.

It is shown that the problem of determining the equilibrium shape of bodies formed by freezing of flow in porous medium can be reduced to the Riemann problem with displacement. A solitary body and linear array of bodies are used as examples. Algorithms for determining its boundary is constructed and realized. All results are presented in the graphic form and they correspond to wide diapason of physical parameters.

The problem of estimating the average Conduction Velocity (CV) in the muscle fibers is considered. The velocity is estimated from an array of noisy deterministic and unknown Motor Unit Action Potentials (MUAP) acquired by an array of K co-linear electrodes. In this array a vector of (K-1) independent time delays (TD) are to be estimated. For a given length of the array, the number K has to be determined in order to improve the estimation of the velocity. In this communication we show the influence of the value of K in the CV estimation in presence of noise and changes in the MUAP shape along the array.

Linear arrays of single photon avalanche detectors (SPADs), fabricated using a novel planar process that is compatible with CMOS technology, are presented here. Their suitability for application in fluorescence correlation spectroscopy (FCS) is investigated by examining characteristics such as the dark counting rate, breakdown voltage and quantum efficiency. The problem of optical crosstalk between pixels in the array is investigated and a trench isolation process is proposed to eliminate crosstalk between adjacent pixels in the array.

Elastography is developed as a quantitative approach to imaging linear elastic properties of tissues to detect suspicious tumors. We propose an automatic feature extraction method in ultrasound elastography and echography for characterization of breast lesions. Approach: The proposed algorithm was tested on 40 pairs of biopsy proven ultrasound elastography and echography images of which 11 are cystic, 16 benign and 13 malignant lesions. Ultrasound elastography and echography images of breast tissue are acquired using Siemens (Acuston Antares) ultrasound scanner with a 7.3 MHz linear array transducer. The images were preprocessed and subjected to automatic threshold, resulting in binary images. The contours of a breast tumor from both echographic and elastographic images were segmented using level set method. Initially, six texture features of segmented lesions are computed from the two image types followed by computing three strain and two shape features using parameters from segmented lesions of both elastographic and echographic images. Results: These features were computed to assess their effectiveness at distinguishing benign, malignant and cystic lesions. It was found that the texture features extracted from benign and cystic lesions of an elastogram are more distinct than that of an ultrasound image .The strain and shape features of malignant lesions are distinct from that of benign lesions, but these features do not show much variation between benign and cystic lesions. Conclusion: As strain, shape and texture features are distinct for benign, malignant and cystic lesions, classification of breast lesions using these features is under implementation.

This paper presents an optical implementation for fully shuffled trees (fsts). The fsts are hierarchical interconnection networks for parallel and massively parallel systems. They have the advantages of high fault tolerance, scalability, and adaptability to any basic processor element (pe) clusters. The optical bus based fully shuffled trees' (obfsts) implementation is based on inverting the fst graph and the use of optical buses to interconnect communication processors at different levels of the tree. In comparison with other optical based interconnection networks, the obfst has lower end-to-end delays and a lower number of i/o ports or optical connections per processor than the I-dimensional, 2dimensional optical arrays or the linear array of reconfigurable pipelined bus (larpb). Also, each obfst optical bus may have a constant number of processors irrespective of the system size.

To assess the ability of the color Doppler twinkling artifact to detect renal stones relative to acoustic shadowing, we scanned seven uric acid calculi embedded in a tissue mimicking phantom and in sheep kidneys using a high frequency linear array and a standard curved linear array ultrasound scanheads (L12-5 and C5-2; Philips Ultrasound, Bothel, WA, USA). The stones were scanned in and out of focus. The scans were optimized for shadow formation in gray-scale imaging and for color twinkling in color Doppler imaging. The images were analyzed using Image J (). We calculated the contrast to noise ratios (C/N) for the acoustic shadows and the color twinkling artifact compared with background. These measurements were then evaluated using a single factor analysis of variance (ANOVA) and paired two-tailed t tests. With these comparisons, the C/Ns for twinkling were significantly higher than for acoustic shadowing. On average, twinkling produced 19.2 dB greater C/Ns for stones in the phantom and 17.6 dB more for the stones in the kidneys. In addition, ANOVA showed that twinkling is resistant to focusing and scanning frequency differences. The results suggest that the twinkling artifact is a robust method for detecting the presence of renal calculi. The color signature is easier to detect than is acoustic shadowing. Twinkling may be relatively resistant to many of the problems that plague ultrasound examinations for renal stones, i.e., out-of-focus scans that might be caused by beam aberration effects due to patient body habitus.

Low-cost linear arrays of deflectable micromirrors using a CMOS-compatible process to define both on-chip circuitry and the mirror structure are presented. The mirrors consist of the CMOS second metal layer deposited In two successive passes in order to establish a thick metal layer for the stiff mirror plate as well as a thin one for the flexible hinges. The mirrors are released by sacrificial aluminum and oxide etch• Ing. Supercritical point drying is performed in order to avoid sticking of the mirrors lo the substrate. The mirrors are electrostatically deflected by biasing the address electrodes implanted inlo the substrate underneath the mirror plate. Full angular deflection by ::4.8 deg of a 30 x 40-µrn 2 plate is achieved with a driving voltage of 11 V. On-chip circuitry adjacent to each mirror allows one to address the pixels with 5-V data pulses. The reflectance of the aluminum surface for wavelengths between 400• and 700 nm was measured to be 83% to 89°<>. The mirror surface was further characterized using Auger spectroscopy, showing that no optically rel• evant surface modifications occur during postprocessing. The surface rms roughness measured by atomic force microscopy is on the order of 2 5 nm. ll:I