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71.
A new extraction method for source series resistance and mobility reduction coefficient with transverse field, based on the MOSFET transconductance modeling in the saturation region, is reported. The simple associated transconductance model also appears to be extremely useful for optimal parameter extraction. The proposed method is validated on partially depleted SIMOX MOSFETs.  相似文献   
72.
A double-gate (DG) fin field effect transistor (FinFET) is discussed as new label-free ion and biological sensor. Simulations as function of channel doping, geometrical dimensions, operation point and materials investigated the device response to an external potential difference which provides a body threshold voltage modulation. The simulation results presented in this work clearly state the key features for an ultrasensitive FET based sensor: an enhancement low doped and partially gated transistor operating in weak-moderate inversion regime. The optimized sensitivity, obtained when the width of the fin is equal to the gate height (wNW ∼ hg), reaches a value of 85% for an extraction current, Id, of 0.1 μA. These results pave the way for the fabrication process of an innovative CMOS compatible sensing system.  相似文献   
73.
This paper presents our method, which simultaneously combines automatic imaging, identification, and counting with the acquisition of morphological information for at least 1000 blood cells from several three-dimensional images of the same sample. We started with seeking parameters to differentiate between red blood cells that are similar but different with respect to their development stage, i.e., mature or immature. We highlight that these cells have different diffractive patterns with complementary central intensity distribution in a given plane along the propagation axis. We use the Fresnel approximation to simulate propagation through cells modeled as spheroid-shaped phase objects and to find the cell property that has the dominant influence on this behavior. Starting with images obtained in the reconstruction step of the digital holographic microscopy technique, we developed a code for automated simultaneous individual cell image separation, identification, and counting, even when the cells are partially overlapped on a slide, and accurate measuring of their morphological features. To find the centroids of each cell, we propose a method based on analytical functions applied at threshold intervals. Our procedure separates the mature from the immature red blood cells and from the white blood cells through a decision based on gradient and radius values.  相似文献   
74.
Noma (Cancrum Oris/Ulcerogingivostomstitis) is a rare devastating grangrenous orofacial disease. It may lead to severe facial mutilation and deformities with dysfunctional effects. This disease primarily affects malnourished children from underdeveloped countries. It has recently been associated with AIDS in North America and Western Europe. We will be reporting and discussing the pathogenesis, bacteriological complications and treatments according to the literature.  相似文献   
75.
Results obtained in the pulse irradiation tests performed on segmented fuel elements in the Romanian Annular Core Pulse Reactor (ACPR) are discussed below. Tests included the effects of initial element internal pressure and a wide range of energy deposition on the fuel element behavior. All tests were conducted in stagnant water at room temperature and atmospheric pressure inside the capsule. The fuel elements were instrumented with thermocouples for cladding surface temperature measurement. Transient histories of reactor power, cooling water pressure, fuel element internal pressure and cladding temperature were recorded during the tests. The fuel elements were subjected to total energy depositions from 70 to 265 cal g−1 UO2. Cladding failure mechanism and the failure threshold have been established. The fuel failure mechanism is a burst type and is very similar to LOCA failure mechanism even though the rate energy deposition is higher in the ACPR tests. At higher energy deposition brittle cladding fracture near endcap weld region can be produced. The failure threshold is situated between 190 and 200 cal g−1 UO2 for standard fuel rod (0.2–0.3 MPa internal pressure) and less than 160 cal g−1 UO2 for pressurized fuel rods (internal pressure between 1 and 3.0 MPa). Pre-pressurization could be an important factor to control the failure threshold energy. The experimental program is still in progress and new experiments are foreseen to be performed in the following period.  相似文献   
76.
In this correspondence, first-tier indirect (direct) discernible constellation expansions are defined for generalized orthogonal designs. The expanded signal constellation, leading to so-called super-orthogonal codes, allows the achievement of coding gains in addition to diversity gains enabled by orthogonal designs. Conditions that allow the shape of an expanded multidimensional constellation to be preserved at the channel output, on an instantaneous basis, are derived; this property, referred to as fading resilience, is first discussed in the context of quasi-static fading, then generalized to coordinate interleaved transmissions for rapid fading. In both cases - and despite of piecing together (in the latter case) a constellation point as a result of coordinate deinterleaving - the channel alters neither the relative distances nor the angles between signal points in a fading-resilient signal constellation. It is shown that nonorthogonal MIMO constellations having a geometric structure that is resilient to fading do exist, and their further study is warranted.  相似文献   
77.
Behaviour model control (BMC) is known to increase the robustness of a process control. It has already been applied to electrical drives for single-loop controls. This paper introduces the BMC among others model control strategies and extends its single-loop structure to more complex controls, which need several loops. This extension is applied to a double loop control of a DC machine drive. Simulations and experimental results show that the suggested double-loop BMC yields better results than a classical control, increasing robustness against parameter variations and external disturbances.  相似文献   
78.
Based on the so-called generalized Popov-Yakubovich theory the well-known formula of the least achievable tolerance for the “two block problem” is easily recovered in a self-contained way.  相似文献   
79.
This paper reports on the design and implementation of an expert system for computer process control (HESCPC). The complexity of the expertise necessary for computer process control applications requires that the expert system architecture be structured into a hierarchy of classes of specialized experts. The architecture of HESCPC integrates four classes of expert systems: operator/manager companion expert class, control system algorithm design expert class, hardware expert class, and software expert class. The paper is concerned with the design and implementation of the general system architecture, an operator adviser expert for a nuclear power plant and a control system designer expert using a state space feedback approach. Although the design and implementation aspects of all experts are discussed, the emphasis is on the latter.

At this stage of the HESCPC development, the declarative knowledge represented by 423 metarules and 1261 rules is distributed on a hierarchical structure among 20 experts on different levels of the hierarchy which are able to communicate among themselves to solve difficult control problems.

Examples of control system design sessions of linear mono and multivariable systems using feedback state space approach are given. A run time of an operator-adviser data-driven expert system for a nuclear plant is also presented.  相似文献   

80.
A clinical and experimental study was carried out on knee joints of rabbits and in humans. In one knee joint of each rabbit 0.3 ml 1% osmic acid or 0.3 ml 5% Varicocid was injected, the remaining uninjected joints serving as controls. The animals were killed after 1 and 24 hours, 15, 45 and 90 days. Study with the electron microscope after osmic acid injection revealed necrosis of the chondrocytes in the superficial layer and upper middle zone. The articulations injected with Varicocid exhibited only slight lesions of the chondrocytes in the upper layer, consisting of dilated rough endoplasmatic reticulum, mitochondria lacking matrix and christae; the electron density of the layer seemed to be diminished. Biopsy of the non-weight-bearing cartilage of the lateral femoral condyle was performed in 4 patients with Rheumatoid Arthritis and arthritis of the knee in the onset stage. Two of these patients received one intra-articular injection of 10 ml 1% osmic acid, 5 ml 2% xylocaine and 50 mg hydrocortisone and the other 2 patients 6 ml 5% Varicocid. Biopsy of the cartilage in the areas adjacent to the site of the first biopsies 1 and 3 1/2 months after treatment with osmic acid and 2 and 3 1/2 months after treatment with Varicocid showed in the first two cases necrosis of the chondrocytes in the superficial layer and upper middle zone of the articular cartilage and depletion of the mucopolysaccharides in the ground substance, revealed by PAS and alcian blue staining. No lesion of the knee joint cartilage was observed in the other two cases. In view of the results obtained, chemical synovectomy with Varicocid can be considered as having received further support.  相似文献   
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