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Time domain methods, while well suited to compute the steady state behaviour of strongly nonlinear non-autonomous electrical circuits, are inefficient if the periods of the forcing signals have a very large minimum common multiple. The solution of the periodicity constraint requires to integrate the differential algebraic equation (DAE) describing the circuit along the T period and this can be a CPU time consuming task. Literature reports several attempts to extend the SH method to simulate circuits driven by multi-tone signals [2] [4] [5]. However, as far as we know, all they suffer of limitations and it is our opinion that an efficient and general extension has not been found, yet. In this paper we present a possible extension that takes its origin from the previous approach reported in [2]. In this paper a modification of the conventional shooting method is presented that tries to overcome the above drawback.

FastSpice techniques are considered in this paper and in particular partitioning methods that split a large circuit in a set of smaller sub-circuits to quickly and accurately compute a dc solution. Each sub-circuit contributes to a set of Jacobian matrices with reduced dimensions that are more efficiently LU-factorised during the iterations of the solving methods. As a matter of fact, the numerical effort required by factorisation is a non linear (polynomial) function of the matrix dimension. We describe the use of voltage and current probes that can be inserted to “virtually” tear nodes and branches of the original circuit to further improve circuit splitting. The proposed techniques do not alter the accuracy of the simulation and thus we obtain FastSpice performances while keeping Spice accuracy. This can be a key issue in simulating circuits designed with deep-submicron technologies. Simulation performances of the proposed approach are compared with those of modern commercial full-chip FastSpice and Spice -like simulators.

Multiple myeloma (MM) remains an incurable disease, with little information available on its management in real-world clinical practice. The results of the present prospective, noninterventional observational study revealed great diversity in the treatment regimens used to treat MM. Our results also provide data to inform health economic, pharmacoepidemiologic, and outcomes research, providing a framework for the design of protocols to improve the outcomes of patients with MM. Background: The present prospective, multinational, noninterventional study aimed to document and describe real-world treatment regimens and disease progression in multiple myeloma (MM) patients. Patients and Methods: Adult patients initiating any new MM therapy from October 2010 to October 2012 were eligible. A multistage patient/site recruitment model was applied to minimize the selection bias; enrollment was stratified by country, region, and practice type. The patient medical and disease features, treatment history, and remission status were recorded at baseline, and prospective data on treatment, efficacy, and safety were collected electronically every 3 months. Results: A total of 2358 patients were enrolled. Of these patients, 775 and 1583 did and did not undergo stem cell transplantation (SCT) at any time during treatment, respectively. Of the patients in the SCT and non-SCT groups, 49%, 21%, 14%, and 15% and 57%, 20%, 12% and 10% were enrolled at treatment line 1, 2, 3, and ≥ 4, respectively. In the SCT and non-SCT groups, 45% and 54% of the patients had received bortezomib-based therapy without thalidomide/lenalidomide, 12% and 18% had received thalidomide/lenalidomide-based therapy without bortezomib, and 30% and 4% had received bortezomib plus thalidomide/lenalidomide-based therapy as frontline treatment, respectively. The corresponding proportions of SCT and non-SCT patients in lines 2, 3, and ≥ 4 were 45% and 37%, 30% and 37%, and 12% and 3%, 33% and 27%, 35% and 32%, and 8% and 2%, and 27% and 27%, 27% and 23%, and 6% and 4%, respectively. In the SCT and non-SCT patients, the overall response rate was 86% to 97% and 64% to 85% in line 1, 74% to 78% and 59% to 68% in line 2, 55% to 83% and 48% to 60% in line 3, and 49% to 65% and 36% and 45% in line 4, respectively, for regimens that included bortezomib and/or thalidomide/lenalidomide. Conclusion: The results of our prospective study have revealed great diversity in the treatment regimens used to manage MM in real-life practice. This diversity was linked to factors such as novel agent accessibility and evolving treatment recommendations. Our results provide insight into associated clinical benefits. © 2018 The Authors

An electro-mechanical model of a SF 6 circuit breaker for medium voltage applications, i.e. for voltages up to 36 kV and short circuit currents up 50 kA is presented. The model is developed by starting from the well known Schwarz-Advonin arc model with the addition of the mechanical effects on the arc geometry and of the “puffer”. The puffer can blow the arc during its full duration and mainly during current zero crossing to extinguish it. This action is carefully exploited by breaker designers and often is the key aspect to obtain arc extinction in high current conditions.

In the near future Electrical Vehicless (EVs) will most likely replace conventional combustion-engine based ones. This and the increase in the use of renewable energy sources will have an important positive impact on our ecosystem. At the same time it will require a serious reanalysis and possibly redesign of the structure of our distribution network. In this paper we propose a model that, at a relatively fine level, describes the behavior of communities in terms of transport requirements, derives statistic driving behavior patterns and determines the corresponding induced Electric Vehicle Charging habits. The energy consumption of every simulated EV is computed taking into account the features of the trip and the vehicle itself. The model has been tailored to data extracted from a portion of the Milan (Italy) metropolitan area, but is trivially adaptable to any area for which a similar set of data is available. The obtained results are compared to data from similar works, showing good agreement. The outputs of the model, i.e. the energy consumption of the vehicles and their time-spatial distribution within a specific area (and consequently the loads on the distribution network nodes due to charging operations), have been (and will be) used to perform impact analyses on network performances and on personal mobility.

The activity of NF-kappa B/Rel nuclear factors is known to inhibit apoptosis in various cell types. We investigated whether the subtraction of NF-kappa B/Rel activity influenced the response of 11 AML (M1, M2 and M4) patients' cells to AraC. To this end we used a phosphorothioate double-stranded decoy oligodeoxynucleotide (ODN) carrying the NF-kappa B/Rel- consensus sequence. Cell incubation with this ODN, but not its mutated (scrambled) form used as a control, resulted in abating the NF-kappa B/Rel nuclear levels in these cells, as verified by electrophoretic mobility shift assay (EMSA) of cells' nuclear extracts. We incubated the leukemic cells with AraC (32 or 1 microM), in either the absence or presence of the decoy or the scrambled ODN, and analyzed cell apoptosis. The spontaneous cell apoptosis detectable in the absence of AraC (25%) was not modulated by the oligonucleotide presence in cell cultures. On the other hand, in 10 of the 11 samples tested, the decoy kappa B, but not the scrambled ODN significantly (P0.01 in a Student's t test) enhanced cell apoptotic response to AraC. Such an effect was particularly remarkable at low AraC doses (1 microM). These findings indicate that NF-kappa B/Rel activity influences response to AraC in human primary myeloblastic cells, and suggests that the inhibition of NF-kappa B/Rel factors can improve the effect of chemotherapy in AML. Gene Therapy (2000) 7, 1234-1237.

Item does not contain fulltext The faster hematopoietic recovery after autologous peripheral blood SCT (APBSCT) in patients with AML may be offset by an increased relapse risk as compared with autologous BMT (ABMT). The EORTC and GIMEMA Leukemia Groups conducted a trial (AML-10) in which they compared, as second randomization, APBSCT and ABMT in first CR patients without an HLA compatible donor. A total of 292 patients were randomized. The 5-year DFS rate was 41% in the APBSCT arm and 46% in the ABMT arm with a hazard ratio (HR) of 1.17; 95% confidence interval=0.85-1.59; P=0.34. The 5-year cumulative relapse incidence was 56% vs 49% (P=0.26), and the 5-year OS 50% and 55% (P=0.6) in the APBSCT and ABMT groups, respectively. APBSCT was associated with significantly faster recovery of neutrophils and platelets, shorter duration of hospitalization, reduced need of transfusion packed RBC and less days of intravenous antibiotics. In both treatment groups, higher numbers of mobilized CD34+ cells were associated with a significantly higher relapse risk irrespective of the treatment given after the mobilization. Randomization between APBSCT and ABMT did not result in significantly different outcomes in terms of DFS, OS and relapse incidence.

Subsidy reduction and the increased importance of photovoltaic energy generation have triggered the need to develop accurate approaches to measure, estimate and possibly forecast energy production with the goal of enabling early detection and diagnosis of parametric faults before they become catastrophic and lead to partial or full shut down of the plant. Moreover the ability of accurately predicting the energy output of a photovoltaic plant is becoming increasingly important to operate efficiently the existing power grid infrastructure that has difficulties with intermittent, unpredictable power sources. In this paper a new model of photovoltaic solar parks designed to estimate efficiency, predict energy production and enable early fault detection is presented. The proposed model is based on an equivalent electro-thermal model of the PhotoVoltaic (PV) cell, which takes as input the irradiance, ambient temperature and wind speed measured by existing sensors and data-logging equipment used in most solar PV parks. The proposed model is demonstrated to accurately predict the performance of real-life MW scale plants. By directly comparing predicted vs. actual energy production, it also allows easy and early identification and diagnose of malfunctions and efficiency drops of PV systems.

Technological processes represent the main source of protein and lipid oxidation in food. The oxidative status was determined in a soft Italian cheese, namely mozzarella, produced from water buffalo or bovine milk. The amount of protein-bound carbonyls, dityrosine and alpha-lactalbumin aggregates were measured to evaluate the extent of protein oxidation. The alpha-tocopherylquinone/alpha-tocopherol ratio and the trolox-equivalent antioxidant capacity were used as redox markers in the fat fraction. The levels of protein-bound carbonyls and alpha-lactalbumin aggregates were found significantly higher in mozzarella from bovine than in that from buffalo. On the contrary, higher amounts of redox markers were found in buffalo mozzarella. The levels of dityrosine aggregates were similar in the two groups of cheese. The data suggest that protein and fat are more protected against structure oxidative alterations in buffalo mozzarella than in bovine mozzarella

This paper proposes a novel electrical power system architecture capable to efficiently transfer energy from a solar generator to high power electric thrusters of a spacecraft. The architecture is based on a maximum power point tracker that acts on a DC/DC converter connected between a subsection of the solar generator and the thrusters. The other sections of the solar generator, that deliver most of the total power, are directly connected to the thrusters. The novelty of the proposed architecture is that the maximum power point tracker is always operating and, while conditioning only a fraction of the total power, is able to transfer to the thrusters an amount of power greater than the handled one.

The aim of this paper is to compare different architectures for a power system that supplies electrical thrusters for future space exploration missions. The main goal of these architectures is the maximization of the power extracted from the solar arrays in all operational situations and this is possible only by using peak power tracking algorithms. This limits the choice of architectures only to those including some form of peak power tracking algorithms. (5 pages)

A micro-inverter that takes as input the DC power generated by a solar panel (about 250W) and delivers it directly as AC power to the mains line is presented. The micro-inverter has been designed with discrete components, as it is common practice, since there are no silicon technologies that can be used to integrate the complete circuit and the passive components. The proposed micro-inverter has been extensively simulated and is currently under realisation. The obtained conversion efficiency is greater than 95% and the total harmonic distortion at the output is less than 0.4%.

In this paper we present a design for reliability methodology, with the goal of reducing the impact of transistor V TH degradation due for example to phenomena such as NBTI. It uses infrastructure IPs (I-IPs) featuring a self compensation scheme that automatically detects transistor aging effects and illustrates the design for test infrastructure used to make the SoC/System aware of the NBTI effects. This scheme is conceptually validated by using multi-level simulation and models. The discussion of possible exploitation models completes the paper.

The problem of mapping neural nets onto massively parallel architectures is considered. The solution examined, based upon regular array structures, can support the mapping of any neural graph. In particular, the case of feed-forward multilayered nets is analyzed, and is proven that in this case the mapping suggested is easily implemented and optimizes a number of relevant figures of merit. The structure of nodes, I/O ports, and switches is taken into account with reference to the neural net case. It is seen that the claims of inherent fault tolerance for neural nets are not actually kept for all classes of faults of a digital implementation; moreover, it is considered that end-of-production defects require restructuring to grant nominal initial operation. An efficient and straightforward solution to the defect-tolerance problem is presented, allowing the most limited redundancy versus good harvesting characteristics. >

This paper describes an application of neural networks as non-linear observers. The synthesis of such a network has been conducted on the basis of original criteria for the determination of the number of neurones and for the particular pattern selection method tailored onto the characteristics of the experiment. Possible extensions of such approaches are then considered.

Two different approaches to nonlinearity simplification in neural nets are presented. Both the solutions are based on approximation of the sigmoidal mapper often used in neural networks (extensions are being considered to allow approximation of a more general class of functions). In particular, a first solution yielding a very simple architecture, but involving discontinuous functions is presented; a second solution, slightly more complex, but based on a continuous function is then presented. This second solution has been successfully used in conjunction with the classical generalized delta rule algorithm. >

A novel digital architecture supporting implementation of feedforward, multilayered artificial neural networks is presented. Based on a switched bus array philosophy, particular care is taken to minimize area requirements while maximizing throughput and parallelism. The architecture is well suited to support, with minimal additional changes, fault/defect tolerance with respect to faults located in the PEs (processing elements), switches, or buses. >

The problem of speech recognition may be viewed as the identification of the basic components (phonemes) of the human speech through a high-level measurement procedure working on segments of the vocal signal, their classification, and the identification of their combination into the individual words so as to derive the complete word identification. The efficient and effective solution of the whole problem has several applications (e.g., the automatic typewriter) as well as the simple phoneme recognition may be exploited for some innovative areas (e.g., the voice compression for telecommunication). This paper shows the use of hybrid soft-computing techniques for the signal segmentation and the phoneme classification and the application to voice compression.

The performance of a process can be monitored by comparing the experimental results to the predictions from a mechanistic model or by using multivariate statistical projection methods such as principal component analysis (PCA) and projection to latent structures (PLS). Both approaches have advantages and drawbacks. In order to overcome such drawbacks, in this work an attempt to merge mechanistic and statistical models has been made.

A comparative benchmark of the linearity properties of two of the most popular compact transistor models (BSIM4 and PSP) for nanometre process technologies (45 nm) is presented. The determination of the IP3 compression point for a particular network configuration, which is often encountered in RF mixers, is used as a comparison vehicle. Parameters of both the PSP and BSIM4 models adopted in the comparison have been fitted to a leading-edge 45 nm RF technology. The benchmarks show that the BSIM4 model is unable to capture the IP3 compression point whereas the PSP model yields the expected behaviour, thus enabling the determination of the correct value of IIP3.

In this paper we present an architecture for implementation of artificial layered neural networks. The building blocks of the architecture are simple processing elements properly interconnected to a number of shift registers which provide the processing elements with data and weights. The paper concentrates on optimization of the architecture with respect to the three main parameters of silicon area requirements, computational latency and throughput.

Presents a solution that allows flexible mapping of neural nets (such as multi-layered ones) onto uncommitted processing arrays in which a large number of processing elements are interconnected by a switched-bus network. The basic algorithms leading to such mapping are outlined, providing a balance between structure simplicity and parallelism of operation speed. A protocol by which the array can be configured (and, therefore, initialized) is presented: nominal operation is then described, and it is seen that the same solution providing for initialization supports also subsequent algorithms. The structure of the basic elements of the architecture (switches and processing elements) is detailed, so as to allow an evaluation of complexity as regards silicon requirements in CMOS. >

Multiplications upon complex numbers are often required in applications such as signal processing: these application areas usually involve also relevant reliability requirements. In the present paper, two multipliers for complex numbers are presented, both characterized by reduced redundancy: the first solution provides not only self-testing, but also survival to a single fault through reconfiguration, while the second solution basically provides self-testing (reconfiguration can be achieved, but it requires some added difficulty). Redundancy is evaluated parametrically; error latency is plotted for various instances of input data lengths.

Cadmium stannate (Cd/sub 2/SnO/sub 4/) films of 1..cap omega.. per square sheet resistance and 85 percent average transmissivity (500 to 650 nm) were grown by means of rf sputtering onto silica substrates. CdS-Cu/sub 2/S thin film solar cells with conversion efficiencies greater than 5 percent for front and rear illumination were fabricated. The reflection of transmitted light back through the cell increased the light generated current. Fabrication techniques are described and current-voltage and spectral response measurements are presented for frontwall and backwall modes of operation. (7 figures)

A problem in expert systems is typically represented by an AND/OR graph. A set of spatial light modulators which can perform AND and OR logic operations can directly be applied to form an optical inference engine. The threshold-dependence logic operations of relatively low contrast and small dynamic range liquid crystal television are explained. The parallel inference architecture operated by liquid crystal televisions is presented.

The effect of grain size on short circuit current density was investigated by approximating individual silicon grains as right circular cylinders and solving the diffusion equation within the base region. This model confirms the previous results that for grain radii exceeding a few tenths of a millimeter, the minority carrier lifetime in the grain essentially determines the short-circuit current response of the cell. The dark I-V characteristics of some polycrystalline solar cells were measured and compared with single crystal cells. The dark current of the polycrystalline cells is dominated by recombination within the space-charge region well past the one sun maximum power point. This has the effect of lowering the cells output power and open circuit voltage. Single crystal cells are dominated by recombination within the quasi-neutral regions at the one sun maximum power point and, consequently, the fill factor and open circuit voltage are greater. Additionally, some preliminary measurements of the spatial dependence of diffusion length were made, Laue X-ray diffraction study of crystal orientations was performed and some SEM micrographs of polycrystalline wafers were taken.

The vertical junction effect in polysilicon solar cells (due to dopant penetration along grain boundaries) is investigated using a cylindrical grain model. The model shows that for small grain radii the short circuit current can increase above the single crystal value if the grain boundaries collect carriers and that th short-circuit current approaches the single crystal value as the grain size increases. The spatial dependence of the dark I-V characteristic is investigated by fabricating small diodes on a polysilicon wafer. Dark I-V characteristics are measured and illuminated characteristics are projected for each of the diodes. The diode characteristics are given together with SEM micrographs of the diodes and the effect of areal inhomogemety is investigated. The relative orientations of adjacent crystal grains and the nature of the boundaries between grains are studied by x-ray diffraction, optical microscopy and SEM methods. Orientation data is presented along with electron channelling patterns obtained from individual grains. A conclusion is drawn on the origin of sinuous grain boundaries.

A more detailed model of the vertical junction effect was generated which investigates both the increase in light generated current due to enhanced collection at the grain boundary and the increase in dark current due to the increased junction area. Results show that there is an overall increase in the cell's maximum power; however, the increase in power is negligible for grain widths exceeding a few tenths of a millimeter. Solar cells were fabricated on a longitudinal section of cast polysilicon which was analyzed crystallographically by means of x-ray diffraction patterns. Special crystallographic orientation relationships are identified for the relative orientations of adjacent grains and for the alignment of their boundary interfaces along certain planar segments. The dark I-V characteristics of the polysilicon cells were dominated by recombination within the space-charge region. Scanning photoresponse patterns are matched with the microstructural information to show, in the absence of any detectable impurity effects, that an insignificant or reduced photoresponse measurement is associated with certain boundaries depending on their structural character. The special orientations of grains are indicated on the basis of a model example to be derived from single or multiple twinning relationships on (111) systems.

The purpose of this program is to demonstrate the use of a concentrating photovoltaic system to provide the energy for operating a silicon solar cell production facility, i.e., to demonstrate a solar breeder. Solarex has proposed to conduct the first real test of the solar breeder concept by building and operating a 200 kW(e) (peak) concentrating photovoltaic system based on the prototype and system design developed during Phase I. This system will provide all of the electrical and thermal energy required to operate a solar cell production line. This demonstration would be conducted at the Solarex Rockville facility, with the photovoltaic array located over the company parking lot and on an otherwise unusable flood plain. Phase I of this program included a comprehensive analysis of the application, prototype fabrication and evaluation, system design and specification, and a detailed plan for Phases II and III. A number of prototype tracking concentrator solar collectors were constructed and operated. Extensive system analysis was performed to design the Phase II system as a stand-alone power supply for a solar cell production line. Finally, a detailed system fabrication proposal for Phase II and an operation and evaluation plan for Phase III were completed. These proposalsmore » included technical, management, and cost plans for the fabrication and exercise of the proposed system.« less