Economic design of (X)over-bar and R charts under Weibull shock models

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Design and management optimization of trickle irrigation systems using non-linear programming

A non-linear model is presented which optimizes the lay-out, as well as the design and management of trickle irrigation systems, to achieve maximum net benefit. The model consists of an objective function that maximizes profit at the farm level, subject to appropriate geometric and hydraulic constraints. It can be applied to rectangular shaped fields, with uniform or zero slope. The software used is the Gams-Minos package. The basic inputs are the crop-water-production function, the cost function and cost of system components, and design variables. The main outputs are the annual net benefit and pipe diameters and lengths. To illustrate the capability of the model, a sensitivity analysis of the annual net benefit for a citrus field is evaluated with respect to irrigated area, ground slope, micro-sprinkler discharge and shape of the field. The sensitivity analysis suggests that the greatest benefit is obtained with the smallest microsprinkler discharge, the greatest area, a square field and zero ground slope. The costs of the investment and energy are the components of the objective function that had the greatest effect in the 120 situations evaluated. (C) 1996 Academic Press Limited

A single intraoperative sub-Tenon's capsule triamcinolone acetonide injection for the treatment of post-cataract surgery inflammation

Purpose: To compare a single intraoperative sub-Tenon's capsule triamcinolone acetonicle injection with steroid drops in the treatment of ocular inflammation after cataract surgery.Design: Randomized, double-masked controlled trial.Participants: A total of 100 patients were randomized prospectively into 2 groups: 50 patients treated with 1% prednisolone eyedrops (control group A) and 50 patients treated with sub-Tenon's capsule triamcinolone (treatment group B).Methods: All patients underwent phacoemulsification and intraocular posterior lens implantation. After surgery, patients were randomized to receive either (group B) an intraoperative 40 mg triamcinolone acetonicle sub-Tenon's capsule injection or (group A) 1% prednisolone acetate eyedrops, according to the following schedule: 1 drop 4 times daily (week 1), 3 times daily (week 2), 2 times daily (week 3), once daily (week 4). To mask the study, group B received vehicle drops administered on a similar schedule, and group A received an intraoperative sub-Tenon's capsule injection of a 1 ml balanced salt solution.Main Outcome Measures: the main outcome measures included inflammation (cell, flare, ciliary flush), intraocular pressure, and lack of response.Results: Triamcinolone was shown to have anti-inflammatory efficacy clinically equivalent to conventional 1% prednisolone eyedrops in reducing intraocular inflammation, as measured by clinical methods. Triamcinolone was found to be as safe as the prednisolone in terms of adverse effects, changes in visual acuity, intraocular pressure, and biomicroscopic and ophthalmoscopic variables. on the third, seventh, fourteenth, and twenty-eighth postoperative days, a significantly lower intraocular pressure (P<0.01) was noted in the triamcinolone group than in the prednisolone group.Conclusions: A single intraoperative 40-mg triamcinolone acetonide sub-Tenon's capsule injection demonstrated a clinically equivalent therapeutic response and ocular tolerance compared with 1% prednisolone drops in controlling postoperative inflammation after uncomplicated cataract surgery and merits further investigation. (C) 2004 by the American Academy of Ophthalmology.

Epstein-barr virus infection and single nucleotide Polymorphisms in the promoter region of interleukin 10 gene in patients with Hodgkin lymphoma

Context. - Hodgkin lymphoma is a neoplastic disease in which the immune system plays a major role in its pathogenesis. Interleukin 10 ( IL-10), an immunosuppressive cytokine actively produced in patients with Hodgkin lymphomas, favors the survival of the Hodgkin/Reed-Sternberg cells. Individual variations in IL-10 levels may be due, in part, to the presence of single nucleotide polymorphisms in the IL10 gene promoter.Objective. - To evaluate whether particular single nucleotide polymorphisms in the IL10 gene are found more frequently in Hodgkin lymphoma cases associated with Epstein-Barr virus infection.Design. - the identification of single nucleotide polymorphisms at positions -1082 and -819/-592 in the IL10 gene was performed by polymerase chain reaction and restriction length fragment polymorphisms analysis in 65 cases of Hodgkin lymphoma and 50 cases of reactive benign follicular lymphoid hyperplasia ( non-Hodgkin lymphoma control group).Results. - the frequency of the genotype GG at position -1082 was found to be significantly higher in patients with Epstein-Barr virus-positive Hodgkin lymphoma compared with Epstein-Barr virus-negative cases.Conclusions. - the results suggest that the presence of specific single nucleotide polymorphisms in the IL10 gene, notably those associated with high IL-10 production, may play a role in the susceptibility to Epstein-Barr virus -positive Hodgkin lymphoma development.

Joint conomic design of (x)over-bar and R charts under Weibull shock models

This paper deals with the joint economic design of (x) over bar and R charts when the occurrence times of assignable causes follow Weibull distributions with increasing failure rates. The variable quality characteristic is assumed to be normally distributed and the process is subject to two independent assignable causes (such as tool wear-out, overheating, or vibration). One cause changes the process mean and the other changes the process variance. However, the occurrence of one kind of assignable cause does not preclude the occurrence of the other. A cost model is developed and a non-uniform sampling interval scheme is adopted. A two-step search procedure is employed to determine the optimum design parameters. Finally, a sensitivity analysis of the model is conducted, and the cost savings associated with the use of non-uniform sampling intervals instead of constant sampling intervals are evaluated.

Design of a LNA and a Gilbert Cell Mixer MMICs with a GaAsPHEMT technology

The design of a Gilbert Cell Mixer and a low noise amplifier (LNA), using GaAs PHEMT technology is presented. The compatibility is shown for co-integration of both block on the same chip, to form a high performance 1.9 GHz receiver front end. The designed LNA shows 9.23 dB gain and 2.01 dB noise figure (NF). The mixer is designed to operate at RF=1.9 GHz, LO=2.0 GHz and IF=100 MHz with a gain of 14.3 dB and single sideband noise figure (SSB NF) of 9.6 dB. The mixer presents a bandwith of 8 GHz.

Identification and analysis of single nucleotide polymorphisms (SNPs) in citrus

Most of the cultivated species of citrus have narrow genetic basis. Relationships among species and cultivars are obscured by sexual compatibility, polyembryony, apomixis and a high incidence of somatic mutations. DNA analysis is crucial in genetic studies not only for citrus breeding programs but also for characterization of hybrids and species. In this paper, single nucleotide polymorphisms ( SNPs) were investigated in 58 accessions of Citrus, hybrids and related genera. Genomic sequences of 'Pera IAC' sweet orange ( Citrus sinensis L. Osbeck) were used for primer design and selection of sequence tagged sites (STSs) for identification of SNPs. Analysis of 36 STSs showed identical sequences among 40 of the 41 sweet orange accessions studied. However, these accessions were heterozygous for many SNPs. Ten selected STSs were analyzed in 17 additional accessions from 13 species and hybrids. Comparing to the 'Pera IAC' sweet orange accession, a total of 150 polymorphic nucleotides were identified and most of the alterations were transitions ( 52.7%). The greatest number of SNPs was observed in Poncirus trifoliata ( L.) Raf. and the smallest in 'Ponkan' mandarin ( Citrus reticulata Blanco). At the intra-specific level, 'Bafa Gigante' ( Citrus sinensis L. Osbeck) was the only sweet orange accession with a divergent SNPs genotype, which corroborates the hypothesis of a hybrid origin for this accession. Although the STSs analyzed represent randomly sampled genomic sequences, they provided consistent information about the level of polymorphism and showed the potential of SNPs markers for characterization and phylogenetic studies.

A CMOS/SOI single-input PWM discriminator for low-voltage body-implanted applications

A CMOS/SOI circuit to decode Pulse-Width Modulation (PWM) signals is presented as part of a body-implanted neurostimulator for visual prosthesis. Since encoded data is the sole input to the circuit, the decoding technique is based on a novel double-integration concept and does not require low-pass filtering. Non-overlapping control phases are internally derived from the incoming pulses and a fast-settling comparator ensures good discrimination accuracy in the megahertz range. The circuit was integrated on a 2 mum single-metal thin-film CMOS/SOI fabrication process and has an effective area of 2 mm(2). Measured resolution of encoding parameter a is better than 10% at 6 MHz and V-DD = 3.3 V. Idle-mode consumption is 340 LW. Pulses of frequencies up to 15 MHz and alpha = 10% can be discriminated for 2.3 V less than or equal to V-DD less than or equal to 3.3 V. Such an excellent immunity to V-DD deviations meets a design specification with respect to inherent coupling losses on transmitting data and power by means of a transcutaneous link.

Adaptive control charts: A Markovian approach for processes subject to independent disturbances

Recent studies have shown that adaptive X control charts are quicker than traditional X charts in detecting small to moderate shifts in a process. In this article, we propose a joint statistical design of adaptive X and R charts having all design parameters varying adaptively. The process is subjected to two independent assignable causes. One cause changes the process mean and the other changes the process variance. However, the occurrence of one kind of assignable cause does not preclude the occurrence of the other. It is assumed that the quality characteristic is normally distributed and the time that the process remains in control has exponential distribution. Performance measures of these adaptive control charts are obtained through a Markov chain approach. (c) 2005 Elsevier B.V. All rights reserved.

Harmonic identification using parallel neural networks in single-phase systems

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Design, construction, and performance of a real-time holographic refractometry prototype for liquid analysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A unity power factor multiple isolated outputs switching mode power supply using a single switch

The authors present an offline switching power supply with multiple isolated outputs and unity power factor with the use of only one power processing stage, based on the DC-DC SEPIC (single ended primary inductance converter) modulated by variable hysteresis current control. The principle of operation, the theoretical analysis, the design procedure, an example, and simulation results are presented. A laboratory prototype, rated at 160 W, operating at a maximum switching frequency of 100 kHz, with isolated outputs rated at +5 V/15 A -5 V/1 A, +12 V/6 A and -12 V/1 A, has been built given an input power factor near unity.

Intestinal colonization of a human subject by vancomycin-resistant Enterococcus faecium

Objective: To study the ability of two strains of vancomycin-resistant Enterococcus faecium to colonize the human intestine. Methods: A single human subject ingested separately two strains of vancomycin-resistant E. faecium isolated from a pig and a chicken. The feces were cultured on selective medium. Prior to ingestion no vancomycin-resistant cocci were present in the feces. Ingestion of 10 4-10 5 CFU resulted in either no colonization or isolation only after enrichment. Ingestion of 10 7 CFU of one strain resulted in colonization for a period of nearly 3 weeks, with fecal counts at times in excess of 10 6 CFU/g. Ingestion of similar numbers of the other strain and reingestion of the first strain resulted in excretion in the feces for much shorter periods. When the fecal count of the ingested strains was greater than 10 4-10 5 CFU/g, the strains were isolated from swabs taken from perianal skin. Conclusions: Vancomycin-resistant E. faecium strains from pigs and poultry a re able to colonize the human gut and the perianal skin.

Design of a LNA and a Gilbert Cell Mixer MMICs with a GaAs PHEMT technology

The design of a Gilbert Cell Mixer and a low noise amplifier (LNA), using GaAs PHEMT technology is presented. The compatibility is shown for co-integration of both block on the same chip, to form a high performance 1.9 GHz receiver front-end. The designed LNA shows 9.23 dB gain and 2.01 dB noise figure (NF). The mixer is designed to operate at RF=1.9 GHz, LO=2.0 GHz and IF=100 MHz with a gain of 14.3 dB and single sideband noise figure (SSB NF) of 9.6 dB. The mixer presents a bandwith of 8 GHz.

Joint conomic design of x̄ and R charts under Weibull shock models

This paper deals with the joint economic design of x̄ and R charts when the occurrence times of assignable causes follow Weibull distributions with increasing failure rates. The variable quality characteristic is assumed to be normally distributed and the process is subject to two independent assignable causes (such as tool wear-out, overheating, or vibration). One cause changes the process mean and the other changes the process variance. However, the occurrence of one kind of assignable cause does not preclude the occurrence of the other. A cost model is developed and a non-uniform sampling interval scheme is adopted. A two-step search procedure is employed to determine the optimum design parameters. Finally, a sensitivity analysis of the model is conducted, and the cost savings associated with the use of non-uniform sampling intervals instead of constant sampling intervals are evaluated.