Optimization models for computer data storage design: An application

In this paper we discuss a model being used to optimize the system design of the Computer Centre of one of the most important Italian banking groups. Data and transactions, processed by the system, are grouped respectively in data sets and by type, so it is possible to deal with the large dimensions of the corresponding optimization models. The transactions' arrivals are considered as stochastic variables and their probability values are estimated on the base of theoretical considerations. The solutions for two optimization problems, constructed and solved for different scenarios, are discussed in detail.     

Channel coding for asynchronous fiberoptic CDMA communications

Several studies have explored the feasibility and systems performance aspects of a code division multiple access (CDMA) format for fiberoptic networks. Previously discussed CDMA architectures would either have to tolerate a high bit error rate or be forced to use long code sequences in networks with even a moderate number of simultaneous users. The use of long sequences lowers the maximum achievable bit rate or places unrealistic requirements on the system hardware. This paper examines some of the possible improvements to system performance that could be realized by combining the CDMA format with external error correcting codes (ECCs) or a PPM format. It is determined that ECCs can be highly effective in lowering the BER, and/or increasing the achievable information bit rate and number of network users. The results are sufficiently encouraging to conclude that one should seriously consider including ECCs in any practical fiberoptic CDMA network     

Some considerations on the iterative harmonic analysis convergence

The convergence difficulties of the iterative harmonic analysis (IHA) methodologies are considered. Two techniques proposed to improve IHA convergence are described and their applicability limits are analyzed. To overcome the aforementioned limits, a third improvement technique is presented. A critical case study is solved by means of IHA and the three improvement techniques, and the results are analyzed and discussed     

Bezafibrate-induced myopathy: no evidence for defects in muscle metabolism

The authors report 8 cases of coverage of the inguinal and perineal areas with the inferiorly based rectus abdominis myocutaneous flap. This flap seems to be the technique of choice for coverage of such defects. The design of the flap can be explained by the low venous pressure zone concept.     

Seeing and knowing: Knowledge attribution versus stimulus control in adult humans (Homo sapiens).

Interest in cognition in nonhuman animals has inspired new approaches to discovering animals' ability to attribute knowledge to others (e.g., D. J. Povinelli, K. E. Nelson, & S. T. Boysen; see record 1991-00392-001). The assumptions of such experiments were tested in this study by training a group of humans (Homo sapiens) to use accurate information provided by a confederate who was watching as 1 container among 4 was baited; a 2nd group was similarly trained to use accurate information provided by a confederate whose back was turned during baiting. On a single reversal trial, the roles of the 2 confederates were switched. Subjects were able to learn their respective tasks but attended to different aspects of the confederates, as revealed by the reversal trial. Although attributional interpretations can be applied to such data, many of the choices in this experiment can be explained more readily with the basic principles of contingency-based learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender bias in subject samples in counseling psychology.

In the past decades, there has been a disproportionate emphasis on the use of male subjects in psychological research (e.g., Carlson & Carlson, 1960; Schwabacher, 1972). In this study, we examined how the use and reporting of the gender of subjects in counseling psychology research has changed during the decade from 1971-1972 to 1981-1982. For this time period, articles from two journals, the Journal of Counseling Psychology (JCP) and the Journal of Vocational Behavior (JVB), were examined for specification of sex of subjects, analysis for sex differences, and appropriate generalization of single-sex studies. Results indicate that (a) reporting of gender as a subject variable increased from 1971-1972 to 1981-1982; (b) in 58% of the studies, results were analyzed for gender differences; (c) JVB was more likely than JCP to publish articles in which gender differences were analyzed; and (d) in over 60% of the studies in 1971-1972 and 26% of the studies in 1981-1982, findings regarding subject gender seemed to be overgeneralized. The results are discussed in terms of the need to develop gender-specific data bases, journal policies, and future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Polymeric PEGylated nanoparticles as drug carriers: How preparation and loading procedures influence functional properties

The application of emerging nanotechnologies in medicine showed in the last years a significant potential in the improvement of therapies. In particular, polymeric nanocarriers are currently tested to evaluate their capability to reduce side effects, to increase the residence time in the body and also to obtain a controlled release over time. In the present work a novel polymeric nanocarrier was developed and optimized to obtain, with the same chemical formulation, three different typologies of nanocarriers: dense nanospheres loaded with an active molecule (1) during nanoparticle formation and (2) after the preparation and (3) hollow nanocapsules to increase the starting drug payload. Synthetic materials considered were PEGylated acrylic copolymers, folic acid was used as model of a hydrophobic drug. The main aim is to develop an optimized nanocarrier for the transport and the enhanced release of poorly water‐soluble drugs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41310.     

Optoelectronic simulation and thickness optimization of energetically disordered organic solar cells

In this work a complete semi-classical model of an organic solar cell is presented. The different aspects of conversion of light to electricity are taken into account. Correct models for density of state and organic-metal interface are considered in order to include the effect of energetically disorder material properties. Most of the parameters for the model are taken from literature while some were fixed by fitting with several experimental current-voltage characteristics. The comparison between modeling results and experimental data shows consistency and are in good agreement. Finally the model is used to investigate the optimization of hole transport (PEDOT) and active (P3HT:PCBM) layer thicknesses in order to maximize the cell efficiency. The simulation of the efficiency of the cell with varying thickness shows a fine tuning between the exciton generation and the charge recombination, giving clear indications on the optimization of cell performance.     

Molecular distillation of copaiba oleoresin—A clean process for diterpenes enrichment

Copaiba oleoresin has sesquiterpenes and diterpenes with significant medicinal properties, including being antimicrobial, antiparasitic, and wound healing, among others. Thus, the objective of this work was to study the diterpene enrichment of the copaiba oleoresin from Copaifera officinalis via molecular distillation. Evaporator temperature (EVT) and feed flow rate (Q) were evaluated using an experimental design (2² with central point) considering the ratio of distillate and residue streams (DTR) as the response to optimize the residue recovery. EVT and Q were the main effects for diterpenes recovery, with the best experimental condition at 100°C (EVT) and 15 ml/min (Q) under 0.001 mbar, of which the residue stream had a diterpenes content of 99.25%. With the molecular distillation process, it was possible to add value to the copaiba streams, separating and purifying diterpenes with applicability in the biomedical and pharmaceutical industries since no solvent is used in this process (clean).