Retention Power Research Articles

Replica Technique for Adaptive Refresh Timing of Gain-Cell-Embedded DRAM

Gain cells have recently been shown to be a viable alternative to static random access memory in low-power applications due to their low leakage currents and high density. The primary component of power consumption in these arrays is the dynamic power consumed during periodic refresh operations. Refresh timing is traditionally set according to a worst-case evaluation of retention time under extreme process variations, and worst-case access statistics, leading to frequent power-hungry refresh cycles. In this brief we present a replica technique for automatically tracking the retention time of a gain-cell-embedded dynamic-random-access-memory macrocell according to process variations and operating statistics, thereby reducing the data retention power of the array. A 2-kb array was designed and fabricated in a mature 0.18-μm CMOS process, appropriate for integration in ultralow power applications, such as biomedical sensors. Measurements show efficient retention time tracking across a range of supply voltages and access statistics, lowering the refresh frequency by more than 5×, as compared with traditional worst-case design.

Selective State Retention Power Gating Based on Gate-Level Analysis

This work presents a novel approach based on gate-level analysis for implementing Selective State Retention Power Gating (SSRPG). A selective SRPG approach mitigates the area and power overhead of the conventional SRPG technique. However, only very few papers suggesting a selective SPRG approach were published. The proposed SSRPG technique employs a formal analysis and, therefore, does not require exhaustive simulations. To implement the new approach, an automatic algorithm, which is performed on a gate-level netlist, has been developed. This algorithm enables the extraction of a subset of flip-flops that is sufficient for a proper state retention power gating. Unique selective SRPG criteria have been defined to support the proposed algorithm. These criteria are used to reduce the total amount of the required retention cells. To the best of our knowledge, this is the first robust SSRPG approach using gate-level analysis for selecting a reduced sub set of FFs that require retention. The proposed approach has been applied to a practical design with about 3300 FFs. The experimental results show 78% reduction of the retention SPRG cell area overhead, compared to the common SRPG approach.

THE EFFECTS OF AUTHENTIC PEDAGOGICAL PRACTICES ON STUDENTS’ EDUCATIONAL PERFORMANCES AND RETENTION POWER

In-practice traditional lecture, discussion and assignments based pedagogical practices play its role in students’ learning and retention power. The current study intends to investigate whether authentic pedagogical practices are more effective in terms of enhancing students’ educational performances and retention power or the traditional pedagogical practices. Therefore, this study focused on investigating the effects of authentic and traditional pedagogical practices on students’ educational performances and retention power at secondary level. The objective was to measure the effects of authentic and traditional pedagogical practices on students’ educational performances and retention power. A pre-test post-test comparative group design was adopted to conduct the study. The students of experimental group were exposed to authentic pedagogical practices while the control group was treated on traditional routine pedagogical practices. Data from the experimental and control group were collected through a self-developed test. Thrice was the test administered to both groups, the collected data were analyzed through Mean, Standard Deviation and independent sample t-test. Results of the study concludes that students of experimental group performed higher on the post-test than the students of control group, the performance of experimental group was also better as compared to the control group on the test of retention power. Keeping in view the results that data yielded, it was recommended that teachers at secondary level may follow authentic pedagogical practices as compared to other traditional ones. Based on the findings of the study relevant and applicable recommendations were made.

In Defense of a Hybrid Model for EFL Vocabulary Instruction

Vocabulary instruction has been tackled from various perspectives mainly in the form of taking the advan-tages of Vocabulary Learning Strategies (VLSs), but few validation and verification efforts are traceable in the literature. To fill the gap, this study was an attempt to validate, and then verify the feasibility of a hybrid model against lexical inferencing strategy on the retention rate of Iranian EFL learners. Sixty homogeneous students from different intact classes participated in these studies, who were exposed to treatments. Having received a diagnostic vocabulary pre-test, one group was exposed to infertencing-based strategy, while another received instruction in the form of multiple visualizations called characterized a Hybrid Model. In addition to the statistical analyses on test validation procedures, Leven’s test verified the similar variances between two experimental groups prior to then treatments. However, the results of post-test pointed out that, though both groups had significant progress, the Hybrid Model group outperformed the lexical inferencing group not only in achievement but in retention power of the vocabulary items.

De invloed van nieuwe en hardnekkige loopbaanpraktijken op de duurzaamheid van loopbanen

The impact of new and persistent career practices on sustainable employability The impact of new and persistent career practices on sustainable employability This article addresses two central research questions: Which career levers stimulate work engagement and do these also have retention power? A broad conceptual spectrum is used covering typical labor psychological and sociological concepts (protean career attitude, obsolescence, labor ethics) and typical (sustainable) HR concepts (employability, career management, diversity). The research results indicate a positive relationship between age and engagement. Consequently, the opinion that older workers lack the necessary energy seems to be nothing more than a mere cliché. Based on these results, innovative concepts such as organizational career management – taking into account the needs of employees at any career stage – look to be promising. Persistent (career) practices as obsolescence and negative age stereotyping put a mortgage on engagement and retention. Therefore, we plea against such practices and we advocate a shift towards a career management which enables sustainable employability and engagement.

CHARACTERISATION OF HEAVY METALS IN LICHEN SPECIES HYPOGYMNIA PHYSODES AND EVERNIA PRUNASTRI DUE TO BIOMONITORING OF AIR POLLUTION IN THE VICINITY OF COPPER MINE

Lichen species (Hypogymnia physodes and Evernia prunastri) were used for biomonitoring the possible air pollution with heavy metals in the vicinity of copper mine in the eastern part of the Republic of Macedonia. The contents of 18 elements were analysed by ICP-AES and ETAAS techniques. For data processing basic statistical methods and multivariate exploratory (factor and cluster analysis) techniques were applied. Three geogenic and one anthropogenic group of elements were singled out from factor analysis. Maps of spatial distribution of elements from the anthropogenic group showed an increased content of the anthropogenic elements only in close vicinity to the mine. A maximum value obtained for Cu content was 130 mg/kg and for Pb content was 120 mg/kg. Lichen talus of the collected species showed high retention power for accumulation of the anthropogenic group of elements compared to moss species sampled from the same study area (r=0.86 and r=0.68). Here we show that lichens can be use as biomonitors for atmospheric distribution of anthropogenic- introduced elements.

A Gaming Model for Teaching Autistic Children Basic Traffic Rules

Autism is a disorder of neural development which affects about one in every 150 kids on average. Autism deals with major complexities regarding social communication and retention power. Now days, due to the increased use of the computer, the technology is being used to assist the treatment and to interact with an autistic child. To make the learning environment more attractive, the animated pictures are used in the applications. In this paper a gaming model is proposed which will first teach basic traffic rules to Autistic children with the help of some animated videos and then help them decide what action must be taken in certain situations thus increasing their intelligibility. The use of tangible objects is introduced so as to keep the sessions more interesting for autistic children.

PA01.33. Mode of action of medhya drugs: A review

Purpose: Memory is combination of power of acquisition (Grahan), retention (Dharan) and recollection (Smaran). Vata, pitta, and kapha are the three psychobiological dimensions (energy) or biological rhythms regulating the entire functioning of the human body. Pitta is responsible for understanding and attaining knowledge due to its Satva, Aashukari and Tikshna property. Vata is responsible for association of ideas. Kapha provides stability which is necessary for retention of memory. Several Central Nervous System disorders (CNS) are often associated with impairment in cognitive functions. Disorders of memory can range from mild to severe. It is major health problem of 21st century. Main objective of this work is to understand the ayurvedic aspect of learning and memory mode of action of some medhya drugs W.S.R. Vacha, Shankhpushpi, Endri, Jyotishmati and brahmi. Method: A review on available scientific information in terms of references in classical texts, and Nighantus, chemical constitute, pharmacological activity is prepared with a view to understand mode of action of these Medhya dravya. Result: Pitta is responsible for understanding and attaining knowledge due to its Satva, Aashukari and Tikshna property. Vata is responsible for association of ideas. Kapha provides stability which is necessary for retention of memory. Sheetvirya and improves retention power and ushna virya drugs enhance power of acquiring new information and data interpretation. Conclusion: Ushna virya and sheet virya drugs acts through different mechanism and enhance cognition. It may provide parameters for selection of medhya drug in different memory disorder.

Reliable State Retention-Based Embedded Processors Through Monitoring and Recovery

State retention power gating and voltage-scaled state retention are two effective design techniques, commonly employed in embedded processors, for reducing idle circuit leakage power. This paper presents a methodology for improving the reliability of embedded processors in the presence of power supply noise and soft errors. A key feature of the method is low cost, which is achieved through reuse of the scan chain for state monitoring, and it is effective because it can correct single and multiple bit errors through hardware and software, respectively. To validate the methodology, ARM® Cortex™-M0 embedded microprocessor (provided by our industrial project partner) is implemented in field-programmable gate array and further synthesized using 65-nm technology to quantify the cost in terms of area, latency, and energy. It is shown that the proposed methodology has a small area overhead (8.6%) with less than 4% worst-case increase in critical path and is capable of detecting and correcting both single bit and multibit errors for a wide range of fault rates.

Thermoreversible Gelation of Poly(vinylidene fluoride-co-chlorotrifluoroethylene): Structure, Morphology, Thermodynamics, and Theoretical Prediction

Thermoreversible gelation of a copolymer, poly(vinylidene fluoride-co-chlorotrifluoroethylene), has been studied in a series of aromatic diesters (phthalates) with varying aliphatic chain length, n. The gelation rate gradually increases with increasing n, but no gelation occurs in dioctyl phthalate (n = 8), giving rise to a solvent dependency. Structures of gels and dried gels have been studied through X-ray diffraction and FTIR studies. Fibrillar morphology is evident for the series of solvents, but its dimension (both lateral and diameter) systematically changes with n. Solvent retention power of gels has gradually been increased with increasing n while the thermal degradation of copolymer occurs at same temperature, reflecting varying interactions between copolymer and various aliphatic chain length phthalates in gels. Phase diagrams of the gels exhibit the formation of two kinds of polymer−solvent complexes and have been predicted theoretically through electronic structure calculation. Both the small-...

Retention Behavior of Fluorobenzenes on Fluoro-Derivatized Poly(<i>p</i>-phenylene terephthalamide) Fibrous Stationary Phases in Microcolumn Liquid Chromatography

Surface derivatization of poly(p-phenylene terephthalamide) (PPTA) fibers was studied to prepare novel stationary phases in liquid chromatography (LC). As one type of surface derivatization of synthetic fibers, alkyl or perfluoroalkyl chains as functional groups were introduced to the surfaces of PPTA fibers. When each functionalized fiber-packed column was used for LC, increases in retention power with respect to a variety of compounds were ascertained in comparison with that prepared by an untreated-fiber as the stationary phase. Furthermore, it was indicated that the perfluoroalkyl group introduced fibrous stationary phase showed a specific retention behavior with respect to halogenated benzenes. These results demonstrated that the derivatization of the surfaces of PPTA fibers was successfully carried out. Selectivity differences between the modified-fiber packed columns were also confirmed through the use of some sample probes.

Solvent Retention, Thermodynamics, Rheology and Small Angle X-ray Scattering Studies on Thermoreversible Poly(vinylidene fluoride) Gels

Solvent retention power of poly(vinylidene fluoride) (PVDF) gels has been studied for various homologues of phthalate (aromatic diesters). The thermal stability has been examined for gels of varying morphology. Solvent evaporation, gelation, gel melting, and polymer degradation temperatures have increased with increasing aliphatic chain length of phthalates. The thermodynamics and polymer-solvent compound formations in the PVDF-phthalate gels have been explored. The weight fraction of polymer in compound has decreased with increasing aliphatic chain length. SAXS studies have confirmed the lamellar organization inside the fibrils, and interlamellar distance increases with aliphatic chain length of diesters. The scattering patterns follow the power law behavior (I(q) approximately q(-alpha)), and polymer gels consist of high-density mass (fibril), voids, and interlamellar region. Dynamic mechanical properties indicate the splintering and reformation of network structure in gels whose percolation frequency has reduced for higher aliphatic chain length phthalate. Morphology-dependent moduli have been observed, and greater mechanical strength has been verified for thicker fibrillar gels both for steady and dynamic measurements.

Effects of the Nonvolatile Matrix on the Aroma Perception of Wine

Eighteen reconstituted wine samples were prepared by mixing nonvolatile and volatile fractions obtained from six different wines, two whites and four reds, with different characteristics, in an approach that makes it possible to have the same aroma composition in different nonvolatile matrices and vice versa. The aroma elicited by those reconstituted samples was described by a specifically trained sensory panel. Additional gas chromatography-olfactometric and gas chromatography-mass spectrometric studies were carried out to measure differences in aroma release. Results have shown that the nonvolatile matrix of wine exerts a powerful effect on the perception of aroma, strong enough even to make a white wine aroma to smell as a red wine (increasing red, black, and dry fruit notes in detriment of white, yellow, citrus, and tropical) and vice versa and also to create differences in the aroma of reds. It has also been confirmed that the wine nonvolatile matrix exerts a powerful influence on the release of odorants. In particular, headspaces above a white wine matrix are richer in fruity esters and volatile fatty acids. Red wine nonvolatile matrices seem also to retain strongly 3-mercaptohexyl acetate, hence reducing its sensory impact. Comparison of red wine nonvolatile matrices reveals that differences in the retention power of the matrix can affect differentially the pattern of release of linear and branched esters and also of acids.

Thermally stimulated current spectra of binder resin powders for copiers: Correction for thermal shrinkage of the sample powder compactions

Thermally stimulated current (TSC) spectra observed under open- circuit condition for styrene- acrylic binder resin powder compactions for toners are corrected for their thermal shrinkage during TSC observation. For this binder resin, extrinsic current from motion of powder compactions with charges due to their thermal shrinkage was found to be much more effective than the sensitivity coefficient of a TSC measuring apparatus used. Particle size dependence of charge retention power of the resin powders was also examined by using this correction method and found that it decreased with decreasing their particle size.

The effects of hemicelluloses and lignin removal on water uptake behavior of hemp fibers

This study investigated the individual influences of hemicelluloses and lignin removal on the water uptake behavior of hemp fibers. Hemp fibers with different content of either hemicelluloses or lignin were obtained by chemical treatment with 17.5% sodium hydroxide or 0.7% sodium chlorite. Various tests (capillary rise method, moisture sorption, water retention power) were applied to evaluate the change in water uptake of modified hemp fibers. The obtained results show that when the content of either hemicelluloses or lignin is reduced progressively by chemical treatment, the capillary properties of hemp fibers are improved, i.e. capillary rise height of modified fibers is increased up to 2.7 times in relation to unmodified fibers. Furthermore, hemicelluloses removal increases the moisture sorption and decreases the water retention values of hemp fibers, while lignin removal decreases the moisture sorption and increases the water retention ability of hemp fibers.

Characteristics of Firms Responding to Underwater Employee Stock Options: Evidence from Traditional Repricings, 6&1 Exchanges, and Makeup Grants

ABSTRACT: I examine the characteristics of firms choosing to respond to underwater employee stock options using one of three stock-option-based responses. A traditional repricing offers a new and lower exercise price to restore the incentive alignment and retention power lost in underwater options, but is subject to potential expense recognition. A 6&1 exchange likewise restores what was lost in underwater options, but avoids potential expense recognition by delaying the issuance of replacement options until six months and one day later. A makeup grant potentially increases the total option value lost and avoids potential expense recognition, but is more dilutive since old underwater options are not cancelled. Results indicate that makeup grant firms have relatively deeper underwater options with shorter expected remaining lives. Makeup grant firms also issue these options to more non-executives compared to traditional repricing firms. I also find that while both makeup grant and 6&1 exchange firms have less insider ownership and historically report positive income more so than traditional repricing firms 6&1 exchange firms have greater overhang than makeup grant firms. Taken together, a possible explanation for these results is that firms that have more incentive alignment and/or retention power lost in underwater options prefer makeup grants that potentially increase total option value for its non-executive optionholders. However, when dilution from options is also a concern, it appears these firms may opt for a 6&1 exchange. In addition, it is possible that the choice of response is associated more with the desire to avoid recognizing option expense, rather than with potential rent extraction opportunities, as critics claim.

Evaluation of relationship between the <italic>Centella asiatica</italic> (Linn) fresh leaf extract induced spatial learning and memory enhancement and increased body weight gain in neonatal and adult rats

Centella asiatica (CeA) is a plant which grows in damp places in India and other Asian Countries. In Ayurvedic system of medicine, an alternative system of medicine practised mainly in India, leaves of CeA are used along with some other herbs as medhya drugs for memory enhancement and as promoter of strength and digestive power. In the present study, we have tried to establish the relation ship between the two of the properties of this plant. That is, spatial learning and memory enhancing property and its effect on overall body weight growth in neonatal and adult rats. The present study was conducted in neonatal (7day old) and adult (2.5 month old) rats. Both the groups of rats were fed with 2, 4 and 6ml/kg body of fresh leaf extract of CeA for 2, 4 and 6 weeks. During the treatment period the body weight of rats were noted at the end of every week. The body weight gained by the rats was compared with the spatial learning and memory enhancing effects of CeA on these rats reported earlier. The results showed a dose and duration dependent significance increase in the body weight gain in rats treated with CeA. This increase in the body weight was seen only in those groups were there was significant increase in spatial learning performance and enhanced memory retention power. This indicates that, there is a relationship between the spatial learning and memory enhancing effect of CeA and the body weight gain in rats.

Concentração de cátions presentes no lixiviado de solos tratados com vinhaça

O presente estudo teve como objetivo avaliar a qualidade do lixiviado de solos que receberam doses de vinhaça em diferentes tempos de incubação. Para isso, em 27 colunas de PVC de 20 x 110 cm (diâmetro x altura), foram reproduzidos três solos classificados como Nitossolo Háplico, Argissolo Amarelo e Espodossolo Cárbico, com horizontes, espessuras e densidades semelhantes à original. Os solos foram tratados com vinhaça em doses equivalentes a 0 (testemunha), 350 e 700 m³ ha-1 e submetidos aos tempos de incubação de 30 e 60 dias. Nos efluentes coletados, foi realizada análise de K, Ca, Mg e Na, e os dados obtidos, submetidos à análise multivariada, a 5% de probabilidade. Os resultados indicaram efeito significativo para as variáveis K, Ca, Mg e Na com respeito ao solo, dose e tempo de incubação, exceto o Na para a causa de variação solo. De maneira geral, os menores valores das concentrações de cátions presentes nos lixiviados foram obtidos no Nitossolo, maior fração argila, seguido do Espodossolo devido ao horizonte espódico. Os valores dos cátions do lixiviado, comparados com os presentes na vinhaça in natura, foram significativamente reduzidos, indicando que os solos tiveram elevado poder de retenção.

Qualidade do percolado de solos que receberam vinhaça em diferentes doses e tempo de incubação

Neste estudo, objetivou-se avaliar a qualidade do percolado de solos que receberam doses de vinhaça em diferentes tempos de incubação. Para isto, foram reproduzidos, em 27 colunas de PVC de 20 x 110 cm (diâmetro x altura) solos classificados como Nitossolo Háplico, Argissolo Amarelo e Espodossolo Cárbico, com horizontes, espessuras e densidades semelhantes aos do solo original. Os solos foram tratados com vinhaça em doses equivalentes a 0 (Testemunha), 350 e 700 m³ ha-1 submetidos aos tempos de incubação de 30 e 60 dias. Os efluentes coletados foram analisados quanto a DBO5, DQO, CE, SDT e pH. Os resultados indicaram que as variações verificadas nos parâmetros analisados, decorrentes da aplicação da vinhaça ao solo, não trazem maiores preocupações quanto às questões ambientais visto que, quando comparados os valores do percolado com os da vinhaça in natura, os solos, apesar de apresentarem diferentes texturas e, conseqüentemente, diferentes propriedades físico-químicas, mostraram elevado poder de retenção, diminuindo sobremaneira a possibilidade do resíduo causar poluição às águas subsuperficiais.

New functionalities in cellulosic fibers developed by chemical modification

This paper gives an overview of the current state in the field of cellulosic fibers functionalization by chemical modification. The emphasis is placed on the selective (periodate and TEMPO oxidation) and non-selective (permanganate and peroxide) cellulose oxidation, non-conventional methods for obtaining man-made cellulosic fibers, methods for obtaining antimicrobial cellulosic fibers, as well as method for obtaining two-component polysaccharide fibers. To provide evidence on the achieved functionalities we mainly used capillary rise method, moisture and iodine sorption method, water retention power, NaOH uptake, different ions sorption, Cu-number, carbonyl-and carboxyl-selective labelling and antimicrobial tests.