Data Randomization Scheme for Endurance Enhancement and Interference Mitigation of Multilevel Flash Memory Devices

In this letter, we propose a data randomization scheme for endurance and interference mitigation of deeply‐scaled multilevel flash memory. We address the relationships between data patterns and the raw bit error rate. An on‐chip pseudorandom generator composed of an address‐based seed location decoder is developed and evaluated with respect to uniformity. Experiments performed with 2x‐nm and 4x‐nm NAND flash memory devices illustrate the effectiveness of our scheme. The results show that the error rate is reduced up to 86% compared to that of a conventional cycling scheme. Accordingly, the endurance phenomenon can be mitigated through analysis of interference that causes tech shrinkage.     

Plasma etching optimization of oxide/nitride/oxide interpolydielectric breakdown time in flash memory devices

The breakdown time of flash memory oxide/nitride/oxide (ONO) layer t_bd under positive constant current stressing has been found to be closely related to the cumulative extent of (over)etch of the tungsten silicide, control polysilicon, and ONO layers, i.e., Σ(ΛOE). An empirical first-order relation between t_bd and Σ(ΛOE) has been derived to facilitate the plasma etch recipe optimization. This has led to a four-fold increase in the average t_bd across a 200-mm wafer to 208 s. More importantly, the spread in t_bd has been tightened to ~5%, which is down from ~54%     

Does genre type influence choice of video platform? A study of college student use of internet and television for specific video genres

With the introduction of multichannel video programming distributors and different types of video platforms, consumers have more choices of channels and platforms than ever. Specifically, the present study focuses on television and the Internet as video platforms.     

A simple nutrient-tolerance (NT) test for the characterization of the different types of oligocarbotolerant and oligocarbophile water bacteria from non-carbonated mineral water

Comparative determination of the specific growth kinetics in mineral water and low and higher concentrated broths at 20 degrees C of 25 selected Gram-negative bacteria isolated from natural non-carbonated mineral water yielded three groups: (1) facultative oligocarbotolerants--with faster growth in normal broth (In g l-1: yeast extract 2.5; casein peptone 5.0; glucose 1.0); (2) obligate oligocarbotolerants--with equal rates of growth in normal and 1:10 diluted broth; and (3) oligocarbophiles--with faster growth in 1:10 diluted broth and in mineral water. In addition, three nutrient types, 'eu-, meso- and oligotrophic' could be distinguished on the basis of full, weak and no growth in brain-heart infusion broth. Further characterization was made between slow and very slow growth types in 1:10 diluted broth. All 25 isolates were psychrotrophic with a minimum growth temperature below 0 degree C. The optimum and maximum temperatures of growth in 1:10 diluted broth, as determined in a temperature gradient incubator were between 20 and 32, and between 29 and 34 degrees C with an average of 26 and 31 degrees C, respectively. Based on these results a very simple nutrient-tolerance test was proposed. After inoculation of the three media, 1:10 diluted broth, normal broth and brain-heart infusion, it is only necessary to check whether or when visible turbidity occurs during 2 weeks incubation at 20 degrees C. This allows additional characterization of bacteria from natural mineral water, which are often difficult to identify, on the basis of growth characteristics in various types of nutrient media.     

Correlation analysis for non-invasive quantitative monitoring of biological activity of recombinant enzyme using green fluorescence protein in Escherichia coli under various culture environments

Monitoring of biological activity for target enzyme is important for its production in recombinant expression systems. Previously, we demonstrated that green fluorescent protein (GFP) as a fusion partner is successfully tooled for facile, in vivo, and non-invasive quantification of target enzyme levels based on a linear relationship between GFP fluorescence and enzyme (chloramphenicol acetyltransferase; CAT) activity. Here, we investigated the effects of culture environmental variations (initial glucose amount, surface aeration, and inducer concentration) on correlation between GFP fluorescence and CAT activity, and established a general linear correlation as a unique criterion for quantitative monitoring of CAT biological activity. This general correlation for GFP fusion strategy can be applied for non-invasive and on-line monitoring of recombinant enzyme production under various culture conditions without further experimental calibrations.     

Tertiary treatment of biologically treated piggery wastewater using vibratory shear-enhanced RO membrane.

This study presents a good example for the tertiary treatment of biologically treated piggery wastewater using vibratory shear enhanced RO membrane (VSEP RO). Through a simple process combination, utilizing Bioceramic SBR(BCS) and VSEP RO, at Gimhae plant livestock wastewater is treated excellently to meet the strict effluent standards. Application of RO membrane directly to the biologically treated effluent has been successful without any pretreatment to reduce high suspended solids. The combination of VESP UF followed by RO filtration processes produced a higher recovery rate in the 3-week pilot test.     

Antioxidant activities of phlorotannins purified from Ecklonia cava on free radical scavenging using ESR and H2O2-mediated DNA damage

The potential antioxidant activities of three phlorotannins (phloroglucinol, eckol and dieckol) purified from Ecklonia cava collected in Jeju Island were investigated to evaluate their potential value as the natural products for foods or cosmetic application. In this study, antioxidant activities were measured by electron spin resonance spectrometry (ESR) technique for scavenging effects of free radicals such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), alkyl, hydroxyl (HO^•) and superoxide anion radical (O₂ ^•−) and by comet assay for protecting effects against H₂O₂-mediated DNA damage. The results show that all the phlorotannins have the potential DPPH, alkyl, hydroxyl and superoxide radical scavenging activities. Especially, eckol samples scavenged around 93% of DPPH at 0.25, 0.5, 1 mg/mL of concentrations and were higher than the other phlorotannins, such as phloroglucinol and dieckol samples. Also, protecting effects of the phlorotannins against H₂O₂-mediated DNA damage increased with increased concentrations of the samples in the L5178 mouse T-cell lymphoma cell lines (L5178Y-R). In conclusion, these results suggest that the three phlorotannins purified from E. cava have the potential inhibitory effect on H₂O₂-mediated DNA damage and harmful free radicals and can be used as antioxidants in cosmetic, foods and drug industry.     

Cycling performance of a lithium-ion polymer cell assembled by in-situ chemical cross-linking with fluorinated phosphorous-based cross-linking agent

Lithium-ion polymer cells composed of a carbon anode and a LiCoO₂ cathode are assembled with a gel polymer electrolyte cured by in-situ chemical cross-linking with novel cross-linking agents. The strong interfacial adhesion between the electrodes and the porous polyethylene membrane by the chemical cross-linking results in the stable capacity retention of the cell. However, a reduction in the ionic mobility in both the electrolyte and the electrodes adversely affects the high rate performance of the cell. These results imply that proper control of the cross-linking density in the cell is imperative for achieving good capacity retention and high rate performance of the cell.     

Mixing enhancement in crisscross micromixer using aperiodic electrokinetic perturbing flows

A novel method is proposed for enhancing the mixing performance in a crisscross micromixer by means of aperiodic time-varying electrokinetic perturbing flows. In the proposed approach, the aperiodic oscillating source used to modulate the perturbing electric potential is derived using the Sprott system. The effects of the perturbation conditions and micromixer geometry parameters on the fluid flow characteristics and mixing performance are analyzed by means of numerical simulations. The results show that irregularly-alternating flow recirculation structures are induced within the lateral channels of the micromixer, which cause a repeated stretching and folding of the species streams in the main channel and enhance the mixing performance as a result. It is shown that an effective improvement in the mixing performance can be obtained through a suitable specification of the scaling factor in the Sprott system. Furthermore, it is shown that the mixing performance can be further enhanced by assigning suitable values to the micromixer geometry parameters or by reducing the ratio of the main channel flow velocity to the lateral channel flow velocity. Overall, the numerical results show that an average mixing efficiency of more than 90% can be obtained by specifying the scaling factor in the Sprott system as 7.5, the ratio of the main channel velocity to the lateral channel velocity as 0.25, the separation distance between the lateral channels as equal to half the width of the main channel, and the width of the lateral channels as equal to the width of the main channel.     

Characterizations of gun barrel vibrations of during firing based on shock response analysis and short-time Fourier transform

The behavior of shock vibration for a medium caliber gun barrel was experimentally investigated and then, numerical modal analysis, a signal processing technique as well shock response analysis were carried out en route to the detailed analyses. This approach was initiated by identifying mode frequencies from the numerical model and thus the frequencies were clarified using the periodogram together with the spectrogram based on the time frequency analysis. A shock response analysis was employed to draw more physical interpretations regarding the barrel behaviors due to firing shock. In this paper, therefore, the overall process of shock vibration analysis was demonstrated for analyzing the shock behavior of the gun barrel.