Search

This paper presents a 28-nm 256-kb 6T static random access memory operating down to near-threshold regime. The cell array is built on foundry 4-by-2 mini-array with split single-ended large signal sensing to enable an ultra-short local bit-line of 4-b length to improve variation tolerance and performance, and to reduce disturb while maintaining manufacturability. The design employs threshold power gating to facilitate lower NAP (Sleep) mode voltage/power and faster wake-up for the cell array, and low-swing global read bit-line (GRBL) with integrated low-swing voltage precharger to improve read performance and reduce the dynamic read power. A cell Vtrip-tracking write-assist (VTWA) lowers the selected sub-array supply to cell inverter trip voltage to enhance write-ability while providing PVT tracking capability to ensure adequate data retention margin for unselected cells in the selected sub-array. The 256-kb test chip is implemented in UMC 28-nm high- $\kappa $ metal-gate (H \kappa $ MG) CMOS technology with macro area of 1058.22\times 374.76~\mu \text{m}^{2} . Error-free full functionality is achieved from 0.9 down to 0.5 V (limited by read VMIN without redundancy. The low-swing GRBL reduces dynamic power by 6.5% (8.0%) at 0.9 V (0.6 V). The VTWA improves the write VMIN by 75 mV (from 0.525 to 0.45 V). The measured maximum operation frequency is 735 MHz (20 MHz) at 0.9 V (0.5 V), TT corner, 25°. [ABSTRACT FROM AUTHOR]

Abstract: In the past, the choices of β values to be applied to find the β-reducts in VPRS for an information system are somewhat arbitrary. In this study, a systematic method which bridges the fuzzy set methodology and probabilistic approach of RS to solve the threshold value β determination problem in variable precision rough sets (VPRS) is proposed. Different from the existing probabilistic methods, the proposed method relies on the fuzzy membership degrees of each attribute of the objects to calculate β. The proposed method gives the membership degrees and fuzzy aggregation operators the probabilistic interpretations. Based on the probabilistic interpretations, the threshold value β of VPRS is directly derived from fuzzy membership degree by Implication Relations and Fuzzy Algorithms, in which the membership degrees are obtained by the standard Fuzzy C-means method. The argument is that errors of system classification would occur in the fuzzy-clustering phase prior to information classification, therefore the threshold value β should be constrained by the probability of belongingness of an object to the fuzzy clusters, i.e., through the values of membership functions. A few examples are given in the paper to demonstrate the differences with other β-determining methods. [Copyright &y& Elsevier]

The purpose of this research is to investigate the effect of tanshinone IIA, an extract of the Chinese medicine Que Xie Hua Yu Tang, on uric acid nephropathy (UAN) and to elucidate the underlying mechanisms. UAN rat model was established. Fifty UAN rats were randomly allocated into 5 groups: adenine-treated group, allopurinol-treated group, and low/middle/high dose of tanshinone IIA-treated groups. Meanwhile, another 10 rats were used as normal controls. Serum uric acid (UA), blood urea nitrogen (BUN), serum creatinine (Scr), MCP-1, and IL-1β levels were measured. Histological staining was performed. Comparison between the adenine group and treatment (allopurinol and tanshinone IIA) groups showed compound treatment could attenuate the inflammation status of the kidneys and decrease serum UA levels. Among different kinds of medicine, tanshinone IIA had similar effects as allopurinol and exerted anti-inflammatory and renal protective effect in a dose-dependent manner. Furthermore, we found tanshinone IIA alone could also inhibit urate-induced MCP-1 and IL-1β overexpression both in vivo and in vitro, accompanied with inhibition of NF-κB translocation from cytosome to nucleus. Tanshinone IIA could protect rats from uric acid-induced kidney damage, probably by attenuating renal inflammatory status. [ABSTRACT FROM AUTHOR]