Design and Implementation of a High-Performance and Complexity-Effective VLIW DSP for Multimedia Applications

This paper presents the design and implementation of a novel VLIW digital signal processor (DSP) for multimedia applications. The DSP core embodies a distributed & ping-pong register file, which saves 76.8% silicon area and improves 46.9% access time of centralized ones found in most VLIW processors by restricting its access patterns. However, it still has comparable performance (estimated in cycles) with state-of-the-art DSP for multimedia applications. A hierarchical instruction encoding scheme is also adopted to reduce the program sizes to 24.1∼26.0%. The DSP has been fabricated in the UMC 0.13 μm 1P8M Copper Logic Process, and it can operate at 333 MHz while consuming 189 mW power. The core size is 3.2 × 3.15 mm² including 160 KB on-chip SRAM.

Synthesis and Inhibition Study of Bicyclic Iminosugar-Based Alkaloids,Scaffolds, and Libraries towards Glucosidase

A small library of bicyclic iminosugar-based alkaloids and scaffolds possessing a polyhydroxylated pyrrolidine and a varied ring skeleton have been synthesized. Through rapid diversification of the scaffold via an amide coupling with random carboxylic acids, structurally diverse bicyclic iminosugar-based libraries were prepared with substituent diversity, core diversity, and configurational diversity. This discovery process allowed us to efficiently sieve out potent and specific glycosidase inhibitors, and a bicyclic, conformationally restricted iminosugar was demonstrated to be more potent than the monocyclic ones in this study. The most potent and selective inhibitor discovered was found to have a K_i value of 71 nM against α-glucosidase.     

Differentiation Effects of Platelet-Rich Plasma Concentrations on Synovial Fluid Mesenchymal Stem Cells from Pigs Cultivated in Alginate Complex Hydrogel

This article studied the effects of platelet-rich plasma (PRP) on the potential of synovial fluid mesenchymal stem cells (SF-MSCs) to differentiate. The PRP and SF-MSCs were obtained from the blood and knees of pigs, respectively. The identification of SF-MSCs and their ability to differentiate were studied by histological and surface epitopes, respectively. The SF-MSCs can undergo trilineage mesenchymal differentiation under osteogenic, chondrogenic, and adipocyte induction. The effects of various PRP concentrations (0%, 20% and 50% PRP) on differentiation were evaluated using the SF-MSCs-alginate system, such as gene expression and DNA proliferation. A 50% PRP concentration yielded better differentiation than the 20% PRP concentration. PRP favored the chondrogenesis of SF-MSCs over their osteogenesis in a manner that depended on the ratios of type II collagen/type I collagen and aggrecan/osteopontin. Eventually, PRP promoted the proliferation of SF-MSCs and induced chondrogenic differentiation of SF-MSCs in vitro. Both PRP and SF-MSCs could be feasibly used in regenerative medicine and orthopedic surgeries.     

Midwave infrared optical zooming design and kinoform degrading evaluation methods

In this study, an optical zooming design method is constructed by ray tracing. The loci of each thin lens is determined utilizing algebraic relationships. A mechanical compensation structure is adapted to stabilize the position of the focal plane. The Gaussian design result is applied for the midwave infrared spectrum, and aberrations can be reduced by controlling the geometric parameters of the thick lens. One hybrid achromatic singlet is introduced utilizing a diffraction optical element. The kinoform surface relief is calculated being the same as its microfabrication process. The effects of the discontinuous zonal profile and the thermal degradation are evaluated.     

CdTe solar cell with industrial Al:ZnO on soda-lime glass

One avenue to enhance CdTe cell performance is to improve the optical transmission of the transparent conductive oxide (TCO)/window layer stack. In this paper, we examine soda-lime float glass coated with an Al-doped ZnO layer and a buffer layer. The possible advantages of using a ZnO-based TCO include reduced surface roughness, improved transparency, and an integrated buffer layer that can be optimized for use in a CdTe PV device. Device processing was modified to address the chemical and thermal differences between the ZnO-based TCO stack produced by Saint-Gobain and the TCOs previously used at the National Renewable Energy Laboratory (NREL). These process modifications produced ~ 8% efficiency for devices without a buffer layer. Incorporation of buffer layers has already produced devices with ~ 11% and > 12% efficiency for CdTe deposition temperatures of 570° and 500°C, respectively.     

Enhanced performance and air stability of 3.2% hybrid solar cells: how the functional polymer and CdTe nanostructure boost the solar cell efficiency

A record high PCE of up to 3.2% demonstrates that the efficiency of hybrid solar cells (HSCs) can be boosted by utilizing a unique mono-aniline end group of PSBTBT-NH(2) as a strong anchor to attach to CdTe nanocrystal surfaces and by simultaneously exploiting benzene-1,3-dithiol solvent-vapor annealing to improve the charge separation at the donor/acceptor interface, which leads to efficient charge transportation in the HSCs.     

Enhancement in insulation and mechanical properties of PMMA nanocomposite foams infused with multi-walled carbon nanotubes

In this study, PMMA/CNTs composite materials with carboxyl-multi walled carbon nanotubes (c-MWNTs) or untreated MWNTs were prepared via in-situ bulk polymerization. The as-prepared PMMA/CNTs composite materials were then characterized by Fourier-Transformation infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The molecular weights of PMMA extracted from PMMA/CNTs composite materials and bulk PMMA were determined by gel permeation chromatography (GPC) with THF used as the eluant. The PMMA/CNTs composite materials were used to produce foams by a batch process in an autoclave using nitrogen as foaming agent. The cellular microstructure, insulation and compressive mechanical properties of PMMA/CNTs composite foams were also investigated in detail. Compared to neat PMMA foam, the presence of CNTs increases in cell density and reduces cell size. The insulation and compressive mechanical properties of PMMA/CNTs composite foams were found to improve substantially those of neat PMMA foam. In particular, 22.6% decrease in thermal conductivity, 19.7% decrease in dielectric constant and 160% increase in compressive modulus were observed with the addition of 0.3 wt% carboxyl-multi walled carbon nanotubes (c-MWNTs).     

A new method for volume segmentation of PET images, based on possibility theory

18F-fluorodeoxyglucose positron emission tomography (18FDG PET) has become an essential technique in oncology. Accurate segmentation and uptake quantification are crucial in order to enable objective follow-up, the optimization of radiotherapy planning, and therapeutic evaluation. We have designed and evaluated a new, nearly automatic and operator-independent segmentation approach. This incorporated possibility theory, in order to take into account the uncertainty and inaccuracy inherent in the image. The approach remained independent of PET facilities since it did not require any preliminary calibration. Good results were obtained from phantom images [percent error =18.38% (mean) ± 9.72% (standard deviation)]. Results on simulated and anatomopathological data sets were quantified using different similarity measures and showed the method was efficient (simulated images: Dice index =82.18% ± 13.53% for SUV =2.5 ). The approach could, therefore, be an efficient and robust tool for uptake volume segmentation, and lead to new indicators for measuring volume of interest activity.     

Parallel Architecture Core (PAC)—the First Multicore Application Processor SoC in Taiwan Part I: Hardware Architecture &; Software Development Tools

In order to develop a low-power and high-performance SoC platform for multimedia applications, the Parallel Architecture Core (PAC) project was initiated in Taiwan in 2003. A VLIW digital signal processor (PACDSP) has been developed from a proprietary instruction set with multimedia-rich instructions, a complexity-effective microarchitecture with an innovative distributed & ping-pong register organization and variable-length VLIW encoding, to a highly-configurable soft IP with several successful silicon implementations. A complete toolchain with an optimizing C compiler has also been developed for PACDSP. A dual-core PAC SoC has been designed and fabricated, which consists of a PACDSP core, an ARM9 core, scratchpad memories, and various on-chip peripherals, to demonstrate the outstanding performance and energy efficiency for multimedia processing such as the real-time H.264 codec. The first part of the two introductory papers of PAC describes the hardware architecture of the PACDSP core, its software development tools, and the PAC SoC with dynamic voltage and frequency scaling (DVFS).     

Nondestructive determination of electromagnetic parameters ofdielectric materials at X-band frequencies using a waveguide probesystem

An accurate technique used to measure complex permittivity and permeability of isotropic materials simultaneously has been developed by employing a flanged open-ended rectangular waveguide probe over a frequency range of 8-12 GHz. Two coupled integral equations for the aperture electric field are formulated and solved numerically using Galerkin's method. A series of experiments has been conducted, and the calibration of the probe system using an adjustable shorter is explained. The inverse results on the electromagnetic (EM) properties of various materials (including solid and liquid materials) based on the measured reflection coefficients of the incident dominant mode are presented. It is also shown that the EM parameters of isotropic materials having low complex permittivities can be determined accurately, while those with higher complex permittivities cause larger measurement errors