Area-efficient high-throughput MAP decoder architectures

Iterative decoders such as turbo decoders have become integral components of modern broadband communication systems because of their ability to provide substantial coding gains. A key computational kernel in iterative decoders is the maximum a posteriori probability (MAP) decoder. The MAP decoder is recursive and complex, which makes high-speed implementations extremely difficult to realize. In this paper, we present block-interleaved pipelining (BIP) as a new high-throughput technique for MAP decoders. An area-efficient symbol-based BIP MAP decoder architecture is proposed by combining BIP with the well-known look-ahead computation. These architectures are compared with conventional parallel architectures in terms of speed-up, memory and logic complexity, and area. Compared to the parallel architecture, the BIP architecture provides the same speed-up with a reduction in logic complexity by a factor of M, where M is the level of parallelism. The symbol-based architecture provides a speed-up in the range from 1 to 2 with a logic complexity that grows exponentially with M and a state metric storage requirement that is reduced by a factor of M as compared to a parallel architecture. The symbol-based BIP architecture provides speed-up in the range M to 2M with an exponentially higher logic complexity and a reduced memory complexity compared to a parallel architecture. These high-throughput architectures are synthesized in a 2.5-V 0.25-/spl mu/m CMOS standard cell library and post-layout simulations are conducted. For turbo decoder applications, we find that the BIP architecture provides a throughput gain of 1.96 at the cost of 63% area overhead. For turbo equalizer applications, the symbol-based BIP architecture enables us to achieve a throughput gain of 1.79 with an area savings of 25%.     

Toxoplasma gondii GRA9 Regulates the Activation of NLRP3 Inflammasome to Exert Anti-Septic Effects in Mice

Dense granule proteins (GRAs) are essential components in Toxoplasma gondii, which are suggested to be promising serodiagnostic markers in toxoplasmosis. In this study, we investigated the function of GRA9 in host response and the associated regulatory mechanism, which were unknown. We found that GRA9 interacts with NLR family pyrin domain containing 3 (NLRP3) involved in inflammation by forming the NLRP3 inflammasome. The C-terminal of GRA9 (GRA9C) is essential for GRA9–NLRP3 interaction by disrupting the NLRP3 inflammasome through blocking the binding of apoptotic speck-containing (ASC)-NLRP3. Notably, Q200 of GRA9C is essential for the interaction of NLRP3 and blocking the conjugation of ASC. Recombinant GRA9C (rGRA9C) showed an anti-inflammatory effect and the elimination of bacteria by converting M1 to M2 macrophages. In vivo, rGRA9C increased the anti-inflammatory and bactericidal effects and subsequent anti-septic activity in CLP- and E. coli- or P. aeruginosa-induced sepsis model mice by increasing M2 polarization. Taken together, our findings defined a role of T. gondii GRA9 associated with NLRP3 in host macrophages, suggesting its potential as a new candidate therapeutic agent for sepsis.     

Investigation on removal of hardness ions by capacitive deionization (CDI) for water softening applications

Capacitive deionization (CDI) for removal of water hardness was investigated for water softening applications. In order to examine the wettability and pore structure of the activated carbon cloth and composites electrodes, surface morphological and electrochemical characteristics were observed. The highly wettable electrode surface exhibited faster adsorption/desorption of ions in a continuous treatment system. In addition, the stack as well as unit cell operations were performed to investigate preferential removal of the hardness ions, showing higher selectivity of divalent ions rather than that of the monovalent ion. Interestingly, competitive substitution was observed in which the adsorbed Na ions were replaced by more strongly adsorptive Ca and Mg ions. The preferential removal of divalent ions was explained in terms of ion selectivity and pore characteristics in electrodes. Finally, optimal pore size and structure of carbon electrodes for efficient removal of divalent ions were extensively discussed.     

A linear motor damper for vibration control of steel structures

A hybrid mass damper based on the linear motor principle is developed to suppress structural vibration. We will call it a linear motor damper in this paper. This paper deals with the design, analysis, and manufacture of the linear motor damper. It consists of the NdFeB permanent magnets, a coil-wrapped nonmagnetic hollow rectangular structure, an iron core, mechanical springs, and so on. It is designed to be able to move the auxiliary mass of 1500 kg, up to ±250 mm stroke. A series of performance tests for the linear mass damper with H_∞ robust controller are carried out on a steel frame structure. Through performance tests, it is confirmed that the developed hybrid mass damper has reliable feasibility as a control device for structural control. In addition, the linear motor damper is more economical than both hydraulic and electric motor driving mass damper with respect to simple structure and low maintenance cost.     

Preparation of ion exchanger layered electrodes for advanced membrane capacitive deionization (MCDI)

A noble electrode for capacitive deionization (CDI) was prepared by embedding ion exchanger onto the surface of a carbon electrode to practice membrane capacitive deionization (MCDI). Bromomethylated poly (2, 6-dimethyl-1, 4-phenylene oxide) (BPPO) was sprayed on carbon cloth followed by sulfonation and amination to form cation exchange and anion exchange layers, respectively. The ion exchange layers were examined by Scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FT-IR). The SEM image showed that the woven carbon cloth was well coated and connected with BPPO. The FT-IR spectrum revealed that sulfonic and amine functional groups were attached on the cationexchange and anionexchange electrodes, respectively. The advantages of the developed carbon electrodes have been successively demonstrated in a batch and a continuous mode CDI operations without ion exchange membranes for salt removal using 100 mg/L NaCl solution.     

Optimal design of multi-stage porous plate collection system

The main objective of this study was to investigate the optimal design parameters of a multi-stage porous plate system, numerically and experimentally. Characteristics of pressure drop and collection efficiency are analyzed with the operation parameters such as the stage number, plate interval, hole diameter and system inlet velocity, etc. In the results, pressure drops of a 5 stage system [2, 2, 3, 2, 2mm] at v_s,in=1.0, 1.2 m/s are shown as 296, 428 mmH₂O by the numerical simulation and 259, 399 mmH₂O in the experiment. For 5 stage [2, 2, 3, 2, 2 mm] and v_s,in=1.0 m/s, the overall collection efficiencies with the plate interval 4, 10, 15 mm are estimated as 99.5, 96.0, 92.8% computationally and 97.9, 89.2, 85.3%, showing slightly lower efficiency compared to the numerical results due to the particle rescattering effect, experimentally.     

Characteristics of an electrostatic precipitator for submicron particles using non-metallic electrodes and collection plates

We have developed a novel ESP that uses an anticorrosive carbon brush precharger and plastic collection plates into which metallic films are inserted. The collection efficiency of the ESP was measured using ultrafine KCl particles by varying the applied voltages, the number of channels in the charger, the gap between the collection plates, and the air flow rates. Tests of loading and cleaning on the collection plates were also conducted using JIS class # 8 dusts and KCl particles.The experimental results showed that the precharger (400×400×800 mm³) generated a lot of unipolar ions whilst producing negligible concentrations of ozone (<5 ppb), and that when the ESP was operated with 16 channels of ionizers and a 10 mm gap between the collection plates (400×400×185 mm³), it removed more than 95% of the ultrafine particles with a power consumption of only 5 W and a pressure drop of 5 Pa per 1200 m³/h at 2 m/s. It was also shown that by increasing the applied voltage and the number of channels in the charger, and by decreasing the gap between the collection plates, an improvement in the collection efficiency of the ESP could be achieved for a scale-up. It was also found that the collection efficiency for the ultrafine particles fell from approximately 95% to 50% after dust loading with 100 mg/m³ of the JIS dusts for 2 h, but then recovered perfectly to the efficiency of the initial state after the collection plates were sprayed with water at 25 L/min for 4 min.     

电机工程中的坐标变换

本文简述了电机工程中所用坐标变换的一般方法，由此导出电机工程中常用的几种坐标系统。最后列表展示这些坐标系统间的交换关系。     

Conformal electroless deposition of Cu seed layer on a 60-nm trench pattern modified with a self-assembled monolayer

We have developed a novel activation technique for the conformal electroless deposition (ELD) of Cu on a SiO₂ substrate modified with an organic self-assembled monolayer. The SiO₂ substrate was modified with amine groups using 3-aminopropyltriethoxysilane and Au nanoparticles (AuNPs) to form a uniform, continuous catalyst for ELD. The Au catalytic layer formed on the amine-SiO₂ substrate was stabilized by electrostatic interactions between the positively charged protonated-amine self-assembled monolayer (SAM) and negatively charged AuNPs. Cu films were then electrolessly deposited on Au-catalyzed SiO₂ substrates. The Cu seed layer formed by this method showed a highly conformal and continuous structure. Cu electrodeposition on the 60-nm trench was demonstrated using an acid cupric sulfate electrolyte containing chloride, polyethylene glycol 4000 and bis(3-sulfopropyl)disulfide. The resulting electroplated Cu showed excellent filling capability and no voids or other defects were observed in a 60-nm trench pattern.