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Yue Xu,1,* Weiyin Chen,1,* Zeran Chen,2 Mengyuan Huang,1 Fang Yang,1 Yang Zhang1 1Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, People’s Republic of China; 2School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu Sichuan, 610041, People’s Republic of China*These authors contributed equally to this workCorrespondence: Fang YangHospital of Chengdu University of Traditional Chinese Medicine, No. 39 Shi-er-qiao Road, Chengdu, 610075, People’s Republic of ChinaTel/Fax +86 28- 87783481Email yfgreens2013@163.comYang ZhangHospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, People’s Republic of ChinaEmail zhangyang@cdutcm.edu.cnObjective: The traditional Chinese medicine (TCM) formulation Xiaoyao San (XYS) has a good clinical effect in treating ischemic stroke (IS). We explored the mechanism and material basis of XYS in IS treatment.Methods: Network pharmacology was used to construct a network of XYS components and IS targets. R software was used to analyze the biological process and pathway analysis of the targets of XYS in IS treatment. In vitro, a model of apoptosis of PC12 cells induced by oxygen-glucose deprivation/reperfusion (OGD/R) was established to evaluate the neuroprotective effect of XYS and its influence on the expression of apoptotic protein-related genes. The affinity between the potentially active compounds in XYS and apoptotic proteins was evaluated by molecular docking.Results: XYS was shown to have 136 chemical components that exert potential anti-IS activity by acting on 175 proteins. Bioinformatics analysis showed that apoptosis and the phosphoinositide 3-kinase/protein kinase B (PI3K-Akt) signaling pathway were the main signaling pathways of XYS. In vitro experiments showed that XYS could improve the effect of OGD/R on PC12-cell activity (EC50 = 0.43 mg/mL) and inhibit apoptosis. The main mechanisms were related to the improvement of oxidative stress and regulation of apoptosis-related gene expression. Molecular docking showed that C22, C102 and other components in XYS had a strong affinity with apoptosis-related proteins.Conclusion: Network pharmacology, in vitro experiments, and molecular docking were used, for the first time, to study the material basis and molecular mechanism of XYS in IS treatment from the perspective of multiple targets and multiple pathways. We provided a new approach for the future study of TCM formulations in the treatment of complex diseases.Keywords: apoptosis, neuroprotection, biological function, pharmacological mechanism

Purpose: To investigate the neuroprotective effect of Shenxiong Drop Pill (SXDP) pretreatment on rats with middle cerebral artery occlusion (MCAO) in rats, and the mechanism involved.Methods: Ninety-nine SD rats were randomly assigned to 4 groups: control group, MCAO group, shamoperated group and SXDP group. The MCAO model was established via thread occlusion. Rats in the SXDP group was administered SXDP 7 days before induction of MCAO. Neurological deficit score (NDS) was determined using Bederson's neurological behavioral scoring method, while cerebral infarction volume was measured using TTC staining. Integrated optical density (IOD) of Nissl Body was evaluated via Nissl staining. Brain water content was measured using dry-wet method. The expression level of AQP4 in brain tissues was determined using immunocytochemistry.Results: The SXDP treatment resulted in significant reduction in NDS, marked improvement in IOD of Nissl Body, and significant reductions in cerebral infarction volume, brain water content, and expression level of AQP4, relative to control (p< 0.05).Conclusion: These results suggest that SXDP pretreatment exerts neuroprotective effect against cerebral ischemia in rats by decreasing in cerebral edema through a mechanism involving downregulation of the expression of AQP4. Keywords: Middle cerebral artery occlusion, Cerebral ischemia, Aquaporins-4, Cerebral edema, Neuroprotection

Purpose: To investigate the effect of Shenxiong Drop Pill (SXDP) on cerebral infarction (CI) in rats, and the involvement of anti-inflammatory response in the process.Methods: Rats were sacrificed at three different time points, viz, 24, 48 and 72 h after establishment of CI model. Neurological deficit score (NDS) was determined using Bederson’s neurological behavioral scoring method, whereas triphenyltetrazolium chloride (TTC) staining was used to show brain injury. The integrated optical density (IOD) of Nissl bodies and caspase-3-positive nerve cells were measured with Nissl staining and SP kit, respectively. The mRNA expression of intercellular adhesion molecule 1(ICAM-1) was determined using reverse transcription-polymerase chain reaction (RT-PCR).Results: SXDP produced neuroprotective effect at high, medium, and low doses. The infarct volumes in the high-, medium- and low-dose SXDP, and cyclophosphamide groups were significantly reduced at each time point. Different doses of SXDP significantly reduced the mRNA expression of ICAM-1 and the IOD of caspase-3.Conclusion: These results indicate that SXDP exerts neuroprotective effects against ischemic injury by negatively regulating ICAM-1/caspase-3 downstream of inflammatory and apoptosis pathways.

The present study discusses a novel ultrasound promoted amination technique to functionalize graphene oxide (GO) for CO2 adsorption. Graphene oxide was synthesized following the modified Hummer’s method. The developed functionalization technique integrates the advantages of low-frequency ultrasonic physical activation with the chemical functionalization using tetraethylenepentamine (TEPA). Acoustic treatment exfoliates the clusters of graphene oxide and enhances the surface area for the subsequent amine functionalization and CO2 adsorption. Changes in textural properties, surface functionalities, thermal stability, and elemental compositions were examined before and after activation of graphene oxide. The characterization results revealed substantial increment of N content, from 0.08 in pristine to 4.84% in functionalized GO and the subsequent reduction in surface area from 289 to 198 m2/g in the functionalized GO, indicating attachment of TEPA to GO structure. CO2 adsorption experiments were conducted under diluted CO2 with the partial pressure of 0.10 atm. at 338 K and the results revealed that ultrasonic-TEPA activated GO possessed enhanced adsorption capacity of 1.2 mmol g−1 over pristine GO. While pristine GO could only achieve the maximum adsorption capacity of 0.3 mmol g−1 at 303 K. Besides, the sonochemically modified adsorbent showed stable cyclic adsorption-regeneration performance with only 1% reduction in adsorption capacity after 10 cycles. Finally, the effectiveness of the developed physicochemical activation technique was determined by comparing its adsorption capacity with the adsorbents found from literature.

The main objective of a series of our researches is to develop a novel acoustic-based method for activation of biochar. This study investigates the capability of biochar in adsorbing Ni(II) as a hazardous contaminant and aims at enhancing its adsorption capacity by the addition of extra nitrogen and most probably phosphorous and oxygen containing sites using an ultrasono-chemical modification mechanism. To reach this objective, biochar physically modified by low-frequency ultrasound waves (USB) was chemically treated by phosphoric acid (H3PO4) and then functionalized by urea (CO(NH2)2). Cavitation induced by ultrasound waves exfoliates and breaks apart the regular shape of graphitic oxide layers of biochar, cleans smooth surfaces, and increases the porosity and permeability of biochar’s carbonaceous structure. These phenomena synergistically combined with urea functionalization to attach the amine groups onto the biochar surface and remarkably increased the adsorption of Ni(II). It was found that the modified biochar could remove > 99% of 100 mg Ni(II)/L in only six hours, while the raw biochar removed only 73.5% of Ni(II) in twelve hours. It should be noted that physical treatment of biochar with ultrasound energy, which can be applied at room temperature for a very short duration, followed by chemical functionalization is an economical and efficient method of biochar modification compared with traditional methods, which are usually applied in a very severe temperature (>873 K) for a long duration. Such modified biochars can help protect human health from metal-ion corrosion of degrading piping in cities with aging infrastructure.

This study investigates the potential of cow dung, an animal manure, as a binder to enhance the physicochemical properties of the base pellet (a mixture of wheat straw and rice husk). In the first step, preliminary experiments were performed to select the best composition of wheat straw and rice husk for the base pellet. The selection was based on calorific value. Subsequently, the effect of operating parameters such as varying compositions of cow dung (0–100%), molasses concentration (0–100%) and drying time (12–48 h) was investigated. Thus, Central Composite Design using Response Surface Methodology was used to investigate the proximate analysis, calorific value, bulk density and durability of biomass pellets. The experimental results suggested that the addition of cow dung into the base pellet resulted in the increase of volatile matter, ash content, bulk density and durability of the base pellet. As a result, the maximum calorific value of 14.98 MJ/kg, moisture content of 3.37%, volatile matter of 45.49%, ash content of 31.38%, bulk density of 108990 kg/m3 and durability of 95% were obtained. However, optimization of operating parameters was performed to optimize the ash percentage. With the pellet composition of 8.5% (base pellet composition of 90% wheat straw and 10% rice husk), molasses concentration of 50% and drying time of 12 h, 52% reduction in ash content and 2.3% increase in calorific value were obtained at the cost of 38% reduction in the bulk density and insignificant reduction in durability of the produced pellet. Therefore, the use of waste material like cow dung as a binder can be considered as a sustainable approach to improve the physicochemical properties especially durability of biomass pellets. Thus, it can effectively be used to fulfill the energy and heating requirement of rural areas.

The present study examined the effect of pyrolysis temperature on the physicochemical properties of biochar, activation process and carbon capture. Two different categories of biochars were synthesized from herbaceous (miscanthus and switchgrass) or agro-industrial (corn stover and sugarcane bagasse) feedstock under four different pyrolysis temperatures- 500, 600, 700 and 800 oC. The synthesized biochars underwent sono-amination activation comprising low-frequency acoustic treatment followed by amine functionalization to prepare adsorbents for CO2 capture. As per the elemental analysis, the elevated pyrolysis temperature resulted in increased %C and %ash contents and reduced %N contents of biochar. The textural analysis exhibited almost 3-times enhancement of micro surface area and pore volume upon increasing the pyrolysis temperature from 500 to 700 oC, though further increase to 800 oC reduced the micro-porosity and the surface area. The intermediate temperatures of 600 and 700 oC revealed the highest interactions with ultrasound-amination, which significantly intensified CO2 adsorption. Accordingly, the CO2 capture capacity of sono-aminated biochars synthesized at 600 and 700 oC were almost 200% greater than that of raw biochars. There were 127-159% and 115-151% increases in adsorption capacity of biochars synthesized at 800 and 500 oC upon ultrasono-amine functionalization. Miscanthus biochar synthesized at 700 oC and treated sono-chemically demonstrated the highest adsorption ability of 2.89 mmol/g at 70 oC and 0.10 atm partial pressure, which is 211% higher than its pristine condition. The superior adsorption capacity of miscanthus (at 700 oC) can be attributed to its large surface area (324.35 m2/g), high carbon content (84%), and low ash content (4.9%), as well as its %N content after sono-amination that was twice that of raw char.

The objectives of a series of our researches are to determine the feasibility of applying ultrasonic pretreatment prior to biochar gasification. As per the initial results, the heating value (HV) of biochar significantly increased after acoustic treatment in water with dissolved CO2 (AIChE Journal, 2014;60:1054–1065). Accordingly, emphasis of the current work is placed on the parameters governing the HV of biochar in the early stage of the treatment. Switchgrass and miscanthus biochars were treated under different conditions. The reactant ratio, biochar:water:CO2, exhibited profound impacts on the synergism. The highest (but not yet systematically optimized) ratio of HV increase (or HV Gain, HG) to ultrasound energy supplied (ES) takes place when biochar-to-water ratio, or BC:W, equals 0.06 g/ml. The observed HG/ES is about 10, suggesting that the energy consumption is only a fraction of the acoustic energy supplied. Miscanthus biochar’s HV increases by up to 4.6% after treatment at 5% amplitude for 135 s (HG = 33 cal/g). For the same run, miscanthus biochar's H content increased by 42.7%. Changes in HV can be mediated by mineral leaching, C or H fixation, or O content loss. Mineral leaching is influenced by pH and CO2 concentration. CO2 and water are the sole contributors to C and H gains, respectively. CO2 concentration in the solution during the treatment is also affected by mass transfer limitations, ultrasound power, and design of the three-phase reactor. Increasing the BC:W ratio initially enhances the cavitation nuclei on the fluid/solid surface, and therefore sonolysis. The subsequent decrease in HV with increasing BC:W may be due to the limitation in ultrasound penetration and H supply from water. Carbon and hydrogen fixation may be connected to the formation of H2, CO, formic acid, formaldehyde, and associated radicals during sonolysis of aqueous CO2.

Renewable energy sources e.g. biofuels, are the focus of this century. Economically and environmental friendly production of such energies are the challenges that limit their usages. Microalgae is one of the most promising renewable feedstocks. However, economical production of microalgae lipid in large scales is conditioned by increasing the lipid content of potential strains without losing their growth rate or by enhancing both simultaneously. Major effort and advances in this area can be made through the environmental stresses. However, such stresses not only affect the lipid content and species growth (biomass productivity) but also lipid composition. This study provides a comprehensive review on lipid enhancement strategies through environmental stresses and the synergistic or antagonistic effects of those parameters on biomass productivity and the lipid composition. This study contains two main parts. In the first part, the cellular structure, taxonomic groups, lipid accumulation and lipid compositions of the most potential species for lipid production are investigated. In the second part, the effects of nitrogen deprivation, phosphorus deprivation, salinity stress, carbon source, metal ions, pH, temperature as the most important and applicable environmental parameters on lipid content, biomass productivity/growth rate and lipid composition are investigated.

Biochar, known as a byproduct of biomass pyrolysis, was prepared from rice straw (R6), tobacco straw (T6), corn straw (C6), wheat straw (W6), millet straw (M6), and black bean straw (B6) in high purity nitrogen at 600 °C. Chlorine (Cl) non-thermal plasma was used to increase Cl active sites on biochar to promote the mercury removal efficiency. The physio-chemical properties of biochar were characterized by proximate analysis, ultimate analysis, BET, SEM, TGA, FTIR, and XPS. Modification by chlorine plasma increased the Hg0 removal efficiency of the biochar from around 8.0% to 80.0%. The Hg0 adsorption capacity of T6 was 36 times higher after Cl2 plasma modification. Plasma caused the biochar surface to become porous and promoted the thermal stability of the biochar. Sulfur (S) content remained in the range of 0.5–0.7%, elemental/organic sulfur and sulfide were converted to sulfate during plasma treatment. The relative intensity of the oxygen functional groups (C O, C O and C(O) O C) were enhanced, while the content of oxygen (O) in biochar decreased. The main reason for the improved mercury removal efficiency by modified biochars was attributed to the increased number of C Cl groups on the surface of the biochars induced by Cl2 plasma. The C Cl groups functioned as activated sites and promoted the Hg0 removal efficiency.

VLSI realization of video compression is the key to real-time high-definition 3D communication systems. The newly established multiview video coding standard, as an extension profile of H.264/AVC, draws more and more attention for its high compression ratio and free-viewpoint support. Besides providing the 3D experience, multiview video can also give users complete scene perception. However, the multiple-viewpoint throughput requirement of MVC increase the complexity and hardware cost dramatically. The system memory bandwidth, on-chip memory size, and processing data throughput of each module all need to be optimized in an MVC encoder. Therefore, efficient hardware solutions for MVC architecture design are needed. In this article an overview of 3D video coding standards developments and design challenges of an MVC encoder are discussed. Then the algorithm and architecture optimization schemes are proposed. For the trade-off between system memory bandwidth and on-chip memory size, a cache-based prediction engine is proposed to ease both design challenges. Moreover, the hybrid open-close loop intra prediction scheme and the frame-parallel pipeline-doubled dual CABAC solve the throughput requirement problem. At the end of this article, based on all the proposed solutions, a prototype single-chip MVC encoder design with processing ability of 4096 × 2160 single-view to 1280 × 720 seven-view is presented.

Multiview video coding (MVC) plays an important role in a 3-D video system. In addition, the resolution of HDTV is increasing to present more vivid perception for users. To realize real-time processing of dozens of TOPS, VLSI solution is necessary. However, ultra high computational complexity, a large amount of external memory bandwidth and on-chip SRAM size, and complex MVC prediction structures are three main design challenges of implementation of MVC hardware architecture. In this paper, an MVC single-chip encoder is proposed for H.264/AVC Multiview High Profile and High Profile for 3-D and quad full high definition (QFHD) TV applications, respectively. The 4096 × 2160 p multiview video encoder chip is implemented on a 11.46 mm2 die with 90 nm CMOS technology. An eight-stage macroblock pipelined architecture with proposed system scheduling and cache-based prediction core supports real-time processing from one-view 4096 × 2160 p to seven-view 720 p videos. The 212 Mpixels/s throughput is 3.4 to 7.7 times higher than previous work. The 407 Mpixels/W power efficiency is achieved, and 94% on-chip SRAM size and 79% external memory bandwidth are saved by the proposed techniques.

The ability to predict and analyze the function of genetic circuits will enhance the design of autonomous, programmable, complex regulatory genetic structures. An abundance of modeling techniques has recently been developed to delineate simple genetic structures in terms of their constituents. Simple systems with characteristics of feedback inhibition, multi-stability, switching, and oscillatory expression have often been the focus. The present work is an attempt to improve existing deterministic models that fail to oblige to the crucial aspect of noise in genetic modeling. The objective of this work is to analyze, model, and simulate the protein populations in gene expression mechanisms by resorting to stochastic algorithms. The system involves two types of genes; the protein produced from the expression of one gene is capable of turning off the expression of the other gene. Rates of degradation of these proteins are assumed to be proportional to their concentrations. The master equation of this ‘genetic toggle switch’ is formulated using the probabilistic population balance around a particular state and by considering five mutually exclusive events. The efficacy of the present methodology is mainly attributable to the ability to derive the governing equations for the means, variances, and covariance of the random variables by the method of system-size expansion of the nonlinear master Equation. A less laborious approach based on Kurtz’s limit theorems for the derivation of the stochastic characteristics is also presented for comparison. Solving the resultant ordinary differential equations governing the means, variances, and covariance of the master equations simultaneously using the published data yield information concerning not only the means of the two populations of proteins but also the minimal uncertainties of the populations inherent in the expressions. It is demonstrated that systems with small populations are susceptible to large internal fluctuations (or uncertainties) in their population evolution. Large uncertainties are observed after the populations enter the proximity of the saddle node, which is likely to cause transition of system’s steady state from one to another. Independent Monte-Carlo simulation runs clearly demonstrates that the occurrence of such internal noise-induced transition.

Pyrolysis occurs in the initial stage of coal combustion where the volatile tar is generated. An important property of this volatile tar is its molecular-weight distribution. Coal tar contains varying sizes of monomers which are connected by linkages of varying strengths, thereby necessitating a stochastic approach. The present work has adopted the stochastic population balance of the system to derive the master equation for predicting the statistics of this molecular weight distribution of tar as functions of time. The tar produced during pyrolysis is assumed to undergo decomposition to low molecular weight compounds. Moreover, the system containing all tar molecules is lumped into a limited number of states, each representing a particular molecular weight range. The equations for the means, variances, and covariances of the random variables, each representing the number of tar molecules in an individual state in the system, have been derived from the master equation. The model has been compared with the experimental data obtained with both a heated-grid reactor and an entrained-flow reactor to recover the major parameters of the model, i.e. the transition and exit intensity functions. The transition intensity functions exhibit the temperature dependence of the Arrhenius type.

Isotopically labeled N15O was used to study the interaction of fuel nitrogen from coal with NO in a simulated reburning environment. Experiments were conducted in an alumina flow reactor operated at 1100°C with a reaction time estimated at 0.2 s. A North Dakota lignite and a Pittsburgh #8 bituminous coal were burned with a simulated flue gas containing 1000 ppm of N15O. Stoichiometric ratios ranged from 0.7 to 1.0. Species and isotope separation were accomplished using GC/MS. The ratio of labeled to unlabeled isotopes of each major nitrogen-containing species varied with stoichiometry, but not with coal type. Delayed nitrogen evolution from both coals was evident from the data. Data analysis showed that significant N2 production (i.e., greater than 50%) probably occurred through non-NO pathways. Little N15O was observed, indicating low conversion rates of intermediates to NO after significant nitrogen evolved from the coal.

A 5.877 TOPS/W Reconfigurable Smart-camera Stream Processor is implemented in 90nm CMOS technology. A reconfigurable hardware architecture with heterogeneous stream processing and subword-level parallelism is implemented to accelerate the vision processing for smart-camera applications. The area efficiency reaches 111.329 GOPS/mm2. The power efficiency and area efficiency are 4.5x to 33.0x and 3.8x to 74.2x better than the state-of-the-art works, respectively.

3DTV promises to become the mainstream of next-generation TV systems. Highresolution 3DTV provides users with a vivid watching experience. Moreover, free-viewpoint view synthesis (FVVS) extends the common two-view stereo 3D vision into virtual reality by generating unlimited views from any desired viewpoint. In the next-generation 3DTV systems, the set-top box (STB) SoC requires both a high-definition (HD) multiview video-coding (MVC) decoder to reconstruct the real camera-captured scenes and a free-viewpoint view synthesizer to generate the virtual scenes [1–2].

In recent years, 3D related applications, including 3D movie and 3DTV, are getting more and more attentions. In order to make the real-time 3D applications feasible, efficient multview video coding (MVC) scheme is desired. However, the system throughput requirement on a high definition (HD) MVC encoder is at least two times higher than the current highest throughput H.264/AVC encoder design. In order to meet the target HD MVC specifications, the system scheduling analysis for the HD MVC encoder is performed in this paper. By the 8-stage MB pipeline system architecture with view-parallel MB-interleaved system scheduling and other in-core computation optimizations, the proposed HD MVC encoder design provides about 339% to 1536% higher system throughput than the previous HD H.264/AVC encoder chips[4][5][6] and therefore the real-time HD MVC encoding can be achieved.

To observe the effect of tanshinone IIA (TS IIA) pretreatment on the expression of the inflammatory factor IL-1β and RelA mRNA in rats with focal cerebral ischemia.A total of 100 adult male SD rats were randomly divided into 6 groups, namely the model, ischemic preconditioning (IPC), TSIIA preconditioning, TSIIA treatment, sham-operated, and blank control groups. In the former 4 groups, rat models of focal cerebral ischemia were established with corresponding treatments. The expressions of IL-1β and RelA mRNA in each group were detected using RT-PCR.All the groups showed expressions of IL-1β and RelA mRNA with the exception of the blank control group. Compared to the model group, TSIIA preconditioning group, TSIIA treatment group, and IPC group all had significantly reduced expression of IL-1β and RelA mRNA (P0.05). The expressions were lower in IPC group than in TSIIA preconditioning group and TSIIA treatment group(P0.05), and no significant difference was found in the expressions between the latter two groups.The protective effect of pretreatment with TS IIA against cerebral ischemia is related to the reduction of IL-1β and RelA mRNA expressions.

Fractional motion estimation (FME) is widely used in video compression standards. In H.264/AVC, the precision of motion vector is down to quarter pixels to improve the coding efficiency. However, FME occupies over 45% of the computation complexity in an H.264 encoder and this high complexity limits the processing capability. In this paper, a single-iteration full search FME is proposed. By the algorithm and architecture co-optimization, the bandwidth to the frame buffer is reduced by 31%. Furthermore, 82% of circuit area for the Hadamard transformation and subtraction are saved from the direct implementation. Compared with prior arts, the proposed design supports 3.39 × higher throughput with only 0.02 dB PSNR drop. Thus, the specification of 4096 × 2160 quad full high definition H.264/AVC FME processing can be achieved.

To provide more vivid perception, more and more advanced features, like the 4k×2k resolution and the multiview functionality, are emerging for TV. For a multiview video coding (MVC) encoder, motion and disparity estimation (ME/DE) take at least half the hardware requirement. To solve these challenges, a cache-based integer ME/DE algorithm is proposed. With a cache memory as the search window buffer, a predictor-centered ME/DE algorithm is presented. The search range can be reduced to ±16 pixels with less than 0.1dB quality drop compared with full search algorithm. Based on this algorithm, an integer ME/DE chip design is realized. It can reduce 82% on-chip SRAM and 39% system bandwidth. Moreover, the search candidate requirement is also reduced by 79%. As the result, an ME/DE chip design for 4k×2k quad-HD H.264 and HDTV MVC is implemented.

Multiview video coding (MVC) is getting more and more attention in recent years because of the realistic perception it can bring. However, the current H.264-based coding scheme cannot get enough coding gain in the rate-distortion (R-D) performance. Furthermore, the view synthesis and random access between views are also design challenges. In this paper, a multiview hybrid coding system with texture-depth synthesis is proposed. By sharing the prediction information between texture and depth maps, the depth map can be reconstructed with reduced bitrate overhead. Then, after using matrix-based warping and adaptive disparity compensation, the R-D performance of the proposed system can be about 2 to 4 dB higher than the current MVC coding scheme at low bitrate range.

Multiview video coding (MVC) plays a critical role in 3D-TV systems. However, MVC require much more memory bandwidth and computational complexity relative to mono-view video coding. Therefore, an efficient prediction scheme is necessary for computation reduction. In this paper, a new fast prediction algorithm, computation-free motion estimation (ME) with inter-view mode decision, is proposed. By utilizing disparity estimation to find corresponding blocks between different views, the coding information, such as modes and motion vectors, can be effectively reused from the coded view channel. Therefore, the computation for ME can be almost totally neglected in most view channels. Besides, the proposed algorithm also provides the computation scalability. Experimental results show that compared with the full search block matching algorithm (FSBMA), the proposed algorithm not only save 61-72% computation with near-FSBMA quality, but save almost 100% computation with a little quality drop of 0.23-0.36 dB. Thus, computation-free ME is achieved.

Multiview video coding (MVC) systems require much more bandwidth and computational complexity relative to mono-view video systems. Thus, when designing a VLSI architecture for MVC systems, the hardware resource allocation is a critical issue. In this paper, we propose a new system bandwidth analysis scheme for various and complicated MVC structures. The precedence constraint in the graph theory is adopted for deriving the processing order of frames in a MVC system. In addition, current block centric scheduling (CBCS) and search window centric scheduling (SWCS) are proposed for MVC bandwidth analysis. By adopting data reuse schemes, several design points are explored with the aid of the proposed analysis scheme. The suitable hardware resource allocation can be easily determined.

Luminance and chrominance correction (LCC) is important in multi-view video coding (MVC) because it provides better rate-distortion performance when encoding video sequences captured by ill-calibrated multi-view cameras. This paper presents a robust and fast LCC algorithm based on motion compensated linear regression which reuses the motion information from the encoder. We adopt the linear weighted prediction model in H.264/AVC as our LCC model. In our experiments, the proposed LCC algorithm outperforms basic histogram matching method up to 0.4dB with only few computational overhead and zero external memory bandwidth. So, the dataflow of this method is suitable for low bandwidth/low power VLSI design for future multi-view applications.

Recent studies of heterogeneous reburning, i.e., reburning involving a coal-derived char, have elucidated its variables, kinetics and mechanisms that are valuable to the development of a highly efficient reburning process. Young lignite chars contain catalysts that not only reduce NO, but they also reduce HCN that is an important intermediate that recycles to NO in the burnout zone. Gaseous CO scavenges the surface oxides that are formed during NO reduction, regenerating the active sites on the char surface. Based on this mechanistic information, cost-effective mixed fuels containing these multiple features has been designed and tested in a simulated reburning apparatus. Remarkably high reduction of NO and HCN has been observed and it is anticipated that mixed fuel will remove 85% of NO in a three-stage reburning process.

Reburning is an emerging three-stage combustion technology designed for the reduction of NO by introducing a small amount of reburning fuel above the primary flame where the majority of NO is chemically reduced to nitrogen. While coal, in general, has not been considered an effective reburning fuel, research at the University of Mississippi suggested that lignite has a reburning efficiency even higher than that of methane. Furthermore, heterogeneous mechanisms are more important than homogeneous mechanisms for char/NO reaction. The objectives of this research are to investigate: (1) implications of pore structure analysis, (2) parameters governing heterogeneous reactions, and (3) estimation of rates of NO reduction and mass transfer limitations. Experiments have been performed in a flow reactor with a simulated fuel gas at a stoichiometric ratio (SR) 1.1. Reburning fuels in this study include chars derived from Pittsburgh No.8 bituminous coal and Mississippi lignite. Chars were produced in N{sub 2} by suspending a sample basket in a tube furnace. Pore structure analyses include BET-N{sub 2}, BET-CO{sub 2}, and DR-CO{sub 2} surface pore size distribution, micropore volume, total pore volume, and average pore radius. These studies suggest that neither BET-N{sub 2} nor DR- CO{sub 2} surface area is a normalization factormore » of chars of different origin. Reaction with NO leads to closures of pores, which may be contributed by formation of surface complexes.« less

The four major tasks conducted during this quarter include: (1) extensive investigation in pore structures of chars before and after reactions with NO , CO,, and 02, (2) effects of pyrolysis time on char reactivities, (3) estimations of rates of NO reduction and mass transfer limitations, and, (4) char reactivities at low feed NO concentrations. Pore structure analyses include BET-N{sub 2}, BET-CO{sub 2}, and DR-CO{sub 2} surface areas, pore size distribution, micropore volume, total pore volume, and average pore radius. These studies suggest that neither BET-N{sub 2} nor DR-CO{sub 2} surface area is a normalization factor of chars of different origin. Parameter study reveals that the effectiveness of heterogeneous reburning strongly depends on variables in three areas: (1) the origin of char, (2) char devolatilization temperature and time, and, (3) the competitions of NO with C0{sub 2} and 02 for the active sites on the char surface. The studies on pore structure and on parameter screening signify the importance of transient kinetics (TK) and temperature programmed desorption (TPD) in the future research. These two techniques all lead to the direct measurements of both stable and reactive surface oxygen complexes, reactive surface area, and the Langmuir-Hinshelwood model which has both importance to both fundamental understanding of reaction mechanisms and to industrial practice. Estimation of rate of NO reduction has been established to include the conversions in the nonisothermal and isothermal regions of the flow reactor, and internal mass transfer limitations. Solving a set of equations simultaneously with MathCad gives frequency factor, activation energy, Thiele modulus, and effectiveness factor.

During this quarter, we have investigated rates and product compositions of NO reduction on chars in gases. N{sub 2} and CO{sub 2} internal surface areas of chars, selected from runs of various pyrolysis and reaction conditions have been measured to assist in interpreting the experimental results. Implications of Langmuir- Hinshelwood mechanisms and mass transfer limitations were examined. Oxidants suppress NO reduction on bituminous coal char more than on lignite char. Observations suggest that NO adsorption and desorption of stable surface oxygen complexes are potentially important rate- limiting steps and may be catalyzed by mineral matter during reburning with lignite char. Relative inert nature of lignite char to CO{sub 2} presence may have potential value in use of fuel system involving both solid and volatile fuels. Lignite char produced at 950 C and zero holding time has higher reactivity than that produced at 1100 C and 5 min holding time. Bituminous coal chars produced at these two conditions, however, have similar reactivity with NO. Internal surface areas of both type chars vary with pyrolysis conditions and gas composition in the subsequent reaction. When oxidants are introduced in the feed, internal surface areas of these two chars vary in opposite directions.

The investigation of this quarter focuses on the rates of NO reactions with chars in various gaseous environments. The results have revealed significant insights into the NO reduction mechanisms on char surface, particularly when the oxidants, O{sub 2} and CO{sub 2}, are introduced into the feed. Indeed, evidences suggest that the formation of stable oxygen complexes is the major cause of differences in NO reactivity on chars of different origins. The oxidants retard the reactivity of char derived fro the bituminous coal more seriously than they affect the char derived from lignite. Furthermore, additions of these oxidants into the reacting stream produce additional yields of CO and CO{sub 2} during NO reaction with lignite char, suggesting gasification of carbon from lignite char. No excess CO and CO{sub 2} were observed when the bituminous coal char was used. These yields of CO and CO{sub 2} also imply that desorption of stable surface oxygen complex is a rate-limiting step which may be catalyzed by the mineral matters during reactions involving lignite char. Surface area evaluated by CO{sub 2} and Dubinin-Radushkevich (D-R) equation is not a normalization factor of char reactivity during reburning. In the absence of oxidants, the bituminous coal char shows drastic increase in activation energy at about 950 {degrees}C indicating transition of desorption to adsorption controlled mechanisms. When CO{sub 2} is introduced, the transition temperature increases. When oxygen is also added, no such transition is observed up to 1100 {degrees}C. Lignite char reactivity increases smoothly over the temperature range 800 to 1100 {degrees}C. It is also observed that char reactivity decreases with increasing pyrolysis temperature which may be caused by closure of pores due to graphitization. The rate of NO reduction on the Pittsburgh {number_sign}8 coal char is then in good accord with that of a West Virginia coal char reported by De Soete (1980).

The progress in this quarter includes four parts. In the first segment, the implications of our data reported in the List quarter are discussed further. BET N{sub 2} surface area does not seems to be the only contributing factor to the remarkable activity of lignite char during reburning, and chars of different origins probably have different controlling steps in the overall surface reaction mechanisms. Unlike NO reduction in the gas phase, oxygen inhibits the heterogeneous mechanisms. The second part of this report justifies the use of our laminar flow reactor system for the measurement of reaction rate. Dispersion model is used in the analysis. An expression relating the rate constant with the experimentally obtainable NO conversion for our flow reactor have been derived. Rates of NO/char reaction for six series of experiments have been measured over the temperature range 800 to 1100{degrees}C. These six series of experiments have been conducted with two different chars, one bituminous coal char and one lignite char, and three different levels of feed NO concentrations, 200, 400 and 1000 ppm. Results from the comparison of char activities suggest that, in the absence of O{sub 2} and CO{sub 2}, the origin of char is not a significant factor for NO reduction. The CO/CO{sub 2} ratio in the products is higher than one under all test conditions, but the ratio increases with increasing feed NO concentrations. Recoveries of oxygen form the lignite char at temperatures above 1050{degrees}C is higher than 1 indicating gasification of organic oxygen in the char. Surface areas of selected chars after devolatilization and after reburning have been analyzed by BET in N{sub 2}. Results indicated char surface area changes after reburning, which is caused either by the higher temperature of reburning or by surface reaction.

This program addresses the mechanisms of NO reduction in pulverized coal flames using reburning. Using both thermodynamic and kinetic simulation combined with both pilot and bench scale experimental work, we propose to better define the conditions that lead to the destruction of NO, without the concomitant increase in other nitrogeneous pollutants. Specifically, the interactions between NO and hydrocarbon constituents in the fuel, and the fate of fuel nitrogen are the focal points of this research. Isotope doped 15 NO is used for tracing the reaction pathways.

This program addresses the mechanisms of NO reduction in pulverized coal flames using reburning. Using both thermodynamic and kinetic simulation combined with both pilot and bench scale experimental work, we propose to better define the conditions that lead to the destruction of NO, without the concomitant increase in other nitrogeneous pollutants. Specifically, the interactions between NO and hydrocarbon constituents in the fuel, and the fate of fuel nitrogen are the focal points of this research. Isotope doped 15 NO is used for tracing the reaction pathways.

The study of stoichiometric constraints under equilibrium conditions provides us with the following information related to reburning as a NO reduction technology: (1) The stoichiometry of air to fuel is the most important stoichiometry of air to fuel is the most important stoichiometric variable for reburning; (2) based on equivalent energy production, the comparative reduction efficiencies of the reburning fuels follow the trend: methane > ethane, ammonia > butane > aromatics, coal > CO; (3) the nitrogen in burning coals causes increases in equilibrium NO; (4) equilibrium TFN is not very sensitive in inlet NO concentration; (5) the heat carried by the flue gas in reburning could push the NO reduction toward equilibrium. If so, reburning has a strong correlation with air staging with air preheat. Further experimental verification is required.

During this quarter we continued to develop improved techniques of using aluminum diaphragms in the chemical shock tube and of analyzing reaction products. Tests with wide ranges of shock pressures have provided a set of baseline data for the proper selection of Al diaphgrams thickness. Our pioneer work on the analysis of trace amounts of NO, NO/sub 2/, NH/sub 3/, and HCN with gas chromatography/mass spectrometry were concentrated on column selection, and the use of a cold trap at the GC inlet. The down-fired furnace was completed, and initial confirmatory testing began. Several new sections of refractory had to be built because of damage sustained in transit from Kansas State University to LSU. Additionally, the on-line analyzers for O/sub 2/, CO, CO/sub 2/, and NO/sub x/ had to be calibrated and tested under suitable furnace conditions. Finally, the furnace was successfully fired with natural gas/air flames doped with ammonia to assess the potential performance of the sampling system and analyzer under conditions comparable to those to be employed during the second year of the program. 2 refs., 5 figs., 1 tab.

The study of stoichiometric constraints under equilibrium conditions provides us with the following information related to reburning as a NO reduction technology: (1) The stoichiometry of air to fuel is the most important stoichiometry of air to fuel is the most important stoichiometric variable for reburning; (2) based on equivalent energy production, the comparative reduction efficiencies of the reburning fuels follow the trend: methane > ethane, ammonia > butane > aromatics, coal > CO; (3) the nitrogen in burning coals causes increases in equilibrium NO; (4) equilibrium TFN is not very sensitive in inlet NO concentration; (5) the heat carried by the flue gas in reburning could push the NO reduction toward equilibrium. If so, reburning has a strong correlation with air staging with air preheat. Further experimental verification is required.