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1.
A new excimer laser annealing (ELA) process that uses a floating amorphous-Silicon (a-Si) thin film with a multichannel structure is proposed for high-performance poly-Si thin-film transistors (TFTs). The proposed ELA method produces two-dimensional (2-D) grain growth, which can result in a high-quality grain structure. The dual-gate structure was employed to eliminate the grain boundaries perpendicular to the current flow in the channel. A multichannel structure was adapted in order to arrange the grain boundary to be parallel to the current flow. The proposed poly-Si TFT exhibits high-performance electrical characteristics, which are a high mobility of 504 cm/sup 2//Vsec and a low subthreshold slope of 0.337 V/dec. 相似文献
2.
Shinsook Yoon Mi-Kyoung Kim In-Young Lee Mikyung Yun Jeong E. Nam Shin 《Journal of Industrial and Engineering Chemistry》2008,14(6):759-764
We have developed a mutant strain derived from Agrobacterium sp. ATCC 31750, which produces a water-soluble polysaccharide having potential utility to the food, feed, pharmaceutical and cosmetic industries. A high concentration of product (15 g/L) is obtained by 48 h cultivation of the mutant strain under optimized fermentation conditions. The water-soluble polysaccharide obtained from cultures of the mutant strain beta82 has Glc:Man:Gal in approximate molar ratios of 5.8:6.7:1.0. The molecular weight of the polysaccharide was determined to be approximately 1000 kDa by HPSEC analysis. Linkage analysis contained 3-Glcp, 3-Manp, terminal Glcp and terminal Manp, as well as a small proportion of 3- and 3,4-Galp, and 4,6-Manp residues. Based on analyses using FT-IR and 13C NMR spectrometers, most glycosidic bonds joining these sugar residues are of the α-type, and acetyl groups are apparently attached to the polymer chain at random. 相似文献
3.
Deactivation of copper-ion-exchanged hydrogen-mordenite-type zeolite catalyst by SO2 for NO reduction by NH3 was examined in a fixed-bed flow reactor. The deactivation of the catalyst was strongly dependent on reaction temperature. At high reaction temperatures over 300°C, the catalyst did not lose its initial activity up to 50 h of operation, regardless of SO2 feed concentration from 500 to 20,000 ppm. However, at low reaction temperatures near 250°C, apparent deactivation did occur. Changes in the physicochemical properties such as surface area and sulfur content of deactivated catalyst well correlated with catalyst activity, depending upon reaction temperatures. The deactivation was due to pore blocking and/or filling by deactivating agents, which plugged and/or filled the pores of catalyst. The deactivating agents deposited on the catalyst surface were presumed to be (NH4)2SO4 and/or (NH4)HSO4 from the results of TGA and ion-chromatography measurement. 相似文献
4.
Thanh Hai Nguyen Phan Khanh Linh Tran Van An Dinh Duy Thanh Tran Nam Hoon Kim Joong Hee Lee 《Advanced functional materials》2023,33(7):2210101
Development of multifunctional electrocatalysts with high efficiency and stability is of great interest in recent energy conversion technologies. Herein, a novel heteroelectrocatalyst of molecular iron complex (FeMC)-carbide MXene (Mo2TiC2Tx) uniformly embedded in a 3D graphene-based hierarchical network (GrH) is rationally designed. The coexistence of FeMC and MXene with their unique interactions triggers optimum electronic properties, rich multiple active sites, and favorite free adsorption energy for excellent trifunctional catalytic activities. Meanwhile, the highly porous GrH effectively promotes a multichannel architecture for charge transfer and gas/ion diffusion to improve stability. Therefore, the FeMC–MXene/GrH results in superb performances towards oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline medium. The practical tests indicate that Zn/Al–air batteries derived from FeMC–MXene/GrH cathodic electrodes produce high power densities of 165.6 and 172.7 mW cm−2, respectively. Impressively, the liquid-state Zn–air battery delivers excellent cycling stability of over 1100 h. In addition, the alkaline water electrolyzer induces a low cell voltage of 1.55 V at 10 mA cm−2 and 1.86 V at 0.4 A cm−2 in 30 wt.% KOH at 80 °C, surpassing recent reports. The achievements suggest an exciting multifunctional electrocatalyst for electrochemical energy applications. 相似文献
5.
Autonomous topological modeling of a home environment and topological localization using a sonar grid map 总被引:1,自引:0,他引:1
This paper presents a method of autonomous topological modeling and localization in a home environment using only low-cost
sonar sensors. The topological model is extracted from a grid map using cell decomposition and normalized graph cut. The autonomous
topological modeling involves the incremental extraction of a subregion without predefining the number of subregions. A method
of topological localization based on this topological model is proposed wherein a current local grid map is compared with
the original grid map. The localization is accomplished by obtaining a node probability from a relative motion model and rotational
invariant grid-map matching. The proposed method extracts a well-structured topological model of the environment, and the
localization provides reliable node probability even when presented with sparse and uncertain sonar data. Experimental results
demonstrate the performance of the proposed topological modeling and localization in a real home environment. 相似文献
6.
The purpose of this study was to investigate cortical interaction between brain regions in people with and without severe motor disability during brain-computer interface (BCI) operation through coherence analysis. Eighteen subjects, including six patients with cerebral palsy (CP) and three patients with amyotrophic lateral sclerosis (ALS), participated. The results showed (1) the existence of BCI performance difference caused by severe motor disability; (2) different coherence patterns between participants with and without severe motor disability during BCI operation and (3) effects of motor disability on cortical connections varying in the brain regions for the different frequency bands, indicating reduced cortical differentiation and specialisation. Participants with severe neuromuscular impairments, as compared with the able-bodied group, recruited more cortical regions to compensate for the difficulties caused by their motor disability, reflecting a less efficient operating strategy for the BCI task. This study demonstrated that coherence analysis can be applied to examine the ways cortical networks cooperate with each other during BCI tasks. PRACTITIONER SUMMARY: Few studies have investigated the electrophysiological underpinnings of differences in BCI performance. This study contributes by assessing neuronal synchrony among brain regions. Our findings revealed that severe motor disability causes more cortical areas to be recruited to perform the BCI task, indicating reduced cortical differentiation and specialisation. 相似文献
7.
The state equivalence condition to the nonlinear observer form is stated in terms of the exactness of one-form. Using the definition of the approximate closedness, we relax the equivalence condition, thereby obtaining a necessary and sufficient condition for the approximate observer error linearizability. This approximate observer theory extends the realm of applications. Another great advantage of this approximation method is that the coordinate transformation is directly obtainable as vectors of polynomials, while it is, in general, not possible with the existing method, 相似文献
8.
A study on a generalized parametric interpolator with real-time jerk-limited acceleration 总被引:9,自引:0,他引:9
Sung-Ho Nam 《Computer aided design》2004,36(1):27-36
The impossibility of exact arc length computation for ‘standard’ parametric curves such as Bézier/B-spline curves makes it difficult to generate a feedrate profile with desired accelerations in real-time. This paper presents a new recursive trajectory generation method that estimates an admissible path increment and determines the initiation of the final deceleration stage according to the distance left to travel estimated at every sampling time, resulting in exact feedrate trajectory generation through jerk-limited acceleration profiles for the parametric curves. The proposed approach allows the feedrate profile to be dynamically adjusted according to geometrical path constraints for the curved path. The simulation result has been also provided to illustrate the generation of smooth feedrate profile encompassing a sequence of mixed NC blocks including traditional linear and circular blocks. 相似文献
9.
Nam Cong-Nhat Huynh Tze-Ta Huang Chi Thi-Kim Nguyen Fang-Kuei Lin 《International journal of molecular sciences》2022,23(12)
Cancer-associated fibroblasts (CAFs) and partial epithelial–mesenchymal transition (p-EMT) tumor cells are closed together and contribute to the tumor progression of oral squamous cell carcinoma (OSCC). In the present study, we deeply analyzed and integrated OSCC single-cell RNA sequencing datasets to define OSCC CAFs and p-EMT subpopulations. We highlighted the cell–cell interaction network of CAFs and p-EMT tumor cells and suggested biomarkers for the diagnosis and prognosis of OSCC during the metastasis condition. The analysis discovered four subtypes of CAFs: one p-EMT tumor cell population, and cycling tumor cells as well as TNFSF12-TNFRSF25/TNFRSF12A interactions between CAFs and p-EMT tumor cells during tumor metastasis. This suggests the prediction of therapeutically targetable checkpoint receptor–ligand interactions between CAFs and p-EMT tumor cells in OSCC regarding the metastasis status. 相似文献
10.