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71.
72.
In a machine translation system, word sense disambiguation has an essential role in the proper translation of words when the target word can be translated differently depending on the context. Previous research on sense identification has mostly focused on adjacent words as context information. Therefore, in the case of nominal compounds, sense tagging of unit nouns mainly depended on other nouns surrounding the target word. In this paper, we present a practical method for the sense tagging of Korean unit nouns in a nominal compound. To overcome the weakness of traditional methods regarding the data sparseness problem, the proposed method adopts complement‐predicate relation knowledge that was constructed for machine translation systems. Our method is based on a sentential form recovery technique, which recognizes grammatical relationships between unit nouns. This technique makes use of the characteristics of Korean predicative nouns. To show that our method is effective on text in general domains, the experiments were performed on a test set randomly extracted from article titles in various newspaper sections.  相似文献   
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74.
Distribution of interface states at the emitter–base heterojunctions in heterostructure bipolar transistors (HBTs) is characterized by using current–voltage characteristics using sub-bandgap photonic excitation. Sub-bandgap photonic source with a photon energy Eph which is less than the energy bandgap Eg (Eg,GaAs = 1.42, Eg,AlGaAs = 1.76 eV) of emitter, base, and collector of HBTs, is employed for exclusive excitation of carriers only from the interface states in the photo-responsive energy range at emitter–base heterointerface. The proposed method is applied to an Al0.3Ga0.7As/GaAs HBT (AE = WE × LE = 250 × 100 μm2) with Eph = 0.943 eV and Popt = 3 mW. Extracted interface trap density Dit was observed to be Dit,max  4.2 × 1012 eV−1 cm−2 at emitter–base heterointerface.  相似文献   
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76.
Seong  Ju-Hyeon  Seo  Dong-Hoan 《Wireless Networks》2019,25(6):3019-3027
Wireless Networks - The Wi-Fi fingerprint, which can be used on existing wireless networks, is one of the main indoor positioning techniques that utilizes the received signal strength (RSS). In...  相似文献   
77.
We investigate the effects of ZnO annealing temperature (TA) on the performance of inverted polymer solar cells with ZnO electron-selective layers deposited by spin coating aqueous solutions of an ammine-hydroxo zinc complex. The inverted solar cells based on poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester with TA as low as 80 °C exhibit power-conversion efficiencies of 3.6%, which is equal to those of devices with higher TA. Characterizations of the ZnO films using X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, grazing incidence wide-angle X-ray scattering, and optical transmittance measurements show that the abrupt improvement of device performance from TA = 60 to 80 °C is due to the improvement of energy-level alignment arising from the increases in the relative amount and the crystallinity of ZnO.  相似文献   
78.
Ceramic–polymer composites are of interest for designing enhanced and unique properties. However, the processing temperature windows of sintering ceramics are much higher than that of compaction, extrusion, or sintering of polymers, and thus traditionally there has been an inability to cosinter ceramic–polymer composites in a single step with high amounts of ceramics. The cold sintering process is a low‐temperature sintering technology recently developed for ceramics and ceramic‐based composites. A wide variety of ceramic materials have now been demonstrated to be densified under the cold sintering process and therefore can be all cosintered with polymers from room temperature to 300 °C. Here, the status, understanding, and application of cold cosintering, with different examples of ceramics and polymers, are discussed. One has to note that these types of cold sintering processes are yet new, and a full understanding will only emerge after more ceramic–polymer examples emerge and different research groups build upon these early observations. The general processing, property designs, and an outlook on cold sintering composites are outlined. Ultimately, the cold sintering process could open up a new multimaterial design space and impact the field of ceramic–polymer composites.  相似文献   
79.
A number of government-sponsored large-scale R&D projects in the telecommunications sector have been carried out in Korea. Among them is the time division exchange (TDX) project that lasted for more than 15 years. The project has two characteristics: the commercialization of government-sponsored R&D and the commercialization of R&D with multiple development cycles. This paper describes these characteristics of the project from various viewpoints: product development strategy, the role of each organization, success factors of each product, the classification of commercial products by commercialization model, and technology transfer strategies encouraging participation of manufacturing firms. We conclude with several recommendations  相似文献   
80.
The Ni-rich precursor powders with spherical shape and filled morphologies were prepared by spray pyrolysis from the spray solution with citric acid, ethylene glycol and a drying control chemical additive. The precursor powders with controlled morphologies formed the LiNi0.8Co0.15Mn0.05O2 cathode powders with spherical shape and fine size by solid-state reaction with lithium hydroxide. However, the cathode powders prepared from the spray solution without additives had irregular morphologies and were large in size. The precursor powders with hollow and porous morphologies formed cathode powders with irregular and aggregated morphologies. The composition ratios of the nickel, cobalt and manganese components were maintained in the as-prepared, precursor and cathode powders. The initial discharge capacity of the LiNi0.8Co0.15Mn0.05O2 cathode powders with spherical shape and fine size tested at a temperature of 55 °C under a constant current density of 0.5 C was 215 mAh g−1. The discharge capacity of the LiNi0.8Co0.15Mn0.05O2 cathode powders decreased to 81% of the initial value after 30 cycles.  相似文献   
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