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Finite state translation systems and parallel multiple context-free grammars
Full text linkFinite state translation systems (fsts') are a widely studied computational model in the area of tree automata theory. In this paper, the string generating capacities of fsts' and their subclasses are studied. First, it is shown that the class of string languages generated by deterministic fsts' equals to that of parallel multiple context-free grammars, which are an extension of context-free grammars. As a corollary, it can be concluded that the recognition problem for a deterministic fsts is solvable in O(n e+1)-time, where n is the length of an input word and e is a constant called the degree of the deterministic fsts'. In contrast to the latter fact, it is also shown that nondeterministic monadic fsts' with state-bound 2 can generate an NP-complete language.technical repor
Light Scattering Study on the Structure of Pure Polystyrene
Full text linkAn unusual temperature dependence of light scattering properties by pure polystyrene (PS) was observed in the temperature range of 30?170°C: the V′v and Vviso′ intensities minimized near Tg, and the H′v intensity changed with measuring temperatures. These phenomena can be explained by “the scrambling effects of incident and scattered light” during transmission through the sample, as previously pointed out for PS glass by Claiborne and Crist. The PS sample used was prepared by a very careful procedure in which the evaporable monomer, initiator, and chain transfer agent were distilled in a closed vacuum system and in situ polymerization was carried out above Tg. The corrected Vviso intensity for PS glass was favorably compared with the values calculated from the thermal density fluctuation, indicating that PS glass was in a frozen state near Tg. The corrected Hv intensity for PS glass was nearly equal to the heretofore calculated value, assuming a randomly oriented anisotropic liquid for PS. Our experimental results showed no evidence for an ordered structure in pure PS glass, as is found in pure poly(methyl methacrylate) glass, but PS rubber has a partially oriented state.journal articl
Light Scattering Study on the Structure of Pure Poly(methyl methacrylate)
Full text linkThe polarized and depolarized components of light scattering by pure poly-(methyl methacrylate) (PMMA) were measured as a function of temperature above and below Tg. The PMMA sample used was prepared by a very careful procedure in which the evaporable monomer, initiator, and chain transfer agent were distilled in a closed vacuum system and in-situ polymerization was carried out above Tg. The measured Vviso intensities were favorably compared with the values calculated from thermal density fluctuation in the temperature range from 20 to 140°C. The measured intrinsic Hv intensity was fairly close to the value calculated assuming a randomly oriented anisotropic liquid for PMMA. Our experiment showed no evidence for an ordered structure in pure PMMA glass, as is found in pure polystyrene glass.journal articl
Low-loss polystyrene core-optical fibers
Full text linkLow‐loss plastic optical fibers (POF) have been prepared with the attenuation loss of 114 dB/km at the wavelength of 670 nm employing polystylene core and ethylene‐vinylacetate copolymer cladding. The POF can allow the use for short‐distance optical signal transmission. The theoretical loss limit of polystylene core POF is calculated to be 70 dB/km at 670 nm.journal articl
A Fast Simulation Method Using SPH and Wavelet for Turbulent Flow
Full text linkThis paper presents a fast simulation method for turbulent flow which uses a particle method and wavelet analysis. To simulate fluid flow, the method uses smoothed particle hydrodynamics (SPH), which discretizes the fluid into a collection of particles, and detects regions where turbulent flow will occur by using wavelet analysis without a spatial grid. By taking the curl of wavelet noise, the turbulent flow is then appended as a divergence-free turbulence velocity field. Additionally, by using a particle splitting, which characterize the vortex features of turbulence, a sub-particle-scale representation of turbulent flow is proposed. Implementing almost all processes on a graphics processing unit (GPU), simulations are performed in near real timeconference pape
Complaints with Target Scope Identification on Social Media
No full textA complaint is uttered when reality fails to meet one’s expectations. Research on complaints, which contributes to our understanding of basic human behavior, has been conducted in the fields of psychology, linguistics, and marketing. Although several approaches have been implemented to the study of complaints, studies have yet focused on a target scope of complaints. Examination of a target scope of complaints is crusial because the functions of complaints, such as evocation of emotion, use of grammar, and intention, are different depending on the target scope. We first tackle the construction and release of a complaint dataset of 6,418 tweets by annotating Japanese texts collected from Twitter with labels of the target scope. Our dataset is available at https://github.com/sociocom/JaGUCHI. We then benchmark the annotated dataset with several machine learning baselines and obtain the best performance of 90.4 F1-score in detecting whether a text was a complaint or not, and a micro-F1 score of 72.2 in identifying the target scope label. Finally, we conducted case studies using our model to demonstrate that identifying a target scope of complaints is useful for sociological analysis.journal articl
