Unsupervised Text Embedding Space Generation Using Generative Adversarial Networks for Text Synthesis

Generative Adversarial Networks (GAN) is a model for data synthesis, which creates plausible data through the competition of generator and discriminator. Although GAN application to image synthesis is extensively studied, it has inherent limitations to natural language generation. Because natural language is composed of discrete tokens, a generator has difficulty updating its gradient through backpropagation; therefore, most text-GAN studies generate sentences starting with a random token based on a reward system. Thus, the generators of previous studies are pre-trained in an autoregressive way before adversarial training, causing data memorization that synthesized sentences reproduce the training data. In this paper, we synthesize sentences using a framework similar to the original GAN. More specifically, we propose Text Embedding Space Generative Adversarial Networks (TESGAN) which generate continuous text embedding spaces instead of discrete tokens to solve the gradient backpropagation problem. Furthermore, TESGAN conducts unsupervised learning which does not directly refer to the text of the training data to overcome the data memorization issue. By adopting this novel method, TESGAN can synthesize new sentences, showing the potential of unsupervised learning for text synthesis. We expect to see extended research combining Large Language Models with a new perspective of viewing text as an continuous space

Development of real-time investigation technique for nonpoint pollution source distribution using programming interface

Currently both central and local governments that are aware of the importance of conserving rivers, are making continuous efforts to solve the problem of non-point pollution sources (NPS) flowing into rivers. This study established a reactive web service app with a mobile application, to accommodate the need for systematic and scientific investigation and management of NPS. The developed investigation and management techniques incorporate all the PC-based administrative features, thereby improving development efficiency. A prototype of mobile GIS platform for a survey, inspection, and input was proposed, in which data related to pollution source locations and attributes can be effectively collected, stored, updated, and adjusted. To demonstrate, we conducted a quantitative analysis of river pollution source using GPS and GIS to show further details of the framework, which provides geographic information required to develop management technique of NPS flowing into rivers and related parameters in the form of a map. Furthermore, based on the interpolated maps and various environmental factors, the prediction of NPS as well as other parameters can be done. The research will not only improve the efficiency of investigation and management of NPS but also contribute to establishing a management policy, which covers quick decision-making and reaction to inflow accidents

Evaluation of tensile properties using instrumented indentation technique for small scale testing

The Instrumented indentation technique (IIT) is a useful tool for estimating various mechanical properties such as tensile properties, fracture toughness, and residual stress by analyzing the load and depth curve. Unlike conventional test such as tensile test, CTOD, since IIT makes an indent with rigid indenter and measures load and depth continuously, it requires only a localized area and small area on the target material. IIT also has merits of simple specimen preparation and experimental procedure in terms of time and cost. Also, it can be applied to in-field structures nondestructively. In this study, we introduce a method for evaluating tensile properties, primary yield strength and tensile strength using representative stress-strain beneath the rigid spherical indenter through numerous investigations of instrumented indentation curves. Analytic models and procedures for estimating the mechanical characterization of materials using IIT are proposed. The representative stress-strain method directly correlates indentation stress and strain beneath indenter to true stress and strain of the tensile test by taking into account the plastic constraint effect. The experimental results from IIT were verified by comparing results from the uniaxial tensile test. In particular, the applications of IIT in small scale and localized area of materials are presented. Reference 1) D. Tabor: Hardness of metal, (first ed. Clarendon Press, New York, 1951) 2) W.C. Oliver and G.M. Pharr, J. Mater, Res, Vol. 7, (1992), p. 1564 3) S.-K. Kang, Y.-C. Kim, K.-H. Kim, J.-Y. Kim and D. Kwon, Int. J. Plast. 49, 1 (2013

Investigation of the physicochemical features and mixing of East/Japan Sea Intermediate Water: An isopycnic analysis approach

We present spatial distributions of the mixing ratio and properties of the East/Japan Sea Intermediate Water (ESIW) at its core density layer (σθ = 27.2–27.3) based on high-quality hydrographic data observed in the East/Japan Sea (EJS) during summer 1999. ESIW is defined as a source water type showing minimum salinity and maximum dissolved oxygen concentration. ESIW plays an important role in supplying dissolved oxygen and transporting anthropogenic carbon into the intermediate/deep layers in EJS. Studying the ESIW formation and distribution processes may provide insights on EJS\u27s shallow- to mid-depth thermohaline circulation and recent ocean changes. Here, we combine the previously estimated mixing ratio of ESIW, based on Optimum Multi-Parameter (OMP) analysis, and its physicochemical properties, such as pressure, dissolved oxygen, and phosphate, interpolated onto several isopycnic surfaces (σθ = 27.20, 27.25, and 27.30). The physicochemical properties of ESIW show steep north-south gradients across the subpolar front at 40–41°N. Higher dissolved oxygen concentrations (≥335 μmol kg–1) of ESIW are found in the western Japan Basin particularly off the Primorye coast, indicating a potential source region. The spatial and depth distributions of apparent oxygen utilization (AOU) on the ESIW isopycnic surfaces indicate that the subduction of ESIW occurs at 131–133°E (Ulleung Basin) across the subpolar front to the south. The density layer of ESIW shoals near the Korean coast in the Ulleung Basin, implying a potential link to coastal upwelling. The relative age of ESIW at its core layer is estimated from the oxygen utilization rate and AOU. The correlation between the pCFC12 and relative ages, and AOU estimated at 90% surface water oxygen saturation condition suggests a decadal-scale ventilation of ESIW (≤24 years). Younger waters at the ESIW coexist with the high-salinity intermediate water at the same density layer in the eastern Japan Basin. Our analysis suggests that ESIW is sensitive to climate forcing and an important shallow- to mid-depth thermohaline circulation component of EJS