• The Journal of Information Systems
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• v.5
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• pp.149-173
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• 1996

This paper focus on the development of object-oriented model bases for Structured Modeling. For the model base organization, object modeling techniques and model typing concept which is similar to data typing concept are used. Structured modeling formalizes the notion of a definitional system as a way of dscribing models. From the object-oriented concept, a structured model can be represented as follows. Each group of similar elements(genus) is represented by a composite class. Other type of genera can be represented in a similar manner. This hierarchical class composition gives rise to an acyclic class-composition graph which corresponds with the genus graph of structured model. Nodes in this graph are instantiated to represent the elemental graph for a specific model. Taking this class composition process one step further, we aggregate the classes into higher-level composite classes which would correspond to the structured modeling notion of a module. Finally, the model itself is then represented by a composite class having attributes each of whose domain is a composite class representing one of the modules. The resulting class-composition graph represent the modular tree of the structured.

• Geomechanics and Engineering
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• v.7 no.2
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• pp.213-231
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• 2014

An elastoplastic model for structured clays, which is formulated based on the fact that the difference in mechanical behavior of structured and reconstituted clays is caused by the change of fabric in the post-yield deformation range, is present in this paper. This model is developed from an elastoplastic model for overconsolidated reconstituted clays, by considering that the variation in the yield surface of structured clays is similar to that of overconsolidated reconstituted clays. However, in order to describe the mechanical behavior of structured clays with precision, the model takes the bonding and parabolic strength envelope into consideration. Compared with the Cam-clay model, only two new parameters are required in the model for structured clays, which can be determined from isotropic compression and triaxial shear tests at different confining pressures. The comparison of model predictions and results of drained and undrained triaxial shear tests on four different marine clays shows that the model can capture reasonable well the strength and deformation characteristics of structured clays, including negative and positive dilatancy, strain-hardening and softening during shearing.

• Journal of the Korean Operations Research and Management Science Society
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• v.15 no.2
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• pp.85-95
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• 1990

Structured modeling provides a formal mathematical framework, language, and computer-based environment for conceiving, representing, and manipulating a wide variety of model. It provides a natural framework for integrated modeling owing to its explicit representation power for computational dependencies among submodles. Nevertheless, it doesn't seem to offer a systematic way of composing a structured model from submodels. In order to develop a systematic way, this paper discusses three key issues : (1) Genus structure for model composition, (2) Storage of structured models, and (3) Integration of structured models. To formalize and visualize the approach, a programming module is developed to implemented the step-by-step integration.

• Geomechanics and Engineering
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• v.18 no.2
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• pp.121-131
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• 2019

This article discusses the phenomenon of plastic volumetric deformation of naturally structured clays before virgin yielding, i.e., subyielding behavior. A simple approach representing both the compression and shear responses of the clays during subyielding is demonstrated. A new compression model for structured clays based on the theoretical framework of the Structured Cam Clay (SCC) model via incorporation of the subyielding behavior is presented. Two stress surfaces are introduced to distinguish the subyielding and virgin yielding. The hardening and destructuring processes of structured clays under isotropic compression and shear are the focus of this work. The simulations of the compression and shear of eleven natural clays are studied for validation. The proposed work can accurately predict the subyielding behavior of structured clays both qualitatively and quantitatively and can be used for modeling structured clays under compression and shear responses in geological and geotechnical engineering problems.

• Transactions on Semiconductor Engineering
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• v.1 no.1
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• pp.23-30
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• 2023

With the recent development of Generative AI technology by IT giants, the size of the transformer model is increasing exponentially over trillion won. In order to continuously enable these AI services, it is essential to reduce the weight of the model. In this paper, we find a hardware-friendly structured pruning pattern and propose a lightweight method of the transformer model. Since compression proceeds by utilizing the characteristics of the model algorithm, the size of the model can be reduced and performance can be maintained as much as possible. Experiments show that the structured pruning proposed when pruning GPT-2 and BERT language models shows almost similar performance to fine-grained pruning even in highly sparse regions. This approach reduces model parameters by 80% and allows hardware acceleration in structured form with 0.003% accuracy loss compared to fine-tuned pruning.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.8
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• pp.49-56
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• 1993

In this paper, we present a new lifetime prediction model for PMOSFET by using the correlation between transconductance degradation and substrate current influence. The suggested model is applied to a different channel structured PMOSFET, dgm/gm of both SC-PMOSFET and BC-PMOSFET appear with one straigth line about Qbib, therefore, this model is independent of channel structure. The suggested model is applied to a different drain structured SC-PMOSFET. Unlike S/D structured SC-PMOSFET, dgm/gm of LDD structured SC-PMOSFET appears with one straight line about Qb, therefore, this model is dependent of drain structure.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1990.04a
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• pp.49-60
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• 1990

Structured modeling provides a formal mathematical framework, language, and computer-based environment for conceiving, representing, and manipulating a wide variety of models. It provides a natural framework for integrated modeling owing to its explicit representation power for computational dependencies among submodels. Nevertheless, it doesn't seem to offer a systematic way of composing a structured model from submodels. In order to develop a systematic way, this paper discusses three key issues; (1) Genus structure of validated submodel, (2) Storing method of genus structure, and (3) Integration of genus structures to generate a new genus structure. To visualize the approach, a programming module is developed to implement the step-by-step integration.

• Journal of the Korean Data and Information Science Society
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• v.16 no.2
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• pp.301-311
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• 2005

This study has conducted to measure the internet banking customer satisfaction using structured equation model. Data was collected by e-mail system. Among survey panel who had experience of using Hanwha-Bank internet banking service, final samples were 2,848 respondents. The results showed that usage convenience and economy factor was most correlated with customer satisfaction. And we found that word-of-mouth behavior was affected customer satisfaction.

• Journal of the Korean institute of surface engineering
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• v.53 no.6
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• pp.330-342
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• 2020

Since the original report on ferroelectricity in Si-doped HfO2 in 2011, fluorite-structured ferroelectrics have attracted increasing interest due to their scalability, established deposition techniques including atomic layer deposition, and compatibility with the complementary-metal-oxide-semiconductor technology. Especially, the emerging fluorite-structured ferroelectrics are considered promising for the next-generation semiconductor devices such as storage class memories, memory-logic hybrid devices, and neuromorphic computing devices. For achieving the practical semiconductor devices, understanding polarization switching kinetics in fluorite-structured ferroelectrics is an urgent task. To understand the polarization switching kinetics and domain dynamics in this emerging ferroelectric materials, various classical models such as Kolmogorov-Avrami-Ishibashi model, nucleation limited switching model, inhomogeneous field mechanism model, and Du-Chen model have been applied to the fluorite-structured ferroelectrics. However, the polarization switching kinetics of fluorite-structured ferroelectrics are reported to be strongly affected by various nonideal factors such as nanoscale polymorphism, strong effect of defects such as oxygen vacancies and residual impurities, and polycrystallinity with a weak texture. Moreover, some important parameters for polarization switching kinetics and domain dynamics including activation field, domain wall velocity, and switching time distribution have been reported quantitatively different from conventional ferroelectrics such as perovskite-structured ferroelectrics. In this focused review, therefore, the polarization switching kinetics of fluorite-structured ferroelectrics are comprehensively reviewed based on the available literature.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.13 no.1
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• pp.1-11
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• 2009

Current therapies against ulcers caused by H. pylori infection consist of antibiotics, an acid reducer, and some clinical trials underway to develop a H. pylori vaccine. We develop a structured model with age-dependent mortality of peptic ulcers and H. pylori infection. Our main goal is to analyze our structured model mathematically and to compare it to our previously unstructured model to examine the disease transmission dynamics in terms of annual prevalence and annual incidence of the disease.