• Tunnel and Underground Space
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• v.31 no.4
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• pp.270-288
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• 2021

We proposed a numerical method to simulate the hydro-mechanical behavior of rock fracture using a grain-based distinct element model (GBDEM) in the paper. As a part of DECOVALEX-2023 Task G, we verified the method via benchmarks with analytical solutions. DECOVALEX-2023 Task G aims to develop a numerical method to estimate the coupled thermo-hydro-mechanical processes within the crystalline rock fracture network. We represented the rock sample as a group of tetrahedral grains and calculated the interaction of the grains and their interfaces using 3DEC. The micro-parameters of the grains and interfaces were determined by a new methodology based on an equivalent continuum approach. In benchmark modeling, a single fracture embedded in the rock was examined for the effects of fracture inclination and roughness, the boundary stress condition and the applied pressure. The simulation results showed that the developed numerical model reasonably reproduced the fracture slip induced by boundary stress condition, the fracture opening induced by fluid injection, the stress distribution variation with fracture inclination, and the fracture roughness effect. In addition, the fracture displacements associated with the opening and slip showed good agreement with the analytical solutions. We expect the numerical model to be enhanced by continuing collaboration and interaction with other research teams of DECOVALEX-2023 Task G and validated in further study experiments.

• International Commerce and Information Review
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• v.16 no.4
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• pp.263-280
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• 2014

The dynamics of global alliance networks can be analyzed in numerous ways. We have chosen to approach it in terms of alliance stability. Although increasing academic attention has been devoted to the alliance dynamics field, the majority of prior research has neither contributed to a coherent knowledge foundation(an academic gap) nor provided adequate answers to managerial questions(a managerial relevance gap). We respond to their call for research by developing an integrated process model that integrates various studies on alliance stability. The primary tasks were (1) to characterize and conceptualize the stability concept to fill the academic gap, and (2) to identify critical endogenous factors underlying alliance stability over the different developmental stages to fill the managerial gap. Knowledge acquired in this paper is also expected to offer alliance managers and practitioners some valuable implications as they strive for stable and successful collaborative relationships. As one of the basic arguments, stability has been viewed as a necessary condition for the achievement of collaborative objectives. When firms form, implement, adjust and evaluate their alliances, they should have the goal of stability in mind. At the same time, management should be in a position to determine the specific actions needed for stability at any given moment in the alliance's lifetime.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.826-833
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• 2009

Currently, the rise of social tagging has changing taxonomy to folksonomy. Tag represents a new approach to organizing information. Nonhierarchical classification allows data to be freely gathered, allows easy access, and has the ability to move directly to other content topics. Tag is expected to play a key role in clustering various types of contents, it is expand to network in the common interests among users. First, this paper determine the relationships among user, tags and resources in social tagging system and examine the circumstances of what aspects to users when creating a tag related to features of websites. Therefore, this study uses tags from the social bookmarking service 'del.icio.us' to analyze the features of tag words when adding a new web page to a list. To do this, websites features classified into 7 items, it is known as tag classification related to resources. Experiments were conducted to test the proposed classify method in the area of music, photography and games. This paper attempts to investigate the perspective in which users apply a tag to a webpage and establish the capacity of expanding a social service that offers the opportunity to create a new business model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.530-536
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• 2020

The use of minutiae by fingerprint readers is robust against presentation attacks, but one weakness is that the mismatch rate is high. Therefore, minutiae tend to be used with skeleton images. There have been many studies on security vulnerabilities in the characteristics of minutiae, but vulnerability studies on the skeleton are weak, so this study attempts to analyze the vulnerability of presentation attacks against the skeleton. To this end, we propose a method based on the skeleton to recover the original fingerprint using a learning algorithm. The proposed method includes a new learning model, Pix2Pix, which adds a latent vector to the existing Pix2Pix model, thereby generating a natural fingerprint. In the experimental results, the original fingerprint is restored using the proposed machine learning, and then, the restored fingerprint is the input for the fingerprint reader in order to achieve a good recognition rate. Thus, this study verifies that fingerprint readers using the skeleton are vulnerable to presentation attacks. The approach presented in this paper is expected to be useful in a variety of applications concerning fingerprint restoration, video security, and biometrics.

• Journal of the Korean earth science society
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• v.28 no.2
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• pp.214-226
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• 2007

Because precipitation is influenced by various atmospheric variables, it is highly nonlinear. Although precipitation predicted by a dynamic model can be corrected by using a nonlinear Artificial Neural Network, this approach has limits such as choices of the initial weight, local minima and the number of neurons, etc. In the present paper, we correct simulated precipitation by using a multiple linear regression (MLR) method, which is simple and widely used. First of all, Ensemble hindcast is conducted by the PNU/CME Coupled General Circulation Model (CGCM) (Park and Ahn, 2004) for the period from April to August in 1979-2005. MLR is applied to precipitation simulated by PNU/CME CGCM for the months of June (lead 2), July (lead 3), August (lead 4) and seasonal mean JJA (from June to August) of the Northeast Asian region including the Korean Peninsula $(110^{\circ}-145^{\circ}E,\;25-55^{\circ}N)$. We build the MLR model using a linear relationship between observed precipitation and the hindcasted results from the PNU/CME CGCM. The predictor variables selected from CGCM are precipitation, 500 hPa vertical velocity, 200 hPa divergence, surface air temperature and others. After performing a leave-oneout cross validation, the results are compared with the PNU/CME CGCM's. The results including Heidke skill scores demonstrate that the MLR corrected results have better forecasts than the direct CGCM result for rainfall.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.4
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• pp.265-282
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• 2008

Based on the site characterization works in a low and intermediate level waste(LILW) repository site, the numerical simulations for groundwater flow were carried out in order to understand the groundwater flow system of repository site. To accomplish the groundwater flow modeling in the repository site, the discrete fracture network(DFN) model was constructed using the characteristics of fracture zones and background fractures. At result, the total 10 different hydraulic conductivity(K) fields were obtained from DFN model stochastically and K distributions of constructed mesh were inputted into the 10 cases of groundwater flow simulations in FEFLOW. From the total 10 numerical simulation results, the simulated groundwater levels were strongly governed by topography and the groundwater fluxes were governed by locally existed high permeable fracture zones in repository depth. Especially, the groundwater table was predicted to have several tens meters below the groundwater table compared with the undisturbed condition around disposal silo after construction of underground facilities. After closure of disposal facilities, the groundwater level would be almost recovered within 1 year and have a tendency to keep a steady state of groundwater level in 2 year.

• Journal of the Korean Geographical Society
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• v.44 no.6
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• pp.813-832
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• 2009

As accessibility to health-care service in less populated rural areas is geographically limited and demand for public health-care by the aging is increasing, a new approach for health-care service such as a home care service is becoming more popular. For a home care service, health-care personnels directly visit to location of health-care clients. Such changes in provision of health services require developing innovative and scientific approaches for efficient allocation of health resources and managing services by public health-care organizations. The purpose of this study is to formulate a location model for visiting health-care districting for the rural elderly and to develop an Automated Zoning Procedure (AZP) to solve this model. Mobility, workload balance and contiguity criteria are considered in the model. Three different objective functions are evaluated; 1) minimizing the sum of network distance between the unit areas in a district, 2) maximizing spatial interaction between the unit areas in a district, and 3) minimizing tour distance that visits each unit area exactly once in a district. The AZP for solving the model is developed and applied to a rural area. The application results demonstrate that the AZP can generate different districting systems for each objective functions.

• International Commerce and Information Review
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• v.14 no.4
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• pp.89-107
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• 2012

Recently, the successful appointment of the general directorate of GCF (Green Climate Fund) in Songdo of Korea made a great history for the golden triangle with GGGI (global Green Growth Institute) and GTC (Green Technology Center). Now, Korea became the Mecca for the global green growth and it gave a great opportunity foe the Korea to lead the global economy in the future. However, to successfully manage the GCF, the Korean government should show their willingness as well as the readiness for the green prowth and green productivity. It is really hard for the Korea, since it takes the second rank for the growth rate of carbon dioxide emission in the world. To overcome this shameful status, it should make the best effort to promote the green productivity, especially in a field of logistics industry, because it takes 21% of global CO2 emission, the second largest portion. The research aims to systematically introduce the Global Malmquist-Luenberger Index (GML) and to evaluate the logistics industry of Korea based on the GML approach. It concludes the innovative technology is utmost important to improve the green productivity of the logistics industry and thus the Korean government should make more aggressive role to fill this missing link in the innovation network.

• Archives of design research
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• v.17 no.3
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• pp.81-90
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• 2004

The reason of the appearance of Internet is regarded as a milestone since we have shared information globally in a mutual way. The important thing on this point is what contents we choose for ourselves. The Internet could be meaningless unless we use it in a certain way, which ultimately means that the Internet has to deliver something valuable to us humans. Therefore, we have looked at how we can deliver and share humanity and emotion through the Internet, also how we can instill vital power into our real life, through the Internet. Fortunately, the current study must essentially be ongoing due to its nature with perhaps a multidisciplinary team brainstorming ideas. The reason for that is that not only could we find new business models for companies, but also find out new ways to appease the human mind in the modern age. In addition, as consumers needs become more specialized and diversified, companies are expected to face up to fierce competition with the help of innovative ideas. The ever-intensifying competition requires companies to cultivate new strategic tools in order to have new, powerful and sustainable comparative advantages. The goal of this research will be to explore ways of finding a new approach. Specifically, this research is about how to use the EVC(empathetic virtual character), which, this researcher believes, can deliver emotional benefits so as to make e-branding successful. According to reports, it has been proven that this new concept including the EVC can result in tremendous success. So the goal of this research is to explore the current situation and to anticipate the future concerning virtual characters.

• Journal of KIISE
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• v.42 no.5
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• pp.591-600
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• 2015

SLA (Service Level Agreement) is an essential factor that must be guaranteed to provide a reliable and consistent service to user in cloud computing environment. Especially, a contract between user and service provider with SLA is important in an environment using a cloud service brokerage. The cloud computing is classified into IaaS, PaaS, and SaaS according to IT resources of the various cloud service. The existing SLA is difficult to reflect the quality factors of service, because it only considers factors about the physical Network environment and have no methodological approach. In this paper, we suggested a method to specify the quality characteristics of software and proposed a mechanism and structure that can exchange SLA specification between the service provider and consumer. We defined a meta-model for the SLA specification in the SaaS level, and quality requirements of the SaaS were described by the proposed specification language. Through case studies, we verified proposed specification language that can present a variety of software quality factors. By using the UDDI-based mediation process and architecture to interchange this specification, it is stored in the repository of quality specifications and exchanged during service binding time.