• Journal of the Korea Society for Simulation
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• v.11 no.2
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• pp.1-16
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• 2002

The need for network security is being increasing due to the development of information communication and internet technology. In this paper, firewall models, operating system models and other network component models are constructed. Each model is defined by basic or compound model, referencing DEVS formalism. These models and the simulation environment are implemented with MODSIM III, a general purpose, modular, block-structured high-level programming language which provides direct support for object-oriented programming and discrete-event simulation. In this simulation environment with representative attacks, the following three attacks are generated, SYN flooding and Smurf attack as an attack type of denial of service, Mail bomb attack as an attack type of e-mail. The simulation is performed with the models that exploited various security policies against these attacks. The results of this study show that the modeling method of packet filtering system, proxy system, unix and windows NT operating system. In addition, the results of the simulation show that the analysis of security performance according to various security policies, and the analysis of correlation between availability and confidentiality according to security empowerment.

• Journal of Digital Contents Society
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• v.10 no.2
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• pp.333-340
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• 2009

In the era of Web 2.0, the digital contents are becoming major cultural subjects and the scope and added value of digital content technology industry keep increasing. In order to prevent thoughtless expansion of consumption oriented contents to the multimedia motion picture generation and promote the contents industry in educational, industrial or cultural aspect, educational contents should be specialized as strategic products with increased educational and entertaining meaning. As a result, this study analyzed characteristics of users regarding how educational game contents are distributed to consumers by both male and female group. Then, it extracted development factors for expansion of educational games and presented direction to educational game contents development by using educational games according to changes in users in order to secure mobile flat form contents for effective learning.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1989-1992
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• 2012

We present a low temperature (${\approx}70^{\circ}C$) method to prepare anatase, vertically aligned feather-like $TiO_2$ (VAFT) nanowire arrays $via$ reactive pulsed DC magnetron sputtering. The synthesis method is general, offering a promising strategy for preparing crystalline nanowire metal oxide films for applications including gas sensing, photocatalysis, and 3rd generation photovoltaics. As an example application, anatase nanowire films are grown on fluorine doped tin oxide coated glass substrates and used as the photoanode in dye sensitized solar cells (DSSCs). AM1.5G power conversion efficiencies for the solar cells made of 1 ${\mu}m$ thick VAFT have reached 0.42%, which compares favorably to solar cells made of the same thickness P25 $TiO_2$ (0.35%).

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.2
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• pp.17-30
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• 2015

Technology-oriented national R&D programs produce intellectual property as their final result. Patents, as typical industrial intellectual property, are therefore considered an important factor when evaluating the outcome of R&D programs. Among the main components of patent evaluation, in particular, the patent right quality is a key component constituting patent value, together with marketability and usability. Current approaches for patent right quality evaluation rely mostly on intrinsic knowledge of patent attorneys, and the recent rapid increase of national R&D patents is making expert-based evaluation costly and time-consuming. Therefore, this study defines a hierarchy of patent right quality and then proposes how to quantify the evaluation process of patent right quality by combining text mining and regression analysis. This study will contribute to understanding of the systemic view of the patent right quality evaluation, as well as be an efficient aid for evaluating patents in R&D program assessment processes.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.4
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• pp.153-160
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• 2009

In the research-oriented university there are various laboratories in the departments according to a major field of study. Under these circumstances the budget to purchase experimental facilities has only to be distributed among research teams and then is spent within the confines of it without rein. However, in case of college the budget for experimental facilities needs to be considered other allocation methods because of no laboratory being managed by professor. In this paper the methodology for the rational selection of experimental facilities for college is proposed. It is composed of the following ; (1) the rational allocation method of the budget for experimental facilities in consideration of the characteristics of individual departments, and (2) the evaluation and selection of the alternative experimental facilities submitting in each department. To decide rationally importance of estimation index for the determination of budget and equipment is applied the Analytic Hierarchy Process(AHP) technique. First the proposed methods are presented and then discussed with simulation results.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.2
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• pp.189-198
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• 2001

We are living in the 21st century when a society is highly information-oriented and the demand for information has rapidly increased. So the information standard of local government has become an index of economic development of local society. GIS has emerged as a new national information infrastructure with which a society can manage and analyze spatial information. Accordingly, many local governments have recognized the importance of GIS and are establishing master plan for an efficient GIS development necessary to implement GIS technology in many aspects of information management. So this study analyzed the present status and problems of master plan made by local governments and proposed a guideline for improving GIS master plan on a basis of it.

• Journal of Electrical Engineering and Technology
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• v.2 no.1
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• pp.42-49
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• 2007

For electricity markets to function in a truly competitive and efficient manner, it is not enough to focus solely on improving the efficiencies of power supply. To recognize price-responsive load as a reliability resource, the customer must be provided with price signals and an instrument to respond to these signals, preferably automatically. This paper attempts to develop the Windows-based load management system in competitive electricity markets, allowing the user to monitor the current energy consumption or billing information, to analyze the historical data, and to implement the consumption strategy for cost savings with nine possible scenarios adopted. Finally, this modeling framework will serve as a template containing the basic concepts that any load management system should address.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1195-1202
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• 2017

Induction motors often reach their maximum efficiency at the nominal load. In most applications, the machine load is not equal to the nominal load, thus reduces the motor efficiency and turns a greater percent of power into loss. In this paper, the induction motor control problem has been investigated to reduce the system losses. The Field Oriented Control method (FOC) has been employed in this paper. In this research, the mathematical equations related to system losses are calculated in relation to torque and speed, and then the q- and d-axis are summarized according to the current components. After that, the proposed method is applied along with d- and q-axis. In the recent three decades, many techniques have been suggested to improve the induction motor performance using smart and non-smart methods. In this paper, a new PSO-Fuzzy method have used in real time. The fuzzy logic method serves as speed controller in q-axis and PSO algorithm controls the optimum flux in d-axis. It will be proved that the use of this combined method will lead to a significant improvement in motor efficiency.

• Journal of the Korean Institute of Landscape Architecture
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• v.24 no.4
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• pp.123-131
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• 1997

Since the industrial revolution. the growth of cities has been especially apid and the rate of ulbanization has been high. This urban development is encroaching on the natural environment because the cities are developed with not only residential estates, industrial area and buildings but also with infrastructure. The surface area of the city is sealed ,with pavement whereas nature is disturbed and modified. The hydrological cycle in the city is inf1uenced by the change of land use I. e., from forest to agricultural land, talc draining of wetlands and above all the increase of built-up areas. The surface retention and interception of precipitation in the city is reduced. because the surface area is now smooth and solid. The characteristics of the hydrological cycle in the city are increased runoff, reduced evapotranspiration and infiltraction . We have too much faith in technology although it may cause more unforseen problems. We build more river banks and 'emulation dams and straighten rivers and streams in order to protect ourselves from disasters.. However. the results of hose developments are often higher$.$ water levels, the disturbance of aquatic ecosystems and the reduction of biodiversity. Therefore, we should examine problems from the hydrological cycle in cities and study a natural system as close cities to nature as possible. This paper shows the problems caused by the hydrological cycle in the city. The ecology-oriented method and design must be used in order to protect our environment from dicturbance.

• Journal of Information Technology Services
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• v.9 no.4
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• pp.231-242
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• 2010

The emergence of convergence has been the cause of development of the industry more complex and difficult by continually changing business environment and the destruction of the business area. The government-initiatives approach shows the limits to foster the new industries in needs of service-oriented ecosystem. In this study, we propose the service model as service-based approach for the development of new industries derived through the convergence inter-industry. While business model is defined based on the company's temporary and piecemeal activities, service model is the concept of dynamic and continuous that includes national, industrial, corporate level. In order to derive the service model, to identify current problems and issues with the public and the private sector is first. Then design the roadmap for the implementation of the desired shape through strategy from optimal rationality and long-term strategy. In this study, we define a service model, and consider when establishing a service model for three dimensional(national, industrial, corporate level) through analyzed by 3Level Service Model. And we also consider characteristics of the service model and approach, present the case of 'New Transit Card Services in Seoul'.