• International Journal of Computer Science & Network Security
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• 제21권11호
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• pp.321-327
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• 2021

Mobile devices have recently developed to be an integral part of humans' daily lives because they meet business and personal needs. It is challenging to design a feasible and effective user authentication method for mobile devices because security issues and data privacy threats have significantly increased. Biometric approaches are more effective than traditional authentication methods. Therefore, this paper aims to analyze the existing biometric user authentication methods on mobile platforms, particularly those that use face recognition, to demonstrate the methods' feasibility and challenges. Next, this paper evaluates the methods according to seven characteristics: universality, uniqueness, permanence, collectability, performance, acceptability, and circumvention. Last, this paper suggests that solely using the method of biometric authentication is not enough to identify whether users are authentic based on biometric traits.

• Journal of applied mathematics & informatics
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• 제41권1호
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• pp.11-31
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• 2023

The paper presents a critical analysis of selected topics related to the modeling of interacting species in which prey has nonlinear reproduction, which is in competition with predator. The mathematical model's stochastic stability is investigated. The method of designing appropriate Lyapunov functions is used to identify permanence conditions among the parameters of the model and conditions for the structure to no longer be extinct. The system's two-dimensional diffusive stability is regarded and studied. The system experiences the process of saddle-node bifurcation by varying the death rate of predator parameter. Further effects of parameters that undergo inherent oscillations are numerically investigated, revealing that as the intensity of predation parameter b is increased, the device encounters non-periodic and damped oscillations.

• 한국해양환경ㆍ에너지학회지
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• 제14권1호
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• pp.51-64
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• 2011

기후변화 완화를 위한 온실가스 감축 수단으로서 이산화탄소를 포집하여 저장하는 이산화탄소 포집 및 저장(CCS) 기술의 중요성이 날로 부각되고 있다. CCS 기술은 발전소 등 대규모 배출원에서 배출되는 대량의 이산화탄소를 바로 감축 가능케 할뿐 아니라 경제 성장을 위한 탄소 에너지 산업 구조를 지속 가능하게 한다. 이러한 CCS 기술의 유용성으로 인해 현재 기후변화협약회의(UNFCCC)에서 청정개발체제(CDM)로 수용하는 방안을 논의 중이다. 그러나 CCS 사업을 CDM 체제로 수용함을 논의함에 있어서 몇몇 이슈들이 제기되고 있는데, 여기에는 i) 장기 영구성을 포함한 비영속성 ii) 측정, 보고 및 검증(MRV), iii) 환경 영향, iv) 사업 범위, v) 국제법, vi) 책임문제, vii) 부당한 성과, viii) 안전성 그리고 ix) 보험 등이 포함된다. 본 논문에서는 이러한 이슈들을 정리 및 분석하고, 이를 통해 현재 우리나라가 계획하고 있는 CCS 실용화를 위해 선행되어야 할 정책적 고려 사항을 도출하고자 한다.

• 펄프종이기술
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• 제45권3호
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• pp.1-8
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• 2013

Hanji has been used mainly for preservation paper because of superior mechanical properties. However, it was not used in printing for inkjet and laser printer-printed letters. In this study, machine-made Hanji was prepared with five different contents of paper mulberry 20, 40, 60, 80 and 100% and managed by same pressure calendering. By increasing of paper mulberry contents, tearing index and folding endurance of machine-made Hanji increased because of increased fiber-to-fiber bonding. Printability property of machine-made Hanji improved by decreasing of paper mulberry contents. After 20 hours accelerated aging, the initial folding endurance of machine-made Hanji was reduced by approximately one-fourth degree. Between 40 and 100% contents of paper mulberry was showed similar levels about preservation property. The machine-made Hanji of paper mulberry 60% content was suitable for permanence and printability properties using preservation paper and printer-printed letters.

• 한국의류산업학회지
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• 제15권1호
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• pp.1-11
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• 2013

This study analyzed the expressive characteristics of padding in contemporary fashion. The methodology of this study was quantified through documentaries, fashion collections, and internet news. The results of expressive characteristics and methods were as follow. First, variability showed the creation of dwelling space by air filling, detail mode by zipper, and diversity of recycled filling by zipper pocket. It reflected the pursuit of nomadism and subversion of permanence by change of filling. Second, it was sexual symbolicity that showed the blurred androgynous silhouette by air filling and padding bar design of the chest, stomach, shoulder for the male body silhouette. It emphasized male sexual identity and power through the expression of a modern ideal body. Third, decoration displayed various crafts (such as knitting), various fabric such as polapolis, suedette, corduroy, denim, leather, knit, and spangle. It reflected visual pleasure, scarcity and various interpretations. Fourth, playfulness character forms throug hair filling, unfamiliar fashion items, diversity of silhouette and change of uses. It reflected a pleasant feeling through astonishment and surprise, nostalgia involved in memory and childhood play and disembarrassment from reality. Fifth, simplicity showed the elimination of a sportswear's factor with regular wad quilting, elimination of wad quilting, wad quilting following the structural line of clothes and the structual line of clothes omitted. It reflected disembarrassment from stereotype and an emphasis on essential elements.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제14권4호
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• pp.225-247
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• 2010

In this paper, we establish a two-competitive-prey and one-predator Holling type II system by introducing a proportional periodic impulsive harvesting for all species and a constant periodic releasing, or immigrating, for the predator at different fixed time. We show the boundedness of the system and find conditions for the local and global stabilities of two-prey-free periodic solutions by using Floquet theory for the impulsive differential equation, small amplitude perturbation skills and comparison techniques. Also, we prove that the system is permanent under some conditions and give sufficient conditions under which one of the two preys is extinct and the remaining two species are permanent. In addition, we take account of the system with seasonality as a periodic forcing term in the intrinsic growth rate of prey population and then find conditions for the stability of the two-prey-free periodic solutions and for the permanence of this system. We discuss the complex dynamical aspects of these systems via bifurcation diagrams.

• 자원ㆍ환경경제연구
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• 제20권3호
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• pp.459-487
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• 2011

포스트 교토체제에서는 A/R CDM 등 산림 분야의 중요성이 증대할 것으로 전망된다. A/R CDM에 대한 정확한 경제성 평가는 투자의사결정에 유용한 정보를 제공하여 투자 활성화로 이어질 수 있다. 본 연구에서는 전통적 경제성 평가 방법이 간과한 의사결정자의 의사결정권의 가치 내지 기다림의 가치를 반영한 실물옵션 방법에 의해 모형을 구축하고 실제 A/R CDM 사례를 적용하여 실증분석을 하였다. 그 결과 적용 사례의 경우 최적투자분기점이 추정된 l-CER의 가격보다 낮게 나타남으로써 적절한 투자의사결정이 이루어졌음을 알 수 있었다. 그러나 할인율의 수준과 적용 범위에 따라 최적투자분기점과 투자의사결정이 크게 영향을 받는 것으로 나타났다.

• 한국게임학회 논문지
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• 제20권4호
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• pp.111-124
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• 2020

본 논문은 학습된 낙관주의 관점에서 '메이플스토리' NPC들의 대화 내용을 분석하였다. NPC의 대화는 게임 이용자들의 재미와 성취욕구 부여에 큰 역할을 하며, NPC와의 반복적이고 장기적인 대화는 유저의 사고에도 영향을 미칠 수 있다. 본 연구에서는 학습된 낙관주의 설명 양식의 핵심적인 2가지 차원인 영속성과 파급성의 요소를 활용하여 분석한 결과, NPC들의 낙관주의적 언어 사용 비율은 대략 6~7%로 확인되었다. 낙관적인 대화성향을 지닌 NPC와 지속적인 소통은 게임 해비유저에게 유사한 사고를 학습할 기회를 부여할 수 있어 향후 NPC인공지능 개발시 중요한 고려사항임을 확인하였다.

• 한국실내디자인학회논문집
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• 제22권1호
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• pp.28-37
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• 2013

Architecture of the present time has a general tendency that focuses only in its permanence between the structure and the ground. Architecture has the temporariness. In other words, it is a losing creation. Structure of natural building materials starts its life on the ground and also ends its life on there. Natural building materials leave no building wastes on their ground. Concerns about how to let materials contain not only its physical property but also their regional relation and timely temporariness can let us express materiality of natural building materials in modern construction spaces. And also, it will be the way of recovering the value of architecture and the healing human's sensibility. Kuma Kengo made an attempt that makes the best use of materiality in his work by using them in balance and draw new materiality by a fusion of them. In here, suggestion about the ways of using weak natural materials in modern construction spaces is the main object of this paper. And we can make a progress by analyzing Kuma's expression way of materiality in his work.

• 한국IT서비스학회지
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• 제15권1호
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• pp.39-66
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• 2016

There is growing evidence that professional work is changing as a result of the application of information technology (IT). However, the impact of information technology on professional work has produced mixed results. Our paper considers the source of these mixed results through a greater analytical attention paid to the nature of professional work. Defined as work involving expertise expressed through abstract and formalized knowledge as well as extensive working knowledge, the professional work logic assumes the greatest autonomy and discretion for workers in collectively controlling work characteristics-division of labor and its permanence, control over education, and control over new entrants and the monitoring and disciplining of existing members. The impact of IT on professional work will be difficult to control and predict without considering the assumptions and tensions within and across the three major types of work logics (Professional, Market and Bureaucratic). Using healthcare as an example, the paper provides various propositions for researching the initiation and effects of ICT design through these three work logics. These propositions illustrate the active role that IS researchers can take in researching an important economic and work-related topic, professional work, and in understanding how ICT affects work-related expertise.