• 한국정보처리학회논문지
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• 제6권11S호
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• pp.3299-3308
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• 1999

One of the most important prerequisites for a successful software process is the collaboration and software requirements negotiation of all stakeholders in the software development process. Remote users using computer networks can negotiate software requirements by computer supported system, and can share their informations. The goal of software requirements negotiation system is an integration of all win conditions and an agreement after resolution of conflicts. The existing systems need an exclusive system and must be dependent on specific platform and network. Users must have the knowledge of all stakeholder's status and use homogeneous collaborating applications. This paper presents the Web-based software requirements negotiation system for the purpose of resolution of the existing systems' problems. The Web-based software requirements negotiation system can be driven by WinWin Spiral model, and it is based on hybrid execution method. The proposed system is validated and tested on heterogeneous environments.

• Structural Engineering and Mechanics
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• 제51권6호
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• pp.939-953
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• 2014

Using the infinitesimal theory of elasticity and analytical formulation based on the first-order shear deformation theory (FSDT) is presented for axisymmetric thick-walled cylinders made of functionally graded materials under internal and/or external uniform pressure. The material is assumed to be isotropic heterogeneous with constant Poisson's ratio and radially exponentially varying elastic modulus. At first, general governing equations of the FGM thick cylinders are derived by assumptions of the FSDT. Then the obtained equations are solved under the generalized clamped-clamped conditions. The results are compared with the findings of both FSDT and finite element method (FEM).

• 한국통신학회논문지
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• 제32권1B호
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• pp.17-21
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• 2007

본 논문에서는 멀티미디어 네트워크상에서 우선순위가 높은 서비스의 QoS를 보장하며 동시에 프로세서의 에너지 효율을 최대화하는 적응적 온라인 프로세서 관리기법을 제안하였다. 이 기법은 현재 네트워크의 트래픽 상황을 기반으로 하여 실시간으로 프로세서를 관리한다. 제안된 방법의 가장 큰 특징은 상호 상충하는 다양한 성능 메트릭들 사이에 적정한 균형을 이루어 안정적으로 시스템을 운영하는데 있다. 컴퓨터 시뮬레이션을 통하여 기존에 제안된 프로세서 관리기법에 비해 본 논문에서 제안된 방법이 다양한 트래픽 상황에서 우수한 성능을 가지는 것을 확인할 수 있었다.

• East Asian Economic Review
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• 제19권1호
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• pp.39-70
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• 2015

This paper examines the effects of foreign direct investment (FDI) on South Asian economies' output growth, utilizing recent panel cointegration testing and estimation techniques. Annual panel data on eight SAARC (South Asian Association for Regional Cooperation) member countries' macroeconomic variables over the period 1960- 2013 are employed in empirical analysis. Using various heterogeneous panel cointegration and panel causality tests, a bi-directional relationship between FDI and growth is found. We find evidence for both FDI-led growth and growth-induced FDI hypotheses for the South Asian economies over the sample period. Individual member countries exhibit heterogeneity in terms of the direction or existence of causality subject to their idiosyncratic economic conditions. Among various regressors, FDI, financial development, human capital, and government consumption show the most significant positive effects on output growth. As determinants of FDI, GDP, financial development, human capital, and government consumption are found significant in the region. The bi-directional causality between FDI and growth is found robust to the inclusion of other control variables and using different estimation techniques.

• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.83-91
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• 2002

The Red Queen hypothesis for the advantage of sex predicts that pathogens will evolve by increasing fitness with frequent encounters with specific host genotypes. In this study, BMV population size, measured as an indicator of fitness, was investigated during repeated passages through the same, or different host genotypes of the crop host, Hordeum vulgare (barley). Overall, mean BMV concentration within individual hosts was significantly higher in genetically homogeneous compared to heterogeneous host passage lines. In addition, BMV populations, passaged through a specific host variety, showed higher growth in that host variety compared to BMV passaged through varying varieties. These results supports the Red Queen hypothesis. However, the decrease in viral populations during passages contradicts the Red Queen. Nevertheless, the results found here show that even under simplified conditions, pathogens do not evolve in simple, predictable ways. Constraints on pathogen evolution may lead to counterintuitive results.

• Smart Structures and Systems
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• 제19권4호
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• pp.383-391
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• 2017

In this paper, we investigate the impacts of network topology on the performance of a distributed estimation algorithm, namely combine-then-adaptive (CTA) diffusion LMS, based on the data with or without the assumptions of temporal and spatial independence with noisy links. The study covers different network models, including the regular, small-world, random and scale-free whose the performance is analyzed according to the mean stability, mean-square errors, communication cost (link density) and robustness. Simulation results show that the noisy links do not cause divergence in the networks. Also, among the networks, the scale free network (heterogeneous) has the best performance in the steady state of the mean square deviation (MSD) while the regular is the worst case. The robustness of the networks against the issues like node failure and noisier node conditions is discussed as well as providing some guidelines on the design of a network in real condition such that the qualities of estimations are optimized.

• Advances in aircraft and spacecraft science
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• 제5권5호
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• pp.515-531
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• 2018

In this manuscript, buckling response of the functionally graded material (FGM) nanoplate is investigated. Two opposite edges of nanoplate is under linear and nonlinear varying normal stresses. The small-scale effect is considered by Eringen's nonlocal theory. Governing equation are derived by nonlocal theory and Hamilton's principle. Navier's method is used to solve governing equation in simply boundary conditions. The obtained results exactly match the available results in the literature. The results of this research show the important role of nonlocal effect in buckling and stability behavior of nanoplates. In order to study the FG-index effect and different loading condition effects on buckling of rectangular nanoplate, Navier's method is applied and results are presented in various figures and tables.

• 응용통계연구
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• 제21권6호
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• pp.1007-1014
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• 2008

Usability evaluation(UE) experiments are conducted to provide UE practitioners with guidelines for better outcomes. In UE research, significant quantities of empirical results have been accumulated in the past decades. While those results have been anticipated to integrate for producing generalized guidelines, traditional meta-analysis has limitations to combine UE empirical results that often show considerable heterogeneity. In this study, a new data mining method called weighted bi-clustering(WBC) was proposed to partition heterogeneous studies into homogeneous subsets. We applied the WBC to UE empirical results and identified two homogeneous subsets, each of which can be meta-analyzed. In addition, interactions between experimental conditions and UE methods were hypothesized based on the resulting partition and some interactions were confirmed via statistical tests.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1999년도 추계학술발표회
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• pp.39-43
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• 1999

불포화대에서 LNAPL의 이동과 분포를 수치 모의를 통하여 예측하였다. 균질한 매질에서 LNAPL의 이동은 조립질 매질에서 빠르고, 세립질 매질에서 더 많은 면적으로 확산되며, 더 많은 LNAPL이 불포화대에 잔류한다. 조립질 매질내에 세립질층이 존재할 경우, 이 층이 지하수면으로부터 멀수록 LNAPL이 많이 포획된다. 조립질 매질에 세립질 또는 더 조립질인 매질이 렌즈 상으로 존재하는 환경에서는, LNAPL이 이들 렌즈를 통과하지 못한다. 불균질한 렌즈가 존재할 때의 LNAPL 분포를 초기조건으로 이용하여, 지하수 면의 수직 이동과 물의 침투에 따른 LNAPL의 이동을 모의하였다. 두 경우 모두 불포화대에 잔류되어 있던 LNAPL의 수직방향 이동이 증가되었다. 특히, 지하수면의 하강 시 LNAPL이 조립질 렌즈를 통해 이동하나, 세립질 렌즈를 통해서는 이동하지 못한다.

• 신재생에너지
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• 제2권4호
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• pp.56-63
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• 2006

In this paper, heat and mass transfer characteristics through experimental and numerical study are extensively investigated in steam reforming reactor under given operating conditions. In order to get simulated data at outlet of the reformer, heterogeneous reactor model is incorporated. As the reaction also takes place in porous media, two medium approach is used to take into account thermally non-equilibrium phenomena between catalyst and bulk gas. From various parametric studies, significance of heat transfer is emphasized in steam reforming reaction.