• The Bulletin of The Korean Astronomical Society
• /
• v.46 no.2
• /
• pp.44.3-45
• /
• 2021

일반화된 excursion set 이론과 자기 유사 구형 유입(Self-similar spherical infall) 모형에 기반하여 Splashback 질량함수에 대한 해석적 단일 매개변수 모델을 착안하였다. Planck/WMAP7 관측결과를 토대로 구축된 EREBOS N-Body 시뮬레이션의 수치적 결과의 해석적 모델을 이용한 회귀분석을 통해 단일 매개변수이자 Splashback 경계의 확산적 특성을 수치화하는 확산계수(Diffusion Coefficient)의 추정치를 계산하였다. 계산된 확산계수를 적용한 해석적 모델과 수치적 결과가 5 ≤ M/(10¹²h^-1 M_⊙) < 10³의 질량범위에서 매우 근접히 일치하는 것을 보였으며 Baysian and Akaike Information Criterion 검정을 통해 0.3 ≤ z ≤ 3의 범위에서 기존의 모델들보다 본 모델이 선호 돼야함을 확인하였다. 또한 확산계수가 적색편이에 대하여 선형진화에 근접한 변화를 보임을 발견하였으며, 특정 임계 적색편이(z_c)를 기준으로 확산계수가 0에 수렴함을 발견하였다. 더 나아가 두 Planck모델과 WMAP7모델에서 도출된 확산계수는 서로 상당한 차이를 보였다. 이 결과는 암흑물질 헤일로의 splashback 질량함수가 z ≥ z_c에서 매개변수가 없는 온전한 해석적 모델로 설명되고 z_c가 독립적으로 우주의 초기조건을 독립적으로 특정지을 수 있는 가능성을 지님을 시사한다. 이 초록은 The Astrophysical Journal의 Ryu & Lee 2021, ApJ, 917, 98 (arxiv:2103.00730) 논문을 바탕으로 작성되었다.

• Journal of the Economic Geographical Society of Korea
• /
• v.13 no.2
• /
• pp.196-218
• /
• 2010

This study is to investigate the development process and the structure of the machine and material industrial clusters in Yeongnam region, Korea. In theoretical analysis, it is proposed that the wide area industrial cluster has three type of development process and a duplicate (or multi-level) spatial structure. We can ascertain from the case study of industrial clusters in Yeongnam region that An wide machine and material industrial cluster has been formed in Yeongnam region and the cluster has the duplicate structure or multi-level structure.

• The Journal of the Korea Contents Association
• /
• v.15 no.7
• /
• pp.128-137
• /
• 2015

Going through rapid changes, the field of information technology (IT) has launched many innovative products. Some of those products have spread, forming a stable market, whereas others have disappeared. The purpose of the study is to purpose a theoretical model to show changes in the importance of competition factors over the three stages. Our study applied the innovation adoption stage model of the Innovation Diffusion Theory (IDT) to the industry life cycle of the Industry Life Cycle (ILC) Theory resulting in three stage of introduction, growth, and maturity, and defined a model of market characteristics according to time. By using the model, we analyzed the case of notebook computers and tablet and checked the fitness of the model. Results show that five competition factors worked differently according to time. In the introduction stage, relative functionality and relative playfulness are important competition factors. In the growth stage, compatibility is added to those two factors. In the last maturity stage, compatibility, complexity, and cost level are important competition factors.

• Journal of Internet Computing and Services
• /
• v.11 no.5
• /
• pp.37-58
• /
• 2010

This study analyzes appropriate government policy frameworks for promoting IPTV industry by studying the way of adoption and diffusion of IPTV services. Until recently, most researches on government policies for technology adoption have focused on the personal context. This research adopts two theories, i.e., innovation characteristics theory for personal context and implementation process theory for organizational context. It also hypothesizes that the innovation characteristics more influence on the behavioral intention for usage new media in the level of personal innovativeness is high. Moreover, in the level of expectancy for diffusion policy is high, the implementation of IPTV services more influences on the behavioral intention. The results by statistical analysis, it is found that the higher the level of personal innovativeness is, and the higher the level of expectancy for diffusion policy is, the more behavioral intention will be influenced by the characteristics of innovation and implementation of IPTV service. Thus it is important for government agencies to find the way to facilitate personal innovativeness as well as expectancy for diffusion policy.

• Journal of the Korean Society for information Management
• /
• v.28 no.4
• /
• pp.141-160
• /
• 2011

This study examined perceptions of 109 professors at doctorate-granting universities in the U.S. who have self-archived in Institutional Repositories(IRs), predicated on the Diffusion of Innovations Theory. The majority of the faculty learned about IRs through the contact from IR staff or their presentations. Relating to five characteristics of an innovation, digital preservation and usage statistics of an IR were considered to be its relative advantage. The principle of Open Access(OA) was found to have compatibility with the values that professors ultimately pursued. The trialability of an IR was determined by the fact that IRs were adopted by faculty through the participation of pilot projects. Professors who gained positive and visible results from IR adoption seemed more strongly support the repository. In addition, it is necessary for IRs to provide stable and effective services that support the continued adoption of IRs.

• Journal of KIISE:Software and Applications
• /
• v.32 no.11
• /
• pp.1059-1070
• /
• 2005

For genetic algorithms, the population may get stuck in a local optimum. The population can escape from this after a long duration. This phenomenon is called punctuated equilibrium. The punctuated equilibria observed in nature and computational ecosystems are known to be well described by diffusion equations. In this paper, simple genetic algorithms are theoretically analyzed to show that they can also be described by a diffusion equation. When fitness is the function of unitation, this analysis can be further refined to make the parameters of genetic algorithms appear in this equation. Using theoretical results on the diffusion equation, the duration of equilibrium is shown to be exponential of such parameters as population size, 1/(mutation probability), and potential barrier. This is corroborated by simulation results for bistable potential landscapes with one local optimum and one global optimum.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.5
• /
• pp.1219-1226
• /
• 2013

The purpose of this study was aimed to analyze factors affecting on continuous intention to use of Smartphone based on the innovation diffusion theory. Also, by using the demographic characteristics were compared whether the difference in the loyalty on between user group of iOS and Android platform. Predictor factors were selected innovation, convenience, economic cost, social influence, communication channel, compatibility and complexity suggested on the innovation diffusion theory. Participants of this study were 278 Smartphone users in Busan city and Gyeongnam province in accordance with convenience sampling. IBM SPSS Statistics 19 were employed for descriptive statistics, Smart PLS(partial least squares) was employed for confirmatory factor analysis and path analysis of casual relationship among variables and effect. Analytical results show that all paths except path from complexity to the continuous intention to use and loyalty are significant. The comparison loyalty on between user group of iOS and android platform are significant. This study suggests practical and theoretical implications based on the results.

• Journal of Digital Convergence
• /
• v.17 no.1
• /
• pp.43-53
• /
• 2019

This study has explored the trajectory of the development and diffusion of the CTLs in the Korean universities by using isomorphism theory of neo-institutionalism. Neo-institutional theorists believe that organizational structure and behavior reflects the norms and values recognized in the society rather than the organization's autonomous and rational choices. Based on the isomorphism framework, the introduction and diffusion of the CTLs in the Korean universities have been led by the government. In addition, the CTLS(Korean Association of Center for Teaching & Learning) has served as a direct basis for the normative pressures. In other words, the CTLs have been securing devices for the universities to acquire external justification by the environment, and they have been able to confirm that the system was isomorphed, in particular by meeting and agreeing with the government-set university evaluation criteria. Efforts should be made to develop unique values and strategies that enable CTLs to become engines of the development of university education in response to rapid changes in the academic environment.

• 한국벤처창업학회:학술대회논문집
• /
• 2020.11a
• /
• pp.47-53
• /
• 2020

빅데이터 기술은 기업의 경쟁력을 높일 수 있는 혁신 기술 중 하나로 급성장하고 있는 가운데 농업 분야 또한 빅데이터를 활용한 경쟁력 제고와 미래 산업으로의 발전이 중요 당면과제로 부상하고 있다. 해외의 경우 농업 빅데이터를 활용한 스타트업이 빠른 속도로 증가하며 성장하는 반면 국내의 경우 생산 분야 일부 농업 벤처 외에는 빅데이터 활용이 미흡한 실정이다. 또한 기업의 빅데이터 활용수준이나 활용의도에 영향을 미치는 요인에 대한 연구가 대기업이나 특정 산업에 국한되어 이루어지고 있으며, 연구마다 영향요인 변수의 검증결과가 상이하게 나타나 산업/기업특성에 따라 연구가 필요하다. 본 연구의 목적은 농업벤처기업에서 새로운 ICT인 빅데이터를 도입하고 사용하는 데 영향을 미치는 요인을 파악하고, 이를 통해 기대하는 편익에 대해 파악함으로써 활용을 촉진할 수 있는 방안을 제시하는 데 있다. 본 연구는 빅데이터가 조직의 프로세스를 변화시키고, 최고경영층의 지원이 필수적이며, 기업이 처한 환경적 압박에 대응할 수 있는 수단으로 보고 기술·조직·환경(TOE: Technology-Organization-Environment) 프레임워크를 기반으로 혁신확산이론(Diffusion of Innovation Theory) 모형을 결합하여 본 연구에 적합한 변수들을 도출한 후 이들 변수간의 인과관계를 설정하여 연구모형을 구성하였다. 이에 따라 TOE모형의 기술적 요인에 관한 변수로는 혁신확산이론 변수인 상대적이점, 호환성, 복잡성을 채택하였고, 조직적 요인에 관한 변수로 최고경영층 지원, 비용부담능력을, 환경적 요인에 관한 변수로는 법적·정책적 지원, 경쟁자 압력을 채택하였다. 이들 3가지 요인에 속한 7가지 변수들과 빅데이터 사용의도와 기대편익 간의 관련성, 그리고 농업벤처 사업분야의 조절효과에 대한 8개의 가설을 설정하였다. 본 연구는 실제 농업벤처기업 종사자 대상 설문을 통한 실증연구를 통해 벤처 현장에서의 빅데이터 활용수준을 높이기 위한 기술적, 조직적, 환경적 관점의 정책 개선방안을 제시하고, 생산/가공/유통 등 사업분야별 비교를 통해 영향요인의 중요도 차이를 규명해 영역별로 차별적이고 효과적인 정책 방향성을 도출하는 데 시사점을 제시하고자 한다.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.4A
• /
• pp.365-371
• /
• 2009

It is time-consuming to estimate chloride diffusivity of concrete by concentration difference test. For the reason chloride diffusivity of concrete is mainly tested by electrically accelerated method, which is accelerating the movement of chloride ion by potential difference. In this study, portland cement concrete and concrete containing with ground granulated blast-furnace slag (40 and 60% of cement by weight) with water-cementitious material ratio 40, 45, 50 and 60% were manufactured. To compare with chloride diffusivity calculated from the electrically accelerated test and immersed test in artifical seawater, chloride diffusivity tests were conducted. From the results of regression analysis, regression equation between accelerated chloride diffusivity and immersed chloride diffusivity was linear function. And the determinant coefficient was 0.96 for linear equation.