• 제목/요약/키워드: local model

검색결과 5,494건 처리시간 0.039초

난류유동해석을 통한 환기효율의 수치해석적 연구 (Numerical Analysis of Ventilation Effectiveness using Turbulent Airflow Modeling)

  • 한화택
    • 설비공학논문집
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    • 제4권4호
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    • pp.253-262
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    • 1992
  • A numerical procedure is introduced to calculate local ventilation effectiveness using the definitions of local decay rate and local mean age. A low Reynolds number $k-{\varepsilon}$ model is implemented to calculate steady state turbulent velocity distributions, and a step-down method is used to calculate transient concentration distributions. Simulations are carried out for several different values of air change rates and several different diffuser angles in a two-dimensional model of a half scale office room. The results show that the local ventilation effectiveness within a room could vary significantly from one location to another. The nominal air change rate based on the assumption of complete mixing of room air does not provide the local ventilation effectiveness information. It is numerically proved that the local mean age distribution obtained from the transient calculation is equivalent to the steady state concentration distribution with homogeneously distributed contaminant sources.

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A Video Cache Replacement Scheme based on Local Video Popularity and Video Size for MEC Servers

  • Liu, Pingshan;Liu, Shaoxing;Cai, Zhangjing;Lu, Dianjie;Huang, Guimin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권9호
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    • pp.3043-3067
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    • 2022
  • With the mobile traffic in the network increases exponentially, multi-access edge computing (MEC) develops rapidly. MEC servers are deployed geo-distribution, which serve many mobile terminals locally to improve users' QoE (Quality of Experience). When the cache space of a MEC server is full, how to replace the cached videos is an important problem. The problem is also called the cache replacement problem, which becomes more complex due to the dynamic video popularity and the varied video sizes. Therefore, we proposed a new cache replacement scheme based on local video popularity and video size to solve the cache replacement problem of MEC servers. First, we built a local video popularity model, which is composed of a popularity rise model and a popularity attenuation model. Furthermore, the popularity attenuation model incorporates a frequency-dependent attenuation model and a frequency-independent attenuation model. Second, we formulated a utility based on local video popularity and video size. Moreover, the weights of local video popularity and video size were quantitatively analyzed by using the information entropy. Finally, we conducted extensive simulation experiments based on the proposed scheme and some compared schemes. The simulation results showed that our proposed scheme performs better than the compared schemes in terms of hit rate, average delay, and server load under different network configurations.

Analysis of the Effect of Local Universities on the Local Economy - Based on the Daranee Analysis -

  • Sung Hyun Park;Ki beom Kim
    • International Journal of Internet, Broadcasting and Communication
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    • 제15권2호
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    • pp.73-80
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    • 2023
  • As a result of this study, the income generation effect of local universities on the local economy through the Daranee (1976) model was found to be 110.9 billion won (direct and indirect income 78 billion won, induced income 32.9 billion won). In the case of Korea, it has been verified through a number of previous studies that local universities play a role in preventing the outflow of local talent to the metropolitan area. Considering this, it seems that the government should make bold investments to foster local universities in terms of balanced national development. This is because the movement of local talents to the metropolitan area not only undermines the growth potential of the provinces and undermines the basis for regional existence, but also creates a vicious cycle that hinders balanced national development. To break this vicious cycle, the development of local universities is very important. It is judged that the horizon of balanced national development will be opened when local universities revitalize the local economy through the government's bold investment in local universities and are reborn as entities that provide various services based on the facilities and equipment of local universities.

Three-Dimensional Shape Recognition and Classification Using Local Features of Model Views and Sparse Representation of Shape Descriptors

  • Kanaan, Hussein;Behrad, Alireza
    • Journal of Information Processing Systems
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    • 제16권2호
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    • pp.343-359
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    • 2020
  • In this paper, a new algorithm is proposed for three-dimensional (3D) shape recognition using local features of model views and its sparse representation. The algorithm starts with the normalization of 3D models and the extraction of 2D views from uniformly distributed viewpoints. Consequently, the 2D views are stacked over each other to from view cubes. The algorithm employs the descriptors of 3D local features in the view cubes after applying Gabor filters in various directions as the initial features for 3D shape recognition. In the training stage, we store some 3D local features to build the prototype dictionary of local features. To extract an intermediate feature vector, we measure the similarity between the local descriptors of a shape model and the local features of the prototype dictionary. We represent the intermediate feature vectors of 3D models in the sparse domain to obtain the final descriptors of the models. Finally, support vector machine classifiers are used to recognize the 3D models. Experimental results using the Princeton Shape Benchmark database showed the average recognition rate of 89.7% using 20 views. We compared the proposed approach with state-of-the-art approaches and the results showed the effectiveness of the proposed algorithm.

위치문답형 지역광고 기반의 문화정보 서비스 모델링 (Regional Culture Contents Service Modeling Based On Localized Advertising of Question And Answer Format)

  • 신환섭;이재원
    • 한국콘텐츠학회논문지
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    • 제19권8호
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    • pp.465-472
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    • 2019
  • 지역에서 생산되는 문화행사 및 문화 콘텐츠가 다양하고 많지만 관련한 경제소비의 확대를 위한 지역정보의 유통과 확산이 부족하다. 본 연구는 지역 문화정보의 확산과 사용을 목적으로 위치기반 서비스 관점에서 지역광고주의 지역광고를 질문과 답변 형식의 지식검색 방법과 결합하고 서비스화 하였다. 접근 방법으로는 지역에 기반한 지식검색에 대한 국내외 사례와 위치기반 광고 연구를 살펴보고, 위치문답형 정보서비스의 커뮤니티 모델 그리고 지역광고의 수익 모델을 제시하였다. 이를 통해 본 연구는 지역 문화행사와 문화콘텐츠의 정보유통을 위한 문답기반 커뮤니티와 지역광고의 운영구조 모델을 설계하고 정보 서비스 시스템을 프로토타이핑 형태로 개발하였다. 사용자간의 문답 데이터의 유통을 위치정보에 확장함으로써 지역의 문화콘텐츠 정보와 사용자 접근의 수요를 지역광고의 수익모델과 결합하여 제공하는 비즈니스 서비스 모델을 제시하였다는 의의를 갖는다.

Local & Global 모델을 이용한 용접구조물 변형 해석에 관한 연구 (The Analysis of Welding Deformation in Large Welded Structure by Using Local & Global Model)

  • 장경복;조시훈;장태원
    • Journal of Welding and Joining
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    • 제22권6호
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    • pp.25-29
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    • 2004
  • Some industrial steel structures are composed by components linked by several welding joints to constitute an assembly. The main interest of assembly simulation is to evaluate the global distortion of welded structure. The general method, thermo-elasto-plastic analysis, leads to excessive model size and computation time. In this study, a simplified method called "Local and Global approach" was developed to break down this limit and to provide a accurate solution for distortion. Local and global approach is composed of 3 steps; 1) Local simulation of each welding joint on a dedicated mesh (usually very fine due to high thermal gradients), taking into account for the non linearity of the material properties and the moving heat source. 2) Transfer to the global model of the effects of the welding joints by projection of the plastic strain tensors. 3) Elastic simulation to determine final distortions in global model. The welding deformation test for mock-up structure was performed to verify this approach. The predicted welding distortion by this approach had a good agreement with experiment results.

The Two-Stage Least Squares Regression of the Interplay between Education and Local Roads on Foreign Direct Investment in the Philippines

  • DIZON, Ricardo Laurio;CRUZ, Zita Ann Escabarte
    • The Journal of Asian Finance, Economics and Business
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    • 제7권4호
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    • pp.121-131
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    • 2020
  • This study aims to investigate the interplay between education and local roads on Foreign Direct Investment (FDI) in the Philippines, using economic growth as an instrument. The study used the quantitative research design applying both descriptive and inferential statistics. A combination of Two Stage Least Square Regression Model and three approaches in Panel Regression Model such as Pooled Least Square, Fixed Effect Model, and Random Effect Model were utilized in order to study the effects of education and local roads on foreign direct investment of the Philippines. Based on Fixed Effect regression results, higher education graduates and local road investments, as conditioned by economic growth, were significant factors in order to increase the foreign direct investment in the Philippines. Accordingly, a unit increase in higher education graduates, as conditioned by economic growth, leads to 8.758 unit increases in the foreign direct investment. While, a unit increased in local road investments, as conditioned by economic growth, leads to a 0.002 decrease in foreign direct investment. The regression results of the study suggest that the Foreign Direct Investment in the regions such as CAR, I, II, IV-B, V, VIII, IX, X, XI, XII, XIII, and ARMM are higher compared to Region IV-A.

지역경제 활성화를 위한 사회적 기업에 관한 탐색적 연구 : 커뮤니티 비즈니스를 중심으로 (An Exploratory Research on the Social Enterprise for Local Economic Activation : Focus on Community Business)

  • 김영수;이광우;권주형
    • 지식경영연구
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    • 제9권1호
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    • pp.77-96
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    • 2008
  • The purpose of this study is to find the new model of successful social enterprise on the basis of local economy and industry in Korea. The trends and definitions of social enterprise were discussed first of all and community business model operated by civilians and members of a community was studied. The community business of local friendly type(LFT) was focused especially. Some factors of LFT are such as the solution of economic polarization and employment aggravation, the recovery of local community, the solution of local problem, and new method of labor contract. As the result of exploratory analysis on community business in Korea, Some distinctive features were showed that the majority of business was managed by local government, the outcomes of local community business were improvement of local income and creation of employment. Also, there were barriers such as finance, marketing, and lack of entrepreneurship. In conclusion, community business enterprise on the basis of local is effective to develop local economy and it should be owned by local civilians. In addition, long-term aims, entrepreneurship, and positiveness need for making of local society wealth.

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Energy and force transition between atoms and continuum in quasicontinuum method

  • Chang, Shu-Wei;Liao, Ying-Pao;Huang, Chang-Wei;Chen, Chuin-Shan
    • Interaction and multiscale mechanics
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    • 제7권1호
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    • pp.543-561
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    • 2014
  • We present a full energy and force formulation of the quasicontinuum method with non-local and local transition elements. Non-local transition elements are developed to transmit inhomogeneity from the atomistic to the continuum regions. Local transition elements are developed to resolve the mathematical mismatch between non-local atoms and the local continuum. The rationale behind these transition elements is provided by analyzing the energy and force transitions between atoms and continuum under the Cauchy-Born rule. We show that breakdown of the Cauchy-Born rule occurs for slaved atoms of local elements within the cutoff of non-local atoms. The inadequacy of the Cauchy-Born rule at the transition region naturally leads to the need of atomistic treatment of transition slaved and transition representative atoms. Such an atomistic treatment together with a full or cutoff sampling allows non-local transition elements containing these transition entities to transmit inhomogeneity. Different force formulations for transition representative atoms and pure local representative atoms allow the local transition elements to resolve non-local and local mismatches. The method presented herein is validated by force calculations in an unstressed perfect crystal as well as an unrelaxed grain boundary model. A nanoindentation simulation in 3D is conducted to demonstrate the accuracy and efficiency of the proposed method.

Effect of high temperatures on local bond-slip behavior between rebars and UHPC

  • Tang, Chao-Wei
    • Structural Engineering and Mechanics
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    • 제81권2호
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    • pp.163-178
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    • 2022
  • This paper aimed to study the local bond-slip behavior between ultra-high-performance concrete (UHPC) and a reinforcing bar after exposure to high temperatures. A series of pull-out tests were carried out on cubic specimens of size 150×150×150 mm with deformed steel bar embedded for a fixed length of three times the diameter of the tested deformed bar. The experimental results of the bond stress-slip relationship were compared with the Euro-International Concrete Committee (CEB-Comite Euro-International du Beton)-International Federation for Prestressing (FIP-Federation Internationale de la Precontrainte) Model Code and with prediction models found in the literature. In addition, based on the test results, an empirical model of the bond stress-slip relationship was proposed. The evaluation and comparison results showed that the modified CEB-FIP Model code 2010 proposed by Aslani and Samali for the local bond stress-slip relationship for UHPC after exposure to high temperatures was more conservative. In contrast, for both room temperature and after exposure to high temperatures, the modified CEB-FIP Model Code 2010 local bond stress-slip model for UHPC proposed in this study was able to predict the test results with reasonable accuracy.