• Title/Summary/Keyword: Bottom-up Model

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A Study on the Ultimate Strength Behavior according to Modeling Range at the Stiffened Plate (선체보강판의 모델링범위에 따른 최종강도거동에 관한 연구)

  • Park Jo-Shin;Ko Jae-Yong
    • Proceedings of KOSOMES biannual meeting
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    • 2004.11a
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    • pp.137-141
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    • 2004
  • Ship structures are basically an assembly of plate elements and the load-carrying capacity or the ultimate strength is one of the most important criteria for safety assessment and economic design. Also, Structural elements making up ship plated structures do not work separately, resulting in high degree of redundancy and complexity, in contrast to those of steel framed structures. To enable the behavior of such structures to be analyzed, simplifications or idealizations must essentially be made considering the accuracy needed and the degree of complexity of the analysis to be used. On this study, to investigate effect of modeling range, the finite element method are used and their results are compared varying the analysis ranges. The model has been selected from bottom panels of large merchant ship structures. For FEA, three types of structural modeling are adopted in terms of the extent of the analysis. The purpose of the present study is to numerically calculate the characteristics of ultimate strength behavior according to the analysis ranges of stiffened panels subject to uniaxial compressive loads.

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Critical Success and Failure Factors of e-Government Project Implementation in Kenya (케냐의 전자정부 프로젝트 핵심 성공 및 실패 요인)

  • Wamoto, Francis O.K.;Hwang, Gee-Hyun
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.2
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    • pp.119-128
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    • 2016
  • Use of ICT in Government has ability to improve service delivery to its citizens, and yet many developing countries have lagged behind in the implementation of e-Government. Many e-Government initiatives also failed to achieve their objectives in developing countries. This paper therefore aims to identify critical failure or success factors in Kenya, using Heeks' Factor Model. A survey questionnaire was developed and data were collected and analyzed from officials and interested citizens. The analysis results enabled to highlight seven specific success and failure factors, and their constituent elements in Kenya. The Kenyan overall e-Government implementation score belongs to the Zone of Improvement (3.52 of total 5.0), which means partial success or failure. The enablers of e-Government projects are good strategy formulation, and internal and external drive, whereas main failures of e-Government are weak ICT infrastructure. The areas for improvement are project management, design, competencies and funding. Data analysis highlights both strengths and weaknesses for each factor or variable. In particular, Kenyan government excels at the drive for change by top to bottom government officers as well as external stakeholders, while the government officers who are using e-Government are satisfied with the availability of vision, strategy and plan of e-Government implementation. Both technologies and e-transactions laws were the worst of all the variables in e-Government implementation. Two areas should be improved using immediate corrective action. In-depth study reveals that government officers and citizens can't fully use their laptop and mobile devices due to the lack of both ICT network and its operating technology, and legal system associated with the transaction of business information. Finally, the study ends up with recommendations for policy makers to shape the future of e-Government system in both developing and developed countries.

Analysis of the Hydraulic Behaviour in the Nearshore Zone by a Numerical Model (수치모형에 의한 연안해역 해수운동의 분석)

  • Lee, Hee-Young;Jeoung, Sun-Kil
    • Water for future
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    • v.27 no.2
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    • pp.73-83
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    • 1994
  • The unproper development of the nearshore zone can enhance the diffusion of pollutant in the nearshore zone resulting in unbalanced sediment budget of beach which causes alteration of beach topography. Therefore, it is required to predict the effects of the envirnmental change quantitatively. In this paper, the depth-averaged and time-averaged energy balance equation is selected to acount for the wave transformation such as refraction, shoaling effect, the surf zone energy disipation, wave breaking index and bore, due to wave breaking in the shore region.(Numerical solutions are obtained by a finite difference method, ADI and Upwind. For the calculation of the wave-induced current, the unsteady nonlinear depth-averaged and time-averaged governing equation is derived based on the continuity and momentum equation for imcompressible fluid.) Numerical solutions are obtained by finite difference method considering influences of factors such as lateral mixing coefficient, bed shear stress, wave direction angle, wave steepness, wave period and bottom slope. The model is applied to the computation of wave transformation, wave-induced current and variation of mean water leel on a uniformly sloping beach.

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An Exploratory Study on 'Smart Citizens Party' Model ('스마트시민정당' 모델에 관한 탐색적 연구)

  • Noh, Kyoo-Sung;Kim, Hyeong-Soo
    • Journal of Digital Convergence
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    • v.9 no.1
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    • pp.125-136
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    • 2011
  • This article is exploring the possibility of establishment of a 'Smart Citizens Party'. In the society based the social computing, the individual leads the technical progress and the society which is adapted for this circumstance is changing in the direction of user-centric. Also, in the political process, we can see this social phenomenon. In other words, there's a quite possibility that decision-making structure may shift from the top-down approach to the bottom-up approach by the networked individuals or flexible voluntary group. In this context, this paper will propose the 'Smart Citizens Party' model that accept the change of political and social environment due to the advent of the social computing and cope with this change. The 'Smart Citizens Party' means the 'Party for Smartizen' of this social computing era. The 'Smart Citizens Party' is the intermediate party that link the political party to the civil society and is smart citizen's party that is operated democratically by active participation of citizens. This paper will review on structure and operational issues of political parties in Korea and study future-oriented solution and/or way to discovered problems of political parties in Korea.

Commitment to Global Open Access Transition Collaboration: Outcomes and Lessons from SCOAP3-Korea

  • Jung, Youngim;Kim, Hwanmin
    • Journal of Information Science Theory and Practice
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    • v.10 no.spc
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    • pp.46-55
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    • 2022
  • Eight years have passed since the Sponsoring Consortium for Open Access Publishing in Particle Physics (SCOAP3) was launched. SCOAP3 is one of the most successful global partnerships and funds for Open Access and has been benchmarked by other Open Access initiatives. The Korea Institute of Science and Technology Information (KISTI) joined as the first Asian partner in 2011, and has supported its shared vision and contributed its financial commitment since the beginning of SCOAP3. SCOAP3-Korea is the first bottom-up collaboration for local libraries to re-direct funds previously used for subscriptions to Open Access publishing. This paper explores the roles and responsibilities of KISTI in the Open Access quest. It describes the commitment to SCOAP3 in South Korea, including how the collaboration model for SCOAP3-Korea differs from the global model. This paper also discusses the impact of SCOAP3-Korea by analyzing publications affiliated by Korean authors in SCOAP3 journals for the last six years (2014-2019). We have integrated the national R&D project and research outcome data from NTIS (National Science and Technology Information Service) to investigate the research articles benefited by SCOAP3 and research publications in non-SCOAP3 journals. The positive impact of SCOAP3 in increasing research publication in the discipline was revealed compared to non-SCOAP3 journals. In addition, the financial benefit of SCOAP3-Korea has been proven. With regard to the investment for readers, $137,094 USD was saved during the SCOAP3 Phase 1 and 2, while $748,923 USD was saved with regard to publication fees. We discussed the lessons from SCOAP3-Korea for commitment to a larger-scale Open Access transition.

Gas Explosion Hazard Analysis in Domestic (가정집에서 가스폭발 위험성 분석)

  • Jo Young-Do;Kim Ji-Yun;Kim Sang-sub
    • Journal of the Korean Institute of Gas
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    • v.5 no.2 s.14
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    • pp.36-42
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    • 2001
  • A leak of fuel gas in partially confined area creates a flammable atmosphere and give rise to an explosion, which is one of the most common accident in domestic. Observations from accident in domestic suggest that some explosions are caused by a quantify of fuel significantly less than lower explosion limit(LEL) amount required to fill the room, which is attributed to inhomogeneous mixing of leaked gas. The minimum amount of leaked gas for explosion is highly dependent on the mixing degree in the area. For lighter gas, such as methane, a high concentration tends to build up in the space from ceiling of room. But heavy gas, such as propane, a high concentration tends to build up in the space from bottom of room. This paper presents a method for analysing the explosion hazard in a room with very small amount of leaked gas. Based on explosion limit concentration, the gaussian distribution model is used to estimate the minimum amount of leak which yields a specified explosion pressure. The results demonstrate that catastrophic structural damage can be achieved with a volume of fuel gas which is less than 0.5 percent of the total enclosed volume in domestic. The method will help analyzing hazard to develop new safe device as well as investigating accident.

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Prediction of Water-Quality Enhancement Effects of Gates Operation in the West-Nakdong River Using RMA2/RMA4 Models (RMA2/RMA4 모형을 이용한 서낙동간 수문연계운영의 수질개선 효과 예측)

  • Lee, Keum-Chan;Yoon, Young-Sam;Lee, Nam-Joo
    • Journal of Environmental Science International
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    • v.18 no.9
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    • pp.971-981
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    • 2009
  • An objective of this study is as follows: 1) performing sensitivity analysis and parameter estimation of RMA2 and RMA4 models for the West-Nakdong River, 2) drawing up alternatives of gates-operation for water-quality enhancement, and 3) quantitative evaluation of methodology of 'flow-restoration by gates-operation' among 'Comprehensive Plan Improving Water-Quality in the West-Nakdong River(WNR)' with the target water-quality(BOD at Nakbon-N point: below 4.3 mg/L). The parameters for the RMA2 (depth-averaged two-dimensional flow model) and RMA4 (depth-averaged two-dimensional water-quality model) were determined by sensitivity analysis. Result of parameter estimation for RMA2 and RMA4 models is $1,000\;Pa{\cdot}s$ of the eddy viscosity, 20 of the Peclet number, 0.025 of the Manning coefficient, and $1.0\;m^2/s$ of the diffusion coefficient. We have evaluated the effects of water-quality enhancement of the selected alternatives by numerical simulation technique with the models under the steady-state flow condition and the time-variant transport condition. Because of no-resuspension from river bottom and considering BOD as conservative matter, these simulation results slightly differ from real phenomena. In the case of $50\;m^3/s$ of Daejeo-gate inflow, two-dimensional flow pn results result represents that small velocity occurs in the Pyungkang Stream and no flow in the Maekdo River. In the WNR, there occurs the most rapid flow near timhae-bridge. In the WNR, changes of water-quality for the four selected simulation cases(6, 10, 30, $50\;m^3/s$ of the Daejeo-gate inflow) were predicted. Since the Daejeo-Gate and the Noksan-Gate can be opened up to 7 days, it would be found that sustainable inflow of $30\;m^3/s$ at the Daejeo-gate makes BOD in the WNR to be under the target of water-quality.

The Living Lab Model of Smart City Based on Citizen Participation (시민참여 기반의 스마트시티 리빙랩 모델 설정)

  • Choi, Min-Ju;Lee, Sang-Ho;Jo, Sung-Su;Jung, Yae-Jin;Jo, Sung-Woon
    • The Journal of the Korea Contents Association
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    • v.20 no.4
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    • pp.284-294
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    • 2020
  • As a solution to local and social problems, the active use of smart city living labs is becoming increasingly important. The answer to solving local and social problems lies in the citizen and the field. The purpose of this study is to establish a smart city living lab model based on citizen participation. In this study, smart city living lab model(4P-SCLLM) based on citizen participation was established through domestic and overseas living lab methodology and case analysis. In order to evaluate the systemicity and specificity of the 4P-SCLLM, a smart city living lab model, we recently compared it with the living lab process in Busan where smart city living lab is applied. As a result of analyzing, the analysis shows similar trends in each stage, and Busan's private sector showed a similar process to 4P-SCLLM On the other hand, public and private sector cooperation and support systems were found to be less than the 4P-SCLLM model And In technology and methodology, the 4P-SCLLM model is analyzed to have a living lab process that incorporates new technologies. In order to maintain the 4P-SCLLM continuously, first, participants and stakeholders need to participate actively and communicate while collaborating on the whole process from start to finish. Second, public awareness needs to be improved. Third, continuous citizenship verification of services is needed. Fourth, citizens' constant participation is needed. Through these implications, this study proposed 4P-SCLLM as a smart city living lab model suitable for the domestic situation.

Automatic Extraction of Abstract Components for supporting Model-driven Development of Components (모델기반 컴포넌트 개발방법론의 지원을 위한 추상컴포넌트 자동 추출기법)

  • Yun, Sang Kwon;Park, Min Gyu;Choi, Yunja
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.8
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    • pp.543-554
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    • 2013
  • Model-Driven Development(MDD) helps developers verify requirements and design issues of a software system in the early stage of development process by taking advantage of a software model which is the most highly abstracted form of a software system. In practice, however, many software systems have been developed through a code-centric method that builds a software system bottom-up rather than top-down. So, without support of appropriate tools, it is not easy to introduce MDD to real development process. Although there are many researches about extracting a model from code to help developers introduce MDD to code-centrically developed system, most of them only extracted base-level models. However, using concept of abstract component one can continuously extract higher level model from base-level model. In this paper we propose a practical method for automatic extraction of base level abstract component from source code, which is the first stage of continuous extraction process of abstract component, and validate the method by implementing an extraction tool based on the method. Target code chosen is the source code of TinyOS, an operating system for wireless sensor networks. The tool is applied to the source code of TinyOS, written in nesC language.

The Development and Validation of Learning Progression for Solar System Structure Using Multi-tiers Supply Form Items (다층 서답형 문항을 이용한 태양계 구조 학습 발달과정 개발 및 타당성 검증)

  • Oh, Hyunseok;Lee, Kiyoung
    • Journal of the Korean earth science society
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    • v.41 no.3
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    • pp.291-306
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    • 2020
  • In this study, we developed a learning progression for the structure of the solar system using multi-tier supply form items and validated its appropriateness. To this end, by applying Wilson's (2005) construct modeling approach, we set up 'solar system components,' 'size and distance pattern of solar system planets,' and 'solar system modeling' as the progress variables of the learning progression and constructed multi-tier supply form items for each of these variables. The items were applied to 150 fifth graders before and after the classes that dealt with the 'solar system and star' unit. To describe the results of the assessment, the students' responses to each item were categorized into five levels. By analyzing the Wright map that was created by applying the partial credit Rasch model, we validated the appropriateness of the learning progression based on the students' responses. In addition, the validity of the hypothetical pathway that was established in the learning progression was verified by tracking changes in the developmental level of students before and after the classes. The results of the research are as follows. The bottom-up research method that used multi-tier supply form items was able to elaborately set the empirical learning progression for the conceptualization of the structure of the solar system that is taught in elementary school. In addition, the validity of the learning progression was high, and the development of students was found to change with the learning progression.