• Title/Summary/Keyword: Bottom-up approach

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Analysis of Sedimentation Around Jetties in the West Coast: based on field measurement and hydrodynamic modeling (서해연안 돌제구조물 주위의 침퇴적 해석: 실측 및 수동역학 모델에 의한 초기추정)

  • Suh, Seung-Won;Yoo, Gyeong-Sun;Lee, Hwa-Young
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.4
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    • pp.345-354
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    • 2007
  • A sedimentation analysis has been attempted to figure out sedimentation environment due to construction of coastal jetties, such as fish harbor dike, flow guided dike and jetty in shallow Kusipo area, in which tidal range marks up to 6.6 meters in spring tide. As an initial approach of understanding field measurement were done on several stations along reference lines with total station and photo analysis taken by remote controlled small air craft far one and half years. Also numerical tests were done by 2-D ADCIRC model considering dry-wet treatment to evaluate flow and bottom shear stress variations. According to direct measurement, deposition seems to be dominant on Kusipo beach. Model results show bottom shear stress lessens to $0.10{\sim}0.15\;N/m^2$ on most shadow zone of jetties and the inner zone is suffering sedimentation as a result of dike construction. However this is the first approach with limited analysis, thus it should be dealt further considering physical characteristics of bottom sediments in a complete sediment model on upcoming study.

A study on the method for the Integrated Cost Estimate based on Project(ICEP) of program management with typical model (기준모델을 사용한 종합사업관리용역비 산정방법(ICEP) 연구)

  • Baek, Myeongchang;Park, Junmo;Park, Gilbeom;Kim, Okkyue
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.1
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    • pp.119-128
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    • 2015
  • Domestic dominant method in subcontract cost estimate for comprehensive program management is estimation by referencing similar cases or relying on the experience and expertise of the engaged. However, this method is not reliable due to lack of accuracy, making it harder for clients to plan and budget the program. Since budget itself is roughly estimated, it becomes a source of cost rise in the course of management due to design modifications. Therefore, the client and service providers shall calculate more accurate service cost by applying objective and scientific method in order to minimize cost rise and cost related dispute. Traditional cases, in estimating program management cost, took Top-Down approach based on precedents and experience. On the contrary, this study will categorize management structure into phases and activities, issue WBS for each phase to estimated schedule and cost for each code, and take Bottom-UP approach. By taking this approach named ICEP (Integrated Cost Estimate based on Project), Set project typical model will be developed for service cost estimating, calculate cost by applying project-specific factors. Also, by analyzing progress data and allocated management cost to complement them, more efficient construction management will take shape based on program management cost standards which reflect project-specific features.

The Economic Benefit of the R&D Performance from Government-funded Research Institute for Science and Technology: Evidence from K Research Institute (과학기술계 정부출연연구기관 연구개발 성과의 경제적 편익 추정에 관한 연구 : K연구원의 사례를 중심으로)

  • Kwak, Kiho
    • Journal of Korea Technology Innovation Society
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    • v.20 no.4
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    • pp.1122-1158
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    • 2017
  • Government-funded research institutes in the field of science and technology of Korea have contributed to the growth of the national economy and industrial development since the 1960s. However, those institutes recently have faced with criticism over the R&D performance on investment. Accordingly, we suggest two analytical approaches that estimate the economic benefit of the R&D performance of those institutes, (1) 'bottom-up' approach that aggregates the economic benefits of individual performances, e.g., technology transfer, technology support for small and medium enterprises, and the supply of researcher manpower and (2) 'top-down' one that estimates the contribution of those institutes on the economic growth of the industries that the R&D performance of those institutes is mainly utilized. In addition, by applying two approaches, we computed the economic benefit of the performance of the K institute in the 1996-2014 periods at 12.3 trillion won and 29.5 trillion won, respectively. Lastly, we suggest the feasibility of two approaches from the perspective of complementarity. Our study provides analytical approaches that estimate the economic benefit of the R&D performance from government funded research institutes in Korea. Lastly, our study contributes to the understanding of public on science and technology as well as the enhancement of legitimacy on those institutes among the public.

A Cooperative Workflow Modeling Methodology Using Fragment-ICNs (조각-ICN 기반 협업 워크플로우 모델링 방법론)

  • Kim Hyung-Mok;Kim Kwang-Hoon
    • Journal of Internet Computing and Services
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    • v.6 no.6
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    • pp.107-115
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    • 2005
  • A workflow procedure has recently become more complicated and large scaled. In this paper, we propose an advanced workflow modeling methodology, called a fragment driven cooperative workflow modeling methodology. which enables several real workflow designers to cooperatively define a workflow model. The methodology is a Bottom-Up approach in terms of integrating a set of fragment ICNs to compose a complete workflow model. Each fragment ICN is defined by each participant in the cooperative modeling session, We also use the ICN based formal description and the ICN based graphical notation as well. Finally, we prove the feasibility of the methodology by implementing a cooperative workflow modeling system.

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A SIMULINK Modeling for a Fractional-N Frequency Synthesizer (SIMULINK를 이용한 Fractional-N 주파수합성기의 모델링 기법)

  • Kim, In-Jeong;Seo, Woo-Hyong;Ahn, Jin-Oh;Kim, Dae-Jeong
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.4
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    • pp.103-109
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    • 2007
  • This paper presents behavioral models using SIMULINK and Verilog-a for a PLL based fractional-N frequency synthesizer. By adopting a top-down approach along with the traditional bottom-up transistor level design in parallel, the design time is greatly shortened, and a co-verification method for both the digital and the analog part is considered. Under this consideration, the SIMULINK modeling reduces simulation time and easily estimates the PLL's performance on the top level. Verilog-a is able to verify the feasibility of each blocks at first hand because it is compatible with transister level circuits. Then, an efficient way of the design is presented by comparing the results of both models.

Analysis of Defense Communication-Electronics Technologies using Data Mining Technique (데이터 마이닝 기법을 이용한 군 통신·전자 분야 기술 분석)

  • Baek, Seong-Ho;Kang, Seok-Joong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.6
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    • pp.687-699
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    • 2020
  • The government-led top-down development approach for weapons system faces the problem of technological obsolescence now that technology has rapidly grown. As a result, the government has gradually expanded the corporate-led bottom-up project implementation method to the defense industry. The key success factor of the bottom-up project implementation is the ability of defense companies to plan their technologies. This paper presented a method of analyzing patent data through data mining technique so that domestic defense companies can utilize it for technology planning activities. The main content is to propose corporate selection techniques corresponding to the defense communication-electronics sectors and conduct principal component analysis and cluster analysis for the International Patent Classification. Through this, the technology was classified into four groups based on the patents of nine companies and the representative enterprises of each group were derived.

Backward estimation of precipitation from high spatial resolution SAR Sentinel-1 soil moisture: a case study for central South Korea

  • Nguyen, Hoang Hai;Han, Byungjoo;Oh, Yeontaek;Jung, Woosung;Shin, Daeyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.329-329
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    • 2022
  • Accurate characterization of terrestrial precipitation variation from high spatial resolution satellite sensors is beneficial for urban hydrology and microscale agriculture modeling, as well as natural disasters (e.g., urban flooding) early warning. However, the widely-used top-down approach for precipitation retrieval from microwave satellites is limited in several hydrological and agricultural applications due to their coarse spatial resolution. In this research, we aim to apply a novel bottom-up method, the parameterized SM2RAIN, where precipitation can be estimated from soil moisture signals based on an inversion of water balance model, to generate high spatial resolution terrestrial precipitation estimates at 0.01º grid (roughly 1-km) from the C-band SAR Sentinel-1. This product was then tested against a common reanalysis-based precipitation data and a domestic rain gauge network from the Korean Meteorological Administration (KMA) over central South Korea, since a clear difference between climatic types (coasts and mainlands) and land covers (croplands and mixed forests) was reported in this area. The results showed that seasonal precipitation variability strongly affected the SM2RAIN performances, and the product derived from separated parameters (rainy and non-rainy seasons) outperformed that estimated considering the entire year. In addition, the product retrieved over the mainland mixed forest region showed slightly superior performance compared to that over the coastal cropland region, suggesting that the 6-day time resolution of S1 data is suitable for capturing the stable precipitation pattern in mainland mixed forests rather than the highly variable precipitation pattern in coastal croplands. Future studies suggest comparing this product to the traditional top-down products, as well as evaluating their integration for enhancing high spatial resolution precipitation over entire South Korea.

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Reconstruction of the Experience of Single Mothers in Poverty -The Meaning of Self-Sufficiency, Welfare Dependency, and Work- (빈곤 여성 한부모 자활 경험의 재구성 -자활, 복지의존, 일의 의미-)

  • Chong, Hye-Suk
    • Korean Journal of Social Welfare
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    • v.67 no.4
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    • pp.251-277
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    • 2015
  • This qualitative study is designed for the reconstruction of the experience of single mothers in poverty based on the bottom-up approach. Welfare dependency is identified as vital help to protect their own and children's lives, through their stories telling that welfare services provided by government and community take care of them "in place of their husbands", and "raise them up by hand." What is self-sufficiency to them is more of a process-orientation through welfare dependency than a state out of it, and a way to look through building their self-esteem and working to discover their self-worth except their economic power. Restoring their potential to self-sufficiency through dealing with their psycho-social stresses and expanding services for them related to child-care(education) and occupation ability development for long-term self-sufficiency, rather than hasty focusing on welfare exit, should be built on the foundation of helping them self-sufficient. In order for the self-sufficiency program to overcome the participant's images of "subordination and stigma" and to convey the original meaning of "welfare to work", the performance and evaluation system of self-sufficiency programs that reflects the insider's perspectives on their participation motive and process, and the self-sufficiency program customized for their needs and interests should be encouraged to develop.

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PBFiltering: An Energy Efficient Skyline Query Processing Method using Priority-based Bottom-up Filtering in Wireless Sensor Networks (PBFiltering: 무선 센서 네트워크에서 우선순위 기반 상향식 필터링을 이용한 에너지 효율적인 스카이라인 질의 처리 기법)

  • Seong, Dong-Ook;Park, Jun-Ho;Kim, Hak-Sin;Park, Hyoung-Soon;Roh, Kyu-Jong;Yeo, Myung-Ho;Yoo, Jae-Soo
    • Journal of KIISE:Databases
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    • v.36 no.6
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    • pp.476-485
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    • 2009
  • In sensor networks, many methods have been proposed to process in-network aggregation effectively. Unlike general aggregation queries, skyline query processing compares multi-dimensional data for the result. Therefore, it is very difficult to process the skyline queries in sensor networks. It is important to filter unnecessary data for energy-efficient skyline query processing. Existing approach like MFTAC restricts unnecessary data transitions by deploying filters to whole sensors. However, network lifetime is reduced by energy consumption for many false positive data and filters transmission. In this paper, we propose a bottom up filtering-based skyline query processing algorithm of in-network for reducing energy consumption by filters transmission and a PBFiltering technique for improving performance of filtering. The proposed algorithm creates the skyline filter table (SFT) in the data gathering process which sends from sensor nodes to the base station and filters out unnecessary transmissions using it. The experimental results show that our algorithm reduces false positives and improves the network lifetime over the existing method.

A Study on Estimating Ship's Emission in the Port Area of Mokpo Port (목포항 항만구역 내 선박 배기가스 배출량 산정에 대한 연구)

  • Bui, Hai-Dang;Kim, Hwayoung
    • Journal of Korea Port Economic Association
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    • v.39 no.3
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    • pp.47-60
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    • 2023
  • A thorough inventory of ship emissions, particularly ship's emission of in-port area is necessary to identify significant sources of exhaust gases such as NOx, SOx, PM, and CO2 and trends in emission levels over time, and reduce their serious effects on the environment and human health. Therefore, the goal of this study is to assess the volume of emissions from ships in Mokpo port, which serves as a gateway to the southwest coast of Korea, using a bottom-up methodology and data from the automatic identification system (AIS) and the Korean Port Management Information System (Port-MIS). In this work, an analysis of ship movement utilizing AIS data and an actual set of data on ship specification were gathered. By examining ship movement using AIS data, We also proposed a new approach for identifying cruising/maneuvering mode. Finally, the results were classified by ship operating mode, by exhaust gas, by ship type, and by berth, which provides a thorough and in-depth analysis of the air pollution caused by ships in Mokpo port.