• Title/Summary/Keyword: global solution

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Optimal Design Of Multisite Batch-Storage Network under Scenario Based Demand Uncertainty (다수의 공장을 포함하는 불확실한 수요예측하의 회분식 공정-저장조 망의 최적설계)

  • 이경범;이의수;이인범
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.6
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    • pp.537-544
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    • 2004
  • An effective methodology is reported for determining the optimal lot size of batch processing and storage networks which include uncertain demand forecasting. We assume that any given storage unit can store one material type which can be purchased from suppliers, internally produced, infernally consumed, transported to or from other sites and/or sold to customers. We further assume that a storage unit is connected to all processing and transportation stages that consume/produce or move the material to which that storage unit is dedicated. Each processing stage transforms a set of feedstock materials or intermediates into a set of products with constant conversion factors. A batch transportation process can transfer one material or multiple materials at once between sites. The objective for optimization is to minimize the probability averaged total cost composed of raw material procurement, processing setup, transportation setup and inventory holding costs as well as the capital costs of processing stages and storage units. A novel production and inventory analysis formulation, the PSW(Periodic Square Wave) model, provides useful expressions for the upper/lower bounds and average level of the storage inventory. The expressions for the Kuhn-Tucker conditions of the optimization problem can be reduced to two sub-problems. The first yields analytical solutions for determining lot sires while the second is a separable concave minimization network flow subproblem whose solution yields the average material flow rates through the networks for the given demand forecast scenario. The result of this study will contribute to the optimal design and operation of the global supply chain.

Development 2.0: Principles and Warnings for Leveraging Advances in Information Communication Technologies for Improved Development Efforts

  • Kang, Christina Soyeon;Lal, Bhavya
    • STI Policy Review
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    • v.1 no.3
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    • pp.25-37
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    • 2010
  • Advances in Information Communication Technologies (ICT) have demonstrated tremendous potential for solving development challenges and improving development processes, culminating in the new Development 2.0. Many development practitioners have embraced ICT (particularly on Web 2.0 and mobile phone technologies and applications), which have become hot topics in both the development community and the policy community as they engage in development practice and dialogue. Despite this excitement, there lacks among the policy community a robust understanding of the powers and pitfalls of ICT in development, executed actions to back the excited chatter, and dissemination of this understanding to practitioners and policymakers alike. We conducted a literature review, interviewed experts, and engaged in discussion with leaders in international development and science and technology policy to provide an operational framework base in which to view ICT in development. This framework regards ICT as tools that support more effective and efficient community development actions and appropriate consideration of general guidelines, which enable better engagement across and within sectors and individuals. Flexibility and accountability are critical requirements pervading throughout the various actions and guidelines, which promote transparent, partnership-based, and sustainable development. We highlight the strengths and weaknesses of ICT to focus on the cautions to keep ICT access and distribution in context, understand the various levels of technologies and services, and dig below the surface as excitement about ICT increases and threatens to become a short-term solution. We offer ideas for specific programs that policymakers can implement to contribute to a more efficient and effective development process to ultimately support global human development, but stress the endless possibilities that can be explored with creativity and flexibility beyond what is proposed here.

Efficient Dynamic Time Warping Using 2nd Derivative Operator (2차 미분 연산자를 이용한 효과적인 Dynamic Time Warping)

  • Kim, Se-Hoon;Choi, Hyung-Il;Rhee, Yang-Won;Jang, Seok-Woo
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.2
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    • pp.61-69
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    • 2011
  • Dynamic Time Warping based on Dynamic Programming is the one of the most widely been used to compare the similarity of two patterns. DTW algorithm has two known problems. The one is singularities. And the another problem is the accuracy of the warping path with patterns. Therefore, this paper suggest the solution for DTW algorithm to use a 2nd derivative operator. Laplacian of Gaussian is a kind of a 2nd derivative operator. Consequently, our suggestion method to apply to this operator, more efficient to solve the singularities problems and to secure a accuracy of the warping path. And the result shows a superior ability of this suggested method.

The Effect of Data 3 on the Utilization of Medical Big Data for Early Detection of Dementia (데이터 3법이 치매 조기 예측을 위한 의료 빅데이터 활용에 미치는 영향 연구)

  • Kim, Hyejin
    • Journal of Digital Convergence
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    • v.18 no.5
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    • pp.305-315
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    • 2020
  • As the incidence and prevalence of dementia increases with our aging population, so does the social burden on our society, which calls for a special emphasis on need for early diagnosis. Thus, efforts are made to prevent dementia and early detection but with current diagnostic measures, these efforts appear futile. As a solution, it is crucial to integrate and standardize healthcare big data and analysis of each index. In order to increase use of large database, the Korea National Assembly passed the Data 3 Act focusing on open-access and sharing of database, but a follow-up legislation is needed a for safer utilization. In this study, we have identified number of foreign of foreign policies through review of prior researches on the topic leading to specific enforcement ordinances tailored to the Data 3 Act for safe access and utilization of database. We also aimed to establish secure process of data collection and disposal as well as governance at the national level to ensure safe utilization of healthcare big data.

A Study on the Structural Problems and Global Development Model and Policy of the Distant-water Fisheries, Korea (원양어업의 경영구조적 문제와 글로벌 발전모델 및 정책에 관한 연구)

  • Lee, Sang-Go
    • Journal of Fisheries and Marine Sciences Education
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    • v.18 no.2
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    • pp.85-97
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    • 2006
  • With extension of national jurisdiction over coastal living resources, new dimensions and objectives should be added to international cooperation in distant-water fisheries concepts. For distant-water fishing nations, Korea, joint exploitation of these resources is today considered not only as a way of producing additional income opportunities, but first of all as at least a partial solution to neutralization of harvesting limitations imposed on them in traditionally exploited fishing grounds.This paper explores the development of Korean distant-water fisheries agreements and reviews the various types of agreements currently in place and discusses the future of Korean distant-water fisheries agreements with third countries. The relationship between coastal States and fishing fleets from non-adjacent countries has been transformed since the 1980s. This was primarily a result of the declaration of Exclusive Economic Zones(EEZs) by many coastal states in the years leading up to the close of the negotiations of the UNCLOS in 1982. Significantly, by recognizing the right of coastal states to determine how their waters were to be exploited, UNCLOS provided a legal basis and economic motivation for the negotiation of access agreements between coastal states and distant-water fishing nations, KoreaThere is a real danger that Korean distant-water fisheries agreements could and do result in the adverse environmental impacts experienced in Korean coastal waters being transferred to third country water and consequently creating socio-economic problems for these third countries. Korean distant-water fisheries agreements with third countries have the potential to be a force for good if they are well managed and if the principals that will be applied within Korean coastal waters, through the reform of the distant-water fisheries policy, are applied equally upon third country waters.

Phenotypic and genotypic screening of rice accessions for salt tolerance

  • Reddy, Inja Naga Bheema Lingeswar;Kim, Sung-Mi;Yoon, In Sun;Kim, Beom-Gi;Kwon, Taek-Ryoun
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.188-188
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    • 2017
  • Rice (Oryza sativa L.) is one of the major crops that is seriously impacted by global soil salinization. Rice is among those crops where most of the high-yielding cultivars are highly sensitive to salinity. The key to a plant survival under NaCl salt stress is by maintaining a high $K^+/Na^+$ ratio in its cells. Selection for salinity tolerance genotypes of rice based on phenotypic performance alone is less reliable and will delay in progress in breeding. Recent advent of molecular markers, microsatellites or simple sequence repeats (SSRs) were used to find out salt tolerant rice genotypes. In the current experiment phenotyping and genotyping studies were correlated to differentiate different rice accessions for salinity tolerance. Eight rice accessions along with check plant Dongjin were screened by physiological studies using Yoshida solution with 50mM NaCl stress condition. The physiology studies identified four tolerant and four susceptible accessions based on their potassium concentration, sodium concentration, $K^+/Na^+$ ratio and biomass. 17 SSR markers were used to evaluate these rice accessions for salt tolerance out of which five molecular markers were able to discriminate tolerant accessions from the susceptible accessions. Banding pattern of the accessions was scored comparing to the banding pattern of Dongjin. The study identifies accessions based on their association of $K^+/Na^+$ ratio with molecular markers which is very reliable. These markers identified can play a significant role in screening large set of rice accessions for salt tolerance; these markers can be utilized to improve salt tolerance of commercial rice varieties with marker-assisted selection (MAS) approach.

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Introducing Network Situation Awareness into Software Defined Wireless Networks

  • Zhao, Xing;Lei, Tao;Lu, Zhaoming;Wen, Xiangming;Jiang, Shan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.3
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    • pp.1063-1082
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    • 2018
  • The concept of SDN (Software Defined Networking) endows the network with programmability and significantly improves the flexibility and extensibility of networks. Currently a plenty of research works on introducing SDN into wireless networks. Most of them focus on the innovation of the SDN based architectures but few consider how to realize the global perception of the network through the controller. In order to address this problem, a software defined carrier grade Wi-Fi framework called SWAN, is proposed firstly. Then based on the proposed SWAN architecture, a blueprint of introducing the traditional NSA (Network Situation Awareness) into SWAN is proposed and described in detail. Through perceiving various network data by a decentralized architecture and making comprehension and prediction on the perceived data, the proposed blueprint endows the controllers with the capability to aware of the current network situation and predict the near future situation. Meanwhile, the extensibility of the proposed blueprint makes it a universal solution for software defined wireless networks SDWNs rather than just for one case. Then we further research one typical use case of proposed NSA blueprint: network performance awareness (NPA). The subsequent comparison with other methods and result analysis not only well prove the effectiveness of proposed NPA but further provide a strong proof of the feasibility of proposed NSA blueprint.

Design of an Optimal Controller with Neural Networks for Nonminimum Phase Systems (신경 회로망을 이용한 비최소 위상 시스템의 최적 제어기 설계)

  • 박상봉;박철훈
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.35C no.6
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    • pp.56-66
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    • 1998
  • This paper investigates a neuro-controller combined in parallel with a conventional linear controller of PID type in order to control nonminimum phase systems more efficiently. The objective is to minimize overall position errors as well as to maintain small undershooting. A costfunction is proposed with two conflict objectives. The neuro-controller is trained off-line with evolutionary programming(EP) in such a way that it becomes optimal by minimizing the given cost function through global evaluation based on desired control performance during the whole training time interval. However, it is not easy to find an optimal solution which satisfies individual objective simultaneously. With the concept of Pareto optimality and EP, we train the proposed controller more effectively and obtain a valuable set of optimal solutions. Simulation results show the efficacy of the proposed controller in a viewpoint of improvement of performance of a step response like fast settling time and small undershoot or overshoot compared with that of a conventional linear controller.

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Effect of Rhodophyta extracts on in vitro ruminal fermentation characteristics, methanogenesis and microbial populations

  • Lee, Shin Ja;Shin, Nyeon Hak;Jeong, Jin Suk;Kim, Eun Tae;Lee, Su Kyoung;Lee, Sung Sill
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.1
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    • pp.54-62
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    • 2018
  • Objective: Due to the threat of global warming, the livestock industry is increasingly interested in exploring how feed additives may reduce anthropogenic greenhouse gas emissions, especially from ruminants. This study investigated the effect of Rhodophyta supplemented bovine diets on in vitro rumen fermentation and rumen microbial diversity. Methods: Cannulated Holstein cows were used as rumen fluid donors. Rumen fluid:buffer (1:2; 15 mL) solution was incubated for up to 72 h in six treatments: a control (timothy hay only), along with substrates containing 5% extracts from five Rhodophyta species (Grateloupia lanceolata [Okamura] Kawaguchi, Hypnea japonica Tanaka, Pterocladia capillacea [Gmelin] Bornet, Chondria crassicaulis Harvey, or Gelidium amansii [Lam.] Lamouroux). Results: Compared with control, Rhodophyta extracts increased cumulative gas production after 24 and 72 h (p = 0.0297 and p = 0.0047). The extracts reduced methane emission at 12 and 24 h (p<0.05). In particular, real-time polymerase chain reaction analysis indicated that at 24 h, ciliate-associated methanogens, Ruminococcus albus and Ruminococcus flavefaciens decreased at 24 h (p = 0.0002, p<0.0001, and p<0.0001), while Fibrobacter succinogenes (F. succinogenes) increased (p = 0.0004). Additionally, Rhodophyta extracts improved acetate concentration at 12 and 24 h (p = 0.0766 and p = 0.0132), as well as acetate/propionate (A/P) ratio at 6 and 12 h (p = 0.0106 and p = 0.0278). Conclusion: Rhodophyta extracts are a viable additive that can improve ruminant growth performance (higher total gas production, lower A/P ratio) and methane abatement (less ciliateassociated methanogens, Ruminococcus albus and Ruminococcus flavefaciens and more F. succinogenes.

GA-based parameter identification of DC motors (DC 모터의 GA 기반 파라미터 추정)

  • Lee, Yun-Hyung;So, Myung-Ok
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.6
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    • pp.716-722
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    • 2014
  • In order to design the speed controller of the DC motor system, firstly, parameters estimation of the system must be preceded. In this paper, we proposed the application of genetic algorithm(GA) optimization in estimating the parameters of DC motor. Estimated models are considered both first and second order models, and each estimated model is optimized by minimizing three different types of the evaluation function of GA. Also, GA is imported in comparison with estimation result of numerical analysis method because of its power in searching entire solution space with more probability of finding the global optimum. Data for parameter estimation is acquired from input and output signals of the actual experiment device and the butterworth filter also designs for removing noise in the signals. Finally comparison between real data of the actual device and estimated models is presented to indicate effectiveness and resolution of proposed identification method.