• 제목/요약/키워드: Convergence and integration time

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비정렬 격자계에서 고차 정확도의 내재적 불연속 갤러킨 기법의 개발 (DEVELOPMENT OF AN HIGH-ORDER IMPLICIT DISCONTINUOUS GALERKIN METHOD ON UNSTRUCTURED MESHES)

  • 이희동;권오준
    • 한국전산유체공학회지
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    • 제12권3호
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    • pp.29-40
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    • 2007
  • An implicit discontinuous Galerkin method for the two-dimensional Euler equations was developed on unstructured triangular meshes. The method can achieve high-order spatial accuracy by using hierachical basis functions based on Legendre polynomials. Numerical tests were conducted to estimate the convergence order of numerical solutions to the Ringleb flow and the supersonic vortex flow for which analytic solutions are available. Also, the flows around a 2-D circular cylinder and an NACA0012 airfoil were numerically simulated. The numerical results showed that the implicit discontinuous Galerkin methods couples with a high-order representation of curved solid boundaries can be an efficient method to obtain very accurate numerical solutions on unstructured meshes.

통합 수질계측 시스템 개발 (A development of integrated water-quality measurement system)

  • 양근호
    • 융합신호처리학회논문지
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    • 제8권3호
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    • pp.211-216
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    • 2007
  • 대형 정수장에서 개인수도꼭지까지 전체 급수 설비에서 수질은 반드시 먹는 물 수질기준을 만족해야 한다. 그러나 현재까지도 수돗물의 공급과정은 과학적으로 모니터링 되거나 관리되지 못하고 있다. 수돗물 특히 대부분의 작은 규모의 정수장은 항상 다양한 오염원 및 불순물 등에 노출되어 있다. 최근 일부 대형 정수장이나 배수지 등에 수질감시 시스템이 사용되고 있다. 특히 인터넷을 이용한 수질 모니터링 방법이 일부 지방자치단체에 도입되었으며 이 시스템은 해당 지역주민들이 언제 어디서나 수질을 확인할 수 있도록 되어있다. 그러나 이 시스템, 즉 대형 시스템에 사용되는 이 방법은 매우 높은 비용을 필요로 하고 이로 인해 아파트, 공공시설, 소규모의 지하저수조 및 고가(高架)저수조와 같은 소규모 급수설비에는 적용하기가 곤란하다. 따라서 본 연구에서는 저가의 개별 수질측정 센서모듈에 대한 통합시스템을 제안한다. 개발된 통합 시스템과 인터넷상에서 동작하는 모니터링 프로그램을 이용하여 저수조 시스템 관리자는 음용수에 대한 수질 특성치를 실시간으로 관리할 수 있다. 또한 제안된 시스템이 모듈화 되어있기 때문에 크고 작고의 규모에 관계없이 저비용으로 다양한 저수조나 정수장에 쉽게 설치할 수 있다.

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The Economic Cooperation Potential of East Asia's RCEP Agreement

  • Armstrong, Shiro;Drysdale, Peter
    • East Asian Economic Review
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    • 제26권1호
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    • pp.3-25
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    • 2022
  • East Asia's Regional Comprehensive Economic Partnership (RCEP) came into force in 2022 as the world's largest free trade agreement. RCEP was concluded, signed and brought into force in the face of major international uncertainty and is a significant boost to the global trading system. RCEP brings Australia, China, Japan, South Korea and New Zealand into the same agreement with the ten member ASEAN group at its centre. It keeps markets open and updates trade and investment rules in East Asia, a major centre of global economic activity, at a time of rising protectionism when the WTO itself is under threat. The agreement builds on ASEAN's free trade agreements and strengthens ASEAN centrality. One of the pillars of RCEP is an economic cooperation agenda which has its antecedents in ASEAN's approach to bringing along its least developed members and builds on the experience of capacity building in APEC and technical cooperation under the ASEAN Australia-New Zealand Free Trade Agreement. There is an opportunity to create a framework that facilitates deeper economic cooperation that involves experience-sharing, extending RCEP's rules and membership at the same time as strengthening political cooperation. The paper suggests some areas that might be best suited to cooperation - that is confidence and trust building instead of or before negotiation - and discusses how non-members may be engaged and the membership expanded. Options such as multilateralising provisions and becoming a platform for policy convergence and coordinating unilateral reforms are canvassed.

The Role of Social Work in Mental Health in a Variable Multicultural Environment

  • SEENIVASAN, R.
    • 웰빙융합연구
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    • 제3권2호
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    • pp.21-26
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    • 2020
  • The purpose of this article is to capture this situation within the changes that take place due to it, inside the Greek society where there is a great need for professional social workers who are able to work targeted and effectively with foreigners, both children and adults, who have or develop mental health problems for the very first time. Over the recent decades the increasing number of migration flows has exerted and continues to exert great pressure on the health system and on the welfare structures of Greece. The bases for the development of a rudimentary reception and integration system that still is in progress have been delayed, while there has been no happy medium, between the enormous pressure that foreigner users of this system put on, and the humanitarian obligation of a well-governed state towards all residents of the country. Straight through everyday clinical practice in the field of intercultural work, social work has the knowledge and techniques for a total management of emerging problems and at the same time provides a value system with an ethical background which approaches refugees and migrants in order to provide quality services, mostly to users of mental health services.

Multimedia Presentation Authoring and Virtual Collaboration in Medicine

  • Hong, Chul-Eui
    • Journal of information and communication convergence engineering
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    • 제8권6호
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    • pp.690-696
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    • 2010
  • Web-based virtual collaboration is increasingly gaining popularity in almost every area in our society due to the fact that it can bridge the gap imposed by time and geographical constraints. However, in medical field, such collaboration has been less popular than other fields. Some of the reasons were timeliness, security, and preciseness of the information they are dealing with. In this paper, we are proposing a web-based distributed medical collaboration system called Virtual Collaboration System for Medicine (VCSM) for medical doctors that meet the needs. The proposed system consists of two parts - multimedia presentation and recordable virtual collaboration. The former supports synchronized multimedia presentation using Synchronous Multimedia Integration Language (SMIL.) It allows synchronization of the contents of a PowerPoint presentation file and a video file. The presentation may be provided to the participants before the discussion begins. Next, in the virtual collaboration stage, participants can use text along with associated symbols during the discussion over the presented medical images. The symbols such as arrows or polygons can be set or removed dynamically to represent areas of interest in digital images using so called layered architecture that separates image layer from annotation layer. XML files are used to record participants' opinions along with the symbols over some particular images

Future Challenges and Perspectives of Digital Dance Interventions for Depression in Older Adults

  • Zhiting Zhang;Qingfeng Zhang
    • International Journal of Advanced Culture Technology
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    • 제12권2호
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    • pp.72-89
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    • 2024
  • Depression is a common disorder among the elderly, significantly affecting their quality of life. Traditional dance interventions, although beneficial, have limitations in convenience, personalization, and retention. With the advent of digital technology, digital dance interventions have emerged as a potential solution to these limitations. This paper involves an extensive review of literature on digital dance interventions. Research databases were searched for studies that focus on the use of digital dance in treating depression among older adults. The review also includes analyses of the advancements in digital dance technology, its application in therapeutic settings, and the evaluation of its efficacy. The paper identifies three main challenges in the current digital dance intervention research: real-time dynamic assessment, multimodal dance generation, and improving compliance. Despite these challenges, digital dance interventions show promise in addressing the limitations of traditional dance therapy. The research suggests that the integration of human-computer interaction and personalized approaches in digital dance interventions could significantly improve outcomes in elderly patients with depression. Digital dance interventions represent a novel and promising approach to treating depression in older adults. Future research should focus on overcoming the identified challenges and enhancing the effectiveness of these interventions.

유아문화예술교육의 학습원리와 교육효과를 적용한 교수학습지도방안 연구 (A study on the Convergence Learning Guidance Method for Adolescents with Disabilities Applying the Eurhythmics Rhythm Element)

  • 변기담;남상문
    • 문화기술의 융합
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    • 제10권3호
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    • pp.551-557
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    • 2024
  • 유아문화예술교육은 자신을 표현하면서 사회를 이해하는 과정으로 유아의 삶 전반에 큰 영향을 준다. 유아마다 발달 특성이 다르기에 개별적 다양성을 고려해야 한다는 개별화의 원리와 유아들이 놀이를 통한 즐거움으로 체험활동에 대한 적극적인 태도를 형성하는 놀이 중심의 원리, 전인적인 발달에 밑받침이 되는 통합적 원리, 유아가 직접 만지고 조작해 보는 경험을 제공하는 직접경험의 원리를 활용하였다. 도입에서는 통한 재료의 탐색과 생각나누기, 다함께 책을 읽고 나누기를 진행하고, 전개1과 전개2에서는 문화예술영역인 미술, 음악, 신체표현, 동극, 영화, 사진 등 예술적 표현을 즐기면서 자신의 생각을 창의적으로 표상하도록 하였다. 마무리 단계에서는 유아가 창출해낸 결과물을 함께 감상하고 자신의 생각을 발표하는 과정으로 서로의 의견을 나눌 수 있는 시간으로 구성한 교수학습지도안을 개발하였다. 유아문화예술교육을 통한 교육적 효과는 유아들이 자신의 흥미에 따라 탐구하는 학습이 강조되는 유아기에 개발하는 것이 효과적이므로, 이 연구에서는 유아문화예술교육에 적용할 수 있는 다양한 교육방안과 장르의 융합적 교육이 반영된 학습지도방안을 제시하였다.

Self Charging Sulfanilic Acid Azocromotrop/Reduced Graphene Oxide Decorated Nickel Oxide/Iron Oxide Solar Supercapacitor for Energy Storage Application

  • Saha, Sanjit;Jana, Milan;Samanta, Pranab;Murmu, Naresh Chandra;Lee, Joong Hee;Kuila, Tapas
    • Composites Research
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    • 제29권4호
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    • pp.179-185
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    • 2016
  • A self-charging supercapacitor is constructed through simple integration of the energy storage and photo exited materials at the photo electrode. The large band gap of $NiO/Fe_3O_4$ heterostructure generates photo electron at the photo electrode and store the charges through redox mechanism at the counter electrode. Sulfanilic acid azocromotrop/reduced graphene oxide layer at the photo electrode trapped the photo generated hole and store the charge by forming double layer. The solar supercapacitor device is charged within 400 s up to 0.5 V and exhibited a high specific capacitance of ~908 F/g against 1.5 A/g load. The solar illuminated supercapacitor shows a high energy and power density of 33.4 Wh/kg and 385 W/kg along with a very low relaxation time of ~15 ms ensuring the utility of the self charging device in the various field of energy storage and optoelectronic application.

Finding Optimal Controls for Helicopter Maneuvers Using the Direct Multiple-Shooting Method

  • Kim, Min-Jae;Hong, Ji-Seung;Kim, Chang-Joo
    • International Journal of Aeronautical and Space Sciences
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    • 제11권1호
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    • pp.10-18
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    • 2010
  • The purpose of this paper deals with direct multiple-shooting method (DMS) to resolve helicopter maneuver problems of helicopters. The maneuver problem is transformed into nonlinear problems and solved DMS technique. The DMS method is easy in handling constraints and it has large convergence radius compared to other strategies. When parameterized with piecewise constant controls, the problems become most effectively tractable because the search direction is easily estimated by solving the structured Karush-Kuhn-Tucker (KKT) system. However, generally the computation of function, gradients and Hessian matrices has considerably time-consuming for complex system such as helicopter. This study focused on the approximation of the KKT system using the matrix exponential and its integrals. The propose method is validated by solving optimal control problems for the linear system where the KKT system is exactly expressed with the matrix exponential and its integrals. The trajectory tracking problem of various maneuvers like bob up, sidestep near hovering flight speed and hurdle hop, slalom, transient turn, acceleration and deceleration are analyzed to investigate the effects of algorithmic details. The results show the matrix exponential approach to compute gradients and the Hessian matrix is most efficient among the implemented methods when combined with the mixed time integration method for the system dynamics. The analyses with the proposed method show good convergence and capability of tracking the prescribed trajectory. Therefore, it can be used to solve critical areas of helicopter flight dynamic problems.

Application of Urban Computing to Explore Living Environment Characteristics in Seoul : Integration of S-Dot Sensor and Urban Data

  • Daehwan Kim;Woomin Nam;Keon Chul Park
    • 인터넷정보학회논문지
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    • 제24권4호
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    • pp.65-76
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    • 2023
  • This paper identifies the aspects of living environment elements (PM2.5, PM10, Noise) throughout Seoul and the urban characteristics that affect them by utilizing the big data of the S-Dot sensors in Seoul, which has recently become a hot topic. In other words, it proposes a big data based urban computing research methodology and research direction to confirm the relationship between urban characteristics and living environments that directly affect citizens. The temporal range is from 2020 to 2021, which is the available range of time series data for S-Dot sensors, and the spatial range is throughout Seoul by 500mX500m GRID. First of all, as part of analyzing specific living environment patterns, simple trends through EDA are identified, and cluster analysis is conducted based on the trends. After that, in order to derive specific urban planning factors of each cluster, basic statistical analysis such as ANOVA, OLS and MNL analysis were conducted to confirm more specific characteristics. As a result of this study, cluster patterns of environment elements(PM2.5, PM10, Noise) and urban factors that affect them are identified, and there are areas with relatively high or low long-term living environment values compared to other regions. The results of this study are believed to be a reference for urban planning management measures for vulnerable areas of living environment, and it is expected to be an exploratory study that can provide directions to urban computing field, especially related to environmental data in the future.