• 제목/요약/키워드: Challenge of Application

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메소-스케일 연소 현상의 공학적 의미와 이해 (Understanding and Engineering Meaning of Meso-Scale Combustion Phenomena)

  • 김남일
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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    • pp.287-289
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    • 2015
  • Meso-scale combustion is defined as combustion phenomena within limited characteristic length scales that are comparable with the laminar flame length scales. In the laminar flame theory, four representative length scales have been involved; i.e., a reaction layer thickness, a thermal layer thickness, a quenching distance, and a Markstein length. When the effects of these length scales on the flame characteristics are understood, the laminar flame theories can be clarified. Therefore, a study on the meso-scale combustion phenomena should not be thought as just a specific phenomena occurring in an exceptional combustion condition. Instead, all combustion phenomena within meso-scale spaces need to be explained by our knowledge. During this challenge, our understanding on laminar flame structures can be extended. Considering that most turbulent combustion phenomena in engineering application are still have local laminar flame structures, studies on laminar flame structures need to be re-visited especially in academic aspects.

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나노미터 표면가공시 절삭조건에 관한 연구 (A Study on the Cutting Conditions in Machining for Nanometer Surface)

  • 문재일;김부태;김영일;허성중
    • 한국정밀공학회지
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    • 제15권9호
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    • pp.152-157
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    • 1998
  • Since early 1960s, the high precision machining technology, so called ultra-precision technology or nano technology, has been developed in many Held based on single point diamond turning technology. The major application of this technology is the optical components with aspherical surfaces. Now a days, customer requires the smaller and lighter optical elements, such as camera video and etc., with higher performance for convenience. So, the manufacturer focuses on the ultra-precision technology. Thus, this technology becomes the major target to challenge the advanced barrier for the next machining technology.

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중학교 체육과 STEAM 융합을 통한 창의·융합 수업 모듈 요소 도출 및 수업 모듈 제시 (Drawing up class module elements of originality and convergence and suggesting class modules by combining middle school physical education and STEAM)

  • 홍희정;임현주
    • 한국웰니스학회지
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    • 제14권2호
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    • pp.207-223
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    • 2019
  • 본 연구의 목적은 체육과 신체활동 영역별(건강, 도전, 경쟁, 표현) 내용요소와 STEAM과의 융합을 통해 창의·융합 수업모듈 요소를 도출하는 것이며, 아울러 창의·융합 수업 모듈을 제시하는 것에 있다. 이를 위해 문헌연구, 포커스 그룹 인터뷰(FGI), 전문가 협의 방법을 실시하였으며 이를 통하여 다음과 같은 연구 결과를 도출하였다. 먼저 창의·융합 수업 모듈 요소와 관련하여 첫째, 건강 영역의 창의·융합 수업 모듈 요소는 자세 분석을 통한 위험성 도출, 신체활동량 분석과 설계 등 총 11개로 제시되었다. 둘째, 도전 영역의 모듈 요소는 총 6개로 목표 달성 저해 요인 예상, 효율적 운동을 위한 모델링 등의 내용이 도출되었으며, 경쟁 영역의 융합 요소는 17개로 경기 기록 분석, 경기데이터 저장을 위한 어플 제작 등의 내용이 제시되었다. 마지막으로 표현 영역의 창의·융합 모듈 요소는 총 10개로 움직임 표현 기술 향상을 위한 모델링, 움직임 표현 기록을 위한 기호화 등의 내용이 도출되었다. 아울러 수업 모듈은 건강 영역에서는 공학(E: Engineering) 분야와의 융합과 관련된 내용이 제시되었으며, 도전 영역에서는 기술(T: Technology)과의 융합, 경쟁 영역에서는 예술(A: Art)와의 융합, 표현 영역에서는 예술(A: Art)와, 수학(M: Mathematics)기호와)과의 융합을 통한 내용이 제시되었다.

KHistory: 한국사 객관식 문제 자동 생성 시스템 (KHistory: A System for Automatic Generation of Multiple Choice Questions on the History of Korea)

  • 김성원;정해성;진재환;이명준
    • 예술인문사회 융합 멀티미디어 논문지
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    • 제7권1호
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    • pp.253-263
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    • 2017
  • 최근 한국사에 필요성이 증대하고 사람들의 관심이 높아지면서, 한국사 학습을 위한 다양한 어플리케이션들이 등장하고 있다. 이러한 기존의 한국사 학습 어플리케이션은 문제은행 방식으로 사용자들에게 객관식 문제를 제공한다. 하지만 문제은행 방식은 미리 저장된 문제를 가져와 사용함으로써 계속 사용할 경우 중복되는 문제로 인하여 필연적으로 학습효율이 떨어지게 된다. 본 논문에서는 한국사 데이터베이스를 기반으로 한국사 학습문제를 자동적으로 생성하는 시스템인 K-History의 개발과 이를 활용한 한국사 학습 어플리케이션인 한국사 무한도전의 개발에 대하여 기술한다. K-History의 개발을 위하여 한국사 학습 교재를 바탕으로 다양한 한국사 학습 문제를 분석하여 학습문제의 대표 유형을 분류하고, 발견된 유형에 따라 문제를 생성하는 알고리즘을 제안한다. 개발된 한국사 학습문제 생성 기법은 다양한 학습 시스템에 적용되어 문제 생성을 위한 비용을 줄일 수 있으며, 다양하게 생성된 학습문제를 통하여 학습자의 학습효율을 높일 수 있을 것으로 기대된다.

AMG-CG method for numerical analysis of high-rise structures on heterogeneous platforms with GPUs

  • Li, Zuohua;Shan, Qingfei;Ning, Jiafei;Li, Yu;Guo, Kaisheng;Teng, Jun
    • Computers and Concrete
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    • 제29권2호
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    • pp.93-105
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    • 2022
  • The degrees of freedom (DOFs) of high-rise structures increase rapidly due to the need for refined analysis, which poses a challenge toward a computationally efficient method for numerical analysis of high-rise structures using the finite element method (FEM). This paper presented an efficient iterative method, an algebraic multigrid (AMG) with a Jacobi overrelaxation smoother preconditioned conjugate gradient method (AMG-CG) used for solving large-scale structural system equations running on heterogeneous platforms with parallel accelerator graphics processing units (GPUs) enabled. Furthermore, an AMG-CG FEM application framework was established for the numerical analysis of high-rise structures. In the proposed method, the coarsening method, the optimal relaxation coefficient of the JOR smoother, the smoothing times, and the solution method for the coarsest grid of an AMG preconditioner were investigated via several numerical benchmarks of high-rise structures. The accuracy and the efficiency of the proposed FEM application framework were compared using the mature software Abaqus, and there were speedups of up to 18.4x when using an NVIDIA K40C GPU hosted in a workstation. The results demonstrated that the proposed method could improve the computational efficiency of solving structural system equations, and the AMG-CG FEM application framework was inherently suitable for numerical analysis of high-rise structures.

몬테카를로 시뮬레이션을 이용한 하안단구 10Be 수직단면 연대측정 (Cosmogenic 10Be Depth Profile Dating of Strath Terrace Abandonment using Monte Carlo Simulation)

  • 김동은;성영배;김종근
    • 한국지형학회지
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    • 제26권4호
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    • pp.21-31
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    • 2019
  • Timing of terrace formation is a key information for understanding the evolution of fluvial systems. In particular, dating strath terrace (i.e. timing of terrace abandonment) is more difficult than depositional terrace that is conventionally constrained by radiocarbon, OSL and other dating methods targeting samples within terrace deposit. Surface exposure dating utilizing cosmogenic 10Be provides more reliability because it can be applied directly to the surface of a fluvial terrace. Thus, this method has been increasingly used for alluvial deposits. As well as other geomorphic surfaces over the last decades. Some inherent conditions, however, such as post-depositional 10Be concentration (i.e. inheritance), surface erosion rate, and density change challenge the application of cosmogenic 10Be to depositional terrace surface against simple bedrock surface. Here we present the first application of 10Be depth profile dating to a thin-gravel covered strath terrace in Korea. Monte Carlo simulation (MCS) helped us in better constraining the timing of abandonment of the strath terrace, since which its surface stochastically denuded with time, causing unexpected change of 10Be production with depth. The age of the strath terrace estimated by MCS was 109 ka, ~4% older than the one (104 ka) calculated by simple depth profile dating, which yielded the best-fit surface erosion rate of 2.1 mm/ka. Our study demonstrates that the application of 10Be depth profile dating of strath terrace using MCS is more robust and reliable because it considers post-depositional change of initial conditions such as erosion rate.

플러그 앤드 플래이(Plug-and-Play)개념을 이용한 이형 응용 프로그램의 통합 기법 (The Integration of heterogeneous applications through Plug-and Play)

  • 백순철;최중민;장명욱;박상규;민병익;임영환
    • 한국정보처리학회논문지
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    • 제2권6호
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    • pp.947-959
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    • 1995
  • 본 논문에서는 한 응용프로그램의 간단한 접속 및 수행을 통하여, 그 프로그램이 다른 프로그램과 서비스와 정보를 공유할 수 있도록 하는 다중 에이전트 시스템의 개발에 관하여 다룬다. 이를 위하여 3가지 요소를 만들어 사용 하였다. 첫번째 요소인 메타 정보는 새로 접속되는 응용 프로그램을 알아보고 이용하기 위해 필요한 정보를 자동으로 구성한 것이다. 이 메타정보는 모양이 다른 응용 프로그램들을 직접 다룰 때 발생하는 복잡성을 줄여준다. 두번째 요소인 에이전트 모듈은 한 응용 프로그램이 다른 응용 프로그램들과 동일한 행동 양식으로 교류하기 위한 제어를 제공한다. 마지 막으로 세번째 요소인 에이전트간 교류 메시지는 모양이 다른 응용 프로그램일 지라도 서로 교류할 수 있도록, 교류 메시지에 대한 공통의 표현 양식을 제공한다. 이러한 세가지 요소를 사용하여, 임의의 응용 프로그램의 간단한 접속 및 수행을 통한 새로운 시스템의 확장 요구를 만족시킨다.

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식육의 연화증진에 관한 최근의 연구동향 - 적색육의 연도 증진에 이용되는 전기자극의 작용 -

  • 황인호
    • 한국축산식품학회:학술대회논문집
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    • 한국축산식품학회 2002년도 정기총회 및 제29차 춘계국제 학술발표대회
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    • pp.17-25
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    • 2002
  • Application of electrical stimulation in the red meat species (eg. beef and sheep) processing has been erratic around the world and this may reflect an incomplete knowledge of how to optimise the technology. Although it is well established that stimulation increases the rate of post-mortem glycolysis other biochemical and biophysical effects have been implicated with the use of this technology. On the basis of currently available knowledge, this mini-review seeks to examine the current theories about the effect of stimulation on post-mortem muscle. The classical view that stimulation prevents muscle from shortening excessively during rigor development has been expanded to include the possibility that it also results in physical disruption of muscle structure. The interaction of these effects with the acceleration of the rate of proteolysis through activation of the calpain protease system has not been comprehensively reviewed in the past. As a result of conclusion driven, this article highlights several areas that may prove fruitful for further research. The challenge for further development of electrical stimulation systems is optimisation of the activation of the enzyme systems in parallel with manipulation of chilling regimes so as to ensure rigor mortis is achieved at temperatures which minimise shortening. The potential of regional stimulation of sections of the carcass to achieve this outcome is worthy of study given the different fibre composition of muscles and temperature gradients.

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Dynamic knowledge mapping guided by data mining: Application on Healthcare

  • Brahami, Menaouer;Atmani, Baghdad;Matta, Nada
    • Journal of Information Processing Systems
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    • 제9권1호
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    • pp.1-30
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    • 2013
  • The capitalization of know-how, knowledge management, and the control of the constantly growing information mass has become the new strategic challenge for organizations that aim to capture the entire wealth of knowledge (tacit and explicit). Thus, knowledge mapping is a means of (cognitive) navigation to access the resources of the strategic heritage knowledge of an organization. In this paper, we present a new mapping approach based on the Boolean modeling of critical domain knowledge and on the use of different data sources via the data mining technique in order to improve the process of acquiring knowledge explicitly. To evaluate our approach, we have initiated a process of mapping that is guided by machine learning that is artificially operated in the following two stages: data mining and automatic mapping. Data mining is be initially run from an induction of Boolean case studies (explicit). The mapping rules are then used to automatically improve the Boolean model of the mapping of critical knowledge.

A 60GHz Wireless Cooperative Communication System Based on Switching Beamforming

  • Shi, Wei;Wang, Jingjing;Liu, Yun;Niu, Qiuna;Zhang, Hao;Wu, Chunlei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권4호
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    • pp.1590-1610
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    • 2016
  • The challenge of penetrating obstacles along with impact from weak multipath effects makes 60GHz signal very difficult to be transmitted in non-line of sight (NLOS) channel. So 60GHz system is vulnerable to obstructions and thus likely results in link interruption. While the application of cooperative technology to solve link blockage problemin 60GHz system should consider the characteristic of directional transmission for 60GHz signal. Therefore in this paper a system is proposed to solve the link blockage problem in 60GHz NLOS communication environment based on the concept of cooperation and also the beamforming technology, which is the basis of directional transmission for 60GHz communication system. The process of anti-blockage solution with cooperative communication is presented in detail, and the fast switching and recovery schemes are well designed. The theoretical values of symbol error rate (SER) using decode and forward (DF) cooperation and amplify and forward (AF) cooperation are presented respectively when the common channel interference exists. Simulation results demonstrate that the performance based on DF cooperation is better than the performance based on AF cooperation when directional transmission is used.