• Title/Summary/Keyword: 시간그래프

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CIGS박막 태양전지소자의 온도변화에 따른 전기적 특성 분석

  • Kim, Sun-Gon;Kim, Sang-Seop;Choe, Byeong-Deok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.224.2-224.2
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    • 2013
  • 본 연구에서는 CIGS박막 태양전지의 온도 및 시간 인가에 따른 전기적 특성 변화를 분석하였다. 실험에서는 온도 스트레스를 $25^{\circ}C$, $50^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$에서 각각 10시간씩 인가한 후에 Dark I-V와 C-V측정을 통해 전기적 특성 변화를 분석하였다. $25^{\circ}C$일 때를 초기 온도로 하여 특성을 측정한 것과 온도별로 노출시킨 후에 측정한 것을 비교했을 때 소자의 효율은 $100^{\circ}C$에서 감소하기 시작하였고, 인가한 온도가 높을수록 점점 많이 감소하는 모습이 나타났다. 이와 비슷하게 I-V그래프와 C-V그래프의 모습도 초기 값과 비교해서 변화하는 모습이 나타났고, 온도가 높아질수록 점점 변화하는 양이 증가하였다. I-V그래프에서 Diode ideality factor는 온도변화에 따라 초기 값 대비 증가하는 모습이 나타났다. 온도에 노출되기 전보다 노출된 후에 current와 capacitance가 감소하는 경향을 보이는데, 이는 온도의 영향으로 인해 소자의 결함이 증가하여 전하들의 반응에 영향을 주었기 때문으로 판단된다.

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Development of CPLD technology mapping algorithm improving run-time under Time Constraint (시간적 조건에서 실행시간을 개선한 CPLD 기술 매핑 알고리즘 개발)

  • 윤충모;김희석
    • Journal of the Korea Society of Computer and Information
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    • v.4 no.3
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    • pp.35-46
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    • 1999
  • In this paper, we propose a new CPLD technology mapping algorithm improving run-time under time constraint. In our technology mapping algorithm. a given logic equation is constructed as the DAG type. then the DAG is reconstructed by replicating the node that outdegree is more than or equal to 2. As a result, it makes delay time and the number of CLBs, run-time to be minimized. Also. after the number of multi-level is defined and cost of each nodes is calculated, the graph is partitioned in order to fit to k that is the number of OR term within Cl.B. The partitioned nodes are merged through collapsing and bin packing is performed in order to fit to the number of OR term within CLB. In the results of experiments to MCNC circuits for logic synthesis benchmark, we can shows that proposed technology mapping algorithm reduces run-time much more than the TMCPLD.

A Synthetic Dataset for Korean Knowledge Graph-to-Text Generation (한국어 지식 그래프-투-텍스트 생성을 위한 데이터셋 자동 구축)

  • Dahyun Jung;Seungyoon Lee;SeungJun Lee;Jaehyung Seo;Sugyeong Eo;Chanjun Park;Yuna Hur;Heuiseok Lim
    • Annual Conference on Human and Language Technology
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    • 2022.10a
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    • pp.219-224
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    • 2022
  • 최근 딥러닝이 상식 정보를 추론하지 못하거나, 해석 불가능하다는 한계점을 보완하기 위해 지식 그래프를 기반으로 자연어 텍스트를 생성하는 연구가 중요하게 수행되고 있다. 그러나 이를 위해서 대량의 지식 그래프와 이에 대응되는 문장쌍이 요구되는데, 이를 구축하는 데는 시간과 비용이 많이 소요되는 한계점이 존재한다. 또한 하나의 그래프에 다수의 문장을 생성할 수 있기에 구축자 별로 품질 차이가 발생하게 되고, 데이터 균등성에 문제가 발생하게 된다. 이에 본 논문은 공개된 지식 그래프인 디비피디아를 활용하여 전문가의 도움 없이 자동으로 데이터를 쉽고 빠르게 구축하는 방법론을 제안한다. 이를 기반으로 KoBART와 mBART, mT5와 같은 한국어를 포함한 대용량 언어모델을 활용하여 문장 생성 실험을 진행하였다. 실험 결과 mBART를 활용하여 미세 조정 학습을 진행한 모델이 좋은 성능을 보였고, 자연스러운 문장을 생성하는데 효과적임을 확인하였다.

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A Study on the Efficient Task Scheduling by the Reconstructed Task Graph (태스크 그래프의 재구성에 의한 효율적 태스크 스케줄링에 관한 연구)

  • Byun, Seung-Hwan;Yoo, Kwan-Jong
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.9
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    • pp.2235-2246
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    • 1997
  • This paper presents an effective heuristic task scheduling algorithm for multiprocessor systems. To execute task scheduling effectively which is defined as an allocation of m's tasks onto n's processors(m > n), several problems almost at NP-hard should be cleaned up. The purpose of the task scheduling obtains the minimum execution time by mapping the tasks on a system topology or reduces the total execution time to give a minimum system topology. In order to solve this problem, in this paper, the task scheduling is done by redefining a task graph to a reconstructed task graph (RTG). An RTG is obtained by merging or copying nodes to equal the number of nodes on each level of the task graph to the number of processors of the system topology and then directly scheduled to the system topology. This method obtains a fast scheduling time and a simple scheduling method, and near-optimal execution time without executing steps such as the refinement step and the duplication step after the task scheduling.

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Rheological Properties of Bread Dough Added with Flour Ferments by Seed Mash and Lactic Acid Bacteria (Seed Mash와 유산균 발효액을 첨가한 밀가루 반죽의 물성학적 특성)

  • Lee, Myung-Ku;Lee, Jeong-Hoon;Lee, Si-Kyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.3
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    • pp.346-351
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    • 2009
  • This study was carried out to determine the rheological properties of bread doughs containing flour-ferments prepared with seed mash obtained by Koji incubation, yeast, and lactic acid bacteria, using farinograph, extensograph, amylograph, and large scale-dough mixer. According to farinograph, the addition of the flour-ferments did not influence the water-absorption rate of doughs, regardless of the kinds of flour-ferments, however, it increased development time and decreased stability of doughs. According to extensograph, both dough resistance and resistance-to-extensibility ratio increased with the addition of flour-ferments. Especially the dough containing the flour-ferments prepared with seed mash, S. cerervisiae, and L. brevis showed the highest resistance-to-extensibility ratio. According to amylograph, although the doughs containing the flour-ferments did not show the differences in gelatinization temperature and temperature at maximum viscosity with the control which does not contain the flour-ferments, they showed lower maximum viscosity than the control. They also showed lower development value and faster development time.

Algorithm for Maximum Cycle Detection of Directed and Undirected General Graphs (방향과 무 방향 일반 그래프의 최대 사이클 검출 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.6
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    • pp.91-97
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    • 2022
  • There is hare and tortoise racing algorithm(HTA) for single-source(SS) singly linked list(SLL) with O(n) time complexity. But the fast method is unknown for general graph with multi-source, multi-destination, and multi-branch(MSMDMB). This paper suggests linear time cycle detection algorithm for given undirected and digraph with MSMDMB. The proposed method reduced the given graph G contained with unnecessary vertices(or nodes) to cycle into reduced graph G' with only necessary vertices(or nodes) to cycle based on the condition of cycle formation. For the reduced graph G', we can be find the cycle set C and cycle length λ using linear search within linear time. As a result of experiment data, the proposed algorithm can be obtained the cycle for whole data.

Fast algorithm for incorporating start and goal points into the map represented in a generalized visibility graph (출발점과 목표점을 일반화 가시성그래프로 표현된 맵에 포함하기 위한 빠른 알고리즘)

  • Yu, Kyeon-Ah;Jeon, Hyun-Joo
    • Journal of the Korea Society for Simulation
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    • v.15 no.2
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    • pp.31-39
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    • 2006
  • The visibility graph is a well-known method for efficient path-finding with the minimum search space modelling the game world. The generalized visibility graph is constructed on the expanded obstacle boundaries to eliminate the "wall-hugging" problem which is a major disadvantage of using the visibility graph. The paths generated by the generalized visibility graph are guaranteed to be near optimal and natural-looking. In this paper we propose the method to apply the generalized visibility graph efficiently for game characters who moves among static obstacles between varying start and goal points. Even though the space is minimal once the generalized visibility graph is constructed, the construction itself is time-consuming in checking the intersection between every two links connecting nodes. The idea is that we build the map for static obstacles first and then incorporate start and goal nodes quickly. The incorporation of start and goal nodes is the part that must be executed repeatedly. Therefore we propose to use the rotational plane-sweep algorithm in the computational geometry for incorporating start and goal nodes efficiently. The simulation result shows that the execution time has been improved by 39%-68% according to running times in the game environment with multiple static obstacles.

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A Query Model for Consecutive Analyses of Dynamic Multivariate Graphs (동적 다변량 그래프의 연속적 분석을 위한 질의 모델 설계 및 구현)

  • Bae, Yechan;Ham, Doyoung;Kim, Taeyang;Jeong, Hayjin;Kim, Dongyoon
    • The Journal of Korean Association of Computer Education
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    • v.17 no.6
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    • pp.103-113
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    • 2014
  • This study designed and implemented a query model for consecutive analyses of dynamic multivariate graph data. First, the query model consists of two procedures; setting the discriminant function, and determining an alteration method. Second, the query model was implemented as a query system that consists of a query panel, a graph visualization panel, and a property panel. A Node-Link Diagram and the Force-Directed Graph Drawing algorithm were used for the visualization of the graph. The results of the queries are visually presented through the graph visualization panel. Finally, this study used the data of worldwide import & export data of small arms to verify our model. The significance of this research is in the fact that, through the model which is able to conduct consecutive analyses on dynamic graph data, it helps overcome the limitations of previous models which can only perform discrete analysis on dynamic data. This research is expected to contribute to future studies such as online decision making and complex network analysis, that use dynamic graph models.

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Development of Visualization Tool for Information Diffusion Network (점진적으로 확산하는 정보 네트워크의 시각화 도구 개발)

  • Yu, Jiyeon;Bae, Joonhyun;Kim, Sangwook
    • Proceedings of the Korea Information Processing Society Conference
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    • 2009.04a
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    • pp.581-584
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    • 2009
  • 본 논문에서는 시간의 축에 따라 점진적으로 확산되는 정보 네트워크를 효과적으로 표현할 수 있는 시각화 도구를 소개하고자 한다. 이것은 기존의 정적인 데이터에 대한 정적인 시각화 결과물을 제시하는 시각화 도구들과는 달리, 시간의 축에 따라 동적으로 성장하는 데이터를 효과적으로 표현할 수 있다는데 그 차이가 있다. 이를 위해 그래프 기반의 정보 확산 네트워크 모델을 정의 하고, 이 그래프에 시간의 축에 따른 데이터의 성장을 반영하여, 정보 확산 과정을 시각화 할 수 있는 도구를 제작하였다. 결론적으로, 본 논문에서 제시하는 도구는 시간의 축에 따라 점진적으로 성장하는 정보 네트워크의 성장 과정을 시각화함으로 해서, 복잡하게 엉켜 있는 정보들이 어떻게 확산되며, 어떤 모양으로 생겼는지, 또 어떻게 진화하는가에 대한 시각적 재현을 통해 정보 확산 네트워크의 속성을 이해하는데 도움을 줄 수 있는 새로운 시각화 도구를 제시했다는데 그 의미가 있다.

A Study on Optimal Scheduling with Directed Acyclic Graphs Task onto Multiprocessors (다중프로세서에서 비순환 타스크 그래프의 최적 스케쥴링에 관한 연구)

  • 조민환
    • Journal of the Korea Society of Computer and Information
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    • v.4 no.4
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    • pp.40-46
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    • 1999
  • The task scheduling has an effect on system execution time in a precedence constrained task graph onto the multiprocessor system. This problem is known to be NP-hard. many people made an effort to obtain near optimal schedule. We compared modified critical path schedule with many other methods(CP, MH, DL Swapping) For testing this subject, we created randomly a directed acyclic task graph with many root nodes and terminal nodes simulation result convinced for us that the modified critical path algorithm is superior to the other scheduling algorithm.

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