• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2885-2889
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• 2007

In this study, the effect of particle aggregation on dynamic response time of Electrorheological (ER) fluid is investigated. The particle aggregation time is defined as the time interval between the application of the field and the formation of the first chain bridging the two electrodes. The dynamic response times of an ER fluid sheared between two concentric cylinders have been obtained under two different experimental conditions: the one is that the electric field is induced before shearing, and the other is that the electric field is induced after shearing. From the difference between two response times, the particle aggregation times are determined under various electric fields and shear rates. The experimental results show that the aggregation rate is decreased with an increase of shear rate, while electric field has little effect on it. Therefore, it is verified that the hydrodynamic force hinders the formation of chain-like structures.

• Journal of the Korean Statistical Society
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• 제9권1호
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• pp.39-60
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• 1980

In the last paper, we have discussed the cannonical representatin of a dynamic linear model, on which some aggregation schemes were devised. The relationships of those aggregation schemes with dynamic properties were investigated. This paper tries to analyse she control strategy for the aggregated linear dynamic model and to investigate the dynamic properties of disaggregative model controlled by aggregated model. For the logical consistency with the last paper, all the sections and all the equations are numbered in a sequence.

• Journal of Information Processing Systems
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• 제19권1호
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• pp.80-88
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• 2023

RGB-thermal (RGB-T) tracking using unmanned aerial vehicles (UAVs) involves challenges with regards to the similarity of objects, occlusion, fast motion, and motion blur, among other issues. In this study, we propose dynamic tracking aggregation (DTA) as a unified framework to perform object detection and data association. The proposed approach obtains fused features based a transformer model and an L1-norm strategy. To link the current frame with recent information, a dynamically updated embedding called dynamic tracking identification (DTID) is used to model the iterative tracking process. For object association, we designed a long short-term tracking aggregation module for dynamic feature propagation to match spatial and temporal embeddings. DTA achieved a highly competitive performance in an experimental evaluation on public benchmark datasets.

• 대한전기학회논문지:전력기술부문A
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• 제50권1호
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• pp.6-12
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• 2001

This paper deals with the development of dynamic equivalents of the Korea Electric Corporation (KEPCO) systems. The weak coupling method is chosen for the most suitable coherency identification to represent the characteristics of the KEPCO system by the dynamic characteristic comparison of several coherency identification methods. Also, this paper shows the detail aggregation of generator groups makes a better representation of the dynamic and static characteristics of the original system than the classical aggregation. The simulation results of the developed KEPCO equivalent system are presented in comparison with the original system to illustrate the validity of the equivalent system are presented in comparison with the original system to illustrate the validity of the equivalent system.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.605-611
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• 2001

A numerical technique for simulating the aggregation of charged particles was presented with a Brownian dynamic simulation in the free molecular regime. The Langevin equation was used for tracking each particle making up an aggregate. A periodic boundary condition was used for calculation of the aggregation process in each cell with 500 primary particles of 16 nm in diameter. We considered the thermal force and the electrostatic force for the calculation of the particle motion. The morphological shape of aggregates was described in terms of the fractal dimension. The fractal dimension for the uncharged aggregate was $D_{f}=1.761$. The fractal dimension changed slightly for the various amounts of bipolar charge. However, in case of unipolar charge, the fractal dimension decreased from 1.641 to 1.537 with the increase of the average number of charges on the particles from 0.2 to 0.3 in initial states.

• Structural Engineering and Mechanics
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• 제57권3호
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• pp.441-456
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• 2016

This work reports wave propagation in the nanocomposite cylinders that reinforced by straight single-walled carbon nanotubes based on a mesh-free method. Moving least square shape functions have been used for approximation of displacement field in weak form of motion equation. The straight carbon nanotubes (CNTs) are assumed to be oriented in specific or random directions or locally aggregated into some clusters. In this simulation, an axisymmetric model is used and also the volume fractions of the CNTs and clusters are assumed to be functionally graded along the thickness. So, material properties of the carbon nanotube reinforced composite cylinders are variable and estimated based on the Eshelby-Mori-Tanaka approach. The effects of orientation, aggregation and volume fractions of the functionally graded clusters and CNTs on dynamic behavior of nanocomposite cylinders are studied. This study results show that orientation and aggregation of CNTs have significant effects on the effective stiffness and dynamic behaviors.

• 정보처리학회논문지B
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• 제16B권4호
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• pp.327-331
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• 2009

퍼지 논리에서 불확실성의 병합은 일반적으로 t-norm 과 t-conorm 같은 연산자에 의해 수행된다. 그러나 기존의 병합 연산자는 다음과 같은 단점을 가지고 있다 : 첫째, 그들은 상황에 독립적이다. 결과적으로 동적 병합 과정에 적절히 적용하기 어렵다. 둘째, 의사결정 과정에의 직관적 연결성을 제공하지 못한다. 이러한 문제점을 해결하기 위해 의사결정 과정에서 옵션들의 강점 정도를 반영해 주는 퍼지 다차원 의사결정분석에 기반을 둔 $\varepsilon$-AMDA 알고리즘을 제안한다. $\varepsilon$-AMDA 알고리즘은 옵션의 강점 정도를 나타내 주는 매개변수의 값에 따라 최소값(옵션의 최약점)과 최대값(옵션의 최강점) 사이에서 적응적인 병합 결과를 생성한다. 이러한 관점에서 이는 동적 병합에 적용될 수 있다. 또한, 의사결정을 위한 퍼지 다차원 의사결정 분석에 대한 메커니즘을 제공하고 의사결정 과정에의 직관적 연결성을 제공한다. 결과적으로 제안된 방법은 의사결정자가 옵션의 강점 정도에 따라 적절한 의사결정을 하도록 지원할 수 있다.

• Journal of information and communication convergence engineering
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• 제3권1호
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• pp.13-17
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• 2005

The link e daggregation between 10GbE switches requires an advanced framistribution method to be properly and efficiently applied. The fixed or dynamic frame distribution methods, formerly proposed, cannot fully utilize the aggregated links, where the receiving terminal only attaches to a pre-specified link among multiple physical links. A frame distribution method using padding is proposed for the link aggregation between 10GbE switches to solve this problem. We compared the performance of the proposed method with those of the static and dynamic frame distribution methods. As a result, the proposed method shows a better performance when the offered load is below 0.7 and the average length of the frames is longer than 954 bytes.

• 한국자기공명학회논문지
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• 제26권1호
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• pp.17-20
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• 2022

High-pressure (HP) NMR is a versatile tool to investigate diverse features of proteins. This technique has been particularly powerful to elucidate structural dynamics that only populates sufficiently in a pressurized condition. Amyloidogenic proteins, which are prone to aggregate and form amyloid fibrils, often maintains highly dynamic states in its native or aggregation-prone states, and HP NMR contributed much to advance our understandings of the dynamic behaviors of amyloidogenic proteins and the molecular mechanisms of their aggregation. In this mini review, we therefore summarize recent HP NMR studies on amyloid-beta (Aβ), the representative amyloidogenic intrinsically disordered protein (IDP).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.342-344
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• 2006

The modem enormous electric power system has made power system analysis much more complex and difficult. For effective analysis of the power system, model reduction and aggregation is required. In this paper, a new aggregation method is presented to aggregate the coherent generators in the large scale power system while matching the power flow. In order to demonstrate the effects of this aggregation method, it is applied to a small scale power system. A multi-variable control technique of $H_{\infty}$ control is also applied to enhance the dynamic stability of the aggregated power system.