• Journal of Electrochemical Science and Technology
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• v.5 no.2
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• pp.53-57
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• 2014

With the use of diffusion-limited aggregation modeling, we have investigated the effect of particle drift for dendritic growth. It is found that the morphology of dendritic growth is sensitive to the particle drift, i.e., the larger drift effect results in the denser growth of dendrite. From the analysis using the correlation function, we found the fractional dimension of each dendrite increases as the particles drift increases. Furthermore, we showed the height of dendrite significantly decrease for the slight change of particles drift. Finally, we discussed the strategy to reduce dendritic growth by modifying the transport properties of electrolytes.

• Journal of Electrochemical Science and Technology
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• v.14 no.2
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• pp.194-204
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• 2023

Models based on diffusion-limited aggregation (DLA) have been extensively used to explore the mechanisms of dendritic particle aggregation phenomena. The physical and chemical properties of systems in which DLA aggregates emerge are given in their fractal. In this paper, we present a comprehensive study of the growth of electrodeposited copper dendrites in flat plate electrochemical cells from a fractal perspective. The effects of growth time, applied voltage, copper ion concentration, and electrolyte acidity on the morphology and fractal dimension of deposited copper were examined. 'Phase diagram' set out the variety of electrodeposited copper fractal morphology analysed by metallographic microscopy. The box counting method confirms that the electrodeposited dendritic structures manifestly exhibit fractal character. It was found that with the increase of the voltage and copper ion concentration. The fractal copper size becomes larger and its morphology shifts towards a dendritic structure, with the fractal dimension fluctuating around 1.60-1.70. In addition, the morphology of the deposited copper is significantly affected by the acidity of the electrolyte. The increase in acidity from 0.01 to 1.00 mol/L intensifies the hydrogen precipitation side reactions and the overflow path of hydrogen bubbles affects the fractal growth of copper dendrites.

• Journal of Korea Spatial Information System Society
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• v.12 no.1
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• pp.10-17
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• 2010

Sensor nodes used in Geosensor network are resource limited and power constrained. So it is necessary to research on routing protocols to gather data by using energy efficiently. Wireless sensor networks collect data gathered from sensor nodes by transfering it to the sink using multihop. However, it has two problems. First, the existing works require unnecessary data transmission for choosing a proper parent node to transfer data. Secondly, they have a large number of data transmission because each sensor node has a different path. To solves the problems, we, in this paper, propose a designated path based data aggregation scheme for efficient energy management in WSNs. The proposed scheme can reduce unnecessary data transmission by pre-determining a set of paths and can enable all the sensor nodes to participate in gathering data by running them in round-robin fashion. We show from performance analysis that the proposed scheme is more energy efficient than the existing directed diffusion(DD) and the hierarchical data aggregation(HDA).

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.7
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• pp.858-863
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• 2005

Sensor network is subject to novel problems and constraints because it is composed of thousands of tiny devices with very limited resources. The large number of motes in a sensor network means that there will be some failing nodes owing to the lack of battery in sensor nodes. Therefore, it is imperative to save the energy as much as possible. In this work, we propose energy efficient routing algorithm which is based on directed diffusion scheme. In the proposed scheme, some overloads required for reinforcing the gradient path can be effectively eliminated. Furthermore, in order to verify the usefulness of the proposed algorithm, several simulations are executed.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.127-128
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• 1992

• Korean Architects
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• s.578
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• pp.116-121
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• 2017

지난호에서는 2012년 가을학기 Harvard GSD의 Digital Media and Material Practice 수업의 일환으로 진행되었던 Diffusion Limited Aggregation System에 대하여 이야기를 시작했습니다. 먼저 유한 확산 집합체가 무엇인지를 자연에서 쉽게 발견할 수 있는 눈 결정의 현미경 사진을 통하여 알아 보았고 이 현상이 어떻게 일어나는 지에 대한 고찰을 통하여 유한 확산 집합체를 디지털 모형으로 생성하기 위한 밑그림을 그려보았습니다. 이번 회에서는 이를 디지털 모형으로 재구성했던 방법을 Visual Basic 을 통하여 단계별로 알아보도록 하겠습니다.

• Korean Architects
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• s.580
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• pp.118-123
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• 2017

지난 2회에 걸쳐서 2012년 가을학기 Harvard GSD의 Digital Media and Material Practice 수업의 일환으로 진행되었던 Diffusion Limited Aggregation System에 대하여 이야기를 시작 하였습니다. 먼저 유한 확산 집합체가 무엇인지를 자연에서 쉽게 발견할수 있는 예를 통하여 알아 보았고 이 현상이 어떻게 일어나는 지에 대한 고찰을 통하여 유한 확산 집합체를 디지털 모형으로 생성하기 위한 밑그림을 그려보았습니다. 이번 회는 저번회의 연장선상에서 유한 확산 집합체를 Visual Basic 을 사용하여 디지털 모형으로 재구성 하는 과정에 대하여 마져 이야기 하도록 하겠습니다.

• Journal of the Mineralogical Society of Korea
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• v.27 no.2
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• pp.85-95
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• 2014

The felsitic intrusives of Bulguksa granitic rocks of late Cretaceous in age are located at Mt. Daeduk, Daegu, where two different types of tourmalines are found. Two tourmalines show rounded and radiating in morphology and are found in separated region, but in same felsitic rocks. In this study, we investigate the chemical differences between two types of tourmaline and the effect of growing condition of the crystal on the its morphology. The rounded tourmaline has more amounts of Al and vacancy and less amounts of Ca, Na, K, Fe, Mn, Mg, which commonly occupy X and Y-site of the tourmaline. On the basis of the Diffusion-limited aggregation model, morphological irregularity indicates the active mobility of the magma. The radiating tourmaline, therefore, crystallized with active magma condition relatively, and the rounded tourmaline crystallized with stable magma condition created by decreasing temperature and the concentration of felsic components as the magma differentiate continually.