• Applied Microscopy
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• v.24 no.1
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• pp.102-113
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• 1994

A thin section of the methanogenic archaebacterium, Methanoplanus limicola, shows that the surface glycoprotein array (S-layer) is separated from plasma membrane by a distinct inter-space, approximately 4.0-6.0nm wide. We report our structural study of the S-layer by electron crystallographic techniques. Image analysis and thin sections of the S-layer treated with and without triton disclosed that retention of the single layer crystal requires the presence of detergent to avoid hydrophobic bonding.

• Korean Journal of Poultry Science
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• v.24 no.1
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• pp.39-44
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• 1997

Two experiments were carried out to determine the effects of pelleting layer diets on the laying perforrnance and nutrients utilizability, using either 50-wk-old(Experiment 1) or 80-wk-old (Experiment 2) layers. There was no effect of pelleting layer diets on hen-day egg production and average egg weight but decreased (P<0.05) feed conversion ratio(intake /egg weight) in both experiments. Although both egg specific gravity and eggshell thickness were not influenced by pelleting eggshell breaking strength was improved(P<0.05) only in Experiment 1. Utilizability of dietary fat was improved(P<0.05) by pelleting layer diets with no difference in other nutrients utilizability. There was no difference in the passage rate of mash and pelleted layer diets.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.157-160
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• 2007

The catalyst layer of a proton exchange membrane (PEM) fuel cell is a mixture of polymer, carbon, and platinum. The characteristics of the catalyst layer play critical role in determining the performance of the PEM fuel cell. This research investigates the role of catalyst layer composition using a Central Composite Design (CCD) experiment with two factors which are Nafion content and carbon loading while the platinum catalyst surface area is held constant. For each catalyst layer composition， polarization curves are measured to evaluate cell performance at common operating conditions, Electrochemical Impedance Spectroscopy (EIS), and Cyclic Voltammetry (CV) are then applied to investigate the cause of the observed variations in performance. The results show that both Nafion and carbon content significantly affect MEA performance. The ohmic resistance and active catalyst area of the cell do not correlate with catalyst layer composition, and observed variations in the cell resistance and active catalyst area produced changes in performance that were not significant relative to compositions of catalyst layers.

• Geomechanics and Engineering
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• v.15 no.2
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• pp.739-744
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• 2018

This paper presents the results of numerical modeling studies on the effect of displacements of tunneling in granular soils. Presence of building loads is considered, to find displacement generated at the surface on tunnel. Effect of varying eccentricities of building is simulated, to find influence of building on vertical and horizontal displacement. Studies were carried out in two cases of with and without a geosynthetic layer installed at the bottom of the footing. Results of analysis revealed, the presence of geosynthetic layer under footing, with building placed on centre line, reduced the surface displacements compared to displacement generated without geosynthetic layer. Presence of geosynthetic layer under footing had a dominant effect in reducing displacements in high storey structures. However, when the building was shifted to greater eccentricities from centre line, presence of geosynthetic layer, led to insignificant reduction of displacements on the centre line at the surface.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.11.1-11.1
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• 2011

We have developed a simple synthetic method for fabricating a wafer-scale colloidal crystal film of 2D crystals in a 1D stack based on a combination of two simple processes : the self-assembly of polystyrene (PS) nanospheres at the water-air interface and the layer-by-layer (LbL) scooping transfer technique. The main advantage of this approach is that it allows excellent control of the thickness (at a layer level) of the crystals and the formation of a vertical crack-free layer over a wafer-scale (4 inch). We investigate the optical and morphological properties of the PhC multilayers fabricated using various mono-sized colloidal crystals (250, 300, 350, 420, 580, 720, and 850 nm), and mixed binary colloidal crystals (300/350 and 250/350 nm).

• Tribology and Lubricants
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• v.19 no.5
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• pp.245-250
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• 2003

Water is known to playa crucial role on friction of moving parts in nanoscale contact. Little is, however, known about the tribological behavior of a solid surface that is covered with water adsorption layer. The objective of this study is to investigate the nanotribological behavior of the water layer in relation to water affinity of the surface and relative humidity. This paper presents an examination of the frictional behavior of water adsorption layer as 'confined liquid film'. It is shown that the friction is inversely proportional to the hydrophilicity of surface and relative humidity. On the other hand, friction of hydrophobic surface is not influenced by relative humidity. A model is proposed for the water-mediated contact in which it is shown that the water layer between two hydrophilic surfaces with high relative humidity behaves as a lubricant.

• Applied Microscopy
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• v.46 no.3
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• pp.155-159
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• 2016

This paper analyses the relationship between the distribution of a dielectric layer on the apex of a metal field electron emitter and the distribution of electron emission. Emitters were prepared by coating a tungsten emitter with a layer of epoxylite resin. A high-resolution scanning electron microscope was used to monitor the emitter profile and measure the coating thickness. Field electron microscope studies of the emission current distribution from these composite emitters (Tungsten-Clark Electromedical Instruments Epoxylite resin [Tungsten/CEI-resin emitter]) have been carried out. Two forms of image have been observed: bright single-spot images, thought to be associated with a smooth substrate and a uniform dielectric layer; and multi-spot images, though to be associated with irregularity in the substrate or the dielectric layer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.2
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• pp.228-235
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• 2004

In this thesis, it is designed efficient electrode formation on the organic luminescent device. ITO electrode is treated with $O_2$plasma. In order to inject hole efficiently, there is proposed the shape of anode that inserted plasma polymerized films as buffer layer between anode and organic layer using thiophene monomer. It is realized efficiently electron injection to aluminum due to introduce the quantum well in cathode. In the case of device inserted the buffer layer by using the plasma poiymerization after $O_2$plasma processing for ITO transparent electrode, since it forms the stable interface and reduce the moving speed of hole, the recombination of hole and electronic ate made in the omitting layer. Compared with the devices without buffer layer, the turn-on voltage was lowered by 1.0(V) doc to the introduction of buffer layer Since the quantum well structure is formed in front of cathode to optimize the tunneling effect, there is improved the power efficiency more than two times.

• Journal of Environmental Science International
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• v.11 no.3
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• pp.201-207
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• 2002

This study was carried out to evaluate the artificial neural network algorithm for water quality forecasting in Chungju lake, north Chungcheong province. Multi-layer perceptron(MLP) was used to train artificial neural networks. MLP was composed of one input layer, two hidden layers and one output layer. Transfer functions of the hidden layer were sigmoid and linear function. The number of node in the hidden layer was decided by trial and error method. It showed that appropriate node number in the hidden layer is 10 for pH training, 15 for DO and BOD, respectively. Reliability index was used to verify for the forecasting power. Considering some outlying data, artificial neural network fitted well between actual water quality data and computed data by artificial neural networks.

• Journal of the Korea Society of Computer and Information
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• v.24 no.3
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• pp.19-27
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• 2019

This paper proposes a new method using multi-layer overlapped windows to improve the performance of YOLO network which is vulnerable to detect small dense objects. In particular, the proposed method uses the YOLO Network based on the multi-layer overlapped windows to track small dense vehicles that approach from long distances. The method improves the detection performance for location and size of small vehicles. It allows crossing area of two multi-layer overlapped windows to track moving vehicles from a long distance to a short distance. And the YOLO network is optimized so that GPU computation time due to multi-layer overlapped windows should be reduced. The superiority of the proposed algorithm has been proved through various experiments using captured images from road surveillance cameras.