• 한국재료학회지
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• 제26권12호
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• pp.704-708
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• 2016

The unique characteristics of graphene make it an optimal material for crucial studies; likewise, its potential applications are numerous. Graphene's characteristics change with the number of total layers, and thus the rapid and accurate estimation of the number of graphene layers is essential. In this work, we review the methods till date used to identify the number of layers but they incorporate certain drawbacks and limitations. To overcome the limitations, a combination of these methods will provide a direct approach to identify the number of layers. Here we correlate the data obtained from Raman spectroscopy, optical microscopy images, and atomic force microscopy to identify the number of graphene layers. Among these methods, correlation of optical microscopy images with Raman spectroscopy data is proposed as a more direct approach to reliably determine the number of graphene layers.

• Applied Biological Chemistry
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• 제41권6호
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• pp.426-430
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• 1998

Danish pastry 제조 공정에서 Pastry 마가린 함량과 결 수 변화가 Danish pastry의 품질을 결정하는 완제품의 수분 함량, 굽기 손실, 부피, 경도, maximum weight, 및 vapor action에 미치는 영향을 조사하였다. 제품의 수분함량은 동일한 pastry 마가린 함량에서 결 수가 증가할 수록 미세한 증가를 보였고 동일한 결 수에서 pastry 마가린의 함량이 증가할 수록 제품의 수분 함량은 감소하였다. 제품의 굽기 손실은 동일한 pastry 마가린 함량에서 결 수가 증가할 수록 감소하였고, 동일한 결 수에서 pastry 마가린 함량이 증가할수록 제품의 굽기 손실은 증가하였다. 부피의 경우 30%에서는 18결, 50%에서는 27결, 70%에서는 36결, 90%, 110%에서는 48결이 최대의 부피를 얻었다. 경도와 maximum weight는 동일한 결 수에서 pastry 마가린 함량이 증가할 수록 감소하였고 동일한 pastry 마가린 함량에서 결 수가 증가할 수록 경도와 maximum weight는 감소하였다. Vapor action크기가 $9{\sim}16\;mm,\;17{\sim}24\;mm$부근 일 때 제품의 부피가 가장 크고 vapor action수와 부피는 비례하였다. 제품의 상품화에 가장 적합한 vapor action크기는 $9{\sim}24\;mm$가 가장 적절한 것으로 나타났다.

• 한국전자통신학회논문지
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• 제14권6호
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• pp.1153-1160
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• 2019

본 논문에서는 CNN의 컨볼루션 레이어 개수 및 커널의 크기와 개수가 CNN에 어떠한 영향을 끼치는지 실험을 통해 알아보기 위해 진행하였다. 또한 분석을 위해 일반적인 CNN도 실험하여 실험에 사용된 CNN과 비교하였다. 분석에 사용될 신경망들은 CNN을 기반으로 하며 각각의 실험모델들은 레이어 개수, 커널의 크기 및 개수를 일정한 값으로 고정해 실험을 진행하였다. 모든 실험에는 2계층의 완전연결계층을 고정으로 사용하였다. 다른 변수들은 모두 동일한 값을 주어 실험하였다. 분석결과 레이어의 수가 작을 경우 커널의 크기 및 개수와 상관없이 데이터의 분산 값이 작아 견고한 정확도를 보여주었다. 레이어의 수가 커질수록 정확도도 증가됐으나 일정 수치 이상부턴 오히려 정확도가 내려갔으며 분산 값도 커져 정확도 편차가 크게 나타났다. 커널의 개수는 다른 변수보다 학습속도에 큰 영향을 끼쳤다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.273.1-273.1
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• 2014

Graphene, a two dimensional plane structure of $sp^2$ bonding, has been promised for a new material in many scientific fields such as physics, chemistry, and so on due to the unique properties. Chemical vapor deposition (CVD) method using transitional metals as a catalyst can synthesize large scale graphene with high quality and transfer on other substrates. However, it is difficult to control the number of graphene layers. Therefore, it is important to manipulate the number of graphene layers. In this work, homogeneous solid solution of Cu and Ni was used to control the number of graphene layers. Each films with different thickness ratio of Cu and Ni were deposited on $SiO_2/Si$ substrate. After annealing, it was confirmed that the thickness ratio accords with the composition ratio by X-ray diffraction (XRD). The synthesized graphene from CVD was analyzed via raman spectroscopy, UV-vis spectroscopy, and 4-point probe to evaluate the properties. Therefore, the number of graphene layers at the same growth condition was controlled, and the correlation between mole fraction of Ni and the number of graphene layers was investigated.

• 한국컴퓨터정보학회논문지
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• 제21권1호
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• pp.1-8
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• 2016

Convolutional neural network (CNN) consists of a few pairs of both convolution layer and subsampling layer. Thus it has more hidden layers than multi-layer perceptron. With the increased layers, the size of convolution mask ultimately determines the total number of weights in CNN because the mask is shared among input images. It also is an important learning factor which makes or breaks CNN's learning. Therefore, this paper proposes the best method to choose the convolution size and the number of layers for learning CNN successfully. Through our face recognition with vast learning examples, we found that the best size of convolution mask is 5 by 5 and 7 by 7, regardless of the number of layers. In addition, the CNN with two pairs of both convolution and subsampling layer is found to make the best performance as if the multi-layer perceptron having two hidden layers does.

• 한국식품과학회지
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• 제34권6호
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• pp.935-940
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• 2002

Puff pastry의 제조 공정에서 pastry 마가린 함량과 적층 수의 변화가 puff pastry의 품질을 결정하는 색도 변화, 경도 변화, 저장중 경도 변화, 품질 평가 및 관능 검사에 미치는 효과를 조사하였다. 동일한 pastry 마가린 함량에서 적층 수가 증가할수록 껍질의 백색도 값의 변화는 다소 감소하였고 적색도 값은 70%, 81결에서 $16.8{\pm}2.3$으로, 황색도 값은 256결의 각 pastry 마가린 함량에서 26.0 내외의 높은 경향이었다. 그리고 속의 변화는 큰 차이가 없었다. 동일한 pastry 마가린 함량에서 경도는 110%, 144결에서 $839.6{\pm}75.6g$으로 가장 낮았다. 동일한 pastry 마가린 함량이 증가할수록 저장 기간에 따른 경도의 증가폭은 감소하는 경향이었다. pastry 마가린 함량이 70%에서는 256결의 제품을, 90% 함량에서는 144결과 256결의 제품을, 110%에서는 81결과 144결의 제품을 선택하여 관능검사를 한 결과는 90%, 144결이 맛과 식감에서 유의적인 차이가 1% 수준에서 우수하게 나타났다. 따라서 pastry 마가린 함량에 적절한 적층 수를 선택하는 것이 맛, 향, 식감이 양호한 제품을 제조하는데 중요하다는 사실을 알 수 있었다.

• Computers and Concrete
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• 제26권5호
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• pp.377-384
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• 2020

A two-dimensional particle flow cod (PFC) is used to study the effect of missile impact on the concrete target. For this purpose firstly calibration of numerical model was performed so that tensile strength of numerical models and experimental sample were the same. Secondly, a concrete model was built. The number of concrete layers and the angle of concrete layers related to horizontal axis were changed. Their numbers were 1, 2, 3 and 4. The angles were 0°, 15°, 30°, 45°, 60°, 75° and 90°. A semi-circle missile was simulated at top of the concrete layers. Its velocity in opposite side of Y direction was 100 m/s. three measuring circles were situated at the below the missile in the model to receive the applied force. The load in the missile and measuring circles together with failure pattern were registered at the beginning of the impaction. The results show that concrete layers number and concrete layers angle have important effect on the failure load while the failure pattern was nearly constant in all of the models.

• 한국CDE학회논문집
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• 제10권6호
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• pp.421-431
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• 2005

This paper introduces a new approach for saving build time of hybrid rapid prototyping by decomposing a part into minimum number of layers. In the hybrid rapid prototyping, a part of a complicated shape is realized by adding layers of a simpler shape, each of which is obtained by machining a sheet of constant thickness from its top and bottom surfaces. Thus it is desired to decompose a given part into the minimum number of layers while guaranteeing each layer to be fabricated from the given sheets using a 3-axis milling machine. To satisfy these requirements, a concave edge-based algorithm is proposed to decompose a part into layers by considering the tool accessibility, the total number of layers, and the allowable sheet thickness.

• Korean Journal of Mathematics
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• 제30권2호
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• pp.361-362
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• 2022

It is shown that the p-part of the class number of the lower layers of a cyclotomic ℤ_p-extension can grow exponentially.

• Geomechanics and Engineering
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• 제14권2호
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• pp.115-129
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• 2018

This paper presents a set of results of plate load tests that imposed incremental cyclic loading to a sandy soil bed containing multiple layers of granulated rubber-soil mixture (RSM) at large model scale. Loading and unloading cycles were applied with amplitudes incrementally increasing from 140 to 700 kPa in five steps. A thickness of the RSM layer of approximately 0.4 times the footing diameter was found to deliver the minimum total and residual settlements, irrespective of the level of applied cyclic load. Both the total and residual settlements decrease with increase in the number of RSM layers, regardless of the level of applied cyclic load, but the rate of reduction in both settlements reduces with increase in the number of RSM layers. When the thickness of the RSM layer is smaller, or larger, settlements increase and, at large thicknesses may even exceed those of untreated soil. Layers of the RSM reduced the vertical stress transferred through the foundation depth by distributing the load over a wider area. With the inclusion of RSM layers, the coefficient of elastic uniform compression decreases by a factor of around 3-4. A softer response was obtained when more RSM layers were included beneath the footing damping capacity improves appreciably when the sand bed incorporates RSM layers. Numerical modeling using "FLAC-3D" confirms that multiple RSM layers will improve the performance of a foundation under heavy loading.