• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.429-429
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• 2016

Organolead halide perovskite have attracted much attention over the past three years as the third generation photovoltaic due to simple fabrication process via solution process and their great photovoltaic properties. Many structures such as mesoporous scaffold, planar heterojunction or 1-D TiO2 or ZnO nanorod array structures have been studied to enhance performances. And the photovoltaic performances and carrier transport properties were studied depending on the cell structures and shape of perovskite film. For example, the perovskite cell based on TiO2/ZnO nanorod electron transport materials showed higher electron mobility than the mesoporous structured semiconductor layer due to 1-D direct pathway for electron transport. However, the reason for enhanced performance was not fully understood whether either the shape of perovskite or the structure of TiO2/ZnO nanorod scaffold play a dominant role. In this regard, for a clear understanding of the shape/structure of perovskite layer, we applied anodized aluminum oxide material which is good candidate as the inactive scaffold that does not influence the charge transport. We fabricated vertical one dimensional (1-D) nanostructured methylammonium lead mixed halide perovskite (CH3NH3PbI3-xClx) solar cell by infiltrating perovskite in the pore of anodized aluminum oxide (AAO). AAO template, one of the common nanostructured materials with one dimensional pore and controllable pore diameters, was successfully fabricated by anodizing and widening of the thermally evaporated Al film on the compact TiO2 layer. Using AAO as a scaffold for perovskite, we obtained 1-D shaped perovskite absorber, and over 15% photo conversion efficiency was obtained. I-V measurement, photoluminescence, impedance, and time-limited current collection were performed to determine vertically arrayed 1-D perovskite solar cells shaped in comparison with planar heterojunction and mesoporous alumina structured solar cells. Our findings lead to reveal the influence of the shape of perovskite layer on photoelectrical properties.

• Journal of Advanced Navigation Technology
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• v.22 no.1
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• pp.27-30
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• 2018

In this study, a 40 GHz band pass filter(BPF) employing a hair-pin structure has been designed, fabricated, and characterized for millimeter-wave wireless communication applications. Using the 3 dimensional(3-D) electromagnetic(EM) tool and design equations of the hairpin BPF, the BPF was desgned on the 5 mil-thick Duroid substrate(RT5880) with a relative dielectric constant (${\varepsilon}_r$) of 2.2. The tapping point (t) of the U-shape resonator in the input and output port has been determined using extracted an external Q-factor ($Q_e$). The coupling coefficients between the other resonators are calculated by adjusting the physical dimensions for the desired response of the BPF. The fabricated BPF was characterized using probing method on a probe station. Its measured center frequency(fc) and fractional BW are 41.6 GHz and 7.43 %, respectively. The measured return loss is below -10 dB at the pass band and the insertion loss is 3.87 dB. The fabricated BPF is as small as $9.1{\times}2.8mm^2$.

• The KIPS Transactions:PartB
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• v.15B no.6
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• pp.561-574
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• 2008

The spot detection phase of the 2-DE image analysis program segments a gel image into spot regions by an image segmentation algorithm and fits the spot regions to a spot shape model and quantifies the spot informations for the next phases. Currently the watershed algorithm is generally used as the segmentation algorithm and there are the Gaussian model and the diffusion model for the shape model. The diffusion model is closer to real spot shapes than the Gaussian model however spots have very various shapes and especially an asymmetric formation in x-coordinate and y-coordinate. The reason for asymmetric formation of spots is known that a protein could not be diffused completely because the 2-DE could not be processed under the ideal environment usually. Accordingly we propose an asymmetric diffusion model in this paper. The asymmetric diffusion model assumes that a protein spot is diffused from a disc at initial time of diffusing process, but is diffused asymmetrically for x-axis and y-axis respectively as time goes on. In experiments we processed spot matching for 19 gel images by using three models respectively and evaluated averages of SNR for comparing three models. As averages of SNR we got 14.22dB for the Gaussian model, 20.72dB for the diffusion model and 22.85dB for the asymmetric diffusion model. By experimental results we could confirm the asymmetric diffusion model is more efficient and more adequate for spot matching than the Gaussian model and the diffusion model.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.07a
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• pp.213-215
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• 2022

현재 게임들에서 Retro 풍이 일면서 다시 2D그래픽이 주목을 받고 있는 현상이 발생하고 있다. 물론 과거에도 2D 그래픽풍의 게임이 없었던 것은 아니나 근래에 들어서는 그 양상이 좀 더 진화되어 유저들에게 어필을 하고 있어 주목이 되고 있다. 현재 출시된 멀티 플랫폼 게임 엔진 중 게임 개발사에서 많이 사용 중인 엔진은 Unity3D 엔진이다. 본 논문에서는 Unity3D 엔진을 이용한 2D게임 그래픽 제작에 대해 논하고자 한다. 유니티 엔진은 C#, 자바스크립트로 코드를 작성할 수 있다는 이유로 C#과 모노 기반 코드로 개발되었다고 알려져 있었다. 실제로 엔진의 런 타임 부분은 C++과 마이크로소프트 닷넷 API, 에디터 프로그램은 C#으로 개발되었다. 스크립트는 유니티 내에서 바로 수정은 하지 못하고 Mono Develop등 유니티를 지원하는 스크립트 에디터에서 수정할 수 있다. 이에 본 논문에서는 멀티 플랫폼 게임 엔진을 이용한 2D 게임 그래픽인 Pixel Art 구현을 제안 하고자한다. 이를 통해서 다양한 멀티 플랫폼 기반의 게임 설계 및 개발에 도움이 되었으면 한다. 어떤 요소들이 2D게임을 선택하는 데에 있어 영향을 끼치는가에 대해서 알아보고, 세부항목에 따른 기본 도형을 이용한 게임 오브젝트 제작의 특징과 그 이유가 사용자에게는 어떤 의미를 가지는가에 대한 것을 알 수 있다.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.41-46
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• 2004

A breeding programme was initiated by utilizing a robust bivoltine breed CSR$_{18}$ and a polyvoltine breed Cambodge with the main objective of developing robust polyvoltine silkworm breeds/hybrids. At F$_1$ and F$_2$, parthenogenetic development was induced following warm water treatment of eggs at 46$^{\circ}C$ for 18 min followed by two backcrosses with Bl$_{67}$, an evolved polyvoltine breed. The newly developed breed was subjected for hybrid study using eight hybrid combinations in the laboratory at F$_{8}$ generation. F$_1$ hybrids between newly developed breed Bl$_{67}$ (Pg) and promising bivoltine breeds exhibited their superiority by expressing significant hybrid vigour for several economic characters like cocoon yield/10,000 larvae, cocoon weight, cocoon shell weight, cocoon shell ratio and denier. Study on cocoon shape variability revealed that cocoons of all the F$_1$ hybrids except BL$_{67}$ (Pg)${\times}$NB$_4$D$_2$ were found comparatively uniform in shape.pe.

• Progress in Superconductivity
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• v.11 no.1
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• pp.30-35
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• 2009

We have investigated the characteristics of a superconductive Pb shield for hemispherical shape and plate to improving signal-to-noise ratio(SNR) of biomagnetism. We measured the shielding factor for the position of helmet shape Pb and for changing the distance from Pb surface. To make a uniform magnetic field, a $1.5m{\times}1.5m$ set of the helmholtz coils activated at several frequencies. The shielding factor of hemispherical shape Pb was from 20 to 57 dB and of Pb plate was about $6{\sim}26dB$ as a function of distance from the lead surface. The shielding factor was rapidly reduced as increasing the distance from Pb surface. The white noise of superconductive quantum interference device(SQUID) with a superconductive shield was about $12fT/Hz^{1/2}$ at 1 Hz, $7fT/Hz^{1/2}$ at 100 Hz. The white noise was more increased about two times than conventional SQUID system without Pb shielding. An auditory signal was measured by first order gradiometer and magnetometer with Pb superconductive shield and compared the SNR. The SQUID system with Pb shield had better performance at low frequency noise level.

• Geomechanics and Engineering
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• v.13 no.6
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• pp.1045-1055
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• 2017

Tensile strength is considered key properties for characterizing rock material in engineering project. It is determined by direct and indirect methods. Point load test is a useful testing method to estimate the tensile strengths of rocks. In this paper, the effects of rock shape on the point load index of gypsum are investigated by PFC2D simulation. For PFC simulating, initially calibration of PFC was performed with respect to the Brazilian experimental data to ensure the conformity of the simulated numerical models response. In second step, nineteen models with different shape were prepared and tested under point load test. According to the obtained results, as the size of the models increases, the point load strength index increases. It is also found that the shape of particles has no major effect on its tensile strength. Our findings show that the dominant failure pattern for numerical models is breaking the model into two pieces. Also a criterion was rendered numerically for determination of tensile strength of gypsum. The proposed criteria were cross checked with the results of experimental point load test.

• Applied Science and Convergence Technology
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• v.27 no.4
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• pp.65-69
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• 2018

We studied the critical pressure characteristics of an anode type ion beam source driven by both charge repulsion and diffusion mechanism. The critical pressure $P_{crit}$ of the diffusion type ion beam source was linearly decreased from 2.5 mTorr to 0.5 mTorr when the gas injection was varied in 3~10 sccm, while the $P_{crit}$ of the charge repulsion ion beam source was remained at 3.5 mTorr. At the gas injection of 10 sccm, the range of having normal beam shape in the charge repulsion ion beam source was about 6.4 times wider than that in the diffusion type ion beam source. An impurity of Fe 2p (KE = 776.68 eV) of 12.88 at. % was observed from the glass surface treated with the abnormal beam of the charge repulsion type ion beam source. The body temperature of the diffusion type ion beam source was observed to increase rapidly at the rate of $1.9^{\circ}C/min$ for 30 minutes and to vary slowly at the rate of $0.1^{\circ}C/min$ for 200 minutes for an abnormal beam and normal beam, respectively.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.3
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• pp.7-12
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• 2007

Friction welding is a welding method to use frictional heat of a couple of materials. In this paper object is that design the welding part shape with the flow gallery part which there is no effect in flow. Decided the welding part design parameter and doing the friction welding analysis used the rigid-plastic FEM program DEFORM-2D. To do friction welding analysis must input necessary flow stress data, friction coefficient by temperature change, upset pressure and Revolution per minute etc. According to analysis result, it decided the optimal shape of welding part with no effect in flow.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.82-87
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• 1990

To investigate the shelf-life of the brick share improved Meju, the effect of the storage time and packaged storage on the quality of Meju and soy sauce were studied during 90 days storage at $30^{\circ}C$. During the storage period, pretense activity was rapidly increased, and it reached the maximum value after 30 days of storage and then decreased gradually with storage time. By the sensory evaluation, the soy sauce from Meju which was longer storage was increased its brown color but less sensory quality on taste and flavor. The sensory evaluation score of soy sauces were closely related to the value of protease activity of Meju, So, it was shown that the protease activity was also the major index component on the quality control for the brick shape improved Meju. The protease activity of brick shape Meju was lower during Meju making but decreased slowly during storage period than that of grain shape meju. The values of protease of Meju after 30 days storage were 359 (O.D. at 660 nm/g) in non-packaged, 349 in packaged Meju and after 180 days storage were 207,205, respectively. It was shown that the shelf-life of the brick shape improved Meju was about 180 days by the basis (protease activity: 200 O.D. at 660nm/g) for quality control from the grain shape Meju, and it was longer than that of grain shape Meju. It was also shown that the packaged storage did not prolong the shelf-life of the brick shape improved Meju.