• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.31-34
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• 2002

HgTe quantum dots were synthesized in aqueous solution at room temperature by colloidal method. The synthesized materials were identified to be zincblende cubic structured HgTe quantum dots by X-ray diffraction and transmission electron microscopy image revealed that these quantum dots are agglomerate of a individual particle. The colloidally prepared HgTe quantum dots have the sphere-like shape with a diameter of approximately 4 nm. The optical properties of the HgTe quantum dots were investigated with photoluminescence(PL). The PL appears in the near-infrared region, which represent a dramatic shift from bulk HgTe behavior. The analytic results revealed that HgTe quantum dots have the broad size distribution, as PL emission spectrum covers the spectral region from 900 to 1400 nm. In this study, the factors affecting PL of HgTe quantum dots and particle size distributiont are described.會Ā᐀䁇?⨀젲岒Ā㰀會Ā㰀顇?⨀끩Ā㈀會Ā㈀?⨀䡪ఀĀ᐀會Ā᐀䡈?⨀Ā᐀會Ā᐀ꁈ?⨀硫ᜀĀ저會Ā저?⨀샟ගऀĀ저會Ā저偉?⨀栰岒ఀĀ저會Ā저ꡉ?⨀1岒Ā저會Ā저J?⨀惝ග؀Ā؀會Ā؀塊?⨀ග嘀Ā切會Ā切끊?⨀⣟ගĀ搀會Ā搀ࡋ?⨀큭킢Ā저會Ā저恋?⨀桮킢Ā저會Ā저롋?⨀⣅沥ࠀĀࠀ會Āࠀ၌?⨀샅沥Ā저會Ā저桌?⨀壆沥ሀĀ저會Ā저쁌?⨀o킢瀀ꀏ會Āᡍ?⨀棤좗ĀĀĀ會ĀĀ灍?⨀å좗ĀĀĀ會ĀĀ졍?⨀飥좗ĀĀĀ會ĀĀ⁎?⨀?ꆟᤀ

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.3
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• pp.38-49
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• 2015

This study aims to contemplated spatial recognition in Soswaewon Garden through garden visitors poetry. It was content analysis in poetry and extract frequency from words based on relationship of author. The results were as follows. First, relationship of authors who wrote Soswaewon Garden poetry was formed in companionship. In the Yang, San-Bo(梁山甫), poetry was written by Song, Soon(宋純), Kim, Un-Geo(金彦据) and Kim, In-Hu(金麟厚) as the central figure. Especially Kim, In-Hu was playing an important role in Soswaewon Garden poetry. He was wrote many of poetry and keep friends with Yang, Ja-Jeong(梁子渟) too. In the Yang, Ja-Jung, relationship of previous generation was sustained. In addition, Ko, Gyeong-Myeong(高敬命) and Kim, Seong-Won and Jeong, Chul(鄭澈) is more closely related than others. Because blood relationship by marriage. In the Yang, Jin-Tae(梁晋泰), He formed a relationship with a celebrity and attend to international activity. Since then Yang, Jin-Tae periord, Yang, Gyeong-Ji(梁敬之) and Yang, Chae-Ji(梁采之) formed relationship of previous generation was sustained. And surrounding people was written poetry as hold a banquet. Second, plant and ornament is a popular object for writing poetry. Bamboo grove and Fine tree with a high frequency of plant element in poetry. Bamboo grove is a typical species of trees in Soswaewon Garden. It was enclosed the Soswaewon Garden. Fine tree was often used target of poetry as a single tree. Meanwhile, ornament of the wall has been used most frequently. Descendants wrote a poem to see it because Kim, In-Hu's poetry was left. This phenomenon is involves respect for the ancient sages with high frequency. In addition, behavior of viewing the landscape was mainly appeared. Third, spatial recognition of Soswaewon Garden can be divided into landscape cognition, behavior cognition and emotional cognition. In a aspect of landscape cognition, early Soswaewon Garden was recognized as a pavilion. That was used garden name to 'Soswaewon Garden' since Yang, Ja-Jung's period. That is to say, Soswaewon Garden expanded from pavilion area surrounded by trees into the whole appearance is equipped garden area. Behavior cognition was consisting drink and enjoys a landscape. In the Yang, San-Bo, authors enjoyed drinking and viewing a landscape besides walking, writing poetry, viewing the moon. But after Yang, San-Bo's period other than drinking and enjoy a landscape has appeared a low frequency. These results were changed from internal place to blood relationship into external place to companionship. In the Yang, San-Bo's emotional cognition was sorrow and yearning about leave to Soswaewon Garden with an idly atmosphere. Pleasant emotion was sustained all generation. And emotion of respect for the ancient sages was appeared since Yang, Cheon-un.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.465-472
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• 2008

Fabrication of nanostructured materials and synthesis of nanomaterials have intensively studied to realize electronic devices for nanotechnology. By using nanoporous alumina mask, nanostructured material can be fabricated in the form of uniform array. The size and the density of the nanostructured materials can be controllable by changing the pore diameter and the density of the alumina mask. This method is possible low cost and on large scale process, and feasible to contribute the fusion technology consisting of information technology, nanotechnology, and biotechnology. Therefore, these techniques provide alternative approaches for development of new electronic applications. In this paper, the fabrication technique and its applications of nanoporous alumina mask are described and nanostructured materials such as quantum dots, nanoholes, and nanorods are introduced.

• Journal of Powder Materials
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• v.23 no.2
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• pp.143-148
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• 2016

A microfluidic reactor with computer-controlled programmable isocratic pumps and online detectors is employed as a combinatorial synthesis system to synthesize and analyze materials for fabricating CdSe quantum dots for various applications. Four reaction condition parameters, namely, the reaction temperature, reaction time, Cd/Se compositional ratio, and precursor concentration, are combined in synthesis condition sets, and the size of the synthesized CdSe quantum dots is determined for each condition. The average time corresponding to each reaction condition for obtaining the ultraviolet-visible absorbance and photoluminescence spectra is approximately 10 min. Using the data from the combinatorial synthesis system, the effects of the reaction conditions on the synthesized CdSe quantum dots are determined. Further, the data is used to determine the relationships between the reaction conditions and the CdSe particle size. This method should aid in determining and selecting the optimal conditions for synthesizing nanoparticles for diverse applications.

• Journal of the Korea Computer Graphics Society
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• v.17 no.1
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• pp.33-38
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• 2011

This paper proposes the method of image cartooning, that makes cartoon-like images of a target, using reference images. We deform a target image using pre-defined reference images. For this deformation, we extract feature points from the target image by Active Appearance Model(AAM) and apply the warping method to the target using feature points of target and feature points of reference image as a basis of warping function. We create simplified cartoon-like images by abstraction of the deformed target image and drawing of edges and quantization of luminance of the abstracted image. Two main concept of cartoon(exaggeration and simplification) is inhered in this method when we use a exaggerated cartoon image as a reference image. It is possible for this method to create various results by control of warping and change of reference image.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.476-477
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• 2013

반도체의 성능은 최근 10년 사이에 급격하게 발전했고 아날로그 및 디지털 회로 소자들에 있어 저전력/고속 특성 요구가 커지고 있다 [1]. 상온에서 30,000 $cm^2$/Vs 이상의 전자 이동도를 가지며 큰 conduction band offset을 갖는 InAs/AlSb 2차원전자가스(2DEG) 소자는 Spinorbit-interaction의 값이 매우 커서 SPIN-FET 소자로 크게 주목받고 있다 [2]. 본 발표자들은 GaAs 기판위에 성장한 InAs 2DEG HEMT 소자의 전/자기적인 특성과 고속반응 물질로 주목 받는 InSb 박막소자의 doping 특성에 따른 전기적/물리적인 특성의 평가에 대해 그 결과를 소개하고자 한다. 격자정합과 Semi-insulating 기판의 부재로 상용화되어 있는 GaAs와 InP 기판위에 물질차이에 따른 고유의 한계 특성을 줄이기 위한 Pseudomorphic이라 불리는 특별한 박막 성장 기법을 적용하여 높은 전자 이동도를 가지며 spin length가 길어 Spin-FET로서 크게 주목받고 있는 InAs 2DEG HEMT 소자를 완성시켰다. 60,000 ($cm^2$/Vs) 이상의 높은 전자 이동도를 갖는 소자의 구현을 목표로 연구를 진행하였으며 1.8 K에서 측정된 Spin-orbit interaction의 값은 6.3e-12 (eVm)이다. InAs/InGaAs/InAlAs 및 InGaAs/InAlAs 구조의 InP 기반의 소자에서 보다 큰 값으로 향후 Spin-FET 응용에 크게 기대하고 있다. 또한, GaAs 기판위에 구현된 InSb 소자는 격자부정합 감소를 위해 InAs 양자점을 사용하여 약 $2.6{\mu}m$ 두께로 구현된 InSb 박막 소자는 상온에서 약 60,400 ($cm^2$/Vs)의 상온 전자이동도를 보였으며 현재 동일 두께에서 세계 최고결과(~50,000 $cm^2$/Vs)에 비해 월등하게 높은 값을 보이고 있다. Hall bar pattern 공정을 거쳐 완성된 소자는 측정 결과 10~20% 이상 향상된 전자 이동도를 보였다. 2e18/$cm^3$ 미만의 p-doping의 경우, 상온에서 n-type 특성을 보이나, 저온에서 p-type으로 변하는 특성을 보였고 n-doping의 경우 5e17/$cm^3$까지는 전자 이동도만 감소하고, doping에 의한 효과는 크게 없었다. 1e18/$cm^3$의 높은 doping을 할 경우 carrier가 증가하는 것을 확인했다. 이상의 측정 결과로 Spin-FET 소자로서 아주 우수하다는 것을 확인할 수 있었고 n-/p- type이 특성을 고려한 high quality InSb 박막소자의 응용을 위한 중요한 정보를 얻을 수 있었다.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.3
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• pp.69-72
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• 2020

In this study, the inverted structured electroluminescence (EL) devices were fabricated with double electron transport layers (ETLs). The conduction band minimum (CBM) of TiO₂ NPs is lower than SnO₂ NPs. Therefore, it is expected that inserting TiO₂ NPs between the SnO₂ layer and the emission layer (EML) will reduce the energy barrier and transport electrons smoothly. The quantum dot light emitting diodes (QLEDs) with double ETLs showed the enhanced emission characteristics than those with only SnO₂ layer.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.3
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• pp.439-448
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• 2017

It is news from nowhere that post-quantum cryptography has side-channel analysis vulnerability. Side-channel analysis attack method and countermeasures for code-based McEliece cryptosystem and lattice-based NTRU cryptosystem have been investigated. Unfortunately, the investigation of the ring-LWE cryptosystem in terms of side-channel analysis is as yet insufficient. In this paper, we propose a chosen ciphertext simple power analysis attack that can be applied when ring-LWE cryptography operates on 8-bit devices. Our proposed attack can recover the key only with [$log_2q$] traces. q is a parameter related to the security level. It is used 7681 and 12289 to match the common 128 and 256-bit security levels, respectively. We identify the vulnerability through experiment that can reveal the secret key in modular add while the ring-LWE decryption performed on real 8-bit devices. We also discuss the attack that uses a similarity measurement method for two vectors to reduce attack time.

• Journal of Sensor Science and Technology
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• v.29 no.2
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• pp.105-111
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• 2020

Interest and demand for hydrogen sensors are increasing in the field of H₂ leakage detection during storage/transport/use and detection of H₂ dissolved in transformer oil for safety issues as well as in the field of breath analysis for non-invasively diagnosing a number of disease states for a healthy life. In this study, various ZnO-based sensors were synthesized by controlling the reduction in crystallite size, decoration of Pt nanoparticles, doping of electron donating atoms, and doping of various atoms with different ionic radii. The sensing response of the various prepared ZnO-based nanoparticles and quantum dots (QDs) for 10 ppm H₂ was investigated. Among the samples, the smallest-sized (3.5 nm) In³⁺-doped ZnO QDs showed the best sensing response, which is superior to those in previously reported hydrogen sensors based on semiconducting metal oxides. The higher sensing response of In-doped ZnO QDs is attributed to the synergic effects of the increased number of oxygen vacancies, higher optical band gap, and larger specific surface area.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.5
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• pp.1099-1112
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• 2018

The field of post-quantum cryptography (PQC) is an active area of research as cryptographers look for public-key cryptosystems that can resist quantum adversaries. Among those categories in PQC, code-based cryptosystem provides high security along with efficiency. Recent works on code-based cryptosystems focus on the side-channel resistant implementation since previous works have indicated the possible side-channel vulnerabilities on existing algorithms. In this paper, we recovered the secret key in HyMES(Hybrid McEliece Scheme) using a single power consumption trace. HyMES is a variant of McEliece cryptosystem that provides smaller keys and faster encryption and decryption speed. During the decryption, the algorithm computes the parity-check matrix which is required when computing the syndrome. We analyzed HyMES using the fact that the joint distributions of nonlinear functions used in this process depend on the secret key. To the best of our knowledge, we were the first to propose the side-channel analysis based on joint distributions of leakages on public-key cryptosystem.