• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.6
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• pp.231-234
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• 2003

ZnO thin films on (100) p-type silicon substrates have been deposited by pulsed laser deposition(PLD) technique using an Nd:YAG laser with a wavelength of 266nm. The influence of the deposition parameters, such as oxygen pressure, substrate temperature and laser energy density variation on the properties of the grown film, was studied. The experiments were performed for oxygen gas flow rate of 100~700 sccm and substrate temperatures in the range of 200~$500^{\circ}C$. We investigated the structural and morphological properties of ZnO thin films using X-ray diffraction(XRD), scanning electron microscopy(SEM) and atomic force microscopy(AFM).

• Carbon letters
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• v.12 no.2
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• pp.102-106
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• 2011

Carbon nanotubes (CNTs) have been synthesized by ferrocene-catalyzed pyrolysis of toluene. The influences of the experimental conditions on the morphology and microstructure of the product have been analyzed. To find the proper temperature for synthesis of CNTs, the experiment was performed in a temperature range from 800 to $1100^{\circ}C$. From content variation of ferrocene and thiophene as the catalyst, morphological change of carbon nanotubes has been observed. Also, the influence of the gas ratio of hydrogen and argon on the nanotube samples was analyzed by scanning electron microscopy and transmission electron microscopy.

• Korean Journal of Plant Resources
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• v.8 no.2
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• pp.127-133
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• 1995

Ginseng Folium has been used to cure acute gastritis, alcoholism and anemia. The morphological and anatomical characteristics of the leaf and stem of Panax ginseng C.A. Meyer cultivated in Korea for 1 to 6 years are described. It is found that the vessels increase in number and diameter, and also the vascular bundles increase in number, as the plant becomes old. The result showed that the commercial &In Sam Ip& samples on the markets of Pusan, Kumsan, Taegu and Seoul have been derived from the leaf and stem of 4 to 6 years old P. ginseng plants, most of them being 5-6 years old.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.150-150
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• 2003

wide bind gap과 wurtzite hexagonal structure를 가지고 있으며 청색 발광 및 청자색 레이저 특성을 보이는 III-V족 화합물반도체 GaN는 laser diodes (LD) 및 light emitting diodes (LED) 재료로 주목받고있는 주요 전자재료이다. 본 연구에서는 GaN를 chemical vapor deposition (CVD) 법을 이용하여 vapor-liquid-solid (VLS) mechanisum에 의하여 GaN나노와이어 형태로 성장시켰다. 기판은 (001)Si을 사용하였고 suputtering을 이용하여 GaN와 AlN의 double buffer layer (DBL)를 증착시켰으며 촉매로는 Ni을 사용하였다. 또한, 원료로는 고순도 Ga금속과 NH$_3$ gas를, carrier gas로는 Ar을 사용하여 GaN/AlN/(001)Si 위에 GaN 나노와이어를 성장시켰다. 성장된 GaN 나노와이어는 DBL의 두께, Ga source의 양, 튜브 안의 압력, 튜브 안의 위치 등의 제 공정변수에 따라 tangled, straight 등의 다양한 형상을 보였으며 지름은 약 30~100 nm, 길이는 수 $\mu\textrm{m}$로 관찰되었다. GaN나노와이어의 결정성, 형상 및 발광특성 등을 x-ray diffraction (XRD), photoluminesence (PL), scanning electron microscope (SEM), transmision electron microscope (TEM) 등을 이용하여 측정하였으며 제 공정변수와의 상관관계를 규명하였다.

• Animal Systematics, Evolution and Diversity
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• v.33 no.4
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• pp.256-261
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• 2017

Eucephalobus oxyuroides (de Man, 1876) Steiner, 1936 belonging to the family Cephalobidae Filpijev, 1934 (Cephalobomorpha) is newly reported from South Korea. This species is distinguished from other Eucephalobus species by its pointed tail terminus, high lips and relatively longer female tail and body. From many previous studies, intraspecific variation in this species has been reported for body length, absence/presence of probolae, and number/position of papillae in the posterior region of male, posing an obstacle for identification and phylogenetic analysis. In this study, details of the morphological characters and morphometric of E. oxyuroides Korean population are described and illustrated based on optical microscopy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.1030-1033
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• 2002

ZnO thin films on (100)p-type silicon substrates have been deposited by pulsed laser deposition(PLD) technique using an Nd:YGA laser with a wavelength of 266nm. The influence of the deposition parameters, such as oxygen pressure, substrate temperature and laser energy density variation on the properties of the grown film, was studied. The experiments were performed for substrate temperatures in the range of $200{\sim}500^{\circ}C$ and oxygen pressure in the range of $10^{-2}{\sim}10^2mTorr$. We investigated the structural, morphological and optical properties of ZnO thin films using X-ray diffraction(XRD), atomic force microscopy(AFM), photoluminescence(PL).

• Imaging Science in Dentistry
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• v.46 no.3
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• pp.217-222
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• 2016

Bifid mandibular condyle (BMC) is an uncommon morphological variant of the mandibular condyle. Although authors have proposed various etiologies for BMC, no consensus has emerged. In addition, varying findings have been reported regarding the epidemiological parameters of BMC (e.g., prevalence, gender ratio, and age), possibly due to its low incidence. BMC is occasionally associated with symptoms of the temporomandibular joint, such as ankylosis, pain, and trismus; however, it is difficult to detect this condition on conventional radiographs. This study reports a case of BMC with radiographic findings, and reviews the literature on the epidemiology of BMC.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.6B
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• pp.1012-1020
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• 2000

In this paper, This paper presents a new algorithm which is used for detecting and extracting human masks from a color still image. The regions where each pixel has a value of skin-color were extracted from the Cb and Cr images, after the tone of the color image is converted to YCbCr from. A morphological filter is used to eliminate noise in the resulting image. By scanning it in horizontal and vertical ways under ways under threshold value, first candidate section is chosen. If it is not a face, secondary candidate section is taken and is divided into two candidate sections. The proposed algorithm is not affected by the variation of illuminations, because it uses only Cb and Cr components in YCbCr color format. Moreover, the face recognition was possible regardless of the degree of shifting face, changed shape, various sizes of the face, and the quality of image.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1432-1435
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• 2005

We report failure mode observed in polymer EL blue devices, relating with life curve. The modes are analyzed by observing compositional and morphological variation using TEM-EDX, STM, and reverse engineering method as destructive ways, and also investigated mobility changes of hole and electron by measuring transient EL as a nondestructive way corresponding to life curve. We believe that the postulated failure modes in polymer EL devices can present right directions to obtain better performance, especially life time, of polymer devices in material and device structural designing points of view.

• ALGAE
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• v.20 no.1
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• pp.15-23
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• 2005

Polysiphonia pacifica is rhodomelaceous red algal species that includes five varieties in Pacific Ocean: P. pacifica var. delicatula, P. pacifica var. distans, P. pacifica var. determinata, P. pacifica var. disticha, and P. pacifica var. gracilis. We here report morphology and phylogeny of P. pacifica to confirm the relationships among previously described varieties as a loan of type specimens from US and to assess phylogenetic relationships of closely related species using plastid protein-coding rbcL gene. Polysiphonia pacifica is distinguished by having creeping filaments attached by unicellular rhizoids not cut off by cross walls, four pericentral cells, ecorticate, trichoblasts rare, ultimate branchlets attenuate at the tip but not pungent, and tetrasporangia in long straight series in the ultimate branchlets. The protein-coding plastid rbcL gene sequence data show that P. pacifica is distinctly different from the superficially similar species, P. morrowii and P. stricta. However, the rbcL sequences of P. pacifica var. pacifica and var. disticha are identical though they have morphological variation.