• 전자공학회논문지
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• 제51권4호
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• pp.101-109
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• 2014

임의의 물체 영상에서 정확한 윤곽선을 찾아내는 것은 영상 처리 관련 시스템을 구축하는데 있어 필수적인 요소이다. 특히, 자동화된 생산 공정에서 생산품의 검사를 위한 비전시스템을 구축하다면 직선, 원 등의 정형화된 모형에 대한 윤곽선의 검출이 매우 중요하다. 본 논문에서는 원형(prototype) 에너지를 추가하여 개선된 윤곽선 추출 알고리즘으로 원형적응 동적윤곽선 모델, p-Snake를 제안한다. 제안 방법은 원형분석을 위하여 물체 영상에 소벨 연산을 수행한 후, 기존 스네이크 알고리즘을 적용하여 초기 윤곽선을 찾는다. 이후 초기 윤곽선 정보에 근거하여 직선, 원 등의 원형(prototype)을 분석하고, 원형 에너지를 정의하여 기존의 스네이크 함수에 추가적인 에너지 항목으로 사용함으로써 물체의 최종 윤곽선을 검출하였다. 산업현장의 배경을 가정한 환경에서 취득된 340장의 영상에 대하여 실험한 결과, 잡음이나 조명 등의 이유로 물체와 배경의 구분이 선명하지 않거나 영상에서 에지가 충분히 존재하지 않는 경우에도 윤곽선을 추출할 수 있음을 확인할 수 있었다. 또한 원형(prototype)과 얼마나 일치하는 가를 나타내는 척도인 유사도의 경우, 제안한 p-ACM으로 추출한 윤곽선의 원형 유사도가 ACM의 처리 결과에 비해 9.85%가량 우수한 것으로 나타났다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권6호
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• pp.438-444
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• 2021

Objectives: Loss of the interdental papilla is multi-factorial and creates a multitude of problems. Autogenous connective tissue/biomaterial-based regeneration has been attempted for decades to reconstitute the black space created due to the loss of papilla. The aim of this present study was to regenerate papillary recession defects using an amnion-chorion membrane (ACM) allograft and to evaluate the clinical outcome up to six months postoperatively. Materials and Methods: Twenty patients with 25 Nordland and Tarnow's Class I/II interdental papillary recession defects were treated with ACM and coronal advancement of the gingivo-papillary unit via a semilunar incision on the labial aspect followed by a sulcular incision in the area of interest. A photographic image analysis was carried out using the GNU Image Manipulation software program from the baseline to three and six months postoperatively. The black triangle height (BTH) and the black triangle width (BTW) were calculated using the pixel size and were then converted into millimeters. The mean and standard deviation values were determined at baseline and then again at three and six months postoperatively. The probability values (P<0.05 and P≤0.01) were considered statistically significant and highly significant, respectively. An analysis of variance and post hoc Bonferroni test were carried out to compare the mean values. Results: Our evaluation of the BTH and BTW showed a statistically and highly significant difference from the baseline until both three and six months postoperatively (P=0.01). A post hoc Bonferroni test disclosed a statistically significant variance from the baseline until three and six months postoperatively (P<0.05) and a non-significant difference from three to six months after the procedure (P≥0.05). Conclusion: An ACM allograft in conjunction with a coronally advanced flap could be a suitable minimally invasive alternative for papillary regeneration.

• 대한수학회지
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• 제46권3호
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• pp.589-607
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• 2009

In this paper we study arithmetically Cohen-Macaulay (ACM for short) vector bundles $\varepsilon$ of rank k $\geq$ 3 on hypersurfaces $X_r\;{\subset}\;{\mathbb{P}}^4$ of degree r $\geq$ 1. We consider here mainly the case of degree r = 4, which is the first unknown case in literature. Under some natural conditions for the bundle $\varepsilon$ we derive a list of possible Chern classes ($c_1$, $c_2$, $c_3$) which may arise in the cases of rank k = 3 and k = 4, when r = 4 and we give several examples.

• KSBB Journal
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• 제11권1호
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• pp.65-70
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• 1996

본 연구에서는 글루콘산 및 그 유도체 생산에 관 한 기초자료를 얻기 위하여 일차적으로 글루콘산나 트륨의 생산조건에 대하여 실험하였다. 발효가 진행 됨에 따라 생성되는 글루콘산을 수산화나트륨을 이 용하여 중화시킴으로써 글루콘산나트륨으로 전환하였으며 이때 초기 당농도 및 pH의 영향을 정량적으 로 검토하여 생산성을 비교하였다. Aspergillus niger를 이용한 글루콘산나트륨 발효 에서 초기 농도 및 초기 pH가 발효 특성치에 미치 는 영향은 실험 결과를 종합하면 최대비생성속도는 초기 당농도 110g/$\ell$ 에서 $0.20hr^{-1}$로서 가장 높은 값을 나타내였으며 균체 빛 글루콘산나트륨 수율은 저농도 기질인 당놓도 26/$\ell$. 에서 0.24, 0.49로서 최대값을 나타내였고 잔당 농도는 5g/$\ell$. 미만이었다. 또한 총괄 글루콘산나트륨 생산성은 고농도 기질인 11Og/$\ell$에서 1.18g/$\ell$/hr로서 가장 높았다. 그리고 발효를 위한 최척 pH는 5.5이었다. 산업체 발효조 척용, 간헐 첨가 회분배양(intermittent feeding fed-batch)의 결과, 36시간 경과 후의 글루콘산나트륨 의 농도는 255g/l 이였으며 산업적 생산이 가능한 수준이었다.

• Journal of Pharmaceutical Investigation
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• 제23권3호
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• pp.155-163
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• 1993

Inclusion complexation of 1,7,21,27-tetraaza[7.1.7.1]paracyclophane (CPM 55) with 2,7-dihydroxynaphthalene (2,7-DHN) or 1,3-dihydroxynaphthalene (1,3-DHN) in pD 1.17 $DCl-D_2O$ solution was investigated by $^1H$ nuclear magnetic resonance spectroscopy (NMR) using 4,4'-dimethylaminodiphenylmethane (ACM 11) as an acyclic analog of CPM 55. In CPM 55-naphthalene derivative complex, alkyl protons located in the cavity of CPM 55 were shown to be subjected to anisotropic shielding and protons of naphthalene moiety shifted remarkably to upfield. However, in ACM 11-naphthalene derivative systems, chemical shifts for protons of both DHN compounds were not significant. The remarkable chemical shift changes suggested that the naphthalene moiety of 2,7-DHN or 1,3-DHN was included in the hydrophobic cavity of CPM 55 in aqueous solution. From the continuous variation plots of induced chemical shifts of 2,7-DHN, it was found that 2,7-DHN was included in the cavity of CPM 55 at 1:1 molar stoichiometry. Both computer simulation of a inclusion complex and strong upfield chemical shift changes of 2,7-DHN protons supported the conformation of pseudoaxial inclusion as the presumed geometry of the host-guest complex.

• 대한수학회보
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• 제59권4호
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• pp.929-949
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• 2022

Given an ACM set 𝕏 of points in a multiprojective space ℙ^m×ℙⁿ over a field of characteristic zero, we are interested in studying the Kähler different and the Cayley-Bacharach property for 𝕏. In ℙ¹×ℙ¹, the Cayley-Bacharach property agrees with the complete intersection property and it is characterized by using the Kähler different. However, this result fails to hold in ℙ^m×ℙⁿ for n > 1 or m > 1. In this paper we start an investigation of the Kähler different and its Hilbert function and then prove that 𝕏 is a complete intersection of type (d₁, …, d_m, d'₁, …, d'_n) if and only if it has the Cayley-Bacharach property and the Kähler different is non-zero at a certain degree. We characterize the Cayley-Bacharach property of 𝕏 under certain assumptions.

• 대한수학회지
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• 제56권5호
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• pp.1355-1370
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• 2019

A curve $X{\subset}\mathbb{P}^r$ has maximal rank if for each $t{\in}\mathbb{N}$ the restriction map $H^0(\mathcal{O}_{\mathbb{P}r}(t)){\rightarrow}H^0(\mathcal{O}_X(t))$ is either injective or surjective. We show that for all integers $d{\geq}r+1$ there are maximal rank, but not arithmetically Cohen-Macaulay, smooth curves $X{\subset}\mathbb{P}^r$ with degree d and genus roughly $d^2/2r$, contrary to the case r = 3, where it was proved that their genus growths at most like $d^{3/2}$ (A. Dolcetti). Nevertheless there is a sector of large genera g, roughly between $d^2/(2r+2)$ and $d^2/2r$, where we prove the existence of smooth curves (even aCM ones) with degree d and genus g, but the only integral and non-degenerate maximal rank curves with degree d and arithmetic genus g are the aCM ones. For some (d, g, r) with high g we prove the existence of reducible non-degenerate maximal rank and non aCM curves $X{\subset}\mathbb{P}^r$ with degree d and arithmetic genus g, while (d, g, r) is not realized by non-degenerate maximal rank and non aCM integral curves.

• E2M - 전기 전자와 첨단 소재
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• 제7권3호
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• pp.243-251
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• 1994

ITO(Indium Tin Oxide) film with thickness of 1500.angs. was prepared by an e-beam evaporator onto a glass and a p-type InP wafer (100) LEC grown Zn-doped p=2.3*10$\^$16/cm$\^$-3/), in which the components of ITO used for evaporation source were hot pressed pellets 1 mole% ln$\_$2/O$\_$3/+9 mole% SnO$\_$2/, and evaporated in O$\_$2/ ambient. The optimum conditions to preparation of ITO thin film were the substrate temperature of 350.deg. C, the injected oxygen pressure of 2*10$\^$-4/ torr, and the evaporation speed of 0.2-0.3.angs./sec, respectively. In these optimum conditions, the resistivity and the carrier concentration were 5.3*10$\^$-3/ .ohm.-cm, 6.5*10$\^$20/cm$\^$-3/, and the transmittance was over 80%. From the results of J-V measurements in ITO/p-InP structure solar cells, the higher pressure of injected oxygen, the more open circuit voltage. The efficiency of ITO/p-InP solar cell without the grid line contact, prepared by the optimum evaporation conditions, was 7.19%. By using the grid line contact, the efficiency, the open circuit voltage, the short circuit current density, the fill factor, the series resistance, and the shunt resistance were 8.5%, 0.47V, 29.48 mAcm$\^$-2/ , 61.35%, 3.ohm., and 26.6k.ohm., respectively.

• 한국세라믹학회지
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• 제32권3호
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• pp.371-377
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• 1995

Silicon oxide films were grown on single-crystal silicon substrates at low temperatures (25~205$^{\circ}C$) in a low pressure electron cyclotron resonance (ECR) oxygen plasma. The growth rate of the silicon oxide film increased as the temperature increased or the pressure decreased. Also, the thickness of the silicon oxide film increased at negative bias voltage, but not changed at positive bias voltage. The growth law of the silicon oxide film was approximated to the parabolic form. Capacitance-voltage (C-V) and current density-electric field (J-E) characteristics were studied using Al/SiO2/p-Si MOS structures. For a 10.2 nm thick silicon oxide film, the leakage current density at the electric field of 1 MVcm-1 was less than 1.0$\times$10-8Acm-2 and the breakdown field was higher than 10 MVcm-1. The flat band voltage of Al/SiO2/p-Si MOS capacitor was varied in the range of -2~-3 V and the effective dielectric constant was 3.85. These results indicate that high quality oxide films with properties that are similar to those of thermal oxide film can be fastly grown at low temperature using the ECR oxygen plasma.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.181-185
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• 2004

Electrokinetic bioremediation was conducted on phenanthrene-contaminated soil to study the effects of soil temperature and pH on microbial population and removal efficiency at different current densities from 0.63 to 3.13 mA cm$^{-2}$ . Microorganism used in the biodegradation of phenanthrene was Sphingomonas sp. 3Y, which was isolated from a diesel-contaminated site. The microorganism was successfully penetrated into the contaminated soil by electrokinetic phenomena and the highest microbial population was observed in the middle region of soil specimen where soil pH was near neutral. Therefore, phenanthrene removal occurred mainly at anode and middle parts of soil specimen due to a relatively high microbial population. Also, the highest removal efficiency of 68.8% was obtained at 1.88 mA cm$^{-2}$ while low degradation was detected at 3.13 mA cm$^{-2}$ . It was presumably because the soil temperature at 1.88 mAcm$^{-2}$ was close to the appropriate temperature of about 30'c while the temperature increase to above 45$^{\circ}C$ at 3.13 mA cm$^{-2}$ inhibited the microbial activity severely.