• 한국토양비료학회지
• /
• 제44권6호
• /
• pp.1089-1094
• /
• 2011

주암호 상수원 상류지역인 송광천에 위치한 봉산 인공습지의 수생태학적 효율 향상을 위한 관리 방안을 제시하기 위하여 시기별, 처리단계별 및 오염물질 부하량별 수처리 효율을 평가하였다. 유입원수의 BOD, SS, T-N 및 T-P의 평균 함량은 $1.87mg\;L^{-1}$, $1.62mg\;L^{-1}$, $11.47mg\;L^{-1}$ 및 $4.40mg\;L^{-1}$이었으며, 연평균 처리효율은 BOD, SS, T-N 및 T-P가 각각 26%, 18%, 16% 및 9%로서 전반적으로 처리효율이 낮았으나 유입수 농도가 높아서 오염물질의 제거량은 매우 높은 편이었다. 인공습지 처리단계별 BOD, SS, T-N 및 T-P 변화를 조사한 결과는 모든 항목에서 침강지의 처리효율이 가장 높았고 BOD와 T-P는 습지 II > 습지 I, SS와 T-N은습지 I > 습지 II 순으로 처리효율이 높았다. 인공습지 구성 시스템별 오염물질 부하량에 따른 오염물질 처리량은 BOD는 침강지 > 습지 I > 습지 II, SS는 침강지 > 습지 II > 습지 I, T-N은 습지 I > 침강지 > 습지 II, T-P는 습지 II > 침강지 > 습지 I 순으로 높았다.

• 대한두경부종양학회지
• /
• 제15권2호
• /
• pp.141-148
• /
• 1999

Objectives: The development of thyroid tumor has a relationship with carcinogen, oncogene and tumor suppressor gene. With aminotriazole, radioactive iodine and nitrosomethylurea as carcinogens in rat, authors investigate the incidence in type of the thyroid tumors, p21 and p53 protein expression pattern by immunohistochemical stain and the relationship between the tumors and p21-p53 protein expressions. Materials and Methods: 80 experimental animals were divided into four groups; group 1(control, no carcinogen, n=20), group 2(oral administration of aminotriazole for 36 weeks, n=20), group 3(intraperitoneal injection of 131I for one time and oral administration of aminotriazole for 36 weeks, n=20), group 4(oral administration of nitrosomethylurea for 3 days and aminotriazole for 36 weeks, n=20). After 40 weeks they were sacrificed with pathologic examination and we performed immunohistochemical staining with pan-ras monoclonal antibody for p21 protein and CMI polyclonal antibody for p53 protein with paraffin-embedded specimens. Results: 1) No tumors were observed in group I, but 38.3% of nodular goiters, 11.7% of adenomas and 50.0% of carcinomas were observed in carcinogen treated groups(group 2, 3, 4). 2) The incidence of nodular goiter, adenoma and carcinoma were 70%, 20% and 10% in group 2, 40%, 15% and 45% in group 3 and 5%, 0% and 95% in group 4. 3) p21 protein was not expressed in normal thyroid tissues but was expressed in 26.1% of nodular goiters, 42.9% of adenomas and 6.7% of carcinomas. On the other hands, p53 protein was not expressed in normal thyroid tissues, nodular goiters, adenomas and in well differentiated thyroid carcinomas by immunohistochemical stain. Conclusion: The authors suggest that aminotrizole, 131I, nitrosomethylurea can be etiologic agents in the development of thyroid tumor and the p21 protein can be expressed in the early stage and in benign condition of thyroid tumor but p53 protein is not expressed in all conditions of development in rats.

• 한국인터넷방송통신학회논문지
• /
• 제15권3호
• /
• pp.149-154
• /
• 2015

본 논문은 안정된 결혼문제의 최적해를 쉽고 빠르게 찾는 알고리즘을 제안하였다. 첫 번째로, 남성의 여성 선호도와 여성의 남성 선호도 합 $p_{ij}$의 $n{\times}n$ 정방행렬로 변환시킨다. 두 번째로, 행렬에서 최대 반감도 (최악의 선호도)인 최대값 $_{max}p_{ij}$를 행 또는 열의 개수가 1개 ($|r_i|=1$ or $|c_j|=1$)가 존재할 때까지 삭제한다. 만약, $|r_i|=1$ or $|c_j|=1$이면 선택하고, 선택된 $p_{ij}$의 행 또는 열 값을 삭제한다. 이 과정을 ${\forall}(|r_i|=1{\cap}|c_j|=1)$가 될 때까지 반복 수행한다. 제안된 알고리즘을 7개의 안정된 결혼문제에 적용한 결과 간단하면서도 기존 알고리즘의 해를 개선하는 효과를 얻었다.

• 대한전자공학회논문지SD
• /
• 제39권10호
• /
• pp.25-34
• /
• 2002

본 논문에서는 코발트 실리사이드가 형성된 얕은 p+-n과 n+-p 접합의 전류-전압 특성을 분석하여 silicidation에 의해 형성된 Schottky contact 면적을 구하였다. 역방향 바이어스 영역에서는 Poole-Frenkel barrier lowering 효과가 지배적으로 나타나서 Schottky contact 효과를 파악하기가 어려웠다. 그러나 Schottky contact의 형성은 순방향 바이어스 영역에서 n+-p 접합의 전류-전압 (I-V) 동작에 영향을 미치는 것으로 확인되었다. 실리사이드가 형성된 n+-p 다이오드의 누설전류 증가는 실리사이드가 형성될 때 p-substrate또는 depletion area로 코발트가 침투퇴어 Schottky contact을 형성하거나 trap들을 발생시켰기 때문이다. 분석결과 perimeter intensive diode인 경우에는 silicide가 junction area까지 침투하였으며, area intensive junction인 경우에는 silicide가 비록 공핍층이나 p-substrate까지 침투하지는 않았더라도 공핍층 근처까지 침투하여 trap들을 발생시켜 누설전류를 증가시킴을 확인하였다. 반면 p+-n 다이오드의 경우 Schottky contact이발생하지 않았고 따라서 누설전류도 증가하지 않았다. n+-p 다이오드에서 실리사이드에 의해 형성된 Schottky contact 면적은 순방향 바이어스와 역방향 바이어스의 전류 전압특성을 동시에 제시하여 유도할 수 있었고 전체 접합면적의 0.01%보다 작게 분석되었다.

• 호남수학학술지
• /
• 제42권2호
• /
• pp.345-358
• /
• 2020

In this paper, we study the concepts of Wijsman lacunary invariant convergence, Wijsman lacunary invariant statistical convergence, Wijsman lacunary ${\mathcal{I}}_2$-invariant convergence (${\mathcal{I}}^{{\sigma}{\theta}}_{W_2}$), Wijsman lacunary ${\mathcal{I}}^*_2$-invariant convergence (${\mathcal{I}}^{\ast}^{{\sigma}{\theta}}_{W_2}$), Wijsman p-strongly lacunary invariant convergence ([W₂N_σθ]_p) of double sequence of sets and investigate the relationships among Wijsman lacunary invariant convergence, [W₂N_σθ]_p, ${\mathcal{I}}^{{\sigma}{\theta}}_{W_2}$ and ${\mathcal{I}}^{\ast}^{{\sigma}{\theta}}_{W_2}$. Also, we introduce the concepts of ${\mathcal{I}}^{{\sigma}{\theta}}_{W_2}$-Cauchy double sequence and ${\mathcal{I}}^{\ast}^{{\sigma}{\theta}}_{W_2}$-Cauchy double sequence of sets.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
• /
• pp.50-50
• /
• 2008

ZnO has been extensively studied for optoelectronic applications such as blue and ultraviolet (UV) light emitters and detectors, because it has a wide band gap (3.37 eV) anda large exciton binding energy of ~60 meV over GaN (~26 meV). However, the fabrication of the light emitting devices using ZnO homojunctions is suffered from the lack of reproducibility of the p-type ZnO with high hall concentration and mobility. Thus, the ZnO-based p-n heterojunction light emitting diode (LED) using p-Si and p-GaN would be expected to exhibit stable device performance compared to the homojunction LED. The n-ZnO/p-GaN heterostructure is a good candidate for ZnO-based heterojunction LEDs because of their similar physical properties and the reproducibleavailability of p-type GaN. Especially, the reduced lattice mismatch (~1.8 %) and similar crystal structure result in the advantage of acquiring high performance LED devices with low defect density. However, the electroluminescence (EL) of the device using n-ZnO/p-GaN heterojunctions shows the blue and greenish emissions, which are attributed to the emission from the p-GaN and deep-level defects. In this work, the n-ZnO:Ga/p-GaN:Mg heterojunction light emitting diodes (LEDs) were fabricated at different growth temperatures and carrier concentrations in the n-type region. The effects of the growth temperature and carrier concentration on the electrical and emission properties were investigated. The I-V and the EL results showed that the device performance of the heterostructure LEDs, such as turn-on voltage and true ultraviolet emission, developed through the insertion of a thin intrinsic layer between n-ZnO:Ga and p-GaN:Mg. This observation was attributed to a lowering of the energy barriers for the supply of electrons and holes into intrinsic ZnO, and recombination in the intrinsic ZnO with the absence of deep level emission.

• Journal of Electrical Engineering and information Science
• /
• 제2권5호
• /
• pp.65-71
• /
• 1997

We present heterojunction solar cells with a structure of metal/a-Si:H(n-i-p)/poly-Si(n-p)/metal for the terrestrial applications. This cell consists fo two component cells: a top n-i-p junction a-Si:Hi cell with wide-bandgap 1.8eV and a bottom n-p junction poly-Si cell with narrow-bandgap 1.1eV. The efficiency influencing factors of the solar cell were investigated in terms of simulation an experiment. Three main topics of the investigated study were the bottom cell with n-p junction poly-Si, the top a-Si:H cell with n-i-p junction, and the interface layer effects of heterojunction cell. The efficiency of bottom cell was improved with a pretreatment temperature of 900$^{\circ}C$, surface polishing, emitter thickness of 0.43$\mu\textrm{m}$, top Yb metal, and grid finger shading of 7% coverage. The process optimized cell showed a conversion efficiency about 16%. Top cell was grown by suing a photo-CVD system which gave an ion damage free and good p/i-a-Si:H layer interface. The heterojunction interface effect was examined with three different surface states; a chemical passivation, thermal oxide passivation, and Yb metal. the oxide passivated cell exhibited the higher photocurrent generation and better spectral response.

• Asian-Australasian Journal of Animal Sciences
• /
• 제2권3호
• /
• pp.533-534
• /
• 1989

• 대한화학회지
• /
• 제30권5호
• /
• pp.433-440
• /
• 1986

反陽性子性 溶媒인 dimethylsulfoxide中에서 p-nitrobenzeneazoresororcinol<4n-BAR>에 대하여 직류 폴라로그래피적 거동을 조사하였다. 0.05M $NaClO_4$의 DMSO溶媒中에서 4n-BAR은 1電子 2段階의 還元過程을 거쳐 hydrazo기를 포함하는 化合物로 還元된다. 還元反應의 中間 生成物은 比較的 反陽性子性 溶媒 속에서 安定하였다. 各 段階의 還元電流는 擴散支配的이었으며 一部 反應電流도 包含되었다. 酸을 添加함에 따라서 2個의 還元波가 하나로 合致되며 [acid]/[reductant]의 몰 (M)비가 M = 2인 條件에서 加電位(-E)에 대해 $log(i_d-i)(Mi_d/2-i)/i$/의 可逆性은 1電子 2段階 還元反應이고 非可逆的이었다.

• 대한수학회보
• /
• 제51권2호
• /
• pp.373-386
• /
• 2014

Let (R,m) be a commutative Noetherian local ring. In this paper we show that a finitely generated R-module M of dimension d is Cohen-Macaulay if and only if there exists a proper ideal I of R such that depth($M/I^nM$) = d for $n{\gg}0$. Also we show that, if dim(R) = d and $I_1{\subset}\;{\cdots}\;{\subset}I_n$ is a chain of ideals of R such that $R/I_k$ is maximal Cohen-Macaulay for all k, then $n{\leq}{\ell}_R(R/(a_1,{\ldots},a_d)R)$ for every system of parameters $a1,{\ldots},a_d$ of R. Also, in the case where dim(R) = 2, we prove that the ideal transform $D_m(R/p)$ is minimax balanced big Cohen-Macaulay, for every $p{\in}Assh_R$(R), and we give some equivalent conditions for this ideal transform being maximal Cohen-Macaulay.