케이프 사이즈 벌크선 영업모델과 수익성에 관한 연구

정명국,금종수 한국항해항만학회 2020 한국항해항만학회 학술대회논문집 Vol.2020 No.춘계

케이프 사이즈 벌크선의 선박원가와 운용수입의 분석을 통해 각 영업모델의 수익성을 파악하여 사업성 여부를 확인 하는데 그 목적을 둠. 부가적으로 사업성 제고방안과 시사점을 도출하고 정책제언을 포함함.

Characteristics of Non-stoichiometric LiCoO2 depending on synthetic conditions

정명국,두재균,최청송 한국화학공학회 2007 화학공학의이론과응용 Vol.10 No.1

현재 이차전지의 양극물질로써 Lithium Cobalt Oxide가 가장 널리 쓰이고 있다. 그러나 기존의 Lithium 화합물(hydroxide, carbonate, oxide 등)과 Cobalt 화합물(hydroxide, carbonate, oxide 등)의 Solid State Reaction은 High Temperature-Long time의 Sintering condition으로 인해 Lithium Cobalt Oxide의 생산비용의 증가를 가져왔다. 이 실험에서는 여러 종류의 precursor와 그것의 합성조건들을 바꿔가며 그것들은 분석하여 비교함으로써 더 저렴한 비용의 생산과 높은 성능의 양극물질로써의 Lithium Cobalt Oxide의 합성 방법을 제시하고자 한다. 각각의 precursor들은 TGA, DSC의 열분석을 통해 precursor들의 Reaction의 특성이 비교되었으며 각각의 precursor로 합성된 Lithium Cobalt Oxide는 XRD, XPS, FTIR, Solid state NMR등의 분석을 통해서 가장 적합한 구조와 특성을 가진 Product를 찾는데 목적을 두고 연구가 진행되었다. 본 연구를 통해 Methanol을 이용한 precursor가 제조되었으며 이 Modified Solid State Reaction이 현재 가장 널리 쓰이고 있는 리튬 화합물과 코발트화합물의 Solid State Reaction을 보다 효과적으로 개선되어질 수 있음이 제시되었다.

침전법으로 제조된 전구체 성질에 의한 LiCoO₂의 특성에 관한 연구

정명국,황치석,최청송,Jeong, Myoung Kuk,Hwang, Chi Seok,Choi, Cheong Song 한국청정기술학회 2006 청정기술 Vol.12 No.2

본 연구에서는 수산화물 전구체로부터 HT-$LiCoO_2$ 분말을 제조하였다. 사용된 $Co(OH)_2$는 ${\alpha}$상 및, 또는 ${\beta}$ 상의 수산화물이며 여러 조건에서 침전법으로 제조되었다. 제조시에 $[OH^-]/[CO^{2+}]$ 농도 비와 숙성시간을 조절함으로써 원하는 특성을 지닌 $Co(OH)_2$ 제조가 가능하였다. 침전법으로 합성한 $Co(OH)_2$와 LiOH를 메탄올 수용액을 이용하여 혼합한 후 이어서 증발, 건조 그리고 숙성 조작에 의하여 HT-$LiCoO_2$의 전구체를 합성하였다. 숙성기간에 tailor-made ${\beta}$-phase $Co(OH)_2$는 CoOOH로 변환되면서 고용체를 형성한다. 이 같은 결과로 HT-$LiCoO_2$가 낮은 온도($600^{\circ}C$), 짧은 시간(10분)에 합성이 가능하게 된다. HT-$LiCoO_2$ powders were synthesized from hydroxide precursors in this study. The cobalt hydroxide compounds with hydrotalcite-like(${\alpha}$-phase) and/or brucite-like(${\beta}$-phase) structures as a component of the precursor were prepared in various PH conditions using precipitation method. It was found that various phase and compositions of cobalt hydroxides could be tailor-prepared via a careful control of preparation parameters such as the concentration ratio of $[OH^-]/[CO^{2+}]$ and aging time. The hydroxides $Co(OH)_2$ and LiOH were mixed with aqueous methyl-alcohol. The precursor of a HT-$LiCoO_2$ was synthesized via subsequent processes including evaporation, drying and aging. The transformation of tailor-made ${\beta}$-phase $Co(OH)_2$ to CoOOH and formation of solid solution in the precursor were achieved during aging. These results cause HT-$LiCoO_2$ to be synthesized at low temperature($600^{\circ}C$ ) for a short time(10min).

Protective Effect of Aqueous Extract from Erigeron annuus Against Cell Death Induced by Free Radicals

정명국,권혁진,주영돈,최고은,현경예 대한의생명과학회 2022 Biomedical Science Letters Vol.28 No.4

The extract of EA lacks studies showing its efficacy other than that it contains caffeic acid, an active compound that has antioxidant and neuroprotective effects on nerve cells. Therefore, in this study, we attempted to determine the effectiveness of EA extraction. In this study, we performed a DPPH assay to determine the antioxidant potential of EA. And then, the cytotoxic concentration of EA in HaCaT keratinocytes was determined, and the antioxidant effect was determined by measuring the malondialdehyde (MDA). The results of DPPH, a chemical antioxidant assay, clearly demonstrated the antioxidant capacity of EA extracted with distilled water. In addition, cell-based assays provide useful information on the protective effect of EA on oxidative stress-induced apoptosis.

공유수면매립의 적정성 평가를 위한 지표개발 및 지역특성분석

정명국,윤진숙 대한지리학회 2007 대한지리학회 학술대회논문집 Vol.- No.-

市販合成洗劑의 經皮急性 毒性에 관한 實驗的 硏究

徐大圭,金仁樹,丁明國 漢陽大學校 環境科學硏究所 1980 環境科學論文集 Vol.1 No.-

自國産 合成洗劑의 生體에 미치는 영향에 對해서는 該當國에서의 硏究가 徹底히 이루어지고 있음이 普通이나 우리나라에서는 國産洗劑의 이에 對한 硏究는 거의 없는 듯 하다. 本實驗은 國産合成洗劑의 經皮急性毒性에 對한 豫備試驗으로서 洗劑의 通常用途인 洗濯洗淨時 一次的 接觸이 일어나는 部位인 皮膚에 對한 直接塗布에 依해 惹起될 수 있는 極端의 變化를 觀擦하기 爲하여 市場에서 任意 選擇한 10餘種의 合成洗劑의 高濃度(原液, 50% 및 10%)溶液 2㎖을 mouse 背部皮膚(1㎝×2㎝ 넓이)에 反覆 塗布(4∼5時間 間隔으로 1日 3回)를 持續하였던 바 適用部位의 皮膚에 發赤과 艀腫이 生겼고 呼吸增大, 呼吸數減少, 自發運動減退, 立毛現象, 全身痙擊等의 症狀을 隨伴하였으며 結局은 mouse를 致死케 하였다. 死後의 病理組織 所見으로서는 塗布되였던 部位의 皮膚의 甚한 損傷과 充肝細胞質의 膨脹과 空胞, 腦組織의 充血 및 血管擴張 腎臟의 絲球體와 細尿管에서의 出血等을 認定할 수 있었다. 이와 같은 變化의 程度는 大體로 洗劑의 濃度에 比例되는 듯 하였다. 本實驗의 成編은 濃績은 濃厚 洗劑溶液의 持續的 塗布로서 惹起된 極端의 結果로서 一般的으로 使用되는 경우의 洗劑의 濃度나 皮膚와의 接觸時間과는 큰 差異가 있어 이것을 人體에 對한 毒性과 直接 관련시킬 수는 없을 것이다. 그러나 經皮毒性의 危險性을 排除할 수는 없고 經皮毒性에 關한 具題的인 細胞硏究와 洗劑使用에 있어서의 安全性確立에 必要한 對策樹立이 時急함을 强力히 市唆하는 結果라 思料된다. Although there is widespread national use of synthetic detergents, there is little data on the effects of these detergents in laboratory animals orin humans, with particular referenceto the Korean national. Most countries demand through investigation of any product sold on the market. An investigation not only of its acute effects, but also of the effects of its chronic use. This investigation was a preliminary study into the acute potential toxicity of the various synthetic detergents available on the market. By no means did the study attempt to be a definitive examination of these detergents, but merely attempted to point out the potential danger inherent in their uncontrolled use. Synthetic detergent, undiluted, and in concentration of 50 and 10 percent was used. 2㎖ of the detergent was applied directly to the back skin of mice over a 1×2㎝ area at 4-5 hour intervals, three times a day. Consecutive topical application leads to the decline and eventual death of the mice. The time interval required for death to occur decreased with increasing concentration, and varied with different products. Local redness and swelling of the skin and a syndrome characterized by increased depth and decreased rate in respiration, decreased spontaneous movement, pilomotor stimulation, and then generalized convulsions were observed before death occurred. Histopathological studies revealed remarkable skin changes in the area of the application. The skin injury included congestion. Swelling and vacuoles were observed in the liver cells, cerebral vasodilation and congestion was evident, and hemorrhage occurred in the renal glomeruli and tubules. As previously stated, there were preliminary results; the concentration used was much greate, and of more frequent and prolong application than generally used by the public, and therefore can give no real indication of the effect that synthetic detergent has on the human. However they do suggest that there is danger in the prolonged uncontrolled use of detergents. Therefore it is essential, as evident from this study, that considerable research into the potential dangers of detergents needs to be conducted.

법화수희찬게 (法華隨喜讚偈)

정명국사 불교사(불교) 1930 불교사 불교 Vol.74 No.-

침전법으로 제조된 전구체 성질에 의한 LiCoO₂의 특성에 관한 연구

정명국(Myoung Kuk Jeong),황치석(Chi Seok Hwang),최청송(Cheong Song Choi) 한국청정기술학회 2006 청정기술 Vol.12 No.2

腦動脈의 α-adrenaline性 受容體에 對한 藥理學的 硏究

丁明國,徐大圭 한양대학교 의과대학 1983 한양의대 학술지 Vol.3 No.1

The effects of alpha-adrenoceptor agonists, noradrenaline, phenylephrine and clonidine, and antagonists, coryn anthine yohimbine, on the postsynaptic alpha receptors were examined in the dog basilar, mesenteric and renal arteries and the following results were obtained: In the basilar artery, noradrenaline, phenylephrine and clonidine produced almost the same maximal contraction. Corynanthine(??M) had no effect on contractile responses induced by these agonists. Yohimbine (??M) inhibited the contractile responses to noradrenaline, phenylephrine and clonidine. In the mesenteric and renal arteries, the maximal responses to noradrenaline and phenylephrine were markedly greater than those to clonidine. Yohimbine (?? -?? M) and corynanthine (?? -?? M) both antagonized noradrenaline in these vessels. When the contraction induced by noradrenaline (?? M) were compared with those induced by KCl ( ??M) and serotonin (?? M) in the three kinds of arteries, the maximum response to noradrenaline in the basilar artery was much smaller than were produced by KCl or serotonin. In the mesenteric and renal arteries, however, noradrenaline produced contractions larger than those of KCl or serotonin. These results indicate that alpha receptors of dog basilar artery are largely alpha₂type or receptors which differ from classical postsynaptic alpha receptors.

최대용적률 구현을 위한 공동주택단지 특성분석

정명국(Joung Myung-Guk),박환용(Park Hwan-Yong) 대한국토·도시계획학회 2001 國土計劃 Vol.36 No.6

Floor area ratio has become one of most important factors in the of residential development feasibility study since there is no more developing land available and the legal floor area ratio of general residential land was dramatically decreased by the recent reform of city planning act from 400% to 250%. In this respect, this research attempted to find out the optimal level of site characteristics for the maximization of floor area ratio. Considering the variety of architectural and site legal requirements that changed period by period, we classified 830 sites larger than one hectare into four periods. Among them, sites developed in the second period are now under reconstruction and the third period adopted 250% floor area ratio which is now the ceiling of the ratio. The empirical result shows that primary factors increasing floor area ratio are building height, height difference between the lowest and highest, household density. On the other hand, site size and building number are the factors decreasing the ratio. Site characteristics of first three periods are found to be similar whereas the fourth period has wide coverage of the characteristics. However, increase in site size has minus effect on the floor area ratio after the first period.