• Journal of the Korean Electrochemical Society
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• v.8 no.4
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• pp.172-176
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• 2005

Recently, many researches on the high-voltage 5 V class cathode material have focused on $LiNi_{0.5}Mn_{1.5}O_4$, where $Mn^{3+}$ in the existing $LiMn_2O_4 (Li[Mn^{3+}][Mn^{4+}]O_4)$ is replaced by $Ni^{2+}(Li[Ni^{2+}]_{0.5}[Mn^{4+}]_{1.5}O_4)$ in order to utilize $Ni^{2+}/Ni^{4+}$ redox reaction in the 5V region. The partial substitution of Mn in $LiMn_2O_4$ for other transition metal element, $LiM_yMn_{1-y}O_4$(M=Cr, Al, Ni, Fe, Co, Cu, Ga etc) is known as a good solution to overcome the problems associated with $LiMn_2O_4$ like the gradual capacity fading. In this study, we synthesized $LiNi_{0.5}Mn_{1.5}O_4$ through a mechanochemical process and investigated its morphological, crystallographic and electrochemical characteristics. The results showed that 4 V peaks had been found in the cyclic volammograms of the synthesized powders due to the existence of $Mn^{3+}$ from the incomplete substitution of $Ni^{2+}$ for $Mn^{3+}$ implying that the mechanochemical activation alone was not good enough to synthesize an exact stoichiometric compound of $LiNi_{0.5}Mn_{1.5}O_4$. The synthetic condition of mechanochemical process, such as type of starting materials, ball-mill and calcination condition was optimized for the best electrochemical performance.

• Radiation Oncology Journal
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• v.20 no.1
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• pp.62-67
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• 2002

Purpose : This study was undertaken to analyze the efficacy and sphincter preservation rate of platinum based neoadjuvant chemotherapy Plus radiotherapy versus abdominoperineal resection and Postoperative radiotherapy for anal cancer. Materials and Methods : Data of forty-two patients with anal cancer were retrospectively analyzed. Among thirty-eight patients with epidermoid histology, four patients received radiotherapy, and nineteen patients received abdominoperineal resection and adjuvant radiotherapy with or without chemotherapy $(APR+RT{\pm}CT)$, and fifteen patients received neoadjuvant chemotherapy and radiotherapy (CRT). The CRT regimen was composed of three cycles of 5-fluorouracil $(1,000\;mg/m^2\;bolus\;on\;D1\~5)$ and cisplatin $(60\;mg/m^2\;bolus\;on\;D1)$ followed by 50.4 Gy to the tumor bed and regional lymphatics over 5.5 weeks. Both inguinal lymphatics were treated with an identical dose schedule. Residual disease was treated with an additional three cycles of identical adjuvant chemotherapy. An identical dose schedule was used for post-operative radiotherapy. Median follow-up period was eighty-five months. Results : Overall five-year survival rates were $80.3\%$, 88.9 and $79.4\%$ for entire patients, $APR+RT{\pm}CT$ group, and the CRT group, respectively. No significant difference was found between the two groups (p=0.49). Anus preservation rate for the CRT group was $86.7\%$. Age (0=0.0164) and performance status (p=0.0007) were found to be significant prognostic factors by univariate analysis. Age (p=0.0426), performance status (p=0.0008), and inguinal lymph node metastasis (e=0.0093) were statistically significant prognostic factors by multivariate analysis. No case of RTOG grade 3 complication or higher was reported. Conclusion : This and other recent studies have shown that combined chemotherapy plus radiotherapy for anal cancer results in a high rate of anal sphincter preservation as well as local control and survival. Furthermore, neoadjuvant use of chemotherapy with a cisplatin based regimen rather than a concurrent regimen may lead to a decrease in complications.

• Journal of Chest Surgery
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• v.40 no.12
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• pp.825-830
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• 2007

Background: Minimally invasive cardiac surgery appears to offer certain advantages such as earlier postoperative recovery and a greater cosmetic effect than that achieved through conventional sternotomy. However, this approach has not yet been widely adopted in Korea to replace complex open heart surgery such as mitral valve reconstruction. This study compared the results of robot assisted minimally invasive mitral valve repair with those results of conventional sternotomy. Material and Method: From December 1993 to December 2005, 520 consecutive patients underwent mitral valve reconstruction for mitral regurgitation in our institution. These patients were subdivided according to those whose surgery used the conventional sternotomy approach (Group S, n=432) and those who underwent minimally invasive right anterior thoracotomy (Group M, n=88); we then compared the clinical results of both groups. When we performed minimally invasive right thoracotomy, we used a robot (AESOP 3000) and made an incision less than 5 cm. Result: Our study patients in both groups were similar for their age, gender and preoperative ejection fraction. There were two hospital mortalities in group S. but there was no mortality in the group M patients. Significant reductions in the ICU stay and the postoperative hospital stay were observed in the group M patients compared with the group S patients. However, both the bypass time and the aortic cross-clamp time were significantly longer in the group M patients. In spite of the confined incision in the group M patients, there were no limitations on the mitral valve repair techniques. There was a similar frequency of postoperative significant residual mitral regurgitation in both groups. Conclusion: In this study, the minimally invasive mitral valve repair showed comparable early results with the conventional sternotomy patients. We will now need long-term follow-up of these patients who underwent minimally invasive mitral valve repair, but we anticipate that based on the results of this study, we will begin to routinely perform minimally invasive cardiac surgery as out primary approach for mitral valve reconstruction.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.10
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• pp.591-598
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• 2017

Power overshoot phenomenon was observed in microbial fuel cells (MFCs) used non-catalyzed graphite felt as cathode. Voltage loss in MFCs was mainly caused by cathode potential loss. Cheap stainless steel scrubber, which has high conductivity, and Pt/C coated graphite felt as cathode were used for overcoming power overshoot and reducing the cathode potential loss in MFCs. The MFCs used stainless steel scrubber showed no power overshoot even slow catholyte flow rate and produced 29% enhanced maximum current density ($23.9A/m^3$) than MFCs used non-catalyzed graphite felt while the power overshoot phenomenon was existed in Pt/C coated MFCs. Increasing catholyte flow rate resulted in disappearing power overshoot of MFCs used non-catalyzed graphite felt. In addition, maximum power density and current density of both MFCs used non-catalyzed graphite felt and stainless steel scrubber increased by 2-3.5 times. Cathode potential losses in all region of activation loss, ohmic loss, and mass transport loss were reduced according to increase of catholyte flow rate. Therefore, stainless steel scrubber has advantages that are economical materials as electrode and prevents power overshoot, leading to enhance electricity generation. In addition, increasing catholyte flux is one of great solution when power overshoot caused by cathodic overpotential is observed in MFCs.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.2
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• pp.127-136
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• 1994

Diffusional sampling devices offer many advantages for measuring concentration levels of industrial contaminants than the conventional pump and charcoal tubes because they are lightweight, require no power, pump or tubing. This study designed to evaluate and compare the sampling performance of passive sampler to charcoal tube from mixed organic solvent workplace with 181 organic solvent using workers working in different concentration of organic solvents. All study workers kept both devices in their breathing zone simultaneuosly in the workplaces, and the sampling analytical results were compared with those of charcoal tube. The results obtained are as follows: 1. The concentrations of toluene and xylene measured by passive sampler were slightly higher than those of charcoal tube, but there were no significant statistical differences between two methods. 2. The concentrations of MEK and cyclo-hexanone measured by passive sampler in low exposure workplace (below 0.20 of MEK TLV levels and 0.1 of cyclo-hexanone TLV levels) were about 2 times higher than that of charcoal tube sampling. While, absorption efficiency of passive sampler was reduced according to increasing concentration measurements of MEK and cyclo-hexanone in air. 3. The ratios of concentrations of toluene, xylene, MEK and cyc1o-hexanone measured by passive sampler over those measured by charcoal tube were 1.11, 1.07, 1.63 and 3.65 respectively. 4. The percentages of concentration of passive samplers within 0.75 and 1.25 of charcoal tube value as a reference value of 1.0 were 57% in toluene, 74% in xylene, 34% in MEK and 32% in cyclo-hexanone respectively. 5. The correlation coefficients of toluene, xylene, MEK and cyclo-hexanone between passive sampler and charcoal tube sampler were 0.963, 0.957, 0.943 and 0.562 with statistical significance.

• Korean Journal of Heritage: History & Science
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• v.53 no.1
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• pp.64-87
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• 2020

The cultural property management system of Korea was established based on the modern cultural assets acts and the old imperial estate management system enacted during the Japanese occupation. Academics have researched the cultural property management system oriented on the modern cultural assets acts, but few studies have been conducted into the old imperial estate management system, which is another axis of the cultural property management system. The old imperial estate was separated from the feudal capital by the Kabo Reform, but was dismantled during the colonial invasion of Japan and managed as a hereditary property of the colonial royal family during the Japanese colonial period. After establishment of the government, the Imperial Estate Act was enacted in 1954 and defined the estate as a historical cultural property managed by the Imperial Estate Administration Office. At this time, imperial estate property that was designated as permanent preservation property was officially recognized as constituting state-owned cultural assets and public goods in accordance with Article 2 of the Act's supplementary provisions during 1963, when the first amendment to the Cultural Property Protection act was implemented. In conclusion, Korea's cultural property formation and cultural property management system were integrated into one unit from two different sources: modern cultural assets acts and the old imperial estate property management system. If the change of modern cultural assets acts was the process of regulating and managing cultural property by transplanting and applying regulations from Japan to colonial Joseon, the management of the imperial estate was a process by which the Japanese colonized the Korean Empire and disposed of the imperial estate. Independence and the establishment of the government of the Republic of Korea provided the opportunity to combine these two different streams into one. Finally, this integration was completed with the establishment of the Protection of Cultural Properties Act in 1962.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.1-13
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• 2014

As part of reconsideration on naming of the scenic site No.1 "Myeongju Cheonghak-dong Sogumgang," this study attempts to identify whether there is any mistake with reference to place naming of Korea's No.1 scenic site and if so, to correct the problem by examining the origin of the name and its transition progress through analysis and interpretation of old maps, ancient documents such as traditional geographic books, Yusangi(遊山記) and Letters Carved on the Rocks. The findings of this study are as follows: In traditional geographic books, a term of 'Mt. Cheonghak(靑鶴山)' was first found from "SinjungDonggookyeojisungram(新增東國輿地勝覽)" and after a place name, 'Sogumgang(小金剛)' first appeared in "Yeojidoseo(輿地圖書)" in the middle of the 17th century, it was reproduced in "Jungsuimyeongji(增修臨瀛誌)", which was published in the early 20th century. However, as a result of analyzing old maps, the place name, Sogumgang cannot be found in any local or national map except place names such as Cheonghak-dong, Mt. Cheonghak and Temple Cheonghak. Even though 'Biseonam,' 'Cheonyudong,' 'Gyeongdam' and 'Mt. Cheonghak' appear in Yulgok's "Yucheonghaksangi(遊靑鶴山記)", any part in which 'Sogumgang' was referred is not found. Later, Cheonghak-dong Sogumgang seemed to had been called 'Mt. Cheonghak' or 'Cheonghak-dong(靑鶴洞)' for more than three centuries as seen in Lee Sun-il's "Godamilgo(孤潭逸稿)", Heo Geun's farewell records, Heo Mok's "Cheonghak-dong Guryongyeongi(靑鶴洞九龍淵記)", Yoon Sun-geo(尹宣擧)'s "Padongilgi(巴東日記)" and Lee Won-jo's letters and a poem composed by Gang Jae-hang in the middle of the 18th century is the only record in which the place name, 'Sogumgang' is shown. Meanwhile, 'Sogumgang' carved on Inung Rock(二能巖) in front of Temple Gumgang is presumed to be carved by Inunggyeoone(二能契員) in the 1870s or in 1930s, considering the size of each character, calligraphy, overall layout, wear extent and records in Jiriji. Therefore, no evidence can be found to say that each character of 'Sogumgang' was written by Yulgok because 'Sogumgang' has strong evidences of the origin of its place name. To sum up the findings stated above, since Yulgok's "Yucheonghaksangi", this place seems to have been referred as 'Mt. Cheonghak Cheonghak-dong' and as it is confirmed that the place name, 'Sogumgang' first appeared in "Ohyeongosijo(五言古時調)" of "Ibjaeseonsangyugo(立齋先生遺稿)" and "Yeojidoseo" in the middle of the 18th century, it can be inferred that the place name, Sogumgang had been partly mingled as an another name of Mt. Cheonghak. Therefore, even though it is difficult to say the existing place name has a significant problem, it is thought that it will be better to name 'Mt. Cheonghak Cheonghak-dong' rather than 'Cheonghak-dong Sogumgang' in order to stress on this place's traditional identity as a scenic site related to Yulgok. In addition, as confirmed in this study process, it is said that each character of place names, 'Mt. Cheonghak' and 'Gyeongdam(鏡潭)' and name 'Yoon Sun-geo' carved in Rock Sikdang stated in Yoon Sun-geo's "Padongilgi" in 1964 is a pledge showing the influence of "Yucheonghaksangi" as an ancient travel literature as well as a mark of the Giho school scholars' respect and spirit to honor Yulgok.

• Korean Journal of Cognitive Science
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• v.15 no.4
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• pp.1-14
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• 2004

When two objects are tying in the same visual direction there occurs abrupt depth change between two objects, which is against the assumption of the computational model for stereopsis on the surfaces in a natural scene. For this reason, this stimulus configuration is popularly used in the studies for the effectiveness of the constraints employed in the computational model. Contrary to the results from two nails (or objects) tying in the same visual direction, the two different surfaces from random-dot stereogram (RDS) in the same situation can be seen simultaneously in the different depth. The seemingly contradictory results between two situations my reflect the different strategies imposed by binocular mechanism for each situation during binocular matching process. Otherwise, the surfaces tying in the same visual direction is not equivalent situation to two objects tying in the same visual direction with regards to matching process. In order to examine above possibilities, the stereoscopic depth of the surface was measured after manipulating the visual direction of the surface elements. The visual direction of each dot pair from different surfaces in RDS (in Experiment 1) or the visual direction of line (hawing rectangle with regard to that of the vertical line (in Experiment 2) was manipulated. The stereoscopic depth of the surface was found to be varied depending on visual direction of the surface elements in both RDS and line hawing stimulus. Similar to the results from two nails situation depth of the surface was greatly reduced when each surface element was tying in the same visual direction as that of the other surface element or the other object. These results suggest that binocular mechanism imposes no different strategy in resolving correspondence problem in both two objects and two surfaces situation. And the results were discussed in the context of usefulness of the constraints employed in the computational model for stereopsis.

• Korean Journal of Biological Psychiatry
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• v.14 no.2
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• pp.115-121
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• 2007

Objetives : Identification of target genes for ethanol in neurons is important for understanding its molecular and cellular mechanism of action and the neuropathological changes seen in alcoholics. The purpose of this study is to identify of altered gene expression after acute treatmet of ethanol in rat gliom cells. Methods : We used high density cDNA microarray chip to measure the expression patterns of multiple genes in cultured rat glioma cells. DNA microarrays allow for the simultaneous measurement of the expression of several hundreds of genes. Results : After comparing hybridized signals between control and ethanol treated groups, we found that treatment with ethanol increased the expression of 15 genes and decreased the expression of 12 genes. Upregulated genes included Orthodenticle(Drosophila) homolog 1, procollagen type II, adenosine A2a receptor, GATA bindning protein 2. Downregulated genes included diacylglycerol kinase beta, PRKC, Protein phosphatase 1, clathrin-associated protein 17, nucleoporin p58, proteasome. Conclusion : The gene changes noted were those related to the regulation of transcription, signal transduction, second messenger systems. modulation of ischemic brain injury, and neurodengeneration. Although some of the genes were previously known to be ethanol responsive, we have for the most part identified novel genes involved in the brain response to ethanol.

• Sijohaknonchong
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• v.43
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• pp.177-206
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• 2015

This paper is written in order to research for the contents and expression of HanYongUn's Sijo. HanYongUn is very famous as monk and independent campaigner, modern poet in Korea. He wrote many kinds of literary works, for example, many modern poetry, modern novels, Sijo, Chino-Korean Poetry etc. It's very exceptional that he wrote a lot of Korean traditional Sijo and Chino-Korean Poetry. Because he was a many modern poet as same as modern novelist. So studying on his Sijo can help someone to understand the essence of HanYongUn's all literature. That's why I'm studying on HanYongUn's Sijo. The firstly, in aspect of the the contents of HanYongUn's Sijo, HanYongUn was expressing three kinds of themes, that is ideology, reality, daily life in his Sijo. The ideology consists of Buddhism and Confucianism and the reality is related with social conditions, the daily life is deeply connected with Nim. These features of his Sijo are different from his modern poetry and Chino-Korean Poetry which had a simple theme, for example, love with Nim, daily life. The secondly, in aspect of the expression of HanYongUn's Sijo, I studied the expression of HanYongUn's Sijo in three angles, that is, vocabulary and the developing of poet thinking, rhetorics. HanYongUn used essential words for expressing three kinds of themes effectively in his Sijo. And he was developing of his poet thinking by three steps in his Sijo. He applied several representative rhetorics to his Sijo, those are question and answer, exclamation, irony, distich etc. Even though I studied the characteristics of HanYongUn's Sijo in two aspects But there could be the other things to study about these kinds of theme. I might continue researching the other kinds of theme next time in the near future.