• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.791-793
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• 2009

Hydrogen has been recognized of the energy source for the future, in terms of the most environmentally acceptable energy source. A pressurized fluidized bed reactor made of carbon steel with 0.076 m I.D. and 1.0 m in height was employed for the thermocatalytic decomposition of methane to produce amount of $CO_2$ - free hydrogen with validity from a commercial point of view. The fluidized bed was proposed for withdrawing of product carbons from the reactor continuously. The methane decomposition rate with the carbon black N330 catalyst was rapidly reached a quasi-steady state and remained for several hour. The methane thermocatalytic decomposition reaction was carried out at the temperature range of 850 - 950 $^{\circ}C$, methane gas velocity of 2.0 $U_{mf}$ and the operating pressure of 1.0 -3.0 bar. Effect of operating parameters such as reaction temperature, pressure on the reaction rates was investigated and predicted the effect of a change in conditions on a chemical equilibrium thermodynamically, according to Le Chatelier's principle.

• Journal of the Korean Mathematical Society
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• v.53 no.4
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• pp.795-834
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• 2016

The main purpose of this paper is to propose a scheme of a proof of the nonsimpleness of the group $Homeo^{\Omega}$ ($D^2$, ${\partial}D^2$) of area preserving homeomorphisms of the 2-disc $D^2$. We first establish the existence of Alexander isotopy in the category of Hamiltonian homeomorphisms. This reduces the question of extendability of the well-known Calabi homomorphism Cal : $Diff^{\Omega}$ ($D^1$, ${\partial}D^2$)${\rightarrow}{\mathbb{R}}$ to a homomorphism ${\bar{Cal}}$ : Hameo($D^2$, ${\partial}D^2$)${\rightarrow}{\mathbb{R}}$ to that of the vanishing of the basic phase function $f_{\underline{F}}$, a Floer theoretic graph selector constructed in [9], that is associated to the graph of the topological Hamiltonian loop and its normalized Hamiltonian ${\underline{F}}$ on $S^2$ that is obtained via the natural embedding $D^2{\hookrightarrow}S^2$. Here Hameo($D^2$, ${\partial}D^2$) is the group of Hamiltonian homeomorphisms introduced by $M{\ddot{u}}ller$ and the author [18]. We then provide an evidence of this vanishing conjecture by proving the conjecture for the special class of weakly graphical topological Hamiltonian loops on $D^2$ via a study of the associated Hamiton-Jacobi equation.

• Journal of Information Processing Systems
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• v.1 no.1 s.1
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• pp.96-101
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• 2005

Spotlighted as an innovative information technology environment, ubiquitous computing has been actively researched on recently. Especially, domestic and global researches focus on the RFID system, which is being eyed to replace the existing bar-code system. As an essential technology for ubiquitous computing, the RFID system can be applied for various purposes. The security issues of the RFID system focus on how the low-priced tag type could have reasonable price competitiveness. The Auto-ID Center in the U.S. is spearheading the research on distribution service and omni-directional security. As for Japan, the researches on omni-directional security and EPC application are necessary in securing the technology for ubiquitous computing with support from the Ministry of Public Management Home Affairs, Posts, and Telecommunication. In this paper, a method of ensuring the availability of the RFID system service will be presented based on the ubiquitous computing environment with the existing omni-directional security and user-friendly interface. While the existing researches focus on the RF reader system and tag-based security, this paper's suggestion also considers the availability of a sen ice to suggest ways of increasing the practical usage of a low-priced RF tag.

• Journal of the Korea Concrete Institute
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• v.28 no.2
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• pp.235-244
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• 2016

This study was conducted to verify seismic performance of special moment frame's joints at roof-level with high-strength concrete and SD600 bars. K-RC-H was designed according to the seismic code and K-HPFRC-H had 150% of the original hoop spacing and 1.0% steel fiber volume fraction compared with K-RC-H. Both specimens had remarkable seismic performance without noticeable decrease in moment, but with very good energy dissipation before rebar failure. The U-bars in the joint sufficiently constrained rebar's action that pushed the cover upward. SD600 bars with $1.25l_{dt}$ had minimum slip in the joint. It was considered that the steel fiber contributed to improvement of the bending moment and joint shear distortion, and the result showed that it would be possible to increase the hoop spacing to 150% of the regular spacing.

• Cross-Cultural Studies
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• v.43
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• pp.79-113
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• 2016

This study aims to diachronically explore the women's movements in modern Japan by focusing on three key words, 'maternity,' 'suffrage,' and 'war,' in uncovering how these concepts relate to Japan as a state. In particular, this study sheds light on the policies toward women not from the perspective of the state, but rather from women's perspective and evaluates their expectations toward the 'state' thorough the activities of Fusae Ichikawa and $Raich{\bar{o}}$ Hiratsuka. Hiratsuka, who was devoted to establishing the 'state protection of maternity,' ended up casting away such expectations toward the state after the failure of the petition movement developed by the New Women's Association. On the other hand, Ichikawa, encouraged by the success of women's suffrage movement in the U.S., remained active in the petition movement in the hope of attaining female suffrage. Because of this, Ichikawa was more vulnerable to the requests by the national authorities for the cooperation in war efforts-event though most of her activities were contained within the redressing of everyday life issues. The expectations toward the 'state' was a principal driving force of women's movements in modern Japan, yet at the same time it was also the reason why-as purging of Ichikawa symbolizes-they came to be stigmatized with the promotion of invasive war.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.89-96
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• 2017

The CRISPR/Cas9 is a core technology that can result in a paradigm for breeding new varieties. This study describes in detail the sgRNA design, vector construction, and the development of a transgenic plant and its molecular analysis, and demonstrates how gene editing technology through the CRISPR/Cas9 system can be applied easily and accurately. CRISPR/Cas9 facilitates targeted gene editing through RNA-guided DNA cleavage, followed by cellular DNA repair mechanisms that introduce sequence changes at the site of cleavage. It also allows the generation of heritable-targeted gene mutations and corrections. Here, we present detailed procedures involved in the CRISPR/Cas9 system to acquire faster, easier and more cost-efficient gene edited transgenic rice. The protocol described here establishes the strategies and steps for the selection of targets, design of sgRNA, vector construction, and analysis of the transgenic lines. The same principles can be used to customize the versatile CRISPR/Cas9 system, for application to other plant species.

• Herbal Formula Science
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• v.16 no.2
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• pp.115-131
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• 2008

실험목적 : 빈소산은 11가지 생약으로 구성된 복합 한약 처방으로 관절염을 포함한 다양한 염증성 질환의 치료제로 사용되어 왔으나, 관절염에 대한 직접적인 효력평가는 찾아 보기 힘들다. 따라서 본 실험에서는 빈소산 추출물이 Freund's complete adjuvant (FCA)로 유발된 rat 류마티스성 관절염에 미치는 치료 효과를 dexamethasone (15mg/kg, 복강 투여) 의 효과와 비교 평가하였다. 실험방법 : 류마티스성 관절염은 FCA (10mg in 1ml paraffin oil 0.1ml/rats)를 좌측 후지에 피내 투여하여 유발하였다. 실험동물은 Wistar 랫트를 사용하였고, FCA 투여 14일 후 유사한 무릎관절 둘레를 나타내는 류마티스성 관절염 유발 rat와 정상 rat 및 실험군을 그룹당 9마리씩 나누었다. 실험동물은 100 또는 200mg/kg의 빈소산 추출물을 FCA 투여 14일 후부터 14일간 경구 투여하였으며, dexamethasone은 15mg/kg 농도로 복강 투여한 다음, 희생하여, 체중, 연골내 collagen 함량 및 chondroitin sulphate, heparin sulphate 및 hyaluronic acid와 같은 뼈내 glycosaminoglycan 함량의 변화를 각각 관찰하였다. 실험결과는 항염 효과가 이미 입증되어 있는 dexamethasone 15mg/kg 복강 투여군과 비교하였다. 결과 : FCA 투여는 현저한 체중, 연골내 collagen 함량 및 chondroitin sulphate, heparin sulphate 및 hyaluronic acid와 같은 뼈내 glycosaminoglycan 함량의 감소와 함께 유발 관절 둘레 및 조직내 prostaglandin $E_2$의 증가와 같은 전형적인 류마티스성 염증을 초래하였으나, 이러한 류마티스성 관절염 소견은 dexamethasone 및 모든 용량의 빈소산 추출물 투여에 의해 현저히 억제되었으며, 특히 빈소산 투여군에서는 투여 용량 의존적인 감소가 인정되었다. 결론 : 이상에서 빈소산 추출물은 투여 용량 의존적인 prostaglandin $E_2$ 억제를 매개하여 FCA 유발 류마티스성 관절염에 대한 치료 효과를 나타내는 것으로 관찰되었다. 따라서 새로운 관절염에 대한 치료제로서 개발 가능성이 있을 것으로 판단된다. 한편 빈소산 추출물은 주로 prostaglandin $E_2$ 억제작용에 의해 항염 효과를 나타내는 것으로 관찰되었으나, 금후 다른 작용기전에 대한 연구와 빈소산의 구성성분 중 유효 성분 규명을 위한 실험이 수행되어야 할 것으로 판단된다.

• The Journal of Engineering Geology
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• v.5 no.2
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• pp.193-200
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• 1995

It has been well known that the alkali-aggregate reaction between the aggregates and cement paste is one of the reasons of a concrete siructre expansion. Because of a serious demage on the concrete stnicture from the expansion, in many countries, the safety of the materials is checked in laboratory by mortar-bar test and the upper limit of expansion in length is 0.1%. The prescriptions are presented in the ASTM C227 and 490 of U.S. which has been international currency and in the KS Handbook F2503, F2546 and L5107 of Korea published by Korean Standards Association. Both of the prescriptions are almost same in their contents. Actually, in the process of preparing and measuring the mortar-bar according to the prescription mentioned above, it seems that there are no problems for its own purpose but a few points are found to be improved upon the methods to increase the accuracy for laboratory work as follows. 1. The prescription of blending ratio(aggregate, cement and water) should be noted by volume not by weight. 2. It is unreasonable to measure the initial length of mortar bars after 24$\pm$2 hours at once regardless the kind of aggregates. 3. It may bring about errors in calculating the expansion ratio under the condition of the denominator value fixed as 254mm. 4. The measuring methods of specific gravity are selected according to the purposes but the pure specific gravity displays the highest accuracy among them.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.2
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• pp.173-180
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• 2021

Purpose: The purpose of this study was to evaluate the retentive characteristics of the additional attachments used with implant bar attachment under repeated insertion/removal cycles. Materials and methods: The newly developed attachment and the commercially available attachment were investigated: ADD-Lock (AL), Locator blue (LB). Two fixtures were placed parallel to each other on the custom lower mounting, and patrix of each attachment was fixed to the fixture. Also, the matrix of each attachment was placed on the opposing upper mounting. A universal testing machine was used to measure the retentive force during initial, 100, 250, 500, 1000, 2000, and 2500 repeated insertion/removal cycles. Wear and deformation of the attachment s were observed by scanning electron microscopy (SEM). Mann-Whitney U test (α=.05) and wilcoxon signed-rank test (α=.05) were performed to compare retentive force between each group and before and after 2500 repeated insertion/removal cycles. Results: In terms of initial retentive force and retentive force after 2500 repeated insertion/removal cycles, the AL group (15.24 ± 1.46 N and 9.74 ± 1.16 N) showed significantly smaller values than the LB group (43.53 ± 12.39 N and 22.99 ± 4.77 N) (P<.05). Also, in the loss of retentive force, the AL group (5.50 ± 1.08 N, 36.08%) showed a smaller value than the LB group (20.54 ± 11.89 N, 47.19%) (P<.05). Based on SEM analysis, The AL group showed noticeable wear and deformation in the patrix and the LB group in the matrix. Conclusion: Locator showed a higher initial retentive force than newly developed attachment, while the loss of retentive force was also higher. Both additional attachments are considered to have sufficient retentive force after repeated insertion/removal cycles.

• The Journal of Korean Medical History
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• v.32 no.1
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• pp.63-76
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• 2019

The $S{\bar{u}}tra$ of Great Dhāraṇī of the Uṣṇīṣa-cittā is one of the most widely published scriptures of Esoteric Buddhism during the Goryeo and Joseon dynasty. The sutra is often referred to as a Buddhist medical scripture whose recitation is believed to allay diseases such as difficult birth, chest pain, and infectious and incurable diseases. It utilizes two major methods for healing: reciting and copying the sutra or copying the dharani and talisman which appear at the end of the text with fine cinnabar and ingesting them with aromatic water. In order to understand the medical and historical value of this sutra, this study examines the historical background of its establishment in early China and its migration to Korea in the Goryeo period. This study also investigates the identity and value of the scripture in Buddhist medical history. The oldest known printed texts of the sutra in Korea are dated to the late 11th century. Because of the material benefits of the text, the tradition of printing and distributing the sutra was very popular between the 13th and 19th centuries. Therefore, examples of the sutra having been used for medicinal purposes during rites are found in historical records. Finally, the study tries to identify the relationship between the treatment methods of the Sutra and those of Korean traditional medicine focusing on several Korean traditional medical texts such as the Hyangyak-Jibseongbang (Compilation of Native Korean Prescriptions), the Donguibogam, and the Euibang-Hapbu.