• 대한건축학회논문집:구조계
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• 제35권9호
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• pp.199-206
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• 2019

Experimental study on the durability characteristics to examine the feasibility of concrete with high water-tightness and self-healing performance to minimize maintenance of concrete for artificial ground is as follows. 1) When blending agent, swelling agents, and curing accelerator were added on the ternary system cement with blast-furnace slag fine particles and fly ash to give a self-healing property, higher blending strengths by 82% at design standard strength of 24MPa and by 74% at design strength of 30MPa, respectively could be obtained. 2) The permeability test for the specimens having high water-tightness and no shrinkage showed that the permeability was reduced at maximum of 98%. However, the permeability was decreased as the design strength was increased, showing the reduction rate of 87% at the design strength of 50MPa. 3) The depth of carbonation of blast-furnace slag and fly ash was increased in all the specimens compared with those of OPC only. However, as the material age was increased, carbonation penetration depth was decreased compared with the reference blend. 4) Compared with the reference blending using only OPC, the freeze-thaw resistance was higher in the case of blending with 40% of blast-furnace slag and 10% of fly ash at the design standard strength of 50MPa. In addition, the freeze-thaw resistance in general was superior in the design standard strength of 50MPa with the lower water-binder ratio (W/B) as compared with the design standard strength of 24MPa and 30MPa with the high water-binder ratios.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.29-32
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• 2005

It is recognised that a permeability waterproof agent have been extensively used for concrete, in these days. In present paper shows effective practical scheme of a permeability waterproof agent in construction market that is to develope durability of concrete structure as apply to job site through the examination physical and chemical property of a permeability waterproof agent. It is indentified that can be maintain waterproofing performance, moreover it makes satisfactory result of permeation resistance as applying siliceous waterproof agent.

• Composites Research
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• 제17권4호
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• pp.40-46
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• 2004

본 연구에서는 single lap 전단시험을 통해 자가치료제와 촉매의 혼합비율 및 경화온도가 자가치료용 폴리머 복합재에 적용되는 자가치료제의 접착성능에 미치는 영향을 조사하였다. 자가치료세로는 DCPD (dicyclopentadiene), ENB(5-ethylidene-2-norbornene), DCPD와 ENB가 혼합된 경우를 고려하였으며 촉매로는 bis(riclohexylphosphine) benzyllidine rethenium (IV) dichloride Grubbs' catalyst를 사용하였다. 이때 DCPD에 대한 촉매의 혼합비율은 1.0wt%와 0.5wt%, ENB에 대한 촉매의 혼합비율은 0.lwt%, DCPD와 ENB의 혼합액에 대한 촉매의 혼합비율은 0.5wt%를 적용하였으며 경화온도는 $25^{\circ}C$, $60{\circ}C$, $80^{\circ}C$를 고려하였다. 연구결과에 따르면 DCPD의 경우 안정화된 접착강도를 얻기 위해서는 많은 양의 촉매와 긴 경화시간이 요구되었다 ENB의 경우는 DCPD의 경우에 비해 촉매의 혼합비율이 낮아도 빠른 경화반응을 얻을 수 있었지만 경화시간이 증가함에 따라 접착전단강도는 DCPD와는 달리 최대 값에 도달하였다가 점차 감소하면서 안정화되는 양상을 나타내었다. DCPD와 ENB의 혼합액 경우도 ENB와 유사한 경화거동을 나타내며 DCPD에 대한 ENB의 혼합비율이 높을 수록 경화반응이 빨라지는 양상을 얻을 수 있었다. 아울러 경화온도가 높을수록 집착전단강도는 증가되며 안정화된 평탄부에 도달하는 경화시간은 짧아짐을 알 수 있었다

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1668-1673
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• 2008

고분자 복합재 구조물의 경우 일반적으로 여러 층의 단층(laminar)이 적층된 구조로 이루어져 있으며, 모재균열, 층간분리 및 섬유파단과 같은 손상이 발생되어 파단에 이르게 된다. 자가손상 복구기법은 복합소재의 열경화성 수지 내에 손상복구액을 포함하고 있는 마이크로캡슐과 촉매를 투입하여 외부의 도움 없이 손상을 치료할 수 있는 방법으로, 소재의 디자인에 있어서 새로운 페러다임을 제공할 수 있는 것으로 현재 많은 연구가 진행되고 있다. 본 연구에서는 ENB(5-ethylidene-2-norbornene)와 DCPD(dicyclopentadiene)에 대하여 DMA(dynamic mechanical analysis)와 DSC(differential scanning calorimetry)를 이용하여 특성을 분석하였다. 또한 그들의 ROMP(ring-opening metathesis polymerization)반응과의 관계를 조사하였으며, ENB와 DCPD 블렌드에 대한 복구액으로서의 특성도 조사하였다. 본 연구실에서 합성된 두 가지 다른 종류의 ROMP 경화제에 대한 실제 자가손상복구에으로서의 적용상 특성도 연구하였다.

• 한국정밀공학회지
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• 제31권4호
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• pp.287-295
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• 2014

Smart manufacturing (SM) considered as a new trend of modern manufacturing helps to meet objectives associated with the productivity, quality, cost and competiveness. It is characterized by decentralized, distributed, networked compositions of autonomous systems. The model of SM is inherited from the organization of the living systems in biology and nature such as ant colony, school of fish, bee's foraging behaviors, and so on. In which, the resources of the manufacturing system are considered as biological organisms, which are autonomous entities so that the manufacturing system has the advanced characteristics inspired from biology such as self-adaptation, self-diagnosis, and self-healing. To prove this concept, a cloud machining system is considered as research object in which internet of things and cloud computing are used to integrate, organize and allocate the machining resources. Artificial life tools are used for cooperation among autonomous elements in the cloud machining system.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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• pp.169-172
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• 2003

Manufacturing process for autonomic microcapsules was introduced and autonomic microcapsules were manufactured by varying with various manufacturing process variables. Urea-formaldehyde resin was used for the wall of microcapsules and DCPD (dicyclopentadiene) was used for the self-healing agent. The characteristics of these microcapsules was evaluated through a particle size analyaer, an optical microscope, and a TGA. The various manufacturing process variables, such as pH and agitation speed of the emulsified solution, were considered to focus in this study. According to the results, the particle size distributions were affected on the agitation speed of the emulsified solution, and the thermal stability was influenced by pH of the emulsified solution.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2004년도 추계학술대회
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• pp.259-268
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• 2004

유비쿼터스환경으로 발전하기 위하여 네트웍을 구성하는 시스템들의 문제나 장애의 자가 진단 및 치유에 대한 요구가 높아지고 있다. 본 논문에서는 이러한 유비쿼터스환경에서 여러 시스템들이 스스로 자신의 오류나 문제를 관찰, 진단하고 치유할 수 있는 자가치유 시스템을 제안한다. 특히, 제안 시스템은 기존의 자가 치유시스템에서 연구되어왔던 일률적인 치유가 아닌 각각의 시스템의 상황을 인식하고 그것에 맞추어서 치유전략을 달리하는 상황인식 기능과 치유 결과 분석을 통해 치유전략을 자발적으로 개선해 나가는 기능을 제공한다. 구체적인 주요 기능은 다음과 같다: 치유대상들의 의존성 점검을 통한 근원적인 문제 해결, 자가치유를 위한 효율적인 리소스 사용, 벤더의 웹서버를 검색하여 치유정보를 수집, 벤더 의존성의 경감등, 치유프로세스의 개선은 물론 치유를 위한 관리자의 작업 부담을 상당 부분 경감할 수 있게 된다. 제안 시스템은 시뮬레이션을 통하여 그 유효성을 입증하고 있다.

• 한국심리학회지 : 문화 및 사회문제
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• 제10권spc호
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• pp.69-86
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• 2004

가정폭력은 아동기 경험에 의하여 폭력이 행동 레파토리로 학습된 남성이 사회적 존재로서의 자존감을 손상하는 경험을 반복적으로 하게 되는 경우에 나타나는 스트레스 반응이고, 결혼생활의 조화와 사회적 지지는 이 스트레스를 증폭하거나 완화시키는 완충역할을 한다는 견해가 설득력을 가진다. 가정폭력 사범의 교정을 위한 한국의 현행 제도는 교정과 치료가 교도행정기관에 의해 주도되므로 환자의 입장에서는 치료라기보다 대체형벌로 받아들일 가능성이 높아서 그 효과를 낙관하기 어렵고, 지역사회에서 낙인효과를 유발하여 재적응을 어렵게 만들며, 결과적으로 재범의 가능성을 높일 수 있다. 한국사회에서 가정폭력을 최소화하기 위한 법적 대처는 치료적 사법이념의 패러다임을 제도적 대처방안으로 섬세하게 고려할 필요가 있다. 치료적 사법이념의 핵심은 법원이 지역사회 및 다른 행정기관과 협력하여 범죄자의 치료와, 교정, 그리고 갱생을 위한 적극적이고 능동적인 역할을 해야 한다는 것이다.

• 한국환경보건학회지
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• 제36권3호
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• pp.236-246
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• 2010

In preparative anti-corrosive coating experiments, polyaniline was obtained by reacting an oxidizing agent with the monomer aniline. Further, the primer coating was prepared using a variety of widely-used materials such as urethane resin. For the top coating, epoxy resin and acrylic urethane resin were used. Characteristics of the coatings were assessed according to KS and ASTM specifications, and the structure of the polyaniline was characterized using FT-IR and TGA. For analysis of anti-corrosive properties in salt-spray experiments, measurements of the oxidation state of iron and surface atomic analysis were conducted using XPS and SEM-EDX. Unlike general anti-corrosive coatings which exhibit anti-corrosive effects only as a primer coating, the anti-corrosive coatings using polyaniline as the anti-corrosive pigment showed a marked synergistic effect with the top coatings. In other words, the top coatings not only produce a fine view effect, but also increase, through interaction with the primer coatings, the resistance to diffusion of corrosive factors from the external environment. It was also found that, unlike the heavy metal oxide-forming layer of the passive barrier alone, the polyaniline anti-corrosive pigment oxidized iron at the interface with the iron substrate to form a passive barrier in the oxidic layer, and itself formed a potential barrier layer with anti-corrosive factors from the external environment. Although the passive layer was damaged, the damaged area did not become completely oxidized iron; on the contrary, it showed a tendency to reduction. This can be interpreted such that a passive layer is formed again on the damaged area, and that at the same time there is a tendency to self-healing.

• Journal of Nutrition and Health
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• 제56권1호
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• pp.12-23
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• 2023

Purpose: This study investigates the alterations in A549 human non-small-cell lung cancer (NSCLC) cells exposed to Citrus junos extract (CJE). We further examine the antiproliferative and apoptotic effects of CJE on NSCLC cells. Methods: Inhibition of proliferation was examined by applying the 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) colorimetric assay on CJE-treated A549 NSCLC cells. The lactate dehydrogenase (LDH) assay was performed to measure the degree of toxicity of CJE on NSCLC cells. The effect on migratory proliferation was confirmed using the scratch wound healing assay. The antiproliferative effect of the CJE on human lung cancer cells was verified through morphological observation, fluorescence microscopy, and caspase-3 colorimetry. Results: Exposure of NSCLC cells to CJE resulted in a dose- and time-dependent decrease in cell activity and increased toxicity to the cells. In addition, microscopic observation revealed a reduced ability of the cancer cells to migrate and proliferate after exposure to the CJE, with simultaneous morphological apoptotic changes. Fluorescence staining and microscopic examination revealed that this death was a process of self-programmed cell death of NSCLC cells. Compared to unexposed NSCLC cells, the expression of caspase-3 was significantly increased in cells exposed to CJE. Conclusion: Exposure of A549 human NSCLC cells to CJE inhibits the proliferation, increases the cytotoxicity, and decreases the ability of cells to migrate and grow. Moreover, the expression of caspase-3 increases after CJE treatment, suggesting that the apoptosis of NSCLC cells is induced by a chain reaction initiated by caspase-3. These results indicate that Citrus junos is a potential therapeutic agent for human non-small-cell lung cancer.