• 한국지진공학회논문집
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• 제28권3호
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• pp.129-139
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• 2024

In this study, the SBC system, a new mechanical joint method, was developed to improve the constructability of precast concrete (PC) beam-column connections. The reliability of the finite element analysis model was verified through the comparison of experimental results and FEM analysis results. Recently, the intermediate moment frame, a seismic force resistance system, has served as a ramen structure that resists seismic force through beams and columns and has few load-bearing walls, so it is increasingly being applied to PC warehouses and PC factories with high loads and long spans. However, looking at the existing PC beam-column anchorage details, the wire, strand, and lower main bar are overlapped with the anchorage rebar at the end, so they do not satisfy the joint and anchorage requirements for reinforcing bars (KDS 41 17 00 9.3). Therefore, a mechanical joint method (SBC) was developed to meet the relevant standards and improve constructability. Tensile and bending experiments were conducted to examine structural performance, and a finite element analysis model was created. The load-displacement curve and failure pattern confirmed that both the experimental and analysis results were similar, and it was verified that a reliable finite element analysis model was built. In addition, bending tests showed that the larger the thickness of the bolt joint surface of the SBC, the better its structural performance. It was also determined that the system could improve energy dissipation ability and ductility through buckling and yielding occurring in the SBC.

• 시큐리티연구
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• 제24호
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• pp.91-123
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• 2010

G20 정상회의 시 발생 가능한 위협요인으로 요인테러, 인질테러, 폭탄테러, 다중이용시설 테러, 항공기테러 등 이 예상된다. 한국에서 예상되는 위협집단으로는 북한, 이슬람 과격집단 및 국제회의를 반대하는 NGO 조직 등의 단체가 위해를 일으킬 가능성이 있다고 본다. 이에 본 연구는 G20 정상회의가 주로 진행되는 장소인 주행사장과 숙소에서의 VIP 안전대책이 매우 중요하다고 판단하여 이에 대한 방안을 제시하는데 연구의 목적이 있다. 본 연구에서는 국내 최초로 경호원리 중 세계 각국에서 공통적으로 '3선경호원리'를 채택하고 있으므로 이 원리에 입각하여 1선(안전구역) 2선(경비구역) 3선(경계구역)별로 대응방안을 도출하고 VIP 안전대책을 위하여 정책적으로 반영하여야 할 의견도 함께 제시하였다. 결론적으로 G20 정상회의에 대비하여 주(主) 행사장에서의 VIP 안전대책을 위한 방안으로 1선(안전구역)에서는 첫째, 직가시 승하차지점에 대한 차단대책 강구해야 한다. 둘째, 노출지역에서는 과감하게 근접도보대형을 강화해야 한다. 2선(경비구역)에서는 첫째, 주 행사장의 특수성을 고려하여 출입통제대책을 강구해야 한다. 둘째, 행사비표 내에 RFID 기능이 포함된 효율적인 비표운용계획을 도입해야 한다. 3선(경계구역)에서는 첫째, 각종 요인테러대비, 정 첩보 수집 및 해외 정보기관과의 공조 하에 대테러 정보수집체계를 강화해야 한다. 둘째, 경호 행사인력에 대한 유사시 비상대책훈련을 실시해야 한다. 셋째, VIP 제대의 일정한 속도를 유지하기 위하여 효율적인 교통통제시스템을 운용해야 한다. 마지막으로 VIP 안전대책을 위해 정책적으로 반영하여야 할 점은 첫째, VIP 숙소의 효율적인 분산배치 및 통제가 이루어져야 한다. 둘째, 다양한 기만작전을 활용하여 불순분자가 오판하여 공격이 실패하도록 하여야 한다. 셋째, 북한 대남공작 기구의 개편에 따라 금번 G20 정상회의부터는 강력한 '군사지원대책'을 추진해야 한다. 이를 위해 국방부 주관 하에 전 후방 군사대비태세를 보다 강화하고, 화생방테러에 대비하여 탐지 및 제독에도 적극 적으로 대응할 것을 제안하고자 한다.

• 한국농공학회지
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• 제20권2호
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• pp.4645-4687
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• 1978

This study was attempted to investigate the mechanical properties of concrete and crack control effects of reinforced concrete with steel and glass fiber. The experimental program includes tests on the properties of fresh concrete containing fibers, compressive strength, tensile strength, flexural strength, Young's modulus, Shrinkage and deformation of steel or glass fiber reinforced concrete. Also this study was carried out to investigate the effect of steel or glass fiber to retard the development in reinforced concrete subject to uniaxial tension and thus facilitate the use of steels of higher strength. The major conclusions that can be drawn from the studies are as follows: 1. The effect of the fibers in various mixes on fresh concrete confirmed that fibers do have a significant effect on the properties of fresh concrete, bringing much more stable and exhibiting a signiflcant reduction in surface bleeding, and that the cohesion is greatly improved and the internal resistance increases with fiber concentration. But the addition of an excess contents and length of fibers brings about the reduction of workability. 2. With the addition of steel fibers(1.5% Vol.) to concrete, the compressive strength as compared with plain concrete showed a very slight increase, but excess addition, over 1.5% Vol. of steel and glass fiber reduced its strength. 3. Splitting tensile strength of fiber reinforced concrete showed a significant increase tendency, as compared with plain concrete. In case of containing steel fiber (2.5%, 30mm), it showed that the maximum increase rate of 1.48 times as much rate, and in case of containing glass fiber (2.5%, 30mm), the increase rate of strength was 1.25 times as much rate. 4. Flexural strength of fiber reinforced concrete showed a significant tendency, as compared with plain concrete. Containing steel fiber (2.5%, 30mm) showed the maximum increase rate of 1.64 times as much rate and containing glass fiber (2.5%, 30mm) showed the increase rate of strength of 1.32 times as much rate, and in general, the 30mm length brougth the best results. 5. The strength ratio ($\sigma$b/$\sigma$c and $\sigma$t/$\sigma$c) increased, when steel fiber's average spacing was up to 3.05mm, but decreased when beyond 3.05mm, and it was confirmed that tensile or flexural strengths of steel fiber reinforced concrete are apparently governed by fiber's average spacing. 6. The compressive strain of fiber reinforced concrete showed a significant increasing tendency as the fiber was added, but Young's modulus. with the addition of steel and glass fibers, showed a slight decrease tendency. And according to the increase of flexural strength, a considerable increase was seen in toughness. 7. With the addition of fiber's the shrinkage of concrete was significantly decreased, in both case of adding steel fibers 12.5%, 30mm, and showed a significant decrease ratio, in average 30.4% and 36.7%, as compared with plain concrete. 8. With the increase of fiber volume fraction and length, the gained stress in reinforcing bar in concrete specimens increased in all crack widths, but at different rates, with the decrease of fiber diameter, the stress showed a considerable increasing tendency. And the duoform steel fibers showed the greatest improvement, as compared with the other types tested. 9. The influence of fiber dimensions in order of significanse on the machanical properties of concrete and the crack control of reinforced concrete was explained as follows: content, length, aspect ratio and dimeter.

• 동의생리병리학회지
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• 제17권5호
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• pp.1157-1176
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• 2003

The following conclusions are induced from a study on the acupuncture therapy depending on hyungsang of the persons. The study is made on the basis of 'Internal classic (內經)& and &Clinical Lectures by Dr. Jeesan&. The acupuncture originated from the treatment of spasm with numbness in the southern area. The acupuncture is basically a remedy for the exterior disease of meridian but also it can be a cure for the interior disease of Jang and obstinate disease with accurate method. Three mechanisms of acupuncture are described in 'Internal classic'. The first is to make meridian circulate smoothly. The second is to regulate Ki and Hyul. The third is to regulate points through which the meridian-Ki goes in and out smoothly or adversely. There are two ways of acupuncture in 'Internal classic'. One is based on pulse and symptom and the other on the Hyungsang. The former is more generally used therapy, to which depletion method, Asi point method(阿是穴 療法), Inyoung-kigu pulse comparison method (人迎氣口脈法) and method depending on jang-bu disease belong. Acupuncture is done on Su points(輸穴) and back-su point(背兪穴) in case of jang-disease. In case of bu-disease, the treatment is done on Hap points(合穴) and Mo-points(募穴). The latter includes two methods; one according to invariable Hyungsang. And the other to variable Hyungsang. The method of acupuncture according to invariable Hyungsang usually selects Won-points(原穴). Different Hyungsang requires different method of acupuncture; In case of Dam type, the acupuncture is mainly practiced on four-Kwan points with reinforcing and reducing methods achieved by the direction of the needle tip pointing to. In case of Bangkwang type, the acupuncture is usually done on Jungwan(中脘) and Poongyung(豊隆) with reinforcing and reducing methods by means of respiration. In case of female, more effective are the acupoints on the right and lateral parts of the body selected on the basis of five su-points of the twelve meridians matching the heavenly stems and earthly branches. In case of male, more effective are the acupoints on the left, front and rear parts of the eight extra meridians. In case of acupuncture to the person with Hyungsang of five jang and six bu, each person's intrinsic Hyung, color, pulse, must be observed. Because symptoms of jang-bu disease also must be checked up. Acupuncture is done on the Won-points of the meridians related to the jang and bu where the disease starts. The disease of five jang is so obstinate that it requires both of medication and acupuncture for a long time. In case of acupuncture to the person with Hyungsang of animal types, diagnosis is made on the basis of shape, temper, function and color. And the treatment is given on the Won-points of corresponding exterior and interior meridians. For the fish type, the acupuncture is done on the kidney meridian of foot-soyin and the urinary bladder of foot-taiyang. For the bird type, on the heart meridian of hand-soyin, the pericardium meridian of hand-gualyin, and the small intestine meridian of hand-taiyang For the deer type, on the liver meridian of foot-gualyin and the gallbladder meridian of foot-soyang. For the turtle type, on the lung meridian of hand-taiyin and the large intestine meridian of hand-yangmyung.

• 대한한의학회지
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• 제19권2호
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• pp.125-136
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• 1998

This study is on the etiological factors of the obesity, symptoms of a disease caused by the etiological factors and the method of medical treatment resulted from symptoms of a disease, it is based on Dong-Yi Bo Gam. The conclusion of this study is as follows. 1. The final metabolic of fat is depend on the defensive energy. The shape of fatty layer is changed by the point where the defensive energy is replenish or not. So 'Goin(暠人)' 'Bein(肥人)' and 'Yuckin(肉人)' is made a discriminated and there is defferent between 'Besudaeso(肥瘦大小)' and 'Herlqidaso(血氣多少)'. 2. Etiological factors of obesity is ; essential substance from cereals overcome the primodial energy, spleen and stomach are strong at once, spleen and stomach are weak at once, spleen is disturbed by evil energy, retention of phlegm and fluid, muscle is weak, blood is excess but energy (qi)is weak, hua-sid(華食) eating the sweat food very often, a rich fatty diet. 3. To investigate each syndrome as etiological factons, essential substance from cereals overcome primodial energy is divided into two case: one is the food increase itself because of the weakness of stomach energy (qi), the other is not to digest the food because liver overact spleen by seven emotion. The obesity because of strengthen of the spleen and stomach at once do not feel hungry very well and spleen and stomach do not damaged easily by overacting. The obesity because of weakness of spleen and stomach at once, and disturbace in spleen cause by evil energy, gain the weight even if they eat food a little. Also it is hard to move four limbs. Weakness of muscle is weakness of spleen and stomach. Weakness of muscle is caused by weakness of spleen and stomach. That is the case of faining the weight because of eating food with an empty stomach. The obsity caused by retention of fluid has intestine rumbling and gain the weight suddenly. 4. The method of medical treatment fallowing to the etiological factors: The food is inclined to increase itself caused by weakness of stomach energy, In case of the obseity caused by this phenomenon. We can use Decoction for Reinforcing Middle wanner and Replenishing Qi(補中益氣湯), five tastes il-going-san(左味異功散) and so on. The method of medical treatment on obsity caused by strengthen of spleen and stomach is not referred yet. But we must investigate about using peptic powder(平胃散), ji-chul-huan(枳朮丸) for strengthen of stomach qi (胃氣). If the obesity appear caused by weakness of spleen and stomach and disturbance in spleen as to evil energy, and in the same time stomach qi is weak, we can use li-gong san(異功散). If not only obesity but also indigestion, we can use Decoction for naurishing the stomach and promotion eating(養胃進食湯). If not only obesity but also weakness of spleen and stomach, we can use Decoction for Reinforcing Middle warmer and replenishing Qi(補中益氣湯). The energy being weak, we can use Decoction for six noble drugs(六君子湯). If the obesity appear because of retention of fluid, we can use sin-chul-huan(神朮丸). On the obesit, caused by excess of blood and weakness of qi(血管氣虛), there is not method of mectical treatment yet, but the method of medical treatment that we count of first important maybe to invigorate the spleen and the lung qi and to disperse and recitify the depressed liver energy(疏肝利氣). The method of medical treament about the obesity caused by a rich fatty diet is not mentioned yet, but it is important to improve the lifestyle of food and we think that invigorate the spleen, and the lung-qi(補疏肝氣) and disperse and recitify the depressed liver-energy (??肝利機) amy count of first important. 5.There is useful medicine for weight down for example Herb tea(茶), red bean, wax gourd, etc. 6.The etiological factors of the obesity that revive frequently is weakness of qi(氣虛), from 形成氣衰, deficiency of yang, hasty of qi, damp and so on. The symptoms and sign of a disease that revive frequently to the obesity is appoplexia(中風), leucorrhea, reddish and whitish turbid, feeling of fullness in the upper abdomen, diabetes and so on.

• 대한치과보철학회지
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• 제50권4호
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• pp.279-284
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• 2012

연구 목적: 광중합형 레진에 미리 함침시킨 유리섬유를 이용하여 상악 레진상 총의치를 강화시킨 경우, 강화 부위의 위치가 파절 강도와 의치 파절 시 미치는 효과를 알아보기 위함이다. 연구 재료 및 방법: 본 연구에서는 0.45 mm의 두께를 가지고 광중합형 레진에 미리 함침시킨 유리섬유(SES MESH, INNO Dental Co., Yeoncheon-gun, Korea)를 이용하여 상악 총의치를 강화하였고, 강화재료의 위치 및 유무에 따라 5개의 군(대조군, 의치상을 섬유 망사로 강화하지 않음; A군, 순측 치조정 중앙부 강화; B군, 순측 치조정 하방의 구개 추벽부위 강화; C 군, 구개 중앙부위 강화; D 군, 의치상 전체 강화)으로 나누었으며, 군당6개의 시편을 제작하였다. 파절강도를 Instron test machine (Instron Co., Canton, MA, USA)을 이용해 5.0 mm/min의 크로스헤드 속도를 부여하여 구하였으며, 하중은 20 mm의 지름을 가진 구형 하중체를 통해 의치 중심부에 전달되었다. 파절 강도 시험 후 나타난 의치의 파절 양상을 분석하였다. 파절강도를 일원배치분산분석을 통해 검정하였다(${\alpha}$=.05). 결과: 파절강도에 있어 각 군간 통계적으로 유의한 차이를 보이지 않았다(P>.05). 의치의 파절 양상을 분석한 결과 A군에서는 전후방파절과 후방파절의 양상을 주로 보였고, B군, C군 그리고 대조군에서는 정중국소파절이 주로 관찰되었으며 D군에서는 대부분 후방파절을 보였다. 결론: 파절 강도를 측정하여 분석한 결과 유리 섬유에 의한 강화 유무와 위치에 따른 차이를 보이지 않았다. 의치의 파절 양상을 분석한 결과 유리 섬유에 의한 강화를 통해 균열을 억제하는데 효과를 보인다고 판단된다.

• 헤리티지:역사와 과학
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• 제46권3호
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• pp.212-228
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• 2013

파손된 석조문화재를 재사용하기 위한 방법으로 금속보강재를 사용하게 되는데 현재까지 보강재에 대한 보존처리 지침 없이 처리자의 경험에 의해서 이루어지다 보니 여러 가지 문제점이 도출되고 있다. 따라서 2차적인 원부재의 훼손을 최소화하기 위한 금속봉의 구조적 보강방법과 거동 특성 등을 제안된 실험체를 통해 검증 받아 금속보강재 매입방법에 관한 설계기준을 마련하고자 하였다. 절단면에 에폭시수지 접합만 할 경우 원 모재 물성의 70% 정도밖에 회복되지 않아 30%에 대한 금속보강재의 구조적 보강이 필요하다. 금속봉은 석재 취성파괴 후 구조적 거동을 받는데 금속보강재비가 0.251% 이하로 설계되면 구조적 거동은 발생하지 않으며, 0.5% 이상이면 구조적 보강은 이루어지나 모재의 2차 훼손을 유발시킨다. 따라서 $1,500kgf/cm^2$ 강도를 갖는 석재의 적정 금속보강재비는 접착단면적의 0.283~0.377% 정도로 설계되어야 가역성 있는 파손과 보강재의 연성거동이 이루어진다. 또한 휨 하중에 대응되는 금속봉의 최대 응력을 기대하기 위해서는 보강재 간격을 멀리하는 것보다 가깝게 유지하는 것이 효율적이며, 특히 상부에 보강재를 매입하는 것은 구조적으로 아무런 도움이 되지 못하고 오히려 원부재의 손상만 유발한다. 따라서 보강재는 하부에 집중배치하고 일부 중앙부에 매입하여야 안정적인 인장재 역할을 하면서 하중응력을 받는다. 금속봉의 분산효과는 보강봉의 면적에 영향을 받을 뿐 지름과는 무관하였다. 하지만 큰 규모를 대상으로 할 때는 접착 단면을 고려하여 보강재 개수를 늘려주는 것이 하중응력에 안정적이다. 이때 적용되는 정착길이는 보강재의 직경에 따라 다음과 같은 식($l_d=a_tf_y/u{\Sigma}_0$)에 의거하여 설계한다. 또한 구조재로서 거동을 하기 위해서는 반드시 마디가 있는 전산형 보강봉을 사용하여야 한다.

• 한국엔터테인먼트산업학회논문지
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• 제13권7호
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• pp.307-319
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• 2019

본 연구는 오색리를 중심으로 오색삭도 설치 사전에 침체된 오색지구 활성화를 위한 레저·관광 콘텐츠를 개발하여 지역활성화를 모색할 수 있는 기초자료를 제공하는 하는 것이 목적이다. 이를 위한 연구의 주요내용은 레저·관광콘텐츠의 개발을 위한 오색지구 현황 및 여건분석, 오색지구 레저·관광콘텐츠 개발 방향, 정책제언 및 결론 등으로 구성하였다. 본 연구에서는 오색지구 레저·관광콘텐츠 개발 방향과 관련하여 다음과 같은 개발 방향을 제안하였다. 첫째, 지역주민참여 확대 및 역량강화이다. 이를 실천하는 방안으로 조직체계 구축 및 지원강화, 지역 주민 역량강화, 외부 인적자원 네트워크 구축을 제안하였다. 둘째, 콘텐츠 개발 가이드라인 설정을 제안하였다. 오색지역 내 사회·문화·관광자원을 최대한 활용하기 위해, "문화예술활용형 콘텐츠"와 레저를 즐기는 수요자 증가추세에 부응하여 오색지구 자연환경을 이용한 레저체험 콘텐츠를 발굴할 것을 제안하였다. 셋째, 콘텐츠의 유형화를 제안하였다. 이를 실천하는 방안으로 오색을 주제로 한 문화콘텐츠 개발을 추진할 것을 제안하였다. 또한 지역상가 및 공공건물을 활용한 문화·예술·공연·전시 등의 공간 확보, 그리고 "오색지구"를 상징하는 상징물 조성, 오색지구 역사·문화를 그림으로 엮을 수 있는 "그림책 마을 조성"등을 제안하였다. 이와 아울러 체험 콘텐츠 개발 방향으로 테라피로드 체험 코스 및 푸드테라피 프로그램 운영 등과 함께 친환경적인 "오색 숲 길"을 조성할 것을 제안하였다. 넷째, 마케팅 채널 확보를 제안하였다. 이를 실천하기 위해 양양군 홈페이지, 또는 가칭 '오색이 아름다운 오색리' 홈페이지 제작, 여행사를 통해 오색지구 내 레저·관광콘텐츠와 교통, 숙박, 먹거리 등이 복합된 상품을 구성할 것을 제안하였다. 특히 오색지구 내에서 특별한 이벤트 개최 시에는 기획상품을 판매하는 방안을 제안하였다. 이와 함께 콘텐츠 개발 및 운영의 단계별 추진을 제안하였으며, 특히 전문가 등의 현장방문과 함께 참가자들에 대한 만족도 조사 등을 통해 오색지구 브랜드 제고에 노력할 것을 제안하였다.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.645-650
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• 1998

The dual drug-loaded alginate beads simultaneously containing drug in inner and outer layers were prepared by dropping plain (single-layered) alginate beads into $CaCl_2$ solution. The release characteristics were evaluated in simulated gastric fluid for 2 h followed by intestinal fluids thereafter for 12 h. The surface morphology and cross section of dual drug-loaded alginate beads was also investigated using scanning electron microscope (SEM). The poorlv water-soluble ibuprofen was chosen as a model drug. The surface of single-layered and dual drug-loaded alginate beads showed very crude and roughness, showing aggregated particles, surface cracks and rough crystals. The thickness of dual drug-loaded alginate beads surrounded by outer layer was ranged from about 57 to 329mcm. The distinct chasm between inner and outer layers was also observed. In case of single-layered alginate bead, the drug was not released in gastric fluid but was largely released in intestinal fluid. However, the release rate decreased as the reinforcing $Eudragit^{\circledR}$ polymer contents increased. When the plasticizers were added into polymer, the release rate largely decreased. The release rate of dual drug-loaded alginate beads was stable in gastric fluid for 2 h but largely increased when switched in intestinal fluid. The drug linearly released for 4 h followed by another linear release thereafter, showing a distinct biphasic release characteristics. There was a difference in the release profiles between single-layered and dual drug-loaded alginate beads due to their structural shape. However, this biphasic release profiles were modified by varying formulation compositions of inner and outer layer of alginate beads. The release rate of dual drug-loaded alginate beads slightly decreased when the outer layer was reinforced with $Eudragit^{\circledR}$ RS1OO polymers. In case of dual drug-loaded alginate beads with polymer-reinforced outer layer only, the initial amount of druc released was low but the initial release rate (slope) was higher due to more swellable inner cores when compared to polymer-reinforced inner cores. The current dual drug-loaded alginate beads may be used to deliver the drugs in a time dependent manner.

• Corrosion Science and Technology
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• 제14권2호
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• pp.99-105
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• 2015

The structures of reinforced concrete have been extensively increased with rapid development of industrial society. Futhermore, these reinforced concretes are easy to expose to severe corrosive environments such as seawater, contaminated water, acid rain and seashore etc.. Thus, corrosion problem of steel bar embedded in concrete is very important in terms of safety and economical point of view. In this study, specimens having six different coating thickness (W/C:0.5) were prepared and immersed in flowing seawater for five years to evaluate the effect of coating thickness and immersion time on corrosion property. The polarization characteristics of these embedded steel bars were investigated using electrochemical methods such as corrosion potential, anodic polarization curve, and impedance. At the 20-day immersion, the corrosion potentials exhibited increasingly nobler values with coating thickness. However, after 5-yr. immersion their values were shifted in the negative direction, and the relationship between corrosion potential and coating thickness was not shown. Although 5-yr. immersion lowered corrosion potential, 5-yr. immersion did not increase corrosion rate. In addition, after 5-yr. immersion, the thinner cover thickness, corrosion current density was decreased with thinning coating thickness. It is due to the fact that ease incorporation of water, dissolved oxygen and chloride ion into a steel surface caused corrosion and hence, leaded to the formation of corrosion product. The corrosion product plays the role as a corrosion barrier and increases polarization resistance. The corrosion probability evaluated depending on corrosion potential may not be a good method for predicting corrosion probability. Hence, the parameters including cover thickness and passed aged years as well as corrosion potential is suggested to be considered for better assessment of corrosion probability of reinforced steel exposed to partially or fully in marine environment for long years.