• 제목/요약/키워드: Reinforcing

검색결과 3,015건 처리시간 0.028초

역경사형 토목섬유 보강토 구조물에 탄소성 모델의 적용 (An Application of Elasto-Plastic Model to Overhanging Geosynthetic-Reinforced Soil Structure)

  • 김은라;;김유성
    • 한국지반신소재학회논문집
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    • 제3권4호
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    • pp.3-12
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    • 2004
  • 본 연구는 토목섬유 보강토 구조물의 보강 메카니즘을 규명하고자 하는 목적으로 실시하였으며, 여기서 보강 메카니즘은 전단에 의한 다짐토의 체적 팽창(부의 다일러턴시)을 토목섬유에 의해 구속 억제하는 과정에서 생성되는 효과로 간주하고 있다. 실물 현장시험은 일본 Kanazawa(1994)에서 실시했으며, 실내시험으로는 등체적 전단시험을 실시하여 강도 및 변형특성을 조사하였고, 시험결과를 이용하여 유한요소해석에 필요한 재료 파라메타를 결정하였다. 또한, 탄소성 유한요소 해석을 실시하여 이론치와 실험 결과치를 정량적으로 비교 분석되었으며, 그 결과 유한요소 해석이 현장 시험을 유용하게 설명할 수 있는 것을 알 수 있었다.

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골재의 종류에 따른 포러스콘크리트의 특성에 관한 실험적 연구 (An Experimental Study on the Characteristic of Porous Concrete using different Aggregates)

  • 정시진
    • 한국건축시공학회지
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    • 제4권1호
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    • pp.89-96
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    • 2004
  • Porous concrete is used of various parts by advantage of porous. Example of growing of plant is possible, and dwelling of creature, and filter functions of various contaminant, and decrease of noise, and so on. This research is for porous concretes that were used by four aggregate rubble, refreshing aggregate, expanded clay, orchid stone. This research estimate that physical and mechanical characteristics of fresh concrete and hardened concrete. The purpose of this research is to make environment-friendly porous concrete. This research's conclusion is as following : 1. Porous Concrete's slump was measured 12~14cm with rubble, 12~16cm with refreshing aggregate, 11~13cm with expanded clay, 11~13cm with orchid stone. Weight of aggregate was bigger, slump price appeared by bigger thing. Because placed Porous Concrete is low viscosity and small resistance between aggregate, it estimated that have high workability. 2. Porous Concrete's unit weight was measured 1.71~1.75t/$\textrm{m}^3$ with rubble, 1.58~1.62t/$\textrm{m}^3$ with refreshing aggregate, 1.19~1.20t/$\textrm{m}^3$ with expanded clay, 0.98~1.06t/$\textrm{m}^3$ with orchid stone. Showed aspect such as weight of aggregate. 3. Porous Concrete's compressive strength was measured 76~102kgf/$\textrm{cm}^2$ with rubble, 51~60kgf/$\textrm{cm}^2$ with refreshing aggregate, 30~40kgf/$\textrm{cm}^2$ with expanded clay, 13~16kgf/$\textrm{cm}^2$ with orchid stone. 4. Tendency of tensile strength and bending strength showed generally similarly with compressive strength, but showed low value fewer than 15kgf/$\textrm{cm}^2$ Therefore, wire mesh, reinforcing rod, such as establishment of frame is considered to need in reinforcement about tensility or flexures in case receive tensility or produce product of thin absence form. It concludes by speculating on the consequences of extrapolating the results of study to remodelling the office building being already existence.

삽입된 광강도형 광섬유센서가 지능형 복합재 구조물의 건전성에 미치는 영향 및 피로손상 감시 (Effect on the structural integrity and fatigue damage monitoring of smart composite structures with embedded intensity based optical fiber sensors)

  • 이동춘;이정주;서대철;허증수
    • 센서학회지
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    • 제10권1호
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    • pp.42-51
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    • 2001
  • 본 연구에서는 복합재료에 삽입된 광섬유센서의 인장하중하에서의 정적 물성치와 피로하중하에서의 동적 물성치를 실험적인 방법과 유한요소해석을 통하여 고찰하였다. 결과에 의하면 삽입된 광섬유센서는 인접한 강화섬유에 수직한 방향으로 삽입된 피로하중의 경우를 제외하고 복합재료의 기계적인 물성치에 큰 영향을 끼치지 않는다고 결론지을 수 있다. 광강도형 광섬유센서를 복합재료 적층판에 삽입하여 복합재 적층판의 강성저하를 측정함으로써 직교적층판 피로손상을 검출하였다. 이 실험의 결과에 의하면 광강도형 광섬유센서는 간단하고 저렴한 장치와 측정된 신호의 복잡한 후처리 과정이 필요 없다는 장점으로 인하여 구조물의 강성저하를 측정하여 피로손상을 감시하는데 있어서 큰 잠재력을 가진다고 할 수 있다. 또한 삽입된 광강도형 광섬유센서는 우수한 내 피로성과 넓은 강성측정 범위를 보였다.

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최근린사상법을 활용한 6대 광역시 녹지네트워크 경향 분석 (An Analysis of Urban Green Network using Nearest Features Model in Korean Metropolitan Cities)

  • 오정학;장갑수;김용범
    • 한국환경복원기술학회지
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    • 제13권5호
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    • pp.135-145
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    • 2010
  • This study was carried out to investigate the current urban forest network and future plan of forest framework using nearest features program where stepping stones within 5km from the core forest were selected in the program. We found several conclusions as follows: First, we found that cities in inland area including Daegu, Dajeon and Gwangju have quite different types of forest network with comparing to the cities nearby coastline including Busan, Incheon and Ulsan. The cities in inland area have large mountain patch around each city. However they have small and lower number of island forests within their urban area. Otherwise, cities nearby coastline have more forest patches than in the cities in inland area, and Busan and Incheon especially have strong forest network using various size of forest patches. Second, Daegu and Daejeon have much smaller forest patches distributed in each urban area. So additional forest patches should be added to have highly strong forest network within urban area. Third, Ulsan and Gwangju have most stepping-stone forests close to the large mountain patches in suburban area, which are not able to connect to the forest patches in the central area of each city So additional forest patches are needed to be added in the central area of each city for reinforcing the effect of stepping stone in the central area. Though there should be an addition approach except for forest size and its isolation to construct the ecological network in an urban area, this indices can be a good method to check an environmental and ecological status in an urban area.

일본의 고령화에 따른 의료서비스 대책 (Medical Service Countermeasures Following Aging in Japan)

  • 최성백
    • 감성과학
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    • 제19권2호
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    • pp.79-88
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    • 2016
  • 현대사회는 산업혁명 이후 물질적 풍요로움 속에 살고 있다. 한편 제품에 다양화에 따른 소비자들의 욕구도 다양화 되고 있다. 현대 소비자들은 과거와 달리 단순히 목적 지향적인 소비가 아니라 감성과 가치관을 충족시키는 개성적 소비로 트렌드가 바뀌고 있다. 그 대표적인 사례가 스타벅스다. 스타벅스는 매장 장식부터 시작해 전 세계 어느 매장이든 똑같은 자신들만의 매장 음악, 직원들의 서비스, 매력적인 커피 향 등으로 구성된 스타벅스만의 분위기를 파는 감성마케팅으로 오늘날 세계적인 커피 프랜차이즈로 성장했다. 이런 방법은 인간의 감성을 자극 하는 마케팅이기 때문에 눈에 보이지 않는 것을 인간의 감각이나 감성에 대입하여 호소하는 방식이다. 즉, 소비자들의 감성을 끌어 내어 제품에 대한 긍정적인 반응을 이끌어 내어 소비까지 이루어지게 하는 것이 감성마케팅의 매력이다. 제품이나 서비스에서 감성의 활용은 브랜드 이미지를 차별화하고 브랜드 로열티를 강화할 수 있는 핵심적인 방법이 되고 있다. 특히 소비자의 감동을 강하게 이끌어 내기 위해 고객서비스가 더욱 중요시 되고 있다. 무형의 서비스는 고객의 감동을 이끌어내는 최고의 수단이 되고 있다.

Wild Ginseng Attenuates Repeated Morphine-Induced Behavioral Sensitization in Rats

  • Lee, Bom-Bi;Kwon, Sun-Oh;Yeom, Mi-Jung;Shim, In-Sop;Lee, Hye-Jung;Hahm, Dae-Hyun
    • Journal of Microbiology and Biotechnology
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    • 제21권7호
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    • pp.757-765
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    • 2011
  • Many studies have suggested that the behavioral and reinforcing effects of morphine are induced by hyperactivation of the mesolimbic dopaminergic system, which results in increases in locomotor activity, c-Fos expression in the nucleus accumbens (NAc), and tyrosine hydroxylase (TH) in the ventral tegmental area (VTA). In order to investigate the effect of wild ginseng (WG) on treating morphine addiction, we examined the behavioral sensitization of locomotor activity and c-Fos and TH expression in the rat brain using immunohistochemistry. Intraperitioneal injection of WG (100 and 200 mg/kg), 30 min before administration of a daily injection of morphine (40 mg/kg, s.c.), significantly inhibited morphine-induced increases in c-Fos expression in NAc and TH expression in VTA as well as in locomotor activity, as compared with Panax ginseng. It was demonstrated that the inhibitory effect of WG on the behavioral sensitization after repeated exposure to morphine was closely associated with the reduction of dopamine biosynthesis and postsynaptic neuronal activity. It suggests that WG extract may be effective for inhibiting the behavioral effects of morphine by possibly modulating the central dopaminergic system and that WG might be a useful resource to develop an agent for preventing and treating morphine addiction.

폴리케톤 섬유의 염색 및 후가공 처리에 따른 기계적 물성에 관한 연구 (Study on the Mechanical Properties of Polyketone Fiber according to Dyeing and Finishing Process)

  • 김상룡;김경민;이원;이득진;황순동;양성용
    • 한국염색가공학회지
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    • 제29권2호
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    • pp.97-103
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    • 2017
  • Polyketone fiber, a newly developed high strength fiber, has a tenacity and modulus similar to the p-aramid fiber, and can be used for reinforcing mechanical rubber goods(MRG), such as tires, hoses, and technical textiles. It will be expected for replacement of super fiber such as aramids and increasing the technical textile market share. This paper surveys the mechanical properties of polyketone fiber for technical textiles. For this purpose, dyed polyketone fabric is prepared, mechanical properties of coated and uncoated polyketone fabrics such as tensile strength, elongation and tear strength were examined before and after weather resistance test(temperature $63{\pm}3^{\circ}C$, humidity 60%, amount of power $0.35w/m^2$). The differences of mechanical properties between uncoated and coated fabrics for high functional technical textiles and composite materials are estimated through this study. The UV-stability of polyketone fabric showed obvious improvement after coating. After 168h(7day) of UV exposure, the coated fabric showed less deterioration in mechanical properties with the retained tensile strength and elongation at break greater than 22 and 17% of the uncoated polyketone fabrics values, respectively.

치위생(학)과 학생들의 임상실습과 전공만족도가 진로준비행동에 미치는 영향 (Effects of clinical practice and major satisfaction of dental hygiene students on career preparation behavior)

  • 김수경;강리우;김은용;문정은;장지희;정은서
    • 한국치위생학회지
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    • 제18권2호
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    • pp.239-251
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    • 2018
  • Objectives: The purpose of this study was to investigate the effects of dental hygiene students' clinical practice stress, satisfaction and major satisfaction on career preparation behaviors. Methods:This study was conducted targeting the dental hygiene students who have clinical practice experience. The final 305 subjects were analyzed using SPSS 22.0 program. Results: The correlation between clinical practice stress and career satisfaction and career preparation behavior decreases with the higher degree of clinical practice and career preparation behavior. Analysis results about the affecting factors on the level of satisfaction with major satisfaction factors showed the highest factor of preparation behavior, followed by clinical practice and clinical practice stress in order. Analysis results about the affecting factors on the showed the highest factor of preparation behavior, followed by clinical practice and clinical practice stress in order. Conclusions: The results of this study showed that the higher the satisfaction of clinical practice and the higher the satisfaction of career, the more positive the career preparation behavior. Therefore, it's recommended to support continuous education programs to be coherent with dental hygiene student's career preparation behavior based on reinforcing individual competency by obtaining self-confidence and satisfaction from clinical practice.

증기양생이 고로슬래그 콘크리트의 압축강도에 미치는 영향 (Effect of Steam Curing on Compressive Strength of Slag Binder Concrete)

  • 임병훈
    • 한국산학기술학회논문지
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    • 제18권8호
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    • pp.338-343
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    • 2017
  • 본 논문은 이산화탄소 배출저감 및 산업폐기물을 재활용하기 위한 일환으로 산업부산물인 고로슬래그 미분말을 사용하였다. 고로슬래그 미분말은 선철의 제련 시 부산물로서 발생하는 고온 용융상태의 고로슬래그를 물로 급냉 시켜 유리화한 것으로 반응성이 높아 시멘트 및 콘크리트용 혼화재료로 다양하게 사용되고 있다. 고로슬래그 미분말을 치환한 콘크리트는 수화발열속도 저감, 온도상승 억제, 장기강도 향상, 수밀성 증대에 의한 내구성 향상 및 염화물 이온 침투억제에 의한 철근의 발청 억제 등의 다양한 효과를 기대할 수 있다. 그러나, 재령 초기 낮은 압축강도로 인해 사용량이 적은 실정이다. 따라서, 본 연구에서는 고로슬래그 미분말을 치환할 경우 낮은 압축강도를 보완하기 위해 증기양생이 초기 강도 발현에 미치는 영향을 평가하였고, 압축강도, SEM, EDS, XRD와의 관계를 분석하여 콘크리트의 압축강도 발현특성을 검토하였다. 그 결과 고로슬래그 미분말을 30% 치환한 콘크리트가 가장 우수하였으며, 이는 증기양생에 의해 고로슬래그 미분말의 피막을 파괴하여 ettringite 및 C-S-H겔 등의 수화물을 생성함으로 압축강도에 영향을 마친 것으로 판단된다.

Determining attitudinal and behavioral factors concerning milk and dairy intake and their association with calcium intake in college students

  • Rose, Angela M.;Williams, Rachel A.;Rengers, Brooke;Kennel, Julie A.;Gunther, Carolyn
    • Nutrition Research and Practice
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    • 제12권2호
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    • pp.143-148
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    • 2018
  • BACKGROUND/OBJECTIVES: Average intake of calcium among college students is below the recommended intake, and knowledge surrounding the attitudinal and behavioral factors that influence milk and dairy intake, a primary food source of calcium, is limited. The purpose of this study was to evaluate college students' attitudes and behaviors concerning milk and dairy consumption and their association with calcium intake. SUBJECTS/METHODS: Participants were 1,730 undergraduate students who completed an online survey (SurveyMonkey) as part of baseline data collection for a social marketing dairy campaign. The online survey assessed attitudes and behaviors concerning milk and dairy intake, and calcium intake. Questions about milk- and dairy-related attitudes and behaviors were grouped into 14 factors using factor analysis. Predictors of calcium intake were then evaluated. RESULTS: Median calcium intake across all participants was 928.6 mg/day, with males consuming higher calcium intakes than females (P < 0.001). Adjusted for gender, calcium intakes were most strongly (and positively) correlated with associating milk with specific eating occasions and availability (i.e., storing calcium-rich foods in one's dorm or apartment) (both P < 0.001). Other correlates of calcium intake included: positive-viewing milk as healthy (P = 0.039), having family members who drink milk) (P = 0.039), and taking calcium supplements (P = 0.056); and negative-parent rules concerning milk (P = 0.031) and viewing milk in dining halls negatively (P = 0.05). CONCLUSIONS: Calcium intakes among college students enrolled in the current study was below the recommended dietary allowance of 1,000 mg/day, reinforcing the need for dietary interventions in this target population, especially females. Practitioners and researchers should consider the factors found here to impact calcium intake, particularly associating milk with specific eating occasions (e.g., milk with breakfast) and having calcium-rich foods available in the dorm room or apartment, as intervention strategies in future efforts aimed at promoting milk and dairy foods and beverages for improved calcium intake in college students.