• 제목/요약/키워드: Excessive use

검색결과 990건 처리시간 0.024초

장기폭로시험과 촉진시험에 근거한 염화물 함유량에 따른 철근콘크리트의 내구특성 (Durability Characteristics of RC containing Different Chloride Contents based on Long Term Exposure Test and Accelerated Test)

  • 권성준;송하원;신수철;변근주
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.759-762
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    • 1999
  • The concrete structures possessing good structural integrity can face durability problems due to deteriorations of concrete structures under various environmental conditions. The durability problems weaken the structural integrity in the long run. Especially, the excessive use of sea sand causes serious reinforcement corrosion and carbonation in concrete structures. An accelerated test is often used to predict deterioration as a qualitative measure, but without long term exposure test results or understanding of the relationship between the accelerated test and the long term exposure test, the accelerated test result alone can not be used effectively as a quantitative measure. In this paper, a methodology is proposed to predict the long term deteriorations, based on the result of the short-term accelerated test, of concrete containing different contents of chloride ions. Then, the correlation between two results on the steel corrosion ratio and the carbonation depth is analyzed for concrete with different chloride contents.

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팽창줄눈의 이론적 산정 (Theoretical Evaluation on Spacings of Expansion Joint)

  • 이홍재;이차돈
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.455-458
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    • 1999
  • It has been known that buildings having inappropriate expansion joints in their spacings may be subject to exterior damages due to extensive cracks on the outer walls under service loads, and structural damages due to excessive moment induced by temperature changes at ultimate load conditions. Rather inconsistent code provisions are available regarding spacings of expansion joints from different foreign structural codes and even worse, no quantiative measure on spacings is given in our codes for building structures. In order to establish a rational measure on the spacing of expansion joints, theoretical approaches are taken in this study. The developed theoretical formula is, then, converted to design chart for structural designer's convenience in its use. The chart considers both service and ultimate load stages.

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전환장애의 치료와 관리 (Treatment and Management of Conversion Disorder)

  • 오덕원
    • 한국전문물리치료학회지
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    • 제4권2호
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    • pp.77-88
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    • 1997
  • Conversion disorder is a psychologically produced alteration or loss of physical functioning suggestive of a physical disorder. Conversion symptoms are often superimposed on organic disease and can be overlooked. Psychological techniques are central to the management include the following: avoiding confrontation with the patients; avoiding reinforcement or trivializing the symptoms; reviewing results of tests and exams and creating an expectation of recovery; educating the patient before a treatment is begun; evaluating the patient's emotional adjustment and considering it at a treatment; using caution in labeling the condition; considering referral for psychotherapy; establishing particularly a treatment plan and making a definite treatment program; adjusting patient' s environment; letting participate a family at appropriate time; developing a reinforcement program for a treatment of chronic symptoms; developing a home program for outpatients. Use behavior therapy reinforcement may be helpful with more chronic or resistant symptoms, especially when there is a history of vague or excessive somatic complaints or significant secondary gain.

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Novel oxygenation for lipopeptide production from Bacillus sp. GB16

  • Lee, Baek-Seok;Lee, Jae-Woo;Shin, Haw-Shook;Choi, Sung-Won;Choi, Ki-Hyun;Lee, Jae-Ho;Kim, Eun-Ki
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2003년도 생물공학의 동향(XII)
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    • pp.240-244
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    • 2003
  • A novel integrated method for increasing dissolved oxygen concentration in culture media has been developed. It involves adding hydrogen peroxide to the medium, which is then decomposed to oxygen and water by catalase and adding vegetable oil to the medium as antifoam agent and oxygen vector. A new apparatus for automated addition of hydrogen peroxide to the bioreactor to keep the dissolved oxygen concentration constant over the range $10-100%\;{\pm}\;5%$ was tested. A significant increase (over threefold) of cultivation time was obtained while the dissolved oxygen concentration remained stable ($30%\;{\pm}\;5%$). Therefore, use of corn oil mixed with Ca-stearate as oxygen vector and antifoam and hydrogen peroxide as oxygen source to control excessive foam that was generated by microorganism biosurfactant, GB16-BS produced at Bacillus sp. GB16 cultivation was appropriate for stable cultivation.

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아돌프 로스의 장식배제에 관한 연구 (A Study on the Adolf Loos's renunciation of ornament)

  • 유연숙
    • 한국실내디자인학회논문집
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    • 제13권3호
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    • pp.11-16
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    • 2004
  • Adolf Loos studied at the Dresden Institute of Technology. He lived in America from 1893 to 1896. On his return to Vienna, hi worked for a year with the architect, Carl Mayreder. From 1897, he wrote extensively on design and architectural matters. In 1908, his famous article "Ornament and Crime"(Ornament und Verbrechen) was published, in which he linked the use of excessive decoration to a debasement of society. For Adolf Loos, it was a question not of renunciation of every ornament, but of the liberation from superfluous ornament. Where ornament was pastes on only, without connection with the subject or the building, and where ornament was not honest with the hand put on, the ornament is supposed to be removed. Onto the place of the ornament the joy of the material and the shaping should step. That the opinion of Adolf Loss is not correctly understood Is due on the one hand to the concentration on the 'ornament and crime' too very much. On the other hand his extreme Position is supposed to be understood more as thinking-impulse, more as provocation.ovocation.

KFP 엔진 박팍 부품 드로잉 성형해석 (Numerical Analysis of Forming for KEP engine Sheet matal part)

  • 오성국;정완진;안홍;이영호
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1994년도 박판성형기술의 진보
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    • pp.163-172
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    • 1994
  • The Aerospace and automobile industries have need to avoid sheet-metal forming problem such as incorrect springback after forming and trimming process, excessive thinning/tearing, wrinking/perkering. It is common practice to use costly trial-and-error experimental methods to develop tooling and manufacturing process parameters. Experimentation should be complemented with computer simulation to reduce cost and leadtime in manufacturing and to influence the design of components. In this study, firstly we solved the springback problem after drawing and trimming process of KFP(F100-229) engine airsealing bearing support part(53H00) forming and studied on the effect of several process parameters on the gap between the formed blank and punch shape using the implicit F.E.M code(ABAQUS). Secondly by the three dimensional dynamic analysis using the explicit. F. E. M code (LS-DYNA3D), we studied on the effect of several process parameters which can be used for avoid tearing and wrinking during the drawing process.

섬유 혼합토의 공학적 특성 (Engineering Properties of Fiber Mixed Soil)

  • 장병욱;박영곤
    • 한국농공학회지
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    • 제44권1호
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    • pp.116-124
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    • 2002
  • Natural resources fur the construction materials such as good soil, sand, and coarse aggregates have been encountered to be short due to excessive use by human. Even though some soil has been found to be unsuitable for construction materials, soil with reinforcement can naturally be an answer to these alternatives. According to recently published papers on fiber mixed soil, fiber mixed with soil can improve shear strength, compressive strength and post-peak load strength retention. In this study, a series of tests were performed to clarify the characteristics of fiber mixed soil and to give basic data for design and construction and their engineering properties, that is, unconfined compressive strength, splitting tensile strength, shear strength, crack by drying, freeze-thaw, creep and Poisson\`s ratio, were investigated and analyzed. It has been shown that fiber mixed soil is one of good alternatives fur the civil and building construction materials.

MODEL DUST ENVELOPES FOR ASYMPTOTIC GIANT BRANCH STARS. I. OH/IR STARS

  • Suh, Kyung-Won
    • Journal of Astronomy and Space Sciences
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    • 제12권2호
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    • pp.157-167
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    • 1995
  • OH/IR stars are the most massive and youngest subclass in asymptotic giant branch stars which pass through sporadic superwind phases. We have modeled the dust envelopes around OH/IR stars with close attention to the evolution of the structure of the dust shells. We use various dust density distributions to take account the effect of the superwind due to the helium shell flash by adding a density increased region. Depending on the position and quality of the density increased region, the model results are different from the results with conventional density distribution. The new results fit the observations of some OH/IR stars better. Especially, the OH/IR stars with excessive 30-100$\mu$m emission can be better explained by the new results. The IR two-color diagrams comparing the results of the superwind models and IRAS observation of 95 OH/IR stars have been made. The new results can explain much wider regions on the IR two-color diagrams.

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In situ horizontal stress effect on plastic zone around circular underground openings excavated in elastic zones

  • Komurlu, Eren;Kesimal, Ayhan;Hasanpour, Rohala
    • Geomechanics and Engineering
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    • 제8권6호
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    • pp.783-799
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    • 2015
  • In this study, effect of horizontal in situ stress on failure mechanism around underground openings excavated in isotropic, elastic rock zones is investigated. For estimating the plastic zone occurrence, an induced stress influence area approach (Bray Equations) was modified to define critical stress ratio according to the Mohr-Coulomb failure criterion. Results obtained from modified calculations were compared with results of some other analytical solutions for plastic zone thickness estimation and the numerical modelling (finite difference method software, FLAC2D) study. Plastic zone and its geometry around tunnels were analyzed for different in situ stress conditions. The modified equations gave similar results with those obtained from the other approaches. However, safer results were calculated using the modified equations for high in situ stress conditions and excessive ratio of horizontal to vertical in situ stresses. As the outcome of this study, the modified equations are suggested to use for estimating the plastic zone occurrence and its thickness around the tunnels with circular cross-section.

토지피복도 변화에 따른 제주도 주요 상시하천의 유출변화 분석 (Analysis of impact of land cover change on runoff through several Streams in Jeju Island, Korea)

  • 양성기;정우열;한웅규
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2010년도 추계학술발표논문집 2부
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    • pp.1033-1036
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    • 2010
  • Since Jeju island has depended a water resource on the underground water because of a poor development of the surface flow, Jeju island is in need of the surface resource development to prevent the future shortage of the underground water due to excessive development and use of it. The study shows that the SWAT model(continuous rainfall-runoff model) is applied to estimate the outflow in the drainage watershed area, where it has been urbanized through the change of the land, such as a tourism development, cultivation, housing, and impervious layer road development. Near watershed area in Jeju island, weather and topographical SWAT input data were collected, and compared the outflow change of past and present.

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