• 제목/요약/키워드: FORM

검색결과 41,591건 처리시간 0.055초

리브라스 거푸집의 적용을 위한 실험적 연구 (An Experimental Study on the Application of Lib-lath Form)

  • 남정민;박무영;이영도;정상진
    • 한국건축시공학회지
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    • 제4권4호
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    • pp.103-108
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    • 2004
  • In order for concrete as a basic material constituting reinforced concrete structure to meet the required performance, it is necessary to satisfy various requirements in concrete construction. Among them, form work has significant effects not only on the process of molding fresh concrete but also on the quality and performance of hardened concrete. Recently, the decrease and aging of form workers is becoming a great problem in the construction industry and, as a result, it is required to rationalize form works and reduce labor costs for employing form workers. Because form construction methods decide the type of form according to required performance, it is necessary to develop various form construction methods and examine their performance. Thus the present study purposed to expand the scope of application of form construction methods and, for this purpose, investigated the basic characteristics of rib- lath form and presented a system form construction method.

현대 주거건축에 있어서 추상적 형태 표현 특성에 관한 연구 (A Study on the Characteristics of Abstractive Form Expression in Contemporary Housing Architectures)

  • 장훈익
    • 한국주거학회논문집
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    • 제15권6호
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    • pp.15-25
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    • 2004
  • This study examined how the characteristics of abstractive form among various contenporary housing architecture have been expressed. The conclusions were: First, abstractive characteristics and types related to from expression of contemporary housing architectures were minimal form and absolute form of geometrical abstraction, plastic form and atypical form of expressive abstraction and mechanical aesthetics of industrial abstraction. Second, the typological form expression characteristics in minimal expression related to geometrical abstraction were simplicity, purity, and the properties of matter, and the characteristics in absolute expression were overlapping, obliqueness and dispensability. On the other hand, plasticity and mobility of materials were distinctive in plastic form expression, and inclination, curve and asymmetry were distinctive in atypical expression. The distinctive nature of mechanical aesthetics related to industrial abstraction included transparency, simplicity and. the properties of matter Funhermore, the study aimed at the understanding of various from expressions showed up in contemporary housing architecture, revealing the aspects of abstractive form expression characteristics.

형상 파라메터와 평활화 스키닝을 이용한 선수 선형 곡면 모델링 (Surface Modeling of Forebody's Hull Form Using Form Parameters and Fair-Skinning)

  • 김현철;황보승면
    • 대한조선학회논문집
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    • 제45권6호
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    • pp.601-610
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    • 2008
  • This paper deals with a new geometrical surface modeling method of forebody's hull form which is fully defined by form parameters. The complex hull form in the forebody can be modeled by the combination of three parts: bare hull, bulbous bow and blending part which connects a bare hull and a bulbous bow. All these subdomain parts are characterized by each own form parameters and constructed with simple surface model. For this, we need only 2-dimensional hull form data and then the form parameters are calculated automatically from these data. Finally, the smooth hull form surfaces are generated by parametric design and fair-skinning. In the practical point of view, we show that this new method can be useful and efficient modeling tool by applying to the hull form surface modeling of Panamax container's forebody.

A STUDY ON THE RELATION BETWEEN CLOSED-FORM DESCRIPTION AND RECURSIVE-FORM REALIZATION OF ASAPTIVE CONTROL OF MANIPULATORS

  • Kubozono, Takeshi;Yamakita, Masaki;Furuta, Katsuhisa
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.1785-1789
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    • 1991
  • Recently, a number of papers on adaptive control scheme of manipulators are proposed. Slotine and Li[1] showed an adaptive control scheme for robot manipulator. The controller was described in closed form. And later Niemeyer and Slotine discussed about a computational implementation of the controller in recursive form[2]. Walker proposed another adaptive control scheme which can be implemented by a recursive-form controller[4]. Closed-form description is used for the analysis or design of adaptive control systems while recursive-form realization is used for implementation of the controller. The relation between the closed-form realization and the recursive-form one seems to be inadequately referred. Hence, it makes sense to consider the relation between the closed-form description and the recursive-form one. In this paper, first, we make a simple derivation of an closed-form dynamics description of a robot arm from its recursive-form description. And then we derive the closed-form realization of Walker's scheme applied to manipulators having no kinematic loop. We clarify the difference between the Walker's scheme and Slotine's and evaluate the convergence under the controllers.

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비탈형 영구거푸집의 현장 적용을 위한 실험적 연구 (An Experimental study on field application of Permanent form)

  • 정근호;김우재;이영도;정재영;정상진
    • 한국건축시공학회지
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    • 제1권1호
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    • pp.143-150
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    • 2001
  • Permanent-Form is one of system forms for reducing human labor, work costs, oscillation, noise, construction wastes and so on. Permanent-Form is made from precast method in facilities, and carried in construction site to assemble with no demolding. The biggest expense to produce permanent-Form is about manufacturing mold. This papers about structural efficiency evaluation, construction efficiency test. The result of this study is below. (1) In the compressive strength test of column. Fly ash specimen and polymer specimen's strength developed as each 8%, 14% to comparison with standard specimen. The reason of this result from form section area increase and form's reinforcing bar (2) The Degree of column crack in permanent form is lower than another one's The glass fiber's fiber reinforcement effect brings like this. (3) In the flexural load test of beam, the early crack load and maximum load of permanent form use specimen showed 20% higher than standard specimen's. (4) In field application experiment, an constructional error is satisfied with the allowable margin of error, $\pm$5mm (5) When the concrete is placed into the form inside, The transformation degree of permanent form is lower than plywood form's. (6) The concrete packing ability of permanent form is satisfactory. (7) The bonding strength of permanent form shows enough strength - 6kgf/$\textrm{cm}^2$.

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프레드니솔론의 용출에 미치는 결정형의 영향 (Effect of Crystal Form on Dissolution of Prednisolone)

  • 손영택;도의선
    • Journal of Pharmaceutical Investigation
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    • 제33권2호
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    • pp.99-103
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    • 2003
  • Four different crystal forms of prednisolone, two polymorphic forms and two pseudopolymorphic forms, were obtained by the recrystallization from different organic solvents under varying conditions. The isolated crystal forms were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray powder diffraction (XRD). Form 1 was the most stable form that had the highest melting point and melt at $250.1^{\circ}C$. Form 2 was a monohydrate and Form 3 was a methanol solvate. The endothermic peak of Form 4 was shown at $230.2^{\circ}C$. When stored at different relative humidity over the period of 3 months, all of the modifications did not undergo transformation. The dissolution patterns of these four modifications were also checked in distilled water at $37{\pm}0.5^{\circ}C$, for 120 minutes. The dissolution rate of Form 4 was highest and those of Form 3, Form 2, Form 1 followed. Form 2, Form 3 and Form 4 had higher dissolution rate than Form 1.

Crystal Form of Celecoxib: Preparation, Characterization and Dissolution

  • Jin, Mi-Ryung;Sohn, Young-Taek
    • 대한화학회지
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    • 제62권5호
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    • pp.352-357
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    • 2018
  • Celecoxib (4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide) is a cyclooxygenase-2 inhibitor used in the treatment of arthritis, acute pain, and dysmenorrhoea. Celecoxib is a Biopharmaceutics Classification System (BCS) class II compound whose oral bioavailability is highly limited owing to its poor aqueous solubility. Several polymorphs of celecoxib have been identified as Form I, Form II, and Form III with melting points of about $162.8^{\circ}C$, $161.5^{\circ}C$, and $160.8^{\circ}C$, respectively. Form IV was generated from the precipitated suspension in the presence of HPMC (Hydroxypropyl methylcellulose) and Polysorbate 80. A rapid rate of dissolution is useful because the rate of dissolution of a drug typically increases its bioavailability. The aim of this study was to investigate the possibility of production of new crystal form of celecoxib that has higher solubility than Form III. New crystal form of celecoxib (Form A) has been isolated by recrystallization and characterized by differential scanning calorimetry (DSC), thermogravimetric (TG) analysis and powder X-ray diffractometry (PXRD). Form A was dissolved faster than Form III. At 30 minutes, the dissolution of Form A was 97.3%, whereas the dissolution of Form III was 82.2% (p < 0.1). After storage of three months at $20^{\circ}C$, in 24% RH (Relative Humidity), the crystal form was not transformed.

SMART 보 거푸집 개발을 위한 요구조건 분석 (Requirement Analysis for Development of SMART Beam Form)

  • 김태구;임채연;김선국
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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    • pp.70-71
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    • 2014
  • The structural work is the main process of building construction which influence on the time, cost, safety and quality. The form work is one of the main process which has from 20 to 30 percentage of structural work. Especially the form work for beams is complex and need more manpower compared with form work for column or slab. When the existing forms such as plywood form, steel framed wooden form and aluminum form, is used for form work of beam, it would result in the cost overrun caused by needs of lots of manpower and resources. Therefore, the aim of this study is analysis of the requirement for development of SMART beam form. The result of this study shall be used for the development of SMART form work system.

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Crystal Forms of Ketorolac

  • Sohn, Young-Taek;Seo, Hyun-Ok
    • Archives of Pharmacal Research
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    • 제27권3호
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    • pp.357-360
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    • 2004
  • Four crystal forms of ketorolac have been obtained by recrystallization in organic solvents under variable conditions. Different ketorolac polymorphs and pseudo polymorph were characterized by X-ray powder diffraction crystallography (XRD), Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In the dissolution studies in water at $37{\pm}0.5^{\circ}C$ four crystal forms showed different patterns. The solubility of Form I were the highest. The solubility decreased in rank order: Form I> Form II > Form III > Form IV. Form land Form III were shown to have a good physical stability at room temperature for 60 days. However, Form II is converted to Form III and Form IV is converted to Form I after 60 days storage. Therefore, these observations indicate that crystalline polymorphism for ketorolac is readily inter-convertible and the relationship may have to taken into consideration in the formulation of the drug.