• 제목/요약/키워드: Conventional form

검색결과 1,679건 처리시간 0.034초

Hull Form Development for an AFRAMAX Tanker with a Composite Stern Frameline Concept

  • Kim, Ho-chung;Lee, Chun-ju;Kim, Su-hyung
    • Selected Papers of The Society of Naval Architects of Korea
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    • 제1권1호
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    • pp.65-75
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    • 1993
  • Hull form development for an AFRAMAX tanker characterized by the form parameters of $C_B\simeq0.8$, $L/B\simeq5.5$, $B/T\simeq3.5$, han been carried out by the application of ‘Composite Stern Frameline Concept’. The viscous resistance of the new form was much smaller than that of the conventional form. Form factor of the new form was only 0.18 compared to 0.30 for the conventional hull form, Nevertheless the propulsive efficiency was slightly lower and thus the required propulsion power was smaller by 5~6% at both full load and ballast condition. In addition, it is confirmed that introduction of the form factor method such as ITTC’78 method is highly advisable because there is a great risk of the underperdicting full scale resistance of the hull form whose form the extrapolation of moel resistance to full scale is to be based on Froude method with the correlation allowances usually applied to conventional hull forms.

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Polymorphism of Clarithromycin

  • Sohn, Young-Taek;Rhee, Jae-Keol;Im, Weon-Bin
    • Archives of Pharmacal Research
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    • 제23권4호
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    • pp.381-384
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    • 2000
  • It is well recognized that physicochemical properties of drugs are affected by the type of polymorphic crystalline form of drugs. Clarithromycin is known to exist in at least three polymorphic crystalline forms. Since conventional means to obtain the most thermodynamically stable form (Form II) for the antibiotics is known to be associated with a low purity of the stable form, we developed a novel method to improve the purity of the crystalline form by a modification of the preparation process. The new method involved a simple recrystallization of clarithromycin in solvents having 5-12 carbon atoms (e.g., hexane and heptane) or ethers with 4-10 carbon atoms (e.g., isopropyl ether) and, thus, less likely to be associated with the problem in purity of resulting crystal. Differential scanning calorimetry and powder X-ray diffraction were used to compare the crystalline form of the resultant powder with Form IIcrystal prepared by the conventional method. The crystal prepared by the new method was identical to Form IIcrystal of the conventional method as evidenced by the lack of the exothermic peak near 11$0^{\circ}C$ in differential calorimetry scan, indicating that Form IIcrystal could be readily prepared by the new process. Therefore, these data indicated that the improvement in the purity of the Form IIcrystal for clarithromycin as well as a significant cost reduction is likely by the novel method.

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자동차용 피스톤의 성형기술과 기계적 성질의 개선에 관한 연구 (A Study on the Forming Technologies for a Motor Piston and Improvement of Mechanical Properties)

  • 김길준;박종옥;김영호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.842-845
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    • 2000
  • The purpose of this paper is to investigate the influences on mechanical properties of motor pistons manufactured by casting, conventional forging and powder forging, using the comparison of characteristics like microstructure, hardness, tensile strength, and elongation. To form conventional forging piston, the experiment of visioplasticity was performed. As the model material, plasticine was used. To form powder forging piston, the shape of piston was simplified as simple cup shape. Material properties like workability, density variation before and after forging, and strain loci of material during forging were investigated. Powder forging and conventional forging technologies were effective to gain dense microstructure. In powder forging, distribution of such dense microstructuer was uniform. For hardness, pistons from powder forging and conventional forging technologies were much better than that from casting. For tensile strength and elongation, powder forging and conventional forging technologies were also advantageous.

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누진렌즈 디자인에 따른 원거리 대비감도 비교분석 연구 (A Comparative Analysis Study on Distance Contrast Sensitivities According to Progressive Lens Design)

  • 신동민;김수현;정주현
    • 한국안광학회지
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    • 제18권3호
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    • pp.241-246
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    • 2013
  • 목적: 본 연구에서는 프리폼 누진렌즈와 일반 누진렌즈를 착용 하였을 때 원거리 대비감도에 미치는 영향을 비교 분석 하였다. 방법: 안질환이 없는 성인 20명을 대상으로 원거리 대비감도 검사를 실시하였고 5단계의 공간 주파수를 갖는 F.A.C.T.(Stereo Optical, USA)를 이용하였다. 우안, 좌안, 양안 순서로 프리폼 누진렌즈와 일반누진렌즈 대비감도를 측정하였다. 결과: 우안/좌안/양안 대비감도 검사 값이 A(1.5 cpd) 공간주파수에서는 일반 누진렌즈에 비교하여 프리폼 누진렌즈가 16%/17%/11%, B(3 cpd) 공간주파수에서는 11%/5%/5%, C(6 cpd) 공간주파수에서는 6%/6%/9%, D(12 cpd) 공간주파수에서는 19%/16%/13%, E(18 cpd) 공간주파수에서는 4%/3%/18% 높았다. 결론: 원거리 대비감도의 모든 공간주파수 영역에서 프리폼 누진렌즈가 일반 누진렌즈보다 측정값이 높게 측정되었다.

골조형 주차장의 Deck Plate 대체형 목제 시스템 거푸집 적용성 연구 (A Study on Application for Deck Plate Substitute Type Wood System Form of Frame Type Parking Lot)

  • 신용재;신운식;허재원;임남기
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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    • pp.123-126
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    • 2006
  • Existing Deck Plate for a one of system forms, there is various advantage and application actual results increasing rapidly. But design of deck is depending on engineering data collections or design data on deck manufacture ordinarily. When construct, is responsible for deflection occurrence, And Because confirmation of crack occurrence region is impossible, there is difficulty of repair, reinforcement about crack and water leakage. According to got following conclusion as result that economic performance, preservation administration and repair reinforcement develops easy using steel truss snap tie by wedge pin on coating plywood that is slab Panel Wood System Form method of construction there is Deck Plate's advantage. (1) In stab lower part is exposed disjointing in which a criminal is fastened to be interrogated after construction acceptance and repair, reinforcement of crack is possible (2) Construction cost curtailment effect of about 29.2% than conventional type and about 10% than deck plate (3) Construction period reduction of about 3 day than conventional type and about 0.3 day than deck plate (4) Labor curtailment effect more than about $29{\sim}50%$ from conventional type

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고전적 테러리즘과의 비교 분석을 통한 뉴 테러리즘 양상에 대한 연구 (A Study on the Patterns of New Terrorism through the Comparative Analysis with Conventional Terrorism)

  • 송재형
    • 안보군사학연구
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    • 통권1호
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    • pp.113-154
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    • 2003
  • We can feel the fear through the reports of outbreaking centers of terror. Also, we noticed through "the 9.11 terror" that there exists no safety zone from terrorism. However, we should question ourselves whether we are relaxing attention or ceasing anxiety too much in the perimeter, as in the peninsula of Korea. Through "the 9.11 terror", the vulnerability of the United State's homeland security has been exposed, giving a serious damage to the national pride. President Bush started the war against terror to strengthen global joints of anti-terrorism, identify terrorists and contribute to the global peace, adopting offensive realism including preemptive attack concept which means to remove the threat preemptively. In today's reality of international politics, where the inhuman, indiscriminate, and anti-civilizational international terror became greater, extending to the stage of war, the international societies' agony and focus lies on how to banish it. The 9.11 terrorism, which is a new form of terrorism, is being distinguished from conventional terrorism into new terrorism. New terrorism is a new form of terrorism meaning that you do not know the enemy, the goal does not exist and they conscientiously use the weapons of mass destruction. This paper is a work meant to help understanding new terrorism, the new form, by a comparative analysis with the conventional terrorism. Therefore the origin, concept and general characteristics new terrorism is picked out and the representative forms of it, which are suicide bombing, cyber, biochemical and nuclear terrorism, are analyzed in detail in theoretical manner.

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Hull form design for resistance minimization of small-scale LNG bunkering vessels using numerical simulation

  • Pak, Kyung-Ryeong;Song, Gi-Su;Kim, Hee-Jung;Son, Hye-Jong;Park, Hyoung-Gil
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제12권1호
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    • pp.856-867
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    • 2020
  • This paper aims to provide the most useful method of determining an optimum LCB position and design direction of fore- and aft-body hull shape for a SLBV. It is known that the SLBV has a lower length-to-beam ratio, larger Cb and simpler stern shape designed for the installation of azimuth thrusters comparing to those of conventional LNG carriers. Due to these specific particulars of SLBV, the optimum LCB position was very different to that of conventional LNG carrier. And various approaches were applied to determine the optimum fore- and aft-body hull shape. The design direction for the optimum hull-form was evaluated as the minimization of the total resistance which includes the wave-making resistance and form-drag with numerical simulation.

한글 간찰(簡札)의 상투적(常套的) 표현(表現) 고찰(考察) (A Study on Conventional Expression of Hangul Ganchal)

  • 전병용
    • 동양고전연구
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    • 제37호
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    • pp.279-306
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    • 2009
  • 본고의 목적은 한글 간찰을 대상으로 상투적인 표현을 고찰하는 데 있다. 한글 간찰의 상투적인 표현은 한글 간찰의 격식(格式)의 완성과 더불어 16세기에서 17세기에 이르는 과정에서 그 기틀이 마련되었다. 한글 간찰의 상투적 표현은 서두(書頭) 부분과 결말(結末) 부분에서 중점적으로 쓰였다. 서두에서는 호칭(呼稱)과 안부인사(安否人事)에서, 결말(結末)에서는 결말인사(結末人事)와 결귀(結句)에서 많이 쓰인 것을 알 수 있었다. 호칭 상투적 표현은 16세기의 <순천김씨언간>이나 17세기의 <현풍곽씨언간>에서는 서두의 자리에 고유어 중심의 상투적인 표현이 쓰였으며, 19세기의 <징보언간독>에서는 서두의 자리에 한자어 중심의 상투적 표현이 쓰였다는 점이 달랐다. 안부 인사의 상투적 표현에서는 답상(答狀)의 경우 '유무 보고' 같은 상투적 표현이 덧들어간다는 점에서 기상(寄狀)의 표현과 달랐다. 16세기의 <순언>에서 상투적 표현으로 점차 자리 잡아 가는 과정을 포착할 수 있었고, 17세기의 <현언>에서는 고유어 중심의 상투적인 표현이 하나의 정형(定型)을 이루게 된 것을 알 수 있었다. 다만 19세기의 <징언>에서는 <현언>의 고유어 중심의 상투적 표현이 오히려 한자어 중심의 상투적 표현으로 대체된다는 점이 특이하였다. 결말 인사와 결구 표현도 안부 인사 표현과 같은 양상을 보이고 있음을 알 수 있었다. <순언>보다 <현언>의 결말 인사와 결구 표현이 훨씬 단순화되어 반복적으로 쓰임으로써 상투성을 확보하는 것을 파악할 수 있었으며 아울러 <징언>에서는 오히려 한자어 중심의 번역체로 바뀌고 있음을 알 수 있었다.

간접 패턴을 이용하는 스마트폰 보안 키패드 설계 (Design of Smartphone Secure Keypad Using Indirect Pattern)

  • 최동민
    • 한국멀티미디어학회논문지
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    • 제25권7호
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    • pp.932-944
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    • 2022
  • Smartphones, are currently equipped with high-performance hardware to process large amounts of data and provide most of the functions provided by desktop PCs. In addition, the smartphones enable quick user authentication through biometric information collected from embedded sensors. However, the biometric authentication method is sometimes rejected due to social and cultural environment, security vulnerabilities, and misrecognition rate. Thus, conventional authentication methods such as PIN and pattern authentication are still mainly used. Consider the latest foldable and bendable smartphones. These devices may be vulnerable to social engineering attacks as they use conventional authentication methods without considering their form factors. In this study, therefore, we propose an authentication method using partial elements of PIN and pattern authentication as a way to increase the security of the conventional authentication methods and consider the recent form factors. According to the performance evaluation results, our method provides improved safety compared to the conventional methods.

미국 중소도시의 형태기반코드 구성요소에 관한 연구 - 건축계획요소를 포함한 조닝코드 사례를 중심으로 - (A Study of Components in Form-Based Codes of Small to Mid Cities in US - Focused on Zoning Codes Including Architectural Design Elements -)

  • 박성용;안동준
    • 대한건축학회논문집:계획계
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    • 제34권4호
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    • pp.77-85
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    • 2018
  • Rapid urbanization has fostered development of modern cities. Although Conventional zoning played its role to control urban development, it also segregated land uses and created homogeneous development pattern. Mega cities with satellite bed towns has not shown their unique identity and characters. In order to develop comprehensive approach which may bring social and physical enhancement can be difficult to achieve by considering city as a two dimensions. On contrary, extensive analysis and proposals require an approach which can perceive city with three dimensions. Form-Based Codes (FBCs) are appeared as an alternative to conventional zoning with different design process and principles. FBCs approach urban place with three dimension and giving priority to form rather than land use. The purpose of this study was to analyze the necessity of FBCs and its concept, components and how this would change urban characteristics in the aspects of architectural design through analysis on 4 case studies for zoning codes of US cities. Through comparison of components in Form-Based Codes of 4 different cases, this study can show the reasons for differences in application of Form-Based Codes and how detailed components would play a role to establish better urban environments.