• Title/Summary/Keyword: 간접-직접법

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나노트라이볼로지를 이용한 박막 및 표면의 물성 분석

  • Lee, Chang-U
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.4-4
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    • 2010
  • 박막의 물성을 분석하는 방법에는 광학을 이용한 분광학 분석법과 나노크기의 tip을 이용한 나노트라이볼로지 분석법이 대표적이라 할 수 있다. 분광학 분석법에는 주로 X-ray 회절분석, Raman 분광기, IR 분광기 등등이 가장 대표적으로 사용되어지는 분석 장치들이다. 이러한 분광학 분석은 광학을 시료에 조사하여 이로부터 획득되는 강도(intensity)를 분석하는 방법으로 간접적인 분석이라 할 수 있다. 이에 반하여 나노트라이볼로지는 나노크기의 tip을 이용하여 시료 표면을 직접적인 방법으로 분석하여 시료의 형상, 탄성, 강도, 마찰력 등의 정보를 제공하며, tip에의 전기적 신호를 부과하여 시료 표면의 국부적인 potential, electric current를 측정하게 된다. 이에 해당되는 대표적인 분석 장치로는 nano-indenter system과 SPM (Scanning Probe Microscopy)이 있다. 따라서, 이 논문에서는 나노트라이볼로지의 대표적인 장치인 nano-indenter system과 SPM에 대한 간단한 원리를 소개하고 다양한 분야에 대한 실제적인 분석을 사례를 통하여 나노트라이볼로지의 가치를 확인하고자 한다.

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A Study on the Harris's Thought and Classification Scheme (해리스의 사상과 분류법에 관한 연구)

  • Kim, Jeong-Hyen
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.21 no.2
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    • pp.69-80
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    • 2010
  • This study analyzed the Harris's philosophical ideas, American library classification in the Harris's era, and relationship to Bacon, Hegel, DDC based on the Harris's classification system. As is generally known so far, Harris himself described to have derived his classification from inverted Baconian arrangement. It is nowhere to be found that Harris reflected on Hegel's philosophical ideas in his scheme. But on this study, Harris was a Hegelian and a leading American exponent of ideas of Hegel at that time. So we can analogize being reflected on Hegelian philosophy in the Harris's scheme and actually the Hegelian basis can be founded for much of Harris's scheme. Also we can find that Harris's scheme springs directly from Bacon and indirectly Johnston's scheme.

피로균열진전거동 평가를 위한 균열길이 측정법 - 직류전위차법

  • 한승호
    • Journal of the KSME
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    • v.37 no.10
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    • pp.41-46
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    • 1997
  • 철강구조물 부재 내에 노치나 균열이 존재할 수 있고, 외부의 피로하중에 의하여 취약부에서 발생한 균열이 진전하여 전구조물의 최종파손을 야기시킬 수 있다. 부재를 보다 안전하게 사용하고 또한 신뢰성을 확보하기 위해서는 이미 손상된 부재에서 균열의 진전상태를 계측할 수 있는 방법이 확립되어져야 하고, 파괴역학적 파라미터를 이용한 사용재의 균열진전거동특성이 평가되어야 한다. 균열길이의 측정방법은 지금까지 많은 연구자들에 의하여 개발되어져 왔는데 크게 광학현미경을 이용하여 육안으로 직접 균열길이를 측정하는 방법과 컴플라이언스, 초음파, AE 또는 전기적 신호를 통하여 얻어진 결괄부터 균열길이로 환산하는 간접적인 방법으로 대별된다. 대부분의 균열길이의 측정방법은 많은 수작업이 요구되고, 특히 하한계응력확대계수영역의 미세한 균열진전량을 측정하기에는 어려움이 따르고 있다. 이에 대하여 전도체 시험편에 일정전류를 흐르게 하고 균열길이의 증가에 따라 변화하는 전위차로 이를 균열길이로 평가하는 전기적인 측정방법이 있다. 이 방법은 실험장치가 비교적 간단하고 미세한 균열길이의 측정이 용이하여 균열길이의 직접적인 측정이 곤란한 고온역 그리고 충격하중하에서의 균열길이 측정에 이용이 확대되고 있다. 이 글에서는 여러 균열길이 측정방법의 장.단점에 대하여 고찰하고, 그 중 많은 장점을 갖고 있는 직류전위차법의 실험방법을 소개한다.

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Density Measurement for Continuous Flow Segment Using Two Point Detectors (두 개의 지점 검지기를 이용한 연속류 구간의 밀도측정 방안)

  • Kim, Min-Sung;Eom, Ki-Jong;Lee, Chung-Won
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.1
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    • pp.37-44
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    • 2009
  • Density is the most important congestion indicator among the three fundamental flow variables, flow, speed and density. Measuring density in the field has two different ways, direct and indirect. Taking photos with wide views is one of direct ways, which is not widely used because of its cost and lacking of proper positions. Another direct density measuring method using two spot detectors has been introduced with the concept of instantaneous density, average density and measurement interval. The relationship between accuracy and measurement interval has been investigated using the simulation data produced by Paramics API function. Finally, density measurement algorithm has been suggested including exponential smoothing for device development.

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Coupling Metrics for Web Pages Clustering in Restructuring of Web Applications (웹 어플리케이션 재구조화를 위한 클러스터링에 사용되는 결합도 메트릭)

  • Lee, En-Joo;Park, Gen-Duk
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.3
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    • pp.75-84
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    • 2007
  • Due to the increasing complexity and shorter life cycle of web applications, web applications need to be restructured to improve flexibility and extensibility. These days approaches are being used where systems are understood and restructured through clustering techniques. In this paper, the coupling metrics are proposed for clustering web pages more effectively. To achieve this, web application models are defined, where the relationship between web pages and the numbers of parameters are included. Considering direct and indirect coupling strength based on these models, coupling metrics are defined. The more direct relations between two pages and the more parameters they have, the stronger direct coupling is. The higher indirect connectivity strength between two pages is, the more similar the patterns of relationships among other web pages are. We verify the suggested metrics according to the well known verification framework and provide a case study to show that our metrics complements some existing metrics.

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Deformation Based Seismic Design of Asymmetric Wall Structures (변형에 기초한 비대칭 벽식 주초의 내진설계)

  • 홍성걸;조봉호
    • Journal of the Earthquake Engineering Society of Korea
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    • v.6 no.1
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    • pp.43-53
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    • 2002
  • Current torsional provisions focus n restricting torsional effect of asymmetric wall structures by proportioning strength of wall based on the traditional assumption that stiffness and strength are independent. Recent studies have pointed out that stiffness of structural wall is dependent on the strength. This implies that actual stiffness of walls can be determined only after torsional design is finished and current torsional provisions may result in significant errors. To overcome this shortcoming, this paper proposes deformation based torsional design for asymmetric wall structures. Contrary to the current torsional provisions, deformation-based torsional design uses displacement and rotation angle as design parameters and calculates base shear for inelastic torsional response directly. Main purpose of deformation based torsional design is not to restrict torsional response but to ensure intended torsional mechanism according to the capacity design concept. Because displacement and rotation angle can be used as performance criteria indicating performance level of asymmetric structures, this method can be applied to the performance based seismic design effectively.

1 YEAR FOLLOW-UP STUDY OF DIRECT AND INDIRECT COMPOSITE RESTORATIONS (직접법과 간접법으로 수복한 복합레진의 1년간의 임상적인 평가)

  • Park, Sung-Ho
    • Restorative Dentistry and Endodontics
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    • v.27 no.3
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    • pp.284-289
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    • 2002
  • Background : The purpose of the present study was to evaluate the direct and indirect composite restorations which had been placed for 1 year Methods : The composite restorations which had been placed between 1999. Mar and 1999, Dec was evaluated after 1 year For direct restorations. Spectrum (Dentsply, USA) and Z100 (3M, USA) were used in the anterior teeth and Surefil (Dentsply, USA) were used. For class V restorations of anterior and posterior teeth. Spectrum was used. For indirect restorations, Targis/Vectris system (Vivadent/Ivoclar, Liechtenstein) was used 2 examiners evaluated marginal quality, proximal contact. discoloration, presence of 2$^{nd}$ caries, loss of filling and hypersensitivity of restorations. The restorations was clinically evaluated by modified methods based on USPHS. Results : 60 teeth were evaluated. 59 were clinically acceptable and 1 restoration which was placed in class v cavity in the posterior tooth was fallen out. In most cases, the restorations were clinically accept-able. For restorations which had been directly placed in the class II cavities, loose proximal contact was indicated as the main complaints. Conclusions : Most of Anterior and posterior restorations which bad been directly or indirectly placed for 1 year were clinically acceptable. For posterior teeth, loose proximal contact was indicated as the main problem in the directly placed Class II restorations. Long term clinical study is needed.

The Writing Requirement of Contracts for International Sales of Goods: the CISG and the US Laws (국제물품매매계약에서의 서면요건에 대한 고찰: 미국계약법과 CISG 비교를 중심으로)

  • Ha, Choong-Lyong
    • International Commerce and Information Review
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    • v.14 no.4
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    • pp.203-225
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    • 2012
  • This paper investigates the difference of writing requirements between the UCC2. and the UN convention on international sales of goods (CISG). To do it, the U.S writing requirement by statute of frauds was introduced by two sources of laws including common law and UCC${\S}$2-201. Although the U.S. statute of frauds requires some contract to be written with formalities, the way the requirement is satisfied is quite flexible in terms of its formalities. The UCC is more flexible than the common law in its formalities. The CISG does not require the sales contract to be written with any format, which is totally different from the U.S statue of frauds. Such differences between the U.S laws and CISG in writing requirement were investigated in the context of conflicts of laws.

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Nuclear and Cytoplasmic Dynamics in Mammalian Oocytes during Sexual and Asexual Developments (포유동물 난자의 유성 및 무성 발생과정 동안 핵 및 세포질의 변화)

  • Kim, Nam-Hyung
    • Development and Reproduction
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    • v.4 no.1
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    • pp.7-12
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    • 2000
  • At fertilization, sperm penetrates into oocyte, male and female pronuclei are fused together, and mitotic division follows. However, little information is available on the interactive roles and dynamic processes between cytoplasmic and nuclear components during the pronuclear formation, migration and cell division. The assisted reproductive technologies such as, intracytoplasmic sperm injection (ICSI) and round spermatid injection(ROSI) could provides new treatments for the male infertility as well as tools for the study of basic mechanism during fertilization. Nuclear transfer can also provide a mechanism on the interactive roles between nucleus and cytoplasm since the process includes nuclear reprogrammming of differentiated cells in the enucleated oocytes. Recently, I have investigated developmental processes in porcine oocytes following fertilization parthenogenesis, ICSI, ROSI and nuclear transfer using indirect immunocytochemical and electron microscopic studies. The results could provide an insight into biological questions related with epigenesis as well as strategies for the enhancement of embryology in general such as ICSI and nuclear transfer.

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MEASUREMENT OF PULPAL BLOOD FLOW USING A LASER DOPPLER FLOWMETER (Laser Doppler flowmeter를 이용한 치수혈류 측정)

  • Ban, Tae-Whan;Lee, Jae-Sang;Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.24 no.4
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    • pp.560-569
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    • 1999
  • Blood supply rather than nerve supply implies pulp vitality. To evaluate pulp vitality clinically, electric pulp test and thermal test which are based on sensory nerve response have been used in addition to many auxiliary data such as past dental history, visual inspection, radiographic examination, percussion, palpation and transillumination test. However, reactivity of the nerves to the stimulation is not synonymous with normalcy. Therefore measurement of pulpal blood flow using a laser Doppler flowmeter became a new trial to test the pulp vitality. The purpose of the present study was to evaluate normal pulpal blood flow level of maxillary teeth in adult to provide a guideline in determining the vitality of dental pulp. Pulpal blood flow was measured in maxillary central and lateral incisors, canines, first and second premolars and first molars of seventy nine adults of 22 - 30 years old using a laser Doppler flowmeter (PeriFlux 4001, Perimed Co., Stockholm, Sweden, 780 nm infrared laser, 1mW). For directly-made splints, silicone rubber impressions were taken directly from the mouth. For indirectly-made splints, alginate impressions were taken from the mouth and stone cast were made. After making depressions on the buccal surfaces of the cast teeth to indicate the hole positions, second impressions with vinyl polysyloxane putty were taken from the cast. Holes for the laser probes were made at the putty impressions 4mm above the gingival level. Laser probe (PF416 dental probe, 1.5mm) was inserted in the prepared hole and the splint was set in the mouth. After 10 minutes of patient relaxing, pulpal blood flow was recorded for 5 minutes on each tooth. The recorded flow was saved in the computer and calculated with a software 'Perisoft' version 5.1. Pulpal blood flow was also recorded in six teeth of five individuals with no response to electric pulp test and cold test, with periapical radiolucency, or with history of root canal treatment to compare with nonvital teeth. The difference between the mean flow values of each group of teeth were analyzed using one-way ANOVA and Duncan's Multiple Range test. The results were as follows: 1. The average pulpal blood flow values of all the tested teeth of each location were between 9 - 16 Perfusion Unit. Pulpal blood flow value was highest in maxillary lateral incisors, followed by first premolars, second premolars, canines, central incisors, and then first molars (p<0.01). 2. In six anterior teeth, indirectly-made splint group showed higher pulpal blood flow values than directly-made splint group (p<0.01). In posterior teeth, however, there was no significant flow value difference between directly-made splint group and indirectly-made splint one (p>0.05). 3. Teeth with vital pulps showed higher signal values than teeth with nonvital pulps (p<0.01), and the flow photographs showed heartbeat-synchronous fluctuations and vasomotions, while those were absent in non vital tooth.

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