• 제목/요약/키워드: property change

검색결과 1,970건 처리시간 0.028초

Zone Routing Protocol의 Ad-hoc네트워크 적용에 관한 연구 (A study on the Ad-hoc Network Application of Zone Routing Protocol)

  • 이영노;김용득
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 하계종합학술대회 논문집(1)
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    • pp.119-122
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    • 2004
  • This mobile oriented Ad-hoc network yet steps on development level, related issues and standardization are progressing. This paper presented ad-hoc network's overview and overall property, followed by routing scheme that must be setup for communication between each nodes. Among several routing scheme proposed for standardization, ZRP that is foaled by this paper, is hybrid type algorithm, and only includes advantages of others This paper presented running process and implementation method, result that is made from network simulation, shows analysis of each parameter values's change. Each parameters changed with many differences according to Zone radius and communication node's location from simualtion that was performed changing a number of nodes and a velocity of nodes.

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Hertz 접촉 문제의 유한 요소 해석 (Finite Element Analysis of Hertzian Contact Problem)

  • 고동선;김형종
    • 산업기술연구
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    • 제28권A호
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    • pp.81-88
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    • 2008
  • Generally, Hertz theory is used to analyze the contact problem of two bodies. It is simple derivation of solution in the contact part. And calculation time is short Moreover, it can mean well that many wear occurs relatively. However, material property becomes plastic deformation when large perpendicular pressure acts on a small contact surface product. In this case, Hertz theory is inapplicable. Therefore this thesis carried the finite element analysis in consideration of material elasticitystrain and the shape of the geometric from contact point. And it compared with Hertz theory that change of the contact surface and contact pressure.

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A Study on an Effective Process Strategy Model of Interactive Advertising in Smart Media

  • Ahn, Jong Bae
    • International Journal of Internet, Broadcasting and Communication
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    • 제12권1호
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    • pp.45-54
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    • 2020
  • One of the typical characteristics of smart media is that it is interactive, which shows a different form and property from the existing mass media, and also changes the way users use it. This change requires a different system from the existing method in the advertising process strategic model for effective interactive advertising in smart media. We attempted to derive an effective smart media interactive advertising process strategic model by understanding the interactive advertising processin smart media that is expected to continue to grow asthe main market of the advertising market and identifying the constituent factors. To this end, We analyzed the preminiary research results of interactive advertising and organized expert panels for the Delphi method and reflected their opinions and evaluations. The components and factors of interactive advertising were found and the effective interactive advertising process strategy model in smart media was derived from this study.

골격근의 노화에 대한 고찰 (A Review of Journals on the Aging Skeletal Muscle)

  • 권오봉;송윤경;임형호
    • 대한추나의학회지
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    • 제4권1호
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    • pp.55-65
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    • 2003
  • The purpose of this article was to contribute to the knowledge of physiological and pathological changes of aging skeletal muscles, and of therapic method. By aging there were changes of distribution of muscle fibers, the loss of muscle mass, the loss of the number of muscle fibers, the loss of glycolysis capacity, the decrease of the oxidative enzymes and muscle vascularization in the skeletal muscles. And as a pathological change, the exhaustive maximal exercise increased oxidative stress that led to oxidative damage which were shown to be implicated in promoting aging. The property of intensity and duration exercise is important not only in keeping human health and physical fitness from oxidative stress, but also for the maintenance of well-being and quality of life.

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두 이상기체 단순계로 구성된 복합계의 열역학적 거동 (Thermodynamic behavior of the composite system composed of two simple ideal gas systems)

  • 정평석;조경철
    • 대한기계학회논문집B
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    • 제22권6호
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    • pp.832-839
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    • 1998
  • The potential work is defined as the maximum available work extractable from a composite system. It is important concept to understand the behavior of a composite system because it is a property of the composite system and shows the possible room for the system to change its state by itself. To explain this concept quantitatively, the behavior of a composite system composed of two simple ideal gas systems is analyzed. The potential work of the composite system is estimated, the various reversible processes from a given state to the equilibrium state and the processes on which potential works are constant are shown on the T-P and S-V planes. Such an effort will be necessary to understand and characteristics of composite systems as well as helpful for a deeper comprehension of the energy conversion principles.

Sol-Gel법에 의한 강유전체 Pb(Zr, Ti)$O_3$의 제조 및 특성에 관한 연구 (Investigation on the property and preparation of ferroelectric Pb(Zr,Ti)$O_3$ by Sol-Gel method)

  • 임정한;김영식;장복기
    • E2M - 전기 전자와 첨단 소재
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    • 제7권6호
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    • pp.496-503
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    • 1994
  • In recent years Sol-Gel processing provides an interesting alternative method for the fabrication of ferroelectric thin layers and powder. PZT powder was prepared from an alkoxide-based solution by a Sol-Gel method. Gelation of synthesized complex solutions, microstructure, thermal analysis and crystallization behaviors of the calcined powder were studied in accordance with a water content and a catalyst. Especially gelation and crystallization behavior were analysed with the change of pH. The gelation time decreased as the pH of the mixed solution increased. For PZT powder with 650.deg. C heat treatment, 100% perovskite phase was formed by using either acidic or basic catalyst. By using either acidic or basic catalyst, we were able to get very fine powders of uniform shape with an average particle size of 0.8-1.mu.m.

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호텔기업의 인적자원 관리에 관한 연구 (A Study on the effect management of human resource in Hotel)

  • 류진순
    • 한국조리학회지
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    • 제6권2호
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    • pp.199-225
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    • 2000
  • It is desirable that the management of human resources, as a strategy for the competition, should be the necessity for the hotel industries to survive in the rapid change and continuous development In other words, the management of enterprise provides the foundation to form human relationship, just as the hospitality industry operates with human relationship. Here by, all the problems out hotels have faced are that our hotels should look for a new human resources. The control of human resources in hotels means that if does not only satisfy hotels, employees, and guests but improves the personal ability. also it is important for the method of hotel operation as a management. Therefor, hotel managers have to get a good human resources, at the same time, improve the potential ability from them in order to get development for industries and a person. This study in the effective project for the human resources in hotels is relation to the organization of hotel sand he factor of human resources. This research if focused on the property of classification each factor in the control of human resources. according to the classification, the relationship and an effect are commonly made in groups of properties and are named respectively.

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탄소섬유 복합재료의 열사이클에 의한 물성치 변화에 관한 연구 (A study for multi thermal cycle effect on mechanical property change in carbon epoxy composite)

  • 최순권;박세만;박명균
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2000년도 춘계학술발표대회 논문집
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    • pp.43-48
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    • 2000
  • Composite materials have been increasingly used in automotive and aircraft industries, naturally leading to active researches on the materials. The carbon-epoxy composite is selected to study its thermal characteristics. During multiple thermal cycles composed of repeated cooling and heating variations of elastic constants are investigated to understand thermal effects on the carbon-epoxy composite. In this investigation longitudinal resonance method and flexural resonance method was used to characterize. The values of $E_1$ show small amount of increases depending on number of cycles of the thermal fatigue processes whereas values of $G_13$ do not indicate noticeable changes. Also, in cases of $E_2$ and $G_23$ their values decrease to a certain extend in initial stages after applications of thermal fatigue processes. However, the number of cycles of the applied thermal fatigue processes does not seem to affect their values.

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Effect of Abnormal Grain Growth and Heat Treatment on Electrical Properties of Semiconducting BaTiO3Ceramics

  • Lee, Joon-Hyung;Cho, Sang-Hee
    • 한국세라믹학회지
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    • 제39권1호
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    • pp.21-25
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    • 2002
  • Effect of abnormal grain growth and heat treatment time on the electrical properties of donor-doped semiconductive BaTiO$_3$ceramics was examined. La-doped BaTiO$_3$ceramics was sintered at 134$0^{\circ}C$ for different times from 10 to 600 min in order to change the volume fraction of the abnormal grains in samples. As a result, samples with different volume fraction of abnormal grain growth from 22 to 100% were prepared. The samples were annealed at 120$0^{\circ}C$ for various times. The resistivity of the sam-ples at room and above Curie temperature was examined. The complex impedance measurement as functions of the volume fraction of abnormal grains and annealing time was conducted. Separation of complex impedance semicircle was observed in a sample in which abnormal and fine grains coexist. The results are discussed from a viewpoint of microstructure-property relationship.

이온도금된 Ti(C, N)피막의 물성에 대한 전자빔가열 효과 (Effects of Electron Beam Heating(EBH) on the Properties of ion Plated Ti(C, N) Films)

  • 김치명;고경현;안재환;배종수;정형식
    • 한국표면공학회지
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    • 제28권5호
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    • pp.267-275
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    • 1995
  • Electron beam can provide convenient way to heat the substrate during Hollow Cathode Discharge (HCD) ion plating of Ti(C, N)films. Densification of columnar structrue is enhanced by longer duration of electron beam heating(EBH). While strong(111) texture is identified always to be formed, the amount of (200) oriented grains which coherently interfaced with carbide particles of the substrate increased with heating(EBH). In turns, these crystallogaphical change lead to the increase of micro hardness and adhesion of coating. Adhesion of Ti(C, N) films increased more dramatically in case of ASP30 substrate of which carbide particles dispersed more finely than M42. Therefore, it could be concluded that both the density of film and interfacial structure can affect the adhesion property. Overheating of substrate could be resulted in low adhesion resistance due to high residual stress developed in the film.

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