• Title/Summary/Keyword: weak specification

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DYNAMICAL SYSTEMS WITH SPECIFICATION

  • Lee, Keonhee;Tajbakhsh, Khosro
    • Journal of the Chungcheong Mathematical Society
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    • v.28 no.1
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    • pp.103-108
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    • 2015
  • In this paper we prove that $C^1$-generically, if a diffeomorphism f on a closed $C^{\infty}$ manifold M satisfies weak specification on a locally maximal set ${\Lambda}{\subset}M$ then ${\Lambda}$ is hyperbolic for f. As a corollary we obtain that $C^1$-generically, every diffeomorphism with weak specification is Anosov.

POSITIVE EXPANSIVITY, CHAIN TRANSITIVITY, RIGIDITY, AND SPECIFICATION ON GENERAL TOPOLOGICAL SPACES

  • Devi, Thiyam Thadoi;Mangang, Khundrakpam Binod
    • Bulletin of the Korean Mathematical Society
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    • v.59 no.2
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    • pp.319-343
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    • 2022
  • We discuss the notions of positive expansivity, chain transitivity, uniform rigidity, chain mixing, weak specification, and pseudo orbital specification in terms of finite open covers for Hausdorff topological spaces and entourages for uniform spaces. We show that the two definitions for each notion are equivalent in compact Hausdorff spaces and further they are equivalent to their standard definitions in compact metric spaces. We show that a homeomorphism on a Hausdorff uniform space has uniform h-shadowing if and only if it has uniform shadowing and its inverse is uniformly equicontinuous. We also show that a Hausdorff positively expansive system with a Hausdorff shadowing property has Hausdorff h-shadowing.

Reliability prediction of electronic components on PCB using PRISM specification (PRISM 신뢰성 예측규격서를 이용한 전자부품(PCB) 신뢰도 예측)

  • Lee, Seung-Woo;Lee, Hwa-Ki
    • Journal of the Korea Safety Management & Science
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    • v.10 no.3
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    • pp.81-87
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    • 2008
  • The reliability prediction and evaluation for general electronic components are required to guarantee in quality and in efficiency. Although many methodologies for predicting the reliability of electronic components have been developed, their reliability might be subjective according to a particular set of circumstances, and therefore it is not easy to quantify their reliability. In this study reliability prediction of electronic components, that is the interface card, which is used in the CNC(Computerized Numerical Controller) of machine tools, was carried out using PRISM reliability prediction specification. Reliability performances such as MTBF(Mean Time Between Failure), failure rate and reliability were obtained, and the variation of failure rate for electronic components according to temperature change was predicted. The results obtained from this study are useful information to consider a counter plan for weak components before they are used.

A study on the improvement of The standard specifications for Mock-up Test in the Curtain-wall construction (Curtain-wall공사에 있어서 Mock-up Test 건축공사표준시방서의 개선 방안에 관한 연구)

  • Lee Jin-Man;Kang Jae-Wang;Son Yong-Geun;Kim Chang-Duk
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.491-494
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    • 2003
  • Curtain wall (for the outside wall) must be designed and constructed to resist weather condition of nature like rain. wind and surrounding environment. So, Now days, Mock-up test of curtain wall's total capability is generally used for skycraft building. But, Mock-up test specification in korea is so weak that there are lots of disputation. Also, lacking of clearness in specification causes many trouble in adaptation. Therefore, I would like to consider the problem of Mock-up test specification by inspecting and comparing with other country's works. and I will mention the way of approvement in our specification.

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The Variation of Slope Stability by Ground Water Level in Railway Lines (지하수위에 따른 철도사면의 안정성 변화)

  • Kim, Hyun-Ki;Shin, Min-Ho;Shin, Ji-Soo
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.789-795
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    • 2008
  • Slope stability is affected by various factors. For safety management of slopes, monitoring systems have been widely constructed along railway lines. The representative data from the systems are variations of ground profile such like ground water level and pore water pressure etc. and direct displacement measured by ground clinometer and tension wire sensor. Slopes are mainly effected by rainfall and rainfall causes the decrease of factor of safety(FOS). Because FOS varies linearly by the variation of ground water level and pore pressure, it has a weak point that could not define the time and proper warning sign to secure the safety of the train. In this study, alternative of FOS such as reliability index and probability of failure is applied to slope stability analysis introducing the reliability concept. FOS, reliability index, probability of failure and velocity of probability of failure of the slopes by variation of ground water level are investigated for setting up the specification of safety management of slopes. By executing case study of a slope(ILLO-IMSUNGLI), it is showed to be applied to specification of safety management.

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A Study of PCI (Physical Cell Identification) Assignment in LTE (Long Term Evolution) SON (Self-Organization Network) (LTE 자가 구성 네트워크망에서 물리적 셀 ID할당 방법 연구)

  • Yang, Mochan
    • Journal of IKEEE
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    • v.23 no.3
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    • pp.941-946
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    • 2019
  • In this paper, the author analyzed the PCI (Physical Cell Identification) allocation methods in the LTE (Long Term Evolution) SON (Self Organization Network) environment. A variety of techniques have been proposed for how to allocate PCI, and the LTE standard fundamentally explained that collision between a cell and neighbor cells arise while a cell assign the PCI. Therefore, in this paper, the author examined the scenarios of PCI collision, weak collision, and confusion proposed by LTE specification. In addition, the cell central approach and the distributed approach were discussed as solutions for each scenario. In this paper, the author reviewed the approach of graphic coloring technique which was studied recently and explained the strategy of central approach.

Formal Semantics for Processing Exceptions (예외 처리를 위한 형식 의미론)

  • Han, Jung-Lan
    • The KIPS Transactions:PartA
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    • v.17A no.4
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    • pp.173-180
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    • 2010
  • To specify a formal semantics is to do a significant part for design, standardization and translation of programming languages. The existing studies of a formal semantics for Java have a weak point to describe a clear and practical semantics for an efficient translation. It is necessary to do research for a formal semantics to specify a static and dynamic semantics clearly in order to do an efficient translation. This paper presents the improved Action Equation that specifies a formal semantics for Java to extend the research using Action Equation. The Action Equation is a practical and accurate specification that describes object-oriented programming features and handles exceptions. The specified Action Equation is compared to other descriptions, in terms of readability, modularity, extensibility, and flexibility and then we verified that Action Equation is superior to other formal semantics.

Radiative Transfer Simulation of Microwave Brightness Temperature from Rain Rate

  • Yoo, Jung-Moon
    • Journal of the Korean earth science society
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    • v.23 no.1
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    • pp.59-71
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    • 2002
  • Theoretical models of radiative transfer are developed to simulate the 85 GHz brightness temperature (T85) observed by the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) radiometer as a function of rain rate. These simulations are performed separately over regions of the convective and stratiform rain. TRMM Precipitation Radar (PR) observations are utilized to construct vertical profiles of hydrometeors in the regions. For a given rain rate, the extinction in 85 GHz due to hydrometeors above the freezing level is found to be relatively weak in the convective regions compared to that in the stratiform. The hydrometeor profile above the freezing level responsible for the weak extinction in convective regions is inferred from theoretical considerations to contain two layers: 1) a mixed (or mixed-phase) layer of 2 km thickness with mixed-phase particles, liquid drops and graupel above the freezing level, and 2) a layer of graupel extending from the top of the mixed layer to the cloud top. Strong extinction in the stratiform regions is inferred to result from slowly-falling, low-density ice aggregates (snow) above the freezing level. These theoretical results are consistent with the T85 measured by TMI, and with the rain rate deduced from PR for the convective and stratiform rain regions. On the basis of this study, the accuracy of the rain rate sensed by TMI is inferred to depend critically on the specification of the convective or stratiform nature of the rain.

An Auto-tuning Algorithm of PI Controller Using Time Delay Element (시간 지연 요소를 이용한 PI 제어기 자동 동조 알고리즘)

  • Oh, Seung-Rohk
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.47 no.6
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    • pp.1-5
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    • 2010
  • We propose an algorithm which can classify the system should use a PI controller, which have a weak high frequency attenuation characteristics near the critical frequency. To classify the system, we use a time delay element to calculate a gain attenuation rate near the critical frequency. The proposed algorithm also can design PI controller with the given magnitude margin and phase margin specification. The proposed algorithm uses time delay element and saturation function to identify the one point information in frequency domain. We justify the proposed algorithm via the simulation.

A Fundamental Property of Concrete Containing Atomized Steel Slag Fine Aggregate after Reforming Process (개질처리한 제강슬래그 잔골재 사용 콘크리트의 성질)

  • 문한영;유정훈;박영훈;김주용;윤표호;김얼
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.318-321
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    • 2003
  • Steel slag is produced during steel making process. Compared with the blast furnace slag, converter slag has the expansibility due to the reaction with water and free CaO. Therefore it is specified in Standard Specification for Concrete in Korea that steel slag aggregate must not be used in concrete. In this study, atomized steel slag aggregate is conducted from converter slag by the atomizing method. Atomized steel slag and conventional converter slag are same in its composite by nature in the converter but compounds of the composite become different because of different method of slag treatment. Especially atomized steel slag aggregate overcomes expansibility that is the weak point for usage. It is researched whether it has the possibility, suitability for fine aggregate in concrete. Slump and air content are measured in fresh concrete, compressive and bending strength in hardened concrete. These is compared with control concrete with washed sand.

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