• 제목/요약/키워드: lattice relationship

검색결과 86건 처리시간 0.025초

A Note on Intuitionistic Fuzzy Subgroups

  • 안태천;장경원;노석범;허걸
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
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    • pp.496-499
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    • 2005
  • In this paper, We discuss various types of sublattice of the lattice of intuitionistic fuzzy subgroups of a given group. We Prove that a special class of intuitionistic fuf normal subgroups constitutes a modular sublattice of the lattice of intuitionistic fuzzy subgroups. Moreover, we exhibit the relationship of the sublattices of the lattice of intuitionistic fuzzy subgroups.

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Computationally Efficient Lattice Reduction Aided Detection for MIMO-OFDM Systems under Correlated Fading Channels

  • Liu, Wei;Choi, Kwonhue;Liu, Huaping
    • ETRI Journal
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    • 제34권4호
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    • pp.503-510
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    • 2012
  • We analyze the relationship between channel coherence bandwidth and two complexity-reduced lattice reduction aided detection (LRAD) algorithms for multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems in correlated fading channels. In both the adaptive LR algorithm and the fixed interval LR algorithm, we exploit the inherent feature of unimodular transformation matrix P that remains the same for the adjacent highly correlated subcarriers. Complexity simulations demonstrate that the adaptive LR algorithm could eliminate up to approximately 90 percent of the multiplications and 95 percent of the divisions of the brute-force LR algorithm with large coherence bandwidth. The results also show that the adaptive algorithm with both optimum and globally suboptimum initial interval settings could significantly reduce the LR complexity, compared with the brute-force LR and fixed interval LR algorithms, while maintaining the system performance.

시판 치과용 Au-Ag-Cu-Pd 합금의 등온시효경화거동 (Isothermal Age-hardening Behavior in the Commercial Dental Au-Ag-Cu-Pd Alloy)

  • 김형일;장명익;이유식
    • 대한의용생체공학회:의공학회지
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    • 제17권2호
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    • pp.247-254
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    • 1996
  • The relationship between the isothermal age-hardening behavior and the phase transformation in the commercial dental Au-Ag-Cu-Pd alloy was investigated Age-hardening was mostly attributed to the lattice distortions of the supersaturated w phase resulting from the transformation to the metastable phasel which were more distinct at lower aging temperature. The lattice distortions resulting from the transformation of the metastable phases to the equilibrium phases also made a contribution to the age-hardening.

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(SKEW) FILTERS IN RESIDUATED SKEW LATTICES: PART II

  • Koohnavard, Roghayeh;Saeid, Arsham Borumand
    • 호남수학학술지
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    • 제40권3호
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    • pp.401-431
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    • 2018
  • In this paper, some kinds of (skew) filters are defined and are studied in residuated skew lattices. Some relations are got between these filters and quotient algebras constructed via these filters. The Green filter is defined which establishes a connection between residuated lattices and residuated skew lattices. It is investigated that relationships between Green filter and other types of filters in residuated skew lattices and the relationship between residuated skew lattice and other skew structures are studied. It is proved that for a residuated skew lattice, skew Hilbert algebra and skew G-algebra are equivalent too.

FUZZY $\sigma$-IDEALS OF $\sigma$-LATTICES

  • IN BYUNG SIK
    • Journal of applied mathematics & informatics
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    • 제17권1_2_3호
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    • pp.633-641
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    • 2005
  • We investigate the relationship between fuzzy $\sigma$-ideals and fuzzy congruence on a distributive $\sigma$-lattice and obtain some useful results.

V2O5/TiO2 촉매의 선택적 환원촉매반응에서 격자산소의 역할 (The Role of Lattice Oxygen in the Selective Catalytic Reduction of NOx on V2O5/TiO2 Catalysts)

  • 하헌필;최희락
    • 한국재료학회지
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    • 제16권5호
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    • pp.323-328
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    • 2006
  • In situ electrical conductivity measurements on $V_2O_5WO_3/TiO_2$ catalysts were carried out at between 100 and $300^{\circ}C$ under pure oxygen, NO and $NH_3$ to investigate the reaction mechanism for ammonia SCR (selective catalytic reduction) de NOX. The electrical conductivity of catalysts changed irregularly with supply of NO. It was, however, found that the electrical conductivity change with ammonia supply was regular and the increase of electrical conductivity was mainly caused by reduction of the labile surface oxygen. The electrical conductivity change of catalysts showed close relationship with the conversion rate of NOx. Variation of conversion rate in atmosphere without gaseous oxygen also showed that labile lattice oxygen is indispensable in the initial stage of the de NOx reaction. These results suggest that liable lattice oxygen acts decisive role in the de NOx mechanism. They also support that de NOx reaction occurs through the Eley?Rideal type mechanism. The amount of labile oxygen can be estimated from the measurement of electrical conductivity change for catalysts with ammonia supply. This suggests that measurement of the change can be used as a measure of the de NOx performance.

The recombination velocity at III-V compound heterojunctions with applications to Al/$_x$/Ga/$_1-x$/As-GaAs/$_1-y$/Sb/$_y$/ solar cells

  • 김정순
    • 전기의세계
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    • 제28권4호
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    • pp.53-63
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    • 1979
  • Interface recombination velocity in $Al_{x}$G $a_{1-x}$ As-GaAs and $Al_{0.85}$, G $a_{0.15}$ As-GaA $s_{1-y}$S $b_{y}$ heterojunction systems is studied as a function of lattice mismatch. The results are applied to the design of highly efficient III-V heterojunction solar cells. A horizontal liquid-phase epitaxial growth system was used to prepare p-p-p and p-p-n $Al_{x}$G $a_{1-x}$ As-GaA $s_{1-y}$S $b_{y}$-A $l_{x}$G $a_{1-x}$ As double heterojunction test samples with specified values of x and y. Samples were grown at each composition, with different GaAs and GaAs Sb layer thicknesses. A method was developed to obtain the lattice mismatch and lattice constants in mixed single crystals grown on (100) and (111)B oriented GaAs substrates. In the AlGaAs system, elastic lattice deformation with effective Poisson ratios .mu.$_{eff}$ (100=0.312 and .mu.$_{eff}$ (111B) =0.190 was observed. The lattice constant $a_{0}$ (A $l_{x}$G $a_{1-x}$ As)=5.6532+0.0084x.angs. was obtained at 300K which is in good Agreement with Vegard's law. In the GaAsSb system, although elastic lattice deformation was observed in (111) B-oriented crystals, misfit dislocations reduced the Poisson ratio to zero in (100)-oriented samples. When $a_{0}$ (GaSb)=6.0959 .angs. was assumed at 300K, both (100) and (111)B oriented GaAsSb layers deviated only slightly from Vegard's law. Both (100) and (111)B zero-mismatch $Al_{0.85}$ G $a_{0.15}$As-GaA $s_{1-y}$S $b_{y}$ layers were grown from melts with a weight ratio of $W_{sb}$ / $W_{Ga}$ =0.13 and a growth temperature of 840 to 820 .deg.C. The corresponding Sb compositions were y=0.015 and 0.024 on (100) and (111)B orientations, respectively. This occurs because of a fortuitous in the Sb distribution coefficient with orientation. Interface recombination velocity was estimated from the dependence of the effective minority carrier lifetime on double-heterojunction spacing, using either optical phase-shift or electroluminescence timedecay techniques. The recombination velocity at a (100) interface was reduced from (2 to 3)*10$^{4}$ for y=0 to (6 to 7)*10$^{3}$ cm/sec for lattice-matched $Al_{0.85}$G $a_{0.15}$As-GaA $s_{0.985}$S $b_{0.015}$ Although this reduction is slightly less than that expected from the exponential relationship between interface recombination velocity and lattice mismatch as found in the AlGaAs-GaAs system, solar cells constructed from such a combination of materials should have an excellent spectral response to photons with energies over the full range from 1.4 to 2.6 eV. Similar measurements on a (111) B oriented lattice-matched heterojunction produced some-what larger interface recombination velocities.ities.ities.s.

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세 명의 사용자의 간섭 채널을 위한 협력 다중점 송수신(CoMP)에서의 격자(Lattice) 부호 간섭 정렬 (Lattice Code of Interference Alignment for Interference Channel with 3 Users in CoMP)

  • 이문호;펑부스
    • 대한전자공학회논문지TC
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    • 제49권6호
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    • pp.27-38
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    • 2012
  • 본 논문에서는 최근 스마트 폰의 급격한 보급과 음성 위주의 이동 통신 서비스가 무선 멀티미디어 콘텐츠를 중심으로 하는 데이터 위주의 서비스로 전환되고 있음을 보였고, 셀 서비스 문제인 음영(shadowing) 지역을 해결할 수 있는 방안으로 다중점 송수신(CoMP:Coordinated Multi-Point Transmission and Reception) 기법을 소개하였다. 간섭 신호의 영향을 줄이기 위해서는 원하지 않는 간섭 신호를 직교하도록 제어하는 것이 이상적이지만, 현실적인 응용에서는 간섭을 정렬하거나 회피하는 방법이 이용된다. 간섭을 적이 아닌 친구처럼 대할 수 있도록 하는 방법이 간섭 정렬 기법이다. 강한 간섭이 존재하는 가우시안 채널 에서 격자 부호가 랜덤 부호처럼 Shannon 채널 용량을 달성할 수 있음을 확인하였고, 세 명의 사용자가 존재하는 대칭 간섭 채널의 간섭 정렬에 격자 부호를 적용하여 채널 매개 변수 a와 자유도(DoF:Degree of Freedom)의 상관관계를 보였다.

Mg-Zn-Y 합금에서 준결정 및 준결정 유사상 (Quasicrystals And Related Approximant Phases in Mg-Zn-Y)

  • 박은수;옥재범;김원태;김도향
    • Applied Microscopy
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    • 제32권1호
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    • pp.31-37
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    • 2002
  • [ $Mg_{68}Zn_{28}Y_4$ ] 합금의 응고 조직은 primary solidification phase, primary solidification phase로부터 성장된 ${\alpha}-Mg$ dendrite, 그리고 응고 말기에 형성된 eutectic structure의 세 가지형태 조직으로 구성되어져 있다. Primary solidification phase에는 매우 큰 정도의 phason strain이 존재하고 있으며, $a=27.2{\AA}\;and\;{\alpha}=63.43^{\circ}$의 격자상수를 갖는 1/1 rhombohedral approximant가 존재한다. 이와 같은 rhombohedral approximant의 구조는 six dimensional face centered hyper-cubic lattice에 phason strain을 도입함에 의해 얻어질 수 있다. Decagonal phase는 icosahedral phase로부터 방위 관계를 가지며 형성되며, $Mg_4Zn_7$는 decagonal phase로부터 방위관계를 가지며 성장한다. 이는 세 상간에 구조적 유사성이 존재하고 있음을 의미하며, 응고시 용질원자의 분배에 의해 이들 세 상이 순서대로 형성되어진다.