• Title/Summary/Keyword: L2

Search Result 53,271, Processing Time 0.068 seconds

Two Dimensional Slow Feature Discriminant Analysis via L2,1 Norm Minimization for Feature Extraction

  • Gu, Xingjian;Shu, Xiangbo;Ren, Shougang;Xu, Huanliang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.12 no.7
    • /
    • pp.3194-3216
    • /
    • 2018
  • Slow Feature Discriminant Analysis (SFDA) is a supervised feature extraction method inspired by biological mechanism. In this paper, a novel method called Two Dimensional Slow Feature Discriminant Analysis via $L_{2,1}$ norm minimization ($2DSFDA-L_{2,1}$) is proposed. $2DSFDA-L_{2,1}$ integrates $L_{2,1}$ norm regularization and 2D statically uncorrelated constraint to extract discriminant feature. First, $L_{2,1}$ norm regularization can promote the projection matrix row-sparsity, which makes the feature selection and subspace learning simultaneously. Second, uncorrelated features of minimum redundancy are effective for classification. We define 2D statistically uncorrelated model that each row (or column) are independent. Third, we provide a feasible solution by transforming the proposed $L_{2,1}$ nonlinear model into a linear regression type. Additionally, $2DSFDA-L_{2,1}$ is extended to a bilateral projection version called $BSFDA-L_{2,1}$. The advantage of $BSFDA-L_{2,1}$ is that an image can be represented with much less coefficients. Experimental results on three face databases demonstrate that the proposed $2DSFDA-L_{2,1}/BSFDA-L_{2,1}$ can obtain competitive performance.

Synthesis and Characterization of C-meso and C-racemic Isomers of a Reinforced Tetraaza Macrocycle and Their Copper(II) Complexes

  • Jeong, Gyeong Rok;Kim, Juyoung;Kang, Shin-Geol;Jeong, Jong Hwa
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.7
    • /
    • pp.2043-2048
    • /
    • 2014
  • Two isomers of a new tetraaza macrotricycle 2,2,4,9,9,11-hexaazamethyl-1,5,8,12-tetraazatricyclo[$10.2.2^{5.8}$]-octadecane ($L^2$) containing additional N-$CH_2CH_2$-N linkages, C-meso-$L^2$ and C-racemic-$L^2$, have been prepared by the reaction of 1-bromo-2-chloroethane with C-meso-$L^1$ or C-racemic-$L^1$ ($L^1$ = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). Both C-meso-$L^2$ and C-racemic-$L^2$ react with copper(II) ion to form $[Cu(C-meso-L^2)]^{2+}$ or $[Cu(C-racemic-L^2)]^{2+}$ in dehydrated ethanol, but do not with nickel(II) ion under similar conditions. Crystal structure of [Cu(C-racemic-$L^2$)($H_2O$)]$(ClO_4)_2$ shows that the complex has distorted square-pyramidal coordination geometry with an apically coordinated water molecule. Unexpectedly, the Cu-N distances [2.016(3)-2.030(3) ${\AA}$] of [Cu(C-racemic-$L^2$)($H_2O$)]$(ClO_4)_2$ are longer than those [1.992(3)-2.000(3) ${\AA}$] of [Cu(C-racemic-$L^1$)($H_2O$)]$(ClO_4)_2$. As a result, $[Cu(C-racemic-L^2)(H_2O)]^{2+}$ exhibits weaker ligand field strength than $[Cu(C-racemic-L^1)(H_2O)]^{2+}$. The copper(II) complexes readily react with CN- ion to yield the cyano-bridged dinuclear complex $[Cu_2(C-meso-L^2)_2CN]^{3+}$ or $[Cu_2(C-racemic-L^2)_2CN]^{3+}$. Spectra and chemical properties of $[Cu(C-meso-L^2)]^{2+}$ and $[Cu_2(C-meso-L^2)_2CN]^{3+}$ are not quite different from those of $[Cu(C-racemic-L^2)]^{2+}$ and $[Cu_2(C-racemic-L^2)_2CN]^{3+}$, respectively.

Design of an Anti-Jamming Five-Element Planar GPS Array Antenna (재밍대응 5소자 평면 GPS 배열 안테나 설계)

  • Seo, Seung Mo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.25 no.6
    • /
    • pp.628-636
    • /
    • 2014
  • This paper describes the design and analysis of five-element planar array antenna of an anti-jamming satellite navigation system. We propose a design of multi-layer patch antenna for Global Positioning System(GPS) $L_1/L_2$ dual bands. The proposed antenna has two ports feeding network with a hybrid chip coupler for a broad bandwidth with Right-Handed Circular Polarization(RHCP). The measurement results show the bore-sight gains of 1.10 dBic($L_1$) and 0.37 dBic($L_2$) for the center element. The bore-sight gains of an edge element are 0.99 dBic($L_1$) and -0.57 dBic($L_2$). At a fixed elevation angle of $30^{\circ}$, antennas show average gains of -2.08 dBic ($L_1$) and -5.33 dBic($L_2$) for the center element, and average gains of -0.40 dBic($L_1$) and -2.09 dBic($L_2$) for the edge elements. The results demonstrate that the proposed array antenna is suitable for anti-jamming applications.

Studies on Production of Heteropolysaccharide by Mutant of Xanthomonas malvacearum (Xanthomonas malvacearum 돌연변이주(突然變異株)의 Heteropolysaccharide 생산성(生産性)에 관(關)하여)

  • Lee, Ke-Ho;Kim, Mi-Sun;Park, Chan-Yung
    • Applied Biological Chemistry
    • /
    • v.30 no.1
    • /
    • pp.77-87
    • /
    • 1987
  • The mutant with high productivity, X. malvacearum SNUF 560-6, was acquired from the X. malvacearum SNUF 560 with low productivity by UV-light irradiation. It was preserved is lyophilized stock culture and it was transferred to PDA slant to maintain viability fortnightly. Fermentations were started by retransfering to MY agar slant from PDA stok culture. The experiments for optimal xanthan gum production were studied in a chemically defined medium. Of the carbon and nitrogen sources tested, 0.4% sucrose medium and 10mM glutamic acid medium yielded the highest xanthan gun production respectively. The addition of 10g/l succinic acid stimulated xanthan gum production. Also 65mM $PO_4\;^{-3}\;(12.6g/l\;KH_2PO_4)$ was effective on xanthan gum production. Finally, medium 1 and medium 2 which have high xanthan gum production potencies were achieved in this stud. The components of medium 1 and medium 2 were as follows: Medium 1 : sucrose 40g/l glutamate 10mM $PO_4\;^{-3}\;54mM\;(KH_2PO_4\;12.65g/l)$ Citrate 2g/l $MgSO_4{\cdot}7H_2O\;0.2g/l$ $H_3BO_3\;0.005/l$ ZnO 0.006/l $FeCl_2{\cdot}6H_2O\;0.0024g/l$ $CaCO_3\;0.02g/l$ Medium 2 : $Sucrose\;40g/l\;(NH_4)_2SO_4\;2g/l$ $PO_4\;^{-3}\;65mM\;(KH_2PO_4\;12.65g/l)$ Succinate 10g/l $MgSO_4{\cdot}7H_2O\;0.02g/l$ $H_3BO_3\;0.06g/l$ ZnO 0.006g/l $FeCl_2{\cdot}6H_2O\;0.0024g/l$ $CaCO_3\;0.02g/l$.

  • PDF

Exploring the nature of communication anxiety in English among Korean EFL undergraduates (한국 대학생의 영어 의사소통 긴장감 연구)

  • Kim, Seung-Jung
    • English Language & Literature Teaching
    • /
    • v.13 no.4
    • /
    • pp.211-231
    • /
    • 2007
  • Communication anxiety (CA) in L2 has been identified as one of the important predictors of determining success in the attainment of L2 communication competence. L2 professionals have attempted to explicate its nature in L2, but seemingly failed to achieve the goal. This is probably because they have tended to rely on studies dependent on the use of surveys, which are usually constructed on the basis of their own perspectives rather than L2 students' on CA. To solve this problem, some L2 professionals have utilized diverse research methods that can gather opinions directly from L2 students who are the main constituent in L2 learning; regretfully, they have barely listened to L2 students' voices about controlling CA in L2. This descriptive study explored the nature of CA and the way of controlling it by analyzing data from 57 Korean EFL undergraduates who voluntarily responded to the oral interview questions. The findings of this study pointed out that CA in L2 negatively influenced L2 performance. However, it seemed to have the potential to promote L2 learning. Provided are some important implications that can assist L2 teachers to help their students control CA by maximizing the positive nature of CA.

  • PDF

Nuclear LS-Energy Matrix Elements with the Harmonic Oscillator Shell Model Wave Functions for the Configurations ($I_1$$I_{1+1}$$I_1$$I_{1+1}$) and Sum Rules (조화 단진동자 파동함수를 쓴 원자핵의 LS에너지 행열요소 합법칙)

  • Chung-hum Kim;Soon-Kwon Nam
    • Nuclear Engineering and Technology
    • /
    • v.14 no.1
    • /
    • pp.22-40
    • /
    • 1982
  • The nuclear LS-energy matrix elements have been calculated with the harmonic oscillator shell model wave functions for the configurations ( $l_{i}$ $l_{i+1}$$l_{i}$ $l_{i+1}$) where 1$_1$= $l_{s}$ , $l_2$=lp, $l_3$=ld, 2s, $l_4$=1f, 2p, $l_{5}$ =1g, 2d, 3s. The resulting matrix elements are expressed in terms of both Talmi integrals $I_1$ and Slater integrals $F^{k}$ . In addition to this various sum rules are derived and applied to check the results of the calculations.ons.

  • PDF

(L,M)-NEIGHBORHOOD SPACES

  • Kim, Y.C.;Ramadan, A.;Usama, M.A.
    • Korean Journal of Mathematics
    • /
    • v.15 no.2
    • /
    • pp.121-133
    • /
    • 2007
  • We introduce the notions of (L,M)-neighborhood spaces and (2,M)-fuzzifying neighborhood spaces. We investigate the relations among (L,M)-neighborhood spaces, (L,M)-topological spaces and (2,M)-fuzzifying neighborhood spaces.

  • PDF

Correlator Design for L1/L2C GPS Signal

  • Chang, Jae-Won;Kim, Keun-Taek;Lee, Sang-Jeong
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.2623-2626
    • /
    • 2003
  • GPS provides two services which include SPS(Standard Positioning Service) and PPS(Precise Positioning Service). While SPS users can navigate in more precise due to cancellation of SA(Selective Availability), SPS users has still less precision navigation than PPS users. L1/L2CS integrated receiver can provide more precise navigation to SPS users because the delay of Ionosphere will be cancelled by using two frequencies (L1 and L2). This paper designs an integrated L1/L2CS digital correlator to prepare the L2C signal that will be provided in 2003. Also L2CS transmitter is designed to confirm L2CS correlator.

  • PDF

A Study on the Precipitation Behavior of $Al_2Ti$ Phase in $L1_0$-TiAl and $L1_2-(Al,Cr)_3Ti$ ($L1_0$-TiAl 및 $L1_2-(Al,Cr)_3Ti$ 중에 $Al_2Ti$상의 석출거동에 관한 연구)

  • Han, Chang-Suk
    • Journal of the Korean Society for Heat Treatment
    • /
    • v.21 no.1
    • /
    • pp.20-25
    • /
    • 2008
  • Structural studies have been performed on precipitation hardening and microstructural variations found in Ti-Al-Cr ternary $L1_0$- and $L1_2$-phase alloys using transmission electron microscopy. Both the $L1_0$ and $L1_2$ phase alloys harden by aging at 973 K after solution annealing at higher temperatures. The amount of age hardening of the $L1_2$ phase alloy is larger than that of the $L1_0$ phase alloy. The phase separation between $L1_0$ and $L1_2$ phase have not been observed by aging at 973 K. But $Al_2Ti$ was formed in each matrix alloy during aging. The crystal structure of the $Al_2Ti$ phase is a $Ga_2Zr$ type in the $L1_0$ and a $Ga_2Hf$ type in the $L1_2$ phase, respectively. At the beginning of aging the fine coherent cuboidal $Al_2Ti$-phase are formed in the $L1_0$ phase. By further aging, two variants of $Al_2Ti$ precipitates grow along the two {110} habit planes. On the other hand, in the $L1_2$ phase, the $Al_2Ti$ phase forms on the {100} planes of the $L1_2$ matrix lattice. After prolonged aging the precipitates are rearranged along a preferential direction of the matrix lattice and form a domain consisting of only one variant. It is suggested that the precipitation of $Al_2Ti$ in each matrix alloy occurs to form a morphology which efficiently relaxes the elastic strain between precipitate and matrix lattices.

Mixed Convection Heat Transfer from Vertical In-Line Plates (수직 배열된 평판에서 혼합대류 열전달)

  • Kim, S.Y.;Ree, J.S.;Kwon, S.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.3 no.2
    • /
    • pp.123-130
    • /
    • 1991
  • The mixed convection heat transfer from vertical inline plates has been studied numerically by the finite difference method and experimentally with Mach-Zehnder interferometer. The dimensionless spacing, $s/L_1$, the relative length, $L_2/L_1$ and the dimensionless temperature ratio, ${\Phi}_2/{\Phi}_1$ are varied parametically. The lower plate mean Nusselt numbers show same values as $s/L_1$, ${\Phi}_2/{\Phi}_1$ and $L_2/L_1$ increase. The upper plate mean Nusselt numbers increase as $s/L_1$ and ${\Phi}_2/{\Phi}_1$ increase, but $L_2/L_1$ decreases. The upper plate mean Nusselt number is higher than the lower plate mean Nusselt for $s/L_1$ 1.8 at Re=100, $Gr=10^4$, Pr=0.71, $L_2/L_1=0.5$ and ${\Phi}_2/{\Phi}_1=1.0$. A comparison between the experimental and numerical results show good agreement.

  • PDF