• Title/Summary/Keyword: B/A ratio

Search Result 7,199, Processing Time 0.041 seconds

Formation of Chlorophyll-Protein Complexes in Greening Rape Cotyledons (Greening에 따른 유채 자엽의 엽록소-단백질 복합체 형성)

  • 이진범
    • Journal of Plant Biology
    • /
    • v.26 no.2
    • /
    • pp.91-99
    • /
    • 1983
  • The formation of chlorophyll-protein complexes (CP-complexes) during the greening of rape cotyledons (Brassica napus cv. Yongdang) was investigated by the SDS-polyacrylamide gel electrophoresis. The total chlorophyll content and Chl a/b ratio were also determined. In addition, the effects of dark treatment on the CP-complex patterns during greening have been examined with respect to their photosynthetic electron transport activity. Greening has brought about the increasein total chlorophyll content and the decrease in Chl a/b ratio, but there have been no changes in Chl a/b ratio after 24 hrs of greening. The light-harvesting chlorophyll a/b-protein complex (LHCP-complex0 was predominant during the initial greening period. Thereafter, the amout of chlorophyll a-protein complex (CP I-complex) was gradually increased. Twenty-four-hr dark treatment immediately after illumination for 6 hrs and 12 hrs resulted in the increase of the Chl a/b ration and the CP I complex, otherwise the decrease of the LHCP-complex. The LHCP/CP I ratio was gradually decreased with further greening, and appeared no change after 48 hrs illumination. The investigation of the photosynthetic electron transport activity indicated that photosystem (PS) II activity (H2Olongrightarrowp-PD*+FeCy**) did not change, but the activity of PS I was increased suddenly due to the dark treatment. The data suggests that the increase of CP I-complex may result in that of P-700, that is, the increase of PS I activity.

  • PDF

Study on the fabrication and the growth mechanism of Bi-2223 superconducting phase by diffusion method (확산법에 의한 Bi-2223 초전도상의 제조 및 성장기구에 관한 연구)

  • 최성환;최효상;한태희;황종선;한병성
    • Electrical & Electronic Materials
    • /
    • v.7 no.4
    • /
    • pp.281-288
    • /
    • 1994
  • According to spread volume of B(BiPbCuO) layer, composition ratio and each stage of sintering process, we studied stability of high Tc superconductor phase and generation and growth movement of superconducting phase. The dual layer composed of SrCaCuO and BiPbCuO compound were prepared to develop the Bi-2223 superconductor[108K] through interaction and diffusion during sintering process. The dual layer samples were sintered at 830.deg. C for 0-210 hours. From the result, the optimum conditions were : spread volume(A:B=1:0.6), sintering time(210h) and composition ratio(A:S $r_{2}$C $a_{2}$C $u_{2}$- $O_{x}$, B:B $i_{1.9}$P $b_{0.5}$C $u_{3}$ $O_{y}$) at 830.deg. C.. C.C.C.

  • PDF

The effect of extinction ratio, chirp and SPM on transmission performance of directly modulated 2.5 Gbit/s transmitter (소광비, 처핑 및 자기위상변조가 2.5Gbit/s 직접변조한 DFB-LD의 전송성능에 미치는 영향)

  • 김근영;이용기
    • Korean Journal of Optics and Photonics
    • /
    • v.12 no.3
    • /
    • pp.212-218
    • /
    • 2001
  • We experimentally investigated the dependence of extinction ratio and chirp on bias current which was injected into DFB-LD in a directly modulated 2.5 Obitls transmitter. Through the abnormal dispersion transmission, we found that transmission power penalty is minimized at 8-10 dB extinction ratio (bias current at 1.5-1.8 fold above threshold current). Also, we discussed the relation between extinction ratio and self phase modulation (SPM) through the 240 km abnormal dispersion transmission. When SPM takes effect, we obtained the best receiver sensitivity for specific system configuration at 10.4 dB and 8.4 dB extinction ratio, below and above 200km transmission distance, respectively. ively.

  • PDF

Pull-Out Behaviour of Hooked End Steel Fibres Embedded in Ultra-high Performance Mortar with Various W/B Ratios

  • Abdallah, Sadoon;Fan, Mizi;Zhou, Xiangming
    • International Journal of Concrete Structures and Materials
    • /
    • v.11 no.2
    • /
    • pp.301-313
    • /
    • 2017
  • This paper presents the fibre-matrix interfacial properties of hooked end steel fibres embedded in ultra-high performance mortars with various water/binder (W/B) ratios. The principle objective was to improve bond behaviour in terms of bond strength by reducing the (W/B) ratio to a minimum. Results show that a decrease in W/B ratio has a significant effect on the bond-slip behaviour of both types of 3D fibres, especially when the W/B ratio was reduced from 0.25 to 0.15. Furthermore, the optimization in maximizing pullout load and total pullout work is found to be more prominent for the 3D fibres with a larger diameter than for fibres with a smaller diameter. On the contrary, increasing the embedded length of the 3D fibres did not result in an improvement on the maximum pullout load, but increase in the total pullout work.

Multi-band multi-scale DenseNet with dilated convolution for background music separation (배경음악 분리를 위한 확장된 합성곱을 이용한 멀티 밴드 멀티 스케일 DenseNet)

  • Heo, Woon-Haeng;Kim, Hyemi;Kwon, Oh-Wook
    • The Journal of the Acoustical Society of Korea
    • /
    • v.38 no.6
    • /
    • pp.697-702
    • /
    • 2019
  • We propose a multi-band multi-scale DenseNet with dilated convolution that separates background music signals from broadcast content. Dilated convolution can learn the multi-scale context information represented by spectrogram. In computer simulation experiments, the proposed architecture is shown to improve Signal to Distortion Ratio (SDR) by 0.15 dB and 0.27 dB in 0dB and -10 dB Signal to Noise Ratio (SNR) environments, respectively.

A Transformer Protective Relaying Algorithm Using the Ratio of Induced Voltages (유기전압비를 이용한 변압기 보호계전 알고리즘)

  • Kang, Y.C.;Lee, B.E.
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.49 no.10
    • /
    • pp.524-530
    • /
    • 2000
  • This paper presents a transformer protective relaying algorithm using the ratio of induced voltages. The proposed algorithm calculates primary and secondary voltage from currents and voltages of primary and secondary windings. The ratio of primary and secondary induced voltages is equal to the turn ratio in case of the steady state and magnetic inrush. On the other hand, the ratio is different form the turn ratio in case of internal winding faults. The algorithm does not require B-H curve and can reduce the relay's operating time.

  • PDF

Molecular Analysis of Spontaneous Mutations in erm(A) and erm(C) Selected In vitro as a Constitutive MLS$_B$ Resistant Staphylococci (MLS$_B$계 항생물질 유도 내성 세균에서 In vitro로 선발된 지속성 내성형 erm(A)와 erm(C)의 분자적 특성 규명)

  • Yoon, Eun-Jeong;Jin, Sung-Hye;Choi, Eung-Chil;Shim, Mi-Ja
    • YAKHAK HOEJI
    • /
    • v.51 no.2
    • /
    • pp.108-114
    • /
    • 2007
  • The predominant Macrolides-Lincosamide-Streptogramin B (MLS$_B$) antibiotics resistance genes in staphylococci are erm(A) and erm(C). There is the phenomenon that the ratio of constitutively MLS$_B$ antibiotics resistance (cMLS) in erm(A) is much higher than in erm(C). Thus, we confirmed that the difference of the mutation ratio between erm(A) and erm(C) makes the phenomenon. We examined 8 staphylococci carrying inducibly expressed (iMLS) erm(A) or erm(C) genes. After overnight incubation in the presence of the non-inducer MLS$_B$ antibiotics, spontaneous mutants constitutively expressed MLS$_B$ resistance were selected. Against our expectation, the mutation ratio of erm(A) was lower than erm(C). Therefore, possibilities of other factors determining the ratio of cMLS phenotype might be concerned. All the mutants showed sequence alterations in translational attenuator and all the alterations seemed to give rise to change the second structure of mRNA to express constitutively. For erm(A), 4 different types of sequence deletions ranging from 72 bp to 122 bp and 3 different types of duplications ranging 24 bp to 93 bp were detected. Also, there were 9 different types of duplications ranging 15bp to 154bp in erm(C).

A Study on the Changes in Spatial Composition Ratio of National Rental Houses - Focused on the Jangseong-gun Jeollanam-do Province - (국민임대주택의 평면구성비 변화에 관한 연구 -전라남도 장성군을 중심으로 -)

  • Kim, Hong-Bae
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.20 no.1
    • /
    • pp.61-68
    • /
    • 2018
  • This study aims to investigate the changes in area ratios by space through floor plans of national leasing houses constructed by the LH in Jangseong-gun, particularly focusing on the floor plans of public leasing housing complexes built during the 1970s-80s and those during the 2010s. The results are as follows: First, according to the composition ratio of floor plans by period, the type of Bedroom> Livingroom> Common Area> Kitchen+Dining> Multi-purpose room> Bathroom> or the type of Bedroom> Livingroom> Kitchen/Dining> Common Area> Bathroom> Multi-purpose room were found to be high during the 1970s. Whereas, the type of Common Area>Living room(Kitchen/Dining included)>Bedroom>Bathroom>Front Entrance was found to be high during the 2010. It can be concluded that the ratio of Bedroom and Living room was found to be high during the 1970s, but after 2010s, the spacial composition ratio of Common Space, Living room, and Bedroom is getting higher in the order. Second, in terms of the composition ratio of floor plans by the area of unit household, among the floor plan of C-1, B-2, B-3, C-2 which were used since 2010s, the spatial ratio of Bedroom was maintained in the range of 20%; while during the 1970s, the Bedroom space of A-1(46%), A-2(46%), and A-3(41%) was found to be higher than 40%. It can be concluded that the size of bedroom space has doubled over time. In terms of the changes in the spatial ratio of Living room, A-1(15%), A-2(22%), and A-3(23%) were found during the 1970s. Compared to the recent floor plans of C-1(28%), B-2(25%), B-3(33%), and C-2(34%) which are applied in Jangseong-gun, Jeollanam-do province, no big changes have been found, particularly in the small floor plans (20% range).

Elastic settlements of identical angular footings in close proximity

  • R. Sarvesha;V. Srinivasan;Anjan Patelb
    • Geomechanics and Engineering
    • /
    • v.32 no.2
    • /
    • pp.193-207
    • /
    • 2023
  • In general, the numerous classical approaches available in the literature can anticipate the settlement of shallow foundations. As long as the footings are not in close proximity to other subsurface buildings, the findings achieved using these methods are legitimate and acceptable. However, due to increased urbanisation and land scarcity, footings are frequently built close together. As a result, these footings' settlement behaviour differs from those of isolated footings. A simpler approach for assessing the settlement behaviour of two square or rectangular footings placed in close proximity is presented in this work. A Parametric study has been carried out to examine the interference effect on the settlement of these footings placed in close vicinity on the surface of a homogeneous, isotropic and elastic soil medium. The interaction factors are examined by varying the different aspect ratios (L/B), clear spacing ratio (S/B) and intensity of loading on the right footing with respect to the left footing. Further, variation of the settlement ratio (δ/B) with respect to embedment depth ratio Df/B is examined. For square and rectangular footings, the interference settlement profile is also investigated by varying the clear spacing ratio (S/B) and the degree of loading. The results were compared to 3D finite element analysis and experimental data that were available.

A Study on A Mathematical Formulation of Protection Ratio and Its Calculation for Fixed Radio Relay System with Diversity (다이버시티를 갖는 고정 무선 중계 시스템에 대한 보호비의 수학적 표현과 계산에 대한 연구)

  • Suh Kyoung-Whoan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.17 no.4 s.107
    • /
    • pp.358-367
    • /
    • 2006
  • In this paper, a mathematical formulation of protection ratio and its calculation method are suggested for a radio relay system with diversity techniques. The analysis of protection ratio and its physical meaning have been performed for the space or frequency diversity system, and in particular protection ratios are reviewed in terms of the parameters of diversity improvement factor, which comprises antenna gain, separation distance between antennas, frequency and its difference between carriers, and distance. As one of simulated results, the co-channel protection ratio of 60 dB is obtained for the space diversity system regarding 6.2 GHz, 60 km, 64-QAM, and 25 m between antennas, which gives 15 dB less than the co-channel protection ratio of the non-space diversity system. In addition, the co-channel protection ratio for the frequency diversity system gives 64 dB in case of frequency offset of 0.5 GHz under the same conditions as the space diversity system, which brings about 11 dB less than the co-channel protection ratio of non-frequency diversity system. In consequency, it is interesting to note that the space diversity system is less sensitive to interference in comparison to the frequency diversity system and provides better quality of service for a given interference.