ITE Technical Report
Online ISSN : 2424-1970
Print ISSN : 1342-6893
ISSN-L : 1342-6893
23.1
Showing 1-33 articles out of 33 articles from the selected issue
  • Type: Cover
    Pages Cover1-
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Type: Index
    Pages Toc1-
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • H. Kominami, T. Aoki, Y. Nakanishi, Y. Hatanaka
    Type: Article
    Session ID: IDY99-1
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The surface potential of ZnS : Ag, Cl phosphor coated with In_2O_3 conducting layer under low energy electron excitation was investigated. The mesh electrode was fabricated on the phosphor sample, then, mesh and sample currents were measured a s a function of mesh voltage. The mesh and sample currents changed abruptly at mesh voltage corresponding to the surface potential. The surface potential changed according with the weight of In[OCH(CH_3)_2]_3. It is suggested that the pronounced charging-up occurs at the excitation voltage lower than 200V in ZnS : Ag, Cl phosphor. It should be emphasized that this method was very effective for the measurement of surface potential. Moreover, the incident electron energy was increased with respect to the coating ratio. It indicated that the resistivity of the phosphor surface decreased by the coating process.
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  • H. Nakajima, H. Kominami, T. Aoki, Y. Nakanishi, Y. Hatanaka
    Type: Article
    Session ID: IDY99-2
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Preparation of SrGa_2S_4 : Ce thin films showing blue-emission with good chromaticity has been carries out by the multi-source deposition technique, then the structural and luminescent properties of the films were characterized. I this experiment, the dependence of the properties on Ga_2S_3/Sr flux ratio and annealing conditions was investigated. The film prepared at CeCl_3/Sr and Ga_2S_3/Sr flux ratios of 0.03 and 60, respectively, and annealed at 850℃ in Ar showed a luminance of about 1000cd/cm^2 and CIE coordinates of (0.11, 0.098).
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  • K. Horikawa, M. Kottaisamy, H. Kominami, T. Aoki, N. Azuma, T. Nakamur ...
    Type: Article
    Session ID: IDY99-3
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Red emitting SrTiO_3 : Pr, Al phosphors were synthesized by sol-gel method, the effect of Al on the luminescent properties of the phosphors were investigated. CL luminance and chromaticity of the red emission were improved with increasing Al contents up to 30mol%. The phosphor with a Al content of 30mol% showed 33cd/m^2 under excitation at 2kV and 108μA/cm^2. It was found from the measurements of SEM and NMR that almost of Al is distributed homogeneously as Al_2O_3 on the phosphor surface. Moreover, it was suggested from the measurements of XRD and NMR that new formation of tetrahedral Al-O bond might be concerned with the emission.
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  • M. Kottaisamy, M. Mohan Rao, D. Jeyakumar, T. Aoki, Y. Nakanishi, Y. H ...
    Type: Article
    Session ID: IDY99-4
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Homogeneously europium doped yttrium oxide and oxysulfide has been prepared from its nitrates directly using fuels like urea-ODH (oxalyldihydrazide) and thiourea respectively, employing self-propagating high temperature synthesis techniques. The material synthesized has been characterized by powder X-ray diffraction, photoluminescent emission spectroscopy. The results indicate that the phase pure europium doped yttrium oxide and oxy sulfide can be obtained at very low temperature in the range of 250-500℃ in short time. The as formed products were sintered with and without flux (alkali fluorides). PL intensity of the phosphor with the flux was higher than that of the phosphor without the flux.
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  • K. Kaiya, N. Takahashi, T. Matsuzawa, T. Nakamura
    Type: Article
    Session ID: IDY99-5
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    EPR spectroscopy has been applied to investigate the europium(II) sites in europium(II)-doped aluminate phosphors with tridymite structure. X-band spectra of the phosphors are quite complicated to analyse due to large zero-field splittings, so that little information about europium(II) ions can be obtained. On the contrary, high-frequency EPR measured at 90 or 180 GHz shows symmetric spectra centred around about g=2.0. The spectral simulation confirmed there that is one site in the CaAl_2O_4, three in the SrAl_2O_4 and two in the BaAl_2O_4 in contrast to our expectations from crystallographic sites.
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  • Naoyuki TAKAHASHI, Kazuhiko KAIYA, Kouji OMICHI, Takato NAKAMURA, Yosh ...
    Type: Article
    Session ID: IDY99-6
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Zinc oxide (ZnO) films were deposited on sapphire (000l) substrates by halide vapor phase epitaxy (VPE) using ZnCl_2 as a chloride source. Growth rate of the ZnO film increased with increasing growth temperature. The maximum growth rate was about 3μm/h at 950℃ The X-ray diffractogram showed a typical pattern of epitaxially grown ZnO with a hexagonal structure, and a full width at half-maximum (FWHM) of 23.3 minutes was obtained in the X-ray diffraction profile. A strong band edge emission at 370.0 nm was observed at 20K photoluminescence spectra.
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  • Aki Miyake, Hiroko Kominami, Toru Aoki, Hirokazu Tatsuoka, Hiroshi Kuw ...
    Type: Article
    Session ID: IDY99-7
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The dependence of the structural, photoluminescent and cathodoluminescent properties of ZnO thin films deposited by electron beam evaporation on the preparation conditions has been investigated. The films deposited at 200℃ to 400℃ showed c-axis orientation. The films showed two kind of emission with peaks at around 5l0nm or 540nm depending on the temperature and atomosphere at annealing. The film annealed at 800℃ in air showed CL luminance of about 60cd/m^2 under excitation with 2kV, 400μA/cm^2. Moreover, it showed CL without charging-up under excitation even at 250V.
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  • Shucheng CHU, Tetsuhiro SAISHO, Shingo SAKAKIBARA, Fumiyasu TANOUE, Ka ...
    Type: Article
    Session ID: IDY99-8
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    High quality InGaN/GaN single heterostructures were prepared by using a simple mixed sources (Ga and In metal) method in a hot wall epitaxy (HWE) system. Strong near band edge emission peaks ranging from 370 to 465 nm in room temperature PL spectra and X-rays rocking curve FWHM of InGaN (0002) as narrow as 7.3 arcmin were obtained. Few additional dislocations were produced at the interface of InGaN/GaN or during the growth of InGanN. In incorporation can be controlled independently by the substrate temperature, N_2 partial pressure, and the mixed source temperature, respectively.
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  • T. Aoki, H. Yamamoto, Y. Aoki, Y. Nakanishi, Y. Hatanaka
    Type: Article
    Session ID: IDY99-9
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    High Concentration p-type doping of ZnSe was carried out by dopant diffusion using excimer laser radiation. The Na doped p-type ZnSe was formed by excimer laser pulse to the sample surface after deposition of Na_2Se for dopant source on ZnSe surface. We have reported that low resistivity ZnSe layer (holl concentration : 5×10^<19>cm^<-3> mobility : 8.1cmV^<-1>S^<-1>) and ohmic contact between Na doped ZnSe and gold electrode were obtained by laser doping with 550℃, 10min of thermal annealing in a furnace. The Na doping was also observed without thermal annealing and the ZnSe diode prepared by this method could be injected about 80Acm-2 of current. It was found that 1500K of temperature increment at sample surface by excimer laser radiation from result of computer simulation.
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  • T. Muramatsu, Y. Xu, T. Aoki, Y. Hatanaka
    Type: Article
    Session ID: IDY99-10
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    SiC thin films were deposited by plasma CVD and remote plasma CVD method using hexamethyledisilane. It was found that the adhesibility of SiC thin film on the plastic substrate increases with the surface energy of the substrate which, in turn, can be increased by the Oxygen plasma treatment. Deposition rate was higher for the films deposited at room temperature using 50W rf power in plasma CVD method with a pressure of 1.0 Torr. The deposited films were useful for rejecting UV radiation.
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  • Eiichirou Uda, Osamu Nakamura, Sadao Matsumoto, Toshiharu Higuchi
    Type: Article
    Session ID: IDY99-11
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We investigated top-layer scandate cathodes, which are the most promising of scandate cathodes. Among the cathodes which we prepared with a layer of various thickness, the best pulse emission of 80A/cm^2 at 1300K was recorded with cathodes having a top-layer consisting of a Sc_2O_3 layer 2nm thick on a W layer 8nm thick. The emission variation of these cathodes was evaluated in life tests. The life characteristics were good in both diode and triode evaluation. We also determined diffusion coefficients of W and Sc_2O_3 with unporous W pellets covered with Sc_2O_3 and W layer. Variation of surface concentrations of these pellets during life tests were measured using Auger electron spectroscopy. The diffusion coefficients were 6.4×10^<-19> 1.0×10^<-18> and 1.6×10^<-18>cm^2/s at 1220K, 1300K, and 1370K, respectively. Detailed observation of Auger spectra suggests unchanged chemical states of O, Sc, and W during diffusion process.
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  • S. Taguchi, M. Shibata, Y. Suzuki, S. Sasaki, Y. Nonaka, T. Aida
    Type: Article
    Session ID: IDY99-12
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    An S-type impregnated cathode depends on the Ba consumption for its life time, whereas an M-type the composition change of the coating film as well as the Ba consumption. For the latter cathode, the factor which ends the cathode life is determined by the cathode operation temperature. The lifetime determination factor for an M-type cathode, operating at 1000℃, is the Ba consumption rate. Activation energy of Ba evaporation process undergoes three stages during the cathode life. In the first stage, the energy increases from early 〜3eV to 〜4eV. Second stage is a stable period maintaining the activation energy of 〜4eV. Finally the energy rapidly increases and the cathode life comes to an end.
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  • Toshiaki Kusunoki, Mutsumi Suzuki, Masakazu Sagawa, Makoto Okai, Yoshi ...
    Type: Article
    Session ID: IDY99-13
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    An MIM-cathode array is fabricated by photolithography and its color display operation is demonstrated. Surface cleaning with UV-ozone ashing keeps the transfer ratio at 0.2%, which is about the same as that of an MIM-cathode made by the metal-mask method. By combining the MIM-cathode with conventional CRT phosphors (P22), we obtained white luminous efficiency of 8lm/W for the screen at an accelerating voltage, Va=4kV. We also developed a frit-sealed display panel with the MIM-cathode array.
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  • K. Ozawa, K. Tokunaga, S. Kanemaru, T. Matsukawa, J. Itoh
    Type: Article
    Session ID: IDY99-14
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    A new Si field emitter tip with metal-oxide-semiconductor field-effect-transistor (MOSFET) structure was fabricated and demonstrated. In the present device, a well-sharpened Si tip was made junst on the drain of the MOSFET and two gates were made of poly-Si layer between the drain and the source. Among the gates, the one having an aperture surrounding the tip was mainly used as an extraction electrode and the other was used as an FET gate. By employing the poly-Si gates, the fabrication process was optimized especially in the activation temperature after ion implantation doping and consequently, the MOSFET characteristics was much improved. The fabrication process and emission characteristics are described in detail.
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  • Chizuka Tani
    Type: Article
    Session ID: IDY99-15
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    High presence & reality dispalys and electronic-paper displays are expected as the big next-generation dispalys in the second phase of multimedia age. The object and classification of the high presence & reality displays and the present development trends of the main technologies such as a super wide viewing angle display, a 3D display and a surround screen display are described. The visual fatigue problems and future realization prospects are also discussed.
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  • N. Kosugi, Y. Ito, K. Wani, L.F. Weber
    Type: Article
    Session ID: IDY99-16
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Back ground emission of AC-PDP deteriorates picture quality such as contrast ratio. Back ground emission occurs at a set-up period in which all pixels are activated to form initial wall voltage. Wall voltage input-output (WVIO) curve was studied for color AC-PDP to optimize a set-up waveform for low back ground emission. It was found that a ramp waveform slower than 7.5V/us reduces the back ground emission to the level of less than 10% of the conventional waveform. A42" panel with contrast ratio of 550 : 1 was commercialized using the ramp waveform.
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  • Shigeki Harada, Akihiko Iwata
    Type: Article
    Session ID: IDY99-17
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The relationship between the luminous efficiency and the location of the bus electrodes on the transparent electrodes was investigated with a view to optimizing the geometric structure of AC-PDPs. As a result, it was found that the bus electrodes should be located at the far side from the discharge gap. Furthermore, the new structure in which the bus electrodes was separated from the transparent electrodes in order to control surface discharge area was proposed. As a result, more than a 22% higher efficiency is obtained in this new structure when compared with the conventional structure.
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  • Takashi Hashimoto, Akihiko Iwata
    Type: Article
    Session ID: IDY99-18
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper describes a novel waveform which improved the luminous efficiency of AC-PDP without reducing the voltage margin. This waveform, which induces self-erase discharges by space charges, utilizes the memory effect of space charges like the pulse memory of DC-PDP, in addition to the memory effect of wall charges. More than a 15% higher efficiency is obtained in the 40-inch diagonal XGA AC-PDP developed by us when compared with the conventional waveform at the same operating point.
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  • Y. Torisaki, M. Nozu, K. Amemiya, M. Ebe
    Type: Article
    Session ID: IDY99-19
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    "T"-shaped electrodes divided in each discharge cell were designed for high luminance efficiency and high definition Co-planner type AC-PDPs. A 1.2lm/W of luminance efficiency for 40inch -VGA panel and a 1.0lm/W for 50inch-XGA wide panel were realized with this electrodes. In our discharge cell structure, 0.03mm of maximum tolerance for panel assembling process was needed, and accomplished for manufacturing process.
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  • Toshihiro Yoshioka, Laurent Tessier, Akifumi Okigawa, Kaoru Toki
    Type: Article
    Session ID: IDY99-20
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In order to determine the basic processes in an AC-PDP micro-cell discharge, the spatio-temporal characterization of different emission lines has been measured. Multiple lines from XeI, HeI and XeII were detected in He-Xe gas mixtures of various gas pressure and composition. The results show some strong correlation between the different emission lines above cathode and a possible explanation of the kinetics involved is proposed. The data issued from this set of measurements might stand for a very useful tool of PDP discharge modeling.
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  • Koichi HAMADA, Toshihiro YAMAMOTO, Taiichiro KURITA, Yoshimichi TAKANO ...
    Type: Article
    Session ID: IDY99-21
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We have studied a field-sequential stereoscopic display system with 42-inch HDTV PDP and confirmed that a field-sequential stereoscopic image can be displayed with currently available PDP panels. But in our experiments, we found that the cross-talk impairment between left and right images is more visible for a PDP display than a CRT display. We investigated the cause of the cross-talk and concluded that it is mainly caused by the decay time of phosphor emission of the PDPs. We estimate the amount of cross-talk from the decay time of phosphor and compare it with the measured values. We also propose a method to reduce the cross-talk by signal processing.
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  • Yoshifumi Amano, Joichi Endo, Bala K. Velayudhan
    Type: Article
    Session ID: IDY99-22
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Even though the surface discharge PDP (SD PDP) has become a standard form of PDP, there is no doubt that we need another breakthrough to achieve less cost and more efficiency. The historical approach of a vertical discharge PDP (VD PDP) has some advantages comparingwith a SD PDP, but its life problem caused by ion bombardment to the phosphor layer seems to be a fatal problem for a VD PDP. A new driving method described here will make it possible tosolve this issue and give a bright view for the second generation PDP based on a VD PDP.
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  • Takahiro Senda, Hideyuki Takakura, Yoshihiro Hamakawa
    Type: Article
    Session ID: IDY99-23
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    A series of systematic investigation has been made on a new type of full color display devices combined ultra-violet thin film EL devices with visible light phosphors. We have optimized cell design parameters, and developed new structure of UV EL/PL hybrid device. Technical data on fabrication of the UV EL device together with R.G.B. visible light PL layers are presented. The maximum luminance of 50cd/m^2(R), 30cd/m^2(G) and l0cd/m^2(B) have been archieved.
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  • Mizumoto USHIROZAWA, Yoshimichi TAKANO
    Type: Article
    Session ID: IDY99-24
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Conduction mechanism is necessary so that Y_2O_3 which is an insulator may work as a cathode of DC-PDP. In order to clarify the mechanism thin film Y_2O_3/Al structure cathodes are examined. As the result, it seemed to prove the fact next. Many cracks are formed in Y_2O_3 by the high-temperature process. From the crack, Al cathode bus line is sputtered in aging. The Y_2O_3 surface is covered thinly with this Al and a conduction path is formed. In the meantime, the crack causes the sputter of the cathode bus line, and it becomes a short life. When Ni is used as a cathode bus line there are the smaller cracks in Y_2O_3 films and the cathode has a longer life than Al.
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  • Y. Agawa, Y. Yamamoto, S. Amano, N. Sasaki, J. Yuyama
    Type: Article
    Session ID: IDY99-25
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We are developing a system which measures the secondary electron yield (γ-value) of MgO films. The γ -value is determined by measuring the secondary electron current ejected from the sample irradiated by a mass analyzed ion beam of 50〜1000 eV. To improve the S/N ratio the system is designed to suppress electrons generated in the beam transport and to keep the vacuum pressure lower than 10^<-7>Pa. Prior to the construction of this system, we measure γ-values of W and MgO films by Xe ion beam irradiation using an existing low energy ion beam facility. Two kinds of MgO samples were evaporated on stainless steel with different orientations. The obtained γ-value for W is constant over the energy range from 100 to 1000 eV and about 0.02. The γ-value for MgO film showed energy dependence and difference with orientation.
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  • A. Shiokawa, Y. Takada, R. Murai, H. Tanaka
    Type: Article
    Session ID: IDY99-26
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The research and the development on a MgO film characteristics is very important for the development of recent AC-type Plasma Display Panels (PDPs). A γ coefficient is one of the MgO film characteristic which correlates to the ignition voltage or the luminous efficiency of PDPs. In this paper, we propose a new technique for γ coefficient evaluation on the MgO films using the pin-shaped electrode discharge for ion generation. And we describe the experimental results which include the correlation between the ignition voltage and the measured γ coefficient values, difference of the γ coefficient values by gas species or sample treatment before the measurement.
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  • Tomoko Suzuki, Akira Kaneko, Yoshio Watanabe, Nobuaki Furuya
    Type: Article
    Session ID: IDY99-27
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We have developed the novel measurement technique of the secondary electron emission coefficient by using gas breakdown with CO_2 laser. We measured the MgO/Pt ratio and charge value of Pt electrode with various pure gases and mixed gas. Also, we made clear the influence of air exposure on MgO films.
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  • Manabu Ishimoto, Souichiro Hidaka, Keiichi Betsui, Tutae Shinoda
    Type: Article
    Session ID: IDY99-28
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We successfully measured the secondary electron emission yield (γ) of MgO thin films for protecting layer of AC-PDP. We made the measurement apparatus with which we could measure the γ in high stability. The variation of repeating measurement and the long-time (1 hour) measurement were within 5%. With this apparatus, we measured the heat treatment effect on γ, and the relationship between γ and the acceleration voltage of induced ion. And we also measured the energy distribution of secondary electrons from metal (copper) and MgO to investigate the electron emission process. We investigated the difference of the distribution between the metal and non-conductive material, and we discuss the surface charge effect on the distribution.
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  • K. Yoshida, H. Lin, H. Uchiike, M. Sawa
    Type: Article
    Session ID: IDY99-29
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    MgO is now applied to protective material for PDP because it have large value of secondary electron emission yield, r_i, and strong properties for sputtering. In order to improve luminance and luminous efficiency for PDP, it is necessary to research the possibility of transmissive-material-to-ultraviolet-rays to protecting layer. In our laboratory, secondary electron emission characteristics by ion bombardment have been investigated and it have measured.
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  • Yutaka Hotta, Makiko Hayashi, Sumihito Sago, Tomoaki Nakamura, Wataru ...
    Type: Article
    Session ID: IDY99-30
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In order to reduce the cost of AC-PDP, we studied tne fabrication process of the protective layer for AC-PDP by chemical solution deposition method. A stable MgO precursor solution was prepared from Mg-metal, 2-methoxyethanol, alcohol and organic additives. A MgO layer was prepared by spin coating using the precursor solution and firing at 500℃ in air. The MgO layer showed (111) plane orientation and high transmission coefficient (>95%). The measurement of discharge properties indicated that our MgO layer had the similar performance compared with electron beam evaporated one.
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  • Type: Appendix
    Pages App1-
    Published: January 21, 1999
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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