An Optical and Infrared Photometric Study of the Young Open Cluster IC 1805 in the Giant H ii Region W4 ^†

Sung, Hwankyung,Bessell, Michael S.,Chun, Moo-Young,Yi, Jonghyuk,Nazé,, Y.,Lim, Beomdu,Karimov, R.,Rauw, G.,Park, Byeong-Gon,Hur, Hyeonoh American Astronomical Society 2017 The Astrophysical journal Supplement series Vol.230 No.1

<P>We present deep wide-field optical CCD photometry and mid-infrared Spitzer/IRAC and MIPS 24 mu m data for about 100,000 stars in the young open cluster IC 1805. The members of IC 1805 were selected from their location in the various color-color and color-magnitude diagrams, and the presence of H alpha emission, mid-infrared excess emission, and X-ray emission. The reddening law toward IC 1805 is nearly normal (R-V = 3.05 +/- 0.06). However, the distance modulus of the cluster is estimated to be 11.9 +/- 0.2 mag (d = 2.4 +/- 0.2 kpc) from the reddening-free color-magnitude diagrams, which is larger than the distance to the nearby massive star-forming region W3(OH) measured from the radio VLBA astrometry. We also determined the age of IC 1805 (tau(MSTO) = 3.5 Myr). In addition, we critically compared the age and mass scale from two pre-main-sequence evolution models. The initial mass function with a Salpeter-type slope of Gamma = -1.3 +/- 0.2 was obtained and the total mass of IC 1805 was estimated to be about 2700 +/- 200 M-circle dot. Finally, we found our distance determination to be statistically consistent with the Tycho-Gaia Astrometric Solution Data Release 1, within the errors. The proper motion of the B-type stars shows an elongated distribution along the Galactic plane, which could be explained by some of the B-type stars being formed in small clouds dispersed by previous episodes of star formation or supernova explosions.</P>

CCD PHOTOMETRY OF STANDARD STARS AT MAIDANAK ASTRONOMICAL OBSERVATORY IN UZBEKSTAN: TRANSFORMATIONS AND COMPARISONS

Lim, Beomdu,Sung, Hwan-Kyung,Bessell, M.S.,Karimov, R.,Ibrahimov, M. The Korean Astronomical Society 2009 Journal of The Korean Astronomical Society Vol.42 No.6

Observation of standard stars is of crucial importance in stellar photometry. We have studied the standard transformation relations of the UBV RI CCD photometric system at the Maidanak Astronomical Observatory in Uzbekistan. All observations were made with the AZT-22 1.5m telescope, SITe 2k CCD or Fairchild 486 CCD, and standard Bessell UBV RI filters from 2003 August to 2007 September. We observed many standard stars around the celestial equator observed by SAAO astronomers. The atmospheric extinction coefficients, photometric zero points, and time variation of photometric zero points of each night were determined. Secondary extinction coefficients and photometric zero points were very stable, while primary extinction coefficients showed a distinct seasonal variation. We also determined the transformation coefficients for each filter. For B, V, R, and I filters, the transformation to the SAAO standard system could be achieved with a straight line or a combination of two straight lines. However, in the case of the U filter and Fairchild 486 CCD combination, a significant non-linear correction term - related to the size of Balmer jump or the strength of the Balmer lines - of up to 0:08 mags was required. We found that our data matched well the SAAO photometry in V, B - V, V - I, and R - I. But in U - B, the difference in zero point was about 3.6 mmag and the scatter was about 0.02 mag. We attribute the relatively large scatter in U -B to the larger error in U of the SAAO photometry. We confirm the mostly small differences between the SAAO standard UBV RI system and the Landolt standard system. We also attempted to interpret the seasonal variation of the atmospheric extinction coefficients in the context of scattering sources in the earth's atmosphere.

세종 산개성단 탐사관측 (SOS) II. 중년 산개성단 NGC 2353의 UBVI CCD 측광

임범두,R. Karimov,M. Ibrahimov 한국천문학회 2010 天文學會報 Vol.35 No.2

Effective Model Of System Of Detection Of Intrusion For Computer Networks

M.M. Karimov,D.Ya.Irgasheva,K.A.Tashev,R.I. Rakhimov 대한전자공학회 2008 ICEIC:International Conference on Electronics, Inf Vol.1 No.1

In given article it is considered approaches of protection of the information for computer networks and multilevel model of detection and reflection of intrusions, protection against not authorized access to the information, providing creation of a hardware-software complex and the analysis of the traffic on the basis of complex application of new methods for computer networks.

Mathematical Planning for Revealing Optimal Synthetic Conditions of Naphthalene Chloromethylation

Pak, V.V.,Karimov, R.K.,Shakhidoyatov, Kh.M.,Yun, L.M.,Soh, D.W. The Speleological Society 2006 동굴 Vol.71 No.-

Chloromethylnaphthalene is a valuable compound for obtaining of the plant growing stimulator - -napthylacetic acid. Chloromethylation of naphthalene by paraformaldehyde in the presence of glacial acetic acid, phosphoric and hydrochloric acids at temperature 80 - 85C and duration - 6 hours the -chloromethylnaphthalene yield was 55-57%. Using Box-Wilson method for mathematical planning of experiment carried out optimization of its synthesis for purpose increasing -chloromethylnaphthalene yield. Preliminary, one - factor experiments were carried out for selecting independence main parameters influencing on the synthesis. A full factor experiment of 23 with extended matrix of planning was used for optimization. Aiming to increase the -chloromethylnaphthalene yield, the obtained mathematical model was used for program of sharp raising on the reply surface. The received optimal conditions for the -chloromethylnaphthalene synthesis were selected as following: molar ratio of naphthalene parapfsormaldehyde of 1 : 2 temperature - 105C duration of the reaction - 3 hours. The yield of -chloromethylnaphthalene under these optimal conditions was 75%.

Mathematical Planning for Revealing Optimal Synthetic Conditions of Naphthalene Choromethylation

( V. V. Pak ),( R. K. Karimov ),( Kh. M. Shakhidoyatov ),( L. M. Yun ),( D. W. Soh ) 한국동굴학회 2006 동굴 Vol.71 No.-

Chloromethylnaphthalene is a valuable compound for obtaining of the plant growing stimulato-napthylacetic acid. Chloromethylation of naphthalene by paraformaldehyde in the presence of glacial acetic acid, phosphoric and hydrochloric acids at temperature 80-85C and duration -6 hours the-chloromenthylnapnaphtalene yield was 55-57%. Using Box- Wilson method for mathematical planning of experiment carried out optimization of its synthesis for purpose increasing- chloromethylnaphthalene yield. Preliminary, one - factor experiments were carried out for selecting for selecting independence main parameters influencing on the synthesis. A full factor experiment of 23 with extended matrix of planning was used for optimization. Aiming to increase the-chloromethylnaphthalene yield, the obtained mathematical model was used for program of sharp raising on the reply surface. The received optimal conditions for the- chloromethylnaphthalene synthesis were selected as following: molar ratio of naphthalene-parapfsormaldehyde of 1 : 2 temperature-105C duration of the reaction - 3 hours. The yield of - chloromethylnaphthalene under these optimal conditions was 75%.

Process Optimization of Biphenile Chloromethylation

Pak, V.V.,Karimov, R.K.,Shakhidoyatov, Kh.M.,Soh, D.W. The Speleological Society 2006 동굴 Vol.73 No.-

Optimization of the biphenile chloromethylation process with paraphormaldegide has been done in the presence of $ZnCl_2$ with HCl gas by the Box-Wilson method of mathematical planning of experiment. The 4,4'-(dichloromethyl)-biphenile yield dependence on the piphenile -paraphormaldegide ratio, temperature and reaction duration has been studied. A mathematical model of the process has been developed and optimal conditions for the biphenile chloromethylation procedure has been determined.

Process Optimization of Biphenile Chloromethylation

( V. V. Pak ),( R. K. Karimov ),( Kh. M. Shakhidoyatov ),( D. W. Soh ) 한국동굴학회 2006 동굴 Vol.73 No.-

Optimization of the biphenile chloromethylation process with paraphormaldegide has been done in the presence of ZnCl2 with HCI gas by the Box-Wilson method of mathematical planning of experiment. The 4,4`-(dichloromethyl)-biphenile yield dependence on the biphenile-paraphormaldegide ratio, temperature and reaction duration has been studied. A mathematical model of the process has been developed and optimal conditions for the biphenile chloromethylation procedure has been determined.

우즈베키스탄 Maidanak 천문대 Fairchild 486 CCD의 기본적인 특성

Lim, Beom-Du,Sung, Hwan-Kyung,Karimov, R.,Ibrahimov, M. 한국천문학회 2008 天文學論叢 Vol.23 No.1

Understanding of the basic characteristics of an astronomical instrument is a prerequisite to obtaining reliable data from the instrument. We have analyzed more than 1,000 calibration images from the Fairchild 486 CCD (hereafter the Maidanak 4k CCD system) attached to the AZT-22 1.5m telescope at Maidanak Astronomical Observatory in Uzbekistan. The Maidanak 4k CCD system supports three readout modes through 1, 2, or 4 amplifiers. In most cases observers use 4-amplifier readout mode to save time. We have tested the stability and seasonal variation of zero levels and confirm that two quadrants of the images (Amp 1 & 2) show no appreciable seasonal variation. but the other two quadrants (Amp 3 & Amp 4) show an evident seasonal variation in the bias level. The Cryo Tiger, the cooling system used at the Maidanak 4k CCD system, maintains the CCD temperature at -108'E, and effectively suppresses the dark electrons. The mean value versus the variance plot of the flat images does not show the expected relation for an ideal Poisson noise distribution and this is attributed to the large variation in quantum efficiency between different pixels. In addition, we confirm that there is no appreciable difference in gain between readout amplifiers, but there is a large variation in quantum efficiency across CCD chip especially in U. Due to the finite length of shutter opening and closing time, the effective exposure time varies across the science images. We introduce two parameters to quantify the effect of this uneven illumination and present a method to remove these effects. We also present a method to remove the interference patterns appearing in the images obtained with longer wavelength filters and investigate the spatial variation of the point spread function.

늙은 산개성단 Berkeley 44의 UBVI CCD 측광 연구

임범두,성환경,Bessell, M.S.,Karimov, R.,Ibrahimov, M. 한국우주과학회 2009 한국우주과학회보 Vol.18 No.1