• Journal of The Korean Astronomical Society
• /
• v.29 no.spc1
• /
• pp.325-326
• /
• 1996

We present the Programme of Monitoring of Flare Stars in the Orion aggregate by. CCD based. Photometer mounted at the Newtonian focus of 70/98/210-cm meniscus telescope through glass imaging quality C1 filter (3900${\AA}$/800${\AA}$) with a time resolution of 0.5-1.0 min.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.3
• /
• pp.397-399
• /
• 2003

• Archives of Pharmacal Research
• /
• v.20 no.6
• /
• pp.602-609
• /
• 1997

A new series of 1, 3, 4-oxadiazoles, 1, 3, 4-thiadiazoles and 1, 2, 4-triazoles incorporated directly and/or indirectly into a xanthenone moiety at position-2-were synthesized. Some of the newly prepared compounds were biologically tested as schistosomicides in experimental animals.

• Advances in concrete construction
• /
• v.10 no.6
• /
• pp.537-546
• /
• 2020

Exterior walls in buildings are exposed to various forms of thermal loads, which depend on the positions of walls. Therefore, one of the efficient methods for improving the energy competence of buildings is improving the thermal properties of insulation plaster mortar. In this study, lightweight fine aggregate (LWFA) and micro rubber ash (MRA) from recycled tires were used as partial replacements for sand. The flow ability, unit weight, compressive strength, tensile strength, thermal conductivity (K-value), drying shrinkage and microstructure scan of lightweight rubberized mortar (LWRM) were investigated. Ten mixtures of LWRM were prepared as follows: traditional cement mortar (control mixture); three mixes with different percentages of LWFA (25%, 50% and 75%); three mixes with different percentages of MRA (2.5%, 5% and 7.5%); and three mixes consisting both types with determined ratios (25% LWFA+5% MRA, 50% LWFA+5% MRA and 75% LWFA+5% MRA). The flow ability of the mortars was 22±2 cm, and LWRM contained LWFA and MRA. The compressive and tensile strength decreased by approximately 64% and 57%, respectively, when 75% LWFA was used compared with those when the control mix was used. The compressive and tensile strength decreased when 5% MRA was used. By contrast, mixes with determined ratios of LWFA and MRA affected reduced unit weight, K-value and dry shrinkage.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.9
• /
• pp.2807-2810
• /
• 2013

• Communications of the Korean Mathematical Society
• /
• v.35 no.3
• /
• pp.711-722
• /
• 2020

Given a semigroup S generated by its squares equipped with an involutive automorphism 𝝈 and a multiplicative function 𝜇 : S → ℂ such that 𝜇(x𝜎(x)) = 1 for all x ∈ S, we determine the complex-valued solutions of the following functional equations f(xy) + 𝜇(y)f(𝜎(y)x) = 2f(x)g(y), x, y ∈ S and f(xy) + 𝜇(y)f(𝜎(y)x) = 2f(y)g(x), x, y ∈ S.

• Kyungpook Mathematical Journal
• /
• v.51 no.3
• /
• pp.251-260
• /
• 2011

The aim of this paper is to obtain a solution of a certain multidimensional convolution integral equation of Fredholm type whose kernel involves a generalized polynomial set. A number of results follow as special cases from the main theorem by specifying the parameters of the generalized polynomial set.

• ETRI Journal
• /
• v.28 no.2
• /
• pp.250-252
• /
• 2006

In this letter, a discrete state, discrete time chaotic pseudo random number generator (CPRNG) is presented for stream ciphering of text, audio, or image data. The CPRNG is treated as a finite state machine, and its state is modulated according to the input bit sequence of the signal to be encrypted. The modulated state sequence obtained can be transmitted as a spread spectrum or encrypted data.

• Journal of the Korean Mathematical Society
• /
• v.53 no.5
• /
• pp.969-990
• /
• 2016

We derive a sampling theorem associated with first order self-adjoint eigenvalue problem with a finite rank perturbation. The class of the sampled integral transforms is of finite Fourier type where the kernel has an additional perturbation.

• Archives of Pharmacal Research
• /
• v.20 no.6
• /
• pp.610-619
• /
• 1997

Some new 9H-thioxanthen-9-one incorporated into heterocyclic systems such as pyridone 8, pyrazoline 9, pyranone 11, iminopyrane 12, furopyrimidine 17, imidazothiazole 19, thiazole 21, triazine 24 and other related compounds through a para imminophenyl grouping at position-1 of the thioxanthenone ring were synthesized and tested as antitumor agents against L1210 leukemia in mice. Some of the new compounds showed considerable antitumor activity.