• Journal of the Korean Mathematical Society
• /
• v.58 no.4
• /
• pp.1035-1058
• /
• 2021

Under certain rather weak size conditions assumed on the kernels, some weighted norm inequalities for singular integral operators, related maximal operators, maximal truncated singular integral operators and Marcinkiewicz integral operators in nonisotropic setting will be shown. These weighted norm inequalities will enable us to obtain some vector valued inequalities for the above operators.

• Bulletin of the Korean Mathematical Society
• /
• v.35 no.3
• /
• pp.547-557
• /
• 1998

In this paper, we study submanifolds in the Euclidean space with parallel normal mean curvature vectorand special quadric representation. Especially we give a complete classification result relative to surfaces satisfying these conditions.

• Journal of the Korean Mathematical Society
• /
• v.33 no.2
• /
• pp.259-268
• /
• 1996

The Data Encryption Standard(DES) [3, 8, 9] was developed by an IBM team aroung 1974 and adopted as a national standard in 1977.

• Honam Mathematical Journal
• /
• v.36 no.4
• /
• pp.723-730
• /
• 2014

In the present paper, we introduce a type of Riemannian manifolds (namely, $W_4$-birecurrent manifold) and study the several properties of such a manifold on which some geometric conditions are imposed.

• The Pure and Applied Mathematics
• /
• v.6 no.1
• /
• pp.33-37
• /
• 1999

We obtain a generalization of Behera and Panda's result on nonlinear scalar case to the vector version.

• East Asian mathematical journal
• /
• v.17 no.2
• /
• pp.253-264
• /
• 2001

• Journal of Information Processing Systems
• /
• v.11 no.3
• /
• pp.354-369
• /
• 2015

Recently, there has been an increasing demand of high data rates services, where several multiuser multiple-input multiple-output (MU-MIMO) techniques were introduced to meet these demands. Among these techniques, vector perturbation combined with linear precoding techniques, such as zero-forcing and minimum mean-square error, have been proven to be efficient in reducing the transmit power and hence, perform close to the optimum algorithm. In this paper, we review several fixed-complexity vector perturbation techniques and investigate their performance under both perfect and imperfect channel knowledge at the transmitter. Also, we investigate the combination of block diagonalization with vector perturbation outline its merits.

• Research in Mathematical Education
• /
• v.4 no.2
• /
• pp.57-62
• /
• 2000

we motivate the of the velocity field of a fluid in three ways: from a calculation of the velocity of a rotating fluid relative to a coordinate system rotating with the fluid and from two calculations of a vector form of circulation in small circles or spheres suspended in a moving fluid.

• Journal of Information Processing Systems
• /
• v.16 no.5
• /
• pp.1158-1168
• /
• 2020

The distance vector-hop wireless sensor node location method is one of typical range-free location methods. In distance vector-hop location method, if a wireless node A can directly communicate with wireless sensor network nodes B and C at its communication range, the hop count from wireless sensor nodes A to B is considered to be the same as that form wireless sensor nodes A to C. However, the real distance between wireless sensor nodes A and B may be dissimilar to that between wireless sensor nodes A and C. Therefore, there may be a discrepancy between the real distance and the estimated hop count distance, and this will affect wireless sensor node location error of distance vector-hop method. To overcome this problem, it proposes a wireless sensor network node location method by modifying the method of distance estimation in the distance vector-hop method. Firstly, we set three different communication powers for each node. Different hop counts correspond to different communication powers; and so this makes the corresponding relationship between the real distance and hop count more accurate, and also reduces the distance error between the real and estimated distance in wireless sensor network. Secondly, distance difference between the estimated distance between wireless sensor network anchor nodes and their corresponding real distance is computed. The average value of distance errors that is computed in the second step is used to modify the estimated distance from the wireless sensor network anchor node to the unknown sensor node. The improved node location method has smaller node location error than the distance vector-hop algorithm and other improved location methods, which is proved by simulations.

• Communications of Mathematical Education
• /
• v.21 no.3
• /
• pp.515-525
• /
• 2007

In this study, we study on equations of bisector and trisectors of angle. We analyze various studies related with bisector and trisectors of angle. As a result we have known that trisectors of angle is able to received by paper folding method. Using some concepts of vector we have described equations of bisector and trisectors of angle.