• Journal of Environmental Science International
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• v.19 no.7
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• pp.819-827
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• 2010

This study was conducted to investigate runoff characteristics of non-point pollutants source at the urban area in boeun area, Chungbuk Province. The monitoring site covering the watershed of $2.11\;km^2$ contains about 40.3 % of total watershed with the urban area. The monitoring was conducted with six events for five months and Event Mean Concentration(EMC) and Site Mean Concentration(SMC) of SS, BOD, CODMn, T-N, T-P were calculated on the result of the water quality parameters. As a result of the comparion between Arithmetic Mean Concentration and Event Mean Concentration, it showed that over all Event Mean Concentration was higher than Arithmetic Mean Concentration. And it showed that SS, BOD, T-P featured the first-flushing effect, showing relatively high concentration in early-stage storm event.

• 한국데이터정보과학회:학술대회논문집
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• 2003.10a
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• pp.229-238
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• 2003

K-means clustering has been widely used in many applications, such that pattern analysis, data analysis, market research and so on. It can identify dense and sparse regions among data attributes or object attributes. But k-means algorithm requires many hours to get k clusters, because it is more primitive and explorative. In this paper we propose a new method of k-means clustering using the grid-based representative value(arithmetic and trimmed mean) for sample. It is more fast than any traditional clustering method and maintains its accuracy.

• Kyungpook Mathematical Journal
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• v.53 no.3
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• pp.479-495
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• 2013

Taking the weighted geometric mean [11] on the cone of positive definite matrix, we propose an iterative mean algorithm involving weighted arithmetic and geometric means of $n$-positive definite matrices which is a weighted version of Carlson mean presented by Lee and Lim [13]. We show that each sequence of the weigthed Carlson iterative mean algorithm has a common limit and the common limit of satisfies weighted multidimensional versions of all properties like permutation symmetry, concavity, monotonicity, homogeneity, congruence invariancy, duality, mean inequalities.

• Communications of the Korean Mathematical Society
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• v.34 no.1
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• pp.239-251
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• 2019

In this paper we introduce a new formulation of symmetric homogeneous bivariate means that depends on the variation of a given continuous strictly increasing function on (0, ${\infty}$). It turns out that this class of means includes a lot of known bivariate means among them the arithmetic mean, the harmonic mean, the geometric mean, the logarithmic mean as well as the first and second Seiffert means. Using this new formulation we introduce a lot of new bivariate means and derive some mean-inequalities.

• Physical Therapy Korea
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• v.17 no.3
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• pp.20-30
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• 2010

This study examined whether any changes by mental task types on postural control in chronic stroke persons. Sixteen chronic stroke persons (mean age=53.75 yr) and sixteen age-and gender-matched healthy controls (mean age=54.44 yr) took part in this study. Participants randomly performed three different tasks on the stable and unstable surfaces. The no mental task was to stand while holding a 100 g weight in each hand, the arithmetic task (mental task) was to perform a silent 1-backwards counting while standing and holding a 100 g weight in each hand, and the simple task (mental task) was to stand and hold with both hands a tray (200 g) on which a glass filled with water has been placed. Sway path and sway velocity of the center of pressure (COP) were measured to assess standing postural control by task performance using the force platform. According to the results, in stroke group, total sway path and total sway velocity of COP was significantly decreased during arithmetic and simple task compared to no mental task on the stable surface (p<.05), and sway path (anteroposterior AP, mediolateral ML) of COP, total and sway velocity (AP, ML, total) of COP was significantly decreased during arithmetic and simple task compared to no mental task on the unstable surface (p<.05). Especially, sway path (AP, total) of COP and sway velocity (AP, ML, total) of COP was significantly decreased under the simple task when compared to the arithmetic task on the unstable surface (p<.05). In healthy control group, sway path (AP, ML, total) of COP and sway velocity (AP, ML, total) of COP was significantly decreased during arithmetic and simple task compared to no mental task on the stable and unstable surface (p<.05), and sway path (AP, total) of COP and sway velocity (AP, ML, total) of COP was significantly decreased under the simple task when compared to the arithmetic task on the unstable surface (p<.05). In conclusion, the findings of this study showed that arithmetic and simple task improved standing postural control for chronic stroke patients and the type of arithmetic and simple tasks were critical factor that reduced standing postural sway in dual-task conditions. Future research should determine whether dual-task conditions, including simple task, would be effective as a training program for standing postural control of stroke patients.

• Kyungpook Mathematical Journal
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• v.14 no.2
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• pp.165-170
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• 1974

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.218-220
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• 2004

Orthogonal frequency division multiplexing(OFDM) is one of the most promising technique for next generation wireless broadband communication systems. In this paper, we propose a new bit allocation algorithm in multiuser OFDM. The proposed algorithm is derived from the geometric progression of the additional transmit power of subcarriers and the arithmetic-geometric means inequality. The simulation shows that this algorithm has similar performance to the conventional adaptive bit allocation algorithm and lower computational complexity than the existing algorithms.

• Kyungpook Mathematical Journal
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• v.47 no.4
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• pp.595-600
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• 2007

In this paper we consider weighted arithmetic and geometric means of several positive definite operators proposed by Sagae and Tanabe and we establish a reverse inequality of the arithmetic and geometric means via Specht ratio and the Thompson metric on the convex cone of positive definite operators.

• The Pure and Applied Mathematics
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• v.19 no.3
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• pp.305-313
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• 2012

In this note we study Nesbitt's Inequality and modify it to make several inequalities. We prove some inequalities by using power series and Cauchy-Schwarz Inequality.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.534-537
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• 1999

This paper describes a design of pipelined adaptive decision-feedback equalizer (PADFE) for high bit-rate wireless digital communication systems. To enhance the throughput rate of ADFE, two pipeline stages are inserted into the critical path of ADFE by using delayed least-mean-square (DLMS) algorithm. Redundant binary (RB) arithmetic is applied to all the data processing of ADFE including filter laps and coefficient update blocks. When compared with conventional methods based on two's complement arithmetic, the proposed approach reduces arithmetic complexity, as well as results in a very simple complex-valued filter structure, thus suitable for VLSI implementation. The design parameters (filter tap, coefficient and internal bit-width, etc.) and equalization performance (bit error rate, convergence speed, etc.) are analyzed by algorithm-level simulation using COSSAP. The PADFE was designed using VHDL and Synopsys, and mapped into two ALTERA FLEX10k100 FPGAs.