• School Mathematics
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• v.3 no.2
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• pp.281-294
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• 2001

As a measure of the center of data, arithmetical mean, median, mode, harmonic mean and geometric mean are generally used. Students must learn qualitative aspect of average values as well as its calculation for its adequate use. As the result of the learning, they should be able to select the appropriate average value according to the characteristic of data and problem context. For this object, the historical origin and visual interpretation of average values were introduced in this paper. And to help teaching several meanings of average values, several examples including context were suggested.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.394-397
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• 2004

Working-day calculation with weather factors of construction-site has estimated wethout proper data. They usually estimate it with their own experience and intuition. It causes not only economic loss to time-adjustment but also conflict with each participants. Moreover, weather estimation becomes worse than before, due to tendency of recently weather change. So, in this paper we present optimal estimation method as assessment by period of the arithmetical mean methods. For that, we analyse characteristic of the regions and weather change of temperature and rainfall which affects time.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.56-60
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• 2007

Nowadays shear wall structural system is gradually changing to framed structure. For this reason, lightweight panel is increasingly being used as separating walls. One of design methods to obtain high transmission loss is double panel. To predict the acoustic performance of double panel, prediction of transmission loss of single panel must be performed, previously. In this study, the predicted values for four single panels were compared with the measured values. The result shows the arithmetical average deviations(100Hz to 3150Hz) between the predicted and measured transmission loss were in range between 1.1dB and 3.9dB. The predicted values were generally lower than measured values above critical frequency. The single-number quantities, $R_W+C$, were predicted in range between 36dB to 38dB, and the differences of single-number quantities between the predicted and measured value were within 1dB.

• Journal of the Korean Society for Precision Engineering
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• v.9 no.4
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• pp.72-77
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• 1992

In this study, using in-process tool failure detecting system by AE method in turning machining, we measured AE signal from the tool, and the surface roughness of workpiece and then compared it with tool wear. As a result, we found that tool failure can be predicted by means of surface roughness of the workpiece and it can be predicted more precisely by the arithmetical average roughness (Ra) than by the maximum height of irregularities (Rmax) of the workpiece. Also, we found that we could judge whether it was sudden failure or the wear by means of the shape of AE signal and the range distri- bution of power spectrum frequency when tool danage was happened.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.4
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• pp.7-13
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• 2005

Many domestic studies related to service quality are performed but the study on computing Service Quality Score is not yet activated. Because Service quality measurement plays an important role in assessing service performance and diagnosing service problems, it is very important that service quality is measured exactly. Therefore this study offered realistic approach method for computing Service Quality Score by using T.L. Saaty's Analytic Hierarchy Process technique. That is, Service Quality Score of this study is computed by using customer's priority(weights) for five dimensions(Tangible, Reliability, Assurance, Responsiveness, Empathy). This method is more realistic than the existing method computed by an arithmetical average of dimension's variables.

• The Mathematical Education
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• v.51 no.4
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• pp.377-393
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• 2012

The understanding demands the different degree of the understanding according to student's learning situation. In this paper, we investigate what is the foundation for the complete understanding for the generalization in the generalization-process and justification of some concepts or some theories, through a case. We discovered that the completeness of the understanding in the generalization-process and justification requires 'the meaningful-mental object' which can give the meaning about the concept or theory to students. Students can do the generalization-process through the construction of 'the meaningful-mental object' and confirm the validity of generalization through 'the meaningful-mental object' which is constructed by them. And we can judge the whether students construct the completeness of the understanding or not, by 'the meaningful-mental object' of the student. Hence 'the meaningful-mental object' are vital condition for the generalization-process and justification.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.60-67
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• 2012

In the study, the effect grinding condition on the workpiece arithmetical average roughness(Ra) to 10 steps leading to cutting each section with the spindle rotational speed 8000rpm and feed rate 150mm/min of grinding in GC(green silicon carbide) grinding processing after heat treatment and non heat treatment of SCM415 material. Also the following conclusions were obtained analysis of stress distribution displacement and finite elements method(FEM) on assemble parts with 3+2 axis simultaneous control through grinding and gave a load 11kg on ATC arm both sides gave a load of 11kg. For the centerline average roughness(Ra) in the heat and non-heat treatment work pieces, which were appeared the most favorable in the fifth section were $0.511{\mu}m$ and $0.514{\mu}m$, that were shown in the near the straight line section was the smallest deformation of curve. In addition, the bad surface roughness appeared on the path is too long by changing angle, the more inclined depth of cut, because the chip discharging is not smoothly.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.835-845
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• 1994

In this paper, the effects of the adhesive thickness and adherend roughness on the static and fatigue strengths of the adhesively bonded circular single lap joints has been investigated by an experimental method. The stacking sequence effect of the composite adherend on the static and fatigue strength and the fracture patterns of the adhesive failure were also observed. Since the circular single lap joint fails catastrophically beyond the static strength of fatigue limit, the tubular polygonal adhesively bonded joints such as triangular, tetragonal, pentagonal, hexagonal as well as elliptical joints were manufactured in order to give partial mechanical characteristics to the adhesively bonded tubular joints. These joints were tested both in static and fatigue modes. From the experimental investigations, it was found that the fatigue strength of the circular adhesively bonded joints was much dependent on the arithmetical average surface roughness of the adherends and the polygonal adhesively bonded joints had better fatigue strength characteristics than the circular adhesively bonded joints.

• Journal of radiological science and technology
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• v.20 no.1
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• pp.51-54
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• 1997

This study is to evaluate the individual angulation on maxlliary sinus projection and establishing angulation in children by new geometrical method. There were two groups, which are 60 cases in children (ranged from 1yr to 3yrs, 3yrs to 8yrs, 8yrs to 12yrs) and 50 cases in adults. We analyzed the true lateral maxillary sinus film of total 110 patients using new geometrical method. We demonstrated an angle of maxillary sinus projection. Arithmetical average angulation in adults is 36.56 degrees that accord with Waters. Whereas it is not valid during development of facial bone in childhood. The individual range of angulation according to age was that 1yr to 3yrs is 50-47 degrees, 3yrs to 8yrs is 47-40 degrees, 8yrs to 12yrs is 40-38 degrees. This geomatrical method will be useful in establishing angulation for maxillary sinus profection.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.367-375
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• 2016

In the present study, we conducted genetic characterization of 90 commercial maize varieties and parental lines using microsatellite markers. Thirteen microsatellite markers were selected from 100 primer pairs in the maize genome data on the basis of polymorphism information contents (PIC) value and distinct amplification products. These markers detected 5 to 24 alleles, with an average of 13.69. The mean PIC value was 0.865 and ranged from 0.716 to 0.942. The unweighted pair-group method with arithmetical average (UPGMA) analysis was conducted for constructing the dendrogram using Jaccard's genetic similarity coefficient. The genetic similarity varied from 0.07 to 0.824. Thirteen microsatellite markers identified all 90 maize varieties and parental lines. The maize varieties were clustered into 5 major groups consistent with type and pedigree information. The microsatellite profile database of maize varieties could be used to select comparative varieties through genetic relationship analysis between existing varieties and candidate varieties in distinctness tests.