• 대한수학교육학회지:학교수학
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• 제3권2호
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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.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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• pp.394-397
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• 2004

대부분의 건설현장에서 기후에 대한 공기산정은 정확한 자료 없이 현장관리자의 경험과 직관에 의해 작업불능일수를 정함으로써 잦은 공기조정으로 인한 경제적 손실은 물로 공사주체들 간의 이해관계에서도 많은 문제점을 안고 있다. 더욱이 최근 대두되고 있는 기후변화는 기후예측을 보다 어렵게 만들고 있다. 따라서 본 연구는 공기에 영향을 미치는 기후요소 중 기온과 강우에 대하여 지역별 특징과 기후변화를 분석하고, 현행 산술평균방식을 산정기간별로 예측오차를 비교분석하여 최적의 산정방식을 제안하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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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.

• 한국정밀공학회지
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• 제9권4호
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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.

• 산업경영시스템학회지
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• 제28권4호
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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.

• 한국수학교육학회지시리즈A:수학교육
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• 제51권4호
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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.

• 한국기계가공학회지
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• 제11권5호
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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.

• 대한기계학회논문집
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• 제18권4호
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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.

• 대한방사선기술학회지:방사선기술과학
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• 제20권1호
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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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• 제43권3호
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• pp.367-375
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• 2016

국내에서 육성된 옥수수 90 품종 및 자식 계통에 대하여 microsatellite 마커를 활용하여 DNA 프로파일 데이터베이스를 구축한 다음 공시품종에 따른 유전적 유사도 분석 및 품종식별력 검정에 대한 연구를 수행하였다. 옥수수 90품종을 100개의 microsatellite 마커로 검정하고 대립유전자의 패턴이 우수하고 다형성 정도가 높은 13개를 선정하여 분석하였을 때 대립유전자의 수는 5 ~ 24개까지 다양하게 분포하였고 평균 대립유전자의 수는 13.69개로 높았다. PIC 값의 경우도 0.716 ~ 0.942 범위에 속하였고 평균값은 0.865로 아주 높았다. 옥수수 90품종 및 계통에 대하여 UPGMA 분석에 의한 계통도를 작성하였을 때, 옥수수의 품종 유형 및 품종 육성 계보에 따라 5개의 대그룹으로 나누어졌다. 본 연구에서 구축됨 옥수수 자식계통 및 품종별 microsatellite DNA 프로파일 데이터베이스는 신품종과 기 육성된 품종과 유전적 유사도 분석이 가능하기 때문에 품종보호출원시 대조품종 선정 및 품종진위성과 관련된 종자분쟁에 매우 유용하게 활용될 수 있을 것이다.