• 한국항공운항학회지
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• 제28권2호
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• pp.53-62
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• 2020

This study is to evaluate the accuracy of the meteorological information provided for the aircraft operating at low altitude. At first, it is necessary to identify crucial elements of weather information closely related to flight safety during low altitude flights. The study conducted a survey of pilots of low altitude aircraft, divided into pre-flight and in-flight phases, and reached an opinion that wind direction, wind speed, cloud coverage and ceiling and visibility are important items. Related to these items, we compared and calculated the accuracy of TAFs and METARs from Taean Airfield, Seosan Airport and Gunsan Airport because of their high number of domestic low-altitude flights. Accuracy analysis evaluated the accuracy of two numerical variables, Mean Absolute Error(MAE) and Root Mean Square Error(RMSE), and the cloud coverage which is categorical variable was calculated and compared by accuracy. For numeric variables, one-way ANOVA, which is a parameter-test, was approached to identify differences between actual forecast values and observations based on absolute errors for each item derived from the results of MAE and RMSE accuracy analyses. To determine the satisfaction of both normality assumptions and equivalence variability assumptions, the Shapiro-Wilk test was performed to verify that they do not have a normality distribution for numerical variables, and for the non-parametric test, Kruscal-Wallis test was conducted to determine whether or not they are satisfied.

• 응용통계연구
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• 제17권3호
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• pp.459-473
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• 2004

본 논문에서는 Breiman 등(1984)의 전체탐색법이 갖고 있는 변수선택 편향을 극복할 수 있는 알고리즘을 제안하였다. 제안한 알고리즘은 노드의 분리 변수를 선택하는 단계와 그 선택된 변수에 대해서만 이진분리를 위한 분리점을 찾는 단계로 나뉘어져 있다. 예측변수가 연속형 일 때는 스피어만의 순위상관계수에 의한 검정을 수행하고, 범주형일 때는 크루스칼-왈리스의 통계량에 의한 검정을 수행하여 통계적으로 가장 유의한 변수를 분리변수로 선택하였고 Breiman 등(1984)의 전체탐색법을 그 변수에만 적용하여 노드의 분리기준을 정하였다 모의실험 연구를 통해 Breiman등(19히)의 CART와 제안한 알고리즘을 변수선택 편의, 변수선택력파 평균제곱오차 측면에서 서로 비교하였다. 아울러 두 알고리즘을 실제 자료에 적용하여 효율을 서로 비교하였다.

• 산업경영시스템학회지
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• 제30권1호
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• pp.25-32
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• 2007

Automobile manufacturing companies should provide the products and service that can satisfy consumers who usually want various kinds of automobiles. This paper studied the relations among several demographic characteristics(gender, age, occupation, income) of consumers and automobile's attributes(engine performance, engine displacement, price, maintenance expenses, color, etc.) and preferred automobile(kind, size, company, price). For the relation research we established a model and related hypotheses and used a questionnaire survey, where 350 subjects were questioned. After the analysis, many statistically significant results are obtained : consumer's gender has relations with the preference for engine performance, engine displacement, price, color, and design; age has relations with the preference for engine displacement, maintenance expenses, free checking during A/S period, etc., occupation has relations with the preference for engine performance, engine displacement, price, maintenance expenses, fuel efficiency, etc. : income has relations with the preference for engine performance, engine displacement, price, maintenance expenses, mileage, reputation of car manufacturing companies, etc.; price and fuel efficiency has relations with the preference for car manufacturing companies. These results suggest the consumer-oriented sales of automobiles and are expected to be helpful for the effective strategy development of automobile marketing.

• 치위생과학회지
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• 제3권2호
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• pp.83-88
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• 2003

치과의료기관의 질관리를 위한 환자만족도 조사의 측정도구를 개발하고 평가하기 위하여 3회의 설문조사를 실시하였다. 51개소의 치과의료기관이 조사에 참아하였으며, 1017명이 응답하였고, 의료기관의 유형과 자료수집 방법에 따라 5개의 표본 집단으로 분류되었다. 표본 집단과 응답자의 특성에 따른 측정값, 신뢰도, 응답편견의 차이와 효과를 비교하기 위하여 정규성검정, t 검정, 분산분석, 카이스케어 검정, Kruscal-Wallis 검정을 실시하였다. 응답 편견과 균형척도에 의한 신뢰도, 타당도, 척도판별력의 저하효과가 추정되었다. 1. 측정 도구 문제를 평가하기 위한 독립 표본의 신뢰도를 비교한 결과 4개의 표본 집단의 내적 일관성의 신뢰도는 비슷한 수준을 보이고 있다. 2. 두 항목의 균형 척도에 대한 긍정 응답 편견률은 20%이며, 교육 수준에 따라 유의한 차이가 나타났다(P<0.05). 3. 환자 관점의 질 평가 척도의 측정값은 독립 표본 사이에 유의한 차이가 나타나지 않았으며, 연령에 따라 20대와 60대 사이에 유의한 차이가 나타나고 있다(P<0.01). 4. Likert 5점 척도로 구성된 총화평정척도의 평균은 4.16으로 좌측으로 편이되고 중앙값에 집중된 높은 첨도의 분포를 보였다. 5. 하위척도 사이의 평균차, 삼사분위값 대 일사분위값의 평균차가 95%의 신뢰구간에 포함되어 측정도구의 판별력은 매우 낮았다.

• 한국생활과학회지
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• 제22권2호
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• pp.365-374
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• 2013

The purposes of this study were to evaluate the color characteristics and color sensibility of mulberry/cotton blended fabrics dyed with indigo, the natural dye, and analyze effects of them on color preferences. The values of CIE $L^*$, $a^*$, $b^*$ $C^*$, h were calculated for the color characteristics of indigo-dyed fabrics, and their hue, value, and chroma were calculated according to the Munsell color system. Fifty male and female college students evaluated the color sensibility of nine types fabrics dyed with indigo on a seven-point scale. The data were analyzed by descriptive statistics, factor analysis, Kruscal-Wallis test, correlation analysis, and regression analysis. The mulberry/cotton blended fabrics naturally dyed with indigo showed the characteristics of PB color tones, low value, and low chroma. The color sensibilities of fabrics dyed with indigo were classified into four factors: 'classic', 'sporty', 'elegant' and 'natural'. There were significant differences according to the fibers and the repeating times of dyeing in the color sensibility for the fabrics. Cotton fabrics were evaluated to be more classic, sporty, elegant, and natural than the mulberry/cotton blended fabrics, and the deeper the color, the more classic, sporty, and elegant the fabric was evaluated. The students preferred the indigo dyed fabrics which have more classic, sporty, and natural sensibility. There were significant relationships between the color sensibilities and colorimetric properties of the fabrics dyed with indigo. The color preferences of the dyed fabrics with indigo were found to be influenced by the 'classic', 'sporty', 'natural' of color sensibility.

• 재활간호학회지
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• 제3권2호
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• pp.169-181
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• 2000

The purpose of this study was to identify the effect of follow-up care for stroke survivors on primary caregivers' quality of life. Quasi-experimental research was conducted in which an experimental group and a control group-each of 15 stroke survivors and their primary caregivers-were consecutively sampled. Data collected from July to September, 1999 by interview using a structured questionnaire with both the experimental and the control groups. After a month, the two groups were given the same questionnaire. The experimental group was also given a telephone follow-up every week for a month, as well as a home visit. The survey instruments used in this study were Saha and Cooper's "Modified Barthel Index" (11 items) for checking the stroke survivors' level of activities of daily living, and a modified form of Jeong's "Quality of life" (18 items) for primary caregivers' QOL level. The obtained data were analyzed by percentage, t-test, $X^2$-test, Kruscal-Wallis test, Spearman correlation coefficient by SAS/PC program. The results were as follows: 1. There was no significant difference in the stroke survivors' ADL level, though the level of the experimental group was higher than that of the control group. 2. There was a statistical difference in the before and after treatment of the primary caregivers' QOL level. In conclusion, the follow-up care program had a useful effect on the quality of life of primary caregivers.

• Restorative Dentistry and Endodontics
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• 제22권2호
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• pp.648-658
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• 1997

The purpose of this study was to compare the effects of various techniques on the quality and quantity of instrumentation in curved canals. Instrumentation time was evaluated too. Forty eight canals of resin blocks($35^{\circ}$) were divided into three groups and filed. In group A, 16 blocks were instrumented using a step-back technique with stainless steel(SS) K-file(Mani, Matsutani Seisakusho Co.,Japan). In group B, canals were prepared with SS K-files using the Endo-Angle (Nakanishi Dental MFG.CO.,LTD.,Japan). Group C was prepared using N i-Ti engine-driven instruments (Quantec Series $2000^{TM}$ system). Group A and B were filed from # 5 to # 25 at the apex followed by a 1 mm stepback technique, and the coronal half of the canals were flared with Gates Glidden burs(#2,3,4). Group C was instrumented from # 1 to # 8. After the instrumentation time was measured, canals were filled with India ink, and photographed, which to magnify the canal images 8 times. Using these photographs the apical portions were evaluated And scored from 1 to 4 according to the severity of ledging and zipping. On the same photographs, the area of the coronal two thirds of the canals were measured using a personal computer with the computer program Brain and Digitizer (SummaSketch III). The following results were obtained. 1. Instrumentation time was significantly shorter for group C, as opposed to group A and B(ANOVA, P<0.05). 2. The qualitative evaluation of the apical portions of the canals showed no significant difference between the groups(Kruscal-Wallis, p>0.05). 3. The area removed by group C was significantly smaller than group A and B(ANOVA, P<0.05).

• 산학경영연구
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• 제6권
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• pp.201-228
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• 1993

본 연구의 주 목적은 기업과 관련한 종교집단(기독교, 불교, 무종교)들이 기업의 준조세적 지출항목과 자발적 지출항목 및 각각의 금액에 대해 기업규모별로 어떠한 태도를 보이는가를 분석하기 위한 것이다. 연구방법은 설문지를 이용한 조사연구 방법을 사용하였으며, 자료분석 방법은 비 모수적 통계기법인 크루스칼-왈리스 검정과 월칵슨 부호검정을 사용하였다. 본 연구의 결과, 사회관련 지출항목 및 금액에 대해 기업규모별로 종교집단과 무종교집단간, 그리고 기독교 집단과 다른 집단간의 태도의 차이는 통계적으로 유의적인 차이가 아니었다. 이것은 우리나라에서 종교가 갖고 있는 사회윤리가 종교집단 구성원에게 체화되지 못함으로써 종교집 단간, 그리고 무종교집단과 구별되는 의식과 태도를 보이지 못하는 것에 기인하지 않을까 추론된다. 따라서 본 연구가 갖고 있는 한계안에서, 종교집단이라는 변수는 우리나라 사람들의 가치에 대한 태도를 연구할 때에 무시될 수 있는 변수라는 것을 시사한다.

• 한국가정과교육학회지
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• 제25권1호
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• pp.79-94
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• 2013

본 연구에서는 전통 의생활문화에 대한 인식을 고취시키고자 우리나라의 대표적 전통 천연염색 중 하나인 감즙염색을 이용한 학습자료를 제작하고 전통 의생활문화 체험이 가능한 교수-학습과정안을 개발하였다. 연구방법에 있어서 교육적 효과를 조사하기 위해서는 설문지를 작성하였고, 수업 실시 전과 후의 교육적 효과를 검증하기 위해서는 t-test, Kruscal-Wallis 검정 및 상관분석을 행하였다. 이를 고등학교 기술 가정과에 '감즙염색 직물을 이용한 생활소품 만들기' 주제로 수업에 적용하여 전통 이미지에 대한 인식의 변화와 학습에 대한 흥미도 및 태도 변화를 검토한 결과는 다음과 같다. 첫째, 감즙염색에 관해 연구해온 축적물로 독창적인 학습자료를 개발하여 감즙염색과 전통 의생활문화를 이해하기 위한 협동학습을 실시한 결과, 현대 감각을 살린 아이디어 소품이 창출되었다. 둘째, '청소년의 전통 의생활문화와 교육에 대한 인식'에 있어, 수업 전과 후의 차이를 나타내어 수업 후에 인식의 향상을 보였다. 나아가 조사대상을 상/중/하위 그룹으로 분류하여 분석한 결과, 긍정적인 변화에 있어서도 그룹 간 차이를 보였는데, 사전 점수가 가장 낮았던 하위 그룹에서 가장 높은 향상을 나타내었다. 셋째, '감즙염색 직물을 이용한 생활소품 만들기' 수업의 효과를 분석한 결과, 모든 문항에서 '보통' 이상으로 나타나, 학생들은 감즙염색 직물로 생활소품 만들기 체험을 통하여 전통 의생활문화에 대한 관심과 흥미도가 높아졌고 태도가 긍정적으로 변화하였음이 확인되었다. 넷째, 전통 의생활문화 인식과 그 교육에 대한 인식 간에는 문화에 대한 인식이 높은 학습자일수록 그 교육에 대한 인식도 높아 정적인 상관이 높은 것으로 나타났다. 이상과 같이 개발된 학습자료와 교수-학습과정안을 통한 전통 의생활문화 수업은 전통적인 천연염색과 의생활문화에 대한 가치와 의미를 이해하는 인식에서 향상된 변화를 가져왔고, 아이디어를 창출하는 교육적 효과를 가져왔다. 전통 의생활 문화 교육은 지속적이고 다면적인 심화된 연구와 현장교육의 상호작용이 이루어질 때 교육적 시너지효과가 더 발현될 것이다.

• 대한치과보철학회지
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• 제34권2호
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• pp.349-362
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• 1996

To determine the factors to affect on stone surface porosities produced from hydrogen gas of additional silicone, both putty and syringe type of 7 commercially different additional silicone impression materials(Blend-A-Scon, Correct VPS, Exaflex, Express, Extrude, Provil, Reprosil) were chosen and NewFujirock(GC) was poured into the impressions of detail-reproducing test block at 1, 15, 30, 45, 60 minutes after the impression materials had set and 4 specimens were made for each pouring time, each type of impression material, and each consisency and So, 280 specimens were made in total. The number of surface porosities of same area($2826 mm^2$) which were typically caused by hydrogen gas using the stereoscope(X 7.5) by two observers. Comparison of putty-syringe type and among the impression materials are tested by Kruscal-Wallis method and Mann-Whitney method(p<0.05). The results are as follows. 1. The number of porosities decreased as the pouring time of stone was delayed on both putty and syringe type of additional silicone materials. 2. The putty type significantly produced more porosities than syringe type except for the group of Reprosil.(p<0.05). 3. In case of putty type, the number of porosities increased as following order. Reprosil / Blend-A-Scon and Provil / Correct VPS and Extrude / Express and Exaflex. 4. In case of syringe type, Blend-A-Scon and Extrude produced no porosity and Exaflex and Provil at 30 minites, but Express produced porosities even at 60 minutes and the most. Additional silicone impression material releases hydrogen gas, and that fact can make the resulting die stone model useless. So, to minimize these adverse effects, it is desirable not to expose putty type of additional silicone on critical impression surface because putty type has a tendency to produce more porosities than syringe type. And it is important to have sufficient time before pouring the stone on impression because porosities produce less as time passes after setting of impression material. Also, there are differences among 7 additional silicone impression materials, so it is desirable to choose adequate brand of additional silicone for good laboratory work.