• 수산경영론집
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• 제49권3호
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• pp.85-99
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• 2018

This study is to compare and evaluate the estimating method of WTP(willingness to pay) for the valuation of oceans and fisheries resources with non-market goods characteristics using contingent valuation method. In general, when estimating parameters of the WTP function, we should take into account the assumption of probability distribution, inclusion of covariates, method of inducement of payment, and the treatment of 0 payment intention and resistance responses. This study utilizes survey data that was used to estimate the value of fisheries resource protection zones, with a total of 1,200 samples. The main results of this study are summarized as follows: First, the final willness to pay amount is estimated at a statistical significance of less than 1 percent, and the distribution of the final willness to pay amount is from \6,926 of the double bounded dichotomous model to \10,721 of the spike model. Second, the willness to pay amount based on assumptions about the normal and logistic probability distributions are estimated to be \9,429 and \9,370 respectively, so there was no significant difference. Third, the willness to pay amount of the single bounded dichotomous model and the double bounded dichotomous model are estimated to be \8,951 and \6,926 respectively, making a relatively large difference. Fourth, the willness to pay amount of the model without covariates and the model with covariates are estimated to be \9,429 and \8,951, respectively, so the willness to pay amount is underestimated when the covariates are included. Fifth, the Spike model that considers zero payment intention and resistance response estimates \10,405 as the highest payment in this study. Finally, the CVM analysis guidelines proposed by the Korea Development Institute (KDI) are estimated to be \9,749 and \10,405 respectively, depending on including no covariates and with covariates. Compared to other models, the final willness to pay amount is not estimated underestimated. Therefore this study suggests the use of KDI's guidance under government public policy projects. In view of these results, the estimating model for willness to pay amount model will be selected by considering the sample size, the suitability of the model, the sign of the estimated coefficient, the statistical significance, the ratio of the zero payment intention and the payment rejection. And, for CVMs on government public policy projects, it is desirable to estimate by the method proposed by the KDI.

• 한국방사선학회논문지
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• 제13권3호
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• pp.407-414
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• 2019

최근 NCS 교육기반으로 개편된 이후 NCS에서 요구하는 직업기초능력과 직무능력을 향상하기 위한 다양한 학습방법이 모색되고 있으며, 그에 따른 평가방법이 절실히 필요하다. 본 연구에서는 전문대학 방사선과 학생들을 대상으로 NCS 교육과정에서 요구하는 직무능력과 직업기초능력을 향상시키기 위하여 평가 사례로 메타인지 학습과 하브루타 학습을 적용하여 평가하였다. 적용한 결과, 메타인지 학습 대응 표본 통계량에서는 사전 메타인지학습 설문을 5점 척도로 했을 경우 평균 2.6883, 사후 메타인지 학습 설문 평균은 4.2468로 나타나 약 1.55점 향상되었다. 상관계수는 0.782, 유의확률은 0.045로 유의하게 나타났다. 하브루타 학습 대응 표본 통계량에서는 사전 하브루타 학습 설문을 5점 척도로 했을 경우 평균 3.1515, 사후 하브루타 학습 설문 평균은 4.3853으로 나타나 약 1.23점 향상되었다. 상관계수는 0.631, 유의확률은 0.049로 유의하게 나타났다. 메타인지 학습과 하브루타 학습이 상관관계가 있는지 이변량 상관계수를 통하여 알아 본 결과, 메타인지의 평균은 3.4675, 하브루타의 평균은 3.7684로 나타났으며 메타인지 학습과 하브루타 학습은 -0.042의 상관관계를 가지며 통계적으로 유의한 차이는 없는 것으로 나타났다. 따라서 직무능력을 향상시키기 위한 학습방법은 교과목 특성을 고려하여 적용해야 할 것이다.

• 한국응용과학기술학회지
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• 제40권5호
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• pp.936-944
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• 2023

본 연구는 황련 추출물을 함유한 에센스가 피부 장벽 강화와 보습에 미치는 영향을 검증하는데 목적을 두고 있다. 황련 추출물을 함유한 에센스를 22명의 피험자에게 4주간 사용하게 한 후 지정한 상박 부위의 경피 수분 손실량(g/m²h)과 수분량(A.U.)을 측정하였다. Vapometer를 이용하여 경피 수분 손실량을 측정한 결과 사용 전 14.82±4.01에서 4주 사용 후 11.08±2.55로 나타났고 유의 확률은 p<0.001로 25.27% 유의하게 감소하였다. Corneometer로 측정한 피부 수분량은 사용 전 31.73±8.09에서 사용 후 46.73±7.45로 나타났고 유의 확률은 p<0.001로 47.26% 증가하였으며 설문을 통한 효능평가에서 피부 이상 반응 없이 두 항목 모두 100% 개선된 것으로 나타났다. 이와 같은 결과로 황련 에센스는 피부 장벽 강화와 보습에 효과적인 것으로 확인되었고 이는 향후 황련 추출물의 다양한 활성을 이용한 화장품 개발에 초석이 될 것으로 기대된다.

• 대한토목학회논문집
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• 제13권2호
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• pp.141-149
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• 1993

수력에너지 생산량은 추계학적인 저수지 유입량에 지배되므로 전력량 판매 계약에는 이를 반영하여 합리성을 보장해야 할 필요가 있다. 본 연구에서는 유입량의 신뢰도별로 저수지조작(貯水池操作)을 수행하여 최적 신뢰도 및 이에 따른 최적 전력 판매계약량을 결정하는 방법을 제시하였다. 목적함수에는 전력생산량이 신뢰도를 벗어나는 위험에 대한 손실함수를 도입하고, 손실계수의 범위를 제시하였다. 여기서 손실은 계약량을 공급하지 못할 경우 지불해야 할 벌칙량을 의미하고 신뢰도는 저수지 유입량에 대한 초과 확률과 같고, 이 때 확률밀도함수는 대수정규분포를 5% 유의수준에서 채택하였다. 최적의 신뢰도를 결정하기 위하여 오목함수 범위에서 황금비 조사 기법을 썼으며, 신뢰도별 최대 수력 에너지를 얻기 위해 증분 동적계획 기법으로 저수지 조작을 수행하였다. 본 연구의 적용대상으로 대청 다목적댐 및 수력발전소를 택하여 손실계수, 최적 신뢰도 및 계약 발전량을 구하였다.

• Nuclear Engineering and Technology
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• 제53권7호
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• pp.2364-2370
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• 2021

The ⁿMCP (Neutron sensitive microchannel plate) combined with advanced readout electronics is widely used in energy selective neutron imaging because of its good spatial and timing resolution. Neutron detection efficiency is a crucial parameter for the ⁿMCP. In this paper, a mathematical model based on the oblique cylindrical channel and elliptical pore was established to calculate the neutron absorption probability, the escape probability of charged particles and overall detection efficiency of ⁿMCP and analyze the effects of neutron incident position, pore diameter, wall thickness and bias angle. It was shown that when the doping concentration of the ⁿMCP was 10 mol%, the thickness of ⁿMCP was 0.6 mm, the detection efficiency could reach maximum value, about 24% for thermal neutrons if the pore diameter was 6 ㎛, the wall thickness was 2 ㎛ and the bias angle was 3 or 6°. The calculated results are of great significance for evaluating the detection efficiency of the ⁿMCP. In a subsequent companion paper, the mathematical model would be extended to the case of the spatial resolution and detection efficiency optimization of the coating ⁿMCP.

• Genomics & Informatics
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• 제19권1호
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• pp.5.1-5.11
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• 2021

Head and neck squamous cell carcinoma (HNSCC) is the most frequent type of head and neck cancer that usually arises from the mucosal surfaces of several organs including nasal cavity, paranasal sinuses, oral cavity, tongue, pharynx, and larynx. The Wnt signaling pathway is a crucial mechanism for cellular maintenance and development. It regulates cell cycle progression, apoptosis, proliferation, migration, and differentiation. Dysregulation of this pathway correlates with oncogenesis in various tissues including breast, colon, pancreatic as well as head and neck cancers. The present study aims to assess the gene alterations in the Wnt family of genes so as to derive an association with HNSCC. Computational approaches have been utilized for the identification of gene alterations in the Wnt family of genes. Several databases such as cBioportal, STRING, and UALCAN were used for the purpose. The frequency of alteration was high in case of Wnt family member 11 (5%). Gene amplification, deep deletions, missense and truncating mutations were observed in HNSCC patients. There was a marked difference in the gene expression profile of WNT11 between grades as well as normal samples. The survival probability measured using the Kaplan-Meier curve also presented with a significant difference among male and female subjects experiencing a low/medium level expression. The female patients showed less survival probability when compared to the male subjects. This provides the prognostic significance of the WNT11 gene in HNSCC. Taken together, the present study provides clues on the possible association of WNT11 gene alterations with HNSCC, which has to be further validated using experimental approaches.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권2호
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• pp.520-541
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• 2023

In CRNs, SS is of utmost significance. Every CR user generates a sensing report during the training phase beneath various circumstances, and depending on a collective process, either communicates or remains silent. In the training stage, the fusion centre combines the local judgments made by CR users by a majority vote, and then returns a final conclusion to every CR user. Enough data regarding the environment, including the activity of PU and every CR's response to that activity, is acquired and sensing classes are created during the training stage. Every CR user compares their most recent sensing report to the previous sensing classes during the classification stage, and distance vectors are generated. The posterior probability of every sensing class is derived on the basis of quantitative data, and the sensing report is then classified as either signifying the presence or absence of PU. The ISVM technique is utilized to compute the quantitative variables necessary to compute the posterior probability. Here, the iterations of SVM are tuned by novel GO-PSA by combining GOA and PSO. Novel GO-PSA is developed since it overcomes the problem of computational complexity, returns minimum error, and also saves time when compared with various state-of-the-art algorithms. The dependability of every CR user is taken into consideration as these local choices are then integrated at the fusion centre utilizing an innovative decision combination technique. Depending on the collective choice, the CR users will then communicate or remain silent.

• Communications for Statistical Applications and Methods
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• 제31권1호
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• pp.1-35
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• 2024

The assumption of homoscedasticity is one of the most crucial assumptions for many parametric tests used in the biological sciences. The aim of this paper is to compare the empirical probability of type I error and the power of ten parametric and two non-parametric tests for homoscedasticity with simulations under different types of distributions, number of groups, number of samples per group, variance ratio and significance levels, as well as through empirical data from an agricultural experiment. According to the findings of the simulation study, when there is no violation of the assumption of normality and the groups have equal variances and equal number of samples, the Bhandary-Dai, Cochran's C, Hartley's Fmax, Levene (trimmed mean) and Bartlett tests are considered robust. The Levene (absolute and square deviations) tests show a high probability of type I error in a small number of samples, which increases as the number of groups rises. When data groups display a nonnormal distribution, researchers should utilize the Levene (trimmed mean), O'Brien and Brown-Forsythe tests. On the other hand, if the assumption of normality is not violated but diagnostic plots indicate unequal variances between groups, researchers are advised to use the Bartlett, Z-variance, Bhandary-Dai and Levene (trimmed mean) tests. Assessing the tests being considered, the test that stands out as the most well-rounded choice is the Levene's test (trimmed mean), which provides satisfactory type I error control and relatively high power. According to the findings of the study and for the scenarios considered, the two non-parametric tests are not recommended. In conclusion, it is suggested to initially check for normality and consider the number of samples per group before choosing the most appropriate test for homoscedasticity.

• 한국보건간호학회지
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• 제5권2호
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• pp.67-75
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• 1991

This study was conducted to evaluate the difference of staphylococcal colonization between lactating mothers and nursery stares. Samples were obtained from the hands and noses of the newborn(admitted to S Univ. hospital's nursery from 1991. 5. 23 to 6. 8), their mothers and nursery staffs. They were cultured, and then the presence/absence of pathogenic staphylococci in them were analyzed by Fisher exact probability test which led to these conclusion of significance as follows: 1. No differences were detected in pathogenic rate of nasal swab culture between breast~fed newborns and formula-fed ones. 2. Delivery type and hospitalization the ones from the brest-fed newborns show high rate of Sta. aureus coa(+). In case of either C-sec delivery or long (more than 4 days) hospitalization, formula-fed ones in case of NSVD or short (less than 3 days) hospitalization. 3. The ones from breast feeding mothers show higher sta. aureus coa(+) than those from nursery staffs, which was of no significance statistically. Considering nursery staffs only, however, the comparison of those with the data in April indicates that the pathogen rate is higher for hand than nose, and Sta aureus coa(+) for hand is far lower in June than in April, which was statistically significant. These results lead us to infer that newborn infection in hospitalization could be largely reduced by maintaining the ordinary hygienes. Such as the handwashing of mothers as well as nursery staffs (directly involved in newborn care) Thus the pre-enterance hand washing of a mother who visits the nursery only for breast feeding (without any other medical responsibility) should be done, like other medical agents, with $0.05\%$ chlorhexidine antiseptics rather than simple soap cleansing; the one 'that is worth emphasizing thoroughly.

• 산업진흥연구
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• 제5권1호
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• pp.13-20
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• 2020

본 연구는 재활용수의 선택적 자동공급이 가능한 플라스틱류 양변기 소비자 선호도에 관한 연구로서 연구분석 결과를 요약하면 다음과 같다. 첫째, 성별, 연령대별 플라스틱류 양변기 디자인 외형에 대한 선호도는 성별에서는 남녀 모드 C 타입을 선호하였고, 카이제곱 검정결과 자유도가 2일 때 유의확률은 .044로 유의성이 P<.05이므로 통계적으로 유의한 것으로 확인 할 수 있었다. 연령에서는 10대, 40대, 50대 이상은 C 타입, 20대, 30대는 B 타입을 선호하는 것으로 분석되었으나 통계적으로 유의하지 못한 것으로 분석되었다. 둘째, 일반적 특성에 따른 외형디자인 기준에 대한 선호도의 집단 간 차이는 성별, 연령, 지역, 학력, 연봉에서모두 안정성(안정적인 외관)을 선호하였으나, 카이제곱 검증 결과, 통계적으로 유의하지 못한 것으로 나타나 집단 간 차이는 없는 것으로 분석되었다. 본 연구는 플라스틱류 소재의 양변기를 제품화함으로써 주요 생산경비 절감 등 경쟁력 및 생산성 향상을 높이는데 본 연구의 시사점이 있다.