• 대한수학회보
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• 제56권4호
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• pp.815-827
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• 2019

It is well known that the denominator of the Dedekind sum s(c, d) divides 2 gcd(d, 3)d and that no smaller denominator independent of c can be expected. In contrast, here we prove that we usually get a smaller denominator in S(H, d), the sum of the s(c, d)'s over all the c's in a subgroup H of order n > 1 in the multiplicative group $(\mathbb{Z}/d\mathbb{Z})^*$. First, we prove that for p > 3 a prime, the sum 2S(H, p) is a rational integer of the same parity as (p-1)/2. We give an application of this result to upper bounds on relative class numbers of imaginary abelian number fields of prime conductor. Finally, we give a general result on the denominator of S(H, d) for non necessarily prime d's. We show that its denominator is a divisor of some explicit divisor of 2d gcd(d, 3).

• Journal of Positioning, Navigation, and Timing
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• 제8권2호
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• pp.87-94
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• 2019

The Global Navigation Satellite System (GNSS) Real-Time Kinematic (RTK) positioning has been widely used in geodesy, surveying, and navigation fields. RTK can benefit enormously from the integration of multi-GNSS. In this study, we develop a GPS/BeiDou Navigation Satellite System (BDS) RTK integration algorithm for long baselines ranging from 128 km to 335 km in South Korea. The positioning performance with GPS/BDS RTK, GPS-only RTK, and BDS-only RTK is compared in terms of the positioning accuracy. An improvement of positioning accuracy over long baselines can be found with GPS/BDS RTK compared with that of GPS-only RTK and that of BDS-only RTK. The positioning accuracy of GPS/BDS RTK is better than 2 cm in the horizontal direction and better than 5 cm in the vertical direction. A lower Relative Dilution of Precision (RDOP) value with GPS/BDS integration can obtain a better positional precision for long baseline RTK positioning.

• KDI Journal of Economic Policy
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• 제46권2호
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• pp.45-74
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• 2024

The import content of export (ICE) has served as an indicator of global integration for several decades. It is defined as the share of imported products embodied in exports and can be interpreted as the relative degree of the utilization of global production network (GPN) over the domestic supply chain (DSC) in terms of 'value-added.' This paper proposes two new indicators of global integration. They are defined as the ratios of imports (foreign products) to gross output (domestic products) generated by exports and can be interpreted as the relative degrees of the utilization of GPN over DSC in terms of 'production.' Both indicators are easy to compute and can be compared between years, between countries, between industries, and between groups of industries. The paper applies the new indicators to the recent edition of the OECD's Input-Output Database. Finally, the paper shows that the recent slowdown in international trade is mostly due to the decrease in the international trade of intermediate goods, with significant implications regarding the future of global integration.

• Composites Research
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• 제32권6호
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• pp.382-387
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• 2019

상대습도와 온도가 PET 필름의 점탄성 특성에 미치는 영향을 조사하기 위해 RH-DMA를 이용하여 single frequency strain mode 시험, stress relaxation mode 시험, creep 시험을 수행하였다. 상대습도는 10%, 30%, 50%, 70%, 90%를 적용하고 온도는 single frequency strain mode 시험의 경우 30~95℃, stress relaxation mode 시험의 경우 30℃ 와 70℃, creep 시험의 경우 5~95℃를 고려하였다. 연구결과에 따르면 상대습도가 높아지면 저장탄성계수와 손실탄성계수는 낮아지며 손실탄성계수의 최대값은 상대습도의 변화에 큰 영향을 받지 않고 거의 일정해진다. 이완탄성계수는 초기에 급격히 감소하다가 일정한 값을 가지며 높은 온도에서는 상대습도의 변화에 민감해진다. 변형률 회복는 초기에 급격히 증가하며 온도가 높아지면 이완 탄성계수와 마찬가지로 상대습도에 민감하게 변한다. 크리프 컴플라이언스의 증가 정도는 온도가 높아지면 커지며 유리전이온도보다 온도가 높아지면 증가 정도는 더욱 커진다. 시간-온도 중첩법을 통해 구해지는 마스터 선도를 이용하면 상대습도와 온도 등의 운용 조건에서의 장기 성능을 예측할 수 있는 정보를 얻을 수 있다.

• 한국산학기술학회논문지
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• 제12권7호
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• pp.3053-3061
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• 2011

본 연구는 한국거래소의 코스닥증권시장에 상장된 기업들을 대상으로 연구개발투자와 기업가치 간의 관계를 살펴보았다. 주요 결과는 다음과 같다. 첫째, 표본기업 전체를 대상으로 실시한 분석결과, 연구개발투자는 기업가치와 역 U자 형태의 비선형적(nonlinear)인 관계를 지니는 것으로 나타났다. 이러한 비선형적인 관계는 연구개발투자가 일정한 범위까지 기업가치에 긍정적으로 기여하지만, 일정 수준을 초과하는 경우 오히려 기업가치에 부정적인 요인으로 작용할 수 있음을 의미한다. 둘째, 제조기업 및 IT기업 여부 등의 기업특성과 글로벌 금융위기 발생 시점을 기준으로 구분한 하위 집단의 분석결과, 대체로 연구개발투자와 기업가치 간에 역 U자 형태의 비선형적인 관계를 지니는 것으로 나타났다. 그러나 일부 하위 집단에서 양(+)의 선형적 관계가 발견되었고, 추정계수의 크기 및 통계적 유의성도 다양하게 나타났다. 이는 기업특성과 금융위기 등이 연구개발투자와 기업가치의 관계에 부분적으로 다른 영향을 미칠 수 있음을 의미한다. 이와 같이 본 연구의 결과는 연구개발투자를 결정하는 경영자와 관련 기업의 투자자에게 중요한 정보로 활용될 수 있다는 점에서 시사하는 바가 크다.

• 한국유기농업학회지
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• 제20권1호
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• pp.71-80
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• 2012

본 실험은 중부 지방에서 Rye(곡우)와 Triticale(신영)의 단, 혼파 실험을 통하여 생산성, 사료가치 및 가축사육능력을 조사하여 중부지방에 적합한 초종을 선별하고자 하였으며, 결과를 요약하면 다음과 같다. 동계 사료작물의 건물수량은 밭토양에서는 R+R이 5.20ton/ha로 가장 많았으나 R, T+R과 유의한 차이는 없었고, 논토양에서는 R+H가 5.20ton/ha로 가장 많았지만 T+H, R과의 유의한 차이는 없었다. 또한 모든 시험구에서 단파구에 대한 혼파구의 상대수량이 1.00보다 높아 혼파효과가 입증되었다. 상대사료가치는 밭토양, 논토양 모두 Triticale 혼파구에서 다른 시험구와 유의한 차이를 보였다. 가축사육능력은 $K_{CP}$와 $K_{TDN}$의 평균값으로 비교해 보았을 때, 밭토양에서는 R+R이 2.75, 논토양에서는 T+H가 2.84로서 가장 높은 값을 보였다. 이상의 결과로 볼 때 중부 지방에서 동계 사료작물 생산에 있어서 가장 적합한 초종은 밭토양에서는 Rye+Red clover 혼파이며, 논토양에서는 Triticale+Hairy vetch 혼파라고 판단된다.

• 품질경영학회지
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• 제48권1호
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• pp.125-147
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• 2020

Purpose: This study would measure the users'perceived overall quality level of A automobile Company, which has leading market power in the domestic automobile market and analyze the causal relationships in the quality value process Model to quality capability, customer value and loyalty based on that. Especially, this study would analyze the relative impacts of the users'perceived risks appearing in the quality value process model of the formation of Quality Factors(QF), Customer Value(CV), and Customer Loyalty(CL) and analyze the moderating effect of the causal relationships among the components. Methods: For an analysis of causal relationships connected to QF, CV, and CL of the customers who purchased Auto manufacturer A's automobile users, 179 users who used within 3 years were utilized as samples for the analysis. As for QF, based on the Garvin(1988), the QF of automobiles were redesigned. For a structural equation analysis of the entire research model, the PLS(S(Partial Least Square) model was utilized. Results: As a result of an analysis, R2 of CV and CL was 0.652 for CV and 0.664 for CL, which was a very stable Goodness of fit. As a result of an analysis of the hypotheses of QF and CV, automobile performance, conformance, aesthetics, serviceability, and durability. In addition, it turned out that the perceived risk had a moderating effect on convenience, service availability, and perceived quality. Conclusion: This study found that the perceived quality risk appearing among automobile users had negative effects on the quality value process model to QF, CV and CL. In contrast, there were factors not affecting the users'quality value process in spite of the perceived risk. These factors can suggest important managerial implications in that they can be utilized as Auto manufacturer A's market-dominant strengths.

• 대한간호학회지
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• 제4권2호
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• pp.144-158
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• 1974

This study was undertaken in an attempt to; 1) measure value orientation of nursing activities, 2) identify the relationship between nurse's role perception and patient's expectation, and 3) evaluate the pattern of nursing education and nursing service administration. 203 hospitalized adults and 203 professional nurses from 11 general hospitals in Seoul during the period of July to December 1973 were tested according to questionnaire based on 4 categories of clinical nursing activities, 1) physical care, 2) observation and control, 3) psycho-social care and 4) therapeutic measures. Results of the study are as follows: 1. Nurses were more concerned than patients in the physical care category. Significant difference was revealed by p<.01 level (t=2.800). Mean value score of nurses was average (2.84), and mean value score of patients was relative' y low (2.49). None of the physical care category questionnaire items were over 3.5. 2. Respondents from hospitals of total care system revealed significant difference in the physical care category by P〈.025 level. (t=2.242). Mean value score of both group were average level (nurse 2.90, patient 2.53), nurses showed higher concern. 3. Difference between nurse's role perception and patient's expectation in observation and control category was revealed non- significance by p〉0.05. level (t=1.238). Mean value score of both group revealed relatively high (nurse=3.44, patient 3.19). 4. Difference between nurse's role perception and patient〉expectation in psycho-social cart category revealed non- significance by p〉.05 level (t=0.758), Mean value score of both group revealed average level (nurse =2.71, patient =2.53), 5. Non- significant difference was noted between B. S. N. and diploma nurse's role perception in the psycho- social care category by p> 0.1 level (t=0.316). 4. Difference between nurse's role perception and patient's expectation in the rapeutic me assures category revealed non- significance by p〉0.05 level) t=0.503). Horses showed high concern by mean value score 3.56 level and patients relatively high by 3.41. All items of this category revealed very high or relatively high value score.

• 분석과학
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• 제31권6호
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• pp.240-246
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• 2018

본 연구에서는 GD-MS를 활용하여 원소 별 함량이 다른 세 종류의 알루미늄 매질의 표준 시료를 분석하였다. 13 종의 원소(Mg, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Sn, Pb)에 대해 검량 곡선을 작성하고 그 기울기를 RSF(Relative sensitivity reference)로 확립하였다. 검량 곡선은 X축을 IBR(Ion beam ratio)로, Y축을 표준 시료의 인증 값으로 작성하였다. 검량 곡선의 정밀도와 직선성을 평가하기 위해 RSD(Relative standard deviation)와 결정 계수를 계산하였다. 그 결과 모든 원소의 RSD는 10 %이내로 높은 정밀도를 나타냈다. 바나듐, 니켈 그리고 갈륨 원소를 제외한 대부분의 원소들은 결정 계수가 0.99 이상으로 1에 가까운 값을 얻어 직선성이 우수했다. 바나듐, 니켈 그리고 갈륨 원소는 결정 계수가 0.90~0.95 범위로 비교적 낮은 직선성을 나타냈으며, 이는 좁은 농도 범위로 인한 오차로 판단된다. 바나듐, 니켈 그리고 갈륨 원소는 결정 계수는 낮지만 각각의 표준 시료 RSF와 기울기로 확립한 표준RSF(Standard-RSF)가 비슷하여 정량 분석을 위한 RSF로 활용 가능할 것으로 판단된다. 다른 매질의 시료에 표준RSF(Al matrix)를 적용 가능 여부와 실제 표준 값에 대한 오차를 확인하기 위해서 철 매질(Fe matrix)의 표준 시료를 분석하여 검증하였다. 구리 원소를 제외한 6 종(Al, Si, V, Cr, Mn, Ni) 원소의 오차율은 약 30 %로 나타났으며, 구리 원소는 측정을 방해하는 불순물 화합물의 영향으로 오차율이 크게 나타난 것으로 판단된다. 일반적으로 동위원소$^{63}Cu$는 $^{54}Fe^{2+}-^{36}Ar$ 간섭을 받고 $^{65}Cu$는 $^{56}Fe-Al^{3+}$간섭을 받는다. 이를 분해하기 위해서는 8000 이상의 분해능이 필요하다. 하지만, 높은 분해능은 이온의 투과도를 낮추기 때문에 미량원소 분석에 어려움이 있다. 구리 원소를 제외한 알루미늄 외 5종의 원소에 대해서는 비교적 적은 오차로 정량 분석이 가능한 것으로 확인되었다.

• 유통과학연구
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• 제12권4호
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• pp.73-83
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• 2014

Purpose - This study aims to classify and extend the consumer value of movie theaters into various values such as functional value, emotional value, social value, epistemic value, and conditional value based on the theory of consumption value by Sheth, Newman and Gross (1991). It also aims to verify the path structure of consumption value→customer satisfaction→behavior intention of movie theaters to confirm its generalization. Research design, data, and methodology - This study was conducted by collecting data on Kimpo university students from various areas in Incheon, Northern Seoul, Ilsan, Kyonggi Province, and Kimpo City. The survey was conducted by distributing 280 survey papers from Oct. 5 to 15, 2013 and collecting 238 of them. The final analysis used 208 questionnaires, after excluding 30 invalid responses. The statistical analysis of this study used the SPSS 19.0 statistics package. Results - The results of the survey are as follows: First, consumption values of movie theaters are classified into the following five groups: functional value, emotional value, social value, epistemic value, and conditional value. This study verified that consumption values play a role as a previous variable of customer satisfaction. Second, functional value, emotional value, and epistemic value have positive effects on customer satisfaction. On the other hand, social value and conditional value do not affect customer satisfaction. Finally, customer satisfaction has a positive impact on behavior intention. Theater users have an intention to re-use or recommend the movie theater they used when they are satisfied with a movie theater's physical environment and services. Conclusions - This study can provide academic and practical implications as follows based on the results mentioned above. First, academic implications can be found in that consumption values of movie theater users are classified into five values based on the theory of consumption value by Sheth et al. (1991). In the previous study, the service quality of a movie theater was studied based on the service quality of service encounters and a physical environment→customer satisfaction→behavior intention path structure. However, this study was verified by a consumption value→customer satisfaction→behavior intention path structure to classify consumption value, but not service quality or perceived value of quality, to confirm this generalization. Second, practical implications can be found in that the relative impact of consumption value of movie theaters on consumer satisfaction showed that functional value was followed by epistemic value and emotional value. In the previous study on movie theaters, previous variables of customer satisfaction were separated only by functional service quality including service encounters and physical environment; in some other studies, quality of service encounter had a direct effect on customer satisfaction. Accordingly, a marketing manager of a movie theater should develop various differentiated services by reflecting not only functional value such as service encounters and physical environment but also epistemic value and emotional value.