• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.195-196
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• 2022

Insulation material absorption rate is closely related to thermal conductivity. In Korea, there is no study on the change of insulation material in a long-term continuous exposure environment. In this study, basic data on the long-term durability of insulation materials were obtained by measuring the absorption rate of insulation materials over time. For the purpose of providing, as a result of the measurement, PIR class2 No.2 and PIR noncombustible show similar absorption rate trends, which is thought to be due to the fact that both are made of rigid urethane foam, and flame retardant EPS has the highest absorption rate except for PF. This is thought to be because there is a space for absorption between the beads and the beads. In the case of XPS, it is thought that the reason for showing the lowest absorption rate is that because it is produced by extrusion, it has a high density and thus has less space for moisture to penetrate.

• Journal of the Korean Data and Information Science Society
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• 제24권4호
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• pp.713-721
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• 2013

모유는 아기에게 필요한 풍부한 영양분을 고루 갖춘 우수한 영양 공급원으로 특히 미숙아의 성장발달에 매우 중요하지만 미숙아의 모유수유 실천정도는 매우 저조한 실정이다. 본 연구는 재태 연령을 기준으로 34주 미만 미숙아, 34주 0일에서 36주 6일의 후기 미숙아, 37주 0일에서 38주 6일의 조기 만삭아를 분만한 어머니를 대상으로 모유수유 실천율과 모유수유 임파워먼트를 비교 분석하기 위함이다. 병원 퇴원 당시 모유수유 실천율은 세 군 간에 유의한 차이가 있었다. 즉, 후기 미숙아와 34주 미만 미숙아의 모유수유 실천율은 조기 만삭아의 모유수유 실천율보다 낮았다. 또 모유수유 임파워먼트 총점에서도 34주 미만 미숙아 모와 후기 미숙아 모는 조기 만삭아 모보다 더 낮은 것으로 나타났다. 이는 국내 모유수유 실천율을 향상시키기 위해 미숙아 모를 대상으로 한 모유수유 증진 방안이 마련되어야 하고 이 때 모유수유 실천에 대한 자신감 부여가 필요함을 나타내는 결과이다.

• ETRI Journal
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• 제29권2호
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• pp.201-211
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• 2007

This paper focuses on the scheduling problem with the objective of maximizing system throughput, while guaranteeing long-term quality of service (QoS) constraints for non-realtime data users and short-term QoS constraints for realtime multimedia users in multiclass service high-speed uplink packet access (HSUPA) systems. After studying the feasible rate region for multiclass service HSUPA systems, we formulate this scheduling problem and propose a multi-constraints HSUPA opportunistic scheduling (MHOS) algorithm to solve this problem. The MHOS algorithm selects the optimal subset of users for transmission at each time slot to maximize system throughput, while guaranteeing the different constraints. The selection is made according to channel condition, feasible rate region, and user weights, which are adjusted by stochastic approximation algorithms to guarantee the different QoS constraints at different time scales. Simulation results show that the proposed MHOS algorithm guarantees QoS constraints, and achieves high system throughput.

• 융합경영연구
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• 제12권3호
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• pp.1-12
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• 2024

Purpose: As a major economy attracting foreign investment, China is currently facing significant international economic pressure due to the appreciation of the RMB. Additionally, China is at a critical period of socio-economic development, where foreign direct investment (FDI) plays an indispensable role in stabilizing economic growth, adjusting industrial structure, and promoting economic transformation. Research design, data and methodology: This paper focuses on the relationship between RMB exchange rate expectations and FDI. It examines the magnitude of their relationship through empirical research using cointegration tests, Granger causality tests, and BVAR (Bayesian Vector Autoregression) analysis. Results: The comprehensive study of the empirical results in this paper concludes that there is a long-term cointegrated relationship between China's RMB exchange rate expectations and foreign direct investment, indicating that their relationship is stable in the long run. It is also found that RMB exchange rate expectations have a significantly positive impact in the short term, but this impact is not significant in the long term. Conclusions: The paper also considers the possibility of establishing a China-EU Free Trade Area in the future and offers policy recommendations regarding RMB exchange rate expectations and foreign direct investment.

• Journal of Positioning, Navigation, and Timing
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• 제8권4호
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• pp.209-214
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• 2019

Precise point positioning (PPP) requires precise orbit and clock products. International GNSS service (IGS) real-time service (RTS) data can be used in real-time for PPP, but it may not be possible to receive these corrections for a short time due to internet or hardware failure. In addition, the time required for IGS to combine RTS data from each analysis center results in a delay of about 30 seconds for the RTS data. Short-term orbit prediction can be possible because it includes the rate of correction, but the clock correction only provides bias. Thus, a short-term prediction model is needed to preidict RTS clock corrections. In this paper, we used a long short-term memory (LSTM) network to predict RTS clock correction for three minutes. The prediction accuracy of the LSTM was compared with that of the polynomial model. After applying the predicted clock corrections to the broadcast ephemeris, we performed PPP and analyzed the positioning accuracy. The LSTM network predicted the clock correction within 2 cm error, and the PPP accuracy is almost the same as received RTS data.

• 정보저장시스템학회논문집
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• 제8권2호
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• pp.50-55
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• 2012

Optical disks are widely used in libraries and archives as digital data media due to their long-term storage stability. Though archive-grade optical disks are already available on the market, there is a relative less focusing on the reliable recording conditions. Commercial BD-R media were recorded at various recording speeds with the maximum speed of 6X, and tested at the acceleration aging conditions. Through the evaluation of long-term storage features by the data stability test, lower recording speed of 2x resulted in better long-term storage stability. In addition, degradation aspects of unstable long-term storage feature at outer region of disk were discussed.

• Communications for Statistical Applications and Methods
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• 제24권4호
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• pp.325-337
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• 2017

In this paper, we proposed a new long-term lifetime distribution with four parameters inserted in a risk competitive scenario with decreasing, increasing and unimodal hazard rate functions, namely the Weibull-Poisson long-term distribution. This new distribution arises from a scenario of competitive latent risk, in which the lifetime associated to the particular risk is not observable, and where only the minimum lifetime value among all risks is noticed in a long-term context. However, it can also be used in any other situation as long as it fits the data well. The Weibull-Poisson long-term distribution is presented as a particular case for the new exponential-Poisson long-term distribution and Weibull long-term distribution. The properties of the proposed distribution were discussed, including its probability density, survival and hazard functions and explicit algebraic formulas for its order statistics. Assuming censored data, we considered the maximum likelihood approach for parameter estimation. For different parameter settings, sample sizes, and censoring percentages various simulation studies were performed to study the mean square error of the maximum likelihood estimative, and compare the performance of the model proposed with the particular cases. The selection criteria Akaike information criterion, Bayesian information criterion, and likelihood ratio test were used for the model selection. The relevance of the approach was illustrated on two real datasets of where the new model was compared with its particular cases observing its potential and competitiveness.

• 대기
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• 제19권3호
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• pp.243-253
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• 2009

In other to interpret the long-term variations of sunshine duration, cloud lifetime, and precipitation intensity observed in and around Seoul and Busan for the period from 1986 to 2005, aerosol indirect effect was employed and applied. For the identification of long-term trend of aerosol concentration, observed visibility and AOT of AERONET sunphotometer data were also used over the same regions. The result showed that the time series of visibility was decreased and those of AOT increased, especially trends were remarkable in 2000s. In both regions, occurrence frequencies of observed cloudiness (cloud amount ${\leq}6/10$) and strong precipitation (rain rate > $0.5mmhour^{-1}$) have been steadily increased while those of cloudiness (cloud amount > 7/10) and weak precipitation (rain rate ${\leq}0.2mmhour^{-1}$) decreased. These results are corresponding to the trend of both visibility and AERONET data, implying the aerosol indirect effect that makes size of cloud droplet reduce, cloud life-time longer and precipitation efficiency decreased. Our findings demonstrate that, although these phenomena are not highly significant, weather and climate system over Korean urban area have been changed toward longer lifetime of small cloudiness and increasing precipitation intensity as a result of increased aerosol indirect effect.

• 대한간호학회지
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• 제44권1호
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• pp.21-30
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• 2014

Purpose: This study was conducted to explore the impact of registered nurse/nurses' aid (RN/NA) staffing and turnover rate on inpatient health outcomes in long term care hospitals. Methods: A secondary analysis was done of national data from the Health Insurance Review and Assessment Services including evaluation of long term care hospitals in October-December 2010 and hospital general characteristics in July-September 2010. Final analysis of data from 610 hospitals included RN/NA staffing, turnover rate of nursing staff and 5 patient health outcome indicators. Results: Finding showed that, when variables of organization and community level were controlled, patients per RN was a significant indicator of decline in ADL for patients with dementia, and new pressure ulcer development in the high risk group and worsening of pressure ulcers. Patients per NA was a significant indicator for new pressure ulcer development in the low risk group. Turnover rate was not significant for any variable. Conclusion: To maintain and improve patient health outcomes of ADL and pressure ulcers, policies should be developed to increase the staffing level of RN. Studies are also needed to examine causal relation of NA staffing level, RN staffing level and patient health outcomes with consideration of the details of nursing practice.

• 보건의료산업학회지
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• 제5권2호
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• pp.105-117
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• 2011

The purpose of this study is to investigate evaluation and improvement of long-term care hospitals for changing long-term care hospitals fee system. Data were collected from 104 CEOs in nationwide long-term care hospitals using structured self-administered questionnaires during August 17 to 31, 2009. Major results of the empirical analysis are as follows; first, to change fixed sum medical fee per day caused to decline the level of geriatric service in 87% of CEOs. Second, 79% of CEOs were dissatisfied with changing fixed sum medical fee per day, and 47% of them were dissatisfied with graded fee for doctor and nurse management. Finally, they suggested that to specialize and to differentiate of long-term care hospitals will drive to improve long-term care hospitals function and to measure workforce based on rate of filled vacancies will increase efficiency and productivity of doctor and nurse management.