• 한국환경과학회지
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• 제20권12호
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• pp.1541-1551
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• 2011

This study applied the Bayesian method for the quantification of the parameter uncertainty of spatial linear mixed model in the estimation of the spatial distribution of probability rainfall. In the application of Bayesian method, the prior sensitivity analysis was implemented by using the priors normally selected in the existing studies which applied the Bayesian method for the puppose of assessing the influence which the selection of the priors of model parameters had on posteriors. As a result, the posteriors of parameters were differently estimated which priors were selected, and then in the case of the prior combination, F-S-E, the sizes of uncertainty intervals were minimum and the modes, means and medians of the posteriors were similar to the estimates using the existing classical methods. From the comparitive analysis between Bayesian and plug-in spatial predictions, we could find that the uncertainty of plug-in prediction could be slightly underestimated than that of Bayesian prediction.

• 성인간호학회지
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• 제25권2호
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• pp.170-182
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• 2013

Purpose: This study investigated the effectiveness of simulation training with a hybrid model of student nurses' performance ability and reported self confidence. Methods: A nonequivalent control group with pre-posttest was designed. Data collection was done during the first semester in 2012 at a college of nursing in Seoul. Nursing performance ability and reported self confidence related to taking care of patients with urinary problems were evaluated. The treatment group (n=96) received simulation training of a catheterization procedure with a hybrid model involving standardized patients and a mannequin. Nursing students in the comparison group (n=84) did not receive the simulation training but would receive it prior to their next clinical practicum's. Results: The treatment group showed a significantly higher performance ability and reported self confidence than that of the comparison group. The perceived helpfulness and contentment of the simulation training in experimental group was high. Conclusion: The findings of this study demonstrated that simulation with a hybrid model was effective in teaching skills prior to the clinical experience which suggests that skill development is not dependent on the actual clinical situation. Nurse educators should consider simulation training as a tool beyond that of clinical practicum.

• 한국음향학회지
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• 제32권2호
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• pp.174-180
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• 2013

본 논문은 HMM 기반의 TTS 시스템을 위하여 상호유사도 비율을 이용한 결정트리 기반의 문맥 군집화 알고리즘을 제안한다. 기존의 알고리즘들은 유사한 통계적 특성을 가지는 문맥종속 HMM을 하나로 묶고 있다. 그러나 기존의 알고리즘들은 결정트리의 나누어진 노드간의 통계적 유사도를 고려하지 않음으로 인하여 최종 노드 사이의 통계적인 차이를 보장하지 못한다. 제안한 알고리즘은 분리된 노드들 간의 통계적 유사도를 최소화하여 모델 파라미터의 신뢰도를 향상시킨다. 실험 결과를 통해 제안한 알고리즘이 기존의 알고리즘들에 비해 우수한 성능을 나타낸다는 것을 확인할 수 있다.

• Journal of Welding and Joining
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• 제24권1호
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• pp.77-87
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• 2006

Considering ferrite grain size in the base metal, the prediction model for $A_{c3}$ temperature and prior austenite grain size at just above $A_{c3}$ temperature was proposed. In order to predict $A_{c3}$ temperature, the Avrami equation was modified with the variation of ferrite grain size, and its kinetic parameters were measured from non-isothermal data during continuous heating. From calculation using a proposed model, $A_{c3}$ temperatures increased with increasing ferrite grain size and heating rate. Meanwhile, by converting the phase transformation kinetic model that predicts the ferrite grain size from austenite grain size during cooling, a prediction model for prior austenite grain size at just above the $A_{c3}$ temperature during heating was developed.

• 보건행정학회지
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• 제27권2호
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• pp.149-156
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• 2017

Background: This study was conducted to evaluate the performance of the Hierarchical Condition Category (HCC) model, identify potentially high-cost patients, and examine the effects of adding prior utilization to the risk model using Korean claims data. Methods: We incorporated 2 years of data from the National Health Insurance Services-National Sample Cohort. Five risk models were used to predict health expenditures: model 1 (age/sex groups), model 2 (the Center for Medicare and Medicaid Services-HCC with age/sex groups), model 3 (selected 54 HCCs with age/sex groups), model 4 (bed-days of care plus model 3), and model 5 (medication-days plus model 3). We evaluated model performance using $R^2$ at individual level, predictive positive value (PPV) of the top 5% of high-cost patients, and predictive ratio (PR) within subgroups. Results: The suitability of the model, including prior use, bed-days, and medication-days, was better than other models. $R^2$ values were 8%, 39%, 37%, 43%, and 57% with model 1, 2, 3, 4, and 5, respectively. After being removed the extreme values, the corresponding $R^2$ values were slightly improved in all models. PPVs were 16.4%, 25.2%, 25.1%, 33.8%, and 53.8%. Total expenditure was underpredicted for the highest expenditure group and overpredicted for the four other groups. PR had a tendency to decrease from younger group to older group in both female and male. Conclusion: The risk adjustment models are important in plan payment, reimbursement, profiling, and research. Combined prior use and diagnostic data are more powerful to predict health costs and to identify high-cost patients.

• Journal of Chest Surgery
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• 제32권11호
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• pp.984-988
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• 1999

Background: Donor-specific blood transfusion(DSBT) before organ transplantation has been demonstrated to prolong allograft survival; the mechanism of this effect has remained unclear. Only a few researches have been performed on this subject in our country. Material and Method: To investigate the effect of DSBT, we selected 5 donor recipient combinations using rats of pure strain such as PVG, ACI, and LEW. One ml of donor whole blood was transfused to each recipient through the femoral vein 7 days prior to transplantation. The donor heart was transplanted to the recipient's abdominal vessels heterotopically using modified Ono and Lindsey's microsurgical technique. Five transplantations were done for each combination. Postoperatively, donor heart beat was palpated everyday through the recipent's abdominal wall. Rejection was defined as complete cessation of donor heart beat. Result: The allogeneic heart grafts transplanted from PVG strain to ACI strain(PVG ACI) without DSBT were acutely rejected(mean survival 10.2 days). With pretransplant DSBT, the cardiac allografts in PVG ACI and LEW PVG combinations survived indefinitely(more than 100 days), those in ACI PVG combination survived 12 to 66 days(mean 31.8 days), those in PVG LEW survived 8 to 11 days(mean 10.0 days), and those in ACI LEW survived 7 to 9 days(mean 8.0 days). In brief, DSBT prior to heart transplantation was definitely effective in PVG ACI and LEW PVG combinations and moderately effective in ACI PVG combination, but not effective in PVG LEW and ACI LEW combinations. Conclusion: DSBT prior to heart transplantation showed variable effects, but might prolong cardiac allograft survival indefinitely in some donor recipient strain combinations. The mechanism of this effect should be further investigated.

• 기술혁신연구
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• 제24권1호
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• pp.85-111
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• 2016

본 연구에서는 온라인 쇼핑몰 상황에서 이전사업경험, 제품속성과 온라인 고객의견이 신제품 매출성과에 미친 영향을 살펴보았다. 인터넷 쇼핑몰에서 제품 성과에 대한 연구들은 선진국 온라인 쇼핑몰을 중심으로 고객들의 구전효과에 초점을 두고 연구를 진행해 왔으며 상대적으로 기업특성이나 제품속성에 대한 연구는 미흡하였다. 본 연구에서는 중국 인터넷 쇼핑몰에서 판매중인 총 407개 TV모델들을 대상으로 기업특성, 제품속성 및 온라인 고객의견이 제품 매출성과에 미친 영향을 살펴보았다. 기업특성에서는 이전TV제조업체들의 제품이 신규 진입기업들의 제품들보다 매출성과가 높았다. 제품속성에서는 경쟁제품 대비 초기 가격수준이 낮을수록 성과가 높으며 가격할인율이 높은 경우에는 오히려 매출성과가 낮았다. 전반적인 제품의 기술경쟁력 수준이 높을수록 판매성과가 높으며 신기능의 특성에 따라 매출성과에 미친 효과는 다르게 나타났다. 제품별 온라인 고객평가 의견수가 많을수록 해당 제품의 매출성과는 높은 것으로 나타난 반면, 온라인 고객평가 점수는 매출성과에 유의한 영향관계나 나타나지 않았다. 본 연구에서는 온라인 쇼핑몰 상황에서 신제품 매출성과 향상을 위한 이론적 실무적 의의를 제시하고 향후 연구과제들을 제시하였다.

• 한국수산과학회지
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• 제55권2호
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• pp.183-188
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• 2022

It is a difficult task to estimate parameters in even a simple stock assessment model such as a surplus production model, using only data about temporal catch-per-unit-effort (CPUE) (or survey index) and fishery yields. Such difficulty is exacerbated when time-varying parameters are treated as random effects (aka state variables). To overcome the difficulty, previous studies incorporated somewhat subjective assumptions (e.g., B₁=K) or informative priors of parameters. A key is how to build an objective joint prior of parameters, reducing subjectivity. Given the limited data on temporal CPUEs and fishery yields from 1999-2020 for common squid Todarodes pacificus, we built a joint prior of only two parameters, intrinsic growth rate (r) and carrying capacity (K), based on the resilience level of the population (Froese et al., 2017), and used a Bayesian state-space production assessment model. We used template model builder (TMB), a R package for implementing the assessment model, and estimating all parameters in the model. The predicted annual biomass was in the range of 0.76×10⁶ to 4.06×10⁶ MT, the estimated MSY was 0.13×10⁶ MT, the estimated r was 0.24, and the estimated K was 2.10×10⁶ MT.

• 한국자동차공학회논문집
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• 제18권1호
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• pp.66-73
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• 2010

This work was focused on the material parameter extraction for the isothermal cyclic deformation analysis for which Chaboche(Combined Nonlinear Isotropic and Kinematic Hardening) and Overlay(Multi Linear Hardening) models are normally used. In this study all the parameters were driven especially based on Overlay theories. A simple method is suggested to find out best material parameters for the cyclic deformation analysis prior to the isothermal LCF(Low Cycle Fatigue) analysis. The parameter extraction was done using 400 series stainless steel data which were published in the reference papers. For simple and quick review of the parameters extracted by suggested method, 1D FORTRAN program was developed, and this program could reduce the time for checking the material data tremendously. For the application to FE code ABAQUS user subroutine for the material models was developed by means of UMAT(User Material Subroutine), and the stabilized hysteresis loops obtained by the numerical analysis were in good harmony with test results.

• 디지털콘텐츠학회 논문지
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• 제13권3호
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• pp.325-334
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• 2012

드라마 프로그램 제작은 창작 영역에 속하는 것으로 간주되어 왔다. 따라서 드라마 프로그램의 품질 향상에 대한 시스템적 접근은 별로 시도되지 않았다. 본 연구의 목적은 KBS에서 제작되는 드라마 프로그램의 시청률을 방영 이전에 예측할 수 있는 통계적 계산모델을 제시하는 데 있다. 이를 위해 시청률에 영향을 미치는 요인들을 찾아내고 이들의 상호관계를 회귀분석 기법으로 밝혀내어 시청률 예측모델을 도출했다. 본 연구결과는 드라마 프로그램의 제작에 필요한 각 투입 요소들의 적정 규모를 산정하는 데 유용하게 활용될 수 있다.