• 한국실천공학교육학회논문지
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• 제3권1호
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• pp.15-24
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• 2011

녹색에너지의 모델링과 시뮬레이션은 연구하고자 하는 시스템의 형태에 따라 크게 의존한다. 모델링과 시뮬레이션의 주요내용은 반도체 물리(태양전지), 전기모터/발전기(풍력터빈), 전형적인 제어전략에 의한 전력전자(계통연계)등 매우 다양하다. 이들 기술들을 정확하게 모델링하는 것은 다양한 시뮬레이션 기술과 많은 모델들을 필요로 한다. 시뮬레이션을 더욱 정확하게 혹은 상세하게 하기 위해서 모델링은 특정레벨 즉, 시스템, 회로, 요소 레벨 등으로 수행하여야 한다. 다양한 레벨의 조합은 모델 방정식과 이용 가능한 매개변수들에 대한 전체적인 모델의 유용성을 크게 개선할 수 있다.

• 대한의용생체공학회:의공학회지
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• 제36권6호
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• pp.276-282
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• 2015

Recently, during the multi-level fusion with pedicle screws, interspinous spacer are sometimes substituted for the most superior level of the fusion in an attempt to reduce the number of fusion level and likelihood of degeneration process at the adjacent level. In this study, a finite element (FE) study was performed to assess biomechanical efficacies of the interspinous spacer combined with posterior lumbar fusion with a previously-validated 3-dimensional FE model of the intact lumbar spine (L1-S1). The post-operative models were made by modifying the intact model to simulate the implantation of interspinous spacer and pedicle screws at the L3-4 and L4-5. Four different configurations of the post-op model were considered: (1) a normal spinal model; (2) Type 1, one-level fusion using posterior pedicle screws at the L4-5; (3) Type 2, two-level (L3-5) fusion; (4) Type 3, Type 1 plus Coflex$^{TM}$ at the L3-4. hybrid protocol (intact: 10 Nm) with a compressive follower load of 400N were used to flex, extend, axially rotate and laterally bend the FE model. As compared to the intact model, Type 2 showed the greatest increase in Range of motion (ROM) at the adjacent level (L2-3), followed Type 3, and Type 1 depending on the loading type. At L3-4, ROM of Type 2 was reduced by 34~56% regardless of loading mode, as compared to decrease of 55% in Type 3 only in extension. In case of normal bone strength model (Type 3_Normal), PVMS at the process and the pedicle remained less than 20% of their yield strengths regardless of loading, except in extension (about 35%). However, for the osteoporotic model (Type 3_Osteoporotic), it reached up to 56% in extension indicating increased susceptibility to fracture. This study suggested that substitution of the superior level fusion with the interspinous spacer in multi-level fusion may be able to offer similar biomechanical outcome and stability while reducing likelihood of adjacent level degeneration.

• The Journal of Asian Finance, Economics and Business
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• 제7권11호
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• pp.893-904
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• 2020

The study examines the relationship between credit risk and operational risk (understanding of risk management, risk identification, risk assessment and control, and risk monitoring) on risk management practices followed by private and public sector commercial banks. The cross-sectional data method was used to check the impact of risk management practices. Data was collected from the bank employees and a total of 284 respondents were finally selected for further analysis. Measurement Invariance of Composite Models analysis is used to test the quality of the measurement model for sub-samples, and multi-group analysis is used for path analysis in sub-sample through PLS-SEM. The findings of the study as the total sample show that both types of banks are managing adequate and significant risk management practices. On the other hand, sub-groups' results show private sector banks are more momentous than public sector banks. Risk identification is significantly different at the sub-group level, which shows public sector banks are more concentrating on this type of risk. Understanding of risk management has no significant effect on both types of banks and risk assessment & control for public sector banks, and there is a difference in the risk management practices among private and public sector commercial banks.

• 농촌계획
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• 제9권4호
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• pp.43-51
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• 2003

This study aims to integrate the simulation models for rural settlement planning (SimRusep) in the district level (Myon) area of rural counties. The SimRusep, which has two modules of key villages selection and spatial planning for the selected villages, consists of four sub-models such as the spatial location-allocation model of center villages (SLAMCV), the potential centrality evaluation model (PCEM), the land use planning model (LUPM), and the 3-dimensional spatial planning modeller (3DSPLAM). Basically, map data of the integrated system which can be operated on the UNIX environment is inputted and treated using GIS (ARC/INFO) and then its village planning results is graphically presented on the AutoCAD. In order to verify the practical applicabilities of the SimRusep, an administrative area, Ucheon-myun, HoengSung-gun, KangWon-do, was selected as a case study area. It was well operated in the strategic application trials considering application of each sub-model in the study area. The operation results of the SimRusep showed the possibilities of realtime simulation from the selection of key village to its final stereoscopic presentation of planned results. Alternative village plan proposals can be swiftly drafted, which means very practical support for decision making process and public participation.

• 간호행정학회지
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• 제23권2호
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• pp.111-117
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• 2017

Getting evidence in to practice tends to focus on strategies, theories and studies that aim to close the gap between research knowledge and clinical practice. The evidence to practice gap is more about systems than individual clinician decision making. The absence of evidence for administration and management in the organization of healthcare is persistent. Teaching nurses and providing evidence as the solution to evidence-based healthcare is no longer axiomatic. Previous studies have concluded that unit level strategies integrate multi-professional teams with organizational needs and priorities. This 'best fit' approach that characterizes how healthcare is structured and delivered. The published literature shows that increased readiness for change is aligned with integrated approaches informed by conceptual models. The Joanna Briggs Collaboration is the largest global collaboration to integrate evidence within a theory informed model that brings together academic centres, hospitals and health systems for evidence synthesis, transfer and implementation. The best approaches to implementation are tailored to local culture and context, benchmark against international evidence, combine a theory informed model and stakeholder perspectives to improve the structure and processes of health care policy and practice.

• Earthquakes and Structures
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• 제7권6호
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• pp.1223-1240
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• 2014

Seismic isolation has been established as an effective earthquake-resistant design method and the lead rubber bearings (LRBs) are among the most commonly used seismic isolation systems. In the scientific literature, a sharp bilinear model is often used for capturing the hysteretic behaviour of the LRBs in the analysis of seismically isolated structures, although the actual behaviour of the LRBs can be more accurately represented utilizing smoothed plasticity, as captured by the Bouc-Wen model. Discrepancies between these two models are quantified in terms of the computed peak relative displacements at the isolation level, as well as the peak inter-storey deflections and the absolute top-floor accelerations, for the case of base-isolated buildings modelled as multi degree-of-freedom systems. Numerical simulations under pulse-like ground motions have been performed to assess the effect of non-linear parameters of the seismic isolation system and characteristics of both the superstructure and the earthquake excitation, on the accuracy of the computed peak structural responses. Through parametric analyses, this paper assesses potential inaccuracies of the computed peak seismic response when the sharp bilinear model is employed for modelling the LRBs instead of the more accurate and smoother Bouc-Wen model.

• Advances in materials Research
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• 제9권3호
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• pp.189-202
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• 2020

The objective of the present work is to investigate the effect of cutting parameters (Vc, fz and ap) on tool life and the level of vibrations velocity in the machined part during face milling operation of hardened AISI 52100 steel. Dry-face milling has been achieved in the annealed (28 HRc) and quenched (55 HRc) conditions using multi-layer coating micro-grain carbide inserts. Statistical analysis based on the Response surface methodology (RSM) and ANOVA analysis have been conducted through a plan of experiments methodology using a reduced Taguchi table (L9) in order to obtain engineering models for tool life and vibration velocity in the workpiece for both heat treatment conditions. The results show that the cutting speed has a dominant influence on tool life for both soft and hard part. Cutting speed and feed per tooth is the most significant parameters for vibration levels. Comparing the experimental values with those predicted by the developed engineering models of tool life and levels of vibrations velocity, a good correlation has been obtained (between 97% and 99%) in annealed and hard conditions.

• 한국병원경영학회지
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• 제25권3호
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• pp.53-66
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• 2020

This study is aimed at investigated and compared the differences in the affect of hospital specialization according to hospital size using claims data of the Health Insurance and Review Assessment National Inpatient Sample in 2018 for diseases of the musculoskeletal system and connective tissue. To this end, we used multivariate hierarchical linear models(a.k.a., multi-level models) using two-tier data from 106,599 patients discharged after diseases of the musculoskeletal system and connective tissue from 734 hospitals. Multivariate results indicate that patients who were discharged with diseases of the musculoskeletal system and connective tissue from specialized hospitals with 200 beds or less stayed shorter and paid less inpatient charge than those who were discharged from less specialized hospitals. But for hospitals with 201-300 beds, no positive impact relationship was found between hospital specialization and operational performance. This finding may be limited evidence that the affect of a hospital's specialization strategy may vary depending on the size of the hospital. We discussed several managerial and health policy implications below.

• 대한산업공학회지
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• 제28권3호
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• pp.274-282
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• 2002

This paper discusses a multi-dimensional analysis for Customer Relationship Management (CRM). For this, We propose a decision-making methodology which employs three analysis models. The first model is a three-dimension positioning map to derive a strategy which achieves the Process Value Line (PVL). The second model is the web-shape analysis model to visibly understand the individual based on the customer CSI (Customer Satisfactory Index) data. The third model which supports the web-shape analysis model, is the relative satisfactory analysis model. It considers a satisfaction level after purchasing against before purchasing. Then we perform overall analysis based on the three analysis models to provide marketing strategies to decision makers.

• Earthquakes and Structures
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• 제7권1호
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• pp.83-99
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• 2014

This study is devoted to estimate higher-mode effects for multi-story structures with considering soil-structure interaction subjected to decomposed parts of near-fault ground motions. The soil beneath the super-structure is simulated based on the Cone model concept. Two-dimensional structural models of 5, 15, and 25-story shear buildings are idealized by using nonlinear stick models. The ratio of base shears for the soil-MDOF structure system to those obtained from the equivalent soil-SDOF structure system is selected as an estimator to quantify the higher-mode effects. The results demonstrate that the trend of higher-mode effects is regular for pulse component and has a descending variation with respect to the pulse period, whereas an erratic pattern is obtained for high-frequency component. Moreover, the effect of pulse component on higher modes is more significant than high-frequency part for very short-period pulses and as the pulse period increases this phenomenon becomes vice-versa. SSI mechanism increases the higher-mode effects for both pulse and high-frequency components and slenderizing the super-structure amplifies such effects. Furthermore, for low story ductility ranges, increasing nonlinearity level leads to intensify the higher-mode effects; however, for high story ductility, such effects mitigates.