• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제22권4호
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• pp.303-329
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• 2019

Intestinal failure (IF) is the critical reduction of the gut mass or its function below the minimum needed to absorb nutrients and fluids required for adequate growth in children. Severe IF requires parenteral nutrition (PN). Pediatric IF is most commonly due to congenital or neonatal intestinal diseases or malformations divided into 3 groups: 1) reduced intestinal length and consequently reduced absorptive surface, such as in short bowel syndrome (SBS) or extensive aganglionosis; 2) abnormal development of the intestinal mucosa such as congenital diseases of enterocyte development; 3) extensive motility dysfunction such as chronic intestinal pseudo-obstruction syndromes. The leading cause of IF in childhood is the SBS. In clinical practice the degree of IF may be indirectly measured by the level of PN required for normal or catch up growth. Other indicators such as serum citrulline have not proven to be highly reliable prognostic factors in children. The last decades have allowed the development of highly sophisticated nutrient solutions consisting of optimal combinations of macronutrients and micronutrients as well as guidelines, promoting PN as a safe and efficient feeding technique. However, IF that requires long-term PN may be associated with various complications including infections, growth failure, metabolic disorders, and bone disease. IF Associated Liver Disease may be a limiting factor. However, changes in the global management of IF pediatric patients, especially since the setup of intestinal rehabilitation centres did change the prognosis thus limiting "nutritional failure" which is considered as a major indication for intestinal transplantation (ITx) or combined liver-ITx.

• Coupled systems mechanics
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• 제7권1호
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• pp.1-4
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• 2018

This special issue contains selected papers first presented in a short format at the $3^{rd}$ International Conference ECCOMAS MSF 2017-Multiscale Computations for Solids and Fluids, organized in Slovenian capital Ljubljana, September 20-22, 2017.

• Coupled systems mechanics
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• 제9권1호
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• pp.1-4
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• 2020

This special issue contains selected papers first presented in a short format at the 4th International Conference ECCOMAS MSF 2019 - Multiscale Computations for Solids and Fluids, organized in Bosnian capital Sarajevo, September 18-20, 2019.

• Coupled systems mechanics
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• 제10권6호
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• pp.469-473
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• 2021

This special issue contains selected papers first presented in a short format at the 5th International Conference ECCOMAS MSF 2019-Multiscale Computations for Solids and Fluids, organized in Dalmatian capital Split, Croatia, June 30-July 2, 2021.

• Coupled systems mechanics
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• 제7권5호
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• pp.555-581
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• 2018

The moment-resistant steel frames are frequently used as a load-bearing structure of buildings. Global response of a moment-resistant frame structure strongly depends on connections behavior, which can significantly influence the response and load-bearing capacity of a steel frame structure. The analysis of a steel frame with included joints behavior is the main focus of this work. In particular, we analyze the behavior of two connection types through experimental tests, and we propose numerical beam model capable of representing connection behavior. The six experimental tests, under monotonic and cyclic loading, are performed for two different types of structural connections: end plate connection with an extended plate and end plate connection. The proposed damage-plasticity model of Reissner beam is able to capture both hardening and softening response under monotonic and cyclic loading. This model has 18 constitutive parameters, whose identification requires an elaborate procedure, which we illustrate in this work. We also present appropriate loading program and arrangement of measuring equipment, which is crucial for successful identification of constitutive parameters. Finally, throughout several practical examples, we illustrate that the steel structure connections are very important for correct prediction of the global steel frame structure response.

• Coupled systems mechanics
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• 제7권1호
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• pp.27-42
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• 2018

Behavior of soil is usually described with continuum type of failure models such as Mohr-Coulomb or Drucker-Prager model. The main advantage of these models is in a relatively simple and efficient way of predicting the main tendencies and overall behavior of soil in failure analysis of interest for engineering practice. However, the main shortcoming of these models is that they are not able to capture post-peak behavior of soil nor the corresponding failure modes under extreme loading. In this paper we will significantly improve on this state-of-the-art. In particular, we propose the use of a discrete beam lattice model to provide a sharp prediction of inelastic response and failure mechanisms in coupled soil-foundation systems. In the discrete beam lattice model used in this paper, soil is meshed with one-dimensional Timoshenko beam finite elements with embedded strong discontinuities in axial and transverse direction capable of representing crack propagation in mode I and mode II. Mode I relates to crack opening, and mode II relates to crack sliding. To take into account material heterogeneities, we determine fracture limits for each Timoshenko beam with Gaussian random distribution. We compare the results obtained using the discrete beam lattice model against those obtained using the modified three-surface elasto-plastic cap model.

• Coupled systems mechanics
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• 제7권2호
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• pp.233-254
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• 2018

In order to reduce the dependency on fossil fuels, a policy to increase the production capacity of wind turbine is set up. This can be achieved with increasing the dimensions of offshore wind turbine blades. However, this increase in size implies serious problems of stability and durability. Considering the cost of large turbines and financial consequences of their premature failure, it is imperative to carry out numerical simulations over long periods. Here, an energy-conserving time-stepping scheme is proposed in order to ensure the satisfying computation of long-term response. The proposed scheme is implemented for three-dimensional solid based on Biot strain measures, which is used for modeling flexible blades. The simulations are performed at full spatial scale. For reliable design process, the wind loads should be represented as realistically as possible, including the fluid-structure interaction (FSI) dynamic effects on wind turbine blades. However, full-scale 3D FSI simulations for long-term wind loading remain of prohibitive computation cost. Thus, the model to quantify the wind loads proposed here is a simple, but not too simple to be representative for preliminary design studies.

• 식물병연구
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• 제20권2호
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• pp.79-86
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• 2014

화훼 수출 검역에서 기존 메틸브로마이드 훈증보다 경제적이고 친환경적이며 안전한 대안으로서 감마선 융복합 처리 기술을 백합 잎마름병 방제에 적용하였다. 감마선 융복합 처리는 200 Gy 감마선과 이염화이소시안산나트륨(NaDCC) 은나노 입자(NSS)의 화학대체제를 시베리아, 르네부, 소르본느 품종의 절화 백합이 담긴 수출포장용 종이상자에 총 6회로 실시하였다. 감마선 조사 8일 후 백합 잎과 꽃잎에서 측정한 발병율(disease incidence)과 발병도(disease severity)로 분석 결과, 감마선은 소르본느 잎에서 발병도를 약 13-25% 감소시킨 반면, 르네부 잎에서는 발병도를 2-5% 증가시켰다. 화학대체제 처리와 무처리를 비교한 결과 절화 백합 수출현장에서 화학대체제의 잎마름병 발병 억제 효과를 기대할 수 없었다. 한편, 조사 12일 후 감마선 처리 유무에 따른 백합 잎의 엽록소 함량 비교 결과 감마선에 의해 통계적으로 유의하게 감소하였고, 시베리아와 소르본느 꽃의 만개 기간을 0.4-1.2일 연장시켰다. 또한 감마선이 조사된 절화는 화병에서 무처리에 비해 마름이 발생하여 생중량 감소가 뚜렷하였다. 한편, 1과 2 kGy 고선량 감마선은 백합 꽃봉오리 끝 부분을 짙은 갈색으로 변색시키거나 꽃봉오리 목 부분의 꺽임, 봉오리가 개화하지 못하게 하는 등 마름 이외에도 감마선 과도에 의한 품질저해 피해가 나타났다.

• 원예과학기술지
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• 제28권3호
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• pp.363-369
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• 2010

조직배양구를 순화시키기 위하여 상토에 정식을 할 때 순화율을 높이고 구 비대에 적합한 재식밀도와 깊이를 구명하고자 시험을 수행되었다. 오리엔탈나리 대표 품종들인 '시베리아'와 '솔본느' 조직배양구의 효과적인 순화를 위한 재식 밀도를 200, 400, 600, 800, 1,000구/$m^2$ 단위로 하였으며, 재식깊이 시험을 위해 상토의 복토를 1, 3, 6, 9, 12cm로 나누어 정식하였다. 오리엔탈나리 '시베리아'의 경우 $m^2$ 당 400구 재식시 생존율 87.3%, 구주 6.4cm, 구중 8.3g, 구주 6cm 이상 비율 61.6%로 가장 적합하였다. '솔본느'의 경우도 400구/$m^2$에서 생존율 88.8%, 구주 5.0cm, 구중 7.1g 으로 가장 효율적인 것으로 생각되었다. 오리엔탈나리 '시베리아'와 '솔본느' 조직배양구의 순화를 위한 적정 재식깊이는 '시베리아'의 경우 지표면에서 3cm 재식구가 생존율 77.8%, 구주 5.9cm, 구중 7.9g, 구주 6cm이상 비율 47.2-51.0%로 가장 양호하였고, '솔본느'의 경우도 3cm 재식구에서 생존율 87.1%, 구주 5.1cm, 구중 6.5g로 가장 양호하였다.

• Coupled systems mechanics
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• 제5권2호
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• pp.145-156
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• 2016

An efficient and general numerical strategy for fluid-structure interaction problems is presented where either the fluid or the structure part are represented by nonlinear models. This partitioned strategy is implemented under the form of code coupling that allows to (re)-use previous made developments in a more general multi-physics context. This strategy and its numerical implementation is verified on classical fluid-structure interaction benchmarks, and then applied to the impact of tsunamis waves on submerged structures.