• Computers and Concrete
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• 제13권3호
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• pp.389-409
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• 2014

Precast hollow core slabs (HCS) are technically advanced products in the precast concrete industry, widely used in the last years due to their versatility, their multipurpose potential and their low cost. Using three dimensional FEM (Finite Element Method) elements, this study focuses on the stresses induced by the prestressing of steel. In particular the investigation of the spalling crack formation that takes place during prestressing is carried out, since it is important to assure the appropriate necessary margins concerning such stresses. In fact, spalling cracks may spread rapidly towards the web, leading to the detachment of the lower part of the slab. A parametric study takes place, capable of evaluating the influence of the tendon position and of the web width on the spalling stress. Consequently, after an extensive literature review on the topic of soft computing, an optimization of the HCS is performed by means of Genetic Algorithms coupled with 3-D FEM models.

• Interaction and multiscale mechanics
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• 제1권4호
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• pp.449-465
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• 2008

In this paper a general approach for studying the motion of a cantilever beam interacting with a 2D fluid flow is presented. The fluid is solved by a general purpose commercial computational fluid dynamics (CFD) package (FLUENT 6.2), while the structure is managed by means of a dedicated finite element method solver, coded in FLUENT as a user-defined function (UDF). A weak fluid structure interaction coupling scheme is adopted exchanging information at the end of each time step. An arbitrary cantilever beam can be introduced in the CFD mesh with its wetted boundaries specified; the cantilever can also interact with specified rigid and flexible walls through use of a non-linear contact algorithm. After a brief review of relevant scientific contributions, some test cases and application examples are presented.

• International Journal of Aeronautical and Space Sciences
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• 제12권4호
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• pp.331-345
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• 2011

In this paper, a visco-hysteretic vibration absorber (VA) is proposed to increase the flutter speed of an airfoil and enhance damping in the pre- and post-flutter regimes. The passive system consists of a parallel arrangement of a dashpot and a rateindependent hysteretic element, represented by the Bouc-Wen differential model. The equations of motion are obtained and various tools of linear and nonlinear dynamics are employed to study the effects of the visco-hysteretic VA in the pre- and postflutter ranges.

• 가족자원경영과 정책
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• 제14권2호
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• pp.79-90
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• 2010

The purpose of this study is to review the research trends of family life planning in the Journal of Korean Rome Economics Association, the Journal of Korean Rome Management Association and the Journal of Korean Family Resource Management Association. For this purpose, 132 studies were analyzed according to the theory of family life planning, the state of family life planning, the diagnosis of present, the establishment of future and the practice of family life planning. At this time, we feel that it is meaningful to review the research of family life planning and to take a look at its possible future prospects. This study also provides the information necessary to implement and integrate its positive results into Family Life Education.

• 산업기술연구
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• 제29권A호
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• pp.27-36
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• 2009

Reliability plays a pivotal role in products safety and quality. DoD RIAC recently developed a new reliability prediction methodology, $217Plus^{TM}$, for electronic systems. It officially replaces the well-known MIL-HDBK-217 and is expected to be widely used. Although theoretic study about $217Plus^{TM}$ and its application towards field systems seem to be attractive, it is also desirable to understand the general background of its development. In this paper, we performed a historical review of the arenas related to reliability prediction. Due to the vast of materials, our scope was limited to the development of $217Plus^{TM}$. We first reviewed Rome Laboratory and RIAC. We then explained the development course of reliability methods, MIL-HDBK-217, PRISM, and 217-Plus. This review will form not only a good understanding of the methodology but a basis for future study. We conclude this study with provision of future research areas.

• Earthquakes and Structures
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• 제9권3호
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• pp.503-539
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• 2015

A new constitutive model for the representation of the seismic behaviour of steel bars including hardening phenomena is presented. The model takes into account relative slip between bars and concrete, necessary for the estimation of the structural behaviour of r.c. elements and of the level of strain induced by earthquakes on bars. The present work provides the analytical formulation of the post-yielding behaviour of reinforcements, resulting in a continuous axial stress-slip relationship to be implemented in engineering software. The efficacy of the model is proved through the application to a cantilever column, for whose bars the constitutive law is derived.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.127.1-127
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• 2003

• 대한한방내과학회지
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• 제36권3호
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• pp.308-322
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• 2015

Objectives: Whether there exists a distinct pathogenesis in subgroups of functional dyspepsia (FD), the classification of epigastric pain syndrome (EPS), and postprandial distress syndrome (PDS) remains controversial. We aimed to investigate the number of fungiform papillae (FP) in the subgroups of FD and its correlation with the severity of dyspepsia symptoms and spleen qi deficiency. Methods: Patients with FD were enrolled from August to November 2014. All patients were evaluated using a questionnaire and divided into 2 groups according to the Rome III criteria for FD. The severity of dyspepsia symptoms and spleen qi deficiency were separately assessed by Nepean Dyspepsia Index-Korean (NDI-K) version and Spleen qi deficiency questionnaire (SQDQ). The number of FP was measured on the anterior part of tongue, within an area of 9 mm ², using a digital cam Results: The NDI-K score, SQDQ score, and number of FP in the EPS group were significantly greater than those in the PDS group. Also, the EPS group had more patients diagnosed with spleen qi deficiency. The number of FP showed a significant positive correlation with epigastric pain and burning. Furthermore, the number of FP was significantly associated with the score of some items in NDI-K and SQDQ, even though not with the total score. Conclusions: Thus, measurement of the number of FP could be a new evaluation indicator for allocation into FD subtypes and to investigate the severity of dyspepsia symptoms and spleen Qi deficiency reflecting visceral hypersensitivity.

• Structural Engineering and Mechanics
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• 제64권6권
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• pp.765-781
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• 2017

The out-of-plane response of infill walls has recently gained a growing attention and has been recognised fundamental in the damage assessment of reinforced concrete and steel framed buildings subjected to seismic loads. The observation of damage after earthquakes highlighted that out-of-plane collapse of masonry infills may occur even during seismic events of low or moderate intensity, causing both casualty risks and unfavourable situations affecting the overall structural response. Even though studies concerning the out-of-plane behaviour of infills are not as many as those focused on the in-plane response, in the last decades, a substantial number of researches have been carried out on the out-of-plane behaviour of infills. In this study, the out-of-plane response is investigated considering different aspects. First, damages observed after past earthquakes are examined, with the aim of identifying the main parameters involved and the most critical configurations. Secondly, the response recorded in about 150 experimental tests is deeply examined, focusing on the influence of geometrical characteristics, boundary conditions, prior in-plane damage, presence of reinforcing elements and openings. Finally, different theoretical capacity models and code provisions are discussed and compared, giving specific attention to those based on the arching theory. The reliability of some of these models is herein tested with reference to experimental results. The comparison between analytically predicted and experimental values allows to appreciate the extent of approximation of such methods.

• 대한한방소아과학회지
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• 제31권3호
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• pp.1-13
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• 2017

Objectives The purpose of this study is to investigate how irritable bowel syndrome (IBS) affects fatigue scales and eating habits in children and adolescents using Rome IV criteria. Methods Questionnaires and The $PedsQL^{TM}$ Multidimensional Fatigue Scale (MFS) have been given to 211 children and adolescents aged 8 to 18 years old who were admitted to ${\bigcirc}{\bigcirc}$ university Korean medicine hospital pediatric departments, from 29th, July, 2016 to 12th, August, 2016 to evaluate their eating habits and fatigue. Additionally, PASW statistics 18.0 were used to analyze influence of irritable bowel syndrome on eating habits and fatigue in children and adolescents by using chi-square test, independent t-test and linear regression. Results In total of 211 subjects, 29 (13.7%) were diagnosed with IBS according to the Rome IV criteria. 1. There was a statistically significant difference (p<0.05) between IBS group and non-IBS group on a specific question in the eating habit questionnaire: the amount of sugar intake and the prevalence of IBS. 2. There was a statistically significant difference in general fatigue and cognitive fatigue categories when comparing the MFS subscores according to the prevalence of IBS. Conclusions Considering patients eating habits and fatigue is a necessary process for the successful treatment of irritable bowel syndrome. Korean medicine that maximizes quality of life while minimizing the potential risks to the patients of gastrointestinal disease should also include administrative interventions that may be helpful in the daily life of IBS patients.