• Computers and Concrete
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• v.1 no.2
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• pp.169-188
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• 2004

A coupled damage-viscoplasticity model is presented for the analysis of localisation and size effects. On one hand, viscosity helps to avoid mesh sensitivity because of the introduction of a length scale in the model and, on the other hand, enables to represent size effects. Size effects were analysed by means of three-point bending tests. Correlation between the fracture energy parameter measured experimentally and the density fracture energy modelling parameter is discussed. It has been shown that the dependence of nominal strength and fracture energy on size is determined by the ligament length in comparison with the width of the fracture process zone.

• Molecules and Cells
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• v.37 no.7
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• pp.526-531
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• 2014

Human PARP family consists of 17 members of which PARP-1 is a prominent member and plays a key role in DNA repair pathways. It has an N-terminal DNA-binding domain (DBD) encompassing the nuclear localisation signal (NLS), central automodification domain and C-terminal catalytic domain. PARP-1 accounts for majority of poly-(ADP-ribose) polymer synthesis that upon binding to numerous proteins including PARP itself modulates their activity. Reduced PARP-1 activity in ageing human samples and its deficiency leading to telomere shortening has been reported. Hence for cell survival, maintenance of genomic integrity and longevity presence of intact PARP-1 in the nucleus is paramount. Although localisation of full-length and truncated PARP-1 in PARP-1 proficient cells is well documented, subcellular distribution of PARP-1 fragments in the absence of endogenous PARP-1 is not known. Here we report the differential localisation of PARP-1 Nterminal fragment encompassing NLS in PARP-$1^{+/+}$ and PARP-$1^{-/-}$ mouse embryo fibroblasts by live imaging of cells transiently expressing EGFP tagged fragment. In PARP-$1^{+/+}$ cells the fragment localises to the nuclei presenting a granular pattern. Furthermore, it is densely packaged in the midsections of the nucleus. In contrast, the fragment localises exclusively to the cytoplasm in PARP-$1^{-/-}$ cells. Flourescence intensity analysis further confirmed this observation indicating that the N-terminal fragment requires endogenous PARP-1 for its nuclear transport. Our study illustrates the trafficking role of PARP-1 independently of its enzymatic activity and highlights the possibility that full-length PARP-1 may play a key role in the nuclear transport of its siblings and other molecules.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.05a
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• pp.49-50
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• 2004

• Journal of Electrical Engineering and Technology
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• v.4 no.2
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• pp.168-174
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• 2009

An application of wavelet analysis to power system transient generated signals is presented in this paper. With the time-frequency localisation characteristics embedded in wavelets, the time and frequency information of a waveform can be presented as a visualised scheme. This feature is very important for non-stationary signals analysis such as the ones generated from power system disturbances. Unlike the Fourier transform, the wavelet transform approach is more efficient in monitoring fault signals as time varies. For time intervals where the function changes rapidly, this method can zoom in on the area of interest for better visualisation of signal characteristics.

• Smart Structures and Systems
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• v.21 no.6
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• pp.751-759
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• 2018

Glass fibre reinforced polymers (GFRP) are widely exploited in many industrial branches. Due to this Structural Health Monitoring systems containing embedded fibre optics sensors are applied. One of the problems that can influence on composite element durability is water contamination that can be introduced into material structure during manufacturing. Such inclusion can be a damage origin significantly decreasing mechanical properties of an element. A non-destructive method that can be applied for inspection of an internal structure of elements is THz spectroscopy. It can be used for identifications of material discontinuities that results in changes of absorption, refractive index or scattering of propagating THz waves. The limitations of THz propagation through water makes this technique a promising solution for detection of a water inclusion. The paper presents an application of THz spectroscopy for detection and localisation of a water drop inclusion embedded in a GFRP material between two fibre optics with fibre Bragg grating sensors. The proposed filtering method allowed to determine a 3D shape of the water drop.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.464-473
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• 2006

This paper summarises theoretical and experimental work on the feedback control of sound radiation from honeycomb panels using piezoceramic actuators. It is motivated by the problem of sound transmission in aircraft, specifically the active control of trim panels. Trim panels are generally honeycomb structures designed to meet the design requirement of low weight and high stiffness. They are resiliently-mounted to the fuselage for the passive reduction of noise transmission. Local coupling of the closely-spaced sensor and actuator was observed experimentally and modelled using a single degree of freedom system. The effect of the local coupling was to roll-off the response between the actuator and sensor at high frequencies, so that a feedback control system can have high gain margins. Unfortunately, only relatively poor global performance is then achieved because of localisation of reduction around the actuator. This localisation prompts the investigation of a multichannel active control system. Globalised reduction was predicted using a model of 12 channel direct velocity feedback control. The multichannel system, however, does not appear to yield a significant improvement in the performance because of decreased gain margin.

• Interaction and multiscale mechanics
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• v.1 no.1
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• pp.143-156
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• 2008

Elliptical tubes may buckle in an elastic local buckling failure mode under uniform compression. Previous analyses of the local buckling of these members have assumed that the cross-section is hollow, but it is well-known that the local buckling capacity of thin-walled closed sections may be increased by filling them with a rigid medium such as concrete. In many applications, the medium many not necessarily be rigid, and the infill can be considered to be an elastic material which interacts with the buckling of the elliptical tube that surrounds it. This paper uses an energy-based technique to model the buckling of a thin-walled elliptical tube containing an elastic infill, which elucidates the physics of the buckling phenomenon from an engineering mechanics basis, in deference to a less generic finite element approach to the buckling problem. It makes use of the observation that the local buckling in an elliptical tube is localised with respect to the contour of the ellipse in its cross-section, with the localisation being at the region of lowest curvature. The formulation in the paper is algebraic and it leads to solutions that can be determined by implementing simple numerical solution techniques. A further extension of this formulation to a stiffness approach with multiple degrees of buckling freedom is described, and it is shown that using the simple one degree of freedom representation is sufficiently accurate for determining the elastic local buckling coefficient.

• Smart Structures and Systems
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• v.20 no.6
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• pp.669-682
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• 2017

The normalised version of bispectrum, the so-called bicoherence, has often proved a reliable method of damage detection on engineering applications. Indeed, higher-order spectral analysis (HOSA) has the advantage of being able to detect non-linearity in the structural dynamic response while being insensitive to ambient vibrations. Skewness in the response may be easily spotted and related to damage conditions, as the majority of common faults and cracks shows bilinear effects. The present study tries to extend the application of HOSA to damage localisation, resorting to a neural network based classification algorithm. In order to validate the approach, a non-linear finite element model of a 4-meters-long cantilever beam has been built. This model could be seen as a first generic concept of more complex structural systems, such as aircraft wings, wind turbine blades, etc. The main aim of the study is to train a Neural Network (NN) able to classify different damage locations, when fed with bispectra. These are computed using the dynamic response of the FE nonlinear model to random noise excitation.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.3
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• pp.87-96
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• 2012

This study aimed at empirically identifying how the cultural phenomena of localisation and attachment are implemented through Mohyeonjeong and Supodae at Gajo-myeon, Geochang-gun, Gyeongnam. 'Daehakdong', the name of the place where the Mohyeon-jeong and Supodae is located, has a meaning of the place where Geong-Pil Kim(金宏弼) the Hanhwondang(寒暄堂), one of the 5 eastern sages, and Yeo-Chang Jeong(鄭汝昌) the Ildu tought Neo-Confucianism. In addition, in case of Mt. Odo(1,134m) embracing the garden, the meaning of Odo is the five virtues in Confucianism, so we can see that Confucianism was strong in that area. The meaning of 'Mohyeon(慕賢)', "missing and thinking of sages", reflects the emotion of attachment to the place where people pay a tribute to the memory of Seon-Saeng Yang the Hwondu, one of the 5 eastern sages and the creator of Neo-Confucianism in Kyeongnam, and Suk-Ryang Choi(崔淑梁) the ancestors Pyeongchon. In addition, Odojae(吾道齋), Kijeok monument to pay a tribute to the memory of Pyeongchon, the persimmon tree symbolizing Hanhwondang, and Jidongam(志同巖) standing in front of Mohyeon pavillion represent the united wills of the above 3 people to show their Dohak(道學) spirit by practicing it, and also a reiterated expression of attachment to the place. 'Hwonduyangseonsaeng janggujiso' and 'Pyeongchonchoigong ganghakjiso(坪村崔公講學地所)' engraved on the rock of Myeongso Supodae where they gave a lecture of Neo-Confucianism to local Confucianists for many years and enjoyed nature make us to identify the intrinsic meaning of the location that was inherited in the memory of people. Along with this, most of the content of poetry, restoration records, and Sangryang articles are filled with the content reminding of the historical meaning and origin of Mohyeon-jeong and Supodae, so we can see from this that the place had the spatial meaning of Jangsujiso(藏修之所), 'the place of lecturing and communicating' and respecting ancient sages. This spatial tradition is the result of positive attachment to the place, and Mohyeon-jeong and Supodae is the place where the attachment to the place was made spontaneously througth the localisation. To sum it up, Mohyeon-jeong and Supodae was the place of attachment where one paid a tribute to the memory of ancient sages, and Mohyeonjeong and Supodae rocks were the representative examples of the localisation to show the meaning of the place by implication. Studying the process of attachment and localisation of the place does not only enable us to infer the genuine form of the traditional memorial space and park, but also to reproduce the place with the modern concept.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.231-236
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• 1999

금번 연구는 공간 음상 정위에 직면하는 주된 문제점인 음색왜곡과 음질저하의 영향 인자들과 개선방안을 고찰한다. 측정 머리전달함수로부터 청각기관의 공간 음상에 대만 인지양적 특성치 (양귀 음압레벨 차이 ILD와 음압 도달시간 차비 ITD)를 추정하는 새로운 방법의 제안, 총간 음상정위 특성치의 새로운 DB구축, 그러고 이를 이용한 공간 음상 정위 구현방법의 새로운 방안을 소개한다. 그리고, 제안된 공간 음상 구현 기법은 음색 왜곡 및 음질저하를 최소화할 뿐 아니라 구현 방법의 간결성 때문에 제품화로 직접 적용할 수 있는 장점을 제공할 수 있음을 본 논문에서 보인다.