• Journal of Korean Society of Steel Construction
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• v.17 no.2 s.75
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• pp.173-181
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• 2005

This study deals with a method to identify damages of free vibrating thin plate structures using the combined finite element method (FEM) and the advanced uniform micro-genetic algorithm.To solve the inverse problem using the combined method, this study uses several natural frequencies instead of mode shapes in a structure as the measured data. The technique described in this paper allows us not only to detect the damaged elements but also to find their numbers, locations, and the extent of damage.To demonstrate the feasibility of the proposed method, the algorithm is applied to a free vibrating steel thin plate structures with arbitrary damages. From the standpoint of computation efficiency, the proposed method in this study has advantages when compared with the existing simple genetic algorithms. The numerical examples demonstrate that the method using micro-genetic algorithms can possibly detect correctly the damages of thin plates from only several natural frequencies instead of their natural modes.

• Journal of the Korean Institute of Oriental Medical Informatics
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• v.16 no.2
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• pp.163-187
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• 2010

The concept of latent-gi(伏氣) was first mentioned in Yellow Emperor's Canon of Internal Medicine. For example, Elementary Questions states, "Damage by cold in winter necessarily engenders warm disease in the spring." Zhang Zhong-Jing of Han Dynasty in On Cold Damage and Miscellaneous Diseases mentions warm disease, stating, for example, "Greater yang disease with heat effusion and cough and without aversion to cold is warm disease. If sweating is applied, and there is generalized heat, this is wind warmth." However, the concept of warm disease was not central to his systematic presentation of externally contracted disease which placed the emphasis on wind and cold as the major causes of these diseases. Zhang Zhong-Jing's theories centuries after in the Sung Dynasty were to become the focus of the cold damage school, whereas the concept of warm disease was to become the focus of a rival school, the warm disease school. In the Sui-Tang Period, The Origin and Indications of Disease mentions warm diseases, their causes, patterns, and major principles of treatment. Successive generations of doctors wrote about warm disease, and in the Ming Dynasty writings on the subject become more prolific. This development is attributable on the one hand to the opening up of the south of China where febrile diseases tended to be of a different nature than in the north, and on the other to pestilences arising as a result of wars. In this period, Wu You-Xing in On Warm Epidemics explained in detail the laws governing the origin, development and pattern identification of warm epidemics. Notably, he posed the etiological notion of a contagious perverse gi.

• Molecular & Cellular Toxicology
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• v.3 no.4
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• pp.246-253
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• 2007

Doxorubicin and daunorubicin are excellent chemotherapeutic agents utilized for several types of cancer but the irreversible cardiac damage is the major limitation for its use. The biochemical mechanisms of doxorubicin- and daunorubicin- induced cardiotoxicity remain unclear. There are many reports on toxicity of doxorubicin and doxorubicin in cardiomyocytes, but effects in cardiovascular system by these drugs are almost not reported. In this study, we investigated gene expression profiles in human umbilical vein endothelial cells (HUVECs) to better understand the causes of doxorubicin and doxorubicininduced cardiovascular toxicity and to identify differentially expressed genes (DEGs). Through the clustering analysis of gene expression profiles, we identified 124 up-regulated common genes and 298 down-regulated common genes changed by more than 1.5-fold by all two cardiac toxicants. HUVECs responded to doxorubicin and doxorubicin damage by increasing levels of apoptosis, oxidative stress, EGF and lipid metabolism related genes. By clustering analysis, we identified some genes as potential markers on apoptosis effects of doxorubicin and doxorubicin. Six genes of these, BBC3, APLP1, FAS, TP53INP, BIRC5 and DAPK were the most significantly affected by doxorubicin and doxorubicin. Thus, this study suggests that these differentially expressed genes may play an important role in the cardiovascular toxic effects and have significant potential as novel biomarkers to doxorubicin and doxorubicin exposure.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1086-1091
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• 2008

The antioxidant activities of the extracts of dangyuja (Citrus grandis Osbeck) leaves were evaluated. The highest phenolic content was obtained from the ethyl acetate fraction (EF) (202.1$\pm$0.8 mg GAE/g dried extract) and it exhibited the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity. The cytoprotective effects of EF on oxidative damage induced by tert-butyl hydroperoxide (t-BHP) in a human hepatoma cell line, HepG2 cells, were investigated to understand the intracellular antioxidant mechanisms. Treatment of HepG2 cells with EF prior to oxidative stress was found to inhibit reactive oxygen species (ROS) generation, lipid peroxidation, and DNA damage in a dose-dependent manner. Gas chromatography-mass spectrometry (GC-MS) studies on EF resulted in tentative identification of 19 compounds representing 94.3% of the total content. Taken together, these results demonstrated that EF has excellent antioxidant activities and thus dangyuja leaves have great potential as a source for natural antioxidant which can be applied in food products.

• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1955-1962
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• 2017

Induction motors are a workhorse for the industry. The condition monitoring and fault analysis are the main concern for the engineers. The bearing is one of the vital segment of the induction machine and the condition of the whole machine is decided based on the condition of the bearing. In the present paper, the vibration signal of the bearing has been used for the analysis. The first line of action is to perform a statistical analysis of the vibration signal which gives trends in signal. To get the location of a fault in the bearing the second action is to develop an index based on Wavelet Packet Transform node energy named as Bearing Damage Index (BDI). Further, Teager-Kaiser Energy Operator (TKEO) has been calculated from higher index value to get the envelope and finally Power Spectral Density (PSD) has been applied to identify the fault frequencies. A performance index has also been developed to compare the usefulness of the proposed method with other existing methods. The result shows that the strong amplitude of fault characteristics and its side bands help to decide the type of fault present in the recorded signal obtained from the bearing.

• Computers and Concrete
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• v.5 no.4
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• pp.343-358
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• 2008

This article focuses on concrete structures submitted to impact loading and is aimed at predicting local damage in the vicinity of an impact zone as well as the global response of the structure. The Discrete Element Method (DEM) seems particularly well suited in this context for modeling fractures. An identification process of DEM material parameters from macroscopic data (Young's modulus, compressive and tensile strength, fracture energy, etc.) will first be presented for the purpose of enhancing reproducibility and reliability of the simulation results with DE samples of various sizes. The modeling of a large structure by means of DEM may lead to prohibitive computation times. A refined discretization becomes required in the vicinity of the impact, while the structure may be modeled using a coarse FE mesh further from the impact area, where the material behaves elastically. A coupled discrete-finite element approach is thus proposed: the impact zone is modeled by means of DE and elastic FE are used on the rest of the structure. The proposed approach is then applied to a rock impact on a concrete slab in order to validate the coupled method and compare computation times.

• International journal of advanced smart convergence
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• v.9 no.3
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• pp.227-231
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• 2020

Recently, the importance of user experience (UX) has been rapidly increasing. Its utilization is emphasized for development of systems, products, and services. User experience is widely used across industries including services, products, processes, society, and culture. Therefore, if it is unsatisfactory, it is likely to have a direct negative impact on the corresponding system, product, or service. The failure to analyze user experience causes significant damage to the project, which may lead to its failure or redevelopment; it is hence necessary to prioritize the verification of UX in the earliest stages of development. The requirements development stage, which is a preceding stage, is an appropriate stage for the verification of user experience because the identification of user needs is completed and prototypes can be implemented. In this paper, we proposed a systematic requirements development stage; it adds user experience verification activities to the requirements development stage, using the Honeycomb model, which is a widely used tool for verifying the overall UX. User experience verification was added to the existing requirements development activities, which consisted of three steps: model definition and requirements placement, discussions between external and internal stakeholders, and review by internal stakeholders. By easily validating the user experience through this systematic requirements development stage, we expect to minimize the damage to the project due to the failure of the user experience analysis and increase the possibility of success.

• Journal of Korean Association for Spatial Structures
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• v.4 no.2 s.12
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• pp.73-80
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• 2004

In this paper, a study of damage detection for 2-Dimensional Truss Structures using the parametric projection filter theorr is presented. Many researchers are interested in inverse problem and one of solution procedures for inverse problems that are very effective is the approach using the filtering algorithm in conjunction with numerical solution methods. In filtering algorithm, the Kalman filtering algorithm is well known and have been applied to many kind of inverse problems. In this paper, the Parametric projection filtering in conjunction with structural analysis is applied to the identification of damages in 2-D truss structures. The natural frequency and modes of damaged truss model are adopted as the measurement data. The effectiveness of proposed method is verified through the numerical examples.

• Journal of the Korean Society of Costume
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• v.53 no.5
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• pp.23-31
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• 2003

The Purpose of this study was to isolate and identify fungi found in excavated clothes dating on the 16th century. As a result of microscoping with LPCB staining, seven isolated strains were classified-Acremonium strictum, Acremonium kiliense, Fonsecaea sp., Candida sp., Trichoderma sp., Cladosporium spp., Penicillium spp.. In the process of isolation and identification of fungi by the sort of textile, more fungi were found in cotton, cotton batt and silk than in ramie and hemp, suggesting that hemp has antibacterial characteristics due to the presence of lignin. In the Comparison washed samples with unwashed ones, there were more kinds of fungi in washed samples. In the cellulase activity test, Acremonium kiliense had the highest level cellulase activity, suggesting that Acremonium killiense has an important Influence on damage of textiles.

• Smart Structures and Systems
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• v.4 no.4
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• pp.391-406
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• 2008

This study attempts to develop a real-time debonding monitoring system for carbon fiber-reinforced polymer (CFRP) strengthened structures by continuously inspecting the bonding condition between the CFRP layer and the host structure. The uniqueness of this study is in developing a new concept and theoretical framework of nondestructive testing (NDT), in which debonding is detected without relying on previously-obtained baseline data. The proposed reference-free damage diagnosis is achieved based on the concept of time reversal acoustics (TRA). In TRA, an input signal at an excitation point can be reconstructed if the response signal measured at another point is reemitted to the original excitation point after being reversed in the time domain. Examining the deviation of the reconstructed signal from the known initial input signal allows instantaneous identification of damage without requiring a baseline signal representing the undamaged state for comparison. The concept of TRA has been extended to guided wave propagations within the CFRP-strengthened reinforced concrete (RC) beams to improve the detectibility of local debonding. Monotonic and fatigue load tests of large-scale CFRP-strengthened RC beams are conducted to demonstrate the potential of the proposed reference-free debonding monitoring system. Comparisons with an electro-mechanical impedance method and an inferred imaging technique are provided as well.