• Smart Structures and Systems
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• v.3 no.4
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• pp.455-474
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• 2007

A flexibility-based distributed computing strategy (DCS) for structural health monitoring (SHM) has recently been proposed which is suitable for implementation on a network of densely distributed smart sensors. This approach uses a hierarchical strategy in which adjacent smart sensors are grouped together to form sensor communities. A flexibility-based damage detection method is employed to evaluate the condition of the local elements within the communities by utilizing only locally measured information. The damage detection results in these communities are then communicated with the surrounding communities and sent back to a central station. Structural health monitoring can be done without relying on central data acquisition and processing. The main purpose of this paper is to experimentally verify this flexibility-based DCS approach using wired sensors; such verification is essential prior to implementation on a smart sensor platform. The damage locating vector method that forms foundation of the DCS approach is briefly reviewed, followed by an overview of the DCS approach. This flexibility-based approach is then experimentally verified employing a 5.6 m long three-dimensional truss structure. To simulate damage in the structure, the original truss members are replaced by ones with a reduced cross section. Both single and multiple damage scenarios are studied. Experimental results show that the DCS approach can successfully detect the damage at local elements using only locally measured information.

• Applied Microscopy
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• v.42 no.1
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• pp.43-48
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• 2012

This study shows that ceresin wax, candellila wax and microcrystalline wax mixed together with liquid paraffin oil to produce lipsticks (LS-1, LS-2) and capric/caprylic triglyceride oil added to produce lipsticks (LS-3, LS-4). After each type of lipsticks were molded, LS-1 and LS-3 was put into a cooling chamber ($5^{\circ}C$). LS-2 and LS-4 was put into a cooling chamber ($5^{\circ}C$) for 18 hours and kept in an incubator ($45^{\circ}C$) for 5 hours and put again into a cool chamber ($5^{\circ}C$). After that, the wax's three dimensional network structure was observed under scanning electron microscopy. Regardless of the kind of oil, the LS-1 and LS-3 wax structure had more distinct shape than the lipstick wax structure of LS-2 and LS-4. Also, regardless of the kind of wax, the three dimensional network structure was modified as the storage temperature increased. As a result, the lipstick's molding temperature increased, the wax's structure size also increased and the shape irregularly modified. This modification causes sweating phenomenon which affected lipstick's surface rheological property.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2003.10a
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• pp.26-51
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• 2003

Large scale protein interaction maps provide a new, global perspective with which to analyse protein function. PSIMAP, the Protein Structural Interactome Map, is a database of all the structurally observed interactions between superfamilies of protein domains with known three-dimensional structure in thePDB. PSIMAP incorporates both functional and evolutionary information into a single network. It makes it possible to age protein domains in terms of taxonomic diversity, interaction and function. One consequence of it is to predict the most important protein domain structure in evolution. We present a global analysis of PSIMAP using several distinct network measures relating to centrality, interactivity, fault-tolerance, and taxonomic diversity. We found the following results: ${\bullet}$ Centrality: we show that the center and barycenter of PSIMAP do not coincide, and that the superfamilies forming the barycenter relate to very general functions, while those constituting the center relate to enzymatic activity. ${\bullet}$ Interactivity: we identify the P-loop and immunoglobulin superfamilies as the most highly interactive. We successfully use connectivity and cluster index, which characterise the connectivity of a superfamily's neighbourhood, to discover superfamilies of complex I and II. This is particularly significant as the structure of complex I is not yet solved. ${\bullet}$ Taxonomic diversity: we found that highly interactive superfamilies are in general taxonomically very diverse and are thus amongst the oldest. This led to the prediction of the oldest and most important protein domain in evolution of lift. ${\bullet}$ Fault-tolerance: we found that the network is very robust as for the majority of superfamilies removal from the network will not break up the network. Overall, we can single out the P-loop containing nucleotide triphosphate hydrolases superfamily as it is the most highly connected and has the highest taxonomic diversity. In addition, this superfamily has the highest interaction rank, is the barycenter of the network (it has the shortest average path to every other superfamily in the network), and is an articulation vertex, whose removal will disconnect the network. More generally, we conclude that the graph-theoretic and taxonomic analysis of PSIMAP is an important step towards the understanding of protein function and could be an important tool for tracing the evolution of life at the molecular level.

• Molecules and Cells
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• v.27 no.6
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• pp.651-656
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• 2009

The formation of ${\beta}$-amyloid peptide ($A{\beta}$) is initiated from cleavage of amyloid precursor protein (APP) by a family of protease, ${\alpha}$-, ${\beta}$-, and ${\gamma}$-secretase. Sub W, a substrate peptide, consists of 10 amino acids, which are adjacent to the ${\beta}$-cleavage site of wild-type APP, and Sub M is Swedish mutant with double mutations on the left side of the ${\beta}$-cleavage site of APP. Sub W is a normal product of the metabolism of APP in the secretary pathway. Sub M is known to increase the efficiency of ${\beta}$-secretase activity, resulting in a more specific binding model compared to Sub W. Three-dimensional structures of Sub W and Sub M were studied by CD and NMR spectroscopy in water solution. On the basis of these structures, interaction models of ${\beta}$-secretase and substrate peptides were determined by molecular dynamics simulation. Four hydrogen bonds and one water-mediated interaction were formed in the docking models. In particular, the hydrogen bonding network of Sub M-BACE formed spread over the broad region of the active site of ${\beta}$-secretase (P5-P3'), and the side chain of P2- Asn formed a hydrogen bond specifically with the side chain of Arg235. These are more favorable to the cleavage of Sub M by ${\beta}$-secretase than Sub W. The two substrate peptides showed different tendency to bind to ${\beta}$-secretase and this information may useful for drug development to treat and prevent Alzheimer's disease.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.362-369
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• 2016

Recently, Last to check the security status of various medium and large bridge structures using various kinds of measurement equipment, but most of the methods are used to measure and check the displacement behavior of the bridge by a certain period. In this study, receive GPS satellite signals that can be observed in real time the whole region, a bridge to automatically measure the displacement and behavior characteristics of the structure in real-time in mm over the 24 hours, the measurement information and transmits the data to the wireless network, by making use, it was applied to the real-time monitoring system in connection with a bridge to be able to automatically notify GNSS fine displacement behavior. In fact, analysis and receives the measurement data to GNSS provided in the upper bridge of the middle and large-sized aging for this purpose, measuring USN and at the same time is converted into a three-dimensional position information of a test study was conducted to monitor the bridge displacement in real time. As a result, a vertical displacement of about 0.027~0.037m at the measurement time of day of the measurement point is that the repeated and confirmed.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.790-799
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• 2010

The Upper Devonian Grossmont Formation in Alberta, Canada reserves an estimated 50 billion cubic meters of bitumen and possess about 1/6 of the total bitumen resources in northern Alberta. However, unlike the overlying Athabasca oil sands, non conventional bitumen resources has not been developed as yet. The carbonate rocks of Grosmont Formation have been subject to various stages of diagenesis, including dolomatization and karstification with a strong effect on the distribution of porosity and permeability, which resulted in highly heterogeneous reservoirs. An extensive fracture logging and mapping was performed on total of six boreholes located in the study area to explore the characteristics of fracture geometry system and the subsurface structures of carbonates reservoir that holds bitumen. Fractal dimension was used as a measure of the statistical homogeneity of the fractured rock masses. The applicability of random Cantor dust, Dc, as a fractal parameter was examined systematically. The statistical homogeneity of fractured carbonates rock masses was investigated in the study area. The structural domains of the rock masses were delineated depthwise according to estimated Dc. The major fracture orientation was dominated by horizontal beddings having dip of $0-20^{\circ}$. Also, fractures having high dip angles existed with relatively low frequency. Three dimensional fracture network modeling for each structural domain has been performed based on fracture orientation and intensity, and some representative conceptual models for carbonates reservoir in the study area has been proposed. The developed subsurface conceptual models will be used to capture the geomechanical characteristics of the carbonates reservoir.

• Journal of Korea Foresty Energy
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• v.23 no.1
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• pp.45-68
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• 2004

The word of lignin is derived from the Latin word 'ligum' meaning wood. Lignin is complex polymer consisting of coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol unit and has an amorphous, three dimensional network structure which is hard to be hydrolyzed by acid. Lignin is found in the cell wall of plants lignified. The mode of polymerization of these alcohols in the cell wall lead to a heterogeneous branched and cross-linked polymer in which phenyl propane units are linked by carbon-carbon and carbon-oxygen bonds. This polymerization of precursors, p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol to lignin is formed by enzymic dehydrolyzation. The reaction is initiated by an electron transfer which results in the formation of resonance-stabilized phenoxy radical. The combination of these radicals produces a variety of dimers, trimers and oligomers and so on. Lignin research has been divided into basic and practical application field. The basic studies contains biosynthesis, chemical structure, distribution in the cell wall and reactivity by reductants, oxidants and organic solvents. The application research will be approached the reaction of lignin in various pulp making involving pulp bleaching and its effect on pulp qualities. Lignin also will be studied for the production of fine chemicals, polymer products and the conservation into an energy source like petroleum oil because the amount of lignin produced in pulp making process is more than 51,000,000 tons per year in the world. Both basic and application research must lay emphasis on the development for the utilization of lignin and the pulping process. But these researches can not be completed without understanding lignin structure containing functional groups. Therefore, this paper was focused on the review of lignin formulation which has been studied since 1948 in chronological order. This review was based on monomers, dimers, trimers and tetramers of phenyl propane unit structures which were isolated and identified by different methods from various wood.ious wood.

• Applied Microscopy
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• v.48 no.3
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• pp.55-61
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• 2018

The synaptic vesicle is a specialized structure in presynaptic terminals that stores various neurotransmitters. The actin filament has been proposed for playing an important role in mobilizing synaptic vesicles. To understand the role of actin filament on synaptic vesicle pooling, we characterized synaptic vesicles and actin filament after treatment of brain-derived neurotrophic factor (BDNF) or Latrunculin A on primary cultured neuron from rat embryo hippocampus. Western blots revealed that BDNF treatment increased the expression of synapsin I protein, but Latrunculin A treatment decreased the synapsin I protein expression. The increased expression of synapsin I after BDNF disappeared by the treatment of Latrunculin A. Three-dimensional (3D) tomography of synapse showed that more synaptic vesicles localized near the active zone and total number of synaptic vesicles increased after treatment of BDNF. But the number of synaptic vesicle was 2.5-fold reduced in presynaptic terminals and the loss of filamentous network was observed after Latrunculin A application. The treatment of Latruculin A after preincubation of BDNF group showed that synaptic vesicle number was similar to that of control group, but filamentous structures were not restored. These data suggest that the actin filament plays a significant role in synaptic vesicles pooling in presynaptic terminals.

• The Journal of Natural Sciences
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• v.6 no.1
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• pp.103-108
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• 1993

Zeolites were discovered as a natural mineral more than two hundred ago. In the beginning, the mineral was used as ion-exchange material and adsorbent. After the end of World War II , however, a variety of zeolites have become available in large amounts because of the establishment of low temperature synthesis and the discobery of natural zeolite deposits of sedimentary origin. Various uses of xeolite were developed utilizing the unique crystal strucrure and function of these minerals. In connection with this development remakable progress has also been made in basic stuides on the related geology and mineralogy, crystallization from sols and gels, structure, ion exchange, adsorption and cataiysis. As a result, zeolites, which had been known only as mineral specimens displayed in museums. established a firm position among the high-technology masterials with excellent functional capabilities.

• Journal of Radiation Industry
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• v.5 no.2
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• pp.131-135
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• 2011

In this study, we fabricated the HDPE and ${\alpha}-Al_2O_3$ composites with PE-g-MA as a function of the ${\alpha}-Al_2O_3$ nanopowder weight ratios. The electron beam irradiations on HDPE/${\alpha}-Al_2O_3$ composites were carried out over a range of absorbed doses from 20 to 200 kGy to make three-dimensional network structures. The mechanical properties were characterized using UTM for confirming the changes of the flexural strength and tensile strength. It was observed that the mechanical properties of HDPE were enhanced by the addition of ${\alpha}-Al_2O_3$. However, the strength of the 5 wt% ${\alpha}-Al_2O_3$ added composites decreased due to the nano-powder aggregation. The mechanical properties of composites were increased as increasing the electron beam irradiation up to 150 kGy. We believed that the electron beam irradiated HDPE/${\alpha}-Al_2O_3$ composites can be a good candidate for a variety of industrial applications.