• Steel and Composite Structures
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• v.2 no.1
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• pp.21-34
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• 2002

A model of the process of local buckling in tubular steel structural elements is presented. It is assumed that this degrading phenomenon can be lumped at plastic hinges. The model is therefore based on the concept of plastic hinge combined with the methods of continuum damage mechanics. The state of this new kind of inelastic hinge is characterized by two internal variables: the plastic rotation and the damage. The model is valid if only one local buckling appears in the plastic hinge region; for instance, in the case of framed structures subjected to monotonic loadings. Based on this damage model, a new finite element that can describe the development of local buckling is proposed. The element is the assemblage of an elastic beamcolumn and two inelastic hinges at its ends. The stiffness matrix, that depends on the level of damage, the yielding function and the damage evolution law of the two hinges define the new finite element. In order to verify model and finite element, several small-scale frames were tested in laboratory under monotonic loading. A lateral load at the top of the frame was applied in a stroke-controlled mode until local buckling appears and develops in several locations of the frame and its ultimate capacity was reached. These tests were simulated with the new finite element and comparison between model and test is presented and discussed.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.689-698
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• 2013

The production and characterization of an active recombinant N-acetylgalactosamine-6-sulfate sulfatase (GALNS) in Escherichia coli BL21(DE3) has been previously reported. In this study, the effect of the signal peptide (SP), inducer concentration, process scale, and operational mode (batch and semi-continuous) on GALNS production were evaluated. When native SP was presented, higher enzyme activity levels were observed in both soluble and inclusion bodies fractions, and its removal had a significant impact on enzyme activation. At shake scale, the optimal IPTG concentrations were 0.5 and 1.5 mM for the strains with and without SP, respectively, whereas at bench scale, the highest enzyme activities were observed with 1.5 mM IPTG for both strains. Noteworthy, enzyme activity in the culture media was only detected when SP was presented and the culture was carried out under semi-continuous mode. We showed for the first time that the mechanism that in prokaryotes recognizes the SP to mediate sulfatase activation can also recognize a eukaryotic SP, favoring the activation of the enzyme, and could also favor the secretion of the recombinant protein. These results offer significant information for scaling-up the production of human sulfatases in E. coli.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.350-351
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• 2006

A solid stage sinterizacion model of the WC-Co is applied on this work. These results are compaired with the experimental data obtained for nanometric and micrometric sinter powder in an electric furnace and micrometric in a plasma reactor (using Abnormal Glow Discharge AGD). The correlations obtained allow the prediction of the sintering behavior in AGD for nanometric powder. The activation of the solid state sintering is shown with the decraease of the WC size and the use of AGD

• Kyungpook Mathematical Journal
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• v.21 no.2
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• pp.243-250
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• 1981

• Imaging Science in Dentistry
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• v.45 no.2
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• pp.95-101
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• 2015

Purpose: This study used cone-beam computed tomography (CBCT) to characterize mandibular molar root and canal morphology and its variability in Belgian and Chilean population samples. Materials and Methods: We analyzed the CBCT images of 515 mandibular molars (257 from Belgium and 258 from Chile). Molars meeting the inclusion criteria were analyzed to determine (1) the number of roots; (2) the root canal configuration; (3) the presence of a curved canal in the cross-sectional image of the distal root in the mandibular first molar and (4) the presence of a C-shaped canal in the second mandibular molar. A descriptive analysis was performed. The association between national origin and the presence of a curved or C-shaped canal was evaluated using the chi-squared test. Results: The most common configurations in the mesial root of both molars were type V and type III. In the distal root, type I canal configuration was the most common. Curvature in the cross-sectional image was found in 25% of the distal canals of the mandibular first molars in the Belgian population, compared to 11% in the Chilean population. The prevalence of C-shaped canals was 10% or less in both populations. Conclusion: In cases of unclear or complex root and canal morphology in the mandibular molars, CBCT imaging might assist endodontic specialists in making an accurate diagnosis and in treatment planning.

• Journal of Fashion Business
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• v.3 no.2
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• pp.49-58
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• 1999

The purpose of this study is to investigate a variety of the Indian costume of the Central-South America and to examine the relation and symbolization of each Indian culture arrd costume. A study's method is to be examined through literatues related to the culture and history of Central-South America Indian, photos and references related to costume. The results are as follows. First, an analysis of Indian male of Central-South America reveals that costume types are different according to cultural areas. Second, an analysis Indian female of Central-South America reveals tlrat costume types are differerrt according to cultural areas. Third, a study on colors and patterns of Indian costume and personal ornament in Meso-America culture area reveals that they were influenced on the Maya and Aztec Civilizations. Fourth, a study on colors and patterns of Indian costume and personal ornament in Andes cultural area reveals that they were influenced on the Inca Civilization. Fifth, a type of ponchos is commonly revealed in Meso America and Andes cultural areas because of particular climate. Sixth, a study on Tropical costume types reveals that they are very different from those of Meso-America and Andes culture areas due to its climate and terrain conditions.

• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.217-233
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• 2012

Major elements abundances of Cretaceous to Tertiary volcanic rocks in Kyongsang basin are similar with Southern Volcanic Zone (SVZ) in Andes. Sr, K, Rb, $Ba{\pm}Th$ abundances, which have low ionic charge, are selectively fertile, on the other hand Ta, Nb, Ce, P, Zr, Hf, Sm, Ti, Y, Yb, Sc, Cr abundances are low. K, Sr, Th show characteristic spikes and Nb show remarkable trough on trace elements spider diagram. Trace elements abundances are higher than that of Andes which is supposed to mantle sources of Kyongsang basin volcanic rocks are produced lower degree of partial melting than SVZ in Andes.

• The korean journal of orthodontics
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• v.52 no.2
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• pp.102-111
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• 2022

Objective: To develop and explore the usefulness of an artificial intelligence system for the prediction of the need for dental extractions during orthodontic treatments based on gender, model variables, and cephalometric records. Methods: The gender, model variables, and radiographic records of 214 patients were obtained from an anonymized data bank containing 314 cases treated by two experienced orthodontists. The data were processed using an automated machine learning software (Auto-WEKA) and used to predict the need for extractions. Results: By generating and comparing several prediction models, an accuracy of 93.9% was achieved for determining whether extraction is required or not based on the model and radiographic data. When only model variables were used, an accuracy of 87.4% was attained, whereas a 72.7% accuracy was achieved if only cephalometric information was used. Conclusions: The use of an automated machine learning system allows the generation of orthodontic extraction prediction models. The accuracy of the optimal extraction prediction models increases with the combination of model and cephalometric data for the analytical process.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.344-351
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• 2013

Private participation on public infrastructures projects is being promoted by governments of several developing countries, among them Colombia. As a result, several advantages such as service delivery efficiency, technology application and faster execution of the projects have been recognized. Hence, the Colombian Government is looking for schemes that allow the private investment in projects like hospitals, schools, prisons and public edification. In this paper, experiences in PPP from other countries were analyzed and adjusted to the Colombian environment. As a result, a model adapted to Colombia is presented, based on a well-developed case from Spain. The awarding process is defined by economic criteria, previous compliance of minimum technical exigencies. Once the infrastructure is operating, contractual periodical payments will be done, based on the performance of the facility.

• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.15-28
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• 2013

This paper was made on the basis of geotourism to explain morphological characteristics of Patagonia and Atacama region in the Andes through 10-day fieldwork. The Patagonian landscape was focused on the Torres del Paine National Park, Chile and the Los Glacier National Park, Argentina; on the other hand, the Atacama morphological landscape was investigated around the San Pedro de Atacama. Many geomorphological features such as uplift, semiarid and glacier landscapes can be found in Patagonia, so it is strongly recommended to have an opportunity to enjoy these landforms by geotourism. Massive intrusive rock bodies of granite can be shown in those two National Parks declared a Biosphere Reserve by UNESCO. And, the Atacama Desert located on the forearc depression in the Andes, Chile has also many geomorphological destinations of arid and volcanic landforms; badland, pediplain, pediment, salt lake and geyser. Especially, huge pediplain is one of the greatest view points in the Atacama Desert. Patagonia and Atacama are the best geographical tourism sites to know diverse tectonic landforms made by the conflict between South American and Pacific plates.