• Journal of the Korean Wood Science and Technology
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• v.37 no.1
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• pp.114-120
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• 2009

The bark of Populus alba ${\times}$ glandulosa was collected, air-dried and extracted with 70% aqueous acetone. Then it was successively partitioned with n-hexane, $CH_2Cl_2$, EtOAc and $H_2O$. Repeated Sephadex LH-20 column chromatography and preparative TLC on the EtOAc soluble fraction gave a grandidentatin isomer. The structure was elucidated as grandidentatin A (cis-2-hydroxycyclohexyl 6-O-p-coumaroyl-${\beta}$-D-glucopyranoside) on the basis of spectroscopic evidences such as $^1H$-NMR, $^{13}C$-NMR, 2D-NMR and MALDI TOF-MS spectrum followed by acid hydrolysis. Grandidentatin A was identified here for the first time in Populus alba ${\times}$ glandulosa bark, and to the bset of our knowledge it has not been reported in any other literature.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.10
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• pp.1211-1222
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• 2011

It is necessary to use prestressed modal analysis to calculate the modal frequencies and mode shapes of a prestressed structure such as a spinning blade, a preloaded structure, or a thermally deformed pipe, because the prestress effect sometimes causes significant changes in the frequencies and mode shapes. When the finite element model under consideration has a very large number of degrees of freedom, repeated prestressed modal analyses for investigating the prestress effects might become too computationally expensive to finish within a reasonable design-process time. To alleviate these computational difficulties, a Krylov subspace-based model order reduction, which reduces the number of degrees of freedom of the original finite element model and speeds up the necessary prestressed modal analysis with the reduced order models (ROMs), is presented. The numerical process for the moment-matching model reduction is performed directly on the full order models (FOMs) (modeled in ANSYS) by the Arnoldi process. To demonstrate the advantages of this approach for performing prestressed modal analysis, the prestressed wheel and the compressor impeller under their high-speed rotation are considered as examples.

• Journal of KIISE:Software and Applications
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• v.35 no.2
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• pp.128-136
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• 2008

Recognition of parallel structure at early stage of sentence parsing can reduce the complexity of parsing. In this paper, we propose an unsupervised language-independent probabilistic model for recongition of parallel noun structures. The proposed model is based on the idea of swapping constituents, which replies the properties of symmetry (two or more identical constituents are repeated) and of reversibility (the order of constituents is inter-changeable) in parallel structures. The non-symmetric patterns that cannot be captured by the general symmetry rule are resolved additionally by the modifier information. In particular this paper shows how the proposed model is applied to recognize Korean parallel noun phrases connected by "wa/kwa" particle. Our model is compared with other models including supervised models and performs better on recongition of parallel noun phrases.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.2
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• pp.326-340
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• 2017

This study explores the daily life of Korean designers in New York. We use in-depth interviews within the daily lives of participants to first reveal the time structure and meaning of everyday life. In this everyday time frame, this study reveals the content and meaning of life in New York, which is especially useful for fashion majors. Participants were 11 single Korean women around 30 years old working as designers in New York. Data was collected from Manhattan, New York, from November 2013 to February 2014 through the use of in-depth interviews and participant observation. Data collected daily life information on time usage, money, and energy that is first summarized into 229 meaning units. In the following, 55 central meanings were derived from stories common to behaviors for study participants and 19 subcategories were compressed into academic language. Finally, the generalized categories are divided into six categories of study life, work life, future life, family life, leisure life and fashion life. As a result of the first study, the daily time structure consisted of customary public time and personal repeat time. Second, the customary public time categories included the studying for 'Beginning to jump again to the best', 'Now working as a designer in New York', and future life expecting 'Future growing as a career woman'. Repeated personal time categories include family life: 'A single life of a lonely and poor gentile', leisure life: 'Healing life that is supported by abundant advanced culture', and fashion life: 'New York fashion life coexist with harmony'. Third, work was the center of everyday life for study participants versus fashion and leisure that were central to everyday life when not working.

• Korean Journal of Acupuncture
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• v.28 no.1
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• pp.125-137
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• 2011

Objectives : The Primo system is a hypothesis on the new circulation system. It orginates from Bonghan theory. Bonghan theory is about the anatomical substance of acupuncture point and meridian system. It has been regarded as a misunderstanding of the lymphatic system or as a made-up story for the past 40 years. Since 2002, many studies have been published either to support the theory or to refute the old viewpoint. But there are still difficulties about the proper sampling. The purpose of this study is to find out the discriminative criteria of Organ Surface Primo sytem by reviewing the Kim Bonghan's publications. Methods : Abstract of description about the Organ Surface Primo system in 5 publications of Kim Bonghan are weighted by the reverse order of publication. Results and Conclusions : 6 characters of anatomical structure and 11 characters of histological structure are founded as repeated descriptions. We hope that this summarized characteristics would be a good guide to Primo system experiments.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.633-636
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• 2008

Concrete structures are occur many various deteriorations in the course of time and many efforts have progressed to improve on performance of concrete. The purpose of this study is to evaluate the durability of latex modified mortar in order to repair concrete structure which are happened deterioration. In this study, we tested plastic shrinkage, drying shirnkage, repeated freezing and thawing, permeability and resistance of chemical solution. Latex modified mortar and two kinds of sprayed polymer mortar used on durability test. As a result of test, latex modified repair mortar was exhibited durablilty improvement compared to the conventional sprayed polymer mortars. It is judged the fact that latex modified mortar have no problem in site application but additionally many research will be necessary.

• Journal of Korean Association for Spatial Structures
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• v.10 no.4
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• pp.113-122
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• 2010

Space frame structures are included in the large spatial structures and can adopt various structure types. But, it is not easy to choose the optimal member size and shape because it depends on the structural engineer's experience and the repeated trial and error. Therefore, in this study, the final goal is to help the designer with the selection of the optimum shape. First, various space frame structures with ellipse dome and vault complex types are chosen and the shape generation method is considered to generate the nodes, coordinates and members. In optimal design process of space frame structure, each node coordinate changes according to height variation or the number of rings. Therefore, the auto generation technique of nodes and members is required in order to consider this phenomenon in optimal design process. Next, the shape generation module is created, base on the shape generation method. This module is connected with the analysis module and the optimization algorithm. Finally, the example model is presented for the evaluation of the efficiency of optimization algorithms.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.6
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• pp.419-423
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• 2015

The flowing caused by artificial upwelling structure occurs ascending water flowing and vortex of rear side. In this moment, plentiful nutrient in the bottom water moves to the surface of the water and makes those plankton and fishing ecology promoted so that the fishing productivity can be enhanced. In this study, the changes of the upwelling flowing is included in consideration of the conditions of stratification by using CFD. In the conclusion, the closer upwelling effect is from the artificial upwelling structure, the better effectiveness comes out. Regardless of the conditions of stratification, only the upwelling feature from the bottom to the surface was shown up. But considering the conditions of stratification, the repeated flowing feature between upwelling and downwelling was verified.

• KIISE Transactions on Computing Practices
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• v.22 no.8
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• pp.357-362
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• 2016

A social network or bio network is one of the complex networks that are formed by connecting specific relationships between interacting objects. Usually, these networks consist of community structures. Automatically detecting the structures is an important technique to understand and control the interaction objects. However, the topologies and structures of the networks change by interactions of the objects, with respect to time. Conventional techniques for finding the community structure have a high computational complexity. Additionally, the methods inefficiently deal with repeated computation concerning graph operation. In this paper, we propose an incremental technique for detecting interaction-based communities in dynamic networks. The proposed technique is able to efficiently find the communities, since there is an awareness of changed objects from the previous network, and it can incrementally reuse the previous community structure.

• Applied Chemistry for Engineering
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• v.30 no.1
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• pp.43-48
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• 2019

This study investigated the feasibility of $CaSnO_3$ particles as an oxygen carrier in chemical looping combustion (CLC). $CaSnO_3$ particles had a perovskite crystal structure and showed the structural stability after repeated reduction-oxidation reactions. The oxygen transfer capacity was 15.4 wt% almost the same as the calculated theoretical value from the crystal structure transformation during reduction. After $10^{th}$ cycles of reduction and oxidation, the oxygen transfer capacity and rate were still maintained constantly at an operating temperature. In conclusion, $CaSnO_3$ particles could be a good alternative material as an oxygen carrier in CLC.