• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.295-302
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• 2001

In the present study, we propose the framework which directly links shell finite element to the surface geometric modeling. For the development of a robust shell element, partial mixed variational functional is provided. The NURBS is used to generate the general free form of parameterized shell surfaces. Employment of NURBS makes shell finite element handle the arbitrary geometry of the smooth shell surfaces. The proposed shell finite element model linked with NURBS surface representation provides efficiency for design and analysis and can be directly extended to surface shape optimization problems in future work.

• Journal of Ship and Ocean Technology
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• 제12권2호
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• pp.1-15
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• 2008

The main idea of this paper introduce stochastic structural parameters and random dynamic excitation directly into the dynamic functional variational formulations, and developed the nonlinear dynamic analysis of a stochastic variational principle and the corresponding stochastic finite element method via the weighted residual method and the small parameter perturbation technique. An interpolation method was adopted, which is based on representing the random field in terms of an interpolation rule involving a set of deterministic shape functions. Direct integration Wilson-${\theta}$ Method was adopted to solve finite element equations. Numerical examples are compared with Monte-Carlo simulation method to show that the approaches proposed herein are accurate and effective for the nonlinear dynamic analysis of structures with random parameters.

• 대한기계학회논문집A
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• 제23권7호
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• pp.1205-1214
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• 1999

A new quadrilateral plane stress element is developed for efficient and accurate analysis of thermal stress problems. It is convenient to use the same mesh and the same shape functions for thermal analysis and stress analysis. But, because of the inconsistency between deformation related strain field and thermal strain field, oscillatory responses and considerable errors in stresses are resulted in. To avoid undesired oscillations, strain approximation is enhanced by supplementing several assumed strain terms based on the variational principle. Thermal deformation is incorporated into the generalized mixed variational principle for displacement, strain and stress fields, and basic equations for the modified enhanced assumed strain method are derived. For the stress approximation of bilinear elements, the $5{\beta}$ version of Pian and Sumihara is adopted. The numerical results for several problems show that the present element behaves well and reduces oscillatory responses. it also results in almost the same magnitude of error as compared with the quadratic element.

• Bulletin of the Korean Chemical Society
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• 제24권6호
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• pp.728-730
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• 2003

Bond lengths, harmonic vibrational frequencies and dissociation energies of TlAt are calculated at ab initio molecular orbital and density functional theory using effective spin-orbit operator and relativistic effective core potentials. Spin-orbit effects estimated from density functional theory are in good agreement with those from ab initio calculations, implying that density functional theory with effective core potentials can be an efficient and reliable methods for spin-orbit interactions. The estimated $R_e$, $ω_e$ and $D_e$ values are 2.937 ${\AA}$, 120 $cm^{-1}$, 1.96 eV for TlAt. Spin-orbit effects generally cause the bond contraction in Group 13 elements and the bond elongation in the Group 17 elements, and spin-orbit effects on Re of TlAt are almost cancelled out. The spinorbit effects on $D_e$ of TlAt are roughly the sum of spin-orbit effects on $D_e$ of the corresponding element hydrides. Electron correlations and spin-orbit effects are almost additive in the TlAt molecule.

• 한국식품조리과학회지
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• 제32권5호
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• pp.656-663
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• 2016

Purpose: This study was aimed to compare the nutritional content of the life stages of Tenebrio molitor. Methods: Nutritional element analysis comprised 12 minerals, 18 amino acids, 4 vitamins, and 12 fatty acids in larval, pupal, and adult stages. Nutritional element content was expressed as a percentage of 100 g of sample and determined in raw and freeze-dried samples to assess the food value of the insect. Results: Moisture, crude protein, and crude fat contents in raw samples were 63.5%, 23.19%, and 3.96%, respectively. Moisture content was significantly higher in the adult stage than in larval and pupal stages, whereas crude fat and crude ash contents were lower. Mineral composition of the mealworm showed K, P, and Mg in decreasing order of content, with no differences among life stages. Total amino acid content increased from adult, pupal to larval stages, in order with each stage's growth, without difference in amino acid composition. Seventy-six to 78% of total fatty acid corresponded to unsaturated fatty acids, with oleic acid as the most abundant. In addition, fatty acid content was high in the adult stage, and clear differences were observed between life stages. Finally, vitamins B1 and B3 showed similar content between life stages, whereas vitamin B2 showed a higher content the adult than larval and pupal stages. A higher folate content was observed in pupal and adult stages than in the larval stage. Although freeze-dried samples showed a higher nutritional content than raw samples, both samples were similar in composition and content between life stages, suggesting the suitability of freeze-dried samples for use as food materials. Conclusion: These results may provide a basis for more diversified industrial applications of the Tenebrio molitor.

• 한국군사과학기술학회지
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• 제12권6호
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• pp.739-749
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• 2009

Ever since gold was found, this element has fascinated human beings. It is stable in air, and is illuminating for several thousands years without changing its colors. Nanoparticles are the basic nanommaterials, and, particularly gold nanoparticles show unique properties which are not shown in bulk states. Scientists are trying to apply these new properties to catalysts, bioscience, optics, etc. Judging from the current research activities, one can envisage that gold nanoparticles can play a major role in opening a new era in diagnoses and treatment of diseases like cancers. However to apply the nanoparticles one must modify the surface of the nanoparticles in order to give the materials certain functionalities. It certainly is worth to review the current research status and challenges in the area of functional gold nanoparticles.

• 시스템엔지니어링학술지
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• 제9권2호
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• pp.69-82
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• 2013

US DoD operated JCIDS(Joint Capability Integration and Development System) for top down requirement generation. Although the JCIDS can be a good practice for the countries which are trying to shift from bottom up to top down requirement generation, it contains many processes related with review and approval. In this study we structured a joint capability integration and development process from the JCIDS eliminating the organization dependent review or approval process so that it can be applied to any organization with some modification. Furthermore we implemented the process in the computer aided systems engineering tool, Cradle, for convenient use of the process. The result of this study can provide a basic process for top down capability development, and an efficient why of doing each element of the process using CASE tool.

• Progress in Superconductivity
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• 제1권1호
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• pp.51-55
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• 1999

A Ni/Ag/Stainless steel 310S(SS310S) multi-layer sheet has been fabricated by a combination of vacuum brazing, cold rolling and texture annealing processes. After heat-treating the thin Ni/Ag/SS310S multi-layer sheet at $900^{\circ}C$ for 2h, development of (100)<001>cube texture on Ni surface was revealed by (111) pole figure. Quantitative chemical analysis was made by EPMA for the cross-section of the Ni/Ag/SS310S multi-layer sheet. EPMA results showed that Ag diffusion into the Ni layer, which may suppress the cube texture development, was negligible. A small amount of Cr atoms were detected in the Ni layer. It showed that Ag can be used as a chemical barrier of alloying element atoms in Ni layer for the Ni/Ag/SS310S multi-layer sheet and a strong cube texture was developed for the Ni layer in the Ni/Ag/SS310S multi-layer sheet.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.18-20
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• 1994

The axisymmetric variational approach employing localized functional is applied to calculate the leakage magnetic field from an induction heating system consisting of an exciting coil and a conducting circular plate. The open boundary is treated by introducing the exterior functional which is representated using the spherical fundamental solutions. For the application to the voltags source problems, the currents on the exciting coil is treated as unknowns. Our results are compared with the previous results, which showed good agreements.

• Genomics & Informatics
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• 제19권1호
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• pp.3.1-3.12
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• 2021

Functional interpretation of noncoding genetic variants associated with complex human diseases and traits remains a challenge. In an effort to enhance our understanding of common germline variants associated with lung cancer, we categorize regulatory elements based on eight major cell types of human lung tissue. Our results show that 21.68% of lung cancer-associated risk variants are linked to noncoding regulatory elements, nearly half of which are cell type-specific. Integrative analysis of high-resolution long-range chromatin interactome maps and single-cell RNA-sequencing data of lung tumors uncovers number of putative target genes of these variants and functionally relevant cell types, which display a potential biological link to cancer susceptibility. The present study greatly expands the scope of functional annotation of lung cancer-associated genetic risk factors and dictates probable cell types involved in lung carcinogenesis.