• Title/Summary/Keyword: rational functions

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A Study on Culture Commodity Design for Desk Service - Focused on Culture Commodity Design with the Hahoe Tel - (wooden mask national treasure No121) (데스크 서비스 문화상품 디자인 개발 연구 - 하회탈을 모티브로한 문화상품 디자인을 중심으로 -)

  • Seo, Seok-Min;Shin, Rang-Ho
    • Journal of the Korea Furniture Society
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    • v.18 no.3
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    • pp.211-223
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    • 2007
  • 21 Century is said the age of cultural industry. In this cultural Industry one of very important factors which guides this times is the exploitation of cultural goods, which is based on regional identity. Therefore, at this point of time when its weighty has been raised, the aim of this study is to fill the image Korean tradition and modernity culture in them, through the search on their characteristics among regions and nations, desk the cultural service goods which gets survival power of traditional and cultural identity. Nine existing Hahoe masks are changed into nine new cultural items, which are presented the nine dreams of Hahoe masks. As consumer's choice is diversified by a set of products, main concept in this study is the focus on modernity, rationality, traditionality and popularity. The main concept of this study is on rational functions and convenience, the harmony of tradition and modernity. As said above, in the process of manufacture the mass production of goods is stressed, and by getting the composition and making a set of goods, the choice of consumers will be extended. Getting ideal globalization by the coexistence of tradition and modernity on goods, is very important. Consequently, cultural goods must be recognized as a factor of its medium, and also, on domestic cultural goods people's interest must be risen all the more.

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Development of Environmental Stress-Tolerant Plants by Gene Manipulation of Antioxidant Enzymes

  • Kwon, Suk-Yoon;Lee, Haeng-Soon;Kwak, Sang-Soo
    • The Plant Pathology Journal
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    • v.17 no.2
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    • pp.88-93
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    • 2001
  • Oxidative stress is one of the major limiting factor in plant productivity. Reactive oxygens species (ROS) generated during metabolic processes damage cellular functions and consequently lead to disease, senescence and cell death. Plants have evolved an efficient defense system by which the ROS is scavenged by antioxidant enzymes such as superoxide dismutase (SOD) and ascorbate peroxidase (APX). Attempts to reduce oxidative damages under the stress conditions have included the manipulation of 갠 scavenging enzymes by gene transfer technology. Increased SOD activities of transgenic plants lead to increased resistance against oxidative stresses derived from methyl viologen (MV), and from photooxidative damage caused by high light and low temperature. Transgenic tobacco plants overexpressing APX showed reduced damage following either MV treatment of photooxidative treatment. Overexpression of glutathion reductase (GR) leads to increase in pool of ascorbate and GSH, known as small antioxidant molecules. These results indicate through overexpression of enzymes involved in ROS-scavenging could maintain or improve the plant productivities under environment stress condition. In this study, the rational approaches to develop stress-tolerant plants by gene manipulation of antioxidant enzymes will be introduced to provide solutions for the global food and environmental problems in the $21^\textrm{st}$ century.

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Output-only modal parameter identification for force-embedded acceleration data in the presence of harmonic and white noise excitations

  • Ku, C.J.;Tamura, Y.;Yoshida, A.;Miyake, K.;Chou, L.S.
    • Wind and Structures
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    • v.16 no.2
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    • pp.157-178
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    • 2013
  • Output-only modal parameter identification is based on the assumption that external forces on a linear structure are white noise. However, harmonic excitations are also often present in real structural vibrations. In particular, it has been realized that the use of forced acceleration responses without knowledge of external forces can pose a problem in the modal parameter identification, because an external force is imparted to its impulse acceleration response function. This paper provides a three-stage identification procedure as a solution to the problem of harmonic and white noise excitations in the acceleration responses of a linear dynamic system. This procedure combines the uses of the mode indicator function, the complex mode indication function, the enhanced frequency response function, an iterative rational fraction polynomial method and mode shape inspection for the correlation-related functions of the force-embedded acceleration responses. The procedure is verified via numerical simulation of a five-floor shear building and a two-dimensional frame and also applied to ambient vibration data of a large-span roof structure. Results show that the modal parameters of these dynamic systems can be satisfactorily identified under the requirement of wide separation between vibration modes and harmonic excitations.

A Reliability Analysis Application and Comparative Study on Probabilistic Structure Design for an Automatic Salt Collector (자동채염기의 확률론적 구조설계 구현을 위한 신뢰성 해석 응용과 비교연구)

  • Song, Chang Yong
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.12
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    • pp.70-79
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    • 2020
  • This paper describes a comparative study of characteristics of probabilistic design using various reliability analysis methods in the structure design of an automatic salt collector. The thickness sizing variables of the main structural member were considered to be random variables, including the uncertainty of corrosion, which would be an inevitable hazard in the work environment of the automatic salt collector. Probabilistic performance functions were selected from the strength performances of the automatic salt collector structure. First-order reliability method, second-order reliability method, mean value reliability method, and adaptive importance sampling method were applied during the reliability analyses. The probabilistic design performances such as reliability probability and numerical costs based on the reliability analysis methods were compared to the Monte Carlo simulation results. The adaptive importance sampling method showed the most rational results for the probabilistic structure design of the automatic salt collector.

Algorithm for Computational Age Dating of Nuclear Material for Nuclear Forensic Purposes

  • Park, Jaechan;Song, Jungho;Ju, Minsu;Chung, Jinyoung;Jeon, Taehoon;Kang, Changwoo;Woo, Seung Min
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.20 no.2
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    • pp.171-183
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    • 2022
  • The parent and daughter nuclides in a radioactive decay chain arrive at secular equilibrium once they have a large half-life difference. The characteristics of this equilibrium state can be used to estimate the production time of nuclear materials. In this study, a mathematical model and algorithm that can be applied to radio-chronometry using the radioactive equilibrium relationship were investigated, reviewed, and implemented. A Bateman equation that can analyze the decay of radioactive materials over time was used for the mathematical model. To obtain a differential-based solution of the Bateman equation, an algebraic numerical solution approach and two different matrix exponential functions (Moral and Levy) were implemented. The obtained result was compared with those of commonly used algorithms, such as the Chebyshev rational approximation method and WISE Uranium. The experimental analysis confirmed the similarity of the results. However, the Moral method led to an increasing calculation uncertainty once there was a branching decay, so this aspect must be improved. The time period corresponding to the production of nuclear materials or nuclear activity can be estimated using the proposed algorithm when uranium or its daughter nuclides are included in the target materials for nuclear forensics.

ON TRANSCENDENTAL MEROMORPHIC SOLUTIONS OF CERTAIN TYPES OF DIFFERENTIAL EQUATIONS

  • Banerjee, Abhijit;Biswas, Tania;Maity, Sayantan
    • Bulletin of the Korean Mathematical Society
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    • v.59 no.5
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    • pp.1145-1166
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    • 2022
  • In this paper, for a transcendental meromorphic function f and α ∈ ℂ, we have exhaustively studied the nature and form of solutions of a new type of non-linear differential equation of the following form which has never been investigated earlier: $$f^n+{\alpha}f^{n-2}f^{\prime}+P_d(z,f)={\sum\limits_{i=1}^{k}}{p_i(z)e^{{\alpha}_i(z)},$$ where Pd(z, f) is a differential polynomial of f, pi's and αi's are non-vanishing rational functions and non-constant polynomials, respectively. When α = 0, we have pointed out a major lacuna in a recent result of Xue [17] and rectifying the result, presented the corrected form of the same equation at a large extent. In addition, our main result is also an improvement of a recent result of Chen-Lian [2] by rectifying a gap in the proof of the theorem of the same paper. The case α ≠ 0 has also been manipulated to determine the form of the solutions. We also illustrate a handful number of examples for showing the accuracy of our results.

The Development of the Drawing Information Management System Based on Group Technology (Group Technology를 이용한 설계정보관리 시스템의 개발)

  • H.S. Moon;Kim, S.H.
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.1
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    • pp.58-68
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    • 1997
  • In order to provide economic high-quality products to customers in a timely manner, companies have tried much effort to decrease the time period of engineering design and information management. As a part of this effort, we have developed the Drawing Information Management System(DIMS) based ofn GT(Group Technology) that could decrease design processing time by speedy and rational management of design processes. The characteristics of DIMS are as follows: First, the concept of Concurrent Engineering was applied to DIMS. Through LAN, reviewers are able to attach comments to dlectronic documents by anno- tation functions called Mark-up. The reviewer annotations are collected and combind with the original document to revise the documents. Second, we have developed a Classification and Coding(C&C) system suitable for electronic component parts bassed on GT(Group Technology). The C&C system makes both parts and drawing with similar characteriscs into families and helps users search existing documents or create new drawings promptly. Finally, DIMS provides the Engineering BOM(Bill of Material) using the concept of Family BOM based on model options.

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Deformation estimation of plane-curved structures using the NURBS-based inverse finite element method

  • Runzhou You;Liang Ren;Tinghua Yi ;Hongnan Li
    • Structural Engineering and Mechanics
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    • v.88 no.1
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    • pp.83-94
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    • 2023
  • An accurate and highly efficient inverse element labelled iPCB is developed based on the inverse finite element method (iFEM) for real-time shape estimation of plane-curved structures (such as arch bridges) utilizing onboard strain data. This inverse problem, named shape sensing, is vital for the design of smart structures and structural health monitoring (SHM) procedures. The iPCB formulation is defined based on a least-squares variational principle that employs curved Timoshenko beam theory as its baseline. The accurate strain-displacement relationship considering tension-bending coupling is used to establish theoretical and measured section strains. The displacement fields of the isoparametric element iPCB are interpolated utilizing nonuniform rational B-spline (NURBS) basis functions, enabling exact geometric modelling even with a very coarse mesh density. The present formulation is completely free from membrane and shear locking. Numerical validation examples for different curved structures subjected to different loading conditions have been performed and have demonstrated the excellent prediction capability of iPCBs. The present formulation has also been shown to be practical and robust since relatively accurate predictions can be obtained even omitting the shear deformation contributions and considering polluted strain measures. The current element offers a promising tool for real-time shape estimation of plane-curved structures.

A study on the Spatial Arrangement and Area of Senior Sharehouses in Japan (일본의 시니어 쉐어하우스 공간배치 및 면적 연구)

  • Ju, Hyun-Jin;Moon, Jeong-Min
    • Journal of the Korean housing association
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    • v.26 no.2
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    • pp.13-20
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    • 2015
  • Single household is expected to be the typical form of future Korean elderly household from reduction of household size and rapid growth of the elderly. As Japanese solve the same problem with Senior Sharehouse, a case study on Senior Sharehouse in japan focused on the Spatial Arrangement and Spatial Composition could suggest an potential applications in Korea. In conclusion, compare to Korea, the Senior Sharehouse in Japan supplies additional $7.5{\sim}9.3m^2$ more space to support the physical movement of the elderly and to help the elderly to solve various functions at one space. The independence and privacy of residents are also assured by supplying single occupancy. Space analysis shows that public space is as spacious (47.3~55%) as personal space. The result of the Space analysis suggests that the sharehouse provides rational ratio of space to assure residents' independence. It was supposed that the center type would be the main stream of the Spatial Arrangement for sharehouse considering its characteristic of sharing space. But, the Senior Sharehouse in Japan prefers corner type. The guarantee of personal space is being considered as a important characteristic. As a result of case analysis, Senior Sharehouse can be a proper type of house for single elderly household and present study can be used for the baseline data to solve the residence problem for single elderly household in Korea.

Next Generation Dairy Processing Science and Technology: Functional and Rational in Dairy Industry

  • Charchoghlyan, Haykuhi
    • Journal of Dairy Science and Biotechnology
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    • v.33 no.3
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    • pp.167-170
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    • 2015
  • The dairy industry, as part of the broader agricultural sector, is classified as a basic industry to the Korea economy. Basic industries provide income to a region by producing an output, purchasing production inputs, services and labor. An integrated, multidisciplinary approach for the next generation of dairy products with added health benefits represent the direct economic contribution. The commercialization of "nutritional" functional foods can only be successful if the consumer is confident in the scientific validity of the claims. Modern biotechnologies such as genomics, genetic expression and biomarkers of health performance suggested to whole dairy products, such as fluid milk, butter, cheese, ice cream and frozen dessert products (German, 1999). The following definition makes the point that dairy products can provide a nutritional value beyond the basic nutritional requirements: 1) The dairy industry has the opportunity to improve the health and well-being of its customers and/or to reduce their risk of disease through dairy products with added activities. 2) Functional dairy products are those that can be demonstrated to benefit target functions in the body in a way that improves the state of health and /or reduces the risk of disease. They are food products that are consumed as part of a normal diet rather than pills or supplements. 3) Dairy products based on functionality will need to link the scientific basis of such functionality to the communication of its benefit to the general public. 4) Both the efficacy and the safety of the food components with health benefits will require evidence based on the measurement of scientific biomarkers relevant to their biological responses and health end points. 5) Sound evidence from human studies based on intermediate health end points using accepted biomarkers will provide the basis for promotional messages divided into two categories-enhanced function and reduced risk of disease. 6) Success in solving key scientific and technological challenges will only be achieved by interdisciplinary research programs to exploit the scientific concepts in functional dairy science.

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