• Title/Summary/Keyword: multi-layered approach

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Linking trade to labor and environmental issues in the multilateral trading system with a focus on the fisheries sector (다자통상제상 노동·환경 이슈의 무역 규범화에 관한 연구: 수산분야를 중심으로)

  • Seo-yeon Oh;Ji-Eun An
    • Asia-Pacific Journal of Business
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    • v.14 no.1
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    • pp.381-396
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    • 2023
  • Purpose - The purpose of this study was to analyze environmental and labor issues and related norms, which are new trade issues that are expanding in bilateral and multilateral trade agreements, and examine the possible impact of these norms on domestic fisheries policies. Design/methodology/approach - In this study, literature research was used as the main research methods. The comparative analysis of international norms and multilateral trade agreements texts related to the environment, labor and trade were conducted. Findings - The new trade norms in the fisheries sector can be represented by labor and environment issues. Since domestic environmental and labor standards do not fully meet the standards of the multilateral trade agreements, it is necessary to ensure that domestic norms are supplemented and relevant policies are newly established through a review of international law on environment and labor. Research implications or Originality - This study confirmed that international norms related to labor and environment in the fisheries sector are mixed with soft norms and binding norms, and each norm is linked in a multi-layered and mutual way. Such international norms are being strengthened in connection with trade agreements and issues.

Characteristic Validation of High-damping Printed Circuit Board Using Viscoelastic Adhesive Tape (점탄성 테이프를 적용한 고댐핑 적층형 전자기판의 기본 특성 검증)

  • Shin, Seok-Jin;Jeon, Su-Hyeon;Kang, Soo-Jin;Park, Sung-Woo;Oh, Hyun-Ung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.5
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    • pp.383-390
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    • 2020
  • Wedge locks have been widely used for spaceborne electronics for mounting or removal of a printed circuit board (PCB) during integration, test and maintenance process. However, it can basically provide a mechanical constraint on the edge of the board. Thus, securing a fatigue life of solder joint for electronic package by limiting board deflection becomes difficult as the board size increases. Previously, additional stiffeners have been applied to reduce the board deflection, but the mass and volume increases of electronics are unavoidable. To overcome the aforementioned limitation, we proposed an application of multi-layered PCB sheet with viscoelastic adhesive tapes to implement high-damping capability on the board. Thus, it is more advantageous in securing the fatigue life of package under launch environment compared with the previous approach. The basic characteristics of the PCB with the multi-layered sheet was investigated through free-vibration tests at various temperatures. The effectiveness of the proposed design was validated through launch vibration test at qualification level and fatigue life prediction of electronic package based on the test results.

Environmental Friendliness Assessment of Golf Courses in the Capital Region of Korea (수도권 지역 골프장의 환경친화성 평가)

  • 김광두;방광자;강현경
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.5
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    • pp.20-30
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    • 2003
  • This study is aimed at establishing the categories and items for ecological assessment and evaluation of the environmental friendliness of golf courses in the capital region of Korea. The categories and items for the assessment have been derived based on the existing literature and interviews with golf experts. This study covers 32 golf courses in the capital region of Korea that are available in terms of data and on-site surveys. In order to conduct a comprehensive assessment of the environmental friendliness of the golf courses, the assessment area was divided into 4 categories that include a total of 14 sub-categories. The 4 categories encompass 1) location, 2) topography, 3) vegetation, and 4) construction. As its sub-categories, the location category includes current land use and zoning in the National Land Use Management Law. Topography has 2 sub-categories in the damage ratio of existing topography, gradient, cut area, and slope height. The assessment of vegetation is largely based on site surveys in the categories of preservation of the existing vegetation, the use of natural resources and existing trees, the component ratio of native tree species, the multi-layered structure of vegetation, and the utilization of water purification plants. In the aspect of construction, afforestation on tile slopes and the utilization of existing surface soil were evaluated. The examination of comparative analysis among the 10 items as a ratio measure showed that the scores were low in the sub-categories of current land we, the use of existing trees, and the multi-layered structure of vegetation. However, the rating results were satisfactory in the 2 sub-categories including cut area, and the utilization of native tree species. Those proved to be contributing factors in the ecological health of the golf courses. According to correlation analysis of the 10 items to the overall ecological rating of each golf course, the sizes of the 32 golf courses were mainly affected by the damage ratio of existing topography, gradient, preservation of vegetation and slope height. This study has the initiative to conduct an ecological assessment of golf courses in the country based on site surveys. The study results revealed that location factors such as current land use, damage ratio of topography and gradient and topographical factors were the main factors affecting the environmental friendliness of golf courses. This indicates indicating the significance of these factors in the future construction practices of golf courses. Furthermore, this study raises the need for follow-up studies to establish more detailed assessment criteria and to develop assessment techniques for areas such as slope afforestation and water purification plants that need a qualitative approach.

An implementation of the mixed type character recognition system using combNET (CombNET 신경망을 이용한 혼용 문서 인식 시스템의 구현)

  • 최재혁;손영우;남궁재찬
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.12
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    • pp.3265-3276
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    • 1996
  • The studies of document recongnition have been focused mainly on Korean documents. But most of documents composed of Korean and other characters. So, in this paper, we propose the document recognition system that can recognize the multi-size, multi font and mixed type characters. We have utilized a large scale network model, "CombNET" which consists of a 4 layered network with combstructure. And we propose recognition method that can recognize characters without discrimination of character type. The first layer constitutes a Kohonen's SOFM network which quantizes an input feature vector space into several sub-spaces and the following 2-4 layers constitutes BP network modules which classify input data in each sub-space into specified catagories. An experimental result demonstrated the usefulness of this approach with the recognition rates of 95.6% for the training data. For the mixed type character documents we obtained the recognition rates of 92.6% and recognition speed of 10.3 characters per second.

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Effective Analysis on the Mechanical Behavior of a Refrigerator using Equivalent Material Properties of Multi-layers (다중재질 접합구조의 등가물성을 이용한 효과적 냉장고 구조 변형 분석에 관한 연구)

  • Park, Jeong-Hyun;Lee, Dong-Kyu;Park, Sang-Hu;Park, Ki-Hong;Ha, Byeong-Kuk;Kim, Hyeong-Sik
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.11
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    • pp.1228-1235
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    • 2012
  • A refrigerator has many components which are made from diverse materials such as metal, polymer, plastic, and rubber. So, it generally requires much time and efforts to build up an analysis model in finite element analysis. In this work, to reduce the computational time and efforts a simplified modeling method was proposed for the analysis of a refrigerator. Occasionally, a stick-slip noise occurs in a refrigerator due to relative slip between shelf and inner-case. When we solve the problem by a FE analysis, we should model the structures with detail for considering the contact conditions; by this reason, too many efforts are consumed in the conventional analysis method. Through this work, we shows the concept of simplifying approach and a good agreement with the results of a real model analysis. And also, the evaluation of the proposed method and the application of contact analysis using the simplified model are discussed.

Simplified Design Methodology for Frequency Filtering Hybrid Composites (주파수 필터링 하이브리드 복합재의 단순화된 설계 방법)

  • Kim, Yoon Jae;Baek, Sang Min;Oh, Won Seok;Go, Jeong In
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.47 no.12
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    • pp.897-903
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    • 2019
  • This paper represents an simplified design method of hybrid composites. The proposed method is very simple compared to conventional design approaches and easy to apply to practical design problems. The method is based on not complex optimization approaches but conventional theories. The equivalent dielectric properties concept and multi-layered dielectric slab theory are an important theoretical background of the proposed method. This approach divide the design domain into several domain which have theoretically different electro- agnetic functionality. Then, the domains are expressed by equivalent dielectric properties. Numerical analysis are performed several types of design candidates. S-parameter test for final design was conducted for validate the proposed approach indirectly.

Vibration analysis of damaged core laminated curved panels with functionally graded sheets and finite length

  • Zhao, Li-Cai;Chen, Shi-Shuenn;Xu, Yi-Peng;Tahouneh, Vahid
    • Steel and Composite Structures
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    • v.38 no.5
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    • pp.477-496
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    • 2021
  • The main objective of this paper is to study vibration of sandwich open cylindrical panel with damaged core and FG face sheets based on three-dimensional theory of elasticity. The structures are made of a damaged isotropic core and two external face sheets. These skins are strengthened at the nanoscale level by randomly oriented Carbon nanotubes (CNTs) and are reinforced at the microscale stage by oriented straight fibers. These reinforcing phases are included in a polymer matrix and a three-phase approach based on the Eshelby-Mori-Tanaka scheme and on the Halpin-Tsai approach, which is developed to compute the overall mechanical properties of the composite material. Three complicated equations of motion for the panel under consideration are semi-analytically solved by using 2-D differential quadrature method. Several parametric analyses are carried out to investigate the mechanical behavior of these multi-layered structures depending on the damage features, through-the-thickness distribution and boundary conditions. It is seen that for the large amount of power-law index "P", increasing this parameter does not have significant effect on the non-dimensional natural frequency parameters of the FG sandwich curved panel. Results indicate that by increasing the value of isotropic damage parameter "D" up to the unity (fully damaged core) the frequency would tend to become zero. One can dictate the fiber variation profile through the radial direction of the sandwich panel via the amount of "P", "b" and "c" parameters. It should be noticed that with increase of volume fraction of fibers, the frequency parameter of the panels does not increase necessarily, so by considering suitable amounts of power-law index "P" and the parameters "b" and "c", one can get dynamic characteristics similar or better than the isotropic limit case for laminated FG curved panels.

Technology Transfer Process of Daegu Automotive Parts Industry (대구 자동차부품산업의 기술이전 프로세스)

  • Kim, Hyo-Mi
    • Journal of the Economic Geographical Society of Korea
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    • v.25 no.1
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    • pp.61-86
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    • 2022
  • This paper analyzes the technology transfer mechanism of companies clustered in a specific economic space from the perspective of absorptive capacity, taking the Daegu automotive parts industry as an example. According to the analysis results, The absorptive capacity of a company was found to be positively related to the supplier, channel, method, and institutional interaction of technology transfer. Low absorptive capacity limits technology transfer by reducing companies' technology search capabilities, while high absorptive capacity gives companies access to technology search and various technology transfer opportunities through formal and informal channels. These results suggest that, in the short term, it is necessary to supplement the search capabilities of companies through preemptive visiting services of local intermediaries for the vitalization of regional technology transfer, while in the long term, a policy approach focusing on enhancing the absorptive capacity of local companies is required. For effective implementation of these policies, a multi-layered governance approach corresponding to each level of companies' absorptive capacities is required in establishing an interface structure that promotes linkage between institutional actors.

Vibrational characteristics of sandwich annular plates with damaged core and FG face sheets

  • Xi, Fei
    • Steel and Composite Structures
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    • v.44 no.1
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    • pp.65-79
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    • 2022
  • The main goal of this paper is to study the vibration of damaged core laminated annular plates with FG face sheets based on a three-dimensional theory of elasticity. The structures are made of a damaged isotropic core and two external face sheets. These skins are strengthened at the nanoscale level by randomly oriented Carbon nanotubes (CNTs) and are reinforced at the microscale stage by oriented straight fibers. These reinforcing phases are included in a polymer matrix and a three-phase approach based on the Eshelby-Mori-Tanaka scheme and on the Halpin-Tsai approach, which is developed to compute the overall mechanical properties of the composite material. In this study the effect of microcracks on the vibrational characteristic of the sandwich plate is considered. In particular, the structures are made by an isotropic core that undergoes a progressive uniform damage, which is modeled as a decay of the mechanical properties expressed in terms of engineering constants. These defects are uniformly distributed and affect the central layer of the plates independently from the direction, this phenomenon is known as "isotropic damage" and it is fully described by a scalar parameter. Three complicated equations of motion for the sectorial plates under consideration are semi-analytically solved by using 2-D differential quadrature method. Using the 2-D differential quadrature method in the r- and z-directions, allows one to deal with sandwich annular plate with arbitrary thickness distribution of material properties and also to implement the effects of different boundary conditions of the structure efficiently and in an exact manner. The fast rate of convergence and accuracy of the method are investigated through the different solved examples. The sandwich annular plate is assumed to have any arbitrary boundary conditions at the circular edges including simply supported, clamped and, free. Several parametric analyses are carried out to investigate the mechanical behavior of these multi-layered structures depending on the damage features, through-the-thickness distribution, and boundary conditions.

Predicting Long-Term Deformation of Road Foundations under Repeated Traffic Loadings (반복 교통하중에 의한 도로지반의 장기변형 예측)

  • Park, Seong-Wan;An, Dong Seok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.5D
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    • pp.505-512
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    • 2010
  • Generally, the repeated traffic loading condition should be considered to predict the long-term deformation on road foundations or foundation systems. However, it is not easy to estimate long-term deformation on multi-layered system like roads and railways. For more quantitative analysis, mechanistic-empirical approach requires proper analytical tool, material's model, and material properties of foundation geomaterials under both traffic and environmental loadings. In this study, therefore, laboratory data from the long-term repeated load triaxial tests were used to predict accumulated deformation on pavement foundations and the results were analyzed based on the nonlinear models and stress state considered. All these results are presented and verified on laboratory based scale using the finite element analysis with the deformation characteristics of foundation geomaterials at various stress states.