• Title/Summary/Keyword: Joint Energy

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A Study on education program for human resource development on concentrating the enterprise participation (참여기업 중심형 인력양성 교육 프로그램에 관한 연구)

  • Chae, Myeong-Suk
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.64 no.4
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    • pp.337-342
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    • 2015
  • The company of 4 core materials that are needed for photovoltaic generation is located in area around this university in Gunsan, Saemangeum. And also, it was almost completed the value chain about the production of Polysilicon, Ingot, Wafer, modules and the design, construction of generation system. The industry-academy-government has understood that because of the relative companies' production and investment, it leads to a supply and demand of manpower and thus will have field centered manpower education. This program will help the problem of lack of manpower in relative companies by establishing competitive major agreement like vocational education system. Also, the university and the participating company in joint have pushed ahead field business education to make the least of industrial-education's mismatch, the training of professional manpower connected with related industries to make the universities chemical characteristics, companies securing excellent manpower and contributed to the revitalization of the regional economy. In this paper, are aware that photovoltaic industry is a future strategic industry for the country, so we will train the immediately site adapting manpower for the area of photovoltaic material and system as our goal. This is shown results of education operation for 4 years.

Reproducibility and validity of semi-quantitative food frequency questionnaire measuring dietary trans-fatty acids intake among Korean adults

  • Joh, Hee-Kyung;Oh, Seung-Won;Lee, Eun
    • Nutrition Research and Practice
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    • v.9 no.1
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    • pp.99-105
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    • 2015
  • BACKGROUND/OBJECTIVES: Compelling evidence indicates that consumption of trans-fatty acids (TFA) is associated with a wide range of diseases. However, few validated tools for TFA intake assessment are available in Korea. We aimed to validate a food frequency questionnaire (FFQ) estimating usual intake of TFA in Korean adults. MATERIALS/METHODS: Eighty-two healthy adults completed an FFQ with a 3-day diet record (3DDR), and 58 completed a second FFQ at a 1-month interval. To assess the reproducibility of the FFQ, we compared estimated TFA intakes from each FFQ. To assess the validity, we compared estimates from the FFQ with those from the 3DDR. RESULTS: The FFQ was reproducible (Spearman r = 0.71) and provided modest correlations with the 3DDR (Spearman r = 0.38). After adjustment for total energy intake, the correlations increased (r = 0.45). Measurement-error correction also de-attenuated the correlations (r = 0.57). When quintiles of the FFQ and 3DDR were joint-classified, 9% on average were misclassified into extreme quintiles. CONCLUSIONS: Our findings suggest that the developed FFQ is reproducible and reasonably valid in categorizing individuals according to TFA intakes among healthy young and middle aged adults in Korea.

Flexible Voltage Support Control with Imbalance Mitigation Capability for Inverter-Based Distributed Generation Power Plants under Grid Faults

  • Wang, Yuewu;Yang, Ping;Xu, Zhirong
    • Journal of Power Electronics
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    • v.16 no.4
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    • pp.1551-1564
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    • 2016
  • The high penetration level of inverter-based distributed generation (DG) power plants is challenging the low-voltage ride-through requirements, especially under unbalanced voltage sags. Recently, a flexible injection of both positive- (PS) and negative-sequence (NS) reactive currents has been suggested for the next generation of grid codes. This can enhance the ancillary services for voltage support at the point of common coupling (PCC). In light of this, considering distant grid faults that occur in a mainly inductive grid, this paper proposes a complete voltage support control scheme for the interface inverters of medium or high-rated DG power plants. The first contribution is the development of a reactive current reference generator combining PS and NS, with a feature to increase the PS voltage and simultaneously decrease the NS voltage, to mitigate voltage imbalance. The second contribution is the design of a voltage support control loop with two flexible PCC voltage set points, which can ensure continuous operation within the limits required in grid codes. In addition, a current saturation strategy is also considered for deep voltage sags to avoid overcurrent protection. Finally, simulation and experimental results are presented to validate the effectiveness of the proposed control scheme.

Massless Links with External Forces and Bushing Effect for Multibody Dynamic Analysis

  • Sohn, Jeong-Hyun;Yoo, Wan-Suk;Hong, Keum-Shik;Kim, Kwang-Suk
    • Journal of Mechanical Science and Technology
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    • v.16 no.6
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    • pp.810-818
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    • 2002
  • When the contribution of lightweight components to the total energy of a system is small, tole inertia effects are sometimes ignored by replacing them to massless links. For example, a revolute-spherical massless link generates two kinematic constraint equations between adjacent bodies and allows four relative degrees of freedom. In this paper, to implement a massless link systematically in a computer program using the velocity transformation technique, the velocity transformation matrix of massless links is derived and numerically implemented. The velocity transformation matrix for a revolute-spherical massless link and a revolute-universal massless link are appeared as a 6$\times$4 matrix and a 6$\times$3 matrix, respectively. A massless link model in a suspension composite joint transmitting external forces is also developed and the numerical efficiency of the proposed model is compared to a conventional multibody model. For a massless link transmitting external forces, forces acting on links are resolved and transmitted to the attached points with a quasi-static assumption. Numerical examples are presented to verify the formulation.

Analyses of Stress Intensity Factors and Evaluation of Fracture Toughness in Adhesively Bonded DCB Joints (DCB 접착이음에 대한 응력세기계수의 해석 및 파괴인성의 평가)

  • Jeong, Nam-Yong;Lee, Myeong-Dae;Gang, Sam-Geun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.6 s.177
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    • pp.1547-1556
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    • 2000
  • In this paper, an evaluation method of fracture toughness to apply interfacial fracture mechanics was investigated in adhesively bonded double-cantilever beam (DCB) joints. Four types of adhesively bonded DCB joints with an interface crack were prepared for analyses of the stress intensity factors using boundary element method(BEM) and the fracture toughness test. From the results of BEM analysis and fracture toughness experiments, it is found that the stress intensity factor, K1 is a parameter driving the fracture of adhesively bonded joints. Also, the evaluation method of fracture toughness by separated stress intensity factors of mixed mode cracks was proposed and the influences of mode components for its fracture toughness are investigated in adhesively bonded DCB joints.

A magneto-thermo-viscoelastic problem with fractional order strain under GN-II model

  • Deswal, Sunita;Kalkal, Kapil Kumar;Sheoran, Sandeep Singh
    • Structural Engineering and Mechanics
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    • v.63 no.1
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    • pp.89-102
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    • 2017
  • In this work, we present a theoretical framework to study the thermovisco-elastic responses of homogeneous, isotropic and perfectly conducting medium subjected to inclined load. Based on recently developed generalized thermoelasticity theory with fractional order strain, the two-dimensional governing equations are obtained in the context of generalized magnetothermo-viscoelasticity theory without energy dissipation. The Kelvin-Voigt model of linear viscoelasticity is employed to describe the viscoelastic nature of the material. The resulting formulation of the field equations is solved analytically in the Laplace and Fourier transform domain. On the application of inclined load at the surface of half-space, the analytical expressions for the normal displacement, strain, temperature, normal stress and tangential stress are derived in the joint-transformed domain. To restore the fields in physical domain, an appropriate numerical algorithm is used for the inversion of the Laplace and Fourier transforms. Finally, we have demonstrated the effect of magnetic field, viscosity, mechanical relaxation time, fractional order parameter and time on the physical fields in graphical form for copper material. Some special cases have also been deduced from the present investigation.

The Genetic and Non-Genetic Aspects of Leg Weakness and Osteochondrosis in Pigs - Review -

  • Fukawa, K.;Kusuhara, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.1
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    • pp.114-122
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    • 2001
  • Leg weakness in pigs is one of the most serious problems in the pig industry. Leg weakness is responsible for an increase in the rate of culling of breeding pigs, which results in economic loss in the pig industry. Many researchers have investigated the cause of leg weakness, and that of osteochondrosis, in pigs, as well as in other mammals. For evaluating leg weakness, subjective scoring criteria have been applied, but the scoring systems varied widely. Subjective scoring systems have also been used in evaluating osteochondrosis lesions in leg joints. The lesions were scored optically, radiographically and histologically. Leg weakness and osteochondrosis are to some extent heritable traits. The heritability of leg weakness and joint lesion scores was found to range from 0.01 to 0.42. Leg weakness and osteochondrosis are associated with production traits (lean percentage and back fat depth). Nutritional aspects of leg weakness and osteochondrosis have also been extensively studied. Although the energy level of the diet may affect leg weakness and osteochondrosis, other nutritional factors seem to have very little effect. Confinement conditions also have an effect on leg weakness and osteochondrosis. Although studied extensively, the cause and etiology of leg weakness and osteochondrosis remain uncertain. It could be that there are multiple causes of leg weakness.

Structural Design and Experimental Investigation of A Medium Scale Composite Wind Turbine Blade Considering Fatigue life

  • Kong, C.D.;Bang, J.H.;Jeong, J.C.
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2002.04a
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    • pp.88-89
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    • 2002
  • The aims of this study is to realize the structural design for development of a medium scale E-glass/epoxy composite wind turbine blade for a 750KW class horizontal axis wind turbine system. In this study, the various load cases specified by the IEC61400-1 international specification and GL Regulations for the wind energy conversion system were considered, and a specific composite structure configuration which can effectively endure various loads such as aerodynamic and centrifugal loads, loads due to accumulation of ice, hygro-thermal and mechanical loads was proposed. In order to evaluate the structure, the structural analysis for the composite wind turbine blade were peformed using tile finite element method(FEM). In the structural design, the acceptable blade structural configuration was determined through the parametric studies, and the most dominant design parameters were confirmed. In the stress analysis using the FEM, it was confirmed that the blade structure was safe and stable in any various load cases Moreover the safety of the blade root joint with insert bolts, newly devised in this study, was checked against the design fond and the fatigue.

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Failure Behavior of Pin-jointed Carbon/Epoxy Composites using Acoustic Emission (음향방출법을 이용한 탄소섬유/에폭시 복합재의 핀 체결부 파괴거동)

  • Kim, Chan-Gyu;Hwang, Young-Eun;Yoon, Sung-Ho
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.520-522
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    • 2011
  • In this paper, the bearing strengths and fracture behaviors of the pin-jointed carbon fiber/epoxy composites were investigated through pin loading test. The composites were fabricated by a filament winding process, and two types of laminated patterns were considered. According to the results, type 1 pattern revealed a net-tension failure mode, whereas type 2 pattern exhibited a bearing failure mode. Also, acoustic emission energy of the type 2 pattern was higher than that of the type 1 pattern. Therefore, the type 2 pattern was found to be structurally safer than the type 1 pattern.

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STEPSTONE: An Intelligent Integration Architecture for Personal Tele-Health

  • Helal, Sumi;Bose, Raja;Chen, Chao;Smith, Andy;De Deugd, Scott;Cook, Diane
    • Journal of Computing Science and Engineering
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    • v.5 no.3
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    • pp.269-281
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    • 2011
  • STEPSTONE is a joint industry-university project to create open source technology that would enable the scalable, "friction-free" integration of device-based healthcare solutions into enterprise systems using a Service Oriented Architecture (SOA). Specifically, STEPSTONE defines a first proposal to a Service Oriented Device Architecture (SODA) framework, and provides for initial reference implementations. STEPSTONE also intends to encourage a broad community effort to further develop the framework and its implementations. In this paper, we present SODA, along with two implementation proposals of SODA's device integration. We demonstrate the ease by which SODA was used to develop an end-to-end personal healthcare monitoring system. We also demonstrate the ease by which the STEPSTONE system was extended by other participants - Washington State University - to include additional devices and end user interfaces. We show clearly how SODA and therefore SODA devices make integration almost automatic, replicable, and scalable. This allows telehealth system developers to focus their energy and attention on the system functionality and other important issues, such as usability, privacy, persuasion and outcome assessment studies.