• Journal of Hydrogen and New Energy
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• v.34 no.6
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• pp.641-649
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• 2023

This study analyzes the cool-down process of liquid hydrogen storage tanks, which have advantages in terms of large-capacity transfer, storage, and utilization as hydrogen demand increases. A hydrogen liquefaction plant is selected for analysis and an efficient tank cooling method is sought by comparing the time required for the cool-down process with the gas consumption in connection with the gassing-up process required for the operation of the liquid hydrogen storage tank. The results of this study can be referred to in the operation process after the initial start-up and maintenance of the hydrogen liquefaction plant.

• Journal of the Korea Society of Computer and Information
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• v.29 no.7
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• pp.221-229
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• 2024

As the level of economic development increases, interest in human capital is also increasing. This paper estimates and compares innovative human capital by region for 31 regions in China between 2002 and 2019. The innovative human capital in this paper consists of education-type human capital, thesis-type human capital, and patent-type human capital. In particular, unlike previous studies, this study assumes that the weight of patent-type human capital and paper-type human capital is higher than that of education-type human capital. This is because patents and thesis will have a relatively greater impact on a region's innovation capacity than simple education background. The analysis results of this paper can be summarized in three points. First, China's regional innovative human capital shows regional disparities. Second, innovative human capital by region is changing dynamically. Third, regional concentration is accelerating, especially in Beijing, Shanghai, Guangdong, and Jiangsu. Therefore, the results of this paper emphasize the importance of the role of innovative human capital in regional economic development.

• Structural Engineering and Mechanics
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• v.66 no.3
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• pp.399-409
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• 2018

This paper demonstrates the potential application of machine learning algorithms for approximate prediction of the load and deflection capacities of the novel type of Laced Steel Concrete-Composite (LSCC) beams proposed by Anandavalli et al. (Engineering Structures 2012). Initially, global and local responses measured on LSCC beam specimen in an experiment are used to validate nonlinear FE model of the LSCC beams. The data for the machine learning algorithms is then generated using validated FE model for a range of values of the identified sensitive parameters. The performance of four well-known machine learning algorithms, viz., Support Vector Regression (SVR), Minimax Probability Machine Regression (MPMR), Relevance Vector Machine (RVM) and Multigene Genetic Programing (MGGP) for the approximate estimation of the load and deflection capacities are compared in terms of well-defined error indices. Through relative comparison of the estimated values, it is demonstrated that the algorithms explored in the present study provide a good alternative to expensive experimental testing and sophisticated numerical simulation of the response of LSCC beams. The load carrying and displacement capacity of the LSCC was predicted well by MGGP and MPMR, respectively.

• Steel and Composite Structures
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• v.21 no.3
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• pp.537-551
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• 2016

A new type of composite beam which consists of a wide flange steel shape beam and an innovative type of composite slab was introduced. The composite slab is composed of concrete slab and normal flat steel plates, which are connected by perfobond shear connectors (PBL shear connectors). This paper describes experiments of two large-scale specimens of that composite beam. Both specimens were loaded at two symmetric points for 4-point loading status, and mechanical behaviors under hogging and sagging bending moments were investigated respectively. During the experiments, the crack patterns, failure modes, failure mechanism and ultimate bending capacity of composite beam specimens were investigated, and the strains of concrete and flat steel plate as well as steel shapes were measured and recorded. As shown from the experimental results, composite actions were fully developed between the steel shape and the composite slab, this new type of composite beams was found to have good mechanical performance both under hogging and sagging bending moment with high bending capacity, substantial flexure rigidity and good ductility. It was further shown that the plane-section assumption was verified. Moreover, a design procedure including calculation methods of bending capacity of this new type of composite beam was studied and proposed based on the experimental results, and the calculation methods based on the plane-section assumption and plastic theories were also verified by comparisons of the calculated results and experimental results, which were agreed with each other.

• Structural Engineering and Mechanics
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• v.83 no.4
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• pp.415-433
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• 2022

Eighteen (18) (120×300×2200 mm) beams were prepared and tested to evaluate the shear strength of Glass Fiber Reinforced Concrete (GFRC) beams with no shear reinforcement, and evaluate the effectiveness of various innovative strengthening systems to increase the shear capacity of the GFRC beams. The test variables are the amount of discrete glass fiber (0.0, 0.6, and 1.2% by volume of concrete) and the type of longitudinal reinforcement bars (steel or GFRP), the strengthening systems (externally bonded (EB) sheet, side near-surface mounted (SNSM) bars, or the two together), strengthening material (GFRP or steel) links, different configurations of NSM GFRP bars (side bonded links, full wrapped stirrups, side C-shaped stirrups, and side bent bars), link spacing, link inclination angle, and the number of bent bars. The experimental results showed that adding the discrete glass fiber to the concrete by 0.6%, and 1.2% enhanced the shear strength by 18.5% and 28%, respectively in addition to enhancing the ductility. The results testified the efficiency of different strengthening systems, where it is enhanced the shear capacity by a ratio of 28.4% to 120%, and that is a significant improvement. Providing SNSM bent bars with strips as a new strengthening technique exhibited better shear performance in terms of crack propagation, and improved shear capacity and ductility compared to other strengthening techniques. Based on the experimental shear behavior, an analytical study, which allows the estimation of the shear capacity of the strengthened beams, was proposed, the results of the experimental and analytical study were comparable by a ratio of 0.91 to 1.15.

• 한국벤처창업학회:학술대회논문집
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• 2007.04a
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• pp.35-64
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• 2007

Despite the tremendous efforts to boost them, domestic SMEs lack competitive power and it intensifies bipolarization between the conglomerates and SMEs. Furthermore, degree of industry-academy collaboration still falls far behind of that of developed countries even with government' s various policies and continuous increase in investment to strengthen the SMEs' technology innovation capability. Although many internal factors are suggested to affect technological performance, focus of existing studies has been restricted to immediate impact of industry-academy collaboration on technology innovation and it is not known how internal factors are related. This research conducts empirical analysis on the impact of industry-academy collaborations and absorptive capacity on technological performance in Korean SMEs. Sample frame is SMEs with more than five employees located in the nation wide industrial complex and 1,077 questionnaires are collected with the help of Korea Industrial Complex Corporations. 940 sample data excluding those with insufficient response are used in analysis. Multiple regression analysis revealed that the industry-academy collaborations and innovative HRM system, on important dimension of absorptive capacity, are positively correlated to technological performance. Furthermore, there exists a positive interaction effect between industry-academy collaborations and innovative HRM system. These findings make contributions to the formation of SME innovation policy and management. When funding industry-academy collaborations, government should consider SMEs' internal effort for innovation, that is, the possession of innovative HRM system, as well as firm's technology capability. Also, as technological performance cannot be achieved simply with R&D investment, both quantitative and qualitative assessment of SMEs' technological capability should be done to evaluate the candidate SMEs. As for management, it is important for SMEs with limited internal resources and capabilities to fully employ external resources to achieve higher technological performance. The development of innovative HRM system will be particularly helpful not only for internal R&D, but also for adoption of technology and knowledge from outside.

• International Journal of Concrete Structures and Materials
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• v.3 no.2
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• pp.119-126
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• 2009

This paper provides a brief summary of the performance of an innovative slip hardening twisted steel fiber in comparison with other fibers including straight steel smooth fiber, high strength steel hooked fiber, SPECTRA (high molecular weight polyethylene) fiber and PVA fiber. First the pull-out of a single fiber is compared under static loading conditions, and slip rate-sensitivity is evaluated. The unique large slip capacity of T-fiber during pullout is based on its untwisting fiber pullout mechanism, which leads to high equivalent bond strength and composites with high ductility. Due to this large slip capacity a smaller amount of T-fibers is needed to obtain strain hardening tensile behavior of fiber reinforced cementitious composites. Second, the performance of different composites using T-fibers and other fibers subjected to tensile and flexural loadings is described and compared. Third, strain rate effect on the behavior of composites reinforced with different types and amounts of fibers is presented to clarify the potential application of HPFRCC for seismic, impact and blast loadings.

• World Technopolis Review
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• v.4 no.3
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• pp.157-167
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• 2015

Innovation system is a framework concept that can be classified in many ways, namely-national, regional, sectoral and technological. Regardless of classification, all these systems have some common features and characteristics as a system. Before the innovation system concept, Mongolia developed and implemented a system to maintain nation's capacity to acquire, absorb and disseminate technologies like other countries. There were two important practices in the system development. Firstly, Mongolia modified and implemented a system "ShBOS" (meant "Invention and Innovative Idea System") that met its unique features to create innovative culture in the nation. Secondly, newly emerged ICT sector was quickly scaled up to be able to export technological products. The main objective of this article is to study modern experience of developing the national innovation system in Mongolia, assess current state of the system, innovation awareness and readiness, and carry out recommendations on its improvement with particular focus on the capacity of ICT sector as a pilot sector. The paper suggests that the above mentioned two achievements can be applied for developing the national innovation system through technological innovation system approach.

• Steel and Composite Structures
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• v.35 no.4
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• pp.509-525
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• 2020

Steel-concrete composite slabs with profiled steel sheeting are widely used in the execution of floors in steel and composite buildings. The rapid construction process, the elimination of conventional replaceable shuttering and the reduction of temporary support are, in general, considered the main advantages of this structural system. In slabs with the spans currently used, the longitudinal shear resistance commonly provided by the embossments along the steel sheet tends to be the governing design mode. This paper presents an innovative reinforcing system that increases the longitudinal shear capacity of composite slabs. The system is constituted by a set of transversal reinforcing bars crossing longitudinal stiffeners executed along the upper flanges of the steel sheet profiles. This type of reinforcement takes advantage of the high bending resistance of the composite slabs and increases the slab's ductility. Two experimental programmes were carried out: a small-scale test programme - to study the resistance provided by the reinforcing system in detail - and a full-scale test programme to test simply supported and continuous composite slabs - to assess the efficacy of the proposed reinforcing system on the global behaviour of the slabs. Based on the results of the small-scale tests, an equation to predict the resistance provided by the proposed reinforcing system was established. The present study concludes that the resistance and the ductility of composite slabs using the reinforcing system proposed here are significantly increased.

• Journal of Digital Convergence
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• v.8 no.2
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• pp.29-42
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• 2010

To improve the performance of R&D investments, government has taken great efforts for advancing the structure and process in R&D systems. However, due to the drastic internal/external changes in the technological environment and the steady increase of investment scale, the necessity for a innovative approach which accomplishes returns to scale through the utilization of various external resources is emerging. In this regard, open innovation approach can minimize the possibility of government failures by strengthening the absorptive capacity of external resources and enhancing the cooperation and participation of diverse innovative participants within the R&D system. This paper evaluates the previous researches and government policies concerning the performances of government R&D investments, and presents the connectivity between open innovation and its possible contribution to the improvement of R&D investment performances.