• Advances in aircraft and spacecraft science
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• v.5 no.3
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• pp.335-348
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• 2018

The structural dynamics (SD) behavior of Elastic Flapping Wings (EFWs) is investigated analytically as a novel approach in EFWs analysis. In this regard an analytical SD solution of EFW undergoing a prescribed rigid body motion is initially derived, where the governing equations are expressed in modal space. The inertial forces are also analytically computed utilizing the actuator induced acceleration effects on the wing structure, while due to importance of analytical solution the linearity assumption is also considered. The formulated initial-value problem is solved analytically to study the EFW structural responses, where the effect of structure-actuator frequency ratio, structure-flapping frequency ratio as well as the structure damping ratio on the EFW pick amplitude is analyzed. A case study is also simulated in which the wing is modeled as an elastic beam with shell elements undergoing a prescribed sinusoidal motion. The corresponding EFW transient and steady response in on-off servo behavior is investigated. This study provides a conceptual understanding for the overall EFW SD behavior in the presence of inertial forces plus the servo dynamics effects. In addition to the substantial analytical results, the study paves a new mathematical way to better understanding the complex role of SD in dynamic EFWs behavior. Specifically, similar mathematical formulations can be carried out to investigate the effect of aerodynamics and/or gravity.

• Computational Structural Engineering
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• v.36 no.1
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• pp.10-14
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• 2023

• Geomechanics and Engineering
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• v.8 no.6
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• pp.769-781
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• 2015

The skin friction of a pile foundation is important and essential for its design and analysis. More attention has been given to the softening behaviour of skin friction of a pile. In this study, to investigate the load-transfer mechanism in such a case, an analytical solution using a nonlinear softening model was derived. Subsequently, a load test on the pile was performed to verify the newly developed analytical solution. The comparison between the analytical solution and test results showed a good agreement in terms of the axial force of the pile and the stress-strain relationship of the pile-soil interface. The softening behaviour of the skin friction can be simulated well when the pile is subjected to large loads; however, such behaviour is generally ignored by most existing analytical solutions. Finally, the effects of the initial shear modulus and the ratio of the residual skin friction to peak skin friction on the load-settlement curve of a pile were investigated by a parametric analysis.

• Journal of the Korea Society of Computer and Information
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• v.23 no.12
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• pp.123-129
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• 2018

The purpose of this paper is to draw a conclusion on the impact of intermediate software on enterprise results. In this paper, product innovation and product reliability are especially used as analytical factors. An exploratory analytical study is conducted on the competitiveness of intermediate software, in the hope of gaining a new understanding of the competitiveness of intermediate software. Data are analyzed using such quantitative analytical tools as SPSS and AMOS. Using reliability analysis, validity analysis and structural equation model analysis, the final results are achieved. According to the analysis results, we can draw the following conclusions: the competitiveness of intermediate software has a positive impact on the innovation of software products. The competitiveness of intermediate software doesn't have a positive impact on the reliability of software products. Product innovation has a positive impact on enterprise results. Product reliability also has a positive impact on enterprise results. By analyzing the conclusions, we can make certain suggestions and draw implications on the competitiveness of China's software industry.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.6
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• pp.679-687
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• 2003

In this study, we investigated the analytical techniques to quantify the ambient concentration of hydrogen sulfide (H$_2$S) in air at ppt concentration level. For this purpose, an on-line GC analytical system equipped with both pulsed-flame photometric detector (PFPD) and thermal desorption unit (TDU) was investigated by collecting ambient air samples. The results of our study generally indicated that calibration conditions of GC system is highly sensitive to affect the accuracy of the analytical technique. Most importantly. we found that the use of different matrices in the the preparation stage of working standards was sensitive to control the overall performance of this technique. The calibration of our analytical system was tested by the two types of working standard (prepared by mixing either with high purity $N_2$ or with the ambient air). According to this test, the latter represented more efficiently the detecting conditions of actual air samples. The peak occurrence patterns of both air samples and standards (prepared by mixing with ambient air) were altered in a similar manner as the function of the loaded volume; however, it was not the case for the $N_2$-mixed standards. Results of our study suggest that detection of H$_2$S is highly different from other sulfides and that its quantification requires minimiaing interfering effects of non -pure substance (like water vapor) and (either sorptive or destructive) loss effects.

• The Journal of Economics, Marketing and Management
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• v.6 no.1
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• pp.9-16
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• 2018

Purpose - Benefit delay type services have a characteristic of benefit delay that does not immediately appear at the time of delivery of service. Due to a characteristic of benefit delay, the customer's participation in the service delivery system is hindered, and the quality of service declines. As a result, customer satisfaction would be reduced. The purpose of this study is to construct an analytical framework to analyze a mechanism that promotes customer participation in benefit delay type services. Research design, data, and Methodology - Existing research has considered only the performance of service companies to enhance the quality of service and customer satisfaction. This study focused on customer participation as a factor affecting the quality of service and customer satisfaction and attempted to construct an analytical framework based on a theoretical perspective of motivational research. Results - By adopting the motivation theory, this research derived three concepts, the possibility of gaining benefits, the emotional experience, and the desire of benefit. And motivation is created when the three factors interact with each other. Conclusions - This paper has constructed an analytical framework for analyzing factors that promote customer participation in the benefit delay service and finally has proposed case study for further research.

• Korean Institute of Interior Design Journal
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• v.27 no.2
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• pp.128-142
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• 2018

This study is to analyze a case of US Bravo TV program, Interior therapy with Jeff Lewies, based on analytical psychology by Carl Jung, to understand characteristics of interior therapy in psycho-therapeutic viewpoint. Case study among descriptive observation approaches was chosen as a study method while the study range was set as 8 episodes in 2012 and 8 episodes in 2013. As a result of study, future application of therapy to domestic interior design was suggested as 3 types the following; a) Paranoid and storage disorder type that pursues space design by horizontal elements with a sense of comfortable, starting from throwing things away, and suggests whiteness based on desire to be cleaned; b) Individual taste type starting from give and take between members and recognizing one another. e.g., aligning the U-shaped sofa and giving a sense of comfort by using the achromatic colors; and c) Workroom type involved with the face-to-face type of space design and arrangement of mild grey and brown colors. Finally, this study has its significance in suggesting the direction for new occupational clusters in the field of domestic space design (interior, architecture, environment design, etc.), which could be utilized as a basic data for training program development to foster interior therapy professionals.

• Tribology and Lubricants
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• v.40 no.1
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• pp.1-7
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• 2024

Ball bearings are a major component of mechanical parts for transmitting rotation. Compared to tapered roller bearings, ball bearings offer less rolling resistance, which leads to reduced heat generation during operation. Because of these characteristics, ball bearings are widely used in electric vehicles and machine tools. The design of ball bearing cages has recently emerged as a major issue in ball bearing design. Cage design requires pre-verification of performance using theoretical or experimental formula or computational fluid dynamics (CFD). However, CFD analysis is time-consuming, making it difficult to apply in case studies for design decisions and is mainly used in performance prediction following design confirmation. To use CFD in the early stages of design, main-taining analytical accuracy while reducing the time required for analysis are necessary. Accordingly, this study proposes a laminar steady-state segment CFD technique to solve the problem of long CFD analytical times and to enable the use of CFD analysis in the early stages of design. To verify the reliability of the CFD analysis, a bearing drag torque test is performed, and the results are compared with the analytical results. The proposed laminar steady-state segment CFD technique is expected to be useful for case studies in bearing design, including cage design.

• Proceedings of the Korean Geotechical Society Conference
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• 1994.03a
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• pp.19-30
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• 1994

This paper reports a case study of aboutment displacement and pavement settlement observed at the construction site for highway bridges. The emphasis was on quantifying the horizontal deflections of about and pavement settlement on the backfill surface. It is shown that in soft clay, bridge aboutments on pile foundations are subjected to lateral earth pressures due to lateral soil movement. Based on the results analyzed, the earth pressure was predicted by deflection shape of piles based on the results of a numerical analysis and an analytical study. Also, the long term settlement of soil below pavement was estimated.

• Asian Journal of Innovation and Policy
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• v.7 no.2
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• pp.235-286
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• 2018

The aim of paper is to develop an alternative framework for the study of technological innovation systems. In contrast with conventional literature, this analytical framework is designed for entrepreneurs, i.e. actors, at the micro level rather than policy-makers at the meso or macro level. Herein, the entrepreneurial innovation system is conceptually refined by synthesizing knowledge regarding technological innovation and innovation systems. Drawing upon the intrinsic technological identity essential for innovation, the entrepreneurial innovation system is shown to involve three core changes in terms of technology, organization and market, and their couplings within its internal boundary over time. This analytical framework also takes into account the fact that the innovation system is influenced by and copes with the external environment during its evolution. Moreover, the framework of the entrepreneurial innovation system considers the recent trend of sustainable development. The technical and socio-economic characteristics of a nuclear powersystem are studied empirically to articulate an analytical framework that should be very useful for technological innovation in other energy systems by reflecting their unique features.