• Proceedings of the KSR Conference
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• 1998.05a
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• pp.502-509
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• 1998

The scheme to reduce jerking phenomena in one push-pull type trainset was proposed. To simulate the jerking between coaches, dynamic analysis model was made. This model could analyze longitudinal dynamic behavior between locomotives and coaches caused by spring and damping characteristics of couplers and center pivots; characteristic curves of traction and braking. To validate the analysis results, tests were conducted in the same driving and braking condition. Comparison of longitudinal acceleration between simulation and test results shows a good agreement. To minimize the jerking phenomena, lots of dynamic simulations were conducted with varying driving/braking effort curve. From the results of simulations, an efficient and economic way to reduce jerking phenomena was found to be to reduce slope of tractive effort curve and synchronize braking time between locomotives and coaches. Test results show that this way could reduce the jerking Phenomena. To express jerkins Phenomena quantitatively, maximum peak to peak values of acceleration were used.

• Coupled systems mechanics
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• v.2 no.3
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• pp.215-230
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• 2013

This paper investigates the pull-in instability of functionally graded poly-SiGe micro-beams under the combined electrostatic and intermolecular forces and temperature change. The exponential distribution model and Voigt model are used to analyze the functionally graded materials (FGMs). Principle of virtual work is used to derive the nonlinear governing differential equation which is then solved using differential quadrature method (DQM). A parametric study is conducted to show the significant effects of material composition, geometric nonlinearity, temperature change and intermolecular Casimir force.

• The Journal of the Korea Contents Association
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• v.22 no.1
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• pp.224-239
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• 2022

Despite an impressive growth of online sales, the bricks-and-mortar bandwagon still remain high-profile in the realm of consumer channel switching behavior. Different from the existing research exploring the consumer switching behavior from the offline to the online retailer, this study is an effort to investigate why and when do consumers switch from the online to the offline channel by applying the push-pull-mooring framework. Thus, structural equation modeling and SPSS were used to test the established hypotheses. The results, as expected, show that both push factors (i.e., perceived risk and dissatisfaction) and pull factors (alternative attractiveness and perceived ownership) are positively related to a consumer's intention to switch from the online to the offline channel. Moreover, all of expected interactions between push factors and mooring factors (i.e., switching costs, variety seeking, and subjective norms), and between pull factors and mooring factors are supported, except for the interactions between push factors and switching costs as well as between pull factors and subjective norms. Finally, implications and limitations are discussed.

• The Journal of Information Systems
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• v.30 no.3
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• pp.65-91
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• 2021

Purpose In this study, we investigated the impact of perceived risk and switching costs on switching intention to cloud service based on PPM (Pull-Push-Mooring) model. Design/methodology/approach We focused on revealing the switching factors of the switching intention to the cloud services. The switching factors to the cloud services were defined as perceived risk consisting of performance risk, economic risk, and security risk, and switching costs consisting of financial and learning costs. On the PPM model, we defined the pull factors consisting of perceived usefulness and perceived ease of use, and the push factor as satisfaction of the legacy system, and the mooring factor as policy supports. Findings The results of this study as follows; (1) Among the perceived risk factors, performance risk has a negative effect on the ease of use of pull factors, and finally it was found to affect the switching intention to the cloud services. Therefore, cloud service providers need to improve trust in cloud services, service timeliness, and linkage to the legacy systems. And it was found that economic risk and security risk among the perceived risk factors did not affect the switching intention to the cloud services. (2) Of the perceived risk factors, financial cost and learning cost did not affect the satisfaction of the legacy system, which is a push factor. It indicates that the respondents are positively considering switching to cloud service in the future, despite the fact that the respondents are satisfied with the use of the legacy system and are aware of the switching cost to cloud service. (3) Policy support was found to improve the switching intention to cloud services by alleviating the financial and learning costs required for cloud service switching.

• Journal of the Korean Geotechnical Society
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• v.34 no.11
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• pp.5-19
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• 2018

The characteristics of the skin shear stress distribution for the fixed length of the ground anchor are extremely nonlinear and the engineering mechanisms are complex relatively. So it is difficult to design the anchors simulating the actual behavior by considering various soil conditions and nonlinear behavior. Due to these limits, constant skin shear stress distributions for the whole fixed length of the ground anchor are usually assumed in the design for the sake of convenience. In this study, to assess the pull-out behavior of the tension-type ground anchors, the in-situ pull-out tests in weathered-soil conditions were carried out. Based on the test results, the skin shear behaviors for the fixed length of tension-type ground anchors were established and the multi-linear slip shear model predicting this behavior and an analytical technique applying this model were proposed. From the similarity between the results of the in-situ pull-out tests and those of the analytical technique, the applicability and availability of the multi-linear slip shear model and the proposed analytical technique were verified. The maximum shear stress was developed at the start point of the fixed length acting with the smaller load than the maximum pull-out load but the minimum shear stress was developed at the start point of the fixed length and the maximum shear stress was developed at the point apart from the start point of the fixed length after the maximum pull-out load.

• Journal of Korea Trade
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• v.26 no.6
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• pp.20-40
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• 2022

Purpose - In recent times, the international trade environment has been changing rapidly, centering on the online market. In the post-COVID-19 era, small and medium-sized trading companies are facing the problem of not being properly provided with overseas market research, market trend analysis, and trade-related information. Cloud-based digital trade is being sought as an alternative to solve these problems; however, there is a lack of research on the intention to switch to digital trade among small and medium-sized trading companies. Therefore, this study empirically analyzes the intention to switch to digital trade based on the migration theory, and through this, attempts to identify each factor that affects the intention to switch to digital trade. Design/methodology - In this study, in order to identify factors influencing intention to switch to digital trade and innovation resistance of small and medium-sized trading companies, through previous research on migration theory and the PPM (Push, Pull, Mooring) model, each variable was selected for the purpose of the study. Based on this, a research model was established for the factors affecting switching to digital trade of small and medium-sized trading companies and empirically analyzed. In addition, considering the differences in the innovation propensity and maturity of information infrastructure of trading companies as the recipients of innovation, this study analyzes the moderating effect of the mooring effect and seeks ways to establish specific strategies according to the degree. Findings - As a result of empirical analysis, the pull effect was found to have the greatest influence on intention to switch to digital trade. However, the pull factor was found to have an effect on user resistance, and it was confirmed that it was a factor simultaneously inducing positive and negative consumption behaviors among users. In addition, it was found that the higher the company's innovation propensity, the higher the pull effect's influence on the intention to switch, and analysis showed that the push effect had no influence. In addition, companies with high information infrastructure maturity were expected to have a relatively high level of intention to switch compared to companies with low information infrastructure maturity, and the difference between the two groups was found not to be statistically significant. Originality/value - This study is a timely study in that it demonstrated the effect on the switching to cloud-based digital trade for small and medium-sized trading companies and that the cloud system related to digital trade is in full swing. There are academic implications in that it revealed that the pull effect is an important factor in the intention to switch to cloud service. Practical implications were presented in that small and medium-sized trading companies suggested ways to increase the value of the cloud system for switching to digital trade and a way to increase the switching ratio by minimizing the mooring effect. In addition, the study argues that active institutional support from the government is needed to activate cloud service.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.3
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• pp.61-82
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• 2020

This study was conducted to investigate the transformation of shopping behavior from showrooming to webrooming under multi-channel environment. By applying the push-pull-pooring (PPM) theory, we conceptualized the lack of utilitarian shopping value of showrooming as a push effect, the experiential shopping value of webrooming as a pull effect and the showrooming lock-in as mooring effect. Using structural equation model based on 276 sample data, we identified that the utilitarian shopping value of showrooming and the experiential shopping value of webrooming have a positive effect on the intention of webrooming, and that the showrooming mooring had a negative effect on the intention of webrooming.

• The Journal of the Acoustical Society of Korea
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• v.19 no.4
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• pp.107-114
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• 2000

This work is aimed to develop a new type of the Push-Pull ultrasonic transducer that can provide higher sound pressure level and simpler internal structure than conventional types. The driving part of the newly designed transducer is positioned in the middle of the cylinder, and its optimum geometry is determined by using the FEM package, ANSYS. Through FEM model analysis, the effects of all of its geometrical variables such as transducer length, transducer radius, and the edge shape of the end cap have been examined, and the results have led to the optimum geometry. The newly designed transducer has been found to give better performance than that of traditional ones.

• Asia pacific journal of information systems
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• v.8 no.3
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• pp.181-194
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• 1998

The inability of the management information systems (MIS) field to progress as a scientific discipline has been attributed to the lack of systematic research and a cumulative tradition, an identity crisis, and the poverty of scientism. While research on the status of MIS is very important in order to enhance the field as a scientific discipline, few have investigated this issue. Following Thomas Kuhn's idea of paradigm, this paper studies other fields to investigate when they progressed, when they did not, and why. After research paradigm was broken down into technology-push and demand-pull types, a model on the science life cycle was developed in an effort to explain the path how a science has progressed. A test of this model in the fields of physics and chemistry with an old historial background reveals that the scientific progress in the area of demand-pull is more desirable if this progress turns out to be in the right direction. An application of the model to the MIS field shows that the research paradigm in this field is mainly of technology-push. In order to shift this paradigm toward the demand-pull area, this paper suggests the research on the relationship among MIS subfields and the adoption of appropriate reference disciplines.

• Journal of the Korean Geotechnical Society
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• v.33 no.11
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• pp.35-43
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• 2017

In this study, the pull-out resistance behavior of the anchor with the bump type resistors at the anchor body was experimentally investigated. In the model tests, the pull-out resistance was measured by pulling out the anchor at a constant speed. Anchor body was installed in the center of the circular sand tank. Pull-out tests were conducted for 10 conditions. The anchor type (existence of the resistor), the friction conditions of the anchor body surface ($1/3{\phi}$, $2/3{\phi}$, ${\phi}$), the bump type resistor set number (1set, 2set, 4set), and the height of resistors (0.05d, 0.10d, 0.20d) were varied. The load-displacement relationship for each conditions was measured during the pull-out tests at a constant speed (1 mm/min). Maximum pull-out length was 80 mm. As a result, the pull-out behavior of the friction type anchor and the expansion type anchor was different. As the number of resistor increased, the maximum pull-out resistance increased and the residual pull-out resistance ratio increased significantly, which were at 171~591 percent larger than that of the friction type anchor.