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141.
This paper seeks to improve our understanding of passengers’ behavioral intention by proposing an integrated framework from
the attitudinal perspective. According to the literature in marketing research, we establish a causal relationship model that
considers “service quality-satisfaction-behavioral intentions” paradigm, perceived value theory, and switching barrier theory.
Exploring passengers’ behavioral intention from satisfaction and perceived value help to understand how passengers are attracted
by the company, while switching barriers assist in realizing how passengers are “locked” into a relationship with the current
company. Furthermore, in order to capture the nature of service quality, we adopt a hierarchical factor structure which serves
service quality as the higher-order factor. In this study, coach industry is selected as our research subject. The empirical
results, as hypothesized, show that all causal relationships are statistically significant, and perceived value us the most
important predictor of satisfaction and passengers’ behavioral intention. In conclusion, the managerial implications and suggestions
for future research are discussed. 相似文献
142.
Statistical and dynamical analyses of propagation mechanisms of solitary internal waves in a two-layer stratification 总被引:2,自引:0,他引:2
Chen-Yuan Chen 《Journal of Marine Science and Technology》2011,16(1):100-114
The blocking effect of submarine ridges on the propagation of internal solitary waves (ISWs) over the topography of the seabed
results in the fission of the solitary waves that accompany the generation of reflected and transmitted waves. In this study,
multivariate analysis of variance (MANOVA) is used to investigate the inseparable relationship between the transmission and
reflection. An examination of the error sums of squares and cross-products (SSCP) matrix and the correction matrix shows that
the correlation between the transmission (at/ai) and reflection coefficients (ar/ai) is quite low (0.284). Moreover, from
multivariate testing, including Pillai’s trace, Wilks’ lambda, Hotelling’s trace and Roy’s largest root, we conclude that
the ridge height has a large effect (η = 0.456) on both the amplitude of the transmitted and reflected waves, as well as large (η = 0.411) and very large (η = 0.469) effects on the amplitudes of the transmitted and reflected waves, respectively. In conclusion, the results in the
present study highlight the importance of the role played by ridge height in coherent ISW transmission and reflection during
oceanic wave–ridge interactions. 相似文献
143.
Hirotada Hashimoto Naoya Umeda Akihiko Matsuda 《Journal of Marine Science and Technology》2011,16(4):448-461
The new intact stability criteria which are under development at the International Maritime Organization (IMO) are required
to cover a broaching phenomenon, well known as a great threat to high-speed vessels which can lead to capsizing. Some reports
exist which demonstrate that their numerical models can predict a highly nonlinear phenomenon of broaching. However, additional
validation studies are needed for unconventional vessels, in addition to conventional ones, to develop direct stability assessment
methods for the new intact stability criteria. In this research, we selected as the subject ship a wave-piercing tumblehome
vessel with twin screws and twin rudders, a design expected to be one of a new generation of high-speed monohull ships. Firstly,
a series of captive model tests were conducted to measure the resistance, the manoeuvring forces, the wave-exciting forces,
the heel-induced hydrodynamic forces, and the roll restoring variation for the unconventional tumblehome vessel. Secondly,
the existing mathematical model which had been developed for broaching prediction of conventional vessels with a single propeller
and a single rudder was extended to unconventional vessels with twin propellers and twin rudders. Finally, comparisons between
numerical simulations and the existing free running model experiments were conducted. As a result, it was demonstrated that
fair quantitative prediction of broaching is realised when the rudder force variation, the roll restoring variation and the
heel-induced hydrodynamic force for large heel angles are taken into account. 相似文献
144.
Kazuhiro Iijima Kazuhiro Kimura Weijun Xu Masahiko Fujikubo 《Journal of Marine Science and Technology》2011,16(4):379-389
Dynamic collapse behavior of a ship’s hull girder in waves is investigated; post-ultimate strength behavior is the focus.
Firstly, a simulation method is proposed. Assuming that a plastic hinge is formed during the collapse of the hull girder,
the whole ship is modeled as two rigid bodies connected amidship via a nonlinear rotational spring. The post-ultimate strength
behavior, such as the reduction of load carrying capacity due to buckling and yielding, is reflected in the model. Hydrodynamic
loads are evaluated by using nonlinear strip theory to account for the effect of large plastic deformations on the loads.
A scaled model for validation of the simulation is designed and fabricated. Then a series of tank tests is conducted using
the scaled model to validate the simulation results. Post-ultimate strength behavior characteristics in waves are clarified
by using the numerical and tank test results. It is shown that the hull girder collapses rapidly after reaching ultimate strength,
and then the plastic deformation grows until unloading starts at the collapsed section. Finally, several parametric dependencies
of the extent of the collapse behavior are discussed based on a series of the simulations. 相似文献
145.
This paper presents a numerical analysis of the dynamic transient behaviors of undersea cables. In this numerical study, the
governing equations based on Euler-Bernoulli beam theory are adopted, and they can satisfy many applications no matter what
the magnitude of the cable tension is. The nonlinear coupled equations are solved by a popular central finite difference method,
and the numerical results of transient behaviors are presented when several kinds of surrounding conditions, such as different
towing speeds of surface vessel, different currents and waves with various frequencies and amplitudes, are exerted. Then a
detailed comparison of the results, including the upper end tension and cable shape in time-domain, is made under the above
external excitations, and finally the possible reasons for these are further explained. 相似文献
146.
Interfacial heat transfer is a key issue in many solidification processes. In the paper, a novel experimental apparatus has
been designed and on this basis, the instantaneous interfacial heat transfer between molten steel or solidified shell and
copper substrate during the first 0.2 s has been studied. The investigated parameters include melt superheat, substrate temperature
and surface roughness. The results show that the peak value of the interfacial heat flux in the first stage of liquid/solid
contact increases with melt superheat and changes slightly with substrate temperature and surface roughness. The interfacial
heat flux in the stage of solid/solid contact has a similar trend of slow decrease in most conditions. 相似文献
147.
The numerous construction projects in China provide the best environment for the development of information technology applied
in building design. Various commercial CAD/CAE software applications are purchased by design firms for multi-disciplinary
design tasks. However, researches on integration and interoperability are seldom considered. This study pursues a breakthrough
point of integration in the architectural and structural domains and expects further development in other aspects. A central
building information modeling (BIM) framework based on the industry foundation classes (IFC) is proposed to handle the data
exchange between IFC-compatible architectural models and structural models. A central XML(extensible markup language)-based
unified finite element model (FEM) is proposed for model conversion among various commercial structural CAE software applications.
In addition to bidirectional data interfaces among IFC-based BIM, XML-based FEM and various commercial FEMs, some other components
such as visualization, calculation and model editing/check are also equipped into the prototype system. 相似文献
148.
In the field of 3D model matching and retrieval, an effective method for feature extraction is spherical harmonic or its mutations,
and is acted on the spherical images. But the obtainment of spherical images from 3D models is very time-consuming, which
greatly restrains the responding speed of such systems. In this paper, we propose a quantitative evaluation of the whole process
and give a detailed two-sided analysis based on the comparative size between pixels and voxels. The experiments show that
the resultant optimized parameters are fit for the practical application and exhibit a satisfactory performance. 相似文献
149.
This paper presents a full-scale solution to the detection of the traffic data using laser device. Range images, gathered
by a particular laser camera, are used in the multi-threshold segmentation. The multi-threshold segmentation is based on the
height of the moving objects. In order to get the precise height of the moving objects, mapping of the original terrain is
performed on the first step. On each layer, the clustering algorithm called iteration-self organizing data analysis techniques
algorithm (ISODATA) is conducted afterwards. Kalman filtering technique is applied to recognize and track the moving objects.
Extensive experiments show that these algorithms are effective in object recognition and tracking, as well as robust in the
applications. 相似文献
150.
The development of an innovative H
∞ controller for looper and tension control in hot strip finishing mills is traced based on approximately linearized model.
This solution has been considered thanks to its well-known robustness and simplicity characteristics concerning disturbances’
attenuation. The controller is designed based on an optimal problem with linear matrix inequality (LMI) constraints, and the
problem is solved by the mincx function of Matlab LMI Toolbox. Simulation results show the effectiveness of the proposed controller
compared with conventional ones. 相似文献