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1.
Lai-Ying Leong Teck-Soon Hew Keng-Boon Ooi Alain Yee Loong Chong Voon-Hsien Lee 《Information & Management》2021,58(2):103416
This paper examines what influences trust in mobile social commerce environment. Drawing on trust-based acceptance model (i.e. cognitive and emotional trust) and online review features (i.e. profile photo, linguistic style, and reported experience), we examine how these factors affect trust in mobile social commerce. Hypotheses were tested using survey data. The results of our model showed that there are significant influences of profile photo, reported experience, cognitive, and emotional trust towards trust in ms-commerce. This work contributes to existing literature by examining the roles of previous trust in mobile payments and online reviews on trust in mobile social commerce. 相似文献
2.
Boon Tiong Tan Siou Teck Chew Mook Seng Leong Ban Leong Ooi 《Microwave Theory and Techniques》2003,51(8):1906-1910
A dual-mode ring bandpass filter with two pairs of capacitors has been designed. The capacitors are used to control the location of the even- and odd-mode frequencies independently, allowing weak coupling for narrow-band filter design with realizable capacitance values. Theoretical expressions have been derived for these frequencies. A 4% bandwidth bandpass filter centered at 1.9 GHz was designed and tested with good agreement between theoretical and measured results. 相似文献
3.
The authors present two-year statistics on the rainfall attenuation of 21.225 GHz vertically polarized CW microwave signals in Singapore. The CCIR recommendation is found to underestimate the microwave specific attenuation (dB/km) per path average rain rate (mm/h) as well as the accumulated time of attenuation exceeding preset levels. A negative exponential raindrop size distribution based on spherical droplets is constructed from the measured data 相似文献
4.
Wen-Yan Yin Le-Wei Li Tat-Soon Yeo Mook-Seng Leong Pang-Shyan Kooi 《Electromagnetic Compatibility, IEEE Transactions on》2002,44(2):329-337
The direct integral equation is formulated for describing the current on the multiple perfectly conducting strips in cylindrical geometries for an E-polarization plane wave of normal incidence. By using the Galerkin's method, the surface currents on the conducting strips are expanded in the form of a series of Chebyshev polynomials of the first kind, while the unknown expanding coefficients are solved by a set of matrix equations of finite order with a fast convergence rate and a high accuracy. Furthermore, numerical results are presented to demonstrate the variation of the penetrated near-zone field in the presence of one, two, three, four and six cylindrical apertures, and the hybrid effects of both aperture number and aperture angular widths on the penetrated fields are investigated in detail 相似文献
5.
Eng Leong Tan Ding Yu Heh 《Microwave and Wireless Components Letters, IEEE》2008,18(5):296-298
This letter presents an unconditionally stable alternating direction implicit finite-difference time-domain (ADI-FDTD) method with fourth order accuracy in time. Analytical proof of unconditional stability and detailed analysis of numerical dispersion are presented. Compared to second order ADI-FDTD and six-steps SS-FDTD, the fourth order ADI-FDTD generally achieves lower phase velocity error for sufficiently fine mesh. Using finer mesh gridding also reduces the phase velocity error floor, which dictates the accuracy limit due to spatial discretization errors when the time step size is reduced further. 相似文献
6.
This paper presents a new computerized procedure for dealing with the design of horizontal ground heat exchangers (HGHE). The computer program is based on the transient model of coupled nonlinear partial differential equations governing heat and mass flow in soils. The model is two-dimensional and delineates the operation of ground heat storage with the HGHE and such phenomena as freezing/thawing and drying/rewetting of soil moisture. Comprehensive climatological data, such as ambient temperature, solar radiation, wind velocity, rainfall, snowfall, snow characterstics, and water vapour pressure is used to simulate conditions at the ground surface over any required length of time. The package can be applied to any geographical location by changing climatic and soil data input. The designer has the possibility of selecting any of 12 types of soils from sand to clay, 12 commercial heat pumps, nine different configurations of the HGHE, 16 plastic pipes for ground coils, and 13 ground coil fluids. The program, however, does not calculate the length of the HGHE but it evaluates the thermodynamic performance of a ground heat pump system and provides comprehensive data on thermal and hydraulic conditions in ground heat storage. The length of the ground heat exchanger is obtained from a line source theory model or from site dimensions and pipe spacing. Computed results for ground heat exchanger operation correlate fairly well with experimental data. Simulation of temperature and moisture content in the ground for natural conditions (no heat extraction/deposition) showed a fair agreement with field data. The entire computer program is user-friendly, interactive, menu-driven, and written in FORTRAN 77. 相似文献
7.
The Yersinia pseudotuberculosis invasin protein is a 986-amino acid protein that promotes bacterial penetration into mammalian cells by avidly binding multiple beta 1-chain integrins. A 192-amino acid carboxyl-terminal domain of invasin was previously shown to be sufficient for binding. Evidence is presented here that a 76-amino acid disulfide loop in the integrin binding domain of invasin is required for invasin-mediated cell binding and entry. Bacterial mutants that were altered at either of 2 cysteine residues in the binding domain of invasin were completely defective for entry. Purified invasin protein derivatives altered at either of these cysteines, in contrast to the wild-type invasin, did not promote either cell binding or penetration. Analysis of proteolytic products of invasin in the presence or absence of reducing agent provided evidence of an intra-chain disulfide bond near the carboxyl terminus of the protein. Alkylation of invasin derivatives with [3H]iodoacetate indicated that these 2 cysteines were normally disulfide-bonded. A treatment that resulted in the maximal reduction of the disulfide bond also resulted in maximal loss of cell attachment activity. These results indicate that the 76-amino acid disulfide loop at the carboxyl terminus of invasin is required for recognition by integrins. 相似文献
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