743 research outputs found

    Solving the Interpretational-Confounding and Interpretational-Ambiguity Problems of Formative Construct Modeling in Behavioral Research: Proposing a Two-Stage Fixed-Weight Redundancy Approach

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    Recently, information systems research has devoted increasing attention to formative measurements. However, current approaches to modeling formative constructs have potential validity problems and thus limited applicability. Here, we highlight two major problems in formative measurement—interpretational confounding and interpretational ambiguity—and propose a novel resolution. Interpretational confounding occurs when using the traditional free-estimation approach, because the weights of different formative indicators vary as the dependent variable changes, resulting in the distortion of the measurement weights of the focal formative construct and thus jeopardizing the generalizability of empirical tests. Another way to alleviate the interpretational-confounding issue is to include the multiple indicators multiple causes (MIMIC) construct in the path model (i.e., MIMIC-path). Unfortunately, this method has led to the second major problem of interpretational ambiguity, the existence of more than one potential explanation of the formative model. More specifically, reflective indicators in the MIMIC model can be viewed as (1) indicators of the MIMIC construct, (2) dependent variables of the formative construct, or (3) indicators of a reflective construct affected by independent variables (formative indicators). To resolve these issues, we propose a two-stage fixed-weight redundancy model (FWRM) approach. We demonstrate the applicability of the FWRM approach with a set of survey data. We conducted a simulation study evaluating the FWRM approach by comparing it with the commonly used free-estimation and MIMIC-path methods. The results indicate that our FWRM approach can indeed improve the validity of formative construct modeling by mitigating confounding and ambiguity issues

    Exploring Individuals’ Loyalty To Online Support Groups From the Perspective Of Social Support

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    Prior research indicates that social support allows individuals to have additional skills to handle stresses, enhance self-esteem, and increase psychological well-being. Online social networks have become an emerging and important source of social support. However, little research has been done to explore how IT usage may improve the well-being and life quality of individuals, especially patients. Little research has been done to empirically examine individuals’ loyalty toward online social groups from the perspective of social support. This study aims to develop an integrated research model to the impact of online social support on psychological well-being and group identification, and individuals’ subsequent loyalty toward online social groups. Online social support group was operationalized as a second-order construct with four components: informational, emotional, esteem, and network supports. Data collected from 537 users of online support groups for mothers in Taiwan provide strong support for the research model. The results indicate that online social support is positively associated with psychological well-being and group identification, which in turn have a positive effect on moms’ loyalty toward online social groups. Implications for theory and practice and suggestions for future research are provided

    Land Subsidence Caused by Groundwater Exploitation in Yunlin, Taiwan

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    Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive

    Understanding the Impact of Service Failure and Recovery Justice on Consumers’ Satisfaction and Repurchase Intention

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    This research attempts to explore the impacts of different types of justice and their interactions on the satisfaction toward service failure recovery. We attempt to classify justices into hygiene, motivator, or asymmetric variable, based on the concept of asymmetric effect and two factors theory proposed by Herzberg. Specifically, we predict that procedural and distributive justices are hygiene or performance factor and interpersonal justice is motivator. In addition, based on expectancy-disconfirmation theory (EDT), we also attempt to understand the interaction between paired justices by arguing that motivator can generate more effect when hygiene factor or performance factors meet initial expectation. An experiment, with 3x2x2 between-subjects factorial design consisting of three factors to represent different levels of justice provided by online retailer, will be conducted to test the proposed hypotheses. A two-step approach will be used to (1) confirmation the types (hygiene, performance, or motivator) that each justice dimension belongs to, (2) understand the impact of each justice on satisfaction, and (3) test whether motivator will generate more effect when hygiene and performance factor are satisfied

    The squeeze film effect on micro-electromechanical resonators

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    The air squeeze film damping effect on the dynamic responses of clamped micro- electromechanical resonators is investigated in this study. A dynamic model for a clamped micro-electromechanical resonator with the damping consideration is derived using Lagrange’s equation. The corresponding resonator eigen solutions are formulated and solved by employing the assumed-mode method. The effect of different parameters; i.e. the resonator size, ambient temperature and pressure on the squeeze film damping characteristics were simulated and investigated. The results indicate that the squeeze film damping effect may significantly affect the dynamic responses of micro-scale electromechanical resonator

    Genetic and Functional Analysis of the DLG4 Gene Encoding the Post-Synaptic Density Protein 95 in Schizophrenia

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    Hypofunction of N-methyl-D-aspartate (NMDA) receptor-mediated signal transduction has been implicated in the pathophysiology of schizophrenia. Post-synaptic density protein 95 (PSD95) plays a critical role in regulating the trafficking and activity of the NMDA receptor and altered expression of the PSD95 has been detected in the post-mortem brain of patients with schizophrenia. The study aimed to examine whether the DLG4 gene that encodes the PSD95 may confer genetic susceptibility to schizophrenia. We re-sequenced the core promoter, all the exons, and 3′ untranslated regions (UTR) of the DLG4 gene in 588 Taiwanese schizophrenic patients and conducted an association study with 539 non-psychotic subjects. We did not detect any rare mutations at the protein-coding sequences of the DLG4 gene associated with schizophrenia. Nevertheless, we identified four polymorphic markers at the core promoter and 5′ UTR and one single nucleotide polymorphism (SNP) at the 3′UTR of the DLG4 gene in this sample. Genetic analysis showed an association of a haplotype (C–D) derived from 2 polymorphic markers at the core promoter (odds ratio = 1.26, 95% confidence interval = 1.06–1.51, p = 0.01), and a borderline association of the T allele of the rs13331 at 3′UTR with schizophrenia (odds ratio = 1.19, 95% confidence interval = 0.99–1.43, p = 0.06). Further reporter gene assay showed that the C-D-C-C and the T allele of the rs13331 had significant lower activity than their counter parts. Our data indicate that the expression of the DLG4 gene is subject to regulation by the polymorphic markers at the core promoter region, 5′ and 3′UTR of the gene, and is associated with the susceptibility of schizophrenia

    Two-Dimensional Fracture Mechanics Analysis Using a Single-Domain Boundary Element Method

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    This work calculates the stress intensity factors (SIFs) at the crack tips, predicts the crack initiation angles, and simulates the crack propagation path in the two-dimensional cracked anisotropic materials using the single-domain boundary element method (BEM) combined with maximum circumferential stress criterion. The BEM formulation, based on the relative displacements of the crack tip, is used to determine the mixed-mode SIFs and simulate the crack propagation behavior. Numerical examples of the application of the formulation for different crack inclination angles, crack lengths, degree of material anisotropy, and crack types are presented. Furthermore, the propagation path in Cracked Straight Through Brazilian Disc (CSTBD) specimen is numerically predicted and the results of numerical and experimental data compared with the actual laboratory observations. Good agreement is found between the two approaches. The proposed BEM formulation is therefore suitable to simulate the process of crack propagation. Additionally, the anisotropic rock slope failure initiated by the tensile crack can also be analyzed by the proposed crack propagation simulation technique

    Audio-video Synchronization with Arbitrary, Non-periodic Video Sources

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    The latency between audio and video streams of a device is usually measured using stock test videos. Although the use of stock test videos eases analysis, the test video differs materially from real-world videos, which tend to be far more diverse in content and encoding schemes, resulting in laborious experimental setup and inaccurate synchronization. This disclosure describes techniques to measure the latency between the audio and video streams of a given device using arbitrary, real-world, audio-visual footage (test video). Characteristic video and audio frames and their differences in timestamps (characteristic durations) are identified within the test video. The test video is played by the device-under-test while being recorded by a high-precision video camera. Characteristic durations of the recorded footage are determined. The differences in characteristic durations between the test and the recorded videos are statistically analyzed to determine the AV asynchrony of the device-under-test

    Numerical modeling of unsaturated layered soil for rainfall-induced shallow landslides

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    In this paper, a pioneer study on numerical modeling of rainfall-induced shallow landslides in unsaturated layered soil using the variably saturated flow equation is presented. To model the shallow landslides, the infinite slope stability analysis coupled with the hydrological model with the consideration of the fluctuation of time-dependent pore water pressure and Gardner equation for soil water characteristic curve was developed. A linearization process for the nonlinear Richards equation to deal with groundwater flow in unsaturated layered soil is derived using the Gardner model. To solve one-dimensional flow in the unsaturated zone of layered soil profiles, flux conservation and the continuity of pressure potential at the interface between two consecutive layers are considered in the numerical discretization of the finite difference method. The validity of the proposed model is established in three numerical problems by comparing the results with the analytical and other numerical solutions. Application examples have also been conducted. Obtained results demonstrate that the fluctuation of pore water pressure in unsaturated layered soil dominates slope stability of landslides and the lowest factor of safety may occur at the interface between two consecutive layers. The findings observed in this study are a fundamental contribution to environmental protection engineering for landslides in areas with higher occurrence and vulnerability to extreme precipitation
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