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161.
Information Exchange in Virtual Communities: A Comparative Study   总被引:1,自引:0,他引:1  
As more and more consumers spend more money on the Internet, traditional retailers and manufacturers as well as entrepreneurial dot-coms are jousting to explore and shape this new business opportunity. Their long-term survival and profitability may be determined by how well the Web site helps form and sustain positive attitudes toward the site and, eventually, toward the product or the company. The purpose of this study is two-fold: (1) to examine if and how attitude toward the Web site (Ast) affects consumer brand choice; and (2) to examine the association between Ast and consumers' confidence in choice, and the moderating effect of consumer product knowledge in its relationship. The study asked participants to choose a laptop brand after visiting three laptop manufacturer Web sites for a total of 30 minutes. Their product knowledge and attitude toward the three Web sites were also measured. The study found that attitude toward the Web site is a good predictor of consumer brand choice. In addition, confidence in choice seemed to be affected by Ast, depending on product knowledge. For a group with low product knowledge (novices), Ast was likely to influence confidence in choice. For a group with high product knowledge (experts), however, Ast did not seem to affect confidence in choice.  相似文献   
162.
Fabrication process of open surfaces by robotic fibre placement   总被引:3,自引:2,他引:3  
Composite materials are being used extensively in many industrial sectors. They offer excellent material properties compared to other structural materials available. However, the traditional fabrication process using manual hand lay-up is time consuming and labour intensive. Therefore, robotic fibre placement has been introduced to overcome these drawbacks. This approach may greatly reduce cycle time and manufacturing costs. This paper describes the overall strategy for the establishment of a flexible robotic fibre placement technique. The fabrication process planning of this new technique is presented. Three different types of fibre placement for open surfaces are discussed. These include simulation-based fibre path generation, fibre steering, and sensory-based contour following methodologies. The system architecture for the process control is also presented.  相似文献   
163.
Meta-analysis was used to aggregate results from studies examining the relationship between intelligence and leadership. One hundred fifty-one independent samples in 96 sources met the criteria for inclusion in the meta-analysis. Results indicated that the corrected correlation between intelligence and leadership is .21 (uncorrected for range restriction) and .27 (corrected for range restriction). Perceptual measures of intelligence showed stronger correlations with leadership than did paper-and-pencil measures of intelligence. Intelligence correlated equally well with objective and perceptual measures of leadership. Additionally, the leader's stress level and the leader's directiveness moderated the intelligence-leadership relationship. Overall, results suggest that the relationship between intelligence and leadership is considerably lower than previously thought. The results also provide meta-analytic support for both implicit leadership theory and cognitive resource theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
164.
Data are reported from 3,213 research eyewitnesses confirming that accurate eyewitness identifications from lineups are made faster than are inaccurate identifications. However, consistent with predictions from the recognition and search literatures, the authors did not find support for the "10-12-s rule" in which lineup identifications faster than 10-12 s maximally discriminate between accurate and inaccurate identifications (D. Dunning & S. Perretta, 2002). Instead, the time frame that proved most discriminating was highly variable across experiments, ranging from 5 s to 29 s, and the maximally discriminating time was often unimpressive in its ability to sort accurate from inaccurate identifications. The authors suggest several factors that are likely to moderate the 10-12-s rule. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
165.
In studies of episodic recognition memory, low-frequency words (LF) have higher hit rates (HR) and lower false alarm rates (FAR) than do high-frequency words (HF), which is known as the mirror pattern. A few findings have suggested that requiring a task at study may reduce or eliminate the LF-HR advantage without altering the LF-FAR effect. Other studies have suggested that the size of the LF-HR advantage interacts with study time. To explore such findings more thoroughly and relate them to theory, the authors conducted 5 experiments, varying study time and study task. The full mirror pattern was found only in 2 cases: the standard condition requiring study for a later memory test and a condition requiring a judgment about unusual letters. The authors explain their findings in terms of the encoding of distinctive features and discuss the implications for current theories of recognition memory and the word frequency effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
166.
Confocal scanning laser microscopy (CSLM) represents an exciting new tool for scientific disciplines which focus on mechanistic studies such as experimental pathology. Enhanced resolution in the specimen plane and rejection of out-of-focus fluorescence flare allow analysis of specific nucleic acid sequences, enzymes, structural macromolecules, and cellular homeostasis utilizing fluorescent probes. Four different experimental applications are discussed which utilize CSLM to evaluate pathological processes at the subcellular, cellular, and tissue levels. Programmed cell death, or apoptosis, is a natural process of significance both during development and as a response to toxic stimuli. CSLM-imaging of nuclei of human B lymphoblastoid cells following exposure to a monofunctional alkylating agent suggests that the degradation of chromatin characteristic of apoptosis may occur in asymmetric patterns. Surfactant apoprotein-A is the major non-serum protein component of pulmonary surfactant and is essential for the extracellular function of surfactant. CSLM of alveolar type II cells suggests that apoprotein-A is present in both the cytoplasm, predominantly in lamellar bodies, and in the nucleus. The tumor promoter, phorbol myristate acetate, rapidly stimulated the formation of vacuoles in human neutrophils. CSLM using Lucifer Yellow as a probe suggests that cylindrical vacuoles are formed by fluid-phase pinocytosis. The blood-nerve barrier (BNB) in peripheral nerves may be an important target during toxin-induced neuropathies. Ricin-induced permeability of the BNB in the rat was rapidly visualized by CSLM as leakage of fluorescein isothiocynate (FITC)-dextran into the endoneurial compartment.  相似文献   
167.
A building on fire is a smoky and dark environment both for firefighters and for civilians trapped inside. The faster firefighters find a way to search for and rescue civilians at a fire scene, the higher the survival rate of those trapped inside. This study presents a discussion on the characteristics of firefighter wayfinding under low visibility. The firefighters who participated in this study underwent testing at a training ground. The participants’ search and wayfinding paths were recorded using radiofrequency identification (RFID) technology. The results revealed that the mean searching time in each room decreased from 135 to 19 s as the firefighters became increasingly familiarized with the task. As expected, data also shows that smaller rooms contributed to shorter searching times. Most participants could manage a maximum of three rooms, with wayfinding confusion manifested after they had searched through the third room. These findings are crucial for the design of fireground strategies and training.  相似文献   
168.
Social networking site (SNS) use decisions have led to major economic and social transformations worldwide. While many organizations seek to use SNSs from a strategic perspective to reach their customer, it is important to understand what makes SNSs successful in order to use them for competitive purposes. The current research evaluates the influence of the social capital theory on SNS success measures. A model was developed and empirically tested using two data samples to ensure valid and reliable results for success of SNSs. The results display the importance of social capital in SNS success followed by practitioner and academic implications.  相似文献   
169.
Problem, research strategy, and findings: Local governments across the United States have for decades relied on the autocentric level of service (LOS) metric to analyze and impose exactions for the transportation impacts of land use developments. In California, LOS has dominated transportation impact analysis under the state’s project-level environmental review law. In that role, LOS has exacerbated the state’s notoriously tortuous development approval processes, particularly in urban areas. But LOS is on its way out. The state recently replaced LOS with vehicle miles traveled (VMT) as the primary measure—and basis for mitigation—of transportation impacts under the California Environmental Quality Act. Local governments must make the switch by July 1, 2020. We use a historical counterfactual approach to assess how replacing LOS with VMT could have affected the approval process for 153 land development projects over 16?years in the city of Los Angeles. We find that most projects could have benefited from at least some environmental review streamlining under the VMT-based framework recommended by the state, including more than 75% of residential-containing projects.

Takeaway for practice: Our results suggest that swapping LOS for VMT could reduce the environmental review burden for development in low-VMT urban areas and provide at least some of the approval process streamlining necessary to increase housing production in California. Similar impacts from an LOS-to-VMT switch could also potentially accrue outside of California under the right conditions, but more research is needed.  相似文献   

170.
Gary Cokins 《EDPACS》2013,47(6):11-21
Abstract

Enterprise performance management (EPM) is the integration of control and improvement methods imbedded with analytics. Its methods include the strategy map, balanced scorecards, costing (including activity based cost management), budgeting, forecasting and resource capacity requirements planning. These methods fuel other core solutions such as customer relationship management (CRM), supply chain management (SCM), risk management, and human capital management systems, as well as lean management and Six Sigma initiatives.  相似文献   
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