Quality Leads (quality + lead)

Distribution by Scientific Domains

Selected Abstracts

Knowledge-sharing reward dynamics in knowledge management systems: Game theory,based empirical validation

Xi Zhang
Abstract There are several knowledge-sharing problems in knowledge-management system (KMS) contexts. Many organizations use rewards to motivate people to contribute knowledge, but there has been no conclusive evidence of the role of reward. We designed two game-theory models to explain why and how the different knowledge-sharing problems occur in a KMS and the effectiveness of rewards. We found that there are four types of Nash equilibriums in different knowledge-sharing situations (Perfect, Free-riding, Non-use, and Dormant). Complex situations also occur (e.g., the absence of consideration for knowledge quality leads to vicious cycles). People contribute low-quality knowledge that is not used, and thus the KMS spirals toward disuse. To provide proposition evidence, a case study in an enterprise resource planning vendor was conducted. Based on comparison with empirical evidence, proposition validity was ensured. To effectively facilitate knowledge sharing, our suggestion is that organizations not only add rewards but also apply some additional mechanisms, such as a quality-evaluating system, extended information technology support, and organizational policy. 2010 Wiley Periodicals, Inc. [source]

Poor host plant quality causes omnivore to consume predator eggs

Arne Janssen
Summary 1Omnivorous arthropods are known to change their diet when host plant quality is low. Consequently, it has been suggested that decreased plant quality has a twofold negative effect on herbivore populations: (1) a decrease in growth rate of herbivores; (2) omnivores include more herbivores in their diet. We hypothesized that decreased host plant quality may also cause omnivores to feed on predators, including their own enemies. 2We tested this hypothesis, using the omnivorous western flower thrips. This species is known to feed on many plant species, but also on the eggs of another herbivore, the two-spotted spider mite. Previous research has shown that a decrease in plant quality leads to increased feeding on spider mite eggs by western flower thrips. Western flower thrips also kill the eggs of various predatory mites, including those of the specialist predator of spider mites and those of a predatory mite that attacks western flower thrips itself. 3In this paper we investigate whether thrips larvae kill predator eggs to feed on them and whether this predation depends on host plant quality. 4Larval survival as well as developmental rate increased when plant tissue of low quality (sweet pepper) was supplemented with eggs of two predatory mite species or when it was supplemented with pollen, a high-quality food type. 5Supplementing high quality leaf tissue (cucumber) with predator eggs did not lead to increased survival and developmental rate. Thrips larvae fed significantly less on predatory mite eggs when pollen was available. 6Thus, thrips larvae indeed feed on predator eggs, including those of their predator, and they feed more on predator eggs when host plants are of low quality. [source]

Strategic Quality Decisions under Heterogeneous Resource Endowments

Byong-Duk Rhee
The literature on product competition advocates a differentiation strategy assuming firm homogeneity in resources. However, firm heterogeneity in resource endowments has long been recognized in economics. Merging these two perspectives, we show that the increase in consumer preference for quality leads to firms' aggressive price competition instead of quality differentiation. As consumers look for higher quality, the cost advantage arising from superior resources increases and makes head-to-head competition more profitable than accommodating a less efficient rival. When consumers are highly concerned about quality, even a small resource difference leads a more efficient firm to initiate cutthroat price competition for market dominance. [source]

Influence of bone density on the cement fixation of femoral hip resurfacing components

Rudi G. Bitsch
Abstract In clinical outcome studies, small component sizes, female gender, femoral shape, focal bone defects, bad bone quality, and biomechanics have been associated with failures of resurfacing arthroplasties. We used a well-established experimental setup and human bone specimens to analyze the effects of bone density on cement fixation of femoral hip resurfacing components. Thirty-one fresh frozen femora were prepared for resurfacing using the original instruments. ASR resurfacing prostheses were implanted after dual-energy X-ray densitometer scans. Real-time measurements of pressure and temperature during implantation, analyses of cement penetration, and measurements of micro motions under torque application were performed. The associations of bone density and measurement data were examined calculating regression lines and multiple correlation coefficients; acceptability was tested with ANOVA. We found significant relations between bone density and micro motion, cement penetration, cement mantle thickness, cement pressure, and interface temperature. Mean bone density of the femora was 0.82,,0.13,g/cm2, t- score was ,0.7,,1.0, and mean micro motion between bone and femoral resurfacing component was 17.5,,9.1,m/Nm. The regression line between bone density and micro motion was equal to ,56.7,, bone density,+,63.8, R,=,0.815 (p,<,0.001). Bone density scans are most helpful for patient selection in hip resurfacing, and a better bone quality leads to higher initial component stability. A sophisticated cementing technique is recommended to avoid vigorous impaction and incomplete seating, since increasing bone density also results in higher cement pressures, lower cement penetration, lower interface temperatures, and thicker cement mantles. 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:986,991, 2010 [source]