Chatter Suppression with Ultrasonic Elliptical Vibration Based on Energy Principle

A new method is proposed to suppress chatter, in which the ultrasonic elliptical vibration is added on the cutting tool edge. It results in the fact that the rake face of tool is separated from the chip and the direction of the frictional force between the rake face and the chip is reversed in each cycle of elliptical vibration cutting. The experimental investigations show that the chatter can be suppressed effectively by adding ultrasonic elliptical vibration on the cutting tool edge. In order to make clear the reason of chatter suppression, the mechanism of chatter suppression is analyzed theoretically from the viewpoint of energy.     

The Influence of Cue Type on Backward Inhibition.

Backward inhibition is proposed as a process of lateral inhibition that operates during response selection in task switching, reducing interference caused by the most recently abandoned task set. The effect has been observed across a wide range of contexts but is eliminated by using spatial location to cue tasks (K. D. Arbuthnott & T. S. Woodward, 2002). The present studies replicated this finding, showing that spatial cues are also associated with greater response congruity than verbal cues, consistent with the lateral inhibition model. Spatial cues may introduce greater discriminability between competing category-response rules, reducing the need for lateral inhibition. However, when participants named the task before target presentation, backward inhibition was observed with spatial cues, suggesting that verbalization increased competition between sets, despite spatial localization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Suppression of burrs in turning with ultrasonic elliptical vibration cutting

The approximate cutting force models in three-dimensional separating type ultrasonic elliptical vibration cutting are proposed in present paper. The theoretical models of the stresses of deformation zone on the workpiece edge in burr formation in ultrasonic elliptical vibration cutting are derived based on three-dimensional cutting model, and the reason for the burr being suppressed by applying ultrasonic elliptical vibration is clarified theoretically. Finally, the effect of ultrasonic elliptical vibration cutting on the burr is verified experimentally.     

Suicide Attempt Self-Injury Interview (SASII): Development, reliability, and validity of a scale to assess suicide attempts and intentional self-injury.

The authors describe the development of the Suicide Attempt Self-Injury Interview (SASII), an instrument designed to assess the factors involved in nonfatal suicide attempts and intentional self-injury. Using 4 cohorts of participants, authors generated SASII items and evaluated them with factor and content analyses and internal consistency statistics. The final measure was assessed for reliability and validity with collateral measures. The SASII assesses variables related to method, lethality and impulsivity of the act, likelihood of rescue, suicide intent or ambivalence and other motivations, consequences, and habitual self-injury. The SASII was found to have very good interrater reliability and adequate validity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contingency Planning in LAN/WAN Environments

When a disaster recovery plan (DRP) is in place in a company, it is often solely for the mainframe; too often no attention is paid to the departmental distributed servers.     

How virtual are we? Measuring virtuality and understanding its impact in a global organization

Abstract.  Employees in global corporations are increasingly involved in 'virtual teams' on a regular basis. Conflicting definitions of virtuality make it hard to measure such things as how much virtual teaming occurs and how virtual teaming affects performance. As a consequence, it is hard to allocate funding and to design infrastructures and software to support this specific mode of working. Using the concept of discontinuities, or changes in expected conditions, we propose a virtuality index to assess how 'virtual' a given setting is. The discontinuities used include geography, time zone, organization, national culture, work practices, and technology. The index separately measures these aspects of virtuality and their effect on perceived team performance. Data collected at a large multinational corporation clustered into three overarching discontinuities: team distribution, workplace mobility, and variety of work practices. The study revealed that being distributed in and of itself had no impact on self-assessed team performance. Work practice predictability and sociability mitigated effects of working in discontinuous environments, while variety of practices (cultural and work process diversity) and employee mobility negatively impacted performance.     

Evaluation of the Interaction between Phosphohistidine Analogues and Phosphotyrosine Binding Domains

We have investigated the interaction of peptides containing phosphohistidine analogues and their homologues with the prototypical phosphotyrosine binding SH2 domain from the eukaryotic cell signalling protein Grb2 by using a combination of isothermal titration calorimetry and a fluorescence anisotropy competition assay. These investigations demonstrated that the triazole class of phosphohistidine analogues are capable of binding too, suggesting that phosphohistidine could potentially be detected by this class of proteins in vivo.     

Impact of road safety interventions on traffic-related occupational injuries in Spain, 2004–2010

Objectives

To evaluate the impact of road safety interventions, including the penalty point system (PPS) and the reformed Spanish penal code (RPC), on traffic-related occupational injuries in Spain.

Methods

The study design was an interrupted time-series with a comparison group. The study group had traffic-related, occupational injuries incurred during working and commuting hours; the comparison group had non-traffic-related injuries incurred at the work site. A negative binomial regression model was used to determine the relative risk (RR) of sustaining occupational injuries for the post-intervention periods compared to the non-intervention period.

Results

Non-fatal, traffic-related injuries did not significantly change after the PPS and RPC implementations, except for those occurred in commuting hours, which increased significantly after the PPS. On the other hand, after the RPC, fatal, traffic-related injuries decreased significantly during working hours (0.79; 95%CI 0.65 to 0.97) and commuting hours (RR: 0.63; 95%CI:0.56 to 0.72), although fatal, non-traffic-related injuries also decreased at the work site.

Conclusions

Road safety interventions did not clearly affect traffic-related occupational injuries in Spain. Specific occupational risk factors could influence the occurrence of those injuries.     

Latent risk and trend models for the evolution of annual fatality numbers in 30 European countries

In this paper a unified methodology is presented for the modelling of the evolution of road safety in 30 European countries. For each country, annual data of the best available exposure indicator and of the number of fatalities were simultaneously analysed with the bivariate latent risk time series model. This model is based on the assumption that the amount of exposure and the number of fatalities are intrinsically related. It captures the dynamic evolution in the fatalities as the product of the dynamic evolution in two latent trends: the trend in the fatality risk and the trend in the exposure to that risk. Before applying the latent risk model to the different countries it was first investigated and tested whether the exposure indicator at hand and the fatalities in each country were in fact related at all. If they were, the latent risk model was applied to that country; if not, a univariate local linear trend model was applied to the fatalities series only, unless the latent risk time series model was found to yield better forecasts than the univariate local linear trend model. In either case, the temporal structure of the unobserved components of the optimal model was established, and structural breaks in the trends related to external events were identified and captured by adding intervention variables to the appropriate components of the model. As a final step, for each country the optimally modelled developments were projected into the future, thus yielding forecasts for the number of fatalities up to and including 2020.     

Evaluation of a child passenger safety class in increasing parental knowledge

Background

Child passenger restraint systems have been found to greatly reduce the risk of injury and death among child passengers. However, nearly half of the children who died in 2009 as a result of motor vehicle crashes were completely unrestrained. Our global hypothesis is that parents and other caregivers failed to restrain children due to a lack of child passenger seat education and practice. In this report, we postulate that a car seat class will improve the basic understanding of child passenger safety. The objective of the study was to evaluate the effectiveness of a car seat class in increasing parental knowledge about child passenger safety.

Methods

Car seat classes were held at a Level 1 pediatric trauma center every other Tuesday for ten months. The curriculum consisted of: child passenger safety laws discussion, a 21-min video on the use of child safety seats followed by a 15-min discussion about the video, 15 min of discussing the different types of car seats, and hands-on training on how to properly install and use child restraints. Free car seats were provided to eligible parents. The pre-test was administered at the beginning of class and the post-test at the end of the class. McNemar's test and a paired t-test were used to compare pre- and post-test scores. Test scores were also stratified by language spoken.

Results

Forty-four classes were held and a total of 491 parents/caregivers attended the classes. An increase in knowledge was found for all survey questions. Mean knowledge score for the post-test was 3.10 points higher compared to the mean knowledge score from the pre-test. Mean difference in knowledge scores for English-speaking participants were higher than Spanish-speaking participants.

Conclusion

Lack of knowledge and low risk perception have frequently been cited as barriers for the use of child passenger restraints. Our intervention attempted to eliminate these barriers. We found that this intervention was effective at increasing parental knowledge about child passenger safety. The results of this study may be used to design and implement future interventions in multicultural settings.