Unfolding simple chains inside circles

It is an open problem to determined whether a polygonal chain can be straightened inside a confi ning region if its links are not allowed to cross. In this paper we propose a special case: whether a polygonal chain can be straightened inside a circle without allowing its links to cross. We prove that this is possible if the straightened confi guration can fi t within circle. Then we show that these simple chains have just one equivalence class of confi gurations

Detection of Helicobacter pylori using PCR in dental plaque of patients with and without gastritis

Objectives: Helicobacter pylori (H. pylori) accounts for gastritis, peptic ulcer and is a probable cause of gastric cancer. Since its detection in the oral cavity, concerns have been raised about dental plaque as a reservoir for reinfection. The aim of this study was to detect the organism in the dental plaque and to determine the association, if any, between H. pylori gastritis and dental plaque contamination causing H. pylori. Study design: A polymerase chain reaction-based method was used for detection of H. pylori in clinical specimens. Supra and subgingival samples were collected from 67 patients with chronic periodontitis, 23 of whom were also suffering from gastritis. The data were analyzed with Chi square and Fisher exact test and the statistical significance was set to 0.05. Results: H. pylori was scarce in patients with periodontitis(5.9%). There was a significant association between the presence of H. pylori in the dental plaque and gastritis (p=0.012). Conclusions: Although rarely seen, H. pylori infected dental plaque may be a source for reinfection. It is therefore suggested that professional plaque removal and oral hygiene procedures be performed, along with the antibiotic treatment of H. pylori

The Structural Model of Social Well-being in workplace based on Bright-side Personality, Dark Triad and Collectivism Culture,Considering the Mediating Role of Social Influence

Introduction: Social well-being is one of three employee well-being dimensions and the missed piece of subjective well-being literature. The purpose of current research was modeling the social well-being in workplace, based on person-situation model and social exchange theory. This mediated-moderated structural model is developed considering the interactive role of bright and dark triad and collectivism organizational culture, besides mediation role of social influence tactics.Method: Partial least squares structural equation modeling (PLS-SEM) was used for analyzing this second-order hierarchical latent variable model. Participants were 292 employees of Iran National oil Company in the summer of 1398.Results: Fitness indices indicates the good fitness of social-wellbeing model (SRMR<0.08, NFI>0.9). Results showed that bright side of personality and collectivism organizational culture affect social well-being directly. In addition, findings showed that dark triad influences on social well-being is fully mediated by social influence tactics; so that Machiavellianism and narcissism increase the social well-being levels by influencing soft influence tactics utilization; Whereas psychopathy leads to applying hard influence tactics and cause social well-being reduction. Moderating effect of collectivism organizational culture on bright side of personality and social well-being was confirmed as well.Conclusion: Overall findings indicate that personality factors are important determinants of social well-being, but understanding the social well-being construct in workplace requires including the whole image of bright and dark side of personality, as well as organization cultural factors

Computer Aided Design Tool for Electric, Hybrid Electric and Plug-in Hybrid Electric Vehicles

This research is focused on designing a new generation of CAD tools that could help a ”hybrid vehicle” designer with the design process to come up with better vehicle configurations. The conventional design process for any type of hybrid-electric vehicle would start from the vehicle performance criteria and continue by applying them to the physical models of different components of the vehicle. The final result would be strict and precise characteristics of all components in the vehicle; this scenario gives only one option for the desired vehicle. A new perspective is introduced in developing a new methodology in the art of design. This new method enables the designer to see a wider picture of what he is designing and have access to all his options and capabilities. The method is designed to help the designer ask the right questions about his design options, intelligently guide him through the design process by squeezing the space of solutions and take him to the final designed product. The new methodology is implemented in this research with the following capabilities: 1. The proposed tool allows the designer to choose any arbitrary set of variable to be known and leave the rest as the ones to be solved for; either they are vehicle component characteristic variables or performance measures. This provides a great amount of flexibility and success in designing a vehicle from any available information about it. 2. Instead of starting from single values, the new tool can work with a range of possible values for the known variables and suggest range of feasible values for the unknown variables. This provides the capability of refining the design even further and performing sensitivity analysis. 3. The proposed tool is a package that offers both design and simulation capabilities. It includes analytical performance simulation as well as simulation with arbitrary drive cycles and engine controllers. 4. Capability of 1D, 2D and 3D representation of any arbitrary set of design variables in the solution space. The idea is implemented in a pilot version software package for vehicle design

The Survey to Determine the Accuracy Rate of the Neoplasm Coding in Seyed Al-Shohada Hospital of Isfahan

Introduction: The use of cancer suffering patients' information is possible when this information was organized and categorized properly through encoding the diagnoses and therapeutic procedures. Therefore the aim of this study was to determine the accuracy rate of the neoplasm coding in Seyed Al-Shohada Hospital of Isfahan city in 2011. Method: This study was a descriptive and cross-sectional study. The population of this study were medical records created during the second half of 2011,308 ones of which were selected as sample. A self-designed checklist was the research tool, which was used after validation. Data analysis was performed using SPSS v16. Software through descriptive statistics. Results: Investigating the surveyed records, the researchers found that the accuracy rate of the records in this hospital was 68%. Also the highest accuracy rate of the coding has been associated with neoplasms of the connective tissue (94%). Conclusion: Regarding the obtained results, it is recommended that coding of morphology & related Z codes of neoplasms be set in coders' work order. It is also recommended that continuous educational coding courses be held in order to increase the accuracy rate of the neoplasm coding

More on -Normal Operators in Hilbert Spaces

We study some properties of (,)-normal operators and we present various inequalities between the operator norm and the numerical radius of (,)-normal operators on Banach algebra ℬ(ℋ) of all bounded linear operators ∶ℋ→ℋ, where ℋ is Hilbert space

Thermal error modelling of machine tools based on ANFIS with fuzzy c-means clustering using a thermal imaging camera

Thermal errors are often quoted as being the largest contributor to CNC machine tool errors, but they can be effectively reduced using error compensation. The performance of a thermal error compensation system depends on the accuracy and robustness of the thermal error model and the quality of the inputs to the model. The location of temperature measurement must provide a representative measurement of the change in temperature that will affect the machine structure. The number of sensors and their locations are not always intuitive and the time required to identify the optimal locations is often prohibitive, resulting in compromise and poor results. In this paper, a new intelligent compensation system for reducing thermal errors of machine tools using data obtained from a thermal imaging camera is introduced. Different groups of key temperature points were identified from thermal images using a novel schema based on a Grey model GM (0, N) and Fuzzy c-means (FCM) clustering method. An Adaptive Neuro-Fuzzy Inference System with Fuzzy c-means clustering (FCM-ANFIS) was employed to design the thermal prediction model. In order to optimise the approach, a parametric study was carried out by changing the number of inputs and number of membership functions to the FCM-ANFIS model, and comparing the relative robustness of the designs. According to the results, the FCM-ANFIS model with four inputs and six membership functions achieves the best performance in terms of the accuracy of its predictive ability. The residual value of the model is smaller than ± 2 μm, which represents a 95% reduction in the thermally-induced error on the machine. Finally, the proposed method is shown to compare favourably against an Artificial Neural Network (ANN) model