41 research outputs found
Annoyance of helicopter impulsive noise
Psychoacoustic studies of helicopter impulsive noise were conducted in order to qualify additional annoyance due to this feature and to develop physical impulsiveness descriptors to develop impulsivity correction methods. The currently proposed descriptors and methods of impulsiveness correction are compared using a multilinear regression analysis technique. It is shown that the presently recommended descriptor and correction method provides the best correlation with the subjective evaluations of real helicopter impulsive noises. The equipment necessary for data processing in order to apply the correction method is discussed
Helicopter internal noise reduction research and development application to the SA 360 and SA 365 Dauphin
Noise sources inside helicopter cabins are considered with emphasis on the mechanisms of vibration generation inside the main gear box and mechanisms of transmission between source and cabin. The dynamic behavior of the main gear box components is examined in relation to the transfer of vibration energy to the structure. It is indicated that although improvements can be made in noise reduction at the source, a soundproofing treatment isolating the passenger from the noise source is necessary. Soundproofing treatments installed and optimized include: (1) an acoustic screen using the weight effect to isolate the passenger from the noise source; (2) a damping treatment to limit the conversion of the vibratory energy into acoustic energy; and (3) an absorbing treatment achieved either through HELMHOLTZ resonators or through a glass wool blanket to limit the propagation of acoustic waves and the wave reflection effects in the cabin. The application of treatments at the source and the optimization of the sound barriers improved the noise level by about 30 db
A taxonomical framework of socio-cultural hazards in transport hubs
This article presents a taxonomical framework that supports the considerations of socio-cultural hazards that may affect crowd management in transport hubs, i.e. airports, ports, underground and train stations, both in normal and emergency situations. Such hazards include communication breakdowns with passengers due, for instance, to language barriers; increased potential for revolts, as in stranded passenger situations; misreporting of security threats; and uncooperative behaviour in case of emergencies. Such socio-cultural hazards are not normally considered from the integrated perspective of transport hub operators, e.g. security staff, first responders and service assistants as well as safety and security managers. The present study provides an integrated perspective of these hazards as a means to increase the performance of transport staff members that interact with the public and with passengers on a daily basis. The methodology used to develop the framework comprises: (i) a focus group with relevant experts, (ii) semi-structured interviews at operational facilities with front-end practitioners, and (iii) a review of academic literature and media reports. The framework has also been qualitatively corroborated with transport operators in dedicated interviews and a focus group session. The study identified 10 socio-cultural hazards that were combined into a single framework comprising three high-level sub-categories: (i) crowd–staff interactions, (ii) crowd–crowd interactions, and (iii) crowd–environment interactions. The framework of socio-cultural factors can increase staff’s awareness of relevant socio-cultural hazards, their potential consequences in both normal and emergency situations, and the associated mitigation strategies. In turn, this can increase the quality and continuity of service, safety and security in the management of members of the public and passengers in transport hubs
Adherence issues related to sublingual immunotherapy as perceived by allergists
Objectives: Sublingual immunotherapy (SLIT) is a viable alternative to subcutaneous immunotherapy to treat allergic rhinitis and asthma, and is widely used in clinical practice in many European countries. The clinical efficacy of SLIT has been established in a number of clinical trials and meta-analyses. However, because SLIT is self-administered by patients without medical supervision, the degree of patient adherence with treatment is still a concern. The objective of this study was to evaluate the perception by allergists of issues related to SLIT adherence. Methods: We performed a questionnaire-based survey of 296 Italian allergists, based on the adherence issues known from previous studies. The perception of importance of each item was assessed by a VAS scale ranging from 0 to 10. Results: Patient perception of clinical efficacy was considered the most important factor (ranked 1 by 54% of allergists), followed by the possibility of reimbursement (ranked 1 by 34%), and by the absence of side effects (ranked 1 by 21%). Patient education, regular follow-up, and ease of use of SLIT were ranked first by less than 20% of allergists. Conclusion: These findings indicate that clinical efficacy, cost, and side effects are perceived as the major issues influencing patient adherence to SLIT, and that further improvement of adherence is likely to be achieved by improving the patient information provided by prescribers. © 2010 Scurati et al, publisher and licensee Dove Medical Press Ltd
Analisi non simmetrica delle corrispondenze e modelli decisionali di scelta modale: un approccio statistico integrato
Modello di misurazione dei Critical Success Factors in una implementazione di un sistema E.R.P.
KNOWLEDGE-BASED CONTROL IN MULTISENSOR IMAGE-PROCESSING AND RECOGNITION
An approach to the control of multisensor image processing and recognition based on a suitable representation of control knowledge in symbolic form is presented. A hierarchical organization of control knowledge, corresponding to a decomposition of the image recognition process into subprocesses, is proposed. The knowledge for the control of the low-level and high-level phases is described in detail. The control problem involved in the automatic selection and tuning of image processing algorithms is addressed using data structures representing advised sequences of algorithms, a symbolic representation of quality control, and control strategies with backtracking capabilities. Error handling in the high-level phase is faced by a functional decomposition of the error-handling task into error states and types and by a hierarchical representation of the control knowledge for error detection and recovery. Results obtained in a real-world multisensor application are reported, and the improvement in classification accuracy obtained by the proposed error-handling mechanisms is evaluated
KNOWLEDGE-BASED CONTROL IN MULTISENSOR IMAGE-PROCESSING AND RECOGNITION
An approach to the control of multisensor image processing and recognition based on a suitable representation of control knowledge in symbolic form is presented. A hierarchical organization of control knowledge, corresponding to a decomposition of the image recognition process into subprocesses, is proposed. The knowledge for the control of the low-level and high-level phases is described in detail. The control problem involved in the automatic selection and tuning of image processing algorithms is addressed using data structures representing advised sequences of algorithms, a symbolic representation of quality control, and control strategies with backtracking capabilities. Error handling in the high-level phase is faced by a functional decomposition of the error-handling task into error states and types and by a hierarchical representation of the control knowledge for error detection and recovery. Results obtained in a real-world multisensor application are reported, and the improvement in classification accuracy obtained by the proposed error-handling mechanisms is evaluated