Antonio Forcina

Memory and anatomical change in severe non missile traumatic brain injury: ∼1 vs. ∼8 years follow-up

In previous studies, we investigated a group of subjects who had suffered from a severe non missile traumatic brain injury (nmTBI) without macroscopic focal lesions and we found brain atrophy involving the hippocampus, fornix, corpus callosum, optic chiasm, and optic radiations. Memory test scores correlated mainly with fornix volumes [37,38]. In the present study, we re-examined 11 of these nmTBI subjects approximately 8 yr later. High-spatial resolution T1 weighted magnetic resonance images of the brain (1mm(3)) and standardised memory tests were performed once more in order to compare brain morphology and memory performance originally assessed 3-13 months after head injury (first study) and after 8-10 yr (present study). An overall improvement of memory test performance was demonstrated in the latest assessment, indicating that cognitive recovery in severe nmTBI subjects had not been completed within 3-13 months post-injury. It is notable that the volumes of the fornix and the hippocampus were reduced significantly from normal controls, but these volumes do not differ appreciatively between nmTBI subjects at first (after ∼1 yr) and at second (after ∼8 yr) scans. On the contrary, a clear reduction in the volume of the corpus callosus can be observed after ∼1 yr and a further significant reduction is evident after ∼8 yr, indicating that the neural degeneration in severe nmTBI continues long after the head trauma and relates to specific structures and not to the overall brain.

A-IFM reliability allocation model based on multicriteria approach

Purpose – The purpose of this paper is to evaluate reliability allocation using an aerospace system prototype. The proposed approach has been applied and compared with other traditional methods on an aerospace system prototype, where the reliability allocation process is rigorous. Design/methodology/approach – The new approach is based on integrated factors method (IFM), whose values are adjusted trough a multicriteria method, the analytic hierarchy process, depending on the importance of each factor and each unit of the system. The result is a dynamic model, that combines the advantages of the allocation method and the multicriteria decision-making technique. Findings – The reasons that led to the development of the IFM-based AHP are the outcome of a careful analysis of the current military and commercial approaches. In particular most of analyzed methods use constant weights for the factors involved in the reliability allocation; different weights are rarely assigned to these factors. Research limitatio...

Validation and application of a reliability allocation technique (Advanced Integrated Factors Method) to an industrial system

The proposed work analyses and applies a new reliability and redundancy allocation procedure. Starting from a similar methodology previously developed by the authors, Integrated Factors Method (IFM), a new reliability allocation and optimization method is developed: Advanced Integrated Factors Method (AIFM). The new technique has been proposed to analyze complex systems in the pre-design phase, even if its general characteristics allow extending the method to different design and production phases. The previous method has been improved through the introduction of new indexes that help improve underperforming components in order to achieve the allocated reliability values. The method introduces a big number of factors, so it can be applied to a wide range of systems. It is characterized by a very simple mathematical formulation, that can be made more complicated for a more detailed analysis.

Life cycle assessment of recycled concretes: A case study in southern Italy

Concrete industry is responsible of the most significant contribution to the global warming due to the large amount of substances with environmental impacts produced during its entire life cycle (production process, construction, maintenance, dismantlement, and scrapping). The most important issue characterizing the concrete industry is related to the constant growth of consumption of natural aggregates. The purpose of the present research is to apply the standard protocol of life cycle assessment to 3 different concrete mixtures composed by wastes from construction and demolition (C&D), marble sludge and cement kiln dust (CDK) in order to compare the environmental and energy impacts. The main purpose is to analyze the potentials (capabilities/benefits) of recycled aggregate concrete. The proposed model analyses 37 recovery possible scenarios. The results were analyzed with the software SimaPro© and with the life cycle impact assessment method Eco Indicator 99. The results show how it is possible to decide for the optimal solution in order to reduce emissions and impacts due to the concrete production.

Inventory management using both quantitative and qualitative criteria in manufacturing system

Abstract The success parameters for any company are on time completion, within specific budget and with requisite performance. In particular an efficient and effective inventory management helps a firm maintaining competitive advantage, especially in a time of accelerating globalization. From this point of view several organizations employ the ABC analysis to have an efficient control on a large number of inventory items. With the increasing levels of integration in manufacturing and service systems conventional ABC analysis is limited because it accounts for only one criterion, mostly “annual dollar usage”, for classifying inventory items. To alleviate this shortcoming, this paper proposes a modified version of ABC analysis and Cross Analysis based on Analytic Network Process, a multicriteria approach, that allows to consider several criteria all at once for the optimal choice of materials management.

Study and modelling of very flexible lines through simulation

The present paper proposes the development of a virtual model simulating an assembly line. Starting from the analysis of the real line, through an incremental approach, a simulation model is created, verified and validated, in order to obtain useful information about: • productive capacity; • partial and total lead time; • Percentage of saturation, Value Added (VA) and Non-Value Added (NVA), for each worker and station. During the development phase, an important goal has been pursued: the possibility to use and change the model without knowing the creation logic. It is possible to change input parameters through simple tables, which contain times of man-machine operations. You can easily set times in order to move an operation from one station to another or to add/delete a job in a station, according to the technological and ergonomic constraints of the process. Moreover, the acquisition of scheduling data is extremely easy and starts from the generation of a list of production codes related to different work-cycles.

AHP-IFM Target: An Innovative Method to Define Reliability Target in an Aerospace Prototype Based on Analytic Hierarchy Process

Reliability target definition is a crucial aspect of any reliability analysis. In literature, there are two types of analysis. The first one, called ‘bottom-up’, goes back to the systems target using data of units through a fault tree analysis. Reliability data of components could be only partially available, particularly in the case of innovative systems. In the second type of analysis, called ‘top-down’, starting from similar systems, the target of each unit is defined, by applying allocation techniques. Also, in this case, reliability data of similar systems might not be available, and the choice of the most appropriate technique could be tricky. The purpose of the present research is to combine the advantages of both usual approaches. The newly developed approach is based on the integrated factors method, whose values are adjusted trough a multicriteria method, the analytic hierarchy process, depending on the importance of each factor and each unit. The innovation of the proposed model consists in its dynamism, as most of the literature methods use constant weights for the factors involved in reliability allocation. No method takes into account the assignment of a different level of significance (weight) to different units of the system, simultaneously with the considered factors. The developed approach has been applied on an aerospace prototype system. The results show the goodness of the new method and its ability to overcome the problems noted in literature. Copyright

Quality of life in persons after traumatic brain injury as self-perceived and as perceived by the caregivers

The primary aim of the study was to adopt QOLIBRI (quality of life after brain injury) questionnaire in a proxy version (Q-Pro), i.e., to use caregivers for comparison and to evaluate whether TBI patients’ judgment corresponds to that of their caregivers since the possible self-awareness deficit of the persons with TBI. A preliminary sample of 19 outpatients with TBI and their proxies was first evaluated with the Patient Competency Rating Scale to assess patients’ self-awareness; then they were evaluated with the QOLIBRI Patient version (Q-Pt) and a patient-centered version of the Q-Pro. Subsequently, 55 patients and their caregivers were evaluated using the patient-centered and the caregiver-centered Q-Pro versions. Q-Pt for assessing Quality of Life (QoL) after TBI, as patients’ subjective perspective and Q-Pro to assess the QoL of patients as perceived by the caregivers. The majority of patients (62.2%) showed better self-perception of QoL than their proxies; however, patients with low self-awareness were less satisfied than patients with adequate self-awareness. Low self-awareness does not impair the ability of patients with TBI to report on satisfaction with QoL as self-perceived.

Failure Prevention Through Performance Evaluation of Reliability Components in Working Condition

The reliability of a system during operation can be expressed quantitatively through different time functions. Mathematical procedures and statistical laws allow to assess the precise analytical relations between these functions. Referring to a generic system or component is a common experience that its duration in-service is not predictable in a deterministic way. This consideration identifies the lifetime (or time to failure) of the component as a continuous random variable, susceptible to a statistical description, whose estimate is crucial in the design phase, or in any case before the commissioning of equipment. In a second stage, the actual values of reliability must be compared with the forecast values arising from the theoretical statistical model used. This comparison allows assessment of the goodness-of-fit level and the confidence level of the prediction model, in order to validate it for any future equipment redesigns or for similar equipment. In this context, the present work is aimed at identifying the most appropriate statistical tools for the comparison above, and then to assess the reliability of the forecast data, compared to the real performance of a reliability system. For this purpose, a literature analysis was conducted, with a dual purpose: The identification of statistical models most commonly used to describe the reliability function of a system; to provide a choice of appropriate indicators and effective tests for assessing the confidence of the statistical models for reliability scopes. The models identified were then applied, as an example, to the real case of a catalytic cracking catalyst with the fluidized bed of a petrochemical plant. The results obtained from the case study, discussed in the final section of the work, offer many points of comparison between the various statistical models as well as a first overview of their reliability.

Maintenance strategy design in a sintering plant based on a multicriteria approach

Maintenance strategy design greatly contributes to ensure the pre-established production capacity of an industrial system and to reduce organisation cost, without compromising customer satisfaction resulting in loss of market share. The focus of the present research is a new model for maintenance policy developed and implemented in a case study. The new approach is focused on the adequate distribution of maintenance budget to system units according to the main factors determining availability and maintenance of equipment. These factors are summarised through appropriate indices, adjusted through a multicriteria method, the analytic hierarchy process (AHP), depending on the importance level of each considered factor and unit of the system. The results can be used as a support for allocation of budgets to maintenance activities, identifying machines or units that are strategic to ensure production. The model has been applied on a real industrial plant.