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There is a growing requirement within QinetiQ to develop models for assessments when there is very little experimental data. A theoretical approach to developing equations of state for geological materials has been developed using Quantitative Structure Property Modelling based on the Porter-Gould model approach. This has been applied to well-contr...
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... The work contained within this article preceded Dirlewanger et al.'s (2017) study and led to the revised test arrangement where gabions are placed on a freely draining gravel base rather than directly onto concrete, reducing the susceptibility of the gabion system to overturn. Localised variations in moisture content will also affect the pressure-volume response of the soil and hence its penetrative resistance (Barr et al., 2016;Børvik et al., 2015;Church et al., 2015). Børvik et al. (2015) found that for 0-2 mm sand, the change in moisture content from dry to fully saturated can lead to an increase of up to 100% in the penetration of small arms rounds. ...
Gabion structures are widely used for force protection as they enable locally available material to be used, reducing logistical expense. The soil fill within these structures provides the blast and ballistic resistance; hence, any localised variation in the contained soil can potentially lead to reductions in protective capability. Specifically, built gabion structures were monitored in internal and external environments to assess the variation of soil moisture content and density over a full year and with changing weather conditions. The gabions were filled with fine sand according to manufacturer’s instructions. Internal and external moisture content readings were recorded at regular intervals, and a continuously monitoring weather station was installed to collect comparative data. LIDAR scanning was used to record the shape and volume of the gabions to estimate variations in the density of the soil fill. The data indicate that moisture content can vary by over 20% between the top and base of the gabion, and by over 5% from face to face and between readings depending on recent weather conditions, while the core of the gabions remains relatively unaffected. This leads to localised variations in density which can impact on both the ballistic performance and blast resistance of the structure.
... However, its complexity and high time and labor cost have resulted in only a few related studies in the literature that either focused on single-room climate chamber or test cells experiments. This includes IEA Annex 21 (Lomas et al. 1997), IEA Task 22 (Palomo del Barrio and Guyon, 2003;2004), and PASSYS project (Jensen, 1993;Clarke et al., 1993). It also applies to realistic full-scale residential building experiments as done in IEA Annex 58 (Strachan et al., 2015;2016). ...
... Todos realizan una vida independiente, no están discapacitados físicamente y no presentan patología sensorial importante (sordera, problemas visuales no corregidos, etc.). Los criterios de exclusión fueron: -Padecer depresión moderada-grave: se tomaron dos criterios, la escala geriátrica de depresión (GDS) de 30 ítems de Yesavage [44], con punto de corte 17/18 (indicando que > 17 implica posible depresión), y la valoración clínica del profesional sanitario. Los sujetos con depresión leve podían, a juicio del profesional, ser admitidos en el estudio. ...
Association of quality of life with episodic memory performance. Study in elderly without cognitive impairment
Introduction. Health related quality of life (HRQL) measures health status based on the self-assessment of health-related well-being.
Aims. To study how HRQL relates to cognitive performance, memory and subjective variables such as depression and perception of everyday forgetfulness, and to analyze predictors of HRQL.
Subjects and methods. Consecutive sample of 3456 elderly without cognitive impairment who attend preventive activities (mean age: 71.41 ± 4.7; range: 65-89). Assessment: HRQL with Nottingham Health Profile (NHP); cognitive performance
(Mini Cognitive Examination MCE), daily episodic memory (RBMT) and associative memory (PPAA), perception of everyday forgetfulness (Questionnaire MFE) and depression (GDS).
Results. Using factorial analysis we found two factors (51.49% of the variance): variables with subjective assessment (NHP, MFE and GDS), and variables with objective assessment (MCE, RBMT, PPAA). HRQL correlates positively with all variables, subjective and objective. In the study of predictors (hierarchical linear regression, R2 = 0.29, p < 0.001), subjective variables are significant, and also on a lesser scale, the socio-
demographic ones (age, sex, education) and the MCE. Daily and associative memory are not predictors in the final model.
Conclusions. In elderly without cognitive impairment, HRQL is mainly associated with subjective variables such as depression and perception of forgetfulness. Episodic memory is an indirect indicator of quality of life. Therefore, with interventions in elderly such as memory training, quality of life would be affected if we modify the mood state and the subjective perception of forgetfulness.
Key words. Cognitive performance. Episodic memory. Everyday forgetfulness. Health related quality of life. Predictors. Subjective memory complaints.
... Las pruebas utilizadas en la evaluación son: -Escala Geriátrica de Depresión (GDS), de Yesavage et al 49,50 , que ha sido validada para la poblacion española 51 , con un punto de corte de 17/18. Esta escala ha sido utilizada por su autor y por otros autores no sólo como método de cribado, sino también para valorar los efectos del tratamiento de la depresión 52 -Cuestionario de Salud General de Goldberg 58,59 , de 28 ítems (GHQ-28), que se utiliza para la detección de alguna probable enfermedad psiquiátrica y califica a los sujetos en caso/no caso. ...
IntroductionDeficits in memory performance in later life are frequent and well documented. There are several terms that refer to this phenomenon and the most commonly used is age associated memory impairment (AAMI). Currently, cognitive or memory training programmes are increasingly being used to treat this deficit. The Department of Health of the City of Madrid has developed a multifactorial memory training programme for older people which is carried out in 13 City Health Centres.Objectives
To study the effects of this programme in a sample of users aged more than 65 years with memory impairment, to determine the persistence of the results after 6 months, and to investigate predictors of results.Patients and methodThe sample was composed of 1,083 subjects who underwent memory training. The subjects were assessed before and after training and after 6 months. Among other tests, the Mini Examen Cognoscitivo (MEC), the Rivermead Behavioural Memory Test (RBMT), the Geriatric Depression Scale (GDS), and Memory Failures of Everyday (MFE) were used. The training method used (UMAM method) was developed by the Memory Unit of the City of Madrid.ResultsObjective memory improvement for the entire group was 40% (Cohen’s «d», 0.95) and 77% of the subjects improved. Seventy- five percent of the subjects improved in subjective memory functioning (Cohen’s «d», 0.64). Improvement in mood was also observed. These changes were maintained after 6 months. The predictive variables were age, MEC, GHQ and GDS scores before training, but the percentage of explained variance was very low.Conclusions
The multifactorial memory training programme, UMAM, improves objective and subjective memory functioning in older people with memory impairment and the benefits persist after 6 months. The predictive value of the variables studied is low.
... In the second phase of PASSYS, main emphasis was devoted to empirical model validation. The complete description of the resulting methodology can be found in [4] and more condensed in [5,6]. ...
... Checking model validity intends to test the model performances by identification of significant disagreements between measurements and simulations. Different studies have been carried out in the past with the attempt to establish methods for rigorous model validity test [1][2][3][4]7,8]. In the framework of the IEA Task 22, checking model validity involves the following. ...
... Three different techniques are generally used to estimate these model output bounds over Θ. They are based on Monte-Carlo methods, differential sensitivity and stochastic sensitivity analysis [4,7], respectively. Two of them, those that do not require modifications of the simulation codes, have been applied in the framework of the IEA Task 22: the standard Monte-Carlo approach and the method founded on sensitivity analysis. ...
A new methodology for empirical model validation has been proposed in the framework of the Task 22 (Building Energy Analysis Tools) of the International Energy Agency. It involves two main steps: checking model validity and diagnosis. First step aims to test the model performances by identification of significant disagreements between measurements and simulations. It rests on both residuals analysis techniques and comparisons between model outputs uncertainty bands and measurements uncertainty intervals. Second step intends to explain the differences observed between model simulations and measurements. A new approach for models diagnosis has been proposed. It rests on the analysis of the model parameters space. The main objective is to identify the changes in parameters values that are required for a significant model behaviour improvement. Diagnosis is then provided by comparison of such results with the knowledge we have about both the actual system and the model itself. Main mathematical tools for diagnosis are sensitivity analysis and optimisation techniques. The methodology and the underlying methods we are proposing are presented in the first part of the paper. In the second part, they are applied for testing modelling hypothesis in the framework of the thermal analysis of an actual building.
... The power car had a mass of 91 Mg, twice that of a passenger car [2]. The strength of the power car was twice that of a passenger car, consistent with assumptions described by Mayville et al. [3] in collision dynamics studies investigating locomotive crashworthiness. There was a 0.5 m gap between cars. ...
A calculational approach has been developed for crashworthiness analyses of train sets that is practical to perform using desktop workstations. The approach is organized into three steps. First, a detailed model of the train car is developed and the response of the car is calculated for various collision scenarios. Results of this first step highlight the response mechanism of the car and provide data on the crush strength of the car over a range of responses. The second step uses the crush response of the detailed model to develop simpler models that can be used to study the collision dynamics between cars. Using these simpler models allows calculation of the response of a set of several train cars in a collision or derailment scenario and includes interactions between cars. These calculations show how much crush each car experiences and provide velocity histories for different locations along the train set. The third step is to use the velocity histories for the cars to calculate the response of an occupant in the train. For this step, two procedures are described. First, a crash dummy and a few seats are modeled in detail and a simplified model is used for the surrounding car structure. Velocities are applied to the car structure and the secondary impact response of the occupant with the adjacent seats is calculated. Injury measures such as the head injury criterion (HIC) are obtained from the calculated acceleration records of the occupant head. The second procedure estimates injury by using relationships between secondary impact velocity, HIC, and injury. Examples of calculations for each of these steps are shown to illustrate this approach.
In the April 2017 edition of this journal, the Author published a theoretical Technical Note in the peer-reviewed section of the journal. Commentary on that Technical Note was provided in Forum section of that same issue by Jeff Parnell of the NSW Department of Planning and Environment. The primary concerns were that simplification of the method could result in underestimation of noise impacts. This reply aims to allay some of those concerns.
Measurement procedures for calculating sound power levels of mining equipment often include modifications to the formal requirements of ISO6395 for practicality and safety purposes on site. The formal procedures involving six measurement points are necessary for homologation certification against contractual requirements for the supply of mining equipment. This is a relatively minor percentage of the total number of sound power tests conducted within the Australian coalfields, however, as most testing is for ongoing compliance purposes where consent conditions require sound power testing of mining fleets every 2 or 3 years. Acoustical consultants have reported accurate results by using a reduced 4-point measurement regime which enables consent conditions to be met without undue disturbance to a mine’s operations. A theoretical basis for omission of two of the ISO measurement points is presented, as well as demonstration that a 2-point measurement regime is mathematically equivalent to the 4-point method. A correction for using sound pressure instead of sound intensity for calculation of sound power level is also calculated.
