Development of a Multi-Body Nonlinear Model for a Seat-Occupant System

A car seat is an important component of today\u27s cars, which directly affects ride comfort experienced by occupants. Currently, the process of ride comfort evaluation is subjective. Alternatively, the ride comfort can be evaluated by a series of objective metrics in the dynamic response of the occupant. From previous studies it is well known that the dynamic behavior of a seat-occupant system is greatly affected by soft nonlinear viscoelastic materials used in the seat cushion. Therefore, in this research, especial attention was given to efficiently modeling the behavior of seat cushion. In the first part of this research, a phenomenological nonlinear viscoelastic foam model was proposed and its ability to capture uniaxial behavior of foam was investigated. The model is based on the assumption that the total stress can be decomposed into the sum of a nonlinear elastic component, modeled by a higher order polynomial of strain, and a nonlinear hereditary type viscoelastic component. System identification procedures were developed to estimate the model parameters using uniaxial cyclic compression data from experiments conducted at different rates on two types of low density polyurethane foams and three types of high density CONFOR foams. The performance of the proposed model was compared to that of other traditional continuum models. For each foam type, it was observed that lower order models are sufficient to describe the uniaxial behavior of the foam compressed at different rates. Although, the estimated model parameters were functions of the input strain rate. Alternatively, higher order comprehensive models, with strain independent parameters, were estimated as well. The estimated comprehensive model predicts foam responses under different compression rates. Also, a methodology was proposed to predict the stress-response of a layered foam system using the estimated models of each foam in the layers. Next, the estimated foam model was incorporated into a single-degree of freedom foam-mass model which is also the simplest model of seat-occupant systems. The steady-state response of the system when it is subjected to harmonic base excitation was studied using the incremental harmonic balance method. The incremental harmonic balance method was used to reduce the time required to generate the steady-state response of the system. The incrementa

Bio-Treatment of an Acidic Industrial Wastewater: Tana Explosive Factory

Tana is one of the Sudanese Military industries. Manufacturing different types of chemical i.e. (TNT, DNT, and MNT). The pH of the acidic wastewater is 1.7 was mixed together with 10% sodium hydroxide lye and neutralized under agitation in neutralizing tank. After neutralization the pH of water reached the value of 6.In this study anew bio treatment is applied to treat acidic wastewater by using moringa oleifera leaves after grinding and mixing in a tank the result indicated that significant increase in pH from1.7 to5.8 in 3 hours, and with 10%added sodium hydroxide (NaOH) pH value reached 6 that without salt sedimentation and low cost of treatment. The Moringa Oleifera leaves showed good treatment properties especially when used for acidic wastewater of pH value (1.7). Moringa Oleifera leaves can raise pH value to (5.8) in three hours. It is highly recommended that realistic visibility study must be carried out to design and apply the manufacture of the tablets of Moringa

Synthesis and characterization of nano and microparticles of biopolymers for food packaging applications

Programa Oficial de Doutoramento en Física Aplicada. 5021V01[Abstract] The main aim of this thesis is the preparation and characterization of nano and microparticles of selected biopolymers addressed for food packaging and active food packaging applications. Two biopolymers have been selected for the nano and microparticles preparations: poly(3-hydroxybutyrate-co-3- hydroxyvalerate) (PHBV) and starch. The results for the PHBV showed spherical porous particles with wide variety of size distribution depending on the selected techniques and the procedure conditions. Starches from different botanical origins were used for preparing starch nanoparticles and starch/quercetin nanoparticles using the nanoprecipitation technique. The loading capacity, the release profile of the quercetin from the nanoparticles and therefore the antioxidant activity changed by changing the starch origin. Starch microparticles with donut-shaped morphology were prepared from starches of two different botanical origins and then loaded to thermoplastic starch (TPS) films. The TPS loaded with microparticles showed better thermal stability, less water vapour and oxygen transmission rates. The donut-shaped microparticles were also used as a carrier for quercetin within TPS films. The quercetin kept releasing during 4 to 11 days depending on the starch origin. The produced nano and microparticles provide many possibilities for improving some properties of the biopolymeric packaging films with the capacity for active delivery function for reasonable periods.[Resumen] El objetivo de esta tesis es la preparación y caracterización de nano y micropartículas de biopolímeros para su uso en envases y embalajes alimentarios convencionales y activos. Se seleccionaron dos biopolímeros: Poli(3-hidroxibutirato-co- 3-hidroxivalerato) (PHBV) y almidón. Para el PHBV, los resultados mostraron partículas esféricas y porosas con una amplia variedad en la distribución de tamaños, en función de la técnica utilizada y las condiciones de preparación. Se han utilizado también almidones de diferentes orígenes botánicos en la preparación de las nanopartículas tanto de almidón solo como de almidón cargado con quercetina. La capacidad de carga, el perfil de liberación y el consiguiente cambio en la actividad antioxidante de la quercetina varía según el origen del almidón. Se prepararon micropartículas con forma de donut de dos almidones de diferente origen para su uso como relleno en filmes de almidones termoplásticos (TPS). Estos TPS cargados con las micropartículas mostraron mejor estabilidad térmica y menores tasas de transmisión de vapor de agua y oxígeno. Estas micropartículas se utilizaron también como portadores de quercetina dentro de los TPS. Las nano y micropartículas producidas proporcionan muchas posibilidades para mejorar algunas de las propiedades de los biofilmes usados en la industria de envase y embalaje alimentario y les confieren capacidad de liberación de compuestos activos durante periodos razonables.[Resumo] O obxectivo desta tese é a preparación e caracterización de nano e micropartículas de biopolímeros para o seu uso en envases e embalaxes alimentarios convencionais e activos. Seleccionáronse dous biopolímeros: Poli(3-hidroxibutiratoco- 3-hidroxivalerato (PHBV) e amidón. No caso do PHBV, os resultados amosaron partículas esféricas e porosas cunha ampla variedade na distribución de tamaños en función da técnica utilizada e as condicións de preparación. Tamén, utilizáronse amidóns de orixes botánicas diferentes na preparación das nanopartículas, tanto as de só amidón como as de amidón cargado con quercetina. A capacidade de carga, o perfil de liberación e o cambio na actividade antioxidante da quercetina varía segundo a orixe do amidón. Ademais preparáronse micropartículas coa forma de donut de dous amidóns de orixe botánica diferente para o seu uso como recheo en filmes de amidóns termoplásticos TPS. Estes amosaron mellor estabilidade térmica e menores taxas de transmisión de vapor de auga e osíxeno. Estas micropartículas usáronse tamén como portadores de quercetina dentro dos filmes de TPS. As nano e micropartículas producidas proporcionan moitas posibilidades de mellora de algunha das propiedades dos biofilmes empregados na industria do envase e embalaxe alimentario, conferíndolles capacidade de liberación de compostos activos durante períodos razoables de tempo

Evolving Heterogeneous And Subcultured Social Networks For Optimization Problem Solving In Cultural Algorithms

Cultural Algorithms are computational models of social evolution based upon principle of Cultural Evolution. A Cultural Algorithm are composed of a Belief Space consisting of a network of active and passive knowledge sources and a Population Space of agents. The agents are connected via a social fabric over which information used in agent problem solving is passed. The knowledge sources in the Belief Space compete with each other in order to influence the decision making of agents in the Population Space. Likewise, the problem solving experiences of agents in the Population Space are sent back to the Belief Space and used to update the knowledge sources there. It is a dual inheritance system in which both the Population and Belief spaces evolve in parallel over generations. A question of interest to those studying the emergence of social systems is the extent to which their organizational structure reflects the structures of the problems that are presented to them. In a recent study [Reynolds, Che, and Ali, 2010] used Cultural Algorithms as a framework in which to empirically address this and related questions. There, a problem generator based upon Langton\u27s model of complexity was used to produce multi-dimensional real-valued problem landscapes of varying complexities. Various homogeneous social networks were then tested against the range of problems to see whether certain homogeneous networks were better at distributing problem solving knowledge from the Belief Space to individuals in the population. The experiments suggested that different network structures worked better in the distribution of knowledge for some optimization problems than others. If this is the case, then in a situation where several different problems are presented to a group, they may wish to utilize more than one network to solve them. In this thesis, we first investigate the advantages of utilizing a heterogeneous network over a suite of different problems. We show that heterogeneous approaches begin to dominate homogeneous ones as the problem complexity increases. A second heterogeneous approach, sub-culutres, will be introduced by dividing the social fabric into smaller networks. The three different social fabrics (homogeneous, heterogeneous and Sub-Cultures) were then compared relative to a variety of benchmark landscapes of varying entropy, from static to chaotic. We show that as the number of independent processes that are involved in the production of a landscape increases, the more advantageous subcultures are in directing the population to a solution. We will support our results with t-test statistics and social fabric metrics performance analysis

ISLAMIC ELEMENTS IN TRADITIONAL INDONESIAN AND MALAY THEATRE

From the earliest times, traditional theatre in Southeast Asia has been shaped by a wide range of religious and cultural influences—those deriving from animism, Hinduism, Buddhism, Islam, as well as from Chinese and western traditions. The overwhelming influences, especially of Hinduism, have had the tendency to obscure contributions from the Middle- and Near-East. The view that Islam, with rare exceptions, prohibits performing arts has resulted in a negligence of these arts forms in Muslim societies with the possible exception of Indonesia. This paper highlights significant elements of Islamic culture that have shaped Indonesian and Malay traditional theatre through the adaptation of borrowed genres such as taziya, as well as locally created styles of shadow play (wayang kulit) and the doll-puppet theatre (wayang golek); the use of important themes from Islamic literature, in particular thosederived from Hikayat Amir Hamza; as well as esoteric interpretationsof certain episodes originally derived from pre-Islamic sources,including the Mahabharata, in terms of Sufism to make them both highly meaningful and acceptable to Muslim audiences

A patient-specific adaptation of the Living Human Heart Model in application to pulmonary hypertension

The Living Heart Project aims to offer medical practitioners and researchers a full-heart electromechanical computational platform to explore and assess clinical cases pertaining to the left ventricle (LV), and the less addressed right ventricle (RV). It does not, however, provide an easy solution to applying this platform to patient-specific cases that account for a large variability among cases. We, therefore, present a solution to modify the Living Human Heart Model (LHHM) to obtain a patient-specific geometry using the thermal expansion method, with iteratively adjusted parameters that accurately simulate the case of a 72-year-old female patient suffering from secondary pulmonary hypertension caused by mitral valve regurgitation (MR). The patient underwent MV replacement and we simulate the heart from magnetic resonance imaging (MRI) images prior to surgery and 3 days following surgery. A mean pulmonary arterial pressure (mPAP) of approximately 64 mmHg was demonstrated before surgery, along with a severe lack of coaptation of the mitral valve. Reduced function of the cardiac chambers is exhibited in the reduced ejection fraction (EF). We also demonstrate left-side failure, an increase in Global Longitudinal Strain (GLS) and the location of maximum cardiac wall stress located at the mid anterolateral wall of the RV where dilation traditionally manifests. Comparison of patient geometry pre-operation and post-surgery showed a change in shape of the Tricuspid Annulus (TA) in systole. A rigid constraint across the TA was used to simulate an annuloplasty ring, and an increase in ring-widening forces was observed post-operation, with a significant reduction in forces being present in contractile forces on the ring. This model led us to conclude that the patient will likely develop TV annular dilatation and subsequent regurgitation in the absence of intervention. We verify the use of the LHHM for assessing potential remodeling and subclinical RV dysfunction, and subsequent intervention and attenuation of pulmonary hypertension by a mitral valve replacement. The lack of personalization and wide variability have remained a significant reason for the slow adoption rate of computational tools among medical practitioners, but we see this work as a substantial addition to computational cardiology, and foresee a closer integration of such technology to mainstream application among members of the medical community