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HEAVY-DUTY TRUCK PLATOONING ON HILLY TERRAIN: METHODS FOR ASSESSMENT AND IMPROVEMENTMiles J Droege (11128536) 22 July 2021 (has links)
Class 8 heavy-duty truck platooning has demonstrated significant fuel economy benefits on routes with road grade less than±2% in literature, but there is little to no platooning research on routes with road grade greater than±2% - which make up a significant portion of U.S. highways. Therefore, the effort described in this thesis is aimed at assessing currently available two-truck platoon control strategies as well as developing new strategies to improve platoon performance on hilly terrain. Specifically, the strategies tested in this work include four types of lead truck speed control strategies and two types of platoon transmission shifting strategies. These strategies are tested using two experimentally validated heavy-duty, two-truck platoon simulation approaches where each approach has its own advantages and disadvantages. The trends observed from these two simulation approaches indicate that the lead truck speed control and transmission shifting strategies have a significant effect on the platoon fuel economy and gap control performance when the platoon operates on a hilly terrain route.
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Två hjärtan : Upplevelser av att ta emot och bära ett mekaniskt hjälphjärta / Two hearts : Experiences of receiving and carrying a ventricular assist deviceBergstedt, Mikaela, Börjesson, Hanna January 2020 (has links)
Personer med hjärtsvikt överlever idag längre än tidigare och allt fler utvecklar grav hjärtsvikt. Mekaniska hjälphjärtan kan bli ett alternativ för personer med långt framskriden hjärtsvikt. Insättning av mekaniska hjälphjärtan ger positiva effekter i form av minskad symtombörda, bättre fysisk funktion samt ökad livslängd. Insättningen av ett mekaniskt hjälphjärta kan dock påverka livskvaliteten negativt. Identifiering av upplevelser som påverkar livskvaliteten hos personer med ett mekaniskt hjälphjärta är av vikt för att kartlägga relevanta omvårdnadsåtgärder. Syftet med studien var att belysa upplevelser av livskvalitet hos personer med hjärtsvikt i samband med behandling av ett mekaniskt hjälphjärta. En allmän litteraturstudie med induktiv ansats genomfördes och resultatet baserades på nio resultatartiklar. Resultatet visade att personers livslängd ökade liksom deras fysiska funktion. Dock påverkas livskvaliteten negativt av restriktioner och känslor som påverkar synen på sig själv. Personerna upplevde känslor som minskad autonomi, förlorad identitet, förlorad kontroll och känslor av att vara bunden i vardagen. Psykiskt och praktiskt stöd ansågs som viktigt. Personer upplevde även brist på information i beslutsfattandeprocessen och innan utskrivning. Med ståndpunkt i denna studiens resultat kan personer med mekaniska hjälphjärtan gagna från mer information och patientutbildning samt erbjudas psykologiskt-, socialt- och praktiskt stöd. / People with heart failure are now surviving longer than before and several people develop severe heart failure. Ventricular assist devices can be an option for people with advanced heart failure. Implantation of a ventricular assist device has positive effects in the form of reduced symptom burden, improved physical function and increased life expectancy. However, life with a ventricular assist device can adversely affect the quality of life. Identifying experiences that affect the quality of life of people with a ventricular assist device is important to identify relevant nursing interventions. The purpose of this study was to illustrate experiences of quality of life in people with heart failure in correlation with the treatment of a ventricular assist device. A general literature study with an inductive approach was conducted and the results were based on nine resultarticles. Results showed that people’s life expectancy increased as did their physical function. However, the quality of life is negatively affected by restrictions and emotions that affect the view of oneself. Individuals experienced feelings such as reduced autonomy, lost identity, lost control and feelings of being bound in everyday life. Psychological and practical support was considered important. People also experienced a lack of information in the decision-making process and before discharge. Based on the results of this study, people with ventricular assist devices can benefit from more information and patient education and also be offered psychological-, social- and practical support.
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Using Music in Teaching Social Skills to Mentally Retarded SubjectsBarron-Johnson, Tamara 01 May 1987 (has links)
The purpose of this study was to determine the extent to which Melodies to Assist Social Interaction (MASI) would affect the social skills performance of the educable mentally retarded.
The study employed a pretest-posttest control group design with an N of 27 mentally-retarded subjects. It also employed a one-group pretest-posttest design with an N of 8 non-mentally retarded subjects.
All of the subjects received a pre- and post-score for their social skills performance level. Nineteen of the mentally-retarded subjects and all eight non-mentally retarded subjects received the MASI social skills teaching program as part of their regular curriculum.
The pre- and post-treatment performance was analyzed by a correlated means t-test. An analysis of covariance was used in which the posttest means were compared using the pretest means as a covariate.
It was concluded that MASI did not have an impact, positive or negative, on the social skills performance level of the subjects.
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Modeling and Simulation of Lane Keeping Support System Using Hybrid Petri NetsPadilla, Carmela Angeline C. 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In the past decades, the rapid innovation of technology has greatly affected the automotive industry. However, every innovation has always been paired with safety risks that needs to be quickly addressed. This is where Petri nets (PNs) have come into the picture and have been used to model complex systems for different purposes, such as production management, traffic flow estimation and the introduction of new car features collectively known as, Adaptive Driver Assistance Systems (ADAS). Since most of these systems include both discrete and continuous dynamics, the Hybrid Petri net (HPN) model is an essential tool to model these. The objective of this thesis is to develop, analyze and simulate a lane keeping support system using an HPN model. Chapter 1 includes a brief summary of the specific ADAS used, lane departure warning and lane keeping assist systems and then related work on PNs is mentioned. Chapter 2 provides a background on Petri nets. In chapter 3, we develop a discrete PN model first, then we integrate continuous dynamics to extend it to a HPN model that combines the functionalities of the two independent ADAS systems. Several scenarios are introduced to explain the expected model behavior. Chapter 4 presents the analysis and simulation results obtained on the final model. Chapter 5 provides a summary for the work done and discusses future work.
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Optimizing Cardiac Transplantation Outcomes in Children with VADs: How Long Should the Bridge Be?Riggs, Kyle 25 July 2019 (has links)
No description available.
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Left Ventricular Hemodynamics with Reduced Ejection Fraction: An In-Vitro Piv Study using an Implanted Assisting DeviceJermyn, Elizabeth 14 December 2018 (has links)
A left ventricular assist device is a mechanical pump implanted in patients with heart failure that continuously takes blood from the left ventricle and delivers it to the aorta, thus decreasing ventricular load. The device is typically considered as a ‘bridge to transplant’, i.e. as a temporary therapy, and involves several risks. Modified ventricular hemodynamics due to a heart pump implantation is studied in-vitro using an elastic ventricle. The ventricle is incorporated into a pulse duplicator setup, which prescribes realistic pulsatile inflow/outflow to mimic a weak ejection fraction. A continuous axial pump mimics a ventricular assist device and its effect on the ventricular hemodynamics is investigated as a function of the pump flow suction. Using particle image velocimetry, pump flow effectiveness at providing unloading on the ventricle and increasing ejection is observed and understanding if proper recirculation of the myocardium down to the apex is restored under varying flow rate.
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Concept design and In Vitro evaluation of a novel dynamic displacement Ventricular Assist DeviceStenberg, Mattias January 2006 (has links)
Ventricular Assist Devices (VADs) are mechanical pumps used to off-load a deceased heart, primarily in late stage congestive heart failure patients. VAD employment may facilitate cardiac recovery, but most often provides time before a suitable heart transplant can be found. Lately, long term use VAD systems have been introduced as an alternative to a heart transplant. Traditionally, design of VADs has employed either displacement based pump technologies or radial-flow pumps, also known as rotodynamic pumps. A displacement pump induces a mechanical force on a fluid contained within a defined space, hence giving it motion. Radial-flow pumps impart momentum to a fluid, most often by placing a rotating device in the fluid. This thesis introduces a novel pumping concept, combining features from both displacement and radial-flow pumps. A first prototype, the VivicorTM pump, has been designed, fabricated and evaluated In Vitro, the results reported in this thesis. The In Vitro evaluation of the VivicorTM pump provides evidence of a pump with mechanical self-regulation based on pump pre-load level, much like a displacement pump. The VivicorTM pump also displays pulsating outflow in combination with an inflow both during pump systole and diastole. The latter provides potential advantages over traditional displacement pumps as smaller cannulae or catheters can be used, facilitating miniaturization. Continuos filling throughout the pumping cycle also require less pressure to be exerted on the fluid, compared to displacement pumps, limiting the risk of mechanical damage to the pumped fluid. The In Vitro evaluation has also provided further insights on necessary design modifications in the second-generation VivicorTM prototype, currently planned. The VivicorTM pumping technology is highly interesting for further development and evaluation for use in ventricular assist applications. / QC 20101129
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Parameter Optimisation of EPAS Using CAEBhattacharyya, Shounak, Sivaramakrishnan, Suraj January 2019 (has links)
To keep up with technological as well as logistical challenges of the modern automobile market, major car manufacturing firms have resorted to virtual simulation tools. This enables the development as well as validation of vehicular models much before resources are invested into a new physical prototype.This project focuses on the development of a tool that would help in optimising the handling parameters of a vehicle. This is achieved by creating an optimization routine for tuning the various parameters of the Electronic Power Steering (EPAS). This process is usually done manually, by on-track testing, due to the difficulties in correlating Subjective Assessments (SA) with Objective Metrics (OM). Automating this process would help to reduce the overall research and development time, by providing a baseline tune for the EPAS parameters which could then be finely tweaked by manual track testing.The tool is built by interfacing various software in a multi-objective optimisation environment known as ModeFrontier. The modelling and simulations are performed in IPG CarMaker, with the post processing of the results taken care of by Sympathy for Data. Multiple optimization algorithms were tested to achieve the best optimisation routine. The EPAS parameters, namely the Basic Steering Torque, Active Return and Active Damping, act as the input to the optimization routine. The outputs of the model are the Objective Metrics, which provide a clear indication of the dynamic performance of a component. These metrics are optimized to _t the Steering DNA structure, which uniquely describes the attributes of a vehicle. The final optimised vehicle is manually tested at the track, to determine the real driving feel. / För att upprätthålla ett positivt momentum i såväl tekniska som logistiska utmaningar på dagens bilmarknad har stora biltillverkare börjat använda sig av virtuella simuleringsverktyg. Dessa verktyg möjliggör utveckling av diverse fordonsmodeller långt innan resurser investeras i en fysisk prototyp. Detta projekt fokuserar på utvecklingen av ett verktyg som potentiellt kan hjälpa att optimera dynamiska beteendeparametrar för ett fordon. Detta uppnås genom att skapa en optimeringsrutin för att ställa in de olika parametrarna för den elektroniska servostyrningen (EPAS). Denna process görs vanligtvis manuellt, genom test på provbana, på grund avsvårigheterna att korrelera subjektiva bedömningar (SA) med objektiva mätetal (OM). Att automatisera denna process kan bidra till att minska den övergripande forsknings- och utvecklingstiden genom att tillhandahålla en baslinje för EPAS-parametrarna som i efterhand kan finjusteras genom manuell justering på provbana. Verktyget är byggt genom att ansluta olika program i en optimeringsmiljö som kallas ModeFrontier. Modellering och simuleringar utförs i IPG CarMaker, med efterbehandling av resultaten i Sympathy for Data. Flera optimeringsalgoritmer testades för att uppnå bästa optimeringsrutinen. EPAS-parametrarna består av det grundläggande styrmomentet, aktiv retur och aktiv dämpning, och fungerar som invärden till optimeringsrutinen där utvärdera från modellen är objektiva mätetalen, vilket ger en tydlig indikation på den dynamiska prestandan hos en komponent. Dessa mätvärden optimeras för att passa Steering DNA-strukturen, som unikt beskriver egenskaperna hos ett fordon. Det slutliga optimerade fordonet testas manuellt på provbana för att bestämma den verkliga körkänslan.
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A Bench Top Study Of The Optimization Of Lvad Cannula Implantation To Reduce Risk Of Cerebral EmbolismClark, William D 01 January 2012 (has links)
Physical bench top experiments are performed to validate and complement ongoing computational fluid dynamics (CFD) analyses of ventricular assist device (VAD) circulation. VADs are used in patients whose hearts do not function to their maximum potential due advanced stages of heart disease and, consequently, are unable to adequately supply blood to the systemic circulation. VADs are commonly utilized as a bridge-to-transplantation, meaning that they are implanted in patients while waiting for a heart transplant. In such cases of long term utilization of VADs, it has been reported in the literatures that thrombo-embolic cerebral events occur in 14-47% of patients over the period of 6 to 12 months. This is a result of thrombus forming despite the use of anticoagulants and advances in VAD design. Accepting current rates of thrombo-embolisms, the main objective of the project is to identify and propose an optimal surgical cannula implantation orientation aimed at reducing the rate of thrombi reaching the carotid and vertebral arteries and thus reduce the morbidity and mortality rate associated with the long term use of VADs to patients suffering from advanced heart failure. The main focus of the experiment is on the physical aspect using a synthetic anatomically correct model constructed by rapid prototyping of the human aortic arch and surrounding vessels. Three VAD cannula implantation configurations are studied with and without bypass to the left carotid artery or to the Innominate artery with ligation of the branch vessel at its root. A mixture of water and glycerin serves to match blood viscosity measured with a rotating cone-plate viscometer. The Reynolds number in the ascending aorta is matched in the flow model. A closed loop mock circulatory system is then realized. In order to match the Reynolds number in the ascending aorta and LVAD cannula with that of the CFD model, a volumetric flow rate of 2.7 liters per minute is supplied through the synthetic VAD cannula and 0.9 liter per minute is supplied to the ascending aorta. Flow rates are measured using rotary flow meters and a pressure sensor is used to ensure a mean operating pressure of 100 mmHg is maintained. Synthetic acrylic blood iv clots are injected at the inlet of the VAD cannula and they are captured and counted at the vertebral and carotid arteries. The sizes of the thrombi simulated are 2, 3.5 and 5 mm which are typical of the range of diameters encountered in practice. Nearly 300 particles are released over 5 separate runs for each diameter, and overall embolization rates as well as individual embolization rates are evaluated along with associated confidence levels. The experimental results show consistency between CFD and experiment. Means comparison of thromboembolization rates predicted by CFD and bench-top results using a Z-score statistic with a 95% confidence level results in 22 of 24 cases being statistically equal. This study provides confidence in the predictive capabilities of the bench-top model as a methodology that can be utilized in upcoming studies utilizing patient-specific aortic bed model.
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Suction Detection And Feedback Control For The Rotary Left Ventricular Assist DeviceWang, Yu 01 January 2013 (has links)
The Left Ventricular Assist Device (LVAD) is a rotary mechanical pump that is implanted in patients with congestive heart failure to help the left ventricle in pumping blood in the circulatory system. The rotary type pumps are controlled by varying the pump motor current to adjust the amount of blood flowing through the LVAD. One important challenge in using such a device is the desire to provide the patient with as close to a normal lifestyle as possible until a donor heart becomes available. The development of an appropriate feedback controller that is capable of automatically adjusting the pump current is therefore a crucial step in meeting this challenge. In addition to being able to adapt to changes in the patient's daily activities, the controller must be able to prevent the occurrence of excessive pumping of blood from the left ventricle (a phenomenon known as ventricular suction) that may cause collapse of the left ventricle and damage to the heart muscle and tissues. In this dissertation, we present a new suction detection system that can precisely classify pump flow patterns, based on a Lagrangian Support Vector Machine (LSVM) model that combines six suction indices extracted from the pump flow signal to make a decision about whether the pump is not in suction, approaching suction, or in suction. The proposed method has been tested using in vivo experimental data based on two different LVAD pumps. The results show that the system can produce superior performance in terms of classification accuracy, stability, learning speed, iv and good robustness compared to three other existing suction detection methods and the original SVM-based algorithm. The ability of the proposed algorithm to detect suction provides a reliable platform for the development of a feedback control system to control the current of the pump (input variable) while at the same time ensuring that suction is avoided. Based on the proposed suction detector, a new control system for the rotary LVAD was developed to automatically regulate the pump current of the device to avoid ventricular suction. The control system consists of an LSVM suction detector and a feedback controller. The LSVM suction detector is activated first so as to correctly classify the pump status as No Suction (NS) or Suction (S). When the detection is “No Suction”, the feedback controller is activated so as to automatically adjust the pump current in order that the blood flow requirements of the patient’s body at different physiological states are met according to the patient’s activity level. When the detection is “Suction”, the pump current is immediately decreased in order to drive the pump back to a normal No Suction operating condition. The performance of the control system was tested in simulations over a wide range of physiological conditions.
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