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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Development of a Low False-Alarm-Rate Fall-Down Detection System Based on Machine Learning for Senior Health Care

Sui, Yongkun 19 October 2015 (has links)
No description available.
192

PREDICTING RISK FOR ADVERSE OUTCOMES FOLLOWING DISTAL RADIUS FRACTURE

Mehta, Saurabh 04 1900 (has links)
<p>Some individuals remain at risk for adverse outcomes such as chronic wrist/hand pain, falls, and fall-related osteoporotic fractures after distal radius fracture (DRF) remain. This thesis includes five studies that were conducted to establish prediction rules for assessing the risk of these adverse outcomes following DRF.</p> <p>The first manuscript outlines a theoretical framework (RACE - <strong>R</strong>educing pain, <strong>A</strong>ctivating, <strong>C</strong>ognitive reshaping, <strong>E</strong>mpowering) for managing the risk of adverse outcomes, mainly chronic pain, in individuals with DRF. The RACE is one of the first frameworks to suggest a risk-based management approach for individuals with DRF.</p> <p>The Patient-Rated Wrist Evaluation (PRWE) is a condition-specific measure for DRF used in research as well as clinical practice to measure pain and functions in individuals with different wrist/hand injuries. The second manuscript contributes to the literature by providing the first systematic literature review that synthesizes the evidence regarding the psychometric properties of the PRWE. The review determined that the PRWE has excellent reliability, construct validity, and responsiveness in individuals with DRF.</p> <p>The third manuscript indicates that the baseline pain intensity is an independent predictor of chronic pain in individuals with DRF. The results also suggest that the individuals who score ≥35/50 on the pain scale of the PRWE at baseline have 8 times greater risk for developing chronic wrist/hand pain compared to those who score < 35/50.</p> <p>The fourth and fifth manuscripts describe results of a two step study. The fourth manuscript is a structured literature synthesis that identified suitable measures for predicting the risk of falls and fall-related osteoporotic fractures following DRF. The fifth manuscript summarizes the results of preliminary analysis of psychometric properties of selected fall risk measures identified in the fourth manuscript. The fifth manuscript also provides feasibility and sample size requirements for conducting a fall prevention trial in individuals with DRF.</p> / Doctor of Philosophy (PhD)
193

An Obstacle Detection and Fall Prevention System for Elderly People

Emeeshat, Janah Salama 23 May 2022 (has links)
No description available.
194

Using Pollen to Reconstruct Past Vegetation in a Landscape : Comparing Theoretical and Empirical Methods on a Single Pollen Record in Hemavan, Sweden / Användning av pollen för att rekonstruera forna vegetationer : En jämförelse av teoretiska och empiriska metoder på en pollen sekvens från Hemavan, Sverige

Kantak, Johanna January 2022 (has links)
Pollenanalyser har länge gjorts för att få en uppfattning om förflutna vegetationer. Men att återskapa olika miljöer med hjälp av pollen är svårt på grund av en rad olika faktorer. I Hemavan i norra Sverige har ett pollenprov tagits, vilket gör att det går att utforska möjligheterna huruvida det går att rekonstruera vegetationen där eller inte. För att försöka rekonstruera vegetationen kommer två metoder att användas, en kvalitativ beskrivande rekonstruktion samt en som är teoretiskt och baseras på Landscape Reconstruction Algorithm (LRA). Den kvalitativa beskrivande rekonstruktionen resulterade i fyra vegetationskartor under olika skeden från pollenprovet i Hemavan. Den teoretiska rekonstruktionen producerade inga konkreta resultat än hur en hypotetisk vegetationsrekonstruktion kan genomföras med LRA och geografiska informationssystem (GIS). Detta ledde till att det ansågs att den kvalitativa beskrivande rekonstruktionen var bättre lämpad för området i Hemavan, men även att det finns potential att utveckla den teoretiska LRA metoden.
195

In-Situ Geotechnical Characterization of Soft Estuarine Surficial Sediments Using a Portable Free Fall Penetrometer

Kiptoo, Dennis Kipngetich 02 July 2020 (has links)
Knowledge of geotechnical soil properties in the upper meter of the seabed is important for challenges such as scour around submerged structures, management of unexploded ordnances, and generally issues associated with active sediment transport and deposition. Portable free fall penetrometers have been previously used to provide initial information on sediment type, strength, and stratification, but challenges with the calibration of empirical parameters such as the cone factor and strain rate factor hampered the derivation of geotechnical design parameters such as undrained shear strength. This challenge applies particularly in areas of more rare seabed soil conditions such as very soft estuarine sediments. This study aims to advance the analysis procedure of portable free fall penetrometers (PFFP) in soft subaquatic fine-grained soils with natural water contents greater than the liquid limit by estimating the undrained shear strength (su). The logarithmic and power law methods for strain rate correction were investigated at sites in the York River Estuary and yielded a match to vane shear results at a logarithmic multiplier of k=0.1-0.3 and a power law rate exponent of β=0.01-0.03, indicating minimal strain rate effects. Resulting representative cone factors based on sediment strength and profile groupings ranged from 7 to 12 for logarithmic, power law, and no strain correction, and were tested at sites in the Potomac River with similar sediment properties. The PFFP su compared well with mini-vane shear measurements with differences of less than ± 0.5 kPa. Additionally, the PFFP su showed inappreciable differences in strength with or without strain rate application. Therefore, these high water content soils that exhibit little strain rate effects within a soil behavior context, can be better understood through rheological studies. Rheological studies were conducted, and the storage and loss modulus were observed to remain constant when the soil is tested over a range of frequencies. This indicates that the sediment strength is not affected by the rate of soil testing. The outcome of this study is the advanced the use of the PFFP by quantifying the strain rate effects and defining the applicable cone factors for use in estimating the undrained shear strength of soft estuarine marine soils. Furthermore, the understanding of soil behavior of these soils has been explored from rheological context. / Master of Science / Presence of unexploded munitions (UXO) in waterways and coastal environments poses a danger to the populace. UXOs located proud on the seabed can be moved by hydrodynamic forces such as waves and currents to habited areas. This has prompted the need to understand how UXOs interact with the seabed regarding erosion, burial, as well as sinking. Current methods used to detect munitions can lack accuracy from unknown seabed soil conditions. Portable free fall penetrometers (PFFP) are rapid and economical tools that are used to obtain soil information in the seabed. However, the interpretation of the penetrometer data needs to be advanced to get more accurate results of soil strength. In this research, physical soil samples were retrieved and tested in the laboratory. The laboratory results were used to calibrate the PFFP to improve the estimation of soil strength from PFFP. The estuarine soil tested exhibited high water contents raising the question of whether to describe its behavior rather as soil or suspension. Further tests were carried out to study how this soil deforms and flows when a load is applied. The results from this research enable the measuring of strength of the seabed more accurately and improves the understanding of very soft estuarine soil behavior.
196

Preventing slip-induced falls in older adults: perturbation training using a moveable platform and virtual reality

Parijat, Prakriti 24 January 2010 (has links)
Slip-induced fall related injuries are a serious public health issue among older adults leading to considerable mortality, morbidity, and immobility. Existing proactive exercise interventions have produced mixed results on the success of reducing fall accidents. A training intervention may be effective in reducing slip-induced falls, if it can help older adults to practice movements related to recovery responses. The purpose of this study was to evaluate two different training interventions using a moveable platform and virtual reality in order to improve reactive recovery in older adults. Thirty-six older adults were recruited and randomly assigned to three groups (moveable platform training, virtual reality training, and control). The training groups underwent three sessions including baseline slip, training, and transfer of training on a slippery surface. The control group underwent three similar sessions as the training groups, with the training session replaced with a normal walking session. Kinematic, kinetic, and EMG data were collected during all the sessions. The moveable platform training group was repeatedly exposed to simulated slips induced by anterior-posterior movement of a platform. The virtual reality training group was repeatedly exposed to perturbation induced by visual tilts in the virtual environment while walking on the treadmill. Various biomechanical and neuromuscular characteristics were identified to quantify the effects of training. The results indicated a beneficial effect of both training methods in improving recovery reactions in older adults via proactive and reactive adjustments. The reactive adjustments involved faster response to a slip perturbation mediated by reduced time for onset and peak muscle activation (specifically knee flexor), reduced knee and ankle coactivity, reduced time for peak knee, hip, and trunk angles, and angular velocity. The proactive adjustments involved an increased center-of-mass velocity and transitional acceleration of center-of-mass. The overall fall frequency was reduced in the training groups as compared to the control group through improvements in proactive and reactive responses. / Ph. D.
197

A Method for Interpreting the In-Situ Consolidation State of Surficial Seabed Sediments using a Free-Fall Penetrometer

Dorvinen, Jared Ian 13 October 2016 (has links)
Free-fall penetrometers (FFP) are useful instruments for the rapid characterization of seabed sediments. However, the interpretation of FFP data remains largely a skilled task. In order to increase the reliability of results obtained using these instruments, in both expert and non-expert hands, it is advantageous to establish well defined and repeatable procedures for instrument use and data interpretation. The purpose of this research was therefore to develop and refine methods for the interpretation of FFP data. Data were gathered with the FFP Nimrod during two surveys following dredging in Sydney Harbour, Nova Scotia. The challenge of interpreting the data from these two surveys in an efficient and consistent manner was the basis of this work and led to the development of new techniques for improving resolution of the mud-line, identifying areas of erosion and deposition, and qualitatively evaluating the consolidation state of cohesive marine sediments. The method developed for improving the resolution of the mud-line simply describes a procedure of combining the data from different accelerometers with different accuracies and ranges to more clearly define the point of impact with the sea-floor. The method developed to evaluate in-situ sediment consolidation state combines theories of self-weight consolidation and ultimate bearing capacity to predict a range of potential bearing capacities for normally consolidated cohesive sediments. Finally, by combining the previous two methods a third method is proposed for locating areas of potential erosion and deposition. / Master of Science
198

A novel algorithm for human fall detection using height, velocity and position of the subject from depth maps

Nizam, Y., Abdul Jamil, M.M., Mohd, M.N.H., Youseffi, Mansour, Denyer, Morgan C.T. 02 July 2018 (has links)
Yes / Human fall detection systems play an important role in our daily life, because falls are the main obstacle for elderly people to live independently and it is also a major health concern due to aging population. Different approaches are used to develop human fall detection systems for elderly and people with special needs. The three basic approaches include some sort of wearable devices, ambient based devices or non-invasive vision-based devices using live cameras. Most of such systems are either based on wearable or ambient sensor which is very often rejected by users due to the high false alarm and difficulties in carrying them during their daily life activities. This paper proposes a fall detection system based on the height, velocity and position of the subject using depth information from Microsoft Kinect sensor. Classification of human fall from other activities of daily life is accomplished using height and velocity of the subject extracted from the depth information. Finally position of the subject is identified for fall confirmation. From the experimental results, the proposed system was able to achieve an average accuracy of 94.81% with sensitivity of 100% and specificity of 93.33%. / Partly sponsored by Center for Graduate Studies. This work is funded under the project titled “Biomechanics computational modeling using depth maps for improvement on gait analysis”. Universiti Tun Hussein Onn Malaysia for provided lab components and GPPS (Project Vot No. U462) sponsor.
199

Investigation of Pore Pressures During High-Velocity Impact by a Free Fall Penetrometer

Mumtaz, Muhammad Bilal 28 June 2018 (has links)
Free-fall penetrometers (FFPs) are an attractive tool for the rapid characterization of sediments in the nearshore and coastal areas. To improve their measurement capabilities, modern FFPs can be equipped with pore pressure sensors. Pore pressure measurements are extensively used in traditional cone penetration testing, but their usage and interpretation is still limited for FFP testing. This thesis represents an effort to advance the interpretation of pore pressure measurements from FFP testing. Data was collected using the torpedo-shaped FFP BlueDrop during surveys at Herschel Island, YT, Yakutat, AK, Clay Bank, VA, and Yorktown, VA. Additionally, test deployments in the laboratory were performed in kaolin clay. Data analysis was focused on pore pressure measurements during these deployments. Two major advancements regarding current data analysis of FFP pore pressure measurements were explored: 1) a method based on fluid dynamic principles was proposed to correct the pressure recordings for the dynamic flow effects due to the high-velocity fall and impact. The results show that using Bernoulli’s theorem coupled with the concept of pressure coefficients results in good agreement between measured and hydrostatic pressures during the free-fall and initial penetration stage. 2) Pore pressure dissipation curves measured by the penetrometer at rest at maximum penetration depth were also studied. The mechanisms behind the non-standard dissipation curves were explored. The results suggest that non-standard dissipation curves can be interpreted by correcting according to Sully et al.’s (1999) extrapolation technique. The technique can also be used with data from an unsaturated or clogged filter. / Master of Science
200

Fall detection system for elderly using Arduino, Gyroscope and GPS Module

Fitriawan, H., Susanto, Misfa, Santoso, M.R.F., Purwiyanti, S., Hu, Yim Fun, Sigwele, Tshiamo 06 January 2020 (has links)
No

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