The potential gains that could be realized from optimizing timber harvesting are significant. To a great extent it is these initial functions that dictate the quality of future manufacturing steps. Timber harvesting systems are defined by the operations they contain and the equipment that perform them. For any given harvesting situation there are a large number of unique systems, performing under a variety of cost, production, and environmental conditions. The objective of optimized timber harvesting is to reduce cost while simultaneously increasing production and minimizing environmental impact. One way to accomplish this objective is through mechanization and automation. Mechanization increases the production output, efficiency, and product quality. However selecting an appropriate level of mechanization to avoid under utilization of expensive resources is a critical decision. The decision requires that the product mix, environmental and user specified constraints be matched against the available equipment technology, and the required performance criteria. This research describes a computer based system which queries a user on the timber stand specifics and a set of harvesting objectives. The system then matches these user's needs to a level of mechanization that would maximize the efficiency of the production system. The computer accomplishes this by searching a set of databases containing information on the available technology and its impact on production, efficiency, economics and the environment. The level of mechanization is determined by specific combinations of existing equipment. Individual pieces of equipment that are compatible with one another are balanced together to form a viable productive unit. / Graduation date: 1991

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Thesis (M.S.)--Case Western Reserve University, 2010. / [School of Medicine] Department of Biomedical Engineering. Includes bibliographical references.

Thesis (M.S. in Operations Research)--Naval Postgraduate School, June 2004. / Thesis advisor(s): Thomas Lucas. Includes bibliographical references (p. 89-91). Also available online.

Thesis (M.S. in Electrical Engineering and M.S. in Modeling, Virtual Environments and Simulation)--Naval Postgraduate School, September 2003. / Thesis advisor(s): Xiaoping Yun, Fotis Papoulias, Joseph Sullivan. Includes bibliographical references (p. 89-90). Also available online.

Thesis--M. Sc., University of Hong Kong, 1982.

Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Ludovice, Pete; Committee Member: Chen, Rachel; Committee Member: Harvey, Steve; Committee Member: Sambanis, Athanassios; Committee Member: Wartell, Roger. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Hand motion analysis methods have been providing researchers with motion investigation initiatives, revealing motion features and mechanisms in both healthy subjects and patients suffering from hand dysfunctions. Technical advancements have led to the maturation of motion capturing methods such as goniometric gloves. In this project, the CyberGlove as a manufactured product was chosen as a potential tool for the development of a hand function assessment system that would ultimately distinguish between healthy subjects and patients suffering from hand dysfunctions. In this study, the evaluation of the CyberGlove as a feasible clinical tool and its technical adaptations were done in parallel. The sensor output characteristics were investigated using X-ray photography as a spatial golden standard and the sensors were shown to exhibit linear qualities with optimal nonlinearities at 0.6%. The measurement sensitivity and accuracy by the CyberGlove was improved by establishing a calibration protocol suiting the sensor characteristics. Through a calibration protocol using calibration tools made by thermoplastics, the angular measurement error was found to decrease from 7.2% to 1.2%. The technical development of the software part of the project involved the inclusion of data preprocessing, display and analysis modules. To investigate the motion exhibited by healthy subjects, 32 healthy subjects were recruited and they were asked to complete a series of motion according to a designed motion protocol involving a static trial, a timed-grip trial and a rapid-grip trial. Motion features were extracted from recorded motion data by identification and quantification of temporal or spatial characteristics in motion such as joint sequence of events, angular kinematics, finger tip path features and phase diagram features. Some features were evaluated by pattern correlation analysis by linear regression, and healthy subjects all shared similar patterns resulting in high levels of regression coefficients R2 and low levels of slope deviations m. The establishment of motion features along with a prototype motion measurement system allows the continuous development on the CyberGlove as a hand function assessment tool when supported by later clinical adaptations or studies. / published_or_final_version / Orthopaedics and Traumatology / Master / Master of Philosophy

Crystal plasticity has been an active research field for several decades. The crystal plasticity of the bulk materials has its key relevance in the industrial process. Besides, the plasticity of nano-sized materials becomes a topic attracting a lot of interest recently. In the Part I of the thesis, molecular dynamics (MD) simulations were used to study the plasticity of small nanoparticles. Firstly, the coalescence process of Cu nanoparticles was explored. It was found that a peculiar type of five-fold twins in the sintered products were formed via an unseen before dislocation-free process involving a series of shear waves and rigid-body rotations. Secondly, a similar study on the heating of a single nanoparticle was conducted. The same dislocation-free shear wave mechanism was spotted again. In this mechanism, a cluster of atoms rearranges in a highly coordinated way between different geometrical configurations (e.g. fcc, decahedral, icosahedral) without involving dislocations. Thirdly, simulations on the sintering of many nanoparticles were performed, and the governing processes during the consolidation were discussed. The findings in this part of the thesis can provide some guidance for controlling the motifs of nanoparticles. In Part II of the thesis, the emphasis was switched to the crystal plasticity at larger spatial and temporal scales. A dislocation density-based model was developed in our research group. This model employs a dynamics formulation in which the force on each group of dislocation density is calculated with the Taylor and mutual elastic interactions taken into account. The motion of the dislocation densities is then predicted using a conservative law, with annihilation and generation considered. The new dislocation density-based model was used in this work to simulate the plastic deformation of single crystals under ultrasonic irradiation. Softening during vibrations as well as enhanced cell formation was predicted. This is the first simulation effort to successfully predict the cell formation phenomenon under vibratory loadings. / published_or_final_version / Mechanical Engineering / Master / Master of Philosophy

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