Mechanochemistry, the use of mechanical stress to activate chemical reactions, has emerged as a significant area of interest in recent years. Two theoretical approaches have been developed to simulate mechanochemical processes: COnstrained Geometries Simulate External Force (COGEF) and External Force is Explicitly Included (EFEI). In the COGEF method, mechanical stress is simulated by increasing the distance between atoms in a molecule that serve as pulling points (PPs) at a constant rate. In the EFEI methods, a constant external force (Fext) is applied between PPs, allowing the atoms to move to maintain that force. Both methods have been used in the literature to study the ring opening of cyclobutene under mechanochemical conditions. These studies have shown that applying a force between cis PPs in cyclobutene induces ring opening along the conrotatory pathway in COGEF-based simulations and ring opening along the disrotatory pathway in EFEI-based simulations. The latter is consistent with experiments. The work in this thesis identifies the origin of the differences in the outcomes obtained with these two methods, which may be of interest in the context of researchers selecting methods to simulate mechanochemical processes. The results demonstrate that the origin of the difference in behaviour is related to the manner in which these methods alter the potential energy surface (PES) through the application of a mechanical stress. Specifically, the PES obtained with the COGEF method does not contain a minimum energy pathway (MEP) linking cyclobutene to the disrotatory product, whereas the EFEI surface does contain such a path. The differences in PESs suggest that the EFEI method is more suitable to simulate mechanochemical processes. The EFEI approach was then used to examine how the electronic structure evolves to permit a formally forbidden disrotatory reaction to occur. The circumvention of the Woodward-Hoffmann rules was not due to a change in the electronic structure. Instead, the application of an external force shifts the transition state along the reaction coordinate towards the reactants, lowering the barrier for the reactions. The orbital effects that disfavor movement from reactants to products are rendered secondary to mechanochemical factors. / Thesis (Master, Chemistry) -- Queen's University, 2011-12-14 16:47:24.197

The emotions associated with initiating, maintaining, and reinforcing hairpulling disorder (trichotillomania) were studied. Studies conducted have only looked at small community or inpatient samples, and little is known about the interplay of hairpulling subtypes and emotions. For this study, 427 participants completed an online questionnaire around their hairpulling subtype, severity, emotions experienced by hairpulling, and comorbid anxiety and depression. Using the Milwaukee Inventory for Subtypes of Trichotillomania-Adult Version (MIST-A; Flessner, Woods, Franklin, Cashin, & Keuthen, 2008), this is the first study to address the regulation of emotions across subtypes. Participants were divided as either high- or low-focused and either high- or low automatic. Significant differences between hairpulling subtypes and hairpulling severity were reported. Subtypes differed in the severity they experienced emotions; individuals with high-focused pulling reported more intense negative emotions, and a greater number of emotions regulated by pulling. Positive emotions⎯happiness, relief, and calm⎯were also found to play a significant role in reinforcing hairpulling. For high-focused subtypes, negative emotions before- and after-pulling were associated with greater severity, indicating that altering negative emotions via pulling plays an important role for high-focused subtypes. High-focused subtypes also reported higher stress, depression and anxiety than either automatic subtypes or the general population, and were found to have anxiety and depression significantly associated with hairpulling severity and experiencing negative emotions that initiated hairpulling. Clinical and treatment implications, study limitations, and areas of future research are discussed / xviii, 227 leaves ; 29 cm

Master of Science / Department of Architectural Engineering and Construction Science / Fred L. Hasler / This paper presents the results of an experiment that was purposed with introducing the physical feasibility of a conceptual product that would mechanically reduce frictional resistance of schedule 40 PVC conduit elbows during the installation of large conductors. In the current construction industry, there is a well established and code driven convention for the construction of PVC conduit. For the installation of building service conductors, significant energy is required to pull conductors through the conduit. The service feed is the most expensive and restrictive pull on most projects strictly due the weight of the large conductors which are heavily resistant to deformation. The forces involved necessitate stringent requirements on maximum pull lengths and maximum degrees bent between pull boxes. Cost and risk of costly installation damage are also major characteristics of service feed pulls. The resistance to pulling and highest concentrations of internal forces throughout any conductor pull is located at the elbows or bends. This study is a scaled experimental-based initial establishment of expected evidence to support the feasibility of a product that would essentially reduce the required force to pull large conductors. This product is idealized as a factory PVC elbow that contains mechanical rollers along the inside face of the elbow where the conductors theoretically make the most contact during pulling. This product will ultimately be more expensive, but would be expected to benefit the project by reducing installation time, possibly reduce the number of pull boxes required, and reduce the risk of damaging conductors or conduits. The experiments described in this paper reflect a small-scale set that establishes trends of varying any one significant parameter for single conductor pulls through a single ninety-degree factory PVC elbow. While further research into multi-conductor feeders must be conducted in order to establish full justification for the product development was expected at the onset, the results of this study show that even further additional research must be conducted to resolve an ambiguity on which a definitive conclusion depends. Due to unforeseen or predicted parameters impacting the reduction of frictional resistance throughout the experimentation, the results both support and counter any benefit of applying mechanical means to reduce frictional resistance. The percentages of reduction range from -37% to +24% across the study’s results. The hypothesized sources of the ambiguity that counter expectations can only be verified by future studies. However, the evidence from this study can become definitively directional for the pursuit or lack there of for further investigating the benefits of the idealized product.

The spread of wireless devices inspired the creation of a DEECo component model suitable for designing applications with immanent mobility and dynamic composition where the system architecture emerges at runtime. A great challenge in implementation of such a system is the underlying communication mechanism based on gossip protocol in order to achieve resilience and suitability for MANET networks. In this thesis we propose an optimization of the protocol exploiting infrastructure networks, but still preserving the gossip-like communication without a centralized element. The improvement is based on forming communication groups introduced at the design level. The experiments show a substantial decrease in the number of sent messages and a decrease in time of data delivery. The timing aspect of data delivery is further elaborated for MANET networks by implementing a pulling mechanism with significant improvement of the latency. Part of this thesis is dedicated to a formal specification of the system semantic to provide a precise rationale about its properties and laying the ground for further extensions and research. Powered by TCPDF (www.tcpdf.org)

Fifteen adult women (mean age 34.5 years) participated in this exploratory study. The study aimed to identify commonalities in trichotillomania patients’ personality structure and psychological functioning. Relevant historical data were obtained, the Massachusetts General Hospital Hairpulling Scale was completed, and a Rorschach test in terms of the Comprehensive System was administered. The results point to an innate vulnerability in the sample’s personality structure that impedes their capacity for efficient problem-solving, decision-making, and coping behaviour. Other key findings include a distorted perception of themselves, a limited capacity for control and stress tolerance, difficulty in modulating and expressing emotions, the interference of primary process thinking in ideational activity, and the effects of these factors on their interpersonal relationships. Theoretical inferences are made about the probable aetiological roots of these findings. As the subjects’ level of functioning was unexpectedly high in the light of their deep-rooted pathology, the dynamic role and function of self-induced hair pulling as a symptom were considered. Suggestions are made to improve the treatment prognosis of the disorder. / Dissertation (MA (Clinical Psychology))--University of Pretoria, 2006. / Psychology / unrestricted

abstract: At least 30 datacenters either broke ground or hit the planning stages around the United States over the past two years. On such technically complex projects, Mechanical, Electrical and Plumbing (MEP) systems make up a huge portion of the construction work which makes data center market very promising for MEP subcontractors in the next years. However, specialized subcontractors such as electrical subcontractors are struggling to keep crews motivated. Due to the hard work involved in the construction industry, it is not appealing for young workers. According to The Center for Construction Research and Training, the percentages of workers aged between 16 to 19 years decreased by 67%, 20 to 24 years decreased by 49% and 25 to 34 age decreased by 32% from 1985 to 2015. Furthermore, the construction industry has been lagging other industries in combatting its decline in productivity. Electrical activities, especially cable pulling, are some of the most physically unsafe, tedious, and labor-intensive electrical process on data center projects. The motivation of this research is the need to take a closer look at how this process is being done and find improvement opportunities. This thesis focuses on one potential restructuring of the cable pulling and termination process; the goal of this restructuring is optimization for automation. Through process mapping, this thesis presents a proposed cable pulling and termination process that utilizes automation to make use of the best abilities of human and robots/machines. It will also provide a methodology for process improvement that is applicable to the electrical scope of work as well as that of other construction trades. / Dissertation/Thesis / Masters Thesis Construction Management 2020

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My dissertation describes the procedure and results of designing a single-purpose machine, which is designed for forming a stainless metal product from an initial semi-finished product. This semi-finished product is a 0.28mm-thick stainless-steel plate. The introduction of my dissertation outlines the evolution of the pulling technology in the Czech Republic and abroad and describes its further details. This research part also includes an overview of individual machines according to the CSN. The practical part is then further dedicated to the exploration of individual issues and requirements for designing the machine itself as well as designing the machine according to the requirements of the final pulled product.

The thesis summarizes the results of the measurement of the output parameters of the tractor, on which were mounted three different types of tires. The measured parameters are the maximum pulling power, slippage, specific effective fuel consumption at the maximum pulling performance. The final measured and calculated results are presented in tables and graphs. The results of the measurements were processed by the use of regressive analysis.

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