Rozprawy doktorskie na temat „Spring wall”

Structural engineers have traditionally detailed structures with structural and fabrication efficiency in mind, but often based on a limited understanding of thermal efficiency. Some connection designs can create significant thermal bridging, leading to unnecessary heat transfer and even premature degradation through condensation. Thermal bridging occurs when heat transfer is given a path through a more conductive material like concrete or steel rather than insulation. Concrete sandwich wall panels (SWP) tend to be highly efficient at preventing heat transfer in the middle of panels, with greatest heat transfer occurring at connections. This project identified thermally efficient details for future SWP construction to reduce heat transfer, lessen environmental impact, and increase sustainability of SWP structures. It can be particularly difficult to avoid thermal bridging at corbel connections, so 12 corbel specimens were created and tested to provide alternative corbel design options for engineers. Nine details were successfully created and are presented. Corbel specimens were modeled using the Beam-Spring Method with good agreement. After validating the Beam-Spring Model, a parametric study investigated effectiveness of the PCI Second Order Analysis and the effect of length, panel stiffness, and wythe configuration on SWP behavior under axial and flexural loads.

Main subject of this work is design of childrens playgroung elements. In this work there is also presented analysis of existent theme. I have designed a few variations, from which I chose the best solution. This solution I worked out in technical, aesthetic and ergonomical aspects. Designed elements match current requirements of safety standards.

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mathematics, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 149-152).
This thesis deals with several combinatorial problems in representation theory. The first part of the thesis studies the combinatorics of affine Springer fibers of type A. In particular, we give an explicit description of irreducible components of Fl[subscript tS] and calculate the relative positions between two components. We also study the lowest two-sided Kazhdan-Lusztig cell and establish a connection with the affine Springer fibers, which is compatible with the affine matrix ball construction algorithm. The results also prove a special case of Lusztig's conjecture. The work in this part include joint work with Pablo Boixeda. In the second part, we define the combinatorial wall-crossing transformation and the generalized column regularization on partitions and prove that a certain composition of these two transformations has the same effect on the one-row partition. This result gives a special situation where column regularization, can be used to understand the complicated Mullineux map, and also proves a special case of Bezrukavnikov's conjecture. Furthermore, we prove a condition under which the two maps are exactly the same, generalizing the work of Bessenrodt, Olsson and Xu. The combinatorial constructions is related to the Iwahori-Hecke algebra and the global crystal basis of the basic [ ... ]-module and we provide several conjectures regarding the q-decomposition numbers and generalizations of results due to Fayers. This part is a joint work with Panagiotis Dimakis and Allen Wang.
by Guangyi Yue.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Mathematics

Background: Current research, surrounding motor laterality at a population level in horses, indicates that in order to stand with the left forelimb in advance of the other, it is achieved by taking a greater amount of steps with the left foreleg than the right foreleg (McGreevy & Thomson 2006; McGreevy et al. 2007); suggesting that pedometers could effectively estimate asymmetry of forelimb locomotion in grazing horses. This novel method of detecting forelimb preference also reduces the likelihood of operator influence and provides an inexpensive objective measure of vertical movement which has the advantage of scoring large sample sizes, avoids single-day anomalies by recording over multiple days and overcomes logistical challenges (Vincent & Sidman 2003; Chan et al. 2005; Silva et al. 2010; Warren-Smith & McGreevy 2010). However in order to determine the reliability and validity of this novel measure the relationship between pedometer data and those derived from direct observation will first need to be assessed (Warren-Smith and McGreevy 2010). Objectives: To determine: (1) if pedometers accurately record equine steps at walk and trot, when compared to video analysis, (2) if alternative positioning of these pedometers affected the accuracy of step detection when compared to video analysis. Method: Five horses each wearing a Yamax Digiwalk SW-200 (spring lever arm pedometer) and a Yamax Power Walker PW-610/611 (piezoelectric pedometer) positioned on the left foreleg (LF), left scapular (LS), chest (C), right scapular (RS) and right foreleg (RF) walked and trotted on a 20m circle 10 times on each rein to yield 100 results for each gait. Video recorded by GoPro Hero 3 Black edition camera positioned on the girth facing the forefeet using the following settings: 180 degree field of view, 720p, 120fps. Both visual and audio data were captured and recorded. Results: Kruskal-Wallis Test on the deviation from actual number of steps per unit for each type of pedometer and the position of the pedometer compared to the actual number of steps taken by both forelegs determined that there is a significant difference (H1= 340.31; P < 0.0001) between readings in walk and also in trot (H1 = 483.49; P < 0.0001). A further Kruskal-Wallis Test on the deviation from actual number of steps per unit for each type of pedometer and the position of the pedometer compared to the actual number of steps taken by individual forelegs determined that there is a significant difference (H = 403.36; p < 0.0001) at walk and also at trot (H = 477.10; p < 0.0001). Conclusion: In summary, the analysis of the pedometer data compared to video analysis indicate that pedometers are not useful for scoring forelimb movements in horses at walk and trot, regardless of positioning.

Ce travail de recherche a pour objectif d’analyser les différentes initiatives de partenariat liant les pays méditerranéens avec l’UE, ainsi que l’élucidation des différents degrés d’engagement et d'implication de ces pays et sous-groupements régionaux dans ces initiatives. Il vise également à dévoiler les différents atouts et faiblesses qui caractérisent les relations Euro-méditerranéennes. La finalité de ce travail de recherche consiste à éclaircir les enjeux de ces relations et la justification de l’utilité de rapprochement entre les pays Sud-méditerranéens avec l’UE dans un espace géographique restreint et dans un cadre historique limité. Ainsi, cette analyse s’est focalisée sur les différents atouts politiques, économiques et sociaux ayant marqué les relations euro-méditerranéennes, durant la période allant de la Chute du Mur de Berlin (1989) jusqu'à l'échec du Printemps Arabe (2013). A l’issue de cette thèse, plusieurs alternatives et pistes de réflexion ont été suggérées, dans la perspective d’éviter les raisons d’échecs déjà constatées et afin de contribuer à l’édification de fondements solides susceptibles de concourir à la réussite des futurs partenariats et initiatives de coopérations euro-méditerranéennes
This thesis is attempting to analyze the various partnership initiatives between the Mediterranean countries and the EU, as well as the different degrees of commitment and involvement of these countries and sub-regional groupings in these initiatives.It also aims at revealing the different strengths and weaknesses that characterize the Euro-Mediterranean relations.The purpose of this research work is to analyze the issues of the Euromed relationships and the size of building links between the Mediterranean countries and the EU in geographically restricted space and during a limited historical period. This analysis has focused on the different political assets, economic and social issues which characterized the Euro-Mediterranean relationships, especially in the period from the fall of the Berlin Wall (1989) until the failure of the Arab Spring (2013). Following this work, several alternatives and ideas have been suggested, with a view to avoiding the failure of stakes already recognized.The objective is to contribute to analysis of creating new strong frameworks which may contribute to the success of the future partnerships and initiatives in relation to the euro- Mediterranean cooperation

Architecture and music share intrinsic meanings generated by a constant stream of metaphors which are forms of poetic transformations. This thesis sought to challenge the present way an architect-musician makes drawings through the exploration of multimedia possibilities at hand. The drawings are composed using Macromedia Flash MX. OPEN HOMEPAGE.EXE To download flash player, click here: Download flash Player
Master of Architecture

This thesis describes the design, manufacture and characterisation of thick vacuum plasma sprayed tungsten (W) coatings on steel substrates. Fusion is a potentially clean, sustainable, energy source in which nuclear energy is generated via the release of internal energy from nuclei. In order to fuse nuclei the Coulomb barrier must be breached - requiring extreme temperatures or pressures – akin to creating a ‘star in a box’. Tungsten is a promising candidate material for future fusion reactors due to a high sputtering threshold and melting temperature. However, the large coefficient of thermal expansion mismatch with reactor structural steels such as the low activation steel Eurofer’97 is a major manufacturing and in-service problem. A vacuum plasma spraying approach for the manufacture of tungsten and tungsten/steel graded coatings has been developed successfully. The use of graded coatings and highly textured 3D interface surfi-sculpt substrates has been investigated to allow the deposition of thick plasma sprayed tungsten coatings on steel substrates. Finite element models have been developed to understand the residual stresses that develop in W/steel systems and made use of experimental measurements of coating thermal history during manufacture and elastic moduli measured by nano-indentation. For both the graded and surfi-sculpt coating, the models have been used to understand the mechanism of residual stress redistribution and relief in comparison with simple W on steel coatings, particularly by consideration of stored strain energy. In the case of surfi-sculpt W coatings, the patterned substrate gave rise to regular stress concentrating features, and allowed 2mm thick W coatings to be produced reproducibly without delamination. Preliminary through thickness residual stress measurements were compared to model predictions and provided tentative evidence of significant W coating stress relief by regulated coating segmentation.

Positioned between writing and drawing, the diagram is proposed by John Berger as an alternative strategy for articulating encounters with landscape. A diagrammatic approach offers a schematic vocabulary that can compress time and offer a spatial reading of information. Situated within the contemporary field of direct data visualisation, my practice-led research interprets Berger’s ‘Field’ essay as a guide to producing four field | studies within a suburban park in Canberra. My seasonal investigations demonstrate how applying the conventions of the pictorial list, dot-distribution map, routing diagram and colour-wheel reveals subtle ecological and biographical narratives.

碩士
國立臺灣大學
機械工程學研究所
106
In this paper we study the deformation and vibration of a pinned-pinned buckled beam constrained by a pair of springy walls of the Winkler type. Small deformation theory is adopted. Static analysis shows that the buckled beam contacts the springy wall in one segment first and then evolves to two-segment contact. In the edge thrust verses end shortening diagram, there exists a maximum edge thrust. The two-segment contact deformations before and after reaching the peak thrust are significantly different. Before reaching the peak, the free-of-contact segment in the middle stays close to the wall. After passing the peak, the free-of-contact segment moves away from the wall until the midpoint touches the opposite wall. In vibration analysis, both load control and displacement control are considered. In load control, the deformation before the edge thrust reaches its maximum is stable, while the one past the peak is unstable. In displacement control, the deformation may remain stable even after passing the maximum thrust. For anti-symmetric vibration modes, the natural frequencies are the same for load and displacement controls. For symmetric modes, the natural frequencies of displacement control are in general higher than the corresponding ones in load control.

Lower body explosive power (LBEP) forms a critical component in any individual and team sport performance and it is therefore essential to develop a means of predicting LBEP in adolescents for early identification of future talent in various sporting codes. LBEP is frequently used by athletes during matches or competitions where explosive movements such as jumping, agility running and sprinting are required for successful performance. These movements are usually found in individual sports such as long jump and high jump as well as in team sports such as basketball, volleyball and soccer. To date not much literature is available on LBEP, especially with regard to LBEP prediction models. Furthermore, studies on adolescents are scarce and a LBEP prediction model has not yet been developed for a South African adolescent population. It is against this background that the objectives of this study were firstly, to develop a LBEP prediction model from various physical and motor performance components among a cohort of adolescents living in the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province, South Africa; and secondly, to develop a LBEP prediction model from several anthropometric measurements among a cohort of male and female adolescents living in the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province, South Africa. Two hundred and fourteen (15.8±0.68 years) 15-year-old adolescents (126 females, 88 males) from 6 surrounding schools within the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province of South Africa were purposefully selected from pre-acquired class lists took part in the study. Data was collected by means of various questionnaires as well as anthropometrical, physical and motor performance tests. For representation of LBEP a principal component factor analysis was done and the results indicated that the vertical jump test (VJT) was the best indicator of LBEP in the cohort of adolescents. With regard to the anthropometrical related LBEP prediction model, the forward stepwise regression analysis yielded a correlation coefficient of R2 = 0.69. The following variables contributed significantly (p≤0.001) to the anthropometrical LBEP prediction model: stature (57%), muscle mass percentage (10%) and maturity age (3%). The LBEP prediction model that was developed equated to LBEP (vertical jump) = -136.30 + 0.84(stature) + 0.7(muscle mass percentage) + 4.6(maturity age). Variables other than the variables that formed part of the study could explain the further 31% variance in the LBEP of the adolescents. The physical and motor performance LBEP prediction model indicated that gender (39%) and 10 m speed (7%) contributed significantly (p ≤ 0.001) to the overall prediction of the LBEP of the adolescents. The LBEP prediction model delivered a stepwise forward regression analysis coefficient of R2=0.458 and a prediction formula LBEP = 68.21 + 9.82 (gender) – 18.33(10 m speed). The remaining 56% of the variance in the results could be explained by other factors than the variables considered in the study. In conclusion, to the best of the researchers’ knowledge, this is the first study which has made an attempt at developing LBEP prediction models from the anthropometrical, physical and motor performance components of a cohort of adolescents of South Africa. The prediction models developed in the study will assist teachers sport scientists and sporting coaches who have limited resources available, to measure and calculate LBEP in adolescents, with the means to do so in South Africa. Further high quality studies are necessary to further improve and develop such prediction models for various age groups of adolescents in the greater South Africa.
MSc (Sport Science), North-West University, Potchefstroom Campus, 2014

碩士
國立臺灣大學
生物環境系統工程學研究所
98
This study using double-layer wall as swine barn design to simulated the sealed swine barn . Use fog spray system inside the wall to cool down the temperature, and add proper Pyroligneous acid into spray system to eliminate the ammonia. This method mainly uses the space inside the wall of the house to improve the environmental operation. The improvement process does not change environment factors such as temperature, humidity and wind speed rapidly, thus maintains better thermal environment managements to provide a cooler and stinkless livestock house environment The effects of cooling ability of spray pressure, operating time and rest time were discussed and the improvement effect is determined by THI(temperature-humidity index); addition to get rid of ammonia, discuss spray pressure, operating time and Pyroligneous acid dilution effect on the ammonia removal effects. Combine of these two strategies and then propose the best spray strategy. The best spray strategy of this facilities is spray pressure 50 kg/cm2, operating time of 25 seconds, rest time of 30 seconds and Pyroligneous acid dilution 100 times. This strategy can cool down the indoor temperature and remove ammonia. Meanwhile, we can provide a more comfortable livestock environment by using THI value as on /off condition.