Hydro power plants are an essential part of the infrastructure in Sweden as they stand for a large amount of the produced electricity and are used to regulate supply and demand on the electricity grid. Other renewable energy sources, such as wind and solar power, have become more popular as they contribute to a fossil free society. However, wind and solar power are intermittent energy sources causing the demand for regulating power on the grid to increase. Hydro power turbines are designed to operate at a certain design point with a specific flow rate. The plants are operated away from the design point when used to regulate the supply and demand of electricity. This can cause a specific flow phenomenon to arise in the draft tube at part load conditions called a Rotating Vortex Rope (RVR) which causes dangerous pressure fluctuation able to damage blades and bearings. A solution to mitigate a RVR is to inject pulsating momentum into the draft tube by using an actuator operating at a certain frequency. A literature study was conducted and three techniques were numerically simulated using ANSYS Workbench 19.0 R3; a fluidic oscillator, a piston actuator and a synthetic jet actuator. A dynamic mesh was used to simulate the movement of the piston actuator and diaphragm of the synthetic actuator whilst the mesh of the fluidic oscillator was stationary. The relative errors of the three numerical models were all below 3 %. All devices showed promising results and could potentially be used to mitigate a RVR because they all have the ability to produce high energy jets. The fluidic oscillator had an external supply of water, whereas the other two did not, which means that it could inject the largest mass flow. The piston actuator required a driving motor to move the piston. The diaphragm of the synthetic jet actuator was moved by a Piezoelectric element. Advantages of the fluidic oscillator are that it has no moving parts, in contrary to the two other devices, it can directly be connected to the penstock or draft tube to obtain the required water supply and it is easy to install. It will most likely also be smaller compared to the other two for the same mass flow rate. It does however not generate a pulsating jet, but rather an oscillating jet. The other two devices generate pulsating jets, but have problems with low pressure areas during the intake stroke which can cause cavitation problems. These areas cause the formation of vortex rings close to the outlet. Simulations showed that a coned piston together with a coned cylinder outlet could decrease losses by almost 16 % compared to a normal piston and cylinder. It also decreased the risk for cavitation and the required force to move the piston. Otherwise, a shorter stroke length for a constant cylinder diameter or a longer stroke length for a constant volume displacement also decreased the risk for cavitation and required force. The gasket between the piston and cylinder is a potential risk for leakage. A solution to avoid critical low pressure areas is to install an auxiliary fluid inlet or valve which opens at a certain pressure for the piston actuator as well as the synthetic jet actuator. This will also allow larger mass flow rates and a higher injected momentum. Both devices are more complicated to install and require likely more maintenance compared to the fluidic oscillator. However, there exist many possible design options for the piston actuator. The design of the synthetic jet is more limited because of the diaphragm. The amplitude of the diaphragm also has a direct effect on the pressure levels. The losses increased proportional to the mass flow to the power of three which suggests that it is better to install many small actuators instead of a few large ones.

Die Arbeit befasst sich mit der Untersuchung des Reibwertes zwischen Seil und Seilrille, von hochfesten synthetischen Faserseilen, in Treibscheibensystemen. Im Grundlagenteil werden Aufbau, Funktion und Berechnung derartiger Fördersysteme nach dem Stand der Technik dargestellt. In den letzten Jahren haben als Zugmittel verstärkt Seile auf Basis hochfester, synthetischer Fasern Einzug gehalten. Diese Seile sind deutlich leichter als die bekannten Drahtseile und weisen dabei zum Teil höhere Festigkeitswerte auf. Um solche hochfesten Seile gezielt in fördertechnischen Anlagen einsetzen zu können, ist es erforderlich, diese Seile grundlegenden Untersuchungen zu unterziehen. Geprüft wird dabei z.B. auch die Treibfähigkeit. Der Wissenstand auf diesem Gebiet kann im Vergleich zu den Drahtseilen als mangelhaft angesehen werden. Um eine ausreichende Treibfähigkeit (u.a. eine Funktion des Reibwertes) zu gewährleisten, ist es notwendig die Reibwerte in Abhängigkeit des Verschleißzustandes des Seils und der Seilscheiben zu ermitteln und zu analysieren. Bei diesen Untersuchungen werden Parameter wie der Seilwerkstoff, die Rillengeometrie und die Drehzahl der Treibscheibe oder die Vorlast variiert. Ziel der Untersuchungen ist die Ermittlung vorteilhafter Kombinationen von Seil und Scheibe in Bezug auf die Treibfähigkeit. Abschließend erfolgt die kurze Darstellung einer neuen Berechnungsmethodik, welche den Stand der Technik um die Besonderheiten der Faserseile erweitert. Damit lassen sich neue Anwendungsfelder generieren. / During the last years, high-strength synthetic fibre ropes have found there ways into the sector of tension members and traction mechanisms. These ropes are significant lighter than known steel wire ropes and, beside this, do show a higher strength. For using such ropes pointedly in conveyors and conveying systems, basic research has to be done on the ropes. The behaviour in cyclic bending, the creep behaviour and wear mechanisms are to be examined. The knowledge on these fields is, compared to the knowledge on steel wire ropes, insufficient. A study on the friction coefficient of high-strength synthetic fibre ropes working on drive sheaves are to be presented within this paper. To ensure an adequate drive capability (which is a function of the coefficient of friction and the wrap-around angle), it is necessary to investigate and analyse the coefficients of friction in dependency of the state of wear. During the investigations, parameters like groove dimension, number of revolutions per minute and initial load have been varied. Target of the investigations is, to evaluate an optimised combination of rope and drive sheave in terms of drive capability. Appropriate applications in conveying engineering can be derived from this optimised combination.

This article presents theoretical and empirical insights into how Ljubljana is integrated into the discourse of a creative city through top-down discourses and practices, and how bottom-up activists and stakeholders actively position themselves towards this development. The phenomenon described is an example for the realization of European cultural policy in a local context on the geopolitical and imaginative periphery of “EU-rope”: Slovenia.

There is a link between the tactile and optical modes of perception. Woven textiles’ materiality and ability to take three dimensional form, make them a good medium for creating shapes containing several pattern scales and textures. By conciously working with tactile-visual qualities and aesthetics one can achieve the most powerful effects, and in turn, the textile can take the role of a sensation director. By interpreting Kasuri with large scaled threads on a computerized hand loom and in space, an exploration of details and spatial installation can be conducted simultaneously. The five examples developed in this project demonstrate different approaches to dimensional hand weaving, intending to build a better understanding of micro and macro spatial features in woven textiles. Significantly, the project challenges the scale of hand weaving as well as the design process: stretching from thread to dimensional weave empowers the designer. By highlighting crafted details on a large scale, a sequence of events can be discerned that makes the spectator aware of quality and of the production process. Parallels between the body of work and our perception of lines and interspaces are drawn as an attempt to refine our relation to the objects around us.

The artistic research, Kehrä/ Kehrae is done together with Myrsky Rönkä, with significant ropes, places and spaces, creatures and histories. This paper is subtitled entwining possible worlds. It implies alternative possibilities for prevailing modern western ways to live and die and circus. There are three big questions in the air: What is the meaning of circus? What does it mean to be alive? And how could circus care (the existence of life within the earth)? The starting point was a concern about the troubling state of life and the world how it is today and how the modern western circus felt paradoxical and incapable of responding to the current times in sustainable ways. The initial question was, how to combine circus and other aspects of life into one sustainable, or regenerative and renewable practice. In order to seek other, latent realities this research goes beyond modern western circus history, beyond modern western worldview, and beyond “ordinary” circus practice.  The guiding idea is: life is circus, circus is life. Therefore the practice in this research is a collection of “whatever we were doing”. To mention some with great importance: whirling, meditation, becoming-with rope, making and mapping space with ropes and strings, dwelling with nature, and sauna. The other idea is to go through liminality and evoke communitas, with circus practice, bodies, ropes, and others.  This means abandoning accustomed ways to train and think about circus and life. Because of its nature, this work is also opening up what could spiritual (circus) practice mean as an alternative to a mechanistic way of thinking and making. The ontology of this research is animistic and relational, which suggests care, respect, reciprocity, and response-ability in all of our relations and takes into account the circulative nature of time and life. Animistic ontology takes materiality and skill towards the idea of becoming-with, when becoming into who and what happens in relational material-semiotic worlding. During the process, some specific features, or dwelling places for circus, emerged. Those are circus and play, circus and liminality, circus and shamanism, circus and others. In these dwelling places lies the deep powers of circus to be inversive and subversive, simultaneously transformative and sustaining: the mythical power of circus. Through the final artistic outcome Kehrä/ Kehrae, this paper is entwining the strings of the research together as a temporary gathering to be unraveled and intertwined into one again.

First of all, my research is not only my research but our research. It has been made together with my long-time art companion Marjut Hernesniemi. The starting point for our research was our experience of the western modern circus, what it does, and how it cares for the cosmos. From our experience, the western modern circus is based on techniques, risk, danger, and spectacle. Human is in the center of it, often presented as superhuman controlling and manipulating everything. By looking at the current situation in the world, human domination has caused us problems in a form of climate change and other ecological crises such as mass extinction. However, there are different ways of relating to the world. In this research we have looked beyond the western modern circus, to the roots of circus in China and Japan, and to the archaic rituals, to find other ways of relating to the world through circus and trying to bring them to the present day. This research was set out with the question of trying to combine circus and other aspects of life as one sustainable or regenerative practice. The theoretical framework of the research has been ritual. The thought behind that has been the efficacy of the ritual in contrast to entertainment. That is circus can make a difference. From an animistic perspective, the purpose of the ritual is to sustain and renew, preserve or bring back the balance between the psyche, body, social, cosmic, and circle of life. With this in mind, we have made use of the anti-structure of liminality as a playground while working in the studio. In this playground, we have not been bound by the custom, convention, or ceremonials of the western modern circus. Instead, we’ve had the possibility to play. Use the definition of western modern circus as a launching pad and try to run as far as possible, but still have the connection point as the one that we left from. The rules of the play were simple, such as we don’t climb the rope, you are not allowed to hurt the rope, instead of objects, materials of becoming, instead of human exceptionalism, appreciation of the other, what if there was no human on stage. All these rules created different possibilities.  While in liminality we have been bound by another thing that can appear in a liminal phase, communitas. Communitas as an unstructured communion of equal individuals working towards a collective task with full attention. In our communitas, the task has been a sustainable circus. Moreover, in our communitas, ropes and nature were included as equals. Together we have been imagining and making different kinds of possible futures. These relations between us, nature, and the ropes have been intimate relations. During the process of making, humans have been ”affected” as much as the significant other.  Our task was to combine circus and other aspects of life as one sustainable or regenerative practice. As performances in circus consist of ritualized gestures that show the relationship between us and the cosmos, we need to rethink what we are presenting. To find a more sustainable and regenerative future, we need collective survival skills instead of individual ones. These survival skills should include all life in its diversity. For change to happen liminality, communitas and play are all needed. Liminality to open up a playground outside of the structured society. Play to come up with solutions to challenges. Communitas to form a special bond between the players, speak for the weak, and not forget that we work for the same cause.  Circus can transform, however it requires that the artists are willing to go through the liminal space themselves and take circus with them.

Tittle: Description quadrupedal locomotion diagonal pattern in specific sport activity (rope climbing, walking, pull-up) Aim of work: The aim is to find a description kvadrupedal locomotion diagonal pattern with rope climbing and its motion pattern compared with the motion pattern of walking and pull-up. Methods: This work is descriptively-association study with quantitative and qualitative analysis. The dates were measured by surface electromyography and 2-D video-analysis. Results: Alternating activation of upper extremities (rope climbing without the lower extremities), we proved that the movement supporting lower extremities is quadruped locomotion diagonal pattern. Symmetric work of upper extremities (pull-up) is not in response at lower extremities quadruped locomotion diagonal pattern. Key words: Electromyography (EMG), quadruped, diagonal pattern, rope climbing, pull-up, walking

The use of renewable energy such as water and wind to produce electricity has been proven extremely effective in Sweden. The ability of these renewable resources to produce clean output energy counters the adversities caused by non-renewable resources. The use of hydraulic turbines is a good example of favoured technique for energy and power production using renewable resources. The hydro-turbines are designed to operate at best efficiency point (BEP). Varying energy demands in recent years implies on the need of flexible operation of hydraulic turbines. The issue of pressure pulsations in the draft tube of hydro-turbines, observed at lower operating conditions has been unresolved for many years. These pressure pulsations are related to the ‘rotating vortex rope’ (RVR) observed at part load operation and, affects the lifespan and performance of the hydro-turbine adversely. Several techniques have been investigated in the past to reduce the pressure pulsations in the draft tube at part load operation and enhance the flexibility of the turbine. During the present research study, a passive flow control technique was investigated numerically by implementing a guide vane system in the draft tube of the Francis-99model turbine. Guide vanes are mechanical devices that can direct the flow in a desired direction. The current study presents the possibility of reducing the pressure pulsations in the draft tube by mitigating the RVR using a guide vane system in the draft tube. At the initial stages of the research study, a reduced numerical model of the Francis model turbine was developed by only considering the draft tube domain. The motive was to develop a reduced model to perform the parametric analysis for the guide vane system in the draft tube with reduced computational time, power, and storage. The results obtained from the numerical study were found to be in good agreement with theFrancis-99 semi-model with passage domains. A parametric study was performed to achieve a guide vane system design that could mitigate RVR with minimum losses. During this study, the number of guide vanes, the chord and the span of the guide vanes were investigated. It was found that a set of three guide vane system with chord of 86% of runner radius and leading-edge span of 30% of runner radius is an ideal design that mitigates RVR above 95%.

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This dissertation reframes the history eighteenth-century British art as a history of textiles. Women across England, Ireland, and Scotland grew, dressed, spun, and wove the hemp, flax, and wool textiles that were the basis for both the cultural implements and practical tools of empire: oil paintings on linen canvas and needlework of worsted thread hung in metropolitan exhibition spaces, while hemp rope, sail cloth, and coarse linen facilitated Britain’s global reach and transportation of commodities. Over the course of three chapters, “Rope,” “Linen,” and “Thread,” I demonstrate how ordinary textiles made and used by women were key tools for the funding, making, and aesthetics of art. In the first chapter, “Rope,” I trace the labor of female models in British drawing academies through their poses supported by rope, and consider historical encounters between rope and the female working body in carceral contexts. Following the entwined forms of life models and rope demonstrates just how entangled the spaces of punishment and the life studio were. The second chapter, “Linen,” is about the structure, materiality and hidden histories embedded in linen painting canvas. First, by comparing linen weaves, thread counts, stamps, and fiber content, I demonstrate the material connections between the world of coarse linen goods and the textile supports of oil paintings. I then argue that the texture of canvas was crucial to the “unfinished” aesthetic of portraiture that became fashionable in the late eighteenth century and attend to the racialized and gendered discourses intrinsic to this painting style. The last chapter, “Thread,” examines spinning and needlework as elite performances of female industry against the backdrop of mechanization, nascent labor movements, and imperial expansion. I contend that these conflicts played out in romanticized depictions of women spinning and the celebration of public exhibitions of worsted embroidery, namely Mary Linwood’s Gallery. While scholars from the fields of economic history, material culture, and art history have considered the topics of industrialization, labor, textiles, and art separately, this is the first study to bring them together as an intervention in eighteenth-century British art history. By rendering textile labor visible in eighteenth-century British art, I argue that manufacturing, imperialism and the visual arts were financially, materially, and ideologically enmeshed processes.