In Europe it is approximated that around six million people are active in sport shooting. Currently, most bullets are manufactured out of lead which in many cases is combined with a copper jacket. There are several reasons for using lead; lead is relatively cheap, soft, and has a high density, and is therefore often the ideal material for bullets. Currently, the EU is seeking a restriction or ban on the use of lead in firearm bullets, with the main motivation that hunting with lead bullets might result in lead poisoning of both animals and people. The proposed lead ban will also have a major impact on sport shooting, as it is likely to be subjected to the same regulations. One caliber that has been shown to be very difficult to produce as a lead-free alternative is 22lr (long rifle), which today is the most common caliber for sport shooting in many disciplines. Today, there are not many scientific investigations available which show the performance of lead versus lead-free ammunition in caliber 22lr, even though it would make sense to investigate the possibilities of designing lead-free ammunition before a possible lead ban is further discussed. In this work the performance of two common lead-free 22lr-cartridges is evaluated and shown in comparison with existing lead-based ammunition, with a primary focus on sport shooting. Performance has been evaluated under both summer and winter conditions to cover different sports shooting disciplines. The results of this study clearly show the difficulty of finding lead-free 22lr cartridges with acceptable performance on the market today. In fact, the performance of the tested lead-free ammunition is so poor that the EU's proposed lead ban could completely ruin shooting as a sport due to a lack of functioning ammunition.

A simple and inexpensive corrosion sensor was manufactured to study the corrosion rate of new and water-contaminated lubricating grease using a galvanic cell. A galvanic charge was developed between electroless nickel immersion gold (ENIG) and zinc, manufactured by selectively plating on a custom manufactured interdigitated printed circuit board. This article shows the methodology in using this concept for any application that may require quantifying the corrosivity of a liquid or semisolid that could be applied to the surface of the sensor. Water contamination is a problem in many grease-lubricated machine components, so a sensor concept was developed and a correlation between water content and the corrosion rate is shown. This method could be used to precisely study the corrosion rate of aged or contaminated lubricants and could potentially be used as a cheap and simple way to estimate water contamination in grease. To the best of the authors’ knowledge, this sensor concept has not been used in industry or the literature.

Byggarbetsmiljon i Sverige blir allt viktigare. I takt med hogre tempo, storre konkurrens och komplexaprojekt maste arbetsmiljon prioriteras for att skydda de arbetare som finns ute i landet. Trots ...

Water-contaminated grease samples are investigated with attenuation spectra in the visible and near-infrared (NIR) regions in this article. The purpose of this investigation was to identify a model with optical attenuation spectra such that the water content of grease samples could be characterized with a simple measurement setup using common methodology from the field of instrumental chemistry. The ratio between two chosen wavelengths of light appears to approximate the water content of grease samples with an acceptable coefficient of determination using a methodology to show what can potentially be done to develop condition monitoring tools. To illustrate the outlined method, a prestudy of grease aging and oxidation levels is also investigated to show that other variables do not significantly change the measurement.

The temperature dependence on the dielectric properties of water-contaminated grease is investigated in this article. The purpose of this investigation was to identify the dielectric properties that could be measured to differentiate varying levels of water contamination in calcium sulfonate complex (CaS-X) grease with three different test cells with the purpose of eventually developing a grease condition sensor. Measuring the change in dielectric constant over a small temperature change yielded useful estimations of water content and amount of grease where the added water content ranged from 0.22% to about 5.5%. Additionally, other parameters such as incomplete fill/coverage of the sensors were investigated as a prestudy. The results from this set of experiments show that the measurement has potential to be developed into a condition monitoring sensor in the future.

Recension av Kenneth Lindegren, Osannolika handelser och den svenska realistiska romanen: ett estetiskt och existentiellt bekymmer

Kenneth Lindegren, Osannolika handelser och den svenska realistiska romanen. Ett estetiskt och existentiellt bekymmer. Makadam. Goteborg och Stockholm 2016.

Syfte: Syftet med denna litteraturstudie var att belysa livskvalitet hos personermed KOL och LTOT. Metod: Artikelsokningar gjordes i databaserna CHINAL,MEDLINE och PubMed. 16 artiklar valdes, laste ...

The aim of this case study is to investigate if mergers and acquisition transactions are a value creating activity within engineering consultancy companies before and after the merger and who actually benefits from this activity. The method used for this case study was through qualitative interviews (open-ended & focused interviews), collection of archival records and documents. We began our research by studying different theoretical perspectives presented by numerous researches both historic and present. We searched for different theoretical tools, ways to measure success and failure beyond economic short term profit and also looked into how cultural differences affects the value creation after merging. We looked into hidden motives and what the general opinions are about mergers and acquisitions. Our investigation showed that those who benefited from the merger and acquisition activity were management itself and the shareholders. Those who did not benefit but lost on this activity is the personnel. Our results show that the personnel would have been better off without the acquisition transaction. This explains to some extent the negative and scepticism opinions surrounding this concept.

In aerial vehicle control design, the industrial baseline is to use robust control methods together with gain-scheduling to cover the full airspeed and altitude flight envelope. An adaptive controller could possibly add value by increasing performance while keeping robustness to deviation from nominal assumptions. In this thesis L1 adaptive control is studied and evaluated as it is applied to a pitch-unstable fighter aircraft. The recently developed L1 adaptive control method originates from aerospace adaptive control problems and achieves fast adaptation while robust stability to bounded plant parameter changes is claimed. Even though large adaptation gains create large and rapidly varying internal signals, the L1 adaptive controller output is limited in amplitude and frequency, since a low-pass filter directly at the output, is used to make the controller act within the control channel bandwidth. An L1 adaptive controller of piecewise constant type has been applied to a fighter aircraft by augmenting a baseline linear state feedback controller. Once some experience is gained, it is relatively straightforward to apply this design procedure because only a few controller parameters need tuning. To design an L1-controller for roll-pitch-yaw-motion of an aerial vehicle, a five-state reference system with desired dynamics was created and five bandwidths of low-pass filters were tuned. The L1-controller activates when the vehicle aided by the state feedback controller deviates from the reference dynamics resulting in better reference following. Load disturbance rejection was improved by the L1-controller augmentation. This comes at the cost of having high frequency control signals fed into the plant. The L1 adaptive controller is in its original design sensitive to actuator limitations and to time delays when compared to the baseline controller. Introducing nonlinear design elements corresponding to actuator dynamics (e.g. rate limits) makes tuning easier if such dynamics interfere with the reference system dynamics. Sensitivity to known time delays can be reduced using prediction in a state observer. With these additions to the design, the L1-controller augmentation can be tuned to achieve improved nominal performance and robust performance when compared to a typical aeronautical linear state feedback controller. This was verified by simulations using a high fidelity model of the aircraft. Use of feedforward can alleviate feedback and adaptive actions. Feedforward signals can be generated from reference models and corresponding models can also be used as reference models in adaptive control. A method for aerial vehicle reference model design was developed, that makes it possible to find reference models that scale to the present flight condition and vehicle configuration. In some situations the closed-loop system obtained by L1 adaptive control is equivalent to linear systems. The architectures of these systems were investigated. An effort was made to understand and describe what fundamental characteristic of L1 adaptive controllers make them suitable for aeronautical applications. With the L1-controller, performance and robustness was increased when compared to the baseline controller. It is possible to add L1-controller characteristics gradually to a linear state feedback design, which is something that this thesis recommends to aerospace industry. (Less)

An L1 adaptive controller of piecewise constant type has been applied to a fighter aircraft by augmenting it to a linear state-feedback controller. Angle of attack and sideslip as well as velocity vector roll rate is demanded and controlled. It is relatively easy to design a controller augmentation this way; few parameters need to be tuned. To design an L1-controller for roll/pitch/yaw-motion of an aircraft, a five-state reference system with desired dynamics is created and three bandwidths of low-pass filters are chosen. The L1-controller activates when the aircraft aided by the feedback controller deviates from the reference dynamics. Load disturbance rejection is improved when the L1-controller is active. Results from simulations with different kinds of deviations from the nominal aircraft are presented. Special non-linear design elements need to be introduced if actuator dynamics, including rate limits, interfere with reference system dynamics. Since an L1 adaptive controller of piecewise constant type in its original form is linear time invariant, frequency domain analysis is presented, including comparisons to a typical linear state-feedback controller. (Less)

In some situations the closed-loop system obtained by L1 adaptive control is equivalent to linear systems. The architectures of these systems are investigated and compared with internal model control and the input observer architecture. The analysis is focused on aerospace application. An effort has been made to understand and describe what fundamental control characteristic of flying applications that make L1 adaptive controllers suitable for the task.