This master's thesis makes a brief comparison of design variants of cranes for general use on the deck of a vessel. Further, this thesis deals with a design of a crane with a telescopic jib and a single knuckle. An important part of the crane’s design is its kinematic solution, which was modified in the design phase. The last step of a simplified analytical calculation of the jib for design steel construction is given. This preliminary calculation is the starting point for a FEM model and for the following FEM analysis. A stress control is made according to the Lloyd's Register of Shipping agency’s standard for lifting appliances in marine environment and also according to the recommendations of Huisman company. A part of the proposed solution is a selection of main components of the crane. The master’s thesis contains a summary of some operational and other information which characterize possibilities of the crane’s use. This thesis also includes source materials for drawing documentation.

Thin films have become very important in the past years as there is a tremendous increase in the need for small-scale devices. Thin films are preferred because of their electrical, mechanical, chemical, and other unique properties. They are often used for coatings, and in the fabrication of Microelectronic devices and Micro-electro Mechanical Systems (MEMS). Internal (residual) stress always exists when a thin film is employed in the device design. Residual and thermal stresses cause membrane bow, altering the anticipated dynamic response of a membrane-based MEMS design. The device may even become inoperable under the high stresses conditions. As a result, the stresses that act upon the membrane should be minimized for optimum operation of a MEMS device. In this research, the fabrication process parameters leading to low stress silicon nitride films were investigated. Silicon nitride was deposited using Plasma Enhanced Chemical Vapor Deposition (PECVD) and the residual stresses on these films were determined using a wafer curvature technique. By adjusting the silane (SiH4) and nitrogen (N2) gas flow rates, and the radiofrequency (RF) power; high quality silicon nitride films with residual stress as low as 11 MPa were obtained. Furthermore, an analytical study was also conducted to explore the effect of thermal stresses between layers of thin films on the MEMS device operation. In this thesis, we concentrated our efforts on three layers of thin films, as that is the most commonly encountered in a membrane based MEMS device. The results obtained from a parametric study of the membrane center deflection indicate that the deflection can be minimized by the appropriate choice of materials used. In addition, our results indicate that thin films with similar coefficient of thermal expansion should be employed in the design to minimize the deflection of the membrane, leading to anticipated device operation and increased yield. A complete understanding of the thermal and residual stress in MEMS structures can improve survival rate during fabrication, thereby increasing yield and ultimately reducing the device cost. In addition, reliability, durability, and overall performance of membrane-based structures are improved when substrate curvature and membrane deflection caused by stresses are kept at a minimum.

In the field of Cybersecurity, it is essential to know who is connected to your system. The functionality for Authentication of connecting users in the local area network is in the focus for this report. There exist various authentication protocols, however in this report IEEE 802.1X is covered since it is the protocol most suitable for wired local area networks. The IEEE 802.1X protocol is studied in theory with its architecture of Supplicator, Authenticator and Authentication server and the used communication protocols EAPOL and RADIUS. A practical test was then performed as a basic concept to learn more about pros and cons for utilizing these protocols where the fundamentals of protocol communications are observed and later the prerequisites for a larger scale implementation are described.  The outcome from the test is proof of the relative difficulties involved with having to keep up with the pace of Cybersecurity evolution. In the test, older equipment where thought to be used, however due to incompatibility of gear and software the test needed to be revised to use other gear. The learning outcome from the test is that it is a complex task to set up authentication, competent staff are needed, as well as suitable equipment.  The motivation for setting up IEEE 802.1X is found in larger organizations where the risks of an attack are high, the large number of users calls for centralized systems for the handling of users and network policies. Due to the trend of Bringing you own device, a policy for the handling of unauthorized users and devices is needed to be in place. The default behavior may be to just deny access for unauthorized devices, however with authentication systems implemented the unauthorized user may instead benefit from being automatically referred to a guest network in a secured manner and the authorized user gains flexibility to access the network thru any available network port.  For the improvement and maintenance of Cybersecurity administration an Information Security Management System is found useful, the organization can thereby continuously improve their work and document the system features and routines. In case of a security breach that system gives support for immediate action upon the problem, and even stronger preparation for the Cyber defense in the form of good backup routines and monitoring the normal state activities where all devices are either authorized or unauthorized and placed into their proper network according to network policies. / <p>Examensarbete för högskoleingenjörsexamen i nätverksteknik</p>

Dagens företag vill ge anställda möjlighet att jobba hemifrån eller på resande fot. En vanlig lösning för att möjliggöra detta är virtual private network (VPN). VPN ger en användare tillgång till interna resurser på företaget från ett externt nät, exempelvis via Internet. Detta gör att användare kan komma åt de interna resurserna på ett säkert sätt. Vilken VPN-teknik är då att föredra för att få en så snabb, säker och pålitlig anslutning som möjligt? Detta examensarbete tar upp olika VPN-tekniker. Vi beskriver vanliga VPN-protokoll som L2TP, IPSec och PPTP. Hur användare autentiseras på ett säkert och smidigt sätt samt metoder att göra sin VPN-anslutning säker. Vi redovisar också den lösning vi har implementerat hos Confidence, för vilka arbetet utfördes. Problemen med att använda de produkter som redan fanns på företaget beskrivs. Förslag på lösningar ges för att lösa dessa problem i framtida arbeten. / Companies of today want to give their employees the opportunity to work from home or while they travel. A common solution to accomplish this is to implement a VPN over top of the existing network. Using VPN gives the employees access to the company’s local area network from outside, via the internet. The VPN provides a secure channel for these employees to connect to the local services attached to the company’s network that they need to reach. Which VPN technology is most suitable to deliver a secure, fast, and reliable connection to theses employees? In this thesis examines we are taking a closer look at different VPN solutions. We describe different VPN-protocols like L2TP, IPSec and PPTP. How to authenticate users in a secure and flexible way and also methods used to make the VPN-connection secure. Lastly we will show the solution we have implemented at the company Confidence, for whom we made the solution. The difficulties in using existing products with the company’s infrastructure are described. Suggestions are offered for future work to address these problems.

Authentication, authorization, and accounting (AAA) are key elements in network security. In many networks, clients can use resources only after they have been authenticated by an authentication server and authorized to use these resources. In some cases the server will also maintain accounting records in order for an operator (a provider of resources) to charge the account/subscriber for using the service. There are four main AAA protocols being used today. Of these RADIUS is the mostly widely used. This thesis starts with an introduction to AAA protocols, and then goes in the details of RADIUS. In order to perform a practical evaluation of how the AAA could be improved, FreeRADIUS was selected as the base code for this project; because this implementation is one of the most widely used RADIUS servers. A proposal for how to improve AAA performance is introduced and the implementation steps needed to realize these improvements are shown. Additionally, some experiments have been conducted to show both the correct functioning of the resulting implementation and to examine if there is a performance improvement. Following this some conclusions are drawn based upon a comparison with a traditional AAA server. A key element of the change in AAA which is proposed is the use of a non-binary IEEE 802.1x process. This new non-binary solution introduces a new type of AAA server and requires the re-thinking of a number of traditional AAA design decisions. It is expected that this change will have a significant impact, but will require some time for exposure, implementation by others, and a more extensive evaluation that was possible during the period of this thesis project. One of the most important conclusions drawn during this thesis is the difficulty of making a change in authentication and authorization, because of the large amount of interaction between both the various protocols and the standards which have been developed for these protocols. Thus one of the difficult aspects of the task is how to introduce a change in a protocol while maintaining backward compatibility for others who have not adopted this change -- without requiring the addition of a protocol version field. A second important conclusion is that doing this implementation in three separate parts with different students being responsible for the different parts revealed just how complex the interaction of protocol design decisions are. While a working version of the entire set of changes proved to be impossible, it was observed that the different parts could be decoupled more than initially expected.

Dokument enthält auch die nachfolgende Diskussion.

We perform high precision measurements of an isotope shift between the two stable isotopes of helium. We use laser excitation of the 2^3 S_1-2^3 P_0 transition at 1083 nm in a metastable beam of 3He and 4He atoms. A newly developed tunable laser frequency selector along with our previous electro-optic frequency modulation technique provides extremely reliable, adaptable, and precise frequency and intensity control. The intensity control contributes negligibly to overall experimental uncertainty by stabilizing the intensity of the required sideband and eliminating the unwanted frequencies generated during the modulation of 1083 nm laser carrier frequency. The selection technique uses a MEMS based fiber switch and several temperature stabilized narrow band (~3 GHz) fiber gratings. A fiber based optical circulator and an inline fiber amplifier provide the desired isolation and the net gain for the selected frequency. Also rapid (~2 sec.) alternating measurements of the 2^3 S_1-2^3 P_0 interval for both species of helium is achieved with a custom fiber laser for simultaneous optical pumping. A servo-controlled retro-reflected laser beam eliminates residual Doppler effects during the isotope shift measurement. An improved detection design and software control makes negligible subtle potential biases in the data collection. With these advances, combined with new internal and external consistency checks, we are able to obtain results consistent with the best previous measurements, but with substantially improved precision. Our measurement of the 2^3 S_1-2^3 P_0 isotope shift between 3He and 4He is 31 097 535.2 (5) kHz. The most recent theoretic calculation combined with this measurement yields a new determination for nuclear size differences between 3He and 4He: ∆r_c=0.292 6 (1)_exp (8)_th (52)_exp fm, with a precision of less than a part in 〖10〗^4 coming from the experimental uncertainty (first parenthesis), and a part in 〖10〗^3 coming from theory. This value is consistent with electron scattering measurement, but a factor of 10 more precise. It is inconsistent (4 sigma) with a recent isotope shift measurement on another helium transition (2^1 S_0-2^3 S_1). Comparisons with ongoing muonic helium measurements may provide clues to the origin of what is currently called the proton puzzle: electronic and muonic measurements of the proton size do not agree. In the future, the experimental improvements described here can be used for higher precision tests of atomic theory and quantum electrodynamics, as well as an important atomic physics source of the fine structure constant.

Die vorliegende Arbeit befasst sich mit therapierelevanten Faktoren bei distalen Radiusfrakturen. Auf der Grundlage der nach AO klassifizierten, distalen Radiusfrakturen werden sowohl verletzungsbedingte, als auch therapiebedingte Einflußfaktoren hinsichtlich des klinisch-radiologischen Ergebnisses untersucht. Es erfolgt die Darstellung der Komplikationshäufigkeit bei operativ und konservativ versorgten distalen Radiusfrakturen. Diese wird in Zusammenhang mit unfall-und patientenbezogenen Faktoren, Begleitverletzungen und therapiebezogenen Einflußfaktoren untersucht und am klinisch-radiologischen Ergebnis gemessen. Zur Objektivierung der klinisch-radiologischen Nachuntersuchung dienen der DASH-Score, der Gartland und Werley-Score (modifiziert nach Sarmiento) und der Stewart Score.

This study produced and analyzed shaped tungsten wire tips formed through electrochemical etching. Specifically, the cone length and the radius of curvature of the tip were analyzed. Having the tips move dynamically through an electrolytic solution, such as potassium hydroxide, and tuning the initial starting depth of the tungsten wire along with the dynamic speed of the tungsten wire as it passed throughout the solution allowed various types of tip profiles to be produced. The tip's radius of curvature was able to be reproduced with an accuracy between 88 - 92 %. The method provided would be applicable for the production of various styles of liquid-metal ion source (LMIS) probes and scanning probe microscope (SPM) tips.

Introduction: Distal radius fractures (DRF’s) are one of the most common types of fractures,especially in elderly women. In the last decade, there has been a shift in the treatment methodemployed for DRF’s from the traditional non-operative to an operative method using plates andscrews even though there is no evidence to suggest that this method has superior outcomes. Aim: The primary objective of this study was to identify risk factors for complications and reoperationsin the treatment of DRF’s. Method: The study was designed as a retrospective cohort study. Patients treated for DRF’sbetween 2016-2017 were included through the Swedish Fracture Register and complementedwith the patients’ charts and classification of X-Ray Images from The Orthopedic Clinic at TheCentral Hospital in Karlstad. The risk for re-operation was valued through treatment methodsand fracture classification and presented as Odds Ratio. Result: Positive ulnar variance was correlated to having an increased risk for re-operation, OR4.8 (95% CI 1.7-13.8). Those who had volar comminution in their fracture had a greater risk forre-operation, OR 12.4 (95% CI 4.6-34.1, p&lt;0.001), but also a greater risk for correctiveosteotomy, OR 12.6 (95% CI 1.4-113.9, p=0.024). Conclusion: Volar comminution and positive ulnar variance are associated with an increasedrisk for re-operation. However, the degree of the risk is difficult to measure due to the lowincidence of re-operations.