Toppeffekter används av elnätsbolag för att dimensionera elnätet, vilket blir allt viktigare för varje år. Fler och fler invånare och företag ökar sin elkonsumtion och förväntar sig en driftsäker och stabil elförsörjning. Det finns två vanliga metoder att beräkna toppeffekter. Första sättet är Velanders formel som är en enkel metod för att uppskatta toppeffekter. Velanders formel behöver bara årsenergi och vetskap om kundkategori med tillhörande Velanderkonstanter för beräkning av uppskattad toppeffekt. Sedan finns den mer komplexa typkurvemetoden som behöver flera olika parametrar, t.ex. graddagtal, dygnsmedeltemperatur, gränssannolikhet och kundkategori. Detta examensarbete undersöker en enkel metod för att ta fram konstanter till Velanders formel för beräkning av toppeffekter. Detta genomfördes med hjälp av regressionsanalys av historiska elanvändningsdata från Mälarenergi Elnät AB:s (MEE) kunder från 12 olika kundkategorier. Detta på grund av att MEE önskade att utveckla en metod för att ta fram konstanter till Velanders formel baserad på historiska elanvändningsdata. Metoden för att ta fram konstanter till Velanders formel går ut på att med hjälp av MATLAB utföra en regressionsanalys på simulerade kundgrupper skapade från timvis historiska elanvändningsdata. En kurva baserad på Velanders formel tas sedan fram som beskriver den övre gränsen till toppeffekterna för de simulerade kundgrupperna. Från kurvan fås sedan de Velanderkonstanter som söks. Resultaten av den undersökta metoden presenteras i form av grafer och tabeller för tre utvalda kundkategorier. Alla kategorier och deras resultat finns som bilagor till rapporten. Valideringen av resultaten och metoden gjordes med hjälp av korsvalidering och jämförelse mot heterogena simulerade kundgrupper. Känslighetsanalysen visar att den undersökta metoden var känslig för flera faktorer såsom kategorisering av kunder, tidsspann för historiska elanvändningsdata, antal simulerade kundgrupper och kundantal. Med tillräcklig dimensionering av dessa faktorer bedömdes metoden vara användbar. Resultaten visade på att de framtagna Velanderkonstanterna gav en god uppskattning av toppeffekter för de kundkategorier som undersökts. Jämförelse av de uppskattade toppeffekterna och de observerade visade på att det fanns en viss differens mellan dem. Detta var dock förväntat eftersom de uppskattade toppeffekterna ska avspegla den övre toppeffektsgränsen. / This degree project has examined a simple method aiming to obtain coefficients for Velanders formula which purpose is to calculate peak loads. This was done by using regression analysis on historical data on consumption of electricity from 12 different customer categories acquired from Mälarenergi Elnät AB (MEE). The reason being that MEE wanted to examine a method which could obtain coefficients for Velanders formula based on hourly historical electricity consumption data. The method for obtaining Velander coefficients uses MATLAB to do regression analysis on simulated customer groups, created from hourly historical electricity consumption data. The Velander coefficients are then obtained from a regression curve based on Velanders formula. Results from the evaluation of the method is presented with the help of plots and tables for three chosen customer categories. Validation of the method was done by cross-validation and comparison against heterogeneous customer groups. Sensitivity analysis showed the examined method to be sensitive to several factors such as categorization of customers, the timespan of historical electricity consumption data, the number of simulated customer groups that were used and how many customers a category contained. By dimensioning these factors carefully, the method examined was assessed to be viable. The results indicated that the obtained Velander coefficients gave a good estimation of the peak loads for the chosen customer categories. Comparison between the estimated and observed peak loads indicated that there was a certain difference between them. This was to be expected since the estimated peak loads are to reflect the upper peak load limit.

The Thesis deals with the questions of psychosocial load at work for nurses and social workers. The Thesis is divided into two sections. The theoretical part deals with definitions of terms like caring professions, load and stress, then load at work and psychosocial load. There is also a brief characteristic of the professions of a nurse and a social worker. The aim of the empiric part was to find out on a selected sample of respondents (i.e. nurses and social workers) how the respondents perceive the character of their psychosocial load at work and whether they are at risk of burnout syndrome, to find out whether nurses or social workers perceive the psychosocial load more intensely and whether there is a difference in the risk of burnout syndrome between them. A quantitative questioning method and questionnaire technique were applied on data collection and processing in the research part of the Thesis. An anonymous questionnaire was used for the investigation. The questionnaire preparation was based on a questionnaire provided by my thesis guide. The original questionnaire was more extensive and was only designed for nurses, which was why I had to select suitable items and add some special items applicable on nurses as well as social workers. The questionnaire consisted mainly of closed questions where the respondents chose from five answers the one best corresponding with their own opinion. I set 3 hypotheses before starting the research itself. The questionnaire answers were processed both, manually by means of the stroke method and by a statistic programme SPSS. Segment and bar graphs in Microsoft Office Excel were used for graphical interpretation of the results. After evaluation of the questionnaire research results I found out that the previously set hypothesis H1 suggesting that nurses and social workers perceive various elements of their psychosocial load differently, was confirmed, hypothesis H2 suggesting that nurses are more loaded by the work with patients/clients than social workers was not confirmed, and hypothesis H3 suggesting that nurses are at higher risk of burnout syndrome than social workers was confirmed. The results of my thesis may serve to inform general public as well as professionals on the problems in question. They may also serve as a possible incentive for managerial staff to pay higher attention to the problems of psychosocial load at work among caring professions at individual medical care facilities. The results may also serve as a base for further studies and research in the field.

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As more online services are migrated from monolithic systems into decoupled distributed micro services, the need for efficient internal load balancing solutions increases. Today, there exists two main approaches for load balancing internal traffic between micro services. One approach uses either a central or sidecar proxy to load balance queries over all available server endpoints. The other approach lets client themselves decide which of all available endpoints to send queries to. This study investigates a new approach called lookaside load balancing. This approach consists of a load balancer that uses the control plane to gather a list of service endpoints and their current load. The load balancer can then dynamically provide clients with a subset of suitable endpoints they connect to directly. The endpoint distribution is controlled by a lookaside load balancing algorithm. This study presents such an algorithm that works by changing the endpoint assignment in order to keep current load between an upper and lower bound. In order to compare each of these three load balancing approaches, a test environment in Kubernetes is constructed and modeled to be similar to a real service mesh. With this test environment, we perform four experiments. The first experiment aims at finding suitable settings for the lookaside load balancing algorithm as well as a baseline load configuration for clients and servers. The second experiments evaluates the underlying network infrastructure to test for possible bias in latency measurements. The final two experiments evaluate each load balancing approach in both high and low load scenarios. Results show that lookaside load balancing can achieve similar performance as client-side load balancing in terms of latency and load distribution, but with a smaller CPU and memory footprint. When load is high and uneven, or when compute resource usage should be minimized, the centralized proxy approach is better. With regards to traffic flow control and failure resilience, we can show that lookaside load balancing is better than client-side load balancing. We draw the conclusion that lookaside load balancing can be an alternative approach to client-side load balancing as well as proxy load balancing for some scenarios. / Då fler online tjänster flyttas från monolitsystem till uppdelade distribuerade mikrotjänster, ökas behovet av intern lastbalansering. Idag existerar det två huvudsakliga tillvägagångssätt för intern lastbalansering mellan interna mikrotjänster. Ett sätt använder sig antingen utav en central- eller sido-proxy for att lastbalansera trafik över alla tillgängliga serverinstanser. Det andra sättet låter klienter själva välja vilken utav alla serverinstanser att skicka trafik till. Denna studie undersöker ett nytt tillvägagångssätt kallat extern lastbalansering. Detta tillvägagångssätt består av en lastbalanserare som använder kontrollplanet för att hämta en lista av alla serverinstanser och deras aktuella last. Lastbalanseraren kan då dynamiskt tillsätta en delmängd av alla serverinstanser till klienter och låta dom skapa direktkopplingar. Tillsättningen av serverinstanser kontrolleras av en extern lastbalanseringsalgoritm. Denna studie presenterar en sådan algoritm som fungerar genom att ändra på tillsättningen av serverinstanser för att kunna hålla lasten mellan en övre och lägre gräns. För att kunna jämföra dessa tre tillvägagångssätt för lastbalansering konstrueras och modelleras en testmiljö i Kubernetes till att vara lik ett riktigt service mesh. Med denna testmiljö utför vi fyra experiment. Det första experimentet har som syfte att hitta passande inställningar till den externa lastbalanseringsalgoritmen, samt att hitta en baskonfiguration för last hos klienter or servrar. Det andra experimentet evaluerar den underliggande nätverksinfrastrukturen för att testa efter potentiell partiskhet i latensmätningar. De sista två experimenten evaluerar varje tillvägagångssätt av lastbalansering i både scenarier med hög och låg belastning. Resultaten visar att extern lastbalansering kan uppnå liknande prestanda som klientlastbalansering avseende latens och lastdistribution, men med lägre CPU- och minnesanvändning. När belastningen är hög och ojämn, eller när beräkningsresurserna borde minimeras, är den centraliserade proxy-metoden bättre. Med hänsyn till kontroll över trafikflöde och resistans till systemfel kan vi visa att extern lastbalansering är bättre än klientlastbalansering. Vi drar slutsatsen att extern lastbalansering kan vara ett alternativ till klientlastbalansering samt proxylastbalansering i vissa fall.

In the past, the disagreement of near-threshold fatigue-crack growth (FCG) rate data generated from constant Kmax tests, high load ratio (minimum to maximum load) constant R tests, and ΔKeff based data was a mysterious issue. Because of the disagreement, a variety of test or analysis methods were created to correlate FCG rate data. It was suspected that the ASTM threshold test method using load reduction was inducing remote crack closure due to plastically deformed material, which caused elevated thresholds and slower rates than steady-state behavior. The first goal of this study was the development of a test method to eliminate remote closure during threshold testing. In order to avoid/minimize remote closure effect, compression-precracking methods were used to initiate a crack from a starter notch on compact specimens. Two materials with different fatigue crack surface profiles (flat or very rough) were tested and the results generated from the conventional ASTM precracking method and the compression-precracking test method were compared. In order to understand the disagreement of near-threshold data, crack-opening load measurements were performed from locally (near crack tip) installed strain gages instead of the remote gage (i.e., back face gage). Some careful specimen preparations were performed to avoid out-of-plane bending, to maintain straight crack fronts, and to ensure testing system linearity. It was known that remote gages, such as crack-mouth- opening-displacement-gages were insensitive to measuring load-strain records near threshold. By using local gages, the crack closure effects were clearly observed even in high load ratio (R) tests, like or higher than R = 0.7, and constant Kmax tests, which were believed to be crack closure free. By measuring load-reduced-strain records from local gages, crack-opening loads were able to correlate FCG rate data and showed that ΔKeff-rate data was unique for a wide variety of materials. By comparing (ΔKeff)th values, it may provide reasonable guidance for the material resistance against FCG. Because of “high R crack closure”, some theories considered in the past may need to be reconsidered. First, constant Kmax tests are not entirely crack-closure free. Second, there is no critical load ratio, Rc, to indicate the transition from crack-closure affected to crack-closure free data, and Kmax effects that appear in ΔKth-Kmax relations. Research has shown that the three dominate crack-closure mechanisms (plasticity-, roughness- and debris-induced crack closure) FCG rate behavior in the threshold regime from low to high load ratios.

No / The ever increasing user QoS demands and emergence of new user applications make job of network operators and manufacturers more challenging for efficiently optimisation and managing radio resources in radio the radio resources pools of different wireless networks. A group of strategies or mechanisms which are collectively responsible for efficient utilisation of radio resources available within the Radio Access Technologies (RAT) are termed as Radio Resource Management (RRM). The traditional RRM strategies are implemented independently in each RAT, as each RRM strategy considers attributes of a particular access technology. Therefore traditional RRM strategies are not suitable for heterogeneous wireless networks. Common Radio Resource Management (CRRM) or joint radio resource management (JRRM) strategies are proposed for coordinating radio resource management between multiple RATs in an improved manner. In this paper a fuzzy algorithm based CRRM strategy is presented to efficiently utilise the available radio resources in heterogeneous wireless networks. The proposed CRRM strategy balances the load in heterogeneous wireless networks and avoids the unwanted congestion situation. The results such as load distribution, packet drop rate and average throughput at mobile nodes are used to demonstrate the benefits of load balancing in heterogeneous wireless networks using proposed strategy.

more funding must be allocated for their rehabilitation or replacement. The Federal Highway Administration's (FHWA) Long-Term Bridge Performance (LTBP) Program has been developed to help bridge stakeholders make the best decisions concerning the allocation of these funds. This is done through the use of high quality data obtained through numerous testing processes. As part of the LTBP Pilot Program, researchers have performed live load tests on the U.S. Route 15 Southbound bridge over Interstate-66. The main performance and behavior characteristics focused on are service strain and deflection, wheel load distribution, dynamic load allowance, and rotational behavior of bridge bearings. Data from this test will be used as a tool in developing and refining a plan for long-term bridge monitoring. This includes identifying the primarily loaded girders and their expected range of response under ambient traffic conditions. Information obtained from this test will also aid in the refinement of finite element models by offering insight into the performance of individual bridge components, as well as overall global behavior. Finally, the methods and results of this test have been documented to allow for comparison with future testing of this bridge, which will yield information concerning the changes in bridge behavior over time. / Master of Science

No / In the telecommunication networks the introduction of Next Generation Wireless Networks (NGWN) has been described as the most significant change in wireless communication. The convergence of different access networks in NGWN allows generalized mobility, consistency and ubiquitous provision of services to mobile users. The general target of NGWN is to transport different types of information like voice, data, and other media like video in packets form like IP. The NGWNs offer significant savings in costs to the operators along with new and interesting services to the consumers. Major challenges in NGWN are efficient resource utilization, maintaining service quality, reliability and the security. This paper proposes a solution for seamless load aware Radio Access Technology (RAT) selection based on interworking of different RATs in NGWN. In this paper novel load balancing algorithms have been proposed which have been simulated on the target network architecture for TCP data services. The IEEE 802.21 Media Independent Handover (MIH) is utilized in load balancing specifically for mobility management, which enable low handover latency by reducing the target network detection time. The proposed method considers the network type, signal strength, data rate and network load as primary decision parameters for RAT selection process and consists of two different algorithms, one located in the mobile terminal and the other at the network side. The network architecture, the proposed load balancing framework and RAT selection algorithms were simulated using NS2. Different attributes like load distribution in the wireless networks and average throughput to evaluate the effects of load balancing in considered scenarios.