Modellering av tågnät på Arriva DK

Purpose: The purpose of this thesis is to develop two simulation models of Arrivas train network in Denmark to facilitate the process of timetabling. One of the models assumes deterministic times in the other model these times are stochastic. The purpose of the deterministic model is to evaluate if timetables are free from conflicts, a process that currently involves a lot of manual labor. The main goal of the stochastic model is to be able to compare different timetables, using a more realistic model of the train network that compensates for the inherent uncertainties in travel and stop times. The goal is not to develop a finished product for immediate practical implementation. The aim has been to develop a platform and process for modelling and serve as first version for further improvement. Delimitations: The models focus on normal operations. Therefore unexpected events like signal errors, accidents etc. are disregarded. Another delimitation is that the availability of trains and staff, and how it affects the timetable, are disregarded. Additional delimitations are that the model only accounts for Arriva trains and not for their competitors’ trains, and that the decision process for prioritizing trains when conflicts occur is simplified in the simulation models. v Method: The method used in this thesis is a modified version of the 8-step process for large simulation projects in Hillier and Lieberman (2010, pp. 959-963). The process has been implemented in two stages, one for each model. Conclusions: Verification and validation show that the deterministic model is consistent with reality. The model is therefore considered ready to be used as an aid in the process of making new timetables. The stochastic model has been more difficult to validate. This is because the material plan and service plan is not yet included in the simulation model, which makes it hard to compare the simulation results to the observed data for the real system. However, validity has been achieved for the logic of the system, and for the distributions of transport times and number of passengers. We can also conclude that the distributions for the time spent on stations needs to be further investigated and validated. There is also an uncertainty about the rules of prioritization of trains in case there are delays. During the validation of the model, the dataset has shown lack of quality in large parts of the total set. Therefore we recommend Arriva to investigate their data collection. After the quality of the data is improved, we recommend Arriva to implement the service plan and material plan into the simulation model to be able make a fair comparison between observed data and simulation results

Hybrid Positioning Solution Using 5G and GNSS

The importance of accurate position estimation is becoming more necessary as industries and society increasingly rely on autonomous or wireless devices while the capabilities of existing positioning solutions fail to meet the demanding requirements. This situation has provided opportunities for wireless positioning techniques with the rollout of 5G which has led to many enhancements to the network protocol related to positioning. This report investigates the feasibility of meeting these requirements with the use of existing GNSS positioning solutions and yet-to-be implemented 5G positioning methods. We evaluate the performance using different measurements separately as well as a hybridization between them to examine the optimal result. The report also demonstrates the potential of using only a single BS to achieve accurate positioning, which is not possible with e.g. LTE.  The method in this report is based on partly well-proven theory for positioning together with recent developed concepts for radio network localization. By using an advanced simulator that generates realistic signals and measurements in virtual deployments of base-stations and users, our method can be well evaluated, which makes the results interesting for both academia and industry. The results show good potential for both 5G stand-alone positioning as well as hybrid 5G and GNSS positioning. This report demonstrates that a single BS can locate a UE in line-of-sight of 200 meters within 1.5 meters for 80% of the cases without using any GNSS system

Företags värdekedjor inom detaljhandeln – Hur dessa hanterat samhällets digitala transformation

Since the beginning of man, there has been great technological development. Both the industrial revolution and now, industry 4, are good examples of this. This has led to a big change both in our everyday lives as well as for companies and their daily operations. The paper is based on a series of analyses on different documents from the internet, organization documents and documents from public authorities. This will then in turn be combined with a literature review and traditional theories regarding the topic. The paper concludes that customers' changing purchasing behavior has created a need for change in the retail mar. The changing purchasing behavior is attributed to the digitalization of society and customers' new expectations of the companies. To remain relevant in the market, organizations today must meet customers and their expectations through digital portals in a way that did not exist before

Företags värdekedjor inom detaljhandeln – Hur dessa hanterat samhällets digitala transformation

Since the beginning of man, there has been great technological development. Both the industrial revolution and now, industry 4, are good examples of this. This has led to a big change both in our everyday lives as well as for companies and their daily operations. The paper is based on a series of analyses on different documents from the internet, organization documents and documents from public authorities. This will then in turn be combined with a literature review and traditional theories regarding the topic. The paper concludes that customers' changing purchasing behavior has created a need for change in the retail mar. The changing purchasing behavior is attributed to the digitalization of society and customers' new expectations of the companies. To remain relevant in the market, organizations today must meet customers and their expectations through digital portals in a way that did not exist before

Företags värdekedjor inom detaljhandeln – Hur dessa hanterat samhällets digitala transformation

Since the beginning of man, there has been great technological development. Both the industrial revolution and now, industry 4, are good examples of this. This has led to a big change both in our everyday lives as well as for companies and their daily operations. The paper is based on a series of analyses on different documents from the internet, organization documents and documents from public authorities. This will then in turn be combined with a literature review and traditional theories regarding the topic. The paper concludes that customers' changing purchasing behavior has created a need for change in the retail mar. The changing purchasing behavior is attributed to the digitalization of society and customers' new expectations of the companies. To remain relevant in the market, organizations today must meet customers and their expectations through digital portals in a way that did not exist before

Företags värdekedjor inom detaljhandeln – Hur dessa hanterat samhällets digitala transformation

Since the beginning of man, there has been great technological development. Both the industrial revolution and now, industry 4, are good examples of this. This has led to a big change both in our everyday lives as well as for companies and their daily operations. The paper is based on a series of analyses on different documents from the internet, organization documents and documents from public authorities. This will then in turn be combined with a literature review and traditional theories regarding the topic. The paper concludes that customers' changing purchasing behavior has created a need for change in the retail mar. The changing purchasing behavior is attributed to the digitalization of society and customers' new expectations of the companies. To remain relevant in the market, organizations today must meet customers and their expectations through digital portals in a way that did not exist before

Course of Grip Force Impairment in Patients With Early Rheumatoid Arthritis Over the First Five Years After Diagnosis

Objective: Objective measures of function are important in rheumatoid arthritis (RA). The objective of this study was to investigate grip strength in patients with early RA. Methods: An inception cohort of 225 patients with early RA was followed in accordance with a structured protocol. Average and peak grip force values of the dominant hand (measured using a Grippit device [AB Detektor]) were evaluated and compared to expected age- and sex-specific reference values from the literature. Separate analyses were performed for those with limited self-reported disability (Health Assessment Questionnaire disability index [HAQ DI] score ≤0.5) and clinical remission (Disease Activity Score in 28 joints <2.6). Results: Baseline average grip force among RA patients was significantly lower than the corresponding expected value (mean 105N versus 266N; P < 0.001). Observed average and peak grip force values were significantly reduced compared to those expected in women as well as in men over time and at all time points. The average grip force improved significantly from inclusion to the 12-month visit (age-corrected mean change 34N [95% confidence interval 26–43]). At 5 years, the average grip force was still lower than that expected overall (mean 139N versus 244N; P < 0.001), and also among those with HAQ DI scores ≤0.5 and those in clinical remission. Conclusion: Grip strength improved in early RA patients, particularly during the first year. However, it was still significantly impaired 5 years after diagnosis, even among those with limited self-reported disability and those in clinical remission. This suggests that further efforts to improve hand function are important in early RA

The relation between upper extremity joint involvement and grip force in early rheumatoid arthritis : a retrospective study

To investigate the relation between joint involvement in the upper extremities and grip force in patients with early rheumatoid arthritis (RA). An inception cohort of 225 patients with early RA was followed according to a structured protocol. The same rheumatologist assessed all patients for swollen joints and joint tenderness. Grip force was measured (Grippit; AB Detektor, Gothenburg, Sweden) at the same visit. Average grip force values for the dominant hand were expressed as % of expected, based on age- and sex-specific reference values from the literature. Associations between grip force and current synovitis or tenderness of individual joints, and other disease parameters measured at the same visit, were examined. Patients with current synovitis of the wrist joint or ≥ 1 metacarpophalangeal (MCP) joint of the dominant hand had a significantly lower grip force at inclusion, at 1 year and at 5 years. Proximal interphalangeal joint tenderness and MCP joint tenderness were consistently associated with reduced grip force. In multivariate analysis, extensive MCP joint synovitis was associated with lower grip force at inclusion (β − 2.8% per joint; 95% CI − 5.3 to − 0.4), and also at the 1-year follow-up. Patient reported pain scores and erythrocyte sedimentation rates had independent negative associations with grip force at all time points. In patients with early RA, extensive synovitis of the MCP joints was associated with reduced grip force, independently of other upper extremity joint involvement. Pain and inflammation have effects on hand function beyond those mediated by local synovitis

Predictors of unacceptable pain with and without low inflammation over 5 years in early rheumatoid arthritis—an inception cohort study

Abstract Objectives Pain is a major symptom in patients with rheumatoid arthritis (RA). In early RA, pain is usually due to synovitis, but can also persist despite effective anti-inflammatory treatment. The objective of this study was to investigate the pain course over time and predictors of unacceptable pain and unacceptable pain with low inflammation, in patients with early RA. Methods An inception cohort of 232 patients with early RA, recruited in 1995–2005, was followed in a structured programme for 5 years. Pain was assessed using a visual analogue scale (VAS; 0–100). Unacceptable pain was defined as VAS pain > 40 based on the patient acceptable symptom state (PASS) and low inflammation as CRP < 10 mg/l. Baseline predictors of unacceptable pain were evaluated using logistic regression analysis. Results Pain improved significantly during the first 6 months, but then remained basically unchanged. Thirty-four per cent of the patients had unacceptable pain 5 years after inclusion. Baseline predictors of unacceptable pain after 5 years were lower swollen joint counts [odds ratio (OR) 0.71 per standard deviation (95% confidence interval (CI) 0.51–0.99)] and higher VAS for pain and global assessment of disease activity. Unacceptable pain with low inflammation after 5 years was negatively associated with anti-CCP antibodies [OR 0.50 (95% CI 0.22–0.98)]. Conclusion Over one third of the patients had unacceptable pain 5 years after inclusion. Lower swollen joint count was associated with unacceptable pain at 5 years. The results may be explained by the positive effects of treatment on pain related to inflammation. Non-inflammatory long-lasting pain appears to be a greater problem in anti-CCP-negative patients