Simulation of a vertical bifacial PV system compared to measured values

Photovoltaic (PV) systems have gained great interest the recent years with an increasing rate of installed capacity. In addition to the monofacial solar panels, the interest in bifacial solar panels, with an expected market share of 30.0 % by 2030, increases. The bifacial solar panels utilize irradiance on both the front and rear sides of the panel to generate energy. Hence, they are able to generate more energy than monofacial solar panels, making them interesting due to the demand for energy-efficient solar panels. Over Easy Solar AS offers vertically mounted bifacial solar panels with a height of approximately 22.0 cm. Compared to conventional solar panels, they do not need intrusive fasteners and heavy ballast. Thereby, the solar panels are suitable for many flat roofs and green roofs as light and water are provided to the plants underneath. At the Institute for Energy Technology (IFE) at Kjeller, a test site including solar panels from Over Easy Solar AS has been mounted. As the technology from Over Easy Solar AS was introduced in 2021, addressing the performance using software to simulate the irradiance and power output, with possible factors affecting the simulations has not been researched much. In this thesis, the software bifacial_radiance was assessed by creating a 3D model and simulating the irradiance using backward ray tracing for the test site at IFE. Even though bifacial_radiance is a time-consuming software, simulations were performed for clear-sky days, overcast days, and days with varying weather, for all seasons in Norway. Overall, the results from bifacial_radiance show an overestimation of the irradiance compared to measured irradiance with a percentage difference of 5.06 % – 16.54 %, but the model gives a rough estimate of the expected irradiance. Still, there are some days where there is good compliance between simulated and measured irradiance, and other days with a large deviation, especially during the winter. There are many possible explanations for the deviation between simulated and measured irradiance such as albedo, shading, and snow. Differences between the 3D model and the test site, such as orientation, materials, surrounding objects, and positioning of objects are other factors that may affect the irradiance. This thesis thoroughly and systematically addresses factors that may affect the simulated and measured irradiance for a PV system. The simulated power using pvlib shows an overestimation of the DC and AC power compared to the measured values. Possible explanations are system losses such as shading and cable losses. Snow covering the solar panels is also a significant factor that may affect the measured power and cause a larger deviation in the results. When simulating the DC energy for a longer period of time, the percentage difference between measured and simulated energy varies in the range of 28.29 % – 119.58 %. Hence, further work and implementation of the factors such as shading and snow should be done to develop a more accurate model for simulating power and energy

School-leaders role in school development work – superperson or teamleader?

Mastergradsoppgave i utdanningsledelse, Høgskolen i Innlandet, 2020.Norsk: En viktig forutsetning for elevenes læring, er lærere med god pedagogisk og faglig kompetanse, og skoleledere som legger til rette for lærernes læring (Hattie, 2013). Forskningen peker også på verdien av skoleeiernivået for elevenes læring (Paulsen og Hjertø, 2019: Paulsen, 2019). den røde tråden i denne masteroppgaven er valgt med utgangspunkt i dette, og jeg ser på hvordan forbedringsarbeidet i skolen gjennom utvikling av profesjonelle læringsfellesskap, hvordan man som skoleleder initierer og leder forbedringsarbeidet og hvordan de opplever behov for støttesystemer i dette arbeidet. Målet har vært at jeg gjennom studien kan presentere noen tanker og handlesett for hvordan man som skoleleder kan legge til rette for lærernes læring. Med utgangspunkt i erfaringer fra egen skolehverdag og teori og forskning innenfor profesjonelle læringsfellesskap, elevsentrert ledelse, skoleeierskapet, læring og støttesystemer, har jeg følgende tre problemstillinger: Hvordan kan rektor, og ledergruppa, tilrettelegge for utvikling av profesjonelle læringsfellesskap i egen organisasjon? Hvordan initierer og følger rektor opp skolens forbedringsarbeid med utgangspunkt i kartleggingsresultater? Hvordan oppleves behovet for støttesystemer av skoleledere når de skal legge til rette for lærernes læring? Studien har en kvalitativ forskningsstrategi med fenomenologisk tilnærming. I artikkel 1 er det en casestudie med observasjoner og samtaleintervjuer, i artikkel 2 er det en casestudie med et semistrukturert intervju, og artikkel 3 er en dokumentanalyse av de to foregående artiklene. Mine funn tyder på at ved god tilrettelegging og oppfølging fra skoleleder, er det gode forutsetninger for lærernes læring. Funnene indikerer at skoleleders opplevelse er å stå mye alene om forbedringsarbeidet, uten nok støtte fra skoleeier, og det kan forringe kvaliteten på forbedringsarbeidet i skolen. Mine funn peker også på hvordan man som skoleleder kan tilrettelegge og drive forbedringsarbeid, men at det vil være fornuftig å delegere og fordele arbeidsoppgaver for å skape mest mulig tid til forbedringsarbeidet.English: Teachers who hold a high level of educational and professional competence, as well as school leaders who facilitate teacher learning, are important prerequisites for pupil’s learning. Research also refers to the value of school authority for student learning (Paulsen and Hjertø, 2019: Paulsen, 2019). The master’s thesis is based upon this assumption, looking at school improvement work through the development of professional learning communities, how a school leader can initiate and lead the improvement work and how these leaders experience the need for support systems in this work. This resource aims to present some thoughts and actions on how a school leader can better facilitate teacher learning. Based on experiences from my own work-life within the school system, as well as theory and research in professional learning communities, student-centered leadership, school ownership, learning, and support systems, I have landed on the following three issues: How can the principal, and the management team, facilitate the development of professional learning communities in their organization? How does the principal initiate and follow up on the school's improvement work based on survey results? How is the need for support systems experienced by school principals when they are to facilitate teacher learning? The study has a qualitative research strategy with a phenomenological approach. Article 1 consists of a case study with observations and interviews, Article 2 consists of a case study with a semi-structured interview, and Article 3 is a document analysis of the two previous articles. My findings indicate that good facilitation and follow-up by the school principal provides a good foundation for teacher learning. The findings indicate that the school leader’s experience carries too much responsibility for the improvement work without sufficient support from the school owner, and this can impair the quality of the improvement work in the school. My findings also point to how a school leader can better organize and conduct improvement work, but with emphasis on the fact that it would make sense to delegate and distribute tasks to create as much time as possible to focus on the improvement work

New Malignancies after Squamous Cell Carcinoma and Melanomas: A Population-Based Study from Norway

Skin cancer survivors experience an increased risk for subsequent malignancies but the associated risk factors are poorly understood. This study examined the risk of a new primary cancer following an initial skin cancer and assessed risk factors associated with second primary cancers

Sociodemographic factors, health indicators and lifestyle factors among participants in BreastScreen Norway 2006-2016 – a cohort profile

Purpose: To collect information on sociodemographic factors, health indicators, and lifestyle factors in women who attended the nationwide breast cancer-screening program, BreastScreen Norway, with the aim of investigating how these factors influence the risk of breast cancer, other cancer types, and cancer-related outcomes. Participants: The cohort data includes self-reported responses to questionnaires from 554,149 women aged 50- 69 years, who attended BreastScreen Norway during the data collection period, 2006-2016. Findings to date: Information about sociodemographic factors, health indicators, and lifestyle factors was collected for the current time and retrospectively back to birth. For the cohort, we have complete mammographic screening data, including information about 24,000 breast cancer cases and other cancer types from the Cancer Registry of Norway. These outcomes are aggregating continuously. Data from the cohort have been utilized in studies related to breast cancer and menopausal status. Future projects: Data will be utilized in studies related to tumour growth and risk of breast cancer as well as other cancer types, in addition to overall and cancer-specific death. Registration: The cohort profile is not registered in Clinical Trials

Subsite-Specific Dietary Risk Factors for Colorectal Cancer: A Review of Cohort Studies

Objective. A shift in the total incidence from left- to right-sided colon cancer has been reported and raises the question as to whether lifestyle risk factors are responsible for the changing subsite distribution of colon cancer. The present study provides a review of the subsite-specific risk estimates for the dietary components presently regarded as convincing or probable risk factors for colorectal cancer: red meat, processed meat, fiber, garlic, milk, calcium, and alcohol. Methods. Studies were identified by searching PubMed through October 8, 2012 and by reviewing reference lists. Thirty-two prospective cohort studies are included, and the estimates are compared by sex for each risk factor. Results. For alcohol, there seems to be a stronger association with rectal cancer than with colon cancer, and for meat a somewhat stronger association with distal colon and rectal cancer, relative to proximal colon cancer. For fiber, milk, and calcium, there were only minor differences in relative risk across subsites. No statement could be given regarding garlic. Overall, many of the subsite-specific risk estimates were nonsignificant, irrespective of exposure. Conclusion. For some dietary components the associations with risk of cancer of the rectum and distal colon appear stronger than for proximal colon, but not for all

Sunscreens With High Versus Low Sun Protection Factor and Cutaneous Squamous Cell Carcinoma Risk: A Population-Based Cohort Study

Evidence on sunscreen use and cutaneous squamous cell carcinoma (cSCC) risk is limited. Most studies have not taken sun protection factor (SPF) into consideration and used nonusers of sunscreen as the reference group. Nonusers are likely a priori at lower cSCC risk than users. No study has investigated the effect of high- versus low-SPF sunscreens on cSCC, appropriately adjusting for time-varying confounding. Using data from the Norwegian Women and Cancer Study (1991–2016), we investigated whether use of SPF ≥15 versus SPF <15 sunscreens reduces cSCC risk. We used a marginal structural Cox proportional hazards model with inverse probability of treatment and censoring weights to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During follow-up of 148,781 women (mean follow-up, 14.3 years), 653 women were diagnosed with cSCC. The effect on cSCC risk of sunscreens with SPF ≥15 versus SPF <15 was close to the null when used at any latitudes (HR = 1.02, 95% CI: 0.82, 1.27) and when used in lower-latitude settings (HR = 1.05, 95% CI: 0.84, 1.32). In conclusion, we found no indication that sunscreens with SPF ≥15 reduced Norwegian women’s cSCC risk more than sunscreens with SPF <15, suggesting that either there is no difference in their effects long-term or the difference is diluted by incorrect application

A protocol for prospective studies 5-hydroxyvitamin D, leptin and b ass index in relation to cutaneou elanoma incidence and survival

Introduction The incidence and mortality rates of cutaneous melanoma (CM) are increasing among fai skinned populations worldwide. Ultraviolet radiation s the principal risk factor for CM, but is also the mai source of 25-hydroxyvitamin D (25(OH)D), which has associated with reduced risk and better prognosis of cancer types. However, both low and high 25(OH)D l have been associated with increased risk of CM. Obe as measured by body mass index (BMI) is associated risk of several cancers and has also been suggested risk factor for CM, and may also be related to insuffi 25(OH)D and/or high leptin levels. Moreover, contract CM diagnosis has been associated with increased ri developing second cancer. We aim to study whether prediagnostic serum levels of 25(OH)D, high prediag evels of BMI and high serum leptin levels influence ncidence, Breslow thickness and CM mortality, and second cancer and survival after a CM diagnosis. Methods and analysis Cohort and nested case–co studies will be carried out using the population-base Janus Serum Bank Cohort (archival prediagnostic se BMI, smoking and physical activity), with follow-up fr 1972 to 2014. Additional data will be received from t Cancer Registry of Norway, the national Cause of De Registry, Statistics Norway (education and occupatio and exposure matrices of UVR. Time-to-event regres models will be used to analyse the cohort data, whil he nested case–control studies will be analysed by conditional logistic regression. A multilevel approach be applied when incorporating group-level data. Ethics and dissemination The project is approved he Regional Committee for Medical Research Ethics and is funded by the Norwegian Cancer Society. Res will be published in peer-reviewed journals, at scient conferences and in the news media