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Design Considerations and Guidelines for Continuous Helical and Helical Piles in Saturated Sand
No full textZero-Knowledge Shuffle Improvement in Ethereum Single Secret Leader Election
No full textAs Ethereum is one of the most popular blockchains, it is naturally targeted by various attacks, which aim for example to disrupt the service or steal tokens. Among the possible attacks, in de-anonymization attacks, an adversary canobtain validator IP addresses and then perform a Denial-of-Service attack on them. To mitigate this attack, the Ethereum foundation is proposing Whisk, a Single Secret Leader Election protocol that uses a zero-knowledge proof called Curdleproofs to prove the validity of a shuffle of validators. One limitationof Curdleproofs is the shuffle size, which must be a power of two, limiting the options of how many validators can be. This paper overcomes this limitation by proposing CAAUrdleproofs, a modified version of Curdleproofs that incorporatesSpringproofs. Our experiments show that CAAUrdleproofs has a performance advantage for any shuffle size that is not a power of two and that this advantage increases as the shuffle size decreases below a power of two
Assimilation of Zenith Wet Delay observations using the ensemble Kalman Filter in a Poly-ZWD empirical model over the USA
No full textModeling the spatial and temporal variability of water vapor in the lower atmosphere is crucial for meteorological and geodetic applications, as it directly influences weather prediction and satellite-based positioning. However, traditional empirical models often struggle to capture rapid water vapor fluctuations, limiting their accuracy and practical utility. These models are also typically grid-based and involve numerous parameters, making real-time calibration against current observations challenging. To address these limitations, this study applies an ensemble-based Calibration and Data Assimilation (C/DA) approach using the Ensemble Kalman Filter (EnKF), which sequentially adjusts model parameters based on observational data, thereby improving short-term prediction accuracy. Specifically, we enhance the estimation of Zenith Wet Delay (ZWD) through the development of a regional empirical model, Poly-ZWD. This model employs third-order polynomials for horizontal variations due to their flexibility in capturing spatial trends with fewer coefficients, and B-spline functions for temporal variations because of their compact support and strong local control, which enable smooth and efficient time-dependent modeling. The model was built using ERA5 reanalysis data from 2016 to 2020. Poly-ZWD spans the contiguous United States (27°–49°N, 94°–68°W) and incorporates 680 parameters, which collectively capture the spatial and temporal behavior of ZWD across the domain. These parameters were recalibrated using GNSS-derived ZWD observations from 460 stations across the U.S. for the year 2021, improving alignment with real-world atmospheric conditions and enhancing model performance compared to the original PCA-ZWD derived coefficients. The recalibrated model, referred to as C/DA Poly-ZWD, was evaluated against ZWD estimates from 15 independent GNSS test stations and 7 radiosonde sites. Results show that the proposed model achieves a root mean square error (RMSE) of approximately 1.1 cm, outperforming both ERA5 and GTrop models. While RMSE increases gradually from 1.1 cm to around 6 cm over a 24-h forecast horizon, the calibrated model consistently maintains superior accuracy compared to the considered empirical models. Notably, the C/DA approach provides more accurate short-term ZWD predictions than ERA5 within a 3-h forecast window. These findings highlight the effectiveness of ensemble-based C/DA techniques in enhancing real-time ZWD modeling capabilities, with promising implications for improving GNSS-based positioning accuracy and short-term weather forecasting.</p
Enacting Future Robots with Namibian Children
No full textIn this paper, we describe the co-design of future domestic social robots with 19 students from a primary school in Namibia. The aim of the study was to explore how the students imagine future robots to be taking care of everyday things and conversing with children. We engaged in two co-design workshops in which the robot was visualised and enacted, respectively. Using a participatory approach, the study provides new insights of children’s perspectives on robots from a diverse cultural background related to their situated context and understanding of technical and social interactions
Kapitel 1: Hvad betyder ”retten til effektive retsmidler” i menneskeretten?
No full textEMRK art. 13 om effektive retsmidler som menneskerettighe
Debulking surgery after muscular paraffin oil injections: Effects on calcium homeostasis and patient satisfaction
No full textContextCosmetic paraffin oil injections can lead to granuloma formation, causing hypercalcemia and kidney failure.ObjectiveThis study explores whether debulking surgery is an effective treatment for improving calcium homeostasis, inflammation, and clinical symptoms.MethodsIn a retrospective study, we reviewed 33 patients undergoing debulking surgery. Changes in calcium, inflammatory markers, and renal function from baseline up to 12 months after surgery were assessed. Patients were interviewed after surgery.ResultsThe patients were 34.6 years of age (SD 6.9) and had 1104 grams (SD 591) of granuloma tissue removed following injection of 1329 mL (SD 803) paraffin oil 7.9 years (SD 3.2) earlier. Seventeen patients had hypercalcemia and experienced a significant decline in ionized calcium from 1.48 mmol/L (SD 0.16) at baseline to 1.33 mmol/L (SD 0.03) at 12 months (P < .002), although only 4 men (23.5%) became normocalcemic. Serum ferritin was reduced by 50% after 12 months (P = .048). Sixteen patients were normocalcemic and had no change in calcium homeostasis but experienced a 20% drop in serum ferritin levels (P = .025) after surgery. Fifteen patients completed all their planned surgeries within the study period and experienced a decline in serum ionized calcium (P = .031), ferritin (P = .011), and interleukin 2-receptor (P = .037). A survey showed that 55% of patients reported postoperative satisfaction scores of 10/10, and 59% of the patients reported reduced pain.ConclusionSurgery improved calcium homeostasis in a fraction of patients and reduced inflammation and subjective symptoms such as pain and mental well-being in a patient group left with few treatment options except high-dose prednisolone
Feasibility Studies of Green Hydrogen Production Using Photovoltaic Systems in Iran's Southern Coastal Regions
No full textThis study investigates the production of green hydrogen in the southern coastal cities of Iran, leveraging local advantages. These include the high potential for photovoltaic generation, the need for desalination power plants, and access to the sea and ports, all of which make the southern coasts of Iran favorable for green hydrogen production. However, the approach presented in this paper can also be applied to similar regions.Initially, the optimal size of the electrolyzer for maximum hydrogen production at each location is determined. To compare the potential of these locations, the levelized cost of energy (LCOE) and levelized cost of hydrogen (LCOH) are calculated, and the effects of variables such as the discount rate and water price on these costs are analyzed. Unlike many existing studies, this research accurately models the impact of temperature on the techno-economic outputs of the photovoltaic power plant and electrolyzer and compares it to a scenario where the temperature effect is not considered. Additionally, the study examines the minimum power required for the electrolyzer to operate efficiently, avoiding low-efficiency operations.The results indicate that ignoring the temperature effect leads to an overestimation of electrolyzer power and hydrogen production. The discount rate significantly impacts LCOE and LCOH, while the cost of water for hydrogen production has a negligible effect on LCOH. This is due to the higher influence of energy costs and electrolyzer investment on LCOH
Day-Ahead Multi-Criteria Energy Management of a Smart Home Under Differ-ent Electrical Rationing Scenarios
No full textWith the recent global energy crisis, some countries have implemented electrical rationing (ER), making it necessary for smart homes to play a pivotal role in optimizing energy consumption and contributing to sustainable practices. To effectively manage smart home consumption, a stochastic programming approach for a grid-connected smart home energy management system (SHEMS) is proposed in this paper. The system includes PV, battery, diesel, and gas-based heating/cooling systems (HCS). Additionally, a demand response program (DRP) has been employed under time-of-use tariffs in the Syrian energy market. The main objective is to minimize the day-ahead expected cost and consumer discomfort by optimizing the operation of dispatchable units and loads. To manage the risks associated with the expected cost due to potential uncertainties in PV energy generation and electrical rationing programs, the conditional value-at-risk (CVaR) approach is adopted. Two methods are proposed to model the uncertainty in PV energy generation; interval bands and interval-based scenarios. The problem is modeled as a mixed-integer non-linear programming (MINLP) model, and coded in GAMS to test different cases. Based on the results obtained, substantial reductions reached 56.2% in worst-case cost scenarios when employing concurrent DRP-risk management.<br/
Certolizumab pegol, abatacept, tocilizumab or active conventional treatment in early rheumatoid arthritis: 48-week clinical and radiographic results of the investigator-initiated randomised controlled NORD-STAR trial
No full textBackground: The optimal first-line treatment in early rheumatoid arthritis (RA) is debated. We compared clinical and radiographic outcomes of active conventional therapy with each of three biological treatments with different modes of action.Methods: Investigator-initiated, randomised, blinded-assessor study. Patients with treatment-naïve early RA with moderate-severe disease activity were randomised 1:1:1:1 to methotrexate combined with (1) active conventional therapy: oral prednisolone (tapered quickly, discontinued at week 36) or sulfasalazine, hydroxychloroquine and intra-articular glucocorticoid injections in swollen joints; (2) certolizumab pegol; (3) abatacept or (4) tocilizumab. Coprimary endpoints were week 48 Clinical Disease Activity Index (CDAI) remission (CDAI ≤2.8) and change in radiographic van der Heijde-modified Sharp Score, estimated using logistic regression and analysis of covariance, adjusted for sex, anticitrullinated protein antibody status and country. Bonferroni's and Dunnet's procedures adjusted for multiple testing (significance level: 0.025).Results: Eight hundred and twelve patients were randomised. Adjusted CDAI remission rates at week 48 were: 59.3% (abatacept), 52.3% (certolizumab), 51.9% (tocilizumab) and 39.2% (active conventional therapy). Compared with active conventional therapy, CDAI remission rates were significantly higher for abatacept (adjusted difference +20.1%, p<0.001) and certolizumab (+13.1%, p=0.021), but not for tocilizumab (+12.7%, p=0.030). Key secondary clinical outcomes were consistently better in biological groups. Radiographic progression was low, without group differences.The proportions of patients with serious adverse events were abatacept, 8.3%; certolizumab, 12.4%; tocilizumab, 9.2%; and active conventional therapy, 10.7%.Conclusions: Compared with active conventional therapy, clinical remission rates were superior for abatacept and certolizumab pegol, but not for tocilizumab. Radiographic progression was low and similar between treatments