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This article presents a research approach to enhancing the quality of short-term power output forecasting models for photovoltaic plants using a Long Short-Term Memory (LSTM) recurrent neural network. Typically, time-related indicators are used as inputs for forecasting models of PV generators. However, this study proposes replacing the time-related inputs with clear sky solar irradiance at the specific location of the power plant. This feature represents the maximum potential solar radiation that can be received at that particular location on Earth. The Ineichen/Perez model is then employed to calculate the solar irradiance. To evaluate the effectiveness of this approach, the forecasting model incorporating this new input was trained and the results were compared with those obtained from previously published models. The results show a reduction in the Mean Absolute Percentage Error (MAPE) from 3.491% to 2.766%, indicating a 24% improvement. Additionally, the Root Mean Square Error (RMSE) decreased by approximately 0.991 MW, resulting in a 45% improvement. These results demonstrate that this approach is an effective solution for enhancing the accuracy of solar power output forecasting while reducing the number of input variables.

Objectives: To identify the proportion of atopic dermatitis adult patients having anxiety and depression disorder and measure the relationship between anxiety and depression disorder and characteristics of atopic dermatitis. Materials and Methods: a cross-sectional study with convenience sampling was conducted. Diagnostic criteria for atopic dermatitis were based on modified Hanifin and Raijka criteria and the severity of anxiety - depression disorder was evaluated using HADS (Hospital Anxiety And Depression Scale). Results: 208 patients were enrolled in this study. The percentage of patients with anxiety and subthreshold anxiety were 11.1% and 34.1%, respectively. 5.3% of patients had depression and 39.4% of patients suffered from subthreshold depression. The proportion of patients with mixed anxiety-depressive disorder was 1.44%. Patients with severe atopic dermatitis were more likely to endure anxiety but not depression. Allergies or autoimmune diseases and SCORAD C were two independent risk factors of depression whereas edema and excoriation were two independent risk factors related to anxiety in atopic dermatitis patients. Conclusion: These findings suggest that atopic dermatitis is associated with anxiety and depression. Allergies, autoimmune diseases, pruritus, and insomnia had a correlation with anxiety and depression disorder.

With the average solar radiation reaching up to 5 kWh/m2, Vietnam is considered as a country showing an excellent potential for solar power production. Since the year 2000, there have been a lot of studies about the potential of this source in Vietnam. So far, many applications of solar power have been implemented on small, medium, and large scales. In fact, the total capacity of current grid-connected solar power plants has exceeded the planned capacity by 2020 nearly 6 times. However, the studies of solar potential in Vietnam are still incomplete. The policies and mechanisms for developing solar power projects have received attention from the authorities but have not been really satisfactory. The infrastructure is still poor and the power system does not keep up with the development of modern grids. This paper reviewed the potential and actual implementation stage of photovoltaic projects in Vietnam. Moreover, the barriers and challenges of institution, technique, economy, and finance have been considered explicitly for the future development of solar energy in Vietnam.

Small wind turbines operating in low wind speed regions have not had any significant success. In addition, small wind speed regions occupy a large area of the world, so they represent a potential area for installing small wind turbines in the future. In this paper, a method to design an efficient airfoil for small wind turbines in low wind speed conditions using XFLR5 and CFD simulations is implemented. Because the impact of the airflow on the blade surface under low Re number conditions can change suddenly for small geometries, designing the airfoil shape to optimize the aerodynamic performance is essential. The tuning of the key geometric parameters using inversion techniques for better aerodynamic performance is presented in this study. A two-dimensional model was used to consider the airflow on the airfoil surface with differences in the angle of attack. The original S1010 airfoil was used to design a new airfoil for increasing the aerodynamic efficiency by using V6.57 XFLR5 software. Subsequently, the new VAST-EPU-S1010 airfoil model was adjusted to the maximum thickness and the maximum thickness position. It was simulated in low wind speed conditions of 4–6 m/s by a computational fluid dynamics simulation. The lift coefficient, drag coefficient, and CL/CD coefficient ratio were evaluated under the effect of the angle of attack and the maximum thickness by using the k-ε model. The simulation results show that the VAST-EPU-S1010 airfoil achieved the greatest aerodynamic efficiency at an angle of attack of 3°, a maximum thickness of 8%, and a maximum thickness position of 20.32%. The maximum value of CL/CD of the new airfoil at 6 m/s was higher than at 4 m/s by about 6.25%. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the physio-chemical properties of carrot peel powders obtained at four hot-air drying temperatures (50, 60, 70, and 80°C). The drying process ended when the materials achieved the moisture content of about 5-7%. The final products were subsequently analyzed for water activity, hydration indices, chemical composition, and color attributes to evaluate the influence of drying temperature on the quality of carrot peel powder. The results showed that the increment in drying temperature increased the hydration properties, the values of L*, and ΔE*, but reduced the contents of protein, and total carotenoids, as well as the values of a*, b*, and C*. In the range of hot-air conditions tested in this study, it is suggested to use an operating temperature of 50°C to minimize changes in the physico-chemical properties of the carrot peel powder. This is a preliminary study to optimize the drying conditions to produce carrot peel powder with high physico-chemical properties. Further studies will focus on investigating the effect of carrot peel powder on the performance of laying chickens. [ABSTRACT FROM AUTHOR]

Two new guaiane sesquiterpene lactones, vulgarolides A and B (1 and 2), were isolated from Artemisia vulgaris aerial parts using various chromatographic separations. The structure elucidation was performed by combination of spectroscopic experiments including 1D and 2D NMR, HR ESI MS, and CD. Their in vitro cytotoxic activities against five human cancer cell lines were also evaluated using SRB method. [ABSTRACT FROM AUTHOR]