Analyzing the investments strategies for renewable energies based on multi-criteria decision model

The purpose of this study is to determine appropriate innovative strategies for the renewable energy investments. For this purpose, a hybrid multi-criteria decision-making (MCDM) model is proposed based on interval type-2 (IT2) fuzzy sets and alpha cut levels. Within this context, hesitant IT2 fuzzy DEMATEL-Based Analytic Network Process (DANP) with alpha cut levels is applied for weighting the customer requirements. Moreover, hesitant IT2 fuzzy technique for order preference by similarity to ideal solution (TOPSIS) with alpha cut levels is used for ranking the TRIZ-based strategies priorities of renewable energy investments based on house of quality technique. These strategies are also ranked with hesitant IT2 fuzzy Vise Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR) approach to make a comparative evaluation. The results illustrate that ease of access and security are among the most prominent factors of customer requirements for renewable energy investments. It is also identified that innovative technical requirement entitled cushion in advance has the best choice for the sustainable renewable energy projects. Furthermore, the results of proposed model using hesitant IT2 fuzzy DANP and hesitant IT2 fuzzy TOPSIS are identical for the different levels of alpha cut. In addition, it is also defined that the results of hesitant IT2 fuzzy TOPSIS and hesitant IT2 fuzzy VIKOR are quite coherent. This is a clear evidence that the proposed model is coherent and could provide comprehensive results for the future studies. It is strongly recommended that a detailed analysis is required to identify the risks in renewable energy investment projects. Hence, necessary actions can be taken appropriately so that it can be possible to prevent problems before they grow.National Natural Science Foundation of China (NSFC) ; Humanities and Social Sciences Foundation of the Ministry of Education (MOE) in China ; FAFU Foundation for Distinguished Young Scholar

On the performance of the adaptive EWMA chart for monitoring time between events

International audienc

Modified One-Sided EWMA Charts without- and with Variable Sampling Intervals for Monitoring a Normal Process

Much research has been conducted on two-sided Exponentially Weighted Moving Average (EWMA) control charts, while less work has been devoted to the one-sided EWMA charts. Traditional one-sided EWMA charts involve resetting the EWMA statistic to the target whenever it falls below or above the target, or truncating the observations above or below the target and further applying the EWMA statistic to the truncated samples. In order to further improve the performance of traditional one-sided EWMA mean (X¯) charts, this paper studies the performance of the Modified One-sided EWMA (MOEWMA) X¯ charts to monitor a normally distributed process. The Monte-Carlo simulation method is used to obtain the zero- and steady-state Run Length (RL) properties of the proposed control charts. Through extensive simulations and comparisons with other charts, it is shown that the proposed MOEWMA X¯ charts compare favorably with some existing competing charts. Moreover, by attaching the variable sampling intervals (VSI) feature to the MOEWMA X¯ charts, it is shown that the VSI MOEWMA charts outperform the corresponding charts without the VSI feature. Finally, a real data example from manufacturing process shows the implementation of the proposed one-sided charts

Kinetic Research on the Curing Reaction of Hydroxyl-Terminated Polybutadiene Based Polyurethane Binder System via FT-IR Measurements

Polyurethane binder systems based on hydroxyl-terminated polybutadiene (HTPB) possess several superior properties such as superior adhesion, high solid-loading capacity, outstanding mechanical performance, etc. They have been widely used in coatings and adhesives as well as in medical and military industries. The cure reaction between hydroxyl-terminated polybutadiene (HTPB) and diisocyanates plays a key role in the properties of final products as well as the adjustment of process parameters. FT-IR spectroscopy is applied to investigate the kinetics of the curing reaction of HTPB and isophorone diisocyanate (IPDI) in the presence of a low toxic and low viscosity catalyst, stannous isooctoate (TECH). The concentrations of the isocyanate groups (NCO) characterized by FT-IR during the cure reaction with respect to time were recorded at different temperatures and at constant stoichiometric ratio Rn[NCO]/n[OH] = 1.0. The kinetic parameters, i.e., activation energy (Ea), pre-exponential factor (A), activation enthalpy (ΔH) and activation entropy (ΔS) were determined. In addition, the curing process and mechanism of the HTPB-IPDI reaction are discussed

Cord Blood Levels of Angiopoietin-Like 7 (ANGPTL7) in Preterm Infants

Objective. ANGPTL7 is a member of the angiogenin-like protein family. Compared to other members, ANGPTL7 is the least known. Recent studies have explored the relationship between ANGPTL7 and multiple pathological processes and diseases. However, there is no research about ANGPTL7 in neonates. This study was designed to investigate the concentration of ANGPTL7 in cord blood of preterm infants. Method. Singleton infants born in November 2017 to June 2019 in the study hospital were enrolled in the study. Maternal and neonatal clinical data were collected. ANGPTL7 levels in cord blood and serum on the third day after birth were measured by an enzyme-linked immunosorbent assay. Result. A total of 182 infants were enrolled in this study. Patients were categorized into two groups by gestational age (102 preterm, 80 full-term). ANGPTL7 levels in preterm infants were significantly higher than that in full-term babies (t=15.4, P<0.001). In multiple line regression analysis, ANGPTL7 levels independently correlated with gestational age (β=−0.556, P<0.001). There is also no correlation between preterm outcomes and ANGPTL7 levels. Cord blood levels of ANGPTL7 were significantly higher than those in serum on the third day after birth (t=13.88, P<0.001). Conclusion. Cord blood ANGPTL7 levels are higher in preterm infants than full-term babies. The levels are independently influenced by gestational ages and attenuated significantly after birth. The underlying mechanism needs to be further studied