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The cubic equation of state (CEoS) is a powerful method for calculation of (vapor + liquid) equilibrium (VLE) in polymer solutions. Using CEoS for both the vapor and liquid phases allows one to calculate the non‐ideality of polymer solutions based on a single EoS approach. In this research, vapor–liquid equilibria calculations of polyvinyl acetate (PVAc)/solvent solutions were performed. In this approach, eight models containing PRSV and SRK CEoS separately combined with four mixing rules namely vdW1, vdW2, Wong–Sandler (WS), and Zhong–Masuoka (ZM) were applied to calculations of bubble point pressure. For the better prediction, the adjustable binary interaction parameters existing in any mixing rule were optimized. The results were very acceptable and satisfactory. Absolute average deviations (%AAD) between predicted results and experimental bubble point pressure data were calculated and presented. The capability of two cubic equations of state had a good agreement with experimental data and predict the correct type of phase behavior in all cases, but the performance of the PRSV + vdW2 was more reliable than the other models with 2.65% in AAD for total of solution systems. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40651.  相似文献   
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ABSTRACT

In modern cities, life is primarily formed in interaction with various environmental, social, economic, infrastructural, hygienic, safety, political and cultural conditions. Urban quality of life (UQoL) is the result of such interactions. In general, both objective and subjective approaches are used in the study and modelling of UQoL. So far the studies have been conducted in forms of social and large-scale geographical studies mainly ignoring spatial differences of quality of life (QoL) in complicated urban environments. Moreover, QoL as one of the attributes of geographical environment is a dynamic and variable concept which has received little attention. Spatiotemporal modelling of this concept can contribute to monitoring the UQoL and planning for its improvement. The current study aims to develop a method for spatiotemporal modelling of UQoL. For this purpose, multi criteria decision making (MCDM) method and fuzzy logic are used. Moreover, given the variability of some indicators, temporal modelling of UQoL was conducted based on snapshot method in seasonal scale. In order to evaluate the proposed procedure, modelling of QoL was done at urban blocks scale in regions 3, 6, and 11 of Tehran, Iran. The results show the existence of a fairly regular pattern as an increase in desirability of UQoL from south to north of the area. The seasonal changes of UQoL show the improvement of environmental condition in spring and autumn compared to winter and summer. The result of sensitivity analysis shows the reliability of the modelling results. Since the effect of inputs on the fuzzy gamma output (2.5%) are less than the corresponding amount in VIKOR-fuzzy method (48%), it can be concluded that the output of fuzzy-gamma is more reliable.  相似文献   
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This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of ginger intake on weight loss, glycemic control and lipid profiles among overweight and obese subjects. We searched the following databases through November 2017: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The relevant data were extracted and assessed for quality of the studies according to the Cochrane risk of bias tool. Data were pooled using the inverse variance method and expressed as Standardized Mean Difference (SMD) with 95% Confidence Intervals (95% CI). Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I2). Overall, 14 studies were included in the meta-analyses. Fourteen RCTs with 473 subjects were included in our meta-analysis. The results indicated that the supplementation with ginger significantly decreased body weight (BW) (SMD ?0.66; 95% CI, ?1.31, ?0.01; P = 0.04), waist-to-hip ratio (WHR) (SMD ?0.49; 95% CI, ?0.82, ?0.17; P = 0.003), hip ratio (HR) (SMD ?0.42; 95% CI, ?0.77, ?0.08; P = 0.01), fasting glucose (SMD ?0.68; 95% CI, ?1.23, ?0.05; P = 0.03) and insulin resistance index (HOMA-IR) (SMD ?1.67; 95% CI, ?2.86, ?0.48; P = 0.006), and significantly increased HDL-cholesterol levels (SMD 0.40; 95% CI, 0.10, 0.70; P = 0.009). We found no detrimental effect of ginger on body mass index (BMI) (SMD ?0.65; 95% CI, ?1.36, 0.06; P = 0.074), insulin (SMD ?0.54; 95% CI, ?1.43, 0.35; P = 0.23), triglycerides (SMD ?0.27; 95% CI, ?0.71, 0.18; P = 0.24), total- (SMD ?0.20; 95% CI, ?0.58, 0.18; P = 0.30) and LDL-cholesterol (SMD ?0.13; 95% CI, ?0.51, 0.24; P = 0.48). Overall, the current meta-analysis demonstrated that ginger intake reduced BW, WHR, HR, fasting glucose and HOMA-IR, and increased HDL-cholesterol, but did not affect insulin, BMI, triglycerides, total- and LDL-cholesterol levels.  相似文献   
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Optimal Inter-Basin Water Allocation Using Crisp and Fuzzy Shapley Games   总被引:3,自引:3,他引:0  
In recent years, uneven distribution of available water resources as well as increasing water demands and overexploiting the water resources have brought severe need for transferring water from basins having sufficient water to basins facing water shortages. Therefore, optimal allocation of shared water resources in water transfer projects, considering the utilities of different stakeholders, physical limitations of the system and socioeconomic criteria is an important task. In this paper, a new methodology based on crisp and fuzzy Shapley games is developed for optimal allocation of inter-basin water resources. In the proposed methodology, initial water allocations are obtained using an optimization model considering an equity criterion. In the second step, the stakeholders form crisp coalitions to increase the total net benefit of the system as well as their own benefits and a crisp Shapley Value game is used to reallocate the benefits produced in the crisp coalitions. Lastly, to provide maximum total net benefit, fuzzy coalitions are constituted and the participation rates of water users to fuzzy coalitions are optimized. Then, the total net benefit is reallocated to water users in a rational and equitable way using Fuzzy Shapley Value game. The effectiveness of this method is examined by applying it to a large scale case study of water transfer from the Karoon river basin in southern Iran to the Rafsanjan plain in central Iran.  相似文献   
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In this paper, a seasonal multi-product multi-period inventory control problem is modeled in which the inventory costs are obtained under inflation and all-unit discount policy. Furthermore, the products are delivered in boxes of known number of items, and in case of shortage, a fraction of demand is considered backorder and a fraction lost sale. Besides, the total storage space and total available budget are limited. The objective is to find the optimal number of boxes of the products in different periods to minimize the total inventory cost (including ordering, holding, shortage, and purchasing costs). Since the integer nonlinear model of the problem is hard to solve using exact methods, a particle swarm optimization (PSO) algorithm is proposed to find a near-optimal solution. Since there is no bench mark available in the literature to justify and validate the results, a genetic algorithm is presented as well. In order to compare the performances of the two algorithms in terms of the fitness function and the required CPU time, they are first tuned using the Taguchi approach, in which a metric called “smaller is better” is used to model the response variable. Then, some numerical examples are provided to demonstrate the application and to validate the results obtained. The results show that, while both algorithms have statistically similar performances, PSO tends to be the better algorithm in almost all problems.  相似文献   
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Water Resources Management - In this paper, a new methodology is developed for urban runoff management based on global sensitivity analysis of the storm water management model (SWMM) considering...  相似文献   
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Water Resources Management - In this paper, daily and monthly runoff discharge forecasts are improved by developing an ensemble model based on the Bayesian maximum entropy (BME), which integrates...  相似文献   
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