Deep learning approach and topic modelling for forecasting tourist arrivals

Online review data attracts the attention of researchers and practitioners in various fields, but its application in tourism is still limited. The social media data can finely reflect tourist arrivals forecasting. Accurate prediction of tourist arrivals is essential for tourism decision-makers. Although current studies have exploited deep learning and internet data (especially search engine data) to anticipate tourism demand more precisely, few have examined the viability of using social media data and deep learning algorithms to predict tourism demand. This study aims to find the key topics extracted from online reviews and integrate them into the deep learning model to forecast tourism demand. We present a novel forecasting model based on TripAdvisor reviews. Latent topics and their associated keywords are captured from reviews through Latent Dirichlet Allocation (LDA), These generated features are then employed as an additional feature into the deep learning (DL) algorithm to forecast the monthly tourist arrivals to Hong Kong from USA. We used machine learning models, artificial neural networks (ANNs), support vector regression (SVR), and random forest (RF) as benchmark models. The empirical results show that the proposed forecasting model is more accurate than other models, which rely only on historical data. Furthermore, our findings indicate that integration of the topics extracted from social media reviews can enhance the prediction

A novel hybrid deep learning approachfor tourism demand forecasting

This paper proposes a new hybrid deep learning framework that combines search query data, autoencoders (AE) and stacked long-short term memory (staked LSTM) to enhance the accuracy of tourism demand prediction. We use data from Google Trends as an additional variable with the monthly tourist arrivals to Marrakech, Morocco. The AE is applied as a feature extraction procedure to dimension reduction, to extract valuable information and to mine the nonlinear information incorporated in data. The extracted features are fed into stacked LSTM to predict tourist arrivals. Experiments carried out to analyze performance in forecast results of proposed method compared to individual models, and different principal component analysis (PCA) based and AE based hybrid models. The experimental results show that the proposed framework outperforms other models

Bitter and sweet lupin (Lupinus albus L.) seeds and seed oils : a comparison study of their compositions and physicochemical properties

In this study, bitter and sweet lupin (Lupinus albus L.) seed oils (BLO and SLO) were extracted using the soxhlet extraction method. The physicochemical properties, fatty acid compositions, thermal properties, 1H NMR, FTIR and UV visible spectra of BLO and SLO were evaluated. In addition, the antioxidant properties of bitter and sweet lupin seeds and their oils were also studied. The results showed that the bitter and sweet lupin seeds consist of 8% and 12% of oil, respectively. BLO and SLO contained high concentration of oleic acid (46.28 and 48.72%), followed by linoleic acid (21.55 and 20.90%), linolenic acid (7.69 and 8.95%), and palmitic acid (7.39 and 7.5%). The total tocopherol content of BLO and SLO were 184.70 and 317.01 mg/100 g oil, respectively. TG/DTG curves showed that the process thermal decomposition of the oils occurs in four phases for SLO and three phases for BLO

Syndrome du canal carpien secondaire à une variété anatomique rare du nerf médian

Le syndrome du canal carpien représente l'un des motifs de consultation les plus fréquents en chirurgie de la main, son incidence annuelle est de 300 par 100.000 habitants et 80.000 interventions chirurgicales pour le syndrome du canal carpien sontréalisés chaque année en France. Dans la plupart des cas, le syndrome du canal carpien est idiopathique survenant sans qu'aucune cause puisse être identifiée, cependant en dehors de ces formes l'intrication de plusieurs mécanismes peuvent expliquer la relation cause à effet de cette pathologie. A travers cette observation nous allons essayer de mettre la lumière sur une association exceptionnelle d'un syndrome du canal carpien secondaire à une variété anatomique rare du nerf médian

Optimization and blends study of heterogeneous acid catalyst assisted esterification of palm oil industry by-product for biodiesel production

The optimum conditions to produce palm fatty acid distillate (PFAD)-derived-methyl esters via esterification have been demonstrated with the aid of the response surface methodology (RSM) with central composite rotatable design in the presence of heterogeneous acid catalyst. The effect of four reaction variables, reaction time (30–110 min), reaction temperature (30–70°C), catalyst concentration (1–3 wt.%) and methanol : PFAD molar ratio (3 : 1–11 : 1), were investigated. The reaction time had the most influence on the yield response, while the interaction between the reaction time and the catalyst concentration, with an F-value of 95.61, contributed the most to the esterification reaction. The model had an R2-value of 0.9855, suggesting a fit model, which gave a maximum yield of 95%. The fuel properties of produced PFAD methyl ester were appraised based on the acid value, iodine value, cloud and pour points, flash point, kinematic viscosity, density, ash and water contents and were compared with biodiesel EN 14214 and ASTM D-6751 standard limits. The PFAD methyl ester was further blended with petro-diesel from B0, B3, B5, B10, B20 and B100, on a volumetric basis. The blends were characterized by TGA, DTG and FTIR. With an acid value of 0.42 (mg KOH g−1), iodine value of 63 (g.I2/100 g), kinematic viscosity of 4.31 (mm2 s−1), the PFAD methyl ester has shown good fuel potential, as all of its fuel properties were within the permissible international standards for biodiesel

Electrodeposition of 4,4′-di-tert-butylbiphenyl peroxide from the anodic oxidation of p-tert-butylphenol in an alkaline acetonitrile solution

The electrogeneration of pure 4,4′-di-tert-butylbiphenyl peroxide as an electrodeposit could be achieved on a platinum electrode through the anodic oxidation of p-tert butylphenol in the presence of Lutidine, in addition to several soluble oligomers. The electrochemical and theoretical studies have shown that the favored coupling reaction corresponds to the O–O bond, albeit it is generally being considered unstable. Without the strong base, a mixture of trimer, tetramer and pentamer was deposited. The peroxide product presents a different electroactivity to that of the phenolic compound, with the appearance of a redox process involving cathodic and anodic symmetrical peaks at −0.10/0.15 V versus SCE, which indicates the preference of the polymer to adhere onto the electrode surface. The thermal degradation has also been analyzed. Quantum-chemical calculations reveal the reason for the oxygen–oxygen coupling.The authors would like to thank the Tunisian Ministry of Higher Education and Research for its financial support as well as the King Saud University for its funding through the Research Group Project No RGP-VPP-243. They would also like to thank the Spanish Ministry of Economy and Competitiveness for its financial support and the STIs for the ERDF funds (MAT2013-42007-P) and the Generalitat Valenciana (PROMETEO2013/ 038)

Characteristics of Chamaerops humilis L. var. humilis seed oil and study of the oxidative stability by blending with soybean oil

Herein we examine the characteristics of date seed oil extracted from Chamaerops humilis L. var. humilis seeds (HSO) cultivated in a gardening zone in Tunisia. Its physicochemical properties, fatty acid composition, and thermal and antioxidant properties were evaluated and compared with those of seed oil from another variety of Chamaerops humilis. The results showed that HSO possessed higher contents of oleic (44%) and linoleic (20%) acids than the other seed oil. The total tocopherol and tocotrienol content was 88 mg/100 g oil, where α-tocotrienol (64%) was the major isomer. The total phenolic (91 μg/g oil) and flavonoid contents (18 μg/g oil) of the HSO were determined, and its antioxidant capacities, measured in terms of ABTS and DPPH radical-scavenging capacities, were 210 µM TEAC/g DW and 4.3 mM TEAC/g DW, respectively. The oxidative stability index (OSI) of the oil was 16 h at 110 °C. Furthermore, the OSI of soybean oil was significantly enhanced upon blending with HSO. HSO exhibited higher thermal stability than the other oils and significantly different thermal behavior. The determination of fatty acid composition, physicochemical properties, bioactive content, oxidative stability, and thermal behavior of HSO demonstrated that this renewable resource can be used for edible purposes