Flowfield-dependent variant method for moving-boundary problems

A novel numerical scheme using the combination of flowfield-dependent variation method and arbitrary Lagrangian–Eulerian method is developed. This method is a mixed explicit–implicit numerical scheme, and its implicitness is dependent on the physical properties of the flowfield. The scheme is discretized using the finite-volume method to give flexibility in dealing with complicated geometries. The formulation itself yields a sparse matrix, which can be solved by using any iterative algorithm. Several benchmark problems in two-dimensional inviscid and viscous flow have been selected to validate the method. Good agreement with available experimental and numerical data in the literature has been obtained, thus showing its promising application in complex fluid–structure interaction problems

The Mediation Effect of Trusting Beliefs on the Relationship Between Expectation-Confirmation and Satisfaction with the Usage of Online Product Recommendation

Online Product Recommendations (OPRs) are increasingly available to onlinecustomers as a value-added self-service in evaluating and choosing a product.Research has highlighted several advantages that customers can gain from usingOPRs. However, the realization of these advantages depends on whether and towhat extent customers embrace and fully utilise them. The relatively low OPR USAgerate indicates that customers have not yet developed trust in OPRs’ performance.Past studies also have established that satisfaction is a valid measure of systemperformance and a consistent significant determinant of users’ continuous systemusage. Therefore, this study aimed to examine the mediation effect of trustingbeliefs on the relationship between expectation-confirmation and satisfaction. Theproposed research model is tested using data collected via an online survey from626 existing users of OPRs. The empirical results revealed that social-psychologicalbeliefs (perceived confirmation and trust) are significant contributors to customersatisfaction with OPRs. Additionally, trusting beliefs partially mediate the impactof perceived confirmation on customer satisfaction. Moreover, this study validatesthe extensions of the interpersonal trust construct to trust in OPRs and examinesthe nomological validity of trust in terms of competence, benevolence, andintegrity. The findings provide a number of theoretical and practical implications.&nbsp

Uncertainties in Global Warming Temperature-Trend and Their Impacts on Agricultural Production: an Econometric Evaluation

IndonesianMakalah ini membahas kecenderungan dampak pemanasan global yang terjadi akhir-akhir ini. Estimasi dilakukan dengan parameter fraksional dari catatan relatif panjang menggunakan tehnik outlier aditif sebagai pengamatan bebas yang dihasilkan di atmosfer karena pemanasan global. Selanjutnya penelitian ini mengamati secara empiris dampak pemanasan global terhadap aspek tertentu produksi pertanian global. Berdasarkan simulasi Monte Carlo, proses menghasilkan data diterapkan dimana outlier aditif dihasilkan melalui cara discrete atau tidak kontinyu. Hasil observasi menunjukkan bahwa outlier aditif mempengaruhi bias dan MSE parameter fraksional estimasi. Ukuran outlier aditif dalam proses menghasilkan data juga memiliki pengaruh penting terhadap parameter farksional estimasi yang tergantung pada nilai parameter fraksional yang sebenarnya. Hasilnya menunjukkan variabilitas non tren atau siklus alami yang dipengaruhi oleh proses stokastik dalam hal sifat Perubahan iklim dengan observasi bebas (outlier) yang menghasilkan outcome berlawanan dari ketidakpastian yang intensif terhadap tren data temperatur dunia pada kondisi riil. Hasil pengamatan empiris menyimpulkan bahwa pada akhir abad 21 secara meyakinkan pemanasan global akan mempunyai dampak negatif terhadap agregat produksi pertanian global dan dampaknya bisa sangat parah jika manfaat fertilizasi karbon (peningkatan hasil dalam lingkungan yang kaya karbon) tidak tampak, terutama jika kelangkaan air membatasi irigasi. Lagi pula, jika pemasan global tidak berhenti pada tahun 2080, tetapi temperatur global terus meningkat pada abad 22, kegagalan produksi pertanian bisa semakin parah. Studi ini juga menunjukkan bahwa akumulasi pengaruh produksi pertanian kemungkinan lebih serius bagi negara berkembang dengan kerugian terbesar di Afrika, Amerika Latin, dan India. EnglishThis paper primarily attempts to detect the trend in the present upshots of global warming temperature data. It has been done through the estimation of the long memory fractional parameter using a simulation technique in the presence of additive outliers which stands as wild observations generated in the atmosphere due to global warming. Then, the study investigates empirically the impact of global warming on the particular aspect of global agricultural production. Based on Monte Carlo simulations, a data generating process is applied where additive outliers are generated in a discrete way. Observed facts reveal that additive outliers affect the bias and the MSE of the estimated fractional parameter. The size of the additive outliers in data generating process has also important effects on the estimated fractional parameter depending on the value of true fractional parameter. The result exhibits a non-trend or a natural cyclical variability influenced by a stochastic process in the case of climate change behavior with wild observations (outliers) that produce a contradictory outcome of profound uncertainties against the case of true world temperature data trend. The results of empirical investigations assert that in the late 21st century unabated global warming would have a negative impact on global agricultural production in the aggregate and the impact could be severe if carbon fertilization benefits (enhancements of yields in a carbon-rich environment) do not materialize, especially if water scarcity limits irrigation. In addition, if warming would not halt in the 2080s, but would continue on a path toward still higher global temperatures in the 22nd century, agricultural damage could be more severe. The study also shows that the composition of agricultural effects is likely to be seriously unfavorable to developing countries with the most severe losses in Africa, Latin America and India

An Investigation of Information System Utilization in Small Sized Hotels in Kedah.

The rapid growth with the using of the IS becomes more necessary in the various fields. Utilizes the Information System in Small Sized Hotels in Kedah, these hotels will be able to make integrates and utilize the information system during the hotel progress which support the manager with the appropriate facilities, the research illustrated the main problems that facing these hotels, most of these hotels require to integrate and utilize some features to keep the hotel progress. Utilizes the Information System in Small Sized Hotels in Kedah obtained easy way to access the enquire information about the strategy of the small hotels that need to follow. Finally, this research suggested to the small hotels to enhancing there IS capabilities of in future

Ash (Fraxinus excelsior) seed quality in relation to seed deterioration under accelerated aging conditions

This study was conducted to evaluate the response of ash (Fraxinus excelsior) seeds under accelerated aging test. The accelerated aging test was carried out at three different temperatures: 41, 43 and 45°C with four duration periods of 48, 72, 96, 144 and a relative humidity of 100%. The two seed lots of F. excelsior were subjected to tests of their quality including standard germination, vigor index, seedling growth and seedling dry weight. A completely randomized factorial design with four replications was used. Results indicated that, old seeds were more sensitive to accelerated aging than new seeds. Seeds of both lots had a reduction of viability and vigor after accelerated aging at 41°C for 96 h, 43 and 45°C for 72 to 144 h. Germination, vigor index, seedling growth and seedling dry weight showed a greater response to accelerated aging.Key words: Fraxinus excelsior, accelerated aging, germination, seed vigor, seedling growth rates

Levels of mercury and arsenic contamination in popular fish and shrimp brands consumed in Saudi Arabia

ABSTRACT. Fish and shrimp are public sources of healthy protein for a large fragment of the Saudi population. Therefore, the present work was conducted to assess the level of possible arsenic (As) and mercury (Hg)          con­tamination of these sea foods. Eight species of fish and two species of shrimp were collected from the local mar­kets of Eastern Province, Saudi Arabia. Mercury and arsenic concentration of samples was determined by hydride generation atomic absorption spectrometry (HG-AAS). Highest average concentration of total Hg was found in Siganus canaliculatus (0.54 ± 0.06 µg/g) while the lowest level was detected in Lethrinus miniatus (0.24 ± 0.07 µg/g). For shrimp species, the levels varied from 0.13 to 0.91 µg/g for mercury and 0.19 to 0.53 µg/g for arsenic. The rank order of shrimp species based upon mercury level was Penaeus semisulcatus > Penaeus indicus; whereas based upon arsenic level it was almost similar. Mean levels of both Hg and As in all the species studied are lower than the limits set by international health agencies; 0.550 µg/g for mercury and 6.0 µg/g for arsenic.               KEY WORDS: Arabian Gulf, Fish, Shrimp, Arsenic, Mercury Bull. Chem. Soc. Ethiop. 2019, 33(3), 573-578.      DOI: https://dx.doi.org/10.4314/bcse.v33i3.1