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Portfolio Diversification Benefits of Cryptocurrencies and ASEAN-5 Stock Markets
Bakri Abdul KARIM,Aisyah ABDUL-RAHMAN,Josephine Yau Tan HWANG,Norlina KADRI 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.6
This paper examines the portfolio diversification benefits in the cryptocurrencies (Bitcoin, Ethereum, Ripple, Litecoin, Stellar and Dash) and ASEAN-5 stock markets (Malaysia, Indonesia, Singapore, Thailand and Philippines). Cointegration and Granger causality tests are used in this study for the period from August 2015 to October 2019. We found evidence of no cointegration among the cryptocurrencies. Thus, the cryptocurrencies market provides an opportunity for the potential benefits from portfolio diversification and hedging strategies. However, cointegration is found between cryptocurrencies and ASEAN-5 stock markets thus indicating limited portfolio diversification benefits in the long-run among these markets. In addition, the results also show that ASEAN-5 stock markets are going towards a greater integration among them which is in congruence with the previous studies. However, in the short-run, Granger causality tests show that Dash, Ethereum, Lite, Ripple and Stellar have no causality relationship with all ASEAN-5 stock markets and no causality is also found between Bitcoin and three of ASEAN-5 stock markets (Malaysia, Singapore and Philippines). Therefore, there still exists an opportunity for portfolio diversification between cryptocurrencies and ASEAN-5 stock markets in the short-run. The findings of this study suggest that crypto-investors, international investors and fund managers can diversify their investments in both cryptocurrencies and the ASEAN-5 stock markets.
M’hamed Adjoudj,Karim Ezziane,El Hadj Kadri,Hamza Soualhi 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.7
In the manufacture of mortar or concrete, the mixing water fills the interstitial voids between the solid particles of cement and thevolume of the resulting paste should be more than sufficient to fill the voids between the fine and coarse aggregates. So we shouldhave enough water to cover all the fine particles and enough paste to cover all aggregates. Therefore, it can be assumed that bothWater Film Thickness (WFT) and paste film thickness have major effects on the rheology of the mortar. In this work, we try to applythis approach to understand the rheological properties of mortars containing various amount of Silica Fume (SF) with two types ofsuperplasticizer using rheometer apparatus and mini cone test. The results show that the rheological behavior is governed by waterfilm thickness and the dosage of superplasticizer. However, for high dosages water film thickness remains the only factor governingthe behavior. In addition, the mixture compactness increases significantly when adjuvanted with efficient superplasticizer.
Djezzar, Mahdjoub,Ezziane, Karim,Kadri, Abdelkader,Kadri, El-Hadj Techno-Press 2018 Advances in concrete construction Vol.6 No.3
The objective of this study was to evaluate the influence of silica fume (SF) on the hydration heat and compressive strength of concrete. Portland cement with w/(c+sf) ratios varying between 0.25 to 0.45 was substituted by 10%, 20% and 30% of SF by mass. A superplasticizer was used to maintain a fluid consistency of the concrete. The heat of hydration was monitored continuously by a semi-adiabatic calorimetric method for 10 days at $20^{\circ}C$. Compressive strengths are tested for each mixture until age of 180 days. The results show that silica fume considerably influences the evolution and the ultimate values of the compressive strengths as well as the hydration heat especially for 10% rate. The w/b ratio has a considerable effect where its decrease modifies compressive strength and hydration heat more than silica fume. The correlation of the obtained results allows deducing of ultimate properties as well as the ages to reach half of their values. The correlation coefficients are close to unity and reflect the judicious choice of these relationships to be used to predict compressive strength and hydration heat.
Didouche, Zahia,Ezziane, Karim,Kadri, El-Hadj Techno-Press 2018 Advances in concrete construction Vol.6 No.6
The use of some superplasticizers in the production of mortar or concrete influences the hydration kinetic and the amount of total heat. This results in a modification of some properties, namely mortar workability, mechanical strength and durability. Three superplasticizers were used; a polynaphthalenesulfonate (PNS), a melamine resin (PMS) and a polycarboxylate (PC). They have been incorporated into various amount in a standardized mortar based on limestone cement. The aim of this study was to evaluate the rheological, mechanical and Calorimeters properties of this mortar. This will select the most compatible product and more able to be used depending on the climate of the country and the cement used. The PNS is incompatible with this type of cement registering a decrease of strength but the PMS and the PC modify the kinetics of hydration with significant heat generation and improved mechanical strength. The measured heat flow is significantly influenced by the type and dosage of superplasticizer especially for low dosage. Hydration heat and compressive strength of the different mixtures can be evaluated by determining their ultimate values and ages to reach these values where the correlation coefficients are very satisfactory.