Application of natural fibre composite in the aviation industry: a review

The evolution in aviation industry continues to evolve in this current era. The aviation industry is engaged in the research, development and manufacturing of flight vehicles. The critical item such as the propulsion systems, avionics system, operating and maintenance of flight vehicle are rigorously improved year by year. The interior components of aircraft are gaining serious attention in replacing the synthetic fibre with natural fibre composite material. The researchers conducted are mainly for civil, security and transportation. However, the focus on aircraft interior still immature and need further investigation. Therefore, this paper is reviewing the potential of natural fibre in the aviation industry

ON DIRECT PRODUCT pure − 1 − 2 − 3 SUBGROUPS IN ABELIAN GROUP Gn×Gm

In this paper, we shall define new subgroups which are called pure−1−2−3 in abelian groups Gn×Gm for all n,m∈N which are a family of pure subgroups. In[1],[2]H.M.A.Abdullah  gave the some general properties of pure− 1−2−3 in abelian group G, but here, we shall prove more than properties on this subgroups in ModGn×Gm, which are not valid for pure subgroups

Testing extreme value copulas to estimate the quantile

We generalize the test proposed by Kojadinovic, Segers and Yan which is used for testing whether the data belongs to the family of extreme value copulas. We prove that the generalized test can be applied whatever the alternative hypothesis. We also study the effect of using different extreme value copulas in the context of risk estimation. To measure the risk we use a quantile. Our results have been motivated by a bivariate sample of losses from a real database of auto insurance claims

Testing extreme value copulas to estimate the quantile

We generalize the test proposed by Kojadinovic, Segers and Yan which is used for testing whether the data belongs to the family of extreme value copulas. We prove that the generalized test can be applied whatever the alternative hypothesis. We also study the effect of using different extreme value copulas in the context of risk estimation. To measure the risk we use a quantile. Our results have been motivated by a bivariate sample of losses from a real database of auto Insurance claims

STUDI PERHITUNGAN KOEFISIEN REAKTIVITAS TEMPERATUR SMALL PEBBLE BED REACTOR BERBAHAN BAKAR TIPE WALLPAPER MENGGUNAKAN PROGRAM TRANSPORT MONTE CARLO MCNPX 2.6.0

Konsep bahan bakar wallpaper dikembangkan untuk menurunkan temperatur puncak bahan bakar dengan memberikan modifikasi yang baru pada bahan bakar pebble dimana material grafit dengan radius tertentu ditempatkan di pusat bahan bakar sehingga zona bahan bakar hanya tersebar di bagian permukaan dalam pebble. Penelitian ini difokuskan pada perhitungan dan analisis parameter neutronika reaktor yang disebut koefisien reaktivitas temperatur teras. Reaktor pebble bed HTR-10 dipilih sebagai objek reaktor dalam penelitian. Seluruh perhitungan dilakukan dengan menggunakan program transport Monte Carlo MCNPX 2.6.0 dan pustaka data nuklir energi kontinu ENDF/B-VI. Dalam studi ini, koefisien reaktivitas temperatur dihitung dalam tiga tahap perhitungan, yakni perhitungan koefisien reaktivitas temperatur bahan bakar, koefisien reaktivitas temperatur moderator dan kombinasi koefisien reaktivitas temperatur bahan bakar dan moderator. Hasil analisis memperlihatkan bahwa kenaikan temperatur bahan bakar menunjukkan nilai koefisien reaktivitas yang negatif pada fraksi packing partikel 5.5% hingga 20%, sedangkan pada fraksi packing 25% dan 30% koefisien reaktivitas temperatur bernilai positif. Pada tahap perhitungan koefisien reaktivitas temperatur moderator, seluruh perhitungan menunjukkan nilai yang negatif untuk seluruh fraksi packing yang dipertimbangkan dan terus mengalami penurunan seiring dengan meningkatnya temperatur moderator. Untuk perhitungan kombinasi koefisien reaktivitas, fraksi packing partikel 5.5% hingga 20% memperlihatkan penurunan nilai koefisien reaktivitas sedangkan pada fraksi packing partikel 25% dan 30% menunjukkan nilai koefisien reaktivitas yang meningkat seiring dengan bertambahnya temperatur bahan bakar dan moderator. Meskipun demikian, secara umum operasi reaktor berada pada kondisi aman ditinjau dari hasil perhitungan secara keseluruhan yang memperlihatkan kondisi cukup baik dengan nilai koefisien reaktivitas temperatur yang negatif untuk seluruh kenaikan temperatur bahan bakar dan moderator

Synthesis and mesophase behaviour of Benzylidene-based molecules containing two Azomethine units

The research work involves the synthesis and characterization of intermediates 4-heptyloxybenzaldehyde (1) and 4-dodecyloxybenzaldehyde (2). Five compounds with two Schiff base linking units were further synthesized by condensation reaction using aldehyde and 1, 4-phenylenediamine. These compounds include N, N'-dibenzyliden-benzen-1, 4-diamine (3); N-benzyliden-N'-(4-chlorobenzyliden) benzen-1, 4-diamine (4); N-benzyliden-N'-(4-methoxybenzyliden) benzen-1, 4-diamine (5); N-benzyliden-N'-(4-heptyloxybenzyliden) benzen-1, 4-diamine (6) and N-benzyliden-N'-(4-dodecyloxybenzyliden) benzen-1, 4-diamine (7). These compounds were characterized using Fourier-Transform Infrared (FTIR), 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy and CHN elemental analysis. Polarized Optical Microscope (POM) was used to detect liquid crystal mesophase(s) and their thermal behaviour was measured using Differential Scanning Calorimetry (DSC). Compounds 4, 6 and 7 showed the nematic phases, while compounds 3 and 5 were found to be non-mesogenic without any liquid crystal properties