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"This book was written to facilitate column sizing and reinforcement design for structural engineers. It arranges the design data in a clearly structured manner, and provides quick and easy ways for engineers to compare the feasibility of multiple alternatives (various column sizes and reinforcement configurations). With the help of this book, engineers can rapidly produce outputs for architects, which the latter can incorporate into their architectural layout plans. These outputs can also benefit quantity surveyors, especially for costing purposes, and help avoid careless design errors.​;;"

"One method of increasing the durability of cylindrical concrete columns in aggressive surroundings is by providing a PVC skin around the columns. Beside protection added mechanical benefits have been investigated in this study. Results of this endeavor are reported in this paper. One hundred and fourteen specimens were prepared utilizing prepacked aggregate concrete (PA-Concrete), Consisting of andesite coarse aggregates and cement grout with 30% fly ash as partial cement replacement. Cylindrical specimens with varying length over diameter ratios (LID) and ages have been tested for their strength and ductilities. Results have shown the prevalence of beneficial composite behavior in PVC-confined specimens. Strength increases of 30% to 50% above those of unconfined specimens have been observed. Displacement ductilities lA > 7 have been derived, implying an increase of more than 8 times of those of unconfined specimens. Strains ductilities /l. > 2.4 and residual strength ratios R> 0.52Rp have been observed. Results indicate that strength increase with increasing ages while ductilities decrease with increasing un values. Toward the end of this paper, attempt is made to explain the mechanics of confinement in generating high load capacities of PVC protected columns."

"ABSTRACTHelium is an abundant material with unique properties such as noble gas properties and very light compound. With many industrial and research purpose, Helium demand in the global market is rising. Natural gas is the richest source of Helium that can be extracted, with only 0.1 2 composition in the natural gas. This concentration of helium in the natural gas require an energy intensive process such as the use of low temperature distillation although some new emerging technologies such as membrane and adsorption technologies. Evaluation process using conventional two stage distillation column to recover helium and LNG is assessed and analysed on this paper to see if the project is feasible. The process design of distillation column simulated in Aspen HYSYS to assess the energy correlated in each equipment and their parameters studies affecting the production. With the assumption of production specification are out of the context, the helium extraction process requires significant amount of cooling energy with high economic capital. This comes to the fact with the process operation operates in 100 to almost 200oC for refrigeration process also equipped with expensive equipment such as distillation columns and heat exchangers.

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ABSTRAKHelium merupakan unsur yang berlimpah di alam semesta dengan berbagai sifat unik seperti gas mulia dan berat jenis yang sangat ringan. Dengan berbagai fungsi di industri maupun fungsi akademis, kebutuhan gas helium di pasar dunia menunjukan trend meningkat. Gas alam merupakan sumber utama dari Helium yang menunjukan sumber yang layak, dengan konsentrasi hanya 0.1 - 2 fraksi di gas alam sudah dapat dianggap menjadi gas alam yang kaya akan Helium. Oleh karena itu, extraksi helium dari gas alam membutuhkan operasi energi yang tinggi seperti penggunaan kolom distilasi pada suhu rendah, meskipun sudah terdapat teknologi terbaru seperti penggunaan membran dan teknologi absorbsi. Evaluasi menggunakan kolom distilasi dua tahap pada suhu rendah akan diperdalami guna memberikan model tersebut memberikan kelayakan dalam mengekstraksi Helium. Model ini disimulasikan dengan Aspen HYSYS dalam mengevaluasi konsumpsi energi dari sistem pada setiap peralatan dan juga mempelajari variabel yang mempengaruhi dalam operasi. Dengan asumsi pengkondisian pada produk diluar dari cakupan, ekstraksi helium menggunakan energi pendingin dengan jumlah yang signifikan dan juga harga capital yang tinggi. Ini disebabkan dengan fakta operasi dari simulasi dilakukan pada suhu rentang -100oC sampai dengan -200oC untuk merefrigerasi gas alam dan juga penggunaan peralatan yang menarik biaya besar seperti kolom distilasi dan beberapa alat penukar panas."