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"Balok pracetak berongga atau hollow core beam (HCB) merupakan pengembangan atau inovasi dari Hollow-Core Slab (HCS). Balok pracetak berongga bukanlah produk baru dalam dunia konstruksi, karena sudah digunakan untuk girder pada jembatan dan balok pada bangunan-bangunan tinggi. Rongga pada balok ditujukan untuk mengurangi berat balok untuk kemudahan mobilisasi pelaksanaan konstruksi di lapangan, namun pada akhirnya rongga tersebut dicor setelah ditempatkan, hanya karena pertimbangan kemudahan pelaksanaan. Perlu dilakukan penelitian untuk mencari metode pelaksanaan yang mudah agar rongga tersebut tetap dipertahankan sehingga menghemat volume beton yang digunakan di proyek konstruksi.Studi eksperimental untuk mencari metode pelaksanaan yang mudah serta mempelajari pengaruh rongga pada balok pracetak terhadap kekuatan lentur telah dilakukan dengan enam (6) benda uji berukuran 200 x 400 x 3850 mm, serta menggunakan dua mutu beton yang berbeda, yaitu K-300 dan K-400. Four point loading test dipilih untuk melihat perilaku balok. Tiga (3) spesimen balok beton bertulang K-400 solid dengan ukuran yang sama juga dites sebagai balok pembanding. Hasil pengujian dianalisa berdasarkan grafik hubungan antara beban – lendutan, grafik hubungan antara momen - putaran sudut di tengah bentang, serta pola retak yang terjadi pada masing-masing spesimen.Hasil pengujian menunjukkan balok berongga K-400 memiliki kekuatan lentur 0.98 kali kekuatan lentur balok solid dengan mutu beton yang sama. Balok berongga K-300, memiliki kekuatan lentur 0.965 kali kekuatan lentur balok berongga dengan mutu beton K-400. Penelitian ini juga memberikan gambaran proses pembuatan balok berongga cast in site (cor setempat) yang dapat diterapkan dilapangan.

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Precast Hollow-Core Beam (HCB) is an innovation of Hollow-Core Slab, and not a new product in the construction. It has been used as girders of bridge and beams in high-rise buildings. The hollow is intended to reduce beam weight for ease of mobilization. Unfortunately, due to easiness of construction method, that hollow is casted after being placed. Research has been done to find an easy method of construction to maintain that hollow so that concrete volume can be reduced.

Experimental studies have been conducted. There are six (6) reinforced concrete beams of 200 x 400 x 3850 mm with two different concrete quality of K-300 and K-400 have been tested. Three (3) of those specimens are solid reinforced concrete beams with concrete quality of K-400 is used as benchmark beam. Four point loading test was chosen to investigate flexural behavior of the beams. The test results were analyzed based on graphical relationship between load – displacement, moment - rotation at beam midspan, and the crack pattern of each specimen.

The results showed that flexural strength of HCB K-400 is 0.98 times of solid beam with similar concrete quality. HCB K-300 has flexural strength of 0.965 compared to HCB K-400. The research gives an overview of the making process of cast in site HCB that can be applied in construction site."

"This book presents a wide-ranging review of the latest research and development directions in thermal systems optimization using population-based metaheuristic methods. It helps readers to identify the best methods for their own systems, providing details of mathematical models and algorithms suitable for implementation.To reduce mathematical complexity, the authors focus on optimization of individual components rather than taking on systems as a whole. They employ numerous case studies: heat exchangers; cooling towers; power generators; refrigeration systems; and others. The importance of these subsystems to real-world situations from internal combustion to air-conditioning is made clear.The thermal systems under discussion are analysed using various metaheuristic techniques, with comparative results for different systems. The inclusion of detailed MATLAB® codes in the text will assist readers-researchers, practitioners or students-to assess these techniques for different real-world systems."

"Systematic consideration of environmental aspects within the early stages of product development (PD) can be considered highly significant in order for the overall environmental performance of the product to be improved. Many methods and tools have been developed aiming to enable this consideration and provide the properties that need to be considered and improved. This article provides an overview of some well-known and more applicable tools and methods that have been developed and are available today. The identified tools are generally classified in two groups: Guidelines and Analytical tools. The limitations and barriers of current tools are assessed and categorized and two areas for work are proposed in order to address current limitations in the existing literature. One of the areas is followed and a scoring model is proposed as a new tool for sustainable PD."

"Biotechnology is an expansive field incorporating expertise in both the life science and engineering disciplines. In biotechnology, the scientist is concerned with developing the most favourable biocatalysts, while the engineer is directed towards process performance, defining conditions and strategies that will maximize the production potential of the biocatalyst. Increasingly, the synergistic effect of the contributions of engineering and life sciences is recognised as key to the translation of new bioproducts from the laboratory bench to commercial bioprocess. Fundamental to the successful realization of the bioprocess is a need for process engineers and life scientists competent in evaluating biological systems from a cross-disciplinary viewpoint. Bioprocess engineering aims to generate core competencies through an understanding of the complementary biotechnology disciplines and their interdependence, and an appreciation of the challenges associated with the application of engineering principles in a life science context. Initial chapters focus on the microbiology, biochemistry and molecular biology that underpin biocatalyst potential for product accumulation. The following chapters develop kinetic and mass transfer principles that quantify optimum process performance and scale up. The text is wide in scope, relating to bioprocesses using bacterial, fungal and enzymic biocatalysts, batch, fed-batch and continuous strategies and free and immobilised configurations."