This article presents a study of the contractors' preference for formwork system selection in Indonesian context. As decision makers, contractors are faced with challenges in choosing the formwork system for a particular project. While conventional timber formwork has been the most used formwork system in Indonesia, aluminium formwork is present although it has not been widely used. Thus, this research investigates the current practices of available formwork systems and its selection criteria in Indonesia. A decision-making framework (DMF) is developed by considering the appropriate assessment criteria for formwork system selection. This framework is then implemented through analytic hierarchy process technique. The result shows that contractors tend to choose aluminium formwork with a preference at 79% compared to conventional timber formwork with a preference at 21%. These findings can be used as considerations for contractors to start using aluminium formwork due to its excellence compared to conventional timber formwork. This study also proves that the proposed DMF can be applied and provides a sound decision related to formwork system selection.

Geopark is an area that has geological elements in which local people are invited to participate to protect and improve the function of the natural and cultural heritage in it. Kasepuhan Sinar Resmi is part of the cultural aspect that is inseparable from the Ciletuh Geopark which is still being preserved. The village always gets lots of visitors who want to know the original Sundanese culture, because the Kasepuhan Sinar Resmi Community still carries out the traditions of their ancestors. Nevertheless, the Kasepuhan Sinar Resmi Community does not close itself off from developments from the outside such as the use of technology in the village. The crafts of the local community have also started to be sold online and have good packaging. However, several problems have arisen, with the large number of tourists visiting the Kasepuhan Sinar Resmi making it often difficult for local traditional leaders to deal with them. In addition, selling products online is often used as a crime by some people who fake authentic products made by Kasepuhan Sinar Resmi. Another problem is that there is no real-time information management that is distributed globally to inform the activities being held and what facilities are available at Kasepuhan Sinar Resmi. This problem can be anticipated with a Web-Based Information System to be able to accommodate the needs of tourists as a Digital Information Source which can also be managed by the Kasepuhan Sinar Resmi community for Reservation services and online Product Marketing Media.

Beton Geopolimer merupakan beton yang menggunakan material anorganik produk sampingan hasil limbah padat industri yang disintesis melalui proses polimerisasi seperti fly ash, terak besi, terak nikel, dan material lainnya yang mengandung unsur Alumunium (Al) dan Silika (Si) yang tinggi.  Produksi 1 ton semen Portland menghasilkan emisi gas CO2 sebesar 1 ton ke atmosfer sehingga dapat membahayakan lingkungan seperti pemanasan global. Tujuan dari studi literatur ini adalah untuk menunjukan bagaimana karakteristik mekanik pada beton geopolimer dalam penggunaan 100% produk sampingan limbah industri (ferrous dan non-ferrous) sebagai pengganti semen Portland sepenuhnya pada beton konvensional, serta meninjau dampak lingkungan yang ditimbulkan akibat penggunaan limbah tersebut dengan menggunakan analisis TCLP. Toxicity Characteristic Leaching Procedure (TCLP) merupakan prosedur untuk mengetahui kadar logam berat pada produk sampingan limbah industri (ferrous dan non-ferrous) yang dapat larut dan dapat mencemari lingkungan. Studi pustaka yang membahas material anorganik mengenai beton geopolimer secara holistik masih sedikit.  Beberapa faktor yang dapat memengaruhi karakteristik mekanik beton geopolimer antara lain proporsi campuran, penggunaan admixture, pemilihan material anorganik, metode perawatan dan durasi perawatan, dan rasio larutan alkali sebagai aktivator. Proporsi campuran yang tepat dapat menghasilkan workability yang baik, kuat tekan, dan kuat tarik belah yang tinggi. Metode dan durasi perawatan dengan pemanasan (oven curing) mampu menghasilkan kekuatan mekanik yang lebih besar dibanding dengan metode perawatan suhu ruangan. Studi literatur ini diharapkan dapat memberikan pedoman dalam pengembangan beton geopolimer kedepannya bagi para peneliti dan industri.

The habit of wasting water is widespread. One of the solutions is to “force” the consumer to conserve water by restricting the flow using a restrictor with the orifice principle. The aim of this study was to determine the performance of a restrictor in a pipeline model by defining the discharge coefficient obtained experimentally from the output discharge with or without the restrictor in static pressure water, and to examine the variation based on the tap opening. The restrictor had an opening at the center of the cylinder with a 2.5 mm diameter and it was installed in a water tap of 0.5 inches diameter based on the market. The effectiveness of the tool in reducing the water was determined by the discharge coefficient. Based on the results, it was found that the restrictor was capable of reducing the water discharge output by 60%-70% for discharge inputs ranging from 0.15 to 0.25 l/s. Moreover, the reduction for discharge inputs below 0.15 l/s resulted in an efficiency ranging from 30%-40%. The discharge output using the restrictor was approximately 0.06 to 0.07 l/s. The contraction coefficient and expansion coefficient were 1.720 (experimental) and 1.484 (theoretical). Keywords: water wasting reduction, water restrictor, orifice principle, experimental approach

The usage of cement in concrete caused the release of CO2 emission which can cause global warming. Moreover, cement as main ingredient can result in depletion or even loss of limestone which serves as a water supplier for farmers. Geopolymer concrete does not use cement but industrial byproducts containing aluminate (Al) and silicate (Si) such as slag, fly ash, and metakaolin. Moreover, these materials are from industrial solid waste (slag) so that it becomes an added value for construction. This paper discusses the durability of geopolymer concrete with material derived from the ferrous and non-ferrous melting processes because of the lack of study in durability. In construction, the concrete durability is the main thing that must be considered. Durability analysis aims to make the concrete last a long time, especially in aggressive environments. It refers to high concentrated CO2 level in an urban area or marine environment that has sodium chloride and sodium sulfate levels. Increasing of non-ferrous content can lower total pore volume in geopolymer binder while the macropores are formed. High-calcium ferrous content addition has pore-enhancing effect. The lower the porosity, the lower the permeability in the concrete. It lowers the water content and compounds such as chloride absorbed in concrete. Chloride and CO2 diffusion can cause carbonation in concrete leading to corrosion in steel reinforcement and shrinkage. This literature study aims to enhance knowledge in concrete durability so building construction can last as the planned period. Hence, the utilization of natural resources as construction material can be more efficient.