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"Pembangunan infrastruktur yang masif yang dilakukan pada akhir ini membuat banyak membutuhkan berbagai jenis baja sebagai penopang dari struktur infrastruktur tersebut. Salah satu jenis baja yang digunakan adalah high strength steel. Baja SM570 yang merupakan jenis high strength steel cocok digunakan sebagai material pada struktur jalan layang karena sifatnya yang kuat dan tangguh. Namun sifat mekanik baja ini jika dilakukan pengelasan akan menurun. Sehingga perlu dilakukan penelitian agar sifat mekanik dari baja SM570 tetap terjaga. Pada penelitian ini bertujuan untuk mengetahui pengaruh heat input terhadap mikrostruktur, distribusi panas dan tegangan sisa dengan pengalasan menggunakan metode Flux-Cored Arc Welding (FCAW) pada baja SM570-TMC. Pengelasan dilakukan menggunakan metode FCAW dengan gas pelindung CO₂ dan menggunakan empat variabel yang terdiri dari variabel kawat las dan arus. Kawat las yang digunakan adalah Primeweld E71 LT H4 (Ni=0,4%) dan Primeweld E81-K2 (Ni=1,5%). Arus yang digunakan adalah low heat input (0,9 kJ/mm) dan high heat input (1,4 kJ/mm). Terdapat pula pengujian yang dilakukan sebagai penunjang data dalam analisa yaitu pengujian kekerasan untuk mengetahui kekerasan di daerah hasil las, HAZ dan logam induk dengan metode vickers (ASTM E92-82), pengujian EPMA untuk mengukur unsur nikel pada daerah weld metal, pengamatan makro, pengamatan metalografi (ASTM E3-11) untuk melihat struktur mikro pada daerah logam induk, HAZ dan weld metal, pengamatan accicular ferrite dan inklusi pada hasil las menggunakan pengujian SEM/EDS. Selain pengujian diatas dilakukan pula simulasi distribusi panas dan tegangan sisa menggunakan ANSYS serta membandingkannya dengan pengujian menggunakan difraksi neutron.

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The massive development of infrastructure that being worked recently needed appropriate steel types as structure cantiveler. One of them is a high strength steel. SM570-TMC steel is a type of high strength steel that suitable for used as overpass road structure because of it's strength and toughness. However, the steel mechanical properties became lower after weld process. Research for this problem is important due to increasing the mechanical properties of SM570-TMC after welding process. This research is aim to investigate the effect of heat input of FCA welded steel SM570-TMC on microstructure, hardness and residual stress. FCAW was used for weld method with CO₂ as shield gas and used four variables consist of filler and current. Type of filler metal in this research is Primeweld E71 LT H4 (Ni = 0.4%) and Primeweld E81-K2 (Ni = 1.5%). Moreover, the weld parameter was used low heat input (0.9 kJ/mm) and the high heat input (1.4 J/mm). There are also testing to support data in the analysis, such as hardness testing, macro and micro structure observation. In addition, a simulation of heat distribution and residual stress is also carried out using ANSYS compared with residual stress using neutron diffraction."

"Cold-formed steel structural has a thinner dimensional typical steel structural than order standars steel structural which it has a thickness up to 8 mm and wider ratio dimensional....."

"Jenis baja tahan karat austenitik 316L banyak dipergunakan dalam dunia industri modern baik dalam gas dan perminyakan maupun dalam manufaktur. Hal ini dikarenakan baja tahan karat 316L yang memiliki sifat ketahanan korosi dan sifat mekanis yang baik. Selain itu, baja tahan karat 316L juga lebih banyak diminati mengingat harganya yang jauh lebih murah dibandingkan baja tahan karat duplek atau hiper duplek. Selain beberapa sifat di atas, baja tahan karat juga memiliki suatu sifat mampu las (weldability) yang baik, karena tidak dapat dipungkiri bahwa pengelasan merupakan sesuatu yang sangat penting dalam proses manufaktur maupun dalam perbaikan perbaikan peralatan yang rusak. Pada penelitian ini digunakan dua metode pengelasan yang berbeda yaitu GTAW (Gas Tungsten Arc Welding) dan SMAW (Shielded Metal Arc Welding), sehingga didapatkan suatu karakteristik antara pengelasan GTAW dan SMAW yang dapat digunakan untuk perbandingan kualitas hasil pengelasan. Pengujian yang dilakukan dalam penelitian ini antara lain, pengujian radiografi, metalografi, penentuan ferrite number (FN), dan pengujian kekerasan. Hasil dari penelitian ini menunjukkan bahwa lasan hasil GTAW memiliki kekerasan yang lebih tinggi dibandingkan dengan SMAW, dan kekerasan tertinggi terdapat pada daerah logam lasan pada setiap jenis pengelasan. Hasil penentuan FN menunjukkan bahwa logam lasan hasil GTAW memiliki jumlah fasa ferit yang lebih banyak dengan kadar rata-rata di atas 5% dibandingkan dengan logam lasan hasil SMAW dengan kadar rata-rata 3,2% - 3,3%.

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Austenitic stainless steel 316L is widely used in modern industries such as manufacture and oil and gas due to its both good corrosion resistance and good mechanical properties. Its also due to its price which is cheaper than duplex or hyperduplex stainless steels. Stainless steels also have good weldability since welding always takes an important role in manufacturing for services or maintenance aplications.

Two different methods of welding were used to weld austenitic stainless steel 316L in this research that are GTAW and SMAW for comparisson purpose. Experimental methods used are radiography, metalography, ferrite number determination and hardness test.

The result shows that weldment produced by GTAW has higher hardness than those SMAW one. Its acknowledge that for all methods of welding the hardest region is in weld metal. The weld metal ferrite number (FN) produced by GTAW has ferrite content with average above 5% of ferrite whereas the one produced by SMAW has 3,2% - 3,3% ferrite."

"Local wisdom was believed as a significant potency for some ethnics in Indonesia to sustain living inthe coastal areas. Bugis and Baja people were known as two ethnics among others who get used to livein the coastal areas, sailing across the ocean, and lived outside their traditional habitats. On the otherhand some coastal development policies, new introduced coastal activities, or natural hazards tend tochange the environmental conditions of their settlement. These could disturb the existence of theirsettlements in the coastal areas. Based on, private research on coastal settlement since 2002, this paperdescribed the role of tradition, adaptation, or transformation strategy of Bugis and Baja community tosurvive living in Jakarta, East Nusa Tenggara and West Nusa Tenggara islands and coastal settlements.Unsupported by information and awareness on new discoveries, improve interpretation on sustainableliving, and relevant government interventions, local wisdom could support them to survive but notsufficient to improve the coastal community resilience on coastal disaster and ensure the sustainability oftheir settlements in the coastal areas."

"Based on observations and in-depth interviews, Border Lives tells the story of how diverse groups of individuals came to establish roots in Tijuana, beginning shortly after the termination of the Bracero Program (1942-64) and ending in the present. It describes how these different groups of migrants and residents adapt to a dynamic borderlands economy and draw on the border as a resource to construct their livelihoods. The book details the consequences of border-enforcement and immigration restrictions over several decades, documenting the ways in which policies create precarious situations for those who cross the border and come in contact with them on a regular basis. The book shows how individuals have used the border as a resource in the past, and how current residents are forced to seek ways to access the opportunities that the border offers in the future. Yet for all of these border crossers-former, current, and future-the border itself figures significantly, not only in their livelihood strategy but also in their lifestyle, shaping their knowledge, action, and their relationships, controlling their time, and allowing them to convert US wages into a Mexican standard of living, without losing the social and cultural comforts of Tijuana-as-home."