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"Fatigue of riveted lap joints between aluminium alloy sheets, typical of the pressurized aircraft fuselage, is the major topic of the present book. The richly illustrated and well-structured chapters treat subjects such as : structural design solutions and loading conditions for fuselage skin joints, relevance of laboratory test results for simple lap joint specimens to riveted joints in a real structure, effect of various production and design related variables on the riveted joint fatigue behaviour, analytical and experimental results on load transmission in mechanically fastened lap joints, theoretical and experimental analysis of secondary bending and its implications for riveted joint fatigue performance, nucleation and shape development of fatigue cracks in riveted longitudinal lap joints, overview of experimental investigations into the multi-site damage for full scale fuselage panels and riveted lap joint specimens, fatigue crack growth and fatigue life prediction methodology for riveted lap joints, residual strength predictions for riveted lap joints in a fuselage structure. The major issues of each chapter are recapitulated in the last section."

"Micro Friction Stir Spot Welding (m-FSSW) merupakan salah satu jenis solid state welding dengan menggunakan non-consumable tool ber-skala micro dengan ketebalan material <1 mm serta memanfaatkan gesekan dan axial force dalam prosesnya. Hasil dair pengelasan yaitu lap-joint pada satu titik. Pada penelitian ini dilakukan pengujian Geometri tool terhadap hasil pengelasan, sehingga didapatkan korelasi antara geometri tool, temperature, perubahan kecepatan putar, axial force, hasil uji tarik geser, dan uji micro dan macro. Pada eksperimen ini menggunakan 4 jenis tool yaitu, tool 1 (One stage shoulder 450), tool 2 (one stage shoulder 650), tool 3 (small taper), tool 4 (medium taper). Standar pengujian yang digunakan adalah ISO 14273 (Uji Tarik Geser) , ASTM E340 (Makrostruktur) , ASTM E407 (Mikrostruktur).  Pada eksperimen ini hasil uji tarik geser tertinggi yaitu 600,480 N dengan dwell time 4 detik dengan temperatur sekitar 321.5 ˚C terdapat pada tool 4 (Medium Taper). Pada hasil uji struktur makro dan mikro (crossection) terdapat daerah Stir Zone (SZ), Thermo-Mechanically Affected Zone (TMAZ), Heat Affected Zone (HAZ), Parent Metal (PM), Hook dan EXTD zone (pada tool 3 dan tool 4). Pada daerah SZ, terjadi rekristalisasi secara penuh (>220°C) sedangkan daerah TMAZ yang mengalami rekristalisasi sebagian akibat adanya panas dan mengalami perubahan sifat mekanik (120°C-250°C). dan untuk daerah HAZ atau daerah yang terpengaruhi panas namun tidak mengalami rekristalisasi (<220°C).  Pada pengujian Microstructure (crossection) menunjukkan Intermetallic Compound serta cacat yang ada dalam skala mikro dari sambungan pelat tipis AA1100 dan pelat tipis CuZn. Pada ekperimen ini terdapat pengaruh pada variasi dwell time terhadap geometry tool sehingga mempengaruhi distribusi temperatur, kecepatan putar, dan axial force yang mengakibatkan hasil kekuatan uji tarik geser meningkat dari dwell time 2s ke 4s, sedangkan mengalami penurunan pada dwell time 6s.

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Micro Friction Stir Spot Welding (m-FSSW) is a type of solid state welding using non-consumable micro-scale tools with a material thickness of <1 mm and utilizing friction and axial force in the process. The result of welding is a lap-joint at one point. In this research, tool geometry was tested on welding results, so that a correlation was obtained between tool geometry, temperature, changes in rotational speed, axial force, shear tensile test results, and micro and macro tests. In this experiment, 4 types of tools were used, namely, tool 1 (One stage shoulder 450), tool 2 (one stage shoulder 650), tool 3 (small taper), tool 4 (medium taper). The test standards used are ISO 14273 (Tensile Shear Test), ASTM E340 (Macrostructure), ASTM E407 (Microstructure). In this experiment, the highest shear tensile test result is 600,480 N with a dwell time of 4 seconds with a temperature of around 321.5 ˚C, was found on tool 4 (Medium Taper). In the macro and micro structure test results (crossection) there are Stir Zone (SZ), Thermo-Mechanically Affected Zone (TMAZ), Heat Affected Zone (HAZ), Parent Metal (PM), Hook and EXTD zones (on tool 3 and tool 4). In the SZ area, full recrystallization occurs (>220°C) while the TMAZ area experiences partial recrystallization due to heat and experiences changes in mechanical properties (120°C-250°C). and for HAZ areas or areas that are affected by heat but do not experience recrystallization (<220°C). The Microstructure (crossection) test shows the Intermetallic Compound and defects that exist on a micro scale from the joints of the AA1100 plate and the CuZn plate. In this experiment, there was an influence on variations in dwell time on the tool geometry, thus affecting the temperature distribution, rotational speed and axial force, which resulted in the shear tensile test strength results increasing from a dwell time of 2s to 4s, whereas it decreased at a dwell time of 6s."

"Kapal pelat datar merupakan salah satu bentuk kapal alternatif yang dapat memberikan kemudahan dalam proses perakitan. Tetapi, kapal pelat datar memiliki kekurangan pada sambungan lasan yang bertemu pada suatu titik dimana rawan terjadi kebocoran yang diakibatkan tegangan tinggi pada daerah hasil pengelasan. Oleh sebab itu, diperlukan penelitian mengenai cara penanggulangan terhadap masalah sambungan las yang bertemu pada satu titik. Salah satu ide yang berkembang saat ini yakni penambahan diamond plate dan circular plate dimana untuk mengetahui berapa besar pengaruh penambahan diamond plate dan circular plate maka dilakukan analisa dengan metode finite element analysis (FEA) dan eksperimental. Metode yang digunakan yaitu dengan menganalisa kekuatan, kekerasan, pengujian struktur mikro dan makro untuk mengetahui kekuatan dan perubahan struktur dari logam setelah pengelasan. Hasil dari pengujian kemudian dijadikan input pada perangkat lunak FEA untuk kemudian dianalisa dan diverifikasi dengan hasil simulasi pengujian tekuk (bending test) dengan benda uji yang sesuai dengan model simulasi. Dari hasil simulasi dan eksperimental didapatkan bentuk diamond plate yang berukuran 60x60 mm dengan ketebalan 6mm yang ideal untuk diterapkan pada kapal pelat datar.

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Flat-plated vessel is one of the alternative vessel shapes that can provide convenience in the assembly process. However, the flat-plated vessel has weakness in the welding joints that meet at a point which is prone to leak caused by maximum stress in the welded areas. Therefore, a study is required to seek the ways to solve the problem of welding joints which meet at one point. One of the recently developing ideas is the addition of diamond and circular plates. In order to find out the effect of the addition of diamond and circular plates, an analysis using finite element analysis (FEA) and experimental methods was conducted.

The methods are analyzing strength, hardness, micro and macro structure testing to determine the strength and changes of structure of the metal after welding. The results of the testing then became input to the FEA software for further analysis and verification with bending test simulation result of the specimen in accordance with the simulation model. The simulation and experiment resulted in the form of diamond plate 60x60 mm with a thickness of 6 mm which is ideal to be applied to flat-plated vessel."

"Hypermobility of joints 4th edition follows the same format as its successful predecessors. The aim of which was to provide an overview of hyperlaxity of joints and this edition follows that aim by describing the most recent research and new developments in biochemistry, as well as providing practical advice on clinical features and management.Hypermobility of joints 4th edition provides illustrative case histories, a review of hypermobility in the performing arts and sports and an outline of heritable hypermobility syndromes. This book is a valuable reference tool for a wide number of specialties, although it will particularly be of interest to rheumatologists, orthopedic surgeons and medical geneticists."

"Penelitian ini berfokus pada analisis pemilihan mesin dan propeler untuk sistem propulsi pesawat LSU-05 NG dengan melakukan kalkulasi kebutuhan daya dorong pesawat. Kebutuhan daya dorong dievaluasi pada dua kondisi pembebanan yaitu pembebanan berat (heavy loading) dengan memperhatikan kecepatan take-off minimum dan pembebanan ringan (light loading) dengan memperhatikan kecepatan terbang jelajah (cruise) maksimum. Selanjutnya dari lima rekomendasi mesin yang tersedia, dilakukan analisa efisiensi putaran propeler, gaya dorong yang dihasilkan, serta berat mesin yang memenuhi syarat DRO (Design Requirment and Objective) pesawat. Hasil penelitian ini memberikan rekomendasi penggunaan mesin yang memiliki daya minimal 16.5 hp dengan kandidat utama mesin DLE 170 dan propeler ukuran 32x10 sebagai sistem propulsi LSU-05 NG."