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Abstrak :
Sifat mampu bentuk baja lembaran merupakan salah satu kemampuan yang diperlukan dalam proses manufaktur. Dengan adanya sifat mampu bentuk yang baik, ditunjang dengan faktor – faktor yang sesuai, maka industri lembaran baja dapat semakin berkembang. Salah satu faktor yang sangat penting dalam proses manufaktur adalah tingkat laju aliran regangan dari material. Dalam sebuah studi, diketahui bahwa untuk memperoleh informasi mengenai laju aliran regangan dari material adalah dengan melakukan uji regangan dengan tiga kecepatan pukulan yang berbeda dalam uji stretching dengan menggunakan ujung punch berbentuk hemispherical. Selain itu, forming limit curve (FLC) digunakan sebagai acuan dalam pembentukan lembaran baja, sehingga akan dilakukan studi korelasi antara kecepatan pukulan terhadap FLC0. Pengujian kali ini akan berfokus pada evaluasi pengaruh kecepatan punch terhadap pembentukan FLC0 dengan material yang digunakan 2 lembar baja karbon rendah tipe SPCD 1 mm dan SPCE 0.35 mm. Material uji sebelumnya dilakukan penandaan dengan pola lingkaran ukuran diameter 2 mm pada permukaannya. Pengujian metode Nakazima dilakukan menggunakan alat universal sheet metal testing machine kapasitas 12 tonF, dengan hasil uji berupa grafik kurva batas pembentukan (FLC). ......Formability sheet metal is one of capabilities that needed in the manufacturing process. With a good formabilty of sheet metal, supported by appropiate factors, industry of sheet metal forming can be develop further more. One of the most important factors in the manufacturing process, especially formability sheet metal, is the strain flow rate of material. It is known that to obtain information about strain rate of the material is to perform formability test known as stretching test that in this study with a three different punch speeds using a hemispherical punch. In addition, the forming limit curve (FLC0) is used as a reference in the formation of steel sheets, because of that, it will be perform study that carried out correlation between speed punch and FLC0. This study will be focus on evaluating the effect of punch speed on the formation of FLC0 used low carbon steel sheets of  1 mm SPCD type and 0.35 mm SPCE type. Sample was marked with a 2 mm cirlce pattern on its surface. The Nakazima test method was carried out using a universal sheet metal testing machine with a capacity of 12 tonF with a graph of FLC0 as a result.

Abstrak :
Kecepatan rotasi mesin uap Skala kecil dapat dikendalikan dengan pengendali proporsionai-plus-integral (PI) atau pengendali logika fuzzi, FLC (Fuzzy Logic Controller) berbasis komputer. Untuk mengendalikan kecepatan mesin dengan pengendali PI perlu diturunkan fungsi alih mesin dan dihitung parameter-parameter pengendali yaitu Kp dan K1. Sedang untuk pengendalian dengan FLC tidak perlu melakukan penurunan fungsi alih, tetapi perlu proses fuzzifikasi, membuat basis aturan, proses penalaran, dan defuzzifikasi. Kestabilan sistem dengan pengendali PI dan parameter-parameter pengendali dianalisis dengan prosedur Tempat Kedudukan Akar. Respons sistem kedua pengendali dan dipantau pada monitor komputer dengan program yang ditulis dalam bahasa pemrograman Pascal 7.0/DOS, Delphi 5 dan Fuzzytech 5.12. Respons sistem pengendalian dengan pengendali PI dan FLC dapat dibandingkan untuk mengetahui kelebihan dan kekurangannya. ......The speed of a small scale steam engine can be controlled by a computer based proportional-plus-integral (PI) controller, or fuzzy logic controller (FLC). To regulate the engine speed by PI controller, the transfer function of the engine and the gain parameters of the controller, the proportional gain, Kp and the integral gain, KI must be derived. On the other hand the speed regulation by PLC, all of the factors mentioned above neet not be derived, but a fuzzification process, a construction of the rule base, a fuzzy reasoning dan a defuzzification process must be implemented. The stability of the PI controlled system and the parameters of the controller are analyzed by the root locus procedure. System responses of the two controlled systems are processed and monitored on the computer screen by a program written in Pascal 7.O,DOS, Delphi 5 and Fuzzytech 5.12. The system responses are compared to show their strengths and weaknesses.

Abstrak :
The major problem in serviceability degradation of steel truss bridge is interaction of moving vehicle load with the bridge 's upper structure. One of the improvement efforts is to strengthen the bridge system by using eternal pretension tendon. Pretension tendons with polygonal, kingpost and horizontal configuration are designed as an active control equipped with the actuator. Based on adaptive control technique, fuzzy logic algorithm was used to activate the tendon control in the bridge as a Fuzzy Logic Control feedback ( FLC feedback) system, where the change of control force can be set to be proportionalbr adaptable to the displacement. From the simulation with various cable configurations, with various velocities of continuous and discontinuous vehicle models, and various types of tendons, it shows that the Kingpost tendon configuration has a better performance to reduce the displacement of the bridge 's upper structure and to minimize tensile stresses at bottom chord element.