Hasil Pencarian  ::  Simpan CSV :: Kembali

"The effect of rice husk ash produced at different grinding times on the engineering properties of concrete was studied. Eight rice husk ashes representing different grinding times were used in this investigation. Rice husk ash (RHA) was used to partially replace Port land cement Type I at 15% by weight of cementitious material. The compressive strength of concrete was designed to achieve grade 40 N/mm2 at 28 days. A superplasticizer was added to all mixes to provideworkability in the range of 110-120 mm. However, the water to cement ratio (w/c) of the concrete was maintained at 0.49. Based on the results, the morphology of the rice husk ashes was changed by grinding. Optimum grinding time appeared to be approximately 90 minutes, during which time the compressive strength increased significantly. Generally, incorporation of RHA at various grinding times can dramatically decrease or increase the engineering properties of concrete. "

"Engineering design calculations for tank bottom sections, including direct current requirements and voltage calculations, followed by additional structures, such as electrical grounding systems, have already been successfully implemented and controlled in field conditions. Furthermore, the effect of soil resistivity in layers, oxygen content and the pH value of the soil against the disproportionate IR-Drop voltage, including its effect on potential distribution, have been already successfully observed. Other influences, such as the depth and location of the anode groundbed determination along with the establishment of impressed current cathodic protection related to the main tools and equipment, such as external corrosion control methods, have been defined as the most effective ways in order to control potential distribution against the additional structures. Persuant to the verification results from the site located at Marangkayu, East Borneo, it has been determined that high soil resistivity could cause error readings in accordance with the accumulation results of the true readings and the IR-Drop voltage, since under real conditions, the tank structure would have received less current flow from an anode compared to a lower result. Naturally, a low pH value from the soil would decrease soil resistivity and enhance potential distribution from the anodes to the tank structures. The results show that the cathodic protection required 10 additional anodes, (each one is of a tubular mixed metal oxide) with a DC supply at minimum amperage of 154 Amps and a minimum voltage supply of 32 Volts. During the research, it was identified that high soil resistivity above 3000 ohm-cm would cause error readings. Naturally, acidic soil is in the region of pH 5-7 value, which would decrease soil resistivity and enhance the potential distribution from the anode to the tank structure."

"Analisis yang akan dilakukan terhadap penambat rel jenis KA Clip adalah pemodelan elemen hingga pada model struktur KA Clip. Pemodelan dilakukan dalam elemen solid dan elemen pelat untuk beban statis akibat adanya penjepitan (Clamping Force) pada saat terpasang. Dalam analisis statis pemodelan elemen hingga struktur KA Clip dengan memanfaatkan program aplikasi elemen hingga dan pengujian statis maka analisis yang dilakukan adalah membandingkan seberapa jauh keabsahan dan idealnya model elemen hingga yang dibuat bila dibandingkan dengan struktur yang sebenarnya.Kaji perbandingan tersebut meliputi gaya cekam (Clamping Force), defleksi (Displacement) serta tegangan yang terjadi (Stress Von Mises), dan dihubungkan dengan diagram Goodman untuk menentukan umur pakai penambat rel tersebut.Hasil dari penelitian, diperoleh adanya bentuk dan perubahan contour warna pada kedua jenis elemen tersebut akibat adanya gaya jepit sebesar 750 kgf sampai dengan 1300 kgf. Berdasarkan nilai Stress Von Mises pada pembebanan 1000 kgf yang dipilih, elemen solid menunjukkan nilai yang masih dibawah nilai luluh bahan yaitu 1175 N/mm2, dan jika dilihat terhadap defleksi yang terjadi elemen solid menunjukkan nilai defleksi yang lebih kecil (sesuai keinginan). Hasil ini juga memberikan kesamaan dengan bentuk modifikasi KA Clip pada ketebalan 5 mm maupun 7 mm. Terhadap tegangan yang terjadi ini, bila dikaitkan dengan diagram Goodman menunjukkan umur yang terhingga dalam penggunaannya.

---

Analysis will be done to Spring Clip type KA Clip was modeling finite element to model structural KA Clip. Modelings are done inside Solid element and Plate element for static force due to Clamping Force when it installed. In static analysis of modeling finite element structure of KA Clip using application Program for Finite Element and statistical test, the analysis try to compare how far is the legality and the ideal of finite element model is being made compare to real structure.The comparison include Clamping Force, Displacement, and the Stress Von Mises, and it's connected with Goodman diagram to know how long the usage of Spring Clip.The result of this research found out that there are form and changes color contour in both elements due to Clamping Force 750 kgf- 1300 kgf. Based on the value Stress Von Mises in 1000 kgf that being chosen, solid element showed the value under yield point material value 1175 N/mm2, and if seen to deflection have done for solid element showed little displacement point. The simulation shows the same result for the modified form with the thickness 5 mm or 7 mm. For this stress, if to connect with Goodmand diagram showed age is finite in used."

"Penelitian mengenai pendeteksian terhadap ruang terbatas proses pemesinan awal 5 Axis, merupakan salah satu bagian dalam pengembangan sistem CAM yang berbasis model faset 3D. Ruang terbatas dibedakan menjadi 2 bagian yaitu ruang terbatas terbuka dan ruang terbatas tertutup. Perbedaan ruang terbatas terbuka dan ruang terbatas tertutup yaitu perlunya orientasi pahat untuk proses pengerjaan ruang terbatas tertutup.Dalam penelitian ini pendeteksian ruang terbatas dilakukan dengan mendeteksi kebertumpukan segitiga dalam bidang x dan y dan perbedaaan arah vektor normal terhadap sumbu radius pahat. untuk mendapatkan hasil deteksi pahat pada ruang terbatas, penulis mengembangkan algoritma-algoritma dalam mengolah data yang berupa STL file. Metode yang telah dikembangkan ini kemudian di uji terhadap beberapa model produk dan mampu memberikan informasi mengenai adanya ruang terbatas dan areanya.

---

The research concerning of bounded volume detection method for roughing process in multi-axis milling is one of a section to develop CAM system wich based on faceted model 3D. The bounded volume have 2 part wich very important, that is close boundary volume and open Boundary volume. The differences of open boundary volume and close boundary volume is tool oriented needed in machining process for close boundry volume.

In this research. Boundary volume will be get with detection of stacking of triangle and the differences of normal vector with normal angle of radius tool. To get bounded volume detection result, The writer develop algorithms to processing of STL file. The method which have been developed will be test to some models product and can give information regarding the existence of bounded volume area."

"Penelitian mengenai pendeteksian terhadap ruang terbatas proses pemesinan awal 5 Axis, merupakan salah satu bagian dalam pengembangan sistem CAM yang berbasis model faset 3D. Ruang terbatas dibedakan menjadi 2 bagian yaitu ruang terbatas terbuka dan ruang terbatas tertutup. Perbedaan ruang terbatas terbuka dan ruang terbatas tertutup yaitu perlunya orientasi pahat untuk proses pengerjaan ruang terbatas tertutup.Dalam penelitian ini pendeteksian ruang terbatas dilakukan dengan mendeteksi kebertumpukan segitiga dalam bidang x dan y dan perbedaaan arah vektor normal terhadap sumbu radius pahat. untuk mendapatkan hasil deteksi pahat pada ruang terbatas, penulis mengembangkan algoritma-algoritma dalam mengolah data yang berupa STL file. Metode yang telah dikembangkan ini kemudian di uji terhadap beberapa model produk dan mampu memberikan informasi mengenai adanya ruang terbatas dan areanya.

---

The research concerning of bounded volume detection method for roughing process in multi-axis milling is one of a section to develop CAM system wich based on faceted model 3D. The bounded volume have 2 part wich very important, that is close boundary volume and open Boundary volume. The differences of open boundary volume and close boundary volume is tool oriented needed in machining process for close boundry volume.

In this research. Boundary volume will be get with detection of stacking of triangle and the differences of normal vector with normal angle of radius tool. To get bounded volume detection result, The writer develop algorithms to processing of STL file. The method which have been developed will be test to some models product and can give information regarding the existence of bounded volume area."