Hasil Pencarian  ::  Simpan CSV :: Kembali

"Mesin pembakaran dalam yang irit bahan bakar dipengaruhi oleh desain dan material yang digunakan. Semakin ringan bobot dari mesin maka akan semakin ringan pula bobot dari kendaraan sehingga kendaraan tersebut menjadi irit bahan bakar. Desain mesin yang sederhana dan ringan tanpa melupakan fungsinya merupakan landasan terciptanya mesin irit bahan bakar. Cylinder head dan camshaft assembly merupakan salah satu komponen penting yang mempengaruhi kinerja mesin. Berdasarkan hasil perhitungan analitik pada penelitian ini diperoleh dimensi dari tinggi cylinder head (L) sebesar 24 mm, diameter camshaft (d) adalah 6 mm, tinggi(h) dan lebar (b) rocker arm adalah 8,44 mm dan 4,22 mm, dan nilai konstanta pegas (K) berdasarkan rekayasa balik adalah 10300,5 N/m. Selain itu pada penelitian ini dibahas mengenai kekuatan cylinder head, camshaft, rocker arm, dan pegas dengan membandingkan nilai Von Mises stress yang didapat melalui perhitungan analitik dengan perhitungan numerik dengan bantuan software ANSYS 14. Nilai Von Mises stress menggunakan perhitungan analitik pada cylinder head adalah 49,029 MPa, pada camshaft titik C dan titk D adalah 206,63 dan 297,16 MPa, pada rocker arm adalah 21 MPa, dan untuk pegas adalah 451,8 MPa. Sedangkan menggunakan perhitungan numerik pada cylinder head adalah 48,519 MPa, pada camshaft titik C dan D adalah 65,288 dan 406,58 MPa, pada rocker arm adalah 66,078 MPa, dan pada pegas adalah 844,49 MPa. Analisis fatigue digunakan untuk mendapatkan lifetime dari cylinder head adalah 2 tahun, camshaft adalah 4 tahun, rocker arm adalah 1,7 tahun, dan pegas 1 tahun.

---

Combustion engine in which fuel economy is affected by the design and materials used. The lighter weight of the engine will also be light weight of the vehicle so that the vehicle to be fuel efficient. A simple design and lightweight machines without forgetting its function is the main idea to create fuel efficient engine. Cylinder head and camshaft assembly is one of the important components that affect engine performance. Based on the results of analytical calculations in this research were obtained from a height of cylinder head (L) is 24 mm, diameter of the camshaft (d) is 6 mm, height (h) and width (b) of rocker arm is 8.44 mm and 4.22 mm , and the value of the spring constant (K) based on reverse engineering is 10300.5 N / m. In addition, this study discussed the strength of the cylinder head, camshaft, rocker arm, and spring by comparing the value of Von Mises stress obtained through analytical calculations with numerical calculations with the help of ANSYS software 14. Von Mises stress values using analytic calculations on the cylinder head is 34.29 MPa, the camshaft on points C and D are 206.63 and 297.16 MPa, the rocker arm is 21 MPa, and for spring is 260.85 MPa. While using numerical calculations on the cylinder head is 48.519 MPa, camshaft on point C and D are 65.288 and 406.58 MPa, rocker arm is 66.078 MPa, and the spring is 844.49 MPa. Fatigue analysis is also used in simulation using ANSYS 14 to obtain the lifetime of the cylinder head is 2 years before failure, camshaf is 4 years, rocker arm is 1.7 years, and spring is 1 year."

"Technetium 99m, yang dihasilkan melalui molybdenum-99, merupakan radioisotop terbanyak digunakan di dunia kedokteran nuklir. Untuk memproduksi molybdenum-99, sekarang ini sedang dikembangkan reaktor nuklir jenis aqueous homogeneous reactor (AHR). Meskipun penelitian terkait AHR telah banyak dilakukan, belum begitu banyak referensi yang membahas tentang aspek materialnya, padahal aspek material merupakan salah satu hal yang penting untuk diperhatikan dalam mendisain AHR. Dalam hal ini, salah satu hal yang perlu untuk diteliti adalah berhubungan dengan integritas struktural bejana AHR yang diakibatkan oleh stress akibat adanya tekanan serta suhu operasi reaktor. Desain dari bejana harus mampu menahan kondisi pengoperasian normal, kondisi kecelakaan atau abnormal yang mungkin, serta mempertimbangkan adanya cacat retak yang mungkin ada pada bejana. Penelitian ini dilakukan melalui simulasi komputer metode finite elemen (FEM) dengan bantuan software ANSYS sedangkan verifikasinya dilakukan secara eksperimental. Akan tetapi, karena kompleksnya permasalahan dalam sebuah reaktor, maka verifikasi hanya dilakukan dengan cara membandingkan hasil uji tarik pada kondisi AHR dengan simulasi uji tarik dengan ANSYS. Hasil uji tarik secara eksperimen dan uji tarik secara simulasi ANSYS menunjukan korelasi yang sangat baik sehingga diasumsikan bahwa simulasi yang dilakukan dapat mewakili kejadian yang sebenarnya. Hasil simulasi pada AHR menunjukan bahwa tekanan dan suhu pada bejana berpengaruh pada stress material bejana. Semakin tinggi tekanan dan suhu pada bejana maka akan semakin tinggi juga stress yang diterima oleh material bejana. Ukuran cacat retak yang disimulasikan pada bejana juga memberikan pengaruh pada nilai stress intensity factor (SIF) yang dihasilkan dimana semakin besar ukuran cacat retak, akan menghasilkan nilai SIF yang juga semakin tinggi. Penggunaan material reflektor juga memberikan pengaruh yang signifikan terhadap stress yang diterima oleh bejana reaktor. Hal ini disebabkan adanya tambahan stress yang berasal dari thermal stress antara material bejana dan juga material reflektor. Dari seluruh simulasi yang dilakukan, nilai equivalent (von-Mises) stress yang dihasilkan masih dibawah nilai yield strength dan fracture toughness (KIC) bejana AHR sehingga integritas bejana masih terjaga dan retak yang ada tidak mengalami propagasi menjadi suatu kegagalan.

---

Technetium-99m, which is generated through a source of decaying molybdenum-99, is the the most commonly used medical radioisotope. To produce molybdenum-99, nuclear reactor types of homogeneous aqueous reactor (AHR) are being developed by many investigators. Although AHRs-related research have been done, yet many references that discuss the aspects of the material are rarely available. At the same time, material is one of important aspects to consider in designing AHR. In this case, one thing that needs to be investigated in relation to the structural integrity of AHR vessels is the stress caused by the pressure and temperature of the reactor operation.

The design of vessels needs to consider many aspects such as normal operating conditions, possibility of accident or abnormal conditions, as well as consideration of the existence of defects that may exist in the vessel. This research was peformed through a computer simulation by using finite element method (FEM) available in ANSYS. The validity of the simulation was then verified experimentally. However, due to the complication of the reactor, verification was just conducted by comparing the experimental results of tensile test at AHR contiditon with the tensile test simulated by using ANSYS.

The results of the experimental tensile test and the tensile test simulated by using ANSYS showed an excellent correlation. In this case, the results of the simulation was assumed to represent the actual event. The simulation results on AHR show that pressure and temperature in the vessel affect the stress of the vessel material. The higher the pressure and temperature in the vessel, the higher the stress of the vessel material. The size of the simulated crack defects in the vessels also affects the value of stress intensity factor (SIF); the greater the crack the higher the SIF value.

The use of reflector material also has a significant influence on the stress experienced by the vessel reactor. This is due to the additional stress from thermal stress between the vessel and reflector materials. However the equivalent (von-Mises) stressess obtained from all of the simulation are still below the yield strength and fracture toughness (KIC) of the AHR vessel so that the integrity of the vessel is maintained and that any existing cracks would not propagate to becomea a failure."

"ABSTRAK Latar Belakang Pada penatalaksanaan fraktur maksilofasial secara internal fiksasi diperlukan pemasangan alat miniplate dan screw sampai terjadi penyembuhan tulang Magnesium memiliki potensi sebagai miniplate dan screw pada tulang rahang dengan syarat bersifat biokompatibel dan biodegradasi sehingga tidak diperlukan operasi kembali untuk pengambilan miniplate dan screw Proses equal channel angular pressing ECAP merupakan salah satu metode untuk mengontrol laju korosi logam magnesium dan meningkatkan sifat mekanisnya Untuk pembuatan desain miniplate dan screw dari magnesium ECAP dengan merujuk dari desain safety factor bahan titanium yang biasanya telah digunakan perlu disesuaikan dengan material properti magnesium agar dapat mencegah kerusakan Tujuan menganalisa perbandingan desain miniplate dan screw logam magnesium ECAP terhadap titanium Metode Untuk penelitian ini kami menggunakan metode finite elemen yaitu formulasi perpindahan untuk menghitung perpindahan komponen strain dan tekanan di bawah beban internal dan eksternal Kemudian desain miniplate dan screw dari magnesium ECAP dilakukan analisa simulasi pembebanan yang dianalisa menggunakan teori Von Misses Hasil Hasil desain miniplate dan screw magnesium ECAP yang diharapkan dapat digunakan pada penatalaksanaan fraktur maksilofasial telah dilakukan simulasi pembebanan dengan dilakukan analisa desain menggunakan teori Von Misses kemudian desain direkayasa untuk mengurangi stress yang diterima desain rekayasa magnesium ECAP dibuat menjadi dua tipe yaitu tipe 1 dengan menambah jumlah screw menjadi 8 screw dengan berat total miniplate dan screw sebesar 118 212 mg dan tipe ke 2 dengan merubah diameter head screw menjadi 2x lebih besar dari bentuk semula sehingga berat totalnya sebesar 169 414 mg Kesimpulan Desain alternatif miniplate dan screw magnesium ECAP tipe 1 dapat lebih efektif untuk digunakan pada penatalaksanaan fraktur maksilofasial ABSTRACT Background In the internal fixation management of maxillofacial fractures the placement of miniplate and screw is necessary until bone repair takes place Magnesium has the potential as a miniplate and screw for the jaws with it rsquo s biocompatibility and biodegradability so that a follow up surgery to remove the miniplate and screw is not necessary The equal channel angular pressing ECAP process is a method to control the corrosion rate of magnesium and increase the mechanical properties In the making of miniplate and screw design from ECAP magnesium referring the safety factor of the titanium design that is already being used adjustments must be made with the characteristics of magnesium so damage can be avoided Objectives to analyze the comparison between magnesium ECAP miniplate and screw design against titanium Methods For this research we used the finite element method which is displacement formulation to calculate component movement strain and pressure under the internal and external load Afterwards the magnesium ECAP miniplate and screw design undergoes a loading simulation which is analyzed with the Von Misses theory Result Design of miniplate and screw magnesium ECAP which expected to be used in the management of maxillofacial fractures has been tested with the stress simulation using Von Misses theory then the design engineered to reduce stress received Engineering design of magnesium ECAP divided into two types type 1 by increasing the number of screw into 8 screws with a total weight miniplate and screws with a total weight miniplate and screw amounted to 118 212 mg and type 2 by changing the diameter of the head screw becomes large than its original shape so that the total weight of 169 414 mg Conclusion Design alternative of miniplate and screw magnesium ECAP type 1could be more effective to be used in the management of maxillofacial fracture ;Background In the internal fixation management of maxillofacial fractures the placement of miniplate and screw is necessary until bone repair takes place Magnesium has the potential as a miniplate and screw for the jaws with it rsquo s biocompatibility and biodegradability so that a follow up surgery to remove the miniplate and screw is not necessary The equal channel angular pressing ECAP process is a method to control the corrosion rate of magnesium and increase the mechanical properties In the making of miniplate and screw design from ECAP magnesium referring the safety factor of the titanium design that is already being used adjustments must be made with the characteristics of magnesium so damage can be avoided Objectives to analyze the comparison between magnesium ECAP miniplate and screw design against titanium Methods For this research we used the finite element method which is displacement formulation to calculate component movement strain and pressure under the internal and external load Afterwards the magnesium ECAP miniplate and screw design undergoes a loading simulation which is analyzed with the Von Misses theory Result Design of miniplate and screw magnesium ECAP which expected to be used in the management of maxillofacial fractures has been tested with the stress simulation using Von Misses theory then the design engineered to reduce stress received Engineering design of magnesium ECAP divided into two types type 1 by increasing the number of screw into 8 screws with a total weight miniplate and screws with a total weight miniplate and screw amounted to 118 212 mg and type 2 by changing the diameter of the head screw becomes large than its original shape so that the total weight of 169 414 mg Conclusion Design alternative of miniplate and screw magnesium ECAP type 1could be more effective to be used in the management of maxillofacial fracture ;Background In the internal fixation management of maxillofacial fractures the placement of miniplate and screw is necessary until bone repair takes place Magnesium has the potential as a miniplate and screw for the jaws with it rsquo s biocompatibility and biodegradability so that a follow up surgery to remove the miniplate and screw is not necessary The equal channel angular pressing ECAP process is a method to control the corrosion rate of magnesium and increase the mechanical properties In the making of miniplate and screw design from ECAP magnesium referring the safety factor of the titanium design that is already being used adjustments must be made with the characteristics of magnesium so damage can be avoided Objectives to analyze the comparison between magnesium ECAP miniplate and screw design against titanium Methods For this research we used the finite element method which is displacement formulation to calculate component movement strain and pressure under the internal and external load Afterwards the magnesium ECAP miniplate and screw design undergoes a loading simulation which is analyzed with the Von Misses theory Result Design of miniplate and screw magnesium ECAP which expected to be used in the management of maxillofacial fractures has been tested with the stress simulation using Von Misses theory then the design engineered to reduce stress received Engineering design of magnesium ECAP divided into two types type 1 by increasing the number of screw into 8 screws with a total weight miniplate and screws with a total weight miniplate and screw amounted to 118 212 mg and type 2 by changing the diameter of the head screw becomes large than its original shape so that the total weight of 169 414 mg Conclusion Design alternative of miniplate and screw magnesium ECAP type 1could be more effective to be used in the management of maxillofacial fracture "

"AbstrakProses perancangan dan analisis kontruksi tower dimulai dengan mengidentifikasi semua kebutuhan, kemudian memberikan kriteria disain yang diinginkan. kriteria desain yang dimunculkan transportasi dan pemasangan. arm- wiss adalah augmented reality mobile weapon impact scoring system merupakan sebuah alusista baru tni au yang dirancang agar mampu memantau, menilai, menganalisis dan mengevaluasi latihan untuk mendukung pencapaian safety yang lebih tinggi, mengembangkan taktik dan strategi pertempuran dan meningkatkan kualitas pemeliharaan alutsista seperti pesawat dan pendukungnya pada erbagai aspek secara tepat."

"Perancangan sistem konveyor pada penelitian ini dimaksudkan untuk memenuhi beberapa tujuan yang berkaitan dengan peningkatan kualitas produksi perusahaan serta menerapkan konsep keselamatan kerja yang sesuai dengan standar yang berlaku terhadap sumber daya manusia yang ada. Beberapa komponen sistem konveyor ini dirancang menggunakan perangkat lunak desain Autodesk Inventor dengan simulasi menggunakan Autodesk Inventor untuk analisis tegangan dan Catia untuk analisis ergonomik. Perhitungan yang disajikan untuk mendukung keabsahan desain difokuskan kepada peninjauan traksi maksimum yang terjadi pada beberapa titik kontak, yaitu antara caster dengan rel sebesar 136.487,78 N, pengait dengan plat penyangga bawah sebesar 15.084,54 N, dan sabuk terhadap plat penyangga atas sebesar 14.873,08 N. Simulasi dilakukan untuk mengetahui pengaruhnya secara langsung maupun tidak langsung terhadap komponen terkait dan memberikan penilaian berdasarkan properti mekanik material yang digunakan. Hasil simulasi tegangan menggunakan analisis Von Mises akan dinilai berdasarkan faktor keselamatan sementara hasil analisis ergonomik akan disajikan dalam bentuk RULA Rapid Upper Limb Assessment dalam bentuk skor resiko terjadinya MSD Musculoskeletal Disorders. Hasil simulasi menunjukkan bahwa traksi berpengaruh terhadap properti korosif material serta kekuatan material dalam menahan beban. Sementara analisis RULA menunjukkan penggunaan sistem konveyor dapat mencegah terjadi tingkat severitas MSD yang tinggi pada pekerja.

---

The conveyor system design on this research is purposed to accomplish a few goals regarding companies production quality improvement and applying the concept of standarized work safety procedures among on field human resources. A few components of the conveyor system are designed using Autodesk Inventor while the simulations are represented using Autodesk Inventor for stress analysis, and Catia for ergonomic anaysis. The calculation that presented for supporting the design is focused on the maximum values of traction divided into 3 possible contact points, which are the contact between caster and railing which has the maximum tractions value of 136.48,78 N, the contact between hooks and the lower buffer plate which has the maximum tractions value of 15.084,54 N, and the contact between conveyors belt and the upper buffer plate which has the maximum traction rsquo s value of 14.873,08 N. The simulations are done to elaborate the direct and indirect possible effects to the components, also giving an analysis based on the mechanical properties of the used materials. The stress analysis will be represented using Von Mises criteria, giving the result of safety factor for each components. The ergonomic analysis will be represented using Rapid Upper Limb Assessment RULA, giving the result of musculoskeletal disorders MSD risk score. The results of the simulations indicated that traction influenced the corrosive and yield strength properties of some materials. While RULA analysis indicated that the using of conveyor system on the represented production line could prevents the high severity of MSD among operators."