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Optimation Front Upright Racing Car Using Finite Element Analysis
Get PDFUpright is part of the car's suspension system that plays an important role in creating and comforting the car. Supporting driving safety, upright components must be designed to be light but strong to withstand loading when the car is in conditions of acceleration, deceleration and cornering. Not only strong as a benchmark, but components must also be lightweight, so we need a method, namely a topology optimization method. Using finite element software makes the optimization process very easy and very fast with maximum accuracy. The process is by inputting the model from CAD software, defining materials, input constraints and vector styles, meshing process, and finally the solution process. From the simulation results, it will be known the value of the solution in the form of stress, deformation and safety factor of the upright component. From several topology optimization designs, they will be compared to find out which is the best design which will be used as a design recommendation. By referring the result, 43% mass reduction is the best optimum design, its safety factor is 4.956
Sifat Kemonotonan Barisan Trapezoid Sum dari Kelas Fungsi Nonkonveks dan Nonkonkaf
Get PDFThe objective of this research is to show the monotonicity properties of the trapezoid sum sequence in general of nonconvex or nonconcave real valued continuous functions on interval corresponding to partitions of obtained by dividing into equal length subintervals. The decreasing monotony of the trapezoid sum generically does not happen in class of nonconcave functions. The same thing happens when restricted to the monotone nonconcave functions, namely in class of nonconcave increasing or nonconcave decreasing functions. Furthermore, in class of nonconvex functions, the trapezoid sum sequence generically does not increasing, as well as in class of increasing nonconvex or decreasing nonconvex functions
Syarat Perlu atau Cukup F-bounded di dalam Ruang Metrik-α Fuzzy
Get PDFMetrics have an important role in mathematics, both in analysis as well as applications. One of the new concepts of metric space is fuzzy -metric space. This metric space is an expansion of the fuzzy metric space by adding generator. In this paper, we discuss characterization of F-bounded in the fuzzy -metric space. The property of F-bounded is obtained from the compact subset of a given universe set. This characteristic has been discussed by Changqing and Kedian in Hausdorff fuzzy metric spaces. In this paper, the necessary and sufficient conditions are obtained so that the fuzzy -metric space satisfies the properties of F-bounded
Modifikasi Perbaikan Tanah Dasar Tol Semarang–Demak: Metode Vacuum Preloading dengan Prefabricated Vertical Drain
Get PDFThe Semarang-Demak Toll Road Development Project provides information that conditions in these areas were dominated by rice fields and swamps with high groundwater levels. At STA 21+000 to 22+350, the subgrade was very soft to a depth of 24 m, so subgrade improvement needs to be done to eliminate soil compression. The soil improvement method used was Vacuum Preloading with Prefabricated Vertical Drain. The results of the planning showed that the installation of a vacuum pump at the project site has a pressure of 101.28 kPa. The effectiveness of the pump was 80%, making the vacuum pressure 81.02 kPa or the equivalent of 4.89 meters of soil pile. The square PVD installation pattern with a distance of 100 cm was chosen on the basis of consideration of the consolidation time. This design reduces the time it takes for the soil to reach a 90% degree of consolidation, from 256 years to 16 weeks. The Vacuum Preloading method reduces the heap height, as in STA 21+950. This method also creates a subgrade embankment of only 7,767 m
Prediksi Nilai Movement Uji Pullout Soil nailing Proyek Pembangunan Jalan Baru Batas Kota Singaraja-Mengwitani di Provinsi Bali Menggunakan Software Plaxis 2D
Get PDFPengujian soil nailing yang terlalu banyak dilapangan dapat menyebabkan debonding di zona aktif dengan efek yang merugikan dan menimbulkan permasalahan biaya yang cukup besar. Software Plaxis dapat dipergunakan untuk menganalisis dan memprediksi nilai uji pullout soil nails dilapangan. Hal ini cukup efektif untuk proyek long segment yang terdiri dari beberapa paket pekerjaan yang dikerjakan secara bertahap, sehingga rasio uji pullout yang diperoleh dari hasil analisis dapat dipakai untuk paket pekerjaan selanjutnya dengan kondisi dan jenis tanah yang sejenis. Hasil analisis plaxis diolah secara statistik deskriptif dan Anova untuk memperoleh persamaan regresi linier dalam memprediksi nilai uji pullout dilapangan. Dari hasil analisis diperoleh nilai movement (mm) soil nail lebih kecil dari Criteria at VTL sebesar 10.287 mm dan diatas nilai uji pullout dilapangan. Hasil penelitian relevan untuk lokasi objek penelitian pekerjaan soil nailing pada seksi 5, 6 dan seksi selanjutnya pada proyek Pembangunan Jalan Baru Batas Kota Singaraja-Mengwitani di Bal
Preliminary Reflexion on Road Basic Components for Road Infrastructure Preservation Works – a Review
Get PDFRoad Maintenance Program has been changed as Road Preservation Program. This is due to the years of permanent distress on flexible pavement even if yearly maintenance works have been always done. This concept changing give various several important questions. One of these is how the road components should be classified. Finally, it can be noted that classification must be built based on road space and road physical components and the importance level in carrying out the road function. Brief, first the basic road physical components for flowing the traffic, second the road physical components for facilitating basic public facilities that must be placed along the road network. The first components basically consist of pavement, drainage, sign & marking, guard-rail, shoulder. While the second components consist of greenery, and facility, such as for electrical line, telephone line, potable water pipe, gas pipe, etc
Analysis of the Oil and Petrochemical Integrated Refinery Development Plan's environmental impact and its mitigation of public health status
Get PDFDevelopment is a social process that aims to enhance the environment and the quality of communal life. Sustainability happens as a result of the environment serving as a living space and a source of additional value. The following environmental factors must be integrated into a development plan: biogeophysics, social, economic, cultural, and public health. PT PERTAMINA (Corporate Company) in collaboration with Rosneft Oil Company will build and operate a new oil and petrochemical integrated refinery and its supporting facilities. About 27,000 people were hired for the building phase, and about 3,000 for the operation phase. This study aims to lessen the detrimental effects of development plans on public health. This qualitative study is a cross-sectional descriptive investigation of the area surrounding the proposed refinery in East Java Province, Indonesia's Jenu District and Tuban Regency. The study's findings were determined through firsthand observation and a poll of 100 residents who would be impacted by the development plan. The findings show that, in order to prevent environmental disputes, environmental management and monitoring must be carried out
Power Matrix of Spherical and Conical Wavestar Geometry with Linear and Circular Arrangement
Get PDFThis article investigated two different arrays of Wavestar wave energy converter (WEC) with two spherical and conical WEC geometry. The boundary element method and radiation/diffraction theory have been used to evaluate the absorbed power of the Wavestar WECs under different wave heights and periods. For validation of numerical analysis, the heave position and velocity for with and without damping coefficient compare with experimental data. Single Wavestar with spherical and conical geometry under different wave periods were investigated and then two linear and circular arrays for both considering geometries compared with each other. The result shows better performance of a circular array than a linear array for all WECs. Absorbed power by the conical geometry is bigger than the spherical geometry. Besides, the maximum power is belonging to the wave period of 6s and 7s for a circular array while in a linear array the maximum power shift to wave periods of 7s and 8s
Numerical Study of Heat Transfer Characteristics in High Pressure Steam Turbine During Stop Unit Process with Sliding Pressure
Get PDFDuring maintenance of the turbine and its auxiliary equipment, which requires a stop of the turbine oil system equipment and an open turbine casing, the first stage metal temperature requirement must be below 150°C. The normal stop unit method with natural cooling takes about 14 to 17 days. In order to speed up the cooling time to 5 days, a forced cooling turbine is needed using the stop unit method with sliding pressure. The heat transfer that occurs in the high-pressure turbine during the stop unit process with sliding pressure was investigated using the numerical method of CFD simulation. The 2D geometry design was made from high-pressure turbine cutouts images. Then meshing was made. The solver stage and the post-processing stage were set. The simulation was running in a steady state and followed by transients. The validation method was to compare the first stage metal temperature parameter between the actual process and the results of the CFD simulation at a load of 350 MW, then re-simulate it at 500 MW and 645 MW. The stop unit process with sliding pressure starting at 645MW resulted in the best final cooling compared to the stop unit at 500 MW and 350MW loads. By increasing the main steam flow, the resulting cooling increases. By increasing the value of the fluid flow velocity, the Reynolds number increases, so the convection heat coefficient also increases