Structural Engineering Commons^™

Hazard-Driven Drivers’ Behaviours Towards Vehicle-To-Median Safe Distances, Martha Leni Siregar

Makara Journal of Technology

A median is required for a two-way road to separate traffic from opposing lanes and to prevent head-on collisions. However, studies indicate that medians are also perceived as hazards which need to be avoided during driving. This hazard perception is manifested in drivers’ changing behavior towards various types of medians along the driving lanes inform of their tendency to allow various safe distances to the medians. The Indonesian Highway Capacity Manual (IHCM) does not differentiate between types of medians and the influence on the drivers’ choice of safe margin to the medians. Therefore, this study looks into how the existence …

Construction Of A Novel Method Of Measuring Thermal Conductivity For Nanostructures, Hiroya Ikeda, Shoma Yoshida, Yuhei Suzuki, Veerappan Manimuthu, Faiz Salleh, Fujio Kuwahara, Masaru Shimomura, Kenji Murakami

Makara Journal of Technology

With the aim of characterizing the thermal conduction in a nanometer-scaled materials, we have constructed a novel method on the basis of an ac calorimetric method. In this method, periodic sample heating is performed by light irradiation and the corresponding periodic temperature is detected by infrared irradiative thermometer. This makes us measure the thermal diffusivity out of contact with the objective sample. In the present study, we confirm to measure the thermal diffusivity of bulk Si and Cu by this non-contact method with halogen-lamp irradiation. In determining the thermal diffusivity from the relationship between distance deviation and delay time, the …

The Effects Of The Types Of Milk (Cow, Goat, Soya) And Enzymes (Rennet, Papain, Bromelain) Toward Cheddar Cheese Production, Ariestya Arlene, Anastasia Prima Kristijarti, Ivana Ardelia

Makara Journal of Technology

The objectives of this research are to study the effects of different types of milk and enzymes toward the yield and quality (moisture, ash, protein, fat content, and texture) of cheddar cheese and the interaction between those two variables during the process. The types of milk are cow, goat, and soya milk, while the types of enzymes are rennet, papain, and bromelain enzymes. Regarding the procedure, the milk is first pasteurized before CaCl2 and Lactobacillus lactis that acts as the acidifier starter as much as 0.2% (w/v) and 0.5% of the milk volume are added respectively. The amount of enzyme …

Energy And Exergy Analysis Of Kalina Cycle For The Utilization Of Waste Heat In Brine Water For Indonesian Geothermal Field, Nasruddin Nasruddin, Agus Noor Sidiq, Abdulmajeed Mohamad, Rama Usvika

Makara Journal of Technology

The utilization of waste heat in a power plant system—which would otherwise be released back to the environment—in order to produce additional power increases the efficiency of the system itself. The purpose of this study is to present an energy and exergy analysis of Kalina Cycle System (KCS) 11, which is proposed to be utilized to generate additional electric power from the waste heat contained in geothermal brine water available in the Lahendong Geothermal power plant site in North Sulawesi, Indonesia. A modeling application on energy and exergy system is used to study the design of thermal system which uses …

Vibration Of Steel-Framed Floors Supporting Sensitive Equipment In Hospitals, Research Facilities, And Manufacturing Facilities, Di Liu

Theses and Dissertations--Civil Engineering

Floors have traditionally been designed only for strength and deflection serviceability. As technological advances have been made in medical, scientific and micro-electronics manufacturing, many types of equipment have become sensitive to vibration of the supporting floor. Thus, vibration serviceability has become a routinely evaluated limit state for floors supporting sensitive equipment. Equipment vibration tolerance limits are sometimes expressed as waveform peak acceleration, and are more often expressed as narrowband spectral acceleration, or one-third octave spectral velocity.

Current floor vibration prediction methods, such as those found in the American Institute of Steel Construction Design Guide 11, Floor Vibrations Due to Human …

Influence Of Spatial Variations Of Railroad Track Stiffness And Material Inclusions On Fatigue Life, Celestin Nkundineza

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Railroad transportation is very important for economic growth and effective maintenance is one critical factor for its economic sustainability. The high repetitive forces from a moving railcar induce cyclic stresses that lead to rail bending and potential deterioration due to fatigue crack initiation and propagation. Previous research for prediction of fatigue life has been done under the assumptions of a uniform track bed and a homogeneous rail. However the spatial variation of the track stiffness is expected to increase the maximum stresses in the rail and, therefore, accelerate the fatigue process. The research described in this dissertation is focused on …

Shape Memory Behavior Of Single Crystal And Polycrystalline Ni-Rich Nitihf High Temperature Shape Memory Alloys, Sayed M. Saghaian

Theses and Dissertations--Mechanical and Aerospace Engineering

NiTiHf shape memory alloys have been receiving considerable attention for high temperature and high strength applications since they could have transformation temperatures above 100 °C, shape memory effect under high stress (above 500 MPa) and superelasticity at high temperatures. Moreover, their shape memory properties can be tailored by microstructural engineering. However, NiTiHf alloys have some drawbacks such as low ductility and high work hardening in stress induced martensite transformation region. In order to overcome these limitations, studies have been focused on microstructural engineering by aging, alloying and processing.

Shape memory properties and microstructure of four Ni-rich NiTiHf alloys (Ni50.3Ti29.7Hf20, Ni50.7Ti29.3Hf20, …

Design Of Gan-Based Low-Loss Y-Branch Power Splitter, Retno Wigajatri Purnamaningsih, Irma Saraswati, Nji Raden Poespawati, Elhadj Dogheche

Makara Journal of Technology

We present a Y-branch power splitter design with a multimode section using GaN on Sapphire at telecommunication wavelength. The GaN sample optical properties were also investigated, resulting in a refractive index for the GaN layers nTE=2.289±0.001 and nTM=2.324±0.00. Optimization of the structure parameters for this structure was conducted accurately using BPM methods. The results demonstrated the possibility of realizing a GaN-based Y-branch power splitter for various applications.

Ultra-Wideband Notched Characteristic Fed By Coplanar Waveguide, Rastanto Hadinegoro, Yuli Kurnia Ningsih, Indra Surjati

Makara Journal of Technology

In this paper, a novel Ultra-Wide Band (UWB) notch patch antenna with co-planar waveguide (CPW) fed is presented. This antenna only used one layer and the patch antenna is constructed on the first layer and back to back with CPW fed and bottom part is ground plane. The width notch is used to achieve the UWB characteristic. The results shown that the impedance bandwidth is 1130 MHz (1.662–2.792 GHz) or about 50.7% for VSWR <2.

Development Of The Soekarno–Hatta International Airport Rail Link Project Using The Value Engineering Method: Creating Value For Money, Mohammed Ali Berawi, Bambang Susantono, Suyono Dikun, Tommy Ilyas, Herawati Zetha Rahman, Abdur Rohim Boy Berawi, Teuku Yuri Zagloel, Perdana Miraj, Jade Sjafrecia Petroceany

Makara Journal of Technology

Soekarno–Hatta Airport is the main gateway for international flights to Greater Jakarta. Its accessibility depends on the inter-city and Sedyatmo toll roads, which causes congestion in peak hours, leading to uncertainty about travel times. The Soekarno–Hatta International Airport Rail Link (SHIARL) is proposed as an alternative mass transportation project, which is expected to provide accessibility and mobility for people and goods to and from the airport. Previously, the project was unattractive to private investors as it was technically and financially unfeasible. Therefore, this research aims to improve the feasibility of the Soekarno-Hatta International Airport Rail Link (SHIARL) by using a …

The Mechanical And Tribology Properties Of Sputtered Titanium Aluminum Nitride Coating On The Tungsten Carbide Insert Tool In The Dry Turning Of Tool Steel, Esmar Budi, Mohd. Razali Bin Muhamad, Md. Nizam Bin Abdul Rahman

Makara Journal of Technology

The effect of the sputtering parameters on the mechanical tribology properties of Titanium Aluminum Nitride coating on the tungsten cabide insert tool in the dry turning of tool steel has been investigated. The coating was deposited using a Direct Current magnetron sputtering system with various substrate biases (-79 to -221 V) and nitrogen flow rates (30 to 72 sccm). The dry turning test was carried out on a Computer Numeric Code machine using an optimum cutting parameter setting. The results show that the lowest flank wear (~0.4 mm) was achieved using a Titanium Aluminum Nitride-coated tool that was deposited at …

Continuous Production Of Nanotubes And Carbon Clusters By Use Of The Revolver-Injection-Type Arc Jet Producer, Tetsu Mieno, Naoki Matsumoto, Takahashi Tomie, H. Inoue

Makara Journal of Technology

Efficient and continuous production of fullerenes, single-walled carbon nanotubes (SWNTs), and carbon nano-particles has been developed by the JxB arc jet method, where the Lorentz force of magnetic field jets out gaseous carbon particles to the JxB direction. In order to realize continuous mass production of these carbon clusters, the revolverinjection- type arc jet producer (RIT-AJP) has been developed. Production of fullerenes, endohedral metallo-fullerenes, SWNTs, metal-encapsulated carbon nano particles has been examined.

Analysis Of Vibration Generated By The Rubbing Of Flat Surfaces, Zahrul Fuadi

Makara Journal of Technology

Among the phenomena that occur as a result of contact between two surfaces is friction sound, in which surface roughness is of great importance. In this study, the parameter of contact stiffness is used to explain the frequency characteristic of vibration generated by the rubbing of flat surfaces under a small load. A 3-disk configuration rubbing method was used, which provides a unique characteristic of the system's frequency response function containing specific information about the rubbing vibrations. It is shown that the peak frequency of the rubbing vibration can be explained by using a two-degrees-of-freedom model incorporating the parameter of …

Modified Design Of Pin-On-Ring Tribometer For Hip Joint Prostheses Measurement; Case Study On Salat Activity, Muhammad Khafidh, Jamari Jamari, Sulardjaka Sulardjaka, Mohamad Tauviqirrahman, Emile Van Der Heide

Makara Journal of Technology

Total hip replacement (THR) is one of the most successful orthopedic surgical procedures for replacing a broken hip joint. In THR, wear may occur at the articulating surface of the acetabular cup and the femoral head. In Indonesia, the country with the largest Muslim population in the world, most of the inhabitants do salat (praying) every day. THR users are banned from doing salat for fear it will damage the hip joint prostheses. The previous wear calculation methods on the hip joint prostheses use the gravimetric, coordinate measuring machine (CMM), profiler, and geometric method. The disadvantages of the previous methods …

Endoscopic Application Of A Compact Compound-Eye Camera, Keiichiro Kagawa, Shoji Kawahito

Makara Journal of Technology

A multi-functional compound-eye endoscope enabling multi-spectral imaging and variable field-of-view is presented, which is based on a compact compound-eye camera called TOMBO (thin observation module by bound optics). Narrow-band filters attached to some lenses provide snap-shot multi-band images. Fixed and movable mirrors are introduced to control the field of view, which realizes several observation modes such as three-dimensional shape measurement, wide field-of-view, and close-up observation.

Lateral Load Resistance Of Laminated Veneer Lumber Sengonwooden Joints With Wooden Dowels, Niken Palaeowati, Ali Awaludin, Suprapto Siswosukarto

Makara Journal of Technology

Analytical models for wooden-doweled joints need to be developed. The objective of this research is to determine whether the strength of wooden-doweled joints can be well predicted by equations developed for steel-doweled joints. In this experiment, various connection parameters, such as dowel diameter, species of the wooden dowel, and angle of joints, are studied. The joint specimens are loaded in a quasi-static state with four replications each. A5% offset diameter method is used to determine the lateral load resistance of the tested joints, while the predictions are evaluated by equations given in Indonesian National Standard (SNI) 7973-2013 and the European …

Make Or Buy Analysis Model Based On Tolerance Design To Minimize Manufacturing Cost And Quality Loss, Cucuk Nur Rosyidi, Reza Rizkichani Akbar, Wakhid Ahmad Jauhari

Makara Journal of Technology

In a manufacturing company, manufacturing costs, or component prices, and tolerance will affect the price and the quality of a product. Companies must produce high-quality products with low manufacturing costs in order to keep their products competitive in the market; however, it is difficult to produce a high-quality product with a low manufacturing cost. Companies have difficulties in determining the components to be produced using their own manufacturing facilities (make) or outsourced to their suppliers (buy). Hence, a make or buy analysis is needed to minimize the manufacturing costs and quality loss and to determine the optimum alternative regarding make …

Observation Of Tunneling Effects In Lateral Nanowire Pn Junctions, Sri Purwiyanti, Arief Udhiarto, Daniel Moraru, Takeshi Mizuno, Djoko Hartanto, Michiharu Tabe

Makara Journal of Technology

As electronic device dimensions are continuously reduced, applied bias conditions significantly change and the transport mechanisms must be reconsidered. Tunneling devices are promising for scaled-down electronics because of expected high-speed operation and relatively low bias. In this work, we investigated the tunneling features in silicon-oninsulator lateral nanowire pn junction and pin junction devices. By controlling the substrate voltage, tunneling features can be observed in the electrical characteristics. We found that the minimum substrate voltage required for tunneling to occur in pn junctions is higher as compared with pin junctions. The main cause of these effects relies in the difference between …

Digestibility Of Betung Bamboo Fiber Following Fungal Pretreatment, Widya Fatriasari, Wasrin Syafii, Nyoman J. Wistara, Khaswar Syamsu, Bambang Prasetya

Makara Journal of Technology

This research evaluated the effect of fungal pretreatment of betung bamboo fibers and enzymatic- and microwaveassisted hydrolysis on the reducing sugar yield. The enzymatic hydrolysis of the pretreated biomass was carried out with cellulase and 10 and 20 FPU/g of substrate in a shaking incubator at 50 °C and 150 rpm for 48 h. The sulfuric acid concentration used in the microwave-assisted acid hydrolysis was 1.0, 2.5, and 5%, either with or without the addition of activated carbon. Microwave irradiation (330 Watt) was applied for 5–12.5 min. The yield of reducing sugar was better with the microwave-assisted acid hydrolysis, and …

Argon Ion Irradiation Effect On The Magnetic Properties Of Fe-Al2o3 Nano Granular Film, Setyo Purwanto, Isao Sakamoto

Makara Journal of Technology

We studied the effect of Argon (Ar) ion irradiation on Fe-Al2O3 nanogranular thin film. X-ray diffraction (XRD) patterns show that the ion dose might promote the growth of the Fe2O3 phase from an amorphous phase to a crystalline phase. The magnetic and magnetoresistance properties were investigated using a vibrating sample magnetometer (VSM) and a four point probe (FPP). The results suggest that percolation concentration occurred at the 0.55 Fe volume fraction and with a maximum magnetoresistance (MR) ratio of 3%. The present MR ratio was lower than that of previous results, which might be related to the existence of the …

Adjustable Resonance Frequency Of Rf-Mems Capacitor By Using Comb- Drive Actuators: A Design Approaches, Agus Santoso Tamsir, Sandy Tannu Wijaya, Dato’ Burhanuddin Yeop Majlis

Makara Journal of Technology

The needs of smaller size RF varactor is a must today, and MEMS comes to be the potential one. In this paper we proposed an adjustable resonance RF-MEMS varactor by using comb-drive actuators placing in each side of the square movable plate. In our preliminary simulation, we found that the device can work properly but some constraints comes such as the dominancies of harmonic resonance frequencies that influences into the nominal capacitances. Therefore for the next step of development we have to find out the window of the structural dimension for a certain spans and a certain operating frequencies.

Properties Of Lignin From Oil Palm Empty Fruit Bunch And Its Application For Plywood Adhesive, Lucky Risanto, Euis Hermiati, Yanni Sudiyani

Makara Journal of Technology

Lignin from lignocellulosic biomass is a potential biopolymer for wood adhesive. The aims of this study were to characterize lignin isolated from the black liquor of oil palm empty fruit bunch fiber pretreated with steam explosion in alkaline conditions and to examine the bond quality of aqueous polymer isocyanate (API) adhesive prepared from lignin, natural rubber latex (NRL), and polyvinyl alcohol (PVA) as base polymers with isocyanate crosslinkers. Lignin was precipitated from the black liquor by adding hydrochloric acid; then the precipitate was separated by filtration, thoroughly washed with water up to pH 2 and pH 5, and dried. The …

Electron Emission Characteristics Of Multi-Gated Field Emitters, Hidenori Mimura, Yoichiro Neo, Toru Aoki, Tomoya Yoshida, Masayoshi Nagao

Makara Journal of Technology

We have developed a multi-gated field emitter (FE) such as a quadruple-gated FE with a three-stacked electrode lens and a quintuple-gated FE with a four-stacked electrode lens. Both the FEs can focus the electron beam. However, the quintuple-gated FE has a stronger electron convergence than the quadruple-gated FE, and a beam crossover is clearly observed for the quintuple-gated FE.

The Gaussian Orthogonal Laplacianfaces Modelling In Feature Space For Facial Image Recognition, Arif Muntasa

Makara Journal of Technology

Dimensionality reduction based on appearance has been interesting issue on the face image research fields. Eigenface and Fisherface are linear techniques based on full spectral features, for both Eigenface and Fisherface produce global manifold structure. Inability of them in yielding local manifold structure have been solved by Laplacianfaces and further improved by Orthogonal Laplacianfaces, so it can yield orthogonal feature vectors. However, they have also a weakness, when training set samples have non-linear distribution. To overcome this weakness, feature extraction through data mapping from input to feature space using Gaussian kernel function is proposed. To avoid singularity, the Eigenface decomposition …

Series-Interconnected Plastic Dye-Sensitized Solar Cells Prepared By Low- Temperature Binder-Free Titania Paste, Erlyta Septa Rosa, Lia Muliani, Shobih Shobih, Jojo Hidayat, Brian Yuliarto

Makara Journal of Technology

The aim of this research is to study dye-sensitized solar cells (DSSC). This was implemented on a flexible polyethylene terephthalate (PET) substrate using a mixture of transparent and scattered mesoporous anatase-titania as the electron transport layer for the photoelectrode. This mixture of anatase titania performed a dual function of light scattering and efficient dye absorption. In this study, a porous nano-TiO2 film was prepared on indium tin oxide (ITO) coated polyethylene terephthalate (PET) by using a binder-free titania paste; on it, a DSSC was fabricated. The paste which contained a mixture of TiO2 nanoparticles, acid chloride, and ethanol was printed …

Increased Span Length For The Mgs Long-Span Guardrail System, Nicholas A. Weiland

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Long-span guardrail systems have been recognized as an effective means of shielding low-fill culverts while minimizing construction efforts and limiting culvert damage and repair. The current MGS long-span design provided the capability to span unsupported lengths up to 25 ft (7.6 m) without the use of nested guardrail. The excellent performance of the MGS long-span system in full-scale crash tests suggested that longer span lengths may be possible with the current design.

A detailed analysis of the MGS long-span guardrail system was performed using the finite element software program LS-DYNA^®. It was shown that the MGS long-span design …

Dynamic Characteristic Identification Of Seismic-Excited Multi-Story Buildings Through Response-Only Technique, Agung Budipriyanto, Priyo Suprobo

Makara Journal of Technology

Identifying dynamic characteristics of civil engineering structures is still a challenging task. It intends to assess behavior of the structures under time-dependent loads. This paper discusses a methodology suitable for identifying the characteristics of multi-story buildings using only their measured response under earthquake ground excitations. Appropriateness of technique used for structural identification was corroborated through coherence of the structure’s responses. The methodology was applied for identifying the characteristics of 14-story and 20-story office buildings located in a high seismic region. Responses of these two buildings recorded during three different seismic ground motions were investigated. The buildings’ response spectral densities and …

Performance Evaluation Of An Optimized Floating Breakwater In Oblique Waves With A Higher-Order Boundary Element Method, Faisal Mahmuddin, Masashi Kashiwagi

Makara Journal of Technology

In the previous study, the optimal performance of a two-dimensional (2D) floating breakwater shape was obtained. The performance of this shape was also confirmed with a model experiment in a towing tank. Moreover, the shape’s performance in three dimensions (3D) was investigated in a subsequent study. However, to predict the shape’s performance in a real application more accurately, the shape’s characteristics in oblique waves must also be evaluated. In this study, the performance and characteristics of the model (hydrodynamic forces, body motions, wave elevations, and drift forces) are computed using a higher-order boundary element method (HOBEM). The HOBEM, which is …

Synthesis And Characterization Of Soy-Based Polyurethane Foam With Utilization Of Ethylene Glycol In Polyol, Flora Elvistia Firdaus

Makara Journal of Technology

The use of vegetable oils on replacing petroleum has attracted attention of many researchers. The chemical structure of vegetable oils are different from petrochemicals, so the structure of soybean oil has to be chemically modified through its unsaturated fatty acid chain in triglyceride. A two step process was conducted for the preparation of soy-polyol in designated temperatures; 50 °C, 60 °C, and 70 °C. Ethylene glycol (EG) as co-reagent was taking part in soy-polyol synthesis, and the soy-polyol was used as a sole polyol for polyurethane synthesis. Referred to the previous study, the existence of EG in polyurethane synthesis can …

Performances Of Free-Space Optical Communication System Over Strong Turbulence, Ucuk Darusalam, Purnomo Sidi Priambodo, Harry Sudibyo, Eko Tjipto Rahardjo

Makara Journal of Technology

We report an experimental of free-space optical communication (FSOC) system that use tube propagation simulator (TPS) as the turbulence medium. The FSOC system use wavelength of 1550 nm at the rate transmission of 1000 Mbps and amplified with EDFA at the output of +23 dBm. Index structure of 10-15–10-13 as the representation of atmosphere index turbulences are used for simulation of intensity distribution model or scintillation. The simulation use gammagamma and K model as well. The beam wave propagation models used in simulation are plane wave, spherical wave and Gaussian wave. Spherical wave achieves highest performance via gamma-gamma in strong …