Materials Science and Engineering Commons^™

Analysis Of Three Phase Controlled Rectifier With The Same Distance Control As Compared To The Same Angle Control, Sudirman S., Sri Kurniati A.

Makara Journal of Technology

Analysis of three phase controlled rectifier with the same distance control as compared to the same angle control. This research aim to compare the firing of the same distance and the same angle control at three phase controlled rectifier with seen generated harmonic at input (AC side). Then calculate of rectifier efficiency and power factor comparison from both the control type. The rectifier use passive filter with resistance 11 ohm and is analysed with program simulation using PSPICE version 7.1. Result of research indicate that use of the same distance control generates the 5th and 7th harmonics, while the same …

The Use Of Red Cabbage’S Anthocyanine Extract As A Photosensitizer On A Dye-Sensitized Nanocrystalline Tio2 Solar Cell, Akhiruddin Maddu, Mahfuddin Zuhri, Irmansyah Irmansyah

Makara Journal of Technology

The use of Red Cabbage’s anthocyanine extract as a photosensitizer on a Dye-Sensitized Nanocrystalline TiO2 Solar Cell. A solid-state dye-sensitized nanocrystalline TiO2 solar cell utilizing anthocyanin extract form red cabbage as photosensitizer was fabricated. The solar cell was formed in sandwich structure, which two electrodes sandwiching polymer electrolyte containing a redox couple (I-/I3 -). One of the electrodes, namely working electrode, TiO2 layer on TCO (transparent conducting oxide) coated glass substrate was sensitized with anthocyanin dye as electron donor in the system. Another electrode was a carbon sheet as a counter electrode. Gel electrolyte based on PEG (polyethylene glycol) containing …

Effect Of Contact Time On Interface Reaction Between Aluminum Silicon (7% And 11%) Alloy And Steel Dies Skd 61, Bambang Suharno, Neni Octapiani Nurhayati, Bustanul Arifin, Sri Harjanto

Makara Journal of Technology

Effect of Contact Time on Interface Reaction between Aluminum Silicon (7% and 11%) Alloy and Steel Dies SKD 61. Die soldering (die sticking) is a defect of metal casting in which molten metal “welds” to the metallic die mold surface during casting process. Die soldering is the result of an interface reaction between the molten aluminum and the die material. Aluminum alloy with 7 and 11% silicon and SKD 61 die steel are the most common melt and die material used in aluminum die casting. This research is done to study the morphology and the characteristics of the formed AlxFeySiz …

Bulk Behavior Of Nanostructured Aluminum: Nanocrystalline Powders Compaction, Canning And Consolidation Via Intense Plastic Straining, Mohamed Mahmoud Hamed Shamma

Archived Theses and Dissertations

No abstract provided.

Guidelines For The Application Of Recycled Concrete Aggregate In The Egyptian Construction Industry, Ahmed Moustafa Essam Aly Kamel

Archived Theses and Dissertations

Construction industry is one of the most important fractions of economy worldwide. This industry consumes enormous amounts of raw materials and produces considerable waste. The optimization of construction material usage not only saves costs but also can significantly contribute towards sustainable development. The concept of recycling the construction and demolition rubble is being addressed in this study as a solution. The recycling of concrete, resulting from both the construction activities and the demolition activities, in order to be used as a source of aggregate is being focused upon in this study. Although the idea of using recycled concrete has been …

Optimal Utilization Of Timber Poles As Structural Members Of Formwork, Ladislaus Lwambuka

Tanzania Journal of Engineering and Technology (TJET)

Timber poles of the type “Mirunda” are commonly used in East Africa as formwork support structures for casting of reinforced concrete slabs, beams and canopies. It is also widely known that the “Mirunda” poles as structural members of formwork are massively used without any structural consideration and guidance. This common practice has resulted into wastage of natural resources and escalated construction costs. This study has attempted to establish the load bearing capacity of randomly selected “Mirunda” poles through laboratory testing. Using an existing construction site as a case study, the results have been used to establish the actual number of …

Final Report: Second Generation Waste Package Design Study, L. S. Armijo, Mano Misra, Piyush Kar

Publications (YM)

The objectives of this project activity are: to review the current YMP baseline environment and establish corrosion test environments representative of the range of dry to intermittently wet conditions expected in the drifts as a function of time. to demonstrate the oxidation and corrosion resistance of A588 weathering steel and reference Alloy 22 samples in the representative dry to intermittently dry conditions. to evaluate backfill and design features to improve the thermal performance analyses of the proposed second-generation waste packages using existing models developed at UNR.

Properties Of Light Transmitting Concrete, Dina Abdel Mohsen Abou Alia

Archived Theses and Dissertations

No abstract provided.

Development Of Knowledge Base Of Concrete Bridge Maintenance System, Bahre Karam

Masters Theses

Bridges are the key elements of any transportation system of a country. Bridges are expensive structures and therefore, it's essential to maintain and repair them on regular basis. Almost one third of the bridges in United States are reported to be in some what deteriorated conditions. This Research presents the development of knowledge base for decision support system for concrete bridges.

During this research various concrete bridge problems are investigated including COlTosion, delamination, cracks, spalling and scour etc. The inspection tools and techniques are addressed in order to identify these problems both for above and below water surface. The various …

Behaviour Of Reinforced Self-Consolidating Concrete Frames, Aly Said, Moncef Nehdi

Civil and Environmental Engineering and Construction Faculty Research

Multi-storey reinforced concrete (RC) structural frames represent some of the most congested structural elements. Placing and consolidating concrete in such structural frames imposes substantial challenges. This offers a unique area of application for self-consolidating concrete (SCC) because of its inherent ability to flow under its own weight and fill congested sections, complicated formwork and hard-to-reach areas. Research is, however, needed to demonstrate the ability of SCC structural frames adequately to resist vertical and lateral loads. In the present study, full-scale 3 m high beam-column joints reinforced as per the Canadian Standards CSA A23·3-94 and ACI-352R-02 were made with normal concrete …

Simple: System Automatic Essay Assessment For Indonesian Language Subject Examination, Anak Agung Putri Ratna, Bagio Budiardjo, Djoko Hartanto

Makara Journal of Technology

SIMPLE: System Automatic Essay Assessment for Indonesian Language Subject Examination. Evaluation of study of a student is a very important aspect of an educational process. Evaluation is aimed at measuring the level of student understanding of the given lecture materials. Measuring student understanding of the course material, using essay-type exam, is generally used as the evaluation tool. In this essay-type exam, the student has to answer questions using sentences, whereby choices of possible answers are not indicated. The student has to answer the questions with his/her sentences. The answers may vary, since it reflects the student’s best thoughts of the …

Utilization Of Bagasse Cellulose For Ethanol Production Through Simultaneous Saccharification And Fermentation By Xylanase, M. Samsuri, Misri Gozan, R. Mardias, M. Baiquni, Heri Hermansyah, Anondho Wijanarko, Bambang Prasetya, M. Nasikin

Makara Journal of Technology

Utilization of Bagasse Cellulose for Ethanol Production through Simultaneous Saccharification and Fermentation by Xylanase. Bagasse is a solid residue from sugar cane process, which is not many use it for some product which have more added value. Bagasse, which is a lignosellulosic material, be able to be use for alternative energy resources like bioethanol or biogas. With renewable energy resources a crisis of energy in Republic of Indonesia could be solved, especially in oil and gas. This research has done the conversion of bagasse to bioethanol with xylanase enzyme. The result show that bagasse contains of 52,7% cellulose, 20% hemicelluloses, …

Biodesulphurization Within Natural Gas In Oil And Gas Field, Sri Astuti Rahayu, M. Fierdaus, Syafrizal Syafrizal, M. Udiharto

Makara Journal of Technology

The presence of sulphur compounds in natural gas can interfere to the quality of natural gas. The decline of combustion gas capacity, metal instrument corrosion in gas piping, and the environmental pollution from gas emission can affect by their presence. Bio-filter is one of the methods that selected to reduce sulphur content in natural gas. A lab scale study of hydrogen sulphide reduction in natural gas had conducted in oil and gas field using bio-filter method. The bio-filter system (±1 L volume) contains an active carbon and thiosulphide medium as a substrate, Thiobacillus thioparus as a single culture of sulphur …

Production Of Medium Chain Length Polyhydroxyalkanoates From Oleic Acid Using Pseudomonas Putida Pga1 By Fed Batch Culture, Sidik Marsudi, Irene K.P. Tan, Seng Neon Gan, K. B. Ramachandran

Makara Journal of Technology

Bacterial polyhydroxyalkanoates (PHAs) are a class of polymers currently receiving much attention because of their potential as renewable and biodegradable plastics. A wide variety of bacteria has been reported to produce PHAs including Pseudomonas strains. These strains are known as versatile medium chain length PHAs (PHAs-mcl) producers using fatty acids as carbon source. Oleic acid was used to produce PHAs-mcl using Pseudomonas putida PGA 1 by continuous feeding of both nitrogen and carbon source, in a fed batch culture. During cell growth, PHAs also accumulated, indicating that PHA production in this organism is growth associated. Residual cell increased until the …

Mechanical Study On Using Of Accr Thermal Conductor At 500 Kv Sutet, Suprihadi Prasetyono

Makara Journal of Technology

Mechanical Study on using of ACCR Thermal Conductor at 500 kV SUTET. At the height of electricity demand increasing recently, circumstance of environment more limited and also expense of high investment, making thermal conductor (conductor thermal resistance) considered to be one of alternative in the electricity transmission bottlenecks. These days it has been developed thermal conductor ACCR (Aluminium Conductor Composite Reinforced) which can operate with temperature up to 240oC, so that making the current carrying capacity being higher than conventional conductor. This research aimed to study load current leading to mechanical characteristic ACCR conductor included tension, length of elongation and …

Construction Of Short-Length High-Rates Ldpc Codes Using Difference Families, Deny Hamdani, Ery Safrianti

Makara Journal of Technology

Low-density parity-check (LDPC) code is linear-block error-correcting code defined by sparse parity-check matrix. It is decoded using the massage-passing algorithm, and in many cases, capable of outperforming turbo code. This paper presents a class of low-density parity-check (LDPC) codes showing good performance with low encoding complexity. The code is constructed using difference families from combinatorial design. The resulting code, which is designed to have short code length and high code rate, can be encoded with low complexity due to its quasi-cyclic structure, and performs well when it is iteratively decoded with the sum-product algorithm. These properties of LDPC code are …

Kinetic Model For Triglyceride Hydrolysis Using Lipase:Review, Heri Hermansyah, A. Wijanarko, Dianursanti Dianursanti, Misri Gozan, Praswasti P. D.K Wulan, Rita Arbianti, Roekmijati W. Soemantojo, Tania Surya Utami, Yuliusman Yuliusman, Momoji Kubo, Naomi Shibasaki Kitakawa, Toshiy Yonemoto

Makara Journal of Technology

Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction …

Sulfonation Of Cptfe Film Grafted Styrene For Proton Exchange Membrane Fuel Cell, Yohan Yohan

Makara Journal of Technology

Sulfonation of cPTFE Film grafted Styrene for Proton Exchange Membrane Fuel Cell. Sulfonation of γ-ray iradiated and styrene-grafted crosslinked polytetrafluoroethylene film (cPTFE-g-S film) have been done. The aim of the research is to make hydropyl membrane as proton exchange membrane fuel cell. Sulfonation was prepared with chlorosulfonic acid in chloroethane under various conditions. The impact of the percent of grafting, the concentration of chlorosulfonic acid, the reaction time,and the reaction temperature on the properties of sulfonated film is examinated. The results show that sulfonation of surface-grafted films is incomplete at room temperature. The increasing of concentration of chlorosulfonic acid and …

Sub-Surface Corrosion Research On Rock Bolt System, Perforated Ss Sheets And Steel Sets For Yucca Mountain Repository, Dhanesh Chandra, Jaak J.K. Daemen

Publications (YM)

Outline

Metallurgical Issues in Underground Repository Reinforcement Support for Nuclear Materials Storage in simulated Yucca Mountain Environment used for Corrosion Issues
Issues related to I-beams (Low Carbon) and Rock Bolts (Med. Carbon)

Experimental

Results

1. Corrosion Tests- Effect of Ionic Concentration (1x,10x,100x), Temperature, concentration and aeration/deaeration effects in YM waters (RB and I-Beam)
2. Hydrogen Permeation Tests
3. Environmentally Assisted Corrosion Tests - Stress Corrosion Cracking/Hydrogen Embrittlement in 100x YM water concentration at Room Temperature and 85oC (I-Beams)

Heating Methods And Detection Limits For Infrared Thermography Inspection Of Fiber-Reinforced Polymer Composites, Jeff R. Brown, H. R. Hamilton

Publications

The use of fiber-reinforced polymer (FRP) composites to strengthen existing civil infrastructure is expanding rapidly. Many FRP systems used to strengthen reinforced concrete are applied using a wet lay-up method in which dry fibers are saturated on site and then applied to the surface. This research investigated using infrared thermography (IRT) as a nondestructive evaluation (NDE) tool for detecting air voids and epoxy-filled holes in FRP systems bonded to a concrete substrate. Four small-scale specimens with FRP thicknesses ranging from 1 to 4 mm (0.04 to 0.16 in.) containing fabricated defects were constructed and inspected in a laboratory setting. Three …

College Of Engineering Senior Design Competition Fall 2006, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …

Biogasoline Production From Palm Oil Via Catalytic Hydrocracking Over Gamma-Alumina Catalyst, Anondho Wijanarko, Dadi Ahmad Mawardi, Mohammad Nasikin

Makara Journal of Technology

Biogasoline Production from Palm Oil Via Catalytic Hydrocracking over Gamma-Alumina Catalyst. Bio gasoline conversion from palm oil is an alternative energy resources method which can be substituted fossil fuel base energy utilization. Previous research resulted that palm oil can be converted into hydrocarbon by catalytic cracking reaction with γ-alumina catalyst. In this research, catalytic cracking reaction of palm oil by γ-alumina catalyst is done in a stirrer batch reactor with the oil/catalyst weight ratio variation of 100:1, 75:1, and 50:1; at suhue variation of 260 to 340oC and reaction time variation of 1 to 2 hour. Post cracking reaction, bio …

A Study On Parallel Computation Tools On Networked Pcs, Heru Suhartanto

Makara Journal of Technology

A Study on Parallel Computation Tools on Networked PCs. Many models for natural phenomena, engineering applications and industries need powerfull computing resources to solve their problems. High Performance Computing resources were introduced by many researchers. This comes in the form of Supercomputers and with operating systems and tools for development such as parallel compiler and its library. However, these resources are expensive for the investation and maintenance, hence people need some alternatives. Many people then introduced parallel distributed computing by using available computing resource such as PCs. Each of these PCs is treated as a processors, hence the cluster of …

Crude Oil Sludge Degradation In Microcosmic Scale: Simple Simulation As Preliminary Study On Land Treatment Bioremediation., Astri Nugroho

Makara Journal of Technology

Crude Oil Sludge Degradation in Microcosmic Scale: Simple Simulation as Preliminary Study on Land Treatment Bioremediation. A study in microcosmic condition has been carried out to evaluate the bacterial hydrocarbonoclastic capability in increasing the oil sludge degradation being mixed with NPK fertilizer as nitrogen resources. Aerobic test was carried out by putting erlenmeyers in a shaker incubator, 120 rpm shaking speed, at 50°C temperature. While 150 days in microcosmic one observation showed that the consortium has the potential to grow up to 50% (v/v) sludge oil load. Maximum growth and maximum growth rate of the consortium occurred in the III …

Determination Of Operation Condition And Product Dimension Accuracy Optimization Of Filament Deposition Modelling On Layer Manufacturing Application, Slamet A. Widyanto, Alva Edy Tontowi, Jamasri Jamasri, Heru Santoso Budi Rochardjo

Makara Journal of Technology

Layer manufacturing process has proven as a process that can produce a high complexity mechanical part. Now, Improvement of LM methods continuously conduct that is aimed to increase precessions and efficiency of these processes. Pressure filament deposition modelling is a form of layer manufacturing process that is designed to produce a plastic part with controlling its semisolid phase. In this research, the equipment of filament depositor is designed and tested to make the product filament deposition. With operation condition observation, the optimal temperature and pressure of deposition process was determined. These experiments used PVC as crystalline material and polypropylene as …

Magnetic Field Effects On Caco3 Precipitation Process In Hard Water, Nelson Saksono, Setijo Bismo, Elsa Krisanti, Azwar Manaf, Roekmijati Widaningrum

Makara Journal of Technology

Magnetic Field Effects on CaCO3 Precipitation Process in Hard Water. Magnetic treatment is applied as physical water treatment for scale prevention especially CaCO3, from hard water in piping equipment by reducing its hardness. Na2CO3 and CaCl2 solution sample was used in to investigate the magnetic fields influence on the formation of particle of CaCO3. By changing the strength of magnetic fields, exposure time and concentration of samples solution, this study presents quantitative results of total scale deposit, total precipitated CaCO3 and morphology of the deposit. This research was run by comparing magnetically and non-magnetically treated samples. The results showed an …

Stress Corrosion Cracking Behavior Of Stainless Steel 304 In The Sulfuric Acid Environment Due To Prestrain, Mohammad Badaruddin, Ahmad Suudi, Arinal Hamni

Makara Journal of Technology

Stress Corrosion Cracking Behavior of Stainless Steel 304 in the Sulfuric Acid Environment Due to Prestrain. The aim of research is to investigate the effect of prestrain on the stress corossion cracking behavior of AISI 304 stainless steel in the sulfuric acid of 10% concentration under the static cantilever loading according to ASTM E-1681 standart. The specimen of 304 Stainless steel was strain up over the yield strength until reaching the uniform strain of 5% and 10% using servopulser UTM 9506 under the displacement control of 0,3 mm/sec. The results of test show that the prestrain of 5% specimen is …

Segmental Sinusoidal Model For Speech Signal Coding, Florentinus Budi Setiawan, Soegijardjo Soegijoko, Sugihartono Sugihartono, Suhartono Tjondronegoro

Makara Journal of Technology

Segmental Sinusoidal Model for Speech Signal Coding. Periodic signal can be decomposed by sinusoidal component with Fourier series. With this characteristic, it can be modeled referring by sinusoidal form. By the sinusoidal model, signal can be quantized in order to encode the speech signal at the lower rate. The recent sinusoidal method is implemented in speech coding. By using this method, a block of the speech signal with 20 ms to 30 ms width is coded based on Fourier series coefficients. The new method proposed is quantization and reconstruction of speech signal by the segmental sinusoidal model. A segment is …

Numerical Modeling Of Concrete Masonry Walls Strengthened By Fiber Reinforced Polymers Under Lateral Loads, Mohamed Salama

Archived Theses and Dissertations

The use of fiber reinforced polymers (FRP) for the seismic retrofit of masonry walls is on the rise. Design formulae are available to estimate the lateral load capacity of the strengthened walls. However, recent experimental data from tests conducted on full scale concrete masonry walls under cyclic lateral loads have shown that these design capacities have not been reached because of the occurrence of other failure modes not accounted for in the design formulae. The limiting failure mode in all test samples referred to in this work was due to premature compression failure of the masonry units at the wall …

Development Of Ferrocement U-Shaped Beams Infilled With Core Materials, Ahmed Mahdy Abdelnaby

Archived Theses and Dissertations

No abstract provided.