bluuebunny/crossref_metadata_2025 huggingface dataset:
HPV Detection Methods
Authors: Spathis Aris , Kottaridi Christine , Pouliakis Abraham , Archondakis Stavros , Karakitsos Petros
Published: August 2015

Human papilloma viruses (HPVs) have been acknowledged to be the leading risk factor of cervical intra-epithelial lesion creation (CIN) and cervical cancer development (CxCa). Many different techniques have been created and utilized in HPV detection and monitoring with a vast amount of them being commercialized and few of them integrated in official screening strategies. A growing trend for DNA typing of the 14 most commonly accepted high risk HPV types has been introduced, supporting that in many cases molecular testing could replace classic morphologic diagnostic routines, even though DNA detection has lower specificity than other molecular and morphology tests. However, there have been limited attempts in combining data from all different techniques to provide efficient patient triaging schemes, since, apart from the obvious increase of patient cost, the amount of data and its interpretation in patient management has been impossible. Complex computer based clinical support decision systems, many of which are based on artificial intelligence may abolish these limitations.
Analysis of 3D Corpus Callosum Images in the Brains of Autistic Individuals
Authors: Elnakib Ahmed , Casanova Manuel F. , Soliman Ahmed , Gimel'farb Georgy , El-Baz Ayman
Published: August 2015

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that is characterized by abnormalities in behavior and higher cognitive functions. The corpus callosum (CC) is the largest fiber bundle that connects the left and the right cerebral hemispheres of the human brain. Several studies have revealed an abnormal anatomy of the CC in the brains of autistic individuals that associates this neurodevelopmental condition with impaired communication between the hemispheres. In this chapter, we develop a framework to analyze the CC of autistic individuals in order to provide a diagnostic tool for autism. The key advantage of this approach is the development of a cylindrical mapping that offers simplified coordinates for comparing the brains of autistic individuals and neurotypicals. Experimental results showed significant differences (at the 95% confidence level) between 17 normal and 17 autistic subjects in four anatomical divisions, i.e. splenium, rostrum, genu, and body of their CCs. Moreover, the initial centerline-based shape analysis of the CC documented a promising supplement to the current techniques for diagnosing autism.
Trends of ECG Analysis and Diagnosis
Authors: Majumder Swanirbhar , Pal Saurabh
Published: August 2015

Any biomedical signal has the specialty in terms of the remoteness and nature of their source as an advantage over other natural signals. The analysis of biomedical signal plays a significant role in medical, and to be exact cardiological decision making, provided, the subject information is accurate and reliable. Normally experienced and trained medical practitioners, are known to study and know them better, but in this age of technology computerized expert system are better for long term continuous monitoring and automatic decision making. This led to evolution of biomedical engineering as a separate wing where parts of engineering under automatic signal processing and analysis studies are done. ECG being the most vital physiological signal, its acquisition technique, noise and artifacts elimination methodologies are discussed in this chapter. A brief description on ECG and its usage as biometric and analysis of Atrial Fibrillation is presented.
What's Memory All About?
Authors: Caixinha Aníbal , Alexandre Isabel Machado
Published: August 2015

Dementia is, unfortunately, a well-known problem of nowadays, product of a set of generational transformations and a result of better life conditions. There are different kinds of dementia but Alzheimer is the one with predominance. Memory is the key factor in this type of illness and it is nuclear to understand how it is constructed to hypothesise and try to determine how it degenerates. In this chapter, memory structures are presented as a starting point of the research and then through the use of narrative intelligence we devise a method to present small excerpts of patient's history and simultaneously illness progression is evaluated. To do this, a small prototype of MEM+ has been developed, and for its development a participatory design was conducted. With this approach, we aim to devise the right application to be used by the patients themselves and by their caregivers. During this stage of the project special attention was paid to usability issues, and some adaptations made to better the human computer interaction.
Home Care Systems for the Management of Patients with Mental Disorders
Authors: Haritou Maria , Koutsouris Dimitris
Published: August 2015

This chapter provides an overview of the various aspects involved in the development of a home care system for the management of dementia, based on the experience of ALADDIN implementation. The ALADDIN platform aims to provide a trustworthy and reliable solution supporting patients and their informal carers in the management of the disease from home. Based on a set of monitoring parameters and measuring scales feeding a reconfigurable Event Detection mechanism used for Risk Assessment and Analysis, the system aims to early detect symptoms predicting decline, avoid emergencies and secondary effects and thus prolong the period that patients can remain safely cared at home. Informal carers are also monitored by the system whereas additional features supporting networking, education and cognitive stimulation are also integrated along with decision support tools for the clinicians. It is an open, secure, interoperable, integrated IT-solution designed according to Service Oriented Architecture principles and credible methodologies for patient follow-up, risk detection and adaptive care.
Assessment of Chronic Health Care through an Internet Consensus Tool
Authors: Monguet Josep Ma. , Trejo Alex , Martí Tino , Espallargues Mireia , Serra-Sutton Vicky , Escarrabill Joan
Published: August 2015

“Health Consensus for the Assessment of Chronic Care Programs” (HC-ACP) is an internet based application created to promote and facilitate the participation of health professionals in the definition of a set of indicators for the assessment of chronic care and management of areas of improvement in this field. The first prototype of the application has been applied twice, first in the region of Catalonia, and in a second project in the context of the whole Spanish Health System. HC-ACP has collected contributions from more than 800 health professionals from around Spain including profiles in the fields of management, health care professional, health planning and quality assessment, allowing sharing and aggregate knowledge and clinical experience from a wide range of points of view. After a process of literature review and panel meetings with professionals who proposed a wide list of indicators, the HC-ACP application was used to select a minimum set of indicators following a participative process based on Health Consensus, an online Real Time Delphi method. The first part of this chapter is devoted to expose paradigms that define the interdisciplinary research field of the method, the second part of the chapter presents the Health Consensus method, and finally the third part exposes a detailed description of the HC-ACP application and the followed process. Besides the relevance and utility of the Health Consensus method, the action-research conducted to build the application proves the efficiency and effectiveness of getting health professionals really involved in the processes of defining the models to assess the healthcare system. The online method proposed has been accepted by participants who have expressed high levels of satisfaction during the participation process.
Personal Health Systems for Diabetes Management, Early Diagnosis and Prevention
Authors: Zarkogianni Konstantia , Nikita Konstantina S.
Published: August 2015

This chapter aims at the presentation and comparative assessment of tools and methodologies used for the development of Personal Health Systems (PHSs) for diabetes management, early diagnosis and prevention. Medical decision support systems such as glucose prediction models, risk assessment models for long-term diabetes complications, models for early diagnosis of diabetes and closed-loop glucose controllers along with integrated systems for diabetes management are described. The outcomes of a wide range of research studies demonstrate the feasibility of providing safe, reliable and cost-effective solutions towards improving patients' quality of life through the application of PHSs. Specific limitations that prevent these systems from being fully adopted in clinical practice are highlighted, while challenges and future research directions are summarized.
The Conceptual and Architectural Design of an Intelligent Intrusion Detection System
Authors: Dhakar Mradul , Tiwari Akhilesh
Published: August 2015

The tremendous work in the field of security has made enormous efforts towards the ascertainment of innovative ideas along with their practical applicability. These motivated the security agencies to adopt them practically. But adequate remedies are not accomplished yet due to the enhanced technological aspects even in the unlawful communities. These communities have become a major concern for the security agencies and can be considered as unaddressed issue. This concern led to the introduction of Intrusion Detection Systems (IDSs). The IDS is a means for detecting the intrusive events concealed among the activities of normal users. Additionally, such systems also provide necessary assistance in preventing future intrusions. The present chapter focuses on improving the performance of the IDS in order to meet the contemporary progression by proposing a system that is able to achieve a system that is effective, adaptive and intelligent in nature and is able to remarkably detect intrusions. In order to accomplish the desired system, the chapter involves development of intelligent IDS.
Agents for Intrusion Detection in MANET
Authors: Mechtri Leila , Tolba Fatiha Djemili , Ghanemi Salim
Published: August 2015

Mobile Ad-hoc NETworks (MANETs) are believed to be highly vulnerable to security threats due to the numerous constraints they present such as: the absence of a fixed infrastructure, the dynamic topology change, their dependence on cooperative communication, the unreliability of wireless links and most importantly the absence of a clear line of defense. Since intrusion detection and agent technology proved to offer several potential advantages, there has been a great tendency for using agents to build optimal, adaptive and comprehensive intrusion detection systems to fit MANET security requirements. This chapter presents a survey and analysis of the work that has been recently done for the deployment of agent technology in the area of MANET intrusion detection. In particular, recent advances in that field in terms of existing frameworks, architectures and implementations as well as a discussion of the obtained advantages in addition to the potentially introduced vulnerabilities are presented.
Applications of Digital Signature Certificates for Online Information Security
Authors: Banday Mohammad Tariq
Published: August 2015

Information security has been the focus of research since decades; however, with the advent of Internet and its vast growth, online information security research has become recurrent. Novel methods, techniques, protocols, and procedures are continuously developed to secure information from growing threats. Digital signature certificates, currently offers one of the most trusted solutions to achieve CIA-trio for online information. This chapter discusses online information security through cryptography. It explains digital signature certificates; their benefits, the underlying standards, involved techniques, procedures, algorithms, processes, structure, management, formats, and illustration of their working. It highlights the potential of digital signatures and certificates in information security across different devices, services, and applications. It introduces a few useful tools to learn, train, and implement digital signature certificates.
Cryptomodules in Wireless Networks Using Biometric Authentication
Authors: Drahanský Martin , Hanáček Petr , Zbořil František , Henzl Martin , Zbořil František V. , Yim Jaegeol , Shim Kyubark
Published: August 2015

This chapter shows how cryptomodules can increase security of wireless sensor network and possibilities of biometric authentication against a node or the whole network. For secure operation of a wireless sensor network, security objectives such as confidentiality, integrity, and authentication must be implemented. These security objectives typically employ cryptography, therefore sensor nodes should be able to compute cryptographic algorithms and provide secure tamper-resistant storage for cryptographic keys. Use of dedicated secure hardware for this purpose and security threats are discussed. Two scenarios where the biometric authentication would be appreciated are introduced – smart home and storehouse with medicaments. Biometric generation of cryptographic keys, biometric authentication in wireless network and possible attacks on biometrics are presented. When designing and verifying communication protocols using informal techniques, some security errors may remain undetected. Formal verification methods that provide a systematic way of finding protocol flaws are discussed.
Improving the Security of Digital Images in Hadamard Transform Domain Using Digital Watermarking
Authors: Santhi V. , Acharjya D. P.
Published: August 2015

In recent days, due to the advancement in technology there are increasing numbers of threats to multimedia data which are floating around in the Internet especially in the form of image data. Many methods exist to provide security for digital images but transform domain based digital watermarking could be considered as a promising method. Many transformation techniques are used to insert watermark in cover data, but this chapter deals with watermarking approaches in Hadamard transform domain. In traditional watermarking approaches the scaling parameter is empirically considered for inserting watermark but to maintain the quality of underlying cover images it needs to be calculated based on the content of the cover images. In order to make the watermarking algorithm completely automated the embedding and scaling parameters are calculated using the content of cover images. Many methods are existing for calculating scaling parameter adaptively but this chapter discusses various approaches using computational intelligence to arrive at optimum value of scaling and embedding parameters.
Burst Strength of Glass Fibre/Epoxy Composite Pipes Subjected to Impact Loading
Authors: Hawa A. , Abdul Majid M.S. , Afendi Mohd , Haslan M. , Pranesh Krishnan , Amin N.A.M.
Published: August 2015

The main objective of this experimental study was to investigate the effects of low velocity impact loading on the pressure bearing capacity of the E-glass/epoxy composite pipes. The pipes were produced by the conventional filament winding technique comprises of six axisymmetric layers with (±55°)3 winding angles. The specimens were impacted at three different energy levels which are 5 J, 7.5 J, and 10 J using an instrumented drop weight impact testing machine (IMATEK IM10). The samples were then filled with water and subjected to burst test until distinct leakage failure is observed. The results indicate that the peak force and contact time increases with increased of impact energy. For impacted samples, the pressure tests show that the burst strength of the pipes decreases with increase in energy levels during impact loading. During the burst tests, several damage types named leakage and eruption were observed.
Effect of Porosity on Circle Grid Perforated Plate Performance as a Static Mixer in Laminar Flow
Authors: Manshoor Bukhari , Mat Loddin M.Z. , Khalid Amir , Zaman Izzuddin Bin
Published: August 2015

Mixing is one of the important processes to the many industries. Fluid mixing process typically involves three phases of fluid in the form of liquids, gases and solids. To obtain a desired type of mixing, one of the devices that can be use is a static mixer. In this study, a perforated plate static mixer with circle grid fractal design with two grades of porosity which are 50% and 75% will introduce. The purpose of implementing the two grades porosity of perforated plate in this study is to determine a performance of the two static mixers. In order to achieve the objective, the simulations of mixing fluid were carried out by using ANSYS CFX software. The simulation was carrying out primarily in cylindrical pipe with insertions of circle grid perforated plate. Three levels of laminar flow had been used which is Reynolds numbers (Re) equal to 100, 200 and 400. The performance of circle grid perforated plate static mixer will be evaluated by determining the Coefficient of Variation (COV). The simulation results also were compared in term of homogeneity level of mixing fluids to the Kenics static mixer. Based on the simulation results, the value of COV at selected plane in pipeline simulated for Kenics static mixer and the two grades porosity of perforated plate at Re = 400 are 0.000703, 0.0247and 0.00427 respectively. Since the values of COV between 0.01 and 0.05 are a reasonable target for many industry applications, the results for new approach of static mixer represent completely homogeneous mixing fluid for this application. Definitely this new approach of circle grid perforated plate with fractal design gave better results because of lower number of inserts and simple design of static mixer.
RotoPower – A Real Time Electricity Source Based on Rotational Motion
Authors: Rajesh Kannan Megalingam , Abilash Baburaj , Karthik Sreekanthan , Anoop Mattathil , Anriudh H.
Published: August 2015

Sewing is one of the oldest textile arts which are still popular among the masses of India. Beyond being an art work, sewing serves as a source of livelihood for millions of people. In modern India the major part of the sewing industry is confined to the rural villages spread across the north and the north eastern states of India. Most of these villages are still to receive electricity and those of whom have, are sustaining on the verge of energy poverty. The operation of a sewing machine can be harnessed to produce electricity for small scale purposes. This can be used for charging batteries, mobile phones, lamps, emergency lights. The rotational aspect of the sewing machine wheel can be used to generate power. Power generation is facilitated by using an Alternator. The usage of an Alternator over a DC Motor or Dynamo has added advantages which are described in detail in due course. This paper is intended to present a method to generate power by effectively harnessing the rotational capability of a sewing machine wheel. The paper also deals with the advantages of using an alternator over other electricity generating devices.
An EMG Study for the Application of New Harvesting Oil Palm Fruit Device to Reduce MSDs
Authors: Md Kawi Roejhan , Razali Z.B. , Mansor Muhammad Naufal , Asyraf C.D.M.
Published: August 2015

Farm workers in the Oil Palm industry in Malaysia are extremely exposed to the risk of musculoskeletal disorders (MSDs) which is directly affected to the production outputs. This paper is to discuss the way to reduce the MSDs biomechanical load by using a new design of ergonomic palm oil fruit harvesting device. According to the observation, manual harvesting process by using conventional device or device was highly risk to undergo MSDs due to repetitive awkward posture. Thus, new device is proposed for reducing the effect of MSDs. Electromyography (EMG) evaluation was conducted to determine the reliability and the efficiency of the proposed method to reduce the risk of MSDs. Results of EMG show that the using of the proposed device provides less pain compare to the conventional device.
Reverse Engineering and Structural Analysis of Radiator Fan Blades
Authors: Vijayaganapathy D. , Balasubramanaim K.
Published: August 2015

The function of the fan is to reduce heat in the radiator where hot cooling liquid is circulated. The radiator fan blades are made up of various materials nowadays and the legacy material used is steel. This paper presents the static analysis of the radiator fan and at the outcome we analyze the failure of the entire blade taking into design consideration. The analysis of the radiator fan is executed to different types of materials to check and evaluate the material and process conditions which withstand the dynamic and structural loads. In the paper design of the blade is done through reverse engineering. The static analysis is done using ANSYS where the 3D solid model of the radiator fan is considered for structural analysis. The various loads and properties and applied through the entire length of the radiator fan. The analysis leads us to proposal of suitable material to withstand all the loads. The Fiber Reinforced Plastic (FRP) material is tested and considered.
Influence of Different Anvil Back Plates on Heat Dissipation Velocity of the Micro-Friction Stir Welding Process
Authors: Chu Wan Shun , Binti Yusof Farazila
Published: August 2015

The objective of this study is to investigate effects of different anvil back plates on heat dissipation velocity of the micro-friction stir welding (micro-FSW or) process. For this purpose, temperature field simulations are conducted for the micro-friction stir welding of AA5083-H323 aluminum alloy thin sheets by using the ceramic anvil back plate and conventional steel anvil back plate, respectively. Comparing the obtained two temperature fields, it is found that the ceramic anvil back plate significantly decreases the heat dissipation velocity of the micro-FSW process.
Investigation of Flexure Strength on Carbon Fiber Reinforced Epoxy (CFRE) for Aircraft Panel
Authors: Syayuthi A.R. , Haftirman Haftirman , Basaruddin K.S. , Abdul Manan M.S.
Published: August 2015

Failure behaviour of aircraft sandwich panels under bending load has been investigated in this study. Three-points bending test was performed to the specimens with various span-to-thickness (S/d) ratios 32, 40, and 60. Testing method and dimension of specimens were adhering to the American Society for Testing and Materials (ASTM) D-790M. Deflection and energy absorption of the sandwich panels was characterized by specific span-to-thickness (S/d) ratios. It was found that specimen with S/d of 40 has the steepest slope in stress-strain curve and specimen with S/d of 32 has the highest flexure strength, 831MPa. The flexure strength decreases with the increasing of span-to-thickness ratio. The result shows that the increasing of the span-to-thickness ratio increased the crack length at the lowest maximum bending stress, 636 MPa. The results suggest that the performance of the Carbon Fiber Reinforced Epoxy (CFRE) composites is strongly influenced by the crack length.
Determining the Accuracy of the Life Determination Analysis for Low Carbon Steel
Authors: Mansor Nor Izan Izura , Abdullah Shahrum , Ariffin Ahmad K. , Mahmud M.
Published: August 2015

The objective of this paper is to obtain fatigue properties of API X65 steel using the stress life (S-N) approached. In this method S-N curve was established by relating the applied load and the number of cycles to failure. The sets of data were successfully constructed within the range of high and low cycle domains. The fully reversed loading was employed to generate the most severe damage condition. The experiment data lies approximately within correlation boundaries of 1:2 and 2:1. The mean square error was performed to evaluate the goodness of experiment to the simulated data. Therefore, with a 21% of accuracy it was concluded the presented data taken from actual measurements can be used for life prediction of X65 steel.
Microstructure of AA7075 Based Composite by Accumulative Roll Bonding Process
Authors: Pramono Agus , Kollo Lauri , Veinthal Renno
Published: August 2015

Accumulative Roll Bonding (ARB) is a Severe Plastic Deformation (SPD) process invented in order to fabricate ultrafine grained materials. Aluminum Alloy series 7075 (AA7075) is a metal as a matrix reinforced by Alumina Nanofiber (ANF). In the development of advanced materials, AA7075/ANF composite metal is very suitable if it is processed by ARB, due to the combination of high style roll that is capable of producing material properties better. Hardness of AA77075 without reinforcement reached 128.3 Hv10. The additions of ANF on AA7075 reduce the hardness of 103.2 Hv10. This is due to large deformation of high load on the ARB which results in decrease levels of precipitates as well as lower density and reduction in the average grain size.
The Influence of Alkali Treatments on Tensile Strength and Surface Morphology of Cellulose Microfibrils
Authors: Sosiati Harini , Pratiwi Henny , Wijayanti Dwi Astuti , Soekrisno Soekrisno
Published: August 2015

Cellulose microfibrils were extracted from kenaf fiber by alkali treatments under various conditions to further characterize their properties and verify the factors which induce fiber degradation. Before treatment, the surface morphologies of the base, middle and tip of the raw fiber were observed. The tensile strength of untreated and treated fibers was measured with a universal tensile machine (UTM). Changes in surface morphologies of cellulose microfibrils were characterized by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) spectroscopy was used to characterize the functional group related to cellulosic and non-cellulosic phases. Surface morphology of the middle of the fiber was denser and stronger than that of the periphery and therefore used to define an initial condition of fiber specimen. Alkali treatment in 6% NaOH at room temperature for 1 h increased the tensile strength of the microfibril; 9% NaOH at 100°C for 2 h results in a marked decrease. Damage to the fiber surface and loss of crystallinity were associated with decreased tensile strength.
Numerical Investigation of the Plastic Contact Deformation between Hemispheres: Variation of Radii Ratio and Normal Loads
Authors: Ismail Rifky , Prasojo T. , Tauviqirrahman Mohammad , Jamari J. , Schipper Dirk Jan
Published: August 2015

Investigation of local plastic deformation between rough surfaces in mechanical components such as gears, camshaft and bearings is very important. Contact between real surfaces occurs at the summits of the highest asperities which vary in height and radius. The plastic deformation of the contact between two asperities was studied in this paper. Asperity contact was modelled as a contact between hemispheres. The commercial finite element software, ABAQUS, was employed to perform the numerical contact analysis of the elastic perfectly-plastic deforming hemispheres with the ratios of radii (R2/R1) from 1 to 7. Normal loads of 5000 N, 8000 N and 11000 N were applied to the frictionless contact of the hemispheres. It was shown that the plastic deformation ratio (ωp1/ωp2) decreases as the radii ratio increases. The higher normal load showed a lower plastic deformation ratio for high radii ratio. The results indicate that the radii ratio contributes to the severity of the plastic deformation and the total displacement of the contacting asperities.
Preliminary Study on the Biocompatibility of Stainless Steel 316L and UHMWPE Material
Authors: Anwar Iwan Budiwan , Saputra Eko , Jamari J. , van der Heide Emile
Published: August 2015

Stainless steel AISI 316L (SS316L) and ultra-high molecular weight polyethylene (UHMWPE) are widely used materials for artificial hip joint components. The SS316L material is typically used for the acetabular cup, femoral head and the stem, while the UHMWPE material is used for the acetabular liner in an artificial hip joint. The aim of this work is to study the biocompatibility of SS316L and UHMWPE materials by implanting and installing these materials in the tissues of rabbits. The tissues around the implants were examined after eight weeks of the installment. Results showed that the reaction of the rabbit tissues around the implants was positive. It was concluded that the SS316L and the UHMWPE materials are biocompatible and the applications of these materials for implants seems conceivable.
A Bipolar Artificial Hip Joint Design for Contact Impingement Reduction
Authors: Saputra Eko , Anwar Iwan Budiwan , Jamari J. , van der Heide Emile
Published: August 2015

The acetabular liner of an artificial hip joint (AHJ) is easily damaged locally in case of impingement, i.e. in case of contact of the liner wall with the stem neck, especially when it is made from relatively soft material such as ultra high molecular weight polyethylene (UHMWPE). Frequent impingement will severely damage the acetabular liner, requiring replacement of the AHJ. The aim of this study is to reduce AHJ impingement for specific combinations of flexion, internal rotation, and adduction of the thigh, by optimizing the design of the AHJ. The presented new design is based on modifying a conventional AHJ into a bipolar version with a higher free range of motion (RoM). Results show that the proposed design is able to prevent impingement for RoM. The latter range of motion corresponds well with the requirements of Shalat.
Synthesis of Biodegradable Plastic Films from Oil Palm Empty Fruit Bunch Cellulose
Authors: Herawan Tjahjono , Rivani Meta
Published: August 2015

Cellulose from Oil Palm Empty Fruit Bunch (OPEFB) has a possibility to be converted into biodegradable plastic cellulose ester due to its huge availability. Cellulose ester has thermoplastic properties and is widely used in many polymer applications. This paper describes about esterification OPEFB cellulose with long chain fatty acid chloride in homogeneous system. Some different molar ratios of anhydroglucose unit (AGU) to fatty acid chloride were applied to observe cellulose ester with regards to weight increase percentage (%WIP), recovery yield (%RY) and degree of substitution (DS). Others characteristics were also determined, such as solubility and tensile strength of film casting (MPa). Cellulose palmitate, cellulose laurate and cellulose oleate were successfully produced from OPEFB cellulose. The study found that there is a correlation between type and molar ratio of fatty acid chloride. In an identical reaction condition, a longer fatty acid chlorides and a higher ratio molar AGU to fatty acid chloride produce cellulose ester with high WPI except cellulose oleate ester.
Sputtering of Titanium in Co-Cr-Mo Alloys for Orthopedic Implant Materials
Authors: Sulistioso G.S. , Bandriyana Bernardus , Siswanto Bambang
Published: August 2015

Sputtering process of titanium have been carried out to improve the hardness and wear resistance of the Co-Cr-Mo alloy for orthopedic implant material. The CoCrMo alloy was synthesized by melting process with addition of Cr2N powder into melts to define the high Cr and high N contents. The solid Ti target was sputtered by argon gas and coated into the CoCrMo substrate at temperature of 200 °C for 2, and 4 hours in the nitrogen gas environment. Characterization was performed to the specimen of CoCrMo ingot before and after sputtering process by microstructure, hardness, corrosion and wear resistance tests. Synthesis of the alloy produced dendrite structure ingot. The hardness, the wear resistance and the corrosion resistance in the simulation body fluid increased after sputtering process due to the formation of oxide thin layer in surface of the alloy.
Comparison between Conventional and Ultrasonic Preparation of Chitosan from Shrimp Shells Waste
Authors: Arifin Zainal , Irawan D.
Published: August 2015

Chitosan is a natural biopolymer derived by deacetylation of chitin from the two main sources of crustaceans, shrimp and crabs. Chitosan, which is soluble in acidic solutions, is used in many applications (biomedical/pharmaceutical, water engineering, food, cosmetics). There have been many researchers who have developed a process of deacetylation of chitin from shrimp shells waste by thermochemical or enzymatic methods. However, application of ultrasonic irradiation for chitin deacetylation has received little attention. In this work, the deacetylation of chitin with concentrated sodium hydroxide was performed using ultrasound irradiation (80 W, 42 kHz). The reaction time and degree of deacetylation were compared with conventional process. Results showed that under the same condition, the degree of deacetylation was similar. However, the use of ultrasonic irradiation decreased the reaction time, showing that this method may be a promising alternative method to the conventional method.
Synthesis of Isopropyl Esters from Jatropha Curcas Oil at Short Time Reaction
Authors: Irwan Muh. , Saidi Hamdani , Rahman M.A.
Published: August 2015

The searching of environmentally friendly materials that have potential to replacement mineral oil is currently being considered a top priority research topic in the fuel and energy sector. This paper presents the influence of ultrasound-assisted transesterification of jatropha oil to isopropyl ester and the optimum condition. The transesterification was performed by using isopropyl alcohol as solvent in the presence of ultrasound operating frequency constant at 35 kHz. The isopropyl ester content of product was 97.80 % under the the reaction temperature of 60 °C, isopropyl alcohol to jatropha oil molar ratio of 8 : 1 within the reaction time of 15 minutes.
The Influence of ZnO Components on the Photocatalytic Activity of Fe3O4-CuO-ZnO Nanocomposites
Authors: Susanto Iqriah Kalim , Taufik Ardiansyah , Saleh Rosari
Published: August 2015

Nanocomposite Fe3O4-CuO-ZnO with different molar ratio of Fe3O4:CuO:ZnO were synthesized using sol-gel method and characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning electron microscope, UV-visible diffuse reflectance spectroscopy and vibrating sample magnetometer. The characterization results manifested that the combination of Fe3O4, CuO and ZnO nanoparticles was successful. The photocatalytic activity of nanocomposite with the molar ratio of 1:1:5 was more effective in the degradation of methylene blue under UV light irradiation than pure Fe3O4, CuO, ZnO. The role of photoactive species involved in the photocatalytic reaction was studied and found that holes play the most important role in photodegradation of methylene blue.
Fabrication of PVA Fibers Loaded with Fe3O4 Nano Particles Using Electrospinner
Authors: Harsojo Harsojo , Waluyo Anita Fira , Sosiati Harini , Triyana Kuwat
Published: August 2015

It has been studied the fabrication of a sheet made of polyvinyl alcohol (PVA) fibers loaded with Fe3O4 nanomagnetic materials using an electrospinning technique. The solution for the electrospinner was prepared by stirring nano powder of Fe3O4 with a solution of 10% PVA in water at room temperature. The electrospinning process was done under fixed of 15 kV DC voltage, using 12 cm distance between the electrodes, and using a syringe needle having a diameter of 0.4 mm. The morphology of fibers was tested using scanning electron microscope (SEM), while the size of particles was tested using transmission electron microscope (TEM). Moreover, the crystallinity of fibers was tested using Laue and x-ray diffraction, while the magnetic moment was tested using a vibrating sample magnetometer (VSM). The result shows that the PVA sheet composing of fibers having a diameter in the range of 130 mm to 250 mm, accommodating Fe3O4 nano particles in the range of 15 mm to 25 mm, indicating a partial superparamagnetic property.
A Symbolic Computation of the Gravity Effect on the Electromagnetic Properties of Materials
Authors: Hermanto Arief
Published: August 2015

In principle gravity will affect everything. Although practically negligible it is legitimate to inquire the effect of gravity on the electromagnetic properties of materials which can be expressed as the relation between (d,b) fields (electric displacement and magnetic induction) with the (e,h) fields (electric and magnetic field strength). A sample of material in a weak gravitational field is equivalent with placing the sample in an accelerating reference field (which is the statement of the equivalence principle). By using the relation between the accelerating frame with the inertial frame we can compute the electromagnetic properties with the assistance of CAS (Computer Algebra System) Reduce due to the tedious algebraic manipulations needed to accomplish the task. The linear and isotropic relation in inertial frame (free of gravity), although still linear, becomes unisotropic and mixed up between electric and magnetic fields.
Synthesis and Characterization of Al2O3 Nanoparticles and Water-Al2O3  Nanofluids for Nuclear Reactor Coolant
Authors: Syarif Dani Gustaman , Prajitno Djoko Hadi
Published: August 2015

A study on synthesis and characterization of Al2O3 nanoparticles for water-Al2O3 nanofluids as an alternative nuclear coolant has been done. The Al2O3 nanoparticles were synthesized from AlCl3 using sol gel method utilizing sugar as chelating agent. The Al2O3 nanoparticles were mixed with water to produce nanofluids. XRD data showed that the Al2O3 nanoparticles crystallize in gamma alumina with crystallite size of 5.5 nm (Debye Scherrer method). Surface area of the Al2O3 nanoparticles was 90 m2/gram. Data of TEM showed that the particle size was smaller than 10 nm and the nanoparticle formed agglomerate with size of 60-100 nm. According to zeta potential data, the nanofluids were stable at pH 2.6-7.5 with zeta potential of 28-51 mV. The height of the nanofluid surface decreased about 20 % after 6 days. The thermal conductivity of the water-Al2O3 nanofluids produced in this study increased about 2.4-9.7 % compared to that of water.
Effect of the Concentration of Zinc Oxide Nano Fluid for Enhancing the Performance of Stirling Engine
Authors: Suyitno Suyitno , Dwi Prija Thahjana Danardono , Sutarmo Sutarmo , Hadi Syamsul , Emhemed Alfaitory
Published: August 2015

The development of nano fluid is very promising as a new fluid because it shows superior properties. However, the distinctive properties of the fluid depend on the concentration of nano material besides its designation also needs to be reviewed. Therefore, this study aims to develop the ZnO-based nanofluid for improving the performance of Stirling engine. The nano fluids were prepared by suspending nanorod ZnO into ethanol with various concentrations. Physical properties of the nano fluid such as density, thermal conductivity, viscosity, and specific heat were measured. Meanwhile, the performance of the Stirling engine using ZnO-based nano fluid was investigated including power, torque, and efficiency. The results showed that the performance of the Stirling engine increased along with the increase of the concentration of ZnO nano fluid to 5% and then decreased above this point. The addition of nano fluid up to a concentration of 5% was able to produce the efficiency of Stirling engine at 3.86% or an increase by 51.7% when compared with the previous Stirling engine.
Thermal Characterization of Bacterial Cellulose/Polyvinyl Alcohol Nanocomposite
Authors: Abidin Akhmad Zainal , Graha Hafis Pratama Rendra
Published: August 2015

Bacterial cellulose (BC) is a natural polymer which can be produced from various substrates easily found in Indonesia. Bacterial cellulose is believed to be a promising and cost effective bone scaffold in which a bone regeneration rate enhanced so the healing process is faster. In this experiment, Bacterial Cellulose (BC)/ Polyvin y l Alcohol (PVA) nanocomposite was made to give a further improvement in the properties. This nanocomposite was made thorough BC biosynthesis in Gluconacetobacter xylinus fermentation medium that was modified by addition of PVA. The PVA concentrations were varied as 0, 3, 6, 9, and 12 % w of fermentation medium. The culture had been agitated by magnetic stirrer for 28 days before freeze drying method was conducted to obtain dry BC/PVA nanocomposite. The product of BC/PVA nanocomposite was then studied for thermal characteristics using Differential Scanning Calorimetry (DSC) and Thermogravimetry Analysis (TGA). Pure BC has melting temperature (Tm) at 350 . 3 o C and pure PVA at 181 . 3 o C. Experimental results showed that the higher PVA content in fermentation medium decreased the melting temperature of BC/PVA nanocomposite produced.
Effect of Catalyst Preparation Method on the Characteristics of Carbon Nanospheres as Anode Materials of Lithium Secondary Batteries
Authors: Arie Arenst Andreas , Kristianto Hans , Susanti Ratna Frida , Halim Martin , Lee Joong Kee
Published: August 2015

Carbon nanospheres (CNSs) were synthesized from commercial activated carbons and cooking oil as carbon precursors using simple pyrolytic process and then were used as anode materials of lithium secondary batteries Prior to the synthesis of CNSs, a series of Fe catalysts supported on commercial activated carbons were prepared by two different methods, namely impregnations and adsorptions. The effect of preparation method on the characteristics of CNSs were then studied by scanning electron microscopy (SEM) , transmission electron microscope (TEM) and BET surface area measurements. Preliminary electrochemical measurements of as-synthesized CNTs were carried out using cyclic voltammetry instruments at constant scan rate to see the mechanism of Li-ion insertion and extraction into/from CNSs structures during cycle tests.
Co-Sensitization Promoted Light Harvesting Capability of Dye-Sensitized Solar Cell (DSSC) Using Anthocyanin-Based Dye
Authors: Eka Putri Irana , Leonard Sidik M. , Wahyuono Ruri Agung , Sawitri Dyah , Risanti Doty Dewi
Published: August 2015

High efficiency of light-to-energy conversion in dye-sensitized solar cell (DSSC) was achieved by applying anthocyanin as photosensitizer and TiO2 as photoelectrode. TiO2 anatase phase was synthesized by using co-precipitation method from TiCl3 precipitate. Anthocyanin (A) from Garcinia mangostana pericarp was combined with β-carotene (B) from Daucus carota and curcumin (C) pigments from Curcuma longa. According to UV-Vis analysis the wavelength absorptions of anthocyanin, β-carotene, and curcumin are 399 nm, 471 nm, and 470 nm, respectively. The A–B–C produced the short-circuit current density (JSC) of 77.7 μA, the open-circuit voltage (VOC) of 343.2 mV, the fill factor (FF) of 32.3, and the efficiency (η) of 0.042%. It is found that there exists a synergistic effect between anthocyanin and curcumin as indicated by broader absorption wavelengths, whilst the mixture between anthocyanin and β-carotene does not show the synergistic effect. The high efficiency of layered co-sensitization is attributed to the high adsorption capacities of curcumin in the outer layer. On the other hand, the effect can be explained on the basis of light scattering effect.
Highly Oriented ZnO:Al Thin Films as an Alternative Transparent Conducting Oxide (TCO) for Windows Layer of Solar Cells
Authors: Marwoto Putut , Sugianto Sugianto , Sulhadi Sulhadi , Aryanto Didik , Wibowo Edy , Yanti Yanti
Published: August 2015

Aluminum doped zinc oxide (ZnO:Al) thin films were deposited on corning glass substrates using DC magnetron sputtering at various growth temperatures (27°C-400°C). X-rays diffraction spectroscopy (XRD) analysis showed the crystal structure of ZnO:Al thin films is wurtzite with c-axis orientation. By enhancing the growth temperature, the crystal size and the crystal stress are increase, while the resistivity of films decreases. Crystal size increase from 35 nm to 52 nm, the stress increase from -7.689 GPa to -5.126 GPa, while the resistivity decreases from 6.29 x 104 Ωcm to 4.05 x 103 Ωcm. Generally, the quality of crystal enhanced as the raising of growth temperature.
Physical and Chemical Modification of Sorghum Flour for the Potential Substitute of Wheat Flour
Authors: Susanto Heru , Fitrianingtyas M. , Rokhati N. , Hakiim A. , Sistihapsari F.
Published: August 2015

The huge amount of wheat import causes efforts to find substitutes for wheat flour are very important in Indonesia. In this work, sorghum (Sorghum bicolor (L)) flour was physically and chemically modified. The physical modification was performed by heat treatment and/or addition of a foodstuff having high protein content (soybean or green beans flour). Heat treatment was conducted by heating in an oven at temperature of 100°C, 110°C and 120°C for various times (14, 15, and 16 hours). The chemical modification was carried out by addition of acetic acid (5%, 10%, 15%, 20%, 25% v/v) followed by heating at temperature of 60°C, 70°C, and 80°C. The unmodified and modified sorghum flour were then characterized in term of swelling power and solubility. Overall, sorghum modification by physical and chemical treatment increases both swelling power and solubility. The physical modification shows that modified sorghum flour by heating (only) at 100°C for 15 hours has swelling power was 12.39% and percent of solubility was 2.3%, which is closer to wheat flour than other physical modifications. The chemical modification by addition of acetic acid 15% v/v followed by heating at temperature of 70°C resulted in modified sorghum with the swelling power of 12.31, which approaches the swelling power of wheat flour (12.84).
Use of Natural Silica Sand as a Component for Prospective Fuel Cell Sealing Materials
Authors: Musyarofah Musyarofah , Nurbaiti Upik , Dewa Egidius , Triwikantoro Triwikantoro , Mashuri Mashuri , Firdaus Sukma , Suminar Pratapa
Published: August 2015

A study to enhance the value of natural silica sand from Tanah Laut, South Kalimantan, Indonesia has been initiated. A number of local sands were selected as the candidates for the study. The selected sand contained more than 90% quartz and was further processed to obtain a high purity initial powder using magnetic separation and immersion with HCl. The sealing materials were prepared by mixing the natural-sand-based silica (SiO2) powder with magnesia (MgO) and boria (B2O3) with composition of 70:10:20 by weight followed by uniaxial pressing and finally sintering at 1150°C for 1h and 4 h to produce ceramic composites. XRD measurement revealed that the ceramic contained quartz, protoenstatite, and clinoenstatite. The 1h and 4h ceramics exhibited 1.89% and 0.43% apparent porosity, 7.00 106 and 6.63106 cm electrical resistivity, 3.60 and 2.29 GPa Vickers microhardness, and 11.2010-6 and 11.5510-6 ppm/°C thermal expansion coefficient respectively. The 4h sample is more appropriate for sealing function in fuel cell than the 1h sample.
Apparent Activation Energy in High Frequency Microwave Sintering of Alumina Ceramic
Authors: Sudiana Inyoman Nyoman , Mitsudo Seitaro , Inagaki Shunsuke , Ngkoimani La Ode , Rianse Usman , Aripin Haji
Published: August 2015

The observed enhancements in the high frequency microwave processing alumina compared to those in conventional method at the same sintering temperatures have been studied. Some possible mechanisms responsible for the enhancements were investigated and are discussed in this paper. The enhancements could be associated with the increase either in driving force or in apparent activation energy of diffusion. An experiment to estimate the driving force of sintering is not easy to perform because the force depends not only on the density and grain size but also on the electric field in the materials. Therefore, a series of experiments to estimate the apparent activation energy were performed in high frequencies microwave and in conventional sintering method, as well. It was observed that the apparent activation energy in conventional sintering was much lower than that of microwave sintering. These activation energy values suggested that diffusion rate in microwaves sintering was faster, which led to the higher densification.