bluuebunny/crossref_metadata_2025 huggingface dataset:
Universal Rocket Space Engine and solving the problem of space debris
Authors: Glazkov V V , Sinkevich O A , Shmelkov G B
Published: November 2019

The total mass of only large fragments of space debris in low-earth orbits(LEO) exceeds 7,500 tons. The well-known concepts of solving the problem of space debris are considered. An approach to space debris as a valuable resource is formulated. It is proposed to use space debris as a propellant for the Universal Rocket Space Engine (URSE). The engine should consist of a thermal rocket engine in conjunction with accelerator – railgun, for example. The steam generated during the evaporation of space debris speeds accelerates to 10 – 50 km/s in this scheme. Power supply of the engine is planned to be implemented by solar energy or a nuclear power plant. When particles of debris passing through a high-temperature evaporator, it turns into steam. Then the steam passes into the nozzle, where the railgun is located. After railgun, the accelerating plasma expires in space. There are three methods to obtain high-temperature vapor in the evaporator: solar furnace (direct heating), electric arc heating or ion sputtering technology. The project is proposed to be divided into several stages, each characterized by the use of various technical solutions. URSE will allow using not only space debris, but also materials of small celestial bodies as fuel for space flights within the solar system. This will make it possible to radically change the schemes of space flight, since restrictions on the mass of fuel using the URSE are removed. For example, during flying from Mars to Earth, the material of the Martian satellites of Phobos and Deimos can be used as a propellant.
Optimization of thermophysical processes of bottom part of shaft furnace for plasma treatment plant of solid radioactive waste
Authors: Yu Markelov A , Kudrinskiy A A , Anpilov S V , Shiryaevsky V L
Published: November 2019

The task of analyzing various sources of heating in the bottom part of the shaft furnace to optimize thermophysical processes is of interest from both an economic and technological point of view. When replacing the type of heat source, it is necessary to preserve the performance characteristics, primarily high temperatures in the range of 1400-1600 °C for melting minerals. This work aims to substantiate plasma torches replacement by natural gas or diesel burners and to confirm preservation of the utilization process efficiency. In order to do this numerical modeling of thermal processes was used: CFD modeling of a full-sized shaft furnace with a melter, including the distribution of temperature fields in the slag melt layer and external thermal insulation materials. Other possible combinations were also analyzed to optimize heat exchange processes: ohmic heating of the melt, replacement of air with oxygen. The results of numerical simulation show that hydrocarbon burners can be used instead of plasma torches for efficient processing of various types of waste in the slag melt. This can be economically attractive for expanding the application area of waste treatment technology in the slag melt, especially for the housing sector waste processing.
Complex modeling of installation for thermal processing of organic compounds
Authors: Zroychikov N A , Fadeev S A , Kaverin A A
Published: November 2019

This paper presents the results of a numerical study of an installation for the thermal decomposition of organic substances by pyrolysis. Unlike with combustion, pyrolysis allows the processing of toxic and infected substances with high environmental safety. However, at the pre-project phase, difficulties often arise due to the lack of preliminary data relating to the decomposition process, the combustion of pyrolysis products, the intensity of heat exchange in the reactor and the combustion chamber. A possible solution to the problem may be pre-project computer simulation. In this paper, the ANSYS Fluent software program was used to simulate the installation of pyrolysis of moistened plastic, in which heat is supplied to the material through a heating wall. To maintain the process, the heat of combustion of its decomposition products is used. An approach of reducing the two-phase problem to a single-phase one is proposed, which allows minimizing the calculation time and increasing the convergence of the solution. Based on calculation results, the distribution of velocity fields, temperatures, heat fluxes and concentrations of substances in the installation was obtained. Calculation results allow to optimize the installation design and predict its capacity.
Tests of tungsten divertor mock-ups of tokamak-reactor with powerful plasma and e-beam loads
Authors: Budaev V P , Dedov A V , Komov A T , Fedorovich S D , Varava A N , Zakharenkov A V , Giniyatulin R N , Makhankov A N , Litunovsky N V , Frik P G , Van Oost G , Martynenko Yu V , Sliva A P , Lukashevsky M V , Karpov A V , Lazukin A V , Yu Marchenkov A , Gerasimov D N , Gubkin M K , Sviridov E V , Rogozin K A , Zakletsky Z A , Tupotilov I A , Gvozdevskaya D S , Ba Le Huang Chang
Published: November 2019

Plasma-facing materials of divertor and the first wall of a hybrid thermonuclear reactor are studied in plasma and beam facilities with extreme high thermal and beam load. Tests of tungsten divertor mock-ups of tokamak reactor are tested with high-heat flux in the plasma device and in the e-beam facility. Water-cooled mock-ups are tested with the combination of plasma and e-beam loads: (1) thermocyclic tests with electron beam powerful load from 5 to 10 MW/m2 and then (2) plasma tests in the PLM device with stationary plasma loads up to 1 MW/m2. These two tests are carried out for the first time and simulate the variable load on divertor plates in tokamak-reactor during stationary discharges with transient ELM events. The e-beam facility provides a complete simulation of the conditions of heating and cooling of the tested components. The advantages of the tests are stationary plasma discharges in the PLM plasma device modeling reactor conditions in the divertor and SOL.
Non-destructive chemical and phase layer profiling of multicomponent multilayer thin ultrathin films
Authors: Lubenchenko A V , Ivanov D A , Lubenchenko O I , Yachuk V A , Pavlov O N , Lashkov I A , Lukyantsev D S
Published: November 2019

This work covers a method of non-destructive layer profiling of ultra-thin films on solid. The method is based on solution of the problem of elastic and inelastic photoelectron scattering in multilayer inhomogeneous films. An example of depth profiling of an air-oxidized ultra-thin chromium film on a silicon substrate is given.
Study of High-Temperature Oxidation of the Claddings of Tolerant Fuel Elements of VVER-type Reactor
Authors: Polunin K K , Urusov A A , Bazyuk S S , Kiselev D S , Kuzma-Kichta Yu A
Published: November 2019

The work presents the results of a study of corrosion resistance of chrome-coated fragments of zirconium cladding of VVER-1000 reactor fuel elements. The coatings had been deposited by electrochemical deposition on the standard cladding fragments with pre-treated surfaces. Gas-dynamic treatment of the surface with chrome powder proved to have a positive effect on the surface-to-cladding adhesion. Annealing at a temperature of 400 °C contributes to relieving of the residual stresses resulting from the gas-dynamic treatment. Investigation of the durability of the coatings was performed under exposure to overheated steam at a temperature of 1200 °C and exposure period of up to 1500 s. As it has been demonstrated, the produced coatings hinder formation of ZrO2 oxide layer at the outer surface and reduce the depth of penetration of oxygen into the metallic sublayer, in comparison with the specimens in the original condition. All this contributes to retention of the residual ductility of the tested specimens at the level of no less than 2%.
The problems of intelligence improving of power plants process control system
Authors: Arakelyan E K , Andriushin A V , Pashchenko F F , Mezin S V
Published: November 2019

Trends in the development of modern control systems of technological processes (ACS TP) on the basis of program and technical complexes (PTC) are aimed at creating a unified control system of the power unit in all modes of its operation, capable in addition to directly controlling the power unit, blocking operator errors, using intelligent control strategies. At the same time, improving the quality of technological processes based on new hardware and software and the achievements of the modern theory of automatic control occurs mainly at the level of power unit equipment and to a much lesser extent – at the level of the power plant. It is obvious that the level of intelligence of ACS TP should correspond to the technical level of promising high-efficiency power plants. Under these conditions, the problem of increasing the degree of intelligence of energy production management systems in power plants through the development and implementation of new innovative technologies, algorithms and systems for optimal control of the operation of equipment of power plants and power plants in general is extremely urgent. At the same time, a set of technical solutions and technologies should provide, in addition to high efficiency, such “sparing” modes of operation, which allow to reduce the rate of exhaustion of the resource characteristics of the equipment and thereby prolong its service life. This shows the necessity and expediency of developing intelligent high-performance control systems for the entire cycle of energy production in power plants, by expanding the functionality of the PTC in terms of optimal control of technological and production processes of the block and station levels.
Lithium divertor of KTM tokamak
Authors: Lyublinski I E , Vertkov A V , Yu Zharkov M , Berlov A V , Tazhibayeva I L , Ponkratov Yu V , Gordienko Yu N , Zakharenkov A V
Published: November 2019

At present time the project of Kazakh material science tokamak KTM is under implementation. In addition to solving problems in the study of materials for fusion technologies on tokamak is working out innovative design elements of the divertor. The design of the lithium divertor module based on lithium capillary-porous systems has been developed and successfully tested under real tokamak conditions. In this design, the solution to the problem of removal of heat flows of high density was implemented through the use of a liquid metal coolant based on the eutectic alloy Na-K. Requirements to improve the safety and compatibility of the design of the divertor with other in-vessel elements of the tokamak, cooled by water, and limiting the temperature of the lithium receiving surface at <600°C at heat flows of 10-20 MW/m2 led to the creation of a new design solution for the experimental module of the divertor and the use of a new coolant – gas dispersed water flow (gas-water spray). The article describes and justifies the design solutions of the new version of the module, the parameters of the coolant and the cooling system scheme. Experimental results on determination of heat transfer coefficient for coolant based on gas-water spray are considered
A Review of Frequency Selection and Antenna Arrangement System for Microwave Imaging in Early Breast Cancer Detection
Authors: Jumaat Hadi , Ali Mohd Tarmizi , Ping Kismet Hong , Faudzi Najwa Mohd , Miswadi Nurfarahin , Yon Hamizan
Published: November 2019

Microwave imaging technique is one of the developing techniques that having attention by researcher around the world in early breast cancer monitoring due it is non-ionizing and the potential for cost saving and simpler system as compared to the current imaging techniques. The frequency selection is crucial in this application due to no bandwidth proven best. However, the amount of antenna is said affected the image resolution. This paper is an attempt to review the frequency selection and the antenna arrangement system in the past decades works for future antenna development in early breast cancer detection.
Segmentation of Cortical and Cancellous Bone with Osteogenesis Imperfecta using Thresholding-based Method
Authors: Voon Tan Tze , Som Mohd Hanafi Mat , Yazid Haniza , Basaruddin Khairul Salleh , Sulaiman Abdul Razak
Published: November 2019

Osteogenesis Imperfecta (OI) is a genetic bone disorders that mainly affect the bones which commonly leads to the multiple fractures. The purpose of this study is to segment the cortical and cancellous bone of tibia affected with the OI from the CT images. This project consists of two sections, segmentation of the cortical and cancellous bone, and the evaluation of the image performance. Contrast adjustment was implemented to enhance the contrast of images. K-Means and multi-threshold were implemented to segment the cortical bone at the proximal, diaphysis, and distal tibia. Post-processing was applied to further refine the segmented images. All segmented images were then evaluated by using the ground truth images. From the results, the process with contrast adjustment and multi-threshold obtained the highest accuracy and Dice-coefficient of 99.91% and 81.42% respectively at the proximal region while 99.93% and 73.88% at the distal region. However, pathway that make use of K-Means performed best in diaphysis region. This method has obtained the highest accuracy and Dice-coefficient of 99.98% and 95.59% respectively.
Pearson’s Correlation Coefficient Analysis of non-invasive Jaundice Detection based on Colour Card Technique
Authors: Abu Bakar Asyraf Hakimi , Mohd Hassan Mohd Najmuddin , Zakaria Ammar , Abdul Halim Ahmad Ashraf
Published: November 2019

Jaundice is describes as yellow discoloration of the skin and other tissues of a newborn infant. It happens when the bilirubin pigment rises up to 5 mg/dL or 85 μmol/L due the organs just started to developed. 75% of newborns in Malaysia had jaundice in the first week of life. Conventional assessment method is not convenient since it unable to detect all type of human skin colours, caused traumatization and costly. This research work proposed jaundice detection system based on the colour card technique that represent all types of human skin colours. This research does not involve any subject due to parent’s cooperation and ethics limitation. The input data is represented by the colour card shades. It represents random bilirubin colour in patient’s body, all types of human skin colour, and standard reference bilirubin concentration colour. It acquires input data by capturing different type of colour card shades using OPT101 photodiode sensor and USB4000-XR1-ES spectrometer. The input data collected were verified through Anderson-Darling normality test and analysed using Pearson’s correlation coefficient to measure the strength of the association between the two variables for each input sample tested. Based on the correlation results, it shows high correlation value (r=0.997). Percentage error analysis is used to validate the experimental device and shows value of 9.90% which prove this technique is reliable. The significant contributions of this work is the improvement of the accuracy in detecting jaundice level for all type of human skin colours through this system.
Fabrication and Biomechanical Evaluation of Polyurethane Material for Synthetic Bone
Authors: Zulkefli Siti Adawiyah , Shaikhani Maryam Hanim , Nasution Ahmad Kafrawi , Wahab Asnida Abdul , Abdul Kadir Mohammed Rafiq , Ramlee Muhammad Hanif
Published: November 2019

Synthetic bone has become an important tool for education in the orthopaedics field and biomechanical research. The use of the conventional tool such as cadaver has become a challenge to the researcher and orthopaedic surgeon, as it was highly cost, ethical issues and storage. In addition, the available synthetic bones in the market were expensive and only in European size. This research was focusing on developing the synthetic bone using polyurethane material, evaluate the mechanical strength of the developed synthetic bone and characterize the morphological structure of the developed synthetic bone. The development of the synthetic bone was using Polyurethane (PU) as its material. Two type composition of PU was used for this research. The material mixed and poured into the mould that has been designed according to American Society Testing and Material (ASTM) standard which was ASTM-F1839. Then, composition 1 and composition 2 undergo mechanical testing and morphology analysis by using Instron and Scanning Electron Microscopy (SEM) respectively. The average Young’s Modulus of composition 1 and composition 2 were 208.6963 MPa and 384.6304 MPa respectively. In short, the developed synthetic bone has greater Young’s modulus compared to the synthetic bone that available in the market and which are 132.3254 MPa (Sawbone) and 68.1483 MPa (Synbone). The morphological analysis has shown the fabricated synthetic bone has compact structure compare to the one in the market that mimic the cancellous bone. In conclusion, composition 2 of PU have the highest Young’s modulus but from the morphological analysis it does not mimic the morphology of cancellous bone.
Finite Element Approach Using Electrical Tomography for Bioassay Application
Authors: Ropandi Wan Aizatul Nadihah Binti , Zulkiflli Nur Amira , Nawi Nina Diana , Abdullah Fatin Aliah Phang , Pusppanathan Jaysuman , Zakaria Zulkarnay
Published: November 2019

Single-cell imaging is a part bioassay application that is highly used in the studies of microbiology. This bioassay application is used in order to determine the cell activity, behaviour and reaction as well as electrical properties and characteristic. Most of this can be achieved by using mass spectrometry, impedance analyser and flow cytometry. Currently, there is an emerging trend of on-chip integrated device that allows bioassay application to be performed real time. However, in terms of cell monitoring, which allows us to view the cross section image of cell, there is much to be explored. As each cell is composed of different material with specific relative permittivity, Electrical Capacitance Tomography is chosen to determine the electrical properties and spatial distribution of cell. Therefore, the purpose of this research is to simulate Electrical Capacitance Tomography for yeast cell growth in order to determine the most suitable configuration needed for ECT system.
Voice Pathology Analysis using DT-CWPT and ReliefF Algorithm
Authors: Kassim Farah Nazlia Che , Vijean Vikneswaran , Muthusamy Hariharan , Abdullah Rokiah , Abdullah Zulkapli
Published: November 2019

Voice pathology analysis has been one of the useful tools in the diagnosis of the pathological voice. This method is non-invasive, inexpensive and reduces time required for analysis. This paper investigates the feature extraction based on the Dual-Tree Complex Wavelet Packet Transform (DT-CWPT) with entropies and energy measures tested with two classifiers, k-Nearest Neighbors (k-NN) and Support Vector Machine (SVM). Feature selection using ReliefF algorithm is applied to reduce redundancy features set and obtain the optimum features for classification. Massachusetts Eye and Ear Infirmary (MEEI) voice disorders database and Saarbruecken Voice Database (SVD) are used. This research was done on multiclass and by specific pathology. The experimental results automates the process of voice analysis hence produce promising results of the presence of diseases in vocal folds.
Image quality assessment (IQA) using high-frequency and image variance (HFIV) for colour image
Authors: Tan Li Chien , Yazid Haniza , Chong Yen Fook
Published: November 2019

Image quality is often lost during image acquisition, transmission, and compression. Therefore, image quality assessment (IQA) is crucial in image processing. Currently, image quality can be measured from the frequency domain features, but it only applicable to blurred grayscale images. Nevertheless, noise distortion is also a common problem in digital images, and colour also affects the perception of image quality. Therefore, this paper proposes an enhanced blur and noise specific colour image quality assessment that measures high-frequency components and image variance. The number of high-frequency components is related to the edge and noise. In order to distinguish the distortion of the image, the image variance estimation is included. Experiments on public databases have shown that this method outperforms PSNR and SSIM in terms of noise and blur distortion and has low processing time of 0.0941 s/img.
The Effect of Material Characteristic of Shoe Soles during Long Duration Running
Authors: Cheng Chan Siow , Tan J P , Qing Tan Yin
Published: November 2019

Long duration running has been associated with musculoskeletal injuries such as patellofemoral pain syndrome and knee osteoarthritis. This study was designed to investigate the effects of two different shoe insoles on kinematic and kinetic performance during long duration running. In total 15 subjects (7 males and 8 females) were recruited to perform 15 minutes continuous running on the treadmill in 3 different shoe insole conditions: (i) no insole; (ii) Ethyl Vinyl Acetate (EVA) insole and (iii) Polyurethane (PU) insole. The result revealed a significant increase in maximum vertical ground reaction force (VGRF) with the PU insole compare with the no insole and EVA insole conditions (p<0.05). There is no difference between conditions in kinematic variables: step length, stride length and cadence (p>0.05).
Encapsulation of C. odorata extracts for antimicrobial activity
Authors: Azmi Siti Nur Amylina , Mohamad Che Wan Sharifah Robiah , Kasim Khairul Farihan
Published: November 2019

The purpose of this study is to investigate the relationship between the methycellulose (MC) and ethylcellulose (EC) of encapsulated C. odorata extracts (methanol and ethanol) and their antimicrobial properties against E. coli and Staphylococcus aureus. The encapsulated of C. odorata extract was prepared by solvent displacement method through dialysis tube cellulose membrane and it was freeze-dried to obtain the suspension of encapsulated C. odorata extract. Then, antimicrobial properties of encapsulated C. odorata extracts was performed by broth dilution method on target bacteria. A few drops of hydrochloric acid (HCl) were added into growth media until pH 4 to mimic the acidic conditions in human stomach. The results showed the encapsulated methylcellulose of methanol extract (MC-M) inhibit both bacteria types.
Classification of Microorganism Species Based on Volatile Metabolite Contents Similarity
Authors: Abdullah Azian Azamimi , Aziz Amira Najihah Abdul , Kanaya Shigehiko , Ranjan Dash Satya
Published: November 2019

Microorganism species can become pathogenic and cause bacterial infection, result from the imbalance in microbial ecosystem between host and microbe. Microorganisms emit secondary metabolites, known as volatile metabolites or organic compounds (VOCs) for various functions such as intra- or inter-species interactions, defense and attraction. Currently, VOCs are widely used as a biomarker for human diseases. This research is aimed to identify the relationship between microorganism species and volatile metabolite compound from the collected species and VOCs emitted organism data by using unsupervised machine learning approaches such as hierarchical clustering and graph-clustering method. Supervised machine learning methods also been used to classify the microorganism pathogenicity such as support vector machine (SVM) and random forest (RF). These data are collected from KNApSAcK and mVOC database where it provides most of the microorganism species and metabolites contents. From the collected data, there are in total of 1088 VOCs emitted by 517 microorganism species. As a result, the application of machine learning methods enable us to identify the relationship of species with their emitted VOCs and classify the microorganism species into their own pathogenicity.
PCA-Polynomial-ELM Model Optimal for Detection of NS1 Adulterated Salivary SERS Spectra
Authors: Othman Nur Hainani , Yoot Lee Khuan , Mohd Radzol Afaf Rozan , Mansor Wahidah , Amanina Yusoff Nur
Published: November 2019

Of recent, there has been much interest in the application of Surface Enhance Raman Spectroscopy (SERS) analysis in the detection of diseases such as dengue. Early diagnosis of dengue affords early intervention, greater chance of cure and prevention of mild dengue progressing into life threatening stage. SERS produces, on the interaction of photons from laser beam with saliva samples, a spectral image of its composition here. In the case of dengue fever, Non–Structural Protein 1 (NS1), being its biomarker, is the biochemical fingerprint to be revealed by SERS. NS1 presents in body fluid such as blood and saliva of patients since day one of infection, that makes NS1 a favourite alternative to antibody types of biomarker. However, the concentration of NS1 in saliva is low, yielding a low intensity SERS spectrum. In addition, the spectrum is usually interfered with undesirable noisy features. Extreme Learning Machine (ELM) is a fast algorithm with its strength in data pattern generalization. It has been applied in pattern recognition and machine learning for classification and regression, with encouraging performance. Our work here intends to determine an optimal polynomial-ELM model in classifying SERS spectra of saliva samples adulterated with NS1, amongst the different models subject to three different termination criteria of Principal Component Analysis (PCA). Performance of ‘100%’ is attained for accuracy, sensitivity, specificity and precision, while ‘1’ for kappa, by combining the cumulative percent of total variance (CPV) termination criterion and polynomial-ELM model of power 2 and constant 0.5.
Detection of Pulmonary Nodule using Shape-Based Feature Descriptor and Neural Network
Authors: Jusoh Nurfarhana Hazwani , Yazid Haniza , Basah Shafriza Nisha , Abdul Rahim Saufiah
Published: November 2019

This research aims to detect the pulmonary nodule presented in lung Computed Tomography (CT) scan images. Generally, a Computer-Aided Diagnostic (CAD) system was designed and developed to aid the radiologists in medical imaging department to reduce the time and to obtain faster and better results for lung nodules diagnosis of a patient. Four major stages involve in this paper which are pre-processing, segmentation, features extraction and classification. The images that were utilized were acquired from LIDC-IDRI database that available publicly for CT scan lung images. Initially, the median filter was employed in pre-processing to filter and remove the noises, unwanted distortions and artifacts presented in the images during scanning process. For the second stage, the implementation of Otsu thresholding (thresholding-based method) and watershed algorithm (region-based method) were used to segment the nodules (Region of Interest (ROI)). Manual cropping method was implemented to segment the nodule for further process. The main contribution of this paper is the extraction of the features based on shape descriptor. 10 features were extracted from the segmented nodules. Finally, all extracted features from the segmented nodules were classified into nodule candidates and non-nodule candidates using Back Propagation Neural Network (BPNN). Based on the experiment, it can be observed that the proposed approach works well with CT scan images and segmented the interested nodules with the accuracy of 94%. This semi-automated approach is fast compared with the conventional approach used by the radiologists in current time being.
Design and Optimize Solid Microneedle using Genetic Algorithm
Authors: Zaharin Nurul Fatihah , Markom Marni Azira , Tan Erdy Sulino Mohd Muslim , Sabani Norhayati
Published: November 2019

Microneedle is an example of Transdermal drug delivery (TTD) device. It is known for eliminating pain and inconvenient intravenous injections. This study presents a work on design microneedle and optimize the designs using Genetic Algorithm (GA). At first, a few solid microneedles are designed with difference parameters, and the considered parameters involve are shape of the needle, materials, size of array, base of microneedle, height of microneedle and number of needles on the microneedle’s array base. The microneedle is designed to meet the output requirement which are the total deformation and equivalent stress. Pressure on the tip and size of microneedle base are set to be constant which are 3.18 MPa and 2500 μm × 2500 μm × 50 μm, respectively. Then, optimisation process is conducted on the designs using Genetic Algorithm. Based on the optimisation results, it showed that the optimum structure for the studied microneedles is canonical type, diameter and needle height are 500 μm and 500 μm, respectively, PVA material and involve with 3 number of needles. The results showed that GA is capable to achieve the output requirement and able to optimize the parameter of the microneedle structure.
Hardened Glass Particle and Carbon Black Using Resin for Potential Electromagnetic Shielding in Biomedical Electronic Equipments
Authors: Meng Cheng Ee , Abdul Majid Mohd Shukry , Bakar Shahriman Abu , Mohd Nasir Nashrul Fazli , Fhan Khor Shing , Yeow You Kok , Yee Lee Kim , Mohd Jamir Mohd Ridzuan , Hong Tan Wei , Ridha Shaharuddin Shahrir , Chong You Beh
Published: November 2019

This study aims to investigate the electromagnetic properties of a composite of hardened glass particle and carbon using resin in determining the absorbability of the composite for electromagnetic interference (EMI). The electromagnetic absorption measurement was conducted using T-R method (transmission-reflection) by measuring the dielectric constant, loss factor, real and imaginary part of permeability, reflection coefficient and transmission coefficient. The measurement is taken for X band frequency and Ku band frequency within the frequency range from 8.2GHz to 12.4GHz and 12.4GHz to 18GHz, respectively. Dielectric constant of sample decrease when frequency increases. The high dielectric constant of material implies that the material has high absorbability of field energy, resulting in high attenuation of the applied field.
Investigation on Green Properties of Magnesium Alloy AZ31 Feedstocks Molded via Metal Injection Molding Process
Authors: Zainon Nooraizedfiza , Omar Mohd Afian , Rosli Nur Liyana Mohd , Marzuki Marina
Published: November 2019

Powder loading is an important parameter because of its role in part shrinkage, dimensional stability, and final density. Thus, this research investigated the properties of the molded magnesium feedstocks in determining the best powder loading for producing magnesium part through metal injection molding process. In this research, the feedstocks with three magnesium alloy AZ31 powder loading of (63, 65, 67) vol%, was prepared comprising the binder component of paraffin wax, high density polyethylene, waste plastic, and stearic acid (PW/HDPE/WP/SA) with weight fraction 55/21/14/10, respectively. After injection molding, the density, diamensional accuracy, and strength of the green part was investigated. The findings reveal that 65 vol% of powder loading resulting to the best green properties.
The Optimization of the Hydroxyapatite (HA) Material Characteristics Produced From Corbiculacea (Etok) Shells
Authors: Roslan Mohd Riza , Nasir Nashrul Fazli Mohd , Khalid Mohd Farid Abdul , Mohammad Nur Farahiyah , Meng Cheng Ee , Hashim Nor Nabielah Nazihah , You Beh Chong , Majid Mohd Shukry Abd. , Amin Nasrul Amri Mohd
Published: November 2019

Hydroxyapatite commonly used in medical field for tissue disease, bone disease, drug delivery and also for non-medical field purpose such as wastewater treatment. Due to excellent biocompatibility and bioactive properties, hydroxyapatite (HA) which is a group of calcium phosphate (CaP) and similar to the natural bone composition has been broadly ventured in medical area. Synthesising the HA was done via precipitation method by implementing the Corbiculacea (Etok) shells as the resource of calcium precursors. Calcination of Corbiculacea (Etok) shells took place to convert calcium carbonate (CaCO3
) to calcium oxide (CaO). CaO were then reacted with water to form calcium hydroxide (Ca(OH)2) and later, reacted with phosphoric acid(H
3
PO
4). This experiment manipulated the CaP ratio to study the properties HA formed. CaP ratios used are 1.50, 1.67 and 2.00. The characterization were performed using Energy Dispersive X-Ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM) and Fourier Transformation Infrared (FTIR).
Analysis of Drought Potential in Sumba Island until 2040 Caused by Climate Change
Authors: Sipayung Sinta Berliana , Susanti Indah , Maryadi Edy , Nurlatifah Amalia , Siswanto Bambang , Nafayest Muhammad , Putri Fanny Aditya , Hermawan Eddy
Published: November 2019

Climate Change is one of the events that can change climate components due to global warming events. One of the changes in climate components can cause changes in rainfall in an area. While changes in rainfall conditions in an area can cause increased vulnerability of a region to potential of drought. In this research, the effects of climate change on the drought potential in Sumbawa Island region was investigated, where this region is one of the areas prone to drought in Indonesia. Climate projection until 2040 was carried out using the Conformal Cubic Atmospheric Model (CCAM) model with 14 km spatial resolution and monthly temporal resolution. While the drought index is calculated by the SPI (Standardize Precipitation Index) method where positive numbers tend to mean wet, lift between -1 to 1 is neutral, and increasingly negative numbers tend to mean dry. It is known that in 2040 January was known that there would be no drought on Sumbawa Island with values ranging from -1 to 2. While in August of 2040, the potential for drought disaster should be watched out. This is because in this month the drought index value ranges from -2.5 to - 2. The potential for drought itself is known to increase in August 5 years until 2040 when compared with 5-year data, 2025 and 2030 in August in the Bima region. Meanwhile, based on time series analysis, it is estimated that there will be some extreme dry conditions, in August 2022, 2024, 2028, 2030, and 2033. Knowing these extreme conditions, it is hoped that this will become the basis for regional planning systems, starting from planning infrastructure and social systems to climate change mitigation and adaptation.
Analytical Hierarchy Process (AHP) in selecting suitable Marine Protected Area (MPA) site in Pulo Breuh (Breuh Island), Indonesia
Authors: Syahputra F , Muslim A M , Talaat W I A W , Irsalinda N
Published: November 2019

Marine protected area (MPA) is one of marine management tools that effective in regulating human activities within certain area. Therefore, choosing the location for the MPA is a critical step due to the nature of this tool that is prone to cause conflict and has broad impact to local and larger community. The selection processes require many criteria to consider thus this research use Analytical Hierarchy Process (AHP) method in Geographical Information System (GIS) to calculate MPA location. AHP has ability to simplify multidimensional criteria into single dimensional scale and GIS make is easier to analyze wide area. The research is conducted in Pulo Breuh (Breuh Island) Aceh Besar district of Aceh province, Indonesia. There are 6 components to calculate in determining MPA location for this island, the Settlement; Tourist Attraction; River; Aquaculture site; Ferry port and Fishing port, and each of this criterion is depicted into single layer of map based on the distance. The MPA needs to be close to the settlement and tourist attraction to ensure the advantages as well as far enough from the river, aquaculture site and ports. in the weighing criteria the priorities are, from highest to lowest, the settlement, aquaculture site, river, ferry port, fishing port, and tourist attraction. The result will be 3 levels of color-coded overlay map ranges from suitable, less suitable and not suitable place for MPA.
The Effect of Water Surface Level in sensible heat material on Yield of Single Basin Solar Still: Experimental Study
Authors: Mugisidi Dan , Fajar Berkah , Utomo Tony , Syaiful
Published: November 2019

The purpose of this experiment is to study the yield of the single basin solar still as an effect of water surface level in sensible heat material in a single basin solar still. The study is conducted on an open floor roof top at the Faculty of Engineering, Muhammadiyah University Prof. DR HAMKA in Jakarta, Indonesia. The study is conducted within two month and use 3 solar stills made of 3 mm Stainless Steel with dimensions 420 mm x 305 mm. The cover is made of 3 mm glass with a slope of 30 degrees. Iron sand that used as sensible heat material is taken from Glagah beach, Kulonprogo in Yogyakarta, Indonesia. 3 solar stills containing 20 mm height of iron sand. The height of the water in the three solar stills is 15mm (V1), 20mm (V2) and 25mm (V3) so that sequentially the surface of the water will be below the surface of the iron sand, the same as the surface of iron sand and above the surface of iron sand. The results obtained show that the daily yield accumulation of V2 is on average 49% higher than V1 while V3 is 57% higher above V1.
Comparative Study of p-type CuBi2O4 Films and CuBi2O4 Nanopillars Photocathode for High Performance Photoelectrochemical Water Splitting
Authors: Nasori Nasori , Rubiyanto Agus , Endarko Endarko
Published: November 2019

Traditional thin films and nanostructure are the most reasonable candidates to build the next generation of photoelectrochemical water splitting system with outstanding optical and electrical properties. Especially the use of nanostructure arrays as photoelectrodes might complement the traditional semiconductor photoelectrodes in providing close transfer distance of photoinduced carriers and the increase in the surface reaction sites than thin films. Both of the reasons reduce the probability of carriers recombination and thus enhancing the photoelectrochemical performances. In this work, we demonstrated highly efficient water splitting performance of CuBi2O4 nanopillars compared to thin film CuBi2O4 photocathode. The CuBi2O4 nanopillars were fabricated by electrodeposition on anodized aluminum oxide (AAO) template. The CuBi2O4 nanopillars photocathode gave a notable improvement in photocurrent, from −0.50 to −1.50 mA cm−2 at −0.45 V vs. Ag/AgCl by the external quantum yield more than 3 times at wavelength 420 nm. Finally, the result of the study appealed that the photoelectrode based on CuBi2O4 nanostructure arrays is an encouraging system for showing efficient water splitting system under visible light.
A Passive Cooling System for Increasing Efficiency of Solar Panel Output
Authors: Rakino Sunarno A. , Suherman S. , Hasan S. , Rambe A. H. , Gunawan
Published: November 2019

Solar cell converts solar energy to electrical energy. As its surface is continuously exposed to sun, solar cell efficiency decreases about 0.5% for 1°C surface temperature increment. Passive active cooling systems have been proposed by researchers. Since active cooling system absorbs the generated current, this paper considers passive system as the cheapest one. The combination of water and heat-sink cooling system is proposed. The experimental implementation shows that the proposed system is able to reduce solar panel surface temperature better than the only water or the only heat-sink cooling system. The output voltage increases in average 21.49% for average surface temperature decrement of 12.66% compared to basic solar panel. This results significant output power improvement, by more than 40%.
Earthquake Risk Reduction Study with Mapping an Active Fault at the Southern of East Java
Authors: Lestari Wien , Widodo Amien , Warnana Dwa Desa , Syaifuddin Firman
Published: November 2019

The southern part of Java Island is located between the two plates of the subduction zone, therefore this region had an active tectonic and volcanic activities. Those made a deformation of the geology around the southern part of Java island. This research was conducted to know the volume of deep geological structures to provide an overview of disaster warning systems in southern East Java region. The research that has been carried out using numerous active geophysical methods such as seismic methods had not been able to indicate internal structures. The needed for innovation used the integration of gravity and magnetotellurics methods. Bouguer anomaly gravity map became the supported data for interpretation. It showed low-density zones (0-80 mGal) between Pacitan-Trenggalek and beneath the Lumajang area which indicates the fault structure. Magnetotellurics (MT) which had a high penetration so that it is able to map deep active geological structures below the surface. The research area covered 8 regencies at the southern of East Java namely Pacitan, Trenggalek, Tulungagung, Blitar, Malang, Lumajang, Jember, and Banyuwangi. Magnetotelluric 1D processing showed indications of faults with orientations tend to be NE-SW between Pacitan and Trenggalek with depth (500 m – 8000 meter). Indications of faults with orientation tend to be NorthEast-SouthWest in Lumajang (100 - 500 meter).
Forecasting of Vannamei Shrimp Production Based on Weather Factors Using Radial Basis Function Neural Network Approach (Case Study: Lamongan District)
Authors: Albab M U , Irawan M I , Adzkiya D
Published: November 2019

One of the economic activity sectors that can be influenced by uncertain weather conditions is aquaculture production. In Lamongan, aquaculture production especially vannamei shrimp is very dependent on the ideal weather conditions. Uncertainty of the weather conditions can cause irregular harvesting to the production of vannamei shrimp. These trend changes can have an impact on the activities of production supply chain, namely the fulfillment of the entry quota of vannamei shrimp production from agents or distributors to exporters of vannamei shrimp to meet market demand. This marketing result can increase the original income of Lamongan area. To find out the development of the trend required a forecasting process and appropriate classification based on past data using artificial neural networks. One structure of artificial neural networks that can be predicting and classifying is a radial basis function neural network (RBFNN). The structure of RBFNN is trained using K-means clustering and gradient descent method. We use average temperature, average humidity and rainfall each month starting from January 2013 until December 2017 as the actual datasets. From those datasets, the training datasets start from January 2013 until December 2016 and the remaining datasets are used as the testing datasets. Built in the Python program, the test results show that our forecasting and classification had an accuracy level with mean absolute percentage error (MAPE) 16.7%.
Optimal Control Of Dynamic IS-LM Bussiness Cycle Model With Two Time Delay
Authors: Hidayati Airin Nur , Apriliani Erna , Usadha I Gst Ngr Rai
Published: November 2019

One of the business cycle model in the dynamics economy is the IS-LM business cycle model with time delay. This model talks about stability in the micro-economic system. Meanwhile, the time delay in the IS-LM business cycle model involve a change in stability at the equilibrium point so that a bifurcation is occurs. In this study, analysis of stability and optimal control on the IS-LM business cycle model with time delay. Based on simulation with numerical computation, show that there is a change in the stability when the delay value was given exceed the critical delay value. The stability change occur when the delay value arose a pure eigen value so that there was a limit cycle that show a Hopf bifurcation. Furthermore, optimal control in the IS-LM business cycle model given when the system changes to be unstable, i.e. when the delay value passed the critical delay value. Variable control use in the interest rate function. While the objective function maximize the total money supply from the country, the optimal solution is obtained by using the Pontryagin Maximum Principle. The results of this simulations with numerical computation show that maximizing the rate of income, the rate of interest rates, and the rate of capital stock lead to the stability point at thirtieth time.
An Application of Stochastic Dominance with Truncated Normal Disribution on LQ45 Index
Authors: Rahmawati Iga , Slamet Isnandar , Zukhronah Etik
Published: November 2019

Return is the profit obtained by investors from the capital invested in a company. The movement of stock prices in an exchange affect the condition of stock returns. Stochastic dominance with truncated normal distribution is an analysis method of stock dominance with parametric approach where the stock returns is bounded between two values. The purpose of this research is to obtain the optimum stocks listed in the LQ45 index using stochastic dominance with truncated normal distribution. The assumption of a truncated normal distribution is derived from the normal distribution of monthly stock returns that symmetrically truncated on two sides. The dominance of stocks then obtained by comparing the truncated cumulative distribution function of returns based on first order stochastic dominance (FSD) and second order stochastic dominance (SSD). Based on the analysis, it can be concluded that there are 17 stock combinations that dominated by FSD and 14 stock combinations that dominated by SSD.
Identification of Pekalongan Batik Images Using Backpropagation Method
Authors: Surya Rizky Andhika , Fadlil Abdul , Yudhana Anton
Published: November 2019

Batik is an Indonesian cultural heritage that was recognized by UNESCO in 2009. One of the famous batik producing regions in Indonesia is Pekalongan City, Central Java. Pekalongan Batik has a distinctive characteristic compared to other regions, namely from the aspect of color and motif. Pekalongan batik uses bright colors and flora motifs. However, there are some batik craftsmen who still use dark colors. Identify Pekalongan’s typical batik motifs become an obstacle for tourists that are visiting Indonesia. There needs to be an automatic identification system to recognize Pekalongan Batik motifs. The automatic identification system of batik images can contribute to the development of technology in the field of artificial intelligence. This research was conducted by collecting image data taken through observation, interviews and literature review. The image data obtained are four batik motifs. 5 images will be taken from each motif and will be implemented into the system using Matlab R2014a. The next process is feature extraction using the Gray Level Co-Occurrence Matrix (GLCM) method to get information in the batik image. The author then identifies image using the Backpropagation method to obtain the epoch value, learning rate, and accuracy value based on the identification process. The tested system obtained the highest accuracy of 91.2% with epoch 100 and learning rate 0.03 on Sogan batik, 89.6% accuracy with epoch 100 and learning rate 0.02 on Jlamprang batik. 87.2% accuracy was obtained from Cap Kombinasi batik and Tiga Negeri batik with epoch 100, the learning rate was 0.01 and 0.04 respectively. The results of identifying images of Pekalongan batik can be implemented in a more interactive application.