bluuebunny/crossref_metadata_2025 huggingface dataset:
FEM-based Virtual Manufacturing and Testing Procedure for Resistance Spot Welding
Authors: Yusuf M. N. , Rahman W. E. W. , Manurung Y. H. P.
Published: June 2020

This research focused on the development of numerical approximation procedure applied for resistance spot welding process which includes testing procedure to evaluate the tensile strength of a spot welded joint. The spot weld is modelled according to standardized dimension for tensile test with main material properties of Cu-sw as electrode and low carbon steel S235 as sheets with 1mm thickness. It is including electric conductivity, resistivity and heat transfer coefficient in solid body as well as contact interface. The FEM simulation is conducted using the process parameter of current 15,000A, force 5,000 N and different stages of time following the welding process and tensile test which is simulated after released both electrodes and material reaches the initial temperature with contact clamp velocity of 5mm/min. It is expected that the resistance spot welding process can be successfully simulated and producing result within acceptable range of errors.
Steady-state heat flow through hollow clay bricks
Authors: Ghailane H , Ahamat M A , Padzi M Md , Beddu S
Published: June 2020

Clay bricks are commonly used for building wall. One of the functions of a wall is to create a habitable internal environment, such as enabling internal temperature to be controlled at a human comfort level (~24°C) which is lower than the outside temperature for hot and humid climate countries. Thus, it is important for clay bricks to minimize heat flow into the building to reduce the energy consumption by air-conditioning system. The aim of this paper is to investigate the reduction of heat flow through hollow clay bricks relative to solid bricks. Finite element method was used to simulate steady-state heat transfer through solid and hollow clay bricks. Several arrangements of cavities filled with air, wool and expanded foam were simulated. It was found that the effective thermal conductivity reached almost a constant when the void volume and reduction in cross-sectional area exceeds 10%. Generally, heat transfer through hollow clay brick is expected to be significantly lower than the solid clay brick. It can be concluded that building wall made from hollow clay bricks could reduce the energy consumption by its air conditioning system. Future work is on the transient heat flow analysis and evaluation of mechanical properties of hollow clay bricks.
Towards a smart simulation of surface modification by thermochemical treatments for stainless steel in the industrial revolution 4.0
Authors: Fanya Annissa , Haruman Esa , Adenan Mohd Shahriman
Published: June 2020

This paper provides a conceptual basis of the development of a virtual process control design using smart simulation in the thermochemical surface engineering design for stainless steel. A historical review as a foundation of further development in attaining a smart simulation on low temperature thermochemical treatments is highlighted. Both scientific platforms and commercial explorations are suggested to thoroughly study the possibility of attaining a smart simulation on this material manufacturing related field. It is concluded that three essential stages of future works need to be performed: the construction of base points, model and simulation development, and advancement of simulation related to additive manufacturing to create a smart simulation in the industry 4.0 era.
Capability analysis of Puck damage model in predicting the damage behavior of unidirectional composite laminates under different scenarios
Authors: Meon M S , Husain H , Saedon J B , Shawal S , Mohamad Nor N H , Rao M N , Schröder K-U
Published: June 2020

Composite materials have been broadly used in many engineering fields because of their distinctive properties. They have advantages over metals as their properties offer significant advantages such as very good strength to weight ratio. However, failure in composite structures due to interlaminar and intralaminar raises a maintenance concern because it can lead to invisible damage. Therefore, this paper presents the capability of three-dimensional Puck failure criteria with gradual degradation rule to predict the structural responses, as well as the onset and propagation of failure due to variation of the situation in a composite laminate. The proposed damage model is achieved via the implementation of user-subroutines both in statics and explicit analysis using Abaqus software. Three different scenarios are investigated which were open-hole tension, low-velocity impact, and multi-bolt double-lap joint. The force-displacement and force-time curves are recorded and compared with experimental data taken from literature to measure the performance of such damage model. It is found out that the model adopted here responses well with test curves and demonstrates the high capability of predicting the damage in the direction of in-plane and out-of-plane in a composite laminate.
Simulation of thermal spray process of a three phase flow calculation with substrate temperature of 300K
Authors: Noh M H M , Hamid A H A , Sawada N , Mori K
Published: June 2020

We propose a particle method (MPS method) which can analyse the large deformation, splitting and coalescence of liquid as a new calculation method and a gas-liquid coupling method of finite volume method which can stably solve the compressible flow. By doing this, we aim to solve the interface resolution problem in the interface capture method and to establish a complicated gas-liquid multiphase flow analysis method that can deal with large deformation case. At the temperature of 300K, the validity of the flow field is consistent with the reference. The processes from the acceleration and deformation of a droplet to the solidification of the droplet on a substrate are successfully being observed. The shape of the splat is influence by substrate temperature.
Comparative analysis on integrated digital forensic tools for digital forensic investigation
Authors: Lee Jae-Ung , Soh Woo-Young
Published: June 2020

As a variety of digital devices have recently become widely commercialized, digital forensics, a process where electronic information stored in digital devices is accurately identified, collected, preserved and analysed and the information is submitted to the court as evidence, is gaining enormous popularity. This paper analyses characteristics, applications, limitations of digital forensic tools and compare the tool with others in terms of ease of use, thereby helping investigators to adopt integrated digital forensic tools in their investigation.
Electromyography Analysis of Lower Extremity Muscles during Squat and Stoop Movement
Authors: Mohd Salleh Noor Azlina , Noor Sazali Muhammad Syukran Al-Baria , Che Zakaria Noor Ayuni , Mustafah Nadia Mohd , Azaman Aizreena
Published: June 2020

There are different styles of lifting objects of the ground, and each style gives out different percentage of contribution of each muscle. The purpose of this study is to investigate the muscle activity between stooping and squatting to avoid low back pain and how the muscle activities differ from a correct technique of squatting, and an incorrect one. The Rectus Abdominis, Erector Spinae, Quadriceps and Hamstrings muscle were chosen to be monitored for differences in this study. Selected subjects were two healthy males, with the same height and age, one subject has no experience in doing squats – define as amateur, and the other subject know the basic method of squat-ting – define as non-amateur. In order to capture and analyze the activity of the muscles, Myon EMG and ProEMG software were used. Participants performed, stooping and squatting movement for 12 repetitions with 5 minutes’ rest in between. The muscle activation strength was obtained by calculating the Root Mean Square of the EMG data. Results shows that the non-amateur gave out greater RMS difference in muscle activation for the Erector Spinae and Rectus Abdominis among other muscles compared to amateur for both stooping and squatting. Another finding was that, the results of a non-amateur were more balanced between both left and right muscles activation compared to the amateur subject. These observations raised the need of mind muscle connection and muscle coordination in order to lift efficiently in order to avoid low back injury.
Numerical computation for prediction of grain growth on stainless steel 316L
Authors: Muhammad Norasiah , Manurung Yupiter HP , Mat Muhd Faiz , Abdul Ghani Mohamad Syakir , Graf Marcel , Adams Tom-Eric , Kassim Khairulnizam , Adenan Shahriman
Published: June 2020

This research aims to predict the grain size growth using numerical computation. The material to be investigated is stainless steel 316L (SS316L). The mathematical modeling is derived into two cases, namely with the absence of precipitate (free growth) and with the presence of growing precipitates. The numerical computation involves ordinary differential equation using Runge-Kutta 4th order written with FORTRAN language. The experimental verification is carried out by using quenching and deformation dilatometers. It can be concluded that modified kinetic constant (Mo*) should be defined differently for certain temperature range.
MXene-graphene hybrid nanoflakes as friction modifiers for outboard engine oil
Authors: Rasheed Abdul Khaliq , Khalid Mohammad , Mohd Nor Ariff Farhan Bin , Wong Wai Yin , Duolikun Tuerxun , Natu Varun , Barsoum Michel. W. , Leo Bey Fen , Zaharin Haizum Aimi , Ghazali Mariyam Jameelah
Published: June 2020

MXenes are a relatively new type of two-dimensional materials which remain largely unexplored in terms of tribological applications. In this research, hybrid comprising Ti3C2-NG (MXene-Nitrogen-doped Graphene) is synthesized in an attempt to enhance the thermal and tribological properties of Outboard Marine Engine Oil. Oil sample were prepared using the two-step method which involved optimization of mixing technique and followed by tests according to ASTM standards. Results revealed that the thermal conductivity of the oil is enhanced by 6.62% for 15 minutes high shear blending whereas the viscosity is reduced by 4.71%. The decrease in viscosity could be as a result of pockets of debilitated intermolecular bonds in oil due to nanoparticles addition. Further, the Newtonian behaviour oil remains unchanged with the addition of nanoparticles. However, increasing shear rate revealed dilatant behaviour of the nanofluids corresponding to Taylor-Couette flow. The hybrid nanoflakes doesn’t significantly alter the anti-friction and anti-wear behaviour of the oils although the coefficient of friction is decreased in the presence of 0.01 wt.% Ti3C2 additive nanoparticle by a marginal <1%.
Development of Kuala Lumpur driving cycle for the estimation of fuel consumption and vehicular emission
Authors: Mohd Suhaimi Muhammad Farhan , Mohd Salleh Noor Azlina , Madani Sahari Dato’ Ts. Mohamad , Sarip Mohd Sharulnizam
Published: June 2020

Driving cycles is a series of data points representing the speed of vehicle verses time sequence profile developed for certain road, route, specific area or city. Generally, driving cycle is used to estimate the fuel consumption (FC) and vehicular exhaust emission. The common factors that affected the FC and exhaust emission are the engine operating conditions such as cold start, low engine loads and high engine loads which are found during actual driving. The research presents the measurement and analysis of engine conditions based on actual driving behaviours in an attempt to formulate representative driving cycle for Kuala Lumpur. The methodology used for this research is adapted from the Worldwide Harmonized Light-duty Test Cycle (WLTC) introduced by the working party on pollution and energy (GRPE) under the United Nations Economic Commission for Europe (UNECE). This research covered a wide area of paved road in Kuala Lumpur, about 62.34% by surveying the road condition on the eight selected routes. The used of On-board Diagnostic (OBD) and Global Positioning System (GPS) equipment are used to record the vehicle travel speed during data collection activity. The driving characteristics are then analysed from speed profile and its target statistic parameters are defined to develop representative driving cycle. The characteristics of the newly developed driving cycle are compared to the European driving cycle which is currently being used in Malaysia for new vehicle certification and registration. Therefore, the correlation of FC is derived to indicate the impacts of real-world driving conditions relative to domestic conditions.
Low Head Micro Hydro Systems for Rural Electrification
Authors: Tamiri F M , Ismail M A , Muzammil W K
Published: June 2020

Off-grid micro hydro is an economical and practical approach to generate electric power to fulfil energy demand in rural areas. Large numbers of successful high head micro hydro project have been reported however the application of low head micro hydro system is scarce. Low head micro hydro system commonly recognized using complex profile blades, larger civil structure and electromechanical components to extract energy. This leads to a more complex system and higher cost with respect to similar power rating. On the other hand, the potential to exploit low head micro hydro system is enormous because there is where population is concentrated. The aim of this paper is to present the main issues and technologies encircled the application of low head micro hydro power for rural electrifications. Reviews on relevant issues on micro hydro surrounding available turbines for low head sites, civil structures and electric motor are also presented. This is followed by accentuating the importance of information dissemination using the internet to potential users. The information can be used by researchers, plant managers, individual or rural communities to understand the potential of available technologies.
Electromyography (EMG) for Assessment in Low Back Pain; Erector Spinae Muscle
Authors: Che Hamid Nur Hajariah , Zakaria Ayuni Che , Mustafah Nadia Mohd , Azaman Aizreena , Johar Khairunnisa
Published: June 2020

The purpose of electromyography (EMG) study is to identify which position of surface EMG sensor attached to erector spinae muscle related with lower back pain by squat and stoop lifting technique. This is to avoid lower back pain (LBP) occur during Manual Materials Handling (MMH). There are only one types of upper extremity muscle were chosen to be monitored in this study which is erector spinae (ES) muscle with different electrodes placement on the surface electromyography (sEMG) sensor. However, each of the lifting styles come out with the different reading of root mean square (RMS) frequency for each muscle chosen. In this study, the two subjects consist of two females with normal body mass index (BMI) range from 18.5 to 24.9 with same physical measurement, was selected in order to perform both styles of lifting which are squatting and stooping. For every session the subject will undertake 15 repetitions with 15 minutes rest in between for each movement. In furtherance of to get the analysis muscle activity, proEMG software is used. The results of study for subject female 1 showed that the squat technique had higher levels of muscle activation compared to stoop technique on left erector spinae (LES) muscle. However, the LES muscle activation for subject 2 is greater at stoop activity. On the contrary, squat technique had lower fatigue analysis compared to stoop technique for both subjects on LES muscle. Conclusion, squat technique is better than stoop technique but stoop lift is more natural and spontaneously used for MMH.
Thermal Conductivity and Permeability Studies of Recycle Copper Wire Mesh
Authors: Michael Z. , Martius M. S. , Khairulmaini M. , Ismail M. H. , Halmy M. N. , Jahi T. M.
Published: June 2020

Copper is well known as a valuable material, particularly for electrical industries due to its excellent properties. Besides, the price for copper scrap is also higher in comparison with other metal scrap materials found in many electrical appliances such as computer equipment, electric motor, transformer, and other components. This paper describes the potential of recycled copper wire shaped into a form suitable for heat sink application. The samples of wire mesh for this research were fabricated by compacting copper wire with different weight. Compaction was done to form a cylindrical shape with a diameter and height of approximately 25 mm and 30 mm, respectively. These samples were evaluated for porosity, thermal conductivity, and permeability. The experimental results showed that the sample with the lowest porosity exhibited great promising conductivity. In addition, lowering the amount of copper wire in compaction resulted in low density, thus improved its lightweight properties. The greater amount of porosity resulted in greater permeability. The optimum properties with a combination of the excellent thermal conductivity and permeability are necessary for heat sink application to ensure that the parts work effectively.
The Effects of Hydrostatic Pressure on Corrosion of Coated Stainless Steel
Authors: Ahmad Nurulnatisya , Abdullah Bulan , Mohd Najib Adib Ruzaini , Alias Siti Khadijah , Sulaiman Syidatul Akma , Wong Freddawati Rashiddy
Published: June 2020

Underwater steel structure such as Remote Operated Vehicle (ROV) unit was exposed to corrosion element during its operated working hours and at different depth of sea level depending on its operational requirement. The different depth of each operational indicates the different pressure effects under water. The coated material was affected by the corrosion and may have changed in its micro substructure thus decreases the corrosion resistance. The aim of this study was to analyse the corrosion rate of the pressure effects on the coated materials through several testing. The type of coated material used is Commercial Anti-Corrosion spray. The tests done by pressurized the specimen at 2, 6 and 10 atm. The corrosion rates are determined by using immersion and weight loss. The specimens were soaked in the sea water with timeline of 24 hours. Scanning Electron Microscope (SEM) and microstructure observation are used to observed and determine the corrosion morphology of the specimen changes before and after immersion test. As a result, the pressure plays a major role on the corrosion effect and coating materials. The increments of pressure will deteriorated the corrosion resistance of the specimens. However, the coating materials can only slow down the deterioration process of the specimen.
Effect of surface attrition on hardness on the hardness and wear properties of 304 stainless steels
Authors: Alias S K , Halmy M N , Shah M A M , Ahmad N N , Sulaiman S A , Pahroraji H.F. , Abdullah B
Published: June 2020

The occurrence of wear in austenitic stainless steel is inevitably unavoidable due to the presence of high chromium content and other alloying elements that hinder the implementation of surface treatment process. This process is usually use to improve the hardness and wear properties of steels and alloys by diffusing hard protected layer on the surface of the material. This paper investigates the effect of surface attrition on the hardness and wear properties of paste boronized 304 stainless steel. Surface attrition treatment was applied onto the surface of 304 stainless steel before paste boronizing was conducted at temperature of 850°C for 8 hours holding times. The microstructure of the boronized samples before and after surface attrition treatment was then observed and recorded in order to compare the phase constituent and boride layer thickness. The hardness of each phases was then evaluated using Vickers microhardness test and the wear resistance test of both paste boronized sample and surface attrited samples after boronizing was performed using pin on disk test. The microstructure results show that there are presences of both FeB and Fe2B phases on the surface of Pa-B850 and Pa-SB with boride layer thickness improvement of 3 times compared to untreated samples. This lead to enhancement of both hardness and wear resistance of the paste boronized samples due to better protection on the surface of the 304 stainless steel. The improvement of wear and hardness properties of 304 stainless steel could introduce new application that could be exposed to environment containing friction and wear.
Numerical-experimental approach to assess the deflection behaviour of carbon fibre fishing rod
Authors: Sabrin Manssor Nur Aini , Ismail A M M , Zainal Abidin Nurrul Amilin , Aziz Mohd Azran , Mahmud Jamaluddin
Published: June 2020

Deflection of a commercial hollow type fishing rod is investigated in this research. The fishing rod of interest is of Abu Garcia brand, made of carbon fibre. Analytical, experimental and numerical approach were performed to assess the bending of the rod under maximum 1.25 kg load located at the tip which represents the rod in pulling. The deflection is defined by longitudinal displacement of each point of guide rings located along the fishing rod. A mathematical model based on basic bending theory of cantilevered beam is formulated to obtain the deflection and then experiment was carried out by immobilizing one end horizontally on the wall and applying at tip force. The final position of the rings was marked, and the displacements were recorded. Finite element model was developed as an isotropic and elastic material via ANSYS software. Results from all approach were compared and it was found that analytical and numerical able to predict a similar trend of bending behaviour. However, large discrepancies were observed in the experimental curves due to several reasons.
Effect of Different Preheating’s Temperature towards the Integrity of Weldment AISI 1045
Authors: Mat Shah M. A. , Rosli F. H. , Abdullah B. , Alias S. K. , Hamami G. , Halmy M. N.
Published: June 2020

The purpose of this paper is to show the effect of different preheating’s temperature for different thickness of AISI 1045 before it was welded by using Shield Metal Arc Welding (SMAW). The temperature of preheating approach that will be use are 200oC, 250oC and 300oC and were applied to pair of base plate metal with different thickness of 16mm, 22mm and 28mm. Then the pair samples had been welded by using Shield Metal Arc Welding (SMAW). To monitoring the temperature, non-contact type instrument which is thermomapping was used in this study. Time was recorded after preheating was applied and then was stopped when the desired temperature has been obtained. As to evaluate the weld quality, the macrostructure observation, dye penetration, hardness, and tensile test were conducted. As the result, it found that the electrode rod with size16mm and 22mm required preheating’s temperature around 200° C while for 28mm required temperature up to 250°C. This paper will give a deeper understanding about the effect of preheating in term of strength of joining. The result obtained from this study can be used to assist welder while performing welding on medium carbon steel.
Study on Hardness and Shear Strength with Microstructure Properties of Sn52Bi/Cu + 1% Al2O3 Nanoparticles
Authors: Singh Amares , Durairaj Rajkumar
Published: June 2020

The Sn-58Bi (SB) lead-free solder was added with 1% nanoparticles (NP) of aluminium oxide (Al2O3) to investigate the shear strength based on microstructure and joint properties. The microstructures of the SB added with 1% Al2O3 NP containing Bi precipitation and β-Sn grains. The spacing between the lamellar structures of a SB solder alloy was narrower. Proper arrangement of the microstructure of β-Sn, Bi and with the presence of Al2O3 as discrete particles (dispersion strengthening) contributes to the increase on the shear strength and hardness value. The shear strength of the SB added with 1% Al2O3 NP solder joint was enhanced by 50% compared to the bare SB solder joint while there was a 33% increase in the microhardness as well. The shear test was conducted based on ASTM D1002 specification of single lap joint method. The presence of Al2O3 NP along the interface (Hall-Petch effect) contributes to the improvement in the shear strength by reducing the thickness of the IMC layer and retarding the growth of the Cu6Sn5 IMC layer. This study provides evident results for the enhancement of the mechanical properties of the 1% Al2O3 NP added SB solder.
Ergonomic Interventions in Lighting Products Manufacturing Plant
Authors: Masahuling Amir Mazli , Saman Alias Mohd
Published: June 2020

This study emphasizes on ergonomic interventions at an assembly line in lighting products manufacturing plant located at Shah Alam, Selangor. Subjective assessment and direct observation methods were used to the operators and the workplace at manufacturing plant to uncover the problems. Subjective assessment used included interview and questionnaire via modified Nordic Musculoskeletal Questionnaires (NMQs). Direct observation involved site observations throughout the manufacturing plant completed with Rapid Upper Limb Assessment (RULA). The problems found that workers handled heavy lamps between the work station and poor design of lamp burning test station. Two ergonomics interventions were implemented. Wheel tray was applied for transporting the lamps in the assembly line, and new burning test station was introduced on the table. The implemented designs were simple and cost-effective. The ergonomics intervention was analysed and shown reduced in industrial risks and improved the working condition and occupational safety and health.
Exploring Colour Change Properties in 3D Print Photochromic PLA: towards Designing Central Cyanosis Actuator in a Baby Manikin
Authors: Fatihah Azmi Nur , Delbressine Frank , Feijs Loe , Peter Andriessen M.D.
Published: June 2020

A high fidelity baby manikin with a colour changing mechanism is required for medical training, especially for cyanosis skin colouration assessment in a newborn baby. However, commercially available baby manikin simulators do not have the real colour-change of cyanosis skin. The efforts in increasing the fidelity of the manikin might improve the accuracy of cyanosis evaluation among the novices, thus enhances the quality of the medical training. This study contributes towards designing a colour change actuator for central cyanosis simulation in a baby manikin for medical training. The actuation method of the 3D print photochromic PLA using a low-voltage UV LED and the evaluation of its colour properties using a colour measurement device are described. The colorimetric properties of the photochromic PLA were evaluated in CIE υ′ν′ colour space. Results are presented, showing a strong relationship between the colour intensity of the UV LED and the colour of the photochromic PLA. We reflect on the potential of the photochromic PLA as an actuator in imitating the cyanosis in a baby manikin. The specific PLA we used still cannot simulate the cyanosis well. However, the idea of using PLA photochromic is still considered promising.
Synthesis and Tribological Characterization of Copper Based Composites Containing Carbide
Authors: Tyagi Rajnesh , Singh Gautam Rohit Kumar
Published: June 2020

Keeping in view the importance of the Cu based composites in sliding electric contact applications, the aim of the study is synthesise copper-chromium alloy based composites containing different wt. % of TiC by using a cost effective stir casting technique and to compare their mechanical and tribological behaviour. The study also proposes to analyse the friction and wear behaviour of the formed composites under the sliding speed of 1m/s and load varied 5 N, 10 N, 15 N and 20 N. The hardness of the composite Cu-1wt%Cr-1wt%TiC and Cu-1wt%Cr-2wt%TiC has been found to increase slightly when compared with Cu-Cr alloy and as received Cu. The wear rate was found to show linear trend with increasing normal load following the Archard law. However, composites were found to show low wear as compared to that observed in pure copper. This might be due to high hardness of the composite, the compact transfer layer of wear debris and due to presence of hard TiC particles whicg results in a lower real area of contact which further causes lower wear. There was found no cracks in the composite. The addition of chromium was found to increase the wettability and mechanical properties. The composite hardness and strength was found to increase with addition of TiC and chromium element in the matrix phase up to certain content.
Simulating tribological characteristics of Palm Methyl Ester (PME) lubricated contact
Authors: Hamdan S H , Chong W W F
Published: June 2020

The study simulates the lubricant Stribeck curve for Palm Methyl Ester (PME) by coupling modified Reynolds solution with Greenwood and Tripp’s rough surface contact model. The predicted lubricant Stribeck curves for PME is validated with measured data from a pin-on-disc tribometer. The Reynolds equation is modified to accommodate for the lubricant properties of PME (e.g. viscosity and density), which is mathematically described using Gibbs energy additivity approach. Solving the modified Reynolds equation would then provide the fluid film formation behaviour of PME, such as the contact pressure and film thickness. These fluid film parameters are then used as the input to determine the boundary and viscous friction of the investigated lubricated contact using Greenwood and Tripp’s rough surface contact model. The proposed mathematical solution correlates well with experimental data and is shown to be capable of predicting lubricant Stribeck, capturing the frictional behavior for the whole range of lubrication regimes. The findings of the present study prepare for a mathematical foundation to further explore the use of biodiesel as an alternative biodegradable lubricant to mineral-based ones.
FEM Simulation Procedure for Distortion and Residual Stress Analysis of Wire Arc Additive Manufacturing
Authors: Ahmad Siti Nursyahirah , Manurung Yupiter HP , Mat Muhd Faiz , Minggu Zaidi , Jaffar Ahmed , Pruller Simon , Leitner Martin
Published: June 2020

This fundamental research presents an investigation of Wire Arc Additive Manufacturing (WAAM) process on distortion and residual stress using numerical simulation. Further, WAAM geometry was modeled using simplified rectangular bead shape with five layers and three strings. The thermo-mechanical numerical simulation is conducted under consideration of non-linear isotropic hardening modeled by using general purposed FEM software MSC Marc/Mentat. In this simulation, different heat source models (Goldak’s double-ellipsoid and rectangular) are implemented and compared, whereby the later model was to be developed by using subroutine provided in the software. For analyzing the residual stress, separation technique between wall and substrate was introduced after the cooling down period. The outcome of this research is to develop an effective procedure to analyze the distortion and residual stress of wire arc additive manufacturing of stainless steel.
Tool wear analysis of ceramic cutting tools in the turning of gray cast iron materials
Authors: Lubis S , Darmawan S , Rosehan  , Winata W , Zulkarnain M
Published: June 2020

The development of mechanical and physical properties of metal materials is so fast, that it requires cutting tools that are capable of cutting the metal.Cutting tools must have high temperature resistance, high wear and hardness. Ceramic cutting tools have these properties, so they are suitable for use in cutting hard metals. In the metal machining process, especially machining of cast iron which has high hardness and strength, has a strong reason to use the ceramic cutting tool.This research was conducted to determine wear on ceramic cutting tools when cutting cast iron.The study was carried out experimentally using a Mazak CNC lathe.When the turning process is done, the cutting tool cuts the metal cast iron. Every 10 minutes, the turning process is stopped to observe and measure the wear that occurs on the ceramic cutting tool. Observations and measurements are carried out using a digital microscope.The wear criteria are determined if the tool edge (VB) has been worn at 0.3 mm.The results showed that wear at the cutting speed of 200 m / min at 60 minutes is an adhesion process. BUE (Build Up Edge) wear is a buildup of material layers in the chip area near the cutting tool.
Development and characterization of porous hydroxyapatite-Alumina composite for engineering application
Authors: Arifin A , Gunawan  , Priyadi A , Sanjaya F A
Published: June 2020

Synthetic hydroxyapatite is a material that has a chemical composition and molecular structure similar to bones and teeth, generally this material is widely used for medical applications including as an implant material. Non-medical applications of porous HA include as catalyst in chemical reaction, packing media for column chromatography, and as probe for gas sensors. The study aims to develop porous material based HA/Al2O3 composites. HA/Al2O3 composites prepared with three variations of latex space holder weight fractions namely 10%, 20%, and 30% and using the unidirectional compaction method to produce composites. Two step holding process sintering process applied on the green body specimens. Firstly, hold for 60 minutes at temperature of 600°C and secondly 3 hours at final temperature of 1200°C with 5°C/min heating rate. The apparent density test was performed based on the Archimedes’ principle. Porosity characteristics of the sample show that density of the composite decreased with increased space holder. Compressive strength results show that the addition of SH weight fraction decreased the compressive strength of porous hydroxyapatite-Al2O3 composites. The morphology observation via SEM showed pore formation due to burning of space holder and interconnecting porous formed.
Flower baggings in affecting mangosteen fruit qualities at harvest and during storage
Authors: Widodo S E , Kamal M , Zulferiyenni  , Chandra D , Kusuma D W
Published: June 2020

Physiological causes and insect attact are believed to increase yellow latex exudates in mangosteen fruits. To inhibit the causes, flower bagging should be applied. This research was aimed at studying the effects of flower baggings to two different flower developments in affecting mangosteen fruit qualities at harvest and during storage. Three bagging materials (unbagged, paper, and baloon) were applied to flowers of 2 and 4 weeks after anthesis (WAA). The fruits were sampled every 2 weeks during the periods of 8-16 WAA. The results showed that except α-mangosteen content that was slightly decreased during the latest periode of fruit growth by bagging at preharvest, flower baggings of both bagging materials and application periods mostly did not affect mangosteen fruit qualities at harvest, but they affected fruit shelf-life and qualities during storage. Flower baggings resulted in increased fruit shelf-life, with paper bagging applied in 2 WAA was better than that applied in 4 WAA. Paper bagging in 2 WAA resulted in the mangosteen fruit shelf-life of 29 days compared to 4 WAA which resulted in 14 days shelf-life. This research proved also that the occurence of yellow latex was much more likely affected by physiological causes, not by insect attacts.
The analysis of straw mushroom potential development using an empty fruit bunches materials
Authors: Sarono  , Sukaryana Yana , Arifin Zainal , Astuti Sri
Published: June 2020

The empty fruit bunches (EFB) known as a waste material from crude palm oil (CPO) production. It has widely studied for the potential used of EFB. One of products produced from EFB with development potentials is straw mushroom. The objective of this research was to analyze the potentials of EFB material and straw mushroom based on EFB material in Lampung province. The result showed that the EFB potential in Lampung province was 111,144 ton annually and straw mushroom was 4,835 ton annually. The biology efficiency ratio of EFB into straw mushroom in production scale was averagely 3.93%. Districts having potentials for developing straw mushroom business by using EFB material were Mesuji, Middle Lampung, Tulang Bawang, Way Kanan, and North Lampung.
Delignification of Abaca Fiber (Musa textilis) as Potential Substitute for Eucalyptus pellita
Authors: Darmawan A , Irawan B , Ni’mah H , Roesyadi A , Kurniawansyah F
Published: June 2020

Five years oldEucalyptus pellitais a raw material used to manufacture pulp in Indonesia. In the field, the cropping cycle of this wood is still considered too long, so the need to develop other alternative raw materials that have characteristics similar to the fiber planting a shorter cycle. One of the alternative raw materials is abaca fiber(Musa textilis).Abaca fiber is preferred over other fibers because of its good tensile strength and resistance to rotting. In the present work, delignification of abaca fiber was carried out by kraft pulping process and characterized in term of their mechanical properties. Abaca fibers were treated with kraft pulping and oxygen delignification. Eucalyptus kraft pulp was also characterized as a comparison. Kappa number and viscosity decreased when the active alkali charge increased. Kraft pulp abaca with high cooking results and good viscosity is easily delignified by converting oxygen to low kappa numbers (7-9) without significant loss in viscosity. In addition, from the final results, the kappa number and viscosity, it was shown that abaca pulp has very high strength. Although oxygen delignification for lower kappa quantities can be considered, in terms of the properties of the pulp the abaca fiber is suitable as a raw material for pulp.
Enhanced cloud based mobile core network with network function virtualization
Authors: Septama H D , Ulvan A , Pratama M
Published: June 2020

The mobile technology is improved by adopt the Internet Protocol (IP) based technology. The IP Multimedia Subsystem or IP Multimedia Core Network Subsystem (IMS) is a technology designed by 3rd Generation Partnership Project (3GPP). This technology used IP to deliver the communication packet and recognized as Next Generation Network (NGN). The emerging IP based technology took a lot of advantages by using IP to deliver a packet. However, some issues i.e. availability, security and reliability still need consideration to meet the telecommunication standard. The cloud based computing become buzzword as a technology for cost reduction and hardware efficiencies. This paper conducted the feasibility to setup mobile core network in cloud based environment and enhanced it with network function virtualization (NFV) feature. The NFV made the network more scalable, efficient and robust network management. The QoS is presented as the results to concluded the feasibilities. The results show that cloud based mobile core network with NFV is feasible since the QoS still full fill the telecommunication standard.
Effect of sintering holding time on the properties of Hydroxyapatite granules fabrication using dripping technique of HA-Alginate sintered at 1000 °C
Authors: Effendi M D , Gustiono D
Published: June 2020

CaP granules as bone graft are used for open defect of bone, where is not necessary mechanical stability they are proposed for no-load bearing applications. The important feature in the physical structure of a synthetic ceramic bone graft is its porosity, pore size, the volume of porosity and interconnections between the pores are three crucial parameters. The pore structure is of great importance for osteoconduction. The level of porosity, pore size distribution and degree of pore interconnectivity significantly influence the extent of bone ingrowth. According to that, this study investigated the effect of sintering holding time on properties of droplet synthetic ha-alginate using dripping technique sintered at 1000 0C with sintering holding time at 1: 2 :3 hours respectively. XRD was used to investigate of phases of the sintered droplet. Scanning Electron Microscope (SEM) was used to investigate the microstructure of beads. In this work, we can conclude that the holding time increased, the crystallinity increased but on the other hand, pore size, porosity, and surface roughness decreased. For all investigated samples. The surface roughness of A102 (0.2 – 2, μm) which is sintered at 1000 0C 2 hours holding time has a better value offered better cell colonialization and has no significant value of porosity (50%) and crystallinity (86.63%) than those of A103 which need more energy for sintering as a consequence.
Effect of porogen agent on microstructure of CaP granules using the gelation of alginate droplet formation
Authors: Effendi M D , Gustiono D , Lukmana
Published: June 2020

CaP granules are used for open defect of bone. The important feature in the physical structure of a synthetic ceramic is its porosity. Pore structure is great importance for osteoconduction. The main objective of this study is to investigate the effect of adding carbon black as porogen agent on microstructure of CaP granules of droplet CaP. According to that, certain carbon black (325 mesh) has added into composition of microspheres CaP-alginate gelation with ratio CaP:Carbon black was 0.5, 1, and 1,5 weight ratios respectively. Scanning Electron Microscope (SEM) was used to investigate microstructure of droplet and shown that Irregular shape grain. Internal microstructure appears more open for samples produced without a presence of alginate after sintering process and confirmed by XRD pattern for whole samples. The porosity and pore size increased by increasing CB. On the other hand, no significant change on surface roughness and no transformation phase caused by adding CB. So that, it can be concluded that CB can serve as a porogen agent.
Implementation of fuzzy-profile matching in determining drug suitability for hypertensive patients
Authors: Wantoro A , Syarif A , Muludi K , Nisa K
Published: June 2020

Treatments of patients with hypertension can be done in two ways, namely modifying lifestyle and antihypertensive drugs. Generally giving hypertensive drugs depends on age, history of illness, smoking habits, obesity and on diseases such as diabetes, kidney failure, heart failure and ischemic heart disease. Inappropriate use of antihypertensive drugs often causes complaints such as fever, diarrhea, diabetes, mouth breathing, nerve disorders, radiation to the neck and head area. In providing hypertensive drugs that are appropriate to the patient’s condition, doctor and medical personnels are required to have high pharmacological knowledge. Not all hospitals have pharmacology experts, therefore this study was conducted to develop a model that can be used as a drug suitability model based on the patient’s condition. The method used in this study is Weight Matching Using Fuzzy Logic. Based on the results of comparisons with expert 1 and expert 2, the results of the average system testing are obtained with a value of 100% precision, recall 96.6% and accuracy 96.5%. Tests show that the application with a fuzzy logic approach can increase the efficiency of 9.5% compared to the interpolation weighting method.
Surface plasmon dispersion and modes on the graphene metasurface with periodical ribbon arrays
Authors: Liu Yong-Qiang , Li Liangsheng , Yin Hongcheng
Published: June 2020

Graphene plasmonics on the structured metasurface demonstrate many exotic properties which can combine novel nanomaterials and well-established plasmonics, providing unique opportunities to develop a series of novel photonic, plasmonic and optoelectronic devices across a wideband spectrum. Dispersion theory and its propagating characteristics of surface plasmon polaritons (SSPs) mode along the graphene metasurface can provide a powerful guidance to design related devices and systems. In this paper, the fundamental dispersion theory and the numerical studies of graphene SSPs (GSPs) on a graphene metasurface i.e. periodical ribbon arrays which are bounded by a superstrate and substrate dielectric are presented. The dispersion expression of GSPs is deduced and revealed by a modal expansion method combined with periodical boundary conditions on the structure. According to this fully analytical dispersion expression of SSPs mode on the graphene metasurface, the dispersion characteristics, propagation loss and field profiles of SSPs mode with different graphene material parameters (e.g. graphene ribbon width and chemical potential) and bounded dielectric mediums are studied and analyzed in detail in terahertz (THz) band. Moreover, the dynamical tunable dispersion characteristics of SSPs mode on the graphene metasurface via electrostatic gating of a ground metal plate can be readily obtained by applying a graphene biased voltage model to this analytical dispersion theory. The presented studies on the dispersion theory of the graphene metasurface provide an analytical method to understand the propagation characteristics of SSPs mode on the structure. Besides, the calculation results on the structure can also be used to design some novel graphene-based optoelectronic and plasmonic devices with planar gradient-index distributions such as couplers, tunable focused lens and enhanced radiation sources in THz band.
Regime-Centered and Court-Centered Understandings: The Reception of American Constitutional Law in Contemporary China†
Authors: Liu Han
Published: June 2020

American constitutional law haunts the contemporary Chinese constitutional imagination. China’s reception of American constitutional law occurred in two major stages. In the first stage, which spanned from the 1980s to the early 1990s, Chinese intellectuals understood American constitutionalism as a particular political regime to be politically criticized or objectively appraised, with the tripartite separation of powers overwhelmingly highlighted as a core feature of the American constitutional-political system. In the second stage, which began in the late 1990s, a paradigmatic shift from a political, regime-centered perspective to a legalized, court-centered approach occurred in China’s introductions to and studies of American constitutionalism. The U.S. Supreme Court and the concept of judicial review now primarily preoccupy most Chinese constitutional minds; these features of the American system have formed the focal points of reference for Chinese constitutional reform. This shift from the first stage to the second reflects both ideological and social changes since the economic reform in China, as well as international impacts.
A Bayesian framework for inter-cellular information sharing improves dscRNA-seq quantification
Authors: Srivastava Avi , Malik Laraib , Sarkar Hirak , Patro Rob
Published: June 2020

Motivation

Droplet-based single-cell RNA-seq (dscRNA-seq) data are being generated at an unprecedented pace, and the accurate estimation of gene-level abundances for each cell is a crucial first step in most dscRNA-seq analyses. When pre-processing the raw dscRNA-seq data to generate a count matrix, care must be taken to account for the potentially large number of multi-mapping locations per read. The sparsity of dscRNA-seq data, and the strong 3’ sampling bias, makes it difficult to disambiguate cases where there is no uniquely mapping read to any of the candidate target genes.

Results

We introduce a Bayesian framework for information sharing across cells within a sample, or across multiple modalities of data using the same sample, to improve gene quantification estimates for dscRNA-seq data. We use an anchor-based approach to connect cells with similar gene-expression patterns, and learn informative, empirical priors which we provide to alevin’s gene multi-mapping resolution algorithm. This improves the quantification estimates for genes with no uniquely mapping reads (i.e. when there is no unique intra-cellular information). We show our new model improves the per cell gene-level estimates and provides a principled framework for information sharing across multiple modalities. We test our method on a combination of simulated and real datasets under various setups.

Availability and implementation

The information sharing model is included in alevin and is implemented in C++14. It is available as open-source software, under GPL v3, at https://github.com/COMBINE-lab/salmon as of version 1.1.0.