bluuebunny/crossref_metadata_2025 huggingface dataset:
72 Invitro embryo production using prepubertal calf oocytes with conventional semen and sexed semen ULTRA-4M
Authors: Velazquez A. , Alvarez H. , Kjelland M. , Villaseñor F. , Ariza G. , Romo S.
Published: December 2019

Invitro embryo production (IVP) can increase the reproductive potential and genetic quality of cattle, as well as other species. This powerful assisted reproduction tool can be used to produce embryos from prepubertal calves, reducing the generation interval. A recent sexed semen technology known as ULTRA (ST Genetics), completely modified the technique, the media and sperm concentration. In field trials with AI there was no difference between conventional semen (CONV) and ultra-sexed semen at a concentration of 4 million per straw (ULTRA-4M). The combined use of IVP and ULTRA-4M can decrease the selection time for improving dairy and beef cattle herd genetics. The objective of this research was to compare the CONV and ULTRA-4M semen using bovine IVP and prepubertal calves. The research was carried out in the reproduction laboratory of the Facultad de Estudios Superiores Cuautitlán - Universidad Nacional Autónoma de México (FESC-UNAM). The IVP was performed with a continuous invitro culture (IVC) system. The ovaries were collected in Campeche, México, from Bos indicus×Bos taurus crossbred calves (6 months old) using surgical castration (for export to the United States) and transported to the laboratory (FESC-UNAM) in BO-HEPES-IVM (Bioscience™), in an oocyte transporter (WTA). Vitrogen media were used for IVF and IVC. For IVM, the cumulus-oocyte complexes (COCs) were selected (only grades 1 and 2) and matured for 24h at 38.5°C. Matured oocytes (n=600, divided equally into five replicates) were divided into 2 groups, the CONV group and the ULTRA-4M group. The IVF process was conducted with CONV and ULTRA-4M semen from the same bull (Holstein) at a concentration of 2×106 and 0.5×106 spermatozoamL−1, respectively, for 18h in 38.5°C, 5% CO2, 95% air, and 100% humidity. The presumptive zygotes were denuded by pipetting and set in IVC until Day 7 at 38.5°C, 5% CO2, 5% O2, and 90% N2 at 100% humidity. The cleavage results were recorded 56h after the beginning of IVC. The cleavage rate, embryos with more than 6 cells, and blastocysts on Day 7 of culture were evaluated. The statistical analysis was carried out with the GLM procedure of the SAS software (version 9.3; SAS Institute Inc.) to evaluate the results of CONV vs. ULTRA-4M (α level=0.05). The percentage of cleavage for CONV was 46%±1.4 and 43.2%±1.4 for ULTRA-4M. The results for embryos with more than 6 cells in the CONV and ULTRA-4M groups were 16%±0.6 and 14%±0.6, respectively. The percentage of blastocysts on Day 7 for CONV was 9%±0.6 and 8%±0.6 for ULTRA-4M. There were no significant differences between groups (P>0.05) for all variables analysed. In conclusion, under the conditions of this research the ULTRA-4M and CONV produced similar results for IVP.
82 Stage-specific expression of lineage marker genes and pluripotency marker distribution in porcine pre-implantation embryos
Authors: Oh J. , Lee M. , Lee D. , Choi K. , Kim S. , Cho M. , Lee C.
Published: December 2019

Lineage specification in pre-implantation embryos has been revealed, and it was expedited recently by single cell studies. However, data on expression marker genes and proteins in porcine embryos were still missing. We aimed to investigate the expression and distribution of marker genes and proteins, respectively, in IVF and parthenogenetically activated (PA) embryos. For this, cumulus-free oocytes were co-incubated with sperm in modified Tris-buffered medium (mTBM) for 5h and PA was performed using an electric pulse in activation medium. Following this, the embryos were incubated in porcine zygote medium 3 (PZM3). We first tested gene expression level of lineage candidates (internal control; β-actin). In IVF embryos (30, 25, 20, 15, 10, and 5 embryos pooled on Day 2, 3, 4, 5, 6, and 7; replicated 3 times), trophectoderm (TE)-specific genes (Dab2, Gata3) showed peaks on Day 4-5. Within the 2 genes, Dab2 had an earlier peak than Gata3. Inner cell mass (ICM) marker candidates (Nanog, Sox2, and Hnf4a) had diverse patterns. The Nanog and Sox2 genes had peak expression on Day 3. The Nanog expression dropped gradually, but Sox2 dropped suddenly on Day 4. Otherwise, Hnf4a expressed little in Day 3 and expression was sustained from Day 4 to 7. Primitive endoderm markers showed the highest expression on Day 4. We also checked expression level of ICM markers (Sox2, Oct4, and Nanog) in PA embryos (20, 20, 20, 10, and 5 embryos were pooled in 2, 4, 6-8 cells, morula, early, and late blastocyst stages; replicated 3 times). Expression of markers was similar (the highest in the 6-8-cell stage; at least 7.3-, 4.5-, and 3.7-fold compared with the other stages in Sox2, Oct4, and Nanog). We used analysis of variance and Tukey's test for statistical analysis. Following this, we conducted immunocytochemistry with both IVF and PA embryos (20 in each condition). Primary antibodies were treated overnight at 4°C and appropriate secondary antibodies were treated 1h at room temperature. In the case of IVF, well-known ICM markers (SOX2, OCT4, NANOG, and SOX17) showed restricted distribution in nuclei of ICM cells. However, DAB2 was distributed in the cytoplasm of TE cells. In PA embryos, SOX2 and NANOG distributions were similar to IVF. The OCT4 in ICM cells from morula to early blastocyst was restricted, but not in Day 7 embryos. In conclusion, marker genes showed diverse expression pattern in IVF, but all ICM-specific genes had a similar pattern in PA. Also, ICM marker proteins were restricted in nuclei of ICM cells only except Day 7 PA. Our results provide eye-opening information on marker contribution to lineage specification of porcine embryos.
This work was supported by the National Research Foundation in Korea (NRF) funded by the Ministry of Education (NRF-2017R1D1A1B03032256, NRF-2019R1C1C1004514).
The effect of traditional bullying-victimization on behaviour cyberbullying among college students: Based on the structural equation mode / El efecto de la victimización por acoso tradicional en las conductas de ciberacoso entre estudiantes universitarios: un estudio basado en el modelo de ecuaciones estructurales
Authors: Dong Yinghong
Published: December 2019

The study aimed to establish an explanatory model for the effect of traditional bullying victimization on cyberbullying behaviour. The sample was composed of 354 college students (50% male and female) aged 17 to 24 ( M = 19.54, SD = 1.21) enrolled in three universities in Shandong province, China. They were investigated using the questionnaires of Bullied Scale, Moral Disengagement Scale, Perceived Anonymity Scale and Cyberbullying scale. Structural equation model was conducted to identify the effect of traditional bully-victimization on cyberbullying behaviour and the mediating role of moral disengagement, as well as the moderating role of perceived anonymity of cyberspace. In this sample, traditional bully victimization may lead the college students to engage in cyberbullying behaviour positively. Moral disengagement was the mediator between traditional bully victimization and cyberbullying behaviour. The perceived anonymity of cyberspace was the moderator between traditional bully victimization and cyberbullying behaviour. College students who were victims of traditional bullying showed a higher tendency of becoming cyberbullying assaulters via the partial influence of moral disengagement, and the effect was magnified by the perceived anonymity of cyberspace.
Development of portable solar storage device
Authors: Roslan M S , Adan F , Mohammad M A , Norazman N , Haizam S , Haider Z
Published: December 2019

The demanding for energy in Malaysia to use for all-purpose of small device charging has been developed. The purpose of this project is to develop portable solar storage (PSS) device with all the components of an off-grid solar station compact into a small portable handheld casing. The PSS is aimed for outdoor activity passionate such as hikers, campers and climbers that need a portable power charger that can charge their electronic gadgets while they carry on with their activities. The input current and voltage of the solar panel had been recorded over a span of two weeks. The generation of electricity is harvested from solar irradiation on 12 V and 18 V solar panel and stored upon 98 W energy storage beneath the solar panel. The power stored put on the test and capable to recharge up to 10,000 mAh capacity for one-time charging. As a comparison between 12V and 18 V solar panel, the result shows the average charging rate of the 12 V and 18 V solar panels could reach as high as 16.086 W/h and 13.35 W/h respectively which considered had reached 12.75% efficiency.
Optimization of ZnO nanorods growth duration for humidity sensing application
Authors: Hafiz Jali Mohd , Rafis Abdul Rahim Hazli , Helmi Mohd Yusof Haziezol , Md Johari Md Ashadi , Thokchom Siddharth , Wadi Harun Sulaiman
Published: December 2019

This paper described an optimization approach of ZnO nanorods growth duration based on humidity sensing scheme. The proposed structure comprises of silica microfiber integrated with Zinc Oxide (ZnO) nanorods coated glass surface. The silica microfiber was tapered into constant waist diameter of 10 µm using flame brushing technique. The glass surface was grown with ZnO nanorods using hydrothermal method for 6 hours, 9 hours, 12 hours, 15 hours and 18 hours growth time. ZnO nanorods growth time would affect morphological structures such as density which change the light absorption into the nanorods. Samples were exposed to the difference humidity level ranging from 35%RH to 85%RH to observe the change of ZnO refractive index on the glass surface resulting different light attenuation in the silica microfiber. It utilizes the unique features of the scattering and surface absorption capability of the microfiber and ZnO nanomaterials coated glass surface to alter the output light intensity. The reported results may contribute to the optimal ZnO nanorods growth time for humidity sensing application.
Q-switched in figure of 8 by using graphite flakes as saturable absorber
Authors: Alsaady Mofaq , Awang NA , Zaker Thoalfiqar A
Published: December 2019

In this study, a successful experiment has been reported on pulse compression in the Q-switched fiber laser by utilizing graphite flakes as a saturable absorber (SA). The sputter deposition method was used to deposited graphite flakes as SA, incorporated into the bore of the laser in order to compress the width of the pulse in the operation of Q-switching. The small repetition rate at 29.6 kHz was mentioned as the maximum power of the pump with the single-to-noise ratio (SNR) ∼30dB was required to compress the pulse. Accordingly, graphite flakes have the ability to be utilized as an effective S A in producing pulse compression and Q-switching mode, that will be may fixedly lead to further enhancement in the fiber laser pulsed.
Low magnetic field effect of circular conductors on a fiberoptic transmission system
Authors: Mohammed Firas S , Zaker Thoalfiqar A , Abdaljalil Rana Oday , Alsaady Mofaq M B
Published: December 2019

In a communication system that uses fiber optics, light wave transmissions respond to the influence of surrounding magnetic fields, thereby causing undesirable changes in the output signal. Thus, an important task in electrical engineering is analyzing polarization and intensity changes to protect sensitive data transmission systems from unintended sources of magnetic disturbance. In this study, we propose a signal processing method to evaluate fiber-optic transmission systems under the influence of a weak magnetic field. This method is conducted by performing experimental and theoretical measurements on the axis of light propagation using a laboratory setup and simulation software OptiSystem (version 7.0). Results show that the shape, size, and axial positions of the conductor plays a key role in strengthening the magnetic field influence on increasing the bit error rate and decreasing the Q factor of the communication system.
Samarium (III) oxide thin film as a saturable absorber for the passively Q-switched Tm-doped fiber laser
Authors: Rusdi K N , Hisyam M B , Rusdi M F M , Zulkipli N F , Latiff A A , Harun S W , Saidin N
Published: December 2019

We have demonstrated a passive Q-switched Thulium-doped fiber laser (TDFL using samarium oxide (Sm2O3) nanomaterial as saturable absorber (SA). The Sm2O3 based SA was fabricated by simply mixing the Sm2O3 powder solution with polyvinyl alcohol (PVA) solution. The homogeneously mixed solution was spread and dry to form a thin film. A piece of 1 mm x 1 mm of the SA thin film is sandwiched between two fiber ferrules and incorporated into a TDFL ring cavity for pulses generation. By controlling the loss and gain in the cavity, stable Q-switching operation was generated. The repetition rate was tunable from 17.62 kHz to 29.20 kHz by varying the pump power from 619 mW to 784 mW. The smallest pulse width of 3.54 µs and the highest pulse energy of 0.20 uJ were obtained at the highest pump power.
Microfibre deposited NiS2 for all-fibre optical thresholding
Authors: Li Shi , Yin Yu , Wang Pengfei
Published: December 2019

We demonstrate a microfibre deposited NiS2 for optical thresholding. By employing the fabricated NiS2 device, an all-optical thresholding function based on the saturable absorption effect has been successfully realized. The signal-to-noise ratio of the input pulse signal can be improved from 2.7 dB to 14.5 dB. The results achieved indicate that this NiS2-based microfibre device could be operated as an excellent nonlinear photonics device for all-optical signal processing.
Unprecedented recent late-summer warm extremes recorded in tree-ring density on the Tibetan Plateau
Authors: Duan Jianping , Wu Peili , Ma Zhuguo , Duan Yawen
Published: December 2019

Tree-ring records have shown a significant upward trend of late summer temperatures over the Tibetan Plateau (TP) in recent decades. More detailed instrumental observations over the TP have also shown an increase in warm extremes, especially in the high-altitude area. It is not clear whether the recent increase in occurrence of warm extremes on the TP reflects an amplification of recent temperature fluctuations or it relates to the long-term climate trend. This study aims to address the above question by analyzing long-term late summer (August–September) temperature extremes over the TP using temperature reconstructions derived from tree-ring maximum latewood density. Our results show that the recent frequency of late summer warm extremes was unprecedented over the past four centuries, while the occurrence of cold extremes in the instrumental interval was minimal. However, after the removal of long-term trend, the frequencies of both warm and cold extremes in the instrumental period are actually smaller than the pre-instrumental period, indicating a decreased variability of late summer temperatures. Thus, we conclude that the recent observed increase in warm extremes is related to the long-term warming trend, rather than an amplification of temperature variability. This finding implies that the persistent warming on the TP in the future might trigger much more frequent warm extremes with potential ecological and environmental effects.
Elucidating emissions control strategies for ozone to protect human health and public welfare within the continental United States
Authors: Lyu Congmeng , Capps Shannon L , Hakami Amir , Zhao Shunliu , Resler Jaroslav , Carmichael Gregory R , Sandu Adrian , Russell Armistead G , Chai Tianfeng , Henze Daven K
Published: December 2019

Ground-level ozone, which forms photochemically in the atmosphere from precursor emissions of oxides of nitrogen (NO
x
) and volatile organic compounds, is a criteria pollutant that harms human health and public welfare. For a representative summer episode, premature mortality and potential productivity losses (PPLs) of selected crops and trees attributable to ozone exposure have been quantified using ozone fields from the Community Multiscale Air Quality (CMAQ) model. We applied exposure-response models for the increased risk of premature mortality due to long-term exposure to ozone over a theoretical minimum risk exposure level (TMREL) and for the reduced accumulation of vegetative biomass for four crop species and eleven tree species using the W126 metric designed to capture impacts on plants. To elucidate which emissions contributed to these disbenefits, we applied adjoint-based sensitivity analysis, which efficiently estimates sensitivities of concentration-based metrics with respect to numerous emissions parameters simultaneously. The adjoint of CMAQ was applied to the continental US to calculate the influence of spatially-resolved ozone precursor emissions on the annual average, domain-wide daily maximum 8 h average over the TMREL (elevated MDA8), premature mortality attributable to exposure to ozone above the TMREL, and PPLs. These quantities provide the impact in terms of the percent reduction in precursor emissions. Additionally, locations where similar percent reductions in ozone precursor emissions would impact one or more endpoints greater than average have been identified. NO
x
emissions were found to contribute most to the three metrics. The distinct spatial patterns of emissions influences on public welfare disbenefits as compared to the elevated MDA8 and premature mortality suggest that the current regulatory averaging time motivates different emissions control strategies than those that could most directly protect public welfare.
Application of ductility exhaustion based damage model to predict creep rupture time of grade 92 steel
Authors: Alang N A , Razak N Ab
Published: December 2019

To accurately predict the creep rupture time of notched bar becomes a challenge to academia and structural engineer due to complex stress-strain distribution around the notch throat. This paper presents a Finite Element (FE) simulation employing ductility exhaustion based damage model to predict creep rupture time of multiaxial notched bar Grade 92 steel. Three different notch acuity, η = 2.5, 5.0 and 12.0 were simulated and the FE predicted rupture time was compared to the available experimental rupture data. The reduction of creep ductility due to geometrical constraint is considered during the simulation by employing the void growth model. Further reduction in ductility in long term period arises from internal microstructural changes or damage is also accounted. Furthermore, empirical-type exponential prediction model coupled with skeletal stresses is applied to provide upper/lower bounds for short and long term rupture data. It is found that the FE prediction agreed well with the experimental data. At short-term, notched bar ruptured is controlled by the von-Mises stress while at long-term the rupture is controlled by the maximum principal stress.
Thermal Comfort Study of a Classroom in Northern Malaysia: A CFD Approach
Authors: Suhaila H , Suhaimi I , Mohamed M A S , Mustaffa M T , Kartini A , Atikah A
Published: December 2019

A conducive environment is essential in creating an ideal condition for the impartment of knowledge. One of the essential parts of such a conducive environment is to have a thermally comfortable condition. A study was conducted to assess the thermal comfort in one of the classrooms of a university located in the northern most part of Malaysia. The particular classroom was randomly chosen from a total of 4 classrooms of the same size and condition. Measurements of the dimensions of the room together with temperature and velocity were taken to make the computational model and as boundary conditions for the Computational Fluid Dynamics (CFD) simulation. The simulation was conducted to visualize and predict the temperature distribution and flow pattern inside the classroom. The results of the simulation showed that there exists a non-uniform circulation of cold air from the air-conditioning outlet to the rest of the classroom. The distribution of the cold air seems to be limited to only the location under the air-conditioning outlet making it thermally uncomfortable there. Hence, it is recommended to either reduce the airflow velocity coming out of the air-conditioning outlet or change the size or location of the air-conditioning outlets.
Investigation on the effect of drilling parameters on tensile loading of fibre-metal laminates
Authors: Azwan S , Sahira N I , Abdullah M R , Yahya M Yazid
Published: December 2019

This study conducted to investigate the effect of different drilling parameters on the strength of vacuum infusion fibre reinforced epoxy resin-based fibre metal laminates (FML). The effect of several parameters such as the speed of drilling (1050, 2020, and 2750 rpm) and feed rate of (0.05, 0.1, and 0.15 mm/rev), and the thickness of FML on the strength of the composite materials were studied experimentally. The FML has been analysed under static loading. Drilling at lower spindle speed and lower feed rate results in better strength than higher spindle speed and feed rate. Then, the thicker FML gives more strength compare to the one with less thickness.
Effect of synthetic fibres on tensile properties of Napier fibres reinforced epoxy composites
Authors: Ridzuan M J M , Majid M S Abdul , Khasri A , Cheng E M , Sulaiman M H , Basaruddin K S
Published: December 2019

This paper present the effect of synthetic fibres on the tensile properties of Napier fibres reinforced epoxy composites. The composites were fabricated using the vacuum infusion method, which the Napier grass fibre placed between the synthetic fibres, then mixed the epoxy resin with a ratio of fibres and epoxy was 70:30. There were four different types of composite samples were fabricated based on various volume fractions. The samples were manufactured using vacuum infusion process. The composites are tested using a universal testing machine according with ASTM standard D638. The tensile strength of the hybrid synthetic/Napier fibre reinforced epoxy composites increased as the content of the synthetic fibre content increased. The tensile properties of the hybrid carbon/Napier reinforced epoxy composites were observed higher than the hybrid glass/Napier reinforced epoxy composites.
Implementation of multi-component dusty-gas model for species transport in quasi-three-dimensional numerical analysis of solid oxide fuel cell. Part I: hydrogen fuel
Authors: Tan W C , Iwai H , Kishimoto M , Yoshida H
Published: December 2019

Quasi-three-dimensional numerical model of solid oxide fuel cell, which assumes constant physicochemical properties within the cell components in the thickness direction, typically employs a simple gas diffusion model for species transport in the porous electrodes, such as the Fick’s model. In this study, a three-dimensional grid system is introduced in the anode layer and coupled with the quasi-three-dimensional solid oxide fuel cell model. The multi-component dusty-gas model is implemented to solve the conservation of species on this three-dimensional grid system. The results with the developed model are compared with experimental data obtained under hydrogen fuel. The obtained results show that the dusty-gas model can accurately predict the transport of gas species in the porous anode.
A short review on the use of coconut shell powder as filler in cement concrete
Authors: Nadzri S N I H A , Sultan M T H , Shah A U M , Safri S N A
Published: December 2019

Environmentally-friendly composites had been the interest of researchers nowadays. Therefore the use of natural sources to gradually replace the conventional materials had been rapidly developed. Besides the use of natural fibres as reinforcement in polymer matrix composites, the use of fillers from natural sources, such as rice husk and corn cobs, was implemented in ceramic matrix composites. Solid waste like coconut shell is one of the potential material to be used as filler in this composites. Coconut shell in powder forms is usually used together with cement to produce high strength, more durability and lightweight concrete for structural component in construction area. Based on this review paper, coconut shell concrete showed comparable mechanical properties to the conventional concrete, in terms of its compressive strength. These properties suggested coconut shell powder as potential material to replace course aggregate in concrete.
Static analysis on Malaysian Yankee’s pineapple leaf fiber/epoxy composite
Authors: Najeeb M I , Sultan M T H , Shah A U M , Safri S N A
Published: December 2019

The static analysis on pineapple leaf fibre (PALF) reinforced epoxy composites was carried out in this study. The effect of fiber alignment in X and Y axis were studied while maintaining total fiber loading of 10% by weight. The bending and compression strength were analyzed by performing flexural and compression test. The composite properties was strongly influence by the fiber orientation where Y axis shows improvement about 97% in bending and 5.3% in compressive strength compared to neat epoxy. However, as for X orientation bending test shows lower bending strength compared to neat epoxy but improve 4% in compressive strength. It can be concludedthat the fiber alignment in Y-direction is more suitable to be utilized for automotive interior or household applications that demand high strength properties.
Receding height of water droplet in the film boiling regime
Authors: Illias S , Hussain S , Rosman N A , Abdullah N S , Shaiful A I M , Omar M N B , Ismail K A , Ani H
Published: December 2019

The purpose of this research was to study and investigate the receding height of water droplet after it impinged on hot aluminum surface. On top of that, we also investigated the relationship between this receding phenomenon and residence time of water droplet. Degassed and distilled water was used as a droplet. The droplet diameter was maintained at 4.0 mm and the impact height was set to be around 65.0 mm corresponding to impact velocity of 1.129 m/s. The liquid temperature was kept around 16 °C corresponding to liquid subcooling of ΔT

sub
= 84 K. The material selected in this experiment was aluminum surface. The surface had been polished until it became a mirror polished surface. The dimensions of the material surface were 30.0 mm in diameter and 8.0 mm in height. The phenomena were recorded at 10,000 frames per second using a high speed video camera. As a result, it was observed that the receding height during film boiling regime was almost similar to each other even the surface temperature was different. Furthermore, the residence time during the experiment was also close to the theoretical calculation.
Analysis of insertion and removal torque loading for miniscrew and miniplate skeletal anchorage
Authors: Khor Z H , Daud R , Kamarrudin N S , Ibrahim I , Mat F , Basaruddin K S
Published: December 2019

Mini-Implant such as miniscrew and miniplate is used as a stabilizer in stable the crack occurs at the mandibular bone and maxillary bone for recovery. Reducing the screw loosening may reduce the trauma of insertion and removal that able to increase the rates of osseointegration. This paper presents the investigation of stress transfer between the interaction mini-implant and bone during applied in insertion and removal torque regards to stress distribution between mini-implant and bones. The finite element simulation involves three different materials mini-implant such as Titanium Alloy, (TiA), Stainless Steel, (SS) and Magnesium Alloy, (MgA). The result identified that the best material of mini-implant used to insert at mandibular bone is Titanium, (TiA) with the moment of 90 Nmm to perform high 0.70 STP value and average SEDTP of 2.60 compared to other materials. Whereas, for the material of mini-implant used to inserted at maxillary bone is Magnesium Alloy, (MgA) with the moment of 100 Nmm to perform high 1.11 STP value and average SEDTP of 1.20.
Biomechanical analysis of patient-specific femur model of osteogenesis imperfecta with cortical and cancellous bone
Authors: Tan L C , Som M H Mat , Basaruddin K S , Yazid H , Daud R , Awang M S
Published: December 2019

Osteogenesis imperfecta (OI) is a fragile bone disease characterized by easy fractures. The femur consists of cortical and cancellous bone, each with different mechanical properties. Bone fractures often occur throughout patients’ lifetime. However, doctors still have no quantitative method to predict fractures. This project’s purpose is to investigate the mechanical behaviour of patient-specific OI femur from the finite element analysis. The fracture risk in daily activities (ADL) were examined. All the stress values were judged by the fracture criteria, assumed as 115 MPa. The exercises that exerted force more than 6 times of body weight could cause fractures. Cancellous bone was not affected in any case of ADL. The effects of force and stress on cancellous bone and its impact on fracture risk are negligible.
Tribological properties of DLC coating under lubricated and dry friction condition
Authors: Sulaiman M H , Farahana R N , Mustaffa M N , Bienk K
Published: December 2019

Increasing demands on reducing abundant use of environmentally hazardous lubricants like chlorinated paraffin oil in production motivates extensive research on dry friction condition. However, the dry friction condition is not favourable, and it causes high friction and severe wear problems. This paper presents the tribological behaviour of a new hard coating, namely double-layer DLC/TiAlN, deposited onto the tool steel surface via a Physical Vapour Deposition (PVD) process. A pin-on-disk tribometer was used to study the long-term performance of DLC/TiAlN coated tool steel under lubricated and dry friction conditions. Surface damage after the experiment was observed by using a light optical microscope (LOM) and also, analysed by measuring wear scar profiles with a tactile roughness profilometer. The results were compared with uncoated tool steel. Based on the experimental result, applying the DLC/TiAlN coating to the tool steel surface has led to a significant reduction of friction and almost no wear scar was observed. The study proved that the DLC/TiAlN coating contributes to the better wear life of the tool steel, thereby improving the tool lifetime.
Laboratory development of low speed wind tunnel for educational purposes
Authors: Siregar R A , Umurani K
Published: December 2019

In this paper presents the design and development of wind tunnel for education purposes. The wind tunnel is designed as an open-type, low speed, able to provide wind speeds up to 20 m/s and maximum turbulent intensity is 5%. A 70 cm tube axial fan is driven by a 3 hp motor using a variable frequency drive to allow continuously variable wind speeds. The size of testing chamber is about 40 cm by 40 cm, large enough to conduct experiments such as drag coefficient, airfoil and wing. Preliminary test of air flow in testing chamber shows that wind tunnel is particularly suitable not only for education but also for aerodynamic researches.
CFD analysis of hydrodynamic lubrication effects of micro textured surface
Authors: Sulaiman M H , Zaid M F S , Farahana R N , Ridzuan M J M
Published: December 2019

A great number of lubricated mechanical components everywhere in life. Improvement in efficiency would lead to greater cost savings in many engineering applications. In the present paper, an approach to increase the efficiency in hydrodynamic lubrication for applications in metal forming processes by surface texturing was studied using Computational Fluid Dynamics (CFD) simulation. A two-dimensional fluid domain containing a flat upper wall with a tangential velocity and a static lower wall containing an oblong groove of the same sizes was studied. This includes the effect of varying distances between grooves on lubrication. With an isothermal lubrication flow condition and parallel walls, the pressure in the lubricant domain produces largest load carrying capacity and wall shear force, indicating large contact area contributes to an increase of frictional force. The present study revealed that the positive influence on hydrodynamic lubrication performance can be achieved by introducing a textured surface. Larger distance between the grooves has effectively produced a pressure build-up in the lubricant domain introducing a larger load carrying capacity. It is seen that a load carrying capacity exists for a small distance between the grooves.
Effect of surface treatment on drag coefficient of free-falling solid sphere in water
Authors: Mohamad M Sofwan , Dover C M Mackenzie , Sefiane K
Published: December 2019

The study aims to examine the influence of different surface treatments on the drag coefficient of free-falling spheres in water. The spheres used in the experiment are classified into four categories and labelled as: ref – no surface treatment, FDTS – coated with hydrophobic perfluorodecyltrichlorosilane (FDTS) coating, E8 – 8 minutes etched in ferric chloride (FeCl3) and E32 – 32 minutes etched in FeCl3. No significant difference is observed in drag coefficient of the etched spheres compare with the reference sphere. However, the FDTS sphere’s drag coefficient was increased by 13%.
Dynamic oblique crushing of single and bi-tubular aluminium conical tubes with imperfection
Authors: Mat Fauziah , Nazreen Hani Mohammad Syarul , Md Rejab Md Noor Arib
Published: December 2019

This paper aims to study the crashworthiness response of single and bi-tubular aluminium conical tubes subjected to oblique loading. The influence of imperfection on crashworthiness criteria is studied by introducing circular cutouts to the single and bi-tubular conical tubes. The explicit finite element (FE) code LS DYNA is employed to develop the FE model of the tubes. Satisfactory agreement between the developed FE model and previous experimental work has been obtained. The validated model is then employed to investigate the influence of imperfection on the tubes based on internal energy at maximum deformation. The finding shows that with the introduction of cutouts, the energy absorption capability and Specific Energy Absorption (SEA) of bi-tubular tubes are improved as high as 3.43 % and 3.44 %, respectively compared to the single tubes. Compared to the tubes without cutouts, there is a reduction of the internal energy and the SEA of the tubes with cutouts. For bi-tubular tubes, the reduction of the energy absorbed is only 6.41 % thus implies that bi-tubular tubes are better than single tubes when subjected to oblique loading. The similar pattern is also found in the SEA. Furthermore, the increase in loading angle, α reduces the internal energy and the SEA.
Evaluation of square deep drawn AA6061-T6 blank based on thinning pattern
Authors: Yusop N M , Abdullah A B
Published: December 2019

Deep drawing can be generally described as a process of converting a metal sheet into a desired shape and geometry. Material flow and formability of the blank depends on the die and the punch geometries and it is important to predict the material behavior during square deep drawing to reduce possibility of defect and part rejection. In this research, a 3D Finite Element (FE) model is developed to simulate the square deep drawing process of an AA6061-T6 material using ANSYS Explicit Dynamics. The developed model can be used to predict the thinning pattern of the blank especially at the corner area. This research focus on the effect of design parameters namely punch corner radius (R1), punch nose radius (R2), die corner radius (R3) and die shoulder radius (R4) towards thinning pattern.
Point Cloud Data Segmentation Using RANSAC and Localization
Authors: Mohd Isa S. N. , Abdul Shukor S. A. , Rahim N. A. , Maarof I. , Yahya Z. R. , Zakaria A. , Abdullah A. H. , Wong R.
Published: December 2019

In this paper, we present 3D point cloud data segmentation from a Terrestrial Laser Scanner (TLS) using RANSAC and localization approaches. Our work is using the real world data acquired from outdoor and indoor scene of Tawau Bell Tower (also known as the Belfry), one of the heritage building located in Sabah. We adapt the methods to segment ground and nonground data for data reduction. Based on the non-ground information and geometrical constraint, the data managed to show the building structure. The aim is to use and handle a smaller set of data rather than using the entire point cloud data in processing the region of interest. This will also help to reduce processing time as point cloud data from a TLS is usually large in size. The ground plane was fitted with RANSAC algorithm restricted by distance to describe the geometrical of the plane. As a result, the point cloud data was reduced to the environment around Bell Tower and able to highlight the region of interest. Building segmentation is then retrieved from the reference centre location to form a bounding box and data were organized using kd-tree to denote the Bell Tower structure. The framework is tested for outdoor and indoor scan of the Bell Tower and able to segment the data appropriately.
Classification of different materials for underground object using artificial neural network
Authors: Ali H , Ahmad Firdaus A Z , Azalan Mohd Shuhanaz Zanar , Kanafiah S N A M , Salman S H , Ahmad M R , T Amran T Sarah , M Amin M Syafiq
Published: December 2019

Ground Penetrating Radar (GPR) is widely used for non-destructive investigation of the shallow subsurface exploration especially in locating the buried infrastructure such as pipes, cables and road inspections. However, the interpreting hyperbolic signature of buried object in GPR images remains a challenging task. Therefore, this paper presented the classification of different materials based on GPR images using artificial neural network (ANN). In this research, GPR images so called the B-scan radargram represented by hyperbolic signature are firstly acquired and pre-processed. Then, the hyperbolic signature features are extracted using statistical techniques. The extracted features is then fed up as input to the multilayer perceptron (MLP) neural network classifier. A series of experiments have been conducted based on extracted hyperbolic features of different materials and shapes. Based on the results, the proposed method in classifying different materials based on GPR images using neural network showed promising results.
Design and Development of Three-Phase Voltage Source Inverter for Variable Frequency Drive
Authors: Nurhaida A S , Ahmad Firdaus A Z , Kamarudin Kamarulzaman , Azmi S A , Ridzuan M J M , Hafis S M
Published: December 2019

Three phase induction motors are the workhorse of industry. Variable speed operation of the motor enables substantial energy savings through implementation of variable frequency drives. This project concerns on the design and implementation of three-phase voltage source inverter (VSI) for variable frequency drive. The focus was to generate variable frequency output suitable to be fed to the induction motor for the purpose of variable speed control. SPWM signal was generated through SIMULINK algorithm. The VSI circuit was designed, fed with SPWM trigger signal and simulated for variable frequency output in terms of line-to-neutral and line-to-line voltage across R-L load. In the experimental setup, the real VSI system was developed, the SPWM trigger signal generated through SIMULINK and interfaced to hardware using Arduino microcontroller. The output is dropped across resistive load and parameters line-to-neutral and line-to-line voltage was measured. Three set of output voltage with frequency of generated at 20Hz, 50Hz and 70Hz. Thus, experimental result validated that variation of frequency of voltage output of the VSI has been successfully achieved.
Effect of electromagnetic induction spectroscopy of femur bone on electromagnetic signal strength
Authors: Amran M. , Daud R. , Ali Hassan M.K. , Zakaria Z. , Omar M. I. , Mat F.
Published: December 2019

Bone implant is a promising technique to heal the fracture site where it focusing to stabilize and support the bone. Improvement in bone implant are required in order to ensure better healing process because some failures may happen due to the loss of implant stability. Previous studies showed there are lack of investigation on bone implant. Early detection of screw implant loosening is crucial for faster repairing and a healthy ready-to-operate. The purpose of this study is to investigate the signal strength of electromagnetic field induction on human bone by employing a single channel magnetic induction spectroscopy using flat spiral coil sensor. This study also to evaluate the various type of coil sensitivity of the magnetic induction spectroscopy on femur bone. The electromagnetic field induction will be analyse using the COMSOL Multiphysics simulation software to collect the data of received signal strength. The promising experimental results suggested the feasibility of the proposed electromagnetic induction spectroscopy.
Electrochemical Techniques-Based approaches for Mycobacterium Tuberculosis Detection: Last Decade Review
Authors: Alfarhan K , Zakaria A , Yusof N , Zakaria S , Abdullah J , Kamarudin L , Azmi  , Ariffin N
Published: December 2019

Mycobacterium Tuberculosis (MTB) is a common airborne infectious disease that leads to millions of deaths every year worldwide. It is still one of the top ten causes of death and the victims of TB are more than HIV/AIDS in 2017. Traditional approaches for MTB detection are either take a long time, unreliable or high cost. The electrochemical techniques (ECTs) as improved and inexpensive approaches to detect the MTB. Many of ECTs were used in MTB detection such as differential pulse voltammetric (DPV), cyclic voltammetric (CV), square wave voltammetric (SWV), amperometric and impedimetric. Principle of the MTB detection using ECTs depends on DNA hybridization of the MTB on the working electrode of ECTs. The researchers developed biosensors or aptasensors and used them for ECTs analyzing to detect the MTB. They developed various biosensors from various composite and DNA probes but all the developed composite of the biosensors were used to coat the electrodes that used in ECTs. Many types of electrodes and electrolytes were used in MTB detection. The most used ECTs in MTB detection is DPV and CV while the least used is amperometric. The ECTs for MTB detection achieved high sensitivity, reliability, low detection time and very low detection limits.
Metal shape classification of buried object using multilayer perceptron neural network in GPR data
Authors: Kanafiah S N A M , Ali H , Ahmad Firdaus A Z , Zanar Azalan M S , Jusman Y , Khairi A A , Ahmad M R , Sara T , Amran T , Mansor I , Shukor S A A , Cheng E M , Fook C Y
Published: December 2019

Ground penetrating radar (GPR) is a non-destructive tool for subsurface investigation becomes an emerging trend in many applications especially in detecting infrastructure utilities. However, interpreting of GPR data in terms of target’s geometry is remained a challenging task due to the existence intra/inter-class variations and subtle changes of hyperbolic signature pattern in GPR data. To addressed this issue, this paper proposes to classify the basic shape (i.e. cubic, cylindrical and disc) of buried object using multilayer perceptron neural network. The GPR raw data firstly is pre-processed based on A-scan and B- scan GPR data. Then, the combined statistical features with gray level co-occurrence matrix (GLCM) and Hu moment invariants are extracted from A-scan and B-scan. The extracted features are then fed as input to multilayer perceptron to classify the shapes (cubic, cylindrical and disc) of buried object. Based on the experiment conducted, the highest recognition rate has been achieved is about 83.3%. Thus, the proposed method of using combined statistical with GLCM and Hu moment invariants features to classify shape of buried object using multilayer perceptron is promising.
Monitoring Oil Palm Tree Health–A Review
Authors: Hoe J H , Shukor S A A
Published: December 2019

Oil palm is known as one of the most important resources in Malaysia which able to be exported to other countries. Oil palm, also known as “Elaeis guineensis”, has many usages and benefits. To ensure the productivity and quality of the oil palm, the health status of the tree needs to be monitored, as they can be prone to various diseases. This paper is going to discuss current methods other researchers have adapted that able to be used in monitoring oil palm trees health. In addition, some analyses and conclusion were drawn to address related issues in the area.
Gas source localization accuracy: A comparison between conventional, weighted arithmetic mean and kernel-based gas distribution mapping methods in small indoor area
Authors: Yeon A S A , Visvanathan R , Kamarudin K , Mamduh S M , Zakaria A , Kamarudin L M
Published: December 2019

This work focuses on comparing gas source localization accuracy of three types of gas source localization methods which are the conventional method, weighted-averaging mean method and variance map from DM+V method. Gas source localization accuracy in this work means the distance error between the calculated source location and the actual source location. All methods were implemented offline using the measurements collected from real-time gas source localization experiments that were done beforehand. The dataset consists of gas sensor measurements, and mobile robot’s location in a 3m by 6m test area. The goal of the work is to shine a light on why recent works in the field are more focusing on improving probabilistic and map-based algorithms. This work also shows how the kernel size of kernel-based gas distribution mapping might affect the gas source localization accuracy in a small indoor area.
Human Identification through Kinect’s Depth, RGB, and Sound Sensor
Authors: Shunmugam P , Kamarudin K , Mosed A A A , Shukor S A A
Published: December 2019

Human identification is a very important subject in computer field and has been researched widely. This paper proposes human identification system based on Kinect’s individual sensor as well as combination of all its available sensors. In the first part of the project, each sensor on the Kinect (i.e IR depth sensor, RGB camera and microphones) was used for skeleton recognition, face recognition and speech recognition respectively. Then, these individual recognition methods are combined as step-by-step process into a multi-sensor recognition system. Few experiments were carried out to test the reliability of the developed human identification systems. The results show that multi-sensor based human identification system is highly efficient compared to the single-sensor system. This is because, multi-sensor recognition system involves many recognition stages as each recognition stage needs particular biometric information of the user.