bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optical comb filter generation in micro cavity employing Zinc Oxide based film
Authors: Burhanuddin H M , Zuikafly S N F , Ibrahim A A , Ambran S , Mikami O , Fujikawa C , Ahmad F 
Published: December 2019

Abstract
Optical comb filter generation was proposed and experimentally demonstrated by using Fabry-Perot interferometer in micro cavity. The change of length of Fabry-Perot interferometer modifies the interference pattern with the adjusted length is from 0 um to 350 nm. The parameter of the generated comb such as free spectral range, extinction ratio, quality factor and finesse was recorded with and without Zinc Oxide based film (nano powder and nano particles). The stable comb filter was generated with a length of 100 um for both Zin Oxide-based film and 150 um for the uncoated mirror. At the maximum length of 350 nm, Zinc Oxide nano particles film generates most stable optical comb filter with free spectral range, extinction ratio, quality factor and finesse of, 3 nm, 8 dB, 1298 and 2.5, respectively.
Q-switched erbium-doped fiber laser employing gold thin film saturable absorber
Authors: Yuzaile Y R , Zakaria Z , Zalkepali N U H H , Awang N A , Latif A A , A H AH , Nik Mahmud N N H E 
Published: December 2019

AbstractThis research demonstrates an erbium-doped fiber laser (EDFL) which was passively Q-switched by gold thin film saturable absorber (SA). A very simple technique was used to fabricate the SA, in which the gold was directly deposited on the fiber end face through DC magnetron sputtering at 120 mA of sputtering current. The SA was then inserted into the single ring cavity and achieved Q-switching at a threshold pump power of 38.8 mW. By gradually increasing the pump power from 38.8 mW to 119.3 mW, the repetition rate increases from 11.34 kHz to 21.72 kHz. Meanwhile, the pulse duration decreases from 13.91 us to 7.44 us. The maximum achievable pulse energy was 13.28 nJ. This research further expands the application of gold thin film S A to the field of Q-switched pulsed fiber laser.
Influence of concentration on the geometry of ZnO nanostructures prepared by chemical bath deposition
Authors: Rosli N , Halim M M , Hashim M R , Maryam W 
Published: December 2019

Abstract
Zinc Oxide (ZnO) nanostructures such as nanorods (NRs), nanowalls (NWs) and nanoflakes (NFs) were successfully grown on a glass substrate via chemical bath deposition (CBD) method by varying solutions concentration (0.01 M, 0.05 M, 0.10 M, 0.15 M, 0.20 M and 0.25 M). Effect of CBD concentration on the growth and morphology of ZnO nanostructures are dignified. The structural and optical properties of ZnO NRs, NWs, and NFs were investigated by Field Emission Scanning Electron Microscope (FESEM), energy-dispersive X-ray (EDX), X-Ray Diffraction (XRD), and UV-Visible (UV-Vis) analyses. Results reveal that as the CBD concentration increases, FESEM images showed differ top-down morphology of ZnO nanostructures from NRs, NWs to NFs. Likewise, the alignment of ZnO cross-section evolved from randomly oriented to vertically oriented. As revealed by EDX, the stoichiometric ratio of Zn:O were mostly towards 1:1. From XRD analyses, the preferred structure was wurtzite hexagonal with c-axis orientation along (002) plane. The UV-Vis analysis exposed the optical band gap energy closes to the standard energy gap value of ZnO at 3.37 eV. Thus, this work introduces a variable geometry of ZnO nanostructures (NRs, NWs, and NFs) grown on glass with high structural and optical quality as standard ZnO. The fabricated materials are potential candidates for investigating random lasing in ZnO from different structural geometry.
Tunable passively Q-switched fiber laser of graphite flakes saturable absorber
Authors: Mahmud Nik N H E N , Esa Fahmiruddin , Awang Noor A , Zakaria Zahariah , Yuzaile Yushazlina R , Zalkepali Noor U H H 
Published: December 2019

Abstract
This study demonstrated the performance of a passively Q-switched fiber laser by using graphite flakes at different EDF absorption which are EDF 1 and EDF 2 at 5.09 dB/m and 7.28 dB/m, respectively. The system is designed as a single ring cavity by employing a graphite flakes saturable absorber (SA) with 23.82% of saturable absorption. The experimental result shows that a wide-band tunable cover from 1544 nm to 1560 nm and 1552 nm to 1570 nm for EDF 1 and EDF 2 respectively. The EDF 2 is the best gain medium due to the conventional wavelength band at C band and L band region.
A study on relative humidity sensors using PVA and PMMA coating
Authors: Harith Zuraidah , Adnan Abdullah Zain Huda , Batumalay Malathy , Wadi Harun Sulaiman 
Published: December 2019

Abstract
Simple relative humidity sensors are demonstrated using tapered silica microfibers. The silica microfibers are tapered using flame brushing method to reduce the fiber’s waist diameter from 128 micrometers to 2.6 micrometers. The tapered silica microfibers were then coated using polyvinyl acetate (PVA) and polymethyl methacrylate (PMMA) before it was used to sense the relative humidity. The tapered silica microfiber coated with PVA performed better compared to tapered silica microfiber coated using PMMA. The tapered silica microfiber with PVA based sensor has better sensitivity of 0.3023 dB/RH%.
Q-switched erbium-doped fiber lasers based on copper nanoparticles saturable absorber
Authors: Ismail E I , Ahmad F , Ambran S , Latiff A A , Harun S W 
Published: December 2019

Abstract
We reported a generation of passively Q-switching pulses in an erbium-doped fiber laser by exploiting copper nanoparticles polyvinyl alcohol polymer composite (CuNP-PVA) based saturable absorber (SA). The modulation depth and the saturation power intensity of the CuNP-PVA film are calculated as 18 % and 0.021 kW/cm2, respectively. A maximum repetition rate of 104.2 kHz, the shortest pulse width of 5.1 µs and pulse energy up to 20.4 nJ was observed at 1558 nm wavelength.
Recalibrating climate prospects
Authors: Lovins Amory B , Ürge-Vorsatz Diana , Mundaca Luis , Kammen Daniel M , Glassman Jacob W 
Published: December 2019

Abstract
IPCC’s 2018 Special Report is a stark and bracing reminder of climate threats. Yet literature, reportage, and public discourse reflect imbalanced risk and opportunity. Climate science often understates changes’ speed and nonlinearity, but Integrated Assessment Models (IAMs) and similar studies often understate realistic mitigation options. Since ∼2010, global mitigation of fossil CO2—including by often-uncounted modern renewable heat comparable to solar-plus-wind electricity—has accelerated to about the pace (if sustained) needed for a 2 °C trajectory. Mitigation has uncertainties, emergent properties, feasibility thresholds, and nonlinearities at least comparable to climate’s, creating opportunities for aggressive action. Renewable electricity’s swift uptake can now be echoed as proven integrative design can make end-use efficiency severalfold larger and cheaper, often with increasing returns (lower cost with rising quantity). Saved energy—the world’s largest decarbonizer and energy ‘source’ (bigger than oil)—can then potentiate renewables and cut supply investments, as a few recent efficiency-centric IAMs confirm. Optimizing choices, combinations, timing, and sequencing of technologies, urban form, behavioral shifts, etc could save still more energy, money, and time. Some rigorous engineering-based national studies outside standard climate literature even imply potential 1.5 °C global trajectories cheaper than business-as-usual. A complementary opportunity—rapidly and durably abating hydrocarbon industries’ deliberate upstream CH4 releases from flares and engineered vents, by any large operator’s profitably abating its own and others’ emissions—could stabilize (or more) the global methane cycle and buy time to abate more CO2. Together, these findings justify sober recalibration of the prospects for a fairer, healthier, cooler, and safer world. Supported by other disciplines, improved IAMs can illuminate this potential and support its refinement. Ambitious policies and aggressive marketplace and societal adoption of profitable new abatement opportunities need not wait for better models, but better models would help them to attract merited attention, scale faster, and turn numbing despair into collectively powerful applied hope.
Snowpack properties vary in response to burn severity gradients in montane forests
Authors: Maxwell Jordan , St Clair Samuel B 
Published: December 2019

Abstract
Wildfires are altering ecosystems globally as they change in frequency, size, and severity. As wildfires change vegetation structure, they also alter moisture inputs and energy fluxes which influence snowpack and hydrology. In unburned forests, snow has been shown to accumulate more in small clearings or in stands with low to moderate forest densities. Here we investigate whether peak snowpack varies with burn severity or percent overstory tree mortality post-fire in a mid-latitude, subalpine forest. We found that peak snowpack across the burn severity gradients increased 15% in snow-water equivalence (SWE) and 17% in depth for every 20% increase in overstory tree mortality due to burn severity. Snowpack quantity varied greatly between the two winter seasons sampled in this study with 114% more snow in 2016 versus 2015, yet the effect of burn severity on snowpack remained consistent. These data support previous studies showing increases in peak snow depth and SWE in burned forests but for the first time provides novel insights into how snow depth and SWE change as a function of burn severity. We conclude that changes not only in the frequency and size of wildfires, but also in the severity, can alter peak snow depth and SWE, with important potential implications for watershed hydrology.
Corrigendum: GAN-Based Augmentation for Improving CNN Performance of Classification of Defective Photovoltaic Module Cells in Electroluminescence Images (IOP Conf. Ser.: Earth Environ. Sci. 354 012106)
Authors: Luo Z , Cheng S Y , Zheng Q Y 
Published: December 2019

The corresponding author acknowledges not correctly referencing the content taken fromhttps://github.com/zae-bayern/elpv-dataset. The author apologises for the error.Corrigendum published: 29 November 2019
Preparation and characterization of chromium metal organic framework with trimesic or terephthalic acid in carbon dioxide adsorption
Authors: Chong K C , Foo P L , Lai S O , Thiam H S , Lee S S , Lau W J 
Published: December 2019

Abstract
Greenhouse gases (GHGs) have greatly changed the global climate in the recent year. Metal organic frameworks (MOFs) is one of the solutions which can be utilized as gas adsorbents to capture carbon dioxide (CO2), the main contributor of greenhouse effect. MOF possesses good CO2 adsorption ability attributed to its high surface area to volume ratio and pore size. Nevertheless, the success of the MOF is greatly depend on the fabrication parameter such as fabrication methods, type of metal oxide, type of organic linkers used and the molar ratio of the reactant. In this study, chromium (VI) oxide, trimesic acid and terephthalic acid were used to fabricate MOFs by solvothermal method to investigate the performance of CO2 adsorption. The characterization tests by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) shows that Cr-TMA-1:5 amongst the rest of the fabricated MOF possess the shape of small irregular diagonal with highest surface area to volume ratio which was ideal in CO2 adsorption. Furthers, the result CO2 adsorption test carried by thermogravimetric analyser (TGA) suggested the MOF Cr-TMA-1:5 possesses the highest the CO2 adsorption capacity recorded at 0.099 mmol/g. This had revealed that MOFs composed of chromium (VI) oxide and trimesic acid possess the potential to be applied in CO2 adsorption.
Theory and derivation of unsymmetrical rotor equation of the foil-air bearing rotor system and its validation with experiment data
Authors: Hassan M F 
Published: December 2019

Abstract
This manuscript presents the theory and derivation of rotor equation using rigid body modelling used to validate the modal transformation approach for solving foil-air bearing rotor system. Numerical coefficient of the rotor equation for both methods only different less than 3%. The reasonable correlation in term of orbit’s orientation with experimental data, has proved that the rotor was correctly modelled and adapted with simultaneous solution technique and modal model of foil structure.
Fundamental study on the optimal path of centrifugal pendulum vibration absorbers in automatic transmissions
Authors: Ryu T , Nakae T , Matsuzaki K , Ozaki J 
Published: December 2019

Abstract
In recent years, high-power and low-cylinder engines have seen increasingly widespread use. These engines produce a strong torsional vibration due to engine combustion. Furthermore, automatic transmissions necessitate the use of a lock-up clutch system that directly links the engine and gear train when the engine rotational speed is low. Using a torsional spring called a lock-up damper in the torque converter is not sufficient to absorb the torsional vibration. Therefore, the centrifugal pendulum vibration absorber (CPVA) has been developed to suppress the torsional vibration. The natural frequency of a CPVA is proportional to the engine rotational speed, and it is expected to suppress the torsional vibration over a wide range of speeds. However, the natural frequency of the CPVA varies because of the nonlinearity when the vibration amplitude of the CPVA is large. In this study, the optimal path of the CPVA to suppress the torsional vibration of the engine was investigated.
Effect of metal cutting fluid (MCF) conditions on tool wear and thrust force in drilling Ti-6Al-4V using coated carbide tools
Authors: Rashid R A , Murad M N , Hamidon R , Shariffuddin S 
Published: December 2019

Abstract
Titanium alloy (Ti-6Al-4V) is well known as difficult to cut material due to their low machinability rating. Machining Ti-6Al-4V generate high cutting temperature close to the cutting edge of the tool. The high cutting temperature, mostly during the deformation process and friction at the tool–chip and tool–workpiece interfaces. This circumstances will lead to the rapid tool wear. This study focuses on the growth of tool wear and development of the thrust force. Drilling tests were conducted using coated (TiAlN) carbide tool with diameter of 6 mm under two different condition of metal cutting fluid (MCF). The MCF used were minimum quantity lubrication (MQL) and minimum quantity cooling lubrication (MQCL). The outcomes of this study indicates MQL performed better coolant-lubricant effect during drilling Ti-6Al-4V as the results of thrust force development are consistent with the trends of tool wear growth.
Evaporation lifetime and boiling curve on hemispherical stainless steel (304) surface
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

Abstract
The purpose of this research is to study and investigate the evaporation lifetime and boiling curve on hemispherical heated surface. The selected material was stainless steel (304). A nearly perfect and smooth hemispherical surface was developed by using EDM die sinker. For the test liquid, distilled water was used during the experimental work. The average droplet temperature was 31.36 °C corresponding to liquid subcooling ΔT

sub
= 68.64K. Based on the theoretical calculation, the diameter of the water droplet was approximately 5.00 mm. Meanwhile, the impact height was approximately 65.0 mm corresponding to the theoretical impact velocity of 1.129 m/s. The material was heated using a digital hot plate which was able to give an accurate reading and stable temperature fluctuation during the heating process. The temperature ranged from a low temperature of T

w
= 100 °C to a high temperature of T

w
= 300 °C. As a result, the boiling curve showed a similar pattern of other experimental work that consists of two (2) important points which are Critical Heat Flux(CHF) and Leidenfrost temperature.
Frontal impact on bus superstructure as per UNECE R29 and NCAP
Authors: Afripin M A A , Zainudin A Z , Sahar M A H F M , Yusof M 
Published: December 2019

Abstract
Frontal crash for the large vehicle is less severe compared to the lightweight vehicle due to the height position of the driver compartment in the vehicle which sits well above the impact area in any accident involving a passenger vehicle. Due to this reason, most of the coachbuilder does not include crumple zone in their design as what the car’s manufacturer did. However, in the case of frontal collision between two large vehicles or with the rigid wall, the possibility of energy absorption of the structure is very low and the remaining energy will be transferred directly to the driver and occupants. In this respect, two prominent regulations for frontal impact, namely United Nation Economic Commission of Europe (UNECE) Regulation no. 29 and New Car Assessment Program (NCAP) is used to determine whether the structures are having enough strength to withstand the load produced by the impact. This paper deals with the finite element simulation of a frontal impact on bus superstructure by applying both of the regulations. Then, the results for both simulations are compared in terms of energy produced, structure deformations, maximum stress, and the corresponding plastic strains. It is found that the energy from the ECE R29 regulation is lower than NHTSA’s NCAP with 55 kJ and 142 kJ respectively. However, the deformation observed from R29 simulation, the front structures is severely deformed. Meanwhile, the structures in the NCAP simulation are still intact and the steering wheel structures are still not in contact with any body parts of the driver.
Evaluation of ΔJ-integral for a shallow crack in steel for pressure vessels under large scale yielding (LSY) condition
Authors: Muhamad Azmi M S , Fujii Tomoyuki , Tohgo Keiichiro , Hashim M S M , Ismail A H , Razlan Z M 
Published: December 2019

Abstract
Fracture mechanics studies on fatigue crack growth under elastic-plastic condition is usually characterized by J integral range, ΔJ determined by an approximation from area under load-displacement hysteresis loop developed by Dowling and Begley. Despite being supported by some experimental data which reported that fatigue crack growth rates under elastic-plastic conditions have good correlations with ΔJ, the applicability of ΔJ on crack growth in a material subjected to cyclic bending remains inconclusive. In this study, finite element analysis of a four point-bending rectangular plate model with an edge crack length a/W between 0.1 to 0.5 was carried out under displacement amplitude δ

a
between 0.1 to 1.5 mm to represent small to large scale yielding conditions. The elastic component was found to be the driven force of fatigue crack growth parameter in small scale yielding (SSY) condition while in large scale yielding (LSY) condition, the plastic component must be considered. It was also found that the simple method of ΔJ-integral calculation using load-displacement approach is overestimated for shallow crack under LSY condition.
CFD simulations on a phase change thermal energy storage integrated with conducting fins
Authors: Abdul Razak Muhammad Faris , Mohd Amin Nasrul Amri , Abdul Majid Mohd Shukry , Mohd Nasir Nashrul Fazli , Abdul Rahman MD Tasyrif , Rahman Anas Abdul 
Published: December 2019

Abstract
Global warming has become a major problem that leads to an abnormal climate change crisis. For most countries around the world, there be would be a rise in the average daily temperature. Therefore, many research works have been conducted in order to overcome this problem. One of the most viable solutions is to store thermal energy for later use. This can be done by integrating phase change material (PCM) into thermal energy storage (TES) system. To counter the increasing temperature problem in the residential house, PCM can be implanted in the wall of the house, for instance. This way, PCM can go through freezing process during the night and countering the heat through the wall by melting process during day time. However, due to the thermal resistance within these systems, the inadequate heat transfer problem had always become the problem of low thermal conductivity. Therefore, the integration of conducting fins is proposed to the system to increase the overall thermal conductivity.
Orthodontics Anchorage in Mandibular Angle Fractures –A Brief Review
Authors: Abdul Halim Siti Aisyah , Daud Ruslizam , Ibrahim Ishak , Mat Fauziah , Kamaruddin Nur Saifullah , Ismail Rohaizar 
Published: December 2019

Abstract
Maxillofacial fracture could be a quite common injury these days particularly in jaw angle. The healing process is physiologically complicated including each biological and mechanical aspects. Over the past decade, mandibular angle fracture simulation and modeling has been used to understand its details and mechanisms, to analyze specific clinical inquiry and to style healing approches. This paper aims to review the history and also the most recent work on biological and mechanical properties of miniplate . This paper provides a short review of mandibular angle fracture, miniplate evolution, biomaterials utilized in miniplates, structure of miniplates and finite element analysis of miniplate in three dimensional (3D) model.
A short review on the extraction of kenaf fibers and the mechanical properties of kenaf powder composites
Authors: Shahar F S , Sultan M T H , Shah A U M , Safri S N A 
Published: December 2019

Abstract
Kenaf fibers are rapidly growing in the global market and currently being used as a composite to replace other expensive composite materials available in the market. Kenaf powder has the potential to replace other traditional fillers due to its low cost, eco-friendliness, and renewability. The aim of this paper is to review on the mechanical properties of Kenaf fibers, and its powder composites. This paper discusses on the Kenaf plants itself, extraction process, physical properties of kenaf fibers, and finally the mechanical properties of the kenaf powder composites. It can be concluded that Kenaf powder composite has more opportunity for further growth with new methods and technologies which keeps on evolving.
Thermal properties of pineapple leaf/kenaf fibre reinforced vinyl ester hybrid composites
Authors: Mazlan A A , Sultan M T H , Shah A U M , Safri S N A 
Published: December 2019

Abstract
In this modern technology era, the usage of natural fibres has been widely used in various field of applications such as aerospace, maritime, military, automotive as well as structural building. This is due to the reason that they are lightweight, cheap, good sustainability and biodegradable. Only a small amount of research work being conducted on the hybridization of pineapple leaf and kenaf fibres reinforced with vinyl ester (PALF/KF/VE) hybrid composites. Thus, in this present work, the PALF/KF/VE hybrid composites are presented. The thermal properties of PALF, KF, VE as well as hybrid composites were investigated based on their structural components. PALF was in long fibre form while kenaf fibre was in woven form fabricated to form hybrid composites by using the hand lay-up and hot compression moulding. TGA testing was conducted to determine their respective thermal properties. From the experimental testing, the results showed that the thermal stability of hybrid composites enhanced rather than fibres themselves. The thermal degradation of PALF and KF occurred at the range temperature of 250-370°C while neat VE, PALF/VE and PALF/KF/VE occurred at 300-450°C. Thus, these composites can be used for various application such as automotive, aerospace, structural and others.