bluuebunny/crossref_metadata_2025 huggingface dataset:
The optimization of biodiesel production from transesterification of sesame oil via applying ultrasound-assisted techniques: comparison of RSM and ANN–PSO hybrid model
Authors: Soltani Hadi , Karimi Asadollah , Falahatpisheh Sahar
Published: September 2020

Due to the finite source of fossil fuels and their high emissions, it is remarkable to recognize appropriate ways to produce alternative fuels with less pollution. In this paper, the production of biodiesel (fatty acid methyl ester) from transesterification of methanol with sesame oil under ultrasound-assisted waves (using a homogeneous sodium hydroxide catalyst) was investigated. In addition, the optimization and prediction of biodiesel production was studied and compared with the two methods of response surface methodology (RSM) and the combined model of artificial neural network (ANN) – particle swarm algorithm (PSO). The central composite design (CCD) was used to investigate the effect of independent variables (methanol/oil molar ratio, catalyst percentage, reaction time and temperature) on the yield of biodiesel in Expert Design software. Analysis of experimental results was performed using RSM and ANN–PSO hybrid methods and also the optimal conditions for maximizing the yield were calculated. The highest yield of biodiesel predicted by RSM and ANN–PSO were 87.4 and 90.58%, respectively. RSM and ANN–PSO hybrid models were compared based on least squared errors statistically. The correlation coefficients in the RSM and ANN–PSO hybrid models were 0.959 and 0.999 respectively. While both models demonstrated a good agreement with actual results, but the ANN–PSO hybrid model had a powerful prediction for the optimal points over the RSM.
Biochemical unity revisited: microbial central carbon metabolism holds new discoveries, multi-tasking pathways, and redundancies with a reason
Authors: Schada von Borzyskowski Lennart , Bernhardsgrütter Iria , Erb Tobias J.
Published: September 2020

For a long time, our understanding of metabolism has been dominated by the idea of biochemical unity, i.e., that the central reaction sequences in metabolism are universally conserved between all forms of life. However, biochemical research in the last decades has revealed a surprising diversity in the central carbon metabolism of different microorganisms. Here, we will embrace this biochemical diversity and explain how genetic redundancy and functional degeneracy cause the diversity observed in central metabolic pathways, such as glycolysis, autotrophic CO2fixation, and acetyl-CoA assimilation. We conclude that this diversity is not the exception, but rather the standard in microbiology.
Thiol-based switching mechanisms of stress-sensing chaperones
Authors: Ulrich Kathrin , Schwappach Blanche , Jakob Ursula
Published: September 2020

Thiol-based redox switches evolved as efficient post-translational regulatory mechanisms that enable individual proteins to rapidly respond to sudden environmental changes. While some protein functions need to be switched off to save resources and avoid potentially error-prone processes, protective functions become essential and need to be switched on. In this review, we focus on thiol-based activation mechanisms of stress-sensing chaperones. Upon stress exposure, these chaperones convert into high affinity binding platforms for unfolding proteins and protect cells against the accumulation of potentially toxic protein aggregates. Their chaperone activity is independent of ATP, a feature that becomes especially important under oxidative stress conditions, where cellular ATP levels drop and canonical ATP-dependent chaperones no longer operate. Vice versa, reductive inactivation and substrate release require the restoration of ATP levels, which ensures refolding of client proteins by ATP-dependent foldases. We will give an overview over the different strategies that cells evolved to rapidly increase the pool of ATP-independent chaperones upon oxidative stress and provide mechanistic insights into how stress conditions are used to convert abundant cellular proteins into ATP-independent holding chaperones.
Perceived partner humor use and relationship satisfaction in romantic pairs: The mediating role of relational uncertainty
Authors: Miczo Nathan , Averbeck Josh M.
Published: September 2020

This study investigated relational uncertainty as a mechanism through which perceived partner humor use affects recipient’s relationship satisfaction. Two hundred individuals completed measures of their partners’ perceived positive and negative humor use, their relational uncertainty and relationship satisfaction. Results reveal that perceived partner’s positive relational humor use predicted greater relationship satisfaction, and perceived partner’s negative relational humor use predicted diminished relationship satisfaction. Further, relational uncertainty mediated relationships between perceived partner positive humor and satisfaction and perceived partner negative humor and satisfaction.
Quadratic refinements of Young type inequalities
Authors: Ren Yonghui , Li Pengtong , Hong Guoqing
Published: September 2020

In this paper, we mainly give some quadratic refinements of Young type inequalities. Namely:

(
v
a
+
(
1
−
v
)
b

)

2

−
v

∑

j
=
1

N

2

j

(

b
−

a

b

2

j

−
1

2

j

)

2

≤
(

a

v

b

1
−
v

)

2

+

v

2

(
a
−
b

)

2

$$\begin{array}{}
\displaystyle
(va+(1-v)b)^{2}-v{{\sum\limits_{j=1}^N}}2^{j}\Big(b- \sqrt[2^{j}]{ab^{2^{j}-1} }\, \Big)^{2}\leq(a^{v}b^{1-v})^{2}+v^{2}(a-b)^{2}
\end{array}$$

for v ∉ [0,

1

2

N
+
1

$\begin{array}{}
\displaystyle
\frac{1}{2^{N+1}}
\end{array}$

], N ∈ ℕ, a, b > 0; and

(
v
a
+
(
1
−
v
)
b

)

2

−
(
1
−
v
)

∑

j
=
1

N

2

j

(

a
−

a

2

j

−
1

b

2

j

)

2

≤
(

a

v

b

1
−
v

)

2

+
(
1
−
v

)

2

(
a
−
b

)

2

$$\begin{array}{}
\displaystyle
(va+(1-v)b)^{2}-(1-v){{\sum\limits_{j=1}^N}}2^{j}\Big(a- \sqrt[2^{j}]{a^{2^{j}-1}b}\, \Big)^{2}\leq(a^{v}b^{1-v})^{2}+(1-v)^{2}(a-b)^{2}
\end{array}$$

for v ∉ [1 −

1

2

N
+
1

$\begin{array}{}
\displaystyle
\frac{1}{2^{N+1}}
\end{array}$

, 1], N ∈ ℕ, a, b > 0. As an application of these scalars results, we obtain some matrix inequalities for operators and Hilbert-Schmidt norms.
Properties and methods of estimation for a bivariate exponentiated Fréchet distribution
Authors: Saboor Abdus , Bakouch Hassan S. , Moala Fernando A. , Hussain Sheraz
Published: September 2020

In this paper, a bivariate extension of exponentiated Fréchet distribution is introduced, namely a bivariate exponentiated Fréchet (BvEF) distribution whose marginals are univariate exponentiated Fréchet distribution. Several properties of the proposed distribution are discussed, such as the joint survival function, joint probability density function, marginal probability density function, conditional probability density function, moments, marginal and bivariate moment generating functions. Moreover, the proposed distribution is obtained by the Marshall-Olkin survival copula. Estimation of the parameters is investigated by the maximum likelihood with the observed information matrix. In addition to the maximum likelihood estimation method, we consider the Bayesian inference and least square estimation and compare these three methodologies for the BvEF. A simulation study is carried out to compare the performance of the estimators by the presented estimation methods. The proposed bivariate distribution with other related bivariate distributions are fitted to a real-life paired data set. It is shown that, the BvEF distribution has a superior performance among the compared distributions using several tests of goodness–of–fit.
Existence and Hyers-Ulam stability results for a class of fractional order delay differential equations with non-instantaneous impulses
Authors: Luo Danfeng , Luo Zhiguo
Published: September 2020

In this paper, we mainly consider the existence and Hyers-Ulam stability of solutions for a class of fractional differential equations involving time-varying delays and non-instantaneous impulses. By the Krasnoselskii’s fixed point theorem, we present the new constructive existence results for the addressed equation. In addition, we deduce that the equations have Hyers-Ulam stable solutions by utilizing generalized Grönwall’s inequality. Some results in this literature are new and improve some early conclusions.
Doublecortin-Like Is Implicated in Adult Hippocampal Neurogenesis and in Motivational Aspects to Escape from an Aversive Environment in Male Mice
Authors: Saaltink Dirk-Jan , van Zwet Erik W. , Vreugdenhil Erno
Published: September 2020

Doublecortin (DCX)-like (DCL) is a microtubule (MT)-associated protein (MAP) that is highly homologous to DCX and is crucially involved in embryonic neurogenesis. Here, we have investigated thein vivorole of DCL in adult hippocampal neurogenesis by generating transgenic mice producing inducible shRNA molecules that specifically target DCL but no other splice variants produced by the DCLK gene. DCL knock-down (DCL-KD) resulted in a significant increase in the number of proliferating BrdU+ cells in the subgranular zone (SGZ) 1 d after BrdU administration. However, the number of surviving newborn adult NeuN+/BrdU+ neurons are significantly decreased when inspected four weeks after BrdU administration suggesting a blockade of neuronal differentiation after DCL-KD. In line with this, we observed an increase in the number of proliferating cells, but a significant decrease in postmitotic DCX+ cells that are characterized by long dendrites spanning all dentate gyrus layers. Behavioral analysis showed that DCL-KD strongly extended the escape latency of mice on the circular hole board (CHB) but did not affect other aspects of this behavioral task. Together, our results indicate a function for DCL in adult neurogenesis and in the motivation to escape from an aversive environment. In contrast to DCX, its pivotal role in the maturation of postmitotic neuronal progenitor cells (NPCs) marks DCL as a genuine adult neurogenesis indicator in the hippocampus.
Documentary Film, Gender, and Activism in China: A Conversation with Ai Xiaoming
Authors: Zeng Jinyan
Published: September 2020

FQ board member and contributor Chris Berry translates a conversation between the independent female filmmakers Ai Xiaoming and Zeng Jinyan. Although of different generations, Xiaoming and Zeng are both outliers in China's male-dominated film industry. The most prominent women filmmaker among the first generation of independent documentarians, Ai Xiaoming has lived under virtual house arrest since Xi Jinping's rise to power in 2012. Zeng Jinyan came to public attention in 2006, when she documented the disappearance of her husband, civil rights activist Hu Jia, in a protest blog; she later completed a PhD on the work of Ai Xiaoming while in exile in Hong Kong. Both women have recently reentered public life, Ai Xiaoming writing about her experiences of the novel coronavirus lockdown in her hometown of Wuhan and Zeng releasing a new film, Hanjiao yu eryu (Outcry and Whisper), focusing on the special pressures placed on women who dare to speak out in public in China.
Optimisation of Current and Pulse Duration in Electric Discharge Drilling of D2 Steel Using Graphite Electrode
Authors: Deepak D. , Shrinivas Patil , Hemant Ganti , Iasy Ralisa
Published: September 2020

Electric discharge machining (EDM) is one of the viable techniques for machining of D2 steel, in which the material removal occurs by spark erosion. The poor selection of EDM parameters affect the machining quality and productivity. Considering this, the present work investigates the effect of current, charging and discharging time on the material removal rate (MRR) and the surface roughness (Ra) while machining of D2 steel using graphite electrode. The results were analysed using statistical methods to identify the effect of control parameters and to optimise the settings. The study shows that MRR and Ra was significantly influenced by current. At optimum settings, the MRR and the Ra obtained was 38.16 mg/min and 3.39 µm respectively. Morphological analysis of the machined surface show that the size of the globules formed decreased with increase in current.
Sound Transmission Loss Analysis on Building Materials
Authors: Hong Tan Wei , Sin C. F.
Published: September 2020

This study is mainly to determine the sound transmission loss (STL) performance of the four selected building materials using the impedance tube. The four building materials are; autoclaved aerated concrete (AAC), laminated glass, expanded polystyrene and rockwool. Transmission loss occurs when a sound goes through a partition or barrier. The specimens are prepared in two thicknesses, which are 10 mm and 20 mm. The STL of the specimen was determined and analysed. It is observed that the STL results for all the tested materials are having a similar trend, which is a thicker specimen gives higher STL. In general, all the materials deliver high STL at the frequency range of 3000 – 5500 Hz. In overall, the result shows that the expanded polystyrene scores the highest STL among the four building materials in this study. Six combinations of different material also were tested, and AAC & expanded polystyrene combination shows the highest STL value among the six combinations. The outcomes of this study can be referred by noise control engineer on the selection of the sound insulation material for the building noise insulation treatment.
Reliability Estimation of Transport Means Elements Under the Action of Cyclic Loads and Corrosive Environment
Authors: Popovych P. V. , Dzyura Volodymyr , Shevchuk O. S.
Published: September 2020

The approach for determining the residual life of the vehicles’ thin-walled metal elements with cracks under the action of cyclic loads and corrosive environment is developed based on the first law of thermodynamics and the fracture mechanics principles. Based on the results of the mathematical description of electrochemical reactions and separate data of fracture mechanics, the equation describing the kinetics of the corrosion-fatigue cracks propagation is deduced. This equation and the initial and final conditions are a mathematical model for determining the residual life of structural elements. The correctness of the developed analytical models is confirmed by the experimental data known in the literature. The performance of this model is demonstrated on the example of determining the residual life of a plate made of 17G1S steel. The plate was diluted by a crack in a 3% NaCl solution and subjected to cyclic loading. An increase in the initial size of corrosion-fatigue cracks is significant to reduce the period of their subcritical growth.
Non-Newtonian Film Thickness Formation in Ultra-thin Film
Authors: Abd Alsamieh M. F.
Published: September 2020

This paper aims to show the characteristics of ultra-thin films for non-Newtonian fluid using Ree-Eyring model where intermolecular forces of solvation and Van der Waal's are considered in addition to the hydrodynamic action to fulfill an identified need for such a conjunction. In this case, the film thickness and pressure distribution are obtained by simultaneous solution of the modified Reynolds’ equation incorporating the effect of non-Newtonian fluid, film thickness equation including elastic deformation caused by all contributing pressures and the load balance equation using Newton-Raphson method with Gauss-Seidel iterations. Effect of changing the operating conditions of speed, load, Eyring shear stress and slide-roll ratio on the characteristic of the contact has been studied. The results show that, for the case where the hydrodynamic action is the only pressure acting to support the applied load capacity, the film thickness and the pressure gradient at the exit of the contact obtained using non-Newtonian model is different than that formed using the Newtonian model especially for the increased value of slide-roll ratio. The main results of this study are that for ultra-thin film, the film thickness formed using non-Newtonian model is smaller compared to that obtained using Newtonian case and the discretization of the film thickness as the gap is reduced occurs similar to the results obtained using Newtonian model. The pressure shape shows no difference compared to that formed using the Newtonian case in which an oscillation around the Hertizan contact pressure shape due to the solvation effect appears. The results also show that for ultra-thin film, changing the Eyring shear stress does not affect the film thickness formation.
Acoustic Study of an Air Intake System of SI Engine using 1-Dimensional Approach
Authors: Dahlan A. A. , Muhammad Said Mohd Farid , Abdul Latiff Z. , Mohd Perang M. R. , Abu Bakar S. A. , Abdul Jalal R. I.
Published: September 2020

Air intake system of an internal combustion engine plays main role in delivering fresh air from the environment to the engine and dampening the sound of the engine combustion process coming from the engine combustion process. In this study, a simulation was conducted to improve the existing air intake system design in terms of acoustic study to have better sound quality by modifying the resonators, air duct and airbox volume of the air intake module. This study implements the 1-dimensional simulation study using commercial software, correlate to the 1.6-liter natural aspirated engine. The objective of this study is to decrease the engine noise at snorkel of the air intake module without losing too much of pressure drop. At the end of this study, the analysis defines the geometry of air intake module with the recommended resonator for fabrication and physical testing. The simulation result shows that the modified air intake module meet the objective and fulfil the performance target.
EVA Film Reinforced with Acid Functionalized Graphene Nanoplatelets as a Transparent Barrier Layer to Enhance the Durability of Solar Cells
Authors: Yuwawech K. , Wootthikanokkhan J.
Published: September 2020

This research work concerns the development of transparent barrier films based on ethylene vinyl acetate copolymer (EVA) reinforced with the acid functionalized graphene nanoplatelets (GNP). GNP was melt-compounded with EVA in a micro-compounder via two types of mixing schemes. The effect of concentration of GNP on the barrier, thermo-mechanical and optical properties of the EVA composite films were investigated. Water vapour transmission rate of the EVA film decreased by more than 70% after 0.001-0.01 wt% of the GNP was applied. The visible light transmittance in the range of 84-91% was maintained. SEM images showed a random distribution of GNP in the EVA matrix with intimate contact between phases. FTIR spectra imply a polar-polar interaction between the two materials. Tensile toughness of the composite films increased with the concentration of GNP. These demonstrated that the acid functionalized GNP is compatible with EVA. The degree of swelling of the cured EVA films also decreased with the GNP content. The above effects were less obvious when the mixing scheme was changed to the master-batch method. Finally, by applying the EVA/GNP film to encapsulate dye-sensitised solar cells, the lifetime of the device was prolonged by at least three weeks, with the normalised PCE value of 0.74.
Influence of Optimal Tooth Modifications on Dynamic Characteristics of a Vehicle Gearbox
Authors: Ullah Najeeb , Cong T. , Huan B. , Yucheng H.
Published: September 2020

Considering the practical problems of gear noise and vibration, this work focuses on the gearbox of the electric vehicle as the research object to analyse the impact of gear micro-tooth modification. First of all, the effort centres itself on minimising the contact stress and making the load distribution better by implementing the tooth modification on both upper and central speed phases. The procedural analysis of gear tooth modification is executed to make the contact pattern better, so edge contact has been avoided and the load is distributed over a wide area of the tooth for both upper and central gear sets. The contact pattern is positioned in the centre of teeth and contact stress is lowered by 20% to 837 MPA. Then, the peak to peak transmission error is decreased under three proposed modification approaches. Also, contact and bending safety factors are improved as a result of tooth modification. Meanwhile, it was noticed by performing dynamic analysis that right bearings of both upper and central phases have a higher radial response for first two orders which is further decreased to an optimum level as a result of micro-tooth modification strategies.
A Non-Linear Dynamic Model of Ionic Polymer-Metal Composite (IPMC) Cantilever Actuator
Authors: Biswal D. K. , Bandopadhya D. , Dwivedy S. K.
Published: September 2020

This work presents development of an effective non-linear mathematical model for dynamic analysis of Ionic polymer-metal composites (IPMCs) cantilever actuators undergoing large bending deformations under AC excitation voltages. As the IPMC actuator experiences dehydration (solvent loss) in open environment, a model has been proposed to calculate the solvent loss due to applied electric potential following Cobb-Douglas production method. D’Alembert’s principle has been used for the derivation of the governing equation of motion of the system. Generalized Galerkin’s method has been followed to reduce the governing equation to the second-order temporal differential equation of motion. Method of multiple scales has been used to solve the non-linear equation of motion of the system and dehydration effect on the vibration response has been demonstrated numerically.
Capillary Driven Two-Phase Flow Dynamics in Nonpatterned and Patterned Microchannels
Authors: Tahmasebipour M. , Vafaie A.
Published: September 2020

Study of the behavior of fluids inside micro and nanochannels has become particularly important with the extensive advances in micro- and nanofluidic systems. Capillary filling is a phenomenon that occurs in microchannels when the fluid is in contact with the channel walls. This phenomenon can be controlled by introducing certain characteristics in the channel walls and these channels are used in specific applications such as micro-reactors and pressure-sensitive switches. In this paper new insights about some effective parameters in the capillary are provided by which it is possible to increase or decrease the fluid’s velocity or even stop its motion at a specific point in the microchannel. The influence of different regimes governed the capillary action on the fluid’s velocity is studied. Furthermore, the effect of introducing certain obstacles on the microchannel wall on the capillary action and its relation with the contact angle of fluid is investigated. 2D FEM capillary simulation for three different fluids at contact angles of 30, 50 and 60° showed that at 30° and 50° fluid passes the obstacle and at 60° remains pinned at the obstacle. Finally, certain grooves on the channel walls are used to increase fluid’s velocity. Results showed that the grooves increase fluid velocity by 15%.
Comparison of Energy Absorption in Circular Aluminium Crash Boxes with Rigid and Elastic Boundary Conditions: Numerical and Experimental Investigations
Authors: Keshavarzi A. , Marzbanrad J. , Haji Aboutalebi F.
Published: September 2020

Crash boxes are usually used in the transportation and automobile industries. Important parameters such as material, boundary conditions, geometry, impact energy consists of striker mass and velocity, and plastic deformation history can influence on the maximum energy absorption and impact load of these structures. In this research first, crash behaviour of extruded aluminium circular tubes under axial impact loading with rigid and elastic boundary conditions are studied. Then, effect of the elastic support on the tube energy absorption is numerically and experimentally investigated. In the following, the numerical results are compared with the practical observations and validated. Finally, it is revealed that employing the elastic support leads to changing deformation mode and significantly reduces the maximum impact load.
Design and Hydrodynamic Performance of a Horizontal Axis Hydrokinetic Turbine
Authors: Nachtane M. , Tarfaoui M. , El Moumen A. , Saifaoui D. , Benyahia H.
Published: September 2020

Marine energy is gaining more and more interest in recent years and, in comparison to fossil energy, is very attractive due to predictable energy output, renewable and sustainable, the Horizontal Axis Hydrokinetic Turbine (HAHT) is one of the most innovative energy systems that allow transforms the kinetic energy into electricity. This work presents a new series of hydrofoil sections, named here NTSXX20, and was designed to work at different turbine functioning requirement. These hydrofoils have excellent hydrodynamic characteristics at the operating Reynolds number. The design of the turbine has been done utilising XFLR5 code and QBlade which is a Blade-Element Momentum solver with a blade design feature. Tidal current turbine has been able to capture about 50% from TSR range of 5 to 9 with maximum CPower of 51 % at TSR=6,5.   The hydrodynamics performance for the CFD cases was presented and was employed to explain the complete response of the turbine.
Effects of Soda-Lime-Silica Glass and Borax Decahydrate as Alternative Fluxing Agents on the Stoneware Physico-Mechanical Properties
Authors: Natrah S. , Hussin R. , Aramjat A. B.
Published: September 2020

Stoneware especially tableware is manufactured by mixing the clay, quartz and flux such as feldspar. Thus, the aim of this work is to investigate the possibility of two alternative fluxing agents namely; soda-lime-silica glass (SLS), and borax decahydrate (BD) on characterization, and physico-mechanical properties of stoneware to demonstrate its suitability for tableware production. SLS and BD are incorporated into stoneware at the dosage of 5 %, and 10 % by weight, respectively. The sample was performed by uniaxial pressing (40 MPa) sintered at 1000, 1050, 1100, and 1150°C (2 hours soaking time) to establish minimum sintering temperature. Bulk density, water absorption, and modulus of rupture (MOR) were measured for each sample. Characterization of XRF, XRD, and SEM was carried out and discussed. Results indicated SLS, BD showed higher physico-mechanical properties and vitrified at 1050-1100°C, lower than normal temperature applied for stoneware (1150°C). Consequently, it was determined that the usage of SLS and BD as fluxing agent in stoneware is possible.
Investigation of Compressive Stress on Lumbar Spine due to Whole Body Vibration Exposure in Rotary Tillage Operation
Authors: Singh A. , Nawayseh N. , Singh L. P. , Singh S. , Singh H.
Published: September 2020

The aim of this study is to investigate the compressive stress on lumbar spine due to whole body vibration (WBV) exposure in real field rotary soil tillage operation. The spinal stress was evaluated in terms of daily equivalent static compression dose (Sed) with respect to various ride conditions (i.e. forward speed, pulling force and tilling depth). Taguchi's L9 orthogonal array was used to form a systematic set of experiments by varying each ride condition over three levels. Signal-to-noise (S/N) ratios were computed to analyse the holistic effect of ride conditions among all the experimental conditions. In addition, the power spectral density (PSD) of the acceleration at the seat pan was measured along the dominant axis for each experiment. A second order regression model was developed to predict the real experimental Sed response. Further, the ride conditions were optimised by using desirability technique with the aim of minimizing Sed response. The magnitude of daily equivalent static compression dose was found between 0.38 and 0.76 MPa which shows a moderate probability of an adverse health effects as per ISO2631-5: 2004. Statistically, forward speed and pulling force are found to significantly affect the Sed response with a contribution of 64.43% and 24.73%, respectively. The PSD indicated that the vibration energy of the acceleration measured on the seat pan depend on the ride conditions. The predicted response of regression model showed 4.56% error in obtaining the actual experimental values. The optimised forward speed, pulling force and tilling depth levels were found to be 0.6 m/s, 2 kN, and 0.10 m, respectively.
Vibration Transmitted to the Hand by Backpack Blowers
Authors: Alamin Gabasa S. A. , Md Razali Khairil Anas , As’arry Azizan , Abdul Jalil Nawal Aswan
Published: September 2020

Backpack machines such as grasscutter and blower produce a vibration that is transmitted to the operator’s body and hand. Prolonged exposure to vibration can cause injuries known as Hand-Arm Vibration Syndrome. One of the machines used widely in the agriculture sector is the blower. The objective of this study is to evaluate the level of vibration emitted by blowers according to the method in the International Standard ISO 5349. Vibrations emitted by two backpack machines, mist blower and leaf blower, were acquired on ten subjects who were working and using the tools daily. Vibrations were recorded at operational and idle modes using an accelerometer installed in an aluminium palm adapter that was placed between the hand and the surface of the handle. The study has found that the median weighted Wh vibration magnitudes emitted by blowers to the hand were between 1.71 and 2.91 m/s2 r.m.s. acceleration for operational and idle modes, respectively. The mist blower has an idle mode weighted Wh vibration magnitude greater than its operational mode, whilst the leaf blower has an operational mode weighted Wh vibration magnitude greater than in its idle mode. This study suggests that vibrations emitted to the hand from a leaf blower and a mist blower can be greater than the exposure action value set by the European Directive 2002 if used for more than 7 hours (mist blower) or 5 hours (leaf blower) per day. Companies that use both machines should set appropriate actions and regulations to reduce the exposure, especially to workers using the machines daily.
High-Resolution Fibre Bragg Grating (FBG) Pressure Transducer for Low-Pressure Detection
Authors: M. Hafizi Z. , Vorathin E. , M. Aizuddin A. , Lim K. S.
Published: September 2020

Fibre Bragg grating (FBG) pressure sensor has shown great potential in replacing the conventional electrical pressure sensor due to its adaptability to the harsh environment. However, increasing its resolution for low-pressure measurement is still a challenge. In this work, the bonding of FBG to a rubber-based diaphragm pressure transducer was proposed. The proposed pressure transducer had enhanced the sensitivity to 117.7 pm/kPa across the range of 40 kPa, which corresponded to the pressure resolution of 0.008 kPa. Furthermore, the proposed pressure transducer possessed a reference FBG for temperature compensation, where the overall temperature effect was less than 1%.
Walking simulation model of lower limb exoskeleton robot design
Authors: Sapiee M. R. , Marhaban M. H. M. , Miskon M. F. , Ishak A. J.
Published: September 2020

Since 1960s, the development of exoskeleton robots have been advancing in the applications such as load carrying, walking endurance, physical assistance and rehabilitation therapy. Rehabilitation therapy in itself is related to walking ability restoration; especially for the elder people. A survey by The United Nations in 2017 revealed increase trend in the number of ageing population. Due to ageing, it may cause weakened limbs, lower limb injuries or disabilities resulting in walking impairment. Elder people suffering from walking impairment will need to undergo walking therapy to recover walking ability. A walking rehabilitation exoskeleton robot can be used for such patients to undergo the therapy by wearing it on their lower body. A lower limb exoskeleton effectiveness for gait recovery assessment in the design stage is not truly explored yet. This can be done by obtaining the simulation model of the lower limb exoskeleton robot structure from its CAD design. The gait pattern tracking response performance of the exoskeleton design to given inputs can then be observed. The lower limb exoskeleton structure is designed using Autodesk Inventor and then imported into SimMechanics. A block diagram of the exoskeleton model is generated, whereby the model is simulated and its response is observed. Given mathematical expression and experimental data inputs, the exoskeleton model with control system is able to track given joint trajectory inputs. The lower limb exoskeleton model shows that the response of its joints to the inputs can replicate human joints behavior during walking for any given stimulus inputs.
Comparison of the performance of oscillating water column devices based on arrangements of water columns
Authors: Jasron Jahirwan Ut , Soeparmani Sudjito , Yuliati Lilis , Darmadi Djarot B.
Published: September 2020

The hydrodynamic performance of oscillating water column (OWC) depends on the depth of the water, the size of the water column and its arrangement, which affects the oscillation of the water surface in the column. An experimental method was conducted by testing 4 water depths with wave periods of 1-3 s. All data recorded by the sensor is then processed and presented in graphical form. The research focused on analyzing the difference in wave power absorption capabilities of the three geometric types of OWC based on arrangements of water columns. The OWC devices designed as single water column, the double water column in a series arrangement which was perpendicular to the direction of wave propagation, and double water column in which the arrangement of columns was parallel to the direction of wave propagation. This paper discussed several factors affecting the amount of power absorbed by the device. The factors are the ratio of water depth in its relation to wavelength (kh) and the inlet openings ratio (c/h) of the devices. The test results show that if the water depth increases in the range of kh 0.7 to 0.9, then the performance of the double chamber oscillating water column (DCOWC) device is better than the single chamber oscillating water column (SCOWC) device with maximum efficiency for the parallel arrangement 22,4%, series arrangement 20.8% and single column 20.7%. However, when referring to c/h, the maximum energy absorption efficiency for a single column is 27.7%, double column series arrangement is 23.2%, and double column parallel arrangement is 29.5%. Based on the results of the analysis, DCOWC devices in parallel arrangement showed the ability to absorb better wave power in a broader range of wave frequencies. The best wave of power absorption in the three testing models occurred in the wave period T = 1.3 seconds.
The dependency of the microhardnes on microstructure and solidification parameters of directionally solidified Al–4.5wt.%Cu in clay mold
Authors: Masnur Dedy , Malau Viktor , Suyitno Suyitno
Published: September 2020

Improvement of material properties is achieved by controlling parameters involved in the solidification process; therefore, understanding them and their implication are essential. This work investigated the dependency of solidification parameters (cooling rate (TR), growth rate (VL), local solidification time (tSL), temperature gradient (G)), microstructure parameters (primary (λ1) and secondary (λ2) dendrite arm spacing), and micro-hardness values (HV) of Al-4.5wt.%Cu in the clay mold. The samples were directionally solidified in Bridgman vertical apparatus and the temperature is recorded during the cooling. The solidification parameters were obtained from the cooling curve. The microstructures and micro-hardness were characterized using an optical microscope and micro-hardness tester. The microstructure parameters were measured and plotted as functions of solidification parameters using linear regression. The relation between HV and microstructure parameters are analyzed. The results show the λ1 and λ2 change inversely with solidification parameters except for tSL. Comparison to other works shows the exponent values of solidification parameters of the clay mold are lower than that of the carbon and stainless-steel mold. The exponent value of λ2 in the clay mold is -0.183, close to the value in the graphite mold. The clay has the potential as mold material since it characteristic close to the graphite.
Prediction of fatigue life of aluminum 2024-T3 at low temperature by finite element analysis
Authors: Mazlan S. , Yidris N. , Zahari R. , Gires E. , Majid D.L.A. , Ahmad K.A.
Published: September 2020

The change in material properties at low temperature has always been one of the concerned design factors in aircraft industries. The wings and fuselage are repeatedly exposed to sub zero temperature during cruising at high altitude. In this study, fatigue tests were conducted on standard flat specimens of aluminum 2024-T3 at room temperature and at -30 °C. The monotonic and cyclic loading tests were conducted using MTS 810 servo hydraulic machine equipped with a cooling chamber. The monotonic tests were conducted at a crosshead speed rate of 1 mm/min and the cyclic tests at a frequency of 10 Hz with a load ratio of 0.1. The experimental data obtained, such as the yield strength, ultimate strength and S-N curve were used as the input parameters in ANSYS Workbench 16.1. This close agreement demonstrates that the isotropic model in ANSYS workbench is essential in predicting fatigue life. The increase in stress parameter causes fatigue life to decrease. Besides, the decrease in temperature causes the total fatigue life to increase.
A comparative study on the vibration of functionally graded Magneto-Electro-Elastic rectangular plate rested on a Pasternak foundation based on exponential and first-order shear deformation theories
Authors: Talebi Amanieh Hamidreza , Seyed Roknizadeh Seyed Alireza , Reza Arash
Published: September 2020

In this paper, the in-plane and out-of-plane free vibrations of the functionally graded magneto-electro-elastic (FG-MEE) rectangular plate on a pasternak foundation were evaluated based on exponential shear deformation theory (ESDT) and first order shear deformation theory (FSDT). The material properties of FG-MEE varied along the thickness according to a power-law distribution model. It was assumed that the FG-MEE plate is subjected to initial external electrical and magnetic potentials; mreover, simply-supported boundary conditions were considered for all the edges of the FG-MEE plate. Firstly, the corresponding partial differential equations (PDEs) were derived using Hamilton’s principle, then, the natural frequencies were determined by solving the obtained equations through Navier’s approach according to the assumed boundary conditions. The results revealed that the natural frequencies of the plate decrease/increase with the increase of the electric/magnetic potentials. Moreover, the results showed a 0.03%, difference between the natural frequencies of the plate with a thickness-to-length ratio of 0.1 based on FSDT and ESDT; when the aspect ratio was increased to 0.2 and 0.3 this difference rose to 0.2% and 0.5%, respectively.
Factors That Influence Capital Structure With Profitability as A Moderating Variable
Authors: Wardani Oktavia Mulyatika , Subowo Subowo
Published: September 2020

This study aims to determine the effect of business risk, Fixed Asset Ratio (FAR), and Time Interest Earned (TIE) on capital structure with profitability as a moderating variable. The main theories in this research are trade-off theory and signal theory. The population in this study were 155 manufacturing companies listed on the Indonesia Stock Exchange in 2015-2017. The sample selection used a purposive sampling technique and selected 90 companies with 235 units of analysis. The analysis techniques used descriptive statistical analysis, inferential analysis, and moderated regression analysis (MRA) which processed through IBM SPSS 23. The results show that business risk and time interest earned have a significant negative effect on the capital structure while fixed asset ratio has a significant positive effect on capital structure. Profitability is able to moderate the effect of fixed asset ratios on the capital structure but is not able to moderate the influence of business risk and time interest earned on capital structure. The conclusion of the study is that business risk has a negative effect significant to the capital structure and fixed asset ratio has significant positive effects on capital structure. This can be used as the basis that companies must be careful when raising external funds because it can affect the efficiency and profitability of the company.
The Effect of Tax Minimization and Exchange Rate on Transfer Pricing Decisions with Leverage as Moderating
Authors: Devi Diah Kumala , Suryarini Trisni
Published: September 2020

The aims of this research are to analyze and to find empirical evidence about the effect of tax minimization and exchange rate on company decision of transfer pricing with leverage as moderating variable. The population of this research was mining companies which listed in Indonesia Stock Exchange (IDX) over the period 2013 to 2018 from 45 companies. The sampling technique used purposive sampling. Eighteen companies were selected with 65 units analysis were obtained. In addition, data was analyzed using descriptive statistics and inferential statistics using Moderated Regression Analysis (MRA). The data was processed by IBM SPSS Statistics 21 software. The results show that tax minimization and exchange rate have positive and significant effect on transfer pricing. Leverage does not moderate the effect of tax minimization on transfer pricing but leverage significantly moderate the effect of exchange rate on transfer pricing. The conclusion of this research is transfer pricing decision will be higher when tax minimization and exchange rate be higher, but leverage can moderate the effect of exchange rate to transfer pricing.
Analyze Factors That Affect Carbon Emission Disclosure (Case Study in Non-Financial Firms Listed on Indonesia Stock Exchange in 2014-2016)
Authors: Hapsari Cantika Anindya , Prasetyo Andrian Budi
Published: September 2020

The objective of this study is to find out what factors that can have an impact on carbon emissions disclosure in non-financial companies listed on the Indonesia Stock Exchange that publish sustainability reports for the year 2014-2016. The variables that would be tested in this study are independent variables consisting of industry type, company size, profitability, leverage and corporate governance, as well as the dependent variable which is the carbon emissions disclosure. Based on secondary data and purposive sampling methods, a total of 57 companies were obtained as research samples. Multiple linear regression is used as a model analysis of this study. Based on the test results, it has been found that the variables that have a significant influence on the level of carbon emissions disclosure are industry type, company size and leverage, while the remaining variables were found to have no significant effect.
Evolutionary Dynamics of Transposable Elements Following a Shared Polyploidization Event in the Tribe Andropogoneae
Authors: Ramachandran Dhanushya , McKain Michael R , Kellogg Elizabeth A , Hawkins Jennifer S
Published: September 2020

Both polyploidization and transposable element (TE) activity are known to be major drivers of plant genome evolution. Here, we utilize the Zea-Tripsacum clade to investigate TE activity and accumulation after a shared polyploidization event. Comparisons of TE evolutionary dynamics in various Zea and Tripsacum species, in addition to two closely related diploid species, Urelytrum digitatum and Sorghum bicolor, revealed variation in repeat content among all taxa included in the study. The repeat composition of Urelytrum is more similar to that of Zea and Tripsacum compared to Sorghum, despite the similarity in genome size with the latter. Although LTR-retrotransposons were abundant in all species, we observed an expansion of the copia superfamily, specifically in Z. mays and T. dactyloides, species that have adapted to more temperate environments. Additional analyses of the genomic distribution of these retroelements provided evidence of biased insertions near genes involved in various biological processes including plant development, defense, and macromolecule biosynthesis. Specifically, copia insertions in Zea and T. dactyloides were significantly enriched near genes involved in abiotic stress response, suggesting independent evolution post Zea-Tripsacum divergence. The lack of copia insertions near the orthologous genes in S. bicolor suggests that duplicate gene copies generated during polyploidization may offer novel neutral sites for TEs to insert, thereby providing an avenue for subfunctionalization via TE insertional mutagenesis.
META ANALISIS PEMENUHAN HAK ASIMILASI NARAPIDANA
Authors: EFRILIAWATI TRIE
Published: September 2020

Abstract. From the research that has been conducted by the cadets of Akademi Ilmu Pemasyarakatan (AKIP) for ten years from 2007 to 2017, the authors found that the problems in implementing assimilation in prisons tend not to change. Whereas the regulations on assimilation have been amended twice in the last ten years. The theory that I use in this research is organizational theory. Through the theory, the author wants to link the reintegration of prisoners as the goal of the correctional system with policies governing the fulfillment of prisoners' assimilation rights. From the many problems faced by prisons in fulfilling the assimilation rights of prisoners, it can be concluded that these problems basically arise from three aspects: 1) organization, 2) human resources, and 3) society. Prisons will continue to face these problems as in the past ten years if the Government does not immediately take the right policy. Abstrak. Dari penelitian yang telah dilakukan oleh taruna Akademi Ilmu Pemasyarakatan (AKIP) selama sepuluh tahun sejak 2007 hingga 2017, penulis menemukan bahwa permasalahan dalam pelaksanaan asimilasi di lapas cenderung tidak berubah. Padahal peraturan tentang pemberian asimilasi itu sudah diubah sebanyak dua kali dalam sepuluh tahun terakhir. Teori yang penulis gunakan dalam penelitian ini ialah teori organisasi. Melalui teori ini, penulis ingin mengaitkan reintegrasi narapidana sebagai tujuan sistem pemasyarakatan dengan kebijakan yang mengatur tentang pelaksanaan pemenuhan hak asimilasi narapidana. Dari sekian banyak permasalahan yang dihadapi lapas dalam melaksanakan pemenuhan hak asimilasi narapidana, dapat disimpulkan bahwa masalah-masalah tersebut pada dasarnya timbul dari tiga aspek yaitu 1) organisasi, 2) sumber daya manusia, dan 3) masyarakat. Adapun masalah-masalah ini akan terus dihadapi lapas seperti sepuluh tahun belakangan jika Pemerintah tidak segera mengambil kebijakan yang tepat.
Modeling of acoustic fields during gas flow around bodies
Authors: Bagapov Arif R. , Zhalnin Ruslan V.
Published: September 2020

The article describes the modeling of the acoustic field based on the analysis of pressure fluctuations. For this a model based on the laws of mass, energy and momentum is implemented in a two-dimensional setting. For the calculations, the HLLC scheme for solving the Rieman problem and the WENO scheme for reconstructing the gas-dynamic parameters on the faces between the cells are used. To simulate the acoustic field, a time-averaged characteristic was chosen - the overall sound pressure level (OASPL). The paper considers the acoustic field obtained when a gas flows around a single square body, a cascade of square bodies, a step and a cavity, an interpretation of the ongoing processes is given. The result of the study is the visualization and description of the phenomena that arise when a gas flow around bodies, as well as the study of the effect of removing the observation point on acoustic effects within the simulated area.