bluuebunny/crossref_metadata_2025 huggingface dataset:
VISCOELASTIC ADHESION OF A SPHERICAL TIP INDENTING A FLAT RIGID SURFACE USING LENNARD-JONES INTERACTION
Authors: Leong A.K.X. , Chong W.W.F.
Published: October 2019

Solid and elastic contact problems have been thoroughly investigated before. The most recent efforts incorporate the use of the Lennard-Jones (LJ) potential to describe the inter-surface forces that are present and substantial in micro-sized contact problems. But little work has been done on viscoelastic contact problems. Hence, there is a need to investigate the behaviour of a viscoelastic contact under the LJ interaction. This paper aims to investigate the deformation of an axisymmetric viscoelastic tip that is either pushed onto or pulled from a flat rigid surface. From existing elastic models, a mathematical model was developed to describe the contact problem in a viscoelastic context. This newly developed was solved via numerical means. The result is a model that readily accepts measureable physical properties and gives out the deformation of a viscoelastic tip.
BIOMECHANICAL BEHAVIOUR OF BOVINE SKIN: AN EXPERIMENT-THEORY INTEGRATION AND FINITE ELEMENT SIMULATION
Authors: Adull Manan Nor Fazli , Mahmud Jamaluddin , Jumahat Aidah
Published: October 2019

This paper for the first time attempts to establish the biomechanical characteristics of bovine skin via experiment-theory integration and finite element simulation. 30 specimens prepared from fresh slaughtered bovine were uniaxially stretched in-vitro using tensile tests machine. The experimental raw data are then input into a Matlab programme, which quantified the hyperelastic parameters based on Ogden constitutive equation. It is found that the Ogden coefficient and exponent for bovine skin are μ = 0.017 MPa and α = 11.049 respectively. For comparison of results, the quantified Ogden parameters are then input into a simple but robust finite element model, which is developed to replicate the experimental setup and simulate the deformation of the bovine skin. Results from experiment-theory integration and finite element simulation are compared. It is found that the stress-stretch curves are close to one another. The results and finding prove that the current study is significant and has contributed to knowledge enhancement about the deformation behaviour of bovine skin.
PRE-CONCENTRATION AND DETERMINATION OF PB(II) FROM WATER SAMPLES USING MODIFIED MULTIWALLED CARBON NANOTUBES
Authors: Pourmand Neda , Sanagi Mohd Marsin , Wan Ibrahim Wan Aini , Salisu Ahmed
Published: October 2019

Pb(II) is a topically poisonous metal ion that can affect almost every organ and system in the body; it can accumulate in the body and cause kidney malfunctioning, hematological and brain damages. Recently, carbon nanotubes (CNTs), the nano-structured material, are applied for pre-concentration of heavy metal ions. This study investigates the pre-concentration of lead ion using oxidized multiwalled carbon nanotubes (MWCNT-COOH) via solid phase extraction method. MWCNT-COOH was prepared using as-synthesized MWCNT and the products were characterized by FTIR, FESEM, TEM and TGA. Various factors influencing the separation and pre-concentration were investigated namely the effects of pH (2-7) and the elution conditions (type, concentration and volume of eluent). The best extraction conditions were sample of pH 5 and 5 mL of 1M HNO3 as eluent. The developed method was successfully applied to the determination of trace quantities of Pb(II) in water samples with good analyte recoveries (90-102.5%).
THE EFFECT OF THE INFLUX OF FOREIGN LABOUR IN MALAYSIA BY AUGMENTED MRW MODEL
Authors: Ahmad Nizam Saiyidatul Saadah , Ahmad Rohanin , Aziz Nur Arina Bazilah
Published: October 2019

There are pros and cons in hiring foreign labour on the economy. The influx of foreign labour is a common phenomenon, but when their involvement is unlimited it will be one serious issue. Malaysia is one of the developing countries where industrial and construction sectors are in need of labour and this has opened up opportunities for foreign labour. Their inflow into Malaysia is increasing every year and this has caused problems such as time-consuming construction due to low-skilled labour and crime problems caused by problematic labour. We augmented Mankiw-Romer-Weil model by isolating the foreign labour element in human capital to find the effect of the influx of foreign labour in Malaysian economic growth. The results from our model show that the employment of foreign labour increases the rate of human capital but decreases the rate of physical capital. Therefore, the level of the production function also decreases.
SUPPLY CHAIN TECHNOLOGY UTILIZATION IN MALAYSIA CONSTRUCTION INDUSTRY
Authors: M. Udin Zulkifli , Othman Abdul Aziz , Ahmad Azhar
Published: October 2019

Supply Chain Technology (SCT) utilization becomes a phenomenon in the construction industry nowadays. The uses of these technologies have shown an improvement in construction business process particularly in planning and designing processes. These improvements significantly affect the performance of Supply Chain Management (SCM) in construction industry. The construction industry is critical for national wealth creation particularly in the developing countries such Malaysia. However, about five percent of construction projects were not able to be completed due to various reasons. Therefore, there is a great interest to find out the level of utilization of SCT within the construction industry, which is believed as a main driver to improve the SCM performance and directly reflect to the construction project performance. The objective of this paper is to identify and highlight the issues and problems associated with the current SCM practices, particularly in the technology utilization among the major players in the Malaysian construction industry.  To be more specifically, the type of application system that is being utilized in the Malaysian construction supply chain process will be identified.
IMPAK PERISIAN IM-SMARTSAFETY TERHADAP PEKERJA ASING DALAM INDUSTRI PEMBINAAN
Authors: Salleh Nurul Azita , Mohd Nawi Mohd Nasrun , Mohd Nordin Norazah , Abdul Rashid Abdul Khalim
Published: October 2019

This paper focuses on the discussion of the impact of IM-SmartSAFETY courseware on foreign workers in the construction industry. This courseware was developed as an alternative media of information delivery in bilingual multimedia and two directional teaching aids for foreign workers in Health and Safety Induction Course (HSIC). The study discovered that the IM-SmartSAFETY courseware have contributed a great impact and meets the needs of the foreign workers on construction sites as well as one of the mechanism to help tackle the language problem. The study was conducted quantitative research methods supported by qualitative research is found a parallel in terms of data acquisition which is seen IM-SmartSAFETY courseware has helped meet the needs of foreign workers regarding personal protective equipment (PPE) in terms of knowledge about the types and uses of PPE, safety regulations related to PPE, proper wear of PPE and the effect of the proper usage of PPE which include safety helmets, safety boots, protective clothing or safety jackets, ear protection, eye and face protection, safety belts, protective glove and protective breathing after using the courseware. The findings also exhibits that the overall of helpfulness of courseware also found that language issues have been resolved. In fact, the acquisition of knowledge foreign workers on safety at construction sites and the way of delivery information by the trainers to foreign workers have been enhanced while reducing the rate of accidents on construction sites and increase foreign workers awareness about the hazard and improve occupational safety of foreign workers in Malaysia.
DIELECTRIC MEASUREMENTS FOR LOW-LOSS MATERIALS USING TRANSMISSION PHASE-SHIFT METHOD
Authors: You K. Y. , Lee Y. S. , Zahid L. , Malek M. F. A. , Lee K. Y. , Cheng E. M. , Khamis N. H. H.
Published: October 2019

This paper presents a calculation of the dielectric properties of low-loss materials using the transmission phase-shift method. This method can provide calibration-independent and position-insensitive features, and it was verified experimentally by measuring several well-known samples using X-band rectangular waveguides.
A STUDY ON THE ESTABLISHMENT AND IMPLEMENTATION OF CONSERVATION PROGRAM IN ARUN LNG PLANT
Authors: Mahidin Mahidin , Hamdani Hamdani , Ibrahim Jailani , Zubir Teuku , Nur Yasin Agus
Published: October 2019

Energy conservation is an important issue in all sectoral activities, especially in processing industries such as natural gas refinery and liquefaction plant, petrochemical and cement mill in which energy isused in large amount. This paper presents a discussion on the experience in establishment and implementation the energy conservation program, including the reduction of greenhouse gas (GHG) emission achieved in the last four years in Arun LNG Plant, a commercial natural gas liquefaction plant in Aceh, Indonesia with a capacity of 2.2 million ton LNG per year. In addition, an analysis on the specific energy consumption and CO2 reduction is provided. The Energy Management Matrix was adopted in assessment of the energy management implementation in theArun LNG Plant. It was found that the efficiency of the plant tended to decrease from year to year, which was represented by the specificity of fuel consumption (accounted based on the LNG product). In 2010 the specific fuel consumption was 0.0088 mmscf per m3 LNG product; it was up to 0.0234 in 2013. Fortunately, it was observed that the specific CO2 reduction (calculated on the LNG product basis) increased during tlast four years; in 2010 and 2013 the specific CO2 reduction was 0.195 and 0.518 ton per 105 m3 LNG produced, respectively.
DFAM: A DISTRIBUTED FEEDBACK ANALYSIS MECHANISM FOR KNOWLEDGE BASED EDUCATIONAL BIG DATA
Authors: F. Olanrewaju Rashidah , Ul Islam Khan Burhan , Naaz Mir Roohie , Mehraj Baba Asifa , Anwar Farhat
Published: October 2019

There is almost digitization of the entire educational system, as there is an abundant of digital materials available. The educational system is not left out from the global standardization as well as authorities are imposing certain standard at local and global level. As a result, these data which are getting generated in the context of educational also complies all the basic characteristics of the Big Data such as volume in terms of size, and others velocity, variety etc. In order to store, search and process an open source project, Apache Hadoop has been conceptualized, whereas it lags the application specific needs especially in the field of education to enhance the teaching and learning processes. In this paper, an architectural model is illustrated to demonstrate the existing eco-system and a proposed model for provisioning the enhanced teaching -learning mechanism, so that it can be adopted to enhance the intelligence into mechanism of educational framework.
EFFECTS OF DIFFERENT TYPE OF COVARIATES AND SAMPLE SIZE ON PARAMETER ESTIMATION FOR MULTINOMIAL LOGISTIC REGRESSION MODEL
Authors: Abdul Hamid Hamzah , Bee Wah Yap , Xie Xian-Jin
Published: October 2019

The sample size and distributions of covariate may affect many statistical modeling techniques. This paper investigates the effects of sample size and data distribution on parameter estimates for multinomial logistic regression. A simulation study was conducted for different distributions (symmetric normal, positively skewed, negatively skewed) for the continuous covariates. In addition, we simulate categorical covariates to investigate their effects on parameter estimation for the multinomial logistic regression model. The simulation results show that the effect of skewed and categorical covariate reduces as sample size increases. The parameter estimates for normal distribution covariate apparently are less affected by sample size. For multinomial logistic regression model with a single covariate study, a sample size of at least 300 is required to obtain unbiased estimates when the covariate is positively skewed or is a categorical covariate. A much larger sample size is required when covariates are negatively skewed.
MAGNETO-CONVECTIVE INSTABILITY IN A HORIZONTAL VISCOELASTIC NANOFLUID SATURATED POROUS LAYER
Authors: Mat Tahir Norazuwin Najihah , Ishak Fuziyah , Awang Kechil Seripah
Published: October 2019

Nanofluids have been shown experimentally to have high thermal conductivity. In this study, the convective instabilities in a horizontal viscoelastic nanofluid saturated by porous layer under the influences of gravity and magnetic field are investigated. The linear stability theory is used for the transformation of the partial differential equations to system of ordinary differential equations through infinitesimal perturbations, scaling, linearization and method of normal modes with two-dimensional periodic waves. The system is solved analytically for the closed form solution of the thermal Darcy-Rayleigh number by using the Galerkin-type weighted residuals method to investigate the onset of both stationary and oscillatory convection. The effects of the scaled stress relaxation parameter, scaled strain retardation parameter and Chandrasekhar number on the stability of the system are investigated. The scaled strain retardation parameter stabilizes while the scaled stress relaxation parameter destabilizes the nanofluid system. The system in the presence of magnetic field is more stable than the system in the absence of magnetic field.
DISCOUNT PRICING STRATEGIES FOR SMART PHONE USING SYSTEM DYNAMICS MODELLING
Authors: Mat Zaib Nurul Afiqah , Bazin Nor Erne Nazira , Mustaffa Noorfa Haszlinna
Published: October 2019

Nowadays, retailers of highly demanded products such as fashion goods and high technology electronic devices (smart phone) are aggressively competing with one another in order to increase revenue and to maintain their position in the market place. Rapid introduction of new smart phone into the market has resulted in shorter product life cycle and intensified competition, which force retailers to enhance their strategic management and creates competitive advantages. The challenge is in designing a suitable pricing strategy and discount offerings. Thus, the aim of this research is to develop a dynamic model to understand the relations between factors influencing the discount-pricing decision, to analyze performance of the discount-pricing strategy and to present an insight on the effects of the strategy implemented. Hence, to help achieve all the purposes, system dynamics approach is chosen to model the discount-pricing strategy for new smart phone. System dynamics modelling simulates the behavior of complex systems over time. Data used in the research is collected from literature review and email interview. The email interview focuses on the information of discount-pricing strategy normally used by retailers. The simulation results show that the value of cumulative sales within introduction phase is the highest as compared to other phases. Based on the survey, it is proposed that suitable discount level to be offered for new smart phone ranges from 10% to 30%. Furthermore, the study suggests that retailers can start a discount promotion early of the month of new smart phone released and, in addition, the discount-pricing strategy model of new smart phone is also produced as one of contribution of this study.
ELECTROCHEMICAL PERFORMANCE OF ORDERED MESOPOROUS CARBON MODIFIED BY OXIDATIVE TREATMENT WITH AQUEOUS NITRIC ACID
Authors: Razman Nur Izzatie Hannah , Endud Salasiah , Misnon Izan Izwan , Ramli Zainab
Published: October 2019

In this study, ordered mesoporous carbon (OMC) was prepared via nano-casting method by using Santa Barbara Amorphous (SBA)-15 as a template and sucrose as a carbon precursor. The OMC was subsequently oxidized with aqueous nitric acid and referred as MOMC. The physicochemical properties of OMC and MOMC were determined using nitrogen adsorption–desorption analyser, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). The results proved that the carbon replication process was successful. The electrochemical performance tests were carried out using cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) in 1 M KOH electrolyte for 1000 cycles. After oxidative treatment, the specific surface area and pore volume of OMC decreased but the specific capacitance of the electrode material has significantly increased from 117      F g–1 to 344 F g–1 at a scan rate of 10 mV s–1.
SV-WAVE WITH EXTERNAL FORCE IN SATURATED MEDIUM
Authors: Lie Siang Teng , Abdul Aziz Zainal , Chuan Ching Dennis Ling
Published: October 2019

There are past researches done for SV-wave with the absence of external force. This work aims to investigate the influence of external force in the propagation of SV-wave in the soluble and insoluble mediums. Isotropic wave model is derived for SV-wave with various forces in accordance to Duhamel Principle and their analytical solutions are used to compare with each other’s’ amplitudes. With the existence of high density fluid, diffusive waves with larger external force will induce higher amplitude. However, SV-waves are non-diffusive in low density medium and hence, this work concludes that wave diffusion by external force is subjected to the properties of the targeted medium
APPLICATION OF MEAN AND STANDARD DEVIATION IN QUESTIONNAIRE SURVEYS: CONSTRUCT VALIDATION
Authors: Sin Yin Teh , Othman Abdul Rahman , Sulaiman Shukri , Mohamed-Ibrahim Mohamed Ismail , Razha-Rashid Mohd
Published: October 2019

A simple method using the descriptive statistics involving mean and standard deviation can be applied in questionnaire surveys. By focusing on the reliability and validity assessment, items should have roughly equivalent means and standard deviations within a Likert scale with the rule of thumb of 2:1 (ratio of the maximum standard deviation to the minimum standard deviation). A comprehensive study on the reliability and validity of the questionnaire to assess computer and internet usages is presented to illustrate how to perform a simple evaluation of the item-level descriptive statistics (mean, standard deviation and frequency), the multitrait/multi-item correlation matrix (Pearson correlation and Biserial correlation) and reliability coefficients and inter-scale correlations (Cronbrach’s alpha and Hoyt’s method). This method is thus applicable in any research that employs a questionnaire.
GAUGING PERFORMANCE OF A QUEUING SYSTEM USING MULTI-SERVER WAITING LINE MODEL (M/M/S): AN INVESTIGATION ON A LOCAL HOSPITAL’S OUTPATIENT DEPARTMENT
Authors: Lamsali Hendrik , Salleh Mohamed Najib
Published: October 2019

Healthcare is a fast growing industry demanding perfection, top notch services and optimal utilization of available resources. Despite shortages in doctors and nurses as well as frequent overcrowding, the number of incoming patients to the government hospitals is increasing every year. The outpatient department in Malaysian Government hospitals is consistently experiencing frequent congestion particularly in the morning. The challenge for hospital administrators is to rightly and timely allocate resources in relevant departments. Henceforth, this study aims to further gauge the performance of an outpatient department in a local hospital in Kedah. In particular, it aims to investigate the current efficiency level of a queuing system of the said department and to propose potential solutions. The study uses Multi-server Queuing Models (M/M/s) to measure the performance of the waiting line. A computational work is then presented to value the operating characteristics of the model. The findings exhibit the performance of existing queuing system and the need to re-examine the number of doctors on duty. In all, the study may be beneficial as a decision making aid to the administrator of the outpatient department particularly to re-look and improve existing queuing system in tandem with the center’s commitment for better customer satisfaction and minimal patients’ turnover.
STUDY OF SPECIFIC PHARMACOLOGICAL ACTIVITY OF SODIUM SALT (4-О-Β-GLUCOPYRANOSYLOXY)-BENZOIC ACID
Authors: Ivan Smirnov , Tatyana Murashko , Alex Ivanov , Alex Bondarev , Vladimir Udut
Published: October 2019

Chronic inflammatory diseases of various genesis are prevalent today. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat pain and inflammation, but their long-term use is associated with complications in the gastrointestinal tract, including peptic ulcers. We synthesized a molecule of sodium salt (4-О-β-glucopyranosyloxy)-benzoic acid. This substance has diuretic and anti-inflammatory activities. It should be noted that most of NSAIDs has analgesic effect. In this connection, the aim of this study was to evaluate the analgesic activity of sodium salt (4-О-β-glucopyranosyloxy)-benzoic acid. We studied analgesic effect in the test “acetic writhing”. Sodium salt (4-О-β-glucopyranosyloxy)-benzoic acid significantly reduces the number of writhing by 14 units during the experiment, as an alternative criterion percent of animals with analgesia was 42.6%. Thus, in the test "acetic writhing" revealed the presence of the analgesic activity have developed drug average severity.
THE EVOLUTION OF RESEARCH AND DEVELOPMENT ON COCHLEAR BIOMODEL
Authors: Ngelayang Thailis Bounya , Yin Fen Low , Latif Rhonira , Yeop Majlis Burhanuddin
Published: October 2019

The research and development of the cochlear biomodels have initially started over a century ago. Since then, various types of approach have been implemented in trials to perfectly replicate the nature of the human auditory system. The evolution started with the implementation of mechanical elements into the cochlear biomodel operating in air and fluidic surrounding. However, due to the huge size of the mechanical cochlear biomodel, the microelectromechanical systems (MEMS) has been implemented in order to attain a life-sized cochlear biomodel. Researchers have looked into the possibilities of fabricating the MEMS cochlear biomodel in air and fluidic mediums. In this paper, the mechanical and MEMS cochlear biomodel implementations will be reviewed. The key part in modelling the cochlea for human auditory system is to mimic closely its nature and capabilities in terms of the geometrical design, material properties and sensory performance.
AUTOMATED DEFORM DETECTION ON AUTOMOTIVE BODY PANELS USING GRADIENT FILTERING AND FUZZY C-MEAN SEGMENTATION
Authors: Edris M. Z. B. , Zakaria Z. , Zin M. S. I. M. , Jawad M. S.
Published: October 2019

Automatic deform detection on automotive body panel is challenging owing to its localization on a large surface, variation in appearance, and their rare occurrences. It is difficult to detect these deforms either by original models or by small-sample statistics using a single threshold. As a consequence, this problem is focussed to derive a lot of good-quality deform detected from the surface images. These detections should discriminate the various surface deforms when fed to suitable image processing algorithms. This paper used gradient filtering and background illumination correction to identify the deform area. An algorithm to segment the deform area has been developed. It segments the deformation by using Fuzzy C-Means (FCM) segmentation. The algorithm is being test on three samples which are car door model, curve and flat surface with two types of deformations which is ding and dent deformations that occur on the surface.
ASSESSMENT OF NATURAL RADIONUCLIDES LEVELS IN DRINKING WATER FROM OGUN STATE, NIGERIA
Authors: M. R. Usikalu , C. O. Olawole , E. S. Joel
Published: October 2019

Naturally occurring radionuclides levels of 238U, 232Th and 40K were investigated in the water samples collected at different boreholes in all the local government of Ogun State using high-purity germanium (HPGe) detector (Canberra Industries Inc.). The activity concentrations measured from the water samples ranged from 0.06 to 1.37 Bq l-1 for 238U, 0.15 to 0.52 Bq l-1 for 232Th and 1.35 to 12.74 Bq l-1 for 40K. The measured activities concentrations for 238U, 232Th and 40K along with their ingested dose conversion factors were used to estimate the annual effective doses in accordance with International Commission on Radiological Protection (ICRP) based on age groups 0 -1y, 1 – 2y, 2 – 7y, 7 – 12y, 12 – 17y and >17y for water consumption. The total annual effective doses calculated varied from 0.004 to 0.517, 0.002 to 0.092, 0.001 to 0.078, 0.001 to 0.076, 0.024 to 0.110 and 0.002 to 0.117 for the age groups accordingly. The physiochemical results showed that 85% of the water was acidic as they have pH less than 6.5 and 65 % of them exceeded the copper concentration recommended limit. It revealed that consumption of the water is safe from natural background radiation for all groups except 0-1 y as the annual effective dose obtained for this group exceeded the average world limit (0.12). The study therefore, suggests that Ogun State populace should use less of these water samples for babies between the age 0-1 year.
EFFECTS OF GYNURA PROCUMBENS EXTRACT ON LIVER FUNCTION TEST OF HYPERCHOLESTEROLEMIA INDUCED RABBITS
Authors: Ismail Mohd Azrul Hisham , Anuar Bahari Ebby , Ibrahim Farrah Shafeera , Dasiman Razif , Amom Zulkhairi
Published: October 2019

Antioxidant works against oxidant and free radicals is by donating electrons it encompasses to the radical molecules and therefore neutralising the oxidation process in the biological system. Hypercholesterolemia has been identified as one the primary predisposing factor for chronic health diseases in most industrial and developed countries.Hypercholesterolemia contributes to nonalcoholic fatty liver diseases (NAFLD). Gynura procumbens is not toxic and exhibit anti-diabetic, anti-inflammatory, anti-hypertensive and wound healing properties where the extract of this plant contains active chemical constituents such as tannins, terpenoids, sterol glycoside, saponins and flavonoids. New Zealand White Rabbits were fed with high cholesterol diet for ten weeks. Liver weight and serum liver function test (LFT) including ALP, ALT, AST and GGT were determined and analyzed. Rabbits that were given high cholesterol diet show the symptom of liver injury. ALP, ALT, AST and GGT levels indicate the liver injury. Liver injury of rabbits that were supplemented with Gynura procumbens extracts were reduced compared to rabbits that were given high cholesterol diet but not given any supplement of extract.  ALP, ALT, AST and GGT level on rabbits were given the extract were improved compared to HCD.  Supplementation of the extract lowered the levels of liver enzymes compared to the HCD.
EEG ELECTRODE LOCALIZATION FOR READING-WRITING NEUROPATHWAY: SPECTRAL ANALYSIS APPROACH
Authors: Mohamad N. B. , Y. Lee Khuan , Mansor W. , Che Wan Fadzal C. W. N. F.
Published: October 2019

Writing is a survival skill in schools and many children are reported to have suffered from writing disorder. Emerging technology enables this disorder detectable through monitoring of EEG signals. However, in working with EEG, the lack of methodological approach would lead to gargantuan of data and thus wastage in resources and time. Furthermore, placing of a large number of electrodes on the recording cap will cause discomfort to the subject, with data being more liable to false readings and artifacts. Recognizing the number of electrodes through proper localization plays a fundamental role in improving the overall performance of an EEG acquisition system, thus the objective of this research. This study involves the following phases: Data Collection, Data Acquisition and Data Analysis. Target population are normal and healthy subjects of age between 18 and 25. The EEG signals are recorded with electrodes at activation areas along the documented signal pathway of the brain (C3, C4, P3, P4, O1, O2, T7, FC5) during reading and writing. Fast Fourier Transform (FFT) is applied to transform the EEG in time domain into frequency domain so that signature features in frequency content during relaxation and sentence writing can be extracted. Results showed that relaxation drew on one dominant peak and the frequency content resides in the alpha sub-band while writing activity drew on two dominant peaks, one in alpha and the other in beta sub-band. The frequency range of EEG recorded during relaxation is 8-13 Hz while that during writing is 13-29 Hz, well within the alpha and beta sub-band for the different neuro-activity accordingly. Hence, it can be concluded from experimental results and findings from previous works that electrodes C3/C4, P3/P4, O1/O2, T7 and FC5 are suitable as optimal localized EEG electrode placement for neuro-pathway for reading-writing.
DEVELOPMENT AND EVALUATION OF SOLID CONTROL SYSTEM TO OPTIMIZE DRILLING PERFORMANCE
Authors: Kinif Imros , Irawan Sonny , M. Bharadwaj Abhilash
Published: October 2019

The nature of solid content mechanism in drilling fluids directly affects its properties and causes adverse impact on drilling performance. It has rapidly evolved and become a paramount issue over the years because of challenging drilling operations. To control the impact of the drilled solids on drilling fluid properties, solid control system unit must be capable of removing the drilled solids before the re-circulation. Failure to establish good solid control management may end the operation strategy with dilution method. A rigorous analysis of drilled solid effects and its correlation with poor performance of solid control system significantly reflects on the overall rig performance in optimizing drilling operation. This paper presents a study of two different solid control system configuration used in two drilling wells. The study shows that installation of distributor tank reduces mud overflow and brings in flow control stability. Mud rheologies – Plastic viscosity, Yield Point and Low Gravity Solid are considered for the two solid control systems. The results of the new solid control system design are better than the old one. Plastic viscosity, yield point and low gravity solid values improve by 14 %, 17 % and 25 % respectively. These results can be used to check the drilling performance and also in characterization of the solid control system to enhance the drilling mud capabilities. This research shows the need of engineering evaluation in the solid control system to reduce the chances of frequent drilling problems, rig components wear issue and other drilling fluid related hazards.
NUMERICAL STUDY OF HYDROGEN FUEL COMBUSTION IN COMPRESSION IGNITION ENGINE UNDER ARGON-OXYGEN ATMOSPHERE
Authors: Hafiz Nik Muhammad , Abu Mansor Mohd Radzi , Wan Mahmood Wan Mohd Faizal , Ibrahim Fadzli , Abdullah Shahrir , Sopian Kamaruzzaman
Published: October 2019

Gas emissions from automobiles are one of the major causes of air pollution in our environment today. In fact, emissions of carbon dioxide (CO2), a product of complete combustion, has become a significant factor of the global warming effect. Hydrogen, which is a renewable energy, is regarded as a promising energy to solve this problem since the final product of hydrogen (H2) combustion, is water (H2O). However, the reaction of hydrogen fuels in the air under high temperature conditions produces a high volume of harmful nitrogen oxide (NOx). Furthermore, the high auto-ignition temperature of H2 makes it difficult to ignite in a compression ignition engine in normal air. In this research, argon (Ar) is used to replace nitrogen (N2), in order to eliminate NOx and enhance combustion. Simulation for this research was conducted using Converge, computational fluid dynamics software that is based on Yanmar TF90M compression ignition engine parameters. The simulation process was initially conducted with normal air (N2-O2) as the medium of combustion; but later it was replaced with an argon-oxygen (Ar-O2) atmosphere to investigate the ignition possibility of hydrogen fuel. Hydrogen was injected at 9.95 MPa at the start of injection (SOI) at 18º BTDC. The results show that, by employing the same parameters for both simulations in normal air and argon-oxygen mediums, the combustion of hydrogen only occurred in the argon-oxygen medium. However, no combustion took place in normal air. It is therefore concluded that an argon-oxygen medium is applicable for direct hydrogen injection in a compression ignition engine.
HANDLING EMERGENCE OF DYNAMIC VISUAL REPRESENTATION DESIGN FOR COMPLEX ACTIVITIES IN THE COLLABORATION
Authors: Ya’acob Suraya , Mohamad Ali Nazlena , Mat Nayan Norshita
Published: October 2019

In recent years, we observed a general trend in organization toward emerging information items in the complex cognitive activities (CCA). Since CCA occur in decision making, problem solving and sense making more in the collaborative settings, it becomes essential for business to response and act according to emerging information items to stay relevant in the market. However, the emergence of information which has been known as an ‘uncontrollable entities’ are hard to be determined from information system perspectives. Thus, the management team is having difficulties in utilizing the emergence information to become valuable outcomes for both organization and stakeholders. This paper aims to show how visualization can play an important role to facilitate this challenge. First, we present the emergence challenges from the perspective of relative isolation between the information, mental and representation spaces. Then, we highlight the importance of dynamic concept as a fundamental approach to handle emergence. We attempt to pin the second order cybernetic as an underlying theory for dynamic interactivity between visual representation and users’ mental space. By having this, we are able to construct the information evolvement during the cognitive process and manage their cognitive burden. Finally, we report the findings from qualitative analysis of experimental case studies within a collaborative setting dealing with complex activities (decision making) process. Our findings show the positive outcomes to centralize collaborators’ mental model, bring clarities and foster innovative thinking during the process of complex activities in the collaboration. Through this research, we have found the potential of dynamic visual structure to bring better values, practical and sufficient in handling complexities of information emergence during the collaborative CCA in the organization.
NFC BASED ATTENDANCE: MORE THAN JUST A TOUCH
Authors: Zuhedy Zay Aqqiela Zuhra , Mohd Nor Rizal , Mohamed Razi Mohamed Jalaldeen , Mantoro Teddy , Anugerah Ayu Media
Published: October 2019

The use of NFC technology is growing rapidly and implemented in various applications. It aims to reduce the steps needed to perform tasks by the user in day to day operations such as payment, electronic ticketing, attendance system, and other office related tasks. In this study, university smart environment is implemented using NFC for attendance monitoring system to reduce the need of tedious tasks. The application involves several different concerns in access control and managing physical and virtual components. These concerns are studied to create an easy-used attendance monitoring system using NFC to be applied in a smart university environment. A survey is conducted to measure students and lecturers acceptance in using NFC as an attendance monitoring system. The results provide insights on students and lecturers acceptance in using this technology. Additionally, it shows that both students and lecturers agree on the NFC attendance system should be implemented to ease attendance monitoring in the university.
Assessment of Thermo-Electric Power Plants for Rotorcraft Application
Authors: Roumeliotis Ioannis , Mourouzidis Christos , Zafferetti Mirko , Unlu Deniz , Broca Olivier , Pachidis Vassilios
Published: October 2019

This paper assesses a parallel electric hybrid propulsion system utilizing simple and recuperated cycle gas turbine configurations. An adapted engine model capable to reproduce a turboshaft engine steady state and transient operation is built in Simcenter Amesim and used as a baseline for a recuperated engine. The transient operation of the recuperated engine is assessed for different values of heat exchanger effectiveness, quantifying the engine lag and the surge margin reduction which are results of the heat exchanger addition. An oil and gas (OAG) mission of a twin engine medium helicopter has been used for assessing the parallel hybrid configuration. The thermoelectric system brings a certain level of flexibility allowing for better engine utilization, thus first a hybrid configuration based on simple cycle gas turbine scaled down from the baseline engine is assessed in terms of performance and weight. Following the recuperated engine, thermoelectric power plant is assessed and the performance enhancement is compared against the simple cycle conventional and hybrid configurations. The results indicate that a recuperated gas turbine based thermo-electric power plant may provide significant fuel economy despite the increased weight. At the same time, the electric power train can be used to compensate for the reduced specific power and potentially for the throttle response change due to the heat exchanger addition.
Theoretical and Experimental Investigation of a Small-Scale, High-Speed, and Oil-Free Radial Anode Off-Gas Recirculation Fan for Solid Oxide Fuel Cell Systems
Authors: Wagner Patrick H. , Van herle Jan , Schiffmann Jürg
Published: October 2019

The Laboratory for Applied Mechanical Design (LAMD) designed, manufactured, and experimentally tested a novel recirculation fan for a 10 kWe solid oxide fuel cell (SOFC). The fan uses oil-free bearings, more specifically herringbone-grooved journal and spiral-grooved thrust gas bearings. The radial inducer-less fan with a tip diameter of 19.2 mm features backward-curved prismatic blades with constant height. Prior to coupling the recirculation fan with the SOFC, the fan was experimentally characterized with air at 200 °C. At the nominal point of 168 krpm, the measured inlet mass flow rate is 4.9 kgh–1, the total-to-total pressure rise 55 mbar, the isentropic total-to-total efficiency 55%, and the power 18.3 W. This paper compares the experimental data toward a computational fluid dynamic simulation of the full fan impeller and volute suggesting an excellent correlation at the nominal point which validates the numerical approach. However, the heat flows crossing the fan fluid domain have an increased effect at off-design conditions; thus, the experimental results need careful consideration. The fan backface leakage has negligible impact on the measurements.
Effect of curvature of spherical microscopic indentations on the ellipsometric readout
Authors: Fischer Daniel , Griepentrog Michael , Beck Uwe , Duwe Matthias , Quast Jan-Henrik , Schneider Stefan
Published: October 2019

The authors describe and interpret curvature-related changes to the ellipsometric readout. As model system for a concave curvature, a set of three spherical microscopic indents in silicon (100) of different sizes was prepared by instrumented indentation testing using a spherical indenter. For reference, these samples were characterized by AFM to reveal the topography of each structure. The concavelike indents were analyzed by Mueller-Matrix imaging ellipsometry to extract lateral intensity images of 12 elements of the Mueller-Matrix. As a result of the detailed analysis of the image elements m22, m23, and m14, it was possible to correlate intensity changes and symmetry properties to depolarization and cross polarization induced by the edge threshold and the curved surface of the indent.
Differentiation of the Strength of Back Muscle Contraction Under Fatigue: Does Force Feedback Play a Role?
Authors: Zemková Erika , Jeleň Michal
Published: October 2019

Objective: This study investigates the ability of subjects to differentiate the strength of back muscle contraction with and without feedback information on force produced under fatigue and nonfatigue conditions. Design: Controlled laboratory study. Setting: Research laboratory environment. Participants: A group of 52 healthy young men participated in the study. Intervention: Subjects self-estimated 50% of the maximal voluntary isometric contraction of back muscles either on their own volition or on the basis of information about the actual force, before and after the Sørensen fatigue test. Main Outcome Measures: The force was measured by means of the FiTRO Back Dynamometer. Results: The self-estimated 50% maximal voluntary isometric contraction was significantly higher than the one calculated from maximal voluntary isometric contraction during 10 trials in 2 repeated sessions (8.3% and 10.0%, P < .05). However, when feedback on the force produced was provided, significantly higher values were observed during an initial trial in both sessions (8.5%, P = .04 and 12.1%, P = .01). Subjects were able to estimate the target force during the following trials. Fatigue induced a decrease in peak force (7.7%, P = .04), whereas the ability to regulate the prescribed force was not compromised. Constant error was lower with than without force feedback during both measurements (2.15% and 6.85%; 3.06% and 8.56%). However, constant and variable errors were greater under fatigue than nonfatigue conditions (8.43% and 5.55%; 0.41% and 0.37%). Similarly, root mean square error decreased with force feedback (from 6.88% to 3.48% and from 8.74% to 5.09%) and increased under fatigue (from 5.87% to 8.67%). Conclusions: These findings indicate that force feedback plays a role in the differentiation of the strength of back muscle contraction, regardless of fatigue. It contributes to a more precise regulation of force produced during voluntary isometric contraction of back muscles. This promising method awaits further experimentation to be applied for individuals with low back pain.
CARD9 mediates dendritic cell–induced development of Lyn deficiency–associated autoimmune and inflammatory diseases
Authors: Ma Jun , Abram Clare L. , Hu Yongmei , Lowell Clifford A.
Published: October 2019

Without the kinase Lyn, the adaptor protein CARD9 amplifies cytokine production in autoimmune disease.
The Ca
2+
export pump PMCA clears near-membrane Ca
2+
to facilitate store-operated Ca
2+
entry and NFAT activation
Authors: Go Christina K. , Hooper Robert , Aronson Matthew R. , Schultz Bryant , Cangoz Taha , Nemani Neeharika , Zhang Yi , Madesh Muniswamy , Soboloff Jonathan
Published: October 2019

The Ca
2+
export pump PMCA4 unexpectedly facilitates Ca
2+
entry and NFAT activation in T cells.
Reminder of an important clinical lesson: breast cancer metastasis to the parotid gland
Authors: Jakharia-Shah Amisha , Wheatley Hugh , Beesley Matthew
Published: October 2019

A 59-year-old woman presented to an otolaryngology clinic with an 8-week history of a painless lump over her left parotid gland. Her medical history included an invasive ductal carcinoma (33 mm) and a ductal carcinoma in situ (70 mm) of the right breast, for which she had a mastectomy and various adjuvant therapies. The primary tumour presented 8 years prior to the metachronous metastasis. This patient was a non-smoker and had no significant family history. Post-superficial parotidectomy pathology revealed the parotid gland tumour to be oestrogen receptor-positive and HER2 receptor-positive, thus ruling out the initial differential diagnosis of a pleomorphic adenoma. A consequential total parotidectomy with a posterolateral neck dissection was performed with sparing of the facial nerve. The patient recovered well having only encountered a self-resolving salivary fistula. She portrayed no signs of facial nerve palsy and subsequent imaging scans showed no abnormalities.
Non-alcoholic fatty liver disease and risk of incident acute myocardial infarction and stroke: findings from matched cohort study of 18 million European adults
Authors: Alexander Myriam , Loomis A Katrina , van der Lei Johan , Duarte-Salles Talita , Prieto-Alhambra Daniel , Ansell David , Pasqua Alessandro , Lapi Francesco , Rijnbeek Peter , Mosseveld Mees , Avillach Paul , Egger Peter , Dhalwani Nafeesa N , Kendrick Stuart , Celis-Morales Carlos , Waterworth Dawn M , Alazawi William , Sattar Naveed
Published: October 2019

Objective

To estimate the risk of acute myocardial infarction (AMI) or stroke in adults with non-alcoholic fatty liver disease (NAFLD) or non-alcoholic steatohepatitis (NASH).

Design

Matched cohort study.

Setting

Population based, electronic primary healthcare databases before 31 December 2015 from four European countries: Italy (n=1 542 672), Netherlands (n=2 225 925), Spain (n=5 488 397), and UK (n=12 695 046).

Participants

120 795 adults with a recorded diagnosis of NAFLD or NASH and no other liver diseases, matched at time of NAFLD diagnosis (index date) by age, sex, practice site, and visit, recorded at six months before or after the date of diagnosis, with up to 100 patients without NAFLD or NASH in the same database.

Main outcome measures

Primary outcome was incident fatal or non-fatal AMI and ischaemic or unspecified stroke. Hazard ratios were estimated using Cox models and pooled across databases by random effect meta-analyses.

Results

120 795 patients with recorded NAFLD or NASH diagnoses were identified with mean follow-up 2.1-5.5 years. After adjustment for age and smoking the pooled hazard ratio for AMI was 1.17 (95% confidence interval 1.05 to 1.30; 1035 events in participants with NAFLD or NASH, 67 823 in matched controls). In a group with more complete data on risk factors (86 098 NAFLD and 4 664 988 matched controls), the hazard ratio for AMI after adjustment for systolic blood pressure, type 2 diabetes, total cholesterol level, statin use, and hypertension was 1.01 (0.91 to 1.12; 747 events in participants with NAFLD or NASH, 37 462 in matched controls). After adjustment for age and smoking status the pooled hazard ratio for stroke was 1.18 (1.11 to 1.24; 2187 events in participants with NAFLD or NASH, 134 001 in matched controls). In the group with more complete data on risk factors, the hazard ratio for stroke was 1.04 (0.99 to 1.09; 1666 events in participants with NAFLD, 83 882 in matched controls) after further adjustment for type 2 diabetes, systolic blood pressure, total cholesterol level, statin use, and hypertension.

Conclusions

The diagnosis of NAFLD in current routine care of 17.7 million patient appears not to be associated with AMI or stroke risk after adjustment for established cardiovascular risk factors. Cardiovascular risk assessment in adults with a diagnosis of NAFLD is important but should be done in the same way as for the general population.