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The design of manmade water stream and landscape for water conservation and community project development / Fong Mei Yong
No full textThis study is for the water conservation and community development project in Rumah Hutan Jeram. In this project, we had proposed a design of the manmade water stream and the landscape design of the Rumah Hutan Jeram. To come out with the design plan and idea, we will first need to determine the water source for the manmade water stream. We had identified the groundwater potential ranking using the GIS methods and estimate the groundwater recharge rate. From the geological data and the remote sensing data, it had shown that the Rumah Hutan Jeram area is high groundwater potential. On the other hand, the groundwater recharge rate is in between 247mm - 265 mm. These data had shown that the existing borewell is sufficient to support the water stream. This project analysed the designed and planned of the manmade water stream and the surrounding landscape with the aid of Geographical Informative System (GIS) and Remote Sensing. Rumah Hutan Jeram was designed according to the theme of natural and sustainable concept. This research project has some important criteria and adheres to the concept of water and energy conservation. In this research, the risk assessment and control measure were also included, and it is suggested according to the landscaping construction activities
Assessment and mitigation of university student's mental health during COVID-19 / Hasanathul Bashariyah Kamaludeen
No full textIn higher education, student mental health has become a growing problem. The
COVID-19 pandemic has refocused attention on this vulnerable group. This study seeks
to provide a comprehensive assessment of the impact of the COVID-19 pandemic on
university student’s mental health. To assess the mental health status of public university
students in Malaysia, an online survey using GAD-7 and PHQ-9 screening tests was
conducted with 200 students and the data was analyzed through quantitative methods.
The mental health statistical analysis using IBM Statistical Product and Service Solutions
(SPSS) version 27.0 revealed that the 88 students (44.00%) were highly experiencing
mild anxiety symptoms. Whereas, 74 students (37.00%) were highly experiencing mild
depressive symptoms during this COVID-19 outbreak. However, significant findings reported that 25 students (12.50%) and 24 students (12.00%) have severe anxiety and depressive symptoms respectively. The level of anxiety, depression of the students and the duration of the students staying alone or away from the family has a significant correlation with each other of at least r=0.147. These findings have encouraged the researcher to propose a mitigation model for universities to address mental health issues
among university students
The effectiveness of electrocoagulation process in latex wastewater treatment in comparison to conventional physical treatment / Praimon N Janagarajan
Get PDFdistance (cm) and time (seconds). Using the optimal values obtained, other parameters of
the wastewater sample were analyzed to determine if Department of Environment (DOE)
Standard B criteria could be achieved or not. There was significant reduction in the pollutant parameters in comparison to the conventional physical treatment which has been installed in the selected company. This shows that electrocoagulation is an efficient treatment process in the treatment of wastewater from latex industry. But
electrocoagulation alone could not achieve DOE Standard B effluent discharge standard. The aid of biological treatment is required to further reduce the pollutant concentration
Creep damage analysis and numerical simulation on oil well steel pipe casing at elevated temperatures / Sarmad Khubaib Sarajun Hoda
No full textThe purpose of this study was to investigate the Creep Damage Analysis and Numerical Simulation on Oil Well Steel Pipe casing at Elevated Temperatures using ANSYS (Computational Structural Analysis). Creep deformation is a type of plastic deformation of solid materials which occurs under high constant stress at high temperatures. Primary purpose of an Oil Well casing is to transport crude oil to the surface as well as separates the fluid or solid of inside the wellbore from the outside environment, whether in solid or in water. Casings of an oil well can experience tremendous pressure change during hydraulic fracturing processes or steam injection processes. The operating loads added with harsh conditions deep beneath the ground or in seawater exerts very high stresses on casings throughout their lifetime Analysis suggest that numerous failures of the casings have been scrutinised, however they only shed minor lights in terms on how these failures occur in terms of the life. Wellhead uplift was detected among some oil wells, and development of offshore thermal recovery technology could be restricted by the serious safety problems behind. This paper is based on the specific operating conditions of one oil well in the trial block, and the simulation calculation of casing elongation and wellhead uplift are conducted by using finite element analysis. The total casing elongation calculated is 4.2 cm. According to the research, we concluded that the wellhead uplift is caused by upper casing elongation. 88% of the total elongation happens in the air and seawater sections. Elongation is lesser in strata and the casing string below 360 m can be considered as anchored. The maximum total deformation was 1.4645 x 10-7m, average elastic strain was 1.084 x 10-8 m/m, whereas the average volumetric change is 0.30042 m3
Environmental noise exposure at kernel crush point / Satwinder Singh Narangan Singh
No full textIn nearly every industry on the globe, noise pollution is a major problem. This article
is a study of noise exposure at Kernel Crush Point's production area. The study's major
goal is to determine noise exposure, compare noise levels to regulatory requirements, and
compare current and previous noise levels (2016 and 2019). The methodologies utilized
in this study were the Statistical Package for the Social Sciences (SPSS) Version 23.0.
According to the findings, there was an excessive amount of noise present, which was
usually over the action level as compared to the legal standard. There was no correlation
between noise levels and machine line. There was a substantial variation in noise levels
between recent and previous years (2016 and 2019). The proposal should be based on the hierarchy of control, which has been approved by many health and safety organizations. The five major components of the hierarchy of control are elimination, substitution, engineering control, administrative control, and personal protective equipment.
Management should offer improved personal protective equipment (PPE) with a greater noise reduction rating (NRR) to reduce sound exposure in the workplace
Cleaner production approaches in drilling-fluids engineering / Uma Magesan Ulakanathan
No full textDrilling-fluids or “mud”, as commonly known in the oil and gas industries, are very instrumental from the early stage of spudding to the completion phase of a well development.
Currently, majority of the drilling-fluids utilized are either water-based which is prepared by mixing various types of chemicals on the offshore drilling rig itself, or synthetic oil-based which is recycled from previous drilling campaign. Drilling-fluids residues from dead
volume of mud tanks, drilled cuttings and contaminated drilling-fluids from various operations are usually discharged directly to the sea. In addition, many of the support operations and practices in managing drilling fluids are less environmentally friendly. These practices may cause seawater pollution, which is hazardous to the micro aquatic life and overall marine environment. Therefore, in this study, an overall assessment was conducted for the full life cycle of drilling-fluids management to identify possible greening opportunities using cleaner production strategy. Subsequently, cleaner production (CP)
options were generated and evaluated in the perspective of carbon footprint. From this initiative, a general guideline that can be used to green drilling-fluid related operations were developed in order to reduce contamination of marine environment. To meet the objectives,
a CP audit was conducted in an offshore rig site which was executing a drilling operation from top section to reservoir section. Based on the analysis, carbon footprint could be reduced from 48.0 kg to 39.3 kg of carbon dioxide (CO2) / footage drilled with all the CP options proposed in all four intervals. This is equivalent to 18.2 % of reduction from total of 520.9 MT CO2 emitted throughout the drilling operations without considering any CP strategies.
ii Meanwhile, batch drilling technics could be considered as the finest CP option among all.
The contribution of batch drilling can be significantly observed via optimization of fluids
volume and materials in first and fourth interval
Compensation for three-coil wireless power transfer for misalignment and efficiency improvement in wireless charging system / Peyman Darvish
No full textWireless power transfer (WPT) using two or more magnetic resonance is commonly known as inductive power transfer ( IPT ). This technology can transfer power over distances without physical contact, offering significant benefits to modern automation systems duo its convenience, environmentally friendly, and efficient power transfer. Two coil WPT system is the most popular design over the past decades. However, recent studies have proven that a three-coil WPT design shows better performance and has higher efficiency compared to the two coil designs. This is especially critical when the source resistance and transmission distance between the primary and receiver coil increases.
Li-ion batteries are the most commonly used batteries for Electric Vehicles ( EVs ) applications because of their longer cycle life, higher power density, and improved battery safety. A constant current ( CC ) charging process followed by a constant voltage ( CV ) charging mode is the preferred charging technique for Li-ion batteries. Generally, in the first stage of battery charging which is commonly known as CC mode, the battery voltage rises quickly until it reaches its predetermined voltage level while the current remains the same. In the second stage of the charging process, the battery voltage remains constant, and the magnitude of the current begins to reduce. Once the current drops to almost zero, the charging process will be stopped. This technique of charging has been adopted in Two-coil WPT systems. Moreover, Zero Phase Angle conditions ( ZPA ) for both modes could be achieved to reduce the reactive power, increase efficiency, and prevent the hard switching of the MOSFETs.
Three-coil WPT system, similar to two-coil system, is capable of achieving constant output current and constant output voltage with ZPA. However, in the CV mode of the conventional three-coil design, the efficiency of the light load system dramatically
decreases as the load becomes smaller. Genreallly, In this work, a new Series-Series- LCLCC (S-S-LCLCC) compensation design for three-coil WPT system with load-independent output voltage, which is capable of realizing ZPA characteristics during the entire process of charging process, is proposed. The new design is capable of significantly improves the energy efficiency stiffness against the load variation, misalignment, increases the flexibility to optimize the system efficiency, reduces the voltage stress and increases the power delivery to load compared to the conventional topology. Moreover, the quality factor analysis for both conventional and the new design has been simulated, and the results show the novel system has the potential to improve the overall performance. The lab-made experimental design of a three-coil S-S-LCLCC WPT system with power rating of 420W and 96 V output voltage shows that the overall trend of efficiency of the proposed design is higher than the conventional S-S-S design as the load decreases and the new system has approximately 10% higher efficiency when the battery equivalent load resistance reaches 222 Ω. Moreover, the new design shows much better performance than the conventional system in the case of misalignment. Simplified models of S-S-LCLCC and S-S-S have also been successfully proposed and tested in this work to ease the simulation and the theoretical analysis
Investigation of the binding characteristics of anti-malarial drugs, mefloquine, lumefantrine and pyrimethamine to human serum albumin using spectroscopic and molecular docking methods / Kabiru Abubakar Musa
No full textAntimalarial drugs play a major role in the malaria therapy. Some of the FDA-approved antimalarial drugs, which are currently being used to treat malaria are mefloquine (MEF), lumefantrine (LUM) and pyrimethamine (PYR). Efficacy of a drug can be assessed based on its action on reaching a target tissue, which can be facilitated by a transport protein through circulatory system. Binding of MEF, LUM and PYR to human serum albumin (HSA), the main carrier protein in human blood circulation was investigated using fluorescence quenching titration, UV-vis absorption and circular dichroism (CD) spectroscopic techniques as well as molecular docking. Quenching of the protein (HSA) fluorescence induced by these drugs was characterized as static quenching, based on the decrease in the value of the Stern-Volmer constant, Ksv with increasing temperature, and/or the value of the bimolecular quenching rate constant, kq, which was found higher than the maximum kq value (2 × 1010 M ̶ 1 sec ̶ 1), reported for collisional quenching. These observations suggested the formation of drug-HSA complex, which was also confirmed from the UV-vis absorption spectral results. Values of the association constant, Ka for MEF/LUM/PYR ̶ HSA interactions were found to lie within the range, 1.32 ̶ 7.27 × 104 M ̶ 1, which indicated moderate binding affinity between these drugs and HSA. Non-covalent forces such as H-bonds, hydrophobic interactions and van der Waals forces were predicted to stabilize drug-HSA complexes, as revealed from thermodynamic data as well as molecular docking results. Far-UV and near-UV CD spectral results demonstrated smaller changes in both secondary and tertiary structures of HSA upon drug binding, while microenvironmental alterations around protein fluorophores (Trp and Tyr) were manifested by three-dimensional fluorescence spectra. Drug binding to HSA offered stability to the protein against thermal stress. The effect of a few metal ions on the drug binding characteristics of HSA was also noticed. Competitive drug displacement results as well as molecular docking analyses designated Sudlow’s Site I, located in subdomain IIA of HSA, as the preferred binding site of these drugs on HSA
Comparison of performance of no-clean and water-soluble fluxes in fine-pitch flip-chip package / Saif Wakeel
No full textThe complexity of cleaning caused by miniaturization of electronic packages and the drive towards cost reduction have recently led to the development of no-clean fluxes (NCF). In this study, characterization and effect of two commercial NCF namely NC-1 and NC-2 on the fine pitch flip-chip package were studied. One water soluble flux was also used for comparison. Characterization of these fluxes and their residues were done using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Hygroscopicity of the residue was investigated using water contact angle tests on residue contaminated substrate. Wettability of pre-printed SAC-305 solder on copper substrate was evaluated using the contact angle method. These fluxes were used to fabricate 17x17 mm2 flip-chip packages with fine pitch (150 μm) solder bump and copper pillar based . The formation of interfacial intermetallic compounds (IMCs) was observed using Field emission scanning electron microscopy (FESEM). Die pull strength of solder bumps was evaluated and failure mode was investigated. The quality of the flip-chip assembly was examined by non-destructive methods e.g., 2D radiography and confocal scanning acoustic microscopy (C-SAM). Moisture sensitivity of the package was evaluated using JESD22-A113D (30 oC/60% relative humidity (RH), 192 hours, 3x reflow at 260 oC). Thermal cycling test was performed following JESD22-A104D ( -65 oC to 150 oC) for 2000 cycles. High temperature storage life of package was determined using JESD22-A103C (175 oC) for 2016 hours. Results showed that three carboxylic acids, tertiary amine and ether were present in NC-1. The presence of one carboxylic acid, secondary amide and ether were observed in NC-2. Water soluble flux (WS) showed the presence of carboxylic acid, secondary amine, ether and alcohol. Flux residue showed the presence of carboxylic acid
iv
and amine for NC-1 and only amide for NC-2. Accelerated evaporation of certain monocarboxylic acids and ether solvent in NCF led to minimal residue as compared to WS. The residue of WS was highly hygroscopic as compared that of NCF’s. Wetting of solder bumps was better for using NC-1 and NC-2 than for WS which could be attributed to flux chemistry. Consequently, higher die pull strength was noticed for NCF immediately after assembly. Average die pull strengths for NCF were 10-17% higher than WS. However, in the moisture sensitivity test, 15.62% of NC-1 and 3.1% of NC-2 treated assemblies exhibited failure. Whereas WS cleaned assembly did not show any failure. During temperature cycling tests, solder bump crack was detected 500 cycles for NC-1 after whereas, crack for NC-2 occurred after 1500 cycles. Cleaned assembly did not show any crack and delamination. Thus, although NCF treated assemblies exhibited higher die pull strength immediately after reflowing. However, they performed poorly in moisture sensitivity and temperature cycling tests
Validation of the Malay version of the anticipatory and consummatory interpersonal pleasure scale (ACIPS): Comparison between schizophrenia patients and healthy subjects / Kohini C Balasingam
No full textBackground The reduced capacity for social and interpersonal interactions, or social
anhedonia, is regarded as an important facet of various psychiatric disorders. Its
recognition has many important implications in the clinical setting. Though there are
several measures to assess anhedonia, there are very few which specifically target the
social aspect. A more recent scale is the Anticipatory and Consummatory Interpersonal
Pleasure Scale (ACIPS). The goal of the present study was to validate the Malay version
of the ACIPS for use in the Malaysian context. Method The study was cross-sectional
in design and consisted of 95 schizophrenia patients and 300 healthy subjects.
Participants were given Malay versions of the ACIPS, Snaith Hamilton Pleasure Scale
(SHAPS-M), and Beck Depression Inventory (BDI-M) to assess their hedonic capacity.
Result The Malay version of the ACIPS exhibited good internal consistency
(Cronbach’s alpha = 0.875) and good concurrent validity. Exploratory factor analysis
(EFA) yielded a single factor solution. Item 1 on the scale did not correlate with the
other items. Receiver Operating Characteristics (ROC) analysis demonstrated a cut-off
value of 90 on the Malay version of the ACIPS to distinguish between schizophrenia
patients and healthy subjects. This score had a sensitivity of 89.4%, specificity of
83.7%, positive predictive value of 63.5%, and negative predictive value of 96.1%.
Conclusion The Malay version of the ACIPS is a promising tool with good validity and
reliability for assessing overall social anhedonia. Additionally, it is relatively short and
easy to administer, making it useful in the clinical setting.
Keywords: social anhedonia, schizophrenia, Malaysia, ACIPS, validatio