UTM Press Journal Management (Universiti Teknologi Malaysia)
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THE ACCEPTABLE COMPACTION ZONE CRITERIA BASED ON HYDRAULIC CONDUCTIVITY FOR A COMPACTED MIXTURE OF RESIDUAL SOIL WITH BENTONITE AS A SOIL LINER
No full textThe significant criteria for compacted clay liner in landfill construction are the compaction characteristics and hydraulic conductivity value. The primary parameter for designing an efficient soil liner is ensuring a hydraulic conductivity value below 1x10-9 m/s to prevent contaminated seepage into the aquifer. Therefore, the compaction criteria are crucial in controlling the construction of hydraulic barriers for liners. In this study, laboratory testing such as permeability tests at varying compaction energies, were carried out on a blend of residual soil and bentonite. The aim was to establish an acceptable compaction zone based on the allowable hydraulic conductivity value and to outline suitable design considerations for compacted residual soil mixed with bentonite as a soil liner. The design parameters investigated included hydraulic conductivity at different compaction efforts. A comparison was made between traditional, common, and modern approaches to ensure construction quality assurance for compacted soil liners mixed with bentonite. The results indicated that all methods, traditional, common, and modern, successfully met the design objectives for hydraulic conductivity, creating acceptable compaction zones on the compaction plane curve. These acceptable zones for the mixture of residual soil with bentonite align with the lower bound limit of the compaction optimum line, with the shapes of the shaded zones influenced by the soil\u27s moisture content and compaction characteristics
COMPARATIVE EFFICACY OF CONVENTIONAL STABILIZERS IN IMPROVING ENGINEERING BEHAVIOR OF EXPANSIVE SUBGRADES
No full textThis paper addresses the critical issue of distress in flexible pavements built on expansive Black Cotton soil, where seasonal moisture variations lead to swelling and shrinking, posing a serious threat to durability. Despite extensive research utilizing conventional stabilizers such as cement, lime, and fly ash, the comparative effectiveness of these stabilizers remains uncertain. This study employs a comprehensive approach, integrating conventional tests and microanalysis techniques to assess the engineering behavior of stabilized expansive soil samples. The investigation includes tests like Unconfined Compressive Strength (UCS) for strength evaluation, Free Swelling Index (FSI) for swelling potential estimation, and Atterberg’s limits for evaluating plasticity properties. Additionally, Environmental Scanning Electron Microscope (ESEM) microanalysis is employed to examine the morphology of uncured-unstabilized expansive soil samples and those stabilized with cement, lime, and fly ash after a 28-day curing period. Results indicate that cement emerges as the most effective stabilizer, significantly reducing swelling by up to 42% and increasing strength post-curing by a remarkable fivefold compared to unstabilized-uncured expansive soil. Lime demonstrates exceptional efficacy in reducing plasticity, diminishing Liquid Limit (LL) and Plasticity Index (PI) by 30% and 79%, respectively. In contrast, fly ash is identified as least effective stabilizer, displaying the lowest efficacy in reducing swelling, plasticity, and enhancing strength. Furthermore, the study extends its analysis to evaluate the impact of these stabilizers on rutting and fatigue life of pavements through Finite Element Analysis (FEA) using PLAXIS. The findings contribute valuable insights for practitioners and researchers seeking optimal stabilizer selection for expansive soil-based pavement projects
DESIGN AND ANALYSIS OF A MULTI-ARRAY AND OVERLAPPING CONNECTION USING PIEZOELECTRIC ENERGY HARVESTER
No full textThere has been much research done on energy harvesting by capturing vibration from low frequency energy. In essence, an array of piezoelectric connections is used to convert kinetic energy into electrical energy in order to produce low frequency energy. This paper presents an investigation on vibration energy harvesting which compares the performances of array piezoelectric connection. This research utilized maximum three pieces of circular piezoelectric sensor which adequate to test the combinations of array connection. Selection of the piezoelectric sensor array are series, parallel, series-parallel, parallel-series and overlapping. The observation is finding the highest power output between array piezoelectric connections. The result show that 3P piezoelectric connection obtained a higher power output among the other types of array piezoelectric which was 3.12 mW
ASSESSMENT OF SCATTERED X-RAYS TO THE THYROID GLAND OF RADIATION WORKERS IN COMPUTED TOMOGRAPHY (CT) ROOM
No full textComputed tomography (CT) scan is widely used as a rapid and decisive diagnostic method. During CT examinations part of the radiation is scattered from the device. In normal practice, only patient will be allowed to presence inside CT room during examination. However, in some cases medical staff must remain in the CT room. This work aims to study the amount of scattering radiation during CT examinations at Al-Zahraa Hospital, Diyala, Iraq and assess the radiation impact on the thyroid gland hormones for radiation workers to evaluate the severity of the radiation exposure. All data were collected during the month of May to June, 2022. The results showed that the highest amount of scattered radiation was 18.55 mSv in front of the CT gantry head and the lowest scattered radiation was found at both sides of the CT scan device with values of 0.28 mSv and 0.27 mSv. The study also evaluated the impact of scattering radiation on the thyroid gland by testing the triiodothyronine and thyroxine hormones, together with the stimulation hormone in blood from 50 respondents of different gender, age and working time in the CT examination room. The test results showed that the probability of developing thyroid gland disorder increases for radiation workers in comparison to non-radiation workers. These effects were more severe for radiation workers with longer duration of work inside the ionizing radiation units. Thus, exposure to ionizing radiation increases the risk of developing a thyroid gland disorder for workers in CT scan unit
NUTRITIONAL POTENTIAL OF DRIED SEAWEED Turbinaria decurrens: BIOCHEMICAL INSIGHTS AND HEALTH BANEFITS
No full textTurbinaria decurrens, the tropical brown seaweed, was analyzed for its biochemical composition, which includes proximate, fatty acid, amino acid, and mineral contents. This research aims to investigate the feasibility of utilizing brown seaweed as an alternative source of human nutrition derived from the ocean. Proximate (moisture, fat, ash, protein, and carbohydrate) and minerals (calcium, sodium, potassium, magnesium, and iron) were determined by the standard method of AOAC. In contrast, phosphor was determined by the spectrophotometric method. Amino acid was determined by Ultra Performance Liquid Chromatography and fatty acid by gas chromatography. The results indicated that the significant proximate content was carbohydrates, ash, moisture, protein, and fat, which were 61.44%, 16.73%, 15.78%, 4.34%, and 1.71%, respectively. The primary mineral content was calcium, potassium, magnesium, sodium, phosphor, and iron, which were 42,991 mg/kg, 19,222 mg/kg, 10,402 mg/kg, 8,180 mg/kg, 237 mg/kg, and 166.9 mg/kg, respectively. The significant component of saturated fatty acids was palmitic acid, myristic acid, lauric acid, and stearic acid, which were 0.61%, 0.08%, 0.08%, and 0.06%, respectively. The two significant monounsaturated fatty acid components were oleic acid and palmitoleic acid, which were 0.39% and 0.04%, respectively. In comparison, polyunsaturated fatty acids were arachidonic acid, linoleic acid, linolenic acid, eicosatrienoic acid, and eicosapentaenoic acid, which were 0.19%, 0.1%, 0.07%, 0.02%, and 0.02%, respectively.
ENHANCING RARE EARTH ELEMENTS STABILITY IN ION ADSORPTION CLAYS DURING ION-EXCHANGE LEACHING WITH SALT SOLUTIONS: A THERMODYNAMIC APPROACH THROUGH POURBAIX DIAGRAMS
No full textRare Earth Elements (REEs) are typically extracted from ion adsorption clays using the ion-exchange leaching method, which involves a salt solution as the leaching solution. To maximize REE leaching efficiencies, it is crucial to maintain the thermodynamic stability of REEs in the salt solution during the extraction process. Therefore, a thermodynamic approach through the Pourbaix diagram was conducted by using HSC Chemistry 10.0 software. In this study, the three most significant REE concentrations in ion adsorption clay- lanthanum (La), neodymium (Nd), and yttrium (Y)- were tested using different sulfate solutions (ammonium sulfate, magnesium sulfate, and aluminum sulfate) across concentrations ranging from 0.05 to 0.6 M and temperatures from 25 to 80 °C. The Pourbaix diagrams analysis demonstrated that magnesium sulfate solution was the most effective leaching solution, providing the maximum thermodynamic stability for La, Nd, and Y within a pH range of 0 to 5.8, across all tested concentrations, without any chemical formation occurring within that region. Additionally, the stability of La, Nd, and Y was found to decrease as the leaching temperature increased. Since 25°C proved to be the optimal temperature in this study, it suggests that ion-exchange leaching can be efficiently performed at ambient temperature, eliminating the need for external heating during the extraction process. In conclusion, using magnesium sulfate as a leaching solution at ambient leaching temperature enhances the thermodynamic stability of REEs in ion adsorption clay during ion-exchange leaching, leading to improved REE extraction and reduced impurity formation
COBOT – ASSISTED REHABILITATION: REDUCING WORK-RELATED MUSCULOSKELETAL DISORDER (WMSD) RISK ON PHYSIOTHERAPISTS
No full textRecent studies report that 40% to 90% of physiotherapists globally experience WMSDs due to repetitive movements and poor postures during manual rehabilitation therapy. This study aims to evaluate the potential effectiveness of collaborative robot (cobots) in reducing ergonomic risks and preventing WMSDs among physiotherapists. Seven male participants, acting as simulated physiotherapists recruited through convenience sampling performed passive range of motion (PROM) tasks for lower extremity rehabilitation with and without cobot assistance. Full-body motion tracking was carried out with seventeen inertial measurement unit (IMUs) and muscle activation via electromyography (EMG) electrodes. A UR16e cobot was utilized to support the patient’s limbs during rehabilitation exercises, while simultaneously synchronizing biomechanical data collected from a Bertec force plate and motion tracking via an Xsens system. Ergonomic risks were assessed using the REBA tool, and spinal loading was analyzed with the 3D Static Strength Prediction Program (3D SSPP). The Wilcoxon Signed-Rank Test compared cobot-assisted and conventional methods. With cobot assistance, the left biceps brachii activation during hip abduction adduction decreased from 63.95% ± 26.10 %MVIC to 6.09% ± 5.13 %MVIC, while the right erector spinae activation during hip flexion decreased from 54.97% ± 27.82 %MVIC to 8.35% ± 5.03 %MVIC. The REBA score decreased considerably from 8.77 ± 1.50 to 3.68 ± 0.35 during knee flexion and extension tasks. Lumbar compression forces (L5-S1) decreased from 3276.57 ± 109.90 N to 1176.29 ± 40.87 N. All p-values were < 0.05, indicating significant differences between both approaches on all parameters.
UFREN WORKER: A USER-FRIENDLY MOBILE APPLICATION SOFTWARE TO IMPROVE CONSTRUCTION SITE COMMUNICATION
No full textEffective communication among project participants in construction site is a real dilemma for construction projects productivity. To improve the efficiency of participants in construction projects and ensure a speedy delivery of these projects, this research presents the development of a mobile-based project monitoring system to support construction site communication. In line with the Industrial Revolution (IR) 4.0 as mobile phone as Internet of Thing (IoT), the mobile apps (Ufren Workers Mobile Apps) is designed to enhance or improve communication between project manager, site supervisors and site workers at the construction sites. Development of Ufren Worker was conducted based on the main objectives; current requirement existing mobile-based apps, real-time progress tracker features and validate the practicality of user friendly mobile-based project monitoring system to construction site team. The analysis was conducted on developed program according to its practicality and suitability. There were 11 respondents involved as beta-users to evaluate their satisfaction level and validation rating on the Ufren Workers Mobile Apps from the questionnaire given. Overall, Ufren Workers Mobile Apps scored 4.5 (good) mean in total based on perception toward satisfaction evaluation that has been rated. Ufren Workers Mobile Apps provide simplicity of system, good optimization, attractive user interface design, useful updating progress and top notch performance. Nonetheless, features on Ufren Workers Mobile Apps should be upgraded due to the demand of technological growth. There are many competitors developing mobile worker apps in the market that provide the latest features with good optimization. This app is imperative to facilitate communication in construction sites, which is much needed in this information intensive sector
LOAD VARIATIONS BASED OPTIMAL REACTIVE POWER SUPPORT FOR HIGH ECONOMIC GAIN IN DISTRIBUTION ELECTRIC POWER NETWORK
No full textProblems such as high impedance, below normal bus voltages, and Load density of the Distribution Electric Power Network (DEPN) lead to a rise in power losses (real and reactive power losses) with large deviations in node voltage profile. For DEPN planning and operation studies, the power and voltage deviation have been significantly apprehensive. For the past five decades, several researchers have been focusing on DEPN to reduce Power losses to the minimum level. Sitting and sizing of Shunt Capacitor Banks (SSSCB) optimally in the DEPN is of greatest importance in reducing the power losses, power factor improvement, and voltage profile upgradation thereby more Economic Gain (EG). The target of this study is to enhance the performance of the DEPN using Reactive Power Support (RPS) under three different load levels to minimize the capacitor investment cost and maximize the difference in kWh and kVARh using the Sea-Horse Optimizer Algorithm (SHOA). The proposed algorithm has been witnessed with the help of two general test systems (PG&E 69 bus and Indian 118 bus) and one real DEPN (28 bus system, PEA, Thailand). The overall % power loss reduction ranging between 29% and 37% has been observed across the three load variations for all the three test systems. Simulation results reveal that significant improvements in technical and EG are fulfilled which confirms the prospective of the proposed RPS procedure
A CONCEPTUAL FRAMEWORK FOR FLOOD DISASTER PREVENTION ASSESSMENT IN MALAYSIA
No full textFloods are among the most destructive natural disasters globally and Malaysia lacks a standardized and comprehensive framework for flood disaster prevention assessment. Existing guidelines focus mainly on emergency response and recovery with limited integration of proactive prevention measures. This study aims to address the gap by developing a conceptual framework for flood disaster prevention assessment tailored to the Malaysian context. A qualitative methodology was adopted involving semi-structured interviews with seven domain informants from the National Disaster Management Agency (NADMA), Department of Irrigation and Drainage (JPS) and the Public Works Department (JKR). Thematic analysis of the interview data identified five core components of flood disaster prevention such as risk assessment, early warning systems, floodplain management, structural and non-structural measures. Furthermore, critical variables influencing assessment effectiveness were identified including topography and hydrology, climate and weather patterns, infrastructure conditions and socioeconomic factors. These elements were systematically integrated into the proposed Flood Disaster Prevention Framework (FDPF), which was then validated through expert review. The framework is intended to enhance inter-agency coordination and strengthen national flood resilience. This research offers a strategic tool to support policy formulation and operational planning in flood disaster risk reduction across Malaysi