A review of assembly line balancing optimisation with energy consideration using meta-heuristic algorithms

Energy utilisation is one of the global trending issues. Various approaches have been introduced to minimise energy utilisation especially in the manufacturing sector, which is the largest consumer sector. One of the approaches includes the consideration of energy utilisation in the Assembly Line Balancing (ALB) optimisation. This paper reviews the ALB with energy consideration from 2012 to 2020. The selected articles were limited to problems solved using meta-heuristic algorithms. The review mainly focusses on the soft computing aspect such as problem variant, optimisation objectives, energy modelling and optimisation algorithm for ALB with energy consideration. Based on the review, the ALB with energy consideration was able to reduce energy utilisation up to 11.9%. It was found that the contribution in future ALB with energy research will be human-oriented, either social factor consideration in optimisation or energy utilisation modelling for workers. In addition, the effort to introduce an algorithm with efficient performance must be pursued because ALB problems have become more complicated. The findings from this review could assist future researchers to align their research direction with the observed trend. This paper also provides the research gap and research opportunities in the future

Modelling of assembly line balancing with energy consumption

One of the most gravitate issues in the world is energy usage. As the largest consumer in terms of energy usage, the manufacturing sector had introduced a lot of approaches to decrease their energy utilization. As the energy usage issue becomes more prominent, researchers had applied the Assembly Line Balancing (ALB) optimization that considers energy utilization as one of their efforts in reducing energy consumption. This paper discusses the related papers done by researchers, demonstrates the ALB model developed with electrical energy consideration by the application of the Matlab simulation and its validation through the manual hand calculation. The ALB with Energy Consideration (ALB-EC) was modelled into a mathematical model that could be used in solving the Simple Assembly Line Balancing Problem (SALBP), with the application of the Matlab application. The Particle Swarm Optimization (PSO) algorithm was applied and the model was tested by using three problems which consist of each of a small, medium, and large-sized test problem. Based on the finding, we could achieve the same results on the computational method along with the manual hand calculation for the evaluated total energy and objective functions. Besides, the advantages and limitations of the proposed model were also discussed in this paper. Through the application of this study, it could contribute to the reduction of electrical energy usage in the production line, which can reduce the overall energy usage CO2 gas production and prevent climate change

Self-perceived anxiety symptoms and its associated factors among type 2 diabetic patients in rural communities of Malaysia / Azlina Wati Nikmat, Mohd Ariff Fadzil and Sakinah Idris

Little is known about anxiety symptoms among diabetic patients, especially among those who are living in rural areas in Malaysia. Thus, the aim of this paper is to investigate the prevalence of anxiety among diabetic patients and factors associated with anxiety in rural communities in Malaysia. Methods: A cross-sectional study involving 464 diabetes mellitus patients in rural health districts and outpatient clinics in Malaysia was conducted. Each participant was interviewed using the Hospital Anxiety and Depression Scale. Results: Respondents consisted of 193 (41.6%) males and 271 (58.4%) females. The mean age of participants was 59.65 ± 10.16 years and the mean duration of diabetes mellitus was 6.9 ± 6.3 years. Results indicate that 15% of the participants have anxiety symptoms. Multiple logistic regression analysis revealed that patients with history of ischemic heart disease and depression and those who were underweight have higher anxiety scores with adjusted OR 5.06 (95% CI 1.79 to 14.27), 27.71 (95% CI 14.23 to 53.98) and 14.6 (95% CI 2.49 to 84.82), respectively. Conclusions: This study suggests that although the prevalence of anxiety among diabetics is low, primary care physician should be trained to identify high risk patients and to manage their condition in order to improve the clinical outcome

Depression among secondary school students: a comparison between urban and rural populations

Introduction: Childhood depression is a debilitating psychiatric illness and has frequently been under-diagnosed. It is crucial to identify the condition early, as undetected cases may lead to detrimental psychosocial consequences in adulthood. Objective: The prevalence of depression among school children in Selangor and to compare it between urban and rural schools. Also to identify factors associated with depression in secondary school children. Method: 2 urban and 3 rural secondary schools were selected by 2-staged stratified random sampling to represent the population of secondary school children in the state of Selangor, Malaysia. A total of 2,048 school children were enrolled and the level of depression was measured by a self-rated scale, the Children’s Depression Inventory. Results: This study found that the prevalence of possible depressive students in Selangor was 10.3%. There was no difference in the prevalence of depression between rural and urban population. Factors associated with depression were being female, Chinese, parents with low educational level, and high number of siblings, smoking and alcohol abuse. Depression contributed significantly to suicidal tendencies. Conclusions: A sizable proportion of the secondary school children in this population potentially suffer from depression. Psychological interventions are needed to ease this psychological burden and ensure their well being. Key words: Depression, secondary school students, factors associated

Characterisation of cholinesterase and histopathological features of brain of Clarias gariepinus following exposure to cadmium

Aim : Cholinesterase (ChE) inhibition and histopathological features of brain tissues of Clarias gariepinus were investigated with a purpose to develop biomarkers for monitoring heavy metals. Methodology : The effects of cadmium toxicity on were assessed by ChE inhibition and characterisation of ChE by affinity chromatography and histological variations in brain tissues were studied by H&E staining under light microscope. Results : The purified enzyme gave 10.58 fold purification with the recovery of 12% with specific activity of 159.729 U-1 mg . The Michaelis-Menten constant (K ) m and V value obtained was 1.985 mM max -1 -1 and 0.4479 µmol min mg , respectively. The enzyme showed the ability to hydrolyse acetylthiocholine iodide (ATC) at a faster rate compared to other two synthetic substrates, propionylcholine iodide (PTC) and butyrylthiocholine iodide (BTC). ChE showed highest activity at 35°C in Tris-HCl pH 7.5. The metal inhibition study also found the maximal inhibitory concentration (IC ) 50 -1 value for cadmium to be 0.6517 mg l . Histological study revealed decrease in the number of cells, degeneration of Purkinje cells, increased aggregation area and cells necrosis. Interpretation : Inhibition of cholinesterase activity and degeneration of Purkinje cells observed in the present study can be used as a tool for further developing a biomarker for detecting heavy metals in the aquatic ecosystems. C. gariepinu

Histopathological and cholinesterase changes in the gills of Clarias gariepinus as a result of cadmium exposure

Aim : The cholinesterase (ChE) based inhibition and histopathological studies from fish were investigated and represented in this study to develop as one of the great potential biomarkers for heavy metals monitoring. Methodology : In this study, the histopathological study of gills were observed a under microscope. The capability of ChE extracted from the gills of Clarias gariepinus was assessed for declining Cd. ChE was purified through affinity chromatography and continued with the optimisation and inhibition study (IC50) of cholinesterase. Results : Histopathological study of gills was carried out and several changes such as aneurysm, necrosis and lamella fusion were noted. Purification fold obtained from purified enzyme was 1.15 with 30% a yield specific activity 20.726. The optimum temperature for purified AChE was 35°C along with acetylthiocholine iodide (ATC) as a preferable substrate that had the highest Vmax value of 0.5452 U mg'1 and the lowest Km value of 0.0311 mM. The optimum pH was observed to be 10 of Tris-HCl as a medium. Meanwhile, the IC50 of cadmium was 6.808 mg ľ with R2 value of 0.9532. Interpretation : The result of the study can be used as a tool for further developing a biomarker for the detection of heavy metals in aquatic ecosystems. In addition, the baseline data provided can also be used for designing a kit, which would give rapid and accurate result

Translation, validation and psychometric properties of Bahasa Malaysia version of the Depression Anxiety and Stress Scales (DASS)

Background: Up to date, there are handful questionnaires that have been validated in Bahasa Malaysia (BM). This study aimed to translate the Depression Anxiety Stress Scales 21-item (DASS-21) and measure its psychometric properties. Objectives: To determine the construct validity and acceptability of the DASS, BM. Methods: Two forward and backward translations were done in BM in accordance to guideline, and its validation was determined by using confirmatory factor analysis. A total of 263 subjects were selected by systematic random sampling to represent Malaysian population for reliability and validity purposes. Results: The BM DASS-21 had very good Cronbach’s alpha values of .84, .74 and .79, respectively, for depression, anxiety and stress. In addition, it had good factor loading values for most items (.39 to .73). Correlations among scales were between .54 and .68. Conclusions: BM DASS-21 is correctly and adequately translated to Bahasa Malaysia with high psychometric properties. Further studies are required to support these findings. Key words: depression, anxiety, stress, reliability, validity, Bahasa Malaysia

Coping styles and lifestyle factors among hypertensive and non-hypertensive subjects

Introduction: The objective of this study was to investigate the relationship between hypertensive patients and their coping style and associated lifestyle factors. Methods: A total of 502 participants attending nine outpatient clinics completed the validated Bahasa Malaysia version of the Coping Inventory for Stressful Situations and sociodemographic questionnaires. The height, weight, pulse rate and blood pressure of all the participants were measured using standardised methods. Results: A total of 264 (52.6 percent) participants were hypertensive, while 238 (47.4 percent) were not. Participants with a high task-oriented score showed a significantly lower risk of hypertension compared to those with a low score (odds ratio [OR] 0.546; 95 percent confidence interval [CI] 0.371–0.804). Those with a high emotion-oriented coping score were associated with an increased risk of hypertension (OR 1.691; 95 percent CI 1.107–2.582). Hypertension was also significantly associated with a higher mean body mass index, positive family history of hypertension, history of diabetes mellitus and hypercholesterolaemia. In multiple logistic regression analysis with hypertension status as the dependent variable, a high emotion-oriented coping score, a low taskoriented coping score, age, body mass index, positive family history of hypertension and history of diabetes mellitus remain significant factors in the final model. Conclusion: These results indicated a significant relationship between hypertension and coping styles and lifestyle factors. They underscored the importance of further study as well as the development and implementation of intervention measures to improve coping skills among hypertensive patients, which may be incorporated into the management of hypertension

Design of microstrip line-coupled isosceles-triangular loop resonator antenna

In this paper, an experimental study on a microstrip line proximity coupled triangular microstrip loop resonator antenna is presented. The antenna is fed by a 50 Ω microstrip feed line arrangement at the frequency of 5.8 GHz. The antenna element is placed at λg /4 from the stub, and λg/2 away from the feed based on the voltage allocation on an open ended transmission line where λg is the guided wavelength. The antenna element was rotated 90 degree clockwise about the z-axis in parallel with the microstrip feed. This was done in order to 1) ensure a good proximity coupling, and 2) to indicate that the amount of coupling from the microstrip line to the resonator can be controlled to a certain degree by adjusting the spacing. A similar design was done without rotating the resonator, and the result is reported. It was observed that the measured |S11| of the rotated element is superior to the un-rotated by 43.75%, and 40.43% for the simulated. In all, experimental results agreed significantly with simulated results

The effect of demographics on Quality Management Principles of ISO 9001:2008 amongst Malaysia Hajj Pilgrims

The implementation of Quality Management Principles (QMP) is crucial in ensuring business excellence. Many ISO certified organizations have adopted the QMP of ISO 9001:2008 for achieving and sustaining business performance. However, studies related to the implementation of QMP amongst Malaysia Hajj pilgrims are limited. This study examines the effect of demographic of Hajj Pilgrims on QMP of ISO 9001:2008. Four constructs of QMP were developed and a questionnaire was prepared to measure the implementation of the QMP as perceived by the Malaysia Hajj Pilgrims. 500 questionnaires were distributed to the respondents using stratified random sampling procedure. A total of 350 usable questionnaires were collected and analyzed. The overall descriptive result indicated that the QMP are highly adhered to by staff of TH. It shows that the Hajj Pilgrims rated high level of QMP being practiced by the staff. This implies that TH has performed the excellent performance of QMP in the delivery of hajj services. There is no significant effect of demographic on QMP for gender, age, occupation, academic and frequency of performing Hajj except for category of Hajj pilgrims