This paper presents a comparative performance analysis of some metaheuristics such as the African Buffalo Optimization algorithm (ABO), Improved Extremal Optimization (IEO), Model-Induced Max-Min Ant Colony Optimization (MIMM-ACO), Max-Min Ant System (MMAS), Cooperative Genetic Ant System (CGAS), and the heuristic, Randomized Insertion Algorithm (RAI) to solve the asymmetric Travelling Salesman Problem (ATSP). Quite unlike the symmetric Travelling Salesman Problem, there is a paucity of research studies on the asymmetric counterpart. This is quite disturbing because most real-life applications are actually asymmetric in nature. These six algorithms were chosen for their performance comparison because they have posted some of the best results in literature and they employ different search schemes in attempting solutions to the ATSP. The comparative algorithms in this study employ different techniques in their search for solutions to ATSP: the African Buffalo Optimization employs the modified Karp-Steele mechanism, Model-Induced Max-Min Ant Colony Optimization (MIMM-ACO) employs the path construction with patching technique, Cooperative Genetic Ant System uses natural selection and ordering; Randomized Insertion Algorithm uses the random insertion approach, and the Improved Extremal Optimization uses the grid search strategy. After a number of experiments on the popular but difficult 15 out of the 19 ATSP instances in TSPLIB, the results show that the African Buffalo Optimization algorithm slightly outperformed the other algorithms in obtaining the optimal results and at a much faster speed.
This paper presents the data description of the African buffalo optimization algorithm (ABO). ABO is a recently-designed optimization algorithm that is inspired by the migrant behaviour of African buffalos in the vast African landscape. Organizing their large herds that could be over a thousand buffalos using just two principal sounds, the /maaa/ and the /waaa/ calls present a good foundation for the development of an optimization algorithm. Since elaborate descriptions of the manual workings of optimization algorithms are rare in literature, this paper aims at solving this problem, hence it is our main contribution. It is our belief that elaborate manual description of the workings of optimization algorithms make it user-friendly and encourage reproducibility of the experimental procedures performed using this algorithm. Again, our ability to describe the algorithm's basic flow, stochastic and data generation processes in a language so simple that any non-expert can appreciate and use as well as the practical implementation of the popular benchmark Rosenbrock and Shekel Foxhole functions with the novel algorithm will assist the research community in benefiting maximally from the contributions of this novel algorithm. Finally, benchmarking the good experimental output of the ABO with those of the popular, highly effective and efficient Cuckoo Search and Flower Pollination Algorithm underscores the ABO as a worthy contribution to the existing body of population-based optimization algorithms.
OBJECTIVE: This study aims to determine the relationships between behavioural and psychological symptoms of dementia (BPSD), cognitive impairment and burden of care of patients with dementia.
METHOD: A cross-sectional, non-randomised study of 65 elderly patients with dementia and their caregivers was conducted over a 3-month period in January 2007 at the memory clinics of Universiti Kebangsaan Malaysia Medical Centre and Hospital Kuala Lumpur. Patients' cognitive functions were assessed with the Mini Mental State Examination (MMSE). Caregivers were interviewed to determine the severity of BPSD and caregiver burden (CB) using the Neuropsychiatric Inventory (NPI) Questionnaire and Zarit Burden Interview (BI) respectively.
RESULTS: Cognitive impairment did not contribute significantly to CB. Multiple linear regression analysis showed that high BPSD scores contributed 0.27 more in BI score, female patients contributed 0.37 less in BI score and caregivers with higher educational level contribute 0.5 more in BI score.
CONCLUSION: Patients' BPSD and male gender, but not cognitive impairment, were associated with CB. Even though CB was experienced more among caregivers with better education, all caregivers should be screened to ensure their general well-being.
KEYWORDS: BPSD; Caregiver burden; Cognitive impairment
Study site: Memory clinics, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM) and Hospital Kuala Lumpur, Kuala Lumpur, Malaysia
Nutrition surveys based on a representative sample of the Malaysian adult population have hitherto not been reported. In 2003, the Ministry of Health, Malaysia, conducted the Malaysian Adult Nutrition Survey (MANS), the first and largest nutrition survey in the country which aimed to provide detailed quantitative information on nutritional status, food and nutrient intakes, and physical activity pattern on a nationwide representative sample of adult subjects between the ages of 18 and 59 years. The survey covered four zones in Peninsular Malaysia (Central, Southern, Northern and East Coast), Sabah and Sarawak. This paper presents the mean and selected percentiles of energy and nutrient intake of 6886 subjects by selected demographic and socioeconomic characteristics. Energy contributions by macronutrients and dietary adequacy in relation to the Recommended Nutrient Intake for Malaysians are also described. Information on dietary intake was collected by trained nutritionists using a one day 24-hour diet recall. Dietary data were analysed using Nutritionist Pro, a diet analysis software and statistical analysis was carried out using the SPSS ver. 13.0. In most of the demographic and socioeconomic groups, males had higher mean energy (1776 kcal) and nutrient intake and percent achievement of RNI than females (1447 kcal). The proportions of calories derived from macronutrients were within the recommendations for a healthy diet. Intake of micronutrients such as iron, calcium and vitamin A was about 50% of RNI particularly in women. Sodium intake of Malaysians, not reported in earlier studies, is also made available. Under-reporting using the EI/BMR ratio was found in half of the population studied. The present study provides the first national estimates of energy and nutrient intake of the Malaysian adult population. Regular nutrition surveys are needed at the national level to provide valuable information on trends in food and nutrient intake, particularly among age and ethnically diverse subgroups of the population.
Study name: Malaysian Adult Nutrition Survey (MANS-2003)
Meal and snack patterns are associated with energy and nutrient intakes and consequently health and nutritional status. The aim of this paper is to describe the percentage of daily energy intake from meals and afternoon snack among Malaysian adults. The study included a representative sample of adults aged 18-59 years (n=7349) from a nationwide Food Consumption Survey conducted by the Ministry of Health. Information on dietary intake was obtained using a one day 24-hour diet recall (24-HDR). Dietary data on 6886 adults were analysed using Nutritionist ProTM and statistical analysis was carried out using the SPSS 13.0. The median percentage of daily energy intake is reported only for adults consuming meals and afternoon tea and by socio-demographic characteristics as well as body mass index (BMI) status. More than 80% of Malaysian adults consumed morning meals, lunch and dinner and 54% reported having afternoon tea. The median percentage of energy intake from morning meals, lunch, dinner and afternoon tea was 29.9%, 30.5%, 32.4% and 17%, respectively. There were variations in the median percentage of energy from meals and snacks according to the socio-demographic variables and BMI status. It is important to understand the eating patterns of Malaysians as the information can assist in efforts to address obesity and diet-related chronic diseases among adults.
Study name: Malaysian Adults Nutrition Survey (MANS-2003)