Resource Leveling of an Industrial Building Using Genetic Algorithm Technique

Construction companies should schedule their projects in a manner that considers theefficient use of limited resources in order to complete a project within estimated budget, onschedule and in compliance with the specifications. In this context, the planning of resourcesbecomes crucial for a construction project, which can be accomplished by resource leveling.Resource leveling - also known as resource smoothing - is a method that attempts to reducethe fluctuations in resource usage in order to make the resource requirements as uniform aspossible while maintaining the original project duration. The studies dealing with resource leveling problems can be classified into two categories, which are; (1) analytical methods and(2) heuristic methods. Analytical methods may give optimal solutions on small-scaledproblems; however, they are inadequate in large-scaled problems. As a result of theweaknesses of analytical methods, many studies have been conducted in order to developmore efficient models by heuristic methods. Genetic algorithm-based resource leveling is oneof these models, which is developed to attain better solutions. The main objective of thisstudy is to handle the resource leveling problem of an industrial building using geneticalgorithms. In this context, a schedule for an industrial building is established using theCritical Path Method (CPM). The information about the logical constraints and the resourcesrequired to carry out activities were obtained through the interviews with civil engineers fromthe company, whose expertise is on industrial buildings. The proposed genetic algorithmbased resource leveling model attempts to improve the schedule. The developed modelprovided a decrease of 20% in the total resource-days required to complete the project. Thestudy is of benefit to participants of construction industry, because it makes them aware of the potential use of the combination of critical path method and genetic algorithms in order to solve the resource leveling problem

Motivation of civil engineers and architects in Turkey

Motivation is one of the key factors that stimulate individuals to improve their productivity. Therefore, motivation of construction workers has been debated with considerable interest by participants in the construction industry. However, motivating only construction workers, but ignoring the motivation of construction professionals, viz., architects and civil engineers, may not be enough to successfully complete a construction project. Although motivation of construction professionals may also enhance the performance of a construction project, this topic is mostly ignored in the motivation literature. This study attempts to fill this gap by (1) identifying the motivators that are of importance to architects and civil engineers and (2) exploring the statistical difference between architects’ and civil engineers’ motivators. For this purpose, a questionnaire survey was administered to Turkish architects and civil engineers to collect data on their perceptions of the importance of different motivators. The case of Turkey is investigated because several of the larger Turkish contractors undertake construction projects outside their home country. Statistical analysis was performed on the collected data to verify whether there are statistically significant differences in the perception of some motivators by architects and civil engineers. The study demonstrates the existence of a statistically significant difference between architects’ and civil engineers’ motivators. Identifying the architects’ and civil engineers’ motivators may help construction companies in motivating their architects and civil engineers more effectively, thus developing a quality workforce

Detecting unbalanced bids via an improved grading-based model

Unbalanced bidding, also known as skewed bidding, is the process of increasing and/or decreasing the prices of various bid items without altering the total offered bid price. Bids can be unbalanced either mathematically (front-end loading) or materially (quantity error exploitation). Owners should be very careful when evaluating the tenders as awarding a contract to an unbalanced bid may result in severe cost overruns because the prices of those items do not reflect their true costs and markup allocations. Unbalanced bidding is still a contentious issue in the construction industry. While some researchers consider it as a legal bidding strategy in such a fierce competitive business environment, others view it as an unethical practice and claim that unbalanced bids should be disqualified. Studies regarding unbalanced bidding can be categorized into two groups: (1) the ones focusing on detecting or preventing this practice to help owners; and 2) the ones focusing on optimizing unbalanced bidding to help contractors. This study aims to develop a model, which consists of eight grading systems, to assist owners in detecting materially unbalanced bids. The proposed model is the improved version of the previous model, which was composed of five grading systems. In order to demonstrate how this grading-based model can be used by owners, an illustrative example is presented. It was found that owners can easily and successfully detect unbalanced bids via the proposed mode

Impacts of different objective functions on resource leveling in construction projects: a case study

A review of the recent literature on the models that focus on resource leveling in Critical Path Method networks shows that different objective functions have been used to optimize resource utilization. The main objective of this study is to investigate the impacts of using different objective functions on resource utilization histograms in Critical Path Method networks. For this purpose, nine different resource leveling objective functions were optimized via a genetic algorithm-based model. The model was developed using actual data obtained from a steel framed industrial building construction project. It was found that each of these objective functions generates different resource utilization histograms. In order to determine the improvement levels achieved by resource leveling using nine different objective functions, the improvement percentage in each parameter and the average improvement percentage for each objective function were calculated. Even though the objective function that involves the minimization of the sum of the square of the deviations in daily resource usage provided the best average improvement percentage in the studied case, another objective function(s) may provide better average improvement percentage in different projects. The contractor should consider all objective functions for resource leveling and select the one(s) that provides the best average improvement percentage

Lower risk of hypoglycaemia and greater odds for weight loss with initiation of insulin detemir compared with insulin glargine in Turkish patients with type 2 diabetes mellitus: local results of a multinational observational study

BACKGROUND: The purpose of this analysis is to evaluate the safety and effectiveness of insulin initiation with once-daily insulin detemir (IDet) or insulin glargine (IGlar) in real-life clinical practice in Turkish patients with type 2 diabetes mellitus (T2DM). METHODS: This was a 24-week multinational observational study of insulin initiation in patients with T2DM. RESULTS: The Turkish cohort (n = 2886) included 2395 patients treated with IDet and 491 with IGlar. The change in glycosylated haemoglobin (HbA(1c)) from the pre-insulin levels was -2.21% [95% confidence interval (CI) -2.32, -2.09] in the IDet group and -1.88% [95% CI -2.17, -1.59] in the IGlar group at the final visit. The incidence rate of minor hypoglycaemia increased in both groups from the pre-insulin to the final visit (+0.66 and +2.23 events per patient year in the IDet and IGlar groups, respectively). Weight change in the IDet group was -0.23 kg [95% CI -0.49, 0.02 kg], and +1.55 kg [95% CI 1.11, 2.00 kg] in the IGlar group. Regression analysis with adjustment for previously identified confounders (age, gender, duration of diabetes, body mass index, previous history of hypoglycaemia, microvascular disease, number and change in oral anti-diabetic drug therapy, HbA(1c) at baseline and insulin dose) identified an independent effect of insulin type (IDet versus IGlar) with a risk of at least one episode of hypoglycaemia (odds ratio (OR): 0.33 [95% CI 0.21, 0.52], p <0.0001), and weight loss ≥1 kg (OR: 1.75 [95% CI 1.18, 2.59], p = 0.005), but not on HbA(1c) (+0.05% [95% CI -0.15, 0.25%], p = 0.6). CONCLUSIONS: Initiation of basal insulin analogues, IDet and IGlar, were associated with clinically significant glycaemic improvements. A lower risk of minor hypoglycaemia and greater odds of weight loss ≥1 kg was observed with IDet compared with IGlar. TRIAL REGISTRATION: NCT00825643 and NCT0074051

Nicotinamide Effects Oxidative Burst Activity of Neutrophils in Patients with Poorly Controlled Type 2 Diabetes Mellitus

Neutrophil functions are impaired in patients with diabetes mellitus. Bacterial phagocytosis and oxidative burst activity are reduced at high glucose concentrations in diabetic patients. Defects in neutrophil oxidative burst capacity are of multifactorial origin in diabetes mellitus and correlate with glucose levels. It has been reported that neutrophil NADPH oxidase activity is impaired and superoxide production is reduced in diabetic patients with or without any infections. Nicotinamide is a vitamin B3 derivative and a NAD precursor with immunomodulatory effects. In vitro studies demonstrated that nicotinamide increases NAD and NADH content of beta cells. The authors hypothesized that nicotinamide may restore the impaired oxidative burst capacity of neutrophils in diabetic patients by increasing the NADH content as an electron donor and possibly through NADPH oxidase activity of the cell. In order to test the hypothesis, this placebo-controlled and open study was designed to evaluate neutrophil functions in infection-free poorly controlled type 2 diabetic patients as compared to healthy subjects and assess the effects of nicotinamide on neutrophil phagocytosis as well as oxidative burst activity. Thirty patients with type 2 diabetes mellitus were enrolled in the study. Sixteen were females and 14 were males, with a mean age 58 ± 10. All patients were on sulphonylurea treatment and their hemoglobin A1c (HbA1c) levels were above 7.5%. The control group consisted of 10 voluntary healthy subjects. Diabetic and control subjects were not significantly different in terms of age, body mass index (BMI), leucocyte and neutrophil counts, C-reactive protein (CRP) level, and erythrocyte sedimentation rate (ESR), but HbA1c and fasting glucose levels were significantly higher in patients with diabetes mellitus. Phagocytic activity and respiratory burst indexes were measured by flow cytometric analyses as previously described by Rothe and Valet (Methods Enzyml., 233, 539–548, 1994) and compared in diabetic subjects and healthy controls. Diabetic patients were grouped to receive either 50 mg/kg oral nicotinamide (n = 15) or placebo (n = 15) for a period of 1 month. The 2 groups did not differ in terms of treatment, frequency of hypertension, BMI, diabetes duration, age, fasting plasma glucose (FPG), HbA1c, CRP, ESR, polymorphonuclear leukocyte (PNL) and neutrophil counts. Neutrophil functions were reassessed after the treatment period. Phagocytic activity represented as indexes were lower in diabetic patients when compared to healthy subjects, but the differences were not statistically significant (P > .05). Patients with diabetes mellitus had significantly lower oxidative burst indexes when compared to healthy controls (P values < .05). In diabetic patients, a negative correlation between neutrophil functions and HbA1c was found which was not statistically significant (P values > .05). Phagocytic indexes were similar in nicotinamide and placebo groups after treatment period (P > .05). But oxidative burst activity in patients receiving nicotinamide was greater when compared with placebo and the difference was statistically significant at 30 and 45 minutes (P values .04 and .03). This effect of nicotinamide may be due to increased NADH content and NADPH oxidase activity of the cell, which needs to be further studied. Impaired neutrophil functions may aggravate various infections in patients with diabetes mellitus and blood glucose regulation is an important target of treatment to improve neutrophil functions. But nicotinamide treatment may help to improve prognosis in diabetic patients with severe infections

The Hazar pull-apart along the East Anatolian Fault: Structure and active deformation

Understanding the irregularity of seismic cycles: A case study in Turke