despite the role of oral corticosteroids in management of sever asthma, use of these drugs needs careful awareness of its many side effects. there are controversies about the role of methotrexate in lowering the need for corticosteroides in these patients. in this study an attempt has been made to determine methotrexate effects in corticosteroid dependent asthma. six patients were entered in a ...

background  & aim: case-crossover  studies are the case-control  version of crossover studies. in these studies, cases and controls are the same subjects. the term crossover is applied for designs that all subjects pass through both treatment (exposure) and placebo (non-exposure) phases. in fact they are  crossover  of  subjects  between  periods  of  exposure  and  non-exposure.  this  design ...

abstract background: menthol is the most important active material in mint and different mechanisms have been suggested for the way mint functions, most of which emphasize its analgesic effect owing to the presence of a group of temporary protein receptors. this study investigates the efficacy of peppermint capsule in the treatment of primary dysmenorrhea, in comparison with mefenamic acid and ...

the thermodynamic properties of fluids can be predicted using the global equations of state. among these thermodynamic properties of fluids, we choose the densities of the liquid and vapor phases. this paper considers the application of the crossover model to the vapor-liquid rectilinear diameter of sulfurhexafluoride. we also present a comparison of the crossover model equation with the experi...

Uniform crossover for binary strings has a natural geometric interpretation that allows us to generalize it rigorously to any search space endowed with a notion of distance and any representation [6]. In this paper, we present an analogous characterization for one-point crossover and explicitly derive formally specific one-point crossovers for a number of well-known representations.

Crossover operator plays a crucial role in the efficiency of genetic algorithm (GA). Several crossover operators have been proposed for solving the travelling salesman problem (TSP) in the literature. These operators have paid less attention to the characteristics of the traveling salesman problem, and majority of these operators can only generate feasible solutions. In this paper, a crossover ...

real coded genetic algorithm, rcga, is the type of ga which operates on chromosomes with real valued parameters. different mutation and crossover operations are defined for rcga. one usable crossover for this kind of ga is to consider its chromosomes simply as bit strings and utilize the same operations as binary coded ga. in this paper, we attempt to show that this kind of crossover can not ha...

This paper studies the nonlinear optimization problems subject to bipolar max-min fuzzy relation equation constraints. The feasible solution set of the problems is non-convex, in a general case. Therefore, conventional nonlinear optimization methods cannot be ideal for resolution of such problems. Hence, a Genetic Algorithm (GA) is proposed to find their optimal solution. This algorithm uses th...

سخن سردبیر Editorial مجله دانشگاه علوم پزشکی رفسنجان دوره هجدهم، شهریور 1398، 513-514     مطالعات مورد – همگذری (Case Crossover Studies)   محسن رضائیان[1]   M. Rezaeian   مطالعات مورد - همگذری (Case Crossover Studies) به ویژه برای مشخص کردن تأثیر زودگذر مواجهه بر روی رخداد یک بیماری حاد، مناسب است. در این طراحی، به جای آن‌که یک گروه مجزا برای کنترل انتخاب  شود، هر مورد در نقش کنترل ...