stand establishment in crusting soil is one of the main concerns in the production of crops with delicate seedlings such as cotton, onions and rape seed. crust breaking, maintaining soil moisture and adding chemical and organic amendments to soil are different methods to weaken soil strength and allow the shoots to emerge. these methods are not always successful because they depend on factors s...

breaking bad news is one of the most burdensome tasks physicians face in their everyday practice. it becomes even more challenging in the context of hiv + patients because of stigma and discrimination. the aim of the current study is to evaluate the quality of giving hiv seroconversion news according to spikes protocol. numbers of 154 consecutive hiv + patients from imam khomeini hospital testi...

pressurized irrigation technologies of course have the potential to raise the productivity of land and water; but, these technologies could not popularize among the smallholders who own millions of farms worldwide. in developing pressurized irrigation technologies, particularly for field crops irrigation, researchers and manufacturers have developed more specialized and expensive technologies w...

In this paper we address symmetry on combinatorial problems by following the approach of imposing additional symmetry-breaking constraints. Differently from other works in the literature, we attack the problem at the specification level. In fact, sometimes symmetries on specifications can be very easily detected, and symmetry-breaking formulae generated. We give formal definitions of symmetries...

Many constraint problems exhibit dominance relations which can be exploited for dramatic reductions in search space. Dominance relations are a generalization of symmetry and conditional symmetry. However, unlike symmetry breaking which is relatively well studied, dominance breaking techniques are not very well understood and are not commonly applied. In this paper, we present formal definitions...

The surfactant-polymer-based (S/P) fracturing fluid combines the advantages of surfactant-based and polymer-based fluids. In this study, synergistic tackifying cationic surfactants carboxymethyl hydroxyethyl cellulose potential application in hydraulic was investigated. Firstly, cetyltrimethylammonium chloride (CTAC) salicylic acid (SA) with a weight ratio 4:1 were optimized as main agent small...

Dormancy breaking and germination requirements were investigated in seeds of Ferula ovina and Ferula gummosa. Seeds of rather species were collected from north and eastern-north rangelands of Iran. Seeds of each of the species were subjected to different treatments including various levels of GA3, chilling and combination of GA3 and chilling (GA-chilling). In contrast to treated seeds, non-trea...

This paper introduces six ways for handling a chain of lexicographic ordering constraint between the origins of identical orthotopes (e.g., rectangles, boxes, hyper-rectangles) subject to the fact that they should not pairwise overlap. While the first two ways deal with the integration of a chain of lexicographic ordering constraint within a generic geometric constraint kernel, the four latter ...

Symmetry is an important feature of many constraint programs. We show that any problem symmetry acting on a set of symmetry breaking constraints can be used to break symmetry. Different symmetries pick out different solutions in each symmetry class. This simple but powerful idea can be used in a number of different ways. We describe one application within model restarts, a search technique desi...