Let A and B be n × m matrices. The matrix B is said to be g-row majorized (respectively g-column majorized) by A, if every row (respectively column) of B, is g-majorized by the corresponding row (respectively column) of A. In this paper all kinds of g-majorization are studied on Mn,m, and the possible structure of their linear preservers will be found. Also all linear operators T : Mn,m ---> Mn...

The purpose of this research is to study the effect deep loosening row spacings on physical properties soil and yield organic potatoes. Two variants cultivation were used in spacings: usual 25 cm deep. was carried out with a row-crop chisel cultivator. Its design developed at institute. Analysis data obtained as result experimental studies showed that had positive compaction both inter-row widt...

Long-term research aimed to determine whether narrow row spacing and harvest weed seed destruction, in combination with herbicide use, would be sufficient to drive a Lolium rigidum population to extinction. A trial was run from 1987 to 2013, with treatments including crop row spacings of 9, 18, 27 or 36 cm and crop residue burning or retention. Herbicides were applied to reflect regional practi...

A study was conducted to check the effect of different sowing dates and row spacing on the growth, seed yield and quality of offseason pea (Pisum sativum L. cv. Climax). Significant differences were recorded among sowing dates for days to germination while nonsignificant results were found for row spacing and interaction (A × B). Maximum days to germination were recorded in D1 (20 th April) and...

A field experiment was conducted for two consecutive years (2003 and 2004) to study the effect of row spacing (75, 65 and 55cm) and different weed competition durations (0, 15,30,45,60 days after emergence and throughout the growth period) on weeds density and biomass and growth and yield of maize. Reducing row spacing significantly suppressed the weed density and biomass. The maximum reduction...

This work was aimed at assessing whether in silage maize it is possible to replace precisionplanting with a volumetric seeding in the perspective of developing hybrid machines to strip tilland sow both high density crops like winter cereals and low density crops like maize. This inorder to reduce the number of machines in the farm, simplify logistics and reduce amortizationcosts. Two experiment...

purpose: e is a commonly use letter for illiterates or those who could not read english to measure visual acuity. the e chart is the mainly used charts in iran. however, they do not have the standards. they are in different format, fixed for 6 meter test, with or without lighting, with unequal number of letters in each line and different contrasts. as a result, there is an essential need for a ...

potato (solanum tuberosum l.) cultivation in two different climates causes difference in its growth process.the most frequently used indicators of growth for plants are the tuber growth rate (tgr), crop growth rate (cgr) and leaf area index (lai). shoot dry weight is the easiest, quickest and least costly component to measure the competitive features of plants.the results of some studies showed...