background and objectives: the quefts model is using for optimizing fertilizer managements in crops, but it has not been used in iran yet. quefts accounts for interactions among npk affecting the ie of n, p and k and allows differentiation according to different yield levels targeted. it is necessary to determine crops parameters before application the model in the studying area. the first step...

Natural forests in the humid tropics differ from temperate and plantation forests in several ways: there may be many tree species; many of these may occur infrequently; there may be a large range of tree sizes and shapes present; tree ages may be unknown and indeterminate; and despite the luxuriant appearance some rainforests, growth rates may be relatively low. This has many implications for t...

Today, incorrect use of lands and land use changes, excessive grazing, no suitable using of agricultural farms, plowing on steep slopes, road construct, building construct, mine excavation etc have been caused increasing of soil erosion and sediment yield. For erosion and sediment estimation one can use statistical and empirical methods. This needs to identify land unit map and the map of effec...

ABSTRACT- Crop rotation has many benefits for agro-ecosystems production. In order to evaluate two current rotation systems of wheat (Triticum aestivum L.) production in Kamalabad region of Fasa, an experiment was conducted during 2015-2016 growing season. The rotation systems were fallow-wheat and cotton (Gossypium spp.)-wheat. Research plots were arranged as a randomized complete block design...

Plane-wave DOA estimation techniques yield biased estimates of source bearing angles in the ocean due to the multimode nature of acoustic propagation in an oceanic waveguide. Bearing estimation using matched 5eld processing requires either a computationally expensive three-dimensional search or a priori knowledge of the source ranges and depths. A new subspace-based high-resolution bearing esti...

Accurate estimation of software development effort is a very difficult job.Both under estimation as well as over estimation can lead to serious consequences. So its very important to find a technique which can yield accurate results for software effort estimation. Here in our paper we have evaluated various machine learning techniques for software effort estimation like bagging, decision trees,...

Quantitative polymerase chain reaction (qPCR) has been widely used to quantify changes in gene copy numbers after radiation exposure. Here, we show that gamma irradiation ranging from 10 to 100 Gy of cells and cell-free DNA samples significantly affects the measured qPCR yield, due to radiation-induced fragmentation of the DNA template and, therefore, introduces errors into the estimation of ge...

The article introduces an integrated market-segmentation and tourism yield estimation framework for inbound tourism. Conventional approaches to yield estimation based on country of origin segmentation and total expenditure comparisons do not provide sufficient detail, especially for mature destinations dominated by large single-country source markets. By employing different segmentation approac...

The level of yield risk faced by a farmer is an important factor in the design of appropriate management and insurance strategies. The difference between field scale and regional scale yield risk, which can be significant, also represents an important measure of the factors that cause the yield gap – the difference between average and maximum yields. While field scale yield risk is difficult to...