Ground-based active optical sensors (GBAOS) have been successfully used in agriculture to predict crop yield potential (YP) early in the season and to improvise N rates for optimal crop yield. However, the models were found weak or inconsistent due to environmental variation especially rainfall. The objectives of the study were to evaluate if GBAOS could predict YP across multiple locations, soil types, cultivation systems, and rainfall differences. This study was carried from 2011 to 2013 on corn (Zea mays L.) in North Dakota, and in 2017 in potatoes in Maine. Six N rates were used on 50 sites in North Dakota and 12 N rates on two sites, one dryland and one irrigated, in Maine. Two active GBAOS used for this study were GreenSeeker and Holland Scientific Crop Circle Sensor ACS 470 (HSCCACS-470) and 430 (HSCCACS-430). Rainfall data, with or without including crop height, improved the YP models in term of reliability and consistency. The polynomial model was relatively better compared to the exponential model. A significant difference in the relationship between sensor reading multiplied by rainfall data and crop yield was observed in terms of soil type, clay and medium textured, and cultivation system, conventional and no-till, respectively, in the North Dakota corn study. The two potato sites in Maine, irrigated and dryland, performed differently in terms of total yield and rainfall data helped to improve sensor YP models. In conclusion, this study strongly advocates the use of rainfall data while using sensor-based N calculator algorithms.
Cooperation spectrum sensing in cognitive radio networks has an analogy to a distributed decision in wireless sensor networks, where each sensor make local decision and those decision result are reported to a fusion center to give the final decision according to some fusion rules. In this paper the performance of cooperative spectrum sensing examines using new optimization strategy to find optimal weight and threshold curves that enables each secondary user senses the spectrum environment independently according to a floating threshold with respect to his local environment. Our proposed approach depends on proving the convexity of the famous optimization problem in cooperative spectrum sensing that stated maximizing the probability of detec
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In this paper, we proposed a new class of weighted Rayleigh distribution based on two parameters, scale and shape parameters which are introduced in Rayleigh distribution. The main properties of this class are investigated and derived.
The tourism services provided in the hotel organizations are a set of material and moral elements that represent tourist attractions that are offered to the guests in order to satisfy their needs and desires are accommodation, food, drink and other facilities to reach the satisfaction and satisfaction of guests.Where these tourist services need a mechanism to ensure their quality by working to identify and calculate the costs of these services properly and accurately with the attempt to referendum and reduce the waste and loss to reduce these costs while providing the finest types of tourism services by calculating the cost of production and the administration seeks to reduce Non-essential activities through hotel activities that add val
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Through this study, the following has been proven, if is an algebraically paranormal operator acting on separable Hilbert space, then satisfies the ( ) property and is also satisfies the ( ) property for all . These results are also achieved for ( ) property. In addition, we prove that for a polaroid operator with finite ascent then after the property ( ) holds for for all.
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This research aims to identify the vigilant personality of University teachers in term of gender. To this end, the researcher used the scale of Al-tememe (2017) for the vigilant personality, the scale was administered to the sample of the study which was (100) male and female teachers. The results have shown that university teachers generally have a vigilant personality, as well as the result showed a difference between male and female teachers on the level of vigilant personality in favor of males. In the light of these results the researcher has come with a number of recommendations and suggestions.
A Bayesian formulation of the ridge regression problem is considerd, which derives from a direct specification of prior informations about parameters of general linear regression model when data suffer from a high degree of multicollinearity.A new approach for deriving the conventional estimator for the ridge parameter proposed by Hoerl and Kennard (1970) as well as Bayesian estimator are presented. A numerical example is studied in order to compare the performance of these estimators.
Brachycerous Dipteran species on alfalfa plant Medicago sativa surveyed in several regions of Iraq from March to November 2012. The study was registered 14 species belonging to nine genera and four families. The results showed that Limnophra quaterna, Atherigona laevigata and Atherigona theodori as new records to Iraq and new pests of alfalfa.