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This paper presents a novel estimation method for coarse alignment of a marine strapdown inertial navigation system (SINS) under mooring conditions. The properties of gravitational motion are used to improve the accuracy of coarse alignment. The parametric motion of gravitational apparent is a circle that is on the surface of a sphere. The location of this parametric circle is dependent on the definition of the reference frames and the initial angles of SINS. In the method proposed here the initial direct cosine matrix is calculated only from the location of the gravity motion parametric circle. The novelty of this paper is to provide a new method for estimating the gravity motion trajectory in inertial frame, as well as direct extraction of the initial direct cosine matrix from this estimated trajectory. Simulation and testing show that the proposed method is suitable for coarse alignment in mooring conditions.

In this paper, a novel algorithm of weighted k-means clustering with geodesic criteria is presented to generate a uniform database for a star sensor. For this purpose, selecting the appropriate star catalogue and desirable minimum magnitude and eliminating double stars are among the steps of the uniformity process. Further, Delaunay triangulation and determining the scattered data density by using a Voronoi diagram were used to solve the problems of the proposed clustering method. Thus, by running a Monte Carlo simulation to count the number of stars observed in different fields of view, it was found that the uniformity leads to a significant reduction of the probability of observing a large number of stars in all fields of view. In contrast, the uniformity slightly increased the field of view needed to observe the minimum number of required stars for an identification algorithm.

This paper focuses on the trajectory planning for a UAV on a low altitude terrain following/threat avoidance (TF/TA) mission. Using a grid-based approximated discretisation scheme, the continuous constrained optimisation problem into a search problem is transformed over a finite network. A variant of the Minimum Cost Network Flow (MCNF) to this problem is then applied. Based on using the Digital Terrain Elevation Data (DTED) and discrete dynamic equations of motion, the four-dimensional (4D) trajectory (three spatial and one time dimensions) from a starting point to an end point is obtained by minimising a cost function subject to dynamic and mission constraints of the UAV. For each arc in the grid, a cost function is considered as the combination of the arc length, fuel consumption and flight time. The proposed algorithm which considers dynamic and altitude constraints of the UAV explicitly is then used to obtain the feasible trajectory. The resultant trajectory can increase the survivability of the UAV using the threat region avoidance and the terrain masking effect. After obtaining the feasible trajectory, an improved algorithm is proposed to smooth the trajectory. The numeric results are presented to verify the capability of the proposed approach to generate admissible trajectory in minimum possible time in comparison to the previous works.

Whole soybean (SB) is used as a high energy-protein supplement for dairy cows, but the protein is highly degradable by rumen microbes. Various chemical and physical processing has been suggested to decrease ruminal protein degradability, that heat processing is the most commonly used physical method. Modern systems for protein evaluations in ruminants are moving in the direction of predicting absorption of amino acids from the small intestine, so the determination of intestinal digestibility of amino acids is of special importance particularly in heat-treated feedstuffs. The objective of this research was to elucidate the effects of roasting and steep-roasting on ruminal and post-ruminal disappearance of essential and non-essential amino acids (EAA and NEAA) of Iranian SB.

In Iran, East Azerbaijan province is one of the most important farm animal production area and feedstuffs such as wheat grain (WG) and wheat bran (WB) together with alfalfa hay, barley grain, and wheat straw are the most common ingredients of animal rations. In recent years, production of WG and its main by-product, WB, have considerably been increased. Organic matter and mineral contents of WG in a given area can be influenced markedly by climate, soil and fertilizer treatments, growth stage and agronomic factors. Nutrient composition of WB also depends on variety of WG and mill processing conditions. Therefore, it is necessary to determine the nutrient composition of WG and WB to use in formulating balanced rations. The objective of present study was to determine nutrient composition of WG and WB in East Azerbaijan.

Feed costs account for large part of the total costs in milk production. Thus, dairy producers attempt to minimize the costs of feeding their herds particularly when milk prices are low. By-product feeds such as soybean hulls, In addition to the potential of providing an economical alternative, can be successfully used as a source of fiber in rations for dairy cattle when forages have poor quality or are in short supply (Firkins, 1997; Weidner and Grant, 1994). Alternatively, replacing cereal grains with SH in diets for dairy cows may contribute to elevated intakes of energy while preventing a disruption of rumen functionality (Ipharraguerre et al., 2003). The objectives of this paper are to evaluate effects of soybean hulls in replacement of alfalfa hay, corn silage and wheat bran on performance and total tract apparent nutrients digestibility.

The in situ technique forms the basis of many feed evaluation systems for ruminants. Although this method is widely used, the NBT is very laborious, time-consuming, and incubations and analyses of the feed residues often last several weeks. Therefore, several other techniques have been investigated to measure and predict ruminal degradation of various chemical components of feedstuffs. The aim of this study is to investigate the possibilities of estimating in situ degradation characteristics of DM, CP, ADF and NDF in several feedstuffs by gas production characteristics and chemical composition.