A reduced-order extended state observer (RESO) based a continuous sliding mode control (SMC) is proposed in this paper for the tracking problem of high order Brunovsky systems with the existence of external perturbations and system uncertainties. For this purpose, a composite control is constituted by two consecutive steps. First, the reduced-order ESO (RESO) technique is designed to estimate unknown system states and total disturbance without estimating an available state. Second, the continuous SMC law is designed based on the estimations supplied by the RESO estimator in order to govern the nominal system part. More importantly, the robustness performance is well achieved by compensating not only the lumped disturbance, but also its estimation error. Finally, the tracking performance is examined by carrying out several simulations on robotic systems with compliant actuators as an application example of the high order systems. In addition, the comparative study is conducted between the proposed SMC method with RESO and a feedback linearization control (FLC) with a full-order ESO to confirm the estimation and tracking performance of the proposed scheme.
Now-a-days the Flexible AC Transmission Systems (FACTS) technology is very effective in improving the power flow along the transmission lines and makes the power system more flexible and controllable. This paper deals with the most robust type of FACTS devices; it’s a Unified Power Flow Controller (UPFC). Many cases have been taken to study how the system behaves in the presence and absence of the UPFC under normal and contingency conditions. The UPFC is a device that can be used to improve the bus voltage, increasing the loadability of the line and reduce the active and reactive power losses in the transmission lines, through controlling the flow of real and reactive power. Both the magnitude and the phase angle of th
... Show MoreAlthough rare, coarctation of aorta is a treatable cause of hypertension, transcatheter dilatation by balloon with or without stent are a well-known treatment strategy
Uranium concentration was estimated in urine samples of three age groups, G1≤ 30 years, n=28, G2 age range of 31-40 years, n=28, and G3 of age > 40 years, n=32, using two types of detectors CR-39 and LR-115 solid-state nuclear track detector (SSNTD) for results comparison.
Results showed that uranium mean level values for CR-39 were 1.961 ±0.08 µg/L, 1.810 ±0.09 µg/L and 1.814 ±0.076 µg/L for G1, G2 and G3 respectively, while the mean values of uranium concentration using LR-115 were 0.972 ±0.07 µg/L, 0.922 ±0.07 µg/L and 1.018 ±0.08 µg/L in G1, G2 and G3 respectively, with significant statistical difference betw
... Show MoreThe ground state charge, neutron and matter densities for two-neutron halo nuclei P
12
PBe
and P
14
PBe are calculated within a two- frequency shell model approach. In the description of
the halo nuclei it is important to take into account a model space for P
10
PBe and P
12
PBe different
from the two halo neutrons which have to be treated separately in order to explain their
properties. The structures of the halo P
12
PBe and P
14
PBe nuclei show that the dominant
configurations when the two halo neutrons distributed over the 1d shell orbits. Elastic
Coulomb scattering form factors of these two exotic nuclei are also studied through the
combination of the density distributions of
This paper aims to verify the existence of relationships between product innovation and the reputation of the organization. The study problem is that the State Organization for Marketing of Oil (SOMO) system is inflexible in terms of marketing procedures and needs innovative, unconventional methods in innovating its products and improving performance. The reputation of the organization. The importance of the study lies in that it is an attempt to raise the interest of SOMO in its approach to the research variables in order to enhance its competitive position in the future and improve the marketing business environment, which contributes to enhancing the reputation of the organization by product innovation. The study sample
... Show MoreThis study aims at defining the concept of the fragile state, a term that came into existence in 2014, when the states that had internal Problems and external interventions were referred to as the failure states. However, the indicators for their designation and the criteria adopted are 12 indicators that address all aspects of the State’s duties vis-a-vis its citizens. The study examined the reasons that led to the continuation of Iraq within the fragile states, and the selection of the five years within the time limits of the study due to the factors that led to the decline of Iraq and falling back within the most fragile countries. The study dealt with the fragile state challenges to the media reality as a result of the change of it
... Show MoreGroundwater is an essential source because of its high quality and continuous availability characterize this water resource. Therefore, the study of groundwater has required more attention. The present study aims to assess and manage groundwater quality's suitability for various purposes through the Geographical Information System GIS and the Water Quality Index WQI. The study area is located in the city of Baghdad in central Iraq, with an approximate area of 900 , data were collected from the relevant official departments representing the locations of 97 wells of groundwater in the study area for the year 2019, as it included physicochemical parameters such as pH, EC, TDS, Na, K, Mg, Ca, Cl, , and &nbs
... Show MoreThere has been a growing interest in the use of chaotic techniques for enabling secure communication in recent years. This need has been motivated by the emergence of a number of wireless services which require the channel to provide low bit error rates (BER) along with information security. The aim of such activity is to steal or distort the information being conveyed. Optical Wireless Systems (basically Free Space Optic Systems, FSO) are no exception to this trend. Thus, there is an urgent necessity to design techniques that can secure privileged information against unauthorized eavesdroppers while simultaneously protecting information against channel-induced perturbations and errors. Conventional cryptographic techniques are not designed
... Show MoreA simple setup of random number generator is proposed. The random number generation is based on the shot-noise fluctuations in a p-i-n photodiode. These fluctuations that are defined as shot noise are based on a stationary random process whose statistical properties reflect Poisson statistics associated with photon streams. It has its origin in the quantum nature of light and it is related to vacuum fluctuations. Two photodiodes were used and their shot noise fluctuations were subtracted. The difference was applied to a comparator to obtain the random sequence.