Trajectory tracking and vibration suppression are essential objectives in a flexible joint manipulator control. The flexible joint manipulator is an under-actuated system, in which the number of control actions is less than the degree of freedom to be controlled. It is very challenging to control the underactuated nonlinear system with two degree of freedom. This paper presents a hierarchical sliding mode control (HSMC) for a rotary flexible joint manipulator (RFJM). Firstly, the rotary flexible joint manipulator is modeled by two subsystems. Secondly, the sliding surfaces for both subsystems are constructed. Finally, the control action is designed based on the Lyapunov function. Computer simulation results demonstrate the effectiveness of the proposed control. The comparative study shows the proposed method has superior performance than the conventional sliding mode control by achieving the controlled objectives such as a satisfactory tracking performance and an acceptable vibration reduction for the single link flexible joint robot manipulator.
In their growth stages, cities become an aggregation of different urban contexts as a result of development or investment projects with other goals, which creates urban tension at several levels. Previous studies presented different approaches and methods to address specific aspects of urban stress, and thus contemporary visions and propositions varied, which required a field for research. The research, from a review of the proposals, the research problem emerged in need to study the indicators and trends of balanced urban development that address the tensions between different social, economic and urban contexts". Accordingly, the objective of the research is determined as "Building a comprehe
... Show MoreIn this research, a factorial experiment (4*4) was studied, applied in a completely random block design, with a size of observations, where the design of experiments is used to study the effect of transactions on experimental units and thus obtain data representing experiment observations that The difference in the application of these transactions under different environmental and experimental conditions It causes noise that affects the observation value and thus an increase in the mean square error of the experiment, and to reduce this noise, multiple wavelet reduction was used as a filter for the observations by suggesting an improved threshold that takes into account the different transformation levels based on the logarithm of the b
... Show MoreA field experiment was conducted on the form of the Dept. of Field Crop Sci. / College of Agriculture / University of Baghdad in spring and fall seasons of 2009 and 2010 . Ten inbreds of maize were planted and crossed to each other to produce single crosses . In the second season, single crosses were planted along with thin parent to produce three – way and double crosses . In the third seasons panet and crosses were planted . Crosses were selfed to produce F2 seeds and increase seeds of inbreds . In the fourth season, all grin types were planted , and their agronomic traits were evaluated . Values of P of inbreds , F1 and F2 were calculated for agronomic traits . The new formula to predict inbreeding depression ( ID ) F2 plant without gr
... Show MoreTraditional accounting takes only one dimension (economic) in calculating the value added of the company, and all other aspects (including environmental and social) are neglected, and despite the emergence of Sustainability Accounting and the interest of companies in preparing sustainability reports, these reports are suffering from many problems, including multiple metrics used in measuring companies (cash, quantity and lavish). In addition, these reports may reach dozens of pages in some companies and this causes the problem (information overload) which affects the qualitative properties of accounting information such as appropriate and relative, which requires the need to find a tool that can measure the Sustainability Unit of
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People are supposed to use language harmoniously and compatibly. However, aggression may characterize much of human communication. Aggression has long been recognized as a negative anti-social issue that prevails in most personal interactions. If it abounds in familial communications, it is more dangerous due to its harmful effects on individuals, and consequently on societies. Aggression refers to all the instances in which we try to get our way without any consideration for others. Moriarty’s novel (2014), Big Little Lies, is argued to represent the patterns of aggressive communications. This study aims to find out the motivations behind aggressive language in familial communication in this
... Show MoreTraditionally, path selection within routing is formulated as a shortest path optimization problem. The objective function for optimization could be any one variety of parameters such as number of hops, delay, cost...etc. The problem of least cost delay constraint routing is studied in this paper since delay constraint is very common requirement of many multimedia applications and cost minimization captures the need to
distribute the network. So an iterative algorithm is proposed in this paper to solve this problem. It is appeared from the results of applying this algorithm that it gave the optimal path (optimal solution) from among multiple feasible paths (feasible solutions).
The migration from IPv4 to IPv6 can not be achieved in a brief period, thus both protocols co-exist at certain years. IETF Next Generation Transition Working Group (NGtrans) developed IPv4/IPv6 transition mechanisms. Since Iraq infrastructure, including universities, companies and institutions still use IPv4 protocol only. This research article tries to highlight, discuss a required transition roadmap and extend the local knowledge and practice on IPv6. Also, it introduces a prototype model using Packet tracer (network simulator) deployed for the design and implementation of IPv6 migration. Finally, it compares and evaluates the performance of IPv6, IPv4 and dual stack using OPNET based on QoS metrics such as throughput, delay and point to
... Show MoreThe utilization of sugarcane molasses (SCM), a byproduct of sugar refining, offers a promising bio-based alternative to conventional chemical admixtures in cementitious systems. This study investigates the effects of SCM at five dosage levels, 0.25%, 0.50%, 0.75%, 1.00%, and 1.25% by weight of cement, on cement mortar performance across fresh, mechanical, thermal, durability, and density criteria. A comprehensive experimental methodology was employed, including flow table testing, compressive strength (7, 14, and 28 days) and flexural strength measurements, embedded thermal sensors for real-time hydration monitoring, water absorption and chloride ion penetration tests, as well as 28-day density determination. Results revealed clear
... Show MoreAn experimental study was performed to estimate the forced convection heat transfer performance and the pressure drop of a single layer graphene (GNPs) based DI-water nanofluid in a circular tube under a laminar flow and a uniform heat flux boundary conditions. The viscosity and thermal conductivity of nanofluid at weight concentrations of (0.1 to 1 wt%) were measured. The effects of the velocity of flow, heat flux and nanoparticle weight concentrations on the enhancement of the heat transfer are examined. The Nusselt number of the GNPs nanofluid was enhanced as the heat flux and the velocity of flow rate increased, and the maximum Nusselt number ratio (Nu nanofluid/ Nu base fluid) and thermal performance factor
... Show MoreThe electronic payment systems are considered the most important infrastructure for the work of banks, particularly after a steady and remarkable development in information and communication technology, Which created the reality of the work of the infrastructure for these systems and these systems also become one of the most important components of infrastructure for the work of banks, cause it is one of the most important channels through which the transfer of cash, financial instruments between financial institutions in general and banking in particular.
In order to achieve the objectives of the research, the most important to identify the concept of electronic payment systems, and its divisions, and th
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