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Biodegradability of Plastics  [PDF]
Yutaka Tokiwa,Buenaventurada P. Calabia,Charles U. Ugwu,Seiichi Aiba
International Journal of Molecular Sciences , 2009, DOI: 10.3390/ijms10093722
Abstract: Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.
Historical Developments of BHR Humanoid Robots  [PDF]
Qiang Huang, Zhangguo Yu, Xuechao Chen, Weimin Zhang, Tianqi Yang, Wenxi Liao, Macro Ceccarelli
Advances in Historical Studies (AHS) , 2019, DOI: 10.4236/ahs.2019.81005
Abstract: Humanoid robots can achieve increasingly complex functions and adapt to more complex environments. To boost the development of humanoid robot technology, a team at Beijing Institute of Technology initiated the research on humanoid robots from 2000. Their research primarily focuses on stable walking, whole-body complex motion, human-robot interaction, and multimodal motion of humanoid robots. Thus far, the team has developed 6 generations of humanoid robots. The latest humanoid robot, BHR-6P, can achieve multi-mode motions (for example, walk, jump, fall protection, crawl and roll), which will significantly improve the ability of robot to adapt to the environment. This paper presented the historical evolution of BHR humanoid robots and outlined their functions and features.
Resource Prediction for Humanoid Robots  [PDF]
Manfred Kr?hnert,Nikolaus Vahrenkamp,Johny Paul,Walter Stechele,Tamim Asfour
Computer Science , 2014,
Abstract: Humanoid robots are designed to operate in human centered environments where they execute a multitude of challenging tasks, each differing in complexity, resource requirements, and execution time. In such highly dynamic surroundings it is desirable to anticipate upcoming situations in order to predict future resource requirements such as CPU or memory usage. Resource prediction information is essential for detecting upcoming resource bottlenecks or conflicts and can be used enhance resource negotiation processes or to perform speculative resource allocation. In this paper we present a prediction model based on Markov chains for predicting the behavior of the humanoid robot ARMAR-III in human robot interaction scenarios. Robot state information required by the prediction algorithm is gathered through self-monitoring and combined with environmental context information. Adding resource profiles allows generating probability distributions of possible future resource demands. Online learning of model parameters is made possible through disclosure mechanisms provided by the robot framework ArmarX.
Dynamics and Control of Humanoid Robots: A Geometrical Approach  [PDF]
Vladimir G. Ivancevic,Tijana T. Ivancevic
Physics , 2011,
Abstract: his paper reviews modern geometrical dynamics and control of humanoid robots. This general Lagrangian and Hamiltonian formalism starts with a proper definition of humanoid's configuration manifold, which is a set of all robot's active joint angles. Based on the `covariant force law', the general humanoid's dynamics and control are developed. Autonomous Lagrangian dynamics is formulated on the associated `humanoid velocity phase space', while autonomous Hamiltonian dynamics is formulated on the associated `humanoid momentum phase space'. Neural-like hierarchical humanoid control naturally follows this geometrical prescription. This purely rotational and autonomous dynamics and control is then generalized into the framework of modern non-autonomous biomechanics, defining the Hamiltonian fitness function. The paper concludes with several simulation examples. Keywords: Humanoid robots, Lagrangian and Hamiltonian formalisms, neural-like humanoid control, time-dependent biodynamics
Fiber Reinforced Self Compacting Concrete Using Domestic Waste Plastics as Fibres
R. Kandasamy,R. Murugesan
Journal of Engineering and Applied Sciences , 2012, DOI: 10.3923/jeasci.2012.405.410
Abstract: Fiber Reinforced Self Compacting Concrete (FRSCC) is a composite material consisting of cement based matrix with an ordered or random distribution of fiber which can be steel, nylon and polythene, etc., which offers several economical and technical benefits. In this study, domestic waste plastics (Polythene fibres) were used and the properties of concrete (viz., compressive strength, flexural strength, split tensile strength) are studied. The tests have been carried out as per EFNARC for fresh concrete and Indian Standard Code for hardened concrete.
Degradation of Plastics in Seawater in Laboratory  [PDF]
Juan C. Alvarez-Zeferino, Margarita Beltrán-Villavicencio, Alethia Vázquez-Morillas
Open Journal of Polymer Chemistry (OJPChem) , 2015, DOI: 10.4236/ojpchem.2015.54007
Abstract: Degradable plastics are used as a way to decrease the environmental impact of these materials when they become waste. However, they can reach natural ecosystems due to littering and bad management. This research assesses the performance of oxodegradable and compostable plastics on marine environments through a respirometric lab test. Probes of the plastics, with and without previous simulated weathering, were put in contact for 48 days with a marine inoculum, in a system that guarantees continuous aeration and capture of the produced CO2. After the test, the samples were also assessed in terms of their loss of mechanical properties. The compostable plastic exhibited the higher degree of mineralization (10%), while there was no difference between the polyolefins (2.06% - 2.78%), with or without presence of pro-oxidants or previous abiotic degradation. On the other hand, exposition to UV light promoted a higher loss of elongation at break in the oxodegradables plastic (>68%). The results show that the studied plastics achieve very low biodegradation rates while presenting a higher rate of loss of physical integrity. This combination of phenomena could lead to their fragmentation before significant biodegradation can occur. The risk of microplastics formation must be prevented by avoiding the presence of the materials in marine environments, even if they have shown suitability for some waste management scenarios.
Humanoid Dynamic Controller
Rui Monteiro,Luis Paulo Reis,Antonio Correia Pereira
TELKOMNIKA : Indonesian Journal of Electrical Engineering , 2012, DOI: 10.11591/telkomnika.v10i8.1440
Abstract: In the last years several investigators have focused on the development and control of humanoid robots able to acquire human behaviors, and features in order to be able to interact with humans and work together with them. The fall of a robot can lead to damages, which entail costs for repair, or even human health risks so ensuring stability is a main concern in terms of cost and safety. This document presents the implementation of a dynamic controller for robots, able to position the robot's center of mass in a certain location operating as a stability module. It is also described a precise behaviour of preparing an omnidirectional kick by placing the support foot of the robot in a precise position and orientation calculated in accordance with the robot's position, the ball and the target, and by transferring the robot's center of mass to the desired position.
MODELING AND SIMULATION OF ROBOTIC HUMANOID ARM
RANJEET RANJAN,DR. ARBIND KUMAR,DR. PRAVEEN DHYANI
International Journal of Engineering Science and Technology , 2012,
Abstract: In this paper block model and machine model of Robotic humanoid arm has been generated Using MATLAB Simulink. Equations of Kinematics are derived by using D-H notation. By this equation and inverse kinematicsparameters for the motion trajectory have been determined. Kinematic parameters are divided into two groups namely, link parameters and joint parameters. Geometric model and motion of robotic humanoid arm with two link model with 3 Degree of freedom and arm with palm and fingers with 18 degree of freedom has been realized. Virtual simulation of the arm is also first step in actually controlling the mechanical structure.
Interactive Learning for Humanoid Robot  [PDF]
Elsayed Mostafa Saad,Medhat Hussin Awadalla,Hosam Eldin Ibrahim Ali,Rasha Fathy Aly Mostafa
International Journal of Computer Science Issues , 2012,
Abstract: Acquiring new knowledge through interactive learn-ing mechanisms is a key ability for humanoid robots in a natural environment. Such learning mechanisms need to be performed autonomously and through interaction with the environment or with other agents/humans. This paper proposes a vision system, where robot can learn how to identify the geometric shapes and colors of the objects. Furthermore, the paper proposes a natural language understanding system, where the robot can learn to effectively communicate with human through a dialogue developed in Arabic language. The developed di-alogue and a dynamic object model are used for learning semantic categories, object descriptions, and new words acquisition for object learning. Moreover, integration between the proposed vision and natural language understanding systems has been presented. Intensive experiments have been conducted indoor to address the validity of the proposed system. The achieved results show that the overall system performance is high compared with the related literature to the theme of this paper.
POLYHYDROXYALKONATES: GREEN PLASTICS OF THE FUTURE  [cached]
Anushri Saxena,Archana Tiwari
International Journal of Biomedical and Advance Research , 2011, DOI: 10.7439/ijbar.v2i9.48
Abstract: Plastic waste disposal is a major ecotechnological problem. One of the major approaches to solve this problem is the use of biodegradable biopolymer. Polyhydroxyalkanoates (PHAs) are biodegradable polymers of hydroxyalkonates, which are accumulated as energy storage material in various microorganisms to overcome environmental stress. Polyhydroxyalkanoates have gained major importance due to their structural diversity and close analogy to plastics and have attracted attention as biodegradable alternatives to conventional thermoplastics and as biomaterials. According to the variations in toughness and flexibility they can be used in various ways similar to many non biodegradable petro plastic which are currently in use. The need is to produce PHAs, which have better elastomeric properties suitable for its various applications. This review gives an overview on biodegradability and commercial reliability of PHA.
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