• Energy Research
• Open Access close
• Closed Access close
• Restricted close
• engineering and technology close
• English close

In this paper, the mathematical analysis of the robot effective mass is presented. The calculation of this effective mass and its ellipsoid are included. The relationship between the robot effective mass and the external force (collision) affecting the robot end-effector is investigated. The effective mass is analyzed using different robot configurations and different end-effector positions. This analysis is conducted using 2-DOF and 3-DOF planar robots and executed using MATLAB. The results from this analysis prove that the robot effective mass depends on the its configurations and end-effector position. Effective mass can thus be considered as one of the criteria in optimizing robot kinematics and configuration.

Pada umumnya sistem kendali robot wall follower menggunakan kontroler PID (Proportional Integral Derivative). Hasil output dari penggunaan sistem kontrol jenis ini terkadang dapat membuat pergerakan robot menjadi tidak stabil dan kaku jika diberikan nilai acuan (konstanta) yang tidak seseuai. Itu disebabkan karena apabila diberi nilai konstanta uang tidak sesuai, maka respon dari robot jika ada gangguan (Disturbance) dapat menyebabkan nilai overshoot yang tinggi. Agar dapat mengatasi permasalahan ini, di perlukan suatu persamaan Osilasi untuk mengatur seluruh nilai konstantan PID, Persamaan Osilasi disini berfungsi untuk membantu menentukan nilai konstanta PID untuk memperkecil overshoot. Dari metode ini didapatkan hasil yaitu pergerakan robot semakin stabil dengan overshoot yang kecil.Kata kunci—Wall follower, Proportional Integral Derivative, Arduino

This paper conveniently skips any controversy associated with the science of climate change. On the assumption that greenhouse gas emissions are causing climate change that is detrimental to humanity, the paper focuses on some economic dimensions of the issue which seem to be poorly understood by Australian media commentators, policy analysts, interest groups and the political parties. Using a neoclassical welfare economics framework the paper explores the costs and benefits of greenhouse gas abatement with reference to the findings of the Stern Report, the setting of greenhouse gas targets by Australian political parties, the danger of the government “picking winners” and the emerging carbon theory of value. The paper concludes with a brief review of the relative merits of a carbon tax and a cap and trade approach. Key Words: This paper conveniently skips any controversy associated with the science of climate change. On the assumption that greenhouse gas emissions are causing climate change that is detrimental to humanity, the paper focuses on some economic dimensions of the issue which seem to be poorly understood by Australian media commentators, policy analysts, interest groups and the political parties. Using a neoclassical welfare economics framework the paper explores the costs and benefits of greenhouse gas abatement with reference to the findings of the Stern Report, the setting of greenhouse gas targets by Australian political parties, the danger of the government “picking winners” and the emerging carbon theory of value. The paper concludes with a brief review of the relative merits of a carbon tax and a cap and trade approach.

OPTICA APPLICATA; 04/2013; ISSN 1429-7507

{"references": ["C. W. Taylor, Power System Voltage Stability (McGraw-Hill, Inc.,\nNewYork, America, 1994).", "P. W. Sauer, M. A. Pai, Power system steady-state stability and the loadflow\nJacobian, IEEE Transactions on Power Systems, vol. 5 n. 4,\nNovember 1990, pp. 1374 - 1383.", "N. Yorino, H. Sasaki, Y. Masuda, Y. Tamura, M. Kitagawa and A.\nOshimo, An investigation of voltage instability problems, IEEE\nTransactions on Power Systems, vol. 7 n. 2, May 1992, pp. 600 - 611.", "P. -A. L\u00f6f, G. Andersson, D. J. Hill, Voltage stability indices for\nstressed power systems, IEEE Transactions on Power Systems, vol. 8 n.\n1, February 1993, pp. 326 - 335.", "G. K. Morison, B. Gao, P. Kundur, Voltage stability analysis using static\nand dynamic approaches, IEEE Transactions on Power Systems, vol. 8\nn. 3, August 1993, pp. 1159 - 1171.", "B. Lee, V. Ajjparapu, Invariant subspace parametric sensitivity (ISPS) of\nstructure-preserving power system models, IEEE Transactions on Power\nSystems, vol. 11 n. 2, May 1996, pp. 845 - 850.", "M. Chakravorty, and D. Das, Voltage stability analysis of radial\ndistribution networks, International Journal of Electrical Power &\nEnergy Systems, vol. 23 n. 2, February 2001, pp. 129 - 135.", "G. Verbic, F. Gubina, A new concept of protection against voltage\ncollapse based on local phasors, IEEE Transactions on Power Delivery,\nvol. 19 n. 2, April 2004, pp. 576 - 581.", "F. Gubina, B. Strmcnik, Voltage collapse proximity index determination\nusing voltage phasors approach, IEEE Transactions on Power Systems,\nvol. 10 n. 2, May 1995, pp. 788 - 794.\n[10] S. Satyanarayana, T. Ramana, S. Sivanagaraju, G. K. Rao and P.V.\nPrasad, A Novel Approach to Evaluate the Maximum Loadability of\nDistribution systems with Voltage dependent load models, ELEKTRIKA,\nvol. 12 n. 1, 2010, pp. 19 - 24.\n[11] M. Moghavemmi, F. M. Omar, Technique for contingency monitoring\nand voltage collapse prediction, IEE Proceedings Generation\nTransmission Distribution, vol. 145 n. 6, November 1998, pp. 634 - 640.\n[12] V. Balamourougan, T. S. Sidhu, M. S. Sachdev, Technique for online\nprediction of voltage collapse, IEE Proceedings Generation\nTransmission Distribution, vol. 151 n. 4, July 2004, pp. 453 - 460.\n[13] K. Vu, M. M. Begovic, D. Novosel, and M. M. Saha, Use of local\nmeasurements to estimate voltage-stability margin, IEEE Transactions\non Power Systems, vol. 14 n. 3, August 1999, pp. 1029 - 1035.\n[14] M. Begovic, B. Milosevic, D. Novosel, A novel method for voltage\ninstability protection, 35th Hawaii International Conference on System\nSciences~HICSS-35~,January 7-10, 2002, Big Island, HI, USA.\n[15] I. Smon, G. Verbic, F. Gubina, Local voltage-stability index using\nTellegen-s theorem, IEEE Transactions on Power Systems, vol. 21 n. 3,\nAugust 2006, pp. 1267 - 1275.\n[16] K. Nagaraju, T. Ramana, S. Sivanagaraju and P.V. Prasad, A Novel\nLoad Flow Method for Radial Distribution System, International\nJournal of Power and Energy Systems, vol. 31 n. 1, 2011, pp. 73 - 81.\n[17] Power system engineering committee, Bibliography on load models for\npower flow and dynamic performance simulation, IEEE Transactions on\nPower Systems, vol. 10 n. 1, February 1995, pp.523 - 538."]} This paper presents a simple method for estimation of additional load as a factor of the existing load that may be drawn before reaching the point of line maximum loadability of radial distribution system (RDS) with different realistic load models at different substation voltages. The proposed method involves a simple line loadability index (LLI) that gives a measure of the proximity of the present state of a line in the distribution system. The LLI can use to assess voltage instability and the line loading margin. The proposed method also compares with the existing method of maximum loadability index [10]. The simulation results show that the LLI can identify not only the weakest line/branch causing system instability but also the system voltage collapse point when it is near one. This feature enables us to set an index threshold to monitor and predict system stability on-line so that a proper action can be taken to prevent the system from collapse. To demonstrate the validity of the proposed algorithm, computer simulations are carried out on two bus and 69 bus RDS.

This work has been developed under the AGROinLOG Project, “Demonstration of innovative integrated biomass logistics centres for the Agro-industry sector in Europe”. An Integrated Biomass Logistics Center (IBLC), is based on the introduction of new production chains into existing agro-industries by using new biomass feedstock. The AGROinLOG Project has dedicated great attention to investigate the potential of cereal chaff as a valuable resource.Chaff is the fine fraction of the thrashing residues, not usually collected. Chaff is made up of glumes, seed husks, rachis and the tinner part of the cereal stems, whole and cracked kernels, as well as weed seeds.Currently there are several mechanical solutions available on the market for chaff recovery, and others are still at prototype stage, but theyare not so common and very often unknown to the farmers.So far, the literature reportsfew cases of chaff collection with the specific purpose of weed seeds removal, but it still lacks specificexperiments on these machinesintentionally used for biomass collection.For this reason, during the Project AGROinLOG a series of large field tests were performed using an independent scientific approach with different kind of chaff harvesting technologiesin France, Sweden and Italy from 2017 to 2019.The present study collects the results of these activities with the aim to fill that gap and provide deeper understanding in the possibility to enhance the current cereal harvesting method, in order to improve the quantity of biomass collected by including the chaff. Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 62-68

A new Multi-Stage Fuzzy (MSF) controller based on Multi-objective Harmony Search Algorithm (MOHSA) is proposed in this paper to solve the Load Frequency Control (LFC) problem of power systems in deregulated environment. LFC problem are caused by load perturbations, which continuously disturb the normal operation of power system. The objectives of LFC are to mini small size the transient deviations in these variables (area frequency and tie-line power interchange) and to ensure their steady state errors to be zero. In the proposed controller, the signal is tuned online using the knowledge base and fuzzy inference. Also, to reduce the design effort and optimize the fuzzy control system, membership functions are designed automatically by the proposed MOHSA method. Obtained results from the proposed controller are compared with the results of several other LFC controllers. These comparisons demonstrate the superiority and robustness of the proposed strategy.