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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.

In this article, a large area bifacial solar cell on n-type silicon substrates using novel process and only industrial facilities is introduced. The boron emitter is formed by BCl3 precursor and the phosphorus BSF is made by ionimplantation followed by in-situ front and rear side passivation with silicon oxide. Meanwhile, the wafer source and cell series resistance affiliated to process control variability are analyzed. The resulting cell efficiency achieved 19.7% on 156 PSQ n-type Cz wafers. Moreover, such process was adopted on 156 inch n-type mono-like wafers and achieved cell efficiency up to 18.9%. 28th European Photovoltaic Solar Energy Conference and Exhibition; 1053-1056

Lignite-fired power plants in Northern Greece produce about 50% of the electricity and account for nearly 60% of the allocated CO2 emissions. The implementation of biomass co-firing is considered a cost effective and efficient method for minimizing GHG emissions. However, despite a favorable legislative framework, co-firing in Greece has not progressed since low lignite costs and distance of power plants from harbor facilities limit access to internationally traded solid biomass. The improvement and optimization of local biomass supply chains is thus a strategic priority in the national context. The purpose of the present work is to present preliminary investigations of a wheat straw supply chain for a Greek lignite-fired power plant to be converted into biomass co-firing operation. On¬field demonstration data are analyzed in order to estimate costs for supply chains involving either pelletized straw or straw bales. Information of energy consumption is also presented for different cases and GHG emissions calculated according to the methodology of (COM 2010)11. Results indicate that the cost of straw delivered at the power plant varies depending on whether pelletization is included as a supply chain step. Overall, over short distances, transfer of baled biomass is more economic and results in lower GHG emissions, however the increase in the cost of the supply chain suggest that a pelletization step should be considered for longer distances. The transport cost of the supply chain also depends on whether the vehicles are assumed to return empty at their starting point or loaded. Also, compared to imported or domestic wood pellets, straw pellets have lower prices and could be more attractive to plant operators. Long-term fuel contracts are essential in order to ensure the financial viability of co-firing, especially if a reduction in the feed-in tariff is expected. Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 136-142