THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

The science and technology of ultracapacitors are reviewed for a number of electrode materials, including carbon, mixed metal oxides, and conducting polymers. More work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and an organic electrolytes. The energy density of these devices is 3¯5 Wh/kg with a power density of 300¯500 W/kg for high efficiency (90¯95%) charge/discharges. Projections of future developments using carbon indicate that energy densities of 10 Wh/kg or higher are likely with power densities of 1¯2 kW/kg. A key problem in the fabrication of these advanced devices is the bonding of the thin electrodes to a current collector such the contact resistance is less than 0.1 cm2. Special attention is given in the paper to comparing the power density characteristics of ultracapacitors and batteries. The comparisons should be made at the same charge/discharge efficiency.

Ultracapacitors: Why, How, and Where is the Technology

In this paper, we wish to present an overview of the research carried out in our laboratories with low-cost transition metal oxides (manganese dioxide, iron oxide and vanadium oxide) as active electrode materials for aqueous electrochemical supercapacitors. More specifically, the paper focuses on the approaches that have been used to increase the capacitance of the metal oxides and the cell voltage of the supercapacitor. It is shown that the cell voltage of an electrochemical supercapacitor can be increased significantly with the use of hybrid systems. The most relevant associations are Fe3O4 or activated carbon as the negative electrode and MnO2 as the positive. The cell voltage of the Fe3O4/MnO2 device is 1.8 V and this value was increased to 2.2 V by using activated carbon instead of Fe3O4. These two systems have shown superior behavior compared to a symmetric MnO2/MnO2 device which only works within a 1 V potential window in aqueous K2SO4. Furthermore, the activated carbon/MnO2 hybrid device exhibits a real power density of 605 W/kg (maximum power density =19.0 kW/kg) with an energy density of 17.3 Wh/kg. These values compete well with those of standard electrochemical double layer capacitors working in organic electrolytes.

http://ma.ecsdl.org/content/MA2005-01/35/1348.full.pdf

Nanostructured Transition Metal Oxides for Aqueous Hybrid Electrochemical Supercapacitors

Electric vehicles (EV), including Battery Electric Vehicle (BEV), Hybrid Electric Vehicle (HEV), Plug-in Hybrid Electric Vehicle (PHEV), Fuel Cell Electric Vehicle (FCEV), are becoming more commonplace in the transportation sector in recent times. As the present trend suggests, this mode of transport is likely to replace internal combustion engine (ICE) vehicles in the near future. Each of the main EV components has a number of technologies that are currently in use or can become prominent in the future. EVs can cause significant impacts on the environment, power system, and other related sectors. The present power system could face huge instabilities with enough EV penetration, but with proper management and coordination, EVs can be turned into a major contributor to the successful implementation of the smart grid concept. There are possibilities of immense environmental benefits as well, as the EVs can extensively reduce the greenhouse gas emissions produced by the transportation sector. However, there are some major obstacles for EVs to overcome before totally replacing ICE vehicles. This paper is focused on reviewing all the useful data available on EV configurations, battery energy sources, electrical machines, charging techniques, optimization techniques, impacts, trends, and possible directions of future developments. Its objective is to provide an overall picture of the current EV technology and ways of future development to assist in future researches in this sector.

https://www.preprints.org/manuscript/201705.0090/v1/download

A Comprehensive Study of Key Electric Vehicle (EV) Components, Technologies, Challenges, Impacts, and Future Direction of Development

One-step preparation of layered molybdenum disulfide/multi-walled carbon nanotube composites for enhanced performance supercapacitor

Development, modeling and characterization of aqueous metal oxide based supercapacitor

Scarcity of electric power, in developing countries like India, demands more generation of electric power. The conventional means of generating power are much time consuming and hence it is necessary to utilize renewable energy sources like wind, solar etc. Wind is intermittent in nature. It is not possible to predict exact wind speed because of the continuously changing climatic conditions. So flicker i.e. change in voltage is produced because of change in wind speed. It creates nuisance to the consumers. Consumers observe flicker in light of the incandescent lamp. So it is very difficult to read in that light source. So it is necessary to quantify and reduce the flicker emission severity produced by wind turbine. Now a days while computing flicker emission severity, only wind speed and grid impedance phase angle are considered. In this paper new parameter vertical wind shear is also considered while computing the flicker emission severity. Experimental results are of a turbine installed at Village Nimgaon Mhalungi, Tal. Shirur, District Pune, India.

Effect of vertical wind shear on flicker in wind farm

This paper bequeaths particulars of impact of turbulence on the flicker produced in the wind turbine which is sited on that surface. This is achieved in a laboratory wind tunnel with small models of hills with different slopes and wind turbine. Different shapes of models of hills placed in a laboratory wind tunnel. Wind turbines are tested for those conditions. The paper provides an empirical model to find flicker in terms of hill topography. The exquisiteness of the model is that, it is expedient to sundry types hills on which the turbine is sited. Validation of model is carried out with comparative graphs revealed with readings recorded on a turbine in tunnel.

Assessment of flicker owing to turbulence in a wind turbine placed on a hill using wind tunnel

In this paper, specifics of impact of sea shore environment on vertical wind shear and congruently on flicker in wind turbine which is sited on that surface is reverberated. This is achieved in a laboratory wind tunnel with artificial surfaces created in a wind tunnel. The various surfaces imitated in the wind tunnel are sea sand of various sizes. Wind turbine is tested for these diverse types of surface roughness. Empirical model of flicker reflecting vertical wind shear at sea shore is established. Conjectures made while proposing the empirical model are reverberated. Boundary verges of the projected empirical model are echoed. Comparative graphs of flicker initiated due to vertical wind shear because of various sizes of sands on the seashore are portrayed. Values of flicker with projected empirical model and flicker from wind tunnel test are closer.

Empirical model of flicker due to vertical wind shear instigated by civilization in a seashore wind turbine using wind tunnel

Paper presents a newfangled empirical model to figure, flicker, instigated in the horizontal axis, upwind turbine, due to wind turbulence, in continuous operation. Postulations, boundary curbs and limitations of the model are also depicted. In the proposed model, wind turbulence, number of blades, blade length and tower height are echoed. The exquisiteness of the model is that, it is expedient to range of heights of structures on which the turbine is sited. Validation of model is carried out with comparative graphs revealed after vigorous experimentation on a turbine in a tunnel with various heights of models of buildings.

http://ieeexplore.ieee.org/iel7/7045158/7054731/07054810.pdf

P. B. Karandikar

Papers

Development, modeling and characterization of aqueous metal oxide based supercapacitor

Effect of vertical wind shear on flicker in wind farm

Assessment of flicker owing to turbulence in a wind turbine placed on a hill using wind tunnel

Empirical model of flicker due to vertical wind shear instigated by civilization in a seashore wind turbine using wind tunnel

Computation of flicker as a result of turbulence in a wind turbine sited on a green building using wind tunnel