E-ISSN 0976-7916
  Journal of Engineering  Research and Studies
                                                            -An Open Access Peer Reviewed e-Journal

 

 
 

SIGNIFICANCE OF EMPIRICAL AND PHYSICAL PROPAGATION MODELS TO CALCULATE THE EXCESS PATH LOSS

 

Authors: Kiran Ahuja Manoj Kumar

 

JERS/ Volume II/ Issue II/April-June, 2011/1-6

ABSTRACT
In this paper, we have reported the significance of empirical & physical propagation models to calculate the excess path loss by predicting the field strength at a precise point in space by considering the specific propagation environment. Out of the various empirical & physical propagation models, empirical models viz. Free Space, FCC, ITUR370, Okumura (HATA) and physical models viz. TIREM, Anderson 2D v1.00 have been considered. Each model calculates the value of excess path loss (the path loss occurring in addition to the free space path loss). Further it has been reported that the selection of the appropriate model and signal level statistics for system design will depend on the type of system and the area where it will be used.

TECHNIQUES FOR REDUCTION OF MULTIPLE ACCESS INTERFERENCE IN FIBER-OPTIC CDMA SYSTEMS

 

Authors: Jaswinder Singh

 

JERS/ Volume II/ Issue II/April-June, 2011/7-10

ABSTRACT
Fiber-optic CDMA is an emerging technology with far more advantages than the conventional TDMA and FDMA techniques. The only limitation of FO-CDMA is the multiple access interference among the users simultaneously accessing the network. This paper reviews the techniques proposed in the literature for the reduction of multiple access interference (MAI) between the users simultaneously accessing the network in fiber-optic CDMA systems. Two important techniques: Successive Interference Cancellation and Differential Detection have been discussed in detail.

CASES OF INSTABILITY IN TIME DELAYED AMMENSALISM

 

Authors: K.V.L.N.Acharyulu

 

JERS/ Volume II/ Issue II/April-June, 2011/11-16

ABSTRACT
In this paper, the author concentrates on the cases of instability in a mathematical model of Ammensalism between two species in which a delayed Ammensal is comprised. More over both the species are assumed to have limited resources. Three equilibrium points of the model are identified as unstable. Further exact solutions of perturbed equations are derived and consequences are explained.

PRINTING PAPERS: SIZING AND ITS ROLE

 

Authors: Manisha S. Deshpande

 

JERS/ Volume II/ Issue II/April-June, 2011/17-21

ABSTRACT
This document gives information about water resistant property of paper i.e. sizing. It gives details of sizing materials and requirement of properties for different printing methods.

LOW PASS FILTER FOR L-BAND APPLICATION USING STEPPED-IMPEDANCE MICROSTRIP LINES

 

Authors: Navita Singh, Dr.Avinash Kumar and Pravesh Singh

JERS/ Volume II/ Issue II/April-June, 2011/22-24

ABSTRACT
There is an increasing demand for newer microwave and millimeter-wave systems to meet the emerging telecommunication challenges with respect to size, performance and cost. This paper presents a low cost and low insertion loss L-band lowpass filter (LPF) based on high-resistivity silicon substrate. Microstrip technology is used for simplicity and ease of fabrication. The design and simulation are performed using 3D full wave electromagnetic simulator IE3D. The simulated filter achieved an insertion loss of less than 1.0dB in the passband. The filter has a center fiequency of 1.5GHz with covering the frequency range from 0.5 GHz to 1.55 GHz.

A NEW APPROACH TO CALCULATE ONLINE DELTA TIME MOMENTS FROM INPUT-OUTPUT RESPONSE OF PLANT

 

Authors: Souvik Ganguli

 

JERS/ Volume II/ Issue II/April-June, 2011/25-27

ABSTRACT
This paper addresses a novel method to compute the time moments in delta domain. Time moment method is a tool so far used for model order reduction. Here it is applied to compute online time moments from the input-output response of the plant. The delta operator representation is considered to derive the benefit of unification of design method to its continuous-time counterpart at higher sampling frequency. The delta time moments obtained will further be applied for controller design in delta domain.

STABILITY CASE IN A MATHEMATICAL MODEL OF TIME DELAYED AMMENSAL AND AN ENEMY ECOLOGICAL SPECIES WITH LIMITED RESOURCES 

 

Authors: K.V.L.N.Acharyulu

 

JERS/ Volume II/ Issue II/April-June, 2011/28-33

ABSTRACT
The objective of the paper is to examine the stability case in a mathematical model of Ammensalism between two species in which a delayed Ammensal is comprised. Here both the enemy and the Ammensal species are having limited resources. Four equilibrium points of the model are discovered. The stability criteria of co-existent state only are derived. Solutions for the linearized perturbed equations are detected and results are explained.

EVALUATION OF CSRZ FORMAT IN THE PRESENCE OF FIBER IMPAIRMENTS IN FIBER-OPTIC CDMA

Authors: Jaswinder Singh

 

JERS/ Volume II/ Issue II/April-June, 2011/34-35

 

ABSTRACT
The performance analysis of a fiber-optic CDMA system is carried out to study the impact of fiber nonlinearities using CSRZ format. The coders are designed using the GRZI-BCDD codes. Since these are 3-D wavelength-time-space codes, these are converted into 2-D wavelength-time codes so that their requirement of space couplers and fiber ribbons is eliminated. The performance analysis is carried out by simulating a four-user system using OptSIM, simulation tool from RSoft. CSRZ has been used for its resilience towards the non-linear effects.

STUDY ON THE COMPRESSION AND IMPACT STRENGTH OF GFRC WITH COMBINATION OF ADMIXTURES

 

Authors: P. Sangeetha

 

JERS/ Volume II/ Issue II/April-June, 2011/36-40

ABSTRACT
High performance fiber reinforced concrete increases the Compressive, Impact and Flexural Strength. The aim of this experimental work is to study the effect of addition of admixtures in glass fiber reinforced concrete. Nearly Forty Standard Specimens are tested to failure under a constant axial load for to study the compressive strength and forty standard impact specimens are tested by drop weight method to study the Impact strength of the material. The Parameters that are varied in the experimental work includes Percentage of fiber. [0, 0.1, 0.2 and 0.3% weight of concrete]. Different combinations of admixtures Superplasticiser + Air entraining agent + Accelerator [S+AEA+A], Superplasticiser + Air entraining agent + Retarder [S+AEA+R] Superplasticiser + Air entraining agent + Water proofing compound [S+AEA+W]. Glass Fiber Reinforced Concrete with Different combination of admixtures increases the compressive strength (10%) and Impact Strength (100%).

HUMAN RESOURCE MANAGEMENT IN PRINTING INDUSTRY WITH REFERENCE TO RECRUITMENT AND SELECTION

 

Authors: Manisha Deshpande

JERS/ Volume II/ Issue II/April-June, 2011/41-42

 

ESTIMATION OF ANNUAL ENERGY GENERATION FROM A SMALL GRID CONNECTED SOLAR PHOTOVOLTAIC POWER PLANT IN PATIALA

 

Authors: Souvik Ganguli*, Sunanda Sinha

 

JERS/ Volume II/ Issue II/April-June, 2011/43-44

ABSTRACT
This paper reports a proposed grid connected solar photovoltaic power plant at Thapar University, Patiala that would utilize a vacant area of about 100 m2 available on the terrace of the academic wing of the building. The SPV power plant with proposed capacity of 9 kWp would be connected to grid. No battery storage has been considered in this work. It would meet partial load of the building during working days and feed the surplus power available to the grid during weekends and other holidays. The grid connected SPV project would be a demonstration plant to harness renewable energy and the data on generation would be utilized for analysis of the various aspects of operation as also that of availability of power. The 9 kWp SPV power plant is estimated to afford annual energy feed of 11.76 MW-hr considering efficiency of the solar module as 14.3 %, inverter or power conditioning unit (PCU) as 94% and losses as 3% in the DC and AC system. The plant would operate at an annual capacity utilization factor of 19%. The energy available from the plant varies from a minimum of 0.53 MW-hr during the month of December to a maximum of 1.35 MW-hr during the month of April.

THERMAL TRANSPORT IN A COUPLED SINUSOIDAL FRACTURE MATRIX SYSTEM IN THE PRESENCE OF FRACTURE SKIN

 

Authors:N.Natarajan* and G. Suresh Kumar

 

JERS/ Volume II/ Issue II/April-June, 2011/45-49

ABSTRACT
Modeling of fluid flow through fractured rock is an important aspect of many disciplines, especially in geothermal energy production. A few studies have been conducted in the coupled fracture matrix system in the presence of fracture skin using parallel plate model. An attempt has been made to simulate thermal transport in sinusoidal fracture-skin-matrix coupled system numerically. Results suggest that the spatial variation of the fracture aperture along the fracture affects the heat transfer at the fracture-skin interface and thus enhances the heat transfer between the fracture and the rock matrix. The variation in the fracture skin thermal conductivity has marginal effect on the heat transfer mechanism in the coupled sinusoidal fracture skin matrix system due to the curvature effect of the fracture and small fracture aperture.

AN EFFICIENT APPROACH FOR CAPACITOR SIZING AND LOCATION ON A RADIAL DISTRIBUTION SYSTEM USING ARTIFICIAL INTELLIGENCE TECHNIQUE

 

Authors: Shikha Gupta, Gursewak Singh Brar

 

JERS/ Volume II/ Issue II/April-June, 2011/50-54

ABSTRACT
This paper undertakes the problem of optimal shunt capacitor placement for loss reduction in a radial distribution feeder. The problem is to determine the optimum size and location of the capacitors to be placed on a RDS. The objective function is to have maximization of saving due to reduction of energy losses thereby taking into consideration cost of capacitor. The solution methodology used divides the problem into two parts. In first part, load flow solution for the radial feeder is obtained and followed by a loss sensitivity analysis to select the candidate capacitor installation locations. In second part, Genetic algorithm is used as an optimization tool, which obtains the optimal value of capacitors to be installed. The solution algorithms have been implemented into and tested on a 33-bus radial distribution system. Test results demonstrate the effectiveness of the developed algorithm. Computational results are calculated in MATLAB 7.

QUANTITATIVE AND QUALITATIVE ASSESSMENT OF MUNICIPAL SOLID WASTE FOR NAGPUR CITY

 

Authors: Pankaj R.Modak*, Prakash B. Nangare

 

JERS/ Volume II/ Issue II/April-June, 2011/55-61

 

ABSTRACT
Municipal Solid Waste(MSW) management practices in Nagpur, a Orange city in Maharashtra,India, were examined in detail and an integrated solid waste management plan proposed based on the study results. Rapid economical growth, increasing population and change in living standards of city causes a high generation rate of MSW. This paper analyses and compares the findings of the study of the characterization and the generation of solid waste from ten different zones of city. At present, the total solid waste generated in Nagpur Municipality is 504 tons/day, but the waste collected by the Municipality is about 300 tons/day, which implies that almost 204 tons/day of the solid waste remains uncollected. Fifty samples were characterized physically and their proximate analyses were done in the laboratory. The average values of various parameters were observed as organic content (25%), C/N ratio (30±5), Calorific value (780-1010 K Cal/kg), Moisture content (26%), NPK value(0.49, 0.48 & 0.43 resp.), etc. Augmentation in labour and vehicle inventory has been proposed along with better treatment and disposal facilities. MSW of Nagpur has high C/N ratio, high moisture content and high organic content, making composting and sanitary landfilling the best treatment strategy.

INTEGRATED MANAGEMENT SYSTEM (IMS): MODEL & MEASURES OF NANOMATERIALS

 

Authors: Indrajit N. Yadav

 

JERS/ Volume II/ Issue II/April-June, 2011/62-67

ABSTRACT
In the traditional view, strong competition and high innovation go hand in hand, as long as product markets are not impeded by state environmental regulations. While novel chemicals such as nanomaterials that make life more convenient are being rapidly developed, regulations against such chemicals have been strengthened from the perspective of public health concerns and environmental protection, spurred by an enhancement of the available knowledge. An evaluation was made of the recently developed chemical risk assessment methodologies for new and existing previous term chemicals. The evaluation also included the methodologies and procedures for risk guidance document for the development of strategies for risk reduction. Clear progress has been made in the development and harmonization of chemical risk assessment methodologies and the application of estimation methodologies. Nevertheless, improvements are necessary for the estimation of consumer and occupational exposure, the derivation, use and transparency of assessment factors based on the mode of toxic action, environmental exposure models and their validation and relation with monitoring data. The primary purpose of this paper is model integrated management system, therefore, first focuses on the collection and compilation of relevant findings on the potential effects of industrial nanoparticles that could impact human health and/or the environment.

THREE DIMENSIONAL VIRTUAL ENVIRONMENT FOR SECURED AND RELIABLE AUTHENTICATION

 

Authors: Gauri Rao, Dr. S.H. Patil

 

JERS/ Volume II/ Issue II/April-June, 2011/68-75

ABSTRACT
Present authentication systems have many weaknesses. Textual passwords are widely used. Users generally choose meaningful words from dictionaries, which make textual passwords easy to hack and vulnerable to dictionary or brute force attacks. Many available graphical passwords have a password space that is less than or equal to the textual password space .Smart cards or tokens can be stolen. Many biometric authentications have been proposed; however, users tend to resist using biometrics because of their intrusiveness and the effect on their privacy. We have designed a multifactor authentication scheme. To be authenticated, we present a 3-D virtual environment where the user navigates and interacts with various objects. The sequence of actions and interactions toward the objects inside the 3-D environment constructs the user’s 3-d password. This system can combine most existing authentication schemes into a 3-D virtual environment. The design of the 3-D virtual environment and the type of objects selected determine the key space.

ENHANCEMENT OF CONDENSATION HEAT TRANSFER OVER HORIZONTAL INTEGRAL-FIN TUBES- A REVIEW STUDY

 

Authors: Rathod Pravin P*, Ravi Kumar, Akhilesh Gupta

 

JERS/ Volume II/ Issue II/April-June, 2011/76-81

ABSTRACT
This paper reviews nearly seventy five years of progress that has been made in our understanding of film condensation on horizontal, integral fin tubes particular attention is given to low surface tension fluids (Refrigerants) which are prime concern now a day’s. Both experimental and theoretical developments pertaining to single tubes. Special attention is given to fluids which are using enhancement of fins according to increase the condensation heat transfer coefficient. The energy crisis and the requirement of efficient heat recovery systems have dilated the efforts to enhance the heat transfer during condensation of vapour in surface condensers.

FOUNTAIN SOLUTION IN LITHOGRAPHIC OFFSET PRINTING

 

Authors: Mr. Sameer S. Deshpande.

 

JERS/ Volume II/ Issue II/April-June, 2011/82-88

ABSTRACT
This document gives information about contents of fountain solution and their functions. It also describes the major performance attributes of the fountain solution.

APPLICATIONS OF COMPOSITES IN MARINE INDUSTRY

 

Authors: Dr. S. Selvaraju, S.Ilaiyavel

 

JERS/ Volume II/ Issue II/April-June, 2011/89-91

ABSTRACT
A Composite material is a combination of two or more different materials. Whose quality is superior than its constituents. Composite materials can be used not only for structural applications, but also in electrical, thermal and various other applications. FRP materials are widely used in various engineering industries because of their superior performance and tailor made properties.

FREE STATE WAY FINDING STRATEGY BASED MULTI- FEATURED AUTONOMOUS ROBOT IN INDUSTRY ENVIRONMENT

 

Authors: Harisha S K, Ramakanth P Kumar, M Krishna, S C Sharma

 

JERS/ Volume II/ Issue II/April-June, 2011/92-100

ABSTRACT
One of the longstanding challenges in Autonomous robot is the ability to navigate in complex environment, avoiding structured and unstructured environments. In case of multi behavior based autonomous robot, coordination and path finding is a very difficult task. The successful way of structuring the navigation task in order to deal with the problems is within behavior based navigation approach. Behavior coordination of autonomous robot is discussed in many papers. Some of the existing coordination methods are based on Mathematical model, Fuzzy Behavior Fusion, Context Dependent Blending etc. In this paper issues of multi behavior design, Fuzzy Based Perception Grouping (FBSP) and Free State Way Finding (FSWF) strategies are applied to the autonomous robot in order to get proper coordination of multi behaviors and for successful navigation. Fuzzy logic reasoning has been applied for individual behavior design as well as for the behavior coordination. In order to validate the algorithm generated using FSWF, hardware simulator have been designed and developed.

SPECTRAL SOLUTION OF STEADY STATE CONDUCTION IN ARBITRARY QUADRILATERAL DOMAINS

 

Authors:  Alavani Chitra R*, Joshi Pallavi A, S Pavitran, Bedekar Smita S

 

JERS/ Volume II/ Issue II/April-June, 2011/101-106

ABSTRACT
The Chebyshev spectral method is applied to steady state conduction problems with source terms. Arbitrary quadrilateral domains are considered. Both curved and straight boundaries are looked into. The Chebyshev derivative matrix is obtained in the physical space and utilised in obtaining the solution using the collocation method. The algorithm is tested for quadrilaterals with straight as well as curved boundaries. A general algorithm is also presented for an arbitrary curved quadrilateral. It can be seen that the algorithm yields spectral accuracy in all cases. In most cases, eight Chebyshev modes in each direction is sufficient to yield a high accuracy. The method is proposed with the idea of extending it to the equations of fluid flow.

EXPERIMENTAL STUDY OF ELECTRO DISCHARGE MACHINING FOR INCONEL MATERIAL

 

Authors:  Prof. D.V.Ghewade, Mr. S.R.Nipanikar

 

JERS/ Volume II/ Issue II/April-June, 2011/107-112

ABSTRACT
In this paper, the cutting of Inconel 718 material using electro discharge machining (EDM) with a copper electrode by using Taguchi methodology has been reported. The Taguchi method is used to formulate the experimental layout, to analyse the effect of each parameter on the machining characteristics, and to predict the optimal choice for each EDM parameter such as peak current, gap voltage, duty cycle and pulse on time. It is found that these parameters have a significant influence on machining characteristic such as material removal rate (MRR), electrode wear rate(EWR), radial overcut(ROC) and half taper angle. The analysis using Taguchi method reveals that, in general the peak current significantly affects the MRR and pulse on time significantly affects the EWR.

PERFORMANCE EVALUATION OF LEAN COMBUSTION TECHNOLOGY IN DIESEL ENGINE

 

Authors:  Puli.Danaiah, Puli.Ravi Kumar

 

JERS/ Volume II/ Issue II/April-June, 2011/113-118

 

ABSTRACT
The fuel consumption in an internal combustion engine forms a major portion of the total petroleum consumption in India and abroad. Hence it is imperative to use them with the highest possible efficiency in internal combustion engines. One of the latest methods to achieve the above goal is a lean mixture operation in an engine. The present work is planned to develop and evaluate the performance, combustion and emission characteristics of the lean burn fore stroke spark ignition engine. In practice the use of homogeneous lean mixtures in engine has been handicapped by several difficulties. The most serious one is that the flame propagation through mixtures becomes progressively slower as the mixture becomes leaner. The mixture distribution in an multi-cylinder engine is a problem because even small variation in mixture ratio on the linear side will strongly effect power output. Enhancement of lean combustion of homogeneous mixtures can be achieved by (i) using higher ignition energy (ii) providing high compression ratios (iii) creating high swirl in the combustion chamber and (iv) using methanol and its blends with gasoline.

AN INTELLIGENT SYSTEM FOR SELECTION OF MATERIALS FOR PRESS TOOL COMPONENTS

 

Authors: Kumar Shailendra

 

JERS/ Volume II/ Issue II/April-June, 2011/119-130

 

ABSTRACT
Selection of materials for press tool components is an important activity in the design of press tools in sheet metal industries. This paper investigates major considerations and presents an intelligent system for selection of materials of press tool components for sheet metal work. Knowledge for the development of the proposed system is acquired, analyzed, tabulated and incorporated into a set of production rules of IF-THEN variety. The system is coded in the AutoLISP language and loaded into the prompt area of AutoCAD. The system invites the user to enter required inputs and finally imparts intelligent advices related to material selection through the user interface. Knowledge base of the system can be modified depending upon the availability of new materials and advancement in technology. As the proposed system can be implemented on a PC having AutoCAD software, therefore its low cost of implementation makes it affordable to die designers and toolmakers working in small and medium size sheet metal industries. The usefulness of the proposed system is demonstrated through a sample run using an example of an industrial component.

LIQUEFACTION CHARACTERISTICS EVALUATION THROUGH DIFFERENT STRESS-BASED MODELS: A COMPARATIVE STUDY

 

Authors: P. Raychowdhury* and P. K. Basudhar

 

JERS/ Volume II/ Issue II/April-June, 2011/131-142

 

ABSTRACT
The paper presents a comparative study of the predicted response of a liquefiable saturated sand deposit of Nigata city under different seismic ground motion using three different stress based analytical models due to Finn et al. (1977), Liou et al. (1977), and Katsikas and Wylie (1982). The results are also compared with simplified methods that are adopted in the current design practice. It has been found that the models by Finn et al. (1977) and Katsikas and Wylie (1982) result in close predictions, whereas the predictions by Liou et al. (1977) are significantly different, particularly for predicting the rate of partial liquefaction for the chosen soil deposit and earthquake motions.

WEB BASED COUNSELING SYSTEM WITH ELECTRONIC PRESCRIPTION FOR RURAL AREA

Authors: Revati Shriram, Leena Sharma

 

JERS/ Volume II/ Issue II/April-June, 2011/143-148

 

ABSTRACT
The advances in Medical Science, Biomedical Engineering, Telecommunication and Information Technology are offering wide opportunities for improved healthcare. Telepsychiatry is the branch of Telemedicine, which allows effective way to increase access to psychiatric care for individuals living in underserved areas. Some areas in Asia have no medical facilities and proper mental healthcare is unavailable. Therefore, online counseling system is required. It can connect patients, psychiatrists, physicians, and other healthcare professionals through live interactive 2 way audio-video communication. This technology offers the best options for delivering healthcare for rural & geographically distant population spread across India and is used to provide patients with second opinion. The paper describes Web Based Counseling System with E-Prescription for Rural INDIA. The windows based system is constructed using Ajax software. The first step involved developing a prototype system; we repeatedly discussed system development with people in charge of a clinic. Next, we conducted a survey in 3 clinics and carried out interviews of 10 patients about the online counseling system; among them 7 patients were regular visitors of respective clinics and 3 patients were the first time visitors. We also discussed and analyzed the interviews

NRZ VS. RZ: PERFORMANCE ANALYSIS FOR FIBER-OPTIC CDMA

 

Authors: Jaswinder Singh

 

JERS/ Volume II/ Issue II/April-June, 2011/149-151

 

ABSTRACT
Non-Return-to-Zero (NRZ) and Return-to-Zero (RZ) are two basic formats in WDM optical communication systems. Over the years, many modifications to these two basic formats have been proposed. Since the system performance analysis of Optical CDMA systems is mainly degraded with the multiple access interference (MAI), hence the role of an optimum modulation format in the presence of MAI needs to be explored. In this paper, the comparative analysis of NZ and RZ is hence presented through simulation of a real-like optical CDMA system

DATA SECURITY IN OPTICAL CDMA SYSTEMS

Authors: Jaswinder Singh

 

JERS/ Volume II/ Issue II/April-June, 2011/152-154

 

ABSTRACT
Data security is one of the most crucial requirements in present day communication systems. While the digital systems rely on encryption techniques, the optical CDMA systems are inherently secure since their operation involves unique code assignment to the users. This is because of the fact that only the matched code receivers are able to decode the transmissions whereas the receivers with unmatched codes will not be able to retrieve any signal. In this paper, the different scenarios of breach of data security have been explored and the various techniques proposed for assuring the data security have been discussed.

QUALITY CIRCLE IMPLEMENTATION FOR MAINTENANCE MANAGEMENT IN PETROCHEMICAL INDUSTRY

 

Authors: N K K Prasanna

 

JERS/ Volume II/ Issue II/April-June, 2011/155-162

 

ABSTRACT
This paper deals with various aspects of Quality Circle and how improvements can be made by adopting practices of Quality Circle in petrochemical industries. The paper also presents a comparative discussion of various features of Quality Circle, Quality Improvement Group and Work Group/Project Team. The paper describes a case study of QC concept in a petrochemical industry which illustrates the effectiveness of QC approach.

PRODUCE ELECTRICITY BY THE USE OF SPEED BREAKERS

 

Authors: Shakun Srivastava , Ankit Asthana

 

JERS/ Volume II/ Issue II/April-June, 2011/163-165

 

ABSTRACT
Electricity in India? Is a big problem which is faced by people who resides in the country. Generating electricity by speed breakers is innovative and useful concept. Electricity is the form of energy, Electricity is a basic part of nature and it is one of our most widely used forms of energy. We get electricity, which is a secondary energy source, from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources. Many cities and towns were built alongside water falls that turned water wheels to perform work. Before electricity generation began slightly over 100 years ago, we use kerosene lamps, , and rooms were warmed by wood-burning or coal-burning stoves. Direct current (DC) electricity had been used in arc lights for outdoor lighting. In the late-1800s, Nikola Tesla pioneered the generation, transmission, and use of alternating current (AC) electricity, which can be transmitted over much greater distances than direct current. Tesla's inventions used electricity to bring indoor lighting to our homes and to power industrial machines. Electricity generation was first developed in the 1800's using Faradays dynamo generator. Almost 200 years later we are still using the same basic principles to generate electricity, only on a much larger scale.