Free Essay

Serial Communication over Parallel

In: Computers and Technology

Submitted By sachinjnd
Words 2963
Pages 12
EEL201 Term Paper: Serial Communication Over Parallel


Serial Communication Over Parallel
Sachin Garg Indian Institute of Technology, Delhi-110016 E-mail:
 Abstract—Communication is the essence of today’s technologically advanced world. The two most basic methods of digital communication are: Serial and Parallel. Parallel communication involves multiple wires running parallel to each other and can transmit data on all the wires simultaneously. However, Serial communication requires a single wire for transferring data bits one at a time. A natural question arises out of human curiosity: which one of the two methods is better. This term paper discusses these two methods, their various applications and the advantages of the Serial Communication method over the Parallel one. Index Terms—Parallel Communication, Serial Communication UART, RS-232 DTE, Synchronous, Asynchronous.

Parallel counterpart have been resolved. Although the Parallel Transmission Method is still used within internal buses and for devices such as printers, but the latest devices, ports and technologies are mostly based on Serial Techniques. For example - Universal Serial Bus and WAN, both make use of the Serial Type Data Transmission.

II. TERMS USED IN DATA COMMUNICATION A. Transmission Distance The transmission distance of a communication signal is the length of path the signal travels as it goes from transmitter to the receiver. B. Data Terminal Equipment (DTE) Data Terminal Equipment (DTE) is a device or equipment that acts either as a source or as destination during the transmission of data signals. A DTE controls the communication channel. However, DTEs don‟t directly communicate with each other. For this purpose, the DTEs need Data Communication Equipment (DCE). Some examples of DTEs are: computer, printer, dumb terminals, file and application servers etc [2]. C. Data Communication Equipment (DCE) Data Communication Equipment (DCE) is a term used for the devices and connections of a communication network which transmit or receive data signals, thereby, completing the communication network. DCEs also help in synchronization with a clock rate in serial communication. With the use of DCEs, DTE doesn‟t have to know how the data is sent or received. The details of the communication over the network are left with DCEs. A modem is a very good example of a DCE, it works as a translator of analog to digital signals and vice-versa. Other examples include satellites, ISDN adapters etc [2]. D. Baud Rate The Baud Rate of a data communication system is a measurement of transmission speed. It is the number of symbols transferred per second. It actually represents the number of bits that are actually being sent over the serial link including the overhead bits Start, Stop and Parity that are also transferred in asynchronous serial communication [3].



HE communication technology has gained very much importance over time and there are a lot of researches going on all over the world in this area of digital electronics. The big companies like- Apple and IBM are coming up with fastest of the computers ever made. Intel is producing highly efficient micro-processors using the latest Thunderbolt Technology which dramatically increases the data transfer performance giving up to 10Gbps bi-directional speed [1]. All of these tremendous innovations have possible because of the advancement in the data transmission methods. Basically, there are two different methods of data transmission: Serial and Parallel. Serial transmission involves a single stream of data being transmitted over a single channel whereas parallel transmission is able to transmit several streams of data along multiple channels. To achieve fastest transmission technology, it is very important to analyze the effectiveness of both the methods. At first site, it seems that the Parallel Transmission is faster because of the multiple bits transmission at a time. The earlier communication standards were more inclined towards the Parallel Transmission Architecture but recently, there is a shift towards the Serial Techniques as latest technology and research in the Serial Transmission domain has allowed it to become even faster than the Parallel Transmission. Also, many problems in the
Manuscript received November 10, 2012. Author Sachin Garg is a Sophomore Undergraduate in Indian Institute of Technology, Delhi-110016 and is pursuing a B.Tech. degree in Electrical Engineering (Phone: 09811604263; E-mail:

EEL201 Term Paper: Serial Communication Over Parallel E. Handshaking The process by which DTEs and DCEs initiate communication. Handshaking begins when one device sends a message to another device to establish a communication channel. After that, several messages are sent back and forth between the devices that enable them to agree on a certain communication protocol [4]. 1. DTE requests DCE to send data (RTS). 2. DCE indicates DTE when ready and clear to send data (CTS).

2 automation, Internet and ISDN are a few of its major applications [6]. How it works: In this type of data transmission, the digital information is exchanged across the communication network using one wire only. Unlike parallel communication, only one data bit is sent across the link at a time. The electronics devices are able to communicate with the outside world using Serial method of Communication. The communication media in serial transmission is mostly wire based but can be optical or radio based also. The digital information flows as a single stream of data. However, the microprocessors inside the electronic gadgets process the data in bit-parallel mode, so a transmitter is required to convert parallel data to serial form at the transmitter end, and to convert from serial to parallel at the receiver end.

III. PARALLEL COMMUNICATION The parallel communication technology is used over very short distances, typically inside the computer itself and to printers. The parallel data transmission method, together with the connector, was first developed by Centronics and used by IBM in its first Personal Computer [5]. How it works: In this type of data transmission, the data information is exchanged across the communication network using multiple wires. Instead of squishing the bits together, more wires are used to send the bits simultaneously. So, there are several data streams instead of just one. Since multiple wires are used for transmission, this method is expensive. A constant clock signal is sent over a separate wire within the parallel cable for the purpose of handshaking. Also, “as the length of the cable gets longer, the synchronization timing between the multiple channels becomes more sensitive to the distance” [15].

Fig. 2. Simple Two-wire Line for Bit-Serial Data Transmission [6].

The D-shaped 9-pin connection-port is a very nice example of Serial Data Transmission port. It uses two loops of wire for the communication of data. Also, there are additional wires to control the flow of information. However, in any given direction, the data still flows over a single wire. Other examples include USB, FireWire, SATA and PCI Express. A UART (Universal Asynchronous Receiver/Transmitter) is used in the serial transmission technology. The UART: What is it and how it works A UART (Universal Asynchronous Receiver/Transmitter) is the microchip which is programmed such that it is able to control a computer‟s interface to the attached serial devices. Some internal modems also have their own UART. Looking down from a worm‟s eye view, UART actually provides the computer with the RS-232 Data Terminal Equipment (DTE) interface so that it can talk to and exchange data with the modems and other serial devices [7]. RS-232 DTE RS-232 is abbreviated for Recommended Standard-232. This is a standard interface that is approved by the Electronic Industries Association (EIA) for connecting serial devices. In other words, RS-232 is a long established standard that describes the physical interface and protocol for relatively low-speed serial data communication between computers and related devices [8].

Fig. 1. Parallel Data Transmission.

For example, in the case of a 25-pin parallel port, eight bits of data is transferred simultaneously through eight datacarrying wires.

IV. SERIAL COMMUNICATION The serial communication technology is increasingly being used for the transmission of digital data across the communication networks. A very large number of latest communication networks apply this method of data transmission. Computer networks for office communications, field-bus systems in process, building and manufacturing

EEL201 Term Paper: Serial Communication Over Parallel As a part of this interface, the UART also performs the following operations: 1) It converts the parallel-data bytes received from computer micro-processor chips into a single serial bit stream for transmitting the signal. 2) At the receiver‟s end, it performs just the reverse of above operation, i.e., converts serial bit stream back to the form compatible with micro-processor chips. 3) It also adds a parity bit (if selected for so) on outbound transmissions, and at the receiver‟s end, it checks the parity of incoming bytes and discards the parity bit. 4) It adds and transmits start and stop delineators during transmission and strips them from inbound transmissions. 5) It handles any interruptions caused from the keyboard and mouse (which are serial devices with special ports). 6) It can also handle other types of interruptions and can help in synchronizing computer‟s speed of operation with devices speed [7].

3 the receiver must know when to read the next bit coming from the sender‟s end. For handshaking, a clock is shared between the sender and the receiver. So, some extra wiring and control circuits are required to share the clock. Also, when there is no data-bit to be transmitted, a fill character is used, so that data is always being transmitted. Some of the examples where this is used are: phone calls, text chat, Skype etc [10].

VI. ASYNCHRONOUS SERIAL TRANSMISSION In this method, no clock signal is used by the sender. But the receiver must be having a way to distinguish between the valid data bits and noise. So, special bits are added by the sender to each word for the purpose of handshaking. These special bits include- a start bit, parity bit (may or may not be) and a stop bit. Thus, sometimes also called Start-Stop Communication. 1. Start bit - indicates the beginning of the data word. 2. Stop bit - indicates the end of the data word. 3. Parity bit - added for error detection (optional) [11]. PS2 ports on the computer use this type of communication to connect with keyboard and mouse.

VII. SERIAL COMMUNICATION VS PARALLEL The communication channels or links across which the computers and other related gadgets talk to one another may be either parallel or serial. A serial link transmits a single stream of data whereas a parallel one is able to transmit several streams of data along multiple cables or channels. Looking down from a bird‟s eye view, it seems that a parallel link must be superior to a serial one, because it can transmit more amounts of data on each clock tick. However, in actual reality, it is the serial links that achieve a higher Baud Rate as compared to the parallel ones because serial links can be clocked faster than the later ones due to a number of factors. Some of them are: A. Clock Skew Superficially, the speed of parallel link is equal to the number of channels used multiplied by the bit rate of each channel; so eight channels imply, eight times faster. But, in practice, clock skew reduces the speed of every channel to the slowest of all the channels. Clock Skew is the phenomenon due to which there is a time difference in the clock arrival time at different components in the circuit. “For two sequentiallyadjacent registers Ri and Rj with clock arrival times at register clock pins as TCi and TCj respectively, then the clock skew can be defined as: TSkew i, j = TCi - TCj The clock skew can be positive or negative” [12]. B. Isolation The cables used in a serial connection are fewer (e.g. wires/fiber) and hence occupies less space. This extra space is

Fig. 3. DE9 connector (DB9 connector), commonly used for serial ports (RS-232) [9].

During the serial data communication, the receiver must know whether the received signals are valid or not. For this purpose, the transmitter and the receiver must be synchronized. Based on how this is done, the serial communication can be further sub-divided into two categories: 1. Synchronous Transmission 2. Asynchronous Transmission

V. SYNCHRONOUS SERIAL TRANSMISSION In this method, each end of the communication network response before initializing a new conversation. The receiver‟s response is either Success or Resend [8]. Success means the receiver is ready to receive next piece of information. Whereas Resend implies some problem occurred and asks the transmitter to send the previous data packet again. Similarly,

EEL201 Term Paper: Serial Communication Over Parallel used for providing better isolation of the channel from the surroundings [13]. C. Crosstalk Crosstalk creates interference between the parallel lines, and this effect worsens as the length of the communication channel increases. Crosstalk is any phenomenon due to which a signal transmitted on one channel or circuit creates an undesired effect in the neighboring channel or circuit [14]. Advantages of Serial Data Transfer over Parallel: 1) Transmission Distance: The length of the serial cables can be much larger than the parallel cables. This is because a parallel port transmits a „0‟ as 0 Volts and a „1‟ as 5 Volts whereas a serial port transmits a „0‟ as -3 to -25 Volts and a „1‟ as +3 to +25 Volts [7]. So, a maximum swing of 50 Volts is allowed in the serial transmission compared to just 5 Volts in the parallel transmission. Since the maximum swing is very less in parallel, so cable loss causes a lot of problems. But, in serial communication, maximum swing allowed is much higher providing more flexibility. 2) Economical: The number of cables used in serial transmission is very less as compared to the parallel one. For example, in a Null Modem Configuration, the application of serial communication (3 core cables required) is going to be a lot cheaper than the later one (where 19 or 25 core cables are required) [7]. 3) Space Efficient: Since less cables are used in serial data transmission, therefore, it is much more space efficient than the parallel method of data transmission. 4) Easier to Decipher: Infra-red devices are based on serial data transmission method. It is very difficult to decipher eight bits (as in parallel transmission). Therefore, former method is used in which only one-bit data is transmitted at a time. The first infra-red, IrDA-1 was capable of 115.2k baud and it was interfaced into a Universal Asynchronous Receiver/Transmitter (UART) [7]. 5) Reduces Pin Count: Micro-controllers are in quite popularity nowadays. Most of these are based on the Serial Communication Interfaces (SCIs) which are used to communicate with the outside world. Serial Communication reduces the pin-count of these micro-controllers as in most of them, just two pins are commonly used, Transmit Data (TXD) and Receive Data (RXD) instead of minimum eight pins if eight-bit parallel method is used [7]. VIII. CONCLUSION


Many advances have been developed in the Serial Communication Techniques over the last couple of years and researches are still going on in this domain. Many latest technologies providing high speed data transmissions are based on Serial Techniques. WANs also use Serial Transmission over long distance communication. Super speed USB 3.0 providing transfer speed as high as 5 Gbps is another example. Also, the latest Thunderbolt Technology developed by Intel with bi-directional 10Gbps speed, which can transfer an entire HD movie within seconds, uses single cable transmission. “Enhancing performance with innovative design, Thunderbolt technology combines PCI Express and DisplayPort I/O protocols onto a single highly-efficient metaprotocol” [1]. So with the advancements, Serial Transmission outruns the Parallel counterpart. ACKNOWLEDGMENT I take this opportunity to thank Prof. Shouri Chatterjee and Prof. Anuj Dhawan for exemplary guidance, monitoring and constant encouragement throughout the course. The blessing, help and guidance given by them time to time shall carry me a long way in the journey of life on which I am about to embark. I also thank my friends and family for their help, encouragement and constant support. REFERENCES
[1] "Thunderbolt™ Technology for Developers." Internet: [Nov. 6, 2012]. "Principles of Data Communications: Basic Concepts and Terminology." Internet: [Nov. 4, 2012]. A. Awadhi. "What is Serial communication?" Internet: n.pdf [Nov. 5, 2012]. "Handshaking." Internet:[Nov. 9, 2012]. "Parallel Communications Explained." Internet: [Nov. 4, 2012]. "Serial Data Transmission." Internet: [Nov. 6, 2012]. B. R. Mundari, P. Priyadarshan. "Serial Communication By Using UART." B.Tech. thesis, National Institute of Technology, Rourkela, India. Available: [Nov. 6, 2012]. "Introduction to Serial Communication." Internet: [Nov. 2, 2012]. "D-sub 9 Pinout." Internet: [Nov. 4, 2012]. "Synchronous Communication." Internet: 20Communication [Nov. 5, 2012]. "Serials Communications." Internet: ons.pdf [Nov. 2, 2012]. "Clock Skew." Internet:, Sep. 16, 2012 [Nov. 8, 2012]. "Serial Communication." Internet: [Nov. 7, 2012]. "Crosstalk (electronics)." Internet:, Oct. 16, 2012 [Nov. 2, 2012]. “Serial and Parallel Transmission.” Internet: [Nov. 2, 2012].



[4] [5] [6] [7]

[8] [9] [10]


[12] [13] [14] [15]

Similar Documents

Free Essay

Parallel Kinematic Machine

...1 INTRODUCTION 1.1 INTRODUCTION A parallel mechanism is a closed-loop mechanism of which the end-effector is connected to the base by a multitude of independent kinematic chains. Generally it comprises two platforms which are connected by joints or legs acting in parallel. In recent years, parallel kinematic mechanisms have attracted a lot of attention from the academic and industrial communities due to their potential applications not only as robot manipulators but also as machine tools. The dream of all developers in Machine Tools has always been to combine the flexibility and envelope of the robots with the accuracy and stiffness of traditional Machine Tools. In the last 20 years the focus of this development has been Parallel Kinematics Machines so called PKM. This technology means that the motions in X, Y and Z are performed by three or more parallel axis that gives an outstanding stiffness and accuracy with a maintained flexibility and envelope. Generally, the criteria used to compare the performance of traditional serial robots and parallel robots are the workspace, the ratio between the payload and the robot mass, accuracy, and dynamic behavior. In addition to the reduced coupling effect between joints, parallel robots bring the benefits of much higher payload-robot mass ratios, superior accuracy and greater stiffness; qualities which lead to better dynamic performance. The main drawback with parallel robots is the relatively small workspace. 1.2......

Words: 6225 - Pages: 25

Premium Essay

Serial Killers and the Media

...Serial Killers and the Media Maureen McCollom Kaplan University Deviance and Violence Professor Major March 26, 2013 Abstract Serial murders are not just part of the United States they also happen globally. There are many investigative tools that are used when working a serial murder case and we will discuss some of those. We will also discuss the problems with the media when it comes to serial murders. We will also talk about how the criticism of the public and media can affect serial murder cases. The crime of serial murder is not just one that in the United States it is a problem that happens globally. In the US we have the help of the Behavioral Analysis Unit as well as the FBI when working a case in any jurisdiction. To help law enforcement and investigators learn new techniques on how to solve these crimes a symposium was held for two days in 2008 to teach them new techniques. In attendance at this conference were mental health experts, scholars, media experts who have been studying serial murders for yeas and investigators in law enforcement field. The conference was held at INTERPOL headquarters, there were delegates from thirty-seven different countries in attendance at the conference. When working on a serial murder there needs to be more cooperation with other countries when working the cases. While most serial murders will stay within their comfort zone or home town, some will travel from place to place as well as out of the country to commit...

Words: 1163 - Pages: 5

Free Essay

Laser Communication

... LASER COMMUNICATION SYSTEM (Light Amplification by Stimulated Emission of Radiation) Abstract: Laser communication is one of the key areas in wireless Communications. They work only under clear line-of-sight conditions between each unit, but they eliminate the need for securing right of ways, buried cable installations and no government licensing is necessary. Free space laser communications systems can be quickly deployed since they are small and do not need any radio interference calculations. Additionally, no spectrum fees have to be paid. This paper includes analysis, optimization, design and system level development of signal transformation between satellites or any two sources. Which work similarly to fibre optic links, except the beam is transmitted through free space. The carrier used for the transmission signal is typically generated by a laser diode. Two parallel beams are needed, one for transmission and one for reception. INTRUDUCTION: Laser Communication is one of the emerging areas of wireless communication system. Due to its low noise ratio makes its one of the well suited communication medium for exchange of information. Currently laser commutation is adopted in satellite communication for space research activities and due to its efficiency on low noise ratio, inexpensive, low power and its flexibility and its resistance to the radio interferences makes laser communication as one of research area in wireless communication. In this process, this paper...

Words: 2114 - Pages: 9

Premium Essay

Serial Killer

...Edited by Stephen E. Schmid Hunting – Philosophy for Everyone: In Search of the Wild Life Edited by Nathan Kowalsky Christmas – Philosophy for Everyone: Better Than a Lump of Coal Edited by Scott C. Lowe Cannabis – Philosophy for Everyone: What Were We Just Talking About? Edited by Dale Jacquette Porn – Philosophy for Everyone: How to Think With Kink Edited by Dave Monroe Serial Killers – Philosophy for Everyone: Being and Killing Edited by S. Waller Dating – Philosophy for Everyone: Flirting With Big Ideas Edited by Kristie Miller and Marlene Clark Gardening – Philosophy for Everyone: Cultivating Wisdom Edited by Dan O’Brien Motherhood – Philosophy for Everyone:The Birth of Wisdom Edited by Sheila Lintott Fatherhood – Philosophy for Everyone:The Dao of Daddy Edited by Lon S. Nease and Michael W. Austin Forthcoming books in the series: Fashion – Philosophy for Everyone Edited by Jessica Wolfendale and Jeanette Kennett Coffee – Philosophy for Everyone Edited by Scott Parker and Michael W. Austin Blues – Philosophy for Everyone Edited by Abrol Fairweather and Jesse Steinberg Edited by S. Waller SERIAL KILLERS PHILOSOPHY FOR EVERYONE Being and Killing Foreword by John M. Doris A John Wiley & Sons, Ltd., Publication This edition first published 2010 © 2010 Blackwell Publishing Ltd except for editorial material and organization © 2010 S. Waller Blackwell Publishing was acquired by John Wiley & Sons in February 2007. Blackwell’s publishing program has been......

Words: 90119 - Pages: 361

Free Essay

Parallel and Series Ports

...Troubleshooting * Printers Ports * Serial ports transmit data 1 bit at a time. They are usually male and have 9-25 pins. * Parallel ports transmit data 8 bits at a time and are generally female with 25 pins. * Game ports have 15 pins laid out in two rows (female). * Video monitors have 15 pins but are laid in three rows (male) Connectors * Early mice used a serial connector and keyboards used a 5 pin DIN connector. * Modern mice and keyboards use a PS/2 technology which is a much smaller 6 pin DIN connector or a USB or wireless connection. * NIC- Network Interface card uses a RJ-45 connector. * The NIC is responsible for connecting a computer to local and distant networks or the internet. * It also converts parallel communication used by the motherboard system into serial communication used by the network cable. Modem, Video and USB * It is the slowest possible way of connecting to the internet. * Its standard speed is 56Kbps although v.92 standard supports faster speed. * They are responsible for converting the analog signal from the phone line into a digital format a computer can use. * It also converts the digital signal back to analog when sending a transmission. They connect using a RJ-11 connector. * Modern computers come with two types of video ports , the VGA (analog interface) D-type, 15pins, 3 rows and the DVI (digital visual interface) * USB- Universal Serial Bus are hot swappable. USB1 transmit......

Words: 906 - Pages: 4

Free Essay


...ABSTRACT The greed for money will make people commit Haynes crimes, for a 46 yr old Dutch women from the Netherlands was a motive to become a serial killer. Maria Catherina Swanenburg had love for money where she killed her parents, family members and other vulnerable people she cared for by poisoning with arsenic poison. Swanenburg was known as Vin der Linder by family and friends. She was a very affectionately given the nick name of “ Goeie Mie “ which means in Dutch “ Good Me “. She was given that nick name which she got by taking care of children and sick, fragile people in the neighborhood. Maria Catherina was born September 9, 1839 in the Netherlands. Swanenburg was the daughter of Clemens Swanenburg and Johanna Dingjon. It was speculated that after the deaths of her first two daughters she became heartless. Maria began her killing spree by poisoning her parents in 1880. She was able to keep their life insurance as well as the inheritance. However that opened up more greed for money. So she began poisoning the people she was caring for, she would mix the arsenic with the food or drinks of her victims. She would insure them and then poison them. Her rational was that she deserved to keep the inheritance as well as the life insurance money because she cared for these poor ill people. Swanenburg became bolder over time. The money she collected was just not enough for her. However she didn’t have a chance to spend any of the money because she continued to poison......

Words: 516 - Pages: 3

Premium Essay

Serial Killers

...In the last three decades the USA has been troubled by an approaching problem, the serial killer. A serial killer is a person who kills a number of people, usually considered over five, with a cooling off period between each murder, usually one murder at one given time). Two murders at one time occasionally happen and these murders may go on for a period of months or years until the killer is caught. Throughout the last three decades the US serial killer rate has risen 94% and it is estimated that by the next millennium it will claim an average of 11 lives a day. Serial Murder is an epidemic; there are at least 35 serial killers active in the USA today who claim one third of the annual murder rate. The USA has 6% of the world's population yet it has three quarters of all serial killers. Not only are serial killers appearing in more numbers in the US but also all over the world countries are terrorized by serial killers, which are appearing in more numbers year and year after. KILLER TRAIT: A serial killer is a typical white male, 20-30, and most of them are usually in the USA. Their main motives are sex (even though the act of sex may or may not take place), power, manipulation, domination and control. The sex motive is usually rape for an organized killer and sadism for a disorganized killer. They act in a series of 5 or more murders with a cooling off period between each murder. Serial killers can go on for months and years before they are usually caught. The victim is......

Words: 4193 - Pages: 17

Premium Essay

Serial Killers

...I. Introduction Serial Killers are the group of people who kill, kill and kill over a longer period of time without being caught or stopped. Unlike mass murderers, who may kill many people at one time. Serial Killers are a different breed. Serial killers usually have reasons for killing, they just don't go out and kill anyone (the majority). A serial killer will plan out where, when, why, and how before they actually kill. Many enjoy cannibalism, necrophilia, and keep their trophy - like body parts as reminders of their work. There violent behavior is usually directed against women and children. In most cases, if a serial killer tortured his victims inhumanly than the killer himself has probably had a very disturbed childhood. II. Body ''I didn't want to hurt them,I only wanted to kill them.'' This is a quote from David Berkowitz the Son of Sam. David Berkowitz and all of the other serial killers tend to think in unique ways. Dahmer killed various ways and then hacked his victims into several pieces, dumping the bodies into vats of acid, and Gacy molested little boys before strangling them and dumping them into the crawl space under his home. They often tend to have interesting stories behind their killings because they often see and hear things that the normal person doesn't. Schizophrenia is a common source are associated with psychotics. As we examine childhood abuse as a possible key to the serial killer's behavior, we must remember that many children have suffered......

Words: 395 - Pages: 2

Free Essay

Dynamic Modelling of Parallel Manipulator

... “Newton Euler Strategy for the Dynamic Analysis of 3-DOF Parallel UPU Manipulator” Abstract This projects aims to describe the dynamic analysis of the 3-DOF Parallel UPU manipulator. The 3 DOF UPU is a parallel manipulator in which the U and P notations are for universal and prismatic pairs respectively, is a well-known manipulator that provides the platform with three degrees of freedom of pure translation, pure rotation or mixed translation and rotation with respect to the base, according to the relative directions of the revolute pair axes. The pure translational parallel 3-UPU manipulators have received a great lot of attention. Over the years many studies have been reported in the literature on the kinematic analysis, workspace optimization, singularities and joint clearance influence on the platform accuracy of this manipulator. However, the evaluation of the dynamic modelling of the parallel manipulators based on the two most famous methods i.e. Newton- Euler and Lagrange’s method have not been clearly discussed so far. Therefore, this project tries to throw light on this area and covers the Newton Euler Strategy for the calculation of the dynamic model of the 3 DOF UPU Parallel Manipulator. 1. Introduction Over the last few decades the parallel manipulators have attracted the attention of lot of researchers because of their complementary characteristic with serial manipulator. The word 'Parallel’ which is used here is to point out is not in the......

Words: 2803 - Pages: 12

Premium Essay

Serial Killers

...and death are twisted into a passion to kill. Otherwise a “typical” individual, serial killers turn to violence and death in search of power over others, and to explore their fatal addiction to their monstrous thrills. Most of society views serial killers as they are portrayed on television. There’s Dexter, the handsome serial killer who, while leading a normal life, takes it upon himself to rid all of the “bad guys” in the world in order to fulfill his need to kill. Then there’s Freddy Kruger, a disfigured dream stalker who uses a glove armed with razors to kill his victims in their dreams, causing their deaths in the waking world as well. Just to name a few others, there's also The Jigsaw Killer, Dr. Hannibal Lecter, Leatherface, Michael Meyers and the infamous Chucky. All of these characters are created to exaggerate something that is not only feared in movie theaters, but in real life as well. But what exactly makes a serial killer? While many of these movies and television programs try and make our minds believe that fiction is reality, there are no such things as ‘dream stalkers’ and talking dolls. A real-life serial killer can be distinguished (not by a scary masks) through the many distinctive patterns in their social and mental behavior, unusual childhood, murder periods, and Modus Operandi; all of which are fashioned in different ways to create a cold blooded murderer. Serial Killers are normally classified by their social and organizational skills.......

Words: 1565 - Pages: 7

Premium Essay

Business Communication Parallels in the Movie Pretty Woman

...Executive Summary This report seeks to explore communications at Republic Bank Trinidad Ltd. Communications would include internal(interdepartmental, intradepartmental, executive communication) and external. These communication would encompass formal and informal methods. Interdepartmental Communication Interdepartmental communication is very important to all organizations. Republic Bank Ltd as a bank would have to foster efficient communication as financial information need to be timely and accurate. On a daily basis information would need to be communicated across departments for the running of a bank. Information on a customer’s transactions may be requested by a loans officer. Communication would in most cases would be formal but some cases it would be informal and later documented to be formal. Intradepartmental Communication Within departments information needs to be shared so that departments do not have contradicting information. In the department managers would employ downward communication, through instructions, to employees while employees would engage in upward communication, through reports to managers. Formal communication would be most used through manager to employee relations. Whereas informal communication would more be conducted from employee to employee. Executive Communication Executive communication occurs when information from senior manager disseminates down the chain of command. Executive communication seeks to transfer senior management’s......

Words: 1306 - Pages: 6

Free Essay


...Signaling Method for a Bidirectional Parallel Peripheral Interface for Personal Computers IEEE Computer Society .- Sponsored by the Microprocessor and Microcomputer Standards Committee h Published by the Institute of Electrical and Electronics Engineers, Inc., 345East 4Tth Street, New York, N y lwlz USA. lEEE December 2, 1994 SH 1 7335 Authorized licensed use limited to: UNIVERSITY OF VICTORIA. Downloaded on July 29,2010 at 20:21:17 UTC from IEEE Xplore. Restrictions apply. THIS PAGE WAS BLANK IN THE ORIGINAL Authorized licensed use limited to: UNIVERSITY OF VICTORIA. Downloaded on July 29,2010 at 20:21:17 UTC from IEEE Xplore. Restrictions apply. Recognized as an American National Standard (ANSI) IEEE Std 1284-1994 IEEE Standard Signaling Method for a Bidirectional Parallel Peripheral Interface for Personal Computers Sponsor Microprocessor and Microcomputer Standards Committee of the IEEE Computer Society Approved March 30, 1994 IEEE Standards Board Approved September 2, 1994 American National Standards Institute Abstract: A signaling method for asynchronous, fully interlocked, bidirectional parallel communications between hosts and printers or other peripherals is defined. A format for a peripheral identification string and a method of returning this string to the host outside of the bidirectionaldata stream is also specified. Keywords: bidirectional parallel communications, computers, interfaces, PCs,......

Words: 34986 - Pages: 140

Premium Essay

Parallel Journeys

...Book Review Parallel Journeys Parallel Journeys, by Eleanor Ayer with Helen Waterford and Alfons Heck, compares the life of two young people in Germany during the rise of Hitler and the outbreak of World War II. They were born within sixty miles of each other, but their lives took dramatically different paths. Alfons, is a boy who grew up on a farm in Germany. When Hitler came to power he became involved with the Hitler Youth. Alfons grew up on a farm but was a Nazi boy who became a commander at age sixteen. This book truly depicts Hitler's impact and influence on the youth of Germany. Alfons was brainwashed by Hitler's promises, a full pledged Nazi youth is how it is presented in the book he participated in all rallies. He started his training to become the future of Germany and eventually of the world. There he learned discipline and order. He trained to become a soldier and he learned the ways of warfare. He was taught to be a follower of anti-Semitism and was told to hate the Jewish people. He along with millions of Nazi’s believed that they were the reason for Germany's problems. As years went by, Alfons rose through the ranks of the military until the end of the war where realized what atrocities had been committed, he than took off his uniform and went on to help people. On the other side of the spectrum we have Helen Waterford a young Jewish girl who grew up in Frankfurt, Germany. She married Siegfried Wohlfarth and moved to Amsterdam because of tension......

Words: 2271 - Pages: 10

Free Essay

Parallel Postulate

...Elliptic Geometry The parallel postulate (a.k.a. Euclid’s fifth postulate) in Euclidean Geometry states that if one cuts a line segment with 2 lines, and the interior angles add up to less than 180 degrees, then the two lines will eventually meet if extended infinitely (Euclid’s parallel postulate exact words: if a line segment intersects two straight lines forming two interior angles on the same side that sum to less than two right angles, then the two lines, if extended indefinitely, meet on that side on which the angles sum to less than two right angles). Mathematicians such as Aristotle tried to prove this prove the parallel postulates, but they always ended up using the postulate itself in proving it, causing great controversies. In the late 19th century, mathematicians began to question if the postulate was true, which gave rise to the Non-Euclidean geometries. Elliptic geometry is a form of Non-Euclidean Geometry. It is different from Euclidean Geometry because it replaces the parallel postulate with the statement, "through any point in the plane, there exist no lines parallel to a given line” (there are basically no parallel lines), and because it modifies Euclid’s second postulate (there are no infinate lines in elliptical geometry). Bernard Riemmannian, the man who founded Elliptical (a.k.a. Riemmanian Geometry) Geometry had a lecture in 1854 discussing the ideas currently called manifolds, Riemmanian metric, and curvature. He also made many Non-Euclidean......

Words: 422 - Pages: 2

Premium Essay

Serial Killers

...Serial Killer Psychology By Anna Davis Criminal psychology refers to the study of the mental and behavioral characteristics of people who break laws established by local, state, national or international governments. Some criminal, or forensic, psychologists focus their research on serial killers -- men and women who murder a large number of people over an extended period of time — typically months or years. What constitutes a serial killer is open to interpretation. In the United States, Congress has defined a serial killer as someone who murders a minimum of three or more people. By definition, a cooling-off period separates the murders, making them appear random or unconnected. The victims — often prostitutes, runaways or other vulnerable populations — rarely know their killer and may serve as a symbol that triggers the attack. In other words, a serial killer's motive tends to be psychological, not material. Understanding what goes on — or gets turned off — in a serial killer's mind is the ultimate goal of scientists who specialize in this area of psychology. You might think the field is relatively new, but it dates back to at least the 19th century, when psychologists tried to develop a profile of the mysterious and elusive Jack the Ripper. Antisocial Personality Disorder vs. Psychopathy Mental health professionals use the Diagnostic and Statistical Manual of Mental Disorders (DSM), developed by the American Psychiatric Association, to understand the......

Words: 1547 - Pages: 7