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Mexicoââ¬â¢s Economical Crisis, Facts and Remedies Free Essays
Mexico is the most exceptional and created country in the Latin America, with a populace more than 96 million and per capita salary about $3...
Thursday, October 31, 2019
Customer Satisfaction and Loyalty of TESCO Essay
Customer Satisfaction and Loyalty of TESCO - Essay Example Tesco PLC is a public limited company in the retail industry and its headquarters is in the United Kingdom. Tesco is a general merchandise and British multinational grocery retailer. After Wal-Mart, it is the second largest retailer in terms of profit margins and is even the second largest retailer in terms of revenue growth in the worldââ¬â¢s retail industry. Jack Cohen in 1919 invented the company as a chain of market stalls. The name of the brand ââ¬ËTescoââ¬â¢ appeared in the shipment of tea that Cohen had purchased. The supermarketââ¬â¢s store that was about 500 in the 1990s is now approximately about 6350 located in various locations. Tesco expanded its business very rapidly and has a market share of about 30%. The countries in which the company has entered and is operating brilliantly are UK, USA, Thailand, Malaysia, Mainland China, Hungary, Czech Republic, Japan, Republic of Ireland, South Korea, Poland, Turkey, etc. The main idea behind the research study is to a nalyze the customer satisfaction and customer loyalty at Tesco. Customers are the most important factor behind the success or failure of a company. It is very much important that the organization takes effective measures to satisfy the customers and build a brand loyal customer base that would generate high revenues for the firm. Tesco through its market expansion strategy has become the market leader in UK retail industry. It has enhanced on its strengths and explored the possible opportunities and developed some innovative strategies to acquire the maximum percentage of the market share.
Tuesday, October 29, 2019
The NSW English k - 6 Syllabus Essay Example | Topics and Well Written Essays - 1500 words
The NSW English k - 6 Syllabus - Essay Example It is believed that language goes beyond tangible meanings and explores the meanings of less tangible. In the education context, language is vital for comprehensive and utilization of knowledge. Stone, et al (2004) also noted that language is used to solve problems as a tool through its application in both written and spoken words. In fact, language is used as a learning tool which aids understanding. In light with these deliberations, language is viewed as a vehicle for educational development, which is categorized among the most crucial components for the acquisition of knowledge (Raban, Brooks, and Wolfendale 1995). Development is a necessity in learning, and which is facilitated by language through interaction and socialization. The verbalization of both personal and vicarious experience makes individuals evaluate and structure representations of reality. The role of language in learning Characteristically, children go to school with some degree of commonsense understanding of th eir environment. Once in school, children start engaging with books and other children both of their age and older children and even adults. This forms a distinction between utterances and meanings of things said at home and ones made at school. Studies have enumerated the importance of language in education, with many citing that when children learns a language, they not only engage in one kind of learning, but also ensures that, through learning language, they learn how to mean (Raban, Brooks, and Wolfendale 1995). It is also apparent that the language enables students to focus on the object of learning and distinguish it crucial features. Language is critical in structuring studentââ¬â¢s awareness in order to become intellectually aware of learning. Language also makes meaning. The ability of teachers and students to negotiate to bring out meaning is well articulated through language (National Languages & Literacy Institute of Australia 1993). Language widens a, shared common ground between teachers and students. It is believed that there are specific conditions required for the learning of a specific object of learning. The manner in which these objects of learning are tackled, and the extent to which required conditions are expressed through language during a lesson or crucial in the learning of students (Raban, Brooks, and Wolfendale 1995). It is also worth noting that apart from general conditions such as light, space, some levels of learning activities necessary for learning, the element of language is of much help. Some students may be in a position to learn certain things through symbolic meaning while others may learn through affective guidance and explanation. The place of interaction in learning and the supporting role of the adult Interaction between the child and adult during early learning is of primary importance. Adults act as guidance in almost all activities undertaken by the children (Stone, et al 2004). Adults are supposed to encourage children to act decisively in their undertakings. In this regard, teachers may find it necessary to take advantage of play situations to teach children different concepts. Physical involvement of adults during play attracts children attention as they complement roles adults in the play. Sometimes children may create and assign adults roles, and this is the best opportunity for adults to interact with the children. Some social and emotional aspects of children may not be reflected during normal conversation or in classroom (Stone,
Sunday, October 27, 2019
Mobile Robotic Arm Motivation Computer Science Essay
Mobile Robotic Arm Motivation Computer Science Essay Robotics is technology that deals with the design, construction and operation ofà robotsà that are used in numerous applications is called robotics. It has become an unstoppable force in the development of modern machinery as they make life easier. It is an interesting topic to dwell in as it is the future of mankind. Although we know them as recent inventions, the idea of automated or controlled machines has fascinated humans. With this fascination it motivated me to work on this project, building and programming a mobile robotic arm. It is my hunger to learn and attain knowledge that drives me towards this field of study for my project. C:UsersDanDesktopImages21042010(002).jpg Figure 1.1.1 : Mobile Robotic Arm 1.2 Introduction to Robotics Robotics is an interesting topic of research. Basically it is an engineering field that is concerned with research and creation of robots for various applications. Robots are machines that consist of electronic and mechanical parts such as gears and cogs put together for performing tasks in place of humans. They can be programmed to perform a whole range of tasks with ease. They are most desired for certain functions because they never tire, they can endure harsh physical conditions that is possibly life threatening and they never get bored or distracted from repetitious work. The number of robots has begun to increase in numbers everywhere as they make human labour almost non-existent with their efficiency and throughput. They can work with the simplest of materials to the most dangerous such as radioactive materials. They can be found more commonly in industrial use from production lines of factories to harvesting of fruits in orchards. In domestic use, from vacuum cleaning to lawn mowing where these domestic tasks have become boring for a human to undertake and would rather leave it to robots. In the more modern military use, robots play an important role to reduce human casualties from dangerous jobs such as bomb defusal and not forgetting space exploration where it might not be possible for humans to explore and for collecting terrain sample from foreign planets. For exploring enemy territories unmanned aerial vehicles are used from which these pilotless drones can search terrains for hostiles and fire on targets. Robots are meant to complete tasks that it is programmed to do. Programs can always be altered to suit the task at hand. As robots become more advanced they gain more features such as sensors and artificial intelligence as they become more human like. Examples of sensors include motion sensors, temperature sensors, light and many more various types. For example, in pathfinder robots we usually find a motion sensor which aids a robot in avoiding obstacles. In other applications for example in a water tank when the water has reached a certain level the sensor enables the robot to stop the flow of water. It can be used in industrial applications such as gripping objects from conveyor belts or it can be used in a more advanced role such as bomb defusal, where it would be dangerous for a human to interact. With camera attachments, humans can control these machines from a safe distance while completing the task at hand in a safe and efficient manner. In the medical field where a more delicate touch is required, a robotic arm can perform tiny incisions for a less invasive method. With a robotic arm jobs can be done with ease and efficiency and thus eliminate human errors and the costs that come with those errors. http://www.engr.colostate.edu/~dga/mech324/handouts/linkage_stuff/Mars_rover.png Figure 1.2.1 : Mars Rover 1.3 Objectives The aim of this project is to build a robotic arm for the purpose of lifting and moving small objects. It is just like a human arm with joints to facilitate movement. The end attachment features a gripper which is able to grab and hold objects and also a probe light in order to work in low light scenarios. The arm is controlled via wired remote. It is rested on a mobile base which is fitted with 2 rear wheels and 2 robot castors at the front. This allows the robot to move to the desired location where the object is. The objectives of this project are: To understand and develop core knowledge in robotics. To apply the knowledge of robotics and design a prototype. To implement the designs and build an actual prototype. Figure 1.3.1 : Project Layout End Insert Instruction Codes into PIC Test Prototype Evaluate Coding in relation to hardware design Write Codes Discuss Movement Concept Propose Objectives1.4 Design Stage Figure 1.4.1 : Design Flow Chart This simple flowchart can explain the overall process involved in this project. After the objectives have been proposed the robot movement and motion concept is discussed and after that the codes are written. It is downloaded into the microcontroller for testing. If testing fails we return to the code stage and evaluate the coding. The process reaches the end after testing passes. Chapter 2: Robot Overview 2.1 Hardware Design This aim of this project is to design a mobile robotic arm. The arm part consists of two joints which enable 2 degree of movement and at the end of the top joint is a gripper which enables objects to be gripped by the attachment. The base has two wheels at the back and at the front two robot castors which has ball bearings underneath. This project involves two parts which is hardware and software. However both parts are intricately connected and it is hard to actually separate them completely. This report will focus more on the software aspect. There will be some minor hardware introduction as understanding of the hardware is required to work with the software. Here is the component list for the hardware: Component Amount Microcontroller PIC18F4520 1 Motor Driver SN754410 1 4.7k Ohm Resistor 1 1uF Capacitor 4 0.33uF Capacitor 1 0.1uF Capacitor 1 L7805 Voltage Regulator 1 20MHz Oscillator 1 9 Volt Battery 1 C40R Servo Motor 3 C55R Servo Motor 1 Servo Holder 4 Servo U Bracket 2 SPG10 Geared Motor 2 42mm Wheels 2 Robot Castors 2 Table 2.1.1 : Hardware Components To write the software one must be familiar with the hardware functionality, configuration and settings. The hardware of significant importance would be the microcontroller as the program is stored there. It sends the signal to the pins where other devices are connected. One of those devices is the servo motor. It is what controls the arm and base. Actual control of the servos is by buttons. Those buttons are connected to the microcontroller and is able to control the servo thru programming of the microcontroller. It is done by generating and manipulating PWM signals which will be discussed later. PROJECT BOARD 20.0 cm 24.0 cm 10.0 cm 25.6 cmTOP PROFILE.jpg Figure 2.1.1 : Robot Layout 2.2 Software Design After the purpose and specifications are determined it is time to plan and design the software. Most modern robots are controlled by sophisticated software. Creation and modification of the software is crucial to make machines work the way we want it to. There are many ways a machine can be programmed. The software is usually stored in the heart of the machine which is either a microprocessor or a microcontroller depending on what the machine does and how it works. That device is the brains of the robot as all the instructions are stored there. The software is the link for the user to the hardware as the program relays the instructions to the robot in machine code. The user writes the program in computer language which will then be converted into machine code by the compiler. There are many computer languages available to write programs such assembly, C, Pascal, BASIC and FORTH. For this project the microcontroller that is used is Microchips PIC18F4520. The language used to program the microcontroller is C. C is a simple and procedural language and it has influenced many later languages such Java. It is generally variable and function based. Values are stored in variables for easy access and it is structured by defining and calling functions to perform tasks. C allows precise control of the input and output. The input and output can be easily directed to the microcontroller terminals. The IDE (integrated development environment) that is used for this project is MPLAB which is a 32bit program used for the software development of this project along with the MPLAB C18 compiler add-on to allow the codes to be written in C . This is the screenshot of the development environment: C:UsersDanDesktopFYP ReportimagesUntitled.jpg Figure 2.2.1: MPLAB IDE The general idea of writing the program is to control the pins of the microcontroller. The robot arm mechanism and the base mechanism will be separated for easier explanation. The arm is made up of the 1st stage, 2nd stage, the left gripper and the right gripper. Control of the servos is by generating PWM signals which will be discussed in detail in chapter 4. By manipulation of these PWM signals we can control the servo movement to a certain angle with great precision. For the DC motors in the base, it is controlled via motor controller. By manipulating logic combinations we will be able to control the movement and direction of the base. Infinite loop to check for button press A button is pressed Necessary routine or function is called to move servo/ DC motor End Figure 2.2.2 : General Software Flowchart This is a general flowchart to represent the program flow. A while loop with an infinite condition is used to continuously check if a button has been pressed. If a button is pressed it will call the necessary function to run the specific device whether it is the servo or the DC motor. Chapter 3: Hardware Information 3.1 Microcontroller This project makes use of Microchip Technologys PIC18F4520 microcontroller. Lets discuss in detail what is a microcontroller and how it makes this project work. Notice that a microcontroller is chosen instead of a microprocessor for this project for a number of reasons. To make the choice, one must know the difference between a microcontroller and a microprocessor in terms of functionality and application. Both are typically a small computer in the form of an integrated circuit which contains things like registers, memory, I/O, interrupts and timers. They vary in terms of number of I/O, registers, clock speed and memory size. Microcontrollers are usually for cases that involve a lot of input output devices in contrast to a microprocessor which is usually used for heavy data applications. So that means microcontrollers dominate the robotics and automation industry. Lets examine closely what it looks like and the detailed features for this particular microcontroller, the PIC18F4520. Its versatility, robust nature and features contributed to the choosing of this IC. The detailed features along with its operation can be found in the datasheet for the microcontroller. C:UsersDanDesktopFYP ReportimagesPIC18F4520IP.jpg Figure 3.1.1 : PIC18F4250 Parameter Name à Value à Program Memory Type à Flash à Program Memory (KB) à 32 à CPU Speed (MIPS) à 10 à RAM Bytes à 1,536 à Data EEPROM (bytes) à 256 à Digital Communication Peripherals à 1-A/E/USART, 1-MSSP(SPI/I2C) à Capture/Compare/PWM Peripherals à 1 CCP, 1 ECCP à Timers à 1 x 8-bit, 3 x 16-bit à ADC à 13 ch, 10-bit à Comparators à 2 à Temperature Range (C) à -40 to 125 à Operating Voltage Range (V) à 2 to 5.5 à Pin Count à 40 Table 3.1.1 : PIC18F4250 Specifications Peripheral Highlights: à ¢Ã¢â ¬Ã ¢ High-current sink/source 25 mA/25 mA à ¢Ã¢â ¬Ã ¢ Three programmable external interrupts à ¢Ã¢â ¬Ã ¢ Four input change interrupts à ¢Ã¢â ¬Ã ¢ Up to 2 Capture/Compare/PWM (CCP) modules, one with Auto-Shutdown (28-pin devices) à ¢Ã¢â ¬Ã ¢ Enhanced Capture/Compare/PWM (ECCP) module (40/44-pin devices only): One, two or four PWM outputs Selectable polarity Programmable dead time Auto-Shutdown and Auto-Restart à ¢Ã¢â ¬Ã ¢ Master Synchronous Serial Port (MSSP) module supporting 3-wire SPIà ¢Ã¢â¬Å¾Ã ¢ (all 4 modes) and I2Cà ¢Ã¢â¬Å¾Ã ¢ Master and Slave Modes à ¢Ã¢â ¬Ã ¢ Enhanced Addressable USART module: Supports RS-485, RS-232 and LIN 1.2 RS-232 operation using internal oscillator block (no external crystal required) Auto-Wake-up on Start bit Auto-Baud Detect à ¢Ã¢â ¬Ã ¢ 10-bit, up to 13-channel Analog-to-Digital Converter module (A/D): Auto-acquisition capability Conversion available during Sleep à ¢Ã¢â ¬Ã ¢ Dual analog comparators with input multiplexing) Power Managed Modes: à ¢Ã¢â ¬Ã ¢ Run: CPU on, peripherals on à ¢Ã¢â ¬Ã ¢ Idle: CPU off, peripherals on à ¢Ã¢â ¬Ã ¢ Sleep: CPU off, peripherals off à ¢Ã¢â ¬Ã ¢ Idle mode currents down to 5.8 ÃŽà ¼A typical à ¢Ã¢â ¬Ã ¢ Sleep mode current down to 0.1 ÃŽà ¼A typical à ¢Ã¢â ¬Ã ¢ Timer1 Oscillator: 1.8 ÃŽà ¼A, 32 kHz, 2V à ¢Ã¢â ¬Ã ¢ Watchdog Timer: 2.1 ÃŽà ¼A à ¢Ã¢â ¬Ã ¢ Two-Speed Oscillator Start-up Flexible Oscillator Structure: à ¢Ã¢â ¬Ã ¢ Four Crystal modes, up to 40 MHz à ¢Ã¢â ¬Ã ¢ 4X Phase Lock Loop (available for crystal and internal oscillators) à ¢Ã¢â ¬Ã ¢ Two External RC modes, up to 4 MHz à ¢Ã¢â ¬Ã ¢ Two External Clock modes, up to 40 MHz à ¢Ã¢â ¬Ã ¢ Internal oscillator block: 8 user selectable frequencies, from 31 kHz to 8 MHz Provides a complete range of clock speeds from 31 kHz to 32 MHz when used with PLL User tuneable to compensate for frequency drift à ¢Ã¢â ¬Ã ¢ Secondary oscillator using Timer1 @ 32 kHz à ¢Ã¢â ¬Ã ¢ Fail-Safe Clock Monitor: Allows for safe shutdown if peripheral clock stops Special Microcontroller Features: à ¢Ã¢â ¬Ã ¢ C compiler optimized architecture: Optional extended instruction set designed to optimize re-entrant code à ¢Ã¢â ¬Ã ¢ 100,000 erase/write cycle Enhanced Flash program memory typical à ¢Ã¢â ¬Ã ¢ 1,000,000 erase/write cycle Data EEPROM memory typical à ¢Ã¢â ¬Ã ¢ Flash/Data EEPROM Retention: 100 years typical à ¢Ã¢â ¬Ã ¢ Self-programmable under software control à ¢Ã¢â ¬Ã ¢ Priority levels for interrupts à ¢Ã¢â ¬Ã ¢ 8 x 8 Single-Cycle Hardware Multiplier à ¢Ã¢â ¬Ã ¢ Extended Watchdog Timer (WDT): Programmable period from 4 ms to 131s à ¢Ã¢â ¬Ã ¢ Single-supply 5V In-Circuit Serial Programmingà ¢Ã¢â¬Å¾Ã ¢ (ICSPà ¢Ã¢â¬Å¾Ã ¢) via two pins à ¢Ã¢â ¬Ã ¢ In-Circuit Debug (ICD) via two pins à ¢Ã¢â ¬Ã ¢ Wide operating voltage range: 2.0V to 5.5V à ¢Ã¢â ¬Ã ¢ Programmable 16-level High/Low-Voltage Detection (HLVD) module: Supports interrupt on High/Low-Voltage Detection à ¢Ã¢â ¬Ã ¢ Programmable Brown-out Reset (BOR With software enable option Here is a list of pins and how they are connected in the circuit. Pin Name Pin Number (PDIP) Functions MCLR 1 Reset RA1 3 Servo PWM Input RA2 4 Servo PWM Input RA3 5 Servo PWM Input RA4 6 Servo PWM Input VDD 11 +5V VSS 12 Grounded OSC1 13 Oscillator Crystal/External Clock Input OSC2 14 Oscillator Crystal/External Clock Input RC0 15 IN2 of Motor Driver RC1 16 IN1 of Motor Driver RC3 18 IN4 of Motor Driver RD0 19 IN3 of Motor Driver VSS 31 Grounded VDD 32 +5V RB0 33 Motor Push Button RB1 34 Motor Push Button RB2 35 Motor Push Button RB3 36 Motor Push Button RB4 37 Servo Arm Push Button RB5 38 Servo Arm Push Button RB6 39 Servo Arm Push Button RB7 40 Servo Arm Push Button Table 3.1.2 : Pin Connections C:UsersDanialDesktopFull Schem.JPG Figure 3.1.2 : Full Schematics 3.2 Motor Driver Figure 3.2.1 : SN754410 Motor Driver The SN754410NE is a quadruple half-H driver. The SN754410 can operate a pair of DC motors at the same time. It gives the robot bidirectional movements. It carries the peak output currents up to 1 ampere at a voltage range of 4.5 to 36V. The SN754410 has a minimum logic voltage of 4.5V and a maximum logic voltage of 5.5V. This driver is made to operate from a -400C to 850C. Drivers are enabled in pairs. Driver 1 and driver 2 are enabled by 1,2EN. Driver 3 and driver 4 are enabled by 3,4EN. When the input is low, the drivers are disabled and the outputs are off. If the input is high, the drivers are enabled and the outputs are on. Figure 3.2.2 : SN754410 Motor Driver Pinout Pin 1 (1,2EN) enables/ disables the motor Pin 2 (1A) is a logic pin for the motor Pin 3 (1Y) is for Motor A Pin 4, 5 are for grounding Pin 6 (2Y) is for Motor A Pin 7 (2A) connected to the motor Pin 8 (VCC2) connected to source for motor power Pin 9 (3,4EN) enables/ disables the motor Pin 10 (3A) connected to the motor Pin 11 (3Y) is for Motor B Pin 12, 13 are for grounding Pin 14 (4Y) is for Motor B Pin 15 (4A) connected to the motor INPUTS OUTPUT Y H = High Level L = Low Level X = Do Not Matter XX = OFF A EN H H H L H L X L XX Table 3.2.1 : SN754410 Function Table C:UsersDanialDesktopMotor.JPG Figure 3.2.3 : Motor Schematics 3.3 DC Motor This project will use the SPG10 Geared Motor that has 1.3 kg/cm torque. This motor is light enough to not weigh down the robot and only weighs 10 grams. It runs at 45 rpm. Figure 3.3.1 : SPG10 Motor C:UsersDanDesktopImages23042010(001).jpg Figure 3.3.2 : Motor Wheel 3.4 Servo Motor A servo is a mechanism used in robotic control systems. It is a mechanism that the user can set and forget. This is because of its ability to make corrections to return to its preset state if any changes occur. This is thanks to feedback operations. A servo is a casing that contains a DC motor, some gears with an output shaft, a variable resister that is connected to the output shaft, and a control board. The sensor mechanism allows the control circuit to monitor the current. The motor, through a series of gears, turns the output. The control circuit calculates the difference from the intended position from the current position the shaft is in. This makes the motor turn to its new position. If the control circuit senses that the position is accurate, it brings to a halt the motor. There are three connections to a servo; the power line, the ground line and finally the control signal. The servo needs to be told when to move and wont do so even if power is provided directly. The servo utilizes pulse width modulation (PWM) stream to indicate its position. Specification Servo Motor Model At 5 Volts Speed (s/60o) 0.19 Torque (Kg.cm) 6.00 Signal To Control Angle TTL PWM PWM At Min Angle (ms) 0.54 PWM At Max Angle (ms) 2.40 Operating Voltage (VDC) 4.8-6.0 Operating Frequency (Hz) 50.0 Moving Range(degree) 0-180 Wiring (Black/Brown Wire) Ground Wiring (Red Wire) 4.8-6.0 Volts Wiring (Orange/Other Wire) PWM Signal Table 3.4.1 : Servo Specifications C:UsersDanialDesktopUntitled.jpg Figure 3.4.1 : Servo Motor C:UsersDanialDesktopServo.JPG Figure 3.4.2 : Servo Schematic Chapter 4: Software Coding 4.1 PWM Generation PWM is simply the short form for pulse-width modulation. It is an efficient way to provide intermediate amounts of electrical power between fully on and fully off. This means PWM signals are digital, because at any instant given instant of time, the full DC supply is either fully on or fully off. PWM is employed in a wide variety of applications, ranging from measurement and communications to power control and conversion. Many microcontrollers include on-chip PWM controllers, like the one which is used this project, which makes this easy for controlling the servos for this project. One of the advantages of PWM is that the signal remains digital all the way from the processor to the controlled system and no digital-to-analog conversion is necessary. By keeping the signal digital, noise effects are minimized. Noise can only affect a digital signal if it is strong enough to change logic 1 to logic 0, or vice versa. PWM is the basis of controlling the servos in this project. Lets examine some basic theory. C:UsersDanDesktopFYP Reportimagespwm.gif Figure 4.1.1 : PWM Square Wave The diagram above shows a PWM signal that changes between 0 and 5 volts which is equivalent as digital logic 0 and 1. Notice that the waves are symmetrical. The uptime and downtime is 10ms when added together we get the period which is 20ms. Now that the basics are out of the way, lets look at how a normal servo signal input looks like. C:UsersDanDesktopFYP Reportimagespwm_servo.gif Figure 4.1.2 : PWM Wave Note that the servo runs at 50Hz frequency and therefore the period is 20ms. The uptime is what determines the angle of which the servo motor moves to. In simple words, we can tell the servo where to move with great precision. These are some examples for 180à ° servos. t = 0.9ms T = 20ms Angle = 0à ° t = 1.5ms T = 20ms Angle = 90à ° t = 2.1ms T = 20ms Angle = 180à ° The next step is to create these PWM signals using the PIC microcontroller. The PWMs is in this switch statement: switch(count){ //Choose which servo to modify case 1: PORTA = 0x02; // First Stage WriteTimer1( servo3 ); break; case 2: PORTA = 0x04; // Left Gripper WriteTimer1( servo1 ); break; case 3: PORTA = 0x08; //Right Gripper WriteTimer1( servo0 ); break; case 4: PORTA = 0x10; // Second Stage WriteTimer1( servo2 ); break; } Figure 4.1.3 : Switch Statement The operations for the timers are split in to 4 possible cases of how to generate PWM signal to the pins to power the servos. This is what the statement does: à à à à à à à à à à //INTERRUPT CONTROL #pragma code InterruptVectorHigh=0x08 void InterruptVectorHigh (void) { _asmà à à à à à //assembly code starts goto InterruptHandlerHigh à à à à à à à à à à //interrupt control _endasmà à à //assembly code ends } #pragma code #pragma interrupt InterruptHandlerHigh à à à à à à à à à à //end interrupt controlCase 1 turns PortA1 On and resets the timer1.à Case 2 turns PortA1 Off, PortA2 on and resets the timer1. Case 3 turns PortA2 Off, PortA3 on and resets the timer1. Case 4 turns PortA3 Off, PortA4 on and resets the timer1. Figure 4.1.4 : Interrupt Handler The switch statement is nested in the interrupt handler function. The interrupt handler handles the timer operations. The interrupt control runs assembly code and then calls the go-to function which is InterruptHandlerHigh. The interrupt controller is set at high priority 0x08. Once the interrupt control is correctly implemented interrupts is sent to the interrupt handler where we can do whatever operation necessary depending on the type of interrupt.à 4.2 Arm Control void move(int one,int two,int three,int four, int five) { if(one) servo0 = one; // Right Gripper if(two) servo1 = two; // Left Gripper if(three) servo2 = three; // Second Stage Link if(four) servo3 = four; // First Stage Link }A move function is declared to make things easier when linking with buttons. The arguments of the move function are the respective position the servo moves to when it is called upon. Figure 4.2.1 : Move Function After the move function is declared it can be called when the specific button is pressed. //Arm Control if(PORTBbits.RB7==1) move(0xF03B,0xF477,0,0,0); //GRIP! if(PORTBbits.RB6==1) move(0,0,(servo2-0x0250),(servo3+0x0100),0); //MOVE AWAY if(PORTBbits.RB5==1) move(0,0,(servo2+0x0250),(servo3-0x0100),0); //MOVE TOWARDS if(PORTBbits.RB4==1) move(0xFA77,0xEE07,0,0,0); //UNGRIP! Figure 4.2.2 : Arm Button Check There are 4 buttons that control the movement of the arm. PortB pin 0: Close the gripper PortB pin 1: Move arm away PortB pin 2: Move arm towards PortB pin 3: Open the gripper C:UsersVictorDesktopImagesClose Gripper.jpg Figure 4.2.3 : Close Gripper This picture depicts a closed gripper state that is triggered by the button. The following figure is how the robotic arm will look when it is triggered to open both grippers. C:UsersDanDesktop22042010(007).jpg Figure 4.2.3 : Open Gripper 4.3 Base Control The only thing that needs to be controlled in the base is the 2 DC geared motors. It is linked with the microcontroller through the H-bridge. The motors rotational direction is determined by a combinational logic code as seen in the data sheet of the motor driver. It is the same with the servo, when a button is pressed certain commands will be executed. //Base Control if(PORTBbits.RB3==1) { //Forward control PORTCbits.RC1=1; PORTCbits.RC0=0; PORTDbits.RD0=1; PORTCbits.RC3=0; } if(PORTBbits.RB2==1) { //Reverse control PORTCbits.RC1=0; PORTCbits.RC0=1; PORTDbits.RD0=0; PORTCbits.RC3=1; } Figure 4.3.1 : Base Button Check (Forward/Reverse) if(PORTBbits.RB1==1) { //Left control PORTCbits.RC1=0; PORTCbits.RC0=1; PORTDbits.RD0=1; PORTCbits.RC3=0; } if(PORTBbits.RB0) { //Right Control PORTCbits.RC1=1; PORTCbits.RC0=0; PORTDbits.RD0=0; PORTCbits.RC3=1; } Figure 4.3.2 : Base Button Check (Left/Right) There are 4 buttons that control the movement of the base. PortB pin 4: Forward PortB pin 5: Reverse PortB pin 6: Move right PortB pin 7: Move left 4.4 Simulation C:UsersDanDesktopUntitled.jpg Figure 4.4.1 : Watch Simulation The MPLAB software allows a minimal amount of simulation to show that the program is written correctly. Due to software limitation on the PIC18F4520 it is unable to correctly show port activities. However it does show variable activity like in the figure by using the watch feature in the MPLAB. This screenshot shows the stepping when reaching the OpenTimer1 function. A separate window opens to show the function and it will continue to step through the function until it is done. C:UsersDanDesktopUntitled1.jpg Figure 4.4.2 : Program Stepping The stepping continues while opening the necessary functions in a separate window and steps though it until it is done. It reaches the while loop and it keeps looping as it waits for a button to be pressed. Figure 4.4.3 shows the final stage of the program stepping. C:UsersDanDesktopUntitled3.jpg Figure 4.4.3 : Final Stepping Chapter 5: Conclusions and Recommendation 5.1 Summary This project has further expanded my interest and knowledge in the field of robotics. A project that is very hands on like this helps with the development of certain skills that would certainly help when I go on to become a professional engineer. The most important skill would be planning the stages of the project. To conclude, this project involved two phases which is the hardware design and software design. This report covered the software aspect in detail. In the early stages of this project different methods was planned for the outcome. At the start, the use of a PLC (programmable logic controller) was planned. However it proved to be infeasible in terms of cost and size. In the end it was decided that a PIC microcontroller was to be use as it is easier to implement with respect to the project and provides a great deal of functionality. The programming was made easier with the addition of the C compiler thus enabling the use of a higher level language which is C. With the use of a language of higher level it would be easier to implement features that were not possible using the PLC. 5.2 Recommendations In this project, certain improvements can be made in order to make things work more efficiently. For example, the quick movements seen in the arm is because of the incrementer seen in the codes and lack true control software. By revising the software and introducing more control oriented design it is possible to fine tune the speed. Instead of the 2 robot castors that make up the front motion it could be replaced with wheels and a servo in between them to make the movement and control similar to remote controlled cars. The wired controller could be replaced with a wireless RF controller to allow more freedom to the user. The body work could be improved by using sturdier and lightweight materials such as aluminium. Some sensors could be added to enhance the normal usage of the arm.
Friday, October 25, 2019
Climate Change: Global Emissions of Green House Gases Essay -- Environ
There are growing concerns about climate change and the effect of ââ¬Ëgreenhouse gasesââ¬â¢ (GHG) on the gradual increase in world temperatures over time, now commonly known as global warming. The ââ¬Ëgreenhouse effectââ¬â¢ means that ââ¬Ëgreenhouse gasesââ¬â¢ such as water vapour (H2O), carbon dioxide (CO2), methane, nitrous oxide, and fluorocarbons insulate the Earth by absorbing heat from the Earthââ¬â¢s surface and reflecting it back into the atmosphere, acting in a similar way to a thermal blanket (Houghton, 2005). Although associated in recent times with pollution and climate change, the ââ¬Ëgreenhouse effectââ¬â¢ is essential for the continuity of the Earthââ¬â¢s climate (Karl and Trenberth, 2003). However, since the beginning of the Industrial Revolution (from the 18th to the 19th Century), the burning of fossil fuel meant that the greenhouse effect went from simply protecting the Earthââ¬â¢s climate to causing an actual increase in world temperatures (Martinez, 2005; Houghton, 2005). The gaseous culprit is the seemingly innocuous CO2, although harmless in the right atmospheric proportions, it is nevertheless a very powerful insulator and heat reflector (Houghton, 2005). Since 1750, the concentration of CO2 has increased by over 30% and is now at a higher level than it has been for thousands of years (Martinez, 2005; EPA, 2007). In fact, it is argued that if no action is taken to curb these emissions, then the concentration of CO2 will rise throughout the remainder of this century to two or three times its preindustrial level (Houghton, 2005). The Scientific evidence on global warming dates as far back as the second half of the 19th Century and the work of physicist John Tyndall and chemist Svente Arrhenius. It was particularly accelerated in the past 20... ...add around 7 meters to the worldââ¬â¢s sea level (Gregory et al., 2004), with extremely damaging results for mankind and the ecosystem (Houghton, 2005). Global emissions of CO2 to the atmosphere from fossil fuel burning are approaching 7 billion tonnes of CO2 per annum and are rising rapidly (Houghton, 2005; Stern, 2006). In fact, energy related emissions are forecasted to grow by over 2% per year over the next 30 years, if the world community continue with ââ¬Ëbusiness as usualââ¬â¢ (Stern, 2006). However, emissions during the 21st century must be reduced to a fraction of their present levels before the centuryââ¬â¢s end in order to stabilize CO2 concentrations (Houghton, 2005; Stern, 2006). Effective responses require collective action (Stern, 2006) and global efforts are needed to develop global solutions to overcome these global problems (Houghton, 2005, Stern, 2006).
Thursday, October 24, 2019
Crackling Day By Peter Abrahams Essay
ââ¬Å"Crackling dayââ¬â¢ is a story about a young black boy in South Africa that challenges three white youths and, in so doing, challenges the political system of the whole country. The very famous writer Peter Abrahams wrote it. It set in Africa in the times of apartheid. Apartheid was a ââ¬Å"systemââ¬â¢ or a mentality as it were was apposed on South Africa after the Second World War and the country gained independence from Great Britain. This did not mean that it would be the South Africans that ââ¬Å"ranââ¬â¢ the country, as it was the British that were still in control. Apartheid laws were imposed on South Africa in 1948 and on June 13, 1950 the Group Areas Act was enacted. It segregated communities and relegated the black population to a minor percentage of the nationââ¬â¢s land, therefore meaning that white people mostly owned the land and the land on which the black people resided was often not even theirs. Everyone in the country had to register themselves as white, black (African), or coloured (of mixed race e.g. Asian). In 1953, the Public Safety Act and the Criminal Law Amendment Act were passed, which empowered the government to declare stringent states of emergency and increased penalties for protesting against or supporting the repeal of a law. The penalties included fines, imprisonment and whippings. In 1960, a large group of blacks in Sharpsville refused to carry their passes; the government declared a state of emergency. The emergency lasted for 156 days, leaving 69 people dead and 187 people wounded. Wielding the Public Safety Act and the Criminal Law Amendment Act, the white regime had no intention of changing the unjust laws of apartheid. In 1989 there were approximately 19 million blacks in the country and on 4.5 million whites and yet whites had 87% of the land and blacks owned only 13%. The whites also received about 75% of the countries income with the blacks receiving 25% or less. The health and education services that blacks were allowed was also appalling with one doctor per 44,000 blacks whereas the whites had one doctor per 400 people and 1 teacher per 60 blacks whereas there was 1 teacher per 22 whites. Apartheid and how it affected people is the main subject of the story and canà clearly be seen throughout. Lee had to collect cow dung everyday so that he, his Aunt and his Uncle could use it as fuel. It was the only material that they could use for cooking and as a fire, possibly the only thing that they could use to keep their ââ¬Å"houseââ¬â¢ warm. Lee and all ââ¬Å"the children of the location made the long trek to Elsberg siding for the square of pigââ¬â¢s rind that passed for out daily meatââ¬â¢. The children had to do this once a week, every Wednesday. Also not the place where the lived was simply ââ¬Å"the locationââ¬â¢ and had no name, whereas the place they were heading towards (where all the white people lived) did have a name, Elsberg. This gives the reader the thought that where the black people lived was considered a place that didnââ¬â¢t matter hence it had no name. Elsberg was also not a close by town; it was a ââ¬Å"long trekââ¬â¢. This meant that the white people lived far away from the blacks, coincidence or purposefully put so that they were split up from each other? From the evidence and the time in which the story is set I would have to say that this was no coincidence. In the time of Apartheid the different ââ¬Å"race groupsââ¬â¢ were split up and it is therefore my conclusion that the whites did not want to live near the blacks, whereas the blacks had no choice. What we also notice that is a very important fact is that they cannot have any ââ¬Å"daily meatââ¬â¢ and are instead walking miles for some pig crackling. This is not a nutritious thing to eat but they either couldnââ¬â¢t afford to buy meat or are not allowed any by the ââ¬Å"baasââ¬â¢. The crackling that they do get is not even given to them. Earlier in the story we read that Leeââ¬â¢s Aunt wore a ââ¬Å"thinââ¬â¢ (she, therefore is thin) dress with a pocket that was ââ¬Å"nearest the skinââ¬â¢ and that ââ¬Å"from this she pulled a sixpenny pieceââ¬â¢ and ââ¬Å"tied it in a knot on the corner on the corner of a bit of coloured clothââ¬â¢. With this sixpenny (worth about 2.5 pence in todayââ¬â¢s money) he bought the crackling off of the white man. Also note that it says that Lee ââ¬Å"tucked it into the little canvas bagââ¬â¢. The word little is quite emotive as it shows that Lee does not have much. The man that was serving the crackling to the black children ââ¬Å"did it in leisurely fashion, with long pauses for a smokeââ¬â¢ and he ââ¬Å"occasionally turned his backââ¬â¢. From this we can see the affects of apartheid and what it does toà people. The ââ¬Å"young manââ¬â¢ that was serving them was taking his time, and being facetious, flippant and dismissive. Not only that, but he was doing this towards young children. We can see that apartheid has made this young man think that he is greater than black children. This, therefore in his mind has justified his actions in believing he had the right to behave in such a manner. Apartheid, being part of South Africaââ¬â¢s legislation did give him the right to act in this manner by law. Along with apartheid in ââ¬Å"Crackling Dayââ¬â¢, there are also tough living conditions evident. Lee lives with his Uncle and Aunt but it is the white manââ¬â¢s land that they are living on. We can see this when later in the story the white man wants Uncle Sam to ââ¬Å"teach himââ¬â¢ and warns Sam ââ¬Å"if you and he are to live here, you must teach himââ¬â¢. From this we can see that the white man wants Lee to be ââ¬Å"taught a lessonââ¬â¢ but does not want to have to punish him himself. It would be much more upsetting for Sam, Liza and Lee if Sam himself did it. Note that he does not include Aunt Liza when he is talking about the people living on his land. This is because in the times of apartheid it wasnââ¬â¢t just racism that was infection, it was sexism as well. Aunt Liza, being a woman, was not considered much and not worth much. This plays a crucial part later on in that particular scene. Lee also had to walk out in the cold with bare feet and they therefore cannot afford or obtain shoes. The author also uses different language styles to emphasize just how tough it is. He uses hyperbole like when he said ââ¬Å"after what seemed hoursââ¬â¢. He uses personification of the cold so that it makes us picture in our minds just how bad it is and how much of a ââ¬Å"cruel enemyââ¬â¢ it was. He uses similes like when he said that the morning air ââ¬Å"went down my throat like an icy draughtââ¬â¢. He uses alliteration like when he said that the ââ¬Å"sun sat high in the skyââ¬â¢. Note he also used alliteration and personification and alliteration in that last sentence saying that the sun ââ¬Å"satââ¬â¢. To always have to be humble, differential and submissive in the presence of someone who is so arrogant, aggressive and forceful cannot be easy. They also have to deal with collecting cow dung for fuel, eating only crackling and bread for which they have to walk for hours for, always having to ââ¬Å"turn the other cheekââ¬â¢ and deal with all the rest of the immoral acts injustices that they are regularly put through. As a result of these facts, all the characters feel fear and need to show courage on a daily basis. Some examples of the difficult conditions which individual characters face are like when Lee and Andreas were startled by a ââ¬Å"Boer dogââ¬â¢ (Boer being the term that described the settlers that came from Europe and Settled in South Africa). These dogs were trained to kill black people and this is something that young children had to face. The two had to get away from the dog (even though it was behind a fence). Uncle Sam has to live in fear of the white man because, by law, he is their superior and the fact that they are living on his land means that he could throw them out into the realms of homelessness where the destitute struggle. However, there are also specific incidents, which reveal the themes of courage and fear. The most prolific, courageous and important incident was one that seemed almost hidden. After Uncle Sam had beaten Lee the white man and the boys were leaving. The white man said ââ¬Å"Good Nightââ¬â¢ to Sam, to which Sam replied ââ¬Å"Good night baas, sorry about all thisââ¬â¢. The white man then said ââ¬Å"Good night, Lizaââ¬â¢ and ââ¬Å"Liza did not answerââ¬â¢. This is very significant, as not replying to the white man could be shown as disrespectful and even breaking the law. The family could have been thrown off of the land for it. But, as stated earlier Aunt Liza is a woman and as such was considered not worth it by the white man. Just Before this Aunt Liza had also shown courage. After Sam had beaten Lee the white man said ââ¬Å"bet his fatherââ¬â¢s one of those who believe in equalityââ¬â¢. Aunt Liza said very bluntly to this ââ¬Å"his father is deadââ¬â¢. This was not a humble thing to say, which was what was expected of her being black and a woman. Lee showed courage on two occasions. The first was when he and Andreas were running away from the white boys who were shouting at them ââ¬Å"your fathers are dirty black bastards of baboons!ââ¬â¢ Lee showed courage by stopping, turning round and ââ¬Å"screamingââ¬â¢ ââ¬Å"Youââ¬â¢re a Liar!ââ¬â¢ What prepared us for this was the fact that when Andreas was telling Lee that they should run and then changed his mind and told him to walk quietly Lee kept on asking ââ¬Å"why?ââ¬â¢ Lee wasnââ¬â¢t as ââ¬Å"street-wiseââ¬â¢ as it were when it came to avoiding the white children and how to act around white people. This is probably due to Lee being an ââ¬Å"out-of-townerââ¬â¢ and he had just come from Johannesburg. This was courageous in the sense that not only was he standing up to the white boys but also he was standing up to the whole political system of the country. The second time that Lee showed courage was when Uncle Sam told Lee to tell the white man that he is sorry. This he did not and instead pleaded ââ¬Å"he insulted my fatherââ¬â¢. This is a lot of courage to show for a small boy, and I donââ¬â¢t think it was out of stubbornness. In ââ¬Å"Crackling Dayââ¬â¢ Lee faces many challenges: he feels fear and displays courage in dealing with his fears. One example of this is the cold whether. Lee has to go out every Wednesday and walk for hours in the cold. He first shows courage out of dealing with this instead of winging about it, he even ââ¬Å"trotted offââ¬â¢ as if he was willing to go. This shows he has a positive attitude towards this, which in itself requires tremendous courage. The author talks about the cold a lot during the story. He also utilizes different language styles to do so. He started by using similes about how cold the morning air was: ââ¬Å"There was a sharp bite to the morning air I sucked in; it stung my nose so that tears came to my eyes; it went down my throat like an icy draught; my nose ranââ¬â¢. That was a long sentence! He uses this repetition for the sake of emphasis and effect. He also used a simile in there when it said ââ¬Å"it went down my throat like an icy draughtââ¬â¢. This is to give the reader the right picture and feeling of what itââ¬â¢s like and how hard it is for Lee. So in one sentenceà he put in repetition and a simile. The story continues: ââ¬Å"I tried breathing through my mouth, but this was worse. The cold went through my shirt and shorts; my skin went pimply and chilled; my fingers went numb and began to ache; my feet felt like frozen lumps that did not belong to me, yet jarred and hurt each time I put them down. I began to feel sick and desperateââ¬â¢. The second sentence again had repetition and a simile. So from that paragraph there is a long sentence, a short one, a long one, and again a short one. All this adds up to allow some insight as to what it was like for him. We can see how immoral it is for this young boy to have to go through all the suffering, not once, but every Wednesday. It then says later on: ââ¬Å"We were creatures haunted and hounded by the cold.ââ¬â¢ Thereââ¬â¢s a metaphor. ââ¬Å"It was a cruel enemy who gave no quarterââ¬â¢. Thatââ¬â¢s very emotive personification. ââ¬Å"And our meanings of fighting it were pitifully inadequate. In all the mornings and evenings of the winter months, young and old, big and small, were helpless victims of the bitter cold.ââ¬â¢ Now the writer has started referring to the cold as ââ¬Å"itââ¬â¢ and ââ¬Å"bitterââ¬â¢. The story continues: ââ¬Å"Only toward noon and in the early afternoon, when the sun sat high in the sky, was there a brief respite.ââ¬â¢ There we have two instances of alliteration. ââ¬Å"For us, the children, the cold, especially the morning cold, assumed an awful a malevolent personality.ââ¬â¢ A lot of personification there, even describing ââ¬Å"itsââ¬â¢ personality! ââ¬Å"We talked of ââ¬Å"itââ¬â¢. ââ¬Å"Itââ¬â¢ was a half-human monster with evil thoughts, evil intentions, bent on destroying us.ââ¬â¢ Much more personification that helps us see how much of an ââ¬Å"enemyââ¬â¢ the cold was. The author has just ââ¬Å"painted us a pictureââ¬â¢ of what it was like for these two boys and how the hated and feared the cold. All of this tells us that Lee and Andreas are two boys that accept the way that they have to live and face it with courage and with a positive attitude. They realise that that is the society that they have to live inà and accept their lives. Another thing that Lee and Andreas fear is Hunger. The author shows this by, again, using personification and use of language. We are told ââ¬Å"Hunger was an enemy too, but one with whom we could come terms, who had many values and virtuesââ¬â¢. We are told here how hunger was also an enemy but not as bad as the cold. The author uses personification of these two factors (the cold and the hunger) is very skilfully. The incident with the man giving out the crackling demonstrates the theme of power and itââ¬â¢s importance in society. As stated earlier the man that was serving the crackling to the black children ââ¬Å"did it in leisurely fashion, with long pauses for a smokeââ¬â¢ and he ââ¬Å"occasionally turned his backââ¬â¢. Lee, Andreas and the rest of the black children have to call the white man ââ¬Å"baasââ¬â¢ as a sign of respect. The white man wouldnââ¬â¢t serve Lee until he did: â⬠ââ¬Å"well?â⬠the man repeated coldly. ââ¬Å"Please, baas,ââ¬â¢ I said. ââ¬Å"What dââ¬â¢you want?â⬠ââ¬Å"Sixpence crackling, please.â⬠ââ¬Å"What?â⬠Andreas dug me in the ribs. ââ¬Å"Sixpence crackling, please.â⬠ââ¬Å"What?â⬠ââ¬Å"Sixpence crackling, please, baasâ⬠ââ¬Ë. We can see that the white man has far more power than Lee or Andreas and as such they have to treat him as their superior. To respond in the way that Lee and Aunt Liza did to their fear demands courage because by law they are in the wrong. When Lee stands up to the white boys and when Aunt Liza stands up to the white man they are also standing up to the entire political system of their culture at that time. For doing so they could be beaten, thrown off of the white manââ¬â¢s land or even killed. The author is showing the difference in position between whites and blacks. He does this by showing that the man selling the crackling and the white man that owns the land can do whatever pleases them and get the black people to do whatever pleases them. The black people have to respond by being humble, differential and submissive. The character of Uncle Sam is what would be expected of him in that culture and time period. When he came home and Aunt Liza told him what had happened the author says ââ¬Å"he, too, just looked at me and became more remote and withdrawn. They were waiting for something.ââ¬â¢ Uncle Sam and Aunt Liza knew that that got beaten up by Lee would probably either tell his parents or his parents would see the bruises and ask what had happened. They knew that the white man would be coming round to their house to enquire what had happened. Uncle Sam was probably in a state of fear, of the white man, hence him becoming ââ¬Å"remoteââ¬â¢ and ââ¬Å"withdrawnââ¬â¢. Another thing that displays that he is in a state of fear is that when they heard ââ¬Å"a trap pull up outsideââ¬â¢ Uncle Sam simply says ââ¬Å"here it comes.ââ¬â¢ When people are anxious, worried or afraid they tend to murmur or talk quickly. When the door ââ¬Å"burst openââ¬â¢ and the ââ¬Å"tall, broad white man strode inââ¬â¢ Uncle Sam greeted him in a respectful, humble manner (what was expected of him) by saying ââ¬Å"Evening, baasââ¬â¢ and the text then tells us ââ¬Å"Uncle Sam murmuredââ¬â¢. It even tells us that he is murmuring! It then later says â⬠ââ¬Å"Heââ¬â¢s sorry, baas,â⬠Uncle Sam said quicklyââ¬â¢. This definitely tells us that he is afraid of something as he is talking ââ¬Å"quicklyââ¬â¢. Uncle Sam does show courage when he lies to the white man. He tells him ââ¬Å"Iââ¬â¢ve given him a hiding he wonââ¬â¢t forgetââ¬â¢. The white man could easily find out, by examining Lee and this, again, could get the family thrown off of the white manââ¬â¢s land. When Lee doesnââ¬â¢t tell the white man that he is sorry and instead says that they ââ¬Å"insultedââ¬â¢ his father the white man makes Uncle Sam beat Lee. As he is doing so he says ââ¬Å"You must never lift your hand to a white personââ¬â¢ and it describes him as saying so ââ¬Å"bitterlyââ¬â¢. He is saying it ââ¬Å"bitterlyââ¬â¢ because of course he doesnââ¬â¢t want to have to hurt Lee. Sam beats Lee because he knows that he has to. If he doesnââ¬â¢t then all manner of things could happen to him,à Liza and Lee, the least of which being thrown off of the white manââ¬â¢s land. After they have left Sam begins to sob. This is because he feels so guilty and angry with himself, the white man, and the political system that they have to live under. The next day he simply says to Aunt Liza ââ¬Å"One dayâ⬠à ¦Ã¢â¬â¢ This is a threat towards the white man and, again the political system. It is probably an empty and hollow threat but he has to keep thinking this to give him a reason to be angry and something to be angry at. The next day Liza was ââ¬Å"dishing out the foodââ¬â¢ to Sam and Lee and ââ¬Å"insistentlyââ¬â¢ reassured Sam ââ¬Å"Itââ¬â¢s all rightââ¬â¢. Liza understood that Sam did what he had to do and that Sam was feeling guilty. She knew that he needed some comfort and assurance that what he did was what he had to. In conclusion, the types of courage and fears demonstrated in ââ¬Å"Crackling Dayââ¬â¢ are facing up to reality, doing what you have to do, though it may not be right, standing up to what you feel is wrong. All the main black characters through the story show some type of fear one-way of another. Uncle Sam was afraid of the results if he did not do what the white man told him but he still did not want to hurt Lee. Samââ¬â¢s courage was lying to the white man in a desperate attempt to prevent Lee from being hurt or being completely exposed to the injustice and immorality of apartheid. Aunt Liza showed incredible courage when she did not reply to the white man even though she knew that it might cause the family to suffer. Lee and Andreas both showed fear by actually going out and facing the cold, hunger and the long hours of walking. Lee single-handedly showed courage when he stood up to the white boys and when he did not say he was sorry (the first time anyway) to the white man. The message the author is trying to communicate in ââ¬Å"Crackling Dayââ¬â¢ is that fear and a hard way of life bring courage and even the most unlikely people can be the most courageous. I think the main point that the author was trying to put to the reader is the immorality of apartheid and racism and what it can do to people physically and mentally.
Wednesday, October 23, 2019
Public Policy Making in Zimbabwe
For the past ten years, Zimbabwe has been riddled with economic stagnation as well as being the subject of political instability, thus that been the reasonà why many companies and countries have turned a blind eye as concerns investing. Once known as the bread basket of Africa, Zimbabwe has the ability to rise up again especially with the internationally accepted new government of Unity were the two major political parties, ZANU PF and MDC have come together to work as one for the betterment of the country and to fulfil the needs of the people. There has been little to no investment in Zimbabwe as many pulled out during the past decade. Foreign investment is when a company invests financially in a country abroad, whether in the form of portfolio investments which include shares, stock and bonds, or in the form of direct investment where locally based operations are owned and controlled by the foreign investing corporation. Such investments are controlled by laws known as International trade laws. International Trade law includes the appropriate rules and customs for handling trade between countries or between private companies across country borders. Most countries are part of a body that has made an agreement for trading internationally. Zimbabwe is part of several including UNICTRAL (United Nations Commission on International Trade Law), BIPPA (the Bilateral Investment Promotion and Protection Agreement) and COMESA (the common Market for Eastern and Southern Africa). Zimbabweââ¬â¢s local body, governing foreign investment is the Zimbabwe Investment Authority with approval necessary from the Reserve Bank of Zimbabwe and Registrar of companies. The extract below shows the depths to which the Zimbabwean economy had fallen. Foreign Direct Investment Statistics 52. Zimbabwe Net Investment Flows 1998-2007 (US$ million) |1998 |1999 |2000 |2001 |2002 |2003 |2004 |2005 |2006 |2007 | |Direct Investment |436 |50 |16 |0 |23 |4 |9 |103 |40 |69 | |Portfolio Investment |11 |21 |-1 |-68 |-2 |4 |2 | | | | |Source: IMF, UNCTAD, Ministry of Finance However, what is common is that Africa is the one continent that most global capitalist powers compete for due to its vast resources and wealth, examples eing of Nigeria and its oil, The Congo, Zimbabwe, South Africa and Botswana for their diamonds and precious stones as well as many other aspects such as Tourism. Zimbabwe to one of the Wonders of the world, and some people like investing in tourism, but over the past decade they decided not to. Countries would have loved to do that for reasons such as the 2010 world cup but in as much as opportunities arise, if a country is not politically and e conomically stable, it becomes almost obsolete to even the most interested investors. Zimbabwe economic situation was is dismal, having the ââ¬Å"largest peacetime drop [in GDP] ever recordedâ⬠(http://www. state. gov/e/eeb/rls/othr/ics/2009/117167. html) at roughly 50%. The Economist Intelligence Unit (in the USA) estimates that 12. 8% of the GDP dropped in just one year- 2008. The inflation rate is the highest in the world, officially estimated at about 231 million percent in July last year. Unofficially however, inflation rates of the Zimbabwean dollar are said to be hundreds of billions if not quadrillions; and this is only the tip of the ice berg. The reasons why foreigners had pulled out were because of: the instability that was brought about after the land return programme â⬠¢ political instability ââ¬â divisions between the two parties and how that affected the country â⬠¢ Economic sanctions ââ¬â these can cripple a whole economy and country â⬠¢ the breakdown of the stock exchange â⬠¢ the non transparency of the companies and thei r involvement with government â⬠¢ high taxes â⬠¢ unprofitable economic environment â⬠¢ inflation that started in the thousands and ended in the millions â⬠¢ the laws and regulations governing foreign investment â⬠¢ limited protection for foreign investors in some cases â⬠¢ corruption The biggest problem the country was facing is that the rule of law no longer exists in the country. Instead, numerous government policies were ill formed and passed. Some that totally nullifies the power of law and order and in some cases, human rights. Currency exchange is a crucial part of foreign trade, the governmentââ¬â¢s Conversion and Transfer Policies were uncertain and changed unexpectedly several times. This has put a constraint on business planning and operations and most companies would much rather not risk making great losses because of a sudden adverse change in policies. The government of Zimbabwe had been known to disregard any judgments passed against them by international arbitrators, making the country a place full of lawlessness, dangerous and too risky to invest in. For example in 2005 ââ¬Å"a group of Dutch farmers whose farms were seized under the land reform program took their case to the International Centre for Settlement of Investment Disputes (ICSID), demanding that the Zimbabwean government honour the BIPPA between the Netherlands and Zimbabwe. Although the government ââ¬Å"acknowledged that the farmers had been deprived of their land without payment of compensationâ⬠they disputed the US$30million claim by the farmers. A decision is yet to be reached. A policy amendment Constitutional Amendment 17, enacted in 2005, removed the right of landowners whose land had been acquired by the government to challenge the acquisition in court. To increase foreign investment the governmentââ¬â¢s priority should be to restore the rule of la w and order. Restore the peopleââ¬â¢s faith in the power and fairness of the judicial administrations and government of Zimbabwe. They can do this by honouring their agreements with other countries and renouncing past policies that contradict initial agreements. It would be messy but the country itself is already in a bad state. Righting the wrongs is therefore being an important part of reviving the nationââ¬â¢s economy. Nepotism, favouritism, victimization, and discrimination would have to be seen as no longer existent in the country to make investors feel once again confident and safe investing Zimbabwe. According to the ââ¬Ëbest available surveysââ¬â¢ ââ¬Å"only 7% [700 000 people] of the nations population is employed in the formal sector,â⬠otherwise there is 80% unemployment in the formal sector. Most qualified workers have fled the country in search of greener pastures. The government rightly expects foreign investors to maximize use of local managerial and technical personnel. But in my opinion it is the governmentââ¬â¢s responsibility to ensure that such personnel are available. Their policy making should therefore first focus on educating and catering for its people so they are available and up to international standard when foreigners come to invest and need workers. The government should make policies that direct a lot more funding into the Educational sector of the country ââ¬â which was once very well respected and recognised. Those way investors would find more ready, capable and qualified locals to employ. The government should improve the health sector by injecting funds to pay doctors and nurses well. Qualified health workers flee Zimbabwe as soon as they get the chance in search of better, more consistent work environments. With well paid doctors and health personnel the country could avoid crises like the cholera outbreak in 2008 and ensure a safe physical environment. In all this however, Zimbabweââ¬â¢s government has made efforts to improve foreign investment. They have created foreign trade zones and processing ports. Benefits include 5 year tax holiday, duty free importation of raw materials and capital equipment for use in the EPZ. There is a requirement to export 80% of production in these zones however so this makes the offer less attractive to foreign investors. The government should consider reducing the stipulation in order to attract more investors. After the formation of the Government of National Unity, there was increased support from the international world on how to come up with a sound political framework and policy formulation that could encourage foreign investors, and true to form, the two parties have been trying to work with each other so as to do so. South Africa and Botswana, although closer to home than the usual British and American investors, have already started investing in the mining and farming sectors, with notable billionaires such as Patrice Motsepe of South Africa playing a crucial part in the field. The goals business sector itself is pushing for: 1. Transparency in business and transactions 2. Sustainable taxes for investors 3. Regulatory laws that also work favourably for foreigners 4. Strict function and control of the 49% foreign ownership and 51% Zimbabwean ownership ââ¬â where even those that are foreigners and own 49% are allowed to make Zimbabwean colleagues, their managers and CEO's for the sole issue of trust among many things. Such partnerships are being encouraged. The stock market for one is back on track, especially with the use of the US dollar and South African rand which is making the market stable and opening up the incentive of investing as there is no longer inflation after the current none use of the Zimbabwean dollar. For the mean while, it is not being used although it has not been eradicated as it will be back in use once the environment is permitting. The policies government makes should firstly, show that the country is serious about attracting foreign investment ââ¬â at the moment, it looks like South Africa, Egypt, Ghana and Nigeria are the only serious ones. Countries like Botswana, Uganda and Kenya are countries that are coming up and under observation in the mean time. Secondly the policies should market Zimbabwe as aggressively as other regions of the world ââ¬â because as of now there is need for a supportive business framework such as transportation and communications infrastructures, trained or trainable human resources, and equitable trade and employment practices. Thirdly they should be aimed at demonstrating to investors the opportunity cost of not investing in Zimbabwe. Previously the government has certain policies in place, formed and implemented under a dictator regime; In 2008 the government introduced an Indigenization Act that mandates, over time, 51 percent indigenous ownership of businesses. The government reserves several sectors for local investors. Under current laws, foreign investors wishing to participate in these sectors may only do so by entering into joint venture arrangements with local partners. The foreign investors are allowed to own 35 percent of the operation. The following industries face these restrictions; â⬠¢ Agriculture/Forestry; Primary production of food and cash crops , Primary horticulture , Game, wildlife ranching and livestock, Forestry , Fishing and fish farming, Poultry farming , Grain milling , Sugar refining. Transportation; Road haulage, Passenger bus, taxis and car hire services of any kind, Tourist Transportation, Rail operations. â⬠¢ Retail/wholesale trade; including distribution, Barber shops, hairdressing and beauty salons, Commercial photography, Employment agencies, Estate agencies, Valet services, Manufacturing, marketing and distribution of armaments, Water provision for domestic and industrial purposes, Bakery and confecti onary, Tobacco packaging and grading post auction, Cigarette manufacturing. Source: (www. nationsenclclopedia. om/economies/africa/zimbabwe/foreign-investment). . The government needs to recognise that this may not be adequate enough incentive for investors. They should therefore revaluate and review their policies in some areas to encourage foreigners to invest. The percentages given to foreigners may prove unprofitable to a large conglomerate looking to run a company based in Zimbabwe. They would rather invest in a place where returns can be maximized, and the government should therefore allow foreigners a larger percentage of the business. he Government of National Unity has taken this into consideration and opened its door to all country stakeholders in 2009 to be part of the new policy making process, this included miners, lawyers, pastors, NGOââ¬â¢s and many other diverse groups. This reflected the positive determination of Zimbabweans and the government to get back on rein vest itself bigger and better. Our president was quoted at a mining conference to attract foreign investors who are sceptical about Zimbabwe's respect for property rights following the disruptions on commercial farms and a raft of controversial indigenisation laws; Because it is capital intensive, the mining sector requires regional and international partners who can bring in the necessary capital, à mining technology and management expertise to complement local resources,â⬠Mr Mugabe told about 200 foreign investors. ââ¬Å"On its part, the government is committed to ensuring that the policy environment is stable, predictable and sufficiently attractive to guarantee investors good returns on their investment. ââ¬Å" Investors and locals alike look forward to the growth our economy will experience because of the new policies being put in place and the effort of our Government of National Unity is making to involve all stakeholders and uphold those laws. References: ? http://allafrica. com/stories/200909180530. html ? http://www. allbusiness. com/trade-development/trade-development- ? NationsEncyclopedia. com ? www. zimtrade. co. zw ? www. zia. co. zw ? http://www. state. gov/e/eeb/rls/othr/ics/2009/117167 ? www. hg. org/trade. html ? en. wikipedia. org/wiki/United_Nations_Commision_on_International_Trade_Law
Tuesday, October 22, 2019
Teen Alcoholism essays
Teen Alcoholism essays Too many college students have just one objective, to get drunk! Campus alcoholism is an epidemic sweeping through colleges and universities at a rapidly growing speed. Even though it is illegal for a minor under the age of 21 to purchase or consume alcohol, that law has never stopped those who wished to drink. What used to be a social activity has radically changed to an unsafe pass time that eating away at students money, school and health. A Harvard study showed that in 1993 only 38% of students who drank, drank to become drunk. That number jumped to 52% who drink to become drunk, when polled in 1997. Yet alcohol is addictive for only a minority - an estimated 10 percent in the United States - of it users. For most drinkers alcohol is a relatively harmless social beverage. Even though the percent is small, too many students are spending weekends and weeknights drinking the nights away. Time is not the only commodity that kids are wasting on alcohol. Research shows that college students spend 5.5 billion dollars a year on beer and alcohol. That is over four billion cans a year and 430 million gallons annually. All that alcohol is enough for every college and university in the U.S. to feel an Olympic size swimming pool. Alcohol is an infinitely confusing substance. In small amounts it is an exhilarating stimulant. In larger amounts it acts as a sedative and as a toxic, or poisonous, agent. When taken in very large amounts over long periods of time, this combination chemical and drug can be damaging to cells, tissues, and organs. To further the confusion, alcohol is the only drug, which can also be classified as a food. Rich in calories and a potent source of energy for the body, alcohol is used by the cells to perform their complicated functions. Unlike most foods, however, alcohol contains negligible amounts of vitamins and minerals and contributes little or noth ...
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