Diabetes And Pregnancy Essays - Diabetes, Gestational Diabetes

Diabetes And Pregnancy Deciding to have a child is one of the most important decisions of people's lives. Diabetes is a very serious disease. It attacks million people around the world many of them women. These women one day may be thinking about having a baby. Numerous precautions must be taken by women during pregnancy. Special safeguard must be taken by women with diabetes. These precautions need to be taken due to birth defects. "An estimated 1.5 million women of child-bearing age in the United States have diabetes. A diabetic pregnancy is one of the leading causes of birth defects." (Henderson pNA) Diabetes can strike at any age and can occur in anyone. Although it is not exactly known for sure about the what causes it. Diabetes is believed to do with the body's own immune system attacking and destroying insulin producing cells in the pancreas. There are two forms of Diabetes, Type I diabetes, also called insulin dependent diabetes. The second form, Type II diabetes, or non insulin dependent diabetes. Before insulin was introduced women with diabetes were told that pregnancy was not for them. It is true that in the past, pregnancy did present major problems for women with diabetes. In the pre-insulin era, "Many diabetic women died before the child bearing age and those that survived were often infertile." (Ellenberg 696) Their babies did not often survive. When insulin became available in the 1920's, pregnancies became more common with diabetic women. Yet, the number of successful pregnancies remained far below that of women who did not have diabetes. Today Tabarez 2 the news is good, It is now known that the key to a healthy pregnancy for women with diabetes is tight blood glucose control. The goal of tight control is to keep blood glucose levels as close to non-diabeteic or normal as possible. Although the rate of successful pregnancies among women with diabetes has improved, there are still some problems with to be concerned about. "Pregnant women are who are insulin dependent Diabetic are more likely to deliver children with birth defects and more likely to deliver stillborn then the general population. They also have a much higher rate of miscarriages." (Casson I.F. 275) We now know that many birth defects are related to the mother's blood glucose control during the first eight weeks of pregnancy. What is important to note is that many women may not even know they are pregnant at this time. For women who have diabetes or with any pregnancy, the solution to this problem is obvious. You must plan ahead for your pregnancy. If you are a diabetic and don't already practice good diabetes control regularly, your priority should change. "Patients with pre existing diabetes require intensive insulin therapy before conception and during pregnancy. Glucose self monitoring assists in achieving near normal glucose levels during pregnancy." (Pasui, K. 273) Women should maintain good blood glucose control three to six months before she plans to become pregnant. Another problem that rarely occurs is stillbirth. The baby dies before birth, still births used to occur more frequently among women with diabetes. But now, with care and good diabetes control the chances for still births are low. One more problem , called jaundice, is common among all babies. But increase more so among those born to women who have diabetes. Jaundice is a yellowing of the skin caused from a waste Tabarez 3 product. Before birth the baby needs a large supply of red blood cells. However, at birth the baby no longer needs this supply. The baby's body will work through the liver to break down and excrete the old red blood cells. If the baby's liver is not mature enough, it may have trouble handling this work load. The broken down red blood cells are called bilirubin. Instead of being excreted, bilirubin is deposited in the baby's tissues. Bilirubin is what colors the skin yellow. Babies with jaundice are sometimes treated by being exposed to special lights. The lights help break down and get rid of bilirubin. "Treatment of the problem is usually by photo therapy but exchange transfusions may be necessary." (Hollinssworth, D.R. 266) But high levels of bilirubin becomes toxic. A baby might need a blood transfusion, but the chance of this happening is rare. Finally, as women consider pregnancy, they must realize that managing diabetes during pregnancy is time-consuming and expensive. There will be more doctor visits, special tests, more frequent blood glucose testing, and more insulin injections each day. There will also be more time away from work.

Bald Eagles And Golden Eagles Essays - Eagles, Bald Eagle

Bald Eagles And Golden Eagles Essays - Eagles, Bald Eagle Bald Eagles and Golden Eagles Eagle is the common name for a number of diurnal birds of prey, some of which are the largest members of their family which also includes kites, hawks, buzzards, and certain vultures. The name eagle is somewhat loosely applied, as several of the groups are not particularly closely related to one another, and some birds called hawks are larger than some called eagles. The Bald Eagle (Haliaeetus Leucocephalus) and the Golden Eagle (Aquila Chrysaetos) are two eagles that have several of the same characteristics and have several different ones as well. The Bald Eagle is the only eagle species living strictly in North America, and has a presence in every state in the US except Hawaii. Young (immature) Bald Eagles are light gray when hatched, and turn dark brown before leaving the nest at about 12 weeks of age. During their third and fourth years, Bald Eagles have a mottled brown and white color under their wings and on their head, tail and breast. The distinctive white head and tail feathers do not appear until they are 4 to 5 years old. Bald Eagles range from about 29-42 inches long, and can weigh between 7-16 pounds, and have a wingspan of 6 to 8 feet. This makes them one of the largest birds in North America. Bald Eagles residing in the northern US are larger than those that reside in the south. They have a life span of up to 30-40 years in the wild and longer in captivity. Bald Eagles are monogamous and remain faithful to their mate until death. Females lay one to three eggs annually, and the incubation period is approxim! ately 35 days. Only about 50% of Eagles hatched survive the first year. Strong endangered species and environmental protection laws, as well as active private, state and federal conservation efforts have brought back the USA's Bald Eagle population from the edge of extinction. There are now about 4500 nesting pairs and 20,000 total birds in the lower 48 states, and there are over 35,000 Bald Eagles in Alaska. America's Bald Eagles are back in strong numbers today, but they are still a "threatened" species in the lower 48 states. Breeding season last from November to April. Bald eagles mate for life and use the same nest each year. They build a huge nest (aerie) of sticks and twigs in a tree, or on rocky cliffs and average in size of 2 feet deep and 5 feet across. The nest takes weeks to construct and is increased yearly. Eventually some nests reach sizes of more than 10 feet wide and can weigh several tons. Bald Eagles feed primarily on fish, but also eat small animals (ducks,! coots, muskrats, turtles, rabbits, snakes, etc.) and occasional carrion (dead animals). Eagles swoop down to seize fish in their talons and carry it off, but can only lift about half of their weight. Bald Eagles can even swim to shore with a heavy fish using their strong wings as paddles. However, it is also possible that they can drown if the fish weighs too much. The Golden Eagle is a large brown and golden colored eagle that can be found in a variety of habitats in the western North America region including mountainous areas, canyons, shrub-land and grasslands. The Golden Eagle can also be found in Europe, Asia and northern Africa. The breeding range in North America includes north central Mexico, the western United States as far east as the Dakotas, Kansas and Texas, also Alaska, and across northern Canada. This bird of prey can weigh up to 15 pounds and can have a wingspan of 6 to 8 feet and a length of 30-40 inches. Females are often more noticeably larger than males as is true with most birds of prey. Young (immature) Eagles have a patch of white on the tail, and the adult tail is gray and brown. The Golden Eagle also builds large their nest out of sticks and twigs in a tree or on a cliff. The female lays 1-4 eggs (usually 2) and often does most of the incubation. The males provide most of the food while the females feed and tend! the

Customer Service Excellence Essay Example | Topics and Well Written Essays - 2750 words

Customer Service Excellence - Essay Example This gradually led to the awareness that employees are the contact point and they need to be fully taken care before expecting them to take care of the customers. This gave rise to the term internal customers (employees) and hence the term internal marketing or IM came into existence. Today organizations use different techniques to keep the internal customers happy as a long-term strategy. Internal marketing, according to Kotler (1991) includes successful hiring, training, motivating and remunerating able employees (cited by Vella, Gountas & Walker, 2009). Thus to achieve the service quality the internal customers should be developed effectively first. It is assumed that effective internal marketing will lead to employee satisfaction which in turn impacts the service quality. If the staff are friendly, helpful and generally agreeable it influences customer views of service quality. Internal marketing (IM) is viewed as the application of all external marketing orientation philosophy t o all internal organizational and HRM processes. IM is the activity that connects internal customer or employees with all external service activities. Employees are not merely part-time marketers but they are the first set of customers that need to be satisfied fully. IM was considered as a possible solution to the challenge of delivering consistently high service (Khan & Matlay, 2009). IM is a business philosophy which lays emphasis on developing, encouraging, understanding and valuing the employees. Internal customers’ needs must be first met before a firm can successfully satisfy the external stakeholder needs. The concept and practice of internal marketing is based on the premise that employees as customers would feel committed and motivated, cooperative and enthusiastic (Mudie, 2003). Service quality can be impacted by three service factors – service orientation, service adaptability, and flexibility to manage service demand with frontline staff supply (Vella, Gou ntas & Walker, 2009). Adaptive and flexible organizations can create better work environments leading to higher job satisfaction and stronger customer relationships. If the employees are not treated well many IM strategies such as service orientation may fail. Since the service brand depends upon employees’ attitudes and behaviours, investment in internal service factors (ISF) should not be compromised as this could negatively impact the achievement of customer service excellence. To keep the internal customers satisfied reward systems, motivational techniques, training and recruitment policies should exist because these enable the external customer oriented marketing to succeed (Vella, Gountas & Walker, 2009). Customer service excellence can be achieved by allowing individuals and teams within organizations to explore and acquire new skills in the areas of customer focus and customer engagement (CSE, n.d.). This suggests that internal customers or employees should be focused upon; their skills need to be enhanced. This is known as internal marketing where the internal customers are first satisfied because it has strongly been advocated that satisfied employees can deliver enhanced service to external customers. To deliver excellent service requires focused and effective organizational and institutional processes. Employee training can lead to prosocial behaviour, which Chebat, Babin and Kollias (2002) consider essential because the front line staff are the first customer

Christian Marrige Term Paper Example | Topics and Well Written Essays - 2250 words

Christian Marrige - Term Paper Example entire blame on themselves for anything going wrong, thinking they could have done something to avoid it and it was their own shortcomings that led the event to take place. On the other hand, persons with character-disorder will put the blame on everyone and everything other than themselves, thinking that it is their environment that caused things to go wrong and that they had no part to play in it at all. On a personal level, neurotic personalities suffer from a sense of inferiority, which leads them to become over-achieving individuals, who try to control everything around them and often over-compensate in all aspects of their lives, as they believe that they can, rather they should, always do more. Character-disordered personalities, however, have a sense of powerlessness; they feel that they cannot control anything and that no matter what they do, it is actually factors outside themselves that cause things to happen the way they do. Thus, the neurotics are constantly harming themselves by their actions, while those with character-disorder are harming those around them: the former blaming themselves and being hard on themselves, and the latter blaming those around them and being hard on others. On a grander scale of things, neurotics cause exasperation in those around them, however, with a little bit of help from their loved ones they can overcome this habit, as they are always open to growth; keeping in mind their low self-esteem, they are more open to the ideas and thoughts of others. Character-disordered people, however, are not open to criticism at all; they never apologize for their behavior as nothing is ever their fault – they always have some outside force to blame. Thus, it is very hard for the neurotics to fall in love as they find fault in themselves, whereas the character-disordered personalities simply cannot love because of their passive aggressiveness as well as due to their deflection of blame on those around them. The most marked

Compare and contrast the Virginia and New Jersey plans presented at Essay - 2

Compare and contrast the Virginia and New Jersey plans presented at the Constitutional Convention - Essay Example This paper compares and contrasts the two plans. Virginia plan proposed a congress with two houses or chambers namely lower house and upper house and each state to be represented depending on its size and population. On the other hand, New Jersey plan proposed single chamber legislature (unicameral) where every state represents one vote without considering the size and population. Virginia plan proposed that one chamber of the legislature have a representative elected by the people. It also suggested that the state legislature to nominate members of the second chamber. However, New Jersey Plan did not propose how congress members are selected. Virginia plan proposed that members elected by the people serve for three year terms and the other house elected by state legislatures serve for seven years. On the other hand, New Jersey plan did not propose the length of terms of service for the legislative branch. Virginia plan proposed that state members be based on the population of the states. Hence, bigger states were to have more state members than smaller ones. On the other hand, New Jersey plan proposed that states be treated equally with each having the same number of members. Virginia plan proposed executive and national judiciary to have power to veto legislation that was subject to override and a national veto power over any state legislation. It also gave legislative branch powers to negate state laws, which were incompatible with the articles of the union. On the other hand, New Jersey plan proposed congress to have more powers of making laws and take precedence over state law. It also proposed congress to have more powers of setting and forcing the collection of taxes. In both plans, the federal government and states work together and relates in different aspects. For instance, they both proposed federal government to

Development of Parallel Parking System

Development of Parallel Parking System Executive Summary Introduction/Background Traditionally development of microprocessor based control systems involved the following steps. The control algorithm was designed by a systems or a control engineer. The algorithm would then be coded in programming languages like assembly, C or C++ which would be implemented on a microprocessor based hardware the controller. The problem with this method was the verification of the algorithm would be possible only once the whole system was developed. Any errors in design would prove extremely costly. Also in converting control logic specification into software there is a high probability of translation errors that would lead to erroneous results. mModel Based Design is a software methodology which addresses these issues and is gaining a lot of popularity currently in the industry. The scope of this project is to apply the Model Based Design methodology to develop a control algorithm that eases the parallel parking of a car problem for a novice driver. Aims and Objectives The aim of this project is to develop a parallel parking system using Model Based Design. The objectives are to understand the parallel parking problem and methods to solve it, steps involved in Model Based Design and explore the possibility of implementation of a parallel parking algorithm on a Lego Mindstorms Robotics Kit. Acheivements A fuzzy logic based parallel parking algorithm was successfully simulated. Model Based Design concepts were explored and implemented in the design. Programs developed in Simulink were successfully tested on the Lego Mindstorms KIT using Real Time Workshop Embedded Coder, EC Robot Toolbox, nxtOSEK and other associated tools. Conclusions/Recommendations The parallel parking strategy implemented did show good results. However, real life scenarios may be different than the one discussed. For example, the controller depends on wall following. This implies there has to be 3 sides closed in a gap for the parking controller to work. The development of the algorithm was with the intent of being able to execute it on a Lego Mindstorms Kit. However, there were some issues regarding this. The main being lack of a floating point unit on the NXT Brick. Though it is possible to execute floating point programs on the NXT, it causes severe performance issues. The controller developed used the fuzzy logic blockset which inherently uses a lot of floating point variables. One method to overcome this draw back could be developing a fixed point version of the fuzzy logic blockset. Other parking strategies involving classical control could be experimented with Lego Mindstorms. Complex tasks like path planning could be executed on a computer communicating with the NXT via Bluetooth and the control tasks could be implemented on the NXT using fixed point math. Introduction Problem Description The parallel parking manoeuvre of a car has been a topic of academic and industry interest. The car or a car-like mobile robot hence referred to as CLMR has inherently a constraint known as a nonholonomic constraint. This is problem can be summarised as follows (Pushkin Kachroo and Patricia Mellodge, 2004.). If a system has restrictions on its velocity, but those restrictions does not cause restrictions in its positioning the systems is said to be nonholonomically constrained. Viewed in another way, the systems local movement is restricted, but its global movement is not. Mathematically, this means that the velocity constraints cannot be integrated. For e.g. during a parallel parking manoeuvre, when a driver arrives next to a parking space, he cannot simply slide his car sideways into the spot. The car is not capable of sliding sideways and this is the velocity restriction. However by moving the car backward and forward and turning the wheels the car can be moved into the parking space. Ignoring the restrictions caused by the external objects the car can be located at any position with any orientation, despite the lack of sideways movement (Pushkin Kachroo and Patricia Mellodge, 2004.). The challenge in this project is to not only address the parallel parking problem but also to develop it using advanced software design techniques involving Model Based Design Literature Survey The parallel parking problem can be viewed as a subtask of robot motion planning and control. There is has been considerable research in this area. De Luca et al (1998) classifies all robot motion tasks into 3 subtasks as follows. Point-to-point motion: The robot must reach a desired goal configuration starting from a given initial configuration. Path following: The robot must reach and follow a geometric path in the Cartesian space starting from a given initial configuration (on or off the path). Trajectory tracking: The robot must reach and follow a trajectory in the Cartesian space (i.e., a geometric path with an associated timing law) starting from a given initial configuration (on or off the trajectory) A parallel parking problem can then considered as a point to point motion task or a path following task and a feedback control law if proposed for the same. (Dongbing and Huosheng 2000) have developed more advanced control strategies involving Generalized Predictive Control and Neural Networks based predictive control. Fuzzy Logic based controllers have also been used to solve the parallel parking problem. Shih-Jie and Tzuu-Hseng (2002) proposes a rule base based on the distance of the CLMR edges to the parking spot. Kuang-Yow et al (1999) proposes a fuzzy sliding mode controller to solve the parallel parking problem. Holve and Protzel (1996) suggest another fuzzy logic based controller and a parking algorithm based on human experience. It involves finding an appropriate space for parking, stopping at the right place, executing the parking procedure and to do so without colliding with any obstacles. Summary The classical control methods discussed above are generally more complex compared to other ones. Most of them rely on trajectory generation and then a control algorithm for trajectory tracking or path following. The success of the algorithm in a real time implementation also depends upon the accuracy of the positioning systems which increases the complexity and the hardware cost of this method. While the fuzzy logic based controllers are more intuitive and easier to design the performance is suboptimal compared to the classical controllers. But they are more robust to sensor uncertainties (Holve, R. Protzel, P. 1996). The goal of this project is to develop a parallel parking algorithm suitable for implementation on a Lego Mindstorms robotics kit. Being able to solve the parallel parking problem and take this design rapidly from concept to implementation is the motivation behind this project. Parallel Parking of a Car like Mobile Robot (CLMR) Introduction The following chapter discusses the kinematics model of a CLMR and investigates a feasible parking strategy using a fuzzy logic based controller. Kinematic Model of a CLMR The kinematic model of a CLMR is as shown (Shih-Jie and Tzuu-Hseng 2002).The model assumes that the car wheels are in contact with the ground at all time i.e. no slip exists. : is a mid point on the rear axle of the car : is mid point on the line joining the front wheels : is the angle between the X axis with respect to the vehicle frame : is the steering angle with respect to the vehicle frame : is the distance between the front and rear axle The non-holonomic constraint equation is given by (2.1) The equation of the rear wheel is given by (2.2) (2.3) (2.4) The relationship between the rear and the front wheels are given by And (2.5) (2.6) The above equations are useful while finding the future positions of the CLMR. The physical layout of the CLMR is a three wheeled one. A three wheel robot and a four wheeled one have the same non- holonomic constraint. A three wheeled robot is chosen here for simplicity. The sensor positions are chosen with the assumption that the parking position is always going to be to the right of the vehicle. 4 ultrasonic sensors are used. 2 sensors (s2 and s1) are placed on the right front and rear edge and the other 2 (s3 and s0) are placed at the front and rear sides of the car as shown in the Fig 2.2. The position of sensors s1 and s2 with respect toand described by the following equations. S1 (2.7) S2 (2.8) The position of the sensors is used to determine the distance of the CLMR from an obstacle during simulation. Parking Strategy The parking strategy is developed intuitively as a human driver would do. The assumption is that a parking spot is somewhere to the right side of the vehicle to be parked (Holve and Protzel,1996). The vehicle would be moving parallel to the line of cars. The algorithm is as follows. Search for an obstacle free area on the right side of the car. The distance should be greater than the minimum distance required to park the car. This could be set at twice the length of the car. Once a sufficiently large parking spot is found, the car is reversed into the gap using a wall following algorithm. This algorithm aligns the car as parallel as possible in the gap without colliding with the rear wall. The car is then driven forward to align itself in the centre of the gap. Steps 2 and 3 can be repeated until the desired position is reached Wall Following Controller (Shih-Jie and Tzuu-Hseng , 2002) The heart of the parking strategy is a wall following controller. Shih-Jie and Tzuu-Hseng (2002) proposes a fuzzy logic scheme as follows. The variables shown in the figure represents the following d1 distance between the rear end of the CLMR and the wall d2 distance between the front end of the CLMR and the wall Dist is the desired distance between the wall and the CLMR The objective of the controller is get d1 equal to d2 which is the desired distance from the wall Dist . The scheme suggested is a 2 input one output scheme which controls the steering angle of the CLMR. Since the CLMR in this project is a three wheeled one the turning is done by varying the speeds of each wheel. The input variables to this control scheme are as follows if the CLMR is moving forward . Input1 = d2 Dist (2.9) Input 2 = d2 d1 (2.10) and if the CLMR is moving backward Input1 = d1 Dist (2.11) Input 2 = d1 d2 The output of the controller is the amount by which the CLMR needs to turn in a given direction. The fuzzy membership functions for Input1, Input2 and Steer are shown below The membership functions are equally divided triangular membership functions. The Rule Base for the wall following is shown in the table below. It is based on sliding mode control (Li et al, 2000) The rules can be an represented linguistically as If (Input1 is Positive Big) and (Input2 is Negative Big) then (steer is Zero) If (Input1 is Positive Big) and (Input2 is Negative Small) then (steer is Positive Small) and so on 25. If (Input1 is Negative Big) and (Input2 is Positive Big) then (steer is Zero) The defuzzication method used here is centre of gravity which is good for fine control The final fuzzy logic entire controller can be summarized as follows Summary With the kinematic equations of the CLMR and the equations describing the sensor positions, a model can be constructed. With the parking strategies and a fuzzy logic controller now developed we shall discuss an efficient methodology in taking these designs into implementation. Model Based Design Methodology Overview The advances in microprocessor technology in the early 70s brought about a change in the way control systems were developed. From electrical relays built into ladder like networks and programmable logic controllers , controllers were being developed around a computer built with adequate hardware and software. Traditionally most of these control software development was based on paper designs and manual programming followed by verification activities such as code inspections and a unit/integration test (Guido Sandmann and Richard Thompson 2008). Many of these activities lack tool automation, and are very time consuming. Thus they are error prone and time consuming. Lack of tool chain integration provides another opportunity for errors to be injected into the software that are often detected late and at high costs to the development process and so involve manual interaction. Model Based Design is software design methodology used to address these issues. The steps involved are in MBD ,some of the commercially available tools and the tool chain choices for this project are discussed below Model Based Design Process The Model Based Design process can be divided into the following steps (NI Developer Zone, 2006). System Definition System definition involves the design process of a particular problem in consideration. It is mostly a conceptual design where in the problem and solutions are analyzed. Modelling Simulation The step implies that the analyzed design is simulated using a graphical based simulation tool. MATLAB-SIMULINK, ASCET-MD etc are some examples of modelling tools. Designs here can be easily changed verified and re designed if necessary. Rapid Prototyping If the hardware of production controller is not available during the design phase a generalized hardware controller maybe used to test some of the simulations. This is the rapid prototyping phase. Targeting Targeting refers to getting the software code executing on the production hardware. This stage involves the use of auto coders tools that generate C code directly of graphical models, cross compilers and other tool chains that facilitate this. Hardware in the loop Testing Hardware in the Loop testing is used while developing control strategies for plant models like engines. It provides real time simulation of a real world plant model. System Testing This is the last step in the design process wherein the controller is tested on the real plant. Summary Of the stages in Model Based Design discussed above, only the most relevant one will be applied to this project. Beginning with system definition, modelling simulation proceeding to targeting and finally onto system testing will be the stages followed in this project. MATLAB/SIMULINK, Stateflow, Virtual Reality Toolbox, Fuzzy Logic Blockset would be the tools used for modelling and simulation while Real Time Workshop Embedded Coder would be used during targeting. A detailed list of other tools will be dealt in the next chapter. Introduction Lego Mindstorms NXT is a robotics kit which consists of mechanical building blocks and electronic sensors. The highlight of this kit is the programmable brick called the NXT. The NXT is a 32bit ARM7 based microcontroller which allows motors and electronic sensors to be easily interfaced .Users can also run custom programs written via a GUI based programming language. The language provided by Lego, though very simple and intuitive to use does not exploit the true potential of NXT. Over the years, advanced users of the Lego Mindstorms have been successful in creating custom tools that apply every imaginable concept of embedded systems. The following chapter discuss some of these software tools and hardware details relevant to this project. The most important part of this is to be able to design , simulate and test the robot using MATLAB Simulink. Ultrasonic Sensor The Lego Ultrasonic Sensor is shown below. It is mainly used for distance measurement. It has a range of 255 cm and is accurate to about +/- 3cm One of the tasks of Model Based Design is to be able to program the NXT from Matlab Simulink environment. The tools required to automate this process are discussed below John Hansens Enhanced Firmware Firmware in embedded systems term is referred to the basic software that is initially run on a hardware device. It performs basics factions like initialization of devices , integrity checks on memory and so on similar to BIOS on a standard PC. The NXT brick , out of the box , has a standard firmware installed. This is designed to be used with the software provided. In order to write programs in C and realize the true potential of the NXT, a custom firmware has been written by John Hansen. This allows the NXT to be programmed by either using the provided software or by programming in C and using other tools which will be explained later. The NeXTTool The NeXTTool is a program that allows communication between the host PC and the NXT brick. It can do various tasks, but most importantly it is used to download custom programs onto the NXT. The nxtOSEK nxtOSEK (previously known as LEJOS OSEK) is an open source real time operating system for LEGO MINDSTORMS NXT. It contains device drivers from leJOS NXJ, an open source program that allows users to write Java programs on the NXT and a real time operating system source know as a TOPPERS OSEK. C or C++ can be used to write custom programs and compiled with the nxtOSEK using the GCC tool chain (Takashi Chikamasa, 2008) The Embedded Coder Robot NXT Blockset is one of the key elements in applying Model Based Design Techniques to the Lego Mindstorms NXT. These blocks are custom Simulink blocks used in the controller side and serve as inputs and outputs to the real world. A word of caution. Custom blocks especially hardware related blocks behave different behaviour in simulation and code generation . For e.g. an ultrasonic sensor block will not directly give sensor readings. The behaviour of the ultrasonic sensor will have to be separately emulated. During code generation process, a function call to the ultrasonic device is placed where the block is used. This ensures the program using the block gets the value directly from the sensor. The details of the blocks used for this project are discussed below There are two blocks that have to be for an ultrasonic sensor blocks consist of two blocks. The Ultrasonic Sensor Interface block and the Ultrasonic Sensor Read block. Servo Motor Blocks Fig 4.5 Servo Motor Blocks The working of the Servo Motor is similar to the ultrasonic block as explained above. The details of the block are given below. Data Type int32 Dimension [1 1] Data Range 0 to 255 [cm], -1 (the sensor is not ready for measurement) Port ID S1/S2/S3/S4 Summary Tools concerning with the implementation of a Matlab Simulink design on a Lego Mindstorms NXT were explored here. However the most important of all is to simulate a working design. The next chapter discusses the implementation of the parallel parking strategy and the simulation results. Parallel Parking Simulation An integral part of Model Based Design is being able to simulate and get the desired results before implementation. The following chapter discusses the results of the controller developed in Chapter 2. For verification of the controller a Simulink model developed by Takashi Chikamasa, (2006) was used. The model was of a 3 wheeled robot with the motor dynamics included. A 3-D environment was provided using the Virtual Reality Toolbox. The environment however has been changed to suit the parallel parking problem. Parallel Parking Strategy The controller algorithm was developed in Simulink using Stateflow and the Fuzzy Logic Toolbox. A 2-D plot of the trajectory path traversed by the CLMR is shown below. Conclusion and Recommendations The parallel parking strategy implemented did show good results. However, real life scenarios may be very different. For example, the controller depends on wall following. This implies there has to be 3 sides closed in a gap for the parking controller to work. The development of the algorithm was with the intent of being able to execute it on a Lego Mindstorms Kit. However, there were some issues regarding this. The main being lack of a floating point unit on the NXT Brick. Though it is possible to execute floating point programs on the NXT, it causes severe performance issues. The controller developed used the fuzzy logic blockset which inherently uses a lot of floating point variables. One method to overcome this draw back could be developing a fixed point version of the fuzzy logic blockset. Other parking strategies involving classical control could be experimented with Lego Mindstorms. Complex tasks like path planning could be executed on a computer communicating with the NXT via Bluetooth and the control tasks could be implemented on the NXT using fixed point math. However, with Model Based Design, being able to write programs in Simulink, simulate it and be able to execute this on the Lego Mindstorms opens a whole new dimension of what can be done ; limited only by our creativity! Bibliography C., Ho, C., Lin, S. Li, T. (2005). Omni-Directional Vision-Based Parallel-Parking Control Design for Car-Like Mobile Robot. Proceedings of the 2005 IEEE International Conference on Mechatronics, 562-567. De Luca, A., Oriolo, G., and Samson, C. 1998. Feedback control of a nonholonomic car-like robot. In Robot Motion Planning and Control, ed. J.-P. Laumond, 171-253. Berlin: Springer-Verlag Dongbing, G. and H. Huosheng (2000). Wavelet neural network based predictive control for mobile robots. Systems, Man, and Cybernetics, 2000 IEEE International Conference on. Galijasevic, A. M. a. Z. (2006). Model-Based Design Shortens Development Time of Motor Control Applications. Embedded Technology Journal. Guido Sandmann and Richard Thompson (2008). Development of AUTOSAR Software Components within Model-Based Design. The Math Works, Inc. Holve, R. Protzel, P. (1996). Reverse Parking of a Model Car with Fuzzy Control. 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Adaptation of Modern African-American Writers Essay -- Lucille Clifton

Adaptation of Modern African-American Writers Modern writers learn from the past by reading works written by authors of that particular era. Contemporary African-American writers gain knowledge and insight into the horrendous and sometimes harmonious conditions that plagued Africans during slavery and the slave trade. By reading the actual words, thoughts, and feelings of these enslaved Africans, modern writers receive information from the perspective of the victimized. Lucille Clifton's "slaveship" is a vivid example of a contemporary writer borrowing from the past to depict another account of the slave trade. The fact that Clifton's father told her stories about her family's struggle and she, herself, traced her lineage back to Dahomey, West Africa helped to impact the tone, ideas, and imagery used in her poem. Although "slaveship" is not written by someone who has experienced slavery herself, it does use similar elements found in Olaudah Equiano's Narrative of the Life of Olaudah Equiano and Phillis Wheatley's "On Being Broug ht from Africa to America". Clifton's "slaveship" begins with the image of people tightly packed and close together in the bottom of a ship. The narrator says that they were "loaded like spoons into the belly of Jesus" (lines 1-2). Later in the poem, the narrator describes being "chained to the heart of the Angel" (line 8). Equiano also speaks of the crowded conditions he faced on his journey to America. He states that he "was soon put down under the decks" (p 157) where "this wretched situation was again aggravated by the gallings of chains" (p 159). The human cargo on these slave ships endured weeks and months of dreadful and disgusting odors as a result of these cramped conditions. Clifton's slav... ...Equiano at the end of Chapter Two. He says, "O, ye nominal Christians might not an African ask you, learned this from your God, who says unto you, Do unto men as you would men should do unto you" (p 161). In order to give an accurate depiction of life during the Atlantic Slave Trade, contemporary African ‚American writers must research and read to find out exactly how life was for those enslaved. The opinions and thoughts of those who endured and survived this wretched time are valuable pieces of information about what was happening. Modern writers, such as Lucille Clifton, adapt from previous writers. Without having lived during that particular time, modern African-American writers must rely on past authors and their knowledge of human nature to put forth accurate stories with the purpose of educating and informing today's readers about America's ugly history.