12.07.2017
A STUDY GUIDE TO DC MOTOR CONTROLS

The persons who decide to take the present learning program and satisfactorily complete it, should be able to properly identify and subsequently explain to others the principles of operation of various types of the direct current motors, understand how a solid state direct current controllers regulate the motor speed, get duly familiarized with the very basic operating principles of a DC choppers and phase controlled rectifier bridges, understand and be able to correctly explain different ways of achieving the braking in a solid state direct current control systems, and to properly describe the conditions in such control systems that could possibly result in the operating problems.

Upon satisfactory completion of this module, the specialist must be able to recommend the procedures to avoid such problems, and implement them. The D/C motor controls consist of two parts, namely a motor itself, converting the electric energy into the mechanical motion, and a controller regulating the electrical energy that is required to operate the motors. The electrical power in this case will be regulated by means of the electronic components capable of producing the precise voltages in order to control the motor speed, it's force and torque, with the required level of accuracy...

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12.07.2017
A STUDY GUIDE TO AC INVERTERS

Another study guide from Tel-A-Train. This booklet starts with some basic info on the applications of the AC inverters, followed by the description of the AC induction motors. Then, the AC inverters are being explained, including the torque controllers, soft starter, and programmable controllers. This is all followed by the separate chapters that have been dedicated to the troubleshooting inverter - controlled systems, motors and loads, field devices and signals, the inverters and component testing.

Apart from the theoretical info, the booklet is full of practical exercises for better control of the understanding. The answers to all exercises are provided in the last chapter of the publication. All trainees who have managed to satisfactorily complete this program shall be able to name the three major components of the power section of an alternate current inverter and explain their function, understand how such inverters control the speed/torque of the induction motors, know the differences between a six-step inverter and a PWM inverter, be able to describe how to program the AC inverters to satisfy the requirements of specific application etc. Quite useful training tool for ship electricians...

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12.07.2017
A SHORT INTRODUCTION TO THEORETICAL MECHANICS

This perfect introductory publication that was specifically written and released to explain the very fundamentals of the classical theoretical mechanics. It starts with the chapter providing the very general overview of the theoretical mechanics, including the laws of motion, vectors and their equality together with all associated vector operations, position and velocity, acceleration, and relevant problems.

The second chapter of the volume is dedicated to the generalized systems of coordinates, including the definitions and theorems, as well as examples of such systems, basis vectors and metric tensor, numerous theorems and information related to the application to acceleration. The third chapter of the title is dealing with the differential equations, including their linear/non-linear solutions and numerical solutions. In the fourth chapter the author focuses on the one-dimensional motion, covering the associated definitions and theorems, while the following chapter concentrated on the particle motion in 2D and 3D.

In turn, the sixth chapter is covering the accelerated frames of reference, while the seventh chapter is dealing with the systems of interacting particles. The remaining chapters cover the rigid bodies and special theory of relativity. All theorems and other theoretical chapters are supplemented with several appendices...

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12.07.2017
A SHORT GUIDE TO CELESTIAL NAVIGATION

One may ask, why should celestial navigation be used in the age of electronics? However, it would look as if he or she asked why people keep developing classic black and white photographs in their darkrooms instead of utilizing high-color and high-definition digital cameras and associated software. The answer to both question would be - because it is more a noble art and it is fun.

Reading GPS displays is quite easy and not too exciting once you get used to it. But the celestial navigation is always a sort of challenge because all scenarios are different. Finding the geographical position of the vessel using the astronomical observations will always require proper knowledge and judgment as well as the ability to handle the delicate tools. In this case you will play a very active role in the whole process and this will require you to use all your skills.

It took many generations of astronomers and navigators, geographers and specialists in other relevant disciplines to get the celestial navigation developed to its today's state and the technical knowledge that has been collected in the course of this development, must not get forgotten. After all, everyone shall note that the celestial navigation remains a valuable alternative to the contemporary electronic navigation instruments should that fail for any reason.

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12.07.2017
A PRACTICAL ENGLISH GRAMMAR

This training material has been prepared and is intended for both intermediate and post-intermediate students of English. However, the authors of this publications hope that it will be equally useful for more advanced language learners. It is a thorough and comprehensive survey of structures and forms, written in very clear modern English; in addition, they have been illustrated with numerous examples.

Special attention has been given to difficult areas. Differences between grammatical forms and conversational usage are shown in the present book with the emphasis on conversational forms. You may read this book from the very beginning to the end or just go directly to the topics of your interest. It will also be ideal for all people learning English as a second language. We would say that it is a truly excellent exercise book for everyone, and maybe one of the best available today.

The publication is good for people willing to refresh their grammar skills. In fact,this title might easily serve as the main source of information for people studying English grammar, since the amount of the info provided in this book is enough to exclude the necessity of using any other supplemental publications. Try this one and you will see the result.

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12.07.2017
A NICE QUIET LIFE — THE LIFE OF A MERCHANT SEAMAN THROUGH TWO WORLD WARS

Alfred was born in Sunderland on 15" July 1884. He grew up living with his parents, and his younger brother William who was born three years later, in 1897. Their home was a modest terraced house in a fairly decent area of the town, and for his early education, he attended a "Penny-a-Week" School. Sunderland and Newcastle, at the time together formed the biggest ship building area in the world, and his father worked in the ship yards as a boiler inspector, checking the safety of boilers on the ships, and he was also a collector and dealer of machinery parts.

We don't know much more about Alfred's childhood except this tale of a summer holiday. When he was nine years old, he went by himself to visit his grandparents during his summer holidays. His grandfather John Learmond was head of the Customs in Cork, Ireland. Alfred was put on a train at Sunderland, under the care of the Guard, and transferred to the ferry to cross to Ireland, then took another train from Belfast to Cork. During this holiday he also travelled to Blarney Castle and kissed the famous Blarney Stone to give him good luck.

He certainly had that. After he left school, at the age of 14, he followed the family tradition and became an apprentice. He also became a choirboy in his local church, and later played the organ for the church services. Perhaps it was this experience that gave him a yearning to enter the church, because alter completing his apprenticeship he leit the world of engineering went on to a religious school - Kelham College, in Newark to study for the Priesthood. His fellow students and the lecturers at the College thought he was a very serious young man and not able to lighten up, so one day the students, as a prank, rolled him up in a corridor mat, which ended up outside the Principals door.

Alfred laughed so much the Principal came out of his office to see what was going on. He looked down at Alfred sternly, but then broke into a smile and said "Well Burlinson, I'm pleased to see you laughing at last". After that, he became accepted by the other students and life became more enjoyable, but the pressure of trying to master Greek and Latin was too much and sadly he was forced to give up this ambition. He returned to engineering, and using his apprenticeship qualifications he signed up with a merchant ship in 1908, as a junior engineer...

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12.07.2017
A SHIPYARD AT WAR - UNSEEN PHOTOGRAPHS FROM JOHN BROWNS, CLYDEBANK 1914-1918

The author of this world popular and famous publication, Ian Johnston, who is a professional graphic designer having a deep interest in ships and their construction, presents the perfect and rare collection of the selected stunning shipyard photographic images, most of which have never been published anywhere before. The Clydebank ship construction yard, although known mostly for capital vessels and large liners, did build a vast range of the vessels between 1914 and 1920.

This book includes two hundred images intended to depict in really unprecedented detail every single technical aspect of the shipyard's output, from Aquitania (1914) to Enterprise (1920). These images chronicle the huge impact that the war had on the working conditions in the ship yard, and especially in the introduction of women to the workforce. The publication is a remarkably vivid portrait of the lost industry at the very top point of its success.

The quality of the photos contained in the book is truly incredible and the descriptions are accurately detailed and very interesting to all categories of readers regardless of their background. The vast majority of the images are focusing on the construction of the fifty-four vessels that took place at the shipyard in the period 1914-1919...

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12.07.2017
A YEAR ON A PIRATE SHIP

This is an excellent story that will for sure be appreciated by the junior readers having the interest in the sea life and adventures, pirates and other symbols of the marine life. In fact, the authors have tried to make a story telling children what is taking place during a year spent on a pirate vessel. Each of the pictures supplementing the narrative text part of the book is showing the adventures of the pirates as the months of the ear are passing.

There are so many things happening, even so far out at the ocean, and the readers will be expected to spot them. Some of the pictures contained in the book have the fragments of the ships walls taken away, and such approach will help readers have a glance inside and see what is usually hidden from their eyes. There is a calendar provided at each of the right-hand pages of the volume telling the children which month they have already reached.

The book will for sure be highly appreciated by the junior readers; according to the reviews, people like the multicultural nature of the book; another major and important aspect is that women pirates have also be paid particular attention in the pages of the volume. The illustrations have been found great and vivid making the book a great choice.

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