College of Computer & Information Science Northeastern University Wireless Networks Lecture 2 Antennas and Propagation The notes in this document are based almost entirely on Chapter 5 of the textbook [Sta05]. Rappaport’s text is also a good reference for wireless signal propagation [Rap95]. 1 Antennas An antenna is an electrical conductor or a system of conductors that radiates/collects (transmits or receives) electromagnetic energy into/from space. An idealized isotropic antenna
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Software (program) consists of a series of related instructions‚ organized for a common purpose‚ that tells the computer what tasks to perform and how to perform them. • How does user interact with software? Two (2) Categories of Software • System Software o consists of the programs that control or maintain the operations of the computer and its devices. o serves as the interface between the user‚ the application software‚ and the computer’s hardware. o Two types of system software : Operating
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A human’s mind can be powerful‚ and sometimes the knowledge that comes from the mind can’t be controlled. “The map is not the territory” or in other words‚ the representation of the connection between nature or the reality it shows through knowledge‚ is linked to this question. Our mind is filled with knowledge that does need barriers at times and “mind maps” are things that are used to either simplify things or gain accuracy. Simplicity and accuracy are two things that can be mistaken for the other
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Computer Science Exam Classes‚ Objects‚ and Methods Attributes – data components of a class that provide and traits for the object of that class; also called fields‚ properties‚ and instance variables Methods – code associated with an object in order to make it function and behave according to the class to which it belongs: Constructor methods – to create or instantiate objects from the class definition A default constructor will always be created and will initialize fields to 0‚ false
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messages sent between computer processes. Here the entity types usually represent tables‚ and the relationship type lines represent the foreign keys between tables. The data model’s structure will often be tuned to the particular needs of the processes that operate on the data to ensure adequate performance. It will typically include: Restrictions on the data that can be held Denormalization to improve performance of specific queries Referential integrity rules to implement relationship types Rules
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1. What is code? (1.0 pts) Text that is written in a human-readable programming language that a computer can also interpret 2. What does the Python(command line) interpreter’s command prompt look like? (0.5 points) Like a standard command prompt. Black screen‚ white writing. 3. Name at least one way to deal with a frozen window. (0.5 points) Close the window and try again. 4. What does the reset() command do? (1.0 points) Erases everything drawn by the turtle and moves the turtle back
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important part of life for many people. Even people who are not all that religious by nature consider it to be important. The rise of science during the renaissance in Europe created a confrontation between religion‚ science and philosophy which still persists today. Is religion still useful to civilization? In this paper an evaluation of the conflict between religion and science will be discussed. Dictionary.com defines religion as‚ “a set of beliefs concerning the cause‚ nature‚ and purpose of the universe
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corresponding development in the concept of responsibility as it applies to computing practitioners" (107). Gotterbarn believes that computer professionals should be perfect and are responsible for any effects caused by their coding. I disagree with Gotterbarn on this matter. In this essay‚ I will show that Gotterbarn’s thoughts and beliefs on professional responsibility in computer ethics are unreasonable and therefore should not be applied. Gotterbarn begins his article with examples of problems that resulted
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Computer Science is basically concerned with the study of computers. A student of Computer Science learns about hardware and operating systems. It is also about highly technical stuff like registers‚ multitasking kernels‚ databases and address buses. It is said to be about the principles of computing and about the design of the computer and its operation. Computer science is concerned only with computers while it is not so with Information technology. Information Technology on the other hand
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providing congratulations or a helping hand when necessary. Such interpersonal relationships bring both social and health benefits. Problems can arise‚ however‚ when these individuals are coworkers or underlings. Although my friends and I are involved in many of the same clubs‚ relationships have rarely been muddled. Until this year‚ I never encountered much conflict over seemingly small concerns. As president of Science Olympiad‚ I organize the club’s representation in different events. This ranges
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