harrison valetski

Valley Rafter A rafter that forms the intersection of an internal roof angle. The valley rafter is normally made of double 2-inch-thick members. Valley Flashing Sheet metal that lies in the "V" area of a roof valley. Valley The "V" shaped area of a roof where two sloping roofs meet. Water drains off the roof at the valleys. Trusses A framework of rafters, posts, and beams that forms the support for a roof. Tab The exposed portion of strip shingles defined by cutouts. Spire A tapering roof, or an ornamental metal piece on top of a tower or turret. Span The entire length of the roof from one side where the rafters are seated to the other side. Soffit The area under the roof extension often perforated to allow air flow assisting in the ventilation of an attic. Slate Roof A roof made of slate layers, tiles, or plates. Shed Roof A flat roof that slopes in one direction; often used on porch roofs or additions to houses. Saltbox Roof A roof that is shorter in th...

An underground container for storage of household wastewater; in the form of a concrete or metal tank, or a tank lined with logs, railroad ties, or concrete blocks. Cesspool Household water that comes from sinks, bathtubs, dishwashers, and washing machines; it does not contain human waste. Greywater A measure of heat transmission through a window or door. 'U' stands for unit. The lower the U-value, the greater the insulating capability. U-Value A colorless, odorless gas present in the environment as a result of radioactive decay in certain areas of the country. Homes should be tested for radon unsafe levels. The local environmental agency should be consulted on its handling, removal and any applicable laws. Radon A naturally occurring fibrous material sometimes found in older homes. It is a health hazard when a possibility exists of exposure to inhalable fibers. Asbestos A third-party rating system for energy efficiency. The USGBC (United States Green Building Council) con...

A durable siding material made of concrete fibers and other materials. Concrete or Cement Siding The arrangement of doors and windows in the facade of a building. Fenestration A block or brickwork on the corner of a building that is used for reinforcement or decorative use; usually constructed of different materials from the walls. Quoin A window that contains two panes of glass (upper and lower), as well as a screen. During warm weather, the extra panes of glass can be slid up and the screen slid down, allowing fresh air to get into the house. Triple Track Storm and Screen Combination A window where only the bottom part moves up and down and the upper part is fixed. Single Hung Window Holes deliberately made in brick veneer applications to carry moisture away from the building and to equalize air pressure. Weep Holes A window similar to an awning window, except it is often hinged at the bottom and opens into the building; commonly found in basements. Hopper Window A brand name ...

Review Questions Section 15.1 15.1 True or False? The Linux kernel and a Linux distribution are the same thing. False 15.2 What are the two types of Linux kernels? Developmental Kernel odd numbers Production Kernel even numbers 15.3 True or False? Linux is public domain software. False Section 15.2 15.4 What are the three main bodies of code in a Linux system? Kernel, system libraries, and system utilities Section 15.3 15.5 What is the benefit of using a kernel module? kernel modules allow a linux system to be set up with a standard minimal kernel without any extra device drivers built in Section 15.4 15.6 True or False? Linux uses a process model similar to UNIX systems. True 15.7 In addition to the fork() system call, what other system call can be used to create a thread in Linux? clone() Section 15.5 15.8 What are the two different types of scheduling algorithms in Linux?  Time-sharing algorithm and real-time priority based algorithm 15.9 What are passwords that al...

Review Questions Section 14.1 14.1 What is the most common technique for security attacks? masquerading 14.2 What are the four levels where security measures must be taken? physical, human, operating system, and network Section 14.2 14.3 Provide examplesof at least three program threats. trojan horse, trap door, logic bomb, stack and buffer overflow, and virus Section 14.3 14.4 Provide examples of at least two system and network threats. worms, port scanning and DDOS Section 14.4 14.5 True or False? Encryption requires possession of a key to read a message. True 14.6 What is the name of the encryption algorithm where the same key is used to encrypt and decrypt? Symmetric Encryption algorithm 14.7 What is the name of a commonly-used cryptographic protocol? SSL Section 14.5 14.8 What is the most common approach for authenticating a user? passwords 14.9 What are passwords that allow the space character are known as? passphrase Section 14.6 14.10 What is the first step of ...

Review Questions Section 13.1 13.1 True or False? Policies determine how something will be done,mechanisms describe what will be done. False Section 13.2 13.2 What principle dictates that programs and users be given just enough privileges to perform their tasks? Principle of Least Privelidge Section 13.3 13.3 True or False? The need-to-know principle states that a process needs to know everything in order to performits task. False the process should be limited to only those resources necessary to perform its task 13.4 True or False? The user mode/kernel mode paradigm is an example of domain switching. True 13.5 True or False? In the UNIX operating system, a domain is associated with a process, not with a specific user. False in unix a domain is associated with a user 13.6 What is the name of the bit in a UNIX system that associates each file with an owner and domain? setuid bit Section 13.4 13.7 What does each row and column representin an access matrix? each row represents a dom...

Review Questions Section 12.1 12.1 What are the two conflicting trends of I/O devices? Increased standardization of software and hardware interfaces, and an increasingly broad variety of I/O devices Section 12.2 12.2 What is a controller? A collection of electronics that can operate a port, a bus, or a device 12.3 True or False? Most CPUs allow some interrupts to be ignored so that a critical instruction cannot be interrupted. True Section 12.3 12.4 True or False?A given device may require different drivers for different operating systems. true 12.5 What is an alternative to a nonblocking system call? Asynchronous system call Section 12.4 12.6 List at least three different services provided by the kernel I/O subsystem. Scheduling, Buffering, Caching, Spooling, Device Reservation, and Error Handling Section 12.5 12.7 True or False? The lifecycle of an I/O request does not require many CPU cycles. False Section 12.6 12.8 What operating systemis the STREAMS mechanism designe...