Thursday, October 31, 2019

Analysis Paper Essay Example | Topics and Well Written Essays - 750 words

Analysis Paper - Essay Example Moreover, he has even-keel temperament and has ability for consensus-building. He's also a talented, introspective writer. However, Barrack Obama is more discussed from political and presidential point of view. This research paper discusses different forums where people have given their true opinions or reflections about Mr. Barack Obama. Reflections on Barack Obama The people opinions or reflections from online blogs, social networking websites, newspapers and articles are summarized as follows Online Blogs In an online blog, answering a question an individual stated that Barak Obama is the best president up till now the US has elected (Scifiman, 2007). Another user commented that he is a very courageous man who is continuously trying his best to satisfy the needs of the country. Moreover, his promise to make Washington work more transparent is appreciated. People have remarked him as hard worker who hasn’t turned his back on anyone. Some people appreciate the work of Mr. Oba ma commenting that all countries must have a president like him to make world a safer and gentle planet (Newbie, 2007). People have wished him success in all upcoming years and want him back again as president of US. Moreover, people believe that he is the one who will keep promise to strengthen US nation and will improve the lives of American nation (Troxler, 2008). Cammillie (n.d.) says that President Obama is better than the rest of the people and therefore he should be re-elected. Sarcastically, some people view him as best teleprompter reading (Sheltan, 2007). Although, he did well very little; but his speeches are heard by many. Moreover, Orson Scott Card (2008) comments that Obama's limited attitude about global warming and energy will add cost burden on America's poor people. Obama’s views on war are disagreed by most of the people. Deborah (n.d.) says that US must now stop invading other as the burden is shifted towards American taxpayer. Paying taxes kills American people. Moreover, people are against war which has resulted in sowing many social evil factors within American society such as drug abuse, disability, depression etc. People are more of view to have peaceful life. Rossmarie (n.d.) says that Obama is deceiving US nation by pretending that he is a transparent, moderate and unifying candidate. Moreover, he is destroying US military. Bobbie (n.d.) comments that Barrack Obama is a cold-hearted US hater who is somewhat responsible for the high debt that the country is facing in its history. Social Networking Websites Barack Obama is being discussed on Social media websites as well such as face book and twitter. Many face book pages are created on Barack Obama were people writes their comments, add videos, images etc. A quick survey of face book page shows that more people like him as their leader and have positive reviews regarding his presidency. The only thing that people discourages about his leadership is the increased tax burdens and war killings. However, besides appreciating US president, some people are against him and do not like his leadership. Slogans such as Go-Obama and No-Obama were observed my few individuals (Barrack Obama (b), 2012.). Similarly, social networking users have tweeted Barack Obama’s page on Twitter where the people’s opinion and discussions are same as that in face book (Barrack Obama News, 2012). Newspapers and articles New York Times has encouraged Obama as his victory is evidenced as he took

Tuesday, October 29, 2019

The increase or decrease in CO2 emission Essay Example for Free

The increase or decrease in CO2 emission Essay Purpose The purpose of this report is to determine the increase or decrease in CO2 emission over the past 40 years. Showing that human activity is the reason for the altering of the CO2 emissions to the earth. Resulting in the unbalancing of ecosystems across the globe. (M.U.S.E., 2010) Introduction Carbon dioxide is naturally present in the atmosphere as part of the Earths carbon cycle. Yet human-related emissions are responsible for the increase in CO2 emissions. The use of electricity accounts for 37% of total U. S. emissions, while transportation 31%, industry accounts for 15%, residential and commercial 10%, and other non-fossil fuel combustion 6%. That is 99% of the total globe greenhouse gas emissions. Carbon dioxide (CO2) emissions in the United States increased by about 7% between 1990 and 2013. (EPA, 2015) Not leaving out pollution also a contributor of increases in anthropogenic CO2. These things are the cause of the earth heating up, or global warming. Trees and plants help soak up the CO2 in the atmosphere but with the tearing down of trees to build industry buildings, residential and commercial buildings there are fewer trees and plants to take in CO2 for photosynthesis. Hypothesis and Predicted Outcomes If humans could find other resources that do not involve the combustion of fossil fuels, maybe there could be a chance to slow down the increasing CO2 emissions, if not the globe will continues to heat becoming more and more hazardous to humans, animals and plants on this planet. Methods For this lab I utilized information taken from the M.U.S.E as well as  information gleaned from the Environmental Protection Agency (EPA). Discussion and Analysis Looking at the above chart it seems that within the 15 years from 1990 to 2014 there has been a big jump, but thinking about the last 40 years there has been a greater increase. As each generation of new industry products have come on the scene as well as more residential and commercial projects that have been generated, we tend to continue to add to the CO2  emissions problem. The auto industry is endeavoring on becoming more energy conscious by developing hydro vehicles. Like the auto industry it would be a good thing if more companies and families become more conscious of what is happening to our world. This can only happen through education and programs to stop global warming. References Career Education Corporation, (2015). Lab 3: Earth System Research Laboratory: Global Monitoring Division. Retrieved June 7, 2015 from M.U.S.E. https://campus.ctuonline.edu/courses/SCI1203/p1/hub1/hub.html EPA. (2015). Overview of Greenhouse Gases Carbon Dioxide Emissions. Retrieved June 7, 2015 from http://www.epa.gov/climatechange/ghgemissions/gases/co2.html

Sunday, October 27, 2019

Building Management System to Save Energy

Building Management System to Save Energy 1. Introduction of BMS Building Management System (BMS) is to control and monitor building services systems in an efficient way by centralizing the control of individual systems ( 1.1). The systems include HVAC, Fire Services Lift, Escalator, Lighting, Electrical Distribution, Steam Hot Water, and Plumbing Drainage. The main function of BMS is centralized control monitoring and fault management. So it has another name call Central Control and Monitoring System (CCMS). The other functions are enhance interface connectivity between systems, service response to customer, operator control of systems and graphical display to make the control of system more users friendly. Improve energy efficiency and operational efficiency. Allow capacity for future upgrades expansions and automation. And related system Building Automation System (BAS) will be use on BMS. 2. Basic BMS Design 3-Levels BMS Architecture ( 2.1): l Management Level User can configure and monitor plant performance. Anticipate future trends, improve efficiency, and analyze management report. l Automation / Controller Level The location with greatest technical control requirement, and differentiate one from others. Controllers automatically perform their tasks from I/P and to O/P. Controllers can communicate with each other (Peer-to-Peer). Event based operation. The devices can function at the highest efficiency and no repetitive information is transmitted. Controllers only react with the Management Level when plant goes out of limits, and adjustments are made through a user interface. l Field / Floor Level Information is gathered through sensors and other intelligent devices. The information will be sent back to the controllers. Third party equipment is integrated into the Automation and Field levels with control at the Management level. Centralized Architecture: Centrally controlled system ( 2.5) A control system in which transmission is to a central computer and the reliance of all controls on a central computer. Distributed Architecture: Distributed control ( 2.6) A control system in which control computations and intelligence are made at different locations and the result coordinated. System Architecture: The constraints of BMS are network expansion, the limited variety of topologies and transmission media. The solutions are mixing of communication media (twisted pair, power line, radio, infra-red, fibre optics, coaxial). Complete implementation of OSI model. Using free topology, user-friendly software and development cost. System Topology Topology affects system redundancy, communication protocol and system response time. The common system topologies such as: Bus, Star, Tree, Ring and Mesh. Bus Topology ( 2.7) All devices are connected to a central cable, call the bus or backbone. The advantage is much less cabling requirements. The brands using include Ethernet, Profitbus, ControlNet, LonWorks. Star Topology ( 2.8) All devices are conned to a central hub. Star networks are relatively easy to install and manage, but bottlenecks can occur because all data must pass through the hub. Cable fault affects one device only. But communication hub fault affects all devices. The brands using include Ethernet, Profitbus, ControlNet, LonWorks. Tree Topology ( 2.9) The topology combines characteristics of linear bus and star topologies. It consists of groups of star-configured workstations connected to a linear bus backbone cable. Tree topologies allow for the expansion of an existing network, and enable schools to configure a network to meet their needs. Device at the highest point in the hierarchy controls the network. The brands using include Ethernet, Profitbus, ControlNet, LonWorks. Ring Topology ( 2.10) All devices are connected to one another in the shape of a closed loop, so that each device is connected directly to two other devices, one on either side of it. Same as bus network with both edges connect. The brands using include Token Ring, FDDI, Profitbus. Mesh Topology (Fig 2.11) Network topology which combines more than one basic topology such as bus, ring, or star. Good for redundancy. It will use lots of cable to connect every device with every device. Considerations in Topology Layout for automating building with vast amount of points require well-designed network segmentation, in order to achieve a good performance infrastructure. Well designed structured network by using repeaters, bridges or even better using routers to improve network reliability and simplify network troubleshooting. Some reasons why segmenting a network is important: Isolation of individual network segments in order to limit the propagation of a single fault to one segment and prevent this single fault from spreading out over the entire network. Different nodes demand different communication media and different network speeds but they all need to communicate with each other, which requires and interconnection between the different networking media. Increase the number of possible nodes in a single network and increase the number of possible nodes in a single network. Keep local traffic within one segment in order to avoid network traffic overload conditions which will make service like HVAC, lighting malfunction. BMS Configurations There are three types configurations using in BMS: 1. Conventional configuration Server workstations daisy chained with DDCs (usually using RS-485). Typical RS-485 Controller Level network ( 2.14) relatively low bandwidth (around 9600 bps). The limited nodes around 100, and the distance is lower than 1200m. Only for data transmission. Controller Level Network 2. Ethernet-Based configuration Use Ethernet as transmission media. Servers, Workstations and DDCs on the same Ethernet platform. Typical Ethernet-Based Network ( 2.15) with high bandwidth (typical 1Gbps backbone). Use IP Technology means open platform for various applications. Virtually no distance limitation. Always use for data, voice video systems. Ethernet-Based Network 3. Hybrid configuration ( 2.16) Non-hierarchy architecture with combination of different independent networks and interfaces. Various network topologies. Hybrid Configuration Networking Protocol Protocol ( 2.17) is a set of rules, which allows computer/controllers/devices to communicate from one to another. Proprietary Protocols developed by systems or computer manufacture to communicate to their OWN hardware and software over a recommended network. Open Protocols opening up protocols means disclosing procedures, structures, and codes and allowing other system developers to write interfaces and share data on their network. Acceptance of an open protocol depends on its quality, features, and services provided. 2.17 Protocol The OSI Seven Layer Model ( 2.18) Each layer has a defined set of functions. The model provides a useful common reference to communicate protocol. Most communication protocols including those used in our field today use either all or some of the seven layers of the OSI model. 1. Network-capable Applications produce DATA. 2. Each protocol layer adds a header to the data it receives from the layer above it. This is called encapsulation. Encapsulated data is transmitted in Protocol Data Units (PDUs). There are Presentation PDUs, Session PDUs, Transport PDUs etc. 3. PDUs are passed down through the stack of layers (called the stack for short) until they can be transmitted over the Physical layer. 4. Any layer on one machine speaks the same language as the same layer on any other machine, and therefore can communicate via the Physical layer. 5. Data passed upwards is unencapsulated before being passed farther up. 6. All information is passed down through all layers until it reaches the Physical layer. 7. The Physical layer chops up the PDUs and transmits the PDUs over the wire. The Physical layer provides the real physical connectivity between machines over which all communication occurs. 2.18 OSI Seven Layer Model The Physical layer provides for physical connectivity between networked devices. Transmission and receipt of data from the physical medium is managed at this layer. The Physical layer receives data from the Data Link Layer, and transmits it to the wire. The Physical layer controls frequency, amplitude, phase and modulation of the signal used for transmitting data, and performs demodulation and decoding upon receipt. Note that for two devices to communicate, they must be connected to the same type of physical medium (wiring). Ether to Ether, FDDI to FDDI etc. Two end stations using different protocols can only communicate through a multi-protocol bridge or a router. The physical layer is responsible for two jobs: 1. Communication with the Data link layer. 2. Transmission and receipt of data. The Datalink Layer is the second layer of the OSI model. The datalink layer performs various functions depending upon the hardware protocol used, but has four primary functions: 1. COMMUNICATION with the Network layer above. 2. SEGMENTATION of upper layer datagrams (also called packets) into frames in sizes that can be handled by the communications hardware. 3. BIT ORDERING. Organizing the pattern of data bits before transmission (packet formatting) 4. COMMUNICATION with the Physical layer below. This layer provides reliable transit of data across a physical link. The datalink layer is concerned with physical addressing, network topology, physical link management, error notification, ordered delivery of frames, and flow control. Network Layer establishes and terminates connections between the originator and recipient of information over the network. Assign unique addresses to each node on the network. The addresses identify the beginning and end of the data transmission packets. Outbound data is passed down from the Transport layer, is encapsulated in the Network layers protocol and then sent to the Datalink layer for segmentation and transmission. Inbound data is de-fragmented in the correct order, the IP headers are removed and then the assembled datagram is passed to the Transport layer. The Network layer is concerned with the following primary functions: 1. Communication with the Transport layer above. 2. Management of connectivity and routing between hosts or networks. 3. Communication with the Datalink layer below. Transport Layer maintain reliability on the network and enhances data integrity by delivering error-free data in the proper sequence. It may use a variety of techniques such as a Cyclic Redundancy Check, windowing and acknowledgements. If data is lost or damaged it is the Transport layers responsibility to recover from that error. Functions: 1. Communicate with the Session layer above. 2. Detect errors and lost data, retransmit data, reassemble datagrams into datastreams 3. Communicate with the Network layer below. The session layer tracks connections, also called sessions. For example: keep track of multiple file downloads requested by a particular FTP application, or multiple telnet connections from a single terminal client, or web page retrievals from a Web server. In the World of TCP/IP this is handled by application software addressing a connection to a remote machine and using a different local port number for each connection. The session performs the following functions: 1. Communication with the Presentation layer above. 2. Organize and manage one or more connections per application, between hosts. 3. Communication with the Transport layer below. The Presentation layer handles the conversion of data formats so that machines can present data created on other systems. For example: handle the conversion of data in JPG/JPEG format to Sun Raster format so that a Sun machine can display a JPG/JPEG image. The Presentation layer performs the following functions: 1. Communication with the Application layer above. 2. Translation of standard data formats to formats understood by the local machine. 3. Communication with the Session layer below. The application layer is the application in use by the user. For example: a web browser, an FTP, IRC, Telnet client other TCP/IP based application like the network version of Doom, Quake, or Unreal. The Application layer provides the user interface, and is responsible for displaying data and images to the user in a recognizable format. The application layers job is to organize and display data in a human compatible format, and to interface with the Presentation layer. Message Frame Format Fig 2.19 Message Frame Format Master-Slave Protocol (2.20) The control station is called master device. Only master device can control the communication. It may transmit messages without a remote request. No slave device can communicate directly with another slave device. 2.20 Master-Slave Protocol Peer-to-Peer Protocol (2.21) All workstations are loaded with the same peer-to-peer network operating system. Each workstation configured as service requester (client), service provide (server), or even BOTH. 2.21 Peer-to-Peer Protocol Client-Server Protocol (2.22) Client workstation are loaded with specialized client software. Server computers are loaded with specialized server software designed to be compatible with client software. 2.22 Client-Server Protocol The CSMA/CE Protocol is designed to provide fair access to the shared channel so that all stations get a chance to use the network. After every packet transmission all stations use the CSMA/CD protocol to determine which station gets to use the Ethernet channel next. CSMA/CD likes a dinner party in a dark room: Everyone around the table must listen for a period of quiet before speaking (Carrier Sense). Once a space occurs everyone has an equal chance to say something (Multiple Access). If two people start talking at the same instant they detect that fact, and quit speaking (Collision Detection). IEEE 802.3 standard covers CSMA/CD. Switched Ethernet nodes are connected to a switch using point-to-point connections, When a frame arrives at the switch, the control logic determines the transmit port. If the transmit port is busy, the received frame is stored in the queue which is a First-in First-out (FIFO) queue. The memory to store pending frames is obtained from a shared memory pool. In case the memory is full, the received frame is dropped. Networking Cables Copper wire pairs are the most basic of the data media. †¢ Two wire untwisted pair The insulated wire conductors run in parallel, often in a moulded, flat cable. Normally used over short distances or at low bit rates, due to problems with crosstalk and spurious noise pickup. Performance in multiple conductor cables is enhanced by dedicating every second cable as a ground (zero volt reference), and by the use of electrically banetworkced signals. 1. A single wire is used for the signal transmission/reception 2. A common reference level/point is existed between the transmitter and receiver 3. It is the simplest connection technique but it is sensitive to noise, interference, loss, and signal reflection 4. It is suitable for short distance and low data rate application (Normally less than 200Kb-meter/s) †¢ Twisted Pair The insulated conductors are twisted together, leading to better electrical performance and significantly higher bit rates than untwisted pairs. UTP is unshielded, like telephone cable, whilst STP is shielded and capable of higher bit rates. Systems using banetworkced signals obtain the highest bit rates. 1. Twisting or wrapping the two wires around each other reduces induction of outside interference 2. 1 to 5 twists per inch is quite typical †¢ Cheap and moderate bit rate applications 3. For a few km distance the bit rate can be up to 10Mb/s, and 100Mb/s can be achievable for short distance applications like 100m 2.23 Two wire untwisted pair and Twisted Pair Unshielded Twisted Pair (UTP): †¢Composed of two of more pairs of wires twisted together †¢Not shielded †¢Signal protected by twisting of wires †¢Impedance of 100W †¢Recommended conductor size of 24 AWG 2.24 Unshielded Twisted Pair Cat5e: 100MHz ANSI/TIA/EIA-568-B.1 Cat6: 250MHz Cat7: 600MHz Undercarpet: †¢Susceptibility to damage †¢Limited flexibility for MACs (move, add and change) †¢Distance limit of 10m †¢Avoid in high traffic areas, heavy furniture locations, cross undercarpet power on top at 90 degrees 2.25 Cat3, Cat5e and Cat6 Cable Screened Twisted-Pair (ScTP): †¢Characteristic impedance of 100 W †¢Four pair 22-24 AWG solid conductors †¢Mylar/aluminum sheath around all conductors †¢Drain wire that must be grounded 2.26 Screened Twisted-Pair Shielded Twisted Pair (STP): †¢Composed of two pairs of wires †¢Metal braid or sheathing that reduce electromagnetic interference (EMI) †¢Must be grounded †¢Characteristic impedance of 150 W †¢Conductor size is 22 AWG †¢Electrical performance is better than UTP (300MHz bandwidth) †¢More expensive †¢Harder to handle thick and heavy 2.27 Shielded Twisted Pair Coaxial Cable (Coax): Composed of insulated center conductor with braided shied. It provides high degree of protection against EMI. †¢Because the electrical field associated with conduction is entirely carried inside the cable; problems with signal radiation are minimized very little energy escapes, even at high frequency. †¢There is little noise pick up from external sources. Thus, higher bit rates can be used over longer distances than with twisted pairs 2.28 Coaxial Cable Series 6 (Video): †¢Characteristic impedance of 75 ohms †¢Mylar/aluminum sheath over the dielectric †¢Braided shield over the mylar †¢18 AGW solid-center conductor 2.29 Series 6 Series 11U (Video): †¢Characteristic impedance of 75ohms †¢Mylar/aluminum sheath over the dielectric †¢Braided shield over the mylar †¢14 AWG solid-center conductor or 18 AWG stranded-center conductor 2.30 Series 11U Series 8: †¢50 ohms characteristic impedance †¢Multiple mylar/aluminum sheath over the dielectric †¢Multiple braided shield over the mylar †¢11 AWG solid-center conductor 2.31 Series 8 Series 58 A/U: †¢50 ohms characteristic impedance †¢Mylar/aluminum sheath over the dielectric †¢Braided shield over the mylar †¢20 AWG solid-center conductor 2.32 Series 58 A/U Fibre Optics: Higher bandwidth and much lower signal loss than copper conductors. It used in the backbone or in horizontal runs of huge control network. †¢The data is carried as pulses of light from a laser or high-power LED. †¢Optical fibre is non-electrical, hence is completely immune from electrical radiation and interference problems. It has the highest bit rate of all media. †¢The fibre consists of an inner glass filament, contained inside a glass cladding of lower refractive index, with an outer protective coating. In a step index fibre, there is a sudden transition in refractive index. A graded index fibre has a gradual transition from high to low index, and much higher performance. †¢Most common fibres are multimode, where the inner fibre is larger than the wavelength of the light signal, allowing multiple paths to exist, and some dispersion to limit the obtainable bit rate. In single mode fibres, the inner fibre is very thin, and extremely high bit rates (several Gbps) can be achieved over long distances. 2.33 Fibre Optics Multimode Fibre: Composed of a 50 or 62.5 micron core and 125 micron cladding. It commonly used in horizontal and intrabuilding backbones. It has distance limitation of 2000m. Often uses a light-emitting diode (LED) light source. †¢The center core is much larger and allows more light to enter the fiber †¢Since there are many paths that a light ray may follow as it propagates down the fiber, large time dispersion may occur which results in short distance applications or bandwidth reduction †¢Because of the large central core, it is easy to couple light into and out of the this type of fiber †¢It is inexpensive and simple to manufacture †¢Typical value: 62.5/125 Multi-Mode Graded Index †¢It is characterized by a center core that has non-uniform refractive index †¢The refractive index is maximum at the center and decreases gradually towards the outer edge †¢The performance is a compromise between single-mode step index fiber and multi-mode step index fiber 2.34 Multi-Mode Fibre Singlemode Fibre: It composed of a 6 or 9 micron core and 125 micron cladding (say8/125 or 9/125). It used for distances up to 3000m. It uses a laser light source. †¢Small core diameter so that there is essentially only one path that light may Take care,as it propagates down the fiber †¢ There is minimum time dispersion because all rays propagating down the fiber with the same delay time and results in wider bandwidth (i.e. high bit rate) †¢ Because of the small central core, it is difficult to couple light into and out of the this type of fiber †¢ It is expensive and difficult to manufacture †¢ Typical value: 9/125 2.35 Singlemode Fibre 2.36 LAN Media Technology Analysis Open System The definition of open system is that system implements sufficient open standards for interfaces and services. It is supporting formats to enable properly engineered components to be utilized across a wide range of systems and to interoperate with other components. And that system in which products and services can be mixed and matched from set of suppliers; and supports free exchange of information/data between different systems without inserting gateways or proprietary tools. Some benefits from Interoperability: †¢Devices can be shared among different subsystems. †¢Reduce cost, shorten installation time, and reduce complexity as parts are being reduced. †¢Devices in different subsystems can interact with each other; therefore, new breed of applications can be created easily. †¢Owners can choose the best-of-breed products from different manufacture. †¢Elimination of gateway dependency, especially during system upgrade. †¢Allow move-add-change relatively easy, hence lower life-cycle costs. The characteristics of open system are well defined, widely used, preferably nonproprietary interfaces/protocols; Use of standards which are developed/adopted by recognized standards bodies or the commercial market place; and definition of all aspects of system interfaces to facilitate new or additional systems capabilities for a wide range of applications. The different between proprietary protocols and open protocols; For Proprietary protocols, most manufactures have their own proprietary protocols within their systems, so no communication between Systems unless a gateway is deployed. For open protocols, it allows systems of different manufacturers to communicate. Systems communicate with each other. 2.1 BMS Open System Modbus: A high-level protocol for industrial networks developed in 1979 by Modicon (now Schneider Automation Inc.) for use with its PLCs. It is providing services at layer 7 of the OSI model. Modbus defines a request/response message structure for a client/server environment. It is the most commonly available means of connecting industrial electronic devices. Several common types of Modbus: l Modbus RTU n A compact, binary representation of the data. l Modbus ASSII n Human readable more verbose. l Modbus/TCP n Very similar to Modbus RTU but is transmitted within TCP/IP data packets. 2.37 Modbus 2.2 BMS Open System ARCent: Attached Resource Computer NETwork (ARCnet) was founded by the Data point Corporation in late 1970s. ARCnet was one of the topologies used early on networking and is rarely used as the topology of choice in current LAN environments. ARCnet, however, still is a solid, functional and cost effective means of networking. Each device on an ARCnet network is assigned a node number. This number must be unique on each network and in the range of 1 to 255. ARCnet manages network access with a token passing bus mechanism. The token (permission to speak on the network) is passed from the lowest number node to higher number nodes in ascending order. Lower numbered addresses get the token before the higher numbered addresses. Network traffic is made more efficient by assigning sequential numbers to nodes using the same order in which they are cabled. Choosing random numbers can create a situation in which a node numbered 23 can be a whole building away from the next number, 46, but in the same ro om as numbers 112 and 142. The token has to travel in a haphazard manner that is less effective than if you numbered the three workstations in the same office sequentially, 46, 47, and 48, and the workstation in the other building 112. With this configuration, the packet stays within the office before venturing on to other stations. A maximum time limit of 31 microseconds is allotted for an ARCnet signal. This is also called a time-out setting. Signals on an ARCnet can travel up to 20,000 feet during the 31-microsecond default time-out period. You can sometimes extend the range of an ARCnet by increasing the time out value. However, 20,000 feet is the distance at which ARCnet signals begin to seriously degrade. Extending the network beyond that distance can result in unreliable or failed communication. Therefore, the time-out parameter and cabling distance recommendations should be increased only with great caution. An ARCnet network is used primarily with either coax or twisted pair cable. Most older ARCnet installations are coax and use RG-62 A/U type cable terminated with 93 Ohm terminators. Twisted pair (UTP) installations are newer and use stranded 24 or 26 gauge wire, or solid core 22, 24, or 26 gauge type cable terminated with 100-Ohm terminators. Many ARCnet networks use a mix of both coax and UTP cabling. UTP cable is simple to install and provides a reliable connection to the devices, whereas coax provides a means to span longer distances. Typical ARCnet installations are wired as a star. ARCnet can run off a linear bus topology using coax or twisted pair as long as the cards specifically support BUS. The most popular star-wired installations of ARCnet run off two types of hubs: 1. Passive hubs cannot amplify signals. Each hub has four connectors. Because of the characteristics of passive hubs, unused ports must be equipped with a terminator, a connector containing a resistor that matches the ARCnet cabling characteristics. A port on a passive hub can only connect to an active device (an active hub or an ARCnet device). Passive hubs can never be connecte

Friday, October 25, 2019

An Ethical Evaluation of Peer-to-Peer File Swapping Essays -- File Sha

An Ethical Evaluation of Peer-to-Peer File Swapping Abstract The last few years has seen an explosion in the use of the Internet as a means for exchanging, free of charge, digital media by way of Peer-to-Peer (P2P) file sharing technologies. Initially, the practice was primarily limited to the swapping of music, in the form of MP3 files. The pervasiveness of broadband, the advent of newer file types, and the creation of more sophisticated technologies has subsequently made possible the exchange of other types as well – including movies, television shows and software. Again, for free. In this paper, we will explore the ethical considerations of this practice as it relates to Intellectual Property (IP) – whether protected by copyright law or not. We will concentrate primarily on music, but where appropriate, other media will be considered, as many of the issues are common across the different types. Taking a global perspective, one must keep in mind that the term â€Å"copyright† is not universally defined, accepted, or enforced. We must therefore use the term with the United State’s definition as a basis. However, absent U.S. law, we must also consider the creator’s intent as it relates to the distribution and use of his or her work. This exploration will lead us to a universal position – one that claims that the wide-scale, free exchange of Intellectual Property by means of P2P technology is unethical. The Technology The P2P model gained wide scale notoriety with the success of Napster in late 1999. Almost overnight, P2P and Napster became household words. There are essentially two variations of the P2P model – the Napster model and the Gnutella model. Both follow the fundamental principle of P2P sharing ... ... Article also available on the web at: http://www.time.com/time/magazine/article/0,9171,1101030505-447204,00.html [10] Preston Carter – engineer at Hewlett-Packard – and a very insightful friend. References In addition to references cited above: Nolo Press, Nolo Law For All, Copyright Ownership: Who Owns What? http://nolo.com/lawcenter/ency/article.cfm/objectid/BABFA71E-97C9-479F-8A9D4C3DB2498663/catID/2EB060FE-5A4B-4D81-883B0E540CC4CB1E Nolo Press, Nolo Law For All, Copyrighting Your Software – Why Bother? http://nolo.com/lawcenter/ency/article.cfm/objectID/B09BB4E7-5744-4131-8B29ACD7CC408853/catID/2EB060FE-5A4B-4D81-883B0E540CC4CB1E Nolo Press, Nolo Law For All, Copyright Protection: What It Is, How It Works http://nolo.com/lawcenter/ency/article.cfm/objectid/6A6540E0-325F-4BBE-A9B64DB3BB7BAAF0/catID/2EB060FE-5A4B-4D81-883B0E540CC4CB1E

Thursday, October 24, 2019

How has IT affected Society? Essay

The term information technology (IT) refers to anything related to computing technology, such as networking, hardware, software, the Internet, or the people that work with these technologies. IT evolved in the 1970’s and has become a part of our everyday lives. †¢Globalization: The creation of one interdependent system helps us to share information and end linguistic barriers across the continents. The technology has not only made communication cheaper, but also possible much quicker and round the clock. The wonders of text messages, email and auto-response, backed by computer security applications, has opened up scope for direct communication. †¢Creation of New Jobs: Things that were once done manually or by hand have now become easier and faster due to the advent of a computing technology. A whole new field of opportunities for skilled persons has opened up such as web designers, computer programmers, system analyst etc. †¢Cost effective: Information technology has helped to computerize the business process to make them extremely cost effective money making machines. This in turn increases productivity which ultimately gives rise to profits that means better pay and less strenuous working conditions. †¢Privacy: Though information technology may have made communication quicker, easier and more convenient, it has also bought along privacy issues. From cell phone signal interceptions to email hacking, people are now worried about their once private information becoming public knowledge. †¢Dominant culture: While information technology may have made the world a global village, it has also contributed to one culture dominating another weaker one †¢Loss of personal touch: emails and instant messaging have replaced the old tradition of handwriting letters. †¢Theft of personal information †¢Pornography †¢Unemployment †¢Lac of job security IT use in Mexico has changed since the implementation of NAFTA. Specifically, it appears that the indirect effects of NAFTA have increased investment and foreign firm activity in Mexico, which has ultimately increased IT use. However, the uniform proliferation of IT throughout Mexico, especially among domestic firms and within the more rural areas, appears to be weak. NAFTA, though helpful, could have been more effective in stimulating IT adoption if it were aided by further government interventions and if more focus was directed at building up a more conducive IT infrastructure. Cuba is the Caribbean’s largest and least commercialized island and one of the world’s last bastions of communism. The island’s relative political isolation has prevented it from being overrun by tourists, and locals are sincerely friendly to those who do visit. Cuba’s international telecommunication infrastructure is in better condition and better able to meet current and future demand than their internal infrastructure, although that is also improving. Demand for telecommunication is rising in spite of the economic effects of the loss of Eastern Europe and the embargo. Key industries which generate hard currency (tourism and biotechnology) require communication, and their requirements are being slowly funded. And article covering the effect of technology on the society of Nigeria While students may hunger and yearn for computers they do not have the earning power to buy PC â€Å"While students may hunger and yearn for computers they do not have the earning power – so while the demand will be catalyzed by students it will be actualized by willing parents, wards, guardians, mentors and other well meaning Nigerians who are willing to invest as little as N3, 500 a month in the future of the country†, Omobola Johnson, Minister of Communication Technology says summing up the launch of the Student PC Ownership Programme to equip Nigerian students with computers. Cost effectiveness on Businesses Quicker Communication Theft of personal information The Information Technology Society deals with all aspects of information technology in industry, administration, teaching, research and science. Its primary aim is to promote the scientific and technical development of information technology and its practical application. The ongoing computing and communications revolution has numerous economic and social impacts on modern society and requires serious social science investigation in order to manage its risks and dangers. Each technology has its users and developers. They determine the importance and influence of technology on the consumer. To determine and group the users and developers of the information technology, special properties have to be taken into account.

Tuesday, October 22, 2019

Village Of Skokie Vs. The Aclu Essays - Skokie Controversy

Village Of Skokie Vs. The Aclu Essays - Skokie Controversy Village Of Skokie Vs. The Aclu Skokie In the case of Village of Skokie vs. The ACLU(American Civil Liberties Union) I would definitely stand with the ACLU. The ACLU was defending the First Amendment Right. They were not defending the Nazis. We might not agree with what the Nazis are saying but, they still have a right to say it. Herb Lewison of the ACLU and the attorney for Collin stated to the judge Your Honor, this is a simple First Amendment case. The Village of Skokie seeks and order, preventing the exercise of free speech before the speech has even occurred, in spite of the fact that it has been proposed as an orderly exercise, taking place for only 20 minutes on public property in front of the Skokie Municipal Building. This section of the quote from Herb Lewison is simply saying that Skokie is just trying take away the first amendment right of the Nazis. Everything that they are asking for falls within their first amendment right. All they are just proposing is an orderly march. An orderly march for 20 minutes on public property. This is okay in my opinion because everything is offensive to someone. But you still have the right to voice your opinion. The second quote Lewison states is, This is a classic case in which government officials are asking a court of equity to impose a prior restraint on the speech of persons advocating unpopular ideas. Lewison is saying in this part of his summary argument that the government is asking the court to issue a prior restraint on the speech because they dont agree with their ideas. Another part of his quote states The Village of Skokie has shown only that the political views of Collin and his party are offensive and outrageous, which of course they are. They have failed to show any reason that the defendant planned to engage in any sort of illegal activity whatsoever. Lewison shows a very good understanding of the case he is involved in. He knows that Collins views are stupid and have no place in society. But Collin has made no threats to do anything illegal in his rally or march. All of the threats of violence have been made against him understandably. I strongly support Herb Lewison on thi s case. One of the best quotes in this whole legal battle came from the Judge who said, I believe he (Collin) intends to make trouble, to incite to riots and cause bodily harm. The Constitution certainly doesnt give a person like Collin the right to come into a peaceful community and cause violence. The Judge is looking at this from a point of view that most people would it is a very good analysis of what Collin intends to do. I understand the Judge on his standpoint but, like Lewison said he has not made any threat of illegal activity. I still say Collin has the right to speak under the First Amendment. I support the ACLU. No matter how brainless your statements might be you have the right to say it. If I wanted to say something and someone doesnt agree should I not be allowed to say it, truth or no truth to what Im saying.